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Find video protocols related to scientific articles indexed in Pubmed.
Biomechanical Analysis of Differential Pullout Strengths of Bone Screws using Cervical Anterior Transpedicular Technique (ATPS) in normal and Osteoporotic Cervical Cadaveric Spines.
Spine
PUBLISHED: 10-25-2014
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Study Design. Biomechanical in vitro studyObjective. To determine whether the peak pullout force (PPF) of Anterior Cervical Transpedicular Screw (ATPS) fixed in osteoporotic vertebrae positively influence screw stability or not before and after fatigue.Summary of Background Data. Multilevel cervical spine procedures with osteoporosis can challenge the stability of current screw-and-plate systems. A second surgical posterior approach is coupled with potential risks of increased morbidity and complications. Hence, anterior cervical instrumentation that increases primary construct stability, while avoiding the need for posterior augmentation, would be valuable.Methods. Sixty formalin-fixed vertebrae at different levels were randomly selected. The vertebrae were divided into healthy controls (group A1, A2), osteoporotic controls (B1, B2), healthy ATPS groups (C1, C2), osteoporotic ATPS groups (D1, D2) and osteoporotic restoration controls (E1, E2). The procedure of ATPS insertion was simulated with 2 pilot holes being drilled on each side of 20 vertebral bodies that were implanted with either vertebral screw or PMMA. Each side randomly received either instant PPF or PPF beyond fatigue (2.5 Hz; 20,000 times).Results. The pre-fatigue PPFs were significantly higher than the post-fatigue PPFs in all groups (group A: 366.06±58.78 vs. 248.93±57.21N; group B: 275.58±23.18 vs. 142.79±44.78 N; group C: 635.99±185.28 vs. 542.57±136.58N; group D: 519.22±122.12 vs. 393.16±192.07N, and group E: 431.78±75.77 vs. 325.74±95.10 N). The post-fatigue PPFs were reduced by 32.00% (group A), 48.19% (group B), 14.69% (group C), 24.28% (group D) and 24.72% (group E). The acute and post-fatigue PPFs of both control groups were significantly lower than that of ATPS groups (P<0.05). The cyclic osteoporosis ATPS group achieved the same PPF compared to the vertebral restoration screw (VBRS) group.Conclusions. The findings of this study suggest that instant PPF and fatigue resistance capability of an ATPS fixation were significantly better than other control groups, especially in the osteoporotic vertebrae.
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[Sling suspension: a new technique of treating uterine prolapse].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-26-2014
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To report a novel surgical technique of laparoscopic extraperitoneal sling suspension for uterine prolapse and evaluate its efficacy.
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Fucoxanthin induces apoptosis in human cervical cancer cell line HeLa via PI3K/Akt pathway.
Tumour Biol.
PUBLISHED: 08-13-2014
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Cervical cancer (CC) is a malignant neoplasm arising from cells originating in the cervix uteri, among the top causes of death from cancer in women. In a gene expression profiling study of metabolic response to treatment, PI3K/Akt signaling pathway are associated with the development of CC. A common mechanism of Akt activation seen in cancer types is alterations in the upstream regulators of Akt such as phosphatidylinositol 3-kinase (PI3K), which is overexpressed in cervical cancer tissues, and leads to phosphorylation of Akt. Both PI3K and Akt inhibitors exist and may be therapeutically valuable. In the present study, we use MTT assay and western blot for the high-throughput screening to select specific inhibitors of PI3K/Akt signaling pathway, and then obtain fucoxanthin. Fucoxanthin is a water-soluble dietary fiber, taken from the unique slimy component of alginic cells. Various studies have pointed out that fucoxanthin is very effective for the treatment of cancer. Our results have shown that fucoxanthin induced a significant apoptosis of HeLa cells, compared with other candidates. After treatment with fucoxanthin for 24 h, the level of phosphorylation was inhibited in a dose-dependent manner, and the proteins of apoptotic markers were changed in HeLa cells. And fucoxanthin could suppress tumor growth in vivo. In addition, the mitochondrial signal transduction pathway maybe was involved in its mechanism and NF-?B activation was decreased after treatment with fucoxanthin. Therefore, fucoxanthin may be used as anti-cervical cancer drugs in the future.
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miR-193a-3p regulates the multi-drug resistance of bladder cancer by targeting the LOXL4 gene and the Oxidative Stress pathway.
Mol. Cancer
PUBLISHED: 07-10-2014
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Chemoresistance is a major obstacle to the curative cancer chemotherapy and presents one of the most formidable challenges in both research and management of cancer.
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Phosphorylation of CDK2 on threonine 160 influences silencing of sex chromosome during male meiosis.
Biol. Reprod.
PUBLISHED: 04-23-2014
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In mammalian meiosis, the X and Y chromosomes are largely unsynapsed and transcriptionally silenced during the pachytene stage of meiotic prophase (meiotic sex chromosome inactivation), forming a specialized nuclear territory called sex or XY body. An increasing number of proteins and noncoding RNAs were found to localize to the sex body and take part in influencing expression of sex chromosome genes. Cyclin-dependent kinase 2 (Cdk2 (-/-)) spermatocytes show incomplete sex chromosome pairing. Here, we further showed that phosphorylation of CDK2 isoform 1 (p-CDK2(39) [39 kDa]) on threonine 160 localizes to the sites of asynapsis and the sex body, interacting with phosphorylated gamma-H2AX. Meanwhile, p-CDK2(39) is frequently mislocalized throughout the sex body, and meiotic sex chromosome inactivation is disrupted in PWK×C57BL/6J hybrid mice. Furthermore, pachytene spermatocytes treated with mevastatin (an inhibitor of p-CDK2) showed overexpression of sex chromosome-linked genes. Our results highlight an important role for p-CDK2(39) in influencing silencing of the sex chromosomes during male meiosis by interacting with gamma-H2AX.
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Phosphorylation of CDK2 at threonine 160 regulates meiotic pachytene and diplotene progression in mice.
Dev. Biol.
