Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.324
Filtrar
1.
SAGE Open Med Case Rep ; 12: 2050313X241240097, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559411

RESUMO

Idiopathic multicentric Castleman disease is a rare and complex disease characterized by systemic inflammation, lymphadenopathy, and multiorgan involvement. This case report presents a 66-year-old Chinese man with idiopathic multicenter Castleman disease without significant lymphadenopathy and challenging diagnosis. Patients present with fever, fatigue, loss of appetite, weight loss, and acute kidney injury. Initially, a urinary tract infection was suspected, but despite anti-infective treatment, the patient's symptoms persisted. Lymph node biopsy, although there is no significant lymphadenopathy, confirms idiopathic multicenter Castleman disease. Treatment includes thalidomide, cyclophosphamide, and dexamethasone, as well as supportive measures and infection control. After 8 months of follow-up, the patient's clinical symptoms, inflammatory markers and renal function were significantly improved, and there was no symptomatic recurrence. This case underscores the importance of considering idiopathic multicenter Castleman's disease in patients with persistent fever and systemic inflammation, even in the absence of significant lymphadenopathy. Early identification and accurate diagnosis of idiopathic multicenter Castleman's disease can lead to the initiation of targeted therapy strategies that ultimately yield favorable outcomes.

2.
Med Phys ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558279

RESUMO

BACKGROUND: Cushing's Disease (CD) is a rare clinical syndrome characterized by excessive secretion of adrenocorticotrophic hormone, leading to significant functional and structural brain alterations as observed in Magnetic Resonance Imaging (MRI). While traditional statistical analysis has been widely employed to investigate these MRI changes in CD, it has lacked the ability to predict individual-level outcomes. PURPOSE: To address this problem, this paper has proposed an interpretable machine learning (ML) framework, including model-level assessment, feature-level assessment, and biology-level assessment to ensure a comprehensive analysis based on structural MRI of CD. METHODS: The ML framework has effectively identified the changes in brain regions in the stage of model-level assessment, verified the effectiveness of these altered brain regions to predict CD from normal controls in the stage of feature-level assessment, and carried out a correlation analysis between altered brain regions and clinical symptoms in the stage of biology-level assessment. RESULTS: The experimental results of this study have demonstrated that the Insula, Fusiform gyrus, Superior frontal gyrus, Precuneus, and the opercular portion of the Inferior frontal gyrus of CD showed significant alterations in brain regions. Furthermore, our study has revealed significant correlations between clinical symptoms and the frontotemporal lobes, insulin, and olfactory cortex, which also have been confirmed by previous studies. CONCLUSIONS: The ML framework proposed in this study exhibits exceptional potential in uncovering the intricate pathophysiological mechanisms underlying CD, with potential applicability in diagnosing other diseases.

3.
Hepatobiliary Surg Nutr ; 13(2): 258-272, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38617474

RESUMO

Background: Visceral pain induced by pancreatic cancer seriously affects patients' quality of life, and there is no effective treatment, because the mechanism of its neural circuit is unknown. Therefore, the aim of this study is to explore the main neural circuit mechanism regulating visceral pain induced by pancreatic cancer in mice. Methods: The mouse model of pancreatic cancer visceral pain was established on C57BL/6N mice by pancreatic injection of mPAKPC-luc cells. Abdominal mechanical hyperalgesia and hunch score were performed to assess visceral pain; the pseudorabies virus (PRV) was used to identify the brain regions innervating the pancreas; the c-fos co-labeling method was used to ascertain the types of activated neurons; in vitro electrophysiological patch-clamp technique was used to record the electrophysiological activity of specific neurons; the calcium imaging technique was used to determine the calcium activity of specific neurons; specific neuron destruction and chemogenetics methods were used to explore whether specific neurons were involved in visceral pain induced by pancreatic cancer. Results: The PRV injected into the pancreas was detected in the paraventricular nucleus of the hypothalamus (PVN). Immunofluorescence staining showed that the majority of c-fos were co-labeled with glutamatergic neurons in the PVN. In vitro electrophysiological results showed that the firing frequency of glutamatergic neurons in the PVN was increased. The calcium imaging results showed that the calcium activity of glutamatergic neurons in the PVN was enhanced. Both specific destruction of glutamatergic neurons and chemogenetics inhibition of glutamatergic neurons in the PVN alleviated visceral pain induced by pancreatic cancer. Conclusions: Glutamatergic neurons in the PVN participate in the regulation of visceral pain induced by pancreatic cancer in mice, providing new insights for the discovery of effective targets for the treatment of pancreatic cancer visceral pain.

