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1.
J Environ Manage ; 365: 121660, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38963965

RESUMO

- The sediment transport plays a major role in every aquatic ecosystem. However, the lack of instruments to monitor this process has been an obstacle to understanding its effects. We present the design of a single sensor built to measure water velocity, suspended sediment concentration and depth in situ, and how to associate the three variables to estimate and analyse sediment transport. During the laboratory calibrations, the developed instrument presented a resolution from 0.001 g/L to 0.1 g/L in the 0-12 g/L range for the measurement of suspended sediment concentration and 0.05 m/s resolution for 0-0.5 m/s range and 0.001 m/s resolution for 0.5-1 m/s range for the measurement of water velocity. The device was deployed for 6 days in an estuarine area with high sediment dynamics to evaluate its performance. During the field experiment, the sensor successfully measured the tidal cycles and consequent change of flow directions, and the suspended sediment concentration in the area. These measurements allowed to estimate water discharge and sediment transport rates during the different phases of tides, and the daily total volume of water and total amount of sediment passing through the estuary.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Sedimentos Geológicos/análise , Monitoramento Ambiental/métodos , Movimentos da Água , Estuários , Ecossistema
2.
Eur Phys J E Soft Matter ; 44(5): 73, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34047867

RESUMO

In this work, different weight contents of as-grown carbon nanofibers (CNFs), produced by chemical vapor deposition, were melt-extruded with polypropylene (PP) and their morphologic, structure and dielectric properties examined. The morphologic analysis reveals that the CNFs are randomly distributed in the form of agglomerates within the PP matrix, whereas the structural results depicted by Raman analysis suggest that the degree of disorder of the as-received CNFs was not affected in the PP/CNF composites. The AC conductivity of PP/CNF composites at room temperature evidenced an insulator-conductor transition in the vicinity of 2 wt.%, corresponding to a remarkable rise of the dielectric permittivity up to [Formula: see text] 12 at 400 Hz, with respect to the neat PP ([Formula: see text] 2.5). Accordingly, the AC conductivity and dielectric permittivity of PP/CNF 2 wt.% composites were evaluated by using power laws and discussed in the framework of the intercluster polarization model. Finally, the complex impedance and Nyquist plots of the PP/CNF composites are analyzed by using equivalent circuit models, consisting of a constant phase element (CPE). The analysis gathered in here aims at contributing to the better understanding of the enhanced dielectric properties of low-conducting polymer composites filled with carbon nanofibers.

3.
Sensors (Basel) ; 20(11)2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32512850

RESUMO

A cost-effective optical instrument for continuous in-situ monitoring applications is presented. With a production cost in raw materials of 38 €, a power consumption of 300 A in sleep mode and 100 mA in active mode (5 ms reading), and a capacity to monitor turbidity and sedimentary displacement at eight different depths in the water column, the sensor was developed for sediment monitoring in coastal areas. Due to the extent and dynamics of the processes involved in these areas, observations require a wide spatial and temporal resolution. Each of the eight monitoring nodes uses one infrared backscatter channel, to estimate turbidity and sediment concentration, and one ultraviolet with one infrared transmitted light channels to distinguish organic/inorganic composition of the suspended material load. An in-lab calibration was conducted, using formazine to correlate turbidity with the electronic outputs of the instrument. An analysis of the influence of external light sources and correction techniques were performed. Moreover, an in-lab experiment was conducted to study the behaviour of the sensor-to-sediment transport, wash load and sediment accumulation. The device was deployed, with a water level sensor, in an estuarine area with high sediment dynamics. The monitoring data were analysed, showing the potential of the device to continuously monitor turbidity, sediment processes, and distinguish between organic and inorganic matter, at the different depths in the water column.

