RESUMEN
BACKGROUND: Gaseous by-products generated by surgical devices - collectively referred to as 'surgical smoke' - present the hazard of transmitting infective viruses from patients to surgical teams. However, insufficient evidence exists to evaluate and mitigate the risks of SARS-CoV-2 transmission via surgical smoke. AIM: To demonstrate the existence and infectivity of human coronavirus RNA in surgical smoke using a model experiment and to evaluate the possibility of lowering transmission risk by filtration through a surgical mask. METHODS: Pelleted HeLa-ACE2-TMPRSS2 cells infected with human coronavirus were incised by electric scalpel and ultrasonic scalpel, separately. A vacuum system was used to obtain surgical smoke in the form of hydrosol. Reverse transcription-quantitative polymerase chain reaction was used to analyse samples for the presence of viral RNA, and infectivity was determined through plaque assay. Furthermore, a surgical mask was placed centrally in the vacuum line to evaluate its ability to filter viral RNA present in the surgical smoke. FINDINGS: In this model, 1/106 to 1/105 of the viral RNA contained in the incision target was detected in the collected surgical smoke. The virus present in the smoke was unable to induce plaque formation in cultured cells. In addition, filtration of surgical smoke through a surgical mask effectively reduced the amount of viral RNA by at least 99.80%. CONCLUSION: This study demonstrated that surgical smoke may carry human coronavirus, though viral infectivity was considerably reduced. In clinical settings, surgical mask filtration should provide sufficient additional protection against potential coronavirus, including SARS-CoV-2, infection facilitated by surgical smoke.
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COVID-19 , Humo , Humanos , Máscaras , ARN Viral/genética , SARS-CoV-2 , Humo/efectos adversosRESUMEN
Once a localized reaction (beaking) was detected, discontinuation of bisphosphonates (BPs) and switching to vitamin D supplementation or teriparatide therapy effectively improved its shape. When the localized reaction was high, of the pointed type, and/or accompanied by prodromal pain, the risks of complete and incomplete atypical femoral fracture increased and consideration of prophylactic fixation for such patients was required. INTRODUCTION: Femoral localized reaction (localized periosteal thickening of the lateral cortex, beaking) is reported to precede atypical femoral fractures (AFFs) and to develop in 8-10% of patients with autoimmune diseases taking BPs and glucocorticoids. The aims of the present study were to retrospectively investigate the shapes of localized reaction to consider how to manage the condition. METHODS: Twenty femora of 12 patients with autoimmune diseases who were on BPs and glucocorticoids exhibited femoral localized reaction. The heights of localized reaction were measured and the shapes classified as pointed, arched, and other. Localized reaction changes were divided into three categories: deterioration, no change, and improvement. A severe form of localized reaction was defined; this was associated with prodromal pain, de novo complete AFF, or incomplete AFF with a fracture line at the localized reaction. RESULTS: The mean height of localized reaction was 2.3 ± 0.8 mm (range, 1.0-3.7 mm) and the pointed type was 35%. Localized reaction was significantly higher (3.3 ± 0.8 vs. 2.1 ± 0.7 mm; p = 0.003) and the pointed type more common (78 vs. 27%; p = 0.035) in those with the severe form of localized reaction. Seven patients with localized reactions discontinued BPs just after localized reaction was detected, but five continued on BPs for 2 years. Localized reaction deterioration was more common in patients who continued than discontinued BPs (100 vs. 29%; p = 0.027). After 2 years, all patients had discontinued BPs and localized reaction did not deteriorate further in any patient. CONCLUSIONS: Once a localized reaction was detected, discontinuation of BPs and switching to vitamin D supplementation or teriparatide therapy effectively improved it. When the localized reaction was high, of the pointed type, and/or accompanied by prodromal pain, the risks of complete and incomplete AFF increased and consideration of prophylactic fixation for such patients was required.
