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Featured researches published by Nirag Jhala.


Cancer Cell | 2012

Tumor-Derived Granulocyte-Macrophage Colony-Stimulating Factor Regulates Myeloid Inflammation and T Cell Immunity in Pancreatic Cancer

Lauren J. Bayne; Gregory L. Beatty; Nirag Jhala; Carolyn E. Clark; Andrew D. Rhim; Ben Z. Stanger; Robert H. Vonderheide

Cancer-associated inflammation is thought to be a barrier to immune surveillance, particularly in pancreatic ductal adenocarcinoma (PDA). Gr-1(+) CD11b(+) cells are a key feature of cancer inflammation in PDA, but remain poorly understood. Using a genetically engineered mouse model of PDA, we show that tumor-derived granulocyte-macrophage colony-stimulating factor (GM-CSF) is necessary and sufficient to drive the development of Gr-1(+) CD11b(+) cells that suppressed antigen-specific T cells. In vivo, abrogation of tumor-derived GM-CSF inhibited the recruitment of Gr-1(+) CD11b(+) cells to the tumor microenvironment and blocked tumor development-a finding that was dependent on CD8(+) T cells. In humans, PDA tumor cells prominently expressed GM-CSF in vivo. Thus, tumor-derived GM-CSF is an important regulator of inflammation and immune suppression within the tumor microenvironment.


The American Journal of Gastroenterology | 2003

Endoscopic ultrasound-guided fine needle aspiration biopsy of patients with suspected pancreatic cancer: diagnostic accuracy and acute and 30-day complications.

Mohamad A. Eloubeidi; Victor K. Chen; Isam Eltoum; Darshana Jhala; David C. Chhieng; Nirag Jhala; Selwyn M. Vickers; C.Mel Wilcox

OBJECTIVES:The aims of this study were to evaluate the diagnostic accuracy of endoscopic ultrasound–guided fine needle aspiration (EUS-FNA) in patients with suspected pancreatic cancer, and to assess immediate, acute, and 30-day complications related to EUS-FNA.METHODS:All patients with suspected pancreatic cancer were prospectively evaluated. A single gastroenterologist performed all EUS-FNAs in the presence of a cytopathologist. Immediate complications were evaluated in all patients. An experienced nurse called patients 24–72 h and 30 days after the procedure. Reference standard for the classification of the final diagnosis included: surgery (n = 48), clinical or imaging follow-up (n = 63), or death from the disease (n = 47).RESULTS:A total of 158 patients (mean age 62.3 yr) underwent EUS-FNA during the study period. The mean tumor size was 32 × 26 mm. The median number of passes was three (range one to 10). Of these patients, 44% had at least one failed attempt at tissue diagnosis before EUS-FNA. The sensitivity, specificity, PPV, NPV, and accuracy of EUS-FNA in solid pancreatic masses were 84.3%, 97%, 99%, 64%, and 84%, respectively. Immediate self-limited complications occurred in 10 of the 158 EUS-FNAs (6.3%). Of 90 patients contacted at 24–72 h, 78 patients (87%) responded. Of the 90 patients, 20 (22%) reported at least one symptom, all of which were minor except in three cases (one self-limited acute pancreatitis and two emergency room visits, one of which led to admission). In all, 83 patients were contacted at 30 days, and 82% responded. No additional or continued complications were reported.CONCLUSIONS:EUS-FNA is highly accurate in identifying patients with suspected pancreatic cancer, especially when other modalities have failed. Major complications after EUS-FNA are rare, and minor complications are similar to those reported for upper endoscopy. It seems that follow-up at 1 wk might capture all of the adverse events related to EUS-FNA.


Clinical Gastroenterology and Hepatology | 2004

Endoscopic ultrasound-guided fine needle aspiration biopsy of suspected cholangiocarcinoma

Mohamad A. Eloubeidi; Victor K. Chen; Nirag Jhala; Isam Eldin Eltoum; Darshana Jhala; David C. Chhieng; Sujath Syed; Selwyn M. Vickers; C. Mel Wilcox

