31 results on '"Jae Hyung Chang"'
Search Results
2. Critical role of neutralizing antibody for SARS-CoV-2 reinfection and transmission
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Young-Il Kim, Se-Mi Kim, Su-Jin Park, Eun-Ha Kim, Kwang-Min Yu, Jae-Hyung Chang, Eun Ji Kim, Mark Anthony B. Casel, Rare Rollon, Seung-Gyu Jang, Jihye Um, Min-Suk Song, Hye Won Jeong, Eung-Gook Kim, Yeonjae Kim, So Yeon Kim, Jun-Sun Park, Mi Sun Park, Geun-Yong Kwon, Sang Gu Yeo, Shin-Ae Lee, Youn Jung Choi, Jae U. Jung, and Young Ki Choi
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SARS-CoV-2 ,reinfection ,COVID-19 ,neutralizing antibody ,ferret model ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
Cases of laboratory-confirmed SARS-CoV-2 reinfection have been reported in a number of countries. Further, the level of natural immunity induced by SARS-CoV-2 infection is not fully clear, nor is it clear if a primary infection is protective against reinfection. To investigate the potential association between serum antibody titres and reinfection of SARS-CoV-2, ferrets with different levels of NAb titres after primary SARS-CoV-2 infection were subjected to reinfection with a heterologous SARS-CoV-2 strain. All heterologous SARS-CoV-2 reinfected ferrets showed active virus replication in the upper respiratory and gastro-intestinal tracts. However, the high NAb titre group showed attenuated viral replication and rapid viral clearance. In addition, direct-contact transmission was observed only from reinfected ferrets with low NAb titres (
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- 2021
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3. A vesicular stomatitis virus-based prime-boost vaccination strategy induces potent and protective neutralizing antibodies against SARS-CoV-2.
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Gyoung Nyoun Kim, Jung-Ah Choi, Kunyu Wu, Nasrin Saeedian, Eunji Yang, Hayan Park, Sun-Je Woo, Gippeum Lim, Seong-Gyu Kim, Su-Kyeong Eo, Hoe Won Jeong, Taewoo Kim, Jae-Hyung Chang, Sang Hwan Seo, Na Hyung Kim, Eunsil Choi, Seungho Choo, Sangkyun Lee, Andrew Winterborn, Yue Li, Kate Parham, Justin M Donovan, Brock Fenton, Jimmy D Dikeakos, Gregory A Dekaban, S M Mansour Haeryfar, Ryan M Troyer, Eric J Arts, Stephen D Barr, Manki Song, and C Yong Kang
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
The development of safe and effective vaccines to prevent SARS-CoV-2 infections remains an urgent priority worldwide. We have used a recombinant vesicular stomatitis virus (rVSV)-based prime-boost immunization strategy to develop an effective COVID-19 vaccine candidate. We have constructed VSV genomes carrying exogenous genes resulting in the production of avirulent rVSV carrying the full-length spike protein (SF), the S1 subunit, or the receptor-binding domain (RBD) plus envelope (E) protein of SARS-CoV-2. Adding the honeybee melittin signal peptide (msp) to the N-terminus enhanced the protein expression, and adding the VSV G protein transmembrane domain and the cytoplasmic tail (Gtc) enhanced protein incorporation into pseudotype VSV. All rVSVs expressed three different forms of SARS-CoV-2 spike proteins, but chimeras with VSV-Gtc demonstrated the highest rVSV-associated expression. In immunized mice, rVSV with chimeric S protein-Gtc derivatives induced the highest level of potent neutralizing antibodies and T cell responses, and rVSV harboring the full-length msp-SF-Gtc proved to be the superior immunogen. More importantly, rVSV-msp-SF-Gtc vaccinated animals were completely protected from a subsequent SARS-CoV-2 challenge. Overall, we have developed an efficient strategy to induce a protective response in SARS-CoV-2 challenged immunized mice. Vaccination with our rVSV-based vector may be an effective solution in the global fight against COVID-19.
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- 2021
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4. Antiviral Efficacies of FDA-Approved Drugs against SARS-CoV-2 Infection in Ferrets
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Su-Jin Park, Kwang-Min Yu, Young-Il Kim, Se-Mi Kim, Eun-Ha Kim, Seong-Gyu Kim, Eun Ji Kim, Mark Anthony B. Casel, Rare Rollon, Seung-Gyu Jang, Min-Hyeok Lee, Jae-Hyung Chang, Min-Suk Song, Hye Won Jeong, Younho Choi, Weiqiang Chen, Woo-Jin Shin, Jae U. Jung, and Young Ki Choi
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COVID-19 ,severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,antiviral therapeutics ,immunosuppression ,serum neutralization ,ferrets ,Microbiology ,QR1-502 - Abstract
ABSTRACT Due to the urgent need of a therapeutic treatment for coronavirus (CoV) disease 2019 (COVID-19) patients, a number of FDA-approved/repurposed drugs have been suggested as antiviral candidates at clinics, without sufficient information. Furthermore, there have been extensive debates over antiviral candidates for their effectiveness and safety against severe acute respiratory syndrome CoV 2 (SARS-CoV-2), suggesting that rapid preclinical animal studies are required to identify potential antiviral candidates for human trials. To this end, the antiviral efficacies of lopinavir-ritonavir, hydroxychloroquine sulfate, and emtricitabine-tenofovir for SARS-CoV-2 infection were assessed in the ferret infection model. While the lopinavir-ritonavir-, hydroxychloroquine sulfate-, or emtricitabine-tenofovir-treated group exhibited lower overall clinical scores than the phosphate-buffered saline (PBS)-treated control group, the virus titers in nasal washes, stool specimens, and respiratory tissues were similar between all three antiviral-candidate-treated groups and the PBS-treated control group. Only the emtricitabine-tenofovir-treated group showed lower virus titers in nasal washes at 8 days postinfection (dpi) than the PBS-treated control group. To further explore the effect of immune suppression on viral infection and clinical outcome, ferrets were treated with azathioprine, an immunosuppressive drug. Compared to the PBS-treated control group, azathioprine-immunosuppressed ferrets exhibited a longer period of clinical illness, higher virus titers in nasal turbinate, delayed virus clearance, and significantly lower serum neutralization (SN) antibody titers. Taken together, all antiviral drugs tested marginally reduced the overall clinical scores of infected ferrets but did not significantly affect in vivo virus titers. Despite the potential discrepancy of drug efficacies between animals and humans, these preclinical ferret data should be highly informative to future therapeutic treatment of COVID-19 patients. IMPORTANCE The SARS-CoV-2 pandemic continues to spread worldwide, with rapidly increasing numbers of mortalities, placing increasing strain on health care systems. Despite serious public health concerns, no effective vaccines or therapeutics have been approved by regulatory agencies. In this study, we tested the FDA-approved drugs lopinavir-ritonavir, hydroxychloroquine sulfate, and emtricitabine-tenofovir against SARS-CoV-2 infection in a highly susceptible ferret infection model. While most of the drug treatments marginally reduced clinical symptoms, they did not reduce virus titers, with the exception of emtricitabine-tenofovir treatment, which led to diminished virus titers in nasal washes at 8 dpi. Further, the azathioprine-treated immunosuppressed ferrets showed delayed virus clearance and low SN titers, resulting in a prolonged infection. As several FDA-approved or repurposed drugs are being tested as antiviral candidates at clinics without sufficient information, rapid preclinical animal studies should proceed to identify therapeutic drug candidates with strong antiviral potential and high safety prior to a human efficacy trial.
