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Find video protocols related to scientific articles indexed in Pubmed.
Improving quality through performance-based financing in district hospitals in Rwanda between 2006 and 2010: A 5-year experience.
Trop Doct
PUBLISHED: 11-20-2014
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Since 2000 performance-based financing (PBF) made its way to sub-Saharan health systems in an attempt to improve service delivery. In Rwanda initial experiences in 2001 and 2002 led to a scaling up of the initiative to all health centres (HC) and district hospitals (DH). In 2008 PBF became national strategy.
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Meal frequency and timing in health and disease.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-19-2014
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Although major research efforts have focused on how specific components of foodstuffs affect health, relatively little is known about a more fundamental aspect of diet, the frequency and circadian timing of meals, and potential benefits of intermittent periods with no or very low energy intakes. The most common eating pattern in modern societies, three meals plus snacks every day, is abnormal from an evolutionary perspective. Emerging findings from studies of animal models and human subjects suggest that intermittent energy restriction periods of as little as 16 h can improve health indicators and counteract disease processes. The mechanisms involve a metabolic shift to fat metabolism and ketone production, and stimulation of adaptive cellular stress responses that prevent and repair molecular damage. As data on the optimal frequency and timing of meals crystalizes, it will be critical to develop strategies to incorporate those eating patterns into health care policy and practice, and the lifestyles of the population.
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?-adrenergic antagonists influence abdominal aorta contractility by mechanisms not involving ?-adrenergic receptors.
Folia Biol. (Krakow)
PUBLISHED: 11-19-2014
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?-adrenergic receptors (?-AR) are widely distributed in the cardiovascular system, where they considerably contribute to the control of its functions. ?-blockers are commonly used in the treatment of disorders of the circulatory system. They act primarily by inhibiting cardiac ?-receptors. However, there are also reports of pleiotropic action of ?-blockers as well as of new compounds created to study ?3 adrenergic receptors. The study aimed to investigate additional mechanisms of action of ?-AR inhibitors in the rabbit abdominal aorta with emphasis on their action on ?-adrenergic receptors and calcium influx. Responses to propranolol, betaxolol, metoprolol and SR59230A were evaluated in phenylephrine and PGF(2alpha) precontracted aortic rings. The effect of propranolol on the phenylephrine concentration-contraction curve was examined. Propranolol (? 10 ?M) and SR59230A (? 0.1 ?M) induced relaxations in phenylephrine-precontracted rings, while betaxolol and metoprolol had little effect. The ?-AR inhibitors produced further contraction of tissues preincubated with PGF(2alpha), excluding SR59230A, which after initial contraction, elicited marked relaxation at a concentration above 1 ?M. 100 ?M of propranolol caused a significant rightward shift of the concentration-contraction curve to phenylephrine with no reduction in the maximum response. Incubation of aortic rings in phentolamine reduced the maximal contraction to propranolol; verapamil pretreatment by contrast enhanced contractile response. In conclusion, SR59230A and propranolol most probably act as ?1-AR competitive antagonists in the presence of phenylephrine in rabbit abdominal aortic rings. After ?-ARs blockade, propranolol exerts a weak relaxing activity connected with Ca2+ channel inactivation. SR59230A at a high concentration acts on the rabbit aorta by an additional mechanism needing further investigation.
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Laser interaction with materials: introduction.
Appl Opt
PUBLISHED: 11-18-2014
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Laser-materials interaction is the fascinating nexus where laser physics, optical physics, and materials science intersect. Applications include microdeposition via laser-induced forward transfer of thin films, clean materials processing with femtosecond beams, creating color filters with nanoparticles, generating very high density storage sites on subpicosecond time scales, structuring solar cell surfaces for higher efficiency, making nanostructures that would be impossible by other means, and creating in-volume waveguiding structures using femtosecond laser filaments.
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Sexual Functioning in Women after Surgical Treatment for Endometrial Cancer: A Prospective Controlled Study.
J Sex Med
PUBLISHED: 11-18-2014
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Endometrial cancer (EC) can affect sexual functioning based on anatomical, physiological, psychological, and relational mechanisms.
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Preclinical evidence for the therapeutic potential of CD38-targeted immuno-chemotherapy in multiple myeloma patients refractory to lenalidomide and bortezomib.
Clin. Cancer Res.
PUBLISHED: 11-16-2014
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Purpose: Novel therapeutic agents have significantly improved the survival of multiple myeloma (MM) patients. Nonetheless, the prognosis of MM patients who become refractory to the novel agents lenalidomide (LEN) and bortezomib (BOR) is very poor, indicating the urgent need for new therapeutic options for these patients. The human CD38 monoclonal antibody daratumumab (DARA) is being evaluated as a novel therapy for MM. Prompted with the encouraging results of ongoing clinical phase I/II trials, we now addressed the potential value of DARA alone or in combination with LEN or BOR for the treatment of LEN- and BOR-refractory patients. Experimental Design: In ex vivo assays, mainly evaluating antibody-dependent cellular cytotoxicity (ADCC), and in an in vivo xenograft mouse model we evaluated DARA alone or in combination with LEN or BOR as a potential therapy for LEN- and BOR-refractory MM patients. Results: DARA induced significant lysis of LEN/BOR-resistant MM cell lines and of primary MM cells in the bone marrow mononuclear cells derived from LEN- and/or BOR-refractory patients. In these assays LEN but not BOR, synergistically enhanced DARA-mediated MM lysis through activation of natural killer (NK) cells. Finally, in an in vivo xenograft model, only the combination of DARA with LEN effectively reduced the tumorigenic growth of primary MM cells from a LEN- and BOR-refractory patient. Conclusions: Our results provide the first preclinical evidence for the benefit of DARA plus LEN combination for LEN- and BOR-refractory patients.
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Spot them in the spot: analysis of abused substances using dried blood spots.
Bioanalysis
PUBLISHED: 11-11-2014
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Dried blood spot (DBS) sampling and DBS analysis have increasingly received attention during recent years. Furthermore, a substantial number of DBS methods has recently become available in clinical, forensic and occupational toxicology. In this review, we provide an overview of the different DBS-based methods that have been developed for detecting (markers of) abused substances. These include both legal and illegal drugs belonging to different categories, including cannabinoids, cocaine and metabolites, opioids, benzodiazepines and Z-drugs, amphetamines and analogs, gamma-hydroxybutyric acid, ketamine and novel psychoactive substances such as cathinones. Markers of ethanol consumption and tobacco use are also covered in this review. Since the majority of published methods has shown promising results overall, an interesting role for DBS analysis in diverse toxicological applications can be envisaged. For the distinct applications, we discuss the specific potential and benefits of DBS, the associated limitations and challenges, as well as recent developments and future perspectives.
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Astaxanthin diferulate as a bifunctional antioxidant.
Free Radic. Res.
PUBLISHED: 11-04-2014
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Abstract Astaxanthin when esterified with ferulic acid is better singlet-oxygen quencher with k2 = (1.58 ± 0.1) 10(10) L mol(-1)s(-1) in ethanol at 25°C compared to astaxanthin with k2 = (1.12 ± 0.01) 10(9) L mol(-1)s(-1). The ferulate moiety is in the astaxanthin diester a better radical scavenger than free ferulic acid as seen from the rate constant of scavenging of 1-hydroxyethyl radicals in ethanol at 25°C with a second-order rate constant of (1.68 ± 0.1) 10(8) L mol(-1)s(-1) compared to (1.60 ± 0.03) 10(7) L mol(-1)s(-1) for the astaxanthin:ferulic acid mixture, 1:2 equivalents. The mutual enhancement of antioxidant activity for the newly synthetized astaxanthin diferulate becoming a bifunctional antioxidant is rationalized according to a two-dimensional classification plot for electron donation and electron acceptance capability.
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Paleoindian settlement of the high-altitude Peruvian Andes.
Science
PUBLISHED: 10-25-2014
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Study of human adaptation to extreme environments is important for understanding our cultural and genetic capacity for survival. The Pucuncho Basin in the southern Peruvian Andes contains the highest-altitude Pleistocene archaeological sites yet identified in the world, about 900 meters above confidently dated contemporary sites. The Pucuncho workshop site [4355 meters above sea level (masl)] includes two fishtail projectile points, which date to about 12.8 to 11.5 thousand years ago (ka). Cuncaicha rock shelter (4480 masl) has a robust, well-preserved, and well-dated occupation sequence spanning the past 12.4 thousand years (ky), with 21 dates older than 11.5 ka. Our results demonstrate that despite cold temperatures and low-oxygen conditions, hunter-gatherers colonized extreme high-altitude Andean environments in the Terminal Pleistocene, within about 2 ky of the initial entry of humans to South America.
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Healing of rabbit calvarial critical-sized defects using autogenous bone grafts and fibrin glue.