PUBLISHED: 03-31-2014
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Telomere clustering is a widespread phenomenon among eukaryotes. However, the molecular mechanisms that regulate formation of telomere clustering in mammalian meiotic prophase I, are still largely unknown. Here, we show that CDK2, especially p39(cdk2), as a potential meiosis-specific connector interaction with SUN1 mediates formation of telomere clustering during mouse meiosis. The transition from CDK2 to p-CDK2 also regulates the progression from homologous recombination to desynapsis by interacting with MLH1. In addition, disappearance of CDK2 on the telomeres and of p-CDK2 on recombination sites, were observed in Sun1(-/-) mice and in pachytene-arrested hybrid sterile mice (pwk×C57BL/6 F1), respectively. These results suggest that transition from CDK2 to p-CDK2 plays a critical role for regulating meiosis progression.
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Comparison of laparoscopic peritoneal vaginoplasty and sigmoid colon vaginoplasty performed during radical surgery for primary vaginal carcinoma.
World J Surg Oncol
PUBLISHED: 03-03-2014
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Radical surgery of primary vaginal carcinoma typically involves partial or complete resection of the vagina, and young patients in particular can experience sexual dysfunction after surgery. Vaginoplasty is mandatory for this population, multiple vaginal reconstructive techniques have been reported. Here we attempted to determine whether the peritoneum is a feasible alternative to the sigmoid colon in vaginoplasty performed during radical surgery.
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Studying the nucleated mammalian cell membrane by single molecule approaches.
PLoS ONE
PUBLISHED: 01-01-2014
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The cell membrane plays a key role in compartmentalization, nutrient transportation and signal transduction, while the pattern of protein distribution at both cytoplasmic and ectoplasmic sides of the cell membrane remains elusive. Using a combination of single-molecule techniques, including atomic force microscopy (AFM), single molecule force spectroscopy (SMFS) and stochastic optical reconstruction microscopy (STORM), to study the structure of nucleated cell membranes, we found that (1) proteins at the ectoplasmic side of the cell membrane form a dense protein layer (4 nm) on top of a lipid bilayer; (2) proteins aggregate to form islands evenly dispersed at the cytoplasmic side of the cell membrane with a height of about 10-12 nm; (3) cholesterol-enriched domains exist within the cell membrane; (4) carbohydrates stay in microdomains at the ectoplasmic side; and (5) exposed amino groups are asymmetrically distributed on both sides. Based on these observations, we proposed a Protein Layer-Lipid-Protein Island (PLLPI) model, to provide a better understanding of cell membrane structure, membrane trafficking and viral fusion mechanisms.
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Simplified process model discovery based on role-oriented genetic mining.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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Process mining is automated acquisition of process models from event logs. Although many process mining techniques have been developed, most of them are based on control flow. Meanwhile, the existing role-oriented process mining methods focus on correctness and integrity of roles while ignoring role complexity of the process model, which directly impacts understandability and quality of the model. To address these problems, we propose a genetic programming approach to mine the simplified process model. Using a new metric of process complexity in terms of roles as the fitness function, we can find simpler process models. The new role complexity metric of process models is designed from role cohesion and coupling, and applied to discover roles in process models. Moreover, the higher fitness derived from role complexity metric also provides a guideline for redesigning process models. Finally, we conduct case study and experiments to show that the proposed method is more effective for streamlining the process by comparing with related studies.
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A Toxin-Antitoxin Module of Salmonella Promotes Virulence in Mice.
PLoS Pathog.
PUBLISHED: 12-01-2013
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Toxin-antitoxin (TA) modules are widely prevalent in both bacteria and archaea. Originally described as stabilizing elements of plasmids, TA modules are also widespread on bacterial chromosomes. These modules promote bacterial persistence in response to specific environmental stresses. So far, the possibility that TA modules could be involved in bacterial virulence has been largely neglected, but recent comparative genomic studies have shown that the presence of TA modules is significantly associated with the pathogenicity of bacteria. Using Salmonella as a model, we investigated whether TA modules help bacteria to overcome the stress conditions encountered during colonization, thereby supporting virulence in the host. By bioinformatics analyses, we found that the genome of the pathogenic bacterium Salmonella Typhimurium encodes at least 11 type II TA modules. Several of these are conserved in other pathogenic strains but absent from non-pathogenic species indicating that certain TA modules might play a role in Salmonella pathogenicity. We show that one TA module, hereafter referred to as sehAB, plays a transient role in virulence in perorally inoculated mice. The use of a transcriptional reporter demonstrated that bacteria in which sehAB is strongly activated are predominantly localized in the mesenteric lymph nodes. In addition, sehAB was shown to be important for the survival of Salmonella in these peripheral lymphoid organs. These data indicate that the transient activation of a type II TA module can bring a selective advantage favouring virulence and demonstrate that TA modules are engaged in Salmonella pathogenesis.
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Noncontiguous lumbar vertebral hemangiomas treated by posterior decompression, intraoperative kyphoplasty, and segmental fixation.
J Neurosurg Spine
PUBLISHED: 11-15-2013
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Vertebral hemangiomas are benign lesions and are often asymptomatic. Most vertebral hemangiomas that cause cord compression and neurological symptoms are located in the thoracic spine and involve a single vertebra. The authors report the rare case of lumbar hemangiomas in a 60-year-old woman presenting with severe back pain and rapidly progressive neurological signs attributable to 2 noncontiguous lesions. After embolization of the feeding arteries, no improvement was noted. Thus, the authors performed open surgery using a combination of posterior decompression, intraoperative kyphoplasty, and segmental fixation. The patient experienced relief from back and leg pain immediately after surgery. At 3 months postoperatively, her symptoms and neurological deficits had improved completely. To the authors knowledge, this is the first description of 2 noncontiguous extensive lumbar hemangiomas presenting with neurological symptoms managed by such combined treatment. The combined management seems to be an effective method for treating symptomatic vertebral hemangiomas.
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Snail family proteins in cervical squamous carcinoma: expression and significance.
Clin Invest Med
PUBLISHED: 08-01-2013
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Epithelial-mesenchymal transition (EMT) is crucial for tumor progression and metastasis. Snail family members, including Snail, Slug and Smuc, are the transcription factors that repress E-cadherin expression and induce epithelial-mesenchymal transition in some tumor tissues. In this study, the expression of snail family proteins in cervical squamous cancers was evaluated.
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Pedicle Screw Combined with Lateral Mass Screw Fixation in the Treatment of Basilar Invagination and Congenital C2-3 Fusion.
J Spinal Disord Tech
PUBLISHED: 05-24-2013
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Clinical evaluation of a surgical fixation technique featuring combined use of pedicle screw and lateral mass screw.
