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1.
Proc Natl Acad Sci U S A ; 120(24): e2108118120, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37276386

RESUMO

Nucleic acids can undergo conformational changes upon binding small molecules. These conformational changes can be exploited to develop new therapeutic strategies through control of gene expression or triggering of cellular responses and can also be used to develop sensors for small molecules such as neurotransmitters. Many analytical approaches can detect dynamic conformational change of nucleic acids, but they need labeling, are expensive, and have limited time resolution. The nanopore approach can provide a conformational snapshot for each nucleic acid molecule detected, but has not been reported to detect dynamic nucleic acid conformational change in response to small -molecule binding. Here we demonstrate a modular, label-free, nucleic acid-docked nanopore capable of revealing time-resolved, small molecule-induced, single nucleic acid molecule conformational transitions with millisecond resolution. By using the dopamine-, serotonin-, and theophylline-binding aptamers as testbeds, we found that these nucleic acids scaffolds can be noncovalently docked inside the MspA protein pore by a cluster of site-specific charged residues. This docking mechanism enables the ion current through the pore to characteristically vary as the aptamer undergoes conformational changes, resulting in a sequence of current fluctuations that report binding and release of single ligand molecules from the aptamer. This nanopore tool can quantify specific ligands such as neurotransmitters, elucidate nucleic acid-ligand interactions, and pinpoint the nucleic acid motifs for ligand binding, showing the potential for small molecule biosensing, drug discovery assayed via RNA and DNA conformational changes, and the design of artificial riboswitch effectors in synthetic biology.


Assuntos
Aptâmeros de Nucleotídeos , Nanoporos , Riboswitch , Ligantes , Conformação de Ácido Nucleico , RNA , Aptâmeros de Nucleotídeos/química
2.
Cell Biol Int ; 48(6): 821-834, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38436129

RESUMO

Keratinocytes, located in the outermost layer of human skin, are pivotal cells to resist environmental damage. Cellular autophagy plays a critical role in eliminating damaged organelles and maintaining skin cell homeostasis. Low-dose 5-Aminolevulinic acid photodynamic therapy (ALA-PDT) has been demonstrated to enhance skin's antistress ability; however, the regulatory mechanisms of autophagy in keratinocytes remain unclear. In this study, we treated immortalized human keratinocytes (HaCaT cells) with low-dose ALA-PDT (0.5 mmol/L, 3 J/cm2). Through RNA-sequencing analysis, we identified that low-dose ALA-PDT modulated autophagy-related pathways in keratinocytes and pinpointed Unc-51-like kinase 1 (ULK1) as a key gene involved. Western blot results revealed that low-dose ALA-PDT treatment upregulated the expression of autophagy-related proteins Beclin-1 and LC3-II/LC3-I ratio. Notably, low-dose ALA-PDT regulated autophagy by inducing an appropriate level of reactive oxygen species (ROS), transiently reducing mitochondrial membrane potential, and decreasing adenosine triphosphate production; all these processes functioned on the AMP-activated protein kinase (AMPK)/ULK1 pathway to activate autophagy. Finally, we simulated external environmental damage using ultraviolet B (UVB) at a dose of 60 mJ/cm2 and observed that low-dose ALA-PDT mitigated UVB-induced cell apoptosis; however, this protective effect was reversed when using the autophagy inhibitor 3-methyladenine. Overall, these findings highlight how low-dose ALA-PDT enhances antistress ability in HaCaT cells through controlling ROS generation and activating the AMPK/ULK1 pathway to arouse cellular autophagy.


Assuntos
Proteínas Quinases Ativadas por AMP , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Autofagia , Queratinócitos , Transdução de Sinais , Humanos , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Autofagia/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Aminolevulínico/farmacologia , Células HaCaT , Potencial da Membrana Mitocondrial/efeitos dos fármacos
3.
Photodermatol Photoimmunol Photomed ; 39(3): 246-255, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36052757

