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1.
Int J Biol Macromol ; 265(Pt 1): 130703, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458279

RESUMO

Marine fungal exopolysaccharides play a crucial role in immunoregulation. In this investigation, a novel polysaccharide was extracted from the culture medium of the marine fungus Aspergillus medius SCAU-236. Compositional analysis revealed a structure composed of glucose units with (1,4)-α-D-Glcp, (1,3,4)-ß-D-Glcp, and (1,4,6)-α-D-Glcp, along with side chains of 1-α-D-Glcp linked to carbon 6 of (1,4,6)-α-D-Glcp and carbon 3 of (1,3,4)-ß-D-Glcp. Functional evaluations on RAW264.7 macrophage cells demonstrated Aspergillus medius polysaccharide (ASMP)'s effects on cell proliferation, nitric oxide levels, and the secretion of TNF-α, IL-6, and IL-1ß cytokines. Additionally, metabolomics indicated ASMP's potential to modulate macrophage immune function by impacting key regulatory molecules, including COX-2, iNOS, Nrf2, SLC7A11, GPX4, and ACSL4. The Nrf2/SLC7A11/GPX4 axis and ACSL4 were suggested to be involved in ASMP-induced ferroptosis, leading to increased reactive oxygen species (ROS) levels and lipid peroxidation. These findings propose a unique mechanism by which ASMP exerts immunomodulatory effects through ferroptosis induction, contributing to the understanding of marine-derived compounds in immunomodulation research.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Ferroptose , Fator 2 Relacionado a NF-E2 , Tionucleotídeos , Animais , Camundongos , Aspergillus/química , Polissacarídeos/química , Células RAW 264.7 , Imunidade , Imunomodulação , Carbono
2.
Front Public Health ; 12: 1152555, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327575

RESUMO

Introduction: Spatially segregated, socio-economically deprived communities in Europe are at risk of being neglected in terms of health care. In Hungary, poor monitoring systems and poor knowledge on the health status of people in these segregated areas prevent the development of well-informed effective interventions for these vulnerable communities. Aims: We used data available from National Health Insurance Fund Management to better describe health care performance in segregated communities and to develop more robust monitoring systems. Methods: A cross-sectional study using 2020 health care data was conducted on each general medical practice (GMP) in Hungary providing care to both segregated and nonsegregated (complementary) adult patients. Segregated areas were mapped and ascertained by a governmental decree that defines them as within settlement clusters of adults with low level of education and income. Age, sex, and eligibility for exemption certificate standardized indicators for health care delivery, reimbursement, and premature mortality were computed for segregated and nonsegregated groups of adults and aggregated at the country level. The ratio of segregation and nonsegregation specific indicators (relative risk, RR) was computed with the corresponding 95% confidence intervals (95% CI). Results: Broad variations between GMPs were detected for each indicator. Segregated groups had a significantly higher rate of health care service use than complementary groups (RR = 1.22, 95% CI: 1.219;1.223) while suffering from significantly reduced health care reimbursement (RR = 0.940, 95% CI: 0.929;0.951). The risk of premature mortality was significantly higher among segregated patients (RR = 1.184, 95% CI: 1.087;1.289). Altogether, living in a segregated area led to an increase in visits to health care services by 18.1% with 6.6% less health spending. Conclusion: Adults living in segregated areas use health care services more frequently than those living in nonsegregated areas; however, the amount of health care reimbursement they receive is significantly lower, suggesting lower quality of care. The health status of segregated adults is remarkably lower, as evidenced by their higher premature mortality rate. These findings demonstrate the need for intervention in this vulnerable group. Because our study reveals serious variation across GMPs, segregation-specific monitoring is necessary to support programs sensitive to local issues and establish necessary benchmarks.


Assuntos
Atenção à Saúde , Guanosina Monofosfato , Tionucleotídeos , Humanos , Adulto , Estudos Transversais , Hungria , Europa (Continente)
3.
Nat Commun ; 15(1): 1860, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424057

RESUMO

Cyclic dimeric guanosine monophosphate (c-di-GMP) serves as a bacterial second messenger that modulates various processes including biofilm formation, motility, and host-microbe symbiosis. Numerous studies have conducted comprehensive analysis of c-di-GMP. However, the mechanisms by which certain environmental signals such as iron control intracellular c-di-GMP levels are unclear. Here, we show that iron regulates c-di-GMP levels in Pseudomonas aeruginosa by modulating the interaction between an iron-sensing protein, IsmP, and a diguanylate cyclase, ImcA. Binding of iron to the CHASE4 domain of IsmP inhibits the IsmP-ImcA interaction, which leads to increased c-di-GMP synthesis by ImcA, thus promoting biofilm formation and reducing bacterial motility. Structural characterization of the apo-CHASE4 domain and its binding to iron allows us to pinpoint residues defining its specificity. In addition, the cryo-electron microscopy structure of ImcA in complex with a c-di-GMP analog (GMPCPP) suggests a unique conformation in which the compound binds to the catalytic pockets and to the membrane-proximal side located at the cytoplasm. Thus, our results indicate that a CHASE4 domain directly senses iron and modulates the crosstalk between c-di-GMP metabolic enzymes.


