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1.
Front Med (Lausanne) ; 11: 1409534, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841589

RESUMO

Purpose: Osteoporosis represents a profound challenge to public health, underscoring the critical need to dissect its complex etiology and identify viable targets for intervention. Within this context, the gut microbiota has emerged as a focal point of research due to its profound influence on bone metabolism. Despite this growing interest, the literature has yet to see a bibliometric study addressing the gut microbiota's contribution to both the development and management of osteoporosis. This study aims to fill this gap through an exhaustive bibliometric analysis. Our objective is to uncover current research hotspots, delineate key themes, and identify future research trends. In doing so, we hope to provide direction for future studies and the development of innovative treatment methods. Methods: Relevant publications in this field were retrieved from the Web of Science Core Collection database. We used VOSviewer, CiteSpace, an online analysis platform and the R package "Bibliometrix" for bibliometric analysis. Results: A total of 529 publications (including 351 articles and 178 reviews) from 61 countries, 881 institutions, were included in this study. China leads in publication volume and boast the highest cumulative citation. Shanghai Jiao Tong University and Southern Medical University are the leading research institutions in this field. Nutrients contributed the largest number of articles, and J Bone Miner Res is the most co-cited journal. Of the 3,166 scholars who participated in the study, Ohlsson C had the largest number of articles. Li YJ is the most co-cited author. "Probiotics" and "inflammation" are the keywords in the research. Conclusion: This is the first bibliometric analysis of gut microbiota in osteoporosis. We explored current research status in recent years and identified frontiers and hot spots in this research field. We investigate the impact of gut microbiome dysregulation and its associated inflammation on OP progression, a topic that has garnered international research interest in recent years. Additionally, our study delves into the potential of fecal microbiota transplantation or specific dietary interventions as promising avenues for future research, which can provide reference for the researchers who focus on this research filed.

2.
Adv Mater ; : e2402257, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831681

RESUMO

Ultralong carbon nanotubes (CNTs) are considered as promising candidates for many cutting-edge applications. However, restricted by the extremely low yields of ultralong CNTs, their practical applications can hardly be realized. Therefore, new methodologies shall be developed to boost the growth efficiency of ultralong CNTs and alleviate their areal density decay at the macroscale level. Herein, a facile, universal, and controllable method for the in situ synthesis of floating bimetallic catalysts (FBCs) is proposed to grow ultralong CNT arrays with high yields and uniformity. Ferrocene and metal acetylacetonates serve as catalyst precursors, affording the successful synthesis of a series of FBCs with controllable compositions. Among these FBCs, the optimized FeCu catalyst increases the areal density of ultralong CNT arrays to a record-breaking value of ≈8100 CNTs mm-1 and exhibits a lifetime 3.40 times longer than that of Fe, thus achieving both high yields and uniformity. A 30-centimeters-long and high-density ultralong CNT array is also successfully grown with the assistance of FeCu catalysts. As evidenced by this kinetic model and molecular dynamics simulations, the introduction of Cu into Fe can simultaneously improve the catalyst fluidity and decrease carbon solubility, and an optimal catalytic performance will be achieved by balancing this tradeoff.

3.
Am J Hypertens ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850192

RESUMO

BACKGROUND: Salt-sensitive hypertension is often more prone to induce damage to target organs such as the heart and kidneys. Abundant recent studies have demonstrated a close association between ferroptosis and cardiovascular diseases.Therefore, we hypothesize that ferroptosis may be closely associated with organ damage in salt-sensitive hypertension. This study aimed to investigate whether ferroptosis is involved in the occurrence and development of myocardial fibrosis and renal fibrosis in salt-sensitive hypertensive rats. METHODS: Ten 7-week-old male Dahl salt-sensitive (Dahl-SS) rats were adaptively fed for 1 week, then randomly divided into two groups and fed either a normal diet (0.3% NaCl, NDS group) or a high-salt diet (8% NaCl, HDS group) for 8 weeks. Blood pressure of the rats was observed, and analysis of the hearts and kidneys of Dahl-SS rats was conducted via HE-staining, Masson-staining, Prussian-blue-staining, TEM, tissue iron content detection, MDA content detection, immunofluorescence, and Western blot. RESULTS: Compared to the NDS group, rats in the HDS group increases in systolic blood pressure(SBP) and diastolic blood pressure(DBP)(P<0.05);collagen fiber accumulation was observed in the heart and kidney tissues (P<0.01), accompanied by alterations in mitochondrial ultrastructure,reduced mitochondrial volume, and increased density of the mitochondrial double membrane. Additionally,there were significant increases in both iron content and MDA levels(P<0.05). Immunofluorescence and Western blot results both indicated significant downregulation (P<0.05) of xCT and GPX4 proteins associated with ferroptosis in the HDS group. CONCLUSION: Ferroptosis is involved in the damage and fibrosis of the heart and kidney tissues in salt-sensitive hypertensive rats.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38857204

