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1.
Plant J ; 118(5): 1312-1326, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38319894

RESUMO

Lignin is an important component of plant cell walls and plays crucial roles in the essential agronomic traits of tea quality and tenderness. However, the molecular mechanisms underlying the regulation of lignin biosynthesis in tea plants remain unclear. CsWRKY13 acts as a negative regulator of lignin biosynthesis in tea plants. In this study, we identified a GRAS transcription factor, phytochrome A signal transduction 1 (CsPAT1), that interacts with CsWRKY13. Silencing CsPAT1 expression in tea plants and heterologous overexpression in Arabidopsis demonstrated that CsPAT1 positively regulates lignin accumulation. Further investigation revealed that CsWRKY13 directly binds to the promoters of CsPAL and CsC4H and suppresses transcription of CsPAL and CsC4H. CsPAT1 indirectly affects the promoter activities of CsPAL and CsC4H by interacting with CsWRKY13, thereby facilitating lignin biosynthesis in tea plants. Compared with the expression of CsWRKY13 alone, the co-expression of CsPAT1 and CsWRKY13 in Oryza sativa significantly increased lignin biosynthesis. Conversely, compared with the expression of CsPAT1 alone, the co-expression of CsPAT1 and CsWRKY13 in O. sativa significantly reduced lignin accumulation. These results demonstrated the antagonistic regulation of the lignin biosynthesis pathway by CsPAT1 and CsWRKY13. These findings improve our understanding of lignin biosynthesis mechanisms in tea plants and provide insights into the role of the GRAS transcription factor family in lignin accumulation.


Assuntos
Camellia sinensis , Regulação da Expressão Gênica de Plantas , Lignina , Proteínas de Plantas , Fatores de Transcrição , Lignina/metabolismo , Lignina/biossíntese , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Camellia sinensis/genética , Camellia sinensis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética
2.
BMC Plant Biol ; 24(1): 333, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664694

RESUMO

BACKGROUND: The circadian clock, also known as the circadian rhythm, is responsible for predicting daily and seasonal changes in the environment, and adjusting various physiological and developmental processes to the appropriate times during plant growth and development. The circadian clock controls the expression of the Lhcb gene, which encodes the chlorophyll a/b binding protein. However, the roles of the Lhcb gene in tea plant remain unclear. RESULTS: In this study, a total of 16 CsLhcb genes were identified based on the tea plant genome, which were distributed on 8 chromosomes of the tea plant. The promoter regions of CsLhcb genes have a variety of cis-acting elements including hormonal, abiotic stress responses and light response elements. The CsLhcb family genes are involved in the light response process in tea plant. The photosynthetic parameter of tea leaves showed rhythmic changes during the two photoperiod periods (48 h). Stomata are basically open during the day and closed at night. Real-time quantitative PCR results showed that most of the CsLhcb family genes were highly expressed during the day, but were less expressed at night. CONCLUSIONS: Results indicated that CsLhcb genes were involved in the circadian clock process of tea plant, it also provided potential references for further understanding of the function of CsLhcb gene family in tea plant.


Assuntos
Camellia sinensis , Ritmo Circadiano , Fotossíntese , Fotossíntese/genética , Camellia sinensis/genética , Camellia sinensis/fisiologia , Ritmo Circadiano/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genes de Plantas , Família Multigênica , Proteínas de Ligação à Clorofila/genética , Proteínas de Ligação à Clorofila/metabolismo , Fotoperíodo
3.
Oral Dis ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735757

RESUMO

BACKGROUND: This study aimed to evaluate the incidence of implant failure in patients with oral lichen planus (OLP) and investigate the potential association between OLP and peri-implant diseases. MATERIALS AND METHODS: Embase, Web of Science, PubMed, and Scopus databases were searched for studies with no time restrictions. Meta-analysis was performed calculating pooled proportion of peri-implantitis (PI), peri-implant mucositis (PIM), and bleeding on probing (BOP) prevalence using fixed-effects model. Odds ratio and corresponding 95% CI were calculated to assess the potential risk of PI, PIM, and BOP in dental implant patients with OLP compared to healthy controls. RESULTS: Implant failure rate was 4.38% at the patient level and 4.37% at the implant level. Six patients (3.92%) from five studies were diagnosed with oral cancer after receiving implant. The prevalence of PI, PIM, and BOP at the implant level were 14.00%, 20.00%, and 40.00%, respectively. There was no significant difference in the occurrence of PI and PIM between OLP patients and healthy controls. CONCLUSIONS: Stabilized OLP is not considered a significant risk factor for peri-implant diseases. It is advised against placing implants or prostheses during the acute phase of the disease. Histopathological investigation to differentiate OLP from oral lichenoid dysplasia is crucial.

