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1.
J Assist Reprod Genet ; 29(2): 131-5, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22116647

RESUMO

BACKGROUND: To analyze the effects of embryo transfer (ET) quality on clinical pregnancy (CPR) and live birth delivery rates (LBDR). METHODS: In a retrospective study at a single, private infertility center between November 2005 and December 2009 one thousand fifty-five day-3 and day-5 ETs following IVF/ICSI/IMSI were evaluated. We analyzed the impact of an atraumatic ET with a soft catheter (ET 1), after external guidance (ET 2), after probing of the cervix with a stylet (ET 3), or after grasping the portio vaginalis with a tenaculum (ET 4) on CPR and LBDR. RESULTS: The use of external guidance showed a significantly reduced LBDR as compared to an atraumatic ET (26.0% vs. 32.5%). The lowest CPR and LBDR were found in ET 4. The application of stylets in cases of difficult ETs was superior to the use of external guidance. No differences in miscarriages between ET 1-4 were noted. CONCLUSIONS: Besides embryo culture and patient history, the quality of an ET might also have an important impact on pregnancy outcome. Techniques to ensure an atraumatic ET, such as mechanic uterine cavity length measurements, before starting treatment might help identify patients at risk for a difficult ET and lead to modified treatments, such as the primary use of a stylet. Limitation of study: retrospective analysis.


Assuntos
Transferência Embrionária/normas , Fertilização in vitro , Nascido Vivo , Aborto Espontâneo , Adulto , Coeficiente de Natalidade , Transferência Embrionária/métodos , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas/métodos
2.
Cell Death Differ ; 23(2): 270-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26184909

RESUMO

Ferroptosis is a form of regulated non-apoptotic cell death that has been implicated in several disease contexts. A better understanding of the ferroptotic death mechanism could lead to the development of new therapeutics for degenerative diseases, and a better understanding of how to induce ferroptosis in specific tumor contexts. We performed an unbiased genome-wide siRNA screen to find genetic suppressors of ferroptosis. We determined that loss of CARS, the cysteinyl-tRNA synthetase, suppresses ferroptosis induced by erastin, which inhibits the cystine-glutamate antiporter known as system xc(-). Knockdown of CARS inhibited erastin-induced death by preventing the induction of lipid reactive oxygen species, without altering iron homeostasis. Knockdown of CARS led to the accumulation of cystathionine, a metabolite on the transsulfuration pathway, and upregulated genes associated with serine biosynthesis and transsulfuration. In addition, inhibition of the transsulfuration pathway resensitized cells to erastin, even after CARS knockdown. These studies demonstrate a new mechanism of resistance to ferroptosis and may lead to strategies for inducing and suppressing ferroptosis in diverse contexts.


Assuntos
Aminoacil-tRNA Sintetases/genética , Apoptose , Aminoacil-tRNA Sintetases/metabolismo , Animais , Antineoplásicos/farmacologia , Vias Biossintéticas , Cistina/metabolismo , Resistencia a Medicamentos Antineoplásicos , Técnicas de Silenciamento de Genes , Ácido Glutâmico/farmacologia , Humanos , Células PC12 , Piperazinas/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Serina/biossíntese , Transdução de Sinais
3.
J Am Coll Cardiol ; 14(6): 1491-500, 1989 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-2809009

RESUMO

The purpose of this study was to critically evaluate the usefulness of postexercise regional myocardial thallium-201 clearance for identifying disease in individual coronary arteries. Exercise and redistribution planar imaging studies were performed in 114 subjects, including 19 normal volunteers and 95 patients undergoing cardiac catheterization (70 with and 25 without greater than or equal to 50% narrowing in one or more coronary arteries). Thallium clearance was measured from predefined myocardial regions corresponding to the left anterior descending, left circumflex and right coronary arteries and was expressed as the percent decrease in activity at 4 h, assuming monoexponential clearance. In regions perfused by a normal or insignificantly diseased coronary artery, mean 4 h clearance was 58.9 +/- 9.4% for normal volunteers, 43.1 +/- 15.5% for catheterized patients without coronary artery disease and 36.3 +/- 24.9% for catheterized patients with coronary artery disease (p less than 0.001 patients with coronary artery disease versus normal volunteers). Clearance from normal regions was significantly associated with two measures of exercise performance: percent of predicted maximal heart rate achieved (r = 0.49) and exercise duration (r = 0.35). In regions perfused by a stenotic coronary artery, mean clearance was lower (31.1 +/- 19.8%) but was not significantly different from that in normal regions in the same patients. Clearance from diseased regions was also associated with maximal exercise heart rate (r = 0.28) and exercise duration (r = 0.41), but not with percent coronary artery stenosis (r = 0.02). After taking exercise performance into account, the number of diseased vessels or the presence or absence of disease in a given vessel had little influence on regional thallium clearance. Although measurement of regional post-exercise thallium clearance may help to identify stenotic coronary arteries in selected patients, variability related to exercise performance and other physiologic and technical factors greatly limits the clinical usefulness of absolute thallium clearance measurements.


