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1.
Apoptosis ; 29(3-4): 412-423, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38001343

RESUMO

Ferroptosis, a nonapoptotic form of cell death marked by iron-dependent peroxidation of phospholipids, is associated with the occurrence and progression of tumors. Erastin, a selective inhibitor of the cystine/glutamate transporter system Xc-, can induce the ferroptosis of cancer cells. Multiple myeloma (MM) has been reported to be insensitive to erastin-induced ferroptosis. However, we found the erastin sensitivity of different MM cells varied widely. Specifically, SLC7A11 abundance determined the sensitivity of MM cells to erastin-induced ferroptosis. MM cells expressing a high SLC7A11 level were more sensitive to erastin-induced ferroptosis than cells expressing a low level of SLC7A11. Moreover, the expression of SLC7A11 gradually increased with the progression of plasma cell dyscrasias. Survival analysis indicated that high levels of SLC7A11 predicted a poor prognosis for MM patients. Knocking down SLC7A11 expression significantly inhibited the proliferation of MM cells and induced ferroptotic cell death. Additionally, we revealed that the long noncoding RNA (lncRNA) SLC7A11-AS1 was a critical regulatory factor of SLC7A11 expression. SLC7A11-AS1 overexpression diminished SLC7A11 levels, leading to the ferroptosis of MM cells. In summary, our data show that heterogeneous SLC7A11 expression affects MM cell sensitivity to ferroptosis, providing a theoretical basis for improving the clinical treatment of MM.


Assuntos
Ferroptose , Mieloma Múltiplo , Piperazinas , Humanos , Apoptose/genética , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Ferroptose/genética , Morte Celular , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/metabolismo
2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(6): 758-760, 2024 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-38818565

RESUMO

Char syndrome is a rare autosomal dominant genetic disorder characterized by patent ductus arteriosus, facial dysmorphism, and dysplasia of fingers/toes. It may also be associated with multiple papillae, dental dysplasia, and sleep disorders. TFAP2B has proven to be a pathogenic gene for neural crest derivation and development, and several variants of this gene have been identified. Bone morphogenetic protein signaling plays an important role in embryonic development by participating in limb growth and patterning, and regulation of neural crest cell development. TFAP2B is an upstream regulatory gene for bone morphogenetic proteins 2 and 4. Variants of the TFAP2B gene may lead to abnormal proliferation of neural crest cells by affecting the expression of bone morphogenetic proteins, resulting in multiple organ dysplasia syndrome. In addition, TFAP2B variants may only lead to patent ductus arteriosus instead of typical Char syndrome.


Assuntos
Permeabilidade do Canal Arterial , Humanos , Permeabilidade do Canal Arterial/genética , Fator de Transcrição AP-2/genética , Anormalidades Múltiplas/genética , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Crista Neural/metabolismo , Crista Neural/embriologia , Face/anormalidades , Dedos/anormalidades
3.
J Med Internet Res ; 25: e44186, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37191983

RESUMO

BACKGROUND: Chickenpox is an old but easily neglected infectious disease. Although chickenpox is preventable by vaccines, vaccine breakthroughs often occur, and the chickenpox epidemic is on the rise. Chickenpox is not included in the list of regulated communicable diseases that must be reported and controlled by public and health departments; therefore, it is crucial to rapidly identify and report varicella outbreaks during the early stages. The Baidu index (BDI) can supplement the traditional surveillance system for infectious diseases, such as brucellosis and dengue, in China. The number of reported chickenpox cases and internet search data also showed a similar trend. BDI can be a useful tool to display the outbreak of infectious diseases. OBJECTIVE: This study aimed to develop an efficient disease surveillance method that uses BDI to assist in traditional surveillance. METHODS: Chickenpox incidence data (weekly from January 2017 to June 2021) reported by the Yunnan Province Center for Disease Control and Prevention were obtained to evaluate the relationship between the incidence of chickenpox and BDI. We applied a support vector machine regression (SVR) model and a multiple regression prediction model with BDI to predict the incidence of chickenpox. In addition, we used the SVR model to predict the number of chickenpox cases from June 2021 to the first week of April 2022. RESULTS: The analysis showed that there was a close correlation between the weekly number of newly diagnosed cases and the BDI. In the search terms we collected, the highest Spearman correlation coefficient was 0.747. Most BDI search terms, such as "chickenpox," "chickenpox treatment," "treatment of chickenpox," "chickenpox symptoms," and "chickenpox virus," trend consistently. Some BDI search terms, such as "chickenpox pictures," "symptoms of chickenpox," "chickenpox vaccine," and "is chickenpox vaccine necessary," appeared earlier than the trend of "chickenpox virus." The 2 models were compared, the SVR model performed better in all the applied measurements: fitting effect, R2=0.9108, root mean square error (RMSE)=96.2995, and mean absolute error (MAE)=73.3988; and prediction effect, R2=0.548, RMSE=189.1807, and MAE=147.5412. In addition, we applied the SVR model to predict the number of reported cases weekly in Yunnan from June 2021 to April 2022 using the same period of the BDI. The results showed that the fluctuation of the time series from July 2021 to April 2022 was similar to that of the last year and a half with no change in the level of prevention and control. CONCLUSIONS: These findings indicated that the BDI in Yunnan Province can predict the incidence of chickenpox in the same period. Thus, the BDI is a useful tool for monitoring the chickenpox epidemic and for complementing traditional monitoring systems.