RESUMO

BACKGROUND: Few studies have reported postoperative relapse of condyloma acuminatum (CA) after 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in human immunodeficiency virus (HIV) positive patients. METHODS: The clinical data of HIV-positive CA patients treated with ALA-PDT from October 2018 to December 2019 were analyzed retrospectively. Univariate and multivariate Cox regression was used to analyze the variables related to postoperative recurrence. Pearson correlation test was employed to analyze the correlation between CD4+ T cell count and postoperative recurrence rate. Kaplan-Meier method was used to compare the CA recurrence after ALA-PDT in low CD4 group and high CD4 group. RESULTS: A total of 38 HIV-positive patients with CA were included in the study. Among them, 26 patients experienced CA recurrence within 6 months, and the recurrence rate was 68.4%. CD4+ T cell count was 187.0 (79.0-596.0) cells/µl in relapsed patients and 406.0 (89.0-612.0) cells/µl in non-relapsed patients, showing a statistically significant difference (p = .005). Pearson correlation coefficient analysis revealed a negative correlation between CD4+ T cell count and postoperative recurrence rate (p = .005, r = -.443). Univariate regression analysis showed that CD4+ T cell count was correlated with postoperative recurrence, hazard ratio (HR) was 0.99 [95% Confidence interval (CI) = 0.99-1.0, p = .012]. Multivariate Cox regression analysis showed that with the low CD4+ T cell count as the reference, the high CD4+ T cell count was negatively correlated with postoperative recurrence (HR = 0.09, 95% CI 0.01-0.87, p = .038). CONCLUSIONS: Peripheral blood CD4+ T cell count can predict the CA recurrence rate after ALA-PDT in HIV-positive patients.


Assuntos
Condiloma Acuminado , Soropositividade para HIV , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Fotoquimioterapia/métodos , Ácido Aminolevulínico/uso terapêutico , Condiloma Acuminado/tratamento farmacológico , Condiloma Acuminado/etiologia , Linfócitos T CD4-Positivos , Contagem de Células
4.
J Gastroenterol Hepatol ; 37(7): 1275-1283, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35342997

RESUMO

BACKGROUND AND AIM: Duodenal ulcers, especially caused by increasingly drug-resistant Helicobacter pylori, are a concern in Asia. We compared oral vonoprazan versus lansoprazole for efficacy (healing duodenal ulcers) and safety in non-Japanese Asian patients. METHODS: In this phase 3, randomized (1:1), double-blind, double-dummy, parallel-group, non-inferiority study (April 5, 2017, to July 19, 2019), patients with ≥ 1 endoscopically confirmed duodenal ulcer, at 52 hospitals (China, South Korea, and Taiwan), received vonoprazan 20 mg once daily (QD) or lansoprazole 30 mg QD for 6 weeks maximum. Patients with H. pylori received bismuth-containing quadruple therapy including vonoprazan 20 mg twice daily (BID) or lansoprazole 30 mg BID, for 2 weeks, followed by vonoprazan or lansoprazole monotherapy QD (4 weeks maximum). Endpoints were endoscopically confirmed duodenal ulcer healing (Week 4/6; primary) and H. pylori eradication (4 weeks post-treatment; secondary); non-inferiority margins were -6% and -10%, using a two-sided 95% confidence interval (CI). RESULTS: Of 533 enrolled patients, one was lost to follow-up and one withdrew (full analysis set: 531 patients [vonoprazan, n = 263; lansoprazole, n = 268]; 85.4% = H. pylori positive). Vonoprazan was non-inferior to lansoprazole for duodenal ulcer healing (96.9% vs 96.5%; difference 0.4% [95% CI -3.00, 3.79]). H. pylori eradication rates were 91.5% (vonoprazan) and 86.8% (lansoprazole; difference 4.7% [95% CI -1.28, 10.69]). Vonoprazan and lansoprazole were well tolerated, with similar safety profiles, no new safety signals; no deaths occurred. CONCLUSIONS: Vonoprazan was well tolerated and non-inferior to lansoprazole for duodenal ulcer healing and achieved H. pylori eradication above the clinically meaningful threshold (90%), in non-Japanese Asian patients.


Assuntos
Antiulcerosos , Úlcera Duodenal , Infecções por Helicobacter , Helicobacter pylori , Amoxicilina , Antiulcerosos/efeitos adversos , Claritromicina , Método Duplo-Cego , Quimioterapia Combinada , Úlcera Duodenal/induzido quimicamente , Úlcera Duodenal/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Humanos , Lansoprazol/efeitos adversos , Recidiva Local de Neoplasia , Pirróis , Sulfonamidas
5.
BMC Cancer ; 21(1): 836, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34284746

