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1.
Ecotoxicol Environ Saf ; 273: 116157, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430578

RESUMO

Arbuscular mycorrhizal fungi (AMF) and plant growth-promoting bacteria enhance plant tolerance to abiotic stress and promote plant growth in contaminated soil. However, the interaction mechanism between rhizosphere microbial communities under chromium (Cr) stress remains unclear. This study conducted a greenhouse pot experiment and metagenomics analysis to reveal the comprehensive effects of the interaction between AMF (Rhizophagus intraradices) and nitrogen-N metabolizing plant growth promoters on the growth of Iris tectorum. The results showed that AMF significantly increased the biomass and nutrient levels of I. tectorum in contaminated soil and decreased the content of Cr in the soil. Metagenomics analysis revealed that the structure and composition of the rhizosphere microbial community involved in nitrogen metabolism changed significantly after inoculation with AMF under Cr stress. Functional genes related to soil nitrogen mineralization (gltB, gltD, gdhA, ureC, and glnA), nitrate reduction to ammonium (nirB, nrfA, and nasA), and soil nitrogen assimilation (NRT, nrtA, and nrtC) were up-regulated in the N-metabolizing microbial community. In contrast, the abundance of functional genes involved in denitrification (nirK and narI) was down-regulated. In addition, the inoculation of AMF regulates the synergies between the N-metabolic rhizosphere microbial communities and enhances the complexity and stability of the rhizosphere ecological network. This study provides a basis for improving plant tolerance to heavy metal stress by regulating the functional abundance of N-metabolizing plant growth-promoting bacteria through AMF inoculation. It helps to understand the potential mechanism of wetland plant remediation of Cr-contaminated soil.


Assuntos
Iris (Planta) , Micorrizas , Micorrizas/metabolismo , Cromo/metabolismo , Iris (Planta)/genética , Plantas , Bactérias , Solo/química , Nitrogênio/metabolismo , Raízes de Plantas , Fungos
2.
PeerJ ; 11: e15681, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37953782

RESUMO

To investigate changes in fungal community characteristics under different Cr(VI) concentration stresses and the advantages of adding arbuscular mycorrhizal fungi (AMF), we used high throughput sequencing to characterize the fungal communities. Cr(VI) stress reduced rhizosphere soil SOM (soil organic matter) content and AMF addition improved this stress phenomenon. There were significant differences in fungal community changes under different Cr(VI) concentrations. The fungal community characteristics changed through inhibition of fungal metabolic ability, as fungal abundance increased after AMF addition, and the fungal diversity increased under high Cr(VI) concentration. The dominant phyla were members of the Ascomycota, Basidiomycota, Mortierellomycota, and Rozellomycota. Dominant groups relevant to Cr resistance were Ascomycota and Basidiomycota fungi. Moreover, Fungal community characteristics were analyzed using high-throughput sequencing of the cytochrome c metabolic pathway, NADH dehydrogenase, and NADH: ubiquinone reductase and all these functions were enhanced after AMF addition. Therefore, Cr(VI) stress significantly affects fungal community structure, while AMF addition could increase its SOM content, and metabolic capacity, and improve fungal community tolerance to Cr stress. This study contributed to the understanding response of rhizosphere fungal community in AMF-assisted wetland phytoremediation under Cr stress.


Assuntos
Acorus , Micobioma , Micorrizas , Micorrizas/genética , Rizosfera , Raízes de Plantas/microbiologia , Solo/química
3.
Heliyon ; 9(11): e21986, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027633

RESUMO

Introduction: Alexithymia and perceived stress have been recognized as risk factors for suicide in patients with major depressive disorder (MDD). However, few studies have been conducted to examine the relationship between these factors. Methods: A cross-sectional study was conducted on 105 MDD patients. Alexithymia was assessed by the 20-Item Toronto Alexithymia Scale (TAS), perceived stress was assessed by the Perceived Stress Scale (PSS), severity of depression was assessed by the 17-item Hamilton Depression Rating Scale (HAMD), and suicidal ideation was assessed by the self-report Beck Scale for Suicide Ideation (SSI). A sequential mediation model was established to test the mediating effects of perceived stress and severity of depression on the association between alexithymia and suicidal ideation. Results: 81 of the 105 participants (77.14 %) had suicidal ideation. Patients with suicidal ideation had greater difficulty in identifying feelings (DIF) (p = 0.046), higher severity of depression (p = 0.005) and perceived stress (p = 0.003). DIF subscale score of TAS was associated with perceived stress (r = 0.292, p = 0.003), severity of depression (r = 0.349, p < 0.001) and suicidal ideation (r = 0.229, p = 0.012). Sequential mediation model showed that perceived stress and severity of depression mediated the effect of DIF on suicidal ideation. Conclusions: This study suggests that perceived stress and severity of depression fully mediate the relationship between difficulty in identifying feelings and suicidal ideation in MDD patients.

