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1.
Diabet Med ; 34(12): 1795-1799, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29044699

RESUMEN

BACKGROUND: Diabetic striatopathy, one of the complications of diabetes mellitus, is characterized by involuntary movements, including hemichorea and hemiballismus, and the presence of hyperintense lesions on T1-weighted magnetic resonance imaging of the striatum. CASE REPORT: We present a case of diabetic striatopathy manifesting as severe consciousness disturbance without chorea or ballismus. A 58-year-old man was admitted to our hospital in a state of unconsciousness. He was diagnosed with diabetic striatopathy as a result of extremely elevated blood glucose levels and typical magnetic resonance imaging findings in the left striatum, although involuntary movements were absent. He was treated with insulin, and his glucose levels were well maintained. His neuropsychiatric symptoms recovered, rather slowly but completely, after ~20 days. CONCLUSION: This case indicates the diversity of striatal dysfunction induced by hyperglycaemia. For good prognosis of diabetic striatopathy, prompt diagnosis and appropriate treatments are important. Physicians should be aware that this disease can cause various neurological and psychiatric symptoms other than chorea or ballismus.


Asunto(s)
Enfermedades del Sistema Nervioso Central/diagnóstico , Cuerpo Estriado/patología , Complicaciones de la Diabetes/diagnóstico , Inconsciencia/diagnóstico , Enfermedades del Sistema Nervioso Central/etiología , Complicaciones de la Diabetes/patología , Diagnóstico Diferencial , Discinesias , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Inconsciencia/etiología
2.
Br J Cancer ; 103(6): 877-84, 2010 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-20700123

RESUMEN

BACKGROUND: Hypopharyngeal squamous cell carcinoma (HSCC) is an aggressive malignancy with one of the worst prognoses among all head and neck cancers. Greater understanding of the pertinent molecular oncogenic pathways could help improve diagnosis, therapy, and prevention of this disease. The aim of this study was to identify tumour-suppressive microRNAs (miRNAs), based on miRNA expression signatures from clinical HSCC specimens, and to predict their biological target genes. METHODS: Expression levels of 365 human mature miRNAs from 10 HSCC clinical samples were screened using stem-loop real-time quantitative PCR. Downregulated miRNAs were used in cell proliferation assays to identify a tumour-suppressive miRNA. Genome-wide gene expression analyses were then performed to identify the target genes of the tumour-suppressive miRNA. RESULTS: Expression analysis identified 11 upregulated and 31 downregulated miRNAs. Gain-of-function analysis of the downregulated miRNAs revealed that miR-489 inhibited cell growth in all head and neck cancer cell lines examined. The gene PTPN11 coding for a cytoplasmic protein tyrosine phosphatase containing two Src Homology 2 domains was identified as a miR-489-targeted gene. Knockdown of PTPN11 resulted in the inhibition of cell proliferation in head and neck SCC cells. CONCLUSION: Identification of the tumour-suppressive miRNA miR-489 and its target, PTPN11, might provide new insights into the underlying molecular mechanisms of HSCC.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias Hipofaríngeas/genética , MicroARNs/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Anciano , Línea Celular Tumoral , Regulación hacia Abajo , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Interferente Pequeño , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
3.
J Investig Allergol Clin Immunol ; 19(3): 195-203, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19610262

RESUMEN

BACKGROUND: In recent years, many countries have experienced an increase in the prevalence of allergic rhinitis. No effective approach is currently available to prevent the onset of symptoms in allergic individuals. Pranlukast, a leukotriene receptor antagonist with a good safety and efficacy record for the management of allergic inflammation, may be appropriate for early intervention in the management of pollinosis. OBJECTIVE: To investigate the efficacy of pranlukast as an early intervention in the control of cedar pollinosis. METHODS: In a double-blind comparative study, pranlukast (n = 102) or placebo (n = 91) was administered to cedar pollinosis patients immediately before the start of the dispersion season and continued for 4 weeks. Subsequently, pranlukast was administered to all patients for 2 weeks until the end of the cedar pollen dispersion season (mid-March). All patients were carefully monitored for severity of nasal symptoms, symptom scores, medication scores, symptom-medication scores, and quality of life (QOL). RESULTS: Compared with placebo, therapy with pranlukast before and during the dispersion of cedar pollen in these patients significantly improved nasal symptoms (paroxysmal sneezing, rhinorrhea, and nasal congestion), symptom scores, and symptom-medication scores. The drug also significantly reduced deterioration of QOL, and improved nasal symptoms and QOL throughout the dispersion period. CONCLUSION: Administering pranlukast immediately before the beginning of cedar pollen dispersion is effective in reducing symptoms of allergic rhinitis throughout the dispersion period.


