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1.
Chem Sci ; 15(24): 9266-9273, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38903209

RESUMO

The thioether-connected bis-amino acid lanthionine (Lan) residues are class-defining residues of lanthipeptides. Typically, the cyclization step of lanthionine formation, which relies on the addition of a cysteine to an unsaturated dehydroamino acid, is directed either by a standalone cyclase LanC (class I) or by a cyclase domain (class II-IV). However, the pathways of characterized class V members often lack a known cyclase (domain), raising a question on the mechanism by which their multi-macrocycle systems are formed. Herein, we report a new RiPP gene cluster in Streptomyces TN 58, where it encodes the biosynthesis of 3 distinct class V lanthipeptides-termed triantimycins (TAMs). TAM A1∼A3 share an N-terminal ll-MeLan residue, and only TAM A1 contains an additional internal ll-Lan residue. TAM A1 also has a C-terminal (2S, 3R)-S-((Z)-2-aminovinyl)-3-methyl-d-cysteine (alloAviMeCys) residue, which is distinct from the previously reported (2S, 3S)-AviMeCys residue in other RiPPs. Gene deletion, heterologous coexpression, and structural elucidation demonstrated that the cyclization for an ll-MeLan formation occurs spontaneously and is independent of any known lanthionine cyclase. This study provides a new paradigm for lanthionine formation and facilitates genome mining and engineering efforts on RiPPs containing (Me)Lan and (allo)Avi(Me)Cys residues.

2.
Zhen Ci Yan Jiu ; 49(3): 324-329, 2024 Mar 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38500331

RESUMO

"Acupuncture Anesthesia in the People's Republic of China: A Trip Report of the American Acupuncture Anesthesia Study Group" (Report for short) is the first extraterritorial systematic investigation and evaluation report in the history of acupuncture anesthesia in China. After Report was released to the public, it has not drawn much attention in China. At the moment when acupuncture anesthesia is extended to perioperative treatment, by reviewing the Report, the differences in understanding acupuncture anesthesia were analyzed from a foreign perspective. Report involves the clinical observation of surgery under acupuncture anesthesia, the analysis on the factors of acupuncture anesthesia in therapeutic effects and the relevant mechanisms, and the differences in the research methods and foci on the recognition of acupuncture anesthesia between China and foreign countries. In association with the development of acupuncture anesthesia during the past 65 years and the conclusion in Report, the paper briefly describes the development and perfection of acupuncture anesthesia, the historical verification to the conclusions in Report and the limitations in modern acupuncture anesthesia. It provides some inspiration for the development of acupuncture anesthesia, acupuncture-moxibustion medicine and life science in the future.


Assuntos
Analgesia por Acupuntura , Terapia por Acupuntura , Acupuntura , Moxibustão , Humanos , Estados Unidos , China
3.
Comput Biol Med ; 171: 108174, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38442557

RESUMO

Lung cancer poses a global health challenge, necessitating advanced diagnostics for improved outcomes. Intensive efforts are ongoing to pinpoint early detection biomarkers, such as genomic variations and DNA methylation, to elevate diagnostic precision. We conducted long-read sequencing on cancerous and adjacent non-cancerous tissues from a patient with lung adenocarcinoma. We identified somatic structural variations (SVs) specific to lung cancer by integrating data from various SV calling methods and differentially methylated regions (DMRs) that were distinct between these two tissue samples, revealing a unique methylation pattern associated with lung cancer. This study discovered over 40,000 somatic SVs and over 180,000 DMRs linked to lung cancer. We identified approximately 700 genes of significant relevance through comprehensive analysis, including genes intricately associated with many lung cancers, such as NOTCH1, SMOC2, CSMD2, and others. Furthermore, we observed that somatic SVs and DMRs were substantially enriched in several pathways, such as axon guidance signaling pathways, which suggests a comprehensive multi-omics impact on lung cancer progression across various biological investigation levels. These datasets can potentially serve as biomarkers for early lung cancer detection and may hold significant value in clinical diagnosis and treatment applications.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/diagnóstico , Metilação de DNA/genética , Adenocarcinoma de Pulmão/genética , Análise de Sequência com Séries de Oligonucleotídeos , Biomarcadores
4.
Brain Sci ; 14(1)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275528

