Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Sreenivas Vishnubhatla is active.

Publication


Featured researches published by Sreenivas Vishnubhatla.


Radiology | 2012

Pediatric Nonlymphoblastic Non-Hodgkin Lymphoma: Baseline, Interim, and Posttreatment PET/CT versus Contrast-enhanced CT for Evaluation—A Prospective Study

Sameer Bakhshi; Venkatraman Radhakrishnan; Punit Sharma; Rakesh Kumar; Sanjay Thulkar; Sreenivas Vishnubhatla; Deepa Dhawan; Arun Malhotra

PURPOSE To prospectively examine the roles of positron emission tomography (PET)/computed tomography (CT) and conventional contrast material-enhanced CT at baseline, after two cycles of chemotherapy, and after completion of chemotherapy in pediatric patients with nonlymphoblastic non-Hodgkin lymphoma (NHL) who were treated with similar standard treatment protocols. MATERIALS AND METHODS The institutional ethics committee approved the study protocol, and all patients were enrolled after written informed consent was obtained. Patients with nonlymphoblastic NHL were prospectively enrolled between January 2008 and March 2010. Patients underwent contrast-enhanced CT and PET/CT for staging and for response assessment after two cycles of chemotherapy (interim) and treatment completion. Complete metabolic response versus no metabolic response at PET/CT and complete response versus no complete response at contrast-enhanced CT was analyzed by using Kaplan-Meier survival analysis. RESULTS The final study included 34 patients with nonlymphoblastic NHL (median age, 10.5 years). Baseline PET/CT and contrast-enhanced CT showed concordance in depiction of 112 disease sites; PET/CT depicted 18 more disease sites and two fewer disease sites than contrast-enhanced CT (P = .0003). Disease in five of 34 patients was upstaged, and disease in no patient was downstaged at PET/CT. There was 100% (four of four) concordance between bone marrow involvement at biopsy and stage at PET/CT. The median length of follow-up was 20.3 months. Response at interim PET/CT and contrast-enhanced CT could not predict progression-free survival (PFS) (P = .083 and .18, respectively) or overall survival (OS) (P = .159 and.08, respectively). Posttreatment PET/CT and contrast-enhanced CT findings could predict PFS (P = .036 and .002, respectively) and posttreatment contrast-enhanced CT findings could predict OS (P = .035); however, posttreatment PET/CT findings could not predict OS (P = .067). CONCLUSION PET/CT depicts additional sites compared with contrast-enhanced CT and results in upstaging of disease. Either PET/CT or contrast-enhanced CT may be used for response assessment and prognostication in stage III or IV nonlymphoblastic pediatric NHL.


Journal of Pediatric Hematology Oncology | 2011

Oral Voriconazole Versus Intravenous Low Dose Amphotericin B for Primary Antifungal Prophylaxis in Pediatric Acute Leukemia Induction: A Prospective, Randomized, Clinical Study

Sushil Mandhaniya; Chetanya Swaroop; Sanjay Thulkar; Sreenivas Vishnubhatla; Sushil K. Kabra; Immaculata Xess; Sameer Bakhshi

Purpose: Invasive fungal infections (IFI) are a major cause of infection-related mortality during induction chemotherapy of acute leukemia (AL) patients. Data on antifungal prophylaxis (AFP) in children are limited by retrospective design, small sample size, and variability of chemotherapy phases having different risk of IFI. There are no data comparing voriconazole versus amphotericin B (AmB) as AFP in either adult/pediatric AL. The objectives of this study were to compare efficacy and toxicity of AmB and voriconazole as AFP in pediatric AL patients. Patients and Methods: As a pilot study, total 100 children (⩽15 y) with denovo acute myeloid leukemia and acute lymphoblastic leukemia were randomized to either oral voriconazole or low dose intravenous AmB as AFP during induction chemotherapy. Results: Failure of prophylaxis occurred in 14/50 patients in voriconazole arm (1 proven mucormycosis, 1 possible IFI, 11 empirical antifungal therapy, and 1 withdrawal owing to hepatotoxicity) and 17/50 patients in AmB arm (3 possible IFI, 13 empirical antifungal therapy, and 1 withdrawal owing to difficult venous access) (P=0.66). Of the 29 patients who had failure of prophylaxis unrelated to drug toxicity, computed tomography of the chest showed infiltrates in 10 patients with 3/12 in voriconazole arm and 7/16 in AmB arm (P=0.43). Drug-related serious adverse events were 6% versus 30% in voriconazole and AmB arms, respectively (P<0.01). Further, total number of toxicities per patient in AmB arm were significantly higher as compared with voriconazole arm (P<0.0001). Conclusion: This is the first randomized study comparing voriconazole with AmB in pediatric AL patients as AFP during induction chemotherapy; our results showed that oral voriconazole seems to be comparable with AmB with less toxicity and more convenience. (ClinicalTrials.gov identifier: NCT00624143).


