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1.
Proc Natl Acad Sci U S A ; 119(50): e2217542119, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36490315

RESUMO

R-loops, or RNA:DNA hybrids, can induce DNA damage, which requires DNA repair factors including breast cancer type 1 susceptibility protein (BRCA1) to restore genomic integrity. To date, several pathogenic mutations have been found within the tandem BRCA1 carboxyl-terminal (BRCT) domains that mediate BRCA1 interactions with proteins and DNA in response to DNA damage. Here, we describe a nonrepair role of BRCA1 BRCT in suppressing ribosomal R-loops via two mechanisms. Through its RNA binding and annealing activities, BRCA1 BRCT facilitates the formation of double-stranded RNA between ribosomal RNA (rRNA) and antisense-rRNA (as-rRNA), hereby minimizing rRNA hybridization to ribosomal DNA to form R-loops. BRCA1 BRCT also promotes RNA polymerase I-dependent transcription of as-rRNA to enhance double-stranded rRNA (ds-rRNA) formation. In addition, BRCA1 BRCT-mediated as-rRNA production restricts rRNA maturation in unperturbed cells. Hence, impairing as-rRNA transcription and ds-rRNA formation due to BRCA1 BRCT deficiency deregulates rRNA processing and increases ribosomal R-loops and DNA breaks. Our results link ribosomal biogenesis dysfunction to BRCA1-associated genomic instability.


Assuntos
Proteína BRCA1 , RNA de Cadeia Dupla , Proteína BRCA1/metabolismo , RNA Antissenso , Reparo do DNA , Dano ao DNA , DNA
2.
AIDS Care ; 36(5): 631-640, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37339000

RESUMO

The Human Immunodeficiency Virus (HIV) epidemic remains a major public health issue worldwide. In Vietnam, the HIV epidemic is essentially driven by people who inject drugs (PWID). This study aims to compare mortality and loss to follow-up (LTFU) between PWID and other patients. From June 2017 to April 2018, HIV-infected adults were enrolled in a prospective cohort from time of ART initiation in six provinces of North Vietnam. The end date was July 2020. Mortality and LTFU were described using competing-risk survival models. Factors associated with mortality and with LTFU were identified using Cox models with a competing-risk approach. Of the 578 participants, 261 (45.2%) were PWID and almost exclusively male. 49 patients died, corresponding to a mortality rate (95% confidence interval (CI)) of 3.7 (2.8-4.9) per 100 person-months, and 79 were lost to follow-up, corresponding to a rate (95% CI) of 6.0 (4.8-7.4) per 100 person-months. PWID were at higher risk of death but not of LTFU. Overall, LTFU was high in both groups. Latecomers to clinical visits were more at risk of both death and LTFU. Therefore, this should be a warning to clinical teams and preventive actions taken in these patients.Trial registration: ClinicalTrials.gov identifier: NCT03249493..


Assuntos
Infecções por HIV , Abuso de Substâncias por Via Intravenosa , Adulto , Humanos , Masculino , HIV , Infecções por HIV/epidemiologia , Incidência , Perda de Seguimento , Estudos Prospectivos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Vietnã/epidemiologia , Feminino
3.
Phytochem Anal ; 35(3): 521-529, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38198752

RESUMO

INTRODUCTION: Sennosides are the main active constituents of the dried leaves and/or pods of Senna alexandrina Mill. that are used as laxatives. A hypothesis is that aglycones are formed during the degradation of sennosides. However, it is unknown, whether this happens under visible light exposure and how photosensitive sennosides behave in solution. OBJECTIVES: Pure anthraquinone glycosides were tested on their behaviour during sample preparation in the lab under visible light exposure in dependence on the instability of the solvent. MATERIALS AND METHODS: Samples before and after exposure were analysed using UHPLC with UV/Vis and MS detection. RESULTS: Under visible light protection, the solutions were stable for 14 days at room temperature whereas a loss of 20%-60% was measured after 1 day of light exposure. The loss of sennosides due to degradation can be as fast as up to 2%-2.5% per hour, which might have a tremendous impact on phytochemical analysis results during the course of an analysis. The formation of aglycones was not observed in the degradation of sennosides and rhein-8-O-glucoside. CONCLUSION: Aglycones could not be found as a result of the forced degradation. The solutions of sennosides clearly need to be protected from light to obtain reliable analytical results, and light protection is a major point for the stability of liquid preparations.


