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1.
J Surg Oncol ; 127(6): 905-920, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36826370

RESUMO

BACKGROUND AND OBJECTIVES: We aim to evaluate the analgesic efficacy and safety of erector spinae plane block (ESPB) for postoperative analgesia in breast cancer surgeries. METHODS: PubMed, Web of Science, CBM, Embase, Cochrane, Wanfang, VIPP, and CNKI were searched to identify published eligible randomized controlled trials. The primary results were the postoperative 24 h morphine consumption and pain scores, while the secondary outcomes included pain scores at other times, press times of patient-controlled intravenous analgesia (PCIA), times to request for first rescue analgesia, the incidence of request for rescue analgesia, opioid-related complications, nerve blocks related complications and patient satisfaction. RESULTS: We included 20 studies meeting the inclusion criteria, which involved 1293 participants. The morphine consumption and the pain scores during 24 h postoperatively were significantly decreased in the ESPB group versus the control group (p < 0.00001). Furthermore, ESPB also reduced pain scores at other time points, press times of PCIA, and times to first rescue analgesia requirement. Meanwhile, there was a lower incidence of postoperative nausea and vomiting, and skin pruritus in the ESPB group than in the control group. CONCLUSIONS: Compared to general anesthesia alone, ESPB combined with general anesthesia can effectively reduce the postoperative pain intensity within 48 h and opioid consumption within 24 h after breast cancer surgery, and reduce the incidence of opioid and nerve blocks related complications.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Analgésicos Opioides , Dor Pós-Operatória , Analgesia Controlada pelo Paciente , Derivados da Morfina
2.
Biochem J ; 475(17): 2713-2725, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-30049895

RESUMO

Cryptomeridiol, a typical eudesmane diol, is the active principle component of the antispasmodic Proximol. Although it has been used for many years, the biosynthesis pathway of cryptomeridiol has remained blur. Among terpenoid natural products, terpenoid cyclases are responsible for cyclization and generation of hydrocarbon backbones. The cyclization is mediated by carbocationic cascades and ultimately terminated via deprotonation or nucleophilic capture. Isoprene precursors are, respectively, converted into hydrocarbons or hydroxylated backbones. A sesquiterpene cyclase in Tripterygium wilfordii (TwCS) was determined to directly catalyze (E,E)-farnesyl pyrophosphate (FPP) to unexpected eudesmane diols, primarily cryptomeridiol. The function of TwCS was characterized by a modular pathway engineering system in Saccharomyces cerevisiae The major product determined by NMR spectroscopy turned out to be cryptomeridiol. This unprecedented production was further investigated in vitro, which verified that TwCS can directly produce eudesmane diols from FPP. Some key residues for TwCS catalysis were screened depending on the molecular model of TwCS and mutagenesis studies. As cryptomeridiol showed a small amount of volatile and medicinal properties, the biosynthesis of cryptomeridiol was reconstructed in S. cerevisiae Optimized assays including modular pathway engineering and the CRISPR-cas9 system were successfully used to improve the yield of cryptomeridiol in the S. cerevisiae The best engineered strain TE9 (BY4741 erg9::Δ-200-176 rox1::mut/pYX212-IDI + TwCS/p424-tHMG1) ultimately produced 19.73 mg/l cryptomeridiol in a shake flask culture.


Assuntos
Carbono-Carbono Liases , Microrganismos Geneticamente Modificados , Naftalenos/metabolismo , Proteínas de Plantas , Saccharomyces cerevisiae , Sesquiterpenos de Eudesmano/biossíntese , Tripterygium/genética , Carbono-Carbono Liases/genética , Carbono-Carbono Liases/metabolismo , Engenharia Metabólica , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sesquiterpenos de Eudesmano/genética , Tripterygium/enzimologia
3.
J Asian Nat Prod Res ; 20(7): 595-604, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28276759

