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1.
Molecules ; 28(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37959661

RESUMO

Processing with heat treatment has been reported to alter several therapeutic effects of turmeric. In Vietnamese traditional medicine, turmeric has been long used for bacterial infections, and roasting techniques are sometimes applied with this material. However, there have been no studies investigating the effects of these thermal processes on the plant's antibacterial properties. Our study was therefore performed to examine the changes that roasting produced on this material. Slices of dried turmeric were further subjected to light-roasting (80 °C in 20 min) or dark-roasting (160 °C in 20 min) processes. Broth dilution and agar-well diffusion methods were applied to examine and compare the effects of ethanol extracts obtained from non-roasted, light-roasted and dark-roasted samples, on a set of 6 gram-positive and gram-negative bacteria. In both investigations, dark-roasted turmeric was significantly less antibacterial than non-roasted and light-roasted materials, as evident by the higher values of minimum inhibitory concentrations and the smaller diameters of induced inhibitory zones. In addition, dark-roasting was also found to clearly reduce curcumin contents, total polyphenol values and antioxidant activities of the extracts. These results suggest that non-roasting or light-roasting might be more suitable for the processing of turmeric materials that are aimed to be applied for bacterial infections.


Assuntos
Infecções Bacterianas , Curcuma , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Extratos Vegetais/farmacologia , Rizoma
2.
Plant Physiol Biochem ; 192: 72-86, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36208600

RESUMO

The effect of the endophytic Cupriavidus taiwanensis KKU2500-3 on the Cd toxicity of KDML105 rice seedlings was investigated in a 10 µM CdCl2 hydroponic system. As demonstrated after bacterial inoculation of germinating rice seeds, KKU2500-3 colonized all rice plant parts. In RB (Rice + KKU2500-3) and RBC (Rice + KKU2500-3+Cd), KKU2500-3 effectively colonized and was detected at a markedly higher number in the root surface and interior than in shoots and leaves. The activities of antioxidant enzymes ascorbate peroxidase (APOX), glutathione reductase (GR), and superoxide dismutase (SOD) and the proline content in inoculated rice were higher in roots and aboveground tissues. RBC exhibited a higher reduced-to-oxidized glutathione ratio in roots and leaves (3-55%) but a lower malondialdehyde content (8-78%). Phytochelatins (PCs) were detected in all rice tissues, but their levels in RBC were 13-70% lower than those in RC (Rice + Cd), demonstrating that the induction of PCs in rice was unrelated to KKU2500-3. The Cd levels in roots and shoots were lower in RBC than RC, and the root-to-shoot Cd translocation factor was 0.6-62.2% lower. At 30 DAT, the Cd levels in RBC roots and shoots were 30.2% and 73.7% lower, respectively, than those in RC. Colonized KKU2500-3 activated GR and increased the proline content to overcome rice Cd toxicity. These effects may trap Cd in plant cells and reduce its translocation. Hence, KKU2500-3 synergistically interacts with rice to detoxify Cd at early growth stages, and KDML105 rice grains with low Cd accumulation could be produced if this interaction is maintained until late growth stages.

3.
Biomedicines ; 10(10)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36289803

RESUMO

People who inject drugs (PWID) are a population exposed to many genotoxicants and with a high prevalence of HCV infection. Direct-acting antiviral (DAA) regimens are now widely used to treat chronic HCV infection. Although side effects to treatment are currently rare, the long-term effects such as suspicions of de novo hepatocellular carcinoma (HCC) occurrence or HCC recurrence and cardiac defects are still up for debate. Given the structure of DAAs, the molecules have a potential mitochondrial DNA (mtDNA) genotoxicity. We have previously reported acute mtDNA toxicity of three DAA regimens among PWID with a strong impact on the rate of mtDNA deletion, less on the quantity of mtDNA copy per cell at sustained viral response at 12 weeks (SVR12). Herein, we report the mtDNA parameters nine months after drug discontinuation. We observed that the percentage of the deleted mtDNA genome increased over time. No exposure to any other genotoxicants during this period was associated with a high deletion percentage, suggesting that the replicative advantage of the deleted molecules outweighed their elimination processes. Such observation calls for longer-term follow-up and may contribute to the molecular basis of subclinical side effects of DAA treatments.

