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Kumar SA, Cheng W. A hypothesis: Bitter taste receptors as a therapeutic target for the clinical symptoms of SARS-CoV-2. Pharmazie 2021; 76:43-54. [PMID: 33714279 DOI: 10.1691/ph.2021.0840] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has paralysed the livelihood of the global population by inflicting higher mortality among the affected patients. Nearly the entire human physiological system can get disrupted by the virulence of SARS-CoV-2, which exemplifies the significance of discovering a potential drug target. Similar to angiotensin-converting enzyme 2 (ACE2), bitter taste receptors (T2Rs) unequivocally expressed on all vital human organs, particularly on nasal/oral respiratory tract, gastrointestinal organs, innate immune cells, heart, brain and urogenital cells are susceptible to SARS-CoV-2 virulence. Activation of T2Rs by bitter agonists restores vital functions to these organs via activation of large conductance, Ca2+-dependent potassium (K+) channels (BKca), and inducible nitric oxide synthase. T2R activation in the gustatory system can act as the first defence mechanism, primarily preventing or mitigating SARS-CoV-2 entry to the respiratory tract. Moreover, T2R activation is crucial for the improved vasodilation accompanied by the attenuation of systemic inflammation; hyper-innate immune responses; gastrointestinal disorders; defective neurological functions; acute kidney injury; and impotency witnessed in severe SARS-CoV-2 cases. This review discusses the potential for bitter taste receptors to act as drug targets for SARS-CoV-2 symptoms and the use of existing bitter agonists to restore T2R function.
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Affiliation(s)
- S A Kumar
- Henan Provincial Key Laboratory of Children's Genetics and Metabolic Diseases, Henan Children's Hospital, Zhengzhou, Henan, China; Department of Endocrinology and Metabolism, Henan Children's Hospital, Zhengzhou, Henan, China;,
| | - Weyland Cheng
- Henan Provincial Key Laboratory of Children's Genetics and Metabolic Diseases, Henan Children's Hospital, Zhengzhou, Henan, China; Department of Orthopaedic Surgery, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, Henan, China;,
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Sheetal S, Kumar SA, Thomas R. Isolated truncal contrapulsion as a rare presentation of acute thalamic infarct. J Postgrad Med 2020; 66:212-214. [PMID: 33078722 PMCID: PMC7819379 DOI: 10.4103/jpgm.jpgm_706_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Infarcts involving the thalamus can yield many deficits, including sensory syndromes, altered consciousness, and cognitive disturbances, depending on the thalamic vascular territory involved. Isolated truncal contrapulsion due to pure thalamic infarct has been rarely reported. Truncal lateropulsion is a compelling sensation of being pulled toward one side that cannot be explained by weakness or limb ataxia. It is commonly reported in lateral medullary infarcts. It may occur with lesions that involve the peripheral vestibular system, brainstem, cerebellum, basal ganglia, ponto-mesencephalic, and thalamic lesions. We hereby report a 64-year-old woman who presented with truncal contrapulsion as the sole manifestation of an acute right lateral thalamic infarct.
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Affiliation(s)
- S Sheetal
- Department of Neurology, Pushpagiri Institute of Medical Sciences and Research, Tiruvalla, Kerala, India
| | - S A Kumar
- Department of Neurology, Pushpagiri Institute of Medical Sciences and Research, Tiruvalla, Kerala, India
| | - R Thomas
- Department of Neurology, Pushpagiri Institute of Medical Sciences and Research, Tiruvalla, Kerala, India
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Reddy SK, Kumar SA, Kumar VD, Ganapaty S. Anti-inflammatory and Analgesic Activities of <i>Amorphophallus bulbifer</i> (Roxb) <i>Kunth</i> Whole Plant. TROP J PHARM RES 2013. [DOI: 10.4314/tjpr.v11i6.14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Kapoor R, Kapur P, Kumar SA, Alex D, Ranka S, Palta J. SU-E-T-211: Peer Review System for Ensuring Quality of Radiation Therapy Treatments. Med Phys 2012; 39:3751-3752. [PMID: 28517327 DOI: 10.1118/1.4735272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To demonstrate a Web-based electronic peer review system that has the potential to improve quality of care for radiation therapy patients. The system provides tools that allow radiation oncologists to seek peer review of target and critical structure delineation, treatment plans, and share clinical data with peers to optimize radiation therapy treatments. MATERIAL AND METHODS Peer review of radiation therapy treatment planning data prior to its initiation improves the quality of radiation therapy and clinical outcomes. Web-based access to radiation therapy treatment planning data and medical records mitigate existing geographical and temporal constraints. With internet access, the healthcare provider can access the data from any location and review it in an interactive and collaborative manner. Interoperability standard like DICOM-RT and IHE-RO compliant RT Systems have facilitated the design and implementation of PRS with Silverlight Web technology, .net Framework and SQL Server. Local DICOM-RT archive and cloud based services are deployed to facilitate remote peer reviews. RESULTS To validate the PRS system, we tested the system for 100 patients with Philips Pinnacle v 9.0 and Varian Eclipse v 8.9 treatment planning system (TPS). We transmitted the DICOM RT data from the TPS to the cloud based services via the PRS local DICOM RT Archive. Various CT simulation based parameters such as orientation of CT, properties of RT structures etc. were compared between the TPS and PRS system. Data integrity of other parameters such as patient demographics (patient name, ID, attending physician etc.) and dose volume related parameters were also evaluated. Such rigorous testing allowed us to optimize the functionalities and clinical implementation of the PRS. CONCLUSIONS We believe that the PRS will improve the quality and safety of a broad spectrum of radiation therapy patients treated in underserved areas while discouraging the overutilization of expensive radiation treatment modalities. This research and development project is supported by the James and Ester King Biomedical Research Program grant # RC1-09KW-09-26829.
