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2.
RNA ; 27(11): 1374-1389, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34429367

RESUMO

Toxin-antitoxin (TA) systems are genetic modules composed of a toxin interfering with cellular processes and its cognate antitoxin, which counteracts the activity of the toxin. TA modules are widespread in bacterial and archaeal genomes. It has been suggested that TA modules participate in the adaptation of prokaryotes to unfavorable conditions. The Bosea sp. PAMC 26642 used in this study was isolated from the Arctic lichen Stereocaulon sp. There are 12 putative type II TA loci in the genome of Bosea sp. PAMC 26642. Of these, nine functional TA systems have been shown to be toxic in Escherichia coli The toxin inhibits growth, but this inhibition is reversed when the cognate antitoxin genes are coexpressed, indicating that these putative TA loci were bona fide TA modules. Only the BoVapC1 (AXW83_01405) toxin, a homolog of VapC, showed growth inhibition specific to low temperatures, which was recovered by the coexpression of BoVapB1 (AXW83_01400). Microscopic observation and growth monitoring revealed that the BoVapC1 toxin had bacteriostatic effects on the growth of E. coli and induced morphological changes. Quantitative real time polymerase chain reaction and northern blotting analyses showed that the BoVapC1 toxin had a ribonuclease activity on the initiator tRNAfMet, implying that degradation of tRNAfMet might trigger growth arrest in E. coli Furthermore, the BoVapBC1 system was found to contribute to survival against prolonged exposure at 4°C. This is the first study to identify the function of TA systems in cold adaptation.


Assuntos
Antitoxinas/metabolismo , Toxinas Bacterianas/metabolismo , Bradyrhizobiaceae/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , RNA de Transferência de Metionina/metabolismo , Sistemas Toxina-Antitoxina/genética , Antitoxinas/genética , Proteínas de Bactérias , Toxinas Bacterianas/genética , Bradyrhizobiaceae/genética , Bradyrhizobiaceae/isolamento & purificação , Bradyrhizobiaceae/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Líquens/fisiologia , Óperon , Regiões Promotoras Genéticas
3.
PLoS Pathog ; 17(12): e1010092, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34914812

RESUMO

The development of safe and effective vaccines to prevent SARS-CoV-2 infections remains an urgent priority worldwide. We have used a recombinant vesicular stomatitis virus (rVSV)-based prime-boost immunization strategy to develop an effective COVID-19 vaccine candidate. We have constructed VSV genomes carrying exogenous genes resulting in the production of avirulent rVSV carrying the full-length spike protein (SF), the S1 subunit, or the receptor-binding domain (RBD) plus envelope (E) protein of SARS-CoV-2. Adding the honeybee melittin signal peptide (msp) to the N-terminus enhanced the protein expression, and adding the VSV G protein transmembrane domain and the cytoplasmic tail (Gtc) enhanced protein incorporation into pseudotype VSV. All rVSVs expressed three different forms of SARS-CoV-2 spike proteins, but chimeras with VSV-Gtc demonstrated the highest rVSV-associated expression. In immunized mice, rVSV with chimeric S protein-Gtc derivatives induced the highest level of potent neutralizing antibodies and T cell responses, and rVSV harboring the full-length msp-SF-Gtc proved to be the superior immunogen. More importantly, rVSV-msp-SF-Gtc vaccinated animals were completely protected from a subsequent SARS-CoV-2 challenge. Overall, we have developed an efficient strategy to induce a protective response in SARS-CoV-2 challenged immunized mice. Vaccination with our rVSV-based vector may be an effective solution in the global fight against COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vírus da Estomatite Vesicular Indiana/genética , Enzima de Conversão de Angiotensina 2/genética , Animais , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/genética , Chlorocebus aethiops , Humanos , Imunização , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero , Proteínas Virais/genética , Proteínas Virais/imunologia
4.
Biochem Biophys Res Commun ; 587: 119-125, 2022 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-34871999