4.
Pharmacol Biochem Behav ; 239: 173757, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38574898

RESUMO

Depression is a major chronic mental illness worldwide, characterized by anhedonia and pessimism. Exposed to the same stressful stimuli, some people behave normally, while others exhibit negative behaviors and psychology. The exact molecular mechanisms linking stress-induced depressive susceptibility and resilience remain unclear. Connexin 43 (Cx43) forms gap junction channels between the astrocytes, acting as a crucial role in the pathogenesis of depression. Cx43 dysfunction could lead to depressive behaviors, and depression down-regulates the expression of Cx43 in the prefrontal cortex (PFC). Besides, accumulating evidence indicates that inflammation is one of the most common pathological features of the central nervous system dysfunction. However, the roles of Cx43 and peripheral inflammation in stress-susceptible and stress-resilient individuals have rarely been investigated. Thus, animals were classified into the chronic unpredictable stress (CUS)-susceptible group and the CUS-resilient group based on the performance of behavioral tests following the CUS protocol in this study. The protein expression of Cx43 in the PFC, the Cx43 functional changes in the PFC, and the expression levels including interleukin (IL)-1ß, tumor necrosis factor-α, IL-6, IL-2, IL-10, and IL-18 in the peripheral serum were detected. Here, we found that stress exposure triggered a significant reduction in Cx43 protein expression in the CUS-susceptible mice but not in the CUS-resilient mice accompanied by various Cx43 phosphorylation expression and the changes of inflammatory signals. Stress resilience is associated with Cx43 in the PFC and fluctuation in inflammatory signaling, showing that therapeutic targeting of these pathways might promote stress resilience.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38619977

RESUMO

A Gram-stain-negative, non-motile, and slightly halophilic alphaproteobacterium, designated strain EGI FJ00035T, was isolated from enrichment sediment samples of a saline lake in Xinjiang Uygur Autonomous Region, PR China. The taxonomic position of the isolate was determined using the polyphasic taxonomic and phylogenomic analyses. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain EGI FJ00035T formed a distinct clade with 'Chelativorans alearense' UJN715 and 'Chelativorans xinjiangense' lm93 with sequence similarities of 98.44 and 98.22 %, respectively, while sharing less than 96.7 % with other valid type strains. The novel isolate could be distinguished from other species of the genus Chelativorans by its distinct phenotypic, physiological, and genotypic characteristics. Optimal growth of strain EGI FJ00035T occurred on marine agar 2216 at pH 7.0 and 30 °C. The major respiratory quinone was Q-10, while the major fatty acids (>5 %) were C19 : 0 cyclo ω8c, summed feature 8 (C17 : 1 ω6c and/or C17 : 1 ω7c), C16 : 0, C18 : 0, and iso-C17 : 0. The detected polar lipids included diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, unidentified aminophospholipids, unidentified glycolipids, and an unidentified lipid. Based on its genome sequence, the G+C content of strain EGI FJ00035T was 63.2 mol%. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values of strain EGI FJ00035T against related members of the genus Chelativorans were below the thresholds for delineation of a novel species. According our polyphasic taxonomic data, strain EGI FJ00035T represents a new species of the genus Chelativorans, for which the name Chelativorans salis sp. nov. is proposed. The type strain of the proposed novel isolate is EGI FJ00035T (=KCTC 92251T=CGMCC 1.19480T).


