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1.
Ying Yong Sheng Tai Xue Bao ; 34(10): 2644-2654, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-37897271

RESUMO

We examined the responses of physiological and leaf anatomic structural characteristics of six Helleborus orientalis cultivars to different degrees of drought stress. A membership function was used to evaluate drought resis-tance and identify physiological and leaf anatomical indicators that exhibited a stronger correlation with drought tolerance. The results showed that leaf thickness, leaf area per unit mass and soluble protein levels of the six cultivars significantly decreased with the increases of drought stress. Net photosynthetic rate, stomatal conductance, and transpiration rate of leaves increased first and then decreased, while the intercellular CO2 concentration decreased. The relative electrical conductivity, MDA, and H2O2 contents of leaves were increased. Soluble saccharide and proline contents, and antioxidant enzyme activities were first elevated and then decreased. With the increases of drought stress, the ratio of palisade tissue thickness to sponge tissue thickness and stomatal density increased. Key indicators and relativities in evaluating drought resistance of those cultivars were proline, soluble sugars, and the ratio of palisade tissue thickness to sponge tissue thickness. H. orientalis 'Anemone Red' and H. orientalis 'Ane-mone Red spotted' had better drought resistance, which could be the excellent parental materials for the cultivation of new drought-resistant cultivars in the future.


Assuntos
Secas , Helleborus , Resistência à Seca , Helleborus/metabolismo , Peróxido de Hidrogênio , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Antioxidantes/metabolismo , Prolina , Estresse Fisiológico , Água/fisiologia
2.
Ying Yong Sheng Tai Xue Bao ; 31(5): 1660-1672, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32530245

RESUMO

Research on the spatial quantitative evaluation of land use and ecosystem service value in the source region of the Yellow River is of great significance for ensuring the ecological security of the river basin. Taking Maduo County in the source region of the Yellow River as an example, based on a 3 km × 3 km grid unit, the spatial autocorrelation method was applied to construct an evaluation model of ecosystem service value. The spatial autocorrelation pattern characteristics of Maduo County in 2015 was quantitatively evaluated, and the spatial information of ecosystem service value was visually expressed. The results showed that, at the examined grid scale, the area of grasslands with different coverages was large, and water grid area accounted for 42.9% of the total grids and was mainly distributed in the northwest of Maduo County. The construction land showed a "line-like" distribution from northeast to southwest, while the unutilized land was more distributed in southwest and less in northeast. In space, different land use type grids interacted with each other, with positive correlation and cluster distribution. The values of global Moran I and local Moran I of water area was the largest, with strongest spatial aggregation and high local connectivity. The global Moran I and local Moran I values of the construction land were 0.293 and 0.127, respectively, with the weakest spatial autocorrelation and clustering characteristics in a small range. In 2015, ecosystem service value (ESV) of Maduo County was 93.887 billion yuan, the mean ESV across all the grids was 3.20×107 yuan, with a maximum of 19.96×107 yuan. The water distribution grid had high ESV. On the whole, the ESV distribution pattern in Maduo County had a significant spatial positive correlation, with clustered ESV grids. The ESV grids of different land use types generally showed high-high cluster and low-low cluster, with the spatial pattern of high-low cluster and low-high cluster being sporadic. We proposed several possible strategies of land space planning and use control. First, the water and unused land should adopt a "centralized continuum" protection mode that emphasize the value of ecological spillovers. Second, grasslands with different coverage levels should adopt a "group-type" eco-governance model of primary and secondary division and zoning management. Third, construction land should adopt a small-scale intensive development and utilization model in a "corridor " distribution pattern.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Rios , Análise Espacial
3.
J Cell Biochem ; 120(3): 4675-4686, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30520140

RESUMO

Polycystic ovary syndrome (PCOS), known as a common endocrine disorder among females, plagues many PCOS patients. The current study aimed to explore the correlations of sex hormone-binding globulin (SHBG) polymorphisms with the outcome of in vitro fertilization-embryo transfer (IVF-ET) in PCOS patients. PCOS patients who underwent IVF-ET and patients with non-PCOS-related infertility were selected in the study. Correlations of SHBG rs6259 and rs727428 with the risk factors in PCOS were analyzed, followed by the evaluation of the effect of SHBG polymorphisms on the outcome of IVF-ET in PCOS patients. At last, unconditional logistic regression analysis was performed to study the risk factors for IVF-ET treatment outcome. Compared with SHBG rs6259 GG carriers, the incidence of PCOS was found to be elevated in SHBG rs6259 GA+AA carriers which indicated that the A allele was a risk factor for PCOS. Compared with SHBG rs6259 TT carriers, the number of retrieved oocytes and embryo as well as the fertility rate in SHBG rs6259 GA+AA carriers was found to be decreased, while the abortion rate, incidence of ovarian hyperstimulation syndrome, transplant rejection rate, estradiol, and testosterone in serum, as well as testosterone in follicular fluid were elevated. The luteal hormone, serum testosterone, and progesterone and GA+AA genotype of rs6259 were the risk factors for IVF-ET treatment outcome. Taken together, the study showed that SHBG rs6259 polymorphisms might be correlated with the risk of PCOS and the outcome of IVF-ET treatment.


