Miracle-dz/UniFAR-FTUs huggingface dataset:
Action potential generation in rat slow‐ and fast‐twitch muscles.

1. In skeletal muscle fibres, voltage‐gated sodium channels are concentrated at the neuromuscular junction. The effect of this accumulation of sodium channels on action potential generation was investigated in rat slow‐ and fast‐twitch muscle fibres. 2. Intracellular microelectrodes were used to generate and record action potentials, from an imposed membrane potential of ‐75 and ‐90 mV, in junctional and extrajunctional regions of the muscle fibre. To identify junctional regions, preparations were incubated with 5 x 10(‐7) M d‐tubocurarine (dTC) to block muscle contraction in response to nerve stimulation whilst allowing endplate potentials (EPPs) to be recorded. Injection of rectangular depolarizing current pulses initiated action potentials at the endplate with threshold values several millivolts lower than those generated elsewhere in the fibre. In addition, the maximum rate of rise of the action potential was greater at the endplate than in extrajunctional regions. 3. In other muscles, neuromuscular transmission was partially blocked with dTC (2 x 10(‐7) M), such that repetitive nerve stimulation evoked action potentials and EPPs in the same fibre. The threshold of these nerve‐evoked action potentials was approximately 50% lower than values derived from action potentials generated by current injection. 4. It is concluded that the threshold for action potential generation is significantly lower at the neuromuscular junction than in extrajunctional regions of skeletal muscle fibres. Furthermore, nerve‐evoked current is more effective at generating an action potential than is injected current.
Fluoxetine response in impulsive–aggressive behavior and serotonin transporter polymorphism in personality disorder

Background Disturbances in central serotonin function have been implicated in impulsive and aggressive behavior. A deletion/insertion polymorphism within the 5-HT transporter promoter gene (5-HTTLPR) is thought to be associated with disturbed impulse control, anxiety, and depression. The serotonin transporter (5-HTT) is the primary action site for selective serotonin reuptake inhibitors (SSRIs). Several studies of major depression have shown that the l allele of 5-HTTLPR is associated with better SSRI antidepressant effects than the s allele. Methods This study investigates the association between response of impulsivity to treatment with fluoxetine and 5-HTTLPR polymorphism in 49 personality disordered patients. Additionally, we studied TPH1, 5HT1B and 5HT2C receptor polymorphisms as predictors of response in this population. Results Results reveal that patients with the l/l genotype of 5-HTTLPR had a significantly better response to fluoxetine when compared to s allele carriers, as evaluated on the basis of total (P<0.05) and Aggression subscale (P<0.01) Overt Aggression Scale Modified-score percentage change. There were no significant associations between fluoxetine response and TPH1 (A218C) (−6525 A>G) (−5806 G>T), HTR1B (G861C) and HTR2C (G68C) genotype groups. Conclusion This is the first study assessing the association between these polymorphisms and anti-impulsive response to fluoxetine in personality disorder. As the s genotype is associated with a poorer selective serotonin reuptake inhibitors response in major depression, bulimia nervosa and borderline personality disorder, it could represent a common biological background for SSRI response.
Nitrous Oxide Anesthesia and Plasma Homocysteine in Adolescents

BACKGROUND:Nitrous oxide inactivates vitamin B12, inhibits methionine synthase, and consequently increases plasma total homocysteine (tHcy). Prolonged exposure to nitrous oxide can lead to neuropathy, spinal cord degeneration, and even death in children. We tested the hypothesis that nitrous oxide anesthesia causes a significant increase in plasma tHcy in children. METHODS:Twenty-seven children (aged 10–18 years) undergoing elective major spine surgery were enrolled, and serial plasma samples from 0 to 96 hours after induction were obtained. The anesthetic regimen, including the use of nitrous oxide, was at the discretion of the anesthesiologist. Plasma tHcy was measured using standard enzymatic assays. RESULTS:The median baseline plasma tHcy concentration was 5.1 &mgr;mol/L (3.9–8.0 &mgr;mol/L, interquartile range) and increased in all patients exposed to nitrous oxide (n = 26) by an average of +9.4 &mgr;mol/L (geometric mean; 95% confidence interval, 7.1–12.5 &mgr;mol/L) or +228% (mean; 95% confidence interval, 178%–279%). Plasma tHcy peaked between 6 and 8 hours after induction of anesthesia. One patient who did not receive nitrous oxide had no increase in plasma tHcy. Several patients experienced a severalfold increase in plasma tHcy (maximum +567%). The increase in plasma tHcy was strongly correlated with the duration and average concentration of nitrous oxide anesthesia (r = 0.80; P < 0.001). CONCLUSIONS:Pediatric patients undergoing nitrous oxide anesthesia develop significantly increased plasma tHcy concentrations. The magnitude of this effect seems to be greater compared with adults; however, the clinical relevance is unknown.
Stimulated Brillouin Scattering in a Single-Mode Tellurite Fiber for Amplification, Lasing, and Slow Light Generation

