RESUMO
BACKGROUND: We investigated the prevalence of HIV and human papilloma virus (HPV) infection in men with penile carcinoma. METHODS: This retrospective study investigated all men with penile carcinoma at the Universitas Academic Hospital in Bloemfontein, South Africa (January 2000-December 2008). Patients' age, HIV status, histological type of carcinoma and evidence of HPV infection were recorded. Statistical analyses included Student's t-test and Fisher's exact test where appropriate (2-tailed p-value < 0.05 indicated statistical significant). RESULTS: Among 65 patients (mean age 50.9 years, range 37-69), the most common histological type was squamous cell carcinoma (80.0%). HIV status was known for 48 patients; 27 (56.2%) were HIV-positive. The mean age at presentation was 43.7 years (range 26-69) years in the HIV-positive and 57.2 years (range 26-89) years in the HIV-negative group. Approximately 55% of HIV-positive and 24% of HIV-negative patients showed histological evidence of HPV infection (p = 0.04). No significant difference was found with regard to histological type of carcinoma. CONCLUSION: Patients with penile carcinoma had a high prevalence of HIV infection. The HIV-positive group were significantly younger at presentation, with a higher prevalence of HPV infection, suggesting that HIV may contribute to HPV-associated penile cancer at a younger age.
Assuntos
Carcinoma de Células Escamosas/patologia , Infecções por HIV/epidemiologia , Neoplasias Penianas/epidemiologia , Neoplasias Penianas/patologia , Adulto , Distribuição por Idade , Idoso , Biópsia por Agulha , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/terapia , Causalidade , Estudos de Coortes , Comorbidade , Seguimentos , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Hospitais Universitários , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Penianas/terapia , Prevalência , Estudos Retrospectivos , Medição de Risco , África do SulRESUMO
Background: We investigated the prevalence of HIV and human papilloma virus (HPV) infection in men with penile carcinoma.Method: This retrospective study investigated all men with penile carcinoma at the Universitas Academic Hospital in Bloemfontein, South Africa (January 2000December 2008). Patients' age, HIV status, histological type of carcinoma and evidence of HPV infection were recorded. Statistical analyses included Student's t-test and Fisher's exact test where appropriate (2-tailed p-value < 0.05 indicated statistical significant).Results: Among 65 patients (mean age 50.9 years, range 3769), the most common histological type was squamous cell carcinoma (80.0%). HIV status was known for 48 patients; 27 (56.2%) were HIV-positive. The mean age at presentation was 43.7 years (range 2669) years in the HIV-positive and 57.2 years (range 2689) years in the HIV-negative group. Approximately 55% of HIV-positive and 24% of HIV-negative patients showed histological evidence of HPV infection (p = 0.04). No significant difference was found with regard to histological type of carcinoma.Conclusion: Patients with penile carcinoma had a high prevalence of HIV infection. The HIV-positive group were significantly younger at presentation, with a higher prevalence of HPV infection, suggesting that HIV may contribute to HPV-associated penile cancer at a younger age
Assuntos
Carcinoma , Pênis , África do SulRESUMO
Some properties of carbamoyl-phosphate synthetase (ammonia) were studied in rat-liver mitochondria made selectively permeable by pretreatment with toluene. The Michaelis constants for NH3, MgATP and HCO-3 were 0.7, 1.2 and 2 mM respectively. N-Acetylglutamate activated the enzyme with a Ka of about 0.1 mM. At saturating concentrations of substrates and effectors the enzyme was inhibited by 50% by carbamoyl phosphate at a concentration of 13 mM. Binding of N-acetylglutamate to carbamoyl-phosphate synthetase required the presence of both free Mg2+ ions and MgATP, and was inhibited by Ca2+ ions and by N-carbamoylglutamate. The known activation of carbamoyl-phosphate synthetase by free Mg2+ is due to an increased affinity of the enzyme for N-acetylglutamate. Binding of N-acetylglutamate to carbamoyl-phosphate synthetase was a slow process: at N-acetylglutamate concentrations below 0.5 mM maximal binding was not completed within 30 min. The rate of binding increased with increasing N-acetylglutamate concentrations. Dissociation of N-acetylglutamate from the enzyme was relatively fast, with a half-time of about 5 min. Under all conditions studied there was a close relationship between carbamoyl-phosphate synthetase activity and the amount of N-acetylglutamate bound to the enzyme. The data are discussed in relation to the control of carbamoyl-phosphate synthetase in the intact hepatocyte.