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1.
BMC Med Imaging ; 18(1): 47, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30477437

RESUMO

BACKGROUND: Spontaneous T2DM in rhesus monkeys manifests as isolated diastolic dysfunction in the early stage of diabetic cardiomyopathy, similar to humans. Myocardial deformation measurements have emerged as a superior way to measure left ventricular (LV) function in the early stage of cardiac dysfunction, making it possible to further evaluate early-stage LV dysfunction in spontaneous T2DM rhesus monkeys. METHODS: Spontaneous T2DM rhesus monkeys with isolated diastolic dysfunction (T2DM-DD, n = 10) and corresponding nondiabetic healthy animals (ND, n = 9) were prospectively scanned for a CMR study. Circumferential and longitudinal peak systolic strain (Ecc, Ell), time to peak strain (tEcc, tEll) and peak diastolic strain rate (CSR, LSR) obtained from 2D/3D CMR-TT were compared with those obtained from CMR tagging separately. In addition, all CMR imaging protocols were performed twice in 9 ND animals to assess test-retest reproducibility. RESULTS: Compared with the ND group, the T2DM-DD monkeys demonstrated significantly impaired LV Ecc (- 10.63 ± 3.23 vs - 14.18 ± 3.19, p < 0.05), CSR (65.50 ± 14.48 vs 65.50 ± 14.48, p < 0.01), Ell (- 9.11 ± 2.59 vs - 14.17 ± 1.68, p < 0.05), and LSR (59.43 ± 19.17 vs 108.46 ± 22.33, p < 0.01) with the tagging. Only Ecc (- 13.10 ± 2.47 vs - 19.03 ± 3.69, p < 0.01) and CSR (148.90 ± 31.27 vs 202.00 ± 51.88, p < 0.01) were significantly reduced with 2D CMR-TT, and only Ecc (- 13.77 ± 1.98 vs - 17.26 ± 3.78, p < 0.05) was significantly reduced with 3D CMR-TT. Moreover, 2D/3D CMR-TT-derived Ecc and CSR correlated with the corresponding tagging values collectively, with a statistically significant ICC value (p < 0.05). Test-retest repeatability analysis showed that most tagging-derived biomarkers had acceptable repeatability (p < 0.01). In addition, 2D CMR-TT-derived indicators were poorer than those derived from the tagging method but better than those obtained using the 3D method, with larger ICCs except for tEcc (p < 0.05). CONCLUSIONS: LV systolic and diastolic deformations were impaired in spontaneous T2DM rhesus monkeys previously diagnosed with isolated diastolic dysfunction by echocardiography. The 2D CMR-TT-derived Ecc and CSR were effective in the evaluation of the myocardial systolic and diastolic functions of early-diabetic cardiomyopathy, with relatively higher test-retest reproducibility and acceptable correlation with the tagging method compared with the 3D CMR-TT method.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Insuficiência Cardíaca Diastólica/diagnóstico por imagem , Insuficiência Cardíaca Diastólica/fisiopatologia , Imagem Cinética por Ressonância Magnética/métodos , Animais , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/fisiopatologia , Modelos Animais de Doenças , Humanos , Macaca mulatta , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda
2.
Toxicol Res (Camb) ; 13(4): tfae132, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39165832

RESUMO

Background: Sevoflurane (Sev), a widely used volatile anesthetic, can cause neurotoxicity, and impair learning and memory. Objective: This study investigates the role and mechanisms of circHIPK3 in Sev-exposed neurotoxicity and learning and memory impairment. Methods: SD rats and hippocampal neuronal cells were exposed to Sev. RT-qPCR analysis of circHIPK3 and miR-338-3p levels. MWM test was performed to examine the behavioral changes in rats. The levels of circHIPK3 and miR-338-3p levels were investigated using RT-qPCR. ELISA assay to analyze the expression of pro-inflammatory factors. CCK-8, flow cytometry, and commercial ROS assay kits were analyzed to detect cell viability, apoptosis, and ROS production. DLR and RIP assays validate circHIPK3 binding to miR-338-3p. Results: Sev increased circHIPK3 expression in rat hippocampal tissue as well as in neuronal cells but decreased miR-338-3p levels compared to controls. circHIPK3 binding to miR-338-3p. Furthermore, silencing of circHIPK3 rats attenuated Sev-induced decline in learning and memory functions . silencing circHIPK3 also reduced Sev-induced secretion of inflammatory factors in rat and neuronal cells. Reducing circHIPK3 partially reversed the Sev-induced decrease in cell viability, increased apoptosis, and overproduction of ROS. However, the inhibitory effect of circHIPK3 on Sev neurotoxicity was restored upon downregulation of miR-338-3p. Conclusion: Collectively, silencing circHIPK3 alleviates Sev exposure-induced learning and memory deficits and neurotoxicity by enhancing miR-338-3p expression.