Assuntos
Extrato de Senna , Senna , Senosídeos , Extrato de Senna/análise , Antraquinonas , Senna/metabolismo , Glucosídeos , Folhas de Planta/química
4.
Biotechnol Lett ; 45(5-6): 689-702, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37071381

RESUMO

OBJECTIVES: This work aimed to construct a versatile, effective, and food-grade Agrobacterium tumefaciens-mediated transformation (ATMT) system for recombinant expression in the filamentous fungus Penicillium rubens (also known as Pencillium chrysogenum). RESULTS: In this study, the wild-type P. chrysogenum VTCC 31172 strain was re-classified as P. rubens by a multilocus sequencing analysis. Further, the pyrG gene required for uridine/uracil biosynthesis was successfully deleted in the VTCC 31172 strain by homologous recombination to generate a stable uridine/uracil auxotrophic mutant (ΔpyrG). The growth of the P. rubens ΔpyrG strain could be restored by uridine/uracil supplementation, and a new ATMT system based on the uridine/uracil auxotrophic mechanism was established for this strain. The optimal ATMT efficiency could reach 1750 transformants for 106 spores (equivalent to 0.18%). In addition, supplementation of uridine/uracil at the concentrations of 0.005-0.02% during the co-cultivation process significantly promoted transformation efficiency. Especially, we demonstrated that the pyrG marker and the amyB promoter from the koji mold Aspergillus oryzae were fully functional in P. rubens ΔpyrG. Expression of the DsRed reporter gene under the regulation of the A. oryzae amyB promoter lighted up the mycelium of P. rubens with a robust red signal under fluorescence microscopy. Furthermore, genomic integration of multiple copies of the Aspergillus fumigatus phyA gene under the control of the amyB promoter significantly enhanced phytase activity in P. rubens. CONCLUSIONS: The ATMT system developed in our work provides a safe genetic platform for producing recombinant products in P. rubens without using drug resistance markers.


Assuntos
Penicillium , Penicillium/genética , Penicillium/metabolismo , Agrobacterium tumefaciens/genética , Uracila/metabolismo , Uridina , Transformação Genética
5.
Clin Infect Dis ; 75(Suppl 2): S174-S181, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-35723271

RESUMO

BACKGROUND: Before the SARS-CoV-2 Delta variant arrived in Vietnam, case rates suggested seroprevalence of SARS-CoV-2 was low. Beginning in March 2021, we assessed different dosing schedules and adverse events following immunization (AEFIs) for ChAdOx1 nCoV-19 vaccine among healthcare workers (HCWs). METHODS: We performed a prospective cohort study to estimate the prevalence of IgG antibodies to SARS-CoV-2 before and after ChAdOx1 nCoV-19 vaccination. We conducted antibody testing among HCWs in February 2021 (baseline), before the second dose (June-July 2021), and 1 and 3 months after the second dose. We detected antibodies to SARS-CoV-2 using Tetracore® FlexImmArray™, and surrogate neutralizing antibodies using GenScript cPass™. Neither assay can distinguish natural from vaccine-induced antibodies. We assessed AEFIs through interview post-dose 1 and 1 month post-dose 2. RESULTS: Before vaccination, 1/617 participants (0.16%) had antibodies to SARS-CoV-2. Of these 617, 405 were vaccinated with ChAdOx1 nCoV-19 with 4-8- (60%), 9-12- (27%), or ≥13-week (13%) intervals between the 2 doses. Three months following series completion, 99% and 97% of vaccinated participants had ≥1 sample with detectable antibodies and surrogate neutralizing antibodies against SARS-CoV-2, respectively. We observed no significant differences among those with different dosing intervals at last follow-up. All participants reported PCR testing for SARS-CoV-2 during the study; 2 (0.5%) were laboratory-confirmed. AEFIs were more frequent post-dose 1 (81%) vs post-dose 2 (21%). CONCLUSIONS: In this population, regardless of dosing interval, ChAdOx1 nCoV-19 induced antibodies within 3 months of the second dose. These findings may offer flexibility to policymakers when balancing programmatic considerations with vaccine effectiveness.