4.
Sensors (Basel) ; 19(20)2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31614983

RESUMO

A cost-effective optical sensor for continuous in-situ monitoring of turbidity and suspended particulate matter concentration (SPM), with a production cost in raw materials less than 20 €, is presented for marine or fluvial applications. The sensor uses an infrared LED and three photodetectors with three different positions related to the light source-135º, 90º and 0º-resulting in three different types of light detection: backscattering, nephelometry and transmitted light, respectively. This design allows monitoring in any type of environment, offering a wide dynamic range and accuracy for low and high turbidity or SPM values. An ultraviolet emitter-receiver pair is also used to differentiate organic and inorganic matter through the differences in absorption at different wavelengths. The optical transducers are built in a watertight structure with a radial configuration where a printed circuit board with the electronic signal coupling is assembled. An in-lab calibration of the sensor was made to establish a relation between suspended particulate matter (SPM) or the turbidity (NTU) to the photodetectors' electrical output value in Volts. Two different sizes of seashore sand were used (180 µm and 350 µm) to evaluate the particle size susceptibility. The sensor was tested in a fluvial environment to evaluate SPM change during sediment transport caused by rain, and a real test of 22 days continuous in-situ monitoring was realized to evaluate its performance in a tidal area. The monitoring results were analysed, showing the SPM change during tidal cycles as well as the influence of the external light and biofouling problems.

5.
J Hum Nutr Diet ; 27 Suppl 2: 301-12, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23790128

RESUMO

BACKGROUND: The present study aimed to investigate the relationship between adiponectinaemia and food intake among obese women with nonalcoholic fatty liver disease (NAFLD). METHODS: In total, 60 obese women were examined by abdominal ultrasound for liver steatosis and subcutaneous and visceral adiposity. A standard interview (including questions about alcohol intake, medical history and physical activity), a physical examination (including height, weight, body mass index, waist and hip circumferences, waist-to-hip ratio, and body composition) and biochemical and clinical parameters (including serum glucose and insulin, homeostatic model assessment insulin resistance, lipid profile, aminotransferases, C-reactive protein, adiponectin, leptin, resistin, tumour necrosis factor-α, interleukin-6 levels and blood pressure) were performed. Food intake was evaluated by a qualitative food frequency questionnaire. RESULTS: Twenty-four NAFLD patients and thirty-six controls were analysed. The Mann-Whitney test showed lower adiponectin levels in the liver disease group compared to controls (P < 0.05). The Pearson correlation coefficient indicated that adiponectinaemia was negatively correlated with lipid profile and serum tumour necrosis factor-α (P = 0.05) and was positively associated with adiposity measures and serum leptin (P < 0.05). By simple linear regression, all of these variables predicted serum adiponectin levels. Chi-squared and Fisher's exact tests indicated that, in both groups, food intake showed no differences, although sucrose and fatty foods were associated with lower adiponectin levels in the liver disease group (P < 0.05 and P < 0.05, respectively), as well as in the control group (P = 0.05 and P < 0.05, respectively). CONCLUSIONS: Hypoadiponectinaemia in NAFLD was associated with dietary sucrose and fatty food intake, emphasising the important role of diet in the occurrence of this disease.


Assuntos
Adiponectina/sangue , Gorduras na Dieta/administração & dosagem , Sacarose Alimentar/administração & dosagem , Hepatopatia Gordurosa não Alcoólica/sangue , Obesidade/sangue , Adulto , Glicemia/metabolismo , Pressão Sanguínea , Composição Corporal , Estatura , Índice de Massa Corporal , Peso Corporal , Proteína C-Reativa/metabolismo , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Interleucina-6/sangue , Leptina/sangue , Modelos Lineares , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade/complicações , Resistina/sangue , Transaminases/sangue , Fator de Necrose Tumoral alfa/sangue , Circunferência da Cintura , Relação Cintura-Quadril , Adulto Jovem
6.
J Anim Physiol Anim Nutr (Berl) ; 98(5): 948-57, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24304448