RESUMO

ABSTRACT: Diabetic retinopathy (DR) is a secondary complication of diabetes that can lead to visual impairment and blindness. The retinal pigment epithelium (RPE) is a monolayer of pigment cells that forms the blood-retinal barrier (BRB) via tight junction (TJ) proteins and plays a crucial role in the physiological function of the retina. Hyperglycemia induces RPE death and BRB breakdown, which accelerates the process of DR. Curcumin, an active extract of Curcuma longa, has anti-inflammatory, antioxidant, antiapoptotic, and neuroprotective properties. However, the effect of Curcumin on the BRB under high glucose conditions remains unknown. This study aimed to investigate the protective effects of Curcumin on RPE physiology in vitro and in vivo. Curcumin significantly alleviated cell viability inhibition under high glucose conditions. Moreover, high glucose reduced extracellular signal-regulated kinase and Akt pathways activation to diminish RPE cell growth but reversed by Curcumin treatment. Curcumin protected not only TJ integrity but also retinoid regeneration through TJ proteins and isomerase modulation in diabetic retina. Furthermore, Curcumin decreased the expression of angiogenic factor to inhibit retinal neovascularization. Finally, Curcumin treatment markedly reduced apoptosis during hyperglycemia. In conclusion, Curcumin can alleviate the progression of DR by promoting RPE survival, TJ integrity, retinoid isomerase activity, RPE senescence inhibition, and neovascularization. Therefore, Curcumin exhibits high potential for use as a therapeutic agent for early DR.

5.
JMIR Public Health Surveill ; 10: e56643, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861303

RESUMO

BACKGROUND: Male-to-male sexual transmission continues to account for the greatest proportion of new HIV diagnoses in the United States. However, calculating population-specific surveillance metrics for HIV and other sexually transmitted infections requires regularly updated estimates of the number and proportion of men who have sex with men (MSM) in the United States, which are not collected by census surveys. OBJECTIVE: The purpose of this analysis was to estimate the number and percentage of MSM in the United States from population-based surveys. METHODS: We used data from 5 population-based surveys to calculate weighted estimates of the proportion of MSM in the United States and pooled these estimates using meta-analytic procedures. We estimated the proportion of MSM using sexual behavior-based questions (encompassing anal or oral sex) for 3 recall periods-past 12 months, past 5 years, and lifetime. In addition, we estimated the proportion of MSM using self-reported identity and attraction survey responses. The total number of MSM and non-MSM in the United States were calculated from estimates of the percentage of MSM who reported sex with another man in the past 12 months. RESULTS: The percentage of MSM varied by recall period: 3.3% (95% CI 1.7%-4.9%) indicated sex with another male in the past 12 months, 4.7% (95% CI 0.0%-33.8%) in the past 5 years, and 6.2% (95% CI 2.9%-9.5%) in their lifetime. There were comparable percentages of men who identified as gay or bisexual (3.4%, 95% CI 2.2%-4.6%) or who indicated that they are attracted to other men (4.9%, 95% CI 3.1%-6.7%) based on pooled estimates. Our estimate of the total number of MSM in the United States is 4,230,000 (95% CI 2,179,000-6,281,000) based on the history of recent sexual behavior (sex with another man in the past 12 months). CONCLUSIONS: We calculated the pooled percentage and number of MSM in the United States from a meta-analysis of population-based surveys collected from 2017 to 2021. These estimates update and expand upon those derived from the Centers for Disease Control and Prevention in 2012 by including estimates of the percentage of MSM based on sexual identity and sexual attraction. The percentage and number of MSM in the United States is an important indicator for calculating population-specific disease rates and eligibility for preventive interventions such as pre-exposure prophylaxis.