RESUMO

Abscisic acid (ABA) plays an important role in seed germination, stomatal closure, and seedling growth inhibition in plants. Among downstream genes whose expression levels are regulated by AFA1 (Arabidopsis F-box Protein Hypersensitive to ABA 1), one gene, AtHAD1 upregulated by ABA was selected from Arabidopsis. AtHAD1 was induced by drought and salt stresses as well as by ABA and was found in dry seeds. Its loss-of-function mutants exhibited increased ABA-sensitivity in germination, seedling growth, and stomatal closure. In addition, the mutants displayed a lower water loss rate and higher survival rate under drought stress than the wild-type plants, indicating that a loss of AtHAD1 leads to enhanced drought tolerance. These results show that AtHAD1 has an inhibitory role in the ABA response and ABA-mediated drought tolerance. The expression levels of several ABA-responsive genes in athad1 were higher than those in the wild-type under the ABA treatment, suggesting that AtHAD1, as a negative regulator in the ABA response, could be associated with the downregulation of the ABA-responsive genes. The phosphatase assay showed that AtHAD1 exhibits phosphatase activity. Monitoring of the subcellular localization of GFP-fused AtHAD1 proteins indicated that AtHAD1 exists in the nucleus and cytoplasm. Overall, this study shows that Arabidopsis HAD1 as an intracellular phosphatase negatively functions in the ABA-mediated cellular responses. This research could serve as a research basis to understand the functional link between ABA signaling and the regulation process of the cellular phosphate level.


Assuntos
Ácido Abscísico/farmacologia , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Hidrolases/genética , Monoéster Fosfórico Hidrolases/genética , Reguladores de Crescimento de Plantas/farmacologia , Ácido Abscísico/metabolismo , Adaptação Fisiológica/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Germinação/efeitos dos fármacos , Germinação/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/genética , Estômatos de Plantas/metabolismo , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Salinidade , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/metabolismo , Sementes/efeitos dos fármacos , Sementes/genética , Sementes/metabolismo , Transdução de Sinais , Estresse Fisiológico
5.
Int J Dent Hyg ; 20(4): 721-731, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35920085

RESUMO

OBJECTIVES: This study aimed to investigate the association between the frequency of SSB consumption and the prevalence of oral symptoms in adolescents. METHODS: We analysed the data collected from the 2017 (13th) Korea Youth Risk Behaviour Web-based Survey (KYRBWS). KYRBS collected beverage consumption data from 64,991 Korean adolescents. Self-reported oral symptoms including sensitivity to food, sharp aches and pains in the teeth, and painful or bleeding gums were also collected. Multivariable logistic regression modelling was used to test the association between the frequency of SSB consumption and oral symptoms groups. RESULTS: It was found that Korean adolescents who consumed SSB at least once a week (94.4%) experienced more subjective oral symptoms (46.5%) even after controlling for confounding variables. In addition, as the frequency of SSB intake in adolescents increased, the subjective oral symptoms increased. CONCLUSIONS: The results of this study clearly revealed that the SSB consumption impacted adolescents' subjective oral symptoms. Compared with those who did not consume SSBs, those who consumed SSBs showed increased for developing subjective oral symptoms.


Assuntos
Saúde Bucal , Bebidas Adoçadas com Açúcar , Adolescente , Humanos , Bebidas , República da Coreia/epidemiologia , Autorrelato
6.
Physiol Plant ; 173(4): 2376-2389, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34687457

RESUMO

ABA is a phytohormone involved in diverse plant events such as seed germination and drought response. An F-box protein functions as a substrate receptor of the SCF complex and is responsible for ubiquitination of target proteins, triggering their subsequent degradation mediated by ubiquitin proteasome system. Here, we have isolated a gene named ARABIDOPSIS F-BOX PROTEIN HYPERSENSITIVE TO ABA 1 (AFA1) that was upregulated by ABA. AFA1 interacted with adaptor proteins of the SCF complex, implying its role as a substrate receptor of the complex. Its loss of function mutants, afa1 seedlings, exhibited ABA-hypersensitivity, including delayed germination in the presence of ABA. Moreover, loss of AFA1 led to increased drought tolerance in adult plants. Microarray data with ABA treatments indicated that 129 and 219 genes were upregulated or downregulated, respectively, by more than three times in afa1 relative to the wild type. Among the upregulated genes in afa1, the expression of 28.7% was induced by more than three times in the presence of ABA, while only 9.3% was repressed to the same extent. These data indicate that AFA1 is involved in the downregulation of many ABA-inducible genes, in accordance with the ABA-hypersensitive phenotype of afa1. Epistasis analysis showed that AFA1 could play a role upstream of ABI4 and ABI5 in the ABA signaling for germination inhibition. Collectively, our findings suggest that AFA1 is a novel F-box protein that negatively regulates ABA signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas F-Box , Ácido Abscísico/farmacologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Secas , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Regulação da Expressão Gênica de Plantas , Germinação , Mutação , Sementes/metabolismo
7.
BMC Health Serv Res ; 21(1): 748, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34315462

