Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 206
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
J Immunol ; 213(7): 1008-1022, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39194407

RESUMO

The functions of the natural dsRNA sensors TLR3 (TRIF) and RIG-I (MAVS) are crucial during viral challenge and have not been accurately clarified in adaptive immune responses to rotavirus (RV) infection. In this study, we found that RV infection caused severe pathological damage to the small intestine of TLR3-/- and TRIF-/- mice. Our data found that dendritic cells from TLR3-/- and TRIF-/- mice had impaired Ag presentation to the RV and attenuated initiation of T cells upon viral infection. These attenuated functions resulted in impaired CD4+ T and CD8+ T function in mice lacking TLR3-TRIF signaling postinfection. Additionally, attenuated proliferative capacity of T cells from TLR3-/- and TRIF-/- mice was observed. Subsequently, we observed a significant reduction in the absolute number of memory T cells in the spleen and mesenteric lymph node (MLN) of TRIF-/- recipient mice following RV infection in a bone marrow chimeric model. Furthermore, there was reduced migration of type 2 classical dendritic cells from the intestine to MLNs after RV infection in TLR3-/- and TRIF-/- mice. Notably, RV infection resulted in attenuated killing of spleen and MLN tissues in TRIF-/- and MAVS-/- mice. Finally, we demonstrated that RV infection promoted apoptosis of CD8+ T cells in TRIF-/- and TLR3-/-MAVS-/- mice. Taken together, our findings highlight an important mechanism of TLR3 signaling through TRIF in mucosal T cell responses to RV and lay the foundation for the development of a novel vaccine.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Adaptadoras de Transporte Vesicular , Células Dendríticas , Camundongos Knockout , Infecções por Rotavirus , Rotavirus , Transdução de Sinais , Receptor 3 Toll-Like , Animais , Receptor 3 Toll-Like/imunologia , Camundongos , Infecções por Rotavirus/imunologia , Transdução de Sinais/imunologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Rotavirus/imunologia , Células Dendríticas/imunologia , Camundongos Endogâmicos C57BL , Mucosa Intestinal/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunidade nas Mucosas , Apresentação de Antígeno/imunologia
2.
J Cardiovasc Pharmacol ; 84(1): 118-123, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38547516

RESUMO

ABSTRACT: This study seeks to identify the anticoagulant efficacy of rivaroxaban treatment on thrombi detected using echocardiography of the left atrial appendage in 275 patients with persistent atrial fibrillation. During follow-up after 9-24 weeks of rivaroxaban treatment, patients were divided into "effective group" (n = 143) and "ineffective group" (n = 132) according to the thrombolytic effect of the drug. Left atrial diameter (LAD), left atrial ejection fraction (LAEF), left ventricular ejection fraction (LVEF), mean diameter of left atrial appendage (LAAD mean ), angle between left atrial appendage and left atrium (LAA-A), velocity of blood flow in left atrial appendage (LAA-v), and thrombus size were compared before and after drug administration. Following treatment, LAEF, LVEF, and LAA-v values were greater and LAD and LAAD mean values were lower in the effective ( P < 0.05). Logistic regression analysis showed significant correlations of LAD, LAEF, LVEF, LAA-A, and LAA-v with anticoagulant efficacy ( P < 0.05). The efficacy of rivaroxaban in treatment of left atrial auricular thrombosis in patients with persistent AF was correlated with LAD, LAEF, LVEF, LAA-A, and LAA-v. Multivariate logistic regression analysis further revealed LAEF [odds ratio (OR) 1.7, 95% confidence interval (CI), 0.45-16.9, P = 0.008], 3D-EF (OR 6.4, 95% CI, 1.06-16.9, P = 0.039) and left ventricular global longitudinal strain (OR 18.0, 95% CI, 1.38-35.68, P = 0.028) as factors related to left atrial appendage thrombus. Echocardiography with global longitudinal strain assessment could be effectively utilized to evaluate the functional parameters of LAA and thus aid in predicting the safety of rivaroxaban as an anticoagulation agent.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Ecocardiografia Tridimensional , Inibidores do Fator Xa , Rivaroxabana , Humanos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/diagnóstico , Feminino , Masculino , Rivaroxabana/uso terapêutico , Rivaroxabana/administração & dosagem , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/fisiopatologia , Apêndice Atrial/efeitos dos fármacos , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/uso terapêutico , Trombose/diagnóstico por imagem , Trombose/tratamento farmacológico , Trombose/fisiopatologia , Valor Preditivo dos Testes , Função do Átrio Esquerdo/efeitos dos fármacos , Terapia Trombolítica , Função Ventricular Esquerda/efeitos dos fármacos , Fatores de Tempo
3.
AIDS Behav ; 28(7): 2183-2192, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38625625