Childs Nerv Syst
PUBLISHED: 09-18-2014
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This study aimed to evaluate ossification of cranial bone defects comparing the healing of a single piece of autogenous calvarial bone representing a bone flap as in cranioplasty compared to particulated bone slurry with and without fibrin glue to represent bone collected during cranioplasty. These defect-filling materials were then compared to empty control cranial defects.
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Potent Immune Responses in Rhesus Macaques Induced by Nonviral Delivery of a Self-amplifying RNA Vaccine Expressing HIV Type 1 Envelope With a Cationic Nanoemulsion.
J. Infect. Dis.
PUBLISHED: 09-18-2014
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Self-amplifying messenger RNA (mRNA) of positive-strand RNA viruses are effective vectors for in situ expression of vaccine antigens and have potential as a new vaccine technology platform well suited for global health applications. The SAM vaccine platform is based on a synthetic, self-amplifying mRNA delivered by a nonviral delivery system. The safety and immunogenicity of an HIV SAM vaccine encoding a clade C envelope glycoprotein formulated with a cationic nanoemulsion (CNE) delivery system was evaluated in rhesus macaques. The HIV SAM vaccine induced potent cellular immune responses that were greater in magnitude than those induced by self-amplifying mRNA packaged in a viral replicon particle (VRP) or by a recombinant HIV envelope protein formulated with MF59 adjuvant, anti-envelope binding (including anti-V1V2), and neutralizing antibody responses that exceeded those induced by the VRP vaccine. These studies provide the first evidence in nonhuman primates that HIV vaccination with a relatively low dose (50 µg) of formulated self-amplifying mRNA is safe and immunogenic.
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Long-term sexual functioning in women after surgical treatment of cervical cancer stages IA to IB: a prospective controlled study.
Int. J. Gynecol. Cancer
PUBLISHED: 09-03-2014
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Women with cervical cancer (CC) may be faced with changes in sexual functioning resulting from the cancer itself and/or its surgical treatment. The aims of this study were to prospectively investigate sexual adjustment of CC patients during a follow-up period of 2 years after radical hysterectomy without adjuvant treatment and to compare the results with women who underwent a hysterectomy for a benign gynecological condition and with healthy control women.
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45,X/46,XY mosaicism: report on 14 patients from a Brazilian hospital. A retrospective study.
Sao Paulo Med J
PUBLISHED: 09-02-2014
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45,X/46,XY mosaicism, or mixed gonadal dysgenesis, is considered to be a rare disorder of sex development. The aim of our study was to investigate the clinical and cytogenetic characteristics of patients with this mosaicism.
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45,X/46,XY mosaicism: report on 14 patients from a Brazilian hospital. A retrospective study.
Sao Paulo Med J
PUBLISHED: 09-02-2014
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45,X/46,XY mosaicism, or mixed gonadal dysgenesis, is considered to be a rare disorder of sex development. The aim of our study was to investigate the clinical and cytogenetic characteristics of patients with this mosaicism.
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Potassium-based algorithm allows correction for the hematocrit bias in quantitative analysis of caffeine and its major metabolite in dried blood spots.
Anal Bioanal Chem
PUBLISHED: 08-29-2014
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Although dried blood spot (DBS) sampling is increasingly receiving interest as a potential alternative to traditional blood sampling, the impact of hematocrit (Hct) on DBS results is limiting its final breakthrough in routine bioanalysis. To predict the Hct of a given DBS, potassium (K(+)) proved to be a reliable marker. The aim of this study was to evaluate whether application of an algorithm, based upon predicted Hct or K(+) concentrations as such, allowed correction for the Hct bias. Using validated LC-MS/MS methods, caffeine, chosen as a model compound, was determined in whole blood and corresponding DBS samples with a broad Hct range (0.18-0.47). A reference subset (n?=?50) was used to generate an algorithm based on K(+) concentrations in DBS. Application of the developed algorithm on an independent test set (n?=?50) alleviated the assay bias, especially at lower Hct values. Before correction, differences between DBS and whole blood concentrations ranged from -29.1 to 21.1%. The mean difference, as obtained by Bland-Altman comparison, was -6.6% (95% confidence interval (CI), -9.7 to -3.4%). After application of the algorithm, differences between corrected and whole blood concentrations lay between -19.9 and 13.9% with a mean difference of -2.1% (95% CI, -4.5 to 0.3%). The same algorithm was applied to a separate compound, paraxanthine, which was determined in 103 samples (Hct range, 0.17-0.47), yielding similar results. In conclusion, a K(+)-based algorithm allows correction for the Hct bias in the quantitative analysis of caffeine and its metabolite paraxanthine.
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Variants in CUL4B are Associated with Cerebral Malformations.
Hum. Mutat.
PUBLISHED: 08-21-2014
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Variants in CUL4B are a known cause of syndromic X-linked intellectual disability. Here, we describe an additional 25 patients from eleven families with variants in CUL4B. We identified nine different novel variants in these families and confirmed the pathogenicity of all non-truncating variants. Neuroimaging data, available for 15 patients, showed the presence of cerebral malformations in ten patients. The cerebral anomalies comprised malformations of cortical development, ventriculomegaly and diminished white matter volume. The phenotypic heterogeneity of the cerebral malformations might result from the involvement of CUL-4B in various cellular pathways essential for normal brain development. Accordingly, we show that CUL-4B interacts with WDR62, a protein in which variants were previously identified in patients with microcephaly and a wide range of MCD. This interaction might contribute to the development of cerebral malformations in patients with variants in CUL4B. This article is protected by copyright. All rights reserved.
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Factors Contributing to the Risk of HIV Infection in Rural School-Going Adolescents.
Int J Environ Res Public Health
PUBLISHED: 08-08-2014
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The objective of this study was to determine the factors that increase the risk of HIV infection in rural school-going adolescents and young adults. This was a cross-sectional study of 430 secondary school students (47.4% boys and 52.6% girls) from two rural schools in South Africa. Data were collected with a self-administered questionnaire on demographic information, sources of HIV/AIDS information, HIV knowledge, sexual behaviors, communication and negotiation skills, self-efficacy to refuse sex, peer influence and time perspective. Out of 113 (27.2%) participants who reported being sexually active, about 48% reported having had sex before the age of 15 and 42.2% reported penetrative sex with more than one partner in their lifetime. Only 44.8% of them reported consistent and regular use of condoms for every sexual encounter. Peer influence (OR = 3.01 (95% CI = 1.97-4.60)), gender difference (OR = 6.60 (95% CI = 1.62-26.84)) and lack of HIV information (OR = 1.22 (95% CI = 1.03-1.44)) influenced the sexual risk behaviors of the adolescents. Greater numbers of school-going adolescents in rural areas are sexually active. Peer influence, especially in boys, is a factor that increases the preponderance of risky sexual behaviors in adolescents. Positively, adolescents with high knowledge of HIV infection are more likely to use condoms for every sexual encounter. There is a need to strengthen comprehensive sexual health education and youth-friendly HIV prevention strategies to promote abstinence and safe sexual behaviors, especially among boys.
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CYP1A2 phenotyping in dried blood spots and microvolumes of whole blood and plasma.
Bioanalysis
PUBLISHED: 08-07-2014
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Background: Phenotyping, using caffeine as probe substrate, is a proper method to assess CYP1A2 activity. We evaluated the utility of dried blood spots (DBS) for CYP1A2 phenotyping. Results: LC-MS/MS methods were developed and validated for quantitation of caffeine and its metabolite paraxanthine in DBS, whole blood and plasma. All parameters met the pre-established criteria. While recovery, matrix effects and precision were unaffected by hematocrit (Hct), there was a Hct effect on accuracy, although for the evaluated Hct interval (0.36-0.50) it remained within acceptable limits. The phenotyping methods were successfully applied in healthy volunteers. Conclusion: Excellent method performance and highly comparable phenotyping indices in DBS, whole blood and plasma, combined with the benefits of DBS sampling, illustrate the suitability of DBS-based CYP1A2 phenotyping.
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Interdependency of selected metabolic variables in an animal model of metabolic syndrome.
