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1.
Angew Chem Int Ed Engl ; : e202407779, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789391

RESUMO

We introduce a "solution-processing-transformation" strategy, deploying solvent vapor as scaffolds, to fabricate high-quality hydrogen-bonded organic framework (HOF) membranes. This strategy can overcome the mismatch in processing conditions and crystal growth thermodynamics faced during the facile solution processing of the membrane. The procedure includes the vapor-trigged in-situ transformation of dense amorphous supramolecules to crystalline HOF-16, with HOF-11 as the transient state. The mechanism involves a vapor-activated dissolution-precipitation equilibrium shifting and hydrogen bonding-guided molecule rearrangement, elucidated through combined experimental and theoretical analysis. Upon removal of the molecular scaffolds, the resulting HOF-16 membranes showcase significant improvement in hydrogen separation performance over their amorphous counterparts and previously reported HOF membranes. The method's broad applicability is evidenced by successfully extending it to other substrates and HOF structures. This study provides a fundamental understanding of guest-induced ordered supramolecular assembly and paves the way for the advanced manufacture of high-performance HOF membranes for gas separation processes.

2.
Chemistry ; 29(62): e202301608, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37552578

RESUMO

Hierarchical zeolites are highly-desired catalysts in the petrochemical industry due to their shorter diffusion length, faster diffusion rate, and better accessibility to active acid sites compared with conventional zeolites. Herein, we report a simple amino-acid-assisted method to synthesize urchin-like hollow hierarchical FER zeolites with abundant mesopores and macroporous inner cavities. An amino acid (i. e. L-lysine) is used to facilitate the agglomeration of primary gel nanoparticles. The preferential nucleation and crystal growth at the external surfaces together with the lagged crystallization of the inner core of the agglomerates results in the formation of hollow inner cavities after the exhaustion of interior materials. Thanks to the unique hierarchical structure and more accessible acid sites, the hollow hierarchical FER zeolite exhibits improved catalytic performance over the conventional one in the skeletal isomerization of 1-butene to isobutene.

3.
Diabetes Obes Metab ; 25(8): 2084-2095, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37013892

RESUMO

AIM: To evaluate the efficacy and safety of once-weekly (QW) efpeglenatide in people with type 2 diabetes (T2D) suboptimally controlled with oral glucose-lowering drugs and/or basal insulin (BI). MATERIALS AND METHODS: Three phase 3, multicentre, randomized controlled trials compared the efficacy and safety of QW efpeglenatide versus dulaglutide when added to metformin (AMPLITUDE-D), efpeglenatide versus placebo when added to BI ± oral glucose-lowering drugs (AMPLITUDE-L) or metformin ± sulphonylurea (AMPLITUDE-S). All trials were terminated early by the sponsor because of funding rather than safety or efficacy concerns. RESULTS: In AMPLITUDE-D, non-inferiority of efpeglenatide to dulaglutide 1.5 mg was shown in HbA1c reduction from baseline to week 56, least squares mean treatment difference (95% CI): 4 mg, -0.03% (-0.20%, 0.14%)/-0.35 mmol/mol (-2.20, 1.49); 6 mg, -0.08% (-0.25%, 0.09%)/-0.90 mmol/mol (-2.76, 0.96). The reductions in body weight (approximately 3 kg) from baseline to week 56 were similar across all treatment groups. In AMPLITUDE-L and AMPLITUDE-S, numerically greater reduction in HbA1c and body weight were observed at all doses of efpeglenatide than placebo. American Diabetes Association level 2 hypoglycaemia (< 54 mg/dL [< 3.0 mmol/L]) was reported in few participants across all treatment groups (AMPLITUDE-D, ≤ 1%; AMPLITUDE-L, ≤ 10%; and AMPLITUDE-S, ≤ 4%). The adverse events profile was consistent with other glucagon-like peptide-1 receptor agonists (GLP-1 RAs); gastrointestinal adverse events were most frequent in all three studies. CONCLUSIONS: In people with T2D suboptimally controlled with oral glucose-lowering drugs and/or BI, QW efpeglenatide was non-inferior to dulaglutide in terms of HbA1c reduction and showed numerically greater improvements than placebo in glycaemic control and body weight, with safety consistent with the GLP-1 RA class.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Hemoglobinas Glicadas , Glicemia , Ensaios Clínicos Controlados Aleatórios como Assunto , Metformina/efeitos adversos , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Peso Corporal , Glucose/uso terapêutico , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Resultado do Tratamento , Proteínas Recombinantes de Fusão/efeitos adversos
4.
Angew Chem Int Ed Engl ; 62(41): e202310419, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37615859

