Comparative evaluation of two different xenogenic acellular matrices on full-thickness skin wound healing.

OBJECTIVE: The purpose of the study was to compare the healing potential of bubaline small intestinal matrix (bSIM) and fish swim bladder matrix (FSBM) on full-thickness skin wounds in rabbits. METHOD: Four full-thickness skin wounds (each 20×20mm) were created on the dorsum of 18 rabbits that were divided into three groups based on treatment: untreated sham control (I), implanted with double layers of bSIM (II) and implanted with double layers of FSBM (III). Macroscopic, immunologic and histologic observations were made to evaluate wound healing. RESULTS: Gross healing progression in the bSIM and FSBM groups showed significantly (p<0.05) less wound contraction compared with the sham group. The IgG concentration in rabbit sera was significantly (p<0.05) lower in the FSBM group compared with the bSIM group by enzyme-linked immunosorbent assay. The stimulation index of peripheral blood lymphocytes was significantly (p<0.05) lower in the FSBM group compared with the bSIM group by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Implantation of FSBM resulted in improved re-epithelialisation, neovascularisation and fibroplasia. CONCLUSION: The FSBM is a more effective dermal substitute when compared with the bSIM for full-thickness skin wound repair in rabbit.

KGHeBTA (King George's Medical University Hepatitis B Therapeutic Algorithm): A New Diagnostic and Therapeutic Algorithm and Clinico-epidemiological Spectrum of Hepatitis B.

Background: Diagnostic and therapeutic algorithms given by various societies for hepatitis B are fragmented and complex. The clinico-epidemiologic spectrum of hepatitis B is not studied with large-scale data from our region. We aimed to develop a comprehensive algorithm for the treatment of hepatitis B and study its clinico-epidemiological spectrum. Methods: From 2014-2019, the clinico-laboratory data of hepatitis B surface antigen (HbsAg)-positive patients were prospectively recorded. King George's Medical University hepatitis B therapeutic algorithm (KGHeBTA) was developed on the basis of the standard existing guidelines. The prevalence of different clinical stages of HBsAg-positive patients was calculated and their treatment records reviewed. Testing circumstances and risk factors were noted. Results: Among 1,508 data record sheets, 421 were complete. According to the KGHeBTA algorithm, 221 had detectable hepatitis B virus DNA. 21% were cirrhotic and 79% non-cirrhotic. 72% were incidentally detected asymptomatic hepatitis B, 7% were hepatitis B with acute symptoms, 0.7% were acute hepatitis B, and 22% were chronic hepatitis B. 20% patients were eligible for antivirals and 80% patients were not eligible. 32% patients were actually treated with antivirals due to the inclusion of some special indications as pregnancy and family history. Screening during various medical illnesses (40%) was the most common and during health camps (0.2%), the least common testing approach. Road-side shaving (52%) was the most common and intravenous drug abuse (0.2%) and the least common risk factor for the detection of hepatitis B in our data pool. Conclusions: HBsAg-positive patients can be easily worked up and treated based on the proposed algorithm (KGHeBTA). About one fourth to one fifth of all HBsAg-positive patients were eligible and treated with oral antivirals. Most of the patients were incidentally detected asymptomatic hepatitis B screened during medical illnesses. Roadside shaving and intravenous drug abuse were the most and the least common risk factors.

Impact of Sleep Duration, Quality, and Chronotype on Learning and Academic Performance: A Cross-Sectional Study Among First Year Medical Students of a Tertiary Care Institute.

