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1.
Sensors (Basel) ; 24(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38339752

RESUMO

High-accuracy heading angle is significant for estimating autonomous vehicle attitude. By integrating GNSS (Global Navigation Satellite System) dual antennas, INS (Inertial Navigation System), and a barometer, a GNSS/INS/Barometer fusion method is proposed to improve vehicle heading angle accuracy. An adaptive Kalman filter (AKF) is designed to fuse the INS error and the GNSS measurement. A random sample consensus (RANSAC) method is proposed to improve the initial heading angle accuracy applied to the INS update. The GNSS heading angle obtained by a dual-antenna orientation algorithm is additionally augmented to the measurement variable. Furthermore, the kinematic constraint of zero velocity in the lateral and vertical directions of vehicle movement is used to enhance the accuracy of the measurement model. The heading errors in the open and occluded environment are 0.5418° (RMS) and 0.636° (RMS), which represent reductions of 37.62% and 47.37% compared to the extended Kalman filter (EKF) method, respectively. The experimental results demonstrate that the proposed method effectively improves the vehicle heading angle accuracy.

2.
J Intern Med ; 293(2): 212-227, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36208172

RESUMO

BACKGROUND AND AIMS: The role of thrombolytic therapy in patients with portal venous system thrombosis (PVST) remains ambiguous. This study aimed to systematically collect available evidence and evaluate the efficacy and safety of thrombolysis for PVST. METHODS: Eligible studies were searched via PubMed, EMBASE, and Cochrane Library databases. Among the cohort studies, meta-analyses were performed to assess the outcomes of PVST patients receiving thrombolysis. Pooled proportions were calculated. Among the case reports and case series, logistic regression analyses were performed to identify the risk factors for outcomes of PVST patients receiving thrombolysis. Odds ratios (ORs) were calculated. RESULTS: Among the 2134 papers initially identified, 29 cohort studies and 131 case reports or case series were included. Based on the cohort studies, the pooled rates of overall response to thrombolytic therapy, complete recanalization of PVST, bleeding events during thrombolysis, further bowel resection, thrombosis recurrence, and 30-day mortality were 93%, 58%, 18%, 3%, 1%, and 4%, respectively. Based on the case reports and case series, acute pancreatitis (OR = 0.084), history of liver transplantation (OR = 13.346), and interval between onset of symptoms and initiation of thrombolysis ≤14 days (OR = 3.105) were significantly associated with complete recanalization of PVST; acute pancreatitis (OR = 6.556) was significantly associated with further bowel resection; but no factors associated with the overall response to thrombolytic therapy, bleeding events during thrombolysis, thrombosis recurrence, and 30-day mortality were identified or could be calculated. CONCLUSION: Early initiation of thrombolysis should be effective for the treatment of PVST. But its benefits for PVST secondary to acute pancreatitis are weakened.


Assuntos
Pancreatite , Trombose , Trombose Venosa , Humanos , Veia Porta/patologia , Trombose Venosa/tratamento farmacológico , Trombose Venosa/etiologia , Doença Aguda , Cirrose Hepática , Trombose/complicações , Hemorragia , Terapia Trombolítica/efeitos adversos , Resultado do Tratamento
3.
Thromb J ; 20(1): 63, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224604

RESUMO

Neutrophil extracellular traps (NETs) may be associated with the development of thrombosis. Experimental studies have confirmed the presence of NETs in thrombi specimens and potential role of NETs in the mechanisms of thrombosis. Clinical studies also have demonstrated significant changes in the levels of serum or plasma NETs biomarkers, such as citrullinated histones, myeloperoxidase, neutrophil elastase, nucleosomes, DNA, and their complexes in patients with thrombosis. This paper aims to comprehensively review the currently available evidence regarding the change in the levels of NETs biomarkers in patients with thrombosis, summarize the role of NETs and its biomarkers in the development and prognostic assessment of venous thromboembolism, coronary artery diseases, ischemic stroke, cancer-associated thromboembolism, and coronavirus disease 2019-associated thromboembolism, explore the potential therapeutic implications of NETs, and further discuss the shortcomings of existing NETs biomarkers in serum and plasma and their detection methods.

