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1.
Biotechnol Lett ; 43(7): 1487-1502, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33822305

RESUMO

The interest in bioactive compounds from microalgae is increasing since they have medicinal and nutritional areas. The present work aims to evaluate the potential pharmaceutical interest of extracts from three eustigmatophyte strains from the Coimbra Collection of Algae (ACOI): Chlorobotrys gloeothece, Chlorobotrys regularis and Characiopsis aquilonaris. Antioxidant and antiproliferative activities were determined as well as chlorophyll a, carotenoid and phenolic total contents. In addition, major pigments and sterols were identified and quantified. The three strains were grown until the stationary phase and then the biomass was extracted. Antioxidant activity was measured by TEAC, DPPH and FRAP assays and antiproliferative effect was assessed by the MTT method on MCF-7, PC-3 and NHDF cells. The pigment and phenolic total contents were determined by spectrophotometry. Of these strains, C. aquilonaris showed the highest antioxidant activity measured by TEAC and FRAP assays (23.98 ± 0.01 µmol TE eq g-1 DW and 42.57 ± 0.04 µmol TE eq g-1 DW, respectively), a selective effect in reduting MCF-7 cells proliferation and a larger amount of chlorophyll a, carotenoids and phenolic content (18.40 ± 0.00 µg chlorophyll a mg-1 DW, 2.27 ± 0.00 mg carotenoids g-1 DW and 6.23 ± 0.01 mg GAE g-1 DW, respectively). A positive correlation between chlorophyll a and TEAC assay was observed, as well as between carotenoids and TEAC and FRAP assays, suggesting these compounds as important contributors to significant antioxidant activity. Violaxanthin, cholesterol and stigmasterol were present in larger amount in C. aquilonaris while C. regularis showed a higher amount of ß-carotene. These results suggest that these three ACOI eustigmatophytes are promising for applications in the improvement of human health, particularly in cancer prevention and treatment.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Fatores Biológicos/farmacologia , Estramenópilas/crescimento & desenvolvimento , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Fatores Biológicos/química , Fatores Biológicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Clorofila A/química , Colesterol/química , Humanos , Células MCF-7 , Células PC-3 , Estigmasterol/química , Estramenópilas/química , Xantofilas/química , beta Caroteno/química
2.
Dermatol Online J ; 26(3)2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32609451

RESUMO

Eosinophilic dermatosis of hematologic malignancy (EDHM) is a dermatosis characterized by tissue eosinophilia that has been previously reported as insect bite-like reaction. It is a rare condition with a wide variety of clinical presentations ranging from papules, nodules, or blisters that simulate arthropod bites, to the formation of plaques of differing sizes. We report a case of eosinophilic dermatosis of hematologic malignancy in a patient with a hematoproliferative disorder.


Assuntos
Eosinofilia/patologia , Síndromes Mielodisplásicas/complicações , Síndromes Paraneoplásicas/patologia , Dermatopatias/patologia , Idoso , Eosinofilia/etiologia , Humanos , Masculino , Dermatopatias/etiologia
3.
Sci Rep ; 13(1): 7251, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142611

RESUMO

Beaches combined with sloping structures are frequently the first element of defense to protect urban areas from the impact of extreme coastal flooding events. However, these structures are rarely designed for null wave overtopping discharges, accepting that waves can pass above the crest and threat exposed elements in hinterland areas, such as pedestrians, urban elements and buildings, and vehicles. To reduce risks, Early Warning Systems (EWSs) can be used to anticipate and minimize the impacts of flooding episodes on those elements. A key aspect of these systems is the definition of non-admissible discharge levels that trigger significant impacts. However, large discrepancies in defining these discharge levels and the associated impacts are found among the existing methods to assess floodings. Due to the lack of standardization, a new conceptual and quantitative four-level (from no-impact to high-impact) categorization of flood warnings (EW-Coast) is proposed. EW-Coast integrates and unifies previous methods and builds on them by incorporating field-based information. Thus, the new categorization successfully predicted the impact level on 70%, 82%, and 85% of the overtopping episodes affecting pedestrians, urban elements and buildings, and vehicles, respectively. This demonstrates its suitability to support EWSs in areas vulnerable to wave-induced flooding.