RESUMO

Vaccine hesitancy is one of the top 10 threats to global health, which affects the prevalence and fatality of vaccine-preventable diseases over the world. During the COVID-19 pandemic, people living with HIV (PLWH) may have higher risks of infection, more serious complications, and worse prognosis without the protection of the COVID-19 vaccine. A systematic review and meta-analysis aiming to evaluate the prevalence of COVID-19 vaccine hesitancy among PLWH was conducted using PubMed, Embase, and Web of Science databases for studies published between January 1, 2020, and August 31, 2022. The pooled prevalence with a corresponding 95%CI of COVID-19 vaccine hesitancy among PLWH was reported. Subgroup analysis was conducted to explore variation in prevalence across different categories. 23 studies with a total of 19,922 PLWH were included in this study. The prevalence of COVID-19 vaccine hesitancy among PLWH was 34.0%, and the influencing factors included male, influenza vaccination experience, and a CD4 count of more than 200 cells/mm3. Subgroup analysis did not identify significant causes of heterogeneity but showed that the prevalence of COVID-19 vaccine hesitancy among PLWH varies by study period, region, and race. Although all PLWH are recommended to receive the COVID-19 vaccine, a large proportion of them remain hesitant to be vaccinated. Therefore, governments and relevant institutions should take specific measures to encourage and promote vaccination to improve the coverage of the COVID-19 vaccine among PLWH.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Infecções por HIV , SARS-CoV-2 , Hesitação Vacinal , Feminino , Humanos , Masculino , COVID-19/prevenção & controle , COVID-19/epidemiologia , COVID-19/psicologia , Vacinas contra COVID-19/administração & dosagem , Infecções por HIV/psicologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Vacinação/psicologia , Vacinação/estatística & dados numéricos , Hesitação Vacinal/psicologia , Hesitação Vacinal/estatística & dados numéricos
4.
J Nat Prod ; 87(5): 1416-1425, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38687902

RESUMO

In nature, proanthocyanidins (PACs) with A-type linkages are relatively rare, likely due to biosynthetic constraints in the formation of additional ether bonds to be introduced into the more common B-type precursors. However, A-type linkages confer greater structural rigidity on PACs than do B-type linkages. Prior investigations into the structure-activity relationships (SAR) describing how plant-derived PACs with B- and complex AB-type linkages affect their capacity for dentin biomodification indicate that a higher ratio of double linkages leads to a greater interaction with dentin type I collagen. Thus, A-type PACs emerge as particularly intriguing candidates for interventional functional biomaterials. This study employed a free-radical-mediated oxidation using DPPH to transform trimeric and tetrameric B-type PACs, 2 and 4, respectively, into their exclusively A-type linked analogues, 3 and 5, respectively. The structures and absolute configurations of the semisynthetic products, including the new all-A-type tetramer 5, were determined by comprehensive spectroscopic analysis. Additionally, molecular modeling investigated the conformational characteristics of all trimers and tetramers, 1-5. Our findings suggest that the specific interflavan linkages significantly impact the flexibility and low-energy conformations of the connected monomeric units, which conversely can affect the bioactive conformations relevant for dentin biomodification.


Assuntos
Proantocianidinas , Proantocianidinas/química , Estrutura Molecular , Relação Estrutura-Atividade
5.
Acta Pharmacol Sin ; 45(2): 248-267, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37833536

