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1.
Ecology ; 105(5): e4284, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38494344

RESUMO

Resource partitioning is considered a key factor in alleviating competitive interactions, enabling coexistence among consumer species. However, most studies have focused on resource partitioning between species, ignoring the potentially critical role of intraspecific variation in resource use. We investigated floral resource partitioning across species, colonies, and individuals in a species-rich bumblebee community in the diversification center of bumblebees. We used a total of 10,598 bumblebees belonging to 13 species across 5 years in the Hengduan Mountains of southwest China. First, we evaluated the influence of a comprehensive set of floral traits, including both those related to attractiveness (flower color and shape) and rewards (pollen, sugar ratio, nectar volume, sugar concentration, and amino acid content) on resource partitioning at the species level in bumblebee-plant networks. Then, we explored intraspecific resource partitioning on the colony and individual levels. Our results suggest that bumblebee species differ substantially in their use of the available floral resources, and that this mainly depends on flower attractiveness (floral color and shape). Interestingly, we also detected floral resource partitioning at the colony level within all commonest bumblebee species evaluated. In general, floral resource partitioning between bumblebee individuals decreased with species- and individual-level variation in body size (intertegular span). These results suggest that bumblebee species may coexist via the flexibility in their preferences for specific floral traits, which filters up to support the co-occurrence of high numbers of species and individuals in this global hotspot of species richness.


Assuntos
Flores , Especificidade da Espécie , Animais , Abelhas/fisiologia , Flores/fisiologia , China , Ecossistema
2.
Pak J Pharm Sci ; 34(1): 35-39, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34248000

RESUMO

Multiple studies have discussed the associations between drugs affecting the renin-angiotensin-aldosterone system and the cancer risk, but their consequence s were conflicting. A meta-analysis of nested case-control studies published regarding this subject was conducted in our study, aims to estimate the association between ACEI/ARB and the cancer risk. Pubmed database was searched up to February, 1 2016 to identify eligible nested case-control studies, and we used Newcastle-Ottawa Scale (NOS) to assess quality of the studies. Pooled odds ratio (OR) and 95% confidence intervals (CIs) were calculated (with fixed effect model: Mantel-Haenszel). Publication bias and heterogeneity were evaluated before the calculation. Subgroup analysis and sensitivity analysis were also performed. Seven studies contributed to the analysis. Overall, ACEI/ARB use was not associated with the risk of cancer (OR=0.99, 95% CI 0.97-1.01), nor in long-term use patients (OR=0.97, 95% CI 0.92-1.01). ACEI may decrease cancer risk (OR=0.90, 95% CI 0.82-0.99). We observed no significant publication bias. In conclusion, ACEI/ARB use was not associated with cancer risk, nor in long-term use patients, but ACEI use may decrease cancer risk. More researches are needed to confirm these findings.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Neoplasias/induzido quimicamente , Neoplasias/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos , Antagonistas de Receptores de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Estudos de Casos e Controles , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Humanos , Neoplasias/epidemiologia , Preparações Farmacêuticas , Sistema Renina-Angiotensina/fisiologia , Fatores de Risco
3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1015996

RESUMO

Since the first discovery of lamprey variable lymphocyte receptors (VLRs) in 2004, the research and modification of VLRs have been very hot.VLRs have simple molecular structure, stable physical and chemical properties.VLRs can recognize a variety of antigens and have high affinity and strong specificity for proteins and polysaccharides, et al.In recent years, the recombinant molecules constructed by VLRs have been widely used in basic and application research in various fields.This paper reviews the latest application research of VLRs downstream in recent years.In tumor, VLRs can specifically and accurately identify carbohydrates and polysaccharides with only one functional group.It can be used as a sensitive anti-polysaccharide reagent to identify unique carbohydrate complexes on tumor cells and provide a new strategy for tumor targeted therapy.VLRs can also be combined with other classical therapies, such as modifying chimeric antigen receptors to express a synthetic receptor that redirects the targeted killing of T cells to the selected target.After recombination and modification, VLRs can also improve separation and purification of reagents.Research also indicates that VLRs play a role in aquatic diseases.These newly developed VLRs may be used as new reagents for identification, diagnosis and treatment.This paper describes the mechanism of VLRs diversity, and the relationship between VLRs with sugar biology and biomedical research, including the role of VLRs in improving separation and purification reagents, and the application of VLRs in the study of aquatic diseases.This review may provide reference for the application of VLR in disease drug research and development.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1015952

RESUMO

Paired box transcription factors (paired box, PAX) and their homologues found in a large number of vertebrates and invertebrates play a key role in many stages of embryonic development. The gene family gets its name because of its conserved paired domain, in addition to its octapeptide and homologous domain. According to the composition of the domain and sequence homology, the gene family is mainly divided into four subfamilies: PAX1 / 9 (PAX1, PAX9), PAX2 / 5 / 8 (PAX2, PAX5, PAX8), PAX3 / 7 (PAX3, PAX7), PAX4 / 6 (PAX4, PAX6). Each subfamily has different characteristic structures, such as PD-OP of PAX1 / 9 subfamily, PD-OP-PTHD of PAX2 / 5 / 8 subfamily, PD-OP-PTHD of PAX3 / 7 subfamily and PD and PTHD of PAX4 / 6 subfamily. Among them, the three members of the PAX family, PAX2 PAX4 and PAX6, play an important role in multiple stages of pancreatic development and differentiation, and also play a key role in regulating the synthesis and secretion of islet hormone. Understanding the original and differentiated roles of these transcription factors in pancreas will help finding potential treatment for diabetes. Furthermore, PAX1 / 9 families may serve as potential biomarkers for evaluation of tumor development and progression, such as the methylation levels of PAX1 and expression of PAX9 in tumor. PAX3 / 7 was transcription factors involved in the development of skeletal muscle. This paper reviewed the special and temporal expression of PAX genes in a wide variety of tumor and the function and structural abnormalities PAX gene were summarized in this paper.

