Design and development of a horizontal contact separated (HCS) test setup for measuring the performance of triboelectric nanogenerator for sustainable energy harvesting applications

Triboelectric nanogenerators (TENGs) can play a pivotal role in harnessing non-utilized reciprocating motion and convert it into electrical energy that can later be stored in a battery or capacitor to power various Internet of Things-based smart electronic and wearable devices. Herein, we designed a cost-effective instrumental test bed focused on investigating the output performance of a horizontal contact separation mode triboelectric nanogenerator by varying the input parameters, such as applied force, motor speed, triboplate separation, and frequency of instrumental setup. The test bed mainly consists of three major parts: (i) application of force, (ii) tapping of TENG sample, and (iii) output parameters measurement. The output performance in terms of open circuit output voltage (VOC), short circuit current (ISC), and power density of polydimethylsiloxane-based TENG was monitored and optimized by varying the input parameters. A low-cost current measuring circuitry using an operational amplifier integrated circuit has been proposed with 92% accuracy. The maximum value of VOC and ISC was observed to be 254 V and 31.8 µA at a motor speed of 600 rpm, the distance between both the plates was 6 mm, the input applied force of 40 N, and the striking frequency of 3 Hz. The maximum power density of 2.1 W/m2 was obtained at an input impedance of 8 kΩ. The durability of the test bed as well as the TENG sample was also measured for 25 h. The degree of uncertainty was measured for VOC, ISC, and applied force and calculated to be 1.62%, 7.45%, and 6.27%, respectively.

Gonadotropin upregulates intraovarian calpains-1 and -2 during ovarian follicular recruitment in the SD rat model

Calpain role has been shown in the cumulus cell-oocyte complexes and, corpus luteum. We investigated the association of calpains-1 and -2 in ovarian folliculogenesis using the Sprague-Dawley (SD) rat model and steroidogenesis in the human granulosa cells (hGCs). We induced PCOS in 42-day-old SD rats by letrozole oral gavage for 21 days. Premature ovarian failure (POF) was induced in 21-day-old SD rats by 4-vinylcyclohexene diepoxide (VCD). Ovulation and ovarian hyperstimulatory (OHS) syndrome were induced by pregnant mare gonadotropin (PMSG) + human chorionic gonadotropin (hCG) treatments in 21 days SD rats, respectively. Steroidogenesis is stimulated in human granulosa cells (hGCs) by forskolin and the response of 17-beta-estradiol (E2) on calpains expression was checked in hGCs. The protein expression by immunoblotting and activity by biochemical assay of calpains-1 and -2 showed an oscillating pattern in the ovarian cycle. PMSG-induced follicular recruitment showed upregulation of calpains-1 and -2, but with no change during ovarian function cessation (POF). Upregulated calpain-2 expression and calpain activity was found in the hCG +PMSG-induced ovulation. Letrozole-induced PCOS showed downregulation of calpain-1, but upregulation of calpain-2. PMSG+hCG-induced OHS led to the upregulation of calpain-1. Letrozole and metformin separately increased the expression level of calpains-1 and -2 in the hGCs during luteinization. In conclusion, the expression levels of calpains -1 and -2 are increased with ovarian follicular recruitment by PMSG and calpain-1 is decreased in the PCOS condition, and letrozole and metformin upregulate the expression of calpains-1 and -2 during luteinization in the hGCs possibly via E2 action.

Health-related quality of life in patients with generalized pustular psoriasis: A systematic literature review

Generalized pustular psoriasis (GPP) is a rare, chronic, neutrophilic inflammatory skin disease characterized by episodes of widespread eruption of sterile, macroscopic pustules that can be accompanied by systemic inflammation and symptoms. A systematic literature review and narrative synthesis were conducted to determine the impact of GPP on patients' health-related quality of life (HRQoL) and patient-reported severity of symptoms and to compare its impact to patients with plaque psoriasis (plaque PsO). Searches were undertaken in Embase, MEDLINE and the Cochrane Library from 1 January 2002 to 15 September 2022. Screening was carried out by two reviewers independently. Outcome measures included generic (e.g. EQ-5D, SF-36) and dermatology-specific (e.g. DLQI) clinical outcome assessments, and other relevant patient-reported outcome measures (PROMs) (e.g. severity of pain measured by a numerical rating scale). Overall, 20 studies were found to be eligible for inclusion, of which seven also had data for plaque PsO. The DLQI was the most frequently reported outcome measure (16 out of 20 studies). When reported, mean DLQI (SD) scores varied from 5.7 (1.2) to 15.8 (9.6) across the studies, indicating a moderate to very large effect on HRQoL; the wide range of scores and large SDs were explained by the small population sizes (n ≤ 12 for all studies except two). Similar ranges and large SDs were also observed for other measures within individual studies. However, in general, people with GPP reported a greater impact of their skin condition on HRQoL, when compared to people with plaque PsO (i.e. higher DLQI scores) and higher severity for itch, pain and fatigue. This systematic review highlighted the need for studies with a larger population size, a better understanding of the impact of cutaneous and extracutaneous symptoms and comorbidities on HRQoL during and between GPP flares, and outcome measures specifically tailored to the unique symptoms and the natural course/history of GPP.

Brain tissue segmentation in neurosurgery: a systematic analysis for quantitative tractography approaches

Diffusion magnetic resonance imaging (dMRI) is a cutting-edge imaging method that provides a macro-scale in vivo map of the white matter pathways in the brain. The measurement of brain microstructure and the enhancement of tractography rely heavily on dMRI tissue segmentation. Anatomical MRI technique (e.g., T1- and T2-weighted imaging) is the most widely used method for segmentation in dMRI. In comparison to anatomical MRI, dMRI suffers from higher image distortions, lower image quality, and making inter-modality registration more difficult. The dMRI tractography study of brain connectivity has become a major part of the neuroimaging landscape in recent years. In this research, we provide a high-level overview of the methods used to segment several brain tissues types, including grey and white matter and cerebrospinal fluid, to enable quantitative studies of structural connectivity in the brain in health and illness. In the first part of our review, we discuss the three main phases in the quantitative analysis of tractography, which are correction, segmentation, and quantification. Methodological possibilities are described for each phase, along with their popularity and potential benefits and drawbacks. After that, we will look at research that used quantitative tractography approaches to examine the white and grey matter of the brain, with an emphasis on neurodevelopment, ageing, neurological illnesses, mental disorders, and neurosurgery as possible applications. Even though there have been substantial advancements in methodological technology and the spectrum of applications, there is still no consensus regarding the "optimal" approach in the quantitative analysis of tractography. As a result, researchers should tread carefully when interpreting the findings of quantitative analysis of tractography.

Prevalence of maternal depression and anxiety symptoms and associations with child mental health outcomes in rural Nepal

OBJECTIVES

This study describes the prevalence, associated factors and child mental health outcomes related to symptoms of maternal depression and anxiety within 5 years after childbirth in a rural district in Nepal. This association is not well-understood in rural, community-based settings in low- and middle-income countries (LMIC).

METHODS

A sample of 347 women with children under 5 years was recruited in September 2019 for a cross-sectional study in the rural Saptari district in Nepal. Multivariable logistic regression was used to investigate the association between maternal depressive or anxiety symptoms and children's experience and impact of emotional and behavioural difficulties.

