RESUMEN
PURPOSE: Meniere's disease (MD) is characterized by combined cochlear and vestibular symptoms. However, its underlying cause remains unclear, with low-to-mid-tone hearing impairment being predominantly reported. Moreover, predicting hearing improvement after disease onset is not possible. This study aimed to assess whether hearing improvement in patients with definite MD (DMD) could be predicted using inner ear contrast magnetic resonance imaging (IEC-MRI) and pure-tone audiometry (PTA) at disease attack. MATERIALS AND METHODS: Between April 2020 and March 2022, seven outpatients with DMD were enrolled based on the Bárány Society DMD criteria. The patients were divided into two groups: low-tone hearing loss (LTL) group and low-to-mid-tone hearing loss (LMTL) group. Hearing improvement rates as well as the possible inter-relation between endolymphatic hydrops and hearing improvement were evaluated. RESULTS: Endolymphatic hydrops was found in two of four LTL cases. One of three LMTL cases had prominent lymphedema. All patients with LTL but only one patient with LMTL had hearing improvement. Endolymphatic hydrops was not found to be correlated with hearing improvement. CONCLUSIONS: Estimating hearing improvement in patients with DMD using IEC-MRI was not possible. However, PTA showed better hearing prognosis in LTL than in LMTL. Therefore, estimating hearing improvement using PTA was possible at disease attack.
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Hidropesía Endolinfática , Pérdida Auditiva , Enfermedad de Meniere , Vestíbulo del Laberinto , Humanos , Enfermedad de Meniere/diagnóstico , Enfermedad de Meniere/diagnóstico por imagen , Audiometría de Tonos Puros , Pronóstico , Audiometría de Respuesta Evocada , Hidropesía Endolinfática/diagnóstico , Hidropesía Endolinfática/diagnóstico por imagen , Audición , Pérdida Auditiva/diagnóstico , Pérdida Auditiva/etiología , Imagen por Resonancia Magnética/métodosRESUMEN
The association between congenital facial paralysis and visual development has not been thoroughly studied. Of 27 pediatric cases of congenital facial paralysis, we identified 3 patients who developed amblyopia, a visual acuity decrease caused by abnormal visual development, as comorbidity. These 3 patients had facial paralysis in the periocular region and developed amblyopia on the paralyzed side. They started treatment by wearing an eye patch immediately after diagnosis and before the critical visual developmental period; all patients responded to the treatment. Our findings suggest that the incidence of amblyopia in the cases of congenital facial paralysis, particularly the paralysis in the periocular region, is higher than that in the general pediatric population. Interestingly, 2 of the 3 patients developed anisometropic amblyopia due to the hyperopia of the affected eye, implying that the periocular facial paralysis may have affected the refraction of the eye through yet unspecified mechanisms. Therefore, the physicians who manage facial paralysis should keep this pathology in mind, and when they see pediatric patients with congenital facial paralysis involving the periocular region, they should consult an ophthalmologist as soon as possible.
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Ambliopía/etiología , Electrodiagnóstico/métodos , Nervio Facial/fisiopatología , Parálisis Facial/congénito , Agudeza Visual/fisiología , Ambliopía/diagnóstico , Ambliopía/fisiopatología , Niño , Preescolar , Parálisis Facial/complicaciones , Parálisis Facial/fisiopatología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios RetrospectivosRESUMEN
BACKGROUND: The clinical significance of the Epstein-Barr virus (EBV) status and p16 expression was unknown in nasopharyngeal carcinoma (NPC). METHODS: We retrospectively studied our pathology database for 13 years to determine the prevalence of EBV and p16 expression and their association with prognosis in cases of NPC. We performed immunohistochemistry for the p16 protein and in situ hybridization (ISH) for EBV-encoded small RNAs and human papillomavirus (HPV) DNA. RESULTS: Of the 43 patients with NPC, 27 (63%), 6 (14%), and 10 (23%) cases were EBV positive, EBV negative with keratinization, and EBV negative without keratinization, respectively. No cases were HPV positive by ISH. Among the 21 EBV-positive tumours that were tested for p16, only 2 tumours were p16 positive. The keratinization-positive group included only males, typically >60 years of age (5 of 6) and with T4 tumours (3 of 6). In contrast, the EBV-positive cohort tended to be younger (<60 years, 13 of 27) and have progressive N-stage tumours (N2-3, 14 of 27). The keratinization and EBV-negative cohort included predominantly males (9 of 10) who were likely p16 negative (4 of 10) and smokers (7 of 10). Multivariate analysis confirmed that keratinization was an independent prognostic factor for progression-free survival. CONCLUSION: In areas, such as Japan, that are nonendemic for both EBV and HPV, the causality of NPC appears to be more heterogeneous.
