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1.
Front Microbiol ; 14: 1123444, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37125159

RESUMO

Introduction: Lactation mastitis seriously severely affects the health of lactating females and their infants, yet the underlying causes of clinical lactation mastitis remain unclear. Methods: In this study, we used microbiota-humanized mice as a model to investigate the role of gut microbiota in lactation mastitis. We compared the fecal microbiota of lactation mastitis patients and healthy individuals and conducted fecal microbiota transplantation (FMT) experiments in an antibiotic-pretreated mouse model to test whether gut microbes contribute to human lactation mastitis. Results: Our results showed that gut microbiota diversity was reduced and dysbiosis was present in lactating mastitis patients. FMT from lactation mastitis patients (M-FMT), but not from healthy individuals (H-FMT), to antibiotic-treated mice resulted in lactation mastitis. The inflammation in mice caused by gut microbiota from lactating mastitis patients appears to be pervasive, as hepatocytes from mice that received feces from lactating mastitis patients showed marked swelling. In addition, serum pro-inflammatory factors, including IL-4, IL-17, MPO, IL-6, IL-1ß, and TNF-α, were significantly increased in the M-FMT group. The Firmicutes/Bacteroidetes ratio (F/B), a biomarker of gut dysbiosis, was significantly increased in the M-FMT group. At the phylum level, Actinobacteria were significantly increased, and Verrucomicrobia were significantly decreased in the M-FMT group. At the genus level, Ruminococcus and Faecalibacterium were significantly reduced, while Parabacteroides were significantly increased in the feces of both patients with lactation mastitis and M-FMT mice. Moreover, our study revealed an "amplification effect" on microbiota differences and mastitis disease following human-to-mouse FMT. Conclusion: Collectively, our findings demonstrate that the gut microbiota in lactating mastitis patients is dysbiotic and contributes to the pathogenesis of mastitis.

2.
Eur J Clin Nutr ; 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37138099

RESUMO

OBJECTIVE: This study compared the clinical effects of two different lipid emulsions in premature infants with gestational age < 32 weeks (VPI) or birth weight < 1500 g (VLBWI) to provide an evidence-based medicine basis for optimizing intravenous lipid emulsion. METHODS: This was a prospective multicenter randomized controlled study. A total of 465 VPIs or VLBWIs, admitted to the neonatal intensive care unit of five tertiary hospitals in China from March 1, 2021 to December 31, 2021, were recruited. All subjects were randomly allocated into two groups, namely, medium-chain triglycerides/long-chain triglycerides (MCT/LCT) group (n = 231) and soybean oil, medium-chain triglycerides, olive oil, and fish oil (SMOF) group (n = 234). Clinical features, biochemical indexes, nutrition support therapy, and complications were analyzed and compared between the two groups. RESULTS: No significant differences were found in perinatal data, hospitalization, parenteral and enteral nutrition support between the two groups (P > 0.05). Compared with the MCT/LCT group, the incidence of neonates with a peak value of total bilirubin (TB) > 5 mg/dL (84/231 [36.4% vs. 60/234 [25.6%]), a peak value of direct bilirubin (DB) ≥ 2 mg/dL (26/231 [11.3% vs. 14/234 [6.0%]), a peak value of alkaline phosphatase (ALP) > 900 IU/L (17/231 [7.4% vs. 7/234 [3.0%]), and a peak value of triglycerides (TG) > 3.4 mmol/L (13/231 [5.6% vs. 4/234[1.7%]]) were lower in the SMOF group (P < 0.05). Univariate analysis showed that in the subgroup analysis of < 28 weeks, the incidence of parenteral nutrition-associated cholestasis (PNAC) and metabolic bone disease of prematurity (MBDP) were lower in the SMOF group (P = 0.043 and 0.029, respectively), whereas no significant differences were present in the incidence of PNAC and MBDP between the two groups at > 28 weeks group (P = 0.177 and 0.991, respectively). Multivariate logistic regression analysis revealed that the incidence of PNAC (aRR: 0.38, 95% confidence interval [CI]: 0.20-0.70, P = 0.002) and MBDP (aRR: 0.12, 95% CI: 0.19-0.81, P = 0.029) in the SMOF group were lower than that in the MCT/LCT group. In addition, no significant differences were recorded in the incidence of patent ductus arteriosus, feeding intolerance, necrotizing enterocolitis (Bell's stage ≥ 2), late-onset sepsis, bronchopulmonary dysplasia, intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity and extrauterine growth retardation between the two groups (P > 0.05). CONCLUSIONS: The application of mixed oil emulsion in VPI or VLBWI can reduce the risk of plasma TB > 5 mg/dL, DB ≥ 2 mg/dL, ALP > 900 IU/L, and TG > 3.4 mmol/L during hospitalization. SMOF has better lipid tolerance, reduces the incidence of PNAC and MBDP, and exerts more benefits in preterm infants with gestational age < 28 weeks.

