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1.
Mater Today Proc ; 47: 3716-3719, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33614415

RESUMEN

The COVID-19 coronavirus pandemic is an unparalleled threat intoday's quickly developing climate, and we face it as a global community. Like climate change, it is challenging our resilience from environmental health, social security, and government, to knowledge exchange and economic policy in all sectors of the economy and all fields of growth. So much as climate change, everybody's coming together would require the initiative. Throughout Europe and America, several organizations have mobilized to ensure that the neediest are not left behind, encouraging emergencies and disruptions avoidance and preparedness. The coronavirus outbreak has highlighted the growing community's strengths and vulnerabilities that it has influenced, and has provided us with the ability to benefit from each other's accomplishments and shortcomings. The comparison graph has also been shown in this paper displaying European and American scenarios. The globe might feel smaller amid disaster states and global travel bans, but it is a period when teamwork and looking outward were never more relevant.

2.
ISA Trans ; 58: 659-66, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26296287

RESUMEN

The paper discusses the development of the ring shaped force transducers for measurement of force in lower capacity to meet the industrial requirements with the increasing technological developments. A 50 N ring shaped force transducer for tension mode has been developed by studying the analytical and computational methods. The force transducer developed has been metrologically studied according to the calibration procedure based on the standard ISO 376 and uncertainty of measurement of the force transducer is found to be±0.10% (k=2), while taking into account the relative uncertainty contribution due to necessary factors like repeatability, reproducibility, zero offset, interpolation, resolution and reversibility. The force transducer developed may further be studied for improvement of metrological performance and may suitably be developed for other lower capacities like 10 N, 20 N etc. The force transducer developed offers very economical alternative of complex shaped force transducers with simple design and manufacturing features. The force transducer developed may be proved very helpful in providing traceability to the user industries and calibration laboratories in the lower range of force measurement and serve as force transfer standard.

4.
Neurol India ; 44(4): 183-186, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-29542526

RESUMEN

Brainstem auditory evoked potentials (BAEP) and somatosensory evoked potentials (SSEP) were recorded in 10 patients of heatstroke. Glasgow coma scale was used to assess level of consciousness. Values of either BAEP and/or SSEP were abnormal in all patients. Most consistent abnormalities of BAEP were delayed peak, latency of wave III & V and delayed IPL of III-V & I-V. The most consistent abnormality of SSEP were delayed absolute peak, latency of N20 and delayed IPL of N13-N20 (CCT). Distorted N20 was observed in 40 percent patients. The delay in conduction of electrical activities throughout the central nervous system in the patients, resulting in abnormal values of either BAEP and/or SSEP probably due to cerebral oedema with extensive parenchymatous degeneration of cells in brain, either from hyperpyrexia per se or from petechial haemorrhage in the brain, as reported on autopsy material by earlier workers.

5.
Brain Behav Immun ; 7(3): 231-42, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8219412

RESUMEN

Two lines of mice which were selectively bred for high (Long Sleep; LS) and low (Short Sleep; SS) reactivities to a sedative dose of ethanol, are also differentiated by agents that act at the GABAA-receptor complex. Since this supramolecular complex may also modulate immune function, measures of immunity have been examined in these lines. In the present study the immune responsiveness before and after an allogeneic priming stimulus was investigated. Lower mitogen-induced T-cell proliferation, mixed leukocyte reaction, and cytotoxic T lymphocyte activity were found in unprimed LS compared to unprimed SS mice. In contrast, the LS line exhibited a marked augmentation of these responses after priming, while the SS mice appeared unresponsive to this challenge. Addition of splenocytes or cell-free splenic cultures from primed mice to cultures from unprimed mice suggested that differences in priming-induced cell-to-cell interactions, rather than the release of a soluble helper factor(s) into the medium, are responsible for the marked augmentation of the secondary response in LS, compared to SS mice. Fewer T-helper and T-suppressor/cytotoxic cells were found in LS compared to SS mice, and this was unaffected by priming. These results extend previous findings demonstrating a higher natural killer cell activity and rate of tumor rejection in LS mice and suggest that these lines may be useful in studying the regulatory role of the GABAA complex in immune function.


