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1.
Med Eng Phys ; 102: 103782, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35346436

RESUMO

The commonly used metallic biomaterials fail to prove durability for orthopedics due to their lack of biocompatibility and poor bioactivity which weakens the bonding to bones. Metallic glasses (MGs) have attracted attention as an alternative biomaterial for orthopedics owing to their superior mechanical properties and acceptable biocompatibility. Nevertheless, their uses are limited due to geometrical constraints and brittleness. In this research, the in-vitro bioactivity of laser cladded FeCrMoCB MG on nickel-free stainless-steel was investigated. The proposed MG coating exhibited a remarkable in-vitro bioactivity behavior without prior treatment after immersion in simulated body fluid which is a key factor for better osseointegration. The surface morphology showed that apatite nucleated from the first day and completely covered the surface after 21 days. The energy dispersive spectroscopy spectra showed an increase in the Ca/P ratio from 0.51 at 3 days to 1.61 at 21 days, thus approaching the stoichiometric ratio of bone apatite. The infra-red examination revealed the existence of Ca+2, PO4-2 and OH- indicating the nucleation of brushite and B-type apatite. Additionally, the X-ray diffraction examination revealed the existence of amorphous and nanocrystalline calcium phosphates. These results show the potential of FeCrMoCB MGs as a promising bioactive coating for excellent osseointegration of metallic implants with bone tissue.


Assuntos
Ortopedia , Osseointegração , Apatitas/química , Materiais Biocompatíveis/química , Vidro/química , Lasers
2.
J Gen Intern Med ; 34(10): 2014-2020, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30945065

RESUMO

BACKGROUND: Measuring care coordination in administrative data facilitates important research to improve care quality. OBJECTIVE: To compare shared patient networks constructed from administrative claims data across multiple payers. DESIGN: Social network analysis of pooled cross sections of physicians treating prevalent colorectal cancer patients between 2003 and 2013. PARTICIPANTS: Surgeons, medical oncologists, and radiation oncologists identified from North Carolina Central Cancer Registry data linked to Medicare claims (N = 1735) and private insurance claims (N = 1321). MAIN MEASURES: Provider-level measures included the number of patients treated, the number of providers with whom they share patients (by specialty), the extent of patient sharing with each specialty, and network centrality. Network-level measures included the number of providers and shared patients, the density of shared-patient relationships among providers, and the size and composition of clusters of providers with a high level of patient sharing. RESULTS: For 24.5% of providers, total patient volume rank differed by at least one quintile group between payers. Medicare claims missed 14.6% of all shared patient relationships between providers, but captured a greater number of patient-sharing relationships per provider compared with the private insurance database, even after controlling for the total number of patients (27.242 vs 26.044, p < 0.001). Providers in the private network shared a higher fraction of patients with other providers (0.226 vs 0.127, p < 0.001) compared to the Medicare network. Clustering coefficients for providers, weighted betweenness, and eigenvector centrality varied greatly across payers. Network differences led to some clusters of providers that existed in the combined network not being detected in Medicare alone. CONCLUSION: Many features of shared patient networks constructed from a single-payer database differed from similar networks constructed from other payers' data. Depending on a study's goals, shortcomings of single-payer networks should be considered when using claims data to draw conclusions about provider behavior.


Assuntos
Redes Comunitárias/estatística & dados numéricos , Continuidade da Assistência ao Paciente/estatística & dados numéricos , Estudos de Coortes , Neoplasias Colorretais/terapia , Humanos , Revisão da Utilização de Seguros/estatística & dados numéricos , Medicare/estatística & dados numéricos , North Carolina , Padrões de Prática Médica/estatística & dados numéricos , Sistema de Registros , Estados Unidos
3.
Br J Surg ; 106(3): 190-198, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30724356

