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Raeis AR, Bahrami S, Yousefi M. Relationship between information literacy and creativity: a study of students at the isfahan university of medical sciences. Mater Sociomed 2013; 25:28-31. [PMID: 23687459 PMCID: PMC3655735 DOI: 10.5455/msm.2013.25.28-31] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 02/25/2013] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION In an era of huge volume of publications and information products, information literacy has become a very important survival tool. Information literacy is an instrument for individual empowerment that leads one to search for the truth and the desired information for decision making with independence. While creativity is the foundation of sciences and innovation, one of the main functions of universities is expanding the frontiers of knowledge and productions of scientific information. Therefore creativity is more vital and necessary for these kinds of institutions than other organizations. In this regard, this paper investigates the relationship between information literacy and creativity of students at the Isfahan University of Medical Sciences. METHOD This is a correlation-descriptive study. Statistical population was third year students of Isfahan University of Medical Sciences (1054 individuals) in 2011. Sample size was 250 individuals selected by stratified random Sampling. The instruments for data collection were two questionnaires, an investigator made questionnaire for information literacy and a creativity questionnaire. For questionnaires validity used content validity and for their reliability used Cronbach Alpha Coefficient (r1= 0.95, r2=0.85). SPSS 18 statistical software and descriptive and inferential statistics tests (Frequency distribution tab, Pearson Correlation, T test, Tukey test and ANOVA) were used to analyze data. RESULTS The results indicate that mean of information literacy was higher than average and mean of creativity was lower than average. There is a significant multiple correlation between 5 dimensions of information literacy (Ability to determine extent and nature of information, effective and efficient access, critical assessment, ability of purposeful application, ability of understanding legal and economic issues) and creativity in level of (p≤ 0.05). Also mean difference of ability of purposeful application based on gender was significant in level of (p≤ 0.05). It means the ability of purposeful application in male students was more than female students. CONCLUSION We are living in the information age and one of the variables that are associated with creativity is information literacy. The results indicated that the students who are more creative are more information literate and can reach higher goals. Therefore we can contemplate that increasing information literacy in the universities and other scientific education centers plays an important role in teaching and training a creative workforce.
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Raeven P, Weixelbaumer KM, Drechsler S, Klotz A, Jafarmadar M, Khadem A, Redl H, Bahrami S, Declerck PJ, Osuchowski MF. Homogeneity versus diversity: inhibition of plasma PAI-1 in murine sepsis proved lethal in homogeneous cohorts but not in all-inclusive populations. Crit Care 2012. [PMCID: PMC3504874 DOI: 10.1186/cc11760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Bahrami S, Hasanpour M, Rajaeepour S, Aghahosseni T, Hodhodineghad N. The relationship between organizational trust and nurse administrators' productivity in hospitals. IRANIAN JOURNAL OF NURSING AND MIDWIFERY RESEARCH 2012; 17:451-5. [PMID: 23922588 PMCID: PMC3733292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
CONTEXT Management of health care organizations based on employee's mutual trust will increase the improvement in functions and tasks. AIMS The present study was performed to investigate the relationship between organizational trust and the nurse administrators' productivity in educational health centers of in Health-Education Centers of Isfahan University of Medical Sciences. SETTINGS AND DESIGN This research was a descriptive and correlational study. MATERIALS AND METHODS The population included all nurse administrators. In this research, 165 nurses were selected through random sampling method. Data collection instruments were organizational trust questionnaire based on Robbins's model and productivity questionnaire based on Hersy and Blanchard's model. Validity of these questionnaires was determined through content validity and their reliability was calculated through Cranach's alpha. Statistical analysis was used: The data analysis was done using the SPSS (18) statistical software. RESULTS The indicators of organizational trust such as loyalty, competence, honesty, and stability were more than average level but explicitness indicator was at average level. The components of productivity such as ability, job knowledge, environmental compatibility, performance feedback, and validity were more than average level but motivation factor was at average level and organizational support was less than average level. There were a significant multiple correlations between organizational trust and productivity. Beta coefficients among organizational trust and productivity were significant and no autocorrelation existed and regression model was significant. CONCLUSIONS Committed employees, timely performing the tasks and developing the sense of responsibility among employees can enhance production and productivity in the health care organizations.