Asunto(s)
Cromonas/uso terapéutico , Cryptomeria/inmunología , Antagonistas de Leucotrieno/uso terapéutico , Polen/inmunología , Rinitis Alérgica Estacional/tratamiento farmacológico , Adulto , Cromonas/administración & dosificación , Cromonas/efectos adversos , Método Doble Ciego , Femenino , Humanos , Antagonistas de Leucotrieno/administración & dosificación , Antagonistas de Leucotrieno/efectos adversos , Masculino , Persona de Mediana Edad , Calidad de Vida , Rinitis Alérgica Estacional/inmunología
4.
Clin Exp Allergy ; 38(3): 405-12, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18070160

RESUMEN

BACKGROUND: Allergic rhinitis (AR) is a typical type I allergic disease that occurs through the induction of allergen-specific effector T cells. Once established, new effector T cells derive mostly from memory T cells that are capable of surviving for extended periods, although the mechanisms by which these memory functions are maintained have not yet been clarified. In particular, the exact life-span of memory T cells is still not well understood. OBJECTIVE: Pollinosis patients seemed to be suitable subjects to investigate because such patients are exposed to antigens strongly for only a limited period once a year. We compared the seasonal changes in memory T-helper type 2 (Th2) between pollinosis and perennial allergic subjects. METHODS: The clone sizes of the Japanese cedar pollen-specific memory Th cells were measured by an ELISPOT assay using specific peptides from the patients with cedar pollinosis, and the seasonal changes were noted. This study was performed for 2 years. The cedar-specific IgE levels in the peripheral blood were also studied. Mite allergy patients were also enrolled in the study. RESULTS: The Japanese cedar-specific IL-4-producing Th2 cells were detected in all patients examined, although the number of cells was low. These Th memory cells increased during the pollen season and decreased during the off-season. However, more than 60% of the cedar-specific memory Th2 cells survived up to 8 months after the pollen season. The cedar-specific IgE levels exhibited changes similar to the cedar-specific Th cells. On the other hand, there was no drifting of Th memory clone size with the mite allergics, and the IgE levels also did not change. CONCLUSIONS: While pollen-specific Th cells decreased after pollen exposure, their memory functions continued. Memory clone size maintenance therefore requires repetitive antigen irritation.


Asunto(s)
Cryptomeria/inmunología , Rinitis Alérgica Estacional/inmunología , Rinitis Alérgica Estacional/patología , Estaciones del Año , Células Th2/inmunología , Células Th2/patología , Adulto , Animales , Recuento de Linfocito CD4 , Células Clonales/patología , Epítopos , Femenino , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Memoria Inmunológica , Interleucina-4/biosíntesis , Masculino , Persona de Mediana Edad , Polen/inmunología , Pyroglyphidae/inmunología , Rinitis Alérgica Perenne/inmunología , Rinitis Alérgica Perenne/patología , Células Th2/metabolismo
5.
Cancer Res ; 59(12): 2950-6, 1999 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-10383160

RESUMEN

Whereas transplantable tumors can be readily cured with immunotherapeutic approaches, similar therapies in cancer patients have been less effective. This difference may be explained by an immunosuppression resulting from the presence of a slowly growing primary tumor in the patient, whereas the immune system in a mouse with a rapidly proliferating transplantable tumor would be less affected. As a more appropriate model to the immune dysfunction in patients, slowly progressing primary tumors were induced by the carcinogen methylcholanthrene (MC) in mice. Their ability to induce immunosuppression in T cells and natural killer (NK) cells was compared to that of rapidly growing transplanted MC-induced tumors. The results demonstrate that mice bearing primary MC tumors had significantly diminished T-cell and NK-cell functions, impaired capacity to produce Th1 cytokines, and markedly reduced levels of the signal-transducing zeta chain in T cells and NK cells, similar to that described in cancer patients. Moreover, a substantial number of CD8+ T cells in mice with large primary MC tumors were undergoing apoptosis, correlating with alterations in CD4/CD8 ratios. In contrast, T cells and NK cells from mice bearing rapidly growing transplanted tumors were only marginally affected. These findings could explain the apparent discrepancy between the consistent findings of a diminished immune response and alterations in signal transduction in cancer patients as compared to the less reproducible observations in murine transplantable tumors. In addition, they could explain the differences in the high efficacy of immunotherapy in mice with transplantable tumors and the low therapeutic results in cancer patients.