RESUMO

BACKGROUND: Whether continued oral feeding may have a negative impact on healing of postoperative pancreatic fistula (POPF) is unclear. The aim was to test the hypothesis that oral feeding is non-inferior to enteral feeding in closure of POPF after pancreatoduodenectomy, and to clarify the effects of oral feeding on the duration and grade of POPF. METHODS: This multicentre, non-inferiority randomized trial of oral or enteral feeding of patients with POPF after pancreatoduodenectomy recruited patients between August 2013 and September 2016. The primary efficacy outcome was the 30-day fistula closure rate. The prespecified non-inferiority margin was 15 per cent. Other efficacy outcomes included grade of fistula, and hospital stay and costs. RESULTS: A total of 114 patients were included, and received oral (57) or enteral (57) feeding. The two groups were balanced in baseline characteristics and no patient was lost to follow-up. In intention-to-treat analysis, oral feeding was non-inferior to enteral feeding in terms of 30-day fistula closure rate (88 versus 89 per cent respectively; difference -1·8 per cent, lower limit of 95 per cent c.i. -14·4 per cent; P = 0·020 for non-inferiority). Compared with enteral feeding, oral feeding significantly reduced hospital costs and duration of stay. No significant differences were noted in the number of patients whose POPF evolved into grade B/C, or other outcomes. CONCLUSION: Oral feeding in patients with POPF after pancreatoduodenectomy did not increase the duration or grade of POPF, and was associated with reduced duration of stay and hospital costs. Registration number: NCT01755260 (http://www.clinicaltrials.gov).


Assuntos
Ingestão de Alimentos , Nutrição Enteral , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
4.
Lupus ; 27(11): 1828-1837, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30134759

RESUMO

Background Cutaneous lupus erythematosus (CLE) includes a broad range of dermatologic manifestations. Periorbital involvement, however, is a relatively rare clinical presentation of CLE. Objectives This clinical study aimed to investigate the characteristics of this unique presentation of CLE in tertiary medical centers. Methods We enrolled patients with periorbital erythema and swelling as the presenting sign of lupus erythematosus, from January 2003 to November 2017, using the data of 553 pathologically proven CLE cases from the registration database of the Chang Gung Memorial Hospitals in Taiwan. Results We enrolled a total of 25 patients. The mean age was 46.7 years and 68% of the patients were female. Most of the patients (84.0%) presented with unilateral involvement, with the left orbit involved in 15 patients (60%); the upper eyelid was the most frequently involved (72%). Mean duration between the onset of clinical manifestations and the diagnosis of CLE was approximately 59 weeks. Nineteen patients had been previously misdiagnosed. All patients had features compatible with CLE on histopathological examination. In contrast, laboratory analysis of the autoimmune profile often revealed negative results, including those for antinuclear antibodies (25%). Notably, anti-SSA/SSB (45.5%) showed the highest positive rate. During follow-up, six patients developed systemic lupus erythematosus (SLE) and two patients developed Sjögren syndrome. Conclusions The diagnosis of CLE presenting as periorbital erythema and swelling is often delayed because of clinical mimicry and the high proportion of negative results on autoantibody tests. Increased clinical suspicion and prompt histopathological examination are crucial for early diagnosis. Moreover, one-fourth of the patients ultimately developed SLE, which highlights the importance of clinical awareness.


Assuntos
Edema/patologia , Eritema/patologia , Lúpus Eritematoso Cutâneo/diagnóstico , Lúpus Eritematoso Cutâneo/patologia , Pele/patologia , Adulto , Idoso , Anticorpos Antinucleares/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan , Centros de Atenção Terciária , Adulto Jovem
5.
Appl Radiat Isot ; 136: 68-72, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29477049

RESUMO

Recurrent groundwater radon anomalies were observed at the Paihe spring (P1) in southwestern Taiwan prior to the Mw 6.3 Jiasian and Mw 6.4 Meinong earthquakes that occurred on March 4, 2010 and February 5, 2016, respectively. Specifically, the concentration of groundwater radon decreased from background levels of 144 ±â€¯7 and 137 ±â€¯8 pCi/L to minima of 104 ±â€¯8 and 97 ±â€¯9 pCi/L prior to the 2010 Jiasian and 2016 Meinong earthquakes, respectively. The Paihe spring (P1) is located 46 km and 45 km, respectively, from the epicenters of the 2010 Mw 6.3 Jiasian and 2016 Mw 6.4 Meinong earthquakes. The above radon anomalies observed at the Paihe limestone spring corroborated that a small fractured aquifer can be used as an effective natural strain meter by applying radon as a tracer for earthquake warning in southwestern Taiwan. There are scientific difficulties and uncertainties in earthquake prediction. Nonetheless, a long-term monitoring of precursory declines in groundwater radon can provide useful data for forecasting local disastrous earthquakes.

