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1.
Nat Cancer ; 5(3): 400-419, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38267627

RESUMO

Kirsten rat sarcoma virus (KRAS) signaling drives pancreatic ductal adenocarcinoma (PDAC) malignancy, which is an unmet clinical need. Here, we identify a disintegrin and metalloproteinase domain (ADAM)9 as a modulator of PDAC progression via stabilization of wild-type and mutant KRAS proteins. Mechanistically, ADAM9 loss increases the interaction of KRAS with plasminogen activator inhibitor 1 (PAI-1), which functions as a selective autophagy receptor in conjunction with light chain 3 (LC3), triggering lysosomal degradation of KRAS. Suppression of ADAM9 by a small-molecule inhibitor restricts disease progression in spontaneous models, and combination with gemcitabine elicits dramatic regression of patient-derived tumors. Our findings provide a promising strategy to target the KRAS signaling cascade and demonstrate a potential modality to enhance sensitivity to chemotherapy in PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Proteínas Proto-Oncogênicas p21(ras) , Proliferação de Células , Neoplasias Pancreáticas/tratamento farmacológico , Carcinoma Ductal Pancreático/tratamento farmacológico , Gencitabina , Proteínas de Membrana/metabolismo , Proteínas ADAM/metabolismo , Proteínas ADAM/uso terapêutico
3.
Front Pediatr ; 10: 866391, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874563

RESUMO

Background: The COVID-19 pandemic has highlighted the importance of mental wellbeing. The identification and implementation of quality measures can improve health outcomes and patient experience. The objective was to identify and define a core set of valid and relevant pediatric mental health quality measures that will support health system evaluation and quality improvement in British Columbia, Canada. Methods: The study consisted of four phases. First, a comprehensive database search identified valid pediatric quality measures focused on mental health and substance use (MH/SU). Second, the identified quality measures were mapped to focus areas, which were then prioritized by two stakeholder groups consisting of 26 members. Third, up to two representative measures for each prioritized focus area were pre-selected by an expert panel (n = 9). And fourth, a three-step modified Delphi approach was employed to (1) assess each quality measure on a 7-point Likert scale against three relevance criteria (representative of a quality problem, value to intended audience and actionable), (2) discuss the results, and (3) select and rank the most relevant measures. Forty-eight stakeholders were invited to participate; of those 24 completed the round 1 survey, 21 participated in the round 2 discussion and 18 voted in the round 3 selection and ranking survey. For round 1, consensus was determined when at least 70% of the response rates were within the range of five to seven. For round 3, Kendall's coefficient of concordance W was used as an estimator of inter-rater reliability. Results: One-hundred pediatric mental health quality measures were identified in the database search. Of those, 37 were mapped to ten focus areas. Pre-selection resulted in 19 representative measures moving forward to the Delphi study. Eleven measures met the consensus thresholds and were brought forward to the round 2 discussion. Round 3 ranking showed moderate to strong raters' agreement (Kendall's W = 0.595; p < 0.01) and resulted in the following five highest-ranked measures: level of satisfaction after discharge from inpatient admission due to MH/SU, number of patients experiencing seclusion or restraint, length of time from eating disorder referral to assessment, number of ED visits due to MH/SU, and number of readmissions to ED. Conclusion: The selected core set of valid and relevant pediatric quality measures will support sustainable system change in British Columbia. The five top-ranked measures will be refined and tested for data collection feasibility before being implemented in the province.