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Enfermedades Autoinmunes/tratamiento farmacológico , Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Fracturas del Fémur/inducido químicamente , Glucocorticoides/efectos adversos , Adulto , Anciano , Biomarcadores/metabolismo , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/uso terapéutico , Huesos/metabolismo , Difosfonatos/administración & dosificación , Difosfonatos/uso terapéutico , Esquema de Medicación , Femenino , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/patología , Fracturas por Estrés/inducido químicamente , Fracturas por Estrés/diagnóstico por imagen , Fracturas por Estrés/patología , Glucocorticoides/administración & dosificación , Glucocorticoides/uso terapéutico , Humanos , Persona de Mediana Edad , Radiografía , Estudios RetrospectivosRESUMEN
SUMMARY: The incidence of beaking, which has been reported to precede atypical femoral fracture, was high and increased over 2 years in patients with autoimmune diseases who were taking bisphosphonates and glucocorticoids. Regular femoral X-rays are strongly recommended to screen for beaking, and bisphosphonate drug holidays should be considered. INTRODUCTION: Atypical femoral fractures (AFFs) have been recently recognized as complications associated with bisphosphonate (BP) use. AFFs are considered to be stress fractures; localized periosteal thickening of the lateral cortex is often present at the fracture site; this thickening is termed "beaking." Beaking has been reported to precede AFF. The aims of the present study were to evaluate the incidence of latent beaking in patients with autoimmune diseases taking BPs and glucocorticoids and to identify risk factors for beaking. METHODS: A total of 125 patients with autoimmune diseases who were taking BPs and glucocorticoids was included; 116 patients underwent X-rays and analysis of serum and urine bone metabolic markers annually for 2 years. Mean patient age was 54.5 years; there were 105 (90.5%) females and the mean duration of disease was 13.2 years. Focal lateral cortical thickening in femoral X-rays was defined as beaking. RESULTS: Beaking was detected in 15 femora of 10 patients (8.0%) at the time of recruitment. Over the 2-year observation period, the incidence of beaking increased to 21 femora of 12 patients (10.3%), and a complete AFF at the location of beaking occurred in one patient. Beaking was associated with a longer duration of BP treatment (6.1 ± 1.0 years vs. 5.0 ± 2.9 years, p = 0.01). Age 40-60 years, BP therapy ≥4 years, and diabetes mellitus were significantly associated with beaking. CONCLUSIONS: The incidence of beaking was high, and increased over 2 years, in patients with autoimmune diseases who were taking BPs and glucocorticoids. Regular femoral X-rays are strongly recommended to screen for beaking. Long-term BP/glucocorticoid use was a risk factor for beaking in patients with autoimmune diseases; BP drug holidays should be considered.
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Enfermedades Autoinmunes/tratamiento farmacológico , Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Fracturas por Estrés/inducido químicamente , Glucocorticoides/efectos adversos , Absorciometría de Fotón/métodos , Adulto , Anciano , Biomarcadores/metabolismo , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/uso terapéutico , Complicaciones de la Diabetes/diagnóstico por imagen , Complicaciones de la Diabetes/metabolismo , Difosfonatos/administración & dosificación , Difosfonatos/uso terapéutico , Esquema de Medicación , Femenino , Fracturas del Fémur/inducido químicamente , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/metabolismo , Fracturas por Estrés/diagnóstico por imagen , Fracturas por Estrés/metabolismo , Glucocorticoides/administración & dosificación , Glucocorticoides/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Factores de RiesgoRESUMEN
In the peripheral blood leukocytes (PBLs) from the carriers of the human T-lymphotropic virus type-1 (HTLV-1) or the patients with adult T-cell leukemia (ATL), nuclear factor kappaB (NF-κB)-mediated antiapoptotic signals are constitutively activated primarily by the HTLV-1-encoded oncoprotein Tax. Tax interacts with the I κB kinase regulatory subunit NEMO (NF-κB essential modulator) to activate NF-κB, and this interaction is maintained in part by a molecular chaperone, heat-shock protein 90 (HSP90), and its co-chaperone cell division cycle 37 (CDC37). The antibiotic geldanamycin (GA) inhibits HSP90's ATP binding for its proper interaction with client proteins. Administration of a novel water-soluble and less toxic GA derivative, 17-dimethylaminoethylamino-17-demethoxygeldanamycin hydrochloride (17-DMAG), to Tax-expressing ATL-transformed cell lines, C8166 and MT4, induced significant degradation of Tax. 17-DMAG also facilitated growth arrest and cellular apoptosis to C8166 and MT4 and other ATL cell lines, although this treatment has no apparent effects on normal PBLs. 17-DMAG also downregulated Tax-mediated intracellular signals including the activation of NF-κB, activator protein 1 or HTLV-1 long terminal repeat in Tax-transfected HEK293 cells. Oral administration of 17-DMAG to ATL model mice xenografted with lymphomatous transgenic Lck-Tax (Lck proximal promoter-driven Tax transgene) cells or HTLV-1-producing tumor cells dramatically attenuated aggressive infiltration into multiple organs, inhibited de novo viral production and improved survival period. These observations identified 17-DMAG as a promising candidate for the prevention of ATL progression.