4.
Transfus Med ; 22(2): 116-21, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22283663

RESUMO

OBJECTIVE: Evaluation of the antimicrobial effect of skin disinfection techniques is essential to avoid the transmission of infectious agents during blood transfusion. The aim of this study was to examine the effectiveness of two methods of arm skin disinfection used in blood donors at a Hemotherapy Center in Brazil that represents an important centre for distributing haemocomponents to many cities in the country. METHODS: Two skin disinfection techniques in 50 blood donors were evaluated. For the first arm, 10% povidone-iodine/two-stage technique was used. On the opposite arm, 0.5% chlorhexidine digluconate alcohol solution/one-stage technique was used. The swabs were seeded on three culture media: blood agar, mannitol salt agar and Mac Conkey agar. Automated bacterial classification based on biochemical tests/specific substrates was performed. Donor characteristics were collected using the computerised system of the Hemotherapy Center. RESULTS: We found that microbial reduction was significantly higher for 10% povidone-iodine technique (98.57-98.87%) when compared with 0.5% chlorhexidine technique (94.38-95.06%). The species Leuconostoc mesenteroides and Staphylococcus hominis showed resistance to both disinfection techniques. We did not find statistically significant relationships between donor characteristics and microbial reduction. CONCLUSIONS: Arm skin disinfection with 10% povidone-iodine produced better antimicrobial activity. We must acknowledge that 10% povidone-iodine technique has the limitation of being a two-stage method. However, prevention of adverse events due to bacterial contamination and transfusion reactions should be prioritised. Production of hypoallergenic and stronger antiseptics that allowed a safe one-stage disinfection technique should be encouraged in health systems, not only in Brazil but also around the world.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Braço , Doadores de Sangue , Desinfecção/métodos , Controle de Infecções/métodos , Pele , Brasil , Feminino , Humanos , Masculino
5.
Dermatol Online J ; 17(3): 5, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21426871

RESUMO

Porokeratosis is a group of hereditary or acquired diseases with abnormal epidermal keratinization. A 71-year-old man was admitted to the Surgery Department after an attack of acute pancreatitis complicated with pancreatic necrosis, which required surgical resection. Three weeks after the admission, the patient was observed by our Dermatology department with sudden onset of a generalized eruption of asymptomatic flat papules with a hyperkeratotic rim, sparing the face, palms, soles, and mucous membranes. A skin biopsy was performed at the border of a leg lesion, which disclosed the presence of cornoid lamella, confirming the clinical diagnosis of disseminated superficial porokeratosis (DSP). The skin eruption spontaneously subsided about one month after pancreatic resection. The late onset of DSP in our patient may represent a type of immunosuppression-induced porokeratosis. Possibly, the pathologic clone of keratinocytes for porokeratosis was present, but remained latent until there was a decrease in the immunological status. It is possible that this relative and transient state of immunosuppression was the result of the concurrent necrotizing pancreatitis. This case represents an unusually good outcome of DSP. To the authors best knowledge, this is the first case of DSP related to severe acute pancreatitis.


Assuntos
Pancreatectomia , Pancreatite/cirurgia , Poroceratose/etiologia , Poroceratose/patologia , Complicações Pós-Operatórias/patologia , Doença Aguda , Idoso , Humanos , Masculino , Necrose , Pâncreas/patologia , Pancreatite/patologia , Poroceratose/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Remissão Espontânea
6.
Sci Total Environ ; 768: 144987, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33736349

RESUMO

Human occupation of and alteration of the world's coast has transformed large stretches of it into Coupled Human-Natural Systems (CHANS) in which humans both influence and are influenced by coastal evolution. In such systems, human activity is as critical on natural resilience as processes and sediment supply derived from the natural setting. Pre- and post-storm observations of these interactions on the intensively developed Atlantic coast of the Gulf of Cádiz, (Spain and Portugal) are examined to determine natural and engineering resilience. Three case studies are used in three CHANS, showing that human interventions interact in complex ways with the natural system influencing post-storm recovery. In natural coasts, storm impact is assessed in terms of geomorphological response; on developed coasts, it is quantified as damage to infrastructure or loss of amenity. Preparedness, availability of resources, choice of response and the speed at which human agencies respond affect resilience for post-storm beach behaviour. Results show in some sites natural resilience adjusting by post-storm sediment transfers and an equilibrium morphology that may differ from pre-storm morphology; engineering resilience ensured that CHANS regained their pre-storm human infrastructure and amenity. Their management requires a fundamentally different approach to that of natural coastlines. The current immature stage of understanding of CHANS (especially the human preparedness and response components) is illustrated by the case studies presented where short-term political decisions and reactions to storms play a strong role in post-storm response. The nature and extent of many developed coasts as CHANS is slowly becoming more widely acknowledged, but to increase natural resilience and decrease vulnerability in CHANS better planning is required so that future storms are anticipated and when they happen, pre-planned human response actions are activated. Storms are an integral and inevitable element in the behaviour of coastal CHANS, not a disaster or emergency.

