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BACKGROUND: Violence against women remains an important issue of inequality in African societies, with several consequences to health, social and economic status. This study aims to identify the factors related to the perception of intimate partner violence in Benin. METHODS: Data on intimate partner violence was collected by conducting live interviews, and from the Benin Demographic and Health Survey 2012. The dependent variable was acceptance of intimate partner violence. The independent variables were socio-demographic features such as age, level of education, matrimonial status, ethnicity, religion, place of residence and the index of economic well-being. Logistic regressions were performed and odds ratios (OR) with a confidence interval of 95% (CI95%) were estimated. RESULTS: Among the 21,574 people who answered the questions relating to violence against women by an intimate partner, the prevalence of acceptance of intimate partner violence was 15.77%. Ethnicity, level of education, administrative department of residence, religion, and socio-economic quintile were factors associated with the respondents' acceptance of violence against women by an intimate partner. CONCLUSION: Acceptance of intimate partner violence could be a major obstacle to the success of some health programs. There is a need to break the norms that support the vulnerability of women in Beninese society.
Assuntos
Inquéritos Epidemiológicos , Violência por Parceiro Íntimo/psicologia , Violência por Parceiro Íntimo/estatística & dados numéricos , Adolescente , Adulto , Benin , Feminino , Humanos , Relações Interpessoais , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Fatores Socioeconômicos , Adulto JovemRESUMO
We report an anomalous wide broadening of the emission spectra of an electronic excitation confined in a two-dimensional potential. We attribute these results to an extremely fast radiative decay rate associated with superradiant emission from the ensemble of confined electrons. Lifetimes extracted from the spectra are below 100 fs and, thus, 6 orders of magnitude faster than for single particle transitions at similar wavelength. Moreover, the spontaneous emission rate increases with the electronic density, as expected for superradiant emission. The data, all taken at 300 K, are in excellent agreement with our theoretical model, which takes into account dipole-dipole Coulomb interaction between electronic excitations. Our experimental results demonstrate that the interaction with infrared light, which is usually considered a weak perturbation, can be a very efficient relaxation mechanism for collective electronic excitations in solids.
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The vote shares by party on a given subdivision of a territory form a vector called composition (mathematically, a vector belonging to a simplex). It is interesting to model these shares and study the impact of the characteristics of the territorial units on the outcome of the elections. In the political economy literature, few regression models are adapted to the case of more than two political parties. In the statistical literature, there are regression models adapted to share vectors including Compositional Data (CoDa) models, but also Dirichlet models, and others. Our goal is to discuss and illustrate the use CoDa regression models for political economy models for more than two parties. The models are fitted on French electoral data of the 2015 departmental elections.
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For the epidemiological monitoring and clinical case management of leishmaniasis, determination of the causative Leishmania species gains importance. Current assays for the Old World often suffer from drawbacks in terms of validation on a geographically representative sample set and the ability to recognize all species complexes. We want to contribute to standardized species typing for Old World leishmaniasis. We determined the ribosomal DNA internal transcribed spacer 1 sequence of 24 strains or isolates, and validated four species-specific polymerase chain reactions (PCRs) amplifying this target. They discriminate L. aethiopica, L. tropica, L. major, and the L. donovani complex, use the same cycling conditions, and include an internal amplification control. Our PCRs amplify 0.1 pg of Leishmania DNA, while being 100% specific for species identification on an extensive panel of geographically representative strains and isolates. Similar results were obtained in an endemic reference laboratory in Kenya. Species could also be identified in clinical specimens. The presented PCRs require only agarose gel detection, and have several other advantages over many existing assays. We outline potential problems, suggest concrete solutions for transferring the technique to other settings, and deliver the proof-of-principle for analyzing clinical samples.
