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Find video protocols related to scientific articles indexed in Pubmed.
Autophagy modulates endoplasmic reticulum stress-induced cell death in podocytes: A protective role.
Exp. Biol. Med. (Maywood)
PUBLISHED: 10-18-2014
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Endoplasmic reticulum stress occurs in a variety of patho-physiological mechanisms and there has been great interest in managing this pathway for the treatment of clinical diseases. Autophagy is closely interconnected with endoplasmic reticulum stress to counteract the possible injurious effects related with the impairment of protein folding. Studies have shown that glomerular podocytes exhibit high rate of autophagy to maintain as terminally differentiated cells. In this study, podocytes were exposed to tunicamycin and thapsigargin to induce endoplasmic reticulum stress. Thapsigargin/tunicamycin treatment induced a significant increase in endoplasmic reticulum stress and of cell death, represented by higher GADD153 and GRP78 expression and propidium iodide flow cytometry, respectively. However, thapsigargin/tunicamycin stimulation also enhanced autophagy development, demonstrated by monodansylcadaverine assay and LC3 conversion. To evaluate the regulatory effects of autophagy on endoplasmic reticulum stress-induced cell death, rapamycin (Rap) or 3-methyladenine (3-MA) was added to enhance or inhibit autophagosome formation. Endoplasmic reticulum stress-induced cell death was decreased at 6?h, but was not reduced at 24?h after Rap+TG or Rap+TM treatment. In contrast, endoplasmic reticulum stress-induced cell death increased at 6 and 24?h after 3-MA+TG or 3-MA+TM treatment. Our study demonstrated that thapsigargin/tunicamycin treatment induced endoplasmic reticulum stress which resulted in podocytes death. Autophagy, which counteracted the induced endoplasmic reticulum stress, was simultaneously enhanced. The salvational role of autophagy was supported by adding Rap/3-MA to mechanistically regulate the expression of autophagy and autophagosome formation. In summary, autophagy helps the podocytes from cell death and may contribute to sustain the longevity as a highly differentiated cell lineage.
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Urinary neutrophil gelatinase-associated lipocalin and clinical outcomes in chronic kidney disease patients.
Clin. Chem. Lab. Med.
PUBLISHED: 08-07-2014
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Abstract Background: Tubulointerstitial damage is a final common pathway of most renal diseases. Whether urinary neutrophil gelatinase-associated lipocalin (uNGAL), a biomarker for renal tubular damage, is of prognostic value for clinical outcomes in chronic kidney disease (CKD) patients has not been well investigated. Methods: The uNGAL and proteinuria levels were measured among a cohort of 473 advanced CKD patients of various etiologies recruited during 2002-2009. Results: The estimated glomerular filtration rate (eGFR) was 32.3±22.0 mL/min/1.73 m2 with a urine protein-to-creatinine ratio (UPCR) 680 (255-1248) mg/g and 132 (27.9%) participants had diabetes. The baseline uNGAL level was significantly associated with male gender, eGFR, UPCR, and hemoglobin. The hazard ratio (HR) of the highest uNGAL tertile for end-stage renal disease (ESRD) was 3.44 (95% CI 1.47-8.06, p=0.004). With the adjustment of urine creatinine and urine protein, HR of the highest urine NGAL-to-creatinine ratio (UNCR) tertile and the highest urine NGAL-to-protein ratio (UNPR) tertile was 3.06 (95% CI 1.19-7.90, p=0.02) and 2.10 (95% CI 1.13-3.89, p=0.02), respectively. UNPR increased the prediction of survival model for ESRD. HR of the highest UNCR tertile and UNPR tertile for cardiovascular (CV) events was 2.21 (95% CI 0.81-5.98, p=0.08) and 2.79 (95% CI 1.25-6.26, p=0.01), respectively. None of these were associated with all-cause mortality. Conclusions: Elevated uNGAL in CKD patients is associated with risks for ESRD and probably CV events. UNPR could improve the prediction for ESRD.
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Multiple complexes of long aliphatic N-acyltransferases lead to synthesis of 2,6-diacylated/2-acyl-substituted glycopeptide antibiotics, effectively killing vancomycin-resistant enterococcus.
J. Am. Chem. Soc.
PUBLISHED: 07-25-2014
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Teicoplanin A2-2 (Tei)/A40926 is the last-line antibiotic to treat multidrug-resistant Gram-positive bacterial infections, e.g., methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE). This class of antibiotics is powered by the N-acyltransferase (NAT) Orf11*/Dbv8 through N-acylation on glucosamine at the central residue of Tei/A40926 pseudoaglycone. The NAT enzyme possesses enormous value in untapped applications; its advanced development is hampered largely due to a lack of structural information. In this report, we present eight high-resolution X-ray crystallographic unary, binary, and ternary complexes in order to decipher the molecular basis for NAT's functionality. The enzyme undergoes a multistage conformational change upon binding of acyl-CoA, thus allowing the uploading of Tei pseudoaglycone to enable the acyl-transfer reaction to take place in the occlusion between the N- and C-halves of the protein. The acyl moiety of acyl-CoA can be bulky or lengthy, allowing a large extent of diversity in new derivatives that can be formed upon its transfer. Vancomycin/synthetic acyl-N-acetyl cysteamine was not expected to be able to serve as a surrogate for an acyl acceptor/donor, respectively. Most strikingly, NAT can catalyze formation of 2-N,6-O-diacylated or C6?C2 acyl-substituted Tei analogues through an unusual 1,4-migration mechanism under stoichiometric/solvational reaction control, wherein selected representatives showed excellent biological activities, effectively counteracting major types (VanABC) of VRE.
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Variability in Estimated Glomerular Filtration Rate by Area under the Curve Predicts Renal Outcomes in Chronic Kidney Disease.
ScientificWorldJournal
PUBLISHED: 07-16-2014
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Greater variability in renal function is associated with mortality in patients with chronic kidney disease (CKD). However, few studies have demonstrated the predictive value of renal function variability in relation to renal outcomes. This study investigates the predictive ability of different methods of determining estimated glomerular filtration rate (eGFR) variability for progression to renal replacement therapy (RRT) in CKD patients. This was a prospective observational study, which enrolled 1,862 CKD patients. The renal end point was defined as commencement of RRT. The variability in eGFR was measured by the area under the eGFR curve (AUC)%. A significant improvement in model prediction was based on the -2 log likelihood ratio statistic. During a median 28.7-month follow-up, there were 564 (30.3%) patients receiving RRT. In an adjusted Cox model, a smaller initial eGFR AUC%_12M (P < 0.001), a smaller peak eGFR AUC%_12M (P < 0.001), and a larger negative eGFR slope_12M (P < 0.001) were associated with a higher risk of renal end point. Two calculated formulas: initial eGFR AUC%_12M and eGFR slope_12M were the best predictors. Our results demonstrate that the greater eGFR variability by AUC% is associated with the higher risk of progression to RRT.
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Multidisciplinary care improves clinical outcome and reduces medical costs for pre-end-stage renal disease in Taiwan.
Nephrology (Carlton)
PUBLISHED: 07-09-2014
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Multidisciplinary care (MDC) for patients with chronic kidney disease (CKD) may help to optimize disease care and improve clinical outcomes. Our study aimed to evaluate the effectiveness of pre-end-stage renal disease (ESRD) patients under MDC and usual care in Taiwan.
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Role of podocyte B7-1 in diabetic nephropathy.
J. Am. Soc. Nephrol.
PUBLISHED: 03-27-2014
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Podocyte injury and resulting albuminuria are hallmarks of diabetic nephropathy, but targeted therapies to halt or prevent these complications are currently not available. Here, we show that the immune-related molecule B7-1/CD80 is a critical mediator of podocyte injury in type 2 diabetic nephropathy. We report the induction of podocyte B7-1 in kidney biopsy specimens from patients with type 2 diabetes. Genetic and epidemiologic studies revealed the association of two single nucleotide polymorphisms at the B7-1 gene with diabetic nephropathy. Furthermore, increased levels of the soluble isoform of the B7-1 ligand CD28 correlated with the progression to ESRD in individuals with type 2 diabetes. In vitro, high glucose conditions prompted the phosphatidylinositol 3 kinase-dependent upregulation of B7-1 in podocytes, and the ectopic expression of B7-1 in podocytes increased apoptosis and induced disruption of the cytoskeleton that were reversed by the B7-1 inhibitor CTLA4-Ig. Podocyte expression of B7-1 was also induced in vivo in two murine models of diabetic nephropathy, and treatment with CTLA4-Ig prevented increased urinary albumin excretion and improved kidney pathology in these animals. Taken together, these results identify B7-1 inhibition as a potential therapeutic strategy for the prevention or treatment of diabetic nephropathy.
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Dysregulation of the TGFBI gene is involved in the oncogenic activity of the nonsense mutation of hepatitis B virus surface gene sW182*.
