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1.
Int J Mol Sci ; 22(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34639214

RESUMO

Lymphoid enhancer-binding factor 1 (LEF1) is a key transcription factor mediating the Wnt signaling pathway. LEF1 is a regulator that is closely associated with tumor malignancy and is usually upregulated in cancers, including colonic adenocarcinoma. The underlying molecular mechanisms of LEF1 regulation for colonic adenocarcinoma progression remain unknown. To explore it, the LEF1 expression in caco2 cells was inhibited using an shRNA approach. The results showed that downregulation of LEF1 inhibited the malignancy and motility associated microstructures, such as polymerization of F-actin, ß-tubulin, and Lamin B1 in caco2 cells. LEF1 inhibition suppressed the expression of epithelial/endothelial-mesenchymal transition (EMT) relevant genes. Overall, the current results demonstrated that LEF1 plays a pivotal role in maintaining the malignancy of colonic adenocarcinoma by remodeling motility correlated microstructures and suppressing the expression of EMT-relevant genes. Our study provided evidence of the roles LEF1 played in colonic adenocarcinoma progression, and suggest LEF1 as a potential target for colonic adenocarcinoma therapy.

2.
BMC Med Educ ; 21(1): 532, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34649532

RESUMO

BACKGROUND: Vertigo and dizziness (VD) are among the most frequently seen symptoms in clinics and are important for medical students, especially for those in Chinese standardized residency training (SRT). The aim of our study was to examine the PAL method's feasibility in the clinical teaching of VD-related diseases for SRT students in China. METHODS: This is a randomized, controlled, multicenter study. A total of 228 residents were invited to participate in this study, of which 198 completed the program. The students were randomized into two groups, and VD-related diseases were taught using lecture-based learning (control group) or peer-assisted learning (PAL). An examination paper and a rating scale were used to evaluate students' performance in the mastery of VD-related theoretical knowledge and clinical skills, meanwhile students' perceptions, satisfaction, and risk of burnout were also analyzed using a questionnaire. Independent-samples t-test and chi-square analysis were performed to evaluate statistical significance for continuous variables and categorical variables, respectively, using SPSS 18.0 software. RESULTS: The PAL group performed better in mastering theoretical knowledge and clinical skills than the control group. And more students believed that PAL could help improve their personal qualities such as teamwork skills. However, more students reported that PAL increased the risk of burnout. CONCLUSIONS: PAL was a suitable and effective method in the clinical teaching of some specialized diseases, especially it was recommended for students who had gained initial knowledge and skills, such as Chinese SRT students. However, we should draw attention to the increased risk of burnout if PAL is intended to be widely used in clinical teaching. TRIAL REGISTRATION: ISRCTN registry, ISRCTN53773239 , 05/07/2021, retrospectively registered.


Assuntos
Educação de Graduação em Medicina , Internato e Residência , Estudantes de Medicina , China , Tontura , Humanos , Grupo Associado , Ensino , Vertigem/diagnóstico
3.
Mol Pharm ; 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473523

RESUMO

Tirapazamine (TPZ) and its derivatives (TPZD) have shown their great potential for efficiently killing hypoxic cancer cells. However, unsatisfactory clinical outcomes resulting from the low bioavailability of the low-molecular TPZ and TPZD limited their further applications. Precise delivery and release of these prodrugs via functional nanocarriers can significantly improve the therapeutic effects due to the targeted drug delivery and enhanced permeability and retention (EPR) effect. Herein, zwitterionic block copolymer (BCP) micelles with aldehyde functional groups are prepared from the self-assembly of poly(2-methacryloyloxyethyl phosphorylcholine-b-poly(di(ethylene glycol) methyl ether methacrylate-co-4-formylphenyl methacrylate) [PMPC-b-P(DEGMA-co-FPMA)]. TPZD is then grafted onto PMPC-b-P(DEGMA-co-FPMA) to obtain a polymer-drug conjugate, PMPC-b-P(DEGMA-co-FPMA-g-TPZD) (BCP-TPZ), through the formation of a pH-responsive imine bond, exhibiting a pH-dependent drug release profile owing to the cleavage of the imine bond under acidic conditions. Outstandingly, BCP-TPZ shows around 13.7-fold higher cytotoxicity to hypoxic cancer cells in comparison to normoxic cancer cells evaluated through an in vitro cytotoxicity assay. The pH-responsiveness and hypoxia-specific cytotoxicity confer BCP-TPZ micelles a great potential to achieve precise delivery of TPZD and thus enhance the therapeutic effect toward tumor-hypoxia.

