Kalpaj R Parekh

Dr. Kalpaj R Parekh


Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 2017 in Anesthesiology
Verified
Journal Article
Closed access
EBEmine Ozgur Bayman
Emine Ozgur Bayman
KPKalpaj R Parekh
Kalpaj R Parekh
JKJohn Keech
John Keech
ASAtakan Selte
Atakan Selte
TBTimothy J. Brennan
Timothy J. Brennan
Background: The goal of this study was to detect the predictors of chronic pain at 6 months after thoracic surgery from a comprehensive evaluation of demographic, psychosocial, and surgical factors. Methods: Thoracic surgery patients were enrolled 1 week before surgery and followed up 6 months postsurgery in this prospective, observational study. Comprehensive psychosocial measurements were assessed before surgery. The presence and severity of pain were assessed at 3 and 6 months after surgery. One hundred seven patients were assessed during the first 3 days after surgery, and 99 (30 thoracotomy and 69 video-assisted thoracoscopic surgery, thoracoscopy) patients completed the 6-month follow-up. Patients with versus without chronic pain related to thoracic surgery at 6 months were compared. Results: Both incidence (P = 0.37) and severity (P = 0.97) of surgery-related chronic pain at 6 months were similar after thoracotomy (33%; 95% CI, 17 to 53%; 3.3 ± 2.1) and thoracoscopy (25%; 95% CI, 15 to 36%; 3.3 ± 1.7). Both frequentist and Bayesian multivariate models revealed that the severity of acute pain (numerical rating scale, 0 to 10) is the measure associated with chronic pain related to thoracic surgery. Psychosocial factors and quantitative sensory testing were not predictive. Conclusions: There was no difference in the incidence and severity of chronic pain at 6 months in patients undergoing thoracotomy versus thoracoscopy. Unlike other postsurgical pain conditions, none of the preoperative psychosocial measurements were associated with chronic pain after thoracic surgery.

1 May 2020 in Cell
Verified
Journal Article
Closed access
WRWei Rao
Wei Rao
SWShan Wang
Shan Wang
MDMarcin Duleba
Marcin Duleba
SNSuchan Niroula
Suchan Niroula
KGKristina Goller
Kristina Goller
WXWa Xian
Wa Xian

15 May 2018 in American Journal of Respiratory and Critical Care Medicine
Verified
Journal Article
Closed access
BRBradley H. Rosen
Bradley H. Rosen
TET. Idil Apak Evans
T. Idil Apak Evans
SMShashanna R. Moll
Shashanna R. Moll
JGJaimie S. Gray
Jaimie S. Gray
BLBo Liang
Bo Liang
JEJohn Engelhardt
John Engelhardt
Rationale: Classical interpretation of cystic fibrosis (CF) lung disease pathogenesis suggests that infection initiates disease progression, leading to an exuberant inflammatory response, excessive mucus, and ultimately bronchiectasis. Although symptomatic antibiotic treatment controls lung infections early in disease, lifelong bacterial residence typically ensues. Processes that control the establishment of persistent bacteria in the CF lung, and the contribution of noninfectious components to disease pathogenesis, are poorly understood. Objectives: To evaluate whether continuous antibiotic therapy protects the CF lung from disease using a ferret model that rapidly acquires lethal bacterial lung infections in the absence of antibiotics. Methods: CFTR (cystic fibrosis transmembrane conductance regulator)–knockout ferrets were treated with three antibiotics from birth to several years of age and lung disease was followed by quantitative computed tomography, BAL, and histopathology. Lung disease was compared with CFTR-knockout ferrets treated symptomatically with antibiotics. Measurements and Main Results: Bronchiectasis was quantified from computed tomography images. BAL was evaluated for cellular differential and features of inflammatory cellular activation, bacteria, fungi, and quantitative proteomics. Semiquantitative histopathology was compared across experimental groups. We demonstrate that lifelong antibiotics can protect the CF ferret lung from infections for several years. Surprisingly, CF animals still developed hallmarks of structural bronchiectasis, neutrophil-mediated inflammation, and mucus accumulation, despite the lack of infection. Quantitative proteomics of BAL from CF and non-CF pairs demonstrated a mucoinflammatory signature in the CF lung dominated by Muc5B and neutrophil chemoattractants and products. Conclusions: These findings implicate mucoinflammatory processes in the CF lung as pathogenic in the absence of clinically apparent bacterial and fungal infections.