4.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563292

RESUMO

During the sustained COVID-19 pandemic, global mass vaccination to achieve herd immunity can prevent further viral spread and mutation. A protein subunit vaccine that is safe, effective, stable, has few storage restrictions, and involves a liable manufacturing process would be advantageous to distribute around the world. Here, we designed and produced a recombinant spike (S)-Trimer that is maintained in a prefusion state and exhibits a high ACE2 binding affinity. Rodents received different doses of S-Trimer (0.5, 5, or 20 µg) antigen formulated with aluminum hydroxide (Alum) or an emulsion-type adjuvant (SWE), or no adjuvant. After two vaccinations, the antibody response, T-cell responses, and number of follicular helper T-cells (Tfh) or germinal center (GC) B cells were assessed in mice; the protective efficacy was evaluated on a Syrian hamster infection model. The mouse studies demonstrated that adjuvating the S-Trimer with SWE induced a potent humoral immune response and Th1-biased cellular immune responses (in low dose) that were superior to those induced by Alum. In the Syrian hamster studies, when S-Trimer was adjuvanted with SWE, higher levels of neutralizing antibodies were induced against live SARS-CoV-2 from the original lineage and against the emergence of variants (Beta or Delta) with a slightly decreased potency. In addition, the SWE adjuvant demonstrated a dose-sparing effect; thus, a lower dose of S-Trimer as an antigen (0.5 µg) can induce comparable antisera and provide complete protection from viral infection. These data support the utility of SWE as an adjuvant to enhance the immunogenicity of the S-Trimer vaccine, which is feasible for further clinical testing.


Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Células Th1 , Adjuvantes Imunológicos/farmacologia , Adjuvantes Farmacêuticos , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/farmacologia , Cricetinae , Emulsões , Humanos , Camundongos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Células Th1/imunologia
5.
JCI Insight ; 7(8)2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35290246

RESUMO

Most therapeutic mAbs target the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2. Unfortunately, the RBD is a hot spot for mutations in SARS-CoV-2 variants, which will lead to loss of the neutralizing function of current therapeutic mAbs. Universal mAbs for different variants are necessary. We identified mAbs that recognized the S2 region of the spike protein, which is identical in different variants. The mAbs could neutralize SARS-CoV-2 infection and protect animals from SARS-CoV-2 challenge. After cloning the variable region of the light chain and heavy chain, the variable region sequences were humanized to select a high-affinity humanized mAb, hMab5.17. hMab5.17 protected animals from SARS-CoV-2 challenge and neutralized SARS-CoV-2 variant infection. We further identified the linear epitope of the mAb, which is not mutated in any variant of concern. These data suggest that a mAb recognizing the S2 region of the spike protein will be a potential universal therapeutic mAb for COVID-19.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Monoclonais , Anticorpos Antivirais , Humanos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
6.
Front Pediatr ; 9: 638070, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095023

RESUMO

Introduction: Adoption of virtual health (VH) solutions in healthcare has been challenging; this changed rapidly after implementation of physical distancing measures due to the COVID-19 pandemic. In response to the pandemic, British Columbia's Children's and Women's sub-specialty hospitals rapidly trained and scaled up support to equip staff and clinicians to use VH. Methods: Ninety-minute live online training workshops and frequently updated online support materials were offered for 6 weeks. Training was monitored via feedback collected at training sessions and a brief post-training survey. After training completion, a second survey was circulated to measure utilization outcomes and experiences with VH. Results: Eight hundred and ninety-five participants representing 82% of staff requiring support were trained through 101 sessions; 348 (38.9%) and 272 (30.4%) responses were collected for the monitoring and outcome surveys, respectively. Overall, 89% agreed that training was relevant to their needs; participants indicated average 58.1% (SD = 26.6) and 60.6% (SD = 25.2) increase in knowledge and confidence in VH after training; 90.1% had booked or conducted VH sessions. Increase in confidence was more pronounced in participants with lesser previous exposure to VH, but number of sessions conducted post-training and percentage of successful sessions were independent of previous exposure. For future training and support, participants suggested subject-tailored trainings, asynchronous trainings, and availability of experienced users. Discussion: Training is key to success of VH implementation. Moving forward, core competencies in VH should be developed to support standardization and allow for evaluation and quality improvement. Incorporation of VH training in continuous professional development and onboarding is also highly recommended.

