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1.
Rev Neurol (Paris) ; 177(8): 1001-1005, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33483091

RESUMEN

In stroke units, diagnosing seizures may be difficult, especially in aphasic patients. We discuss herein our systematic 4-hour video EEG monitoring of 61 patients with aphasia within the first 72hours after the onset of ischaemic stroke. Five electrographic seizures were identified in 3 patients, with no clinical signs apparent on the video and no symptoms reported by patients. We did not record status epilepticus nor generalized seizure. Comparative analyses disclosed a higher risk of early seizures in patients with haemorrhagic transformation. Video EEG monitoring detected electrographic seizures in 5% of stroke patients with aphasia. This monitoring could be useful for selected patients, especially those with haemorrhagic transformation.


Asunto(s)
Afasia , Isquemia Encefálica , Accidente Cerebrovascular , Afasia/diagnóstico , Afasia/etiología , Electroencefalografía , Humanos , Estudios Retrospectivos , Convulsiones/diagnóstico , Convulsiones/etiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico
2.
J Neurol ; 271(9): 6096-6101, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39046522

RESUMEN

In patients suffering from focal drug-resistant epilepsy, intracranial explorations are the gold standard for identifying the epileptogenic zone and evaluating the possibility of a surgical resection. Amongst them, stereoelectroencephalography (SEEG), using depth electrodes, is a safe procedure. However, complications occur on average in 2% of cases, notably haemorrhages or infections. Vasogenic cerebral oedema constitutes a rarely reported complication. Amongst the 85 patients explored with SEEG between January 2017 and September 2023, three had a clinically and electrophysiologically relevant vasogenic cerebral oedema. In these three patients, the surgical procedure was uneventful. In all three as well, electrodes exploring areas away from the epileptogenic zone recorded some unexpected focal delta slowing with clinically asymptomatic superimposed discharges, a pattern so far only reported in cases of bleeding. Moreover, one patient experienced confusion 10 days after explantation. Post-explantation magnetic resonance imaging showed, in all three patients, a vasogenic oedema that fully resolved a few months later. We did not identify any contributing factors, and there were no particularities concerning the number of electrodes, their implantation site or the recording duration. Focal delta slowing and rhythmic discharges during SEEG can indicate a vasogenic oedema. Clinical consequences can occur after explantation. Evolution is favourable but this misleading pattern must be identified.


Asunto(s)
Edema Encefálico , Epilepsia Refractaria , Electroencefalografía , Humanos , Edema Encefálico/etiología , Edema Encefálico/fisiopatología , Edema Encefálico/diagnóstico por imagen , Femenino , Masculino , Epilepsia Refractaria/fisiopatología , Epilepsia Refractaria/cirugía , Epilepsia Refractaria/diagnóstico , Adulto , Técnicas Estereotáxicas , Electrodos Implantados/efectos adversos , Persona de Mediana Edad
3.
Curr Health Sci J ; 45(3): 316-320, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32042461

RESUMEN

Acute pancreatitis is a pathological entity that poses numerous diagnostic and treatment problems. Severe form is a real challenge for a physician because it has multiple obscure causes, as well as a complex pathophysiology. Thus, the diagnosis is difficult and the choice of the right time for surgical treatment is controversial, the treatment being more frequently nonspecific, supportive for the various affected systems and organs. On a group of 337 patients, laboratory and imaging investigations were performed to diagnose and determine the severity score of acute pancreatitis and the correlation level between the neutrophil-lymphocytes ratio values and the Balthazar score, as a valid assessment method for local and systemic inflammatory changes. The distribution's study of acute pancreatitis by gender according to etiology confirms the predominance of the acute ethanolic pancreatitis in male, but also the higher proportion (54%) of male pancreatitis (181 man vs. 156 women) with gender ratio male/female 1.16/1. The neutrophil-lymphocytes ratio mean value varied according with the Balthazar severity score, that got higher as acute pancreatitis got more advanced and with a certain cut-off value can be considered a simple indicator to determine the severity of acute pancreatitis.

