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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(1): 24-30, 2024 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-38062690

RESUMO

Objective: To analyze the clinical data of a case of lung adenocarcinoma with Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) resistance transforming into sarcoma, and to conduct a literature review to improve the understanding of the resistance mechanism. Histological transformation is a unique form of acquired resistance of EGFR-TKIs in non-small cell lung cancer (NSCLC). Thereinto, the transformation of small cell carcinoma is more common, and the transformation of sarcoma is rarely reported. Methods: Clinicopathological data on the treatment process, pathological features, and clinical outcome of the patient with EGFR-TKIs-resistance lung adenocarcinoma transforming into sarcoma were collected. The literature was reviewed to analyze the pathogenetic mechanism for sarcomatoid carcinoma or sarcoma transformation after drug resistance of adenocarcinoma, as well as the clinical characteristics of the patients and the corresponding therapeutic schemes. Results: We reported a patient with lung adenocarcinoma who developed EGFR-T790M mutation after first-line treatment with icotinib and sarcoma transformation after second-line treatment with almonertinib. Chemotherapy, radioactive particle implantation, antiangiogenic therapy and immunotherapy were followed, but the results were unsatisfactory. There was no report of EGFR-TKIs-resistant lung adenocarcinoma transforming into sarcoma. Among the 14 reports of adenocarcinoma transforming into sarcomatoid carcinoma, 8 cases had EGFR mutation, 3 cases had ALK mutation, 2 cases had ROS1 mutation, and 1 case had no asscoiated sensitive mutation. The median survival of 14 patients with adenocarcinoma transforming to sarcomatoid carcinoma was only 3 months. Conclusions: Sarcoma transformation can be one of the forms of drug resistance in patients with lung adenocarcinoma with EGFR-TKIs. The prognosis of patients with adenocarcinoma after transformation into sarcoma is poor.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Sarcoma , Humanos , Adenocarcinoma/genética , Adenocarcinoma de Pulmão/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/genética , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Sarcoma/genética , Sarcoma/tratamento farmacológico
2.
Public Health ; 225: 110-119, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37924635

RESUMO

OBJECTIVES: This study aimed to establish an occupational disease surveillance system by identifying high-risk industries for silicosis in Taiwan using a national database linkage approach. METHODS: The study was based on a comprehensive analysis of benefit claims from the National Labor Insurance Research Database and medical records from the National Health Insurance Research Database between 2004 and 2020, providing coverage for more than 88.5% of the workforce and 99.9% of citizens. Silicosis was defined as having received compensation for labor insurance benefits or having received a diagnosis of silicosis (International Classification of Diseases, 10th Revision: J62 or International Classification of Diseases, Ninth Revision: 502). The study used the International Standard Industrial Classification of All Economic Activities for industry-specific classification. Cox proportional hazard models were used to compare the silicosis incidence and risk among each industry and identify high-risk industries for silicosis. RESULTS: This study analyzed 1466 cases of silicosis between 2004 and 2020 and found that 28 industries had incidence rates of over 40 cases per 100,000 workers, indicating more than double the risk of developing silicosis. Of these industries, 14 were considered high risk (relative risk of over four times). Among these, this study identified industries rarely mentioned in the past, such as wholesale of brick, sand, cement, and products, artistic creation, landscape construction, and materials recovery. Stratification by years of work experience reveals those industries such as quarrying of stone, sand, clay, and other mining, construction of buildings, landscape construction, site preparation, foundation and structure construction, building completion and finishing, manufacture of ships, boats, and floating structures, and plumbing, heat, and air conditioning installation display higher hazard ratios for individuals with <10 years of work experience. CONCLUSIONS: The current surveillance system has identified certain industries that are at a higher risk of developing silicosis, which could be used for future occupational epidemiological surveys and targeted preventive measures in these sectors.