7.
J Exp Med ; 171(1): 351-6, 1990 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-2404083

RESUMO

U937 cells attach to the RGDS-containing 80-kD fragment of fibronectin (Fn). The present report examined whether these cells recognize other domains of Fn. U937 cells attach to a 38-kD fragment derived from the A chain of Fn, which includes the Hep II domain and most of the alternatively spliced IIICS region. U937 did not bind to a 58-kD fragment derived from the B chain (which lacks IIICS) and has the Hep II site. They also did not bind to a 31-kD COOH-terminal fibrin-binding fragment or to a 29-kD fragment containing the Hep I domain. Cell adhesion to the 38-kD fragment was not inhibited by the 80-kD fragment, by GRGDSPC synthetic peptides, or by a mAb directed to the RGDS-containing domain of Fn. Attachment was completely inhibited by the 38-kD fragment and by the synthetic peptide CS-1, comprising the first 25 amino acid residues of IIICS. These results indicate that U937 cells interact with two sites of Fn, the RGDS-containing region, and the IIICS region.


Assuntos
Adesão Celular , Fibronectinas/genética , Sequência de Aminoácidos , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Fibronectinas/fisiologia , Humanos , Linfoma Difuso de Grandes Células B , Dados de Sequência Molecular , Peso Molecular , Monócitos , Oligopeptídeos/síntese química , Oligopeptídeos/farmacologia , Splicing de RNA
8.
Sci Total Environ ; 650(Pt 2): 2499-2511, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30293004

RESUMO

Environmental concerns have been changing the way of looking for solutions to problems. The hydrosphere, together with its biosphere, has been feeling the impact of many pollutants, used for instance in the marine industry for economic reasons or lack of knowledge of their effects. In particular biocides, applied as coatings in paints, are released into the waters becoming toxic and persistent extending their action to an area far beyond the initial coated surface they should protect. In order to minimize these side effects, two biocides, Irgarol (I) and Econea (E), were covalently attached to polyurethane (PU) and foul-release silicone based (PDMS) marine paints through an isocyanate linker. Their antifouling bioactivity was better in PDMS coatings, both for single (Econea) and combined biocides (E/I ratio = 1.5) with contents lower than 0.6 wt%. The treated samples remained almost clean after more than one year immersion in the Portuguese shore of the Atlantic Ocean, and after about 24 weeks under the tropical conditions of Singapore (Fouling rate < 1%). Complementary biofilm adhesion susceptibility tests against Pseudoalteromonas tunicata D2 showed adhesion reduction higher than 90% for PU formulations containing single biocides and close to 100% for PDMS with combined biocides. The eco-toxicity assessment evidenced a low environmental impact, in accordance with the European standards. In addition, shipping field trial tests showed the best antifouling performance for the Econea-based PDMS formulations (E = 0.6 wt%), which remained clean for about nine months in open seawaters, proving the efficacy of this non-release strategy, when applied under dynamic conditions.