RESUMO

BACKGROUND: Immunotherapy is a crucial therapeutic approach in oncology. However, most patients with head and neck squamous cell carcinoma (HNSCC) do not derive benefit from immunotherapy. Vascular endothelial growth factor (VEGF)/VEGF Receptor 2 (VEGFR2) signaling pathway is one of the most important pathways regulating angiogenesis in tumor. The combination of immunotherapy and anti-angiogenic therapy is considered to improve efficacy of immunotherapy. The correlation between VEGF signaling pathway and tumor immune microenvironment in HNSCC patients is unclear. METHODS: We utilized RNA sequencing and clinical data of HNSCC patients from the TCGA database to study the correlation between VEGF signaling pathway and tumor immune microenvironment, on aspect of immune cell infiltration, immune-related gene expression profiling and immune-related biological pathways. RESULTS: We observed that VEGF signaling pathway is positively correlated with immune cell infiltration, immune-related gene expression profiles, and the prognosis of HNSCC patients. The functional enrichment analysis of differentially expressed genes between different VEGF score subtypes detected multiple immune-related biological processes. CONCLUSION: Our findings suggested that combining anti-VEGF signaling pathway agents with immunotherapy, such as immune checkpoint inhibitors (ICI) therapy, may exhibit encouraging benefits in HNSCC.


Assuntos
Imunoterapia/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Feminino , Humanos , Masculino , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Microambiente Tumoral
6.
J Oral Pathol Med ; 49(2): 156-163, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31610043

RESUMO

BACKGROUND: Oral submucous fibrosis (OSF) is a chronic progressive oral disease with cancerous tendency. Arecoline plays an important role in the pathogenesis of OSF. Fibroblasts (FBs) are the primary cells involved in the pathogenesis of OSF. There is a change in CD4+ IL-17+ helper T cells (Th17) and CD4+ CD25+ Foxp3+ regulatory T cells (Treg) in OSF patients, but the molecular mechanisms of are not clearly understood. In this work, we studied the molecular mechanisms. METHODS: Enzyme digestion was used to extract primary FBs, and immunofluorescence was used to identify FBs. Cytotoxic experiment was then performed to determine the effect of arecoline on FB activity. Enzyme-linked immunosorbent assay (ELISA) was used to detect changes in the amount of cytokines. In addition, we treated human peripheral blood mononuclear cells (PBMC) with the above cytokines and detected their changes. Flow cytometry was used to detect the changes of Th17 and Treg, and quantitative-polymerase chain reaction (Q-PCR) was used to detect the changes of RORγt and Foxp3. RESULTS: We have found that the stimulation of arecoline on FBs increased interleukin-2, interleukin-6, and interleukin-21 (IL-2, IL-6, and IL-21) while decreased transforming growth cytokine-ß (TGF-ß). After the cytokine-containing supernatant was co-cultured with PBMC, the cytometry results showed that Th17 was increased, while Treg was significantly decreased and Q-PCR results showed that RORγt expression was increased and Foxp3 expression was decreased. CONCLUSION: The arecoline can affect inflammatory cytokines produced by FBs, which then act on immune cells Th17 and Treg, and make them change.


Assuntos
Linfócitos T Reguladores , Células Th17 , Arecolina , Citocinas , Fibroblastos , Fatores de Transcrição Forkhead , Humanos , Leucócitos Mononucleares
7.
Pharm Biol ; 58(1): 1244-1251, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33332205

RESUMO

CONTEXT: Oral submucous fibrosis (OSF) is a chronic and progressive disease. Arecoline, present in betel nuts, has been proposed as a vital aetiological factor. However, the underlying mechanism remains unclear. OBJECTIVES: This research elucidates the expression of tropomyosin-1 (TPM1) and its regulation mechanism in HaCaT cells treated with arecoline. MATERIALS AND METHODS: HaCaT cells were assigned into three groups: (1) Control; (2) Treated with arecoline (0.16 mM) for 48 h (3) Treated with arecoline (0.16 mM) and transfected with small interfering RNA (siRNA) for TPM1 (50 nM) for 48 h. CCK8, cell cycle, and apoptosis phenotypic analyses were performed. PCR and western blot analyses were performed to detect the expression level of TPM1 and examine the related signalling pathway. RESULTS: The IC50 of arecoline was approximately 50 µg/mL (0.21 mM). The arecoline dose (0.16 mM) and time (48 h) markedly increased TPM1 expression at the mRNA and protein levels in HaCaT cells. Arecoline suppressed the cell growth, caused cell cycle arrest at the G1 phase, and induced cell apoptosis in HaCaT cells. siRNA-mediated knockdown of TPM1 attenuated the effect of arecoline on cell proliferation, apoptosis, and cell cycle arrest at the G1 phase. Furthermore, blocking of the transforming growth factor (TGF)-ß receptor using SB431542 significantly suppressed TPM1 expression in the cells treated with arecoline. DISCUSSION AND CONCLUSIONS: Arecoline suppresses HaCaT cell viability by upregulating TPM1 through the TGF-ß/Smad signalling pathway. This research provides a scientific basis for further study of arecoline and TPM1 in OSF and can be generalised to broader pharmacological studies. TPM1 may be a promising molecular target for treating OSF.


