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1.
Sci Rep ; 8(1): 11087, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30038363

RESUMO

Thulium iron garnet (TmIG) films with perpendicular magnetic anisotropy (PMA) were grown on gadolinium gallium garnet (GGG) (111) substrates by off-axis sputtering. High-resolution synchrotron radiation X-ray diffraction studies and spherical aberration-corrected scanning transmission electron microscope (Cs-corrected STEM) images showed the excellent crystallinity of the films and their sharp interface with GGG. Damping constant of TmIG thin film was determined to be 0.0133 by frequency-dependent ferromagnetic resonance (FMR) measurements. The saturation magnetization (Ms) and the coercive field (Hc) were obtained systematically as a function of the longitudinal distance (L) between the sputtering target and the substrate. A 170% enhancement of PMA field (H⊥) was achieved by tuning the film composition to increase the tensile strain. Moreover, current-induced magnetization switching on a Pt/TmIG structure was demonstrated with an ultra-low critical current density (jc) of 2.5 × 106 A/cm2, an order of magnitude smaller than the previously reported value. We were able to tune Ms, Hc and H⊥ to obtain an ultra-low jc of switching the magnetization, showing the great potential of sputtered TmIG films for spintronics.

2.
Zhonghua Wai Ke Za Zhi ; 56(2): 139-146, 2018 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-29397629

RESUMO

Objective: To compare the clinical outcome and health related quality of life(HRQoL)of patients with degenerative spinal deformity who underwent spino-pelvic fixation utilized second sacral alar-iliac(S(2)AI)with patient utilized traditional iliac screw(IS). Methods: Patients diagnosed as degenerative spinal deformity who underwent spino-pelvic fixation utilized either S(2)AI screw or Iliac screw at Department of Spine Surgery of Drum Tower hospital from January 2013 to January 2016 were retrospectively analyzed. Patients were divided into two groups according to the pelvic fixation technique. Cobb's angle, coronal balance distance(CBD), regional kyphosis(RK), sagittal vertical axis(SVA)were recorded at pre-operation, post-operation and last follow up. The MOS item short from the health survey(SF-36), visual analogue scale(VAS), Oswestry disability index(ODI) were also recorded at pre-operation and last follow up. Five physical examinations were administered to all patient at the last follow up to diagnose sacroiliac joint dysfunction, three tests resulting positive were regarded as dysfunction. Repeated measurement analysis of variance, t-test or non-parametric test was used to analyzed the data, respectively. Results: A total of 22 patients who met the inclusion were recruited in this study. Fourteen patients were utilized S(2)AI screw and 8 patients were utilized iliac screw.There were no significant differences in age, gender, follow up time between two groups. Cobb's angle, CBD, RK, SVA at pre- and post-operation and last follow up showed no significant difference between two groups.SF-36, ODI, VAS at pre-operation and last follow up showed no significant difference between two groups. Compared with baseline, Cobb's angle(44.4°±14.0° vs. 20.2°±7.2° vs. 18.3°±7.1°), C(7)PL-CSVL((25.3±16.0)mm vs. (10.3±5.7)mm vs. (9.2±4.2)mm), RK(33.0°(-12.0°, 50.0°) vs. 20.0°(-33.0°, 8.5°) vs. -19.0°(-29.0°, 19.0°)), SVA((31.5±34.4)mm vs. (12.1±8.4)mm vs. (10.9±7.2)mm), SF36-physical function summary(PCS)(39.8±14.3 vs. 68.2±21.5), SF36-mental component summary(MCS)(44.9±14.8 vs. 73.9±19.9), ODI(37.7±16.9 vs. 19.8±15.8), VAS(4.8±2.1 vs. 1.8±0.9) were significantly improved postoperatively in S(2)AI group(P<0.05). In the IS group, compared with baseline, Cobb's angle(54.3°±18.3° vs. 26.1°±13.2° vs. 25.6°±18.3°), C(7)PL-CSVL((31.0±16.0)mm vs. (13.9±7.0)mm vs. (12.4±6.6)mm), RK (47.0°(15.0°, 57.0°) vs. 4.0°(-10.0°, 16.0°) vs. 7.0°(-9.0°, 12.0°)), SVA((27.1±23.9)mm vs.(13.1±7.5)mm vs. (13.6±6.0)mm), SF36-PCS(29.7±7.1 vs. 61.1±11.2), SF36-MCS(35.9±7.1 vs. 64.0±11.1), ODI(48.6±13.4 vs. 19.0±10.7), VAS(4.9±1.8 vs. 2.6±1.3) were also significantly improved postoperatively(all P<0.05). There were two patients need revision surgery in the IS group due to the instrumentation-related complication. None of the patients in the S(2)AI group needed revision surgery. There were no instances of sacroiliac joint dysfunction in both groups at last follow up. Conclusion: Spino-pelvic fixation utilizing S(2)AI screw could provide similar correction rate to iliac screw and the sacroiliac joint penetration due to S(2)AI won't affect the HRQoL in patient with degenerative deformity who utilized S(2)AI.