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Carcinoma/metabolismo , Carcinoma/virología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Infecciones por Virus de Epstein-Barr/complicaciones , Herpesvirus Humano 4/aislamiento & purificación , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/virología , Infecciones por Papillomavirus/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/patología , Infecciones por Virus de Epstein-Barr/diagnóstico , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patología , Infecciones por Papillomavirus/diagnóstico , Estudios Retrospectivos , Adulto JovenRESUMEN
The pathogenesis of extranodal natural killer/T-cell lymphoma (ENKTL) remains largely unknown. Herein, we present a case of ENKTL that may have occurred during the treatment of Actinomyces infection. A 69-year-old woman was admitted to our hospital with nasal bleeding, and a nasopharyngeal mass was observed. The patient was diagnosed with Actinomyces infection on biopsy, and oral antibiotics were administered. The tumor decreased in size; however, swelling of the nasal mucosa and perforation of the nasal septum were observed. A biopsy revealed a recurrence of Actinomyces infection, and oral antibiotics were again administered. The mucosal swelling improved temporarily, but the condition gradually deteriorated. The patient was diagnosed with ENKTL based on a third biopsy. Retrospective evaluation of the biopsies showed that there were no CD56-positive cells in the first specimen; however, the number of CD56-positive cells gradually increased in the second and third specimens. We retrospectively observed the occurrence of ENKTL under chronic inflammatory conditions due to Actinomyces infection in this case. In addition, this case suggests that the possibility of malignancy must be considered when managing such patients with Actinomyces infection.
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Mitochondrial dysfunction has been implicated in numerous common diseases as well as aging and plays an important role in the pathogenesis of sensorineural hearing loss (SNHL). In the current study, we showed that supplementation with germanium dioxide (GeO2) in CBA/J mice resulted in SNHL due to the degeneration of the stria vascularis and spiral ganglion, which were associated with down-regulation of mitochondrial respiratory chain associated genes and up-regulation in apoptosis associated genes in the cochlea. Supplementation with taurine, coenzyme Q10, or hydrogen-rich water, attenuated the cochlear degeneration and associated SNHL induced by GeO2. These results suggest that daily supplements or consumption of antioxidants, such as taurine, coenzyme Q10, and hydrogen-rich water, may be a promising intervention to slow SNHL associated with mitochondrial dysfunction.
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Pérdida Auditiva Sensorineural , Ubiquinona , Ratones , Animales , Ubiquinona/farmacología , Taurina/farmacología , Ratones Endogámicos CBA , Pérdida Auditiva Sensorineural/inducido químicamente , Pérdida Auditiva Sensorineural/genética , Pérdida Auditiva Sensorineural/prevención & control , Cóclea , MitocondriasRESUMEN
BACKGROUND: Anaplastic thyroid cancer is a rare and rapidly progressive cancer with an extremely poor prognosis. Besides surgical control, no clear treatment has been found, mainly due to the small population affected and high mortality rate. AIMS: To propose evidence-based treatment guidelines based on a 5-year retrospective study of patients with anaplastic thyroid cancer treated at our facility. There have been no clearly defined guidelines for treatment plan for undifferentiated thyroid cancer. Our paper presents a retrospective analysis on the treatment of patients with undifferentiated thyroid cancer at our hospital. METHODS AND RESULTS: We retrospectively evaluated the data of patients diagnosed with anaplastic thyroid cancer from April 2017 to March 2022. The total number of patients diagnosed and treated was seven. Two of these patients had operable cancer; five were inoperable and treated with lenvatinib or paclitaxel maintenance therapy. The median time from the first visit to death was 3.84 months, and six of the seven patients died before this study started. Three of them had Stage IVB cancer and died due to deterioration of their general condition, including lung metastasis; the other three had Stage IVC cancer and died of suffocation. The survivor had Stage IVB cancer, was treated by surgery combined with chemical radiotherapy, and survived >240 days. CONCLUSION: Considering the above findings, personalized surgical treatment should be prioritized to prevent suffocation. Especially in Stage IVB cancer, local control can be achieved by surgical and anticancer drug treatment to avoid death from suffocation.