RESUMO

BACKGROUND: Professional oral care in the intensive care unit may reduce the incidence of Ventilator Associated Pneumonia, which increases the patient's mortality rate. This study aimed to develop a competency for professional oral hygiene care of endotracheally-intubated intensive-care patients. METHODS: First, we developed a competency draft by reviewing the literature on oral hygiene care of patients in the intensive care unit. Next, we developed expert validity test questionnaires using this draft and conducted expert validity tests twice on 18 experts. We determined competency as a content validity index of 0.8 or more and received expert additive opinions about competency through an open-questionnaire expert validity test paper in this methodology study. RESULTS: The content validity index ranged from 0.8 ~ 1.0 for all items. The competency of 'professionalism' comprised 2 sub-competencies with 7 behavioral indicators. 'POHC preparation' comprised 3 sub-competencies with 10 behavioral indicators. 'POHC implementation' comprised 3 sub-competencies with 6 behavioral indicators. 'POHC evaluation' comprised 2 sub-competencies with 8 behavioral indicators. Lastly 'Cooperation among experts' comprised 3 sub-competencies with 7 behavioral indicatiors. CONCLUSIONS: To provide patients with high quality oral hygiene care, these competencies should be implemented, and oral hygiene care professionals and related medical personnel should form a cooperative system.


Assuntos
Unidades de Terapia Intensiva , Higiene Bucal , Cuidados Críticos , Humanos , Profissionalismo , Inquéritos e Questionários
8.
BMC Oral Health ; 21(1): 233, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33941148

RESUMO

BACKGROUND: This cross-sectional study aimed to examine the relationship between sleep habits and oral disease symptoms in adolescents. METHODS: Among 62,276 adolescents who participated in the 13th Korea Youth Risk Behavior Web-based Survey (2017), we selected a total of 54,766 adolescents (age, 12-18 years; male, 49.9%) for the final analysis, after excluding those who did not report their sleep duration. The 13th Korea Youth Risk Behavior Web-based Survey data were obtained from a stratified, multistage, clustered sample. Independent variables included general characteristics, oral health behavior, sleep types, sleep duration, and sleep quality; dependent variables comprised oral disease symptoms. Sleep was categorized according to bedtime astype A (bedtime < 1 a.m.) and type B (bedtime ≥ 1 a.m.). Data were analyzed using logistic regression analysis. Statistical significance was set at p < 0.05. RESULTS: After adjusting for all covariates, adolescents with type A sleep had a higher risk of toothache on chewing (OR = 1.08, 95% CI 1.02-1.15) than adolescents with type B. Adolescents who slept for 6 h or less each night had a higher risk of pain in the tongue and buccal mucosa (OR = 1.35, 95% CI 1.18-1.54), gingival pain, and bleeding (OR = 1.31, 95% CI 1.19-1.45) than those who slept for more than 8 h. Adolescents with low quality of sleep had a higher risk of toothache or throbbing (OR = 1.70, 95% CI 1.60-1.81), toothache on chewing (OR = 1.73, 95% CI 1.65-1.82), and halitosis (OR = 1.51, 95% CI 1.41-1.59) than those with high quality of sleep. CONCLUSIONS: Our findings indicate that some oral symptoms are related to sleep duration and quality. It is essential to inculcate good sleeping habits in adolescents by emphasizing the effects of inadequate sleep duration and quality.


