Vishal Rajan - Academia.edu (original) (raw)

Papers by Vishal Rajan

European Urology Open Science, 2020

Analytical and clinical validation of the trucheckTM platform for diagnostic triaging of symptoma... more Analytical and clinical validation of the trucheckTM platform for diagnostic triaging of symptomatic cases suspected of prostate cancer

Oral Oncology, 2018

Objectives: To examine the utility of computed tomography (CT) imaging during routine surveillanc... more Objectives: To examine the utility of computed tomography (CT) imaging during routine surveillance for the detection of recurrent head and neck squamous cell carcinoma (HNSCC). Materials/Methods: Clinical characteristics of HNSCC patients treated between 2008-2017 with radiation therapy or concurrent chemoradiation were abstracted from medical records. In patients who achieved a complete response to treatment by positron emission tomography scan, surveillance CT scans were conducted to the maxillofacial area, neck, and chest every 3 months in year 1, every 6 months in year 2, and every 12 months in years 3 and beyond. Results: Within the entire cohort (n = 534), complete response was achieved in 446 patients (83.5%); of these, 84 (15.7%) patients had a recurrence. Among the 84 patients with disease recurrence, 25 (30%) patients remained alive, of which 15 (18%) underwent successful salvage treatment and became free of disease. Lung screening CT scans detected failure in 8 of these successfully salvaged patients. Among the 8 patients successfully salvaged for locoregional recurrence, 3 failures were asymptomatic at onset and detected by laryngoscope or dental exam.

The Laryngoscope, Dec 27, 2016

The effect of smoking and human papillomavirus (HPV) on overall survival (OS) of oropharyngeal sq... more The effect of smoking and human papillomavirus (HPV) on overall survival (OS) of oropharyngeal squamous cell carcinoma (OPSCC) patients undergoing concurrent chemotherapy (CCRT) remains unclear. Retrospective review. Clinical characteristics of OPSCC patients treated between 2008 and 2015 with CCRT were abstracted from medical records. OS curves and multivariate cox proportional hazard ratios (HRs) were examined. Of 120 evaluable patients, 71% had HPV(+) tumors. Median follow-up duration for the entire cohort was 41.5 months (range = 6-88 months). HPV(+) current smokers experienced significantly worse 5-year OS (73% alive vs. 36% alive, P = .01) and there was a similar trend in HPV(-) current smokers (66% alive vs. 31% alive, P = .28) compared to former/never smokers undergoing CCRT. In a multivariate cox proportional hazard model adjusted for age, gender, and overall tumor stage, HPV(+) current smokers experienced nearly a fourfold increase in overall mortality in comparison to HPV...

The 2002 45th Midwest Symposium on Circuits and Systems, 2002. MWSCAS-2002.

Errors that arise from tolerance variations and mismatches between devices severely degrade the p... more Errors that arise from tolerance variations and mismatches between devices severely degrade the performance of bandgap reference circuits, which are essential building blocks to all highperformance systems. All these error sources have been analyzed (and verified through SPICE) and their design implications have been addressed. It has been found that resistor tolerance a d cmnt-mirror mismatch are the dominant sources of error in bandgap referencetype circuits. Further, it has been found that resistor mismatch, transistor mismatch, and current-mirror mismatch errors have a PTAT variation, while resistor tolerance error has a CTAT dependenceboth PTAT and CTAT errors are eliminated by trimming the PTAT terminating resistor in a bandgap circuit, only at room temperature. Resistor TC errors cannot be trimmed out and hence resisfors must therefore be carefully selected and designed.

Secure Path Loss Prediction in Fringe Areas Using Fuzzy Logic Approach

2009 International Conference on Advances in Computing, Control, and Telecommunication Technologies, 2009

Efficiency of present path loss models suffers when they are used in the environment other than f... more Efficiency of present path loss models suffers when they are used in the environment other than for which they have been designed. The aim of this paper is to propose the predicting the path loss with the field measurement models and represent them in a more convenient form for the proposed Fuzzy Logic modeling. This paper proposes method to predict path loss for correct location of base station in cellular mobile communication systems using fuzzy logic. The propagation medium is classified in to several well-established propagation environments defined as a fuzzy set such as free space, flat area terrain, light structures terrain, heavy structures terrain, and village terrain. A unique mean path loss exponent (n) is assigned to each propagation environment, which is established by means of the experimental. Fuzzy logic is used to determine ¿n¿ number for an unknown environment, which will be obtained using linguistic rules that provide a fine-tuning of the known propagation environments. HATA model proposed by M. Hata has been used for the present analysis.