Assuntos
Proteínas de Bactérias , GMP Cíclico/análogos & derivados , Proteínas de Escherichia coli , Inosina Monofosfato/análogos & derivados , Tionucleotídeos , Proteínas de Bactérias/metabolismo , Pseudomonas aeruginosa/metabolismo , Microscopia Crioeletrônica , Proteínas de Escherichia coli/metabolismo , GMP Cíclico/metabolismo , Biofilmes , Regulação Bacteriana da Expressão Gênica
4.
Biomacromolecules ; 25(3): 2024-2032, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38393758

RESUMO

α-Glucan microparticles (GMPs) have significant potential as high-value biomaterials in various industries. This study proposes a bottom-up approach for producing GMPs using four amylosucrases from Bifidobacterium sp. (BASs). The physicochemical characteristics of these GMPs were analyzed, and the results showed that the properties of the GMPs varied depending on the type of enzymes used in their synthesis. As common properties, all GMPs exhibited typical B-type crystal patterns and poor colloidal dispersion stability. Interestingly, differences in the physicochemical properties of GMPs were generated depending on the synthesis rate of linear α-glucan by the enzymes and the degree of polymerization (DP) distribution. Consequently, we found differences in the properties of GMPs depending on the DP distribution of linear glucans prepared with four BASs. Furthermore, we suggest that precise control of the type and characteristics of the enzymes provides the possibility of producing GMPs with tailored physicochemical properties for various industrial applications.


Assuntos
Bifidobacterium , Glucanos , Guanosina Monofosfato , Tionucleotídeos , Glucanos/química , Glucosiltransferases
5.
Mol Biol Rep ; 51(1): 140, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236447

RESUMO

BACKGROUND: Cyclic guanosine monophosphate (cGMP)-dependent protein kinase I (PKG-I), a serine/threonine kinase, is important in tumor development. The present study determines that the cGMP/PKG I pathway is essential for promoting cell proliferation and survival in human ovarian cancer cells, whereas cGMP analog has been shown to lead to growth inhibition and apoptosis of various cancer cells. The role of cGMP/PKG I pathway in epithelial ovarian cancer (EOC), therefore, remains controversial. We investigated the effect of cGMP/PKG I pathway and the underlying mechanism in EOC. METHODS AND RESULTS: The results showed that exogenous 8-Bromoguanosine-3', 5'-cyclic monophosphate (8-Br-cGMP) (cGMP analog) could antagonize the effects by EGF, including suppressing proliferation, invasion and migration of EOC cells. In vivo, 8-Br-cGMP hampered the growth of the xenograft tumor. Additionally, the expressions of epidermal growth factor receptor (EGFR), matrix metallopeptidase 9 (MMP9), proliferating cell nuclear antigen and Ki67 in xenograft tumor were decreased after 8-Br-cGMP intervention. Further research demonstrated that 8-Br-cGMP decreased the phosphorylation of EGFR (Y992) and downstream proteins phospholipase Cγ1 (PLC γ1) (Y783), calmodulin kinase II (T286) and inhibited cytoplasmic Ca2+ release as well as PKC transferring to cell membrane. It's worth noting that the inhibition was 8-Br-cGMP dose-dependent and 8-Br-cGMP showed similar inhibitory effect on EOC cells compared with U-73122, a specific inhibitor of PLC γ1. CONCLUSIONS: The activation of endogenous PKG I by addition of exogenous 8-Br-cGMP could inhibit EOC development probably via EGFR/PLCγ1 signaling pathway. 8-Br-cGMP/PKG I provide a new insight and strategy for EOC treatment.


Assuntos
GMP Cíclico/análogos & derivados , Neoplasias Ovarianas , Tionucleotídeos , Humanos , Feminino , Carcinoma Epitelial do Ovário , Fosfolipase C gama , Neoplasias Ovarianas/tratamento farmacológico , Receptores ErbB
6.
J Biol Chem ; 300(1): 105509, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042493