3.
Head Face Med ; 20(1): 28, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730461

RESUMO

BACKGROUND: Few studies have examined the otologic symptoms of Coronavirus disease 2019 (COVID-19). The objective of this study was to identify the effect of COVID-19 on the characteristics and outcomes of patients who have otitis media with effusion (OME). METHODS: This case-control study compared the characteristics and outcomes of OME patients who did or did not have COVID-19. A total of 65 patients with previous COVID-19 and 40 patients who did not have COVID-19 (controls) were enrolled from October 1, 2022 to January 31, 2023 at a single institution in China. Demographics, medical histories, morbidities, hearing test results, treatments, and outcomes of the two groups were compared. RESULTS: The COVID-19 group had significantly better outcomes from OME than the control group, with higher rates of complete resolution (64.6% vs. 30%) and improvement (30.8% vs. 17.5%), and a lower rate of persistent OME (4.6% vs. 52.5%). Previous COVID-19 was independently associated with a more favorable OME outcome in three multivariate logistic regression models. The COVID-19 group also had a greater improvement in hearing threshold based on air-bone gap measurements. CONCLUSION: The outcomes of OME patients who had previous COVID-19 were generally good, in that most patients responded well to treatment and achieved complete resolution or improvement within one month.


Assuntos
COVID-19 , Otite Média com Derrame , Humanos , COVID-19/epidemiologia , COVID-19/complicações , Masculino , Feminino , Estudos de Casos e Controles , Pessoa de Meia-Idade , Adulto , China/epidemiologia , SARS-CoV-2 , Idoso , Resultado do Tratamento , Estudos Retrospectivos , Pandemias
4.
Comput Biol Med ; 177: 108660, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820774

RESUMO

Omics-based technologies have revolutionized our comprehension of microproteins encoded by ncRNAs, revealing their abundant presence and pivotal roles within complex functional landscapes. Here, we developed MicroProteinDB (http://bio-bigdata.hrbmu.edu.cn/MicroProteinDB), which offers and visualizes the extensive knowledge to aid retrieval and analysis of computationally predicted and experimentally validated microproteins originating from various ncRNA types. Employing prediction algorithms grounded in diverse deep learning approaches, MicroProteinDB comprehensively documents the fundamental physicochemical properties, secondary and tertiary structures, interactions with functional proteins, family domains, and inter-species conservation of microproteins. With five major analytical modules, it will serve as a valuable knowledge for investigating ncRNA-derived microproteins.


Assuntos
Bases de Dados de Proteínas , RNA não Traduzido , RNA não Traduzido/química , RNA não Traduzido/genética , Humanos , Proteínas/química , Animais , Micropeptídeos
5.
Disaster Med Public Health Prep ; 18: e68, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618875

RESUMO

OBJECTIVE: The COVID-19 pandemic has had a globally devastating psychosocial impact. A detailed understanding of the mental health implications of this worldwide crisis is critical for successful mitigation of and preparation for future pandemics. Using a large international sample, we investigated in the present study the relationship between multiple COVID-19 parameters (both disease characteristics and government responses) and the incidence of the suicide crisis syndrome (SCS), an acute negative affect state associated with near-term suicidal behavior. METHODS: Data were collected from 5528 adults across 10 different countries in an anonymous web-based survey between June 2020 and January 2021. RESULTS: Individuals scoring above the SCS cut-off lived in countries with higher peak daily cases and deaths during the first wave of the pandemic. Additionally, the longer participants had been exposed to markers of pandemic severity (eg, lockdowns), the more likely they were to screen positive for the SCS. Findings reflected both country-to-country comparisons and individual variation within the pooled sample. CONCLUSION: Both the pandemic itself and the government interventions utilized to contain the spread appear to be associated with suicide risk. Public policy should include efforts to mitigate the mental health impact of current and future global disasters.