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- 2020
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5. Postvaccine Anti–SARS-CoV-2 Spike Protein Antibody Development in Kidney Transplant Recipients
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Syed Ali Husain, Demetra Tsapepas, Kathryn F. Paget, Jae-Hyung Chang, R. John Crew, Geoffrey K. Dube, Hilda E. Fernandez, Heather K. Morris, Sumit Mohan, and David J. Cohen
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Diseases of the genitourinary system. Urology ,RC870-923 - Published
- 2021
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6. Obesity and kidney transplantation
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Jae-Hyung Chang, Vladimir Mushailov, and Sumit Mohan
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Transplantation ,Immunology and Allergy - Published
- 2023
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7. Home Care Delivery and Remote Patient Monitoring of Kidney Transplant Recipients During COVID-19 Pandemic
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Kevin Schmitt, Jae-Hyung Chang, R. John Crew, Sharlinee Sritharan, Shefali Patel, and Demetra Tsapepas
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Transplantation ,Telemedicine ,Coronavirus disease 2019 (COVID-19) ,SARS-CoV-2 ,business.industry ,Remote patient monitoring ,Vital signs ,COVID-19 ,Telehealth ,medicine.disease ,Home Care Services ,Kidney Transplantation ,Blood pressure ,Health care ,Pandemic ,Humans ,Medicine ,Medical emergency ,business ,Delivery of Health Care ,Pandemics ,Monitoring, Physiologic - Abstract
Telehealth plays a critical role in the response of healthcare organizations during the COVID-19 pandemic. While telemedicine offers a real-time patient-provider encounter, the inability to obtain vital signs during virtual visits is a potential limitation. Remote patient monitoring (RPM) uses portable devices in the patient‘s home to collect and electronically transmit physiological data to clinicians. Two kidney transplant recipients were enrolled in RPM in their immediate post-transplant period. Real-time monitoring of their physiological data at home through the RPM in combination with the ability to titrate medications resulted in normalization of the blood pressure and blood glucose measurements by six weeks. Our initial experience demonstrates that RPM is feasible and effective in the post-transplant period and can expand care opportunities on the remote care model. This is more relevant than ever as remote monitoring can facilitate the care of COVID-19-positive transplant patients who require close monitoring while isolated at home.
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- 2021
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8. Reversal of Donor Hepatitis C Virus–Related Mesangial Proliferative GN in a Kidney Transplant Recipient
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Lloyd E. Ratner, Pascale Khairallah, Jai Radhakrishnan, Satoru Kudose, Jae-Hyung Chang, Heather Morris, and Sumit Mohan
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Hepatitis ,business.industry ,Hepatitis C virus ,Glomerulonephritis ,General Medicine ,medicine.disease ,medicine.disease_cause ,Research Letters ,Kidney transplant recipient ,Nephrology ,Immunology ,medicine ,business ,Kidney transplantation - Published
- 2020
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9. Disaster Response to the COVID-19 Pandemic for Patients with Kidney Disease in New York City
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Pietro A. Canetta, Irina Y. Baramidze, Krzysztof Kiryluk, Sean Kalloo, Syeda B. Ahmad, Bessie N. Craig, Maya K. Rao, Jason Zheng, Jonathan Barasch, Jane Akomeah, Syed A. Husain, Vaqar H. Shah, Gail Williams, Jordann Lewis, Robin Ferrer, Maria M. Morban, Shayan Shirazian, Andrew S. Bomback, Andrew A. Moses, Meeran Lee, Jacob S. Stevens, Piotr Starakiewicz, Andrew Beenken, Bradley Nelson, Qais Al-Awqati, Allyson R. Medina, Maddalena Marasa, Vanna M. Nicasio, Stacy Piva, Emily Daniel, Iman Azam Ghavami, Karla Mehl, Geoffrey K. Dube, Simone Sanna-Cherchi, Rosemary V. Sampogna, Bruno Lovisi, Hilda Fernandez, Anthony M. Valeri, Maria Alejandra Aponte, David J. Cohen, Jung Soo Kim, Katherine Toma, Kathryn Paget, Hector Alvarado Verduzco, Sumit Mohan, Jai Radhakrishnan, Eric Siddall, Pascale Khairallah, Jordan G. Nestor, Nisha Clement, Denzil Douglas, Heather Morris, Gerald B. Appel, Ali G. Gharavi, Yonatan Peleg, Donald W. Landry, Wooin Ahn, Daisy Mathew, Russell J. Crew, Jae Hyung Chang, and Tom Nickolas
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Male ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,Pneumonia, Viral ,Disaster Planning ,Disasters ,Betacoronavirus ,Renal Dialysis ,Outcome Assessment, Health Care ,Pandemic ,Humans ,Medicine ,Renal Insufficiency, Chronic ,Pandemics ,Patient Care Team ,Academic Medical Centers ,SARS-CoV-2 ,business.industry ,COVID-19 ,General Medicine ,medicine.disease ,Disaster response ,Kidney Transplantation ,Nephrology ,Perspective ,Emergency medicine ,Female ,New York City ,Coronavirus Infections ,business ,Kidney disease - Published
- 2020
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10. Donor-derived cell-free DNA and renal allograft rejection in surveillance biopsies and indication biopsies
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Jae‐Hyung Chang, Hector Alvarado Verduzco, Katherine Toma, Sharlinee Sritharan, Sumit Mohan, and Syed Ali Husain
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Graft Rejection ,Transplantation ,Cross-Sectional Studies ,Biopsy ,Humans ,Allografts ,Kidney ,Cell-Free Nucleic Acids ,Kidney Transplantation ,Tissue Donors ,Retrospective Studies - Abstract
To evaluate the role of circulating dd-cfDNA in allograft surveillance in immunologically high-risk patients, a retrospective cross-sectional study of 261 kidney transplant recipients who underwent outpatient allograft biopsy at our center between September 2020 and August 2021 was performed. Of the 236 dd-cfDNA results included, 37 samples were obtained at the time of a surveillance biopsy in sensitized recipients and 199 at the time of a clinically indicated biopsy. The median serum creatinine at the time of the biopsy was 1.3 mg/dl and 2.1 mg/dl for surveillance biopsies and clinically indicated biopsies, respectively (P .001). Rejection was diagnosed in 27% of surveillance biopsies and 29% of clinically indicated biopsies. Among surveillance biopsies, sensitivity and specificity to detect rejection were 0% and 89%, respectively, and among clinically indicated biopsies they were 28% and 96%, respectively. The sensitivity and specificity to detect antibody-mediated rejection were 0% and 91% among surveillance biopsies and 50% and 94% among clinically indicated biopsies. Nine biopsies without rejection findings had corresponding dd-cfDNA of ≥1%. Our data does not support dd-cfDNA as a biomarker for kidney allograft rejection, even in immunologically high-risk patients in the absence of graft dysfunction.
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- 2021
11. Considerations for utilizing medullary sponge kidney allografts in pediatric patients
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Christina Carpenter, Lloyd E. Ratner, Natalie S Uy, Ruchi Mahajan, Brian Runge, Namrata G. Jain, Jae-Hyung Chang, and Pedro Rodrigo Sandoval
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Transplantation ,education.field_of_study ,medicine.medical_specialty ,business.industry ,Urinary system ,medicine.medical_treatment ,Population ,030232 urology & nephrology ,Stent ,Disease ,030230 surgery ,Medullary sponge kidney ,medicine.disease ,Living donor ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Pediatrics, Perinatology and Child Health ,medicine ,Risks and benefits ,education ,business ,Hydronephrosis - Abstract
Background Medullary sponge kidney (MSK) disease predisposes patients to recurrent nephrolithiasis, which affects one in every 5000 people in the United States. Methods We report a rare case of a pediatric recipient of a living donor MSK transplant and discuss considerations when discussing risks and benefits of accepting MSK allografts for this population. Results The recipient was admitted due to concerns for nephrolithiasis, hydronephrosis, and urinary tract infection at 1-month post-transplant. The hydronephrosis was resolved by surgical removal of an encrusted ureteral stent; this was followed by supplementation with oral medications to prevent future episodes of nephrolithiasis. The recipient did not have any further episodes after this as seen at a 1-year follow-up. The donor has remained well through this period. Conclusions With increasing organ shortages, the use of variety of donors may need to be considered to enlarge the organ pool.