RESUMO

The biosynthetic pathways of phytosterols and steroidal saponins are located in two adjacent branches which share cycloartenol as substrate. The rate-limiting enzyme S-adenosyl-L-methionine-sterol-C24-methyltransferase 1 (SMT1) facilitates the metabolic flux toward phytosterols. It catalyzes the methylation of the cycloartenol in the side chain of the C24-alkyl group, to generate 24(28)-methylene cycloartenol. In this study, we obtained two full-length sequences of SMT1 genes from Pari polyphylla, designated PpSMT1-1 and PpSMT1-2. The full-length cDNA of PpSMT1-1 was 1369 bp long with an open reading frame (ORF) of 1038 bp, while the PpSMT1-2 had a length of 1222 bp, with a 1005 bp ORF. Bioinformatics analysis confirmed that the two cloned SMTs belong to the SMT1 family. The predicted function was further validated by performing in vitro enzymatic reactions, and the results showed that PpSMT1-1 encodes a cycloartenol-C24-methyltransferase, which catalyzes the conversion of cycloartenol to 24-methylene cycloartenol, whereas PpSMT1-2 lacked this catalytic activity. The tissue expression patterns of the two SMTs revealed differential expression in different organs of Paris polyphylla plants of different developmental stage and age. These results lay the foundation for detailed genetic studies of the biosynthetic pathways of steroid compounds, which constitute the main class of active substances found in P. polyphylla.


Assuntos
Melanthiaceae/enzimologia , Melanthiaceae/genética , Metiltransferases/genética , Sequência de Bases , Catálise , Clonagem Molecular , DNA de Plantas/química , DNA de Plantas/genética , Medicamentos de Ervas Chinesas , Isoenzimas/genética , Isoenzimas/metabolismo , Modelos Moleculares , Estrutura Molecular , Fases de Leitura Aberta , Fitosteróis/metabolismo , Triterpenos/metabolismo
4.
Zhongguo Zhong Yao Za Zhi ; 42(1): 88-93, 2017 Jan.
Artigo em Zh | MEDLINE | ID: mdl-28945030

RESUMO

Kaurenoic acid oxidase involved in biosynthesis pathway of gibberellin. According to the transcriptome database, the specific primers were designed and used in cloning the full-length cDNA of TwKAO, the bioinformatic analysis of the sequence was performed. The qRT-PCR were used to detect the expression level of TwKAO after MeJA treatment.The full-length cDNA of the TwKAO was 1 874 bp encoding a polypeptide of 487 amino acids.The calculate molecular weight was about 56.02 kDa,and the theoretical isoelectric point (pI) was 8.89. The relative expression level of TwKAO was deduced by MeJA and reached the highest at 12 h after the treatment.Plant tissue expression analysis indicated that, TwKAO expressed the highest in leaves,while lowest in roots.For the first time, we cloned and analyzed the expression characteristics of TwKAO, which laid a foundation for deep analysis of growing development and terpenoid secondary metabolites in T. wilfordii.


Assuntos
Oxigenases de Função Mista/genética , Proteínas de Plantas/genética , Tripterygium/enzimologia , Clonagem Molecular , DNA Complementar , Regulação da Expressão Gênica de Plantas , Filogenia , Tripterygium/genética
5.
Zhongguo Zhong Yao Za Zhi ; 42(7): 1312-1318, 2017 Apr.
Artigo em Zh | MEDLINE | ID: mdl-29052392

RESUMO

In this study, we cloned a monoterpene synthases, TwMS from Tripterygium wilfordii suspension cells. TwMS gene contained a 1 797 bp open reading frame (ORF), encoding a polypeptide of 579 amino acids, which deduced isoelectric point (pI) was 6.10 and the calculated molecular weight was 69.75 kDa. Bioinformation analysis showed that the sequence of TwMS was consistent with the feature of monoterpene synthases. Differential expression analysis revealed that the relative expression level of TwMS increased significantly after being induced by methyl jasmonate (MeJA). The highest expression level occurred at 24 h. TwMS protein was successfully expressed in Escherichia coli BL21 (DE3), which laid the foundation for identifying the function of T. wilfordii monoterpene synthases.