RESULTS

In total, 144 women (41.5%) had moderate or severe depression symptoms and 118 (34%) had anxiety symptoms. Mothers with a lower income were more likely to have anxiety symptoms than the highest income group (OR: 1.8, 95% CI: 1.1-3.0). An association existed between maternal depressive symptoms and the impact of emotional or behavioural difficulties in children (OR: 2.44, 95% CI: 1.02-5.84). In contrast, there was no association between maternal anxiety and child outcomes.

CONCLUSIONS

Our findings suggest that the prevalence of probable maternal anxiety and depression symptoms was relatively high in this rural, low-resourced and community-based setting in Nepal. Maternal depressive symptoms were associated with the degree of impact on children's mental health post-infancy, emphasising the importance of improving maternal mental health in the early years of a child's life.

Naringenin improves ovarian health by reducing the serum androgen and eliminating follicular cysts in letrozole-induced polycystic ovary syndrome in the Sprague Dawley rats

Polycystic ovary syndrome (PCOS) is most common in women of reproductive age, giving rise to androgen excess and anovulation, leading to infertility and non-reproductive complications. We explored the ameliorating effect of naringenin in PCOS using the Sprague Dawley (SD) rat model and human granulosa cells. Letrozole-induced PCOS rats were given either naringenin (50 mg/kg/day) alone or in combination with metformin (300 mg/kg/day), followed by the estrous cycle, hormonal analysis, and glucose sensitivity test. To evaluate the effect of naringenin on granulosa cell (hGC) steroidogenesis, we treated cells with naringenin (2.5 μM) alone or in combination with metformin (1 mM) in the presence of forskolin (10 μM). To determine the steroidogenesis of CYP-17A1, -19A1, and 3βHSD2, the protein expression levels were examined. Treatment with naringenin in the PCOS animal groups increased ovulation potential and decreased cystic follicles and levels of androgens. The expression levels of CYP-17A1, -19A1, and 3βHSD2, were seen restored in the ovary of PCOS SD rats' model and in the human ovarian cells in response to the naringenin. We found an increased expression level of phosphorylated-AKT in the ovary and hGCs by naringenin. Naringenin improves ovulation and suppress androgens and cystic follicles, involving AKT activation.

Brain Disorders: Impact of Mild SARS-CoV-2 May Shrink Several Parts of the Brain

Coronavirus (COVID-19) is a highly infectious respiratory infection discovered in Wuhan, China, in December 2019. As a result of the pandemic, several individuals have experienced life-threatening diseases, the loss of loved ones, lockdowns, isolation, an increase in unemployment, and household conflict. Moreover, COVID-19 may cause direct brain injury via encephalopathy. The long-term impacts of this virus on mental health and brain function need to be analysed by researchers in the coming years. This article aims to describe the prolonged neurological clinical consequences related to brain changes in people with mild COVID-19 infection. When compared to a control group, people those who tested positive for COVID-19 had more brain shrinkage, grey matter shrinkage, and tissue damage. The damage occurs predominantly in areas of the brain that are associated with odour, ambiguity, strokes, reduced attention, headaches, sensory abnormalities, depression, and mental abilities for few months after the first infection. Therefore, in patients after a severe clinical condition of COVID-19, a deepening of persistent neurological signs is necessary.

PKC-βII is downregulated in the premature ovarian failure SD rat model

We investigated the role of protein kinase c (PKC) -α and -β during the ovarian follicular dynamics using estrous cycle, gonadotropin-induced ovulation, and antral follicle culture, 4-vinylcyclohexene diepoxide (VCD)-induced premature ovarian failure (POF) in the SD rat models. We found the higher activity of PKC during the proestrus stage along with expression of PKC-α during the estrus and metestrus stages of the estrous cycle while PKC-β expression was increased during the diestrus, proestrus, and estrus stages. In response to pregnant mare gonadotropin (PMSG)-induced follicular recruitment and ovulation, the phosphorylated (Thr-642) PKC-β was increased. PKC activity inhibition by hispidin during the proestrus stage resulted in decreased antral follicles and corpus luteum. Treatment with hispidin resulted in the downregulation of granulosa cell (GC) biomarker, follicle stimulating hormone receptor (FSHR) expression in the cultured pre-antral follicle. During the forskolin-induced luteinization of human granulosa cells, the expression level of PKC-α and β (I and II) was decreased. In the POF condition, the activity of total PKC and the expression levels of PKC-α and β (I and II) were increased. Immunostaining depicted ubiquitous expression of PKC-α in the ovary during the estrous cycle and POF conditions. Taken together, we conclude the association of PKC-α and -β (I and II) during ovarian follicular dynamics where the expression level of PKC-α is increased, but the expression level of PKC-β (I and II) is suppressed in the POF condition in the SD rat model.

A Ketogenic Diet is Effective in Improving Insulin Sensitivity in Individuals with Type 2 Diabetes

OBJECTIVE

This systematic review looked at different clinical trials that explored the beneficial effect of a ketogenic diet on insulin sensitivity in Type 2 Diabetics, both with and without exercise. It was hypothesized that a ketogenic diet is effective in improving insulin sensitivity in individuals with Type 2 Diabetes, with the greatest effect resulting from a ketogenic diet paired with exercise.

METHODS

The databases used when searching were the Directory of Open Access Journals and PubMed for randomized control trials, non-randomized control trials, and prospective longitudinal studies. Results were summarized in an evidence table found in the Appendix. Studies were not limited by study type, age of study participants, gender, ethnicity, language, journal in which the studies were published, or geographic location. One study utilized mouse models. Statistical analysis was not performed.

RESULTS

Twelve trials were studied. Three trials studied the role of exercise and a ketogenic diet in the treatment of Type 2 Diabetes. Five trials studied a ketogenic diet compared to another diet in the treatment of Type 2 Diabetes. Two trials studied a ketogenic diet alone in the treatment of Type 2 Diabetes. One trial studied a ketogenic diet in those with pre-diabetes. One trial studied a ketogenic diet in those with pre-diabetes and those diagnosed with Type 2 Diabetes. Every trial utilizing a ketogenic diet showed marked improvement in glycemic control among participants in support of the hypothesis. One study noted that while a ketogenic diet greatly improved glycemic control, it created problems with lipid metabolism and the liver. When pairing a ketogenic diet with exercise, hepatic steatosis was avoided. Eleven studies used adult participants, one used mouse models. One study was a prospective longitudinal study, nine randomized control trials, one nonrandomized control trial, and one observational cohort study.

CONCLUSIONS

The studies provide encouraging results. A ketogenic diet consistently demonstrates improved glycemic control in Type 2 Diabetics, and in those at risk of Type 2 Diabetes. However, the studies are limited in their lack of exploration of the effects of a long-term ketogenic diet on the liver, with only one study including this data. Randomized trials looking at the effect of a ketogenic diet on the liver are needed. In addition, there were very few studies found when researching that paired a ketogenic diet with exercise to study both the effect on glycemic control, as well as avoiding potential hepatic steatosis.