RESUMEN
Human T-cell leukemia virus type I (HTLV-I) can infect a variety of cell types, so the cause of T-cell-specific oncogenesis remains to be elucidated. The trans-activator protein Tax of HTLV-I can promote cell-cycle progression in resting T cells along with induction of cyclin D2 and cyclin-dependent kinase (cdk6) gene expression. Here, we found that Tax cannot induce cell-cycle progression in resting fibroblasts and analysed the molecular basis of the cell-type specificity. Tax activated cyclin D2 and cdk6 promoters in T cells, but not in fibroblasts, depending on its ability to activate the transcription factor nuclear factor (NF)-kappaB. Expression of cyclin D2 and CDK6 activated the transcription factor E2F, which is essential for cell-cycle progression, in both T cells and fibroblasts. Short-hairpin RNA (shRNA)-mediated inhibition of cyclin D2 and CDK6 induction suppressed Tax-induced activation of E2F in T cells. Finally, shRNA-mediated downregulation of NF-kappaB p65 or p100 expression reduced Tax-induced activation of cyclin D2 and/or cdk6 promoters and cell-cycle progression in T cells. These results indicate that Tax-induced cell-cycle progression in T cells is mediated, at least in part, through cell-type-specific activation of the cyclin D2 and cdk6 genes through NF-kappaB and may be important for the cell-type-specific oncogenesis.
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Ciclo Celular , Ciclina D2/genética , Quinasa 6 Dependiente de la Ciclina/genética , Productos del Gen tax/fisiología , FN-kappa B/fisiología , Animales , Línea Celular , Factores de Transcripción E2F/metabolismo , Regulación de la Expresión Génica , Humanos , Regiones Promotoras Genéticas , RatasRESUMEN
We established a human immunodeficiency virus type 1 (HIV-1) envelope (Env)-mediated membrane fusion assay and examined the small-molecule CCR5 antagonist TAK-779 and its derivatives for their inhibitory effects on HIV-1 Env-mediated membrane fusion and viral replication. The membrane fusion assay is based on HIV-1 long terminal repeat-directed beta-D-galactosidase reporter gene expression in CD4- and CCR5-expressed HeLa (MAGI-CCR5) cells after cocultivation with effector 293T cells expressing HIV-1 Env. Inhibition of HIV-1 replication was also determined in MAGI-CCR5 cells infected with the corresponding cell-free HIV-1. TAK-779 effectively suppressed R5 HIV-1 (strain JR-FL) Env-mediated membrane fusion as well as viral replication. Its 50% inhibitory concentrations (IC(50)s) for membrane fusion and viral replication were 0.87 +/- 0.11 and 1.4 +/- 0.1 nM, respectively. These values corresponded well to the IC(50) for (125)I-RANTES (regulated on activation, T cell expressed, and secreted) binding to CCR5 (1.4 nM). The inhibitory effects of 18 TAK-779 derivatives on membrane fusion differed from one compound to another. However, there was a close correlation among their inhibitory effects on membrane fusion, viral replication, and RANTES binding. The correlation coefficient between their IC(50)s for membrane fusion and viral replication was 0.881. Furthermore, since this assay depends on Env expressed in the effector cells, it is also applicable to the evaluation of CXCR4 antagonists. These results indicate that the HIV-1 Env-mediated membrane fusion assay is a useful tool for the evaluation of entry inhibitors.