4.
BMC Oral Health ; 24(1): 51, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191371

RESUMO

OBJECTIVE: The aim of this study was to evaluate the outcome and risk factors for chairside CAD/CAM full cusp coverage restorations on endodontically treated posterior teeth after 3 years of follow-up. METHODS: A total of 245 endodontically treated posterior teeth of 224 patients were included and restored with CAD/CAM full cusp coverage all-ceramic restorations according to a standardized protocol. Patients were recalled after treatments 1 to 3 years and underwent clinical and radiological examinations. At recall, modified FDI criteria were used to determine treatment outcomes by 2 evaluators. Success was determined when FDI scores were 1-2, and failure was indicated when FDI scores were 5. Logistic regression analysis was performed to evaluate potential risk factors. RESULTS: A total of 183 patients presented at recall, and the clinical outcomes of 201 teeth were analyzed with a recall rate of 82.0% for teeth and 81.7% for patients after 1-3 years of follow-up.185 of 201 teeth were found to have FDI scores of 1-2, and the success rate was 92%. No teeth were extracted during the follow-up period. Fourteen failed cases with an FDI score of 5 presented restoration dislocation, fracture of restoration or/and tooth. Logistic regression analysis revealed that oral parafunction (OR 2.281, 95% CI 2.2 ~ 47.5, P value 0.01) was a risk factor for success rate. CONCLUSION: Chairside CAD/CAM all-ceramic full cusp coverage restoration was (could be) a promising alternative for restoring endodontically treated posterior teeth.


Assuntos
Cerâmica , Luxações Articulares , Humanos , Estudos Prospectivos , Desenho Assistido por Computador , Fatores de Risco
5.
PLoS Pathog ; 16(3): e1008417, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32187228

RESUMO

Streptococcus pneumoniae is well known for phase variation between opaque (O) and transparent (T) colonies within clonal populations. While the O variant is specialized in invasive infection (with a thicker capsule and higher resistance to host clearance), the T counterpart possesses a relatively thinner capsule and thereby higher airway adherence and colonization. Our previous study found that phase variation is caused by reversible switches of the "opaque ON-or-OFF" methylomes or methylation patterns of pneumococcal genome, which is dominantly driven by the PsrA-catalyzed inversions of the DNA methyltransferase hsdS genes. This study revealed that switch frequency between the O and T variants is regulated by five transcriptional response regulators (rr) of the two-component systems (TCSs). The mutants of rr06, rr08, rr09, rr11 and rr14 produced significantly fewer O and more T colonies. Further mutagenesis revealed that RR06, RR08, RR09 and RR11 enrich the O variant by modulating the directions of the PsrA-catalyzed inversion reactions. In contrast, the impact of RR14 (RitR) on phase variation is independent of PsrA. Consistently, SMRT sequencing uncovered significantly diminished "opaque ON" methylome in the mutants of rr06, rr08, rr09 and rr11 but not that of rr14. Lastly, the phosphorylated form of RR11 was shown to activate the transcription of comW and two sugar utilization systems that are necessary for maintenance of the "opaque ON" genotype and phenotype. This work has thus uncovered multiple novel mechanisms that balance pneumococcal epigenetic status and physiology.


Assuntos
Proteínas de Bactérias , Metilação de DNA , Enzimas de Restrição-Modificação do DNA , DNA Bacteriano , Epigênese Genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Streptococcus pneumoniae , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Enzimas de Restrição-Modificação do DNA/genética , Enzimas de Restrição-Modificação do DNA/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/metabolismo
6.
Acta Pharmacol Sin ; 43(1): 157-166, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33758355

