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Rao PS, Reed K, Modi N, Handler D, de Guex KP, Yu S, Kagan L, Reiss R, Narayanan N, Peloquin CA, Lardizabal A, Vinnard C, Thomas TA, Xie YL, Heysell SK. Isoniazid urine spectrophotometry for prediction of serum pharmacokinetics in adults with TB. IJTLD Open 2024; 1:90-95. [PMID: 38655375 PMCID: PMC11037464 DOI: 10.5588/ijtldopen.23.0361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
BACKGROUND Isoniazid (INH) is an important drug in many TB regimens, and unfavorable treatment outcomes can be caused by suboptimal pharmacokinetics. Dose adjustment can be personalized by measuring peak serum concentrations; however, the process involves cold-chain preservation and laboratory techniques such as liquid chromatography (LC)/mass spectrometry (MS), which are unavailable in many high-burden settings. Urine spectrophotometry could provide a low-cost alternative with simple sampling and quantification methods. METHODS We enrolled 56 adult patients on treatment for active TB. Serum was collected at 0, 1, 2, 4, 6, and 8 h for measurement of INH concentrations using validated LC-MS/MS methods. Urine was collected at 0-4, 4-8, and 8-24 h intervals, with INH concentrations measured using colorimetric methods. RESULTS The median peak serum concentration and total serum exposure over 24 h were 4.8 mg/L and 16.4 mg*hour/L, respectively. Area under the receiver operator characteristic curves for urine values predicting a subtherapeutic serum concentration (peak <3.0 mg/L) were as follows: 0-4 h interval (AUC 0.85, 95% CI 0.7-0.96), 0-8 h interval (AUC 0.85, 95% CI 0.71-0.96), and 0-24 h urine collection interval (AUC 0.84, 95% CI 0.68-0.96). CONCLUSION Urine spectrophotometry may improve feasibility of personalized dosing in high TB burden regions but requires further study of target attainment following dose adjustment based on a urine threshold.
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Affiliation(s)
- P S Rao
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, VA
| | - K Reed
- School of Arts and Sciences, University of Virginia, Charlottesville, VA
| | - N Modi
- Public Health Research Institute and Global Tuberculosis Institute, Rutgers New Jersey Medical School, Newark, NJ
| | - D Handler
- Public Health Research Institute and Global Tuberculosis Institute, Rutgers New Jersey Medical School, Newark, NJ
| | - K Petros de Guex
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, VA
| | - S Yu
- Department of Pharmaceutics and Center of Excellence for Pharmaceutical Translational Research and Education, Ernest Mario School of Pharmacy, Rutgers State University of New Jersey, Newark, NJ
| | - L Kagan
- Department of Pharmaceutics and Center of Excellence for Pharmaceutical Translational Research and Education, Ernest Mario School of Pharmacy, Rutgers State University of New Jersey, Newark, NJ
| | - R Reiss
- Public Health Research Institute and Global Tuberculosis Institute, Rutgers New Jersey Medical School, Newark, NJ
| | - N Narayanan
- Department of Pharmaceutics and Center of Excellence for Pharmaceutical Translational Research and Education, Ernest Mario School of Pharmacy, Rutgers State University of New Jersey, Newark, NJ
| | - C A Peloquin
- College of Pharmacy and Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA
| | - A Lardizabal
- Public Health Research Institute and Global Tuberculosis Institute, Rutgers New Jersey Medical School, Newark, NJ
| | - C Vinnard
- Public Health Research Institute and Global Tuberculosis Institute, Rutgers New Jersey Medical School, Newark, NJ
| | - T A Thomas
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, VA
| | - Y L Xie
- Public Health Research Institute and Global Tuberculosis Institute, Rutgers New Jersey Medical School, Newark, NJ
| | - S K Heysell
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, VA
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Pondugula SR, Salamat JM, Abbott KL, Flannery PC, Majrashi M, Almaghrabi M, Govindarajulu M, Ramesh S, Sandey M, Onteru SK, Huang CCJ, Iwaki Y, Gill K, Narayanan N, McElroy E, Desai D, Nadar R, Moore T, Dhanasekaran M. A clinically relevant combination treatment with doxorubicin and cyclophosphamide does not induce hepatotoxicity in C57BL/6J mice. Liver Res 2021; 5:239-242. [PMID: 34900377 PMCID: PMC8663913 DOI: 10.1016/j.livres.2021.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND AND AIM Chronic exposure to chemotherapeutics can lead to severe adverse events including hepatotoxicity. A combination chemotherapy regimen of doxorubicin (DOX) and cyclophosphamide (CPS) is employed in treatment of several cancers such as leukemia, lymphoma, and breast cancer. It is not well understood whether a combination therapy of DOX and CPS can induce hepatotoxicity. We therefore sought to determine whether co-administration of DOX and CPS at their clinically relevant doses and frequency results in hepatotoxicity. METHODS Male C57BL/6J mice received one intraperitoneal injection of saline or DOX-2mg /kg and CPS-50mg/kg once a week for 4 weeks. After the treatment period, liver histology and various serum biomarkers of hepatotoxicity were assessed. RESULTS Co-treatment of DOX and CPS did not alter the serum levels of alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin, albumin, globulin, or total protein. Similarly, co-administration of DOX and CPS did not result in a noticeable change in liver histology. However, it was notable that the concomitant treatment with DOX and CPS resulted in a significant increase in serum levels of aspartate aminotransferase (AST). Elevated serum AST levels were also associated with increased serum creatinine kinase (CK) levels, suggesting that the elevated serum AST levels are likely due to muscle injury following the co-administration of DOX and CPS. CONCLUSION Taken together, our results, for the first time, suggest that co-administration of DOX and CPS, at their clinically relevant doses and frequency does not induce a significant hepatotoxicity in the mice.