RESUMO

Brewer's yeast (BY), autolysed sugarcane yeast (ASCY) and integral sugar cane yeast (ISCY) were studied in two experiments as ingredients for dog diets. In the first experiment, 28 dogs were randomly assigned to four diets; one reference diet and three test diets containing 15% of BY, ASCY or ISCY and 85% of the reference diet (as-fed basis). The digestibilities of the yeasts were calculated by the substitution method. In the second experiment, 35 dogs were randomized to five diets with similar chemical composition but different levels of sugarcane yeast inclusion (0%, 7.5% ASCY, 15% ASCY, 7.5% ISCY and 15% ISCY). In both experiments, the coefficient of total tract apparent digestibility (CTTAD) of nutrients was determined through total collection of faeces. During experiment, two additional analyses of food palatability, nitrogen balance and urea postprandial responses were performed. The data were submitted to analysis of variance, and the means were compared by orthogonal or polynomial contrasts or Tukey's test (p < 0.05). In experiment 1, CTTAD of protein was lower for both sugarcane yeasts than for BY (p = 0.012), as was metabolizable energy content (p = 0.025). In experiment 2, a linear reduction in energy digestibility with ASCY inclusion (p = 0.05) was verified. Furthermore, faecal score and DM content were reduced with ISCY inclusion (p < 0.003). No effect of yeast inclusion on nitrogen balance or postprandial urea response was found. Also, the inclusion of 7.5% of ASCY or ISCY increased diet palatability (p < 0.01). Yeasts present adequate digestibility by dogs, but its effect on faecal formation needs to be considered. No clear advantage for the use of ASCY over ISCY was found. In conclusion, we find that sugarcane yeast is suitable for inclusion in dog food and can enhance the overall palatability of the diet.


Assuntos
Ração Animal/análise , Dieta/veterinária , Proteínas Alimentares/análise , Cães/metabolismo , Saccharomyces cerevisiae/fisiologia , Saccharum/microbiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Proteínas Alimentares/administração & dosagem , Digestão , Cães/sangue , Cães/urina , Metabolismo Energético , Nitrogênio/metabolismo , Saccharomyces cerevisiae/ultraestrutura , Ureia/sangue
7.
Sci Total Environ ; 808: 152164, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-34875333

RESUMO

The sedimentary processes play a major role in every aquatic ecosystem, however, there are few automated options for in-situ monitoring of sediment displacement in the streambed of waterways. We present an automated optical instrument for in-situ continuous monitoring of sediment deposition and erosion of the streambed that requires no calibration. With a production cost of 32€, power consumption of 300 µA in sleep mode, and capacity to monitor the bedform of a waterway, the sensor was developed to evaluate the sediment dynamics of coastal areas with a wide spatial and temporal resolution. The novel device is intended to be buried in the sand and uses 32 infrared channels to monitor the streambed sediment height. For testing purposes, a maximum measuring length of 160 mm and 5 mm resolution was chosen, but these values are scalable. Sensors can be built with different ranges and precision according to the needs of the fieldwork. A laboratory experiment was conducted to demonstrate the working principle of the instrument and its behaviour regarding the turbidity originated by suspended sediment and the settling and deposition of the suspended particles. The device was deployed for 119 days in an estuarine area and was able to detect patterns in the sediment deposition and resuspension during the tidal cycles. Also, abnormal events occurred during the experiment as floods and algae blooms. During these events, the sensor was able to record exceptional erosion and sediment deposition rates. The reported automated instrument can be broadly used in sedimentary studies or management and planning of fluvial and maritime infrastructures to provide real-time information about the changes in the bedform of the watersheds.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Ecossistema , Inundações
8.
Transplant Proc ; 54(5): 1215-1220, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35282887

RESUMO

BACKGROUND: The objective of this study was to map care technologies being developed to improve treatment adherence in patients undergoing organ transplant. METHODS: A scoping review was developed according to the Joanna Briggs Institute manual. The research question was developed according to the population, concept, and context strategy. Searches were conducted independently in 6 databases between June and August 2021. The data were evaluated and organized together. The review protocol was published. RESULTS: Fifteen articles were part of the study, mostly published in the United States (33.3%) and in 2016 (33.3%). The main research method identified was clinical studies (80%). Most of the care technologies identified are in relation to medication adherence in the post-transplant setting. Another intervention identified was health education action with the support of mobile apps, electronic monitoring systems, and a card game. CONCLUSIONS: The results present technologies directed at the importance of post-transplant drug adherence; however, it is important to adapt the technologies to the reality experienced by the patient, as well as to train patients so that they can introduce these technologies in their daily lives. Furthermore, it is important that technologies are developed that include other aspects of adherence to post-transplant treatment.