Assuntos
COVID-19 , Vacinas Virais , Anticorpos Neutralizantes , Anticorpos Antivirais , Povo Asiático , COVID-19/epidemiologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , Pessoal de Saúde , Humanos , Imunoglobulina G , Estudos Prospectivos , SARS-CoV-2 , Estudos Soroepidemiológicos , Vacinação , Vietnã/epidemiologia
6.
J Neuroophthalmol ; 41(4): e759-e760, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33449492

RESUMO

ABSTRACT: A 25-year-old male patient visited the ophthalmology clinic because of upper eye lid ptosis in the right eye, binocular double vision, and light sensitivity. He was diagnosed with a complete third nerve palsy caused by a skull base myofibroma, a rare clinical entity that has not been described before in oculomotor nerve palsy.


Assuntos
Miofibroma , Doenças do Nervo Oculomotor , Adulto , Humanos , Masculino , Miofibroma/complicações , Nervo Oculomotor , Doenças do Nervo Oculomotor/diagnóstico , Doenças do Nervo Oculomotor/etiologia , Base do Crânio
7.
Proc Natl Acad Sci U S A ; 115(2): E162-E171, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29279395

RESUMO

Coronaviruses (CoVs) stand out among RNA viruses because of their unusually large genomes (∼30 kb) associated with low mutation rates. CoVs code for nsp14, a bifunctional enzyme carrying RNA cap guanine N7-methyltransferase (MTase) and 3'-5' exoribonuclease (ExoN) activities. ExoN excises nucleotide mismatches at the RNA 3'-end in vitro, and its inactivation in vivo jeopardizes viral genetic stability. Here, we demonstrate for severe acute respiratory syndrome (SARS)-CoV an RNA synthesis and proofreading pathway through association of nsp14 with the low-fidelity nsp12 viral RNA polymerase. Through this pathway, the antiviral compound ribavirin 5'-monophosphate is significantly incorporated but also readily excised from RNA, which may explain its limited efficacy in vivo. The crystal structure at 3.38 Šresolution of SARS-CoV nsp14 in complex with its cofactor nsp10 adds to the uniqueness of CoVs among RNA viruses: The MTase domain presents a new fold that differs sharply from the canonical Rossmann fold.


Assuntos
Coronavirus/metabolismo , RNA Viral/metabolismo , Ribavirina/metabolismo , Replicação Viral , Antivirais/metabolismo , Antivirais/farmacologia , Coronavirus/efeitos dos fármacos , Coronavirus/genética , Cristalografia por Raios X , Exorribonucleases/química , Exorribonucleases/genética , Exorribonucleases/metabolismo , Humanos , Metiltransferases/química , Metiltransferases/genética , Metiltransferases/metabolismo , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , RNA Viral/genética , Ribavirina/farmacologia , Síndrome Respiratória Aguda Grave/virologia , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo
8.
Proc Natl Acad Sci U S A ; 113(26): 7177-82, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27298340

RESUMO

Foreign DNA molecules and chromosomal fragments are generally eliminated from proliferating cells, but we know little about how mammalian cells prevent their propagation. Here, we show that dividing human and canine cells partition transfected plasmid DNA asymmetrically, preferentially into the daughter cell harboring the young centrosome. Independently of how they entered the cell, most plasmids clustered in the cytoplasm. Unlike polystyrene beads of similar size, these clusters remained relatively immobile and physically associated to endoplasmic reticulum-derived membranes, as revealed by live cell and electron microscopy imaging. At entry of mitosis, most clusters localized near the centrosomes. As the two centrosomes split to assemble the bipolar spindle, predominantly the old centrosome migrated away, biasing the partition of the plasmid cluster toward the young centrosome. Down-regulation of the centrosomal proteins Ninein and adenomatous polyposis coli abolished this bias. Thus, we suggest that DNA clustering, cluster immobilization through association to the endoplasmic reticulum membrane, initial proximity between the cluster and centrosomes, and subsequent differential behavior of the two centrosomes together bias the partition of plasmid DNA during mitosis. This process leads to their progressive elimination from the proliferating population and might apply to any kind of foreign DNA molecule in mammalian cells. Furthermore, the functional difference of the centrosomes might also promote the asymmetric partitioning of other cellular components in other mammalian and possibly stem cells.


