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1.
Folia Neuropathol ; 61(2): 153-162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37587890

RESUMO

INTRODUCTION: The aim of the study was to investigate the pathogenesis of diabetic peripheral neuropathy (DPN) and the value of fibrinogen (FIB) in the early diagnosis of DPN. MATERIAL AND METHODS: A total of 121 patients with type 2 diabetes mellitus (T2DM) and DPN hospitalized in the Endocrinology Department of the 923 Hospital of the People's Liberation Army of China were randomly selected between May and October 2020 and divided into a T2DM asymptomatic (no peripheral neuropathy-related symptoms) group (66 cases) and a T2DM symptomatic group (55 cases) according to the presence or absence of clinical neurological symptoms and signs. Forty healthy volunteers were selected as a normal control group. In addition to plasma FIB and nerve electrophysiological tests, all included subjects were electrophysiologically tested for nerve conduction velocity (NCV), terminal motor latency (DML), sensory nerve action potential (SNAP) amplitude, and compound muscle action potential (CMAP) amplitude. RESULTS: Compared with the control group, NCV was slowed down in T2DM patients, DML was prolonged, and the amplitude of CMAP and SNAP were decreased. Compared with asymptomatic T2DM patients, symptomatic patients had slower NCV, longer DML, lower CMAP amplitude of median nerve, ulnar nerve and tibial nerve, and significantly lower SNAP amplitude of median nerve and ulnar nerve. CMAP amplitudes were decreased, and median and ulnar nerve SNAP amplitudes were also significantly decreased ( p < 0.05). The plasma FIB concentration of asymptomatic patients with T2DM was higher than that of the control group, and the plasma FIB concentration of symptomatic patients with T2DM was higher than that of asymptomatic patients with T2DM ( p < 0.01). The NCV and DML of asymptomatic patients with T2DM slowed down and prolonged as the FIB level increased; the NCV of T2DM symptomatic patients also slowed down as FIB increased, and median and ulnar nerve DML increased as FIB increased. There was no correlation between NCV and DML and the plasma FIB level in the control group. SNAP amplitudes of symptomatic and asymptomatic patients with T2DM decreased as plasma FIB increased, while CMAP amplitudes of the tibial nerve and the T2DM symptomatic ulnar nerve decreased as FIB increased in the control group. CONCLUSIONS: FIB may be a contributing factor for diabetic neuropathy and could be used as an indicator in the early screening and diagnosis of peripheral neuropathy in patients with T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Humanos , Fibrinogênio , Neuropatias Diabéticas/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Estudos de Condução Nervosa
2.
Protein Pept Lett ; 30(6): 486-497, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37165590

RESUMO

INTRODUCTION: Diabetic peripheral neuropathy (DN) is the most common complication of type 2 diabetes mellitus (T2DM). OBJECTIVE: This study aimed to explore the role of fibrinogen (FIB) in T2DM neuropathy and its preliminary mechanism. METHODS: Ten male Sprague-Dawley rats were divided into a normal control group (NC group) and a T2DM neuropathy model group (DN group). The DN group was given a high-energy diet and streptozotocin, while the NC group was given a normal diet and a citric acid buffer. The expression levels of related proteins were analysed. RESULTS: Electrophysiology: Compared with the NC group, the conduction latency of the somatosensory-evoked potential and nerve conduction velocity was prolonged in the DN group, while the motor nerve action potential was decreased. As seen under a light microscope, the peripheral nerve fibres in the DN group were swollen, and the nerve fibres in the posterior funiculus of the spinal cord were loose or missing. Moreover, as seen under an electron microscope, the peripheral nerve demyelination of the DN group was severe, with microvascular blood coagulation, luminal stenosis, and collapse. Compared with the NC group, in the DN group, the expression of FIB was positively correlated with the expression of both ionised calcium-binding adaptor molecule-1 and glial fibrillary acidic protein. Compared with the NC group, in the DN group, the expression of platelet/endothelial cell adhesion molecule-1 and B-cell lymphoma 2 was negatively correlated. CONCLUSION: The increased concentration of FIB may be the cause of neuropathy, and its mechanism may be related to its promotion of inflammatory response, blood coagulation, and vascular stenosis.


