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1.
Nano Lett ; 23(18): 8498-8504, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37695649

RESUMO

Reining in deformation twinning is crucial for the mechanical properties of hexagonal close-packed (HCP) metals and hinges on an explicit understanding of the twinning nucleation mechanism. Unfortunately, it is often suggested rather than conclusively demonstrated that twinning nucleation can be mediated by pure atomic shuffles. Herein, by utilizing in situ high-resolution transmission electron microscopy, we have dissected the atomic shuffling mechanism during the {101̅2} twinning nucleation in rhenium nanocrystals, which revealed the emergence of an intermediate body-centered tetragonal (BCT) structure. Specifically, the double-layered prismatic planes initially shuffle into single-layered {11̅0}BCT planes; subsequently, adjacent {22̅0}BCT planes shuffle in opposite directions to form the basal planes of the twin embryo. This shuffling mechanism is further corroborated by molecular dynamic simulations. The finding provides direct evidence of shuffle-dominated twinning nucleation with atomic details that may lead to better control of this critical twinning mode in HCP metals.

2.
Glob Chang Biol ; 29(4): 1054-1061, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36408718

RESUMO

Atmospheric nitrogen (N) deposition is composed of both inorganic nitrogen (IN) and organic nitrogen (ON), and these sources of N may exhibit different impacts on ecosystems. However, our understanding of the impacts of N deposition is largely based on experimental gradients of INs or more rarely ONs. Thus, the effects of N deposition on ecosystem productivity and biodiversity may be biased. We explored the differential impacts of N addition with different IN:ON ratios (0:10, 3:7, 5:5, 7:3, and 10:0) on aboveground net primary productivity (ANPP) of plant community and plant diversity in a typical temperate grassland with a long-term N addition experiment. Soil pH, litter biomass, soil IN concentration, and light penetration were measured to examine the potential mechanisms underlying species loss with N addition. Our results showed that N addition significantly increased plant community ANPP by 68.33%-105.50% and reduced species richness by 16.20%-37.99%. The IN:ON ratios showed no significant effects on plant community ANPP. However, IN-induced species richness loss was about 2.34 times of ON-induced richness loss. Soil pH was positively related to species richness, and they exhibited very similar response patterns to IN:ON ratios. It implies that soil acidification accounts for the different magnitudes of species loss with IN and ON additions. Overall, our study suggests that it might be reasonable to evaluate the effects of N deposition on plant community ANPP with either IN or ON addition. However, the evaluation of N deposition on biodiversity might be overestimated if only IN is added or underestimated if only ON is added.


Assuntos
Ecossistema , Pradaria , Nitrogênio , Biodiversidade , Biomassa , Plantas , Solo
3.
New Phytol ; 234(6): 2003-2017, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34449895

RESUMO

Climate extremes pose enormous threats to natural ecosystems. Arbuscular mycorrhizal (AM) fungi are key plant symbionts that can affect plant community dynamics and ecosystem stability. However, knowledge about how AM fungal communities respond to climate extremes in natural ecosystems remains elusive. Based on a grassland extreme drought experiment in Inner Mongolia, we investigated the response of AM fungal communities to extreme drought in association with plant communities. The experiment simulated two types of extreme drought (chronic/intense) of once-in-20-year occurrence. AM fungal richness and community composition exhibited high sensitivity to extreme drought and were more sensitive to intense drought than chronic drought. This community sensitivity (i.e. decline in richness and shifts in community composition) of AM fungi can be jointly explained by soil moisture, plant richness, and aboveground productivity. Notably, the robustness of the plant-AM fungal community co-response increased with drought intensity. Our results indicate that AM fungal communities are sensitive to climate extremes, and we propose that the plant community mediates AM fungal community responses. Given the ubiquitous nature of AM associations, their climate sensitivity may have profound consequences on plant communities and ecosystem stability under climate change.


