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1.
Scand J Immunol ; : e13365, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38436518

RESUMO

The presence of autoantibodies is closely associated with the occurrence and development of cancer. Autoantibodies can be used as biomarkers for early breast cancer diagnosis. However, the relationship between autoantibodies and the prognosis of breast cancer patients remains elusive. This retrospective study aimed to investigate the correlation between the presence of autoantibodies and outcomes in breast cancer patients. This study included a total of 155 patients from People's Hospital of Henan University (Zhengzhou, China) who were diagnosed with breast cancer from January 2017 to December 2021. The enrolled patients' clinicopathological features were collected, and 88 patients were ultimately involved in the analysis. Univariate and multivariate Cox regression analyses were performed to search for the risk factors related to the poor prognosis of breast cancer patients. The association between the presence of autoantibodies and patients' survival was analysed using Kaplan-Meier curves. After screening, there were 38 autoantibody-positive cases and 50 autoantibody-negative cases. Breast cancer patients with autoantibody-positive had a 57% lower risk of death compared with autoantibody-negative patients. Multivariate Cox regression analysis indicated that the presence of autoantibody could be a potential prognostic predictor for breast cancer, independent of age, histological grade, pathological classification, clinical stage, and the expression levels of hormonal receptors. In addition, autoantibody-positive breast cancer patients had longer progression-free survival and overall survival compared with autoantibody-negative cases. Positive autoantibody was found as an independent biomarker of better prognosis in breast cancer patients, providing a new strategy for the prognostic assessment of breast cancer patients.

2.
Cancer Sci ; 111(11): 4000-4011, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798273

RESUMO

Heterotypic interactions between tumor cells and macrophages can enable tumor progression and hold potential for the development of therapeutic interventions. However, the communication between tumors and macrophages and its mechanism are poorly understood. Here, we find that tumor-associated macrophages (TAM) from tumor-bearing mice have high amounts of lipid as compared to macrophages from tumor-free mice. TAM also present high lipid content in clinical human gastric cancer patients. Functionally, TAM with high lipid levels are characterized by polarized M2-like profiling, and exhibit decreased phagocytic potency and upregulated programmed death ligand 1 (PD-L1) expression, blocking anti-tumor T cell responses to support their immunosuppressive function. Mechanistically, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis identifies the specific PI3K pathway enriched within lipid-laid TAM. Lipid accumulation in TAM is mainly caused by increased uptake of extracellular lipids from tumor cells, which leads to the upregulated expression of gamma isoform of phosphoinositide 3-kinase (PI3K-γ) polarizing TAM to M2-like profiling. Correspondingly, a preclinical gastric cancer model is used to show pharmacological targeting of PI3K-γ in high-lipid TAM with a selective inhibitor, IPI549. IPI549 restores the functional activity of macrophages and substantially enhances the phagocytosis activity and promotes cytotoxic-T-cell-mediated tumor regression. Collectively, this symbiotic tumor-macrophage interplay provides a potential therapeutic target for gastric cancer patients through targeting PI3K-γ in lipid-laden TAM.


Assuntos
Metabolismo dos Lipídeos , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/metabolismo , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Imunofluorescência , Humanos , Imunofenotipagem , Lipidômica , Ativação de Macrófagos/genética , Camundongos , Modelos Biológicos , Fagocitose , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Gástricas/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia
3.
J Med Virol ; 92(12): 3743-3749, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31930525

