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1.
Insects ; 13(2)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35206756

RESUMO

Ophraella communa is an efficient biocontrol agent used against the invasive weed Ambrosia artemisiifolia. It is an herbivorous insect that feeds on specific plants; the olfactory functions of this insects plays an important role in their search for host plants. There are no reports on O. communa sensilla types, morphology, or chemosensory protein (CSP) genes. In this study, we observed the external structure and distribution of antennal sensilla in adult O. communa antennae by scanning electron microscopy; moreover, we cloned 11 CSPs (CSP1-CSP11) and elucidated their tissue-expression profiles using quantitative real-time polymerase chain reaction. Six types of sensilla were identified: sensilla trichodea (including two subtypes), sensilla chaetica, sensilla basiconica (including two subtypes), sensilla styloconica, sensilla coeloconica, and Böhm bristles. Both male and female antennae had all six types of sensilla, and no sexual dimorphism was noted in sensillar types or distribution. We also found that the expression levels of CSP2, CSP3, CSP4, CSP6, and CSP7 in male and female antennae were higher than those in other tissues, which suggests that these five CSPs may be related to olfactory function in O. communa. Ultimately, our results lay the foundation for interpreting the olfactory functions of adult O. communa.

3.
World J Urol ; 40(2): 505-511, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34811586

RESUMO

PURPOSE: Computational fluid dynamics (CFD) has been used successfully in cardiovascular system research to analyze the physiological processes inside vessels. We evaluated the hydraulic information of urine through the lower urinary tract in a patient with posterior urethral valve (PUV) before and after valve ablation by CFD. METHODS: A set of models of the lower urinary tract were developed based on geometrical data obtained by cystoscopy and voiding cystourethrography. Simulated assumptions and conditions were applied according to prior studies and urodynamic results. We used Fluent CFD 19.0 (Ansys Inc., USA) to compute the velocity and pressure of the fluid regions. The simplification of Bernoulli's formula was applied afterward to calculate the hydraulic energy of different positions. RESULTS: The urine flow rates of the NORMALst, the PUVst, and the POSTst at 5000 Pa were 18.08 ml/s, 11.14 ml/s, and 12.16 ml/s, respectively. Precipitous pressure change was observed around the valve in the PUVst, and the abnormal change was concentrated in the dilated urethra in the POSTst. Major energy dissipations were generated around the valve and the dilated urethra in the PUVst. The energy loss that occurred in the dilated urethra did not improve after the operation. CONCLUSIONS: Our findings are probably indicative of the hydrodynamics changes in the dilated urethra in PUV and need to be confirmed through more improved CFD models in the future. CFD may revolutionize pediatric urologists' perception in the management of urinary disease.


Assuntos
Hidrodinâmica , Obstrução Uretral , Criança , Humanos , Masculino , Projetos Piloto , Estudos Retrospectivos , Uretra/cirurgia
4.
Front Cell Infect Microbiol ; 11: 790036, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869083

RESUMO

Interferon gamma-inducible protein 16 (IFI16) is a DNA sensor protein, which triggers interferon-beta (IFN-ß) production. However, the role of IFI16 in the innate immunity against hepatitis B virus (HBV) remains controversial. Peripheral blood mononuclear cells (PBMCs) and serum specimens were collected from 20 patients with chronic hepatitis B (CHB) receiving Peg-IFN-α2b therapy. IFI16 mRNA/protein of PBMCs and serum IFI16 at baseline and changes during Peg-IFN-α2b treatment were detected. The interaction between IFI16 and HBV DNA in the PBMCs was analyzed using chromatin immunoprecipitation assay. Leukemic T cell line CEM-C7 and HBV-replicating HepG2.2.15 cells were used to test the effects of interferon treatment and HBV replication on IFI16 expression. Compared with healthy controls, lower levels of IFI16 mRNA but more significant expression of IFI16 protein with heterogeneous degradation were detected in PBMCs of CHB patients. Early changes in IFI16 mRNA, but not IFNB mRNA of PBMCs or serum IFI16, were correlated to HBeAg seroconversion of Peg-IFN-α2b therapy. An interaction between IFI16 and HBV DNA was detected in the PBMCs. In the cultured HepG2.2.15 and CEM-C7 cells, interferons resulted in the translocalization of IFI16 from the cytoplasm to the nucleus and inhibited IFI16 degradation. IFI16 of PBMCs may play a role in sensing HBV infection, and early change in IFI16 mRNA of PBMCs is valuable to predict HBeAg seroconversion in Peg-IFN-α2b treatment. The influences on IFI16 degradation and subcellular location may present a molecular mechanism of antiviral activity of interferon.