Assuntos
Doenças Profissionais , Exposição Ocupacional , Silicose , Humanos , Incidência , Areia , Taiwan/epidemiologia , Silicose/epidemiologia , Silicose/diagnóstico , Silicose/prevenção & controle , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(2): 129-132, 2020 Feb 06.
Artigo em Chinês | MEDLINE | ID: mdl-32074697

RESUMO

Objective: To explore the association between the frequency of prenatal care in childbearing aged women and risk of small for gestational age (SGA) among neonatal twins in Shaanxi Province. Methods: From July to December 2013, a total of 30 027 childbearing aged women, who were pregnant from January 2010 to November 2013 and had definite outcomes, were selected from 30 districts (counties) of Shaanxi Province by using the multi-stage random sampling method. The questionnaires with a face-to-face survey method were used to retrospectively collect demographic information, pregnancy history, lifestyle during pregnancy, disease history, nutritional supplements, and health care during pregnancy. Information on the gestational age and birth weight of the newborn were obtained by consulting the medical certificate of birth and were registered as twin A and twin B by birth order. Finally, 356 childbearing aged women and their twin babies with complete data were included in the analysis. A generalized estimation equation model was used to analyze the association between the frequency of prenatal care and the risk of SGA among neonatal twins. Results: The age of childbearing aged women was (27.44±4.68) years old, of which 79.49% (283 women) were rural residents and 44.38% (158 women) had seven or more times prenatal care. The gestational age and birth weight were (37.64±2.51) weeks and (2 510±497) g, respectively. The prevalence of SGA was 51.40% (183/356) for twin A and 53.37% (190/356) for twin B, respectively. The prevalence of SGA was 44.30% (70/158) for twin A with seven or more times prenatal care and 42.41% (67/158) for twin B with seven or more times prenatal care, which was lower than that for twins with less than seven times prenatal care, respectively [57.07% (113/198) and 62.12% (123/198)] (P values were 0.017 and <0.001). The results of generalized estimation equation model suggested that compared to those with less than seven times prenatal care, after adjusting for parity, birth order, place of residence, maternal age, occupation, education, family wealth index, passive smoking, pregnancy-induced hypertension syndrome, folic acid, and iron supplement during perinatal period, and gender of the newborn, the OR (95%CI) of risk of SGA among childbearing aged women with seven or more times prenatal care was 0.60 (0.40-0.91). Conclusion: Seven or more times prenatal care could reduce the risk of SGA among neonatal twins in Shanxi Province.


Assuntos
Recém-Nascido Pequeno para a Idade Gestacional , Cuidado Pré-Natal/estatística & dados numéricos , Gêmeos/estatística & dados numéricos , Adulto , China/epidemiologia , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Retrospectivos , Medição de Risco , Adulto Jovem
4.
Neurogastroenterol Motil ; 29(11)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28585346

RESUMO

BACKGROUND: Tacr2 is one of the G protein-coupled receptors(GPCRs) that mediate the biological actions of tachykinins. It is abundantly expressed in the gastrointestinal (GI) system and is thought to play an important role in GI motility, secretion, and visceral sensitivity. Previously, the physiological and pathophysiological functions of Tacr2 were mainly studied using Tacr2 selective agonists or antagonists. Here, we seek to investigate the effect of Tacr2 disruption in mice to provide further insights. METHODS: The Tacr2 knockout mice were generated by homologous recombination and the phenotypic changes of the Tacr2-null mice were analyzed and compared with their wild type (wt) littermates. KEY RESULTS: Increased food retention was detected in Tacr2-/- mice. The stomach of Tacr2-/- mice had thinner muscularis externa and less neurons in the myenteric plexus. The stomach and small intestine exhibited longer duration of electrical field stimulation (EFS)-induced inhibition in the gastric fundus and decreased frequency of migrating motor complex (MMC), respectively. Neuronal nitric oxide synthase (nNOS) and vasoactive intestinal polypeptide (VIP) were significantly up-regulated due to Tarc2 deficiency, contributing to enhanced nitric oxide (NO) signaling in the stomach of Tacr2-/- mice. Intraperitoneal application of 7-nitroindazole (7-NI) to Tacr2-/- mice effectively relieved the gastric emptying disturbance. Moreover, Creb and NF-κB signalings were involved in the regulation of these physiological changes initiated by Tacr2 deficiency. CONCLUSIONS & INFERENCES: Tacr2 negatively regulated the expression of nNOS and VIP both in vivo and in vitro. Its ablation in mice elevated the expression of nNOS and VIP, enhanced NO signaling and changed the Creb and NF-κB signalings, finally leading to the gastric emptying disturbance of Tacr2-/- mice.