Assuntos
Liases Intramoleculares/genética , Proteínas de Plantas/genética , Tripterygium/genética , Sequência de Aminoácidos , Clonagem Molecular , Filogenia , Tripterygium/enzimologia
6.
Zhongguo Zhong Yao Za Zhi ; 42(2): 220-225, 2017 Jan.
Artigo em Zh | MEDLINE | ID: mdl-28948723

RESUMO

Based on the transcriptome data, the study cloned full-length cDNA of TwGPPS1 and TwGPPS2 genes from Tripterygium wilfordii suspension cells and then analyzed the bioinformation of the sequence and protein expression. The cloned TwGPPS1 has a 1 278 bp open reading frame (ORF) encoding a polypeptide of 425 amino acids. The deduced isoelectric point (pI) was 6.68, a calculated molecular weight was about 47.189 kDa. The full-length cDNA of the TwGPPS2 contains a 1 269 bp open reading frame (ORF) encoding a polypeptide of 422 amino acids. The deduced isoelectric point (pI) was 6.71, a calculated molecular weight was about 46.774 kDa.The entire reading frame of TwGPPS1,2 was cloned into the pET-32a(+) vector and expressed in E. coli BL21 (DE3) cells to obtain the TwGPPS protein, which laid a basis for further study on the regulation of terpenoid secondary metabolism and biological synthesis.


Assuntos
Difosfatos/metabolismo , Diterpenos/metabolismo , Geraniltranstransferase/genética , Proteínas de Plantas/genética , Tripterygium/enzimologia , Clonagem Molecular , DNA Complementar , Filogenia , Metabolismo Secundário , Tripterygium/genética
7.
Yao Xue Xue Bao ; 51(11): 1799-805, 2016 11.
Artigo em Zh | MEDLINE | ID: mdl-29908530

RESUMO

24-Alkyl sterols are the major players in the control of membrane component and plant growth. In this paper, we cloned an important rate-limiting enzyme: sterol-C-24-methyl transferase (SMT) in the sterol biosynthetic pathway according to the transcriptome data of Tripterygium wilfordii. suspension cells, whose full-length cDNA was 1 631 bp with an open reading frame of 1 080 bp, encoding a protein of 359 amino acids. It was estimated that theoretical isoelectric point (p I) was 6.43 and the molecular mass was 40.0 kDa. Bioinformatics analysis attributed the SMT gene to SMT2 family. The expression vector was constructed as the pMAL-c2x-TwSMT2 plasmid and the recombinant protein was expressed in E. coil BL21(DE3) competent cells. After methyl jasmonate treatment, the relative expression level of Tw SMT2 has improved significantly in 24 h. SDS-PAGE electrophoresis and Western Blot showed that protein of TwSMT2 in BL21 (DE3) strain was expressed after induction by IPTG. In this study, TwSMT2 was cloned for the first time and the recombinant protein was expressed, which lay the foundation for elucidation of the sterol biosynthetic pathway of Tripterygium wilfordii in the future.


Assuntos
Proteínas de Plantas/genética , Transferases/genética , Tripterygium/genética , Sequência de Aminoácidos , Clonagem Molecular , Biologia Computacional , DNA Complementar , Tripterygium/enzimologia
8.
Yao Xue Xue Bao ; 51(11): 1799-805, 2016 11.
Artigo em Zh | MEDLINE | ID: mdl-29908531