RESUMO

Zeolites with uniform micropores are important shape-selective catalysts. However, the external acid sites of zeolites have a negative impact on shape-selective catalysis, and the microporosity may lead to serious diffusion limitation. Herein, we report on the direct synthesis of hierarchical hollow STW-type zeolite single crystals with a siliceous exterior. In an alkalinous fluoride medium, the nucleation of highly siliceous STW zeolites takes place first, and the nanocrystals are preferentially aligned on the outer surface of the gel agglomerates to grow into single crystalline shells upon crystallization. The lagged crystallization of the internal Al-rich amorphous gels onto the inner surface of nanocrystalline zeolite shells leads to the formation of hollow cavities in the core of the zeolite crystals. The hollow zeolite single crystals possess a low-to-high aluminum gradient from the surface to the core, resulting in an intrinsic inert external surface, and exhibit superior catalytic performance in toluene methylation reactions.

5.
J Asthma ; 59(5): 1041-1050, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33629923

RESUMO

OBJECTIVE: To identify the factors of family management affecting asthma control status in school-age children with asthma in China. METHOD: The cross-sectional descriptive study was conducted among 139 children with asthma and their parents. The age range of the children was 7 to 14 years of age (Mage = 9.85; 76.26% boys). Eight dimensions (Children Identity, View of Condition, Management Mindset, Parental Mutuality, Parenting Philosophy, Management Approach, Family Focus, Future Expectation) of the Family Management Scale for Children with Asthma (FMSCA) were used as factors of family management. The Asthma Control Test (ACT) and the Children Asthma Control Test (C-ACT) were used to measure the asthma control status of children. A parental questionnaire was used to collect information regarding demographic data of familial socioeconomic status, general data about the child, and medical services status (Follow-Up Plan, received manual of asthma education, attended a lecture on asthma) received from medical institutions. A multivariate ordinal logistic regression model was performed. RESULTS: Factors significantly associated with asthma control were "Follow-Up Plan" (OR, 2.004; 95% CI, 1.009-3.981), "Attended a Lecture on asthma" (OR, 2.586; 95% CI, 1.103-6.066) and two dimensions of the FMSCA, "Children Identity" (OR = 1.133; 95% CI, 1.024-1.254) and "Family Focus" (OR = 1.114; 95% CI, 1.007-1.232). CONCLUSION: This study shows that asthma control status of school-age children in China is related to the parents' views of their child as having a "normal condition" and the parents' satisfaction with the balance between asthma related management and other aspects of family life.


Assuntos
Asma , Adolescente , Asma/terapia , Criança , China , Estudos Transversais , Feminino , Humanos , Masculino , Poder Familiar , Pais
6.
Chem Soc Rev ; 50(3): 1913-1944, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33319885

RESUMO

Crystalline porous materials (CPMs) with uniform and regular pore systems show great potential for separation applications using membrane technology. Along with the research on the synthesis of precisely engineered porous structures, significant attention has been paid to the practical application of these materials for preparation of crystalline porous membranes (CPMBs). In this review, the progress made in the preparation of thin, large area and defect-free CPMBs using classical and novel porous materials and processing is presented. The current state-of-the-art of scalable CPMBs with different nodes (inorganic, organic and hybrid) and various linking bonds (covalent, coordination, and hydrogen bonds) is revealed. The advances made in the scalable production of high-performance crystalline porous membranes are categorized according to the strategies adapted from polymer membranes (interfacial assembly, solution-casting, melt extrusion and polymerization of CPMs) and tailored based on CPM properties (seeding-secondary growth, conversion of precursors, electrodeposition and chemical vapor deposition). The strategies are compared and ranked based on their scalability and cost. The potential applications of CPMBs have been concisely summarized. Finally, the performance and challenges in the preparation of scalable CPMBs with emphasis on their sustainability are presented.