In this paper, Brillouin gain performances of tellurite fiber are investigated for photonics applications. We demonstrate stimulated Brillouin amplification and lasing and the simulated performance of slow light generation in a single-mode tellurite fiber. A Brillouin gain of 29 dB is achieved in a 100-m tellurite fiber with a pump power of 10 mW at 1550 nm. A peak value of Brillouin gain coefficients of 1.6989 X 10-10 m/W is measured on the base of gain characteristics. An all-fiber Brillouin laser with the maximum unsaturated power of 54.6 mW at 1550 nm and a slope efficiency of 38.2% is achieved from a 200-m tellurite fiber by employing a ring cavity. Furthermore, widely tunable (~27 nm) Brillouin comb laser with 26 lines spaced at 7.97 GHz is obtained from the ring laser cavity including an erbium-doped fiber amplifier (EDFA). A simple theoretical model based on laser threshold theory successfully explains the properties of Brillouin comb lasers. Stimulated Brillouin scattering (SBS)-induced time delay per unit power and per unit length is also calculated using the measured data of Brillouin gain coefficients. A peak value of 0.09246 ns/mW/m and a time delay slope efficiency of 1.75 ns/dB are obtained for this tellurite fiber. Potential performance of a tellurite fiber for slow light generation is clarified on the base of Brillouin gain characteristic. Our results show that tellurite fiber is a promising gain medium for Brillouin fiber amplifiers, lasers, and slow light generation due to its low background loss and large Brillouin gain coefficient.
The effect of protein kinase C and its alpha subtype on human vascular smooth muscle cell proliferation, migration and fibronectin production.

BACKGROUND Vascular smooth muscle cell (SMC) migration, proliferation and extracellular matrix protein production are key steps in the formation of intimal hyperplasia, a process that leads to failure of vascular reconstructions. Protein kinase C (PKC) may be involved in all 3 cellular events. PKC consists of a family of 11 isotypes, 8 of which we have identified in human vascular SMCs. In this study we evaluate the role of PKCalpha as a second messenger for proliferation, migration and fibronectin production induced by human saphenous vein SMCs. METHODS DNA synthesis was evaluated by using (3)H-thymidine incorporation. Mitogen-activated protein kinase (MAP-K) activation was quantified by Western blotting with an antibody to its phosphorylated substrate, Elk-1. Chemotaxis was evaluated by using a microchemotaxis chamber. SMC fibronectin was measured by Western blotting. For all experiments, PKCalpha was blocked with a selective inhibitor, Gö6976. RESULTS Gö6976, at concentrations that allow selective inhibition of PKCalpha, inhibited platelet-derived growth factor-stimulated SMC proliferation and MAP-K activation by 30% to 40% and 30% to 60%, respectively. SMC chemotaxis was stimulated approximately 2-fold by the PKCalpha inhibitor. Neither basal nor transforming growth factor-betaI induced fibronectin production was affected by Gö6976. CONCLUSIONS Our data suggest that PKCalpha is a positive mediator of SMC proliferation and MAP-K activity, a negative regulator of migration and has no effect on SMC fibronectin production. These data suggest that modulating activities of specific PKC isotypes might be useful in both the study and control of intimal hyperplasia.
Soluble Prion Protein Inhibits Amyloid-β (Aβ) Fibrillization and Toxicity*