Introduction The link between sleep and cognitive processes, such as memory and learning, continues to be one of the most intriguing and perplexing theories. Undergraduate medical students in their first year are particularly vulnerable to sleep disturbances. Academic achievement and learning have been linked to sleep patterns, which include not only the quantity and quality of sleep but also the timing of sleep in relation to the natural sleep onsets, or chronotypes. There have been conflicting reports on the outcomes of sleep and relatively fewer researches focused on the impact of chronotypes on learning and academic achievement among medical students. The current study thus sought to determine the chronotypes of medical students, evaluate the quantity and quality of sleep, and determine the impact of these factors on learning and academic performance. Methods The study was conducted in the Department of Physiology, All India Institute of Medical Sciences (AIIMS) Gorakhpur, India. Sleep health was assessed in 167 first-year medical students using the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), morningness-eveningness questionnaire (MEQ), and sleep log books. Learning and memory assessment was performed using Raven's progressive matrices test. Grade point average (GPA) was used to assess their academic performance. The relationship of sleep scores with GPA and RPM scores were obtained by linear regression analysis. One-way analysis of variance (ANOVA) and unpaired t-test were used to investigate other comparisons among categories of chronotypes and those of mean GPA. A p-value of <0.05 was considered as significant. Results The mean GPA and RPM scores obtained in the groups with PSQI ≥ 5 (2.67 ± 1.1, 49.51 ± 6.24, respectively) and PSQI < 5 (3.15 ± 0.59, 54.73 ± 4.01, respectively) and those in the group with ESS ≥ 10 (2.72 ± 1.17, 50.97 ± 5.92, respectively) and ESS < 10 (3.15 ± 0.6, 54.18 ± 3.91, respectively) varied with statistically significant differences (p < 0.05). Statistically significant R-squared values for the relationship of PSQI and ESS scores with RPM and GPA scores were obtained. No correlation between academic grades and chronotype was found. Poor GPA scores were found to be associated with reduced mean sleep duration for one week before the exams. Conclusion Learning and academic performance are negatively impacted by poor sleep quality and daytime sleep dysfunction. No definite evidence for the association of sleep chronotypes with the learning and memory could be attained. Higher test performance is more closely linked to the average sleep length over a duration of time preceding the exams.

Decellularization of caprine esophagus using fruit pericarp extract of Sapindus mukorossi.

Biological detergents like sodium deoxycholate, sodium dodecyl sulphate and Triton X-100 impairs the collagenous and non-collagenous proteins, glycosaminoglycans and growth factors. Further, certain chemical and enzymes are responsible for residual cytotoxicity in the decellularized extracellular matrix. The main focus of this study was to explore the decellularization property of soap nut pericarp extract (SPE) for development of decellularized tubular esophageal scaffold. For this 2.5, 5.0 and 10% concentrations of SPE were used for decellularization of caprine esophageal tissues. Histological analysis of hematoxylin and eosin and Masson's trichrome stained tissue samples confirmed decellularization with preservation of extracellular matrix microarchitecture. Scanning electron microscopic images of luminal surface of decellularized esophageal matrix showed randomly oriented collagen fibres with large interconnected pores and cells were absent. However, the external surface was more textured with fibrous structures and collagen fibres were well preserved. DAPI stained decellularized tissues revealed complete removal of nuclear components, verified by DNA content measurement and SDS-PAGE. The FTIR spectra of decellularized esophagus shows absorption peaks of amide A, B, I, II and III. Elastic modulus of the decellularized esophagus scaffolds increased (P > 0.05) as compared to native tissues. Histological and scanning electron microscopic evaluation of in vitro seeded scaffolds showed attachment and growth of primary chicken embryo fibroblasts over and within the decellularized scaffolds. It was concluded that 5% SPE is ideal for preparation of cytocompatible decellularized caprine esophageal scaffold with well-preserved extracellular matrix architecture and, may be used as an alternative to biological detergents and other chemicals.

Decellularization of Skin Tissue.

Biomaterials science encompasses elements of medicine, biology, chemistry, materials, and tissue engineering. They are engineered to interact with biological systems to treat, augment, repair, or replace lost tissue function. The choice of biomaterial depends on the procedure being performed, the severity of the patient's condition, and the surgeon's preference. Prostheses made from natural-derived biomaterials are often derived from decellularized extracellular matrix (ECM) of animal (xenograft) or human (allograft) origin. Advantages of using ECM include their resemblance in morphology and three-dimensional structures with that of tissue to be replaced. Due to this, scientists all over are now focusing on naturally derived biomaterials which have been shown to possess several advantages compared to synthetic ones, owing to their biocompatibility, biodegradability, and remodeling properties. Advantages of a naturally derived biomaterial enhance their application for replacement or restoration of damaged organs/tissues. They adequately support cell adhesion, migration, proliferation, and differentiation. Naturally derived biomaterials can induce extracellular matrix formation and tissue repair when implanted into a defect by enhancing attachment and migration of cells from surrounding environment. In the current chapter, we will focus on the natural and synthetic dermal matrix development and all of the progress in this field.