Assuntos
Parafusos Ósseos , Cifose/cirurgia , Escoliose/cirurgia , Humanos , Ílio/cirurgia , Medição da Dor , Pelve , Período Pós-Operatório , Qualidade de Vida , Reoperação , Sacro/cirurgia , Escala Visual Analógica
3.
Nat Commun ; 9(1): 223, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29335558

RESUMO

Harnessing the spin-momentum locking of topological surface states in conjunction with magnetic materials is the first step to realize novel topological insulator-based devices. Here, we report strong interfacial coupling in Bi2Se3/yttrium iron garnet (YIG) bilayers manifested as large interfacial in-plane magnetic anisotropy (IMA) and enhancement of damping probed by ferromagnetic resonance. The interfacial IMA and damping enhancement reaches a maximum when the Bi2Se3 film approaches its two-dimensional limit, indicating that topological surface states play an important role in the magnetization dynamics of YIG. Temperature-dependent ferromagnetic resonance of Bi2Se3/YIG reveals signatures of the magnetic proximity effect of TC as high as 180 K, an emerging low-temperature perpendicular magnetic anisotropy competing the high-temperature IMA, and an increasing exchange effective field of YIG steadily increasing toward low temperature. Our study sheds light on the effects of topological insulators on magnetization dynamics, essential for the development of topological insulator-based spintronic devices.

4.
Clin Otolaryngol ; 43(1): 39-46, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28485064

RESUMO

OBJECTIVE: To investigate emergency room (ER) revisits and hospital readmissions following adenotonsillectomy (T&A) in children with sleep-disordered breathing (SDB), and correlations between SDB severity and ER revisits. DESIGN: Retrospective chart review study. SETTING: Tertiary referral centre. PARTICIPANT: 610 consecutive children underwent T&A for treating SDB. MAIN OUTCOME MEASURES: Sleep-disordered breathing severity was defined according to the apnoea-hypopnoea index (AHI) (primary snoring = AHI < 1; mild = AHI 1-5; moderate = AHI 5-10; and severe = AHI > 10). Revisit and readmission patterns within 30 days of the surgery were extracted and analysed. RESULTS: Of these children (mean age = 7.2 years; males = 72%), 49 (8.0%) had first ER revisit, nine (1.5%) had second ER revisits, and one (0.2%) had third ER revisits. Reasons for ER revisits were bleeding related (46%) or non-bleeding related (54%). The timing for revisits was 6.9±1.9 postoperative days for bleeding-related revisits and 9.3±10.0 days for non-bleeding-related revisits. Treatment strategies during these revisits were treat and release in 44 children (74.6%), admission for observation in eight children (13.5%), and admission for surgery in seven children (11.9%). The incidence of ER revisit and hospital readmission was similar among children with all levels of SDB severity. Multivariable logistic regression analysis showed that young children (<3 years) experienced an increased risk of non-bleeding-related revisits (odds ratio [OR] = 4.1). CONCLUSIONS: Children with severe SDB do not experience increased risks of revisit or readmission; however, young children are at increased risk of non-bleeding-related revisits.