7.
Aesthetic Plast Surg ; 45(6): 2708-2713, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34494129

RESUMO

BACKGROUND: Immediate breast reconstruction has become an important supplement after modified radical mastectomy. The role of preoperative breast reconstruction information has not been widely popularized in China. It may play an important role in choosing immediate breast reconstruction. In this paper, we investigated whether there was an effect of the role of preoperative breast reconstruction information on the difference about choosing immediate breast reconstruction after modified radical mastectomy at signing the operation consent. METHODS: From 2015 January to March 2018, newly admitted 100 patients with breast carcinoma must receive modified radical mastectomy. All these patients' conditions met the requirements of immediate breast reconstruction. Patient age, breast reconstruction cognition, marital status, education, and family economics were recorded. They were randomly classified into two groups (A & B). Preoperative breast reconstruction information was designed and prepared. When it came to signing operation consent, Group A received preoperative breast reconstruction information and Group B did not receive it. We recorded whether they were willing to receive immediate breast reconstruction in different groups. RESULTS: There was no significant difference in patient age, breast reconstruction cognition, marital status, education, and family economics (P > 0.05). Thirty-two patients agreed to receive breast reconstruction and 18 patients did not agree to receive breast reconstruction in Group A when 24 patients agreed to receive breast reconstruction and 26 patients did not agree to receive breast reconstruction in Group B. There was a statistical significance (P < 0.05) between the above two groups. CONCLUSION: Preoperative breast reconstruction information may be a vital role for explaining about choosing immediate breast reconstruction after modified radical mastectomy at signing the operation consent. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Neoplasias da Mama , Mamoplastia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia , Mastectomia Radical Modificada , Estudos Retrospectivos , Resultado do Tratamento
8.
J Med Internet Res ; 22(4): e16768, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32301740

RESUMO

BACKGROUND: The internet allows patients to easily look for health information. However, how Chinese patients with breast cancer use the internet has rarely been investigated, and there is a scarcity of information about the influence of internet use on survival. OBJECTIVE: This observational study aimed to investigate the details of online medical information searching by Chinese patients with breast cancer and to determine whether internet use has any survival benefits. METHODS: Patients who were diagnosed with invasive breast cancer at Peking Union Medical College Hospital between January 2014 and December 2015 were enrolled. We obtained information on their internet-searching behavior and gathered data from the patients' medical and follow-up records. The associations between internet use and other clinic-pathological factors were analyzed. A Cox proportional-hazards model and the Kaplan-Meier method were used for disease-free survival (DFS) analyses. RESULTS: A total of 973 patients with invasive breast cancer who underwent definitive surgery took part in the study. Among them, 477 cases (49.0%) performed web-based breast cancer information searching before the initial treatment. A multivariate logistic regression analysis suggested that web-based breast cancer information searching was significantly associated with younger age (odds ratio [OR] 0.95, 95% CI 0.94-0.97, P<.001), higher education level (OR 1.37, 95% CI 1.01-1.86, P=.04), and breast conserving surgery (OR 1.35, 95% CI 1.04-1.77, P=.03). Baidu (73.4%, 350/477) and WeChat (66.7%, 318/477) were the two most popular online information sources for breast cancer; however, only 44.9% (214/477) felt satisfied with the online information. In contrast to the nonweb searching group, the web-using patients who were satisfied with online information showed significantly improved DFS (hazard ratio 0.26; 95% CI 0.08-0.88, P=.03). CONCLUSIONS: The patients who were most likely to search the internet for breast cancer information were younger and well-educated, and they were more likely to have breast conserving therapy. Web-using patients who were satisfied with the internet information showed significantly improved DFS. Patients should browse credible websites offering accurate and updated information, and website developers should provide high-quality and easy-to-understand information to better meet the needs of patients with breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Comportamento de Busca de Informação/fisiologia , Ferramenta de Busca/métodos , Povo Asiático , Neoplasias da Mama/mortalidade , Feminino , Humanos , Internet , Análise de Sobrevida
9.
Aesthetic Plast Surg ; 44(3): 726-734, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32002578