4.
Microb Pathog ; : 105168, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34478857

RESUMO

Pneumonia is one of the most frequent disorder induced by S. aureus infection and accounts for 13.3% of the all the infections caused by staphylococcus. In the present study effect of diphenyl pyrimidine was investigated against Staphylococcus aureus (S. aureus) induced pneumonia in the rat model. The results demonstrated that diphenyl pyrimidine treatment of the rats effectively prevented S. aureus induced increase in mortality in dose-dependent manner. Diphenyl pyrimidine treatment inhibited histopathological changes in S. aureus infected rat lungs. Treatment of the rats with 1.25, 2.5, 5 and 10 mg/kg doses of diphenyl pyrimidine significantly (P < 0.05) reversed S. aureus infection induced increase in interleukin (IL)-1ß, IL-18 and tumor necrosis factor (TNF)-α levels. Treatment with 1.25, 2.5, 5 and 10 mg/kg doses of diphenyl pyrimidine significantly (P < 0.05) reversed S. aureus infection induced increase nucleotide-binding domain and leucine-rich repeat containing (NLR) protein (NLRP3), apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC) and caspase-1 protein expression in rat lungs in dose-dependent manner. The NLRP3, ASC and caspase-1 mRNA level in S. aureus infected rat pulmonary tissues was significantly (P < 0.05) reduced by diphenyl pyrimidine treatment in dose-dependent manner. Thus, diphenyl pyrimidine protects S. aureus-induced pneumonia through suppression of NLRP3 and inflammatory cytokine expression. Therefore, diphenyl pyrimidine can be of therapeutic importance for the treatment of S. aureus induced pneumonia.

5.
J Endod ; 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34520812

RESUMO

INTRODUCTION: This study proposes a novel data pipeline based on micro-CT data for training the U-Net network to realize the automatic and accurate segmentation of pulp cavity and tooth on cone-beam computed tomography (CBCT) images. METHODS: We collected CBCT data and micro-CT data of thirty teeth. CBCT data were processed and transformed into a small field of view and high-resolution CBCT images of each tooth. Twenty-five sets were randomly assigned to the training set and the remaining five sets to the test set. We used two data pipelines for U-Net network training: one manually labeled by an endodontic specialist as the control group, and one processed from the micro-CT data as the experimental group. The 3D models constructed using micro-CT data in the test set were taken as the ground truth. Dice similarity coefficient (DSC), precision rate (PR), recall rate (RR), average symmetric surface distance (ASSD), Hausdorff distance (HD) and morphological analysis were utilized for performance evaluation. RESULTS: The segmentation accuracy of the experimental group measured by DSC, PR, RR, ASSD, and HD were 96.20±0.58%, 97.31±0.38%, 95.11±0.97%, 0.09±0.01mm, and 1.54±0.51mm in tooth and 86.75±2.42%, 84.45±7.77%, 89.94±4.56%, 0.08±0.02mm, 1.99±0.67mm in the pulp cavity, respectively, which were better than the control group. Morphological analysis suggested the segmentation results of the experimental group were better than those of the control group. CONCLUSIONS: This study proposed an automatic and accurate approach for tooth and pulp cavity segmentation on CBCT images, which can be applied in researches and clinical tasks.

6.
Biofouling ; : 1-12, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34579611

RESUMO

The antifungal resistence of oral candidiasis is a serious clinical issue. The in vivo efficacy of farnesol combined with antifungals for oral candidiasis remain unknow. The possible therapeuticeffects of a combination of farnesol and antifungal drugs and the regulation of inflammatorycytokines in murine oral candidiasis were investigated in this study. An experimental oral candidiasis model was constructed using ICR mice. Farnesol at 25 and 50 lM did not change IL-17,IFN-γ and TNF-α production during oral candidiasis compared with that of the control infected mice. The co-applications of farnesol (50 lM) and nystatin, farnesol (4 lM, 8 lM) and itraconazole, farnesol (25, 50 lM), and fluconazole enhanced the therapeutic activity of the antifungalagents alone against oral candidiasis. The effective combinations reduced the number of colonyforming units (CFU) of Candida albicans isolated from the oral cavity and oral lesions onthe tongue.

