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Soundravally R, Sankar P, Bobby Z, Hoti SL. Oxidative stress in severe dengue viral infection: association of thrombocytopenia with lipid peroxidation. Platelets 2009; 19:447-54. [PMID: 18925513 DOI: 10.1080/09537100802155284] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Oxidative stress in viral infections has been suggested. The study was carried out to assess the oxidative stress in the different clinical spectrums of dengue infection and to evaluate if thrombocytopenia is associated with lipid and protein oxidative injury. Twenty-seven dengue fever (DF), 32 dengue hemorrhagic fever (DHF) and 21 dengue shock syndrome (DSS) cases were studied at 3, 5 and 7 days of illness. Sixty-three healthy subjects were selected as controls. Serum protein carbonyls (PCOs), malendialdehyde (MDA) and total antioxidant status (TAS) were estimated in blood. Dengue infected individuals had significantly high levels of PCOs and MDA on the three days tested in comparison to controls. In DF cases, no significant changes in the levels of MDA and PCOs were found in course of time. However, among DHF and DSS, significant increase in MDA levels was found in the fifth and seventh day samples in comparison to their respective third day sample (P < 0.05). Using one way ANOVA, high PCOs levels were found in DSS in comparison to DF and DHF cases on all the three days tested (P < 0.001). TAS levels were found to be low among DSS on days 5 and 7 and day 7 in DHF when compared with DF cases. Correlation analysis between MDA and hematocrit revealed a significant positive association between them in DHF and DSS on day 5 (DHF r = 0.372; p = 0.024 and DSS r = 0.535; p = 0.0-01) and day 7 (DHF r = 0.412; p = 0.003 and DSS r = 0.765; p < 0.0001). There was an important negative correlation between platelet count and plasma lipid peroxidation levels among DHF and DSS on all three days tested [day 3 (DHF r = -0.392; p = 0.012 and DSS r = -0.453; p = 0.004), day 5 (DHF r = -0.592; p < 0.001 and DSS r = -0.581; p < 0.001) and day 7 (DHF r = -0.418; p = 0.001 and DSS r = -0.515; p = 0.002)]. This study concludes that an increase in oxidative stress was found in dengue viral infection. The level of oxidative stress was maximal in DSS followed by DHF and its severity was minimal in DF. The thrombocytopenia of dengue infection was associated with the extent of lipid peroxidation. Future studies might be carried out to find the role of oxidative damage in the ethiopathogenesis of thrombocytopenia and vascular leakage in dengue infection.
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Jenkins G, Merz JF, Sankar P. A qualitative study of women's views on medical confidentiality. JOURNAL OF MEDICAL ETHICS 2005; 31:499-504. [PMID: 16131550 PMCID: PMC1734225 DOI: 10.1136/jme.2004.010280] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
CONTEXT The need to reinvigorate medical confidentiality protections is recognised as an important objective in building patient trust necessary for successful health outcomes. Little is known about patient understanding and expectations from medical confidentiality. OBJECTIVE To identify and describe patient views of medical confidentiality and to assess provisionally the range of these views. DESIGN Qualitative study using indepth, open ended face-to-face interviews. SETTING Southeastern Pennsylvania and southern New Jersey, USA. PARTICIPANTS A total of 85 women interviewed at two clinical sites and three community/research centres. MAIN OUTCOME MEASURES Subjects' understanding of medical confidentiality, beliefs about the handling of confidential information and concerns influencing disclosure of information to doctors. RESULTS The subjects defined medical confidentiality as the expectation that something done or said would be kept "private" but differed on what information was confidential and the basis and methods for protecting information. Some considered all medical information as confidential and thought confidentiality protections functioned to limit its circulation to medical uses and reimbursement needs. Others defined only sensitive or potentially stigmatising information as confidential. Many of these also defined medical confidentiality as a strict limit prohibiting information release, although some noted that specific permission or urgent need could override this limit. CONCLUSIONS Patients share a basic understanding of confidentiality as protection of information, but some might have expectations that are likely not met by current practice nor anticipated by doctors. Doctors should recognise that patients might have their own medical confidentiality models. They should address divergences from current practice and provide support to those who face emotional or practical obstacles to self-revelation.