RESUMO

Long noncoding RNAs (lncRNAs) are involved in a variety of cancers, but the role of LncRNA DUBR in lung adenocarcinoma (LUAD), the most prevalent form of lung cancer, remains unclear. In this study we investigated the expression of DUBR in LUAD to ascertain its association with the clinical pathology and prognosis of LUAD. Analysis of mRNA expression in The Cancer Genome Atlas (TCGA) LUAD database and in-house LUAD cohort (n = 94) showed that DUBR was significantly downregulated in LUAD, and was associated with poor prognosis. In LUAD cell lines (H1975, A549), overexpression of DUBR significantly suppressed the migration and invasion of the LUAD cells. We demonstrated that c-Myc could bind to the promoter of DUBR, and transcriptionally suppressed its expression. Knockdown of c-Myc almost completely blocked the invasion and migration of LUAD cells, whereas knockdown of DUBR partially rescued c-Myc-knockdown suppressed cell migration and invasion. Furthermore, DUBR overexpression significantly increased the expression of a downstream protein of DUBR, zinc finger, and BTB domain containing 11 (ZBTB11), in H1975 and A549 cells; knockdown of ZBTB11 partially rescued the DUBR-overexpression suppressed cell migration and invasion; knockdown of c-Myc significantly upregulated the expression of ZBTB11 in LUAD cells. Finally, we revealed that DUBR/ZBTB11 axis suppressed oxidative phosphorylation in LUAD cells. In short, we demonstrate that c-Myc/DUBR/ZBTB11 axis suppresses migration and invasion of LUAD by attenuating cell oxidative phosphorylation, which provides new insights into the regulatory mechanism of DUBR.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , RNA Longo não Codificante/metabolismo , Adenocarcinoma de Pulmão/diagnóstico , Domínio BTB-POZ , Movimento Celular , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Humanos , Neoplasias Pulmonares/diagnóstico , Estrutura Molecular , Fosforilação Oxidativa , RNA Longo não Codificante/genética , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
7.
J Craniofac Surg ; 33(7): 2216-2219, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35119412

RESUMO

PURPOSE: The present study aimed to investigate the clinical efficacy of simultaneous management of condylar osteochondroma and its secondary dentofacial deformities using an intraoral surgical approach. METHODS: Six patients with condylar osteochondroma were treated with intraoral vertical ramus osteotomies and condylar resection. The free rising branch was used for reconstructing the temporomandibular joint. The simultaneous orthognathic surgery and plastic surgery were performed sequentially to correct the secondary dentofacial deformities. The indexes of aesthetic symmetry, occlusion relationship, temporomandibular joint function, condylar height, and volume change were assessed in the subsequential follow up. RESULTS: The mean follow up period was 31 months. All patients had no tumor recurrence. The ipsilateral joint function, occlusal relationship, and facial symmetry were satisfied. The ipsilateral condylar reconstruction had no obvious bone resorption and the ramus height was maintained well. Postoperative assessment showed the preoperative design was accurately fulfilled. CONCLUSIONS: The simultaneous condylar osteochondroma resection and temporomandibular joint reconstruction using intraoral approach avoids extraoral scars and correct facial asymmetry without compromising the long-term joint function and occlusal relationship.


Assuntos
Deformidades Dentofaciais , Neoplasias Mandibulares , Procedimentos Cirúrgicos Ortognáticos , Osteocondroma , Deformidades Dentofaciais/cirurgia , Estética Dentária , Humanos , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/patologia , Côndilo Mandibular/cirurgia , Neoplasias Mandibulares/complicações , Neoplasias Mandibulares/diagnóstico por imagem , Neoplasias Mandibulares/cirurgia , Recidiva Local de Neoplasia/patologia , Osteocondroma/complicações , Osteocondroma/diagnóstico por imagem , Osteocondroma/cirurgia
8.
Int J Mol Sci ; 23(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36012559