RESUMO

To evaluate the prevalence of human papillomavirus (HPV) infection and its genotype among women with cervical lesions in Henan Province, central China. A total of 1317 cervical scrapes from patients with cervical intraepithelial neoplasia 1 (CIN1) (n = 91), CIN2/3 (n = 466), and cervical cancer (CC; n = 760) were collected from 2013 to 2018, and then tested for HPV genotypes using polymerase chain reaction followed by flow-through hybridization assay. The prevalence of HPV was 62.64% for patients with CIN1, 86.91% for patients with CIN2/3%, and 89.21% for patients with CC. In total, the HPV prevalence was 86.56%, and the most common HPV type was HPV16 (58.77%) followed by HPV58 (10.33%), 18 (7.67%), 52 (6.61%), and 33 (5.54%). In this study, the high-risk HPV cumulative attribution rate of nine-valent vaccine coverage was markedly higher than that of bivalent or quadrivalent vaccine coverage in each histopathological category or overall (P < .001). Single HPV infection was the main infection category in each histopathological diagnosis, and the total infection rate was 65.83% (867/1317; P < .001). The prevalence of HPV16 or single HPV infection increased with the severity of cervical lesions (P < .001). HPV16, 58, 18, 52, and 33 may be predominant high-risk factors for cervical lesions in Henan Province. The nine-valent prophylactic HPV vaccine is more effective than a bivalent or quadrivalent vaccine for protecting women from CC in the region.

4.
Artigo em Zh | MEDLINE | ID: mdl-26541030

RESUMO

OBJECTIVE: To investigate the relationship between Clonorchis sinensis infection and the gallbladder stone type in patients with cholelithiasis in the endemic area of clonorchiasis. METHODS: Gallbladder stones were collected from 598 patients with cholelithiasis through minimally invasive gallbladder-preserving cholelithotomy in the Sixth People's Hospital of Nansha District from May 2009 to October 2012. The stone samples were analyzed for composition by Fourier transform infrared spectroscopy to identify their types. The Clonorchis sinensis eggs were detected in the stones by microscopic examination, and the detection rates of eggs were calculated for different stone types. Then the clinical characteristics and biochemical indicators were compared among patients with different types of stones, as well as between Clonorchis sinensis egg-positive and -negative patients with the calcium-carbonate type of stones. Some calcium-carbonate stones positive for Clonorchis sinensis eggs were randomly selected for further scanning electron microscopy (SEM) examination. RESULTS: Of the stones from 598 patients, 234 (39.1%) were cholesterol type, 133 (22.2%) bile pigment type, 112(18.7%) calcium-carbonate type, 86 (14.4%) mixed types and 33(5.5%) were others. The detection rate of Clonorchis sinensis eggs in these types was 6% (15/234), 44% (59/133), 60% (67/112), 36% (31/ 86) and 30% (10/33), respectively, being highest in calcium-carbonate stones while lowest in cholesterol stones. The Co2-combining power of the plasma was higher in patients with calcium-carbonate and mixed stones than in those with cholesterol stones (P < 0.05), and the CO2-combining power of the bile and biliary pH were both higher in patients with calcium-carbonate types than in those with other types (P < 0.05). In addition, in patients with calcium-carbonate stones, the CO2-combining powers of the plasma and the bile, as well as biliary pH were all higher in the egg-positives than in the egg-negatives. Further, both light microscopy and SEM revealed adherence of the Clonorchis sinensis eggs to calcium-carbonate crystals. CONCLUSION: The infection rate of Clonorchis sinensis is higher in patients with calcium-carbonate gallbladder stones than in those with other types of stones.


Assuntos
Clonorquíase , Clonorchis sinensis , Animais , Bile , Cálculos Biliares , Humanos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Ecol Evol ; 14(2): e10927, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38414571

RESUMO

Plant reproductive ecology is one of the research hotspots in ecology. With the increasing attention paid to the conservation of plant diversity, the research on reproductive characteristics and flowering biological characteristics of more species has attracted more attention. However, plant reproduction is affected by multiple interacting factors such as pollen limitation and resource availability. Vitex negundo var. heterophylla (Franch.) Rehder (Lamiaceae) is a significant species for water and soil conservation. Previous studies have revealed its mating system by the biological characteristics of flowering and SSR markers, but its reproductive strategies remain to be further studied. We evaluated reproductive success through artificial pollination to explore the reproductive characteristics of V. negundo var. heterophylla for the first time. From the results of fruit set, there is a mixed mating system dominated by outcrossing in V. negundo var. heterophylla accompanied by self-compatibility, and it cannot carry out autonomous selfing. Our data show the pollinator-mediated interaction in the success of reproduction, whereas the effect of anemophily is very weak. And the seed germination rate of inbred line progenies was lower than that of hybrid progenies, which is suspected to be caused by inbreeding depression. The research will provide scientific information for the protection and conservation of V. negundo var. heterophylla from the point of view of reproduction. In sum, the results are necessary to protect animal vectors in the background of insect decline.