Optimal stent expansion: is the eye of the beholder as good as intravascular ultrasound

The Journal of invasive cardiology, 2007

Spontaneous pneumobilia and air in the pancreatic duct

Clinics and research in hepatology and gastroenterology, 2012

s i p i b b i i c A 31-year-old female presented with intermittent, mild, right hypochondrial pai... more s i p i b b i i c A 31-year-old female presented with intermittent, mild, right hypochondrial pain of 2 years duration with no history of vomiting, jaundice, anorexia, significant weight loss, altered bowel habits, fever, and trauma. There has been no other relevant medical or surgical past history. General physical and abdominal examinations were noncontributory. Blood investigation, including liver function test, were within normal limits. Ultrasonography showed air in the gallbladder and in the dilated (8 mm) common bile duct (CBD) with no evidence of gallstones or CBD stones. Abdominal contrast enhanced computed tomography (CECT) confirmed the presence of pneumobilia (Fig. 1a) and pneumocholecyst (Fig. 1b), and also suspected the presence of a calculus at the lower end of the CBD. Air was present in the entire extrahepatic biliary tract; from the lower end of the CBD across the confluence into the right and left hepatic ducts (Fig. 1a). Presence of air was also noted in the cystic duct. In addition, CECT also revealed the presence of air in the main pancreatic duct in the head of the pancreas (Fig. 1b). The liver, gallbladder, biliary tract and pancreas were otherwise normal.

Neuromodulation of perineally transposed antropylorus with pudendal nerve anastomosis following total anorectal reconstruction in humans

Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society, 2014

We have reported perineal antropyloric segment transposition with its pudendal innervation as a r... more We have reported perineal antropyloric segment transposition with its pudendal innervation as a replacement for anal sphincter. Our aim herein was to neuromodulate this segment by electrical stimulation. Eight patients with a permanent colostomy underwent perineal antropyloric segment transposition followed by neural anastomosis of its anterior vagus branch to pudendal nerve branch in the perineum. Perineal antropyloric graft was assessed for its functional integrity and electrophysiological effects. Nerve stimulation was done by surface stimulation technique, using a customized stimulation protocol for smooth muscle. Antral pressures were recorded on voluntary attempts and on nerve stimulation with simultaneous concentric needle electromyography of the perineal antropylorus. The antral segment showed slow spontaneous contractions (2-3/min) on digital examination, endoscopy, and electrophysiology. Stimulated antropyloric electromyography showed a latency of 2-5 s with a differential...

International Journal of Computer Applications, 2012

Question Answering (QA) is a specific type of information retrieval. Given a set of documents, a ... more Question Answering (QA) is a specific type of information retrieval. Given a set of documents, a Question Answering system attempts to find out the correct answer to the question pose in natural language. Question answering is multidisciplinary. It involves information technology, artificial intelligence, natural language processing, knowledge and database management and cognitive science. From the technological perspective, question answering uses natural or statistical language processing, information retrieval, and knowledge representation and reasoning as potential building blocks. It involves text classification, information extraction and summarization technologies. In general, question answering system (QAS) has three components such as question classification, information retrieval, and answer extraction. These components play a essential role in QAS. Question classification play primary role in QA system to categorize the question based upon on the type of its entity. Information retrieval method is get of identify success by extracting out applicable answer post by their intelligent question answering system. Finally, answer extraction module is rising topics in the QAS where these systems are often requiring ranking and validating a candidate's answer. Most of the Question Answering systems consists of three main modules: question processing, document processing and answer processing. Question processing module plays an important part in QA systems. If this module doesn't work correctly, it will make problems for other sections. Moreover answer processing module is an emerging topic in Question Answering, in which these systems are often required to rank and validate candidate answers. These techniques aiming at discovering the short and precise answers are often based on the semantic classification. QA systems give the ability to answer questions posed in natural language by extracting, from a repository of documents, fragments of documents that contain material relevant to the answer.