4.
Andrologia ; 54(3): e14350, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34904262

RESUMO

Activating transcription factor 6 (ATF6), also known as ACHM7, ATF6A, encodes a transcription factor that activates target genes for the unfolded protein response (UPR) during endoplasmic reticulum (ER) stress. It functions as nuclear transcription factor via a cis-acting ER stress response element (ERSE) that is presented in the promoters of genes encoding ER chaperones. Studies have shown that endoplasmic reticulum stress (ERS) can cause damage to spermatozoa and testes, leading to male sterility. And we find that the expression of ATF6 in spermatozoa of some infertile patients is significantly reduced. Then, we construct the Atf6 knockout mice model and interestingly find a decline in male fertility. The downstream gene testis-specific serine/threonine-protein kinase 4 (Tssk4) is screened based on transcriptome sequencing. We use Western blot and real-time PCR to confirm this result in both 293T cells and Atf6 knockout mice. TSSK4 is essential in male germ cell genesis and sperm maturation. Our results suggest that the expression of TSSK4 may be regulated by ATF6. The effect of Atf6 knockout on the reproductive development of male mice may be related to the low expression of TSSK4, which further verify that there may be some relationship between ERS and male reproduction.


Assuntos
Fator 6 Ativador da Transcrição , Retículo Endoplasmático , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Animais , Retículo Endoplasmático/metabolismo , Humanos , Masculino , Camundongos , Camundongos Knockout , Espermatogênese/genética , Fatores de Transcrição/genética
5.
J Transl Med ; 19(1): 295, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34238315

RESUMO

BACKGROUND: Metastasis and invasion are crucial in determining the mortality of cervical carcinoma (CC) patients. The epithelial-mesenchymal transition (EMT) is now a universal explanation for the mechanisms of tumor metastasis. Α-chimeric protein (α-chimaerin, CHN1) plays an important role in the regulation of signal transduction and development. However, the molecular regulatory relationships between CHN1 and CC progression in relation to EMT have not yet been identified. METHODS: The expression of CHN1 in CC tissues, adjacent tissues, and lymph node metastases from CC patients was detected by immunohistochemistry. Upregulation and knockdown of CHN1 were achieved by transfection of CC cells. The effect of CHN1 on cell proliferation was determined by CCK-8 and plate clone formation assays. Changes in migration and invasion capabilities were evaluated using scratch migration and transwell invasion assays. The effect of CHN1 overexpression and interference on xenograft tumor growth was determined by tumor weight and pathological analyses. The expression of EMT-related mRNAs was measured by qRT-PCR in transfected CC cells. EMT-related proteins and Akt/GSK-3ß/Snail signaling pathway-related proteins were also evaluated by western blotting. RESULTS: CHN1 was overexpressed in CC tissues and was associated with lymph node metastasis and low survival in CC patients. Overexpression of CHN1 promoted cell proliferation, migration, and invasion in CC cells. In contrast, silencing of CHN1 inhibited these phenomena. Overexpression of CHN1 promoted tumor formation in an in vivo xenograft tumor mouse model, with increased tumor volumes and weights. In addition, CHN1 induced the expression of EMT-related transcription factors, accompanied by the decreased expression of epithelial markers and increased expression of mesenchymal markers. The Akt/GSK-3ß/Snail signaling pathway was activated by overexpression of CHN1 in vitro, and activation of this pathway was inhibited by the signaling pathway inhibitor LY294002. CONCLUSION: These results suggest that CHN1 promotes the development and progression of cervical carcinoma via the Akt/GSK-3ß/Snail pathway by inducing EMT.


Assuntos
Carcinoma , Transição Epitelial-Mesenquimal , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quimerina 1 , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo
6.
BMC Gastroenterol ; 21(1): 253, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34098892

RESUMO

BACKGROUND AND AIM: Hemostasis profile is often complicated in liver cirrhosis. Thromboelastography is a global viscoelastic test recommended by the current practice guideline and consensus. This cross-sectional study aimed to evaluate the association of thromboelastography profile with severity of liver cirrhosis and presence of portal venous system thrombosis (PVST). METHODS: Overall, 116 and 50 cirrhotic patients were included in the Shenyang and Xi'an cohorts, respectively. Thromboelastography parameters were compared between cirrhotic patients with Child-Pugh class A and B/C, those with and without decompensated events, and those with and without PVST. Hypercoagulability would be considered if at least two of the following thromboelastography parameters were met: shortened reactive time (R), shortened coagulation time (K), increased angle, and increased maximum amplitude (MA). RESULTS: In the Shenyang cohort, 16 patients had shortened R, of whom seven (43.75%) had prolonged K and 11 (68.75%) decreased MA. In the Xi'an cohort, 24 patients had shortened R, of whom seven (29.17%) had prolonged K and 15 (62.50%) decreased MA. In the Shenyang cohort, the prevalence of hypercoagulability was not significantly different between cirrhotic patients with Child-Pugh class A and B/C (3.85% vs. 6.25%, P = 0.873), those with and without decompensated events (5.49% vs. 4.00%, P = 1.000), and those with and without PVST (4.17% vs. 5.88%, P = 1.000), which were similar to the results obtained in the Xi'an cohort. CONCLUSION: There is a high rate of discordance between R and other thromboelastography parameters. In addition, hypercoagulability may not be related to more advanced stage of liver cirrhosis or presence of PVST.


