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1.
BJOG ; 127(12): 1548-1556, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32633022

RESUMO

OBJECTIVE: To describe differences in outcomes between pregnant women with and without coronavirus dsease 2019 (COVID-19). DESIGN: Prospective cohort study of pregnant women consecutively admitted for delivery, and universally tested via nasopharyngeal (NP) swab for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using reverse transcription-polymerase chain reaction. All infants of mothers with COVID-19 underwent SARS-CoV-2 testing. SETTING: Three New York City hospitals. POPULATION: Pregnant women >20 weeks of gestation admitted for delivery. METHODS: Data were stratified by SARS-CoV-2 result and symptomatic status, and were summarised using parametric and nonparametric tests. MAIN OUTCOME MEASURES: Prevalence and outcomes of maternal COVID-19, obstetric outcomes, neonatal SARS-CoV-2, placental pathology. RESULTS: Of 675 women admitted for delivery, 10.4% were positive for SARS-CoV-2, of whom 78.6% were asymptomatic. We observed differences in sociodemographics and comorbidities among women with symptomatic COVID-10 versus asymptomatic COVID-19 versus no COVID-19. Caesarean delivery rates were 46.7% in symptomatic COVID-19, 45.5% in asymptomatic COVID-19 and 30.9% in women without COVID-19 (P = 0.044). Postpartum complications (fever, hypoxia, readmission) occurred in 12.9% of women with COVID-19 versus 4.5% of women without COVID-19 (P < 0.001). No woman required mechanical ventilation, and no maternal deaths occurred. Among 71 infants tested, none were positive for SARS-CoV-2. Placental pathology demonstrated increased frequency of fetal vascular malperfusion, indicative of thrombi in fetal vessels, in women with COVID-19 versus women without COVID-19 (48.3% versus 11.3%, P < 0.001). CONCLUSION: Among pregnant women with COVID-19 at delivery, we observed increased caesarean delivery rates and increased frequency of maternal complications in the postpartum period. Additionally, intraplacental thrombi may have maternal and fetal implications for COVID-19 remote from delivery. TWEETABLE ABSTRACT: COVID-19 at delivery: more caesarean deliveries, postpartum complications and intraplacental thrombi.


Assuntos
Betacoronavirus , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , COVID-19 , Teste para COVID-19 , Estudos de Casos e Controles , Cesárea , Estudos de Coortes , Infecções por Coronavirus/complicações , Feminino , Hospitalização , Humanos , Recém-Nascido , Masculino , Cidade de Nova Iorque , Pandemias , Pneumonia Viral/complicações , Gravidez , SARS-CoV-2
2.
Reumatismo ; 72(2): 93-102, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32700875

RESUMO

Rheumatoid arthritis (RA), a form of inflammatory arthritis, is a chronic joint disease characterized by pain and inflammation that affects 0.5% to 1% of the population worldwide. The safety, efficacy, tolerability, and potency of ß-D-mannuronic acid (M2000) as a novel NSAID with immunosuppressive property has been reported by several in vitro studies, experimental models and clinical trials phase I/II and III in ankylosing spondylitis and rheumatoid arthritis (RA) patients This research is designed to study the therapeutic efficacy of oral administration of mannuronic acid in RA patients who had inadequate response to conventional drugs and to assess the effect of this drug on gene expression of the signal transducer and activator of transcription (STATs) protein (STAT1, STAT3, STAT4, and STAT6). The study has included 15 RA patients who had an insufficient response to the conventional therapy. The oral dose of mannuronic acid was 1000mg divided into two 500 mg doses per day for 3 months as an addition to conventional therapy. There were 15 healthy volunteer in the control group. Blood samples were collected from both groups, once from healthy controls and twice from RA patients before and after treatment by M2000. The peripheral blood mononuclear cells (PBMCs) were isolated to assess the gene expression level of STAT1, STAT3, STAT4, and STAT6 using the real-time PCR method. Results obtained in this study demonstrated a significant difference in the gene expression level of STAT1 between healthy controls and patients before treatment as well as a significant reduction in RA patients after treatment compared with the level before treatment. In addition, the gene expression level of STAT3 and STAT4 showed a significant reduction in RA patients after treatment compared to patients before treatment, while there was no significant difference between RA patients before treatment and the healthy control group for both molecules. On the other hand, there was no change in the gene expression level of STAT6 among all groups. The outcomes of this study confirmed that ß-D-mannuronic acid (M2000) has the ability to control the levels of STAT1, STAT3 and STAT4 in RA patients, and might be beneficial in the management and therapy of RA.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Ácidos Hexurônicos/administração & dosagem , Fatores de Transcrição STAT/genética , Transcriptoma/efeitos dos fármacos , Administração Oral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
J Intern Med ; 284(6): 603-619, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30102808

