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1.
Materials (Basel) ; 16(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36676242

RESUMO

Determining an optimal combination of laser process parameters can significantly improve the efficiency and quality of 40Cr13 steel surface processing. In this study, two machine learning models (ELMSS and ELMPS) were proposed to predict the processing results of surface features to optimize process parameters. The prediction accuracies of the proposed models were always higher than those of traditional back propagation (BP) and radial basis function (RBF) neural networks, and the calculation time of the proposed models was significantly reduced. In comparison, the prediction accuracy ranking for ablation depth was ELMSS (92.6%), BP (89.8%), and RBF (89.6%), and for the ablation width, it was ELMSS (98.3%), BP (97.4%), and RBF (96.1%). The material removal rate was 92.4%, 91.1%, and 89.1% for ELMSS, BP, and RBF, respectively. Finally, the prediction accuracy ranking for surface roughness was 86.8%, 80.7%, and 79.5% for ELMPS, BP, and RBF, respectively. After optimization by the genetic algorithm, the prediction accuracies of the proposed models for the depth, width, material removal rate, and surface roughness reached 94.0%, 99.0%, 93.2%, and 91.2%, respectively. With the support of ELMSS and ELMPS, the results of the surface features can be predicted before machining and the appropriate process parameters can be selected in advance.

2.
Calcif Tissue Int ; 104(6): 622-630, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30737534

RESUMO

This case-control study aimed to examine the effect of high serum parathyroid hormone (PTH) level, especially the effect of secondary hyperparathyroidism (SHPT) related to hypovitaminosis D, on bone metabolism and bone phenotypes. We included a total of 830 Chinese postmenopausal women aged ≥ 50 years with serum 25-hydroxyvitamin D (25(OH)D) level < 30 ng/ml, among whom 415 women had prevalent vertebral fractures (VFs) and others were age-matched controls. We measured serum levels of 25(OH)D, PTH and bone turnover markers (BTMs), which included C-terminal telopeptide of type I collagen (ß-CTX), N-aminoterminal prepeptide of type I procollagen (P1NP) and osteocalcin (OC). Bone mineral densities (BMDs) at lumbar spine and femoral neck were quantified by dual-energy X-ray absorptiometry. Morphometric VFs were validated by lateral radiograph of thoracolumbar spine. Compared to fracture-free controls, women with VFs exhibited a higher serum level of PTH and a higher percentage of SHPT (both p < 0.05), but had a similar serum level of 25(OH)D (p = 0.166). Positive correlations were depicted between PTH and BTMs (all p < 0.01), and between 25(OH)D and bone formation markers (p = 0.013 for OC, p = 0.068 for P1NP), whereas no significant correlation was identified between both calciotropic hormones and BMDs or between 25(OH)D and ß-CTX (all p > 0.05). Increasing PTH was associated with an increased risk of VFs independent of 25(OH)D and BMD [odds ratio (OR) per SD increase in PTH 1.016, 95% confidence interval (95% CI) 1.006-1.027]. Moreover, women with SHPT (i.e., > 68 pg/ml) had about three times odds for VF compared to women with normal PTH levels (OR 3.270, 95% CI 1.581-6.760). These data suggest that evaluated serum PTH level might promote the bone remodeling and then lead to increased risks of VFs among Chinese postmenopausal women with vitamin D insufficiency.


Assuntos
Biomarcadores/sangue , Remodelação Óssea/fisiologia , Hormônio Paratireóideo/sangue , Fraturas da Coluna Vertebral/sangue , Fraturas da Coluna Vertebral/epidemiologia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Estudos de Casos e Controles , China/epidemiologia , Colágeno Tipo I/sangue , Feminino , Colo do Fêmur , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/epidemiologia , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pós-Menopausa , Prevalência , Pró-Colágeno/sangue , Fraturas da Coluna Vertebral/complicações , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/complicações
3.
Biochem Biophys Res Commun ; 484(1): 144-151, 2017 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-28093232