Assuntos
Trombose , Trombose Venosa , Estudos Transversais , Humanos , Cirrose Hepática/complicações , Tromboelastografia , Trombose/epidemiologia , Trombose Venosa/complicações , Trombose Venosa/epidemiologia
7.
Environ Sci Technol ; 55(17): 11511-11520, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34374533

RESUMO

Household consumption carbon footprint and inequality reductions are vital for a sustainable society, especially for rural areas. This study, focusing on rural China, one of the fastest growing economies with a massive population, explored the carbon footprint and inequality of household consumption using the latest micro household survey data of 2018 linked to environmental extended input--output analysis. The results show that in 2018 in rural China, the average household carbon footprint is 2.46 tons CO2-eq per capita, which is around one-third of China's average footprint, indicating the large potential for further growth. Housing (45.32%), transportation (20.45%), and food (19.62%) are the dominant contributors to the carbon footprint. Meanwhile, great inequality, with a Gini coefficient of 0.488, among rural households is observed, which is largely due to differences in type of house built or purchased (explaining 24.44% of the variation), heating (18.10%), car purchase (12.44%), and petrol consumption (12.44%). Provinces, average education, and nonfarm income are among the important factors influencing the inequality. In the process of urbanization and rural revitalization, there is a high possibility that the household carbon footprint continues to increase, maintaining high levels of inequality. The current energy transition toward less carbon-intensive fuels in rural China is likely to dampen the growth rates of carbon footprints and potentially decrease inequality. Carbon intensity decrease could significantly reduce carbon footprints, but increase inequality. More comprehensive measures to reduce carbon footprint and inequality are needed, including transitioning to clean energy, poverty alleviation, reduction of income inequality, and better health care coverage.


Assuntos
Pegada de Carbono , Urbanização , China , Características da Família , Humanos , Renda , População Rural
8.
J Gastroenterol Hepatol ; 36(6): 1694-1702, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33393106

RESUMO

BACKGROUND AND AIM: Spontaneous splenorenal shunt (SSRS) is one of the manifestations of portal hypertension in liver cirrhosis. However, the impact of SSRS on long-term survival of cirrhotic patients remains unclear. We hypothesize that SSRS may worsen liver dysfunction and deteriorate prognosis in liver cirrhosis by decreasing hepatic perfusion. METHODS: Patients with liver cirrhosis who were admitted to our department between December 2014 and August 2019 and underwent contrast-enhanced computed tomography or magnetic resonance imaging scans were prospectively collected. The maximum diameters of SSRS and portal vein system vessels were retrospectively measured. Liver-to-abdominal area ratio, Child-Pugh, and model for end-stage liver disease scores were calculated. RESULTS: Overall, 122 cirrhotic patients were included. The prevalence of SSRS was 30.3% (37/122). Median diameter of SSRS was 13.5 mm. Patients with SSRS had significantly thinner diameters of right portal vein (9 mm vs 11.2 mm, P = 0.001) and main portal vein (15.3 mm vs 16.8 mm, P = 0.017) than those without SSRS. Patients with SSRS had significantly lower liver-to-abdominal area ratio score (25.39 vs 31.58, P < 0.001) and higher Child-Pugh (7 vs 6, P = 0.046) and model for end-stage liver disease (12.17 vs 9.79, P < 0.006) scores than those without SSRS. Patients with SSRS had a significantly lower cumulative survival rate than those without SSRS (P = 0.014). Cox regression analysis also showed that SSRS was a risk factor of death of cirrhotic patients (hazard ratio = 4.161, 95% confidence interval = 1.215-14.255, P = 0.023). CONCLUSIONS: Spontaneous splenorenal shunt may narrow portal vein diameter and shrink liver volume, thereby worsening liver function and increasing mortality in liver cirrhosis.