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Casarett D, Karlawish J, Sankar P, Hirschman K, Asch DA. Designing pain research from the patient's perspective: what trial end points are important to patients with chronic pain? PAIN MEDICINE 2005; 2:309-16. [PMID: 15102235 DOI: 10.1046/j.1526-4637.2001.01041.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVES The goals of this study were to define the endpoints of pain research that are important to patients with chronic pain and to identify clinical and demographic variables that are associated with patients' choices of endpoints. PATIENTS & SETTING Interviews were completed with 40 patients seen at the anesthesia pain clinic of an urban tertiary care medical center. DESIGN Each patient was presented with 4 brief (3-4 sentences) fixed information vignettes describing studies in which new medications would be evaluated. For each, patients were asked to describe how the medication being studied might offer an improvement over their current therapy. OUTCOME MEASURES Measures included structured qualitative analysis of responses, the Brief Pain Inventory, and Global Distress Index of the Memorial Symptom Assessment Scale. RESULTS Patients described a total of 20 endpoints. Individually, patients cited between 2 and 9 endpoints each (mean 4.9, standard deviation 1.7). Of these, the most commonly cited were decrease pain, decrease opioid dose, decrease frequency of scheduled dose, increased ability to function, decrease frequency of breakthrough dose, and improve sleep. Patients with severe pain cited more endpoints than did those with mild or moderate pain (mean 5.5 vs. 4.3; Rank sum test p = 0.01). CONCLUSIONS These data suggest that empirical research can provide data to guide the choice of endpoints in clinical studies of pain interventions.
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Merz J, McGee G, Sankar P. Response from Jon F. Merz, Glenn E. McGee, and Pamela Sankar to Hoeyer and Lynöe's commentary on their article “‘Iceland Inc.’? On the Ethics of Commercial Genomics”. Soc Sci Med 2004. [DOI: 10.1016/j.socscimed.2003.09.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Hornik R, Sankar P. Reaching mothers in Swaziland: preliminary findings of a child survival program. DEVELOPMENT COMMUNICATION REPORT 2002:7-9. [PMID: 12340545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Parsons GN, Kinsman SB, Bosk CL, Sankar P, Ubel PA. Between two worlds medical student perceptions of humor and slang in the hospital setting. J Gen Intern Med 2001; 16:544-9. [PMID: 11556931 PMCID: PMC1495252 DOI: 10.1046/j.1525-1497.2001.016008544.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Residents frequently use humor and slang at the expense of patients on the clinical wards. We studied how medical students react to and interpret the "appropriateness" of derogatory and cynical humor and slang in a clinical setting. DESIGN Semistructured, in-depth interviews. SETTING Informal meeting spaces. PARTICIPANTS Thirty-three medical students. MEASUREMENTS Qualitative content analysis of interview transcriptions. MAIN RESULTS Students' descriptions of the humorous stories and their responses reveal that students are able to take the perspective of both outsiders and insiders in the medical culture. Students' responses to these stories show that they can identify the outsider's perspective both by seeing themselves in the outsider's role and by identifying with patients. Students can also see the insider's perspective, in that they identify with residents' frustrations and disappointments and therefore try to explain why residents use this kind of humor. Their participation in the humor and slang--often with reservations--further reveals their ability to identify with the perspective of an insider. CONCLUSIONS Medical students describe a number of conflicting reactions to hospital humor that may enhance and exacerbate tensions that are already an inevitable part of training for many students. This phenomenon requires greater attention by medical educators.
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Casarett D, Karlawish J, Sankar P, Hirschman KB, Asch DA. Open label extension studies and the ethical design of clinical trials. IRB 2001; 23:1-5. [PMID: 11837283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
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Casarett D, Karlawish J, Sankar P, Hirschman KB, Asch DA. Obtaining informed consent for clinical pain research: patients' concerns and information needs. Pain 2001; 92:71-9. [PMID: 11323128 DOI: 10.1016/s0304-3959(00)00473-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Investigators who conduct clinical pain research are required to obtain voluntary informed consent from patients. However, little is known about what information patients expect when they decide whether to enroll in such studies. It is important that investigators understand these information needs so they can effectively and clearly describe the research risks and potential benefits that matter to potential subjects. By understanding these needs for information, investigators may also be better able to anticipate patients' concerns and to recruit subjects more efficiently. This study was designed to define information needs that patients have when they decide whether to participate in clinical pain research. This paper describes these information needs, and identifies clinical and demographic variables associated with specific needs.
