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OBJECTIVE: Current risk assessment tools for osteoporosis have inconsistent performance across different cohorts, making them difficult for clinical practice. This study aimed to evaluate a simple screening index comprising years since menopause (YSM) and body mass index (BMI) that identifies postmenopausal Singaporean women with a greater likelihood of low bone mass. METHODS: The study used data from 188 treatment-naïve postmenopausal women. The associations between low bone mass and different demographic variables, including age, YSM and BMI, were assessed using multivariable logistic regression. Diagnostic performance of the calculated screening index was compared to the Osteoporosis Self-Assessment Tool for Asians (OSTA) and the Fracture Risk Assessment Tool (FRAX®). RESULTS: YSM and BMI were significantly associated with low bone mass. The area under the receiver operating characteristic curves was 0.803 for the screening index, 0.759 for the OSTA, 0.683 for the FRAX® (major osteoporotic fracture probability [MOFP]) and 0.647 for the FRAX® (hip fracture probability [HFP]). Non-parametric Spearman's correlation between the screening index and the other models was 0.857 with the OSTA score, 0.694 with the FRAX® (HFP) and 0.565 with the FRAX® (MOFP) (p < 0.0005). CONCLUSIONS: The diagnostic performance of the screening index comprising YSM and BMI was equivalent to the OSTA and the FRAX®. A risk chart was developed for clinicians to identify and recommend subjects for a further dual-energy X-ray absorptiometry scan. Validation of this model in larger and more diverse cohorts is required.
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Osteoporosis , Fracturas Osteoporóticas , Absorciometría de Fotón , Pueblo Asiatico , Índice de Masa Corporal , Densidad Ósea , Femenino , Humanos , Tamizaje Masivo , Menopausia , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/prevención & control , Medición de Riesgo , Factores de Riesgo , Singapur/epidemiologíaRESUMEN
AIM: To examine the role of palmitic acid in lipopolysaccharide (LPS)-stimulated chemotaxis of macrophages and the potential contribution of saturated fatty acid in signalling during the pathogenesis of apical periodontitis. METHODOLOGY: J774, a mouse macrophage cell line, was used in the experiments. After treatment with LPS, proteolytic maturation of sterol regulatory element-binding protein-1c (SREBP-1c) and expression of fatty acid synthase (FASN) were examined by Western analysis. Levels of palmitic acid were measured by reverse phase-high performance liquid chromatography-mass spectrometry. Knockdown of SREBP-1c and FASN was accomplished by small interfering RNA technology. Secretion of CC-chemokine ligand 2 (CCL2) and cellular chemotaxis were assessed by enzyme-linked immunosorbent assay and transwell migration assay, respectively. Sulfo-N-succinimidyl oleate (SSO) treatment was used to inhibit fatty acid signalling in vitro and also in a rat model of apical periodontitis. All data were first subjected to Levene's test. In vitro data were then analysed using ANOVA followed by Tukey's multiple comparison test. Data from animal experiments were analysed by independent t-tests. The significant level was set at 0.05. RESULTS: LPS stimulated proteolytic maturation of SREBP-1c and FASN expression in macrophages and significantly enhanced palmitic acid synthesis (P < 0.05). Knockdown of SREBP-1c attenuated LPS-enhanced FASN expression. Knockdown of FASN significantly suppressed LPS-enhanced palmitic acid synthesis (P < 0.05). LPS and exogenous palmitic acid significantly enhanced CCL2 secretion and macrophage chemotaxis (all P < 0.05). Inhibition of FASN expression significantly alleviated LPS-augmented CCL2 secretion (P < 0.05). SSO significantly suppressed CCL2 secretion and macrophage chemotaxis augmented by LPS and palmitic acid (all P < 0.05). In a rat model of induced apical periodontitis, SSO treatment significantly attenuated progression of apical periodontitis and macrophage recruitment (all P < 0.05). CONCLUSIONS: LPS/SREBP-1c/FASN/palmitic acid signalling contributed to tissue destruction caused by bacterial infection. Modulation of lipid metabolism and signalling may be helpful for the management of apical periodontitis.
