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1.
Mol Ther Nucleic Acids ; 18: 518-532, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31671345

RESUMO

Long non-coding RNAs (lncRNAs) have been shown to be crucial regulators in numerous human diseases. However, little is known about their effects on early recurrent miscarriage (RM). Here we aimed to investigate the role of lncRNA EPB41L4A-AS1 on placental trophoblast cell metabolic reprogramming, which might be involved in the pathogenesis of RM. After microarray and GEO database analyses, we found that EPB41L4A-AS1 was significantly increased in early RM placental tissue, and this increase may relate to estradiol-mediated upregulation of PGC-1α. EPB41L4A-AS1 overexpression inhibits glycolysis but increases the dependence on fatty acid oxidation in mitochondrion metabolism and suppresses the Warburg effect, which is necessary for rapid growth of the placental villus, leading to miscarriage. Mechanistic analyses demonstrated that EPB41L4A-AS1 functions as a lncRNA in the regulation of VDAC1 and HIF-1α expression through enhancement of H3K4me3 levels in the promoters of VDAC1 and HIF1A-AS1, a natural antisense transcript (NAT) lncRNA of HIF-1α. Taken together, these findings demonstrate that aberrant expression of EPB41L4A-AS1 is involved in the etiology of early RM, and it may be a candidate diagnostic hallmark and a potential therapeutic target for early RM treatment.

2.
Mol Cell Probes ; 46: 101422, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31319160

RESUMO

The vast majority of first-trimester pregnancy losses are the consequence of numerical aberrations in fetal chromosomes, which may involve nearly all chromosomes. Although commercial probes for all chromosomes are available for multiplex ligation-dependent probe amplification (MLPA) and fluorescence in situ hybridization (FISH) analyses, their use has rarely been reported for screening all 24 chromosomes for early fetal demise, especially by FISH. Here, we validated the ability of MLPA and FISH techniques as two low-cost aneuploidy screening methods for 24 chromosomes in 165 chorionic villus samples (CVSs). The results obtained by two methods were compared by the Chi-square test and the Kappa agreement test. Both methods gave conclusive results for all CVSs tested and showed highly consistent results (kappa = 0.890, p < 0.001). There was no statistically significant difference between the aneuploidy rate of the CVSs tested by the two methods (p = 0.180). Most of the samples showed fully concordant molecular karyotyping results (81.21%) between the two analytical methods, 10.91% had incompletely concordant results, and 7.88% had discordant results. The inconsistencies included segmental abnormalities, mosaicism, and polyploidy. Both assays used to screen 24 chromosomes were powerful techniques for detecting aneuploidy in CVSs. In terms of cost-effectiveness and diagnostic accuracy, the combination of subtelomeric (P036, P070) and centromeric (P181) MLPA assays is the better analytic strategy and follow-up analysis by FISH is recommended for MLPA-negative samples.

3.
Sci Total Environ ; 688: 542-554, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31254820

RESUMO

Ground ice is a distinctive feature of permafrost, and its thawing under climate change can alter the regional hydrological and biogeochemical cycles. Spatial variations and determinants of ground ice isotopes are critical to understand subsurface water cycling during freeze-thaw process in the context of climate change, while they are not well known in permafrost region due to lack of field investigation. We examined spatial distributions and controlling factors of ground ice isotopes using data of 8 soil profiles surveyed in permafrost areas of the Qinghai-Tibet Plateau (QTP). The stable isotope values (δ2H and δ18O) of subsurface water on the QTP were higher than those in Arctic tundra ecosystem and East Siberian permafrost region. Isotopic values of water components differed each other, and varied significantly among the sampling sites. The spatial distribution of isotopes was complex. Isotopes generally decreased with depth within the soil profile, implying a general isotope depth gradient across different permafrost-affected areas. Water source, evaporative and freeze-out fractionation, and cryoturbation affect soil water isotopes. Correlation analyses showed that δ2H and δ18O in soil water positively related to air temperature and soil temperature, while negatively related to soil moisture, depth, active layer thickness, vegetation coverage, elevation, and precipitation. Elevation and soil depth mainly controlled spatial distributions of ground ice isotopes. The results could provide a new insight into soil moisture movement and cycling during freeze-thaw process in the permafrost region of the QTP, which is helpful to understand subsurface water cycle mechanism in the context of permafrost degradation.