RESUMO

Machine learning (ML) is a burgeoning field of medicine with huge resources being applied to fuse computer science and statistics to medical problems. Proponents of ML extol its ability to deal with large, complex and disparate data, often found within medicine and feel that ML is the future for biomedical research, personalized medicine, computer-aided diagnosis to significantly advance global health care. However, the concepts of ML are unfamiliar to many medical professionals and there is untapped potential in the use of ML as a research tool. In this article, we provide an overview of the theory behind ML, explore the common ML algorithms used in medicine including their pitfalls and discuss the potential future of ML in medicine.


Assuntos
Aprendizado de Máquina , Medicina/tendências , Algoritmos , Sistemas de Apoio a Decisões Clínicas , Previsões , Humanos , Medicina de Precisão , Aprendizado de Máquina Supervisionado , Aprendizado de Máquina não Supervisionado
4.
East Mediterr Health J ; 17(2): 109-14, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21735944

RESUMO

Childhood obesity is a major public health problem globally because of changes in lifestyles. We assessed the prevalence of overweight/obesity and associated factors in urban schoolchildren in Babol in a cross-sectional study of 1000 schoolchildren aged 7-12 years. Weight and height were measured and data on sports activities and leisure time physical activities were collected by questionnaire. Overweight/obesity were assessed by comparing body mass index (BMI) values to the BMI index for age and sex percentiles set by CDC, Atlanta. The prevalence of obesity and overweight was 5-8% and 12.3% respectively. The prevalence was significantly lower in girls compared with boys (age-adjusted OR = 0.69, 95% Cl: 0.50-0.96) and higher among private-school educated children compared with public-school educated students (age adjusted OR = 2.17, 95% Cl: 1.47-3.18). For each additional score of leisure time physical activity, the age-adjusted OR decreased significantly.


Assuntos
Obesidade/epidemiologia , Sobrepeso/epidemiologia , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Prevalência , Fatores de Risco , Instituições Acadêmicas , População Urbana/estatística & dados numéricos
5.
New Microbes New Infect ; 41: 100871, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33777402

RESUMO

We report the first case of the novel coronavirus disease 2019 (COVID-19) presenting with subacute thyroiditis in Ghaemshar, Mazandaran Province, Iran. In our patient, with the initiation of corticosteroid therapy, the symptoms of subacute thyroiditis gradually disappeared with a slow increase in thyroid-stimulating hormone (TSH) and the gradual elimination of thyrotoxicosis. This case shows that decreased TSH and persistent thyrotoxicosis may make the patient's condition worse. Managing this complication can take several weeks and can be complicated.