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Affiliation(s)
- R Kapoor
- University of Florida Health Science Center, Gainesville, FL
| | - P Kapur
- University of Florida Health Science Center, Gainesville, FL
| | - S A Kumar
- University of Florida Health Science Center, Gainesville, FL
| | - D Alex
- University of Florida Health Science Center, Gainesville, FL
| | - S Ranka
- University of Florida Health Science Center, Gainesville, FL
| | - J Palta
- University of Florida Health Science Center, Gainesville, FL
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Wu W, Cheng Y, Keller CA, Ernst J, Kumar SA, Mishra T, Morrissey C, Dorman CM, Chen KB, Drautz D, Giardine B, Shibata Y, Song L, Pimkin M, Crawford GE, Furey TS, Kellis M, Miller W, Taylor J, Schuster SC, Zhang Y, Chiaromonte F, Blobel GA, Weiss MJ, Hardison RC. Dynamics of the epigenetic landscape during erythroid differentiation after GATA1 restoration. Genome Res 2011; 21:1659-71. [PMID: 21795386 DOI: 10.1101/gr.125088.111] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Interplays among lineage-specific nuclear proteins, chromatin modifying enzymes, and the basal transcription machinery govern cellular differentiation, but their dynamics of action and coordination with transcriptional control are not fully understood. Alterations in chromatin structure appear to establish a permissive state for gene activation at some loci, but they play an integral role in activation at other loci. To determine the predominant roles of chromatin states and factor occupancy in directing gene regulation during differentiation, we mapped chromatin accessibility, histone modifications, and nuclear factor occupancy genome-wide during mouse erythroid differentiation dependent on the master regulatory transcription factor GATA1. Notably, despite extensive changes in gene expression, the chromatin state profiles (proportions of a gene in a chromatin state dominated by activating or repressive histone modifications) and accessibility remain largely unchanged during GATA1-induced erythroid differentiation. In contrast, gene induction and repression are strongly associated with changes in patterns of transcription factor occupancy. Our results indicate that during erythroid differentiation, the broad features of chromatin states are established at the stage of lineage commitment, largely independently of GATA1. These determine permissiveness for expression, with subsequent induction or repression mediated by distinctive combinations of transcription factors.
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Affiliation(s)
- Weisheng Wu
- Center for Comparative Genomics and Bioinformatics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Cheng Y, Wu W, Ashok Kumar S, Yu D, Deng W, Tripic T, King DC, Chen KB, Zhang Y, Drautz D, Giardine B, Schuster SC, Miller W, Chiaromonte F, Zhang Y, Blobel GA, Weiss MJ, Hardison RC. Erythroid GATA1 function revealed by genome-wide analysis of transcription factor occupancy, histone modifications, and mRNA expression. Genome Res 2009; 19:2172-84. [PMID: 19887574 PMCID: PMC2792182 DOI: 10.1101/gr.098921.109] [Citation(s) in RCA: 170] [Impact Index Per Article: 11.3] [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] [Received: 07/24/2009] [Accepted: 10/05/2009] [Indexed: 11/24/2022]
Abstract
The transcription factor GATA1 regulates an extensive program of gene activation and repression during erythroid development. However, the associated mechanisms, including the contributions of distal versus proximal cis-regulatory modules, co-occupancy with other transcription factors, and the effects of histone modifications, are poorly understood. We studied these problems genome-wide in a Gata1 knockout erythroblast cell line that undergoes GATA1-dependent terminal maturation, identifying 2616 GATA1-responsive genes and 15,360 GATA1-occupied DNA segments after restoration of GATA1. Virtually all occupied DNA segments have high levels of H3K4 monomethylation and low levels of H3K27me3 around the canonical GATA binding motif, regardless of whether the nearby gene is induced or repressed. Induced genes tend to be bound by GATA1 close to the transcription start site (most frequently in the first intron), have multiple GATA1-occupied segments that are also bound by TAL1, and show evolutionary constraint on the GATA1-binding site motif. In contrast, repressed genes are further away from GATA1-occupied segments, and a subset shows reduced TAL1 occupancy and increased H3K27me3 at the transcription start site. Our data expand the repertoire of GATA1 action in erythropoiesis by defining a new cohort of target genes and determining the spatial distribution of cis-regulatory modules throughout the genome. In addition, we begin to establish functional criteria and mechanisms that distinguish GATA1 activation from repression at specific target genes. More broadly, these studies illustrate how a "master regulator" transcription factor coordinates tissue differentiation through a panoply of DNA and protein interactions.
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Affiliation(s)
- Yong Cheng
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Weisheng Wu
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Swathi Ashok Kumar
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Duonan Yu
- Division of Hematology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
| | - Wulan Deng
- Division of Hematology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
| | - Tamara Tripic
- Division of Hematology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
| | - David C. King
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Kuan-Bei Chen
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Computer Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Ying Zhang
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Daniela Drautz
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Belinda Giardine
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Stephan C. Schuster
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Webb Miller
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Computer Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Francesca Chiaromonte
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Statistics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Yu Zhang
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Statistics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Gerd A. Blobel
- Division of Hematology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
| | - Mitchell J. Weiss
- Division of Hematology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
| | - Ross C. Hardison
- Center for Comparative Genomics and Bioinformatics of the Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Maind SD, Kumar SA, Chattopadhyay N, Gandhi C, Sudersanan M. Analysis of Indian blue ballpoint pen inks tagged with rare-earth thenoyltrifluoroacetonates by inductively coupled plasma–mass spectrometry and instrumental neutron activation analysis. Forensic Sci Int 2006; 159:32-42. [PMID: 16084680 DOI: 10.1016/j.forsciint.2005.05.037] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2005] [Revised: 05/06/2005] [Accepted: 05/23/2005] [Indexed: 11/19/2022]
Abstract
Characterization and assessment of inks on sensitive documents for absolute/relative age determination is the challenging forensic problem in spite of practical difficulties. Tagging of ballpoint pen ink with suitable taggant(s) is a unique method to come out with definitive inferences on the detection of forgery in documents written with ballpoint pens. Selection of a proper taggant primarily depends on sensitivity of analytical determination and their absence in normal varieties of ink used for document writing. Rare-earth elements, from all technical considerations can be potential taggant(s) for inks. To ensure more compatibility with ink, 13 rare-earth thenoyltrifluoroacetonate chelates were prepared and characterized. The ballpoint pen inks were tagged with rare-earth thenoyltrifluoroacetonate chelates individually at about 1-100 ppm level depending on sensitivity of element under suitable optimized experimental conditions and instrumental sensitivity. Aliquots of such tagged ink having varying amounts of taggants were analyzed by ICP-MS and INAA. Satisfactory recoveries and a good linear relationship of intensity (signal) against concentrations/amounts were observed. Under the optimized experimental conditions, the detection limits were worked out. This study of tagging metal ions in combination with ICP-MS and NAA as an analytical tool can allow to draw various combination options based on different rare-earth chelates as suitable materials for tagging of ballpoint pen inks for absolute/relative age determination to aid in document related crime examination. The advantages and limitations of proposed analytical techniques are discussed.