4.
Prog Lipid Res ; 40(6): 498-563, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11591437

RESUMEN

Since its discovery three decades ago, sterol carrier protein-2 (SCP-2) has remained a fascinating protein whose physiological function in lipid metabolism remains an enigma. Its multiple proposed functions arise from its complex gene structure, post-translational processing, intracellular localization, and ligand specificity. The SCP-2 gene has two initiation sites coding for proteins that share a common 13 kDa SCP-2 C-terminus: (1) One site codes for 58 kDa SCP-x which is partially post-translationally cleaved to 13 kDa SCP-2 and a 45 kDa protein. (2) A second site codes for 15 kDa pro-SCP-2 which is completely post-translationally cleaved to 13 kDa SCP-2. Very little is yet known regarding how the relative proportions of the two transcripts are regulated. Although all three proteins contain a C-terminal SKL peroxisomal targeting sequence, it is unclear why all three proteins are not exclusively localized in peroxisomes. However, the recent demonstration that the SCP-2 N-terminal presequence in pro-SCP-2 dramatically modulated the intracellular targeting coded by the C-terminal peroxisomal targeting sequence may account for the observation that as much as half of total SCP-2 is localized outside the peroxisome. The tertiary and secondary structure of the 13 kDa SCP-2, but not that of 15 kDa pro-SCP-2 and 58 kDa SCP-x, are now resolved. Increasing evidence suggests that the 58 kDa SCP-x and 45 kDa proteins are peroxisomal 3-ketoacyl-CoA-thiolases involved in the oxidation of branched chain fatty acids. Since 15 kDa pro-SCP-2 is post-translationally completely cleaved to 13 kDa SCP-2, relatively little attention has been focused on this protein. Finally, although the 13 kDa SCP-2 is the most studied of these proteins, because it exhibits diversity of its ligand partners (fatty acids, fatty acyl CoAs, cholesterol, phospholipids), new potential physiological function(s) are still being proposed and questions regarding potential compensation by other proteins with overlapping specificity are only beginning to be resolved.


Asunto(s)
Proteínas Portadoras/genética , Proteínas de Plantas , Regiones Promotoras Genéticas/genética , Acetil-CoA C-Acetiltransferasa/genética , Acetil-CoA C-Acetiltransferasa/metabolismo , Acilcoenzima A/metabolismo , Animales , Bilis/metabolismo , Ácidos y Sales Biliares/metabolismo , Sitios de Unión , Transporte Biológico , Proteínas Portadoras/metabolismo , Proteínas Portadoras/fisiología , Colesterol/metabolismo , Citosol/metabolismo , Ácidos Grasos/metabolismo , Humanos , Metabolismo de los Lípidos , Ratones , Ratones Transgénicos , Mitocondrias/metabolismo , Peroxisomas/metabolismo , Unión Proteica , Biosíntesis de Proteínas , Procesamiento Proteico-Postraduccional , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína
5.
Curr Health Sci J ; 41(1): 35-41, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-30151248

RESUMEN

Chronic Obstructive Pulmonary Disease (COPD) is a clinical syndrome characterised by a slow progressive decline in expiratory airflow [1], a process that has gradually developed over the years. Studies of patients with COPD show an inflammatory process in the small airways [2]. The aim of this paper is to identify the cytopathological aspects of the liquids present in the bronchoalveolar lavage in patients with COPD. We were performed a descriptive analytical case-control and prospective study on forty patients with COPD and ten asymptomatic smokers (healthy smokers or patients at risk). The percentage of marcophage, the type of the dominant inflamatory cell, in the bronchoalveolar lavage (BAL) liquid was significantly higher at patients with mild and moderate COPD as compared to patients with severe and very severe COPD. In the present work, the percentage of the neutrophil in the BAL liquid was significantly higher at patients with severe and very severe COPD, as compared to the patients with mild and moderate COPD and to aparently healthy smokers. In conclusion, we can say that COPD is characterized by an inflammatory process located in the small airways with predominant participation of macrophages, the procentage of macrophages in BAL fluid variyng inversely proportional to the severity of the disease.

6.
Protein Sci ; 7(6): 1396-403, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9655344

RESUMEN

The configurational distribution of phosphoglycerate kinase (PGK) strongly-denatured in 4 M guanidine hydrochloride solution is investigated using small-angle neutron scattering (SANS) and Monte Carlo computer simulation. It is shown that the experimental scattering profile can be represented by a random flexible chain of spheres of excess scattering density with excluded volume interactions, the best agreement being achieved when partial sphere intersection is allowed. The radius of gyration of the chain increases by a factor of 4 on denaturation, whereas the average length of segments approximately 5 residues long increases by only approximately 10%, consistent with a picture in which the large expansion on denaturation originates primarily from increased long-range flexibility of the polypeptide chain. The results provide a description of the chain statistics from which the construction of starting points for simulation studies of folding of the protein can be envisaged.