Assuntos
Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Diatomáceas/efeitos dos fármacos , Desinfetantes/farmacologia , Pirróis/farmacologia , Triazinas/farmacologia , Pintura/análise , Navios
11.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 977-984, May-June, 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1129703

RESUMO

O objetivo deste estudo foi avaliar o efeito da suplementação durante diferentes períodos gestacionais sobre a produção de lã de ovelhas e cordeiros da raça Ideal. Foram utilizadas 53 ovelhas da raça Ideal, com escore corporal médio (3), inseminadas pela técnica de laparoscopia, com sêmen fresco de um único reprodutor; e seus cordeiros. Os tratamentos experimentais foram: sem suplementação (n=9); suplementação do início da gestação até 50 dias (n=11); suplementação dos 51 aos 100 dias de gestação (n=11); suplementação dos 101 aos 150 dias - final da gestação (n=11); e suplementação durante toda a gestação (n=11). A suplementação foi a 1,5% do peso corporal. Amostras de lã das ovelhas e dos cordeiros foram tomadas na região do costilhar esquerdo e enviadas ao laboratório para análises objetivas de finura de lã. As suplementações no terço final e durante toda a gestação proporcionavam os melhores resultados, com aumento de produção de lã e de peso das ovelhas. Ovelhas que receberam suplementação durante toda a gestação apresentaram maior diâmetro de fibra e peso corporal. O desempenho de lã dos cordeiros não foi influenciado pela alimentação de ovelhas durante a gestação.(AU)


The objective of this study was to evaluate the effect of supplementation during different gestational periods on the wool production of sheep and lambs of the Ideal breed. Fifty-three adult Ideal sheep were used, with a mean body score inseminated by the laparoscopy technique using fresh sperm from a single breeder and his lambs. Treatment groups: No supplementation (n=9); Supplementation in the beginning of gestation up to 50 days (n=11); Supplementation from 51 to 100 days of gestation (n=11); Supplementation from 101 to 150 days - end of gestation (n=11) ;and Supplementation throughout the gestation (n=11). The supplementation was at 1.5% of body weight. After birth, lambs were kept with their mothers in cultivated pasture of black oats and ryegrass. Wool samples from sheep and lambs were taken in the left-hand region and sent to the laboratory for objective analyzes of wool fineness. The supplementation performed in the final third and throughout the gestation provides the best results, with increased sheep weight. Ewes that received supplementation throughout pregnancy had greater fiber diameter and body weight. The wool performance of lambs was not influenced by feeding sheep during gestation.(AU)


Assuntos
Animais , , Peso Corporal , Ovinos , Suplementos Nutricionais , Fibra de Lã/análise
12.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1874-1880, Sept.-Oct. 2020. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131528

RESUMO

The objective of this study was to evaluate, for two years, the performance of 124 female and 105 male Braford calves born during the first and second halves of the same calving season and the effects of birth period on the development of males until slaughter, as yearlings, and of females until calving, after having mated at 13-15 months of age. Early-born females were heavier than those born late at weaning (119.3 vs 109.9kg; P<0.05), at the start of the breeding season (275.0 vs 263.0kg; P<0.05), and at the end of the breeding season (300.0 vs 289.5kg; P<0.05), in addition to being more fertile (70 vs 50% pregnancy rate). There was no difference (P>0.05) in the development of males born early in relation to those born late, except for weaning weight, which was higher in the former. Steers born early were ready for slaughter at a younger age (459.6 vs 490.1 days; P<0.05), and both groups (early- and late-born) had a body condition classified as fat (4.21 points). In intensive production systems, both male and female calves perform better if they are born during the first half of the calving season.(AU)


O objetivo deste estudo foi avaliar, por dois anos, o desempenho de 124 bezerras e 105 bezerros Braford nascidos durante a primeira e segunda metades da mesma estação, bem como os efeitos do período de nascimento no desenvolvimento dos machos até o abate e das fêmeas até o primeiro parto, após serem acasalados entre 13/15 meses de idade. As fêmeas nascidas precocemente foram mais pesadas do que as nascidas tardiamente ao desmame quando bezerras (119,3 vs. 109,9kg; P<0,05), no início da estação reprodutiva (275,0 vs. 263,0kg; P<0,05) e no final da estação reprodutiva (300,0 vs. 289,5kg; P<0,05), além de terem maior fertilidade (taxa de prenhez 70 vs. 50%). Não houve diferença (P>0,05) no desenvolvimento de bezerros nascidos precocemente em relação aos nascidos mais tardiamente, exceto no peso ao desmame, com superioridade dos primeiros. Os novilhos nascidos mais cedo ficaram prontos para o abate à idade mais jovem (459,6 vs. 490,1 dias; P<0,05), e ambos os grupos (nascidos precoce e tardiamente) tinham uma condição corporal classificada como gordura (4,21 pontos). Em sistemas de produção intensiva, os bezerros machos e fêmeas nascidos precocemente, na primeira metade da estação de parição, possuem melhor desempenho.(AU)