Assuntos
Micorrizas , Secas , Ecossistema , Fungos , Pradaria , Micorrizas/fisiologia , Plantas/microbiologia , Solo , Microbiologia do Solo
4.
Plant Dis ; 2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36210333

RESUMO

Morel mushroom (Morchella spp.) is a valuable mushroom, which has extremely high nutritional and economic value. In the early March of 2022, a serious rot disease was observed on approximately 30% fruiting bodies at an M. esculenta farm of Suzhou City, Anhui province, China. A white mold-like hyphae was initially present on the pileus, which then gradually spread to the whole fruiting body, eventually resulting in softening of the fruiting body and death. This disease developed rapidly at relatively high temperature (>20°C) and humidity (>85%), resulting in approximately 80% loss of yield. Twenty infected tissues were cut into small pieces (5 × 5 mm) and placed on potato dextrose agar (PDA) and incubated at 25°C for 5 days. Fifteen morphologically similar isolates were obtained and purified using the single spore isolation technique. Colonies of these isolates were yellowish-white, and tomentose with thick aerial hyphae after 7 days at 25°C on PDA plates. Conidiophores were dimorphic: primary conidiophores were Verticillium-like, secondary conidiophores were penicillate. Primary conidiophore stipe length ranged from 68.6 to 180.5 µm, and the base width was 3.2-5.6 µm. Phialides were solitary, straight, generally slightly tapering towards the tip, each producing a small, hyaline drop of conidia. Secondary conidiophores stipe length ranged from 68.4 to 120.5 µm, the base measured 3.3-6.1µm. Phialides were straight to slightly curved, slightly flask-shaped, with widest point below the middle, slightly tapering in the upper part, without visible collarette. Conidia were colorless, smooth, slightly curved, and distally broadly rounded with an average size of 6.3 to 8.2 × 2.4 to 3.7 µm (n=30). These isolates were initially identified as Clonostachys rosea based on morphological features (Schroers et al. 1999). To confirm the identity of C. rosea, primers ITS1/ITS4 (White et al. 1990) and EF1-728F/ EF1-986R (Carbone and Kohn 1999), were used to amplify the internal transcribed spacer (ITS), and translation elongation factor 1-alpha (EF-1α) genes of the representative isolate 5-3-2. These sequences were deposited in GenBank (GenBank accession nos. ON614093 and ON630916) and had 100% and 99.45% nucleotide identity with Clonostachys rosea E5R(17) and Clonostachys rosea KGSJ26 (GenBank accession nos. MK752437 and MT462122), respectively. Single conidium were isolated and multiplied on PDA for pathogenicity testing. To fulfill Koch's postulates, pathogenicity tests were performed using the fruiting bodies. Spores of C. rosea isolates 5-3-2 were collected and diluted with sterile distilled water at a concentration of 1 × 106 conidia/ml. Five healthy fruiting bodies were inoculated with 1 ml of the spore suspension, which were maintained in an artificial climate chamber at 22°C and 85% humidity. Sterile water inoculated on other 10 healthy fruiting bodies served as control. Mycelia grew rapidly and overgrew more than half of the fruiting bodies within 3 days. The fruiting bodies died five days after inoculation. Clonostachys rosea isolates were re-isolated from symptomatic fruiting bodies and identified by the methods described above. The control group showed no symptoms. The experiment was conducted twice. To our knowledge, this is the first identification of Clonostachys rosea as the causal agent of the Morchella sextelata rot.

5.
Zhongguo Zhong Yao Za Zhi ; 46(7): 1839-1845, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33982489

RESUMO

According to the notice on revision of the instructions for traditional Chinese medicine injections(TCMIs) issued by the National Medical Products Administration(NMPA) from January 2006 to May 2020, the revised contents in the instructions for 29 varieties involved in the notice were sorted out, and the existing problems in the instructions for TCMIs were analyzed, so as to provide the basis for dynamic revision of the instructions. It was found that the revised items of instructions for 29 varieties all involved adverse reactions, contraindications and precautions, and warnings were added for 82.76% of 29 TCMIs preparations, indicating that all the revised contents were related to safety issues. In addition, 33.33% of the drugs risks mentioned in the precautions were not indicated in the adverse reactions; 82.76% instructions did not indicate drug interactions; 17.24% instructions lacked medication notes for special populations; 48.28% instructions did not indicate traditional Chinese medicine(TCM) syndromes of the main disease; 44.83% instructions did not indicate the type and stage of indication; and 86.21% instructions did not indicate the course of treatment. It could be concluded that the instructions for TCMIs have known risks of drugs that are not fully reflected in adverse reactions and the effective information is not comprehensive. The risk control measures proposed in the precautions need to have aftereffect evaluation and there is a lack of drug interactions and medications for special populations. As an important part of the full life-cycle management of drugs, the revision of instructions for TCMIs should be continuously improved to provide the basis for safe and reasonable application of TCMIs. Based on the above problems, it is proposed that the marketing license holder as the main body of the revision of instructions should actively carry out post-marketing basic and clinical research in accordance with the characteristics of TCM, combine the updated research with the guidance of TCM theory and improve the revision level of instructions for TCMIs to provide the basis for post-marketing evaluation.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Injeções , Síndrome
6.
Chem Soc Rev ; 48(11): 3015-3072, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31098599