RESUMO

24-Alkyl sterols are the major players in the control of membrane component and plant growth. In this paper, we cloned an important rate-limiting enzyme: sterol-C-24-methyl transferase (SMT) in the sterol biosynthetic pathway according to the transcriptome data of Tripterygium wilfordii. suspension cells, whose full-length c DNA was 1 631 bp with an open reading frame of 1 080 bp, encoding a protein of 359 amino acids. It was estimated that theoretical isoelectric point (pI) was 6.43 and the molecular mass was 40.0 kDa. Bioinformatics analysis attributed the SMT gene to SMT2 family. The expression vector was constructed as the pMAL-c2x-TwSMT2 plasmid and the recombinant protein was expressed in E. coil BL21(DE3) competent cells. After methyl jasmonate treatment, the relative expression level of TwSMT2 has improved significantly in 24 h. SDS-PAGE electrophoresis and Western Blot showed that protein of TwSMT2 in BL21 (DE3) strain was expressed after induction by IPTG. In this study, Tw SMT2 was cloned for the first time and the recombinant protein was expressed, which lay the foundation for elucidation of the sterol biosynthetic pathway of Tripterygium wilfordii in the future.

9.
Inorg Chem ; 53(14): 7438-45, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-24959700

RESUMO

We have applied crystal engineering as a tool to study the solid-state transformation from molecular salts to coordination complexes via mechanochemical dehydrochlorination reactions. The -(CH2)n- (n = 2, 3) alkyl chains were introduced into the bibenzylamine moiety to form the two nitrogen bases N,N,N',N'-tetrabenzylethylenediamine (L(1)) and N,N,N',N'-tetrabenzylpropydiamine (L(2)), which were self-assembled with tetrachlorometalates to form a series of supramolecular salts through second-sphere coordination. Single crystals of salts [L(1)]2H(+)·[CuCl4](2-)·solvent (1) and [L(2)]2H(+)·[XCl4](2-)·solvent (2-4; X = Cu, Hg, Zn) were obtained and their structures determined by single-crystal X-ray diffraction. The effect of different alkyl chains (two and three -CH2- units) on the solid-state reactivity showed that the chelating complexes resulting from the mechanochemical dehydrohalogenation reaction depend on the formation of quasi-chelating hydrogen-bonding salts. Quantum-mechanical calculations have been used to gain insight in this mechanochemical dehydrohalogenation reaction, demonstrating that not only is size matching between reactants is important but also conformational energies, intermolecular interactions, and the symmetry of frontier molecular orbitals play an important role.

10.
Artigo em Zh | MEDLINE | ID: mdl-22730686

RESUMO

OBJECTIVE: To analyze the prevalence characteristics and influence factors of pneumoconiosis of workers exposed to dusts in an iron mine, to provide the base of preventive measures for pneumoconiosis of iron mine. METHODS: The subjects of cohort study were all workers exposed to dusts for at least one year registered in an iron mine during 1960 to 1974, and followed-up to the end in 2003. The cases with pneumoconiosis were diagnosed by the local diagnosis group of pneumoconiosis, according to the national diagnostic criteria of pneumoconiosis. The risk factors were analyzed with Cox risk model. RESULTS: A total of 3647 miners were included in the cohort study and were followed up by 132 574.4 person years. There were 316 cases with pneumoconiosis, and the incidence of pneumoconiosis for a year was 0.24 per thousand. There were 274 cases (86.7%) with pneumoconiosis in workers exposed to dusts before 1960, the incidence of pneumoconiosis for a year was 0.40 per thousand, which was significantly higher than that (0.07 per thousand) of workers exposed to dusts after 1960. The average latency of pneumoconiosis was 26.0 +/- 7.3 years. The average durations of upgrade from stage 0(+) to I , I to II and II to III were 5.3 +/- 3.2, 6.6 +/- 5.2 and 11.3 +/- 5.0 years, respectively. However, 164 cases with pneumoconiosis were diagnosed after ceasing exposure to dusts for mean 8.3 years. The risk of pneumoconiosis in iron miners increased with exposure doses, and there was an obvious dose-effect relationship. The average cumulative exposure dose of cases with pneumoconiosis was 173.7 +/- 91.6 mg/m3 x y, which was significantly higher than that (112.1 +/- 64.8 mg/m3 x y) of workers without pneumoconiosis. Also the tuberculosis (HR = 5.9, P < 0.001) and smoking (HR = 1.7, P < 0.01) were the main risk factors. CONCLUSION: There was an obvious dose-effect relationship between the cumulative exposure dose and pneumoconiosis incidence. Tuberculosis and smoking were the main risk factors influencing the pneumoconiosis incidence.


