Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 179
Filtrar
1.
Langmuir ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619299

RESUMO

Generally, for adhesive joints, the polar water molecules in humid environments can have a critical effect on the interfacial structures and structural evolution adjacent to the solid substrates. Regarding this, it is still a big challenge to detect and understand the interfacial hygrothermal aging process at the molecular level in real time and in situ. In this study, to trace the interfacial hygrothermal aging process of a classical epoxy formula containing diglycidyl ether of biphenyl A (DGEBA) and 2,2'-(ethylenedioxy) diethylamine (EDDA) with sapphire and fused silica in a typical hygrothermal environment (85 °C and 85% RH), sum frequency generation (SFG) vibrational spectroscopy was used to probe the molecular-level interfacial structural change over the time. The structural evolution dynamics at the buried epoxy/sapphire and epoxy/silica interfaces upon hygrothermal aging were revealed directly in situ. The interfacial delamination during hygrothermal aging was also elucidated from the molecular level. Upon hygrothermal aging, the interfacial CH signals, such as the ones from methyl, methylene, and phenyl groups, decreased significantly and the water OH signals increased substantially, indicating the water molecules had diffused into the interfaces and destroyed the original interactions between the epoxy formula and the substrates. Further analysis indicates that when the integrated signals in the CH range declined to their minimum and leveled off, the interfacial delamination happened. The tensile experiment proved the validity of these spectroscopic experimental results. Our study provides first-hand and molecular-level evidence on a direct correlation between the diffusion of the surrounding water molecules into the interface and the evolution/destruction of the interfacial structures during hygrothermal aging. More importantly, it is proved, SFG can be developed into a powerful tool to noninvasively reveal the local interfacial delamination in real time and in situ under extreme hygrothermal conditions, complemented by the mechanic test.

2.
Aging (Albany NY) ; 162024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38656892

RESUMO

BACKGROUND: Heart failure (HF) has been reported to affect cerebral cortex structure, but the underlying cause has not been determined. This study used Mendelian randomization (MR) to reveal the causal relationship between HF and structural changes in the cerebral cortex. METHODS: HF was defined as the exposure variable, and cerebral cortex structure was defined as the outcome variable. Inverse-variance weighted (IVW), MR-Egger regression and weighted median (WME) were performed for MR analysis; MR-PRESSO and Egger's intercept was used to test horizontal pleiotropy; and "leave-one-out" was used for sensitivity analysis. RESULTS: Fifty-two single nucleotide polymorphisms (SNPs) were defined as instrumental variables (IVs), and there was no horizontal pleiotropy in the IVs. According to the IVW analysis, the OR and 95% CI of cerebral cortex thickness were 0.9932 (0.9868-1.00) (P=0.0402), and the MR-Egger intercept was -15.6× 10-5 (P = 0.7974) and the Global test pval was 0.078. The P-value of the cerebral cortex surface was 0.2205, and the MR-Egger intercept was -34.69052 (P= 0.6984) and the Global Test pval was 0.045. HF had a causal effect on the surface area of the caudal middle frontal lobule (P=0.009), insula lobule (P=0.01), precuneus lobule (P=0.049) and superior parietal lobule (P=0.044). CONCLUSIONS: HF was potentially associated with changes in cortical thickness and in the surface area of the caudal middle frontal lobule, insula lobule, precuneus lobule and superior parietal lobule.