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Bahrami S, Hatam GR, Razavi M, Nazifi S. In vitro cultivation of axenic amastigotes and the comparison of antioxidant enzymes at different stages of Leishmania tropica. Trop Biomed 2011; 28:411-417. [PMID: 22041763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The present study aimed to establish a simple method to yield large amounts of Leishmania tropica amastigote-like forms in axenic cultures and to compare the superoxide dismutase (SOD) and glutathione peroxidase (GPX) enzymes at different stages of L. tropica. Different culture conditions were tested to find the optimum condition of axenic amastigotes generation. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities were determined at logarithmic and stationary phases and axenic amastigote stage of the parasite. A high proportion (88%) of amastigote-like forms of L. tropica was observed in BHI medium supplemented with 20% FCS, pH 4.5, and incubated at 37ºC with 5% CO(2). The results showed that SOD activity was at the lowest level in the logarithmic phase of promastigotes and increased towards the stationary phase of promastigotes and amastigote stage. The results showed that the optimum condition for differentiation of L. tropica promastigotes to axenic amastigotes was BHI medium containing 20% FCS at pH 4.5, incubated at 37ºC in the presence of 5% CO(2). It seems that SOD, but not GPX is a major determinant of intracellular survival of the parasite.
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Bernardi M, Bahrami S, Callen JP. Hypertrophic lupus erythematosus complicating long-standing systemic lupus erythematosus. Lupus 2011; 20:549-50. [PMID: 21300682 DOI: 10.1177/0961203310385161] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Bahrami S, Rajaeepour S, Rizi HA, Zahmatkesh M, Nematolahi Z. The relationship between students' study habits, happiness and depression. IRANIAN JOURNAL OF NURSING AND MIDWIFERY RESEARCH 2011; 16:217-21. [PMID: 22224110 PMCID: PMC3249802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Accepted: 03/11/2011] [Indexed: 11/06/2022]
Abstract
BACKGROUND One of the important requirements for cultural, social and even economic development is having a book-loving nation. In order to achieve this, there is a need for purposeful and continuous programming. The purpose of this research was to determine the relationship between students' study habits, happiness and depression in Isfahan University of Medical Science. METHODS This research was a kind of descriptive and correlation survey. Statistical population included all MSc and PhD students in the second semester of the Isfahan University of Medical Science (263 students). In this research, stratified and random sampling was used in which a sample of 100 students was selected. Data collection instruments were Beck Depression Inventory (BDI), Oxford Happiness Inventory and a researcher-made questionnaire to determine the amount of students' study. Validity of this questionnaires was determined by structure and content related validity and its reliability was calculated by Cronbach's alpha coefficient for the first (r = 0.94), second (r = 0.91) and third (r = 0.85) questionnaire. Analysis of research findings was done through descriptive and inferential statistics. RESULTS Findings showed that 68.8 percent of students study less than 5 hours and only 2.5 percent of students study more than 10 hours. 65 percent of students had high amount of happiness and 35 percent had medium amount of happiness. In 60 percent of students there was no symptom of depression and 7.5 had depression symptoms. Also, there was no significant relationship between happiness and studying but there was a significant and negative relationship between studying and depression and happiness and depression. CONCLUSIONS The amount of study and tendency for reading are among the most important indices of human growth in terms of potential abilities for achieving a perfect human life and to prevent one-dimensional thinking. Thus, finding ways to encourage students to study is considered essential to achieve a healthy and developed society.
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Razawi SM, Oryan A, Bahrami S, Mohammadalipour A, Gowhari M. Prevalence of Cryptosporidium infection in camels (Camelus dromedarius) in a slaughterhouse in Iran. Trop Biomed 2009; 26:267-273. [PMID: 20237440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Cryptosporidiosis is a zoonotic protozoan disease of worldwide distribution, affecting a wide range of vertebrate hosts. Most data on the biology, distribution pattern, pathology and prevalence of cryptosporidial infection in farm animals is restricted to cattle, sheep and goats. Limited data is available in other domestic herbivores including camel. Numerous camels (Camelus dromedarius) are raised in the semi-arid regions of Iran. Although camel is acknowledged as a potential source of contamination, little is known with regards to the prevalence of Cryptosporidium in this population except a case report on the occurrence of this infection in a bactrian camel (Camelus bactrianus) in China. This investigation was undertaken to determine the prevalence of Cryptosporidium infection in camels (C. dromedarius) from Najaf-Abad slaughterhouse, Isfahan Province, central part of Iran. Out of 103 faecal samples from 63 adult males and 40 adult females, 2-14 years old, 39 (37.9%) were found positive for oocysts. No significant differences were observed between males and females, and among different age groups. There was also no significant difference among infection intensity in different age groups. This is the first report of Cryptosporidium infection in camels from this country.