6.
Immunopharmacol Immunotoxicol ; 32(3): 410-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20233107

RESUMO

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) that leads to an inflammatory demyelination, axonal damage, and progressive neurologic disability that affects approximately 2.5 million people worldwide. The aim of the present research was to test the therapeutic effect of Aloe vera in experimental model of MS. All experiments were conducted on C57BL/6 male mice aged 6-8 weeks. To induce the experimental autoimmune encephalomyelitis (EAE), 250 microg of the myelin oligodendrocyte glycoprotein 35-55 peptide emulsified in complete freund's adjuvant was injected subcutaneously on day 0 over two flank areas. In addition, 200 ng of pertussis toxin in 100 microL phosphate buffered saline was injected intraperitoneally on days 0 and 2. The therapeutic protocol was carried out intragastrically using 120 mg/kg/day Aloe vera from 7 days before to 21 days after EAE induction. The mice were killed 21 days after EAE induction. The brains of mice were removed for histological analysis and their isolated splenocytes were cultured. The results indicated that treatment with Aloe vera caused a significant reduction in severity of the disease in experimental model of MS. Histological analysis showed 3 +/- 2 plaques in Aloe vera-treated mice compared with 5 +/- 1 plaques in control group. The density of mononuclear infiltration in the CNS of Aloe vera-treated mice (500 +/- 200) was significantly less in comparison to 700 +/- 185 cells in control group. Moreover, the serum level of nitric oxide in treatment group was significantly less than control animals. The level of interferon-gamma in cell culture supernatant of treated mice splenocytes was lower than control group, whereas decrease in serum level of interleukin-10 in treatment group was not significant in comparison with control mice. These data indicate that Aloe vera therapy can attenuate the disease progression in experimental model of MS.


Assuntos
Aloe , Encefalomielite Autoimune Experimental/tratamento farmacológico , Esclerose Múltipla/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/patologia , Progressão da Doença , Encefalomielite Autoimune Experimental/patologia , Glicoproteínas/efeitos adversos , Interferon gama/análise , Interleucina-10/sangue , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/patologia , Glicoproteína Mielina-Oligodendrócito , Óxido Nítrico/sangue , Fragmentos de Peptídeos/efeitos adversos , Toxina Pertussis/efeitos adversos , Extratos Vegetais/farmacologia , Índice de Gravidade de Doença , Baço/efeitos dos fármacos , Baço/imunologia
7.
New Microbes New Infect ; 35: 100669, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32322398

RESUMO

Pneumonia appears to be the most common manifestation of coronavirus disease 2019 (COVID-19), but some extrapulmonary involvement, such as gastrointestinal, cardiac and renal, has been reported. The limited clinical data about the virus's behavior to date, especially extrapulmonary symptoms, suggest that we should be aware of the possibility of initial cerebrovascular manifestations of COVID-19.

8.
New Microbes New Infect ; 37: 100732, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32789020

RESUMO

Coronavirus disease 2019 (COVID-19) infection can involve many organs, such as central nervous system, including in relapse. We describe the case of a 64-year-old woman with microbiologically confirmed COVID-19-induced respiratory distress whose treatment resulted in a negative nasopharyngeal swab reverse transcriptase PCR (RT-PCR) result for COVID-19. However, after a few weeks, relapse occurred, as indicated by symptoms of acute meningoencephalitis. Results of COVID-19 RT-PCR testing from her cerebrospinal fluid, nasopharyngeal and tracheal aspiration specimens became positive again, but COVID-19 serum antibodies were negative. We therefore note that symptoms with neurologic involvement can be one of COVID-19's first presentations, or they can appear at relapse. Regular evaluation of patients during convalescence is therefore necessary.

9.
Data Brief ; 22: 1018-1026, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30740487

RESUMO

The presented dataset in this data article provides quantitative data on the production of bioenergy (biogas and biomethane) from mesophilic batch anaerobic digestion (AD) of thermally hydrolyzed organic fraction of municipal solid waste (OFMSW). The discussion and interpretation of the data are provided in another publication entitled "Hydrothermal Pretreatment of Source Separated Organics for Enhanced Solubilization and Biomethane Recovery" (Razavi et al., 2019). The data and information presented in the current data article include (1) the ratio of soluble to particulate chemical oxygen demand (COD) under different thermal hydrolysis condition, (2) the daily measured biogas and biomethane data, (3) the cumulative methane yield data in terms of mL CH4 produced per gram of volatile suspended solids (VSS) as well as feedstock added, (4) the ultimate methane yield data as well as the relative improvement in methane recovery compared to the control (non-hydrolyzed) digester, (5) the data of first-order organics biodegradation rate constants, (6) the procedure of measuring biogas composition via gas chromatography, (7) the procedure of converting the biogas/methane volume data acquired under the actual experimental condition (mesophilic temperature of 38 °C and atmospheric pressure) to the standard temperature (0 °C) and pressure (1 atm) condition, and (8) the procedure of determining the first-order kinetic rate constants.