Secure path loss prediction using fuzzy logic approach

2008 Fourth International Conference on Wireless Communication and Sensor Networks, 2008

Page 1. Secure Path Loss Prediction Using Fuzzy Logic Approach Akansha Gupta* SC Sharma Sandip Vi... more Page 1. Secure Path Loss Prediction Using Fuzzy Logic Approach Akansha Gupta* SC Sharma Sandip Vijay Vishal Gupta ... 867-870. 4. Dharm Prakash Agarwal and Qing-An Zeng, Introduction to Wireless and Mobile Systems, Thomson and Brooks/Cole, 2003, Pp: 63-87. ...

Anatomical basis of antropyloric transposition for fecal incontinence in humans: the infrapyloric approach

Surgical and Radiologic Anatomy, 2012

Antropylorus transposition in the perineum for end-stage anal incontinence has shown to be feasib... more Antropylorus transposition in the perineum for end-stage anal incontinence has shown to be feasible in humans. Vascular anatomy of the antro-pyloro-duodenal area is critical in preventing complications and increasing pyloric graft survival. This study was undertaken to examine the vascular anatomy of antro-pyloro-duodenal area in an attempt to safeguard the graft blood supply and improve its survival. After obtaining preoperative CT angiography to delineate the infrapyloric artery (IP a.), bench dissection of resected pancreaticoduodenectomy specimens was performed in 12 patients. Ex vivo angiography of these specimens were also performed. Subsequent to the information obtained from these dissections, the method of antropylorus mobilization during transposition was modified in terms of the site of division of the right gastroepiploic a. (Rt GEA). Perioperative outcomes (graft related complications, fecal incontinence scores, Doppler flow studies, and manometry studies of the graft) were compared between the two groups. IP a. originated only from the Rt GEA in 8 cases (66 %) and from both the gastroduodenal a. and the Rt GEA in the rest. However, its origin solely from the gastroduodenal a. was not observed. The pyloric graft survival, pyloric valve pressures and Doppler flow velocities were significantly…

Supportive Care in Cancer, 2013

Purpose-The purpose was to examine the effect of pretreatment weight status on loco-regional prog... more Purpose-The purpose was to examine the effect of pretreatment weight status on loco-regional progression for patients with squamous cell carcinoma of the head and neck (SCCHN) after receiving definitive concurrent chemoradiation therapy (CCRT). Methods-In an expanded cohort of 140 patients, we retrospectively reviewed weight status and loco-regional progression of SCCHN patients treated with CCRT between 2004 and 2010. Results-Pretreatment ideal body weight percentage (IBW%) was statistically significantly different for patients with disease progression than for those without progression (p=0.02) but was not an independent predictor of progression. Median pretreatment IBW% was 118 (72-193) for the progression-free group and was 101.5 (73-163) for the group with progression. Both groups suffered clinically severe weight loss of approximately 9 % from baseline to end treatment. Conclusions-Pretreatment weight status, a very crude indicator of nutrition status, may have prognostic value in patients with SCCHN undergoing definitive CCRT. Inadequate nutritional status in these patients has been associated with poor clinical outcomes and decreased quality of life. Based on this report and others, the best next steps include routine validated malnutrition screening and the testing of evidence-based nutrition care protocols with the goals of minimizing weight loss and improvement of quality of life.

Survival Differences between Organ Preservation Surgery and Definitive Radiotherapy in Early Supraglottic Squamous Cell Carcinoma

Otolaryngology–Head and Neck Surgery, 2013

ObjectiveSingle‐modality treatment, either with organ preservation surgery (OPS) or definitive ra... more ObjectiveSingle‐modality treatment, either with organ preservation surgery (OPS) or definitive radiation (RT), is the treatment of choice for patients with early supraglottic squamous cell carcinoma (SGC). However, studies comparing the effectiveness of these 2 techniques are lacking. This study compares the survival outcomes in early SGC patients treated with OPS versus RT.Study DesignSecondary data analysis.SettingSurveillance, Epidemiology and End Results database.Subjects and MethodsThis study included adult patients with early‐stage (T1N0, T2N0) SGC undergoing single‐modality treatment with either OPS (with or without neck dissection [ND]) or RT between 1988 and 2008. Survival analysis was used to compare the overall survival (OS) and disease‐specific survival (DSS) between patients treated with OPS+ND, OPS alone, and RT.ResultsA total of 2631 T1/T2 N0 SGC patients were identified, of whom 167 (6%) were treated with OPS+ND, 186 (7%) with OPS only, and 2278 patients (87%) with d...

