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Muralidhar S. The Legacy of the Life and Work of Lotika Sarkar. Indian Journal of Gender Studies 2022. [DOI: 10.1177/09746862221082174] [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: 11/16/2022]
Abstract
Based on a talk by the author, the article seeks to sketch the work and contribution of Professor Lotika Sarkar, the first woman law teacher of the Delhi University. A much sought after teacher, with a progressive outlook, Professor Sarkar mentored several generations of law scholars, teachers and judges. The article speaks of Professor Sarkar’s seminal contribution as member of the Committee on the Status of Women in India. Her chapter on ‘women and the law’ formed a significant part of the Committee’s 1975 report. Professor Sarkar joined three other eminent law teachers in penning an Open Letter to the Chief Justice of India, on September 16, 1979, in the wake of the Tukaram case. This letter paved the way for significant changes in law relating to custodial rape. The issues that Professor Sarkar worked on are of contemporary relevance to any serious legal scholar looking for a reference point, and the right questions to ask.
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Affiliation(s)
- S. Muralidhar
- Chief Justice, High Court of Orissa, Cuttack, Odisha, India
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2
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Muralidhar S, Khymyn R, Awad AA, Alemán A, Hanstorp D, Åkerman J. Femtosecond Laser Pulse Driven Caustic Spin Wave Beams. Phys Rev Lett 2021; 126:037204. [PMID: 33543954 DOI: 10.1103/physrevlett.126.037204] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 09/22/2020] [Accepted: 01/07/2021] [Indexed: 06/12/2023]
Abstract
Controlling the directionality of spin waves is a key ingredient in wave-based computing methods such as magnonics. In this Letter, we demonstrate this particular aspect by using an all-optical pointlike source of continuous spin waves based on frequency comb rapid demagnetization. The emitted spin waves contain a range of k vectors and by detuning the applied magnetic field slightly off the ferromagnetic resonance (FMR), we observe X-shaped caustic spin wave patterns at 70° propagation angles as predicted by theory. When the harmonic of the light source approaches the FMR, the caustic pattern gives way to uniaxial spin wave propagation perpendicular to the in-plane component of the applied field. This field-controlled propagation pattern and directionality of optically emitted short-wavelength spin waves provide additional degrees of freedom when designing magnonic devices.
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Affiliation(s)
- S Muralidhar
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - R Khymyn
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - A A Awad
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - A Alemán
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - D Hanstorp
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - J Åkerman
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
- Materials and Nano Physics, School of Engineering Sciences, KTH Royal Institute of Technology, Electrum 229, 164 40 Kista, Sweden
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Nguyen NUN, Canseco DC, Xiao F, Nakada Y, Li S, Lam NT, Muralidhar S, Savla JJ, Hill JA, Wang Z, Ahmed MS, Hubbi M, Menendez-Montes I, Moon J, Ali SR, Villalobos E, Elhelaly WM, Thet S, Tan WLW, Anene-Nzelu CG, Foo R, Jagoree R, Cyert MS, Rothermel BA, Sadek HA. Abstract MP161: A Calcineurin-hoxb13 Axis Regulates Growth Mode of Mammalian Cardiomyocytes. Circ Res 2020. [DOI: 10.1161/res.127.suppl_1.mp161] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A major factor in the progression to heart failure in humans is the inability of the adult heart to repair itself after injury. Our group recently demonstrated that the early postnatal mammalian heart is capable of regeneration following injury through proliferation of preexisting cardiomyocytes1,2. We recently also showed that Meis1, a TALE family homeodomain transcription factor, translocates to cardiomyocyte nuclei shortly after birth and mediates postnatal cell cycle arrest3. Here we report that Hoxb13 acts as a Meis1 cofactor in postnatal cardiomyocytes. Cardiomyocyte-specific deletion of Hoxb13 can both extend the postnatal window of cardiomyocyte proliferation and reactivate cardiomyocyte cell cycle in the adult heart. Moreover, adult Meis1/Hoxb13 double knockout hearts display widespread cardiomyocyte mitosis, sarcomere disassembly and an improvement in left ventricular systolic function following myocardial infarction both by echocardiography and MRI. ChIP-seq analysis demonstrates that Meis1 and Hoxb13 act cooperatively to regulate cardiomyocyte maturation and cell cycle. Finally, we show that the calcium-activated protein phosphatase calcineurin dephosphorylates Hoxb13 at serine-204 (S204), resulting in its nuclear localization and cell cycle arrest. Collectively, these results demonstrate that Meis1 and Hoxb13 act cooperatively to regulate cardiomyocyte maturation and proliferation and provide mechanistic insights into the link between hyperplastic and hypertrophic growth of cardiomyocytes.
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Affiliation(s)
| | | | - Feng Xiao
- UT Southwestern Med Cntr, Dallas, TX
| | - Yuji Nakada
- Univ of Alabama at Birmingham, Birmingham, AL
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- Cardiovascular Rsch Institute, Singapore
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Fulara H, Zahedinejad M, Khymyn R, Awad AA, Muralidhar S, Dvornik M, Åkerman J. Spin-orbit torque-driven propagating spin waves. Sci Adv 2019; 5:eaax8467. [PMID: 31799403 PMCID: PMC6868678 DOI: 10.1126/sciadv.aax8467] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 08/27/2019] [Indexed: 05/24/2023]
Abstract
Spin-orbit torque (SOT) can drive sustained spin wave (SW) auto-oscillations in a class of emerging microwave devices known as spin Hall nano-oscillators (SHNOs), which have highly nonlinear properties governing robust mutual synchronization at frequencies directly amenable to high-speed neuromorphic computing. However, all demonstrations have relied on localized SW modes interacting through dipolar coupling and/or direct exchange. As nanomagnonics requires propagating SWs for data transfer and additional computational functionality can be achieved using SW interference, SOT-driven propagating SWs would be highly advantageous. Here, we demonstrate how perpendicular magnetic anisotropy can raise the frequency of SOT-driven auto-oscillations in magnetic nanoconstrictions well above the SW gap, resulting in the efficient generation of field and current tunable propagating SWs. Our demonstration greatly extends the functionality and design freedom of SHNOs, enabling long-range SOT-driven SW propagation for nanomagnonics, SW logic, and neuromorphic computing, directly compatible with CMOS technology.
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Affiliation(s)
- H. Fulara
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - M. Zahedinejad
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
- NanOsc AB, Electrum 229, 164 40 Kista, Sweden
| | - R. Khymyn
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - A. A. Awad
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
- NanOsc AB, Electrum 229, 164 40 Kista, Sweden
| | - S. Muralidhar
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - M. Dvornik
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
- NanOsc AB, Electrum 229, 164 40 Kista, Sweden
| | - J. Åkerman
- Physics Department, University of Gothenburg, 412 96 Gothenburg, Sweden
- NanOsc AB, Electrum 229, 164 40 Kista, Sweden
- Material and Nanophysics, School of Engineering Sciences, KTH Royal Institute of Technology, Electrum 229, 164 40 Kista, Sweden
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Xiao F, Savla J, Cardoso AC, Periera AM, Muralidhar S, Canseco D, Sadek HA. Abstract 425: Role of MLF1 in Cardiomyocyte Cell Cycle Regulation. Circ Res 2019. [DOI: 10.1161/res.125.suppl_1.425] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The neonatal mammalian heart is capable of significant regeneration after cardiac injury. However, that ability is lost in the early postnatal period, coinciding with the development of cardiomyocyte cell cycle arrest. Myeloid leukemia factor 1 (MLF1) is a protein expressed in hematopoietic cells, skeletal muscle and cardiac muscle. In hematopoietic cells, MLF1 is thought to be a negative cell cycle regulator, possibly acting through a p53-dependent mechanism. However, the role of MLF1 in the cardiovascular system is not well understood. Here, we describe MLF1 as a regulator of cardiomyocyte cell cycle progression. We first examined the expression pattern of MLF1 in neonatal mouse heart. MLF1 protein specifically expresses in the nucleus, and the expression level increases from P1 to P7 as revealed by quantitative PCR and Western Blot. To elucidate a potential role of Mlf1 in cardiomyocyte proliferation, we silenced Mlf1 in neonatal rat ventricle myocytes (NRVMs) which showed increased cardiomyocyte proliferation by staining with a mitosis marker phospho-Histone 3 (pH3). Then we generated an inducible cardiac-specific Mlf1 knockout mouse model and assessed for the prolongation of the proliferative window by echocardiography, cell size analysis, and immunostaining for cell cycle markers. Staining the Mlf1 KO hearts with proliferation markers, pH3 to determine mitosis and Aurora B kinase to determine cytokinesis, indicated that deletion of Mlf1 resulted in increased cardiomyocyte proliferation. It also showed improvement in left ventricular systolic function following myocardial infarction by echocardiography. In contrast, overexpression of MLF1 in heart showed decreased cardiac function as quantified by ejection fraction. These results identify MLF1 as a negative cell cycle regulator of cardiomyocyte proliferation.