Background: Prion protein was found to interact with Aβ, but the consequences of this interaction are largely unknown. Results: Prion protein and its N-terminal fragment inhibit Aβ1–42 amyloidogenesis and cytotoxicity. Conclusion: Soluble prion protein is a potent inhibitor of Aβ1–42 assembly into toxic oligomers. Significance: The results have important implications for understanding the pathogenesis of AD and for the development of novel therapeutic strategies. The pathogenesis of Alzheimer disease appears to be strongly linked to the aggregation of amyloid-β (Aβ) peptide and, especially, formation of soluble Aβ1–42 oligomers. It was recently demonstrated that the cellular prion protein, PrPC, binds with high affinity to these oligomers, acting as a putative receptor that mediates at least some of their neurotoxic effects. Here we show that the soluble (i.e. glycophosphatidylinositol anchor-free) prion protein and its N-terminal fragment have a strong effect on the aggregation pathway of Aβ1–42, inhibiting its assembly into amyloid fibrils. Furthermore, the prion protein prevents formation of spherical oligomers that normally occur during Aβ fibrillogenesis, acting as a potent inhibitor of Aβ1–42 toxicity as assessed in experiments with neuronal cell culture. These findings may provide a molecular level foundation to explain the reported protective action of the physiologically released N-terminal N1 fragment of PrPC against Aβ neurotoxicity. They also suggest a novel approach to pharmacological intervention in Alzheimer disease.
Biological and rearing mother influences on child ADHD symptoms: revisiting the developmental interface between nature and nurture.

BACKGROUND Families of children with attention deficit hyperactivity disorder (ADHD) report more negative family relationships than families of children without ADHD. Questions remain as to the role of genetic factors underlying associations between family relationships and children's ADHD symptoms, and the role of children's ADHD symptoms as an evocative influence on the quality of relationships experienced within such families. Utilizing the attributes of two genetically sensitive research designs, the present study examined associations between biologically related and nonbiologically related maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. The combined attributes of the study designs permit assessment of associations while controlling for passive genotype-environment correlation and directly examining evocative genotype-environment correlation (rGE); two relatively under examined confounds of past research in this area. METHODS A cross-sectional adoption-at-conception design (Cardiff IVF Study; C-IVF) and a longitudinal adoption-at-birth design (Early Growth and Development Study; EGDS) were used. The C-IVF sample included 160 mothers and children (age 5-8 years). The EGDS sample included 320 linked sets of adopted children (age 6 years), adoptive-, and biologically related mothers. Questionnaires were used to assess maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. A cross-rater approach was used across measures of maternal behavior (mother reports) and child ADHD symptoms (father reports). RESULTS Significant associations were revealed between rearing mother ADHD symptoms, hostile parenting behavior, and child ADHD symptoms in both samples. Because both samples consisted of genetically unrelated mothers and children, passive rGE was removed as a possible explanatory factor underlying these associations. Further, path analysis revealed evidence for evocative rGE processes in the longitudinal adoption-at-birth study (EGDS) from biologically related maternal ADHD symptoms to biologically unrelated maternal hostile parenting through early disrupted child behavior (impulsivity/activation), with maternal hostile parenting and disrupted child behavior associated with later child ADHD symptoms, controlling for concurrent adoptive mother ADHD symptoms. CONCLUSIONS Results highlight the importance of genetically influenced child ADHD-related temperamental attributes on genetically unrelated maternal hostility that in turn links to later child ADHD symptoms. Implications for intervention programs focusing on early family processes and the precursors of child ADHD symptoms are discussed.
A bacterial elongation factor G homologue exclusively functions in ribosome recycling in the spirochaete Borrelia burgdorferi