RESUMO

There are few effective and safe neuroprotective agents for the treatment of ischemic stroke currently. Caffeic acid is a phenolic acid that widely exists in a number of plant species. Previous studies show that caffeic acid ameliorates brain injury in rats after cerebral ischemia/reperfusion. In this study we explored the protective mechanisms of caffeic acid against oxidative stress and ferroptosis in permanent cerebral ischemia. Ischemia stroke was induced on rats by permanent middle cerebral artery occlusion (pMCAO). Caffeic acid (0.4, 2, 10 mg·kg-1·d-1, i.g.) was administered to the rats for 3 consecutive days before or after the surgery. We showed that either pre-pMCAO or post-pMCAO administration of caffeic acid (2 mg·kg-1·d-1) effectively reduced the infarct volume and improved neurological outcome. The therapeutic time window could last to 2 h after pMCAO. We found that caffeic acid administration significantly reduced oxidative damage as well as neuroinflammation, and enhanced antioxidant capacity in pMCAO rat brain. We further demonstrated that caffeic acid down-regulated TFR1 and ACSL4, and up-regulated glutathione production through Nrf2 signaling pathway to resist ferroptosis in pMCAO rat brain and in oxygen glucose deprivation/reoxygenation (OGD/R)-treated SK-N-SH cells in vitro. Application of ML385, an Nrf2 inhibitor, blocked the neuroprotective effects of caffeic acid in both in vivo and in vitro models, evidenced by excessive accumulation of iron ions and inactivation of the ferroptosis defense system. In conclusion, caffeic acid inhibits oxidative stress-mediated neuronal death in pMCAO rat brain by regulating ferroptosis via Nrf2 signaling pathway. Caffeic acid might serve as a potential treatment to relieve brain injury after cerebral ischemia. Caffeic acid significantly attenuated cerebral ischemic injury and resisted ferroptosis both in vivo and in vitro. The regulation of Nrf2 by caffeic acid initiated the transcription of downstream target genes, which were shown to be anti-inflammatory, antioxidative and antiferroptotic. The effects of caffeic acid on neuroinflammation and ferroptosis in cerebral ischemia were explored in a primary microglia-neuron coculture system. Caffeic acid played a role in reducing neuroinflammation and resisting ferroptosis through the Nrf2 signaling pathway, which further suggested that caffeic acid might be a potential therapeutic method for alleviating brain injury after cerebral ischemia.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , Ácidos Cafeicos , Ferroptose , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Animais , Ratos Sprague-Dawley , Fator 2 Relacionado a NF-E2/metabolismo , Doenças Neuroinflamatórias , Transdução de Sinais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Lesões Encefálicas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Antioxidantes/farmacologia , Traumatismo por Reperfusão/metabolismo
6.
Acta Pharmacol Sin ; 45(6): 1142-1159, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38409216

RESUMO

Alzheimer's disease (AD), a progressive neurodegenerative disorder, is the most common cause of dementia in elderly people and substantially affects patient quality of life. Oxidative stress is considered a key factor in the development of AD. Nrf2 plays a vital role in maintaining redox homeostasis and regulating neuroinflammatory responses in AD. Previous studies show that potassium 2-(1-hydroxypentyl)-benzoate (PHPB) exerts neuroprotective effects against cognitive impairment in a variety of dementia animal models such as APP/PS1 transgenic mice. In this study we investigated whether PHPB ameriorated the progression of AD by reducing oxidative stress (OS) damage. Both 5- and 13-month-old APP/PS1 mice were administered PHPB (100 mg·kg-1·d-1, i.g.) for 10 weeks. After the cognition assessment, the mice were euthanized, and the left hemisphere of the brain was harvested for analyses. We showed that 5-month-old APP/PS1 mice already exhibited impaired performance in the step-down test, and knockdown of Nrf2 gene only slightly increased the impairment, while knockdown of Nrf2 gene in 13-month-old APP/PS1 mice resulted in greatly worse performance. PHPB administration significantly ameliorated the cognition impairments and enhanced antioxidative capacity in APP/PS1 mice. In addition, PHPB administration significantly increased the p-AKT/AKT and p-GSK3ß/GSK3ß ratios and the expression levels of Nrf2, HO-1 and NQO-1 in APP/PS1 mice, but these changes were abolished by knockdown of Nrf2 gene. In SK-N-SH APPwt cells and primary mouse neurons, PHPB (10 µM) significantly increased the p-AKT/AKT and p-GSK3ß/GSK3ß ratios and the level of Nrf2, which were blocked by knockdown of Nrf2 gene. In summary, this study demonstrates that PHPB exerts a protective effect via the Akt/GSK3ß/Nrf2 pathway and it might be a promising neuroprotective agent for the treatment of AD.


Assuntos
Doença de Alzheimer , Modelos Animais de Doenças , Transtornos da Memória , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Transdução de Sinais , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Camundongos , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Masculino , Humanos , Camundongos Endogâmicos C57BL
7.
Ann Intern Med ; 176(7): 922-933, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37335994