Assuntos
Esvaziamento Gástrico , Mucosa Gástrica/metabolismo , Receptores da Neurocinina-2/fisiologia , Estômago/fisiopatologia , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Fundo Gástrico/fisiopatologia , Regulação da Expressão Gênica , Intestino Delgado/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Fenótipo , Antro Pilórico/fisiopatologia , Receptores da Neurocinina-2/genética , Receptores da Neurocinina-2/metabolismo , Transdução de Sinais , Estômago/patologia , Peptídeo Intestinal Vasoativo/metabolismo
5.
Lung Cancer ; 80(3): 333-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23510626

RESUMO

BACKGROUND: The X-box binding protein 1 (XBP1) is a critical transcription factor in the endoplasmic reticulum stress response, which is essential for the maintenance of cellular homeostasis. Here, we investigated whether the regulatory variant rs2269577 of the XBP1 gene influences clinical outcome in advanced non-small cell lung cancer (NSCLC) patients undergoing platinum-based chemotherapy. PATIENTS AND METHODS: We recruited 663 Chinese patients with advanced NSCLC treated with platinum-based regimens and assessed the association between rs2269577 and clinical outcome. Subsequent functional analyses, including real-time quantitative PCR and dual-luciferase assays, were performed to explore possible molecular mechanisms. RESULTS: The G/G genotype of rs2269577 was significantly associated with severe gastrointestinal toxicity compared with the homozygous C/C genotype (P=0.012, odds ratio=2.755), particularly in the female, performance status 0-1, and adenocarcinoma subgroups. No significant relevance was found between rs2269577 and treatment efficacy. In gastric epithelial cells, in vitro molecular analyses demonstrated that XBP1 mRNA expression levels decreased after treatment with cisplatin and the G allele of rs2269577 weakened the transcriptional activity of the XBP1 promoter. CONCLUSION: This is the first study to evaluate the effect of XBP1 polymorphism on severe chemotherapy-related adverse outcomes in platinum-treated advanced NSCLC patients using both pharmacogenomics and functional molecular analyses.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proteínas de Ligação a DNA/genética , Trato Gastrointestinal/patologia , Neoplasias Pulmonares/tratamento farmacológico , Platina/administração & dosagem , Fatores de Transcrição/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , China , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Genótipo , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polimorfismo Genético , Regiões Promotoras Genéticas , Fatores de Transcrição de Fator Regulador X , Proteína 1 de Ligação a X-Box
6.
Tumour Biol ; 34(2): 953-61, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23412975

RESUMO

Valosin-containing protein (VCP), or p97, is a member of the ATP-binding protein family, and is involved in numerous cellular events, such as, protein degradation, membrane fusion, and chaperone activity. VCP has been demonstrated playing a critical role in non-small-cell lung cancer (NSCLC) pathogenesis and progression recently. We investigated the association between VCP polymorphisms and clinical outcome in advanced NSCLC patients undergoing platinum-based chemotherapy. We recruited 663 Chinese advanced NSCLC patients who were treated with platinum-based regimens, and using their clinical data, we assessed the efficacy and side effects of their treatment. Three tag-single nucleotide polymorphisms (SNPs) of VCP were genotyped. SNP rs2074549 showed a significant association with severe neutropenia. Its G/G genotype increased the risk of grade 3 or 4 neutropenia compared with wild-type homozygotes A/A (P = .001, odds ratio = 2.975). Haplotype association analysis revealed that CGA was associated with the increased incidence of severe neutropenia (P = .041, odds ratio = 1.439). However, no significant relationship was found between the presence of VCP polymorphisms and treatment efficacy when objective response, progression-free survival, and overall survival (OS) were evaluated. Our study is the first to provide evidence that VCP polymorphisms are associated with a severe chemotherapy-related adverse outcome in platinum-treated advanced NSCLC patients.