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Affiliation(s)
- Satyanarayana R Pondugula
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA,Corresponding Authors: Satyanarayana R. Pondugula, DVM, PhD, Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, Phone: 334-844-8505, Fax: 334-844-4542, , Muralikrishnan Dhanasekaran, M.Pharm., PG. DPM & IR, Ph.D, Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, , Phone: 334-844-8327
| | - Julia M Salamat
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Kodye L Abbott
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Patrick C Flannery
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Mohammed Majrashi
- Department of Pharmacology, Faculty of Medicine, University of Jeddah, Jeddah, Saudi Arabia,Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Mohammed Almaghrabi
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Manoj Govindarajulu
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Sindhu Ramesh
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Maninder Sandey
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, AL 36849, USA
| | - Suneel K Onteru
- Animal Biochemistry Division, National Dairy Research Institute, ICAR-NDRI, Karnal, Haryana 132001, India
| | - Chen-Che J Huang
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Yoshimi Iwaki
- Department of Clinical Science, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Kristina Gill
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Natasha Narayanan
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Edwin McElroy
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Darshini Desai
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Rishi Nadar
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Timothy Moore
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Muralikrishnan Dhanasekaran
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA,Corresponding Authors: Satyanarayana R. Pondugula, DVM, PhD, Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, Phone: 334-844-8505, Fax: 334-844-4542, , Muralikrishnan Dhanasekaran, M.Pharm., PG. DPM & IR, Ph.D, Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, , Phone: 334-844-8327
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3
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Pondugula SR, Majrashi M, Almaghrabi M, Ramesh S, Abbott KL, Govindarajulu M, Gill K, Fahoury E, Narayanan N, Desai D, Ren J, Nadar R, McElroy T, Moore T, Majeed M, Kalyanam N, Dhanasekaran M. Oroxylum Indicum ameliorates chemotherapy induced cognitive impairment. PLoS One 2021; 16:e0252522. [PMID: 34081735 PMCID: PMC8174701 DOI: 10.1371/journal.pone.0252522] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 05/13/2021] [Indexed: 12/02/2022] Open
Abstract
While chemotherapy is the most effective therapeutic approach for treating a variety of cancer patients, commonly used chemotherapeutic agents, often induce several adverse effects. Escalating evidence indicates that chemotherapeutics, particularly doxorubicin (DOX) and cyclophosphamide (CPS), induce cognitive impairment associated with central nervous system toxicity. This study was performed to determine neuroprotective effects of Oroxylum indicum extract (OIE) in regard to preventing chemotherapy induced cognitive impairment (CICI) occurring after 4 cycles of DOX (2mg/kg) and CPS (50mg/kg) combination chemotherapy in male C57BL/6J mice. OIE significantly prevented the chemotherapy impaired short-term cognitive performance, exploratory behavior associated with cognitive performance, cognitive performance, and spatial learning and memory in the Y-maze, Open-Field, Novel Object Recognition, and Morris Water Maze tests, respectively. These data suggest that OIE protects from the CICI. OIE decreased the reactive oxygen species and lipid peroxide generated by the chemotherapy treatment in the brain, while also blocking the chemotherapy-induced glutathione depletion. These results establish that OIE exhibits potent antioxidant activity in chemotherapy treated mice. Notably, OIE significantly increased the Complex-I and Complex-IV activities in the brain, indicating that OIE enhances mitochondrial function in the brain. In silico analysis of the major active chemical constituents (Oroxylin A, Baicalein and Chrysin) of OIE indicated that OIE has a favorable absorption, distribution, metabolism and excretion (ADME) profile. Taken together, our results are consistent with the conclusion that OIE prevents CICI by counteracting oxidative stress and perhaps by improving mitochondrial function.
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Affiliation(s)
- Satyanarayana R. Pondugula
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, United States of America
- * E-mail: (MD); (SRP)
| | - Mohammed Majrashi
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
- Department of Pharmacology, Faculty of Medicine, University of Jeddah, Jeddah, Saudi Arabia
| | - Mohammed Almaghrabi
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
| | - Sindhu Ramesh
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
| | - Kodye L. Abbott
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, United States of America
| | - Manoj Govindarajulu
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
| | - Kristina Gill
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, United States of America
| | - Eddie Fahoury
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
| | - Natasha Narayanan
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, United States of America
| | - Darshini Desai
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
| | - Jun Ren
- School of Pharmacy, University of Wyoming College of Health Sciences, Laramie, Wyoming, United States of America
| | - Rishi Nadar
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
| | - Trey McElroy
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, United States of America
| | - Timothy Moore
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
| | - Muhammed Majeed
- Sabinsa Corporation, East Windsor, New Jersey, United States of America
| | | | - Muralikrishnan Dhanasekaran
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, United States of America
- * E-mail: (MD); (SRP)
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4
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Pondugula SR, Salamat JM, Abbott KL, Flannery PC, Majrashi M, Almaghrabi M, Govindarajulu M, Ramesh S, Onteru SK, Sandey M, Huang CC, Gill K, Narayanan N, McElroy E, Desai D, Nadar R, Moore T, Nagabhushanam K, Majeed M, Dhanasekaran M. Oroxylum indicum extract, at a physiologically relevant dosage, does not induce hepatotoxicity in C57BL/6J mice. Nat Prod Commun 2021; 16. [PMID: 34306298 DOI: 10.1177/1934578x211016966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background Botanical supplements have been proven to provide beneficial health effects. However, they can induce unintended adverse events such as hepatotoxicity. Oroxylum indicum extract (OIE, Sabroxy®) has several health benefits including anti-inflammatory, anti-arthritic, antifungal, antibacterial, and neuroprotective effects. It is currently unknown whether OIE has the potential to induce hepatotoxicity. Purpose In the current study, we sought to determine whether OIE can induce hepatotoxicity in C57BL/6J mouse model. Methods The male mice were fed powdered rodent food (control group) or powdered rodent food mixed with OIE (Sabroxy®, 500mg/kg) daily for 4 weeks. Following the treatment, we assessed liver histology and serum levels of biomarkers commonly associated with liver damage, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP). Results No significant alterations were observed in liver histology, and serum levels of ALT, AST, ALP, bilirubin, albumin, globulin and total protein in the OIE fed mice compared to the control mice. Conclusion Taken together, our results suggest that OIE, when fed at its physiologically relevant dosage, does not induce hepatotoxicity in C57BL/6J mice.
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Affiliation(s)
- Satyanarayana R Pondugula
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Julia M Salamat
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Kodye L Abbott
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Patrick C Flannery
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Mohammed Majrashi
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Mohammed Almaghrabi
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Manoj Govindarajulu
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Sindhu Ramesh
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Suneel K Onteru
- Animal Biochemistry Division, National Dairy Research Institute, ICAR-NDRI, Karnal, Haryana 132001, India
| | - Maninder Sandey
- Department of Pathobiology, College of Veterinary Medicine, Auburn Univeristy, AL 36849, USA
| | - Chen-Che Huang
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Kristina Gill
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Natasha Narayanan
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Edwin McElroy
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
| | - Darshini Desai
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Rishi Nadar
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | - Timothy Moore
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
| | | | | | - Muralikrishnan Dhanasekaran
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
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Murugan R, Hastie C, Narayanan N, Wong S. 622 Potential Application of Electrocardiographs (ECG) to Diagnose Breech Presentations of Fetuses. Br J Surg 2021. [DOI: 10.1093/bjs/znab134.210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Breech presentation, i.e. the abnormal lie of a foetus longitudinally with the buttocks closest to the mother’s cervix, is a common issue affecting up to 5% of women during delivery resulting in poor outcomes such as traumatic labour, infection and increased neonatal mortality.
Currently, abdominal palpation is the screening method of choice for breech presentation; however, 15,000 breech presentations remain undiagnosed across England annually. While routine ultrasonography has been suggested, its cost-effectiveness and scalability remain concerning, especially in low/middle-income countries.
Various algorithms have been applied to maternal trans-abdominal ECGs to obtain foetal ECGs, but current applications only allow heart rates, congenital heart defects, hypoxia, and foetal distress to be identified. The use of ECG is proposed to determine foetal position as breech foetuses tend to display QRS complexes in a similar pattern to the maternal trace, whereas cephalic foetuses would demonstrate inverted QRS complexes.
ECGs are cost-effective, safe and do not require highly skilled technicians to operate, which makes it an ideal starting platform for the development of a device with high sensitivity and reasonable diagnostic speeds to identify breech foetuses. Future considerations include the use of artificial intelligence to increase diagnostic accuracy and development of a patient-facing mobile application.