RESUMO

Nitrate nitrogen is an important nitrogen source for tea plants' growth and development. LBD transcription factors play important roles in response to the presence of nitrate in plants. The functional study of LBD transcription factors in tea plants remains limited. In this study, the LBD family gene CsLBD39 was isolated and characterized from tea plants. Sequence analysis indicated that CsLBD39 contained a highly conserved CX2CX6CX3CX domain. The phylogenetic tree assay showed that CsLBD39 belonged to class II subfamily of the LBD family. CsLBD39 was highly expressed in flowers and root; we determined that its expression could be induced by nitrate treatment. The CsLBD39 protein was located in the nucleus and has transcriptional activation activity in yeast. Compared with the wild type, overexpression of CsLBD39 gene in Arabidopsis resulted in smaller rosettes, shorter main roots, reduced lateral roots and lower plant weights. The nitrate content and the expression levels of genes related to nitrate transport and regulation were decreased in transgenic Arabidopsis hosting CsLBD39 gene. Compared with the wild type, CsLBD39 overexpression in transgenic Arabidopsis had smaller cell structure of leaves, shorter diameter of stem cross section, and slender and compact cell of stem longitudinal section. Under KNO3 treatment, the contents of nitrate, anthocyanins, and chlorophyll in leaves, and the content of nitrate in roots of Arabidopsis overexpressing CsLBD39 were reduced, the expression levels of nitrate transport and regulation related genes were decreased. The results revealed that CsLBD39 may be involved in nitrate signal transduction in tea plants as a negative regulator and laid the groundwork for future studies into the mechanism of nitrate response.


Assuntos
Arabidopsis , Camellia sinensis , Antocianinas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Camellia sinensis/metabolismo , Regulação da Expressão Gênica de Plantas , Nitratos/metabolismo , Nitrogênio/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Chá/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
J Bacteriol ; 201(6)2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30617241

RESUMO

Streptococcus pneumoniae (pneumococcus), a major human pathogen, is well known for its adaptation to various host environments. Multiple DNA inversions in the three DNA methyltransferase hsdS genes (hsdSA, hsdSB, and hsdSC) of the colony opacity determinant (cod) locus generate extensive epigenetic and phenotypic diversity. However, it is unclear whether all three hsdS genes are functional and how the inversions mechanistically occur. In this work, our transcriptional analysis revealed active expression of hsdSA but not hsdSB and hsdSC, indicating that hsdSB and hsdSC do not produce functional proteins and instead act as sources for altering the sequence of hsdSA by DNA inversions. Consistent with our previous finding that the hsdS inversions are mediated by three pairs of inverted repeats (IR1, IR2, and IR3), this study showed that the 15-bp IR1 and its upstream sequence are strictly required for the inversion between hsdSA and hsdSB Furthermore, a single tyrosine recombinase PsrA catalyzes the inversions mediated by IR1, IR2, and IR3, based on the dramatic loss of these inversions in the psrA mutant. Surprisingly, PsrA-independent inversions were also detected in the hsdS sequences flanked by the IR2 (298 bp) and IR3 (85 bp) long inverted repeats, which appear to occur spontaneously in the absence of site-specific or RecA-mediated recombination. Because the HsdS subunit is responsible for the sequence specificity of type I restriction modification DNA methyltransferase, these results have revealed that S. pneumoniae varies the methylation patterns of the genome DNA (epigenetic status) by employing multiple mechanisms of DNA inversion in the cod locus.IMPORTANCEStreptococcus pneumoniae is a major pathogen of human infections with the capacity for adaptation to host environments, but the molecular mechanisms behind this phenomenon remain unclear. Previous studies reveal that pneumococcus extends epigenetic and phenotypic diversity by DNA inversions in three methyltransferase hsdS genes of the cod locus. This work revealed that only the hsdS gene that is in the same orientation as hsdM is actively transcribed, but the other two are silent, serving as DNA sources for inversions. While most of the hsdS inversions are catalyzed by PsrA recombinase, the sequences bound by long inverted repeats also undergo inversions via an unknown mechanism. Our results revealed that S. pneumoniae switches the methylation patterns of the genome (epigenetics) by employing multiple mechanisms of DNA inversion.


Assuntos
Proteínas de Bactérias/genética , Inversão Cromossômica , Enzimas de Restrição-Modificação do DNA/genética , Loci Gênicos , Streptococcus pneumoniae/genética , Proteínas de Bactérias/biossíntese , Enzimas de Restrição-Modificação do DNA/biossíntese , Perfilação da Expressão Gênica , Variação Genética , Sequências Repetidas Invertidas , Recombinação Genética
10.
Opt Express ; 27(23): 33243-33250, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31878397

RESUMO

This paper proposes a mid-infrared chiral structure, which consists of L-shaped indium tin oxide (ITO) films formed on self-assembled monolayer polystyrene microspheres in two orthogonal directions by oblique angle deposition technique. Experimental results demonstrate that the structure exhibit circular dichroism (CD) responses in the range of 2.5 - 4 µm. As the thickness difference of the ITO films in the two orthogonal directions increases, the CD response enhances. The reason is that the ITO films produce cross dipoles and their bigger differences in thickness bring to bigger phase differences in optical chirality. The experimental results also demonstrate that the CD signals are evidently stronger than those of the structure consisting of silver in the mid-infrared band. This work provides a new idea for the fabrication of mid-infrared chiral structures, which have potential applications in the polarization state control of mid-infrared lasers.