Assuntos
Antivirais , Hepatite B , Proteínas Nucleares/imunologia , Fosfoproteínas/imunologia , Antivirais/uso terapêutico , Células Cultivadas , Hepatite B/tratamento farmacológico , Hepatite B/imunologia , Humanos , Interferon alfa-2/uso terapêutico , Interferon-alfa/uso terapêutico , Leucócitos Mononucleares , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico
5.
World J Gastrointest Oncol ; 13(7): 673-683, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34322196

RESUMO

Tumor-specific neoantigens, which are expressed on tumor cells, can induce an effective antitumor cytotoxic T-cell response and mediate tumor regression. Among tumor immunotherapies, neoantigen vaccines are in early human clinical trials and have demonstrated substantial efficiency. Compared with more neoantigens in melanoma, the paucity and inefficient identification of effective neoantigens in hepatocellular carcinoma (HCC) remain enormous challenges in effectively treating this malignancy. In this review, we highlight the current development of HCC neoantigens in its generation, screening, and identification. We also discuss the possibility that there are more effective neoantigens in hepatitis B virus (HBV)-related HCC than in non-HBV-related HCC. In addition, since HCC is an immunosuppressive tumor, strategies that reverse immunosuppression and enhance the immune response should be considered for the practical exploitation of HCC neoantigens. In summary, this review offers some strategies to solve existing problems in HCC neoantigen research and provide further insights for immunotherapy.

6.
Ying Yong Sheng Tai Xue Bao ; 32(6): 2107-2118, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212617

RESUMO

Epikarst is the core area of karst critical zone, with important hydrologic regulation and storage function. However, the effects of karst development degree on hydrologic characteristics of epikasrt is still unclear. We used geophysical exploration and hydrogeological techniques, combined with the dynamic monitoring of moisture and water levels, to quantify the karst development degrees and their hydrologic characteristics on slope lands. We analyzed the responses of soil-epikarst systems to rainfall. Results showed that geophysical exploration technology could be well applied to the detection of surface-subsurface structures in the karst areas. The average thickness of soil and surface karst zone on the slope was less than 0.63 m and 2.60 m, respectively. The slopes of strong-karstification characterized by high apparent resistivity, well-developed joint fractures, and strong permeability (0.73 m·d-1). Such a result indicated that epikarst could regulate precipitation. The responses of soil moisture had a larger rainfall threshold (>20.50 mm·d-1) and the water level was determined by rainfall amount. In contrast, the slope with weak-karstification had low apparent resistivity and weak permeability (0.07 m·d-1). Moisture and water level were sensitive to rainfall. Karst channels were developed locally at 240-300 cm with a permeability coefficient of up to 432 mm·d-1. Obvious preferential flow was observed in extreme rainfall events on this slope, which could induce flood disaster in the adjacent depression. Our results would provide scientific basis for further research on water resources regulation, management, and eco-hydrology in karst areas of southwest China.


Assuntos
Hidrologia , Solo , Carbonato de Cálcio , China , Monitoramento Ambiental , Magnésio
7.
Asian J Androl ; 23(5): 527-531, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33723097