Exp Ther Med
PUBLISHED: 08-06-2014
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In the present study, the correlation between the percentage of glycated hemoglobin, taken as representative of changes in glucose homeostasis, and selected variables was investigated. Rats were treated for 8 weeks with diets containing 64% starch and 5% sunflower oil or containing 64% D-fructose mixed with: 5% sunflower oil; 3.4% sunflower oil and 1.6% salmon oil; or 3.4% sunflower oil and 1.6% safflower oil. Positive correlations were found between glycated hemoglobin and plasma albumin, urea, creatinine, phospholipids, triglycerides and total cholesterol, liver cholesterol, triglyceride and phospholipid content, and the plasma, liver, heart, kidney, soleus muscle and visceral adipose tissue content of thiobarbituric acid reactive substances, carbonyl derivatives and hydroperoxides. Inversely, negative correlations were observed between glycated hemoglobin and plasma calcium, iron and HDL-cholesterol concentrations, liver, heart, kidney, soleus muscle and visceral adipose tissue superoxide dismutase and catalase activity; as well as plasma, liver, heart, kidney, soleus muscle and visceral adipose tissue nitric oxide content. Only the liver glucokinase activity and liver, heart, kidney, soleus muscle and visceral adipose tissue glutathione reductase activity failed to display a significant correlation with glycated hemoglobin. These findings confirm the hypothesis that there is a close association between glucose homeostasis and other variables when considering the effects of long-chain polyunsaturated ?3 and ?6 fatty acids in rats with fructose-induced metabolic syndrome.
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Exercise Preconditioning Protects against Spinal Cord Injury in Rats by Upregulating Neuronal and Astroglial Heat Shock Protein 72.
Int J Mol Sci
PUBLISHED: 08-04-2014
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The heat shock protein 72 (HSP 72) is a universal marker of stress protein whose expression can be induced by physical exercise. Here we report that, in a localized model of spinal cord injury (SCI), exercised rats (given pre-SCI exercise) had significantly higher levels of neuronal and astroglial HSP 72, a lower functional deficit, fewer spinal cord contusions, and fewer apoptotic cells than did non-exercised rats. pSUPER plasmid expressing HSP 72 small interfering RNA (SiRNA-HSP 72) was injected into the injured spinal cords. In addition to reducing neuronal and astroglial HSP 72, the (SiRNA-HSP 72) significantly attenuated the beneficial effects of exercise preconditioning in reducing functional deficits as well as spinal cord contusion and apoptosis. Because exercise preconditioning induces increased neuronal and astroglial levels of HSP 72 in the gray matter of normal spinal cord tissue, exercise preconditioning promoted functional recovery in rats after SCI by upregulating neuronal and astroglial HSP 72 in the gray matter of the injured spinal cord. We reveal an important function of neuronal and astroglial HSP 72 in protecting neuronal and astroglial apoptosis in the injured spinal cord. We conclude that HSP 72-mediated exercise preconditioning is a promising strategy for facilitating functional recovery from SCI.
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The use of dried blood spots for quantification of 15 antipsychotics and 7 metabolites with ultra-high performance liquid chromatography - tandem mass spectrometry.
Drug Test Anal
PUBLISHED: 07-31-2014
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Therapeutic drug monitoring of antipsychotics is important in optimizing individual therapy. In psychiatric populations, classical venous blood sampling is experienced as frightening. Interest in alternative techniques, like dried blood spots (DBS), has consequently increased. A fast and easy to perform DBS method for quantification of 16 antipsychotics (amisulpride, aripiprazole, asenapine, bromperidol, clozapine, haloperidol, iloperidone, levosulpiride, lurasidone, olanzapine, paliperidone, pipamperone, quetiapine, risperidone, sertindole and zuclopenthixol) and 8 metabolites was developed. DBS were prepared using 25??L of whole blood and extraction of complete spots was performed using methanol: methyl-t-butyl-ether (4:1). After evaporation, the extract was reconstituted in the mobile phase and 10??L were injected on an ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Separation using a C18 column and gradient elution with a flow rate of 0.5?mL/min resulted in a 6-min run-time. Ionization was performed in positive mode and a dynamic MRM method was applied. Median recovery was 66.4 % (range 28.7-84.5%). Accuracy was within the acceptance criteria, except for pipamperone (LLOQ and low concentration) and lurasidone (low concentration). Imprecision was only aberrant for lurasidone at low and medium concentration. All compounds were stable during 1?month at room temperature, 4?°C and -18?°C. Lurasidone was unstable when the extract was stored for 12?h on the autosampler. Absolute matrix effects (ME) (median 66.1%) were compensated by the use of deuterated IS (median 98.8%). The DBS method was successfully applied on 25-?L capillary DBS from patients and proved to be a reliable alternative for quantification of all antipsychotics except for olanzapine and N-desmethylolanzapine. Copyright © 2014 John Wiley & Sons, Ltd.
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Dopaminergic System Dysfunction in Recreational Dexamphetamine Users.
Neuropsychopharmacology
PUBLISHED: 07-25-2014
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Dexamphetamine (dAMPH) is a stimulant drug that is widely used recreationally as well as for treatment of attention deficit hyperactivity disorder (ADHD). Although animal studies have shown neurotoxic effects of dAMPH on the dopaminergic system, little is known about such effects on the human brain. Here, we studied the dopaminergic system at multiple physiological levels in recreational dAMPH users and age, gender and IQ-matched dAMPH-naïve healthy controls. We assessed baseline D2/3 receptor availability, in addition to changes in DA release using single-photon emission computed tomography (SPECT) and DA functionality using pharmacological magnetic resonance imaging (phMRI) following a dAMPH challenge. Also, the subjective responses to the challenge were determined. dAMPH users displayed significantly lower striatal DA D2/3 receptor binding compared to healthy controls. In dAMPH users we further observed a blunted DA release and DA functionality to an acute dAMPH challenge, as well as a blunted subjective response. Finally, the lower D2/3 availability, the more pleasant the dAMPH administration was experienced by control subjects, but not by dAMPH users. Thus, in agreement with preclinical studies, we show that recreational use of dAMPH in human subjects is associated with dopaminergic system dysfunction. These findings warrant further (longitudinal) investigations, and call for caution when using this drug recreationally and for ADHD.Neuropsychopharmacology accepted article preview online, 14 November 2014. doi:10.1038/npp.2014.301.
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Enriching the hierarchical model of achievement motivation: Autonomous and controlling reasons underlying achievement goals.
Br J Educ Psychol
PUBLISHED: 07-16-2014
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The hierarchical model of achievement motivation presumes that achievement goals channel the achievement motives of need for achievement and fear of failure towards motivational outcomes. Yet, less is known whether autonomous and controlling reasons underlying the pursuit of achievement goals can serve as additional pathways between achievement motives and outcomes.
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Development of Wireless Oral-feeding Monitoring System for Preterm Infants.
IEEE J Biomed Health Inform
PUBLISHED: 07-12-2014
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Oral feeding disorder is common in preterm infants. It not only shows the adverse effect for growth and neurodevelopment in clinical but also becomes one of the important indicators of high risk group for neurodevelopment delay in preterm infants. Preterm infants must coordinate the motor patterns of sucking, swallowing, and respiration skillfully to avoid chocking, aspiration, oxygen desaturation, bradycardia or apnea episodes. However, up to now, the judgment and classification severity in preterm infants are mostly subjective and phasic evaluations. Directly monitoring the coordination of sucking-swallowing-breathing during oral feeding simultaneously is difficult for preterm infants. In this study, we proposed a wireless oral feeding monitoring system for preterm infants to quantitatively monitor sucking pressure via a designed sucking pressure sensing device, swallowing activity via a microphone to detect swallowing sound, and diaphragmatic breathing movement via surface electromyogram. Moreover, a sucking-swallowing-breathing detection algorithm is also proposed to evaluate the events of sucking-swallowing-breathing activities. Further verification of the accuracy and rationality of oral feeding parameters with clinical findings including sucking, swallowing, and breathing in term and preterm infants had proved the practicality and value of the proposed system.
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Two male adults with pathogenic AUTS2 variants, including a two-base pair deletion, further delineate the AUTS2 syndrome.
Eur. J. Hum. Genet.
PUBLISHED: 07-04-2014
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AUTS2 syndrome is characterized by low birth weight, feeding difficulties, intellectual disability, microcephaly and mild dysmorphic features. All affected individuals thus far were caused by chromosomal rearrangements, variants at the base pair level disrupting AUTS2 have not yet been described. Here we present the full clinical description of two affected men with intragenic AUTS2 variants (one two-base pair deletion in exon 7 and one deletion of exon 6). Both variants are de novo and are predicted to cause a frameshift of the full-length transcript but are unlikely to affect the shorter 3' transcript starting in exon 9. The similarities between the phenotypes of both men are striking and further support that AUTS2 syndrome is a single gene disorder.European Journal of Human Genetics advance online publication, 10 September 2014; doi:10.1038/ejhg.2014.173.
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Why dried blood spots are an ideal tool for CYP1A2 phenotyping.