Assuntos
DNA/metabolismo , Retículo Endoplasmático/metabolismo , Animais , Divisão Celular , Centrossomo/metabolismo , Proteínas do Citoesqueleto/genética , Cães , Células HeLa , Humanos , Células Madin Darby de Rim Canino , Mitose , Proteínas Nucleares/genética , Plasmídeos , Transfecção
9.
Addict Biol ; 20(3): 617-27, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24832863

RESUMO

Alcohol and drug use disorders are individually heritable (50%). Twin studies indicate that alcohol and substance use disorders share common genetic influences, and therefore may represent a more heritable form of addiction and thus be more powerful for genetic studies. This study utilized data from 2322 subjects from 118 European-American families in the Collaborative Study on the Genetics of Alcoholism sample to conduct genome-wide association analysis of a binary and a continuous index of general substance dependence liability. The binary phenotype (ANYDEP) was based on meeting lifetime criteria for any DSM-IV dependence on alcohol, cannabis, cocaine or opioids. The quantitative trait (QUANTDEP) was constructed from factor analysis based on endorsement across the seven DSM-IV criteria for each of the four substances. Heritability was estimated to be 54% for ANYDEP and 86% for QUANTDEP. One single-nucleotide polymorphism (SNP), rs2952621 in the uncharacterized gene LOC151121 on chromosome 2, was associated with ANYDEP (P = 1.8 × 10(-8) ), with support from surrounding imputed SNPs and replication in an independent sample [Study of Addiction: Genetics and Environment (SAGE); P = 0.02]. One SNP, rs2567261 in ARHGAP28 (Rho GTPase-activating protein 28), was associated with QUANTDEP (P = 3.8 × 10(-8) ), and supported by imputed SNPs in the region, but did not replicate in an independent sample (SAGE; P = 0.29). The results of this study provide evidence that there are common variants that contribute to the risk for a general liability to substance dependence.


Assuntos
Proteínas Ativadoras de GTPase/genética , Polimorfismo de Nucleotídeo Único/genética , Transtornos Relacionados ao Uso de Substâncias/genética , Adolescente , Feminino , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Fenótipo , Adulto Jovem
10.
J Clin Microbiol ; 52(5): 1366-74, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24523471

RESUMO

Norovirus and rotavirus are the two most important causes of acute gastroenteritis in children worldwide. Both norovirus and rotavirus recognize human histo-blood group antigens (HBGAs), and multiple binding patterns for HBGAs have been reported. To explore the role of HBGAs in host susceptibility to norovirus and rotavirus, we conducted a cross-sectional study in children hospitalized with diarrhea in northern Vietnam from September 2010 through September 2012. Of 260 children with paired stool and saliva samples, 158 (61%) were classified as HBGA secretors (Lea-b+), 31 (12%) were nonsecretors (Lea+b-), and 71 (27%) were partial secretors (Lea+b+). Norovirus was detected in 50 patients (19%), with viral genotypes GII.3 (n=28) and GII.4 (n=22) being the most common. All children infected with norovirus strains of genotype GII.4 were either HBGA secretors or partial secretors. Of the 28 GII.3 cases, 12 involved HBGA secretors, 11 partial secretors, and 5 nonsecretors. A total of 85 children tested positive for rotavirus, 74 of whom were infected with genotype P[8], 5 with P[4], and 6 with P[6]; all were HBGA secretors or partial secretors. This is the first epidemiological study demonstrating in a population that HBGA phenotype is a key susceptibility factor for both norovirus and rotavirus infections in children.


Assuntos
Antígenos de Grupos Sanguíneos/imunologia , Infecções por Caliciviridae/imunologia , Suscetibilidade a Doenças/imunologia , Norovirus/imunologia , Infecções por Rotavirus/imunologia , Rotavirus/imunologia , Infecções por Caliciviridae/virologia , Pré-Escolar , Estudos Transversais , Suscetibilidade a Doenças/virologia , Fezes/virologia , Gastroenterite/imunologia , Gastroenterite/virologia , Genótipo , Humanos , Lactente , Norovirus/genética , Fenótipo , Rotavirus/genética , Infecções por Rotavirus/virologia , Saliva/imunologia , Saliva/virologia , Vietnã
11.
Alcohol Clin Exp Res ; 38(2): 354-66, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24015780

