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The integrity of sperm deoxyribose nucleic acid (DNA) is one of the determinants that ensure normal fertilization, implantation, pregnancy, and the generation of a healthy progeny. Assessment of sperm DNA fragmentation has gained importance as a tool to provide significant information regarding sperm quality, and it can independently predict sperm fertilizing potential. The sperm chromatin dispersion (SCD) assay is one of the available techniques to detect sperm DNA damage with results comparable to the gold standard - Sperm Chromatin Structure Assay. We present here a detailed methodology of an alkaline modification of SCD that can be carried out with minimal laboratory equipment. The SCD assay is a modified halo assay that utilizes chemical methods to demonstrate sperm DNA fragmentation. It involves the embedding of sperms in an agarose medium followed by exposure to alkaline denaturation and deproteinization. The results are interpreted under a light microscope. A visual scoring system is utilized to differentiate the sperms with possible DNA fragmentation from those without fragmented DNA and to determine the sperm DNA fragmentation index (SDFI) % for each semen sample. The SDFI % is directly proportional to the quality of sperm. The SCD assay is a simple, cost-effective, and reliable technique that can detect sperm DNA fragmentation, thus providing information regarding sperm functional quality and reproductive capacity. It is of significance in clinical and research areas of andrology and reproductive medicine, toxicology, and pharmacotherapeutics.

Background and objective DNA damage analysis plays an important role in determining the approaches for treatment and prevention of various diseases like cancer, schizophrenia and other heritable diseases. Comet assay is a sensitive and versatile method for DNA damage analysis. The main objective of this work is to implement a fully automated tool for the detection and quantification of DNA damage by analysing comet assay images. Methods The comet assay image analysis consists of four stages: (1) classifier (2) comet segmentation (3) comet partitioning and (4) comet quantification. Main features of the proposed software are the design and development of four comet segmentation methods, and the automatic routing of the input comet assay image to the most suitable one among these methods depending on the type of the image (silver stained or fluorescent stained) as well as the level of DNA damage (heavily damaged or lightly/moderately damaged). A classifier stage, based on support vector machine (SVM) is designed and implemented at the front end, to categorise the input image into one of the above four groups to ensure proper routing. Comet segmentation is followed by comet partitioning which is implemented using a novel technique coined as modified fuzzy clustering. Comet parameters are calculated in the comet quantification stage and are saved in an excel file. Results Our dataset consists of 600 silver stained images obtained from 40 Schizophrenia patients with different levels of severity, admitted to a tertiary hospital in South India and 56 fluorescent stained images obtained from different internet sources. The performance of “CometQ”, the proposed standalone application for automated analysis of comet assay images, is evaluated by a clinical expert and is also compared with that of a most recent and related software—OpenComet. CometQ gave 90.26% positive predictive value (PPV) and 93.34% sensitivity which are much higher than those of OpenComet, especially in the case of silver stained images. The results are validated using confusion matrix and Jaccard index (JI). Comet assay images obtained after DNA damage repair by incubation in the nutrient medium were also analysed, and CometQ showed a significant change in all the comet parameters in most of the cases. Conclusions Results show that CometQ is an accurate and efficient tool with good sensitivity and PPV for DNA damage analysis using comet assay images.

1. Objectives The main objective is to develop a fully automated system for Deoxyribo Nucleic Acid (DNA) damage analysis using silver stained comet assay images for clinical applications. 2. Materials and methods Silver stained comet assay images of lymphocytes obtained from confirmed cases of Schizophrenia were employed for DNA damage analysis using Single Cell Gel Electrophoresis (SCGE) or Comet assay. The image analysis consists of three stages: (1) Comet segmentation by incorporating shading correction, pre-processing stages for image enhancement, noise filtering and thresholding; (2) Comet partitioning by fuzzy clustering and (3) Comet quantification stage in which the limitations of fuzzy clustering are eliminated. 3. Results This study involves 40 cases of Schizophrenia. Results of the proposed method are compared with those of OpenComet and CometScore software. Comet segmentation result is validated with a confusion matrix which shows better values for all performance indices. The proposed technique gave 87.12% Positive Predictive Value (PPV) and 90.16% sensitivity. It shows a large improvement in PPV and sensitivity, over the most recent competitive method, OpenComet. Regression analysis is carried out to validate the quantification results. Visual scores evaluated by the expert and DNA (%) in tail are used for finding the coefficient of determination, r 2 statistic. The proposed method gives a better r 2 value of 0.9. The performance of the proposed method is evaluated by a clinical expert. 4. Conclusion The proposed method is found to be very efficient for DNA damage analysis of silver stained comet assay images in the area of clinical research.