Assuntos
Adenoidectomia/métodos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Síndromes da Apneia do Sono/cirurgia , Tonsilectomia/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Incidência , Lactente , Masculino , Readmissão do Paciente/tendências , Polissonografia , Complicações Pós-Operatórias/diagnóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Síndromes da Apneia do Sono/diagnóstico , Taiwan/epidemiologia
5.
Anaesth Intensive Care ; 43(4): 473-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26099759

RESUMO

Five popular scoring systems for postoperative nausea and vomiting (PONV) were validated and compared with two new predictive models in a Taiwanese population. Nine hundred and ninety-two patients receiving general anaesthesia in a tertiary hospital were investigated in a prospective observational cohort study. Patient demographic data and the incidence of nausea or vomiting in the first 24 hours after surgery were recorded. The overall incidence of PONV was 42%. The area under the curve (AUC) of the five published PONV risk scoring systems was 0.62 to 0.67. Logistic regression analysis in this study cohort showed that female sex and a history of PONV/car sickness were the only statistically significant independent risk factors for PONV (likelihood ratio test P <0.001).The AUCs of our two-predictor and gender-only models were 0.668 and 0.643, respectively (Nagelkerke R² = 0.122 and 0.109). Goodness-of-fit showed that a two-predictor model predicted outcome that was in agreement with the observed outcome (P=0.973). Both the two-predictor model and the Apfel score had a similar AUC that was significantly different from the AUCs of the other models. The AUC for the gender-only model in our population was similar to that of the simplified Koivuranta and the Palazzo and Evans scores (AUC=0.659 and 0.632; P=0.137 and 0.513 respectively). All AUCs had only moderate discrimination power but our female gender-only model was much simpler. Using female gender as the only predictor of PONV had predictive power with 75% sensitivity and 54% specificity.


Assuntos
Anestesia Geral/efeitos adversos , Náusea e Vômito Pós-Operatórios/induzido quimicamente , Área Sob a Curva , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade , Fatores Sexuais , Taiwan
8.
Oral Microbiol Immunol ; 23(3): 220-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18402608

RESUMO

BACKGROUND/AIMS: In the present study, we attempted to develop a simulated model to explore the causal effects of periodontal pathogens on skeletal homeostasis in postmenopausal osteoporosis. METHODS: Fifty-three female adult ICR mice were randomly assigned to an experimental group (ovariectomized) or a control group. A single injection of Porphyromonas gingivalis lipopolysaccharide (P. gingivalis-LPS, ATCC 33277) or Escherichia coli lipopolysaccharide (E. coli-LPS) was administered intraperitoneally 4 weeks after an ovariectomy. Concentrations of interleukin-6 (IL-6), osteoprotegerin (OPG), and the receptor activator of nuclear factor-kappaB ligand (RANKL) in serum were subsequently analyzed using an enzyme-linked immunosorbent assay (ELISA). RESULTS: Under stimulation with P. gingivalis-LPS or E. coli-LPS, the concentration of OPG rose in both groups. The serum level of RANKL showed a decreasing trend 24 h after the injection in both groups. After injection of P. gingivalis-LPS in both the experimental and control animals, the OPG : RANKL ratio increased 24 h after the booster (22.26-620.99, P < 0.05). The serum level of IL-6 in the experimental group significantly increased 1-6 h after administration of E. coli-LPS and 1-3 h after administration of P. gingivalis-LPS (P < 0.05). CONCLUSIONS: A single booster injection of P. gingivalis-LPS induced short-term changes in OPG, RANKL, and IL-6 serum levels in this ovariectomized mouse model.


Assuntos
Interleucina-6/sangue , Lipopolissacarídeos/farmacologia , Osteoprotegerina/sangue , Ovariectomia , Porphyromonas gingivalis , Ligante RANK/sangue , Animais , Modelos Animais de Doenças , Escherichia coli , Feminino , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Injeções Intraperitoneais , Lipopolissacarídeos/administração & dosagem , Camundongos , Camundongos Endogâmicos ICR , Osteoporose/fisiopatologia , Osteoprotegerina/efeitos dos fármacos , Ligante RANK/efeitos dos fármacos , Distribuição Aleatória , Fatores de Tempo
9.
Br J Cancer ; 98(1): 9-14, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18182974