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Lipopolisacáridos , Periodontitis Periapical , Animales , Ácidos Grasos , Macrófagos , Ratones , Ratas , Proteína 1 de Unión a los Elementos Reguladores de EsterolesAsunto(s)
Mesenquimoma , Osteomalacia , Neoplasias de los Tejidos Blandos , Humanos , Mesenquimoma/cirugíaRESUMEN
OBJECTIVE: This study evaluated whether supplementations of different vitamins and iron could reduce the serum homocysteine levels in 91 atrophic glossitis (AG) patients. MATERIALS AND METHODS: Atrophic glossitis (AG) patients with concomitant deficiencies of vitamin B12 only (n = 39, group I), folic acid only (n = 10, group II), iron only (n = 9, group III), or vitamin B12 plus iron (n = 19, group IV) were treated with vitamin BC capsules plus deficient hematinics. AG patients without definite hematinic deficiencies (n = 14, group V) were treated with vitamin BC capsules only. The blood homocysteine and hematinic levels at baseline and after treatment till all oral symptoms had disappeared were measured and compared by paired t-test. RESULTS: Supplementations with vitamin BC capsules plus corresponding deficient hematinics for groups I, II, III, IV patients and with vitamin BC capsules only for group V patients could reduce the high serum homocysteine levels to significantly lower levels after a mean treatment period of 8.3-11.6 months (all P-values < 0.05). CONCLUSION: Supplementations with vitamin BC capsules plus corresponding deficient hematinics or with vitamin BC capsules only can reduce the high serum homocysteine levels to significantly lower levels in AG patients.
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Suplementos Dietéticos , Ácido Fólico/uso terapéutico , Glositis/sangre , Hematínicos/uso terapéutico , Homocisteína/sangre , Hierro/uso terapéutico , Lengua/patología , Vitamina B 12/uso terapéutico , Complejo Vitamínico B/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Atrofia/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
OBJECTIVE: Placenta growth factor (PlGF) is associated with the progression and prognosis of oral cancer. MATERIALS AND METHODS: This study used ELISA, quantitative polymerase chain reaction, and Western blotting to study the arecoline-stimulated (PlGF) protein or mRNA expression in human gingival epithelial S-G cells. RESULTS: Arecoline, a major areca nut alkaloid and an oral carcinogen, could stimulate PlGF protein synthesis in S-G cells in a dose- and time-dependent manner. The levels of PlGF protein secretion increased about 3.1- and 3.8-fold after 24-h exposure to 0.4 and 0.8 mM arecoline, respectively. Pretreatment with antioxidant N-acetyl-l-cysteine (NAC) and ERK inhibitor PD98059, but not NF-κB inhibitor Bay 11-7082, JNK inhibitor SP600125, p38 MAPK inhibitor SB203580, and PI3-K inhibitor LY294002, significantly reduced arecoline-induced PlGF protein synthesis. ELISA analyses demonstrated that NAC and PD98059 reduced about 43% and 38% of the arecoline-induced PlGF protein secretion, respectively. However, combined treatment with NAC and PD98059 did not show additive effect. Moreover, 10 µM curcumin and 4 mM NAC significantly inhibited arecoline-induced ERK activation. Furthermore, 10 µM curcumin completely blocked arecoline-induced PlGF mRNA expression. CONCLUSION: Arecoline-induced PlGF synthesis is probably mediated by reactive oxygen species/ERK pathways, and curcumin may be an useful agent in controlling oral carcinogenesis.
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Arecolina/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Encía/citología , Proteínas Gestacionales/biosíntesis , Arecolina/antagonistas & inhibidores , Células Cultivadas , Curcumina/farmacología , Humanos , Factor de Crecimiento PlacentarioRESUMEN
A 21-week-old male untreated control SHR/NCrlNarl rat was found dead during an experiment. Grossly, pulmonary lesions were characterized by multifocal to coalescing firm gray-white nodules randomly scattered on the surface. Microscopically, bronchopneumonia was found with pyogranulomas containing neutrophils, macrophages, and numerous thick-walled yeast cells. Yeast cells, 5 to 25 µm in diameter, with no branching of hyphae were observed by staining with hematoxylin and eosin, Diff-Quik, and periodic acid-Schiff. Furthermore, polymerase chain reaction (PCR) using panfungal and nested PCR primers were used for detection of Blastomyces dermatitidis DNA in the lung tissue. After sequencing and matching with DNA sequences in the GenBank, the sample showed a similarity of 94.6% and 97% to Ajellomyces dermatitidis (B. dermatitidis), respectively. On the basis of these results, probable pulmonary blastomycosis was diagnosed. The origin of the infection in the colony rat is undetermined.