Assuntos
Assunção de Riscos , Sono , Adolescente , Criança , Estudos Transversais , Humanos , Internet , Masculino , República da Coreia/epidemiologia , Inquéritos e Questionários
9.
Int J Dent Hyg ; 18(3): 307-313, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32196912

RESUMO

OBJECTIVE: High stress levels experienced by medical professionals are a well-established phenomenon in current literature. However, there are few studies focusing on stress experienced in the field of oral health or on the sense of coherence (SOC) that helps to actively respond to job stress. The purpose of this study was to analyse if there is an association between SOC and job stress among dental hygienists in Korea. METHODS: A cross-sectional study was conducted on a convenience sample of 441 dental hygienists in the Seoul Gyeonggi province, Korea. The independent variable was SOC which had three dimensions: comprehensibility, manageability and meaningfulness. The dependent variable was job stress, which was evaluated using the Korean Occupational Stress Scale Short Form. Confounding factors were age, marital status, educational background, type of hospital, and work experience. The chi-square test and t test measures were used for bivariate analysis. Multiple logistic regression analysis was performed to confirm the association between SOC and job stress. The collected data were statistically analysed using SPSS version 22.0. RESULTS: The SOC score showed a significant difference in relation to the job stress score. The SOC score was high when the job stress was low (P < .001). Overall SOC scores showed an inverse correlation with job stress. CONCLUSION: This study reports that a higher SOC is associated with lower job stress in Korean dental hygienists. Since a higher SOC in dental hygienists indicated that they could cope with job stress more positively, it is important to increase their SOC.


Assuntos
Estresse Ocupacional , Senso de Coerência , Estudos Transversais , Higienistas Dentários , Humanos , República da Coreia , Inquéritos e Questionários
10.
J Biol Chem ; 293(47): 18404-18419, 2018 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-30305394

RESUMO

BPI-inducible protein A (BipA) is a conserved ribosome-associated GTPase in bacteria that is structurally similar to other GTPases associated with protein translation, including IF2, EF-Tu, and EF-G. Its binding site on the ribosome appears to overlap those of these translational GTPases. Mutations in the bipA gene cause a variety of phenotypes, including cold and antibiotics sensitivities and decreased pathogenicity, implying that BipA may participate in diverse cellular processes by regulating translation. According to recent studies, a bipA-deletion strain of Escherichia coli displays a ribosome assembly defect at low temperature, suggesting that BipA might be involved in ribosome assembly. To further investigate BipA's role in ribosome biogenesis, here, we compared and analyzed the ribosomal protein compositions of MG1655 WT and bipA-deletion strains at 20 °C. Aberrant 50S ribosomal subunits (i.e. 44S particles) accumulated in the bipA-deletion strain at 20 °C, and the ribosomal protein L6 was absent in these 44S particles. Furthermore, bipA expression was significantly stimulated at 20 °C, suggesting that it encodes a cold shock-inducible GTPase. Moreover, the transcriptional regulator cAMP receptor protein (CRP) positively promoted bipA expression only at 20 °C. Importantly, GFP and α-glucosidase refolding assays revealed that BipA has chaperone activity. Our findings indicate that BipA is a cold shock-inducible GTPase that participates in 50S ribosomal subunit assembly by incorporating the L6 ribosomal protein into the 44S particle during the assembly.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , GTP Fosfo-Hidrolases/metabolismo , Regulação Bacteriana da Expressão Gênica , Chaperonas Moleculares/metabolismo , Fosfoproteínas/metabolismo , Subunidades Ribossômicas Maiores de Bactérias/metabolismo , Temperatura Baixa , Proteína Receptora de AMP Cíclico/genética , Proteína Receptora de AMP Cíclico/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , GTP Fosfo-Hidrolases/genética , Chaperonas Moleculares/genética , Fosfoproteínas/genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Subunidades Ribossômicas Maiores de Bactérias/genética
11.
Am J Orthod Dentofacial Orthop ; 155(3): 355-361, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30826038

RESUMO

INTRODUCTION: This study aimed to evaluate the associations between normative orthodontic treatment need and oral health-related quality of life (OHRQoL) at an item level as well as subscale and total score levels among schoolchildren. METHODS: A cross-sectional study was conducted on 2,010 randomly selected children aged approximately 8, 10, 12, and 15 years residing in the Gyeonggi province, Korea. Children were clinically examined with the Index of Orthodontic Treatment Need (IOTN). To measure OHRQoL, the Child Oral Health Impact Profile (COHIP) was used. RESULTS: In the physical health domain of COHIP, crooked teeth, discoloration, "food sticking," and "difficulty keeping teeth clean" were significantly associated with IOTN levels (P < 0.05), whereas pain, sensitivity and bleeding, bad breath, mouth breathing, and dry mouth were not. In addition, present and future dental health were significantly associated with IOTN levels, although self-confidence, attractiveness, and future health were not. As expected, the 5 subscale scores and total score of COHIP were significantly associated with IOTN levels after adjustment for gender, age, socioeconomic level, and caries state. CONCLUSIONS: This study suggests the importance of in-depth investigation at the item level of OHRQoL assessment scales to better evaluate the impact of malocclusion that might be alleviated by orthodontic treatment.