6.
Sci Rep ; 14(1): 13432, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862586

RESUMO

Despite limited research on refractory and/or endocrine therapy failure in elderly metastatic breast cancer (MBC) patients, a prior study showed that low-dose oral cyclophosphamide (CY) can improve the overall survival rate of MBC patients, possibly through the immunoregulation of regulatory T cells (Tregs). We preliminarily investigated the combination of endocrine therapy (ET) with oral low-dose CY as salvage therapy in elderly patients via peripheral blood regulatory T-cell analyses. In addition, we evaluated the associations of tumor tertiary lymphoid structures (TLSs) with therapeutic outcomes. HR+/HER2- advanced breast cancer patients who received low-dose CY combined with ET or ET only from April 2015 to August 2021 were enrolled in this retrospective study. The primary outcome was the clinical control rate (CCR), and the secondary outcome was progression-free survival (PFS). Circulating T lymphocyte subpopulations represented by Tregs were monitored during treatment by flow cytometry methods. TLSs wereconfirmed by hematoxylin-eosin staining of pretreatment specimens, and CD3, CD4, and Foxp3 were detected using Opal multicolor immunofluorescence. A total of 85 patients who received CY + ET and 50 patients who received ET only were enrolled, the percentage of patients who received CCR was 73% (62/85) vs. 70% (45/50), and the objective response rate (ORR) was 28% (24/85) vs. 24% (12/50). No deaths occurred during the study period. The mean PFS time was 13 vs. 11 months (P = 0.03). In the CY + ET group, decreases in CD4+/CD25+/Foxp3+ T cells (P < 0.001) were favorable for both clinical control and prolonged PFS (P < 0.001). Compared with patients without TLSs, those with TLSs were more likely to have better clinical control and PFS (mean time = 6 months), and a greater number of Treg cells during TLS pretreatment correlated with longer PFS (P = 0.043). Oral low-dose CY combined with standard ET exerts immunological effects by decreasing Treg levels to achieve improved clinical responses. Moreover, patients with TLSs might benefit more from such therapy than those without TLSs, and a high Treg cell count in TLSs before treatment predicts better therapeutic efficacy.


Assuntos
Neoplasias da Mama , Ciclofosfamida , Linfócitos T Reguladores , Humanos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/mortalidade , Idoso , Estudos Retrospectivos , Administração Oral , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Metástase Neoplásica , Resultado do Tratamento
7.
Front Plant Sci ; 15: 1301395, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38298826

RESUMO

Climate varies along geographic gradients, causing spatial variations in the effects of energy and water on species richness and the explanatory power of different climatic factors. Species of the Quercus genus are important tree species in China with high ecological and socioeconomic value. To detect whether the effects of energy and water on species richness change along climatic gradients, this study built geographically weighted regression models based on species richness and climatic data. Variation partition analysis and hierarchical partitioning analysis were used to further explore the main climatic factors shaping the richness distribution pattern of Quercus in China. The results showed that Quercus species were mainly distributed in mountainous areas of southwestern China. Both energy and water were associated with species richness, with global slopes of 0.17 and 0.14, respectively. The effects of energy and water on species richness gradually increased as energy and water in the environment decreased. The interaction between energy and water altered the effect of energy, and in arid regions, the effects of energy and water were relatively stronger. Moreover, energy explained more variation in species richness in both the entire study area (11.5%) and different climate regions (up to 19.4%). The min temperature of coldest month was the main climatic variable forming the richness distribution pattern of Quercus in China. In conclusion, cold and drought are the critical climatic factors limiting the species richness of Quercus, and climate warming will have a greater impact in arid regions. These findings are important for understanding the biogeographic characteristics of Quercus and conserving biodiversity in China.