3.
Materials (Basel) ; 16(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37176322

RESUMO

Sandstone is widely used a construction and building material. However, its uniaxial tensile strength (UTS) is not adequately understood. To characterize the uniaxial tensile strength of natural sandstone, three groups of specimens were fabricated for four-point bending, uniaxial compressive, and tensile tests. To characterize the evolution of the stress-strain profiles obtained via these tests, representative expressions were developed in terms of normalized strain and strength. The magnitude of the uniaxial tensile strength exceeded that of the four-point bending strength, indicating that the uniaxial tensile strength cannot be represented by the four-point bending strength. The experimental ratio of uniaxial tensile and compression strength (33-41) was underestimated by the empirical expressions reported in the literature. The suggested correction coefficient for the FBS is 0.25. The compressive modulus (Ec) was generally identical to the experimental results published in the literature, whereas the tensile modulus (Et) was overestimated. The experimental modular ratio, Et/Ec, ranged from 0.12 to 0.14; it was not sensitive to Poisson's ratio, but it increased slightly with the compressive modulus. This work can serve as a reference for computing the load-bearing capacity of sandstone components under tension.

4.
J Pharm Biomed Anal ; 231: 115414, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37141677

RESUMO

Radix Astragali (RA) is commonly used in Asian herbal therapy or food supply, and astragalosides and flavonoids are its major components with diverse pharmaceutical effects. To provide new information on the potential cardiovascular benefits of RA administered orally, the bioaccessibility of these compounds with relevant in vitro digestion parameters was determined for four digestion phases (oral, gastric, small and large intestines) by ultrahigh-performance liquid chromatography quadrupole time-of-flight-mass spectrometry (UPLC-Q-TOF/MS). Meanwhile, we compared the effects of digestion products on advanced glycation end products (AGEs)-induced intracellular reactive oxygen species (ROS) levels in a human arterial endothelial cells (HAECs) model, and studied the potential of RA against oxidative stress-related cardiovascular disease. The changes of saponins and flavonoids composition and antioxidant activity after digestion in intestines were mainly due to the astragaloside IV (AS-IV) biosynthesis involving saponins acetyl isomerization and deacetylation, and the flavonoid glycosides converted to aglycone by deglycosylation processes. All these results suggest that acetyl biotransformation of RA in small intestine directly influenced the response to oxidative stress, and might provide a reference for elucidation of the multi-component action after oral RA in cardiovascular health care.


Assuntos
Medicamentos de Ervas Chinesas , Saponinas , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Células Endoteliais/química , Saponinas/química , Medicamentos de Ervas Chinesas/química , Flavonoides/análise , Biotransformação , Digestão
5.
J Cogn Neurosci ; : 1-16, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37172135

RESUMO

Visual perception is closely related to body movements and action, and it is known that processing visual stimuli is facilitated at the hand or at the hand-movement goal. Such facilitation suggests that there may be an attentional process associated with the hands or hand movements. To investigate the underlying mechanisms of visual attention at a hand-movement goal, we conducted 2 experiments to examine whether attention at the hand-movement goal is a process independent from endogenous attention. Endogenous attention is attention that is intentionally focused on a location, feature, or object. We controlled the hand-movement goal and endogenous attention separately to investigate the spatial profiles of the two types of attention. A visual target was presented either at the goal of hand movement (same condition) or at its opposite side (opposite condition) while steady-state visual-evoked potential (SSVEP) was used to estimate the spatial distributions of the facilitation effect from the 2 types of attention around the hand-movement goal and around the visual target through EEG. We estimated the spatial profile of attentional modulation for the hand-movement goal by taking the difference in SSVEP amplitude between conditions with and without hand movement, thereby obtaining the effect of visual endogenous attention alone. The results showed a peak at the hand-movement goal, independent of the location of the visual target where participants intentionally focused their attention (endogenous attention). We also found differences in the spatial extent of attentional modulation. Spatial tuning was narrow around the hand-movement goal (i.e., attentional facilitation only at the goal location) but was broadly tuned around the focus of endogenous attention (i.e., attentional facilitation spreading over adjacent stimulus locations), which was obtained from the condition without hand movement. These results suggest the existence of 2 separate mechanisms, 1 underlying the attention at the hand-movement goal and another underlying endogenous attention.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37165489