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Affiliation(s)
- R Murugan
- University of Edinburgh, Edinburgh, United Kingdom
| | - C Hastie
- University of Edinburgh, Edinburgh, United Kingdom
| | - N Narayanan
- University of Edinburgh, Edinburgh, United Kingdom
| | - S Wong
- University of Edinburgh, Edinburgh, United Kingdom
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6
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Salamat J, Abbott K, Flannery P, Majrashi M, Almaghrabi M, Govindarajulu M, Ramesh S, Sandey M, Onteru S, Huang C, Iwaki Y, Gill K, Narayanan N, McElroy E, Desai D, Nadar R, Ward K, Ledbetter E, Moore T, Dhanasekaran M, Pondugula S. A clinically relevant combination treatment of doxorubicin and cyclophosphamide does not induce hepatotoxicity in C57BL/6J mice. FASEB J 2021. [DOI: 10.1096/fasebj.2021.35.s1.02914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Julia Salamat
- Department of Anatomy, Physiology and PharmacologyAuburn UniversityAuburnAL
| | - Kodye Abbott
- Department of Anatomy, Physiology and PharmacologyAuburn UniversityAuburnAL
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7
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Salamat J, Abbott K, Flannery P, Majrashi M, Almaghrabi M, Govindarajulu M, Ramesh S, Onteru S, Sandey M, Huang C, Gill K, Narayanan N, McElroy E, Desai D, Nadar R, Moore T, Nagabhushanam K, Majeed M, Dhanasekaran M, Pondugula S. Oroxylum indicum
extract, at a physiologically relevant dosage, does not induce hepatotoxicity in C57BL/6J mice. FASEB J 2021. [DOI: 10.1096/fasebj.2021.35.s1.03169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Nair AG, Narayanan N, Ali MJ. A Survey on the Impact of COVID-19 on Lacrimal Surgery: The Asia-Pacific Perspective. Clin Ophthalmol 2020; 14:3789-3799. [PMID: 33177805 PMCID: PMC7649246 DOI: 10.2147/opth.s279728] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 09/30/2020] [Indexed: 12/13/2022] Open
Abstract
Aim To assess the impact of the COVID-19 pandemic-related lockdown on lacrimal surgery among oculoplastic surgeons in the Asia-Pacific region. Methods An institutional board review approved anonymous electronic survey was sent out via email to oculoplastic surgeons across the Asia-Pacific region. All responses were tabulated and analysed. Results A total of 259 valid responses were received. Nearly 87% of the surgeons agreed that lacrimal procedures were associated with a high risk of COVID-19 transmission. In all, at the time of taking the survey, 151/259 (58.3%) of the surgeons were not performing any lacrimal surgeries in view of the COVID-19 pandemic and 71/259 (27.4%) of the respondents were only performing emergency lacrimal surgeries. External dacryocystorhinostomy was the most commonly performed lacrimal procedure across the region and lacrimal procedures contributed to at least 25% of the income for nearly a third of the respondents. Majority of the respondents were female (52.9%), but a significantly higher proportion of male oculoplastic surgeons were still performing lacrimal surgeries during the lockdown. Over 75% of respondents indicated that resuming lacrimal procedures is important to their practice. Conclusion The survey showed that there was a general agreement among the surveyed oculoplastic surgeons in the Asia-Pacific region that lacrimal procedures were associated with a high risk of COVID-19 transmission and over 85% of them of had either stopped performing elective lacrimal surgeries altogether or were providing only emergent care. It is likely that not performing elective lacrimal procedures, COVID-19 has financially impacted a high percentage of the surveyed oculoplastic surgeons.
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Affiliation(s)
- Akshay Gopinathan Nair
- Ophthalmic Plastic Surgery and Ocular Oncology Services, Aditya Jyot Eye Hospital, Mumbai 400 031, India.,Advanced Eye Hospital & Institute, Navi Mumbai 400 705, India
| | | | - Mohammad Javed Ali
- Govindram Seksaria Institute of Dacryology, L.V. Prasad Eye Institute, Hyderabad, Telangana 600 034, India
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Pondugula SR, Majrashi M, Almaghrabi M, Abbott K, Govindarajulu M, Ramesh S, Gill K, Fahoury E, Narayanan N, Desai D, Nadar R, McElroy E, Moore T, Dhanasekaran M. Predictable hematological markers associated with cognitive decline in valid rodent models of cognitive impairment. Toxicol Mech Methods 2020; 30:454-461. [PMID: 32329394 DOI: 10.1080/15376516.2020.1760984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Endogenous (hyperglycemia) and exogenous (therapeutic, prophylactic, street drugs) factors can considerably contribute to cognitive impairment (CI). Currently, there are few invasive and/or noninvasive markers that correlate with CI and those that do exist require expensive or invasive techniques to predict and accurately measure the cognitive decline. Therefore, we sought to determine hematological markers as predictors of CI in two different chemically induced valid rodent models of CI (streptozotocin induced hyperglycemic model and chemotherapy [doxorubicin/cyclophosphamide] treated rodent model). Hematological markers were analyzed in the above rodent models of CI CI and compared to their respective control groups. There was a significant increase in creatinine kinase, lactate dehydrogenase and aspartate aminotransferase (AST) in the chemotherapy group. Blood urea nitrogen (BUN), alkaline phosphatase (ALP), bilirubin, creatinine and glucose levels were significantly increased in the streptozotocin group. Interestingly, triglycerides were significantly elevated in both the streptozotocin and chemotherapy groups. Previous studies with human subjects have shown a potential link between the increase in triglyceride levels and CI. Likewise, our data indicate a notable correlation with an increase in triglycerides to cognitive impairment in the rodent models. This suggests elevated levels of triglycerides could prove to be a potential noninvasive hematological marker for the increased risk of CI. Further studies are warranted to determine the causal relationship between elevated triglyceride levels and CI.
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Affiliation(s)
- Satyanarayana R Pondugula
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Mohammed Majrashi
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Mohammed Almaghrabi
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Kodye Abbott
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Manoj Govindarajulu
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Sindhu Ramesh
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Kristina Gill
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA.,Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Eddie Fahoury
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Natasha Narayanan
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Darshini Desai
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Rishi Nadar
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Edwin McElroy
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Timothy Moore
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Muralikrishnan Dhanasekaran
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
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10
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Pondugula SR, Majrashi M, Almaghrabi M, Abbott KL, Govindarajulu M, Ramesh S, Gill K, Fahoury E, Narayanan N, Desai D, Nadar R, McElroy E, Moore T, Nagabhushanam K, Majeed M, Dhanasekaran M. Oroxylum indicum
extract prevents chemotherapy‐induced cognitive impairment in mice. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.07348] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Salamat JM, Abbott KL, Majrashi M, Almaghrabi M, Govindarajulu M, Ramesh S, Gill K, Fahoury E, Narayanan N, Desai D, Nadar R, McElroy E, Moore T, Nagabhushanam K, Majeed M, Pondugula S, Dhanasekaran M. Oroxylum indicum
extract does not induce hepatotoxicity in mice. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.07406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abbott KL, Salamat JM, Flannery PC, Chaudhury CS, Narayanan N, Chandran A, Vishveshwara S, Mani S, Pondugula SR. Gefitinib, at Its Clinically Relevant Concentrations, Inhibits Rifampicin‐Induced CYP3A4 Gene Expression in Human Hepatocytes. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.07255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Nair A, Narayanan N, Padwal U, Gopinathan I, Pathak R. Malignant melanoma of the rectum presenting as orbital metastasis. Indian J Ophthalmol 2020; 68:2620-2622. [PMID: 33120715 PMCID: PMC7774230 DOI: 10.4103/ijo.ijo_847_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
An orbital mass being the presenting sign of disseminated systemic metastasis is a rare clinical picture. Here, the authors describe the case of a 52-year old Asian-Indian female who presented with unilateral proptosis and motility restriction. Imaging showed an irregular orbital mass infiltrating the right lateral rectus and with a significant intraconal component. Incisional biopsy helped to diagnose a malignant melanoma and exhaustive systemic imaging showed that the primary was found to be arising from the rectum. This represents the first reported case of malignant melanoma of the rectum metastasizing to the orbit and presenting with proptosis and reduced vision.