RESUMO

BACKGROUND: An effective and safe treatment for nausea and vomiting of pregnancy (NVP) is lacking. OBJECTIVE: To assess the efficacy and safety of acupuncture, doxylamine-pyridoxine, and a combination of both in women with moderate to severe NVP. DESIGN: Multicenter, randomized, double-blind, placebo-controlled, 2 × 2 factorial trial. (ClinicalTrials.gov: NCT04401384). SETTING: 13 tertiary hospitals in mainland China from 21 June 2020 to 2 February 2022. PARTICIPANTS: 352 women in early pregnancy with moderate to severe NVP. INTERVENTION: Participants received daily active or sham acupuncture for 30 minutes and doxylamine-pyridoxine or placebo for 14 days. MEASUREMENTS: The primary outcome was the reduction in Pregnancy-Unique Quantification of Emesis (PUQE) score at the end of the intervention at day 15 relative to baseline. Secondary outcomes included quality of life, adverse events, and maternal and perinatal complications. RESULTS: No significant interaction was detected between the interventions (P = 0.69). Participants receiving acupuncture (mean difference [MD], -0.7 [95% CI, -1.3 to -0.1]), doxylamine-pyridoxine (MD, -1.0 [CI, -1.6 to -0.4]), and the combination of both (MD, -1.6 [CI, -2.2 to -0.9]) had a larger reduction in PUQE score over the treatment course than their respective control groups (sham acupuncture, placebo, and sham acupuncture plus placebo). Compared with placebo, a higher risk for births with children who were small for gestational age was observed with doxylamine-pyridoxine (odds ratio, 3.8 [CI, 1.0 to 14.1]). LIMITATION: The placebo effects of the interventions and natural regression of the disease were not evaluated. CONCLUSION: Both acupuncture and doxylamine-pyridoxine alone are efficacious for moderate and severe NVP. However, the clinical importance of this effect is uncertain because of its modest magnitude. The combination of acupuncture and doxylamine-pyridoxine may yield a potentially larger benefit than each treatment alone. PRIMARY FUNDING SOURCE: The National Key R&D Program of China and the Project of Heilongjiang Province "TouYan" Innovation Team.


Assuntos
Terapia por Acupuntura , Antieméticos , Complicações na Gravidez , Gravidez , Criança , Feminino , Humanos , Doxilamina/efeitos adversos , Piridoxina/uso terapêutico , Piridoxina/efeitos adversos , Antieméticos/uso terapêutico , Qualidade de Vida , Vômito/tratamento farmacológico , Vômito/induzido quimicamente , Náusea/tratamento farmacológico , Complicações na Gravidez/tratamento farmacológico , Terapia por Acupuntura/efeitos adversos
8.
Zhongguo Zhong Yao Za Zhi ; 49(2): 498-508, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403325

RESUMO

To fully understand whether Saposhnikoviae Radix polysaccharides(SP) can be metabolized in gastric fluid and the meta-bolic behavior, this study systematically analyzed the metabolites in simulated gastric fluid of SP by high-performance liquid chromatography-ion trap time-of-flight mass spectrometry(HPLC-IT-TOF-MS) technology in combination with zebrafish immune activity evaluation. Based on the obtained accurate relative molecular mass, chromatographic retention behavior, MS fragmentation patterns, refe-rence standards, and relevant literature reports, 19 metabolites were analyzed and identified. Among them, five monosaccharides and 14 oligosaccharides were generated as metabolites. Several reducing sugars, including mannose, glucose, rhamnose, and xylose, were accurately identified in the gastric fluid metabolites. Zebrafish pharmacological evaluation results indicated that SP maintained good immune activity after gastric fluid metabolism, with the most significant increase in immune cell density observed at W3(simulated gastric fluid metabolism for 2 hours). Among the gastric fluid metabolites, M1 and M3(Hex-Hex-Man) may be most closely related to pharmacological activity and could be further studied as potential active fragments.


Assuntos
Medicamentos de Ervas Chinesas , Peixe-Zebra , Humanos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Raízes de Plantas/química , Polissacarídeos/análise , Medicamentos de Ervas Chinesas/química
9.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3591-3599, 2024 Jul.
Artigo em Zh | MEDLINE | ID: mdl-39041131