Asunto(s)
Etanol/farmacología , Inmunidad Celular/efectos de los fármacos , Inmunocompetencia/genética , Memoria Inmunológica/efectos de los fármacos , Ratones Endogámicos/inmunología , Neuroinmunomodulación/efectos de los fármacos , Receptores de GABA/fisiología , Sueño/genética , Animales , Cruzamientos Genéticos , Pruebas Inmunológicas de Citotoxicidad , Inmunocompetencia/fisiología , Activación de Linfocitos/efectos de los fármacos , Subgrupos Linfocitarios/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos/fisiología , Receptores de GABA-A/fisiología , Selección Genética
6.
Br J Cancer ; 67(5): 1026-30, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8494695

RESUMEN

Psychosocial factors are thought to influence risk and survival from cancer. We have previously studied specific behaviours in transgenic male CD-1 MT42 mice, which overexpress the gene encoding human transforming growth factor alpha (TGF alpha) in multiple tissues, and which develop a high incidence of spontaneous hepatocellular carcinoma. The male TGF alpha mice spent a lengthened time immobile in the swim test, were highly aggressive, had increased plasma levels of 17 beta-estradiol (E2), and reduced natural killer (NK) cell activity. The female transgenic MT42 TGF alpha mice do not develop an increased rate of tumours at any site. We hypothesised that if the alterations in male TGF alpha mice are associated with their development of hepatocellular carcinomas, female TGF alpha should not show these alterations. The data in the present study indicate that female TGF alpha mice display shortened immobility in the swim test, suggesting an improved ability to cope with stress, and appear less aggressive in the resident-intruder test than non-transgenic female CD-1 mice. The female TGF alpha mice also exhibit a 3-fold increase in the plasma levels of E2, and a 3-fold increase in NK cell activity. These findings suggest that the elevated expression of TGF alpha in the transgenic mice is associated with gender-specific behavioural alterations, and the development of spontaneous hepatocellular tumours in the males. Furthermore, TGF alpha alters hormonal and immune parameters similarly in both sexes. It remains to be determined whether the development of hepatocarcinoma in the male TGF alpha animals is associated with an impaired ability to cope with stress and elevated aggressive tendencies and/or whether manipulations leading to an impaired ability to cope with stress will promote tumourigenesis in female TGF alpha mice.


Asunto(s)
Conducta Animal/fisiología , Factor de Crecimiento Transformador alfa/fisiología , Agresión/fisiología , Animales , Peso Corporal , Depresión/fisiopatología , Estradiol/sangre , Estro , Femenino , Células Asesinas Naturales/inmunología , Hígado/anatomía & histología , Masculino , Ratones , Ratones Transgénicos , Páncreas/anatomía & histología , Factores Sexuales , Estrés Fisiológico/fisiopatología , Testosterona/sangre
7.
J Med Chem ; 36(9): 1284-90, 1993 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-8487266

RESUMEN

We report on the synthesis of two fluorine-18 labeled analogs of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). A piperidyl triazene was fluorinated to produce [18F]-1-methyl-4-(2-fluorophenyl)-1,2,3,6-tetrahydropyridine (2'-F-MPTP, 12) in very low yield, and 1-methyl-4-[2-(fluoromethyl)phenyl]-1,2,3,6-tetrahydropyridine (2'-FCH2-MPTP, 11) was labeled with 18F by nucleophilic displacement of the corresponding chloride in 60% yield. The biodistribution in mice of the latter radiotracer and its oxidation to 1-methyl-4-[2-(fluoromethyl)phenyl]pyridinium (2'-FCH2-MPP+, 6) is also reported. The kinetics of oxidation of 2'-FCH2-MPTP and its solvolysis products (the corresponding 2'-hydroxymethyl and 2'-chloromethyl analogs) by rat liver monoamine oxidase were investigated. 2'-FCH2-MPTP accumulated to a useful degree in the brain, was oxidized by monoamine oxidase in vitro, was converted to the oxidation product in brain in vivo, and had a neurotoxic potency similar to that of MPTP. We feel it may be useful as an 18F-labeled radiopharmaceutical for positron tomographic studies of the mechanisms of MPTP toxicity.