7.
Int J Ment Health Nurs ; 30 Suppl 1: 1386-1394, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34047043

RESUMO

Anorexia nervosa (AN), which primarily affects adolescent girls and young women, is characterized by excessive dieting, leading to severe weight loss and a pathological fear of becoming overweight, or unhealthy behaviours that hinder weight gain. Caring for patients who have AN is particularly challenging for nursing staff, who are on the front line and have the closest contact with patients. However, little is known about how nursing staff care for adolescent patients with AN in Taiwan. This study aimed to explore nurses' perceptions on and experiences in conflict situations in caring for adolescents with AN. A qualitative study approach was conducted. Through semi-structured interviews, ten nursing staff from the paediatric ward at a university-affiliated medical centre in central Taiwan shared their experiences. Recorded interviews were transcribed and analysed by content analysis. This analysis identified three themes with eight subthemes: (i) struggling to develop therapeutic relationships, (ii) selective focusing, and (iii) difficulty changing minds. The findings of this study indicated a need for ongoing support for nursing staff, the development of therapeutic relationships with adolescent patients with AN, extensive nursing staff preparation, and the development of in-service training programs to enable nursing staff to care for these patients with greater understanding.


Assuntos
Anorexia Nervosa , Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Adolescente , Anorexia Nervosa/terapia , Criança , Feminino , Humanos , Percepção , Pesquisa Qualitativa , Taiwan
8.
Cancer Sci ; 112(5): 1888-1898, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33560542

RESUMO

Circular RNAs (circRNAs) have been identified to exert vital biological functions and can be used as new biomarkers in a number of tumors. However, little is known about the functions of circRNAs in myelodysplastic syndrome (MDS). Here, we aimed to investigate circRNA expression profiles and to investigate the functional and clinical value of circRNAs in MDS. Differential expression of circRNAs between MDS and control subjects was analyzed using circRNA arrays, in which we identified 145 upregulated circRNAs and 224 downregulated circRNAs. Validated by real-time quantitative PCR between 100 MDS patients and 20 controls, three upregulated (hsa_circRNA_100352, hsa_circRNA_104056, and hsa_circRNA_104634) and three downregulated (hsa_circRNA_103846, hsa_circRNA_102817, and hsa_circRNA_102526) circRNAs matched the arrays. The receiver operating characteristic curve analysis of these circRNAs showed that the area under the curve was 0.7266, 0.8676, 0.7349, 0.7091, 0.8806, and 0.7472, respectively. Kaplan-Meier survival analysis showed that only hsa_circRNA_100352, hsa_circRNA_104056, and hsa_circRNA_102817 were significantly associated with overall survival. Furthermore, we generated a competing endogenous RNA network focused on hsa_circRNA_100352, hsa_circRNA_104056, and hsa_circRNA_102817. Analyses using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes showed that the three circRNAs were linked with some important cancer-related functions and pathways.


Assuntos
Biomarcadores Tumorais/metabolismo , Síndromes Mielodisplásicas/metabolismo , RNA Circular/metabolismo , Idoso , Anemia Refratária/genética , Anemia Refratária/metabolismo , Anemia Refratária com Excesso de Blastos/genética , Anemia Refratária com Excesso de Blastos/metabolismo , Anemia Sideroblástica/genética , Anemia Sideroblástica/metabolismo , Área Sob a Curva , Biomarcadores Tumorais/genética , Medula Óssea/metabolismo , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/mortalidade , RNA Circular/genética , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas , Regulação para Cima
9.
Int J Mol Sci ; 21(19)2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33023073

RESUMO

Protein phosphorylation can induce signal transduction to change sperm motility patterns during sperm capacitation. However, changes in the phosphorylation of sperm proteins in mice are still incompletely understood. Here, capacitation-related phosphorylation in mouse sperms were firstly investigated by label-free quantitative (LFQ) phosphoproteomics coupled with bioinformatics analysis using ingenuity pathway analysis (IPA) methods such as canonical pathway, upstream regulator, and network analysis. Among 1632 phosphopeptides identified at serine, threonine, and tyrosine residues, 1050 novel phosphosites, corresponding to 402 proteins, were reported. Gene heatmaps for IPA canonical pathways showed a novel role for GSK-3 in GP6 signaling pathways associated with capacitation for 60 min. At the same time, the reduction of the abundant isoform-specific GSK-3α expression was shown by western blot (WB) while the LFQ pY of this isoform slightly decreased and then increased. The combined results from WB and LFQ methods explain the less inhibitory phosphorylation of GSK-3α during capacitation and also support the predicted increases in its activity. In addition, pAKAP4 increased at the Y156 site but decreased at the Y811 site in a capacitated state, even though IPA network analysis and WB analysis for overall pAKAP revealed upregulated trends. The potential roles of GSK-3 and AKAP4 in fertility are discussed.