RESUMO

BACKGROUND: Despite the high heritability of alcohol dependence (AD), the genes found to be associated with it account for only a small proportion of its total variability. The goal of this study was to identify and analyze phenotypes based on homogeneous classes of individuals to increase the power to detect genetic risk factors contributing to the risk of AD. METHODS: The 7 individual DSM-IV criteria for AD were analyzed using latent class analysis (LCA) to identify classes defined by the pattern of endorsement of the criteria. A genome-wide association study was performed in 118 extended European American families (n = 2,322 individuals) densely affected with AD to identify genes associated with AD, with each of the 7 DSM-IV criteria, and with the probability of belonging to 2 of 3 latent classes. RESULTS: Heritability for DSM-IV AD was 61% and ranged from 17 to 60% for the other phenotypes. A single nucleotide polymorphism (SNP) in the olfactory receptor OR51L1 was significantly associated (7.3 × 10(-8) ) with the DSM-IV criterion of persistent desire to, or inability to, cut down on drinking. LCA revealed a 3-class model: the "low-risk" class (50%) rarely endorsed any criteria and none met criteria for AD; the "moderate-risk" class (33%) endorsed primarily 4 DSM-IV criteria and 48% met criteria for AD; and the "high-risk" class (17%) manifested high endorsement probabilities for most criteria and nearly all (99%) met criteria for AD. One SNP in a sodium leak channel NALCN demonstrated genome-wide significance with the high-risk class (p = 4.1 × 10(-8) ). Analyses in an independent sample did not replicate these associations. CONCLUSIONS: We explored the genetic contribution to several phenotypes derived from the DSM-IV AD criteria. The strongest evidence of association was with SNPs in NALCN and OR51L1.


Assuntos
Alcoolismo/genética , Alcoolismo/psicologia , Família , Adulto , Consumo de Bebidas Alcoólicas/genética , Consumo de Bebidas Alcoólicas/psicologia , Comitês de Monitoramento de Dados de Ensaios Clínicos , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Canais Iônicos , Desequilíbrio de Ligação , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Canais de Sódio/genética , Estados Unidos , População Branca
12.
Front Psychol ; 15: 1372405, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770251

RESUMO

Introduction: Mayer-Rokitansky-Küster-Hauser syndrome (MRKH) is rare condition that has a negative impact on quality of life because affected women lack a uterus and vagina, and are therefore unable to engage in sexual intercourse and experience natural pregnancy. This study evaluated perceptions of surrogacy in Vietnamese women with MRKH who have started families. Method: Women with MRKH who had undergone successful vaginal reconstruction, were married, and had started families participated in a semi-structured, in-depth, one-on-one online video interview with an experienced female psychologist. Open-ended questions were used to encourage participants to express their perceptions of surrogacy; prominent themes were discussed, compared, and combined. Results: Twenty women (mean age 31 years) agreed to participate. Key themes identified from interviews were the importance of having genetic offspring, consideration of surrogacy as a preferred solution to infertility, the barriers to surrogacy in Vietnam, lack of reproductive information and counselling, individuals concealing their health condition, the impact of religion on the possibility of surrogacy, the economic cost of surrogacy, and the difficulty in finding a surrogate under the restrictions imposed by Vietnamese law. Discussion: Based on the perceptions of women from MRKH from Vietnam, there is an opportunity to improve how infertility is managed in these people, including information about surrogacy. These data show that individuals with MRKH should be provided with information about the possibility of surrogacy, encouraged to be open and seek support, and be managed by a multidisciplinary team that includes psychological support; the provision of economic support for fertility treatments in women with MRKH should also be considered.