Assuntos
Homossexualidade Masculina , Humanos , Masculino , Estados Unidos/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Homossexualidade Masculina/psicologia , Inquéritos e Questionários , Adulto , Densidade Demográfica , Comportamento Sexual/estatística & dados numéricos
6.
Chem Biodivers ; : e202401220, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869421

RESUMO

Anoectochilus roxburghii is a well-known and valuable traditional Chinese herb due to various medicinal and functional benefits. In-depth investigation is necessary to discover active ingredients and expand its application. In this study, four new compounds (1-4) along with ten known compounds (5-14) were isolated from the ethanol extract ofA.roxburghii. Their structures were elucidated by spectroscopic data interpretation. The isolates were screened for their inhibitory activities on the production of NO in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Among them, compounds 5, 6, 9, 10, 12, 13 and 14exhibited significant anti-inflammatory activity through inhibiting the release of NO.

7.
Res Sq ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38883748

RESUMO

Proteomic profiling of Alzheimer's disease (AD) brains has identified numerous understudied proteins, including midkine (MDK), that are highly upregulated and correlated with Aß since the early disease stage, but their roles in disease progression are not fully understood. Here we present that MDK attenuates Aß assembly and influences amyloid formation in the 5xFAD amyloidosis mouse model. MDK protein mitigates fibril formation of both Aß40 and Aß42 peptides in Thioflavin T fluorescence assay, circular dichroism, negative stain electron microscopy, and NMR analysis. Knockout of Mdk gene in 5xFAD increases amyloid formation and microglial activation. Further comprehensive mass spectrometry-based profiling of whole proteome and aggregated proteome in these mouse models indicates significant accumulation of Aß and Aß-correlated proteins, along with microglial components. Thus, our structural and mouse model studies reveal a protective role of MDK in counteracting amyloid pathology in Alzheimer's disease.

8.
Obes Rev ; : e13760, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697953

RESUMO

A systematic review and meta-analysis was conducted to evaluate the relative effectiveness of different dietary macronutrient patterns on changes in resting energy expenditure (REE) in relation to weight loss, categorized as minimal (<5%) and moderate to high (>5%). Changes in REE were assessed using a DerSimonian and Laird random-effects meta-analysis. A diet lower in carbohydrates (CHO) or higher in fat and protein was associated with smaller reductions in REE, with these trends being more pronounced among participants who experienced moderate to high weight loss. Adjusted meta-regression analysis indicated that, within the participants who experienced moderate to high weight loss, each 1% increase in CHO intake was associated with a reduction of 2.30 kcal/day in REE (95% CI: -4.11 to -0.47, p = 0.013). In contrast, a 1% increase in protein and fat intake was correlated with an increase in REE by 3.00 (95% confidence interval [CI] [1.02, 5.07], p = 0.003) and 0.5 (95% CI [-2.43, 3.41], p = 0.740) kcal/day, respectively. No significant associations were found among participants who experienced minimal weight loss. These findings indicate that, under a caloric deficit, the impact of dietary macronutrient composition on REE may vary depending on the degree of weight loss and individual metabolic responses.

9.
Chronic Illn ; : 17423953241253874, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38751071

RESUMO

OBJECTIVES: To examine the impact of social and emotional support on serious psychological distress (SPD) in individuals with type 2 diabetes (T2DM) and functional disabilities after controlling for socio-demographic factors and health status. Findings provide information for healthcare providers to enhance patients' psychological well-being. METHODS: Data from 529 adults were obtained from the 2021 National Health Interview Survey, including those who had T2DM and also reported significant difficulty or inability to perform an activity in any of the following domains: seeing, hearing, walking or climbing stairs, communicating, remembering or concentrating, or practicing self-care. Descriptive analysis and a hierarchical regression model of SPD were used. RESULTS: The mean age of participants was 67.88 years old, and the mean duration of diabetes diagnosis was 16.88 years. Notably, 12.5% of individuals reported SPD. A decreased likelihood of reporting SPD occurrence was associated with older age (odds ratio (OR) = 0.95), a longer duration of T2DM diagnosis (OR = 0.97), having at least a high school education (OR = 0.54), and receiving social and emotional support. DISCUSSION: Social and emotional support likely mitigates psychological distress, suggesting that social and emotional support resources should be enhanced, especially among individuals who are younger and those more recently diagnosed with T2DM.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38768983