Biochim. Biophys. Acta
PUBLISHED: 03-05-2014
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The nonsense mutations of the hepatitis B virus (HBV) surface (S) gene have been reported to have oncogenic potential. We have previously identified several transforming nonsense mutations of the HBV S gene from hepatocarcinoma (HCC) patients. Among them, the sW182* mutant (the stop codon for tryptophan 182) showed the most potent oncogenicity in a mouse xenograft model using stably transfected mouse fibroblast cells. This study is aimed at understanding the molecular mechanisms leading to the oncogenic activity of the sW182* mutant. A gene expression microarray in combination with gene set enrichment analysis (GSEA) revealed differentially expressed gene sets in the sW182* cells, including those related to cell-cycle regulation, deoxyribonucleic acid repair, and genome instability. Of the differentially expressed genes, the transforming growth factor-?-induced (TGFBI) gene was further validated to be dysregulated in the sW182* cells. This dysregulation was accompanied by hypermethylation of the TGFBI promoter. The level of cyclin D1, a negatively regulated TGFBI target, was highly elevated in the sW182* mutant cells, which is consistent with the potent oncogenicity. Furthermore, frequent abnormal mitosis and multinucleation were observed in the mutant cells. Exogenous expression of TGFBI alleviated the oncogenic activity of the sW182* cells. In human HBV-related HCC cancerous tissue, expression of TGFBI was downregulated in 25 of the 55 (45%) patients examined, suggesting that TGFBI dysregulation could occur in HBV-related HCC development in some cases. These results suggest that dysregulation of TGFBI is involved in the oncogenic activity of the sW182* mutant of the hepatitis B virus S gene.
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Robust fuzzy control subject to state variance and passivity constraints for perturbed nonlinear systems with multiplicative noises.
ISA Trans
PUBLISHED: 02-14-2014
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The multi-constrained robust fuzzy control problem is investigated in this paper for perturbed continuous-time nonlinear stochastic systems. The nonlinear system considered in this paper is represented by a Takagi-Sugeno fuzzy model with perturbations and state multiplicative noises. The multiple performance constraints considered in this paper include stability, passivity and individual state variance constraints. The Lyapunov stability theory is employed to derive sufficient conditions to achieve the above performance constraints. By solving these sufficient conditions, the contribution of this paper is to develop a parallel distributed compensation based robust fuzzy control approach to satisfy multiple performance constraints for perturbed nonlinear systems with multiplicative noises. At last, a numerical example for the control of perturbed inverted pendulum system is provided to illustrate the applicability and effectiveness of the proposed multi-constrained robust fuzzy control method.
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Genetic polymorphisms of ORAI1 and chronic kidney disease in Taiwanese population.
Biomed Res Int
PUBLISHED: 02-06-2014
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Taiwan has very high incidence and prevalence of chronic kidney disease (CKD), which easily progresses to end-stage renal disease (ESRD). The association between inflammation and CKD has been explored in several studies. ORAI1 functions as a pore-forming subunit of the store-operated calcium channels which are involved in the regulation of immune system. Hence, we conducted a case-control study to determine whether the genetic polymorphisms of ORAI1 gene is a susceptibility factor to CKD and its clinical features in a Taiwanese population. Five hundred seventy-nine CKD patients from a hospital-based CKD care program were included in the study. Five tagging single nucleotide polymorphisms (tSNPs) of ORAI1 were selected from the genotyping data of the Han Chinese population from the HapMap project. Among these polymorphisms, rs12313273 was found to be significantly associated with elevated serum calcium levels, which has been linked to increased risk of death in CKD patients. To have a better management of serum calcium, we suggest that ORAI1 polymorphisms might be used as a potential biomarker for initiating non-calcium-based phosphate binder in CKD patients in the future.
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Relationship of perceived environmental barriers and disability in community-dwelling elderly in Taiwan--a population-based study.
BMC Geriatr
PUBLISHED: 01-25-2014
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To identify the relationship between perceived environmental barriers and disability in community-dwelling elderly.
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Insights into the binding specificity and catalytic mechanism of N-acetylhexosamine 1-phosphate kinases through multiple reaction complexes.
Acta Crystallogr. D Biol. Crystallogr.
PUBLISHED: 01-24-2014
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Utilization of N-acetylhexosamine in bifidobacteria requires the specific lacto-N-biose/galacto-N-biose pathway, a pathway differing from the Leloir pathway while establishing symbiosis between humans and bifidobacteria. The gene lnpB in the pathway encodes a novel hexosamine kinase NahK, which catalyzes the formation of N-acetylhexosamine 1-phosphate (GlcNAc-1P/GalNAc-1P). In this report, seven three-dimensional structures of NahK in complex with GlcNAc, GalNAc, GlcNAc-1P, GlcNAc/AMPPNP and GlcNAc-1P/ADP from both Bifidobacterium longum (JCM1217) and B. infantis (ATCC15697) were solved at resolutions of 1.5-2.2 Å. NahK is a monomer in solution, and its polypeptide folds in a crescent-like architecture subdivided into two domains by a deep cleft. The NahK structures presented here represent the first multiple reaction complexes of the enzyme. This structural information reveals the molecular basis for the recognition of the given substrates and products, GlcNAc/GalNAc, GlcNAc-1P/GalNAc-1P, ATP/ADP and Mg(2+), and provides insights into the catalytic mechanism, enabling NahK and mutants thereof to form a choice of biocatalysts for enzymatic and chemoenzymatic synthesis of carbohydrates.
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Risks of musculoskeletal disorders among betel quid preparers in Taiwan.
Am. J. Ind. Med.
PUBLISHED: 01-24-2014
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Betel quid chewing is common in Taiwan. The work of betel quid preparers is characterized by long hours of static work, awkward working posture and highly repetitive hand/wrist motion. However, the musculoskeletal health of betel quid preparers receives very little attention.
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Biosynthesis of streptolidine involved two unexpected intermediates produced by a dihydroxylase and a cyclase through unusual mechanisms.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 01-21-2014
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Streptothricin-F (STT-F), one of the early-discovered antibiotics, consists of three components, a ?-lysine homopolymer, an aminosugar D-gulosamine, and an unusual bicyclic streptolidine. The biosynthesis of streptolidine is a long-lasting but unresolved puzzle. Herein, a combination of genetic/biochemical/structural approaches was used to unravel this problem. The STT gene cluster was first sequenced from a Streptomyces variant BCRC 12163, wherein two gene products OrfP and OrfR were characterized in?vitro to be a dihydroxylase and a cyclase, respectively. Thirteen high-resolution crystal structures for both enzymes in different reaction intermediate states were snapshotted to help elucidate their catalytic mechanisms. OrfP catalyzes an Fe(II) -dependent double hydroxylation reaction converting L-Arg into (3R,4R)-(OH)2 -L-Arg via (3S)-OH-L-Arg, while OrfR catalyzes an unusual PLP-dependent elimination/addition reaction cyclizing (3R,4R)-(OH)2 -L-Arg to the six-membered (4R)-OH-capreomycidine. The biosynthetic mystery finally comes to light as the latter product was incorporation into STT-F by a feeding experiment.
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The mechanisms by which pardaxin, a natural cationic antimicrobial peptide, targets the endoplasmic reticulum and induces c-FOS.
Biomaterials
PUBLISHED: 01-08-2014
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Pardaxin is a cationic antimicrobial peptide derived from Red Sea Moses sole. Previous studies have shown that pardaxin selectively triggers the death of cancer cells, initiating the development of a pardaxin-based cancer vaccine; however, the underlying mechanism by which pardaxin kills cancer cells has not yet been elucidated. Here, we demonstrate that this mechanism involves endoplasmic reticulum (ER) targeting and c-FOS induction. Transcriptiome analysis of pardaxin-treated HT-1080 cells revealed induction of the gene encoding c-FOS, an AP-1 transcription factor. Pardaxin mediates cell death by activating c-FOS, but not other AP-1 transcription factors. Overexpression of c-FOS caused a dramatic increase in cell death, while knockdown of c-FOS induced pardaxin resistance; such effects were observed in both an in vitro cell model and an in vivo xenograft tumor model. Treatment with pardaxin also increased the level of calcium, and blockage of cellular calcium signaling disrupted pardaxin-induced cell death. Immunocytochemistry was used to demonstrate targeting of pardaxin to the endoplasmic reticulum, but not to the Golgi apparatus or mitochondria. Importantly, pardaxin treatment or c-FOS overexpression induced cell death in diverse cancer cell lines, indicating that pardaxin and c-FOS may possess therapeutic potential for use in cancer treatment.
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Structure and mechanism of a nonhaem-iron SAM-dependent C-methyltransferase and its engineering to a hydratase and an O-methyltransferase.
Acta Crystallogr. D Biol. Crystallogr.
