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Rubens FD, Rao RV, Chan V, Burwash IG. A Matched-Paired Comparative Analysis of the Hemodynamics of the Trifecta and Perimount Aortic Bioprostheses. J Heart Valve Dis 2015; 24:487-495. [PMID: 26897822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
BACKGROUND AND AIM OF THE STUDY Current cohort studies comparing the Trifecta valve to alternative pericardial bioprostheses are limited by selection bias. The study aim was to determine if hemodynamics are improved after the aortic valve implantation of a Trifecta valve as compared to a standard pericardial valve, when evaluated using strict paired matching for specific key relevant confounders. METHODS Valve hemodynamics were compared in patients undergoing implantation with a Trifecta or Perimount valve matched for left ventricular outflow tract (LVOT) diameter, gender, age, body size, and days since surgery, using a 1:1 matched-paired cohort analysis (n = 20 per group). RESULTS Patients receiving a Trifecta valve had a larger increase in indexed stroke volume (SVi) relative to baseline compared to the Perimount patients (p = 0.013), in whom SVi was decreased. The mean transvalvular pressure gradient was lower in Trifecta patients despite the larger SVi (p = 0.02). The effective orifice area (EOA) and indexed EOA (EOAi) were significantly larger in Trifecta patients compared to Perimount patients (2.04 +/- 0.46 versus 1.77 +/- 0.45 cm2, p = 0.049; 1.10 +/- 0.22 versus 0.95 +/- 0.06 cm2/m2, p = 0.027, respectively), and there was a greater increase in EOA and EOAi from baseline (p = 0.010 for both). Severe prosthesis-patient mismatch (PPM) (EOAi < or = 0.65 cm2/m2) was seen in two (10%) of the Perimount cases, but in none of the patients with the Trifecta valve (p = 0.072). CONCLUSION Trifecta valve implantation is associated with a significant improvement in EOA and a decreased incidence of PPM as compared to the Perimount valve. The superior hemodynamic outcomes observed support consideration of this valve for aortic valve replacement, particularly in patients with a small LVOT at risk for PPM.
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Abstract
Iniencephaly is a rare neural tube defect characterized by extreme retroflexion of the head with the absence of neck due to spinal deformities. The important features that help us to diagnose a case of iniencephaly are occipital bone deficit leading to enlarged foramen magnum, fusion of malformed cervical and thoracic vertebrae, and upward turned face with chin continuous with chest because of the absence of neck. The differential diagnoses include anencephaly with spinal retroflexion, Klippel–Fiel syndrome, nuchal tumors such as teratoma, goiter, and lymphangioma and Jarcho–Levin syndrome. Previously many case reports on radiological features of iniencephaly are published, but there are very few articles on necropsy findings and differential diagnosis. In the present case we have discussed in detail the necropsy findings of iniencephaly clausus with special reference to differential diagnosis.
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Affiliation(s)
- Padmaja R Kulkarni
- Department of Pathology, SDM College of Medical Sciences and Hospital, Dharwad, Karnataka, India
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Abstract
A 23 year old Asian female presented with swelling of right knee joint for 5 years with history of exacerbations and remissions of symptoms. She was initially diagnosed as a case of suprapatellar bursitis based on clinical and X-ray findings. Further evaluation with higher imaging modalities was pathognomonic of lipoma arborescens. Patient underwent synovectomy and the diagnosis was confirmed histologically. We describe a histologically proven case of lipoma arborescens to highlight the imaging findings on X-ray, Ultrasound and Magnetic resonance imaging with arthroscopic correlation. The unique feature of this case report is multimodality imaging correlation with arthroscopy and histopathology findings. We have highlighted the pathognomonic imaging findings of this rare but benign intra-articular lesion and also discussed the differential diagnosis in detail.
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Affiliation(s)
- Preetam B Patil
- Department of Radiodiagnosis and Imaging, SDM College of Medical Sciences and Hospital Dharwad, Karnataka State, India.
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Abstract
Primary synovial sarcoma (SS) of kidney is very rare and difficult to diagnose. Here, we present a case of a 21-year-old female clinically diagnosed as renal cell carcinoma. Right nephrectomy specimen showed a cystic tumor in the upper pole of kidney with areas of hemorrhage and solid growth. Histologically, it showed poorly differentiated cells with hemangiopericytoma-like vascular pattern. Morphologic and immunohistochemical features were compatible with the diagnosis of poorly differentiated SS of kidney. Primary renal SS is a recently described entity. To the best of our knowledge, approximately 34 cases have been reported till date and this is the eighth documented case of poorly differentiated variant. Most of the time, poorly differentiated SS of kidney exhibits hemangiopericytoma like histology. Reverse transcriptase-polymerase chain reaction analysis to demonstrate SYT-SSX fusion gene transcript helps to confirm the diagnosis.
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Affiliation(s)
- Vandana U Grampurohit
- Department of Pathology, S.D.M. College of Medical Sciences and Hospital, Dharwad, India
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5
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Gupta S, Castel H, Rao RV, Picard M, Lilly L, Faughnan ME, Pomier-Layrargues G. Improved survival after liver transplantation in patients with hepatopulmonary syndrome. Am J Transplant 2010; 10:354-63. [PMID: 19775311 DOI: 10.1111/j.1600-6143.2009.02822.x] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Hepatopulmonary syndrome (HPS) is present in 10-32% of chronic liver disease patients, carries a poor prognosis and is treatable by liver transplantation (LT). Previous reports have shown high LT mortality in HPS and severe HPS (arterial oxygen (PaO(2)) < or =50 mmHg). We reviewed outcomes in HPS patients who received LT between 2002 and 2008 at two transplant centers supported by a dedicated HPS clinic. We assessed mortality, complications and gas exchange in 21 HPS patients (mean age 51 years, MELD score 14), including 11/21 (52%) with severe HPS and 5/21 (24%) with living donor LT (median follow-up 20.2 months after LT). Overall mortality was 1/21 (5%); mortality in severe HPS was 1/11 (9%). Peritransplant hypoxemic respiratory failure occurred in 5/21 (24%), biliary complications in 8/21 (38%) and bleeding or vascular complications in 6/21 (29%). Oxygenation improved in all 19 patients in whom PaO(2) or SaO(2) were recorded. PaO(2) increased from 52.2 +/- 13.2 to 90.3 +/- 11.5 mmHg (room air) (p < 0.0001) (12 patients); a higher baseline macroaggregated albumin shunt fraction predicted a lower rate of postoperative improvement (p = 0.045) (7 patients). Liver transplant survival in HPS and severe HPS was higher than previously demonstrated. Severity of HPS should not be the basis for transplant refusal.
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Affiliation(s)
- S Gupta
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
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Krishnanand G, Kaur M, Rao RV, Monappa V. Oncocytic variant of mucoepidermoid carcinoma of submandibular gland: an unusual clinical and morphological entity. INDIAN J PATHOL MICR 2007; 50:538-40. [PMID: 17883126] [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: 05/17/2023] Open
Abstract
In this case report we describe a rare tumor--Oncocytic variant of Mucoepidermoid carcinoma of the submandibular salivary gland with a review of the literature. Oncocytic metaplasia in salivary glands is a benign change that is associated with increasing age and also seen in a few salivary gland neoplasms', which include oncocytoma, Warthin's tumor, and the rare, oncocytic carcinoma. Oncocytic differentiation in mucoepidermoid carcinoma (MEC) is uncommon. Only twelve well-documented cases of oncocytic MEC have been reported previously all of which occurred in the parotid gland. To the best of our knowledge this is the first case of oncocytic mucoepidermoid carcinoma involving the submandibular salivary gland. The recognition of this entity is important, since most of the other primary oncocytic lesions of the salivary gland are benign.