Assuntos
Ácidos Graxos , Phyllobacteriaceae , Ácidos Graxos/química , Fosfolipídeos/química , Ubiquinona/química , Filogenia , RNA Ribossômico 16S/genética , Lagos/análise , Composição de Bases , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Análise de Sequência de DNA , China , Phyllobacteriaceae/genética
6.
Nat Prod Res ; : 1-7, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38571336

RESUMO

Rakicidin J (1) and rakicidin K (2), two new cyclic depsipeptides, were isolated from culture broth of Micromonospora chalcea FIM-R150103. Their structures were elucidated by extensive analysis of NMR, HR-ESI-MS, and electronic circular dichroism (ECD) data. The two compounds showed strong cytotoxic activity against human colon carcinoma HCT-8 and human pancreatic cancer PANC-1 cells under normoxic and hypoxic conditions in the range of IC50 values from 0.024 to 0.79 µg/mL. Moreover, compounds 1 and 2 also showed moderate antibacterial activity against ten Gram-positive bacterial strains with MIC values ranging from 4 to more than 32 µg/mL. Structure-activity relationship of these two compounds with a close analogue, rakicidin B1, is also discussed.

7.
Int Breastfeed J ; 19(1): 22, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570781

RESUMO

BACKGROUND: Healthcare providers play important roles in supporting breastfeeding. Although there has been insufficient actual breastfeeding support from healthcare providers in China, little research has been conducted to understand Chinese healthcare providers' perceived barriers to providing breastfeeding support, especially in rural China. This study aims to identify these perceived barriers to providing breastfeeding support in Northwestern rural China. METHODS: This study was conducted during the period from March 2018 to December 2018. Forty-one healthcare providers were recruited through purposive sampling in two rural counties in Northwest China that are in close proximity to each other and share similar demographic features. Participants included obstetrician-gynecologists, midwives, nurses, "village doctors", and township and village maternal and child health workers. Qualitative data were collected through one-on-one in-depth semi-structured interviews and focus group discussions. Transcripts were thematically analyzed. RESULTS: Analysis of interview data resulted in four themes that the participants perceived as barriers to supporting breastfeeding: (1) lack of medical resources, within which inadequate staffing, and lack of financial incentives were discussed, (2) lack of clear and specific responsibility assignment, within which no one takes the lead, and mutual buck-passing were discussed, (3) healthcare providers' lack of relevant expertise, within which lack of knowledge and skills, and low prestige of village healthcare providers were discussed, (4) difficulties in accessing mothers, within which medical equipment shortages reduce services utilization, mothers' housing situation, mothers' mobility, and cultural barriers were discussed. CONCLUSIONS: The study identified HCPs perceived barriers to providing breastfeeding support. Unique to China's Tri-Level Healthcare System, challenges like staffing and financial incentives are hard to swiftly tackle. Recommendations include mHealth enhancement and clarified responsibilities with incentives and tailored training. Further research is crucial to evaluate these strategies in rural Northwestern China and comparable underdeveloped areas nationwide.


Assuntos
Aleitamento Materno , Pessoal de Saúde , Gravidez , Feminino , Criança , Humanos , Pesquisa Qualitativa , Mães , China
8.
Heliyon ; 10(7): e28957, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601682

RESUMO

Background: Cushing disease (CD) is a rare clinical neuroendocrine disease. CD is characterized by abnormal hypercortisolism induced by a pituitary adenoma with the secretion of adrenocorticotropic hormone. Individuals with CD usually exhibit atrophy of gray matter volume. However, little is known about the alterations in topographical organization of individuals with CD. This study aimed to investigate the structural covariance networks of individuals with CD based on the gray matter volume using graph theory analysis. Methods: High-resolution T1-weighted images of 61 individuals with CD and 53 healthy controls were obtained. Gray matter volume was estimated and the structural covariance network was analyzed using graph theory. Network properties such as hubs of all participants were calculated based on degree centrality. Results: No significant differences were observed between individuals with CD and healthy controls in terms of age, gender, and education level. The small-world features were conserved in individuals with CD but were higher than those in healthy controls. The individuals with CD showed higher global efficiency and modularity, suggesting higher integration and segregation as compared to healthy controls. The hub nodes of the individuals with CD were Short insular gyri (G_insular_short_L), Anterior part of the cingulate gyrus and sulcus (G_and_S_cingul-Ant_R), and Superior frontal gyrus (G_front_sup_R). Conclusions: Significant differences in the structural covariance network of patients with CD were found based on graph theory. These findings might help understanding the pathogenesis of individuals with CD and provide insight into the pathogenesis of this CD.