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Affiliation(s)
- S D Maind
- Neutron Activation Analysis Unit of Central Forensic Science Laboratory, Hyderabad, Analytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
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Abdelrahman M, Rafi A, Ghacha R, Kumar SA, Karkar A. Recurrent acute renal failure in a patient with minimal change disease. Saudi J Kidney Dis Transpl 2001; 12:530-533. [PMID: 18209398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
We report on a 16-year old female patient with biopsy proved minimal change disease and steroid state. She was subsequentlygiven cyclosporin for varying periods of time with inadequate response. She developed four episodes of acute renal failure in the background of severe nephrotic state, 10 years after the onset of her illness. Three of these episodes could be reversed with albumin infusion and judicious use of diuretics while the fourth necessitated six sessions of ultrafiltration. In none of the episodes of ARF could we find any cause other than the nephrotic state itself.
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Affiliation(s)
- M Abdelrahman
- Department of Nephrology, Dammam Central Hospital, Dammam, Saudi Arabia
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Youmbissi TJ, Al Amir A, Malik QT, Al Joaeb AS, Al Khursany I, Ghacha R, Kumar SA, Rafi A, Al Ahmed F, Abdul Rahman MR, Karkar A. Simplified Surgical Placement of Tenckhoff Catheter under Local Anesthesia: The Dammam Central Hospital Experience. Saudi J Kidney Dis Transpl 2001; 12:175-178. [PMID: 18209370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
Many methods are used for the placement of Tenckhoff catheters. Eighteen consecutive Tenckhoff catheters were placed under local anesthesia through a mini laparotomy with a reduced operating team. There were only three total catheter failures. Complications were infrequent and operating time was less than one hour on average. This simple procedure should be a part of the training program of all junior surgeons and nephrologists.
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Affiliation(s)
- T J Youmbissi
- Department of Nephrology, Dammam Central Hospital, Dammam, Saudi Arabia
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Mall RP, Trivedi DS, Kumar SA, Girdhar BK. Study of low productive value of rapid survey as a means of leprosy case detection in Kanpur urban project. Indian J Lepr 2000; 70 Suppl:33S-38S. [PMID: 10992865] [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: 02/17/2023]
Abstract
A study was undertaken in Kanpur city to identify the reasons for low yield of rapid survey in leprosy case detection and to intervene to overcome the shortcomings. By a random cluster sampling method, 200,000 persons were selected for the study. Rapid survey was undertaken in half the area and in another half similar survey was undertaken after additional inputs. The additional inputs were staff training, IEC activities, changing of the survey timings and addition of a female worker to the survey teams. The proportion of the population enumerated population showed a significant rise (from 58.35% to 72.21%) in the test area with additional inputs. The number and the type of cases detected did not show any difference. Significantly, addition of female workers to the team did not improve the proportion of the female population examined or of female cases detected.
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Affiliation(s)
- R P Mall
- Damien Foundation India Trust, Madras
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Subrahmanyam D, Sarma VM, Venkateswarlu A, Sastry TV, Srinivas AS, Krishna CV, Deevi DS, Kumar SA, Babu MJ, Damodaran NK. Novel C-ring analogues of 20(S)-camptothecin. Part 3: synthesis and their in vitro cytotoxicity of A-, B- and C-ring analogues. Bioorg Med Chem Lett 2000; 10:369-71. [PMID: 10714502 DOI: 10.1016/s0960-894x(00)00005-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Several 5-substituted alkoxy 20(S)-camptothecin analogues having A- and B-ring substituents were prepared via semi-synthesis. Most of these compounds were found to exhibit potent anti-cancer activity based on their in vitro cytotoxicity data obtained against human tumor cell lines.
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Affiliation(s)
- D Subrahmanyam
- Natural Products Division, Dr. Reddy's Research Foundation, Hyderabad, AP, India.
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Subrahmanyam D, Venkateswarlu A, Venkateswara Rao K, Sastry TV, Vandana G, Kumar SA. Novel C-ring analogues of 20(S)-camptothecin-part-2: synthesis and in vitro cytotoxicity of 5-C-substituted 20(S)-camptothecin analogues. Bioorg Med Chem Lett 1999; 9:1633-8. [PMID: 10397491 DOI: 10.1016/s0960-894x(99)00268-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [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: 10/18/2022]
Abstract
A series of 5-C-substituted 20(S)-camptothecin analogues were synthesised and evaluated their in vitro anti-cancer activity. Several of these analogues have showed excellent activity against human tumor cell lines.
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Affiliation(s)
- D Subrahmanyam
- Natural Products Division, Dr. Reddy's Research Foundation, Miyapur, Hyderabad, India
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Kumar SA, Martin BL. Urticaria and angioedema: diagnostic and treatment considerations. J Am Osteopath Assoc 1999; 99:S1-4. [PMID: 10217914] [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: 02/12/2023]
Abstract
Urticaria and angioedema are common--and commonly frustrating--problems for physicians and patients alike. Patients often are in considerable distress with pruritus and uncomfortable lesions. They are frightened about their condition and frustrated when modern medicine cannot pinpoint the cause of the symptoms. Both urticaria and angioedema may be categorized as acute and chronic conditions. The dividing line between acute and chronic forms is relatively arbitrarily set at 6 weeks. A thorough history and physical examination may provide clues to the underlying cause, but in the majority of patients, the cause is rarely identified. One is more likely to discover the cause of acute than of chronic urticaria. A multitude of laboratory tests can be performed, but they often do not provide a diagnosis. It is not appropriate to do a large "screening" battery of laboratory tests. The dermal mast cells and their mediators play a central role in chronic urticaria. Chronic urticaria may have an autoimmune aspect. Recent evidence reveals that 50% of patients with chronic urticaria have a cutaneous autoimmune disorder mediated by autoantibodies to the high-affinity IgE receptor on mast cells. Biopsy may be necessary and may help with treatment.
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Affiliation(s)
- S A Kumar
- University of Texas Health Science Center at San Antonio, USA
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Inamdar N, Kumar SA, Banavali SD, Advani S, Magrath I, Bhatia K. Comparative incidence of the rearrangements of TEL/AML1 and ALL1 genes in pediatric precursor B acute lymphoblastic leukemias in India. Int J Oncol 1998; 13:1319-22. [PMID: 9824651 DOI: 10.3892/ijo.13.6.1319] [Citation(s) in RCA: 6] [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: 11/05/2022] Open
Abstract
The TEL/AML1 translocation, which is specific for pre B-cell leukemias is predictive of a favorable treatment outcome. In contrast, translocations involving the ALL1 locus which are associated with both B and non B leukemias predict a poor outcome. To determine the relative distribution of high and low risk molecular subtypes of ALL in India, we analyzed the relative frequencies of these two translocations. The study included a random selection of 46 newly diagnosed patients of childhood ALL from the Tata Memorial Hospital, Bombay, India. Similar to the frequency observed in other world regions, we found an All1 rearrangement in less than 7% (3/46) of pre B-ALL patients. In contrast to the 25% frequency reported for other regions the low risk molecular subtype characterized by the TEL/AML1 translocation represented a comparatively smaller fraction (4/46) in this study. These results provide a preliminary support for a lower frequency of molecular subgroup of leukemias with a potential for favorable clinical outcome in precursor B-ALL from India.