Assuntos
Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Ratos , Animais , Masculino , Neuropatias Diabéticas/complicações , Diabetes Mellitus Tipo 2/complicações , Fibrinogênio , Constrição Patológica/complicações , Ratos Sprague-Dawley
3.
Physiol Meas ; 41(7): 075009, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32559754

RESUMO

OBJECTIVE: Polysomnography is typically used to evaluate the severity of obstructive sleep apnea (OSA) but the inconvenience of application and high cost considerably affect the diagnostics. In this study, sleep sound signals are used to detect OSA in patients. APPROACH: A deep feature transfer-based OSA detection approach is proposed. First, a deep convolutional neural network is trained on large-scale labeled audio data sets to distinguish respiration sounds from environmental noise. Second, the trained model is transferred to recognize respiration sounds in sleep sound signals. Third, the deep features of the detected respiration sounds are used to train a logistic regression classifier to identify OSA patients from potential patients. Polysomnography-based diagnosis is used as a reference. MAIN RESULTS: A self-collected data set of 132 potential OSA patients is applied in OSA detection experiments. The OSA detection performances are tested on four models for different apnea-hypopnea index thresholds and sexes resulting in accuracies of 80.17%, 80.21%, 81.63% and 77.22%. The corresponding areas under the receiver operating characteristic curves are 0.82, 0.80, 0.81 and 0.79. In addition, the proposed method presented a significant performance improvement compared with the state-of-the-art methods. SIGNIFICANCE: Big data, deep learning and transfer learning can be successfully applied to improve diagnostic accuracy in OSA detection. The performance of the proposed approach is superior to that of traditional audio analysis technology. The proposed method significantly reduces difficulties in OSA detection and diagnosis, such that potential OSA patients can perform initial inspections by themselves at home.


Assuntos
Sons Respiratórios , Processamento de Sinais Assistido por Computador , Apneia Obstrutiva do Sono , Humanos , Redes Neurais de Computação , Polissonografia , Sono , Apneia Obstrutiva do Sono/diagnóstico
4.
Comput Methods Programs Biomed ; 193: 105464, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32283387

RESUMO

BACKGROUND AND OBJECTIVE: Brain-computer interfaces build a communication pathway from the human brain to a computer. Motor imagery-based electroencephalogram (EEG) classification is a widely applied paradigm in brain-computer interfaces. The common spatial pattern, based on the event-related desynchronization (ERD)/event-related synchronization (ERS) phenomenon, is one of the most popular algorithms for motor imagery-based EEG classification. Moreover, the spatiotemporal discrepancy feature based on the event-related potential phenomenon has been demonstrated to provide complementary information to ERD/ERS-based features. In this paper, aiming to improve the performance of motor imagery-based EEG classification in a few-channel situation, an ensemble support vector learning (ESVL)-based approach is proposed to combine the advantages of the ERD/ERS-based features and the event-related potential-based features in motor imagery-based EEG classification. METHODS: ESVL is an ensemble learning algorithm based on support vector machine classifier. Specifically, the decision boundary with the largest interclass margin is obtained using the support vector machine algorithm, and the distances between sample points and the decision boundary are mapped to posterior probabilities. The probabilities obtained from different support vector machine classifiers are combined to make prediction. Thus, ESVL leverages the advantages of multiple trained support vector machine classifiers and makes a better prediction based on the posterior probabilities. The class discrepancy-guided sub-band-based common spatial pattern and the spatiotemporal discrepancy feature are applied to extract discriminative features, and then, the extracted features are used to train the ESVL classifier and make predictions. RESULTS: The BCI Competition IV datasets 2a and 2b are employed to evaluate the performance of the proposed ESVL algorithm. Experimental comparisons with the state-of-the-art methods are performed, and the proposed ESVL-based approach achieves an average max kappa value of 0.60 and 0.71 on BCI Competition IV datasets 2a and 2b respectively. The results show that the proposed ESVL-based approach improves the performance of motor imagery-based brain-computer interfaces. CONCLUSION: The proposed ESVL classifier could use the posterior probabilities to realize ensemble learning and the ESVL-based motor imagery classification approach takes advantage of the merits of ERD/ERS based feature and event-related potential based feature to improve the experimental performance.