4.
Front Microbiol ; 14: 1187982, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37655347

RESUMO

It is of positive significance to explore the mechanism of antioxidant and metabolic response of Canna indica under Cr stress mediated by rhizosphere niche. However, the mechanisms of recruitment and interaction of rhizosphere microorganisms in plants still need to be fully understood. This study combined physiology, microbiology, and metabolomics, revealing the interaction between C. indica and rhizosphere microorganisms under Cr stress. The results showed that Cr stress increased the content of malondialdehyde (MDA) and oxygen-free radicals (ROS) in plants. At the same time, the activities of antioxidant enzymes (SOD, POD, and APX) and the contents of glutathione (GSH) and soluble sugar were increased. In addition, Cr stress decreased the α diversity index of C. indica rhizosphere bacterial community and changed its community structure. The dominant bacteria, namely, Actinobacteriota, Proteobacteria, and Chloroflexi accounted for 75.16% of the total sequence. At the same time, with the extension of stress time, the colonization amount of rhizosphere-dominant bacteria increased significantly, and the metabolites secreted by roots were associated with the formation characteristics of Proteobacteria, Actinobacteria, Bacteroidetes, and other specific bacteria. Five critical metabolic pathways were identified by metabolome analysis, involving 79 differentially expressed metabolites, which were divided into 15 categories, mainly including lipids, terpenoids, and flavonoids. In conclusion, this study revealed the recruitment and interaction response mechanism between C. indica and rhizosphere bacteria under Cr stress through multi-omics methods, providing the theoretical basis for the remediation of Cr-contaminated soil.

5.
Ecotoxicol Environ Saf ; 263: 115218, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37441947

RESUMO

Chromium (Cr) is a toxic heavy element that interferes with plant metabolite biosynthesis and modifies the plant rhizosphere microenvironment, affecting plant growth. However, the interactions and response mechanisms between plants and rhizosphere bacteria under Cr stress still need to be fully understood. In this study, we used Iris tectorum as a research target and combined physiology, metabolomics, and microbiology to reveal the stress response mechanism of I. tectorum under heavy metal chromium stress. The results showed that Cr stress-induced oxidative stress inhibited plant growth and development and increased malondialdehyde and oxygen free radicals content. Also, it increased ascorbate peroxidase, peroxidase activity, and superoxide dismutase activity, as well as glutathione and soluble sugar content. Microbiome analysis showed that Cr stress changed the rhizosphere bacterial community diversity index by 33.56%. Proteobacteria, Actinobacteriota, and Chloroflexi together accounting for 71.21% of the total sequences. Meanwhile, the abundance of rhizosphere dominant and plant-promoting bacteria increased significantly with increasing time of Cr stress. The improvement of the soil microenvironment and the recruitment of bacteria by I. tectorum root secretions were significantly enhanced. By metabolomic analysis, five vital metabolic pathways were identified, involving 89 differentially expressed metabolites, divided into 15 major categories. In summary, a multi-omics approach was used in this study to reveal the interaction and stress response mechanisms between I. tectorum and rhizosphere bacterial communities under Cr stress, which provided theoretical basis for plant-microbial bioremediation of Cr-contaminated soils in constructed wetlands. This may provide more valuable information for wetland remediation of heavy metal pollution.


Assuntos
Iris (Planta) , Metais Pesados , Microbiota , Poluentes do Solo , Cromo/toxicidade , Cromo/metabolismo , Iris (Planta)/metabolismo , Rizosfera , Microbiologia do Solo , Metais Pesados/toxicidade , Bactérias/metabolismo , Solo , Poluentes do Solo/análise
6.
Sci Total Environ ; 895: 164970, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37343864