Assuntos
Índice de Necessidade de Tratamento Ortodôntico , Saúde Bucal , Qualidade de Vida , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino , República da Coreia , Fatores Socioeconômicos
12.
Int J Dent Hyg ; 17(2): 177-182, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30485645

RESUMO

OBJECTIVES: The purpose of the present study was to analyse the effects of working posture, physical balance and work accumulation on shifts in plantar pressure in dental hygienists, by measuring REBA, which evaluates working posture, and plantar pressure, which evaluates physical balance. METHODS: This study was conducted on 24 dental hygienists currently working in dental clinics. The ergonomic assessment method of the Rapid Entire Body Assessment was used to evaluate working posture in the dental hygienists, and a Gait Analyzer was used to measure plantar pressure. RESULTS: The subjects' mean REBA score was 4.96 ± 1.04 points, and 87.5% of the subjects showed poor working posture, with a REBA score of at least four points. Among subjects with a REBA score of four points or more, seven of the eight parts of the sole of the foot showed significant differences in plantar pressure between the right and left feet (P < 0.05). When we examined changes in plantar pressure over a week, pressure increased on the left side, and in particular, for subjects with a REBA score of four points or higher, pressure increased in the left foot and in the anterior right foot. CONCLUSIONS: Most of the dental hygienists in this study showed poor posture during working. Subjects with poor posture at a level requiring intervention showed differences in plantar pressure between the right and left feet. Inappropriate posture can cause musculoskeletal disorders. Therefore, it will be necessary to prepare internal and external measures to maintain proper working posture in dental hygienists, including education, exercise, improvement of the working environment and improvement of ergonomic equipment and devices.


Assuntos
Higienistas Dentários , Ergonomia/métodos , Pé/fisiologia , Pressão , Trabalho/fisiologia , Adulto , Meio Ambiente , Ergonomia/instrumentação , Exercício Físico , Feminino , Educação em Saúde , Humanos , Masculino , Doenças Musculoesqueléticas/etiologia , Doenças Musculoesqueléticas/prevenção & controle , Doenças Profissionais/etiologia , Doenças Profissionais/prevenção & controle , Equilíbrio Postural , Postura , Jornada de Trabalho em Turnos , Adulto Jovem
13.
J Bacteriol ; 198(17): 2284-96, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27297882

RESUMO

UNLABELLED: The unique Escherichia coli GTPase Der (double Era-like GTPase), which contains tandemly repeated GTP-binding domains, has been shown to play an essential role in 50S ribosomal subunit biogenesis. The depletion of Der results in the accumulation of precursors of 50S ribosomal subunits that are structurally unstable at low Mg(2+) concentrations. Der homologs are ubiquitously found in eubacteria. Conversely, very few are conserved in eukaryotes, and none is conserved in archaea. In the present study, to verify their conserved role in bacterial 50S ribosomal subunit biogenesis, we cloned Der homologs from two gammaproteobacteria, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium; two pathogenic bacteria, Staphylococcus aureus and Neisseria gonorrhoeae; and the extremophile Deinococcus radiodurans and then evaluated whether they could functionally complement the E. coli der-null phenotype. Only K. pneumoniae and S Typhimurium Der proteins enabled the E. coli der-null strain to grow under nonpermissive conditions. Sucrose density gradient experiments revealed that the expression of K. pneumoniae and S Typhimurium Der proteins rescued the structural instability of 50S ribosomal subunits, which was caused by E. coli Der depletion. To determine what allows their complementation, we constructed Der chimeras. We found that only Der chimeras harboring both the linker and long C-terminal regions could reverse the growth defects of the der-null strain. Our findings suggest that ubiquitously conserved essential GTPase Der is involved in 50S ribosomal subunit biosynthesis in various bacteria and that the linker and C-terminal regions may participate in species-specific recognition or interaction with the 50S ribosomal subunit. IMPORTANCE: In Escherichia coli, Der (double Era-like GTPase) is an essential GTPase that is important for the production of mature 50S ribosomal subunits. However, to date, its precise role in ribosome biogenesis has not been clarified. In this study, we used five Der homologs from gammaproteobacteria, pathogenic bacteria, and an extremophile to elucidate their conserved function in 50S ribosomal subunit biogenesis. Among them, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium Der homologs implicated the participation of Der in ribosome assembly in E. coli Our results show that the linker and C-terminal regions of Der homologs are correlated with its functional complementation in E. coli der mutants, suggesting that they are involved in species-specific recognition or interaction with 50S ribosomal subunits.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Sequência de Aminoácidos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Evolução Molecular , Proteínas de Ligação ao GTP/genética , Teste de Complementação Genética , Mutação , Especificidade da Espécie
14.
Retrovirology ; 13(1): 82, 2016 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-27894306

