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1.
Braz J Anesthesiol ; 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37453497

RESUMO

BACKGROUND: Acute Kidney Injury (AKI) is a common complication after cardiac surgery and has been associated with poor outcomes. Dexmedetomidine (DEX) has been shown to confer direct renoprotection based on some animal and clinical studies, but data from other trials came to the opposite conclusion following cardiac surgery. This meta-analysis was conducted to evaluate the effects of perioperative DEX administration on the occurrence of AKI and the outcomes after cardiac surgery. METHODS: We searched databases including EMBASE, PubMed, and Cochrane CENTRAL for Randomized Controlled Trials (RCTs) focused on DEX for AKI in adult patients after cardiac surgery. The primary outcome was incidence of AKI. Secondary outcomes were Mechanical Ventilation (MV) duration, Intensive Care Unit (ICU) Length Of Stay (LOS), hospital LOS and mortality. RESULTS: Fifteen trials enrolling 2907 study patients were collected in the meta-analyses. Compared with controls, DEX reduced the incidence of postoperative AKI (Odds Ratio [OR = 0.66]; 95% Confidence Interval [95% CI 0.48-0.91]; p = 0.01), and there was no significant difference between groups in postoperative mortality (OR = 0.63; 95% CI 0.32-1.26; p = 0.19), MV duration (Weighted Mean Difference [WMD = -0.44]; 95% CI -1.50-0.63; p = 0.42), ICU LOS (WMD = -1.19; 95% CI -2.89-0.51; p = 0.17), and hospital LOS (WMD = -0.31; 95% CI -0.76-0.15; p = 0.19). CONCLUSIONS: Perioperative DEX reduced the incidence of postoperative AKI in adult patients undergoing cardiac surgery. No significant decrease existed in mortality, MV duration, ICU LOS and hospital LOS owing to DEX administration.

2.
Med Image Anal ; 88: 102833, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37267773

RESUMO

In-utero fetal MRI is emerging as an important tool in the diagnosis and analysis of the developing human brain. Automatic segmentation of the developing fetal brain is a vital step in the quantitative analysis of prenatal neurodevelopment both in the research and clinical context. However, manual segmentation of cerebral structures is time-consuming and prone to error and inter-observer variability. Therefore, we organized the Fetal Tissue Annotation (FeTA) Challenge in 2021 in order to encourage the development of automatic segmentation algorithms on an international level. The challenge utilized FeTA Dataset, an open dataset of fetal brain MRI reconstructions segmented into seven different tissues (external cerebrospinal fluid, gray matter, white matter, ventricles, cerebellum, brainstem, deep gray matter). 20 international teams participated in this challenge, submitting a total of 21 algorithms for evaluation. In this paper, we provide a detailed analysis of the results from both a technical and clinical perspective. All participants relied on deep learning methods, mainly U-Nets, with some variability present in the network architecture, optimization, and image pre- and post-processing. The majority of teams used existing medical imaging deep learning frameworks. The main differences between the submissions were the fine tuning done during training, and the specific pre- and post-processing steps performed. The challenge results showed that almost all submissions performed similarly. Four of the top five teams used ensemble learning methods. However, one team's algorithm performed significantly superior to the other submissions, and consisted of an asymmetrical U-Net network architecture. This paper provides a first of its kind benchmark for future automatic multi-tissue segmentation algorithms for the developing human brain in utero.


Assuntos
Processamento de Imagem Assistida por Computador , Substância Branca , Gravidez , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Cabeça , Feto/diagnóstico por imagem , Algoritmos , Imageamento por Ressonância Magnética/métodos
3.
Health Inf Sci Syst ; 11(1): 17, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36998806

RESUMO

The magnetic resonance (MR) images of fetuses make it possible for doctors to detect out pathological fetal brains in early stages. Brain tissue segmentation is prerequisite for making brain morphology and volume analyses. nnU-Net is an automatic segmentation method based on deep learning. It can adaptively configure itself, so as to adapt to a specific task via preprocessing, network architecture, training, and post-processing. Therefore, we adapt nnU-Net to segment seven types of fetal brain tissues, including external cerebrospinal fluid, gray matter, white matter, ventricle, cerebellum, deep gray matter, and brainstem. With regard to the characteristics of the FeTA 2021 data, some adjustments are made to the original nnU-Net, so that it can segment seven types of fetal brain tissues precisely as far as possible. The average segmentation results on FeTA 2021 training data demonstrate that our advanced nnU-Net is superior to the peers including SegNet, CoTr, AC U-Net and ResUnet. Its average segmentation results are 0.842, 11.759 and 0.957 in terms of Dice, HD95 and VS criteria. Moreover, the experimental results on FeTA 2021 test data further demonstrate that our advanced nnU-Net has obtained good segmentation performance of 0.774, 14.699 and 0.875 in terms of Dice, HD95 and VS, ranked the third in FeTA 2021 challenge. Our advanced nnU-Net realized the task for segmenting the fetal brain tissues using MR images of different gestational ages, which can help doctors to make correct and seasonable diagnoses.