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- 2021
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12. Telehealth in outpatient management of kidney transplant recipients during COVID‐19 pandemic in New York
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R. John Crew, Yvonne L. Burgos, David J. Cohen, Heather Morris, Jae-Hyung Chang, Demetra Tsapepas, Geoffrey K. Dube, Daryle M. Blackstock, S. Ali Husain, Mohammed Diop, Sumit Mohan, and Hilda Fernandez
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Adult ,Male ,Coronavirus disease 2019 (COVID-19) ,Physical Distancing ,MEDLINE ,Telehealth ,030230 surgery ,Kidney transplant ,03 medical and health sciences ,0302 clinical medicine ,Pandemic ,Health care ,Ambulatory Care ,Humans ,Medicine ,Pandemics ,Aged ,Aged, 80 and over ,Postoperative Care ,Transplantation ,business.industry ,COVID-19 ,Middle Aged ,medicine.disease ,Kidney Transplantation ,Metropolitan area ,Telemedicine ,Outcome and Process Assessment, Health Care ,Ambulatory ,Female ,New York City ,030211 gastroenterology & hepatology ,Medical emergency ,business - Abstract
The New York metropolitan region was an early epicenter of the COVID-19 pandemic. The New York State stay-at-home order forced hospitals and health care providers to rethink care algorithms as in-person visits became infeasible or unsafe. In response to the COVID-19 pandemic, the kidney transplant program at Columbia University Irving Medical Center rapidly implemented a telehealth program that offers virtual visits for ambulatory patients.
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- 2020
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13. KIM-1 mediates fatty acid uptake by renal tubular cells to promote progressive diabetic kidney disease
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Huiping Zhao, Jiahua Li, Julie Hawkins, Seiji Kishi, Venkata S. Sabbisetti, Li Li, Sheng Xiao, Craig R. Brooks, Heung-Myong Woo, Takaharu Ichimura, Vijay K. Kuchroo, Shan Mou, Jae-Hyung Chang, Suetonia C. Palmer, Joel M. Henderson, Pierre Galichon, Yutaro Mori, Amrendra Kumar Ajay, and Joseph V. Bonventre
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0301 basic medicine ,Male ,medicine.medical_specialty ,Physiology ,Palmitic Acid ,Article ,Diabetes Mellitus, Experimental ,Diabetic nephropathy ,Kidney Tubules, Proximal ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Fibrosis ,Internal medicine ,Diabetes mellitus ,medicine ,Renal fibrosis ,Animals ,Humans ,Diabetic Nephropathies ,Hepatitis A Virus Cellular Receptor 1 ,Sulfones ,RNA, Small Interfering ,Molecular Biology ,Mice, Inbred BALB C ,business.industry ,Fatty Acids ,Glomerulosclerosis ,Serum Albumin, Bovine ,Cell Biology ,Cell Cycle Checkpoints ,medicine.disease ,Streptozotocin ,Endocytosis ,Mice, Inbred C57BL ,030104 developmental biology ,Endocrinology ,Benzamides ,Albuminuria ,RNA Interference ,medicine.symptom ,business ,Tubulointerstitial Disease ,030217 neurology & neurosurgery ,medicine.drug ,DNA Damage - Abstract
Summary Tubulointerstitial abnormalities are predictive of the progression of diabetic kidney disease (DKD), and their targeting may be an effective means for prevention. Proximal tubular (PT) expression of kidney injury molecule (KIM)-1, as well as blood and urinary levels, are increased early in human diabetes and can predict the rate of disease progression. Here, we report that KIM-1 mediates PT uptake of palmitic acid (PA)-bound albumin, leading to enhanced tubule injury with DNA damage, PT cell-cycle arrest, interstitial inflammation and fibrosis, and secondary glomerulosclerosis. Such injury can be ameliorated by genetic ablation of the KIM-1 mucin domain in a high-fat-fed streptozotocin mouse model of DKD. We also identified TW-37 as a small molecule inhibitor of KIM-1-mediated PA-albumin uptake and showed in vivo in a kidney injury model in mice that it ameliorates renal inflammation and fibrosis. Together, our findings support KIM-1 as a new therapeutic target for DKD.
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- 2020
14. Early Outcomes of Outpatient Management of Kidney Transplant Recipients with Coronavirus Disease 2019
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Hilda Fernandez, Olga Pawliczak, Kathryn Paget, Geoffrey K. Dube, S. Ali Husain, Demetra Tsapepas, Sumit Mohan, R. John Crew, David J. Cohen, Sharlinee Sritharan, Heather Morris, Mia Boehler, Jae Hyung Chang, and Shefali Patel
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medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,Epidemiology ,030232 urology & nephrology ,030230 surgery ,Critical Care and Intensive Care Medicine ,medicine.disease_cause ,Kidney transplant ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Outpatients ,medicine ,Humans ,Pandemics ,Kidney transplantation ,Coronavirus ,Transplantation ,Creatinine ,business.industry ,SARS-CoV-2 ,COVID-19 ,Original Articles ,medicine.disease ,Kidney Transplantation ,chemistry ,Nephrology ,Cohort ,Outpatient management ,business ,Cohort study - Abstract
Background and objectives Outcomes of kidney transplant recipients diagnosed with coronavirus disease 2019 as outpatients have not been described. Design, setting, participants, & measurements We obtained clinical data for 41 consecutive outpatient kidney transplant recipients with known or suspected coronavirus disease 2019. Chi-squared and Wilcoxon rank sum tests were used to compare characteristics of patients who required hospitalization versus those who did not. Results Of 41 patients, 22 (54%) had confirmed coronavirus disease 2019, and 19 (46%) were suspected cases. Patients most commonly reported fever (80%), cough (56%), and dyspnea (39%). At the end of follow-up, 13 patients (32%) required hospitalization a median of 8 days (range, 1–16) after symptom onset, and 23 (56%) had outpatient symptom resolution a median of 12 days (4–23) after onset. Patients who required hospitalization were more likely to have reported dyspnea (77% versus 21%, P=0.003) and had higher baseline creatinine (median, 2.0 versus 1.3 mg/dl, P=0.02), but there were no other differences between groups. Conclusions In an early cohort of outpatient kidney transplant recipients with known or suspected coronavirus disease 2019, many had symptomatic resolution without requiring hospitalization.