RESUMO

We aimed to explore the associations between the age at which children undergo surgery for hypospadias and a range of social and clinical factors in a single center. Our aim was to promote the early surgical treatment of children with hypospadias. For a 6-year period, social and clinical data were collected from all children undergoing surgery to repair hypospadias in Children's Hospital of Chongqing Medical University (Chongqing, China), located in southwest of China. We analyzed the correlations between age at surgery and a range of social and clinical factors. A total of 1611 eligible cases were recruited, with a mean age of 54.3 months and a median age of 42 months: 234 cases (14.5%) were classified into a "timely operation" group, 419 (26.0%) cases into a "subtimely operation" group, and 958 (59.5%) cases into a "delayed operation" group. According to multivariate regression analyses, the higher the regional economic level, the closer the urethral opening to the perineum, and the higher the educational level of the guardians was, the younger the children were when they underwent the initial surgery for hypospadias; this was also the case for families without other children. Our subgroup analysis showed that the primary educational level of the guardians was a risk factor for subtimely surgery in their children (odds ratio [OR] = 1.52, 95% confidence interval [CI]: 1.08-2.15, P < 0.05). A lower regional economic level (OR = 1.87, 95% CI: 1.26-2.78, P < 0.01), a lower educational level of the guardians (OR = 3.84, 95% CI: 2.31-6.41, P < 0.01), and an anterior-segment urethral opening (OR1 [vs middle hypospadias] = 2.07, 95% CI: 1.42-3.03; OR2 [vs posterior hypospadias] = 2.63, 95% CI: 1.75-3.95; P < 0.01) were all risk factors for delayed surgery in children.


Assuntos
Fatores Etários , Hipospadia/terapia , Tempo para o Tratamento/estatística & dados numéricos , Criança , Pré-Escolar , China , Humanos , Hipospadia/classificação , Lactente , Masculino , Estudos Retrospectivos , Fatores de Risco
8.
Environ Entomol ; 50(1): 1-11, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33205198

RESUMO

The brown planthopper, Nilaparvata lugens (Stål), is one of the most serious and destructive pests of rice in Asia. Climate warming in tropical regions and extreme-high- or low-temperature events may become limiting factors affecting the survival and distribution of N. lugens. The effects of continuous high temperature (CHT), discontinuous high temperature (DHT), and abnormal low temperature in summer (ALT) on the growth and development of N. lugens were studied under lab conditions. High temperatures and ALT decreased the survival rate of nymphs (in fourth-instar nymphs, CHT, DHT, ALT, and control survival was 46.67% ± 1.67, 31.67% ± 1.67, 48.33% ± 4.41, and 60.00% ± 2.89, respectively, P < 0.05). ALT also prolonged the development of N. lugens nymphs (in fourth-instar nymphs, ALT and control survival was 6.09 ± 0.193 d and 5.39 ± 0.082 d, respectively, P < 0.05). In fifth-instar nymphs, CHT (2.36 ± 0.064 d, P < 0.05) and DHT (2.34 ± 0.048 d, P < 0.05) had little influence on nymphal development compared with the control (2.25 ± 0.012 d, P < 0.05). The three temperature treatments (CHT, DHT, and ALT) decreased the number of eggs produced (61.33 ± 0.067, 62.67 ± 0.882, and 34.00 ± 0.577, respectively, P < 0.05) compared with the control (68.00 ± 1.000, P < 0.05). The female sex ratio decreased after nymphs were subjected to CHT (65.82% ± 0.771, P < 0.05, in fifth-instar nymphs) and ALT (76.01% ± 1.362, P < 0.05) compared with the control (81.63% ± 1.007, P < 0.05). Adults in CHT (25.30 ± 0.182, P < 0.05) and DHT (14.64 ± 0.238, P < 0.05) consumed significantly more food than the control (11.54 ± 0.181, P < 0.05), but adults in ALT (6.54 ± 0.196, P < 0.05) fed significantly less than the control (11.54 ± 0.181, P < 0.05). Hatching rates of eggs under the three temperature treatments (CHT, DHT, and ALT were 69.57% ± 0.215, 71.29% ± 0.529, and 43.13% ± 0.508, respectively, and were significantly lower (P < 0.05) than the control (78.95% ± 1.000, P < 0.05). These experiments revealed that extreme temperatures can influence the growth and development of N. lugens and may affect its distribution. As such, N. lugens remains a serious pest of rice.