5.
J Child Neurol ; 32(13): 1027-1034, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29046137

RESUMO

Because digital subtraction angiography (DSA) is not an ideal angiographic examination for moyamoya disease in the pediatric population, magnetic resonance angiography (MRA) provides a noninvasive contrast-free angiographic examination; whereas magnetic resonance imaging (MRI) provides superior spatial resolution and soft-tissue contrast for lesion assessment. Ninety patients with moyamoya disease were examined by MRI and DSA to assess the distribution of lesions and their diagnostic agreement between modalities. MRI examination revealed 439 lesions. Punctate lesions were the most abundant, followed by patchy lesions. These lesions generally covered a smaller area than the abnormal-vascular corresponding brain parenchyma. Steno-occlusive changes at bilateral anterior, medial, and posterior cerebral arteries were identified by MRA and DSA. MRI showed moderate agreement in identifying lesions after steno-occlusive changes in anterior and medial cerebral arteries, and good agreement in posterior cerebral arteries; 6% to 11% of cases were misdiagnosed by MRA.


Assuntos
Angiografia Digital , Encéfalo/diagnóstico por imagem , Angiografia Cerebral , Imageamento por Ressonância Magnética , Doença de Moyamoya/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Doença de Moyamoya/complicações , Estudos Retrospectivos
6.
Oncol Res ; 23(4): 147-54, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27053343

RESUMO

Bone morphogenetic protein-7 (BMP-7) inhibited the pathogenesis of renal injury in response to a variety of stimuli. However, little is known about the molecular regulation and mechanism of endogenous BMP-7 and its renoprotective functions. This study examined the regulation of BMP-7 and its role in the fibronectin secretion and apoptosis of NRK-52E cells resulting from transforming growth factor-ß1 (TGF-ß1) in vitro. Results showed that TGF-ß1 promoted factor-associated suicide (FAS), FAS ligand (FASL), fibronectin (FN), and miRNA-21 expression, while it downregulated phospho-Smad1 (pSmad1), pSmad5, and pSmad8 expressions in NRK-52E cells. In contrast, BMP-7 alleviated TGF-ß1-induced cell apoptosis, inhibited TGF-ß1-induced higher expression of miRNA-21 and FN, and enhanced TGF-ß1-attenuated phosphorylation of Smad1, Smad5, and Smad8. Furthermore, a chemical inhibitor of miRNA-21 also negatively affected TGF-ß1-induced apoptosis and FN secretion. On the other hand, overexpression of miRNA-21 counteracted the inhibitory effect of BMP-7 on TGF-ß1-induced FN secretion and apoptosis. However, BMP-7 showed no effects on TGF-ß1-induced FN secretion and apoptosis following knockdown of miRNA-21. Taken together, these findings demonstrated that BMP-7 might inhibit TGF-ß1-induced FN secretion and apoptosis by the suppression of miRNA-21 in NRK-52E cells.


Assuntos
Apoptose , Proteína Morfogenética Óssea 7/fisiologia , Fibronectinas/metabolismo , MicroRNAs/genética , Fator de Crescimento Transformador beta1/fisiologia , Animais , Proteína Morfogenética Óssea 7/farmacologia , Linhagem Celular , MicroRNAs/metabolismo , Ratos
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-279593

RESUMO

<p><b>OBJECTIVE</b>The aim of this study was to evaluate quantitatively the effectiveness and feasibility of the modified supracrestal fiberotomy (MSF) and the contact point reproximation (CPR) in decreasing the relapse of anterior segments rotating and/or crowding after orthodontic treatment.</p><p><b>METHODS</b>A total of 129 patients with crowding and/or rotated anterior teeth were selected for this study, and the average age was 13.07 years (54 males, 75 females). The modified supracrestal fiberotomy was performed on the anterior segments of patients in the experimental group (48 cases). After the anterior teeth were aligned, 23 of the 48 cases received a further treatment of the contact point reproximation on the anterior segments (the subgroup of MSF + CPR), and the other 25 subjects did not receive this treatment (the subgroup of MSF). The control group consisted of 81 cases. All cases wore Hawley retainers for 1.8 to 2.3 years, and all the patients were revisited 2.4 years postretention. The maxillary and mandibular dental models of all the patients were taken before treatment (T1), at the end of the treatment (T2) and 2.4 years postretention (T3).</p><p><b>RESULTS</b>The relapse rate in the experimental group [(T3-T2)/T1 x 100%] was 21.6%, lower than that in the control group (P < 0.001). The relapse rate of mandible in the subgroup of MSF + CPR was 6.56% lower than that of the subgroup of MSF (P < 0.05). But the relapse rate of maxillary in the subgroups of MSF + CPR was similar as that of the subgroup of MSF (P > 0.05).</p><p><b>CONCLUSION</b>The modified supracrestal fiberotomy can effectively alleviate relapse after orthodontic treatment of the crowding and/or rotation of anterior teeth. The treatment combining MSF and CPR can help maintain the stability of post-retention of mandibular anterior teeth.</p>


Assuntos
Adolescente , Pré-Escolar , Feminino , Humanos , Masculino , Má Oclusão , Terapêutica , Ortodontia Corretiva , Métodos , Fatores de Risco , Rotação , Prevenção Secundária , Fatores Sexuais , Estatísticas não Paramétricas , Extração Dentária , Técnicas de Movimentação Dentária , Resultado do Tratamento
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