10.
Bioresour Technol ; 274: 502-511, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30553962

RESUMO

The objective of this research was to evaluate the effect of the hydrothermal pretreatment on the solubilization of source separated organics (SSO) as well as the biomethane recovery through the mesophilic batch anaerobic digestion process. For this purpose, the SSO was subjected to fifteen different pretreatment conditions within five different severity index (SI) values (3, 3.5, 4, 4.5, and 5). The pretreatment temperature, holding time, and pressure ranged from 150 to 240 °C, 5 to 30 min, and 476 to 3367 kPa, respectively. The highest solubilization improvement of ∼50% was achieved under the pretreatment condition of "220 °C-10 min-2323 kPa" corresponding to the SI value of 4.5. However, the maximum biomethane production yield of 280 mL/g TCODadded and biomethane production rate of 30 mL/g TCODadded were obtained under the less intense pretreatment conditions of "190 °C-20 min-1247 kPa" and "170 °C-30 min-786 kPa", respectively.


Assuntos
Metano/biossíntese , Anaerobiose , Temperatura
11.
Environ Toxicol Pharmacol ; 24(1): 60-6, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21783790

RESUMO

UNLABELLED: The present research introduces the method of Production of M2000 (ß-d-mannuronic acid) and its therapeutic effect on experimental model of nephritis. M2000 was produced using enzymatic and chemical procedure on prepared alginate from Pseudomonas fluorescens. The experimental glomerulonephritis was induced in rats by a subcutaneous immunization and daily intravenous administration of bovine serum albumin (BSA). M2000 solution (30mg/kg) was administered intraperitoneally at regular 48-h intervals for 4 weeks. Onset of treatment was day 56. Urinary protein was measured weekly and serum anti-BSA antibody was assessed by ELISA method at different intervals. Animals were killed on day 84 and blood samples and kidney specimens were obtained. Serum (creatinine, BUN, cholesterol, and triglyceride) and urine (protein, urea, and creatinine) determinants were measured at the time of sacrifice. Kidney specimens were processed for light and immunofluorescent microscopic examination. The fibrosarcoma cell line was used for assaying tolerability and matrix metalloproteinase type 2 (MMP-2) activity. MMP-2 activity was assessed using zymography. Our data showed that M2000 therapy could significantly reduce the urinary protein excretion in treated rats versus non-treated controls. Anti-BSA antibody titer was lower in treated rats than in controls at the 12th experimental week. PMN infiltration and glomerular immune complex deposition was less intense in treated rats than in controls. Cytotoxicity analysis of M2000 showed a much higher tolerability compared with other tested drugs (diclofenac, piroxicam and dexamethasone). The inhibitory effect of M2000 in MMP-2 activity was significantly greater than that of dexsamethasone and of piroxicam at a concentration of 200µg/ml. Moreover, the toxicological study revealed that M2000 had no influence on serum (BUN, creatinine, triglyceride and cholesterol) determinants, urinary protein excretion and glomerular histology in healthy group receiving drug. CONCLUSIONS: In this research, for the first time we introduced the procedure of production of M2000 (ß-d-mannuronic acid) and our data suggest that treatment with M2000, as a novel anti-inflammatory drug can reduce proteinuria, diminish antibody production and suppress the progression of disease in experimental model of glomerulonephritis.

12.
Urology ; 5(1): 1-11, 1975 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1090042

RESUMO

A case of innumerable renal artery aneurysms of probable congenital origin is reported. No other lesion could be found in any other abdominal organ studied. We think it unique as no similar case could be found in the medical literature. Except for right flank malaise, the patient was otherwise asymptomatic. The radiologic diagnostic methods are discussed, stressing the differential diagnosis of calcifications in the area of the kidney. The management of renal aneurysms is discussed in regard to the nephrectomy.