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Amidas/farmacología , Fármacos Anti-VIH/farmacología , Antagonistas de los Receptores CCR5 , VIH-1/efectos de los fármacos , Fusión de Membrana/efectos de los fármacos , Compuestos de Amonio Cuaternario/farmacología , Proteínas del Envoltorio Viral/fisiología , Replicación Viral/efectos de los fármacos , Quimiocina CCL5/metabolismo , Productos del Gen tat/biosíntesis , Células HeLa , Humanos , Linfocitos T/efectos de los fármacos , Linfocitos T/virología , Productos del Gen tat del Virus de la Inmunodeficiencia HumanaRESUMEN
The treatment of sepsis may require mechanical ventilation of the lungs and sedation. Because neutrophils are the most important effector cells for protecting against sepsis, and propofol and midazolam are the most widely used anesthetics for sedation, we studied the effects of these two anesthetics on the neutrophil function during sepsis. Sepsis was induced in rats by cecal ligation and puncture. At either 4 h or 24 h after cecal ligation and puncture, blood and peritoneal neutrophils were obtained, incubated with the test anesthetics, and the hydrogen peroxide (H(2)O(2)) production and CD11b/c expression were determined by flow cytometry. In both early (at 4 h) and late (at 24 h) sepsis, propofol and midazolam depressed H(2)O(2) production by blood and peritoneal neutrophils at clinical concentrations. Propofol caused more depression than midazolam (P < 0.005). In both early and late sepsis, the effect of the anesthetics on the up-regulation of the stimulation-induced CD11b/c expression on blood neutrophils was minimal at clinical concentrations. If these results ultimately become clinically relevant, midazolam may be preferable to propofol for sedation during sepsis.
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Anestésicos Intravenosos/farmacología , Peróxido de Hidrógeno/metabolismo , Integrina alfaXbeta2/biosíntesis , Antígeno de Macrófago-1/biosíntesis , Midazolam/farmacología , Neutrófilos/efectos de los fármacos , Propofol/farmacología , Sepsis/metabolismo , Animales , Masculino , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
To examine the involvement of transforming growth factor-beta(1 )(TGF-beta(1)) in intestinal anastomotic repair, we administered a TGF-beta(1)-neutralizing antibody to rats after operation, and then examined its influence on the healing process and interaction with other peptide growth factors. Thirty male Sprague-Dawley rats were subjected to primary anastomosis after transection of the small intestine (n = 30) and treated by intraperitoneal administration of IgG (n = 15) or the TGF-beta(1) neutralizing antibody (n = 15). Treatment with the antibody against TGF-beta(1) resulted in more definite mucosal growth and increased vascularity on day 5 after surgery. Augmented mRNA expression of epidermal growth factor and vascular endothelial growth factor, and an increased number of cells that expressed these peptides in granulation tissue were demonstrated by RT-PCR and immunohistochemical staining. Taken together it was indicated that TGF-beta(1) has negative effects on regeneration of the bowel wall mucosa and angiogenesis in the course of intestinal anastomotic wound healing.
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Anastomosis Quirúrgica , Intestinos/fisiopatología , Intestinos/cirugía , Regeneración/fisiología , Factor de Crecimiento Transformador beta/fisiología , Animales , Anticuerpos/inmunología , Vasos Sanguíneos/fisiopatología , Factores de Crecimiento Endotelial/genética , Factor de Crecimiento Epidérmico/genética , Expresión Génica/fisiología , Mucosa Intestinal/fisiopatología , Intestinos/irrigación sanguínea , Linfocinas/genética , Masculino , Ratas , Ratas Sprague-Dawley , Factor de Crecimiento Transformador beta/inmunología , Factor de Crecimiento Transformador beta1 , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial VascularRESUMEN
Transforming growth factor beta (TGF-beta) initiates signaling through heteromeric complexes of transmembrane type I and type II serine/threonine kinase receptors. Activated TGF-beta type I receptor phosphorylates receptor-regulated Smads (2 and 3). Antagonistic Smad 7 forms stable association with the activated TGF-beta type I receptor, blocking phosphorylation of receptor-regulated Smads. On the other hand, elevated serum concentration of TGF-beta along with resistance to its growth-inhibitory effect is commonly observed in human hepatocellular carcinoma (HCC) patients. In this study, we investigated the mechanisms of resistance to tumor-derived TGF-beta in human HCC and hepatoblastoma-derived cell lines, focusing on the roles of receptor-regulated Smads and antagonistic Smad 7. HuH-7 and HepG2 cells showed poor response to TGF-beta-mediated growth inhibition. Because neutralization of TGF-beta in the medium or blockage of signal transduction pathway by inductions of dominant negative Smad 2/3 resulted in a stimulation of cell growth, tumor-derived TGF-beta signal acts on cell growth negatively. However, Smad 7 induced by TGF-beta negatively regulated Smad 2 action and rendered most Smad 2 proteins in the cytoplasm. Taken together, these results indicate that endogenous TGF-beta-mediated induction of Smad 7 results in a higher "threshold" for the antiproliferative signals mediated by receptor-regulated Smads, and can be involved in reduced responsiveness to the cytokine in some human HCC cells.