RESUMO

Today, the majority of patients with pediatric B cell precursor acute lymphoblastic leukemia (BCP-ALL, hereafter ALL) survive their disease, but many of the survivors suffer from life-limiting late effects of the treatment. ALL develops in the bone marrow, where the cells are exposed to cAMP-generating prostaglandin E2. We have previously identified the cAMP signaling pathway as a putative target for improved efficacy of ALL treatment, based on the ability of cAMP signaling to reduce apoptosis induced by DNA damaging agents. In the present study, we have identified the antioxidant N-acetyl cysteine (NAC) as a powerful modifier of critical events downstream of the cell-permeable cAMP analog 8-(4-chlorophenylthio) adenosine-3', 5'- cyclic monophosphate (8-CPT). Accordingly, we found NAC to turn 8-CPT into a potent killer of ALL cells in vitro both in the presence and absence of DNA damaging treatment. Furthermore, we revealed that NAC in combination with 8-CPT is able to delay the progression of ALL in a xenograft model in NOD-scid IL2Rγnull mice. NAC was shown to rely on the ability of 8-CPT to activate the guanine-nucleotide exchange factor EPAC, and we demonstrated that the ALL cells are killed by apoptosis involving sustained elevated levels of calcium imposed by the combination of the two drugs. Taken together, we propose that 8-CPT in the presence of NAC might be utilized as a novel strategy for treating pediatric ALL patients, and that this powerful combination might be exploited to enhance the therapeutic index of current ALL targeting therapies.


Assuntos
Acetilcisteína , AMP Cíclico , Fatores de Troca do Nucleotídeo Guanina , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Tionucleotídeos , Animais , Criança , Humanos , Camundongos , Acetilcisteína/farmacologia , Acetilcisteína/uso terapêutico , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , AMP Cíclico/uso terapêutico , DNA/efeitos dos fármacos , Fatores de Troca do Nucleotídeo Guanina/agonistas , Camundongos Endogâmicos NOD , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Masculino , Feminino , Pré-Escolar , Tionucleotídeos/farmacologia , Tionucleotídeos/uso terapêutico , Dano ao DNA , Quimioterapia Combinada
7.
Environ Pollut ; 343: 123175, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142031

RESUMO

A declining trend in Indian summer monsoon precipitation (ISMP) in the latter half of the 20th century is a scientifically challenging and societally relevant research issue. Heavy aerosol loading over India is one of the key factors in modulating the ISMP. Using the state-of-the-state-of-the-art chemistry-climate model, ECHAM6-HAMMOZ, the impacts of South Asian anthropogenic sulfate aerosols on the Indian summer monsoon precipitation were investigated against: (1) 2010 La Niña (excess monsoon), (2) 2015 El Niño (deficit monsoon) in comparison to (3) normal monsoon 2016. Sensitivity simulations were designed with 48% enhancement in South Asian SO2 emissions based on a trend estimated from Ozone Monitoring Instrument (OMI) satellite observations during 2006-2017. The model simulations showed that sulfate aerosols reduce ISMP by 27.5%-43.3 %, while simulations without sulfate loading enhanced ISMP by 23% in 2010 La Niña and reduction by 35% in 2015 El Niño. This paper reports that sulfate aerosols loading over India reduce precipitation by aerosol-induced direct and indirect effects by inducing atmospheric cooling, weakening in the convection, and reduction in moisture transport to Indian landmass. This paper emphasizes the necessity of alternate use of energy to reduce sulfate aerosol emissions to solve water issues in South Asia.


Assuntos
Poluentes Atmosféricos , Inosina Monofosfato/análogos & derivados , Sulfatos , Tionucleotídeos , Poluentes Atmosféricos/análise , Estações do Ano , Aerossóis/análise
8.
Br J Clin Pharmacol ; 89(8): 2625-2630, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37218386

RESUMO

About 15% to 28% of patients treated with thiopurines experienced adverse drug reactions, such as haematological and hepatic toxicities. Some of these related to the polymorphic activity of the thiopurine S-methyltransferase (TPMT), the key detoxifying enzyme of thiopurine metabolism. We report here a case of thiopurine-induced ductopenia with a comprehensive pharmacological analysis on thiopurine metabolism. A 34-year-old woman, with a medical history of severe systemic lupus erythematosus with recent introduction of azathioprine therapy, presented with mild fluctuating transaminase blood levels consistent with a hepatocellular pattern, which evolved to a cholestatic pattern over the next weeks. A blood thiopurine metabolite assay revealed low 6-thioguanine nucleotides (6-TGN) level and a dramatically increased 6-methylmercaptopurine ribonucleotides (6-MMPN) level, together with an unfavourable [6-MMPN:6-TGN] metabolite ratio and a high TPMT activity. After a total of about 6 months of thiopurine therapy, a transjugular liver biopsy revealed a ductopenia, and azathioprine discontinuation led to further clinical improvement. In line with previous reports from the literature, our case supports the fact that ductopenia is a rare adverse drug reaction of azathioprine. The mechanism of reaction is unknown but may involve high 6-MMPN blood level, due to unusual thiopurine metabolism (switched metabolism). Early therapeutic drug monitoring with measurement of 6-TGN and 6-MMPN blood levels may help physicians to identify patients at risk of similar duct injury.


