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1.
Am J Speech Lang Pathol ; 33(2): 937-951, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38266215

RESUMO

PURPOSE: This study was designed to examine the hypothesis that discourse task types influence language performance in Mandarin Chinese-speaking people and to reveal the discourse task-specific linguistic properties of persons with anomic aphasia compared to neurotypical controls. METHOD: Language samples from persons with aphasia (n = 31) and age- and education-matched controls (n = 31) across four discourse tasks (sequential-picture description, single-picture description, story narrative, and procedural discourse) were collected from Mandarin AphasiaBank. Task-specific distributions of parts of speech were analyzed using mosaic plots. The main effects of tasks in each group and the between-group differences within each task for several typical linguistic variables were evaluated, including the mean length of utterance, tokens, moving-average type-token ratio, words per minute, propositional density, noun-verb ratio, noun percentage, and verb percentage. RESULTS: The results revealed an impact of discourse tasks on most language variables in both groups. In the healthy controls, story narratives yielded the highest total words and lowest verb percentage. In the aphasia group, procedural discourse elicited the fewest total words and densest expressions, whereas their single-picture descriptions had the highest noun-verb ratio. For all tasks, the aphasia group performed worse than the control group in the mean length of utterance, tokens, moving-average type-token ratio, and words per minute. For noun-verb ratio, noun percentage, and verb percentage, only one task (i.e., single-picture description) showed significant between-group differences. CONCLUSION: The selection of discourse tasks should be addressed in assessments and interventions for Mandarin Chinese-speaking individuals with aphasia to obtain more accurate and feasible outcomes.


Assuntos
Anomia , Afasia , Humanos , Linguística , Afasia/diagnóstico , Idioma , China
2.
IEEE Trans Pattern Anal Mach Intell ; 46(6): 4460-4475, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38261485

RESUMO

Noisy labels are often encountered in datasets, but learning with them is challenging. Although natural discrepancies between clean and mislabeled samples in a noisy category exist, most techniques in this field still gather them indiscriminately, which leads to their performances being partially robust. In this paper, we reveal both empirically and theoretically that the learning robustness can be improved by assuming deep features with the same labels follow a student distribution, resulting in a more intuitive method called student loss. By embedding the student distribution and exploiting the sharpness of its curve, our method is naturally data-selective and can offer extra strength to resist mislabeled samples. This ability makes clean samples aggregate tightly in the center, while mislabeled samples scatter, even if they share the same label. Additionally, we employ the metric learning strategy and develop a large-margin student (LT) loss for better capability. It should be noted that our approach is the first work that adopts the prior probability assumption in feature representation to decrease the contributions of mislabeled samples. This strategy can enhance various losses to join the student loss family, even if they have been robust losses. Experiments demonstrate that our approach is more effective in inaccurate supervision. Enhanced LT losses significantly outperform various state-of-the-art methods in most cases. Even huge improvements of over 50% can be obtained under some conditions.

3.
Am J Speech Lang Pathol ; 33(2): 800-813, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38099824

RESUMO

PURPOSE: This study aimed to explore how well persons with anomic aphasia communicate information during discourse regarding quantity, quality, and efficiency compared to neurotypical controls, to investigate the influence of discourse tasks on informativeness and efficiency and to examine impact factors like aphasia severity and cognitive ability. METHOD: Language samples of four discourse tasks from 31 persons with anomic aphasia and 31 neurotypical controls were collected from Mandarin AphasiaBank. Correct information unit (CIU) analysis measures including the total number of CIUs, percentage of CIUs, CIUs per minute, and words per minute were calculated. Group differences and the effects of discourse tasks on informativeness and efficiency were investigated. Correlations of CIU analysis measures with aphasia severity and cognitive ability were examined. RESULTS: Persons with anomic aphasia showed lower efficiency in conveying information than controls. They underperformed controls on all CIU analysis measures when executing story narrative tasks. Discourse tasks influenced the informativeness and efficiency of both groups. Neurotypical controls delivered the greatest quantity of information most efficiently when narrating stories. Persons with anomic aphasia exhibited reduced quantity of information during procedural discourse and displayed superior information quality in sequential-picture descriptions. Discourse information may be impacted by aphasia severity and cognitive ability, with varying effects depending on the task. CONCLUSIONS: Persons with anomic aphasia are inefficient in communicating discourse messages and perform poorly on all measures in story narratives. When measuring discourse information, the effects of discourse tasks and factors like aphasia severity and cognitive ability should be considered.