PUBLISHED: 01-06-2014
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In biological systems, methylation is most commonly performed by methyltransferases (MTs) using the electrophilic methyl source S-adenosyl-L-methionine (SAM) via the S(N)2 mechanism. (2S,3S)-?-Methylphenylalanine, a nonproteinogenic amino acid, is a building unit of the glycopeptide antibiotic mannopeptimycin. The gene product of mppJ from the mannopeptimycin-biosynthetic gene cluster is the MT that methylates the benzylic C atom of phenylpyruvate (Ppy) to give ?MePpy. Although the benzylic C atom of Ppy is acidic, how its nucleophilicity is further enhanced to become an acceptor for C-methylation has not conclusively been determined. Here, a structural approach is used to address the mechanism of MppJ and to engineer it for new functions. The purified MppJ displays a turquoise colour, implying the presence of a metal ion. The crystal structures reveal MppJ to be the first ferric ion SAM-dependent MT. An additional four structures of binary and ternary complexes illustrate the molecular mechanism for the metal ion-dependent methyltransfer reaction. Overall, MppJ has a nonhaem iron centre that bind, orients and activates the ?-ketoacid substrate and has developed a sandwiched bi-water device to avoid the formation of the unwanted reactive oxo-iron(IV) species during the C-methylation reaction. This discovery further prompted the conversion of the MT into a structurally/functionally unrelated new enzyme. Through stepwise mutagenesis and manipulation of coordination chemistry, MppJ was engineered to perform both Lewis acid-assisted hydration and/or O-methyltransfer reactions to give stereospecific new compounds. This process was validated by six crystal structures. The results reported in this study will facilitate the development and design of new biocatalysts for difficult-to-synthesize biochemicals.
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A Stabilization Device That Promotes the Efficiency of Cardiopulmonary Resuscitation during Ambulance Transportation to the Level as under Non-Moving Conditions.
PLoS ONE
PUBLISHED: 01-01-2014
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The survival rate of patients with out-of-hospital cardiac arrest is low, and measures to improve the quality of cardiopulmonary resuscitation (CPR) during ambulance transportation are desirable. We designed a stabilization device, and in a randomized crossover trial we found performing CPR in a moving ambulance with the device (MD) could achieve better efficiency than that without the device (MND), but the efficiency was lower than that in a non-moving ambulance (NM).
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P wave dispersion and maximum P wave duration are associated with renal outcomes in chronic kidney disease.
PLoS ONE
PUBLISHED: 01-01-2014
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P wave parameters measured by 12-lead electrocardiogram (ECG) are commonly used as a noninvasive tool to evaluate left atrial enlargement. This study was designed to assess whether P wave parameters were associated with renal outcomes in chronic kidney disease (CKD) patients. This longitudinal study enrolled 439 patients with CKD stages 3-5. Renal end points were defined as the commencement of dialysis or death. Change in renal function was measured using the estimated glomerular filtration rate (eGFR) slope. We measured two ECG P wave parameters corrected for heart rate, i.e., corrected P wave dispersion and corrected maximum P wave duration. The values of P wave dispersion and maximum P wave duration were 88.8±21.7 ms and 153.3±21.7 ms, respectively. During the follow-up period (mean, 25.2 months), 95 patients (21.6%) started hemodialysis and 30 deaths (6.8%) were recorded. Multivariate Cox regression analysis identified that increased P wave dispersion [hazard ratio (HR), 1.020; 95% confidence interval (CI), 1.009-1.032; P<0.001] and maximum P wave duration (HR, 1.013; 95% CI, 1.003-1.024; P?=?0.012) were associated with progression to renal end points. Furthermore, increased P wave dispersion (unstandardized coefficient ??=?-0.016; P?=?0.037) and maximum P wave duration (unstandardized coefficient ??=?-0.014; P?=?0.040) were negatively associated with the eGFR slope. We demonstrated that increased P wave dispersion and maximum P wave duration were associated with progression to the renal end points of dialysis or death and faster renal function decline in CKD patients. Screening CKD patients on the basis of P wave dispersion and maximum P wave duration may help identify patients at high risk for worse renal outcomes.
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Hepatitis C virus infection increases risk of developing end-stage renal disease using competing risk analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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Chronic kidney disease (CKD) and hepatitis C virus (HCV) infection are closely linked and both increase patient mortality. The association of HCV and risk of developing end-stage renal disease (ESRD) has not been analyzed with competing risk model.
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Improving anticancer efficacy of (-)-epigallocatechin-3-gallate gold nanoparticles in murine B16F10 melanoma cells.
Drug Des Devel Ther
PUBLISHED: 01-01-2014
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(-)-Epigallocatechin-3-gallate (EGCG), the major bioactive constituent in green tea, has been reported to effectively inhibit the formation and development of tumors. To maximize the effectiveness of EGCG, we attached it to nanogold particles (EGCG-pNG) in various ratios to examine in vitro cytotoxicity and in vivo anti-cancer activity. EGCG-pNG showed improved anti-cancer efficacy in B16F10 murine melanoma cells; the cytotoxic effect in the melanoma cells treated with EGCG-pNG was 4.91 times higher than those treated with EGCG. The enhancement is achieved through mitochondrial pathway-mediated apoptosis as determined by annexin V assay, JC-10 staining, and caspase-3, -8, -9 activity assay. Moreover, EGCG-pNG was 1.66 times more potent than EGCG for inhibition of tumor growth in a murine melanoma model. In the hemolysis assay, the pNG surface conjugated with EGCG is most likely the key factor that contributes to the decreased release of hemoglobin from human red blood cells.
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Association of relatives of hemodialysis patients with metabolic syndrome, albuminuria and Framingham Risk Score.
PLoS ONE
PUBLISHED: 01-01-2014
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Metabolic syndrome (MetS), albuminuria, and the Framingham Risk Score (FRS) are significant predictors for cardiovascular disease (CVD). However, the relationship and clinical significance of these CVD predictors in individuals with a family history of end-stage renal disease (ESRD) are unclear. We investigated the association of relatives of hemodialysis (HD) patients with MetS, albuminuria, and the FRS.
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Discrepancy between serological and virological analysis of viral hepatitis in hemodialysis patients.
Int J Med Sci
PUBLISHED: 01-01-2014
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Viral hepatitis is a health threat for hemodialysis (HD) patients and it may be transmitted during treatment. Some patients categorized to have viral hepatitis were found to be non-viremic. To clarify the discrepancy between the serological tests in HD patients, we conducted the study.
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Use of the antimicrobial peptide pardaxin (GE33) to protect against MRSA infection in mice with skin injuries.
Antimicrob. Agents Chemother.
PUBLISHED: 12-23-2013
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Antimicrobial peptides (AMPs) have recently been determined to be potential candidates for treating drug-resistant bacterial infections. GE33, a marine antimicrobial peptide also known as pardaxin, has been reported to possess antimicrobial function. In this study, we investigated whether GE33 promoted healing of contaminated wounds in mice. One square centimeter of outer skin was excised from the ventral region of mice, and a lethal dose of MRSA was applied in the presence or absence of methicillin, vancomycin, or GE33. While untreated mice and mice treated with methicillin died within three days, mice treated with GE33 survived infection. GE33 decreased MRSA bacterial counts in the wounded region, and also enhanced wound closure. Re-epithelialization and dermal maturation were also faster in mice treated with GE33, as compared to mice treated with vancomycin. In addition, GE33 treatment controlled excess recruitment of monocytes and macrophage cells, and increased the expression of VEGF. In conclusion, these results suggest that GE33 is capable of enhancing wound healing. Furthermore, this study provides an excellent platform for comparing the antimicrobial activities of peptide and non-peptide antibiotics.
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miRNA-491-5p and GIT1 serve as modulators and biomarkers for oral squamous cell carcinoma (OSCC) invasion and metastasis.
Cancer Res.
PUBLISHED: 12-12-2013
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microRNAs offer tools to identify and treat invasive cancers. Using highly invasive isogenic oral squamous cell carcinoma (OSCC) cells established using in vitro and in vivo selection protocols from poorly invasive parental cell populations, we used microarray expression analysis to identify a relative and specific decrease in miR-491-5p in invasive cells. Lower expression of miR-491-5p correlated with poor overall survival of OSCC patients. miR-491-5p overexpression in invasive OSCC cells suppressed their migratory behavior in vitro and lung metastatic behavior in vivo. We defined the G protein-coupled receptor kinase-interacting protein 1 (GIT1) as a direct target gene for miR-491-5p control. GIT1 overexpression was sufficient to rescue miR-491-5p-mediated inhibition of migration/invasion and lung metastasis. Conversely, GIT1 silencing phenocopied the ability of miR-491-5p to inhibit migration/invasion and metastasis of OSCC cells. Mechanistic investigations indicated that miR-491-5p overexpression or GIT1 attenuation reduced focal adhesions, with a concurrent decrease in steady-state levels of paxillin, phospho-paxillin, phospho-FAK, EGF/EGFR-mediated ERK1/2 activation and MMP2/9 levels and activities. In clinical specimens of OSCC, GIT1 levels were elevated relative to paired normal tissues and were correlated with lymph node metastasis, with expression levels of miR-491-5p and GIT1 correlated inversely in OSCC where they informed tumor grade. Together, our findings identify a functional axis for OSCC invasion that suggests miR-491-5p and GIT1 as biomarkers for prognosis in this cancer.