Journal of Thoracic Oncology, 2009

Introduction: Multimodality therapy including extrapleural pneumonectomy (EPP), chemotherapy, and... more Introduction: Multimodality therapy including extrapleural pneumonectomy (EPP), chemotherapy, and radiotherapy (RT) is often recommended for fit patients with early stage malignant pleural mesothelioma. Planning RT after an EPP is difficult due to the large target area, the high doses required to prevent recurrence, and the proximity of critical structures. We studied patterns of local and nodal recurrence in patients treated at our institution with EPP and RT, and whether advanced treatment planning techniques, such as intensity modulated radiotherapy (IMRT), could have been of potential benefit. Methods: From 1993 to 2008, 86 patients with malignant pleural mesothelioma underwent EPP followed by hemithoracic RT (median dose: 54 Gy). The RT technique included a combination of photons and electrons to maximize dose to the target, whereas minimizing dose to normal tissues. After treatment, patients were followed with serial imaging and patterns of local and nodal failure were studied. Results: Median follow-up time for 78 analyzed patients was 17 months. Eight percent were in stage I, 35% stage II, 55% stage III, and 2% stage IV. Ten percent of all patients developed late grade 3 pulmonary toxicity and no patient died of RT. Fifteen patients failed in local and/or nodal sites and did not have a distant component to their failure pattern. Of these 15 patients, 10 failed in regions of dose inhomogeneity and could have possibly benefited from IMRT. Conclusions: The photon-electron technique was tolerable, but IMRT may provide better target coverage in some patients. IMRT's advantages must be balanced against the increased risk of fatal pulmonary toxicity.

Journal of Experimental Marine Biology and Ecology, 2010

The biochemical responses of Gracilaria corticata (J. Agardh) J. Agardh to salinity induced oxida... more The biochemical responses of Gracilaria corticata (J. Agardh) J. Agardh to salinity induced oxidative stress were studied following the exposure to different salinities ranging from 15, 25, 35 (control), 45 to 55 in laboratory conditions. The growth was highest under 25 (3.14 ± 0.69% DGR) and 35 (3.58 ± 0.32% DGR) and decreased significantly in both extreme lower (15) and hyper (55) salinities. Both phycoerythrin (PE) and allophycocyanin (APC) were significantly higher in hyper-salinity (45) with an increase of almost 70% and 52% from their initial contents. Conversely, the level of increase of the same in hypo-salinities was considerably lower as compared with that of hyper-salinity. Both hypo-and hyper-salinity treatments induced almost two fold increase in the contents of polyphenols, proline and the activities of antioxidative enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) especially for 6 d exposure. The Na + ions readily displaced the K + and Ca 2+ from their uptake sites at extreme hyper-salinity (55) and accounted for substantial increase in the ratio of Na + /K + and Na + /Ca 2+ that impeded the growth under long term exposure (N6 d). The survivability at salinity 45 even with considerably higher ratio of Na + /K + and Na + /Ca 2+ suggests the compartmentalization of Na + into the vacuoles. Further, the micro nutrients such as Zn, Fe and Mn were decreased at both high and low end salinities with highest at extreme hyper-salinity. The C18:1(n−9) cis, C18:2(n−6), C18:3(n−3) and C20:4(n−6) were found in significant amounts in hyper-salinities. The C18:1(n−9) cis in particular increased by 60.25% and 70.51% for salinities 45 and 55, respectively from their initial amounts. The ratio of total unsaturated to saturated fatty acids (UFA/SFA) also increased linearly with increasing salinity. These results collectively suggest the potential role of antioxidative enzymes, phycobiliproteins, PUFAs and mineral nutrients to combat the salinity induced oxidative stress in G. corticata.