Assuntos
Doença das Coronárias/metabolismo , Vasos Coronários/metabolismo , Radioisótopos de Tálio/metabolismo , Adulto , Idoso , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Exercício Físico , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia
4.
J Nucl Med ; 23(9): 781-5, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7108624

RESUMO

Using a method for determination of absolute volumes, including correcting for attenuation, we have explored the ability of the method to determine stroke volume in humans by radionuclide techniques. Thermodilution cardiac output determinations and multigated equilibrium blood-pool scintigraphy in the LAO view were performed simultaneously in twenty patients in which no evidence of intracardiac shunts or valvular disease was present. The correlation was good between the attenuated radionuclide and thermodilution stroke volume (r = 0.80, s.e.e. of estimate = 12 ml; SVtd = 2.31 x SVr + 18 ml). When correction for attenuation was made, the correlation improved (r = 0.96, s.e.e. = 6 ml) and approached the line of identity (SVtd = 0.99 x SVr + 1.2 ml). The correlation was also good between radionuclide cardiac output, corrected for attenuation, and the thermodilution cardiac output (r = 0.89, s.e.e. = 0.36 l/min; COtd = 0.86 x COr + 0.67 l/min). Thus our method of correction for attenuation in the determination of absolute left-ventricular volumes has been shown to provide a reliable, noninvasive means of calculating stroke volume and cardiac output in humans, without the use of geometric assumptions or regression equations.


Assuntos
Débito Cardíaco , Coração/diagnóstico por imagem , Volume Sistólico , Eritrócitos , Humanos , Métodos , Cintilografia , Tecnécio , Termodiluição
5.
Chest ; 94(2): 366-70, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3396416

RESUMO

Since asbestos burden in the lung can very among areas, the usefulness of small tissue samples for identifying past occupational exposure is examined. Simulated transbronchial biopsy samples and open lung biopsy samples were collected from autopsy material from 12 former amosite asbestos workers and ten persons from the general population. Tissue evaluation included (1) paraffin embedment and light microscopy screening for fibrosis and ferruginous bodies, and (2) tissue digestion, which was analyzed by the combination of (A) light microscopy screening for ferruginous bodies and (B) electron microscopy (EM) screening for uncoated fibers. Using standard pathology techniques to classify the small samples was generally unsuccessful, the samples being too small or their size compounding other random sampling problems. The most reliable method of establishing which transbronchial biopsy tissue samples were from the occupationally exposed group occurred when light and EM analyses were used to evaluate digested tissue. The combined data from the EM analysis of two samples per subject indicated controls had two or fewer observed asbestos fibers, while the amosite asbestos workers had six or more fibers. This distinction was valid even in those who, 21 years before sampling, had worked for only a few weeks in the asbestos plant.


Assuntos
Amianto/efeitos adversos , Biópsia/métodos , Pulmão/ultraestrutura , Doenças Profissionais/patologia , Fibrose Pulmonar/patologia , Adulto , Idoso , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Fibrose Pulmonar/etiologia
6.
Arch Pathol Lab Med ; 109(9): 849-52, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3839658

RESUMO

Tissue from a lung biopsy specimen was submitted for electron microscopy and x-ray energy-dispersive analysis of ferruginous bodies. The presence of these entities had been used as a factor in concluding an asbestos-related tissue response. A 62-year-old man had worked for over 25 years in an iron reclamation and manufacturing facility that had no known sources of asbestos in the work environment. He had no history of recurrent respiratory problems. Combined studies in tissue sections as well as on digested specimens revealed that the core of a majority of the ferruginous bodies was an iron-rich fiber. The source of the fibers was traced to a material used in packing and insulation of the metal during the tempering process. While there is a widespread regional potential for exposure in both environmental and occupational settings, the question as to whether the dust is actually a health hazard or more of a nuisance pollutant remains unanswered. It is evident, however, that the fibrous mineral should be recognized as a stimulus for ferruginous body formation in humans.