RESUMO

BACKGROUND: Vaccination with inactivated (killed) whole-virus particles has been used to prevent a wide range of viral diseases. However, for an HIV vaccine this approach has been largely negated due to inherent safety concerns, despite the ability of killed whole-virus vaccines to generate a strong, predominantly antibody-mediated immune response in vivo. HIV-1 Clade B NL4-3 was genetically modified by deleting the nef and vpu genes and substituting the coding sequence for the Env signal peptide with that of honeybee melittin signal peptide to produce a less virulent and more replication efficient virus. This genetically modified virus (gmHIV-1NL4-3) was inactivated and formulated as a killed whole-HIV vaccine, and then used for a Phase I human clinical trial (Trial Registration: Clinical Trials NCT01546818). The gmHIV-1NL4-3 was propagated in the A3.01 human T cell line followed by virus purification and inactivation with aldrithiol-2 and γ-irradiation. Thirty-three HIV-1 positive volunteers receiving cART were recruited for this observer-blinded, placebo-controlled Phase I human clinical trial to assess the safety and immunogenicity. RESULTS: Genetically modified and killed whole-HIV-1 vaccine, SAV001, was well tolerated with no serious adverse events. HIV-1NL4-3-specific PCR showed neither evidence of vaccine virus replication in the vaccine virus-infected human T lymphocytes in vitro nor in the participating volunteers receiving SAV001 vaccine. Furthermore, SAV001 with adjuvant significantly increased the pre-existing antibody response to HIV-1 proteins. Antibodies in the plasma of vaccinees were also found to recognize HIV-1 envelope protein on the surface of infected cells as well as showing an enhancement of broadly neutralizing antibodies inhibiting tier I and II of HIV-1 B, D, and A subtypes. CONCLUSION: The killed whole-HIV vaccine, SAV001, is safe and triggers anti-HIV immune responses. It remains to be determined through an appropriate trial whether this immune response prevents HIV infection.


Assuntos
Vacinas contra a AIDS , Anticorpos Neutralizantes/sangue , Anticorpos Anti-HIV/sangue , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Imunogenicidade da Vacina , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/efeitos adversos , Vacinas contra a AIDS/imunologia , Adulto , Animais , Anticorpos Neutralizantes/imunologia , Abelhas/genética , Feminino , Produtos do Gene nef/genética , Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , HIV-1/genética , Proteínas do Vírus da Imunodeficiência Humana/genética , Humanos , Masculino , Pessoa de Meia-Idade , Sinais Direcionadores de Proteínas , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Proteínas Virais Reguladoras e Acessórias/genética , Adulto Jovem
15.
Plasmid ; 81: 32-41, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26143370