3.
Cardiology ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38648752

RESUMO

INTRODUCTION: Heart failure (HF) is a major global public health concern. The application of machine learning (ML) to identify individuals at high risk and enable early intervention is a promising approach for improving HF prognosis. We aim to systematically evaluate the performance and value of ML models for predicting HF prognosis. METHODS: PubMed, Web of Science, Scopus, and Embase online databases were searched up to April 30, 2023, to identify studies on the use of ML models to predict HF prognosis. HF prognosis primarily encompasses readmission and mortality. The meta-analysis was conducted by MedCalc software. Subgroup analyses include grouping based on types of ML models, time interval, sample sizes, the number of predictive variables, validation methods, whether to conduct hyperparameter optimization and calibration, data set partitioning methods. RESULTS: A total of 31 studies were included. The most common ML models were random forest, boosting, support vector machine, neural network. The area under the receiver operating characteristic curve (AUC) for predicting HF readmission was 0.675 (95% CI 0.651-0.699, P<0.001), and the AUC for predicting HF mortality was 0.790 (95% CI 0.765-0.816, P<0.001). Subgroup analyses revealed that models with the prediction time interval of 1 year, sample sizes =10,000, the number of predictive variables =100, external validation, hyperparameter tuning, calibration adjustment, and data set partitioning using 10-fold cross-validation exhibited favorable performance within their respective subgroups. CONCLUSION: The performance of ML models in predicting HF readmission is relatively poor, while its performance in predicting HF mortality is moderate. The quality of the relevant studies is generally low, it is essential to enhance the predictive capabilities of ML models through targeted improvements in practical applications.

4.
Medicine (Baltimore) ; 103(15): e37722, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608101

RESUMO

RATIONALE: Due to the lack of specificity symptoms and site of onset of castleman disease (CD), it is difficult to diagnose and poses unique challenges for both patients and clinicians, leading to confusion in diagnosis and delays in treatment. To enhance understanding, we present 3 cases of CD treated at our hospital, including a single-center, multicenter, and mixed-type CD. PATIENT CONCERNS: Case 1: A 53-year-old female patient was admitted with a chief complaint of "abdominal pain and fever for 10 days." Marked enlargement of inguinal lymph nodes on both sides was observed. Case 2: A 58-year-old female patient was admitted with the main complaint of "discovering a left lower abdominal mass during a routine checkup for the past 10 days." Upon deep palpation, a palpable mass of approximately 5.0 * 3.0 cm was identified in the left lower abdomen. Case 3: A 40-year-old male patient was admitted with the main complaint of "progressive right upper abdominal and lumbar back pain for over 6 months." Computed tomography examination revealed multiple nodular soft tissue masses between the abdominal aorta and inferior vena cava, with the largest measuring 5.0 * 4.0 cm. DIAGNOSES: Based on the immunohistochemical results, the diagnoses for the 3 patients are as follows: Case 1: Multicentric Castleman's Disease (Mixed Type). Case 2: Pelvic Retroperitoneal Castleman Disease (Hyaline Vascular Type). Case 3: Castleman Disease Multicentric Type. INTERVENTION: Case 1: cyclophosphamide 0.6-1 g + vincristine 2 mg + methylprednisolone 50 mg/5 days. Cyclophosphamide 1 g + prednisone 30-50 mg/5 days. This alternating chemotherapy cycle is repeated every 6 months. Case 2: Laparoscopic pelvic mass excision surgery. Case 3: Surgical excision of the mass. OUTCOMES: Case 1: After a 43-month follow-up, the patient's general symptoms have improved compared to before, but regular chemotherapy is still necessary at present. Case 2: The patient did not take any medication postoperatively, and there has been no evidence of metastasis or recurrence during the 18-month follow-up. Case 3: The patient did not take any medication, and there has been no evidence of metastasis or recurrence during the 21-month follow-up. LESSONS SUBSECTIONS: The lack of specific signs on imaging studies and nonspecific blood tests increases the difficulty of diagnosis. However, tissue biopsy remains a feasible option. Therefore, we recommend conducting thorough examinations for suspected CD patients to reduce misdiagnosis and determine the CD type for effective targeted treatment.


Assuntos
Hiperplasia do Linfonodo Gigante , Feminino , Masculino , Humanos , Pessoa de Meia-Idade , Adulto , Hiperplasia do Linfonodo Gigante/diagnóstico , Dor Abdominal/etiologia , Aorta Abdominal , Biópsia , Ciclofosfamida , Estudos Multicêntricos como Assunto
5.
Drug Des Devel Ther ; 18: 781-799, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500692