Assuntos
Varicela , Humanos , Varicela/epidemiologia , Varicela/prevenção & controle , Vacina contra Varicela , China/epidemiologia , Surtos de Doenças/prevenção & controle , Incidência , Infodemiologia , Máquina de Vetores de Suporte , Vigilância de Evento Sentinela
4.
Proc Natl Acad Sci U S A ; 116(51): 25491-25496, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31792172

RESUMO

Water bodies (WBs), such as lakes, ponds, and impoundments, provide essential ecosystem services for human society, yet their characteristics and changes over large areas remain elusive. Here we used unprecedented data layers derived from all Landsat images available between 1984 and 2015 to understand the overall characteristics and changes of WBs between 2 epochs (i.e., 1984 to 1999 and 2000 to 2015) in China. Results show that the abundance estimate of WBs greater than 1 km2 and the total WB surface area were 0.3 to 1.5 times and 0.2 to 0.5 times more than the previous estimates, respectively. The size-abundance and shoreline-area relationships of WBs in China conformed to the classic power scaling law, in contradiction to most previous studies. WB changes with various occurrence probabilities show widespread coexistence of disappearance of existent and emergence of new WBs across China driven primarily by human activities and climate change. Our results highlight the importance of using appropriate long-term satellite data to reveal the true properties and dynamics of WBs over large areas, which is essential for developing scaling theories and understanding the relative impacts of human activities and climate change on water resources in the world.

5.
BMC Plant Biol ; 21(1): 222, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001008

RESUMO

BACKGROUND: Leaf length and width could be a functioning relationship naturally as plant designs. Single-vein leaves have the simplest symmetrical distribution and structural design, which means that fast-growing single-vein species could interpret the scheme more efficiently. The distribution of leaf length and width can be modulated for better adaptation, providing an informative perspective on the various operational strategies in an emergency, while this mechanism is less clear. Here we selected six age groups of Cunninghamia lanceolata pure forests, including saplings, juveniles, mature, and old-growth trees. We pioneered a tapering model to describe half-leaf symmetric distribution with mathematical approximation based on every measured leaf along developmental sequence, and evaluated the ratio of leaf basal part length to total length (called tipping leaf length ratio). RESULTS: The tipping leaf length ratio varied among different tree ages. That means the changes of tipping leaf length ratio and leaf shape are a significant but less-noticed reflection of trees tradeoff strategies at different growth stages. For instance, there exhibited relatively low ratio during sapling and juvenile, then increased with increasing age, showing the highest value in their maturity, and finally decreased on mature to old-growth transition. The tipping leaf length ratio serves as a cost-benefit ratio, thus the subtle changes in the leaf symmetrical distribution within individuals reveal buffering strategy, indicating the selection for efficient design of growth and hydraulic in their developmental sequences. CONCLUSIONS: Our model provides a physical explanation of varied signatures for tree operations in hydraulic buffering through growth stages, and the buffering strategy revealed from leaf distribution morphologically provides evidence on the regulation mechanism of leaf biomechanics, hydraulics and physiologies. Our insight contributes greatly to plant trait modeling, policy and management, and will be of interest to some scientists and policy makers who are involved in climate change, ecology and environment protection, as well as forest ecology and management.