4.
Sci Total Environ ; 661: 630-644, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30682613

RESUMO

Stable isotopic tracing has proven to be a useful tool for assessing surface water source dynamics and hydrological connectivity in permafrost regions. This study has investigated the contribution of precipitation to water within the active layer at three long-term observation sites, including Fenghuoshan (FHS), Hoh Xil (KKXL) and Wudaoliang (WDL), by using isotopic tracer technique and two-component mixing model. The results showed that precipitation was the predominant source for water within the active layer, permafrost and ground ice near permafrost table at the three sites. Precipitation in August was the predominant source for water within the active layer at FHS, and precipitation in September was the main source at KKXL and WDL. The variation of isotopic values at different levels indicated that the water sources within the active layer could vary as the depth increases. The evaporation fractionation of water within the active layer at WDL was noticeable at depths of 0-50 cm, and the evaporation intensity decrease gradually from late June to late September. The relationship of isotopic tracing values between precipitation and water within the active layer at depths of 0-50 cm becomes more significant as the amount of the recently-occurring precipitation increases. Moreover, the relatively higher d-excess in precipitation indicates that local recycled moisture has greater contribution to precipitation. The differences of d-excess in most water within the active layer, permafrost and ground ice near permafrost table revealed that there were isotopic fractionation when precipitation supplying to above-mentioned three water bodies. The precipitation event amounted to 8.1 mm at KKXL can exert 49% ±â€¯7.1% and 30.8% ±â€¯3.6% contribution to water within the active layer at depths of 0-10 cm and 10-20 cm, respectively. While the long-period contribution cannot be identified because of the impact of evaporation. The results would provide new insights into the contribution of precipitation to water within the active layer on the QTP, which is also helpful to improve process-based hydrological models in the permafrost regions.

5.
Sci Total Environ ; 650(Pt 1): 661-670, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30212695

RESUMO

The Qinghai-Tibet Plateau (QTP), where is underlain by the highest and most extensive mid-altitude permafrost, is undergoing more dramatic climatic warming than its surrounding regions. Mapping the distribution of permafrost is of great importance to assess the impacts of permafrost changes on the regional climate system. In this study, we applied logistic regression model (LRM) and multi-criteria analysis (MCA) methods to map the decadal permafrost distribution on the QTP and to assess permafrost dynamics from the 1980s to 2000s. The occurrence of permafrost and its impacting factors (i.e., climatic and topographic elements) were constructed from in-situ field investigation-derived permafrost distribution patterns in 4 selected study regions. The validation results indicate that both LRM and MCA could efficiently map the permafrost distribution on the QTP. The areas of permafrost simulated by LRM and MCA are 1.23 × 106 km2 and 1.20 × 106 km2, respectively, between 2008 and 2012. The LRM and MCA modeling results revealed that permafrost area has significantly decreased at a rate of 0.066 × 106 km2 decade-1 over the past 30 years, and the decrease of permafrost area is accelerating. The sensitivity test results indicated that LRM did well in identifying the spatial distribution of permafrost and seasonally frozen ground, and MCA did well in reflecting permafrost dynamics. More parameters such as vegetation, soil property, and soil moisture are suggested to be integrated into the models to enhance the performance of both models.

6.
J Assist Reprod Genet ; 35(8): 1437-1442, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29785531

RESUMO

OBJECTIVE: To evaluate the association of two common methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms with recurrent miscarriage (RM) and repeated implantation failure (RIF) METHODS: The study comprised of 521 patients, with a history of RM (n = 370) or RIF (n = 151). One hundred forty-four women with fallopian tube blockages who had successfully conceived after the first in vitro fertilization embryo transfer treatment served as the control group. The MTHFR alleles, genotypes, and haplotypes were assessed in different groups. RESULTS: There was no difference in allele frequency and distribution of MTHFR polymorphisms between case and control patients. The 1298AA genotype was represented in a higher frequency, and 1298AC genotype was significantly lower in subfertile group when compared to the control group. A significant relationship was found between the 1298AC genotype and the RIF subgroup. The haplotype 677CC/1298AA was overrepresented in the RM subgroup (> 2 times) and haplotype 677CC/1298AC was underrepresented in the RIF subgroup (P < 0.05). Nevertheless, these two haplotypes were not connected to fertilization and embryo cleavage rates. CONCLUSION: Our findings indicate that the MTHFR gene polymorphism might play a role in the etiology of patients with RM or RIF. No adverse effects of different MTHFR haplotypes on embryo development were detected. Further studies on the biological role are needed to better understand the susceptibility to pregnancy complications.