Asunto(s)
Fosfoglicerato Quinasa/química , Desnaturalización Proteica , Simulación por Computador , Guanidina , Matemática , Método de Montecarlo , Neutrones , Dispersión de Radiación , Soluciones
7.
Protein Sci ; 9(6): 1129-36, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10892806

RESUMEN

Understanding protein folding requires the determination of the configurational space accessible to the protein at different stages in folding. Here, computer simulation analysis of small angle neutron scattering results is used to probe the change in the distribution of configurations on strong denaturation of a globular protein, phosphoglycerate kinase, in 4 M guanidine hydrochloride solution. To do this atomic-detail ensembles of the unfolded protein chain are modeled and their scattering profiles compared with the experiment. The local conformational statistics are found to strongly influence the experimental intensity at scattering vectors between 0.05 and 0.3 A(-1). Denaturation leads to a reduction in the protein atom-pair distance distribution function over the approximately 3-15 A region that is associated with a quantifiable shift in the backbone torsional angle (phi, psi) distribution toward the beta region of the Ramachandran plot.


Asunto(s)
Pliegue de Proteína , Simulación por Computador , Modelos Moleculares , Conformación Proteica
8.
J Neuroimmunol ; 62(2): 127-35, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7499500

RESUMEN

Cloned cerebrovascular endothelial cells (CVE) persistently infected with Theiler's virus (PI-CVE) have been established and characterized. The CVE were derived from strains of mice that are susceptible (SJL/J and CBA) and resistant (BALB/c) to Theiler's virus-induced demyelination (TVID). The cells were persistently infected with either the BeAn or GDVII strains of Theiler's virus in vitro and studied at various passage levels for infectious virus, viral antigen and the expression of major histocompatibility complex (MHC) Class I and II antigens. The virus replicated to lower titers than in acutely infected CVE and appeared to be more cell-associated. Flow cytometric analysis revealed that 18-39% of the PI-CVE contained viral antigen. Persistently infected CVE derived from SJL/J and CBA mice expressed high levels of MHC Class I, whereas BALB/c PI-CVE did not. MHC Class II was upregulated by IFN-gamma in SJL/J PI-CVE albeit at a slightly lower level than in uninfected CVE. In addition, the PI-CVE demonstrated increased levels of mRNA for IL-1 beta when compared to uninfected CVE.


Asunto(s)
Encéfalo/irrigación sanguínea , Endotelio Vascular/virología , Poliomielitis/inmunología , Theilovirus , Animales , Antígenos Virales/análisis , Encéfalo/virología , Células Clonales , Endotelio Vascular/inmunología , Citometría de Flujo , Antígenos de Histocompatibilidad Clase I/análisis , Antígenos de Histocompatibilidad Clase II/análisis , Interleucina-1/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos CBA , Poliomielitis/virología , Theilovirus/inmunología , Theilovirus/aislamiento & purificación
9.
Immunol Lett ; 67(1): 15-22, 1999 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10217201

RESUMEN

Apoptosis of tumor cells and of apparently normal renal cells (ANRC) isolated from the same kidney in 42 untreated patients with renal carcinomas (RC) was evaluated. Thirty five of the investigated tumors were of Grawitz type in different grades of differentiation. The intensity of the apoptotic process was routinely assessed by propidium iodide staining and flow-cytometry analysis. Similar results were obtained in the same cases by using TUNEL assay, by staining with annexin V and by DNA electrophoresis. In 85% of Grawitz carcinomas the proportion of apoptotic tumor cells was quite high, with mean% +/- SD of 57.7+/-27.3, whereas in transitional cell carcinoma of the bladder (TCC), the mean percentage of cells in apoptosis was of 22.3+/-13.9. Unexpectedly, in ANRC displaying normal morphology and normal DNA content (diploidy), the mean% +/- SD of apoptotic cells were found to exceed that of apoptotic tumor cells, 79.2+/-21.6. The percentages of cells expressing Fas receptor and/or Fas ligand varied between large ranges in both tumor and ANRC, thus suggesting that other mechanisms are also involved in the activation of apoptosis. Immunohistochemical studies showed that the intensity of apoptosis correlated well with high p-53 and low bcl-2 expression. The intensity of apoptosis was generally not correlated with the cell proliferation index (S phase fraction), suggesting that in RC apoptosis can be activated in any stage of the cell cycle. Further investigations are necessary to understand the peculiar behaviour of tumor cells as well as of ANRC in renal carcinomas as compared to other types of malignancies.