7.
J Plant Physiol ; 266: 153510, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34521019

RESUMO

Source sink balance is one of the major determinants of carbon partitioning in plants. However, its effects on photosynthesis in fruit trees are largely unknown. In this work, the effects of low sink demand on net photosynthetic rate (Pn) and chlorophyll fluorescence after fruit removal (-fruit) in peach (Prunus persica (L.) Batsch cv. 'Zaojiubao') trees were investigated. The stepwise energy flow through photosystem II (PSII) at the reaction center (RC) was analyzed with quantitative analyses of fluorescence transient, also called JIP-test. We found that Pn was significantly lower and closely correlated to the leaf stomatal conductance (Gs) of -fruit trees than that of fruit retained (+fruit) trees. Leaf temperature (Tleaf) of -fruit trees was remarkably higher than that of +fruit trees. Day-time-period assays of chlorophyll (Chl) fluorescence revealed that, in the leaves of -fruit trees, the fluorescence parameters, such as NPQ (non-photochemical quenching coefficient) and ΦD0 (maximum quantum yield of non-photochemical de-excitation), decreased in the morning and recovered to the normal level in the afternoon, whereas other parameters, such as ΦE0 (quantum yield for electron transport at t = 0), Ψ0 (probability that a trapped exciton moves an electron to QA pool), F0 (minimum fluorescence, when all PSII RCs are open) and Wk (relative variable fluorescence at 300 µs of the chlorophyll fluorescence transient), did not. These results suggest that OEC complex and QA pool were irreversibly affected by low sink demand, whereas light harvest antenna and PSII potential efficiency retained a strong ability to recover.

8.
Mikrochim Acta ; 188(9): 289, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34355248

RESUMO

A photoelectrochemical (PEC) aptasensor was designed and constructed by Bi24O31Cl10/BiOCl heterojunction as a photoelectric active material for realizing the determination of trace ciprofloxacin (CIP) in water. Compared with Bi24O31Cl10, Bi24O31Cl10/BiOCl heterojunction possessed the improvement of light harvesting and the enhancement of photocurrent signal. The formation of heterojunction between Bi24O31Cl10 and BiOCl can accelerate the transportation efficiency and inhibit the recombination rate of photoinduced carriers. Based on the excellent PEC performance, CIP aptamer was introduced on the modified Bi24O31Cl10/BiOCl/indium tin oxide (ITO) electrode for fabricating a PEC aptasensor. Owing to the combination between aptamer and CIP, CIP-aptamer complex can block the transfer of charge, leading to the reduction of photocurrent response. The PEC aptasensor possessed high sensitivity with a wide detection range (5.0~1.0 × 104 ng L-1) and a low detection limit (1.67 ng L-1, S/N = 3). The PEC aptasensor with good selectivity and reproducibility has been applied to the determination of CIP in water.