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Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose/diagnóstico , Parasitologia/métodos , Reação em Cadeia da Polimerase/métodos , Animais , Primers do DNA/genética , DNA de Protozoário/genética , DNA Espaçador Ribossômico/genética , Cães , Eletroforese em Gel de Ágar , Humanos , Leishmania/genética , Leishmaniose/parasitologia , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: This study aimed to compare four anti-SARS-CoV-2 immunoassays in populations presenting different clinical severity levels. METHODS: Three populations were included: "severe-to-critical" ICU-hospitalized patients (n = 18), "mild-to-moderate" hospitalized patients (n = 16) and non-hospitalized symptomatic patients (n = 24). Four commercial immunoassays were analyzed and validated: anti-IgG ARCHITECT® (Abbott), anti-Total antibodies (Ab) VITROS® (Ortho Clinical Diagnostics), anti-IgG NovaLisa® (NovaTec Immundiagnostica) and Healgen® IgM and IgG (Zhejiang Orient Gene Biotech). Sensitivities were evaluated according to days post-symptoms onset (pso). Specificities were evaluated on SARS-CoV-2-negative control sera collected before January 2020. RESULTS: A majority of severe-to-critically ill patients showed detectable Ab already at day 14 and sensitivities reached 100 % after 22 days pso. For patients with "mild-to-moderate" illness, sensitivities increased by at least 5-fold from day 0 to day 14 pso. Non-hospitalized symptomatic individuals already seroconverted at day 14 days pso with 100 % sensitivities for Total Ab VITROS®. Specificities were evaluated at 97 % for ARCHITECT® and NovaLisa®, 98 % for VITROS® and at 94 % for Healgen® combined IgM and IgG. Five "severe-to-critically" ill patients presented high positive Ab levels for at least 16 weeks pso. CONCLUSION: The Ab levels and the evaluated sensitivities, representing the true positive rate, increased overtime and were related to the COVID-19 severity. Automated Total Ab immunoassay showed better sensitivities and specificity for immunological surveillance and vaccine evaluation.
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Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Imunoensaio/métodos , Humanos , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Sensibilidade e EspecificidadeRESUMO
Though brushes are no longer used on the hands and forearms during the surgical scrub, they are still widely used on the nails. The aim of this study was to determine whether nail picks and nail brushes are effective in providing additional decontamination during a surgical hand scrub. A total of 164 operating department staff were randomised to undertake one of the following three surgical hand-scrub protocols: chlorhexidine only; chlorhexidine and a nail pick; or chlorhexidine and a nail brush. Bacterial hand sampling was conducted before and 1h after scrubbing using a modified version of the glove juice method. No statistically significant differences in bacterial numbers were found between any two of the three intervention groups. Nail brushes and nail picks used during surgical hand scrubs do not decrease bacterial numbers and are unnecessary.
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Desinfecção das Mãos/métodos , Controle de Infecções/instrumentação , Unhas , Procedimentos Cirúrgicos Operatórios , Administração Cutânea , Anti-Infecciosos Locais/administração & dosagem , Clorexidina/administração & dosagem , Contagem de Colônia Microbiana , Feminino , Humanos , MasculinoRESUMO
The applications of highly specific and sensitive molecular techniques based on polymerase chain reaction (PCR) have constituted a valuable tool for the diagnosis of schistosomiasis and also for the detection of schistosome infections in the snail intermediate hosts. The common method of detecting PCR amplicons is gel electrophoresis in the presence of ethidium bromide, a carcinogen, which is followed by UV transillumination. Other methods, which are available for detecting PCR products, are real-time PCR, PCR-enzyme-linked immunosorbent assay (PCR-ELIZA) and mass spectrometry but they are cumbersome while they are sometimes complex and expensive. Therefore, a simple method of PCR product detection would be a welcome idea and a most valuable tool particularly in disease endemic countries with limited research facilities and resources. In this study, we applied a simple and rapid method for the detection of Schistosoma haematobium and Schistosoma mansoni PCR amplified DNA products using oligochromatographic (OC) dipstick. The amplicons are visualized by hybridization with a gold conjugated probe, while a control for the chromatographic migration is incorporated in the assay. The lower detection limit observed was 10fg of genomic DNA from each of the two species, while the dipstick was also specific for each of the species used in this study.