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Carcinoma Hepatocelular/patología , Proteínas de Ciclo Celular , Proteínas de Unión al ADN/fisiología , Neoplasias Hepáticas/patología , Transactivadores/fisiología , Factor de Crecimiento Transformador beta/fisiología , Proteínas Supresoras de Tumor , Inhibidor p15 de las Quinasas Dependientes de la Ciclina , Humanos , Fosforilación , Inhibidor 1 de Activador Plasminogénico/genética , ARN Mensajero/análisis , Receptor IGF Tipo 2/análisis , Proteína Smad2 , Proteína smad3 , Proteína smad7 , Factores de Transcripción/fisiología , Factor de Crecimiento Transformador beta/genética , Células Tumorales CultivadasRESUMEN
BACKGROUND: A hallmark of HIV-1 gene expression is that unspliced genomic RNA, which also acts as mRNA for the expression of Gag/Pol, is exported to the cytoplasm. Rev directs this transport through the nuclear export signal (NES). RESULTS: Fluorescence in situ hybridization and immunocytochemistry demonstrated that gag mRNA, Rev, and its NES receptor, CRM1, and RanGTPase formed nuclear tracks which were congruent with underlying beta-actin bundles. Actin bundle formation was confirmed electron-microscopically. These bundles were observed upon Rev-containing gag RNP formation. The loss of bundles was associated with the nuclear retention of gag mRNA. Reverse transcription-polymerase chain reaction analysis of both cytoplasmic and nuclear gag mRNAs demonstrated that disruption of nuclear actin filament formation by latrunculin-B (LAT-B), an F-actin depolymerizing compound, resulted in the dose-dependent inhibition of gag mRNA export. The differential subtyping of the mRNA-positive cells confirmed morphologically the effect of LAT-B treatment. The export inhibition was specific to gag mRNA and export of fully spliced HIV-1 tat/rev mRNAs as well as cellular GAPDH mRNA was not affected by the compound. CONCLUSIONS: Nuclear beta-actin bundles are suggested to be functionally involved in the Rev-dependent nucleocytoplasmic transport of intron-containing HIV-1 gag mRNA.
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Actinas/metabolismo , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Productos del Gen gag/metabolismo , Productos del Gen rev/metabolismo , Carioferinas , ARN Mensajero/metabolismo , Receptores Citoplasmáticos y Nucleares , Tiazoles/farmacología , Transporte Biológico/efectos de los fármacos , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Núcleo Celular/química , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , ADN Recombinante/genética , ADN Recombinante/metabolismo , Relación Dosis-Respuesta a Droga , Técnica del Anticuerpo Fluorescente Indirecta , GTP Fosfohidrolasas/metabolismo , Productos del Gen gag/genética , Productos del Gen rev/genética , Células HeLa , Humanos , Hibridación Fluorescente in Situ , Intrones , Microscopía Inmunoelectrónica , Plásmidos , Unión Proteica , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Precursores del ARN/genética , Precursores del ARN/metabolismo , ARN Mensajero/genética , ARN Viral/genética , ARN Viral/metabolismo , Ribonucleoproteínas/metabolismo , Tiazolidinas , Proteína de Unión al GTP ran/metabolismo , Proteína Exportina 1RESUMEN
Polyomavirus JC (JCV) causes the human demyelinating disease, progressive multifocal leukoencephalopathy (PML). The recent demonstration of cases of PML in association with human T-lymphotropic virus type I (HTLV-I) infection prompted us to examine whether the HTLV-I-encoded regulatory protein Tax activates JCV transcription. By employing a dual luciferase assay, we initially found that the expression of Tax activated the transcriptional potential of both early and late promoters of JCV in human neuronal but not in non-neuronal cells. We subsequently analyzed the mechanism of Tax-induced activation of the JCV promoter in neuronal cells with the following results: 1) the JCV promoter that lacks the NF-kappaB-binding motif could not be activated by Tax; 2) the overexpression of IkappaBalpha abolished Tax-induced transcriptional activation of the JCV promoter; 3) a Tax mutant (M22) lacking the potential for activation via the NF-kappaB pathway did not activate the JCV promoter. Furthermore, Tax enhances the gene expression of JCV T antigen and VP1. We examined mechanisms of the cell-specific activation of the JCV promoter by Tax. Electrophoretic mobility shift assay demonstrated the presence of Tax-bound protein(s) that were specifically present in non-neuronal cells. This study is the first demonstration of the activation of JCV promoter by HTLV-I Tax in an NF-kappaB-dependent manner.