RESUMO

CspA has been identified as a major cold-shock protein in Escherichia coli. CspA binds to RNAs which are abnormally folded at low temperature and then acts as an RNA chaperone unfolding those RNAs. The dramatic expression of cspA at low temperature is contributed by posttranscriptional stability and robust translatability. Interestingly, when cspA mRNA encoding a premature nonsense codon was overexpressed at low temperature, cell growth was completely inhibited. This phenotype was termed LACE (the low temperature-dependent antibiotic effect of truncated cspA expression), and this lethality resulted from exclusive stalling of most ribosomes on mutant cspA mRNAs. In a previous study, we demonstrated that overexpression of the ATP-dependent DNA helicases, UvrD and DinG, suppressed the lethality and ribosome stalling caused by mutant cspA mRNA. In the present study, we attempted to elucidate how these two DNA helicases help recover normal growth under LACE condition. Interestingly, we found that UvrD and DinG appeared to have an ability to down-regulate the replication of pUC-based high copy plasmid. In plasmid copy number tests, the amount of pUC-based plasmid encoding mutant cspA was reduced by 3-10-fold when either UvrD or DinG was expressed. Through a ß-galactosidase activity assay, we also confirmed that expression of the lacZα gene inserted into the pUC-based plasmid was significantly reduced due to down-regulation of plasmid replication. Our findings imply that UvrD and DinG, known as non-replicative helicases, play a novel role in the regulation of ColE1-like plasmid replication.


Assuntos
Proteínas de Bactérias/genética , DNA Helicases/genética , Replicação do DNA , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Plasmídeos/genética , Clonagem Molecular , DNA Helicases/metabolismo , Ativação Enzimática , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica
16.
Front Mol Biosci ; 10: 1175889, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152896

RESUMO

The BipA protein is a universally conserved GTPase in bacterial species and is structurally similar to translational GTPases. Despite its wide distribution, BipA is dispensable for growth under optimal growth conditions but is required under stress conditions. In particular, bipA-deleted cells (ESC19) have been shown to display a variety of phenotypic changes in ribosome assembly, capsule production, lipopolysaccharide (LPS) synthesis, biofilm formation, and motility at low temperature, suggesting its global regulatory roles in cold adaptation. Here, through genomic library screening, we found a suppressor clone containing nhaR, which encodes a Na+-responsive LysR-type transcriptional regulator and whose gene product partially restored the growth of strain ESC19 at 20°C. The suppressed cells showed slightly reduced capsule production and improved biofilm-forming ability at 20°C, whereas the defects in the LPS core and swimming motility were not restored but aggravated by overexpression of nhaR. Notably, the overexpression partially alleviated the defects in 50S ribosomal subunit assembly and rRNA processing of ESC19 cells by enhancing the overall transcription of rRNA. Electrophoretic mobility shift assay revealed the association of NhaR with the promoter of seven rrn operons, suggesting that NhaR directly regulates rRNA transcription in ESC19 at 20°C. The suppressive effects of NhaR on ribosomes, capsules, and LPS were dependent on its DNA-binding activity, implying that NhaR might be a transcriptional factor involved in regulating these genes at 20°C. Furthermore, we found that BipA may be involved in adaptation to salt stress, designating BipA as a global stress-responsive regulator, as the deletion of bipA led to growth defects at 37°C and high Na+ concentrations without ribosomal defects.

17.
Food Res Int ; 167: 112592, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087202

RESUMO

Signal detection theory (SDT) sensory discrimination analysis using A-Not A with a two-step rating is an efficient approach to in-house sensory quality management in the food industry. For such sensory analysis using an internal panel, the panels' ability to use stable decision criteria and provide a consistent response distribution responding to "A" vs "Not A" is critical for guaranteeing the data quality. This study examined the effects of the familiarization procedure (FP) and reference presentation probability (RPP) in the SDT A-Not A rating protocol on the panels' sensory learning of samples and stability of decision criteria using SDT parameters, recognition d' (d'Rec),criteria location (c), and discrimination d' indices. Three different protocols were compared using ice-tea samples with small differences: Control, 0.25 RPP with repeated reference tasting (FPR); Modified-1, 0.25 RPP with reference categorization (FPC); Modified-2, 0.5 RPP with reference categorization (FPC). An independent sample design with three groups having equal sensitivity was used to identify the differences among the protocols. For each protocol, two sub-groups with similar decision criteria (response bias) were formed according to the results obtained from the pre-test and used for the main-test analysis. SDT analysis results indicated that the Modified-2 protocol with a higher RPP (0.5) induced the most efficient sensory learning of the reference. The protocol improved the subjects' recognition of the reference and test samples, better differentiating from the reference and stabilizing the decision criterion, resulting in higher discrimination performance (larger d'). The results showed that d'Rec analysis, together with d' analysis using a sensory panel, is a useful tool for monitoring the panel performance and checking for the sensory data quality of the sensory difference tests. In the present paper, a detailed illustration of the A-Not A sensory test procedure and examples of how to apply the SDT indices for different business decision-making is also introduced using the design and results of the present experiment.