RESUMO

Most of the early studies published on soy and breast cancer were not designed to test the effect of soy; the assessment of soy intake was usually crude and few potential confounders were considered in the analysis. In this review, we focused on studies with relatively complete assessment of dietary soy exposure in the targeted populations and appropriate consideration for potential confounders in the statistical analysis of study data. Meta-analysis of the 8 (1 cohort, 7 case-control) studies conducted in high-soy-consuming Asians show a significant trend of decreasing risk with increasing soy food intake. Compared to the lowest level of soy food intake (or=20 mg isoflavones per day). In contrast, soy intake was unrelated to breast cancer risk in studies conducted in the 11 low-soy-consuming Western populations whose average highest and lowest soy isoflavone intake levels were around 0.8 and 0.15 mg per day, respectively. Thus, the evidence to date, based largely on case-control studies, suggest that soy food intake in the amount consumed in Asian populations may have protective effects against breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Alimentos de Soja , Dieta , Humanos , Fatores de Risco
11.
Kidney Int ; 71(8): 764-70, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17290293

RESUMO

Most human pyelonephritogenic Escherichia coli express the PapG II adhesin. However, the role of the PapG II adhesin in enhancing the establishment and persistence of E. coli infection in the kidney is controversial. A pyelonephritogenic strain, EC114, which possesses one copy of the papG II gene, but without other virulence factors (such as S/F1C-fimbriae, hemolysin, and cytotoxic necrotizing factor 1) was selected for the construction of a papG II mutant. The resulting papG II mutant was confirmed by polymerase chain reaction, Southern hybridization, and agglutination assay, and designated as MEC114. We compared MEC114 with the parental strain (EC114) for colonization ability in the bladder and kidney of female BALB/c mice, which were challenged transurethrally with 50 microl of a low (5x10(4) CFU (colony-forming unit)) or high (5x10(8) CFU) dose of EC114 or MEC114 and assessed 1, 3, and 7 days after inoculation. Geometric means of quantitative bacterial counts in the kidney were significantly decreased when challenged with MEC114 on day 3 after inoculation, at both low and high dose (P<0.05), as compared with EC114. On the seventh day, both strains were mainly cleared from the kidney. Renal biopsy showed a similar degree of inflammatory response to both strains 1, 3, and 7 days after inoculation. In brief, the PapG II adhesin can enhance the early establishment of E. coli infection in the kidney, but the bacteria do not maintain infection owing to the host immune response.


Assuntos
Adesinas de Escherichia coli/fisiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli/patogenicidade , Fímbrias Bacterianas/fisiologia , Pielonefrite/microbiologia , Adesinas de Escherichia coli/genética , Animais , Feminino , Rim/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Fenótipo , Pielonefrite/patologia , Infecções Urinárias/microbiologia , Virulência/fisiologia
12.
Int J Gynecol Cancer ; 16(4): 1574-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16884368

RESUMO

The purpose of the study was to evaluate the specimen adequacy and diagnostic accuracy of loop conization in microinvasive carcinoma of the cervix. A retrospective study was conducted from 1997 to 2003 at the Colposcopic Clinic, Department of Gynecology and Obstetrics, Chang Gung Memorial Hospital, Taipei, Taiwan. Sixty-three consecutive patients with microinvasive carcinoma of the cervix receiving cold-knife conization (35 patients) or loop conization (28 patients) were included in the study. All patients underwent definitive hysterectomy. We reviewed the conization specimen together with the hysterectomied uterus to compare the two conization techniques with respect to the histopathologic interpretation and diagnostic accuracy. The mean depth of cone specimens was significantly less in the loop conization compared with cold-knife conization (1.65 versus 2.35 cm, P = 0.035). Regarding the application of conization, the loop conization was completed in a single slice in 27 patients (77.1%) and in multiple slices in 8 patients (22.9 %), in spite of encouragement to perform conization in a one-pass application when possible. However, the cold-knife specimens were invariably a single cone-shaped piece. As reviewed by microscopic examination, the rate of tissue transection was significantly higher in the loop group than in the cold-knife group (14.3% versus 0%, P = 0.04). Because of tissue transection and disorientation, pathologic evaluation of stromal status was inadequate in 11.4% (4/35) of the loop cones as opposed to none of the 28 cold-knife cones. After assessing the hysterectomy specimens, the clinical diagnoses in the loop group were downgraded in three patients compared with only one in the cold-knife group. Data from this investigation suggest that cervical cold-knife conization is superior to loop conization as a method to assess microinvasive cervical cancer.