Assuntos
Aborto Habitual/genética , Implantação Tardia do Embrião/genética , Implantação do Embrião/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Aborto Habitual/fisiopatologia , Adulto , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Polimorfismo de Nucleotídeo Único , Gravidez
7.
Sci Total Environ ; 626: 366-376, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29353782

RESUMO

Ground ice is a distinctive feature of permafrost terrain. The vertical distribution and factors controlling the hydrochemistry of ground ice are important for studying soil moisture and salt migration during the freeze-thaw process in soil. These factors are also important components of hydrological cycles in cold regions. The hydrochemical characteristics of ground ice on the Qinghai-Tibetan Plateau (QTP) are not well known. We examined the characteristics of ground ice hydrochemistry using data from 9 soil profiles in permafrost regions of the central QTP. The isotopes and anion concentrations of subsurface water on the QTP were higher than those in Arctic polygonal ground regions. The spatial distribution of anions was complex. Well-developed hydrochemical depth gradients occurred within the soil profile. Isotopes decreased and anions increased with depth, suggesting general vertical patterns of soil hydrochemistry across different permafrost regions. Cl- and SO42- concentrations in soil water increased with depth, while NO3- concentration did not change with depth. Freeze-out fractionation, self-purification, and desalination greatly impact soil hydrochemistry. The major factors controlling variation of soil water chemistry were soil moisture, air temperature, and active layer thickness. The results could provide a framework for understanding ground ice origins and the moisture and salt migration pathways in the context of permafrost changes. This information could be useful in developing process-based permafrost hydrologic models.

8.
Clin Chim Acta ; 475: 78-84, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29037841

RESUMO

BACKGROUND: To investigate the etiology of X-linked hypohidrotic ectodermal dysplasia (XLHED) in a family with an inversion of the X chromosome [inv(X)(p21q13)] and to achieve a healthy birth following preimplantation genetic diagnosis (PGD). METHODS: Next generation sequencing (NGS) and Sanger sequencing analysis were carried out to define the inversion breakpoint. Multiple displacement amplification, amplification of breakpoint junction fragments, Sanger sequencing of exon 1 of ED1, haplotyping of informative short tandem repeat markers and gender determination were performed for PGD. RESULTS: NGS data of the proband sample revealed that the size of the possible inverted fragment was over 42Mb, spanning from position 26, 814, 206 to position 69, 231, 915 on the X chromosome. The breakpoints were confirmed by Sanger sequencing. A total of 5 blastocyst embryos underwent trophectoderm biopsy. Two embryos were diagnosed as carriers and three were unaffected. Two unaffected blastocysts were transferred and a singleton pregnancy was achieved. Following confirmation by prenatal diagnosis, a healthy baby was delivered. CONCLUSIONS: This is the first report of an XLHED family with inv(X). ED1 is disrupted by the X chromosome inversion in this XLHED family and embryos with the X chromosomal abnormality can be accurately identified by means of PGD.


Assuntos
Inversão Cromossômica , Cromossomos Humanos X/química , Displasia Ectodérmica Anidrótica Tipo 1/diagnóstico , Displasia Ectodérmica Anidrótica Tipo 1/prevenção & controle , Ectodisplasinas/genética , Diagnóstico Pré-Implantação/métodos , Adulto , Sequência de Bases , Blastocisto/citologia , Blastocisto/metabolismo , Pontos de Quebra do Cromossomo , Displasia Ectodérmica Anidrótica Tipo 1/genética , Displasia Ectodérmica Anidrótica Tipo 1/patologia , Implantação do Embrião , Éxons , Feminino , Fertilização In Vitro , Expressão Gênica , Marcadores Genéticos , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Recém-Nascido , Cariotipagem , Masculino , Repetições de Microssatélites , Linhagem , Gravidez
9.
Gene ; 636: 17-22, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28912064

RESUMO

Genetic defect is a major cause of early miscarriage, but still in many cases the etiology are not fully understood. Recent studies have shown that dysregulation of genes in placenta tissue are participated in the pathogenesis of unexplained early miscarriage. The aim of our study is to explore mRNA expression profile in placental chorionic villi and to reveal the underlying mechanism of unexplained early miscarriage. Chorionic villous were isolated and extracted from early miscarriage (n=3) and control pregnancy (n=3) placenta with normal chromosome karyotype using MLPA assay, and then mRNA expression profiles were determined by microarray. For verification the reproducibility of the microarray, three up-regulated genes and six down-regulated genes were chosen and examined by real-time PCR (n=30). A total of 81 genes were up-regulated and 231 genes were down-regulated when compared to the control group, and the differences were reached statistically significances (P<0.05). After Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, we found that almost down-regulation genes are associated with cell cycle and histone modification, and these genes are participated in several important physiological processes, such as cell proliferation, nuclear division, chromatic assembly, DNA packing and modification. These results indicated that cell cycle and histone modification genes, and related signaling pathway maybe contribute to the genesis and development of unexplained early miscarriage. Further studies and validations are necessary to elucidate the exact roles of these genes in miscarriage pathogenesis, which can develop tools for early detection and management.