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Abatacept in B7-1-positive proteinuric kidney disease.
N. Engl. J. Med.
PUBLISHED: 11-08-2013
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Abatacept (cytotoxic T-lymphocyte-associated antigen 4-immunoglobulin fusion protein [CTLA-4-Ig]) is a costimulatory inhibitor that targets B7-1 (CD80). The present report describes five patients who had focal segmental glomerulosclerosis (FSGS) (four with recurrent FSGS after transplantation and one with primary FSGS) and proteinuria with B7-1 immunostaining of podocytes in kidney-biopsy specimens. Abatacept induced partial or complete remissions of proteinuria in these patients, suggesting that B7-1 may be a useful biomarker for the treatment of some glomerulopathies. Our data indicate that abatacept may stabilize ?1-integrin activation in podocytes and reduce proteinuria in patients with B7-1-positive glomerular disease.
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Inhibition of type I interferon signalling prevents TLR ligand-mediated proteinuria.
J. Pathol.
PUBLISHED: 10-24-2013
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The mechanisms by which inflammation or autoimmunity causes proteinuric kidney disease remain elusive. Yet proteinuria is a hallmark and a prognostic indicator of kidney disease, and also an independent risk factor for cardiovascular morbidity and mortality. Podocytes are an integral component of the kidney filtration barrier and podocyte injury leads to proteinuria. Here we show that podocytes, which receive signals from the vascular space including circulating antigens, constitutively express TLR1–6 and TLR8. We find that podocytes can respond to TLR ligands including staphylococcal enterotoxin B (SEB), poly I:C, or lipopolysaccharide (LPS) with pro-inflammatory cytokine release and activation of type I interferon (IFN) signalling. This in turn stimulates podocyte B7-1 expression and actin remodelling in vitro and transient proteinuria in vivo. Importantly, the treatment of mice with a type I IFN receptor-blocking antibody (Ab) prevents LPS-induced proteinuria. These results significantly extend our understanding of podocyte response to immune stimuli and reveal a novel mechanism for infection- or inflammation-induced transient proteinuria. Dysregulation or aberrant activation of this response may result in persistent proteinuria and progressive glomerular disease. In summary, the inhibition of glomerular type I IFN signalling with anti-IFN Abs may be a novel therapy for proteinuric kidney diseases.
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An open-label, randomized, controlled trial of zotepine and risperidone for acutely ill, hospitalized, schizophrenic patients with symptoms of agitation.
J Clin Psychopharmacol
PUBLISHED: 10-09-2013
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Acutely ill, schizophrenic patients frequently require management of agitation. This study was conducted to compare the efficacy of oral zotepine and risperidone in hospitalized, acutely ill schizophrenic patients with symptoms of agitation.This was a 6-week, multicenter, randomized, open-label, parallel-group, flexible dosing study. Thirty-nine patients with schizophrenia (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) who met the criteria of a Positive and Negative Syndrome Scale (PANSS) total score of greater than or equal to 60 points, PANSS-excitement component (EC) score of greater than or equal to 14 points, and at least 1 PANSS-EC score of greater than or equal to 4 were randomly assigned to either the zotepine or risperidone group. The primary outcome was a comparison of the change in the PANSS-EC total score from baseline to the end of the study between groups.There was no significant between-group difference in dropout rates (zotepine, 15.8% [3/19]; risperidone, 20.0% [4/20]). The mean (SD) daily dose of zotepine from baseline to study end point ranged from 127.6 (62.3) to 236.8 (74.2) mg/d; the corresponding values for risperidone ranged from 3.3 (1.6) to 4.8 (1.7) mg/d. There were no statistically significant differences in patient characteristics, PANSS total score, and PANSS-EC total score between the zotepine and risperidone groups at baseline. Both groups showed significant reductions in the PANSS-EC total scores (zotepine, -10.1 [4.7], P < 0.001; risperidone, -8.0 [5.3], P < 0.001) and PANSS total scores (zotepine, -34.7 [15.8], P < 0.001; risperidone, -28.6 [14.3], P < 0.001). However, there were no significant differences in PANSS-EC total score (P = 0.265) and PANSS total score (P = 0.125) changes from baseline to study end point between the 2 treatment groups. Serum uric acid and prolactin decreased more in the zotepine group than the risperidone group (P < 0.001 and P = 0.018, respectively).Zotepine seemed to be as effective as risperidone in treating hospitalized, acutely ill, schizophrenic patients with agitation, and had the advantages of lowering hyperuricemia and hyperprolactinemia. Double-blind, fixed dose studies with a larger sample size of acutely ill, schizophrenic patients with agitation are needed to confirm the study results.
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Motor neuron expression of the voltage-gated calcium channel cacophony restores locomotion defects in a Drosophila, TDP-43 loss of function model of ALS.
Brain Res.
PUBLISHED: 08-25-2013
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Dysfunction of the RNA-binding protein, TDP-43, is strongly implicated as a causative event in many neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). TDP-43 is normally found in the nucleus and pathological hallmarks of ALS include the presence of cytoplasmic protein aggregates containing TDP-43 and an associated loss of TDP-43 from the nucleus. Loss of nuclear TDP-43 likely contributes to neurodegeneration. Using Drosophila melanogaster to model TDP-43 loss of function, we show that reduced levels of the voltage-gated calcium channel, cacophony, mediate some of the physiological effects of TDP-43 loss. Null mutations in the Drosophila orthologue of TDP-43, named TBPH, resulted in defective larval locomotion and reduced levels of cacophony protein in whole animals and at the neuromuscular junction. Restoring the levels of cacophony in all neurons or selectively in motor neurons rescued these locomotion defects. Using TBPH immunoprecipitation, we showed that TBPH associates with cacophony transcript, indicating that it is likely to be a direct target for TBPH. Loss of TBPH leads to reduced levels of cacophony transcript, possibly due to increased degradation. In addition, TBPH also appears to regulate the inclusion of some alternatively spliced exons of cacophony. If similar effects of cacophony or related calcium channels are found in human ALS patients, these could be targets for the development of pharmacological therapies for ALS. This article is part of a Special Issue entitled RNA Metabolism 2013.
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Use of the antimicrobial peptide Epinecidin-1 to protect against MRSA infection in mice with skin injuries.
Biomaterials
PUBLISHED: 08-15-2013
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Methicillin-resistant Staphylococcus aureus (MRSA) causes infections through open skin injuries, and its resistance makes treatment difficult. The antimicrobial peptide Epinecidin-1 (Epi-1) has been reported to possess antibacterial, antifungal, antiviral, and antitumor functions. This study investigated the antimicrobial activity of Epi-1 against skin trauma-mediated MRSA infection in mice. One square centimeter of outer skin was excised from the ventral region of mice, and a lethal dose of MRSA was applied in the presence or absence of methicillin, vancomycin, or Epi-1. While untreated mice and mice treated with methicillin died within four days, mice treated with Epi-1 survived infection. Epi-1 decreased MRSA bacterial counts in the wounded region, enhanced wound closure, and increased angiogenesis at the injury site. Treatment with Epi-1 decreased serum levels of the proinflammatory cytokines TNF-?, IL-6, and MCP-1, and regulated the recruitment of monocytes and clearance of lymphocytes around the wounded region during healing. In conclusion, Epi-1 may be effective at treating clinical MRSA, and may enhance wound recovery when combined with collagen.
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Dyslipoproteinemia and impairment of renal function in diabetic kidney disease: an analysis of animal studies, observational studies, and clinical trials.
Rev Diabet Stud
PUBLISHED: 08-10-2013
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Dyslipoproteinemia is highly prevalent in diabetes, chronic kidney disease, and diabetic kidney disease (DKD). Both diabetes and chronic kidney disease (CKD) are associated with hypertriglyceridemia, lower high-density lipoprotein, and higher small, dense low-density lipoprotein. A number of observational studies have reported that dyslipidemia may be associated with albuminuria, renal function impairment, and end-stage renal disease (ESRD) in the general population, and especially in CKD and DKD patients. Diabetic glomerulopathy and the related albuminuria are the main manifestations of DKD. Numerous animal studies support the finding that glomerular atherosclerosis is the main mechanism of glomerulosclerosis in CKD and DKD. Some randomized, controlled trials suggest the use of statins for the prevention of albuminuria and renal function impairment in CKD and DKD patients. However, a large clinical study, the Study of Heart and Renal Protection (SHARP), does not support that statins could reduce ESRD in CKD. In this article, we analyze the complex association of dyslipoproteinemia with DKD and deduce its relevance from animal studies, observational studies, and clinical trials. We show that special subgroups could benefit from the statin treatment.