Differential Physio-Biochemical and Metabolic Responses of Peanut (Arachis hypogaea L.) under Multiple Abiotic Stress Conditions

The frequency and severity of extreme climatic conditions such as drought, salinity, cold, and heat are increasing due to climate change. Moreover, in the field, plants are affected by multiple abiotic stresses simultaneously or sequentially. Thus, it is imperative to compare the effects of stress combinations on crop plants relative to individual stresses. This study investigated the differential regulation of physio-biochemical and metabolomics parameters in peanut (Arachis hypogaea L.) under individual (salt, drought, cold, and heat) and combined stress treatments using multivariate correlation analysis. The results showed that combined heat, salt, and drought stress compounds the stress effect of individual stresses. Combined stresses that included heat had the highest electrolyte leakage and lowest relative water content. Lipid peroxidation and chlorophyll contents did not significantly change under combined stresses. Biochemical parameters, such as free amino acids, polyphenol, starch, and sugars, significantly changed under combined stresses compared to individual stresses. Free amino acids increased under combined stresses that included heat; starch, sugars, and polyphenols increased under combined stresses that included drought; proline concentration increased under combined stresses that included salt. Metabolomics data that were obtained under different individual and combined stresses can be used to identify molecular phenotypes that are involved in the acclimation response of plants under changing abiotic stress conditions. Peanut metabolomics identified 160 metabolites, including amino acids, sugars, sugar alcohols, organic acids, fatty acids, sugar acids, and other organic compounds. Pathway enrichment analysis revealed that abiotic stresses significantly affected amino acid, amino sugar, and sugar metabolism. The stress treatments affected the metabolites that were associated with the tricarboxylic acid (TCA) and urea cycles and associated amino acid biosynthesis pathway intermediates. Principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and heatmap analysis identified potential marker metabolites (pinitol, malic acid, and xylopyranose) that were associated with abiotic stress combinations, which could be used in breeding efforts to develop peanut cultivars that are resilient to climate change. The study will also facilitate researchers to explore different stress indicators to identify resistant cultivars for future crop improvement programs.

Introgression of SbERD4 Gene Encodes an Early-Responsive Dehydration-Stress Protein That Confers Tolerance against Different Types of Abiotic Stresses in Transgenic Tobacco

Salicornia brachiata is an extreme halophyte that commonly grows on marsh conditions and is also considered a promising resource for drought and salt-responsive genes. To unveil a glimpse of stress endurance by plants, it is of the utmost importance to develop an understanding of stress tolerance mechanisms. 'Early Responsive to Dehydration' (ERD) genes are defined as a group of genes involved in stress tolerance and the development of plants. To increase this understanding, parallel to this expedited thought, a novel SbERD4 gene was cloned from S. brachiata, characterized, and functionally validated in the model plant tobacco. The study showed that SbERD4 is a plasma-membrane bound protein, and its overexpression in tobacco plants improved salinity and osmotic stress tolerance. Transgenic plants showed high relative water, chlorophylls, sugars, starch, polyphenols, proline, free amino acids, and low electrolyte leakage and H2O2 content compared to control plants (wild type and vector control) under different abiotic stress conditions. Furthermore, the transcript expression of antioxidant enzyme encoding genes NtCAT, NtSOD, NtGR, and NtAPX showed higher expression in transgenic compared to wild-type and vector controls under varying stress conditions. Overall, the overexpression of a novel early responsive to dehydration stress protein 4-encoding gene (SbERD4) enhanced the tolerance of the plant against multiple abiotic stresses. In conclusion, the overexpression of the SbERD4 gene mitigates plant physiology by enduring stress tolerance and might be considered as a promising key gene for engineering salinity and drought stress tolerance in crops.

miR-149-PARP-2 Signaling Regulates E-cadherin and N-cadherin Expression in the Murine Model of Endometrium Receptivity

Cadherins play an essential role in the attachment of the blastocyst to the endometrium, a process known as endometrial receptivity. Loss of E-cadherin expression is essential during the process, while the expression level of the other cadherin, N-cadherin, has been reported to be altered in cases of infertility. Both E-cadherin and N-cadherin can be regulated by members of the PARP family. Specifically, PARP-2, which is under the epigenetic control of miR-149, has been observed to promote E-cadherin expression in other human cells. We investigated the roles of E-cadherin and N-cadherin in endometrial receptivity using mouse models for normal endometrial receptivity, pseudopregnancy, and LPS-induced endometrial receptivity failure. E-cadherin and phosphorylated E-cadherin were predominantly expressed during pre-receptive stages as well as in the implantation site of the receptive stage, which were observed reduced during the later stages of implantation in both implantation and non-implantation regions, while N-cadherin was detected only at pre-receptive stages. E-cadherin and N-cadherin were also seen in the uterus during pseudopregnancy, showing a downregulation trend during receptive and post-receptive stages. LPS-induced failed endometrial receptivity showed upregulation of E-cadherin and downregulation of N-cadherin. The E-cadherin expression promoter, GSK-3, was lost and its suppressor, SLUG was upregulated during normal course of endometrial receptivity in mouse model, while GSK-3 was increased during LPS-induced failed embryo implantation. In an in vitro model of embryo implantation, E-cadherin expression is promoted by PARP-2 and regulated by miR-149 epigenetically in human endometrium epithelial cells. In conclusion, E-cadherin is predominantly expressed during pre-receptive stage and promoted by PARP-2, which is regulated by miR-149 in the endometrial epithelial cells.

Introgression of a novel cold and drought regulatory-protein encoding CORA-like gene, SbCDR, induced osmotic tolerance in transgenic tobacco

A potent cold and drought regulatory-protein encoding gene, SbCDR was cloned from an extreme halophyte Salicornia brachiata. In vitro localisation study, performed with SbCDR::RFP gene-construct revealed that SbCDR is a membrane protein. Overexpression of the SbCDR gene in tobacco plants confirmed tolerance against major environmental constraints such as salinity, drought and cold, as evidenced by improved chlorophyll contents, plant morphology, plant biomass, root length, shoot length and seed germination efficiency. Transgenic lines also exhibited high accumulation of proline, total sugar, reducing sugar, free amino acid and polyphenol, besides the low level of malondialdehyde (MDA) contents. SbCDR transgenic lines showed better relative water contents, membrane stability index and osmotic water potential. Furthermore, higher expression of ROS scavenging genes was observed in transgenic lines under stress. Moreover, microarray analysis revealed that several host genes were upregulated and downregulated under drought and salt stress conditions in SbCDR transgenic line compared with control (WT) plants. The results demonstrated that the overexpression of the halophytic SbCDR gene has intense effects on the abiotic stress tolerance of transgenic tobacco plants. However, the exact mode of action of SbCDR in multiple abiotic stress tolerance of plants is yet to be unveiled. It is believed that the precise role of SbCDR gene will provide additional information to comprehend the abiotic stress tolerance mechanism. Furthermore, it will appear as a promising candidate gene for improving stress tolerance in different crop plants for sustainable agriculture and crop productivity.

miRNA-149 targets PARP-2 in endometrial epithelial and stromal cells to regulate the trophoblast attachment process

Embryo implantation is a highly complex process involving many regulatory factors, including several micro RNAs (miRNAs/miRs). One miRNA present in the stromal cells of normal endometrium is miR-149, which targets poly (ADP-ribose) polymerase 2 (PARP-2), a gene involved in endometrial receptivity for trophoblast implantation. However, the precise role of miR-149 in the endometrial receptivity during blastocyst implantation is still unknown. We studied miR-149-dependent PARP-2 regulation during trophoblast attachment to endometrial epithelial cells. Using FISH, we found that miR-149 is expressed in mouse endometrial epithelial and stromal cells at implantation and inter-implantation sites. Endometrial receptivity for embryo implantation and attachment is inhibited by the upregulation of miR-149 in the endometrium. Our RT-PCR analysis revealed downregulation of miR-149 in the implantation region of the uterus during the receptive stage (Day 5, 0500 h, p.c.) in the mouse. Under in-vitro conditions, miR-149 overexpression in human endometrial epithelial cells (hEECs) abrogated the human trophoblastic cells spheroid and mouse blastocyst attachment. Subsequently, miR-149 also regulates transformed human endometrial stromal cell (T-hESCs) decidualization by downregulating PARP-2 and upregulating caspase-8 proteins. Overexpression of miR-149 in hEECs and downregulated PARP-2 protein expression, reconfirming that PARP-2 is a downstream target of miR-149 in endometrial cells as well. miR-149 is also able to alter the expression of caspase-8, another PARP-2 regulator. In conclusion, our data indicate that miR-149 is one of the regulators of endometrial receptivity and decidualization for trophoblast implantation, and it exerts the effects by acting on the downstream targets PARP-2 and caspase-8.