Assuntos
Anomia , Afasia , Humanos , Anomia/diagnóstico , Afasia/diagnóstico , Afasia/psicologia , Idioma , Narração , Cognição
4.
Entropy (Basel) ; 25(8)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37628265

RESUMO

The variational Bayesian method solves nonlinear estimation problems by iteratively computing the integral of the marginal density. Many researchers have demonstrated the fact its performance depends on the linear approximation in the computation of the variational density in the iteration and the degree of nonlinearity of the underlying scenario. In this paper, two methods for computing the variational density, namely, the natural gradient method and the simultaneous perturbation stochastic method, are used to implement a variational Bayesian Kalman filter for maneuvering target tracking using Doppler measurements. The latter are collected from a set of sensors subject to single-hop network constraints. We propose a distributed fusion variational Bayesian Kalman filter for a networked maneuvering target tracking scenario and both of the evidence lower bound and the posterior Cramér-Rao lower bound of the proposed methods are presented. The simulation results are compared with centralized fusion in terms of posterior Cramér-Rao lower bounds, root-mean-squared errors and the 3σ bound.

5.
Mol Metab ; 73: 101724, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37061130

RESUMO

OBJECTIVE: Obesity in laboratory rodents is generally induced by feeding them a high fat diet (HFD). This model does not permit separation of the impact of the HFD from the resultant obesity on metabolic defects such as impaired glucose homeostasis. In Brandt's voles we have previously shown that exposure to long photoperiod (LD: 16L: 8D) induces obesity even when they are fed a low fat diet. We show here that these voles are largely resistant to HFD. This model therefore permits some separation of the effects of HFD and obesity on glucose homeostasis. The objective was therefore to use this model to assess if glucose homeostasis is more related to diet or obesity METHODS: Male voles, which were 35 days old and born in LD, were exposed to SD and a low fat diet for 70 days. We then randomly separated the animals into 4 groups for another 63 days: SL (short day and low fat diet: n = 19) group; SH (short day and high-fat diet, n = 20) group; LL (long day and low-fat diet, n = 20) group; LH (long day and high-fat diet, n = 18) group. Glucose tolerance tests (GTT) were performed after treatment for 56 days, and body compositions of the voles were quantified at the end by dissection. RESULTS: Consistent with our previous work LD voles were more obese than SD voles. Although total body weight was independent of dietary fat content, HFD did have an effect on fat storage. Photoperiod induced obesity had no effect on glucose homeostasis, and the fat content in both the liver and muscle. In contrast, HFD induced adiposity was linked with elevated fat deposition in muscle (but not in liver) and led to impaired glucose tolerance. CONCLUSIONS: The contrasting effects of diet and photoperiod were consistent with the predictions of the 'lipotoxicity hypothesis'. This may contribute to our understanding of why some human individuals are able to be obese yet remain metabolically healthy.


Assuntos
Dieta Hiperlipídica , Fotoperíodo , Animais , Masculino , Arvicolinae/metabolismo , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Homeostase , Obesidade
6.
Biomolecules ; 13(2)2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36830768

RESUMO

Macrophages play an important role in the progression of sporadic acute type A aortic dissection (ATAAD). The aim of this study was to characterize the cellular heterogeneity of macrophages in ATAAD tissues by scRNA-seq. Ascending aortic wall tissue from six ATAAD patients and three heart transplant donors was assessed by scRNA-seq and then analyzed and validated by various bioinformatic algorithms and histopathology experiments. The results revealed that the proportion of macrophages in ATAAD tissues (24.51%) was significantly higher than that in normal tissues (13.69%). Among the six macrophage subclusters, pro-inflammatory macrophages accounted for 14.96% of macrophages in the AD group and 0.18% in the normal group. Chemokine- and inflammation-related genes (CCL2, CCL20, S100A8, and S100A9) were expressed more intensively in macrophages in ATAAD tissue than in those in normal tissue. Additionally, intercellular communication analysis and transcription factor analysis indicated the activation of inflammation and degradation of the extracellular matrix in ATAAD tissue. Finally, immunohistochemistry, immunofluorescence, and Western blot experiments confirmed the overexpression of macrophage marker genes (CD68 and CD163) and matrix metalloproteinases (MMP9 and MMP2) in ATAAD tissue. Collectively, our study provides a preliminary evaluation of the role of macrophages in ATAAD, and the results could aid in the development of therapeutic options in the future.