RESUMO

BACKGROUND: High altitude pulmonary edema (HAPE) is a serious mountain sickness with certain mortality. Its early diagnosis is very important. However, the mechanism of its onset and progression is still controversial. PURPOSE: This study aimed to analyze the HAPE occurrence and development mechanism and search for prospective biomarkers in peripheral blood. METHODS: The difference genes (DEGs) of the Control group and the HAPE group were enriched by gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and then GSEA analysis was performed. After identifying the immune-related hub genes, QPCR was used to verify and analyze the hub gene function and diagnostic value with single-gene GSEA and ROC curves, and the drugs that acted on the hub gene was found in the CTD database. Immune infiltration and its association with the hub genes were analyzed using CIBERSORT. Finally, WGCNA was employed to investigate immune invasion cells' significantly related gene modules, following enrichment analysis of their GO and KEGG. RESULTS: The dataset enrichment analysis, immune invasion analysis and WGCNA analysis showed that the occurrence and early progression of HAPE were unrelated to inflammation. The hub genes associated with immunity obtained with MCODE algorithm of Cytoscape were JAK2 and B2M. RT-qPCR and ROC curves confirmed that the hub gene B2M was a specific biomarker of HAPE and had diagnostic value, and single-gene GSEA analysis confirmed that it participated in MHC I molecule-mediated antigen presentation ability decreased, resulting in reduced immunity. CONCLUSION: Occurrence and early progression of high altitude pulmonary edema may not be related to inflammation. B2M may be a new clinical potential biomarker for HAPE for early diagnosis and therapeutic evaluation as well as therapeutic targets, and its decrease may be related to reduced immunity due to reduced ability of MCH I to participate in antigen submission.

7.
Small ; : e2303069, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165759

RESUMO

Amination of aryl chlorides by metallaphotocatalysis is highly desired but remains practically challenging. Meanwhile, relying on soluble noble-metal photocatalysts suffers from resource scarcity and structural instability which limit their practical application. Here in, a highly crystalline acetylene-based hydrazone-linked covalent organic framewok-1 (AC-COF-1) is reported that enables metallaphotocatalytic amination of aryl chlorides. The non-planar effect of hydrazone linkage and weak interlayer attraction of acetylene bond are minimized by intralayer hydrogen-bonding. As a result, the COF shows not only improved crystallinity and porosity, but also enhanced optical and electronic properties compared to a COF analog without hydrogen-bonding. Notably, dual AC-COF-1/Ni system affords CN coupling products from broad aryl chloride substrates in excellent yields (up to 99%) and good functional tolerance. Furthermore, AC-COF-1 is recoverable and reusable for seven times photocatalysis cycles. This report demonstrates simple approach to tune the structure-activity relationship in COFs at molecular level.

8.
Int J Rheum Dis ; 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170730

RESUMO

OBJECTIVE: To investigate the clinical characteristics of systemic lupus erythematosus accompanied by autoimmune liver cirrhosis (SLE-ALC) patients and differences from the non-cirrhosis group. METHODS: Forty-three patients with SLE-ALC were enrolled in this study from 2653 patients with SLE in Peking University People's Hospital. A descriptive case-control study was performed between SLE-ALC patients and the entry time-matched non-cirrhosis group. RESULTS: Among the 43 SLE-ALC patients, 41 (95.3%) were female. Eight patients (18.6%) were first found to have cirrhosis and then diagnosed with SLE. Eighteen patients (41.9%) had jaundice and 27 (62.8%) had esophageal and gastric varices. The age of SLE-ALC patients was 51.1 ± 17.2 years, which was significantly older than the non-cirrhosis group (P < 0.001). Lung involvement was more common as initial manifestations in SLE-ALC patients during the SLE course (P=0.027). Compared with the non-cirrhosis group, SLE-ALC patients had worse liver function. A significantly higher rate of hematological system involvement (anemia, leucopenia, and thrombocytopenia) and a higher level of immunoglobulins were observed in SLE-ALC patients (P<0.05). Moreover, SLE-ALC patients displayed a lower positive rate of anti-double-stranded DNA and anti-ribosomal P protein (P<0.05). The most common radiologic manifestations are ascitic fluid (72.1%) and splenomegaly (71.4%) in SLE-ALC patients. Six SLE-ALC patients underwent liver biopsy, and interface hepatitis was present in all patients. CONCLUSIONS: Cirrhosis is rare in SLE patients but is manifested as a unique pattern of clinical features characterized by late-onset age, lung involvement, high immunoglobulins, and impaired liver function.