Clin Pharmacokinet
PUBLISHED: 07-02-2014
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Dried blood spot (DBS) sampling has gained wide interest in bioanalysis during the last decade and has already been successfully applied in pharmacokinetic and phenotyping studies. However, all of the available phenotyping studies used small datasets and did not include a systematic evaluation of DBS-specific parameters. The latter is important since several of these factors still challenge the breakthrough of DBS in routine practice. In this study, caffeine and paraxanthine are determined in capillary DBS, venous DBS, whole blood and plasma for cytochrome P450 (CYP) 1A2 phenotyping. The aim of this study was to explore the usefulness of DBS as a tool for CYP1A2 phenotyping.
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Factors impacting the provision of antiretroviral therapy to people living with HIV: the view from Haiti.
Antivir. Ther. (Lond.)
PUBLISHED: 05-19-2014
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Haiti is the poorest country in the Western Hemisphere and has the highest number of people living with HIV in the Caribbean, the region most impacted by HIV outside of Africa. Despite continuous political, socioeconomic and natural catastrophes, Haiti has mounted a very successful response to the HIV epidemic. Prevention and treatment strategies implemented by the government in collaboration with non-governmental organizations have been instrumental in decreasing the national HIV prevalence from a high of 6.2% in 1993 to 2.2% in 2012. We describe the history and epidemiology of HIV in Haiti and the expansion of antiretroviral therapy (ART) over the past decade, with the achievement of universal access to ART for patients meeting the 2010 World Health Organization guidelines. We also describe effective models of care, successes and challenges of international funding, and current challenges in the provision of ART. We are optimistic that the goal of providing ART for all in need remains in reach.
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In vivo mapping of vascular inflammation using the translocator protein tracer 18F-FEDAA1106.
Mol Imaging
PUBLISHED: 05-15-2014
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Noninvasive imaging methods are required to monitor the inflammatory content of atherosclerotic plaques. FEDAA1106 (N-(5-fluoro-2-phenoxyphenyl)-N-(2-(2-fluoroethoxy)-5-methoxybenzyl) acetamide) is a selective ligand for TSPO-18kDa (also known as peripheral benzodiazepine receptor), which is expressed by activated macrophages. We compared 18F-FEDAA1106 and 2-deoxy-2-[18F]fluoro-d-glucose (18F-FDG, a marker of glucose metabolism) for positron emission tomographic (PET) imaging of vascular inflammation. This was tested using a murine model in which focal inflammation was induced in the carotid artery via placement of a constrictive cuff. Immunostaining revealed CD68-positive cells (macrophages) at a disturbed flow site located downstream from the cuff. Dynamic PET imaging using 18F-FEDAA1106 or 18F-FDG was registered to anatomic data generated by computed tomographic (CT)/CT angiography. Standardized uptake values were significantly increased at cuffed compared to contralateral arteries using either 18F-FEDAA1106 (p < .01) or FDG (p < .05). However, the 18F-FEDAA1106 signal was significantly higher at the inflamed disturbed flow region compared to the noninflamed uniform flow regions, whereas differences in FDG uptake were less distinct. We conclude that 18F-FEDAA1106 can be used in vivo for detection of vascular inflammation. Moreover, the signal pattern of 18F-FEDAA1106 corresponded with vascular inflammation more specifically than FDG uptake.
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Heterozygous germline mutations in A2ML1 are associated with a disorder clinically related to Noonan syndrome.
Eur. J. Hum. Genet.
PUBLISHED: 04-29-2014
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Noonan syndrome (NS) is a developmental disorder characterized by short stature, facial dysmorphisms and congenital heart defects. To date, all mutations known to cause NS are dominant, activating mutations in signal transducers of the RAS/mitogen-activated protein kinase (MAPK) pathway. In 25% of cases, however, the genetic cause of NS remains elusive, suggesting that factors other than those involved in the canonical RAS/MAPK pathway may also have a role. Here, we used family-based whole exome sequencing of a case-parent trio and identified a de novo mutation, p.(Arg802His), in A2ML1, which encodes the secreted protease inhibitor ?-2-macroglobulin (A2M)-like-1. Subsequent resequencing of A2ML1 in 155 cases with a clinical diagnosis of NS led to the identification of additional mutations in two families, p.(Arg802Leu) and p.(Arg592Leu). Functional characterization of these human A2ML1 mutations in zebrafish showed NS-like developmental defects, including a broad head, blunted face and cardiac malformations. Using the crystal structure of A2M, which is highly homologous to A2ML1, we identified the intramolecular interaction partner of p.Arg802. Mutation of this residue, p.Glu906, induced similar developmental defects in zebrafish, strengthening our conclusion that mutations in A2ML1 cause a disorder clinically related to NS. This is the first report of the involvement of an extracellular factor in a disorder clinically related to RASopathies, providing potential new leads for better understanding of the molecular basis of this family of developmental diseases.European Journal of Human Genetics advance online publication, 18 June 2014; doi:10.1038/ejhg.2014.115.
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Examining correlates of game-to-game variation in volleyball players' achievement goal pursuit and underlying autonomous and controlling reasons.
J Sport Exerc Psychol
PUBLISHED: 04-02-2014
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In the current study we aimed to examine the antecedents and outcomes associated with the variability in competitive volleyball players' (N = 67; Mage = 19.45; SD = 5.13) situational achievement goal pursuit and its underlying autonomous and controlling reasons. Players were followed during six consecutive games and data were analyzed through multilevel modeling. Players' dominant contextual goal pursuit reported at the onset of the study related to their situational (i.e., game-specific) goal pursuit. Further, variation in game-to-game mastery-approach goal pursuit, as compared with the pursuit of other achievement goals, related to variation in prosocial behavior. Finally, autonomous reasons underlying situational mastery-approach goal pursuit related positively to games-specific prosocial behavior, enjoyment, and performance satisfaction. The discussion emphasizes the necessity to study players' game-to-game motivational dynamics and the reasons underlying players' achievement goal pursuit.
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Experimental infection of rhesus macaques and common marmosets with a European strain of West Nile virus.
PLoS Negl Trop Dis
PUBLISHED: 04-01-2014
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West Nile virus (WNV) is a mosquito-borne flavivirus that infects humans and other mammals. In some cases WNV causes severe neurological disease. During recent years, outbreaks of WNV are increasing in worldwide distribution and novel genetic variants of the virus have been detected. Although a substantial amount of data exists on WNV infections in rodent models, little is known about early events during WNV infection in primates, including humans. To gain a deeper understanding of this process, we performed experimental infections of rhesus macaques and common marmosets with a virulent European WNV strain (WNV-Ita09) and monitored virological, hematological, and biochemical parameters. WNV-Ita09 productively infected both monkey species, with higher replication and wider tissue distribution in common marmosets compared to rhesus macaques. The animals in this study however, did not develop clinical signs of WNV disease, nor showed substantial deviations in clinical laboratory parameters. In both species, the virus induced a rapid CD56dimCD16bright natural killer response, followed by IgM and IgG antibody responses. The results of this study show that healthy rhesus macaques and common marmosets are promising animal models to study WNV-Ita09 infection. Both models may be particularly of use to evaluate potential vaccine candidates or to investigate WNV pathogenesis.
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Folate Profiling in Potato (Solanum tuberosum) Tubers by Ultrahigh-Performance Liquid Chromatography-Tandem Mass Spectrometry.
J. Agric. Food Chem.
PUBLISHED: 03-25-2014
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An ultrahigh-performance liquid chromatography-tandem mass spectrometry method was developed and validated for the profiling of six folate species in potatoes. The calibration curves cover a wide, linear range (the lower and upper limits of quantitation range between 0.22-0.24 and 216.07-242.28 ?g/100 g of fresh weight), allowing sensitive determination in small amounts of potato flesh. With a single exception, the acceptance criteria for intra- and interday precision and accuracy were met: for all quality controls, the percent relative standard deviation and the percent bias were lower than 15% (or 20% at the lower limit of quantitation). Application of the method on tubers at different stages of maturation demonstrated the large variability within a single variety: the folate content and polyglutamylation rate varied between 10.35 and 24.01 ?g/100 g of fresh weight and between 4.96% and 60.49%, respectively. Additionally, the two-dimensional folate profiling of mature tubers demonstrated an increase in folate from center to peel, combined with a stable species distribution and polyglutamylation rate.
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Genetic causes of male infertility.
Ann. Endocrinol. (Paris)
PUBLISHED: 03-19-2014
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Male infertility, affecting around half of the couples with a problem to get pregnant, is a very heterogeneous condition. Part of patients are having a defect in spermatogenesis of which the underlying causes (including genetic ones) remain largely unknown. The only genetic tests routinely used in the diagnosis of male infertility are the analyses for the presence of Yq microdeletions and/or chromosomal abnormalities. Various other single gene or polygenic defects have been proposed to be involved in male fertility. Yet, their causative effect often remains to be proven. The recent evolution in the development of whole genome-based techniques may help in clarifying the role of genes and other genetic factors involved in spermatogenesis and spermatogenesis defects.