RESUMO

BACKGROUND: Polyacrylamide hydrogel (PAAG) was once used as an important injection for breast augmentation though it has been banned in China for more than 10 years. Secondary breast deformity after removing PAAG poses a challenging problem. The aim of this article is to introduce types of breast deformity induced by two types of PAAG based on MRI examination and corresponding treatment strategies. METHODS: From 2008 to 2017, 300 patients with the history of injectable PAAG were reviewed. From their medical history, two types of PAAG injections were imported Interfall and domestic Amazingel, 182 patients received Interfall injection and 118 patients received Amazingel injection. MRI was used as a regular examination preoperatively. According to MRI examinations, breast deformities were classified into nodular type, flow type and mixed type. RESULTS: All of them underwent PAAG removal operations. In the 182 patients with Interfall injection: There were only 5 cases of nodular type, 3 cases received immediate breast augmentation and 2 cases received second-stage breast augmentation, and none of cases received breast augmentation; there were 170 cases of flow type, 165 cases received immediate breast augmentation and 5 cases received second-stage breast augmentation, and none of cases received breast augmentation; there were 7 cases of mixed type, 5 cases received immediate breast augmentation, 1 case received second-stage breast augmentation and 1 case did not receive breast augmentation; in the 118 patients with Amazingel injection: There were 111 cases of nodular type, 20 cases received immediate breast augmentation, 51 cases received second-stage breast augmentation and 40 cases did not receive breast augmentation; there were 4 cases of flow type, 2 cases received immediate breast augmentation, 1 case received second-stage breast augmentation and 1 case did not receive breast augmentation; there were 2 cases of mixed type, 1 case received second-stage breast augmentation and 1 case did not receive breast augmentation, and none of cases received immediate breast augmentation . CONCLUSIONS: Breast deformity induced by two types of PAAG can be classified into three types based on MRI examinations, which is very critical for preoperative evaluation and classification. Each type of deformity has its own characteristics, which serves as a guide for whether a first-stage or a second-stage prosthesis implant can be implemented. The proportion of patients who can have breast augmentation in the first or second phase after injection of Interfall is significantly higher than that of patients who have injections of Amazingel. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Assuntos
Doenças Mamárias , Implantes de Mama , Mamoplastia , Resinas Acrílicas , Doenças Mamárias/diagnóstico , Doenças Mamárias/diagnóstico por imagem , Implantes de Mama/efeitos adversos , China , Humanos , Mamoplastia/efeitos adversos , Reoperação , Resultado do Tratamento
10.
Angew Chem Int Ed Engl ; 59(15): 6284-6288, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-31986232

RESUMO

Thin membranes (900 nm) were prepared by direct transformation of infiltrated amorphous precursor nanoparticles, impregnated in a graphene oxide (GO) matrix, into hydroxy sodalite (SOD) nanocrystals. The amorphous precursor particles rich in silanols (Si-OH) enhanced the interactions with the GO, thus leading to the formation of highly adhesive and stable SOD/GO membranes via strong bonding. The cross-linking of SOD nanoparticles with the GO in the membranes promoted both the high gas permeance and enhanced selectivity towards H2 from a mixture containing CO2 and H2 O. The SOD/GO membranes are moisture resistance and exhibit steady separation performance (H2 permeance of about 4900 GPU and H2 /CO2 selectivity of 56, with no degradation in performance during the test of 50 h) at high temperature (200 °C) under water vapor (4 mol %).

11.
Angew Chem Int Ed Engl ; 59(10): 3840-3845, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31833627

RESUMO

Ordered and flexible porous frameworks with solution processability are highly desirable to fabricate continuous and large-scale membranes for the efficient gas separation. Herein, the first microporous hydrogen-bonded organic framework (HOF) membrane has been fabricated by an optimized solution-processing technique. The framework exhibits the superior stability because of the abundant hydrogen bonds and strong π-π interactions. Thanks to the flexible HOF structure, the membrane possesses the unprecedented pressure-responsive H2 /N2 separation performance. Furthermore, the scratched membrane can be healed by the treatment of solvent vapor, achieving the recovery of separation performance.

12.
Molecules ; 21(4): 461, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27070559

RESUMO

This study aimed to investigate the effects of Phlomis umbrosa root on bone growth and growth mediators in rats. Female adolescent rats were administered P. umbrosa extract, recombinant human growth hormone or vehicle for 10 days. Tetracycline was injected intraperitoneally to produce a glowing fluorescence band on the newly formed bone on day 8, and 5-bromo-2'-deoxyuridine was injected to label proliferating chondrocytes on days 8-10. To assess possible endocrine or autocrine/paracrine mechanisms, we evaluated insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3) or bone morphogenetic protein-2 (BMP-2) in response to P. umbrosa administration in either growth plate or serum. Oral administration of P. umbrosa significantly increased longitudinal bone growth rate, height of hypertrophic zone and chondrocyte proliferation of the proximal tibial growth plate. P. umbrosa also increased serum IGFBP-3 levels and upregulated the expressions of IGF-1 and BMP-2 in growth plate. In conclusion, P. umbrosa increases longitudinal bone growth rate by stimulating proliferation and hypertrophy of chondrocyte with the increment of circulating IGFBP-3. Regarding the immunohistochemical study, the effect of P. umbrosa may also be attributable to upregulation of local IGF-1 and BMP-2 expressions in the growth plate, which can be considered as a GH dependent autocrine/paracrine pathway.