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- 2020
15. Antiviral Efficacies of FDA-Approved Drugs against SARS-CoV-2 Infection in Ferrets
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Jae Hyung Chang, Jae U. Jung, Hye Won Jeong, Younho Choi, Eun-Ha Kim, Young-Il Kim, Seong Gyu Kim, Seung Gyu Jang, Mark Anthony B. Casel, Rare Rollon, Young Ki Choi, Min-Suk Song, Min Hyeok Lee, Eun Ji Kim, Woo Jin Shin, Kwang-Min Yu, Weiqiang Chen, Su-Jin Park, and Se Mi Kim
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medicine.medical_treatment ,Pneumonia, Viral ,Antibodies, Viral ,medicine.disease_cause ,Antiviral Agents ,Microbiology ,Virus ,Betacoronavirus ,03 medical and health sciences ,In vivo ,Virology ,medicine ,Animals ,Humans ,Pandemics ,030304 developmental biology ,Coronavirus ,Hydroxychloroquine Sulfate ,0303 health sciences ,immunosuppression ,SARS-CoV-2 ,United States Food and Drug Administration ,030306 microbiology ,business.industry ,Antibody titer ,virus diseases ,Hydroxychloroquine ,Viral Load ,Therapeutics and Prevention ,antiviral therapeutics ,serum neutralization ,Antibodies, Neutralizing ,United States ,QR1-502 ,Disease Models, Animal ,Immunosuppressive drug ,covid-19 ,Immunology ,Female ,severe acute respiratory syndrome coronavirus 2 (sars-cov-2) ,Coronavirus Infections ,business ,Viral load ,ferrets ,Research Article ,medicine.drug - Abstract
The SARS-CoV-2 pandemic continues to spread worldwide, with rapidly increasing numbers of mortalities, placing increasing strain on health care systems. Despite serious public health concerns, no effective vaccines or therapeutics have been approved by regulatory agencies. In this study, we tested the FDA-approved drugs lopinavir-ritonavir, hydroxychloroquine sulfate, and emtricitabine-tenofovir against SARS-CoV-2 infection in a highly susceptible ferret infection model. While most of the drug treatments marginally reduced clinical symptoms, they did not reduce virus titers, with the exception of emtricitabine-tenofovir treatment, which led to diminished virus titers in nasal washes at 8 dpi. Further, the azathioprine-treated immunosuppressed ferrets showed delayed virus clearance and low SN titers, resulting in a prolonged infection. As several FDA-approved or repurposed drugs are being tested as antiviral candidates at clinics without sufficient information, rapid preclinical animal studies should proceed to identify therapeutic drug candidates with strong antiviral potential and high safety prior to a human efficacy trial., Due to the urgent need of a therapeutic treatment for coronavirus (CoV) disease 2019 (COVID-19) patients, a number of FDA-approved/repurposed drugs have been suggested as antiviral candidates at clinics, without sufficient information. Furthermore, there have been extensive debates over antiviral candidates for their effectiveness and safety against severe acute respiratory syndrome CoV 2 (SARS-CoV-2), suggesting that rapid preclinical animal studies are required to identify potential antiviral candidates for human trials. To this end, the antiviral efficacies of lopinavir-ritonavir, hydroxychloroquine sulfate, and emtricitabine-tenofovir for SARS-CoV-2 infection were assessed in the ferret infection model. While the lopinavir-ritonavir-, hydroxychloroquine sulfate-, or emtricitabine-tenofovir-treated group exhibited lower overall clinical scores than the phosphate-buffered saline (PBS)-treated control group, the virus titers in nasal washes, stool specimens, and respiratory tissues were similar between all three antiviral-candidate-treated groups and the PBS-treated control group. Only the emtricitabine-tenofovir-treated group showed lower virus titers in nasal washes at 8 days postinfection (dpi) than the PBS-treated control group. To further explore the effect of immune suppression on viral infection and clinical outcome, ferrets were treated with azathioprine, an immunosuppressive drug. Compared to the PBS-treated control group, azathioprine-immunosuppressed ferrets exhibited a longer period of clinical illness, higher virus titers in nasal turbinate, delayed virus clearance, and significantly lower serum neutralization (SN) antibody titers. Taken together, all antiviral drugs tested marginally reduced the overall clinical scores of infected ferrets but did not significantly affect in vivo virus titers. Despite the potential discrepancy of drug efficacies between animals and humans, these preclinical ferret data should be highly informative to future therapeutic treatment of COVID-19 patients.
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- 2020
16. Diabetic kidney disease in FVB/NJ Akita mice: temporal pattern of kidney injury and urinary nephrin excretion.
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Jae-Hyung Chang, Seung-Yeol Paik, Lan Mao, William Eisner, Patrick J Flannery, Liming Wang, Yuping Tang, Natalie Mattocks, Samy Hadjadj, Jean-Michel Goujon, Phillip Ruiz, Susan B Gurley, and Robert F Spurney
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Medicine ,Science - Abstract
Akita mice are a genetic model of type 1 diabetes. In the present studies, we investigated the phenotype of Akita mice on the FVB/NJ background and examined urinary nephrin excretion as a marker of kidney injury. Male Akita mice were compared with non-diabetic controls for functional and structural characteristics of renal and cardiac disease. Podocyte number and apoptosis as well as urinary nephrin excretion were determined in both groups. Male FVB/NJ Akita mice developed sustained hyperglycemia and albuminuria by 4 and 8 weeks of age, respectively. These abnormalities were accompanied by a significant increase in systolic blood pressure in 10-week old Akita mice, which was associated with functional, structural and molecular characteristics of cardiac hypertrophy. By 20 weeks of age, Akita mice developed a 10-fold increase in albuminuria, renal and glomerular hypertrophy and a decrease in the number of podocytes. Mild-to-moderate glomerular mesangial expansion was observed in Akita mice at 30 weeks of age. In 4-week old Akita mice, the onset of hyperglycemia was accompanied by increased podocyte apoptosis and enhanced excretion of nephrin in urine before the development of albuminuria. Urinary nephrin excretion was also significantly increased in albuminuric Akita mice at 16 and 20 weeks of age and correlated with the albumin excretion rate. These data suggest that: 1. FVB/NJ Akita mice have phenotypic characteristics that may be useful for studying the mechanisms of kidney and cardiac injury in diabetes, and 2. Enhanced urinary nephrin excretion is associated with kidney injury in FVB/NJ Akita mice and is detectable early in the disease process.
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- 2012
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17. Analysis of dendritic cells and ischemia-reperfusion changes in postimplantation renal allograft biopsies may serve as predictors of subsequent rejection episodes
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Vivette D. D'Agati, Lloyd E. Ratner, Govind Bhagat, Glen S. Markowitz, M. A. Hardy, Elena-Rodica Vasilescu, Russel J. Crew, Geo Serban, Ibrahim Batal, Anil Chandraker, Syed A. Husain, Shefali Patel, Demetra Tsapepas, Kasi McCune, Sacha A. De Serres, Sumit Mohan, Jan M. Herter, and Jae-Hyung Chang
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Adult ,Graft Rejection ,Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Time Factors ,Myeloid ,Biopsy ,Ischemia ,Kidney ,Risk Assessment ,Antigens, CD1 ,Young Adult ,03 medical and health sciences ,Cell Movement ,Predictive Value of Tests ,Risk Factors ,Cause of Death ,Living Donors ,medicine ,Humans ,Acute tubular necrosis ,Aged ,Glycoproteins ,Retrospective Studies ,Cause of death ,business.industry ,Immunogenicity ,Graft Survival ,Alloimmunity ,Dendritic Cells ,Dendritic cell ,Middle Aged ,Allografts ,medicine.disease ,Kidney Transplantation ,Tissue Donors ,Treatment Outcome ,030104 developmental biology ,medicine.anatomical_structure ,Nephrology ,Reperfusion Injury ,Female ,business ,Biomarkers - Abstract
Ischemia-reperfusion injury increases allograft immunogenicity and enhances myeloid dendritic cell maturation and trafficking to recipient's secondary lymphoid tissue. Here, we used postreperfusion biopsies from patients who received kidney allografts from deceased donors between 2006 and 2009 to assess the impact of ischemia-reperfusion damage and myeloid dendritic cell density on subsequent allograft rejection episodes. Histologic changes of severe ischemia-reperfusion damage in postreperfusion biopsies were found to be associated with subsequent rejection episodes and suboptimal allograft survival. Using BDCA-1 as a marker of myeloid dendritic cells, postreperfusion biopsies from deceased donors had lower dendritic cell density compared to postreperfusion biopsies from living donors or normal controls. This suggests a rapid emigration of donor dendritic cells out of the allograft. In our cohort, low dendritic cell density was associated with a subsequent increase in rejection episodes. However, it appears that the donor's cause of death also influenced dendritic cell density. Therefore, we assessed the additive impact of severe ischemia-reperfusion changes and low dendritic cell density on subsequent rejection. The aforementioned combination was a powerful and independent predictor of allograft rejection. Thus, our data highlight the prognostic value of histopathologic changes associated with ischemia-reperfusion in postreperfusion biopsies and suggest a rapid posttransplant emigration of myeloid dendritic cells out of the allograft to enhance alloimmunity. These findings may provide a rationale for minimizing ischemia-reperfusion injury and therapeutic targeting of donor-derived dendritic cells to promote rejection-free allograft survival.