Asunto(s)
Apoptosis , Tolerancia Inmunológica , Células Asesinas Naturales/inmunología , Sarcoma Experimental/inmunología , Transducción de Señal , Linfocitos T/inmunología , Animales , Complejo CD3/inmunología , Recuento de Linfocito CD4 , Linfocitos T CD8-positivos/efectos de los fármacos , Carcinógenos , Citocinas/biosíntesis , Citocinas/inmunología , Citotoxicidad Inmunológica , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/patología , Metilcolantreno , Ratones , Trasplante de Neoplasias , Receptores de Antígenos de Linfocitos T gamma-delta/biosíntesis , Sarcoma Experimental/etiología , Sarcoma Experimental/patología , Bazo/efectos de los fármacos , Bazo/inmunología , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/patología , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Células TH1/efectos de los fármacos , Células TH1/inmunología
6.
Cancer Gene Ther ; 23(8): 278-83, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27468808

RESUMEN

Reduced expression in immortalized cells (REIC)/dickkopf-3 (Dkk-3), a tumor suppressor gene, is downregulated in various cancers. We previously reported the tumor-inhibitory effects of the REIC/Dkk-3 gene, delivered by a conventional adenoviral vector (Ad-CAG-REIC) in pancreatic cancer. Here, we developed an Ad-REIC vector with a novel gene expression system, termed the super gene expression (SGE) system, and assessed its therapeutic effects relative to those of Ad-CAG-REIC in pancreatic cancer cells. Human pancreatic cancer cell lines ASPC1 and MIAPaCa2 were used. REIC/Dkk-3 expression was assessed by western blot analysis. Relative cell viability and apoptotic effects were examined in vitro. The anti-tumor effects of Ad-REIC treatment were assessed in the mouse xenograft model. Compared with Ad-CAG-REIC, Ad-SGE-REIC elicited a significant increase in REIC protein expression in the cells studied. Relative to Ad-CAG-REIC, Ad-SGE-REIC reduced cell viability and induced apoptosis in the ASPC1 and MIAPaCa2 cell lines in vitro, and achieved superior tumor growth inhibition in the mouse xenograft model. Compared with conventional Ad-REIC agents, Ad-SGE-REIC provided enhanced inhibitory effects against tumor growth. Our results indicate that Ad-SGE-REIC is an innovative therapeutic tool for pancreatic cancer.


Asunto(s)
Adenoviridae/genética , Terapia Genética , Vectores Genéticos/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Neoplasias Pancreáticas/genética , Proteínas Adaptadoras Transductoras de Señales , Animales , Apoptosis/genética , Línea Celular Tumoral , Supervivencia Celular/genética , Quimiocinas , Modelos Animales de Enfermedad , Expresión Génica , Orden Génico , Vectores Genéticos/administración & dosificación , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Ratones , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/terapia , Transducción de Señal , Carga Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Cardiovasc Res ; 28(4): 480-4, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8181034

RESUMEN

OBJECTIVE: The aim was to elucidate the functional role of the sarcoplasmic reticulum in myogenic contraction. METHODS: Small arteries which perfuse the rat gracilis muscle were isolated and cannulated. The inner diameter was measured under no flow condition. Myogenic contraction was induced by increasing transmural pressure from 40 to 100 mm Hg. The diameter transient and the steady state internal diameter were analysed at 40 (ID40) and 100 mm Hg (ID100) of lumen pressure. RESULTS: In control, the vessels dilated immediately after the pressure change, and then constricted over approximately 4 min (the diameter decay). ID40 and ID100 were 120(SEM 16) and 108(12) microns (n = 6, p < 0.05), respectively. Ryanodine (10(-5) M) decreased ID40 to 82(8) microns. The relative rate of the diameter decay in the first 1 min was lower in the ryanodine treated vessels than in control, at 43(1)% v 74(7)%, n = 6 (p < 0.05). While KCl constriction was similar to that of ryanodine, the diameter decay was identical to that of control. Thus a decrease in baseline diameter was not of itself the cause of the depressed rate of diameter decay in the ryanodine treated vessels. Nisoldipine (10(-6) M) abolished myogenic contraction. CONCLUSIONS: Ryanodine sensitive sarcoplasmic reticular function is probably involved in the mechanism for developing the myogenic response in rat skeletal muscle small arteries.