Assuntos
Dissecção Aórtica , Análise da Expressão Gênica de Célula Única , Humanos , Aorta , Macrófagos/metabolismo , Inflamação/metabolismo
7.
IEEE Trans Pattern Anal Mach Intell ; 44(12): 8796-8811, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34648433

RESUMO

In partial label learning, a multi-class classifier is learned from the ambiguous supervision where each training example is associated with a set of candidate labels among which only one is valid. An intuitive way to deal with this problem is label disambiguation, i.e., differentiating the labeling confidences of different candidate labels so as to try to recover ground-truth labeling information. Recently, feature-aware label disambiguation has been proposed which utilizes the graph structure of feature space to generate labeling confidences over candidate labels. Nevertheless, the existence of noises and outliers in training data makes the graph structure derived from original feature space less reliable. In this paper, a novel partial label learning approach based on adaptive graph guided disambiguation is proposed, which is shown to be more effective in revealing the intrinsic manifold structure among training examples. Other than the sequential disambiguation-then-induction learning strategy, the proposed approach jointly performs adaptive graph construction, candidate label disambiguation and predictive model induction with alternating optimization. Furthermore, we consider the particular human-in-the-loop framework in which a learner is allowed to actively query some ambiguously labeled examples for manual disambiguation. Extensive experiments clearly validate the effectiveness of adaptive graph guided disambiguation for learning from partial label examples.


Assuntos
Algoritmos , Humanos
8.
Cochrane Database Syst Rev ; 3: CD004434, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33765691

RESUMO

BACKGROUND: Pulmonary arterial hypertension is a devastating disease that leads to right heart failure and premature death. Endothelin receptor antagonists have shown efficacy in the treatment of pulmonary arterial hypertension. OBJECTIVES: To evaluate the efficacy of endothelin receptor antagonists (ERAs) in pulmonary arterial hypertension. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and the reference sections of retrieved articles. The searches are current as of 4 November 2020. SELECTION CRITERIA: We included randomised trials and quasi-randomised trials involving participants with pulmonary arterial hypertension. DATA COLLECTION AND ANALYSIS: Two of five review authors selected studies, extracted data and assessed study quality according to established criteria. We used standard methods expected by Cochrane. The primary outcomes were exercise capacity (six-minute walk distance, 6MWD), World Health Organization (WHO) or New York Heart Association (NYHA) functional class, Borg dyspnoea scores and dyspnoea-fatigue ratings, and mortality. MAIN RESULTS: We included 17 randomised controlled trials involving a total of 3322 participants. Most trials were of relatively short duration (12 weeks to six months). Sixteen trials were placebo-controlled, and of these nine investigated a non-selective ERA and seven a selective ERA.   We evaluated two comparisons in the review: ERA versus placebo and ERA versus phosphodiesterase type 5 (PDE5) inhibitor. The abstract focuses on the placebo-controlled trials only and presents the pooled results of selective and non-selective ERAs. After treatment, participants receiving ERAs could probably walk on average 25.06 m (95% confidence interval (CI) 17.13 to 32.99 m; 2739 participants; 14 studies; I2 = 34%, moderate-certainty evidence) further than those receiving placebo in a 6MWD. Endothelin receptor antagonists probably improved more participants' WHO functional class (odds ratio (OR) 1.41, 95% CI 1.16 to 1.70; participants = 3060; studies = 15; I2 = 5%, moderate-certainty evidence) and probably lowered the odds of functional class deterioration (OR 0.43, 95% CI 0.26 to 0.72; participants = 2347; studies = 13; I2 = 40%, moderate-certainty evidence) compared with placebo. There may be a reduction in mortality with ERAs (OR 0.78, 95% CI 0.58, 1.07; 2889 participants; 12 studies; I2 = 0%, low-certainty evidence), and pooled data suggest that ERAs probably improve cardiopulmonary haemodynamics and may reduce Borg dyspnoea score in symptomatic patients. Hepatic toxicity was not common, but may be increased by ERA treatment from 37 to 67 (95% CI 34 to 130) per 1000 over 25 weeks of treatment (OR 1.88, 95% CI 0.91 to 3.90; moderate-certainty evidence). Although ERAs were well tolerated in this population, several cases of irreversible liver failure caused by sitaxsentan have been reported, which led the licence holder for sitaxsentan to withdraw the product from all markets worldwide.  As planned, we performed subgroup analyses comparing selective and non-selective ERAs, and with the exception of mean pulmonary artery pressure, did not detect any clear subgroup differences for any outcome. AUTHORS' CONCLUSIONS: For people with pulmonary arterial hypertension with WHO functional class II and III, endothelin receptor antagonists probably increase exercise capacity, improve WHO functional class, prevent WHO functional class deterioration, result in favourable changes in cardiopulmonary haemodynamic variables compared with placebo. However, they are less effective in reducing dyspnoea and mortality. The efficacy data were strongest in those with idiopathic pulmonary hypertension. The irreversible liver failure caused by sitaxsentan and its withdrawal from global markets emphasise the importance of hepatic monitoring in people treated with ERAs. The question of the effects of ERAs on pulmonary arterial hypertension has now likely been answered.. The combined use of ERAs and phosphodiesterase inhibitors may provide more benefit in pulmonary arterial hypertension; however, this needs to be confirmed in future studies.