6.
Skin Res Technol ; 24(1): 59-64, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28771835

RESUMO

BACKGROUND/PURPOSE: Diffuse reflectance spectroscopy (DRS) is a noninvasive optical technology characterized by relatively low system cost and high efficiency. In our previous study, we quantified the relative concentration of collagen for the individual keloid patient. However, no actual value of collagen concentration can prove the reliability of collagen detection by our DRS system. METHODS: Skin-mimicking phantoms were prepared using different collagen and coffee concentrations, and their chromophore concentrations were quantified using the DRS system to analyze the influence of collagen and other chromophores. Moreover, we used the animal study to compare the DRS system with the collagen evaluation of biopsy section by second-harmonic generation (SHG) microscopy at four different skin parts. RESULTS: In the phantom study, the result showed that coffee chromophore did not severely interfere with collagen concentration recovery. In the animal study, a positive correlation (r=.902) between the DRS system and collagen evaluation with SHG microscopy was found. CONCLUSIONS: We have demonstrated that the DRS system can quantify the actual values of collagen concentration and excluded the interference of other chromophores in skin-mimicking phantoms. Furthermore, a high positive correlation was found in the animal study with SHG microscopy. We consider that the DRS is a potential technique and can evaluate skin condition objectively.


Assuntos
Colágeno/análise , Pele/química , Animais , Biópsia , Humanos , Masculino , Microscopia , Imagens de Fantasmas , Pele/patologia , Análise Espectral/métodos , Suínos , Porco Miniatura
7.
Knee ; 24(6): 1392-1401, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29037743

RESUMO

BACKGROUND: This work aimed to evaluate the efficacy of cartilage transplantation to the medial femoral condyle±platelet-rich fibrin (PRF) augmentation in a porcine model. The hypothesis of the study was that PRF may act as a bioactive cell scaffold to fill defects and enhance cartilage regeneration. METHODS: Thirty-two knees of 16 miniature pigs were randomly assigned to four groups. The critical-size osteochondral defects (8x5mm) in femoral condyle of both knees were treated with one of the following: group 1-untreated controls; group 2-cartilage fragments alone; group 3-PRF alone; group 4-PRFT+cartilage fragments. After completion of the surgical implantation, the periosteal patch harvested from the proximal tibia was sutured onto the cartilage of the medial condyle to cover the implanted defects. Animals were sacrificed at six months after treatment. The regenerated cartilages were assessed by gross inspection and histological examination. RESULTS: The best results were obtained with the repair tissue being hyaline-like cartilage (group 4). The grading score of histological evaluation demonstrated that group 4 had better matrix, cell distribution and cartilage mineralization than group 2 and group 3. PRF showed a positive effect on the cartilage repair; the procedure was more effective when PRF was combined with autologous chondrocytes. CONCLUSIONS: This approach may provide a successfully employed technique to target cartilage defects in vivo. Larger groups and longer periods of study may provide more definitive and meaningful support for using this therapeutic approach as a new way of cartilage regeneration.


Assuntos
Cartilagem/transplante , Condrócitos/transplante , Fêmur/cirurgia , Fibrina Rica em Plaquetas , Animais , Cartilagem/patologia , Cartilagem/fisiologia , Modelos Animais , Periósteo/transplante , Regeneração , Suínos , Tíbia/transplante , Transplante Autólogo
8.
Oncogene ; 36(39): 5484-5496, 2017 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-28534513