Carney’s triad

Indian Journal of Gastroenterology, 2013

Head & Neck, 2012

Background-The purpose of this study was to quantify the effect of treatment duration on locoregi... more Background-The purpose of this study was to quantify the effect of treatment duration on locoregional progression after definitive concurrent chemoradiation (CCRT) for squamous cell carcinoma of the head and neck (SCCHN). Methods-We conducted a retrospective chart review of patients treated between 2004 and 2010. After a prior analysis, measures were taken to limit therapy beyond 7 weeks. Comparison of outcomes were made between cohorts 1 (2004-2007, n = 78) and 2 (2007-2010, n = 62). Results-Median therapy duration was statistically significantly different between cohorts as follows: 51 days, cohort 1 and 46 days, cohort 2 (p < .

Evidence for Autonomic dysregulation in irritable bowel syndrome

Gastroenterology, 2001

Gastroenterology, Volume 120, Issue 5, Pages A752, April 2001, Authors:Vishal Gupta; David Sheffi... more Gastroenterology, Volume 120, Issue 5, Pages A752, April 2001, Authors:Vishal Gupta; David Sheffield; G. Nicholas Verne.

Cornea, 2004

To determine the predisposing 1 factors, etiologic agents, and clinical and visual outcomes in in... more To determine the predisposing 1 factors, etiologic agents, and clinical and visual outcomes in infectious keratitis following lamellar keratoplasty (LK). Methods: One hundred thirty-five eyes (135 patients) that had undergone LK were retrospectively analyzed for the occurrence of infectious keratitis following LK. The parameters evaluated were predisposing factors, seasonal variation, indications and type of LK, time interval between LK and infection, site and depth of infection, etiologic organisms, type of treatment, outcome in terms of graft status, secondary surgery, visual acuity, and the donor tissue profile. Results: The incidence of infectious keratitis following LK was 11.11%. The most significant predisposing factor was persistent epithelial defect (3 eyes) and suture abscesses (3 eyes). Most cases occurred between May and August (9/15). Twelve cases developed infection within 2 weeks of surgery (80%). Seven cases (7/15) occurred with onlay grafts, 6 with inlay grafts, and 2 with large-diameter LK. Cultures of corneal scrapings were positive in 11 eyes (73.3%), and the most common isolated organism was coagulase-negative Staphylococcus (CNS). Only 2 eyes responded to medical therapy, and graft sloughing occurred in 9 cases. Six eyes underwent penetrating keratoplasty to either salvage the integrity of globe or for visual rehabilitation of cases where infection resulted in corneal opacity. Conclusions: Infections after LK may not be amenable to antimicrobial therapy and may necessitate the removal of the graft or a therapeutic penetrating keratoplasty.

Cardiovascular Pathology, 2009

Introduction-Extracellular matrix changes occur in many heart valve pathologies. For example, myx... more Introduction-Extracellular matrix changes occur in many heart valve pathologies. For example, myxomatous mitral valves are reported to contain excess proteoglycans (PGs) and hyaluronan (HA). However, it is unknown which specific PGs are altered in myxomatous valves. Because PGs perform varied functions in connective tissues, this study was designed to identify and localize three matrixassociated PGs as well as HA and the HA receptor for endocytosis (HARE) within myxomatous and normal mitral valves. Methods-Human mitral posterior leaflets (control n=6−9, myxomatous n=14−21, mean age 61 for all groups) were histochemically stained for PG core proteins, HA, and HARE. Stain intensity was semi-quantitatively graded to determine differences in marker abundance betweennormal and myxomatous valves. The PGs were localized to different regions of the leaflet by correspondence to parallel Movat stained sections Results-The PGs decorin, biglycan and versican were more abundant in myxomatous valves than in normal controls (p<0.03). There was a gender effect on PG presence but no age related trends were observed. HA and HARE were distributed throughout all valves. There was no significant difference in HA between groups, but HARE expression was reduced in myxomatous valves compared to normal controls (p<0.002). Conclusion-Excess decorin, biglycan and versican may be associated with the remodeling of other matrix components in myxomatous mitral valves. Decreased expression of HARE in myxomatous valves suggests that HA metabolism could be altered in myxomatous mitral valve disease. These finding contribute towards elucidating the pathogenesis of myxomatous mitral valve disease and developing potential new therapies.