9.
Anal Chem ; 96(16): 6426-6435, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38604773

RESUMO

Sensors designed based on the trans-cleavage activity of CRISPR/Cas12a systems have opened up a new era in the field of biosensing. The current design of CRISPR/Cas12-based sensors in the "on-off-on" mode mainly focuses on programming the activator strand (AS) to indirectly switch the trans-cleavage activity of Cas12a in response to target information. However, this design usually requires the help of additional auxiliary probes to keep the activator strand in an initially "blocked" state. The length design and dosage of the auxiliary probe need to be strictly optimized to ensure the lowest background and the best signal-to-noise ratio. This will inevitably increase the experiment complexity. To solve this problem, we propose using AS after the "RESET" effect to directly regulate the Cas12a enzymatic activity. Initially, the activator strand was rationally designed to be embedded in a hairpin structure to deprive its ability to activate the CRISPR/Cas12a system. When the target is present, target-mediated strand displacement causes the conformation change in the AS, the hairpin structure is opened, and the CRISPR/Cas12a system is reactivated; the switchable structure of AS can be used to regulate the degree of activation of Cas12a according to the target concentration. Due to the advantages of low background and stability, the CRISPR/Cas12a-based strategy can not only image endogenous biomarkers (miR-21) in living cells but also enable long-term and accurate imaging analysis of the process of exogenous virus invasion of cells. Release and replication of virus genome in host cells are indispensable hallmark events of cell infection by virus; sensitive monitoring of them is of great significance to revealing virus infection mechanism and defending against viral diseases.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , MicroRNAs , Sistemas CRISPR-Cas/genética , Técnicas Biossensoriais/métodos , Humanos , MicroRNAs/análise , MicroRNAs/metabolismo , Regulação Alostérica , Proteínas Associadas a CRISPR/metabolismo , Endodesoxirribonucleases/metabolismo , Endodesoxirribonucleases/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Células HEK293
10.
Nurse Educ Pract ; 77: 103976, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38653087

RESUMO

OBJECTIVE: Developing a nursing undergraduate blended teaching quality evaluation tool based on the Context, Input, Process and Product model and evaluating its reliability and validity. BACKGROUND: Blended teaching is a commonly used teaching method in medical education, but there are limited tools available to effectively measure the quality of blended teaching. DESIGN: A Delphi study and cross-sectional study. METHODS: Using the Context, Input, Process and Product model as the theoretical framework, a questionnaire was developed through literature review, expert consultation and pre-survey. From April to July 2023, 448 students from a certain university were selected as the research subjects and the questionnaire was examined for reliability and validity through a survey method. RESULTS: The blended teaching quality evaluation scale with 35 items includes four dimensions Context, Input, Process and Product. The content validity and reliability of the blended teaching quality evaluation scale are both good, with a content validity index of 0.934 for the total scale and a content validity index of 0.750-1.00 for each item. The SEM shows that χ2/df = 6.89, RMSEA = 0.115, CFI = 0.882, NFI=0.865, RFI= 0.855, IFI = 0.882, TLI = 0.873. The Cronbach's α coefficient of the total scale is 0.991 and the Cronbach's α coefficient for each dimension is 0.944-0.984. CONCLUSION: The scale is based on the characteristics of blended learning and quality evaluation covers all aspects of teaching. It can accurately evaluate the quality of teaching, evaluate the problems in the teaching process based on the teaching quality score and propose reasonable teaching improvement suggestions based on the weak links in the teaching process.