Assuntos
Cunninghamia/crescimento & desenvolvimento , Cunninghamia/genética , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/genética , Árvores/crescimento & desenvolvimento , Árvores/genética , Fatores Etários , Florestas , Modelos Teóricos
7.
Ecol Appl ; 28(6): 1655-1668, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29869352

RESUMO

Most of the planet's population currently lives in urban areas, and urban land expansion is one of the most dramatic forms of land conversion. Understanding how cities evolve temporally, spatially, and organizationally in a rapidly urbanizing world is critical for sustainable development. However, few studies have examined the coevolution of urban attributes in time and space simultaneously and the adequacy of power law scaling across cities and through time, particularly in countries that have experienced abrupt, widespread, political and economic changes. Here, we show the temporal coevolution of multiple physical, demographic, socioeconomic, and environmental attributes in individual cities, and the cross-city scaling of urban attributes at six time points (i.e., 1978, 1990, 1995, 2000, 2005, and 2010) in 32 major Chinese cities. We found that power law scaling could adequately characterize both the cross-city scaling of urban attributes across cities and the longitudinal scaling describing the temporal coevolution of urban attributes within individual cities. The cross-city scaling properties demonstrated substantial changes over time signifying evolved social and economic forces. A key finding was that the cross-city linear or superlinear scaling of urban area with population contradicts the theoretical sublinear power law scaling proposed between infrastructure and population. Furthermore, the cross-city scaling between area and population transitioned from linear to superlinear over time, and the superlinear scaling in recent times suggests decreased infrastructure efficiency. Our results demonstrate a diseconomy of scale in urban areal expansion that indicates a significant waste of land resources in the urbanization process. Future planning efforts should focus on policies that increase urban land use efficiency before continuing expansion.


Assuntos
Urbanização , China , Cidades , Análise Espacial
9.
Front Med ; 18(1): 180-191, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37776435

RESUMO

Lipin proteins including Lipin 1-3 act as transcriptional co-activators and phosphatidic acid phosphohydrolase enzymes, which play crucial roles in lipid metabolism. However, little is known about the function of Lipin3 in triglyceride (TG) metabolism. Here, we identified a novel mutation (NM_001301860: p.1835A>T/p.D612V) of Lipin3 in a large family with hypertriglyceridemia (HTG) and obesity through whole-exome sequencing and Sanger sequencing. Functional studies revealed that the novel variant altered the half-life and stability of the Lipin3 protein. Hence, we generated Lipin3 heterozygous knockout (Lipin3-heKO) mice and cultured primary hepatocytes to explore the pathophysiological roles of Lipin3 in TG metabolism. We found that Lipin3-heKO mice exhibited obvious obesity, HTG, and non-alcoholic fatty liver disorder. Mechanistic study demonstrated that the haploinsufficiency of Lipin3 in primary hepatocytes may induce the overexpression and abnormal distribution of Lipin1 in cytosol and nucleoplasm. The increased expression of Lipin1 in cytosol may contribute to TG anabolism, and the decreased Lipin1 in nucleoplasm can reduce PGC1α, further leading to mitochondrial dysfunction and reduced TG catabolism. Our study suggested that Lipin3 was a novel disease-causing gene inducing obesity and HTG. We also established a relationship between Lipin3 and mitochondrial dysfunction.

10.
Int Immunopharmacol ; 130: 111754, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38428147

RESUMO

Acute kidney injury (AKI) is a complex disease, with macrophages playing a vital role in its progression. However, the mechanism of macrophage function remains unclear and strategies targeting macrophages in AKI are controversial. To address this issue, we used single-cell RNA-seq analysis to identify macrophage sub-types involved in ischemia-reperfusion-induced AKI, and then screened for associated hub genes using intersecting bulk RNA-seq data. The single-cell and bulk RNA-seq datasets were obtained from the Gene Expression Omnibus (GEO) database. Screening of differentially-expressed genes (DEGs) and pseudo-bulk DEG analyses were used to identify common hub genes. Pseudotime and trajectory analyses were performed to investigate the progression of cell differentiation. CellChat analysis was performed to reveal the crosstalk between cell clusters. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were used to identify enriched pathways in the cell clusters. Immunofluorescence and RT-PCR were preformed to validate the expression of the identified hub genes. Four hub genes, Vim, S100a6, Ier3, and Ccr1, were identified in the infiltrated macrophages between normal samples and those 3 days after ischemia-reperfusion renal injury (IRI); all were associated with the progression of IRI-induced AKI. Increased expression of Vim, S100a6, Ier3, and Ccr1 in infiltrated macrophages may be associated with inflammatory responses and may mediate crosstalk between macrophages and renal tubular epithelial cells under IRI conditions. Our results reveal that Ier3 may be critical in AKI, and that Vim, S100a6, Ier3, and Ccr1 may act as novel biomarkers and potential therapeutic targets for IRI-induced AKI.


