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1.
Fitoterapia ; 177: 106056, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851515

RESUMO

Four new acylated oleanane-type triterpene saponins, symplosaponins A-D (1-4) were successfully isolated from the leaves of Symplocos cochinchinensis (Lour.) S. Moore, alongside with five known compounds (5-9), 2-methoxy-4-prop-1-enylphenyl-1-O-ß-D-apiofuranosyl-(1 â†’ 6)-ß-D-glucopyranoside (5), and 1-[O-ß-d-xylopyranosyl-(1 â†’ 6)-O-ß-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6), 6-O-p-coumaroylsucrose (7), arillatose B (8), and (-)-secoisolariciresinol-O-ß-D-glucopyranoside (9). The structures of these compounds were elucidated through spectroscopic methods, comparison with existing data, and chemical methods. Furthermore, all compounds were assessed for their impact on hepatocellular viability using the Resazurin reduction assay. These investigations aimed to explore the potential hepatoprotective properties of isolated compounds. As a result, 1-[O-ß-d-xylopyranosyl-(1 â†’ 6)-O-ß-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6) and (-)-secoisolariciresinol-O-ß-D-glucopyranoside (9) demonstrated statistically significant hepatoprotective activity in a concentration-dependent manner.

2.
Viruses ; 16(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38932134

RESUMO

OBJECTIVE: This study aims to evaluate the safety and immunogenicity of the SKYVaricella vaccine in healthy Vietnamese children aged 12 months to 12 years. METHODS: This open-label, single-arm study involved 201 children divided into two groups: 60 children aged 12 months to 5 years and 141 children aged 6 to 12 years. Safety was assessed through immediate reactions, solicited adverse events within 7 days, and unsolicited events up to Day 42. Immunogenicity was evaluated by seroconversion rates (SCR) and geometric mean titer (GMT) increments using fluorescent antibody-to-membrane antigen (FAMA) on the day of vaccination (D0) and 42 days after vaccination (D42). RESULTS: All participants completed the follow-up. Immediate adverse events included pain (8.0%), redness (8.0%), and swelling (20.9%) at the injection site. Within 7 days, pain (17.9%) and swelling (12.4%) were mild and self-resolving. Unsolicited adverse events were infrequent and mild. Both age groups achieved 100% SCR. GMT of varicella-zoster virus antibodies increased from 1.37 (SD 1.97) at D0 to 18.02 (SD 2.22) at D42, a 13.12-fold rise. No Grade 3 adverse events were observed. CONCLUSION: The SKYVaricella vaccine shows a robust immunogenic response and favorable safety profile in Vietnamese children aged 12 months to 12 years. These findings endorse its potential inclusion in pediatric vaccination programs as a reliable preventive option against varicella.


Assuntos
Anticorpos Antivirais , Vacina contra Varicela , Vacinas Atenuadas , Humanos , Masculino , Feminino , Vietnã , Criança , Vacina contra Varicela/imunologia , Vacina contra Varicela/efeitos adversos , Vacina contra Varicela/administração & dosagem , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Lactente , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/administração & dosagem , Pré-Escolar , Vacinação , Varicela/prevenção & controle , Varicela/imunologia , Imunogenicidade da Vacina , Herpesvirus Humano 3/imunologia , População do Sudeste Asiático
3.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869195

RESUMO

One new bithiophene derivative, 5-(but-3-en-1-yn-1-yl)-5'-(methoxymethyl)-2,2'-bithiophene (1), along with twelve known compounds, senecioester (2), tiglinsaureester (3), 5-acetoxymethyl-2'-(but-3-en-1-yn-1-yl)-2,5'-bithiophene (4), 5-(4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (5), 5-hydroxymethyl-(2,5':2',5'')-terthienyl tiglate (6), 5-hydroxymethyl-(2,5':2',5'')-terthienyl agelate (7), 5- hydroxymethyl-2,5':2',5''-terthiophene dimethylacrylate (8), 5-methoxymethyl-2,2':5',2''-terthiophene (9), α-terthiophene (10), 1,3,8,9-tetrahydroxycoumestan 3-sulfate (11), demethylwedelolactone (12), and wedelolactone (13) were isolated from the methanol extract of aerial parts of Eclipta prostrata (L.) L. All isolated compounds were evaluated for the protective ability on the HepG2 cells. At the concentration of 100 µM, compounds 11-13 showed the highest hepatoprotective effects, with HepG2 cell viability ranging from 38.68% to 48.54%. Bithiophenes showed higher hepatoprotective cell viability than terthiophenes.