RESUMO

Chromium (Cr) can disrupt a plant's normal physiological and metabolic functions and severely impact the microenvironment. However, limited studies have investigated the impact of arbuscular mycorrhizal fungi (AMF) inoculation on the rhizosphere microorganisms of Iris tectorum under Cr stress, and the mechanisms of how rhizosphere microorganisms interact with hosts and contaminants. In this study, we investigated the effects of AMF inoculation on the growth, absorption of nutrients and heavy metals, and functional genes of the rhizosphere microbial community of I. tectorum under Cr stress in a greenhouse pot experiment. The results showed that AMF significantly increased the biomass and nutrient levels of I. tectorum, while decreasing the content of Cr in soil. Furthermore, metagenome analysis demonstrated significant changes in the structure and composition of the rhizosphere microbial community after AMF formed a mycorrhizal symbiosis system with the I. tectorum. Specifically, the abundance of functional genes related to nutrient cycling (N, P) and heavy metal resistance (chrA and arsB), as well as the abundance of heavy metal transporter family (P-atPase, MIT, CDF, and ABC) in the rhizosphere microbial community were up-regulated and their expression. Additionally, the synergies between rhizosphere microbial communities were regulated, and the complexity and stability of the rhizosphere microbial ecological network were enhanced. This study provides evidence that AMF can regulate rhizosphere microbial communities to improve plant growth and heavy metal stress tolerance, and helps us to understand the potential mechanism of wetland plant remediation of Cr-contaminated soil under AMF symbiosis.


Assuntos
Iris (Planta) , Metais Pesados , Microbiota , Micorrizas , Micorrizas/fisiologia , Cromo/análise , Raízes de Plantas/microbiologia , Rizosfera , Metagenômica , Metais Pesados/análise , Solo/química , Expressão Gênica , Microbiologia do Solo , Fungos
7.
J Affect Disord ; 319: 336-343, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36084757

RESUMO

Dynamic functional network connectivity (dFNC) could capture temporal features of spontaneous brain activity during MRI scanning, and it might be a powerful tool to examine functional brain network alters in major depressive disorder (MDD). Therefore, this study investigated the changes in temporal properties of dFNC of first-episode, drug-naïve patients with MDD. A total of 48 first-episode, drug-naïve MDD patients and 46 age- and gender-matched healthy controls were recruited in this study. Sliding windows were implied to construct dFNC. We assessed the relationships between altered dFNC temporal properties and depressive symptoms. Receiver operating characteristic (ROC) curve analyses were used to examine the diagnostic performance of these altered temporal properties. The results showed that patients with MDD have more occurrences and spent more time in a weak connection state, but with fewer occurrences and shorter dwell time in a strong connection state. Importantly, the fractional time and mean dwell time of state 2 was negatively correlated with Hamilton Depression Rating Scale (HDRS) scores. ROC curve analysis demonstrated that these temporal properties have great identified power including the fractional time and mean dwell time in state 2, and the AUC is 0.872, 0.837, respectively. The AUC of the combination of fractional time and mean dwell time in state 2 with age, gender is 0.881. Our results indicated the temporal properties of dFNC are altered in first-episode, drug-naïve patients with MDD, and these changes' properties could serve as a potential biomarker in MDD.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodos
8.
Biomed Res Int ; 2021: 4989297, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34950733

RESUMO

OBJECTIVE: Deep vein thrombosis (DVT) is the third-largest cardiovascular disease, and accurate segmentation of venous thrombus from the black-blood magnetic resonance (MR) images can provide additional information for personalized DVT treatment planning. Therefore, a deep learning network is proposed to automatically segment venous thrombus with high accuracy and reliability. METHODS: In order to train, test, and external test the developed network, total images of 110 subjects are obtained from three different centers with two different black-blood MR techniques (i.e., DANTE-SPACE and DANTE-FLASH). Two experienced radiologists manually contoured each venous thrombus, followed by reediting, to create the ground truth. 5-fold cross-validation strategy is applied for training and testing. The segmentation performance is measured on pixel and vessel segment levels. For the pixel level, the dice similarity coefficient (DSC), average Hausdorff distance (AHD), and absolute volume difference (AVD) of segmented thrombus are calculated. For the vessel segment level, the sensitivity (SE), specificity (SP), accuracy (ACC), and positive and negative predictive values (PPV and NPV) are used. RESULTS: The proposed network generates segmentation results in good agreement with the ground truth. Based on the pixel level, the proposed network achieves excellent results on testing and the other two external testing sets, DSC are 0.76, 0.76, and 0.73, AHD (mm) are 4.11, 6.45, and 6.49, and AVD are 0.16, 0.18, and 0.22. On the vessel segment level, SE are 0.95, 0.93, and 0.81, SP are 0.97, 0.92, and 0.97, ACC are 0.96, 0.94, and 0.95, PPV are 0.97, 0.82, and 0.96, and NPV are 0.97, 0.96, and 0.94. CONCLUSIONS: The proposed deep learning network is effective and stable for fully automatic segmentation of venous thrombus on black blood MR images.