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Affiliation(s)
- N Inamdar
- Pediatric Oncology Branch, NCI, NIH, Bethesda, MD 20892, USA
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Shanbhogue HG, Nagendra CL, Annapurna MN, Kumar SA, Thutupalli GK. Multilayer antireflection coatings for the visible and near-infrared regions. Appl Opt 1997; 36:6339-6351. [PMID: 18259487 DOI: 10.1364/ao.36.006339] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
With a high-refractive-index mixed-oxide dielectric material of ZrTiO(4) and ZrO(2) [Substance H2 (Sub2) from E. Merck, Darmstadt, Germany], in combination with magnesium flouride (MgF(2)), design optimization and experimental production of low-loss antireflection (AR) coatings are carried out. Design-optimization studies that make use of these materials as constituents of a seven-layer coating system demonstrate that when the useful bandwidth of an AR coating is extended to cover a wider spectral range, the designs are in general found to have increased integrated reflection loss, higher ripple, and increased spectral instability. The experimental studies on Sub2 material show that the films have excellent optical performance over a wider process window, the advantage of which is demonstrated in the production of different AR coatings on a variety of glasses with refractive indices that range from 1.45 to 1.784 and different mechanical, thermal, and chemical properties. The manufacturing process of AR coatings shows a consistency better than 99% with respect to optical properties and durability.
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Abstract
Phorbol esters such as 12-O-tetradecanoylphorbol-13-acetate (TPA) activate protein kinase C and have been previously shown to down-regulate surfactant proteins SP-A and SP-B in H441 adenocarcinoma cells. We used H441 cells and human fetal lung to further study the mechanism of TPA action and to examine physiologic relevance. In H441 cells, TPA (10 nM) treatment for 24 h decreased SP-A mRNA content to approximately 5% of control cells, with half-maximal effect at approximately 0.5 nM, and reduced SP-A gene transcription rate to 28% of control after 8 h exposure. In cells cultured in the presence of dexamethasone, which increases the low basal level of SP-B expression, TPA decreased both SP-B mRNA content (approximately 8% of control) and rate of transcription (7% of control). In cultured human fetal lung explants, TPA decreased SP-A and SP-B protein and mRNA in a time- and dose-dependent fashion, with half-maximal effect on mRNAs at approximately 3 nM and approximately 50% inhibition after 24 h of exposure, and similarly reduced SP-A and SP-B gene transcription (approximately 55% of control at 8-24 h). We conclude that TPA acts primarily at the level of gene transcription to down-regulate both SP-A and SP-B in H441 and fetal lung cells, and we speculate that inflammatory and other agents that act through PKC may modulate expression of the surfactant proteins and alter surfactant function in vivo.
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Affiliation(s)
- B C Planer
- Department of Pediatrics, University of Pennsylvania School of Medicine, Children's Hospital of Philadelphia, USA
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Kumar SA, Nagendra CL, Thutupalli GK. Low-reflection-loss attenuator optical coatings: theory and experiment. Appl Opt 1996; 35:3047-3051. [PMID: 21085457 DOI: 10.1364/ao.35.003047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Following the optical admittance matching approach, we have derived explicit equations to evaluate the refractive index and thickness of the matching dielectric layer deposited on an attenuator layer to obtain zero or near-zero reflection loss at one or more than one wavelength. With these equations a new family of optical coatings that can not only attenuate the input optical radiation to a required level but can also show a very low reflection loss (less than 0.1%) within a specified band is successfully designed and developed. Typical coatings, produced by electron-beam evaporation, have an average reflection loss of less than 1% and transmittance of 0.42 and 0.64 ± 0.02 over visible and near-IR spectral regions, respectively.
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Affiliation(s)
- S A Kumar
- Allergy/Immunology Service, Fitzsimons Army Medical Center, Aurora, Colorado, USA
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Abstract
Uterine atrophy is a conspicuous finding in Nya:NYLAR female mice chronically infected with Toxoplasma gondii. Administration of 17B-estradiol to infected mice induced a vigorous uterotropic response, i.e., an increase in uterine weight, in endometrial hypertrophy and proliferation, and in the activity of three estrogen-regulated uterine enzymes. These findings rule out a parasite-induced refractoriness of the uterus to estrogen and point to ovarian dysfunction (hypogonadism) as the immediate cause of the uterine atrophy.
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Affiliation(s)
- W Stahl
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201, USA
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Kumar SA, Agarwal GS. Intensity-intensity correlations for the micromaser: Spectral and antibunching characteristics. Phys Rev A 1994; 50:680-684. [PMID: 9910938 DOI: 10.1103/physreva.50.680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Agarwal GS, Kumar SA. Exact quantum-statistical dynamics of an oscillator with time-dependent frequency and generation of nonclassical states. Phys Rev Lett 1991; 67:3665-3668. [PMID: 10044794 DOI: 10.1103/physrevlett.67.3665] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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24
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Abstract
Creatine kinase-B (CKB) synthesis is rapidly and specifically induced by estrogen in the uterus of the immature rat. This study indicates that this elevation is due at least in part to increases in the levels of mRNA for CKB. The stimulation of CKB mRNA levels is rapid (a 7- to 10-fold increase is detected 1-3 h after estrogen administration), but transient, as levels return to near control values by 6 h. Analysis of cDNAs to both uterine and brain CKB mRNA indicate that the same sequence is expressed in both tissues despite earlier observations of heterogeneity of the protein isolated from the two tissues. A 1.7-kilobasepair DNA fragment containing the CKB promoter and 5' flanking sequences confers estrogen sensitivity on expression of the bacterial chloramphenicol acetyl transferase gene in HeLa cells on cotransfection with an estrogen-receptor expression vector. However, the CKB promoter sequences lack any motif with convincing similarity to the currently accepted consensus estrogen response element GGTCAnnnTGACC.
