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This paper suggests that like ethanol, methanol also produces certain changes in the steady state level of monoamines in hypothalamus and striatum of albino rats. Though, the toxic manifestations of methanol are attributed to the metabolic end product of methanol viz. formic acid by several workers, we report here that the methanol-induced brain monoamine changes, at least, could be attributed to the direct action of methanol rather than to its metabolic end products like formaldehyde or formate. Studies in the steady state level of rat brain monoamines have shown that after methanol administration (3 g/kg), there is severe depletion of dopamine level in striatum but a significant increase in the level of dopamine, serotonin and 5-hydroxy indole acetic acid in hypothalamus. At the same time, norepinephrine and epinephrine levels are reduced in hypothalamus as well as in striatum. These effects do not seem to be induced by metabolic acidosis. The changes in monoamine levels are very well correlated with the blood and brain level of methanol as evidenced by maintaining a higher methanol level either by simultaneous administration of ethanol or by blocking methanol metabolism by pretreatment with 4-methyl pyrazole and 3-amino-1,2,4-triazole. It is thus postulated that monoamine changes induced by methanol appear to be the direct effect of methanol per se on the monoaminergic neuronal membranes. 相似文献
3.
Changes in monoamines were studied in discrete areas of brain with varying dose of isopropanol. Acute administration of isopropanol (0.463 g/kg, 0.925 g/kg and 1.85 g/kg) decreased dopamine level in hypothalamus, pons medulla and cerebral cortex and whereas it was increased in striatum and cerebellum. Noradrenaline level was reduced in all the brain areas studied. Adrenaline level was increased in hypothalamus, striatum, midbrain and pons medulla, and decreased in hippocampus and cerebral cortex. Serotonin level was increased in hypothalamus, midbrain, pons-medulla and cerebral cortex, and decreased in striatum and hippocampus. These changes were dose-dependent. It is concluded that isopropanol causes changes in brain monoamine content that this effect is not the same in all the regions of the brain. 相似文献
4.
Abstract A young male motorcyclist presented to the Pelvic Unit with an open-book fracture of his pelvis and an acute obstructed direct
inguinal hernia. He was managed operatively and made an excellent recovery. Traumatic abdominal wall hernias are rare. This
is a unique combination of injuries that the trauma surgeon should be aware of. 相似文献
5.
Christopher L. Hansen Richard A. Goldstein Olakunle O. Akinboboye Daniel S. Berman Elias H. Botvinick Keith B. Churchwell C. David Cooke James R. Corbett S. James Cullom Seth T. Dahlberg Regina S. Druz Edward P. Ficaro James R. Galt Ravi K. Garg Guido Germano Gary V. Heller Milena J. Henzlova Mark C. Hyun Lynne L. Johnson April Mann Benjamin D. McCallister Robert A. Quaife Terrence D. Ruddy Senthil N. Sundaram Raymond Taillefer R. Parker Ward John J. Mahmarian 《Journal of nuclear cardiology》2007,14(6):e39-e60
6.
Daniel R. Einstein Blazej Neradilak Nayak Pollisar Kevin R. Minard Chris Wallis Michelle Fanucchi James P. Carson Andrew P. Kuprat Senthil Kabilan Richard E. Jacob Richard A. Corley 《Anatomical record (Hoboken, N.J. : 2007)》2008,291(12):1628-1648
We present the results of an automated analysis of the morphometry of the pulmonary airway trees of the Sprague–Dawley rat. Our work is motivated by a need to inform lower‐dimensional mathematical models to prescribe realistic boundary conditions for multiscale hybrid models of rat lung mechanics. Silicone casts were made from three age‐matched, male Sprague–Dawley rats, immersed in a gel containing a contrast agent and subsequently imaged with magnetic resonance (MR). From a segmentation of this data, we extracted a connected graph, representing the airway centerline. Segment statistics (lengths and diameters) were derived from this graph. To validate this MR imaging/digital analysis method, airway segment measurements were compared with nearly 1,000 measurements collected by hand using an optical microscope from one of the rat lung casts. To evaluate the reproducibility of the MR imaging/digital analysis method, two lung casts were each imaged three times with randomized orientations in the MR bore. Diameters and lengths of randomly selected airways were compared among each of the repeated imaging datasets to estimate the variability. Finally, we analyzed the morphometry of the airway tree by assembling individual airway segments into structures that span multiple generations, which we call branches. We show that branches not segments are the fundamental repeating unit in the rat lung and develop simple mathematical relationships describing these structures for the entire lung. Our analysis shows that airway diameters and lengths have both a deterministic and stochastic character. Anat Rec, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
7.