RESUMO

Functional nanostructured materials have attracted great attention over the past several decades owing to their unique physical and chemical properties, while their applications have been proven to be advantageous not only in fundamental scientific areas, but also in many technological fields. Spray pyrolysis (SP), which is particularly facile, effective, highly scalable and suitable for on-line continuous production, offers significant potential for the rational design and synthesis of various functional nanostructured materials with tailorable composition and morphology. In this review, we summarize the recent progress in various functional nanostructured materials synthesized by SP and their potential applications in energy storage and conversion. After a brief introduction to the equipment, components, and working principles of the SP technique, we thoroughly describe the guidelines and strategies for designing particles with controlled morphology, composition, and interior architecture, including hollow structures, dense spheres, yolk-shell structures, core-shell structures, nanoplates, nanorods, nanowires, thin films, and various nanocomposites. Thereafter, we demonstrate their suitability for a wide range of energy storage and conversion applications, including electrode materials for rechargeable batteries, supercapacitors, highly active catalysts for hydrogen production, carbon dioxide reduction and fuel cells, and photoelectric materials for solar cells. Finally, the potential advantages and challenges of SP for the preparation of nanostructured materials are particularly emphasized and discussed, and several perspectives on future research and development directions of SP are highlighted. We expect that this continuous, one-pot, and controllable synthetic technology can serve as a reference for preparing various advanced functional materials for broader applications.

7.
Zhongguo Zhong Yao Za Zhi ; 45(3): 674-682, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237528

RESUMO

This article is aimed to reevaluate the systematic reviews(Meta-analysis) of traditional Chinese medicine in the treatment of ulcerative colitis, and provide reference for evidence-based decision-making of traditional Chinese medicine(TCM). According to the preferred reporting items for overviews(preferred reporting items for overview of systematic reviews, PRIO-harms), the main Chinese and English electronic literature databases(PubMed, Cochrane Library, EMbase, CNKI, CBM, etc.) were retrieved, supplemented by manual retrieval. Systematic reviews for the treatment of ulcerative colitis with Chinese medicine up to February 2019 were included. Two researchers independently performed literature screening and data extraction. The methodology quality, reporting quality and evidence quality of the literature were evaluated by AMSTAR 2 tool, PRISMA scale and GRADE system respectively. Subgroup analysis was performed by using RevMan 5.3 software. A total of 21 systematic reviews were included, and the interventions mainly included TCM internal and external treatment, with 53 outcome indicators. The AMSTAR 2 results showed that 5 articles were of high quality, 9 of medium quality, 4 of low quality, and 3 of extremely low quality. The most problematic items were as follows: the list of excluded documents was not provided; the sources of funding for each study were not reported; and the research methods were not determined before implementation. PRISMA scale had an average score of(20.38±1.43) points, less than 22 points for 15 articles, with certain reporting defects. The GRADE system suggested that the quality of the evidence for the 30 outcome indicators was low or very low. The most important factors leading to degrading was the limitation, followed by publication bias and inconsistency. The results showed that as compared with conventional Western medicine, TCM oral or enema treatment for mild to moderate ulcerative colitis had better clinical efficacy and safety. Due to the quality limitations of the included studies, it is necessary to further strengthen the top-level design and follow the scientific research paradigm to provide a higher level of evidence for the clinical evidence-based decision-making of TCM.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Medicina Tradicional Chinesa , Humanos , Projetos de Pesquisa , Resultado do Tratamento
8.
Phys Chem Chem Phys ; 20(44): 27970-27974, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30382262