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Affiliation(s)
- B T Pentecost
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201-0509
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Abstract
The human breast cancer cell line MCF-7 produces a number of estrogen-regulated proteins, among which is tissue plasminogen activator (tPA). Increased medium concentrations of PA activity were observed after the addition of 17 beta-estradiol to cultures of MCF-7 cells. However, in the current study these hormone-regulated increases are limited to cultures near or at confluence, but not in the preconfluent period. MCF-7 cell cultures produce either tPA activity alone or in combination with urokinase activators. At confluence, a single exposure to 17 beta-estradiol stimulates a marked transitory rise in tPA activity in the extracellular and cell-associated compartments; the peak increases were at 48 h for medium activity and 24-48 h for cell-associated activity. Sustained exposure to hormone leads to a persistent increase in activity in both compartments. Examination of the structure-function relationships of estrogen agonists, steroidal and nonsteroidal, as well as nonestrogenic steroids indicated that stimulation of PA activity was restricted to estrogen agonists. The increased activity was reflected in enhancement of tissue PA activity when viewed using sodium dodecyl sulfate-polyacrylamide gel zymography. Those cultures expressing both activators revealed no alteration of urokinase activity due to hormone addition. Antiestrogens added to MCF-7 cells not rigorously limited in exogenous estrogens selectively suppressed tissue PA activity, but not that of urokinase. These data indicate that at the point when MCF-7 cell cultures are no longer growing exponentially, addition of estrogen agonists at physiological concentrations elevates tPA activity while not altering expression of urokinase activity. The discussion suggests a possible role that this regulation may subserve in the function of breast epithelial cells.
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Affiliation(s)
- H W Dickerman
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201
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Gierthy JF, Lincoln DW, Gillespie MB, Seeger JI, Martinez HL, Dickerman HW, Kumar SA. Suppression of estrogen-regulated extracellular tissue plasminogen activator activity of MCF-7 cells by 2,3,7,8-tetrachlorodibenzo-p-dioxin. Cancer Res 1987; 47:6198-203. [PMID: 3119194] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) suppresses the estrogen enhancement of tissue plasminogen activator (t-PA) by MCF-7 breast cancer cells. 17 beta-estradiol treatment of MCF-7 cells was previously shown to enhance t-PA secretion in a receptor-mediated process dependent on RNA and protein synthesis. The current studies demonstrate that treatment with TCDD, at a concentration as low as 10(-11) M, reduces the 17 beta-estradiol-induced enhancement of t-PA secretion in these cells. Treatment of MCF-7 cells with TCDD alone does not alter t-PA activity nor was inhibition of t-PA activity observed when TCDD was added directly to the enzyme assay. Kinetic studies and the lack of inhibition following in vitro mixing of conditioned media from TCDD-treated and control 17 beta-estradiol stimulated MCF-7 cells argue against TCDD induction of a plasminogen activator inhibitor. The related polychlorinated dibenzofuran, 2,3,7,8,-tetrachlorodibenzofuran, while also active, is less potent that TCDD. Other polychlorinated dibenzodioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls do not suppress 17 beta-estradiol induction of t-PA over the concentrations tested. These results are in agreement with the structure-activity relationships established using these compounds in other assay systems. Treatment with TCDD does not alter the number or affinity of 17 beta-estradiol receptors of MCF-7 cells. TCDD treatment does not suppress constitutive t-PA activity in the estrogen independent breast cancer line MDA-MB-231 nor the t-PA induced by 12-O-tetradecanoylphorbol-13-acetate in HeLa cells. These effects suggest that TCDD is not acting directly on expression of the t-PA genome. Induction of aryl hydrocarbon hydroxylase by TCDD, a cytochrome P-450 regulated metabolic enzyme for which TCDD is the most potent known inducer, was observed in MCF-7 cells but not in MDA-MB-231 or HeLa cells. A plausible mechanism for the antiestrogenic activity of TCDD is based on the metabolic conversion of 17 beta-estradiol to less active derivatives by TCDD induced cytochrome P-450 metabolic enzymes.
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Affiliation(s)
- J F Gierthy
- Wadsworth Center for Laboratories and Research of the New York State Department of Health, Albany
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Kumar SA, Vasil'ev RK, Rud'ko VF. [Comparative evaluation of suture materials for the closure of facial wounds]. Stomatologiia (Mosk) 1986; 65:44-6. [PMID: 3459278] [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: 01/05/2023]
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Seeger JI, Kumar SA. Induction of creatine kinase in immature rat uteri by zearalenone, an estrogenic mycotoxin. Biochem Int 1985; 10:597-602. [PMID: 3161514] [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: 01/04/2023]
Abstract
Intraperitoneal administration of alpha-zearalenone (ZEN) to female immature rats induced synthesis of a uterine protein which has been identified as creatine kinase. The induced enzyme was purified to homogeneity by chromatography on DEAE Sephacel and Hydroxyapatite Ultrogel. Guinea pig antiserum against estrogen-induced uterine, rat uterine creatine kinase crossreacted with the ZEN-induced enzyme, indicating that ZEN exhibits an early estrogenic response in a manner analogous to natural estrogens.
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Abstract
Monoclonal antibodies were generated against rat uterine estrogen-induced protein--creatine kinase (CK-EIP)--and two (MAb-28 and MAb-78) were studied. These antibodies were IgM but differed in their complementary antigenic determinants both of which were detectable on denatured but not on native CK-EIP. MAb-28 reacted with other CK-BBs but not with CK-MMs whereas MAb-78 reacted with both types of CKs. A measurement of antigenicity with the monoclonal antibodies under calibrated conditions showed differences among the CKs, notably between CK-BB from rat brain and CK-EIP when both were probed with MAb-28. The antigenicity of CK-BB (rat brain) was significantly lower than that of CK-EIP, indicating that the former either expresses less copies of the determinant recognized by MAb-28 than CK-EIP does, or possesses a determinant which interacts with the antibody with lower affinity. The monoclonal antibodies should help elucidate structure-function relationships in CK-BB and CK-EIP molecules, their anatomic distribution and their physiologic, pathologic and experimental variations in relation to gene expression induced by sex hormones.
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Ryan TJ, Seeger JI, Kumar SA, Dickerman HW. Estradiol preferentially enhances extracellular tissue plasminogen activators of MCF-7 breast cancer cells. J Biol Chem 1984; 259:14324-7. [PMID: 6542103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
Abstract
MCF-7 human breast cancer cells secrete two immunologic types of plasminogen activator, one related to urokinase, the other unrelated. We have now examined whether estrogen stimulation of secreted plasminogen activator activity reflects an increase in one or both types. Examined semiquantitatively by sodium dodecyl sulfate-polyacrylamide gel electrophoretic zymography, the conditioned media of control cells were seen to contain a major activator band (Mr approximately 54,000) immunologically related to urokinase and a barely discernible doublet (Mr approximately 64,000 and Mr approximately 68,000). Addition of estradiol or, at much higher concentrations, testosterone led to marked enhancement of doublet activity, while the 54-kDa band was invariant. The 64-68-kDa doublet was immunoreactive with antiserum directed against Bowes melanoma tissue plasminogen activator but not with antiurokinase antibodies. Enhancement of doublet activity was correlated with hormone-induced increases in total secreted plasminogen activator activity. Neither progesterone nor dexamethasone increased total activity or the 64-68-kDa zones of lysis. Estradiol and testosterone alterations were blocked by appropriate concentrations of an estrogen antagonist (LY156758), actinomycin D, or cycloheximide. Regulation of MCF-7 cell-secreted tissue plasminogen activators thus appears to be mediated by an estrogen receptor process and to require sustained RNA and protein synthesis.