Assuntos
Transplante de Órgãos , Cooperação e Adesão ao Tratamento , Educação em Saúde , Humanos , Adesão à Medicação , Transplante de Órgãos/efeitos adversos , Projetos de Pesquisa , Estados Unidos
9.
Transplant Proc ; 51(5): 1540-1544, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31155188

RESUMO

OBJECTIVE: The study focuses on the experience of family members of deceased potential donors in deciding to refuse donation when their loved one had expressed his or her wish in life not to donate organs and tissues for transplantation. METHOD: This is a qualitative study that uses social phenomenology as the theoretical reference, interviewing 8 family members of deceased potential donors. RESULTS: The family members' experiences were represented by the following categories: beliefs related to donation, fear in the face of the loved one's death, and the ethical dilemma of deciding to refuse the donation. The meaning of the refusal to donate was represented by the following categories: respect for the loved one's wishes and the family's peace of mind with the decision. CONCLUSIONS: The study shed light on the experience of family members of deceased potential donors in making the decision to refuse donation. The concerns that motivate refusal were elucidated and the meanings of the decision's intentionality were unveiled. The resulting knowledge about these families' experiences provides backing for experts in donation and transplantation who work in different realities, pointing to strategies for improving care for such family members.


Assuntos
Família/psicologia , Doadores de Tecidos/ética , Obtenção de Tecidos e Órgãos/ética , Tomada de Decisões , Feminino , Humanos , Masculino , Princípios Morais , Pesquisa Qualitativa
10.
Transplant Proc ; 50(3): 705-710, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29571742

RESUMO

BACKGROUND: In this study we propose a theoretical and practical basis for the best practices for interviewing relatives of brain-dead eligible organ donors. METHODS: This investigation was a reflective study of the methodologic factors of the family interview that affect their decision regarding the donation of a deceased patient's organs for transplantation. The articles that formed the empirical basis of the trial were obtained from PubMed, which is a free-access tool of the MEDLINE database of the United States National Library of Medicine. Published articles that allowed us to reflect on evidence-based family interview practice were selected. RESULTS: Thirty-six scientific articles were used to guide our assessment the family interview, providing evidence for its adequate execution in view of the following prerequisites: When should the family interview be performed? Where should it be done? How many and which people should participate in the interview? Who should perform it? How should it be done? CONCLUSION: Scientific studies offer evidence to donation and transplantation specialists that can help them in their daily work regarding their interactions with relatives in the process of decisionmaking and family consent.


Assuntos
Prática Clínica Baseada em Evidências , Família/psicologia , Entrevistas como Assunto/métodos , Transplante de Órgãos/psicologia , Doadores de Tecidos/psicologia , Adulto , Morte Encefálica , Tomada de Decisões , Feminino , Humanos , Masculino
11.
Transplant Proc ; 49(4): 756-760, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28457389

RESUMO

BACKGROUND: This study sought to discover the beliefs of nursing professionals in the organ donation process and to establish a relationship between the training and the beliefs of these professionals. METHODS: This was a quantitative and exploratory study composed of 611 nursing professionals. The sample characteristics and the response frequencies were presented through the use of descriptive statistics. The Kruskal-Wallis test was used to evaluate the different results between the professional categories. RESULTS: When evaluating the association between professional nursing, technical and nursing auxiliaries, and beliefs in the donation process, significant differences were found regarding the belief that the transplant improves the quality of life of the recipient, that there is no death while there is a heartbeat, that people are hijacked for organ withdrawal, and that it is possible to buy an organ for transplantation. CONCLUSIONS: For the beliefs presented by nursing professionals, it is evident that there is a need for educational programs to deconstruct negative beliefs and promote change in the professionals' posture.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Enfermeiras e Enfermeiros/psicologia , Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Adulto , Feminino , Humanos , Masculino
12.
Toxicon ; 46(6): 664-71, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16168449