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Abbott KL, Chaudhury CS, Narayanan N, Pondugula SR. Belinostat Inhibits Rifampicin Induced CYP3A4 and MDR1 Gene Expression. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.694.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kodye L. Abbott
- Anatomy, Physiology and PharmacologyAuburn UniversityAuburnAL
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Gill K, Ramesh S, Majrashi M, Almaghrabi M, Desai D, Abbott K, Fahoury E, McElroy T, Narayanan N, Nadar R, Moore T, Pondugula S, Dhanasekaran M. Triglycerides: A Potential Hematological Marker in Animal Models of Cognitive Impairment. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.lb615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kristina Gill
- Drug Discovery & DevelopmentAuburn University Harrison School of PharmacyAuburnAL
| | - Sindhu Ramesh
- Drug Discovery & DevelopmentAuburn University Harrison School of PharmacyAuburnAL
| | - Mohammed Majrashi
- Drug Discovery & DevelopmentAuburn University Harrison School of PharmacyAuburnAL
| | - Mohammed Almaghrabi
- Drug Discovery & DevelopmentAuburn University Harrison School of PharmacyAuburnAL
| | - Darshini Desai
- Drug Discovery & DevelopmentAuburn University Harrison School of PharmacyAuburnAL
| | - Kodye Abbott
- Auburn University College of Veterinary MedicineAuburnAL
| | - Eddie Fahoury
- Drug Discovery & DevelopmentAuburn University Harrison School of PharmacyAuburnAL
| | - Trey McElroy
- Auburn University College of Veterinary MedicineAuburnAL
| | | | - Rishi Nadar
- Drug Discovery & DevelopmentAuburn University Harrison School of PharmacyAuburnAL
| | - Timothy Moore
- Drug Discovery & DevelopmentAuburn University Harrison School of PharmacyAuburnAL
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Vedha Hari B, Lu CL, Narayanan N, Wang RR, Zheng YT. Engineered polymeric nanoparticles of Efavirenz: Dissolution enhancement through particle size reduction. Chem Eng Sci 2016. [DOI: 10.1016/j.ces.2016.08.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Randall G, Connell S, Narayanan N, Messingham K, Fairley J. 056 Collagen XVII autoantibodies in Parkinsons disease sera react with tyrosine hydroxylase positive neurons, but not epidermal basement membrane zone. J Invest Dermatol 2016. [DOI: 10.1016/j.jid.2016.02.081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Narayanan N, Gowri R, Maheswaran A, Harshapriya G, Deattu N, Ravi Nargis NR. Health Assessment and Case Analysis of Diabetes in Rural Population of Thiruvallur District, Tamilnadu, India. Journal of Pharmaceutical Research 2015. [DOI: 10.18579/jpcrkc/2015/14/3/85273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Vedha Hari BN, Narayanan N, Dhevedaran K. Efavirenz–eudragit E-100 nanoparticle-loaded aerosol foam for sustained release: in-vitro and ex-vivo evaluation. Chemical Papers 2015. [DOI: 10.1515/chempap-2015-0005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe control of HIV infection using antiretroviral agents, especially through targeted delivery, has attracted extensive attention in the last decade. Recently, the vaginal route of administration has become the one most recommended for HIV infections during pregnancy. Efavirenz is a non-nucleoside reverse transcriptase inhibitor anti-HIV drug and its prolonged half-life helps achieve long-term preexposure prophylaxis of HIV-1 infections; it is used as a first-line drug in the treatment using combination therapy. Nanotechnology has received attention as a major area of research into drug delivery in recent years. The aerosol foam formulation is packed under pressure and contains therapeutically active ingredients that are released as foam on the activation of an appropriate valve system. The objective of this study was to develop an aerosol foam formulation of efavirenz nanoparticles for vaginal drug delivery. The nanoparticles were prepared using the emulsion solvent evaporation method and converted into an aerosol foam formulation with the addition of 0.1 mass % of sodium lauryl sulphate as a foaming agent and pressurised with 1,1,1,2-tetrafluroethane. The nanoparticles containing the formulation and aerosol foam formulation were individually characterised by applying various tests such as particle size, zeta potential, pH, viscosity, drug content, entrapment efficiency, drug release studies and release kinetics. The compatibility of the materials was evaluated using FT-IR, polymorphic changes by TGA-DSC and also the morphological properties using SEM study. Foam density, bubble size and collapse time were evaluated in the aerosol-foam formulation; in addition, the drug content and release studies were compared with nanoparticle formulation. The results revealed that the nanoparticle-containing formulation and aerosol formulations were stable and the foam emerged as grade one with fine bubbles and became coarser over time.
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Givvimani S, Narayanan N, Armaghan F, Pushpakumar S, Tyagi SC. Attenuation of conducted vasodilation in skeletal muscle arterioles during hyperhomocysteinemia. Pharmacology 2013; 91:287-96. [PMID: 23736684 DOI: 10.1159/000350394] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 03/03/2013] [Indexed: 11/19/2022]
Abstract
BACKGROUND Vasomotor responses conducted from terminal arterioles to proximal vessels may contribute to match tissue demands and blood supply during skeletal muscle contraction. Conduction of vasodilatation (CVD) from distal resistance arterioles to the proximal arterioles and feeding arteries during metabolic demand is mediated by intercellular gap junctions in the vascular endothelium. The role of hyperhomocysteinemia (HHcy) in the musculoskeletal system during CVD is unclear. We hypothesize that during HHcy, there is impaired CVD due to decreased expression of endothelial-associated connexins and thus decreased tissue perfusion to the contracting skeletal muscles. METHODS CVD studies were performed in a gluteus maximus muscle preparation of wild-type (C57BL6/J) and CBS-/+ (HHcy) mice using intravital microscopy. Expression of connexins and myostatin protein (an antiskeletal muscle statin) was studied by Western blot and immunohistochemistry methods. Tissue perfusion to acetylcholine was assessed by the laser Doppler technique. RESULTS There was decreased CVD and tissue perfusion in response to acetylcholine in CBS-/+ mice compared to wild-type controls. There was decreased expression of connexins 37, 40 and 43 and increased expression of myostatin in CBS-/+ mice compared to wild-type controls. CONCLUSION Our findings suggest that CVD in skeletal muscle is decreased during HHcy due to decreased expression of gap junction connexins.