4.
Sci Total Environ ; 846: 157484, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35868402

RESUMO

Irrigation has been considered an effective approach for decreasing cadmium (Cd) uptake and accumulation in rice (Oryza sativa), but increasing evidence shows that the effects of different water management strategies on Cd accumulation in rice are contradictory in different studies, and the detailed regulatory mechanisms remain unconfirmed. Most previous studies have shown that irrigation regulates Cd accumulation in rice mainly by affecting Cd bioavailability, pH and redox potential (Eh) in soil, and few reports have focused on the function of oxygen (O2) in regulating the physiological mechanisms of rice on Cd tolerance or accumulation. Here, we concluded that irrigation affects Cd bioavailability, pH and Eh in soil mainly by regulating O2 content. In addition, recent studies have also shown that irrigation-regulated O2 also affects Cd accumulation in rice by affecting iron plaque (IP), the radial oxygen loss (ROL) barrier, the cell wall and mass flow in rice roots. All these results indicate that O2 is the key factor in irrigation-regulated Cd accumulation in rice, and dramatic result variations from different irrigation experiments are due to the different rhizosphere O2 conditions. This review will help clarify the effects and regulatory mechanisms of irrigation on Cd accumulation in rice and reveal the roles of O2 in this process.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Oryza/química , Oxigênio , Solo/química , Poluentes do Solo/análise , Água , Abastecimento de Água
5.
Int J Mol Sci ; 23(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35008962

RESUMO

MicroRNA408 (miR408) is an ancient and highly conserved miRNA, which is involved in the regulation of plant growth, development and stress response. However, previous research results on the evolution and functional roles of miR408 and its targets are relatively scattered, and there is a lack of a systematic comparison and comprehensive summary of the detailed evolutionary pathways and regulatory mechanisms of miR408 and its targets in plants. Here, we analyzed the evolutionary pathway of miR408 in plants, and summarized the functions of miR408 and its targets in regulating plant growth and development and plant responses to various abiotic and biotic stresses. The evolutionary analysis shows that miR408 is an ancient and highly conserved microRNA, which is widely distributed in different plants. miR408 regulates the growth and development of different plants by down-regulating its targets, encoding blue copper (Cu) proteins, and by transporting Cu to plastocyanin (PC), which affects photosynthesis and ultimately promotes grain yield. In addition, miR408 improves tolerance to stress by down-regulating target genes and enhancing cellular antioxidants, thereby increasing the antioxidant capacity of plants. This review expands and promotes an in-depth understanding of the evolutionary and regulatory roles of miR408 and its targets in plants.


Assuntos
Evolução Biológica , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , RNA Mensageiro/genética , RNA de Plantas , Família Multigênica , Especificidade de Órgãos , Desenvolvimento Vegetal , Fenômenos Fisiológicos Vegetais , Estresse Fisiológico
6.
Emerg Themes Epidemiol ; 11: 17, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25352909

RESUMO

BACKGROUND: In the literature, different shapes of associations have been found between body mass index (BMI) and mortality and some of the findings were opposite to each other. The association of BMI and mortality in a single cohort has been found to be dynamic that can lead to different findings under different settings. The identified dynamic features were consistent with the heterogeneity in the literature. It is meaningful to find out whether such dynamic associations exist in other populations. METHODS: Data of six different cohorts were used for analysis and comparison. The proportional hazards assumptions for BMI in Cox models were tested to identify dynamic associations in each cohort. Time-dependent covariates Cox model was used to model the association of BMI and mortality risk as functions of follow-up time. The Cox model was applied to the pooled data with survival times censored at 5 to 40 years to show the potential impact of the dynamic association on traditional Meta-analysis. RESULTS AND DISCUSSION: Dynamic associations were identified in six models (4 for men and 2 for women), four of which showed the same changing pattern: the elevated mortality risk for low BMI decreased while that for high BMI increased with follow-up time. When the Cox model was applied to the pooled data excluding the largest and also the shortest cohort, low BMI was but high BMI was not associated with high mortality for men with censoring at 5 years but the association for low BMI became weaker and that for high BMI became much stronger when censoring time was at 40 years. The dynamic association indicated that shorter studies tend to obtain inverse associations between BMI and mortality while longer studies tend to obtain J-shaped associations. CONCLUSIONS: Different or even opposite results about body weight and mortality in the literature may be in part due to the underlying dynamic association of BMI and mortality. The dynamic features need to be taken into consideration in future studies.