RESUMO

Whereas traditional histology and light microscopy require multiple steps of formalin fixation, paraffin embedding, and sectioning to generate images for pathologic diagnosis, Microscopy using Ultraviolet Surface Excitation (MUSE) operates through UV excitation on the cut surface of tissue, generating images of high resolution without the need to fix or section tissue and allowing for potential use for downstream molecular tests. Here, we present the first study of the use and suitability of MUSE microscopy for neuropathological samples. MUSE images were generated from surgical biopsy samples of primary and metastatic brain tumor biopsy samples (n = 27), and blinded assessments of diagnoses, tumor grades, and cellular features were compared to corresponding hematoxylin and eosin (H&E) images. A set of MUSE-treated samples subsequently underwent exome and targeted sequencing, and quality metrics were compared to those from fresh frozen specimens. Diagnostic accuracy was relatively high, and DNA and RNA integrity appeared to be preserved for this cohort. This suggests that MUSE may be a reliable method of generating high-quality diagnostic-grade histologic images for neuropathology on a rapid and sample-sparing basis and for subsequent molecular analysis of DNA and RNA.

5.
BMC Oral Health ; 23(1): 834, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932699

RESUMO

BACKGROUND: To assess the impact of coronavirus disease-2019 (COVID-19) in its outbreak stage (Spring Festival in 2020) on oral emergency services. METHODS: Oral emergency cases in Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, during the Spring Festival after the outbreak of the COVID-19 epidemic in 2020 were collected and compared with those in 2018 and 2019. Electronic medical records including the visited department, age, sex, time, date, region, and diagnosis were collected and analyzed. The results were statistically analyzed using Pearson's Chi-square test and one-way analysis of variance (ANOVA). RESULTS: Compared with that in 2018 and 2019, the total number of patients decreased during the Spring Festival in 2020 (p < 0.001), but the proportions of patients visiting Oral Surgery and Oral, Head, and Neck Oncology Emergency departments increased. The average age of patients increased, and the number of night visits decreased. Toothache diseases involving endodontic and periodontal diseases increased, while the proportion of maxillofacial trauma decreased. The wasn't a linear association between diagnosis or genders (P > 0.001) across years. However, a linear-by-linear association between age groups and years, visited departments and years were observed (P < 0.001). CONCLUSIONS: The study revealed that the transmission of COVID-19 affected the patient population and structure of disease types and oral services in 2020 during the Spring Festival, compared with those in the previous two years. The visits to oral emergency departments and the proportions of patients who were children and adolescents reduced; meanwhile, the percentage of the elderly people increased during the outbreak of COVID-19. The clear trend of age groups and visiting divisions could be used as a marker to reflect the severity of the COVID-19 pandemic. These results may serve as a reference for dental practitioners involved in oral emergency services and to allocate the limited emergency health resources.


Assuntos
COVID-19 , Criança , Adolescente , Humanos , Masculino , Feminino , Idoso , Estudos Retrospectivos , Pandemias , Odontólogos , China/epidemiologia , Papel Profissional
6.
Eur Urol Open Sci ; 57: 30-36, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38020530