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Ryan TJ, Seeger JI, Kumar SA, Dickerman HW. Estradiol preferentially enhances extracellular tissue plasminogen activators of MCF-7 breast cancer cells. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)42595-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Yourno J, Walsh J, Kornatowski G, O'Connor D, Kumar SA. Nonspecific esterases of leukemia cell lines: evidence for activation of myeloid-associated zymogens in HL-60 by phorbol esters. Blood 1984; 63:238-41. [PMID: 6580927] [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: 01/20/2023] Open
Abstract
Myeloid leukemia cell line HL-60 contains fluoride-sensitive, myeloid-associated isoenzymes of nonspecific esterase that increase in activity when cultures are treated with phorbol ester. These isoenzymes are not detectable in B-lymphoblast cell line KLM-2, either in control or in phorbol-ester-treated cultures. No increased de novo synthesis of the isoenzymes is detectable in HL-60 treated with phorbol ester. The data suggest stimulated conversion of a preformed, myeloid-associated zymogen in HL-60.
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Abouna GM, Al-Adnani MS, Kremer GD, Kumar SA, Daddah SK, Kusma G. Reversal of diabetic nephropathy in human cadaveric kidneys after transplantation into non-diabetic recipients. Lancet 1983; 2:1274-6. [PMID: 6139620 DOI: 10.1016/s0140-6736(83)91151-0] [Citation(s) in RCA: 128] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Two kidneys were removed from a cadaveric donor with 17-year history of type 1 diabetes. At the time of death the donor had proteinuria but normal serum creatinine, and on histological examination the kidneys showed features of established diabetic nephropathy including diffuse glomerulosclerosis and thickening of mesangial matrix and capillary basement membranes. After transplantation into non-diabetic recipients (cold ischaemia times 46 h and 52 h) the kidneys functioned well with standard immunosuppression. Renal biopsy specimens taken 7 months after transplantation showed almost complete resolution of the nephropathy and both patients remain free from proteinuria after a further 7 months. As well as indicating that longstanding type 1 diabetes need not always contraindicate kidney donation, these observations are relevant to the pathogenesis and management of diabetic nephropathy.
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O'Connor DL, Kumar SA. Inhibition of DNA-dependent RNA polymerase from Escherichia coli by pyran copolymer. Biochem Int 1983; 6:489-96. [PMID: 6385976] [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: 01/19/2023]
Abstract
Pyran copolymer, a potent inhibitor of DNA-dependent RNA polymerase from Escherichia coli, prevented polyribonucleotide synthesis by blocking both the initiation and elongation steps. The inhibition was noncompetitive with respect to template and nucleotide triphosphate substrates. Template binding and the stability of the nascent RNA chain were not affected by the inhibitor.
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Abstract
Currently available diagnostic techniques for myocardial contusion following blunt chest trauma were evaluated. We investigated 30 patients prospectively over a period of 1 year for the presence of myocardial contusion. Among the 30 patients, eight were found to have myocardial contusion on the basis of abnormal electrocardiograms, elevated creatine phosphokinase MB fraction (CPK-MB), and positive myocardial scan. Myocardial scan was positive in seven of eight patients (87.5%). CPK-MB fraction was elevated in four of eight patients (50%). Definitive electrocardiographic changes were seen in only two of eight patients (25%). It appears that myocardial scan using technetium pyrophosphate and CPK-MB fraction determinations are the most reliable aids in diagnosis of myocardial contusion following blunt chest trauma.
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Kumar SA, O'Connor DL, Seeger JI, Beach TA, Dickerman HW. Purification and characterization of creatine kinase, an estrogen-induced uterine protein (IP) from immature rats. Biochem Biophys Res Commun 1983; 111:156-65. [PMID: 6830587 DOI: 10.1016/s0006-291x(83)80130-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
An estrogen-responsive translational product, the induced protein (IP) first described by Notides and Gorski (8), was obtained solely from the target organ, immature rat uterus, and purified to homogeneity in a procedure using two chromatography steps. The purified IP has a molecular weight of 49,000, and the isoelectric point is 5.2. Creatine kinase activity is associated with the homogeneous IP. There are some differences between the uterine enzyme and the creatine kinase BB isoenzyme, including differences in stability, and sensitivity to mercaptans. Estrogen-induced creatine kinase purified by this simple, reproducible method is a useful antigen for further studies on the translation and transcription processes involved in hormone-modulated synthesis.
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Abstract
Oligodeoxynucleotides covalently linked to cellulose were used as probes of the DNA-binding domains of mouse steroid holoreceptors. With uterine cytosol estrogen receptor (E2R) the relative binding order, in prior studies, was oligo(dG) greater than oligo(dT) greater than or equal to oligo(dC) much greater than oligo(dA) greater than oligo(dI). The binding reactions were salt-sensitive with an optimal KCl concentration of 0.1-0.2 M. There was no enhancement of binding by activation, either temperature- or salt-induced. In the present study, using the oligomer ligands at a lower concentration, oligo(dT) binding was greater than that to oligo(dC). Quantitative differences in oligodeoxynucleotide binding were elicited by a number of inhibitors. These differences are again seen by exposure of E2R to chaotropic salts such as SCN-, ClO-4 and NO3- as well as to putative modifiers of receptor amino acids, ie, iodoacetamide, 1,2 cyclohexanedione, and Rose Bengal. These results, and the quantitative differences following heat and purification, led to a designation of two types of subsites within the DNA-binding domain of uterine E2R. These are stable G sites, which interact with oligo(dG); and labile N sites, which bind to oligo(dT), oligo(dC) and oligo(dA). Stimulation of binding to N sites and stabilization of the holoreceptor was effected by histones H2A and H2B. However, the differential response to incubation at 37 degrees C was not altered by addition of H2B. Treatment of uterine E2R by limited proteolysis also eliminated the stimulatory response to H2B. The above data, as well as prior studies, indicate that steroid holoreceptors can discriminate between the structural features of deoxynucleotide bases and this recognition process can be modulated by accessory proteins.