13.
J Reprod Immunol ; 163: 104241, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38492533

RESUMO

Epithelial ovarian cancer (OC) is the deadliest female reproductive cancer; an estimated 13,270 women will die from OC in 2023. Platinum-based chemotherapy resistance mechanisms contribute to poor OC 5-year survival rates. Peripheral inflammation is linked to various disease states and we previously identified unique peritoneal microbial features predictive of OC. We hypothesized that unique peripheral immune profiles and peritoneal microbial features may be predictive of disease-free interval (time to recurrence) and response to chemotherapy in participants with OC. We also investigated self-rated health (SRH) scores in the context of peripheral inflammation as a potential screening tool for OC. Blood and peritoneal fluid were collected from participants with OC or a benign adnexal mass (BPM). Lymphocyte populations were analyzed using Fluorescence Activated Cell Sorting, serum cytokine levels were analyzed using the Human Th17 Magnetic Bead Panel assay and peritoneal fluid microbial features were analyzed using Next Generation Sequencing (NGS). Participants completed a standardized questionnaire on self-rated physical and emotional health. Participants were classified into three chemotherapy response categories: platinum-refractory, platinum-resistant or platinum-sensitive. A significant positive correlation was found between elevated inflammatory status on the day of surgery and longer disease-free interval. SRH measures did not correlate with immune status in participants with OC or a BPM. We identified a correlation between peritoneal microbial features and chemotherapy response. We conclude that immune dysbiosis may be useful in predicting OC recurrence. The immune findings reported here set the framework for additional studies utilizing immune profiles to predict platinum-based chemotherapy responsiveness in OC.


Assuntos
Disbiose , Humanos , Feminino , Pessoa de Meia-Idade , Disbiose/imunologia , Adulto , Carcinoma Epitelial do Ovário/imunologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Idoso , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/imunologia , Prognóstico , Microbiota/imunologia , Microbiota/efeitos dos fármacos , Citocinas/metabolismo , Citocinas/sangue , Líquido Ascítico/imunologia , Líquido Ascítico/microbiologia
14.
MethodsX ; 12: 102624, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38435640

RESUMO

The mean sea surface in different regions is non-equipotential, rendering Vietnam's traditional approach, which relies on the Hon-Dau tide gauge station as a reference, not yet scientifically invalid. To overcome this, our study utilized the Vietnam national mean dynamic topography model (MDTVN22) for depth observations, particularly in the Gulf of Tonkin. Covering 3430 monitoring sites in Hai Phong and 813 sites in Quang Ninh, our experiments highlighted a 5 to 6 mm difference between the mean sea surface and MDTVN22 references. •Our research establishes a resilient methodology, integrating shore tide gauge station data and the MDTVN22 model, aimed at enhancing precision in depth observations.•Validation experiments in Hai Phong demonstrate a minimal discrepancy of ±0.006 m between measurements obtained from the traditional mean sea surface and the MDTVN22 model.•These findings underscore the significance of adopting the MDTVN22 model for improved accuracy in assessing Vietnam's seabed topography.

15.
ACS Omega ; 9(15): 16949-16958, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38645317

RESUMO

Three-dimensional (3D) cell culture systems are becoming increasingly popular due to their ability to mimic the complex process of angiogenesis in cancer, providing more accurate and physiologically relevant data than traditional two-dimensional (2D) cell culture systems. Microwell systems are particularly useful in this context as they provide a microenvironment that more closely resembles the in vivo environment than traditional microwells. Poly(ethylene glycol) (PEG) microwells are particularly advantageous due to their bio-inertness and the ability to tailor their material characteristics depending on the PEG molecular weight. Although there are several methods available for microwell fabrication, most of them are time-consuming and expensive. The current study utilizes a low-cost laser etching technique on poly(methyl methacrylate) materials followed by molding with PDMS to produce microwells. The optimal conditions for making concave microwells are an engraving parameter speed of 600 mm/s, power of 20%, and a design diameter of the microwell of 0.4 mm. The artificial tumor achieved its full size after 7 days of cell growth in a microwell system, and the cells developed drugs through a live/dead assay test. The results of the drug testing revealed that the IC50 value of zerumbone-loaded liposomes in HepG2 was 4.53 pM, which is greater than the IC50 value of zerumbone. The HepG2 cancer sphere's 3D platform for medication testing revealed that zerumbone-loaded liposomes were very effective at high doses. These findings generally imply that zerumbone-loaded liposomes have the capacity to target the liver and maintain medication delivery.