RESUMO

Background: Lutetium-177-prostate-specific membrane antigen- 617 (Lu-PSMA) is an effective therapy for metastatic castration-resistant prostate cancer (mCRPC). However, treatment responses are heterogeneous despite stringent positron emission tomography (PET)-based imaging selection criteria. Molecularly based biomarkers have potential to refine patient selection and optimise outcomes. Objective: To identify circulating tumour DNA (ctDNA) features associated with treatment outcomes for men treated with Lu-PSMA. Design setting and participants: ctDNA from men treated with Lu-PSMA in combination with idronoxil for progressive mCRPC were analysed using an 85-gene customised sequencing assay. ctDNA fractions, molecular profiles, and the presence of alterations in aggressive-variant prostate cancer (AVPC) genes were analysed at baseline, cycle 3 and at disease progression. Intervention: Men received Lu-PSMA with idronoxil every 6 wk for up to six cycles. Outcome measurements and statistical analysis: Baseline and exit PSMA and fluorodeoxyglucose PET/computed tomography (CT) imaging was conducted at baseline and study exit. Single-photon emission CT (SPECT) scans were performed 24 h after Lu-PSMA. Blood samples were collected at baseline,cycle 3 and at disease progression. Cox proportional-hazards models were used to assess associations and derive hazard ratios (HRs) and confidence intervals (CIs) for associations between molecular factors, imaging features, and clinical outcomes. Results and limitations: Sixty samples from 32 men were sequenced (32 at baseline, 24 at cycle 3, four from patients with disease progression); two samples (baseline, on-treatment) from one individual were excluded from analysis owing to poor quality of the baseline sequencing data. Alterations in AVPC genes were associated with shorter prostate-specific antigen (PSA) progression-free survival (PFS) and overall survival (OS) in univariate (HR 3.4, 95% CI 1.5-7.7; p = 0.0036; and HR 3.3, 95% CI 1.4-7.7; p = 0.0063, respectively) and multivariate analyses (HR 4.8, 95% CI 1.8-13; p = 0.0014; and HR 4.1, 95% CI 1.6-11; p = 0.004). Conclusions: ctDNA alterations in AVPC genes were associated with shorter PSA PFS and OS among men treated with Lu-PSMA and intermittent idronoxil. These candidate molecular biomarkers warrant further study to determine whether they have predictive value and potential to guide synergistic combination strategies to enhance outcomes for men treated with Lu-PSMA for mCRPC. Patient summary: Certain DNA/gene changes detected in the blood of men with advanced prostate cancer were associated with shorter benefit from lutetium PSMA, a targeted radioactive therapy. This information may be useful in determining which men may benefit most from this treatment, but additional research is needed.

7.
Sci China Life Sci ; 65(9): 1811-1823, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35437648

RESUMO

The Revised International Staging System (R-ISS) is a simple and powerful prognostic tool for multiple myeloma (MM). However, heterogeneity in R-ISS stage is still poorly characterised, hampering improvement of treatments. We used single-cell RNA-seq to examine novel cellular heterogeneity and regular networks in nine MM patients stratified by R-ISS. Plasma cells were clustered into nine groups (P1-P9) based on gene expression, where P1-P5 were almost enriched in stage III.PDIA6 was significantly upregulated in P3 and LETM1 was enriched in P1, and they were validated to be upregulated in the MM cell line and in 22 other patients' myeloma cells. Furthermore, in progression, PDIA6 was newly found and verified to be activated by UQCRB through oxidative phosphorylation, while LETM1 was activated by STAT1 via the C-type lectin receptor-signalling pathway. Finally, a subcluster of monocytes was exclusively found in stage III specifically expressed chemokines modulated by ATF3. A few ligand-receptor pairs (CCL3/CCL5/CCL3L1-CCR1) were obviously active in monocyte-plasma communications in stage III. Herein, this study identified novel molecules, networks and crosstalk pairs in different R-ISS stages of MM, providing significant insight for its prognosis and treatment.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/terapia , Estadiamento de Neoplasias
8.
Front Pharmacol ; 13: 1059930, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36712661

RESUMO

Objective: We aimed to explore a new method to reverse early relapse in patients with AML1-ETO-positive acute myeloid cell transplantation. Methods: A chidamide-based 3-drug combination regimen was used in our center to treat patients with AML1-ETO-positive AML post transplantation but negative flow cytometry results. A retrospective analysis was performed of the survival rate and possible influencing factors of patients with relapse treated with this regimen in our center from January 2018 to January 2022. Results: The overall response rate was 95.8% (23/24), and the median number of treatment courses was 4 (range, 3-12 courses). The total molecular complete response (MCR) was 79.1% (19/24) after all treatments, and the molecular complete response was 37.5% (9/24) after one cycle of treatment but reached 58.3% (14/24) after four cycles; overall, the proportion of MCR increased gradually with the increase in treatment cycles. The projected 5-year overall survival rate was 73.9%. The projected 5-year leukemia-free survival rate was 64.8%, and the projected 1-year cumulative relapse rate was 35.5%. The incidence of grade II-IV graft-versus-host diseases (GVHD) was 29.2% (7/24), and that of grade III-IV GVHD was 20.8% (5/24), which could be effectively controlled by glucocorticoid therapy combined with calcineurin inhibitors The total incidence of chronic GVHD was 29.2% (7/24), and all cases were localized chronic GVHD. The total infection rate was 33.3% (8/24), mainly involving bacterial and fungal infections, and the incidence of life-threatening infections was 4.17% (1/24). The treatment-related mortality rate was 0%; and the total mortality rate was 20.8% (5/24). Nausea and vomiting, thrombocytopenia, and neutropenia were common adverse reactions, all of which were Common Terminology Criteria for Adverse Events grade 2-3 events and reversible after drug withdrawal. In terms of immunity, Th1 cell counts gradually increased, Th17 cell counts gradually decreased, and the Th1/Th17 ratio gradually increased after treatment. The CD8+ T lymphocyte count increased gradually, while the CD4+ T lymphocyte count did not change significantly. Conclusion: Our chidamide-based 3-drug combination regimen led to a high remission rate and tolerable adverse reactions in patients with AML1-ETO-positive post-transplant relapse, and most patients can achieve long-term survival with this regimen.