Assuntos
Arecolina/toxicidade , Fibrose Oral Submucosa/induzido quimicamente , Proteínas Smad/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Tropomiosina/genética , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Células HaCaT , Humanos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tropomiosina/fisiologia , Regulação para Cima
8.
Diabetes Obes Metab ; 21(2): 234-243, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30129089

RESUMO

AIM: To compare the efficacy and safety of once-weekly dulaglutide with that of insulin glargine in combination with metformin and/or a sulphonylurea in mainly Asian patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: In this 52-week, randomized, parallel-arm open-label study, we enrolled patients aged ≥18 years with T2DM for at least 6 months and a glycated haemoglobin (HbA1c) concentration ≥53.0 mmol/mol (7.0%) and ≤96.7 mmol/mol (11.0%). The primary outcome was change in HbA1c from baseline to week 26 to determine non-inferiority of dulaglutide 1.5 mg versus glargine. RESULTS: A total of 774 patients from China, South Korea, Mexico and Russia were randomly assigned (1:1:1) to dulaglutide 1.5 mg, dulaglutide 0.75 mg or glargine treatment groups. The patients' mean age was 55 years and the average T2DM duration was ~8 years. The least squares mean (SE) changes from baseline in HbA1c at 26 weeks were - 18.9 (0.73) mmol/mol (-1.73 [0.067]%) for dulaglutide 1.5 mg and -14.5 (0.73) mmol/mol (-1.33 [0.067]%) for dulaglutide 0.75 mg, compared with -12.7 (0.73) mmol/mol (-1.16 [0.067]%) for glargine. Statistical criteria for superiority were met with both dulaglutide 1.5 mg and dulaglutide 0.75 mg. More patients in the dulaglutide 1.5 and 0.75 mg groups achieved HbA1c target <53.0 mmol/mol (<7.0%) than in the glargine group at week 26 (P < 0.001 and P = 0.004, respectively). Body weight decreased with dulaglutide and increased with glargine. The incidence and rate of total hypoglycaemia were lower with dulaglutide versus glargine. Gastrointestinal adverse events, including diarrhoea and nausea, were the most frequently reported for patients taking dulaglutide. CONCLUSIONS: Once-weekly dulaglutide provides greater improvement in HbA1c, with weight loss and less hypoglycaemia, than once-daily insulin glargine in a population of mainly Asian patients with T2DM who had failed to achieve optimal glycaemic control on metformin and/or a sulphonylurea.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Insulina Glargina/administração & dosagem , Metformina/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Compostos de Sulfonilureia/administração & dosagem , Adulto , Idoso , Povo Asiático/estatística & dados numéricos , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , China/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etnologia , Esquema de Medicação , Quimioterapia Combinada , Feminino , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Humanos , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Insulina Glargina/efeitos adversos , Masculino , Metformina/efeitos adversos , México/epidemiologia , Pessoa de Meia-Idade , Proteínas Recombinantes de Fusão/efeitos adversos , República da Coreia/epidemiologia , Federação Russa/epidemiologia , Compostos de Sulfonilureia/efeitos adversos , Resultado do Tratamento
9.
Bioconjug Chem ; 29(11): 3810-3816, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30350578

RESUMO

Many strategies for the detection of nucleic acid sequence rely upon Watson-Crick hybridization of a probe strand to the target strand, but the reversible nature of nucleic acid hybridization presents an inherent challenge: short probes that provide high target specificity have relatively low target affinity resulting in signal losses. Sequence-specific covalent cross-linking reactions have the potential to provide both selective target capture and durable signal. We explore a novel approach involving sequence-specific covalent cross-linking of a probe to target DNA combined with single-molecule nanopore detection of the cross-linked DNA. Here, we exploited the selective reaction of mechlorethamine at a C-C mismatch for covalent capture of a target DNA sequence corresponding to a cancer-driving mutation at position 1799 of the human BRAF kinase gene. We then demonstrated that the α-hemolysin protein nanopore can be employed for the unambiguous, single-molecule detection of the cross-linked probe-target complex. Cross-linked DNA generates an unmistakable deep and persistent current block (≥5 s) that is easily distinguished from the microsecond and millisecond blocks generated by translocation of single-stranded DNA and uncross-linked duplexes through the nanopore.