Assuntos
COVID-19 , Suicídio , Adulto , Humanos , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Pandemias , Governo , Síndrome
6.
J Affect Disord ; 329: 1-8, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36828142

RESUMO

BACKGROUND: The Suicide Crisis Syndrome (SCS) has been proposed as an acute, pre-suicidal mental state that precedes imminent suicidal behavior; however, its cross-national applicability and sociodemographic correlates have not yet been determined. The present study assessed the presence and severity of the SCS in ten countries and examined several potential sociodemographic correlates (i.e., age, gender, marital status, race/ethnicity) of the SCS. METHODS: 5528 community-based adults across 10 participating countries provided information on their SCS symptoms and sociodemographic characteristics in an anonymous online survey obtained via convenience sampling during the first year of the COVID-19 pandemic. RESULTS: The SCS occurred cross-nationally, with rates ranging from 3.6% (Israel) to 16.2% (Poland). Those in the United States, South Korea, Poland, and Turkey had the highest severity of symptoms. Participants who were older, identified as cisgender men, and married tended to have lower rates of the SCS than their respective counterparts. There were minimal differences in the SCS by race/ethnicity. LIMITATIONS: These data were both cross-sectional and collected via convenience sampling, limiting generalizability of findings and information about the SCS's predictive utility. CONCLUSIONS: These findings support the cross-national presence of the SCS during the COVID-19 pandemic. Sociodemographic correlates aligned with those of suicidal behavior more generally, providing additional evidence for the concurrent/predictive validity of the SCS.


Assuntos
COVID-19 , Suicídio , Adulto , Masculino , Humanos , Estados Unidos/epidemiologia , Tentativa de Suicídio , Estudos Transversais , Pandemias , Ideação Suicida , Fatores de Risco
8.
Front Pharmacol ; 13: 1017433, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353495

RESUMO

Background: Heart failure (HF), the final stage of cardiovascular diseases, is a clinical syndrome of cardiac structural or functional abnormalities. QiShenYiQi Dripping Pills (T101), short for QSYQ (T101), showed effectiveness and safety in the treatment of HF according to modern pharmacological research and clinical studies, but the mechanism remains unclear. This study aims to clarify the mechanism of QSYQ (T101) in treating heart failure through the analysis to critical biomarkers, targets and pathways. Materials and Methods: In this study, the efficacies of QSYQ (T101) in non-human primates and rodents were evaluated, and the mechanism was demonstrated by integrating network pharmacology and metabolomics analysis. Furthermore, the targets from network pharmacology and the metabolites from targeted metabolomics were jointly analyzed to screen the critical pathways. Results: In rhesus monkeys with spontaneous chronic heart failure, nasogastric administration of QSYQ (T101) for 12 weeks caused profound improvement of systolic and diastolic function as evidenced by echocardiography detection. Consistently, QSYQ (T101) administration especially with higher dose lowered the blood pressure and improved the ventricular remodeling, collagen deposition and fibrosis markedly in Spontaneous Hypertension Rats (SHR) model. Computational prediction showed that QSYQ (T101) exhibited anti-HF effects possibly through HIF-1 signaling pathway, FoxO signaling pathway, TNF signaling pathway, PI3K-Akt signaling pathway and other enriched paths. Metabolomics analysis obtained 23 significantly altered metabolites, revealing that QSYQ (T101) significantly regulated the abnormal levels of fatty acids, carnitines, organic acids pyridines, nucleosides, which were mostly involved in myocardial energy metabolism related pathways. Conclusion: Based on serum and myocardium metabolomics and network pharmacology, the present study revealed that the actions of QSYQ (T101) in treating HF depend on multi-components, multi-targets and multi-pathways.