RESUMO

Based on first-principles calculations, we study the hydrogen evolution reaction (HER) on metal-free C2N and make efforts to improve its catalytic performance. At H* coverages (θ) of 3/6 and 4/6, the free energy of hydrogen adsorption (ΔGH*) is 0.10 eV and 0.07 eV, respectively, which is competitive with the precious catalyst Pt. Moreover, ΔGH* can be modulated to zero under a tensile strain, and the strength of the strain depends on the H concentration. Experimentally, it is possible to achieve a strain of around 2% through coupling C2N with graphene, and the HER performance of the hybrids would be generally enhanced. Moreover, the catalytic activity of the hybrids is tunable via electron and hole doping of graphene. In the strong H binding cases (θ = 1/6), anchoring Mn atoms into C2N exhibits a perfect catalytic property with ΔGH* of -0.04 eV. Therefore, C2N-based catalysts are expected to be easily synthesized and highly active catalysts for the HER. These findings may shed light on replacing Pt by metal-free or/and non-precious metal counterparts.

9.
Phys Chem Chem Phys ; 20(5): 3608-3613, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29340382

RESUMO

The application of the reported armchair transition-metal dichalcogenide (MoS2, MoTe2, MoSTe and WS2, etc.) nanotube is hindered for the optoelectronic devices due to the indirect band gap. By using first-principles calculations, the electronic structures of MoS2-xSex single-wall armchair nanotubes with respect to different diameters are investigated. The MoS2 armchair nanotube exhibits an indirect band gap as a function of nanotube diameters from 10 Å to 50 Å, whereas MoSSe and MoSe2 exhibit a surprising diameter-induced indirect-direct band gap crossover at the diameters of 25 Å and 33 Å, respectively. We also find that the optical properties of MoS2-xSex armchair nanotubes are anisotropic and strongly depend on the diameter.

10.
Phys Chem Chem Phys ; 20(31): 20525-20533, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30046794

RESUMO

Tetragonal Na3PS4 (t-Na3PS4) has been demonstrated as a very promising candidate for a solid-state sodium-ion electrolyte with high Na ionic conductivity at ambient temperature. In this paper, we systematically investigated the Na ionic conductivity in pristine and halogen (F, Cl, Br, and I) doped tetragonal-Na3PS4 superionic conductors using first-principles calculations. The Na ionic conductivity of pristine t-Na3PS4 is calculated to be about 0.01 mS cm-1, while much higher Na ionic conductivities could be achieved by introducing Na ion vacancies via a halogen doping strategy. The calculated Na ionic conductivity of t-Na3PS4 doped with 1.56% Cl is 1.07 mS cm-1 at ambient temperature. Among different halogen-doped t-Na3PS4, Br-doped t-Na3PS4 shows the lowest activation energy and the highest Na ionic conductivity, which reaches 2.37 mS cm-1 at 300 K. The low activation energy and high Na ionic conductivity in Br-doped t-Na3PS4 are due to a relatively lower defect binding energy of the defect pair of halogen substitution and a Na ion vacancy. Our results suggest Br-doped t-Na3PS4 may serve as a very promising Na-ion solid-state superionic conductor.

11.
Nano Lett ; 17(8): 5148-5155, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28745511

RESUMO

The strong coupling between crystal structure and mechanical deformation can stabilize low-symmetry phases from high-symmetry phases or induce novel phase transformation in oxide thin films. Stress-induced structural phase transformation in oxide thin films has drawn more and more attention due to its significant influence on the functionalities of the materials. Here, we discovered experimentally a novel stress-induced cubic-to-hexagonal phase transformation in the perovskite nanothin films of barium titanate (BaTiO3) with a special thermomechanical treatment (TMT), where BaTiO3 nanothin films under various stresses are annealed at temperature of 575 °C. Both high-resolution transmission electron microscopy and Raman spectroscopy show a higher density of hexagonal phase in the perovskite thin film under higher tensile stress. Both X-ray photoelectron spectroscopy and electron energy loss spectroscopy does not detect any change in the valence state of Ti atoms, thereby excluding the mechanism of oxygen vacancy induced cubic-to-hexagonal (c-to-h) phase transformation. First-principles calculations show that the c-to-h phase transformation can be completed by lattice shear at elevated temperature, which is consistent with the experimental observation. The applied bending plus the residual tensile stress produces shear stress in the nanothin film. The thermal energy at the elevated temperature assists the shear stress to overcome the energy barriers during the c-to-h phase transformation. The stress-induced phase transformation in perovskite nanothin films with TMT provides materials scientists and engineers a novel approach to tailor nano/microstructures and properties of ferroelectric materials.