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Abstract
Cells exposed to sustained endoplasmic reticulum (ER) stress undergo programmed cell death and display features typical of apoptosis, such as cysteine aspartyl protease (caspase) activation, cytochrome c release, and DNA fragmentation. Here, we show that the execution of cell death induced by ER stress is mediated via the proteasome. Inhibition of the proteasome by lactacystin prevented ER stress-induced degradation of Bcl-2, release of cytochrome c, processing of effector caspase-3, and exposure of phosphatidylserine. Owing to the ability of lactacystin to inhibit cytochrome c release, we propose that the pro-apoptotic activity of the proteasome lies upstream of mitochondrial activation. Thus, the proteasome serves as a principal mediator of ER stress-induced cell death in this system.
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Affiliation(s)
- L Egger
- The Buck Institute for Age Research, Novato, CA 94945, USA.
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Abstract
We present a case of papillary cystic low-grade adenocarcinoma of endolymphatic sac origin. These tumors are very rare and only a few cases have been reported in literature. They have a protracted clinical course causing progressive invasion and bony destruction. Radiologically, they appear as a heterogenous lobulated vascular mass, invading bone and compressing surrounding structures. Histologically, these tumors are composed of uniform population of cells, resembling normal endolymphatic sac epithelium. This causes considerable diagnostic difficulty. A strong index of suspicion along with clinical and radiological correlation is essential to arrive at a correct diagnosis. In some bilateral cases, association with von Hippel-Lindau disease has been noted. Radical mastoidectomy and temporal bone resection, which may sometimes necessitate sacrifice of cranial nerves, is the treatment of choice.
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Affiliation(s)
- Saurabh Malhotra
- Department of Pathology, Kasturba Medical College, Manipal, Karnataka, India.
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9
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Rao RV, Niazi K, Mollahan P, Mao X, Crippen D, Poksay KS, Chen S, Bredesen DE. Coupling endoplasmic reticulum stress to the cell-death program: a novel HSP90-independent role for the small chaperone protein p23. Cell Death Differ 2006; 13:415-25. [PMID: 16195741 PMCID: PMC1847409 DOI: 10.1038/sj.cdd.4401761] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [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: 11/09/2022] Open
Abstract
The endoplasmic reticulum (ER) is the principal organelle for the biosynthesis of proteins, steroids and many lipids, and is highly sensitive to alterations in its environment. Perturbation of Ca(2+) homeostasis, elevated secretory protein synthesis, deprivation of glucose or other sugars, altered glycosylation and/or the accumulation of misfolded proteins may all result in ER stress, and prolonged ER stress triggers cell death. Studies from multiple laboratories have identified the roles of several ER stress-induced cell-death modulators and effectors through the use of biochemical, pharmacological and genetic tools. In the present work, we describe the role of p23, a small chaperone protein, in preventing ER stress-induced cell death. p23 is a highly conserved chaperone protein that modulates HSP90 activity and is also a component of the steroid receptors. p23 is cleaved during ER stress-induced cell death; this cleavage, which occurs close to the carboxy-terminus, requires caspase-3 and/or caspase-7, but not caspase-8. Blockage of the caspase cleavage site of p23 was associated with decreased cell death induced by ER stress. Immunodepletion of p23 or inhibition of p23 expression by siRNA resulted in enhancement of ER stress-induced cell death. While p23 co-immunoprecipitated with the BH3-only protein PUMA (p53-upregulated modulator of apoptosis) in untreated cells, prolonged ER stress disrupted this interaction. The results define a protective role for p23, and provide further support for a model in which ER stress is coupled to the mitochondrial intrinsic apoptotic pathway through the activities of BH3 family proteins.
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Affiliation(s)
- RV Rao
- The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
- * Corresponding authors: RV Rao and DE Bredesen, The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA. Tel: +1 415 209 2000; Fax: + 1 415 209 2230; E-mail:
| | - K Niazi
- The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
| | - P Mollahan
- The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
| | - X Mao
- The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
| | - D Crippen
- The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
| | - KS Poksay
- The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
| | - S Chen
- The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
| | - DE Bredesen
- The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
- * Corresponding authors: RV Rao and DE Bredesen, The Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA. Tel: +1 415 209 2000; Fax: + 1 415 209 2230; E-mail:
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Valiathan M, Rao RV, Rao L, Jaffe ES, Pillai S. Nasal NK/T cell lymphoma mimicking a squamous cell carcinoma: a case report. INDIAN J PATHOL MICR 2005; 48:257-9. [PMID: 16758689] [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: 05/10/2023] Open
Abstract
A 48 year old female presented with extensive ulceration of the nasal septum of 8 months duration. Investigations confirmed the local nature of the disease. A biopsy revealed large zones of ischemic necrosis and abnormal lymphoid cells invading vessel walls and glandular structures. Florid squamous metaplasia, and pseudoepitheliomatous hyperplasia of mucosal epithelium mimicked squamous cell carcinoma and necrotising sialometaplasia. Immunohistochemistry and insitu hybridization confirmed the diagnosis of an EBV positive, Nasal NK/T cell lymphoma. A Pubmed/Medline search suggests that this is the first documented case from India.
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Affiliation(s)
- Manna Valiathan
- Department of Pathology, Kasturba Medical College, Manipal, Karnataka.
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11
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Abstract
The endoplasmic reticulum (ER) regulates protein synthesis, protein folding and trafficking, cellular responses to stress and intracellular calcium (Ca(2+)) levels. Alterations in Ca(2+) homeostasis and accumulation of misfolded proteins in the ER cause ER stress that ultimately leads to apoptosis. Prolonged ER stress is linked to the pathogenesis of several different neurodegenerative disorders. Apoptosis is a form of cell death that involves the concerted action of a number of intracellular signaling pathways including members of the caspase family of cysteine proteases. The two main apoptotic pathways, the death receptor ('extrinsic') and mitochondrial ('intrinsic') pathways, are activated by caspase-8 and -9, respectively, both of which are found in the cytoplasm. Recent studies point to the ER as a third subcellular compartment implicated in apoptotic execution. Here, we review evidence for the contribution of various cellular molecules that contribute to ER stress and subsequent cellular death. It is hoped that dissection of the molecular components and pathways that alter ER structure and function and ultimately promote cellular death will provide a framework for understanding degenerative disorders that feature misfolded proteins.
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Affiliation(s)
- R V Rao
- Buck Institute for Age Research, 8001 Redwood Boulevard, Novato, CA 94945, USA
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Desai N, Desai D, Ghag G, Waghela J, Rao RV, Sawant P. Giant mesenteric cyst of abdomen herniating into scrotum. Indian J Gastroenterol 2004; 23:74-5. [PMID: 15176544] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cystic mesenteric tumors are rare abdominal neoplasms. We report a 55-year-old man with recurrent benign mesothelioma arising from the left colonic mesentery and extending into the scrotal sac. He recovered well after excision of the abdominal and scrotal mass.
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Affiliation(s)
- Nutan Desai
- Department of Gastroenterology, Lokmanya Tilak Medical College, Mumbai 400 022.