Assuntos
Injúria Renal Aguda , Traumatismo por Reperfusão , Humanos , RNA-Seq , Análise da Expressão Gênica de Célula Única , Injúria Renal Aguda/genética , Traumatismo por Reperfusão/genética , Rim , Macrófagos , Isquemia
11.
Blood Adv ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38875465

RESUMO

Exosomes have emerged as promising vehicles for delivering therapeutic cargoes to specific cells or tissues, owing to their superior biocompatibility, reduced immunogenicity, and enhanced targeting capabilities compared to conventional drug delivery systems. In this study, we developed a delivery platform utilizing exosomes derived from monocytes, specifically designed for targeted delivery of Bortezomib (Btz) to multiple myeloma (MM) cells. Our approach involved the genetic modification of monocytes to express antibodies targeting B cell maturation antigen (anti-BCMA), as BCMA selectively expresses on myeloma cells. This modified anti-BCMA was then efficiently incorporated into the monocyte-derived exosomes. These adapted exosomes effectively encapsulated Bortezomib, leading to enhanced drug accessibility within MM cells and sustained intracellular accumulation over an extended period. Remarkably, our results demonstrated that anti-BCMA-Exo-Btz outperformed free Btz in vitro, exhibiting a more potent myeloma-suppressive effect. In orthotopic MM xenograft models, anti-BCMA-Exo-Btz exhibited a significant anti-tumor effect compared to free Btz. Furthermore, it demonstrated remarkable specificity in targeting Bortezomib to myeloma cells in vivo. Importantly, we observed no significant histological damage in mice treated with anti-BCMA-Exo-Btz and a slight effect on PBMCs. Additionally, our study highlighted the multifunctional potential of monocyte-exosomes, which induced cell apoptosis, mediated immune responses, and enhanced the osteogenic potential of mesenchymal stromal cells. In conclusion, our study suggests that exosomes modified with targeting ligands hold therapeutic promise for delivering Bortezomib to myelomas, offering substantial potential for clinical applications.

12.
DNA Cell Biol ; 43(7): 325-330, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38700464

RESUMO

Megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome (MPPH), a type of overgrowth syndrome, is characterized by progressive megalencephaly, cortical brain malformations, and distal limb anomalies. Previous studies have revealed that the overactivity of the phosphatidylinositol 3-kinase-Protein kinase B pathway and the increased cyclin D2 (CCND2) expression were the main factors contributing to this disease. Here, we present the case of a patient who exhibited megalencephaly, polymicrogyria, abnormal neuronal migration, and developmental delay. Serum tandem mass spectrometry and chromosome examination did not detect any metabolic abnormalities or copy number variants. However, whole-exome sequencing and Sanger sequencing revealed a de novo nonsense mutation (NM_001759.3: c.829C>T; p.Gln277X) in the CCND2 gene of the patient. Bioinformatics analysis predicted that this mutation may disrupt the structure and surface charge of the CCND2 protein. This disruption could potentially prevent polyubiquitination of CCND2, leading to its resistance against degradation. Consequently, this could drive cell division and growth by altering the activity of key cell cycle regulatory nodes, ultimately contributing to the development of MPPH. This study not only presents a new case of MPPH and expands the mutation spectrum of CCND2 but also enhances our understanding of the mechanisms connecting CCND2 with overgrowth syndromes.