Assuntos
Hipertensão Portal/etiologia , Cirrose Hepática/patologia , Fígado/patologia , Tamanho do Órgão , Veia Porta/patologia , Veias Renais , Veia Esplênica , Trombose Venosa/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Fatores de Tempo , Adulto Jovem
9.
Reproduction ; 159(2): 133-144, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31917674

RESUMO

Menstruation is a specific physiological phenomenon that occurs in women. However, molecular mechanisms underlying this phenomenon are still unclear. According to the classical theory, tissue hypoxia resulting from vasoconstriction of the spiral arteries after progesterone (P4) withdrawal initiates the breakdown of the endometrium at the earliest stage of menstruation. However, this theory has been challenged by previous studies that have questioned the function and even the existence of hypoxia during menstruation. In this study, we not only provide convincing evidence that hypoxia exists during endometrial breakdown, but also further explore the role of hypoxia and hypoxia-inducible factor 1 (HIF1) in this process. Based on mouse menstrual-like model and experiments with human decidual stromal cells, we observed that P4 withdrawal induced both hypoxia and HIF1 activation; however, endometrial breakdown was triggered only by P4 withdrawal. Hypoxia significantly enhanced the mRNA expression of specific matrix metalloproteinases (MMPs) under the conditions of P4 withdrawal. In conclusion, hypoxia is involved but not an essential component of endometrial breakdown during menstruation.


Assuntos
Hipóxia Celular/fisiologia , Endométrio/fisiologia , Menstruação/fisiologia , Animais , Decídua/citologia , Endométrio/irrigação sanguínea , Endométrio/química , Feminino , Expressão Gênica/fisiologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Metaloproteinases da Matriz/genética , Camundongos , Modelos Animais , Progesterona/administração & dosagem , Progesterona/fisiologia , Vasoconstrição
10.
BMC Cancer ; 20(1): 1029, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33109127

RESUMO

BACKGROUND: Cervical cancer is the leading cause of cancer-related death in women worldwide. However, the mechanisms mediating the development and progression of cervical cancer are unclear. In this study, we aimed to elucidate the roles of microRNAs and a1-chimaerin (CHN1) protein in cervical cancer progression. METHODS: The expression of miR-205 and CHN1 protein was investigated by in situ hybridisation and immunohistochemistry. We predicted the target genes of miR-205 using software prediction and dual luciferase assays. The expression of mRNAs and proteins was tested by qRT-PCR and western blotting respectively. The ability of cell growth, migration and invasion was evaluated by CCK-8 and transwell. Cell apoptosis was analysed by flow cytometry analysis. RESULTS: We found that miR-205 and CHN1 were highly expressed in human cervical cancer tissue compared with paired normal cervical tissues. The CHN1 gene was shown to be targeted by miR-205 in HeLa cells. Interestingly, transfection with miR-205 mimic upregulated CHN1 mRNA and protein, while miR-205 inhibitor downregulated CHN1 in high-risk and human papilloma virus (HPV)-negative human cervical cancer cells in vitro,. These data suggested that miR-205 positively regulated the expression of CHN1. Furthermore, the miR-205 mimic promoted cell growth, apoptosis, migration, and invasion in high-risk and HPV-negative cervical cancer cells, while the miR-205 inhibitor blocked these biological processes. Knockdown of CHN1 obviously reduced the aggressive cellular behaviours induced by upregulation of miR-205, suggesting that miR-205 positively regulated CHN1 to mediate these cell behaviours during the development of cervical cancer. Furthermore, CHN1 was correlated with lymph node metastasis in clinical specimens. CONCLUSIONS: Our findings showed that miR-205 positively regulated CHN1 to mediate cell growth, apoptosis, migration, and invasion during cervical cancer development, particularly for high-risk HPV-type cervical cancer. These findings suggested that dysregulation of miR-205 and subsequent abnormalities in CHN1 expression promoted the oncogenic potential of human cervical cancer.


Assuntos
Quimerina 1/genética , Metástase Linfática/genética , MicroRNAs/genética , Regulação para Cima , Neoplasias do Colo do Útero/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quimerina 1/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Neoplasias do Colo do Útero/metabolismo
11.
Ann Hepatol ; 19(5): 573-577, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31521463

RESUMO

Acute portomesenteric vein thrombosis is potentially lethal. In the present paper, a cirrhotic patient with a previous history of esophageal variceal bleeding presented with acute occlusive portomesenteric vein thrombosis, but achieved complete recanalization by low-molecular-weight heparin followed by rivaroxaban. Notably, no bleeding episode occurred during anticoagulation therapy. This case supported early initiation of anticoagulation in such patients.