Assuntos
DNA de Helmintos/análise , Técnicas de Diagnóstico Molecular/métodos , Parasitologia/métodos , Reação em Cadeia da Polimerase , Schistosoma haematobium/isolamento & purificação , Schistosoma mansoni/isolamento & purificação , Esquistossomose/diagnóstico , Animais , DNA de Helmintos/genética , Técnicas de Diagnóstico Molecular/economia , Parasitologia/economia , Sensibilidade e EspecificidadeRESUMO
This study describes the use of cyclodextrins (CDs) as a finishing agent of polyamide (PA) fibers used in order to obtain inguinal meshes with improved antibiotic delivery properties. The finishing process involved polymerization between citric acid and CDs, which yielded a cross-linked polymer that physically adhered to the surface of PA fibers. This permanent functionalization was characterized by evaluating the damping property with a polar liquid (glycerol) via the drop contact angle method for various rates of modification of the fabrics. The biological and microbiological effects of the PA, which were functionalized with hydroxypropylated derivate of gamma-CD (HP-gamma-CDs) and charged with ciprofloxacin (CFX), were evaluated by cell culture assays. We observed a good adhesion and proliferation of fibroblastic cells (NIH3T3) after 3 and 6 days and no detectable toxicity of the modified substrate. The in vitro antibacterial activity of the HP-gamma-CD grafted PA fabrics charged with CFX against the bacteria Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli was greatly superior to that of the virgin sample within a 24h batch experiment in human blood plasma medium. In conclusion, these results from our study offer an insight into the efficient performance of CDs as drug delivery systems for multiple applications in the fields of biomaterials and medical textiles.
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Ciclodextrinas/administração & dosagem , Implantes de Medicamento/administração & dosagem , Implantes de Medicamento/química , Bactérias Gram-Negativas/efeitos dos fármacos , Canal Inguinal , Nylons/química , Telas Cirúrgicas , Antibacterianos/administração & dosagem , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Bactérias Gram-Negativas/citologia , Humanos , Teste de MateriaisAssuntos
Países em Desenvolvimento , Mortalidade Materna/tendências , Modelos Estatísticos , Estatística como Assunto/normas , Adulto , Viés , Burkina Faso , Causas de Morte/tendências , Comparação Transcultural , Coleta de Dados/normas , Atestado de Óbito , Feminino , Previsões , Humanos , Recém-Nascido , Gravidez , Análise de Regressão , Planejamento Social , Incerteza , Nações Unidas/estatística & dados numéricosRESUMO
The hyaluronan production by three human malignant mesothelioma cell lines and nine primary human mesothelial cell types was determined. The mesothelioma cell lines produced only minute amounts of hyaluronan (less than 0.1 microgram/10(6) cells/48 h) whereas mesothelial cells synthesized large quantities of hyaluronan (10-72 micrograms/10(6) cells/48 h). Conditioned media from the mesothelioma cell lines were investigated for their ability to stimulate hyaluronan production by fibroblasts and mesothelial cells in vitro, and in all cases stimulatory effects were found. The factor(s) in the conditioned medium of the mesothelioma cell line Mero-25 that were responsible for hyaluronan stimulation were heat stable and partially trypsin resistant. The stimulatory activity was partially inhibited by an antiserum against platelet-derived growth factor and basic fibroblast growth factor. Our data suggest that the increased hyaluronan synthesis seen in patients with mesothelioma is due to the release of factors from mesothelioma cells that stimulate other cells to produce hyaluronan.
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Ácido Hialurônico/metabolismo , Mesotelioma/metabolismo , Meios de Cultura/análise , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fibroblastos/metabolismo , Humanos , Técnicas In Vitro , Fator de Crescimento Derivado de Plaquetas/metabolismo , Células Tumorais CultivadasRESUMO
A method is reported for the measurement of the diffusion coefficients in water of some sparingly soluble gases. The results obtained for the diffusion coefficients of oxygen and nitrogen gas through water at 25 degrees C are 2.12. 10-5 and 2.61 . 10-5 cm-2 . s-1, respectively. A check on the accuracy of the teachnique using tritiated water as the diffusing substance gave a value of 2.15 . 10-5 cm-2 . s-1 which agrees within 3% with recent values from the literature. The method was applied to the measurement of oxygen, nitrogen, and tritiated water diffusion coefficients through agarose gels and through agarose gels containing hyluronate. The results indicate that the hyaluronate had only a small effect as a barrier to the diffusion of such low molecular weight substance.