1 June 2000 in The Journal of Thoracic and Cardiovascular Surgery
Verified
Journal Article
Closed access
VRValerie W. Rusch
Valerie W. Rusch
KPKalpaj R Parekh
Kalpaj R Parekh
LLLarry Leon
Larry Leon
EVEnnapadam Venkatraman
Ennapadam Venkatraman
MBManjit S. Bains
Manjit S. Bains
RGRobert J. Ginsberg
Robert J. Ginsberg

1 March 2014 in American Journal of Respiratory Cell and Molecular Biology
Verified
Journal Article
Closed access
XSXingshen Sun
Xingshen Sun
AOAlicia K. Olivier
Alicia K. Olivier
BLBo Liang
Bo Liang
YYYaling Yi
Yaling Yi
HSHongshu Sui
Hongshu Sui
JEJohn Engelhardt
John Engelhardt
Chronic bacterial lung infections in cystic fibrosis (CF) are caused by defects in the CF transmembrane conductance regulator chloride channel. Previously, we described that newborn CF transmembrane conductance regulator–knockout ferrets rapidly develop lung infections within the first week of life. Here, we report a more slowly progressing lung bacterial colonization phenotype observed in juvenile to adult CF ferrets reared on a layered antibiotic regimen. Even on antibiotics, CF ferrets were still very susceptible to bacterial lung infection. The severity of lung histopathology ranged from mild to severe, and variably included mucus obstruction of the airways and submucosal glands, air trapping, atelectasis, bronchopneumonia, and interstitial pneumonia. In all CF lungs, significant numbers of bacteria were detected and impaired tracheal mucociliary clearance was observed. Although Streptococcus, Staphylococcus, and Enterococcus were observed most frequently in the lungs of CF animals, each animal displayed a predominant bacterial species that accounted for over 50% of the culturable bacteria, with no one bacterial taxon predominating in all animals. Matrix-assisted laser desorption–ionization time-of-flight mass spectrometry fingerprinting was used to quantify lung bacteria in 10 CF animals and demonstrated Streptococcus, Staphylococcus, Enterococcus, or Escherichia as the most abundant genera. Interestingly, there was significant overlap in the types of bacteria observed in the lung and intestine of a given CF animal, including bacterial taxa unique to the lung and gut of each CF animal analyzed. These findings demonstrate that CF ferrets develop lung disease during the juvenile and adult stages that is similar to patients with CF, and suggest that enteric bacterial flora may seed the lung of CF ferrets.

6 June 2011 in Proceedings of the National Academy of Sciences
Verified
Journal Article
Open access
PDF file
OIOmar A. Itani
Omar A. Itani
CJChen Jeng-Haur
Chen Jeng-Haur
PKPhilip H. Karp
Philip H. Karp
SESarah Ernst
Sarah Ernst
SKShaf Keshavjee
Shaf Keshavjee
MWMichael J. Welsh
Michael J. Welsh
Loss of cystic fibrosis transmembrane conductance regulator (CFTR) anion channel function causes cystic fibrosis (CF) lung disease. CFTR is expressed in airway epithelia, but how CF alters electrolyte transport across airway epithelia has remained uncertain. Recent studies of a porcine model showed that in vivo, excised, and cultured CFTR −/− and CFTR ΔF508/ΔF508 airway epithelia lacked anion conductance, and they did not hyperabsorb Na + . Therefore, we asked whether Cl − and Na + conductances were altered in human CF airway epithelia. We studied differentiated primary cultures of tracheal/bronchial epithelia and found that transepithelial conductance (Gt) under basal conditions and the cAMP-stimulated increase in Gt were markedly attenuated in CF epithelia compared with non-CF epithelia. These data reflect loss of the CFTR anion conductance. In CF and non-CF epithelia, the Na + channel inhibitor amiloride produced similar reductions in Gt and Na + absorption, indicating that Na + conductance in CF epithelia did not exceed that in non-CF epithelia. Consistent with previous reports, adding amiloride caused greater reductions in transepithelial voltage and short-circuit current in CF epithelia than in non-CF epithelia; these changes are attributed to loss of a Cl − conductance. These results indicate that Na + conductance was not increased in these cultured CF tracheal/bronchial epithelia and point to loss of anion transport as key to airway epithelial dysfunction in CF.