Assuntos
Azatioprina , Lúpus Eritematoso Sistêmico , Feminino , Humanos , Adulto , Azatioprina/efeitos adversos , Imunossupressores , Tioguanina/metabolismo , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Tionucleotídeos , Metiltransferases/metabolismo , Ductos Biliares/metabolismo , Mercaptopurina/uso terapêutico , Nucleotídeos de Guanina/metabolismo
9.
Biotechniques ; 73(6): 281-287, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36350046

RESUMO

This study sought to develop a short DNA detection method using a deoxyuridine probe and polymerase chain reaction. The probe was hybridized to the target short DNA, which was then extended by DNA polymerase. The extended DNA was used for real-time PCR after the probe was removed by uracil DNA glycosylase. This method measured from 0.01 to 10 nM of a model short DNA sequence of 17 nucleotides. The method was then used to detect the nucleic acid medicine fomivirsen, as well as 21 phosphorothioate nucleotides, and to quantify 0.1-100 nM of fomivirsen. This method may be useful for detecting short DNA fragments, such as functional nucleotides.


Assuntos
DNA , Tionucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , DNA/genética , Desoxiuridina
10.
Aging Cell ; 21(9): e13699, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36016499

RESUMO

Hypertension is common in elderly population. We designed to search comprehensively for genes that are chronologically shifted in their expressions and to define their contributions to vascular aging and hypertension. RNA sequencing was conducted to search for senescence-shifted transcripts in human umbilical vein endothelial cells (HUVECs). Small interfering RNA (siRNA), small-molecule drugs, CRISPR/Cas9 techniques, and imaging were used to determine genes' function and contributions to age-related phenotypes of the endothelial cell and blood vessel. Of 25 genes enriched in the term of "regulation of blood pressure," NPRA was changed most significantly. The decreased NPRA expression was replicated in aortas of aged mice. The knockdown of NPRA promoted HUVEC senescence and it decreased expressions of protein kinase cGMP-dependent 1 (PKG), sirtuin 1 (SIRT1), and endothelial nitric oxide synthase (eNOS). Suppression of NPRA also decreased the phosphorylation of AMP-activated protein kinase (AMPK) as well as the ratio of oxidized nicotinamide adenine dinucleotide (NAD+ )/reduced nicotinamide adenine dinucleotide (NADH) but increased the production of reactive oxygen species (ROS). 8-Br-cGMP (analog of cGMP), or AICAR (AMPK activator), counteracted the observed changes in HUVECs. The Npr1+/- mice presented an elevated systolic blood pressure and their vessels became insensitive to endothelial-dependent vasodilators. Further, vessels from Npr1+/- mice increased Cdkn1a but decreased eNos expressions. These phenotypes were rescued by intravenously administrated 8-Br-cGMP and viral overexpression of human PKG, respectively. In conclusion, we demonstrate NPRA/PKG/AMPK as a novel and critical signaling axis in the modulation of endothelial cell senescence, vascular aging, and hypertension.


Assuntos
Proteínas Quinases Ativadas por AMP , Hipertensão , Proteínas Quinases Ativadas por AMP/metabolismo , Idoso , Envelhecimento , Animais , Pressão Sanguínea , Células Cultivadas , GMP Cíclico/análogos & derivados , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Camundongos , NAD/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação , RNA Interferente Pequeno/metabolismo , Tionucleotídeos
11.
Int J Pharm ; 625: 122074, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-35932928

RESUMO

G3139 is an antisense oligodeoxyribonucleotide (ODN) developed as a Bcl-2 down-regulating agent for the treatment of acute myelogenous leukemia (AML). However, the clinical efficacy of G3139 has been shown to be limited due to its rapid plasma clearance and low permeability. To enhance the effective delivery of G3139, this work prepared a novel nano gene delivery vector (aCD33-NKSN) consisting of a CD33 antigbody (aCD33), a nuclear localization signal (NLS), gene fusion peptides (KALA), and stearic acid (SA) for CD33 antigen targeting and nuclear localization. The aCD33-NKSN/G3139 nanoparticles were spherical and uniformly sized with a positive charge and sustained release. They had an excellent G3139 loading capacity and colloidal stability. The aCD33-NKSN/G3139 delivered G3139 into the nucleus of Kasumi-1 cells and aCD33-NKSN/G3139 could more effectively inhibited Bcl-2 expression and induced apoptosis in Kasumi-1 cells versus free G3139. The aCD33-NKSN/G3139 administration was more effective at inhibiting tumor growth, and significantly prolonged the survival time of mice in contrast to free G3139. The results illustrate that aCD33-NKSN/G3139 nanoparticles could improve the antitumor activity of encapsulated G3139 due to aCD33 targeting and the ability to perform nuclear localization, The results offer a promising clinical application potential for the treatment of acute myeloid leukemia.