Assuntos
Aborto Espontâneo/genética , Genes cdc , Código das Histonas/genética , Placenta/metabolismo , Aborto Espontâneo/metabolismo , Vilosidades Coriônicas/metabolismo , Feminino , Regulação da Expressão Gênica , Ontologia Genética , Humanos , Gravidez , Mapas de Interação de Proteínas , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
10.
Am J Reprod Immunol ; 78(2)2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28508475

RESUMO

CD8+ T cells are the main candidates to recognize and respond to fetal HLA-C at the fetal-maternal interface, but data on the amount of peripheral CD8+ T cells and their functions during the window of implantation in recurrent implantation failure (RIF) patients are limited. Peripheral blood was obtained from 56 women with RIF and 16 fertile women in the mid-luteal phase of the menstrual cycle, and the CD8+ T cells were determined by FACS analysis. No statistical differences in the proportion of peripheral CD8+ T cells were observed among the women with RIF and the control group. However, the levels of IFN-γ+ and TNF-α+ CD8+ T cells in the RIF group were significantly higher than those in the control group. The cytolytic activity and regulatory proportion of CD8+ T cells in RIF were similar to that in the control group. Our data indicated that the elevated expression levels of IFN-γ and TNF-α in peripheral CD8+ T cells may contribute to an impaired immune tolerance in women with RIF.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Implantação do Embrião/imunologia , Infertilidade Feminina/imunologia , Adulto , Feminino , Humanos , Tolerância Imunológica , Interferon gama/imunologia , Fator de Necrose Tumoral alfa/imunologia
11.
Int J Gynaecol Obstet ; 136(3): 304-308, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28099679

RESUMO

OBJECTIVE: To evaluate the pregnancy outcomes of couples containing a carrier of a reciprocal chromosome translocation (RCT) after assisted reproductive technology without preimplantation genetic diagnosis. METHODS: A retrospective study was performed using data for couples with an RCT carrier and control couples with a normal karyotype (1:4 ratio) who underwent assisted reproductive technology cycles at a Chinese fertility center in 2010-2011. The embryos were fertilized via in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Only the first pick-up cycles were used for analysis. Clinical variables were compared. RESULTS: Compared with the control group (n=164), the RCT group (n=41) had a marginally lower clinical pregnancy rate (46.3% [19/41] vs 54.3% [89/164]), implantation rate (21.7% [23/106] vs 26.9% [118/438]), multiple-gestation pregnancy rate (21.1% [4/19] vs 32.6% [29/89]), and delivery rate (36.6% [15/41] vs 47.6% [78/164]), whereas the spontaneous abortion rate was slightly higher (21.1% [4/19] vs 12.4% [11/89]). However, none of these differences were significant. CONCLUSION: The clinical outcomes for RCT carriers were acceptable after IVF/ICSI without performing preimplantation genetic diagnosis, indicating that this approach might comprise a feasible alternative fertility treatment for RCT carriers.


Assuntos
Aborto Espontâneo/epidemiologia , Infertilidade/terapia , Gravidez Múltipla/estatística & dados numéricos , Injeções de Esperma Intracitoplásmicas , Translocação Genética , Adulto , China , Feminino , Heterozigoto , Humanos , Recém-Nascido , Nascimento Vivo , Masculino , Gravidez , Taxa de Gravidez , Diagnóstico Pré-Implantação , Estudos Retrospectivos
12.
Reprod Health ; 14(1): 5, 2017 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086915

RESUMO

BACKGROUND: Chlamydia, caused by the bacterium Chlamydia trachomatis(C. trachomatis), is the most common sexually transmitted disease. The incidence is not clear due to the asymptomatic nature of early stage of infections. The incidence of Chlamydia has not been fully investigated in the Chinese Han population. Since chronic infection with can C. trachomatis can lead to infertility in males and females, it is important to determine the impact of infection on clinical outcomes. The aim of this study is to explore the epidemiology of C. trachomatis in subfertile couples and to determine whether infections will adversely affect clinical outcomes after assisted reproduction technique (ART) treatment. METHODS: Subfertile patients (n = 30760) were screened in the research for C. trachomatis in our center from January 2010 to December 2014. C. trachomatis-specific DNA was detected by Taq-man PCR from semen or swabs from the urethral, endocervix or vaginal. The control group consisted of 1140 subfertile patients without C. trachomatis infection. The prevalence and characteristics of C. trachomatis were identified for subfertile couples and clinical outcomes were collected and analyzed. A retrospective study was performed. RESULTS: Nine hundred and seventy patients were diagnosed with C. trachomatis infection, and the overall prevalence was 3.15% in the most recent five years, with a yearly increasing. The incidence was a higher in the second half of the year (3.40%) compared to the first half (2.69%). The age group with the highest-risk of infection with C. trachomatis was between 26 to 35 years old, and in about one third of the couples, both partners were infected. The basic parameters and clinical outcomes were not statistically significant between different the groups (P > 0.05), even though some minor data were different (P < 0.05). CONCLUSIONS: C. trachomatis is a common infection in subfertile people and it is essential to test for this organism in ART couples' screening. This study identified no adverse on clinical outcomes after successful treatment of C. trachomatis infection, regardless of gender, age and number of C. trachomatis copies.