The etiology of schizophrenia continues to be confounding and elusive. Some knowledge gaps exist in the neurodegenerative theory of schizophrenia. Oxidative DNA damage and repair deficits are relevant to the mechanisms of neurodegeneration but have not been studied in drug naive schizophrenia. The present study used the comet assay technique to study the extent of DNA damage in circulating peripheral lymphocytes of patients with drug naive schizophrenia (n = 40) along with an age and gender matched control group (n = 40). We also assessed the DNA repair efficiency in cases following incubation in a nutrient medium. All the assayed comet parameters demonstrated significantly greater baseline DNA damage in cases in comparison to the controls except for head diameter (p < 0.001 for all significant results, p = 0.32 for head diameter). Gender, age and duration of illness (p = 0.21, 0.69 and 0.12 respectively for tail length) did not influence any of the parameters significantly. Significant decrease was noted in the comet tail length and percentage of DNA in comet tail (p < 0.001 for both) in cases following incubation suggesting that the DNA repair machinery was preserved. No difference in DNA repair efficiency was noted between the genders (p = 0.23 for tail length). Our findings confirm the presence of significant baseline DNA damage in schizophrenia even prior to the initiation of anti-psychotic treatment. Additionally, intact genomic repair efficiency was noted in this group as a whole. These results provide some evidence for oxidative DNA damage as molecular link underpinning neurodegeneration in drug naive schizophrenia.

The coordinated multi point (CoMP) transmission technique is considered a key feature in future wireless network to improve both cell edge users throughput by exploiting interference. However, to provide CoMP transmission several BSs need to be active, which eventually increases network energy consumption. The simultaneous active multiple BSs with different transmission characteristics in heterogeneous environment cause interferences on each other. In this paper, we study the energy efficient radio resource management (EE-RRM) scheme for heterogeneous wireless networks to reduce interference. In particular, our aim is to allocate subcarrier power by optimizing EE metric and minimize interference with knowledge of channel state information between BSs and user equipment. The EE-RRM problem is a fractional programming problem. In order to solve, we use Charnes---Cooper transformation technique and transform it into an equivalent concave optimization problem. The numerical results of our work present the effect of different interference, rate and power thresholds on the EE metric.

A flipped classroom is a learner centered approach in which the learner is responsible to attend the class with basic understanding of the subject to fully participate and engage in discussions. The aim of this study was to evaluate students' perception of flipped classroom approach for neuroanatomy module and assess the impact on their performance and attitudes. The subject chosen to evaluate the flipped classroom model for first year medical students was clinical neuroanatomy. One hundred and thirty first year medical students participated in the study module. Students were divided into five groups and five case scenarios pertaining to various clinically relevant regions of the neuraxis, with varying anatomical complexity were generated. The pre- and post-tests were designed to specifically test the declared learning objectives of the session. The perception of the students regarding this model of teaching and learning was also evaluated. Eighty-six percent of students felt that the flipped classroom approach was better at fulfilling the stated learning objectives than the conventional didactic teaching, 92% felt that the work-sheet with questions provided prior to the class enabled a better understanding of the subject and 87% were of the opinion that the web sources with references kindled a greater interest to read as compared with didactic lectures. The paired t test showed highly significant differences between the pre and post-test scores. Student response to the flipped classroom structure was largely positive, indicating it to be an approach worth pursuing in future years.

Comet assay is a well known method for evaluating DNA damage in individual cells. Silver stained comet assay images are employed in this study as they are widely used in clinical applications. When compared with fluorescent images silver stained images require additional pre-processing stages to effectively identify the region of interest. An improved method for effective automatic identification of true comets from the noisy silver stained images is proposed in this paper. The performance of the proposed method is compared with the recent related methods and shows better results in terms of %TP, %FN, %FP, Positive Predictive Value and sensitivity.

Hyperglycemic mothers have increased oxidative stress during pregnancy, which can adversely affect the outcome in their neonates.To measure the oxidative stress and DNA damage in newborns born to mothers with hyperglycemia and correlate their immediate outcome with the amount of oxidative stress and DNA damage.This prospective cohort study conducted in a tertiary care teaching hospital, South India included three groups - newborns born to pregestational diabetic mothers, gestational diabetic mothers, and euglycemic mothers with 24 newborns in each. Oxidative stress parameters - malondialdehyde (MDA), total antioxidant capacity (TAC), and DNA damage (comet assay) were assessed in umbilical cord blood. Association between these parameters and immediate neonatal outcome among three groups were studied.Newborns born to diabetic mothers had more MDA levels and DNA damage compared to euglycemic mothers. There was a positive correlation between comet parameters and MDA levels. There was an inverse correlation between comet parameters and TAC. Newborns born to diabetic mothers were at high risk to develop respiratory distress syndrome, hypoglycemia, and sepsis.Newborns born to diabetic mothers had increased oxidative stress and DNA damage compared to those born to mothers with euglycemia.