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Ácido Hialurônico , Nitrogênio , Oxigênio , Difusão , Eletrodos , Cinética , Matemática , Sefarose , Temperatura , ÁguaRESUMO
The lipopolysaccharide (LPS) is up to now the only identified major virulence determinant of Brucella. This bacterium is responsible for brucellosis in animals and for Malta fever in humans. Several monoclonal antibodies (mAbs) directed against various LPS epitopes have been characterized. Two mAbs, named A15-6B3 and B66-2C8, directed against distinct LPS epitopes have been used to select peptides from 11 phage display libraries. The sequences of the selected peptides contain an overrepresentation of either proline or tryptophan residues when selected with either A15-6B3 or B66-2C8 mAbs, respectively. For the best binding peptides, competition with LPS for the binding to the mAb is detected, which suggests that the peptides bind to the paratope of the mAb. The phages selected from the libraries were used to immunise mice, and a weak antibody response directed against LPS has been observed. These data suggest that a subset of the selected peptides are mimotopes of the LPS epitopes.
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Antígenos de Bactérias/imunologia , Brucella/imunologia , Epitopos , Lipopolissacarídeos/imunologia , Mimetismo Molecular , Peptídeos/imunologia , Sequência de Aminoácidos , Animais , Ensaio de Imunoadsorção Enzimática , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Biblioteca de Peptídeos , Prolina/imunologia , Seleção Genética , Triptofano/imunologia , VacinaçãoRESUMO
The diffusion of fluorescein isothiocyanate-labelled dextran molecules in suspensions of centrifugally, tightly packed, erythrocyte ghosts was measured by fluorescence recovery after photobleaching. In comparison with diffusion in aqueous solution, the diffusion coefficients for probe molecules of varying size were about two orders of magnitude smaller. It was established that the dextran molecules remained in the space between the ghosts. Since crosslinking membrane surface carbohydrates with antibodies further inhibits diffusion, it is assumed that interactions between surface carbohydrates and the probe molecules are the cause of slow diffusion. Two alternative models are discussed.
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Carboidratos/sangue , Dextranos/sangue , Membrana Eritrocítica/metabolismo , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceínas/sangue , Anticorpos , Antígenos de Grupos Sanguíneos/imunologia , Difusão , Corantes Fluorescentes , Humanos , FotoquímicaRESUMO
Hyaluronan (HYA) is a large glycosaminoglycan with a high capacity to immobilize water. Increased levels of HYA have previously been observed in plasma as well as in affected tissues in various inflammatory conditions. The morphological localization of HYA has, however, not been described in normal or rejected human kidneys. Using a recently developed method for localization of HYA in tissue sections by means of a biotin-labeled hyaluronan binding protein used as a probe, we have now investigated the distribution of HYA in normal and irreversibly rejected human kidneys. In the normal kidney HYA was essentially confined to the medulla. In the rejected kidneys increased amounts of HYA were observed primarily in the cortex and in sclerotic vessels. Incubating tissue sections with hyaluronidase abolished the staining for HYA, showing the specificity of the staining procedure. The increased amounts of HYA of the rejected kidney may play a role in local edema formation, and thereby alter graft function.
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Ácido Hialurônico/metabolismo , Transplante de Rim/patologia , Rim/metabolismo , Tecido Conjuntivo/metabolismo , Rejeição de Enxerto , Histocitoquímica , HumanosRESUMO
The glycosaminoglycan hyaluronan is not only involved in cellular differentiation and migration but may also play a role in several inflammatory diseases. We have previously demonstrated an increased local production of hyaluronan in chronically rejected kidneys and the correspondingly affected renal vessels. In this report, we demonstrate the presence of hyaluronan in acutely rejecting kidneys. A total of 77 biopsies classified as either acute rejection or nonrejecting were analyzed using a biotin-labeled hyaluronan-binding protein in conjunction with an avidin-biotin peroxidase detection system and graded using an arbitrary scale from 0 to 3. Those biopsies classified as nonrejecting did not contain any peritubular hyaluronan in the cortex, with hyaluronan being localized only in the medulla. In contrast, those biopsies exhibiting acute rejection had an increase of hyaluronan both in the cortex and in the medulla. This increase was significantly different (P = 0.0001) and correlated with edema and interstitial inflammation. The detection of the local hyaluronan production may be a useful marker to measure acute rejection episodes.