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Association of cholesterol levels with mortality and cardiovascular events among patients with CKD and different amounts of proteinuria.
Clin J Am Soc Nephrol
PUBLISHED: 08-08-2013
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Malnutrition and/or inflammation may modify the risk relationship of total cholesterol with cardiovascular disease in CKD patients. However, it is unclear whether the relationship of total cholesterol with cardiovascular events and mortality varies by proteinuria.
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Save life and improve quality: Report from the 5th Congress of International Society for Hemodialysis.
Hemodial Int
PUBLISHED: 07-30-2013
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The 5th congress of International Society for Hemodialysis took place last August 3-5, 2012 at the Grand Hotel in Taipei and focused on "Save Life and Improve Quality." It attracted a total of 927 participants from 18 countries. The full spectrum of hemodialysis was covered with plenary lectures and symposiums delivered by experts from different subspecialties in nephrology starting from the history of hemodialysis, mineral bone disease, microinflammation and advanced techniques in hemodialysis. It was followed by critical care in nephrology, anemia, and nutrition in dialysis. Last but not the least, natural disasters and medical economics in hemodialysis were also discussed extensively. This special article will highlight the authentic contributions and innovative clinical presentations from the meeting.
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Association of metabolic syndrome and albuminuria with cardiovascular risk in occupational drivers.
Int J Mol Sci
PUBLISHED: 07-29-2013
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Metabolic syndrome (MetS) and albuminuria increase cardiovascular risk. However, in occupational drivers, the clinical significance of albuminuria and its association with MetS remain unclear. We investigated the prevalence of MetS, albuminuria and cardiovascular risk, and its associated risk factors in occupational drivers;
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A cancer vaccine based on the marine antimicrobial peptide pardaxin (GE33) for control of bladder-associated tumors.
Biomaterials
PUBLISHED: 07-11-2013
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The marine antimicrobial peptide (AMP) GE33, also known as pardaxin, possesses antimicrobial and anticancer properties, and modulates host signaling. GE33 has cytotoxic effects on murine bladder carcinoma (MBT-2) cells. Here, we investigated the potential of GE33 combined with inactivated MBT-2 as a cancer vaccine. The presence of up to 12.5 ?g of GE33 did not inhibit the proliferation or endogenous nitrous oxide (NO) levels of RAW264.7 cells. However, the secretion of MCP-1, IL-6, and IL-12 by RAW264.7 cells was affected by GE33. We proceeded to test the effectiveness of the vaccine by immunizing mice at 7, 14, and 21 days of age, and injecting live MBT-2 cells on the 28th day. Tumor growth by the 58th day was attenuated in mice treated with the vaccine, as compared to the control group. Induction of MBT-2 specific-tumor antigens was increased in mice immunized with our vaccine. Furthermore, activation of T-cell receptors, cytotoxic T-cells, and NK cells was enhanced, and these showed high specificity for targeting tumor cells. Finally, immunization controlled excess recruitment of monocytes, lymphocytes, T-helper cells, and NK cells, and decreased the expression of VEGF. This report provides empirical evidence that our GE33-based vaccine enhances antitumor immunity in mice.
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High hepatitis B virus surface antigen levels and favorable interleukin 28B genotype predict spontaneous hepatitis C virus clearance in uremic patients.
J. Hepatol.
PUBLISHED: 07-04-2013
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Host and viral factors interplay in the spontaneous clearance of hepatitis C virus (HCV) infection. We aimed to explore the roles of IL28B genotypes and hepatitis B virus (HBV) infections in spontaneous HCV seroclearance.
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Performance of the Framingham risk score in patients receiving hemodialysis.
Nephrology (Carlton)
PUBLISHED: 04-28-2013
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The Framingham Risk Score (FRS), calculated by considering conventional risk factors of cardiovascular diseases, was developed to predict coronary heart disease in various populations. However, reverse epidemiology has been raised concerning these risk factors in predicting high cardiovascular mortality in hemodialysis patients. Our objectives are to determine whether FRS is associated with overall and cardiovascular mortality and the role of new risk markers when they were added to a FRS model in hemodialysis patients.
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Ratio of transmitral E-wave velocity to early diastole mitral annulus velocity with cardiovascular and renal outcomes in chronic kidney disease.
Nephron Clin Pract
PUBLISHED: 04-16-2013
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Impaired left ventricular diastolic function and increased left ventricular filling pressure are frequently noted in patients with chronic kidney disease (CKD), even in early stages. The association of increased left ventricular filling pressure with cardiovascular and renal outcomes remains uncertain in CKD. This study is designed to assess whether the ratio of transmitral E-wave velocity (E) to early diastole mitral velocity (Ea) is associated with cardiovascular events and progression to dialysis in patients with CKD stages 3-5.
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Atypical X-linked agammaglobulinaemia caused by a novel BTK mutation in a selective immunoglobulin M deficiency patient.
BMC Pediatr
PUBLISHED: 03-18-2013
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X-linked agammaglobulinaemia (XLA) is the most common inherited humoural immunodeficiency disorder. Mutations in the gene coding for Brutons tyrosine kinase (BTK) have been identified as the cause of XLA. Most affected patients exhibit a marked reduction of serum immunoglobulins, mature B cells, and an increased susceptibility to recurrent bacterial infections. However, the diagnosis of XLA can be a challenge in certain patients who have near-normal levels of serum immunoglobulin. Furthermore, reports on XLA with renal involvement are scant.
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Lethal cardiac arrhythmia during central venous catheterization in a uremic patient: a case report and review of the literature.
Hemodial Int
PUBLISHED: 03-06-2013
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Double-lumen central venous catheter (CVC) is a rapid access technique for hemodialysis (HD) when an arteriovenous fistula or graft is not available. A variety of procedure-related complications have been reported, such as infection and pneumothorax, but serious cardiac complications are relatively less mentioned. We report a uremic woman with preexisting left bundle branch block who required emergent HD and received jugular double-lumen CVC insertion, which was complicated by short-duration ventricular tachycardia followed by complete atrio-ventricular block and bradycardia. Pharmacological management did not reverse heart rate and rhythm. External pacing was not applied because she remained hemodynamically stable in the course of HD. Heart rate returned to sinus rhythm with left bundle branch block 4 hours later and did not recur through the whole admission period. We speculate that the transient arrhythmia might have been induced by mechanical contact with the ventricular wall during the procedure with the guided metallic wire. In conclusion, physicians responsible for CVC catheterization should pay more attention to patients with preexisting cardiac arrhythmia to prevent such technical mistakes from transpiring.
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A stabilization device to improve the quality of cardiopulmonary resuscitation during ambulance transportation: a randomized crossover trial.
Resuscitation
PUBLISHED: 02-22-2013
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The quality of cardiopulmonary resuscitation (CPR) during ambulance transportation is suboptimal, and therefore measures that can improve the quality are desirable.
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Framingham risk score with cardiovascular events in chronic kidney disease.
PLoS ONE
PUBLISHED: 02-19-2013
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The Framingham Risk Score (FRS) was developed to predict coronary heart disease in various populations, and it tended to under-estimate the risk in chronic kidney disease (CKD) patients. Our objectives were to determine whether FRS was associated with cardiovascular events, and to evaluate the role of new risk markers and echocardiographic parameters when they were added to a FRS model. This study enrolled 439 CKD patients. The FRS is used to identify individuals categorically as "low" (<10% of 10-year risk), "intermediate" (10-20% risk) or "high" risk (? 20% risk). A significant improvement in model prediction was based on the -2 log likelihood ratio statistic and c-statistic. "High" risk (v.s. "low" risk) predicts cardiovascular events either without (hazard ratios [HR] 2.090, 95% confidence interval [CI] 1.144 to 3.818) or with adjustment for clinical, biochemical and echocardiographic parameters (HR 1.924, 95% CI 1.008 to 3.673). Besides, the addition of albumin, hemoglobin, estimated glomerular filtration rate, proteinuria, left atrial diameter >4.7 cm, left ventricular hypertrophy or left ventricular ejection fraction<50% to the FRS model significantly improves the predictive values for cardiovascular events. In CKD patients, "high" risk categorized by FRS predicts cardiovascular events. Novel biomarkers and echocardiographic parameters provide additional predictive values for cardiovascular events. Future study is needed to assess whether risk assessment enhanced by using these biomarkers and echocardiographic parameters might contribute to more effective prediction and better care for patients.
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Association of dyslipidemia with renal outcomes in chronic kidney disease.