Assuntos
Hemípteros , Oryza , Animais , Feminino , Ninfa , Óvulo , Temperatura
9.
Sci Rep ; 10(1): 14538, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883983

RESUMO

Regulatory factor X-5 (RFX5) represents a key transcription regulator of MHCII gene expression in the immune system. This study aims to explore the molecular mechanisms and biological significance of RFX5. Firstly, by analyzing ENCODE chromatin immunoprecipitation (ChIP)-seq in HepG2 and TCGA RNA-seq data, we discovered lysine-specific demethylase 4A (KDM4A), also named JMJD2A, to be a major downstream target gene of RFX5. Moreover, RFX5 was verified to bind directly to the KDM4A's promoter region and sequentially promoted its transcription determined by the ChIP-PCR assay and luciferase assay. In addition, RFX5-dependent regulation of KDM4A was demonstrated in HCC. Compared with adjacent non-tumor tissues, the expression levels of KDM4A were significantly raised in HCC tumor tissues. Notably, elevated levels of KDM4A were strongly correlated with HCC patient prognosis. Functionally, KDM4A overexpression largely rescued the growth inhibitory effects of RFX5 deletion, highlighting KDM4A as a downstream effector of RFX5. Mechanistically, the RFX5-KDM4A pathway promoted the progression of the cell cycle from G0/G1 to S phase and was protective against cell apoptosis through regulation of p53 and its downstream genes in HCC. In conclusion, RFX5 could promote HCC progression via transcriptionally activating KDM4A expression.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fatores de Transcrição de Fator Regulador X/metabolismo , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Células Hep G2 , Humanos , Imuno-Histoquímica , Histona Desmetilases com o Domínio Jumonji/genética , Neoplasias Hepáticas/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição de Fator Regulador X/genética , Análise de Sequência de RNA , Análise Serial de Tecidos , Ativação Transcricional/genética , Ativação Transcricional/fisiologia
10.
Am J Cancer Res ; 9(6): 1183-1200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31285951

RESUMO

Neoadjuvant chemotherapy (NAC) may provide survival benefits for patients with advanced esophageal squamous cell carcinoma. However, tumor cells can display primary or secondary resistance to paclitaxel (PTX), a primary component of induction chemotherapy regimen. To identify genes capable of conveying PTX resistance, we performed a genome-wide CRISPR transcriptional activation library in human KYSE-180 cells. High throughput next generation sequencing was further applied to establish the phenotype-to-genotype relationship. Our highest-ranking hits are CDKN1A, TSPAN4, ELAVL2, JUNB and PAAF1. We generated evidence that esophageal tumors with high CDKN1A, ELAVL2 and TSPAN4 levels, quantified using qRT-PCR and Western blot assays, showed poorer chemotherapy response. Higher expression levels of TSPAN4 and ELAVL2 protein are independent risk factors for poor chemotherapy response in ESCC patients. We then found that overexpression of CDKN1A, ELAVL2 or TSPAN4 in ESCC cell lines significantly promoted the resistance to PTX by inhibiting cell apoptosis. Interestingly, ESCC cells overexpressed CDKN1A, ELAVL2 or TSPAN4 also acquired resistance to cisplatin (DDP). This phenomenon may be explained by cross-resistance of chemotherapy. We additionally found an association between ELAVL2 and CDKN1A, which may be regarded as the upstream and downstream factors that synergistically involved in the regulation of chemo-resistance in ESCC. Therefore, our study demonstrated that the genome-wide CRISPR activation library is a powerful strategy for the discovery of chemo-resistant genes critical for ESCC and we reported the first evidence that the ELAVL2-CDKN1A axis may be an important mechanism involved in chemo-resistance in ESCC.