Assuntos
Imageamento por Ressonância Magnética/métodos , Trombose/diagnóstico por imagem , Veias/diagnóstico por imagem , Aprendizado Profundo , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Reprodutibilidade dos Testes
9.
Quant Imaging Med Surg ; 11(1): 276-289, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33392028

RESUMO

BACKGROUND: Black-blood thrombus imaging (BTI) has shown to be advantageous for the diagnosis of deep vein thrombosis (DVT). However, previous techniques using fast spin echo have a high specific absorption rate. As DANTE (delay alternating with nutation for tailored excitation) black-blood preparation can suppress blood flows over a broad range of velocities, we hypothesized that a DANTE black-blood preparation combined with a fast low-angle shot (FLASH) gradient-echo readout-DANTE-FLASH could be used to diagnose DVT. METHODS: Eleven healthy volunteers and 30 suspected DVT patients were recruited to undergo DANTE-FLASH and magnetic resonance direct thrombus imaging (MRDTI). The suspected DVT patients were also examined by ultrasound (US). For the segment level, a total of 1,066 venous vessel segments were analyzed. Using US and MRDTI as the references, the sensitivity (SE), specificity (SP), positive and negative predictive values (PPV and NPV), and accuracy (ACC) of DANTE-FLASH were calculated. To quantitatively compare image quality between DANTE-FLASH and MRDTI, image signal-to-noise ratio (SNR), apparent contrast-to-noise ratio (CNR) between muscle and the venous lumen, and the apparent CNR between the thrombus and venous lumen were measured. Additionally, diagnostic confidence, image quality, and clot burden were also evaluated. RESULTS: Using the consensus results of US and MRDTI as a standard reference, the diagnostic SE, SP, PPV, NPV, and ACC of DANTE-FLASH for the 2 readers were 97.0% and 93.2%, 99.0% and 98.2%, 93.4% and 87.9%, 99.6% and 99.0%, and 98.8% and 97.6%, respectively. According to the image quantitative analysis results, DANTE-FLASH demonstrated higher image SNR and CNR than MRDTI. The image quality and diagnostic confidence scores of DANTE-FLASH were higher than MRDTI (3.66±0.44 vs. 3.52±0.52, P<0.001, and 3.84±0.36 vs. 3.76±0.41, P<0.001). There was excellent agreement between DANTE-FLASH and MRDTI on clot burden evaluation. CONCLUSIONS: DANTE-FLASH provided better image quality than MRDTI and accurately detected thrombi. It may, therefore, serve as a safe and convenient alternative for the diagnosis of DVT.

10.
Clin Appl Thromb Hemost ; 26: 1076029620921235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32320276

RESUMO

BACKGROUND: Magnetic resonance (MR) black-blood thrombus imaging (BTI) is an accurate diagnostic technique for detecting deep vein thrombosis (DVT) but to date there have been no studies comparing the diagnostic performance and consistency of this technique at different field strengths. In this study, we evaluated and compared the diagnostic performance of BTI for detecting DVT at 1.5 T and 3.0 T field strengths. METHODS: A total of 40 patients with DVT were enrolled in this study from November 2015 up to October 2018. All patients underwent BTI, a contrast-free T1-weighted MR imaging technique for detecting DVT, and contrast-enhanced MR venography (CE-MRV) at 1.5 T or 3.0 T field strengths. The MR data analyses used 1160 segments from the venous lumen of the 40 patients. The signal-to-noise ratio and contrast-to-noise ratio between thrombus and muscle/lumen were calculated to compare BTI at 1.5 T or 3.0 T to determine the image performance for thrombus detection at 1.5 T or 3.0 T. Two physicians blinded to the study evaluated all BTI images and calculated the overall sensitivity (SE), specificity (SP), positive predictive value (PPV) and negative predictive value (NPV), accuracy, and diagnostic consistency at 1.5 T and 3.0 T. These images and values were compared to control CE-MRV images that had been obtained by 2 senior physicians and used as reference standards. In addition, the reliability and consistency of diagnoses between observers were also evaluated. RESULTS: Two study-blind physicians reviewed all BTI images to diagnose thrombus and to determine SE, SP, PPV, NPV, and accuracy. There were no statistical differences in SE, SP, PPV, NPV, or accuracy between the 1.5 T and 3.0 T groups. CONCLUSIONS: Black-blood thrombus imaging has high SE, SP, and accuracy for DVT diagnosis both at 1.5 T and 3.0 T field strengths. This noninvasive diagnostic technique, which does not require the use of contrast agents, can be widely used in the clinical screening of DVT and follow-up after treatment.