BACKGROUND AND AIMS Despite advances in endoscopic techniques for sampling bile duct strictures, the diagnosis of cholangiocarcinoma remains a challenge. The purpose of this study was to evaluate the yield of EUS-FNA and its impact on patient management for patients with suspected cholangiocarcinoma. METHODS All patients undergoing EUS for the evaluation of suspected malignant biliary strictures were prospectively evaluated over a 23-month period. A single gastroenterologist performed all EUS-FNAs in the presence of a cytopathologist. Reference standard for final diagnosis included surgery, death from disease, and clinical and/or imaging follow-up. RESULTS Twenty-eight patients (mean age 67 years [SD +/- 11], 72% male) were evaluated. Most patients (91%) presented with obstructive jaundice, and all except 1 had nondiagnostic sampling of the biliary lesions either at ERCP (88%), percutaneous transhepatic cholangiogram (n = 2), and/or computed tomography-guided biopsy (n = 1). Sixty-seven percent (14/21) had no definitive mass seen on prior abdominal imaging studies. The mean tumor size by EUS was 19 mm x 16 mm with a median number of passes to diagnosis of 3 (range 1-7). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 86%, 100%, 100%, 57%, and 88%, respectively. EUS-FNA had a positive impact on patient management in 84% of patients: preventing surgery for tissue diagnosis in patients with inoperable disease (n = 10), facilitating surgery in patients with unidentifiable cancer by other modalities (n = 8), and avoiding surgery in benign disease (n = 4). CONCLUSIONS Given the apparent accuracy and safety of EUS with FNA for imaging bile duct mass lesions and for obtaining a tissue diagnosis in patients with suspected cholangiocarcinoma, this technology may represent a new approach to diagnosis especially when other methods fail. The ability to obtain a definite diagnosis has a significant impact on patient management.


Journal of Clinical Investigation | 2007

Inhaled NO accelerates restoration of liver function in adults following orthotopic liver transplantation

John D. Lang; Xinjun Teng; Phillip Chumley; Jack H. Crawford; T. Scott Isbell; Balu K. Chacko; Yuliang Liu; Nirag Jhala; D. Ralph Crowe; Alvin B. Smith; Richard C. Cross; Luc Frenette; Eric E. Kelley; Diana W. Wilhite; Cheryl R. Hall; Grier P. Page; Michael B. Fallon; J. Steven Bynon; Devin E. Eckhoff; Rakesh P. Patel

Ischemia/reperfusion (IR) injury in transplanted livers contributes to organ dysfunction and failure and is characterized in part by loss of NO bioavailability. Inhalation of NO is nontoxic and at high concentrations (80 ppm) inhibits IR injury in extrapulmonary tissues. In this prospective, blinded, placebo-controlled study, we evaluated the hypothesis that administration of inhaled NO (iNO; 80 ppm) to patients undergoing orthotopic liver transplantation inhibits hepatic IR injury, resulting in improved liver function. Patients were randomized to receive either placebo or iNO (n = 10 per group) during the operative period only. When results were adjusted for cold ischemia time and sex, iNO significantly decreased hospital length of stay, and evaluation of serum transaminases (alanine transaminase, aspartate aminotransferase) and coagulation times (prothrombin time, partial thromboplastin time) indicated that iNO improved the rate at which liver function was restored after transplantation. iNO did not significantly affect changes in inflammatory markers in liver tissue 1 hour after reperfusion but significantly lowered hepatocyte apoptosis. Evaluation of circulating NO metabolites indicated that the most likely candidate transducer of extrapulmonary effects of iNO was nitrite. In summary, this study supports the clinical use of iNO as an extrapulmonary therapeutic to improve organ function following transplantation.


American Journal of Clinical Pathology | 2003

Endoscopic Ultrasound-Guided Fine-Needle Aspiration A Cytopathologist's Perspective

Nirag Jhala; Darshana Jhala; David C. Chhieng; Mohamad A. Eloubeidi; Isam Eltoum

Endoscopic ultrasound (EUS) is used to detect and delineate the extent of lesions in the gastrointestinal tract, periluminal lymph nodes, pancreas and hepatobiliary tree, left kidney, spleen, and adrenal glands. EUS-guided fine-needle aspiration (FNA) has added a new dimension to the capabilities of EUS because it permits characterization of the lesion, thereby enabling triage of patients for more efficient and effective management. This review focuses on the advantages and limitations of EUS-FNA, including a discussion of potential pitfalls in the diagnosis of commonly aspirated deep-seated lesions, such as those of the pancreas and lymph nodes. It also addresses the practical considerations associated with establishing an effective service and the importance of an integrated approach in which the cytopathologist undertakes a key role, interacting extensively with the endoscopist and the patient management team. EUS-FNA is a sensitive modality that enables specific and accurate diagnosis of deep-seated lesions. Samples can be obtained effectively from small lesions (< 25 mm), irrespective of the organ site. On-site assessment permits a highly accurate preliminary diagnosis of malignancy for samples obtained by EUS-FNA and provides an opportunity to increase the diagnostic yield of samples.