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Castro-Obregón S, Del Rio G, Chen SF, Swanson RA, Frankowski H, Rao RV, Stoka V, Vesce S, Nicholls DG, Bredesen DE. A ligand-receptor pair that triggers a non-apoptotic form of programmed cell death. Cell Death Differ 2002; 9:807-17. [PMID: 12107824 DOI: 10.1038/sj.cdd.4401035] [Citation(s) in RCA: 59] [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] [Received: 07/27/2001] [Revised: 01/23/2002] [Accepted: 01/29/2002] [Indexed: 01/17/2023] Open
Abstract
Several receptors that mediate apoptosis have been identified, such as Fas and tumor necrosis factor receptor I. Studies of the signal transduction pathways utilized by these receptors have played an important role in the understanding of apoptosis. Here we report the first ligand-receptor pair-the neuropeptide substance P and its receptor, neurokinin-1 receptor (NK(1)R)-that mediates an alternative, non-apoptotic form of programmed cell death. This pair is widely distributed in the central and peripheral nervous systems, and has been implicated in pain mediation and depression, among other effects. Here we demonstrate that substance P induces a non-apoptotic form of programmed cell death in hippocampal, striatal, and cortical neurons. This cell death requires gene expression, displays a non-apoptotic morphology, and is independent of caspase activation. The same form of cell death is induced by substance P in NK(1)R-transfected human embryonic kidney cells. These results argue that NK(1)R activates a death pathway different than apoptosis, and provide a signal transduction system by which to study an alternative, non-apoptotic cell death program.
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Affiliation(s)
- S Castro-Obregón
- Buck Institute for Age Research, 8001 Redwood Boulevard, Novato, CA 94945, USA
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Abstract
BACKGROUND Extraskeletal myxoid chondrosarcoma is a rare tumor that usually occurs in the soft tissues of extremities. Cytologic features of chondrosarcoma arising from a rib and presenting as a breast mass were reported by Molyneux et al in 1995. However, to the best of our knowledge, the cytology of extraskeletal myxoid chondrosarcoma of the chest wall presenting as a breast mass has not been documented before. CASE A 30-year-old female presented with left-sided chest pain and a hard lump in the breast of two months' duration. Fine needle aspiration cytology was done, and a possible diagnosis of mucinous carcinoma or mixed tumor of the breast was suggested, with advice to prepare a frozen section before undertaking a radical procedure. On imprint cytology and frozen section a diagnosis of extraskeletal myxoid chondrosarcoma was made and confirmed by histopathology and immunohistochemistry. CONCLUSION It is rare for extraskeletal myxoid chondrosarcoma to occur in the chest wall. This problem is compounded by the fact that cells of extraskeletal myxoid chondrosarcoma which resemble epithelial cells, can very closely mimic some malignant breast tumors.
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Affiliation(s)
- Lakshmi Rao
- Departments of Pathology and Cardiothoracic Surgery, Kasturba Medical College and Hospital, Manipal, Karnataka, India
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15
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Rao RV, Hermel E, Castro-Obregon S, del Rio G, Ellerby LM, Ellerby HM, Bredesen DE. Coupling endoplasmic reticulum stress to the cell death program. Mechanism of caspase activation. J Biol Chem 2001; 276:33869-74. [PMID: 11448953 DOI: 10.1074/jbc.m102225200] [Citation(s) in RCA: 465] [Impact Index Per Article: 20.2] [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: 11/06/2022] Open
Abstract
The endoplasmic reticulum (ER) is the site of assembly of polypeptide chains destined for secretion or routing into various subcellular compartments. It also regulates cellular responses to stress and intracellular Ca(2+) levels. A variety of toxic insults can result in ER stress that ultimately leads to apoptosis. Apoptosis is initiated by the activation of members of the caspase family and serves as a central mechanism in the cell death process. The present study was carried out to determine the role of caspases in triggering ER stress-induced cell death. Treatment of cells with ER stress inducers such as brefeldin-A or thapsigargin induces the expression of caspase-12 protein and also leads to translocation of cytosolic caspase-7 to the ER surface. Caspase-12, like most other members of the caspase family, requires cleavage of the prodomain to activate its proapoptotic form. Caspase-7 associates with caspase-12 and cleaves the prodomain to generate active caspase-12, resulting in increased cell death. We propose that any cellular insult that causes prolonged ER stress may induce apoptosis through caspase-7-mediated caspase-12 activation. The data underscore the involvement of ER and caspases associated with it in the ER stress-induced apoptotic process.
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Affiliation(s)
- R V Rao
- Buck Institute for Age Research, 8001 Redwood Blvd, Novato, California 94945, USA
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Eskow E, Rao RV, Mordechai E. Concurrent infection of the central nervous system by Borrelia burgdorferi and Bartonella henselae: evidence for a novel tick-borne disease complex. Arch Neurol 2001; 58:1357-63. [PMID: 11559306 DOI: 10.1001/archneur.58.9.1357] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVES To investigate Bartonella henselae as a potential human tick-borne pathogen and to evaluate its role as a coinfecting agent of the central nervous system in the presence of neuroborreliosis. DESIGN Case report study. SETTING A primary health care center in Flemington, NJ, and the Department of Research and Development at Medical Diagnostic Laboratories LLC in Mt Laurel, NJ. SUBJECTS Two male patients (aged 14 and 36 years) and 2 female patients (aged 15 and 30 years, respectively) with a history of tick bites and Lyme disease. MAIN OUTCOME MEASURES Laboratory and diagnostic findings before and after antimicrobial therapy. RESULTS Patients residing in a Lyme-endemic area of New Jersey with ongoing symptoms attributed to chronic Lyme disease were evaluated for possible coinfection with Bartonella species. Elevated levels of B henselae-specific antibodies were found in these patients using the immunofluorescent assay. Bartonella henselae-specific DNA was detected in their blood. None of these patients exhibited the clinical characteristics of cat-scratch disease. Findings of cerebrospinal fluid analysis revealed the presence of both B henselae- and Borrelia burgdorferi-specific DNA. Bartonella henselae-specific DNA was also detected in live deer ticks obtained from the households of 2 of these patients. CONCLUSIONS Our data implicate B henselae as a potential human tick-borne pathogen. Patients with a history of neuroborreliosis who have incomplete resolution of symptoms should be evaluated for B henselae infection.
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Affiliation(s)
- E Eskow
- Hunterdon Medical Center, Flemington, NJ, USA
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Peel AL, Rao RV, Cottrell BA, Hayden MR, Ellerby LM, Bredesen DE. Double-stranded RNA-dependent protein kinase, PKR, binds preferentially to Huntington's disease (HD) transcripts and is activated in HD tissue. Hum Mol Genet 2001; 10:1531-8. [PMID: 11468270 DOI: 10.1093/hmg/10.15.1531] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [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: 11/12/2022] Open
Abstract
Fourteen neurological diseases have been associated with the expansion of trinucleotide repeat regions. These diseases have been categorized into those that give rise to the translation of toxic polyglutamine proteins and those that are untranslated. Thus far, compelling evidence has not surfaced for the inclusion of a model in which a common mechanism may participate in the pathobiology of both translated and untranslated trinucleotide diseases. In these studies we show that a double-stranded RNA-binding protein, PKR, which has previously been linked to virally-induced and stress-mediated apoptosis, preferentially binds mutant huntingtin RNA transcripts immobilized on streptavidin columns that have been incubated with human brain extracts. These studies also show, by immunodetection in tissue slices, that PKR is present in its activated form in both human Huntington autopsy material and brain tissue derived from Huntington yeast artificial chromosome transgenic mice. The increased immunolocalization of the activated kinase is more pronounced in areas most affected by the disease and, coupled with the RNA binding results, suggests a role for PKR activation in the disease process.