RESUMO

Purpose: This study aimed to elucidate the protective mechanism of Traditional Chinese Medicine (TCM) Qifu Yixin formula (QFYXF) to improve heart failure (HF) by promoting ß-arrestin2 (ß-arr2)-mediated SERCA2a SUMOylation. Materials and Methods: The transverse aortic constriction (TAC)-induced HF mice were treated with QFYXF or carvedilol for 8 weeks. ß-arr2-KO mice and their littermate wild-type (WT) mice were used as controls. Neonatal rat cardiomyocytes (NRCMs) were used in vitro. Cardiac function was evaluated by echocardiography and serum NT-proBNP. Myocardial hypertrophy and myocardial fibrosis were assessed by histological staining. ß-arr2, SERCA2a, SUMO1, PLB and p-PLB expressions were detected by Western blotting, immunofluorescence and immunohistochemistry. SERCA2a SUMOylation was detected by Co-IP. The molecular docking method was used to predict the binding ability of the main active components of QFYXF to ß-arr2, SERCA2a, and SUMO1, and the binding degree of SERCA2a to SUMO1 protein. Results: The HF model was constructed 8 weeks after TAC. QFYXF ameliorated cardiac function, inhibiting myocardial hypertrophy and fibrosis. QFYXF promoted SERCA2a expression and SERCA2a SUMOylation. Further investigation showed that QFYXF promoted ß-arr2 expression, whereas Barbadin (ß-arr2 inhibitor) or ß-arr2-KO reduced SERCA2a SUMOylation and attenuated the protective effect of QFYXF improved HF. Molecular docking showed that the main active components of QFYXF had good binding activities with ß-arr2, SERCA2a, and SUMO1, and SERCA2a had a high binding degree with SUMO1 protein. Conclusion: QFYXF improves HF by promoting ß-arr2 mediated SERCA2a SUMOylation and increasing SERCA2a expression.


Assuntos
Insuficiência Cardíaca , Sumoilação , Ratos , Camundongos , Animais , Simulação de Acoplamento Molecular , Miócitos Cardíacos , Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo
7.
Regul Toxicol Pharmacol ; 146: 105542, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070762

RESUMO

Arctii Fructus is the dried ripe fruit of Arctium lappa L. (family Asteraceae) and is in the Chinese pharmacopoeia. Previous research showed that the total lignans from Arctii Fructus (TLAF) have pharmacological activities related to diabetes. This study evaluated the acute and chronic (26 weeks) toxicities associated with oral daily administration of TLAF in Sprague-Dawley (SD) rats. An acute-toxicity test showed that TLAF caused 10% mortality at 3,000 mg/kg × 2 (6-h interval), with toxic symptoms, such as dyspnea and tonic convulsions, indicating potential neurotoxicity. A chronic-toxicity study showed no mortality after administration. The no observed adverse-effect level was 1,800 mg/kg (approximately 54 times higher than the human clinical dose) for 26 weeks of TLAF oral administration in SD rats, with toxicity signs of excessive oral and nasal secretions and moist circumferential hair that recovered after TLAF discontinuation. In the toxicokinetic study, the two main components of TLAF, arctigenin plasma level was positively correlated with dose and tended to accumulate after multiple doses. At 1,800 mg/kg, arctiin plasma level increased and tended to accumulate after multiple doses. These results indicated that TLFA has relatively low toxicity and the potential for clinical treatment of diabetes.


Assuntos
Diabetes Mellitus , Medicamentos de Ervas Chinesas , Lignanas , Ratos , Humanos , Animais , Ratos Sprague-Dawley , Preparações Farmacêuticas , Diabetes Mellitus/tratamento farmacológico , Lignanas/toxicidade
8.
Phys Chem Chem Phys ; 25(48): 33152-33158, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38047897

RESUMO

Magnetic Fe3O4 nanoparticles show promising applications in nanomedicine. However, the saturation magnetization (MS) of Fe3O4 nanoparticles synthesized in laboratory is usually not high enough, which greatly limits their application in drug delivery and magnetic hyperthermia. Here, by accurate hybrid density functional computation, the doping behavior of group III elements (including Al, Ga, and In) and the effects on magnetic and electronic properties are well studied. The results show that the doping behavior depends on the concentration of dopants. Interestingly, appropriate Ga and In doping concentrations can significantly increase the MS of Fe3O4. In addition, the doping of group III elements (Al, Ga and In) into Fe3O4 would not induce any defect states in the band gap but slightly increases the band gap. Our results provide a simple and feasible scheme for increasing the MS of magnetite, which is significant for the applications of Fe3O4 nanoparticles in drug delivery and magnetic hyperthermia.