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Carcinoma Anaplásico de Tiroides , Neoplasias de la Tiroides , Humanos , Carcinoma Anaplásico de Tiroides/diagnóstico , Carcinoma Anaplásico de Tiroides/terapia , Estudios Retrospectivos , Asfixia , Neoplasias de la Tiroides/terapia , Neoplasias de la Tiroides/patología , PronósticoRESUMEN
Carotid artery injury is a rare disease often caused by neck trauma or irradiation of head and neck cancer. It is not easy to diagnose quickly without these backgrounds. Herein, we report a case of a 52-year-old man with no history of trauma or irradiation whose carotid artery was found to be injured. It was suggested that patients without any other disease but hypertension could have carotid artery injury. Additionally, it was challenging to detect extravasation from the carotid artery by computed tomography scan and ultrasonography in the emergency department. We should consider the possibility of carotid artery injury when examining patients with sudden neck swelling, even without any history of trauma or irradiation.
RESUMEN
OBJECTIVE: To investigate the clinical and electrophysiological features of facial nerve paralysis (FNP) due to benign temporal bone masses (TBMs) and elucidate its differences as compared with Bell's palsy. METHODS: FNP assessed by the House-Brackmann (HB) grading system and by electroneurography (ENoG) were compared retrospectively. RESULTS: We reviewed 914 patient records and identified 31 patients with FNP due to benign TBMs. Moderate FNP (HB Grades II-IV) was dominant for facial nerve schwannoma (FNS) (n=15), whereas severe FNP (Grades V and VI) was dominant for cholesteatomas (n=8) and hemangiomas (n=3). The average ENoG value was 19.8% for FNS, 15.6% for cholesteatoma, and 0% for hemangioma. Analysis of the correlation between HB grade and ENoG value for FNP due to TBMs and Bell's palsy revealed that given the same ENoG value, the corresponding HB grade was better for FNS, followed by cholesteatoma, and worst in Bell's palsy. CONCLUSIONS: Facial nerve damage caused by benign TBMs could depend on the underlying pathology. Facial movement and ENoG values did not correlate when comparing TBMs and Bell's palsy. When the HB grade is found to be unexpectedly better than the ENoG value, TBMs should be included in the differential diagnosis.
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Neoplasias de los Nervios Craneales/complicaciones , Enfermedades del Nervio Facial/complicaciones , Parálisis Facial/etiología , Índice de Severidad de la Enfermedad , Neoplasias Craneales/complicaciones , Hueso Temporal , Adolescente , Adulto , Anciano , Parálisis de Bell/etiología , Colesteatoma/complicaciones , Electrodiagnóstico , Femenino , Hemangioma/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Neurilemoma/complicaciones , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: We aimed to determinate the prognostic value of lymphovascular invasion in the specimens resected during total laryngopharyngectomy for hypopharyngeal carcinoma. METHODS: Patients who underwent total laryngopharyngectomy at our institution between 2004 and 2014 were included in this study and retrospectively analyzed. We then discriminated for vascular invasion and lymphatic invasion of the primary tumor in all cases. RESULTS: We reviewed 135 records (120 men and 15 women; age range, 36-84 years). Tumors with lymphatic invasion tended to be associated with more metastatic lymph nodes and extracapsular spread (ECS) of metastatic lymph nodes. Tumors with vascular invasion tended to be associated with nonpyriform sinus locations. In a multivariate analysis, nonpyriform sinus locations, >3 metastatic lymph nodes, and vascular invasion remained significant prognostic factors for overall survival (OS); in recursive partitioning analysis, ECS and vascular invasion remained important categorical variables for OS. CONCLUSION: Vascular invasion is a strong prognostic biomarker for advanced hypopharyngeal carcinoma. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1535-1543, 2017.