8.
J Clin Microbiol ; 51(8): 2551-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23698535

RESUMO

To improve the rate of detection of Clonorchis sinensis infection, we compared different specimens from patients with cholecystolithiasis. Feces, gallbladder bile, and gallbladder stones collected from 179 consecutive patients with cholecystolithiasis underwent microscopic examination, and according to the results, 30 egg-positive and 30 egg-negative fecal, gallbladder bile, and gallbladder stone specimens, respectively, underwent real-time fluorescent PCR. The detection rates of eggs in feces, bile, and gallbladder stones were 30.7%, 44.7%, and 69.8%, respectively, and the differences were statistically significant (P<0.01). The PCR results confirmed that the eggs in the specimens were C. sinensis eggs. Eggs in the feces were "fresh" and in the gallbladder stones were "old." Microscopic examination of gallbladder stones may improve the detection rates of C. sinensis infection, which is important for developing individualized treatments to prevent the recurrence of gallbladder stones and to prevent the occurrence of severe liver damage and cholangiocarcinoma.


Assuntos
Cálculos/parasitologia , Técnicas de Laboratório Clínico/métodos , Clonorquíase/diagnóstico , Clonorchis sinensis/isolamento & purificação , Vesícula Biliar/parasitologia , Parasitologia/métodos , Adulto , Animais , Feminino , Humanos , Masculino , Microscopia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real
9.
Artigo em Zh | MEDLINE | ID: mdl-24818394

RESUMO

OBJECTIVE: To evaluate the prevalence of Clonorchis sinensis and bile components of gallstone patients from the Pearl River Delta region in Guangdong Province. METHODS: From June 2011 to November 2012, 406 gallstone patients from the Pearl River Delta region in Guangdong Province were enrolled in the study. Fecal specimens, bile and gallbladder stone samples were examined for the presence of C. sinensis eggs by the Kato-Katz method, centrifuged sediment smear microscopy, and triturated stone microscopy, respectively. The blood samples were detected for the antibody against C. sinensis by using colloidal gold immunochromatographic assay. Total calcium, ionized calcium, HCO3-, magnesium, pH, total bilirubin (TBIL), total bile acid (TBA), total cholesterol (CHO), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) were analyzed quantitatively in bile of gall bladder. RESULTS: The overall C. sinensis infection rate was 52.2% (212/406). The proportion of males infected with C. sinensis was 64.7% (130/201), higher than that of females (40.0%, 82/205). The content of TBIL [(1 458.0 +/- 681.0) micromol/L], CHO [(4.1 +/- 1.3) mmol/L] and magnesium [(4.8 +/- 1.8) mmol/L] in the bile from the patients under 30 years old, total calcium [(3.0 +/- 1.3) mmol/L], ionized calcium [(1.5 +/- 0.7) mmol/L], TBA [(114.6 +/- 54.5) mmol/L], CHO [(5.1 +/- 1.7) mmol/L], TBIL [(1 396.0 +/- 615.0) micromol/L], GGT [(1 562.0 +/- 583.0) U/L] and ALP [(263.0 +/- 94.0) U/L] in 31-40 years-old, or CHO [(5.4 +/- 2.2) mmol/L] in 41-50 years-old in egg-positive group was lower than that of the corresponding negative groups [(2 759.0 +/- 969.0) micromol/L, (7.5 +/- 2.5), (7.5 +/- 2.2), (3.8 +/- 1.6), (1.9 +/- 1.0), (144.1 +/- 63.4), and (9.9 +/- 2.5) mmol/L, (1 892.0 +/- 584.0) micromol/L, (2457.0 +/- 988.0) and (535.0 +/- 196.0) U/L, and (7.9 +/- 2.3) mmol/L], respectively (P < 0.05). While, the content of HCO3- [(22.7 +/- 5.1) mmol/L], pH (7.6 +/- 0.4) in 31-40 years-old group and pH (7.6 +/- 0.4) in the patients aged above 50 years-old was higher than that of the negatives [(17.3 +/- 6.9) mmol/L, 7.4 +/- 0.2, and 7.5 +/- 0.3] (P < 0.05). CONCLUSION: In the Pearl River Delta region in Guangdong Province, C. sinensis prevalence is high in the gallstone patients. There are differences in bile components between C. sinensis-infected and non-infected patients.