Asunto(s)
Apoptosis , Neoplasias Renales/patología , Carcinoma de Células Transicionales/patología , Colorantes , Proteína Ligando Fas , Citometría de Flujo , Humanos , Etiquetado Corte-Fin in Situ , Neoplasias Renales/metabolismo , Glicoproteínas de Membrana/biosíntesis , Propidio , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Proteína p53 Supresora de Tumor/biosíntesis , Neoplasias de la Vejiga Urinaria/patología , Receptor fas/biosíntesis
10.
Viral Immunol ; 14(3): 251-62, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11572635

RESUMEN

In response to the 1996 West Nile (WN) fever epidemic that occurred in Bucharest and southeastern Romania, a surveillance program was established. The surveillance system detected 39 clinical human WN fever cases during the period 1997-2000: 14 cases in 1997, 5 cases in 1998, 7 cases in 1999, and 13 cases in 2000. Thirty-eight of the 39 case-patients lived in the greater Danube Valley of southern Romania, and 1 case-patient resided in the district of Vaslui, located on the Moldavian plateau. The estimated annual case incidence rate for the surveillance area during the period 1997-2000 was 0.95 cases per million residents. Thirty-four cases were serologically confirmed, and 5 cases were classified as probable. Twenty-four case-patients presented with clinical symptoms of meningitis (62%), 12 with meningoencephalitis (31%), 1 with encephalitis (3%), and 2 with febrile exanthema (5%). Five of the 39 cases were fatal (13%). Fourteen case-patients resided in rural areas, and 25 in urban and suburban areas, including 7 case-patients who resided in Bucharest. The ages of case-patients ranged from 8 to 76 years with a median age of 45 years. Twenty-four case-patients were males and 15 were females. Dates of onset of illness occurred from May 24 through September 25, with 82% of onset dates occurring in August and September. Limited entomological surveillance failed to detect WN virus. Retrospective sampling of domestic fowl in the vicinity of case-patient residences during the years 1997-2000 demonstrated seroprevalence rates of 7.8%-29%. Limited wild bird surveillance demonstrated seroprevalence rates of 5%-8%. The surveillance data suggest that WN virus persists focally for several years in poorly understood transmission cycles after sporadic introductions or that WN virus is introduced into Romania at relatively high rates, and persists seasonally in small foci.


Asunto(s)
Anticuerpos Antivirales/sangre , Vigilancia de Guardia , Fiebre del Nilo Occidental/epidemiología , Virus del Nilo Occidental/inmunología , Adolescente , Adulto , Anciano , Animales , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/virología , Aves/virología , Niño , Culex/virología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aves de Corral/virología , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/virología , Rumanía/epidemiología , Estudios Seroepidemiológicos , Fiebre del Nilo Occidental/transmisión , Fiebre del Nilo Occidental/veterinaria , Fiebre del Nilo Occidental/virología
11.
Leuk Lymphoma ; 34(5-6): 597-601, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10492085

RESUMEN

Angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is today recognized as a T-cell lymphoma which in most cases runs an aggressive course. The diagnosis is often difficult because of the varying clinico-pathological picture. Less than a third of the patients can be expected to have long-term remissions even after multiagent chemotherapy. Complete remissions have been reported after the use of interferon-alpha, cyclosporin A, and recently purine analogues in a few patients. We now report two cases of AILD that had unmaintained remissions for 32 and 10 months, respectively, after fludarabine therapy. In one of the patients fludarabine was used up-front and in the other after she had proved to be resistant to CHOP treatment. No severe infectious complications were noted. The use of purine analogues should be investigated further in AILD.