British Journal of Haematology | 2010

Mitochondrial D-loop variations in paediatric acute myeloid leukaemia: a potential prognostic marker.

Surender Kumar Sharawat; Radhika Bakhshi; Sreenivas Vishnubhatla; Sameer Bakhshi

The D‐Loop region of mitochondrial DNA (mtDNA) is the regulatory region for its replication and transcription. There are two hypervariable regions (HV‐I, HV‐II) and the rate of mutation in these regions is 100‐ to 200‐fold that of nuclear DNA. In the current study, the entire D‐loop region of mtDNA was amplified in two overlapping polymerase chain reaction fragments and variations were evaluated in 44 paediatric acute myeloid leukaemia (AML) patients by direct DNA sequencing methods. Median age of the patients was 8·5 years (1–18 years) and the male:female ratio was 3·8:1. A total of 222 variations were observed at 118 positions in the D‐Loop of 35/44 (79·5%) AML patients. The most common variations were T→C (24·6%) and C→T (21·4%) followed by A→G (15·8%). There was no significant difference in the event‐free survival (EFS) of patients with or without any variations (P = 0·40). Three variations in HV‐I, namely 16126T→C (P = 0·05), 16224T→C (P < 0·01) and 16311T→C (P < 0·001), were significantly associated with inferior EFS. In conclusion, this is the largest study to show a high frequency of mtDNA variations in paediatric AML and their potential relevance as a prognostic marker in this disease.


Oncology | 2009

Clinical Profile, Etiology and Therapeutic Outcome in 324 Hepatocellular Carcinoma Patients at a Tertiary Care Center in India

Shashi Bala Paul; Sreenivasa Baba Chalamalasetty; Sreenivas Vishnubhatla; Kaushal Madan; Shivanand Gamanagatti; Yogesh Batra; Siddhartha Datta Gupta; Subrat Kumar Panda; Subrat K. Acharya

Objective: To study the profile and outcome of therapy for hepatocellular carcinoma (HCC) in India. Methods: Data analysis of HCC patients enrolled in liver clinic between 1990 and 2005. Results: We registered 324 HCC patients [males 284 (88%), mean age 52.4 ± 13.1 years]. The etiology of HCC was: hepatitis B virus 165 (51%), hepatitis C virus 38 (12%), alcohol 20 (6%), combined 31 (10%) and unknown 70 (21%). Serum α-fetoprotein was >400 ng in 36%, portal vein invasion was seen in 40% and distant metastases in 13%. Therapy was offered to 141 (43.5%) patients, but survival data was available in only 130 (93%) of them. Treatment given and median survival time was as follows: surgical resection, 19 months (n = 14); transarterial chemoembolization, 11 months (n = 23); transarterial rhenium therapy, 26 months (n = 7); radiofrequency ablation, 24 months (n = 4); acetic acid ablation, 13 months (n = 17); oral chemotherapy, 26 months (n = 33), and combination therapy, 26 months (n = 32). Vascular invasion, Okuda staging and therapy were independent factors associated with survival. Treated patients had longer median survival compared to untreated ones (16 months vs. 7 months, p < 0.05). Conclusions: Hepatitis B infection is the predominant cause of HCC in India. Serum α-fetoprotein was diagnostic in only one third of our patients. Most patients present late, when curative therapies are not possible. Treated patients had better survival than untreated ones.