Assuntos
Proteínas de Ancoragem à Quinase A/genética , Quinase 3 da Glicogênio Sintase/genética , Proteômica , Capacitação Espermática/genética , Animais , Biologia Computacional , Regulação da Expressão Gênica no Desenvolvimento/genética , Masculino , Camundongos , Fosfoproteínas/genética , Fosforilação/genética , Transdução de Sinais/genética , Espermatozoides/crescimento & desenvolvimento
10.
Artigo em Inglês | MEDLINE | ID: mdl-31540463

RESUMO

A high mortality rate is an issue with acute cerebrovascular disease (ACVD), as it often leads to a high medical expenditure, and in particular to high costs of treatment for emergency medical conditions and critical care. In this study, we used group-based trajectory modeling (GBTM) to study the characteristics of various groups of patients hospitalized with ACVD. In this research, the patient data were derived from the 1 million sampled cases in the National Health Insurance Research Database (NHIRD) in Taiwan. Cases who had been admitted to hospitals fewer than four times or more than eight times were excluded. Characteristics of the ACVD patients were collected, including age, mortality rate, medical expenditure, and length of hospital stay for each admission. We then performed GBTM to examine hospitalization patterns in patients who had been hospitalized more than four times and fewer than or equal to eight times. The patients were divided into three groups according to medical expenditure: high, medium, and low groups, split at the 33rd and 66th percentiles. After exclusion of unqualified patients, a total of 27,264 cases (male/female = 15,972/11,392) were included. Analysis of the characteristics of the ACVD patients showed that there were significant differences between the two gender groups in terms of age, mortality rate, medical expenditure, and total length of hospital stay. In addition, the data were compared between two admissions, which included interval, outpatient department (OPD) visit after discharge, OPD visit after hospital discharge, and OPD cost. Finally, the differences in medical expenditure between genders and between patients with different types of stroke-ischemic stroke, spontaneous intracerebral hemorrhage (sICH), and subarachnoid hemorrhage (SAH)-were examined using GBTM. Overall, this study employed GBTM to examine the trends in medical expenditure for different groups of stroke patients at different admissions, and some important results were obtained. Our results demonstrated that the time interval between subsequent hospitalizations decreased in the ACVD patients, and there were significant differences between genders and between patients with different types of stroke. It is often difficult to decide when the time has been reached at which further treatment will not improve the condition of ACVD patients, and the findings of our study may be used as a reference for assessing outcomes and quality of care for stroke patients. Because of the characteristics of NHIRD, this study had some limitations; for example, the number of cases for some diseases was not sufficient for effective statistical analysis.


Assuntos
Transtornos Cerebrovasculares/economia , Transtornos Cerebrovasculares/epidemiologia , Gastos em Saúde/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/economia , Isquemia Encefálica/epidemiologia , Hemorragia Cerebral/economia , Hemorragia Cerebral/epidemiologia , Transtornos Cerebrovasculares/mortalidade , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde , Fatores Sexuais , Acidente Vascular Cerebral/epidemiologia , Hemorragia Subaracnóidea/economia , Hemorragia Subaracnóidea/epidemiologia , Taiwan/epidemiologia
11.
BMC Med Imaging ; 19(1): 65, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412797