9.
Nat Commun ; 14(1): 7976, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042900

RESUMO

Infants necessitate vaccinations to prevent life-threatening infections. Our understanding of the infant immune responses to routine vaccines remains limited. We analyzed two cohorts of 2-month-old infants before vaccination, one week, and one-month post-vaccination. We report remarkable heterogeneity but limited antibody responses to the different antigens. Whole-blood transcriptome analysis in an initial cohort showed marked overexpression of interferon-stimulated genes (ISGs) and to a lesser extent of inflammation-genes at day 7, which normalized one month post-vaccination. Single-cell RNA sequencing in peripheral blood mononuclear cells from a second cohort identified at baseline a predominantly naive immune landscape including ISGhi cells. On day 7, increased expression of interferon-, inflammation-, and cytotoxicity-related genes were observed in most immune cells, that reverted one month post-vaccination, when a CD8+ ISGhi and cytotoxic cluster and B cells expanded. Antibody responses were associated with baseline frequencies of plasma cells, B-cells, and monocytes, and induction of ISGs at day 7.


Assuntos
Interferons , Leucócitos Mononucleares , Humanos , Lactente , Leucócitos Mononucleares/metabolismo , Interferons/metabolismo , Vacinação , Perfilação da Expressão Gênica , Inflamação/metabolismo
10.
BMC Surg ; 23(1): 374, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082353

RESUMO

INTRODUCTION: The susceptibility to surgical site occurrence (SSO) is high following ventral hernia repair (VHR) surgery. SSO severely increases the physical and mental burden on patients. The main purpose of this review was to analyze the efficacy of negative pressure wound therapy (NPWT) after open VHR(OVHR) and explore benefits to patients. METHODS: The Cochrane Library, PubMed, and Embase databases were searched from the date of establishment to 15 October 2022. All randomized controlled trials and retrospective cohort studies comparing NPWT with standard dressings after OVHR were included. The Revman 5.4 software recommended by Cochrane and the STATA16 software were used in this meta-analysis. RESULTS: Fifteen studies (involving 1666 patients) were identified and included in the meta-analysis, with 821 patients receiving NPWT. Overall, the incidence rate of SSO in the NPWT group was lower compared to the control group (odds ratio [OR] = 0.44; 95% confidence interval [CI] = 0.21-0.93; I2 = 86%; P = 0.03). The occurrence rate of surgical site infection (SSI; OR = 0.51; 95% CI = 0.38-0.68, P < 0.001), wound dehiscence (OR = 0.64; 95% CI = 0. 43-0.96; P = 0.03), and hernia recurrence (OR = 0.51; 95% CI = 0.28-0.91, P = 0.02) was also lowered. There was no significant difference in seroma (OR = 0.76; 95% CI = 0.54-1.06; P = 0.11), hematoma (OR = 0.53; 95% CI = 0.25-1.11; P = 0.09), or skin necrosis (OR = 0.83; 95% CI = 0.47-1.46; P = 0.52). CONCLUSION: NPWT can effectively decrease the occurrence of SSO, SSI wound dehiscence and hernia recurrence and should be considered following OVHR.


Assuntos
Hérnia Ventral , Tratamento de Ferimentos com Pressão Negativa , Humanos , Deiscência da Ferida Operatória/etiologia , Estudos Retrospectivos , Tratamento de Ferimentos com Pressão Negativa/efeitos adversos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/etiologia , Hérnia Ventral/cirurgia , Herniorrafia/efeitos adversos
11.
medRxiv ; 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37577568