11.
Fitoterapia ; 175: 105946, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38575087

RESUMO

Four compounds (1-4) featuring with an L-rhodinose and spiroketal, possess uncommon continuous hydroxy groups in the macrolide skeleton, and a dichloro-diketopiperazine (5) were isolated from a marine derived Micromonospora sp. FIMYZ51. The determination of the relative and absolute configurations of all isolates was achieved by extensive spectroscopic analyses, single-crystal X-ray diffraction analysis, and ECD calculations. According to structural characteristic and genomic sequences, a plausible biosynthetic pathway for compound 1-4 was proposed and a spirocyclase was inferred to be responsible for the formation of the rare spirocyclic moiety. Compounds 1-4 exhibited potent antifungal activities which is equal to itraconazole against Aspergillus niger. Compounds 1-5 exhibited different degree of inhibitory activities against opportunistic pathogenic bacteria of endocarditis (Micrococcus luteus) with MIC values ranging from 0.0625 µg/mL to 32 µg/mL. Compounds 2 and 3 showed moderate cytotoxicity against drug-resistant tumor cell lines (Namalwa and U266). The result not only provides active lead-compounds, but also reveal the potential of the spirocyclase gene resources from Micromonospora sp., which highlights the promising potential of the strain for biomedical applications.

12.
Chem Biodivers ; : e202400721, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639576

RESUMO

Two new nervogenic acid derivatives liparisnervosides Q (1) and R (5), as well as five known nervogenic acid derivatives (2-4, 6, 7) and four phenanthrenes (8-11) were isolated from the whole plant of Liparis nervosa (Thunb. ex A. Murray) Lindl.. Their structures were detremined using extensive spectroscopic techniques, including 1D, 2D NMR, and HR-ESI-MS, and acid hydrolysis. Furthermore, their antimicrobial and immunosuppressive activities were evaluated. Nervosine Ⅶ (3) exhibited antimicrobial activity against Staphylococcus aureus with an MIC of 62.5 µg/mL and inhibited the proliferation of human T cells with an IC50 value of 9.67 ± 0.96 µM. These findings contribute to our understanding of the potential pharmacological properties of these compounds.

13.
World J Psychiatry ; 14(3): 409-420, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38617988

RESUMO

BACKGROUND: Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis (MHD) that significantly affect their quality of life (QOL). High levels of social support can significantly improve the physical and mental well-being of patients undergoing MHD. Currently, there is limited research on how social support mediates the relationship between dysphoria, despondency, and overall QOL in patients undergoing MHD. It is imperative to investigate this mediating effect to mitigate dysphoria and despondency in patients undergoing MHD, ultimately enhancing their overall QOL. AIM: To investigate the mediating role of social support in relationships between dysphoria, despondency, and QOL among patients undergoing MHD. METHODS: Participants comprised 289 patients undergoing MHD, who were selected using a random sampling approach. The Social Support Rating Scale, Self-Rating Anxiety Scale, Self-Rating Depression Scale, and QOL Scale were administered. Correlation analysis was performed to examine the associations between social support, dysphoria, despondency, and QOL in patients undergoing MHD. To assess the mediating impact of social support on dysphoria, despondency, and QOL in patients undergoing MHD, a bootstrap method was applied. RESULTS: Significant correlations among social support, dysphoria, despondency, and quality in patients undergoing MHD were observed (all P < 0.01). Dysphoria and despondency negatively correlated with social support and QOL (P < 0.01). Dysphoria and despondency had negative predictive impacts on the QOL of patients undergoing MHD (P < 0.05). The direct effect of dysphoria on QOL was statistically significant (P < 0.05). Social support mediated the relationship between dysphoria and QOL, and this mediating effect was significant (P < 0.05). Similarly, the direct effect of despondency on QOL was significant (P < 0.05). Moreover, social support played a mediating role between despondency and QOL, with a significant mediating effect (P < 0.05). CONCLUSION: These findings suggest that social support plays a significant mediating role in the relationship between dysphoria, despondency, and QOL in patients undergoing MHD.