4.
World Neurosurg ; 188: e128-e133, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38762026

RESUMO

OBJECTIVE: The purpose of this report is to describe a case series of children undergoing selective dorsal rhizotomy (SDR) for the treatment of spastic cerebral palsy in Vietnam. Also described is an international cooperation model to facilitate the development of a new, multidisciplinary team for the evaluation and treatment of these children. METHODS: Details of international collaboration are described, including in-person travel and virtual interactions. All cases of children younger than 18 years undergoing SDR for treatment of spastic cerebral palsy at a single center in Hanoi, Vietnam are described, including preoperative evaluation of spasticity and gait as well as results at 6 and 12 months. Results are summarized using descriptive statistics. RESULTS: Since the beginning of cooperation in training and transferring SDR techniques by experts from the United States, in the period from June 2016 to December 2022, 18 SDR surgeries were performed in Hanoi. Patients' ages ranged from 2 to 14 years; 13 were male and 5 were female. Overall, approximately 60% of nerve rootlets were cut. Modified Ashworth Scale scores at 6 and 12 months after surgery in the hip, knee, and ankle joints showed improvement from preoperative values. There were 2 recorded complications: intracranial hypotension causing subdural hemorrhage and a case of skin infection at the incision site. CONCLUSIONS: The ongoing international cooperation between Vietnamese and American physicians has helped improve the surgical treatment of spasticity in children with cerebral palsy in Hanoi, providing children with a surgical treatment option with successful outcomes.


Assuntos
Paralisia Cerebral , Rizotomia , Humanos , Rizotomia/métodos , Paralisia Cerebral/cirurgia , Paralisia Cerebral/complicações , Feminino , Masculino , Vietnã , Criança , Adolescente , Pré-Escolar , Resultado do Tratamento , Espasticidade Muscular/cirurgia
5.
Adv Mater ; 36(21): e2310351, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38591658

RESUMO

Obesity is a significant health concern that often leads to metabolic dysfunction and chronic diseases. This study introduces a novel approach to combat obesity using orally ingested self-powered electrostimulators. These electrostimulators consist of piezoelectric BaTiO3 (BTO) particles conjugated with capsaicin (Cap) and aim to activate the vagus nerve. Upon ingestion by diet-induced obese (DIO) mice, the BTO@Cap particles specifically target and bind to Cap-sensitive sensory nerve endings in the gastric mucosa. In response to stomach peristalsis, these particles generate electrical signals. The signals travel via the gut-brain axis, ultimately influencing the hypothalamus. By enhancing satiety signals in the brain, this neuromodulatory intervention reduces food intake, promotes energy metabolism, and demonstrates minimal toxicity. Over a 3-week period of daily treatments, DIO mice treated with BTO@Cap particles show a significant reduction in body weight compared to control mice, while maintaining their general locomotor activity. Furthermore, this BTO@Cap particle-based treatment mitigates various metabolic alterations associated with obesity. Importantly, this noninvasive and easy-to-administer intervention holds potential for addressing other intracerebral neurological diseases.


Assuntos
Doenças Metabólicas , Obesidade , Animais , Obesidade/metabolismo , Obesidade/terapia , Camundongos , Doenças Metabólicas/metabolismo , Doenças Metabólicas/terapia , Doenças Metabólicas/tratamento farmacológico , Eixo Encéfalo-Intestino , Titânio/química , Capsaicina/farmacologia , Capsaicina/administração & dosagem , Administração Oral , Terapia por Estimulação Elétrica/métodos , Camundongos Endogâmicos C57BL , Masculino , Compostos de Bário
6.
Vaccines (Basel) ; 11(10)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37896931

RESUMO

BACKGROUND: The effectiveness of the immunity provided by SARS-CoV-2 vaccines is an important public health issue. We analyzed the determinants of 12-month serology in a multicenter European cohort of vaccinated healthcare workers (HCW). METHODS: We analyzed the sociodemographic characteristics and levels of anti-SARS-CoV-2 spike antibodies (IgG) in a cohort of 16,101 vaccinated HCW from eleven centers in Germany, Italy, Romania, Slovakia and Spain. Considering the skewness of the distribution, the serological levels were transformed using log or cubic standardization and normalized by dividing them by center-specific standard errors. We fitted center-specific multivariate regression models to estimate the cohort-specific relative risks (RR) of an increase of one standard deviation of log or cubic antibody level and the corresponding 95% confidence interval (CI) for different factors and combined them in random-effects meta-analyses. RESULTS: We included 16,101 HCW in the analysis. A high antibody level was positively associated with age (RR = 1.04, 95% CI = 1.00-1.08 per 10-year increase), previous infection (RR = 1.78, 95% CI 1.29-2.45) and use of Spikevax [Moderna] with combinations compared to Comirnaty [BioNTech/Pfizer] (RR = 1.07, 95% CI 0.97-1.19) and was negatively associated with the time since last vaccine (RR = 0.94, 95% CI 0.91-0.98 per 30-day increase). CONCLUSIONS: These results provide insight about vaccine-induced immunity to SARS-CoV-2, an analysis of its determinants and quantification of the antibody decay trend with time since vaccination.