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Affiliation(s)
- Feng Xiao
- UT Southwestern Med Cntr, Dallas, TX
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Patel KH, Reddy AVG, Eachempati K, Muralidhar S, Jungele A. A Patient with Osteoarthritis Knee and Prior Patella Fracture: Single Stage Fixation and Total Knee Arthroplasty: A Case Report. J Orthop Case Rep 2018; 8:67-70. [PMID: 29854698 PMCID: PMC5974682 DOI: 10.13107/jocr.2250-0685.1004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Introduction: Osteoarthritis knee associated with periarticular fractures (femur, tibia, or patella) in geriatric patients is a treatment challenge for orthopedic surgeon. In geriatric patient, early mobilization is key for a better outcome and to prevent immobilization related complications. Hence, this case report is important for all orthopedic surgeons. Case Report: We had a 65-year-old male patient who came for the treatment ofhis patella fracture and deformity ofboth knees. Conclusion: Elderly patients who sustained a patella fracture can be treated with single stage primary total knee replacement and fixation of patella fracture. There is no need for two stage surgery. Rehabilitation and pain relief along with mobilization is better with single stage surgery.
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Affiliation(s)
- Krunal H Patel
- Department of Orthopedics, Sunshine Hospitals Sunshine Hospitals, Secunderabad, Telangana, India
| | - A V Guarava Reddy
- Department of Orthopedics, Sunshine Hospitals Sunshine Hospitals, Secunderabad, Telangana, India
| | | | - S Muralidhar
- Department of Orthopedics, Sunshine Hospitals Sunshine Hospitals, Secunderabad, Telangana, India
| | - Ajit Jungele
- Department of Orthopedics, Sunshine Hospitals Sunshine Hospitals, Secunderabad, Telangana, India
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Ganguly C, Prasad GJ, Mahule KN, Ghosh JK, Asari KVJ, Chandrasekharan KNP, Muralidhar S, Balan TS, Roy PR. Fabrication Experience of AI-233U and Al-Pu Plate Fuel for the Purnima III and Kamini Research Reactors. NUCL TECHNOL 2017. [DOI: 10.13182/nt91-a35534] [Citation(s) in RCA: 8] [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: 11/12/2022]
Affiliation(s)
- C. Ganguly
- Bhabha Atomic Research Centre, Bombay 400085, India
| | - G. J. Prasad
- Bhabha Atomic Research Centre, Bombay 400085, India
| | - K. N. Mahule
- Bhabha Atomic Research Centre, Bombay 400085, India
| | - J. K. Ghosh
- Bhabha Atomic Research Centre, Bombay 400085, India
| | | | | | | | - T. S. Balan
- Bhabha Atomic Research Centre, Bombay 400085, India
| | - P. R. Roy
- Bhabha Atomic Research Centre, Bombay 400085, India
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Kocabas F, Xie L, Xie J, Yu Z, DeBerardinis RJ, Kimura W, Thet S, Elshamy AF, Abouellail H, Muralidhar S, Liu X, Chen C, Sadek HA, Zhang CC, Zheng J. Hypoxic metabolism in human hematopoietic stem cells. Cell Biosci 2015. [PMID: 26221532 PMCID: PMC4517642 DOI: 10.1186/s13578-015-0020-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [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] [Indexed: 01/07/2023] Open
Abstract
Background Adult hematopoietic stem cells (HSCs) are maintained in a microenvironment, known as niche in the endosteal regions of the bone marrow. This stem cell niche with low oxygen tension requires HSCs to adopt a unique metabolic profile. We have recently demonstrated that mouse long-term hematopoietic stem cells (LT-HSCs) utilize glycolysis instead of mitochondrial oxidative phosphorylation as their main energy source. However, the metabolic phenotype of human hematopoietic progenitor and stem cells (HPSCs) remains unknown. Results We show that HPSCs have a similar metabolic phenotype, as shown by high rates of glycolysis, and low rates of oxygen consumption. Fractionation of human mobilized peripheral blood cells based on their metabolic footprint shows that cells with a low mitochondrial potential are highly enriched for HPSCs. Remarkably, low MP cells had much better repopulation ability as compared to high MP cells. Moreover, similar to their murine counterparts, we show that Hif-1α is upregulated in human HPSCs, where it is transcriptionally regulated by Meis1. Finally, we show that Meis1 and its cofactors Pbx1 and HoxA9 play an important role in transcriptional activation of Hif-1α in a cooperative manner. Conclusions These findings highlight the unique metabolic properties of human HPSCs and the transcriptional network that regulates their metabolic phenotype. Electronic supplementary material The online version of this article (doi:10.1186/s13578-015-0020-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Fatih Kocabas
- Department of Internal Medicine, Division of Cardiology, UT Southwestern Medical Center at Dallas, Dallas, TX 75390 USA.,Department of Genetics and Bioengineering, Faculty of Engineering, Yeditepe University, Istanbul, 34755 Turkey
| | - Li Xie
- Hongqiao International Institute of Medicine, Shanghai Tongren Hospital / Faculty of Basic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China.,Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Chongqing South Road 280, Shanghai, 200025 China
| | - Jingjing Xie
- Bingzhou Medical University, Taishan Scholar Program, Yantai, 264003 China
| | - Zhuo Yu
- Hongqiao International Institute of Medicine, Shanghai Tongren Hospital / Faculty of Basic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China.,Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Chongqing South Road 280, Shanghai, 200025 China
| | - Ralph J DeBerardinis
- Departments of Pediatrics and Genetics, UT Southwestern Medical Center at Dallas, Dallas, TX 75390 USA
| | - Wataru Kimura
- Department of Internal Medicine, Division of Cardiology, UT Southwestern Medical Center at Dallas, Dallas, TX 75390 USA
| | - SuWannee Thet
- Department of Internal Medicine, Division of Cardiology, UT Southwestern Medical Center at Dallas, Dallas, TX 75390 USA
| | - Ahmed F Elshamy
- Department of Clinical Pathology, El Galaa Hospital, Cairo, Egypt
| | | | - Shalini Muralidhar
- Department of Internal Medicine, Division of Cardiology, UT Southwestern Medical Center at Dallas, Dallas, TX 75390 USA
| | - Xiaoye Liu
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Chongqing South Road 280, Shanghai, 200025 China
| | - Chiqi Chen
- Hongqiao International Institute of Medicine, Shanghai Tongren Hospital / Faculty of Basic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China
| | - Hesham A Sadek
- Department of Internal Medicine, Division of Cardiology, UT Southwestern Medical Center at Dallas, Dallas, TX 75390 USA
| | - Cheng Cheng Zhang
- Departments of Physiology and Developmental Biology, UT Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390 USA
| | - Junke Zheng
- Hongqiao International Institute of Medicine, Shanghai Tongren Hospital / Faculty of Basic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China.,Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Chongqing South Road 280, Shanghai, 200025 China
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Abstract
SIGNIFICANCE Utilizing oxygen (O2) through mitochondrial oxidative phosphorylation enables organisms to generate adenosine triphosphate (ATP) with a higher efficiency than glycolysis, but it results in increased reactive oxygen species production from mitochondria, which can result in stem cell dysfunction and senescence. RECENT ADVANCES In the postnatal organism, the hematopoietic system represents a classic example of the role of stem cells in cellular turnover and regeneration. However, in other organs such as the heart, both the degree and source of cellular turnover have been heavily contested. CRITICAL ISSUES Although recent evidence suggests that the major source of the limited cardiomyocyte turnover in the adult heart is cardiomyocyte proliferation, the identity and potential role of undifferentiated cardiac progenitor cells remain controversial. Several types of cardiac progenitor cells have been identified, and several studies have identified an important role of redox and metabolic regulation in survival and differentiation of cardiac progenitor cells. Perhaps a simple way to approach these controversies is to focus on the multipotentiality characteristics of a certain progenitor population, and not necessarily its ability to give rise to all cell types within the heart. In addition, it is important to note that cycling cells in the heart may express markers of differentiation or may be truly undifferentiated, and for the purpose of this review, we will refer to these cycling cells as progenitors. FUTURE DIRECTIONS We propose that hypoxia, redox signaling, and metabolic phenotypes are major regulators of cardiac renewal, and may prove to be important therapeutic targets for heart regeneration.