Assuntos
Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis/isolamento & purificação , Infertilidade Feminina/epidemiologia , Infertilidade Masculina/epidemiologia , Adulto , China/epidemiologia , Infecções por Chlamydia/microbiologia , Feminino , Humanos , Infertilidade Feminina/microbiologia , Infertilidade Masculina/microbiologia , Masculino , Prevalência , Estudos Retrospectivos , Parceiros Sexuais , Adulto Jovem
13.
PLoS One ; 12(1): e0169732, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28068392

RESUMO

The Qinghai-Tibetan Plateau (QTP) contains the largest permafrost area in a high-altitude region in the world, and the unique hydrothermal environments of the active layers in this region have an important impact on vegetation growth. Geographical locations present different climatic conditions, and in combination with the permafrost environments, these conditions comprehensively affect the local vegetation activity. Therefore, the responses of vegetation to climate change in the permafrost region of the QTP may be varied differently by geographical location and vegetation condition. In this study, using the latest Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI) product based on turning points (TPs), which were calculated using a piecewise linear model, 9 areas within the permafrost region of the QTP were selected to investigate the effect of geographical location and vegetation type on vegetation growth from 1982 to 2012. The following 4 vegetation types were observed in the 9 selected study areas: alpine swamp meadow, alpine meadow, alpine steppe and alpine desert. The research results show that, in these study areas, TPs mainly appeared in 2000 and 2001, and almost 55.1% and 35.0% of the TPs were located in 2000 and 2001. The global standardized precipitation evapotranspiration index (SPEI) and 7 meteorological variables were selected to analyze their correlations with NDVI. We found that the main correlative variables to vegetation productivity in study areas from 1982 to 2012 were precipitation, surface downward long-wave radiation and temperature. Furthermore, NDVI changes exhibited by different vegetation types within the same study area followed similar trends. The results show that regional effects rather than vegetation type had a larger impact on changes in vegetation growth in the permafrost regions of the QTP, indicating that climatic factors had a larger impact in the permafrost regions than the environmental factors (including permafrost) related to the underlying surface conditions.


Assuntos
Altitude , Ecossistema , Monitoramento Ambiental , Pergelissolo , Algoritmos , China , Meio Ambiente , Geografia , Modelos Teóricos
14.
Mol Cytogenet ; 9: 79, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27752285

RESUMO

BACKGROUND: Spontaneous abortion (SA) is the most common complication of pregnancy, and chromosome aberrations are the principal cause of the first trimester abortuses in natural conception (NC) The increasing use of assisted reproductive technology (ART) has raised concern about chromosome abnormalities in ART-initiated pregnancies. Up to date, the literature on the risk of aneuploidy in failed pregnancies among various ART factors remain limited and inconclusive. This study aimed to explore the genetic etiology of pregnancy loss conceived from varying ART procedures. RESULTS: A total of 560 cases of villus that were successfully collected and performed molecular karyotype analysis were enrolled in present research, including 92 cases of NC, 340 cases of in-vitro fertilization (IVF) and 128 cases of intracytoplasmic sperm injection (ICSI). There was no statistical difference in the distribution of karyotyping results and the aneuploidy rate of each individual chromosome among NC, IVF and ICSI group. Both the total chromosomal abnormality rate and the one chromosome aneuploidy rate were increased with maternal age. Compared with fresh ET abortion group, frozen-thawed embryo transfer (FET) abortion group had elder maternal age (34.68 ± 4.73 years vs. 33.41 ± 4.48 years, P = 0.003) but lower chromosomal aberration rate of abortus (58.33 % vs. 67.50 %, P = 0.040). A slightly higher incidence of chromosome segmental abnormalities was found in FET than in fresh ET abortion (5.26 % vs. 2.08 %, P = 0.066). CONCLUSIONS: Chromosomal abnormality of fetus is the main cause of SA in the first trimester, no matter pregnancies are conceived through NC, IVF or ICSI. ART is a relatively safety treatment, and it does not enhance aneuploidy rate of abortus. The FET is bad for ongonging pregnancy and the aneuploidy rate were increased with maternal age.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 471-7, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-27209752