Assuntos
Desenvolvimento Ósseo/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Tíbia/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 2/biossíntese , Condrócitos/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Lâmina de Crescimento/efeitos dos fármacos , Lâmina de Crescimento/crescimento & desenvolvimento , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Fator de Crescimento Insulin-Like I/biossíntese , Phlomis/química , Extratos Vegetais/química , Raízes de Plantas/química , Ratos , Tíbia/crescimento & desenvolvimento
13.
Zhonghua Yi Xue Za Zhi ; 94(13): 994-8, 2014 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-24851686

RESUMO

OBJECTIVE: To evaluate the improvement of clinical septic shock guideline of bundle therapy by key points of control strategies and its impact on the outcomes of septic shock patients. METHODS: The quality control team and sepsis steering committee were established to apply key points of control strategies to improve the clinical septic shock guideline of bundle therapy. The time to resuscitation, antibiotics and cultures, the implementation rate of 6-hour resuscitation goals, glucose control and lung protective ventilation strategies were recorded during the plan-do-check-act (PDCA) steps. And the changes of length of ICU stay and hospital mortality were analyzed. RESULTS: Between July 2009 and December 2012, a total of 563 sequential septic shock patients were admitted. Demographics included median age, gender ratio, initial Acute Physiology and Chronic Health Evaluation II (Apache II) score and sources of infection showed no significant differences during this period. Compared with 2009, the time to resuscitation (65.1 ± 10.3 vs 99.7 ± 10.5 min, P < 0.01) , the time to cultures (55.9 ± 5.2 vs 71.5 ± 7.9 min, P < 0.01) and the time to antibiotics (58.1 ± 5.8 vs 152.8 ± 16.1 min, P < 0.01) significantly decreased in 2012. The implementation rate of 6-hour resuscitation goals (68.7% vs 28.7%, P < 0.01) , the implementation rate of glucose control (79.6% vs 40.0%, P < 0.01) and the implementation rate of lung protective ventilation strategies (74.1% vs 51.4%, P = 0.004) improved significantly form 2009 to 2012. The length of ICU stay (7.2 ± 1.5 vs 9.8 ± 2.7 d, P < 0.01) decreased. And hospital mortality decreased from 40.0% in 2009 to 23.1% in 2012 (P = 0.015). CONCLUSION: The key points of control strategies can improve the clinical septic shock guideline of bundle therapy performance so that there are significant decreases of length of ICU stay and hospital mortality of septic shock patients.


Assuntos
Fidelidade a Diretrizes , Choque Séptico/terapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento
14.
J Colloid Interface Sci ; 659: 650-664, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38198942

RESUMO

The simple preparation of mesoporous NiS2//MoS2 composite catalyst through a one-pot solvothermal method is presented. The improvement of the specific surface area (220 m2/g) and the construction of the porous structure are realized by this method in the case of no support. The organics acts as a microscopic binder contribute to uniform stacking of MoS2 with NiS2 clusters. The composite structure including NiS2 and MoS2 was obtained (proved by XRD, XPS, TEM, IR, UV-vis and RAMAN) and changed the microelectronic environment of the active metal surface (DFT calculation). The mesoporous NiS2//MoS2 catalyst (Ni1Mo1-200) showed an excellent hydrodesulfurization performance of dibenzothiophene (DBT conversion: 78 % at 260 °C) and a high ratio of direct desulfurization pathway (SDDS/HYD = 16.6) at a low reaction temperature. By combining the characterization and theoretical calculation results, the advantages of this NiS2//MoS2 composite structure in synergistic catalysis was further confirmed.