Assuntos
Conização , Displasia do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/cirurgia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Histerectomia , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologia
13.
Phytomedicine ; 13(5): 366-70, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16635745

RESUMO

The water extract of Anoectochilus formosanus Hayata showed a potent tumor inhibitory activity in BALB/c mice after subcutaneous transplantation of CT-26 murine colon cancer cells. The tumor-inhibition ratios of mice pre-administered with A. formosanus for 2 days before tumor transplantation, and treated further for 12 consecutive days, were 55.4% and 58.9% at the oral dose of 50 and 10 mg/mouse per day, respectively. Even for the tumor-bearing mice, after oral administration of the water extract of A. formosanus for 12 consecutive days, the tumor inhibition ratios were still 23.8% and 40.5% at doses of 50 and 10 mg/mouse, respectively. Because the low-concentration water extract of A. formosanus does not show direct cytotoxicity in CT-26 tumor cells, we observed further that oral administration of the water extract of A. formosanus may activate murine immune responses, such as stimulating the proliferation of lymphoid tissues and activating the phagocytosis of peritoneal macrophages against Staphylococcus aureus. This study suggests that the antitumor activity of A. formosanus may be associated with its potent immunostimulating effect. It is worth further analyzing the immunomodulating component purified from A. formosanus, and evaluating its potential value for the treatment of human cancers.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Linfócitos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Orchidaceae/química , Animais , Linhagem Celular Tumoral/efeitos dos fármacos , Feminino , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Fagocitose/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/imunologia , Testes de Toxicidade/métodos
14.
J Urol ; 166(5): 1643-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11586193

RESUMO

PURPOSE: We compared the genotypes of fimbriae or adhesions of Escherichia coli causing acute pyelonephritis in adults with and without urinary tract abnormalities. MATERIALS AND METHODS: We studied a total of 92 E. coli strains isolated from 54 patients with acute pyelonephritis and a normal urinary tract, and 38 with urinary tract abnormalities. Of those with urinary tract abnormalities 13 with moderate to severe hydronephrosis were also considered a separate group for the purpose of analysis. The genes of 7 known fimbriae or adhesins of E. coli were detected by the polymerase chain reaction, including the papG class I to III alleles (PapG adhesins of P-fimbriae), sfa/foc (S-/F1C-fimbriae), fimH (type 1 fimbriae), and afa (afimbrial adhesin). Virulence genes associated with APN were identified by comparing the prevalence of each of these 7 genes in E. coli strains from 54 patients with acute pyelonephritis with a normal urinary tract to the prevalence in the strains from 37 patients with acute cystitis using univariate and multivariate analysis. Differences in the prevalence of the genes associated with acute pyelonephritis and the incidence of underlying illness were then compared in the 3 acute pyelonephritis groups. RESULTS: On univariate and multivariate analysis the papG class II allele was the only virulence gene associated with acute pyelonephritis (p <0.0001 and 0.001, respectively). No significant difference was noted in the prevalence of underlying medical disease in the 3 acute pyelonephritis groups. The papG class II allele was significantly less predominant in E. coli strains isolated from acute pyelonephritis cases with versus without urinary tract abnormalities (76% versus 93%, p = 0.03). The incidence of the papG class II allele in patients with urinary tract abnormalities and moderate to severe hydronephrosis was less than in those without urinary tract abnormalities (69% versus 93%, p = 0.04). CONCLUSIONS: Our results imply that the papG class II allele has an important role in E. coli infection in patients with acute pyelonephritis and a normal urinary tract, while urinary tract abnormalities and/or obstruction may permit ascending infection of E. coli strains with lower adhesive ability.