9.
Acta Biomater ; 131: 544-554, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265475

RESUMO

Diabetic wound healing is highly desirable but remains a great challenge owing to the continuous damage of excess reactive oxygen species (ROS) and degradation of therapeutic peptide drugs by over-expressed matrix metalloproteinase (MMP). Herein, we developed a stimuli-responsive smart dressing for theranostics of diabetic wounds using graphene quantum dots-decorated luminescent porous silicon (GQDs@PSi), which was further loaded with peptide and embedded in chitosan (CS) film. The confinement of GQDs in nanochannels of PSi endowed GQDs@PSi with efficient fluorescence resonance energy transfer (FRET) effect, leading to initial red fluorescence of PSi with complete quench of GQD's blue fluorescence. Furthermore, the decoration of GQDs on PSi surface significantly enhanced the loading capacity for peptide drugs including epidermal growth factor (EGF) and insulin (Ins) which can promote diabetic wounds healing. The peptides coloaded in GQDs@PSi exhibited sustained release behavior and could be protected in presence of MMP owing to size exclusion of PSi's nanochannels. As H2O2-triggered oxidation of PSi lead to weakened FRET effect and degradation of PSi, GQDs@PSi demonstrated H2O2-responsive ratiometric fluorescence change (from red PSi to blue GQDs) and drug release behavior. In combination with CS's degradation in the acidic and oxidation microenvironment, the smart dressing also showed stimuli-responsive drug release toward slightly acid and highly oxidative conditions in diabetic wounds. In vitro and in vivo results demonstrated the smart dressing enhanced the proliferation and migration of cells as well as significantly healed diabetic wounds. Real-time indicating of the exacerbation or healing of diabetic wounds was also realized using the rate of fluorescent discoloration of the dressing. STATEMENT OF SIGNIFICANCE: In this work, a dual luminescent nanomaterial was created by hosting graphene quantum dots (GQDs) in the nanochannel of porous silicon (PSi), which was further applied for theranostics of diabetic wound. The synergistic effect of the host-guest nanohybrid is significant. The GQDs can significantly improve the capacity for peptide drug loading and form a stimuli-response visual ratiometric sensor with luminescent PSi, which can also protect and sustain release of peptide drugs for effective diabetic wounds treatment. After embedded in a chitosan film, the smart dressing displayed H2O2-responsive visual ratiometric fluorescence change and drug release behavior. In vitro and in vivo results demonstrated the smart dressing enhanced the proliferation and migration of cells as well as significantly healed diabetic wounds.


Assuntos
Diabetes Mellitus , Grafite , Pontos Quânticos , Bandagens , Humanos , Peróxido de Hidrogênio , Porosidade , Medicina de Precisão , Silício
10.
Mol Cancer Ther ; 20(9): 1735-1742, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34224363

RESUMO

The objective of this study was to evaluate the real-world application, efficacy, and safety data of olaparib for maintenance therapy and active treatment in patients with ovarian cancer in China. Patients with ovarian cancer from 17 institutions in China treated with olaparib as maintenance or active therapy from January 2018 to March 2020 were included in this study. The medical records were reviewed, and follow-up information was collected for analysis of the patients' clinicopathologic characteristics as well as the effectiveness and safety of olaparib. A total of 251 patients receiving olaparib were included, with 84 as maintenance therapy after first-line chemotherapy (FL-M), 97 as maintenance therapy after platinum-sensitive recurrence (PSR-M), and 70 as active treatment (AT). The probability of progression-free survival (PFS) at 12 months was 87.6% in the FL-M group and 63.8% in the PSR-M group. According to the multivariate analysis, complete response (CR) to chemotherapy for the PSR-M patients was the only factor affecting the PFS (HR = 0.414, P = 0.014), and platinum sensitivity was the only factor affecting PFS improvement in the AT group (HR = 0.317, P = 0.009). In the AT group, the objective response rate was 37.1%, the CR rate was 7.1%, and 30% of the patients had stable disease. Eight (3.2%) patients discontinued olaparib due to toxicity. Anemia was the most common adverse event. In conclusion, olaparib is effective and well tolerated in the real-world setting of ovarian cancer treatment. Platinum sensitivity is positively correlated to the effectiveness of olaparib in both maintenance and active treatment.

11.
J Exp Clin Cancer Res ; 40(1): 220, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210327

RESUMO

BACKGROUND: Metastasis is a major challenge in cervical cancer treatment. Previous studies have shown that the dual functional protein apurinic/apyrimidinic endonuclease 1 (APE1) promotes tumor metastasis and is overexpressed in cervical cancer. However, the biological role and mechanism of APE1 in cervical cancer metastasis have rarely been studied. METHODS: We used gene set enrichment analysis (GSEA) to determine the APE1-related signaling pathways in cervical cancer. To investigate the role and mechanism of APE1 in cervical cancer metastasis and invasion, immunohistochemistry, immunofluorescence, western blotting, secondary structure prediction, coimmunoprecipitation, luciferase reporter, and electrophoretic mobility shift assays were performed. The inhibitory effects of the APE1 redox function inhibitor APX3330 on cervical cancer metastasis were evaluated using animal models. RESULTS: Clinical data showed that high expression of APE1 was associated with lymph node metastasis in cervical cancer patients. GSEA results showed that APE1 was associated with epithelial to mesenchymal transition (EMT) in cervical cancer. Ectopic expression of APE1 promoted EMT and invasion of cervical cancer cells, whereas inhibition of APE1 suppressed EMT and invasion of cervical cancer cells in a redox function-dependent manner. Notably, APE1 redox function inhibitor APX3330 treatment dramatically suppressed cervical cancer cell lymph node and distant metastasis in vivo. Furthermore, we found that APE1 enhanced the interaction between ZEB1 and the E-cadherin promoter by binding to ZEB1, thereby suppressing the expression of E-cadherin, a negative regulator of EMT. CONCLUSION: Our findings help to elucidate the role played by APE1 in cervical cancer metastasis and targeting APE1 redox function may be a novel strategy for inhibiting cervical cancer metastasis.