Poly(ADP-ribose) polymerase-2 is essential for endometrial receptivity and blastocyst implantation, and regulated by caspase-8

Embryo implantation is a very complex process and several factors play important roles. Using a mouse model, we investigated the functions of PARP-2 and caspase-8 during endometrial receptivity for blastocyst implantation. We found that PARP-2 was upregulated at the receptive stage's implantation region and predominantly expressed in the endometrial stromal region, but downregulated during pregnancy failure and pseudopregnancy. To reinforce the necessity of PARP-2 for embryo implantation, we pharmacologically inhibited PARP-2 'before' & 'after' embryo arrival and observed a reduction in blastocyst implantation. Conversely, elevated caspase-8 expression and activity during pseudopregnancy, delayed implantation, and embryo implantation failure conditions and decreased levels in the decidualization exhibited an inverse pattern with PARP-2, suggesting caspase-8 as a negative regulator for embryo implantation. In vitro caspase-8 downregulates the PARP-2 activity in the mouse endometrial epithelial and stromal cells. These data suggest that PARP-2 and its negative regulation by caspase-8 constitute a crucial step in embryo implantation.

Exploring the effectiveness of incorporating carbon nanotubes into bioengineered scaffolds to improve cardiomyocyte function

INTRODUCTION

Carbon nanotubes are effective in improving scaffolds to enhance cardiomyocyte function and hold great promise in the field of cardiac tissue engineering.

AREAS COVERED

A PubMed and Google Scholar search was performed to find relevant literature. 18 total studies were used as primary literature. The literature revealed that the incorporation of carbon nanotube into biocompatible scaffolds that mimic myocardial extracellular matrix enhanced the ability to promote cell functions by improving physical profiles of scaffolds. Several studies showed improved scaffold conductance, mechanical strength, improvements in cell properties such as viability, and beating behavior of cells grown on carbon nanotube incorporated scaffolds. Carbon nanotubes present a unique opportunity in the world of tissue engineering through reparation and regeneration of the myocardium, an otherwise irreparable tissue.

EXPERT OPINION

The high burden of cardiovascular disease has prompted research into cardiac tissue engineering applications. Carbon-nanotube incorporation into extracellular matrix-mimicking-scaffolds has shown to improve cardiomyocyte conductivity, viability, mechanical strength, beating behavior, and have protected them from damage to a certain degree. These are promising findings that have the potential of becoming the focus of future cardiac tissue engineering research.

Impact of HfO₂ as a Passivation Layer in the Solar Cell Efficiency Enhancement in Passivated Emitter Rear Cell Type

We report the simulation of high-efficiency c-silicon Passivated Emitter Rear Contact (PERC) type solar cell structure with rear side passivated with HfO₂ as a passivating material. Variation in the half length of pyramid has been carried out to investigate its effect on the solar cell electrical characteristics such as fill factor (FF), open circuit voltage (V_oc) and efficiency. Aluminum back Surface Field (Al-BSF) and PERC type solar cell with Al₂O₃ passivation layer structures were also modeled for comparison. Effect of variation in passivation layer (HfO₂) thickness (10 and 15 nm) and permittivity (k = 14 and 25) on the solar cell electrical characteristics has been investigated. Result shows the efficiency improvement in the PERC solar cell with HfO₂ passivation layer by 0.5941% and 0.983% as compared to the Al-BSF and PERC with Al₂O₃ passivation layer at 8 μm pyramid half length. Increased series resistance and reduced FF has been observed with the incorporation of passivation layer at the solar cell structure. Negligible effect of passivation layer thickness has been observed on the solar cell electrical parameters whereas the permittivity value does have significant effect.

Effects of Cold Stimulation Induced Pain on Cardiopulmonary Parameters: A Gender Based Study

Background Cold pressor induced pain elicits sympathetic responses which can be monitored by measuring blood pressure, heart rate and respiratory rate after exposure to the cold stress. Objective This study was done to evaluate gender difference in acute pain induced by cold pressor test on blood pressure, heart rate and respiratory rate of healthy individuals. Method Our study was cross sectional study with the sample size of 40 including 20 male and 20 female undergraduates. Acute pain was induced by immersion of hand in cold water at 4o C. Changes in blood pressure, heart rate and respiratory rate were recorded by the digital sphygmomanometer and AD Instruments (Model: ML856, Serial: T26-4025) and analysis was done by Lab Chart 7 Pro v 7.3.3 respectively. Acute pain parameter like pain threshold was also recorded. Statistical analysis was done by using Paired "t" test and non-parametric test. Result The present study enrolled 40 participants, aged between 18 - 24 years, and body mass index from 15.78 - 36.06 kg/m2 . The respiratory rate was increased in both males (17.30±3.19 to 19.0±3.21, P=0.01) and females (18.60±1.98 to 19.90±2.82, P= 0.01) however significant increase in heart rate was only found in females (77.80±8.07 to 80.70±7.80, P=0.03) after cold pressor test. The systolic as well as diastolic blood pressure did not increase significantly after cold pressor test. The pain thresholds ranged from 25.2 to 105.8 seconds (61.60±23.26, male Vs. 52.69±18.49, female, p = 0.188). Conclusion Our findings point towards autonomic adjustments suggesting more of sympathetic over activity immediately after cold pressor test.

Skin Conductance and RR Interval for Regulated Discrete Physiological Stimuli: A Two Prong Strategy to Detect Sympathetic Activation

Background Several studies have found skin conductance a good indicator for detection of sympathetic response. But, valid and reliable tool for detection of sympathetic outflow in health and disease is still a quest. Thereby, comparison of superficial and, at core sympathetic effluence induced by deliberately supplied discrete external stimuli has been attempted in this study. Objective To assess the degree of sympathetic outflow for discrete cognitive and physical stimuli through perturbations in skin conductance and variations in heart rate in healthy adults. Method Quantitative and cross-sectional study was performed in 104 healthy subjects following random sampling method. Induction of sympathetic activity was realized by providing separate time bound cognitive exercises intervened with change in posture. Recordings to detect sympathetic responses at rest and, for supplied stimuli were made by electrocardiogram and galvanic skin response. Result Cognitive performance and postural change shifts baseline effluence and increases the sympathetic outflow significantly (p=0.000). There occurs no detectable rise in sympathetic effluence at the core (p=0.362) but, eventuate significantly appreciable sympathetic outflow to sweat glands in skin (p=0.000), when compared cognitive versus physical stimuli. Conclusion Sympathetic outflow induced by cognitive challenge and physical change in posture is readily assessable through sympathetic skin response yet core sympathetic effluence for latter stimuli is steady and unwavering. Differential effluence for sympathetic response called upon by discrete stimuli is operational for maintenance of steady state in healthy subjects.