11.
Chin Med J (Engl) ; 132(13): 1572-1581, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31188160

RESUMO

BACKGROUND: Our previous studies have shown that regulatory factor X5 (RFX5), a classical transcription regulator of MHCII genes, was obviously overexpressed in hepatocellular carcinoma (HCC) tumors. However, the role of RFX5 in the carcinogenesis and progress of HCC remains unknown. This study aimed to reveal its biological significance and the underlying mechanism in HCC. METHODS: RFX5 mRNA expression level and copy number variation in HCC tumors and cell lines were determined by analyzing deposited data sets in the Cancer Genome Atlas and Gene Expression Omnibus database. The biological significance of RFX5 in HCC was investigated by monitoring the colony formation and subcutaneous tumor growth capacity when RFX5 was silenced with lentiviral short hairpin RNA and CRISPR/Cas9 system in HCC cell lines. The downstream gene transcriptionally activated by RFX5 in HCC cells was determined by chromatin immunoprecipitation and luciferase reporter assay. The involvement of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein theta (YWHAQ) in HCC development was further determined by performing colony formation rescue assay and subcutaneous tumor growth rescue experiment. The association of YWHAQ with recurrence-free survival of patients with HCC was assessed by Kaplan-Meier analysis. Moreover, apoptosis level and the protein level of p53 pathway were determined to reveal the mechanism of RFX5 in driving HCC development. RESULTS: RFX5 was amplified and highly overexpressed in HCC tumor tissues compared with the corresponding non-tumor tissues. The mRNA expression level of RFX5 was significantly correlated with its DNA copy number (r = 0.4, P < 0.001). Functional study demonstrated that RFX5 was required for both clonogenic forming in vitro and subcutaneous tumor growth in vivo of HCC cells. Further study identified YWHAQ, namely 14-3-3 tau, as a key downstream transcriptional target gene of RFX5, which was tightly regulated by RFX5 in HCC. Moreover, overexpression of YWHAQ largely rescued the clonogenic growth of HCC cells that was suppressed by RFX5 knockdown. In addition, overexpression of YWHAQ in primary tumor was linked to poor prognosis of patients with HCC. These results demonstrated that YWHAQ was a downstream effector of RFX5 in HCC. Notably, RFX5-YWHAQ pathway could protect cells from apoptosis by suppressing the p53 and Bax in HCC. CONCLUSION: RFX5 is a putative HCC driver gene that plays an important role in the development and progression of HCC by transactivating YWHAQ and suppressing apoptosis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fatores de Transcrição de Fator Regulador X/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Apoptose/genética , Apoptose/fisiologia , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Variações do Número de Cópias de DNA/genética , Variações do Número de Cópias de DNA/fisiologia , Progressão da Doença , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Plasmídeos/genética , Fatores de Transcrição de Fator Regulador X/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Análise Serial de Tecidos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Ying Yong Sheng Tai Xue Bao ; 30(3): 759-767, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30912367

RESUMO

Although lack of soil coverage, rock outcrops with developed fractures in karst region can maintain water consumption of plants with different life forms. Water sources for plants on these habi-tats are unclear. Isolated rocky outcrop with relatively simple sources of water was selected for this study. We focused on typical plant species that still thrived after excluding rainfall (removing the water supply to the shallow water) over one year, compared with the same plant species living without rain shelter (always receiving rainfall supplies). Water sources of three representative tree species (Radermachera sinica, Celtis biondii, and Pittosporum tonkinense) were analyzed by using stable isotope techniques and combining with the measurement of plant water potential. The results showed that all the three species depended on deep water sources with similar isotopic values to spring water under rain-sheltered condition, during the rainy season, which explained why plants could still grow normally after rainfall-exclusion over one year. The predawn water potential of R. sinica and P. tonkinense under rain-sheltered condition was not significantly different from those living in natural conditions, which indicated both species were not under water stress. The predawn water potential of C. biondii under rain-sheltered condition was significantly lower than individuals living in natural conditions, which indicated it was under water stress. Under natural condition, water isotope values of stems of all the three species were significantly lower than that under rain-sheltered condition and were within the range of fluctuation of recent rainwater isotope values, indicating that these plants relied on shallow water sources that dominated by recent rainfall. Under both rain-sheltered and natural conditions, there was no obvious difference between the predawn water potential and the midday water potential of P. tonkinense, showing a conservative water use strategy. The midday water potential of other two species was significantly lower than the predawn water potential, showing a profligate/opportunistic water use strategy. Our results indicated that the ability to utilize shallow and deep water sources is key for the plants growing on the habitat of Karst rock outcrops where they could adapt different water environments and maintain diversified water use strategies under the condition with no soil coverage.


Assuntos
Chuva , Água , Ecossistema , Plantas , Solo , Árvores
13.
Chin Med J (Engl) ; 131(23): 2827-2835, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30511685