15.
Front Cell Dev Biol ; 11: 1090997, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875770

RESUMO

Primary ovarian insufficiency (POI) is an essential cause of young female fertility loss. At present, there are many treatments for primary ovarian insufficiency, but due to the complexity of the pathogenesis of primary ovarian insufficiency, the efficacy still could not be satisfactory. Stem cell transplantation is a feasible intervention protocol for primary ovarian insufficiency. However, its wide application in the clinic is limited by some defects such as tumorigenic and controversial ethical issues. Stem cell-derived extracellular vesicles (EVs) represent an important mode of intercellular communication attracting increasing interest. It is well documented that stem cell-derived extracellular vesicles for primary ovarian insufficiency with exciting therapeutic effects. Studies have found that stem cell-derived extracellular vesicles could improve ovarian reserve, increase the growth of follicles, reduce follicle atresia, and restore hormone levels of FSH and E2. Its mechanisms include inhibiting ovarian granulosa cells (GCs) apoptosis, reactive oxygen species, and inflammatory response and promoting granulosa cells proliferation and angiogenesis. Thus, stem cell-derived extracellular vesicles are a promising and potential method for primary ovarian insufficiency patients. However, stem cell-derived extracellular vesicles are still a long way from clinical translation. This review will provide an overview of the role and the mechanisms of stem cell-derived extracellular vesicles in primary ovarian insufficiency, and further elaborate on the current challenges. It may suggest new directions for future research.

16.
Nanoscale ; 15(7): 3496-3503, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36723054

RESUMO

The emerging two-dimensional (2D) semiconductors hold a promising prospect for sustaining Moore's law benefitting from the excellent device electrostatics with narrowed channel length. Here, the performance limits of sub-5 nm InSe and In2SSe metal-oxide-semiconductor field-effect transistors (MOSFETs) are explored by ab initio quantum transport simulations. The van der Waals heterostructures prepared by assembling different two-dimensional materials have emerged as a new design of artificial materials with promising physical properties. In this study, device performance was investigated utilizing InSe/In2SSe van der Waals heterostructure as the channel material. Both the monolayer and heterostructure devices can scale Moore's law down to 5 nm. A heterostructure transistor exhibits a higher on-state current and faster switching speed compared with isolated monolayer transistors. This work proves that the sub-5 nm InSe/In2SSe MOSFET can satisfy both the low power and high-performance requirements for the international technology roadmap for semiconductors in the next decade and can provide a feasible approach for enhancing device performance.

17.
Cartilage ; : 19476035231207776, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872706

RESUMO

OBJECTIVES: α2-Macroglobulin (A2M) can prevent cartilage degeneration by blocking many types of cartilage-degrading enzymes, but the mechanism remains to be clarified. This study aimed to test that A2M protects against cartilage degeneration by promoting chondrocyte proliferation and cartilage matrix synthesis via inducing proliferating cell nuclear antigen (PCNA). DESIGN: The cartilage degeneration of the anterior cruciate ligament transection (ACLT) model was evaluated by Safranin O-fast green staining, and articular cartilage degeneration was graded using the Osteoarthritis Research Society International (OARSI)-modified Mankin criteria. The chondrocyte proliferation was detected by 5-Bromodeoxyuridinc (BrdU), MTT, and Cell Counting Kit-8 (CCK8) methods. The chondrocyte apoptosis was detected by lactate dehydrogenase (LDH) assay and Annexin PI staining with the flow cytometer. The glycosaminoglycan (sGAG) and aggrecan in culture supernatant were measured by enzyme-linked immunosorbent assay (ELISA). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to analyze the type II collagen and aggrecan mRNA expression. The PCNA protein expression was analyzed by western blot and immunofluorescent staining. RESULTS: A2M can attenuate cartilage degeneration in ACLT rats. The OARSI scores for cartilage degeneration in the A2M group were lower than those in the phosphate-buffered saline (PBS) group. A2M can promote chondrocyte proliferation and inhibit chondrocyte apoptosis, promote the cartilage matrix synthesis in chondrocytes (type II collagen and aggrecan), and culture supernatant (sGAG and aggrecan). At the same time, it also up-regulated the PCNA protein expression in chondrocytes. CONCLUSIONS: A2M can promote chondrocyte proliferation and cartilage matrix synthesis via inducing PCNA expression.