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Oryan A, Razavi SM, Bahrami S. Occurrence and biology of goat warble fly infestation by Przhevalskiana silenus (Diptera, Oestridae) in Iran. Vet Parasitol 2009; 166:178-81. [PMID: 19692181 DOI: 10.1016/j.vetpar.2009.07.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 07/09/2009] [Accepted: 07/22/2009] [Indexed: 11/16/2022]
Abstract
Goat warble fly infestation (GWFI) by the larvae of Przhevalskiana silenus is endemic in goats of semi-hilly and mountainous regions of Iran. This myiasis has severe economic impact on tanning industries, and it is responsible for impaired milk and meat production, growth retardation and carcass depreciation. To estimate the prevalence of GWFI in the southern areas of Iran, from October 2006 to December 2008, the carcasses of 8000 goats at a Shiraz slaughterhouse and 1000 each at Marvdasht and Darab cities were examined weekly for the presence of P. silenus larvae. In addition, appropriate sections from the skin and subcutaneous tissues were processed for histopathological investigation. The prevalence rate of infestation in different cities varied from 7.0% to 18.9% and the minimum and maximum infestation rate was 3 and 78, with an average rate of infestation of 26.2 warbles per animal. Significant differences were observed in the prevalence among different age groups with no significant difference between male and female animals. First instar larvae (L(1)) were found on infected animals from early August to end of September, second larval stage (L(2)) from early October to end of November and third-stage larvae (L(3)) from early December to mid-March. No larvae were found on skin or subcutaneous tissues from end of March to late July. Live L(1) initiated mild lymphocyte, macrophage and eosinophil infiltration while dead L(1) initiated granulomatous or pyogranulomatous reactions. Live L(2) induced severe inflammatory reaction and massive tissue necrosis, which continued for L(3) and until the end of infestation phase. The subcutaneous tissues, dermis and epidermis became necrotic and fragmented, and L(3) penetrated the necrotic area to start its aerobic life cycle.
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Bahrami S, Abbasi S, Ghorbani YA, Miran-Beigi AA. High sensitive determination of trace amount of cobalt by catalytic adsorptive stripping voltammetry. RUSS J ELECTROCHEM+ 2009. [DOI: 10.1134/s1023193509020128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Osuchowski M, Weixelbaumer K, Raeven P, Remick D, Reise K, Kozlov A, van Griensven M, Redl H, Bahrami S. Multiple organ dysfunction syndrome: the scapegoat? Assessment of organ dysfunction between surviving and dying mice in the acute phase of polymicrobial sepsis. Crit Care 2009. [PMCID: PMC2776221 DOI: 10.1186/cc8104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Vahabi A, Lotfi A, Solouki M, Bahrami S. Molecular and Morphological Markers for the Evaluation of Diversity Between Plantago ovata in Iran. ACTA ACUST UNITED AC 2008. [DOI: 10.3923/biotech.2008.702.709] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Oryan A, Valinezhad A, Bahrami S. Prevalence and pathology of camel filariasis in Iran. Parasitol Res 2008; 103:1125-31. [PMID: 18629537 DOI: 10.1007/s00436-008-1104-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Accepted: 06/16/2008] [Indexed: 10/21/2022]
Abstract
A total of 1,070 camels of different ages and of both sexes slaughtered at Mashhad slaughterhouse were inspected for infection with Dipetalonema evansi. Microfilariae were found in peripheral blood smears of 221 (20.7%) camels (14% females and 23% males). In a second study, the testicles, epididymises, spermatic cords, and lungs of 197 male camels were examined, and 165 (83.7%) were infected with adult forms of D. evansi. Tissue sections from 30 infected and ten uninfected camels were collected and processed routinely for further histopathological studies. The arteries infected with D. evansi in the region of nodules in testis showed chronic reaction characterized by proliferative and hyperplastic changes of the endothelial and fibrous connective tissue layers, narrowing the lumen or occluding it. The testicles were either hypertrophic or atrophic and showed chronic orchitis with infiltration of lymphocytes, eosinophils, macrophages and fibroblasts, parenchymal degeneration, and necrosis and, in some cases, with hematoma and hydrocele formation. Necrosis of the alveolar walls, atelectasis, pulmonary edema, and fibrosis of the pulmonary parenchyma with chronic interstitial pneumonia and rarely mineralization of the wall of the blood vessels were also seen in some of the infected animals. D. evansi is highly endemic and constitutes an important health problem to camels in this area, resulting in high morbidity, impaired working capacity, and lowered productivity.