Assuntos
Angiografia por Ressonância Magnética/métodos , Trombose Venosa/diagnóstico , Feminino , Humanos , Masculino
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-837828

RESUMO

Diabetes mellitus can result in many ocular complications, such as retinopathy, optic neuropathy, neovascular glaucoma and metabolic cataract, and plays an important role in causing blindness. In addition to diabetic retinopathy, the incidence of diabetic ocular surface diseases is also increased. Diabetes can lead to changes in the ocular surface including the lacrimal glands, tarsal glands, conjunctiva, tear film and cornea, such as dry eye, meibomian gland dysfunction, and corneal epithelial damage. This article reviews the research progress of ocular surface lesions and the pathogenesis in type 2 diabetes mellitus, hoping to provide theoretical basis for its clinical diagnosis and treatment.

12.
Int J Ophthalmol ; 12(4): 621-626, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024817

RESUMO

AIM: To report the visual outcomes and refractive status in premature infants with and without retinopathy of prematurity (ROP) who were or not treated. METHODS: The clinical records of all premature infants with or without ROP and with or without treatment between 2007 and 2017 were retrospectively reviewed. Basic demographic data, serial changes in ROP incidence, treatment and outcomes, and the refractive states were analyzed. Correlations among myopia and astigmatism progression, birth weight, gestational age, and treatment methods were also analyzed. RESULTS: A total of 562 screened premature infants (all Chinese, 1124 eyes), were recruited with a 378:184 male-to-female ratio. Birth weight did not directly influence ROP incidence. The overall ROP incidence was 16.55% (93/562 cases). The incidences in boys and girls were 16.14% (33/378 cases) and 17.39% (32/184 cases), respectively, and this difference was not significant. However, all infants with serious ROP (stage IV and V) were male. Myopia combined with astigmatism was common in premature infants with and without ROP (30.99%, 172/555 cases), and myopic refraction (including myopia and myopia combined with astigmatism) was more common in premature infants with ROP (48.84%, 42/86 cases). In the >8.00 diopter group, there were significantly more ROP infants than without ROP. Myopic refraction (including myopia and myopia combined with astigmatism) was most common in infants with ROP after treatment (63.63%, 7/11 cases). CONCLUSION: The refractive state is different between premature infants and mature infants. Those treated for ROP had a higher chance of developing myopia, astigmatism, and higher diopter.

13.
J Investig Med ; 65(5): 899-911, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28330835

RESUMO

Telemedicine interventions may be associated with reductions in hospital admission rate and mortality in patients with heart failure (HF). The present study is an updated analysis (as of June 30, 2016) of randomized controlled trials, where patients with HF underwent telemedicine care or the usual standard care. Data were extracted from 39 eligible studies for all-cause and HF-related hospital admission rate, length of stay, and mortality. The overall all-cause mortality (pooled OR=0.80, 95% CI 0.71 to 0.91, p<0.001), HF-related admission rate (pooled OR=0.63, 95% CI 0.53 to 0.76, p<0.001), and HF-related length of stay (pooled standardized difference in means=-0.37, 95% CI -0.72 to -0.02, p=0.041) were significantly lower in the telemedicine group (teletransmission and telephone-supported care), as compared with the control group. In subgroup analysis, all-cause mortality (pooled OR=0.69, 95% CI 0.56 to 0.86, p=0.001), HF-related admission rate (OR=0.61, 95% CI 0.42 to 0.88, p=0.008), HF-related length of stay (pooled standardized difference in means=-0.96, 95% CI -1.88 to -0.05, p=0.039) and HF-related mortality (OR=0.68, 95% CI 0.54 to 0.85, p=0.001) were significantly lower in the teletransmission group, as opposed to the standard care group, whereas only HF-related admission rate (OR=0.64, 95% CI 0.52 to 0.79, p<0.001) was lower in the telephone-supported care group. Overall, telemedicine was shown to be beneficial, with home-based teletransmission effectively reducing all-cause mortality and HF-related hospital admission, length of stay and mortality in patients with HF.


