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Accurately quantifying the impact of climatic and anthropogenic factors on vegetation change is critical for developing and evaluating ecological management strategies. However, most presented studies typically ignore the climate temporal effects and assume that all pixels are affected by both climate change (CC) and human activities (HA), which often introduce uncertainties. In this study, Leaf area index (LAI), temperature, precipitation, solar radiation, and land cover data from 1982 to 2020 were used to detect and attribute vegetation dynamics in China. We used partial correlation analysis, generalize linear model, trend analysis, and improved RESTREND to analyze the spatiotemporal variation characteristics of vegetation LAI from 1982 to 2020 and to quantify the effects of CC and HA on vegetation dynamics since the implementation of the Grain for Green Project (GGP). The results indicate that significant vegetation greening appeared in most areas (66.2%) between 2000 and 2020. Both CC and HA have positive effects on vegetation greening. In arid and semi-arid regions, precipitation was the primary driver of vegetation change, while in high-latitude areas of southern and southwestern China, temperature was the primary determinant. After considering the temporal effects, the explanatory power of climate variables for vegetation dynamics increased by 4.0% compared to ignoring the temporal effects, accounting for 72.81%. After dividing the pixels into those affected by CC and those affected by both CC and HA, the contribution of HA was decreased from 31.19% to 25.96%. Although the contribution of HA is lower than that of CC, ecological engineering has effectively promoted vegetation greening. These research findings provide scientific data and theoretical basis for ecological environment protection and natural resource management.
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Human immunodeficiency virus-1 (HIV-1) infection disrupts the homeostatic equilibrium between the host and commensal microbes. However, the dynamic changes of plasma commensal viruses and their role in HIV/simian immunodeficiency virus (SIV) pathogenesis are rarely reported. Here, we investigated the longitudinal changes of plasma virome, inflammation levels, and disease markers using an SIV-infected Macaca leonina model. Large expansions of plasma Anelloviridae, Parvoviridae, Circoviridae and other commensal viruses, and elevated levels of inflammation and D-dimer were observed since the chronic phase of SIV infection. Anelloviridae abundance appears to correlate positively with the CD4+ T cell count but negatively with SIV load especially at the acute phase, whereas other commensal viruses' abundances show opposite correlations with the two disease markers. Antiretroviral therapy slightly reduces but does not substantially reverse the expansion of commensal viruses. Furthermore, 1387 primate anellovirus open reading frame 1 sequences of more than 1500 nucleotides were annotated. The data reveal different roles of commensal viruses in SIV pathogenesis.
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Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/sangue , Carga Viral , Viroma/genética , Macaca , Contagem de Linfócito CD4RESUMO
The discoveries of the oncomicrobiome (intratumoral microbiome) and oncomicrobiota (intratumoral microbiota) represent significant advances in tumor research and have rapidly become of key interest to the field. Within tumors, microorganisms such as bacteria, fungi, viruses, and archaea form the oncomicrobiota and are primarily found within tumor cells, immunocytes, and the intercellular matrix. The oncomicrobiome exhibits marked heterogeneity and is associated with tumor initiation, progression, metastasis, and treatment response. Interactions between the oncomicrobiome and the immune system can modulate host antitumor immunity, influencing the efficacy of immunotherapies. Oncomicrobiome research also faces numerous challenges, including overcoming methodological issues such as low target abundance, susceptibility to contamination, and biases in sample handling and analysis methods across different studies. Furthermore, studies of the oncomicrobiome may be confounded by baseline differences in microbiomes among populations driven by both environmental and genetic factors. Most studies to date have revealed associations between the oncomicrobiome and tumors, but very few have established mechanistic links between the two. This review introduces the relevant concepts, detection methods, sources, and characteristics of the oncomicrobiome. We then describe the composition of the oncomicrobiome in common tumors and its role in shaping the tumor microenvironment. We also discuss the current problems and challenges to be overcome in this rapidly progressing field.