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Neoplasias Hipofaríngeas/patología , Vasos Linfáticos/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Neoplasias Hipofaríngeas/mortalidad , Neoplasias Hipofaríngeas/cirugía , Laringectomía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Análisis Multivariante , Invasividad Neoplásica , Faringectomía , Pronóstico , Estudios Retrospectivos , Análisis de SupervivenciaRESUMEN
OBJECTIVES/HYPOTHESIS: We aimed to determine the effectiveness of induction chemotherapy for treating p16-positive oropharyngeal cancer in our department. STUDY DESIGN: This was a retrospective case series to assess treatment effectiveness. METHODS: We administered induction chemotherapy to patients with stage III to IV oropharyngeal p16-positive squamous cell carcinoma between 2008 and 2013. Induction chemotherapy was administered using combinations of docetaxel, cisplatin, and 5-fluorouracil. We measured the survival rates using the Kaplan-Meier method and log-rank test. RESULTS: We reviewed 23 patients (18 men and 5 women; age, 42-79 years). Induction chemotherapy resulted in partial or complete remission (20 patients) and in stable (2 patients) or progressive (1 patient) disease. In partial or complete remission, subsequent radiotherapy was performed in 16 patients, chemoradiotherapy in two, and transoral resection in two. In stable or progressive disease, subsequent open surgery was performed. Overall, one patient died of cervical lymph node metastasis, one died of kidney cancer, and one died of myocardial infarction. Event-free, distant-metastasis-free survival was present for 20 patients. The 3-year disease-specific survival was 95%; the overall survival was 87%. Two patients required gastrostomies during chemoradiotherapy and three required tracheotomies, but these were closed in all patients. CONCLUSION: The therapeutic response to induction chemotherapy for p16-positive oropharyngeal cancer was good. Partial or complete remission was achieved in almost 90% patients, and control of local and distant metastases was possible when it was followed by radiotherapy alone or with transoral resection of the primary tumor. A multicenter study is required to confirm these findings. LEVEL OF EVIDENCE: 4.
RESUMEN
Previously we reported a lack of modification by cinnamaldehyde (CNMA) of development of lung proliferative lesions induced by urethane in CB6F1-TgHras2 (rasH2) mice. In the present study, we re-evaluated CNMA effects using the same rasH2 strain and non-transgenic littermates initiated with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Sixteen mice/strain/sex received intraperitoneal NNK injections at a dose of 3 mg/mouse once a week for 2 weeks followed by free feeding of commercial diet containing 5000 ppm CNMA for 26 weeks. Additional groups were maintained without NNK injection and/or CNMA feeding for 28 weeks. Lung tumors were induced by NNK in both rasH2 and non-Tg males and females at incidence ranging from 63 to 100%. CNMA treatment significantly reduced the combined incidence of adenomas and carcinomas from 86 to 31% in rasH2 males (P<0.05), but no significant influence was evident in females. The multiplicity of NNK-induced lung tumors was also significantly reduced in rasH2 males given CNMA (P<0.01). Similar effects were also observed in non-Tg females given CNMA after NNK initiation. The results of our study strongly indicate that CNMA is capable of inhibiting development of NNK-initiated pulmonary tumorigenesis in rasH2 and non-Tg mice.