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Totally cystic schwannoma of the lumbar spine.
Orthopedics
PUBLISHED: 05-16-2013
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A schwannoma is a benign tumor arising from a schwann cell and occurs mainly in the nerve sheath in the intradural extramedullary region. Schwannomas have been well described as occurring in the lumbar spine, but total cystic degeneration of schwannomas is rarely reported. The authors describe the clinical and radiographic evaluations and treatment of a rare case of an intraextradural totally cystic schwannoma on the lumbar spine.Two patients reported a history of 6 to 12 months of pain accompanied by weakness in the lower extremities. On examination, 1 patient had bilateral lower-extremity muscle strength graded at 4/5, and magnetic resonance imaging revealed a cystic schwannoma (1.5 × 2.0 cm in the sagittal dimension) at L2-L3. The other patient had a right lower-extremity muscle strength graded at 3/5, and magnetic resonance imaging revealed a cystic schwannoma (2.0 × 3.0 cm in the sagittal dimension) at L4-L5. The patients underwent operative treatment, and the tumors were completely removed, as were the filum terminale adhered to the tumor. Pedicle screws were used to maintain stability of the lumbar spine. Gross examination of the tumors showed yellowish-white soft contents. Histologic examination confirmed that they were benign totally cystic schwannomas. Postoperatively, the patients neurologic symptoms completely resolved.Cystic schwannomas can be diagnosed using preoperative magnetic resonance imaging. The filum terminale cut off the tumor walls did not cause the clinical symptoms in the 2 patients.
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A single-molecule force spectroscopy study of the interactions between lectins and carbohydrates on cancer and normal cells.
Nanoscale
PUBLISHED: 03-11-2013
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The interaction forces between carbohydrates and lectins were investigated by single-molecule force spectroscopy on both cancer and normal cells. The binding kinetics was also studied, which shows that the carbohydrate-lectin complex on cancer cells is less stable than that on normal cells.
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Dual-factor triggered fluorogenic nanoprobe for ultrahigh contrast and subdiffraction fluorescence imaging.
Biomaterials
PUBLISHED: 03-10-2013
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Ultrahigh contrast fluorescence molecular imaging has long been pursued over the past few decades from basic sciences to clinics. Although new classes of near-infrared (NIR) molecular probes are emerging, the requirement of fluorophores with high quantum yield, high signal to noise (S/N) ratio, and being activatable to microenvironment changes can hardly be fulfilled. In this study, a new NIR dye embedded fluorogenic nanoprobe (fg-nanoprobe) was developed for ultrahigh contrast in vitro and in vivo imaging with negligible background interference. The achieved S/N ratio was found to be attributed to the synergistic effects of the cellular compartmental triggered fluorogenicity and pH tunable fluorescence on/off character. In addition, this constructed fluorogenic nanoprobe could be coupled with image processing method for super-resolution subdiffraction imaging. The developed fg-nanoprobe integrated photophysical merits of the synthesized NIR fluorophore and advantages of engineered nanoparticle for enhanced fluorescence molecular imaging. This probe may open another avenue for ultrahigh contrast fluorescence molecular imaging in the future.
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Detection of carbohydrates on the surface of cancer and normal cells by topography and recognition imaging.
Chem. Commun. (Camb.)
PUBLISHED: 02-13-2013
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Galactose was detected and localized on the surface of cancer and normal cells by topography and recognition imaging at the single molecular level. There are more galactoses on cancer cells than on normal cells. The stability of galactose-lectin on cancer cells is much lower than that on normal cells.
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Evaluation of Helicobacter pylori eradication and drug therapy in patients with functional dyspepsia.
Exp Ther Med
PUBLISHED: 02-06-2013
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The aim of this study was to assess the effect of Helicobactor pylori (H. pylori) infection and drug therapy on functional dyspepsia (FD) symptoms and gastrointestinal eosinophil count. In this study, 215 continuous FD patients fulfilling Rome III criteria were enrolled. The patients were divided into a H. pylori-positive group and a H. pylori-negative group. The H. pylori-positive group was divided into H. pylori-eradicated and H. pylori-uneradicated groups following H. pylori-eradication treatment, and the H. pylori-negative group was randomly divided into esomeprazole and teprenone treatment groups. The symptom scores of the esomeprazole group were significantly lower compared with those of the teprenone group at week 6 but not at baseline and week 2. Compared with the H. pylori-uneradicated group, eosinophil counts in the antrum and body were significantly reduced in the H. pylori-eradicated group at week 6. The number of gastric eosinophil clusters was significantly higher in the H. pylori-positive group than in the H. pylori-negative group. Eradication was associated with gastric eosinophil counts but did not affect duodenal eosinophil levels. Neither esomeprazole nor teprenone treatments reduced eosinophil levels in the stomach and duodenum of H. pylori-negative patients.
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Construction and accuracy assessment of patient-specific biocompatible drill template for cervical anterior transpedicular screw (ATPS) insertion: an in vitro study.
PLoS ONE
PUBLISHED: 01-10-2013
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With the properties of three-column fixation and anterior-approach-only procedure, anterior transpedicular screw (ATPS) is ideal for severe multilevel traumatic cervical instabilities. However, the accurate insertion of ATPS remains challenging. Here we constructed a patient-specific biocompatible drill template and evaluated its accuracy in assisting ATPS insertion.
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In Vivo Identification and Characterization of CD4(+) Cytotoxic T Cells Induced by Virulent Brucella abortus Infection.
PLoS ONE
PUBLISHED: 01-01-2013
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CD4(+) T cells display a variety of helper functions necessary for an efficient adaptive immune response against bacterial invaders. This work reports the in vivo identification and characterization of murine cytotoxic CD4(+) T cells (CD4(+) CTL) during Brucella abortus infection. These CD4(+) CTLs express granzyme B and exhibit immunophenotypic features consistent with fully differentiated T cells. They express CD25, CD44, CD62L ,CD43 molecules at their surface and produce IFN-?. Moreover, these cells express neither the co-stimulatory molecule CD27 nor the memory T cell marker CD127. We show here that CD4(+) CTLs are capable of cytolytic action against Brucella-infected antigen presenting cells (APC) but not against Mycobacterium-infected APC. Cytotoxic CD4(+) T cell population appears at early stages of the infection concomitantly with high levels of IFN-? and granzyme B expression. CD4(+) CTLs represent a so far uncharacterized immune cell sub-type triggered by early immune responses upon Brucella abortus infection.