Asunto(s)
1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/análogos & derivados , Enfermedades del Sistema Nervioso/inducido químicamente , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/síntesis química , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/química , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/metabolismo , Animales , Radioisótopos de Flúor , Hidrólisis , Marcaje Isotópico , Cinética , Hígado/enzimología , Intoxicación por MPTP , Masculino , Ratones , Estructura Molecular , Monoaminooxidasa/metabolismo , Oxidación-Reducción , Ratas , Ratas Wistar , Distribución Tisular
8.
Chem Res Toxicol ; 6(1): 19-22, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8448343

RESUMEN

The reaction of trans-4-hydroxy-2-nonenal (4-HNE) with primary amines was investigated to elucidate chemistry that may clarify the nature of its physiological covalent binding with protein-based primary amino groups. Such binding of 4-HNE, generated endogenously from lipid peroxidation, appears to be a pathophysiologic factor in the modification of low-density lipoprotein and perhaps other instances. We now show that 4-HNE reacts with primary amines in aqueous acetonitrile at pH 7.8 to afford after workup, in 14-23% yield, the corresponding pyrroles, which were characterized by independent synthesis from 4-oxononanal. Additional, mostly unstable adducts are also formed, some of which eventually "age" to the pyrrole. Hydride reduction after initial adduct formation permits the isolation of more stable materials, one of which has been identified as the reduced amine Michael addition product. Pyrrole formation may constitute a physiologically important reaction of 4-hydroxyalkenals.


Asunto(s)
Aldehídos/química , Pirroles/química , Aminas/química , Bencilaminas/química , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Oxidación-Reducción , Fenetilaminas/química , Compuestos de Sulfhidrilo/química
9.
J Immunol ; 149(5): 1707-13, 1992 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-1354680

RESUMEN

After infection with LP-BM5 murine leukemia viruses, susceptible strains of mice develop a severe and progressive immunodeficiency disease, termed murine AIDS (MAIDS), features of which include markedly impaired T cell response to mitogens or specific Ag stimulation and decreased production of IL-2. Since an elevation of intracellular calcium concentration resulting from binding of Ag to the TCR is associated with IL-2 production, T cells from mice either uninfected or infected with LP-BM5 murine leukemia viruses were examined by a calcium mobilization assay. Both CD4+ and CD8+ T cells from infected mice manifested impaired calcium mobilization responses upon in vitro stimulation with anti-CD3 mAb or Con A. The abnormalities appeared early after virus inoculation and showed no difference in time course between subsets of T cells. Frequencies of prestimulation calcium-positive cells among both CD4+ and CD8+ cells in mice with MAIDS were significantly higher than those for uninfected mice. These abnormalities were associated with presence of the MAIDS-inducing defective virus genome, but were not induced by infection of mice genetically resistant to development of MAIDS or with nonpathogenic helper murine leukemia virus, a virus component that induces high spontaneous proliferation of T cells, even in MAIDS-resistant mice.


Asunto(s)
Linfocitos T CD4-Positivos/metabolismo , Antígenos CD8/análisis , Calcio/metabolismo , Síndrome de Inmunodeficiencia Adquirida del Murino/metabolismo , Linfocitos T/metabolismo , Animales , Células Cultivadas , Femenino , Interleucina-2/biosíntesis , Virus de la Leucemia Murina , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Síndrome de Inmunodeficiencia Adquirida del Murino/inmunología , Receptores de Antígenos de Linfocitos T/fisiología
10.
FASEB J ; 6(11): 3008-13, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1644264

RESUMEN

Mice infected with an immunosuppressive murine leukemia virus (MuLV) mixture, LP-BM5, displayed profound and selective deficits in spatial learning in a modified Morris water maze. These deficits appeared before the appearance of gross neurological impairment or histopathological changes in the central nervous system. Thus, LP-BM5-infected mice displayed deficits in several aspects of trained performance compared to controls. Furthermore, a failure to exhibit any evidence of task acquisition in this maze was observed almost twice as frequently (P less than 0.0005) in infected mice as in uninfected controls. Moreover, in the absence of gross visual, motoric, or motivational impairment, LP-BM5 MuLV-infected animals exhibited neither the target directed search pattern nor the spatial preference characteristic of controls. The spatial learning and memory deficit described here is the first report of cognitive impairment accompanying viral-induced immunosuppression in a nonprimate species.