Asunto(s)
Antineoplásicos/uso terapéutico , Linfadenopatía Inmunoblástica/tratamiento farmacológico , Linfoma de Células T/tratamiento farmacológico , Vidarabina/análogos & derivados , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Linfadenopatía Inmunoblástica/patología , Linfoma de Células T/patología , Persona de Mediana Edad , Inducción de Remisión , Vidarabina/uso terapéutico
12.
Exp Biol Med (Maywood) ; 226(10): 873-90, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11682693

RESUMEN

Cellular cholesterol homeostasis is a balance of influx, catabolism and synthesis, and efflux. Unlike vascular lipoprotein cholesterol transport, intracellular cholesterol trafficking is only beginning to be resolved. Exogenous cholesterol and cholesterol ester enter cells via the low-density lipoprotein (LDL) receptor/lysosomal and less so by nonvesicular, high-density lipoprotein (HDL) receptor/caveolar pathways. However, the mechanism(s) whereby cholesterol enters the lysosomal membrane, translocates, and transfers out of the lysosome to the cell interior are unknown. Likewise, the steps whereby cholesterol enters the cytofacial leaflet of the plasma membrane caveolae, rapidly translocates, leaves the exofacial leaflet, and transfers to extracellular HDL are unclear. Increasing evidence obtained with model and isolated cell membranes, transfected cells, genetic mutants, and gene-ablated mice suggests that proteins such as caveolin, sterol carrier protein-2 (SCP-2), Niemann-Pick C1 protein, steroidogenic acute regulatory protein (StAR), and other intracellular proteins mediate intracellular cholesterol transfer. While these proteins bind cholesterol and/or interact with cholesterol-rich membrane microdomains (e.g., caveolae, rafts, and annuli), their relative contributions to direct molecular versus vesicular cholesterol transfer remain to be resolved. The formation, regulation, and role of membrane microdomains in regulating cholesterol uptake/efflux and trafficking are unclear. Some cholesterol-binding proteins exert opposing effects on cellular cholesterol uptake/efflux, transfer of cholesterol out of the lysosomal membrane, and/or intracellular cholesterol trafficking to select membranous organelles. Resolving these cholesterol pathways and the role of membrane cholesterol microdomains is essential to our understanding not only of processes that affect cholesterol metabolism, but also of the abnormal regulation that may lead to disease (diabetes, obesity, atherosclerosis, neutral lipid storage, Niemann-Pick C, congenital lipoid adrenal hyperplasia, etc.).


Asunto(s)
Estructuras de la Membrana Celular/metabolismo , Membrana Celular/metabolismo , Colesterol/metabolismo , Proteínas de Plantas , Proteínas/metabolismo , Animales , Transporte Biológico , Proteínas Portadoras/metabolismo , Caveolas , Membrana Celular/ultraestructura , Estructuras de la Membrana Celular/química , Retículo Endoplásmico/metabolismo , Aparato de Golgi/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Lisosomas/metabolismo , Glicoproteínas de Membrana/metabolismo , Mitocondrias/metabolismo , Proteína Niemann-Pick C1
13.
Adv Space Res ; 1(14): 179-85, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-11541708

RESUMEN

Rats on board the Soviet Cosmos 936 satellite for l8 1/2 days showed a decreased glycoprotein secretion from the salivary mucous glands, stomach and intestine, and an increased leucine aminopeptidase and acid phosphatase content from the small intestine. Grimelius positive cells were activated. One group of rats were centrifuged at 1 g during the flight to simulate terrestrial gravity. Some investigations have suggested that under these conditions muscular and cardiac disorders diminished. In the digestive tract the benefits of centrifugation at 1 g are minimal and limited to a few glycoprotein components. The digestive changes are probably the expression of a stress response, unrelated to weightlessness. Similar changes, concomitant with a glycocorticoid hypersecretion, were found in rats after 15 days of hypokinesia on Earth. These digestive changes persisted even in adrenalectomized rats.