Assuntos
Aneurisma , Artéria Renal , Adulto , Aneurisma/diagnóstico por imagem , Aneurisma/epidemiologia , Aneurisma/patologia , Aneurisma/cirurgia , Aortografia , Canadá , Diagnóstico Diferencial , Feminino , Humanos , Técnicas In Vitro , Nefrectomia , Artéria Renal/diagnóstico por imagem , Artéria Renal/patologia , Artéria Renal/cirurgia , Urografia
13.
Artigo em Inglês | MEDLINE | ID: mdl-11209853

RESUMO

Diffuse reflectance spectroscopy has been used to investigate structural modification of mazzite zeolite subjected to calcination, acid leaching and acetylacetone treatments. Extra-framework aluminium species, formed upon expulsion of aluminium from the framework, are detected by DRS because they are involved in aluminium-oxygen charge transfer transitions. Impregnation of the calcined ammonium-exchanged and acid leached samples with ethanolic acetylacetone will convert the broadened 260-280 nm band of extra-framework aluminium with distorted symmetry to a distinct well-defined 285 nm band. The appearance of this band is due to the transformation of the aluminium atoms with a different coordination number to structures with highly ordered octahedral symmetry. Washing the acetylacetone treated samples with hot ethanol leads to extraction of some of the complexed aluminium. The presence of an extracted aluminium triacetylacetonate complex in the eluant is verified by the same spectrophotometer used in its conventional mode. This suggests that a dual DR and UV-VIS spectrophotometry is an appropriate approach to study such topics.


Assuntos
Alumínio/análise , Zeolitas/química , Amônia , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Espectrofotometria/métodos , Espectrofotometria Ultravioleta/métodos
14.
J Biomech ; 44(11): 2021-30, 2011 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-21696742

RESUMO

Symmetrical 30-60% stenosis in a common carotid artery under unsteady flow condition for Newtonian and six non-Newtonian viscosity models are investigated numerically. Results show power-law model produces higher deviations, in terms of velocity and wall shear stress in comparison with other models while generalized power-law and modified-Casson models are more prone to Newtonian state. Comparing separation length of recirculation region at different critical points of cardiac cycle confirms the necessity of considering blood flow in unsteady mode. Increasing stenosis intensity causes flow patterns more disturbed downstream of the stenosis and WSS appear to develop remarkably at the stenosis throat.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Artéria Carótida Primitiva/fisiologia , Estenose das Carótidas/fisiopatologia , Modelos Cardiovasculares , Simulação por Computador , Vasos Coronários/fisiologia , Fluxo Pulsátil/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Reologia/métodos , Resistência ao Cisalhamento/fisiologia , Estresse Mecânico
15.
Transplant Proc ; 43(2): 495-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21440743

RESUMO

BACKGROUND: Cytokine storm generated by an alloimmune response after transplantation can lead to either graft survival or rejection. The aim of this study was to evaluate the serum levels of interleukin (IL)-10, IL-17, transforming growth factor (TGF)-ß1, and interferon (IFN)-γ and expression levels of IL-10 and TGF-ß1 in renal allograft recipients with or without donor bone marrow cell infusion (DBMI). METHODS: We retrospectively followed 28 living unrelated kidney recipients, including 14 with and 14 without DBMI infusion for 2 years. Also, 14 healthy subjects were included as a normal control group. PBMC gene expression analysis for mRNA levels of IL-10 and TGF-ß1 cytokines relative to ß-actin as a reference gene was performed using quantitative fluorescence real-time polymerase chain reaction at the end of 2 years posttransplantation. Also, serum levels of IL-10, TGF-ß1, IFN-γ, and IL-17 in the 3 groups were measured by enzyme-linked immunosorbent assay at the same time. RESULTS: Both patient groups showed increased gene expression and serum content of IL-10 compared with normal controls. The expression levels were only significant between control patients and normal subjects (P=.02). Serum levels of IFN-γ and IL-17 were higher in untreated patients compared with normal controls (P=.03 and P=.07, respectively). DBMI patients showed significantly lower levels of serum TGF-ß1 and IL-17 compared with normal subjects (P=.05 and P=.06, respectively). Also, infused patients showed a positive correlation between circulating levels of IL-17 and IL-10 (r=0.692; P=.006), and an inverse correlation between serum creatinine and TGF-ß1 levels (r=-0.580; P=.03). CONCLUSION: The decreased levels of inflammatory cytokines besides IL-10 with increased TGF-ß1 levels and better allograft function with improved clinical outcomes were observed among infused patients, possibly indicating immunomodulatory effects of this approach in kidney allograft patients.


