Effects of Extremely Low Frequency Elecromagnetic Fields on Thyroid Carcinogenesis Induced by N-bis(2-hydroxypropyl)nitrosamine and Sulfadimethoxine

PURPOSE: Long-term exposure to extremely low-frequency (60 Hz) electromagnetic fields (ELF-EMF) raises the questions of the induction of biological effects including tumorigenesis. One mechanism through which ELF-MFS could influence neoplastic development is the imbalance of cellular proliferation and cell apoptosis. The present study investigated the effect of ELF-EMF on chemically-induced thyroid carcinogenesis in a rat. METHODS: We examined cellular proliferation index measured by anti-Ki-67 antigen, apoptosis, apoptosis related proteins such as caspase 3 and p53, and cell cycle-related proteins (cyclin D1 and p21(WAF1/Cip1)). Forty Male F344 rats received a subcutaneous N-bis(2-hydroxypropyl)nitrosamine (DHPN, 2,800 mg/kg) injection, and 1 week later were allowed free access to drinking water containing sulfadimethoxine (0.1%) for 12 weeks. Twenty rats were exposed by ELF-EMF. During the carcinogenesis, sequential histological changes from hyperplasia, adenoma, and ultimately to overt carcinomas were noted. RESULTS: The exposure group of ELF-EMF, significantly increases the number size of carcinomas. Also, the proliferative and apoptotic indices were significantly increased in the ELF-EMF exposure group than in the control group. The caspase 3 protein expression did not show any significant changes between ELF-EMF group and control group. The p53 protein was not detected in both ELF-EMF exposure and control group. Among the cell cycle related proteins, cyclin D1, not p21(WAF1/Cip1), was significantly increased in adenomas and carcinomas in ELF-EMF exposure group compared with the control group. CONCLUSION: Exposure of ELF-EMF effects on chemically-induced rat thyroid carcinogenesis as results of altered increase of cellular proliferation, apoptosis, and cyclin D1 expression.

In vitroactivity of certain drugs in combination with plant extracts against staphylococcus aureus infections

This study has been done to evaluate the interaction between ethanolic extracts of Rhus coriaria [seed], Psidium guajava [Leaf], Lawsonid inermis [Leaf] and Sacropoterium spinosum [seed] and antimicrobial drugs including oxytetracycline HCl, enrbfloxacin, gentamicin sulphate and sulfadimethoxine against four clinical isolates of methicillin-resistant Staphylococcus aureus [MRSA]. Evaluation of the interaction between ethanolic extracts and different antimicrobial agents has been done using well-diffusion method. It showed that ethanolic extracts increase the inhibition zones of oxytetracycline HCl, gentamicin sulphate, and sulfadimethoxine, while combinations between these plant extracts and enrofloxacin decrease inhibition zone. This study probably suggests the possibility of concurrent use of these antimicrobial drugs and plant extracts in combination in treating infections caused by S. aureus strains or at least the concomitant administration may not impair the antimicrobial activity of these antibiotics

Determination of residues of sulphonamide in eggs and laying hens

Eggs were collected from different areas of Faisalabad city. The quantity of sulphonamides was determined in yolk, white and whole egg and compared with the permissible limit 1 micro g/ml for sulphadimethoxine available in literature. In another experiment, a group of hens were kept at a poultry farm after medicating them with darvisal liquid to see if the residues of sulphonamide pass into the eggs of poultry. The period of existence of residues was noted

Evaluation of the Bilirubin Ototoxicity using ABR and DPOAE in Jaundiced Gunn Rats / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: In neonatal hyperbilirubinemia, accumulation of unconjugated bilirubin in the central auditory pathway and basal ganglia may cause sensorineural hearing loss and neurologic sequelae. The effect of unconjugated bilirubin on the brain is known well through auditory brainstem responses (ABRs). However, there is no evidence of pathologic changes in the cochlea. Jaundiced (jj) Gunn rats have been used as a good animal model for hyperbilirubinemia-related auditory dysfunction. The purpose of this study is to evaluate the bilirubin ototoxicity using ABR and DPOAE in jaundiced Gunn rats before and after sulfadimethoxine injection. MATERIALS AND METHOD: Experiments were conducted on three homozygous (jj) P19 (postnatal 19 days) littermates, one heterozygous Gunn rat, five P21 jj littermates, and one nj Gunn rat littermate. P21 jj and nj Gunn rats were re-tested in three weeks in the same condition. ABR with 100-microsecond pulse width click and DPOAEs at 8 kHz, 16 kHz and 22 kHz were measured before and after 1 mg/kg sulfadimethoxine injection. RESULTS: The thresholds of ABR were elevated in P19 and P21 group within the first day after injection and became normalized at several days after injection. Delay of wave II, III, IV and V were also observed. DPOAE showed no significant change after injection in all groups, meaning that the cochlea was not damaged. CONCLUSION: This study shows that bilirubin ototoxicity is related with pathologic changes at or higher than the brainstem level with intact cochlear function. Changes in ABR findings were only observed in P19 and P21 groups because they had higher bilirubin level in blood and their central auditory pathway is more immature than that found in the P42 group. In this study, we also found the possibility of spontaneous recovery from hyperbilirubinemia-related auditory toxicity.

Açäo da anfotericina B e Levamisole em camundongos albinos inoculados com Paracoccidioidomicose Brasiliensis / Study on anphotericin B and levamisole in albino mice inoculated with paracoccidioides brasiliensis

Paracoccidioidomicose experimental, em camundongos albinos de 3-4 semanas de idade. Inoculaçäo de 0,5 ml de suspensäo, contendo 1x10(devada a sexta potência) células/ml de Paracoccidioides brasiliensis e tratamento com anfotericina B (1 mg/Kg) em doses diárias; com levamisole (3 mg/Kg) administrada em intervalos de 15 dias e em séries de uma dose por dia, em três dias consecutivos; e com anfotericina B e levamisole associadas, de maneira a cobrir o período de 50, 80 e 95 dias para necrópsia. Estudo comparativo do quadro histológico de fígado e baço, com ênfase em granulomas, parasitas, células de Küpffer, células gigantes, reaçäo linforreticular, folículos e amioloidose. O animal revela-se satisftório, como modelo experimetnal, porém de uso limitado, devido ao fenômeno de auto-cura. Isoladamente, anfotericina B é menos eficiente do que quando em associaçöes com levamisole, para a reduçäo do número de parasitas. Animais com amiloidose esplênica apresentam alto número de parasitas. O quadro reativo revela qe a açäo de levamisole, isolada ou combinadamente com anforicina B, induz aumento de defesa com notável incremento da açäo de células fagocitárias

Penfigoide de Lever como manifestacion de neoplasia interna. / Lever\"s pemphigoid as an internal neoplasm manifestation

El penfigoide de Lever, dermatosis relativamente comun, es poco citado en la bibliografia nacional. Al comunicar un caso asociado a linfoma, revisamos las ultimas comunicaciones internacionales. Destacamos los hallazgos histopatologicos, inmunologicos y ultraestructurales, asi como la existencia de casos frontera. Abogamos por la terapeutica combinada: corticoides mas sulfas lentas o sulfonas. Un esfuerzo estadistico mundial podria facilmente aclarar si esta afeccion puede mantenerse entre aquellas que los autores y el Dr. David Goldberg propponen denominar Procesos con Alto Riesgo de Carcinoma-Sarcoma" (P.A.R.C.S.). Descartar tal posibilidad en un proceso con tan evidente "desvio del sistema inmune" nos parece arriesgado