Development of decellularized aortic scaffold for regenerative medicine using Sapindus mukorossi fruit pericarp extract.

The aim of this study is to develop a novel decellularization method using aqueous extract of soap nut pericarp (SPE) and its evaluation using hematoxylin-eosin staining, scanning electron microscopy, diamidino-2-phenylindol (DAPI) staining, mechanical testing, sodium dodecyl sulfate polyacrylamide gel electrophoresis and DNA quantification. The presently available decellularization agent raises some concerns due to the potential for presence of residual cytotoxic agents in the extracellular matrix. Histological analysis of hematoxylin and eosin and masson's trichrome stained processed aortic samples shows complete decellularization with preservation of extracellular matrix microarchitecture at 120 h. Further, staining of tissue samples with DAPI demonstrates complete removal of DNA fragments. Quantitative evaluation of DNA in the decellularized aorta tissues demonstrated a significant (P < 0.01) decrease in DNA content as compared to native tissues. Collagen quantification assay indicate no significant (P> 0.05) difference in its content between native and decellularized caprine aorta. Tensile strength of the decellularized scaffolds decreased non-significantly (P > 0.05) when compared to native tissues. There was no significant (P > 0.05) difference in young's modulus of elasticity, stiffness and stretch ratio between native aortic tissues and decellularized aortic scaffolds. Histological and scanning electron microscopic examination of in vitro cultured scaffold demonstrated the cell viability and proliferation of primary chicken embryo fibroblasts. SPE treatment is thus capable of producing cytocompatible decellularized caprine aorta scaffold with preservation of extracellular matrix architecture for vascular tissue engineering and could be applied widely as one of the decellularization agent.

Sleep quality and insulin resistance in adolescent subjects with different circadian preference: A cross-sectional study.

BACKGROUND: Studies have shown that alterations in the sleep cycle can predispose to several disorders. Most of the previous studies were done on the adults. Hence, the aim of the study was to see the effect of circadian disruption on the health of adolescent population. MATERIALS AND METHODS: In this cross-sectional study, 203 subjects were enrolled. Study subjects were divided into three groups: definite evening chronotype, intermediate chronotype, and definite morning chronotype. Sleep quality was measured by Pittsburgh Sleep Quality Index (PSQI). Daytime sleepiness and chronotype were measured by Epworth Sleepiness Score and Morningness-Eveningness Questionnaire Self-Assessment version, respectively. Two hours postprandial glucose was measured after oral glucose tolerance test. Fasting blood glucose and fasting insulin were measured. Homeostasis model of assessment for insulin resistance (HOMA-IR) was calculated. Data were summarized as mean ± standard deviation. Crude odds ratios and Karl Pearson's correlation coefficient of metabolic parameters with poor sleep were calculated. RESULTS: Statistically significant difference was found in the mean value of poor sleep quality, 2 h postprandial blood glucose level, and insulin resistance among subjects of three groups. Subjects of evening chronotype have more significant positive correlation of 2 h postprandial blood glucose level and HOMA-IR value with poor sleep quality when compared with subjects of intermediate and morning chronotypes. CONCLUSION: Subjects with evening chronotype are more prone for development of metabolic syndrome compared with subjects of intermediate and morning chronotypes if proper health policies are not adopted for adolescents.

Circadian Preference, Sleep Quality, and Health-impairing Lifestyles Among Undergraduates of Medical University.