RESUMO

This study aimed to investigate the role of phospholipase Cε (PLCε) in the skin wound healing process. PLCε, an effect factor of Ras/Rap small G protein, plays a crucial role in skin inflammation by regulating inflammatory cytokines. Inflammatory responses are closely associated with wound healing. Full-thickness skin wounds were made in the PLCε knockout (KO) and wild-type (WT) mice, and the healing process was analyzed. The macroscopic wound closure rate declined in the PLCε KO mice on days 3, 4, and 5 after wounding, following the decreased expression of interleukin (IL)-6, chemokine (C-X-C motif) ligand (Cxcl)-1, Cxcl-2, and chemokine (C-C motif) ligand (Ccl) 20. The proliferation rate of epidermal keratinocytes was not affected by PLCε, but silencing of PLCε resulted in the delayed migration of keratinocytes. Moreover, the scars were found to be much smaller in the PLCε KO mice than in the WT mice. The mRNA expression of Ccl20, collagen (Col) 6a1, and Col17a1 decreased in the PLCε KO mice. These results were in agreement with a previous hypothesis that PLCε might delay the early stage of cutaneous wound healing by inhibiting the migration of keratinocytes, and decrease the expression of Col6a1, Col17a1, and Ccl20 by inhibiting the inflammatory response to reduce scar formation. This study shed light on a novel role of PLCε in wound healing and provided new therapeutic approaches to target PLCε for diminishing scar formation after injury.


Assuntos
Cicatriz/prevenção & controle , Fosfoinositídeo Fosfolipase C/genética , Cicatrização/genética , Animais , Células Cultivadas , Cicatriz/genética , Colágeno/biossíntese , Citocinas/biossíntese , Inativação Gênica , Humanos , Mediadores da Inflamação/metabolismo , Queratinócitos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Interferente Pequeno/genética
4.
Mol Med Rep ; 12(4): 6152-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26239674

RESUMO

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disease characterized by combined occurrence of tumors and hyperplasia in tissues including the parathyroid, gastrointestinal endocrine tissue and anterior pituitary. Heterozygous germline mutation of the tumor suppressor gene MEN1 is the cause of the disease. Treatment and long­term follow up of patients with MEN1 are rarely reported in the literature due to the relative rarity of the disease; thus, there is limited understanding of tumor biology and behavior, and heterogeneous clinical presentation. This case report observed a family that presented with MEN1 c.825­1G>A mutation. The clinical features and treatment were followed up for >20 years. Detailed family history of this pedigree was investigated and followed up. Genomic DNA was extracted by standard methods from peripheral leukocytes. The coding sequence, including 9 coding exons and 16 splice junctions of the MEN1 gene of leukocyte DNA was determined. The proband presented with gastrinoma, pituitary tumors, hyperparathyroidism, thymoma and lung carcinoid tumors, and was followed from age 35 to 54 years old. During the 20 years, the patient underwent four surgeries: Trans­sphenoidal adenomectomy, followed by post operative radiotherapy at 39 years; hyperplasia parathyroid gland resection at 40 years; removal of pancreatic, head and neck, duodenal, gallbladder, bile duct, subtotal gastric (4/5) and pyloric region lymph nodes at age 41; and a thymectomy and left lung carcinoid tumor removal procedure at the age of 49. The patient died of unrelated trauma and had a relatively stable illness course. DNA sequence analysis revealed MEN1 gene c.825­1G>A or IVS 5­1G>A mutation in the family. Two carriers in the pedigree were identified and followed up. Data indicated that although MEN1 is a complex disease involving multiple organs and systems, MEN1 tumors should be considered surgically curable. If patients are properly cared for by multidisciplinary teams comprising of relevant specialists with experience in the diagnosis and treatment of patients with endocrine tumors, patients may have a relatively positive prognosis.


Assuntos
Mutação em Linhagem Germinativa , Neoplasia Endócrina Múltipla Tipo 1/genética , Proteínas Proto-Oncogênicas/genética , Adulto , Povo Asiático/genética , Éxons , Evolução Fatal , Feminino , Heterozigoto , Humanos , Íntrons , Masculino , Pessoa de Meia-Idade , Linhagem , Prognóstico , Análise de Sequência de DNA
5.
Hormones (Athens) ; 13(3): 345-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25079458