9.
Org Biomol Chem ; 19(30): 6638-6643, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34195739

RESUMO

Fusarium graminearum is a major fungal pathogen that causes a series of devastating crop diseases by producing a variety of mycotoxins. Fusarins are a class of polyketide-nonribosomal peptide hybrids. In Fusarium mycotoxins, a variable 2-pyrrolidone ring conjugates with a polyene chain substituted with a methyl ester moiety. The enzymatic route through which fusarin A, a major member of the fusarin family with a characteristic tetrohydrofuran-coupled pyrrolidone ring, is formed in F. graminearum has not been established. By targeting the final step in the biosynthesis of fusarin A, we report here an S-adenosyl methionine-dependent carboxyl methyltransferase responsible for the formation of the methyl ester moiety by in vivo gene inactivation, isolation and characterization of a key fusarin intermediate, and in vitro biochemical characterization. Related findings provide insights into the poorly understood biosynthetic pathway of fusarin A. Additionally, bioactivity assays demonstrate that the methyl ester is necessary for fusarin cytotoxicity.


Assuntos
Fusarium
10.
J Am Chem Soc ; 142(18): 8454-8463, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32293883

RESUMO

Sulfomycins are sulfur-rich, ribosomally synthesized, and post-translationally modified peptides (RiPPs) that are characterized by a 35-membered macrocyclic ring system with a pyridine domain central to five azoles and additional dehydroamino acids. The pathway through which these large thiopeptide antibiotics are formed in Streptomyces viridochromogene remains elusive. Starting with the cloning of the biosynthetic gene cluster of sulfomycins, we here dissect a two-stage process in which an unusual dehydrogenase heterotrimer functions with two distinct YcaO proteins to install five azole heterocycles into the core peptide sequence of the precursor peptide. The first stage involves the activity of a typical cyclodehydratase complex composed of a didomain E1-YcaO protein and an F-protein partner to heterocyclize distant residues l-Cys2 and l-Thr9 and then the activity of the heterotrimeric dehydrogenase complex that converts the resulting azolines to azoles. In the second stage, this dehydrogenase complex associates with a discrete YcaO protein to form an atypical, four-component azole synthase complex, which is capable of sequentially converting residues l-Cys7, l-Thr5, and l-Ser12 to azoles in a distinct manner. During this process, an E1-like partner protein plays a critical role and functions through the two stages to mediate a variety of specific protein-protein interactions. This partner protein participates in the formation of the active dehydrogenase heterotrimer and the engagement of discrete YcaO activity to form the azole synthase heterotetramer. The findings in this study advance the understanding in the biosynthesis of different azole-containing RiPPs and set the stage for the discovery, engineering, and creation of new thiopeptides using genome mining and synthetic biology approaches.