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Blastomyces/genética , Blastomicosis/veterinaria , Pulmón/patología , Ratas Endogámicas SHR , Enfermedades de los Roedores/microbiología , Enfermedades de los Roedores/patología , Animales , Secuencia de Bases , Cartilla de ADN/genética , Resultado Fatal , Técnicas Histológicas/veterinaria , Pulmón/microbiología , Masculino , Datos de Secuencia Molecular , Ratas , Análisis de Secuencia de ADN/veterinaria , Homología de SecuenciaRESUMEN
The article "Circular RNA hsa_circ_0017247 acts as an oncogene in bladder cancer by inducing Wnt/ß-catenin signaling pathway, by C.-T. Han, Q.-Y. Bao, S.-J. Cheng, M. Liu, H.-N. Qian, D. Li, published in Eur Rev Med Pharmacol Sci 2020; 24 (3): 1081-1087-DOI: 10.26355/eurrev_202002_20158-PMID: 32096177" has been withdrawn from the authors since they decided to perform further experiments. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/20158.
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The article "MiR-1266 suppresses the growth and metastasis of prostate cancer via targeting PRMT5, by C.-M. Sun, G.-M. Zhang, H.-N. Qian, S.-J. Cheng, M. Wang, M. Liu, D. Li, published in Eur Rev Med Pharmacol Sci 2019; 23 (15): 6436-6444-PMID: 31378882" has been withdrawn from the authors due to some inaccuracies (some data cannot be repeated by our further research). The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/18525.
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OBJECTIVE: Bladder cancer (BLCA) is the most common genitourinary malignancy in the world. Recent studies have revealed that circular RNAs (circRNAs) are dysregulated in malignant tumors and participate in carcinogenesis. The purpose of our work is to uncover how hsa_circ_0017247 functions in BLCA. PATIENTS AND METHODS: In this research, Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was conducted to monitor hsa_circ_0017247 expression in BLCA samples. Besides, proliferation assay, colony formation assay, and flow cytometry assay were performed in BLCA cells after hsa_circ_0017247 was knocked down. Meanwhile, the Western blot assay was conducted to explore the target signaling pathway of hsa_circ_0017247. Furthermore, tumor formation and metastasis assays were also conducted in vivo. RESULTS: Compared with the adjacent tissues, a significant upregulation in hsa_circ_0017247 expression was observed in BLCA samples. Functional assays showed that the inhibition of cell proliferation was induced via downregulating hsa_circ_0017247 in BLCA in vitro, while the promotion of cell proliferation was induced via downregulating hsa_circ_0017247 in BLCA in vitro. Moreover, the results of further experiments revealed that the targeted proteins in the Wnt/ß-catenin signaling pathway were downregulated via knockdown of hsa_circ_0017247 in BLCA. In addition, tumor formation and metastasis of BLCA were inhibited via knockdown of hsa_circ_0017247 in nude mice. CONCLUSIONS: We discovered a vital regulatory mechanism of hsa_circ_0017247 in BLCA which might serve as a new therapeutic intervention for BLCA patients.