Translation elongation factor G (EF‐G) in bacteria plays two distinct roles in different phases of the translation system. EF‐G catalyses the translocation of tRNAs on the ribosome in the elongation step, as well as the dissociation of the post‐termination state ribosome into two subunits in the recycling step. In contrast to this conventional view, it has very recently been demonstrated that the dual functions of bacterial EF‐G are distributed over two different EF‐G paralogues in human mitochondria. In the present study, we show that the same division of roles of EF‐G is also found in bacteria. Two EF‐G paralogues are found in the spirochaete Borrelia burgdorferi, EF‐G1 and EF‐G2. We demonstrate that EF‐G1 is a translocase, while EF‐G2 is an exclusive recycling factor. We further demonstrate that B. burgdorferi EF‐G2 does not require GTP hydrolysis for ribosome disassembly, provided that translation initiation factor 3 (IF‐3) is present in the reaction. These results indicate that two B. burgdorferi EF‐G paralogues are close relatives to mitochondrial EF‐G paralogues rather than the conventional bacterial EF‐G, in both their phylogenetic and biochemical features.
Polycystic ovary syndrome: relationship between insulin sensitivity ,sex hormone levels and ovarian stromal blood flow

Polycystic ovary syndrome (PCOS) is the most common cause of menstrual disorders ,and is characterized by chronic anovulation ,hyperandrogenism and infertility. In recent years ,it has become apparent that PCOS is also associated with hyperinsulinemia that is probably central to the pathogenesis of PCOS. As a peculiar vascular pattern has been reported to be present in PCOS ,the aim of this study was to investigate intraovarian stromal vascularization in PCOS patients and its possible correlation with sex hormones ,gonadotropins and insulin levels. Twenty-eight oligomenorrheic or amenorrheic patients with PCOS and 14 eumenorrheic women with a PCOS-like ovarian pattern undergoing endocrine screening and ultrasound color Doppler intraovarian blood flow were recruited to the study. Ten healthy women with regular menses represented the control group. Hormonal assays (follicle-stimulating hormone (FSH) ,luteinizing hormone (LH) ,androstenedione ,testosterone ,sex hormone-binding globulin (SHBG) and estradiol), oral glucose tolerance test (OGTT) ,baseline and glucose-induced insulin levels ,and transvaginal ultrasonographic and color Doppler analysis (pulsatility index (PI) ,resistance index (RI) and velocity (Vmax) of ovarian stromal flow) were performed in all participants in the early proliferative phase. Endocrine values showed significant differences in PCOS patients compared with PCOS-like women and controls ,while PI and RI indices were significantly higher in controls. PCOS patients were divided into hyperinsulinemic (n = 16) and normoinsulinemic (n = 12). Androstenedione was significantly higher (p < 0.01) in the hyperinsulinemic than in the normoinsulinemic patients and controls ,while SHBG was significantly (p < 0.01) lower in the hyperinsulinemic group. Analysis of color Doppler intraovarian vascularization showed a significantly lower RI and a higher Vmax in the hyperinsulinemic subjects than in the normoinsulinemic PCOS patients and controls. An increased stromal blood flow was observed in the PCOS and PCOS-like patients by transvaginal color Doppler evaluation ,but this technique is not able to differentiate these two similar ovarian patterns. However, hyperinsulinemic PCOS patients had an increased vascularity of the ovarian stroma. A strong correlation between hyperinsulinemia ,hyperandrogenism and low SHBG levels was evidenced ,and a hyperinsulinemia-induced mechanism for ovarian stromal angiogenesis is discussed.
Relations entre les traits fonctionnels des espèces végétales et leurs fonctions de protection contre l'érosion dans les milieux marneux restaurés de montagne