12.
Nature ; 464(7290): 881-4, 2010 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-20376147

RESUMO

Atmospheric concentrations of the greenhouse gas nitrous oxide (N(2)O) have increased significantly since pre-industrial times owing to anthropogenic perturbation of the global nitrogen cycle, with animal production being one of the main contributors. Grasslands cover about 20 per cent of the temperate land surface of the Earth and are widely used as pasture. It has been suggested that high animal stocking rates and the resulting elevated nitrogen input increase N(2)O emissions. Internationally agreed methods to upscale the effect of increased livestock numbers on N(2)O emissions are based directly on per capita nitrogen inputs. However, measurements of grassland N(2)O fluxes are often performed over short time periods, with low time resolution and mostly during the growing season. In consequence, our understanding of the daily and seasonal dynamics of grassland N(2)O fluxes remains limited. Here we report year-round N(2)O flux measurements with high and low temporal resolution at ten steppe grassland sites in Inner Mongolia, China. We show that short-lived pulses of N(2)O emission during spring thaw dominate the annual N(2)O budget at our study sites. The N(2)O emission pulses are highest in ungrazed steppe and decrease with increasing stocking rate, suggesting that grazing decreases rather than increases N(2)O emissions. Our results show that the stimulatory effect of higher stocking rates on nitrogen cycling and, hence, on N(2)O emission is more than offset by the effects of a parallel reduction in microbial biomass, inorganic nitrogen production and wintertime water retention. By neglecting these freeze-thaw interactions, existing approaches may have systematically overestimated N(2)O emissions over the last century for semi-arid, cool temperate grasslands by up to 72 per cent.


Assuntos
Criação de Animais Domésticos , Animais Domésticos/metabolismo , Ecossistema , Óxido Nitroso/análise , Óxido Nitroso/metabolismo , Microbiologia do Solo , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/estatística & dados numéricos , Animais , Atmosfera/química , Biomassa , China , Clima Desértico , Congelamento , Efeito Estufa , Nitrogênio/metabolismo , Plantas/metabolismo , Poaceae/metabolismo , Estações do Ano , Neve , Solo/análise , Água/análise , Água/metabolismo
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 18(3): 243-6, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26975823

RESUMO

OBJECTIVE: To investigate the association of two single-nucleotide polymorphisms (SNPs) in IL1R1 gene (rs1558641 and rs949963) with the susceptibility to asthma in children from Central China. METHODS: A case-control study was performed in the asthma group and the control group, consisting of 208 children with asthma and 223 normal children from Central China, respectively. The genotypes of two SNPs in IL1R1 gene, rs1558641 and rs949963, were identified using polymerase chain reaction-restriction fragment length polymorphism. The serum level of IL1R1 was determined by enzyme-linked immunosorbent assay. RESULTS: There were no significant differences in genotype and allele frequencies of rs1558641 between the asthma and control groups. In terms of rs949963, the frequencies of GG genotype and alleles were significantly higher in the asthma group than in the control group (P<0.05). The asthma group had a significantly higher serum level of IL1R1 than the control group (P=0.011). Moreover, the serum level of IL1R1 was significantly higher in patients with GG genotype than in those with AA or AG genotype for rs949963 (P=0.028). CONCLUSIONS: IL1R1 SNP rs949963 is associated with the susceptibility to asthma in children from Central China and may increase the serum expression of IL1R1.