Assuntos
Interfaces Cérebro-Computador , Imaginação , Algoritmos , Eletroencefalografia , Humanos , Processamento de Sinais Assistido por Computador , Máquina de Vetores de Suporte
5.
Biomicrofluidics ; 12(5): 054102, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30271517

RESUMO

Recombinant proteins have shown several benefits compared with their non-recombinant counterparts in protein therapeutics. However, there are still some problems with the storage and distribution of recombinant proteins, owing to their temperature sensitivity. Microfluidic chips can integrate different functional modules into a single device because of the advantages of integration and miniaturization, which have the special potential to synthesize drugs when and where they are needed most. Here, we integrated cell-free protein synthesis and purification into a microfluidic chip for the production of recombinant protein. The chip consisted of a main channel and a branch channel. The main channel included two pinches, which were filled with template DNA-modified agarose microbeads and nickel ion-modified agarose beads as the cell-free protein synthesis unit and protein purification unit, respectively. The reaction mixture for protein synthesis was introduced into the main channel and first passed through the protein synthesis unit where the target protein was synthesized; next, the reaction mixture passed through the protein purification unit where the target protein was captured; and, finally, pure protein was collected at the outlet when washing buffer and eluting buffer were sequentially introduced into the branch channel. Enhanced green fluorescent protein (EGFP) was used as the model to investigate the performance of our chip. One chip could produce 70 µl of EGFP solution (144.3 µg/ml, 10.1 µg) per batch, and another round of protein synthesis and purification could be performed after replacing or regenerating nickel ion-modified agarose beads. It should be possible to produce other recombinant proteins on demand with this chip by simply replacing the template DNA.

6.
Pediatr Infect Dis J ; 28(11): 1020-1, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19820428

RESUMO

We conducted a prospective longitudinal study evaluating Candida skin testing among international adoptees presenting to our clinic between 2000 and 2006. Nineteen (17%) and 17 (15%) children had negative tests at presentation and at 6 months, respectively--only 3 were negative at both points. Our study suggests that Candida skin test reactivity is an unstable measure of anergy among international adoptees.


Assuntos
Candidíase/diagnóstico , Testes Cutâneos/métodos , Adoção , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade
7.
Arch Pediatr Adolesc Med ; 163(5): 473-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19414695

RESUMO

OBJECTIVES: To measure the predictive value of immunization records for protective immunity and identify risk factors for immunization failure. DESIGN: Prospective cross-sectional study, 2001-2006. SETTING: International Adoption Clinic, Rainbow Babies and Children's Hospital, Cleveland, Ohio. PARTICIPANTS: A total of 465 international adoptees presenting within 180 days of arrival. Main Exposure Immunization records of vaccines given. OUTCOME MEASURES: Protective immunity to polio, hepatitis B, tetanus, diphtheria, and measles. RESULTS: Vaccination records were available for 397 (85.4%) adoptees (mean age, 19.4 months; 65.2% girls). Most children came from Russia (41.7%), China (20.9%), and Guatemala (15.7%). Acute or chronic malnutrition was present in 5.5% and 15.4% of adoptees, respectively. Preadoptive settings were institutional (52%), community-based (14%), or both (34%). Of adoptees with 3 or more tetanus (n = 203) or 3 or more diphtheria (n = 205) vaccinations, 87.2% and 94.6% had protective immunity, respectively. Of adoptees with 3 or more polio vaccinations (n = 216), protective immunity was present in 58.3%, 82.4%, and 51.9% for polio types 1, 2, and 3, respectively. Of adoptees with 2 or more hepatitis B vaccinations (n = 170), 94.1% had protective immunity. A total of 80.8% of adoptees with measles vaccination (n = 99) had protective immunity. Children from China were less likely to have protective immunity than children from Russia (odds ratio, 0.34; 95% confidence interval, 0.17-0.66). Nutritional status had no predictive effect. CONCLUSIONS: The predictive value of immunization records in international adoptees is limited and varies between birth countries. Immunization records should not be accepted as evidence of protective immunity. Parents should be well informed and supported to choose between revaccination or vaccination, based on serologic testing.