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Phototherapy can offer a safe and non-invasive solution against infections, while promoting wound healing. Conventional phototherapeutic devices are bulky and limited to hospital use. To overcome these challenges, we developed a wearable, flexible red and blue LED (r&bLED) patch controlled by a mobile-connected system, enabling safe self-application at home. The patch exhibits excellent skin compatibility, flexibility, and comfort, with high safety under system supervision. Additionally, we synthesized a sprayable fibrin gel (F-gel) containing blue light-sensitive thymoquinone and red light-synergistic NADH. Combined with bLED, thymoquinone eradicated microbes and biofilms within minutes, regardless of antibiotic resistance. Furthermore, NADH and rLED synergistically improved macrophage and endothelial cell mitochondrial function, promoting wound healing, reducing inflammation, and enhancing angiogenesis, as validated in infected diabetic wounds in mice and minipigs. This innovative technology holds great promise for revolutionizing at-home phototherapy for chronic infected wounds.
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Dispositivos Eletrônicos Vestíveis , Cicatrização , Infecção dos Ferimentos , Animais , Cicatrização/efeitos dos fármacos , Camundongos , Infecção dos Ferimentos/terapia , Suínos , Fototerapia/métodos , Humanos , Biofilmes/efeitos dos fármacos , Serviços de Assistência Domiciliar , NAD/metabolismo , Masculino , Benzoquinonas/química , FibrinaRESUMO
Chimeric Antigen Receptor T (CAR-T) cell therapy has significantly advanced in treating B-cell acute lymphoblastic leukemia (B-ALL) and has shown efficacy in managing relapsed B-ALL after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Donor-derived CAR-T cell offer both high efficacy and rapid response. Although promising results exist, current research lacks definitive evidence of long-term survival benefits for patients treated with donor-derived CAR-T therapy. We report the long-term survival of 32 patients with post-transplant relapsed B-ALL treated with donor-derived CD19 CAR-T cell, achieving either complete Remission (CR) or CR with incomplete peripheral blood recovery (CRi). The median follow-up was 42 months, with 2-year overall survival (OS) and event-free survival (EFS) rates of 56.25% and 50.0%, respectively. The 5-year OS and EFS rates were 53.13% and 46.88%, with no new long-term adverse events observed. These findings demonstrate good long-term safety, supporting donor-derived CAR-T cell as a recommended treatment option for relapsed B-ALL patients post-transplantation. Trial registration: https://www.chictr.org.cn/showproj.html?proj=14315 . Registration number: ChiCTR-OOC-16008447.
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Antígenos CD19 , Transplante de Células-Tronco Hematopoéticas , Imunoterapia Adotiva , Humanos , Transplante de Células-Tronco Hematopoéticas/métodos , Adulto , Masculino , Antígenos CD19/imunologia , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/efeitos adversos , Feminino , Adolescente , Adulto Jovem , Criança , Pessoa de Meia-Idade , Transplante Homólogo/métodos , Recidiva , Pré-Escolar , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidade , Receptores de Antígenos Quiméricos/uso terapêutico , Doadores de Tecidos , Taxa de SobrevidaRESUMO
Herein, covalent organic polyrotaxanes (COPRs) were integrated with supermolecule self-assembly and dynamic imine bond formation to act as absorbents that captured radioactive iodine from water. The aromatic building blocks were initially complexed with ß-cyclodextrin (ß-CD) to form pseudorotaxanes, which were then condensed with aromatic tri-aldehyde via mechanical grinding and solvothermal synthesis in sequence. The threading of ß-CD throughout the polymer skeleton effectively reduced the usage of expensive building blocks and significantly lowered the cost, while also remarkably enhancing the skeleton polarity, which is closely related to many special applications. Impressively, the threading of CD improved the water dispersibility of COPRs, which displayed an abnormally high iodine adsorption capacity. This novel synthetic strategy allows the incorporation of mechanically interlocked CDs into porous polymeric materials, which provides access to low-cost preparations of COPRs with a brand new structure for specific applications.
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In response to prevailing challenges encountered in electrical applications, including insufficient mechanical strength, subpar tensile properties, and limited adaptability to dynamic motion environments, we engineered a pioneering hydrogel adhesive. Simultaneously, we presented a novel interpretation of the application of ZnO in hydrogels. Our innovative approach entailed the intertwining of polyvinyl alcohol (PVA) and flexible sodium alginate (SA) double networks (DN) through cross-linking mechanisms, resulting in the formation of a hydrogen-bonding pinned DN hydrogel. This groundbreaking design substantially amplified the cohesive and adhesive properties of the hydrogel, while the incorporation of zinc oxide (ZnO) through modification served to enhance its electrical conductivity. Our hydrogel sensor demonstrated exceptional capabilities in monitoring human motion, adeptly meeting the demands of diverse motion scenarios. Furthermore, meticulous consideration had been given to the influence of perspiration on sensor performance, rendering our sensor exceptionally well-suited for real-world applications.