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Targeting of histone deacetylases to reactivate tumour suppressor genes and its therapeutic potential in a human cervical cancer xenograft model.
PLoS ONE
PUBLISHED: 01-01-2013
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Aberrant histone acetylation plays an essential role in the neoplastic process via the epigenetic silencing of tumour suppressor genes (TSGs); therefore, the inhibition of histone deacetylases (HDAC) has become a promising target in cancer therapeutics. To investigate the correlation of histone acetylation with clinicopathological features and TSG expression, we examined the expression of acetylated H3 (AcH3), RAR?2, E-cadherin, and ?-catenin by immunohistochemistry in 65 cervical squamous cell carcinoma patients. The results revealed that the absence of AcH3 was directly associated with poor histological differentiation and nodal metastasis as well as reduced/negative expression of RAR?2, E-cadherin, and ?-catenin in clinical tumour samples. We further demonstrated that the clinically available HDAC inhibitors valproic acid (VPA) and suberoylanilide hydroxamic acid (SAHA), in combination with all-trans retinoic acid (ATRA), can overcome the epigenetic barriers to transcription of RAR?2 in human cervical cancer cells. Chromatin immunoprecipitation analysis showed that the combination treatment increased the enrichment of acetylated histone in the RAR?2-RARE promoter region. In view of these findings, we evaluated the antitumor effects induced by combined VPA and ATRA treatment in a xenograft model implanted with poorly differentiated human squamous cell carcinoma. Notably, VPA restored RAR?2 expression via epigenetic modulation. Additive antitumour effects were produced in tumour xenografts by combining VPA with ATRA treatment. Mechanistically, the combination treatment reactivated the expression of TSGs RAR?2, E-cadherin, P21 (CIP1) , and P53 and reduced the level of p-Stat3. Sequentially, upregulation of involucrin and loricrin, which indicate terminal differentiation, strongly contributed to tumour growth inhibition along with partial apoptosis. In conclusion, targeted therapy with HDAC inhibitors and RAR?2 agonists may represent a novel therapeutic approach for patients with cervical squamous cell carcinoma.
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Magnetospira thiophila gen. nov., sp. nov., a marine magnetotactic bacterium that represents a novel lineage within the Rhodospirillaceae (Alphaproteobacteria).
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 11-25-2011
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A marine, magnetotactic bacterium, designated strain MMS-1(T), was isolated from mud and water from a salt marsh in Woods Hole, Massachusetts, USA, after enrichment in defined oxygen-concentration/redox-gradient medium. Strain MMS-1(T) is an obligate microaerophile capable of chemoorganoheterotrophic and chemolithoautotrophic growth. Optimal growth occurred at pH 7.0 and 24-26 °C. Chemolithoautotrophic growth occurred with thiosulfate as the electron donor and autotrophic carbon fixation was via the Calvin-Benson-Bassham cycle. The G+C content of the DNA of strain MMS-1(T) was 47.2 mol%. Cells were Gram-negative and morphologically variable, with shapes that ranged from that of a lima bean to fully helical. Cells were motile by means of a single flagellum at each end of the cell (amphitrichous). Regardless of whether grown in liquid or semi-solid cultures, strain MMS-1(T) displayed only polar magnetotaxis and possessed a single chain of magnetosomes containing elongated octahedral crystals of magnetite, positioned along the long axis of the cell. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain MMS-1(T) belongs to the family Rhodospirillaceae within the Alphaproteobacteria, and is distantly related to species of the genus Magnetospirillum. Strain MMS-1(T) is therefore considered to represent a novel species of a new genus, for which the name Magnetospira thiophila gen. nov., sp. nov. is proposed. The type strain of Magnetospira thiophila is MMS-1(T) (?=?ATCC BAA-1438(T)?=?JCM 17960(T)).
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[Optimization of plant des-pGlu1-Brazzein gene according to yeasty biased codons and its expression in Pichia pastoris].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 11-22-2011
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According to the amino acid sequence of des-pGlu1-Brazzein, 4 pairs of oligonucleotide with cosmic site were synthesized by using yeasty biased codons. After linkage and PCR, the 179 bp code area of des-pGlu1-Brazzein was obtained and inserted into pPIC9K, which resulted in the recombinant expression vector pPIC9K-Bra. By digestion with Sal I, the lined pPIC9K-Bra was transformed into Pichia pastoris GS115 by electric shock. The results of expression indicted that the secreted target protein accounted for 51.6% of total protein in the supernatant and showed biological activity after purification.
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Metatranscriptomic signature of exogenous polyamine utilization by coastal bacterioplankton.
Environ Microbiol Rep
PUBLISHED: 09-19-2011
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The polyamines putrescine (PUT) and spermidine (SPD) are ubiquitous in seawater, but mechanisms that drive the degradation of these important nitrogen sources by marine bacteria remain unclear. We employed a comparative metatranscriptomics approach to compare gene transcription patterns between coastal bacterioplankton communities with and without amendments of PUT or SPD, in an effort to understand how bacterial communities and their genes shape polyamine biogeochemistry in the ocean. Statistically different transcript categories in the PUT (25 COG groups) and SPD (23 COG groups) samples, relative to controls that received no amendment (CTRL), indicated that genes encoding the cellular translation machinery and the metabolism of organic nitrogen and carbon became enriched in the community transcriptome when polyamine availability increased. Of the three known pathways for bacterial polyamine degradation, only genes in the transamination pathway were enriched in the PUT and SPD libraries, suggesting that this route dominated polyamine degradation. Taxonomic affiliation of significantly enriched diagnostic genes in the PUT and SPD libraries pointed to roseobacter- and SAR11-affiliated bacteria as the predominant taxa driving transformation in this coastal ocean, although other diverse marine bacterioplankton groups (Gammaproteobacteria, Betaproteobacteria, Actinobacteria and Bacteroidetes) also contributed to polyamine-related gene transcription.
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Establishment, characterization, and successful adaptive therapy against human tumors of NKG cell, a new human NK cell line.