12.
Biomed Res Int ; 2021: 6661698, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34258277

RESUMO

Objective: Little observational data exist regarding the use of cisplatin, etoposide, and bleomycin (BEP) chemotherapy regimen in patients with gestational trophoblastic neoplasia (GTN). Methods: This is a retrospective study of 95 patients with GTN in our center from June/2010 to June/2018. All patients received at least 2 cycles of BEP chemotherapy. The primary outcomes were the rate of complete remission (CR) and overall survival (OS). The secondary outcomes were disease-free survival (DFS), pregnancy rates after BEP exposure, drug resistance rate, and other adverse events. Results: Of the 95 patients included, 66 (69.5%) patients received BEP as primary treatment and 29 (30.5%) were Salvage chemotherapy. The median age at diagnosis was 37 years (range 29.75-46) and 34 years (range 27-40) in two groups, respectively. The median WHO prognostic scores were 6 (range 3.5-8), and 77.32% of patients were FIGO stage III-IV in the primary treatment group. The median WHO prognostic scores were 5 (range 3-9), and 66.55% of patients were FIGO stage III-IV in the salvage treatment group. Median cycles of BEP treatment were 4 (3, 5) and 3 (2, 4) in two groups, respectively. In the primary chemotherapy group, 18.2% received additional hysterectomy, 4.5% received UAE for vaginal bleeding, and 1.52% received whole-brain radiotherapy. In the salvage chemotherapy group, 20.7% received hysterectomy, 6.9% received lobectomy, 3.4% received hysteroscopic lesion resection, and 3.4% received whole-brain radiotherapy. CR rates to initial chemotherapy were 86.4%, including 87.9% in the primary chemotherapy group and 82.8% in the salvage chemotherapy group. No predictive factor of chemotherapy resistance was identified. The rate of 5 year-DFS was 96.52% (95% CI 86.78-99.12) in the primary chemotherapy group and 92.44% (95% CI 73.02-98.06) in the salvage chemotherapy group. The rate of 5 year-OS was 98.31% (95% CI 88.57-99.76) and 95.65% (95% CI 79.93-99.38) in the two groups, respectively. During the treatment, neutropenia, thrombocytopenia, anemia, and liver dysfunction occurred in 80.3%, 6.1%, 25.8%, and 50% primary chemotherapy patients and 82.8%, 31%, 10.3%, and 86.2% salvage chemotherapy patients. In patients with fertility requirements, live birth rates were 100% (10/10) in primary chemotherapy patients and 80% (4/5) in salvage chemotherapy patients. Conclusions: BEP regimen was effective in the treatment of GTINs. The treatment was well tolerated, with no safety concerns on patients' fertility.

13.
Biofabrication ; 13(4)2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34315135

RESUMO

Three-dimensional (3D) bioprinting has been widely applied in the field of biomedical engineering because of its rapidly individualized fabrication and precisely geometric designability. The emerging demand for bioprinted tissues/organs with bio-inspired anisotropic property is stimulating new bioprinting strategies. Stereotactic bioprinting is regarded as a preferable strategy for this purpose, which can perform bioprinting at the target position from any desired orientation in 3D space. In this work, based on the motion characteristics analysis of the stacked bioprinting technologies, mechanism configurations and path planning methods for robotic stereotactic bioprinting were investigated and a prototype system based on the double parallelogram mechanism was introduced in detail. Moreover, the influence of the time dimension on stereotactic bioprinting was discussed. Finally, technical challenges and future trends of stereotactic bioprinting within the field of biomedical engineering were summarized.