RESUMO

Background: DNA replication and sister chromatid cohesion 1 (DSCC1) (also called DCC1) is a component of an alternative replication factor C complex that loads proliferating cell nuclear antigen onto DNA during S phase of the cell cycle. It is located at 8q24 and frequently amplified in hepatocellular carcinoma (HCC). However, the role of DSCC1 in the carcinogenesis and progress of HCC has not been fully investigated. Here, we aimed to assert the importance of DSCC1 in the HCC. Methods: In this study, copy number variation data and RNA sequencing data were used to calculate the DNA copy number and mRNA expression of DSCC1 in HCC. Quantitative polymerase chain reaction, Western blotting, and immunohistochemistry analysis were used to determine the mRNA and protein level of DSCC1 in HCC. The Kaplan-Meier analysis and univariate and multivariate Cox regression analysis were used to assess the association of DSCC1 with the overall survival (OS) of HCC patients. Moreover, lentiviral shRNA was used to knockdown DSCC1, and then, colony-forming assay, cell cycle assay, and cell proliferation assay were performed to evaluate the impact of DSCC1 silencing on HCC cell lines. Results: We found that DSCC1 was amplified and highly expressed in HCC tumor tissues than in nontumor tissues. We then found that the overexpression of both mRNA and protein of DSCC1 was linked to the bad prognosis of HCC patients. Astonishingly, the protein level of DSCC1 was an independent prognostic factor for OS (hazard ratio, 1.79; 95% confidence interval, 1.17-2.74; P = 0.007). Furthermore, the clonogenic capacity of DSCC1-amplified HCC cell lines (MHCC-97H, MHCC-97L, and Hep3B) was significantly inhibited by transduction of a lentiviral shRNA that targets DSCC1. We also showed that knockdown of DSCC1 induced G0-G1 cell cycle arrest (increased from 60% to more than 80%) and greatly inhibited the proliferation of HCC cell lines. Conclusion: These results suggest that DSCC1 is a putative HCC driver gene that promotes proliferation and is associated with poor prognosis in HCC.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Replicação do DNA/fisiologia , Neoplasias Hepáticas/patologia , Western Blotting , Ciclo Celular/genética , Ciclo Celular/fisiologia , Pontos de Checagem do Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Replicação do DNA/genética , Feminino , Células Hep G2 , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase em Tempo Real
14.
Ying Yong Sheng Tai Xue Bao ; 29(4): 1117-1124, 2018 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29726219

RESUMO

This study focused on bedrock outcrops, a very common habitat in karst region of southwest China. To reveal the responses of plant transpiration to natural rainfall and continuous drought, two tree species typical to this habitat, Radermachera sinica and Triadica rotundifolia, were selected as test materials. A rainout shelter was used to simulate continuous drought. The sap flow dynamics were monitored using the method of Granier's thermal dissipation probe (TDP). Our results showed that sap flow density increased to different degrees after rain in different stages of the growing season. Sap flow density of the deciduous species T. rotundifolia was always higher than that of the semi-deciduous species R. sinica. After two months without rainfall input, both species exhibited no obvious decrease in sap flow density, indicating that rainfall was not the dominant source for their water uptake, at least in the short-term. Based on the regression relationships between sap flow density and meteorological factors before and after rainfall, as well as at different stages of continuous drought, we found that the dynamics of meteorological factors contributed little to plant transpiration. The basic transpiration characteristics of both species were not changed in the circumstance of natural rainfall and short-term continuous drought, which would be closely related to the special water storage environments of bedrock outcrops and the reliance on deep water sources by tree species.


Assuntos
Secas , Transpiração Vegetal , China , Ecossistema , Chuva , Estações do Ano , Árvores , Água
15.
Sci Rep ; 7(1): 1404, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28469174

RESUMO

Hepatitis B Virus core protein (HBc) has multiple roles in the viral lifecycle: viral assembly, compartment for reverse transcription, intracellular trafficking, and nuclear functions. HBc displays assembly polymorphism - it can assemble into icosahedral capsid and aberrant non-capsid structures. It has been hypothesized that the assembly polymorphism is due to allosteric conformational changes of HBc dimer, the smallest assembly unit, however, the mechanism governing the polymorphic assembly of the HBc dimer is still elusive. By using the experimental antiviral drug BAY 41-4109, we successfully transformed the HBc assembly from icosahedral capsid to helical tube. Structural analyses of HBc dimers from helical tubes, T = 4 icosahedral capsid, and sheet-like HBc ensemble revealed differences within the inter-dimer interface. Disruption of the HBc inter-dimer interface may likely promote the various assembly forms of HBc. Our work provides new structural insights into the HBV assembly mechanism and strategic guide for anti-HBV drug design.