9.
Soft Matter ; 19(20): 3570-3579, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37159247

RESUMO

The formation and transformation of defects in confined liquid crystals are fascinating fundamental problems in soft matter. Here, we use molecular dynamics (MD) simulations to study ellipsoidal liquid crystals (LCs) confined in a spherical cavity, which significantly affects the orientation and translation of LC molecules near the surface. The liquid-crystal droplet can present the isotropic to smectic-B phase transition through the smectic-A phase, as the number density of the LC molecules increases. We further find the change of LC structure from bipolar to watermelon-striped during the phase transition from smectic-A (SmA) to smectic-B (SmB) phases. Our results reveal the transition from bipolar defects to the inhomogeneous structures with the coexistence of nematic and smectic phases in smectic liquid-crystal droplets. We also study the influence of the sphere size in the range of 10σ0 ≤ Rsphere ≤ 50σ0 on the structural inhomogeneities. It shows a weak dependence on the sphere size. We further focus on how the structures can be affected by the interaction strength εGB-LJ. Interestingly, we find the watermelon-striped structure can be changed into a configuration with four defects at the vertices of a tetrahedron upon increasing the interaction strength. The liquid crystals at a strong interaction strength of εGB-LJ = 10.0ε0 show the two-dimensional nematic phase at the surface. We further present an explanation for the origin of the striped-pattern formation. Our results highlight the potential for using confinement to control these defects and their associated nanostructural heterogeneity.

10.
BMC Pediatr ; 23(1): 250, 2023 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-37210514

RESUMO

BACKGROUND: It is proposed that the development of parenteral nutrition-associated cholestasis (PNAC) was significantly associated with preterm birth, low birth weight, infection, etc.; however, the etiology and pathogenesis of PNAC are not fully understood. Most of the studies examining PNAC-associated risk factors were single-center studies with relatively small sample sizes. OBJECTIVE: To analyze the risk factors associated with PNAC in preterm infants in China. METHODS: This is a retrospective multicenter observational study. Clinical data on the effect of multiple oil-fat emulsions (soybean oil-medium chain triglycerides-olive oil-fish oil, SMOF) in preterm infants were collected from a prospective multicenter randomized controlled study. A secondary analysis was performed in which preterm infants were divided into the PNAC group and the non-PNAC group based on the PNAC status. RESULTS: A total of 465 cases very preterm infants or very low birth weight infants were included in the study in which 81 cases were assigned to the PNAC group and 384 cases were assigned to the non-PNAC group. The PNAC group had a lower mean gestational age, lower mean birth weight, longer duration of invasive and non-invasive mechanical ventilation, a longer duration oxygen support, and longer hospital stay (P < 0.001 for all). The PNAC group had higher respiratory distress syndrome, hemodynamically significant patent ductus arteriosus, necrotizing enterocolitis (NEC) with stage II or higher, surgically treated NEC, late-onset sepsis, metabolic bone disease, and extrauterine growth retardation (EUGR) compared to the non-PNAC group (P < 0.05 for all). In contrast with the non-PNAC group, the PNAC group received a higher maximum dose of amino acids and fat emulsion, more medium/long-chain fatty emulsion, less SMOF, had a longer duration of parenteral nutrition, lower rates of breastfeeding, higher incidence of feeding intolerance (FI), more accumulated days to achieve total enteral nutrition, less accumulated days of total calories up to standard 110 kcal/kg/day and slower velocity of weight growth (P < 0.05 for all). Logistic regression analysis indicated that the maximum dose of amino acids (OR, 5.352; 95% CI, 2.355 to 12.161), EUGR (OR, 2.396; 95% CI, 1.255 to 4.572), FI (OR, 2.581; 95% CI, 1.395 to 4.775), surgically treated NEC (OR, 11.300; 95% CI, 2.127 ~ 60.035), and longer total hospital stay (OR, 1.030; 95% CI, 1.014 to 1.046) were independent risk factors for the development of PNAC. SMOF (OR, 0.358; 95% CI, 0.193 to 0.663) and breastfeeding (OR, 0.297; 95% CI, 0.157 to 0.559) were protective factors for PNAC. CONCLUSIONS: PNAC can be reduced by optimizing the management of enteral and parenteral nutrition and reducing gastrointestinal comorbidities in preterm infants.