RESUMO

This study investigated the immunological mechanisms of Ermiao powder in the treatment of rheumatoid arthritis rats through the alpha 7 nicotinic acetylcholine receptor(α7nAChR)-Janus kinases 2(JAK2)/signal transducer and activator of transcription 3(STAT3) signaling pathway. A total of 56 female Wistar rats were randomly divided into the normal group(HG, n=8), collagen-induced arthritis(CIA) model group(CM, n=8), vagotomy group(VA, n=8), sham group(SH, n=8), Ermiao Powder treatment model group(EM, n=8), Ermiao Powder treatment for vagotomy group(EV, n=8) and Ermiao Powder treatment for sham group(ES, n=8). Following the establishment of CIA models in all groups except the HG group, the rats underwent unilateral vagotomy and sham operation(only the vagus nerve was separated). Drug treatment was started 7 days after surgery and continued for 35 days. The body weight and joints of rats were recorded, the pathological changes of the spleen of rats were observed, the contents of interleukin-6(IL-6), interleukin-1ß(IL-1ß) and tumor necrosis factor-α(TNF-α) in serum were detected by enzyme-linked immunosorbent assay(ELISA), and the mRNA and protein expression of α7nAChR-JAK2/STAT3 pathway core genes in spleen were detected by qRT-PCR, Western blot and immunohistochemistry. RESULTS:: showed that CM group(compared with HG group) and VA group(compared with CM group and SH group) had significantly decreased body weight(P<0.05, P<0.01), increased arthritis score(P<0.05, P<0.01), swollen ankle joints with deformity, and increased and enlarged lymph nodes in the spleen. There were also notable increases in the serum levels of IL-6, IL-1ß and TNF-α(P<0.05, P<0.01), and in the mRNA expressions of JAK2 and STAT3 in the spleen(P<0.05, P<0.01). The protein levels of phosphorylated JAK2(p-JAK2)/JAK2 and phospho-STAT3(p-STAT3)/STAT3 were significantly increased(P<0.05, P<0.01), and the number of JAK2, p-JAK2, STAT3 and p-STAT3 cells increased(P<0.05, P<0.01). EM group(compared with CM group) and ES group(compared with SH group) exhibited significantly increased body weight(P<0.01), decreased arthritis scores(P<0.05, P<0.01), reduced swelling of ankle joint, and decreased number and volume of lymph nodes in the spleen. Furthermore, serum levels of IL-6, IL-1ß, and TNF-α decreased(P<0.05, P<0.01), the mRNA expression of JAK2 and STAT3 in spleen decreased(P<0.05, P<0.01), the protein levels of p-JAK2/JAK2 and p-STAT3/STAT3 decreased(P<0.05, P<0.01), and the number of JAK2, p-JAK2, STAT3 and p-STAT3 cells decreased(P<0.05, P<0.01), whereas the mRNA and protein expressions of α7nAChR were significantly increased(P<0.01). Compared with the VA group, there was no significant differences in weight gain and arthritis scores in the EV group. The number of lymph nodes in the spleen was not significantly reduced and the volume was still large, suggesting the inflammation was not significantly improved. The serum levels of IL-6, IL-1ß and TNF-α were not significantly different, and there were no significant differences in α7nAChR, JAK2, and STAT3 mRNA expression in the spleen. The protein expression levels of p-JAK2/JAK2 and α7nAChR in spleen were lower(P<0.05, P<0.01), while p-STAT3/STAT3 protein expression was not significantly different. Besides, the two groups had no significant difference in the number of JAK2, p-JAK2, STAT3, and p-STAT3 cells. The results suggested that unilateral vagotomy promoted the increase of phosphorylated JAK2 and STAT3 expressions and exacerbated inflammation. In contrast, Ermiao Powder alleviated the inflammation in rheumatoid arthritis rats by activating the α7nAChR-mediated JAK2/STAT3 pathway through the vagus nerve, suggesting that the α7nAchR-JAK2/STAT3 pathway may be a potential target for the treatment of rheumatoid arthritis.


Assuntos
Artrite Experimental , Medicamentos de Ervas Chinesas , Janus Quinase 2 , Ratos Wistar , Fator de Transcrição STAT3 , Transdução de Sinais , Receptor Nicotínico de Acetilcolina alfa7 , Animais , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Janus Quinase 2/metabolismo , Janus Quinase 2/genética , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Ratos , Feminino , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Artrite Experimental/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Pós , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Humanos , Interleucina-6/genética
10.
J Org Chem ; 88(19): 13490-13503, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37748101

RESUMO

Proanthocyanidins (PACs) are complex flavan-3-ol polymers with stunning chemical complexity due to oxygenation patterns, oxidative phenolic ring linkages, and intricate stereochemistry of their heterocycles and inter-flavan linkages. Being promising candidates for dental restorative biomaterials, trace analysis of dentin bioactive cinnamon PACs now yielded novel trimeric (1 and 2) and tetrameric (3) PACs with unprecedented o- and p-benzoquinone motifs (benzoquinonoid PACs). Challenges in structural characterization, especially their absolute configuration, prompted the development of a new synthetic-analytical approach involving comprehensive spectroscopy, including NMR with quantum mechanics-driven 1H iterative functionalized spin analysis (HifSA) plus experimental and computational electronic circular dichroism (ECD). Vital stereochemical information was garnered from synthesizing 4-(2,5-benzoquinone)flavan-3-ols and a truncated analogue of trimer 2 as ECD models. Discovery of the first natural benzoquinonoid PACs provides new evidence to the experimentally elusive PAC biosynthesis as their formation requires two oxidative post-oligomerizational modifications (POMs) that are distinct and occur downstream from both quinone-methide-driven oligomerization and A-type linkage formation. While Nature is known to achieve structural diversity of many major compound classes by POMs, this is the first indication of PACs also following this common theme.


Assuntos
Proantocianidinas , Proantocianidinas/química , Fenóis , Espectroscopia de Ressonância Magnética , Dicroísmo Circular
11.
J Nat Prod ; 86(11): 2468-2473, 2023 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-37939268

RESUMO

Three unusual sesterterpenoids featuring unprecedented rearranged colquhounane (C25) and tetranorcolquhounane (C21) frameworks, colquhounoids E (1) and F (3) and norcolquhounoid F (2), were isolated from a Lamiaceae medicinal plant Colquhounia coccinea var. mollis. Their structures were elucidated by spectroscopic analysis and quantum chemical calculations. A biomimetic inspired regioselective cyclopropane cleavage was achieved under acidic conditions. The immunosuppressive activities of these new sesterterpenoids were also evaluated.