RESUMO

Monoclonal antibodies (mAbs) against Tityus serrulatus venom were obtained by the fusion of SP2/0 murine myeloma cells and spleen cells from BALB/c mice immunized with a toxic fraction (TstFG50) of the Tityus venom (this G50 chromatography fraction represents most of the toxicity of the crude venom) conjugated to bovine serum albumin (BSA) with glutaraldehyde. From the initial screening of over 200 hybridoma fusion wells, a panel of 9 anti-TstFG50 secreting hybridomas was established. The capacity of mAbs to neutralize the TstFG50 toxic fraction toxic was determined by in vitro neutralization assays and by inhibition of the binding of 125I-TsVII to its site on rat brain synaptosomes. Only mAbTs1 neutralized 50% of the toxic effects produced by scorpion venom and showed 35% inhibition of the binding of 125I-TsVII at 10(-7) M. To map the epitope recognized by the protective mAbTs1, we prepared a comprehensive series of overlapping 15-mer synthetic peptides covering the amino acid sequences of the four Tityus proteins. MAbTs1 reacted with peptide 26 of TsIV (KKSKDKKADSGYSYW), peptide 30 of TsVII (KKGSSGYSAWPASYS) and peptide 31 of TsNTxP (KKGSSGYSAWPASYS). MAbTs1 was not reactive with any peptide from TsII. The N-terminal lysine residue from the epitope was found to be critical for mAbTs1 binding. The epitope was positioned on the available three-dimensional structure of TsVII together with the recently identified residues from the pharmacophore of beta-scorpion toxins. The neutralizing properties of mAbTs1 might be explained by spatial vicinity of epitope residues with pharmacophore residues.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Hibridomas/metabolismo , Modelos Moleculares , Venenos de Escorpião/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/metabolismo , Encéfalo/citologia , Linhagem Celular Tumoral , Fracionamento Químico , Ensaio de Imunoadsorção Enzimática , Epitopos/genética , Glutaral , Hibridomas/química , Camundongos , Dados de Sequência Molecular , Testes de Neutralização , Venenos de Escorpião/genética , Venenos de Escorpião/metabolismo , Soroalbumina Bovina , Baço/citologia , Sinaptossomos/metabolismo
13.
Mol Biochem Parasitol ; 55(1-2): 147-53, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1435866

RESUMO

Using nonradioactive hybridization, the human multilocus probe 33.15 was shown to recognize multiple minisatellite regions in nuclear DNA from Trypanosoma cruzi, producing complex banding patterns on Southern blots, typical of DNA fingerprints. The DNA fingerprints were stable and were capable of identifying different strains of the parasite. Individual clones of the Y strain showed different banding patterns, demonstrating that the strain is heterogeneous. In general, the sensitivity and specificity of DNA fingerprinting was similar to that obtained with kinetoplast DNA restriction analysis. However, it has the advantages of being technically simple and of studying nuclear rather than mitochondrial DNA. Thus, it is a useful new tool for the characterization and study of strains and clones of Trypanosoma cruzi.


Assuntos
Impressões Digitais de DNA , DNA de Protozoário/química , DNA Satélite/química , Trypanosoma cruzi/genética , Animais , Southern Blotting , Desoxirribonucleases de Sítio Específico do Tipo II , Hibridização de Ácido Nucleico , Reprodutibilidade dos Testes , Especificidade da Espécie , Trypanosoma cruzi/classificação
14.
Acta Trop ; 61(3): 255-61, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8790775

RESUMO

Salivary gland extract of Triatoma infestans prolonged thrombin time, prothrombin time, and activated partial thromboplastin time, while salivary gland extract of Panstrongylus megistus delayed thrombin time and activated partial thromboplastin time. However, saliva of P. megistus prolonged activated partial thromboplastin time and saliva of T. infestans delayed activated partial thromboplastin time and prothrombin time. T. infestans saliva interferes particularly with activity of factor VIII (intrinsic pathway) and factor V (common pathway), but also affects other factors. Saliva of the triatomine species studied presented distinct SDS-PAGE profiles. These results demonstrate that there are differences in anticoagulant activity and protein composition of triatomine saliva.