Assuntos
Varizes Esofágicas e Gástricas/terapia , Inibidores do Fator Xa/uso terapêutico , Hemorragia Gastrointestinal/terapia , Hemostase Endoscópica , Heparina de Baixo Peso Molecular/uso terapêutico , Cirrose Hepática Alcoólica/complicações , Veias Mesentéricas , Veia Porta , Rivaroxabana/uso terapêutico , Trombose Venosa/tratamento farmacológico , Doença Aguda , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/etiologia , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Hemostase Endoscópica/efeitos adversos , Humanos , Cirrose Hepática Alcoólica/diagnóstico , Masculino , Veias Mesentéricas/diagnóstico por imagem , Pessoa de Meia-Idade , Veia Porta/diagnóstico por imagem , Resultado do Tratamento , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia
12.
J Environ Manage ; 276: 111315, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32911388

RESUMO

Climate change brings uncertainty and challenges to achieving sustainable development goals. The dually vulnerable regions in terms of the environment and economy are facing substantial threats from climate change; particularly, smallholder farmers who heavily rely on natural ecosystems in these regions are being the most affected. Paying attention to the vulnerability assessment of these regions is conducive to precisely improving the ability of their people to cope with climate change. This study aimed to construct an extended framework of climate change vulnerability assessment at the household level by combining the Intergovernmental Panel on Climate Change vulnerability assessment framework with the sustainable livelihood framework. Four typical regions with different climatic and geographical conditions in China, including the Inner Mongolia Autonomous Region (marked as AOHAN, representing the type of grassland, similarly hereinafter), Qinghai Province (HYMH, plateau), Yunnan Province (YLNL, mountain), and the Guangxi Zhuang Autonomous Region (NNQZ, coastal zone), were selected to apply the framework. In total, 29 villages from these four regions were selected at random, and 360 face-to-face interviews were conducted in selected villages based on a pretested questionnaire. The results show that AOHAN had the greatest vulnerability, as well as the highest exposure level among the four regions, which was also the major source of differences in vulnerability. Further analysis shows that although the sensitivity and adaptive capacity showed relatively small differences, the sources of sensitivity and adaptation strategies were quite different among the four regions. In terms of sensitivity, YLNL had the highest level of sensitivity in housing, water, and livestock, and AOHAN assumed the highest sensitivity in land. The advantages and disadvantages in terms of adaptive capacity also varied widely among the four regions. More specifically, AOHAN had a balanced adaptive capacity; YLNL largely relied on the advantages in social and human capitals to compensate for the disadvantage in physical capital; and the strengths in physical and financial capitals are the main sources of adaptive capacities for NNQZ and HYMH, respectively. In general, the vulnerability assessment framework proposed in this study provides guidelines for vulnerability assessments at the household level in the face of climate change. In addition, heterogeneous measures to cope with the threats of climate change should be put forward precisely, based on the climatic, geographical and socioeconomic characteristics of each region.


Assuntos
Mudança Climática , Fazendeiros , China , Ecossistema , Geografia , Humanos
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(12): 1273-1278, 2020 Dec.
Artigo em Zh | MEDLINE | ID: mdl-33327997

RESUMO

OBJECTIVE: To study the application of ponderal index (PI), body mass index (BMI), mid-arm circumference/head circumference (MAC/HC), and Clinical Assessment of Nutritional Status (CANS) score in assessing the nutritional status of neonates at birth, and to find a simple and reliable scheme for the assessment of fetal nutritional status. METHODS: PI, BMI, MAC/HC, and CANS were used to assess the nutritional status of full-term infants and preterm infants shortly after birth. The assessment results of these methods were analyzed. RESULTS: Among the 678 full-term infants, 61, 102, 47, and 131 were diagnosed with malnutrition by PI, BMI, MAC/HC, and CANS respectively. Among the 140 preterm infants, 30, 87, 9, and 112 were diagnosed with malnutrition by PI, BMI, MAC/HC, and CANS respectively. The combination of BMI and CANS had a detection rate of 99.3% in full-term infants and 100% in preterm infants. Compared with the single method, the combination significantly improved the detection rate of malnutrition (P < 0.05), while there was no significant difference between the combination of BMI+CANS and the combination of PI+BMI+CANS (P > 0.05). CONCLUSIONS: The combination of BMI+CANS can reduce the rate of missed diagnosis of fetal malnutrition. It is therefore a simple and reliable method for the assessment of fetal malnutrition.