Assuntos
Lamiaceae , Plantas Medicinais , Análise Espectral , Lamiaceae/química , Estrutura Molecular
12.
13.
Dig Dis Sci ; 68(5): 1835-1846, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36459293

RESUMO

BACKGROUND/AIMS: Mesenchymal stem cells (MSCs) are a type of adult pluripotent stem cell that has anti-inflammatory and immunomodulatory effects, and whose conditioned medium (CM) has also been found to be effective. We used MSC and CM enemas to investigate their ameliorative effects in a mouse model of colitis. METHODS: We employed MSCs, CM, and MSCs + ML385 (an inhibitor of Nrf2) in dextran sodium sulfate (DSS)-induced colitis. Mice were sacrificed on day 8, and the effects of MSC or CM treatment on the levels of inflammation and oxidative stress in colonic epithelial cells were evaluated by histological analyses. RESULTS: MSCs inhibited inflammatory cell infiltration and proinflammatory cytokine expression in the colon. In addition, MSCs reduced extracellular matrix deposition and maintained the mechanical barrier and permeability of colonic epithelial cells. Mechanistically, MSCs activated Nrf2, which then increased HO-1 and NQO-1 levels and downregulated the expression of Keap1 to suppress reactive oxygen species production and MDA generation, accompanied by increases in components of the enzymatic antioxidant system, including SOD, CAT, GSH-Px, and T-AOC. However, after administering an Nrf2 inhibitor (ML385) to block the Nrf2/Keap1/ARE pathway, we failed to observe protective effects of MSCs in mice with colitis. CM alone also produced some of the therapeutic benefits of MSCs but was not as effective as MSCs. CONCLUSIONS: Our data confirmed that MSCs and CM can effectively improve intestinal mucosal repair in experimental colitis and that MSCs can improve this condition by activating the Nrf2/Keap1/ARE pathway.


Assuntos
Colite , Células-Tronco Mesenquimais , Camundongos , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Colite/induzido quimicamente , Colite/terapia , Colite/metabolismo , Transdução de Sinais , Células-Tronco Mesenquimais/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
14.
BMC Public Health ; 23(1): 2117, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891525

RESUMO

BACKGROUND: As the HIV epidemic among MSM in China continues, Chinese men who have sex with men (MSM) face various mental health difficulties, including suicide ideation, depression, and stigma. The current study aims to assess the mechanisms between HIV-related stigma, depression, and suicidal ideation among MSM in China. METHODS: This national cross-sectional study was completed on the geosocial networking application (GSN) app, Blued, from December 2020 to March 2021. We used the HIV Stigma Scale and the Center for Epidemiologic Studies Depression Scale (CES-D10) to measure HIV stigma and depression, respectively. Suicidal ideation was measured by the suicidal ideation-related item. Descriptive analyses, logistic regression, and structural equation modeling (SEM) were used for data analysis. RESULTS: A total of 244 HIV-positive MSM were included in the analysis. The mediation model revealed that the direct pathway of perceived HIV-related stigma on suicidal ideation was significant (standardized pathway coefficient = 0.07), and the indirect pathway of perceived HIV-related stigma on suicidal ideation via depression was also significant (standardized pathway coefficient = 0.04). There was a partial mediating effect of depression in the association between perceived HIV-related stigma and suicidal ideation. CONCLUSIONS: Our study found that both perceived HIV-related stigma and depression were associated with suicidal ideation among HIV-positive MSM in China, and that depression could serve as a mediator between HIV-related stigma and suicidal ideation. Targeted interventions regarding HIV-related stigma and depression should be taken into account to reduce suicidal ideation among HIV-positive MSM in China.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Ideação Suicida , Homossexualidade Masculina/psicologia , Depressão/epidemiologia , Depressão/psicologia , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Estudos Transversais , China/epidemiologia , Estigma Social
15.
Foodborne Pathog Dis ; 20(8): 351-357, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37471209