Assuntos
Asma/genética , Polimorfismo de Nucleotídeo Único , Receptores Tipo I de Interleucina-1/genética , Alelos , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Masculino
14.
Phys Chem Chem Phys ; 17(37): 23897-908, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26307461

RESUMO

Phase field modelling and thermodynamic analysis are employed to investigate depolarization and compression induced large negative and positive electrocaloric effects (ECEs) in ferroelectric tetragonal crystalline nanoparticles. The results show that double-hysteresis loops of polarization versus electric field dominate at temperatures below the Curie temperature of the ferroelectric material, when the mechanical compression exceeds a critical value. In addition to the mechanism of pseudo-first-order phase transition (PFOPT), the double-hysteresis loops are also caused by the abrupt rise of macroscopic polarization from the abc phase to the c phase or the sudden fall of macroscopic polarization from the c phase to the abc phase when the temperature increases. This phenomenon is called the electric-field-induced-pseudo-phase transition (EFIPPT) in the present study. Similar to the two types of PFOPTs, the two types of EFIPPTs cause large negative and positive ECEs, respectively, and give the maximum absolute values of negative and positive adiabatic temperature change (ATC ΔT). The temperature associated with the maximum absolute value of negative ATC ΔT is lower than that associated with the maximum positive ATC ΔT. Both maximum absolute values of ATC ΔTs change with the variation in the magnitude of an applied electric field and depend greatly on the compression intensity.

15.
BMC Public Health ; 14: 1193, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25413667

RESUMO

BACKGROUND: In the 12th Five-Year Plan, the Chinese government set the goal of increasing life expectancy by one year. The purpose of this study is to examine the impact of major causes of death on the life expectancy of the Chinese people between 1950 and 2010 and predict changing trends to identify major issues requiring future attention. METHODS: A continuous database organised by population and death data on diseases by age group between 1950 and 2010 were created from A Province in Eastern China. The diseases were classified into four categories by the International Classification of Diseases-10 (ICD-10): infectious and parasitic diseases, chronic diseases, accidental injuries, and maternal diseases. Potential gains in life expectancy (PGLEs) were applied to reflect the impact on life expectancy caused by deaths from various diseases, by using the cause-eliminated life table. RESULTS: The PGLEs of infectious and parasitic diseases decreased from 15.59 years in 1950, to 0.07 year in 2010, and have remained low since 2000. However, the PGLEs of chronic diseases increased from 8.70 years in 1950, to 13.36 years in 2010, and indicated an increasing future trend. The two opposite trends exhibited a 'scissors-like difference'. The proportion of accidental injuries and maternal diseases in the death spectrum was low. The PGLEs of accidental injuries decreased from 2.95 years in 1950, to 0.86 year in 2010, maintaining a low level, while the PGLEs of maternal diseases dropped from 0.56 to 0.002 year during the same period, approaching zero. CONCLUSIONS: The findings of this study provide useful information, which could contribute to a more effective allocation of public health programmes. In recent years, chronic diseases and accidental injuries have emerged as major factors influencing life expectancy. Primary and secondary prevention actions, such as public education, modification of behaviours, and introduction of safety measures should be emphasised in efforts to promote life expectancy. The morbidity and mortality rates of infectious, parasitic, and maternal diseases should be maintained at low levels.


Assuntos
Causas de Morte , Expectativa de Vida/tendências , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Doenças Transmissíveis/mortalidade , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Mortalidade Materna/tendências , Pessoa de Meia-Idade , Gravidez , Ferimentos e Lesões/mortalidade
16.
J Ovarian Res ; 17(1): 14, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216976

RESUMO

BACKGROUND: For women of childbearing age, the biggest problem caused by polycystic ovary syndrome (PCOS) is infertility, which is mainly caused by anovulation, abnormal follicular development, proliferation of small antral follicles, and cystic follicles. The mechanism underlying its occurrence is not clear. The abnormal proliferation and development of follicles in PCOS patients is a complex process, which is affected by many factors. The objective of this study was to investigate the relationship between the Hippo pathway and follicular development in PCOS, and to further explore this relationship by using the YAP inhibitor verteporfin (VP). METHOD: 30 3-week-old BALB/C female rats were randomly divided into control group (n = 10), DHEA group (n = 10) and DHEA + VP group (n = 10). The morphology of ovary and the degree of follicular development were observed by HE staining, and the expression and location of AMH in ovarian follicles were observed by immunofluorescence. The ovarian reserve function index AMH, cell proliferation index PCNA and the ratio of Hippo pathway related proteins MST, LATS, YAP, P-YAP and P-YAP/YAP were detected by Western blot. RESULTS: After dividing 30 3-week-old female mice into control, dehydroepiandrosterone (DHEA; model of PCOS), and DHEA + VP groups, we found that the number of small follicles increased in the DHEA group compared to the control group. Additionally, in the DHEA group compared to the control group, anti-müllerian hormone (AMH; ovarian reserve index) increased, proliferating cell nuclear antigen (PCNA; cell proliferation index) decreased, and upstream (MST and LATS) and downstream (YAP and p-YAP) proteins in the Hippo pathway increased, though the p-YAP/YAP ratio decreased. VP ameliorated the increases in AMH, MST, LATS, YAP and p-YAP, but did not ameliorate the decrease in the p-YAP/YAP ratio. CONCLUSIONS: This study indicates that the increased small follicles in the ovaries and changes in ovarian reserve and cell proliferation may be closely related to Hippo pathway activation. This suggests that the Hippo pathway may be an important pathway affecting the proliferation and development of follicles and the occurrence of PCOS.