RESUMO

Age is among the strongest risk factors for severe outcomes from SARS-CoV-2 infection. We sought to evaluate associations between age and both mucosal and systemic host responses to SARS-CoV-2 infection. We profiled the upper respiratory tract (URT) and peripheral blood transcriptomes of 201 participants (age range of 1 week to 83 years), including 137 non-hospitalized individuals with mild SARS-CoV-2 infection and 64 uninfected individuals. Among uninfected children and adolescents, young age was associated with upregulation of innate and adaptive immune pathways within the URT, suggesting that young children are primed to mount robust mucosal immune responses to exogeneous respiratory pathogens. SARS-CoV-2 infection was associated with broad induction of innate and adaptive immune responses within the URT of children and adolescents. Peripheral blood responses among SARS-CoV-2-infected children and adolescents were dominated by interferon pathways, while upregulation of myeloid activation, inflammatory, and coagulation pathways was observed only in adults. Systemic symptoms among SARS-CoV-2-infected subjects were associated with blunted innate and adaptive immune responses in the URT and upregulation of many of these same pathways within peripheral blood. Finally, within individuals, robust URT immune responses were correlated with decreased peripheral immune activation, suggesting that effective immune responses in the URT may promote local viral control and limit systemic immune activation and symptoms. These findings demonstrate that there are differences in immune responses to SARS-CoV-2 across the lifespan, including between young children and adolescents, and suggest that these varied host responses contribute to observed differences in the clinical presentation of SARS-CoV-2 infection by age. One Sentence Summary: Age is associated with distinct upper respiratory and peripheral blood transcriptional responses among children and adults with SARS-CoV-2 infection.

12.
J Colloid Interface Sci ; 650(Pt B): 1638-1647, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37494860

RESUMO

Transition metal oxides (TMOs) have received significant consideration. Because of their enormous theoretical capacity, cheap, and less toxicity. Notably, cobalt-based materials hold promises as negative electrode materials for batteries, but they suffer from less electrical conductivity and significant volume changes during operation. In order to address these challenges, sacrificial templating techniques at the nanoscale offer a potential solution for improving the electrochemical stability and rate performance of these materials. More specifically, these tactics have proven popular for designing Li-ion storages. To ascertain the impact of multiple metal ions on the electrochemical capacity, metal organic frameworks (MOFs) derived MCo2O4-MOF (M = Zn, Ni, Cu) were developed. Among these, ZnCo2O4 showed the best electrochemical performance (927.2 mAh g-1 at 0.1 A g-1 after 250 cycles). Furthermore, calculations based on density functional theory (DFT) revealed that ZnCo2O4 had the lowest Li+ adsorption energy, with a minimum value of -1.61 eV. Moreover, this research aims to design controllable nanostructures in order to enhance the design of transition bimetallic oxide composites for energy storage applications.

13.
Microorganisms ; 11(6)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37375077

RESUMO

Microbial spoilage is a major cause of food waste. Microbial spoilage is dependent on the contamination of food from the raw materials or from microbial communities residing in food processing facilities, often as bacterial biofilms. However, limited research has been conducted on the persistence of non-pathogenic spoilage communities in food processing facilities, or whether the bacterial communities differ among food commodities and vary with nutrient availability. To address these gaps, this review re-analyzed data from 39 studies from various food facilities processing cheese (n = 8), fresh meat (n = 16), seafood (n = 7), fresh produce (n = 5) and ready-to-eat products (RTE; n = 3). A core surface-associated microbiome was identified across all food commodities, including Pseudomonas, Acinetobacter, Staphylococcus, Psychrobacter, Stenotrophomonas, Serratia and Microbacterium. Commodity-specific communities were additionally present in all food commodities except RTE foods. The nutrient level on food environment surfaces overall tended to impact the composition of the bacterial community, especially when comparing high-nutrient food contact surfaces to floors with an unknown nutrient level. In addition, the compositions of bacterial communities in biofilms residing in high-nutrient surfaces were significantly different from those of low-nutrient surfaces. Collectively, these findings contribute to a better understanding of the microbial ecology of food processing environments, the development of targeted antimicrobial interventions and ultimately the reduction of food waste and food insecurity and the promotion of food sustainability.