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Bahrami S, Malone J, Webb K, Callen J. Tissue Eosinophilia as an Indicator of Drug-Induced Leukocytoclastic Vasculitis: A Clinicopathologic Investigation. J Cutan Pathol 2008. [DOI: 10.1111/j.0303-6987.2005.0320o.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Gholivand M, Bahrami S, Abbasi S, Sohrabi A. Simultaneous Determination of Nickel and Cadmium by Adsorptive Stripping Voltammetry. ELECTROANAL 2008. [DOI: 10.1002/elan.200704183] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Odim J, Banerji A, Bahrami S, Laks H. Is Third-Time Heart Retransplantation Justifiable? Transplant Proc 2006; 38:1516-9. [PMID: 16797347 DOI: 10.1016/j.transproceed.2006.02.080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Indexed: 11/19/2022]
Abstract
Since repeat heart transplantation traditionally carries higher risk than primary engraftment, we tested the hypothesis that third-time cardiac allograft transplantation is associated with prohibitive mortality and morbidity. The cohort of all third-time cardiac retransplants performed at our institution (n=3) and reported to UNOS from 1987 to 2002 (n=10) was reviewed. The primary endpoints were early and late mortality. Extending the study frame through 2003 captures a total of 5 and 15 third-time heart transplant recipients in UCLA and UNOS databases, respectively. Of the 15 patients undergoing third-time retransplants, preoperatively one was ventricular assist device-dependent, four were on intravenous inotropes, and two had creatinine levels greater than 2.5. Additionally, four were male recipients of female donor hearts and the mean donor ischemic time was 2.6 hours. One patient was diagnosed with acute allograft rejection, 13 with coronary artery vasculopathy/chronic rejection, and one with primary graft failure. At our institution, five patients underwent a third heart transplant. There was no early or hospital mortality. One patient died late from transplant coronary artery disease and another following a fourth allograft. The mortality rate for third-time heart allograft recipients is acceptable. These results are influenced by small sample size, younger age, case selection, and operations at select, high-volume institutions with significant experience.
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Feder A, Fitzal F, Jafarmadar M, Kober C, Allbrecht M, Redl H, Bahrami S. PANCREATIC PROTEASES INHIBITION IS NOT EFFECTIVE IN AMELIORATING PERITONITISINDUCED CELL ACTIVATION, ORGAN DAMAGE, AND MORTALITY IN RATS. Shock 2006. [DOI: 10.1097/00024382-200606001-00212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Assadian A, Assadian O, Senekowitsch C, Rotter R, Bahrami S, Fürst W, Jaksch W, Hagmüller GW, Hübl W. Plasma D-lactate as a potential early marker for colon ischaemia after open aortic reconstruction. Eur J Vasc Endovasc Surg 2005; 31:470-4. [PMID: 16376117 DOI: 10.1016/j.ejvs.2005.10.031] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Accepted: 10/30/2005] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND AIM The breakdown of mucosal barrier function due to intestinal hypo-perfusion is the earliest dysfunction of ischaemic colitis. Severe colon ischaemia after aortic reconstruction is associated with mortality rates up to 90%. Therefore, early detection and treatment of patients with extensive ischaemic colitis is of crucial importance. In experimental studies, both D-lactate and bacterial endotoxin have been reported as markers of intestinal mucosal barrier impairment. However, evidence of their value in clinical practice is lacking. The aim of this pilot prospective cohort study was to assess the association between ischaemia of the colon (assessed histologically) and plasma levels of D-lactate and endotoxin in patients undergoing open aortic reconstruction. PATIENTS AND METHODS Twelve consecutive patients underwent surgery between February and April 2003. Six patients underwent emergency surgery and six patients elective aortic surgery. D-Lactate and endotoxin levels were measured in blood samples collected according to a standardised protocol. For histological examination biopsies were obtained by sigmoidoscopy on days 4-6 after surgery, or earlier if indicated clinically. RESULTS As early as 2 h postoperatively, elevated plasma levels of d-lactate were measured in patients with histologically proven ischaemic colitis. The peak of D-lactate elevation was on postoperative days 1 and 2. Concentration of plasma endotoxin was not significantly different in patients with or without ischaemic colitis. CONCLUSION Our data suggest that plasma D-lactate levels are a useful marker for early detection of ischaemic colitis secondary to aortic surgery.