Assuntos
Alelos , Transferência Embrionária , Fertilização In Vitro , Síndrome do Ovário Policístico/genética , Polimorfismo Genético , Globulina de Ligação a Hormônio Sexual/genética , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Síndrome do Ovário Policístico/epidemiologia , Síndrome do Ovário Policístico/metabolismo , Fatores de Risco , Globulina de Ligação a Hormônio Sexual/metabolismo
4.
Am J Physiol Cell Physiol ; 315(2): C225-C235, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29719173

RESUMO

Some microRNAs (miRs) are dysregulated in cancers, and aberrant miR expression has been reported to correlate with chemoresistance of cancer cells. Therefore, the present study aims at investigating the effects of microRNA-139-5p (miR-139-5p) on cisplatin resistance of ovarian cancer (OC) with involvement of ring finger protein 2 (RNF2) and the mitogen-activated protein kinase (MAPK) signaling pathway. OC tissues were obtained from 66 primary OC patients. The cisplatin-sensitive A2780 and cisplatin-resistant A2780/DDP cell lines were collected for construction of RNF2 silencing and overexpressed plasmids. Cell vitality and apoptosis were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and annexin V-FITC/propidium iodide double-staining, respectively. Next, expression of RNF2, extracellular signal-related kinase, and p38 was determined by quantitative reverse transcription-quantitative polymerase chain reaction and Western blot analysis. Finally, the volume of xenograft tumors in BALB/c nude mice was detected. RNF2 and miR-139-5p were identified to be involved in OC. In addition, MAPK activation and RNF2 were related to cisplatin resistance of OC. miR-139-5p was downregulated in cisplatin-resistant OC tissues, and miR-139-5p overexpression could inhibit cell vitality, reduce cisplatin resistance, and promote apoptosis of OC cells. Furthermore, miR-139-5p combined with MAPK inhibitors more obviously reduced cisplatin resistance of OC. Taken together, this study demonstrated that miR-139-5p overexpression combined with inactivation of the MAPK signaling pathway can reverse the cisplatin resistance of OC by suppressing RNF2. Thus, miR-139-5p overexpression might be a future therapeutic strategy for OC.


Assuntos
Cisplatino/farmacologia , Regulação para Baixo/genética , Resistencia a Medicamentos Antineoplásicos/genética , Sistema de Sinalização das MAP Quinases/genética , MicroRNAs/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Animais , Apoptose/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Complexo Repressor Polycomb 1 , Transdução de Sinais/genética
5.
J Cell Physiol ; 233(9): 7379-7390, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29575013

RESUMO

Cervical cancer (CC) remains a highly prevalent cancer and mortality globally among women globally. The aim of the present study was to assess the ability of miR-374b to regulate CC cells through JAM-2, whilst exploring whether the underlying mechanism and its relation to the p38/ERK signaling pathway. During the study, microRNA-374b (miR-374b) was observed to have been expressed at a low level among CC tissues. Hence, a series of miR-374b mimics, miR-374b inhibitors, siRNA against JAM-2, SB202190 (an inhibitor for p38), and PD98059 (an inhibitor for ERK) were introduced to treat CC Siha cells and normal cervical Ect1/E6E7 cells. MTT, flow cytometry, scratch test, and transwell assays were applied to determine cell viability, apoptosis, migration, and invasion. The inhibitory role of the p38/ERK signaling pathway was observed in the CC cells treated with miR-374b mimics or siRNA against JAM-2. miR-374b mimic exposure was found to reduce cell viability, migration, and invasion, but induce apoptosis. MiR-374b inhibitor exposure was observed to have induced effects on the CC cells in a contrary manner to those induced by that of the miR-374b mimics. The key findings of the study demonstrated that miR-374b significantly inhibits cell proliferation, migration, and invasion through the blockade of the p38/ERK signaling pathway activation, as well as negatively binding to JAM-2, highlighting its potential as a therapeutic target for CC.