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Affiliation(s)
- S Givvimani
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Ky., USA.
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Givvimani S, Kundu S, Narayanan N, Armaghan F, Qipshidze N, Pushpakumar S, Vacek TP, Tyagi SC. TIMP-2 mutant decreases MMP-2 activity and augments pressure overload induced LV dysfunction and heart failure. Arch Physiol Biochem 2013; 119:65-74. [PMID: 23398532 PMCID: PMC3881363 DOI: 10.3109/13813455.2012.755548] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Pressure overload induces cardiac extracellular matrix (ECM) remodelling and results in heart failure. ECM remodelling by matrix metalloproteinases (MMPs) is primarily regulated by their target inhibitors, tissue inhibitor of matrix metalloproteinases (TIMPs). It is known that TIMP-2 is highly expressed in myocardium and is required for cell surface activation of pro-MMP-2. We and others have reported that imbalance between angiogenic growth factors and anti-angiogenic factors results in transition from compensatory cardiac hypertrophy to heart failure. We previously reported the pro-angiogenic role of MMP-2 in cardiac compensation, however, the specific role of TIMP-2 during pressure overload is yet unclear. We hypothesize that genetic ablation of TIMP-2 exacerbates the adverse cardiac matrix remodelling due to lack of pro-angiogenic MMP-2 and increase in anti-angiogenic factors during pressure overload stress and results in severe heart failure. To verify this, ascending aortic banding (AB) was created to mimic pressure overload, in wild type C57BL6/J and TIMP-2-/- (model of MMP-2 deficiency) mice. Left ventricular (LV) function assessed by echocardiography and pressure-volume loop studies showed severe LV dysfunction in TIMP-2-/- AB mice compared to controls. Expression of MMP-2, vascular endothelial growth factor (VEGF) was decreased and expression of MMP-9, anti-angiogenic factors endostatin and angiostatin was increased in TIMP-2-/- AB mice compared with wild type AB mice. Connexins (Cx) are the gap junction proteins that are widely present in the myocardium and play an important role in endothelial-myocyte coupling. Our results showed that expression of Cx 37 and 43 was decreased in TIMP-2-/- AB mice compared with corresponding wild type controls. These results suggest that genetic ablation of TIMP-2 decrease the expression of pro-angiogenic MMP-2, VEGF and increases anti-angiogenic factors that results in exacerbated abnormal ventricular remodelling leading to severe heart failure.
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Affiliation(s)
- S Givvimani
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, KY 40202, USA.
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Givvimani S, Munjal C, Narayanan N, Aqil F, Tyagi G, Metreveli N, Tyagi SC. Hyperhomocysteinemia decreases intestinal motility leading to constipation. Am J Physiol Gastrointest Liver Physiol 2012; 303:G281-90. [PMID: 22595990 PMCID: PMC3423105 DOI: 10.1152/ajpgi.00423.2011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Elevated levels of plasma homocysteine (Hcy) called hyperhomocysteinemia (HHcy) have been implicated in inflammation and remodeling in intestinal vasculature, and HHcy is also known to aggravate the pathogenesis of inflammatory bowel disease (IBD). Interestingly, colon is the pivotal site that regulates Hcy levels in the plasma. We hypothesize that HHcy decreases intestinal motility through matrix metalloproteinase-9 (MMP-9)-induced intestinal remodeling leading to constipation. To verify this hypothesis, we used C57BL/6J or wild-type (WT), cystathionine β-synthase (CBS(+/-)), MMP-9(-/-), and MMP-9(-/-) + Hcy mice. Intestinal motility was assessed by barium meal studies and daily feces output. Plasma Hcy levels were measured by HPLC. Expression of ICAM-1, inducible nitric oxide synthase, MMP-9, and tissue inhibitors of MMPs was studied by Western blot and immunohistochemistry. Reactive oxygen species (ROS) including super oxide were measured by the Invitrogen molecular probe method. Tissue nitric oxide levels were assessed by a commercially available kit. Plasma Hcy levels in the treated MMP-9 group mice were comparable to CBS(+/-) mice. Barium meal studies suggest that intestinal motility is significantly decreased in CBS(+/-) mice compared with other groups. Fecal output-to-body weight ratio was significantly reduced in CBS(+/-) mice compared with other groups. There was significant upregulation of MMP-9, iNOS, and ICAM-1 expression in the colon from CBS(+/-) mice compared with WT mice. Levels of ROS, superoxide, and inducible nitric oxide were elevated in the CBS(+/-) mice compared with other groups. Results suggest that HHcy decreases intestinal motility due to MMP-9-induced intestinal remodeling leading to constipation.
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Affiliation(s)
- S. Givvimani
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Kentucky
| | - C. Munjal
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Kentucky
| | - N. Narayanan
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Kentucky
| | - F. Aqil
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Kentucky
| | - G. Tyagi
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Kentucky
| | - N. Metreveli
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Kentucky
| | - S. C. Tyagi
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Kentucky
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Hari BNV, Dhevendaran K, Narayanan N. Development of Efavirenz nanoparticle for enhanced efficiency of anti-retroviral therapy against HIV and AIDS. BMC Infect Dis 2012. [PMCID: PMC3344724 DOI: 10.1186/1471-2334-12-s1-p7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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McDermott G, Korba E, Mata U, Jaigirdar M, Narayanan N, Boylan J, Conlon N. Should we stop doing blind transversus abdominis plane blocks? Br J Anaesth 2012; 108:499-502. [PMID: 22236911 DOI: 10.1093/bja/aer422] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Any landmark-based regional anaesthetic technique raises two important issues. The first is the accuracy of placement of the needle and thus the local anaesthetic in a 'blind' technique and the second is the potential for damage to adjacent structures. We designed a prospective, blinded study in an adult general surgical population to evaluate with ultrasound the placement of the needle tip and local anaesthetic during transversus abdominis plane (TAP) blocks using the landmark-based 'double-pop' technique. METHODS After induction of general anaesthesia, 36 adult patients had a TAP block performed bilaterally using the standard landmark-based technique. Ultrasonography was then used to record the actual needle position and local anaesthetic spread. The anaesthetist performing the block was blinded to the ultrasound images. RESULTS Thirty-six adult patients were included in the study, which was terminated early due to what was considered an unacceptably high level of peritoneal needle placements. The needle tip and local anaesthetic spread were in the correct plane in only 17 (23.6%) of the injections. In the remaining 55 (76.4%), the needle was in the subcutaneous tissue 1 (1.38%), external oblique muscle 1 (1.38%), plane between the external and internal oblique muscles 5 (6.94%), internal oblique muscle 26 (36.1%), transversus abdominis muscle 9 (12.5%), and peritoneum 13 (18%). CONCLUSIONS We conclude that the needle and local anaesthetic placement using the standard landmark-based approach to the TAP block is inaccurate, and the incidence of peritoneal placement is unacceptably high.
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Affiliation(s)
- G McDermott
- Department of Anaesthesia, St Vincent' s University Hospital, Dublin, Ireland.