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- 2018
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18. Searching for Second Hits for the Development of APOL1-Associated Kidney Disease
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S. Ali Husain and Jae-Hyung Chang
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Nephrology ,business.industry ,Commentary ,Medicine ,business ,medicine.disease ,Bioinformatics ,Kidney disease - Published
- 2019
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19. KIM-1 Mediated Tubular Fatty Acid Uptake Leads to Progressive Diabetic Kidney Disease
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Jiahua Li, Shan Mou, Pierre Galichon, Yutaro Mori, Sheng Xiao, Venkata S. Sabbisetti, Jae-Hyung Chang, Suetonia C. Palmer, Takaharu Ichimura, Vijay K. Kuchroo, Amrendra Kumar Ajay, Li Li, Joseph V. Bonventre, Joel M. Henderson, Heung-Myong Woo, Seiji Kishi, Craig R. Brooks, and Huiping Zhao
- Subjects
chemistry.chemical_classification ,medicine.medical_specialty ,Kidney ,Urinary system ,Mucin ,Albumin ,Fatty acid ,medicine.disease ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Fibrosis ,Internal medicine ,Diabetes mellitus ,medicine ,Renal fibrosis - Abstract
Tubulointerstitial abnormalities are predictive of progression of diabetic kidney disease (DKD) . Proximal tubular (PT) kidney injury molecule (KIM)-1 expression and blood and urinary KIM-1 levels are increased early in human diabetes and can predict rate of progression of disease. We report that KIM-1 mediates PT uptake of fatty acids (FAs) bound to albumin leading to enhanced tubule injury with DNA damage, PT cell cycle arrest, interstitial inflammation and fibrosis, and secondary glomerulosclerosis. Injury is ameliorated by inhibition of uptake by genetic ablation of KIM-1 mucin domain or a newly discovered small molecule inhibitor of KIM-1-mediated FA uptake, TW-37. Our findings support KIM-1 as a new therapeutic target for DKD.
- Published
- 2020
- Full Text
- View/download PDF
20. Knockout of TRPC6 promotes insulin resistance and exacerbates glomerular injury in Akita mice
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Robert F. Spurney, Anne F. Buckley, Liming Wang, and Jae-Hyung Chang
- Subjects
0301 basic medicine ,Blood Glucose ,medicine.medical_specialty ,endocrine system diseases ,medicine.medical_treatment ,030232 urology & nephrology ,Apoptosis ,MAP Kinase Kinase Kinase 5 ,Article ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Insulin resistance ,Downregulation and upregulation ,Internal medicine ,medicine ,TRPC6 Cation Channel ,Animals ,Humans ,Diabetic Nephropathies ,Protein kinase B ,TRPC Cation Channels ,Mice, Knockout ,Type 1 diabetes ,biology ,business.industry ,Podocytes ,Insulin ,medicine.disease ,IRS2 ,Glomerular Mesangium ,Insulin receptor ,Disease Models, Animal ,030104 developmental biology ,Endocrinology ,Diabetes Mellitus, Type 1 ,Nephrology ,Knockout mouse ,biology.protein ,Insulin Receptor Substrate Proteins ,Insulin Resistance ,business - Abstract
Gain-of-function mutations in TRPC6 cause familial focal segmental glomerulosclerosis, and TRPC6 is upregulated in glomerular diseases including diabetic kidney disease. We studied the effect of systemic TRPC6 knockout in the Akita model of type 1 diabetes. Knockout of TRPC6 inhibited albuminuria in Akita mice at 12 and 16 weeks of age, but this difference disappeared by 20 weeks. Knockout of TRPC6 also reduced tubular injury in Akita mice; however, mesangial expansion was significantly increased. Hyperglycemia and blood pressure were similar between TRPC6 knockout and wild-type Akita mice, but knockout mice were more insulin resistant. In cultured podocytes, knockout of TRPC6 inhibited expression of the calcium/calcineurin responsive gene insulin receptor substrate 2 and decreased insulin responsiveness. Insulin resistance is reported to promote diabetic kidney disease independent of blood glucose levels. While the mechanisms are not fully understood, insulin activates both Akt2 and ERK, which inhibits apoptosis signal regulated kinase 1 (ASK1)-p38–induced apoptosis. In cultured podocytes, hyperglycemia stimulated p38 signaling and induced apoptosis, which was reduced by insulin and ASK1 inhibition and enhanced by Akt or ERK inhibition. Glomerular p38 signaling was increased in TRPC6 knockout Akita mice and was associated with enhanced expression of the p38 gene target cyclooxygenase 2. These data suggest that knockout of TRPC6 in Akita mice promotes insulin resistance and exacerbates glomerular disease independent of hyperglycemia.
- Published
- 2019
21. Infection and Rapid Transmission of SARS-CoV-2 in Ferrets
- Author
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Van Dam Lai, Jae U. Jung, Haryoung Poo, Jae Hyung Chang, Eun-Ha Kim, Se Mi Kim, Young Ki Choi, Min-Suk Song, Hye Won Jeong, Mark Anthony B. Casel, Seung-Hun Lee, Kwang-Min Yu, Jihye Um, Jun Sun Park, Richard J. Webby, Suan-Sin Foo, Seong Gyu Kim, Bum Sik Chin, Yeonjae Kim, Su-Jin Park, Young-Il Kim, Ok Jun Lee, Eun Ji Kim, Ki Hyun Chung, and In Pil Mo
- Subjects
viruses ,Pneumonia, Viral ,Antibodies, Viral ,Microbiology ,Airborne transmission ,Virus ,Betacoronavirus ,03 medical and health sciences ,0302 clinical medicine ,Virology ,Animals ,Viral shedding ,skin and connective tissue diseases ,Pandemics ,030304 developmental biology ,0303 health sciences ,biology ,SARS-CoV-2 ,Transmission (medicine) ,Viral Vaccine ,Ferrets ,COVID-19 ,virus diseases ,Outbreak ,Viral Vaccines ,respiratory system ,biology.organism_classification ,Virus Shedding ,respiratory tract diseases ,Disease Models, Animal ,Viral replication ,Parasitology ,Coronavirus Infections ,030217 neurology & neurosurgery - Abstract
The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in China and rapidly spread worldwide. To prevent SARS-CoV-2 dissemination, understanding the in vivo characteristics of SARS-CoV-2 is a high priority. We report a ferret model of SARS-CoV-2 infection and transmission that recapitulates aspects of human disease. SARS-CoV-2-infected ferrets exhibit elevated body temperatures and virus replication. Although fatalities were not observed, SARS-CoV-2-infected ferrets shed virus in nasal washes, saliva, urine, and feces up to 8 days post-infection. At 2 days post-contact, SARS-CoV-2 was detected in all naive direct contact ferrets. Furthermore, a few naive indirect contact ferrets were positive for viral RNA, suggesting airborne transmission. Viral antigens were detected in nasal turbinate, trachea, lungs, and intestine with acute bronchiolitis present in infected lungs. Thus, ferrets represent an infection and transmission animal model of COVID-19 that may facilitate development of SARS-CoV-2 therapeutics and vaccines.