Assuntos
Anti-Hipertensivos/uso terapêutico , Antagonistas dos Receptores de Endotelina/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Viés , Humanos , Hipertensão Pulmonar/mortalidade , Inibidores da Fosfodiesterase 5/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Teste de Caminhada
9.
Urology ; 126: 110-115, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30659900

RESUMO

OBJECTIVE: To evaluate the feasibility and safety of a new laparoscopic technique for resection of a fibrous ring and extravascular stent implantation in patients with nutcracker syndrome (NCS). MATERIAL AND METHODS: We retrospectively reviewed data of 5 patients diagnosed with NCS between March 2010 and February 2016. The mean age of the patients (4 male and 1 female) was 34 years (range, 28-40 years). All 5 patients underwent laparoscopic resection of the narrow fibrous ring around the left renal venous (LRV) and for extravascular stent implantation in the LRV for management of NCS. RESULTS: The average operating time was104 minutes and the average blood loss during surgery was 59 mL. The average length of the postoperative hospital stay was 6 days (range, 4-8 days). In all 5 patients, the symptoms of macroscopic hematuria started decreasing gradually and resolved after surgery. Postoperative computed tomography showed that the blood outflow from the LRV was smooth. The ratio of the dilated segment's inner diameter to the diameter of the strictured segment decreased from 3.4 to 9.5, preoperatively to 1.1-2.0, postoperatively. The mean follow-up period was 17.6 months (range, 8-24 months).One patient's varicocele was cured and symptoms in all 5 patients resolved after surgery. None of the patients showed symptom recurrence. CONCLUSION: Laparoscopic surgery, for the placement of an extravascular stent and resection of the fibrous ring around the end of the LRV outflow to the inferior vena cava appears feasible and safe and offers an alternative minimally invasive for the management of NCS.


Assuntos
Laparoscopia , Implantação de Prótese/métodos , Síndrome do Quebra-Nozes/cirurgia , Stents , Adulto , Estudos de Viabilidade , Feminino , Humanos , Laparoscopia/efeitos adversos , Masculino , Implantação de Prótese/efeitos adversos , Estudos Retrospectivos , Procedimentos Cirúrgicos Vasculares/métodos
10.
Oncotarget ; 8(16): 27286-27299, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28460483

RESUMO

Epidermal growth factor receptor (EGFR) and insulin-like growth factor 1 receptor (IGF-1R) both overexpressed on non-small cell lung cancer (NSCLC) and are known cooperatively to promote tumor progression and drug resistance. This study was to construct a novel bispecific fusion protein EGF-IGF-LDP-AE consisting of EGFR and IGF-IR specific ligands (EGF and IGF-1) and lidamycin, an enediyne antibiotic with potent antitumor activity, and investigate its antitumor efficacy against NSCLC. Binding and internalization assays showed that EGF-IGF-LDP protein could bind to NSCLC cells with high affinity and then internalized into cells with higher efficiency than that of monospecific proteins. In vitro, the enediyne-energized analogue of bispecific fusion protein (EGF-IGF-LDP-AE) displayed extremely potent cytotoxicity to NSCLC cell lines with IC50<10-11 mol/L. Moreover, the bispecific protein EGF-IGF-LDP-AE was more cytotoxic than monospecific proteins (EGF-LDP-AE and LDP-IGF-AE) and lidamycin. In vivo, EGF-IGF-LDP-AE markedly inhibited the growth of A549 xenografts, and the efficacy was more potent than that of lidamycin and monospecific counterparts. EGF-IGF-LDP-AE caused significant cell cycle arrest and it also induced cell apoptosis in a dosage-dependent manner. Pretreatment with EGF-IGF-LDP-AE inhibited EGF-, IGF-stimulated EGFR and IGF-1R phosphorylation, and blocked two main downstream signaling molecules AKT and ERK activation. These data suggested that EGF-LDP-IGF-AE protein would be a promising targeted agent for NSCLC patients with EGFR and/or IGF-1R overexpression.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Enedi-Inos , Receptores ErbB/antagonistas & inibidores , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Neoplasias Pulmonares/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Enedi-Inos/química , Receptores ErbB/metabolismo , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Camundongos , Ligação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Dis Model Mech ; 9(11): 1357-1366, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27736740