16.
Hum Genet ; 132(10): 1141-51, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23743675

RESUMO

Maximum number of alcoholic drinks consumed in a 24-h period (maxdrinks) is a heritable (>50 %) trait and is strongly correlated with vulnerability to excessive alcohol consumption and subsequent alcohol dependence (AD). Several genome-wide association studies (GWAS) have studied alcohol dependence, but few have concentrated on excessive alcohol consumption. We performed two GWAS using maxdrinks as an excessive alcohol consumption phenotype: one in 118 extended families (N = 2,322) selected from the Collaborative Study on the Genetics of Alcoholism (COGA), and the other in a case-control sample (N = 2,593) derived from the Study of Addiction: Genes and Environment (SAGE). The strongest association in the COGA families was detected with rs9523562 (p = 2.1 × 10(-6)) located in an intergenic region on chromosome 13q31.1; the strongest association in the SAGE dataset was with rs67666182 (p = 7.1 × 10(-7)), located in an intergenic region on chromosome 8. We also performed a meta-analysis with these two GWAS and demonstrated evidence of association in both datasets for the LMO1 (p = 7.2 × 10(-7)) and PLCL1 genes (p = 4.1 × 10(-6)) with maxdrinks. A variant in AUTS2 and variants in INADL, C15orf32 and HIP1 that were associated with measures of alcohol consumption in a meta-analysis of GWAS studies and a GWAS of alcohol consumption factor score also showed nominal association in the current meta-analysis. The present study has identified several loci that warrant further examination in independent samples. Among the top SNPs in each of the dataset (p ≤ 10(-4)) far more showed the same direction of effect in the other dataset than would be expected by chance (p = 2 × 10(-3), 3 × 10(-6)), suggesting that there are true signals among these top SNPs, even though no SNP reached genome-wide levels of significance.


Assuntos
Consumo de Bebidas Alcoólicas/genética , Alcoolismo/genética , Loci Gênicos , Genoma Humano , Estudo de Associação Genômica Ampla , Adulto , Cromossomos Humanos Par 13/genética , Proteínas de Ligação a DNA/genética , Feminino , Interação Gene-Ambiente , Predisposição Genética para Doença , Genética Populacional/métodos , Humanos , Proteínas com Domínio LIM/genética , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Fosfoinositídeo Fosfolipase C/genética , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética
17.
Mol Biol Cell ; 34(11): ar105, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37556227

RESUMO

Expression from transfected plasmid DNA is generally transient, but it is unclear what process terminates it. We show that DNA entering mammalian cells is rapidly surrounded by a double membrane in the cytoplasm, in some cases after leaving the nucleus. This cytoplasmic container, termed exclusome, frequently also contains extrachromosomal telomeric DNA, and is maintained by the cell over several division cycles. The exclusome envelope contains endoplasmic reticulum proteins and the inner-nuclear membrane proteins Lap2ß and Emerin, but differs from the nuclear envelope by its fenestrations and the absence of the Lamin B Receptor and nuclear pore complexes. Reduction of exclusome frequency upon overexpressing Emerin's LEM-domain suggests a role for Emerin in plasmid DNA compartmentalization. Thus, cells distinguish extrachromosomal DNA and chromosomes and wrap them into similar yet distinct envelopes keeping the former in the exclusome but the latter in the nucleus, where transcription occurs.


Assuntos
Núcleo Celular , Membrana Nuclear , Animais , Membrana Nuclear/metabolismo , Núcleo Celular/metabolismo , Poro Nuclear , Citoplasma , Cromossomos , Mamíferos
18.
Nat Commun ; 14(1): 1233, 2023 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-36871012

RESUMO

Deletion of the conserved C-terminus of the Rothmund-Thomson syndrome helicase RECQ4 is highly tumorigenic. However, while the RECQ4 N-terminus is known to facilitate DNA replication initiation, the function of its C-terminus remains unclear. Using an unbiased proteomic approach, we identify an interaction between the RECQ4 N-terminus and the anaphase-promoting complex/cyclosome (APC/C) on human chromatin. We further show that this interaction stabilizes APC/C co-activator CDH1 and enhances APC/C-dependent degradation of the replication inhibitor Geminin, allowing replication factors to accumulate on chromatin. In contrast, the function is blocked by the RECQ4 C-terminus, which binds to protein inhibitors of APC/C. A cancer-prone, C-terminal-deleted RECQ4 mutation increases origin firing frequency, accelerates G1/S transition, and supports abnormally high DNA content. Our study reveals a role of the human RECQ4 C-terminus in antagonizing its N-terminus, thereby suppressing replication initiation, and this suppression is impaired by oncogenic mutations.