Asunto(s)
Contracción Muscular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Rianodina/farmacología , Retículo Sarcoplasmático/fisiología , Animales , Arterias , Cafeína/farmacología , Técnicas de Cultivo , Músculo Liso Vascular/efectos de los fármacos , Nisoldipino/farmacología , Ratas , Ratas Wistar , Retículo Sarcoplasmático/efectos de los fármacos
8.
Thromb Haemost ; 85(2): 356-61, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11246560

RESUMEN

Induction of procoagulant factors in malignant cells is considered to be the major cause of coagulation disorders in cancer. Thrombomodulin (TM), a negative regulator of coagulation was also found to be expressed in cancer cells. We report here evidence for another anticoagulant, the endothelial cell protein C receptor (EPCR), in cancer cells. EPCR was detected in several cell lines derived from various types of cancer. Significant levels of protein C (PC) activation were detected only with cell lines expressed both EPCR and TM. Anti-EPCR monoclonal antibodies (mAbs) specifically inhibited the activation. Thus, EPCR function appears to be important for PC activation by cancer cells. In addition, we detected EPCR expression in tumor cells from breast cancer patients, with an extremely high frequency. EPCR function may contribute to progression or pathogenesis of some types of cancer, and may explain the complexity of coagulopathy in cancer patients.


Asunto(s)
Factores de Coagulación Sanguínea , Receptores de Superficie Celular/metabolismo , Células Tumorales Cultivadas/metabolismo , Anticoagulantes/metabolismo , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patología , Activación Enzimática/efectos de los fármacos , Femenino , Citometría de Flujo , Glioblastoma/metabolismo , Glicosilación , Humanos , Inmunohistoquímica , Leucemia/metabolismo , Leucemia/patología , Masculino , Proteínas de Neoplasias/metabolismo , Proteína C/efectos de los fármacos , Proteína C/metabolismo , Receptores de Superficie Celular/fisiología , Trombomodulina/metabolismo , Células Tumorales Cultivadas/química
9.
Brain Res ; 510(1): 26-32, 1990 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-2322844

RESUMEN

The effects of intrathecal administration of prostaglandins on pain responses in conscious mice were evaluated by using hot plate and acetic acid writhing tests. Prostaglandin D2 (0.5-3 ng/mouse) had a hyperalgesic action on the response to a hot plate during a 3-60 min period after injection. Prostaglandin E2 showed a hyperalgesic effect at doses of 1 pg to 10 ng/mouse, but the effect lasted shorter (3-30 min) than that of prostaglandin D2. Similar results were obtained by acetic acid writhing tests. The hyperalgesic effect of prostaglandin D2 was blocked by simultaneous injection of a substance P antagonist (greater than or equal to 100 ng) but not by AH6809, a prostanoid EP1-receptor antagonist. Conversely, prostaglandin E2-induced hyperalgesia was blocked by AH6809 (greater than or equal to 500 ng) but not by the substance P antagonist. Prostaglandin F2 alpha had little effect on pain responses. These results demonstrate that both prostaglandin D2 and prostaglandin E2 exert hyperalgesia in the spinal cord, but in different ways.


Asunto(s)
Hiperalgesia/inducido químicamente , Hiperestesia/inducido químicamente , Nociceptores/efectos de los fármacos , Prostaglandinas/farmacología , Médula Espinal/efectos de los fármacos , Xantonas , Animales , Relación Dosis-Respuesta a Droga , Inyecciones Espinales , Masculino , Ratones , Nociceptores/fisiología , Médula Espinal/fisiopatología , Xantenos/farmacología
10.
J Neurol ; 241(9): 551-6, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7799004

RESUMEN

When recording the activity of the posterior cricoarytenoid muscle (PCA) with surface electrodes, there is contamination from the surrounding muscles such as the cricopharyngeal muscle. We therefore devised a new oesophageal catheter electrode of the separate type, having three individual surface electrodes for the PCA, cricopharyngeal muscle and diaphragm. The records obtained with this catheter demonstrated satisfactory separation between PCA and cricopharyngeal muscle activities. We used this catheter in patients with multiple system atrophy presenting with vocal cord paralysis, who were awake or asleep. There were two interesting electromyographical findings, which were inspiratory activity of the adductor muscle (the thyroarytenoid muscle) and fade-out of the abductor muscle, that is, PCA activity during sleep. Although vocal cord paralysis is one of the most serious life-threatening complications, the precise mechanism has not been clarified. We believe that our catheter may be useful in investigating the mechanism of vocal cord paralysis which could cause sudden death in neurodegenerative disorders, including multiple system atrophy.