RESUMO

Brandt's voles have an annual cycle of body weight and adiposity. These changes can be induced in the laboratory by manipulation of photoperiod. In the present study, male captive-bred Brandt's voles aged 35 days were acclimated to a short day (SD) photoperiod (8L:16D) for 70 days. A subgroup of individuals (n=16) were implanted with transmitters to monitor physical activity and body temperature. They were then randomly allocated into long day (LD=16L:8D) (n=19, 8 with transmitters) and SD (n=18, 8 with transmitters) groups for an additional 70 days. We monitored aspects of energy balance, glucose and insulin tolerance (GTT and ITT), body composition and organ fat content after exposure to the different photoperiods. LD voles increased in weight for 35 days and then re-established stability at a higher level. At the end of the experiment LD-exposed voles had greater white adipose tissue mass than SD voles (P=0.003). During weight gain they did not differ in their food intake or digestive efficiency; however, daily energy expenditure was significantly reduced in the LD compared with SD animals (ANCOVA, P<0.05) and there was a trend to reduced resting metabolic rate RMR (P=0.075). Physical activity levels were unchanged. Despite different levels of fat storage, the GTT and ITT responses of SD and LD voles were not significantly different, and these traits were not correlated to body fatness. Hence, the photoperiod-induced obesity was independent on disruptions to glucose homeostasis, indicating a potential adaptive decoupling of these states in evolutionary time. Fat content in both the liver and muscle showed no significant difference between LD and SD animals. How voles overcome the common negative aspects of fat storage might make them a useful model for understanding the phenomenon of 'healthy obesity'.


Assuntos
Arvicolinae/fisiologia , Obesidade/patologia , Fotoperíodo , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/patologia , Adiposidade , Animais , Arvicolinae/genética , Composição Corporal , Peso Corporal , Tamanho Celular , Modelos Animais de Doenças , Metabolismo Energético , Regulação da Expressão Gênica , Teste de Tolerância a Glucose , Homeostase , Inflamação/patologia , Insulina/metabolismo , Masculino , Obesidade/genética
12.
Sci Rep ; 6: 31626, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27554919

RESUMO

Previous studies at 21 °C and 5 °C suggest that in Swiss mice sustained energy intake (SusEI) and reproductive performance are constrained by the mammary capacity to produce milk. We aimed to establish if this constraint also applied at higher ambient temperature (30 °C). Female Swiss mice lactating at 30 °C had lower asymptotic food intake and weaned lighter litters than those at 21 °C. Resting metabolic rate, daily energy expenditure, milk energy output and suckling time were all lower at 30 °C. In a second experiment we gave mice at 30 °C either 6 or 9 pups to raise. Female performance was independent of litter size, indicating that it is probably not controlled by pup demands. In a third experiment we exposed only the mother, or only the offspring to the elevated temperature. In this case the performance of the mother was only reduced when she was exposed, and not when her pups were exposed, showing that the high temperature directly constrains female performance. These data suggest that at 30 °C SusEI and reproductive performance are likely constrained by the capacity of females to dissipate body heat, and not indirectly via pup demands. Constraints seem to change with ambient temperature in this strain of mouse.


Assuntos
Ingestão de Energia , Lactação/fisiologia , Termogênese , Animais , Metabolismo Basal , Composição Corporal , Metabolismo Energético , Feminino , Tamanho da Ninhada de Vivíparos , Masculino , Camundongos
13.
Mol Med Rep ; 12(4): 5723-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26252504

RESUMO

Mesenchymal stem cells (MSCs) have become a recent focus of experimental and clinical research regarding myocardial regeneration. However, the therapeutic potential of these cells is limited by poor survival. Prostaglandin E1 (PGE1) is known to have anti­inflammatory and anti­apoptotic effects on the myocardium. The aim of the present study was to determine whether PGE1 could protect MSCs against serum deprivation (SD)­induced apoptosis. An SD model was used to induce apoptosis in MSCs in vitro. Apoptotic morphological changes were detected by Hoechst 33258 fluorescent nuclear staining; and Annexin V­fluorescein isothiocyanate/propidium iodide (PI) double staining and flow cytometry was used to quantify the rate of apoptosis. Western blot analysis was used to detect the expression levels of the apoptosis­associated proteins Bcl­2, Bax and caspase­3. The results of the present study demonstrated that SD induced apoptosis of MSCs, and that treatment with PGE1 attenuated the morphological changes characteristic of apoptosis. Annexin V/PI staining showed that the rate of apoptosis gradually increased with the duration of ischemia. Furthermore, treatment with PGE1 significantly reduced SD­induced apoptosis, decreased the protein expression levels of Bax and caspase­3, and increased the expression levels of Bcl­2. These data suggest that PGE1 is able to influence the survival of MSCs under certain conditions. These results may aid in improving the therapeutic efficacy of MSC transplantation used to treat chronic ischemic heart disease.