7.
Vaccines (Basel) ; 11(8)2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37631908

RESUMO

Understanding antibody persistence concerning multimorbidity is crucial for vaccination policies. Our goal is to assess the link between multimorbidity and serological response to SARS-CoV-2 nine months post-first vaccine. We analyzed Healthcare Workers (HCWs) from three cohorts from Italy, and one each from Germany, Romania, Slovakia, and Spain. Seven groups of chronic diseases were analyzed. We included 2941 HCWs (78.5% female, 73.4% ≥ 40 years old). Multimorbidity was present in 6.9% of HCWs. The prevalence of each chronic condition ranged between 1.9% (cancer) to 10.3% (allergies). Two regression models were fitted, one considering the chronic conditions groups and the other considering whether HCWs had diseases from ≥2 groups. Multimorbidity was present in 6.9% of HCWs, and higher 9-months post-vaccine anti-S levels were significantly associated with having received three doses of the vaccine (RR = 2.45, CI = 1.92-3.13) and with having a prior COVID-19 infection (RR = 2.30, CI = 2.15-2.46). Conversely, lower levels were associated with higher age (RR = 0.94, CI = 0.91-0.96), more time since the last vaccine dose (RR = 0.95, CI = 0.94-0.96), and multimorbidity (RR = 0.89, CI = 0.80-1.00). Hypertension is significantly associated with lower anti-S levels (RR = 0.87, CI = 0.80-0.95). The serological response to vaccines is more inadequate in individuals with multimorbidity.

8.
Biosci Rep ; 42(5)2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35502767

RESUMO

Brown adipose tissue (BAT) is a promising weapon to combat obesity and metabolic disease. BAT is thermogenic and consumes substantial amounts of glucose and fatty acids as fuel for thermogenesis and energy expenditure. To study BAT function in large human longitudinal cohorts, safe and precise detection methodologies are needed. Although regarded a gold standard, the foray of PET-CT into BAT research and clinical applications is limited by its high ionizing radiation doses. Here, we show that brown adipocytes release exosomes in blood plasma that can be utilized to assess BAT activity. In the present study, we investigated circulating protein biomarkers that can accurately and reliably reflect BAT activation triggered by cold exposure, capsinoids ingestion and thyroid hormone excess in humans. We discovered an exosomal protein, methylene tetrahydrofolate dehydrogenase (NADP+ dependent) 1-like (MTHFD1L), to be overexpressed and detectable in plasma for all three modes of BAT activation in human subjects. This mitochondrial protein is packaged as a cargo within multivesicular bodies of the endosomal compartment and secreted as exosomes via exocytosis from activated brown adipocytes into the circulation. To support MTHFD1L as a conserved BAT activation response in other vertebrates, we examined a rodent model and also proved its presence in blood of rats following BAT activation by cold exposure. Plasma concentration of exosomal MTHFD1L correlated with human BAT activity as confirmed by PET-MR in humans and supported by data from rats. Thus, we deduce that MTHFD1L appears to be overexpressed in activated BAT compared to BAT in the basal nonstimulated state.


Assuntos
Tecido Adiposo Marrom , Exossomos , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Animais , Metabolismo Energético , Exossomos/metabolismo , Humanos , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , NADP/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Ratos , Tetra-Hidrofolato Desidrogenase/metabolismo
9.
Appl Radiat Isot ; 163: 109229, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32561062

RESUMO

In this work, the physical dimensions and the actual position of germanium crystal within a detector housing, the homogeneity of the crystal surface and outer dead layer thickness for a p-type HPGe detector were confirmed by the scan method using the collimated low energy photon beams combined with Monte Carlo simulation. The length and the diameter of the crystal were found to match with the values supplied by the manufacturer in discrepancy of about 3%. Only one mounting strap (Typical) for holding the crystal inside the mounting cup instead of two which is indicated in the detector drawing supplied by manufacturer was revealed by scanning along the lateral face of detector. Scanning on the front surface and around the lateral face of detector by the collimated 59.5 keV photon beam verified the outer dead layer thicknesses at the front surface and lateral face of the crystal averagely increases about 6.5% and 12% respectively. Adjusting the detector parameters for MCNP simulation by these verified values, the simulated peak efficiencies for different photon energies become being in accordance with the experimental peak efficiencies.

