Joana Chakraborty
University of Toledo Medical Center
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Featured researches published by Joana Chakraborty.
Urological Research | 2004
Joana Chakraborty; Angela A. Below; Deana Solaiman
Tamm-Horsfall protein (THP) is a glycoprotein present abundantly in human urine. It is localized in the thick ascending limb of the loop of Henle (TAL) and the early distal convoluted tubule (DCT). The rate of urinary excretion of THP has been studied in various diabetic groups. It has been postulated that urinary THP may be a useful marker for renal damage. The aim of this study was to compare directly the immunogold localization of THP in diabetic and control kidney tissue specimens with or without kidney damage. Immunogold labeling was performed on archival tissue samples of 34 diabetic and 18 control human kidneys at the light microscope level. Slides were ranked as having a high, moderate or low degree of reaction. The majority of diabetic samples had a slightly lower degree of THP, while patients with known renal dysfunction had lowest THP. Previous studies have found a decreased excretion of urinary THP in diabetics. Our results show that decreased gold labeling is associated with known renal damage and may indicate damage to the thick ascending limb of the loop of Henle and the early distal convoluted tubule, irrespective of presence or absence of diabetes.
Reproductive Biomedicine Online | 2006
Yigal Gat; Michael Gornish; Uri Navon; Joana Chakraborty; Gil N. Bachar; Izhar Ben-Shlomo
Varicocele is considered a predominantly unilateral left-sided disease. However, since male fertility is preserved with only one healthy testis, infertility perforce represents bilateral testicular dysfunction. It was hypothesized that: (i) right varicocele cannot be diagnosed by palpation and therefore has not been treated in the past by the traditional treatment, and (ii) right varicocele causes impaired oxygen supply in the right testicular microcirculation, leading to germ cell degeneration. This study performed venographies of both right and left internal spermatic veins during the treatment of 840 infertile men with varicocele and analysed the results using tools of fluid mechanics. Histopathology of the right testis revealed stagnation of blood flow and degenerative changes attributed to lack of adequate oxygenation in all testicular cell types. Right varicocele was found in the vast majority of the patients. We found that due to the destruction of one-way valves, pathologic hydrostatic pressure is produced in the testicular venous microcirculatory system about five times higher than normal, exceeding arteriolar pressure. The pressure gradient between the arterioles and venules in the testicular tissue is therefore reversed, leading to persistent hypoxia. Right varicocele, although undetected, is prevalent in infertile men with varicocele, hence only bilateral occlusion of the internal spermatic veins, including the associated bypasses, eliminating the pathologic hydrostatic pressure will lead to resumption of arterial blood flow in the testicular microcirculation.
Journal of Immigrant Health | 2003
Keri Fitzgerald; Joana Chakraborty; Trupti Shah; Sadik A. Khuder; Joan Duggan
The rate of HIV infection in the migrant farm worker community is 10 times the national average. A survey was conducted of 106 female migrant farm workers in rural Northwest Ohio to assess HIV knowledge. The average participants age was 28.7 years, 78 spoke Spanish, and 47 had an ≤8th- grade education. Fifty-six women received their information on HIV/AIDS from television. Eighty-seven women identified sexual contact as the major source of HIV transmission and 54 women identified the combination of sex, use of needles, and blood contact as the important routes. Sixty-nine women identified both homosexual and heterosexual intercourse as risk factors. Only 58 women identified perinatal infection as a route of HIV transmission and 59 women knew that treatment was available to prevent perinatal transmission. Although the majority of women had a good general knowledge of HIV transmission, further prevention education on perinatal transmission is needed among this population.