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Affiliation(s)
- A L Peel
- The Buck Institute, 8001 Redwood Boulevard, Novato, CA 94945, USA.
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Abstract
Clear cell carcinoma (CCC) of the larynx is extremely rare and to the best of our knowledge no such case has been reported in the paediatric age group. These tumours resemble the clear cell carcinoma of the major and minor salivary glands. We report such a lesion in a 15 years old boy presenting with hoarseness and an exophytic growth in the glottis. A frontolateral conservation laryngectomy with laryngoplasty was done and over 2 years follow-up has shown no evidence of loco-regional recurrence and he enjoys an acceptable voice.
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Affiliation(s)
- D R Nayak
- Department of ENT-Head & Neck Surgery, Kasturba Medical College, Manipal 576119, Karnataka, India.
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Abstract
BACKGROUND Infantile cartilaginous hamartoma of the rib is a rare condition occurring in newborn infants, with an incidence of 1 in 3,000 (0.03%) among primary bone tumor cases. Reports of this condition so far have presented the clinical, radiologic and histopathologic features. To the best of our knowledge, reports of the cytopathologic features have not been documented. In the present case report, clinical, radiologic and cytopathologic features and differential diagnosis are enumerated. CASE A 1-month-old, male infant presented with a chest wall mass with a clinical diagnosis of osteochondroma. On fine needle aspiration cytology, a diagnosis of infantile cartilaginous hamartoma of the rib was suggested; it was supplemented by the clinical history and radiologic findings. CONCLUSION Although rare, this condition ought to be kept in mind while dealing with infantile chest wall masses to avoid an erroneous diagnosis of malignancy, owing to its ominous cytopathologic features.
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Affiliation(s)
- L Rao
- Departments of Pathology and Orthopedics, Kasturba Medical College and Hospital, Manipal, Karnataka, India
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20
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Ding XQ, Rao RV, Kuntz SM, Holicky EL, Miller LJ. Impaired resensitization and recycling of the cholecystokinin receptor by co-expression of its second intracellular loop. Mol Pharmacol 2000; 58:1424-33. [PMID: 11093782 DOI: 10.1124/mol.58.6.1424] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [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: 11/22/2022] Open
Abstract
Intermolecular interaction represents an important theme in regulation of intracellular trafficking of organelles that can be interrupted by competitive overexpression of a relevant molecular domain. We attempted to identify the functional importance of intracellular domains of the cholecystokinin (CCK) receptor by their over-expression in receptor-bearing Chinese hamster ovary (CHO-CCKR) cell lines. Although clathrin-dependent endocytosis and recycling of this receptor are well-established (J Cell Biol 128:1029-1042, 1995), any influence of distinct receptor domains is not understood. In this work, constructs representing each of the intracellular domains of the CCK receptor were coexpressed with wild-type receptor, and stable clonal cell lines were selected. Each was characterized for ligand binding and agonist-stimulated biological activity (inositol 1,4,5-trisphosphate generation), desensitization, resensitization, receptor internalization, and recycling. Each cell line expressed normal CCK radioligand binding, signaling, internalization, and desensitization. Three independent cell lines that coexpressed the 25-residue second intracellular loop domain exhibited deficient resensitization. In morphological assessment of receptor trafficking, this construct was also shown to interfere with receptor recycling to the plasma membrane. As a control, recycling of an unrelated G protein-coupled receptor was demonstrated to occur normally in this cell line. These observations suggest that rather than representing passive cargo within an endosome, a receptor can influence its own trafficking within the cell.
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Affiliation(s)
- X Q Ding
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Rao RV, Holicky EL, Kuntz SM, Miller LJ. CCK receptor phosphorylation exposes regulatory domains affecting phosphorylation and receptor trafficking. Am J Physiol Cell Physiol 2000; 279:C1986-92. [PMID: 11078715 DOI: 10.1152/ajpcell.2000.279.6.c1986] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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: 11/22/2022]
Abstract
Agonist-stimulated phosphorylation of guanine nucleotide-binding protein (G protein)-coupled receptors has been recognized as an important mechanism for desensitization by interfering with coupling of the activated receptor with its G protein. We recently described a mutant of the CCK receptor that modified two of five key sites of phosphorylation (S260,264A) and eliminated agonist-stimulated receptor phosphorylation, despite normal ligand binding and signaling (20). As expected, this nonphosphorylated mutant had impaired rapid desensitization but was ultimately able to be desensitized by normal receptor internalization. Here we demonstrate that this mutant receptor is also defective in resensitization, with abnormal recycling to the cell surface. To explore this, another receptor mutant was prepared, replacing the same serines with aspartates to mimic the charge of serine-phosphate (S260,264D). This mutant was expressed in a Chinese hamster ovary cell line and shown to bind CCK normally. It had accelerated kinetics of signaling and desensitization and was phosphorylated in response to agonist occupation, with all other normal sites of phosphorylation modified. It was internalized like wild-type receptors and was resensitized and trafficked normally. This provides evidence for an additional important function for phosphorylation of G protein-coupled receptors. Phosphorylation may induce a conformational change in the receptor to expose other potential sites of phosphorylation and to expose domains involved in the targeting and trafficking of endosomes. The hierarchical phosphorylation of these sites may play a key role in receptor regulation.
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Affiliation(s)
- R V Rao
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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22
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Rao SC, Rao RV. Primary choriocarcinoma of stomach. INDIAN J PATHOL MICR 2000; 43:471-4. [PMID: 11344617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
A 45 year old patient wad admitted with pain abdomen and a palpable mass in the epigastrium of 3 months duration. Endoscopy revealed growth in the stomach and biopsy showed poorly differentiated Carcinoma. Distal radical subtotal gastrectomy was done. Histopathology revealed choriacarcinoma with Syncytiotrophoblastic and cytotrophoblastic and foci of adenocarcinoma. Postoperatively urine and serum had very high levels of beta-human chorionic gonogotrophins (B-HCG). Immunochemistry showed positivity for B-HCG. Clinically and on scan both the testis were normal. Because of its rarity, we are presenting this case with brief review of literature.
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Pai MR, Pai KN, Rao RV, Naik R, Baliga P. Connective tissue stromal changes in tumours and tumour-like lesions of the breast. INDIAN J PATHOL MICR 1999; 42:327-32. [PMID: 10862293] [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: 02/16/2023] Open
Abstract
Between June 1994 and December 1995, one hundred and fifteen tumours and tumour-like lesions of the breast were studied in the Department of Pathology, Kasturba Medical College, Mangalore. Neoplasms constituted 80.9% and tumour like lesions accounted for 19.13%. Among the tumours, 51.6% were benign and 48.4% were malignant. Tumour-like lesions included the entire spectrum of fibrocystic disease. Tumours were common between 2nd and 8th decades while tumour-like lesions were uncommon above 6th decade. Whereas benign tumours exhibited ground substance, collagen and reticulin fibres in varying amounts, tumour-like lesions and carcinoma showed more of collagen fibres and less of ground substance. Elastosis and lymphoplasmacytic infiltrate were prominent features in carcinomas rather than in benign lesions.