RESUMO

BACKGROUND: Early retirement is highly prevalent in Taiwan. This study assesses the association between early retirement and all-cause and cause-specific mortality risks while exploring the modifying effect of sociodemographic factors. METHODS: Using Taiwan's National Health Insurance Research Database between 2009 and 2019, 1 762 621 early retirees aged 45-64 and an equal number of employed comparators were included. The date and cause of death were identified using the National Death Registry. Cox regression models were used to estimate HRs of early retirement for all-cause mortality and cause-specific mortality. To explore modifying effects, we conducted subgroup analyses based on age groups, sexes, occupation types and general health status (Charlson Comorbid Index score). RESULTS: The analysis revealed that early retirees, compared with their concurrently employed counterparts, had a higher mortality risk (adjusted HR (aHR) 1.69, 95% CI (1.67 to 1.71)). Specifically, younger individuals (aged 45-54) (aHR 2.74 (95% CI 2.68 to 2.80)), males (aHR 1.78 (95% CI 1.76 to 1.81)), those in farming or fishing occupations (aHR 2.13 (95% CI 2.06 to 2.21)) or the private sector (aHR 1.92 (95% CI 1.89 to 1.96)), and those with the poorest health conditions (aHR 1.79 (95% CI 1.76 to 1.83)) had higher mortality risks of early retirement. Regarding specific causes of death, the top three highest risks were associated with gastrointestinal disorders, followed by suicide and neurological disorders. CONCLUSIONS: This study underscores the substantial mortality risk increase linked to early retirement, emphasising the importance of policy considerations, particularly regarding vulnerable populations and specific causes of death potentially linked to unhealthy lifestyles.

11.
Stem Cell Res Ther ; 15(1): 143, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764049

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a debilitating illness in humans that causes permanent loss of movement or sensation. To treat SCI, exosomes, with their unique benefits, can circumvent limitations through direct stem cell transplantation. Therefore, we utilized Gelfoam encapsulated with exosomes derived from human umbilical cord mesenchymal stem cells (HucMSC-EX) in a rat SCI model. METHODS: SCI model was established through hemisection surgery in T9 spinal cord of female Sprague-Dawley rats. Exosome-loaded Gelfoam was implanted into the lesion site. An in vivo uptake assay using labeled exosomes was conducted on day 3 post-implantation. Locomotor functions and gait analyses were assessed using Basso-Beattie-Bresnahan (BBB) locomotor rating scale and DigiGait Imaging System from weeks 1 to 8. Nociceptive responses were evaluated through von Frey filament and noxious radiant heat tests. The therapeutic effects and potential mechanisms were analyzed using Western blotting and immunofluorescence staining at week 8 post-SCI. RESULTS: For the in vivo exosome uptake assay, we observed the uptake of labeled exosomes by NeuN+, Iba1+, GFAP+, and OLIG2+ cells around the injured area. Exosome treatment consistently increased the BBB score from 1 to 8 weeks compared with the Gelfoam-saline and SCI control groups. Additionally, exosome treatment significantly improved gait abnormalities including right-to-left hind paw contact area ratio, stance/stride, stride length, stride frequency, and swing duration, validating motor function recovery. Immunostaining and Western blotting revealed high expression of NF200, MBP, GAP43, synaptophysin, and PSD95 in exosome treatment group, indicating the promotion of nerve regeneration, remyelination, and synapse formation. Interestingly, exosome treatment reduced SCI-induced upregulation of GFAP and CSPG. Furthermore, levels of Bax, p75NTR, Iba1, and iNOS were reduced around the injured area, suggesting anti-inflammatory and anti-apoptotic effects. Moreover, exosome treatment alleviated SCI-induced pain behaviors and reduced pain-associated proteins (BDNF, TRPV1, and Cav3.2). Exosomal miRNA analysis revealed several promising therapeutic miRNAs. The cell culture study also confirmed the neurotrophic effect of HucMSCs-EX. CONCLUSION: Implantation of HucMSCs-EX-encapsulated Gelfoam improves SCI-induced motor dysfunction and neuropathic pain, possibly through its capabilities in nerve regeneration, remyelination, anti-inflammation, and anti-apoptosis. Overall, exosomes could serve as a promising therapeutic alternative for SCI treatment.