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Ácido Hialurônico/metabolismo , Transplante de Rim , Doença Aguda , Biópsia , Tecido Conjuntivo/metabolismo , Rejeição de Enxerto , Humanos , Rim/metabolismo , Estudos RetrospectivosRESUMO
Accumulation of hyaluronan has previously been observed in various organs as an inflammatory response. To study the presumed connection between infertility due to a tubal factor and inflammation, we performed an analysis of the hyaluronan distribution in biopsy specimens from the female reproductive tract, using a biotinylated hyaluronan binding protein (HABP) as a histochemical probe. In normal specimens hyaluronan was localized in the dense, irregular connective tissue surrounding blood vessels of various sizes. Smooth muscle and columnar epithelium were devoid of hyaluronan. The isthmic part of the normal Fallopian tube showed moderately intense staining of the entire lamina propria, whereas normal fimbriae stained weakly. No cyclic changes in hyaluronan content were observed. In biopsy specimens from women with infertility due to a tubal factor, intense staining, stronger than in normal tubes, was detected in the adhesions and in the lamina propria of sactosalpinx. This may indicate that infertility due to a tubal factor is associated with an ongoing inflammatory and/or proliferative process.
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Endométrio/química , Tubas Uterinas/química , Ácido Hialurônico/análise , Biópsia , Divisão Celular/fisiologia , Endométrio/citologia , Doenças das Tubas Uterinas/metabolismo , Doenças das Tubas Uterinas/patologia , Tubas Uterinas/citologia , Feminino , Histocitoquímica , Humanos , Infertilidade Feminina/metabolismo , Infertilidade Feminina/patologia , Aderências Teciduais/metabolismo , Aderências Teciduais/patologiaRESUMO
Panning and screening of various phage display libraries with monoclonal antibodies (mAbs) directed against the O-chain of the lipopolysaccharide (LPS) of Brucella sp. allowed the identification of peptidic mimotopes of some O-chain epitopes. Four mAbs were tested. The A76-12G12 mAb, which is specific for LPS of all strains of Brucella, either A- or M-dominant, did not yield any peptidic mimotope, despite a specific yield enrichment during the rounds of panning. The B66-4F9 mAb, that recognises an epitope common to both Brucella sp. and Yersinia enterocilitca O:9 strains, allowed the selection of only one phage clone that was shown to be an antigenic but not immunogenic mimotope. The B66-2C8 and A15-6B3 mAbs, respectively, specific for the LPS of A-dominant and M-dominant Brucella sp., yielded several sequences, which allowed the determination of consensus sequences. These consensus will be of high interest for the construction of second generation libraries. For the best binding peptides, competition with LPS for the binding to the mAb is detected, which suggests that the peptides bind to the paratope of the mAb. The phages selected from the libraries were used to immunise mice, and a weak antibody response directed against LPS has been observed for some peptides. These data suggest that a subset of the selected peptides are immunogenic mimotopes of the LPS epitopes.
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Anticorpos Monoclonais/imunologia , Brucella/imunologia , Lipopolissacarídeos/imunologia , Peptídeos/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/biossíntese , Epitopos/imunologia , Feminino , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Mimetismo Molecular , Dados de Sequência Molecular , Antígenos O/imunologia , Biblioteca de Peptídeos , Peptídeos/química , Yersinia enterocolitica/imunologiaRESUMO
The production of cytotoxic oxygen radicals by activated granulocytes is a proposed mechanism of lung injury in ARDS. Protective effects of N-acetylcysteine (NAC) have been described in experimental and clinical ARDS. NAC could act in part by replenishing the intracellular stores of glutathione (GSH) in activated granulocytes, leading to detoxification of oxygen radicals produced by these cells. To test this hypothesis, 16 patients in the early phase of ARDS were randomized to receive either NAC (n = 8) or placebo (n = 8); granulocyte GSH, granulocyte oxygen radical production, and plasma levels of granulocyte elastase were measured in blood samples drawn sequentially within 8 h after the onset of ARDS (day 0), and then 24 (day 1), 72 (day 3), and 120 h (day 5) after the first sample; treatment with NAC or placebo was started immediately after day 0 and stopped just after day 3. Granulocyte GSH was significantly higher on days 1 and 3 when NAC was received by the patient. Unstimulated oxygen radical production, as measured ex vivo by luminol- and lucigenin-amplified chemiluminescence (CL), was higher in granulocytes from ARDS patients than from healthy control subjects, but was not influenced by NAC. The plasma levels of granulocyte elastase were five to eight times above the upper normal limit on day 0, decreased steadily until day 5, and were uninfluenced by NAC. In summary, parenteral NAC treatment started within 8 h of diagnosis increases the intracellular GSH in the granulocytes of ARDS patients without decreasing spontaneous oxidant production by these cells. The mechanisms of the protective effects of this drug previously reported in experimental and clinical ARDS remain to be established.