Urology | 1994
Mary Grist; Joana Chakraborty
Abstract Objectives. The specific goal of this study was to establish a simple histochemicaltechnique by which the glycosaminoglycan (GAG) lining in the rabbit bladder can be routinely identified. Methods. Rabbit bladder tissues were fixed in zinc formal, 10% neutral buffered formalin (NBF), 20% NBF, 40% NBF, 2% calcium acetate in 10% NBF, 2% sodium acetate in 10% NBF, 1 % cetylpyridinium chloride in 10% NBF, 80% alcohol, histochoice, and 2.5% glutaraldehyde in 0.1 M cacodylate buffer. The following histochemical staining was used: mucicarmine/metanil yellow, colloidal iron, deamination followed by colloidal iron, periodic acid-Schiff, saponification followed by colloidal iron, Alcian blue (AB) at variable pH values, combined aldehyde-fuchsin/AB, performic acid/AB, AB/Alcian yellow, high temperature (60°C) methylation/saponification/AB, and AB/nuclear fast red at pH 5.8 with critical electrolyte concentrations with or without deamination. Results. AB with sodium acetate buffer at pH 5.8 containing 0.6 M or 0.8 M magnesium chloride (MgCl 2 ) showed a well-defined thin GAG lining on the surface of the urothelium, whereas histochemical staining used by previous investigators showed only patchy distribution. There was no observable difference due to the gender, fixative, or region of the bladder from which the tissue was obtained. Conclusions. A very thin lining of GAG exists in the rabbit bladder which can be localized by AB in sodium acetate buffer at pH 5.8 containing 0.6 M or 0.8 M MgC1 2 but not by conventional histochemical techniques. This method now can be applied to answer many questions regarding urothelial function.
Viral Immunology | 2001
Stacie Clark; Joan Duggan; Joana Chakraborty
The ts1 murine leukemia virus produces an immunodeficiency state in mice that parallels human immunodeficiency virus (HIV) infection in humans. Other murine leukemia viruses, such as LP-BM5 used in the murine acquired immune deficiency virus (MAIDS) model, have been studied extensively as a small animal model for HIV research, but lack many key similarities to HIV. Mice infected with ts1, however, utilize CD4 target cells for infection, undergo neuronal loss and demyelination, and develop clinical immunodeficiency. These features make this retrovirus in many ways an ideal candidate for a small animal model for HIV research. In this review article, the early development, the molecular and clinical pathogenesis of both the ts1 mutant of the Moloney murine leukemia virus and LP-BM5 are examined. Based on an extensive evaluation of the literature on LP-BM5 and ts1, it is concluded that the ts1 virus may serve as a better animal model to human retrovirus infection.
Aids Care-psychological and Socio-medical Aspects of Aids\/hiv | 2009
Joan Duggan; Ann Locher; Brian N. Fink; Chrystal Okonta; Joana Chakraborty
Abstract The use of highly active antiretroviral therapy (HAART) has decreased morbidity and mortality for people living with HIV/AIDS, but adherence to HAART is a critical factor in successful treatment. Adherence to medication is a complex and poorly understood behavior. A survey was undertaken to evaluate subjective correlates of adherence and non-adherence based on previously distilled themes from a qualitative study of adherence. A 60-question survey was completed by patients in the outpatient clinic setting regarding demographics, CD4 cell count, viral load, adherence, and screening questions about medication usage and attitudes toward HIV. Ninety-eight adherent and 34 non-adherent patients completed the survey. After logistic regression analysis, several questions appeared to be the main predictors of non-adherence: Have you ever thought of having HIV as a “punishment?” Do you feel that your medicines are hard to take? Do you believe the medicines for HIV that you take are working for you? These questions may be helpful in the development of a clinically useful screening tool to assess patients at risk for non-adherence.