RESUMO

BACKGROUND: Computed tomography pulmonary angiography (CTPA) is the gold standard for the diagnosis of pulmonary embolism (PE). However, contrast is contraindicated in some patients. The purpose of this study was to determine the diagnostic accuracy of unenhanced multidetector CT (MDCT) for diagnosis of central PE using CTPA as the gold standard. METHODS: The records of patients with suspected PE seen between 2010 and 2013 were retrospectively reviewed. Inclusion criteria were an acute, central PE confirmed by CTPA and non-enhanced MDCT before contrast injection. Patients with a PE ruled out by CTPA served as a control group. MDCT findings studied were high-attenuation emboli in pulmonary artery (PA), main PA dilatation > 33.2 mm, and peripheral wedge-shaped consolidation. Receiver operating characteristic (ROC) analysis was used to determine the sensitivity and specificity of unenhanced MDCT to detect PE. Wells score of all patients were calculated using data extracted from medical records prior to imaging analysis. RESULTS: Thirty-two patients with a PE confirmed by CTPA and 32 with a PE ruled out by CTPA were included. Among the three main MDCT findings, high-attenuation emboli in the PA showed best diagnostic performance (Sensitivity 72.9%; Specificity 100%), followed by main PA dilatation > 33.2 mm (sensitivity 46.9%; specificity 90.6%), and peripheral wedge-shaped consolidation (sensitivity 43.8%; specificity 78.1%). Given any one or more positive findings on unenhanced MDCT, the sensitivity was 96.9% and specificity was 71.9% for a diagnosis of PE in patients. The area under the curve (AUC) of a composite measure of unenhanced MDCT findings (0.909) was significantly higher than that of the Wells score (0.688), indicating unenhanced MDCT was reliable for detecting PE than Wells score. CONCLUSIONS: Unenhanced MDCT is an alternative for the diagnosis of acute central PE when CTPA is not available.


Assuntos
Tomografia Computadorizada Multidetectores/métodos , Artéria Pulmonar/patologia , Embolia Pulmonar/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Angiografia por Tomografia Computadorizada , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/patologia , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
Int J Cancer ; 144(11): 2795-2810, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30485433

RESUMO

Oral squamous cell carcinoma (OSCC) LN1-1 cells previously showed greater capacities for lymphangiogenesis and lymph node metastasis compared to their parental OEC-M1 cells, in addition to an ability to enhance the migration and tube formation of lymphatic endothelial cells (LECs). Purified by a series of differential centrifugations and characterized using electron microscopy, dynamic light scattering and western blot, LN1-1 cell-derived extracellular vesicles (LN1-1 EVs) were shown to promote LEC migration, tube formation and uptake by LECs more effectively than did OEC-M1 cell-derived EVs (OEC-M1 EVs). Using stable isotope labeling with amino acids in cell culture/liquid chromatography-tandem mass spectrometry-based proteomic platform, the laminin-332 proteins, including laminin α3, ß3 and γ2, were validated as highly expressed proteins in LN1-1 EVs. Clinically, a higher level of laminin-332 was detected in plasma EVs from OSCC patients with lymph node metastasis than in both healthy controls and OSCC patients without lymphatic metastasis, suggesting EV-borne laminin-332 as a novel and noninvasive biomarker for the detection of lymph node metastasis in OSCC. The knockdown of laminin γ2 and inhibition by anti-laminin-332 neutralizing antibodies impaired LN1-1 EV-mediated LEC migration, tube formation and uptake by LECs. Importantly, laminin γ2-deficient EVs showed a reduced ability to drain into lymph nodes in comparison with the control EVs. In addition, the laminin 332/γ2-mediated EV uptake was dependent on integrin α3 but not ß1, ß4 or α6. Collectively, the uptake of laminin γ2-enriched EVs by LECs enhanced in vitro lymphangiogenesis and EV-borne laminin-332 is thus a viable biomarker for OSCC.


Assuntos
Integrina alfa3/metabolismo , Laminina/metabolismo , Linfangiogênese , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Células Endoteliais/patologia , Vesículas Extracelulares/patologia , Técnicas de Silenciamento de Genes , Humanos , Laminina/genética , Linfonodos/patologia , Metástase Linfática/diagnóstico , Metástase Linfática/patologia , Vasos Linfáticos/citologia , Masculino , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Front Mol Biosci ; 4: 77, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29230394

RESUMO

Lysine acetylation is a prevalent post-translational modification in both eukaryotes and prokaryotes. Whereas this modification is known to play pivotal roles in eukaryotes, the function and extent of this modification in prokaryotic cells remain largely unexplored. Here we report the acetylome of a pair of antibiotic-sensitive and -resistant nosocomial pathogen Acinetobacter baumannii SK17-S and SK17-R. A total of 145 lysine acetylation sites on 125 proteins was identified, and there are 23 acetylated proteins found in both strains, including histone-like protein HU which was found to be acetylated at Lys13. HU is a dimeric DNA-binding protein critical for maintaining chromosomal architecture and other DNA-dependent functions. To analyze the effects of site-specific acetylation, homogenously Lys13-acetylated HU protein, HU(K13ac) was prepared by genetic code expansion. Whilst not exerting an obvious effect on the oligomeric state, Lys13 acetylation alters both the thermal stability and DNA binding kinetics of HU. Accordingly, this modification likely destabilizes the chromosome structure and regulates bacterial gene transcription. This work indicates that acetyllysine plays an important role in bacterial epigenetics.