14.
World J Gastrointest Oncol ; 16(4): 1626-1646, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660634

RESUMO

BACKGROUND: Human-derived gastric cancer organoids (GCOs) are widely used in gastric cancer research; however, the culture success rate is generally low. AIM: To explore the potential influencing factors, and the literature on successful culture rates of GCOs was reviewed using meta-analysis. METHODS: PubMed, Web of Science, and EMBASE were searched for studies. Two trained researchers selected the studies and extracted data. STATA 17.0 software was used for meta-analysis of the incidence of each outcome event. The adjusted Methodological Index for Non-Randomized Studies scale was used to assess the quality of the included studies. Funnel plots and Egger's test were used to detect publication bias. Subgroup analyses were conducted for sex, tissue source, histological classification, and the pathological tumor-node-metastasis (pTNM) cancer staging system. RESULTS: Eight studies with a pooled success rate of 66.6% were included. GCOs derived from women and men had success rates of 67% and 46.7%, respectively. GCOs from surgery or biopsy/endoscopic submucosal dissection showed success rates of 70.9% and 53.7%, respectively. GCOs of poorly-differentiated, moderately-differentiated and signet-ring cell cancer showed success rates of 64.6%, 31%, and 32.7%, respectively. GCOs with pTNM stages I-II and III-IV showed success rates of 38.3% and 65.2%, respectively. Y-27632 and non-Y-27632 use showed success rates of 58.2% and 70%, respectively. GCOs generated with collagenase were more successful than those constructed with Liberase TH and TrypLE (72.1% vs 71%, respectively). EDTA digestion showed a 50% lower success rate than other methods (P = 0.04). CONCLUSION: GCO establishment rate is low and varies by sex, tissue source, histological type, and pTNM stage. Omitting Y-27632, and using Liberase TH, TrypLE, or collagenase yields greater success than EDTA.

15.
Artif Organs ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38660762

RESUMO

BACKGROUND: Vascular smooth muscle cells (VSMCs) are commonly used as seed cells in tissue-engineered vascular constructions. However, their variable phenotypes and difficult to control functions pose challenges. This study aimed to overcome these obstacles using a three-dimensional culture system. METHODS: Calf VSMCs were administered tumor necrosis factor-alpha (TNF-α) before culturing in two- and three-dimensional well plates and polyglycolic acid (PGA) scaffolds, respectively. The phenotypic markers of VSMCs were detected by immunofluorescence staining and western blotting, and the proliferation and migration abilities of VSMCs were detected by CCK-8, EDU, cell counting, scratch, and Transwell assays. RESULTS: TNF-α rapidly decreased the contractile phenotypic markers and elevated the synthetic phenotypic markers of VSMCs, as well as markedly increasing the proliferation and migration ability of VSMCs under two- and three-dimensional culture conditions. CONCLUSIONS: TNF-α can rapidly induce a phenotypic shift in VSMCs and change their viability on PGA scaffolds.

16.
Eur J Med Res ; 29(1): 249, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38650027

RESUMO

BACKGROUND: The contractile phenotype of vascular smooth muscle cells (VSMCs) results in good diastolic and contractile capacities, and its altered function is the main pathophysiological basis for diseases such as hypertension. VSMCs exist as a synthetic phenotype in vitro, making it challenging to maintain a contractile phenotype for research. It is widely recognized that the common medium in vitro is significantly less crowded than in the in vivo environment. Additionally, VSMCs have a heightened sense for detecting changes in medium crowding. However, it is unclear whether macromolecular crowding (MMC) helps maintain the VSMCs contractile phenotype. PURPOSE: This study aimed to explore the phenotypic, behavioral and gene expression changes of VSMCs after increasing the crowding degree by adding carrageenan (CR). METHODS: The degree of medium crowding was examined by a dynamic light scattering assay; VSMCs survival and activity were examined by calcein/PI cell activity and toxicity and CCK-8 assays; VSMCs phenotypes and migration were examined by WB and wound healing assays; and gene expression was examined by transcriptomic analysis and RT-qPCR. RESULTS: Notably, 225 µg/mL CR significantly increased the crowding degree of the medium and did not affect cell survival. Simultaneously, CR significantly promoted the contraction phenotypic marker expression in VSMCs, shortened cell length, decreased cell proliferation, and inhibited cell migration. CR significantly altered gene expression in VSMCs. Specifically, 856 genes were upregulated and 1207 genes were downregulated. These alterations primarily affect the cellular ion channel transport, microtubule movement, respiratory metabolism, amino acid transport, and extracellular matrix synthesis. The upregulated genes were primarily involved in the cytoskeleton and contraction processes of VSMCs, whereas the downregulated genes were mainly involved in extracellular matrix synthesis. CONCLUSIONS: The in vitro study showed that VSMCs can maintain the contractile phenotype by sensing changes in the crowding of the culture environment, which can be maintained by adding CR.