Assuntos
Alprostadil/farmacologia , Apoptose/efeitos dos fármacos , Meios de Cultura Livres de Soro/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Animais , Anexina A5/metabolismo , Apoptose/genética , Caspase 3/genética , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro/química , Feminino , Fêmur/citologia , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Expressão Gênica/efeitos dos fármacos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Cultura Primária de Células , Propídio , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Tíbia/citologia , Tíbia/efeitos dos fármacos , Tíbia/metabolismo
14.
Asian Pac J Cancer Prev ; 14(10): 6069-75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24289627

RESUMO

BACKGROUND: At present, the diagnosis of colorectal cancer (CRC) requires a colorectal biopsy which is an invasive procedure. We undertook this pilot study to develop an alternative method and potential new biomarkers for diagnosis, and validated a set of well-integrated tools called ClinProt to investigate the serum peptidome in CRC patients. METHODS: Fasting blood samples from 67 patients diagnosed with CRC by histological diagnosis, 55 patients diagnosed with colorectal adenoma by biopsy, and 65 healthy volunteers were collected. Division was into a model construction group and an external validation group randomly. The present work focused on serum proteomic analysis of model construction group by ClinProt Kit combined with mass spectrometry. This approach allowed construction of a peptide pattern able to differentiate the studied populations. An external validation group was used to verify the diagnostic capability of the peptidome pattern blindly. An immunoassay method was used to determine serum CEA of CRC and controls. RESULTS: The results showed 59 differential peptide peaks in CRC, colorectal adenoma and health volunteers. A genetic algorithm was used to set up the classification models. Four of the identified peaks at m/z 797, 810, 4078 and 5343 were used to construct peptidome patterns, achieving an accuracy of 100% (> CEA, P < 0. 05). Furthermore, the peptidome patterns could differentiate the validation group with high accuracy close to 100%. CONCLUSIONS: Our results showed that proteomic analysis of serum with MALDI-TOF MS is a fast and reproducible approach, which may provide a novel approach to screening for CRC.


Assuntos
Adenoma/sangue , Biomarcadores Tumorais/sangue , Proteínas Sanguíneas/análise , Neoplasias Colorretais/sangue , Separação Imunomagnética/métodos , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Adenoma/patologia , Estudos de Casos e Controles , Colo/metabolismo , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fragmentos de Peptídeos/análise , Mapeamento de Peptídeos , Prognóstico , Reto/metabolismo
15.
J Exp Biol ; 216(Pt 22): 4242-50, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23997195

RESUMO

Life history parameters appear to be traded off against each other, but the physiological mechanisms involved remain unclear. One hypothesis is that potentially energetically costly processes such as immune function and protection from oxidative stress may be compromised during reproductive attempts because of selective resource allocation. Lower temperatures also impose energy costs, and hence allocation decisions might be more pronounced when animals are forced to reproduce in the cold. Here, we experimentally tested whether reproduction at different ambient temperatures was associated with elevated oxidative stress and suppressed immune function in Mongolian gerbils (Meriones unguiculatus). Using a variety of different markers for both immune function and oxidative stress, we found that some measures of immune function (serum bactericidal capacity and size of the thymus) were significantly suppressed, while some measures of oxidative protection [serum superoxide dismutase (SOD) activity and glutathione peroxidase (GPx) activity] were also reduced, and a marker of oxidative damage (protein carbonyls in serum) was increased in lactating compared with non-reproductive gerbils. These changes were in line with the selective resource allocation predictions. However, the phytohaemagglutinin response and serum total immunoglobulin (IgG) were not suppressed, and other markers of oxidative damage [malondialdehyde (MDA) (TBARS) and protein carbonyls in the liver] were actually lower in lactating compared with non-reproductive gerbils, consistent with increased levels of SOD activity and total antioxidant capacity in the liver. These latter changes were opposite of the expectations based on resource allocation. Furthermore, other measures of protection (GPx levels in the liver and protein thiols in both serum and liver) and damage [MDA (TBARS) in serum] were unrelated to reproductive status. Ambient temperature differences did not impact on these patterns. Collectively, our results indicated that the inferred effects of reproduction on immunosuppression and oxidative damage, and hence support or otherwise for particular physiological mechanisms that underpin life history trade-offs, are critically dependent on the exact markers and tissues used. This may be because during reproduction individuals selectively allocate protection to some key tissues, but sacrifice protection of others.


Assuntos
Tolerância Imunológica/fisiologia , Estresse Oxidativo/fisiologia , Reprodução/fisiologia , Temperatura , Análise de Variância , Animais , Feminino , Gerbillinae , Glutationa Peroxidase/sangue , Tamanho do Órgão/fisiologia , Fito-Hemaglutininas/metabolismo , Reprodução/imunologia , Teste Bactericida do Soro , Estatísticas não Paramétricas , Superóxido Dismutase/sangue , Substâncias Reativas com Ácido Tiobarbitúrico , Timo/fisiologia
16.
J Exp Biol ; 216(Pt 17): 3358-68, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23737554