14.
Sci Rep ; 7(1): 4658, 2017 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-28680127

RESUMO

Billions of tons of keratin bio-wastes are generated by poultry industry annually but discarded that result in serious environmental pollution. Keratinase is a broad spectrum protease with the unique ability to degrade keratin, providing an eco-friendly way to convert keratin wastes to valuable amino acids. In this report, a feather-degrading thermophilic bacterium, Meiothermus taiwanensis WR-220, was investigated due to its ability to apparently complete feather decay at 65 °C in two days. By genomics, proteomics, and biochemical approaches, the extracellular heat-stable keratinase (MtaKer) from M. taiwanensis WR-220 was identified. The recombinant MtaKer (rMtaKer) possesses keratinolytic activities at temperatures ranging from 25 to 75 °C and pH from 4 to 11, with a maximum keratinolytic activity at 65 °C and pH 10. The phylogenetic and structural analysis revealed that MtaKer shares low sequence identity but high structural similarity with known keratinases. Accordingly, our findings have enabled the discovery of more keratinases from other extremophiles, Thermus and Deinococcus. Proteins encoded in the extremophiles shall be evolved to be functional in the extreme conditions. Hence, our study expands the current boundary of hunting keratinases that can tolerate extreme conditions for keratin wastes biorecycle and other industrial applications.


Assuntos
Deinococcus/crescimento & desenvolvimento , Genômica/métodos , Queratinas/química , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Animais , Deinococcus/enzimologia , Deinococcus/genética , Estabilidade Enzimática , Plumas/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Resíduos Industriais , Modelos Moleculares , Peptídeo Hidrolases/química , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Conformação Proteica , Especificidade por Substrato
15.
BMC Microbiol ; 17(1): 123, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28545444

RESUMO

BACKGROUND: Phosphorylation of amino acid residues on proteins is an important and common post-translational modification in both eukaryotes and prokaryotes. Most research work has been focused on phosphorylation of serine, threonine or tyrosine residues, whereas phosphorylation of other amino acids are significantly less clear due to the controversy on their stability under standard bioanalytical conditions. RESULTS: Here we applied a shotgun strategy to analyze the histidine and aspartate phosphorylations in different microbes. Our results collectively indicate that histidine and aspartate phosphorylations frequently occur also in proteins that are not part of the two-component systems. Noticeably, a number of the modified proteins are pathogenesis-related or essential for survival in host. These include the zinc ion periplasmic transporter ZnuA in Acinetobacter baumannii SK17, the multidrug and toxic compound extrusion (MATE) channel YeeO in Klebsiella pneumoniae NTUH-K2044, branched amino acid transporter AzlC in Vibrio vulnificus and the RNA-modifying pseudouridine synthase in Helicobacter pylori. CONCLUSIONS: In summary, histidine and aspartate phosphorylation is likely to be ubiquitous and to take place in proteins of various functions. This work also sheds light into how these functionally important proteins and potential drug targets might be regulated at a post-translational level.


Assuntos
Ácido Aspártico/metabolismo , Resistência a Medicamentos , Histidina/metabolismo , Células Procarióticas/metabolismo , Proteômica/métodos , Acinetobacter baumannii/metabolismo , Aminoácidos/metabolismo , Bactérias/genética , Bactérias/metabolismo , Bactérias/patogenicidade , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Helicobacter pylori/metabolismo , Klebsiella pneumoniae/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Análise de Sequência de Proteína , Vibrio vulnificus/metabolismo , Zinco/metabolismo
16.
Vaccine ; 35(10): 1440-1447, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28190743