Assuntos
Bile/química , Clonorquíase/epidemiologia , Cálculos Biliares/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , China/epidemiologia , Clonorquíase/fisiopatologia , Clonorchis sinensis , Feminino , Cálculos Biliares/epidemiologia , Cálculos Biliares/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
10.
Infect Drug Resist ; 16: 4919-4928, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37534063

RESUMO

Purpose: This study aims to analyze the distribution of human papillomavirus (HPV) genotypes and the associations of demographic characteristics with HPV infection among women with condyloma acuminatum (CA) in Henan Province of China. Methods: From January 2019 to October 2022, 702 women with CA were sampled for HPV subtypes and surveyed by questionnaire at Henan Provincial People's Hospital. The HPV genotype was tested by flow-through hybridization after polymerase chain reaction (PCR). Results: The location of warts was mainly vulva. The age of the subjects was mainly distributed in the 20-29-year-old, followed by 30-39-year-old. The most common subtypes were HPV 6 (43.59%), 11 (24.93%), 16 (11.82%), 52 (7.83%), 58 (7.55%), 51 (7.26%), 61 (5.70%), 39 (5.56%), 18 (5.13%), and 54 (4.70%), our results also suggested that HPV 6 and 11 were the dominant genotypes in each age group. The infection of low-risk HPV (LR-HPV) (74.50%) and single HPV (47.01%) were the main categories. In terms of educational level, women with senior high school or above were inclined to infect single and pure-LR HPV. Unmarried status, sometimes or never condom use increased the chances of multiple, pure high-risk (HR) and mixed HPV infections. Women with multiple sex partners were more likely to cause multiple and mixed HPV infections. Conclusion: Our experimental data on the prevalence and subtype distribution of HPV in women with CA could provide valuable reference for preventing CA in Henan Province. The application of the nine-valent vaccine provides a broad prospect for female CA prevention.

11.
Sci Total Environ ; 903: 166260, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37579809

RESUMO

Climate change and biological invasions pose significant threats to the conservation of biodiversity and the provision of ecosystem services. With the rapid development of international trade and economy, China has become one of the countries most seriously affected by invasive alien plants (IAPs), especially the Asteraceae IAPs. For this end, we selected occurrence data of 31 Asteraceae IAPs and 33 predictor variables to explore the distribution pattern under current climate using MaxEnt model. Based on future climate data, the changes in distribution dynamics of Asteraceae IAPs were predicted under two time periods (2041-2060 and 2081-2100) and three climate change scenarios (SSP126, SSP245 and SSP585). The results indicated that the potential distribution of IAPs was mainly in the southeast of China under current climate. Climatic variables, including precipitation of coldest quarter (BIO19), temperature annual range (BIO07) and annual precipitation (BIO12) were the main factors affecting the potential distribution. Besides, human footprint (HFP), population (POP) and soil moisture (SM) also had a great contribution for shaping the distribution pattern. With climate change, the potential distribution of IAPs would shift to the northwest and expand. It would also accelerate the expansion of most Asteraceae IAPs in China. The results of our study can help to understand the dynamics change of distributions of Asteraceae IAPs under climate change in advance so that early strategies can be developed to reduce the risk and influence of biological invasions.