RESUMO

We evaluated factors limiting lactating Mongolian gerbils (Meriones unguiculatus) at three temperatures (10, 21 and 30°C). Energy intake and daily energy expenditure (DEE) increased with decreased ambient temperature. At peak lactation (day 14 of lactation), energy intake increased from 148.7±5.7 kJ day(-1) at 30°C to 213.1±8.2 kJ day(-1) at 21°C and 248.7±12.3 kJ day(-1) at 10°C. DEE increased from 105.1±4.0 kJ day(-1) at 30°C to 134.7±5.6 kJ day(-1) at 21°C and 179.5±8.4 kJ day(-1) at 10°C on days 14-16 of lactation. With nearly identical mean litter sizes, lactating gerbils at 30°C exported 32.0 kJ day(-1) less energy as milk at peak lactation than those allocated to 10 or 21°C, with no difference between the latter groups. On day 14 of lactation, the litter masses at 10 and 30°C were 12.2 and 9.3 g lower than those at 21°C, respectively. Lactating gerbils had higher thermal conductance of the fur and lower UCP-1 levels in brown adipose tissue than non-reproductive gerbils, independent of ambient temperature, suggesting that they were attempting to avoid heat stress. Thermal conductance of the fur was positively related to circulating prolactin levels. We implanted non-reproductive gerbils with mini-osmotic pumps that delivered either prolactin or saline. Prolactin did not influence thermal conductance of the fur, but did reduce physical activity and UCP-1 levels in brown adipose tissue. Transferring lactating gerbils from warm to hot conditions resulted in reduced milk production, consistent with the heat dissipation limit theory, but transferring them from warm to cold conditions did not elevate milk production, consistent with the peripheral limitation hypothesis, and placed constraints on pup growth.


Assuntos
Regulação da Temperatura Corporal , Ingestão de Alimentos , Ingestão de Energia , Gerbillinae/fisiologia , Lactação , Animais , Feminino , Temperatura
17.
Gene ; 525(1): 35-40, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23651591

RESUMO

OBJECTIVE: The aim of this meta-analysis is to evaluate the associations between functional polymorphisms in the interleukin-4 (IL4) gene and individuals' responses to hepatitis B vaccine and their susceptibility to hepatitis B virus (HBV) infection. METHODS: A literature search on articles published before December 1st, 2012 was conducted in PubMed, Embase, Web of Science and China BioMedicine (CBM) databases. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Statistical analyses were performed using the STATA 12.0 software. RESULTS: Eight studies were eligible for inclusion in this meta-analysis, including five cross-sectional studies on individual's response to hepatitis B vaccine and three case-control studies on HBV infection risk. The meta-analysis results showed that the T allele of rs2243250, the T allele of rs2070874, and the C allele of rs2227284 in IL4 gene were associated with high responses to hepatitis B vaccine. Further subgroup analysis by ethnicity showed that there was a significant association between IL4 genetic polymorphisms and an individual's responses to hepatitis B vaccine among Asian populations, but similar association was not found among Caucasian populations. However, there was no evidence indicating a correlation between IL4 genetic polymorphism and susceptibility to HBV infection. CONCLUSION: Our current meta-analysis suggests that rs2243250, rs2070874 and rs2227284 polymorphisms in IL4 gene may play an important role in determining the response to hepatitis B vaccine, especially among Asian populations. However, further studies are still needed to evaluate the associations between IL4 genetic polymorphisms and HBV infection risk.


Assuntos
Vacinas contra Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B/genética , Interleucina-4/genética , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , Estudos Transversais , Predisposição Genética para Doença , Humanos , Polimorfismo Genético
18.
Huan Jing Ke Xue ; 34(1): 98-107, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23487924

RESUMO

Sediment quality criterion (SQC) is the concentrations of sediment-associated contaminants that are unlikely to be associated with sediment toxicity or other adverse effects on benthic invertebrates. Thus, the derivation of SQC is crucial to protect benthic invertebrates, and can serve as the tool for scientific sediment management. Sediment, interstitial water, and plant samples were collected at 43 sampling sites from the Xiangjiang River, and metal concentrations were determined. Based on equilibrium partitioning approach, spiked sediment toxicity approach using Hyalella azteca, and background value approach, SQC for Cd and Hg in the Xiangjiang River was derived. Results showed that, SQC-L for Cd and Hg in the Xiangjiang River were 1.89 mg x kg(-1) and 0.13 mg x kg(-1) respectively, and SQC-H were 28.32 mg x kg(-1) and 0.79 mg x kg(-1) respectively. SQC were comparable to those in previous studies. Also, the reasonability of SQC was demonstrated by the heavy metal concentrations in plants, matching sediment chemistry and toxicity data for benthic invertebrates in the Xiangjiang River. To assess the sediment quality of Xiangjiang, metal concentrations in sediment samples were compared with the SQC. It was found that the proportion of sampling sites with Cd and Hg concentrations lower than SQC-L or higher than SQC-H was low, and 74.4% and 76.7% of sampling sites showed Cd and Hg concentrations between SQC-L and SQC-H.