Asunto(s)
Aprendizaje , Síndrome de Inmunodeficiencia Adquirida del Murino/psicología , Animales , Modelos Animales de Enfermedad , Masculino , Memoria , Ratones , Ratones Endogámicos C57BL
11.
Brain Res ; 588(1): 97-103, 1992 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-1393573

RESUMEN

The expression of transforming growth factor alpha (TGF alpha) is widely distributed throughout many normal and neoplastic tissues, but its physiological significance remains unclear. We have utilized male transgenic mice overexpressing the gene encoding human TGF alpha in multiple tissues to further identify those functions which are influenced by this protein. Male TGF alpha mice develop hepatocellular carcinoma at the age of 10-15 months. At the age of 2-3 months these mice, compared to age matched CD-1 controls, spent significantly longer times immobile in Porsolt's swim test, a model of stress and depressive behavior, and exhibiting aggressive behavior in the resident-intruder test. In contrast, the transgenic TGF alpha mice did not differ from the controls in either the plusmaze test of anxiety, or in their voluntary alcohol intake. Significantly, the TGF alpha mice exhibited a 25% lower Natural Killer (NK) cell activity and a four-fold increase in the plasma levels of 17-beta-estradiol (E2) than the controls. No significant changes in plasma testosterone or corticosterone levels were noted. The results indicate that transgenic male mice overexpressing TGF alpha exhibit behaviors characteristic of both an impaired ability to cope with stress and an increased aggressivity. The TGF alpha mice also show reduced NK cell activity and increased plasma estradiol concentrations. The present data suggest that TGF alpha may be important in influencing behavioral, immunological and hormonal systems prior to the onset of tumors. It remains to be determined whether hepatocarcinoma is associated with the direct proliferative and transforming effects of TGF alpha and/or indirect effects mediated through immune, hormonal and behavioral mechanisms.


Asunto(s)
Conducta Animal/efectos de los fármacos , Células Asesinas Naturales/fisiología , Esteroides/sangre , Factor de Crecimiento Transformador alfa/biosíntesis , Agresión/efectos de los fármacos , Consumo de Bebidas Alcohólicas/psicología , Animales , Peso Corporal/efectos de los fármacos , Corticosterona/sangre , Masculino , Ratones , Ratones Transgénicos , Factor de Crecimiento Transformador alfa/genética
12.
Brain Res ; 587(2): 250-6, 1992 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-1381982

RESUMEN

The role of inflammatory cytokines in the pathogenesis of neurological diseases is not well understood. The neurotoxic effects of cytokines could be mediated by immunostimulation of glial cells to produce toxic concentrations of nitric oxide (NO) and reactive nitrogen oxides. Cultured microglia and meningeal fibroblasts, but not Type 1 astrocytes, were induced by lipopolysaccharides and cytokines to synthesize NO and reactive nitrogen oxides from L-arginine. In co-cultures of immunostimulated microglia and cerebellar granule neurons, neurotoxicity was blocked by an inhibitor of NO synthase, NG-nitroarginine, and by oxyhemoglobin, which inactivates NO. Microglial-induced neurotoxicity was also partially attenuated by the N-methyl-D-aspartate (NMDA) receptor antagonists, MK-801 and 2-amino-5-phosphovalerate (APV). Superoxide dismutase, which stabilizes NO through inactivation of superoxide anion, augmented microglial-mediated neurotoxicity either alone or in combination with MK-801 or APV. Hence, immunostimulated microglia mediate neurotoxicity by NO, reactive nitrogen oxides, superoxide anion and NMDA-like substances. These findings suggest a novel role for microglial-produced NO and reactive nitrogen oxides as a neurotoxic agent in neurodegenerative disease states.