Medical students' perceptions of their learning environment during clinical years at Chitwan Medical College in Nepal

BACKGROUND

The educational environment of an institution affects learning and has a significant role in determining students' academic achievement. The objective of the study was to determine the undergraduate medical students' perception about educational environment in clinical years of study utilizing Dundee Ready Education Environment Measure (DREEM) questionnaire.

METHODS

A descriptive cross-sectional questionnaire-based study was conducted among fourth and fifth-year medical students toward the end of their 2016 academic year in Chitwan Medical College, Bharatpur, Nepal. The 50-item DREEM questionnaire was used to collect the data. The items were scored based on a 5-point Likert scale. The data were analyzed using SPSS version 20. Scores obtained were expressed as mean±SD.

RESULTS

The mean total DREEM score was 122/200. The mean score for Students' Perceptions of Learning, Students' Perceptions of Teachers, Students' Academic Self-Perceptions, Students' Perceptions of Atmosphere, and Students' Social Self-Perceptions were 29.8/48, 25.9/44, 20.3/32, 28.6/48, and 17.27/28, respectively. This shows the environment for learning was satisfactory. There were nine problem areas with a mean score of ≤2. There was no significant difference observed in educational environment subscales scores according to enrollment year, gender, or funding source for education.

CONCLUSION

The overall student's perception of the educational environment was satisfactory. Nevertheless, the study revealed some problematic areas in the learning environment which require remedial measures to make the environment more conducive for learning to satisfy the students and achieve a far better outcome.

Recent advances in Staphylococcus aureus infection: focus on vaccine development

Staphylococcus aureus normally colonizes the nasal cavity and pharynx. After breaching the normal habitat, the organism is able to cause a number of infections at any site of the body. The development of antibiotic resistance has created a global challenge for treating infections. Therefore, protection by vaccines may provide valuable measures. Currently, several vaccine candidates have been prepared which are either in preclinical phase or in early clinical phase, whereas several candidates have failed to show a protective efficacy in human subjects. Approaches have also been made in the development of monoclonal or polyclonal antibodies for passive immunization to protect from S. aureus infections. Therefore, in this review we have summarized the findings of recently published scientific literature to make a concise report.

Galvanic Skin Response as a Simple Physiology Lab Teaching Tool- An Alternative Indicator of Sympathetic Arousal

Background Sympathetic arousal response due to rewarding emotion may not be considered threat to the well-being but such arousal response evoked by fear or punishment can be stressful. When such changes are recorded in lab as biological signals, induced with appropriate stimulus, the observed response may serve as a good indicator of homeostatic alteration. In this study, skin conductance was utilized to record sympathetic response for cognitive load, by application of simple subtraction task. Objective To detect sympathetic arousal by utilization of galvanic skin response during mental arithmetic task. Method Total of eighty two subjects, forty two female and forty male participated in the study. Twenty two subjects were provided mental task to record skin conductance. In sixty subjects, galvanic skin response, pulse rate, respiratory rate and temperature were recorded by appropriate transducers to obtain baseline and task response to detect differential recordings. Subjects performed the mental exercise of arithmetic task (MAT) with transducer placed in upper limbs. Mean of averages for respective variables were statistically calculated from obtained recordings. Result For measured galvanic skin response, 57 subjects showed increased skin conductance (rise in amplitude) whereas, 25 subjects had no rise in amplitude ("A peak") while performing the mental arithmetic task, when compared to control recording. However, in 20 subjects, pulse rate and respiratory rate showed significant rise though, the change in the skin conductance was not significant. Conclusion Galvanic skin response is useful for demonstration of sympathetic activation induced by simple mental subtraction task, and can be utilized along with vital parameters mentioned in this study to discuss in vivo variation that exist as differential for core and superficial sympathetic outflow among individuals.

CD44 targeting hyaluronic acid coated lapatinib nanocrystals foster the efficacy against triple-negative breast cancer

Lapatinib (LPT) is an orally administered drug for the treatment of metastatic breast cancer. For expanding its therapeutic horizon, we have prepared its nanocrystals (LPT-NCs) that were subsequently coated with hyaluronic acid (HA) to produce LPT-HA-NCs. The detailed in-vitro and in-vivo investigation of LPT-HA-NCs showed the superior anticancer activity due to active targeting to CD44 receptors than the counterparts LPT-NCs and free LPT. In the triple negative 4T1 cells induced breast tumor bearing female Balb/C mice; LPT-HA-NCs treatment caused significant retardation of tumor growth and overall increase in animal survival probability because of their higher tumor localization, increased residence time. Our findings clearly suggest that HA coated LPT-NCs formulation enhances the activity of LPT against triple negative breast cancer. It exhibited magnificent therapeutic outcome at low dose thus presenting a strategy to reduce dose administrations and minimize dose related toxicity.

Integrin beta8 (ITGB8) activates VAV-RAC1 signaling via FAK in the acquisition of endometrial epithelial cell receptivity for blastocyst implantation

Integrin beta8 (ITGB8) is involved in the endometrial receptivity. The blastocyst first interacts with the luminal endometrial epithelial cells during its implantation; therefore, we have investigated the signaling of ITGB8 via FAK and VAV-RAC1 in the endometrial epithelial cells. Integrin beta8 was found elevated in epithelial cells at late-pre-receptive (day4, 1600 h) and receptive (day5, 0500 h) stages of endometrial receptivity period in the mouse. Integrins downstream molecule FAK has demonstrated an increased expression and phosphorylation (Y397) in the endometrium as well as in the isolated endometrial epithelial cells during receptive and post-receptive stages. Integrin beta8 can functionally interact with FAK, VAV and RAC1 as the levels of phosphorylated-FAK, and VAV along with the RAC-GTP form was reduced after ITGB8 knockdown in the endometrial epithelial cells and uterus. Further, VAV and RAC1 were seen poorly active in the absence of FAK activity, suggesting a crosstalk of ITGB8 and FAK for VAV and RAC1 activation in the endometrial epithelial cells. Silencing of ITGB8 expression and inhibition of FAK activity in the Ishikawa cells rendered poor attachment of JAr spheroids. In conclusion, ITGB8 activates VAV-RAC1 signaling axis via FAK to facilitate the endometrial epithelial cell receptivity for the attachment of blastocyst.

Treatment of Prosthetic Valve Thrombosis with Bolus Dose Tenecteplase: An Experience from a Developing Country

BACKGROUND AND AIM OF THE STUDY

Prosthetic valve thrombosis (PVT) in metallic prosthetic cardiac valves is not an uncommon condition, and has high mortality and morbidity. Although surgery is the traditional choice for PVT therapy, thrombolysis with newer agents has achieved good success rates. Many studies described in the western literature have used tissue plasminogen activators, while studies from developing countries have been largely based on the use of streptokinase and urokinase. Data regarding the use of newer agents such as tenecteplase are scant. Hence, the study aim was to evaluate the safety and efficacy of tenecteplase in left-sided PVT.

METHODS AND RESULTS

Between 2013 and 2016, a total of 18 patients with PVT was treated with a 40 mg bolus dose of tenecteplase. Significantly, one patient was a pregnant lady in whom a lower dose (25 mg) was successfully and safely used. Thrombolysis was followed by enoxaparin and oral anticoagulation in patients, all of whom had complete lysis of thrombus and clinical improvement.