Assuntos
Adenosina Trifosfatases/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Proteínas de Ciclo Celular/genética , Neoplasias Pulmonares/mortalidade , Compostos Organoplatínicos/efeitos adversos , Polimorfismo de Nucleotídeo Único/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , DNA/sangue , DNA/genética , Feminino , Seguimentos , Haplótipos/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neutropenia/induzido quimicamente , Reação em Cadeia da Polimerase , Prognóstico , Taxa de Sobrevida , Proteína com Valosina
7.
Dis Esophagus ; 24(3): 131-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20946132

RESUMO

Foreign bodies should not be allowed to remain in the esophagus beyond 24 hours after presentation. However, some patients with esophageal foreign body ingestion do not come to the hospital immediately and may delay medical intervention from the time of ingestion. The aim of this study was to investigate the outcomes of adults with suspected esophageal foreign body ingestion according to the time of ingestion and types of foreign bodies. A total of 326 adult patients (151 men and 175 women) were analyzed, and divided into two groups according to the time period: within or beyond 24 hours from ingestion to endoscopic intervention. A total of 172 patients (52.7%) were found to have ingested foreign bodies; 73.5% were removed smoothly, 10.3% were treated by push technique and 16.0% with failed retrieval received alternative treatments. A higher proportion of patients in the beyond-24 hours group suffered from odynophagia (25.9 vs. 12.9%, P < 0.05). Negative identification of esophageal foreign bodies was more frequent in the beyond-24 hours group (67 vs. 40.2%, P < 0.05), but these patients showed higher proportions of esophageal ulcers (21.1 vs. 7.2%, P < 0.05). The beyond-24 hours group also showed a significantly higher rate of foreign bodies in the lower esophagus (40.0 vs. 15.3%, P < 0.05). Patients with esophageal food bolus impaction had significant delayed endoscopic intervention, longer therapeutic endoscopic time, higher proportions of esophageal cancer, stricture and fewer complications. Endoscopic intervention within 24 hours from the time of ingestion should be considered early in adults, because delaying intervention may produce more symptomatic esophageal ulcerations with odynophagia.


Assuntos
Esôfago , Corpos Estranhos/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Esofagoscopia , Feminino , Alimentos , Corpos Estranhos/complicações , Corpos Estranhos/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
8.
Nat Prod Res ; 22(6): 554-63, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18415865

RESUMO

The characterization of an L-amino acid oxidase purified from Agkistrodon acutus snake venom was investigated. An L-amino acid oxidase (LAAO) was purified from A. acutus snake venom through DEAE Sepharose F.F. and Source 30 S chromatography. The molecular mass of this enzyme was determined by SDS-PAGE, size exclusion chromatography, and mass spectrometry. Substrate specificity, cytotoxicity, antitumor activity in vivo, and apoptosis-inducing activity were assayed. The LAAO purified from A. acutus snake venom was designated as ACTX-6. It is a covalently bound homodimer and its molecular mass is about 96 kDa. This enzyme preferred to oxidize hydrophobic L-amino acids; the best substrates were L-Met, L-Leu, L-Trp, and L-Phe. ACTX-6 demonstrated cytotoxicity in vitro and could inhibit tumor growth in vivo. Flow cytometry analysis showed that it could markedly increase accumulation of sub-G1 phase, which suggested that this enzyme could induce apoptosis. ACTX-6 could effectively inhibit tumor growth and it is a potential substance to develop into an antitumor drug.