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Karlawish JH, Casarett D, Klocinski J, Sankar P. How do AD patients and their caregivers decide whether to enroll in a clinical trial? Neurology 2001; 56:789-92. [PMID: 11274319 DOI: 10.1212/wnl.56.6.789] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
To examine how patients and caregivers decide whether to enroll in a clinical trial, the authors conducted semi-structured interviews with 22 family caregivers of patients with mild to moderate AD who were recruited for a clinical trial. They found that a caregiver who enrolls a patient in research generally involves the patient in the decision-making process, reports that the patient shares in the decision, and regards the risks and benefits to the patient and to the caregiver as interdependent.
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Cho MK, Sankar P, Wolpe PR, Godmilow L. Commercialization of BRCA1/2 testing: practitioner awareness and use of a new genetic test. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 83:157-63. [PMID: 10096590 PMCID: PMC2225442 DOI: 10.1002/(sici)1096-8628(19990319)83:3<157::aid-ajmg4>3.0.co;2-g] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
It was our purpose to determine the characteristics of practitioners in the United States who were among the first to inquire about and use the BRCA1 and BRCA2 (BRCA1/2) genetic tests outside of a research protocol. Questionnaires were mailed to all practitioners who requested information on or ordered a BRCA1/2 test from the University of Pennsylvania (UPenn) Genetic Diagnostics Laboratory (GDL) between October 1, 1995 and January 1, 1997 (the first 15 months the test was available for clinical use). The response rate was 67% of practitioners; 54% (121/225) were genetic counselors, 39% (87/225) were physicians or lab directors. Most physicians were oncologists, pathologists, or obstetrician/gynecologists, but 20% practiced surgery or internal or general medicine. Fifty-six percent (125/225) had ordered a BRCA1/2 test for a patient; most of the rest had offered or were willing to offer testing. Of those who had offered testing, 70% had a patient decline BRCA1/2 testing when offered. Practitioners perceived that patients' fear of loss of confidentiality was a major reason for declining. Nearly 60% of practitioners reported that their patients had access to a genetic counselor, but 28% of physicians who ordered a BRCA1/2 test reported having no such access, despite the GDL's counseling requirement. The proportion of physicians reporting no access to genetic counselors for their patients increased from 22.4% in the first half of the study to 50% in the last half. Many practitioners have an interest in BRCA1/2 testing, despite policy statements that discourage its use outside of research protocols. Practitioner responses suggest that patient interest in testing seems to be tempered by knowledge of potential risks. An apparent increase in patient concern about confidentiality and inability to pay for testing could indicate growing barriers to testing. Although most practitioners reported having access to counseling facilities, perceived lack of such access among an increasing proportion of practitioners indicates that lab requirements for counseling are difficult to enforce and suggests that an increasing proportion of patients may not be getting access to counseling.
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Merz JF, Spina BJ, Sankar P. Patient consent for release of sensitive information from their medical records: an exploratory study. BEHAVIORAL SCIENCES & THE LAW 1999; 17:445-454. [PMID: 10653993 DOI: 10.1002/(sici)1099-0798(199910/12)17:4<445::aid-bsl359>3.0.co;2-p] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The disclosure of sensitive information concerning mental health, drug and alcohol use, and communicable diseases requires express patient consent under federal and state laws. This paper presents the results of a retrospective medical record abstraction of hospital consent-to-treatment and release-of-information forms, examining whether the forms are present in the records, and, if so, whether they are signed by patients. The results suggest that patients who have sensitive information in their medical records or pay out of pocket for their care are less likely to consent to disclosure of their records. We discuss the implications of these results and recommend further research to understand patients' perceptions of medical confidentiality and the processes used for securing consent to hospital treatment.
