Methylxanthines and benign proliferative epithelial disorders of the breast in women

The relationship between methylxanthine intake (caffeine, theobromine and theophylline) and risk of benign proliferative epithelial disorders (BPED) of the breast was examined in a case-control study conducted in Adelaide, South Australia. The study involved 383 cases with biopsy-confirmed BPED, 192 controls whose biopsy did not show epithelial proliferation, and 383 unbiopsied community controls individually matched to cases on age and area of residence. Overall, there was relatively little variation in risk of BPED with total methylxanthine intake, or with intake of caffeine or theophylline, while there was a positive association between theobromine intake and risk of BPED, but only when cases were compared with biopsy controls. Total methylxanthine intake was positively associated with risk of BPED showing severe atypia, but the trend in risk was statistically significant only when community controls formed the comparison group. These data do not provide strong support for an association between methylxanthine intake and risk of BPED.     

Thymic function in HIV infection

Current models hold that CD4+ depletion occurs as a result of direct and indirect effects of HIV, which both kill peripheral CD4+ cells and prevent adequate regeneration. Although age-associated involution diminishes thymic reserve and HIV is clearly thymotoxic, clinical trials have nonetheless shown that large proportions of patients who sustain adequate control of viral replication with highly active antiretroviral therapy (HAART) will demonstrate some evidence for thymic-dependent immune reconstitution, which is associated with improved immune competence. Furthermore, patients with insufficient or absent immune reconstitution following HAART generally lack evidence for thymopoiesis. Current studies are focused on improving our understanding of the causes for thymic failure in HIV infection. Recent work has demonstrated that some HIV strains, especially those that are CXCR4 trophic, are more thymotoxic and may contribute to irreversible thymic damage in this population.     

Tumor vascular signals in renal masses: detection with Doppler US

The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.     

Thymic function in HIV infection

Current models hold that CD4+ depletion occurs as a result of direct and indirect effects of HIV, which both kill peripheral CD4+ cells and prevent adequate regeneration. Although age-associated involution diminishes thymic reserve and HIV is clearly thymotoxic, clinical trials have nonetheless shown that large proportions of patients who sustain adequate control of viral replication with highly active antiretroviral therapy (HAART) will demonstrate some evidence for thymic-dependent immune reconstitution, which is associated with improved immune competence. Furthermore, patients with insufficient or absent immune reconstitution following HAART generally lack evidence for thymopoiesis. Current studies are focused on improving our understanding of the causes for thymic failure in HIV infection. Recent work has demonstrated that some HIV strains, especially those that are CXCR4 trophic, are more thymotoxic and may contribute to irreversible thymic damage in this population.     

Optimization of the weck-Cel collection method for quantitation of cytokines in mucosal secretions

Measurement of immune components in mucosal secretions is important for the evaluation of local immunity at the mucosal surfaces. The Weck-Cel ophthalmic sponge provides a method for the collection of these secretions. The sponge absorbs a relatively large volume of material, therefore allowing for quantitation of multiple immune components. Additionally, it provides a method in which the same device may be used to collect specimens from different mucosal sites, such as the genital tract and oral cavity. This sampling technique has successfully been applied for collection and measurement of antibody in oral and genital tract secretions. The purpose of this work was to optimize the extraction of protein from the sponge matrix. Of particular interest was the recovery of cytokines from the sponge. Satisfactory recovery of the cytokines interleukin 1beta (IL-1beta), IL-2, IL-5, IL-12, IL-6, IL-8, IL-10, and granulocyte-macrophage colony-stimulating factor was obtained. However, IL-4 and gamma interferon recovery rates remained low. Using an alteration of the published extraction method, cytokine concentrations were measured in cervical secretions from women using oral contraceptives. The data revealed detectable concentrations of IL-6, IL-10, IL-8, and IL-12 on cycle days 9 and 20. The proposed technique provides an easy, practical, and consistent method for collection of nonconventional body fluids, such as cervicovaginal fluids and saliva, for the assay of immunoglobulins and several cytokines.