Assuntos
Leucemia Mieloide Aguda , Nanopartículas , Animais , Linhagem Celular Tumoral , Leucemia Mieloide Aguda/tratamento farmacológico , Camundongos , Oligonucleotídeos , Oligonucleotídeos Antissenso , Proteínas Proto-Oncogênicas c-bcl-2/genética , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico , Tionucleotídeos
12.
J Appl Microbiol ; 133(4): 2599-2617, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35870146

RESUMO

AIMS: The aim was to isolate a neotype bifidobacteria strain and evaluate its in vitro probiotic potential. METHODS AND RESULTS: Bifidobacterium pseudolongum YY-26 (CGMCC 24310) was isolated from faeces of mice treated with low-molecular-weight hydrolyzed guar gum (GMPS) and identified based on 16S rRNA sequence and genome sequence. Whole-genome sequencing obtained using PacBio's single-molecular and Illumina's paired-end sequencing technology. A genome of 2.1 Mb in length, with 1877 predicted protein-coding sequences was obtained. Carbohydrate-Activity enZyme analysis revealed that YY-26 encodes 66 enzymes related to carbohydrate metabolism. Whole genome sequence analysis revealed the typical probiotic characteristics of YY-26, including safety in genetic level and ability to produce beneficial metabolites and extracellular polysaccharides. Ability of extensive carbon source utilization and short-chain fatty acid production was observed with single YY-26 cultivation. Considerable acetic acids and lactic acids were determined in GMPS utilization. YY-26 showed tolerance to simulated gastrointestinal tract and displayed appreciable antioxidant activity of free radical scavenging. CONCLUSIONS: B. pseudolongum YY-26 was identified with numerous probiotic-associated genes and its probiotic characteristics were verified in vitro. SIGNIFICANCE AND IMPACT OF STUDY: This study supplemented with limited publicly information regarding the genomes of B. pseudolongum strains and revealed the probiotic potential of YY-26.


Assuntos
Antioxidantes , Probióticos , Animais , Bifidobacterium , Carboidratos , Carbono , Ácidos Graxos Voláteis , Radicais Livres , Guanosina Monofosfato , Camundongos , RNA Ribossômico 16S/genética , Tionucleotídeos
13.
Platelets ; 33(8): 1301-1306, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-35514261

RESUMO

Platelet activation by adenosine diphosphate (ADP) is mediated through two G-protein-coupled receptors, P2Y1 and P2Y12, which signal through Gq and Gi, respectively. P2Y1 stimulation leads to phospholipase C activation and an increase in cytosolic calcium necessary for CalDAG-GEF1 activation. Engagement of P2Y12 inhibits adenylate cyclase, which reduces cAMP, and activation of PI3-kinase, which inhibits RASA3 resulting in sustained activated Rap1b. In this study we activated human platelets with 2-MeSADP in the presence of LY294002, a PI3-kinase inhibitor, AR-C69931MX, a P2Y12 antagonist or MRS2179, a P2Y1 antagonist. We measured the phosphorylation of Akt on Ser473 as an indicator of PI3-kinase activity. As previously shown, LY294002 and ARC69931MX abolished 2MeSADP-induced Akt phosphorylation. MRS2179 reduced ADP-induced Akt phosphorylation but did not abolish it. Rap1b activation, however, was only reduced, but not ablated, using LY294002 and was completely inhibited by ARC69931MX or MRS2179. Furthermore, 2MeSADP-induced Rap1b activation was abolished in either P2Y1 or P2Y12 null platelets. These data suggest that ADP-induced Rap1b activation requires both P2Y1 and P2Y12. In addition, although stimulation of P2Y12 results in PI3-kinase activation leading to Akt phosphorylation and Rap1b activation, Rap1b activation can occur independently of PI3-kinase downstream of P2Y12. Thus, we propose that the P2Y12 receptor can regulate Rap1b, possibly through RASA3, in a pathway independent of PI3-kinase.


Assuntos
Fosfatidilinositol 3-Quinases , Receptores Purinérgicos P2 , Difosfato de Adenosina/análogos & derivados , Difosfato de Adenosina/metabolismo , Difosfato de Adenosina/farmacologia , Adenilil Ciclases/metabolismo , Plaquetas/metabolismo , Cálcio/metabolismo , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antagonistas do Receptor Purinérgico P2Y , Receptores Purinérgicos P2/metabolismo , Receptores Purinérgicos P2Y1/metabolismo , Receptores Purinérgicos P2Y12/metabolismo , Tionucleotídeos , Fosfolipases Tipo C/metabolismo , Proteínas rap de Ligação ao GTP/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-35565071