Assuntos
Adoção , Difteria/imunologia , Hepatite B/imunologia , Imunização , Sarampo/imunologia , Prontuários Médicos , Poliomielite/imunologia , Tétano/imunologia , Criança , Pré-Escolar , China/etnologia , Estudos Transversais , Feminino , Guatemala/etnologia , Humanos , Lactente , Masculino , Estado Nutricional , Estudos Prospectivos , Fatores de Risco , Federação Russa/etnologia , Estados Unidos
8.
Sleep ; 32(2): 200-4, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19238807

RESUMO

INTRODUCTION: Extremes of sleep duration have been associated with adverse health outcomes. The mechanism is unclear but may be related to increased inflammation. We sought to assess the association between sleep duration and inflammatory biomarkers. METHODS: A total of 614 individuals from the Cleveland Family Study completed questionnaires about sleep habits and underwent polysomnography. A morning fasting blood sample was assayed for 5 inflammatory cytokines. RESULTS: In this cohort, mean (SD) habitual sleep duration based on self-report was 7.6 (1.6) h and mean sleep duration by polysomnography (PSG) on the night prior to blood sampling was 6.2 (1.3) h. After adjusting for obesity and apnea severity, each additional hour of habitual sleep duration was associated with an 8% increase in C-reactive protein (CRP) levels (P=0.004) and 7% increase in interleukin-6 (IL-6) levels (P=0.0003). These associations were independent of self-reported sleepiness. In contrast, PSG sleep duration was inversely associated with tumor necrosis factor alpha (TNFa) levels. For each hour reduction in sleep, TNFalpha levels increased by 8% on average (P=0.02). Sleep duration was not associated with IL-1 or IL-10. CONCLUSIONS: Increases in habitual sleep durations are associated with elevations in CRP and IL-6 while reduced PSG sleep duration is associated with elevated TNFa levels. Activation of pro-inflammatory pathways may represent a mechanism by which extreme sleep habits affect health.


Assuntos
Distúrbios do Sono por Sonolência Excessiva/imunologia , Mediadores da Inflamação/sangue , Polissonografia , Apneia Obstrutiva do Sono/imunologia , Privação do Sono/imunologia , Adulto , Proteína C-Reativa/metabolismo , Estudos de Coortes , Distúrbios do Sono por Sonolência Excessiva/genética , Feminino , Inquéritos Epidemiológicos , Humanos , Interleucina-1/sangue , Interleucina-10/sangue , Interleucina-6/sangue , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/genética , Obesidade/imunologia , Fenótipo , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/genética , Privação do Sono/genética , Fator de Necrose Tumoral alfa/sangue
9.
Sleep Breath ; 11(4): 285-93, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17440761

RESUMO

Insufficient sleep may lead to adverse health effects, influencing body weight. This study quantified the prevalence of short sleep and the association between sleep duration and overweight in a sample of suburban students. Cross-sectional study was conducted in 2004, involving 529 students from Bay High School, Bay Village, OH, USA, using self-administered questionnaires assessing lifestyle and sleep behaviors. Students with a body mass index Z Score >85th percentile for sex and age were deemed overweight. Ninety percent of students reported average sleep time less than 8 h on school nights, with 19% reported less than 6 h of sleep per night. Twenty percent of the sample were overweight. Overweight was significantly associated with the male gender, increased caffeine consumption, and short sleep duration. Compared with students sleeping >8 h, the age and gender-adjusted odds ratio of overweight was 8.53 (95% CI: 2.26, 32.14) for those with <5 h sleep (P = 0.0036); 2.79 (1.03, 7.55) for those with 5-6 h sleep; 2.81 (1.14, 6.91) for those with 6-7 h sleep; and 1.29 (0.52, 3.26) for those with 7-8 h sleep. Short sleep duration was common and associated with overweight with evidence of a "dose-response" relationship. These results confirm a high prevalence of short sleep among suburban high school students and provide additional support suggesting significant association between short sleeping hours and overweight.


Assuntos
Coleta de Dados , Obesidade/epidemiologia , Sobrepeso , Privação do Sono/epidemiologia , Sono , Estudantes/estatística & dados numéricos , Adolescente , Índice de Massa Corporal , Estudos Transversais , Humanos , Estilo de Vida , Prevalência , Instituições Acadêmicas , Estados Unidos
10.
Environ Health Perspect ; 112(6): 710-6, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15121515