Assuntos
Vírus da Hepatite B/química , Vírus da Hepatite B/fisiologia , Proteínas do Core Viral/química , Montagem de Vírus , Escherichia coli , Humanos , Modelos Moleculares , Multimerização Proteica , Estrutura Terciária de Proteína , Piridinas/farmacologia , Pirimidinas/farmacologia , Proteínas do Core Viral/ultraestrutura
16.
Ying Yong Sheng Tai Xue Bao ; 28(7): 2186-2196, 2017 Jul 18.
Artigo em Chinês | MEDLINE | ID: mdl-29741049

RESUMO

The traditional hydrology method, stable hydrogen and oxygen isotope technology, and rainfall simulation method were combined to investigate the hydrological function of small experimental plots (2 m×1.2 m) of contrasting architecture in Northwest Guangxi dolomite area. There were four typical catenary soils along the dolomite peak-cluster slope, which were the whole-sand, up-loam and down-sand, the whole loam, up-clay and down-sand soil types, respectively. All the experimental plots generated little amounts of overland runoff and had a high surface infiltration rate, ranging from 41 to 48 mm·h-1, and the interflow and deep percolation were the dominant hydrological progress. The interflow was classified into interflow in soil clay A and C according to soil genetic layers. For interflow in soil clay A, matrix flow was generated from the whole-sand, up-loam and down-sand, up-clay and down-sand soil types, but preferential flow dominated in the whole-loam soil type. As for interflow in soil clay C, preferential flow dominated in the whole-loam, up-clay and down-sand, up-loam and down-sand soil types. The soils were shallow yet continuously distributed along the dolomite slope. The difference of hydrological characteristics in soil types with different architectures mainly existed in the runoff generation progress of each interface underground. It proved that the a 3-D perspective was needed to study the soil hydrological functions on dolomite slope of Northwest Guangxi, and a new way paying more attention on underground hydrological progress should be explored to fully reveal the near-surface hydrological processes on karst slope.


Assuntos
Carbonato de Cálcio , Magnésio , Solo , China , Hidrologia
17.
Ying Yong Sheng Tai Xue Bao ; 28(7): 2197-2206, 2017 Jul 18.
Artigo em Chinês | MEDLINE | ID: mdl-29741050

RESUMO

With the development of the binary structure of karst landforms, surface water is largely drained with rapid loss of nutrients. However, the pathway and mechanism of nutrient loss remain elusive. From a three-dimensional (vegetation-soil-epikarst system) perspective of a critical zone in karst area, this study conducted rainfall induced runoff and nitrogen loss monitoring during monsoon in karst shrub slopes. Isotope-based (D and 18O) hydrograph separation method was applied to partition the ratio of 'old' and 'new' water in main hydrological path. The main results were summarized as follows. Deep percolation and interflow were the dominant hydrological pathways, accoun-ting for 71% and 9% of total rainfall amount, respectively. In contrast, surface runoff occupied less than 2%. Both deep percolation and interflow were dominated with 85% and 61% of old water, respectively. The highest nitrate concentration occurred in deep percolation (1.97 mg·L-1), while the highest ammonium nitrogen concentration occurred in interflow (1.18 mg·L-1). Deep percolation contributed 89.4% of total nitrogen loss, which was significantly higher than that of surface runoff and interflow. Old water ratio showed a significant positive correlation with nitrate nitrogen concentration, ammonium nitrogen concentration, and total nitrogen loss, suggesting it might be the main agent driving nitrogen migration for the whole soil-epikarst system in karst hillslopes. The results would provide scientific basis for rational allocating water resources and developing nutrient loss control technology in karst region of southwestern China.


Assuntos
Nitrogênio , Solo , Movimentos da Água , China , Monitoramento Ambiental , Isótopos de Oxigênio
18.
Ying Yong Sheng Tai Xue Bao ; 28(7): 2361-2368, 2017 Jul 18.
Artigo em Chinês | MEDLINE | ID: mdl-29741071

RESUMO

Karst regions, which account for about 15% of the terrestrial surface area, are characte-rized by specific hydrogeological structure different from most non-karst regions. Thus, many research methods that are used in non-karst regions cannot be directly used in karst regions. This issue is especially relevant to research on plant water sources. In this paper, origins and possible solutions to the common problems associated with research on water sources used by karst plant species were reviewed. Four questions were addressed: 1) why is it important to determine plant water source in karst regions? 2) Why are stable isotopes used? 3) What are the challenges associated with using stable isotopes in karst regions? 4) What are the probable solutions for these challenges? This review emphasized the advantages of using stable isotope techniques to identify sources of water used by karst plant species and the challenges associated with satisfying the prerequisites of this method. It is suggested that sources of water used by plant species in karst regions need not to be divided into specific depths and the method of identifying sources of water used by plant species based on their hydrologic properties was much applicable.