CONCLUSIONS

Tenecteplase is an effective and excellent therapeutic agent for PVT, with a good safety margin. Its safe use in pregnancy points to a possible optional therapy, but this requires confirmation.

Potentially inappropriate prescribing in elderly population: A study in medicine out-patient department

Background & Objectives: Older individuals often suffer from multiple systemic diseases and are particularly more vulnerable to potentially inappropriate medicine prescribing. Inappropriate medication can cause serious medical problem for the elderly. The study was conducted with objectives to determine the prevalence of potentially inappropriate medicine (PIM) prescribing in older Nepalese patients in a medicine outpatient department.Materials & Methods: A prospective observational analysis of drugs prescribed in medicine out-patient department (OPD) of a tertiary hospital of central Nepal was conducted during November 2012 to October 2013 among 869 older adults aged 65 years and above. The use of potentially inappropriate medications (PIM) in elderly patients was analysed using Beer’s Criteria updated to 2013. Results: In the 869 patients included, the average number of drugs prescribed per prescription was 5.56. The most commonly used drugs were atenolol (24.3%), amlodipine (23.16%), paracetamol (17.6%), salbutamol (15.72%) and vitamin B complex (13.26%). The total number of medications prescribed was 4833. At least one instance of PIM was experienced by approximately 26.3% of patients when evaluated using the Beers criteria. Conclusion: Potentially inappropriate medications are highly prevalent among older patients attending medical OPD and are associated with number of medications prescribed. Further research is warranted to study the impact of PIMs towards health related outcomes in these elderly.

RHOG-DOCK1-RAC1 Signaling Axis Is Perturbed in DHEA-Induced Polycystic Ovary in Rat Model

The function of RHOG, a RAC1 activator, was explored in the ovary during ovarian follicular development and pathological conditions. With the help of immunoblotting and immunolocalization, we determined the expression and localization of RHOG in normal (estrous cycle) and polycystic ovaries using Sprague Dawley (SD) rat model. Employing polymerase chain reaction and flow cytometry, we analyzed the transcript and expression levels of downstream molecules of RHOG, DOCK1, and RAC1 in the polycystic ovarian syndrome (PCOS) ovary along with normal antral follicular theca and granulosa cells after dehydroepiandrosterone (DHEA) supplementation. The effect of RHOG knockdown on DOCK1, VAV, and RAC1 expression was evaluated in the human ovarian cells (SKOV3), theca cells, and granulosa cells from SD rats with the help of flow cytometry. Oocyte at secondary follicles along with stromal cells showed optimal expression of RHOG. Immunoblotting of RHOG revealed its maximum expression at diestrus and proestrus, which was downregulated at estrus stage. Mild immunostaining of RHOG was also present in the theca and granulosa cells of the secondary and antral follicles. Polycystic ovary exhibited weak immunostaining for RHOG and that was corroborated by immunoblotting-based investigations. RHOG effectors DOCK1 and ELMO1 were found reduced in the ovary in PCOS condition/DHEA. RHOG silencing reduced the expression of DOCK1 and RAC1 in the theca and granulosa cells from SD rat antral follicles and that was mirrored in the human ovarian cells. Collectively, RHOG can mediate signaling through downstream effectors DOCK1 and RAC1 during ovarian follicular development (theca and granulosa cells and oocyte), but DHEA downregulated them in the PCOS ovary.

Varicella myopericarditis mimicking acute myocardial infarction with ARDS – A rare association in an immunocompetent young adult

Primary varicella infection in an immunocompetent young adult is very rare, but it has a high mortality rate due to serious complications. We report a rare association of varicella pneumonia presenting in acute respiratory distress with mild chest pain, however with electrocardiographic and biochemical markers suggestive of acute ST elevation myocardial infarction. Coronary angiography was done to exclude infarction, serum antibody titers confirmed varicella, acyclovir was started, and ARDS was successfully treated with steroid pulse therapy and mechanical ventilator support. Early administration of antivirals and aggressive management of ARDS were thought to be necessary to overcome the potential life-threatening complications of varicella infection in adults. This case illustrates that not every MI is really MI.

Facebook use and its effects on the life of health science students in a private medical college of Nepal

BACKGROUND

Facebook, a popular social networking site, has been used by people of different ages and professions for various purposes. Its use in the field of medical education is increasing dramatically. At the same time, the pros and cons of facebook use among the health science students has attracted the attention of educators. The data regarding its use and the effect on the life of Nepalese health science students has not yet been documented. Therefore, this study is carried out to evaluate the effect of facebook use on social interactions, behaviour, academics, and the health of students in a medical college of Nepal.

RESULTS

A cross-sectional descriptive study conducted among medical, dental, nursing and allied health science students using self-administered questionnaire. The study showed that 98.2 % of participants were facebook users. Among 452 respondents, 224 and 228 were male and female respectively, with a mean age of 20.2 ± 1.2 years. The main reason for using facebook was to remain in contact with family and friend (32 %), while its use for the academic purpose was only 5 %. However, 80.8 % of students acknowledged ease in acquiring academic materials from others, through facebook. One-fourth of the students acknowledged that they are using facebook late at night on a regular basis, while surprisingly 4.2 % of the students admitted accessing facebook during the classroom lectures. Almost two-third of the users, further admitted that facebook has had a negative impact on their studies. Burning eyes (21 %), disturbed sleep (19 %), and headache (16 %) were the most common adverse health effects reported by the facebook users. Many students (71.4 %) tried and most of them (68.7 %) succeeded, in reducing time spent on facebook, to allow for increased time devoted to their studies.

CONCLUSION

The widespread use of facebook among the health science students, was found to have both positive and negative effects on their academics, social life, and health.

Endoglin (CD105) coordinates the process of endometrial receptivity for embryo implantation

Endoglin is a TGF-β receptor that is expressed in uterine endothelial and stromal cells in addition to trophoblast expression. However, the functional importance of endoglin in the embryo implantation process is not clear. We observed endoglin expression in the endometrium throughout the stages of its receptivity; however, its expression was enhanced during the receptive stage. Endoglin expression was predominant in epithelial cells of the lumen and glands, but showed a milder expression in stromal cells. Endoglin expression was initially observed in the primary decidual zone and later extended to the secondary decidua zone. Knockdown of endoglin via siRNA reduced the implantation sites along with the blastocyst numbers. Mouse blastocyst with endoglin-silenced endometrial epithelial cells (human and mouse origin) showed poor trophoblast outgrowth, which suggests an essential role for endoglin during endometrial receptivity. In conclusion, our findings reveal the association of endoglin with endometrial receptivity, which is important for embryo attachment.

Is MTHFR 677 C>T Polymorphism Clinically Important in Polycystic Ovarian Syndrome (PCOS)? A Case-Control Study, Meta-Analysis and Trial Sequential Analysis

BACKGROUND

Optimum efficiency of the folate pathway is considered essential for adequate ovarian function. 677 C>T substitution in the 5, 10-methylene tertrahydrofolatereductase (MTHFR) gene compromises activity of the MTHFR enzyme by about 50%. The significance of correlation between 677C>T substitution and PCOS remains dubious due to the low power of published studies.