Asunto(s)
Neuroglía/metabolismo , Óxido Nítrico/metabolismo , Óxidos de Nitrógeno/metabolismo , Aminoácido Oxidorreductasas/metabolismo , Animales , Arginina/fisiología , Muerte Celular/fisiología , Células Cultivadas , Cerebelo/metabolismo , Citocinas/farmacología , Femenino , Inmunización , Inmunohistoquímica , Óxido Nítrico Sintasa , Nitritos/metabolismo , Embarazo , Ratas , Ratas Endogámicas , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/fisiología
13.
Int J Neurosci ; 65(1-4): 247-58, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1341687

RESUMEN

Strain differences in both immune function and behavior were observed following exposure of mice to the death of cage-cohorts. AKR/J, BALB/cN, and C3H/HeJ mice were exposed to a dead cohort for two hours at 48 hour intervals for 30 days. During this two hour period, AKR/J mice displayed intense fighting and mounting behavior. In addition, these mice attacked, cannibalized, and buried carcasses. Neither C3H/HeJ nor BALB/cN mice exhibited the complete repertoire of behaviors directed at either carcasses or cage-cohorts observed in AKR/J mice. After 15 exposures to the death of cage-cohorts, allogeneic cytotoxic T-lymphocyte (CTL) response was suppressed in AKR/J mice, but was enhanced or unchanged in C3H/HeJ and BALB/cN mice, respectively. Other immune parameters including natural killer (NK) cell activity, and lipopolysaccharide-stimulated B cell proliferation were unchanged in AKR/J mice but increased in BALB/cN mice exposed to the death of cage-cohorts for thirty days. These results suggest: 1) that both suppression of the CTL response and behaviors indicative of defensive burying in AKR/J mice may specifically be due to the loss of cage-cohorts, since they were not observed following exposure of these mice to the death of contraspecific animals; and 2) that both the behavioral repertoire and immune responses following exposure to the death of cage-cohorts may be strain dependent. This strain dependence may reflect differences in the ability to cope with the intermittent presentation of a stressor, and may explain, at least in part, variability in stress-induced changes in immune functions.


Asunto(s)
Nivel de Alerta/fisiología , Linfocitos B/inmunología , Citotoxicidad Inmunológica/inmunología , Miedo/fisiología , Células Asesinas Naturales/inmunología , Activación de Linfocitos/inmunología , Estrés Psicológico/complicaciones , Linfocitos T/inmunología , Conducta Agonística/fisiología , Animales , Tolerancia Inmunológica/inmunología , Masculino , Ratones , Ratones Endogámicos , Medio Social , Especificidad de la Especie , Estrés Psicológico/inmunología
14.
Ann N Y Acad Sci ; 650: 132-9, 1992 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-1318653

RESUMEN

The effects of alprazolam (ALP), a triazolobenzodiazepine with high affinity for "central" benzodiazepine receptors, were examined on several parameters of immune function in mice. NK, MLR, and mitogen-induced lymphocyte proliferation were all significantly increased 2 hr after administration of low doses (0.02-1.0 mg/kg) of ALP. Twenty four hr later, similar but less robust immunoenhancing effects were observed. These measures of immune functions were not affected by higher doses of ALP (5-10 mg/kg). The immunoenhancing effects of ALP did not appear related to serum corticosterone levels. These and other findings demonstrate that the GABA/benzodiazepine receptor chloride channel complex can bidirectionally modulate immune function.


Asunto(s)
Alprazolam/administración & dosificación , Inmunidad/efectos de los fármacos , Receptores de GABA-A/efectos de los fármacos , Animales , Citotoxicidad Inmunológica/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inmunidad Celular/efectos de los fármacos , Células Asesinas Naturales/inmunología , Activación de Linfocitos/efectos de los fármacos , Masculino , Ratones , Factores de Tiempo
15.
J Neuroimmunol ; 37(1-2): 131-40, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1548376

RESUMEN

Astrocyte-enriched primary glial cultures (AGC) from C57BL/6 mice were found to be highly susceptible to infection with the replication competent components of LP-BM5, consisting of the ecotropic and mink cell focus-inducing (MCF) helper murine leukemia viruses (MuLVs). The presence in infected AGC of defective LP-BM5 MuLV genome, a critical component for induction of the disease referred to as murine AIDS, was confirmed by Southern blot hybridization using a probe reactive with the p12 gag sequence of the 4.9 kb defective genome. Electron microscopic studies demonstrated C-type retrovirus particles in both astrocytes and microglial cells. In vivo studies demonstrated that the ecotropic MuLVs and the defective genome could be detected within AGC obtained form either 14-day-old mice following intraperitoneal inoculation or 7-day-old mice following intracranial inoculation. These findings suggest that: (1) the central nervous system (CNS) infection is present at an early stage in murine AIDS, (2) both astrocytes and microglial cells are possible CNS targets in which helper MuLVs replicate, and (3) these cells can harbor the defective genome that is a critical component for disease induction.