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Productos del Gen tax/metabolismo , Virus JC/genética , Neuronas/metabolismo , Activación Transcripcional , Secuencia de Bases , Cartilla de ADN , ADN Viral/genética , Humanos , Regiones Promotoras Genéticas , Eliminación de Secuencia , Células Tumorales CultivadasRESUMEN
Phorbol 12-myristate 13-acetate (PMA) induces differentiation of human leukemic HL-60 cells into cells with macrophage-like characteristics and enhances the susceptibility of HL-60 cells to the Helicobacter pylori VacA toxin (de Bernard, M., Moschioni., M., Papini, E., Telford, J. L., Rappuoli, R., and Montecucco, C. (1998) FEBS Lett. 436, 218-222). We examined the mechanism by which HL-60 cells acquire sensitivity to VacA, in particular, looking for expression of RPTPbeta, a VacA-binding protein postulated to be the VacA receptor (Yahiro, K., Niidome, T., Kimura, M., Hatakeyama, T., Aoyagi, H., Kurazono, H., Imagawa, K., Wada, A., Moss, J., and Hirayama, T. (1999) J. Biol. Chem. 274, 36693-36699). PMA induced expression of RPTPbeta mRNA and protein as determined by RNase protection assay and indirect immunofluorescence studies, respectively. Vitamin D(3) and interferon-gamma, which stimulate differentiation of HL-60 cells into monocyte-like cells, also induced VacA sensitivity and expression of RPTPbeta mRNA, whereas 1. 2% Me(2)SO and retinoic acid, which stimulated the maturation of HL-60 into granulocyte-like cells, did not. RPTPbeta antisense oligonucleotide inhibited induction of VacA sensitivity and expression of RPTPbeta. Double immunostaining studies also indicated that newly expressed RPTPbeta colocalized with VacA in PMA-treated HL-60 cells. In agreement with these data, BHK-21 cells, which are insensitive to VacA, when transfected with the RPTPbeta cDNA, acquired VacA sensitivity. All data are consistent with the conclusion that acquisition of VacA sensitivity by PMA-treated HL-60 cells results from induction of RPTPbeta, a protein that functions as the VacA receptor.
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Proteínas Bacterianas/toxicidad , Diferenciación Celular/fisiología , Regulación de la Expresión Génica , Helicobacter pylori , Proteínas del Tejido Nervioso/genética , Proteínas Tirosina Fosfatasas/genética , Vacuolas/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colecalciferol/farmacología , Células HL-60 , Humanos , Interferón gamma/farmacología , Cinética , Oligonucleótidos Antisentido/farmacología , Proteínas Tirosina Fosfatasas Clase 5 Similares a Receptores , Receptores de Superficie Celular/genética , Acetato de Tetradecanoilforbol/farmacología , Tionucleótidos/farmacología , Transcripción Genética , Tretinoina/farmacologíaRESUMEN
The serum concentration of transforming growth factor beta (TGF-beta) is elevated as tumors progress in hepatocellular carcinoma (HCC) patients. In this study, we examined whether modulation of tumor-derived TGF-beta signal transduction contributes to malignant progression. We investigated the production of TGF-beta1, the biological effects of TGF-beta and neutralizing antibody on HCC cells, activation of Smad 2, Smad 3, and Smad 4, induction of antagonistic Smads (Smad 6 and Smad 7), and promoter activities of two target genes, plasminogen activator inhibitor type 1 (PAI-1) and p15INK4B. In human cell lines HCC-M and HCC-T, TGF-beta accelerates their proliferation. Smad 2 was activated constitutively by an autocrine mechanism, because in the absence of exogenous TGF-beta, a high level of Smad 2 phosphorylation, induction of PAI-1 transcripts, and nuclear localization of Smad 2 were observed. This constitutive activation of Smad 2 was, at least in part, attributable to the lack of induction of antagonistic Smads by TGF-beta. However, Smads activated by tumor-derived TGF-beta constantly suppressed p151NK4B expression. In addition, 3 of 10 human HCC tissues showed nuclear localization of Smad 2 and low mRNA levels of p15INK4B and antagonistic Smads but a high level of PAI-1. Our observations suggest that this constant suppression of the p15INK4B gene could be involved in the malignant progression of HCC.