RESUMO

Recently considerable researches have focused on monitoring vegetation changes because of its important role in regula- ting the terrestrial carbon cycle and the climate system. There were the largest areas with high-altitudes in the Qinghai-Tibet Plateau (QTP), which is often referred to as the third pole of the world. And vegetation in this region is significantly sensitive to the global warming. Meanwhile NDVI dataset was one of the most useful tools to monitor the vegetation activity with high spatial and temporal resolution, which is a normalized transform of the near-infrared radiation (NIR) to red reflectance ratio. Therefore, an extended GIMMS NDVI dataset from 1982-2006 to 1982-2014 was presented using a unary linear regression by MODIS dataset from 2000 to 2014 in QTP. Compared with previous researches, the accuracy of the extended NDVI dataset was improved again with consideration the residuals derived from scale transformation. So the model of extend NDVI dataset could be a new method to integrate different NDVI products. With the extended NDVI dataset, we found that in growing season there was a statistically significant increase (0.000 4 yr⁻¹, r² = 0.585 9, p < 0.001) in QTP from 1982 to 2014. During the study pe- riod, the trends of NDVI were significantly increased in spring (0.000 5 yr⁻¹, r² = 0.295 4, p = 0.001), summer (0.000 3 yr⁻¹, r² = 0.105 3, p = 0.065) and autumn respectively (0.000 6 yr⁻¹, r² = 0.436 7, p < 0.001). Due to the increased vegeta- tion activity in Qinghai-Tibet Plateau from 1982 to 2014, the magnitude of carbon sink was accumulated in this region also at this same period. Then the data of temperature and precipitation was used to explore the reason of vegetation changed. Although the trends of them are both increased, the correlation between NDVI and temperature is higher than precipitation in vegetation grow- ing season, spring, summer and autumn. Furthermore, there is significant spatial heterogeneity of the changing trends for ND- VI, temperature and precipitation at Qinghai-Tibet Plateau scale.


Assuntos
Plantas , Análise Espaço-Temporal , Análise Espectral , Monitoramento Ambiental , Tibet
16.
Ying Yong Sheng Tai Xue Bao ; 26(6): 1727-34, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26572025

RESUMO

A two-year (2011-2012 and 2012-2013) field experiment was conducted on one winter wheat cultivar supplied with two levels, of nitrogen (180 and 240 kg N · hm(-2)) under three plant densities (135 x 10(4), 270 x 10(4), and 405 x 10(4) plants · hm(-2)) . The 15N-labeled urea was injected into 20, 60 and 100 cm soil depths, respectively, aiming to investigate the effect of nitrogen and plant density and their interaction on the N uptake, utilization and nitrate nitrogen contents at different soil depths. The results showed that increasing the plant density from 135 x 10(4) to 405 x 10(4) plants · hm(-2) significantly increased the 15N uptake at depths of 20, 60 and 100 cm averagely by 1.86, 2.28 and 2.51 kg · hm(-2), respectively, and increased the above ground N uptake (AGN) , N uptake efficiency (UPE) averagely by 12.6% and 12.6%, respectively, but decreased the N utilization efficiency (UTE) by 5.4%. Compared to the N input of 240 kg N · hm(-2) the 180 kg N · hm(-2) significantly reduced the 15N uptake at depths of 20 and 60 cm averagely by 4. 11 and 1.21 kg · hm(-2), respectively, and significantly increased the 15N uptake at depths of 100 cm averagely by 1.02 kg · hm(-2). Reducing the N input decreased the AGN averagely by 13.5%, but significantly increased the UPE and UTE by 9.4% and 12.2%, respectively. Equivalent grain yield was observed among N input of 180 kg N · hm(-2) with plant density of 405 x 10(4) plants · hm(-2) and N input of 240 kg N · hm(-2) with plant densities of 270 x 10(4) and 405 x 10(4) plants · hm(-2). Increasing the plant density or reducing the N input could encourage the N uptake at deep soil profile and increased UPE and UTE by 13.4% and 11.9%, respectively. Meanwhile, both the nitrate nitrogen contents in 0-200 cm soil layers at maturity and the ratio of the nitrate nitrogen in 100-200 cm soil layers to that in -200 cm were significantly decreased. Therefore, properly decreasing the N input with increasing the plant density of winter wheat was efficient in absorbing N at deep soil, synergistically obtaining high grain yield, UPE and UTE, and reducing the pollution of residual soil nitrate.


