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1.
Proc Natl Acad Sci U S A ; 119(30): e2201927119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35858426

RESUMO

Hepatitis B virus (HBV) DNA replication takes place inside the viral core particle and is dependent on autophagy. Here we show that HBV core particles are associated with autophagosomes and phagophores in cells that productively replicate HBV. These autophagic membrane-associated core particles contain almost entirely the hypophosphorylated core protein and are DNA replication competent. As the hyperphosphorylated core protein can be localized to phagophores and the dephosphorylation of the core protein is associated with the packaging of viral pregenomic RNA (pgRNA), these results are in support of the model that phagophores can serve as the sites for the packaging of pgRNA. In contrast, in cells that replicate HBV, the precore protein derivatives, which are related to the core protein, are associated with autophagosomes but not with phagophores via a pathway that is independent of its signal peptide. Interestingly, when the core protein is expressed by itself, it is associated with phagophores but not with autophagosomes. These observations indicate that autophagic membranes are differentially involved in the trafficking of precore and core proteins. HBV induces the fusion of autophagosomes and multivesicular bodies and the silencing of Rab11, a regulator of this fusion, is associated with the reduction of release of mature HBV particles. Our studies thus indicate that autophagic membranes participate in the assembly of HBV nucleocapsids, the trafficking of HBV precore and core proteins, and likely also the egress of HBV particles.


Assuntos
Autofagossomos , Vírus da Hepatite B , Nucleocapsídeo , Empacotamento do Genoma Viral , Replicação Viral , Autofagossomos/fisiologia , DNA Viral/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Humanos , Nucleocapsídeo/genética , Nucleocapsídeo/fisiologia , Transporte Proteico , RNA Viral/metabolismo , Replicação Viral/genética
2.
Microb Ecol ; 87(1): 45, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38393401

RESUMO

Fungal spores are common airborne allergens, and fungal richness has been implicated in allergic disease. Amplicon sequencing of environmental DNA from air samples is a promising method to estimate fungal spore richness with semi-quantification of hundreds of taxa and can be combined with quantitative PCR to derive abundance estimates. However, it remains unclear how the choice of air sampling method influences these estimates. This study compared active sampling with a portable impactor and passive sampling with a passive trap over different durations to estimate fungal spore richness and the abundance of allergenic taxa. Air sampling was conducted indoors and outdoors at 12 residences, including repeated measurements with a portable impactor and passive traps with 1-day and 7-day durations. ITS2 amplicon sequence data were transformed to spore equivalents estimated by quantitative PCR, repeated active samples were combined, and abundance-based rarefaction was performed to standardize sample coverage for estimation of genus-level richness and spore abundance. Rarefied fungal richness was similar between methods indoors but higher for passive traps with a 7-day duration outdoors. Rarefied abundance of allergenic genera was similar between methods but some genera had lower abundance for passive traps with a 1-day duration, which differed indoors and outdoors indicating stochasticity in the collection of spores on collocated samplers. This study found that similar estimates of fungal spore richness and abundance of allergenic taxa can be obtained using a portable impactor or a passive trap within one day and that increased passive sample duration provides limited additional information.


Assuntos
Alérgenos , Fungos , Esporos Fúngicos/genética , Fungos/genética , Microbiologia do Ar , Monitoramento Ambiental
3.
Alzheimers Dement ; 20(4): 2353-2363, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38284802

RESUMO

INTRODUCTION: Clinical understanding of primary progressive aphasia (PPA) has been primarily derived from Indo-European languages. Generalizing certain linguistic findings across languages is unfitting due to contrasting linguistic structures. While PPA patients showed noun classes impairments, Chinese languages lack noun classes. Instead, Chinese languages are classifier language, and how PPA patients manipulate classifiers is unknown. METHODS: We included 74 native Chinese speakers (22 controls, 52 PPA). For classifier production task, participants were asked to produce the classifiers of high-frequency items. In a classifier recognition task, participants were asked to choose the correct classifier. RESULTS: Both semantic variant (sv) PPA and logopenic variant (lv) PPA scored significantly lower in classifier production task. In classifier recognition task, lvPPA patients outperformed svPPA patients. The classifier production scores were correlated to cortical volume over left temporal and visual association cortices. DISCUSSION: This study highlights noun classifiers as linguistic markers to discriminate PPA syndromes in Chinese speakers. HIGHLIGHTS: Noun classifier processing varies in the different primary progressive aphasia (PPA) variants. Specifically, semantic variant PPA (svPPA) and logopenic variant PPA (lvPPA) patients showed significantly lower ability in producing specific classifiers. Compared to lvPPA, svPPA patients were less able to choose the accurate classifiers when presented with choices. In svPPA, classifier production score was positively correlated with gray matter volume over bilateral temporal and left visual association cortices in svPPA. Conversely, classifier production performance was correlated with volumetric changes over left ventral temporal and bilateral frontal regions in lvPPA. Comparable performance of mass and count classifier were noted in Chinese PPA patients, suggesting a common cognitive process between mass and count classifiers in Chinese languages.


Assuntos
Afasia Primária Progressiva , Humanos , Afasia Primária Progressiva/diagnóstico , Idioma , Substância Cinzenta , Córtex Cerebral
4.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203299

RESUMO

Terpenoids are the largest class of plant secondary metabolites and are one of the major emitted volatile compounds released to the atmosphere. They have functions of attracting pollinators or defense function, insecticidal properties, and are even used as pharmaceutical agents. Because of the importance of terpenoids, an increasing number of plants are required to investigate the function and evolution of terpene synthases (TPSs) that are the key enzymes in terpenoids biosynthesis. Orchidacea, containing more than 800 genera and 28,000 species, is one of the largest and most diverse families of flowering plants, and is widely distributed. Here, the diversification of the TPSs evolution in Orchidaceae is revealed. A characterization and phylogeny of TPSs from four different species with whole genome sequences is available. Phylogenetic analysis of orchid TPSs indicates these genes are divided into TPS-a, -b, -e/f, and g subfamilies, and their duplicated copies are increased in derived orchid species compared to that in the early divergence orchid, A. shenzhenica. The large increase of both TPS-a and TPS-b copies can probably be attributed to the pro-duction of different volatile compounds for attracting pollinators or generating chemical defenses in derived orchid lineages; while the duplications of TPS-g and TPS-e/f copies occurred in a species-dependent manner.


Assuntos
Alquil e Aril Transferases/metabolismo , Orchidaceae/enzimologia , Proteínas de Plantas/metabolismo , Alquil e Aril Transferases/genética , Evolução Molecular , Filogenia , Proteínas de Plantas/genética
5.
BMC Plant Biol ; 19(1): 337, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375064

RESUMO

BACKGROUND: Cymbidium goeringii belongs to the Orchidaceae, which is one of the most abundant angiosperm families. Cymbidium goeringii consist with high economic value and characteristics include fragrance and multiple flower colors. Floral scent is one of the important strategies for ensuring fertilization. However, limited genetic data is available in this non-model plant, and little known about the molecular mechanism responsible for floral scent in this orchid. Transcriptome and expression profiling data are needed to identify genes and better understand the biological mechanisms of floral scents in this species. Present transcriptomic data provides basic information on the genes and enzymes related to and pathways involved in flower secondary metabolism in this plant. RESULTS: In this study, RNA sequencing analyses were performed to identify changes in gene expression and biological pathways related scent metabolism. Three cDNA libraries were obtained from three developmental floral stages: closed bud, half flowering stage and full flowering stage. Using Illumina technique 159,616,374 clean reads were obtained and were assembled into 85,868 final unigenes (average length 1194 nt), 33.85% of which were annotated in the NCBI non redundant protein database. Among this unigenes 36,082 were assigned to gene ontology and 23,164 were combined with COG groups. Total 33,417 unigenes were assigned in 127 pathways according to the Kyoto Encyclopedia of Genes and Genomes pathway database. According these transcriptomic data we identified number of candidates genes which differentially expressed in different developmental stages of flower related to fragrance biosynthesis. In q-RT-PCR most of the fragrance related genes highly expressed in half flowering stage. CONCLUSIONS: RNA-seq and DEG data provided comprehensive gene expression information at the transcriptional level that could be facilitate the molecular mechanisms of floral biosynthesis pathways in three developmental phase's flowers in Cymbidium goeringii, moreover providing useful information for further analysis on C. goeringii, and other plants of genus Cymbidium.


Assuntos
Flores/metabolismo , Genes de Plantas/genética , Odorantes , Orchidaceae/genética , Acetatos/metabolismo , Ciclopentanos/metabolismo , Farneseno Álcool/metabolismo , Flores/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/fisiologia , Orchidaceae/metabolismo , Oxilipinas/metabolismo , Filogenia , Análise de Sequência de RNA , Sesquiterpenos/metabolismo , Terpenos/metabolismo
6.
Pediatr Allergy Immunol ; 30(2): 188-194, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30371957

RESUMO

BACKGROUND: Childhood asthma is a common disease whose prevalence is changing. Shift in environmental exposure was one of the plausible explanations. This study investigated changes in the association between childhood asthma and ambient air pollution occurring over time. METHOD: A nationwide questionnaire survey concerning respiratory illness and symptoms was administered to Taiwanese elementary and middle school students in 2011 and repeatedly in 2016-2017. During the study period, the concentrations of ambient air pollutants were obtained from the Environmental Protection Administration (EPA) monitoring stations. Generalized estimating equation models were applied to examine the association between air pollution in the past year and the risk of current asthma. RESULTS: A total of 6346 children from the 2011 survey and 11 585 children from the 2016-2017 survey attended schools located within a 1-km radius of Taiwan EPA monitoring stations. The prevalence of childhood current asthma (children with physician-diagnosed asthma and persistent asthma symptoms in the past year) increased from 7.5% to 9.6% during this period. The level of exposure to particulate matter with an aerodynamic diameter of ≤2.5 µm (PM2.5 ) in the past year was found to be associated with current asthma both in the 2011 survey (odds ratio (OR): 1.90, 95% confidence interval (CI): 1.41-2.57) and in the 2016-2017 survey (OR: 1.24, 95% CI: 1.04-1.48). CONCLUSION: Improved air quality has reduced the effect of PM2.5 on childhood asthma, but air quality remains a health concern in Taiwan.


Assuntos
Poluentes Atmosféricos/imunologia , Poluição do Ar/efeitos adversos , Asma/etiologia , Exposição Ambiental/efeitos adversos , Adolescente , Asma/epidemiologia , Criança , Estudos Transversais , Monitoramento Ambiental/estatística & dados numéricos , Feminino , Humanos , Masculino , Material Particulado/efeitos adversos , Material Particulado/imunologia , Prevalência , Fatores de Risco , Instituições Acadêmicas , Taiwan/epidemiologia
7.
Environ Res ; 179(Pt B): 108809, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31678729

RESUMO

BACKGROUND: Exposure to ambient fine particles, particulate matter with an aerodynamic diameter of ≤2.5 µm (PM2.5), is a public health concern. Concentrations of ambient PM2.5 have changed temporally in the past 10 years after a series of action policies for improving air quality were implemented in Taiwan. In this study, temporal changes in the relationship between PM2.5 and lung function among children were investigated. METHODS: A nationwide respiratory health survey was conducted among Taiwanese elementary and middle school students in 2011 and again in 2016-2017. A questionnaire was administered to students, for whom forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were measured using spirometry. During the study period, monthly concentrations of ambient PM2.5 were obtained from the monitoring stations of the Environmental Protection Administration. Lung function measurements were compared with ambient PM2.5 exposure using mixed-effects models. RESULTS: In the 2011 survey (mean PM2.5: 40.6 µg/m3), exposure to PM2.5 in the preceding 1-2 months was associated with a 2.2% decrease (95% confidence interval [CI]: -4.1%, -0.3%) in FVC and a 2.3% decrease (95% CI: -4.0%, -0.5%) in FEV1. By contrast, a significant relationship between PM2.5 concentrations and lung function was not observed in the 2016-2017 survey (mean PM2.5: 30.0 µg/m3). CONCLUSIONS: As improvement in air quality over time, the negative relationship between PM2.5 and childhood lung function tend to be not significant.


Assuntos
Poluentes Atmosféricos , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Pulmão/fisiologia , Material Particulado , Criança , Humanos , Taiwan
8.
Environ Res ; 170: 481-486, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30640082

RESUMO

Epigenome-wide DNA methylation has not been studied in men perinatally exposed to PCBs and dioxins. Therefore, we examined whether perinatal exposure to polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs) induces sustained methylation changes lasting to early adulthood. We used the Illumina HumanMethylation450 BeadChip to assess DNA methylation in whole blood among Yucheng second generation (people perinatal exposed to high PCBs and PCDFs) compared with referents. Thirty male offspring from the Yucheng cohort were randomly selected and matched with 30 male offspring from the Yucheng' neighborhood referents with similar backgrounds. Methylation differences between the Yucheng second generation and non-exposed referents were identified using a P value < 1.06 × 10-7. Differential DNA methylation with epigenome-wide statistical significance was observed for 20 CpGs mapped to 11 genes, and 19 CpGs were correlated with gestational levels of PCBs or PCDF toxic equivalency (PCDF-TEQ) with the same direction of effect. Among the 11 genes, AHRR and CYP1A1 are involved in the aryl hydrocarbon receptor signaling pathway known to mediate dioxin toxicity. MYO1G, FRMD4A, ARL4C, OLFM1, and WWC3 were previously reported to be related to carcinogenesis. This is the first study examining genome-wide DNA methylation among people perinatally exposed to high concentrations of PCBs and PCDFs. We observed novel differential methylation of several genes, indicating that modifications of DNA methylation associated with perinatal PCB and PCDF exposure may persist in exposed offspring for more than 20 years. Furthermore, involvement of several carcinogesis-related genes suggested a potential in utero epigenetic mechanisms.


Assuntos
Dibenzofuranos Policlorados/toxicidade , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/toxicidade , Bifenilos Policlorados/toxicidade , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Fatores de Ribosilação do ADP , Adulto , Benzofuranos , Metilação de DNA , Dibenzofuranos Policlorados/metabolismo , Poluentes Ambientais/metabolismo , Características da Família , Feminino , Humanos , Masculino , Bifenilos Policlorados/metabolismo , Gravidez
9.
J Exp Bot ; 69(18): 4363-4377, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-29982590

RESUMO

Floral scent is an important factor in attracting pollinators and repelling florivores. In Phalaenopsis bellina (Orchidaceae), the major floral scent components are monoterpenoids. Previously, we determined that expression of GERANYL DIPHOSPHATE SYNTHASE (PbGDPS) is highly correlated with monoterpene biosynthesis in Phalaenosis orchids. Here, we found that both cis- and trans-regulation were present on the GDPS promoters, with trans-regulation playing a key role. To investigate the regulation of biosynthesis of floral scent, we compared the transcriptomic data of two Phalaenopsis orchids with contrasting scent phenotypes. Eight transcription factors (TFs) that exhibited sequential elevation in abundance through floral development in P. bellina were identified, and their transcript levels were higher in the scented orchid than the scentless one. Five of these TFs transactivated several structural genes involved in monoterpene biosynthesis including PbbHLH4, PbbHLH6, PbbZIP4, PbERF1, and PbNAC1. Ectopic transient expression of each of these TFs in scentless orchids resulted in stimulation of terpenoid biosynthesis. PbbHLH4 most profoundly induced monoterpene biosynthesis, with a 950-fold increase of monoterpenoid production in the scentless orchid. In conclusion, we determined that biosynthesis of orchid floral monoterpenes was sequentially regulated, with PbbHLH4 playing a crucial role for monoterpene biosynthesis.


Assuntos
Regulação da Expressão Gênica de Plantas , Monoterpenos/metabolismo , Orchidaceae/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Transcriptoma , Flores/metabolismo , Odorantes/análise , Orchidaceae/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
10.
Carcinogenesis ; 38(3): 336-345, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28426879

RESUMO

Di-(2-ethylhexyl) phthalate (DEHP), the common plasticizer used in the production of polyvinyl chloride, can be converted to the more potent metabolite mono-ethylhexyl phthalate (MEHP). Epidemiological studies have shown an association with elevated induction of rat hepatic cancer and reproductive toxicity in response to MEHP exposure. However, the mechanism of genotoxicity and carcinogenicity induced by MEHP treatment remains unclear. As a means to elucidate the mechanisms of action, lethality and mutagenicity in the adenine phosphoribosyltransferase (aprt+/-) gene induced in several CHO cell types by MEHP were assessed. Dose-response relationships were determined in the parental AA8 cell line, its nucleotide repair-deficient UV5 and base repair-deficient EM9 subclones, and also in AS52 cells harboring the bacterial guanine-hypoxanthine phosphoribosyltransferase (gpt) gene and its derived AS52-XPD-knockdown and AS52-PARP-1-knockdown cells. Treatment of AS52 with MEHP led to intracellular production of reactive oxygen species (ROS) and DNA strand breaks in a dose-dependent manner. Separately, mutations in the gpt gene of AS52 cells were characterized and found to be dominated by G:C to A:T and A:T to G:C transitions. Independent AS52-mutant cell (ASMC) clones were collected for the sequential in vivo xenograft tumorigenic studies, 4 of total 20 clones had aggressive tumor growth. Moreover, microarray analysis indicated miR-let-7a and miR-125b downregulated in ASMC, which might raise oncogenic MYC and RAS level and activate ErbB pathway. Comparative evaluation of the results indicates that the principal mechanism of this mutagenic action is probably to be through generation of ROS, causing base excision damage resulting in carcinogenicity.


Assuntos
Dietilexilftalato/análogos & derivados , Dietilexilftalato/metabolismo , Mutagênese/genética , Poli(ADP-Ribose) Polimerase-1/genética , Animais , Células CHO , Cricetinae , Cricetulus , Dano ao DNA/efeitos dos fármacos , Humanos , Mutagênese/efeitos dos fármacos , Testes de Mutagenicidade , Mutação/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
11.
Environ Toxicol ; 32(4): 1412-1425, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27539004

RESUMO

PM2.5 travels along the respiratory tract and enters systemic blood circulation. Studies have shown that PM2.5 increases the incidence of various diseases not only in adults but also in newborn infants. It causes chronic inflammation in pregnant women and retards fetal development. In this study, pregnant rats were exposed to PM2.5 for extended periods of time and it was found that PM2.5 exposure increased immune cells in mother rats. In addition, cytokines and free radicals rapidly accumulated in the amniotic fluid and indirectly affected the fetuses. The authors collected cerebral cortex and hippocampus samples at E18 and analyzed changes of miRNA levels. Expression levels of cortical miR-6315, miR-3588, and miR-466b-5p were upregulated, and positively correlated with the genes Pkn2 (astrocyte migration), Gorab (neuritogenesis), and Mobp (allergic encephalomyelitis). In contrast, PM2.5 decreased expression of miR-338-5p and let-7e-5p, both related to mental development. Further, PM2.5 exposure increased miR-3560 and let-7b-5p in the hippocampus, two proteins that regulate genes Oxct1 and Lin28b that control ketogenesis and glycosylation, and neural cell differentiation, respectively. miR-99b-5p, miR-92b-5p, and miR-99a-5p were decreased, leading to reduced expression of Kbtbd8 and Adam11 which reduced cell mitosis, migration, and differentiation, and inhibited learning abilities and motor coordination of the fetus. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1412-1425, 2017.


Assuntos
Poluentes Atmosféricos/toxicidade , Hipocampo/efeitos dos fármacos , Exposição Materna , Material Particulado/toxicidade , Adulto , Líquido Amniótico/efeitos dos fármacos , Líquido Amniótico/metabolismo , Animais , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Troca Materno-Fetal , MicroRNAs/biossíntese , MicroRNAs/genética , Gravidez , Ratos , Ratos Sprague-Dawley , Transcriptoma/efeitos dos fármacos
12.
Environ Res ; 149: 145-150, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27208465

RESUMO

BACKGROUND: We recently reported the relationship between exposure to ambient air pollutants and changes in lung function and nasal inflammation among schoolchildren. A study was conducted to investigate whether antioxidation genotypes influence these associations. METHODS: A follow-up study of 97 schoolchildren was conducted in New Taipei City, Taiwan. A structured respiratory health questionnaire was administered in September 2007, followed by monthly spirometry and measurement of nasal inflammation from October 2007 to November 2009. During the study period, complete daily monitoring data for air pollutants were obtained from the Environmental Protection Administration monitoring station and Aerosol Supersite. The genotypes of glutathione S-transferase (GST) subunits M1, T1, P1 and superoxide dismutases subunit 2 (SOD2) were characterized. Mixed-effects models were used, adjusting for known confounders. RESULT: GSTM1 null children had significant PM2.5-related increment in leukocyte (8.52%; 95% confidence interval (CI): 3.13-13.92%) and neutrophil (9.68%; 95% CI: 4.51-14.85%) in nasal lavage. Ozone levels were significantly and inversely associated with forced expiratory flow at 25% of forced vital capacity (FEF25%) (-0.43L/s; 95% CI: -0.58,-0.28L/s) in SOD2 Ala16 variant children. CONCLUSION: In this longitudinal study of schoolchildren. Our data provide evidence that antioxidation genotype modifies the airway inflammation caused by PM2.5. Antioxidation genotype also acts as an effect modifier, but not strong, in ozone-related small airway function response.


Assuntos
Poluentes Atmosféricos/toxicidade , Inflamação/genética , Exposição por Inalação , Doenças Respiratórias/genética , Adolescente , Antioxidantes/metabolismo , Criança , Cidades , Monitoramento Ambiental , Feminino , Seguimentos , Genótipo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Inflamação/induzido quimicamente , Estudos Longitudinais , Masculino , Oxirredução/efeitos dos fármacos , Testes de Função Respiratória , Doenças Respiratórias/induzido quimicamente , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Taiwan
13.
Soft Matter ; 10(19): 3394-403, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24643481

RESUMO

The evaporation process of a sessile drop of water on soft patterned polydimethylsiloxane (PDMS) substrates is investigated in this study. Different softness of a regular pillar-like patterned PDMS substrate can be achieved by controlling the mixing ratio of a PDMS's prepolymer base and a curing agent at 10 : 1, 20 : 1 and 30 : 1. The receding contact angle is smaller for softer pillar-like patterned substrates. Consequently, the evaporation rate is faster on softer pillar-like substrates. A sessile drop on the regular pillar-like PDMS substrates, prepared at the mixing ratio of a base to a curing agent of 10 : 1 and 20 : 1, is observed to start evaporating in the constant contact radius (CCR) mode then switching to the constant contact angle (CCA) mode via stepwise jumping of the contact line, and finally shifting to the mixed mode sequentially. During the evaporation, a wetting transition from the Cassie to the Wenzel state occurs earlier for the softer substrate because softer pillars relatively cannot stand the increasingly high Laplace pressure. For the softest regular pillar-like PDMS substrate prepared at the mixing ratio of the base to the curing agent of 30 : 1 (abbreviated by PDMS-30 : 1 substrate), the pillars collapse irreversibly after the sessile drop exhibits the wetting transition into the Wenzel state. Furthermore, it is interesting to find out that the initial stage of evaporation of a sessile drop on the PDMS-30 : 1 substrate in the Cassie state is in the CCR mode followed by the CCA mode with stepwise retreatment of the contact line. Further evaporation would induce the wetting transition from the Cassie to the Wenzel state (due to the collapse of pillars) and resume the CCR mode followed by the CCA mode again sequentially.

14.
Microbiol Mol Biol Rev ; : e0001424, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39440957

RESUMO

SUMMARYHepatitis B virus (HBV) is an important human pathogen that chronically infects approximately 250 million people in the world, resulting in ~1 million deaths annually. This virus is a hepatotropic virus and can cause severe liver diseases including cirrhosis and hepatocellular carcinoma. The entry of HBV into hepatocytes is initiated by the interaction of its envelope proteins with its receptors. This is followed by the delivery of the viral nucleocapsid to the nucleus for the release of its genomic DNA and the transcription of viral RNAs. The assembly of the viral capsid particles may then take place in the nucleus or the cytoplasm and may involve cellular membranes. This is followed by the egress of the virus from infected cells. In recent years, significant research progresses had been made toward understanding the entry, the assembly, and the egress of HBV particles. In this review, we discuss the molecular pathways of these processes and compare them with those used by hepatitis delta virus and hepatitis C virus , two other hepatotropic viruses that are also enveloped. The understanding of these processes will help us to understand how HBV replicates and causes diseases, which will help to improve the treatments for HBV patients.

15.
J Chin Med Assoc ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39350480

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) causes persistent symptoms, including brain fog. Based on limited research on the long-term consequences of mild COVID-19, which has yielded inconsistent results, we investigated which cognitive functions were most affected by COVID-19 in non-hospitalized Asian patients with long-term COVID and subjective cognitive complaints. METHODS: Fifty-five non-hospitalized patients with long COVID and brain fog (24 males and 31 females, mean age: 45.6 ± 14.6 years, mean duration of education: 14.4 ± 3.0 years) were recruited. Neuropsychological assessments included screening tests for overall cognition, and comprehensive tests for memory, executive function, processing speed, and subjective emotional and disease symptoms. Cognitive test scores were converted into Z-scores. Moreover, principal component analysis (PCA) was employed to define cognitive domains across subtest scores. RESULTS: Comprehensive assessments revealed cognitive impairment in 69.1% of patients (<1.5 standard deviation in at least one test). The processing speed (27.3%), memory recall (21.8%), memory learning (20.0%), and inhibitory control (18.2%) were the most affected areas. Self-reported anxiety and depression were observed in 35% and 33% of patients, respectively. Furthermore, the degree of self-anxiety can be used to predict learning performance. CONCLUSION: Nearly 70% of patients with subjective cognitive complaints and long COVID had objective cognitive impairments. A comprehensive evaluation is essential for patients with long COVID and brain fog, including those with mild symptoms.

16.
Sci Rep ; 14(1): 4580, 2024 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-38403657

RESUMO

Hypertension (HTN) affects over 1.2 billion individuals worldwide and is defined as systolic blood pressure (BP) ≥ 140 mmHg and diastolic BP ≥ 90 mmHg. Hypertension is also considered a high risk factor for cerebrovascular diseases, which may lead to vascular cognitive impairment (VCI). VCI is associated with executive dysfunction and is also a transitional stage between hypertension and vascular dementia. Hence, it is essential to establish a reliable approach to diagnosing the severity of VCI. In 28 HTN (51-83 yrs; 18 males, 10 females) and 28 healthy controls (HC) (51-75 yrs; 7 males, 21 females), we investigated which regions demonstrate alterations in the resting-state functional connectome due to vascular cognitive impairment in HTN by using the amplitude of the low-frequency fluctuations (ALFF), regional homogeneity (ReHo), graph theoretical analysis (GTA), and network-based statistic (NBS) methods. In the group comparison between ALFF/ReHo, HTN showed reduced spontaneous activity in the regions corresponding to vascular or metabolic dysfunction and enhanced brain activity, mainly in the primary somatosensory cortex and prefrontal areas. We also observed cognitive dysfunction in HTN, such as executive function, processing speed, and memory. Both the GTA and NBS analyses indicated that the HTN demonstrated complex local segregation, worse global integration, and weak functional connectivity. Our findings show that resting-state functional connectivity was altered, particularly in the frontal and parietal regions, by hypertensive individuals with potential vascular cognitive impairment.


Assuntos
Disfunção Cognitiva , Conectoma , Hipertensão , Masculino , Feminino , Humanos , Conectoma/métodos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Hipertensão/complicações , Mapeamento Encefálico
17.
J Exp Clin Cancer Res ; 43(1): 169, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38880883

RESUMO

BACKGROUND: Cancer is characterized by dysregulated cellular metabolism. Thus, understanding the mechanisms underlying these metabolic alterations is important for developing targeted therapies. In this study, we investigated the pro-tumoral effect of PDZ and LIM domain 2 (PDLIM2) downregulation in lung cancer growth and its association with the accumulation of mitochondrial ROS, oncometabolites and the activation of hypoxia-inducible factor-1 (HIF-1) α in the process. METHODS: Databases and human cancer tissue samples were analyzed to investigate the roles of PDLIM2 and HIF-1α in cancer growth. DNA microarray and gene ontology enrichment analyses were performed to determine the cellular functions of PDLIM2. Seahorse assay, flow cytometric analysis, and confocal microscopic analysis were employed to study mitochondrial functions. Oncometabolites were analyzed using liquid chromatography-mass spectrometry (LC-MS). A Lewis lung carcinoma (LLC) mouse model was established to assess the in vivo function of PDLIM2 and HIF-1α. RESULTS: The expression of PDLIM2 was downregulated in lung cancer, and this downregulation correlated with poor prognosis in patients. PDLIM2 highly regulated genes associated with mitochondrial functions. Mechanistically, PDLIM2 downregulation resulted in NF-κB activation, impaired expression of tricarboxylic acid (TCA) cycle genes particularly the succinate dehydrogenase (SDH) genes, and mitochondrial dysfunction. This disturbance contributed to the accumulation of succinate and other oncometabolites, as well as the buildup of mitochondrial reactive oxygen species (mtROS), leading to the activation of hypoxia-inducible factor 1α (HIF-1α). Furthermore, the expression of HIF-1α was increased in all stages of lung cancer. The expression of PDLIM2 and HIF-1α was reversely correlated in lung cancer patients. In the animal study, the orally administered HIF-1α inhibitor, PX-478, significantly reduces PDLIM2 knockdown-promoted tumor growth. CONCLUSION: These findings shed light on the complex action of PDLIM2 on mitochondria and HIF-1α activities in lung cancer, emphasizing the role of HIF-1α in the tumor-promoting effect of PDLIM2 downregulation. Additionally, they provide new insights into a strategy for precise targeted treatment by suggesting that HIF-1α inhibitors may serve as therapy for lung cancer patients with PDLIM2 downregulation.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Proteínas com Domínio LIM , Mitocôndrias , Espécies Reativas de Oxigênio , Animais , Feminino , Humanos , Masculino , Camundongos , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Carcinoma Pulmonar de Lewis/genética , Linhagem Celular Tumoral , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Proteínas com Domínio LIM/metabolismo , Proteínas com Domínio LIM/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/genética , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
18.
Autophagy ; 19(4): 1357-1358, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36037301

RESUMO

Autophagy (i.e. macroautophagy) plays a significant role in the replication of hepatitis B virus (HBV). In our recent study, we examined the underlying mechanism and discovered that autophagic membranes participated in different steps of the HBV life cycle. We found that phagophores are involved in the assembly of HBV nucleocapsids, autophagosomes participate in the trafficking of HBV nucleocapsids, amphisomes likely participate in the maturation and egress of mature HBV particles, and autolysosomes negatively regulate HBV replication. Our work provides important insights for understanding the relationship between autophagic membranes and HBV replication and raises the possibility of targeting the autophagic pathway for the development of novel drugs against HBV.


Assuntos
Vírus da Hepatite B , Hepatite B , Humanos , Vírus da Hepatite B/fisiologia , Autofagia , Replicação Viral/fisiologia , Autofagossomos/metabolismo , Hepatite B/metabolismo
19.
Virulence ; 13(1): 258-296, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35100095

RESUMO

Hepatitis B virus (HBV) is a hepatotropic virus and an important human pathogen. There are an estimated 296 million people in the world that are chronically infected by this virus, and many of them will develop severe liver diseases including hepatitis, cirrhosis and hepatocellular carcinoma (HCC). HBV is a small DNA virus that replicates via the reverse transcription pathway. In this review, we summarize the molecular pathways that govern the replication of HBV and its interactions with host cells. We also discuss viral and non-viral factors that are associated with HBV-induced carcinogenesis and pathogenesis, as well as the role of host immune responses in HBV persistence and liver pathogenesis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Vírus da Hepatite B/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Virulência
20.
Brain Imaging Behav ; 16(4): 1761-1775, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35294980

RESUMO

An association has been shown between chronic cigarette smoking and structural abnormalities in the brain areas related to several functions relevant to addictive behavior. However, few studies have focused on the structural alternations of chronic smoking by using magnetic resonance imaging (MRI). Also, it remains unclear how structural alternations are associated with tobacco-dependence severity and the positive/negative outcome expectances. The q-sampling imaging (GQI) is an advanced diffusion MRI technique that can reconstruct more precise and consistent images of complex oriented fibers than other methods. We aimed to use GQI to evaluate the impact of the neurological structure caused by chronic smoking. Sixty-seven chronic smokers and 43 nonsmokers underwent a MRI scan. The tobacco dependence severity and the positive/negative outcome expectancies were assessed via self-report. We used GQI with voxel-based statistical analysis (VBA) to evaluate structural brain and connectivity abnormalities. Graph theoretical analysis (GTA) and network-based statistical (NBS) analysis were also performed to identify the structural network differences among groups. Chronic smokers had smaller GM and WM volumes in the bilateral frontal lobe and bilateral frontal region. The GM/WM volumes correlated with dependence severity and outcome expectancies in the brain areas involving high-level functions. Chronic smokers had shape changes in the left hippocampal head and tail and the inferior brain stem. Poorer WM integrity in chronic smokers was found in the left middle frontal region, the right superior fronto-occipital fasciculus, the right temporal region, the left parahippocampus, the left anterior internal capsule, and the right inferior parietal region. WM integrity correlated with dependence severity and outcome expectancies in brain areas involving high-level functions. Chronic smokers had decreased local segregation and global integration among the brain regions and networks. Our results provide further evidence indicating that chronic smoking may be associated with brain structure and connectivity changes.


Assuntos
Conectoma , Tabagismo , Substância Branca , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Fumantes , Tabagismo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
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