Assuntos
Animais , Bovinos , Reprodução , Aumento de Peso , Crescimento e Desenvolvimento/fisiologia
13.
AIDS ; 10(10): 1135-40, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8874631

RESUMO

OBJECTIVE: To determine the relative prevalence of HIV-1 and HIV-2 and to evaluate the World Health Organization testing strategy for HIV diagnosis in a low-risk population in Brazil. In addition, to assess risk factors for HIV infection. DESIGN: Sera obtained from 9885 consecutive blood donors were screened in parallel by two HIV enzyme-linked immunosorbent assays (ELISA) with different antigen composition and test principles (Ortho HIV-1 and Wellcozyme HIV-1/2). Samples reactive to either ELISA were submitted to a Western blot assay and to a rapid HIV-1/2 ELISA (Sero-Immuno Diagnostics). An ELISA test with specific HIV-1/HIV-2-derived synthetic peptide was used to discriminate between samples reactive on the Wellcozyme HIV-1/2 assay. Demographic and serological data were used to address risk factors for HIV infection. RESULTS: All the 28 Western blot-confirmed positive samples were reactive in both Ortho HIV-1 and Wellcozyme HIV-1/2 assays (sensitivity, 100%). The Wellcozyme HIV-1/2 specificity (99.9%) was higher than Ortho HIV-1 (99.5%). If sample reactivity to both tests was considered positive, the sensitivity and specificity of the screening would be 100%. However, further analysis with a third rapid HIV-1/2 ELISA reduced both the sensitivity and the specificity of the sequential testing strategy. Discrimination between HIV-1 and HIV-2 showed evidence for the presence of HIV-1 only. Finally, in the group aged 18-35 years, the presence of serological markers of hepatitis C virus and hepatitis B virus infections and the elevated levels of beta 2-microglobulin were variables associated with the identification of HIV-1-seropositive blood donors. CONCLUSION: In a low-risk population, application of two high quality ELISA tests with different antigens and test principles can replace the use of the Western blot. In addition to the cost being reduced by 10-16%, a rapid diagnosis and the absence of indeterminate Western blot results confer an advantage to this strategy.


Assuntos
Doadores de Sangue , Infecções por HIV/prevenção & controle , HIV-1 , HIV-2 , Programas de Rastreamento/métodos , Organização Mundial da Saúde , Adulto , Algoritmos , Western Blotting , Brasil/epidemiologia , Ensaio de Imunoadsorção Enzimática , Estudos de Avaliação como Assunto , Guias como Assunto , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Humanos , Prevalência , Fatores de Risco , Sensibilidade e Especificidade
14.
AIDS ; 7(9): 1191-7, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8216975

RESUMO

OBJECTIVE: To examine the genetic heterogeneity of the V3 region of HIV-1 gp120 from 22 Brazilian HIV-1 specimens. DESIGN: Genetic heterogeneity was examined by DNA sequencing of the C2 V3 region of the HIV-1 envelope (env) gene from polymerase chain reaction (PCR)-amplified HIV-1 DNA. Deduced amino-acid sequences were compared to determine the extent of amino-acid conservation among the Brazilian specimens. Genetic similarity among and between the Brazilian specimens and other previously published HIV-1 isolates was analyzed by principal co-ordinate and DNA parsimony methods. METHODS: A 282 base pair (bp) region of a 1.5 kilo (k) bp PCR-amplified HIV-1 env fragment was sequenced by a Taq dye-labeled primer cycle sequencing reaction. Nucleotide sequences were used to analyze inter-specimen relationships based on overall nucleotide sequence similarity and DNA parsimony principles. RESULTS: Amino-acid comparison showed that 15 of the 35 (43%) residues of the V3 loop were conserved among the Brazilian specimens. Nine of the 22 (40%) Brazilian specimens contained the North American-European GPGR tetrapeptide motif, while eight (36%) contained the GWGR motif, previously reported in Japanese isolates. Principal co-ordinate analysis demonstrated that 19 of the 20 examined Brazilian HIV-1 specimens were more similar to North American and Haitian isolates than to African isolates. Similar results were also obtained by DNA parsimony analysis. CONCLUSION: The majority of the Brazilian specimens examined are more genetically related to North American and Haitian HIV-1 isolates than to African isolates. This finding and the presence of a GWGR V3 loop motif in some Brazilian isolates may be important for vaccine development.


Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Proteína gp120 do Envelope de HIV/genética , HIV-1/genética , Fragmentos de Peptídeos/genética , Sequência de Aminoácidos , Brasil , DNA Viral , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Homologia de Sequência de Aminoácidos
15.
Blood Rev ; 11(2): 91-104, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9242992

RESUMO

The human T-cell lymphotropic viruses type I and type II are closely related human retroviruses that have similar biological properties, genetic organization and tropism for T lymphocytes. Along with the simian T-cell lymphoma virus type I, they define the group of retroviruses known as the primate T-cell leukemia/lymphoma viruses. Initially identified in 1980, the human T-cell lymphotropic virus type I has been implicated as the etiologic agent of adult T-cell leukemia/lymphoma and of a degenerative neurologic disorder known as tropical spastic paraparesis or human T-cell lymphotropic virus type I-associated myelopathy. The intriguing link between human T-cell lymphotropic virus type, T-cell malignancy, and a totally unrelated and non-overlapping neurological disorder suggests divergent and unique pathogenetic mechanisms. This review will address the epidemiology, molecular biology, and pathogenesis of human T-cell leukemia viruses.


Assuntos
Infecções por HTLV-I/epidemiologia , Infecções por HTLV-II/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Vírus Linfotrópico T Tipo 2 Humano/patogenicidade , Adulto , Animais , Produtos do Gene rex/metabolismo , Produtos do Gene tax/metabolismo , Infecções por HTLV-I/genética , Infecções por HTLV-I/transmissão , Infecções por HTLV-II/genética , Infecções por HTLV-II/transmissão , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Humanos
16.
J Acquir Immune Defic Syndr (1988) ; 7(12): 1224-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7965632

RESUMO

We compared the performance of a rapid and simple anti-CD4 antibody-coated microsphere assay with flow cytometry and immunofluorescence for quantitation of absolute count of CD4+ T lymphocytes. A longitudinal evaluation of CD4+ T lymphocytes by flow cytometry and microsphere assay in 10 human immunodeficiency virus (HIV)-seronegative and 59 HIV-seropositive individuals was conducted over a period of 9 months. Standard flow cytometry analysis was performed to establish the absolute CD4+ T-lymphocyte count. The microsphere assay uses whole blood; CD14+ and CD4+ cells are first blocked by small latex beads coated with anti-CD14 antibody, and remaining cells are stained with larger anti-CD4 antibody-coated beads. Cells rosetted with only anti-CD4 antibody-coated beads are counted with use of a hemacytometer. Immunofluorescence microscopy was performed by standard techniques with use of peripheral blood mononuclear cells. The predictive value for stratification of HIV-seropositive patients by CD4+ T-lymphocyte values of < 200/microliters was 95% when the microsphere method was compared with flow cytometry. A correlation coefficient of 0.91 between the two assay methods was demonstrated in 281 CD4+ T-lymphocyte tests for absolute count. Finally, the flow cytometry method yielded better results than did the microsphere assay and immunofluorescence microscopy, in descending order of accuracy. The microsphere method should be effective in determining absolute CD4+ T-lymphocyte count in developing countries where, for a variety of reasons, no other method can be reliably performed.


Assuntos
Contagem de Linfócito CD4/métodos , Soropositividade para HIV/imunologia , Estudos de Coortes , Estudos de Avaliação como Assunto , Citometria de Fluxo , Imunofluorescência , Soronegatividade para HIV/imunologia , Soropositividade para HIV/sangue , Humanos , Microesferas , Estudos Prospectivos , Formação de Roseta , Sensibilidade e Especificidade
17.
Trans R Soc Trop Med Hyg ; 90(2): 122-5, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8761567

RESUMO

Sera from 653 female prostitutes and 153 male sexual clients living in the city of Santos, São Paulo, Brazil, were tested for the presence of antibodies to human T cell lymphotropic virus types I and II. Seroprevalence for HTLV-I in the females was 2.8% and in the males 2.0%. Infection by HTLV-II could not be demonstrated. Seropositivity to HTLV-I was not associated with intravenous drug use, modality of sexual behaviour or a history of sexually transmitted disease. Among the prostitutes, the prevalence of anti-HTLV-I antibodies was 3 times higher in those with a history of blood transfusion (P = 0.01).