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Gross SC, Kumar SA, Dickerman HW. Immobilized oligodeoxynucleotides as probes of the DNA-binding sites of mouse steroid holoreceptors. J Biol Chem 1982; 257:4738-45. [PMID: 6896051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Steroid hormone receptors are DNA-binding proteins with distinct domains for the steroid ligand and for polydeoxyribonucleotides. The characteristics of the polynucleotide-binding sites of the mouse liver dexamethasone receptor, kidney testosterone and estradiol receptors, and uterine estradiol receptor were examined by using oligodeoxynucleotides covalently linked to cellulose as probes. Only dexamethasone receptor binding to oligodeoxynucleotides was dependent upon activation by increased salt concentrations or temperature. The dexamethasone and estradiol receptors required a distinct concentration of KCl for maximal binding to oligodeoxynucleotide-cellulose. In contrast, binding of mouse kidney testosterone receptor was not stimulated by KCl although it was decreased at 0.2 M KCl. The nucleotide affinities of the mouse receptors generally followed the order of binding to oligo(dG)- greater than oligo(dT)- greater than oligo(dC)- greater than oligo(dA)-cellulose. However, the liver dexamethasone receptor bound to oligo(dT)- more avidly than to oligo(dC)-cellulose, while neither the testosterone nor the estradiol receptors clearly differentiated between the oligodeoxypyrimidine celluloses. Although the binding of the kidney testosterone receptor was poorest of those studied, it bound to oligo(dA)-cellulose relatively more efficiently than did the other steroid receptors. Thus, differences were revealed in the requirements for activation, added salt for binding, and relative binding efficiencies to the ligands among different steroid receptors from the same tissue and among the same steroid receptors from different tissues.
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Abstract
As a model for interaction of steroid receptors with DNA, the binding of estradiol receptor complexes (E2R) to oligodeoxynucleotides, covalently linked to cellulose, was studied in detail. Binding was optimal at concentrations of monovalent cationic salts at, or near, isotonic levels and was selective for intracellular receptors in contrast to extracellular steroid binding proteins. Among the oligomers, the order of affinity was oligo dG greater than oligo dT greater than oligo dC greater than oligo dA greater than oligo dI. The binding to oligo dG was stable to 37 degrees C exposure and the processes of adsorption and desorption, while reactivity with oligo dT, oligo dC and oligo dA was labile. The decrease in binding following purification was restored by histone 2B. Oligo dG binding was the most resistant to inhibition by cibacron blue F3GA (CB) and pyridoxal-5-phosphate. On the basis of these data, a hypothesis is proposed for the interaction of mouse uterine cytosol E2R with prevalent nonspecific and putative specific sequences of DNA.
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Abstract
Exposure of calf uterine estradiol-receptor complexes to diethylpyrocarbonate (ethoxyformic anhydride) at pH 6.3-6.5 results in a decrease in the ability of the receptor to bind to oligodeoxyribonucleotides. The inhibition of binding to oligodeoxypyrimidines is greater than the inhibition of binding to oligodeoxyguanylate. The inhibition by 6.6 mM diethylpyrocarbonate is complete within 10 min at 4 degrees C. Addition of equimolar quantities of histidine or imidazole prior to exposure to diethylpyrocarbonate prevents subsequent inhibition of oligodeoxyribonucleotide binding. In comparison to histidine, other amino acids tested were deficient in this ability. Diethylpyrocarbonate modification of the receptor causes complete loss of oligodeoxyribonucleotide binding activity at times when there is a loss of less than 20% of bound steroid. Pyridoxal 5'-phosphate treatment of receptor does not prevent subsequent modification by diethylpyrocarbonate, suggesting that the site of reaction is not an essential lysine of the DNA-binding domain. Treatment of the ethoxyformylated receptor with 0.45 M hydroxylamine results in recovery of 70% of the receptor's oligonucleotide-binding ability. The time course of the reaction of diethylpyrocarbonate with the estradiol receptor and the demonstration of hydroxylamine reversal of inhibition suggest that histidine is involved in the binding of estradiol receptor to oligodeoxyribonucleotides.
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Kumar SA, Beach TA, Dickerman HW. Specificity of oligodeoxynucleotide binding of mouse uterine cytosol estradiol receptors. Proc Natl Acad Sci U S A 1980; 77:3341-5. [PMID: 6932023 PMCID: PMC349611 DOI: 10.1073/pnas.77.6.3341] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The relative capacities of oligodeoxynucleotides, covalently linked to cellulose, to bind estradiol receptor complexes (E2R) of mouse uterine cytosol have been shown to follow the order oligo(dG) > oligo(dT) greater than or equal to oligo(dC) > oligo(dA). The E2R . oligo(dT)-cellulose-binding reaction is more sensitive to Cibacron blue F3GA than is E2R . oligo(dG)-cellulose or oligo(dC)-cellulose binding. Preformed E2R . oligo(dT)- or oligo(dC)-cellulose complexes are dissociated more readily by lower concentrations of KCl or Cibacron blue F3GA than is the E2R . oligo(dG)-cellulose complex. Preincubation of E2R at 37 degrees C results in a rapid loss of binding ability towards oligo(dT)- and oligo(dC)-cellulose, while up to 90% of the binding ability to oligo(dG)-cellulose is retained. On the basis of the differential sensitivities of E2R to temperature and the inhibition by Cibacron blue F3GA of the binding reaction, it is suggested that the polynucleotide-binding domain consists of two types of subsites, one of which has a higher affinity for oligo(dG) residues and the other of which recognizes oligo(dT), oligo(dC), and, to a lesser extent, oligo(dA).
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Kumar SA, Beach TA, Dickerman HW. Effect of Cibacron blue F3GA on oligonucleotide binding site of estradiol--receptor complexes of mouse uterine cytosol. Proc Natl Acad Sci U S A 1979; 76:2199-203. [PMID: 287059 PMCID: PMC383565 DOI: 10.1073/pnas.76.5.2199] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The binding of estradiol--receptor complexes of mouse uterine cytosol to oligodeoxynucleotide celluloses is inhibited by the sulfonated polyaromatic dye Cibacron blue F3GA. The dye does not have any effect on the estradiol binding site. Additon of the dye to preformed estradiol--receptor--oligo(dT)-cellulose complex results in the release of estradiol--receptor. The inhibition of binding is competitive with respect to oligo(dT)- or oligo(dA)-Celluloses, suggesting that the effect of the dye is directly on the polynucleotide binding site of the receptor. The observed inhibitory effect of Cibacron blue is not a simple electrostatic effect of polyanions because heparin and polyglutamic acid are much less effective. The selective inhibition by Cibacron blue suggests that the polynucleotide binding domain of estradiol--receptor possesses a special "supersecondary" structure [Stellwagen, E. (1977) Acc. Chem. Res. 10, 92--98].