RESUMO

Great Lakes sport-caught fish are contaminated with various organochlorines (OCs) such as polychlorinated biphenyls (PCBs). Through consumption of these fish, humans are subject to continuing levels of OC contamination. To assess potential adverse effects of past exposure, we compared three different backward extrapolation models. The data originated from OC determinations in a cohort of anglers and their families. Repeated PCB measurements collected in the 1970s, 1980s, and 1990s were used when testing the backward extrapolations. We applied a simple and a complex decay model based on assumptions used in previous studies; a third was a regression model incorporating markers of OC intake and loss. These techniques provided past exposure estimates. Intraclass correlation coefficients (ICCs) were calculated comparing measured and estimated PCB values. ICC values for the regression model equations were 0.77 and 0.89; ICC values for the simple and complex decay models were significantly lower, with ranges of 0.07-0.45 and -0.14-0.69, respectively. Plots showing trends of OC concentrations in fish and humans indicate comparable increases and decreases of PCB in fish and humans, with fish concentrations peaking approximately 10 years before that in humans. Our findings suggest that one should be cautious when using simple backward extrapolation techniques to estimate OC exposure in situations involving changing environmental exposures. Whenever repeated measurements are available, regression analyses seem to produce more accurate backward estimations of exposure.


Assuntos
Exposição Ambiental , Peixes , Contaminação de Alimentos , Hidrocarbonetos Clorados , Inseticidas/análise , Inseticidas/farmacocinética , Modelos Teóricos , Adulto , Animais , Aleitamento Materno , Estudos de Coortes , Dieta , Feminino , Great Lakes Region , Meia-Vida , Humanos , Recém-Nascido , Gravidez , Análise de Regressão , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
Environ Health ; 3(1): 1, 2004 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-14748928

RESUMO

BACKGROUND: Studies on maternal exposure to polychlorinated biphenyls (PCBs) reported inconsistent findings regarding birth weight: some studies showed no effect, some reported decreased birth weight, and one study found an increase in weights. These studies used different markers of exposure, such as measurement of PCBs in maternal serum or questionnaire data on fish consumption. Additionally maternal exposures, such as dichlorodiphenyl-dichloroethylene (DDE), which are related to PCB exposure and may interfere with the PCB effect, were rarely taken into account. METHODS: Between 1973 and 1991, the Michigan Department of Community Health conducted three surveys to assess PCB and DDE serum concentrations in Michigan anglers. Through telephone interviews with parents, we gathered information on the birth characteristics of their offspring, focusing on deliveries that occurred after 1968. We used the maternal organochlorine (OC) measurement closest to the date of delivery as the exposure. Although one mother may have contributed more than one child, serum concentrations derived from measurements in different surveys could vary for different children from the same mother. The maternal DDE and PCB serum concentrations were categorized as follows: 0 -< 5 microg / L, 5 -< 15 microg / L, 15 -< 25 microg / L, >or=25 microg / L. Using repeated measurement models (Generalized Estimation Equation), we estimated the adjusted mean birth weight controlling for gender, birth order, gestational age, date of delivery as well as maternal age, height, education, and smoking status. RESULTS: We identified 168 offspring who were born after 1968 and had maternal exposure information. We found a reduced birth weight for the offspring of mothers who had a PCB concentration >or=25 microg / L (adjusted birth weight = 2,958 g, p = 0.022). This group, however, was comprised of only seven observations. The association was not reduced when we excluded preterm deliveries. The birth weight of offspring was increased in women with higher DDE concentrations when controlling for PCBs; however, this association was not statistically significant. CONCLUSION: Our results contribute to the body of evidence that high maternal serum PCB concentration may reduce the birth weight in offspring. However, only a small proportion of mothers may actually be exposed to PCB concentrations >or=25 microg / L.


Assuntos
Peso ao Nascer/efeitos dos fármacos , Diclorodifenil Dicloroetileno/sangue , Diclorodifenil Dicloroetileno/toxicidade , Exposição Materna/efeitos adversos , Bifenilos Policlorados/sangue , Bifenilos Policlorados/toxicidade , Alimentos Marinhos/toxicidade , Poluentes Químicos da Água/toxicidade , Adolescente , Adulto , Animais , Biomarcadores/sangue , Estudos de Coortes , Feminino , Great Lakes Region/epidemiologia , Humanos , Recém-Nascido , Masculino , Idade Materna , Exposição Materna/estatística & dados numéricos , Michigan , Gravidez , Distribuição por Sexo , Inquéritos e Questionários
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