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Alginatos , Condutividade Elétrica , Hidrogéis , Ligação de Hidrogênio , Álcool de Polivinil , Óxido de Zinco , Alginatos/química , Hidrogéis/química , Álcool de Polivinil/química , Óxido de Zinco/química , HumanosRESUMO
RATIONALE: Polyarteritis nodosa (PAN) is a necrotizing vasculitis that affects small- and medium-sized arteries, presenting with diverse clinical manifestations. It can impact tissues and organs throughout the body and may be life-threatening in severe cases. Common causes of death include cardiac, renal, and gastrointestinal complications or aneurysm rupture. While separate reports of renal aneurysm and intestinal perforation exist, the coexistence of these conditions is rarely documented. This study reports a severe case of PAN complicated by both renal aneurysm and intestinal perforation, aiming to deepen the understanding of this disease, aid in clinical diagnosis and treatment, and improve patient prognosis. PATIENT CONCERNS: The patient presented to the hospital with dorsal foot pain and abdominal pain persisting for more than 4 months, along with pain and discomfort in both lower extremities for over 1 month. INTERVENTIONS: The patient was diagnosed with PAN, renal aneurysm, intestinal perforation, and grade 3 hypertension (high risk). OUTCOMES: After treatment, the patient showed normal temperature and blood pressure, relief from abdominal pain, and disappearance of myalgia and numbness in the lower limbs. Additionally, the renal aneurysm shrank significantly, the intestinal perforation healed, the ileostomy was reduced, and the patient's condition stabilized. LESSONS: The clinical symptoms of PAN mostly lack specificity, and should be distinguished from microscopic polyangiitis and simulated vasculitis. For patients with intestinal perforation similar to this case, tocilizumab treatment may be effective, but further research is needed to confirm it.
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Perfuração Intestinal , Poliarterite Nodosa , Humanos , Poliarterite Nodosa/complicações , Poliarterite Nodosa/diagnóstico , Perfuração Intestinal/etiologia , Perfuração Intestinal/diagnóstico , Aneurisma/etiologia , Aneurisma/complicações , Aneurisma/diagnóstico , Artéria Renal , Masculino , Feminino , Pessoa de Meia-Idade , Dor Abdominal/etiologiaRESUMO
Identification of tumor neoantigens is indispensable for the development of cancer immunotherapies. However, we are still lacking knowledge about the potential neoantigens derived from sequences outside protein-coding regions. Here, we comprehensively characterized the immunopeptidome landscape by integrating multi-omics data in acute myeloid leukemia (AML). Both canonical and non-canonical MHC-associated peptides (MAPs) in AML were identified. We found that the quality and characteristics of ncMAPs are comparable or superior to cMAPs, suggesting ncMAPs are indispensable sources for tumor neoantigens. We further proposed a computational framework to prioritize the neoantigens by integrating additional transcriptome and immunopeptidome in normal tissues. Notably, 6 of prioritized 13 neoantigens were derived from ncMAPs. The expressions of corresponding source genes are highly related to infiltrations of immune cells. Finally, a risk model was developed, which exhibited good performance for clinical prognosis in AML. Our findings expand potential cancer immunotherapy targets and provide in-depth insights into AML treatment, laying a new foundation for precision therapies in AML.
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Antígenos de Neoplasias , Imunoterapia , Leucemia Mieloide Aguda , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/terapia , Humanos , Antígenos de Neoplasias/imunologia , Antígenos de Histocompatibilidade Classe I/imunologiaRESUMO
Cancer progression involves the gradual loss of a differentiated phenotype and the acquisition of progenitor and stem cell-like features, which are potential culprits of immunotherapy resistance. Although the state-of-the-art predictive computational methods have facilitated the prediction of cancer stemness, there remains a lack of efficient resources to accommodate various usage requirements. Here, we present the Cancer Stemness Online, an integrated resource for efficiently scoring cancer stemness potential at both bulk and single-cell levels. This resource integrates eight robust predictive algorithms as well as 27 signature gene sets associated with cancer stemness for predicting stemness scores. Downstream analyses were performed from five distinct aspects: identifying the signature genes of cancer stemness; exploring the associations with cancer hallmarks and cellular states; exploring the associations with immune response and the communications with immune cells; investigating the contributions to patient survival; and performing a robustness analysis of cancer stemness among different methods. Moreover, the pre-calculated cancer stemness atlas for more than 40 cancer types can be accessed by users. Both the tables and diverse visualizations of the analytical results are available for download. Together, Cancer Stemness Online is a powerful resource for scoring cancer stemness and expanding downstream functional interpretation, including immune response and cancer hallmarks. Cancer Stemness Online is freely accessible at http://bio-bigdata.hrbmu.edu.cn/CancerStemnessOnline.