Assuntos
Colestase , Nascimento Prematuro , Feminino , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Emulsões/química , Peso ao Nascer , Estudos Prospectivos , Nascimento Prematuro/etiologia , Colestase/etiologia , Colestase/epidemiologia , Nutrição Parenteral/efeitos adversos , Recém-Nascido de muito Baixo Peso , Aminoácidos , Fatores de Risco
11.
Nat Prod Res ; : 1-8, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37234037

RESUMO

Bioassay-guided isolation of the stems of Garcinia paucinervis led to one new adamantane-type polycyclic polyprenylated acylphloroglucinols (PPAPs), (-)-garpauvinin A (1), and four known analogues (2-5). The structure and absolute configuration of 1 was established via spectroscopic techniques and ECD method. All the isolates displayed moderate antiproliferative activity against HL-60, PC-3 and Caco-2 human cancer cell lines with IC50 values ranging from 0.81 to 19.92 µM, and exhibited low toxicity on WPMY-1 normal human cells, showing selectivity between normal and malignant prostate cells. The biosynthetic pathways of the isolated PPAPs were proposed.

12.
Eur J Gastroenterol Hepatol ; 35(6): 619-628, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37115972

RESUMO

Endoscopic retrograde cholangiopancreatography (ERCP) combined with laparoscopic cholecystectomy plays an important role in the treatment of cholecystolithiasis combined with choledocholithiasis; however, there is no unified standard for the interval of ERCP before laparoscopic cholecystectomy. We conducted a literature search, data extraction and meta-analysis on this topic. Twelve articles with 1142 patients were included, including 567 patients in the E-laparoscopic cholecystectomy group (laparoscopic cholecystectomy performed within 72 h after ERCP) and 575 patients in the D-laparoscopic cholecystectomy group (laparoscopic cholecystectomy performed 72 h after ERCP). The results showed that: compared with the D-laparoscopic cholecystectomy group, the duration of cholecystectomy was shorter in the E-laparoscopic cholecystectomy group [weighted mean difference (WMD) = -16.18, 95% confidence interval (CI) (-22.27 to -10.08), P  < 0.00001], and the postoperative hospitalization was shorter [WMD = -1.24, 95% CI (-1.98 to -0.50), P  < 0.0001]. There were fewer complications [odds ratio (OR) = 0.25, 95% CI (0.39-0.62), P  < 0.0001], lower conversion rate [OR = 0.39, 95% CI (0.21-0.71), P  = 0.002], lower high sensitivity C-reactive protein at 3 days after surgery [WMD = -8.76, 95% CI (-12.59 to -4.93), P  < 0.00001], and fewer neutrophils in the ampulla of gallbladder specimen [WMD = -4.21, 95% CI (-4.55 to -3.88), P < 0.00001]. Therefore, in the treatment of cholecystolithiasis combined with choledocholithiasis by laparoscopic cholecystectomy within 72 h after ERCP, the degree of inflammation before and after surgery is less, the operation time and hospital stay are shortened, the postoperative complications and the conversion rate are reduced, which is a more appropriate time for surgery.