RESUMO

BACKGROUND: The Standardized Residency Training Program (SRTP) is a significant initiative to deepen health systems and medical education in developing countries like China. Despite the promotion of the SRTP nationwide and its implementation with various improvements, Chinese continuous medical education is still in its infancy. Compared with the residents, little is known about clinical teachers under the SRTP in China. However, clinical teachers effectively determine the training quality as critical disseminators of knowledge, skills, and values in medical practice. Thus, the study aims to analyze critical factors affecting their cognitive job satisfaction and provide continuous improvements for SRTP. METHODS: From 1 December 2018 to 31 May 2019, we conducted a self-designed questionnaire with 13 SRTPs (including both training bases and professional bases) in Shaoxing city to evaluate clinical teachers' satisfaction. Altogether, 574 clinical teachers responded to the survey expressing generally high overall satisfaction. We adopted a Chi-square test and Fisher's Exact Test to evaluate the single impact factors affecting the satisfaction of clinical teachers. The multiple factors analysis applied the logistic regression model. RESULTS: The male clinical teachers had significant differences in satisfaction with the teaching content (OR: 0.675, [95% CI: 0.477~0.953]), conflicts between study and work (OR: 0.542, [95%CI: 0.371~0.791]), the attention of leaders (OR: 0.403, [95%CI: 0.252~0.645]), and the subsidies of teachers (OR: 0.527, [95%CI: 0.347~0.805]). Compared with internal medicine, clinical teachers from surgery (OR: 2.396, [95%CI: 1.365-4.206]) and other departments (OR: 2.409, [95%CI: 1.406-4.129]) were more satisfied when they considered that residents have high motivation to attend training. In addition, compared with the attending physicians, the deputy chief physicians (OR: 0.493, [95%CI: 0.310-0.783]) and the chief physicians (OR: 0.683, [95%CI: 0.471-0.991]) disagreed more regarding the residents' wage being good enough. CONCLUSION: Clinical teachers widely recognize the SRTP. However, teachers' satisfaction varied due to different genders, working departments, and professional titles. The study also discussed possible reasons and strategy implications behind these findings, which combined unique Chinese society characteristics. Further, we believe the analysis and interpretations remind us of the applications of residency training methods from other Western countries, which should also consider the unique socio-cultural challenges.


Assuntos
Internato e Residência , China , Estudos Transversais , Feminino , Humanos , Satisfação no Emprego , Masculino , Satisfação Pessoal , Inquéritos e Questionários , Tionucleotídeos
15.
Br J Clin Pharmacol ; 88(8): 3741-3748, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35293629

RESUMO

AIMS: The effect of the Dutch nationwide adjustment of reducing 6-thioguanine nucleotide (6-TGN) target values (from 600-1200 to 320-630 pmol/8 × 108 red blood cells [RBC]) on toxicity and clinical outcome of thiopurine treatment in patients with inflammatory bowel disease has not yet been established. Therefore, the authors determined the incidence of toxicity-induced discontinuations and efficacy at both target concentrations. METHODS: This retrospective study was performed in inflammatory bowel disease patients treated with azathioprine or mercaptopurine. Two groups were defined: the former target (FT) group with target concentrations of 600-1200 pmol/8 × 108 RBC and the adjusted target (AT) group with target concentrations of 320-630 pmol/8 × 108 RBC. Patients were followed for maximum 52 weeks or until discontinuation of thiopurine therapy. Data were collected from the local hospital electronic health software of Rijnstate Hospital. RESULTS: In total, 151 patients were included, 76 in the FT group and 75 in the AT group. At week 52, 100 out of 151 patients (66%) of the total population discontinued thiopurine therapy. Forty-eight of the discontinuations were due toxicity (48%). The incidence of toxicity induced discontinuations was 35% in the AT group vs. 47% in the FT group (P = .25). No loss of efficacy was seen in the AT group. CONCLUSION: After reduction of the target range, there was a trend towards fewer toxicity-induced discontinuations, albeit not statistically significant. In addition, this study did not find any indication that the reduction of the target range diminished efficacy.


Assuntos
Doenças Inflamatórias Intestinais , Tioguanina , Azatioprina/efeitos adversos , Monitoramento de Medicamentos , Nucleotídeos de Guanina/uso terapêutico , Humanos , Imunossupressores/efeitos adversos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mercaptopurina , Nucleotídeos/uso terapêutico , Estudos Retrospectivos , Tioguanina/efeitos adversos , Tionucleotídeos
16.
J Am Chem Soc ; 144(7): 2953-2967, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35164499