RESUMO

Protein disulfide isomerase a4 (PDIA4) is implicated in the growth and death of tumor cells; however, its molecular mechanism and therapeutic potential in cancer are unclear. Here, we found that PDIA4 expression was upregulated in a variety of tumor cell lines and human lung adenocarcinoma tissues. Knockdown and overexpression of PDIA4 in tumor cells showed that PDIA4 facilitated cell growth via the reduction of caspases 3 and 7 activity. Consistently, Lewis lung carcinoma cells overexpressing PDIA4 grew faster than did parental cells in tumor-bearing mice, as shown by a reduced survival rate, increased tumor size and metastasis, and decreased cell death and caspases 3 and 7 activity. PDIA4 knockdown resulted in opposite outcomes. Moreover, results obtained in mice with spontaneous hepatoma indicated that PDIA4 deficiency significantly reduced hepatic tumorigenesis and cyst formation and increased mouse survival, tumor death, and caspases 3 and 7 activity. Mechanistic studies illustrated that PDIA4 negatively regulated tumor cell death by inhibiting degradation and activation of procaspases 3 and 7 via their mutual interaction in a CGHC-dependent manner. Finally, we found that 1,2-dihydroxytrideca-5,7,9,11-tetrayne, a PDIA4 inhibitor, reduced tumor development via enhancement of caspase-mediated cell death in TSA tumor-bearing mice. These findings characterize PDIA4 as a negative regulator of cancer cell apoptosis and suggest that PDIA4 is a potential therapeutic target for cancer.


Assuntos
Caspases/metabolismo , Precursores Enzimáticos/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Células HEK293 , Células Hep G2 , Humanos , Células Jurkat , Células MCF-7 , Masculino , Melanoma Experimental , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
9.
Transl Psychiatry ; 7(2): e1030, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28195570

RESUMO

Global smartphone penetration has led to unprecedented addictive behaviors. To develop a smartphone use/non-use pattern by mobile application (App) in order to identify problematic smartphone use, a total of 79 college students were monitored by the App for 1 month. The App-generated parameters included the daily use/non-use frequency, the total duration and the daily median of the duration per epoch. We introduced two other parameters, the root mean square of the successive differences (RMSSD) and the Similarity Index, in order to explore the similarity in use and non-use between participants. The non-use frequency, non-use duration and non-use-median parameters were able to significantly predict problematic smartphone use. A lower value for the RMSSD and Similarity Index, which represent a higher use/non-use similarity, were also associated with the problematic smartphone use. The use/non-use similarity is able to predict problematic smartphone use and reach beyond just determining whether a person shows excessive use.


Assuntos
Comportamento Aditivo , Comportamento Compulsivo , Smartphone , Estudantes , Coleta de Dados , Feminino , Humanos , Masculino , Aplicativos Móveis , Universidades , Adulto Jovem
10.
Diabetes Obes Metab ; 18 Suppl 1: 117-22, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27615140

RESUMO

Diabetes is caused by a combination of impaired responsiveness to insulin and reduced production of insulin by the pancreas. Until recently, the decline of insulin production had been ascribed to ß-cell death. But recent research has shown that ß-cells do not die in diabetes, but undergo a silencing process, termed "dedifferentiation." The main implication of this discovery is that ß-cells can be revived by appropriate treatments. We have shown that mitochondrial abnormalities are a key step in the progression of ß-cell dysfunction towards dedifferentiation. In normal ß-cells, mitochondria generate energy required to sustain insulin production and its finely timed release in response to the body's nutritional status. A normal ß-cell can adapt its mitochondrial fuel source based on substrate availability, a concept known as "metabolic flexibility." This capability is the first casualty in the progress of ß-cell failure. ß-Cells lose the ability to select the right fuel for mitochondrial energy production. Mitochondria become overloaded, and accumulate by-products derived from incomplete fuel utilization. Energy production stalls, and insulin production drops, setting the stage for dedifferentiation. The ultimate goal of these investigations is to explore novel treatment paradigms that will benefit people with diabetes.


Assuntos
Desdiferenciação Celular , Diabetes Mellitus Tipo 2/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Células Secretoras de Insulina/citologia , Insulina/metabolismo , Animais , Humanos , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Camundongos
11.
Bull Entomol Res ; 106(6): 769-780, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27417424

RESUMO

Chitinases have an indispensable function in chitin metabolism and are well characterized in numerous insect species. Although the diamondback moth (DBM) Plutella xylostella, which has a high reproductive potential, short generation time, and characteristic adaptation to adverse environments, has become one of the most serious pests of cruciferous plants worldwide, the information on the chitinases of the moth is presently limited. In the present study, using degenerated polymerase chain reaction (PCR) and rapid amplification of cDNA ends-PCR strategies, four chitinase genes of P. xylostella were cloned, and an exhaustive search was conducted for chitinase-like sequences from the P. xylostella genome and transcriptomic database. Based on the domain analysis of the deduced amino acid sequences and the phylogenetic analysis of the catalytic domain sequences, we identified 15 chitinase genes from P. xylostella. Two of the gut-specific chitinases did not cluster with any of the known phylogenetic groups of chitinases and might be in a new group of the chitinase family. Moreover, in our study, group VIII chitinase was not identified. The structures, classifications and expression patterns of the chitinases of P. xylostella were further delineated, and with this information, further investigations on the functions of chitinase genes in DBM could be facilitated.