Assuntos
Infecções por HTLV-I/epidemiologia , Infecções por HTLV-II/epidemiologia , Trabalho Sexual/estatística & dados numéricos , Adolescente , Adulto , Transfusão de Sangue , Brasil/epidemiologia , Feminino , Anticorpos Anti-HTLV-I/análise , Infecções por HTLV-I/imunologia , Anticorpos Anti-HTLV-II/análise , Infecções por HTLV-II/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Infecções Sexualmente Transmissíveis/complicações , Abuso de Substâncias por Via Intravenosa
18.
J Infect ; 31(2): 163-4, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8666851

RESUMO

We give details of a patient infected with HIV-2 which had what we believe to be the longest asymptomatic period so far reported. The infection was probably acquired though a blood transfusion in Africa 27 years ago. At present the patient remains asymptomatic and her cellular defence mechanisms, evaluated by CD+4 lymphocyte counts and hypersensitivity skin tests, are not severely compromised. HIV-2 has come distinct epidemiological, clinical and biological features which are different from the related HIV-1 and deserve investigation in order for its natural history to be better understood.


Assuntos
Infecções por HIV/diagnóstico , HIV-2/isolamento & purificação , Reação Transfusional , Feminino , Guiné-Bissau , Infecções por HIV/transmissão , Soroprevalência de HIV , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
19.
Braz J Med Biol Res ; 19(6): 699-706, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3307958

RESUMO

1. The ability of peripheral blood mononuclear cells (PBMC) from Chagas' disease patients to induce monocyte procoagulant activity (PCA) in response to concanavalin A (Con A) and to a Con A induced lymphokine was studied. 2. In spite of the variability of PCA levels among both chagasic patients and normal controls, statistical analysis of the data permitted us to draw the following general conclusions. 3. The Con A-induced monocyte PCA measured in 17 assays of 15 chagasic patients was significantly lower than the PCA response of 18 normal controls or of 11 patients with non-chagasic myocardiopathies. 4. The response of PBMC from chagasic patients to lymphokine was also lower than that observed for normal controls. 5. These results suggest that monocytes from chagasic patients are deficient for the generation of PCA which is an in vitro correlate of the delayed-type hypersensitivity reaction.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Cardiomiopatia Chagásica/sangue , Concanavalina A/farmacologia , Linfocinas/farmacologia , Monócitos/fisiologia , Adulto , Animais , Fatores de Coagulação Sanguínea/metabolismo , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Trypanosoma cruzi/metabolismo
20.
Braz J Med Biol Res ; 28(1): 51-7, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7581028

RESUMO

Some Brazilian regions are considered to be endemic for human T-cell leukemia/lymphoma virus type I (HTLV-I) infection. Several studies have shown a high prevalence of HTLV-I infection among different groups such as blood donors, hemophiliacs and patients suffering from hematological and neurological diseases. Cases of adult T-cell leukemia/lymphoma as well as tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM) have already been described in Brazil. We report the isolation of an HTLV-I strain from cultured lymphocytes of a TSP/HAM patient. An IL-2-dependent HTLV-I-infected T-cell line (ROB) expressing viral antigens was established and reverse transcriptase activity could be detected in the culture supernatant. Ultrastructural analysis showed immature and mature HTLV retrovirus particles. Finally, HTLV-I provirus type I was demonstrated by the polymerase chain reaction. This is the first isolation completely carried out in Latin America. The molecular analysis of viral strains, now in progress, should clarify the molecular epidemiology of HTLV-I in Brazil.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Linfócitos/virologia , Paraparesia Espástica Tropical/epidemiologia , Adulto , Sequência de Bases , Brasil/epidemiologia , Genoma Viral , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/ultraestrutura , Humanos , Masculino , Dados de Sequência Molecular , Paraparesia Espástica Tropical/virologia
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