Assuntos
Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/terapia , Telemedicina/métodos , Estudos de Casos e Controles , Doença Crônica , Hospitalização , Humanos , Tempo de Internação , Avaliação de Resultados em Cuidados de Saúde , Admissão do Paciente , Readmissão do Paciente , Qualidade de Vida , Resultado do Tratamento
14.
Chronobiol Int ; 34(3): 411-425, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28128993

RESUMO

We investigated whether human semen parameters present circannual rhythm or not, and whether environmental factors exert on semen quality. This retrospective study used data of patients mainly from Reproductive Medicine Center and Urology and Andrology Clinic of a general hospital in China. Sperm concentration and motility were measured by computer aided sperm analysis (CASA). Sperm morphology was scored based on the strict criteria (WHO, 2010). The Kruskal-Wallis rank test was used to investigate the relationship between semen parameters and season/month. Partial correlation coefficients were used to analyze the relationship between semen parameters and environmental factors. In this study, we found that sperm concentration and total amount per ejaculate were significantly lower in summer and higher in winter. But, sperm progressive motility and motility were significantly higher in spring and summer (from March to June), lower in autumn and winter (September and October). Unexpectedly, normal sperm morphology and mixed agglutination reaction (MAR) positive rate didn't vary along with season or month. Furthermore, temperature was negatively related to sperm concentration and total amount per ejaculate. Precipitation was positively associated with progressive motility and normal sperm morphology, but negatively related to sperm head defect percentage. The length of sunlight was positively related to progressive motility. The Air Quality Index (AQI) was positively associated with semen volume and sperm total amount per ejaculate. These suggest seasonal and monthly variation underlying some semen parameters.


Assuntos
Ritmo Circadiano/fisiologia , Sêmen/citologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/citologia , Adulto , China , Humanos , Masculino , Estudos Retrospectivos , Análise do Sêmen/métodos , Contagem de Espermatozoides/métodos , Temperatura
15.
Life Sci ; 167: 12-21, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27746188

RESUMO

AIMS: Adverse cardiovascular effects induced by peroxisome proliferator activator receptor-γ (PPAR-γ) activation were observed in clinical setting. But the underlying mechanism is unclear. Now, transgenic mice with cardiac specific peroxisome proliferator activator receptor-γ overexpression (TG-PPAR-γ) were used to explore the possible mechanisms. MATERIALS AND METHODS: Cardiac tissues from TG-PPAR-γ mice, a PPAR-γ over-expressing human cardiomyocyte line AC16 cell, and PPAR-γ agonist-treated primary cardiomyocytes were used to evaluate the expression of cardiac calcium regulatory proteins as sarcoplasmic reticulum Ca2+ ATPase, Na+/Ca2+ exchanger 1, ryanodine receptor 2 and phospholamban. Intracellular Ca2+ levels were also examined by flow cytometry and confocal microscopy with Fluo-4/AM in these cells. KEY FINDINGS: In this study, frequent ventricular premature contraction and polymorphic ventricular tachycardia were observed in TG-PPAR-γ but not in wild-type mice. Besides, we found the calcium regulatory proteins expression were higher in the TG-PPAR-γ mice, PPAR-γ overexpressing human cardiomyocyte line AC16 cell and PPAR-γ agonist-treated primary cardiomyocytes than the control group respectively. In addition, an increase of intracellular calcium levels and CaMKII δ expression in PPAR-γ overexpression and PPAR-γ activation group. Moreover, Inhibition of CaMKII δ could improve the intracellular calcium levels and reduce the occurrence of ventricular arrhythmia. SIGNIFICANCE: PPAR-γ over-expression perturbs the intracellular calcium homeostasis in cardiomyocytes which contribute to the ventricular arrhythmias and cardiac sudden death in TG-PPAR-γ mice.


Assuntos
Arritmias Cardíacas/genética , Cálcio/metabolismo , Ventrículos do Coração/patologia , Miócitos Cardíacos/patologia , PPAR gama/genética , Regulação para Cima , Animais , Arritmias Cardíacas/patologia , Arritmias Cardíacas/fisiopatologia , ATPases Transportadoras de Cálcio/genética , Linhagem Celular , Células Cultivadas , Regulação da Expressão Gênica , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Homeostase , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Miócitos Cardíacos/metabolismo
16.
Zygote ; 24(2): 293-300, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26081351