Cell Transplant
PUBLISHED: 06-07-2011
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Natural killer (NK) cells play important roles in adoptive cellular immunotherapy against certain human cancers. This study aims to establish a new human NK cell line and to study its role for adoptive cancer immunotherapy. Peripheral blood samples were collected from 54 patients to establish the NK cell line. A new human NK cell line, termed as NKG, was established from a Chinese male patient with rapidly progressive non-Hodgkins lymphoma. NKG cells showed LGL morphology and were phenotypically identified as CD56(bright) NK cell with CD16(-), CD27(-), CD3(-), ??TCR(-), ??TCR(-), CD4(-), CD8(-), CD19(-), CD161(-), CD45(+), CXCR4(+), CCR7(+), CXCR1(-), and CX3CR1(-). NKG cells showed high expression of adhesive molecules (CD2, CD58, CD11a, CD54, CD11b, CD11c), an array of activating receptors (NKp30, NKp44, NKp46, NKG2D, NKG2C), and cytolysis-related receptors and molecules (TRAIL, FasL, granzyme B, perforin, IFN-?). The cytotoxicity of NKG cells against tumor cells was higher than that of the established NK cell lines NK-92, NKL, and YT. NKG cell cytotoxicity depended on the presence of NKG2D and NKp30. When irradiated with 8 Gy, NKG cells were still with high cytotoxicity and activity in vitro and with safety in vivo, but without proliferation. Further, the irradiated NKG cells exhibited strong cytotoxicity against human primary ovarian cancer cells in vitro, and against human ovarian cancer in a mouse xenograft model. The adoptive transfer of NKG cells significantly inhibited the ovarian tumor growth, decreased the mortality rate and prolonged the survival, even in cases of advanced diseases. A number of NKG cells were detected in the ovarian tumor tissues during cell therapy. In use of the new human NK cell line, NKG would a promising cellular candidate for adoptive immunotherapy of human cancer.
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Salmonella detoxifying enzymes are sufficient to cope with the host oxidative burst.
Mol. Microbiol.
PUBLISHED: 03-21-2011
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The oxidative burst produced by the NADPH oxidase (Phox) is an essential weapon used by host cells to eradicate engulfed pathogens. In Salmonella typhimurium, oxidative stress resistance has been previously proposed to be mediated by the pathogenicity island 2 type III secretion system (T3SS-2), periplasmic superoxide dismutases and cytoplasmic catalases/peroxidases. Here, we fused an OxyR-dependent promoter to the gfp to build the ahpC-gfp transcriptional fusion. This reporter was used to monitor hydrogen peroxide levels as sensed by Salmonella during the course of an infection. We showed that the expression of this fusion was under the exclusive control of reactive oxygen species produced by the host. The ahpC-gfp expression was noticeably modified in the absence of bacterial periplasmic superoxide dismutases or cytoplasmic catalases/peroxidases. Surprisingly, inactivation of the T3SS-2 had no effect on the ahpC-gfp expression. All together, these results led to a model in which Salmonella resistance relies on its arsenal of detoxifying enzymes to cope with Phox-mediated oxidative stress.
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Identification of compatibility between ooplasmic factor and sperm gene in the intersubspecific crosses involving DDK and PWK mice strains.
J Genet Genomics
PUBLISHED: 01-17-2011
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The DDK strain (Mus musculus domesticus) of inbred mouse has a unique peculiarity known as DDK syndrome. The DDK females are mostly infertile when crossed with males of other inbred strains, while DDK males exhibit normal fertility in the reciprocal crosses, as intrastrain matings. This DDK syndrome has been demonstrated to be caused by an incompatibility system between DDK ooplasmic factor and the sperm gene of other strains owing to the ovum mutant (Om) locus on mouse Chromosome 11. Recently, it was reported that DDK females are fully fertile when crossed to males of MOM (M. m. molossinus) and CASP (M. m. castaneus) strains, indicating that no incompatibilities exist between DDK ooplasmic factor and sperm gene of MOM or CASP males. In the present study, DDK females were found to be also fully fertile when crossed to the males of PWK wild-derived inbred strain (originated from Czech Republic wild mice, M. m. musculus). The crosses of DDK females×F(1) (DDK?×PWK?) males also resulted in normal fertility. Furthermore, the transmission ratios of Om alleles from these F(1) males to their backcross N(2) offspring are 50%:50% as genotyped by microsatellite markers closely linked to Om locus. Moreover, it was demonstrated that PWK females are also fully fertile when crossed to DDK males. All above results indicated that no incompatibility exists between ooplasmic factor and sperm gene in the intersubspecific crosses with DDK and PWK strains. PWK strain would also be useful for further investigations on the DDK syndrome, and DDK strain can be used more widely for various studies in the mouse.
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[Biomechanical study on effect of polymethylmethacrylate augmentation on cervical stability after anterior cervical interbody fusion].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 11-05-2010
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To evaluate the effect of polymethylmethacrylate (PMMA) augmentation on cervical stability after anterior cervical interbody fusion (ACIF) before and after fatigue.
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The virulence protein SopD2 regulates membrane dynamics of Salmonella-containing vacuoles.
PLoS Pathog.
PUBLISHED: 06-16-2010
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Salmonella enterica serovar Typhimurium is a Gram-negative bacterial pathogen causing gastroenteritis in humans and a systemic typhoid-like illness in mice. The capacity of Salmonella to cause diseases relies on the establishment of its intracellular replication niche, a membrane-bound compartment named the Salmonella-containing vacuole (SCV). This requires the translocation of bacterial effector proteins into the host cell by type three secretion systems. Among these effectors, SifA is required for the SCV stability, the formation of Salmonella-induced filaments (SIFs) and plays an important role in the virulence of Salmonella. Here we show that the effector SopD2 is responsible for the SCV instability that triggers the cytoplasmic release of a sifA(-) mutant. Deletion of sopD2 also rescued intra-macrophagic replication and increased virulence of sifA(-) mutants in mice. Membrane tubular structures that extend from the SCV are the hallmark of Salmonella-infected cells. Until now, these unique structures have not been observed in the absence of SifA. The deletion of sopD2 in a sifA(-) mutant strain re-established membrane trafficking from the SCV and led to the formation of new membrane tubular structures, the formation of which is dependent on other Salmonella effector(s). Taken together, our data demonstrate that SopD2 inhibits the vesicular transport and the formation of tubules that extend outward from the SCV and thereby contributes to the sifA(-) associated phenotypes. These results also highlight the antagonistic roles played by SopD2 and SifA in the membrane dynamics of the vacuole, and the complex actions of SopD2, SifA, PipB2 and other unidentified effector(s) in the biogenesis and maintenance of the Salmonella replicative niche.