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Oncogenes/fisiología , ARN Circular/biosíntesis , Neoplasias de la Vejiga Urinaria/metabolismo , Vía de Señalización Wnt/fisiología , beta Catenina/metabolismo , Animales , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , ARN Circular/genética , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , beta Catenina/genéticaRESUMEN
Posterior lingual glands consist of two sets of minor salivary glands that serve important functions in oral physiology. To investigate the hypothesis that the hypoglossal nerve provides sympathetic innervation to the posterior lingual glands, we examined ultrastructural changes in the glands following hypoglossal denervation. In the posterior deep lingual glands (of von Ebner), the serous acinar cells showed a decrease in the number of secretory granules and an increase in lipofuscin accumulation. The ratios of cells containing lipofuscin granules were 11.39, 36.49 and 50.46%, respectively, of the control, 3- and 7-day post-axotomy glands (P < 0.001). Intraepithelial phagocytotic activity was increased. The mucous acinar cells in the posterior superficial lingual glands (of Weber) also showed degenerative changes after hypoglossal denervation. One week after nerve transection, marked cytoplasmic vacuolation and fragmentation of organelles were frequently observed. Degenerative changes were also found in unmyelinated axons associated with the glands. We provide the first evidence of the structural and functional connections between the sympathetic component of the hypoglossal nerve and posterior lingual glands.
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Cricetinae/anatomía & histología , Traumatismos del Nervio Hipogloso , Glándulas Salivales Menores/ultraestructura , Lengua/inervación , Animales , Desnervación , Femenino , Nervio Hipogloso/ultraestructura , Masculino , Microscopía Electrónica de Rastreo , Terminales Presinápticos/ultraestructura , Sistema Nervioso Simpático/ultraestructuraRESUMEN
OBJECTIVE: To investigate the incidence and risk factors of post-tooth extraction sepsis in patients without locoregional infection. SUBJECTS AND METHODS: We assessed all claim records of the Taiwanese National Health Insurance program in 2005. Admissions for patients aged > or =16 years containing a discharge diagnosis of sepsis, and who received tooth extraction within 14 days before the admission were identified. Patient charts were reviewed to confirm the diagnosis of sepsis and rule out other infection sources. The relationship between postextraction sepsis (PES) and clinical parameters was analyzed. RESULTS: Thirty-three of the 2 223 971 extraction cases met the criteria of PES, an incidence of 1.48 per 100 000, and seven patients (21.2%) died of the disease. Aging significantly increased the risk of PES (P < 0.001). Pre-existing comorbidities were found in 20 of the 33 cases, with diabetes mellitus and hematologic diseases the most common. The method, number, and position of extraction had no influence on PES incidence. Blood cultures were positive in 25 patients (75.8%) and isolates included species of the Streptococcus, Actinomyces, Klebsiella, Bacteroides, Prevotella, and Enterococcus genera. CONCLUSION: Tooth extraction is associated with a low but significant risk of postoperative sepsis, especially in the elderly and patients with underlying diseases.
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Infección Focal Dental/epidemiología , Complicaciones Posoperatorias/epidemiología , Sepsis/epidemiología , Extracción Dental/efectos adversos , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Infección de la Herida Quirúrgica/epidemiología , Taiwán/epidemiología , Extracción Dental/estadística & datos numéricos , Adulto JovenRESUMEN
OBJECTIVE: To elucidate the correlation between microRNA-1266 (miR-1266) and prostate cancer (PCa) progression, and to investigate the possible underlying mechanism. PATIENTS AND METHODS: The expression level of miR-1266 and protein arginine methyltransferase 5 (PRMT5) in PCa tissues and cell lines was first detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). After up-regulating or down-regulating miR-1266 expression in cells, cell proliferation, migration and invasion abilities were detected. Possible target genes of miR-1266 were predicted and validated by bioinformatics analysis and dual-luciferase reporter gene assay, respectively. Finally, abnormal expression of PRMT5 was ascertained after transfection. RESULTS: MiR-1266 was lowly expressed in PCa tissues and cell lines, whereas PRMT5 exhibited the opposite results. Up-regulated expression of miR-1266 significantly inhibited the proliferation, migration and invasion abilities of PC-3 cells. However, the growth and migration of DU145 cells with low miR-1266 expression were significantly accelerated. Meanwhile, the number of invading cells was significantly increased. PRMT5 was verified as a potential target gene of miR-1266. Furthermore, results found that miR-1266 was negatively correlated with PRMT5. In addition, the expression of PRMT5 was remarkably decreased after miR-1266 overexpression, which could be restored after knockdown of miR-1266. CONCLUSIONS: MiR-1266 inhibits the growth and metastasis of PCa by targeting PRMT5. We may provide a potential and prospective therapeutic target for PCa.