METHODS AND RESULTS

We analyzed MTHFR 677 C>T site in ethnically two different PCOS case-control groups (total 261 cases and 256 controls) from India. The data analysis revealed a lack of association between this polymorphism and PCOS [OR = 1.11 (95%CI = 0.71-1.72), P = 0.66]. Group-wise analysis on the basis of ethnicity also revealed no association in any of the ethnic groups [Indo-Europeans, P = 1; Dravidians, P = 0.70]. Homocysteine levels did not differ significantly between cases (15.51 μmol/L, SD = 2.89) and controls (15.89 μmol/L, SD = 2.23). We also undertook a meta-analysis on 960 cases and 1028 controls, which suggested a significant association of the substitution with PCOS in the dominant model of analysis (OR = 1.47 (95%CI = 1.04-2.09), P = 0.032]. Trial sequential analysis corroborated findings of the traditional meta-analysis. However, we found that the conclusions of meta-analysis were strongly influenced by studies that deviated from the Hardy Weinberg equilibrium. A careful investigation of each study and a trial sequential analysis suggested that 677 C>T substitution holds no clinical significance in PCOS in most of the populations.

CONCLUSION

In conclusion, MTHFR 677 C>T polymorphism does not affect PCOS risk in India. The association seen in the meta-analysis is due to an outlier study and studies showing deviation from the Hardy Weinberg equilibrium.

Learning approach among health sciences students in a medical college in Nepal: a cross-sectional study

BACKGROUND

Many factors shape the quality of learning. The intrinsically motivated students adopt a deep approach to learning, while students who fear failure in assessments adopt a surface approach to learning. In the area of health science education in Nepal, there is still a lack of studies on learning approach that can be used to transform the students to become better learners and improve the effectiveness of teaching. Therefore, we aimed to explore the learning approaches among medical, dental, and nursing students of Chitwan Medical College, Nepal using Biggs's Revised Two-Factor Study Process Questionnaire (R-SPQ-2F) after testing its reliability.

METHODS

R-SPQ-2F containing 20 items represented two main scales of learning approaches, deep and surface, with four subscales: deep motive, deep strategy, surface motive, and surface strategy. Each subscale had five items and each item was rated on a 5-point Likert scale. The data were analyzed using Student's t-test and analysis of variance. Reliability of the administered questionnaire was checked using Cronbach's alpha.

RESULTS

The Cronbach's alpha value (0.6) for 20 items of R-SPQ-2F was found to be acceptable for its use. The participants predominantly had a deep approach to learning regardless of their age and sex (deep: 32.62±6.33 versus surface: 25.14±6.81, P<0.001). The level of deep approach among medical students (33.26±6.40) was significantly higher than among dental (31.71±6.51) and nursing (31.36±4.72) students. In comparison to first-year students, deep approach among second-year medical (34.63±6.51 to 31.73±5.93; P<0.001) and dental (33.47±6.73 to 29.09±5.62; P=0.002) students was found to be significantly decreased. On the other hand, surface approach significantly increased (25.55±8.19 to 29.34±6.25; P=0.023) among second-year dental students compared to first-year dental students.

CONCLUSION

Medical students were found to adopt a deeper approach to learning than dental and nursing students. However, irrespective of disciplines and personal characteristics of participants, the primarily deep learning approach was found to be shifting progressively toward a surface approach after completion of an academic year, which should be avoided.

Integrin beta 8 (ITGB8) regulates embryo implantation potentially via controlling the activity of TGF-B1 in mice

Integrins (ITGs) are mediators of cell-cell and cell-matrix interactions, which are also associated with embryo implantation processes by controlling the interaction of blastocyst with endometrium. During early pregnancy, ITGbeta8 (ITGB8) has been shown to interact with latent transforming growth factor (TGF) beta 1 (TGFB1) at the fetomaternal interface. However, the precise role of ITGB8 in the uterus and its association with embryo implantation has not been elucidated. Therefore, we attempted to ascertain the role of ITGB8 during the window of embryo implantation process by inhibiting its function or protein expression. Uterine plasma membrane-anchored ITGB8 was augmented at peri-implantation and postimplantation stages. A similar pattern of mRNA expression was also found during the embryo implantation period. An immunolocalization study revealed the presence of ITGB8 on luminal epithelial cells along with mild expression on the stromal cells throughout the implantation period studied; however, an intense fluorescence was noted only during the peri- and postimplantation stages. Bioneutralization and mRNA silencing of the uterine Itgb8 at preimplantation stage reduced the rate/frequency of embryo implantation and subsequent pregnancy, suggesting its indispensable role during the embryo implantation period. ITGB8 can also regulate the liberation of active TGFB1 from its latent complex, which, in turn, acts on SMAD2/3 phosphorylation (activation) in the uterus during embryo implantation. This indicates involvement of ITGB8 in the embryo implantation process through regulation of activation of TGFB1.

Combination Versus Monotherapy for the Treatment of HIV Associated Cryptococcal Meningitis

OBJECTIVE

To study the efficacy of anti Cryptococcal treatment by cerebrospinal fluid (CSF) fungal negativity after two weeks of treatment with amphotericin B alone or combined with fluconazole in treatment of HIV associated Cryptococcal meningitis (CM).

MATERIALS AND METHODS

A total of 84 human immunodeficiency virus (HIV) associated CM patients confirmed by CSF culture positivity were recruited for the study. Patients were randomly divided into two groups. Group A was given amphotericin B alone whereas Amphotericin B in combination with fluconazole was given in group B for the treatment of CM. Patients were followed for 14 days.

RESULTS

Maximum number of patients was in the age group 21-49 y. All the 84 patients had <100 CD4 counts/μl. After 14 days of the treatment in group A and B, there was no significant difference in terms of fever, headache and neck stiffness as a clinical outcome. But in group B there was improved in altered sensorium and focal neurological deficit as compared to group A. After 14 days of the treatment CSF culture negativity was more in group B as compared to group A.

CONCLUSION

Amphotericin B in combination with fluconazole is recommended for the treatment of HIV associated CM.

Systemic Sclerosis Sine Scleroderma

Systemic sclerosis sine scleroderma is a rare form of limited systemic sclerosis. These patients are without skin involvement, but do not differ in its clinical or laboratory features and prognosis from classical systemic sclerosis. In the absence of cutaneous signs/symptoms, its diagnosis is delayed leading to significant morbidity and mortality. We report a case of sixty year old female who presented to us with dyspnoea on exertion and Raynaud's phenomenon. She was investigated and was found to have this disorder with pulmonary artery hypertension.

Association of B12 deficiency and clinical neuropathy with metformin use in type 2 diabetes patients

CONTEXT

Long-term metformin use has been hypothesized to cause B12 deficiency and neuropathy in Type 2 diabetes patients. However, there is a paucity of Indian data regarding the same.

AIM

To compare the prevalence of B12 deficiency and peripheral neuropathy in patients with Type 2 diabetes mellitus treated with or without metformin.

MATERIALS AND METHODS

We recruited patients with Type 2 diabetes and divided them into metformin exposed and nonmetformin exposed groups. We measured baseline demographic variables like age, sex, vegetarian status, and HbA1c levels in both groups. We compared vitamin B12 levels and severity of peripheral neuropathy (using Toronto Clinical Scoring System (TCSS)) in both groups. Definite B12 deficiency was defined as B12 <150 pg/ml and possible B12 deficiency as <220 pg/ml. The difference in vitamin B12 levels and TCSS was calculated in both groups using independent samples t-test. Spearman's rank correlation between cumulative metformin use and B12 level was calculated. Odds ratio of vitamin B12 deficiency in metformin exposed group was also estimated.