Assuntos
Adesinas de Escherichia coli/fisiologia , Infecções por Escherichia coli/fisiopatologia , Proteínas de Fímbrias , Fímbrias Bacterianas/fisiologia , Pielonefrite/fisiopatologia , Sistema Urinário/anormalidades , Doença Aguda , Alelos , Escherichia coli/patogenicidade , Humanos , Virulência
15.
Biochem Biophys Res Commun ; 285(1): 129-35, 2001 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-11437382

RESUMO

Megakaryocyte differentiation is often accompanied by the changes of gene expression pattern. Here we reported that the expression of DAB2, a putative adaptor protein in cell signaling, was induced at the protein and mRNA levels upon 12-O-tetradecanoylphorbol-13-acetate-mediated megakaryocyte differentiation of human chronic myeloid leukemic K562 cells. On the other hand, the differentiation agents DMSO and retinoic acid had no effect on DAB2 expression. Analysis of promoter activity with the human DAB2 luciferase reporter constructs suggested that the regulation is partially at the transcriptional level. The responsive sequences located within an 80-bp DAB2 promoter region. To determine the involvement of MEK1-p42/p44 MAPK pathway in mediating DAB2 gene expression, we have performed the following experiments and found that (i) there was sustained activation of p42/p44 MAPK, but not p38 MAPK, upon K562 cells differentiation; (ii) application of MEK1 inhibitor U0126 reduced the expression of DAB2 protein, mRNA and promoter activity, as well as cell differentiation; (iii) constitutively active MEK1 increased DAB2 promoter activity; and (iv) dominant negative ERK2 abolished constitutively active MEK1-induced DAB2 promoter activity. Taken together, our results indicate that DAB2 gene is induced upon megakaryocyte differentiation by the MEK1-p42/p44 MAPK pathway and may define a new role of DAB2 in hematopoietic cell differentiation.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Diferenciação Celular/genética , Regulação da Expressão Gênica , Megacariócitos/citologia , Proteínas/genética , Proteínas Adaptadoras de Transdução de Sinal , Proteínas Reguladoras de Apoptose , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , DNA , Genes Supressores de Tumor , Humanos , Células K562 , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Acetato de Tetradecanoilforbol/farmacologia , Proteínas Supressoras de Tumor
16.
Lancet ; 357(9269): 1673-4, 2001 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-11425375

RESUMO

Vitamin D affects calcium metabolism and prevents proliferation of colon cells in vitro. In human beings the main circulating form of vitamin D is 25-hydroxyvitamin D; to regulate calcium homoeostasis, this form must be converted to 1alpha, 25-dihydroxyvitamin D by 1alpha-hydroxylation in the kidney with 25-hydroxyvitamin D-1alpha-hydroxylase. Cultured transformed colon cancer cells can convert 25-hydroxyvitamin D(3) to 1alpha,25-dihydroxyvitamin D(3). We identified messenger RNA (mRNA) for 25-hydroxyvitamin D-1alpha-hydroxylase in normal colon tissue and in malignant and adjacent normal colon tissue. These findings support the notion that vitamin D might have a role in cell growth regulation and cancer protection, and might be the explanation for why the risk of dying from colorectal cancer is highest in areas with the least amount of sunlight.


Assuntos
25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Neoplasias Colorretais/enzimologia , RNA Mensageiro/genética , Cálcio/metabolismo , Causas de Morte , Divisão Celular/genética , Transformação Celular Neoplásica/patologia , Colo/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Humanos , Reação em Cadeia da Polimerase , Valores de Referência , Luz Solar , Análise de Sobrevida , Vitamina D/fisiologia
17.
Biochem Biophys Res Commun ; 283(1): 205-8, 2001 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-11322789