PLoS ONE
PUBLISHED: 02-04-2013
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Dyslipidemia is highly prevalent in patients with chronic kidney disease (CKD) and the relationship between dyslipidemia with renal outcomes in patients with moderate to advanced CKD remains controversial. Hence, our objective is to determine whether dyslipidemia is independently associated with rapid renal progression and progression to renal replacement therapy (RRT) in CKD patients. The study analyzed the association between lipid profile, RRT, and rapid renal progression (estimated glomerular filtration rate [eGFR] slope <-6 ml/min/1.73 m(2)/yr) in 3303 patients with stages 3 to 5 CKD. During a median 2.8-year follow-up, 1080 (32.3%) participants commenced RRT and 841 (25.5%) had rapid renal progression. In the adjusted models, the lowest quintile (hazard ratios [HR], 1.23; 95% confidence interval [CI], 1.01 to 1.49) and the highest two quintiles of total cholesterol (HR, 1.25; 95% CI, 1.02 to 1.52 and HR, 1.35; 95% CI, 1.11 to 1.65 respectively) increased risks for RRT (vs. quintile 2). Besides, the highest quintile of total cholesterol was independently associated with rapid renal progression (odds ratio, 1.36; 95% CI, 1.01 to 1.83). Our study demonstrated that certain levels of dyslipidemia were independently associated with RRT and rapid renal progression in CKD stage 3-5. Assessment of lipid profile may help identify high risk groups with adverse renal outcomes.
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Reduction of splenic immunosuppressive cells and enhancement of anti-tumor immunity by synergy of fish oil and selenium yeast.
PLoS ONE
PUBLISHED: 01-22-2013
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Growing evidence has shown that regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) abnormally increase in cancer cachectic patients. Suppressions of Tregs and MDSCs may enhance anti-tumor immunity for cancer patients. Fish oil and selenium have been known to have many biological activities such as anti-inflammation and anti-oxidation. Whether fish oil and/or selenium have an additional effect on population of immunosuppressive cells in tumor-bearing hosts remained elusive and controversial. To gain insights into their roles on anti-tumor immunity, we studied the fish oil- and/or selenium-mediated tumor suppression and immunity on lung carcinoma, whereof cachexia develops. Advancement of cachexia in a murine lung cancer model manifested with such indicative symptoms as weight loss, chronic inflammation and disturbed immune functionality. The elevation of Tregs and MDSCs in spleens of tumor-bearing mice was positively correlated with tumor burdens. Consumption of either fish oil or selenium had little or no effect on the levels of Tregs and MDSCs. However, consumption of both fish oil and selenium together presented a synergistic effect--the population of Tregs and MDSCs decreased as opposed to increase of anti-tumor immunity when both fish oil and selenium were supplemented simultaneously, whereby losses of body weight and muscle/fat mass were alleviated significantly.
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Left atrial diameter and albumin with renal outcomes in chronic kidney disease.
Int J Med Sci
PUBLISHED: 01-09-2013
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Echocardiographic left atrial diameter (LAD) has been documented to be an independent predictor of adverse cardiovascular outcomes in various populations. An enlarged left atrium is frequently noted in chronic kidney disease (CKD). We examined the association between albumin and indexed LAD (indexed to height) and assessed whether the combination of indexed LAD and albumin was independently associated with renal outcomes in patients with CKD stages 3-5.
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Omega-3 fatty acid-, micronutrient-, and probiotic-enriched nutrition helps body weight stabilization in head and neck cancer cachexia.
Oral Surg Oral Med Oral Pathol Oral Radiol
PUBLISHED: 01-07-2013
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To evaluate whether an oral nutritional supplement enriched with omega-3 fatty acids, micronutrients, and probiotics affected body weight (BW) changes, serum albumin and prealbumin levels in patients with head and neck cancer (HNC) cachexia.
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Hypokalemia, its contributing factors and renal outcomes in patients with chronic kidney disease.
PLoS ONE
PUBLISHED: 01-01-2013
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In the chronic kidney disease (CKD) population, the impact of serum potassium (sK) on renal outcomes has been controversial. Moreover, the reasons for the potential prognostic value of hypokalemia have not been elucidated.
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The relationship between health-promoting behaviors and resilience in patients with chronic kidney disease.
ScientificWorldJournal
PUBLISHED: 01-01-2013
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This cross-sectional research study explored differences in health-promoting behavior and resilience among three groups of chronic kidney disease patients (high-risk, early chronic kidney disease; early CKD and pre-end stage renal disease; pre-ESRD) treated at the Nephrology outpatient clinic in northern Taiwan. A total of 150 CKD outpatients were interviewed using structured questionnaires including a CKD Health to Promote Lifestyle Scale, and resilience scale. We found that the pre-ESRD group had lower resilience than either high-risk or early CKD groups. Factors affecting pre-ESRD resilience were gender, occupational status, diabetes and health-promoting behaviors. Factors affecting resilience of the high-risk group included level of education and health-promoting behaviors while factors affecting resilience in the early CKD group involved whether they are employed and health promoting behaviors. A significant positive correlation was found between health promoting behavior and resilience in all study subjects. Multiple regression analysis found that factors which could effectively predict resilience in patients at high-risk for CKD were gender, whether the patient had a job, nutrition, self-actualization, and stress level, accounting for 69.7% of the variance. Therefore, nursing education should focus on health promotion advocacy throughout the life of not only patients but also their families.
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Echocardiographic parameters are independently associated with rate of renal function decline and progression to dialysis in patients with chronic kidney disease.
Clin J Am Soc Nephrol
PUBLISHED: 10-06-2011
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Cardiac abnormalities were frequently noted in patients with chronic kidney disease (CKD). This study is designed to assess whether echocardiographic parameters are associated with rate of renal function decline and progression to dialysis in CKD stage 3 to 5 patients.
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Prediction of hand strength by hand injury severity scoring system in hand injured patients.
Disabil Rehabil
PUBLISHED: 10-04-2011
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Hand strength is a key component in human hand function, especially to those with strength-required jobs. To evaluate post-injury hand strength, this study was conducted to assess the predictability of hand injury severity scoring (HISS) system to hand strength after a period of recovery.
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Rapid initiation of quetiapine well tolerated as compared with the conventional initiation regimen in patients with schizophrenia or schizoaffective disorders.
Kaohsiung J. Med. Sci.
PUBLISHED: 08-26-2011
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A 2-week, randomized, parallel-group open trial was designed to evaluate the safety and tolerability of a rapid initiation regimen with a higher dose of quetiapine (up to 800 mg/d by Day 4) than that used in the conventional initiation regimen of quetiapine (up to 400mg/d by Day 5) in patients with schizophrenia or schizoaffective disorders. Forty patients were recruited and randomly (3:1) assigned to either the group with rapid initiation of quetiapine or the group with conventional initiation. At the end of the investigation, the difference between the groups in the incidence of adverse events was not significant; a significant drop in the Barnes Akathisia Rating Scale and Simpson-Angus Scale scores was observed only in the group with the rapid initiation regimen. The groups did not differ in terms of improvement on the Clinical Global Impression-Severity of Illness and Positive and Negative Syndrome Scale at the end of the study. The results of our 2-week study suggest that rapid initiation with a higher dose of quetiapine (up to 800 mg/d by Day 4) is well tolerated in patients with schizophrenia or schizoaffective disorders and does not compromise efficacy relative to the conventional initiation.
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Echocardiographic parameters are independently associated with increased cardiovascular events in patients with chronic kidney disease.
Nephrol. Dial. Transplant.
PUBLISHED: 08-03-2011
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Patients with chronic kidney disease (CKD) are associated with increased cardiovascular (CV) morbidity and mortality. Echocardiographic measures of heart structure and function have been reported to predict adverse CV outcomes in various pathologic conditions. The aim of this study is to assess whether echocardiographic parameters are independently associated with increased CV events in patients with CKD Stages 3-5.
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Impaired left ventricular systolic function and increased brachial-ankle pulse-wave velocity are independently associated with rapid renal function progression.
Hypertens. Res.
PUBLISHED: 07-14-2011
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Heart failure and increased arterial stiffness are associated with declining renal function. Few studies have evaluated the association between left ventricular ejection fraction (LVEF) and brachial-ankle pulse-wave velocity (baPWV) and renal function progression. The aim of this study was to assess whether LVEF<40% and baPWV are associated with a decline in the estimated glomerular filtration rate (eGFR) and the progression to a renal end point of ?25% decline in eGFR. This longitudinal study included 167 patients. The baPWV was measured with an ankle-brachial index-form device. The change in renal function was estimated by eGFR slope. The renal end point was defined as ?25% decline in eGFR. Clinical and echocardiographic parameters were compared and analyzed. After a multivariate analysis, serum hematocrit was positively associated with eGFR slope, and diabetes mellitus, baPWV (P=0.031) and LVEF<40% (P=0.001) were negatively associated with eGFR slope. Forty patients reached the renal end point. Multivariate, forward Cox regression analysis found that lower serum albumin and hematocrit levels, higher triglyceride levels, higher baPWV (P=0.039) and LVEF<40% (P<0.001) were independently associated with progression to the renal end point. Our results show that LVEF<40% and increased baPWV are independently associated with renal function decline and progression to the renal end point.
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Laser-induced carotid artery injury model in the rat for therapeutic agent screening.