9.
J Endocrinol ; 248(2): 145-154, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33258802

RESUMO

Glucagon-like peptide 1 (GLP-1) is an insulinotropic hormone and plays an important role in regulating glucose homeostasis. GLP-1 has a short half-life (t1/2 < 2 min) due to degrading enzyme dipeptidyl peptidase-IV and rapid kidney clearance, which limits its clinical application as a therapeutic reagent. We demonstrated recently that supaglutide, a novel GLP-1 mimetic generated by recombinant fusion protein techniques, exerted hypoglycemic and ß-cell trophic effects in type 2 diabetes db/db mice. In the present study, we examined supaglutide's therapeutic efficacy and pharmacokinetics in diabetic rhesus monkeys. We found that a single subcutaneous injection of supaglutide of tested doses transiently and significantly reduced blood glucose levels in a dose-dependent fashion in the diabetic monkeys. During a 4-week intervention period, treatment of supaglutide of weekly dosing dose-dependently decreased fasting and random blood glucose levels. This was associated with significantly declined plasma fructosamine levels. The repeated administration of supaglutide remarkably also decreased body weight in a dose-dependent fashion accompanied by decreased food intake. Intravenous glucose tolerance test results showed that supaglutide improved glucose tolerance. The intervention also showed enhanced glucose-stimulated insulin secretion and improved lipid profile in diabetic rhesus monkeys. These results reveal that supaglutide exerts beneficial effects in regulating blood glucose and lipid homeostasis in diabetic rhesus monkeys.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Avaliação Pré-Clínica de Medicamentos , Insulina/sangue , Secreção de Insulina/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Macaca mulatta , Masculino
10.
Acta Diabetol ; 57(6): 673-679, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31938886

RESUMO

AIMS: To investigate the correlation of impairment in skeletal muscle and heart in spontaneous type 2 diabetes mellitus (T2DM) rhesus monkeys using magnetic resonance image (MRI). METHODS: Fifteen T2DM monkeys and fourteen healthy control (HC) monkeys were included. The microcirculation of skeletal muscle [skeletal muscle blood flow (SMBF), skeletal muscle oxygen extraction fraction (SMOEF)] and the function and strain of heart were evaluated by MRI. Three regions of interests were chosen on the soleus muscle (SOL), gastrocnemius muscle (GAS) and tibialis anterior muscle (TA) for image analysis. RESULTS: Eight T2DM monkeys and eight HC monkeys were obtained the full data. The SMBF reserves and SMOEF reserves were found significantly decreased in T2DM during inflation in SOL, GAS and TA muscles (all p < 0.05), and the SMBF reserves decreased during hyperemia in GAS and TA muscles (all p < 0.05). In these monkeys, the global peak longitudinal strain (longitudinal PS), peak systolic longitudinal strain rate (longitudinal PSSR) and peak diastolic longitudinal strain rate (longitudinal PDSR) were seen significantly different in T2DM compared to HC monkeys (all p < 0.05). The longitudinal PSSR was found negatively correlated with SMBF reserves in SOL, GAS and TA during inflation in all monkeys. CONCLUSIONS: The impaired microcirculation of skeletal muscle and the myocardial deformation were found in T2DM monkeys with normal ejection fraction. And a negative correlation was existed in the longitudinal PSSR and the SMBF reserves.


Assuntos
Diabetes Mellitus Tipo 2 , Modelos Animais de Doenças , Coração/diagnóstico por imagem , Macaca mulatta , Imageamento por Ressonância Magnética , Músculo Esquelético/diagnóstico por imagem , Animais , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/patologia , Angiopatias Diabéticas/fisiopatologia , Feminino , Coração/fisiopatologia , Humanos , Masculino , Microcirculação/fisiologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Miocárdio/patologia , Fluxo Sanguíneo Regional
11.
J Immunol Methods ; 332(1-2): 121-8, 2008 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-18242638

RESUMO

Using sera from atopic patients we have isolated an extracellular protein, which is antigenic in humans, from Stachybotrys chartarum sesu lato. Here we report the production of monoclonal antibodies to the protein and the development of a sensitive and specific assay to the target protein as well as analyses in house dust samples spiked with spores. The detection limit for the target antigen in house dust was approximately 0.2 ng/g dry weight house dust. This detection limit is comparable to those for house dust mite allergen and the allergen of the fungus Aspergillus fumigatus but lower than that for the fungus Alternaria alternata.


Assuntos
Anticorpos Monoclonais/química , Antígenos de Fungos/análise , Poeira/análise , Proteínas Fúngicas/análise , Stachybotrys/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Reações Antígeno-Anticorpo , Antígenos de Fungos/imunologia , Western Blotting , Poeira/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Proteínas Fúngicas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Reprodutibilidade dos Testes , Esporos Fúngicos/química , Esporos Fúngicos/imunologia
12.
Materials (Basel) ; 10(10)2017 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-28946690

RESUMO

To investigate the performance of bonding on the interface between ZChSnSb/Sn and steel body, the interfacial bonding energy on the interface of a ZChSnSb/Sn alloy layer and the steel body with or without Sn as an intermediate layer was calculated under the same loadcase using the molecular dynamics simulation software Materials Studio by ACCELRYS, and the interfacial bonding energy under different Babbitt thicknesses was compared. The results show that the bonding energy of the interface with Sn as an intermediate layer is 10% larger than that of the interface without a Sn layer. The interfacial bonding performances of Babbitt and the steel body with Sn as an intermediate layer are better than those of an interface without a Sn layer. When the thickness of the Babbitt layer of bushing is 17.143 Å, the interfacial bonding energy reaches the maximum, and the interfacial bonding performance is optimum. These findings illustrate the bonding mechanism of the interfacial structure from the molecular level so as to ensure the good bonding properties of the interface, which provides a reference for the improvement of the bush manufacturing process from the microscopic point of view.