Assuntos
Síndrome do Ovário Policístico , Humanos , Feminino , Ratos , Animais , Camundongos , Síndrome do Ovário Policístico/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Via de Sinalização Hippo , Camundongos Endogâmicos BALB C , Hormônio Antimülleriano/metabolismo , Desidroepiandrosterona/farmacologia
17.
Adv Healthc Mater ; : e2400704, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38781020

RESUMO

The hybridization of liposome with stem cell membranes is an emerging technology to prepare the nanovehicle with the capacity of disease-responsive targeting. However, the long-term storage of this hybrid liposome has received limited attention in the literature, which is essential for its potential applicability in the clinic. Therefore, the preservation of long-term activity of stem cell-hybrid liposome using freeze-drying is investigated in the present study. Mesenchymal stem cell-hybrid liposome is synthesized and its feasibility for freeze-drying under different conditions is examined. Results reveal that pre-freezing the hybrid liposome at -20 °C in Tris buffer solution (pH 7.4) containing 10% trehalose can well preserve the liposomal structure for at least three months. Notably, major membrane proteins on the hybrid liposome are protected in this formulation and CXCR4-associated targeting capacity is maintained both in vitro and in vivo. Consequently, the hybrid liposome stored for three months demonstrates a comparable tumor inhibition as the fresh-prepared one. The present study provides the first insights into the long-term storage of stem cell hybrid liposome using lyophilization, which may make an important step forward in enhancing the long-term stability of these promising biomimetic nanovehicle and ease the logistics and the freeze-storage in the potential clinical applications.

18.
Redox Rep ; 29(1): 2377870, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39010730

RESUMO

OBJECTIVES: To observe the CISD2 expression among PCOS patients and to explore its profound impact on the follicular microenvironment. Moreover, we want to elucidate the intricate mechanistic contribution of CISD2 to the onset and progression of PCOS. METHODS: Oxidase NOX2, mitophagy-related proteins, and CISD2 were detected by WB. The changes in mitochondrial structure and quantity were observed by transmission electron microscopy. Mitochondrial and lysosome colocalization was used to detect the changes of mitophagy. MDA kit, GSH and GSSG Assay kit and ROS probe were used to detect oxidative stress damage. RESULTS: We found that CISD2, mitophagy and oxidase in the GCs of PCOS patients were significantly increased. Testosterone stimulation leads to the increase of oxidase, mitophagy, and CISD2 in KGN cells. CISD2 inhibition promoted the increase of mitophagy, and the activation of mitochondria-lysosome binding, while alleviating the oxidative stress. CONCLUSIONS: Inhibition of CISD2 can improve the occurrence of oxidative stress by increasing the level of mitophagy, thus affecting the occurrence and development of PCOS diseases.