Assuntos
Quitinases/genética , Mariposas/genética , Animais , Domínio Catalítico , Quitina/metabolismo , Quitinases/química , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de Proteína
12.
Neuroscience ; 330: 257-66, 2016 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-27267244

RESUMO

This study aimed to test the hypothesis that, during extended wakefulness, parasympathetic activity is associated with the depth of the subsequent recovery sleep in mice. Fourteen male C57BL/6 mice were implanted with electrodes for sleep recording. Continuous spectral analysis was performed on the electroencephalogram (EEG) to obtain theta power (6-9Hz) and delta power (0-4Hz), as well as the R-R interval signals in order to quantify the high-frequency power (HF) and normalized low-frequency power (LF%) that are used to assess parasympathetic and sympathetic activity, respectively. All animals underwent a sleep deprivation experiment and a control experiment (6-h intervention and 1-h recovery period) on two separate days. During sleep deprivation, HF and theta power during wakefulness were significantly higher than during the control wakefulness after the second hour and first hour, respectively. During recovery non-rapid eye movement sleep, there was a rebound in sleep time and delta power as well as an elevation in HF relative to control post-intervention sleep. Both the rise in HF and theta power during extended wakefulness were found to be positively correlated with the delta power rebound. Furthermore, the HF change during extended wakefulness was also correlated with the amount of sleep loss and the enhancement of waking theta power. Our finding suggests that waking parasympathetic activity intimately reflects the cumulative sleep pressure, suggesting a potential role to be an autonomic marker for sleep propensity.


Assuntos
Encéfalo/fisiopatologia , Frequência Cardíaca/fisiologia , Privação do Sono/fisiopatologia , Sono/fisiologia , Vigília/fisiologia , Animais , Ritmo Delta/fisiologia , Modelos Animais de Doenças , Eletroencefalografia , Masculino , Camundongos Endogâmicos C57BL , Sistema Nervoso Parassimpático/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Ritmo Teta/fisiologia
13.
Pharmacopsychiatry ; 49(5): 191-198, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27023265

RESUMO

Introduction: The autonomic effects of antidepressants and quetiapine on heart rate variability (HRV) are inconsistent based on past studies. The aim of this study was to explore their influence on the HRV of psychiatric patients without psychotic symptoms. Methods: A total of 94 patients with depression, anxiety, or somatic symptoms, were recruited into this study. Based on their medication, 4 groups were identified: the no antidepressant group (n=19), the SSRI group (using sertraline or escitalopram, n=53), the other antidepressants group (using venlafaxine or mirtazapine, n=9), and the augmentation group (AG, using an antidepressant+quetiapine, n=13). The HRV of the 4 groups were compared. The correlations between HRV and the medication(s) used were clarified. Results: Among the 4 groups, the AG had the lowest HRV with its total power (TP), very low frequency power (VLF) and low frequency power (LF) of HRV being significantly different from those of the other groups. Age and using quetiapine were found to be negatively correlated with TP, VLF and LF. With this study group, the autonomic effects of antidepressants were found not to be significant. Discussion: Among psychiatric patients without psychotic symptoms, quetiapine causes an overt decrease in HRV.


Assuntos
Antidepressivos/farmacologia , Depressão/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Fumarato de Quetiapina/farmacologia , Adulto , Idoso , Antidepressivos/uso terapêutico , Ansiedade/tratamento farmacológico , Ansiedade/fisiopatologia , Depressão/tratamento farmacológico , Feminino , Humanos , Modelos Lineares , Masculino , Sintomas Inexplicáveis , Mianserina/análogos & derivados , Pessoa de Meia-Idade , Mirtazapina , Escalas de Graduação Psiquiátrica , Fumarato de Quetiapina/uso terapêutico , Sertralina , Taiwan , Cloridrato de Venlafaxina
14.
Age (Dordr) ; 38(1): 5, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26728397