Assuntos
Análise de Alimentos , Sensação , Humanos , Análise de Alimentos/métodos
18.
Vaccine ; 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37821316

RESUMO

The worldwide health, economic, and societal consequences of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic have been devastating. The primary strategy to prevent new infectious diseases is to vaccinate the majority of people worldwide. However, the significant hurdles that are faced include vaccine safety concerns and vaccine reluctance. Among the various types of vaccines, the recombinant vesicular stomatitis virus (rVSV) is a promising candidate owing to its safety and efficacy. Therefore, we investigated the toxicity, immunogenicity, and local tolerance of the rVSVInd(GML)-mspSGtc vaccine against SARS-CoV-2. New Zealand White (NZW) rabbits were administered single or three repeated intramuscular injections of rVSVInd(GML)-mspSGtc every 2 weeks, followed by a 4-week recovery period. Male and female rabbits were randomly assigned into three groups: a control group and two dose-level groups (1 × 109 and 4 × 109 PFU/mL). Treatment-related changes included a temporary increase in body temperature and local inflammation at the injection site. These findings indicated recovery or a trend toward recovery, with no overt systemic toxicity. Immunogenicity analysis results suggested that rVSVInd(GML)-mspSGtc elicited a robust dose-dependent immune response in terms of neutralizing antibodies and IgG antibodies against the SARS-CoV-2 spike protein. In addition, the immune response intensity was increased by repeated vaccine administration. In conclusion, both the approximate lethal dose and the no observed adverse effect level for rVSVInd(GML)-mspSGtc exceeded 4 × 109 PFU/mL in NZW rabbits. Overall, rVSVInd(GML)-mspSGtc induced no adverse effects at the maximum dosage tested; however, its efficacy warrants further clinical evaluation.

19.
Biochem Biophys Res Commun ; 419(4): 676-81, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22382031

RESUMO

GFP and its derivatives are commonly used as non-invasive in vivo reporters. These fluorescent proteins have been employed to analyze expression level, localization and movement of proteins, as well as protein interaction. However, they cannot be utilized under anaerobic conditions due to the oxygen requirement for the maturation of the fluorophore. Thus, other proteins with a different mechanism of fluorescence emission are needed. We reported here a blue fluorescent protein, named mBFP, that was derived from metagenomic DNA. This protein consisting of 248 amino acids was overexpressed (>35% of the total protein) in a soluble form in Escherichia coli. mBFP showed a distinct fluorescence pattern that was NADPH-dependent and could be used to image live cells under anaerobic conditions. Thus, mBFP holds great promise for use as a reporter in a broad range of applications.


Assuntos
Fungos/genética , Genes Reporter , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Metagenoma , Oxigênio/química , Folhas de Planta/microbiologia , Sequência de Aminoácidos , Clonagem Molecular , Escherichia coli/genética , Biblioteca Gênica , Vetores Genéticos/genética , Proteínas Luminescentes/isolamento & purificação , Dados de Sequência Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Seleção Genética , Solubilidade
20.
Psychol Rep ; 125(2): 1068-1085, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33530864

RESUMO

The purpose of this study was to test the moderating effects of adult attachment in the association between extroversion and subjective well-being in Korea. A total of 334 students recruited from four universities in Korea completed self-reported questionnaires regarding extroversion, attachment, and subjective well-being. The results showed that the innate extroverted orientation of university students affected positive emotions only when the level of attachment avoidance was low. In contrast, although university students had an extroverted orientation, their extroversion did not have a significant influence on positive emotions when their level of attachment avoidance was high. The findings of this study suggest that high levels of attachment avoidance may prevent for extroverts from experiencing positive emotions.


Assuntos
Extroversão Psicológica , Apego ao Objeto , Adulto , Ansiedade/psicologia , Humanos , República da Coreia , Estudantes/psicologia , Inquéritos e Questionários , Universidades
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