Assuntos
Apoptose/genética , Moléculas de Adesão Celular/metabolismo , Sistema de Sinalização das MAP Quinases , MicroRNAs/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Adulto , Sequência de Bases , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Regulação para Cima/genética
6.
Chin Med J (Engl) ; 125(14): 2610-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22882948

RESUMO

OBJECTIVE: To discuss the present status and progress of clinical research on the cognitive effects caused by different types of brain tumors and common treatments. DATA SOURCES: The data used in this review were mainly from PubMed articles published in English from 1990 to Febuary 2012. Research terms were "cognitive deficits" or "cognitive dysfunction". STUDY SELECTION: Articals including any information about brain tumor related cognitive deficits were selected. RESULTS: It is widely accepted that brain tumors and related treatments can impair cognitive function across many domains, and can impact on patients' quality of life. Tumor localization, lateralization, surgery, drugs, radiotherapy and chemotherapy are all thought to be important factors in this process. However, some conflicting findings regarding brain tumor-related cognitive deficits have been reported. It can be difficult to determine the mechanism of these treatments, such as chemotherapy, antibiotics, antiepileptics, and steroids. Future research is needed to clarify these potential treatment effects. CONCLUSIONS: Cognitive function is important for patients with brain tumor. Much more focus has been paid on this field. It should be regarded as an important prognostic index for the patients with brain tumor, and neuropsychological tests should be used in regular examinations.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Cognição/fisiologia , Glioma/fisiopatologia , Humanos
7.
Zhonghua Yi Xue Za Zhi ; 90(5): 301-4, 2010 Feb 02.
Artigo em Chinês | MEDLINE | ID: mdl-20368049

RESUMO

OBJECTIVE: To analyze the effects of intracranial tumors and tumor resection on patients' memory functions. METHODS: Four different memory scales were employed to evaluate 58 intracranial tumor patients' memory functions including short-term memory, delayed memory, clue memory and long-term memory. Thirty-five patients received postoperative follow-ups. There were also 18 healthy controls. RESULTS: The extra-cerebral tumor patients presented with delayed memory and long-term memory disorders while intra-cerebral tumor patients suffered from short-term, delayed and severe long-term memory disorders. Patients with dominant hemispheric tumors had more serious memory disorders in all types. Scores obtained after surgery showed an aggravated long-term memory disorder. Sellar region tumors and transsphenoidal tumor resection had no effects upon memory functions. CONCLUSION: Intracranial tumors cause memory disorders. Tumors with different locations and characters have different memory impairments. Intra-cerebral tumors result in more severe memory impairment than extra-cerebral tumors. And dominant hemispheric tumors are worse than non-dominant hemispheric tumors. Tumor resection decreases long-term memory functions.


Assuntos
Neoplasias Encefálicas/psicologia , Transtornos da Memória/etiologia , Complicações Pós-Operatórias/etiologia , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/cirurgia , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 27(4): 293-7, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16875529

RESUMO

OBJECTIVE: To study the rate of human immunodeficiency virus (HIV) seroconversion, HIV transmission and related risk factors among injecting drug users (IDUs) in an area of Sichuan province. METHODS: In November 2002, a community-based baseline survey was conducted to recruit 333 HIV-seronegative IDUs for a prospective cohort study in Xichang county of Sichuan province, China. Follow-up visits were carried out every 6 months to study the situation of drug use, sexual behaviors of the IDUs and blood specimens were collected to test for antibodies against HIV and syphilis. RESULTS: During a 24-month follow-up period, cohort retention rate and HIV incidence were 75.7% and 2.53 per 100 person-years [95% confidence interval (CI): 1.10-3.97)], respectively. Multivariate Poisson regression model showed that risk factors which were significantly associated with HIV seroconversion would include: ethnicity (RR = 12.42; 95% CI: 2.72-56.74, P = 0.0012) and needle or syringe sharing in the past 3 months (RR = 4.06; 95% CI: 1.29-12.81, P = 0.0168). Syphilis seroconversion in this cohort was 4.71 per 100 person-years (95% CI: 2.59-6.82). In multivariate Poisson regression being female (RR = 4.42; 95% CI: 1.78-10.99, P = 0.0014) appeared to be the only factor which was significantly associated with syphilis seroconversion. CONCLUSION: Our study results showed that there was a rapid transmission of HIV and syphilis among IDUs in Sichuan province, suggesting that effective intervention should be urgently taken.