Assuntos
Exposição Ocupacional , Pneumoconiose/epidemiologia , Adulto , Idoso , Poluentes Ocupacionais do Ar/análise , Estudos de Coortes , Poeira/análise , Feminino , Humanos , Incidência , Ferro , Masculino , Pessoa de Meia-Idade , Mineração , Prevalência , Fatores de Risco
11.
Dalton Trans ; 49(46): 16662-16666, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33196721

RESUMO

A facile and efficient cyclization of sodium aminodiboranate to construct a boron-nitrogen-hydrogen ring is presented. This new strategy can be developed into a general method to prepare aminodiborane and its derivatives. Theoretical calculations show that a one-step cyclization mechanism is favored, where the dihydrogen bond plays an important role.

12.
Clin Cancer Res ; 14(21): 6996-7003, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18980995

RESUMO

PURPOSE: To characterize the expression of sphingosine kinase-1 (SPHK1) in human astrocytomas and to investigate the association between SPHK1 expression and progression of astrocytomas. EXPERIMENTAL DESIGN: The expression of SPHK1 in normal human astrocytes, astrocytoma cell lines, and four pairs of matched astrocytoma tissues and their adjacent normal brain tissues were detected by quantitative reverse transcription-PCR and Western blot. In addition, SPHK1 protein expression was examined in 243 cases of histologically characterized astrocytomas by immunohistochemistry. Statistical analyses were applied to test for prognostic and diagnostic associations. RESULTS: SPHK1 in astrocytoma cell lines was elevated at both mRNA and protein levels, and the SPHK1 mRNA and protein were significantly up-regulated by up to 6.8- and 40-fold, respectively, in primary astrocytomas compared with those in the adjacent noncancerous brain tissues. Immunohistochemical analysis showed that 100 of 243 (41.2%) paraffin-embedded archival astrocytoma biopsies exhibited high expression of SPHK1. Statistical analysis suggested that the up-regulation of SPHK1 was significantly correlated with the histologic grade of astrocytoma (P=0.000) and that patients with high SPHK1 level exhibited shorter survival time (P<0.001). Multivariate analysis revealed that SPHK1 up-regulation might be an independent prognostic indicator for the survival of patients with astrocytoma. CONCLUSIONS: SPHK1 might represent a novel and useful prognostic marker for astrocytoma and play a role during the development and progression of the disease.


Assuntos
Astrocitoma/metabolismo , Astrocitoma/mortalidade , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
13.
Fa Yi Xue Za Zhi ; 24(6): 437-8, 2008 Dec.
Artigo em Zh | MEDLINE | ID: mdl-19241972

RESUMO

OBJECTIVE: To investigate the polymorphism of the TPH gene T3792A locus in Han ethnic group of north China and its application value in forensic science. METHODS: The polymorphism of T3792A locus of the TPH gene was analyzed by the ASPCR of blood samples from 173 unrelated individuals of north Chinese Han population. RESULTS: The distribution of the T3792A locus polymorphism of the TPH gene in Han ethnic group of north China followed the Hardy-Weinberg law, with the allele A and T gene frequency of 0.486 and 0.514, respectively. CONCLUSION: The TPH gene T3792A locus shows a very good genetic polymorphism, and may be applied to individual identification and paternity testing.