Assuntos
Isótopos , Plantas , Água
19.
Environ Sci Pollut Res Int ; 23(24): 25267-25279, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27687762

RESUMO

Knowledge of the temporal variability of soil water content (SWC) at the hillslope scale is essential for guiding rehabilitation strategies and for optimizing water resource management in the karst region of southwest China. This study aimed to use temporal stability analysis to upscale point-scale measurements to represent mean areal SWC on two typical karst hillslopes. Based on a grid sampling scheme (10 m × 10 m) applied to two 90 m × 120 m plots located on two hillslops, the SWC at a depth of 0-16 cm was measured 11-12 times across 259 sampling points, using time domain reflectometry (TDR) from April 2011 to October 2012. Soil texture, bulk density (BD), saturated hydraulic conductivity (K s ), organic carbon (SOC), rock fragment content (RFC), and site elevation (SE) were also measured at these locations. Results showed the hillslope with more shrub cover was wetter than the hillslope with mixed grass-shrub cover. This difference was related to the differences in soil texture, soil hydraulic permeability, and topography. Through a comparison of values obtained with the Spearman correlation coefficient (r s ), standard deviation of mean relative difference (SDRD), and mean absolute bias error (MABE), we inferred that there is a higher degree of temporal stability for SWC in wet conditions than in drier conditions on the two hillslopes. Based on the values of the index of temporal stability (ITS), which combine the mean relative difference (MRD) and SDRD, the two locations were determined to be representative of mean SWC on both hillslopes. Moreover, these locations captured changes in mean SWC (NSCE = 0.69, and 0.65, and RMSE = 1.96, and 1.96 %, respectively). This demonstrates the feasibility of using the temporal stability of SWC to acquire mean SWC on karst hillslopes of southwestern China. The indirect method, which estimates mean SWC by considering the offset between the mean and the measurement value at a time-stable location, predicted mean SWC (NSCE = 0.86, and 0.76, and RMSE = 1.29, and 1.63 %, respectively) more precisely than the direct method (mean SWC directly measured at a time-stable location), because it eliminates deviation by introducing a constant offset (MRD). We recommended the use of the indirect method to acquire mean SWC values, when an allowable bias of 5 % for both MRD and SDRD can not be achieved. In addition, we found that soil texture, RFC, and elevation affect the pattern of SWC on the shrub hillslope. These results are expected to be useful for monitoring soil water dynamics on karst hillslopes, especially for restoration purposes.


Assuntos
Ecossistema , Solo/química , Água/análise , China , Poaceae
20.
Ying Yong Sheng Tai Xue Bao ; 27(6): 1708-1714, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29737676

RESUMO

Based on three manually excavated trenches (projection length of 21 m, width of 1 m) along a typical Karst hillslope, the changing trends for soil-bedrock structure, average water content of soil profile and soil-bedrock interface water content along each individual trench were studied. The effect of irregular bedrock topography on soil moisture distribution was discussed. The results showed that the surface topography was inconsistent with the bedrock topography in the Karst hill-slopes. The bedrock topography was highly irregular with a maximum variation coefficient of 82%. The distribution pattern of soil profile of moisture was significantly affected by the underlying undulant bedrock. The soil water content was related to slope position when the fluctuation was gentle, and displayed a linear increase from upslope to downslope. When the bedrock fluctuation increased, the downslope linear increasing trend for soil water content became unapparent, and the spatial continuity of soil moisture was weakened. The soil moisture was converged in rock dents and cracks. The average water content of soil profile was significantly positively correlated with the soil-bedrock interface water content, while the latter responded more sensitively to the bedrock fluctuation.


Assuntos
Solo , Água , China
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