13.
Am J Trop Med Hyg ; 90(6): 1176-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24639299

RESUMO

Dirofilaria immitis (heartworm) is the causative agent of an important zoonotic disease that is spread by mosquitoes. In this study, molecular and phylogenetic characterization of D. immitis were performed based on complete ND1 and 16S rDNA gene sequences, which provided the foundation for more advanced molecular diagnosis, prevention, and control of heartworm diseases. The mutation rate and evolutionary divergence in adult heartworm samples from seven dogs in western China were analyzed to obtain information on genetic diversity and variability. Phylogenetic relationships were inferred using both maximum parsimony (MP) and Bayes methods based on the complete gene sequences. The results suggest that D. immitis formed an independent monophyletic group in which the 16S rDNA gene has mutated more rapidly than has ND1.


Assuntos
Dirofilaria immitis/genética , Dirofilariose/parasitologia , Doenças do Cão/parasitologia , Variação Genética , Animais , Sequência de Bases , China/epidemiologia , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Dirofilaria immitis/classificação , Dirofilaria immitis/isolamento & purificação , Dirofilariose/diagnóstico , Dirofilariose/epidemiologia , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Cães , Evolução Molecular , Proteínas de Helminto/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Alinhamento de Sequência , Análise de Sequência de DNA/veterinária
14.
J Wildl Dis ; 49(4): 1052-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24502740

RESUMO

The helminth Baylisascaris schroederi is one of the most harmful parasites infecting giant pandas (Ailuropoda melanoleuca). It is therefore important to develop an exact diagnostic technique to detect this parasite. Using a known number (1, 2, 3, 4, 5, 10, 25, 50, 100) of feces-isolated B. schroederi egg and adult DNA, we developed a PCR to detect a portion of the mitochondrial 12S rRNA and applied it to giant panda fecal samples. The method was sufficiently sensitive to detect B. schroederi DNA from isolated eggs in a fecal sample with a detection threshold of one egg. We detected B. schroederi in 88% of fecal samples, 30% higher than the conventional flotation technique. No cross-reactivity with other common nematode DNA was detected. Our PCR assay may constitute a valuable alternative for the diagnosis of B. schroederi infections.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Ursidae , Animais , Infecções por Ascaridida/diagnóstico , Infecções por Ascaridida/parasitologia , Ascaridoidea/genética , DNA de Helmintos/genética , Fezes/parasitologia , Reação em Cadeia da Polimerase/métodos
15.
Parasitol Int ; 62(5): 435-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23688803

RESUMO

Baylisascaris schroederi is one of the most common intestinal nematodes in giant pandas. It can cause severe baylisascariasis which is highly infectious in its natural hosts. A rapid and reliable diagnosis of parasite infections is crucial to protect giant pandas, as well as for environmental monitoring and disease surveillance. Here, we established a specific PCR assay for B. schroederi detection which was targeting a 331-bp long fragment of the mitochondrial cytochrome c oxidase subunit II (COII) gene. Fifty fresh fecal samples collected from captive giant pandas were tested by the established PCR assay and the traditional flotation technique. DNA extracted from a single B. schroederi egg could be successfully amplified, while no cross-reactivity was found with DNA from Ancylostoma caninum eggs. The detection rate of the PCR assay was 68%, which was higher than that of the traditional egg flotation (46%). Our findings demonstrated that the PCR assay is sensitive and specific for the detection and identification of B. schroederi eggs. Therefore, it could become a useful tool for the investigation of B. schroederi infections in giant pandas.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Fezes/parasitologia , Reação em Cadeia da Polimerase/veterinária , Ursidae , Animais , Infecções por Ascaridida/parasitologia , Ascaridoidea/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/isolamento & purificação , Mitocôndrias/enzimologia , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade
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