Assuntos
Povo Asiático/genética , Genética Forense , Polimorfismo Genético , Triptofano Hidroxilase/genética , China/etnologia , Frequência do Gene , Humanos , Paternidade
14.
Artigo em Zh | MEDLINE | ID: mdl-19358753

RESUMO

OBJECTIVE: To study the effect of mining operations on the mental health of residents living in a mining area in Hubei province. METHODS: Villagers (n = 93) living in the mining area were compared with a control group of residents (n = 101) in mental health status, and knowledge of environment and health. The mental health status of villagers was assessed using the Symptom Checklist 90 (SCL-90), State-Trait Anxiety Inventory (STAI); The knowledge of environment and health was evaluated using a self-designed questionnaire. The urine and hair samples were collected from some subjects. The lead, cadmium, arsenic, copper and zinc contents were detected as well as the total protein, NAG, d-ALA in the urine. RESULTS: The occurrence rate of lead, cadmium, arsenic exposure symptoms was significantly higher in the exposed group than in the control group. The urine cadmium, the hair cadmium, the hair arsenic and hair lead were significantly higher in the exposed group than in the control group (P < 0.05). The positive symptom detection rate of SCL-90 in the exposed group was 8.60% compared with 0.99% of the control group. For the SCL-90, the total scale, somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, paranoid ideation, psychoticism, other symptom in the exposed groups were significantly higher than those in the control group (P < 0.05), indicating the status of the psychological hygiene of the exposed group was worse than the control group. The total S-AI (anxiety) score and the sex-specific value in the exposed group were higher than the control group (P < 0.05, P < 0.01), which showed that the anxiety of the exposed group was more evident. The total T-AI score and the sex-specific value in women of the exposed group were significantly higher than the control group (P < 0.01), showing that the anxiety were more significant in the exposed group, especially the women of the exposed group. CONCLUSION: The mental health status of the residents who living in a mining area is affected and they have a higher S-AI and T-AI scale than those living a non-mining area.


Assuntos
Ansiedade/epidemiologia , Exposição Ambiental/efeitos adversos , Nível de Saúde , Saúde Mental , Metais Pesados/efeitos adversos , Mineração , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Meio Ambiente , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
15.
Fa Yi Xue Za Zhi ; 23(6): 444-5, 2007 Dec.
Artigo em Zh | MEDLINE | ID: mdl-18402117

RESUMO

OBJECTIVE: To study the distribution of the tryptophan hydroxylase (TPH) gene-T457C locus polymorphism in Han ethnic group in northern China and to find its applicable value in forensic science. METHODS: Genomic DNA samples, extracted from 180 unrelated individuals in northern Chinese Han population, were analyzed by PCR-RFLP. RESULTS: The discrimination power (DP) value and the power of exclusion (PE) value of the TPH gene-T457C locus were 0.624 and 0.187, respectively. The allele frequency showed significant difference from that of French people (P=0.04). CONCLUSION: Polymorphism of the TPH gene-T457C locus could show ethnic and regional differences. It has a potential to be used in forensic science.


Assuntos
Povo Asiático/genética , Frequência do Gene , Polimorfismo Genético , Triptofano Hidroxilase/genética , Alelos , China/etnologia , Eletroforese em Gel de Poliacrilamida , Genótipo , Humanos , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA
16.
Artigo em Zh | MEDLINE | ID: mdl-16824343