Andrologia | 2010
Y. Gat; M. Gornish; A. Perlow; Joana Chakraborty; U. Levinger; I. Ben-Shlomo; F. Pasqualotto
Sertoli‐cell‐only (SCO) syndrome, or germ cell aplasia, is diagnosed on testicular biopsy when germ cells are seen to be absent without histological impairment of Sertoli or Leydig cells. It is considered a situation of irreversible infertility. Recent studies have shown that varicocele, a bilateral disease, causes hypoxia in the testicular microcirculation. Destruction of one‐way valves in the internal spermatic veins (ISV) elevates hydrostatic pressure in the testicular venules, exceeding the pressure in the arteriolar system. The positive pressure gradient between arterial and venous system is reversed, causing hypoxia in the sperm production site. Sperm production deteriorates gradually, progressing to azoospermia. Our prediction was that, if genetic problems are excluded, SCO may be the final stage of longstanding hypoxia which deteriorates sperm production in a progressive process over time. This would indicate that SCO is not always an independent disease entity, but may represent deterioration of the testicular parenchyma beyond azoospermia. Our prediction is confirmed by histology of the seminiferous tubules demonstrating that SCO is associated with extensive degenerative ischaemic changes and destruction of the normal architecture of the sperm production site. Adequate treatment of bilateral varicocele by microsurgery or by selective sclerotherapy of the ISV resumes, at least partially, the flow of oxygenated blood to the sperm production site and restored sperm production in 4 out of 10 patients. Based on our findings the following statements can be made: (i) SCO may be related in part of the cases to persistent, longstanding testicular parenchymal hypoxia; (ii) germ cells may still exist in other areas of the testicular parenchyma; and (iii) if genetic problems are excluded, adequate correction of the hypoxia may restore very limited sperm production in some patients.
Journal of Occupational and Environmental Medicine | 1996
Krishnan Allampallam; Joana Chakraborty; Kallol K. Bose; John Robinson
Although flexor-retinaculum (FR) release provides dramatic relief from carpal tunnel syndrome (CTS), the role of this ligament in CTS is not well understood. We have adopted a unique approach to study the cellular pathogenesis of CTS by establishing a method for the culture of cells of FR from subjects with and without CTS. The cultured cells were characterized by light, immunofluorescence, electron microscopy, Western blot analysis, and growth studies. Two main differences between the CTS and control cells included a faster growth rate and an altered fine morphology that reveals the contractile nature of the CTS cells. It is possible that the presence of these contractile cells in FR is responsible for increasing the contractility of the FR, leading to a decrease in the volume of the carpal tunnel, thus exerting pressure on the median nerve and triggering CTS.
Journal of Occupational and Environmental Medicine | 2000
Krishnan Allampallam; Joana Chakraborty; John Robinson
The effects of ascorbic acid and various growth factors on the proliferation rate and collagen metabolism were studied in cells from the flexor retinaculum of individuals with carpal tunnel syndrome (FR-CTS) and without carpal tunnel syndrome (FR control) and in human dermal fibroblasts. Ascorbic acid and four growth factors, including basic fibroblast growth factor, transforming growth factor, platelet-derived growth factor, and epidermal growth factors, were used. Ascorbic acid stimulates type I collagen production more in FR control than in FR-CTS. Growth factor treatment resulted in the following responses by the cells: (1) a higher mitogenic response than in the control cells; (2) a higher stimulation of type III collagen production and a lower stimulation of type I collagen production in CTS cells as compared with control cells; and (3) more alpha 2 (I) than alpha 1 (I) collagen production in CTS cells, unlike in control cells. We concluded that cells of the FR from individuals with CTS are physiologically altered.
Journal of Diabetes and Its Complications | 1999
Angela A. Below; Joana Chakraborty; Sadik H. Khuder; Gregory D. Haselhuhn
Tamm-Horsfall protein (THP), a glycoprotein produced in the thick ascending limb (TAL) and the early distal convoluted tubule (DCT), is normally excreted in large amounts in urine. Urinary THP may be a useful marker for renal damage. The goal of this research project was to determine the THP excretion in control and diabetic post-menopausal women. Twenty-four hour urine samples were collected from 19 controls and 19 diabetic patients (11 non-insulin dependent diabetic mellitus (non-IDDM) patients, and 8 insulin dependent diabetic mellitus (IDDM) patients). Polyacrylamide gel electrophoresis (PAGE), Western blotting, and enzyme linked immunosorbent assay (ELISA) methods were used. It was determined that urinary THP concentrations were significantly decreased in patients with IDDM compared to patients with non-IDDM and controls. In conclusion, laboratory quantitation of urinary THP may be a useful indicator of cellular abnormalities such as reduced protein (THP) synthesis of the cells of the TAL and early DCT in some IDDM patients.