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Affiliation(s)
- M R Pai
- Department of Pathology, Kasturba Medical College, Mangalore
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Valiathan M, Bhat S, Rao G, Rao RV. Acanthameba keratitis. INDIAN J PATHOL MICR 1999; 42:385-6. [PMID: 10862306] [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: 02/16/2023] Open
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Go WY, Holicky EL, Hadac EM, Rao RV, Miller LJ. Identification of a domain in the carboxy terminus of CCK receptor that affects its intracellular trafficking. Am J Physiol 1998; 275:G56-62. [PMID: 9655684 DOI: 10.1152/ajpgi.1998.275.1.g56] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The carboxy-terminal region of many guanine nucleotide-binding protein (G protein)-coupled receptors contains important regulatory sequences such as an NP(x)2-3Y motif, a site of fatty acid acylation, and serine- and threonine-rich domains. The type A CCK receptor contains all of these, yet their significance has not been examined. We have, therefore, constructed a series of receptor site mutants and truncations that interfere with each of these motifs and expressed each in Chinese hamster ovary cells where they were studied for radioligand binding, cell signaling, receptor internalization, and intracellular trafficking. Each construct was synthesized and transported appropriately to the cell surface, where CCK bound with high affinity, elicited an inositol 1,4, 5-trisphosphate response, and resulted in internalization and normal trafficking. Thus modification or elimination of each of these established sequence motifs had no substantial effect on any of these parameters of receptor and cellular function. However, an additional construct that truncated the carboxy terminus, eliminating an additional 15-amino-acid segment devoid of any currently recognized sequence motifs, resulted in a marked change in receptor trafficking, with all other parameters of receptor function normal. This mutant receptor construct was delayed at the stage of early endosomes, delaying its progress to the lysosome-enriched perinuclear compartment from the rapid time course followed by wild-type receptor and all of the other constructs. It is proposed that this region of the CCK receptor tail contains a new motif important for intracellular receptor trafficking.
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Affiliation(s)
- W Y Go
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Bhanumathy CD, Rao RV, Balasubramanian AS. Serum butyrylcholinesterase of non-human primate shows amine sensitive aryl acyl amidase and metallopeptidase activities and characteristics similar to those of the human serum enzyme. Indian J Biochem Biophys 1998; 35:148-56. [PMID: 9803663] [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: 02/09/2023]
Abstract
Butyrylcholinesterase (BChE) was purified from monkey serum and the catalytic activities were examined. The enzyme has a molecular mass of approximately equal to 74 kDa as seen by SDS-gel electrophoresis. Monkey serum BChE also exhibits an amine sensitive aryl acylamidase (AAA) and a metallocarboxypeptidase activity. The tyramine activation of the aryl acylamidase activity and the metal chelator inhibition of the peptidase activity were characteristics similar to those of the human enzyme. Studies on 65Zn2+ binding and zinc chelate Sepharose chromatography showed that monkey serum BChE and human serum BChE have similar characteristics. Limited alpha chymotrypsin digestion of monkey serum BChE followed by Sephadex gel chromatography cleaved the enzyme into a 36 kDa fragment exhibiting peptidase activity. However the 20 kDa fragment corresponding to cholinesterase and aryl acylamidase activity was not detectable possibly due to the unstable nature of the fragment. Immunological studies showed that a polyclonal antibody against human serum BChE cross reacted with monkey serum BChE. The identical nature of the catalytic activities of human serum BChE and monkey serum BChE supports the postulate that all three catalytic activities co-exist in the same enzyme. This is the first time that purification and characterisation of the monkey serum BChE which has the highest sequence identity and immunological identity with that of human serum BChE, is being reported.
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Affiliation(s)
- C D Bhanumathy
- Neurochemistry Laboratory, Christian Medical College and Hospital, Vellore, India
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Smeets RL, Rao RV, van Emst-de Vries SE, De Pont JJ, Miller LJ, Willems PH. Reduced cholecystokinin receptor phosphorylation and restored signalling in protein kinase C down-regulated rat pancreatic acinar cells. Pflugers Arch 1998; 435:422-8. [PMID: 9426300 DOI: 10.1007/s004240050533] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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: 02/05/2023]
Abstract
Receptor phosphorylation in response to agonist stimulation is a key regulatory principle in signal transduction. Previous work has suggested the concerted action of protein kinase C (PKC) and a staurosporine-insensitive receptor kinase in homologous phosphorylation of the cholecystokinin (CCK) receptor in freshly isolated rat pancreatic acinar cells [Gates, Ulrich, Miller (1993) Am J Physiol 264:G840-G847]. The present study shows that down-regulation of PKC by prolonged (2 h) treatment with 0.1 muM 12-O-tetradecanoylphorbol-13-acetate (TPA) markedly reduced basal CCK receptor phosphorylation as well as that induced by TPA (0.1 muM) and cholecystokinin-(26-33)-peptide amide (CCK8, 0.1 muM). The phosphorylation level reached was the same with both stimulants and equalled basal phosphorylation in untreated control cells. The absence of any CCK8-stimulated phosphorylation reflecting the activity of a putative staurosporine-insensitive receptor kinase raises the intriguing possibility that a basal level of PKC-mediated receptor phosphorylation is required for the action of such a receptor kinase. Immunoblot analysis revealed that the decrease in receptor phosphorylation coincided with a marked reduction of PKC-alpha and, to a lesser extent, PKC-epsilon. In addition, TPA-induced inhibition of the increase in cytosolic free Ca2+ concentration ([Ca2+]i) evoked by the high-affinity CCK receptor agonist JMV-180 was completely reversed. The time-course of recovery closely matched that of the reduction of PKC-alpha. Finally, digital imaging microscopy of individual PKC down-regulated cells revealed a marked increase in the duration of JMV-180-evoked oscillatory changes in [Ca2+]i. Taken together, the present findings are in agreement with the idea that PKC-alpha-mediated receptor phosphorylation leads to a shortening of the duration of the [Ca2+]i oscillations and eventually to inhibition of high-affinity Ca2+ signalling through the native CCK receptor in pancreatic acinar cells.
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Affiliation(s)
- R L Smeets
- Department of Biochemistry, University of Nijmegen, PO Box 9101, NL-6500 HB Nijmegen, The Netherlands
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Rao RV, Hadac EM, Roettger BF, Miller LJ. Cholecystokinin-induced desensitization, receptor phosphorylation, and internalization in the CHP212 neuroblastoma cell line. J Neurochem 1997; 68:2356-62. [PMID: 9166728 DOI: 10.1046/j.1471-4159.1997.68062356.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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: 02/04/2023]
Abstract
Agonist stimulation of cells often results in desensitization of the response, to protect the cell from overstimulation. We have previously shown that the type A cholecystokinin (CCK) receptor on the pancreatic acinar cell and on the model CHO-CCKR cell line undergoes desensitization in response to CCK, with receptor phosphorylation and internalization playing key roles. Although these mechanisms contribute in a cell-specific manner, no analogous information exists for the CCK receptor expressed on neuronal cells, where in vivo data demonstrate a particularly sensitive response to CCK. The present study was designed to explore CCK receptor desensitization in the CHP212 neuroblastoma cell line, focusing on inositol 1,4,5-trisphosphate (IP3) responses to CCK and on recognized molecular and cellular mechanisms of desensitization. CCK promptly stimulated IP3 responses in these cells, with hormonal responsiveness rapidly and completely desensitized. Both receptor phosphorylation and internalization were observed to occur, with the former occurring most rapidly and likely being responsible for the earliest desensitization observed. Although the time course of receptor phosphorylation and dephosphorylation, and the groups of kinases involved in the neuroblastoma cell line, were most similar to those in the pancreatic cell, the movement of the agonist-bound receptor in these cells was quite different from that in the pancreatic cell and most similar to that in the CHO-CCKR cell line. This hybrid response supports the cell-specific nature of CCK receptor regulation and provides an important system to explore the molecular determinants of these processes.