Assuntos
Fertilizantes , Nitrogênio/metabolismo , Triticum/fisiologia , Nitratos/metabolismo , Solo/química
17.
Gene ; 573(2): 233-8, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26188156

RESUMO

Azoospermia factor (AZF) microdeletion plays a key role in the genetic etiology of male infertility. The relationship between sY152 deletion in the AZFc region and clinical outcomes is still unclear. This study was to determine the effects of sY152 deletion on the sperm parameters and clinical outcomes of non-obstructive azoospermia or oligozoospermia men after intracytoplasmic sperm injection (ICSI) treatment. A total of 61 infertile men with AZFc microdeletion of the Y chromosome from January 2008 to December 2012 were recruited in the present study. They were divided into two groups, the sY152 group (n=12) and the AZFc group (n=49), based upon whether they have deleted single sY152 marker or all AZFc markers. Fifty azoospermia or oligozoospermia patients without Y chromosome microdeletion were included as the control group. The sperm quality and clinical data were compared among the three groups. Retrospective cohort-control study was performed. The sperm concentration and motility in sY152 group were better than AZFc group (P<0.05), and were comparable to the control group (P>0.05); the morphology, seminal zinc, seminal fructose and seminal carnitine were similar among the three groups (P>0.05). Patients in both sY152 and AZFc groups had lower fertilization rates (68.40% and 70.63%, respectively) than those in the control group (74.91%), and the differences were statistically significant (P<0.05). No significant differences were found in terms of MII oocyte, high-grade embryo rate, 2PN zygote, number of available embryos and transferred embryos, clinical pregnancy rate, implantation rate, miscarriage rate, multiple pregnancy rate, delivery rate, preterm rate and the male/female ratio among the three groups (P>0.05). Single sY152 deletion might cause a lower fertilization rate, but no adverse effects on sperm quality and clinical outcomes were found. Our study may provide more information for consultation in these patients.


Assuntos
Azoospermia/genética , Cromossomos Humanos Y/genética , Oligospermia/genética , Adulto , Azoospermia/terapia , Deleção Cromossômica , Feminino , Estudos de Associação Genética , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Masculino , Oligospermia/terapia , Estudos Retrospectivos , Sitios de Sequências Rotuladas , Injeções de Esperma Intracitoplásmicas , Resultado do Tratamento
18.
Zygote ; 23(5): 771-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25315024

RESUMO

This study aimed to explore whether the presence of a Y chromosome azoospermia factor (AZF) microdeletion confers any adverse effect on embryonic development and clinical outcomes after intracytoplasmic sperm injection (ICSI) treatment. Fifty-seven patients with AZF microdeletion were included in the present study and 114 oligozoospermia and azoospermia patients without AZF microdeletion were recruited as controls. Both AZF and control groups were further divided into subgroups based upon the methods of semen collection: the AZF-testicular sperm extraction subgroup (AZF-TESE, n = 14), the AZF-ejaculation subgroup (AZF-EJA, n = 43), the control-TESE subgroup (n = 28) and the control-EJA subgroup (n = 86). Clinical data were analyzed in the two groups and four subgroups respectively. A retrospective case-control study was performed. A significantly lower fertilization rate (69.27 versus 75.70%, P = 0.000) and cleavage rate (89.55 versus 94.39%, P = 0.000) was found in AZF group compared with the control group. Furthermore, in AZF-TESE subgroup, the fertilization rate (67.54 versus 74.25%, P = 0.037) and cleavage rate (88.96 versus 94.79%, P = 0.022) were significantly lower than in the control-TESE subgroup; similarly, the fertilization rate (69.85 versus 75.85%, P = 0.004) and cleavage rate (89.36 versus 94.26%, P = 0.002) in AZF-EJA subgroup were significantly lower than in the control-EJA subgroup; however, the fertilization rate and cleavage rate in AZF-TESE (control-TESE) subgroup was similar to that in the AZF-EJA (control-EJA) subgroup. The other clinical outcomes were comparable between four subgroups (P > 0.05). Therefore, sperm from patients with AZF microdeletion, obtained either by ejaculation or TESE, may have lower fertilization and cleavage rates, but seem to have comparable clinical outcomes to those from patients without AZF microdeletion.