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Manoj N, Bakshy K, Narayanan N. Molecular determinants of substrate specificity in a novel SGNH hydrolase. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311080494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Abstract
The antitumour activity of the hydroalcoholic extract of the leaf (PCL) and stem bark (PCB) of Prosopis cineraria (L.) in Swiss albino mice was evaluated against an Ehrlich ascites carcinoma (EAC) tumour model. The activity was assessed using survival time, peritoneal cells, haematological studies, lipid peroxidation, antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, solid tumour mass and in vitro cytotoxicity. PCL and PCB were found to be potent and possessed significant cytotoxicity towards EAC tumour cells.
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Affiliation(s)
- Stellaa Robertson
- Department of Pharmacognosy, Maharaji College of Pharmacy, Chennai 600090, Tamil Nadu, India.
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Poovi G, Dhana leks U, Narayanan N, Neelakanta P. Preparation and Characterization of Repaglinide Loaded Chitosan Polymeric Nanoparticles. ACTA ACUST UNITED AC 2011. [DOI: 10.3923/rjnn.2011.12.24] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Mikhailova D, Narayanan N, Gruner W, Voss A, Senyshyn A, Trots DM, Fuess H, Ehrenberg H. The Role of Oxygen Stoichiometry on Phase Stability, Structure, and Magnetic Properties of Sr2CoIrO6−δ. Inorg Chem 2010; 49:10348-56. [DOI: 10.1021/ic100973p] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D. Mikhailova
- Institute for Complex Materials, IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
- Institute for Materials Science, Technische Universität Darmstadt, Petersenstrasse 23, D-64287, Darmstadt, Germany
| | - N. Narayanan
- Institute for Complex Materials, IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
- Institute for Materials Science, Technische Universität Darmstadt, Petersenstrasse 23, D-64287, Darmstadt, Germany
| | - W. Gruner
- Institute for Complex Materials, IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
| | - A. Voss
- Institute for Complex Materials, IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
| | - A. Senyshyn
- Institute for Materials Science, Technische Universität Darmstadt, Petersenstrasse 23, D-64287, Darmstadt, Germany
| | - D. M. Trots
- Bavarian Research Institute of Experimental Geochemistry and Geophysics, University of Bayreuth, Universitätsstrasse 30, D-95440, Bayreuth, Germany
| | - H. Fuess
- Institute for Materials Science, Technische Universität Darmstadt, Petersenstrasse 23, D-64287, Darmstadt, Germany
| | - H. Ehrenberg
- Institute for Complex Materials, IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
- Institute for Materials Science, Technische Universität Darmstadt, Petersenstrasse 23, D-64287, Darmstadt, Germany
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Narayanan N, Conlon N, Seigne P. Acute methaemoglobinaemia secondary to intentional dapsone overdose. Ir Med J 2010; 103:285. [PMID: 21186757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
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Kumaravelrajan R, Narayanan N, Suba V, Bhaskar K. Simultaneous delivery of Nifedipine and Metoprolol tartarate using sandwiched osmotic pump tablet system. Int J Pharm 2010; 399:60-70. [PMID: 20696225 DOI: 10.1016/j.ijpharm.2010.08.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Revised: 07/22/2010] [Accepted: 08/02/2010] [Indexed: 11/19/2022]
Abstract
The sandwiched osmotic tablet system that could deliver Nifedipine and Metoprolol tartarate simultaneously for extended period of time was developed in order to reduce the problems associated with multidrug therapy of hypertension. This system composed of a middle push layer and attached drug layers of Nifedipine and Metoprolol. The advantage of the sandwiched osmotic tablet system over the commercialized push-pull osmotic tablet system is its simplicity of preparation, as the surface identification was avoided. Polyethylene oxide 600,000 and 8,000,000 g/mole were used as thickening agent of drug layer and the expandable hydrogel of push layer, respectively. It has been observed that amount of polyethylene oxide (PEO) and KCL of the drug and push layer had profound influence on Nifedipine and Metoprolol release. Further, the release of drugs was optimized by the size of the delivery orifice, level of plasticizer and membrane thickness. The optimal osmotic pump tablet was found to deliver both drugs at a rate of approximately zero order for up to 16 h independent of pH and agitational intensity, but dependent on the osmotic pressure of the release media. The formulations were found to be stable after 3 months of accelerated stability studies. Prediction of steady-state levels showed the plasma concentrations of Nifedipine and Metoprolol to be within the desired range. Further sandwiched system had a good sustained effect in comparison with the conventional product. Hence the prototype design of the system could be applied to other combinations of drugs used for cardiovascular diseases, diabetes, etc.
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Affiliation(s)
- R Kumaravelrajan
- Department of Pharmaceutics, CL Baid Metha College of Pharmacy, Chennai, Tamil Nadu, India.
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Baskar GV, Narayanan N, Gaikwad R, Abdul S. Formulation and Evaluation of Gastro-retentive Floating Multi-particulate System of Metoprolol Tartarate. TROP J PHARM RES 2010. [DOI: 10.4314/tjpr.v9i2.53707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Muthu R, Narayanan N, Subramanian C. On k-intersection edge colourings. Discuss Math Graph Theory 2009; 29:411. [DOI: 10.7151/dmgt.1456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
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Abstract
The purpose of this study was to investigate the nasal absorption of progesterone from carbopol-based nasal gels in rabbits. Progesterone nasal gels were prepared by dispersing carbopol 974 (1%, 1.5%, and 2%) in distilled water followed by addition of progesterone/progesterone-beta cyclodextrin complex dissolved in propylene glycol then neutralization. The potential use of beta cyclodextrin (CD) as nasal absorption enhancer by simple addition, as a physical mixture and as a complex with progesterone was investigated. The absolute bioavailability of progesterone from nasal gels in rabbits was studied by estimating the serum progesterone level by competitive solid-phase enzyme immunoassay in comparison to intravenous injection. The carbopol gel formulations produced a significant increase in bioavailability. CD complex promotes the nasal absorption of progesterone from carbopol gels as compared with gels where the CD is added by simple addition and gels which do not contain CD. This method of addition of CD as an inclusion complex in the gels could be considered as a preferred platform in nasal drug administration.
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Affiliation(s)
- Grace Rathnam
- Department of Pharmaceutics, C.L. Baid Metha College of Pharmacy, Thorapakkam, Chennai 600097, India.