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Affiliation(s)
- Wataru Kimura
- 1 Division of Cardiology, Department of Internal Medicine, UT Southwestern Medical Center , Dallas, Texas
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Gupta K, Bala M, Deb M, Muralidhar S, Sharma DK. Prevalence of intestinal parasitic infections in HIV-infected individuals and their relationship with immune status. Indian J Med Microbiol 2013; 31:161-5. [PMID: 23867673 DOI: 10.4103/0255-0857.115247] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND AND OBJECTIVES Intestinal parasitic infection is a common entity in patients infected with human immunodeficiency virus (HIV). These infections may lead to fatal complications in the immuno suppressed individuals. The aim of the present study was to determine the prevalence of intestinal parasitic infections in HIV sero-positive patients and their relationship with the immune status of individuals. MATERIALS AND METHODS Fecal samples from 100 HIV sero-positive and an equal number of HIV sero-negative individuals were collected and examined for enteric parasites by direct microscopy. CD4 counts were carried out in only HIV sero-positive patients. Prevalence of intestinal parasites in patients with CD4 count<200 cells/μl, 200-499 cells/μl, and ≥500 cells/μl in HIV-infected patients were compared. RESULTS Enteric parasites were detected in 59.3% HIV-infected patients with CD4 count<200 cells/μl as compared with 23.5% in patients with CD4 count>200 cells/μl (P<0.01). Prevalence of coccidian parasites was significantly (P<0.01) higher (14%) in HIV sero-positive subjects compared with HIV sero-negative subjects (2%). Isospora belli (25%) was the most common parasite with CD4 count<200 cells/μl, followed by Cryptosporidium parvum (12.5%). Prevalence of intestinal parasitic infections was significantly higher in patients with diarrhea, 73.6% than without diarrhea, 25.9%, (P<0.05). The mean CD4 count of HIV sero-positive patients presenting with diarrhea was significantly (P<0.01) lower (181.26±135.14) than without diarrhea (352.02±204.03). CONCLUSION This study emphasizes the need for routine screening of parasites especially in patients with lower CD4 count so as to decrease the morbidity by ensuring the early treatment of the cases.
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Affiliation(s)
- K Gupta
- Department of Microbiology, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi-110 029, India
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Bala M, Singh V, Muralidhar S, Ramesh V. Assessment of reactivity of three treponemal tests in non-treponemal non-reactive cases from sexually transmitted diseases clinic, antenatal clinic, integrated counselling and testing centre, other different outdoor patient departments/indoor patients of a tertiary care centre and peripheral health clinic attendees. Indian J Med Microbiol 2013; 31:275-9. [DOI: 10.4103/0255-0857.115638] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Kocabas F, Mahmoud AI, Muralidhar S, Porrello E, Olson E, Sadek HA. Abstract 64: Meis1 Is a Key Regulator of Postnatal Cardiomyocyte Cell Cycle Arrest. Circ Res 2012. [DOI: 10.1161/res.111.suppl_1.a64] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Heart failure is a costly and deadly disease affecting over 5 million Americans. The inability of the adult mammalian heart to regenerate following injury lies at core of the pathophysiology of heart failure. We recently showed that the neonatal mammalian heart is capable of complete regeneration following resection of the entire ventricular apex. Moreover, our preliminary data indicate that the neonatal mouse heart is also capable of complete regeneration following ischemic myocardial infarction. In both these types of injury, the regenerative response is associated with robust proliferation of cardiomyocytes without significant hypertrophy or fibrosis. Genetic fate mapping studies demonstrated that the majority of newly formed cardiomyocytes originated from pre-existing cardiomyocytes. In an effort to determine the mechanism of cardiomyocytes cell cycle arrest after the first week of life, we performed a gene array after cardiac injury at multiple post-natal timepoints. This enabled us to identify Meis1 as a potential regulator of neonatal cardiomyocyte proliferation. Meis1, which belongs to the TALE family of homeodomain transcription factors, is required for normal hematopoiesis and cardiac development. While Meis1 has been extensively studied in the hematopoietic system, little is known about its role in the heart. Our results indicate that Meis1 expression and nuclear localization in the post-natal cardiomyocytes coincides with cell cycle arrest. To further explore this pattern, we generated a cardiomyocyte-specific Meis1 knockout mouse, and showed that loss of Meis1 results in robust cardiomyocyte proliferation in the adult heart. Moreover, we identified p16 and p21; two synergistic cyclin dependent kinase inhibitors that induce arrest at all three cell cycle checkpoints, as potential targets for transcriptional activation by Meis1. These results identify Meis1 as a key regulator of post-natal cardiomyocyte cell cycle arrest, and a potential therapeutic target for cardiac regeneration.
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Affiliation(s)
| | | | | | | | - Eric Olson
- UT Southwestern Med Cntr at Dallas, Dallas, TX
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Abstract
Curcumin, an important Asian spice, is part of many Indian food preparations. This work evaluates the antifungal activity of curcumin against 14 strains of Candida (10 clinical and 4 standard). Curcumin displayed antifungal properties against all tested Candida strains, with minimum inhibitory concentrations (MICs) varying from 250 to 2000 µg·mL⁻¹. The in vitro effect of curcumin on growth, sterol content, proteinase secretion, and H+ extrusion by plasma membrane ATPase was investigated for 2 standard strains Candida albicans ATCC 10261 and Candida glabrata ATCC 90030 and compared with the effect of fluconazole. At MIC, curcumin inhibited H+ extrusion in 2 species of Candida by 42% and 32% in the absence of glucose and by 28% and 18% in the presence of glucose. Respective inhibition of H+ extrusion caused by the MIC of fluconazole was 85% and 89% in the absence of glucose and 61% and 66% in its presence. Ergosterol content decreased by 70% and 53% for the 2 strains following exposure to curcumin at MIC; comparative values for fluconazole at MIC were 93% and 98%. Curcumin and fluconazole decreased proteinase secretion by 49% and 53%, respectively, in C. albicans and by 39% and 46%, respectively, in C. glabrata. In conclusion, curcumin is found to be active against all tested clinical and standard strains but is less effective than fluconazole. Antifungal activity of curcumin might be originating from alteration of membrane-associated properties of ATPase activity, ergosterol biosynthesis, and proteinase secretion.