RESULTS

Mean serum B12 levels was significantly lower in metformin exposed group (n=84) compared with nonmetformin exposed group (n=52) (410±230.7 versus 549.2±244.7, P=0.0011). Mean neuropathy score was significantly higher in metformin exposed group. (5.72±2.04 versus 4.62±2.12, P=0.0064). Odds ratio for possible B12 deficiency was 4.45 (95% CI 1.24-15.97). There was significant negative correlation between cumulative metformin dose and vitamin B12 level (r=-0.68, P<0.0001).

CONCLUSION

Metformin use is associated with vitamin B12 deficiency and clinical neuropathy in Type 2 diabetes patients.

PARP1 during embryo implantation and its upregulation by oestradiol in mice

Pregnancy requires successful implantation of an embryo, which occurs during a restricted period defined as ‘receptivity of the endometrium’ and is influenced by the ovarian steroids progesterone and oestradiol. The role of poly(ADP-ribose)polymerase-1 (PARP1) in apoptosis is well established. However, it is also involved in cell differentiation, proliferation and tissue remodelling. Previous studies have described the presence of PARP in the uterus, but its exact role in embryo implantation is not yet elucidated. Hence, in this study, we studied the expression of PARP1 in the uterus during embryo implantation and decidualisation, and its regulation by ovarian steroids. Our results show upregulation of the native form of PARP1 (∼116 kDa) in the cytosolic and nuclear compartments of implantation and non-implantation sites at day 5 (0500 h), followed by downregulation at day 5 (1000 h), during the embryo implantation period. The transcript level of Parp1 was also augmented during day 5 (0500 h). Inhibition of PARP1 activity by the drug EB-47 decreased the number of embryo implantation sites and blastocysts at day 5 (1000 h). Further, cleavage of native PARP1 was due to the activity of caspase-3 during the peri-implantation stage (day 5 (0500 h)), and is also required for embryo implantation, as inhibition of its activity compromised blastocyst implantation. The native (∼116 kDa) and cleaved (∼89 kDa) forms of PARP1 were both elevated during decidualisation of the uterus. Furthermore, the expression level of PARP1 in the uterus was found to be under the control of the hormone oestrogen. Our results clearly demonstrate that PARP1 participates in the process of embryo implantation.

Alternate Day versus Once Daily Atorvastatin for Primary Prevention of (CHD) in Naïve Patients of Dyslipidemia

INTRODUCTION

Statins (or HMG-CoA reductase inhibitors) have become drug of choice for raised Low-Density Lipoprotein Cholesterol (LDL-C) in treating. Of these, Atorvastatin, because of its prolonged 3-hydroxy-3-methylglutaryl-coenzyme A (HMG CoA) reductase inhibition has been considered for alternate day therapy in primary prevention of (CHD).

OBJECTIVES

To compare the efficacy and safety of daily versus alternate day 10 mg Atorvastatin on reduction of lipid levels in patients of dyslipidemia and to evaluate the number of patients reaching the target Low-Density Lipoprotein (LDL) goals in these groups.

METHODOLOGY

In this comparative, randomized, parallel group, non-blinded study, 100 naïve dyslipidemic patients in low to moderate risk group as per NCEP ATP (III) Guidelines were divided in two groups. Group A (n=50) received Atorvastatin 10 mg every alternate day for three months and Group B (n=50) received Atorvastatin 10 mg daily for three months. Apart from general examination and baseline investigations, lipid profile was also done. Efficacy was assessed by the percentage reduction in LDL and attainment of LDL goals as per NCEP ATP III Guidelines at the end of the study. Safety of the medication was assessed.

RESULTS

Atorvastatin 10 mg daily produced a significant reduction in Total Cholesterol (TC), LDL, Very Low Density Lipoprotein (VLDL) as compared to Atorvastatin 10 mg alternate day. The increase in the HDL level was also greater with a daily dose as compared to alternate day (but not statistically significant). In Low risk category 86.12 % patients (n=31) on daily dose reached their LDL-C goal vis-a-vis 66.67% (n=18) of patients on alternate day therapy. In the moderate risk category 100 % of daily Atorvastatin patients (n=10) achieved their LDL-C goal versus 33.33% patients (n=4) on alternate day therapy. Adverse events with alternate day therapy (n=4) were less as compared with daily treatment (n=10).

CONCLUSION

Atorvastatin 10 mg daily was found to be safe and efficacious in patients with dyslipidemia compared to an alternate day therapy.

Expression and activity of Rac1 is negatively affected in the dehydroepiandrosterone induced polycystic ovary of mouse

Background

Polycystic ovarian syndrome (PCOS) is characterized by the presence of multiple follicular cysts, giving rise to infertility due to anovulation. This syndrome affects about 10% of women, worldwide. The exact molecular mechanism leading to PCOS remains obscure. RhoGTPase has been associated with oogenesis, but its role in PCOS remains unexplored. Therefore, we attempted to elucidate the Vav-Rac1 signaling in PCOS mice model.

Methods

We generated a PCOS mice model by injecting dehydroepiandrosterone (DHEA) for a period of 20 days. The expression levels of Rac1, pRac1, Vav, pVav and Caveolin1 were analyzed by employing immuno-blotting and densitometry. The association between Vav and Rac1 proteins were studied by immuno-precipitation. Furthermore, we analyzed the activity of Rac1 and levels of inhibin B and 17β-estradiol in ovary using biochemical assays.

Results

The presence of multiple follicular cysts in ovary were confirmed by histology. The activity of Rac1 (GTP bound state) was significantly reduced in the PCOS ovary. Similarly, the expression levels of Rac1 and its phosphorylated form (pRac1) were decreased in PCOS in comparison to the sham ovary. The expression level and activity (phosphorylated form) of guanine nucleotide exchanger of Rac1, Vav, was moderately down-regulated. We observed comparatively increased expressions of Caveolin1, 17β-estradiol, and inhibin B in the polycystic ovary.

Conclusion

We conclude that hyperandrogenization (PCOS) by DHEA diminishes ovarian Rac1 and Vav expression and activity along with an increase in expression of Caveolin1. This is accompanied by an increase in the intra-ovarian level of '17 β-estradiol and inhibin B.

STAT3 and MCL-1 associate to cause a mesenchymal epithelial transition

Embryo implantation is effected by a myriad of signaling cascades acting on the embryo-endometrium axis. Here we show, by using MALDI TOF analysis, far-western analysis and colocalization and co-transfection studies, that STAT3 and MCL-1 are interacting partners during embryo implantation. We show in vitro that the interaction between the two endogenous proteins is strongly regulated by estrogen and progesterone. Implantation, pregnancy and embryogenesis are distinct from any other process in the body, with extensive, but controlled, proliferation, cell migration, apoptosis, cell invasion and differentiation. Cellular plasticity is vital during the early stages of development for morphogenesis and organ homeostasis, effecting the epithelial to mesenchymal transition (EMT) and, the reverse process, mesenchymal to epithelial transition (MET). STAT3 functionally associates with MCL-1 in the mammalian breast cancer cell line MCF7 that overexpresses STAT3 and MCL-1, which leads to an increased rate of apoptosis and decreased cellular invasion, disrupting the EMT. Association of MCL-1 with STAT3 modulates the normal, anti-apoptotic, activity of MCL-1, resulting in pro-apoptotic effects. Studying the impact of the association of STAT3 with MCL-1 on MET could lead to an enhanced understanding of pregnancy and infertility, and also metastatic tumors.