Assuntos
Ciclina D2 , Megalencefalia , Polidactilia , Polimicrogiria , Feminino , Humanos , Masculino , Códon sem Sentido/genética , Ciclina D2/genética , Sequenciamento do Exoma , Hidrocefalia , Malformações do Desenvolvimento Cortical , Megalencefalia/genética , Megalencefalia/diagnóstico , Polidactilia/genética , Polidactilia/diagnóstico , Polimicrogiria/genética , Polimicrogiria/diagnóstico , Pré-Escolar
13.
Front Neurol ; 15: 1319962, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481944

RESUMO

This report presents a case of Charcot-Marie-Tooth dominant intermediate D (CMTDID), a rare subtype of Charcot-Marie-Tooth disease, in a 52 years-old male patient. The patient exhibited mobility impairment, foot abnormalities (pes cavus), and calf muscle atrophy. Whole exome sequencing and Sanger sequencing suggested that a novel variant (NM_000530.8, c.145C>A/p.His49Asn) of MPZ may be the genetic lesion in the patient. The bioinformatic program predicted that the new variant (p.His49Asn), located at an evolutionarily conserved site of MPZ, was neutral. Our study expands the variant spectrum of MPZ and the number of identified CMTDID patients, contributing to a better understanding of the relationship between MPZ and CMTDID.

14.
Emerg Microbes Infect ; 12(1): 2185464, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36849445

RESUMO

Balancing the potentially serious outcomes of asymptomatic brucellosis and "waiting" for treatment in clinical practice is an urgent issue. Therefore, we assessed the follow-up outcomes and epidemiological characteristics of asymptomatic brucellosis in the absence of treatment to provide evidence-based clinical clues. We searched eight databases in which 3610 studies from 1990 to 2021 were related to the follow-up outcomes of asymptomatic brucellosis. Thirteen studies, involving 107 cases, were finally included. Regarding the follow-up outcomes, we examined the presence or absence of symptoms and decreased serum agglutination test (SAT) titre. During the 0.5-18 months follow-up period, the pooled prevalence of appearing symptomatic was 15.4% (95% CI 2.1%-34.3%), cases that remained asymptomatic were 40.3% (95% CI 16.6%-65.8%), and decreased SAT titre was observed in 36.5% (95% CI 11.6%-66.1%). Subgroup analysis indicated that the pooled prevalence of appearing symptomatic with follow-up times of less than 6 months, 6-12 months, and 12-18 months was 11.5%, 26.4%, and 47.6%, respectively. The student subgroup had a higher prevalence of symptoms (46.6%) than the occupational and family populations. In conclusion, asymptomatic brucellosis has a high likelihood of appearing symptomatic and its severity may be underestimated. Active screening of occupational and family populations should be enhanced, and special attention should be paid to high-titre students for early intervention, if necessary. Additionally, future prospective, long-term, and large-sample follow-up studies are essential.


Assuntos
Brucelose , Humanos , Seguimentos , Brucelose/epidemiologia , Testes de Aglutinação , Prevalência
15.
PLoS Negl Trop Dis ; 17(9): e0011590, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37708094

RESUMO

BACKGROUND: The treatment of brucellosis suffers from a high recurrence rate and drug resistance. Our study researched the differences in efficacy and side effects between triple antibiotics therapy and dual antibiotics therapy in the treatment of brucellosis through a systematic review and meta-analysis. METHODS: We searched 4 English electronic databases and 2 Chinese electronic databases for randomized controlled trials and cohort studies published through September 2022 on the use of triple antibiotics versus dual antibiotics in the treatment of brucellosis. Overall outcome indicators were therapeutic failure rate, relapse rate, overall therapeutic failure rate, and side effect rate. Relative risk (RR) and 95% confidence intervals (95% CIs) were used as summary statistics. A fixed-effects model was used to combine the overall effect sizes. RESULTS: The meta-analysis included 15 studies consisting of 11 randomized controlled trials and 4 cohort studies. Triple antibiotics showed better efficacy than dual antibiotics in a comparison of 3 overall outcome indicators (therapeutic failure rate (RR 0.42; 95% CI 0.30 to 0.59 heterogeneity P = 0.29, I2 = 15%), relapse rate (RR 0.29; 95% CI 0.18 to 0.45 heterogeneity P = 0.88, I2 = 0%), and overall therapeutic failure rate (RR 0.37; 95% CI 0.28 to 0.48 heterogeneity P = 0.35, I2 = 9%)). The incidence of side effects in patients with brucellosis treated with triple antibiotics was not significantly different from that in brucellosis patients treated with dual antibiotics (RR 0.85; 95% CI 0.67 to 1.06 heterogeneity P = 0.1, I2 = 35%). Sensitivity analyses showed robust results and Peter's test showed no publication bias. The results of subgroup analyses for the research type, drugs, and type of brucellosis were largely consistent with the overall outcome indicators, indicating the reliability and robustness of the overall results. CONCLUSIONS: In the treatment of brucellosis, triple antibiotics have better efficacy than dual antibiotics and do not increase the incidence of side effects.