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Neoplasias , Células-Tronco Neoplásicas , Humanos , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/patologia , Neoplasias/imunologia , Neoplasias/genética , Biologia Computacional/métodos , AlgoritmosRESUMO
BACKGROUND: The identification of spotted leaf 50 (spl50), a novel lesion mimic mutant (LMM) in rice, provides critical insights into the mechanisms underlying programmed cell death (PCD) and innate immunity in plants. RESULTS: Based on ethyl methane sulfonate (EMS)-induced mutagenesis, the spl50 mutant mimics hypersensitive responses in the absence of pathogen by displaying spontaneous necrotic lesions after the tillering phase. SPL50, an ARM repeat protein essential for controlling reactive oxygen species (ROS) metabolism and boosting resistance to blast disease, was identified by map-based cloning techniques. This work also demonstrates the detrimental effects of spl50 on photosynthetic efficiency and chloroplast development. The crucial significance of SPL50 in cellular signaling and stress response is shown by its localization to the cytoplasm and constitutive expression in various plant tissues. In light of growing concerns regarding global food security, this study highlights the pivotal role of SPL50 in regulating programmed cell death (PCD) and enhancing the immune response in plants, contributing to strategies for improving crop disease resistance. CONCLUSIONS: The novel identification of the SPL50 gene in rice, encoding an ARM repeat protein, reveals its pivotal role in regulating PCD and innate immune responses independently of pathogen attack.
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Second-harmonic-generation (SHG) switching is an emerging phenomenon with potential applications in bistable storage and optical switches while also serving as a sensitive probe for inversion-symmetry. Temperature-induced disorder-order phase transition has been proven to be a rational design strategy for achieving SHG bi-state switching; however, pressure-sensitive SHG switching via a disorder-order structural transition mechanism is rarely reported and lacks sensitivity and cyclicity as practical switching materials. Herein, we demonstrate the pressure-induced "dynamical disorder-order" phase transition as an effective strategy for triggering SHG and SHG switching in NH4Cl. The "dynamical disorder-order" phase transition of NH4Cl occurring at as low as 1 GPa is confirmed by comprehensive in situ high-pressure XRD, molecular vibrational spectra, and Brillouin scattering spectra. The pressure-induced SHG is responsive to a wide excitation wavelength region (800-1500 nm), and the "off-on" switching is reversible for up to 50 cycles, setting a record for pressure-driven switching materials. It is worth noting that when pressure is further increased to 14 GPa, NH4Cl exhibits another SHG "on-off" switching, which makes it the first triplet SHG "off-on-off" switching material. Molecular dynamics simulations reveal the key role of N-H···Cl hydrogen bonding in the pressure-induced "dynamic disorder-order" mechanism. Finally, we verified that chemical pressure and physical pressure can jointly regulate the SHG switching behavior of NH4X (X = Cl, Br). The pressure-driven "dynamic disorder-order" transition mechanism sheds light on the rational design of multistable SHG switching materials for photoswitches and information storage.
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As one of the most important food crops in the world, rice yield is directly related to national food security. Lodging is one of the most important factors restricting rice production, and the cultivation of rice varieties with lodging resistance is of great significance in rice breeding. The lodging resistance of rice is directly related to the mechanical strength of the stalks. In this paper, we reviewed the cell wall structure, its components, and its genetic regulatory mechanism, which improved the regulatory network of rice stalk mechanical strength. Meanwhile, we analyzed the new progress in genetic breeding and put forward some scientific problems that need to be solved in this field in order to provide theoretical support for the improvement and application of rice breeding.