14.
Appl Environ Microbiol ; 89(7): e0045623, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37310210

RESUMO

Pellicles are biofilms that form at the air-liquid interface. We demonstrated that specific strains of Escherichia coli formed pellicles in single cultures when cocultured with Carnobacterium maltaromaticum and E. coli O157:H7 but not with Aeromonas australiensis. Therefore, a combination of comparative genomic, mutational, and transcriptome analyses were applied to identify the unique genes in pellicle formation and investigate gene regulation under different growth phases. Here, we report that pellicle-forming strains do not harbor unique genes relative to non-pellicle-forming strains; however, the expression level of biofilm-related genes differed, especially for the genes encoding curli. Further, the regulatory region of curli biosynthesis is phylogenetically different among pellicle- and non-pellicle-forming strains. The disruption on modified cellulose and regulatory region of curli biosynthesis abolished pellicle formation in strains of E. coli. Besides, the addition of quorum sensing molecules (C4-homoserine lactones [C4-HSL]), synthesized by Aeromonas species, to pellicle formers abolished pellicle formation and implied a role of quorum sensing on pellicle formation. The deletion of autoinducer receptor sdiA in E. coli did not restore pellicle formation when cocultured with A. australiensis but modulated expression level of genes for curli and cellulose biosynthesis, resulting in a thinner layer of pellicle. Taken together, this study identified genetic determinants for pellicle formation and characterized the switching between pellicle to surface-associated biofilm in a dual-species environment, facilitating better understanding of the mechanisms for pellicle formation in E. coli and related organisms. IMPORTANCE To date, most attention has focused on biofilm formation on solid surfaces. By comparison, the knowledge on pellicle formation at the air-liquid interface is more limited and few studies document how bacteria decide on whether to form biofilms on solid surfaces or pellicles at the air-liquid interface to the surface-associated biofilms at the bottom. In this report, we characterized the regulation of biofilm-related genes during pellicle formation and document that interspecies communication via quorum sensing contributes to regulating the switch from pellicle to surface-associated biofilm. The discoveries expand the current view of regulatory cascades associated with pellicle formation.


Assuntos
Aeromonas , Escherichia coli O157 , Biofilmes , Aeromonas/metabolismo , Escherichia coli O157/fisiologia , Genômica , Celulose/metabolismo
15.
Sci Rep ; 13(1): 3709, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879050

RESUMO

It is challenging to distinguish between primary and secondary intracranial hemorrhage (ICH) purely by imaging data, and the two forms of ICHs are treated differently. This study aims to evaluate the potential of CT-based machine learning to identify the etiology of ICHs and compare the effectiveness of two regions of interest (ROI) sketching methods. A total of 1702 radiomic features were extracted from the CT brain images of 238 patients with acute ICH. We used the Select K Best method, least absolute shrinkage, and selection operator logistic regression to select the most discriminable features with a support vector machine to build a classifier model. Then, a ten-fold cross-validation strategy was employed to evaluate the performance of the classifier. From all quantitative CT-based imaging features obtained by two sketch methods, eighteen features were selected respectively. The radiomics model outperformed radiologists in distinguishing between primary and secondary ICH in both the volume of interest and the three-layer ROI sketches. As a result, a machine learning-based CT radiomics model can improve the accuracy of identifying primary and secondary ICH. A three-layer ROI sketch can identify primary versus secondary ICH based on the CT radiomics method.


Assuntos
Hemorragia , Hemorragias Intracranianas , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Aprendizado de Máquina , Neuroimagem , Tomografia Computadorizada por Raios X
16.
Dalton Trans ; 52(3): 806-817, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36594393

RESUMO

A new mesoporous MCM-41-immobilized dichloro(pyridine-2-carboxylato)gold(III) complex [MCM-41-PicAuCl2] was synthesized via an addition reaction of a dichloro(3-hydroxypyridine-2-carboxylato)gold(III) complex to triethoxy(3-isocyanatopropyl)silane, followed by immobilization on MCM-41 and was characterized by different physico-chemical techniques. In the presence of 5 mol% of MCM-41-PicAuCl2, the annulation reaction between anthranils and ynamides proceeded smoothly under mild conditions to afford diverse 6- or 5-formylindoles with high atom economy and good to excellent yields. This new heterogenized gold(III) complex can be easily recovered through a simple filtration process and recycled more than seven times without any apparent loss of its catalytic efficiency.