12.
Front Oncol ; 13: 1234847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37799460

RESUMO

Objective: Autoantibodies have been reported to be associated with cancers. As a biomarker, autoantibodies have been widely used in the early screening of lung cancer. However, the correlation between autoantibodies and the prognosis of lung cancer patients is poorly understood, especially in the Asian population. This retrospective study investigated the association between the presence of autoantibodies and outcomes in patients with lung cancer. Methods: A total of 264 patients diagnosed with lung cancer were tested for autoantibodies in Henan Provincial People's Hospital from January 2017 to June 2022. The general clinical data of these patients were collected, and after screening out those who met the exclusion criteria, 151 patients were finally included in the study. The Cox proportional hazards model was used to analyze the effect of autoantibodies on the outcomes of patients with lung cancer. The Kaplan-Meier curve was used to analyze the relationship between autoantibodies and the overall survival of patients with lung cancer. Results: Compared to lung cancer patients without autoantibodies, those with autoantibodies had an associated reduced risk of death (HRs: 0.45, 95% CIs 0.27~0.77), independent of gender, age, smoking history, pathological type, and pathological stage of lung cancer. Additionally, the association was found to be more significant by subgroup analysis in male patients, younger patients, and patients with small cell lung cancer. Furthermore, lung cancer patients with autoantibodies had significantly longer survival time than those without autoantibodies. Conclusion: The presence of autoantibodies is an independent indicator of good prognosis in patients with lung cancer, providing a new biomarker for prognostic evaluation in patients with lung cancer.

13.
Front Oncol ; 13: 1353702, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38192623

RESUMO

[This corrects the article DOI: 10.3389/fonc.2023.1234847.].

14.
Sci Total Environ ; 860: 160548, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36455727

RESUMO

A better understanding of the underlying ecological mechanisms of diversity-biomass relationships in forest layers (i.e., overstory and understory) is critical to understand the importance of vertical stratification to the functioning of forest ecosystems. However, it is not clear how multiple abiotic (i.e., climate and geography) and biological (i.e., biodiversity, functional characteristics, and stand structural complexity) factors simultaneously determine the aboveground biomass (AGB) of each individual forest stratum. We used data on 156,270 trees from 1986 plots in North China to explore the relationships among biological diversity, plant functional traits, stand structure, climate and topography on variation in AGB of each stratum. The results showed that different biological factors determined the AGB of overstory and understory, and thus indicating different underlying ecological mechanisms in temperate forests. The effects of forest biodiversity on AGB were only significant in understory stratum. In the overstory of the forest, forests with high tree-size dimension inequality and high dominant tree height had larger AGB, hence mass ratio effect and stand structure complexity were the main ecological mechanisms for high biomass. In understory, diversity and overstory attributes were the main factors affecting biomass. Tree height and AGB of the overstory reduced the AGB of the understory layer. In consequence overstory attributes and niche complementation were the main ecological mechanisms in the understory. The overstory exerted influence on the understory through resource quantity and resource heterogeneity. Our findings have important implications for carbon management, enhancement of forest functions and sustainable forest management in temperate forests.


Assuntos
Ecossistema , Florestas , Biomassa , Árvores , Biodiversidade , China
15.
Tree Physiol ; 43(5): 737-750, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-36708029

RESUMO

Ongoing global climate change is increasing the risk of drought stress in some areas, which may compromise forest health. Such drought events also increase outbreaks of insect herbivores, resulting in plant defoliation. Interactions between drought and defoliation are poorly understood. In a greenhouse experiment, we selected a native species, Quercus acutissima Carr. and an alien species, Quercus rubra L. to explore their physiological responses to drought and defoliation treatments. After the treatments, we determined the seedlings' physiological responses on Days 10 and 60. Our results showed that the defoliation treatment accelerated the carbon reserve consumption of plants under drought stress and inhibited the growth of both seedling types. Under the drought condition, Q. rubra maintained normal stem-specific hydraulic conductivity and normal growth parameters during the early stage of stress, whereas Q. acutissima used less water and grew more slowly during the experiment. Sixty days after defoliation treatment, the stem starch concentration of Q. acutissima was higher than that of the control group, but the stem biomass was lower. This indicates that Q. acutissima adopted a 'slow strategy' after stress, and more resources were used for storage rather than growth, which was conducive to the ability of these seedlings to resist recurrent biotic attack. Thus, Q. acutissima may be more tolerant to drought and defoliation than Q. rubra. The resource acquisition strategies of Quercus in this study suggest that the native Quercus species may be more successful at a long-term resource-poor site than the alien Quercus species.