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Proliferación Celular/fisiología , MicroARNs/biosíntesis , Neoplasias de la Próstata/metabolismo , Proteína-Arginina N-Metiltransferasas/biosíntesis , Anciano , Línea Celular Tumoral , Movimiento Celular/fisiología , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteína-Arginina N-Metiltransferasas/antagonistas & inhibidores , Proteína-Arginina N-Metiltransferasas/genéticaRESUMEN
An advanced in vitro cervical tumor model was established by 3D printing to study the epithelial-to-mesenchymal transition (EMT), which is a very important stage of dissemination of carcinoma leading to metastatic tumors. A HeLa/hydrogel grid construct composed of gelatin, alginate, Matrigel and HeLa cells was fabricated by forced extrusion in a layer-by-layer fashion. HeLa cells rapidly proliferated, formed spheroids and presented tumorigenic characteristic in the 3D-printed structure. With the supplement of TGF-ß, aggregated HeLa cells started to disintegrate, and some of them changed into fibroblast-like spindle morphology, which indicated that EMT was induced. The down-regulation of epithelial marker E-cadherin, and up-regulation of mesenchymal markers such as snail, vimentin and N-cadherin were all observed in the 3D-printed model, and performed differently in 3D and 2D models. The TGF-ß induced EMT was inhibited by the treatment of disulfiram and EMT pathway inhibitor C19 in a dose dependent manner, showing great potential for future studies of a therapeutic program towards cervical tumor metastasis.
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Transición Epitelial-Mesenquimal/efectos de los fármacos , Impresión Tridimensional , Factor de Crecimiento Transformador beta/farmacología , Neoplasias del Cuello Uterino/patología , Biomarcadores de Tumor/metabolismo , Forma de la Célula/efectos de los fármacos , Disulfiram/farmacología , Femenino , Células HeLa , Humanos , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/patologíaRESUMEN
OBJECTIVE: To investigate the effect of vascular bradykinin on pancreatic microcirculation and hemorheology in rats with severe acute pancreatitis (SAP). MATERIALS AND METHODS: Ninety male Wistar rats were randomly divided into a blank control group, an SAP group and a vascular bradykinin treatment group. The SAP model was induced by the retrograde injection of 5% sodium taurocholate in the pancreaticobiliary duct. The vascular bradykinin treatment group underwent gastrostomy, with a fine plastic tube placed in the stomach that led out of body through the abdominal wall.Vascular bradykinin was fully dissolved and administered at a dose of 20 U/kg once every 8 h. The pancreatic microcirculatory blood flow volume and velocity, microvascular permeability, hemorheology were evaluated respectively by double-channel laser Doppler flowmetry, the Evans blue leakage test, a blood rheology test instrument. RESULTS: The pancreatic microcirculatory blood flow volume and velocity in the vascular bradykinin treatment group increased gradually after 48 h compared with the SAP group, and the changes were significantly different (p < 0.05). The pancreatic microvascular permeability of the vascular bradykinin treatment group was significantly reduced after 48 h compared with the SAP group (p < 0.05). The low shear rate blood viscosity, hematocrit and erythrocyte aggregation index of the vascular bradykinin treatment group were significantly decreased after 48 h compared with the SAP group (p < 0.05). CONCLUSIONS: Vascular bradykinin can improve pancreatic microcirculation and hemorheology in rats with severe acute pancreatitis.