Assuntos
Asbestose/patologia , Ferro/metabolismo , Pulmão/patologia , Microanálise por Sonda Eletrônica , Humanos , Pulmão/metabolismo , Pulmão/ultraestrutura , Masculino , Metalurgia , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Doenças Profissionais/metabolismo , Doenças Profissionais/patologia
7.
J Burn Care Rehabil ; 12(2): 136-9, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2050720

RESUMO

Exposure of skin to liquid propane causes a severe freeze injury. This cutaneous injury has the appearance of a partial-thickness thermal injury of indeterminate depth, but the deep tissue damage is greater than is at first apparent. A case history is presented that illustrates the severity of this particular mechanism of injury and the need for adequate safety precautions.


Assuntos
Queimaduras Químicas/etiologia , Propano/efeitos adversos , Acidentes de Trabalho/prevenção & controle , Acidentes de Trabalho/estatística & dados numéricos , Amputação Cirúrgica , Queimaduras Químicas/patologia , Desbridamento , Congelamento , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Transplante de Pele
8.
J Burn Care Rehabil ; 12(6): 516-20, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1779004

RESUMO

Liquid propane causes a severe, deep thermal injury in unprotected tissue. Delayed surgical intervention, as for thermal burns, has been the gold standard of treatment. An animal model of liquid-propane injury was devised to document injury, to demonstrate a better method of protection, and to define an appropriate management protocol. Twenty-eight rats were classified into four groups: unprotected tissue (n = 8), skin covered with wool (n = 8), skin covered with Neoprene (Wm. H. Horn & Brothers Inc., Philadelphia, Pa.) (n = 8), and skin covered with wool plus Neoprene (n = 4). Each group was subdivided into two exposure times: 6 seconds and 30 seconds. The mean temperatures +/- standard error of the mean of the various tissue levels initially and at 6 and 30 seconds of exposure were determined. Histologic examination demonstrated that full-thickness tissue necrosis occurred in unprotected and wool-covered tissue. Areas that were covered with Neoprene showed intact skin and subcutaneous tissue with underlying muscle necrosis. Examination of the tissue that was covered with wool plus Neoprene showed no histologic damage. There was no sign of tissue regeneration at the wound periphery, and there was no histologic difference in any group, whether the examination took place at 1 or 5 days after injury. This study demonstrated that the best form of protection appears to be a wool glove liner covered with a Neoprene glove. The histologic evidence suggests that a liquid-propane injury to unprotected tissue should be managed aggressively with early excision and grafting.


Assuntos
Congelamento das Extremidades/induzido quimicamente , Propano , Roupa de Proteção , Animais , Congelamento , Congelamento das Extremidades/prevenção & controle , Congelamento das Extremidades/cirurgia , Membro Posterior/lesões , Masculino , Neopreno , Ratos , Ratos Endogâmicos ,
9.
Can J Vet Res ; 63(4): 288-91, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10534010

RESUMO

The effect of longeing and glucosamine supplementation on known biological markers of joint disease was studied in yearling quarter horses. Twenty-one yearling quarter horses were randomly assigned to one of 4 treatments: 1) longeing (longeing 20 min daily) supplement control (LN); 2) longeing/glucosamine (LG); 3) walking (mechanical walker for 120 min daily (WN)); and 4) walking/glucosamine (WG). Oral glucosamine was administered at 5.5 g b.i.d. weeks 1-4, 3.5 g b.i.d. during weeks 5-6, and 2.0 g b.i.d. during weeks 7-8. Serum was obtained weekly for 8 wk and analyzed for keratan sulfate and osteocalcin concentrations. Walked horses receiving glucosamine showed slight elevation in serum keratan sulfate compared to controls (P = 0.04). Glucosamine or longeing exercise had no significant effect (6 > or = 0.08) on serum osteocalcin concentrations. Under these conditions, longeing and/or glucosamine supplementation did not significantly alter serum concentrations of keratan sulfate or osteocalcin.