Asunto(s)
Electromiografía/métodos , Músculos Laríngeos/fisiopatología , Atrofias Olivopontocerebelosas/complicaciones , Parálisis de los Pliegues Vocales/etiología , Anciano , Esclerosis Amiotrófica Lateral/complicaciones , Cateterismo/instrumentación , Enfermedades Cerebelosas/complicaciones , Electrodos , Electromiografía/instrumentación , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Shy-Drager/complicaciones , Parálisis de los Pliegues Vocales/diagnóstico , Parálisis de los Pliegues Vocales/fisiopatología
11.
Eur J Pharmacol ; 122(2): 173-9, 1986 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-3458588

RESUMEN

The effect of intracisternal administration of three major prostaglandins on nociceptive responses was evaluated in mice. Prostaglandin D2 had biphasic effects on pain thresholds (hot plate and acetic acid writhing tests) when given in a dosage range of 5 ng to 5 micrograms per mouse. Lower doses of prostaglandin D2 (less than or equal to 15 ng) increased the sensitivity to pain stimulation. Higher doses (greater than or equal to 50 ng) caused hypoalgesia, which was completely blocked by intracisternal injection of 500 pg of naloxone. Prostaglandin E2 (5 ng-5 micrograms) also had a biphasic effect on pain thresholds, similar to the effect of prostaglandin D2. However, the hypoalgesia caused by a higher dose of prostaglandin E2 (5 micrograms) was not blocked at all by naloxone doses of up to 500 ng. Prostaglandin F2 alpha had little effect on pain thresholds. These results indicate that each prostaglandin has a specific effect on the modulation of nociception.


Asunto(s)
Nociceptores/efectos de los fármacos , Prostaglandinas/farmacología , Animales , Cisterna Magna , Dinoprost , Dinoprostona , Inyecciones , Masculino , Ratones , Dolor/fisiopatología , Prostaglandina D2 , Prostaglandinas/administración & dosificación , Prostaglandinas D/farmacología , Prostaglandinas E/farmacología , Prostaglandinas F/farmacología , Tiempo de Reacción/efectos de los fármacos , Factores de Tiempo
12.
J Neurol Sci ; 130(2): 197-202, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8586986

RESUMEN

Vocal cord abductor paralysis (VCAP) is rare in Parkinson's disease (PD), while it is frequent in multiple system atrophy (MSA). Although VCAP is a life-threatening complication it has not yet been clarified whether there is any difference in the mechanism of VCAP between PD and MSA. Examining 3 autopsy-proven PD patients who developed severe VCAP requiring tracheostomy, we found the following differences in the mechanism of VCAP between MSA and PD: (1) clinical and laryngofiberscopic examination showed that VCAP in PD was not exacerbated during sleep, unlike in MSA; (2) On histological examination of the intrinsic laryngeal muscles, the posterior cricoarytenoid muscle demonstrated no abnormalities in PD, while the muscle showed characteristic neurogenic atrophy in MSA. There seemed to be two types of VCAP, namely the nonparalytic type observed in PD, and the paralytic type observed in MSA. Severe dysphagia requiring tube-feeding was common among PD patients who presented with VCAP. Although the relationship between VCAP and dysphagia is unknown, one should be aware of the possibility of fatal VCAP in PD patients with severe dysphagia.


Asunto(s)
Músculos Laríngeos/patología , Atrofia Muscular/complicaciones , Enfermedad de Parkinson/complicaciones , Parálisis de los Pliegues Vocales/etiología , Anciano , Femenino , Humanos , Laringoscopía , Masculino , Persona de Mediana Edad , Atrofia Muscular/patología , Enfermedad de Parkinson/patología , Parálisis de los Pliegues Vocales/patología
13.
Br J Ophthalmol ; 68(5): 347-9, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6712915

RESUMEN

Pterygium is thought to be hyperaemia of fibrovascular tissue on to the cornea caused by ultraviolet radiation of sunlight. We observed a significantly high incidence of pterygia in welders who were exposed occupationally to excess ultraviolet radiation and found a close relationship between the incidence and the length of employment as a welder (r = 0.975, p less than 0.05). This study attempts to clarify the causative relationship between ultraviolet radiation and pterygia.