Differential PsaA-, PspA-, PspC-, and PdB-specific immune responses in a mouse model of pneumococcal carriage 下载免费PDF全文
Palaniappan R Singh S Singh UP Sakthivel SK Ades EW Briles DE Hollingshead SK Paton JC Sampson JS Lillard JW 《Infection and immunity》2005,73(2):1006-1013
Larger numbers of pneumococci were detected in the nasal tract compared to the lung, cervical lymph nodes, and spleen 1, 2, 4, 7, 14, and 21 days after nasal challenge with Streptococcus pneumoniae strain EF3030. In this mouse model of pneumococcal carriage, peripheral S. pneumoniae pneumococcal surface adhesin A (PsaA)-specific humoral responses (immunoglobulin G2a [IgG2a] > IgG1 = IgG2b > IgG3) were significantly higher than pneumococcal surface protein A (PspA)-specific, genetic toxoid derivative of pneumolysin (PdB)-specific, or pneumococcal surface protein C (PspC)-specific serum antibody levels. However, PspA-specific mucosal IgA antibody levels were significantly higher than those against PsaA, PdB, and PspC. In general, both PsaA- and PspA-specific lung-, cervical lymph node-, nasal tract-, and spleen-derived CD4(+) T-cell cytokine (interleukin-4, interleukin-6, granulocyte-macrophage colony-stimulating factor, gamma interferon, and tumor necrosis factor alpha) and proliferative responses were higher than those for either PspC or PdB. Taken together, these findings suggest that PsaA- and PspA-specific mucosal responses as well as systemic humoral and T helper cell cytokine responses are predominantly yet differentially induced during pneumococcal carriage. 相似文献
8.
Zafer Tandogdu Justin Collins Greg Shaw Jennifer Rohn Bela Koves Ashwin Sachdeva Ahmed Ghazi Alexander Haese Alex Mottrie Anup Kumar Ananthakrishnan Sivaraman Ashutosh Tewari Benjamin Challacombe Bernardo Rocco Camilo Giedelman Christian Wagner Craig G. Rogers Declan G. Murphy Dmitry Pushkar Gabriel Ogaya-Pinies James Porter Kulthe Ramesh Seetharam Markus Graefen Marcelo A. Orvieto Marcio Covas Moschovas Oscar Schatloff Peter Wiklund Rafael Coelho Rair Valero Theo M. de Reijke Thomas Ahlering Travis Rogers Henk G. van der Poel Vipul Patel Walter Artibani Florian Wagenlehner Kris Maes Koon H. Rha Senthil Nathan Truls Erik Bjerklund Johansen Peter Hawkey John Kelly 《BJU international》2021,127(6):729-741
9.
Abdul Azeez E P G. Anbu Selvi Garima Sharma Senthil Kumar A P 《The International journal of health planning and management》2021,36(1):83-99
The practice of allopathic medicine by informal healthcare practitioners (IHPs) is ubiquitous in India. However, a little is known about the patients' experiences and IHPs' perspectives. The core questions guided the present study were (1) why do urban poor approach IHPs for healthcare? (2) what are their experiences of availing services from IHPs? and (3) what are the perspectives of IHPs about their practice with the population they serve? A qualitative research design guided the study. The study was conducted in the Gurugram city of Haryana, India. Nine IHPs and twenty‐seven patients who fit into the pre‐established inclusion criteria were interviewed. The findings of the study underline the structural constrains of healthcare access to the poor in India and the mutual dependencies between IHPs and the urban poor. Three themes were emerged corresponding to the perspectives of IHPs, and five themes were generated, which describes patients' experiences and perspectives of availing treatment. The factors that attract and sustain patients to IHPs are a mixture of socio‐economic aspects, which include poverty, inaccessibility, unaffordability, inefficient public healthcare facilities, and the positive behavioural and treatment attributes of the practitioners. The study implies urgent policy interventions to ensure quality healthcare to urban poor. 相似文献
10.
Chronic cyanide intoxication from cassava has been implicated as the cause for a degenerative neuropathy known widely as tropical ataxic neuropathy. An attempt has been made in this study to identify the specific cause for neuropathy caused by cassava using Wistar strain albino rats as the experimental animal model. The results of cassava fed animals were compared with control animals, animals given cyanide, malnourished animals and malnourished animals fed cyanide, to identify the causative factors. This study revealed that though the behavioural pattern in motor coordination of the cassava fed animals was similar to the other groups studied, the neurochemical basis for the observed behavioural pattern was unique for cassava. Hence the neurotoxicity of cassava could be attributed to unmetabolized linamarin, more than its nutritional status and/or cyanide toxicity. 相似文献