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Retrospective serology study of respiratory virus infections in captive great apes.
Viruses
PUBLISHED: 03-14-2014
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Great apes are extremely sensitive to infections with human respiratory viruses. In this study, we retrospectively analyzed sera from captive chimpanzees, gorillas and orang-utans. More than 1000 sera (403 chimpanzee, 77 gorilla, and 535 orang-utan sera) were analyzed for antibodies to the human respiratory viruses RSV (respiratory syncytial virus, hMPV (human metapneumovirus), H1N1 and H3N2 influenza A viruses, and influenza B virus. In all ape species high seroprevalences were found for RSV, hMPV, and influenza B virus. A high percentage of captive chimpanzees also showed evidence of influenza A H1N1 infections, and had low levels of H3N2 antibodies, while in sera from gorillas and orangutans antibody levels to influenza A and B viruses were much lower or practically absent. Transmission of respiratory viruses was examined in longitudinal sera of young chimpanzees, and in chimpanzee sera taken during health checks. In young animals isolated cases of influenza infections were monitored, but evidence was found for single introductions followed by a rapid dissemination of RSV and hMPV within the group. Implementation of strict guidelines for handling and housing of nonhuman primates was shown to be an efficient method to reduce the introduction of respiratory infections in colonies of captive animals. RSV seroprevalence rates of chimpanzees remained high, probably due to circulating virus in the chimpanzee colony.
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Uptake and metabolism of D-glucose in isolated acinar and ductal cells from rat submandibular glands.
Cell Biochem. Funct.
PUBLISHED: 03-06-2014
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The present study deals with the possible effects of selected environmental agents upon the uptake and metabolism of d-glucose in isolated acinar and ductal cells from the rat submandibular salivary gland. In acinar cells, the uptake of d-[U-(14) C]glucose and its non-metabolised analogue 3-O-[(14) C-methyl]-d-glucose was not affected significantly by phloridzin (0.1 mM) or substitution of extracellular NaCl (115 mM) by an equimolar amount of CsCl, whilst cytochalasin B (20 ?M) decreased significantly such an uptake. In ductal cells, both phloridzin and cytochalasin B decreased the uptake of d-glucose and 3-O-methyl-d-glucose. Although the intracellular space was comparable in acinar and ductal cells, the catabolism of d-glucose (2.8 or 8.3 mM) was two to four times higher in ductal cells than in acinar cells. Phloridzin (0.1 mM), ouabain (1.0 mM) and cytochalasin B (20 ?M) all impaired d-glucose catabolism in ductal cells. Such was also the case in ductal cells incubated in the absence of extracellular Ca(2+) or in media in which NaCl was substituted by CsCl. It is proposed that the ductal cells in the rat submandibular gland are equipped with several systems mediating the insulin-sensitive, cytochalasin B-sensitive and phloridzin-sensitive transport of d-glucose across the plasma membrane.
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Incidence of severe Dysphagia after brain surgery in pediatric traumatic brain injury: a nationwide population-based retrospective study.
J Head Trauma Rehabil
PUBLISHED: 03-05-2014
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To investigate the incidence of dysphagia and medical resource utilization in a nationwide population of pediatric patients with traumatic brain injury (TBI).
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Expression and localization of glucose transporters in rodent submandibular salivary glands.
Cell. Physiol. Biochem.
PUBLISHED: 02-20-2014
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The submandibular gland is one of the three major salivary glands, producing a mixed secretion; this saliva is hypotonic compared to plasma. It also secretes glucose, but the mechanisms responsible for this process are poorly understood. Our study addressed the question whether glucose transporters are expressed and how are they localized within specific rodent submandibular cells, in order to estimate a possible implication in salivary glucose disposal.
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Analysis of the whole mitochondrial genome: translation of the Ion Torrent Personal Genome Machine system to the diagnostic bench?
Eur. J. Hum. Genet.
PUBLISHED: 02-14-2014
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Next-generation sequencing (NGS), an innovative sequencing technology that enables the successful analysis of numerous gene sequences in a massive parallel sequencing approach, has revolutionized the field of molecular biology. Although NGS was introduced in a rather recent past, the technology has already demonstrated its potential and effectiveness in many research projects, and is now on the verge of being introduced into the diagnostic setting of routine laboratories to delineate the molecular basis of genetic disease in undiagnosed patient samples. We tested a benchtop device on retrospective genomic DNA (gDNA) samples of controls and patients with a clinical suspicion of a mitochondrial DNA disorder. This Ion Torrent Personal Genome Machine platform is a high-throughput sequencer with a fast turnaround time and reasonable running costs. We challenged the chemistry and technology with the analysis and processing of a mutational spectrum composed of samples with single-nucleotide substitutions, indels (insertions and deletions) and large single or multiple deletions, occasionally in heteroplasmy. The output data were compared with previously obtained conventional dideoxy sequencing results and the mitochondrial revised Cambridge Reference Sequence (rCRS). We were able to identify the majority of all nucleotide alterations, but three false-negative results were also encountered in the data set. At the same time, the poor performance of the PGM instrument in regions associated with homopolymeric stretches generated many false-positive miscalls demanding additional manual curation of the data.European Journal of Human Genetics advance online publication, 26 March 2014; doi:10.1038/ejhg.2014.49.
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Screening and confirmation methods for GHB determination in biological fluids.
Anal Bioanal Chem
PUBLISHED: 02-06-2014
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The purpose of this review is to provide a comprehensive overview of reported methods for screening and confirmation of the low-molecular-weight compound and drug of abuse gamma-hydroxybutyric acid (GHB) in biological fluids. The polarity of the compound, its endogenous presence, its rapid metabolism after ingestion, and its instability during storage (de novo formation and interconversion between GHB and its lactone form gamma-butyrolactone) are challenges for the analyst and for interpretation of a positive result. First, possible screening procedures for GHB are discussed, including colorimetric, enzymatic, and chromatography-based procedures. Confirmation methods for clinical and forensic cases mostly involve gas chromatography (coupled to mass spectrometry), although liquid chromatography and capillary zone electrophoresis have also been used. Before injection, sample-preparation techniques include (a combination of) liquid-liquid, solid-phase, or headspace extraction, and chemical modification of the polar compound. Also simple "dilute-and-shoot" may be sufficient for urine or serum. Advantages, limitations, and trends are discussed.
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Effect of cytochalasin B on 3-O-[(14)C]-methyl-D-glucose or D-[U-(14)C]glucose handling by BRIN-BD11 cells.
Biomed Rep
PUBLISHED: 01-24-2014
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The present study aimed to investigate the effects of cytochalasin B (20 ?M) on the uptake of 3-O-[(14)C]-methyl-D-glucose or D-[U-(14)C]glucose (8.3 mM each) by BRIN-BD11 cells. Taking into account the distribution space of tritiated water ((3)HOH), which was unexpectedly increased shortly after exposure of the cells to cytochalasin B and then progressively returned to its control values, and that of L-[1-(14)C]glucose, used as an extracellular marker, it was demonstrated that cytochalasin B caused a modest, but significant inhibition of the uptake of D-glucose and its non-metabolized analog by the BRIN-BD11 cells. These findings resemble those observed in acinar or ductal cells of the rat submaxillary gland and displayed a relative magnitude comparable to that found for the inhibition of D-glucose metabolism by cytochalasin B in purified pancreatic islet B cells. These findings reinforce the view that the primary site of action of cytochalasin B is located at the level of the plasma membrane.
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Insulin release: the receptor hypothesis.
Diabetologia
PUBLISHED: 01-16-2014
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It is currently believed that the stimulation of insulin release by nutrient secretagogues reflects their capacity to act as fuel in pancreatic islet beta cells. In this review, it is proposed that such a fuel concept is not incompatible with a receptor hypothesis postulating the participation of cell-surface receptors in the recognition of selected nutrients as insulinotropic agents. Pursuant to this, attention is drawn to such matters as the anomeric specificity of the beta cell secretory response to D-glucose and its perturbation in diabetes mellitus, the insulinotropic action of artificial sweeteners, the possible role of bitter taste receptors in the stimulation of insulin secretion by L-glucose pentaacetate, the recently documented presence of cell-surface sweet taste receptors in insulin-producing cells, the multimodal signalling process resulting from the activation of these latter receptors, and the presence in beta cells of a sweet taste receptor mediating the fructose-induced potentiation of glucose-stimulated insulin secretion.
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T? mapping detects pharmacological retardation of diffuse cardiac fibrosis in mouse pressure-overload hypertrophy.
Circ Cardiovasc Imaging
PUBLISHED: 01-14-2014
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Diffuse interstitial fibrosis is present in diverse cardiomyopathies and associated with poor prognosis. We investigated whether magnetic resonance imaging-based T1 mapping could quantify the induction and pharmacological suppression of diffuse cardiac fibrosis in murine pressure-overload hypertrophy.