RESUMO

OBJECTIVE: To investigate the main diseases jeopardizing the health of the iron miners and to explore the relationship between dust exposure and malignancies as well as other diseases. METHODS: A retrospective study with a cohort of 7,469 workers employed between January 1, 1972 and December 31, 1974 in Daye Iron Ore Mine Co. in Hubei Province was conducted. Standardized mortality ratio (SMR) was calculated for the main causes of death using Chinese national mortality rates for reference. RESULTS: All subjects were followed up through December 31, 2003 with an accumulation of 199, 108.0 person years. A total of 1,752 workers died. The cumulative mortality was 23.5%. The cancers, cerebrovascular diseases, non-malignant respiratory diseases and cardiovascular diseases were main diseases that threatened workers' life span. The SMR for all subjects was a little higher than expected based on the Chinese national mortality rates. The diseases causing the significantly higher death rate were the nasopharynx cancer, liver cancer, lung cancer, pneumoconiosis and accident with SMR 1.84, 1.51, 1.83, 14.94 and 1.25 respectively. Increased mortality was observed among dust-exposed workers in the cohort. The cumulative mortality from all causes such as stomach cancer, lung cancer, nonmalignant respiratory diseases, cardiovascular diseases and accident in dust exposed workers were significantly increased compared with those in non-exposure workers with RR 1.35, 1.83, 1.61, 2.27, 1.34 and 1.69 respectively. CONCLUSION: The risk factors especially dust exposure affect the health and lifespan of the iron mine workers.


Assuntos
Poeira , Ferro , Mineração , Neoplasias/mortalidade , Exposição Ocupacional/efeitos adversos , Adulto , Doenças Cardiovasculares/mortalidade , Causas de Morte , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Respiratórias/mortalidade , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/mortalidade
17.
Zhonghua Shao Shang Za Zhi ; 27(4): 269-73, 2011 Aug.
Artigo em Zh | MEDLINE | ID: mdl-22097303

RESUMO

OBJECTIVE: To fabricate polyvinyl alcohol (PVA)/chitosan hybrid nanofibrous scaffolds owning the similar physiological structure of ECM, and to observe its biodegradation behavior in vivo and in vitro. METHODS: (1) The PVA nanofibrous scaffold and PVA/chitosan hybrid nanofibrous scaffold were fabricated by electrospinning technique, and then they were crosslinked by glutaraldehyde vapor method. The morphology of both scaffolds was observed by scanning electron microscope (SEM). (2) Biodegradation experiment in vitro: the samples of two scaffolds with size of 2 cm x 2 cm were placed into phosphate-buffer saline (PBS) fluid under 37.0 degrees C water for incubation, and then they were dried to observe morphologic changes under SEM on post incubation day (PID) 3, 7, and 14. (3) Biodegradation experiment in vivo: 48 Wistar rats were divided into PVA group and PVA/chitosan group according to the random number table, with 24 rats in each group. PVA or PVA/chitosan nanofibrous scaffold was implanted into subcutaneous tissue on both sides of back in rats of both groups, with 4 scaffolds in each rat. The scaffold samples were harvested to observe morphologic changes with HE staining on post operation day (POD) 3, 7, 14, and 28. RESULTS: (1) After crosslinking, the surface of fibers in PVA and PVA/chitosan hybrid nanofibrous scaffolds were smooth, and the diameters of fibers were similar, ranging from 200 to 300 nm, with high porosity. (2) Biodegradation experiment in vitro showed that the morphologic changes in fiber was respectively swelling, dissolution, fusion in PVA nanofibrous scaffold on PID 3, 7, 14, and that in PVA/chitosan hybrid nanofibrous scaffold was respectively swelling, dissolution and fragmentation, and disappearance. (3) Biodegradation experiment in vivo showed that the morphologic changes in scaffold structure was respectively loosening, fuzziness of edges, degradation, and disappearance in PVA group and PVA/chitosan group on POD 3, 7, 14, 28. CONCLUSIONS: PVA/chitosan hybrid nanofibrous scaffolds can be prepared with electrospinning technique, and it has an appropriate biodegradation rate compatible with tissue reconstruction after crosslinking.