Asunto(s)
Sistema Digestivo/enzimología , Sistema Digestivo/metabolismo , Vuelo Espacial , Simulación de Ingravidez/efectos adversos , Ingravidez/efectos adversos , Fosfatasa Ácida/metabolismo , Animales , Centrifugación , Corticosterona/sangre , Corticosterona/metabolismo , Glicoproteínas/metabolismo , Hipocinesia , Inmovilización , Leucil Aminopeptidasa/metabolismo , Masculino , Ratas , Ratas Wistar , Glándulas Salivales/metabolismo , Estrés Fisiológico/enzimología , Estrés Fisiológico/etiología , Estrés Fisiológico/metabolismo
14.
Acta Virol ; 28(5): 362-8, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6151349

RESUMEN

As evaluated by light scattering at 90 degrees, natural organic oligocations such as putrescine, spermidine and spermine interfered with myxovirus aggregates which were induced by the histone H2A and strongly amplified by shaking during incubation. In contrast, the synthetic oligocation 1.7-diamino heptane itself aggregated the virus particles, its action being unmodified by adding polycationic H2A in abundance. When human chromosome preparations treated with protamine solution and shaked during incubation were covered with a stable polycationic molecular layer, the chromosomes had become unstainable by the Giemsa method even if the dye was used in excess. Nevertheless, the affinity of influenza virus particles for protamine was so high that they were able to dissociate the protamine molecules from the preformed complexes reconstituting the affinity of chromosome preparations to Giemsa stain. The virus-caused shift in the staining ability of chromosomes did not occur when bacterial suspension was added instead of the viral one. The model of oligocationic relaxation and of polycation condensation accounting for the modulatory effects of polyamines is discussed.


Asunto(s)
Cationes/farmacología , Virus de la Influenza A/efectos de los fármacos , Virus de la Parainfluenza 1 Humana/efectos de los fármacos , Cromosomas/fisiología , Histonas/farmacología , Luz , Poliaminas/farmacología , Polielectrolitos , Polímeros/farmacología , Dispersión de Radiación
15.
Aviat Space Environ Med ; 46(7): 916-21, 1975 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-168856

RESUMEN

The present paper refers to the activity of some enzymes associated with the cellular cytomembranes in the plasma and brain of guinea pigs exposed to the action of repeated +10Gz acceleration. Immediately after the last run, diminution of enzymatic activity in the brain supernate ran parralel to a rise in plasma enzymatic activity. Variations in enzymatic activity suggested the liberation of enzymes connected with the neuronal organelles, perhaps consequent to alterations in the permeability or structure of the neuronal cytomembranes. These alterations might also be interpreted as being accompanied by permeabilization of the blood-brain barrier, with release of enzymes from the neuronal structures into the plasma. Changes in the permeability of the neuronal membranes might be attributed to several factors: cerebral hypoxia following the hemodynamic and ventilation alterations induced by hypergravitation, the influence upon the membrane permeability of hormones released in excess under the stress of acceleration, and the strain to which the central nervous system neurones are subjected by the multitude of afferent impulses with a starting point in the various types of receptors stimulated by hypergravitation.


Asunto(s)
Aceleración , Encéfalo/enzimología , Glucosafosfato Deshidrogenasa/metabolismo , Gravitación , L-Lactato Deshidrogenasa/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Fosfatasa Ácida/sangre , Fosfatasa Ácida/metabolismo , Fosfatasa Alcalina/sangre , Fosfatasa Alcalina/metabolismo , Animales , Química Encefálica , Corteza Cerebral/citología , Glucosafosfato Deshidrogenasa/sangre , Cobayas , L-Lactato Deshidrogenasa/sangre , Masculino , Microscopía Electrónica , Neuronas/ultraestructura , Proteínas/análisis
16.
Roum Arch Microbiol Immunol ; 54(4): 295-311, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8993123

RESUMEN

Several variants of reagents were prepared by coupling type (I, II III, IV, V and VI) and group (3, 4, 6 and 7, 8, 9) anti-Shigella flexneri sera with protein A--containing staphylococcal suspension. For most serum lots coagglutination led to a 1/10 minimum dilution. However, different efficiencies were reported between serum lots and even within the same type or group. No improvement by the coagglutination reaction could be obtained for one lot from group 3, 4 and 7, 8, 9 sera and for both type IV serum lots. The coagglutination reactions were specific both with collection strains and with recently isolated strains and the two staphylococcal suspension lots showed an identical behaviour. Coagglutination may be used for obtaining a better efficiency of type and group. Shigella flexneri sera but this varies in terms of the serum lot and the serum/Staphylococcus combination used.