Assuntos
Modelos Animais de Doenças , Exossomos , Células-Tronco Mesenquimais , Neuralgia , Ratos Sprague-Dawley , Traumatismos da Medula Espinal , Animais , Traumatismos da Medula Espinal/terapia , Exossomos/metabolismo , Neuralgia/terapia , Neuralgia/metabolismo , Ratos , Feminino , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Locomoção , Esponja de Gelatina Absorvível , Cordão Umbilical/citologia
12.
BMC Womens Health ; 24(1): 308, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783282

RESUMO

BACKGROUND: Cervical mullerian adenosarcoma is a rare uterine sarcoma, especially in young women. Its pathological features are low-grade malignant tumors with bidirectional differentiation, and the degree of malignancy is similar to that of low-grade endometrial stromal sarcoma. This paper reports the case of a young asexual patient who has been closely followed up after tumor resection and has not had any recurrences. CASE PRESENTATION: A 20-year-old, young asexual woman was diagnosed with cervical mullerian adenosarcoma with sarcomatous overgrowth (MASO). Cervical tumor resection was performed after admission, and the resection margin was negative. After the operation, she refused to undergo secondary surgery due to fertility requirements and did not receive adjuvant treatment. The patient was closely followed up after the operation and has not yet relapsed. CONCLUSION: A young woman with cervical MASO did not receive adjuvant treatment after cervical tumor resection. For women with fertility requirements, close follow-ups should be conducted after the operation to guard against tumor recurrence and radical tumor resection should be performed as early as possible after the patient no longer requires their fertility.


Assuntos
Adenossarcoma , Neoplasias do Colo do Útero , Neoplasias Uterinas , Humanos , Feminino , Adenossarcoma/cirurgia , Adenossarcoma/patologia , Adenossarcoma/diagnóstico , Adulto Jovem , Neoplasias do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias Uterinas/cirurgia , Neoplasias Uterinas/patologia , Neoplasias Uterinas/complicações , Neoplasias Uterinas/diagnóstico , Comportamento Sexual
13.
One Health ; 18: 100757, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38803321

RESUMO

Helicobacter species are potential zoonotic pathogens classified as either enterohepatic or gastric. Helicobacter infection can be transmitted through wastewater from households and livestock and through water from irrigation and streams. In this study, the distribution and source of Helicobacter species in the Donggang and Yenshui rivers, two natural water bodies with different characteristics, were analyzed. A total of 44 water samples were collected over the four seasons. The samples were subjected to Helicobacter 16 s rRNA gene PCR, followed by sequencing and comparison for identification and analysis. The detection rate of Helicobacter species in both rivers was 79.55%, with H. kayseriensis (10/35, 28.57%) being the most common species. Analysis of the environment around the sampling sites showed a high detection rate in the livestock-rich area, and the results of BLAST for species identification and comparison indicated feces as the contamination source. The area around the Donggang River was developed for animal husbandry, led to a high detection rate of Helicobacter species. Many Helicobacter species were identified to have a risk of zoonotic transmission, especially if the stream is used as a source of drinking, agricultural, or even aquacultural water. The high presence of Helicobacter species in natural water bodies suggests that wastewater treatment is an effective strategy to control pathogen spread. Therefore, investigation and monitoring of pathogens in wastewater are highly important. However, methods for the isolation and culture of Helicobacter species in natural waters have yet to be developed. Hence, future research should focus on developing such methods.

14.
Arch Toxicol ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753188

RESUMO

Long interspersed nuclear element-1 (LINE-1) methylation serves as an indicator of global DNA methylation. This study explored the correlation between LINE-1 methylation and chronic kidney disease (CKD). We also evaluated whether LINE-1 methylation could modify the association between CKD and metal exposure. A total of 213 patients with clinically defined CKD, without hemodialysis and 416 age and sex matched controls were recruited. Levels of LINE-1 methylation, total urinary arsenic, blood lead, blood cadmium, and plasma selenium were assessed. The results reveal a positive association between LINE-1 methylation and CKD, with an odds ratio (OR) of 5.30 (95% confidence interval: 2.81 to 9.99). Total urinary arsenic and blood cadmium concentrations were positively related with LINE-1 methylation. This study was the first to observe that low plasma selenium, high blood cadmium, and high blood lead levels significantly and additively interact with increased LINE-1 methylation to increase the OR of CKD. Additionally, high LINE-1 methylation interacted multiplicatively with low plasma selenium to increase the OR of CKD (p < 0.001). This study highlighted the significant association between LINE-1 hypermethylation and CKD. Furthermore, the results demonstrate that LINE-1 methylation can interact with high blood cadmium or low plasma selenium to affect CKD risk.