7.
World J Gastroenterol ; 10(22): 3269-73, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15484298

RESUMO

AIM: To evaluate the efficacy and safety of oxymatrine capsule in treatment of hepatic fibrosis in patients with chronic viral hepatitis. METHODS: It was a randomized, double blind, placebo-controlled, multicenter clinical study. One hundred and forty-four patients were divided into oxymatrine capsule group(group A) and placebo group (group B). The course was 52 wk. Patients were visited once every 12 wk and the last visit was at 12 wk after cessation of the treatment. All patients had liver biopsy before treatment. part of them had a second biopsy at the end of therapy. Clinical symptoms, liver function test, serum markers of hepatic fibrosis were tested. Ultrasound evaluation was performed before, during and at the end of therapy. RESULTS: One hundred and forty-four patients enrolled in the study. Of them 132 patients completed the study according to the protocol,49 patients had liver biopsy twice (25 patients in group A and 24 in group B). At the end of therapy, significant improvements in hepatic fibrosis and inflammatory activity based on Semi-quantitative scoring system (SSS) were achieved in group A. The total effective rate of the treatment was 48.00%, much higher than that of 4.17% in group B (P<0.05). Significant improvement in serum markers of hepatic fibrosis such as hyaluronic acid (HA) and type III procollagenic peptide (P III P) in group A was seen (P<0.05). The total effective rate of serum markers at the end of therapy in group A was 68.19%, much higher than that of 34.85% in group B (P<0.05). The total effective rate of noninvasive markers at the end of therapy in group A was 66.67%, much higher than that of 30.30% in group B (P<0.05). The rate of adverse events was similar in two groups. CONCLUSION: Oxymatrine capsule is effective and safe in treatment of hepatic fibrosis due to chronic viral hepatitis.


Assuntos
Alcaloides/administração & dosagem , Antivirais/administração & dosagem , Hepatite Viral Humana/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Idoso , Alcaloides/efeitos adversos , Antivirais/efeitos adversos , Biomarcadores , Cápsulas , Doença Crônica , Método Duplo-Cego , Feminino , Hepatite Viral Humana/patologia , Humanos , Fígado/patologia , Fígado/fisiologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Placebos , Quinolizinas , Resultado do Tratamento
8.
World J Gastroenterol ; 9(11): 2480-3, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14606080

RESUMO

AIM: To evaluate the efficacy and safety of capsule oxymatrine in the treatment of chronic hepatitis B. METHODS: A randomised double-blind and placebo-controlled multicenter trial was conducted. Injection of oxymatrine was used as positive-control drug. A total of 216 patients with chronic hepatitis B entered the study for 24 weeks, of them 108 received capsule oxymatrine, 36 received injection of oxymatrine, and 72 received placebo. After and before the treatment, clinical symptoms, liver function, serum hepatitis B virus markers, and adverse drug reaction were observed. RESULTS: Among the 216 patients, six were dropped off, and 11 inconsistent with the standard were excluded. Therefore, the efficacy and safety of oxymatrine in patients were analysed. In the capsule treated patients, 76.47% became normal in ALT level, 38.61% and 31.91% became negative both in HBV DNA and in HBeAg. In the injection treated patients, 83.33% became normal in ALT level, 43.33% and 39.29% became negative both in HBV DNA and in HBeAg. In the placebo treated patients, 40.00% became normal in ALT level, 7.46% and 6.45% became negative both in HBV DNA and in HBeAg. The rates of complete response and partial response were 24.51% and 57.84% in the capsule treated patients, and 33.33% and 50.00% in the injection treated patients, and 2.99% and 41.79% in the placebo treated patients, respectively. There was no significance between the two groups of patients, but both were significantly higher than the placebo. The adverse drug reaction rates of the capsule, injection and placebo were 7.77%, 6.67% and 8.82%, respectively. There was no statistically significant difference among them. CONCLUSION: Oxymatrine is an effective and safe agent for the treatment of chronic hepatitis B.


Assuntos
Alcaloides/administração & dosagem , Antivirais/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Administração Oral , Alanina Transaminase/sangue , Alcaloides/efeitos adversos , Antivirais/efeitos adversos , Método Duplo-Cego , Antígenos de Superfície da Hepatite B/sangue , Humanos , Injeções Intramusculares , Placebos , Quinolizinas , Resultado do Tratamento
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