17.
JAMA Netw Open ; 7(4): e247145, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648060

RESUMO

Importance: Delayed meconium evacuation and delayed achievement of full enteral feeding among premature infants are associated with poor short- and long-term outcomes. Identifying a more effective and safer enema for meconium evacuation is imperative for improving neonatal care. Objective: To examine whether breast milk enemas can shorten the time to complete meconium evacuation and achievement of full enteral feeding for preterm infants. Design, Setting, and Participants: This randomized, open-label, parallel-group, single-center clinical trial was conducted from September 1, 2019, to September 30, 2022, among 286 preterm infants with a gestational age of 23 to 30 weeks in the neonatal ward of the Shengjing Hospital of China Medical University in Shenyang. Interventions: Preterm infants were randomly assigned to receive either breast milk enemas or normal saline enemas 48 hours after birth. Main Outcome and Measures: The primary outcomes were time to complete meconium evacuation and time to achieve full enteral feeding. Secondary outcomes were duration of hospitalization, weight at discharge, and duration of total parenteral nutrition. Intention-to-treat and per-protocol analyses were conducted. Results: In total, 286 preterm infants (mean [SD] gestational age, 198.8 [7.9] days; 166 boys [58.0%]) were eligible and included in this study. A total of 145 infants were randomized to the normal saline group, and 141 were randomized to the breast milk group. The time to achieve complete meconium evacuation was significantly shorter in the breast milk group than in the normal saline group (-2.2 days; 95% CI, -3.2 to -1.2 days). The time to achieve full enteral feeding was also significantly shorter in the breast milk group than in the normal saline group (-4.6 days; 95% CI, -8.0 to -1.2 days). The duration of total parenteral nutrition was significantly shorter in the breast milk group than in the normal saline group (-4.6 days; 95% CI, -8.6 to -1.0 days). There were no clinically notable differences in any other secondary or safety outcomes between the 2 groups. Conclusions and Relevance: In this randomized clinical trial testing the effects of breast milk enema on meconium evacuation, breast milk reduced the time to achieve complete meconium evacuation and achieve full enteral feeding for preterm infants with a gestational age of 23 to 30 weeks. Subgroup analyses highlight the need for tailored interventions based on gestational age considerations. Trial Registration: isrctn.org Identifier: ISRCTN17847514.

18.
Carbohydr Polym ; 333: 121929, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494211

RESUMO

Polymerized guluronates (polyG)-specific alginate lyase with lower polymerized mannuronates (polyM)-degrading activity, superior stability, and clear action mode is a powerful biotechnology tool for the preparation of AOSs rich in M blocks. In this study, we expressed and characterized a polyG-specific alginate lyase OUC-FaAly7 from Formosa agariphila KMM3901. OUC-FaAly7 belonging to polysaccharide lyase (PL) family 7 had highest activity (2743.7 ± 20.3 U/µmol) at 45 °C and pH 6.0. Surprisingly, its specific activity against polyG reached 8560.2 ± 76.7 U/µmol, whereas its polyM-degrading activity was nearly 0 within 10 min reaction. Suggesting that OUC-FaAly7 was a strict polyG-specific alginate lyase. Importantly, OUC-FaAly7 showed a wide range of temperature adaptations and remarkable temperature and pH stability. Its relative activity between 20 °C and 45 °C reached >90 % of the maximum activity. The minimum identifiable substrate of OUC-FaAly7 was guluronate tetrasaccharide (G4). Action process and mode showed that it was a novel alginate lyase digesting guluronate hexaose (G6), guluronate heptaose (G7), and polymerized guluronates, with the preferential generation of unsaturated guluronate pentasaccharide (UG5), although which could be further degraded into unsaturated guluronate disaccharide (UG3) and trisaccharide (UG2). This study contributes to illustrating the catalytic properties, substrate recognition, and action mode of novel polyG-specific alginate lyases.