11.
Planta ; 247(6): 1363-1375, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29520459

RESUMO

MAIN CONCLUSION: This study showed that a galactosyltransferase, AgUCGalT1, is involved in anthocyanin galactosylation in purple celery. Celery is a well-known vegetable because of its rich nutrients, low calories, and medicinal values. Its petioles and leaf blades are the main organs acting as nutrient sources. UDP-galactose: cyanidin 3-O-galactosyltransferase can transfer the galactosyl moiety from UDP-galactose to the 3-O-position of cyanidin through glycosylation. This process enhances the stability and water solubility of anthocyanins. In the present study, LC-MS data indicated that abundant cyanidin-based anthocyanins accumulated in the petioles of purple celery ('Nanxuan liuhe purple celery'). A gene encoding UDP-galactose: cyanidin 3-O-galactosyltransferase, namely AgUCGalT1, was isolated from purple celery and expressed in Escherichia coli BL21 (DE3). Sequence alignments revealed that the AgUCGalT1 protein contained a highly conserved putative secondary plant glycosyltransferase (PSPG) motif. The glycosylation product catalyzed by AgUCGalT1 was detected using UPLC equipment. The recombinant AgUCGalT1 had an optimal enzyme activity at 35 °C and pH 8.0, and showed highest enzyme activity toward cyanidin among the enzyme activities involving other substances, namely, peonidin, quercetin, and kaempferol. The expression levels of AgUCGalT1 were positively correlated with the total anthocyanin contents in purple and non-purple celery varieties. Crude enzymes extracted from purple celery exhibited glycosylation ability, whereas crude enzymes obtained from non-purple celery did not have this ability. This work provided evidence as a basis for investigations on the function of AgUCGalT1 in anthocyanin glycosylation in purple celery.


Assuntos
Antocianinas/metabolismo , Apium/enzimologia , Galactosiltransferases/metabolismo , Motivos de Aminoácidos , Antocianinas/química , Apium/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Galactosiltransferases/genética , Galactosiltransferases/isolamento & purificação , Glicosilação , Modelos Estruturais , Filogenia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
12.
PLoS Pathog ; 12(7): e1005762, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27427949

RESUMO

DNA methylation is an important epigenetic mechanism for phenotypic diversification in all forms of life. We previously described remarkable cell-to-cell heterogeneity in epigenetic pattern within a clonal population of Streptococcus pneumoniae, a leading human pathogen. We here report that the epigenetic diversity is caused by extensive DNA inversions among hsdSA, hsdSB, and hsdSC, three methyltransferase hsdS genes in the Spn556II type-I restriction modification (R-M) locus. Because hsdSA encodes the sequence recognition subunit of this type-I R-M DNA methyltransferase, these site-specific recombinations generate pneumococcal cells with variable HsdSA alleles and thereby diverse genome methylation patterns. Most importantly, the DNA methylation pattern specified by the HsdSA1 allele leads to the formation of opaque colonies, whereas the pneumococci lacking HsdSA1 produce transparent colonies. Furthermore, this HsdSA1-dependent phase variation requires intact DNA methylase activity encoded by hsdM in the Spn556II (renamed colony opacity determinant or cod) locus. Thus, the DNA inversion-driven ON/OFF switch of the hsdSA1 allele in the cod locus and resulting epigenetic switch dictate the phase variation between the opaque and transparent phenotypes. Phase variation has been well documented for its importance in pneumococcal carriage and invasive infection, but its molecular basis remains unclear. Our work has discovered a novel epigenetic cause for this significant pathobiology phenomenon in S. pneumoniae. Lastly, our findings broadly represents a significant advancement in our understanding of bacterial R-M systems and their potential in shaping epigenetic and phenotypic diversity of the prokaryotic organisms because similar site-specific recombination systems widely exist in many archaeal and bacterial species.