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Affiliation(s)
- K Neelofar
- Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India
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Gupta SM, Bala M, Muralidhar S, Ray K. Evaluation of test results of microbiology laboratories of North India for standard tests for syphilis under an external quality assurance scheme. Eur J Clin Microbiol Infect Dis 2008; 28:461-8. [PMID: 19015902 DOI: 10.1007/s10096-008-0651-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2008] [Accepted: 10/10/2008] [Indexed: 11/30/2022]
Abstract
Test results of syphilis serology are critical due to inter- and intralaboratory variability. The accuracy of results is crucial in the control of the disease. This study was aimed to compare results of laboratories and performance of methods for syphilis serology. Results of Veneral Disease Reference Laboratory (VDRL) or rapid plasma reagin (RPR) tests of 25 microbiology laboratories were compared in six proficiency testing sentinel surveys. The performance of laboratories was compared with the results of a hypothetical average laboratory. Of the 141 participants, 104 (73.8%) responded. The inter-laboratory variability was exhibited by 62.2% of samples tested by VDRL and 58.7% by RPR test. Intralaboratory variability was observed in 46.7% samples. There was an insignificant improvement in proficiency testing (PT) performance over the years with a significant improvement in 2007. The common errors involved departure from testing protocols. Syphilis serology proficiency testing is needed in India for reliability in test results.
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Affiliation(s)
- S M Gupta
- Training and Research Centre, Vardhnman Mahavir Medical College and Safdarjang Hospital, New Delhi, India
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16
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Liu L, Muralidhar S, Singh M, Sylvan C, Kalra IS, Quinn CT, Onyekwere OC, Pace BS. High-density SNP genotyping to define beta-globin locus haplotypes. Blood Cells Mol Dis 2008; 42:16-24. [PMID: 18829352 DOI: 10.1016/j.bcmd.2008.07.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2008] [Accepted: 07/24/2008] [Indexed: 10/21/2022]
Abstract
Five major beta-globin locus haplotypes have been established in individuals with sickle cell disease (SCD) from the Benin, Bantu, Senegal, Cameroon, and Arab-Indian populations. Historically, beta-haplotypes were established using restriction fragment length polymorphism (RFLP) analysis across the beta-locus, which consists of five functional beta-like globin genes located on chromosome 11. Previous attempts to correlate these haplotypes as robust predictors of clinical phenotypes observed in SCD have not been successful. We speculate that the coverage and distribution of the RFLP sites located proximal to or within the globin genes are not sufficiently dense to accurately reflect the complexity of this region. To test our hypothesis, we performed RFLP analysis and high-density single nucleotide polymorphism (SNP) genotyping across the beta-locus using DNA samples from healthy African Americans with either normal hemoglobin A (HbAA) or individuals with homozygous SS (HbSS) disease. Using the genotyping data from 88 SNPs and Haploview analysis, we generated a greater number of haplotypes than that observed with RFLP analysis alone. Furthermore, a unique pattern of long-range linkage disequilibrium between the locus control region and the beta-like globin genes was observed in the HbSS group. Interestingly, we observed multiple SNPs within the HindIII restriction site located in the Ggamma-globin intervening sequence II which produced the same RFLP pattern. These findings illustrated the inability of RFLP analysis to decipher the complexity of sequence variations that impacts genomic structure in this region. Our data suggest that high-density SNP mapping may be required to accurately define beta-haplotypes that correlate with the different clinical phenotypes observed in SCD.
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Affiliation(s)
- Li Liu
- Department of Molecular and Cell Biology, Sickle Cell Disease Research Center, University of Texas at Dallas, Richardson, TX 75083, USA
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Ray K, Bala M, Gupta SM, Khunger N, Puri P, Muralidhar S, Kumar J. Changing trends in sexually transmitted infections at a Regional STD Centre in north India. Indian J Med Res 2006; 124:559-68. [PMID: 17213525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023] Open
Abstract
BACKGROUND & OBJECTIVES Sexually transmitted infections (STIs) a major public health problem in India show various trends in different parts of the country. However, there are limited data on the changing profile of laboratory proven STIs in the same clinic over the years. The present study was thus aimed to determine the changing trends of the profile of STIs and HIV seropositivity in STD clinic attendees over a 15 yr period, and also to detect change, if any, in the antimicrobial resistance pattern of Neisseria gonorrhoeae. METHODS The STIs were diagnosed clinically and confirmed by standard laboratory techniques. Socio-demographic data were collected through pre-designed proformae. The STI profile and HIV seropositivity were compared between 1990-1993 (A), 1994-1997 (B), 1998-2001 (C) and 2002-2004 (D). Antimicrobial resistance pattern of N. gonorrhoeae was determined by standard techniques and compared between the last three periods. RESULTS Of the 78,617 STD attendees, 12,709 (16.2%) had STIs. During period A, genital discharges and during B, C and D, genital ulcerative diseases were predominant. Syphilis was the commonest STI. There was significant rise in the cases of syphilis, herpes progenitalis and genital warts and reduction in that of chancroid, lymphogranulomavenereum (LGV), donovanosis, candidiasis, trichomoniasis and bacterial vaginosis cases. The number of cases with primary syphilis diminished significantly (P<0.001), with a concomitant rise in secondary and early latent syphilis. A rising trend was observed in the HIV seropositivity during the different periods. The association of HIV seropositivity was consistently more in patients presenting with genital ulcers specially syphilis, and rose significantly from A (0.6%) to C (8.8%), but became stationary during D. A drastic change in the antimicrobial resistance of N. gonorrhoeae from B to C and C to D and the emergence of less sensitive isolates to ceftriaxone during the later part of the study were observed. INTERPRETATION & CONCLUSION Our study showed a definite changing trend in the profile of STIs in the clinic attendees of a major STD centre during a 15 yr period. However, the significant rise in the cases of viral STIs and syphilis contrasted with reduction in the rest.
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Affiliation(s)
- Krishna Ray
- Regional STD Teaching, Training & Research Centre, Vardhman Mahavir Medical College & Safdarjang Hospital, New Delhi, India
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Abstract
During the 1990s, no studies of various clinical presentations of syphilis have been published in the indexed literature. However, a change in the clinical profile of secondary syphilis was expected during the last decade with the rapid spread of the HIV epidemic. The objective was to study the mucocutaneous manifestations of secondary syphilis in patients attending the STD clinic at the Postgraduate Institute of Medical Education & Research Chandigarh, India, during the last decade and to compare them with other similar studies published during the 1980s. All patients who were diagnosed with secondary syphilis in our STD clinic from 1990 to 1999 were examined and investigated. Serological response was measured at 3, 6, 9, 12, and 24 months post-treatment or until serological negativity was reached. Fifty-three patients (males = 34, female = 19) during this period were found to have secondary syphilis. The most common symptoms were as follows-skin rash 38 (71.7%), lymphadenopathy 26 (49%), persistent chancre 4 (7.5%), nodular syphilides 2 (3.8%), lues maligna 2 (3.8%), patches in the oral mucosa 6 (11.3%), condylomata lata 14 (26.4%), split papules 2 (3.8%). Five patients had a thin and conspicuous genital scar of the healed primary chancre. Three patients were HIV seropositive (1 patient each with lues maligna, lichenoid, and nodular syphilides). With the spread of the HIV epidemic, atypical muco-cutaneous manifestations of secondary syphilis may be seen more frequently than before and may pose problems in diagnosis. In the present study, six patients had atypical manifestations, and three of them were HIV seropositive.