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Ehrenberg H, Mikhailova D, Narayanan N, Fuess H, Ritter C, Trots D, Senyshyn A, Oswald S, Gruner W, Voss A. The effect of structural and compositional details on physical properties of new double perovskites. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308098243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Narayanan N, Chou C. Physiological Improvement to Enhance Escherichia coli Cell-Surface Display via Reducing Extracytoplasmic Stress. Biotechnol Prog 2008; 24:293-301. [DOI: 10.1021/bp0702121] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Muthu R, Narayanan N, Subramanian CR. Acyclic Edge Colouring of Outerplanar Graphs. Algorithmic Aspects in Information and Management 2007:144-152. [DOI: 10.1007/978-3-540-72870-2_14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
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Senthilvel G, Austin A, Jegadeesan M, Thirugnana P, Narayanan N, Viswanatha S. Effect of a Polyherbal Formulation (Diarun plus) on the Glycemic Status Modified by Physiological Means in Non-diabetic Mice and Rats. INT J PHARMACOL 2007. [DOI: 10.3923/ijp.2007.175.178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Zhou J, Sims S, Narayanan N. A142. Depressed Ca2+ cycling by cardiac sarcoplasmic reticulum (SR) following chronic blockade of L-type Ca2+ channels. J Mol Cell Cardiol 2006. [DOI: 10.1016/j.yjmcc.2006.03.424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Xu A, Jiang M, Narayanan N. A16. Calmodulin triggers Cardiac SR Ca2+ pump function by disrupting Ca2+-ATPase-phopholamban interaction. J Mol Cell Cardiol 2006. [DOI: 10.1016/j.yjmcc.2006.03.356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Jiang M, Xu A, Narayanan N. A12. Thyroid hormone down regulates the expression and function of CaM kinase II in the rabbit heart. J Mol Cell Cardiol 2006. [DOI: 10.1016/j.yjmcc.2006.03.326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Sathish V, Xu A, Karmazyn M, Sims SM, Narayanan N. Mechanistic basis of differences in Ca2+ -handling properties of sarcoplasmic reticulum in right and left ventricles of normal rat myocardium. Am J Physiol Heart Circ Physiol 2006; 291:H88-96. [PMID: 16461368 DOI: 10.1152/ajpheart.01372.2005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study investigated Ca2+ -cycling properties of sarcoplasmic reticulum (SR) in right ventricle (RV) and left ventricle (LV) of normal rat myocardium. Intracellular Ca2+ transients and contractile function were monitored in freshly isolated myocytes from RV and LV. SR in RV displayed nearly fourfold lower rates of ATP-energized Ca2+ uptake in vitro than SR of LV. The Ca2+ concentration required for half-maximal activation of Ca2+ transport was nearly twofold higher in SR of RV. The lower Ca2+ -sequestering activity of SR in RV was accompanied by a matching decrement in Ca2+ -induced phosphoenzyme formation during the catalytic cycle of the Ca2+ -pumping ATPase (SERCA2). Western immunoblot analysis showed that protein levels of Ca2+ -ATPase and its inhibitor phospholamban (PLN) were only approximately 15% lower in SR of RV than in SR of LV. Coimmunoprecipitation experiments revealed that PLN-bound, functionally inert Ca2+ -ATPase molecules in SR of RV greatly exceed (> 50%) that in SR of LV. Endogenous Ca2+/calmodulin-dependent protein kinase-mediated phosphorylation of SR substrates did not abolish the huge disparity in SR Ca2+ pump function between RV and LV. Intracellular Ca2+ transients, evoked by electrical field stimulation, were significantly prolonged in RV myocytes compared with LV myocytes, mainly because of slow decay of intracellular Ca2+ concentration. The slow decay of intracellular Ca2+ concentration in RV and consequent decrease in the speed of RV relaxation may promote temporal synchrony of the end of diastole in RV and LV. The preponderance of functionally silent SR Ca2+ pumps in RV reflects a higher diastolic reserve required to protect and maintain RV function in the face of a sudden rise in afterload or resistance in the pulmonary circulation.
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Affiliation(s)
- V Sathish
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada N6A 5C1
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Jiang M, Xu A, Jones DL, Narayanan N. Coordinate downregulation of CaM kinase II and phospholamban accompanies contractile phenotype transition in the hyperthyroid rabbit soleus. Am J Physiol Cell Physiol 2004; 287:C622-32. [PMID: 15115706 DOI: 10.1152/ajpcell.00352.2003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study investigated the effects of l-thyroxine-induced hyperthyroidism on Ca2+/calmodulin (CaM)-dependent protein kinase (CaM kinase II)-mediated sarcoplasmic reticulum (SR) protein phosphorylation, SR Ca2+pump (Ca2+-ATPase) activity, and contraction duration in slow-twitch soleus muscle of the rabbit. Phosphorylation of Ca2+-ATPase and phospholamban (PLN) by endogenous CaM kinase II was found to be significantly lower (30–50%) in soleus of the hyperthyroid compared with euthyroid rabbit. Western blotting analysis revealed higher levels of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) 1 (∼150%) Ca2+pump isoform, unaltered levels of SERCA2 Ca2+pump isoform, and lower levels of PLN (∼50%) and δ-, β-, and γ-CaM kinase II (40 ∼ 70%) in soleus of the hyperthyroid rabbit. SR vesicles from hyperthyroid rabbit soleus displayed approximately twofold higher ATP-energized Ca2+uptake and Ca2+-stimulated ATPase activities compared with that from euthyroid control. The Vmaxof Ca2+uptake (in nmol Ca2+·mg SR protein−1·min−1: euthyroid, 818 ± 73; hyperthyroid, 1,649 ± 90) but not the apparent affinity of the Ca2+-ATPase for Ca2+(euthyroid, 0.97 ± 0.02 μM, hyperthyroid, 1.09 ± 0.04 μM) differed significantly between the two groups. CaM kinase II-mediated stimulation of Ca2+uptake by soleus muscle SR was ∼60% lower in the hyperthyroid compared with euthyroid. Isometric twitch force of soleus measured in situ was significantly greater (∼36%), and the time to peak force and relaxation time were significantly lower (∼30–40%), in the hyperthyroid. These results demonstrate that thyroid hormone-induced transition in contractile properties of the rabbit soleus is associated with coordinate downregulation of the expression and function of PLN and CaM kinase II and selective upregulation of the expression and function of SERCA1, but not SERCA2, isoform of the SR Ca2+pump.
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Affiliation(s)
- M Jiang
- Dept. of Physiology and Pharmacology, Health Science Center, The University of Western Ontario, London, Ontario, Canada N6A 5C1
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Ramadass T, Narayanan N, Kulkarni GN, Geetha B, Neelamekhem TK. An unusual complication of Thyroid Surgery and its management. Indian J Otolaryngol Head Neck Surg 2001; 53:323-5. [PMID: 23119838 PMCID: PMC3450478 DOI: 10.1007/bf02991563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Stricture oesophagus is an unusal complication of thyroid surgery. There is only one case of such nature recorded in literature, which shows that the surgeon who operated may not have had any previous experience of head and neck surgery. Locating the stricture was difficult, more so planning the treatment modality was problematic. Informed consent for oesophagectomy with gastric pull through was taken. However when we explored the neck the stricture was seen just below the level of pyriform sinus. It could be successfully excised without end to end anastomosis.