Assuntos
Colecistectomia Laparoscópica , Colecistolitíase , Coledocolitíase , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Coledocolitíase/diagnóstico por imagem , Coledocolitíase/cirurgia , Coledocolitíase/complicações , Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/métodos , Colecistolitíase/complicações , Colecistolitíase/cirurgia , Esfinterotomia Endoscópica
13.
J Integr Plant Biol ; 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37097077

RESUMO

Lipid droplet (LD) in vegetative tissues has recently been implicated in environmental responses in plants, but its regulation and its function in stress tolerance are not well understood. Here, we identified a MORN1 gene as a contributor to natural variations of stress tolerance through genome-wide association study in Arabidopsis thaliana. Characterization of its loss of function mutant and natural variants revealed that the MORN1 gene is a positive regulator of plant growth, disease resistance, cold tolerance and heat tolerance. The MORN1 protein is associated with the Golgi and is also partly associated with LD. Protein truncations that disrupt these associations abolished the biological function of the MORN1 protein. Furthermore, the MORN1 gene is a positive regulator of LD abundance, and its role in LD number regulation and stress tolerance is highly linked. Therefore, this study identifies MORN1 as a positive regulator of LD abundance and a contributor to natural variations of stress tolerance. It implicates a potential involvement of Golgi in LD biogenesis and strongly suggests a contribution of LD to diverse processes of plant growth and stress responses. This article is protected by copyright. All rights reserved.

14.
Sci Total Environ ; 882: 163395, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37044335

RESUMO

Rewetting previously drained peatlands restores the critical function of peatlands as long-term carbon storages and sinks currently threatened by climate change and additional human-induced disturbances. Understanding and projecting the restoration process by rewetting, however, currently face a pressing challenge, the lack of consistent and gap-free records of important carbon cycling indicators of peatlands such as the gross primary production (GPP) over long term. In this study, we reconstructed the GPP in a rewetted peatland called Zarnekow (Fluxnet-ID: DE-Zrk) in Germany from 2000 to 2020 by combining long-term satellite observations and limited-term tower-based eddy covariance (EC) measurements based on Random Forest regression models. The R2 between the reconstructed data and EC data was 0.6. The reasonable reconstruction of long-term GPP enabled trend analysis that identified two distinct periods of decreasing/increasing in GPP due to rewetting and droughts. Rewetting in the winter of 2004 and 2005 stabilized GPP after a decreasing period. A drought in 2018 significantly increased GPP, and GPP remained high over the following two years. Furthermore, the month-specific trends show significant seasonality at this site, specifically, an increasing trend over the 21 years in the growing-season months of June to August and a decreasing trend in the other months. The most important variables for satellite-based estimates of GPP at this site include total evapotranspiration, land surface temperature, enhanced vegetation index and near-infrared reflectance vegetation index. Long-term analyses of carbon fluxes through the combination of satellite observations and EC measurements provide crucial insights into the restoration of carbon sequestration functions in rewetted peatlands.

15.
ACS Appl Mater Interfaces ; 15(15): 19241-19249, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37029737

RESUMO

Metal-organic frameworks (MOFs) are promising candidates for the advanced membrane materials based on their diverse structures, modifiable pore environment, precise pore sizes, etc. Nevertheless, the use of supports and large amounts of solvents in traditional solvothermal synthesis of MOF membranes is considered inefficient, costly, and environmentally problematic, coupled with challenges in their scalable manufacturing. In this work, we report a solvent-free space-confined conversion (SFSC) approach for the fabrication of a series of free-standing MOF (ZIF-8, Zn(EtIm)2, and Zn2(BIm)4) membranes. This approach excludes the employment of solvents and supports that require tedious pretreatment and, thus, makes the process more environment-friendly and highly efficient. The free-standing membranes feature a robust and unique architecture, which comprise dense surface layers and highly porous interlayer with large amounts of irregular-shaped micron-scale pore cavities, inducing satisfactory H2/CO2 selectivities and exceptional H2 permeances. The ZIF-8 membrane affords a considerable H2 permeance of 2653.7 GPU with a competitive H2/CO2 selectivity of 17.1, and the Zn(EtIm)2 membrane exhibits a high H2/CO2 selectivity of 22.1 with an excellent H2 permeance (6268.7 GPU). The SFSC approach potentially provides a new pathway for preparing free-standing MOF membranes under solvent-free conditions, rendering it feasible for scale-up production of membrane materials for gas separation.