Clinical Infectious Diseases | 2001

Symptomatic Lactic Acidosis in Hospitalized Antiretroviral-Treated Patients with Human Immunodeficiency Virus Infection: A Report of 12 Cases

Michael E. Coghlan; Jean-Pierre Sommadossi; Nirag Jhala; J. Many Wickliffe; S. Saag Michael; Victoria A. Johnson

We retrospectively investigated the clinical and histopathologic features of hospitalized patients infected with human immunodeficiency virus who had symptomatic lactic acidosis syndrome at a university teaching hospital during 1995-2000. Twelve patients were identified, 11 during 1998-2000; of these, 5 died with rapid progression to otherwise unexplained multiple-organ failure. All had extensive prior exposure to nucleoside analog reverse-transcriptase inhibitors (NRTIs). At presentation, the most commonly identified NRTI component of antiretroviral regimens was stavudine plus didanosine. Eleven patients presented with abdominal pain, nausea, and/or emesis. Eight patients had prior acute weight loss (mean [+/-SD], 12+/-5.3 kg). Median venous plasma lactate levels were > or =2-fold greater than the upper limit of normal (2.1 mmol/L). Serum transaminase levels were near normal limits at presentation. Histopathologic studies confirmed hepatic macrovesicular and microvesicular steatosis in 6 patients. Concurrent chemical pancreatitis was identified in 6 patients. The increasing number of cases identified during the study period suggests that physicians better recognize symptomatic lactic acidosis and/or that cumulative NRTI exposure may increase the risk for this syndrome.


Cancer Research | 2007

Inactivation of Smad4 Accelerates KrasG12D-Mediated Pancreatic Neoplasia

Kyoko Kojima; Selwyn M. Vickers; N. Volkan Adsay; Nirag Jhala; Hyung-Gyoon Kim; Trenton R. Schoeb; William E. Grizzle; Christopher A. Klug

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal human malignancies, with an overall 5-year survival rate of <5%. Genetic analysis of PDAC patient samples has shown that specific disease-associated mutations are correlated with histologically defined stages of neoplastic progression in the ductal epithelium. Activating mutations in KRAS are almost uniformly present in early-stage disease, with subsequent inactivating mutations in p16(INK4A), p53, and SMAD4 occurring in more advanced lesions. In this study, we have tested whether the loss of Smad4 would cooperate with an activating Kras(G12D) mutation to promote progression to PDAC using the Pdx1-Cre transgenic system to activate Kras(G12D) and delete Smad4 in all pancreatic lineages including the ductal epithelium. Analysis of double-mutant mice showed that loss of Smad4 significantly accelerated the progression of pancreatic intraepithelial neoplasias (mPanIN) and promoted a high incidence of intraductal papillary mucinous neoplasia and active fibrosis compared with Pdx1-Cre;Kras(G12D) or Pdx1-Cre;Smad4(lox/lox) mice. Occasionally, double-mutant mice progressed to locally invasive PDAC with little evidence of metastases by 6 months of age and without the detectable loss of p53 or p16(Ink4A) expression or function. The loss of Smad4 only seemed to promote disease progression in the presence of the activated Kras(G12D) allele because we observed no abnormal pathology within the pancreata of 23 Pdx1-Cre;Smad4(lox/lox) animals that were analyzed up to 8 months of age. This indicates that Smad4 is dispensable for normal pancreatic development but is critical for at least partial suppression of multiple Kras(G12D)-dependent disease-associated phenotypes.


American Journal of Clinical Pathology | 2003

Endoscopic Ultrasound–Guided Fine-Needle Aspiration

Nirag Jhala; Darshana Jhala; David C. Chhieng; Mohamad A. Eloubeidi; Isam Eltoum

Endoscopic ultrasound (EUS) is used to detect and delineate the extent of lesions in the gastrointestinal tract, periluminal lymph nodes, pancreas and hepatobiliary tree, left kidney, spleen, and adrenal glands. EUS-guided fine-needle aspiration (FNA) has added a new dimension to the capabilities of EUS because it permits characterization of the lesion, thereby enabling triage of patients for more efficient and effective management. This review focuses on the advantages and limitations of EUS-FNA, including a discussion of potential pitfalls in the diagnosis of commonly aspirated deep-seated lesions, such as those of the pancreas and lymph nodes. It also addresses the practical considerations associated with establishing an effective service and the importance of an integrated approach in which the cytopathologist undertakes a key role, interacting extensively with the endoscopist and the patient management team. EUS-FNA is a sensitive modality that enables specific and accurate diagnosis of deep-seated lesions. Samples can be obtained effectively from small lesions (<25 mm), irrespective of the organ site. On-site assessment permits a highly accurate preliminary diagnosis of malignancy for samples obtained by EUS-FNA and provides an opportunity to increase the diagnostic yield of samples.