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Affiliation(s)
- R V Rao
- Center for Basic Research in Digestive Diseases, Department of Biochemistry and Molecular Biology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, U.S.A
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29
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Rajan MT, Jagannatha Rao KS, Mamatha BM, Rao RV, Shanmugavelu P, Menon RB, Pavithran MV. Quantification of trace elements in normal human brain by inductively coupled plasma atomic emission spectrometry. J Neurol Sci 1997; 146:153-66. [PMID: 9077512 DOI: 10.1016/s0022-510x(96)00300-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [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: 02/04/2023]
Abstract
Eight normal human brain autopsy samples were analyzed for Na, K, P, Ca, Mg, Si, Cr, Cu, Ni, Zn, Fe, Al, Cd, Pb and As in 12 regions of brain (frontal cerebrum, temporal cerebrum, parietal cerebrum, somatosensory cortex, occipital cerebrum, cerebellum, mid-brain, pons, hypothalamus, thalamus, hippocampus and medulla oblongata) using inductively coupled plasma atomic emission spectrometry (ICPAES). The distribution of these 15 elements varied significantly from region to region of the brain. Potassium was most abundant in nearly all regions of the brain, followed by sodium and phosphorus (mg/g). The concentration of Al was found to be comparatively high and varied in different areas of the brain (58-196 microg/g). Moderate levels of Pb, Cd and As were observed in different regions. Ratios of Al to Fe were found to be high in temporal cerebrum (8.07) and hippocampus (9.05) and these two regions are significantly involved in Alzheimer's disease. The concentration of Na in mole percentage showed an inverse correlation with that of K, Ca, Mg, Fe and Cr. Direct correlation was observed in the concentration of all analyzed elements, which indicated for the first time the direct dependency of concentration of trace elements in one brain region to other regions. The mole ratios between different elements in different brain regions and total amounts of the elements in an average weight of 1.4 kg human brain were also computed. The present study provides new and in-depth data which may be used as base line data for normal human brains.
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Affiliation(s)
- M T Rajan
- Department of Biochemistry and Nutrition, Central Food Technological Research Institute, Mysore, India
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30
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Rao RV, Roettger BF, Hadac EM, Miller LJ. Roles of cholecystokinin receptor phosphorylation in agonist-stimulated desensitization of pancreatic acinar cells and receptor-bearing Chinese hamster ovary cholecystokinin receptor cells. Mol Pharmacol 1997; 51:185-92. [PMID: 9203622 DOI: 10.1124/mol.51.2.185] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [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: 02/04/2023] Open
Abstract
Receptor phosphorylation has been implicated in desensitization responses to some agonist ligands, in which receptors may become uncoupled from G proteins and move into cellular compartments inaccessible to hydrophilic ligands. Understanding of the linkage between these processes, however, has come largely from recombinant receptor-bearing cell systems with consensus sites of kinase action mutagenized. We recently established methodology permitting direct assessment of sites of phosphorylation of the cholecystokinin receptor (CCKR) in its native milieu in the pancreatic acinar cell and in a Chinese hamster ovary (CHO)-CCKR cell line (1, 2). Although CCK binding leads to phosphorylation of serine residues within the third intracellular loop of the receptor in both cell types, there are clear differences in the time course of phosphorylation, in the balance of action of kinases and a receptor phosphatase, and in a few of the distinct sites phosphorylated. In this work, we have directly assessed the inositol 1,4,5-triphosphate responses to CCK and desensitization of these responses in both cells. CHO cell lines expressing receptor mutants with protein kinase C consensus sites modified were also studied. CCK-stimulated inositol 1,4,5-triphosphate responses in both cells expressing wild-type receptors were rapidly and completely desensitized, associated with the onset of receptor phosphorylation. However, despite maintenance of the phosphorylated state of the receptor in the CHO-CCKR cell and its dephosphorylation returning the receptor to its basal state in the acinar cell, desensitization continued to be present in both. Mutagenesis of Ser260 and Ser264 to alanines individually reduced receptor phosphorylation by approximately 50%, whereas the dual mutant completely eliminated agonist-stimulated phosphorylation. Because other sites of phosphorylation were still intact in this construct, this raises the possibility of hierarchical phosphorylation with these two sites key in making other sites accessible to kinases. Constructs modifying Ser264 delayed the onset of desensitization, whereas all constructs proceeded to achieve complete desensitization by 10 min. Receptor internalization occurred independent of its phosphorylation state in the CHO cell lines, explaining the desensitization observed. In the acinar cell in which the receptor remains on the cell surface after agonist occupation, we postulate that receptor insulation achieves similar uncoupling from G protein association as is achieved by receptor phosphorylation early after agonist occupation.
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Affiliation(s)
- R V Rao
- Center for Basic Research in Digestive Diseases and the Department of Biochemistry and Molecular Biology, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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31
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Ozcelebi F, Rao RV, Holicky E, Madden BJ, McCormick DJ, Miller LJ. Phosphorylation of cholecystokinin receptors expressed on Chinese hamster ovary cells. Similarities and differences relative to native pancreatic acinar cell receptors. J Biol Chem 1996; 271:3750-5. [PMID: 8631990 DOI: 10.1074/jbc.271.7.3750] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [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: 02/01/2023] Open
Abstract
Phosphorylation of G protein-coupled receptors is an established mechanism for desensitization in response to agonist stimulation. We previously reported phosphorylation of the pancreatic acinar cell cholecystokinin (CCK) receptor and the establishment of two-dimensional phosphopeptide mapping of its sites of phosphorylation (Ozcelebi, F., and Miller, L. J. (1995) J. Biol. Chem. 270, 3435-3441). Here, we use similar techniques to map sites of phosphorylation of the same receptor expressed on a stable receptor-bearing Chinese hamster ovary (CHO)-CCKR cell line. Like the native cell, the CHO-CCKR cell receptor was phosphorylated in response to agonist stimulation in a concentration-dependent manner; however, the time course was quite different. CHO-CCKR cell receptor phosphorylation increased progressively to a plateau after 15 min, while in the acinar cell it peaks within 2 min and returns to baseline over this interval. There were distinct qualitative and quantitative differences in the sites of phosphorylation of the two receptor systems. One site previously attributed to action of a staurosporine-insensitive kinase in the acinar cell was absent in the CHO-CCKR cell. Site-directed mutagenesis was utilized to eliminate predicted sites of protein kinase C action, but only two of four such sites affected the phosphopeptide map of this receptor. Chemical and radiochemical sequencing were performed on these and other phosphopeptides which were present in both the CHO-CCKR cells and agonist-stimulated pancreatic acinar cells to provide direct evidence for the phosphorylation sites actually utilized. Thus, these data support the usefulness and limitations of a model cell system in studying receptor phosphorylation and desensitization.