Assuntos
Azóis/metabolismo , Proteínas de Bactérias/metabolismo , Oxirredutases/metabolismo , Peptídeos/metabolismo , Compostos de Sulfidrila/metabolismo , Azóis/química , Proteínas de Bactérias/química , Estrutura Molecular , Oxirredutases/química , Peptídeos/química , Streptomyces/enzimologia , Compostos de Sulfidrila/química
11.
Sci Rep ; 9(1): 17052, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745186

RESUMO

Next generation sequencing has revolutionised genomic studies of cancer, having facilitated the development of precision oncology treatments based on a tumour's molecular profile. We aimed to develop a targeted gene sequencing panel for application to disparate cancer types with particular focus on tumours of the head and neck, plus test for utility in liquid biopsy. The final panel designed through Roche/Nimblegen combined 451 cancer-associated genes (2.01 Mb target region). 136 patient DNA samples were collected for performance and application testing. Panel sensitivity and precision were measured using well-characterised DNA controls (n = 47), and specificity by Sanger sequencing of the Aryl Hydrocarbon Receptor Interacting Protein (AIP) gene in 89 patients. Assessment of liquid biopsy application employed a pool of synthetic circulating tumour DNA (ctDNA). Library preparation and sequencing were conducted on Illumina-based platforms prior to analysis with our accredited (ISO15189) bioinformatics pipeline. We achieved a mean coverage of 395x, with sensitivity and specificity of >99% and precision of >97%. Liquid biopsy revealed detection to 1.25% variant allele frequency. Application to head and neck tumours/cancers resulted in detection of mutations aligned to published databases. In conclusion, we have developed an analytically-validated panel for application to cancers of disparate types with utility in liquid biopsy.


Assuntos
Carcinoma Ductal Pancreático/genética , Predisposição Genética para Doença/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias Pancreáticas/genética , Neoplasias Hipofisárias/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , DNA Tumoral Circulante/genética , Biologia Computacional/métodos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Biópsia Líquida , Medicina de Precisão/métodos , Sensibilidade e Especificidade
12.
Clin Neuroradiol ; 29(2): 243-251, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29318352

RESUMO

PURPOSE: The hand knob area is the cortical representation of motor hand function. The current study aimed to investigate the effects of eloquent area gliomas on the morphometry of the hand motor cortex and preoperative hand motor function. METHODS: A retrospective study of 320 glioma patients was conducted. Seventy-eight patients with gliomas involving motor functional area were finally enrolled. Using axial T2-weight magnetic resonance images, the width and height of the hand knob were measured in both hemispheres, and differences were compared between the affected and unaffected hemispheres. Receiver operating characteristic (ROC) curve and logistic regression analysis were used to estimate the degree of correlation between distance measurements and motor impairment. RESULTS: The width and height of the hand knob in the affected and unaffected hemispheres were significantly different (p < 0.0001). The width, height and distance from the tumor to hand knob were reduced in the functionally impaired group compared to the unimpaired group (p = 0.0003, p < 0.0001, p = 0.0005, respectively). The three parameters were significantly correlated and remained significant in ROC and logistic regression analysis. The optimal cut-off value of width, height and distance for identifying preoperative hand muscle strength were 5.73 mm, 5.80 mm and 5.92 mm, respectively. CONCLUSION: The morphometry of the hand knob is often changed by the infiltration or extrusion of the tumors that were located in or near the hand knob. The width, height of hand knob and the distance from tumor to hand knob could serve as anatomic biomarkers related to preoperative neurological motor deficits.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Glioma/fisiopatologia , Mãos/fisiologia , Córtex Motor/fisiologia , Adulto , Neoplasias Encefálicas/patologia , Feminino , Glioma/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Córtex Motor/patologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Estudos Retrospectivos
13.
Shanghai Kou Qiang Yi Xue ; 26(4): 368-373, 2017 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-29199328

RESUMO

PURPOSE: To investigate the expression of human ß-defensin(HBD) in human dental pulp tissue and to explore the regulation of HBD in pulp inflammation and the relationship among HBD family members. METHODS: The gene expression of HBD in human dental pulp tissue was assessed in NCBI GEO profiles and was verified by RT-PCR. Human dental pulp cells were stimulated with TNF-α, IL-1α, IL-1ß and IL-6 in different combinations and the expression of HBD2 was analyzed by qPCR. Human dental pulp cells were pretreated with HBD110 and then stimulated with LPS and the expression of TNF-α,IL-1α and HBD2 were analyzed by qPCR. GraphPad Prism 5.01 was used to analyze the results of the experimental and the control groups. RESULTS: 27 HBDs were found to express in human dental pulp tissue in NCBI GEO Profiles. The joint overexpression of TNF-α, IL-1α, IL-1ß and IL-6 increased the expression of HBD2; HBD110 increased the expression of HBD2 by increasing the expression of TNF-α and IL-1α. CONCLUSIONS: Many other HBDs have positive expression in human dental pulp issue besides of HBD1, HBD2, HBD3, HBD4 and the inflammation factors and other HBDs can regulate the expression of HBD2 in dental pulp.