RESUMO

This study was conducted to determine the effects of l-carnitine (LC), as an antioxidant, in preventing spermatozoa damage during the freezing-thawing process in both astheno- and normozoospermic human semen samples. Seventy semen samples (37 asthenozoospermic and 33 normozoospermic) were involved in this study. Cryopreservation medium supplemented with 1.0 g/l LC was mixed with semen at a ratio of 1:1 (v/v). Controls were cryopreserved with freezing medium only. Assessment of motility, viability (VIA), mitochondrial membrane potential (MMP) and DNA fragmentation index (DFI) were performed on aliquots of fresh semen, frozen-thawed control and frozen-thawed LC treated samples. Supplementation of the cryopreservation medium with LC induced a significant improvement in post-thaw sperm parameters in both the asthenozoospermic and normozoospermic semen samples, compared with those of the control, regarding sperm fast forward motility, forward motility, total motility and VIA. LC showed better protective effects towards asthenozoospermia for DFI (F = 115.85, P < 0.01) and VIA (F = 67.14, P < 0.01) than did normozoospermic semen samples. We conclude that supplementation with LC prior to the cryopreservation process reduced spermatozoa cryodamage in both asthenozoospermic and normozoospermic semen samples. LC had better protective effects for asthenozoospermic human semen samples. Future research should focus on the molecular mechanism for and the different protective effects of LC between asthenozoospermic and normozoospermic semen samples during cryopreservation.


Assuntos
Astenozoospermia/fisiopatologia , Carnitina/farmacologia , Criopreservação/métodos , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Reprodutibilidade dos Testes , Sêmen/citologia , Sêmen/efeitos dos fármacos , Sêmen/metabolismo
17.
Zhongguo Zhong Yao Za Zhi ; 39(16): 3018-22, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25509280

RESUMO

The herbs used as the material for traditional Chinese medicine are mostly planted at mountain areas where there is appropriate weather condition. Due to the complex terrain condition in mountain area, the planting at such places is always associated with a scattered pattern, which inevitably bring difficulty to the work of accurate measurement for the planting area. Advanced research about monitoring the planting area for medicine-herb under complex environmental condition is so critical and meaningful for developing the medicine-herb planting to a large scale and an industry. Therefore, this research, taking the planting of Herpetospermum pedunculosum in Luding county as an example, utilizes RS&GIS: using the image data from TM and ETM datum as the remote sensing information source, integrating GPS data from quadrat survey on the spots, and analyzing on a GIS platform, to extract the planting area of H. pedunculosum in Luding county. The results indicate that: (1) the method and technology used to estimate the planting area of H. pedunculosum are feasible and can be applied to monitoring the planting area of medicine-herb at mountain area under complex environmental conditions: (2) the planting area of H. pedunculosum in Luding county is estimated to be 857. 246 acres by the methods utilized in this research, which is closed to the value from local statistical data with an error range less than 5%; (3) in consideration of those inevitable errorrs generating from the procedures such as remote sensing data acquisition, data preprocessing, data interpretation, and so on, and the fact that the classification of remote sensing data, which must be implemented by those above procedures, was used directly to extract the herb type, the accuracy of area estimation for the herb is significantly influenced by the accuracy of classification for herb type, and the estimated area is inevitably associated with some error.


Assuntos
Cucurbitaceae/química , Cucurbitaceae/crescimento & desenvolvimento , Sistemas de Informação Geográfica , Tecnologia de Sensoriamento Remoto/métodos , China , Medicina Tradicional Tibetana
18.
Naunyn Schmiedebergs Arch Pharmacol ; 387(11): 1037-44, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25064464

RESUMO

This study investigated the effects of fosinopril on the electrophysiological characteristics of the left ventricular hypertrophic myocardium in spontaneously hypertensive rats (SHRs). Twenty-four 10-week-old male SHRs were divided into fosinopril and non-fosinopril groups (n = 12 each). Twelve 10-week-old Wistar-Kyoto rats were used a control group. Left ventricular mass index and ventricular fibrillation threshold (VFT) were measured after 8 weeks of fosinopril or saline treatment. L-type calcium current (I CaL), sodium current (I Na), and transient outward potassium current (I to) were measured in left ventricular myocytes after 8 weeks of fosinopril or saline treatment using the whole-cell patch-clamp technique. VFT was higher in the fosinopril group than in the non-fosinopril group (17.5 ± 1.2 mA vs. 15.6 ± 1.1 mA, P < 0.01). The density of I CaL was lower in the fosinopril group than in the non-fosinopril group (-7.17 ± 0.13 pA/pF vs. -7.87 ± 0.13 pA/pF, P < 0.05). The density of I to was higher in the fosinopril group than in the non-fosinopril group (14.46 ± 0.28 pA/pF vs. 12.66 ± 0.25 pA/pF, P < 0.05). I to was positively correlated with VFT (r = 0.90, P < 0.001) and was found to be associated independently with VFT (P < 0.001). Fosinopril improves the electrophysiological characteristics of the left ventricular hypertrophic myocardium in SHRs.