RESUMO

OBJECTIVE: To determine if GC (group-specific component globulin) and CYP2R1 genetic variants have an association with serum 25-OHD3 levels, BMD or bone turnover markers in a population of Chinese postmenopausal women. DESIGN: We randomly selected 1494 postmenopausal women of the Han ethnic group from seven communities in Beijing. BMD was determined by dual energy X-ray absorptiometry; serum bone turnover markers and 25-OHD3 were measured by the automated Roche electrochemiluminescence system; genotypes of GC and CYP2R1 were detected by the TaqMan allelic discrimination assay. Multiple statistic methods were used to test the associations of SNP genotypes and vitamin D levels. RESULTS: In our sample, 89.6% women had vitamin D deficiency and another 9.8% had vitamin D insufficiency. The variants of rs2298849 (ß=0.105, P<0.001) in GC were significantly associated with serum 25-OHD3 levels. Allele G of rs2298849 might be protective for serum 25-OHD3 level. Among the haplotypes of rs222020-rs2298849, CG (ß=0.104, P=0.001) corresponded to increasing serum 25-OHD3 concentrations. CYP2R1 polymorphisms showed some significant association with serum ß-CTX and P1NP levels. CONCLUSIONS: We found that GC variants had a significant association with serum 25-OHD3 levels among postmenopausal women of the Han ethnic group in Beijing, while CYP2R1 variants were not found to be significant.


Assuntos
Calcifediol/sangue , Colestanotriol 26-Mono-Oxigenase/genética , Polimorfismo de Nucleotídeo Único , Pós-Menopausa/sangue , Pós-Menopausa/genética , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/genética , Proteína de Ligação a Vitamina D/genética , Absorciometria de Fóton , Idoso , Povo Asiático/genética , Biomarcadores/sangue , Densidade Óssea/genética , China , Colágeno Tipo I/sangue , Família 2 do Citocromo P450 , Feminino , Frequência do Gene , Estudos de Associação Genética , Haplótipos , Humanos , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Fenótipo , Pós-Menopausa/etnologia , Valor Preditivo dos Testes , Pró-Colágeno/sangue , Fatores de Risco , Estações do Ano , Fatores de Tempo , Deficiência de Vitamina D/diagnóstico , Deficiência de Vitamina D/etnologia
6.
Menopause ; 21(5): 515-21, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24045674

RESUMO

OBJECTIVE: GALNT3 gene encodes the glycosyltransferase polypeptide N-acetylgalactosaminyltransferase-3 (ppGalNacT3), which initiates the O-glycosylation of fibroblast growth factor 23 (FGF23) that is important in phosphorous regulation. Inactivating mutations of the GALNT3 gene can cause familial tumoral calcinosis. The aim of present study is to investigate the association of GALNT3 polymorphisms with osteoporosis phenotypes in Chinese postmenopausal women. METHODS: A community-based population of 1,353 postmenopausal women was randomly selected in Beijing. Bone mineral densities (BMDs) of the lumbar spine, femoral neck (FN), and total hip (TH) were measured by dual-energy x-ray absorptiometry. Vertebral fracture phenotypes were ascertained by vertebral x-ray reading. Osteoporotic fracture phenotypes were obtained from questionnaires. Single nucleotide polymorphisms of GALNT3 were determined by TaqMan allelic discrimination assay. Differences in BMD, serum phosphorus, or serum calcium across diverse genotypes or haplotypes were analyzed by general linear model analysis of covariance. Linear regression or logistic regression was used for association analyses of different osteoporosis phenotypes, phosphorous, or calcium. Partial correlation was used to investigate the relationship between phosphorus or calcium and BMD. RESULTS: We found that polymorphisms of rs1863196, rs6710518, and rs13429321 were significantly associated with FN BMD (P values of 0.002, 0.003, and 0.002, respectively). Polymorphisms of rs1863196, rs6710518, rs4667492, rs13429321, and rs6721582 were associated with TH BMD (P values of 0.002, 0.004, 0.037, 0.005, and 0.014, respectively). Haplotype-1 additive and dominant models were found to be associated with TH BMD (P values of 0.035 and 0.024, respectively). Haplotype-2 dominant model was found to be associated with FN BMD (P = 0.003) and TH BMD (P = 0.001). CONCLUSIONS: GALNT3 may play a role in genetic susceptibility to osteoporosis among Chinese postmenopausal women. Efforts should be exerted to replicate our findings in other similar and ethnically diverse populations.