Assuntos
Quercus , Plântula , Plântula/fisiologia , Quercus/fisiologia , Secas , Água/fisiologia , Florestas , Folhas de Planta/fisiologia
16.
Front Plant Sci ; 14: 1140080, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484465

RESUMO

The increase of nitrogen (N) deposition and the diversity of its components lead to significant changes in the structure and function of temperate meadow steppe, which could affect plant nutrient uptake, nutrient resorption and litter decomposition, thus affecting the biogeochemical cycle process. The distribution and metabolism of nitrogen and phosphorus in plants determine the growth process and productivity of plants. Plant nutrient uptake, nutrient resorption and litter decomposition play an important role in the nutrient cycling process of ecosystem. This study closely combined these three processes to carry out experiments with different nitrogen dosages and types, and systematically explored the response of nitrogen and phosphorus nutrient cycling to nitrogen deposition. The results showed that nitrogen deposition can greatly affect ecosystem nutrient cycle of nitrogen and phosphorus. Firstly, Nitrogen deposition has significant effect on plant nutrient uptake. Nitrogen uptake of stems and leaves increased with the increase of nitrogen addition dosage, while phosphorus uptake of stems and leaves showed a downward trend or no significant effect. Besides, nitrogen addition type had a significant effect on nitrogen and phosphorus content of stems. Secondly, Nitrogen addition dosage had a significant effect on plant nutrient resorption, while nitrogen addition type had no significant effect on it. Thirdly, nitrogen deposition has significant effect on litter decomposition. With the increase of nitrogen addition dosage, the initial nitrogen content of litters increased and the decomposition rate of litters accelerated. Nitrogen application type had significant effect on stem litter decomposition. These results indicated that nitrogen deposition significantly affects plant nutrient cycling, and thus affects the structure and function of grassland ecosystem.

17.
Nat Commun ; 14(1): 592, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737606

RESUMO

The great challenge for the growth of non-centrosymmetric 2D single crystals is to break the equivalence of antiparallel grains. Even though this pursuit has been partially achieved in boron nitride and transition metal dichalcogenides (TMDs) growth, the key factors that determine the epitaxy of non-centrosymmetric 2D single crystals are still unclear. Here we report a universal methodology for the epitaxy of non-centrosymmetric 2D metal dichalcogenides enabled by accurate time sequence control of the simultaneous formation of grain nuclei and substrate steps. With this methodology, we have demonstrated the epitaxy of unidirectionally aligned MoS2 grains on a, c, m, n, r and v plane Al2O3 as well as MgO and TiO2 substrates. This approach is also applicable to many TMDs, such as WS2, NbS2, MoSe2, WSe2 and NbSe2. This study reveals a robust mechanism for the growth of various 2D single crystals and thus paves the way for their potential applications.