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Kumar SA, Beach T, Dickerman HW. Effect of chaotropic anions on the rate of dissociation of estradiol-receptor protein complexes of mouse uterine cytosol. Biochem Biophys Res Commun 1978; 84:631-8. [PMID: 718706 DOI: 10.1016/0006-291x(78)90752-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Kumar SA, Krakow JS. Inhibition of Azotobacter vinelandii RNA polymerase by cibacron blue F3GA. J Biol Chem 1977; 252:5724-8. [PMID: 885877] [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: 12/24/2022] Open
Abstract
Cibacron blue F3GA is a potent inhibitor of the Azotobacter vinelandii DNA-directed RNA polymerase. Addition of 8 micrometer Cibacron blue F3GA prior to initiation results in a greater than 90% inhibition of the poly[d(A-T]-directed synthesis of poly[r(A-U)] while addition of the dye during the course of the reaction is without effect on chain elongation. Binding of RNA polymerase to [3H]poly[d(A-T)] is inhibited by only 15% in the presence of 8 micrometer Cibacron blue F3GA. Inhibition by Cibacron blue F3GA is noncompetitive with regard to ATP, UTP, or template. The poly[d(A-T)]-directed pyrophosphate exchange reaction is relatively resistant to inhibition by Cibacron blue F3GA. Rifampicin added to a similar reaction (in the presence of absence of Cibacron blue F3GA) results in 95% inhibition of the exchange reaction. The interaction of the RNA polymerase core enzyme with Cibacron blue F3GA is shown by the formation of a difference spectrum with a positive maximum at 675 nm which is not affected by the presence of a high concentration (4 micrometer) of rafampicin. The data indicate that Cibacron blue F3GA acts by binding to RNA polymerase and inhibits a step between the synthesis of the initial phosphodiester bond and formation of a stable ternary elongation complex.
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Kumar SA, Krakow JS, Ward DC. ATP analogues as initiation and elongation nucleotides for bacterial DNA-dependent RNA polymerase. Biochim Biophys Acta 1977; 477:112-24. [PMID: 328048 DOI: 10.1016/0005-2787(77)90227-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Kalyanaraman VS, Mahadevan S, Kumar SA. Oxidase-peroxidase enzymes of Datura innoxia. Oxidation of formylphenylacetic acid ethyl ester. Biochem J 1975; 149:565-76. [PMID: 997 PMCID: PMC1165663 DOI: 10.1042/bj1490565] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
An enzyme system from Datura innoxia roots oxidizing formylphenylacetic acid ethyl ester was purified 38-fold by conventional methods such as (NH4)2SO4 fractionation, negative adsorption on alumina Cy gel and chromatography on DEAE-cellulose. The purified enzyme was shown to catalyse the stoicheiometric oxidation of formylphenylacetic acid ethyl ester to benzoylformic acid ethyl ester and formic acid, utilizing molecular O2. Substrate analogues such as phenylacetaldehyde and phenylpyruvate were oxidized at a very low rate, and formylphenylacetonitrile was an inhilating agents, cyanide, thiol compounds and ascorbic acid. This enzyme was identical with an oxidase-peroxidase isoenzyme. Another oxidase-peroxidase isoenzyme which separated on DEAE-chromatography also showed formylphenylacetic acid ethyl ester oxidase activity, albeit to a lesser extent. The properties of the two isoenzymes of the oxidase were compared and shown to differ in their oxidation and peroxidation properties. The oxidation of formylphenylacetic acid ethyl ester was also catalysed by horseradish peroxidase. The Datura isoenzymes exhibited typical haemoprotein spectra. The oxidation of formylphenylacetic acid ethyl ester was different from other peroxidase-catalysed reactions in not being activated by either Mn2+ or monophenols. The oxidation was inhibited by several mono- and poly-phenols and by catalase. A reaction mechanism for the oxidation is proposed.
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Kalyanaraman VS, Kumar SA, Mahadevan S. Oxidase-peroxidase enzymes of Datura innoxia. Oxidation of reduced nicotinamide-adenine dinucleotide in the presence of formylphenylacetic acid ethyl ester. Biochem J 1975; 149:577-84. [PMID: 173292 PMCID: PMC1165664 DOI: 10.1042/bj1490577] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The oxidase-peroxidase from Datura innoxia which catalyses the oxidation of formylphenylacetic acid ethyl ester to benzoylformic acid ethyl ester and formic acid was also found to catalyse the oxidation of NADH in the presence of Mn2+ and formylphenylacetic acid ethyl ester. NADH was not oxidized in the absence of formylphenylacetic acid ethyl ester, although formylphenylacetonitrile or phenylacetaldehyde could replace it in the reaction. The reaction appeared to be complex and for every mol of NADH oxidized 3-4 g-atoms of oxygen were utilized, with a concomitant formation of approx. 0.8 mol of H2O2, the latter being identified by the starch-iodide test and decomposition by catalase. Benzoylformic acid ethyl ester was also formed in the reaction, but in a nonlinear fashion, indicating a lag phase. In the absence of Mn2+, NADH oxidation was not only very low, but itself inhibited the formation of benzoylformic acid ethyl ester from formylphenylacetic acid ethyl ester. A reaction mechanism for the oxidation of NADH in the presence of formylphenylacetic acid ethyl ester is proposed.
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Kumar SA, Krakow JS. Studies on the product binding sites of the Azotobacter vinelandii ribonucleic acid polymerase. J Biol Chem 1975; 250:2878-84. [PMID: 1123330] [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: 12/25/2022] Open
Abstract
During chain elongation RNA polymerase exists as a ternary DNA-enzyme-RNA complex in which a discrete length of the nascent RNA chain proximal to the 3'-OH terminus will be bound to the product binding site (Krakow, J. S., and Fronk, E. (1969) J. Biol. Chem. 244, 5988). We have utilized the poly[d(A-T)]-directed reaction to determine the length of the nascent poly[r(A-U)] protected from attack by pancreatic ribonuclease. Following release of the ribonuclease resistant oligo[r(A-U)] from the ternary complex, its size was determined by ion exchange chromatography on DEAE-cellulose, gel filtration on Bio-Gel P-10, and the ratio of 3'-terminal uridine to internal 2':3'-UMP following alkaline hydrolysis. The results indicate that the length of the nascent protected fragment is approximately 12 residues.
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