Assuntos
Reagentes de Ligações Cruzadas/química , DNA/química , Mecloretamina/química , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas B-raf/genética , Pareamento Incorreto de Bases , Sequência de Bases , DNA/genética , Proteínas Hemolisinas/química , Humanos , Nanoporos/ultraestrutura , Hibridização de Ácido Nucleico
10.
Diabetes Obes Metab ; 20(9): 2121-2130, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29708650

RESUMO

AIMS: To compare the efficacy and safety of once-weekly glucagon-like peptide-1 receptor agonist dulaglutide 1.5 and 0.75 mg with glimepiride in East-Asian patients with type 2 diabetes (T2D). MATERIALS AND METHODS: In this phase III, multinational, multicentre, double-blind, randomized, parallel-arm, 26-week study, patients with inadequate glycaemic control were randomized 1:1:1 to once-weekly dulaglutide 1.5 or 0.75 mg or daily glimepiride (1-3 mg/d). The primary endpoint was assessment of the non-inferiority of dulaglutide (1.5 mg), as measured by change in glycated haemoglobin (HbA1c), compared with glimepiride using a 0.4% non-inferiority margin. RESULTS: A total of 737 patients were randomized (dulaglutide 1.5 mg, n = 244; dulaglutide 0.75 mg, n = 248; glimepiride, n = 245). At week 26, both doses of dulaglutide were non-inferior and also superior to glimepiride for HbA1c reduction from baseline with a least squares mean difference of -6.34 mmol/mol (95% confidence interval [CI] -8.31, -4.26) or -0.58% (95% CI -0.76, -0.39) for dulaglutide 1.5 mg and -3.50 mmol/mol (95% CI -5.47, -1.42) or -0.32% (95% CI -0.50, -0.13) for dulaglutide 0.75 mg (P < .001). A greater proportion of patients in the dulaglutide 1.5 mg group achieved the HbA1c target of <53 mmol/mol (<7.0%) compared with the glimepiride group (74.1% vs 57.4%; P < .001). The mean body weight decreased (P < .005) and total hypoglycaemia rates were lower (P < .001) in the dulaglutide groups compared with the glimepiride group. The most common drug-related adverse events in both dulaglutide groups (≥5% of patients) included diarrhoea, nausea, increased lipase, decreased appetite, abdominal distension and vomiting. CONCLUSIONS: Dulaglutide (both doses) demonstrated superior glycaemic control vs glimepiride, with a favourable tolerability and safety profile in East-Asian patients with T2D.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Hipoglicemiantes/administração & dosagem , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Compostos de Sulfonilureia/administração & dosagem , Idoso , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Ásia Oriental , Feminino , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes de Fusão/efeitos adversos , Compostos de Sulfonilureia/efeitos adversos , Resultado do Tratamento
11.
Surg Radiol Anat ; 40(6): 609-614, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29079941

RESUMO

PURPOSE: The positional relationship between the mandibular canal and corresponding third molars is a key anatomic factor of inferior alveolar nerve (IAN) injury. The aim of the present study is to classify the anatomic three-dimensional relationship between the mandibular third molar and the mandibular canal on cone-beam computed tomography (CBCT) images. METHODS: This study used CBCT images to classify the positional relationship between the mandibular canal and corresponding third molars. CBCT images of 749 patients (1296 mandibular third molars) were analyzed to draw up a classification. RESULTS: On a total of 1296 third molars, the mandibular canal relative to the roots of the mandibular third molar was on the apical side (88.1%), followed by the buccal side (7.9%), the lingual side (3.5%), and then between the roots (0.5%). Ninety-five (7.1%) third molars had a close relation with the mandibular canal, while 1201 (92.7%) third molars had no direct contact. The percentage of the mandibular canal contacts with the mandibular third molar was higher when the mandibular canal was lingually positioned. CONCLUSIONS: The anatomic structures of the mandibular third molar and the mandibular canal may be helpful to make adequate surgical planning to avoid or reduce nerve involvement.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Mandíbula/anatomia & histologia , Dente Serotino/anatomia & histologia , Adulto , Idoso , Humanos , Imageamento Tridimensional , Mandíbula/diagnóstico por imagem , Nervo Mandibular/anatomia & histologia , Nervo Mandibular/diagnóstico por imagem , Pessoa de Meia-Idade , Dente Serotino/diagnóstico por imagem , Adulto Jovem
12.
Anal Chem ; 89(24): 13039-13043, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29183111