Assuntos
Mitofagia , Estresse Oxidativo , Síndrome do Ovário Policístico , Humanos , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Feminino , Mitofagia/efeitos dos fármacos , Mitofagia/fisiologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Adulto , Microambiente Celular/fisiologia
19.
Front Plant Sci ; 15: 1297468, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38379943

RESUMO

Water shortage seriously restricts the development of grassland agriculture in arid land and dramatically impacts alfalfa (Medicago sativa L.) quality content and hay yield. Reasonable irrigation methods have the potential to enhance the alfalfa quality content, hay yield, and thus quality yield. Whether partial root-zone drying subsurface drip irrigation (PRDSDI) improves the alfalfa quality yield, quality content, and hay yield is still unknown compared with conventional subsurface drip irrigation (CSDI). The effects of PRDSDI compared with that of CSDI and the interaction with irrigation volume (10 mm/week, 20 mm/week, and 30 mm/week) on the alfalfa quality yield were investigated in 2017-2018 and explained the change in quality yield with the alfalfa quality content and hay yield. Here, the results showed that PRDSDI did not increase the alfalfa quality yield in 2 years. PRDSDI significantly increased acid detergent fiber by 13.3% and 12.2% in 2018 with 10-mm and 20-mm irrigation volumes and neutral detergent fiber by 16.2%, 13.2%, and 12.6% in 2017 with 10-mm, 20-mm, and 30-mm irrigation volumes, respectively. PRDSDI significantly decreased the crude protein by 5.4% and 8.4% in 2018 with 10-mm and 20-mm irrigation volumes and relative feed value by 15.0% with 20-mm irrigation volume in 2017 and 9.8% with 10-mm irrigation volume in 2018, respectively. In addition, PRDSDI significantly increased the alfalfa average hay yield by 49.5% and 59.6% with 10-mm and 20-mm irrigation volumes in 2018, respectively. Our results provide a counterexample for PRDSDI to improve crop quality. Although there was no significant improvement in average quality yield by PRDSDI, the positive impact of average hay yield on quality yield outweighed the negative impact of quality content. Thus, it has the potential to improve quality yields. The novel findings regarding the effects of PRDSDI on quality yield are potentially favorable for the forage feed value in water-limited areas.

20.
Autophagy ; 20(6): 1314-1334, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38174993

RESUMO

Accumulating evidence suggests that cancer-associated fibroblast (CAF) macroautophagy/autophagy is crucial in tumor development and may be a therapeutic target for pancreatic ductal adenocarcinoma (PDAC). However, the role of CAF autophagy during immune surveillance and cancer immunotherapy is unclear. The present study revealed that the inhibition of CAF autophagy suppresses in vivo tumor development in immune-deficient xenografts. This deletion compromises anti-tumor immunity and anti-tumor efficacy both in vitro and in vivo by upregulating CD274/PDL1 levels in an immune-competent mouse model. A block in CAF autophagy reduced the production of IL6 (interleukin 6), disrupting high desmoplastic TME and decreasing USP14 expression at the transcription level in pancreatic cancer cells. We further identify USP14 as the post-translational factor responsible for downregulating CD274 expression by removing K63 linked-ubiquitination at the K280 residue. Finally, chloroquine diphosphate-loaded mesenchymal stem cell (MSC)-liposomes, by accurately targeting CAFs, inhibited CAF autophagy, improving the efficacy of immunochemotherapy to combat pancreatic cancer.Abbreviation: AIR: adaptive immune resistance; ATRA: all-trans-retinoicacid; CAF: cancer-associated fibroblast; CD274/PDL1: CD274 molecule; CM: conditioned medium; CQ: chloroquine diphosphate; CyTOF: Mass cytometry; FGF2/bFGF: fibroblast growth factor 2; ICB: immune checkpoint blockade; IF: immunofluorescence; IHC: immunohistochemistry; IP: immunoprecipitation; MS: mass spectrometer; MSC: mesenchymal stem cell; PDAC: pancreatic ductal adenocarcinoma; TEM: transmission electron microscopy; TILs: tumor infiltrating lymphocytes; TME: tumor microenvironment; USP14: ubiquitin specific peptidase 14.


Assuntos
Autofagia , Fibroblastos Associados a Câncer , Imunoterapia , Neoplasias Pancreáticas , Microambiente Tumoral , Autofagia/efeitos dos fármacos , Animais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/tratamento farmacológico , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/efeitos dos fármacos , Humanos , Camundongos , Imunoterapia/métodos , Microambiente Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral , Imunidade Adaptativa/efeitos dos fármacos , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Antígeno B7-H1/metabolismo , Cloroquina/farmacologia , Cloroquina/uso terapêutico
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