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Banerji A, Bahrami S, Laks H, Odim JN. 551 IS THIRD-TIME HEART RETRANSPLANTATION JUSTIFIABLE? J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Pelinka LE, Szalay L, Jafarmadar M, Schmidhammer R, Redl H, Bahrami S. Circulating S100B is increased after bilateral femur fracture without brain injury in the rat. Br J Anaesth 2003; 91:595-7. [PMID: 14504167 DOI: 10.1093/bja/aeg225] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND S100B is an acknowledged marker of brain damage. However, trauma without brain damage also causes an increase in S100B. S100B concentrations are highest in multiple trauma patients with long bone fractures. Clinically, extensive long bone fractures are associated with haemorrhagic shock and haemorrhagic shock per se is associated with increased S100B. The aim of our experimental study was to verify the S100B increase in long bone fracture without haemorrhagic shock. METHODS and results. Bilateral femur fracture was carried out in 10 anaesthetized rats. Blood samples were drawn for immuno-luminometrical S100B measurement 5, 15, 30, 120, and 240 min after fracture. Mean arterial pressure (MAP), heart rate, and body temperature were monitored continuously. S100B increased after bilateral femur fracture and reached a peak 30-120 min after fracture (P<0.001). MAP remained at a level which is not associated with shock in rats. Heart rate and body temperature remained unchanged. Autopsy verified open bilateral femur fracture surrounded only by small zones of clotted blood. CONCLUSIONS S100B is increased in bilateral femur fracture without haemorrhagic shock in rats. This finding suggests that bone marrow is a potential extracerebral source of S100B.
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Bahrami S, Sobhian B, Kozlov A, Duvigneau C, Nohl H, Jafarmadar M, Redl H. Nitric oxide synthase-independent pathway(s) of nitric oxide formation after intestinal ischaemia–reperfusion. Br J Surg 2002. [DOI: 10.1046/j.1365-2168.2000.01544-4.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Background
Recent evidence suggests that nitric oxide produced in the gastrointestinal tract, in concert with other vasoactive mediators, plays an essential role in the regulation of splanchnic circulation.
Methods
To determine the sites and pathways of nitric oxide formation, electron paramagnetic resonance spectroscopy and the nitric oxide trap diethyldithiocarbamate-Fe were used to detect directly nitric oxide formed in intestine, liver and lungs of rats subjected to local intestinal ischaemia–reperfusion (I/R), in the presence or absence of nitric oxide donors or inhibitors. In addition, the role of nitric oxide in control of the gastrointestinal circulation was determined by means of a coloured microsphere technique employing N-(G)-Monomethyl-L-arginine (L-NMMA) in rats subjected to haemorrhagic shock followed by resuscitation.
Results
In contrast to remote organs lung and liver (no change), intestinal I/R resulted in an increase in nitric oxide formation in intestinal tissues. Administration of the non-specific nitric oxide inhibitor L-NMMA caused a decrease in I/R-independent basal nitric oxide levels in lung and liver but did not influence the I/R-induced increase in nitric oxide formation in intestinal tissues. In support of this, reverse transcriptase–polymerase chain reaction analyses showed inducible nitric oxide synthase (NOS) expression in the lung but not in intestinal tissues. In the microsphere experiment, a moderate and therapeutic dose of L-NMMA administered after the completion of resuscitation, which improved haemodynamic conditions and outcome, did not alter the intestinal circulation.
Conclusion
The data suggest that the early-phase I/R-induced nitric oxide formation in ischaemic intestinal tissue is probably NOS independent, while nitric oxide formation in normoxic remote tissues is partially NOS dependent. In addition, the authors' nitric oxide-related therapeutic approaches reveal that only the regulation of nitric oxide (e.g. nitric oxide supplementation during resuscitation or reperfusion and/or nitric oxide inhibition or modulation after resuscitation) may protect against hypovolaemic insults.