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Affiliation(s)
- B Kumar
- Department of Dermatology Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Gupta D, Saiprakash BV, Aggarwal AN, Muralidhar S, Kumar B, Jindal SK. Value of different cut-off points of tuberculin skin test to diagnose tuberculosis among patients with respiratory symptoms in a chest clinic. J Assoc Physicians India 2001; 49:332-5. [PMID: 11291972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To assess the utility of various cut-off points of tuberculin skin test in making a diagnosis of tuberculosis in patients with respiratory symptoms. METHODS Tuberculin skin test was conducted on consecutive new patients attending chest clinic for various respiratory symptoms. All subjects were then investigated to establish diagnosis, and categorized into tuberculous and nontuberculous groups. Receiver operating characteristic (ROC) curve was plotted to evaluate discrimination by tuberculin skin test. Sensitivity, specificity and predictive value were also calculated at various cut-off points. RESULTS Of 250 patients, 59 (23.6%) had tuberculosis on clinical and microbiological criteria (other than the tuberculin test). Sensitivity and specificity of tuberculin test at readings greater than 5, 10 and 15 mm were 0.8136 and 0.7068, 0.6271 and 0.8901, and 0.2034 and 0.9738 respectively. Area under ROC curve for this test was 0.80. CONCLUSION A cut-off point of 10 mm is likely to be useful in supporting a diagnosis of tuberculosis in patients with strong clinical suspicion of tuberculosis, in other patients, 15 mm cut-off may be more suitable.
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Affiliation(s)
- D Gupta
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Abstract
AIMS We undertook this study to analyse the pattern of childhood cutaneous tuberculosis prevailing in northern India over the past 25 years and to highlight differences from and similarities to adult tuberculosis. MATERIALS AND METHODS Clinical records of children with cutaneous tuberculosis who attended the Nehru Hospital attached to the Postgraduate Institute of Medical Education and Research, Chandigarh, India, between January 1975 to December 1999 were analysed. RESULTS Four hundred and two patients with cutaneous tuberculosis were examined during the 25-year period of observation. These patients formed 0.1% of the total dermatology outpatients. Seventy-five (18.7%) of these 402 cases were children (</= 16 years). There were 32 (42.7%) boys and 43 (57.3%) girls with a boy : girl ratio of 0.74 : 1. The majority of the children, 41 (54.7%) were in the 10-14 years age group. There was no significant boy or girl preponderance in any group other than in scrofuloderma (SFD), where girls significantly outnumbered boys at all ages. Of the various patterns of cutaneous tuberculosis seen, 40 (53.3%) had SFD, 30 (40.0%) had lupus vulgaris (LV), 3 (4.0%) had tuberculosis verrucosa cutis (TVC), 1 (1.3%) child each had tuberculids and tubercular gumma. No child had a tubercular chancre or acute miliary cutaneous tuberculosis. The neck was the commonest site afflicted with SFD and the face was the commonest site affected with LV. No child had generalized lymphadenopathy. Eighteen (60.0%) of the 30 children with LV had regional lymphadenopathy of which 15 (83.3%) had localized disease and 3 (16.7%) had disseminated disease. Of the 16 children with systemic organ involvement, 12 (75.0%) had regional lymphadenopathy. Of the 62 children in whom the data regarding vaccination status was available, 31 (50.0%) had been vaccinated and 31 (50.0%) had not. Among the vaccinated group no child had disseminated disease. Three (9.7%) children in the nonvaccinated group had disseminated disease. Information regarding Mantoux reactivity was available in 71 (94.7%) children, 61 (86.0%) with localized disease and 10 (14.1%) with disseminated disease. Of the 61 children with localized disease, 56 (91.8%) were Mantoux positive and of the 10 children with disseminated disease, only 5 (50.0%) were Mantoux positive (> 10 mm). Histopathologic reports were available for evaluation in all 75 children. Out of 30 cases of LV, 24 (80%) showed classical tuberculous histology. In contrast, out of 40 cases with SFD, only 19 (47.5%) showed classical histology. Classical tuberculous histology was noted in all 3 (100%) cases of TVC and 1 (100%) case each with tuberculids and gumma. Tubercle bacilli could be demonstrated in 4/30 (13.3%) cases with LV and 9/40 (22.5%) cases with SFD. Systemic involvement was seen in 16 (21.3%) children, of whom 3 (18.8%) had LV and 13 (81.3%) SFD. The lungs were the most common organs involved in 8 (50.0%) children followed by bone(s) in 4 (25.0%), abdomen in 2 (12.5%), and both lung and bone in 1 (6.3%) child. In contrast to adults, girls outnumbered boys in the childhood series; SFD was a common form of presentation in contrast to LV and TVC, tuberculous gumma and tuberculids were noted less often. In both children and adults, Mantoux reactivity did not correlate with the extent of the disease; patients with disseminated disease were found to be less often vaccinated with BCG and regional lymphadenopathy was noted more often in patients with disseminated disease. CONCLUSIONS In the whole spectrum of cutaneous tuberculosis, there is a proportion of patients with dissemination (systemic involvement) who are of great epidemiological significance as they require a change in the standard therapeutic regimens recommended for cutaneous tuberculosis.
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Affiliation(s)
- B Kumar
- Department of Dermatology, Venereology & Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
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Muralidhar S, Veytsmann G, Chandran B, Ablashi D, Doniger J, Rosenthal LJ. Characterization of the human herpesvirus 8 (Kaposi's sarcoma-associated herpesvirus) oncogene, kaposin (ORF K12). J Clin Virol 2000; 16:203-13. [PMID: 10738139 DOI: 10.1016/s1386-6532(99)00081-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Human herpesvirus 8 (HHV-8) has been implicated in the etiology of Kaposi's sarcoma (KS), a highly angiogenic tumor of complex histology, and two lymphoproliferative diseases, primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). A number of HHV-8 encoded genes have been proposed to be involved in the pathogenesis of KS and PEL and a few have been shown to be oncogenic in heterologous systems (Reyes GR, LaFemina R, Hayward SD, Hayward GS. Morphological transformation by DNA fragments of human herpesviruses: evidence for two distinct transforming regions in herpes simplex virus types 1 and 2 and lack of correlation with biochemical transfer of the thymidine kinase gene. Cold Spring Harbor Symp Quant Biol 1980;44:629-641; Moore PS, Boshoff C, Weiss RA, Chang Y. Molecular mimicry of human cytokine and cytokine response pathway genes by KSHV. Science 1996;274:1739-1744; Cheng EH, Nicholas J, Bellows DS, Hayward GS, Guo HG, Reitz MS, Hardwick JM. A Bcl-2 homolog encoded by Kaposi sarcoma-associated virus, human herpesvirus 8, inhibits apoptosis but does not heterodimerize with Bax or Bak. Proc Natl Acad Sci USA 1997;94:690-694; Li M, Lee H, Yoon DW, Albrecht JC, Fleckenstein B, Neipel F, Jung JU. Kaposi's sarcoma-associated herpesvirus encodes a functional cyclin. J Virol 1997;71:1984-1991; Neipel F, Albrecht J-C, Fleckenstein B. Cell-homologous genes In the Kaposi's sarcoma-associated rhadinovirus human herpesvirus 8: determinants of its pathogenicity? J Virol 1997;71:4187-4192; Nicholas J, Ruvolo VR, Burns WH, Sandford G, Wan X, Ciufo D, Hendrickson SB, Guo HG, Hayward GS, Reitz MS. Kaposi's sarcoma-associated human herpesvirus-8 encodes homologues of macrophage inflammatory protein-1 and interleukin-6. Nat Med 1997;3:287-292; Nicholas J, Zong J, Alcendor DJ, Ciufu DM, Poole LJ, Sarisky RT, Chiuo C, Zhang X, Wan X, Guo H, Reitz MS, Hayward GS. Novel organizational features, captured cellular genes, and strain