Assuntos
Soropositividade para HIV/imunologia , Abuso de Substâncias por Via Intravenosa , Sífilis/imunologia , Estudos de Coortes , Soropositividade para HIV/transmissão , Humanos , Estudos Prospectivos , Fatores de Risco , Comportamento Sexual , Sífilis/transmissão
10.
Chin Med J (Engl) ; 119(23): 1941-8, 2006 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-17199937

RESUMO

BACKGROUND: Unregulated commercial blood/plasma collection among farmers occurred between 1992 and 1995 in central China and caused the second major epidemic of human immunodeficiency virus type 1 (HIV-1) infection in China. It is important to characterize HIV-1-infected former blood donors and to study characteristics associated with disease progression for future clinical intervention and vaccine development. METHODS: A cross-sectional study was performed on HIV-1-infected former blood donors (FBDs) and age-matched HIV-seronegative local residents. Demographic, epidemiologic, clinical and key laboratory data were collected from all study participants. Both unadjusted and adjusted multivariate linear regressions were employed to analyze the association of the decrease of CD4(+) T-cell counts with other characteristics. RESULTS: Two hundred and ninety-four HIV-1-infected FBDs and 59 age-matched HIV-seronegative local residents were enrolled in this study. The unregulated blood/plasma collection occurred more than a decade (10.8 - 12.8 years) ago, which caused the rapid spread of HIV-1 infection and the high prevalence of co-infection with hepatitis C virus (HCV, 89.5%); hepatitis B virus (HBV) co-infection was observed in only 11 HIV(+)participants (3.7%). Deterioration in both clinical manifestation and laboratory parameters and increase of viral loads were observed in parallel with the decrease of CD4(+) T-cell counts. The decrease of total lymphocyte counts (P < 0.001) and hemoglobin levels (P < 0.001) and the appearance of dermatosis (P = 0.03) were observed in parallel with the decrease of CD4(+) T-cell counts whereas viral loads (P < 0.001) and CD8(+) T-cell counts (P = 0.01) were inversely associated with CD4(+) T-cell counts. CONCLUSIONS: Co-infection with HCV but not HBV is highly prevalent among HIV-1-infected FBDs. CD4(+) T-cell counts is a reliable indicator for disease progression among FBDs. Total lymphocyte counts, hemoglobin level and appearance of dermatosis were positively associated with CD8(+) T-cell counts and viral loads were inversely associated with the decreased CD4(+) T-cell counts.


Assuntos
Doadores de Sangue , Infecções por HIV/epidemiologia , HIV-1 , Adulto , Idoso , China/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/imunologia , Hepatite C/complicações , Humanos , Masculino , Pessoa de Meia-Idade
11.
Zhonghua Liu Xing Bing Xue Za Zhi ; 27(11): 939-42, 2006 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-17402192

RESUMO

OBJECTIVE: To investigate the human immunodeficiency virus (HIV) and syphilis incidence rates as well as the retention rate in a cohort with 6-month follow-up study among female sex workers (FSWs). METHODS: From December, 2004, to January, 2005, a community-based baseline survey was conducted to recruit 343 FSWs for a prospective cohort study in Xichang county of Sichuan province, China. Follow-up visits were conducted at 6 months to analyze risk factors associated with cohort retention for subjects' baseline sociodemographic and sexual behavioral characteristics. Blood specimens were also collected to test antibodies against HIV and syphilis. RESULTS: During the 6-month follow-up period, HIV and syphilis incidence appeared to be 1.00 per 100 person-years and 6.23 per 100 person-years, respectively. The rate of retention in the cohort was 53.6% (184/343). Results from multivariate logistic regression model showed that factors were significantly associated with cohort retention including people with minority ethnic background (OR = 0.36; 95% CI: 0.18-0.74), people having participated in AIDS prevention program (OR = 1.83; 95% CI: 1.17-2.86) or being clients in the last 6 months > or = 50 (OR = 1.75; 95% CI: 1.11-2.77) and having changed living/working place (OR = 0.56; 95% CI: 0.33-0.94). CONCLUSION: The results of this study showed that the syphilis incidence and unprotected sex behavior were high among local FSWs. People belonged to Han nationality, having participated in AIDS prevention program and having a steady living/working place were associated with cohort retention at 6-month follow-up study among FSWs, respectively.


Assuntos
Infecções por HIV/epidemiologia , Trabalho Sexual , Sífilis/epidemiologia , China/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Fatores de Risco , Comportamento Sexual , Transtornos Relacionados ao Uso de Substâncias
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