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Carcinógenos/farmacología , Neoplasias Pulmonares/prevención & control , Nitrosaminas/farmacología , Proteínas ras/genética , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos , Ratones TransgénicosRESUMEN
In our previous study, uterine endometrial stromal sarcomas and atypical hyperplasias of the endometrial glands were induced in heterozygous p53 deficient mice (p53 (+/-) mice) of the CBA strain given a single dose of N-ethyl-N-nitrosourea (ENU). In order to clarify whether uterine tumors can be induced in transgenic mice carrying a human prototype c-Ha-ras gene (rasH2 mice) that are very susceptible to genotoxic carcinogens, rasH2 mice and their wild-type littermates received an intraperitoneal injection of 120 or 0mg/kg body weight of ENU followed by no further treatment for 22 weeks. Eighteen and 94% of ENU-treated rasH2 mice had uterine endometrial adenocarcinomas and atypical hyperplasias, respectively. Other malignant and benign tumors such as lung alveolar/bronchiolar adenomas and carcinomas, forestomach squamous cell papillomas and carcinomas, splenic hemangiomas/sarcomas, skin papillomas, malignant lymphomas and harderian gland adenomas were also observed in ENU-treated rasH2 mice. The result in the present study suggests that female rasH2 mice are very susceptible to uterine carcinogenesis, providing a useful model for ENU-induced uterine epithelial tumors.
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Adenocarcinoma/genética , Alquilantes/toxicidad , Neoplasias Endometriales/genética , Etilnitrosourea/toxicidad , Genes ras , Predisposición Genética a la Enfermedad , Adenocarcinoma/inducido químicamente , Adenocarcinoma/patología , Animales , Neoplasias Endometriales/inducido químicamente , Neoplasias Endometriales/patología , Femenino , Inyecciones Intraperitoneales , Ratones , Ratones Endogámicos CBA , Ratones Transgénicos , Mutación PuntualRESUMEN
In order to improve the sensitivity of our previously established thyroid carcinogenesis model and to clarify whether endocrine disrupting chemicals with weak estrogenic activity have any modifying effects on the development of thyroid proliferative lesions, 6-week-old female castrated F344 rats were first given a single subcutaneous injection of 2000 mg/kg body weight of N-bis(2-hydroxypropyl)nitrosamine. From 1 week later, they received diets with: no supplement (basal diet (BD) group); cholesterol pellets containing 0.5 mg 17 beta-estradiol 3-benzoate (EB); or diet admixed with 1000 ppm methoxychlor (MXC) or 10,000 ppm bisphenol A (BPA) for 20 weeks. Furthermore, additional groups were administered 200 ppm sulfadimethoxine (SDM) in the drinking water simultaneously with the BD, EB, MXC or BPA treatments. Thyroid follicular cell hyperplasias, adenomas and/or carcinomas were induced only in the EB+SDM group, the incidences of non-malignant lesions being significantly increased, as compared with the BD+SDM group values. Furthermore, the serum level of thyroid stimulating hormone (TSH) was significantly increased in this group. No significant variation in quantitative values for thyroid proliferative lesions or TSH levels were observed in the other treated groups. The results of the present study convincingly indicate that EB, with strong estrogenic activity, but not MXC and BPA, with weak estrogenic activities, exerts promoting effects on thyroid carcinogenesis in rats. The present modified rat two-stage thyroid carcinogenesis model appears to have advantages over our previous model for screening purposes.
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Adenoma/inducido químicamente , Carcinógenos/toxicidad , Sistema Endocrino/efectos de los fármacos , Estradiol/análogos & derivados , Estradiol/toxicidad , Nitrosaminas/toxicidad , Neoplasias de la Tiroides/inducido químicamente , Adenoma/sangre , Adenoma/patología , Animales , Compuestos de Bencidrilo , Peso Corporal/efectos de los fármacos , Colesterol/metabolismo , Modelos Animales de Enfermedad , Estrógenos no Esteroides/toxicidad , Femenino , Metoxicloro/toxicidad , Tamaño de los Órganos/efectos de los fármacos , Ovariectomía , Fenoles/toxicidad , Ratas , Ratas Endogámicas F344 , Sulfadimetoxina/toxicidad , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/patología , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/patología , Tirotropina/sangreRESUMEN
Modifying potential of annatto extract (norbixin) on liver carcinogenesis was investigated in male F344/DuCrj rats initially treated with N-nitrosodiethylamine (DEN). Two weeks after a single dose of DEN (200 mg/kg, intraperitoneally), rats were given annatto extract at dietary levels of 0, 0.03, 0.1 and 0.3%, or phenobarbital sodium at 0.05% as a positive control for 6 weeks. All animals were subjected to partial hepatectomy at week 3, and were killed at week 8. There were no deaths related to annatto extract ingestion, and the treatment had no effects on body weights, or food and water consumption. Statistically significant increases of absolute and relative liver weights were apparent in the 0.1 and 0.3% groups. However, annatto extract did not significantly increase the quantitative values for glutathione S-transferase placental form positive liver cell foci observed after DEN initiation, in clear contrast to the positive control case. The results thus demonstrate that annatto extract at a dietary level of 0.3% (200 mg/kg/day) lacks modifying potential for liver carcinogenesis in our medium-term bioassay system.