Assuntos
Cádmio/análise , Sedimentos Geológicos/química , Mercúrio/análise , Rios/química , Poluentes Químicos da Água/análise , Animais , Cádmio/toxicidade , China , Monitoramento Ambiental/métodos , Invertebrados/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
19.
Cochrane Database Syst Rev ; (2): CD004434, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23450552

RESUMO

BACKGROUND: Pulmonary arterial hypertension is a devastating disease, which leads to right heart failure and premature death. Recent evidence suggests that endothelin receptor antagonists may be promising drugs in the treatment of pulmonary arterial hypertension. OBJECTIVES: To evaluate the efficacy of endothelin receptor antagonists in pulmonary arterial hypertension. SEARCH METHODS: We searched CENTRAL (Cochrane Central Register of Controlled Trials), MEDLINE, EMBASE, and the reference section of retrieved articles. Searches are current as of January 2012. SELECTION CRITERIA: We included randomised trials (RCTs) and quasi-randomised trials involving patients with pulmonary arterial hypertension. DATA COLLECTION AND ANALYSIS: Five review authors independently selected studies, assessed study quality and extracted data. MAIN RESULTS: We included 12 randomised controlled trials involving 1471 patients. All the trials were of relatively short duration (12 weeks to six months). After treatment, patients treated with endothelin receptor antagonists could walk on average 33.71 metres (95% confidence interval (CI) 24.90 to 42.52 metres) further than those treated with placebo in a six-minute walk test. Endothelin receptor antagonists improved more patients' World Health Organization/New York Heart Association (WHO/NYHA) functional class status than placebo (odds ratio (OR) 1.60; 95% CI 1.20 to 2.14), and reduced the odds of functional class deterioration compared with placebo (OR 0.26; 95% CI 0.16 to 0.42). There was a reduction in mortality that did not reach statistical significance on endothelin receptor antagonists (OR 0.57; 95% CI 0.26 to 1.24), and limited data suggest that endothelin receptor antagonists improve the Borg dyspnoea score and cardiopulmonary haemodynamics in symptomatic patients. Hepatic toxicity was not common, and endothelin receptor antagonists were well tolerated in this population. However, several cases of irreversible liver failure caused by sitaxsentan have been reported that led to license holder for sitaxsentan to withdraw the product from all markets worldwide. AUTHORS' CONCLUSIONS: Endothelin receptor antagonists can increase exercise capacity, improve WHO/NYHA functional class, prevent WHO/NYHA functional class deterioration, reduce dyspnoea and improve cardiopulmonary haemodynamic variables in patients with pulmonary arterial hypertension with WHO/NYHA functional class II and III. However, there was only a trend towards endothelin receptor antagonists reducing mortality in patients with pulmonary arterial hypertension. Efficacy data are strongest in those with idiopathic pulmonary hypertension. The irreversible liver failure caused by sitaxsentan and its withdrawal from global markets emphasise the importance of hepatic monitoring in patients treated with endothelin receptor antagonists.


Assuntos
Anti-Hipertensivos/uso terapêutico , Antagonistas dos Receptores de Endotelina , Hipertensão Pulmonar/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
World J Gastroenterol ; 18(44): 6504-9, 2012 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-23197899

RESUMO

Progressive familial intrahepatic cholestasis type 1 is a rare disease that is characterized by low serum γ-glutamyltransferase levels due to mutation in ATP8B1. We present a 23-year-old male who experienced persistent marked pruritus for eighteen years and recurrent jaundice for thirteen years, in addition to cholestasis that eventually became fatal. Genetic sequencing studies of the entire coding (exon) sequences of ATP8B1 and ABCB11 uncovered a novel heterozygous missense 3035G>T mutation (S1012I) and a synonymous 696T>C mutation in ATP8B1. The patient's progression was associated with not only impaired familial intrahepatic cholestasis 1 (FIC1) function but also impaired bile salt export pump expression due to the impaired FIC1 function. Our findings show that patients with intermittent cholestasis can develop progressive liver disease even after several decades and require regular follow up.


Assuntos
Adenosina Trifosfatases/genética , Colestase Intra-Hepática/genética , Mutação de Sentido Incorreto , Adenosina Trifosfatases/metabolismo , Biópsia , Colagogos e Coleréticos/uso terapêutico , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/tratamento farmacológico , Colestase Intra-Hepática/metabolismo , Análise Mutacional de DNA , Evolução Fatal , Predisposição Genética para Doença , Humanos , Imageamento por Ressonância Magnética , Masculino , Fenótipo , Resultado do Tratamento , Ácido Ursodesoxicólico/uso terapêutico , Vitaminas/uso terapêutico , Adulto Jovem
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