Asunto(s)
Encefalopatías/microbiología , Leucemia Experimental/microbiología , Virus Inductores de Focos en Células del Visón , Síndrome de Inmunodeficiencia Adquirida del Murino/microbiología , Animales , Astrocitos/microbiología , Células Cultivadas , Susceptibilidad a Enfermedades , Genoma Viral , Leucemia Experimental/genética , Ratones , Ratones Endogámicos C57BL , Neuroglía/microbiología , Neuroglía/patología , Neuroglía/fisiología
16.
Life Sci ; 50(6): 419-26, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1346466

RESUMEN

Ethanol inhibited the mitogen-induced initial increase in cytoplasmic free-calcium [Ca2+]i in mouse splenocytes. This effect was concentration-dependent, reversible, and observed at pharmacologically relevant concentrations (24-166mM). Other short-chain alcohols such as propanol, butanol, and pentanol also inhibited this mitogen-induced increase in [Ca2+]i. The potencies of these alcohols to produce this effect were highly correlated (r = 0.98, p less than 0.001) with their membrane/buffer partition coefficients. Analysis of mouse splenocyte subpopulations demonstrated that this effect was manifest in both B and T lymphocytes. Within T lymphocyte subpopulations, both CD4+ and CD8+ T cells were affected. These results suggest that the inhibition of [Ca2+]i increase may be an early event mediating ethanol-induced immunosuppression and that this may be a predisposing factor to infection and malignancies associated with alcoholism.


Asunto(s)
Linfocitos B/efectos de los fármacos , Calcio/metabolismo , Etanol/farmacología , Activación de Linfocitos/efectos de los fármacos , Bazo/inmunología , Linfocitos T/efectos de los fármacos , Alcoholismo/inmunología , Animales , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Concanavalina A/farmacología , Citometría de Flujo , Ratones , Ratones Endogámicos C57BL , Linfocitos T/inmunología , Linfocitos T/metabolismo
17.
J Neurochem ; 57(6): 2106-15, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1940917

RESUMEN

Elucidation of the mechanism(s) by which 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP) and its active metabolite 1-methyl-4-phenylpyridinium (MPP+) cause parkinsonism in humans and other primates has prompted consideration of possible endogenous MPTP/MPP(+)-like neurotoxins in the etiology of idiopathic Parkinson's disease. Here we examined inhibition of mitochondrial respiration in vitro and neurotoxicity in rats in vivo produced by beta-carbolinium compounds that are presumed to form following Pictet-Spengler cyclization of serotonin. We also evaluated N-methylisoquinolinium, a putative endogenous neurotoxin, in the same manner. The latter compound exhibited MPP(+)-like mitochondrial respiratory inhibition, whereas the beta-carbolinium compounds, although more potent inhibitors of electron transport, exhibited weak accumulation-dependent enhancement of inhibition in intact mitochondria. It is interesting that the beta-carbolinium compounds inhibited succinate- as well as glutamate-supported respiration, and are best described as inhibitor-uncouplers. The results of partitioning experiments suggest that both the low accumulation potential and the inhibition of succinate respiration may be a consequence of the beta-carboliniums being in equilibrium with neutral "anhydro" bases. Relative to MPP+, all compounds tested had weak dopaminergic uptake activity in vitro and weak dopaminergic toxicity in vivo, consistent with other findings of relatively low neurotoxic potential for presumed endogenous pyridiniums.