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Carcinógenos/toxicidad , Carotenoides/toxicidad , Neoplasias Hepáticas/patología , Fenobarbital/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Pruebas de Carcinogenicidad , Modelos Animales de Enfermedad , Colorantes de Alimentos , Hígado/anatomía & histología , Hígado/efectos de los fármacos , Neoplasias Hepáticas/inducido químicamente , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Endogámicas F344RESUMEN
To clarify the threshold dose of thyroid tumor-promoting effects of xylazine hydrochloride (XZ), male F344 rats received pulverized basal diet containing 0, 250, 500, or 1000 ppm XZ for 26 weeks with or without initiation of 2400 mg/kg N-bis(2-hydroxypropyl)nitrosamine (DHPN). Thyroid weights significantly increased in the groups with or without DHPN initiation that were given 500 ppm XZ or more. The serum thyroxine (T4) and triiodothyronine (T3) levels decreased significantly in the XZ 250 and XZ 1000 ppm groups, respectively, although there were no remarkable changes in the serum thyroid-stimulating hormone (TSH) levels. Histopathologically, follicular cell hyperplasias and adenomas were induced in the DHPN-alone and DHPN+XZ groups, and the incidences and multiplicities of these lesions in the DHPN groups treated with 500 ppm XZ or more were significantly higher than those in the DHPN alone group. These results suggest that the threshold dose of rat thyroid tumor-promoting effects of XZ is between 250 and 500 ppm under the present experimental condition.
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Agonistas alfa-Adrenérgicos/toxicidad , Neoplasias de la Tiroides/inducido químicamente , Xilazina/toxicidad , Animales , Peso Corporal , Pruebas de Carcinogenicidad , Carcinógenos/toxicidad , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos , Masculino , Nitrosaminas/toxicidad , Tamaño de los Órganos , Ratas , Ratas Endogámicas F344 , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/patología , Neoplasias de la Tiroides/patología , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangreRESUMEN
Phenolphthalein has carcinogenic activity, causing malignant lymphomas in B6C3F1 mice at a dietary dose of 3000 ppm in a 2-year carcinogenicity study and in female heterozygous p53-knockout TSG mice (C57BL/6 background) at the same dose in a 6-month study. To examine whether carcinogenic potential of phenolphthalein can be detected in other p53-knockout mouse [p53 (+/-)] strains such as p53 (+/-) CBA mice or p53 (+/-) CIEA mice (C57BL/6 background) and their littermates, they were given a diet containing 0, 6000 or 12000 ppm for 6 months. Unequivocal induction of neoplastic lesions was not apparent, suggesting that p53 (+/-) CBA mice and p53 (+/-) CIEA mice are resistant to the induction of malignant lymphomas by the treatment of phenolphthalein.
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Carcinógenos/toxicidad , Genes p53 , Predisposición Genética a la Enfermedad , Neoplasias Experimentales/genética , Fenolftaleína/toxicidad , Administración Oral , Animales , Pruebas de Carcinogenicidad , Carcinógenos/administración & dosificación , Dieta , Relación Dosis-Respuesta a Droga , Heterocigoto , Masculino , Ratones , Ratones Endogámicos CBA , Ratones Noqueados , Neoplasias Experimentales/patología , Fenolftaleína/administración & dosificaciónRESUMEN
Previous studies showed that significant differences in mutation frequency of the human c-Ha-ras transgene between vinyl carbamate (VC)- and ethyl carbamate (urethane)-induced lung tumors were observed in rasH2 mice. It remains unclear why the point mutation frequency is extremely low in VC-induced lung tumors, although this compound is much more carcinogenic than urethane. In this study, we examined the somatic point mutations of the transgene at the RNA level in VC- and urethane-induced lung tumors of rasH2 mice. We did not find any mutation at codon 12 of the transgene in any of these lung tumors, but codon 61 showed frequent mutations in not only urethane-induced lung tumors (15 out of 16) but also VC-induced lung tumors (11 out of 11) in rasH2 mice. These results suggested that point mutations at codon 61 of the transgene play an important role in the carcinogenesis of VC- and urethane- induced lung tumors in rasH2 mice.