18.
J Orthop Res ; 41(1): 241-248, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35451533

RESUMO

A hallmark of osteoarthritis (OA) is cartilage degeneration, which has been previously correlated with dramatic increases in inflammatory enzymes. Specifically, interleukin-1ß (IL-1ß) and subsequent upregulation of nuclear factor kappa B (NF-κB) is implicated as an important player in the development of posttraumatic osteoarthritis (PTOA). Alpha 2-macroglobulin (A2M) can inhibit this inflammatory pathway, making it a promising therapy for PTOA. Herein, we demonstrate that A2M binds and neutralizes IL-1ß, blocking downstream NF-κB-induced catabolism seen in in vitro. Human chondrocytes (cell line C28) were incubated with A2M protein and then treated with IL-1ß. A2M was labeled with VivoTag™ 680 to localize the protein postincubation. The degree of binding between A2M and IL-1ß was evaluated through immunoprecipitation (IP). Catabolic proteins, including IL-1ß and NF-kB, were detected by Western blot. Pro-inflammatory and chondrocyte-related gene expression was examined by qRT-PCR. VivoTag™ 680-labeled A2M was observed in the cytoplasm of C28 human chondrocytes by fluorescence microscopy. IP experiments demonstrated that A2M could bind IL-1ß. Additionally, western blot analysis revealed that A2M neutralized IL-1ß and NF-κB in a dose-dependent manner. Moreover, A2M decreased levels of MMPs and TNF-α and increased the expression of cartilage protective genes Col2, Type2, Smad4, and aggrecan. Mostly importantly, A2M was shown to directly neutralize IL-1ß to downregulate the pro-inflammatory responses mediated by the NF-kB pathway. These results demonstrate a mechanism by which A2M reduces inflammatory catabolic activity and protects cartilage after joint injury. Further in vivo studies are needed to fully understand the potential of A2M as a novel PTOA therapy.


Assuntos
NF-kappa B , alfa 2-Macroglobulinas Associadas à Gravidez , Humanos , Gravidez , Feminino , Interleucina-1beta , Mediadores da Inflamação , alfa-Macroglobulinas
19.
ACS Appl Mater Interfaces ; 15(33): 39374-39383, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37561889

RESUMO

Increasing the open-circuit voltage (Voc) stands as a critical strategy for further improving the efficiency of organic-inorganic halide perovskite solar cells (PSCs). Lewis basic polymers, such as polymethyl methacrylate (PMMA), are considered as an effective approach to reduce the nonradiative recombination at the perovskite surface and protect the photoactive layer against moisture. However, the insulating nature of PMMA inherently leads to increased series resistance in PSCs. Here, we propose a multifunctional passivation layer (FG-PMMA) composed of fluorinated graphene (FG) and PMMA, offering high conductivity, a good passivation effect, and excellent hole transportation capabilities. The introduction of FG not only reduces the resistance of the PMMA layer but also improves its hydrophobicity. More importantly, we found that fluoride, which acts as a p-type dopant in graphene, can further reduce the nonradiative recombination centers by forming PbF2 with uncoordinated Pb0 at the perovskite/hole transport layer interface. As a result, the introduction of FG-PMMA significantly enhances the photovoltaic performance, with a record-high open-circuit voltage (Voc) of 1.247 V and an average power conversion efficiency of 22.91%, higher than those of PMMA-based devices (20.75%, 1.210 V), as well as increasing the device's moisture stability, with over 90% of the initial efficiency maintained after 1200 h of aging at room temperature and a relative humidity of 35%.

20.
J Chem Theory Comput ; 19(18): 6425-6433, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37709728

RESUMO

Density functional theory (DFT) is a powerful quantum mechanical computational tool to perform electronic structure calculations for materials. Few DFT methods can ensure accuracy and efficiency simultaneously. DFT + U + V is an alternative effective approach to overcome this drawback. However, the accuracy sensitively depends on the self-consistent estimation of the high-dimensional onsite and intersite Hubbard interaction U and V terms. We propose Bayesian optimization using a dropout (BOD) algorithm, one type of active learning method, to optimize U and V terms. The DFT + U + V with U/V obtained by BOD can produce improved electronic properties for diverse bulk materials of comparable quality to the hybrid functionals with lower computational cost compared to the linear response approach. Note that the band gaps calculated by BOD are somewhat different from that of hybrid functionals by simply applying the same U/V parameters as in the case of surface slabs and interfaces, which suggests that the transferability of U/V from the bulk models to slabs and interfaces is not as well as expected. BOD is extended to calculate the U/V parameters for slabs and interfaces and reach similar results as bulk solids. Moreover, we find that the U/V are reasonably transferable between surface slabs and interfaces with different thicknesses under various effects of quantum confinement, which contributes to fast access to the electronic properties of large-scale systems with higher accuracy.

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