Asunto(s)
Aglutinación/inmunología , Técnicas de Laboratorio Clínico/métodos , Shigella flexneri/inmunología , Disentería Bacilar/sangre , Disentería Bacilar/diagnóstico , Sensibilidad y Especificidad , Shigella flexneri/aislamiento & purificación , Proteína Estafilocócica A/inmunología
17.
Roum Arch Microbiol Immunol ; 55(3): 225-39, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9256024

RESUMEN

It was proved spectrophotometrically that Mycoplasma agalactiae antigen inoculated in vivo in sheep modifies the corresponding erythrocyte lysates reactivity toward methylene blue and neutral red and induces several types of chromosomal rearrangements. The treatment in vivo of sheep with an original preparation obtained from the Phaseolus vulgaris pods restores the erythrocyte lysates reactivity toward the two redox dyes and reduces the chromosomal abnormalities frequency induced by the mycoplasmal antigen. It was also demonstrated by optical and electronical microscopy that the Smise line mouse meiocytes exhibit chromosomal abnormalities induced by the cyclophosphamide treatment in vivo. In the case of concomitant treatment with the cyclophosphamide and C vitamin the same frequency of abnormalities was recorded as in the simple treatment with the drug.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Antígenos Bacterianos/farmacología , Antioxidantes/farmacología , Ciclofosfamida/farmacología , Eritrocitos/efectos de los fármacos , Inhibidores de Crecimiento/farmacología , Mycoplasma/inmunología , Espermatocitos/efectos de los fármacos , Animales , Antígenos Bacterianos/administración & dosificación , Ácido Ascórbico/farmacología , Aberraciones Cromosómicas , Bandeo Cromosómico , Colorantes , Masculino , Meiosis/efectos de los fármacos , Azul de Metileno , Ratones , Rojo Neutro , Oxidación-Reducción , Fitohemaglutininas/farmacología , Ovinos , Vitamina A/farmacología , Vitamina E/farmacología
18.
Rom J Morphol Embryol ; 42(3-4): 203-12, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9168670

RESUMEN

A 34-year old woman was admitted for bilateral flank pain, maleolary and palpebral oedema with an insidious evolution lasting for 5 years. Urogram showed a left ureteral duplicity and a right lacunary pelvic image. MRI and echography indicated the complete modification as a renal structure as well as the presence of some bilateral tumoral formations with a nonhomogenous structure, blood diffusion and adenopathy of the renal hilum. Nephrectomy revealed white-gray tumoral nodular tumours. The histopathological test evidenced proliferations of leiomyofibromatous, angiomatous, lipomatous, cartilaginous types with a benign aspect suggesting the diagnosis of a renal dysembryoplasic tumor (hamartoma).


Asunto(s)
Hamartoma/patología , Enfermedades Renales/patología , Esclerosis Tuberosa/patología , Adulto , Femenino , Hamartoma/complicaciones , Humanos , Enfermedades Renales/complicaciones , Esclerosis Tuberosa/complicaciones
19.
Philos Trans R Soc Lond B Biol Sci ; 368(1621): 20130116, 2013 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-23713116

RESUMEN

The demand for more food is increasing fertilizer and land use, and the demand for more energy is increasing fossil fuel combustion, leading to enhanced losses of reactive nitrogen (Nr) to the environment. Many thresholds for human and ecosystem health have been exceeded owing to Nr pollution, including those for drinking water (nitrates), air quality (smog, particulate matter, ground-level ozone), freshwater eutrophication, biodiversity loss, stratospheric ozone depletion, climate change and coastal ecosystems (dead zones). Each of these environmental effects can be magnified by the 'nitrogen cascade': a single atom of Nr can trigger a cascade of negative environmental impacts in sequence. Here, we provide an overview of the impact of Nr on the environment and human health, including an assessment of the magnitude of different environmental problems, and the relative importance of Nr as a contributor to each problem. In some cases, Nr loss to the environment is the key driver of effects (e.g. terrestrial and coastal eutrophication, nitrous oxide emissions), whereas in some other situations nitrogen represents a key contributor exacerbating a wider problem (e.g. freshwater pollution, biodiversity loss). In this way, the central role of nitrogen can remain hidden, even though it actually underpins many trans-boundary pollution problems.


Asunto(s)
Cambio Climático , Ecosistema , Contaminantes Ambientales/efectos adversos , Contaminantes Ambientales/análisis , Actividades Humanas , Ciclo del Nitrógeno , Biodiversidad , Abastecimiento de Alimentos/normas , Combustibles Fósiles/análisis , Humanos
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