variability within the genome of KSHV/HHV-8. JNCI Monographs 1998;23:79-88; Muralidhar S, Pumfery AM, Hassani M, Sadaie MR, Azumi N, Kishishita M, Brady JN, Doniger J, Medveczky P, Rosenthal LJ. Identification of kaposin (ORF K12) as a human herpesvirus 8 (Kaposi's sarcoma associated herpesvirus) transforming gene. J Virol 1998;72:4980-4988). The kaposin gene (ORF K12) encoded by the abundant latency-associated HHV-8 transcript, T0.7, has been previously shown to induce tumorigenic transformation of Rat-3 cells (Muralidhar S, Pumfery AM, Hassani M, Sadaie MR, Azumi N, Kishishita M, Brady JN, Doniger J, Medveczky P, Rosenthal LJ. Identification of kaposin (ORF K12) as a human herpesvirus 8 (Kaposi's sarcoma associated herpesvirus) transforming gene. J Virol 1998;72:4980-4988). The current study is a further characterization of kaposin protein. OBJECTIVES Characterization of kaposin expression in transformed and tumor-derived Rat-3 cells as well as PEL cell lines, BCBL-1, BC-3 and KS-1 and analysis of mechanism(s) of transformation. DESIGN The presence of kaposin DNA in transformed cells was determined by fluorescent in situ hybridization (FISH). Expression of kaposin protein was analyzed by Western blot analysis and indirect immunofluorescence assay (IFA). (ABSTRACT TRUNCATED)
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MESH Headings
- Animals
- Blotting, Western
- Cell Line, Transformed
- DNA, Viral/analysis
- Fluorescent Antibody Technique, Indirect
- Golgi Apparatus/metabolism
- Herpesvirus 8, Human/genetics
- Herpesvirus 8, Human/metabolism
- Humans
- In Situ Hybridization, Fluorescence
- Oncogene Proteins, Viral/genetics
- Oncogene Proteins, Viral/metabolism
- Protein Serine-Threonine Kinases/metabolism
- Rats
- Sarcoma, Kaposi/virology
- Tumor Cells, Cultured
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Affiliation(s)
- S Muralidhar
- Department of Microbiology, Georgetown University Medical Center, 3900 Reservoir Road N.W., Washington, DC, USA
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Muralidhar S, Srivastava L, Aggarwal P, Jain N, Sharma DK. Fasciolopsiasis--a persisting problem in eastern U.P.--a case report. INDIAN J PATHOL MICR 2000; 43:69-71. [PMID: 12583424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
Fasciolopsiasis, or infection by the intestinal fluke, Fascilopsis buski, is endemic in the eastern states of our country. While it is by no means a rarity, especially in the rural set up, awareness regarding this common parasitic infestation is still a much-needed entity. The importance of a strong degree of suspicion and early diagnosis cannot be over emphasised, if a successful campaign is to be launched in its control. With this as our central theme, we proceed to report a case of and unsually heavy Fasciolopsis buski infection in our hospital, which had failed to be diagnosed in a semi urban setup in UP.
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Affiliation(s)
- S Muralidhar
- Department of Microbiology, Safdarjang Hospital, New Delhi
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Muralidhar S, Handa S, Sharma VK, Kumar B, Mitali G. Scar sarcoidosis - sparing post surgical scar. Indian J Dermatol Venereol Leprol 1999; 65:279-280. [PMID: 20921686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Affiliation(s)
- S Muralidhar
- From the Departments of Dermatology, Venereology and Leprology, and Pathology, Postgraduate Institute of Medical Education and Research, Chandigarh - 160 012, India,
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Abstract
This review is an update on the transforming genes of human cytomegalovirus (HCMV) and human herpesvirus 6 (HHV-6). Both viruses have been implicated in the etiology of several human cancers. In particular, HCMV has been associated with cervical carcinoma and adenocarcinomas of the prostate and colon. In vitro transformation studies have established three HCMV morphologic transforming regions (mtr), i.e., mtrI, mtrII, and mtrIII. Of these, only mtrII (UL111A) is retained and expressed in both transformed and tumor-derived cells. The transforming and tumorigenic activities of the mtrII oncogene were localized to an open reading frame (ORF) encoding a 79-amino-acid (aa) protein. Furthermore, mtrII protein bound to the tumor suppressor protein p53 and inhibited its ability to transactivate a p53-responsive promoter. In additional studies, the HCMV immediate-early protein IE86 (IE2; UL122) was found to interact with cell cycle-regulatory proteins such as p53 and Rb. However, IE86 exhibited transforming activity in vitro only in cooperation with adenovirus E1A. HHV-6 is a T-cell-tropic virus associated with AIDS-related and other lymphoid malignancies. In vitro studies identified three transforming fragments, i.e., SalI-L, ZVB70, and ZVH14. Of these, only SalI-L (DR7) was retained in transformed and tumor-derived cells. The transforming and tumorigenic activities of SalI-L have been localized to a 357-aa ORF-1 protein. The ORF-1 protein was expressed in transformed cells and, like HCMV mtrII, bound to p53 and inhibited its ability to transactivate a p53-responsive promoter. HHV-6 has also been proposed to be a cofactor in AIDS because both HHV-6 and human immunodeficiency virus type 1 (HIV-1) have been demonstrated to coinfect human CD4(+) T cells, causing accelerated cytopathic effects. Interestingly, like the transforming proteins of DNA tumor viruses such as simian virus 40 and adenovirus, ORF-1 was also a transactivator and specifically up-regulated the HIV-1 long terminal repeat when cotransfected into CD4(+) T cells. Finally, based on the interactions of HCMV and HHV-6 transforming proteins with tumor suppressor proteins, a scheme is proposed for their role in oncogenesis.
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Affiliation(s)
- J Doniger
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, D.C. 20007, USA
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Kumar B, Muralidhar S. Cutaneous tuberculosis: a twenty-year prospective study. Int J Tuberc Lung Dis 1999; 3:494-500. [PMID: 10383062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
SETTING A tertiary care hospital in northern India. OBJECTIVE To study the patterns of clinical presentation of cutaneous tuberculosis, to correlate them with Mantoux reactivity and BCG vaccination status, and to suggest a clinical classification based on these factors. DESIGN Analysis of the records of patients with cutaneous tuberculosis who attended the hospital between 1975 and 1995. RESULTS A total of 0.1% of dermatology patients had cutaneous tuberculosis. Lupus vulgaris was the commonest form, seen in 154 (55%) of these patients, followed by scrofuloderma in 75 (26.8%), tuberculosis verrucosa cutis in 17 (6%), tuberculous gumma(s) in 15 (5.4%) and tuberculids in 19 (6.8%). No correlation was found between Mantoux reactivity and the extent of disease (localised disease 63.6%, disseminated disease 67.9%). The presence of regional lymphadenopathy was an indication of dissemination of the disease (localised disease 34.7%, disseminated disease 71.7%). Dissemination of the disease was observed in the whole of the spectrum of cutaneous tuberculosis (22.1%), but was seen more often in the presence of gumma and scrofuloderma. There were more unvaccinated individuals in the group with disseminated disease (80.3%) than in those with localised disease (65.5%). CONCLUSIONS Lupus vulgaris was the most common clinical presentation, followed by scrofuloderma, tuberculids, tuberculosis verrucosa cutis and tuberculous gumma. Some patients presented more than one clinical form of the disease. Classification of cutaneous tuberculosis needs to be modified to include smear-positive and smear-negative scrofuloderma apart from the inclusion of disseminated disease. The presence of regional lymphadenopathy serves as a clinical indicator of disseminated disease. Patients with disseminated disease were less likely to have been BCG-vaccinated than those with localised disease.