Lasers Med Sci
PUBLISHED: 06-29-2011
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The aims of this study were to establish a rat model of carotid artery injury and to evaluate its suitability for evaluating therapeutic agents active against endothelial proliferation. Wistar-Kyoto rats were injected intravenously with the photochemically reactive dyes rose bengal or Evans blue, and the carotid artery was then focally irradiated with laser light of the appropriate wavelength. Histological sections of the carotid artery were analyzed to determine the appropriate parameters for this model. Ferulic acid was used to assess the suitability of this model for drug screening. No animal died as a result of the photochemical treatment. Endothelial proliferation in the carotid artery was observed in rats injected with rose Bengal and exposed to green laser light. Ferulic acid (400 mg/kg per day) significantly (p<0.05) reduced endothelial proliferation in the carotid artery 28 days after injury in dye-treated animals compared with vehicle-treated animals. This simple experimental rat model is suitable for studying factors inhibiting endothelial thickening after vessel damage and for developing therapeutic strategies active against endothelial proliferation.
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Inhibition of Japanese encephalitis virus infection by the sulfated polysaccharide extracts from Ulva lactuca.
Mar. Biotechnol.
PUBLISHED: 06-24-2011
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Japanese encephalitis virus (JEV), a neurotropic flavivirus, is one of the major causes of acute encephalitis in humans. After infection, inflammatory reactions and neurological diseases often develop. Still there are no effective drugs available against virus infection. Recently, extracts of algae have been shown to possess a broad range of biological activities including antivirus activity. In this study, we identified that the sulfated polysaccharide extracts from Ulva lactuca can inhibit JEV infection in Vero cells. Mechanistic studies further revealed that the Ulva sulfated polysaccharide extracts can block virus adsorption and thus make the virus unable to enter cells. The Ulva sulfated polysaccharide extracts also effectively decrease the production of pro-inflammatory cytokines in the JEV-infected primary mixed glia cells. In an animal study, the JEV-infected C3H/HeN mice appeared to have neurobehavioral abnormalities on the fifth day and died on the seventh day post infection. However, the JEV-infected mice pretreated with the Ulva sulfated polysaccharide extracts can delay the onset of hind limb paralysis and thereby prevent mice from death.
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Dioscorea nipponica Makino inhibits migration and invasion of human oral cancer HSC-3 cells by transcriptional inhibition of matrix metalloproteinase-2 through modulation of CREB and AP-1 activity.
Food Chem. Toxicol.
PUBLISHED: 06-10-2011
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Oral cancer mortality has increased during the last decade due to the difficulties in treating related metastasis. Dioscorea nipponica Makino, a popular folk medicine, exerts anti-obesity and anti-inflammation properties. However, the effect of this folk medicine on metastasis of oral cancer has yet to be fully elucidated. The present study demonstrates that D. nipponica extracts (DNE), at a range of concentrations (0-50 ?g/mL), concentration-dependently inhibited migration/invasion capacities of human oral cancer cells, HSC-3, without cytotoxic effects. The anti-migration effect of DNE was also observed in two other OSCC cell lines, Ca9-22 and Cal-27. Zymography, real time PCR, and Western blotting analyses revealed that DNE inhibited matrix metalloproteinase-2 (MMP-2) enzyme activity, and RNA and protein expression. The inhibitory effects of DNE on MMP-2 proceeded by up-regulating tissue inhibitor of metalloproteinase-2 (TIMP-2), as well as suppressing nuclear translocation and DNA binding activity of cAMP response element-binding (CREB) and activating protein-1 (AP-1) on the MMP-2 promoter in HSC-3 cells. In conclusion, DNE inhibited the invasion of oral cancer cells and may have potential use as a chemopreventive agent against oral cancer metastasis.
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The treatment of bladder cancer in a mouse model by epigallocatechin-3-gallate-gold nanoparticles.
Biomaterials
PUBLISHED: 05-31-2011
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(--)-Epigallocatechin-3-gallate (EGCG), an active ingredient in green tea, was known to effectively inhibit formation and development of tumors. However, excessive uptake of EGCG was also known to cause cytotoxicity to normal cells. In this study, EGCGs that were physically attached onto the surface of nanogold particles (pNG) was confirmed by scanning electron microscopy. The anticancer activity of the EGCG-adsorbed pNG was investigated in C3H/HeN mice subcutaneously implanted with MBT-2 murine bladder tumor cells. EGCG-pNG was confirmed to inhibit tumor cell growing by means of cell apoptosis. The mechanism that EGCG-pNG mediates tumor apoptosis was uncovered to activate the caspase cascade through the Bcl-family proteins in the mitochondrial pathway. Additionally, the mechanism that tumors were suppressed by injecting EGCG-pNG directly into the tumor site was determined to be through downregulation of VEGF, whereas that by oral administration of EGCG was through reversing immune suppression upon cancer progression. In this assessment, the prepared EGCG-pNG was confirmed to be more effective than free EGCG in inhibiting bladder tumor in model mice.
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A genetic polymorphism (rs17251221) in the calcium-sensing receptor gene (CASR) is associated with stone multiplicity in calcium nephrolithiasis.
PLoS ONE
PUBLISHED: 05-17-2011
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Calcium nephrolithiasis is one of the most common causes of renal stones. While the prevalence of this disease has increased steadily over the last 3 decades, its pathogenesis is still unclear. Previous studies have indicated that a genetic polymorphism (rs17251221) in the calcium-sensing receptor gene (CASR) is associated with the total serum calcium levels. In this study, we collected DNA samples from 480 Taiwanese subjects (189 calcium nephrolithiasis patients and 291 controls) for genotyping the CASR gene. Our results indicated no significant association between the CASR polymorphism (rs17251221) and the susceptibility of calcium nephrolithiasis. However, we found a significant association between rs17251221 and stone multiplicity. The risk of stone multiplicity was higher in patients with the GG+GA genotype than in those with the AA genotype (chi-square test: P?=?0.008; odds ratio ?=? 4.79; 95% confidence interval, 1.44-15.92; Yates correction for chi-square test: P?=?0.013). In conclusion, our results provide evidence supporting the genetic effects of CASR on the pathogenesis of calcium nephrolithiasis.
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Prevalence of musculoskeletal disorders and job exposure in Taiwan oyster shuckers.
Am. J. Ind. Med.
PUBLISHED: 05-11-2011
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Oyster shucking is characterized by long hours of static work, awkward working posture, and highly repetitive hand/wrist motion. The objectives of this study were to investigate the prevalence of musculoskeletal discomfort and kyphosis in oyster shuckers in Taiwan as well as the biomechanical features of oyster shucking.
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Stepwise increases in left ventricular mass index and decreases in left ventricular ejection fraction correspond with the stages of chronic kidney disease in diabetes patients.
Exp Diabetes Res
PUBLISHED: 05-09-2011
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Patients with diabetic nephropathy are reported to have a high prevalence of left ventricular structural and functional abnormalities. This study was designed to assess the determinants of left ventricular mass index (LVMI) and left ventricular ejection fraction (LVEF) in diabetic patients at various stages of chronic kidney disease (CKD).
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The initial anatomical severity in patients with hand injuries predicts future health-related quality of life.
J Trauma
PUBLISHED: 05-04-2011
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There have been no rigorous studies exploring whether the severity of hand injury can predict health-related quality of life (HRQoL). The purpose of our study is to examine the relationship between the initial anatomic severity of hand injuries (evaluated by the Hand Injury Severity Scoring [HISS] system) and HRQoL in patients with hand injuries.
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Relationship of interleukin-8 gene polymorphisms with hepatocellular carcinoma susceptibility and pathological development.
J Surg Oncol
PUBLISHED: 05-03-2011
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Hepatocellular carcinoma (HCC) is one of the most frequent malignant neoplasms worldwide, and the second leading cause of death from cancer in Taiwan. Interleukin-8 (IL-8) is an angiogenic chemokine with important roles in the development and progression of many human malignancies including HCC. This study investigates the effects of single-nucleotide polymorphisms (SNPs) in the IL-8 gene on the susceptibility and clinicopathological characteristics of HCC.
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Brachial-ankle pulse wave velocity and rate of renal function decline and mortality in chronic kidney disease.
Clin J Am Soc Nephrol
PUBLISHED: 03-31-2011
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Increased arterial stiffness was reported to be associated with decreased estimated GFR (eGFR). Previous studies suggested that arterial stiffness might play a role in renal function progression in patients with chronic kidney disease (CKD). The aim of this study was to investigate whether there was an independent association between brachial-ankle pulse wave velocity (baPWV), a marker of arterial stiffness, and renal function progression in CKD patients.
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Antibodies against Helicobacter pylori heat shock protein 60 aggravate HSP60-mediated proinflammatory responses.