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Efficacy and safety of rilpivirine-based regimens in treatment-experienced HIV-1 infected patients: a prospective cohort study.
J Int AIDS Soc
PUBLISHED: 01-01-2014
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Rilpivirine (RPV) is a new once-daily, non-nucleoside, reverse transcriptase inhibitor (NNRTI). In treatment-naïve patients, RPV has shown non-inferior antiviral activity to efavirenz but data in treatment-experienced patients are more limited. We assessed the efficacy and safety of RPV in treatment-experienced patients switching to a RPV-based regimen.
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Vaccine-Induced Protection of Rhesus Macaques against Plasma Viremia after Intradermal Infection with a European Lineage 1 Strain of West Nile Virus.
PLoS ONE
PUBLISHED: 01-01-2014
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The mosquito-borne West Nile virus (WNV) causes human and animal disease with outbreaks in several parts of the world including North America, the Mediterranean countries, Central and East Europe, the Middle East, and Africa. Particularly in elderly people and individuals with an impaired immune system, infection with WNV can progress into a serious neuroinvasive disease. Currently, no treatment or vaccine is available to protect humans against infection or disease. The goal of this study was to develop a WNV-vaccine that is safe to use in these high-risk human target populations. We performed a vaccine efficacy study in non-human primates using the contemporary, pathogenic European WNV genotype 1a challenge strain, WNV-Ita09. Two vaccine strategies were evaluated in rhesus macaques (Macaca mulatta) using recombinant soluble WNV envelope (E) ectodomain adjuvanted with Matrix-M, either with or without DNA priming. The DNA priming immunization was performed with WNV-DermaVir nanoparticles. Both vaccination strategies successfully induced humoral and cellular immune responses that completely protected the macaques against the development of viremia. In addition, the vaccine was well tolerated by all animals. Overall, The WNV E protein adjuvanted with Matrix-M is a promising vaccine candidate for a non-infectious WNV vaccine for use in humans, including at-risk populations.
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A bumpy ride on the diagnostic bench of massive parallel sequencing, the case of the mitochondrial genome.
PLoS ONE
PUBLISHED: 01-01-2014
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The advent of massive parallel sequencing (MPS) has revolutionized the field of human molecular genetics, including the diagnostic study of mitochondrial (mt) DNA dysfunction. The analysis of the complete mitochondrial genome using MPS platforms is now common and will soon outrun conventional sequencing. However, the development of a robust and reliable protocol is rather challenging. A previous pilot study for the re-sequencing of human mtDNA revealed an uneven coverage, affecting predominantly part of the plus strand. In an attempt to address this problem, we undertook a comparative study of standard and modified protocols for the Ion Torrent PGM system. We could not improve strand representation by altering the recommended shearing methodology of the standard workflow or omitting the DNA polymerase amplification step from the library construction process. However, we were able to associate coverage bias of the plus strand with a specific sequence motif. Additionally, we compared coverage and variant calling across technologies. The same samples were also sequenced on a MiSeq device which showed that coverage and heteroplasmic variant calling were much improved.
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Lopinavir/r no longer recommended as a first-line regimen: a comparative effectiveness analysis.
J Int AIDS Soc
PUBLISHED: 01-01-2014
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We compared the effectiveness of tenofovir/emtricitabine (TDF/FTC) combined with either lopinavir/r (LPV/r) or another recommended third drug in the 2010 French guidelines in antiretroviral-naïve patients starting combination antiretroviral therapy in 2004-2008 in the French Hospital Database on HIV.
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Strong vaccine-induced CD8 T-cell responses have cytolytic function in a chimpanzee clearing HCV infection.
PLoS ONE
PUBLISHED: 01-01-2014
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A single correlate of effective vaccine protection against chronic HCV infection has yet to be defined. In this study, we analyzed T-cell responses in four chimpanzees, immunized with core-E1-E2-NS3 and subsequently infected with HCV1b. Viral clearance was observed in one animal, while the other three became chronically infected. In the animal that cleared infection, NS3-specific CD8 T-cell responses were observed to be more potent in terms of frequency and polyfunctionality of cytokine producing cells. Unique to this animal was the presence of killing-competent CD8 T-cells, specific for NS3 1258-1272, being presented by the chimpanzee MHC class I molecule Patr-A*03?01, and a high affinity recognition of this epitope. In the animals that became chronically infected, T-cells were able to produce cytokines against the same peptide but no cytolysis could be detected. In conclusion, in the animal that was able to clear HCV infection not only cytokine production was observed but also cytolytic potential against specific MHC class I/peptide-combinations.
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Nonspecific effects of ligands on the beta-adrenergic receptors in rabbit abdominal aorta in vitro.
Folia Biol. (Krakow)
PUBLISHED: 11-28-2013
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The study was conducted on 30 New Zealand rabbits weighing 3-4 kg from which sample strips of the abdominal aorta were collected. The study investigated the in vitro reaction of rabbit aorta smooth muscle to ligands binding to beta-adrenergic receptors. The response of aortic strips to beta-adrenergic receptor agonists (dobutamine, isoproterenol, salbutamol) and the influence of beta-adrenergic receptor antagonists (propranolol, betaxolol) on contractile activity was determined. All tested agonists induced contraction of the rabbit abdominal aorta muscle in a concentration-dependent manner (dobutamine > isoproterenol > salbutamol). Enhanced reaction to low concentrations of agonists (dobutamine, isoproterenol) after administration of propranolol and inhibition of contractility in the presence of high concentrations thereof (dobutamine, salbutamol) was observed. Maximal reaction to agonists decreased after betaxolol pretreatment. The results indicate that all the substances with beta-agonist activity also possess contracting properties (presumably by acting at alpha-adrenergic receptors), but are much weaker in the case of isoproterenol and salbutamol than for dobutamine. Propranolol and betaxolol reduce the contractile response of smooth muscle using probably other mechanisms than those associated with adrenergic receptors.
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Paracrine control of glucagon release by somatostatin (Review).
Int. J. Mol. Med.
PUBLISHED: 11-25-2013
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Emphasis was recently placed on the modulation of glucagon secretion attributable to a paracrine effect of somatostatin. This review draws attention to prior findings related to such a view. The effects of nutrient secretagogues upon insulin, somatostatin and glucagon release by the perfused pancreas are first considered. Three examples of paradoxical secretory responses of insulin- and glucagon-producing cells are then given. Further experiments dealing with the possible role of somatostatin upon glucagon release and the relevance of pancreatic compartmentation are also presented. It is concluded that these prior findings provide, within limits, support to the postulated paracrine role of somatostatin in the control of glucagon secretion.
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Subtelomeric chromosomal rearrangements in a large cohort of unexplained intellectually disabled individuals in Indonesia: A clinical and molecular study.
Indian J Hum Genet
PUBLISHED: 09-11-2013
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Unbalanced subtelomeric chromosomal rearrangements are often associated with intellectual disability (ID) and malformation syndromes. The prevalence of such rearrangements has been reported to be 5-9% in ID populations.
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[Minimally invasive access to the abdominal aorta in pigs].
Prz. Lek.
PUBLISHED: 09-06-2013
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Experiments were conducted on 10 sows weighing 50-60 kg. Animals were randomly divided into two experimental groups comprising 5 individuals each. Surgical procedure of reaching the abdominal aorta below the renal arteries was performed using two different methods. In animals from the first group the procedure involved cutting the linea alba in order to obtain access to the abdominal aorta through the abdominal cavity. In the second group the access to the abdominal aorta was obtained by retroperitoneal approach. The approach was made in lower lateral one-third of the abdomen cutting through the muscles and without opening the peritoneal cavity. The study showed superiority of the second surgical method over the median approach along the linea alba in the form of: better animal survival (100% of animals), shorter procedure time, lack of postoperative complications, shorter recovery period and better general postoperative condition
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[Effect of atherosclerotic plaque on the contractility of human abdominal aorta sections].
Prz. Lek.
PUBLISHED: 09-06-2013
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The study was performed on 18 sections of the aneurysm-like abdominal aorta sampled during elective procedures of aneurysm correction in humans, and 10 sections of pig abdominal aorta. We examined the extent to which the presence of atherosclerotic plaque impaired the aorta contractile function and measured the thickness and weight of atherosclerosis plaque and arterial wall. We observed reduced tissue response to adrenaline in human aneurysm-like aorta in comparison to the control group. In the sections of human aorta devoid of atherosclerotic plaque the response to adrenaline was about 30% higher than in those with atherosclerotic changes but 35% lower than in normal aorta sections from pigs. The wall of aneurysm-like human aorta sections was thinner when compared to normal aorta.