14.
Arch Biochem Biophys ; 708: 108963, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34126088

RESUMO

Extracellular vesicles (EVs) are important intercellular communication messengers. Half of the published studies in the field are in vitro cell culture based in which bovine serum in various concentrations and forms is used to facilitate the production of extracellular vesicles. 'Exosome depleted serum' is the type of bovine serum most widely used in the production of human EVs. Herein, we demonstrate that, despite the initial caution raised in 2014 about the persistence of bovine EVs, 'exosome depleted serum' was still used in 46% of publications on human or rodent EVs between 2015 and 2019. Using nanoparticle tracking analysis combined with detergent lysis of vesicles as well as bovine CD9 ELISA, we show that there were approximately 5.33 x 107/mL of bovine EVs remaining in the 'exosome depleted serum'. Importantly, the 'exosome depleted serum' was relatively enriched in small EVs by approximately 2.7-fold relative to the large EVs compared to that in the original serum. Specifically, the percentage of small EVs in total vesicles had increased from the original 48% in the serum before ultracentrifugation to 92% in the 'exosome depleted serum'. Furthermore, the pervasive bovine EVs carried over by the 'exosome depleted serum', even when the lowest concentration (0.5%) was used in cell culture, resulted in a significant contamination of human EVs in cell culture conditioned medium. Our findings indicate that the use 'exosome depleted serum' in cell culture-based studies may introduce artefacts into research examining the function of human and rodent EVs, in particular those involving EV miRNA. Thus, we appeal to the researchers in the EV field to seriously reconsider the practice of using 'exosome depleted serum' in the production of human and other mammalian EVs in vitro.


Assuntos
Técnicas de Cultura de Células/métodos , Meios de Cultivo Condicionados , Exossomos/metabolismo , Soro/citologia , Animais , Bovinos , Humanos
15.
Artigo em Inglês | MEDLINE | ID: mdl-34073465

RESUMO

Heterogeneities of individual attributes and behaviors play an important role in the complex process of epidemic spreading. Compared to differential equation-based system dynamical models of infectious disease transmission, individual-based epidemic models exhibit the advantage of providing a more detailed description of realities to capture heterogeneities across a population. However, the higher granularity and resolution of individual-based epidemic models comes with the cost of increased computational complexities, which result in difficulty in formulating individual-based epidemic models with mathematics. Furthermore, it requires great effort to understand and reproduce existing individual-based epidemic models presented by previous researchers. We proposed a mathematical formulation of heterogeneous individual-based epidemic models using matrices. Matrices and vectors were applied to represent individual attributes and behaviors. We derived analytical results from the matrix-based formulations of individual epidemic models, and then designed algorithms to force the computation of matrix-based individual epidemic models. Finally, we used a SARS epidemic control as a case study to verify the matrix-based formulation of heterogeneous individual-based epidemic models.


Assuntos
Doenças Transmissíveis , Epidemias , Síndrome Respiratória Aguda Grave , Algoritmos , Doenças Transmissíveis/epidemiologia , Humanos , Matemática , Síndrome Respiratória Aguda Grave/epidemiologia
16.
J Environ Manage ; 295: 113077, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34146778

RESUMO

Eco-tourism is rapidly developing in giant panda nature reserves in China, and is considered a popular tool for biodiversity conservation and the welfare of local communities. However, there is lack of empirical evidence on whether eco-tourism promotes the conservation behavior of local communities members, who live around nature reserves. To this end, this study constructed a framework to measure households' forest conservation activities, and conducted a questionnaire survey in 12 giant panda nature reserves in Sichuan Province, China. A total of 686 valid samples were obtained. A logit model was used to confirm whether income from community-based ecotourism (CBET) could enhance households' conservation behavior. The results show that households prefer three types of conservation practices, and CBET could significantly improve the income of households engaged in it. Income from CBET has motivated local households to participate in conservation activities; however, but the effects are different. In all three conservation activities, income from CBET has shown significant effects on promoting forest maintenance and protection activities, but not on reforestation ones. The results of this research could help us better understand the relationship between CBET and local households' conservation behavior. It also provides information for policymakers seeking for the best way to balance conservation and development.