Assuntos
Anticoagulantes/farmacologia , Hemípteros/fisiologia , Saliva/fisiologia , Animais , Humanos , Proteínas/análise , Saliva/química
15.
Toxicon ; 35(8): 1229-38, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9278972

RESUMO

Immunoglobulins were isolated from hyperimmune horse plasma against Lachesis muta muta venom by ammonium sulfate precipitation and immunoaffinity technique (Sepharose-venom L. m. muta column). When necessary, limited proteolysis with pepsin was used to generate a bivalent antigen-binding fragment (F(ab')2). Solutions with immunoglobulins or F(ab')2 fragments were fractionated by molecular filtration chromatography (Superose 12) and the expected mol. wt species were observed. The L. m. muta venom shows caseinolytic and haemorrhagic activities. Incubation of the venom with these purified antibodies resulted in a decrease of both activities. High temperatures promote aggregation and the formation of protein precipitates. Sorbitol (1.0 M) was used as an osmolyte (a natural substance or an organic compound capable of stabilizing proteins) and decreased the formation of protein precipitates in solutions of antibodies, as judged by a spectrophotometric assay (280 nm), by nephelometry or when tested by enzyme-linked immunosorbent assay. Circular dichroism was used to study the spectra of antibodies in the presence of phosphate-buffered saline or sorbitol. Up to an osmolyte concentration of 1.0 M, there was no significant perturbation of the F(ab')2 fragments spectra in the amide region. However, whole immunoglobulins in the presence of 1.0 M sorbitol presented a small spectral perturbation, suggesting that the beta-structure was reinforced. The effect of osmolyte on the affinity of antibodies was observed by enzyme-linked immunosorbent assay. There was no significant difference in the results when the antibodies were previously incubated with venom in phosphate-buffered saline or in the presence of 1.0 M sorbitol. In conclusion, an osmolyte (sorbitol) was shown to be capable of stabilizing antibodies at high temperatures, with no significant perturbation in the secondary structure or affinity to L. m. muta venom. These results point to the possibility of using sorbitol, or other osmolytes, as stabilizers of immunoglobulin preparations.


Assuntos
Antivenenos/imunologia , Venenos de Crotalídeos/química , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Imunoglobulinas/isolamento & purificação , Animais , Dicroísmo Circular , Cavalos , Imunoglobulinas/química , Sorbitol , Espectrofotometria Ultravioleta
16.
Toxicon ; 38(1): 139-44, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10669019

RESUMO

One mAb reactive with mutalysin-II, a hemorrhagic metalloproteinase isolated from Lachesis muta muta venom, was produced in mice immunized with L. m. muta venom. Indirect ELISA was employed to compare the antigenic cross-reactivity among the venoms from Bothrops snakes. The mAb anti-mutalysin-II efficiently neutralized the hemorrhagic effect of both mutalysin-II and L. m. muta crude venom. Furthermore, the mAb were cross-reactive with B. alternatus, B. atrox, B. itapetiningae, B. jararaca and B. neuwiedii and showed variable potencies in neutralizing the hemorrhagic activity of several bothropic venoms.


Assuntos
Anticorpos Monoclonais/farmacologia , Bothrops , Venenos de Crotalídeos/antagonistas & inibidores , Venenos de Crotalídeos/toxicidade , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Metaloendopeptidases/antagonistas & inibidores , Venenos de Víboras/antagonistas & inibidores , Venenos de Víboras/toxicidade , Viperidae , Animais , Fusão Celular/efeitos dos fármacos , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Masculino , Metaloendopeptidases/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Baço/citologia
17.
Rev Inst Med Trop Sao Paulo ; 38(1): 39-44, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8762638

RESUMO

Amebiasis continues to be of epidemiological importance in underdeveloped countries. Clinical diagnosis and epidemiological setting in a region are based on the fecal microscopic identification of cysts or trophozoites. This procedure requires well trained personnel, is laborious, of low sensitivity and frequently yields false-positives results. The present study was designed to develop an immunoenzymatic fecal 96 kDa antigen capture test (COPROELISA-Eh) more sensitive and specific than microscopic diagnosis of amebiasis. Triplicates of 177 stool samples processed by the formol-ether concentration method, were defined as positive or negative by three experienced microscopic observers. Another aliquot was submitted to the antigen capture test by a monoclonal antibody against a specific membrane antigen of pathogenic strains of Entamoeba histolytica. Optical densities were interpreted as positive when they exceeded the mean value of negative samples plus two standard deviations. COPROELISA-Eh showed a 94.4% sensitivity, 98.3% specificity, 96.2% positive predictive value and 97.6% negative predictive value for the detection of E. histolytica in feces. COPROELISA-Eh is more sensitive and specific than microscopic examination, does not require specially trained personnel and allows the simultaneous processing of a large number of samples.