- Published
- 2020
- Full Text
- View/download PDF
22. Donor's APOL1 Risk Genotype and 'Second Hits' Associated With De Novo Collapsing Glomerulopathy in Deceased Donor Kidney Transplant Recipients: A Report of 5 Cases
- Author
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Kirk W. Foster, Ali G. Gharavi, Michael B. Stokes, Jae Hyung Chang, Clifford D. Miles, Yifu Li, S. Ali Husain, Sumit Mohan, Krzysztof Kiryluk, Russell J. Crew, Leigh Anne Dale, David J. Cohen, and Dominick Santoriello
- Subjects
Male ,Allograft failure ,Genotype ,030232 urology & nephrology ,Congenital cytomegalovirus infection ,Viremia ,medicine.disease_cause ,Article ,Donor Selection ,03 medical and health sciences ,0302 clinical medicine ,Focal segmental glomerulosclerosis ,Postoperative Complications ,Risk Factors ,BK Virus Infection ,Medicine ,Humans ,030212 general & internal medicine ,Treatment Failure ,business.industry ,urogenital system ,Glomerulosclerosis, Focal Segmental ,Graft Survival ,Middle Aged ,medicine.disease ,Apolipoprotein L1 ,Kidney Transplantation ,BK virus ,Nephrology ,Immunology ,Female ,business ,Kidney disease - Abstract
The presence of two APOL1 risk variants (G1/G1, G1/G2, or G2/G2) is an important predictor of focal segmental glomerulosclerosis (FSGS), and chronic kidney disease in individuals of African descent. While recipient APOL1 genotype is not associated with allograft survival, kidneys from deceased African American donors with two APOL1 risk variants demonstrate shorter graft survival. We present a series of cases of presumed de novo collapsing FSGS in five transplanted kidneys from three deceased donors later identified as carrying two APOL1 risk alleles, including two recipients from the same donor whose kidneys were transplanted in two different institutions across United States. Four of these recipients had viremia in the period preceding the diagnosis of collapsing FSGS. Cytomegalovirus (CMV) and BK virus infection was present in three and one of our five cases, respectively, around the time collapsing FSGS occurred. We discuss viral infections including active CMV infection as possible “second hits” that may lead to glomerular injury and allograft failure in these recipients. Further studies to identify additional “second hits” are necessary to better understand the pathologic mechanisms of donor APOL1-associated kidney disease in the recipient.
- Published
- 2017
23. Expression of interleukin-8, heme oxygenase-1 and vascular endothelial growth factor in DLD-1 colon carcinoma cells exposed to pyrrolidine dithiocarbamate
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Josef Pfeilschifter, Marcel F. Nold, Jae Hyung Chang, Heiko Mühl, Stefan Frank, Markus Hellmuth, and Christian Wetzler
- Subjects
Vascular Endothelial Growth Factor A ,Cancer Research ,Pyrrolidines ,Angiogenesis ,medicine.medical_treatment ,Electrophoretic Mobility Shift Assay ,Enzyme-Linked Immunosorbent Assay ,Endothelial Growth Factors ,Biology ,Monocytes ,chemistry.chemical_compound ,Pyrrolidine dithiocarbamate ,Thiocarbamates ,Tumor Cells, Cultured ,medicine ,Humans ,Interleukin 8 ,Lymphokines ,Tumor Necrosis Factor-alpha ,Vascular Endothelial Growth Factors ,Interleukin-8 ,Interleukin ,General Medicine ,Gene Expression Regulation, Neoplastic ,Heme oxygenase ,Vascular endothelial growth factor ,Cytokine ,chemistry ,Colonic Neoplasms ,Heme Oxygenase (Decyclizing) ,Immunology ,Cancer research ,Tumor necrosis factor alpha - Abstract
Interleukin (IL)-8, heme oxygenase-1 (HO-1), and vascular endothelial growth factor (VEGF) appear to be critically involved in immune responses associated with inflammation, infection and tumor growth. Regulation of these mediators was studied in the human colon carcinoma cell line DLD-1. Here we report that pyrrolidine dithiocarbamate (PDTC) not only augmented tumor necrosis factor-alpha-induced release of IL-8, but also mediated IL-8 expression as a single stimulus. Mutational analysis of the IL-8 promotor and electrophoretic mobility shift analysis revealed that activation of the transcription factor activator protein-1 (AP-1) and a constitutive nuclear factor-kappaB (NF-kappaB) binding activity in DLD-1 cells were mandatory for PDTC-induced IL-8 expression. Besides IL-8, PDTC also upregulated the expression of HO-1 and VEGF in these cells. Induction of IL-8 by PDTC was not restricted to DLD-1 cells, but was observed in Caco-2 colon carcinoma cells and in peripheral blood mononuclear cells. PDTC is currently advocated for use as a chemotherapeutic drug in the treatment of certain malignancies, among them colorectal cancer. Induction of IL-8, HO-1 and VEGF may affect therapeutic applications of this agent.
- Published
- 2002
- Full Text
- View/download PDF
24. Nitric oxide augments release of chemokines from monocytic U937 cells: modulation by anti-inflammatory pathways
- Author
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Heiko Mühl, Rajko Ninic, Jens Paulukat, Jae Hyung Chang, Markus Hellmuth, Markus Bosmann, Marcel F. Nold, Andrea Huwiler, and Josef Pfeilschifter
- Subjects
medicine.medical_specialty ,Chemokine ,Pyridines ,p38 mitogen-activated protein kinases ,medicine.medical_treatment ,Inflammation ,Biology ,Pharmacology ,Nitric Oxide ,p38 Mitogen-Activated Protein Kinases ,Biochemistry ,Dexamethasone ,Monocytes ,Proinflammatory cytokine ,Nitric oxide ,chemistry.chemical_compound ,Transforming Growth Factor beta ,Physiology (medical) ,Internal medicine ,Cyclic AMP ,medicine ,Humans ,Nitric Oxide Donors ,Enzyme Inhibitors ,Chemokine CCL4 ,Rolipram ,Forskolin ,Interleukin-8 ,Imidazoles ,U937 Cells ,Macrophage Inflammatory Proteins ,Protein-Tyrosine Kinases ,Genistein ,Endocrinology ,Cytokine ,chemistry ,biology.protein ,Tetradecanoylphorbol Acetate ,Chemokines ,Mitogen-Activated Protein Kinases ,Triazenes ,medicine.symptom ,Signal Transduction ,medicine.drug - Abstract
Nitric oxide (NO) appears to act as an inflammatory mediator on monocytic cells. Exogenous NO augmented release of chemokines from human promonocytic U937 cells and peripheral blood mononuclear cells. Pharmacological strategies aiming at modulation of NO-induced release of interleukin-8 (IL-8) were investigated in U937 cells in detail. Release of IL-8 was down-regulated by transforming growth factor beta2 (TGF-beta2), by the protein tyrosine-kinase inhibitor genistein, and via rises in intracellular cyclic AMP, generated by prostaglandin E(2), rolipram, pentoxifylline, forskolin, or dibutyryl-cyclic AMP. In addition, incubation with the synthetic glucocorticoid dexamethasone or suppression of activity of p38 mitogen-activated protein (MAP) kinases by SB-203580 modulated release of IL-8. Activation of p38 MAP kinases was confirmed by the demonstration of an augmented appearance of phosphorylated p38 in the presence of NO. The present data suggest that exposure to exogenous NO resembles activation of U937 cells by proinflammatory stimuli. The anti-inflammatory cytokine TGF-beta2, as well as anti-inflammatory or immunosuppressive agents such as genistein, pentoxifylline, rolipram, dexamethasone, and SB-203580 modulate inflammatory, chemokine-inducing actions of NO.