RESUMO

The voltage-dependent anion channel (VDAC), the most abundant protein in the outer mitochondrial membrane, is responsible for the transport of all ions and metabolites into and out of mitochondria. Larger than any of the ß-barrel structures determined to date by magic-angle spinning (MAS) NMR, but smaller than the size limit of cryo-electron microscopy (cryo-EM), VDAC1's 31 kDa size has long been a bottleneck in determining its structure in a near-native lipid bilayer environment. Using a single two-dimensional (2D) crystalline sample of human VDAC1 in lipids, we applied proton-detected fast magic-angle spinning NMR spectroscopy to determine the arrangement of ß strands. Combining these data with long-range restraints from a spin-labeled sample, chemical shift-based secondary structure prediction, and previous MAS NMR and atomic force microscopy (AFM) data, we determined the channel's structure at a 2.2 Å root-mean-square deviation (RMSD). The structure, a 19-stranded ß-barrel, with an N-terminal α-helix in the pore is in agreement with previous data in detergent, which was questioned due to the potential for the detergent to perturb the protein's functional structure. Using a quintuple mutant implementing the channel's closed state, we found that dynamics are a key element in the protein's gating behavior, as channel closure leads to the destabilization of not only the C-terminal barrel residues but also the α2 helix. We showed that cholesterol, previously shown to reduce the frequency of channel closure, stabilizes the barrel relative to the N-terminal helix. Furthermore, we observed channel closure through steric blockage by a drug shown to selectively bind to the channel, the Bcl2-antisense oligonucleotide G3139.


Assuntos
Bicamadas Lipídicas/metabolismo , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Sítios de Ligação , Colesterol/química , Colesterol/metabolismo , Humanos , Ativação do Canal Iônico , Ligantes , Mutação , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Tionucleotídeos/química , Tionucleotídeos/metabolismo , Canal de Ânion 1 Dependente de Voltagem/química , Canal de Ânion 1 Dependente de Voltagem/genética
17.
Arch Pharm (Weinheim) ; 355(4): e2100441, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35099085

RESUMO

Microbial strains isolated from extreme and understudied environments, such as caves, are still poorly investigated for the production of bioactive secondary metabolites. Investigation of the ethyl acetate extract from the growth medium produced by the soil-derived fungus Aspergillus sp. SDC28, isolated from a Brazilian cave, yielded two anthraquinones: versicolorin C (1) and versiconol (2). The complete assignment of nuclear magnetic resonance and mass spectroscopic data of 1 and 2 was performed for the first time. Moreover, the yet unreported absolute configuration of both compounds was unambiguously established by analysis of experimental and theoretical electronic circular dichroism data. Vibrational circular dichroism was also applied to confirm the absolute stereochemistry of 2. Compounds 1 and 2 showed cytotoxic activity against human ovarian cancer cells (OVCAR3).


Assuntos
Cavernas , Neoplasias Ovarianas , Antraquinonas/farmacologia , Apoptose , Aspergillus/química , Aspergillus/metabolismo , Brasil , Linhagem Celular Tumoral , Dicroísmo Circular , Feminino , Humanos , Estrutura Molecular , Oligodesoxirribonucleotídeos , Solo , Relação Estrutura-Atividade , Tionucleotídeos
18.
Ther Drug Monit ; 44(3): 391-395, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35067667

RESUMO

BACKGROUND: Although the relationship between NUDT15 and thiopurine-induced leukopenia has been proven in previous studies, no prominent factors explaining interindividual variations in its active metabolite, 6-thioguanine nucleotide (6-TGN), and clinical efficacy have been identified. In this study, the correlation between genotypes (thiopurine S-methyltransferase, NUDT15, and ITPA polymorphisms), 6-TGN concentrations, and clinical outcomes (efficacy and side effects) in patients with inflammatory bowel disease were investigated. METHODS: In total, 160 patients with inflammatory bowel disease were included, and the 3 genotyped genes and 6-TGN levels were measured by high-performance liquid chromatography. Statistical analyses and calculations were performed to determine their relationships. RESULTS: ITPA genotypes and 6-TGN concentration were both associated with the clinical effectiveness of azathioprine (P = 0.036 and P = 4.6 × 10-7), with a significant correlation also detected between them (P = 0.042). Patients with ITPA variant alleles exhibited higher 6-TGN levels than those with the wild-type allele. In addition, the relationship between NUDT15 and leukopenia and neutropenia was confirmed (P = 1.79 × 10-7 and 0.002). CONCLUSIONS: In summary, it is recommended that both ITPA and NUDT15 genotyping should be performed before azathioprine initiation. Moreover, the 6-TGN concentration should be routinely monitored during the later period of treatment.