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Acetilcisteína/uso terapêutico , Antioxidantes/metabolismo , Granulócitos/metabolismo , Oxidantes/metabolismo , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/metabolismo , Acetilcisteína/administração & dosagem , Acridinas , Método Duplo-Cego , Feminino , Glutationa/metabolismo , Granulócitos/efeitos dos fármacos , Granulócitos/enzimologia , Humanos , Indicadores e Reagentes , Infusões Intravenosas , Elastase de Leucócito , Medições Luminescentes , Luminol , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/sangue , Placebos , Espécies Reativas de Oxigênio/metabolismoRESUMO
The effects of increased hydrostatic pressure on the concentrations of hyaluronan (hyaluronic acid) in lung lymph and serum were investigated in awake sheep with a cannula in the efferent vessel from the caudal mediastinal lymph node. Lung lymph was sampled at base line [left atrial pressure (LAP) 6.5 +/- 1.7 mmHg] and after two increases of LAP to 25.7 +/- 2.2 mmHg (level 1) and 37.0 +/- 5.1 mmHg (level 2). The lung lymph flow increased from 1.9 +/- 0.5 at base line to 9.3 +/- 2.2 and 15.9 +/- 0.7 ml/30 min, and the lymph-to-plasma concentration ratio of total protein decreased from 0.63 +/- 0.02 to 0.32 +/- 0.04 and 0.32 +/- 0.05 at the two elevated levels of LAP, respectively. The hyaluronan concentration in lung lymph was unchanged, and there was a flow-dependent elimination of hyaluronan from the lung that increased from 23 +/- 8 to 87 +/- 19 and 137 +/- 37 micrograms/30 min, respectively. The lung concentration of hyaluronan was 167 +/- 28 micrograms/g fresh lung, and at base line it was calculated that slightly less than 2% of the lung hyaluronan was eliminated by the lymphatic route in 24 h. If extrapolated to 24 h, the elimination rate of hyaluronan seen during elevated LAP would result in lymphatic elimination of 18% of the lung hyaluronan over this time period. Since hyaluronan is responsible for part of the protein exclusion in the extracellular matrix, it is plausible that washout of interstitial hyaluronan contributes to the decrease in albumin exclusion from the interstitium that occurs after an elevation of LAP.
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Ácido Hialurônico/metabolismo , Pulmão/fisiologia , Linfa/fisiologia , Animais , Pressão Sanguínea , Feminino , Pressão Hidrostática , Pulmão/citologia , Linfonodos/fisiologia , Masculino , OvinosRESUMO
Hyaluronan influences lung fluid balance. The clearance of lung hyaluronan by way of the pulmonary lymphatics and the pleural space is increased when fluid flux into the interstitium is increased. The purpose of this study was to determine the rate at which hyaluronan is removed from the pleural space. We injected hyaluronan, labeled with tritium in the acetyl group, into the pleural space of six rabbits. The appearance of [3H]H2O in serum was measured over time to calculate the turnover rate of hyaluronan. We found that the half-lives ranged between 8 and 15 h and were positively related to the amount of hyaluronan injected. At the end of the experiment, the contralateral pleural space was irrigated to determine the amount of pleural space hyaluronan, which was 0.3 micrograms/kg body wt.