- Published
- 2000
- Full Text
- View/download PDF
25. Direct oral anticoagulant considerations in solid organ transplantation: A review
- Author
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Apostolos Papachristos, Demetra Tsapepas, M. A. Hardy, Spencer T. Martin, Jaclyn T. McKeen, David M. Salerno, and Jae-Hyung Chang
- Subjects
Graft Rejection ,medicine.medical_specialty ,medicine.medical_treatment ,Administration, Oral ,030204 cardiovascular system & hematology ,Article ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,030212 general & internal medicine ,Dosing ,Risks and benefits ,Intensive care medicine ,Transplantation ,business.industry ,Warfarin ,Anticoagulants ,Immunosuppression ,Organ Transplantation ,Clinical trial ,Oral anticoagulant ,Solid organ transplantation ,business ,medicine.drug - Abstract
For more than 60 years, warfarin was the only oral anticoagulation agent available for use in the United States. In many recent clinical trials, several direct oral anticoagulants (DOACs) demonstrated similar efficacy with an equal or superior safety profile, with some other notable benefits. The DOACs have lower inter- and intrapatient variability, much shorter half-lives, and less known drug-drug and drug-food interactions as compared to warfarin. Despite these demonstrated benefits, the use of DOACs has not gained uniform acceptance because of lack of supportive data in special patient populations, including recipients of solid organ transplants maintained on immunosuppression. This review describes the properties of several novel DOACs including their pharmacology and mechanisms of action as they relate to use among solid organ transplant recipients. We have particularly focused on (i) dosing in patients with impaired renal and hepatic function; (ii) considerations for drug-drug interactions with immunosuppressive medications; and (iii) management of the anticoagulated patients at the time of unplanned surgery. The risks and benefits of the use of DOACs in solid organ transplant recipients should be carefully evaluated prior to the introduction of these agents in this highly distinct patient population.
- Published
- 2016
- Full Text
- View/download PDF
26. Assessment of diabetic nephropathy in the Akita mouse
- Author
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Jae-Hyung, Chang and Susan B, Gurley
- Subjects
Disease Models, Animal ,Mice ,Diabetes Mellitus, Type 1 ,Animals ,Insulin ,Point Mutation ,Diabetic Nephropathies ,Genetic Predisposition to Disease ,Angiotensin-Converting Enzyme 2 ,Peptidyl-Dipeptidase A ,Urinalysis ,Kidney - Abstract
Akita mice have type 1 diabetes mellitus caused by a spontaneous point mutation in the Ins2 gene which leads to misfolding of insulin, resulting in pancreatic β-cell failure. Akita mice develop pronounced and sustained hyperglycemia, high levels of albuminuria, and consistent histopathological changes, suggesting that these mice may be suitable as an experimental platform for modeling diabetic nephropathy. One key feature of diabetic kidney disease in Akita mice is that the severity of renal injury is significantly influenced by genetic background. In this chapter, we describe the Akita model and present some of the experimental studies utilizing Akita mice as a model of type 1 diabetes. For example, deficiency in bradykinin receptors, endothelial nitric oxide synthase, or angiotensin-converting enzyme 2 leads to development of functionally and structurally more advanced diabetic nephropathy in these mice, while ketogenic diet has been shown to reverse kidney injury associated with diabetes. This chapter also describes the application of 24-h urine collections from mice for careful measurement of urinary albumin excretion.
- Published
- 2012
27. Diabetic kidney disease in FVB/NJ Akita mice: temporal pattern of kidney injury and urinary nephrin excretion
- Author
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Jean Michel Goujon, Patrick J. Flannery, Jae Hyung Chang, Robert F. Spurney, Susan B. Gurley, Seung Yeol Paik, Lan Mao, William Eisner, Phillip Ruiz, Natalie K Mattocks, Yuping Tang, Samy Hadjadj, and Liming Wang
- Subjects
Male ,Anatomy and Physiology ,endocrine system diseases ,030232 urology & nephrology ,lcsh:Medicine ,Kidney ,urologic and male genital diseases ,Podocyte ,Immunoenzyme Techniques ,Mice ,0302 clinical medicine ,Endocrinology ,Chronic Kidney Disease ,Diabetic Nephropathies ,lcsh:Science ,2. Zero hunger ,0303 health sciences ,Multidisciplinary ,biology ,Podocytes ,Reverse Transcriptase Polymerase Chain Reaction ,Glomerular Hypertrophy ,medicine.anatomical_structure ,Phenotype ,Nephrology ,Medicine ,medicine.symptom ,hormones, hormone substitutes, and hormone antagonists ,Research Article ,medicine.medical_specialty ,endocrine system ,Urinary system ,Blotting, Western ,Mice, Inbred Strains ,Real-Time Polymerase Chain Reaction ,Diabetes Mellitus, Experimental ,Excretion ,Nephrin ,Diabetes Complications ,03 medical and health sciences ,Internal medicine ,Genetic model ,medicine ,Albuminuria ,Animals ,RNA, Messenger ,030304 developmental biology ,Diabetic Endocrinology ,Renal Physiology ,business.industry ,urogenital system ,lcsh:R ,Membrane Proteins ,Renal System ,Diabetes Mellitus Type 1 ,Disease Models, Animal ,Diabetes Mellitus, Type 1 ,Hyperglycemia ,biology.protein ,lcsh:Q ,business ,Biomarkers - Abstract
Akita mice are a genetic model of type 1 diabetes. In the present studies, we investigated the phenotype of Akita mice on the FVB/NJ background and examined urinary nephrin excretion as a marker of kidney injury. Male Akita mice were compared with non-diabetic controls for functional and structural characteristics of renal and cardiac disease. Podocyte number and apoptosis as well as urinary nephrin excretion were determined in both groups. Male FVB/NJ Akita mice developed sustained hyperglycemia and albuminuria by 4 and 8 weeks of age, respectively. These abnormalities were accompanied by a significant increase in systolic blood pressure in 10-week old Akita mice, which was associated with functional, structural and molecular characteristics of cardiac hypertrophy. By 20 weeks of age, Akita mice developed a 10-fold increase in albuminuria, renal and glomerular hypertrophy and a decrease in the number of podocytes. Mild-to-moderate glomerular mesangial expansion was observed in Akita mice at 30 weeks of age. In 4-week old Akita mice, the onset of hyperglycemia was accompanied by increased podocyte apoptosis and enhanced excretion of nephrin in urine before the development of albuminuria. Urinary nephrin excretion was also significantly increased in albuminuric Akita mice at 16 and 20 weeks of age and correlated with the albumin excretion rate. These data suggest that: 1. FVB/NJ Akita mice have phenotypic characteristics that may be useful for studying the mechanisms of kidney and cardiac injury in diabetes, and 2. Enhanced urinary nephrin excretion is associated with kidney injury in FVB/NJ Akita mice and is detectable early in the disease process.
- Published
- 2012
28. Assessment of Diabetic Nephropathy in the Akita Mouse
- Author
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Susan B. Gurley and Jae Hyung Chang
- Subjects
endocrine system ,Type 1 diabetes ,medicine.medical_specialty ,endocrine system diseases ,business.industry ,medicine.medical_treatment ,Insulin ,Renal function ,medicine.disease ,Diabetic nephropathy ,Endocrinology ,Internal medicine ,Diabetes mellitus ,Angiotensin-converting enzyme 2 ,medicine ,Albuminuria ,medicine.symptom ,business ,hormones, hormone substitutes, and hormone antagonists ,Ketogenic diet - Abstract
Akita mice have type 1 diabetes mellitus caused by a spontaneous point mutation in the Ins2 gene which leads to misfolding of insulin, resulting in pancreatic β-cell failure. Akita mice develop pronounced and sustained hyperglycemia, high levels of albuminuria, and consistent histopathological changes, suggesting that these mice may be suitable as an experimental platform for modeling diabetic nephropathy. One key feature of diabetic kidney disease in Akita mice is that the severity of renal injury is significantly influenced by genetic background. In this chapter, we describe the Akita model and present some of the experimental studies utilizing Akita mice as a model of type 1 diabetes. For example, deficiency in bradykinin receptors, endothelial nitric oxide synthase, or angiotensin-converting enzyme 2 leads to development of functionally and structurally more advanced diabetic nephropathy in these mice, while ketogenic diet has been shown to reverse kidney injury associated with diabetes. This chapter also describes the application of 24-h urine collections from mice for careful measurement of urinary albumin excretion.