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Rice (Oryza sativa L.), a fundamental global staple, nourishes over half of the world's population. The identification of the ddt1 mutant in rice through EMS mutagenesis of the indica cultivar Shuhui527 revealed a dwarf phenotype, characterized by reduced plant height, smaller grain size, and decreased grain weight. Detailed phenotypic analysis and map-based cloning pinpointed the mutation to a single-base transversion in the LOC_Os03g04680 gene, encoding a cytochrome P450 enzyme, which results in a premature termination of the protein. Functional complementation tests confirmed LOC_Os03g04680 as the DDT1 gene responsible for the observed phenotype. We further demonstrated that the ddt1 mutation leads to significant alterations in gibberellic acid (GA) metabolism and signal transduction, evidenced by the differential expression of key GA-related genes such as OsGA20OX2, OsGA20OX3, and SLR1. The mutant also displayed enhanced drought tolerance, as indicated by higher survival rates, reduced water loss, and rapid stomatal closure under drought conditions. This increased drought resistance was linked to the mutant's improved antioxidant capacity, with elevated activities of antioxidant enzymes and higher expression levels of related genes. Our findings suggest that DDT1 plays a crucial role in regulating both plant height and drought stress responses. The potential for using gene editing of DDT1 to mitigate the dwarf phenotype while retaining improved drought resistance offers promising avenues for rice improvement.
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Regulação da Expressão Gênica de Plantas , Giberelinas , Mutação , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Giberelinas/metabolismo , Água/metabolismo , Fenótipo , Secas , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismoRESUMO
Accurately determining the adsorption capacity of Longmaxi shale in complex structural areas is crucial for evaluating the shale gas resources in northeastern Chongqing. However, studies on the pore characteristics and methane adsorption capacity of these Longmaxi shales are currently limited. In this paper, we collected core samples from the YDB-1 well in northeastern Chongqing and determined the pore structure and adsorption capacity of the Longmaxi shale using low-pressure gas adsorption and high-temperature, high-pressure methane adsorption experiments, respectively. The results indicate that the adsorption capacity of shale in complex structural areas is significantly positively correlated with the organic matter (OM) content, weakly positively correlated with the quartz content, and weakly negatively correlated with clay minerals. Meanwhile, gas-in-place content is simultaneously controlled by the pressure and temperature of the reservoir, and with increasing depth, the adsorbed gas rapidly increases to a maximum value (at 0.8 km) and then slowly decreases, whereas the free gas continuously increases. Compared with the shale in the stable structural areas, the Longmaxi shale in complex structural areas usually develops OM-hosted pores and intergranular pores of OM and minerals and contains more micropores due to tectonic compression, resulting in a relatively larger specific surface area and adsorption capacity. This is the reason shale in complex structural areas has high development potential. The final result can provide an important basis for the evaluation of the gas content and the optimization of dessert areas in the Lower Paleozoic shale gas in southern China.
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This research was designed to investigate the effects of cadmium on blood cell injury in cadmium-poisoned mice. Twenty mice were randomly divided into two groups: control group and model group. The control group was intraperitoneally injected with normal saline every day and the model group was intraperitoneally injected with 1.4 mg/kg cadmium solution every day. The experimental period was 28 days. The blood of the mice was collected for detection and hematological analysis. The results demonstrated that cadmium increased the number of white blood cells and the number of neutrophils in mice. Cadmium reduced the number of eosinophils, the number of basophils, the number of monocytes, the amount of lymphocytes, the number of red blood cells, the hemoglobin concentration, mean corpusular volume, mean corpusular hemoglobin, mean corpusular hemoglobin concentration, and the number of platelets in mice. In summary, cadmium caused some damage to white blood cells, red blood cells, and platelets in mice, but the direction of damage to different cells was inconsistent. The possible reason for this result is that cadmium damages the generation of blood cells, and the body takes corresponding defense measures.