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Carcinógenos/toxicidad , Genes ras/genética , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/genética , Mutación Puntual , Uretano/análogos & derivados , Uretano/toxicidad , Animales , Codón , Cruzamientos Genéticos , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple , ARN Neoplásico/química , ARN Neoplásico/genéticaRESUMEN
Ethanol extracts of seeds of Psoralea corylifolia are proposed as food additives for processed food preservation. An extract was administered by admixing into diet at concentrations of 0, 0.375, 0.75, 1.5 or 3.0% to 10 male and 10 female F344 rats each for 90 days to evaluate its toxicity. Body weight gain, food consumption and food conversion efficiency (body weight gain per food consumption) were lower in the extract-treated animals, except for the 0.375% males, as compared to the control animals. Absolute and/or relative testes weights in the 1.5 and 3.0% groups and those of ovaries in the 3.0% group were significantly (p < 0.01) lower than in the control group. On histopathological examination, seminiferous tubular atrophy and Leydig cell atrophy in the testes, and epithelial cell atrophy in the seminal vesicles and prostate were observed in the 1.5 and 3.0% males. Decrease in the number of corpora lutea associated with frequent necrotic follicles in the ovaries in the 1.5 and 3.0% females and less frequent endometrial glands in the uterus in the 3.0% females were also detected. These results might suggest disruption of the hypothalamus-pituitary-gonadal axis in Psoralea corylifolia-treated rats as possible mechanisms underlying this gonadal toxicity.
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Ovario/efectos de los fármacos , Extractos Vegetales/toxicidad , Psoralea , Semillas , Testículo/efectos de los fármacos , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Energía/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Etanol/química , Femenino , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ovario/patología , Extractos Vegetales/administración & dosificación , Psoralea/química , Ratas , Ratas Endogámicas F344 , Testículo/patología , Pruebas de Toxicidad , Aumento de Peso/efectos de los fármacosRESUMEN
To investigate the liver tumorigenic sensitivity to various carcinogens in heterozygous p53 deficient [p53 (+/-)] CBA mice and their wild-type littermates [p53 (+/+) mice], 71 p53 (+/-) and 74 p53 (+/+) CBA mice (male, 6-12 weeks of age) were given diet containing 4,000 or 0 ppm flumequine (FL) for 26 weeks or a single intraperitoneal injection of 5 mg/kg body weights dimethylnitrosamine (DMN) at start of the study in Exp. 1, diet containing 6,000 or 0 ppm di(2-ethylhexyl)-phthalate (DEHP) for 26 weeks in Exp. 2, or diet containing 12,000, 6,000 or 0 ppm phenolphthalein (PhP) for 26 weeks in Exp. 3. All surviving animals of these groups were killed after completion of treatment of the test substances for 26 weeks. In the FL groups, the incidences of hepatocellular altered foci in p53 (+/-) mice, the multiplicities of those in p53 (+/-) and p53 (+/+) mice were significantly increased as compared to the corresponding control groups. The incidences and multiplicities of altered foci in the DMN groups were higher than those in the corresponding control groups in p53 (+/-) and p53 (+/+) mice, but no significant differences were indicated between the groups. There were no significant differences in the incidences, multiplicities and proliferating cell nuclear antigen labeling indices of altered foci in the FL or DMN groups between p53 (+/-) and p53 (+/+) mice. There were no significant differences in the incidences and multiplicities of altered foci between the DEHP or PhP and control groups. The present results suggest that p53 gene knocked out heterozygously does not enhance the chemical hepatocarcinogenesis in CBA mice.