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Affiliation(s)
- F Ozcelebi
- Center for Basic Research in Digestive Diseases and the Department of Biochemistry and Molecular Biology, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Anupindi L, Sahoo R, Rao RV, Verghese G, Rao PV. Microfilariae in bronchial brushing cytology of symptomatic pulmonary lesions. A report of two cases. Acta Cytol 1993; 37:397-9. [PMID: 8498141] [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: 01/31/2023]
Abstract
Two cases of pulmonary filariasis with atypical clinical and radiologic features without significant eosinophilia are presented. A diagnosis of pulmonary filariasis could not have been made without bronchial brush cytology, which showed sheathed microfilariae of Wuchereria bancrofti. Both cases responded well to antifilarial treatment, indicating that the microfilariae were not an incidental finding but were responsible for the symptoms and radiologic lesions.
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Affiliation(s)
- L Anupindi
- Department of Pathology, Kasturba Medical College, Manipal, South Karnataka, India
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Rao RV, Balasubramanian AS. The peptidase activity of human serum butyrylcholinesterase: studies using monoclonal antibodies and characterization of the peptidase. J Protein Chem 1993; 12:103-10. [PMID: 8427627 DOI: 10.1007/bf01024921] [Citation(s) in RCA: 15] [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] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Purified human serum butyrylcholinesterase, which exhibits cholinesterase, aryl acylamidase, and peptidase activities, was cross-reacted with two different monoclonal antibodies raised against human serum butyrylcholinesterase. All three activities were immunoprecipitable at different dilutions of the two monoclonal antibodies. At the highest concentration of the antibodies used, nearly 100% of all three activities were precipitated, and could be recovered to 90-95% in the immunoprecipitate. The peptidase activity exhibited by the purified butyrylcholinesterase was further characterized using both Phe-Leu and Leu-enkephalin as substrates. The pH optimum of the peptidase was in the range of 7.5-9.5 and the divalent cations Co2+, Mn2+, and Zn2+ stimulated its activity. EDTA and other metal complexing agents inhibited its activity. Thiol agents and -SH group modifiers had no effect. The serine protease inhibitors, diisopropylfluorophosphate and phenyl methyl sulfonyl fluoride, did not inhibit. When histidine residues in the enzyme were modified by diethylpyrocarbonate, the peptidase activity was not affected, but the stimulatory effect of Co2+, Mn2+, and Zn2+ disappeared, suggesting the involvement of histidine residues in metal ion binding. These general characteristics of the peptidase activity were also exhibited by a 50 kD fragment obtained by limited alpha-chymotrypsin digestion of purified butyrylcholinesterase. Under all assay conditions, the peptidase released the two amino acids, leucine and phenylalanine, from the carboxy terminus of Leu-enkephalin as verified by paper chromatography and HPLC analysis. The results suggested that the peptidase behaved like a serine, cysteine, thiol-independent metallopeptidase.
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Affiliation(s)
- R V Rao
- Department of Neurological Sciences, Christian Medical College and Hospital Vellore, India
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Rao RV, Anupindi L, Chatterjee A, Varghese GK, Krishnanand BR. Filarial nephritis: a cause of nephrotic syndrome. Trop Geogr Med 1993; 45:180-181. [PMID: 8236471] [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: 05/22/2023]
Abstract
A 26-year-old male presented with oedema, massive albuminuria and microscopic haematuria. Kidney biopsy revealed enlarged cellular glomeruli infiltrated by polymorphs and eosinophils with focal fibrin deposits along the basement membrane. Microfilariae were seen in the lumen of few glomerular capillaries. Antistreptolysin titre was negative. The absence of other aetiological factors and presence of microfilariae within glomeruli suggests that nephrotic syndrome may be due to a filarial nephritis.
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Affiliation(s)
- R V Rao
- Kasturba Medical College, South Karnataka, India
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Vidyasagar MS, Fernandes DJ, Kasturi DP, Akhileshwaran R, Rao K, Rao S, Rao RV, Solomon JG. Radiotherapy and verrucous carcinoma of the oral cavity. A study of 107 cases. Acta Oncol 1992; 31:43-7. [PMID: 1586504 DOI: 10.3109/02841869209088264] [Citation(s) in RCA: 29] [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] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
One hundred and seven cases of oral verrucous carcinoma treated primarily with radiotherapy at Kasturba Hospital, Manipal, India between 1977 and 1987 were analysed concerning location within the oral cavity, clinical extent, and effectiveness of radiotherapy. The most common site was the buccal mucosa followed by the buccogingival sulcus. Only 13.2% of the patients presented with T1 or T2 tumours and 32.7% had clinically negative nodes. Biopsy had to be repeated more than once in 22 patients to get confirmation of invasive carcinoma. The 5-year survival rate was 35% for stage III and 26% for stage IV. The treatment results with radiotherapy were comparable with those for ordinary squamous cell carcinoma of the oral cavity. It is felt that the treatment policy for verrucous carcinoma can be the same as for ordinary squamous cell carcinoma. In order to prevent delay in diagnosis and treatment, proper cooperation between the treating oncologist and the pathologist is essential.
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Affiliation(s)
- M S Vidyasagar
- Department of Radiotherapy, Kasturba Medical College, Hospital, Manipal, India
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Rao RV, Balasubramanian AS. Localization of the peptidase activity of human serum butyrylcholinesterase in a approximately 50-kDa fragment obtained by limited alpha-chymotrypsin digestion. Eur J Biochem 1990; 188:637-43. [PMID: 2331989 DOI: 10.1111/j.1432-1033.1990.tb15445.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Purified human serum butyrylcholinesterase (approximately 90-kDa subunit) is known to exhibit aryl acylamidase and peptidase activity. Limited alpha-chymotrypsin digestion of the purified butyrylcholinesterase gave three major protein fragments of approximately 50 kDa, approximately 21 kDa and approximately 20 kDa. In our earlier studies [Rao and Balasubramanian (1989) Eur. J. Biochem. 179, 639-644] we characterized the approximately 20-kDa fragment and showed that it exhibited both butyrylcholinesterase and aryl acylamidase activities. In the present studies the approximately 50-kDa fragment is characterized. This fragment, after isolation by Sephadex G-75 chromatography from a chymotryptic digest of purified butyrylcholinesterase, exhibited only peptidase activity and was devoid of cholinesterase and aryl acylamidase activities. It could bind to a column of Ricinus communis agglutinin bound to Sepharose, indicating its glycosylated nature and the presence of galactose. The peptidase activity in the approximately 50-kDa fragment could be immuno-precipitated by a polyclonal antibody raised against purified butyrylcholinesterase. SDS-gel electrophoresis of this fragment isolated by R. communis agglutinin-Sepharose and Sephadex G-75 chromatography showed a protein band of approximately 50 kDa by silver staining. Amino-terminal sequence analysis of the approximately 50-kDa fragment gave the sequence of Gly-Pro-Thr-Val-Asp which corresponded to amino acid residues 291-295 in the butyrylcholinesterase sequence [Lockridge et al. (1987) J. Biol. Chem. 262, 549-557]. The combined results suggested that alpha-chymotrypsin digestion of human serum butyrylcholinesterase resulted in the formation of a approximately 20-kDa fragment exhibiting both cholinesterase and aryl acylamidase activities and a approximately 50-kDa fragment exhibiting only peptidase activity.