Assuntos
Dissacarídeos , Oligossacarídeos , Especificidade por Substrato , Oligossacarídeos/metabolismo , Dissacarídeos/metabolismo , Polissacarídeo-Liases/metabolismo , Alginatos/metabolismo , Concentração de Íons de Hidrogênio , Proteínas de Bactérias/química
19.
J Vis Exp ; (205)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38497658

RESUMO

The investigation of interactions between different molecules is a crucial aspect of understanding disease pathogenesis and screening for drug targets. Umbelliferone, an active ingredient in Tibetan medicine Vicatia thibetica, exhibits an immunomodulatory effect with an unknown mechanism. The CD40 protein is a key target in the immune response. Therefore, this study employs the principle of differential scanning fluorescence technology to analyze the interactions between CD40 protein and umbelliferone using fluorescent enzyme markers. Initially, the stability of the protein fluorescent orange dye was experimentally verified, and the optimal dilution ratio of 1:500 was determined. Subsequently, it was observed that the temperature melting (Tm) value of CD40 protein tended to decrease with an increase in concentration. Interestingly, the interaction between CD40 protein and umbelliferone was found to enhance the thermal stability of CD40 protein. This study represents the first attempt to detect the binding potential of small molecule compounds and proteins using fluorescence microplates and fluorescent dyes. The technique is characterized by high sensitivity and accuracy, promising advancements in the fields of protein stability, protein structure, and protein-ligand interactions, thus facilitating further research and exploration.


Assuntos
Sistemas de Liberação de Medicamentos , Corantes Fluorescentes , Fluorescência , Imunomodulação , Cintilografia
20.
Anesth Analg ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38507523

RESUMO

BACKGROUND: Sevoflurane induces neuronal dysfunction and cognitive impairment. However, the underlying mechanism remains largely to be determined. Tau, cyclophilin D, and dendritic spine contribute to cognitive function. But whether changes in dendritic spines are involved in the effects of sevoflurane and the potential association with tau and cyclophilin D is not clear. METHODS: We harvested hippocampal neurons from wild-type mice, tau knockout mice, and cyclophilin D knockout mice. We treated these neurons with sevoflurane at day in vitro 7 and measured the diameter of dendritic spine head and the number of dendritic spines. Moreover, we determined the effects of sevoflurane on the expression of excitatory amino acid transporter 3 (EAAT3), extracellular glutamate levels, and miniature excitatory postsynaptic currents (mEPSCs). Finally, we used lithium, cyclosporine A, and overexpression of EAAT3 in the interaction studies. RESULTS: Sevoflurane-induced tau phosphgorylation increased the diameter of dendritic spine head and decreased the number of dendritic spines in neurons harvested from wild-type and cyclophilin D knockout mice, but not tau knockout mice. Sevoflurane decreased the expression of EAAT3, increased extracellular glutamate levels, and decreased the frequency of mEPSCs in the neurons. Overexpression of EAAT3 mitigated the effects of sevoflurane on dendritic spines. Lithium, but not cyclosporine A, attenuated the effects of sevoflurane on dendritic spines. Lithium also inhibited the effects of sevoflurane on EAAT3 expression and mEPSCs. CONCLUSIONS: These data suggest that sevoflurane induces a tau phosphorylation-dependent demtrimental effect on dendritic spine via decreasing EAAT3 expression and increasing extracellular glutamate levels, leading to neuronal dysfunction.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...