Abnormal communications among the branches of mandibular nerve especially the posterior division are significant due to various procedures undertaken in this region. These variations are worth reporting as they pose serious implications in several interventions in this region, and may even lead to false diagnosis. During routine dissection, the mandibular nerve and its branches were dissected in the infratemporal fossa. The branches from the posterior division of the mandibular nerve namely the inferior alveolar and auriculotemporal nerves were carefully dissected, and their abnormal branching pattern was noted. There was a communicating branch between left inferior alveolar and auriculotemporal nerve. There was also a variant recurrent branch from the left inferior alveolar nerve that supplied the lateral pterygoid muscle. Such variant branches and communications between the branches of mandibular nerve as seen in this case have an embryological basis and are clinically important in this region especially for dental surgeries and anesthesia.

Aim: This study aims at evaluating the chromosomal abnormalities and deoxyribonucleic acid (DNA) damage in cases with primary amenorrhea by karyotyping and comet assay. Study Design: A total of 30 cases of primary amenorrhea were recruited. Secondary sexual characters were assessed by Tanner staging. Chromosomal analysis was performed by conventional phytohemagglutinin stimulated lymphocyte cell culture technique. Alkaline version of comet assay was used to evaluate DNA damage. Results: The chromosomal pattern of 20 subjects (66.7%) was found to be normal (46,XX). Two subjects had 46,XY pattern and eight subjects had Turner syndrome (45,X or 45,X/46,XX). The comet parameters were found to be increased among subjects with 45,X monosomy, when compared to the rest of the study group and also in subjects with Tanner stage 1 when compared to stage 2. Conclusion: Comet assay revealed increased DNA damage in cases with 45,X monosomy, compared with subjects with 46,XX and 46,XY karyotype, which correlated with clinical features.

35 cases of 27-68years old breast cancer individuals and 15 female individuals of FDFRS formed the material for the current study. An equal number of normal healthy females controls were also included to investigate the extent of DNA damaged in cases, FDFRs and controls. 'Comet assay' was done by conventional methods with slight modifications. For Comet metrics, a Trinocular research microscope, Nikkon Optiphot model with automatic photomicrograph attachment was used. Thus quantification of the DNA damage was done by measuring comet tail length in all the three groups (cases, FDFRs and controls). There was significant increase in the mean comet tail length from controls to FDFRs (p Mean comettail length wasfound to be increased significantly in the advanced stage of carcinomas, i.e. stage III B followed by stage III A and II A. The FDFRs of breast carcinoma individuals showed significant level of DNA damage. This may be used as a marker/tool forthe identification of the diseased condition which gets manifested infamilies.

Sciatic nerve divides into tibial nerve and common peroneal nerve at the level of superior angle of popliteal fossa and variations in its branching pattern are common. The most common nerve entrapment syndrome in the lower limbs is common peroneal nerve entrapment at fibular head. Invariably it can also be trapped in gluteal region due to split piriformis muscle which compresses sciatic nerve as whole or its division such as common peroneal nerve. In this case report, we describe a case of high division of sciatic nerve along with duplicated piriformis associated with a communicating branch between inferior gluteal nerve and common peroneal nerve. Such an anatomical variation of common peroneal nerve with the communicating nerve is discussed with its embryological basis.Keywords: Common peroneal nerve, inferior gluteal nerve, nerve entrapment, piriformis, sciatic nerve

Introduction: Majority of the developmental delays in children are non-syndromic and they are believed to have an underlying DNA damage, though not well substantiated. Hence the present study was carried out to find out if there is any increased DNA damage in children with non-syndromic developmental delay by using the comet assay. Aim: The present case-control study was undertaken to assess the level of DNA damage in children with non syndromic developmental delay and compare the same with that of age and sex matched controls using submarine gel electrophoresis (Comet Assay). Materials and Methods: The blood from clinically diagnosed children with non syndromic developmental delay and controls were subjected for alkaline version of comet assay – Single cell gel electrophoresis using lymphocytes isolated from the peripheral blood. The comets were observed under a bright field microscope; photocaptured and scored using the Image J image quantification software. Comet parameters were compared between the cases and controls and statistical analysis and interpretation of results was done using the statistical software SPSS version 20. Results: The mean comet tail length in cases and control was 20.77+7.659μm and 08.97+4.398μm respectively which was statistically significant (p