Assuntos
Proteínas de Bactérias/genética , Metilação de DNA/genética , Enzimas de Restrição-Modificação do DNA/genética , Epigênese Genética/genética , Streptococcus pneumoniae/genética , Animais , DNA Bacteriano/genética , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Mutagênese Sítio-Dirigida , Fenótipo , Infecções Pneumocócicas/microbiologia , Reação em Cadeia da Polimerase
13.
J Bacteriol ; 199(14)2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28484041

RESUMO

Reversible or phenotypic tolerance to antibiotics within microbial populations has been implicated in treatment failure of chronic infections and development of persister cells. However, the molecular mechanisms regulating phenotypic drug tolerance are largely unknown. In this study, we identified a four-gene operon in Streptococcus pneumoniae that contributes to phenotypic tolerance to vancomycin (ptv). RNA sequencing, quantiative reverse transcriptase PCR, and transcriptional luciferase reporter experiments revealed that transcription of the ptv operon (consisting of ptvR, ptvA, ptvB, and ptvC) is induced by exposure to vancomycin. Further investigation showed that transcription of the ptv operon is repressed by PtvR, a PadR family repressor. Transcriptional induction of the ptv operon by vancomycin was achieved by transcriptional derepression of this locus, which was mediated by PtvR. Importantly, fully derepressing ptvABC by deleting ptvR or overexpressing the ptv operon with an exogenous promoter significantly enhanced vancomycin tolerance. Gene deletion analysis revealed that PtvA, PtvB, and PtvC are all required for the PtvR-regulated phenotypic tolerance to vancomycin. Finally, the results of an electrophoretic mobility shift assay with recombinant PtvR showed that PtvR represses the transcription of the ptv operon by binding to two palindromic sequences within the ptv promoter. Together, the ptv locus represents an inducible system in S. pneumoniae in response to stressful conditions, including those caused by antibiotics.IMPORTANCE Reversible or phenotypic tolerance to antibiotics within microbial populations is associated with treatment failure of bacterial diseases, but the underlying mechanisms regulating phenotypic drug tolerance remain obscure. This study reports our finding of a multigene locus that contributes to inducible tolerance to vancomycin in Streptococcus pneumoniae, an important opportunistic human pathogen. The vancomycin tolerance phenotype depends on the PtvR transcriptional repressor and three predicted membrane-associated proteins encoded by the ptv locus. This represents the first example of a gene locus in S. pneumoniae that is responsible for antibiotic tolerance and has important implications for further understanding bacterial responses and phenotypic tolerance to antibiotic treatment in this and other pathogens.


Assuntos
Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana/genética , Streptococcus pneumoniae/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Vancomicina/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/metabolismo , Fatores de Transcrição/genética
14.
Mol Cancer ; 16(1): 9, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086904

RESUMO

BACKGROUND: With more than 600,000 mortalities each year, colorectal cancer (CRC) is the third most commonly diagnosed type of cancer worldwide. Recently, mechanisms involving noncoding RNAs have been implicated in the development of CRC. METHODS: We examined expression levels of lncRNA CRNDE and miR-181a-5p in 64 cases of CRC tissues and cell lines by qRT-PCR. Gain-of-function and loss-of-function assays were performed to examine the effect of CRNDE and miR-181a-5p on proliferation and chemoresistance of CRC cells. Using fluorescence reporter and western blot assays, we also explored the possible mechanisms of CRNDE in CRC cells. RESULTS: In this study, we found that the expression levels of the CRNDE were upregulated in CRC clinical tissue samples. We identified microRNA miR-181a-5p as an inhibitory target of CRNDE. Both CRNDE knockdown and miR-181a-5p overexpression in CRC cell lines led to inhibited cell proliferation and reduced chemoresistance. We also determined that ß-catenin and TCF4 were inhibitory targets of miR-181a-5p, and that Wnt/ß-catenin signaling was inhibited by both CRNDE knockdown and miR-181a-5p overexpression. Significantly, we found that the repression of cell proliferation, the reduction of chemoresistance, and the inhibition of Wnt/ß-catenin signaling induced by CRNDE knockdown would require the increased expression of miR-181a-5p. CONCLUSIONS: Our study demonstrated that the lncRNA CRNDE could regulate the progression and chemoresistance of CRC via modulating the expression levels of miR-181a-5p and the activity of Wnt/ß-catenin signaling.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Longo não Codificante/genética , Via de Sinalização Wnt , Adulto , Idoso , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Interferência de RNA , Fator de Transcrição 4 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Carga Tumoral , beta Catenina/genética , beta Catenina/metabolismo
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 18(11): 1136-1140, 2016 Nov.
Artigo em Zh | MEDLINE | ID: mdl-27817780