Assuntos
Polpa Dentária , Inflamação , beta-Defensinas , Células Cultivadas , Citocinas/metabolismo , Polpa Dentária/imunologia , Células Epiteliais , Humanos , Interleucina-1beta , Fator de Necrose Tumoral alfa , beta-Defensinas/metabolismo
14.
Exp Cell Res ; 349(2): 221-229, 2016 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-27669641

RESUMO

Adipose derived stem cells (ADSCs) are an important source of stem cells for tissue repair and regeneration; therefore, understanding the mechanisms that regulate stem cell differentiation into a specific lineage is critical. The NF-E2-related factor 2 (Nrf2) pathway and autophagy promote cell survival in response to oxidative stress. However, the roles of Nrf2 and autophagy in bone metabolism under oxidative stress are controversial. Here, we explored the involvement of Nrf2 signaling and autophagy on the differentiation of ADSCs under conditions of oxidative stress. Exposure of ADSCs to H2O2 promoted reactive oxygen species (ROS) accumulation concomitant with the reduction of cell viability, upregulation of Nrf2, the induction of apoptosis and autophagy, and the promotion of osteogenesis. Suppression of autophagic activity at particular stages resulted in the activation of the Nrf2 pathway, whereas osteoblastic differentiation of ADSCs was inhibited upon ROS stimulation. Silencing of Nrf2 promoted autophagy and osteoblastic differentiation upon ROS stimulation in vitro, and this effect was confirmed in vivo in a mouse model, in which bone formation was enhanced in mice receiving Nrf2-knockdown ADSCs. Taken together, these findings indicate that a negative interaction between the Nrf2 pathway and autophagy may modulate oxidative stress-induced ADSC osteogenesis, and suggest that Nrf2 is a potential target to regulate the differentiation of ADSCs into a specific lineage.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Osteogênese/efeitos dos fármacos , Tecido Adiposo/citologia , Animais , Regulação para Baixo , Peróxido de Hidrogênio/farmacologia , Células-Tronco Mesenquimais/citologia , Camundongos Nus , Fator 2 Relacionado a NF-E2/genética , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
PLoS One ; 11(8): e0159946, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27494172

RESUMO

Rhythmic incremental growth lines and the presence of melatonin receptors were discovered in tooth enamel, suggesting possible role of circadian rhythm. We therefore hypothesized that circadian rhythm may regulate enamel formation through melatonin receptors. To test this hypothesis, we examined expression of melatonin receptors (MTs) and amelogenin (AMELX), a maker of enamel formation, during tooth germ development in mouse. Using qRT-PCR and immunocytochemistry, we found that mRNA and protein levels of both MTs and AMELX in normal mandibular first molar tooth germs increased gradually after birth, peaked at 3 or 4 day postnatal, and then decreased. Expression of MTs and AMELX by immunocytochemistry was significantly delayed in neonatal mice raised in all-dark or all-light environment as well as the enamel development. Furthermore, development of tooth enamel was also delayed showing significant immature histology in those animals, especially for newborn mice raised in all daylight condition. Interestingly, disruption in circadian rhythm in pregnant mice also resulted in delayed enamel development in their babies. Treatment with melatonin receptor antagonist 4P-PDOT in pregnant mice caused underexpression of MTs and AMELX associated with long-lasting deficiency in baby enamel tissue. Electromicroscopic evidence demonstrated increased necrosis and poor enamel mineralization in ameloblasts. The above results suggest that circadian rhythm is important for normal enamel development at both pre- and postnatal stages. Melatonin receptors were partly responsible for the regulation.