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Affiliation(s)
- R V Rao
- Department of Neurological Sciences, Christian Medical College and Hospital, Vellore, India
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Rao RV, Satpathy A. Theoretical evaluation of neutron scattering intensities, partial structure factors, and diffusion coefficients of the alloy of the peculiar metal Bi in Cu-Bi alloy. Phys Rev B Condens Matter 1990; 41:995-1002. [PMID: 9993795 DOI: 10.1103/physrevb.41.995] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Rao RV, Gnanamuthu C, Balasubramanian AS. Human cerebrospinal fluid acetylcholinesterase and butyrylcholinesterase. Evidence for identity between the serum and cerebrospinal fluid butyrylcholinesterase. Clin Chim Acta 1989; 183:135-45. [PMID: 2791303 DOI: 10.1016/0009-8981(89)90329-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [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: 01/02/2023]
Abstract
Human cerebrospinal fluid contained both acetylcholinesterase (EC 3.1.1.7) and butyrylcholinesterase (EC 3.1.1.8) and they were estimated in the presence of selective inhibitors. Butyrylcholinesterase of human cerebrospinal fluid was similar to human serum butyrylcholinesterase in its electrophoretic mobility, glycoprotein nature and tyramine activation of the aryl acylamidase (EC 3.5.1.13) activity exhibited by butyrylcholinesterase. Moreover antibody raised against human serum purified butyrylcholinesterase could completely immunoprecipitate butyrylcholinesterase from human cerebrospinal fluid without affecting acetylcholinesterase. It is suggested that a useful method for the precise determination of acetylcholinesterase in human cerebrospinal fluid would be removal of butyrylcholinesterase by immunoprecipitation using antibody raised against human serum butyrylcholinesterase.
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Affiliation(s)
- R V Rao
- Department of Neurological Sciences, Christian Medical College and Hospital, Vellore, India
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Rao RV, Balasubramanian AS. Isolation of a galactose-free 20-kDa fragment exhibiting butyrylcholine esterase and aryl acylamidase activity from human serum butyrylcholine esterase by limited alpha-chymotrypsin digestion. Eur J Biochem 1989; 179:639-44. [PMID: 2646120 DOI: 10.1111/j.1432-1033.1989.tb14595.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Purified human serum butyrylcholine esterase (approximately 90-kDa subunit), which also exhibits aryl acylamidase activity, was subjected to limited alpha-chymotrypsin digestion. Three major protein fragments of approximately 50 kDa, approximately 21 kDa and approximately 20 kDa were found to be produced, as observed by SDS-gel electrophoresis of the chymotryptic digest. The purified butyrylcholine esterase could fully bind to a Ricinus-communis-agglutinin-Sepharose column but after chymotryptic digestion about 15-20% of the enzyme activity remained unbound and was recovered in the run-through fractions. Sephadex G-75 chromatography of the chymotryptic digest showed an enzymatically active fragment eluted at an approximate molecular mass of 20 kDa, apart from the undigested butyrylcholine esterase eluted at the void volume. The butyrylcholine esterase fragment that did not bind to Ricinus communis agglutinin also was eluted at an approximate molecular mass of 20 kDa from a Sephadex G-75 column. This enzymatically active low-molecular-mass fragment from Sephadex G-75 chromatography showed a single protein band of approximately 20 kDa on SDS-gel electrophoresis. Neutral sugar analysis of the approximately 20 kDa fragment showed the presence of mannose only, whereas the undigested butyrylcholine esterase showed the presence of both mannose and galactose. Amino-terminal-sequence analysis of the approximately 20 kDa fragment showed the sequence Arg-Val-Gly-Ala-Leu, which agrees with amino acid residues 147-151 reported for human serum butyrylcholine esterase [Lockridge et al. (1987) J. Biol. Chem. 262, 549-557]. Both cholinesterase and aryl acylamidase activities were co-eluted in all chromatographic procedures. The results suggested that limited alpha-chymotrypsin digestion of human serum butyrylcholine esterase resulted in the formation of a approximately 20-kDa enzymatically active fragment with Arg147 as its N-terminal residue and which was devoid of galactose.
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Affiliation(s)
- R V Rao
- Department of Neurological Sciences, Christian Medical College and Hospital, Vellore, India
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Pratap S, Nalini V, Rao RV, Rao PL. Sirenomelia: a case report. Asia Oceania J Obstet Gynaecol 1987; 13:265-7. [PMID: 3435278 DOI: 10.1111/j.1447-0756.1987.tb00261.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Dhand R, Sehgal S, Rao RV, Raghunandharao D, Malik SK. Prevalence of antinuclear antibodies in isoniazid treated patients. J Assoc Physicians India 1987; 35:113-5. [PMID: 3500944] [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: 01/06/2023]
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Rao RV. Vascular surgery and accreditation. Ann Surg 1987; 205:103-4. [PMID: 3800455 PMCID: PMC1492884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Abstract
A 52-year-old male had a biopsy done from a tongue lesion and was reported to have primary haemangiosarcoma. The case has been reported because of the rarity of this tumour.
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Chowdhury AR, Chinoy NJ, Gautam AK, Rao RV, Parikh DJ, Shah GM, Highland HN, Patel KG, Chatterjee BB. Effect of lead on human semen. Adv Contracept Deliv Syst 1986; 2:208-10. [PMID: 12280508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
Semen qualities were studied in workers with an average age of 30 years and occupationally exposed to lead in a printing press. Another sample with the same average age but not exposed to lead were taken as control subjects. The average lead content in blood and seminal plasma of the exposed group were 42.5 mcg/100 ml and 14.80 mcg/100 ml, respectively. Their sperm counts and percentage of motile sperm were significantly affected. Significantly higher percentages of abnormal spermatozoa were also observed in these semen samples. The levels of seminal acid phosphatase, succinic dehydrogenase, and fructose in them were also significantly found to be low compared with those from the unexposed subjects. Cytochemical study of sperm head DNA in the exposed groups showed a low surface reaction.
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Aithala G, Baliga M, Rao RV, Venkatesh A. Myelofibrosis in infancy. Indian Pediatr 1986; 23:307-9. [PMID: 3744501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Naik RP, Srinivas CR, Rao RV. Thickening of peripheral nerves in neurofibromatosis. Indian J Lepr 1985; 57:876-8. [PMID: 3938989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A rare case of multiple neurofibromatosis (von Recklinghausen's Disease) with bilateral, uniform and gross enlargement of peripheral nerves simulating nerve thickening in leprosy is reported. The case also showed characteristic palmar melanotic macules.
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Ramnarayan K, Rao RV, Nayak RG, Rajan N, Pai SU. Colitis cystica profunda. Indian J Gastroenterol 1985; 4:109-10. [PMID: 3845910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Nayak RG, Ramnarayan K, Rao RV, Shenoy MG, Agarwal BK. Histoplasma colitis. INDIAN J PATHOL MICR 1985; 28:163-5. [PMID: 3835118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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Nayak RG, Ramnarayan K, Rao RV, Shenoy MG. A case of histoplasma posthitis. Trop Geogr Med 1984; 36:309-11. [PMID: 6506213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The present report describes a case of disseminated histoplasmosis with involvement of the prepuce. Phimosis resulting from histoplasma posthitis is exceedingly rare and hence being documented.
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Parameswara YR, Naik RPCR, Nayak RG, Rao RV. Kyrle's Disease. Indian J Dermatol Venereol Leprol 1982; 48:49-52. [PMID: 28193990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Three cases of Kyrle's disease are reported. AR the three cases showed lesions with typical morphology and histology. In one instance the disease was present in the earlier generation. An interesting feature is the observation of a Koebner- like phenomenon.
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