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Nohl H, Staniek K, Sobhian B, Bahrami S, Redl H, Kozlov AV. Mitochondria recycle nitrite back to the bioregulator nitric monoxide. Acta Biochim Pol 2002; 47:913-21. [PMID: 11996114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Nitric monoxide (NO) exerts a great variety of physiological functions. L-Arginine supplies amino groups which are transformed to NO in various NO-synthase-active isoenzyme complexes. NO-synthesis is stimulated under various conditions increasing the tissue of stable NO-metabolites. The major oxidation product found is nitrite. Elevated nitrite levels were reported to exist in a variety of diseases including HIV, reperfusion injury and hypovolemic shock. Denitrifying bacteria such as Paracoccus denitrificans have a membrane bound set of cytochromes (cyt cd1, cyt bc) which were shown to be involved in nitrite reduction activities. Mammalian mitochondria have similar cytochromes which form part of the respiratory chain. Like in bacteria quinols are used as reductants of these types of cytochromes. The observation of one-e- divergence from this redox-couple to external dioxygen made us to study whether this site of the respiratory chain may also recycle nitrite back to its bioactive form NO. Thus, the aim of the present study was therefore to confirm the existence of a reductive pathway which reestablishes the existence of the bioregulator NO from its main metabolite NO2-. Our results show that respiring mitochondria readily reduce added nitrite to NO which was made visible by nitrosylation of deoxyhemoglobin. The adduct gives characteristic triplet-ESR-signals. Using inhibitors of the respiratory chain for chemical sequestration of respiratory segments we were able to identify the site where nitrite is reduced. The results confirm the ubiquinone/cyt be1 couple as the reductant site where nitrite is recycled. The high affinity of NO to the heme-iron of cytochrome oxidase will result in an impairment of mitochondrial energy-production. "Nitrite tolerance" of angina pectoris patients using NO-donors may be explained in that way.
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Ackermann M, Reuter M, Flohé S, Bahrami S, Redl H, Schade FU. Cytokine synthesis in the liver of endotoxin-tolerant and normal rats during hemorrhagic shock. JOURNAL OF ENDOTOXIN RESEARCH 2001; 7:105-12. [PMID: 11521090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
In the present study the effects of endotoxin tolerance on hemorrhagic shock were investigated with particular focus on hepatic alterations. The following questions were addressed: (i) does hemorrhagic shock induce cytokine formation and heat shock response in the liver; and (ii) does endotoxin tolerance alter these reactions. Endotoxin tolerance was induced by repetitive daily injections of LPS for 5 days. Hemorrhagic shock was induced by hypovolemia (MAP 35 +/- 5 mmHg). After 3 h, the animals were resuscitated by re-infusion of homologous blood. m-RNA was isolated from liver biopsies and the mRNA levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), interleukin-10 (IL-10) and heat shock protein 70 (HSP-70) were determined by RT-PCR. TNF-alpha was measured by ELISA in serum samples and in the supernatants of whole blood cultures. It was found that endotoxin tolerance reduced mortality caused by hemorrhagic shock from 80% to 20%. In parallel, TNF-alpha production in response to LPS in vivo and in vitro was significantly decreased. During hemorrhage and after resuscitation. increased mRNA levels were detected in hepatic biopsies for TNF-alpha, IL-6, IL-10 and HSP-70, with highest levels immediately after re-infusion. Endotoxin-tolerant rats produced significantly lower levels of TNF-alpha, while no differences were found for IL-10 and HSP-70. Within 30 min after reperfusion, significantly higher levels of IL-6 mRNA were found in hepatic biopsies from tolerant rats; these differences disappeared 2 h after reperfusion.