Assuntos
Transtornos da Nutrição Fetal/diagnóstico , Avaliação Nutricional , Índice de Massa Corporal , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Estado Nutricional
14.
Reproduction ; 157(2): 149-161, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30601756

RESUMO

Stress impacts the reproductive axis at the level of the hypothalamus and the pituitary gland, which exert an effect on the ovary. Menstruation is regulated by the hypothalamic-pituitary-ovary (HPO) axis. However, the role of stress in menstruation remains unclear. The objective of this study was to explore the role of stress in endometrial breakdown and shedding, using the pseudopregnant mouse menstrual-like model. Female mice were mated with vasectomized males and labeled day 0.5, upon observation of a vaginal seminal plug. On day 3.5, decidualization was induced in pseudopregnant mice using arachis oil. On day 5.5, pseudopregnant mice with artificial decidualization were placed in restraint tubes for 3 h. The findings indicated that acute restraint stress resulted in the disintegration of the endometrium. While corticosterone concentration in the serum increased significantly due to restraint stress, follicle-stimulating hormone (FSH), luteinizing hormone (LH) and progesterone (P4) levels in the serum decreased significantly. An endometrial histology examination indicated that progesterone implants may rescue P4 decline caused by acute stress and block endometrium breakdown and shedding. In addition, mice were treated with metyrapone, an inhibitor of corticosterone synthesis, 1 h prior to being subjected to restraint stress. Interestingly, metyrapone not only inhibited stress-induced endometrium breakdown and shedding, but also prevented stress-induced reduction of P4, LH and FSH. Furthermore, real-time PCR and western blot showed that mRNA and protein expression of CYP11A1 (cytochrome P450, family 11, subfamily A, polypeptide 1) and steroidogenic acute regulatory protein (StAR), the two rate-limiting enzymes for progesterone synthesis in the ovary, decreased following acute stress. But metyrapone prevented the reduction of StAR expression induced by restraint stress. Overall, this study revealed that acute stress results in an increase in corticosterone, which may inhibit LH and FSH release in the serum and CYP11A1 and StAR expression in the ovary, which finally leads to the breakdown and shedding of the endometrium. These experimental findings, based on the mouse model, may enable further understanding of the effects of stress on menstruation regulation and determine the potential factors affecting stress-associated menstrual disorders.


Assuntos
Corticosterona/sangue , Endométrio/patologia , Progesterona/sangue , Estresse Fisiológico/fisiologia , Estresse Psicológico/patologia , Animais , Endométrio/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Metirapona/farmacologia , Camundongos , Progesterona/farmacologia , Restrição Física
15.
Sensors (Basel) ; 17(4)2017 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-28375189

RESUMO

Harmonic force and torque, which are caused by rotor imbalance and sensor runout, are the dominant disturbances in active magnetic bearing (AMB) systems. To eliminate the harmonic force and torque, a novel control method based on repetitive control and notch filters is proposed. Firstly, the dynamics of a four radial degrees of freedom AMB system is described, and the AMB model can be described in terms of the translational and rotational motions, respectively. Next, a closed-loop generalized notch filter is utilized to identify the synchronous displacement resulting from the rotor imbalance, and a feed-forward compensation of the synchronous force and torque related to the AMB displacement stiffness is formulated by using the identified synchronous displacement. Then, a plug-in repetitive controller is designed to track the synchronous feed-forward compensation adaptively and to suppress the harmonic vibrations due to the sensor runout. Finally, the proposed control method is verified by simulations and experiments. The control algorithm is insensitive to the parameter variations of the power amplifiers and can precisely suppress the harmonic force and torque. Its practicality stems from its low computational load.

16.
Mol Reprod Dev ; 83(9): 780-791, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27500900

RESUMO

Irregular uterine bleeding is a major side effect of long-acting progestogen-only contraceptives in women, and is the primary reason women discontinue their use. In this study, a mouse model of endometrial breakdown was established using a subcutaneous progesterone implant to understand how irregular bleeding begins. Although progestogens sustained decidualization, endometrial breakdown was still observed in this model. We, therefore, hypothesized that endometrial breakdown might involve functional progesterone withdrawal. Using co-immunoprecipitation assays, we observed the constitutive activation of nuclear factor kappa-b (NF-κB) p65 and its interaction with the progesterone receptor (PGR); moreover, transcriptional activity of the PGR was also repressed by NF-κB activity in primary mouse and human decidual stromal cells that mimic progesterone maintenance. Yet the ratio of PGR-B to PGR-A was not increased in the mouse model. In vivo comparison of endometrial breakdown induced by progesterone withdrawal to that seen during sustained progesterone exposure, in the presence of NF-κB inhibitors, revealed that NF-κB-mediated functional progesterone withdrawal is involved in endometrial breakdown in this implant model. These data prompt further studies to determine the homology of this functional progesterone withdrawal mechanism in human endometrium. Mol. Reprod. Dev. 83: 780-791, 2016 © 2016 Wiley Periodicals, Inc.