Assuntos
Agkistrodon/metabolismo , Antineoplásicos/isolamento & purificação , Venenos de Crotalídeos/enzimologia , L-Aminoácido Oxidase/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Venenos de Crotalídeos/química , Feminino , Citometria de Fluxo , Humanos , L-Aminoácido Oxidase/química , L-Aminoácido Oxidase/farmacologia , Masculino , Camundongos , Peso Molecular , Neoplasias do Colo do Útero/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Ind Microbiol Biotechnol ; 30(12): 677-81, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14648344

RESUMO

The operation of a fed-batch culture is more complicated than that of batch or continuous culture. Thus, an appropriate feeding strategy for fed-batch cultures should be carefully designed. In this study, a simple feeding strategy for fed-batch culture of Bacillus thuringiensis based on "motile intensity" is described. The feeding strategy consisted of two steps: (1) initiating feeding at the peak of motile intensity; (2) terminating feeding at low motile intensity (or non-motility) of the cells. In addition, the motile intensity of B. thuringiensis was used to determine the optimum environmental conditions (pH, temperature, and dissolved oxygen) and optimum medium composition. Using this fed-batch strategy, the production of thuringiensin increased 34% compared with batch culture using the same environmental conditions and medium composition. The proposed strategy for fed-batch culture helps to avoid overfeeding of substrate and facilitates on-line control. A comparison of several alternative strategies for fed-batch culture demonstrated that strategies such as glucose-stat and DO-stat result in a lower productivity than that obtained using the motility intensity method.


Assuntos
Adenosina/análogos & derivados , Bacillus thuringiensis/crescimento & desenvolvimento , Bacillus thuringiensis/metabolismo , Meios de Cultura , Microbiologia Industrial/métodos , Adenosina/biossíntese , Carbono/metabolismo , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Oxigênio/metabolismo , Açúcares Ácidos
10.
J Assist Reprod Genet ; 19(2): 90-3, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11958512

RESUMO

An unusual case of retroperitoneal ectopic pregnancy is reported. The patient, a 34 year old nulligravida, underwent IVF/ET following bilateral salpingectomy. A small, degenerating, intrauterine gestational sac suggested failing intrauterine pregnancy. There was no intraperitoneal free fluid. On Day 41 after ET, the patient was hospitalized because of acute epigastric pains. A pseudocyst of the head of pancreas was demonstrated by CT scan. A day later, exploratory laparotomy, because of a precipitous drop in the hemoglobin, revealed a massive retroperitoneal hematoma and an embryo in the gestational sac attached to the head of pancreas and major blood vessels. The patient did well following surgery. The mechanisms of retroperitoneal embryo migration are discussed and literature is reviewed.


Assuntos
Fertilização in vitro/efeitos adversos , Gravidez Ectópica/etiologia , Adulto , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Pâncreas , Cavidade Peritoneal , Gravidez , Gravidez Ectópica/diagnóstico por imagem , Ultrassonografia
11.
Appl Microbiol Biotechnol ; 58(2): 175-7, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11876409

RESUMO

Cultivation of Bacillus thuringiensis for thuringiensin production is a mixed-growth-associated system. Cultivation conditions should be different during the cell growth stage and production stage. In this study, agitation speed and aeration rate were varied during the exponential growth phase and stationary phase in order to investigate the effect of shear stress via agitation on cultivation of B. thuringiensis for thuringiensin production. It was found that shear stress had a significant effect on thuringiensin production during the stationary phase. By decreasing the agitation speed during the stationary phase, product formation was increased up to 43%.


Assuntos
Adenosina/análogos & derivados , Adenosina/biossíntese , Bacillus thuringiensis/crescimento & desenvolvimento , Bacillus thuringiensis/fisiologia , Técnicas Bacteriológicas , Meios de Cultura , Fermentação , Oxigênio/farmacologia , Açúcares Ácidos
12.
Can J Microbiol ; 47(3): 269-75, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11315118