10.
Protein Expr Purif ; 39(1): 97-106, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15596365

RESUMO

The mature lipase LipA and its 56aa-truncated chaperone DeltaLipBhis (with 6xhis-tag) from Ralstonia sp. M1 were over-expressed in Escherichia coli BL21 under the control of T7 promoter with a high level of 70 and 12mg protein per gram of wet cells, respectively. The simply purified lipase LipA was effectively refolded by Ni-NTA purified chaperone DeltaLipBhis in molar ratio 1:1 at 4 degrees C for 24 hours in H2O. The in vitro refolded lipase LipA had an optimal activity in the temperature range of 50-55 degrees C and was stable up to 45 degrees C with more than 84% activity retention. The maximal activity was observed at pH 10.75 for hydrolysis of olive oil and found to be stable over alkaline pH range 8.0-10.5 with more than 52% activity retention. The enzyme was found to be highly resistant to many organic solvents especially induced by ethanolamine (remaining activity 137-334%), but inhibited by 1-butanol and acetonitrile (40-86%). Metal ions Cu2+, Sn2+, Mn2+, Mg2+, and Ca2+ stimulated the lipase slightly with increase in activity by up to 22%, whereas Zn2+ significantly inhibited the enzyme with the residual activity of 30-65% and Fe3+ to a lesser degree (activity retention of 77-86%). Tween 80, Tween 60, and Tween 40 induced the activation of the lipase LipA (222-330%) and 0.2-1% (w/v) of Triton X-100, X-45, and SDS increased the lipase activity by up to 52%. However, 5% (w/v) of Triton X-100, X-45, and SDS inhibited strongly the activity by 31-89%. The inhibitors including DEPC, EDTA, PMSF, and 2-mercaptoethanol (0.1-10mM) inhibited moderately the lipase with remaining activity of 57-105%. The lipase LipA hydrolyzed a wide range of triglycerides, but preferentially short length acyl chains (C4 and C6). In contrast to the triglycerides, medium length acyl chains (C8 and C14) of p-nitrophenyl (p-NP) esters were preferential substrates of this lipase. The enzyme preferentially catalyzed the hydrolysis of cottonseed oil (317%), cornoil (227%), palm oil (222%), and wheatgerm oil (210%) in comparison to olive oil (100%).


Assuntos
Proteínas de Bactérias/genética , Chaperonas Moleculares/genética , Ralstonia/enzimologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/biossíntese , Clonagem Molecular , Detergentes , Estabilidade Enzimática , Vetores Genéticos , Concentração de Íons de Hidrogênio , Chaperonas Moleculares/biossíntese , Solventes , Especificidade por Substrato , Temperatura
11.
J Chromatogr A ; 962(1-2): 197-206, 2002 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-12198963

RESUMO

The determination of organotin compounds in water using gas chromatography-tandem mass spectrometry (GC-MS-MS) is described. Several organotin derivatives were synthesized by the reaction of organotin chlorides with Grignard reagents such as methyl-, propyl- and pentylmagnesium halides. After the optimization of the GC-MS-MS conditions, several derivatizations with the Grignard reagents were compared by evaluating the molar responses and volatilities of the derivatives and derivatization yields. As a result, the derivatizing reagent of choice is pentylmagnesium bromide. Calibration curves for the mono-, di- and tributyltins and mono-, di- and triphenyltins with pentylmagnesium bromide were linear in the range of 0.5-100 pg of Sn. The instrumental detection limits of six organotins ranged from 0.20 to 0.35 pg of Sn. The recovery tests from water samples (500 ml) were performed by using sodium diethyldithiocarbamate (DDTC) as a complexing reagent. Except for monophenyltin, the absolute recoveries of organotins from pure water at 200 ng of Sn/l were satisfactory. The recoveries calibrated by surrogate compounds (perdeuterated organotin chlorides) ranged from 71 to 109%. The method detection limits ranged from 0.26 to 0.84 pg of Sn (500-ml sample). This method was applied to the recovery of organotins from river water and seawater. The calibrated recoveries were between 90 and 122%.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Indicadores e Reagentes/química , Compostos Orgânicos de Estanho/análise , Poluentes Químicos da Água/análise , Calibragem , Padrões de Referência , Sensibilidade e Especificidade
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