Cytokine
PUBLISHED: 03-29-2011
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Anti-Helicobacter pylori heat shock protein 60 (HpHSP60) antibodies are usually found in H. pylori-infected patients and are known to be associated with the progression of gastric diseases. However, the effects of these antibodies on the functions of HpHSP60 have not been identified. This study aims to investigate the effects of the interaction between anti-HSP60 antibodies and HpHSP60 on inflammatory responses. Anti-HpHSP60 polyclonal sera and monoclonal antibodies (mAbs) were produced to evaluate their effects on HpHSP60-induced IL-8 and TNF-? activity. The results indicated that anti-HpHSP60 polyclonal sera collected from patients infected with H. pylori or from rabbit and mice immunized with HpHSP60 could significantly enhance HpHSP60-mediated IL-8 and TNF-? secretion from monocytic THP-1 cells. Similar effects were also found with anti-HpHSP60 mAbs. Further analysis revealed that this phenomenon was only carried out by anti-HpHSP60 antibody but not by other non-specific mAbs. Moreover, the non-specific mAbs decreased the synergism of HpHSP60 and anti-HpHSP60 mAbs in proinflammatory cytokine induction. Herein, we have examined the role of anti-HpHSP60 antibody in host immune responses for the first time. This study demonstrated that H. pylori HSP60/mAbs could modulate helicobacterial pathogenesis by increasing IL-8 and TNF-? production. The pathogen-specific antibodies may execute potential immune functions rather than recognize or neutralize microbes.
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Modulation of the immune-related gene responses to protect mice against Japanese encephalitis virus using the antimicrobial peptide, tilapia hepcidin 1-5.
Biomaterials
PUBLISHED: 03-14-2011
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Japanese encephalitis virus (JEV), a neurotropic flavivirus, is one of the major causes of acute encephalitis in humans. After infection, it is commonly associated with inflammatory reactions and neurological disease. There is still no effective antiviral drug available against Japanese encephalitis virus infection. Recently, a number of investigators found that antimicrobial peptide (AMPs) present a broad range of biological activities including antimicrobial and immunomodulatory activities. In this study, we found that an AMP, tilapia hepcidin (TH)1-5, caused no harm to either cells or test animals during the test course and could control JEV viral infection in BHK-21 cells. Mice co-injected with TH1-5/JEV and subsequently subjected to JEV re-challenge survived and behaved normally. The neuroprotective effects were associated with marked decreases in: (i) the viral load and viral replication within the brain, (ii) neuronal death, and (iii) secondary inflammation resulting from microglial activation. TH1-5 was also determined to enhance adaptive immunity by elevating levels of anti-JEV-neutralizing antibodies in the serum. The microarray data also showed that TH1-5 modulated Socs-6, interleukin (IL)-6, Toll-like receptor (TLR)-1, TLR-7, caspase-4, interferon (IFN)-?1, ATF-3, and several immune-responsive genes to protect mice against JEV infection. In addition, TH1-5 was confirmed to modulate the expressions of several proinflammatory and immune-responsive genes, such as IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, tumor necrosis factor (TNF)-?, IFN-? and monocyte chemoattractant protein (MCP)-1 at both the transcriptional and translational levels in JEV-infected mice. In conclusion, our findings provide mechanistic insights into the actions of TH1-5 against JEV. Results from our in vivo and in vitro experiments clearly indicate that TH1-5 has antiviral, neuroprotective, anti-inflammatory, and immunomodulatory activities. Furthermore, TH1-5 successfully reduced the severity of disease induced by JEV. Our results point out that TH1-5 is a promising candidate for further development as an antiviral agent against JEV infection.
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Improving cachectic symptoms and immune strength of tumour-bearing mice in chemotherapy by a combination of Scutellaria baicalensis and Qing-Shu-Yi-Qi-Tang.
Eur. J. Cancer
PUBLISHED: 03-09-2011
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Cancer cachexia is characterised by the loss of body mass and directly compromises immune response and the quality of life of cancer patients. In the present study, we set out to investigate the role of Chinese herbs as anticancer medicines and/or chemotherapeutic adjuvants to increase therapeutic efficacy and/or ameliorate given side-effects in animal model.
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The rs1014290 polymorphism of the SLC2A9 gene is associated with type 2 diabetes mellitus in Han Chinese.
Exp Diabetes Res
PUBLISHED: 02-22-2011
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The SLC2A9 gene encodes the glucose transporter 9, with the abilities of transporting both glucose and uric acid and is involved in the pancreatic glucose-stimulated insulin secretion. The single nucleotide polymorphisms (SNPs) of SLC2A9 accounted for 5% variance of serum uric acid (UA). UA was identified as a risk factor for type 2 diabetes mellitus (DM). We investigated whether the SLC2A9 gene variations are associated with type 2 DM in Han Chinese.
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Epigallocatechin-3-gallate effectively attenuates skeletal muscle atrophy caused by cancer cachexia.
Cancer Lett.
PUBLISHED: 02-15-2011
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Cachexia, also known as wasting syndrome notably with skeletal muscle atrophy, costs nearly one-third of all cancer deaths in man. (-)-Epigallocatechin-3-gallate (EGCG), the principal polyphenolic component in green tea, is a potent preventive against cachexia as well as cancers. However, how EGCG counteracts cachexia-provoked muscle wasting is unclear. EGCG was demonstrated to be able to retard tumor progression as well as to prevent body weight from loss, because EGCG attenuates skeletal muscle leukocytic infiltration and down-regulates tumor-induced NF-?B and E3-ligases in muscle. In mice, the dosages optimized against cachexia were determined to be 0.2 mg/mouse/day for prevention and to be 0.6 mg/mouse/day for treatment. Anti-cachexia effects were assessed using the LLC tumor model. Mice with the same body weight were divided into groups, including control, tumor bearing, and tumor-bearing but receiving water or EGCG in both prevention and treatment experiments. RT-PCR was used to assess mRNA expressions of NF-?B, MuRF 1, and MAFbx. The intracellular NF-?B, MuRF 1 and MAFbx were determined and quantified by immunofluorescence and Western blotting, respectively. Our results conclude EGCG regulates the expressions of NF-?B as well as downstream mediators, MuRF 1 and MAFbx, so EGCG may be an appropriate agent to be included in ensemble therapeutics of the tumor-induced muscle atrophy.
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Inhibition of Lipopolysaccharide (LPS)-induced inflammatory responses by Sargassum hemiphyllum sulfated polysaccharide extract in RAW 264.7 macrophage cells.
J. Agric. Food Chem.
PUBLISHED: 02-15-2011
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Sargassum hemiphyllum , a kind of brown seaweed generally found along coastlines in East Asia, has long served as a traditional Chinese medicine. S. hemiphyllum has shown an anti-inflammatory effect; however, its mechanism has not been elucidated clearly. This study explored S. hemiphyllum for its biomedical effects. S. hemiphyllum sulfated polysaccharide extract (SHSP) was first prepared; the mouse macrophage cell line (RAW 264.7) activated by lipopolysaccharide (LPS) was used as a model system. The secretion profiles of pro-inflammatory cytokines, including IL-1?, IL-6, TNF-?, and NO, were found significantly to be reduced in 1-5 mg/mL dose ranges of SHSP treatments. RT-PCR analysis suggested SHSP inhibits the LPS-induced mRNA expressions of IL-?, iNOS, and COX-2 in a dose-dependent manner. At protein levels, Western blot analysis demonstrated a similar result for NF-?B (p65) in cytosol/nuclear. Taken together, the anti-inflammatory properties of SHSP may be attributed to the down-regulation of NF-?B in nucleus.
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Passive immune-protection of small abalone against Vibrio alginolyticus infection by anti-Vibrio IgY-encapsulated feed.
Fish Shellfish Immunol.
PUBLISHED: 01-24-2011
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Small abalone (Haliotis diversicolor supertexta) is a high value-added shellfish. It however has been suffering Vibrio alginolyticus infections, which cause mass death of small abalone and thus great economic losses, particularly in artificial aquaculture. In this study, we attempted to treat small abalone with anti-Vibrio IgY to elicit a passive immunity directly against V. alginolyticus infections. Anti-Vibrio IgY was alginate encapsulated in egg powders as feed, which may avoid antibody inactivation in the gastrointestinal tract of small abalone. The feed was tested for the stability of anti-Vibrio IgY in a gastrointestinal mimic environment. The result showed anti-Vibrio IgY retained activity as high as 90% after 4 h exposure to pancreatic enzymes. Addition of 0, 5 or 10% anti-Vibrio IgY-encapsulated egg powders into a basal diet to form abalone diet formulae. Small abalones fed with the anti-Vibrio IgY formulae showed a relatively high respiratory burst activity than those without anti-Vibrio IgY treatments. The survival rates of small abalones fed with 5 or 10% anti-Vibrio IgY egg powders were in the range of 65-70% 14 days post-V. alginolyticus challenge (1 x 10? c.f.u.), which was significantly higher than 0% of those fed without anti-Vibrio IgY. The anti-Vibrio IgY-encapsulated formulae were thus concluded to be an effective means to prevent small abalone from V. alginolyticus infection, and may be practical in use in abalone aquaculture.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.