RESUMO

We hypothesize that the time when age-related changes in autonomic functioning and in sleep structure occur are different and that autonomic functioning modulates sleep architecture differently before and after 50 years of age. Sixty-eight healthy subjects (aged 20 to 79 years old, 49 of them women) were enrolled. Correlation analysis revealed that wake after sleep onset, the absolute and relative value of stage 1 (S1; S1%), and relative value of stage 2 (S2) were positively correlated with age; however, sleep efficiency, stage 3 (S3), S3%, and rapid-eye-movement latency (REML) were negatively correlated with age. Significant degenerations of sleep during normal aging were occurred after 50 years of age; however, significant declines of autonomic activity were showed before 50 years of age. Before 50 years of age, vagal function during sleep was negatively correlated with arousal index; however, after 50 years of age, it was positively correlated with S1 and S1%. In addition, sympathetic activity during wake stage was positively related to S2% only after 50 years of age. Our results imply that the age-related changes in autonomic functioning decline promptly as individuals leave the younger part of their adult life span and that age-related changes in sleep slowly develop as individuals enter the older part of their adult life span. Furthermore, while various aspects of sleep architecture are modulated by both the sympathetic and vagal nervous systems during adult life span, the sleep quality is mainly correlated with the sympathetic division after 50 years of age.


Assuntos
Envelhecimento/fisiologia , Sistema Nervoso Autônomo/fisiologia , Eletrocardiografia , Sono/fisiologia , Adulto , Idoso , Eletroencefalografia , Eletromiografia , Feminino , Seguimentos , Voluntários Saudáveis , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador , Adulto Jovem
15.
Oncogene ; 35(17): 2223-34, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-26411367

RESUMO

Adenomatous polyposis coli (APC), a tumor-suppressor gene critically involved in familial adenomatous polyposis, is integral in Wnt/ß-catenin signaling and is implicated in the development of sporadic tumors of the distal gastrointestinal tract including pancreatic cancer (PC). Here we report for the first time that functional APC is required for the growth and maintenance of pancreatic islets and maturation. Subsequently, a non-Kras mutation-induced premalignancy mouse model was developed; in this model, APC haploinsufficiency coupled with p53 deletion resulted in the development of a distinct type of pancreatic premalignant precursors, mucinous cystic neoplasms (MCNs), exhibiting pathomechanisms identical to those observed in human MCNs, including accumulation of cystic fluid secreted by neoplastic and ovarian-like stromal cells, with 100% penetrance and the presence of hepatic and gastric metastases in >30% of the mice. The major clinical implications of this study suggest targeting the Wnt signaling pathway as a novel strategy for managing MCN.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Pancreáticas/genética , Proteína Supressora de Tumor p53/genética , Animais , Modelos Animais de Doenças , Feminino , Haploinsuficiência/genética , Humanos , Perda de Heterozigosidade , Camundongos , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Pancreáticas/patologia , Via de Sinalização Wnt/genética , Neoplasias Pancreáticas
16.
Leukemia ; 29(11): 2238-47, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25987253

RESUMO

WT1126 (RMFPNAPYL) is a human leukocyte antigen-A2 (HLA-A2)-restricted peptide derived from Wilms tumor protein 1 (WT1), which is widely expressed in a broad spectrum of leukemias, lymphomas and solid tumors. A novel T-cell-receptor (TCR)-like single-chain variable fragment (scFv) antibody specific for the T-cell epitope consisting of the WT1/HLA-A2 complex was isolated from a human scFv phage library. This scFv was affinity-matured by mutagenesis combined with yeast display and structurally analyzed using a homology model. This monovalent scFv showed a 100-fold affinity improvement (dissociation constant (KD)=3 nm) and exquisite specificity towards its targeted epitope or HLA-A2(+)/WT1(+) tumor cells. Bivalent scFv-huIgG1-Fc fusion protein demonstrated an even higher avidity (KD=2 pm) binding to the T-cell epitope and to tumor targets and was capable of mediating antibody-dependent cell-mediated cytotoxicity or tumor lysis by chimeric antigen receptor-expressing human T- or NK-92-MI-transfected cells. This antibody demonstrated specific and potent cytotoxicity in vivo towards WT1-positive leukemia xenograft that was HLA-A2 restricted. In summary, T-cell epitopes can provide novel targets for antibody-based therapeutics. By combining phage and yeast displays and scFv-Fc fusion platforms, a strategy for developing high-affinity TCR-like antibodies could be rapidly explored for potential clinical development.