Assuntos
Brucelose , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Reprodutibilidade dos Testes , Antibacterianos/efeitos adversos , Polimixina B , Brucelose/tratamento farmacológico
16.
Environ Sci Pollut Res Int ; 30(55): 117817-117828, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37874521

RESUMO

This multicenter study aimed to investigate the relationship between varicella incidence and meteorological factors including mean temperature, relative humidity, sunshine duration, diurnal temperature difference, wind speed, and rainfall, as previous studies have produced varying results. Our study also sought to identify potential sources of heterogeneity. Data on reported daily varicella numbers and meteorological factors were collected for 14 cities in Yunnan Province from 2017 to 2021. A distribution-lagged nonlinear model was constructed to explore the relationship between meteorological conditions and varicella incidence in each included city. We then used multiple meta-regression to explore sources of heterogeneity using demographic economics indicators, air pollutants, and geographic location as potential modifiers. The cumulative hazard effect plot showed an inverted S-shape for the relationship between temperature and varicella, with the smallest RR (relative risk) (0.533, 95% CI: 0.401-0.708) at temperatures up to 27.2 °C. The maximum RR (1.171, 95% CI: 1.001-1.371) was obtained when the relative humidity was equal to 98.5%. The RR (1.164, 95% CI: 1.002-1.352) was greatest at a diurnal temperature range of 2 °C (1.164, 95% CI: 1.002-1.352) and least (0.913, 95% CI: 0.834-0.999) at a diurnal temperature range of 16.1 °C. The maximum RR (1.214, 95% CI: 1.089-1.354) was obtained at 0 h of sunshine, and the minimum RR (0.808, 95% CI: 0.675-0.968) was obtained at 12.4 h of sunshine. The RR (0.792, 95% CI: 0.633-0.992) was minimum at a wind velocity of 4.8 m/s. Residual heterogeneity ranged from 1 to 42.7%, with PM10 (particles with an aerodynamic diameter less than 10 µm), GDP (gross domestic product), and population density explaining some of this heterogeneity. The temperature has a dual effect on varicella incidence. Varicella cases are negatively correlated with diurnal temperature range, sunshine duration, and wind speed, and positively correlated with relative humidity. GDP and PM10 may have a significant role in altering the association between temperature and varicella, while PM10 and population density may alter the association between wind velocity and varicella.


Assuntos
Varicela , Humanos , China/epidemiologia , Conceitos Meteorológicos , Temperatura , Incidência
17.
Ying Yong Sheng Tai Xue Bao ; 33(2): 467-476, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35229521

RESUMO

To assess the high-resolution digital soil mapping method for small watersheds in hilly areas, we explored the role of landscape classification and multiscale micro-landform features in predicting soil pH, soil clay content (SCC), and cation exchange capacity (CEC). Geomorphons (GM) terrain classification method was used to create landform units. The traditional digital elevation model (DEM) derivatives and remote sensing variables were employed for different combinations with landscape and micro-landform classification variables, with further compa-rison and analysis being conducted. In addition, three machine learning techniques, including support vector machine (SVM), partial least squares regression (PLSR), and random forest (RF), were used to build prediction models. The best method was then selected, and then combined with regression kriging by modeling spatial structure of the model residuals. The results showed that the application of landscape and multiscale micro-landform classification variables effectively improved the prediction accuracy of pH, SCC, and CEC by 18.8%, 8.2% and 8.7%, respectively. The map of landscape classification that contained vegetation coverage information had greater model contribution than land use data. The GM classification map with 5 m resolution was more suitable for high-precision DSM than those with lower resolution. The composite model of RF performed the best in predicting SCC, while the pH and CEC were not suitable for adding the residual regression kriging on the basis of RF model. Finally, the combination of landscape and multiscale micro-landform classification variables, DEM derivatives and remote sensing variables had the highest prediction accuracy for all the three soil properties. This result indicated that multivariable contained more effective soil information than single data source for rolling areas. The landscape variables composed of GM and surface classified data explained about 40% of the spatial variation of tested soil attributes in hilly area. Therefore, multi-resolution GM and landscape classified variables could be included into the construction of prediction model in research of soil mapping.