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Affiliation(s)
- B Kumar
- Department of Dermatology, Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
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Abstract
Syphilis is a disorder that may mimic many other diseases. Its incidence has risen and fallen over the centuries. A particularly malignant and virulent form, lues maligna, has recently been more frequently observed in the HIV-infected population. Raising the awareness of the occurrence of and the clinical and laboratory criteria of syphilis in general and lues maligna in particular in the HIV-infected population is becoming more urgent. Early treatment can result in a good outcome and stem the spread of the disease; as with other forms of syphilis, penicillin is the drug of choice.
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Affiliation(s)
- B Kumar
- Department of Dermatology, Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Abstract
Sixteen patients up to 18 years of age with widespread alopecia areata (AA) were recruited for the study. They included 10 patients with extensive AA (> or = 40% loss of scalp hair and or more than 10 patches scattered over the scalp and body) and 3 each with alopecia totalis and circumscribed alopecia areata. Patients were divided into two groups. In group A, aged 12 to 18 years, patients received 300 mg of prednisolone in a monthly oral pulse; in group B, aged 3 to 11 years, patients received betamethasone sodium phosphate as soluble tablets or syrup equivalent to prednisolone 5 mg/kg body weight every month. The pulsed doses of corticosteroid were continued for a minimum of three doses or until cosmetically acceptable hair growth was obtained. All patients but one 5-year-old girl received a minimum of three doses. Excellent hair growth was obtained in 9 (60%) of 15 patients evaluated at 6 months. Four patients out of 13 (>12 month follow-up), including two each in group A and B, developed a localized relapse during mean follow-up of 16.4 and 33.7 months in group A and B, respectively. Side effects of pulsed corticosteroid were minimal and were recorded in two patients (transient giddiness and headache, epigastric burning in one each). We recommend pulsed doses of prednisolone as one of the modalities in the treatment of widespread AA in young patients, including children.
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Affiliation(s)
- V K Sharma
- Department of Dermatology, Venerology, and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Kumar B, Muralidhar S. Mupirocin in folliculitis cruris pustulosa et atrophicans. Indian J Dermatol Venereol Leprol 1998; 64:207-208. [PMID: 20921769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Affiliation(s)
- B Kumar
- Department of Dermatology, Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh- 160012, India,
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Muralidhar S, Pumfery AM, Hassani M, Sadaie MR, Kishishita M, Brady JN, Doniger J, Medveczky P, Rosenthal LJ. Identification of kaposin (open reading frame K12) as a human herpesvirus 8 (Kaposi's sarcoma-associated herpesvirus) transforming gene. J Virol 1998; 72:4980-8. [PMID: 9573267 PMCID: PMC110060 DOI: 10.1128/jvi.72.6.4980-4988.1998] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The recently identified human herpesvirus 8 (HHV-8, or Kaposi's sarcoma-associated herpesvirus) has been implicated in the etiology of both Kaposi's sarcoma (KS) and primary effusion (body cavity-based) lymphoma (PEL) (Y. Chang et al., Science 266:1865-1869, 1994; P. S. Moore et al., J. Virol. 70:549-558, 1996). An important feature of the association of HHV-8 with these malignancies is the expression of an abundant, latency-associated 0.7-kb transcript, T0. 7 (W. Zhong et al., Proc. Natl. Acad. Sci. USA 93:6641-6646, 1996). T0.7 is found in all stages in nearly all KS tumors of different epidemiologic origin, including AIDS-associated, African endemic, and classical KS (K. A. Staskus et al., J. Virol. 71:715-719, 1997), as well as in a body cavity-based lymphoma-derived cell line, BCBL-1, that is latently infected with HHV-8 (R. Renne et al., Nat. Med. 2:342-346, 1996). T0.7 encodes a unique HHV-8 open reading frame, K12, also known as kaposin. In this study, we report that the kaposin gene induced tumorigenic transformation. Constructs with kaposin expressed either from its endogenous promoter or from a heterologous promoter induced focal transformation upon transfection into Rat-3 cells. All transformed Rat-3 cell lines containing kaposin sequences produced high-grade, highly vascular, undifferentiated sarcomas upon subcutaneous injection of athymic nu/nu mice. Tumor-derived cell lines expressed kaposin mRNA, suggesting a role in the maintenance of the transformed phenotype. Furthermore, kaposin protein was detected in transformed and tumor-derived cells by immunofluorescence and localized to the cytoplasm. More importantly, expression of kaposin protein was also detected in the PEL cell lines BCBL-1 and KS-1. These findings demonstrate the oncogenic potential of kaposin and suggest its possible role in the development of KS and other HHV-8-associated malignancies.
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Affiliation(s)
- S Muralidhar
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, D.C. 20007, USA
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Affiliation(s)
- B Kumar
- Department of Dermatology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Abstract
Three hundred and fifty six patients (234 males, 122 females) with alopecia areata were classified according to Ikeda's classification. The common type of alopecia areata was most frequently seen in 239 (67.13%) patients, followed by atopic in 60 (16.85%), prehypertensive in 48 (13.4%), and autoimmune/endocrine in 9 (2.52%) patients. Severe alopecia did not occur with a higher frequency in atopic or endocrine/autoimmune alopecia areata than in the common type (p > 0.05). Prehypertensive alopecia areata had the lowest frequency of severe alopecia in the present study. The odds for developing severe alopecia were highest (2.6) when onset was before 16 years of age, followed by female sex (2.12), atopy (0.86), autoimmune/endocrine (0.53), and prehypertensive (0.28) types. Alopecia areata should be broadly classified as childhood (< 16 years) and adult onset with subtypes of atopic, autoimmune/endocrine, and common type under both. The prehypertensive type should be combined with the common type of alopecia areata.
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Affiliation(s)
- V K Sharma
- Department of Dermatology, Venereology & Leprology Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Muralidhar S, Sulthana M. Nigrospora causing corneal ulcer--a case report. INDIAN J PATHOL MICR 1997; 40:549-51. [PMID: 9444870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
A patient from a rural background developed corneal ulceration following an insect hitting the eye. Corneal scrapings when processed for bacterial and fungal growth yielded Nigrospora, a contaminant fungus. This fungus has been quoted in literature as a common contaminant of no pathogenic significance. Herein, we describe its role as the causative agent of corneal ulcer, which has not been reported thus far.
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Affiliation(s)
- S Muralidhar
- Department of Microbiology, Safdarjung Hospital, New Delhi
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Abstract
BACKGROUND The etiology of Peyonie's disease remains a mystery. An attempt is made to resolve this. MATERIALS AND METHODS A total of 25 patients with Peyronie's disease were examined and investigated for the presence of various implicated etiologic factors. RESULTS Of the 25 patients examined, two presented with ischemic heart disease, 10 with hypertension, 10 with asymptomatic hyperuricemia, 18 with hypercholesterolemia, two with fibrosing disorders, two with autoimmune disorders, and three with diabetes mellitus. None had any sexually transmitted disease. Seven of the 10 hypertensive patients had received beta-blockers. On comparing the prevalence of these factors between patients and the general population, a significant association was found between hypertension, hypercholesterolemia, hyperuricemia, and Peyronie's disease. CONCLUSIONS Known factors, such as hypertension and hypercholesterolemia, lead to weakening of the vasculature and its rupture during coitus. This leads to the formation of a hematoma and its subsequent organization in predisposed individuals to fibrous plaques. The identification and treatment of these factors might prevent, secondarily, the development of Peyronie's disease.