Assuntos
Glucosamina/farmacologia , Doenças dos Cavalos/prevenção & controle , Artropatias/veterinária , Condicionamento Físico Animal , Animais , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Glucosamina/administração & dosagem , Doenças dos Cavalos/fisiopatologia , Cavalos , Artropatias/fisiopatologia , Artropatias/prevenção & controle , Masculino
10.
Arch Environ Health ; 51(6): 462-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9012326

RESUMO

Tissue was obtained from two American groups. The tissue was defined by ferruginous body levels of either < or = 1000 or > 1000 ferruginous bodies/g dry weight, and tissue was evaluated by light microscopy and analyzed by analytical transmission electron microscopy. Tissue was bleach digested, and uncoated asbestos fibers were classified with respect to type and size. In addition, some ferruginous body cores were analyzed. There was a wide range of uncoated fibers associated with each ferruginous body. A relationship was found between amosite fibers and ferruginous bodies. Other asbestos types were not associated significantly with the development of ferruginous bodies. Uncoated crocidolite fibers were not detected in these samples; this result further emphasizes the under-appreciated exposure of Americans to amosite. The levels of ferruginous bodies in both groups suggest exposures above those expected in the general population. Uncoated chrysotile levels were below the ranges reported previously for some general populations. The data suggest that there is a wide variation in the ratio of uncoated to coated fibers and that the amphibole in the United States is more likely to be amosite than crocidolite.


Assuntos
Amianto/isolamento & purificação , Pneumopatias/etiologia , Exposição Ocupacional/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Fibras Minerais/classificação , Fumar , Estados Unidos
11.
Arch Environ Health ; 50(6): 462-5, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8572726

RESUMO

A 59-year-old man was exposed to chrysotile asbestos while rebuilding clutches. Analytical electron microscopy showed a chrysotile core in 72% of the ferruginous bodies from lung tissue. Long, uncoated chrysotile fibers were also present. Sufficient exposure to long chrysotile in jobs such as this appears to allow the majority of ferruginous bodies to be formed on chrysotile, an exception to the rule that most ferruginous bodies form on amphibole cores.


Assuntos
Asbestos Serpentinas/análise , Pneumopatias/patologia , Pulmão/química , Líquido da Lavagem Broncoalveolar/química , Carcinoma de Células Pequenas/diagnóstico , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Testes de Função Respiratória
12.
Geburtshilfe Frauenheilkd ; 74(10): 928-932, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25364032

RESUMO

Introduction: Diminished ovarian reserve (DOR) has been linked to certain subpopulations and distinct gene polymorphisms. It has even been hypothesized that the AB0 blood group system could be linked to ovarian reserve (OR) as reflected by early follicular phase follicle stimulating hormone (FSH) levels. Although estimation of OR is routinely done using levels of anti-Müllerian hormone (AMH), FSH, estradiol or inhibin B, the diagnostic accuracy of these markers is often limited. The aim of this study was to evaluate whether there is any correlation between IVF patients' AB0 blood group system and ART outcome. Methods: In this retrospective observational single-center study we investigated the outcome of 1889 IVF cycles carried out between 2005 and 2012 with regard to blood type and OR in different age groups (21-36 years and 37-43 years). The number of cumulus oocyte complexes (COCs) and metaphase II oocytes obtained after ovarian stimulation, fertilization rate (FR), pregnancy rate (PR) and birth rate (BR) were evaluated with respect to maternal age (21-36 and 37-43 years, respectively). Results: We found no significant differences in the average number of COCs after ovum pick-up in either of the age groups. Moreover, the mean number of MII oocytes and 2PN stages were similar for all blood type groups. As regards IVF outcome measured in terms of PR and BR, no significant differences were observed between the different blood groups. In conclusion, no correlation was found between blood type and female fertility. Discussion: The most precise definition of OR is determining the number of competent oocytes. Based on the finding of our study, the hypothesis that there is a correlation between OR and AB0 blood group system can be dismissed for Caucasian IVF patients.