Assuntos
Anticoncepcionais Orais Hormonais/efeitos adversos , Endométrio , Progesterona/metabolismo , Fator de Transcrição RelA/metabolismo , Doenças Uterinas , Hemorragia Uterina , Animais , Anticoncepcionais Orais Hormonais/farmacologia , Modelos Animais de Doenças , Endométrio/metabolismo , Endométrio/patologia , Feminino , Camundongos , Receptores de Progesterona/metabolismo , Doenças Uterinas/induzido quimicamente , Doenças Uterinas/metabolismo , Doenças Uterinas/patologia , Hemorragia Uterina/induzido quimicamente , Hemorragia Uterina/metabolismo , Hemorragia Uterina/patologia
17.
Hum Reprod ; 30(9): 2160-70, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26113661

RESUMO

STUDY QUESTION: How is vascular endothelial growth factor (VEGF) expression regulated by hypoxia inducible factor 1 alpha (HIF1A) during menstruation? SUMMARY ANSWER: After progesterone (P4) withdrawal, HIF1A was activated and it directly up-regulated VEGF mRNA expression and this regulation was the highest during endometrium breakdown in the mouse menstrual-like model. WHAT IS KNOWN ALREADY: VEGF, an important angiogenic factor, is known to be essential for endometrial repair, particularly in angiogenesis and re-epithelialization. However, its upstream regulation has not been fully clarified. HIF1 is the first transcription factor response to hypoxia and is closely associated with angiogenesis; it is also an upstream regulator of VEGF mRNA. STUDY DESIGN, SIZE, DURATION: We investigated the changes in the expression of HIF1A and VEGF after P4 withdrawal and after HIF1A inhibition. The total number of mice used was 62. The treatment duration in the mouse menstrual-like model was 8 days. PARTICIPANTS/MATERIALS, SETTING, METHODS: The mouse menstrual-like model and mouse and human decidual endometrial stromal cells were established to mimic menstruation. Protein and mRNA expressions of HIF1A and VEGF were investigated by immunohistochemistry, Western blot and quantitative PCR. The direct interaction between HIF1A and the Vegf promoter was also investigated by chromatin immunoprecipitation. HIF1A inhibition in vivo and in vitro was achieved by administration of an HIF1A inhibitor and by siRNA knockdown, respectively. MAIN RESULTS AND THE ROLE OF CHANCE: HIF1A was translocated to the nucleus from 8 to 16 h after P4 withdrawal, while VEGF mRNA expression was the highest at 12 h. HIF1A directly bound to Vegf promoter during endometrial breakdown, which peaked at 12 h. HIF1A inhibition suppressed VEGF mRNA and protein expression in the mouse menstrual-like model and decidualized stromal cells. Inhibition of HIF1A also suppressed endometrial breakdown. LIMITATIONS, REASONS FOR CAUTION: Although HIF1A regulation of VEGF mRNA was confirmed in the mouse menstrual-like model and decidual endometrium stromal cells, the functional regulation of VEGF protein was not further determined. WIDER IMPLICATIONS OF THE FINDINGS: Here, we report that the functional regulation of VEGF was complicate in menstruation. We also report that HIF1A plays a key role in endometrial breakdown. STUDY FUNDING/COMPETING INTERESTS: The National Nature Science Foundation of China (No. 30901608), the National Basic Research Program of China (2010CB530403) and the National Science and Technology Support Program (No. 2012BAI32B05). The authors have no conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: This study is not a clinical trial.