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Hemato-critical issues in quantitative analysis of dried blood spots: challenges and solutions.
Bioanalysis
PUBLISHED: 08-14-2013
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Dried blood spot (DBS) sampling for quantitative determination of drugs in blood has entered the bioanalytical arena at a fast pace during the last decade, primarily owing to progress in analytical instrumentation. Despite the many advantages associated with this new sampling strategy, several issues remain, of which the hematocrit issue is undoubtedly the most widely discussed challenge, since strongly deviating hematocrit values may significantly impact DBS-based quantitation. In this review, an overview is given of the different aspects of the hematocrit problem in quantitative DBS analysis. The different strategies that try to cope with this problem are discussed, along with their potential and limitations. Implementation of some of these strategies in practice may help to overcome this important hurdle in DBS assays, further allowing DBS to become an established part of routine quantitative bioanalysis.
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Heterogeneity in lung (18)FDG uptake in pulmonary arterial hypertension: potential of dynamic (18)FDG positron emission tomography with kinetic analysis as a bridging biomarker for pulmonary vascular remodeling targeted treatments.
Circulation
PUBLISHED: 07-30-2013
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Pulmonary arterial hypertension (PAH) is a disease of progressive vascular remodeling, characterized by dysregulated growth of pulmonary vascular cells and inflammation. A prevailing view is that abnormal cellular metabolism, notably aerobic glycolysis that increases glucose demand, underlies the pathogenesis of PAH. Increased lung glucose uptake has been reported in animal models. Few data exist from patients with PAH.
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2D versus 3D roadmap for uterine artery catheterization: impact on several angiographic parameters.
Acta Radiol
PUBLISHED: 07-19-2013
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Three-dimensional (3D) roadmap is a recently developed imaging technique used to guide diagnostic and interventional catheter-directed procedures and mainly evaluated for neurovascular procedures. Few data with regard to efficacy and radiation dose are currently available in literature.
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Comparison of the effect of alpha1- and alpha2-adrenoceptor agonists and antagonists on muscle contractility of the rabbit abdominal aorta in vitro.
Folia Biol. (Krakow)
PUBLISHED: 06-18-2013
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The aim of the study was to demonstrate the effect of selected agonists and antagonists of alpha-adrenergic receptors on muscle contractility of the rabbit abdominal aorta in vitro with particular emphasis on alpha2-adrenergic receptor subtypes. The study was conducted on 30 New Zealand breed rabbits from which specimens of the abdominal aorta were collected. The sections were set up in an automatic water bath in a Krebs-Henseleit buffer at 37 degrees C. The experiments showed that alpha1-adrenergic receptors played the main role in the contractile response ofthe rabbit abdominal aorta. Stimulation of alpha1-adrenergic receptor by administration ofphenylephrine resulted in an increase in smooth muscle tonus ofthe rabbit abdominal aorta by an average of 4.75 mN. The reaction after stimulation of alpha2-adrenergic receptors by similar doses of their agonists was much weaker. Prolonged tissue response time and time needed to reach maximum tonus for alpha2-adrenergic receptor agonists were observed. The obtained results confirm the thesis that the alpha1-adrenergic receptor is the most important factor controlling the contractility of the rabbit abdominal aorta, but the alpha2-adrenergic receptor is also involved in maintaining muscle tissue tonus.
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Hair ethyl glucuronide levels as a marker for alcohol use and abuse: A review of the current state of the art.
Drug Alcohol Depend
PUBLISHED: 05-27-2013
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Ethyl glucuronide (EtG) is a minor alcohol metabolite that has been proposed as a stable marker in hair to detect and quantify alcohol consumption over long time periods.
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Challenges and opportunities for oral pre-exposure prophylaxis in the prevention of HIV infection: where are we in Europe?
BMC Med
PUBLISHED: 05-21-2013
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Following US Food and Drugs Administration approval in July 2012 of daily oral tenofovir and emtricitabine for pre-exposure prophylaxis (PrEP) to prevent HIV infection in high-risk individuals in the USA, there has been much controversy about the implementation of this PrEP regimen in other countries throughout the world, and in Europe in particular. In this review, we focus on the challenges and opportunities of a daily oral PrEP regimen to curb the rising incidence of HIV infection in high-risk groups, and particularly in men who have sex with men. A number of issues would need to be addressed before PrEP could be implemented, including assessing the real effectiveness and cost-effectiveness of daily PrEP, the sustainability of daily adherence, the risk of selecting resistance, the long-term safety, and the risk of change in sexual behavior that might offset the benefit of PrEP. Alternatives to a daily oral PrEP regimen are being explored.
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Early myoclonic epilepsy, hypertrophic cardiomyopathy and subsequently a nephrotic syndrome in a patient with CoQ10 deficiency caused by mutations in para-hydroxybenzoate-polyprenyl transferase (COQ2).
Eur. J. Paediatr. Neurol.
PUBLISHED: 05-15-2013
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Primary coenzyme Q10 (CoQ10) deficiencies are heterogeneous autosomal recessive disorders. CoQ2 mutations have been identified only rarely in patients. All affected individuals presented with nephrotic syndrome in the first year of life.
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Characterization of CoQ10 biosynthesis in fibroblasts of patients with primary and secondary CoQ10 deficiency.
J. Inherit. Metab. Dis.
PUBLISHED: 05-13-2013
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Primary coenzyme Q10 (CoQ10) deficiencies are associated with mutations in genes encoding enzymes important for its biosynthesis and patients are responsive to CoQ10 supplementation. Early treatment allows better prognosis of the disease and therefore, early diagnosis is desirable. The complex phenotype and genotype and the frequent secondary CoQ10 deficiencies make it difficult to achieve a definitive diagnosis by direct quantification of CoQ10. We developed a non-radioactive methodology for the quantification of CoQ10 biosynthesis in fibroblasts that allows the identification of primary deficiencies. Fibroblasts were incubated 72 h with 28 ?mol/L (2)H3-mevalonate or 1.65 mmol/L (13)C6-p-hydroxybenzoate. The newly synthesized (2)H3- and (13)C6- labelled CoQ10 were analysed by high performance liquid chromatography-tandem mass spectrometry. The mean and the reference range for (13)C6-CoQ10 and (2)H3-CoQ10 biosynthesis were 0.97 (0.83-1.1) and 0.13 (0.09-0.17) nmol/Unit of citrate synthase, respectively. We validated the methodology through the study of one patient with COQ2 mutations and six patients with CoQ10 deficiency secondary to other inborn errors of metabolism. Afterwards we investigated 16 patients fibroblasts and nine showed decreased CoQ10 biosynthesis. Therefore, the next step is to study the COQ genes in order to reach a definitive diagnosis in these nine patients. In the patients with normal rates the deficiency is probably secondary. In conclusion, we have developed a non-invasive non-radioactive method suitable for the detection of defects in CoQ10 biosynthesis, which offers a good tool for the stratification of patients with these treatable mitochondrial diseases.
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GATAD2B loss-of-function mutations cause a recognisable syndrome with intellectual disability and are associated with learning deficits and synaptic undergrowth in Drosophila.
J. Med. Genet.
PUBLISHED: 05-04-2013
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GATA zinc finger domain containing 2B (GATAD2B) encodes a subunit of the MeCP1-Mi-2/nucleosome remodelling and deacetylase complex involved in chromatin modification and regulation of transcription. We recently identified two de novo loss-of-function mutations in GATAD2B by whole exome sequencing in two unrelated individuals with severe intellectual disability.
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A tentative model for (D)-glucose turnover in human saliva.
Arch. Oral Biol.
PUBLISHED: 04-17-2013
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The aim of the present study is to propose a tentative model for d-glucose turnover in human saliva. The whole saliva and the saliva from parotid and submandibular/sublingual glands were collected by use of the Salivette™.
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Phytochemical screening and free radical scavenging activity of Citrullus colocynthis seeds extracts.
Asian Pac J Trop Biomed
PUBLISHED: 04-10-2013
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To study the phytochemical screening of different extracts from Citrullus colocynthis (C. colocynthis ) seeds extracts and to assess their antioxidant activity on the DPPH free radical scavenging.
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Immunocytochemistry of GLUT2, uptake of fluorescent desnitroso-streptozotocin analogs and phosphorylation of D-glucose in INS-1E cells.