Gynecologic Oncology | 2013

Neoadjuvant chemotherapy with weekly paclitaxel and carboplatin followed by chemoradiation in locally advanced cervical carcinoma: A pilot study

Rajkumar Bikramjit Singh; Subhash Chander; Bidhu Kalyan Mohanti; Sushmita Pathy; Sunesh Kumar; Neerja Bhatla; Sanjay Thulkar; Sreenivas Vishnubhatla; Lalit Kumar

OBJECTIVE To evaluate role of dose dense neo-adjuvant chemotherapy (NACT) prior to standard concurrent chemo-radiation (CCRT) in locally advanced cervical cancer. METHODS Between June 2010 and December 2011, 28 patients (median age - 51 years, range, 35 to 67 years) with locally advanced cervical cancer received NACT using paclitaxel (60 mg/m(2)) and carboplatin (AUC-2) weekly for 6 doses. After a mean interval of 15 days (range 7-23 days), the patients then received definitive radiation and concomitant weekly infusion of cisplatin (40 mg/m(2) for 6 doses). Response to concurrent chemo-radiation and toxicity were end points. RESULTS Following NACT, 67.8% of patients responded; complete (CR) - 2(7.1%), Partial (PR) - 17 (60.7%), stable 7 (25.0%) and 2 patients (7.1%) progressed. 24 of 28 patients received CCRT; 23/24 achieved CR. 22 of 23 complete responders continue to be in CR at a median follow-up of 12 months (range, 7 to 24 months). Grade III/IV neutropenia was the main hematological toxicity seen in 28.5% and 29% of patients, respectively during NACT and CCRT. CONCLUSIONS Neoadjuvant chemotherapy with dose dense weekly paclitaxel and carboplatin followed by standard CCRT is a feasible approach and is associated with a high response rate in locally advanced cervical cancer.


Journal of Stroke & Cerebrovascular Diseases | 2015

Seasonal Differences and Circadian Variation in Stroke Occurrence and Stroke Subtypes

Kishan Raj; Rohit Bhatia; Kameshwar Prasad; M.V.P. Srivastava; Sreenivas Vishnubhatla; Mamta Bhushan Singh

BACKGROUND India is a subtropical country with clear seasonal variations in weather conditions. Seasonal and circadian variation in occurrence of subtypes of cerebrovascular disease has been of interest in several studies from different countries and climate zones, but discrepant results have made the conclusions unclear. The aim of the present study was to observe the seasonal and circadian variation in the occurrence of stroke and its subtypes among our population. METHODS This was a cross-sectional observational study based on new cases and past cases of stroke on follow-up, conducted between January 2011 and December 2012 in the Department of Neurology, at the All India Institute of Medical Sciences, New Delhi, India. The date and time of onset of the stroke was recorded. The categorization of months into season was in accordance with the Indian Meteorological Department guidelines. The time of onset was distributed into 6 hourly intervals. Statistical calculations were performed using Stata version 12.1 and SPSS version 20. RESULTS A total of 583 patients were included for the study. The rate of occurrence of stroke was highest in the late morning 0600-1159 hours (P value <.001) compared with other times of the day, regardless of gender or age for both ischemic and hemorrhagic strokes. It was lowest in late evening (1800-2359 hours) quadrant compared with other quadrants. Although there was no significant difference found by dichotomizing the groups into two 6-month periods, there was an increasing trend in number of patients with stroke during the months November-February. There was no difference in stroke occurrence between the types of stroke or within each type among different seasons with different temperatures. Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification of ischemic strokes also did not show any association with season or circadian rhythm. CONCLUSIONS There is a significant increase in occurrence of strokes between 0600 and 1159 hours and lowest between 1800-2359 hours. No significant variation in stroke occurrence or subtype for any of the seasons was observed.


Pediatric Blood & Cancer | 2014

Evaluation of outcome and prognostic factors in extraosseous Ewing sarcoma

Bivas Biswas; N. K. Shukla; S. V. S. Deo; Sandeep Agarwala; Dayanand Sharma; Sreenivas Vishnubhatla; Sameer Bakhshi

Data on extraosseous Ewing sarcoma (EES) with uniform chemotherapy protocol are minimal. We aimed to examine this aspect in our patients, identify prognostic factors and compare the same with osseous Ewing sarcoma.