RESUMO

To conduct a study that examined the molecular epidemiology and pathogenesis of Salmonella Senftenberg isolates associated with an outbreak of foodborne disease in Guizhou Province and to provide a reference basis for the traceability of foodborne salmonellosis outbreaks and clinical diagnosis and treatment in the province. Fourteen strains of suspected Salmonella isolated from patient stool and food samples were used for pathogenic identification and serotyping by biochemical and mass spectrometry methods. Fourteen types of antibiotics were tested for drug sensitivity by the microbroth dilution method, and molecular typing was performed by pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). After the sequencing data were spliced by SPAdes, the gene protein sequences were compared with the Comprehensive Antibiotic Research Database and Virulence Factor Database, drug resistance and virulence genes were predicted, and whole genome multilocus sequence typing (wgMLST) was performed. The results were compared with those for Salmonella strains of the same serotype from the past 5 years in China detailed on the TraNet website. All 14 strains were identified as Salmonella Senftenberg (with the antigenic formula 1,3,19:g,s,t:-), and in the PFGE cluster tree, the strains were divided into two band types, with a similarity of 88.9%. The 14 strains were sensitive to the 14 antibiotics. WGS analysis showed that the 14 strains carried the same drug resistance and virulence genes and that all strains carried 3 aminoglycoside and lipopeptide drug resistance genes, including 114 virulence genes. The wgMLST results showed that the strains were distributed on the same small branch as those obtained from previous outbreaks of infection in Tianjin and Jilin. Salmonella Senftenberg, which caused the outbreak, carries a variety of virulence genes, which suggests that the strain is highly pathogenic. These pathogenic bacteria may be associated with the Salmonella strain in Tianjin, Jilin, and other places and have caused foodborne disease outbreaks as a result of imported contamination.


Assuntos
Doenças Transmitidas por Alimentos , Infecções por Salmonella , Humanos , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Infecções por Salmonella/microbiologia , Surtos de Doenças , Salmonella/genética , Antibacterianos/farmacologia , Eletroforese em Gel de Campo Pulsado
16.
J Pharmacol Exp Ther ; 383(1): 80-90, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36041883

RESUMO

Anwulignan (AN) is a monomer lignan from Schisandra sphenanthera Rehd. et Wits (Schisandra sphenanthera fructus, Schisandra sphenanthera). The protective effect of AN against the indomethacin (IND)-induced gastric injury to mice and the related mechanism of action was investigated in this study. The effect of AN was mainly assessed by observing the gastric tissue morphology, gastric ulcer index (GUI), ulcer inhibition rate (UIR), gastric juice volume (GJV) and pH value. Chemical colorimetry, immunofluorescence, ELISA, and Western blot were used to detect related factors in the gastric tissue. The results showed that AN reduced the GUI, increased the UIR, inhibited the GJV, and increased the gastric pH value. AN significantly increased cyclooxygenase-1, cyclooxygenase-2, and prostaglandin E2 expression levels in the gastric tissue, activated nuclear factor (erythroid-derived 2)-like 2 (Nrf2), increased heme oxygenase-1 expression, enhanced the activity of superoxide dismutase and glutathione peroxidase, and decreased the malondialdehyde content. AN reduced the phosphorylation of nuclear factor-κ gene binding (NF-κB) p65 and its nuclear translocation, the key protein of NF-κB signaling pathway in the gastric tissue, and the content of the pathway downstream signaling molecules, including interleukin-6, interleukin-1ß, and tumor necrosis factor-α, to play an anti-inflammatory role. AN inhibited the downstream signals B-cell lymphoma 2-associated x protein and cleaved caspase-3 in gastric tissue, and activated B-cell lymphoma 2, to play an antiapoptotic role, which were further verified by Hoechst staining. Therefore, AN has a significant protection against the gastric injury induced by IND in mice, and the mechanism may be concerned in its activation of Nrf2, inhibition of NF-κB signaling pathway, and anti-apoptotic effect. SIGNIFICANCE STATEMENT: Anwulignan (AN) significantly reduced the indomethacin-induced gastric injury in mice, and its antioxidation, anti-inflammation, and antiapoptosis were considered to be involve in the effect, suggesting that AN should be a potential drug or food supplement for gastric injury induced by indomethacin.


Assuntos
Lignanas , Fator 2 Relacionado a NF-E2 , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Caspase 3 , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Dinoprostona , Glutationa Peroxidase , Heme Oxigenase-1/metabolismo , Indometacina , Interleucina-1beta/genética , Interleucina-6 , Malondialdeído/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
17.
J Nat Prod ; 85(2): 391-404, 2022 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-35107279

RESUMO

To enable the further exploration of structure-activity relationships (SARs) of proanthocyanidins (PACs) with dentin biomodification abilities, Cinnamomum verum was selected for scaled-up purification of mixed A-/B-type, medium-size PAC oligomers. Sequential purification by centrifugal partition chromatography (CPC), Sephadex LH-20, and semiprep HPLC chromatography yielded four underivatized tetrameric (5-8) and two pentameric (9-10) PACs. Their unambiguous structural characterization involved extensive spectral and chemical degradation approaches to show that epicatechin units are connected by plant-specific combinations of doubly linked A- and singly linked B-type interflavanyl bonds. The biomechanical properties (via dynamic mechanical analysis) and physicochemical structure (via infrared spectroscopy) were assessed to evaluate the biomodification potency of PAC-treated collagen in a preclinical dentin model. This study revealed that (4→8) versus (4→6) bonds in PAC interflavan linkages have limited influence on biomechanical outcomes of dentin. By exhibiting a 25-fold increase in the complex modulus of treated dentin compared to control, aesculitannin E (5) was found to be the most potent PAC known to date for enhancing the mechanical properties of dentin in this preclinical model.