Asunto(s)
Dopamina/fisiología , Mitocondrias/efectos de los fármacos , Neurotoxinas/farmacología , Consumo de Oxígeno/efectos de los fármacos , Compuestos de Piridinio/farmacología , 1-Metil-4-fenilpiridinio/farmacología , Animales , Aniones , Mitocondrias/metabolismo , NAD/antagonistas & inhibidores , NAD/metabolismo , Oxidación-Reducción , Compuestos de Piridinio/química , Compuestos de Quinolinio/farmacología , Ratas , Succinatos/metabolismo , Ácido Succínico , Tetrafenilborato/farmacología
18.
FASEB J ; 5(8): 2194-9, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-2022315

RESUMEN

Morphine administered as a subcutaneous implant inhibits the initial increase in cytoplasmic free-calcium [Ca2+]i induced by mitogens in mouse splenocytes. This effect was not reproduced by incubation of splenocytes with morphine (10(-8)-10(-4) M). Analysis of splenocyte subpopulations demonstrates that this effect was manifest in both B and T cells. However, within T cell subpopulations, CD4+ but not CD8+ cells were affected. Adrenalectomy abolished this effect of morphine in CD4+ T but not CD4-, CD8- spleen cells (most likely Thy 1.2- B cells). Moreover, simultaneous administration of the opiate antagonist naltrexone blocked the effect of morphine in CD4-, CD8- spleen cells, but not in CD4+ T cells. These data indicate that the effects of morphine on mitogen-stimulated increase in [Ca2+]i may be mediated through distinct glucocorticoid-dependent and -independent mechanisms. The morphine-induced inhibition of an increase in [Ca2+]i in immune cells reported here may be an early event mediating opiate-induced immunosuppression.


Asunto(s)
Calcio/farmacocinética , Tolerancia Inmunológica/efectos de los fármacos , Narcóticos/farmacología , Animales , Transporte Biológico Activo/efectos de los fármacos , Concanavalina A/farmacología , Dexametasona/farmacología , Citometría de Flujo , Ratones , Ratones Endogámicos C57BL , Morfina/farmacología , Naltrexona/farmacología , Bazo/efectos de los fármacos , Bazo/inmunología , Bazo/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología
19.
Immunopharmacology ; 21(2): 91-7, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1652574

RESUMEN

A dose-dependent (12.5-100 mg/kg) suppression of cytotoxic T lymphocyte (CTL) activity was observed in mice after administration of the benzodiazepine receptor 'inverse agonist' FG 7142 (N-methyl-beta-carboline-3-carboxamide). This compound produces a syndrome resembling stress or anxiety in both animals and man. Addition of FG 7142 (1-1000 nM) to either a 4-hour 51Chromium-release assay or 5-day in vitro CTL generation system did not affect CTL activity. Pretreatment with the benzodiazepine receptor antagonist Ro 15-1788 (10 mg/kg) attenuated FG 7142-induced suppression of CTL activity, but had no effect when administered alone. Time-course studies indicated that FG 7142-induced suppression of CTL activity was long-lasting. The suppression of CTL activity by FG 7142 provides further evidence that the central nervous system pathways subserved by the benzodiazepine/GABA receptor chloride channel complex may play an important role in the modulation of immune function.


Asunto(s)
Carbolinas/farmacología , Linfocitos T Citotóxicos/efectos de los fármacos , Animales , Carbolinas/administración & dosificación , Relación Dosis-Respuesta a Droga , Flumazenil/farmacología , Inmunosupresores , Técnicas In Vitro , Cinética , Masculino , Ratones , Ratones Endogámicos , Receptores de GABA-A/efectos de los fármacos , Receptores de GABA-A/inmunología , Linfocitos T Citotóxicos/inmunología
20.
J Immunol Methods ; 137(2): 237-44, 1991 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-1672879

RESUMEN

A method is described for flow microfluorometric analysis of calcium mobilization in immune cells. This method is based on dual-color analysis of heterogeneous cell populations using fluo-3 and phycoerythrin (PE)-conjugated monoclonal antibody (mAb). This technique allows the detection of fluo-3 fluorescence as a measure of an increase in cytoplasmic free calcium ([Ca2+]i) while simultaneously discriminating PE-mAb-labeled cells without using wavelength ratio imaging. This method provides a unique way to distinguish patterns of calcium mobilization within a heterogeneous cell population.


Asunto(s)
Compuestos de Anilina , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/inmunología , Calcio/análisis , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Xantenos , Animales , Anticuerpos Monoclonales , Antígenos de Superficie/inmunología , Autoanticuerpos/farmacología , Complejo CD3 , Antígenos CD4/inmunología , Antígenos CD8 , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Mitógenos/farmacología , Ficoeritrina , Antígenos Thy-1
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