Assuntos
Replicação do DNA , Proteômica , Humanos , Ciclossomo-Complexo Promotor de Anáfase , Cromatina , Fatores de Iniciação de Peptídeos
19.
PLoS One ; 18(2): e0281857, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36802388

RESUMO

INTRODUCTION: Increasing access to viral load (VL) monitoring is essential to fight HIV epidemics. In remote settings in Vietnam, using dried blood spot (DBS) sampling for specimen collection could improve the situation. Here, people who inject drugs (PWID) represent many newly antiretroviral therapy (ART)-initiated patients. The goals of this evaluation were to evaluate if access to VL monitoring and the rate of virological failure differed between PWID and non-PWID. METHODS: Prospective cohort study of patients newly initiated on ART in remote settings in Vietnam. DBS coverage at 6, 12 and 24 months of ART was investigated. Factors associated with DBS coverage were identified through logistic regression, as were factors associated with virological failure (VL ≥1,000 copies/mL) at 6, 12 and 24 months of ART. RESULTS: Overall 578 patients were enrolled in the cohort, of whom 261 (45%) were PWID. DBS coverage improved from 74.7% to 82.9% between 6 and 24 months of ART (p = 0.001). PWID status was not associated with DBS coverage (p = 0.74), but DBS coverage was lower in patients who were late to clinical visits and in those in WHO stage 4 (p = 0.023 and p = 0.001, respectively). The virological failure rate decreased from 15.8% to 6.6% between 6 and 24 months of ART (p<0.001). In multivariate analysis, PWID were more at risk of failure (p = 0.001), as were patients who were late to clinical visits (p<0.001) and not fully adherent (p<0.001). CONCLUSIONS: Despite training and simple procedures, DBS coverage was not perfect. DBS coverage was not associated with PWID status. Close management is required for effective routine HIV VL monitoring. PWID were more at risk of failure, as were patients who were not fully adherent and patients who were late to clinical visits. Specific interventions targeting these patients are needed to improve their outcomes. Overall, efforts in coordination and communication are essential to improve global HIV care. TRIAL REGISTRATION: Clinical Trial Number: NCT03249493.


Assuntos
Usuários de Drogas , Infecções por HIV , HIV-1 , Humanos , Estudos Prospectivos , Vietnã/epidemiologia , Carga Viral/métodos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia
20.
ScientificWorldJournal ; 2012: 982957, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22645501

RESUMO

Zinc-supplementation (20 µM) effects on growth, photosynthesis, antioxidant enzyme activities (superoxide dismutase, ascorbate peroxidase, catalase), and the expression of phytochelatin synthase gene were investigated in four marine diatoms (Amphora acutiuscula, Nitzschia palea, Amphora coffeaeformis and Entomoneis paludosa). Zn-supplementation reduced the maximum cell density. A linear relationship was found between the evolution of gross photosynthesis and total chlorophyll content. The Zn treatment decreased the electron transport rate except in A. coffeaeformis and in E. paludosa at high irradiance. A linear relationship was found between the efficiency of light to evolve oxygen and the size of the light-harvesting antenna. The external carbonic anhydrase activity was stimulated in Zn-supplemented E. paludosa but was not correlated with an increase of photosynthesis. The total activity of the antioxidant enzymes did not display any clear increase except in ascorbate peroxidase activity in N. palea. The phytochelatin synthase gene was identified in the four diatoms, but its expression was only revealed in N. palea, without a clear difference between control and Zn-supplemented cells. Among the four species, A. paludosa was the most sensitive and A. coffeaeformis, the most tolerant. A. acutiuscula seemed to be under metal starvation, whereas, to survive, only N. palea developed several stress responses.


Assuntos
Aminoaciltransferases/biossíntese , Aminoaciltransferases/genética , Diatomáceas/metabolismo , Zinco/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Carbono/química , Anidrases Carbônicas/metabolismo , Clorofila/química , Diatomáceas/efeitos dos fármacos , Elétrons , Luz , Metais/química , Fotossíntese , Reação em Cadeia da Polimerase/métodos , Temperatura , Zinco/química
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