18.
Front Plant Sci ; 14: 1158221, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342129

RESUMO

Introduction: It is of great significance to understand the characteristics and influencing factors of vegetation coverage variation in the warm temperate zone. As a typical region of the warm temperate zone in eastern China, the mountainous and hilly region in central-south Shandong Province has fragile ecological environment and soil erosion problem. Studying on vegetation dynamics and its influencing factors in this region will help to better understand the relationship between climate change and vegetation cover change in the warm temperate zone of eastern China, and the influence of human activities on vegetation cover dynamics. Methods: Based on dendrochronology, a standard tree-ring width chronology was established in the mountainous and hilly region of central-south Shandong Province, and the vegetation coverage from 1905 to 2020 was reconstructed to reveal the dynamic change characteristics of vegetation cover in this region. Secondly, the influence of climate factors and human activities on the dynamic change of vegetation cover was discussed through correlation analysis and residual analysis. Results and discussion: In the reconstructed sequence, 23 years had high vegetation coverage and 15 years had low vegetation coverage. After low-pass filtering, the vegetation coverage of 1911-1913, 1945-1951, 1958-1962, 1994-1996, and 2007-2011 was relatively high, while the vegetation coverage of 1925-1927, 1936-1942, 2001-2003, and 2019-2020 was relatively low. Although precipitation determined the variation of vegetation coverage in this study area, the impacts of human activities on the change of vegetation coverage in the past decades cannot be ignored. With the development of social economy and the acceleration of urbanization, the vegetation coverage declined. Since the beginning of the 21st century, ecological projects such as Grain-for-Green have increased the vegetation coverage.

19.
Parasitol Res ; 111(4): 1497-503, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22669695

RESUMO

High prevalence of cholecystolithiasis in parts of East Asia has been postulated to be associated with Clonorchis sinensis infection. This study describes the development of a TaqMan-based real-time PCR assay for the detection of C. sinensis DNA in gallbladder bile and stone samples from patients with cholecystolithiasis. Primers and probe targeting the cytochrome c oxidase subunit 1 gene of mitochondrial DNA proved to be highly specific for C. sinensis and did not amplify other related heterogeneous DNA samples. The detection limit of this assay was 0.1 pg of adult C. sinensis genomic DNA. All of the egg-positive samples determined by microscopy yielded positive results by real-time PCR assay and that genetic testing of gallbladder stones using real-time PCR was considered as the most effective means for assessing C. sinensis infection status. This assay not only contributes to a greater understanding of stone pathogenesis but also benefits patients with cholecystolithiasis by facilitating effective diagnosis, treatment, and relapse prevention.


Assuntos
Bile/parasitologia , Colecistolitíase/complicações , Clonorquíase/diagnóstico , Clonorchis sinensis/isolamento & purificação , DNA de Helmintos/isolamento & purificação , Vesícula Biliar/parasitologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto , Animais , Ásia , Clonorquíase/parasitologia , Clonorchis sinensis/genética , Primers do DNA/genética , DNA de Helmintos/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/métodos , Sondas de Oligonucleotídeos/genética , Parasitologia/métodos , Sensibilidade e Especificidade
20.
Pathol Oncol Res ; 28: 1610446, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755416

RESUMO

Circular RNA (circRNA) is stable and abundant in exosomes as a potential biomarker for the diagnosis and prognosis of tumor. In this study, cancer specific exosomal circRNAs were identified through circRNA microarray, and 58 circRNAs were significantly upregulated in cancer cells derived exosomes. Then 60 patients with newly diagnosed gastric cancer (GC), 30 chronic gastritis patients and 30 healthy subjects were enrolled for further clinical validation. We detected that hsa_circ_0015286 was remarkably highly expressed in GC tissue, plasma and cancer cells compared with normal controls. Results of ROC curve analysis showed that the area under curve (AUC) of hsa_circ_0015286, CEA and CA 19-9 was 0.778, 0.673, and 0.665, respectively. The combined detection of three indicators had the highest AUC (0.843). Exosomal hsa_circ_0015286 expression was closely associated with tumor size, TNM stage and lymph node metastasis. The expression level of exosomal hsa_circ_0015286 in GC patients decreased significantly after surgery. Overall survival of patients with low hsa_circ_0015286 expression was longer than those with high expression. Our data demonstrated that exosomal hsa_circ_0015286 might be a promising noninvasive biomarker for the diagnosis and prognosis evaluation of GC.


Assuntos
Neoplasias Gástricas , Biomarcadores Tumorais/metabolismo , Humanos , Prognóstico , RNA Circular/genética , Curva ROC , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
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