Assuntos
Materiais Biocompatíveis , Quitosana/química , Álcool de Polivinil/química , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Células Cultivadas , Quitosana/síntese química , Teste de Materiais , Álcool de Polivinil/síntese química , Ratos , Ratos Wistar
18.
J Forensic Sci ; 54(6): 1304-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19804530

RESUMO

Reducing amplicon sizes has become a major strategy for analyzing degraded DNA typical of forensic samples. However, amplicon sizes in current mini-short tandem repeat-polymerase chain reaction (PCR) and mini-sequencing assays are still not suitable for analysis of severely degraded DNA. In this study, we present a multiplex typing method that couples ligase detection reaction with PCR that can be used to identify single nucleotide polymorphisms and small-scale insertion/deletions in a sample of severely fragmented DNA. This method adopts thermostable ligation for allele discrimination and subsequent PCR for signal enhancement. In this study, four polymorphic loci were used to assess the ability of this technique to discriminate alleles in an artificially degraded sample of DNA with fragment sizes <100 bp. Our results showed clear allelic discrimination of single or multiple loci, suggesting that this method might aid in the analysis of extremely degraded samples in which allelic drop out of larger fragments is observed.


Assuntos
Degradação Necrótica do DNA , Impressões Digitais de DNA/métodos , Fragmentação do DNA , Reação em Cadeia da Ligase , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Alelos , Primers do DNA , Sondas de DNA , Genótipo , Humanos
19.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 25(5): 450-3, 2007 Oct.
Artigo em Zh | MEDLINE | ID: mdl-18072557

RESUMO

OBJECTIVE: To evaluate the influence of different types of posts and cores on the final color of the IPS-Emperss 2 crown. METHODS: Five types of posts and cores (Cerapost with Empress cosmo, Cerapost with composite resin, gilded Ni-Cr alloy, gold alloy and Ni-Cr alloy) were made. The shifts in color of three points of IPS-Empress 2 crown surface (cervical, middle and incisal) with different posts and cores was measured with a spectroradiometer (PR-650). RESULTS: The L* a* b* values of zirconium oxide and gilded Ni-Cr alloy posts and cores with ceramic crown were the highest. The L* a* values of zirconium oxide posts composite cores were higher while the b* values were lower. The L* a* b* values of Ni-Cr alloy were lower than that of gold alloy and were the lowest. CONCLUSION: In combination with IPS-Empress 2 crown, zirconium oxide posts are suitable for routine use in the anterior dentition, and gilded Ni-Cr alloy and gold alloy posts and cores can be recommended for clinical practice. Ni-Cr alloy posts and cores can not be recommended for clinical practice.


Assuntos
Coroas , Técnica para Retentor Intrarradicular , Cor , Resinas Compostas , Porcelana Dentária , Humanos , Compostos de Lítio , Zircônio
20.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 24(5): 441-3, 2006 Oct.
Artigo em Zh | MEDLINE | ID: mdl-17315657

RESUMO

OBJECTIVE: To investigate the effects of luting agent on the final color of glass infiltrated alumina ceramic restorations. METHODS: 12 plate-shaped specimens with 12.5 mm in diameter and 0.5 mm thickness were fabricated from GI-II (color IG2). Vitadur alpha veneering porcelain (color A2) with 1.0 mm thickness was fired to GI- II glass/alumina composite. 12 plate-shaped background specimens simulating the metal alloy post-and-core 12.5 mm in diameter and 2 mm thickness were also made from Ni-Cr alloy. All-ceramic specimens were luted to the metal alloy by Zinc Phosphate cement, glass ionomer cement and composite resin. The color shifts of the specimens were measured by colorimeter. RESULTS: Luting agents had effect on the final color of restorations. The influence of composite resin was least, followed by glass ionomer cement and Zinc Phosphate cement. The color difference between with and without Zinc Phosphate cement could be identified by the eye. CONCLUSION: To reduce the effect of luting agents, composite resin is recommended to all-ceramic restorations' adhesion.


Assuntos
Óxido de Alumínio , Cimentos de Resina , Cerâmica , Cor , Resinas Compostas , Cimentos Dentários , Porcelana Dentária , Cimentos de Ionômeros de Vidro , Humanos
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