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Merz JF, Sankar P, Yoo SS. Hospital consent for disclosure of medical records. THE JOURNAL OF LAW, MEDICINE & ETHICS : A JOURNAL OF THE AMERICAN SOCIETY OF LAW, MEDICINE & ETHICS 1998; 26:241-179. [PMID: 11066882 DOI: 10.1111/j.1748-720x.1998.tb01425.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Disclosure of information clauses in general consent-to-treatment forms used by 202 large hospitals nationwide are described and mapped into a taxonomy to distinguish types of disclosures and to help structure consent documents.
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Abstract
OBJECTIVES The point system used to distribute scarce transplantable kidneys places great emphasis on antigen matching. This contributes to increased waiting times for African Americans, who have a disproportionate share of rare antigens. We conducted a pilot study to explore the understanding and attitudes of kidney transplant candidates toward the way the transplant allocation system trades off between antigen matching and waiting time. MEASUREMENTS AND MAIN RESULTS We performed semi-structured interviews of a convenience sample of 33 patients awaiting transplants in Philadelphia and its surrounding suburbs. Patients had a number of misconceptions about the transplant allocation system. Many incorrectly thought, for example, that quality of life and financial status influence which patients on the waiting list receive available organs. Despite these and other misconceptions, the majority of patients thought the allocation system was fair. However, many African Americans thought the system was biased against them because of their race. After hearing about how the transplant system factors antigen matching and waiting time into organ allocation, the majority of subjects still felt the system was fair. After hearing that the emphasis on antigen matching causes African Americans to wait twice as long as whites, a larger number of subjects thought the system was unfair. Nevertheless, few thought the system should be changed. Even African American patients who felt the system was unfair still approved of the emphasis on antigen matching out of a desire to have a successful kidney transplant. CONCLUSIONS We found that most of the interviewed patients awaiting kidney transplant thought the system should continue to emphasize antigen matching. Although attitudes toward the allocation system differed by race, with African American patients more suspicious of the system, the importance patients placed on antigen matching did not appear to differ by race.
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Merz JF, Sankar P, Taube SE, Livolsi V. Use of human tissues in research: clarifying clinician and researcher roles and information flows. J Investig Med 1997; 45:252-7. [PMID: 9249997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Kabilan S, Pandiarajan K, Krishnasamy K, Sankar P. Oxidative cleavage of S-arylmercaptoacetic acids by sodium perborate: Kinetic and correlation study. INT J CHEM KINET 1995. [DOI: 10.1002/kin.550270504] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Sankar P, Hutton ME, VanBogelen RA, Clark RL, Neidhardt FC. Expression analysis of cloned chromosomal segments of Escherichia coli. J Bacteriol 1993; 175:5145-52. [PMID: 8349554 PMCID: PMC204981 DOI: 10.1128/jb.175.16.5145-5152.1993] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The novel transcription system of bacteriophage T7 was used to express Escherichia coli genes preferentially with a new low-copy-number plasmid vector, pFN476, to minimize toxic gene effects. Selected E. coli chromosomal fragments from an ordered genomic library (Y. Kohara, K. Ikiyama, and K. Isono, Cell 50:495-508, 1987) were recloned into this vector, and their genes were preferentially expressed in vivo utilizing its T7 promoter. The protein products were analyzed by two-dimensional gel electrophoresis. By using DNA sequence information, the gel migration was predicted for the protein products of open reading frames from these segments, and this information was used to identify gene products visualized as spots on two-dimensional gels. Even in the absence of DNA sequence information, this approach offers the opportunity to identify all gene products of E. coli and map their genes to within 10 kb on the E. coli genome; with sequence information, this approach can produce a definitive expression map of the E. coli genome.