Mol Med Rep
PUBLISHED: 03-27-2013
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The non-invasive imaging of GLUT2-expressing cells remains a challenge. As streptozotocin, and similarly alloxan, may be transported into cells by GLUT2, the major aim of the present study was to assess the possible use of fluorescent desnitroso-streptozotocin analogs for in vitro labeling of GLUT2-expressing cells. INS-1E cells, human embryonic kidney (HEK) cells, rat isolated pancreatic islets, rat hepatic cells, rat exocrine pancreatic cells and tumoral insulin-producing BRIN-BD11 cells were incubated in the presence of two distinct fluorescent desnitroso-streptozotocin analogs, probes A and B. The immunocytochemistry of GLUT2 in INS-1E cells and the phosphorylation of D-glucose by INS-1E cell homogenates were also examined. The uptake of probes A and B (12.0 µM) by INS-1E cells yielded apparent intracellular concentrations approximately one order of magnitude higher than the extracellular concentration. The two probes differed from one another by the absolute values for their respective uptake and time course, but not so by the pattern of their concentration dependency. Comparable results were recorded in HEK cells, rat isolated pancreatic islets and hepatocytes. Vastly different findings were recorded, however, in rat exocrine pancreatic cells, which do not express GLUT2. Moreover, an unusual concentration dependency for the uptake of each probe was observed in tumoral BRIN-BD11 cells. It is proposed that suitable fluorescent desnitroso-streptozotocin analogs may be used to label GLUT2-expressing cells.
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D-glucose? and 3-O-methyl-D-glucose-induced upregulation of selected genes in rat hepatocytes and INS1E cells: re?evaluation of the possible role of hexose phosphorylation.
Mol Med Rep
PUBLISHED: 03-12-2013
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The biochemical events involved in the upregulation of selected glucose?responsive genes by 3?O?methyl?D?glucose (3?MG) remain to be elucidated. The present study mainly aimed to re?evaluate the possible role of 3?MG phosphorylation in the upregulation of the thioredoxin interacting protein (TXNIP) and liver pyruvate kinase (LPK) genes in rat hepatocytes and INS1E cells. TXNIP and LPK transcription was assessed in rat liver and INS1E cells exposed to a rise in D?glucose concentration, 2?deoxy?D?glucose (2?DG), 3?MG and, when required, D?mannoheptulose. The phosphorylation of D?[U?14C]glucose and 3?O?[14C]methyl?D?glucose (14C-labeled 3-MG) was measured in rat liver, INS1E cell and rat pancreatic islet homogenates. The utilization of D?[5?3H]glucose by intact INS1E cells was also measured. In rat hepatocytes, a rise in the D?glucose concentration increased the TXNIP/hypoxanthine?guanine phosphoribosyl transferase (HPRT) and LPK/HPRT ratios, while 2?DG and 3?MG also increased the TXNIP/HPRT ratio, but not the LPK/HPRT ratio. In INS1E cells, the TXNIP/HPRT and LPK/HPRT ratios were increased in response to the addition of D?glucose, 2?DG and 3?MG. Furthermore, D?mannoheptulose abolished the response to D?glucose and 2?DG, but not to 3?MG, in these cells. Liver cell homogenates catalyzed the phosphorylation of 3?MG to a modest extent, whilst INS1E and rat pancreatic islet cell homogenates did not. Moreover, 3?MG marginally decreased D?glucose phosphorylation in INS1E cell homogenates but not in liver cell homogenates. D?[5?3H]glucose utilization by intact INS1E cells was decreased by 2?DG, but not by 3?MG. These findings reinforce the view that the upregulation of the TXNIP and LPK genes induced by 3?MG is not attributable to its phosphorylation or any favorable effect on D?glucose metabolism.
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Feasibility of following up gamma-hydroxybutyric acid concentrations in sodium oxybate (Xyrem®)-treated narcoleptic patients using dried blood spot sampling at home: an exploratory study.
CNS Drugs
PUBLISHED: 03-07-2013
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Gamma-hydroxybutyric acid (GHB), well known as a party drug, especially in Europe, is also legally used (sodium oxybate, Xyrem(®)) to treat a rare sleep disorder, narcolepsy with cataplexy. This exploratory study was set up to measure GHB concentrations in dried blood spots (DBS) collected by narcoleptic patients treated with sodium oxybate. Intra- and inter-individual variation in clinical effects following sodium oxybate administration has been reported. The use of DBS as a sampling technique, which is stated to be easy and convenient, may provide a better insight into GHB concentrations following sodium oxybate intake in a real-life setting.
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Effect of Resveratrol on Cultured Skin Fibroblasts from Patients with Oxidative Phosphorylation Defects.
Phytother Res
PUBLISHED: 02-26-2013
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Few therapeutic options are available to patients with oxidative phosphorylation disorders. Administering pharmacological agents that are able to stimulate mitochondrial biogenesis have been put forward as a possible treatment, yet the approach remains in need of thorough testing. We investigated the effect of resveratrol in an in vitro setting. Mitochondrial enzymatic activities were tested in cultured skin fibroblasts from patients harboring a nuclear defect in either complex II or complex IV (n?=?11), and in fibroblasts from healthy controls (n?=?11). In the latter, preincubation with resveratrol resulted in a significant increase of citrate synthase, complex II and complex IV enzyme activity. In patients with complex II or complex IV deficiency, however, activity of the deficient complex could not be substantially augmented, and response was dependent upon the residual activity. We conclude that resveratrol is not capable of normalizing oxidative phosphorylation activities in deficient cell lines. Copyright © 2013 John Wiley & Sons, Ltd.
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Interaction between cAMP, volume?regulated anion channels and the Na+?HCO3??cotransporter, NBCe1, in the regulation of nutrient? and hypotonicity?induced insulin release from isolated rat pancreatic islets and tumoral insulin?producing BRIN?BD11 cells.
Mol Med Rep
PUBLISHED: 02-22-2013
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Soluble adenylyl cyclase (sAC) has been hypothesized to play a role in insulin secretion. The present study aimed to investigate the interaction between adenosine 3,5?cyclic monophosphate (cAMP), volume?regulated anion channels (VRACs) and the electrogenic sodium bicarbonate (Na+?HCO3?) cotransporter, NBCe1, in the regulation of nutrient? and hypotonicity?induced insulin release from rat pancreatic islets and tumoral insulin?producing BRIN?BD11 cells. In the islets, 5?nitro?2?(3?phenylpropylamino)benzoic acid (NPPB) and 5?chloro?2?hydroxy?3?(thiophene?2?carbonyl)indole?1?carboxamide (tenidap) reduced glucose?stimulated insulin release, however, only NPPB suppressed the enhancing action of cAMP analogs upon such a release. Insulin output from the BRIN?BD11 cells was stimulated by 2?ketoisocaproate (KIC) or extracellular hypoosmolarity. cAMP analogs and 3?isobutyl?1?methylxanthine increased the insulin output recorded in the isotonic medium to a greater relative extent than that in the hypotonic medium. The secretory response to KIC or hypotonicity was inhibited by NPPB or tenidap, which both also opposed the enhancing action of cAMP analogs. Inhibitors of mitogen?activated protein (MAP) kinase decreased insulin output in isotonic and hypotonic media. The inhibitor of sAC, 2?hydroxyestriol, caused only a modest inhibition of insulin release, whether in the isotonic or hypotonic medium, even when tested at a concentration of 100 µM. The omission of NaHCO3 markedly decreased the secretory response to KIC or extracellular hypotonicity. The omission of Na+ suppressed the secretory response to extracellular hypotonicity. The observations of the present study do not support the hypothesis of a major role for sAC in the regulation of insulin release.
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Determination of gamma-hydroxybutyric acid in biofluids using a one-step procedure with "in-vial" derivatization and headspace-trap gas chromatography-mass spectrometry.
J Chromatogr A
PUBLISHED: 02-21-2013
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A headspace-trap gas chromatography-mass spectrometry (HS-trap GC-MS) method was developed to determine GHB, a low molecular weight compound and drug of abuse, in various biological fluids. Combining this relatively novel and fully automated headspace technique with "in-vial" methylation of GHB allowed for a straightforward approach. One single method could be used for all biofluids (urine, plasma, serum, whole blood or lyzed blood), requiring only 100?l of sample. Moreover, our approach involves mere addition of all reagents and sample into one vial. Following optimization of headspace conditions and trap settings, validation was performed. Although sample preparation only consists of the addition of salt and derivatization reagents directly to a 100?l-sample in a HS-vial, adequate method sensitivity and selectivity was obtained. Calibration curves ranged from 5 to 150?g/ml GHB for urine, from 2 to 150?g/ml for plasma, and from 3.5 to 200?g/ml for whole blood. Acceptable precision and accuracy (<13% bias and imprecision) were seen for all quality controls (QCs) (LLOQ-level, low, medium, high), including for the supplementary serum- and lyzed blood-based QCs, using calibration curves prepared in plasma or whole blood, respectively. Incurred sample reanalysis demonstrated assay reproducibility, while cross-validation with another GC-MS method demonstrated that our method is a valuable alternative for GHB determination in toxicological samples, with the advantage of requiring only 100?l and minimal hands-on time, as sample preparation is easy and injection automated.
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