Assuntos
Anti-Hipertensivos/farmacologia , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Fosinopril/farmacologia , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Animais , Canais de Cálcio Tipo L/metabolismo , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Técnicas de Patch-Clamp , Canais de Potássio/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Canais de Sódio/metabolismo
19.
Hypertens Res ; 37(9): 824-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24758867

RESUMO

The objective was to investigate the effects of valsartan on the electrophysiological characteristics of left ventricular hypertrophic myocardium in spontaneously hypertensive rats (SHR). A total of 24 10-week-old male SHR were divided into two groups: valsartan and non-valsartan groups (n=12 in each). Twelve 10-week-old Wistar-Kyoto rats were served as the control group. Kv4.2 expression was measured in left ventricular myocardium using western blots. In addition, the systolic blood pressure, left ventricular mass index (LVMI), ventricular effective refractory period and ventricular fibrillation threshold (VFT) were also measured after eight weeks. INa, ICaL, Ito and membrane capacitance were measured in left ventricular myocytes after 8 weeks by whole-cell patch clamp. Valsartan decreased LVMI compared with the non-Valsartan group (Valsartan vs. non-Valsartan: 3.2±0.03 mg g(-1) vs. 3.7±0.02 mg g(-1), P<0.01). Valsartan also enhanced the VFT compared with the non-Valsartan group (Valsartan vs. non-Valsartan: 18.6±0.3 mA vs. 15.4±0.4 mA, P<0.01). The expression of Kv4.2 was significantly lower in the non-Valsartan and Valsartan groups compared with the control group (P<0.01). The expression of Kv4.2 was significantly higher in the Valsartan group compared with the non-Valsartan group (P<0.01). Valsartan decreased the density of ICaL compared with non-Valsartan group (Valsartan vs. non-Valsartan: -5.5±0.6 pA/pF vs. -7.2±0.9 pA/pF, P<0.05). Valsartan improved the density of Ito compared with non-Valsartan group(Valsartan vs. non-Valsartan: 13.93±0.8 pA/pF vs. 11.22±1.0 pA/pF, P<0.05). Valsartan improves the electrophysiological characteristics of left ventricular hypertrophic myocardium in spontaneously hypertensive rat.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Hipertrofia Ventricular Esquerda/fisiopatologia , Miocárdio/metabolismo , Tetrazóis/farmacologia , Valina/análogos & derivados , Animais , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Hipertrofia Ventricular Esquerda/metabolismo , Masculino , Ratos , Ratos Endogâmicos SHR , Canais de Potássio Shal/metabolismo , Valina/farmacologia , Valsartana
20.
Naunyn Schmiedebergs Arch Pharmacol ; 387(5): 419-25, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24441766

RESUMO

To investigate fosinopril's effect on the transient outward potassium current (Ito) of differing degrees of hypertrophied myocytes in the spontaneously hypertensive rat (SHR). Ten- and 24-week-old SHRs were used as models for cardiac hypertrophy. Hypertrophied ventricular myocytes were exposed to 1, 10, and 100 µmol/L fosinopril; the whole-cell patch-clamp technique was used to study the effects on the transient outward potassium current. Ito current density was decreased in SHR myocytes relative to controls (14.17 ± 0.31 and 11.62 ± 0.08 pA/pF in 10- and 24-week-old SHR versus 16.73 ± 0.15 pA/pF, p < 0.01). Higher concentrations of fosinopril (10 and 100 µmol/L) increased Ito peak current density in 10-week-old SHR myocytes compared with controls (14.92 ± 0.14 and 15.27 ± 0.13 pA/pF versus 14.17 ± 0.31 pA/pF, p < 0.01). Fosinopril increased Ito peak current density in 24-week-old SHR myocytes at all doses (12.70 ± 0.07, 13.74 ± 0.10, and 14.53 ± 0.13 versus 11.62 ± 0.08 pA/pF for controls, p < 0.01). Fosinopril had a greater Ito elevation potential on hypertrophied myocytes in 24-week-old compared with 10-week-old SHR for each dose (1.08 ± 0.09 versus 0.37 ± 0.26 pA/pF, p < 0.01; 2.13 ± 0.05 versus 0.75 ± 0.35 pA/pF, p < 0.01; 2.92 ± 0.07 versus 1.10 ± 0.40 pA/pF, p < 0.01). Fosinopril increased Ito current density in hypertrophied myocytes. This effect was more pronounced in myocytes with a greater degree of hypertrophy.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Fosinopril/farmacologia , Hipertensão/metabolismo , Hipertrofia Ventricular Esquerda/metabolismo , Miocárdio/metabolismo , Canais de Potássio/efeitos dos fármacos , Animais , Hipertensão/tratamento farmacológico , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
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