RESUMO

Aerolysin protein pore has been widely used for sensing peptides and proteins. However, only a few groups explored this nanopore for nucleic acids detection. The challenge is the extremely low capture efficiency for nucleic acids (>10 bases), which severely lowers the sensitivity of an aerolysin-based genetic biosensor. Here we reported a simple and easy-to-operate approach to noncovalently transform aerolysin into a highly nucleic acids-sensitive nanopore. Through a remote pH-modulation mechanism, we simply lower the pH on one side of the pore, then aerolysin is immediately "activated" and enabled to capture target DNA/RNA efficiently from the opposite side of the pore. This mechanism also decelerates DNA translocation, a desired property for sequencing and gene detection, allowing temporal separation of DNAs in different lengths. This method provides insight into the nanopore engineering for biosensing, making aerolysin applicable in genetic and epigenetic detections of long nucleic acids.


Assuntos
Toxinas Bacterianas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Nanoporos , Ácidos Nucleicos/análise , Proteínas Citotóxicas Formadoras de Poros/genética , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Concentração de Íons de Hidrogênio , Pulmão/química , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/metabolismo
13.
Chembiochem ; 18(14): 1383-1386, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28422400

RESUMO

Hybridization-based methods for the detection of nucleic acid sequences are important in research and medicine. Short probes provide sequence specificity, but do not always provide a durable signal. Sequence-specific covalent crosslink formation can anchor probes to target DNA and might also provide an additional layer of target selectivity. Here, we developed a new crosslinking reaction for the covalent capture of specific nucleic acid sequences. This process involved reaction of an abasic (Ap) site in a probe strand with an adenine residue in the target strand and was used for the detection of a disease-relevant T→A mutation at position 1799 of the human BRAF kinase gene sequence. Ap-containing probes were easily prepared and displayed excellent specificity for the mutant sequence under isothermal assay conditions. It was further shown that nanopore technology provides a high contrast-in essence, digital-signal that enables sensitive, single-molecule sensing of the cross-linked duplexes.


Assuntos
Sondas Moleculares/química , Nanoporos , Proteínas Proto-Oncogênicas B-raf/genética , Sequência de Bases , Humanos , Mutação , Proteínas Proto-Oncogênicas B-raf/metabolismo
14.
J Am Chem Soc ; 137(50): 15742-52, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26595106

RESUMO

Pseudoknots are a fundamental RNA tertiary structure with important roles in regulation of mRNA translation. Molecular force spectroscopic approaches such as optical tweezers can track the pseudoknot's unfolding intermediate states by pulling the RNA chain from both ends, but the kinetic unfolding pathway induced by this method may be different from that in vivo, which occurs during translation and proceeds from the 5' to 3' end. Here we developed a ribosome-mimicking, nanopore pulling assay for dissecting the vectorial unfolding mechanism of pseudoknots. The pseudoknot unfolding pathway in the nanopore, either from the 5' to 3' end or in the reverse direction, can be controlled by a DNA leader that is attached to the pseudoknot at the 5' or 3' ends. The different nanopore conductance between DNA and RNA translocation serves as a marker for the position and structure of the unfolding RNA in the pore. With this design, we provided evidence that the pseudoknot unfolding is a two-step, multistate, metal ion-regulated process depending on the pulling direction. Most notably, unfolding in both directions is rate-limited by the unzipping of the first helix domain (first step), which is Helix-1 in the 5' → 3' direction and Helix-2 in the 3' → 5' direction, suggesting that the initial unfolding step in either pulling direction needs to overcome an energy barrier contributed by the noncanonical triplex base-pairs and coaxial stacking interactions for the tertiary structure stabilization. These findings provide new insights into RNA vectorial unfolding mechanisms, which play an important role in biological functions including frameshifting.


Assuntos
Conformação de Ácido Nucleico , RNA Ribossômico/metabolismo , Ribossomos/metabolismo , RNA Ribossômico/química
15.
Bioorg Med Chem Lett ; 25(6): 1196-205, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25686852

RESUMO

The design, synthesis and structure-activity relationships of a novel series of 3,4-disubstituted pyrrolidine acid analogs as PPAR ligands is outlined. In both the 1,3- and 1,4-oxybenzyl pyrrolidine acid series, the preferred stereochemistry was shown to be the cis-3R,4S isomer, as exemplified by the potent dual PPARα/γ agonists 3k and 4i. The N-4-trifluoromethyl-pyrimidinyl pyrrolidine acid analog 4i was efficacious in lowering fasting glucose and triglyceride levels in diabetic db/db mice.