14.
Breast J ; 7(6): 427-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11843856

RESUMO

The goal of screening mammograms is to provide early detection of breast cancer. As mammography technology improves, the ability to detect smaller and smaller suspicious lesions is increased. However, as mammography cannot always differentiate between malignant and benign lesions, biopsies are often needed. With the decreasing size of lesions seen on mammography, the size of the biopsy specimen needed for diagnosis also decreases. Thus, a smaller amount of normal breast tissue needs to be removed during a biopsy. For a majority of the small lesions, excision with a small margin of normal breast tissue is sufficient for diagnosis. The SiteSelect procedure utilizes stereotactic guidance to excise completely a tumor that is noted on a mammogram. The procedure can be performed under local anesthesia through a minimal incision (usually 1.5 cm). The SiteSelect biopsy procedure completely excises small tumors noted on the mammogram with minimal trauma to the breast tissue and with excellent cosmetic results. It is well tolerated by patients. For tumors requiring only local excision, such as atypical ductal hyperplasia or lobular carcinoma in situ, the SiteSelect procedure may be the only diagnostic procedure required.


Assuntos
Biópsia/métodos , Neoplasias da Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Técnicas Estereotáxicas
15.
Ann Pharmacother ; 26(12): 1530-4, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1482811

RESUMO

OBJECTIVE: To review current information relevant to the use of aspirin for preventing vascular death in women, and to provide recommendations based on this information. DATA SOURCES: References from pertinent articles are identified throughout the text. DATA SYNTHESIS: Based on current information, low-dose aspirin is not recommended as primary prevention for cardiovascular death in women; efforts are better focused at promoting risk-factor reduction. Low-dose aspirin is recommended for reducing further cardiovascular morbidity and mortality in women with known cardiovascular disease. Women presenting with unstable angina or myocardial infarction should receive aspirin 325 mg as soon as the diagnosis is confirmed, and this dosage should be continued on a chronic basis. Women who have experienced transient ischemic attacks or ischemic stroke should receive aspirin 1000 mg/d, with a subsequent dosage reduction to 325 mg/d in patients who do not tolerate the higher dose. CONCLUSIONS: Current recommendations are based on the results of studies that involved few women. Further investigation of antiplatelet agents for primary and secondary prevention of vascular death in women is needed.


Assuntos
Aspirina/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Transtornos Cerebrovasculares/prevenção & controle , Angina Instável/tratamento farmacológico , Angina Instável/mortalidade , Aspirina/efeitos adversos , Aspirina/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/mortalidade , Transtornos Cerebrovasculares/tratamento farmacológico , Transtornos Cerebrovasculares/mortalidade , Feminino , Humanos , Fatores de Risco
16.
Mod Pathol ; 2(4): 320-2, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2548182

RESUMO

Ferruginous bodies (FB) in sputa are recognized as an indicator of past exposure to asbestos. However, a great variability exists in FB production, even in individuals with a history of occupational exposure. A further complication in interpreting the presence of FBs in sputa is that all individuals in modern society are exposed to asbestos and, in lung tissue studies, have been shown to harbor appreciable numbers of asbestos fibers. Thus, some of these individuals should occasionally produce FBs in their sputa. The present study was undertaken to determine if uncoated asbestos fiber content could be used to better discriminate occupationally exposed individuals from the general population. Randomly selected sputum samples from 12 former workers in an amosite asbestos plant and 12 controls were studied. The samples were prepared for the study by digesting the sputa in sodium hypochlorite. The digests were filtered through 0.2-microns polycarbonate filters for collection of particulates. The filters were screened for FBs by light microscopy at 200 X, and the presence or absence of uncoated asbestos fibers was determined at 5000 X in an AMRAY 1000A scanning electron microscope. The use of electron microscopy revealed the presence of commercial amphiboles in the sputa of the occupationally exposed individuals and enabled a differentiation of these samples from those of the general population.