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The implementation of pretreatment drug-resistance (PDR) surveillance among people living with HIV-1 (PLWH) is a top priority in countries using efavirenz (EFV)/nevirapine (NVP) for first-line ART. In this study, we assessed the prevalence of PDR among PLWH in Shanghai, China during 2017-2021, and to reveal PDR transmission between Shanghai and other regions of China. A total of 5050 PLWH not on ART during 2017-2021 were included. Partial HIV-1 pol sequences were amplified, sequenced, and analysed for drug-resistance mutations (DRMs). Besides, transmission network of PDR variants was inferred using HIV-TRACE. The overall prevalence of PDR was 4.8% (242/5050; 95% CI, 4.2-5.4). Prevalence of NNRTI-associated PDR was 3.9% (95% CI, 3.4-4.5), higher than those of NRTI-associated (0.8%; 95% CI, 0.5-1.1) and PI-associated PDR (0.9%; 95% CI, 0.6-1.2). High prevalence of PDR (especially high-level resistance) to EFV (132/5050, 2.6%) and NVP (137/5050, 2.7%) were found. CRF01_AE (46.0%) was the predominant HIV-1 genotype with any DRMs, followed by CRF55_01B (21.0%), and CRF07_BC (15.1%). Two NRTI-associated (S68G/N/R and T215A/N/S/Y), five NNRTI-associated (V179D/E/T/L, K103N/R/S/T, E138A/G/K, V106M/I/A and Y181C/I) and two PI-associated mutations (M46I/L/V and Q58E) were the most common observed DRMs in PDR patients in Shanghai. The vast majority of S68G occurred in CRF01_AE (45%). M46I/L/V and Q58E showed a relatively high prevalence in CRF01_AE (4.1%) and CRF07_BC (12.6%). Transmission network analyses demonstrated cross-regional transmission links of PDR variants between Shanghai and other regions of China, which was mainly driven by the potential low-level DRM V179D/E. These results provide crucial information for clinical decision making of first-line ART in PLWH with PDR.
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Fármacos Anti-HIV , Farmacorresistência Viral , Infecções por HIV , HIV-1 , Humanos , China/epidemiologia , HIV-1/genética , HIV-1/efeitos dos fármacos , Infecções por HIV/transmissão , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Infecções por HIV/tratamento farmacológico , Masculino , Farmacorresistência Viral/genética , Feminino , Prevalência , Adulto , Pessoa de Meia-Idade , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Mutação , Adulto Jovem , Ciclopropanos , Alcinos , Benzoxazinas/uso terapêutico , Benzoxazinas/farmacologia , Adolescente , Genótipo , Nevirapina/uso terapêutico , Nevirapina/farmacologia , IdosoRESUMO
An effective strategy to improve the proton conductivity of metal-organic frameworks (MOFs) is to regulate the pore size of composite materials. In this work, composite materials of MOF-808@MOG-808-X (X is the mass ratios of MOF-808 to MOG-808) was successfully prepared by grinding and blending. MOF-808@MOG-808-1:2 was optimal for its suitable pore structure, which facilitates the practical construction of hydrogen bonding networks, promotes rapid and stable proton conduction, and enables the proton conductivity, achieving a 1 + 1 > 2 effect. At 353 K and 93% relative humidity (RH), the maximum proton conductivity of MOF-808@MOG-808-1:2 reaches 1.08 × 10-1 S·cm-1. Next, MOF-808@MOG-808-1:2 was blended with chitosan (CS) to obtain composite proton exchange membranes (PEMs), namely, CS@MOF-808@MOG-808-1:2-Y (Y = 5%, 10%, or 15%) with the maximum proton conductivity reaching 1.19 × 10-2 S·cm-1 at 353 K and 93% RH for CS@MOF-808@MOG-808-1:2-10% with additional stability. The conductive mechanisms of the composite materials were revealed by activation energy calculation. This investigation not only proposes a simple grinding-blending method for the development of MOF-doped composite materials for proton conductivity but also provides a producting material basis for future applications of MOFs in proton exchange membrane fuel cells (PEMFCs).
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This research investigated the effect of cadmium on the tissue and cell of kidney of the turtle Mauremys reevesii. Twenty turtles were injected with cadmium at 0, 7.5, 15, 30 mg/kg separately and five turtles were taken in each group at two weeks after exposure. Kidneys were immediately excised and macroscopic pathological changes were observed, then the kidneys were fixed in 4% paraformaldehyde for histopathological examination and fixed in 2.5% (v/v) glutaraldehyde for examination of ultra-structure. The tissues of kidney presented varying degrees of histopathological lesions in cadmium treated turtles by a dose-dependent manner under the light microscope. Under transmission electron microscope, renal tubules cells presented varying degrees of dose-dependent lesions. The results indicated that cadmium can cause cell damages to the kidney, in particular to the mitochondria. Mitochondria can be used as one biomarker in the monitoring of cadmium pollution and its quantitative risk assessments.