Assuntos
Hipoglicemiantes/síntese química , PPAR alfa/agonistas , PPAR gama/agonistas , Pirrolidinas/química , Animais , Glicemia/análise , Diabetes Mellitus Tipo 2/tratamento farmacológico , Desenho de Fármacos , Feminino , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Ligantes , Camundongos , Camundongos Obesos , PPAR alfa/metabolismo , PPAR gama/metabolismo , Pirrolidinas/síntese química , Pirrolidinas/uso terapêutico , Estereoisomerismo , Relação Estrutura-Atividade , Triglicerídeos/sangue
16.
Photodiagnosis Photodyn Ther ; 48: 104245, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871015

RESUMO

BACKGROUND: Anal condyloma acuminatum (CA) is marked by its thorny treatment and high recurrence rate. Although 5-aminolevulinic acid photodynamic therapy (ALA-PDT) demonstrates significant efficacy and safety in treating anal CA, it does not completely prevent recurrence. This study aimed to develop and validate a nomogram model in predicting the risk of relapse in HIV-negative patients with anal CA following treatment with ALA-PDT. METHODS: A retrospective analysis was conducted on patients diagnosed with anal CA who received combined CO2 laser vaporization and ALA-PDT between January 2013 and May 2023. Patients were divided into recurrence and non-recurrence groups. A nomogram was developed based on factors showing statistical significance in multivariable logistic regression analysis. The discriminative ability and clinical utility of the nomogram were assessed via ROC curves and decision curve analysis, with internal validation performed through bootstrap resampling. RESULTS: Among the 176 patients included, 33 (18.75 %) experienced recurrence, while 143 did not. Independent predictors for recurrence included HPV types, history of anal intercourse, and the number of CO2 laser treatments received. Incorporating these predictors, the nomogram demonstrated a superior diagnostic performance (area under the curve = 0.881, 95 % CI: 0.818-0.935) and a significant net benefit in decision curve analysis. CONCLUSIONS: The nomogram accurately predicts the risk of recurrence in HIV-negative patients with anal CA following ALA-PDT. It offers a valuable tool for guiding preoperative clinical decision-making and establishing personalized treatment strategies to minimize the risk of relapse.

17.
JAMA Neurol ; 81(2): 118-125, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38190136

RESUMO

Importance: The effect of argatroban in patients with acute ischemic stroke (AIS) and early neurological deterioration (END) is unknown. Objective: To assess the efficacy of argatroban for END in AIS. Design, Setting, and Participants: This open-label, blinded-end point, randomized clinical trial was conducted from April 4, 2020, through July 31, 2022. The date of final follow-up was October 31, 2022. This was a multicenter trial. Eligible patients were adults with AIS who experienced END, which was defined as an increase of 2 or more points on the National Institutes of Health Stroke Scale within 48 hours from symptom onset. Patients who withdrew consent, experienced duplicate randomization, or were lost to follow-up were excluded from the study. Interventions: Patients were randomly assigned to the argatroban group and control group within 48 hours of symptom onset. Both groups received standard therapy based on guidelines, including oral mono or dual antiplatelet therapy. The argatroban group received intravenous argatroban for 7 days (continuous infusion at a dose of 60 mg per day for 2 days, followed by 20 mg per day for 5 days) in addition to standard therapy. Main Outcome and Measure: The primary end point was good functional outcome at 90 days, defined as a modified Rankin Scale score of 0 to 3. Results: A total of 628 patients (mean [SD] age, 65 [11.9] years; 400 male [63.7%]) were included in this study (argatroban group, 314 [50%] and control group, 314 [50%]). Of these, 18 withdrew consent, 1 had duplicate randomization, and 8 were lost to follow-up. A total of 601 patients with stroke were included in the intention-to-treat analysis. Finally, 564 patients were included in the per-protocol analysis as 6 participants in the argatroban group and 31 participants in the control group did not follow the complete protocol. The number of patients with good functional outcome at 90 days was 240 (80.5%) in the argatroban group and 222 (73.3%) in the control group (risk difference, 7.2%; 95% CI, 0.6%-14.0%; risk ratio, 1.10; 95% CI, 1.01-1.20; P = .04). The proportion of symptomatic intracranial hemorrhage was 3 of 317 (0.9%) in the argatroban group and 2 of 272 (0.7%) in the control group (P = .78). Conclusions and Relevance: Among patients with AIS with END, treatment with argatroban and antiplatelet therapy resulted in a better functional outcome at 90 days. This trial provided evidence to support the use of argatroban in reducing disability for patients with END. Trial Registration: ClinicalTrials.gov Identifier: NCT04275180.