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Comunicación Autocrina , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Carcinoma Hepatocelular/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Genes Supresores de Tumor , Humanos , Neoplasias Hepáticas/genética , Factor de Crecimiento Transformador beta/genética , Células Tumorales CultivadasRESUMEN
Transforming growth factor-beta (TGF-beta)-activated kinase 1 (TAK1), a member of the mitogen-activated protein kinase kinase kinase family, is suggested to be involved in TGF-beta-induced gene expression, but the signaling mechanism from TAK1 to the nucleus remains largely undefined. We have found that p38 mitogen-activated protein kinase, and its direct activator MKK6 are rapidly activated in response to TGF-beta. Expression of dominant negative MKK6 or dominant negative TAK1 inhibited the TGF-beta-induced transcriptional activation as well as the p38 activation. Constitutive activation of the p38 pathway in the absence of TGF-beta induced the transcriptional activation, which was enhanced synergistically by coexpression of Smad2 and Smad4 and was inhibited by expression of the C-terminal truncated, dominant negative Smad4. Furthermore, we have found that activating transcription factor-2 (ATF-2), which is known as a nuclear target of p38, becomes phosphorylated in the N-terminal activation domain in response to TGF-beta, that ATF-2 forms a complex with Smad4, and that the complex formation is enhanced by TGF-beta. In addition, expression of a nonphosphorylatable form of ATF-2 inhibited the TGF-beta-induced transcriptional activation. These results show that the p38 pathway is activated by TGF-beta and is involved in the TGF-beta-induced transcriptional activation by regulating the Smad-mediated pathway.
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Proteínas Quinasas Dependientes de Calcio-Calmodulina/fisiología , Regulación de la Expresión Génica , Quinasas Quinasa Quinasa PAM , Proteínas Quinasas Activadas por Mitógenos , Factor de Crecimiento Transformador beta/fisiología , Factor de Transcripción Activador 2 , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Células Cultivadas , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteínas de Unión al ADN/metabolismo , Genes Supresores de Tumor , Leucina Zippers , MAP Quinasa Quinasa 6 , Proteínas Quinasas/metabolismo , Transducción de Señal , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
Histiocytoid breast carcinoma (HBC) is a rare variant of breast carcinoma and often causes a diagnostic dilemma because of its histological similarities to some types of breast cancer and benign lesions. To elucidate the incidence of HBC and its biological properties, histological specimens from 1010 breast cancer patients treated at Yokohama Minami Kyosai Hospital between 1972 and 1996 were reviewed. Three cases of pure HBC and three cases of combined HBC (two with pleomorphic lobular carcinoma and one with apocrine ductal carcinoma) were found, yielding an incidence of 0.3% for each. Two of the three pure HBC cases contained foci of in situ lobular carcinoma. Targetoid and Indian file invasive patterns, the features characteristic of lobular carcinoma, were present in all three pure HBC cases and in two of the three combined HBC with pleomorphic lobular carcinoma. These results, together with those of previous studies, suggested that the majority of HBC are of lobular origin, although the apocrine ductal origin is also possible in a small number of HBC. Diastase-resistant periodic acid-Schiff-positive granules and granular immunoreactivities for gross cystic disease fluid protein-15 (GCDFP-15) were characteristic of the histiocytoid tumor cells in both the pure and combined HBC, suggesting the apocrine differentiation of tumor cells. All three pure HBC cases were in stage 1 and were free of the disease for up to 5 years and 1 month after the lumpectomy. Thus, the prognosis of HBC appears to be dependent on the stage of the disease and may not always be poor, as indicated by the original report mentioning a preferential eyelid metastasis.
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Apolipoproteínas , Neoplasias de la Mama/patología , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/patología , Carcinoma Lobular/patología , Glicoproteínas , Histiocitos/patología , Proteínas de Transporte de Membrana , Adulto , Anciano , Apolipoproteínas D , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Carcinoma in Situ/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Proteínas Portadoras/metabolismo , Diagnóstico Diferencial , Femenino , Histiocitos/metabolismo , Humanos , Técnicas para Inmunoenzimas , Persona de Mediana EdadRESUMEN
A model of herpes simplex virus type 1 (HSV-1) infection was developed in rats to study systemic immune responses elicited by intravitreous inoculation of the virus. HSV-1 inoculation led to distinct granulocyte-macrophage colony-stimulating factor (GM-CSF)-producing memory T cells, which did not develop in rats inoculated with either HSV-1 intraperitoneally or inactivated HSV-1 intravitreously. On subsequent intraperitoneal viral boosting, systemic GM-CSF production was elicited as a secondary immune response that caused neutroeosinophilia. To examine the role of GM-CSF in anti-herpetic immunity, cytokine-producing and -nonproducing rats were intravitreously challenged with HSV-1, which causes lethal encephalitis. Only intravitreously primed rats were protected upon production of GM-CSF. Furthermore, pretreatment with recombinant GM-CSF protected unimmunized rats against the encephalitis. It is thus strongly suggested that the production of GM-CSF leads to anti-HSV-1 immunity against the transneuronal spread of challenged HSV-1 within the visual system.