Assuntos
Afinidade de Anticorpos , Leucemia/terapia , Fragmentos de Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Anticorpos de Cadeia Única/uso terapêutico , Proteínas WT1/imunologia , Animais , Linhagem Celular Tumoral , Mapeamento de Epitopos , Epitopos de Linfócito T , Antígeno HLA-A2/imunologia , Humanos , Células Matadoras Naturais/imunologia , Masculino , Camundongos , Biblioteca de Peptídeos
17.
Int J Obes (Lond) ; 39(8): 1241-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25907313

RESUMO

OBJECTIVES: Mechanisms of the development of abnormal metabolic phenotypes among obese population are not yet clear. In this study, we aimed to screen metabolomes of both healthy and subjects with abnormal obesity to identify potential metabolic pathways that may regulate the different metabolic characteristics of obesity. METHODS: We recruited subjects with body mass index (BMI) over 25 from the weight-loss clinic of a central hospital in Taiwan. Metabolic healthy obesity (MHO) is defined as without having any form of hyperglycemia, hypertension and dyslipidemia, while metabolic abnormal obesity (MAO) is defined as having one or more abnormal metabolic indexes. Serum-based metabolomic profiling using both liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry of 34 MHO and MAO individuals with matching age, sex and BMI was performed. Conditional logistic regression and partial least squares discriminant analysis were applied to identify significant metabolites between the two groups. Pathway enrichment and topology analyses were conducted to evaluate the regulated pathways. RESULTS: A differential metabolite panel was identified to be significantly differed in MHO and MAO groups, including L-kynurenine, glycerophosphocholine (GPC), glycerol 1-phosphate, glycolic acid, tagatose, methyl palmitate and uric acid. Moreover, several metabolic pathways were relevant in distinguishing MHO from MAO groups, including fatty acid biosynthesis, phenylalanine metabolism, propanoate metabolism, and valine, leucine and isoleucine degradation. CONCLUSION: Different metabolomic profiles and metabolic pathways are important for distinguishing between MHO and MAO groups. We have identified and discussed the key metabolites and pathways that may prove important in the regulation of metabolic traits among the obese, which could provide useful clues to study the underlying mechanisms of the development of abnormal metabolic phenotypes.


Assuntos
Glicemia/metabolismo , Inflamação/metabolismo , Obesidade/metabolismo , Adulto , Distribuição da Gordura Corporal , Índice de Massa Corporal , Feminino , Humanos , Inflamação/fisiopatologia , Masculino , Redes e Vias Metabólicas , Metaboloma , Metabolômica/métodos , Obesidade/fisiopatologia , Fatores de Risco , Taiwan
18.
Insect Mol Biol ; 24(3): 338-47, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25702834

RESUMO

Artificial selection can provide insights into how insecticide resistance mechanisms evolve in populations. The underlying basis of such phenomena can involve complex interactions of multiple genes, and the resolution of this complexity first necessitates confirmation that specific genes are involved in resistance mechanisms. Here, we used a novel approach invoking a constrained RNA sequencing analysis to refine the discovery of specific genes involved in insecticide resistance. Specifically, for gene discovery, an additional constraint was added to the traditional comparisons of susceptible vs. resistant flies by the incorporation of a line in which insecticide susceptibility was 'recovered' within a resistant line by the removal of insecticide stress. In our analysis, the criterion for the classification of any gene as related to insecticide resistance was based on evidence for differential expression in the resistant line as compared with both the susceptible and recovered lines. The incorporation of this additional constraint reduced the number of differentially expressed genes putatively involved in resistance to 464, compared with more than 1000 that had been identified previously using this same species. In addition, our analysis identified several key genes involved in metabolic detoxification processes that showed up-regulated expression. Furthermore, the involvement of acetylcholinesterase, a known target for modification in insecticide resistance, was associated with three key nonsynonymous amino acid substitutions within our data. In conclusion, the incorporation of an additional constraint using a 'recovered' line for gene discovery provides a higher degree of confidence in genes identified to be involved in insecticide resistance phenomena.