Assuntos
Amianto/análise , Metaloproteínas/análise , Escarro/análise , Adulto , Idoso , Amiantos Anfibólicos , Biomarcadores/análise , Exposição Ambiental , Feminino , Humanos , Masculino , Microscopia , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Distribuição Aleatória , Dióxido de Silício/análise
17.
Environ Res ; 43(1): 97-103, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2884098

RESUMO

Some of the widely used techniques employed in assessing asbestos load in lung tissue include the use of digestion techniques, in which particulates are entrapped on a filter surface. However, the actual filtering efficiency of various pore sizes as applicable to collecting fibrous material has not been tested. The present study evaluates such filtration efficiency by using a series of back-to-back filters of various sizes. It was confirmed that fibers pass through the pores and that with the larger pore sizes an appreciable loss of small fibers can occur. It is suggested that a filter with 0.2-micron pore size offered a reasonable compromise for both filtration efficiency as well as sufficiently rapid filtration rates for most studies.


Assuntos
Amianto/análise , Filtros Microporos , Amianto Amosita , Tamanho da Partícula
18.
Acta Neuropathol ; 78(3): 310-6, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2763803

RESUMO

The relationship of free arachidonic acid (AA) to cellular permeability, lipid peroxidation and physical state "fluidity" of the membrane was investigated in cultured endothelial cells (EC) dissociated from cerebral microvessels of rats. The results demonstrate that AA can induce a reversible alteration of endothelial permeability to trypan blue albumin (TBA). Exposure of EC to AA increases membrane "fluidity" as measured by fluorescence anisotropy using 1,6-diphenyl-1,3,5 hexatriene as a fluorescent probe. The AA modification of EC membrane "fluidity" is not associated with changes in EC permeability. Addition of AA and H2O2 to the incubation medium of EC leads to persistant alteration of EC permeability which can be prevented by catalase treatment. Both AA and H2O2 induce a greater formation of malondialdehyde, the product of lipid peroxidation, than AA alone. These findings strongly suggest that a release of AA either from the capillary or cellular membrane of the brain under a pathological condition may alone or through a peroxidative process alter the function of blood-brain barrier.


Assuntos
Ácidos Araquidônicos/farmacologia , Encéfalo/irrigação sanguínea , Endotélio Vascular/efeitos dos fármacos , Animais , Permeabilidade Capilar , Células Cultivadas , Endotélio Vascular/ultraestrutura , Polarização de Fluorescência , Peroxidação de Lipídeos/efeitos dos fármacos , Fluidez de Membrana/efeitos dos fármacos , Microcirculação , Microscopia Eletrônica de Varredura , Ratos
19.
Cytobios ; 56(224): 7-15, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3251681

RESUMO

Asbestos is a recognized carcinogen which is widely available for environmental exposure. Since all members of our society are exposed to asbestos containing environments and, indeed, have asbestos fibres in their lungs, the concern exists as to its significance in contributing to the incidence of lung cancer in such populations. The asbestos burden was compared in lung tissue from control and lung cancer patients who had resided in a non-urban environment. There were no significant differences between the asbestos burdens in both age matched groups; however, the proportions of amphiboles to chrysotile were different from those reported in previous urban based studies. This difference was suggested to be attributable to chrysotile exposure in urban air. All patients had appreciable non-asbestos fibres within their lungs. The results indicate that when comparing any dust burden in lungs, it is necessary to have data from regional control populations before attempting to explore causal-disease relationships.


Assuntos
Amianto/análise , Neoplasias Pulmonares/análise , Pulmão/análise , Adulto , Idoso , Poluentes Atmosféricos/efeitos adversos , Amianto/efeitos adversos , Humanos , Neoplasias Pulmonares/epidemiologia , Pessoa de Meia-Idade , Texas , Saúde da População Urbana
20.
Am J Ind Med ; 27(2): 207-15, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7755011

RESUMO

Tissue from an individual with a history of exposure to asbestos and other dust was referred for particulate analysis. The digested material was reviewed by light microscopy to establish the numbers of ferruginous bodies per gram of tissue. Typical asbestos bodies were found at levels consistent with occupational exposure. A second type of elongated ferruginous body was formed on a thicker transparent core which suggested the minerals were sheet silicates. The number of ferruginous bodies with nonasbestos cores was over four times the number of asbestos cored ferruginous bodies. Electron microscopy was used to confirm the core composition of both populations and also to establish the levels of uncoated fibers. The nonasbestos ferruginous bodies were predominantly formed on talc.


Assuntos
Adenocarcinoma/etiologia , Amianto/análise , Neoplasias Pulmonares/etiologia , Doenças Profissionais/etiologia , Talco/análise , Humanos , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade
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