RESUMO

Concerns of Acinetobacter baumannii infection have increased due to the emergence of multi-drug resistance. In the present study, we determined the capsular polysaccharide (CPS) structure of A. baumannii SK44, a clinical isolate from Taiwan, to consist of pentasaccharide repeats. We found that CPS-induced antibody provided 55% protection against challenge in an animal model. The CPS-specific antibody reacted with the surface components of about 62% clinical isolates (342/554 strains) from cross-sectional and longitudinal studies by dot-immunoassay. Pulsed-field gel electrophoresis of positive strains showed the antibody covered different clonalites of A. baumannii clinical isolates. Meanwhile, using the CPS antibody as a probe, we found a number of outer membrane proteins bound to the antibody, including OmpA/motB, TonB-dependent receptor, and Omp38, indicating their association with CPS. These results might lead to the use of the capsular polysaccharide as a vaccine to prevent A. baumannii infection.


Assuntos
Infecções por Acinetobacter/prevenção & controle , Acinetobacter baumannii/imunologia , Vacinas Bacterianas/imunologia , Polissacarídeos Bacterianos/imunologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/química , Acinetobacter baumannii/isolamento & purificação , Animais , Vacinas Bacterianas/química , Vacinas Bacterianas/isolamento & purificação , Estudos Transversais , Modelos Animais de Doenças , Humanos , Estudos Longitudinais , Camundongos , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Taiwan
17.
Sci Rep ; 6: 29013, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27357474

RESUMO

Methanogens have gained much attention for their metabolic product, methane, which could be an energy substitute but also contributes to the greenhouse effect. One factor that controls methane emission, reversible protein phosphorylation, is a crucial signaling switch, and phosphoproteomics has become a powerful tool for large-scale surveying. Here, we conducted the first phosphorylation-mediated regulation study in halophilic Methanohalophilus portucalensis FDF1(T), a model strain for studying stress response mechanisms in osmoadaptation. A shotgun approach and MS-based analysis identified 149 unique phosphoproteins. Among them, 26% participated in methanogenesis and osmolytes biosynthesis pathways. Of note, we uncovered that protein phosphorylation might be a crucial factor to modulate the pyrrolysine (Pyl) incorporation and Pyl-mediated methylotrophic methanogenesis. Furthermore, heterologous expression of glycine sarcosine N-methyltransferase (GSMT) mutant derivatives in the osmosensitive Escherichia coli MKH13 revealed that the nonphosphorylated T68A mutant resulted in increased salt tolerance. In contrast, mimic phosphorylated mutant T68D proved defective in both enzymatic activity and salinity tolerance for growth. Our study provides new insights into phosphorylation modification as a crucial role of both methanogenesis and osmoadaptation in methanoarchaea, promoting biogas production or reducing future methane emission in response to global warming and climate change.


Assuntos
Proteínas Arqueais/metabolismo , Metano/biossíntese , Methanosarcinaceae/fisiologia , Osmorregulação/fisiologia , Fosfoproteínas/metabolismo , Processamento de Proteína Pós-Traducional , Sequência de Aminoácidos , Betaína/metabolismo , Aquecimento Global , Glicina N-Metiltransferase/genética , Glicina N-Metiltransferase/metabolismo , Lisina/análogos & derivados , Lisina/metabolismo , Methanosarcinaceae/genética , Metilação , Modelos Moleculares , Mutação de Sentido Incorreto , Fosforilação , Mutação Puntual , Conformação Proteica , Proteômica , Tolerância ao Sal/genética , Tolerância ao Sal/fisiologia , Espectrometria de Massas em Tandem
18.
Mol Cell Proteomics ; 15(1): 12-25, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26499836