Asunto(s)
Encefalitis Viral/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Herpes Simple/inmunología , Herpesvirus Humano 1/inmunología , Queratitis Herpética/inmunología , Linfocitos T/inmunología , Traslado Adoptivo , Animales , Anticuerpos Antivirales/biosíntesis , Anticuerpos Antivirales/inmunología , Chlorocebus aethiops , Encefalitis Viral/prevención & control , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/sangre , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Granulocitos/inmunología , Herpes Simple/prevención & control , Humanos , Memoria Inmunológica , Queratitis Herpética/prevención & control , Leucocitos/inmunología , ARN Mensajero , Ratas , Ratas Endogámicas F344 , Ratas Desnudas , Proteínas Recombinantes/farmacología , Bazo/inmunología , Células VeroRESUMEN
A survey of acute myocardial infarctions (AMI) that occurred from October 1990 through September 1993 in Obihiro City, Hokkaido, was conducted. A total of 114 new cases of AMI was registered over the 3-year period. The incidence rate of AMI was 33.4 cases per 100,000 men per year and 137 cases per 100,000 women per year (total, 23.2 cases). The mean age at which AMI occurred was 11 years higher in women (71.1 +/- 9.4 years) than in men (60.0 +/- 11.8 years). In men, AMI was most common during the eighth decade of life, while in women the incidence of AMI increased after menopause. The ratio of cases of AMI to cases of stroke in the same period was 1:4.5. These results did not differ from the results of other surveys done over the same period in seven other area of Japan. To study risk factors for myocardial infarction, the data were grouped according to the results of medical examinations. Hypertension, diabetes, obesity and smoking were common among people with AMI. The incidence rate of hypercholesterolemia did not differ between those with AMI and those without, and only a relatively small number of people with AMI drank alcohol. Past reports have pointed out changes in the 'structure' of cardiovascular disease in Japan, which have accompanied changes in diet and lifestyle. This study has shows that aging hypertension, diabetes, obesity, and smoking are risk factors for myocardial infarction. Proper management, including early detection of these factors, will help to prevent of ischemic heart disease in Japan.
Asunto(s)
Infarto del Miocardio/epidemiología , Adulto , Factores de Edad , Anciano , Trastornos Cerebrovasculares/epidemiología , Femenino , Humanos , Incidencia , Japón/epidemiología , Estilo de Vida , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Sistema de Registros , Factores de RiesgoRESUMEN
The prevalence of glucose intolerance was surveyed in 8,063 people over 30 years old from the general population of Japan. The data used in the analysis were from the Fourth National Circulatory Disorders Basic Survey, which was conducted in 1990. Survey items included history of diabetes mellitus, body mass index (BMI) and daily life activity. Blood and urine were also examined, and the blood glucose levels, presence or absence of sugar in urine, and levels of glycohemoglobin (HbA1c) were determined. Glucose intolerance was identified from the blood glucose level, HbA1c level and history of diabetes mellitus. The frequency of glucose intolerance was 8.6% in all subjects (11.9% in men and 6.3% in women). The frequency was higher in older people: 1.7 times higher in men over 65 years old and 2.5 times higher in women over 65 years old. Among people over 40 years old, glucose intolerance was significantly more prevalent in men than in women. It was also significantly more prevalent in men living in big cities than in men living in rural areas. Among obese male subjects and men with a low level of activity in daily life, the frequency of glucose intolerance was higher than in normal male subjects. The level of activity in daily life tended to be lower for people living in big cities than for those in rural areas. The results suggest that the prevalence of glucose intolerance depends on the environment in which people live. The results also indicate that raising the level of activities in daily life might help prevent diabetes mellitus.