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Etessami S, Tarsitani C, Lias M, Broadous M, Conger N, Randol G, Delory M, Bahrami S, Lee JH, Randall G. A unique murine monoclonal antibody recognizing HLA-B53, B37, B51, B52, +/-B44. Hum Immunol 2001; 62:732-8. [PMID: 11423180 DOI: 10.1016/s0198-8859(01)00254-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Monoclonal antibodies have played an important role in studying the biochemistry of the HLA-Class I molecules. Some murine anti-HLA mAbs can identify configurations of HLA epitopes that have never been reported in human allosera. One of these configurations is identified by an IgM mAb designated as: BHA-1441. This antibody was produced using a lymphoblastoid cell line typed as: A*02, A*25; B*38, B*4402/4405; C*0501, C*07, BW4, as the immunogen. A lymphocytotoxicity test of this mAb over a panel of 109 frozen, 452 fresh and, later, 44 DNA typed T cells revealed its specificity as B53, 37, 51, 52, +/- 44. All of the antigens recognized by this mAb share the Bw4 motif at positions 81-83, except for the HLA-B37, which shares only 82L and 83R. Furthermore, while B37 and B44 cross-react due to the aspartic acid (D) substitution at position 156, the reactivity with B53, B5 (51,52), B37 and 60% of B44 cells, makes it unlikely that the target epitope could be due only to the primary amino-acid sequence. The antibody-binding site might involve changes in tertiary structure and peptides bound by the MHC. BHA-1441 is an interesting tool to study and type the HLA-B53 antigen and its cross-reactive epitopes.
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Kozlov AV, Sobhian B, Costantino G, Nohl H, Redl H, Bahrami S. Experimental evidence suggesting that nitric oxide diffuses from tissue into blood but not from blood into tissue. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1536:177-84. [PMID: 11406352 DOI: 10.1016/s0925-4439(01)00047-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The aim of this study was to evaluate in vivo whether nitric oxide (NO) is able to diffuse from blood into tissues and vice versa from tissues into blood. We used an in vivo model of intestinal ischemia (superior mesenteric artery occlusion) selectively increasing NO levels in intestinal tissue and an infusion of L-arginine selectively increasing NO levels in blood. In this model we followed formation of nitrosyl complexes of hemoglobin (Hb-NO) in blood and nitrosyl-diethyldithiocarbamate-iron complexes (DETC--Fe--NO) in ischemic intestine and normoxic tissues by means of electron paramagnetic resonance spectroscopy. NO trapping by DETC--Fe in the tissues resulted in a reduction of Hb--NO levels in blood accompanied by the formation of water-insoluble DETC--Fe-NO complexes in ischemic intestine and normoxic tissues both during ischemia and during reperfusion. Administration of L-arginine increased NO levels in blood but neither in ischemic intestine nor in normoxic tissue. Our data suggest that NO released in blood from endothelial cells does not diffuse into tissue. In contrast, NO formed in tissue diffuses into blood. The latter indicates that NO formed in tissues may exert its biological activities systematically.
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Kozlov AV, Sobhian B, Duvigneau C, Gemeiner M, Nohl H, Redl H, Bahrami S. Organ specific formation of nitrosyl complexes under intestinal ischemia/reperfusion in rats involves NOS-independent mechanism(s). Shock 2001; 15:366-71. [PMID: 11336196 DOI: 10.1097/00024382-200115050-00006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Intestinal ischemia/reperfusion may lead to local and distant organ damage involving nitric oxide (NO). NO rapidly reacts with heme/non-heme-iron-yielding nitrosyl complexes, which can be determined directly by electron paramagnetic resonance spectroscopy. The aim of the present study was to characterize nitrosylation reactions induced by transient intestinal ischemia in blood and tissues. We used electron paramagnetic resonance spectroscopy and reverse transcription polymerase chain reaction analyses to estimate nitrosyl complex levels and inducible NO synthase mRNA expression in rats subjected to superior mesenteric artery occlusion for 60 min followed by the reperfusion. Nitrosyl hemoglobin concentrations in circulating blood were significantly increased during ischemia and reperfusion. Nitrosyl hemoglobin complexes were detected in ischemic intestine, but not in normoxic lung and liver or reperfused intestine. Administration of N-G-monomethyl-L-arginine, a non-specific NO synthase inhibitor, did not affect the formation of circulating nitrosyl complexes. Moreover, inducible NO synthase mRNA was not found in intestinal tissues at 30 min of reperfusion. Our data suggest an organ-specific NO formation indicated by the increased nitrosylation reaction in ischemic intestinal tissue, but not in the distant normoxic organs, in spite of high circulating nitrosyl hemoglobin levels. NO involved in nitrosylation under intestinal ischemia/reperfusion is probably formed by NO synthase-independent mechanism(s).
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