Asunto(s)
Enfermedades Profesionales/etiología , Pterigion/etiología , Rayos Ultravioleta/efectos adversos , Soldadura , Adolescente , Adulto , Anciano , Humanos , Japón , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/epidemiología , Pterigion/epidemiología
14.
Br J Ophthalmol ; 68(8): 544-8, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6743623

RESUMEN

To clarify the relationship between morphological changes in the corneal endothelium and ultraviolet (UV) radiation, specular microscopic examinations were performed on both eyes of 118 welders and 85 controls. The results showed: a decrease in the hexagonal cells in welders (20-29 years) in comparison with the controls (20-29) (p less than 0.05); an increase in the mean cell size of the endothelium and a decrease in the hexagonal cell population with increasing age in both groups; increases in standard deviation (SD) and the coefficient of variation (CV) of the mean cell size in both groups; increases in SD and CV of the mean number of cell cell sides in both groups; and no difference in the mean cell size between the two groups. These results show that UV radiation damages not only the corneal epithelium but also the endothelium, and suggest that it causes more pleomorphic change (a decrease in hexagonal cell population) than enlargement of the mean cell size.


Asunto(s)
Córnea/efectos de la radiación , Medicina del Trabajo , Rayos Ultravioleta/efectos adversos , Soldadura , Adulto , Anciano , Envejecimiento , Córnea/patología , Endotelio/patología , Endotelio/efectos de la radiación , Humanos , Masculino , Persona de Mediana Edad
15.
Toxicol Lett ; 63(3): 333-43, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1488781

RESUMEN

Blood and urine samples were collected at the end of an 8-h workshift from 30 male workers exposed to a mixture of n-hexane, ethyl acetate and toluene (each being about 2 ppm as geometric means) and also from 20 nonexposed male workers. Blood samples were analyzed for n-hexane and toluene, and urine samples were analyzed for n-hexane, toluene, 2,5-hexanedione (both with and without hydrolysis) and hippuric acid. Based on the correlation between biological exposure indicators and solvent concentrations in air, sensitivity as an exposure indicator was compared between solvents in blood and solvents or metabolites in urine in terms of the lowest solvent concentration at which the exposed subjects can be statistically separated from the nonexposed. Both n-hexane and toluene in blood were sensitive enough to detect the exposure at 6.1 ppm and 1.4 ppm, respectively. n-Hexane exposure below 2 ppm was detectable also by urinalysis for 2,5-hexadione without hydrolysis. Urinary hippuric acid, however, failed to detect low toluene exposure under the conditions studied. Of additional interest is the fact that toluene in urine correlated significantly with toluene in air, which apparently deserves further study for confirmation.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Monitoreo del Ambiente , Hexanos/análisis , Exposición Profesional , Tolueno/análisis , Acetatos/análisis , Contaminantes Ocupacionales del Aire/sangre , Contaminantes Ocupacionales del Aire/orina , Semivida , Hexanos/sangre , Hexanos/orina , Hexanonas/orina , Hipuratos/orina , Humanos , Masculino , Sensibilidad y Especificidad , Tolueno/sangre , Tolueno/orina
16.
Toxicol Lett ; 66(1): 53-61, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8427021

RESUMEN

The nephrotoxicity of dimethylarsinic acid (cacodylic acid, DMA) was examined in male and female F344/DuCrj rats. DMA administered perorally at doses of 113, 85, and 57 mg/kg for 4 weeks produced dose-related decreases in body weight and survival rate in both sexes. Mortality was higher and appeared more quickly in females than in males. Histopathological findings in the kidney were proximal tubular degeneration and necrosis, as well as papillary necrosis, and hyperplasia of the epithelium covering the papillae. Since extensive proximal tubular necrosis was observed only in dead animals of both sexes, and not in survivors or the controls, it was therefore concluded that the main cause of death could be attributed to nephrotoxicity of DMA. The results thus show that DMA is nephrotoxic to both male and female rats.


Asunto(s)
Ácido Cacodílico/toxicidad , Enfermedades Renales/inducido químicamente , Administración Oral , Animales , Peso Corporal/efectos de los fármacos , Femenino , Necrosis de la Corteza Renal/inducido químicamente , Necrosis Papilar Renal/inducido químicamente , Necrosis Tubular Aguda/inducido químicamente , Túbulos Renales Proximales/efectos de los fármacos , Túbulos Renales Proximales/patología , Masculino , Ratas , Ratas Endogámicas F344
17.
Toxicol Lett ; 62(2-3): 247-53, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1412510

RESUMEN

Stoichiometric conversion of methyl acetate to methanol in vitro was detected when methyl acetate was incubated with blood for 2 to 8 h. The velocity of the reaction was so fast that almost all of methyl acetate disappeared in 8 h. The methanol formation was further confirmed by means of gas-chromatography-mass spectrometry. The capacity to hydrolyze methyl acetate was evenly distributed in cellular and noncellular fractions of blood, but not in urine. The significance of the observation is discussed in relation to biological monitoring of exposure to industrial ester solvents by means of head-space gas-chromatography of blood samples.


Asunto(s)
Acetatos/metabolismo , Metanol/metabolismo , Acetatos/sangre , Acetatos/orina , Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Hidrólisis , Masculino
18.
Toxicol Lett ; 62(1): 85-91, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1509510

RESUMEN

An occupational health study was conducted on 45 acetone-exposed male workers in combination with 343 non-exposed men to examine the quantitative relationship between the intensity of acetone vapor exposure and the concentration of acetone in urine. The time-weighted average acetone concentrations were measured by means of diffusive samplers with water as absorbent, whereas urine samples were collected at the end of the shift as well as before the shift on the next morning. Acetone concentration in shift-end urine did not increase when the workers were exposed to acetone up to approx. 15 ppm, and this was followed by a gradual increase at a higher atmospheric acetone concentration, in a manner dependent to acetone vapor concentration. The comparison in acetone concentrations between the urine samples collected at the shift-end and those before the shift of the next morning showed that the levels in two sets of samples were the same among those exposed to 15 or less ppm acetone, whereas acetone in the shift-end samples was significantly higher than the counterpart levels in the pre-shift samples among those exposed to acetone at more than 15 ppm.


Asunto(s)
Acetona/orina , Exposición Profesional , Administración por Inhalación , Contaminantes Ocupacionales del Aire/análisis , Contaminantes Ocupacionales del Aire/orina , Humanos , Masculino , Análisis de Regresión , Factores de Tiempo
19.
Mutat Res ; 264(4): 163-70, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1723493

RESUMEN

The genotoxicity of beryllium, gallium and antimony compounds was studied with the rec, Salmonella mutagenicity and SCE assays. In the rec assay, all the salts of the metals, BeCl2, Be(NO3)2, GaCl3, Ga(NO3)3, SbCl3, SbCl5, and an oxide, Sb2O3, had DNA-damaging activity. None of the compounds was mutagenic to Salmonella. In the SCE assays using V79 cells, 2 antimony(III) compounds, SbCl3 and Sb2O3, and 2 beryllium compounds, BeCl2 and Be(NO3)2, induced SCEs significantly. Sb2O3, slightly soluble in water, was positive in both the rec assay and the SCE assay at very low doses.


Asunto(s)
Antimonio/farmacología , Berilio/farmacología , Daño del ADN , Galio/farmacología , Mutágenos/farmacología , Animales , Bacillus subtilis/efectos de los fármacos , Línea Celular , Pruebas de Mutagenicidad , Salmonella typhimurium/efectos de los fármacos , Intercambio de Cromátides Hermanas/efectos de los fármacos , Relación Estructura-Actividad
20.
J Toxicol Sci ; 6(1): 13-8, 1981 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7265326

RESUMEN

In rats exposed to styrene for 4 hours, the rate constant of elimination and biological half life of styrene were 0.11 and about 6 hours for adipose tissue, and 0.3 to 0.4 and about 2 hours for the other tissues, respectively. The relative ratio of apparent distribution of styrene decreased in the order adipose tissue much greater than liver greater than brain greater than kidney greater than blood not equal to spleen greater than muscle. Almost the same results were obtained in the experiment by intraperitoneal injection of styrene. Repeated 4-hour exposures at about 700 ppm daily for five days caused the results similar to those in a single exposure. A trend of increase in concentration of styrene was observed in adipose tissue by 5 successive intraperitoneal injections every 6 hours at a dose of 350 mg/kg.


Asunto(s)
Estirenos/metabolismo , Animales , Gases , Inyecciones Intraperitoneales , Cinética , Masculino , Ratas , Estirenos/administración & dosificación , Factores de Tiempo , Distribución Tisular
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