RESUMO

A segment of DNA containing the L-glutamate oxidase (gox) gene from Streptomyces platensis NTU3304 was cloned. The entire nucleotide sequence of the protein-coding portion consisting of 2130 bp (710 codons, including AUG and UGA) of the cloned DNA fragment was determined. The gox gene contained only one open reading frame (ORF) which coded for a 78-kDa polypeptide, the precursor of active extracellular Gox. Mature Gox is composed of three subunits, designated as alpha, beta, and gamma, with molecular masses of 39, 19, and 16 kDa, respectively. Analyses of the N-terminal amino acid sequences of the subunits revealed that the order of subunits in the precursor polypeptide encoded by the ORF, from N-terminus to C-terminus, is alpha-gamma-beta. The presence of the flavin adenine dinucleotide (FAD)-binding motif place Gox as a member of the flavoenzyme family. Furthermore, a negative effect of glucose on the biosynthesis of Gox was observed when it was used as carbon source.


Assuntos
Aminoácido Oxirredutases/genética , Precursores de Proteínas/genética , Streptomyces/genética , Aminoácido Oxirredutases/biossíntese , Sequência de Aminoácidos , Sequência de Bases , Genes Bacterianos , Biblioteca Genômica , Dados de Sequência Molecular , Sequências Reguladoras de Ácido Nucleico , Análise de Sequência de DNA , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Streptomyces/enzimologia
13.
Mutat Res ; 409(1): 37-48, 1998 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-9806501

RESUMO

The repair of UV-induced DNA damage in the phosphoenolpyruvate carboxykinase (PEPCK) gene was studied in primary cultures of hepatocytes isolated from young (6-month-old) and old (24-month-old) rats fed ad libitum and old rats fed a calorie-restricted diet. Incubation of the hepatocytes with cAMP rapidly induced PEPCK transcription and mRNA levels 4- to 5-fold. In absence of cAMP, the repair of the PEPCK fragment was similar in cultured hepatocytes isolated from young and old rats fed ad libitum. However, cAMP significantly increased the percentage of cyclobutane pyrimidine dimers (CPDs) removed from the PEPCK fragment 12 h after UV-irradiation in cultured hepatocytes isolated from young rats fed ad libitum. This increase was due to an increase in the repair of the transcribed strand of the PEPCK fragment. In contrast, cAMP did not increase the repair of the PEPCK fragment in cultured hepatocytes isolated from old rats fed ad libitum in spite of an increase in PEPCK transcription. Thus, it appears that the coupling of transcription and DNA repair is compromised in cultured hepatocytes isolated from old rats fed ad libitum. However, cultured hepatocytes isolated from old rats fed a calorie-restricted diet showed an induction in the rate of repair of the transcribed strand of the PEPCK fragment by cAMP that was similar to hepatocytes isolated from young rats fed ad libitum.


Assuntos
AMP Cíclico/análogos & derivados , Reparo do DNA/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Tionucleotídeos/farmacologia , Transcrição Gênica/efeitos dos fármacos , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Separação Celular , AMP Cíclico/farmacologia , DNA/genética , DNA/metabolismo , DNA/efeitos da radiação , Dano ao DNA , Reparo do DNA/genética , Dieta , Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Fígado/citologia , Masculino , Ratos , Ratos Endogâmicos F344 , Mapeamento por Restrição
14.
J Craniofac Surg ; 9(4): 404-9, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9780938

RESUMO

The aim of this study was to determine the outcome of autotransplanting part of the metopic suture to a defect in the coronal suture in a pig model and to explore further the concept of functioning and nonfunctioning recipient sites. The authors harvested 15-mm x 10-mm bone grafts, incorporating a part of the metopic suture, in 10 Yorkshire pigs under general anesthesia. The authors immediately autotransplanted the grafts to a surgically created defect along the line of the coronal suture. Both donor and graft were either covered with pericranium or left bare. Radiopaque titanium markers were inserted to assess growth 1) of the transplanted suture; 2) across both coronal sutures; and 3) across the metopic suture. Serial radiographs were taken immediately after surgery and at 3-week intervals. The pigs were then killed at 21 weeks. The cranium was harvested, and blocks of donor site and graft were taken, incorporating the embedded titanium markers. Histologic analysis confirmed graft take in all pigs. All grafts continued to function as active cranial sutures with no growth disturbance compared with the contralateral coronal suture (P = 0.953). There was also regeneration of the donor defect, as confirmed by histologic analysis, with no growth disturbance across the metopic suture (P = 0.972). Pericranium did not alter graft take or subsequent growth (P = 0.964). However, pericranium resulted in a much smaller defect (P = 0.045). These results show that after autotransplanting a cranial suture to replace another cranial suture, the graft continues to grow and function as a cranial suture to meet the functional demands of the new recipient site. Pericranium has a significant effect on calvarial regeneration but does not affect cranial suture autotransplantation.