RESUMO

X-linked ichthyosis (XLI) is a metabolic disease with steroid sulfatase deficiency and often occurs at birth or shortly after birth. The encoding gene of steroid sulfatase, STS, is located on the short arm of the X chromosome, and STS deletion or mutation can lead to the development of this disease. This study collected the data on the clinical phenotype from a family, and the proband, a boy aged 11 years with full-term vaginal delivery, had dry and rough skin and black-brown scaly patches, mainly in the abdomen and extensor aspect of extremities. Peripheral blood samples were collected from each family member and DNA was extracted. Multiplex ligation-dependent probe amplification (MLPA) was used to measure the copy number of STS on the X chromosome. Whole-genome microarray was used to determine the size of the segment with microdeletion in the X chromosome. MLPA was then used for prenatal diagnosis for the mother of the proband. The results revealed that the proband and another two male patients had hemizygotes in STS deletion. Gene microarray identified a rare deletion with a size of 1.6 Mb at Xp22.31 (chrX: 6,516,735-8,131,442). Two female family members were found to be carriers. Prenatal diagnosis showed that the fetus carried by the proband's mother was a carrier of this microdeletion. This study showed STS gene deletion in this family of XLI, which causes the unique skin lesions of XLI. MLPA is a convenient and reliable technique for the molecular and prenatal diagnosis of XLI.


Assuntos
Ictiose Ligada ao Cromossomo X/genética , Mutação , Diagnóstico Pré-Natal , Criança , Humanos , Ictiose Ligada ao Cromossomo X/diagnóstico , Masculino , Polimorfismo de Nucleotídeo Único , Esteril-Sulfatase/genética
17.
Shanghai Kou Qiang Yi Xue ; 33(1): 80-84, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38583030

RESUMO

PURPOSE: To investigate the effect of endoscopy-aided non-incisional periodontal regeneration technique (NIT) in the treatment of alveolar bone angular resorption. METHODS: Thirteen patients with severe periodontitis(13 diseased teeth) were selected. All patients had alveolar bone angular resorption on adjacent surface. The patients received NIT treatment 6 weeks after periodontal primary therapy. The visualization of subgingival environment was acquired by the periodontal endoscopy. Following the removal of the subgingival plaque, calculus and intra-bony granulation tissue, bone grafting materials were placed into the intra-bony defects with the assistance of a delicate gingival protector. No flap was elevated and no sutures were applied. Probing depth (PD), gingival recession (GR), clinical attachment level (CAL), as well as radiographic parameters were evaluated at baseline and 2 years after treatment. SPSS 22.0 software package was used for data analysis. RESULTS: At 2-years follow-up, an average CAL gain of (3.65±2.10) mm (P<0.001), PD reduction of (4.42±1.66) mm (P<0.001), and minimal increase in GR of (0.38±0.87) mm (P=0.25) were observed. Alveolar bone was significantly improved at 2-years follow-up on radiographs (P<0.001). CONCLUSIONS: For angular resorption site of alveolar bone, NIT treatment can obtain good periodontal regeneration results without flap inversion.


Assuntos
Perda do Osso Alveolar , Retração Gengival , Periodontite , Humanos , Seguimentos , Bolsa Periodontal/cirurgia , Periodontite/diagnóstico por imagem , Periodontite/cirurgia , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/cirurgia , Processo Alveolar/cirurgia , Retração Gengival/cirurgia , Endoscopia , Regeneração Tecidual Guiada Periodontal/métodos , Perda da Inserção Periodontal/cirurgia , Resultado do Tratamento , Regeneração Óssea
18.
Orphanet J Rare Dis ; 19(1): 179, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685110

RESUMO

Mucopolysaccharidoses (MPSs) are caused by a deficiency in the enzymes needed to degrade glycosaminoglycans (GAGs) in the lysosome. The storage of GAGs leads to the involvement of several systems and even to the death of the patient. In recent years, an increasing number of therapies have increased the treatment options available to patients. Early treatment is beneficial in improving the prognosis, but children with MPSs are often delayed in their diagnosis. Therefore, there is an urgent need to develop a method for early screening and diagnosis of the disease. Tandem mass spectrometry (MS/MS) is an analytical method that can detect multiple substrates or enzymes simultaneously. GAGs are reliable markers of MPSs. MS/MS can be used to screen children at an early stage of the disease, to improve prognosis by treating them before symptoms appear, to evaluate the effectiveness of treatment, and for metabolomic analysis or to find suitable biomarkers. In the future, MS/MS could be used to further identify suitable biomarkers for MPSs for early diagnosis and to detect efficacy.