Assuntos
Catequina , Proantocianidinas , Catequina/análise , Cinnamomum zeylanicum/química , Dentina/química , Casca de Planta/química , Proantocianidinas/química
18.
J Nat Prod ; 85(12): 2753-2768, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36382951

RESUMO

Investigation of a pine bark extract for bioactive proanthocyanidin oligomers resulted in the isolation of structurally related dimeric seco B-type procyanidin derivatives, 1-5. This includes scalemic mixtures of gambiriin A1 (1a) and A2 (2a) and their newly described optical antipodes, ent-gambiriin A1 (1b) and ent-gambiriin A2 (2b), respectively, as well as a racemic mixture of the newly described (ent-)gambiriin A5 (3a/3b). Furthermore, the study now fully characterizes the previously reported optically pure dimers gambiriin B1 (4) and gambirflavan D1 (5), and characterized the novel seco B-type procyanidin trimer, 6 (gambirifuran C1). Thermal conversion of catechin in aqueous solution provided further evidence for the structures of 1-6 and led to the purification of semisynthetic 1a and 2a as well as additional dimers 7-10. Elucidating the structures of the natural dimers, 1-5, from comprehensive NMR and ECD data and synthetic evidence provided crucial reference points for establishing the structure of the seco B-type procyanidin trimer, 6. Serving as assigned building blocks, data from the dimers supported the 3D structural assignment of 6 based on NMR substituent chemical shift differences (s.c.s., syn. ΔδC) and component-based empirical ECD calculations. Within the newly characterized series of PAC-related molecules, 5 exhibited high dentin biomodification potential. In addition, considering the nomenclature issues and plausible biosynthetic pathways of this group of compounds led to a consolidated nomenclature of all currently known seco B-type procyanidins. These findings, thereby, expand the chemical space of bioactive catechin oligomers, which have promise as agents for the natural enhancement of dental biomaterials. Finally, the current knowledge of the chemical space of seco B-type procyanidin derivatives was compiled to the level of absolute configuration.


Assuntos
Biflavonoides , Catequina , Pinus , Proantocianidinas , Proantocianidinas/química , Catequina/química , Biflavonoides/química
19.
Appl Opt ; 61(36): 10688-10693, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36606927

RESUMO

Recently, visible light communication (VLC) has become a promising technology for reliable communication in the industrial Internet of Things. In VLC, light sources with non-uniform parameters make uncontrollable signal blind zones and aliases. The unknown parameters also lead to the problem of channel estimation. Hence, deep coverage of VLC is challenging. In this paper, we design a dual-sensor elongated receiver. The receiver expands the signal receiving area by increasing the distance between photon detectors and realizes aliased signal recovery without channel estimation. Cooperatively, an adaptive blind receiving scheme is proposed. The scheme separates aliased signals by parameter estimation of a Gaussian mixture model without knowing transmitter parameters. It unifies the aliased and blind receiving cases by an adaptive signal combining method. Finally, the simulation results demonstrate that our scheme achieves better reliability and deeper communication coverage in the given system.

20.
J Asian Nat Prod Res ; 24(6): 577-588, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34292106

RESUMO

Dimethyl itaconate (DMI) is an analog of dimethyl fumarate (DMF), an approved NF-E2-related Factor 2 (Nrf2) activator for multiple sclerosis. This study evaluated the potential of DMI as an anti-inflammatory agent by comparing DMI with DMF in electrophilicity, Nrf2 activation, and anti-inflammation in vitro. The results showed that DMI was less electrophilic but better at inducing a durable activation of Nrf2 when compared with DMF. However, DMI demonstrated poor anti-inflammatory effects in Jurkat cells, bone marrow-derived dendritic cells, and RAW264.7 cells. Our study suggested that DMI was a potent electrophilic Nrf2 activator but was probably not a promising anti-inflammatory agent.


Assuntos
Fumarato de Dimetilo , Fator 2 Relacionado a NF-E2 , Anti-Inflamatórios/farmacologia , Fumarato de Dimetilo/farmacologia , Fumarato de Dimetilo/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Estrutura Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Succinatos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA