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1.
J Biol Chem ; 300(2): 105637, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199564

RESUMO

Life adapts to daily environmental changes through circadian rhythms, exhibiting spontaneous oscillations of biological processes. These daily functional oscillations must match the metabolic requirements responding to the time of the day. We focus on the molecular mechanism of how the circadian clock regulates glucose, the primary resource for energy production and other biosynthetic pathways. The complex regulation of the circadian rhythm includes many proteins that control this process at the transcriptional and translational levels and by protein-protein interactions. We have investigated the action of one of these proteins, cryptochrome (CRY), whose elevated mRNA and protein levels repress the function of an activator in the transcription-translation feedback loop, and this activator causes elevated Cry1 mRNA. We used a genome-edited cell line model to investigate downstream genes affected explicitly by the repressor CRY. We found that CRY can repress glycolytic genes, particularly that of the gatekeeper, pyruvate dehydrogenase kinase 1 (Pdk1), decreasing lactate accumulation and glucose utilization. CRY1-mediated decrease of Pdk1 expression can also be observed in a breast cancer cell line MDA-MB-231, whose glycolysis is associated with Pdk1 expression. We also found that exogenous expression of CRY1 in the MDA-MB-231 decreases glucose usage and growth rate. Furthermore, reduced CRY1 levels and the increased phosphorylation of PDK1 substrate were observed when cells were grown in suspension compared to cells grown in adhesion. Our data supports a model that the transcription-translation feedback loop can regulate the glucose metabolic pathway through Pdk1 gene expression according to the time of the day.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Criptocromos , Piruvato Desidrogenase Quinase de Transferência de Acetil , Linhagem Celular , Relógios Circadianos/fisiologia , Criptocromos/metabolismo , RNA Mensageiro/genética , Humanos , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo
2.
J Virol ; 98(4): e0177323, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38530012

RESUMO

Dengue vaccine candidates have been shown to improve vaccine safety and efficacy by altering the residues or accessibility of the fusion loop on the virus envelope protein domain II (DIIFL) in an ex vivo animal study. The current study aimed to comprehensively investigate the impact of DIIFL mutations on the antigenicity, immunogenicity, and protective efficacy of Japanese encephalitis virus (JEV) virus-like particles (VLPs) in mice. We found the DIIFL G106K/L107D (KD) and W101G/G106K/L107D (GKD) mutations altered the binding activity of JEV VLP to cross-reactive monoclonal antibodies but had no effect on their ability to elicit total IgG antibodies in mice. However, JEV VLPs with KD or GKD mutations induced significantly less neutralizing antibodies against JEV. Only 46% and 31% of the KD and GKD VLPs-immunized mice survived compared to 100% of the wild-type (WT) VLP-immunized mice after a lethal JEV challenge. In passive protection experiments, naïve mice that received sera from WT VLP-immunized mice exhibited a significantly higher survival rate of 46.7% compared to those receiving sera from KD VLP- and GKD VLP-immunized mice (6.7% and 0%, respectively). This study demonstrated that JEV DIIFL is crucial for eliciting potently neutralizing antibodies and protective immunity against JEV. IMPORTANCE: Introduction of mutations into the fusion loop is one potential strategy for generating safe dengue and Zika vaccines by reducing the risk of severe dengue following subsequent infections, and for constructing live-attenuated vaccine candidates against newly emerging Japanese encephalitis virus (JEV) or Japanese encephalitis (JE) serocomplex virus. The monoclonal antibody studies indicated the fusion loop of JE serocomplex viruses primarily comprised non-neutralizing epitopes. However, the present study demonstrates that the JEV fusion loop plays a critical role in eliciting protective immunity in mice. Modifications to the fusion loop of JE serocomplex viruses might negatively affect vaccine efficacy compared to dengue and zika serocomplex viruses. Further studies are required to assess the impact of mutant fusion loop encoded by commonly used JEV vaccine strains on vaccine efficacy or safety after subsequent dengue virus infection.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Vacinas contra Encefalite Japonesa , Animais , Camundongos , Aminoácidos , Anticorpos Neutralizantes , Anticorpos Antivirais , Dengue , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Encefalite Japonesa/imunologia , Encefalite Japonesa/prevenção & controle , Epitopos , Vacinas contra Encefalite Japonesa/genética , Proteínas do Envelope Viral/genética , Zika virus , Infecção por Zika virus
3.
J Virol ; 98(2): e0189923, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294245

RESUMO

After Epstein-Barr virus (EBV) genome replication and encapsidation in the nucleus, nucleocapsids are translocated into the cytoplasm for subsequent tegumentation and maturation. The EBV BGLF4 kinase, which induces partial disassembly of the nuclear lamina, and the nuclear egress complex BFRF1/BFLF2 coordinately facilitate the nuclear egress of nucleocapsids. Here, we demonstrate that within EBV reactivated epithelial cells, viral capsids, tegument proteins, and glycoproteins are clustered in the juxtanuclear concave region, accompanied by redistributed cytoplasmic organelles and the cytoskeleton regulator IQ-domain GTPase-activation protein 1 (IQGAP1), close to the microtubule-organizing center (MTOC). The assembly compartment (AC) structure was diminished in BGLF4-knockdown TW01-EBV cells and BGLF4-knockout bacmid-carrying TW01 cells, suggesting that the formation of AC structure is BGLF4-dependent. Notably, glycoprotein gp350/220 was observed by confocal imaging to be distributed in the perinuclear concave region and surrounded by the endoplasmic reticulum (ER) membrane marker calnexin, indicating that the AC may be located within a globular structure derived from ER membranes, adjacent to the outer nuclear membrane. Moreover, the viral capsid protein BcLF1 and tegument protein BBLF1 were co-localized with IQGAP1 near the cytoplasmic membrane in the late stage of replication. Knockdown of IQGAP1 did not affect the AC formation but decreased virion release from both TW01-EBV and Akata+ cells, suggesting IQGAP1-mediated trafficking regulates EBV virion release. The data presented here show that BGLF4 is required for cytoskeletal rearrangement, coordination with the redistribution of cytoplasmic organelles and IQGAP1 for virus maturation, and subsequent IQGAP1-dependent virion release.IMPORTANCEEBV genome is replicated and encapsidated in the nucleus, and the resultant nucleocapsids are translocated to the cytoplasm for subsequent virion maturation. We show that a cytoplasmic AC, containing viral proteins, markers of the endoplasmic reticulum, Golgi, and endosomes, is formed in the juxtanuclear region of epithelial and B cells during EBV reactivation. The viral BGLF4 kinase contributes to the formation of the AC. The cellular protein IQGAP1 is also recruited to the AC and partially co-localizes with the virus capsid protein BcLF1 and tegument protein BBLF1 in EBV-reactivated cells, dependent on the BGLF4-induced cytoskeletal rearrangement. In addition, virion release was attenuated in IQGAP1-knockdown epithelial and B cells after reactivation, suggesting that IQGAP1-mediated trafficking may regulate the efficiency of virus maturation and release.


Assuntos
Citoplasma , Herpesvirus Humano 4 , Proteínas Serina-Treonina Quinases , Proteínas Virais , Vírion , Montagem de Vírus , Liberação de Vírus , Proteínas Ativadoras de ras GTPase , Humanos , Proteínas do Capsídeo/metabolismo , Citoplasma/metabolismo , Citoplasma/virologia , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/química , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/crescimento & desenvolvimento , Herpesvirus Humano 4/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Ativadoras de ras GTPase/metabolismo , Proteínas Virais/metabolismo , Vírion/química , Vírion/crescimento & desenvolvimento , Vírion/metabolismo , Montagem de Vírus/fisiologia , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Complexo de Golgi/metabolismo
4.
Nature ; 567(7748): E13, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30837740

RESUMO

In this Letter, in "About 75% of this reduction is expected to come from emission reductions and the remaining 25% from land use, land-use change and forestry", '25%' should read '1%' and '75%' should read '99%'. In the sentence "The carbon-sink-maximizing portfolio has a small negative effect on annual precipitation (-2 mm) and no effect on air temperature (Table 1)" the word 'precipitation' was omitted. Denmark was accidentally deleted during the conversion of Fig. 1. The original Letter has been corrected online.

5.
PLoS Genet ; 18(9): e1010426, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36155646

RESUMO

Nucleotide excision repair is the primary repair mechanism that removes UV-induced DNA lesions in placentals. Unrepaired UV-induced lesions could result in mutations during DNA replication. Although the mutagenesis of pyrimidine dimers is reasonably well understood, the direct effects of replication fork progression on nucleotide excision repair are yet to be clarified. Here, we applied Damage-seq and XR-seq techniques and generated replication maps in synchronized UV-treated HeLa cells. The results suggest that ongoing replication stimulates local repair in both early and late replication domains. Additionally, it was revealed that lesions on lagging strand templates are repaired slower in late replication domains, which is probably due to the imbalanced sequence context. Asymmetric relative repair is in line with the strand bias of melanoma mutations, suggesting a role of exogenous damage, repair, and replication in mutational strand asymmetry.


Assuntos
Dímeros de Pirimidina , Raios Ultravioleta , DNA/genética , Dano ao DNA/genética , Reparo do DNA/genética , Replicação do DNA/genética , Células HeLa , Humanos , Dímeros de Pirimidina/genética , Raios Ultravioleta/efeitos adversos
6.
Am J Epidemiol ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825331

RESUMO

The aim of the present study was to investigate if use of antidepressants is related to the risk of developing lower (WHO grade 2-3) and higher grade (WHO grade 4) glioma. A registry-based case-control study was performed using 1283 glioma cases and 6400 age-, sex- and geographically matched controls, diagnosed in Sweden 2009-2013. Conditional logistic regression was used to analyze whether Selective Serotonin Reuptake Inhibitors (SSRIs) or non-SSRIs were associated with the risk of developing lower- or higher-grade glioma in the study population. Our results show that use of antidepressant medication was not associated with the risk of developing glioma. We also performed a meta-analysis in which the dataset from the present study was combined with results from two previous epidemiological studies to answer the same questions. The meta-analysis showed a modest risk reduction of developing glioma in relation to antidepressant treatment (OR 0.90 [95% CI 0.83-0.97]), when all glioma subgroups and all forms of antidepressant medications were combined. In conclusion, it remains possible that antidepressants may have common monoaminergic mechanism(s) that reduce the risk of developing glioma.

7.
Small ; 20(8): e2307547, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37814367

RESUMO

The sluggish four-electron oxygen evolving reaction is one of the key limitations of photoelectrochemical water decomposition. Optimizing the binding of active sites to oxygen in water and promoting the conversion of *O to *OOH are the key to enhancing oxygen evolution reaction. In this work, W-doped Cu2 V2 O7 (CVO) constructs corner-sharing tetrahedrally coordinated W-V dual active sites to induce the generation of electron deficiency active centers, promote the adsorption of ─OH, and accelerate the transformation of *O to *OOH for water splitting. The photocurrent obtained by the W-modified CVO photoanode is 0.97 mA cm-2 at 1.23 V versus RHE, which is much superior to that of the reported CVO. Experimental and theoretical results show that the excellent catalytic performance may be attributed to the formation of synergistic dual active sites between W and V atoms, and the introduction of W ions reduces the charge migration distance and prolongs the lifetime of photogenerated carriers. Meanwhile, the electronic structure in the center of the d-band is modulated, which leads to the redistribution of the electron density in CVO and lowers the energy barrier for the conversion of the rate-limiting step *O to *OOH.

8.
Pharmacol Res ; 200: 107075, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38228255

RESUMO

Claudin-5 (CLDN5) is an essential component of tight junctions (TJs) and is critical for the integrity of the blood-brain barrier (BBB), ensuring homeostasis and protection from damage to the central nervous system (CNS). Currently, many researchers have summarized the role and mechanisms of CLDN5 in CNS diseases. However, it is noteworthy that CLDN5 also plays a significant role in tumor growth and metastasis. In addition, abnormal CLDN5 expression is involved in the development of respiratory diseases, intestinal diseases, cardiac diseases, and diabetic ocular complications. This paper aims to review the structure, expression, and regulation of CLDN5, focusing on its role in tumors, including its expression and regulation, effects on malignant phenotypes, and clinical significance. Furthermore, this paper will provide an overview of the role and mechanisms of CLDN5 in respiratory diseases, intestinal diseases, cardiac diseases, and diabetic ocular complications.


Assuntos
Doenças do Sistema Nervoso Central , Diabetes Mellitus , Cardiopatias , Enteropatias , Neoplasias , Humanos , Claudina-5/genética , Claudina-5/metabolismo , Neoplasias/genética
9.
Int J Behav Nutr Phys Act ; 21(1): 9, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38279175

RESUMO

BACKGROUND: Tracking combinations of lifestyle behaviours during childhood ("lifestyle pattern trajectories") can identify subgroups of children that might benefit from lifestyle interventions aiming to improve health outcomes later in life. However, studies on the critical transition period from early to middle childhood are limited. We aimed to describe lifestyle patterns trajectories in children from 2 to 8 years of age and evaluated their associations with cardiometabolic risk markers at age 8 years in a multi-ethnic Asian cohort. METHODS: Twelve lifestyle behaviours related to child's diet, physical activity, screen use, and sleep were ascertained using questionnaires at ages 2, 5, and 8 years. Age-specific lifestyle patterns were derived using principal component analysis and trajectories were determined using group-based multi-trajectory modelling. Child cardiometabolic risk markers were assessed at age 8 years, and associations with trajectories examined using multiple regression, adjusted for confounders. RESULTS: Among 546 children, two lifestyle patterns "healthy" and "unhealthy" were observed at ages 2, 5, and 8 years separately. Three trajectory groups from 2 to 8 years were identified: consistently healthy (11%), consistently unhealthy (18%), and mixed pattern (71%). Children in the consistently unhealthy group (vs. mixed pattern) had increased odds of pre-hypertension (OR = 2.96 [95% CI 1.18-7.41]) and higher levels of diastolic blood pressure (ß = 1.91 [0.27-3.55] mmHg), homeostasis model assessment of insulin resistance (ß = 0.43 [0.13-0.74]), triglycerides (ß = 0.11 [0.00-0.22] mmol/L), and metabolic syndrome score (ß = 0.85 [0.20-1.49]), but not with BMI z-score or any anthropometric measurements. The consistently healthy group showed no differences in cardiometabolic outcomes compared to the mixed pattern group. CONCLUSION: Three distinct lifestyle pattern trajectories were identified from early to middle childhood. Children in the consistently unhealthy lifestyle group did not have a raised BMI but was associated with several elevated cardiometabolic risk markers. These findings suggest the potential benefits of initiating holistic lifestyle interventions to improve children's health and well-being from an early age. TRIAL REGISTRATION: Trial registration number: NCT01174875. Name of registry: ClinicalTrials.gov. URL of registry: https://classic. CLINICALTRIALS: gov/ct2/show/NCT01174875 . Date of registration: August 4, 2010. Date of enrolment of the first participant to the trial: June 2009.


Assuntos
Doenças Cardiovasculares , Estilo de Vida , Criança , Humanos , Índice de Massa Corporal , Dieta , Inquéritos e Questionários , Biomarcadores , Doenças Cardiovasculares/epidemiologia
10.
Inorg Chem ; 63(13): 5924-5930, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38511934

RESUMO

A transition-metal oxide of PbCu3Mn4O12 was prepared at 1523 K and 10 GPa. An A-site-ordered quadruple perovskite structure with the space group Im3̅ is assigned for this compound. Based on bond-valence-sum calculations and X-ray absorption spectroscopy, the charge combination is determined to be PbCu32+Mn44+O12. Due to Cu2+(↑)-Mn4+(↓) antiferromagnetic coupling, a near-room-temperature ferrimagnetic phase transition is observed at approximately 287 K. PbCu3Mn4O12 exhibits a semiconducting electric transport property with the energy band gap Eg ≈ 0.2 eV. In addition, considerable low-field magnetoresistance effects are observed at lower temperatures. This study provides an intrinsic near-room-temperature ferrimagnetic semiconductor that exhibits potential applications in next-generation spintronic devices.

11.
Bioorg Chem ; 148: 107495, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38805850

RESUMO

Targeting Ribonuclease H (RNase H) has been considered a viable strategy for HIV therapy. In this study, a series of novel thiazolo[3, 2-a]pyrimidine derivatives were firstly designed and synthesized as potential inhibitors of HIV-1 RNase H. Among these compounds, A28 exhibited the most potent inhibition against HIV-1 RNase H with an IC50 value of 4.14 µM, which was about 5-fold increase in potency than the hit compound A1 (IC50 = 21.49 µM). To gain deeper insights into the structure-activity relationship (SAR), a CoMFA model was constructed to yield reasonable statistical results (q2 = 0.658 and R2 = 0.969). Results from magnesium ion chelation experiments and molecular docking studies revealed that these thiazolopyrimidine inhibitors may exert their inhibitory activity by binding to an allosteric site on RNase H at the interface between subunits p51 and p66. Furthermore, this analog demonstrated favorable physicochemical properties. Our findings provide valuable groundwork for further development of allosteric inhibitors targeting HIV-1 RNase H.


Assuntos
Desenho de Fármacos , HIV-1 , Simulação de Acoplamento Molecular , Pirimidinas , Relação Estrutura-Atividade , Pirimidinas/química , Pirimidinas/farmacologia , Pirimidinas/síntese química , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , Humanos , Tiazóis/química , Tiazóis/farmacologia , Tiazóis/síntese química , Estrutura Molecular , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Ribonuclease H/antagonistas & inibidores , Ribonuclease H/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Ribonuclease H do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Ribonuclease H do Vírus da Imunodeficiência Humana/metabolismo
12.
Nature ; 562(7726): 259-262, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30305744

RESUMO

The Paris Agreement promotes forest management as a pathway towards halting climate warming through the reduction of carbon dioxide (CO2) emissions1. However, the climate benefits from carbon sequestration through forest management may be reinforced, counteracted or even offset by concurrent management-induced changes in surface albedo, land-surface roughness, emissions of biogenic volatile organic compounds, transpiration and sensible heat flux2-4. Consequently, forest management could offset CO2 emissions without halting global temperature rise. It therefore remains to be confirmed whether commonly proposed sustainable European forest-management portfolios would comply with the Paris Agreement-that is, whether they can reduce the growth rate of atmospheric CO2, reduce the radiative imbalance at the top of the atmosphere, and neither increase the near-surface air temperature nor decrease precipitation by the end of the twenty-first century. Here we show that the portfolio made up of management systems that locally maximize the carbon sink through carbon sequestration, wood use and product and energy substitution reduces the growth rate of atmospheric CO2, but does not meet any of the other criteria. The portfolios that maximize the carbon sink or forest albedo pass only one-different in each case-criterion. Managing the European forests with the objective of reducing near-surface air temperature, on the other hand, will also reduce the atmospheric CO2 growth rate, thus meeting two of the four criteria. Trade-off are thus unavoidable when using European forests to meet climate objectives. Furthermore, our results demonstrate that if present-day forest cover is sustained, the additional climate benefits achieved through forest management would be modest and local, rather than global. On the basis of these findings, we argue that Europe should not rely on forest management to mitigate climate change. The modest climate effects from changes in forest management imply, however, that if adaptation to future climate were to require large-scale changes in species composition and silvicultural systems over Europe5,6, the forests could be adapted to climate change with neither positive nor negative  climate effects.


Assuntos
Sequestro de Carbono , Agricultura Florestal , Florestas , Aquecimento Global/legislação & jurisprudência , Aquecimento Global/prevenção & controle , Objetivos , Desenvolvimento Sustentável/legislação & jurisprudência , Ar , Atmosfera/química , Dióxido de Carbono/análise , Europa (Continente) , Mapeamento Geográfico , Cooperação Internacional , Temperatura
13.
Dermatology ; 240(1): 77-84, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37666213

RESUMO

BACKGROUND: We see increasing evidence that dietary and nutrients factors play a pivotal role in allergic diseases and recent global findings suggest that dietary habits influence the pathogenesis of atopic dermatitis (AD). Frequent consumption of fast food diets is associated with AD development. Despite the rising prevalence of AD in Asia, efforts in investigating the role of dietary habits and AD in adults are still lacking. METHODS: We evaluated the association between the dietary intake of 16 food types and AD manifestations using our Singapore/Malaysia Cross-sectional Genetics Epidemiology Study (SMCGES) population. Dietary habits profiles of 11,494 young Chinese adults (1,550 AD cases/2,978 non-atopic controls/6,386 atopic controls) were assessed by an investigator-administered questionnaire. AD cases were further evaluated for their chronicity (550 chronic) and severity (628 moderate-to-severe). Additionally, we derived a novel food index, Quality of Diet based on Glycaemic Index Score (QDGIS), to examine the association between dietary intake of glycaemic index (GI) and various AD phenotypes. RESULTS: The majority of AD subjects are distributed in the good (37.1%) and moderate (36.2%) QDGIS classes. From the multivariable analyses for age and gender, a moderate QDGIS class was significantly associated with a lower odds of AD (adjusted odds ratio (AOR): 0.844; 95% confidence interval (CI): 0.719-0.991; p < 0.05) and moderate-to-severe AD (AOR: 0.839; 95% CI: 0.714-0.985; p < 0.05). A good QDGIS class was only significantly associated with a lower odds of chronic AD (AOR: 0.769; 95% CI: 0.606-0.976; p < 0.05). Among high GI foods, frequent consumption of burgers/fast food was strongly associated with an increased risk of chronic and moderate-to-severe AD. Among low GI foods, increased intake frequencies of fruits, vegetables, and pulses decreased the odds of AD. Finally, we identified significant associations between frequent seafood, margarine, butter, and pasta consumption with an increased odds of AD despite them having little GI values. CONCLUSION: While genetic components are well-established in their risks associated with increased AD prevalence, there is still a lack of a focus epidemiology study associating dietary influence with AD. Based on the first allergic epidemiology study conducted here in Singapore and Malaysia, it laid the groundwork to guide potential dietary interventions from changing personal dietary habits.


Assuntos
Dermatite Atópica , Hipersensibilidade , Adulto , Humanos , Dermatite Atópica/epidemiologia , Dermatite Atópica/etiologia , Estudos Transversais , Fast Foods , Malásia , Singapura/epidemiologia , Hipersensibilidade/etiologia , Comportamento Alimentar , China
14.
Appl Microbiol Biotechnol ; 108(1): 242, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416210

RESUMO

Flavivirus virus-like particles (VLPs) exhibit a striking structural resemblance to viral particles, making them highly adaptable for various applications, including vaccines and diagnostics. Consequently, increasing VLPs production is important and can be achieved by optimizing expression plasmids and cell culture conditions. While attempting to express genotype III (GIII) Japanese encephalitis virus (JEV) VLPs containing the G104H mutation in the envelope (E) protein, we failed to generate VLPs in COS-1 cells. However, VLPs production was restored by cultivating plasmid-transfected cells at a lower temperature, specifically 28 °C. Furthermore, we observed that the enhancement in JEV VLPs production was independent of amino acid mutations in the E protein. The optimal condition for JEV VLPs production in plasmid-transfected COS-1 cells consisted of an initial culture at 37 °C for 6 h, followed by a shift to 28 °C (37/28 °C) for cultivation. Under 37/28 °C cultivation conditions, flavivirus VLPs production significantly increased in various mammalian cell lines regardless of whether its expression was transiently transfected or clonally selected cells. Remarkably, clonally selected cell lines expressing flavivirus VLPs consistently achieved yields exceeding 1 µg/ml. Binding affinity analyses using monoclonal antibodies revealed similar binding patterns for VLPs of genotype I (GI) JEV, GIII JEV, West Nile virus (WNV), and dengue virus serotype 2 (DENV-2) produced under both 37 °C or 37/28 °C cultivation conditions. In summary, our study demonstrated that the production of flavivirus VLPs can be significantly improved under 37/28 °C cultivation conditions without affecting the conformational structure of the E protein. KEYPOINTS: • Low-temperature culture (37/28 °C) enhances production of flavivirus VLPs. • Flavivirus VLPs consistently achieved yields exceeding 1 µg/ml. • 37/28 °C cultivation did not alter the structure of flavivirus VLPs.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Flavivirus , Chlorocebus aethiops , Animais , Flavivirus/genética , Temperatura , Vírus da Encefalite Japonesa (Espécie)/genética , Temperatura Baixa , Células COS , Mamíferos
15.
Cochrane Database Syst Rev ; 1: CD013474, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38174814

RESUMO

BACKGROUND: Chronic lymphocytic leukaemia (CLL) is the most common lymphoproliferative disease in adults and currently remains incurable. As the progression-free period shortens after each successive treatment, strategies such as maintenance therapy are needed to improve the degree and duration of response to previous therapies. Monoclonal antibodies, immunomodulatory agents, and targeted therapies are among the available options for maintenance therapy. People with CLL who achieve remission after previous therapy may choose to undergo medical observation or maintenance therapy to deepen the response. Even though there is widespread use of therapeutic maintenance agents, the benefits and harms of these treatments are still uncertain. OBJECTIVES: To assess the effects and safety of maintenance therapy, including anti-CD20 monoclonal antibody, immunomodulatory drug therapy, anti-CD52 monoclonal antibody, Bruton tyrosine kinase inhibitor, and B-cell lymphoma-2 tyrosine kinase inhibitor, for individuals with CLL. SEARCH METHODS: We conducted a comprehensive literature search for randomised controlled trials (RCTs) with no language or publication status restrictions. We searched CENTRAL, MEDLINE, Embase, and three trials registers in January 2022 together with reference checking, citation searching, and contact with study authors to identify additional studies. SELECTION CRITERIA: We included RCTs with prospective identification of participants. We excluded cluster-randomised trials, cross-over trial designs, and non-randomised studies. We included studies comparing maintenance therapies with placebo/observation or head-to-head comparisons. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. We assessed risk of bias in the included studies using Cochrane's RoB 1 tool for RCTs. We rated the certainty of evidence for the following outcomes using the GRADE approach: overall survival (OS), health-related quality of life (HRQoL), grade 3 and 4 adverse events (AEs), progression-free survival (PFS), treatment-related mortality (TRM), treatment discontinuation (TD), and all adverse events (AEs). MAIN RESULTS: We identified 11 RCTs (2393 participants) that met the inclusion criteria, including seven trials comparing anti-CD20 monoclonal antibodies (mAbs) (rituximab or ofatumumab) with observation in 1679 participants; three trials comparing immunomodulatory drug (lenalidomide) with placebo/observation in 693 participants; and one trial comparing anti-CD 52 mAbs (alemtuzumab) with observation in 21 participants. No comparisons of novel small molecular inhibitors were found. The median age of participants was 54.1 to 71.7 years; 59.5% were males. The type of previous induction treatment, severity of disease, and baseline stage varied among the studies. Five trials included early-stage symptomatic patients, and three trials included advanced-stage patients (Rai stage III/IV or Binet stage B/C). Six trials reported a frequent occurrence of cytogenic aberrations at baseline (69.7% to 80.1%). The median follow-up duration was 12.4 to 73 months. The risk of selection bias in the included studies was unclear. We assessed overall risk of performance bias and detection bias as low risk for objective outcomes and high risk for subjective outcomes. Overall risk of attrition bias, reporting bias, and other bias was low. Anti-CD20 monoclonal antibodies (mAbs): rituximab or ofatumumab maintenance versus observation Anti-CD20 mAbs maintenance likely results in little to no difference in OS (hazard ratio (HR) 0.94, 95% confidence interval (CI) 0.73 to 1.20; 1152 participants; 3 studies; moderate-certainty evidence) and likely increases PFS significantly (HR 0.61, 95% CI 0.50 to 0.73; 1255 participants; 5 studies; moderate-certainty evidence) compared to observation alone. Anti-CD20 mAbs may result in: an increase in grade 3/4 AEs (rate ratio 1.34, 95% CI 1.06 to 1.71; 1284 participants; 5 studies; low-certainty evidence); little to no difference in TRM (risk ratio 0.82, 95% CI 0.39 to 1.71; 1189 participants; 4 studies; low-certainty evidence); a slight reduction to no difference in TD (risk ratio 0.93, 95% CI 0.72 to 1.20; 1321 participants; 6 studies; low-certainty evidence); and an increase in all AEs (rate ratio 1.23, 95% CI 1.03 to 1.47; 1321 participants; 6 studies; low-certainty evidence) compared to the observation group. One RCT reported that there may be no difference in HRQoL between the anti-CD20 mAbs (ofatumumab) maintenance and the observation group (mean difference -1.70, 95% CI -8.59 to 5.19; 480 participants; 1 study; low-certainty evidence). Immunomodulatory drug (IMiD): lenalidomide maintenance versus placebo/observation IMiD maintenance therapy likely results in little to no difference in OS (HR 0.91, 95% CI 0.61 to 1.35; 461 participants; 3 studies; moderate-certainty evidence) and likely results in a large increase in PFS (HR 0.37, 95% CI 0.19 to 0.73; 461 participants; 3 studies; moderate-certainty evidence) compared to placebo/observation. Regarding harms, IMiD maintenance therapy may result in an increase in grade 3/4 AEs (rate ratio 1.82, 95% CI 1.38 to 2.38; 400 participants; 2 studies; low-certainty evidence) and may result in a slight increase in TRM (risk ratio 1.22, 95% CI 0.35 to 4.29; 458 participants; 3 studies; low-certainty evidence) compared to placebo/observation. The evidence for the effect on TD compared to placebo is very uncertain (risk ratio 0.71, 95% CI 0.47 to 1.05; 400 participants; 2 studies; very low-certainty evidence). IMiD maintenance therapy probably increases all AEs slightly (rate ratio 1.41, 95% CI 1.28 to 1.54; 458 participants; 3 studies; moderate-certainty evidence) compared to placebo/observation. No studies assessed HRQoL. Anti-CD52 monoclonal antibodies (mAbs): alemtuzumab maintenance versus observation Maintenance with alemtuzumab may have little to no effect on PFS, but the evidence is very uncertain (HR 0.55, 95% CI 0.32 to 0.95; 21 participants; 1 study; very low-certainty evidence). We did not identify any study reporting the outcomes OS, HRQoL, grade 3/4 AEs, TRM, TD, or all AEs. AUTHORS' CONCLUSIONS: There is currently moderate- to very low-certainty evidence available regarding the benefits and harms of maintenance therapy in people with CLL. Anti-CD20 mAbs maintenance improved PFS, but also increased grade 3/4 AEs and all AEs. IMiD maintenance had a large effect on PFS, but also increased grade 3/4 AEs. However, none of the above-mentioned maintenance interventions show differences in OS between the maintenance and control groups. The effects of alemtuzumab maintenance are uncertain, coupled with a warning for drug-related infectious toxicity. We found no studies evaluating other novel maintenance interventions, such as B-cell receptor inhibitors, B-cell leukaemia-2/lymphoma-2 inhibitors, or obinutuzumab.


Assuntos
Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Alemtuzumab , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/efeitos adversos , Lenalidomida/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Rituximab/efeitos adversos
16.
PLoS Genet ; 17(11): e1009932, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34843464

RESUMO

Organisms adapt to environmental changes in order to survive. Mothers exposed to nutritional stresses can induce an adaptive response in their offspring. However, the molecular mechanisms behind such inheritable links are not clear. Here we report that in Drosophila, starvation of mothers primes the progeny against subsequent nutritional stress. We found that RpL10Ab represses TOR pathway activity by genetically interacting with TOR pathway components TSC2 and Rheb. In addition, starved mothers produce offspring with lower levels of RpL10Ab in the germline, which results in higher TOR pathway activity, conferring greater resistance to starvation-induced oocyte loss. The RpL10Ab locus encodes for the RpL10Ab mRNA and a stable intronic sequence RNA (sisR-8), which collectively repress RpL10Ab pre-mRNA splicing in a negative feedback mechanism. During starvation, an increase in maternally deposited RpL10Ab and sisR-8 transcripts leads to the reduction of RpL10Ab expression in the offspring. Our study suggests that the maternally deposited RpL10Ab and sisR-8 transcripts trigger a negative feedback loop that mediates intergenerational adaptation to nutritional stress as a starvation response.


Assuntos
Inanição/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Germinativas/crescimento & desenvolvimento , Íntrons/genética , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Transdução de Sinais/genética
17.
Reprod Domest Anim ; 59(4): e14554, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566374

RESUMO

High sperm cryotolerance is crucial to the successful cryopreservation of boar sperm. Evaluating the cryotolerance of boar sperm by using a rapid and convenient technique can enhance the commercial viability of these sperm. This study investigated the correlation between sperm parameters for three sample subsets-fresh sperm, sperm with H2O2-induced oxidative damage (hereinafter referred to as H2O2-induced sperm), and frozen-thawed sperm-to identify the potential of these correlations to predict cryotolerance. A total of 64 sperm samples were obtained from 64 Duroc boars. The sperm parameters of the three subsets, where the frozen-thawed sperm were analysed at 30 or 180 min after thawing, were determined, and the coefficients of correlation between these parameters were calculated. The results indicated that H2O2-induced oxidative stress resulted in decreases in various sperm parameters-including total motility (TM), viability (VIA), mitochondrial membrane potential (MMP), and live sperm with MMP (LMP)-but increased their coefficients of variation. Receiver operating characteristic (ROC) curve analysis revealed that the kinematic parameters of the H2O2-induced sperm effectively predicted those of the frozen-thawed boar sperm at 30 min after thawing; the corresponding area under the ROC curve (AUC) was 0.8667 for TM and 0.8733 for progressive motility in the H2O2-induced sperm. For measurement at 180 min after thawing, the sperm membrane and mitochondrial parameters of the H2O2-induced sperm effectively predicted the LMP of the frozen-thawed boar sperm; the corresponding AUC was 0.8489 for VIA, 0.8289 for MMP, and 0.8444 for LMP. To our knowledge, this is the first study to directly establish a strong correlation between post-thaw boar sperm quality and H2O2-induced oxidative stress before freezing. Our proposed technique can serve as a valuable reference for the development of practical applications aimed at enhancing techniques for cryopreserving boar sperm.


Assuntos
Antioxidantes , Preservação do Sêmen , Suínos , Masculino , Animais , Antioxidantes/farmacologia , Sêmen , Peróxido de Hidrogênio/farmacologia , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides , Criopreservação/veterinária , Criopreservação/métodos , Motilidade dos Espermatozoides
18.
Arch Orthop Trauma Surg ; 144(5): 1889-1900, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38436716

RESUMO

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: There is some controversy about the effects of calcitonin (CT) on lumbar spinal stenosis (LSS). This systematic review and meta-analysis is to assess the strength of the evidence supporting the use of CT in the treatment of patients with LSS. MATERIAL AND METHOD: We performed an electronic search depicting randomized controlled trials (RCTs) through 4 databases from the date of database creation to January 2023. 3 different researchers conducted independent literature screening, data extractions, and quality assessments. The outcome measures included visual analogue scale (VAS), walking distance, and oswestry disability index (ODI). Meta-analysis and trial sequence analysis (TSA) were carried out using RevMan 5.4, Stata 16.0, and TSA 0.9. GRADE 3.6 was used to evaluate the evidence quality. RESULTS: We accepted 9 studies with 496 participants. The meta-analysis revealed that CT offered no significant improvement in VAS, walking distance, or ODI in patients with LSS. CONCLUSION: There is no evidence that CT has a benefit in patients with LSS, either alone or in combination with other treatments, or depending on the route of administration, according to the systematic review and meta-analysis of relevant RCTs.


Assuntos
Calcitonina , Vértebras Lombares , Estenose Espinal , Humanos , Conservadores da Densidade Óssea/uso terapêutico , Calcitonina/uso terapêutico , Avaliação da Deficiência , Vértebras Lombares/diagnóstico por imagem , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Estenose Espinal/tratamento farmacológico
19.
Environ Monit Assess ; 196(3): 246, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329592

RESUMO

An integrated, remotely sensed approach to assess land-use and land-cover change (LULCC) dynamics plays an important role in environmental monitoring, management, and policy development. In this study, we utilized the advantage of land-cover seasonality, canopy height, and spectral characteristics to develop a phenology-based classification model (PCM) for mapping the annual LULCC in our study areas. Monthly analysis of normalized difference vegetation index (NDVI) and near-infrared (NIR) values derived from SPOT images enabled the detection of temporal characteristics of each land type, serving as crucial indices for land type classification. The integration of normalized difference built-up index (NDBI) derived from Landsat images and airborne LiDAR canopy height into the PCM resulted in an overall performance of 0.85, slightly surpassing that of random forest analysis or principal component analysis. The development of PCM can reduce the time and effort required for manual classification and capture annual LULCC changes among five major land types: forests, built-up land, inland water, agriculture land, and grassland/shrubs. The gross change LULCC analysis for the Taoyuan Tableland demonstrated fluctuations in land types over the study period (2013 to 2022). A negative correlation (r = - 0.79) in area changes between grassland/shrubs and agricultural land and a positive correlation (r = 0.47) between irrigation ponds and agricultural land were found. Event-based LULCC analysis for Taipei City demonstrated a balance between urbanization and urban greening, with the number of urbanization events becoming comparable to urban greening events when the spatial extent of LULCC events exceeds 1000 m2. Besides, small-scale urban greening events are frequently discovered and distributed throughout the metropolitan area of Taipei City, emphasizing the localized nature of urban greening events.


Assuntos
Monitoramento Ambiental , Tecnologia de Sensoriamento Remoto , Agricultura , Formulação de Políticas , Lagoas
20.
Plant J ; 111(4): 1069-1080, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35727866

RESUMO

Genetic compensation has been proposed to explain phenotypic differences between gene knockouts and knockdowns in several metazoan and plant model systems. With the rapid development of reverse genetic tools such as CRISPR/Cas9 and RNAi in microalgae, it is increasingly important to assess whether genetic compensation affects the phenotype of engineered algal mutants. While exploring triacylglycerol (TAG) biosynthesis pathways in the model alga Chlamydomonas reinhardtii, it was discovered that knockout of certain genes catalyzing rate-limiting steps of TAG biosynthesis, type-2 diacylglycerol acyltransferase genes (DGTTs), triggered genetic compensation under abiotic stress conditions. Genetic compensation of a DGTT1 null mutation by a related PDAT gene was observed regardless of the strain background or mutagenesis approach, for example, CRISPR/Cas 9 or insertional mutagenesis. However, no compensation was found in the PDAT knockout mutant. The effect of PDAT knockout was evaluated in a Δvtc1 mutant, in which PDAT was upregulated under stress, resulting in a 90% increase in TAG content. Knockout of PDAT in the Δvtc1 background induced a 12.8-fold upregulation of DGTT1 and a 272.3% increase in TAG content in Δvtc1/pdat1 cells, while remaining viable. These data suggest that genetic compensation contributes to the genetic robustness of microalgal TAG biosynthetic pathways, maintaining lipid and redox homeostasis in the knockout mutants under abiotic stress. This work demonstrates examples of genetic compensation in microalgae, implies the physiological relevance of genetic compensation in TAG biosynthesis under stress, and provides guidance for future genetic engineering and mutant characterization efforts.


Assuntos
Chlamydomonas reinhardtii , Microalgas , Animais , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , Diacilglicerol O-Aciltransferase/genética , Microalgas/genética , Microalgas/metabolismo , Plantas/metabolismo , Triglicerídeos/metabolismo
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