Assuntos
Decídua/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Menstruação/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Feminino , Humanos , Camundongos , Modelos Animais , RNA Mensageiro/metabolismo
18.
Arch Environ Contam Toxicol ; 69(1): 1-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25600924

RESUMO

The toxic effects of the ubiquitous pollutant 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) on the earthworm Eisenia fetida were assessed by determining growth-inhibition and gene transcript levels of superoxide dismutase (SOD), catalase (CAT), glutathione transferase (GST), and transcriptional changes of the stress-response gene (heat-shock protein 70 [Hsp70]). Somatic growth and growth-inhibition rates in all BDE-47-treated groups were significantly different from those of the controls. The SOD gene transcripts were upregulated at all exposure doses and reached the maximum at the concentration of 400 mg/kg dry weight (dw) (3.84-fold, P < 0.01), which protected earthworms from oxidative stresses. However, downregulation of CAT and Hsp70 was present in all exposure doses and reached to the minimum at concentrations of 400 mg/kg dw (0.07-fold, P < 0.01 and 0.06-fold, P < 0.01, respectively). Upregulation of GST gene transcript level presented significant changes at concentrations of 10 (2.69-fold, P < 0.05) and 100 mg/kg dw (2.55-fold, P < 0.05). SOD maintained a dynamic balance to upregulate SOD expression to eliminate superoxide radicals in all dosage treatments, but downregulation of CAT decreased the ability to eliminate hydrogen peroxide. These changes could result in biochemical and physiological disturbances in earthworms.


Assuntos
Expressão Gênica/efeitos dos fármacos , Inibidores do Crescimento/toxicidade , Éteres Difenil Halogenados/toxicidade , Oligoquetos/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Animais , Catalase/metabolismo , Glutationa Transferase/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo
19.
Sensors (Basel) ; 15(9): 21876-97, 2015 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-26334281

RESUMO

Harmonic vibrations of high-speed rotors in momentum exchange devices are primary disturbances for attitude control of spacecraft. Active magnetic bearings (AMBs), offering the ability to control the AMB-rotor dynamic behaviors, are preferred in high-precision and micro-vibration applications, such as high-solution Earth observation satellites. However, undesirable harmonic displacements, currents, and vibrations also occur in the AMB-rotor system owing to the mixed rotor imbalances and sensor runout. To compensate the rotor imbalances and to suppress the harmonic vibrations, two control methods are presented. Firstly, a four degrees-of-freedom AMB-rotor model with the static imbalance, dynamic imbalance, and the sensor runout are described. Next, a synchronous current reduction approach with a variable-phase notch feedback is proposed, so that the rotor imbalances can be identified on-line through the analysis of the synchronous displacement relationships of the geometric, inertial, and rotational axes of the rotor. Then, the identified rotor imbalances, which can be represented at two prescribed balancing planes of the rotor, are compensated by discrete add-on weights whose masses are calculated in the vector form. Finally, a repetitive control algorithm is utilized to suppress the residual harmonic vibrations. The proposed field balancing and harmonic vibration suppression strategies are verified by simulations and experiments performed on a control moment gyro test rig with a rigid AMB-rotor system. Compared with existing methods, the proposed strategies do not require trial weights or an accurate model of the AMB-rotor system. Moreover, the harmonic displacements, currents, and vibrations can be well-attenuated simultaneously.

20.
Plant Biotechnol J ; 12(8): 1108-21, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24985700

RESUMO

MicroRNAs (miRNAs) are a class of regulatory small RNAs (sRNAs) that down-regulate target genes through mRNA cleavage or translational inhibition. miRNA is known to play an important role in the root development and environmental responses in both the Arabidopsis and rice. However, little information is available to form a complete view of miRNAs in the development of the maize root system and Al stress responses in maize. Four sRNA libraries were generated and sequenced from the early developmental stage of primary roots (PRY), the later developmental stage of maize primary roots (PRO), seminal roots (SR) and crown roots (CR). Through integrative analysis, we identified 278 miRNAs (246 conserved and 32 novel ones) and found that the expression patterns of miRNAs differed dramatically in different maize roots. The potential targets of the identified conserved and novel miRNAs were also predicted. In addition, our data showed that CR is more resistant to Al stress compared with PR and SR, and the differentially expressed miRNAs are likely to play significant roles in different roots in response to environmental stress such as Al stress. Here, we demonstrate that the expression patterns of miRNAs are highly diversified in different maize roots. The differentially expressed miRNAs are correlated with both the development and environmental responses in the maize root. This study not only improves our knowledge about the roles of miRNAs in maize root development but also reveals the potential role of miRNAs in the environmental responses of different maize roots.


Assuntos
Alumínio/toxicidade , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Raízes de Plantas/fisiologia , Estresse Fisiológico , Zea mays/fisiologia , Sequência de Bases , Análise por Conglomerados , Sequência Conservada , Relação Dose-Resposta a Droga , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/metabolismo , Dados de Sequência Molecular , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , RNA de Plantas/genética , RNA de Plantas/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Análise de Sequência de RNA , Zea mays/genética , Zea mays/crescimento & desenvolvimento
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