Assuntos
Ritmo Circadiano/fisiologia , Esmalte Dentário/metabolismo , Dente Molar/metabolismo , Ameloblastos/citologia , Ameloblastos/metabolismo , Amelogenina/genética , Amelogenina/metabolismo , Animais , Animais Recém-Nascidos , Ritmo Circadiano/efeitos da radiação , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/crescimento & desenvolvimento , Proteínas do Esmalte Dentário/genética , Feminino , Imuno-Histoquímica , Luz , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Dente Molar/patologia , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Melatonina/antagonistas & inibidores , Receptores de Melatonina/genética , Receptores de Melatonina/metabolismo , Tetra-Hidronaftalenos/farmacologia , Germe de Dente/metabolismo , Germe de Dente/patologia
16.
Mol Genet Metab ; 116(3): 178-86, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26318253

RESUMO

Asparagine Synthetase Deficiency is a recently described cause of profound intellectual disability, marked progressive cerebral atrophy and variable seizure disorder. To date there has been limited functional data explaining the underlying pathophysiology. We report a new case with compound heterozygous mutations in the ASNS gene (NM_183356.3:c. [866G>C]; [1010C>T]). Both variants alter evolutionarily conserved amino acids and were predicted to be pathogenic based on in silico protein modelling that suggests disruption of the critical ATP binding site of the ASNS enzyme. In patient fibroblasts, ASNS expression as well as protein and mRNA stability are not affected by these variants. However, there is markedly reduced proliferation of patient fibroblasts when cultured in asparagine-limited growth medium, compared to parental and wild type fibroblasts. Restricting asparagine replicates the physiology within the blood-brain-barrier, with limited transfer of dietary derived asparagine, resulting in reliance of neuronal cells on intracellular asparagine synthesis by the ASNS enzyme. These functional studies offer insight into the underlying pathophysiology of the dramatic progressive cerebral atrophy associated with Asparagine Synthetase Deficiency.


Assuntos
Asparagina/metabolismo , Aspartato-Amônia Ligase/deficiência , Aspartato-Amônia Ligase/genética , Proliferação de Células , Mutação , Trifosfato de Adenosina/metabolismo , Aspartato-Amônia Ligase/química , Aspartato-Amônia Ligase/metabolismo , Sítios de Ligação , Células Cultivadas , Simulação por Computador , Meios de Cultura/química , Exoma , Feminino , Fibroblastos/patologia , Humanos , Deficiência Intelectual/etiologia , Deficiência Intelectual/genética , Masculino , Análise de Sequência de DNA
17.
Appl Microbiol Biotechnol ; 99(18): 7663-71, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25967656

RESUMO

Human enterovirus 71 (EV71) infection has emerged as a major threat to children; however, no effective antiviral treatment or vaccine is currently available. Antibody-based treatment shows promises to control this growing public health problem of EV71 infection, and a few potent monoclonal antibodies (mAbs) targeting viral capsid protein have been well described. Here, we generated an EV71-specific mouse mAb 2G8 that conferred full protection against lethal EV71 challenge in a suckling mouse model. 2G8 belonged to IgM isotype and neutralized EV71 at the attachment stage. Biochemical assays mapped the binding epitope of 2G8 to the SP70 peptide, which spanning amino acid residues 208-222 on the VP1 protein. Alanine scanning mutagenesis defined the essential roles of multiple residues, including Y208, T210, G212, K215, K218, L220, E221, and Y222, for 2G8 binding. Then, a panel of single mutation was individually introduced into the EV71 infectious clone by reverse genetics, and three mutant viruses, K215A, K218A, and L220A, were successfully recovered and characterized. Biochemical and neutralization assays revealed that K218A mutant partially escaped 2G8 neutralization, while L220A completely abolished 2G8 binding and neutralization. In particular, neutralization assays with human sera demonstrated that K218A and L220A substitutions are also critical for antibody neutralization in natural infection population. These findings not only generate a protective mAb candidate with therapeutic potential but also provide insights into antibody-mediated EV71 neutralization mechanism.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Enterovirus Humano A/imunologia , Infecções por Enterovirus/terapia , Substituição de Aminoácidos , Animais , Animais Recém-Nascidos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/isolamento & purificação , Análise Mutacional de DNA , Modelos Animais de Doenças , Enterovirus Humano A/genética , Evasão da Resposta Imune , Imunização Passiva , Imunoglobulina M/imunologia , Imunoglobulina M/isolamento & purificação , Imunoglobulina M/uso terapêutico , Camundongos , Testes de Neutralização , Ligação Proteica , Genética Reversa , Análise de Sobrevida , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/imunologia
18.
Int J Clin Exp Med ; 8(2): 1604-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25932089

RESUMO

Inflammatory myofibroblastic tumors (IMT) rarely affect the head and neck region. IMTs of the head and neck regions account for 14-18% of extra-pulmonary IMTs. Most commonly, they are located in the region of the orbits and upper airways, and less often at other sites. In the present study, we reviewed the English-language literature regarding the etiology, clinical features, diagnosis, treatment, and prognosis of IMTs of the head and neck.