Assuntos
Suturas Cranianas/transplante , Animais , Regeneração Óssea , Transplante Ósseo/métodos , Suturas Cranianas/crescimento & desenvolvimento , Suínos , Transplante Autólogo
15.
Ann Acad Med Singap ; 21(5): 640-8, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1292393

RESUMO

A bank explosion in a neighbouring country over 1000 km away resulted in ten badly burned victims being airlifted to the Burns Centre, Singapore General Hospital (BCSGH) for treatment. The severely injured included patients with 90%, 80%, 74%, 66%, 45%, 33% and 31% burns. Nine had respiratory burns (four severe, one moderate, four mild). One patient died, thus, the mortality rate for the six most severely injured was 16.7%. This differs from predicted mortality rates of 78% according to McCoy or 54% according to Thompson, Herndon et al. The factors contributing to this result were the small size of the disaster, the use of an established Burns Mass Disaster plan and an individual management policy that incorporates carefully monitored fluid resuscitation, recognition of respiratory burns with early treatment by intubation thus pre emptying complications, early surgery and a multidisciplinary approach to complications such as infection and renal failure. The average length of stay was 43 days (range 5-122 days). The cost of the hospitalisation of the ten casualties was $312,317.00.


Assuntos
Traumatismos por Explosões/terapia , Queimaduras por Inalação/terapia , Explosões , Adulto , Unidades de Queimados/organização & administração , Planejamento em Desastres , Serviços Médicos de Emergência , Feminino , Humanos , Malásia , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente , Singapura , Transporte de Pacientes
16.
Ann Acad Med Singap ; 21(2): 176-89, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1519881

RESUMO

Fifteen Oriental noses were examined macrosurgically and microscopically. Five soft tissue layers overlying the osseocartilaginous framework are identified: the skin, the subcutaneous areolar plane, the vascular-fibromuscular layer, the deep areolar plane and perichondrium/periosteum. Two natural planes of dissection are represented by these areolar planes which separate the nose into an overlying skin envelope, a vascular-fibromuscular layer and an underlying osseocartilaginous framework. The cartilaginous framework provides projection, support and shape to the dorsum and tip of the nose but not to the alar lobule as this is devoid of cartilage. As there is no cartilage in the Alar lobule, the term 'Alar Cartilage' is misleading and the term 'Tip Cartilage' is introduced to replace it. The skin of the nose is specialised and has the ability to retain its shape even after dissection. This is due to an arrangement of elastin fibres in the upper dermis and the subcutaneous areolar plane which confers elasticity to the skin especially in the region of the Alar lobule which is a skin and fibromuscular sandwich. The vascular fibromuscular layer is like a sheet draping the osseocartilaginous framework. The main arteries of the nose lie on this layer. Injection studies of the blood supply reveal many arterial variations but always a distinct alar artery, columellar artery and alar plexus that have not been previously named. The alar groove is a junction between the alar lobule which is soft tissue alone and the tip which is soft tissue, supported by cartilage. The alar groove lies over the lateral edge of the tip cartilage and here there is muscular attachment to the fibromuscular layer.


Assuntos
Povo Asiático , Nariz/anatomia & histologia , Antropometria , Cartilagem/anatomia & histologia , China/etnologia , Dissecação , Estudos de Avaliação como Assunto , Músculos Faciais/anatomia & histologia , Humanos , Masculino , Nariz/irrigação sanguínea , Valores de Referência , Singapura , Pele/anatomia & histologia
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