Assuntos
Doenças Inflamatórias Intestinais , Pirofosfatases , Azatioprina/uso terapêutico , Biomarcadores/metabolismo , China , Nucleotídeos de Guanina/genética , Nucleotídeos de Guanina/metabolismo , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Leucopenia/induzido quimicamente , Leucopenia/tratamento farmacológico , Leucopenia/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Prognóstico , Pirofosfatases/genética , Pirofosfatases/metabolismo , Tionucleotídeos/genética , Tionucleotídeos/metabolismo
19.
J Nucl Cardiol ; 29(5): 2571-2579, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34414552

RESUMO

BACKGROUND: It had not been reported that myocardial scar shown on gated myocardial perfusion SPECT (GMPS) might reduce after cardiac resynchronization therapy (CRT). In this study, we aim to investigate the clinical impact and characteristic of scar reduction (SR) after CRT. METHODS AND RESULTS: Sixty-one heart failure patients following standard indication for CRT received twice GMPS as pre- and post-CRT evaluations. The patients with an absolute reduction of scar ≥ 10% after CRT were classified as the SR group while the rest were classified as the non-SR group. The SR group (N = 22, 36%) showed more improvement on LV function (∆LVEF: 18.1 ± 12.4 vs 9.4 ± 9.9 %, P = 0.007, ∆ESV: - 91.6 ± 52.6 vs - 38.1 ± 46.5 mL, P < 0.001) and dyssynchrony (ΔPSD: - 26.19 ± 18.42 vs - 5.8 ± 23.0°, P < 0.001, Δ BW: - 128.7 ± 82.8 vs - 25.2 ± 109.0°, P < 0.001) than non-SR group (N = 39, 64%). Multivariate logistic regression analysis showed baseline QRSd (95% CI 1.019-1.100, P = 0.006) and pre-CRT Reduced Wall Thickening (RWT) (95% CI 1.016-1.173, P = 0.028) were independent predictors for the development of SR. CONCLUSION: More than one third of patients showed SR after CRT who had more post-CRT improvement on LV function and dyssynchrony than those without SR. Wider QRSd and higher RWT before CRT were related to the development of SR after CRT.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Imagem de Perfusão do Miocárdio , Terapia de Ressincronização Cardíaca/métodos , Cicatriz/diagnóstico por imagem , Guanosina Monofosfato , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/terapia , Humanos , Imagem de Perfusão do Miocárdio/métodos , Perfusão , Tionucleotídeos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Resultado do Tratamento
20.
Dig Dis Sci ; 67(1): 241-251, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33532972

RESUMO

BACKGROUND: In the recent era of growing availability of biological agents, the role of thiopurines needs to be reassessed with the focus on toxicity. AIMS: We assessed the incidence and predictive factors of thiopurine-induced adverse events (AE) resulting in therapy cessation in pediatric inflammatory bowel disease (IBD), related to thiopurine metabolites and biochemical abnormalities, and determined overall drug survival. METHODS: We performed a retrospective, single-center study of children diagnosed with IBD between 2000 and 2019 and treated with thiopurine therapy. The incidence of AE and overall drug survival of thiopurines were evaluated using the Kaplan-Meier method. Correlations between thiopurine metabolites and biochemical tests were computed using Spearman's correlation coefficient. RESULTS: Of 391 patients with IBD, 233 patients (162 Crohn's disease, 62 ulcerative colitis, and 9 IBD-unclassified) were prescribed thiopurines (230 azathioprine and 3 mercaptopurine), of whom 50 patients (22%) discontinued treatment, at least temporary, due to thiopurine-induced AE (median follow-up 20.7 months). Twenty-six patients (52%) were rechallenged and 18 of them (70%) tolerated this. Sixteen patients (6%) switched to a second thiopurine agent after azathioprine intolerance and 10 of them (63%) tolerated this. No predictive factors for development of AE could be identified. Concentrations of 6-thioguanine nucleotides (6-TGN) were significantly correlated with white blood cell and neutrophil count, 6-methylmercaptopurine (6-MMP) concentrations with alanine aminotransferase and gamma-glutamyltranspeptidase. CONCLUSIONS: Approximately 20% of pediatric patients with IBD discontinued thiopurine treatment due to AE. A rechallenge or switch to mercaptopurine is an effective strategy after development of AE. Concentrations of 6-TGN and 6-MMP are associated with biochemical abnormalities.


Assuntos
Azatioprina , Colite Ulcerativa , Doença de Crohn , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Mercaptopurina/análogos & derivados , Suspensão de Tratamento/estatística & dados numéricos , Adolescente , Antimetabólitos/administração & dosagem , Antimetabólitos/efeitos adversos , Antimetabólitos/farmacocinética , Azatioprina/administração & dosagem , Azatioprina/efeitos adversos , Azatioprina/farmacocinética , Biomarcadores Farmacológicos/sangue , Criança , Estudos de Coortes , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Doença de Crohn/tratamento farmacológico , Doença de Crohn/epidemiologia , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Substituição de Medicamentos/métodos , Substituição de Medicamentos/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Feminino , Nucleotídeos de Guanina/sangue , Humanos , Masculino , Mercaptopurina/administração & dosagem , Mercaptopurina/efeitos adversos , Mercaptopurina/farmacocinética , Países Baixos/epidemiologia , Estudos Retrospectivos , Tionucleotídeos/sangue
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