Assuntos
Predisposição Genética para Doença/epidemiologia , Vértebras Lombares/lesões , N-Acetilgalactosaminiltransferases/genética , Osteoporose Pós-Menopausa/genética , Polimorfismo de Nucleotídeo Único , Fraturas da Coluna Vertebral/genética , Idoso , Povo Asiático/genética , China/epidemiologia , Feminino , Fator de Crescimento de Fibroblastos 23 , Inativação Gênica , Estudos de Associação Genética , Haplótipos , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Fenótipo , Polipeptídeo N-Acetilgalactosaminiltransferase
7.
Bone ; 50(4): 917-24, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22270056

RESUMO

The Matrilin3 gene (MATN3) encodes an extracellular matrix protein, which modulates chondrocyte differentiation. The aim of this study was to test for association of MATN3 polymorphisms with bone mineral density (BMD), fracture, vertebral fracture, bone turnover or 25-hydroxyvitamin D [25(OH)D] in postmenopausal women. A community-based population of 1488 postmenopausal women was randomly selected in Beijing. The history of fracture and vertebral fracture was obtained via questionnaire and vertebral X-ray respectively. BMD of lumbar spine (2-4), femoral neck and total hip were measured by dual energy X-ray absorptiometry. Serum N-terminal procollagen of type 1 collagen (P1NP), ß-isomerized type I collagen C-telopeptide breakdown products (ß-CTX) and 25(OH)D were quantified. Binary logistic regression revealed that Haplotype-4 was significantly associated with vertebral fracture risk in both additive model (p=0.023, OR=1.521) and dominant model (p=0.028, OR=1.623). The significance remained after 10,000 permutation tests to correct multiple testing (p=0.042). Re-selected age matched vertebral fracture case-control groups revealed similar associations in additive model (p=0.014, OR=1.927, 95%CI=1.142-3.253) and in dominant model (p=0.011, OR=2.231, 95%CI=1.200-4.148). However, no significant association was found between MATN3 polymorphisms and serum ß-CTX, P1NP, 25(OH)D levels, or BMD. In linear regression, Haplotype-2 approached marginal significance in association with femoral neck BMD T-score (p=0.050), but this would account for only 0.2% of BMD variation in our sample. This study suggests that Haplotype-4 of MATN3 is associated with vertebral fracture risk independent of BMD in Chinese postmenopausal women. Efforts should be made to replicate our finding in other, similar and ethnically diverse, populations.


Assuntos
Povo Asiático/genética , Proteínas da Matriz Extracelular/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos/genética , Pós-Menopausa/genética , Fraturas da Coluna Vertebral/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/genética , Estudos de Casos e Controles , China , Colágeno Tipo I/metabolismo , Feminino , Humanos , Desequilíbrio de Ligação/genética , Modelos Logísticos , Proteínas Matrilinas , Pessoa de Meia-Idade , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Pró-Colágeno/metabolismo , Vitamina D/análogos & derivados , Vitamina D/metabolismo
8.
Menopause ; 18(11): 1237-43, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21747303

RESUMO

OBJECTIVE: The aim of this study was to evaluate serum N-aminoterminal propeptide of type I collagen (P1NP), C-terminal telopeptide of type I collagen (ß-CTX), and vitamin D status in healthy Chinese postmenopausal women. The study was also designed to investigate their possible relationships with osteoporosis phenotypes. METHODS: A community-based population of 1,724 postmenopausal women in Beijing was randomly selected. Serum bone turnover markers and 25-hydroxyvitamin D [25(OH)D] were tested by an automated Roche electrochemiluminescence system. Dual-energy x-ray absorptiometry was used to measure bone mineral density (BMD). RESULTS: The mean (SD) values of serum ß-CTX and P1NP were 0.439 (0.210) and 56.7 (27.9) ng/mL, respectively. The 25(OH)D level of postmenopausal women in Beijing was remarkably low (13.2 ± 5.4 ng/mL). Serum ß-CTX and P1NP levels were negatively correlated with BMDs of lumbar spine, femoral neck, and total hip (all P < 0.01). The cubic regression model better fitted the relationships of BMD and bone turnover markers. Serum ß-CTX levels were significantly higher in women with sustained osteoporotic fracture or vertebral fracture (P = 0.006 and 0.012, respectively). No association between P1NP and fracture or vertebral fracture was detected. The same situation applied to 25(OH)D. 25(OH)D was negatively correlated with ß-CTX and P1NP (r = -0.073 and -0.088, P = 0.002 and <0.001, respectively). CONCLUSIONS: Serum ß-CTX and P1NP levels were negatively correlated with BMD. ß-CTX was significantly higher in postmenopausal women with sustained fracture or vertebral fracture. Vitamin D deficiency was highly prevalent in postmenopausal women in Beijing.