15.
Dermatol Surg ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820425

RESUMO

BACKGROUND: Striae distensae (SD) are cutaneous lesions that are caused by hormones or mechanical stress leading to rapid expansion of skin. Therefore, SD are now a cosmetic concern. However, improving SD is notoriously difficult. Among different treatments, energy-based devices (EBDs) are much more effective and controllable. OBJECTIVE: The aim of this review was to determine the most effective type of EBD for improving the appearance of striae. MATERIALS AND METHODS: The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The population comprised patients suffering from striae. Different types of EBDs used to improve striae were compared. The primary outcome of the reduction in the width of striae was evaluated. A random-effects model was performed. The means and standard deviations were extracted. RESULTS: Eighteen randomized controlled trials were included. The network meta-analysis revealed that after a comparison among the 4 types of EBDs, no significant differences were observed in the reduction of striae width. CONCLUSION: Radiofrequency, ablative lasers, nonablative lasers, and intense pulsed light are all effective treatments for reducing the striae width. None of them was superior to the others. However, radiofrequency and ablative lasers may have the highest chance of improving the appearance of striae.

16.
Nat Commun ; 15(1): 3850, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719864

RESUMO

The K+ uptake system KtrAB is essential for bacterial survival in low K+ environments. The activity of KtrAB is regulated by nucleotides and Na+. Previous studies proposed a putative gating mechanism of KtrB regulated by KtrA upon binding to ATP or ADP. However, how Na+ activates KtrAB and the Na+ binding site remain unknown. Here we present the cryo-EM structures of ATP- and ADP-bound KtrAB from Bacillus subtilis (BsKtrAB) both solved at 2.8 Å. A cryo-EM density at the intra-dimer interface of ATP-KtrA was identified as Na+, as supported by X-ray crystallography and ICP-MS. Thermostability assays and functional studies demonstrated that Na+ binding stabilizes the ATP-bound BsKtrAB complex and enhances its K+ flux activity. Comparing ATP- and ADP-BsKtrAB structures suggests that BsKtrB Arg417 and Phe91 serve as a channel gate. The synergism of ATP and Na+ in activating BsKtrAB is likely applicable to Na+-activated K+ channels in central nervous system.


Assuntos
Bacillus subtilis , Proteínas de Bactérias , Proteínas de Transporte de Cátions , Potássio , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Sítios de Ligação , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/química , Microscopia Crioeletrônica , Cristalografia por Raios X , Modelos Moleculares , Potássio/metabolismo , Ligação Proteica , Sódio/metabolismo
17.
Int J Biol Macromol ; 270(Pt 1): 132066, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705323

RESUMO

A comprehensive multiscale analysis was conducted to explore the effects of different ratios of these materials on its properties. The results show that KC played a crucial role in controlling solution viscosity and gel and sol temperatures. The dissolution time at high water temperatures primarily decreased with an increase in SA content. Higher KC and CS content increased tensile strength (TS) and elongation at break (ε), while also exhibiting better thermal stability. Water vapor transmission (WVT) and permeability (PV) initially decreased, then increased with the increase of SA and CS contents. Finally, an SA:KC:CS ratio of 1:3:2 showed optimal comprehensive properties, with a dissolution time of about 60.0 ± 3.8 s, TS of 23.80 ± 0.29 MPa, ε of 18.61 ± 0.34 %, WVT of 21.74 ± 0.62 g/m2·24h, and PV of 5.39 ± 0.17 meq/kg. Meanwhile, the SA:KC:CS edible food packaging only introduced minimal effects on food after dissolution, and the total bacterial count met regulatory standards.


Assuntos
Filmes Comestíveis , Embalagem de Alimentos , Permeabilidade , Água , Embalagem de Alimentos/métodos , Água/química , Polissacarídeos/química , Solubilidade , Temperatura Alta , Viscosidade , Resistência à Tração , Vapor , Fenômenos Mecânicos , Fast Foods/análise
18.
Org Lett ; 26(22): 4672-4677, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38787765