Assuntos
Regulação da Expressão Gênica , Interferon gama/biossíntese , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Fator de Crescimento Transformador beta1/biossíntese , Adulto , Células da Medula Óssea/citologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Leucócitos Mononucleares/citologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/metabolismo , Estudos Retrospectivos , Transplante Homólogo
17.
Pak J Biol Sci ; 12(2): 146-51, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19579935

RESUMO

Ten wheat lines were studied to determine gene effects and combining ability in some bread wheat genotypes to yellow rust disease. Ten parental lines and F1 were evaluated in a randomized complete block design with three replications in Agricultural and Natural Resources Research Center, Mashhad, Iran. Two races (134E134A+ and 4E0A+) were used for this study. Latent Period (LP) and Infection Type (IT) were measured in the field and greenhouse. Results showed significant differences between races in their pathogenicity and between genotypes in their resistance to the pathogen. Diallel cross carried out between the parents and progenies and thereafter were analyzed by the method of Griffing and Haymans. The General Combining Ability (GCA) and Special Combining Ability (SCA) for all traits were significant and showed additive variance was more important. Test for validity of diallel hypothesis proved epistasis effect for all traits. P1, P2 and F1 showed significant difference between all traits in generations mean analysis. Average degree of dominance ranged from partial to over dominance for resistance or susceptibility. Dominance, additive and epistatic types of gene action were responsible for the genetic control of the traits. However, except for additive-additive component, non-additive effect of genes could not be fixed by self-fertilization.


Assuntos
Basidiomycota/genética , Pão , Imunidade Inata/genética , Doenças das Plantas , Triticum/genética , Agricultura , Basidiomycota/patogenicidade , Cruzamentos Genéticos , Genótipo , Endogamia , Irã (Geográfico) , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Triticum/microbiologia
18.
Biosens Bioelectron ; 24(5): 1298-304, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18801654

RESUMO

The feasibility of a capacitive field-effect EDIS (electrolyte-diamond-insulator-semiconductor) platform for multi-parameter sensing is demonstrated by realising EDIS sensors with an O-terminated nanocrystalline-diamond (NCD) film as transducer material for the detection of pH and penicillin concentration as well as for the label-free electrical monitoring of adsorption and binding of charged macromolecules, like polyelectrolytes. The NCD films were grown on p-Si-SiO(2) substrates by microwave plasma-enhanced chemical vapour deposition. To obtain O-terminated surfaces, the NCD films were treated in an oxidising medium. The NCD-based field-effect sensors have been characterised by means of constant-capacitance method. The average pH sensitivity of the O-terminated NCD film was 40 mV/pH. A low detection limit of 5 microM and a high penicillin G sensitivity of 65-70 mV/decade has been obtained for an EDIS penicillin biosensor with the adsorptively immobilised enzyme penicillinase. Alternating potential changes, having tendency to decrease with increasing the number of adsorbed polyelectrolyte layers, have been observed after the layer-by-layer deposition of polyelectrolyte multilayers, using positively charged PAH (poly (allylamine hydrochloride)) and a negatively charged PSS (poly (sodium 4-styrene sulfonate)) as a model system. The response mechanism of the developed EDIS sensors is discussed.


Assuntos
Técnicas Biossensoriais/instrumentação , Diamante/química , Eletroquímica/instrumentação , Microeletrodos , Nanoestruturas/química , Penicilinase/química , Penicilinas/análise , Transdutores , Técnicas Biossensoriais/métodos , Capacitância Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Membranas Artificiais , Nanoestruturas/ultraestrutura , Penicilinas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Oral Microbiol Immunol ; 22(4): 248-51, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17600536