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VanBogelen RA, Sankar P, Clark RL, Bogan JA, Neidhardt FC. The gene-protein database of Escherichia coli: edition 5. Electrophoresis 1992; 13:1014-54. [PMID: 1286664 DOI: 10.1002/elps.11501301203] [Citation(s) in RCA: 111] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The gene-protein database of Escherichia coli is both an index relating a gene to its protein product on two-dimensional gels, and a catalog of information about the function, regulation, and genetics of individual proteins obtained from two-dimensional gel analysis or collated from the literature. Edition 5 has 102 new entries--a 15% increase in the number of annotated two-dimensional gel spots. The large increase in this edition was accomplished in part by the use of a new method for expression analysis of ordered segments of the E. coli genome, which has resulted in linking 50 gel spots to their genes (or open reading frames) and another 45 to specific regions of the chromosome awaiting the availability of DNA sequence information. Communication of information from the scientific community resulted in additional identifications and regulatory information. To increase accessibility of the database it has been placed in the repository at the National Center for Biotechnology Information (NCBI) at the National Library of Medicine under the name ECO2DBASE. It will be updated twice yearly. This edition of the gene-protein database is estimated to contain entries for one-sixth of the protein-encoding genes of E. coli.
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Kimelberg HK, O'Connor ER, Sankar P, Keese C. Methods for determination of cell volume in tissue culture. Can J Physiol Pharmacol 1992; 70 Suppl:S323-33. [PMID: 1295683 DOI: 10.1139/y92-279] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In this paper we present an overview of methods for determining cell volume in both suspension and monolayer cultures. Data from the use of selected methods such as the Coulter counter system for suspension cultures and radiolabelled intracellular markers for substratum-attached, monolayer cultures are presented. The advantages, limitations, and conditions under which the different methods can be used are discussed. It is pointed out that there is a need for more direct physical methods for measuring dynamic changes in the cell volume of monolayer cultures without removing the cells from the substratum. Data from a method applicable to such cultures that measures extracellular impedance are presented.
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Kimelberg HK, Sankar P, O'Connor ER, Jalonen T, Goderie SK. Functional consequences of astrocytic swelling. PROGRESS IN BRAIN RESEARCH 1992; 94:57-68. [PMID: 1287732 DOI: 10.1016/s0079-6123(08)61739-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Neidhardt FC, Appleby DB, Sankar P, Hutton ME, Phillips TA. Genomically linked cellular protein databases derived from two-dimensional polyacrylamide gel electrophoresis. Electrophoresis 1989; 10:116-22. [PMID: 2659319 DOI: 10.1002/elps.1150100206] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In its most useful form a cellular protein database should be genomically based, because it is the genome which determines both the total number of proteins a cell can make and the particular ones that will be made under any given condition. Such a database should trace each protein back to its structural gene, and should account for every structural gene of a cell. Recent advances in molecular biology greatly facilitate the construction of such gene-protein databases. The mapping of genes of unidentified proteins resolved from total cell extracts on two-dimensional gels can now be accomplished by largely biochemical methods, without the necessity of isolating mutants or performing genetic crosses. Other techniques permit one to search gels for the product of any newly discovered gene (or open reading frame) suspected of encoding a protein. Consequently, gene-protein indices can be built independently and simultaneously from either direction--deducing the genetic map from the protein pattern, or finding the protein pattern from information encoded in the genome. A database of this sort is being constructed for the bacterium, Escherichia coli. Given the current pace of DNA nucleotide sequencing, the development of total gene-protein indices for a variety of cells can be anticipated in the near future.
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Sankar P, Shanmugam KT. Hydrogen metabolism in Escherichia coli: biochemical and genetic evidence for a hydF gene. J Bacteriol 1988; 170:5446-51. [PMID: 3056901 PMCID: PMC211636 DOI: 10.1128/jb.170.12.5446-5451.1988] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
A new gene whose product is essential for production of all three hydrogenase isoenzymes in Escherichia coli has been identified. This gene, termed hydF, mapped at 59 min in the E. coli chromosome and resided next to the hydB gene. The map order of these genes was hydE, hydF, hydB, fhlA, and fdv. The hydF gene was transcribed from its own promoter and coded for a protein with an apparent molecular weight of 43,000 to 44,000. Expression of the hydF operon was enhanced by anaerobic growth conditions. Partial products of the hydF gene were capable of supporting various levels of hydrogenase activity in a hydF mutant in the presence of the fhlA gene product, also produced from multicopy plasmids. In the presence of a second mutation in an unidentified, unlinked gene, hydrogenase activity in a hydF mutant was restored by plasmids which carried incomplete hydF and hydB+ genes. These results suggest that the products of hydF and fhlA interact with each other and with yet one other gene product.
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