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Affiliation(s)
- T Ramadass
- Head of Department of ENT, Apollo Hospitals, 21, Greams Lane off Greams Road, Chennai - 600 006, India
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Abstract
To decipher the mechanism(s) underlying glucocorticoid action on cardiac contractile function, this study investigated the effects of adrenalectomy and dexamethasone treatment on the contents of sarcoplasmic reticulum (SR) Ca(2+)-cycling proteins, their phosphorylation by endogenous Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II), and SR Ca(2+) sequestration in the rat myocardium. Cardiac SR vesicles from adrenalectomized rats displayed significantly diminished rates of ATP-energized Ca(2+) uptake in vitro compared with cardiac SR vesicles from control rats; in vivo administration of dexamethasone to adrenalectomized rats prevented the decline in SR function. Western immunoblotting analysis showed that the relative protein amounts of ryanodine receptor/Ca(2+)-release channel, Ca(2+)-ATPase, calsequestrin, and phospholamban were neither diminished significantly by adrenalectomy nor elevated by dexamethasone treatment. However, the relative amount of SR-associated CaM kinase II protein was increased 2.5- to 4-fold in dexamethasone-treated rats compared with control and adrenalectomized rats. Endogenous CaM kinase II activity, as judged from phosphorylation of ryanodine receptor, Ca(2+)-ATPase, and phospholamban protein, was also significantly higher (50--80% increase) in the dexamethasone-treated rats. The stimulatory effect of CaM kinase II activation on Ca(2+) uptake activity of SR was significantly depressed after adrenalectomy and greatly enhanced after dexamethasone treatment. These findings identify the SR as a major target for glucocorticoid actions in the heart and implicate modification of the SR CaM kinase II system as a component of the mechanisms by which dexamethasone influences SR Ca(2+)-cycling and myocardial contraction.
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Affiliation(s)
- M K Rao
- Department of Physiology, The University of Western Ontario, London, Ontario, Canada N6A 5C1
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Abstract
Lipoma with osseous metaplasia of the external ear is an uncommon and has not been reported so far in Medline search for 30 years. The diagnosis was confirmed only after excision biopsy of the lesion. We report this case for its rarity.
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Affiliation(s)
- T Ramadass
- Department of ENT and Head and Neck Surgery, Apollo Hospitals, Chennai
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Abstract
The effect of Ca2+ on the conversion of cortisol to its inert metabolite cortisone, the reaction catalyzed by the microsomal enzyme 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2), was investigated in human placental microsomes. Placental microsomal 11beta-HSD2 activity, as determined by the rate of conversion of cortisol to cortisone, was inhibited up to 50% by increasing free Ca2+ concentrations from 22 to 268 nM. The Ca2+-induced inhibition was reversible since chelation of endogenous Ca2+ with EGTA increased 11beta-HSD2 activity up to 200%. Ca2+ decreased the maximal velocity (Vmax) of the 11beta-HSD2 catalyzed conversion of cortisol to cortisone without altering the Km of 11beta-HSD2 for cortisol, indicating that Ca2+ modulates the catalytic efficiency rather than the substrate binding of 11beta-HSD2. Moreover, the Ca2+-induced inhibition does not appear to involve altered cofactor (NAD+) binding since the inhibition of microsomal 11beta-HSD2 activity by a sub-maximal concentration of free Ca2+ was not overcome by increasing the concentration of NAD+. These findings in the microsomes were then extended to an intact cell system, JEG-3 cells, an established model for human placental trophoblasts. In these cells, an increase in cytosolic free Ca2+ concentration ([Ca2+]i) elicited by a known physiological stimulus, PGF(2alpha), was accompanied by a 40% decrease in the level of 11beta-HSD2 activity. Furthermore, the PGF(2alpha)-induced inhibition of 11beta-HSD2 activity was abrogated when increases in [Ca2+]i were blocked with the intracellular Ca2+ chelator, BAPTA. Collectively, these results demonstrate for the first time that Ca2+ inhibits human placental 11beta-HSD2 activity by a post-translational mechanism not involving substrate or cofactor binding.
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Affiliation(s)
- D B Hardy
- CIHR Group in Fetal and Neonatal Health and Development, Lawson Health Research Institute, St. Joseph's Health Care of London, Department of Obstetrics and Gynaecology, University of Western Ontario, 268 Grosvenor Street, London, Ontario, Canada
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Abstract
Gastroesophageal reflux disease (GERD) is a disease that has come to limelight in the rreent past to account for various ear, nose and throat disorders. Fifty patients from my outpatient department, presenting with chronic dry paroxysmal cough, choking spells, globus sensation, voice change, burning throat syndrome, dysphagia were evaluated, with both invasive and non-invasive techniques like Fibreoptic Nasoendoscopy, Nuclear Scintigraphy with technetium, Barium swallow, sans pH monitoring which is an expensive and laborious method.We have shown evidence of GER with help of Nasoendoscopy, which revealed posterior laryngitis, erythema of arytenoids and interarytenoid oedema. This is corroborated with Scintigraphy done in Nuclear Medicine department, which is our gold standard for labelling the cases as GERD. Basing on the investigations, we have treated successfully fifty cases with medical treatment consisting of H2 Hockers, proton pump inhibitors and microlaryngeal surgery wherever necessary. In this article we are discussing the various symptoms, the fifty patients complained of, and how we are able to pinpoint the diagnosis and the modality we adopted with the facilities available, and also a brief review of literature.
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Affiliation(s)
- T Ramadass
- Department of ENT and Head and Neck Surgery, Apollo Hospitals, Greams Lane Off Greams Road, 600 006 Chennai
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Lee SH, Johnson JD, Walsh MP, Van Lierop JE, Sutherland C, Xu A, Snedden WA, Kosk-Kosicka D, Fromm H, Narayanan N, Cho MJ. Differential regulation of Ca2+/calmodulin-dependent enzymes by plant calmodulin isoforms and free Ca2+ concentration. Biochem J 2000. [PMID: 10926857 DOI: 10.1042/0264-6021:3500299] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/24/2023]
Abstract
Multiple calmodulin (CaM) isoforms are expressed in plants, but their biochemical characteristics are not well resolved. Here we show the differential regulation exhibited by two soya bean CaM isoforms (SCaM-1 and SCaM-4) for the activation of five CaM-dependent enzymes, and the Ca(2+) dependence of their target enzyme activation. SCaM-1 activated myosin light-chain kinase as effectively as brain CaM (K(act) 1.8 and 1.7 nM respectively), but SCaM-4 produced no activation of this enzyme. Both CaM isoforms supported near maximal activation of CaM-dependent protein kinase II (CaM KII), but SCaM-4 exhibited approx.12-fold higher K(act) than SCaM-1 for CaM KII phosphorylation of caldesmon. The SCaM isoforms showed differential activation of plant and animal Ca(2+)-ATPases. The plant Ca(2+)-ATPase was activated maximally by both isoforms, while the erythrocyte Ca(2+)-ATPase was activated only by SCaM-1. Plant glutamate decarboxylase was activated fully by SCaM-1, but SCaM-4 exhibited an approx. 4-fold increase in K(act) and an approx. 25% reduction in V(max). Importantly, SCaM isoforms showed a distinct Ca(2+) concentration requirement for target enzyme activation. SCaM-4 required 4-fold higher [Ca(2+)] for half-maximal activation of CaM KII, and 1.5-fold higher [Ca(2+)] for activation of cyclic nucleotide phosphodiesterase than SCaM-1. Thus these plant CaM isoforms provide a mechanism by which a different subset of target enzymes could be activated or inhibited by the differential expression of these CaM isoforms or by differences in Ca(2+) transients.
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Affiliation(s)
- S H Lee
- Department of Biochemistry, Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Chinju 660-701, Republic of Korea
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