4.
Am J Hum Genet ; 105(6): 1294-1301, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31761294

RESUMO

The development of hindlimbs in tetrapod species relies specifically on the transcription factor TBX4. In humans, heterozygous loss-of-function TBX4 mutations cause dominant small patella syndrome (SPS) due to haploinsufficiency. Here, we characterize a striking clinical entity in four fetuses with complete posterior amelia with pelvis and pulmonary hypoplasia (PAPPA). Through exome sequencing, we find that PAPPA syndrome is caused by homozygous TBX4 inactivating mutations during embryogenesis in humans. In two consanguineous couples, we uncover distinct germline TBX4 coding mutations, p.Tyr113∗ and p.Tyr127Asn, that segregated with SPS in heterozygous parents and with posterior amelia with pelvis and pulmonary hypoplasia syndrome (PAPPAS) in one available homozygous fetus. A complete absence of TBX4 transcripts in this proband with biallelic p.Tyr113∗ stop-gain mutations revealed nonsense-mediated decay of the endogenous mRNA. CRISPR/Cas9-mediated TBX4 deletion in Xenopus embryos confirmed its restricted role during leg development. We conclude that SPS and PAPPAS are allelic diseases of TBX4 deficiency and that TBX4 is an essential transcription factor for organogenesis of the lungs, pelvis, and hindlimbs in humans.


Assuntos
Anormalidades Múltiplas/etiologia , Doenças do Desenvolvimento Ósseo/etiologia , Ectromelia/etiologia , Quadril/anormalidades , Homozigoto , Ísquio/anormalidades , Mutação com Perda de Função , Pneumopatias/etiologia , Pulmão/anormalidades , Patela/anormalidades , Pelve/anormalidades , Proteínas com Domínio T/genética , Anormalidades Múltiplas/patologia , Adolescente , Doenças do Desenvolvimento Ósseo/patologia , Criança , Ectromelia/patologia , Feminino , Quadril/patologia , Humanos , Ísquio/patologia , Pulmão/patologia , Pneumopatias/patologia , Masculino , Patela/patologia , Linhagem , Pelve/patologia , Prognóstico
5.
Cell Rep ; 28(13): 3338-3352.e6, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31553905

RESUMO

Mucociliary epithelia provide a first line of defense against pathogens. Impaired regeneration and remodeling of mucociliary epithelia are associated with dysregulated Wnt/ß-catenin signaling in chronic airway diseases, but underlying mechanisms remain elusive, and studies yield seemingly contradicting results. Employing the Xenopus mucociliary epidermis, the mouse airway, and human airway Basal cells, we characterize the evolutionarily conserved roles of Wnt/ß-catenin signaling in vertebrates. In multiciliated cells, Wnt is required for cilia formation during differentiation. In Basal cells, Wnt prevents specification of epithelial cell types by activating ΔN-TP63, a master transcription factor, which is necessary and sufficient to mediate the Wnt-induced inhibition of specification and is required to retain Basal cells during development. Chronic Wnt activation leads to remodeling and Basal cell hyperplasia, which are reversible in vivo and in vitro, suggesting Wnt inhibition as a treatment option in chronic lung diseases. Our work provides important insights into mucociliary signaling, development, and disease.


Assuntos
Epitélio/metabolismo , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Via de Sinalização Wnt/imunologia , beta Catenina/metabolismo , Animais , Diferenciação Celular , Humanos , Camundongos
6.
BMC Med Res Methodol ; 18(1): 43, 2018 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-29776431

RESUMO

BACKGROUND: Information on causes of death (COD) is crucial for measuring the health outcomes of populations and progress towards the Sustainable Development Goals. In many countries such as Vietnam where the civil registration and vital statistics (CRVS) system is dysfunctional, information on vital events will continue to rely on verbal autopsy (VA) methods. This study assesses the validity of VA methods used in Vietnam, and provides recommendations on methods for implementing VA validation studies in Vietnam. METHODS: This validation study was conducted on a sample of 670 deaths from a recent VA study in Quang Ninh province. The study covered 116 cases from this sample, which met three inclusion criteria: a) the death occurred within 30 days of discharge after last hospitalisation, and b) medical records (MRs) for the deceased were available from respective hospitals, and c) the medical record mentioned that the patient was terminally ill at discharge. For each death, the underlying cause of death (UCOD) identified from MRs was compared to the UCOD from VA. The validity of VA diagnoses for major causes of death was measured using sensitivity, specificity and positive predictive value (PPV). RESULTS: The sensitivity of VA was at least 75% in identifying some leading CODs such as stroke, road traffic accidents and several site-specific cancers. However, sensitivity was less than 50% for other important causes including ischemic heart disease, chronic obstructive pulmonary diseases, and diabetes. Overall, there was 57% agreement between UCOD from VA and MR, which increased to 76% when multiple causes from VA were compared to UCOD from MR. CONCLUSIONS: Our findings suggest that VA is a valid method to ascertain UCOD in contexts such as Vietnam. Furthermore, within cultural contexts in which patients prefer to die at home instead of a healthcare facility, using the available MRs as the gold standard may be meaningful to the extent that recall bias from the interval between last hospital discharge and death can be minimized. Therefore, future studies should evaluate validity of MRs as a gold standard for VA studies in contexts similar to the Vietnamese context.