Background/Aims Health-impairing lifestyle during adolescence is an important marker for poor health. An unhealthy lifestyle may lead to physical and psychological problems in adulthood. Most of the prior researches were done among the adult population. Therefore, we assessed the chronotype pattern and correlation of health-impairing lifestyles with sleep quality according to circadian typology in medical students. Material and Methods In this cross-sectional research, a total of 203 subjects were enrolled. All subjects were divided into definite evening chronotype (n = 73), intermediate chronotype (n = 87), and definite morning chronotype (n = 43). Electronic media use at bedtime and duration of media use, the timing of dinner, smoking, tobacco chewing, and alcohol consumption were assessed with the help of a preformed proforma. Physical activity, sleep quality, daytime sleepiness, and chronotype were assessed by International Physical Activity Questionnaire (IPAQ), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Score (ESS), and Morningness-Eveningness Questionnaire Self-assessment version (MEQ-SA), respectively. Results Subjects of the evening chronotype were suffering more with poor sleep quality. Evening chronotype had a significant (p < 0.05) positive correlation between poor sleep quality and sex, tobacco smoking, alcohol drinking, type of diet, and timing of dinner. Conclusion Circadian typology demonstrated the significant correlation of health-impairing lifestyles with sleep quality. From this observation, it might be a better way to plan their daily activities, in accordance with their chronotypes, benefiting not only their academic performance but also their quality of life.

Effect of CPAP Therapy in Improving Daytime Sleepiness in Indian Patients with Moderate and Severe OSA.

INTRODUCTION: Obstructive Sleep Apnoea (OSA) is a highly prevalent disease and a major public health issue in India. Excessive daytime sleepiness is an almost ubiquitous symptom of OSA. Epworth Sleepiness Scale (ESS) score is a validated objective score to measure the degree of daytime sleepiness. Continuous Positive Airway Pressure (CPAP) therapy has been established as the gold standard treatment modality for OSA patients. A few Indian studies have reported the effectiveness of CPAP therapy in improving ESS scores after 1st month of CPAP use. AIM: To observe both, short-term (one month) and long-term (three month) effects of CPAP therapy on ESS scores in moderate to severe OSA patients. MATERIALS AND METHODS: The patients complaining of excessive day-time sleepiness, snoring and choking episodes during sleep, consecutively presenting to medicine OPD over a period of 2 years, were subjected to Polysomnography (PSG). Seventy-three patients with apnoea-hypopnea index (AHI) ≥15 were categorised as having moderate to severe forms of OSA (moderate OSA with AHI=15-30 and severe OSA with AHI >30), and were scheduled for an initial trial of CPAP therapy. Forty-seven patients reported good tolerance to CPAP therapy after a trial period of 2 weeks and comprised the final study group. ESS scores in these patients were recorded at the baseline, and after 1st and 3rd month of CPAP therapy, and statistically analysed for significance. RESULTS: Mean ESS score at the baseline among moderate and severe OSA patients were 13.67±2.29 and 16.56 ±1.87, respectively. ESS score in both these subgroups improved significantly to 11.63±3.79, p=0.022, CI (0.3293-4.0106)} and 14.13 ±3.74, p < 0.001, CI (1.2991-4.5408), respectively after one month of CPAP therapy. Likewise, mean ESS scores among moderate and severe OSA patients improved significantly to 9.84 ±2.97, p = 0.022, CI (0.3293-4.0106) and 12.29 ±3.97, p <0.001, CI (2.9414-6.1385), respectively after three months of CPAP therapy. CONCLUSION: The result of the present study shows that CPAP therapy is significantly effective in improving ESS scores in Indian patients having moderate to severe OSA. Benefits in daytime sleepiness were observed after short-term as well as long-term use of CPAP therapy.

Role of Vitamin-D in the prevention and treatment of Alzheimer's disease.

Alzheimer's disease is the most common form of age related cognitive impairment. Aim of the present study was to see the effect of vitamin D on cognitive function in elderly. The study was conducted in Department of Physiology, King George's Medical University (KGMU). A total of 80 subjects were enrolled based on Mini Mental State Examination (MMSE) score < 24 and vitamin D deficiency. They were divided into two groups as Group A (case) and Group B (control), each group having 40 subjects. Intervention (Vitamin D supplementation) was given in Group A. The assessment of dementia was done by Mini Mental State Examination (MMSE) score. Every subject was clinically evaluated and estimation of vitamin D was done by direct ELISA kit. Gender, weight, height, BMI, residence and education were also similar between two groups. A significant (p=0.0001) change in MMSE score was observed in both Group A and Group B from baseline to 3 & 6 months and from 3 to 6 months, however, mean change was higher in Group A than Group B. In conclusion, vitamin D supplementation caused significant improvement in the cognitive performance in subjects with senile dementia.