RESUMO

Cancer cells differ from normal cells in many aspects, including loss of differentiation and uninhibited cell proliferation. Recent studies have suggested that gut-enriched Krüppel-like factor (GKLF) played an important role in the regulation of cell growth in the colon. Studies from this laboratory have shown that GKLF protein predominantly expressed in the cytoplasm but not the nucleus of colon cancer cells, suggesting that impaired nuclear translocation of GKLF might contribute to cancer formation. In this report, a region containing putative nuclear localization signal (NLS) of GKLF (PKRGRR; amino acids 385-390) was investigated. Mutation of KR to WT had no effect on the inhibitory properties of GKLF on cyclin D1 promoter activity and [(3)H]thymidine uptake in HT-29 cells, whereas mutation of RR to GL abolished GKLF function completely. Additional mutation analyses demonstrated that Arg(390) is the most critical moiety within this region that mediated GKLF function and its nucleus localization. Cotransfection of Arg(390) mutant (RR/RS) completely inhibited wild-type GKLF function, and GFP-RR/RS GKLF fusion proteins failed to translocate to the nucleus. The results from this study demonstrate that Arg(390) confers the NLS of GKLF and that the nucleus-localization-deficient mutant serves as dominant-negative inhibitor of GKLF function.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Genes Dominantes/fisiologia , Sinais de Localização Nuclear/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Substituição de Aminoácidos/genética , Linhagem Celular , Ciclina D1/genética , DNA/biossíntese , Proteínas de Ligação a DNA/farmacologia , Genes Reporter , Proteínas de Fluorescência Verde , Células HT29 , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like , Proteínas Luminescentes/genética , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Relação Estrutura-Atividade , Timidina/metabolismo , Timidina/farmacocinética , Fatores de Transcrição/farmacologia , Transfecção
18.
Am J Nephrol ; 21(1): 28-34, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11275629

RESUMO

There are some racial differences in the prevalence and prognosis of idiopathic nephrotic syndrome; however, reports about minimal change disease (MCD) in Chinese were rare. We retrospectively analyzed 123 Chinese adults with idiopathic nephrotic syndrome, who received percutaneous renal biopsy in our institution within the last 10 years. In total, 46 patients (37.4%) were compatible with the pathological diagnosis of MCD. The male to female ratio was 1.2:1. The mean age of onset was 30.9 years, and 80% of the patients with MCD were less than 40 years. The mean daily proteinuria was 10.2 g, and serum albumin was 1.8 mg/dl. Azotemia occurred in 16 (35%) of 46 cases; hypertension, 13%; and microscopic hematuria, 13%. High selectivity index for proteinuria (SI <0.1) was noted in 12 (39%) of 31 cases; and high IgE level was found in 83.7% of the study subjects, although only one case had allergic history. Complete remission in 36 MCD patients treated with corticosteroid was achieved by 42% (15/36), 80% (29/36), and 94% (34/36) within 4, 8, and 12 weeks, respectively. The time interval to remission was similar between the younger group (<40 years old, 1.7 months) and older group (>40 years old, 1.6 months). Nineteen (56%) of 34 cases with steroid response did not relapse, and the other cases (44%) had a mean relapse rate of 1.5 times per patient within a period of 45 months. The age of onset in MCD cases was not significantly correlated with steroid-responsive rate, and the time interval to remission. However, a tendency existed between the onset in the young age and the sequentially relapsing rate (p = 0.06). Two cases with primary steroid resistance and 5 cases with frequent relapse or steroid dependence responded well to intravenous pulse therapy of cyclophosphamide, except one refractory case. No thrombotic episode was ever noted in our group. Regarding infectious complications, primary peritonitis occurred in one, pneumonia in one, and cellulitis in 6 cases during active nephrotic stage. Two mortality cases, one with E. coli-related necrotizing fasciitis and one from pneumonia, were noted. In brief, compared with children, adult patients with MCD had lesser high selectivity index for proteinuria, the same steroid-responsive rate (94%), but slower response, and significantly lesser relapsing rate. The intravenous pulse therapy of cyclophosphamide may be an alternative regimen for adult patients with steroid resistance or dependency. In addition, the Asian adult-onset MCD had younger age, male predominance, and lesser relapsing rate in comparison to those of the Western population.


Assuntos
Nefrose Lipoide/genética , Adolescente , Adulto , Fatores Etários , Idade de Início , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taiwan
19.
Proc Natl Acad Sci U S A ; 98(1): 99-104, 2001 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-11134531