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Affiliation(s)
- S Muralidhar
- Department of Dermatology, Institute of Medical Education and Research, Chandigarh, India
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Kumar B, Muralidhar S. Genital ulcer and viral warts. Indian J Dermatol Venereol Leprol 1997; 63:213-214. [PMID: 20944332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Affiliation(s)
- B Kumar
- Department of Dermatology, Venereology and Leprology, PG I MER Chandigarh - 160 012, India
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Kashanchi F, Araujo J, Doniger J, Muralidhar S, Hoch R, Khleif S, Mendelson E, Thompson J, Azumi N, Brady JN, Luppi M, Torelli G, Rosenthal LJ. Human herpesvirus 6 (HHV-6) ORF-1 transactivating gene exhibits malignant transforming activity and its protein binds to p53. Oncogene 1997; 14:359-67. [PMID: 9018122 DOI: 10.1038/sj.onc.1200840] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The 357 amino acid open reading frame 1 (ORF-1), also designated DR7, within the SalI-L fragment of human herpesvirus 6 (HHV-6) exhibited transactivation of the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) promoter and increased HIV-1 replication (Kashanchi et al., Virology, 201, 95-106, 1994). In the current study, the SalI-L transforming region was localized to the SalI-L-SH subfragment. Several ORFs identified in SalI-L-SH by sequence analysis were cloned into a selectable mammalian expression vector, pBK-CMV. Only pBK/ORF1 transformed NIH3T3 cells. Furthermore, cells expressing ORF-1 protein produced fibrosarcomas when injected into nude mice, whereas control cells, expressing either no ORF-1 protein or C-terminal truncated (after residue 172) ORF-1 protein, were not tumorigenic. Western blot analysis of proteins extracted from the tumors revealed ORF-1 protein. Additional studies indicated that ORF-1 was expressed in HHV-6-infected human T-cells by 18 h. Co-immunoprecipitation experiments showed that ORF-1 protein bound to tumor suppressor protein p53, and the ORF-1 binding domain on p53 was located between residues 28 and 187 of p53, overlapping with the specific DNA binding domain. Functional studies showed that p53-activated transcription was inhibited in ORF-1, but not in truncated ORF-1, expressing cells. Importantly, the truncated ORF-1 mutant also failed to cause transformation. Analysis of several human tumors by PCR revealed ORF-1 DNA sequences in some angioimmunoblastic lymphadenopathies, Hodgkin's and non-Hodgkin's lymphomas and glioblastomas. The detection of ORF-1 sequences in human tumors, while not proof per se, is a prerequisite for establishing its role in tumor development. Taken together, the results demonstrate that ORF-1 is an HHV-6 oncogene that binds to and affects p53. The identification of both transforming and transactivating activities within ORF-1 is a characteristic of other viral oncogenes and is the first reported for HHV-6.
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Affiliation(s)
- F Kashanchi
- Laboratory of Molecular Virology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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Muralidhar S, Doniger J, Mendelson E, Araujo JC, Kashanchi F, Azumi N, Brady JN, Rosenthal LJ. Human cytomegalovirus mtrII oncoprotein binds to p53 and down-regulates p53-activated transcription. J Virol 1996; 70:8691-700. [PMID: 8970996 PMCID: PMC190964 DOI: 10.1128/jvi.70.12.8691-8700.1996] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The 79-amino-acid (79-aa) open reading frame (UL111a) gene within morphological transforming region II (mtrII) of human cytomegalovirus strain Towne has been shown to transform rodent cells in vitro (J. Thompson, J. Doniger, and L. J. Rosenthal, Arch. Virol. 136:161-172, 1994). Moreover, a translation termination linker (TTL) mutant of mtrII that coded for the first 49 aa of mtrII oncoprotein (designated TTL49) was sufficient for malignant transformation, whereas a TTL mutant that coded for the first 24 aa (designated TTL24) was not. The current study demonstrates the binding of mtrII oncoprotein to the tumor suppressor protein p53 both in vivo using transiently transfected cells and in vitro using labeled proteins. Furthermore, the C-terminally truncated mtrII protein TTL49, but not truncated protein TTL24, bound to p53. The mtrII binding domain mapped to the N-terminal region of p53, residues 1 to 106, with a critical region from aa 27 to 44, whereas the p53 binding domain of mtrII protein was the first 49 aa. Furthermore, mtrII inhibited p53-activated transcription, indicating its ability to alter p53-directed cellular regulatory mechanisms. mtrII oncoprotein was detected both in stably transfected NIH 3T3 cell lines and human cytomegalovirus-infected HEL 299 cells (as early as 12 h after infection) in the perinuclear region and in the nucleus. mtrII-transformed cell lines, at both early and late passage, exhibited high levels of p53 with a 15-fold-extended half-life. However, p53-activated transcription was suppressed in these cells in spite of the increased p53 levels. Finally, the results with wild-type mtrII and its TTL mutants with respect to p53 binding, p53-activated transcription, and transforming ability suggest that the mechanism of mtrII transformation is linked to both p53 binding and disruption of p53 cell regulation.
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Affiliation(s)
- S Muralidhar
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, D.C. 20007, USA
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Abstract
A study was undertaken to determine the usefulness of ultrasonography as an investigative tool, and its role in deciding the management of Peyronie's disease. Fifteen patients with Peyronie's disease were studied by ultrasonography. The plaque could be demonstrated in all patients. The dimensions of the plaque varied from less than 1 cm to more than 7 cm in length and 2-4mm in thickness. The disease was active in 26% of the patients, as indicated by the presence of hypoechoic areas around a central region of hyperechoism. Ultrasonogram was more accurate than clinical assessment in delineating the extent of lesions. In one-third of the patients, sonography demonstrated the plaques to be more extensive than had been detected by clinical examination. Calcification and activity of disease (which are clearly defined by ultrasonogram) are determining factors in the management of Peyronie's disease. This information allows the surgeon to select the modality of treatment, the timing of surgery and extent of excision. Thus, ultrasonography plays a vital role in the preliminary investigation and management of Peyronie's disease.
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Affiliation(s)
- S Muralidhar
- Department of Dermatology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Muralidhar S, Sulthana CM. Rhodotorula causing chronic dacryocystitis: a case report. Indian J Ophthalmol 1995; 43:196-8. [PMID: 8655200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- S Muralidhar
- Department of Microbiology, Bangalore Medical College
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Muralidhar S, Becerra SP, Rose JA. Site-directed mutagenesis of adeno-associated virus type 2 structural protein initiation codons: effects on regulation of synthesis and biological activity. J Virol 1994; 68:170-6. [PMID: 8254726 PMCID: PMC236275 DOI: 10.1128/jvi.68.1.170-176.1994] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [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: 01/29/2023] Open
Abstract
It has been shown that two of the three adeno-associated virus type 2 capsid proteins, B and C, are synthesized from a single spliced transcript. Protein C arises from an AUG codon at nucleotide 2810, whereas protein B is initiated by a unique eucaryotic initiation codon (ACG) that lies 65 triplets upstream from the C origin. The third capsid component, protein A, is synthesized from a second spliced transcript which uses an alternative 3' acceptor site. In this study we used oligonucleotide-directed mutagenesis to confirm the positions of the B initiation codon and the 3' acceptor sites for the alternatively spliced B/C and A protein messages. We also located definitively the protein A initiation codon, an AUG triplet mapping to nucleotide 2203. Mutagenesis of the B initiator permitted a direct test of the effect of increased B initiator strength on the translational efficiencies of the B and C proteins. It was found that conversion of the relatively inefficient protein B initiator (ACG) to an AUG enhanced the level of B synthesis while abolishing the synthesis of C from its downstream AUG initiator. Protein C synthesis thus depends on the strength of the B initiator, i.e., the relatively higher levels of C (approximately 20-fold greater than B) must result from frequent readthrough of the weak B initiator. Finally, we examined the abilities of mutants deficient in the synthesis of A, B, or C to produce infectious virions. We found that at least two of the structural proteins, B and C, are required for the production of infectious virions and that sequestration of single-stranded adeno-associated virus genomes from the pool of replicating DNA molecules does not occur in the absence of either of these proteins.
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Affiliation(s)
- S Muralidhar
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892
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