Assuntos
Ursidae , Animais , China , Conservação dos Recursos Naturais , Ecossistema , Turismo
17.
J Sleep Res ; : e13419, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131989

RESUMO

As the pace of life accelerates, poor sleep quality has become a common health problem. A wealth of sleep studies based on electroencephalogram (EEG) have found that poor sleep quality has decreased alpha rhythm during night-time sleep. However, whether the EEG rhythm during an afternoon nap has a similar impairment has seldom been investigated. By recruiting 35 subjects for a 90-min nap, we explored the relationship between sleep quality and the alpha rhythm, and the contribution of naps to subjective sleep experience. We found that the power of alpha rhythm in the occipital lobe negatively correlated with sleep quality. However, there was no correlation between the sleep quality at night and the sleep duration of the nap, nor the sleep quality and the proportion of each sleep period of a nap. Our present results indicated that the quality of night-time sleep did not affect the macrostructure of the nap. Interestingly, the negative correlation between the alpha rhythm of a nap and sleep quality at night continuously existed in Wake, N1 sleep, and N2 sleep, and had the most substantial value during N2 sleep of a nap. This implies that an impaired occipital lobe alpha rhythm is a robust biomarker for poor sleep. The research is of particular significance for developing electrical neural stimulation therapy to improve sleep quality, especially for the stimuli regions for selection and the time windows for implementation.

18.
Sci Rep ; 11(1): 10791, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031441

RESUMO

Two ATP-binding cassette transporters, ABCB1/MDR1 and ABCG2/BCRP, are considered the most critical determinants for chemoresistance in hepatocellular carcinoma. However, their roles in the chemoresistance in liver cancer stem cells remain elusive. Here we explored the role of inhibition of MDR1 or ABCG2 in sensitizing liver cancer stem cells to doxorubicin, the most frequently used chemotherapeutic agent in treating liver cancer. We show that the inhibition of MDR1 or ABCG2 in Huh7 and PLC/PRF/5 cells using either pharmacological inhibitors or RNAi resulted in the elevated level of intracellular concentration of doxorubicin and the accompanied increased apoptosis as determined by confocal microscopy, high-performance liquid chromatography, flow cytometry, and annexin V assay. Notably, the inhibition of MDR1 or ABCG2 led to the reversal of the chemoresistance, as evident from the enhanced death of the chemoresistant liver cancer stem cells in tumorsphere-forming assays. Thus, the elevation of effective intracellular concentration of doxorubicin via the inhibition of MDR1 or ABCG2 represents a promising future strategy that transforms doxorubicin from a traditional chemotherapy agent into a robust killer of liver cancer stem cells for patients undergoing transarterial chemoembolization.

20.
Aging (Albany NY) ; 13(7): 10141-10157, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33819181

RESUMO

This study aimed to elucidate whether dietary amino acids (AAs) composition is associated with type 2 diabetes mellitus (T2DM) and to investigate how serum AAs profiles mediated this association. Two prospective cohorts of 1750 and 4024 adults were enrolled. Dietary AAs compositions index (AACI) was developed to reflect the overall quality of dietary AAs composition. Multivariate linear regression and logistic regression models were used to examine associations of AACI and T2DM. The AACI was associated with the incidence of T2DM with the relative risk and 95%CI from the bottom to the top tertiles being 1.00, 1.49 (0.88-2.51) and 2.27 (1.20-4.28), and 1.00, 1.58 (1.13-2.19) and 2.33 (1.56-3.47) in the two cohorts, respectively. The AACI was positively associated with serum valine, isoleucine, glutamic acid and phenylalanine, and it was negatively associated with serum glycine and histidine in both cohorts (P<0.01). Valine, glutamic acid and histidine consistently and partially mediated the association between the AACI and T2DM in the two cohorts, with total mediation effects of 33.4% and 54.6%, respectively. Dietary AAs composition was associated with the incidence of T2DM, meanwhile, the relationship was mediated by some degree of serum AAs. Future dietary strategies should focus on the improvement of the overall quality of dietary AAs compositions.


Assuntos
Aminoácidos/sangue , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Adulto , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Dieta , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
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