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Bradiquinina/administración & dosificación , Hemorreología/efectos de los fármacos , Microcirculación/efectos de los fármacos , Páncreas/efectos de los fármacos , Pancreatitis/tratamiento farmacológico , Índice de Severidad de la Enfermedad , Animales , Hemorreología/fisiología , Infusiones Parenterales , Masculino , Microcirculación/fisiología , Páncreas/irrigación sanguínea , Pancreatitis/patología , Ratas , Ratas Wistar , Resultado del TratamientoRESUMEN
BACKGROUND: Cadaveric liver transplantation is effective for nonresectable early hepatocellular carcinoma. However, the scarcity of cadaveric organs has prompted some centers to use living donors, which guarantees transplantation, but entails a risk to the donor. In the absence of controlled trials, decision analysis can be used to help explicate the tradeoffs involved when considering living donor versus cadaveric liver transplantation for nonresectable early hepatocellular carcinoma. METHODS: Using a Markov model, a hypothetical cohort of patients with Child's A cirrhosis and a single 3.5-cm tumor received one of three strategies: 1) no transplant; 2) intent to perform cadaveric liver transplantation; or 3) living donor liver transplantation. Data were obtained from natural history and retrospective studies. All probabilities in the model were varied simultaneously using a Monte Carlo simulation. RESULTS: Living-donor liver transplantation was the best strategy, improving life expectancy by 4.5 years compared with cadaveric liver transplantation. This strategy remained dominant even when varying severity of cirrhosis, age, tumor doubling time, tumor growth pattern, blood type, regional transplant volume, initial tumor size, and rate of progression of cirrhosis. CONCLUSIONS: Living-donor liver transplantation should confer a substantial survival advantage for patients with compensated cirrhosis and non-resectable early stage hepatocellular carcinoma.
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Carcinoma Hepatocelular/cirugía , Cirrosis Hepática/cirugía , Neoplasias Hepáticas/cirugía , Trasplante de Hígado/métodos , Cadáver , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/patología , Técnicas de Apoyo para la Decisión , Humanos , Esperanza de Vida , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/patología , Trasplante de Hígado/mortalidad , Donadores Vivos , Cadenas de Markov , Persona de Mediana Edad , Tasa de Supervivencia , Donantes de TejidosRESUMEN
The chromosomal imbalances in nine cases of primary non-small cell lung cancer (NSCLC) and two cell lines derived from normal human bronchial epithelial (HBE) tissue were identified by comparative genomic hybridization (CGH). Gain of material from 3q and loss of 3p material were the most frequent changes in the primary tumors. Other commonly found imbalances included gain of material from 1q, 7p, 8q, 9q, 17q and 20q, and losses involving 4, 5q, 8p, 10 and 13q. High level gain was found in two cases, both encompassing the 3q23-q27 region. Loss of 3p was also found in both of the HBE cell lines suggesting that loss of one or more tumor supressor genes on 3p may be important for epithelial transformation and could be involved in the earlier stages of lung cancer development.
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Carcinoma de Pulmón de Células no Pequeñas/genética , Aberraciones Cromosómicas/genética , Cromosomas Humanos Par 3 , Neoplasias Pulmonares/genética , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/patología , Cromosomas Humanos Par 3/genética , ADN de Neoplasias/análisis , Femenino , Humanos , Cariotipificación , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Fenotipo , Células Tumorales CultivadasRESUMEN
The majority of human lung cancers originate from the carcinogenesis of bronchial epithelial cells. To study the malignant progression of human bronchial epithelial cells, we established a SV40T-transformed human bronchial epithelial cell line, and observed some biological and genetic changes of the cell line at different passages. In a 2-year culture, this cell line was approaching malignancy without obvious senescence. Cells in a later passage proliferated faster and required less growth factors than those of an early passage. After continued passaging, these cells were resistant to the terminal squamous differentiation effects of serum, and many of the cells grew anchorage independently. However, no tumor formed after cells were injected into nude mice. Some genetic alterations were found accompanying those morphological changes, such as 3p- and activation of c-myc, c-erbB-2 and bcl2, suggesting that those genetic alterations may contribute to the carcinogenesis of human bronchial epithelial cells at an early stage. This cell line should be particularly useful for studying the progression of human lung cancers.