RESUMO

Nosocomial infectious outbreaks caused by multidrug-resistant Acinetobacter baumannii have emerged as a serious threat to human health. Phosphoproteomics of pathogenic bacteria has been used to identify the mechanisms of bacterial virulence and antimicrobial resistance. In this study, we used a shotgun strategy combined with high-accuracy mass spectrometry to analyze the phosphoproteomics of the imipenem-susceptible strain SK17-S and -resistant strain SK17-R. We identified 410 phosphosites on 248 unique phosphoproteins in SK17-S and 285 phosphosites on 211 unique phosphoproteins in SK17-R. The distributions of the Ser/Thr/Tyr/Asp/His phosphosites in SK17-S and SK17-R were 47.0%/27.6%/12.4%/8.0%/4.9% versus 41.4%/29.5%/17.5%/6.7%/4.9%, respectively. The Ser-90 phosphosite, located on the catalytic motif S(88)VS(90)K of the AmpC ß-lactamase, was first identified in SK17-S. Based on site-directed mutagenesis, the nonphosphorylatable mutant S90A was found to be more resistant to imipenem, whereas the phosphorylation-simulated mutant S90D was sensitive to imipenem. Additionally, the S90A mutant protein exhibited higher ß-lactamase activity and conferred greater bacterial protection against imipenem in SK17-S compared with the wild-type. In sum, our results revealed that in A. baumannii, Ser-90 phosphorylation of AmpC negatively regulates both ß-lactamase activity and the ability to counteract the antibiotic effects of imipenem. These findings highlight the impact of phosphorylation-mediated regulation in antibiotic-resistant bacteria on future drug design and new therapies.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Imipenem/farmacologia , Proteoma/metabolismo , Proteômica/métodos , beta-Lactamases/metabolismo , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação/genética , Infecção Hospitalar/microbiologia , Humanos , Modelos Moleculares , Mutação , Fosfoproteínas/metabolismo , Fosforilação , Estrutura Terciária de Proteína , Espectrometria de Massas em Tandem , Resistência beta-Lactâmica/efeitos dos fármacos , beta-Lactamases/química , beta-Lactamases/genética
19.
Acta Cardiol Sin ; 31(2): 164-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27122865

RESUMO

UNLABELLED: Primary cardiac tumors are rare. When they do occur, their symptoms and signs depend on the location and size of the tumor. Imaging multimodalities play an important role in evaluating cardiac tumors. "Tumor blush" is a specific character of certain cardiac tumors on coronary angiography. The current treatment of these tumors is associated with observed clinical symptoms, and the main treatment option is surgical resection. Coronary stent grafts have been used for treatment of coronary artery perforation, coronary pseudoaneurysm, and coronary artery fistula. In this article, we presented a 53-year-old woman who had a cardiac tumor with tumor blush complicated by pericardial effusion which was medically managed by use of a stent graft. KEY WORDS: Cardiac neoplasm; Stent graft; Tumor blush.

20.
Mol Cell Proteomics ; 12(10): 2701-13, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23828892

RESUMO

Thermus thermophilus HB27 is an extremely thermophilic eubacteria with a high frequency of natural competence. This organism is therefore often used as a thermophilic model to investigate the molecular basis of type IV pili-mediated functions, such as the uptake of free DNA, adhesion, twitching motility, and biofilm formation, in hot environments. In this study, the phosphoproteome of T. thermophilus HB27 was analyzed via a shotgun approach and high-accuracy mass spectrometry. Ninety-three unique phosphopeptides, including 67 in vivo phosphorylated sites on 53 phosphoproteins, were identified. The distribution of Ser/Thr/Tyr phosphorylation sites was 57%/36%/7%. The phosphoproteins were mostly involved in central metabolic pathways and protein/cell envelope biosynthesis. According to this analysis, the ATPase motor PilF, a type IV pili-related component, was first found to be phosphorylated on Thr-368 and Ser-372. Through the point mutation of PilF, mimic phosphorylated mutants T368D and S372E resulted in nonpiliated and nontwitching phenotypes, whereas nonphosphorylated mutants T368V and S372A displayed piliation and twitching motility. In addition, mimic phosphorylated mutants showed elevated biofilm-forming abilities with a higher initial attachment rate, caused by increasing exopolysaccharide production. In summary, the phosphorylation of PilF might regulate the pili and biofilm formation associated with exopolysaccharide production.


Assuntos
Biofilmes/crescimento & desenvolvimento , Proteínas de Fímbrias/fisiologia , Fímbrias Bacterianas/fisiologia , Fosfoproteínas/fisiologia , Thermus thermophilus/fisiologia , Biopolímeros/metabolismo , Escherichia coli/genética , Fosfopeptídeos/fisiologia , Fosforilação , Polissacarídeos/metabolismo , Proteômica
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