- Published
- 2012
- Full Text
- View/download PDF
29. Calcineurin (CN) Activation Promotes Apoptosis of Glomerular Podocytes Both in Vitro and in Vivo
- Author
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Yuping Tang, Seung-Yeol Paik, Jae-Hyung Chang, Robert F. Spurney, William Eisner, and Liming Wang
- Subjects
Blood Glucose ,medicine.medical_specialty ,medicine.medical_treatment ,Kidney Glomerulus ,Apoptosis ,Biology ,Models, Biological ,Dinoprostone ,Tacrolimus ,Transactivation ,Mice ,Endocrinology ,Internal medicine ,Genetic model ,medicine ,Albuminuria ,Animals ,Molecular Biology ,Original Research ,NFATC Transcription Factors ,Podocytes ,Calcineurin ,NFAT ,General Medicine ,Angiotensin II ,Cell biology ,Cyclooxygenase 2 ,GTP-Binding Protein alpha Subunits, Gq-G11 ,Signal transduction ,Reactive Oxygen Species ,Oligopeptides ,Prostaglandin E ,Densitometry ,Signal Transduction - Abstract
To determine the role of Gq signaling and calcineurin (CN) activation in promoting apoptosis of glomerular podocytes, constitutively active Gq [Gq(+)] or CN [CN(+)] proteins were introduced into cultured podocytes using protein transduction by tagging the proteins with the transactivator of transcription peptide. To investigate the role of CN in promoting podocyte apoptosis in vivo, a genetic model of type 1 diabetes mellitus (Akita mice) was treated with the CN inhibitor FK506. In cultured podocytes, Gq(+) stimulated nuclear translocation of nuclear factor of activated T cells (NFAT) family members, activated an NFAT reporter construct, and enhanced podocyte apoptosis in a CN-dependent fashion. CN(+) similarly promoted podocyte apoptosis, and apoptosis induced by either angiotensin II or endothelin-1 was blocked by FK506. Induction of apoptosis required NFAT-induced gene transcription because apoptosis induced by either Gq(+) or CN(+) was blocked by an inhibitor that prevented CN-dependent NFAT activation without affecting CN phosphatase activity. Podocyte apoptosis was mediated, in part, by the NFAT-responsive gene cyclooxygenase 2 (COX2) and prostaglandin E(2) generation because apoptosis induced by Gq(+) was attenuated by either COX2 inhibition or blockade of the Gq-coupled E-series prostaglandins receptor. The findings appeared relevant to podocyte apoptosis in diabetic nephropathy because apoptosis was significantly reduced in Akita mice by treatment with FK506. These data suggest that Gq stimulates CN and promotes podocyte apoptosis both in vitro and in vivo. Apoptosis requires NFAT-dependent gene transcription and is mediated, in part, by CN-dependent COX2 induction, prostaglandin E(2) generation, and autocrine activation of the Gq-coupled E-series prostaglandins receptor.
- Published
- 2011
30. Left-handed surgeons: are they left out?
- Author
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Prasad S. Adusumilli, Jae-Hyung Chang, I. Michael Leitman, Scott Tuorto, and Christian A. Kell
- Subjects
Male ,medicine.medical_specialty ,Attitude of Health Personnel ,education ,MEDLINE ,Functional Laterality ,Physicians ,Medicine ,Humans ,Laparoscopy ,Left handed ,medicine.diagnostic_test ,Career Choice ,Education, Medical ,business.industry ,General surgery ,Data Collection ,Mentors ,Medical school ,Outcome measures ,Latin word ,Middle Aged ,Surgical Instruments ,Surgical training ,Surgery ,General Surgery ,Female ,Perception ,business ,Career choice - Abstract
Background Left-handedness has been considered a simple inconvenience by some or something as convoluted as "the sinister," the Latin word for the left, by others. One in ten medical personnel is left-handed. The perceptions of left-handed surgeons regarding their laterality related inconveniences are unknown. Objectives To determine the perceptions of left-handed surgeons and the way it has affected their surgical training and career. Design and setting Web-based survey of left-handed surgeons. Participants Left-handed surgeons in 2 boroughs of New York City, Manhattan and Brooklyn. Methods Distribution and completion of the survey. Main outcome measure Career-oriented concerns of left-handed surgeons. Results Three percent of left-handed surgeons received laterality related mentoring during medical school. Ten percent of the programs mentored left-handed surgical residents, and 13% of the programs provided left-handed instruments during surgical residency. Laparoscopy and laparoscopic instruments did not eliminate the problems associated with instrument handling to left-handed surgeons. Ten percent of the left-handed surgeons expressed concerns when asked whether they would be comfortable being treated by another left-handed surgeon when they are the patients themselves. Conclusions This study reveals the perceptions of left-handed surgeons in adapting to a right-handed world. Early laterality related mentoring in medical school and during surgical residency with provision of left-handed instruments might reduce the inconveniences of left-handed surgeons learning.
- Published
- 2004
31. Expression and release of chemokines associated with apoptotic cell death in human promonocytic U937 cells and peripheral blood mononuclear cells
- Author
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Stefan Frank, Wolfgang Eberhardt, Heiko Mühl, Marcel F. Nold, Jae Hyung Chang, and Josef Pfeilschifter
- Subjects
Chemokine ,Programmed cell death ,Serine Proteinase Inhibitors ,Pyridines ,p38 mitogen-activated protein kinases ,Immunology ,Inflammation ,Apoptosis ,Biology ,Peripheral blood mononuclear cell ,medicine ,Immunology and Allergy ,Macrophage ,Humans ,Enzyme Inhibitors ,Etoposide ,U937 cell ,Tumor Necrosis Factor-alpha ,Tosylphenylalanyl Chloromethyl Ketone ,Interleukin-8 ,Imidazoles ,U937 Cells ,Molecular biology ,Cell biology ,biology.protein ,Leukocytes, Mononuclear ,Cladribine ,medicine.symptom ,Chemokines ,Triazenes - Abstract
To characterize mechanisms which may determine the fate of apoptotic cells, we investigated chemokine expression in apoptotic promonocytic U937 cells or peripheral blood mononuclear cells (PBMC). Exposure of U937 cells to etoposide (VP-16) or the nitric oxide (NO) donor DETA-NO, both inducers of apoptosis in these cells, was associated with increased expression of the chemokines IL-8 and macrophage inflammatory protein-1 alpha. Up-regulation of IL-8 mRNA expression by VP-16 or DETA-NO was observed as early as 4 h or 6 h, respectively, after onset of treatment and was still detectable after 19 h of exposure. A serine protease inhibitor prevented both VP-16-induced apoptosis and release of IL-8, whereas inhibition of p38 MAP kinases reduced IL-8 secretion only. Moreover, we observed that incubation with 2-chlorodeoxyadenosine (CdA) up-regulated release of IL-8 from adherent PBMC in parallel to induction of apoptosis. In these cells a modest but significant induction of TNF-alpha release by CdA was also detected. In addition, CdA augmented release of IL-8 from whole blood cultures. By facilitating adequate recruitment of phagocytes to sites of cell death, stress-induced up-regulation of chemokines associated with apoptosis may contribute to mechanisms aiming at efficient removal of apoptotic cells.
- Published
- 1999
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