Assuntos
Colágeno Tipo I/sangue , Osteoporose Pós-Menopausa/sangue , Fraturas por Osteoporose/sangue , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pós-Menopausa/sangue , Pró-Colágeno/sangue , Vitamina D/análogos & derivados , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Densidade Óssea , Remodelação Óssea/fisiologia , China , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/diagnóstico por imagem , Análise de Regressão , Fraturas da Coluna Vertebral/sangue , Fraturas da Coluna Vertebral/etiologia , Vitamina D/sangue
9.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 28(6): 799-802, 2006 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-17260470

RESUMO

OBJECTIVE: To identify the genotype of RET gene in one multiple endocrine neoplasia type 2A (MEN2A) kindred. METHODS: Genome DNA was extracted from peripheral blood leucocytes. The DNA sequence of gel-purified polymerase chain reaction (PCR) products was determined with the previously reported 6 pairs of primers of PCR amplification of 10, 11, 13, 14, 15, and 16 exons of RETgene. RESULTS: No abnormalities were found in exon 10, 13, 14, 15, and 16. C to G replacement in nucleotide 14 996 of exon 11 was identified in DNA samples obtained from both peripheral blood of 2 affected brothers. This missense point mutation arisen in heterozygosity and caused a substitution of Cys to Trp residue at codon 634 ( Cys 634 Trp) in RET protein. CONCLUSION: The genotype of the family is identified as Cys 634 Trp substitution of RET gene.


Assuntos
Neoplasia Endócrina Múltipla Tipo 2a/genética , Mutação Puntual , Proteínas Proto-Oncogênicas c-ret/genética , Adulto , Éxons/genética , Feminino , Humanos , Masculino , Linhagem , Reação em Cadeia da Polimerase
10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 25(3): 280-4, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12905740

RESUMO

OBJECTIVE: To evaluate the sensitivity and usefulness of 99mTc-sestamibi scintigraphy (SS) and neck ultrasonography (US) as preoperative localization procedures in patients with primary hyperparathyroidism (pHPT). METHODS: 160 patients with proved pHPT in Peking Union Medical College Hospital from June 1983 to June 2002 were studied. There were 107 women(66.9%) and 53 men (33.1%), with a mean age of 38.9 years (10-73 years). 100 patients were underwent SS and 148 patients were underwent US prior to surgery, and the results were compared with operative and histological findings. RESULTS: The sensitivity of SS and US in localization of the enlarged parathyroid glands was 94.0% and 85.1% respectively, and the positive predictive value of SS and US was 100% and 89.1% respectively, the overall sensitivity was 98.9% by combination of SS and US. In solitary parathyroid adenomas group (n = 145), the sensitivity of SS and US was 93.3% and 84.7% respectively; There was no significant difference (P = 0.428) in sensitivity of SS between the parathyroid glands correctly identified and undetected in classical neck location as compared with ectopic parathyroid glands, whereas significantly (P = 0.026) influenced by the US sensitivity. CONCLUSIONS: Different sensitivity exit between SS and VS in preoperative localization in patients with pHPT undergoing parathyroidectomy. The combined use of SS and US could increase the sensitivity of localization technique. Ectopic parathyroid had no influence on the sensitivity of 99mTc-MIBI scanning, but decreased the sensitivity of ultrasonography. The size of parathyroid tumors had effects on the sensitivity of ultrasonography. Otherwise, various conditions causing SS false negative were observed. Some interfere factors should be excluded when SS negative results were encountered in clinical practice.


Assuntos
Hiperparatireoidismo/patologia , Glândulas Paratireoides/patologia , Tecnécio Tc 99m Sestamibi/uso terapêutico , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Hiperparatireoidismo/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Pescoço/diagnóstico por imagem , Glândulas Paratireoides/diagnóstico por imagem , Cuidados Pré-Operatórios , Cintilografia , Sensibilidade e Especificidade , Ultrassonografia
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