Assuntos
Arginina/análogos & derivados , AVC Isquêmico , Acidente Vascular Cerebral , Sulfonamidas , Adulto , Humanos , Masculino , Idoso , AVC Isquêmico/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Ácidos Pipecólicos/uso terapêutico , Ácidos Pipecólicos/efeitos adversos , Anticoagulantes/uso terapêutico
18.
J Biol Chem ; 287(20): 16890-902, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22461624

RESUMO

Expression of glutathione peroxidase 3 (GPx3) is down-regulated in a variety of human malignancies. Both methylation and deletion of GPx3 gene underlie the alterations of GPx3 expression in prostate cancer. A strong correlation between the down-regulation of GPx3 expression and progression of prostate cancer and the suppression of prostate cancer xenografts in SCID mice by forced expression of GPx3 suggests a tumor suppression role of GPx3 in prostate cancer. However, the mechanism of GPx3-mediated tumor suppression remains unclear. In this report, GPx3 was found to interact directly with p53-induced gene 3 (PIG3). Forced overexpression of GPx3 in prostate cancer cell lines DU145 and PC3 as well as immortalized prostate epithelial cells RWPE-1 increased apoptotic cell death. Expression of GPx3(x73c), a peroxidase-negative OPAL codon mutant, in DU145 and PC3 cells also increased cell death. The induced expression of GPx3 in DU145 and PC3 cells resulted in an increase in reactive oxygen species and caspase-3 activity. These activities were abrogated by either knocking down PIG3 or mutating the PIG3 binding motif in GPx3 or binding interference from a peptide corresponding to PIG3 binding motif in GPx3. In addition, UV-treated RWPE-1 cells underwent apoptotic death, which was partially prevented by knocking down GPx3 or PIG3, suggesting that GPx3-PIG3 signaling is critical for UV-induced apoptosis. Taken together, these results reveal a novel signaling pathway of GPx3-PIG3 in the regulation of cell death in prostate cancer.


Assuntos
Apoptose , Glutationa Peroxidase/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Motivos de Aminoácidos , Animais , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Glutationa Peroxidase/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos SCID , Transplante de Neoplasias , Neoplasias da Próstata/genética , Ligação Proteica/genética , Ligação Proteica/efeitos da radiação , Proteínas Proto-Oncogênicas/genética , Transplante Heterólogo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta
19.
Methods ; 57(1): 40-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22487183

RESUMO

This review article introduces the nanopore single-molecule method for the study of G-quadruplex nucleic acid structures. Single G-quadruplexes can be trapped into a 2 nm protein pore embedded in the lipid bilayer membrane. The trapped G-quadruplex specifically blocks the current through the nanopore, creating a signature event for quantitative analysis of G-quadruplex properties, from cation-determined folding and unfolding kinetics to the interactions with the protein ligand. The nanopore single-molecule method is simple, accurate, and requires no labels. It can be used to evaluate G-quadruplex mechanisms and it may have applications in G-quadruplex-based biosensors, nanomachines, and nanostructure assembly.


Assuntos
Técnicas Biossensoriais , Quadruplex G , Conformação de Ácido Nucleico , Proteínas/química , Cátions , Cinética , Ligantes , Nanoporos , Nanoestruturas , RNA/química , Dobramento de RNA
20.
Proc Natl Acad Sci U S A ; 107(18): 8165-70, 2010 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-20400691

RESUMO

Engineered protein pores have several potential applications in biotechnology: as sensor elements in stochastic detection and ultrarapid DNA sequencing, as nanoreactors to observe single-molecule chemistry, and in the construction of nano- and micro-devices. One important class of pores contains molecular adapters, which provide internal binding sites for small molecules. Mutants of the alpha-hemolysin (alphaHL) pore that bind the adapter beta-cyclodextrin (betaCD) approximately 10(4) times more tightly than the wild type have been obtained. We now use single-channel electrical recording, protein engineering including unnatural amino acid mutagenesis, and high-resolution x-ray crystallography to provide definitive structural information on these engineered protein nanopores in unparalleled detail.


Assuntos
Ciclodextrinas/química , Proteínas Hemolisinas/química , Nanoestruturas/química , Cristalografia por Raios X , Proteínas Hemolisinas/genética , Interações Hidrofóbicas e Hidrofílicas , Cinética , Modelos Moleculares , Mutação , Porosidade , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Termodinâmica
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