RESUMO

The 207-kDa polyketide synthase (PKS) module (residues 1-1895) and the 143-kDa nonribosomal peptidyl synthetase (NRPS) module (1896-3163) of the 350-kDa HMWP1 subunit of yersiniabactin synthetase have been expressed in and purified from Escherichia coli in soluble forms to characterize the acyl carrier protein (ACP) domain of the PKS module and the homologous peptidyl carrier protein (PCP(3)) domain of the NRPS module. The apo-ACP and PCP domains could be selectively posttranslationally primed by the E. coli ACPS and EntD phosphopantetheinyl transferases (PPTases), respectively, whereas the Bacillus subtilis PPTase Sfp primed both carrier protein domains in vitro or during in vivo coexpression. The holo-NRPS module but not the holo-PKS module was then selectively aminoacylated with cysteine by the adenylation domain embedded in the HMWP2 subunit of yersiniabactin synthetase, acting in trans. When the acyltransferase (AT) domain of HMWP1 was analyzed for its ability to malonylate the holo carrier protein domains, in cis acylation was first detected. Then, in trans malonylation of the excised holo-ACP or holo-PCP(3)-TE fragments by HMWP1 showed both were malonylated with a 3:1 catalytic efficiency ratio, showing a promiscuity to the AT domain.


Assuntos
Proteína de Transporte de Acila/metabolismo , Complexos Multienzimáticos/metabolismo , Panteteína/análogos & derivados , Peptídeo Sintases/metabolismo , Fenóis , Processamento de Proteína Pós-Traducional , Sideróforos/metabolismo , Tiazóis , Yersinia pestis/enzimologia , Proteína de Transporte de Acila/química , Proteína de Transporte de Acila/genética , Proteína de Transporte de Acila/isolamento & purificação , Acilação , Aciltransferases/genética , Aciltransferases/metabolismo , Apoproteínas/química , Apoproteínas/metabolismo , Bacillus subtilis/enzimologia , Proteínas da Membrana Bacteriana Externa , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Cisteína/metabolismo , Escherichia coli , Holoenzimas/química , Holoenzimas/metabolismo , Proteínas de Ligação ao Ferro , Cinética , Malonil Coenzima A/metabolismo , Estrutura Molecular , Peso Molecular , Complexos Multienzimáticos/química , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/isolamento & purificação , Panteteína/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/metabolismo , Peptídeo Sintases/química , Peptídeo Sintases/genética , Peptídeo Sintases/isolamento & purificação , Proteínas Periplásmicas de Ligação , Estrutura Terciária de Proteína , Subunidades Proteicas , Proteínas Recombinantes
20.
Genes Chromosomes Cancer ; 30(1): 80-6, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11107179

RESUMO

To characterize phenotypic and genotypic changes in gastric cancer (GC), DNA copy number aberrations (CNAs) were assessed in 53 tumors using comparative genomic hybridization (CGH) and correlated with clinicopathologic characteristics and status of TP53 and replication error (RER). The number of CNAs per tumor was 6.8 (gain 5.3, loss 1.5), and the number of changes was significantly higher in tumors with advanced stage, TP53 mutation, and without RER than in those with early stage (7.7 vs. 3.0), no TP53 mutations (12.4 vs. 4.8) or RER phenotype (8.2 vs. 2.6). Frequent abnormalities included gains on chromosomal arms 8q (43%), 6q (26%), 11q (26%), 13q (24%), 7p (23%), 17q (23%), and 20q (23%), and losses on chromosomal arms 16q (26%), 19p (23%), 5q (19%), 3p (15%), 4q(15%), and 1p (15%). Advanced GC demonstrated a higher prevalence of gains of 8q (51% vs. 10%, P < 0.05) and loss of 16q (33% vs. 0%, P < 0.05) than early GC. Gains on 8q (64% vs. 20%, P < 0.05), 17q (39% vs. 4%, P < 0.05) and losses on 3p (25% vs. 4%, P = 0.05) and 5q (32% vs. 4%, P < 0.05) were higher in intestinal GC than in diffuse GC. On the other hand, gains on 13q were more common in the diffuse type (40% vs. 11%, P < 0.05). As compared with noncardia cancer, cardia cancer showed more gains on 7p (58% vs. 12%, P < 0.05) and 20q (58% vs. 12%, P < 0.05) and more losses on 4q (50% vs. 5%, P < 0.05). The finding of histology-related aberrations and the combination of CGH and molecular data thus provide additional evidence suggesting genetic heterogeneity of GC.


Assuntos
Replicação do DNA/genética , Hibridização de Ácido Nucleico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Aberrações Cromossômicas/genética , Progressão da Doença , Feminino , Dosagem de Genes , Genes p53/genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Deleção de Sequência/genética , Neoplasias Gástricas/epidemiologia
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