19.
Acta Trop ; 145: 1-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25661801

RESUMO

The Xinjiang Uyghur Autonomous Region in northwest China is one of the world's most important foci for cystic echinococcosis. Domestic dogs are the main source for human infection, and previous studies in Xinjiang have found a canine Echinococcus spp. coproELISA prevalence of between 36% and 41%. In 2010 the Chinese National Echinococcosis Control Programme was implemented in Xinjiang, and includes regular dosing of domestic dogs with praziquantel. Six communities in Hobukesar County, northwest Xinjiang were assessed in relation to the impact of this control programme through dog necropsies, dog Echinococcus spp. coproantigen surveys based on Lot Quality Assurance Sampling (LQAS) and dog owner questionnaires. We found that 42.1% of necropsied dogs were infected with Echinococcus granulosus, and coproELISA prevalences were between 15% and 70% in the communities. Although approximately half of all dog owners reported dosing their dogs within the 12 months prior to sampling, coproELISA prevalence remained high. Regular praziquantel dosing of owned dogs in remote and semi-nomadic communities such as those in Hobukesar County is logistically very difficult and additional measures should be considered to reduce canine echinococcosis.


Assuntos
Doenças do Cão/tratamento farmacológico , Doenças do Cão/epidemiologia , Equinococose/epidemiologia , Equinococose/veterinária , Echinococcus granulosus/efeitos dos fármacos , Praziquantel/uso terapêutico , Zoonoses/prevenção & controle , Animais , China/epidemiologia , Cães , Equinococose/tratamento farmacológico , Humanos , Amostragem para Garantia da Qualidade de Lotes , Prevalência , Inquéritos e Questionários
20.
Cell Physiol Biochem ; 33(5): 1579-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24854846

RESUMO

BACKGROUND/AIMS: RECQL1, a member of the human RECQ helicase family, participates in DNA repair. Recent reports showed that RECQL1 silencing in cancer cells resulted in mitotic catastrophe, which prevented tumor growth in murine models. However, its therapeutic potential has never been examined in tongue squamous cell carcinoma (SCC). METHODS: To explore the role of RECQL1 in the development of tongue SCC, we used RNA interference technology to silence RECQL1 in SCC-9 and SCC-15 human tongue SCC cell lines, and to subsequently evaluate its effects both in vitro and in vivo. RESULTS: After RECQL1 was silenced in SCC cells by siRNA, we observed downregulation of RECQL1 mRNA and protein in cancer cells. RECQL1 is one of the predicted miR-203 targets, and we found that miR-203 downregulated the expression of RECQL1 at the post-transcriptional level. RECQL1-shRNA or miR-203 overexpression inhibited SCC-9 cell growth. In addition, there was accumulation of cells in the sub-G1 fraction and increased apoptosis 72 h post-transfection. In addition, knockdown of RECQL1 led to a strong anticancer effect, as the tumorigenicity of SCC-9 cells was inhibited in vivo. Moreover, we found that two immunosuppressive factors were also significantly downregulated upon RECQL1 knockdown or miR-203 overexpression in vitro. CONCLUSION: Collectively, these results indicate that RECQL1 plays an important regulatory role in cancer cell proliferation and tumor progression.


Assuntos
Carcinoma de Células Escamosas/metabolismo , RecQ Helicases/metabolismo , Neoplasias da Língua/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Inativação Gênica/efeitos dos fármacos , Humanos , Imunossupressores/farmacologia , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , MicroRNAs/metabolismo , RecQ Helicases/antagonistas & inibidores , RecQ Helicases/genética , Relação Estrutura-Atividade , Neoplasias da Língua/tratamento farmacológico , Neoplasias da Língua/patologia
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