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Biomechanical evaluation of an atlantoaxial lateral mass fusion cage with C1-C2 pedicle fixation.
Spine
PUBLISHED: 05-28-2010
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A biomechanical testing protocol was used to evaluate atlantoaxial fixation techniques in a human cadaveric model.
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[Biomechanical evaluation of TiNi shape-memory sawtooth-arm embracing plate and its effect on fracture healing].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 03-02-2010
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To investigate the detailed biomechanics of TiNi shape-memory sawtooth-arm embracing plate (TiNi SMA) by comparing with limited-contact dynamic compression plate (LC-DCP) and static interlocking intramedullary nail (SIiN), so as to provide theoretical evidence for clinical application.
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Laparoscopic extraperitoneal uterine suspension to anterior abdominal wall bilaterally using synthetic mesh to treat uterovaginal prolapse.
J Minim Invasive Gynecol
PUBLISHED: 01-16-2010
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Between August 2007 and May 2009, 28 patients with uterovaginal prolapse, stage 2 or greater, and who desired uterine preservation, underwent laparoscopic extraperitoneal uterine suspension to the anterior abdominal wall bilaterally using mesh. The primary outcome was recurrence, which was evaluated using point C. Secondary outcomes were effects on quality of life (Pelvic Floor Distress Inventory [PFDI-20] and Pelvic Floor Impact Questionnaire [PFIQ-7]) and sexual symptom (Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire [PISQ-12]) scores, operative time, blood loss, duration of hospitalization, and adverse events. After surgery, there was significant improvement in all pelvic organ prolapse quantification (POP-Q) measurements. The POP-Q score for point C was significantly farther from the hymen at 6-months and 1-year follow-up compared with the preoperative value (-7.8 and -8.0 vs 2.6, respectively; p < .001). The objective cure rates at 6 months and 1 year were 96.4% and 94.1%, respectively. There were no major intraoperative or postoperative complications. However, all patients reported postoperative dragging pain at the points of puncture ports where the mesh was fixed to the abdominal wall. The mean visual analog scale decreased from a mean (SD) 3-day score of 2.61 (1.26) to 0 at 1 month follow-up. Baseline PISQ-12 score changed significantly compared with the value at 6 months after operation (28.4 [2.7] vs 29.3 [2.9]; p < .001). The PFDI-20 and PFIQ-7 scores at 6 and 12 months after surgery improved significantly compared with the baseline scores (p < .001). The subjective success rates at 6 months and 1 year were 96.4% and 94.1%. respectively. Laparoscopic extraperitoneal uterine suspension to the anterior abdominal wall using mesh is a simple, safe, and effective procedure for treating uterovaginal prolapse. However, further studies of the long-term efficiency and reliability of this technique are needed to evaluate its value.
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REDD1 is a major target of testosterone action in preventing dexamethasone-induced muscle loss.
Endocrinology
PUBLISHED: 12-23-2009
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Glucocorticoids are a well-recognized and common cause of muscle atrophy that can be prevented by testosterone. However, the molecular mechanisms underlying such protection have not been described. Thus, the global effects of testosterone on dexamethasone-induced changes in gene expression were evaluated in rat gastrocnemius muscle using DNA microarrays. Gene expression was analyzed after 7-d administration of dexamethasone, dexamethasone plus testosterone, or vehicle. Dexamethasone changed expression of 876 probe sets by at least 2-fold. Among these, 474 probe sets were changed by at least 2-fold in the opposite direction in the dexamethasone plus testosterone group (genes in opposition). Major biological themes represented by genes in opposition included IGF-I signaling, myogenesis and muscle development, and cell cycle progression. Testosterone completely prevented the 22-fold increase in expression of the mammalian target of rapamycin (mTOR) inhibitor regulated in development and DNA damage responses 1 (REDD1), and attenuated dexamethasone induced increased expression of eIF4E binding protein 1, Forkhead box O1, and the p85 regulatory subunit of the IGF-I receptor but prevented decreased expression of IRS-1. Testosterone attenuated increases in REDD1 protein in skeletal muscle and L6 myoblasts and prevented dephosphorylation of p70S6 kinase at the mTOR-dependent site Thr389 in L6 myoblast cells. Effects of testosterone on REDD1 mRNA levels occurred within 1 h, required the androgen receptor, were blocked by bicalutamide, and were due to inhibition of transcriptional activation of REDD1 by dexamethasone. These data suggest that testosterone blocks dexamethasone-induced changes in expression of REDD1 and other genes that collectively would otherwise down-regulate mTOR activity and hence also down-regulate protein synthesis.
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Biomechanical assessment of bilateral C1 laminar hook and C1-2 transarticular screws and bone graft for atlantoaxial instability.
J Spinal Disord Tech
PUBLISHED: 12-04-2009
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STUDYDESIGN: In vitro biomechanical test was conducted to compare the stability of 5 different atlantoaxial posterior fusion techniques.