RESUMO

Picrachinentins A-F (1-6, respectively), six novel cyclopeptide alkaloid-type burpitides (CPABs), were isolated and fully elucidated from the EtOH extract of the stems and leaves of Picrasma chinensis. Structurally, compounds 1-6 have a 14-membered paracyclophane ring system that was closed through an ether bond between the ß-hydroxy amino acid and tyrosine and modified with a 4,5-methylenedioxybenzoyloxy (MDBz, 3 and 5) or hexanoyl (Hexa, 1, 2, 4, and 6) group at the N-terminus. Interestingly, this is the first report on the isolation and characterization of CPABs from plants of the Simaroubaceae family. In addition, all compounds showed a neuroprotective effect against H2O2-damaged SH-SY5Y cells. Compound 1 was further investigated for its neuroprotective activities using a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease animal model, and it dramatically improved MPTP-impaired motor behavioral performance. Biochemical analysis revealed compound 1 restored the tyrosine hydroxylase expression in the striatum of the MPTP-damaged mouse brain, which demonstrates its protective effect on dopaminergic neurons.


Assuntos
Alcaloides , Fármacos Neuroprotetores , Peptídeos Cíclicos , Picrasma , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Animais , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/isolamento & purificação , Camundongos , Picrasma/química , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Estrutura Molecular , Humanos , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/antagonistas & inibidores , Folhas de Planta/química , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia
19.
Pathol Res Pract ; 256: 155287, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38579576

RESUMO

The lack of expression of terminal deoxynucleotidyl transferase (TdT) is frequently associated with KMT2A-rearranged subtype of pediatric acute lymphoblastic leukemia (ALL). However, this association has not been investigated extensively in the Asian population. A retrospective analysis of TdT expression in pediatric B-cell ALL (B-ALL) was performed in patients treated using the Taiwan Pediatric Oncology Group (TPOG) ALL 2002 and 2013 protocols. Among the 331 patients with B-ALL, 12 patients showed TdT negativity at initial diagnosis. Among these, eight patients showed KMT2A rearrangement (66.7%). Other patients showing negative TdT expression had ETV6::RUNX1, MEF2D-rearranged, and other B-ALL subtypes. However, in the context of KMT2A-rearranged B-ALL (n = 20), only eight patients showed TdT negativity. The 5-year event-free survival and overall survival of patients with and without TdT expression were 83.8% versus 46.8% (P <0.001) and 86.3% versus 55.4% (P = 0.004), respectively. Moreover, several aberrant markers, such as CD2, CD56, CD7, and CD117, were rarely expressed in the B-ALL samples, and if expressed, they were enriched in specific genetic subtypes. The results of this study indicate that immunophenotypic features are correlated with specific genetic subtypes of childhood B-ALL.


Assuntos
DNA Nucleotidilexotransferase , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , DNA Nucleotidilexotransferase/metabolismo , Estudos Retrospectivos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico
20.
World J Pediatr ; 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613734

RESUMO

BACKGROUND: Vasovagal syncope (VVS) is the most common type of orthostatic intolerance in children. We investigated whether platelet-related factors related to treatment efficacy in children suffering from VVS treated with metoprolol. METHODS: Metoprolol-treated VVS patients were recruited. The median duration of therapy was three months. Patients were followed and divided into two groups, treament-effective group and treatment-ineffective group. Logistic and least absolute shrinkage selection operator regressions were used to examine treatment outcome variables. Receiver-operating characteristic (ROC) curves, precision-recall (PR) curves, calibration plots, and decision curve analyses were used to evaluate the nomogram model. RESULTS: Among the 72 patients who complete the follow-up, treatment-effective group and treatment-ineffective group included 42 (58.3%) and 30 (41.7%) cases, respectively. The patients in the treatment-effective group exhibited higher mean platelet volume (MPV) [(11.0 ± 1.0) fl vs. (9.8 ± 1.0) fl, P < 0.01] and platelet distribution width [12.7% (12.3%, 14.3%) vs. 11.3% (10.2%, 12.2%), P < 0.01] than those in the treatment-ineffective group. The sex ratio was significantly different (P = 0.046). A fit model comprising age [odds ratio (OR) = 0.766, 95% confidence interval (CI) = 0.594-0.987] and MPV (OR = 5.613, 95% CI = 2.297-13.711) might predict therapeutic efficacy. The area under the curve of the ROC and PR curves was computed to be 0.85 and 0.9, respectively. The P value of the Hosmer-Lemeshow test was 0.27. The decision curve analysis confirmed that managing children with VVS based on the predictive model led to a net advantage ranging from 0.01 to 0.58. The nomogram is convenient for clinical applications. CONCLUSION: A novel nomogram based on age and MPV can predict the therapeutic benefits of metoprolol in children with VVS.

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