Assuntos
Azoospermia/genética , Deleção Cromossômica , Cromossomos Humanos Y/genética , Desenvolvimento Embrionário/genética , Fertilização/genética , Oligospermia/genética , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Azoospermia/patologia , Azoospermia/terapia , Estudos de Casos e Controles , Ejaculação , Feminino , Marcadores Genéticos , Humanos , Masculino , Oligospermia/patologia , Oligospermia/terapia , Espermatozoides/química , Resultado do Tratamento
19.
Am J Reprod Immunol ; 73(1): 12-21, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25220906

RESUMO

PROBLEM: To investigate alterations of circulating lymphocyte subsets in women undergoing controlled ovarian stimulation (COS) and survey their relations with pregnancy outcome. METHOD OF STUDY: Fifty-one women were included in this study, of which 24 women were successfully pregnant in the index IVF cycle (the successful pregnancy group, sPG) and 27 women failed to get pregnant (the non-pregnancy group, nPG). Peripheral blood was collected at three time points during COS: on the day before the first GnRHa administration (GnRHa day), on the day before the first Gn administration (Gn day), and on the day before HCG administration (HCG day). The intracellular Th1(IFN-γ and TNF-α)/Th2(IL-10) ratios in circulating Th cells after in vitro phorbol-12-myristate-13-acetate stimulation, the NK cytotoxicity, and the percentage of T, B and NK cell subsets were assessed by flow cytometer. A third group consisting of patients with recurrent implantation failure (RIF group, n = 18) was also enrolled, and the intracellular Th1/Th2 ratios were assessed at HCG day. RESULTS: Intergroup comparison: The ratios of IFN-γ/IL-10 and TNF-α/IL-10 at HCG day were significantly higher (P < 0.05) in nPG than those in sPG, while no change at GnRHa day or Gn day. Higher (P < 0.05) ratios of IFN-γ/IL-10 and TNF-α/IL-10 at HCG day were also observed in RIF group compared to those in sPG. No significant change (P > 0.05) was found in other assessed lymphocyte subsets or in the concentrations of progesterone, estradiol, luteinizing hormone, or follicle-stimulating hormone between the sPG and nPG at the three time points. Intragroup comparison: The ratios of IFN-γ/IL-10 and TNF-α/IL-10 at HCG day were significantly (P < 0.05) lower than those at GnRHa day in sPG, but not in nPG. No significant (P > 0.05) difference was found in other assessed parameters or at other time points. CONCLUSIONS: The ratios of Th1/Th2 were fluctuated during COS, and they might affect the pregnancy outcome of IVF. The circulating NK cytotoxicity and percentage of lymphocyte subsets were relatively stable during the COS.


Assuntos
Linfócitos B/imunologia , Células Matadoras Naturais/imunologia , Subpopulações de Linfócitos/imunologia , Células Th1/imunologia , Células Th2/imunologia , Circulação Sanguínea , Células Cultivadas , Gonadotropina Coriônica/administração & dosagem , Citocinas/metabolismo , Citotoxicidade Imunológica , Implantação do Embrião , Transferência Embrionária , Feminino , Fertilização In Vitro/métodos , Seguimentos , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/análogos & derivados , Humanos , Ativação Linfocitária , Indução da Ovulação/métodos , Gravidez , Equilíbrio Th1-Th2 , Falha de Tratamento
20.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 31(5): 641-5, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25297600

RESUMO

OBJECTIVE: To explore the incidence and genotypes of glucose-6-phosphate dehydrogenase (G6PD) gene mutations among infertile patients in Shenzhen. METHODS: DNA samples from 851 infertile patients were tested for 25 G6PD gene mutation sites using a multiplex SNaPshot assay. RESULTS: The incidence of G6PD gene mutations among infertile patients in Shenzhen was 17.63%. Male and female abnormal rates were 15.13% and 20.09% respectively. Most of the female abnormal cases were heterozygotes. Mutations involved 11 haplotypes in 10 sites. 1311C> T/IVS-11 93T> C was the most common mutation, accounting for 72.00% (108/150) abnormal cases. Forty three cases of missense mutations were detected, including 19 cases of 1376G> T, 9 cases of 1388G> A, 5 cases of 95A> G and 871G> A/1311C> T/IVS-11 93T> C, 1 case of 202G> A, 835A> T, 1360C> T, 1376G> T and 392G> T/1311C> T/IVS-11 93T> C. CONCLUSION: The incidence of G6PD gene mutations among infertile patients in Shenzhen was high and the mutation types were various. Therefore, the G6PD deficiency genetic screening should be performed prior to assisted reproduction. This investigated results provided valuable basic data for genetic counseling, preimplantation genetic diagnosis and prenatal diagnosis.


Assuntos
Glucosefosfato Desidrogenase/genética , Infertilidade Feminina/genética , Infertilidade Masculina/genética , Mutação , Grupo com Ancestrais do Continente Asiático/genética , China/epidemiologia , Análise Mutacional de DNA , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Incidência , Infertilidade Feminina/etnologia , Infertilidade Masculina/etnologia , Masculino
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