Assuntos
Aprendizado de Máquina , Solo , Análise dos Mínimos Quadrados , Solo/química , Análise Espacial
18.
J Int Med Res ; 49(5): 3000605211018426, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34057843

RESUMO

Myelodysplastic/myeloproliferative neoplasms (MDS/MPNs) are a heterogeneous group of hematologic malignancies characterized by dysplastic and myeloproliferative overlapping features in the bone marrow and blood. The occurrence of the disease is related to age, prior history of MPN or MDS, and recent cytotoxic or growth factor therapy, but it rarely develops after acute myeloid leukemia (AML). We report a rare case of a patient diagnosed with AML with t(8; 21)(q22; q22) who received systematic chemotherapy. After 4 years of follow-up, MDS/MPN-unclassifiable occurred without signs of primary AML recurrence.


Assuntos
Neoplasias Hematológicas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Doenças Mieloproliferativas-Mielodisplásicas , Medula Óssea , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico
19.
Sci Total Environ ; 771: 145381, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33548722

RESUMO

Higher land surface temperature (LST) in cities than its surrounding areas presents a major sustainability challenge for cities. Adaptation and mitigation of the increased LST require in-depth understanding of the impacts of landscape features on LST. We studied the influences of different landscape features on LST in five large cities across China to investigate how the features of a specific urban landscape (endogenous features), and neighboring environments (exogenous features) impact its LST across a continuum of spatial scales. Surprisingly, results show that the influence of endogenous landscape features (Eendo) on LST can be described consistently across all cities as a nonlinear function of grain size (gs) and neighbor size (ns) (Eendo = ßnsgs-0.5, where ß is a city-specific constant) while the influence of exogenous features (Eexo) depends only on neighbor size (ns) (Eexo = Î³-εns0.5, where γ and ε are city-specific constants). In addition, a simple relationship describing the relative strength of endogenous and exogenous impacts of landscape features on LST was found (Eendo > Eexo if ns > kgs2/5, where k is a city-specific parameter; otherwise, Eendo < Eexo). Overall, vegetation alleviates 40%-60% of the warming effect of built-up while surface wetness intensifies or reduces it depending on climate conditions. This study reveals a set of unifying quantitative relationships that effectively describes landscape impacts on LST across cities, grain and neighbor sizes, which can be instrumental towards the design of sustainable cities to deal with increasing temperature.

20.
Ying Yong Sheng Tai Xue Bao ; 31(4): 1063-1072, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32530179

RESUMO

We investigated the fire resistance conferred by different forest age groups (young, middle-age and mature forest) and organs (leaf, branch, and bark) of six typical tree species (Myrica rubra, Schima superba, Symplocos sumuntia, Machilus pingii, Castanopsis eyrei, and Quercus glauca) in Qingshigang national forest farm, Yanling County, Hunan Province, subtropical China. We measured morphological, physical, and chemical properties that could be used as proxies for fire resistance and examined the variances of fire resistance among different organs and age groups in the same tree species. Further, we comprehensively ranked all the tree species by their capacity in fire resistance. We found considerable variation in fire resistance among organs and age groups. Compared with branches and barks, leaves had relatively higher water content (53.7%), higher crude ash content (4.5%), and lower crude fiber content (23.9%). Fire resistance of trees decreased first and then increased with increasing stand age. Trees in middle-aged stage showed the lowest contents of water, crude ash, and crude fiber. The comprehensive scores of fire resistance for diffe-rent organs were significantly different among species. Fire resistance of leaves generally decreased in the order of M. pingii > C. eyrei > S. sumuntia > M. rubra > S. superba > Q. glauca. For branches, M. pingii and C. eyrei showed the strongest fire resistance, followed by M. rubra and S. superba. For barks, S. superba and C. eyrei were relatively stronger in fire resistance than other species, while M. pingii and Q. glauca were the weakest. The comprehensive scores of fire resistance performance of species were different. S. superba (1.033) and M. rubra (0.526) were the most fire-resistant species, while M. pingii (-0.405) and Q. glauca (-1.151) were the least fire-resistant. Therefore, S. superba and M. rubra were the preferred tree species for fire prevention forest belt in forests of subtropical southern China.


Assuntos
Incêndios , Theaceae , China , Florestas , Árvores
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