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Caldanaerovirga acetigignens gen. nov., sp. nov., an anaerobic xylanolytic, alkalithermophilic bacterium isolated from Trego Hot Spring, Nevada, USA.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 07-22-2009
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An anaerobic thermophilic bacterium, designated strain JW/SA-NV4(T), was isolated from a xylan-supplemented enrichment culture from Trego hot spring located within the Black Rock Desert (NV, USA). Cells were generally straight or slightly bent rod-shaped, 0.4-0.8 microm in width and 3-6 microm in length during exponential growth. Cells from stationary phase were variable in size and shape, showing curved or bent morphology. Motility was not seen and flagella were not observed in electron micrographs. Sporulation was not observed. Strain JW/SA-NV4(T) stained Gram-negative but is phylogenetically Gram-type positive. Growth occurred at pH(25 degrees C) 6.8-8.8, with optimum growth at pH 8.4; no growth occurred at pH 9.0 or above or at 6.5 or below. With glucose or xylose as the carbon source, strain JW/SA-NV4(T) grew at 44-74 degrees C; no growth occurred at 76 degrees C or above or at 42 degrees C or below. However, the optimum temperature was 62 and 66 degrees C when grown on glucose and xylose, respectively. The shortest doubling time observed with glucose was approximately 4 h, and with xylose approximately 3.4 h. Strain JW/SA-NV4(T) tolerated an atmosphere containing up to 0.1 % O(2); no growth occurred at a gas atmosphere of 0.2 % O(2). Chemo-organotrophic growth occurred with xylose, glucose, mannose, xylan, pyruvate, fructose, ribose, Casamino acids, mannitol, tryptone, peptone, cellobiose and yeast extract. When grown in mineral media containing 1 g yeast extract l(-1) as an electron donor, thiosulfate and sulfur were reduced to sulfide. The G+C content of the DNA was 38.6 mol% (HPLC). 16S rRNA gene sequence analysis placed strain JW/SA-NV4(T) within the order Thermoanaerobacterales and within the Thermoanaerobacterales Incertae Sedis Family III, specifically between taxa classified within the genera Thermosediminibacter and Thermovenabulum. The closest phylogenetic neighbours were Thermosediminibacter oceani JW/IW-1228P(T) (94.2 % 16S rRNA gene sequence similarity) and Thermosediminibacter litoriperuensis JW/YJL-1230-7/2(T) (94.0 %) [Lee, Y.-J., Wagner, I. D., Brice, M. E., Kevbrin, V. V., Mills, G. L., Romanek, C. S. & Wiegel, J. (2005). Extremophiles 9, 375-383]. Based on physiological and genotypic characteristics, strain JW/SA-NV4(T) (=DSM 18802(T)=ATCC BAA-1454(T)) is proposed to represent the type strain of a novel species in a novel genus, Caldanaerovirga acetigignens gen. nov., sp. nov.
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Differential skeletal muscle gene expression after upper or lower motor neuron transection.
Pflugers Arch.
PUBLISHED: 01-27-2009
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Causes of disuse atrophy include loss of upper motor neurons, which occurs in spinal cord injury (SCI) or lower motor neurons (denervation). Whereas denervation quickly results in muscle fibrillations, SCI causes delayed onset of muscle spasticity. To compare the influence of denervation or SCI on muscle atrophy and atrophy-related gene expression, male rats had transection of either the spinal cord or sciatic nerve and were sacrificed 3, 7, or 14 days later. Rates of atrophy increased gradually over the first week after denervation and then were constant. In contrast, atrophy after SCI peaked at 1 week, then declined sharply. The greater atrophy after SCI compared to denervation was preceded by high levels of ubiquitin ligase genes, MAFbx and MuRF1, which then also markedly declined. After denervation, however, expression of these genes remained elevated at lower levels throughout the 2-week time course. Interestingly, expression of the muscle growth factor, IGF-1 was increased at 3 days after denervation when fibrillation also peaks compared to SCI. Expression of IGF-1R, GADD45, myogenin, and Runx1 were also initially increased after denervation or SCI, with later declines in expression levels which correlated less well with rates of atrophy. Thus, there were significant time-dependent differences in muscle atrophy and MAFbx, MuRF1, and IGF-1 expression following SCI or denervation which may result from distinct temporal patterns of spontaneous muscle contractile activity due to injury to upper versus lower motor neurons.
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Dependence of dexamethasone-induced Akt/FOXO1 signaling, upregulation of MAFbx, and protein catabolism upon the glucocorticoid receptor.
Biochem. Biophys. Res. Commun.
PUBLISHED: 01-23-2009
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The muscle ubiquitin ligases MAFbx and MuRF1 are upregulated in and promote muscle atrophy. Upregulation of MAFbx and MuRF1 by glucocorticoids has been linked to activation of FOXO1 and FOXO3A resulting from reduced Akt activity. We determined the requirements for the glucocorticoid receptor (GR) in these biological responses in C2C12 cells in which GR expression was knocked down by stable expression of an shRNA. Loss of GR prevented dexamethasone-induced increases in protein catabolism. Loss of GR, or inhibition of ligand binding to GR with RU486, prevented upregulation of MAFbx and MuRF1 by dexamethasone. Loss of GR also prevented dexamethasone-induced decreases in Akt phosphorylation, and increases in the fraction of FOXO1 that was unphosphorylated. The findings establish a requirement for the GR in activating molecular signals that promote muscle protein catabolism.
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Sema3F downregulates p53 expression leading to axonal growth cone collapse in primary hippocampal neurons.
Int J Clin Exp Pathol
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Hippocampal nerve growth is regulated by the coordinated action of numerous external stimuli, including positively acting neurotrophin-derived growth cues and restrictive semaphorin cues, however the underlying cellular mechanisms remain largely unclear. We examined the potential cellular mechanism of Semaphorin3F (Sema3F) in cultured primary hippocampal neurons. We show that Sema3F can down-regulate p53 expression in primary hippocampal neurons, thereby contributing to growth cone collapse. Sema3F suppressed p53-induced pathways, which we show to be required to maintain growth cone structure. Sema3F-induced growth cone collapse was partially reversed by overexpression of p53, which promoted growth cone extension. Inhibition of p53 function by inhibitor, siRNAs, induced axonal growth cone collapse, whereas p53 over-expression led to larger growth cones in cultured primary hippocampal neurons.These data reveal a novel mechanism by which Sema3F can induce hippocampal neuron growth cone collapse and provide evidence for an intracellular mechanism for cross talk between positive and negative axon growth cues.
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Cable-strengthened C2 pedicle screw fixation in the treatment of congenital C2-3 fusion, atlas occipitalization, and atlantoaxial dislocation.
Neurosurgery
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Atlas occipitalization and congenital C2-3 fusion often result in atlantoaxial dislocation (AAD) and superior odontoid migration that requires occipitocervical fixation. The widely used technique is posterior occiput-C2 fixation with pedicle screws. However, congenital C2-3 fusion cases tend to have thinner C2 pedicles that are inadequate for normal-sized pedicle screw fixation. With the presence of AAD, the strength of the fixation is further compromised as the C2 pedicle screws (C2PS) sustain considerable cephalic shearing force during the reduction procedure. Therefore, a novel technique has been developed to augment the C2 pedicle screw fixation with a strengthening cable.
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Load-bearing evaluation of spinal posterior column by measuring surface strain from lumbar pedicles. An in vitro study.