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Bronquios/citología , Bronquios/virología , Transformación Celular Viral , Virus 40 de los Simios , Animales , Northern Blotting , Neoplasias de los Bronquios/genética , Neoplasias de los Bronquios/patología , Diferenciación Celular/fisiología , Línea Celular Transformada , Células Epiteliales/citología , Células Epiteliales/virología , Genes Virales , Genotipo , Humanos , Ratones , Ratones Desnudos , Fenotipo , Plásmidos , ARN/análisis , Virus 40 de los Simios/genética , Células Madre/citologíaRESUMEN
Salicylate was found to uniquely induce a 27-kDa protein in Mycobacterium tuberculosis complex organisms but not in Mycobacterium smegmatis or Escherichia coli. The structural analogue antitubercular para-amino-salicylate also induced the 27-kDa protein but to a somewhat lower level than salicylate. Other structural analogues such as benzoic acid and acetyl salicylic acid (aspirin) did not induce the 27-kDa protein. Western blot analysis indicated that the 27-kDa protein was localized mainly in the cytoplasm. The 27-kDa protein was not expressed at different growth phases in the absence of salicylate. The 27-kDa protein was identified as a putative benzoquinone methyltransferase (Rv0560c), which has several homologues in the M. tuberculosis genome. The cloned 27-kDa gene was found to express constitutively in E. coli, M. smegmatis and BCG with or without salicylate.
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Proteínas Bacterianas/biosíntesis , Metiltransferasas/biosíntesis , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/enzimología , Salicilatos/farmacología , Ácido Aminosalicílico/farmacología , Proteínas Bacterianas/genética , Benzoquinonas/metabolismo , Medios de Cultivo , Inducción Enzimática , Metiltransferasas/genética , Mycobacterium tuberculosis/crecimiento & desarrolloRESUMEN
This study was conducted to investigate the alteration of some characteristics of E. coli O157:H7 subjected to various periods of storage at -5, -18 and -28 degrees C. Results revealed that the low-temperature treatments increased the susceptibility of E. coli O157:H7 to crystal violet, bile salt, sodium chloride and ethanol. In general, the susceptibility of E. coli O157:H7 subjected to storage at -18 degrees C increased most significantly. The susceptibility of E. coli O157:H7 to the tested agents increased as the period of low-temperature storage extended, regardless of storage temperature. Among the various nitrogen and carbon sources tested, tryptone and soytone were the most effective nitrogen sources, while glucose and maltose were the most effective carbon sources for the growth of the low-temperature stressed cells. When growing the stressed E. coli O157:H7 in media containing the same nitrogen source or carbon source, their lag period increased as the time of frozen storage increased. It was also noted that in general, the recovery of the low-temperature stressed E. coli O157:H7 was highest on tryptic soy agar followed by Modified eosin methylene blue agar, while recovery on MaConkey sorbitol agar and Modified MaConkey sorbitol agar was lowest.
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Ácidos y Sales Biliares/farmacología , Escherichia coli O157/crecimiento & desarrollo , Etanol/farmacología , Violeta de Genciana/farmacología , Cloruro de Sodio/farmacología , Carbono/metabolismo , Recuento de Colonia Microbiana , Medios de Cultivo , Escherichia coli O157/efectos de los fármacos , Escherichia coli O157/aislamiento & purificación , Congelación , Nitrógeno/metabolismo , Factores de TiempoRESUMEN
For centuries green tea has been a widely consumed beverage throughout the world. It is known to contain a number of pharmacologically active compounds. In this study water extracts of green tea (WEGT) and their major constituents, green tea polyphenols (GTP), were examined for antimutagenic activity. WEGT and GTP were found to significantly inhibit the reverse mutation induced by benzo[alpha]pyrene (BP), aflatoxin B1 (AFB1), 2-aminofluorene, and methanol extracts of coal tar pitch in Salmonella typhimurium TA100 and/or TA98 in the presence of a rat-liver microsomal activation system. GTP also inhibited gene forward mutation in V79 cells treated with AFB1 and BP, and also decreased the frequency of sister-chromatid exchanges and chromosomal aberrations in V79 cells treated with AFB1. The addition of GTP during and after nitrosation of methylurea resulted in a dose-dependent inhibition of mutagenicity. Studies to define the mechanism of the antimutagenic activity of GTP suggest that it may affect carcinogen metabolism, DNA adduct formation, the interaction of ultimate carcinogen or the scavenging of free radicals.