The American Journal of Gastroenterology | 2006

Agreement between rapid onsite and final cytologic interpretations of EUS-guided FNA specimens : Implications for the endosonographer and patient management

Mohamad A. Eloubeidi; Ashutosh Tamhane; Nirag Jhala; David C. Chhieng; Darshana Jhala; D. Ralph Crowe; Isam Eltoum

BACKGROUND:The practice of onsite cytology interpretation varies across endoscopic ultrasound (EUS) programs in the Untied States and Europe. The value, reliability, and agreement of rapid onsite evaluation (ROSE) compared with final interpretation and its impact on patient management remain largely unknown. We compared agreement between ROSE of EUS-FNA (endoscopic ultrasound-guided fine needle aspiration) specimens with final cytology interpretation and their respective operating characteristics.METHODS:We prospectively evaluated consecutive EUS-FNA specimens obtained by a single endosonographer in the presence of an attending cytopathologist (July 2000–November 2002). The “agreement” between ROSE and final cytology interpretation was assessed by the “kappa” statistic. The frequency and possible reasons for discrepancy between ROSE and final cytologic interpretation were determined.RESULTS:A total of 540 patients (median age 63 yr, 77% white) underwent EUS-FNAs of 656 lesions. These included lymph nodes (LNs, N = 248), solid pancreatic masses (SPMs, N = 229), cystic pancreatic masses (CPM, N = 57), mural lesions (41), bile duct/gallbladder (N = 28), liver (N = 17), mediastinum/lung (N = 17), adrenal (N = 15), spleen (N = 3), and kidney (N = 1). Data were available for onsite evaluation in 607 lesions. Intitial cytology was benign (N = 243), atypical (N = 23), suspicious (24), malignant (300), and indeterminate (N = 17). Out of the 243 benign lesions interpreted by onsite evaluation, five lesions (2.1%) were upgraded to be malignant or suspicious for malignancy on final cytology report. Of the 300 lesions initially reported malignant on ROSE, 294 (98%) remained malignant on the final cytology. There was an excellent agreement between ROSE and final cytologic evaluation (kappa = 84.0%, 95% CI 80.2–87.7), Compared with the true final status, accuracy for final interpretation was slightly higher than for ROSE but was not statistically significant (95.8% vs 93.9%). Scant cellularity remained the most frequent reason for discrepancy, accounting for 21 of 51 discrepancies (41%). Other reasons for discrepancy included: cases requiring an intradepartmental consultation (22%), cases requiring ancillary studies (12%), intra-observer variability (10%), and challenging diagnosis (10%). In three cases, (6%) we were unable to determine the possible reason for discrepancy.CONCLUSION:ROSE of EUS-FNA specimens is highly accurate compared with final cytologic evaluation. Because the diagnosis of malignancy rarely changes, informing our patients and their families and our referring physicians of a cancer diagnosis significantly reduces physician work load and expedites patient management. The majority of discrepancies are related to the nature of the lesion either because it sheds few cells, has challenging morphology, and/or requires additional ancillary studies.


American Journal of Clinical Pathology | 2006

Biomarkers in Diagnosis of pancreatic carcinoma in fine-needle aspirates.

Nirag Jhala; Darshana Jhala; Selwyn M. Vickers; Isam Eltoum; Surinder K. Batra; Upender Manne; Mohamad A. Eloubeidi; Jennifer J. Jones; William E. Grizzle

This study was undertaken to determine whether recently identified proteins could be translated to clinical practice as markers to distinguish pancreatic adenocarcinoma from chronic pancreatitis on fine-needle aspirate (FNA) samples. Resected pancreatic tissue sections (n = 40) and FNA samples (n = 65) were stained for clusterin-beta, MUC4, survivin, and mesothelin. For each biomarker, the staining patterns in adenocarcinoma and in reactive ductal epithelium were evaluated and compared. Clusterin-beta stained reactive ductal epithelium significantly more frequently than pancreatic adenocarcinoma (P < .001). In comparison, MUC4 and mesothelin were expressed more frequently in pancreatic adenocarcinoma on tissue sections. Positive staining for MUC4 (91% vs 0%; P < .001) and mesothelin (62% vs 0%; P = .01) and absence of staining for clusterin-beta (90% vs 7%; P < .001) were noted significantly more frequently in adenocarcinoma cells than in reactive cells in FNA samples. Clusterin-beta and MUC4 can help distinguish reactive ductal epithelial cells from the cells of pancreatic adenocarcinoma in FNA samples.

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Darshana Jhala

University of Pennsylvania

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Mohamad A. Eloubeidi

University of Alabama at Birmingham

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William E. Grizzle

University of Alabama at Birmingham

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Isam Eltoum

University of Alabama at Birmingham

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Selwyn M. Vickers

University of Alabama at Birmingham

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Upender Manne

University of Alabama at Birmingham

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Gene P. Siegal

University of Alabama at Birmingham

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Venkat R. Katkoori

University of Alabama at Birmingham

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