Assuntos
Entamoeba histolytica/imunologia , Entamebíase/diagnóstico , Análise de Variância , Animais , Anticorpos Monoclonais/análise , Antígenos de Protozoários/análise , Distribuição de Qui-Quadrado , Entamoeba histolytica/isolamento & purificação , Entamoeba histolytica/patogenicidade , Ensaio de Imunoadsorção Enzimática/métodos , Fezes/parasitologia , Humanos , Técnicas Imunoenzimáticas , Camundongos , Camundongos Endogâmicos BALB C , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Virulência
18.
Rev Inst Med Trop Sao Paulo ; 37(3): 197-200, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8525263

RESUMO

At this moment, the duality of species suggested for E. histolytica is being considered for discussion. In order to contribute to settling this question, we investigated the possibility of conversion of avirulent ameba to virulent ones, as well as, the possibility of increasing virulence of virulent strains, by means of association with bacteria. Five strains of E. histolytica were employed, two of them regarded as avirulent and three virulent ones. Amebas were associated with the bacteria Escherichia coli 055 and 0115, previously demonstrated as capable to modify the pathogenic behavior of E. histolytica. Changes in virulence of amebas were assessed by cytopathic effect upon cultured mammal cells and erythrophagocytosis. The virulence of pathogenic strains was significantly increased after bacteria association in opposition to what was observed for nonpathogenic ones, which were not influenced by bacteria association.


Assuntos
Entamoeba histolytica/patogenicidade , Escherichia coli/patogenicidade , Animais , Chlorocebus aethiops , Cricetinae , Fagocitose , Células Vero/microbiologia , Virulência
19.
Cad Saude Publica ; 10(3): 339-55, 1994 Sep.
Artigo em Português | MEDLINE | ID: mdl-14762543

RESUMO

This article presents data from a study on quality of information from the data bank on the form used in the Brazilian health care system to authorize hospital admittance (AIH). The form pertains to the Unified Health System (SUS) and is used by hospitals to be reimbursed for the health care provided to patients, with public funds. The AIH data bank is the largest source of information in Brazil on production by hospitals. This study analyzes a sample of forms filled out by private hospitals under contract with the city of Rio de Janeiro in 1986. Study design was based on reliability between interviewers, and agreement was analyzed utilizing the kappa test. Agreement was analyzed between data from AIH forms filled out by administrative personnel and information from medical files for patients, focusing on demographic, administrative, and clinical variables. The first two types of variables were generally more reliable than the third. Reliability for the principal diagnosis was worse than for the prescribed procedure, despite the latter being the reference for unit reimbursement by the Unified Health System. Furthermore, where there was disagreement, hospitals were more likely to adopt a procedure with higher reimbursement value as compared to the data derived from the clinical file. The article proposes measures to improve data quality.

20.
Parasite ; 8(2): 99-105, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11474987

RESUMO

With the purpose of establishing alternative parameters to determine the virulence of Toxoplasma gondii strains, the antigenic diversity of eight strains of the parasite isolated in Brazil was evaluated. BALB/c mice were inoculated i.p. with 10(0), 10(1), 10(2) and 10(3) tachyzoites from each strain. The mortality and time to death of the animals showed that T. gondii strains may be divided in three groups: three strains resulted in 100% of mortality, 5-10 days post inoculation (DPI); three strains resulted in 100% of mortality, 7-19 DPI and brain cysts were observed in the mice which were inoculated; two strains resulted in 0% of mortality, 30 DPI. The analysis of the antigenic profile of different T. gondii strains through Western blotting, using rabbit antiserum to T. gondii, revealed that most antigens are similar to all strains. The mAb 4C3H4 recognized antigens only in the RH, N, AS28 and ME49 strains.


Assuntos
Diversidade de Anticorpos , Toxoplasma/patogenicidade , Toxoplasmose/parasitologia , Animais , Western Blotting , Encéfalo/parasitologia , Encefalopatias/parasitologia , Brasil , Cistos/parasitologia , Cães , Eletroforese em Gel de Poliacrilamida , Cabras , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Coelhos , Ovinos , Toxoplasma/imunologia , Toxoplasmose/imunologia
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