Assuntos
Resistência a Inseticidas/genética , Inseticidas/farmacologia , Compostos Organotiofosforados/farmacologia , Tephritidae/efeitos dos fármacos , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Substituição de Aminoácidos , Animais , Ontologia Genética , Inativação Metabólica/genética , Inseticidas/metabolismo , Anotação de Sequência Molecular , Compostos Organotiofosforados/metabolismo , Análise de Sequência de RNA , Tephritidae/genética , Tephritidae/metabolismo , Transcriptoma
19.
J Appl Microbiol ; 118(1): 27-38, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25346320

RESUMO

AIMS: To investigate whether Photobacterium damselae subsp. piscicida (Phdp) can sense and directly respond to the presence of cationic antimicrobial peptides (AMPs). METHODS AND RESULTS: We performed proteomic methodologies to investigate the responsive proteins of Phdp on exposure to AMP Q6. Proteins significantly altered were analysed by two-dimensional gel electrophoresis (2-DE) and LC-ESI-Q-TOF MS/MS, thus resulting in five outer membrane proteins (OMPs), seven inner membrane proteins (IMPs) and 17 cytoplasmic proteins (CPs) identified. Quantitative real-time PCR was also applied to monitor the mRNA expression level of these target proteins. CONCLUSIONS: COG analysis revealed that upon exposure to AMP Q6, the majority of the upregulated proteins were involved in signal transduction mechanism, carbohydrate transport and metabolism, post-translational modification, protein turnover and chaperones, while the downregulated proteins were mainly related to energy production and conversion. Among them, phage-shock-protein A (PspA)-related stress response system was considered to play a crucial role. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first report elucidating Phdp AMP-response mechanism using proteomics approach. AMP-responsive proteins identified in this study could serve as attractive targets for developing more effective antimicrobial agents against Phdp and other marine bacterial pathogens.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Proteínas de Bactérias/metabolismo , Proteínas de Choque Térmico/metabolismo , Photobacterium/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Photobacterium/metabolismo , Photobacterium/ultraestrutura , Proteômica , Estresse Fisiológico
20.
Scand J Rheumatol ; 43(6): 498-502, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25178483

RESUMO

BACKGROUND: Gout is a common form of inflammatory arthritis that is triggered by the crystallization of monosodium urate (MSU). We investigated the potential proteins that relate to the pathogenesis or the spontaneous resolution of acute gouty arthritis. METHOD: We screened for differentially expressed proteins in the plasma of patients with acute gouty arthritis using two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) identification. We confirmed these findings in a population study of 209 subjects, and further determined the protein profile of the synovial fluid (SF) from 24 gouty patients during acute attack by liquid chromatography coupled with tandem MS (LC/MS/MS). RESULTS: The highly expressed apolipoprotein A-I (apoA-I) was identified in the plasma of acute gouty patients compared with healthy controls. Moreover, we detected high levels of SF apoA-I in 83.3% of acute gouty patients during attack. From the population study, apoA-I was increasingly associated with normouricaemia, hyperuricaemia, and acute gouty arthritis (ptrend < 0.001), and plasma uric acid (UA) and apoA-I were positively correlated (p = 0.0156). We used a human liver cell model and found that UA enhanced the hepatic apoA-I mRNA expression level (ptrend < 0.01) and apoA-I secretion level (ptrend = 0.002) in a dose-dependent manner. An elevated MSU concentration caused the endogenous apoA-I to deplete gradually. CONCLUSIONS: Based on the role of apoA-I in anti-inflammation, our observational data in acute gout support the hypothesis that apoA-I expression can be induced under the condition of a high concentration of UA and its elevated level may be implicated in the spontaneous resolution of acute gouty arthritis.


Assuntos
Apolipoproteína A-I/metabolismo , Artrite Gotosa/metabolismo , Ácido Úrico/metabolismo , Doença Aguda , Adulto , Idoso , Apolipoproteína A-I/análise , Apolipoproteína A-I/genética , Cristalização , Eletroforese em Gel Bidimensional , Humanos , Masculino , Pessoa de Meia-Idade , Líquido Sinovial/química , Ácido Úrico/sangue
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