RESUMO

INTRODUCTION: Enterococci are rarely found in the healthy human oral cavity, yet they are strongly associated with filled root canals. The origin of these enterococci remains unknown. Our hypothesis is that they are transient food-born colonizers under healthy conditions. This pilot study reinvestigated the prevalence of enterococci in the oral cavity of healthy volunteers, screened cheese samples for enterococci and investigated colonization of the oral cavity after ingestion of an enterocci-positive cheese. METHOD: Concentrated oral rinse samples were collected from a cohort of 50 dental students and proved negative for viable enterococci. Twenty cheese samples were obtained from local supermarkets. Enterococci were cultured and identified using standard methods. RESULTS: Viable enterococci were detected in one of five specimens of Swiss Tilsiter, three of five samples of French soft cheese, one of five Mozzarella samples and one of five Feta samples. Eight volunteers from the cohort consumed 10 g of a cheese with high Enterococcus faecalis load. Oral rinse samples were collected before and 1, 10 and 100 min after cheese ingestion. One minute after ingestion, a median of 5,480 E. faecalis colony-forming units was recovered from the oral rinse samples. Bacterial counts were reduced after 10 min, had dropped after 100 min to levels that were significantly (P < 0.005) different from the 1-min and 10-min scores and were below the detection limit after 1 week. CONCLUSIONS: These findings suggest that colonization of the healthy oral cavity by enterococci is transitional, but at the same time add weight to our hypothesis that enterococcal root canal infections could be food-borne.


Assuntos
Queijo/microbiologia , Enterococcus faecalis/isolamento & purificação , Microbiologia de Alimentos , Boca/microbiologia , Adulto , Contagem de Colônia Microbiana , Feminino , Humanos , Masculino , Projetos Piloto
20.
Immunopharmacol Immunotoxicol ; 29(1): 49-61, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17464766

RESUMO

UNLABELLED: The therapeutic efficacy of novel designed nonsteroidal anti-inflammatory drug, M2000 (beta- D- mannuronic acid) on experimental immune complex glomerulonephritis was evaluated. Bovine serum albumin (BSA) nephritis was induced in rats by a subcutaneous immunization and daily intravenous administration of BSA. M2000 solution (30 mg/kg) was administered intraperitoneally at regular 48-hr intervals for 4 weeks. Onset of treatment was day 56. Urinary protein was measured weekly and serum anti-BSA antibody was assessed by ELISA method at different intervals. Animals were killed on day 84 and blood samples and kidney specimens were obtained. Serum (creatinine, blood urea nitrogen, cholesterol, and triglyceride) and urine (protein, urea, and creatinine) determinants were measured at the time of sacrifice. Kidney specimens were processed for light and immunofluorescent microscopic examination. The fibrosarcoma cell line was used for assaying tolerability and matrix metalloproteinase type 2 (MMP-2) activity. MMP-2 activity was assessed using zymography. Our data showed that M2000 therapy could significantly reduce the urinary protein excretion in treated rats versus non-treated controls. Anti-BSA antibody titer was lower in treated rats than in controls at the 12th experimental week. Polymorphonuclear neutrophil leukocytes infiltration and glomerular immune complex deposition were less intense in treated rats than in controls. Cytotoxicity analysis of M2000 showed a much higher tolerability compared with other tested drugs (diclofenac, piroxicam and dexamethasone). The inhibitory effect of M2000 in MMP-2 activity was significantly greater than that of dexsamethasone and of piroxicam at a concentration of 200 microg/ml. Moreover, the toxicological study revealed that M2000 had no influence on serum (BUN, creatinine, triglyceride and cholesterol) determinants, urinary protein excretion and glomerular histology in healthy group receiving drug. CONCLUSIONS: These findings suggest that treatment with M2000 can reduce proteinuria, diminish antibody production, and suppress the progression of disease in a rat model of immune complex glomerulonephritis.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Glomerulonefrite/tratamento farmacológico , Ácidos Hexurônicos/farmacologia , Animais , Complexo Antígeno-Anticorpo/metabolismo , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Glomerulonefrite/sangue , Glomerulonefrite/induzido quimicamente , Glomerulonefrite/patologia , Glomerulonefrite/urina , Metaloproteinase 2 da Matriz/metabolismo , Proteinúria/sangue , Proteinúria/induzido quimicamente , Proteinúria/tratamento farmacológico , Proteinúria/patologia , Proteinúria/urina , Ratos , Ratos Sprague-Dawley , Soroalbumina Bovina/toxicidade
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