Pediatric Blood & Cancer | 2009

Noninvasive Imaging Surrogate of Angiogenesis in Osteosarcoma

Jyoti Bajpai; Shivanand Gamanagatti; Mehar Chand Sharma; Rakesh Kumar; Sreenivas Vishnubhatla; Shah Alam Khan; Shishir Rastogi; Arun Malhotra; Sameer Bakhshi

Measurement of tumor angiogenesis by qualitative analysis of dynamic contrast enhanced‐magnetic resonance imaging (DCE‐MRI), and its association with diffusion‐weighted (DW)‐MRI and glucose metabolism using positron emission tomography‐computerized tomography (PET‐CT) scan has not been explored in osteosarcoma. Present study was aimed to evaluate the potential of these surrogates.


Pediatric Hematology and Oncology | 2014

Circulating T-regulatory cells in neuroblastoma: a pilot prospective study.

Tvsvgk Tilak; Surender Sherawat; Sandeep Agarwala; Ritu Gupta; Sreenivas Vishnubhatla; Sameer Bakhshi

The objective of our study was to determine baseline Tregs in neuroblastoma patients and correlate with patient characteristics, their change with therapy and at relapse/progression. Flow-cytometric analysis for Treg cells [CD4+CD25+FoxP3+] was done in 14 de novo neuroblastoma patients at diagnosis, post-neoadjuvant chemotherapy and at relapse/progression, along with six healthy controls. Patients had significantly higher baseline Treg frequency than controls [Mean 9.84 ± 3.84 vs 3.16 ± 1.49, P < .001]; higher mean Treg frequency in patients with tumors >10 cm (P = .004) and there was significant reduction in Treg frequency with neoadjuvant chemotherapy when compared with the baseline value [Mean 3.07 ± 1.24 vs 9.72 ± 3.84, P = .007].


Leukemia & Lymphoma | 2013

Angiopoietins as biomarker of disease activity and response to therapy in multiple myeloma

Archana Bhaskar; Ritu Gupta; Sreenivas Vishnubhatla; Lalit Kumar; Atul Sharma; Mehar Chand Sharma; Prasenjit Das; Sonu Chand Thakur

Abstract Tumor angiogenesis is a complex process involving interplay of several angiogenic regulators. In the present study, mRNA expression and circulating levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), hypoxia inducible factor (HiF)-1α, circulating endothelial progenitor cells (cEPCs) and bone marrow microvessel density (MVD) were evaluated in multiple myeloma (MM). Compared to healthy controls, the levels of VEGF, bFGF, Ang-2, HiF-1α and cEPCs were significantly higher and Ang-1 and Ang-1/Ang-2 were lower in MM (p < 0.01). cEPC numbers correlated with Ang-1 (p = 0.03), Ang-2 (p = 0.01) and VEGF (p = 0.002). On multivariate analysis, reduced Ang-1/Ang-2 ratio (p = 0.005) at baseline was an independent predictor for response to therapy. After therapy, a decrease in Ang-2 (p < 0.001) and an increase in Ang-1/Ang-2 ratio (p = 0.003) were observed in responders. This study highlights the role of angiopoietins in MM which may, thus, be evaluated as potential targets for anti-angiogenic therapy in future.

Collaboration


Dive into the Sreenivas Vishnubhatla's collaboration.

Top Co-Authors

Avatar

Sameer Bakhshi

All India Institute of Medical Sciences

View shared research outputs
Top Co-Authors

Avatar

Atul Sharma

All India Institute of Medical Sciences

View shared research outputs
Top Co-Authors

Avatar

Lalit Kumar

All India Institute of Medical Sciences

View shared research outputs
Top Co-Authors

Avatar

Ritu Gupta

All India Institute of Medical Sciences

View shared research outputs
Top Co-Authors

Avatar

Sanjay Thulkar

All India Institute of Medical Sciences

View shared research outputs
Top Co-Authors

Avatar

Bidhu Kalyan Mohanti

All India Institute of Medical Sciences

View shared research outputs
Top Co-Authors

Avatar

Sandeep Agarwala

All India Institute of Medical Sciences

View shared research outputs
Top Co-Authors

Avatar

Surender Kumar Sharawat

All India Institute of Medical Sciences

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Vinod Raina

All India Institute of Medical Sciences

View shared research outputs
Researchain Logo
Decentralizing Knowledge