Assuntos
Autopsia/métodos , Causas de Morte , Registros Hospitalares/estatística & dados numéricos , Prontuários Médicos/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários , Vietnã
7.
J Cell Sci ; 130(14): 2371-2381, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28576973

RESUMO

Caspases constitute a family of cysteine proteases centrally involved in programmed cell death, which is an integral part of normal embryonic and fetal development. However, it has become clear that specific caspases also have functions independent of cell death. In order to identify novel apoptotic and nonapoptotic developmental caspase functions, we designed and transgenically integrated novel fluorescent caspase reporter constructs in developing Xenopus embryos and tadpoles. This model organism has an external development, allowing direct and continuous monitoring. These studies uncovered a nonapoptotic role for the initiator caspase-9 in primitive blood formation. Functional experiments further corroborated that caspase-9, but possibly not the executioners caspase-3 and caspase-7, are required for primitive erythropoiesis in the early embryo. These data reveal a novel nonapoptotic function for the initiator caspase-9 and, for the first time, implicate nonapoptotic caspase activity in primitive blood formation.


Assuntos
Caspase 9/metabolismo , Xenopus laevis/sangue , Animais , Apoptose/fisiologia , Morte Celular/fisiologia , Diferenciação Celular/fisiologia , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Células HEK293 , Humanos , Transdução de Sinais , Transfecção , Xenopus laevis/embriologia
8.
Oncoscience ; 2(5): 555-66, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26097888

RESUMO

Truncating mutations in the tumor suppressor gene adenomatous polyposis coli (APC) are the initiating step in the vast majority of sporadic colorectal cancers, and they underlie familial adenomatous polyposis (FAP) syndromes. Modeling of APC- driven tumor formation in the mouse has contributed substantially to our mechanistic understanding of the associated disease, but additional models are needed to explore therapeutic opportunities and overcome current limitations of mouse models. We report on a novel and penetrant genetic cancer model in Xenopus tropicalis, an aquatic tetrapod vertebrate with external development, diploid genome and short life cycle. Tadpoles and froglets derived from embryos injected with TAL effector nucleases targeting the apc gene rapidly developed intestinal hyperplasia and other neoplasms observed in FAP patients, including desmoid tumors and medulloblastomas. Bi-allelic apc mutations causing frame shifts were detected in the tumors, which displayed activation of the Wnt/ß-catenin pathway and showed increased cellular proliferation. We further demonstrate that simultaneous double bi-allelic mutation of apc and a non-relevant gene is possible in the neoplasias, opening the door for identification and characterization of effector or modifier genes in tumors expressing truncated apc. Our results demonstrate the power of modeling human cancer in Xenopus tropicalis using mosaic TALEN-mediated bi-allelic gene disruption.

9.
Proc Natl Acad Sci U S A ; 107(37): 16160-5, 2010 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-20805504

RESUMO

The formation of primitive (embryonic) blood in vertebrates is mediated by spatio-temporally restricted signaling between different tissue layers. In Xenopus, in which primitive blood originates in the ventral blood island, this involves the secretion of bone morphogenetic protein (BMP) ligands by the ectoderm that signal to the underlying mesoderm during gastrulation. Using novel transgenic reporter lines, we report that the canonical Wnt/ß-catenin pathway is also activated in the blood islands in Xenopus. Furthermore, Wnt-reporter activity was also detected in the blood islands of the mouse yolk sac. By using morpholino-mediated depletion in Xenopus, we identified Wnt4 as the ligand that is expressed in the mesoderm of the ventral blood island and is essential for the expression of hematopoietic and erythroid marker genes. Injection of an inducible Wnt-interfering construct further showed that, during gastrulation, Wnt/ß-catenin signaling is required both in the mesoderm and in the overlying ectoderm for the formation of the ventral blood island. Using recombination assays with embryonic explants, we document that ectodermal BMP4 expression is dependent on Wnt4 signals from the mesoderm. Our results thus reveal a unique role for Wnt4-mediated canonical signaling in the formation and maintenance of the ventral blood island in Xenopus.


Assuntos
Hematopoese , Transdução de Sinais , Proteínas Wnt/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriologia , Xenopus laevis/metabolismo , beta Catenina/metabolismo , Animais , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Wnt/genética , Proteína Wnt4 , Proteínas de Xenopus/genética , Xenopus laevis/genética
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