16.
Biochem Cell Biol ; 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37018819

RESUMO

Atrial structural remodeling takes on a critical significance to the occurrence and maintenance of atrial fibrillation (AF). As revealed by recent data, insulin-like growth factor-1 receptor (IGF-1R) plays a certain role in tissue fibrosis. In this study, the mechanism of IGF-1R in atrial structural remodeling was examined based on in vivo and in vitro experiments. First, cluster analysis of AF hub genes was conducted, and then the molecular mechanism was proposed by which IGF-1R regulates myocardial fibrosis via the PI3K/Akt/FoxO3a pathway. Subsequently, the mentioned mechanism was verified in human cardiac fibroblasts (HCFs) and rats transduced with IGF-1 overexpression type 9 adeno-associated viruses. The results indicated that IGF-1R activation up-regulated collagen Ⅰ protein expression and Akt phosphorylation in HCFs and rat atrium. The administration of LY294002 reversed the above phenomenon, improved the shortening of atrial effective refractory period, and reduced the increased incidence of AF and atrial fibrosis in rats. The transfection of FoxO3a siRNA reduced the anti-fibrotic effect of LY294002 in HCFs. The above data revealed that activation of IGF-1R takes on a vital significance to atrial structural remodeling by facilitating myocardial fibrosis and expediting the occurrence and maintenance of AF through the regulation of the PI3K/Akt/FoxO3a signaling pathway.

17.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1463-1482, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-37005834

RESUMO

Dolomiaea plants are perennial herbs in the Asteraceae family with a long medicinal history. They are rich in chemical constituents, mainly including sesquiterpenes, phenylpropanoids, triterpenes, and steroids. The extracts and chemical constituents of Dolomiaea plants have various pharmacological effects, such as anti-inflammatory, antibacterial, antitumor, anti-gastric ulcer, hepatoprotective and choleretic effects. However, there are few reports on Dolomiaea plants. This study systematically reviewed the research progress on the chemical constituents and pharmacological effects of Dolomiaea plants to provide references for the further development and research of Dolomiaea plants.


Assuntos
Asteraceae , Sesquiterpenos , Triterpenos , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Anti-Inflamatórios , Compostos Fitoquímicos/farmacologia
18.
PNAS Nexus ; 2(4): pgad079, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37065616

RESUMO

Acinetobacter baumannii has been listed as one of the most critical pathogens in nosocomial infections; however, the key genes and mechanisms to adapt to the host microenvironment lack in-depth understanding. In this study, a total of 76 isolates (from 8 to 12 isolates per patient, spanning 128 to 188 days) were longitudinally collected from eight patients to investigate the within-host evolution of A. baumannii. A total of 70 within-host mutations were identified, 80% of which were nonsynonymous, indicating the important role of positive selection. Several evolutionary strategies of A. baumannii to increase its potential to adapt to the host microenvironment were identified, including hypermutation and recombination. Six genes were mutated in isolates from two or more patients, including two TonB-dependent receptor genes (bauA and BJAB07104_RS00665). In particular, the siderophore receptor gene bauA was mutated in multiple isolates from four patients with three MLST types, and all mutations were at amino acid 391 in ligand-binding sites. With 391T or 391A, BauA was more strongly bound to siderophores, which promoted the iron-absorption activity of A. baumannii at acidic or neutral pH, respectively. Through the A/T mutation at site 391 of BauA, A. baumannii displayed two reversible phases to adapt to distinct pH microenvironments. In conclusion, we demonstrated the comprehensive within-host evolutionary dynamics of A. baumannii, and discovered a key mutation of BauA site 391 as a genetic switch to adapt to different pH values, which may represent a model in the pathogen evolutionary adaption of the host microenvironment.

20.
RSC Med Chem ; 14(3): 563-572, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36970143

RESUMO

In the past two decades, photodynamic therapy (PDT) has become an effective method for the treatment of cancer. However, the posttreatment residue of photodynamic agents (PDAs) causes long-term skin phototoxicity. Here, we apply naphthalene-derived, box-like tetracationic cyclophanes, named NpBoxes, to bind to clinically used porphyrin-based PDAs to alleviate their posttreatment phototoxicity by reducing their free content in skin tissues and 1O2 quantum yield. We show that one of the cyclophanes, 2,6-NpBox, could include the PDAs to efficiently suppress their photosensitivity for the generation of reactive oxygen species. A tumour-bearing mouse model study revealed that, when Photofrin, the most widely used PDA in clinic, was administrated at a dose corresponding to the clinical one, 2,6-NpBox of the same dose could significantly suppress its posttreatment phototoxicity on the skin induced by simulated sunlight irradiation, without imposing a negative influence on its PDT efficacy.

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