/ Le controle de l'erosion et la retention de sediments comptent parmi les services les plus importants rendus par la vegetation, mais ces fonctions sont de moins en moins bien remplies dans de nombreux milieux. Dans les Alpes du Sud francaises, de vastes affleurements marneux sont soumis a une erosion hydrique intense qui provoque chaque annee la perte de quantites considerables de sol et menace les biens et les personnes en aval des bassins versants. Face a la degradation des milieux, de nombreuses operations de restauration ecologique sont menees afin de retablir les fonctions des ecosystemes et d'assurer un controle durable de l'erosion. Depuis une dizaine d'annees, le role des traits fonctionnels dans le fonctionnement des ecosystemes fait l'objet d'un questionnement important en ecologie et motive de nombreuses recherches. Les traits fonctionnels determinent a la fois la reponse des especes vegetales aux contraintes environnementales et leur effet sur les processus des ecosystemes. Ils permettent egalement la generalisation et la modelisation des resultats pour une plus grande valeur operationnelle. Ce travail de these s'inscrit dans ce contexte. Il a pour objectif de mieux comprendre les relations entre les traits fonctionnels des plantes et, d'une part leur reponse aux contraintes erosives, d'autre part, leur effet de protection contre l'erosion. La resistance des especes vegetales au deracinement et a l'ensevelissement lors d'episodes erosifs intenses ainsi que leurs fonctions de stabilisation des sols et de piegeage des sediments ont ainsi ete etudiees sur des especes herbacees et ligneuses dans leurs premiers stades de developpement. Les resultats obtenus ont permis de mettre en evidence les traits fonctionnels principaux qui influencent la reponse et l'effet des especes a/sur l'erosion. Ainsi, des traits decrivant la morphologie du systeme racinaire, tels que le pourcentage de racines fines, ont pu etre relies a la resistance au deracinement et a la fixation des sols, alors que la forme de croissance et des traits decrivant la morphologie aerienne sont apparus determinants respectivement dans la resistance a l'ensevelissement sous des sediments et leur piegeage. Ce travail contribue a approfondir les connaissances en ecologie de la restauration appliquee aux milieux erodes de montagne et a ameliorer les outils de gestion. En particulier, les resultats peuvent etre utilises pour le diagnostic de la vulnerabilite des milieux a l'erosion ou pour prevoir le succes des operations de restauration.
Lamentation and loss: expressions of caring by contemporary surgical nurses.

AIM This paper is a report of a phenomenological study of caring from the perspective of nurses working on surgical wards. BACKGROUND While care and caring are complex foundational nursing concepts which have received considerable and ongoing attention from theorists, researchers and clinicians, there has been little research into caring on surgical units. METHOD A convenience sample of ten nurses working on surgical units in a public teaching hospital in Canada was interviewed using van Manen's phenomenological approach. Data were collected during 2001 using semi-structured interviews. FINDINGS The major theme of lamentation and loss was identified from the data. Participants revealed a dichotomous tension between what caring should be and what actually occurs. This tension was pervasive and generated lament - an expression of grief and mourning for the loss of caring. The essential structures supporting this theme included lack of time, lack of caring support, tasking, increased acuity, lack of continuity of care, emotional divestment and not caring for each other. Loss and sadness were articulated and participants lamented and grieved about the loss of care in contemporary practice. CONCLUSION The forces and influences described by participants undermined caring in the new practice milieu. If this is a glimpse of the future, then the values of the nursing profession may be under siege. Caring as the central core, the essence or unifying concept of nursing may be subject to marginalization in contemporary practice.
Rapid and accurate measurement of anti‐A/B IgG antibody in ABO‐unmatched living donor liver transplantation by surface plasmon resonance

summary High anti‐blood group A or B (anti‐A/B) immunoglobulin G (IgG) haemagglutination titres are associated with poor graft survival in ABO‐unmatched liver transplantation. We have previously reported that the surface plasmon resonance (SPR) method can be used to measure anti‐A/B IgG levels in the plasma very quickly and quantitatively. The aim of this study was to brush up this SPR method. The anti‐A/B IgG antibodies (Abs) were purified from the plasma of healthy volunteers by affinity chromatography and used to establish standard curves for the SPR and flow cytometry (FCM) methods. The haemagglutination test tube (TT), FCM and SPR methods were then used to measure the changes over time in the anti‐A/B IgG titres of 25 ABO‐unmatched living donor liver transplantation (LDLT) recipients. The standard curve permitted the SPR values for the anti‐A/B IgG titres to be expressed in μg mL−1 units. The SPR measurements of the anti‐A/B IgG levels in the LDLT recipients correlated very well with the FCM values, whereas the TT values correlated poorly with either method. Furthermore, the SPR method accurately detected the effects of plasma exchange. In conclusion, the SPR method is an accurate, time‐ and labour‐saving method for measuring anti‐A/B IgG titres that can be easily standardized.