Assuntos
Mucopolissacaridoses , Espectrometria de Massas em Tandem , Humanos , Mucopolissacaridoses/diagnóstico , Mucopolissacaridoses/metabolismo , Espectrometria de Massas em Tandem/métodos , Biomarcadores/metabolismo , Glicosaminoglicanos/metabolismo
19.
Cancers (Basel) ; 15(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37174004

RESUMO

OBJECTIVES: This systematic review and meta-analysis aims to evaluate the evidence on the malignant potential of oral lichenoid conditions (OLCs) including oral lichen planus (OLP), oral lichenoid lesions (OLL), and lichenoid mucositis dysplasia (LMD). In addition, it aims to compare the rate of malignant transformation (MT) in OLP patients diagnosed according to different diagnostic criteria, and to investigate the possible risk factors for OLP MT into OSCC. MATERIALS AND METHODS: A standardized search strategy was applied across four databases (PubMed, Embase, Web of Science, and Scopus). Screening, identification and reporting followed the PRISMA framework. Data on MT were calculated as a pooled proportion (PP), subgroup analyses and possible risk factors for MT were pooled as odds ratios (ORs). RESULTS: Among 54 studies with 24,277 patients, the PP for OLCs MT was 1.07% (95% CI [0.82, 1.32]). The estimated MT rate for OLP, OLL and LMD was 0.94%, 1.95% and 6.31%, respectively. The PP OLP MT rate using the 2003 modified WHO criteria group was lower than that using the non-2003 criteria (0.86%; 95% CI [0.51, 1.22] versus 1.01%; 95% CI [0.67, 1.35]). A higher odds ratio of MT was observed for red OLP lesions (OR = 3.52; 95% CI [2.20, 5.64]), smokers (OR = 1.79; 95% CI [1.02, 3.03]), alcohol consumers (OR = 3.27, 95% CI [1.11, 9.64]) and those infected with HCV (OR = 2.55, 95% CI [1.58, 4.13]), compared to those without these risk factors. CONCLUSIONS: OLP and OLL carry a low risk of developing OSCC. MT rates differed based on diagnostic criteria. A higher odds ratio of MT was observed among red OLP lesions, smokers, alcohol consumers, and HCV-positive patients. These findings have implications for practice and policies.

20.
Front Oral Health ; 4: 1322458, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38169876

RESUMO

Introduction: The aim of this systematic review is to provide a clinical update of the current knowledge on COVID-19 and oral mucosal lesions, to analyze the types and prevalence of oral mucosal lesions in patients with COVID-19, and to clarify the potential association between COVID-19 and oral mucosal lesions. Methods: The literature search was conducted using PubMed, Web of Science, Scopus and the Cochrane Library, as well as literatures via manual searches of the reference lists of included studies. Studies published in English that mentioned oral mucosal lesions in patients with COVID-19 were included, resulting in a total of 31 studies. Results: Most of the included studies were considered to have a moderate to high risk of bias according to the Joanna Briggs Institute bias assessment tools. Based on COVID-19 severity, the characteristics and patterns of oral mucosal lesions in COVID-19 patients were described, analyzed and synthesized. Overall, ulcers without specific diagnosis had the highest prevalence in COVID-19 patients, followed by traumatic ulcers, candidiasis, petechiae and aphthous-like lesions. Homogeneity of data cannot be achieved in statical analysis, indicating randomness of outcome (ulcers without specific diagnosis, 95% CI: 28%-96%, I2 = 98.7%). Discussion: Given the limited evidence from currently available studies, the association between COVID-19 and oral mucosal lesions remains difficult to clarify. Healthcare professionals should be aware of the possible association between COVID-19 and oral mucosal lesions, and we hereby discuss our findings.

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