Acta Bioeng Biomech
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An understanding of the load transfer within spinal posterior column of lumbar spine is necessary to determine the influence of mechanical factors on potential mechanisms of the motion-sparing implant such as artificial intervertebral disc and the dynamic spine stabilization systems. In this study, a new method has been developed for evaluating the load bearing of spinal posterior column by the surface strain of spinal pedicle response to the loading of spinal segment. Six cadaveric lumbar spine segments were biomechanically evaluated between levels L1 and L5 in intact condition and the strain gauges were pasted to an inferior surface of L2 pedicles. Multidirectional flexibility testing used the Panjabi testing protocol; pure moments for the intact condition with overall spinal motion and unconstrained intact moments of ±8 Nm were used for flexion-extension and lateral bending testing. High correlation coefficient (0.967-0.998) indicated a good agreement between the load of spinal segment and the surface strain of pedicle in all loading directions. Principal compressive strain could be observed in flexion direction and tensile strain in extension direction, respectively. In conclusion, the new method seems to be effective for evaluating posterior spinal column loads using pedicles surface strain data collected during biomechanical testing of spine segments.
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MRI study of the position of the conus medullaris in patients with lumbar spinal stenosis.
Orthopedics
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Substantial data exist from cadaveric and magnetic resonance imaging studies regarding the position of the conus medullaris in normally developed adults. However, no large studies have documented the position of the conus medullaris in patients with diagnosed lumbar spinal stenosis. To goal of the current study was to determine the position of the conus medullaris within a living adult population with existing pathology of lumbar spinal stenosis. In a retrospective study, 234 patients (110 women and 124 men; mean age, 48.8 years) with diagnosed lumbar spinal stenosis had their T2-weighted, midline, sagittal, spin-echo magnetic resonance imaging studies compared to assess and confirm the position of the conus medullaris. A straight line perpendicular to the long axis of the spinal cord in the median sagittal sequence was subtended to the adjacent vertebra or disk space, and the position was defined in relation to the vertebra or disk space. The conus medullaris position was labeled in relation to the upper, middle, and lower segments of the adjacent vertebral body or the adjacent disk space and assigned numerical values from 1 to 12. The position of the conus medullaris in patients with lumbar spinal stenosis followed a normal distribution. The mean conus medullaris position was mainly within the lower third of the L1 vertebral body (ranged from the middle third of T12 to the upper third of L3). No significant differences existed between men and women with lumbar spinal stenosis. The conus medullaris position was found to be unaffected by the pathology of lumbar spinal stenosis.
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A hypomorphic mutation in the Gfi1 transcriptional repressor results in a novel form of neutropenia.
Eur. J. Immunol.
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Using N-ethyl-N-nitrosourea-induced mutagenesis, we established a mouse model with a novel form of neutropenia resulting from a point mutation in the transcriptional repressor Growth Factor Independence 1 (Gfi1). These mice, called Genista, had normal viability and no weight loss, in contrast to mice expressing null alleles of the Gfi1 gene. Furthermore, the Genista mutation had a very limited impact on lymphopoiesis or on T- and B-cell function. Within the bone marrow (BM), the Genista mutation resulted in a slight increase of monopoiesis and in a block of terminal granulopoiesis. This block occurred just after the metamyelocytic stage and resulted in the generation of small numbers of atypical CD11b(+) Ly-6G(int) neutrophils, the nuclear morphology of which resembled that of mature WT neutrophils. Unexpectedly, once released from the BM, these atypical neutrophils contributed to induce mild forms of autoantibody-induced arthritis and of immune complex-mediated lung alveolitis. They additionally failed to provide resistance to acute bacterial infection. Our study demonstrates that a hypomorphic mutation in the Gfi1 transcriptional repressor results in a novel form of neutropenia characterized by a split pattern of functional responses, reflecting the distinct thresholds required for eliciting neutrophil-mediated inflammatory and anti-infectious responses.
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Direct evidence of lipid rafts by in situ atomic force microscopy.
Small
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Lipid rafts are membrane microdomains enriched with cholesterol, glycosphingolipids, and proteins. Although they are broadly presumed to play a pivotal role in various cellular functions, there are still fierce debates about the composition, functions, and even existence of lipid rafts. Here high-resolution and time-lapse in situ atomic force microscopy is used to directly confirm the existence of lipid rafts in native erythrocyte membranes. The results indicate some important aspects of lipid rafts: most of the lipid rafts are in the size range of 100-300 nm and have irregular shape; the detergent-resistant membranes consist of cholesterol microdomains and are not likely the same as the lipid rafts; cholesterol contributes significantly to the formation and stability of the protein domains; and Band III is an important protein of lipid rafts in the inner leaflet of erythrocyte membranes, indicating that lipid rafts are exactly the functional domains in plasma membrane. This work provides direct evidence of the presence, size, and main constitutive protein of lipid rafts at a resolution of a few nanometers, which will pave the way for studying their structure and functions in detail.
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Ossification of the posterior longitudinal and yellow ligaments on the lumbar spine.
Orthopedics
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Ossification of the posterior longitudinal ligament and ossification of the yellow ligament are the main causes of spinal canal stenosis. This article describes a case of ossification of the posterior longitudinal and yellow ligaments on the lumbar spine. The patient presented with gradually worsening left lower-extremity ache and pain. The deep tendon reflex was hyperreflexia in the lower extremities. Disturbances existed in the blade and bowel. The ossified lesion of ossification of the posterior longitudinal ligament was observed at L5-S1, and plain lateral radiographs and computed tomography revealed ossification of the yellow ligament on L3, which occupied a large part of the spinal canal. Because of the findings on the preoperative radiographs, we performed posterior approach decompression and bone grafting and excisied the ossified lesion. Pedicle screws were inserted from L3 to S1. The patients symptoms disappeared postoperatively, and his Japanese Orthopaedic Association score was 25 two weeks postoperatively. No standard surgical procedure exists for the treatment of lumbar ossification of the posterior longitudinal ligament, but it is important to select a surgical procedure according to individual patient conditions. Many factors, such as local mechanic stress, tissue metabolism, high glucose, and genetics, contribute to the progression of ossification of the posterior longitudinal and yellow ligaments on the lumbar spine. However, the mechanism is unclear. Further study and long-term follow-up on lumbar ossification of the posterior longitudinal ligament is needed.
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Modified laparoscopic extraperitoneal uterine suspension to anterior abdominal wall: the easier way to treat uterine prolapse.
Int Urogynecol J
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To report the outcomes of modified laparoscopic extraperitoneal uterine suspension to anterior abdominal wall for uterine prolapse using mesh.
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