17.
Trends Microbiol ; 31(1): 107-108, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244922
19.
Circ Res ; 132(2): 187-204, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36583388

RESUMO

BACKGROUND: NOTCH1 pathogenic variants are implicated in multiple types of congenital heart defects including hypoplastic left heart syndrome, where the left ventricle is underdeveloped. It is unknown how NOTCH1 regulates human cardiac cell lineage determination and cardiomyocyte proliferation. In addition, mechanisms by which NOTCH1 pathogenic variants lead to ventricular hypoplasia in hypoplastic left heart syndrome remain elusive. METHODS: CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9 genome editing was utilized to delete NOTCH1 in human induced pluripotent stem cells. Cardiac differentiation was carried out by sequential modulation of WNT signaling, and NOTCH1 knockout and wild-type differentiating cells were collected at day 0, 2, 5, 10, 14, and 30 for single-cell RNA-seq. RESULTS: Human NOTCH1 knockout induced pluripotent stem cells are able to generate functional cardiomyocytes and endothelial cells, suggesting that NOTCH1 is not required for mesoderm differentiation and cardiovascular development in vitro. However, disruption of NOTCH1 blocks human ventricular-like cardiomyocyte differentiation but promotes atrial-like cardiomyocyte generation through shortening the action potential duration. NOTCH1 deficiency leads to defective proliferation of early human cardiomyocytes, and transcriptomic analysis indicates that pathways involved in cell cycle progression and mitosis are downregulated in NOTCH1 knockout cardiomyocytes. Single-cell transcriptomic analysis reveals abnormal cell lineage determination of cardiac mesoderm, which is manifested by the biased differentiation toward epicardial and second heart field progenitors at the expense of first heart field progenitors in NOTCH1 knockout cell populations. CONCLUSIONS: NOTCH1 is essential for human ventricular-like cardiomyocyte differentiation and proliferation through balancing cell fate determination of cardiac mesoderm and modulating cell cycle progression. Because first heart field progenitors primarily contribute to the left ventricle, we speculate that pathogenic NOTCH1 variants lead to biased differentiation of first heart field progenitors, blocked ventricular-like cardiomyocyte differentiation, and defective cardiomyocyte proliferation, which collaboratively contribute to left ventricular hypoplasia in hypoplastic left heart syndrome.


Assuntos
Síndrome do Coração Esquerdo Hipoplásico , Células-Tronco Pluripotentes Induzidas , Humanos , Células Endoteliais/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular/fisiologia , Miócitos Cardíacos/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 288: 122097, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36462321

RESUMO

Chromium (Cr) is an important material, but also one of the most toxic heavy metal pollutants, showing great threat to human health and ecological environment, thus, accurate and rapid detection of Cr3+ has far-reaching significance. In this work, based on the ligand of 2,3,4,5,6-pentafluorobenzoic acid (HPFBA) that does not contains oscillation effect group such as "CH, OH, and NH bond", three rare earth dinuclear cluster of Ln2(PFBA)6(phen)2(H2O)2 (Ln = Tb3+1-Tb, Eu3+1-Eu, Gd3+1-Gd, phen = 1,10-phenanthroline) were obtained. 1-Tb shows excellent stability and luminescence properties. In depth investigation reveals that 1-Tb shows quick detection towards Cr3+ in water through luminescence "turn-off", with extremely short response time of 1.0 min, very low limit of detection (LOD) of 5.2 ppb and no interference from other ions. The LOD value is much lower than the total content of chromium for water in China (15 ppm, GB9078-1996). In the actual environment such as tap water, lake water, human, and serum, 1-Tb shows excellent detection and recovery rate for Cr3+. More interestingly, a fiber based paper of test paper that based on 1-Tb and ordinary filter paper was fabricated, which can probe Cr3+ by visible color changes to the naked eye under UV light.


Assuntos
Metais Terras Raras , Metais , Humanos , Cromo , Água , Limite de Detecção
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...