Comparative histologic and immunologic evaluation of 1,4-butanediol diglycidyl ether crosslinked versus noncrosslinked acellular swim bladder matrix for healing of full-thickness skin wounds in rabbits.

BACKGROUND: Collagen-rich extracellular matrix from land-based mammalian tissues is increasingly used in regenerative medicine. However, its uses are associated with risk of disease transfer and may carry an ethnocultural stigma. In the present study, collagen-rich acellular swim bladder matrix (ASBM) from Rohu fish was prepared using sodium deoxycholate and crosslinked with 1,4-butanediol diglycidyl ether (BDDGE). Wound healing potential of ASBM and ASBM-BDDGE was compared in full-thickness skin wounds in rabbits. MATERIALS AND METHODS: Four full-thickness skin wounds (20 × 20 mm(2) each) were created on the dorsum of 18 rabbits and randomly divided into three equal groups. Wounds were left open, repaired with ASBM and ASBM-BDDGE in groups sham (I), ASBM (II), and ASBM-BDDGE (III), respectively. Planimetry, contracture, immunologic, and histologic observations were carried out to evaluate wound healing. RESULTS: Significantly (P < 0.05) lesser wound contraction was observed in ASBM (II) and ASBM-BDDGE (III) groups compared with sham (I) group. Total immunoglobulin G response in rabbit sera was decreased significantly (P < 0.05) in the ASBM-BDDGE (III) group compared with ASBM (II) group by enzyme-linked immunosorbent assay. Stimulation index of peripheral blood lymphocytes was decreased significantly (P < 0.05) in the ASBM-BDDGE (III) group compared with ASBM (II) group by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Histologically, improved epithelialization, neovascularization, fibroplasia, and best arranged collagen fibers were observed in ASBM (II) and ASBM-BDDGE (III) groups as early as on postimplantation day 21. CONCLUSIONS: Findings of this study indicate that BDDGE crosslinked ASBM derived from Rohu fish has potential for the clinical applications. Furthermore, it is expected that their clinical applications will not be limited by ethnocultural stigma.

Primary chicken embryo fibroblasts seeded acellular dermal matrix (3-D ADM) improve regeneration of full thickness skin wounds in rats.

Rat skins were deepithelialized and decellularized by hypertonic saline and sodium deoxycholate (SDC), respectively. Primary chicken embryo fibroblasts (P-CEF) were cultured and seeded on prepared acellular dermal matrix (ADM). A full thickness skin defect (20×20 mm(2)) was created in thirty-six rats and randomly divided into three equal groups. Defect was left open, repaired with ADM and ADM seeded with P-CEF (3-D ADM) in groups 1, 2 and 3, respectively. By day 28, the treated wounds healed completely without scar. By day 7 hydroxyproline contents was higher in group 3 as compared to groups 1 and 2. There was slightly more B cell response in animals implanted with ADM and 3-D ADM. At day 21, stimulation index was lower with acellular dermis antigen as compared to 3-D ADM antigen. In group 1 on day 3, the granulation tissue showed more inflammatory reaction, fibroplasia and neovascularization as compared to group 2 and 3. By day 28, there was complete epithelization was observed in all groups over. However, a large scar was observed in group 1. The graft was completely absorbed and replaced with densely thick and best arranged collagen fibers. On day 7, malonyldialdehyde and superoxide dismutase levels were significantly (P<0.05) increased in group 1. Reduced glutathione values increased and reached to near normal in groups 2 and 3. Catalase values were significantly (P<0.05) higher in group 1 at different time intervals. SEM samples of group 2 showed ingrowth of fibroblasts into acellular matrix at host graft junction. However, in group 3 fibroblasts were infiltrated within the pores of graft. It was concluded that P-CEF cells seeded ADM facilitated early and better healing.