Background & aim : Early diagnosis of neonatal sepsis is important for effective management and recovery. The available methods for diagnosis were not useful in predicting outcome. In the present study the technique of single cell gel electrophoresis [comet assay] which measures DNA damage was used to predict the outcome of neonatal sepsis. Material & methods : Comet Assay [single cell gel electrophoresis, SCGE] was used as a tool to assess the DNA damage in 3 5 term neonates with sepsis .The comet parameters were compared between those who recovered and expired due to sepsis neonatorum. Results were analysed using independent student t test with SPSS software version 19. p values

Increased levels of DNA damage and ineffective repair mechanisms are the underlying bio-molecular events in the pathogenesis of most of the life-threatening diseases like cancer and degenerative diseases. The sources of DNA damage can be either exogenous or endogenous in origin. Imbalance between the oxidants and antioxidants resulting in increased reactive oxygen species mostly accounts for the endogenously derived attacks on DNA. Among the various methods employed in the estimation of DNA damage, alkaline comet assay is proven to be a relatively simple and versatile tool in the assessment of DNA damage and also in determining the efficacy of DNA repair mechanism. The aim of this article is to review the application of comet assay in the field of medicine towards human biomonitoring, understanding the pathogenesis of cancer and progression of chronic and degenerative diseases, prediction of tumour radio & chemosensitivity and in male infertility. A standardized protocol and analysis system of various variants of comet assay in different types of cells, across the labs will be of useful and reliable clinical tool in the field of Medicine for the estimation of levels of DNA damage and repair mechanisms.

In CoMP, simultaneous transmission from several neighbouring base stations (BS) in heterogeneous network can exploit the interference to enhance system performance. Simultaneously, participation of several BSs will also increase the energy consumption of network. Therefore, this technique needs to be analysed properly for energy saving, especially for heterogeneous scenario, where different BSs have different characteristics. In this paper, we have analysed the performance of wireless system in heterogeneous environment without and with CoMP in terms of outage probability and energy efficiency by changing coverage range.

In heterogeneous network several types of base station (BSs) are deployed to satisfying user traffic demands of future communication system and improve network performance. The coordinated multi point (CoMP) transmission technique is considered a key feature in future wireless network to improve both cell edge users throughput by exploiting interference. However, to provide CoMP transmission several BSs need to be active, which eventually increases network energy consumption. Therefore, there is need to investigate the effectiveness of CoMP technique for energy efficient communication, especially in heterogeneous network scenario, where different BSs have different characteristics. In this paper, we investigate the performance of wireless system in heterogeneous environment without and with CoMP. In particular, we analysed network outage with its energy consumption efficiency with varied coverage range. Mobiles are assumed to be connected to nearest BSs. Furthermore, we have also investigated energy efficiency vs. outage probability in terms of number of coordinating BSs for joint-transmission enabling sleep mode mechanism.

Embalming is a process of preservation of dead body by injecting preservative fluid through arteries. Embalming of dead bodies is done if the body is going to be used either for academic purpose or has to be transported. In the absence of near relative of the deceased, a medical social worker accompanying the deceased requested for funeral embalming to enable transportation through the aeroplane. There are no provisions for funeral embalming in any of the Anatomy Acts enacted in various States in India. So, there is a need to formulate guidelines for transportation of embalmed dead body through air, rail, and road as the procedure is not done routinely like in western countries. Keywords: Funeral embalming, Anatomy Act, Medical social worker, Near relative

Studies have identified the risk factors like folic acid deficiency during gestational period, family history for orofacial clefts, drugs like antiepileptic, vitamin A. But, the data regarding the folic acid status in children with cleft lip/palate is hardly evaluated in depth. Here, an assessment of folic acid and DNA damage were carried out in children with orofacial anomalies. Folic acid level and DNA damage were evaluated by folic acid assay (direct chemiluminescent technology) and single cell gel electrophoresis or comet assay method respectively. The mean value of plasma folic acid by direct chemiluminescent technology was 6.5±3.6 nmol/L and the normal value in children ranges from 11.3 to 47.6 nmol/L. The amount of damaged DNA, measured as the tail length of the comet in cases, was 19.4±8.9 ?m and the mean percentage of DNA in tail was 16.5±3.7. Folic acid deficiency could be the reason for DNA damage.

Background: Neonatal jaundice is a common condition that can be treated with phototherapy. Phototherapy may cause oxidative stress in addition to the usual side effects. Aim: In this study, the oxidative stress in babies with neonatal jaundice was assessed before and after phototherapy by estimating plasma malondialdehyde (MDA) level. Methods: Eighty babies with neonatal jaundice were chosen for the study. Among them, 40 babies whose total serum bilirubin level was >15 mg/dl formed the case group and the other 40 babies with total serum bilirubin level