Sildenafil-associated hepatoxicity: a review of the literature.

Sildenafil citrate (Viagra®) is a vasoactive agent available worldwide since 1998 for the treatment of male erectile dysfunction. It is a selective phosphodiesterase type 5-enzyme inhibitor able to potentiate the downstream effects of nitric oxide on smooth muscle relaxation and vasodilation through its effects on the cyclic guanosine monophosphate (c-GMP) pathway in the erectile tissue of the penis. When sildenafil is orally administered, it is rapidly absorbed with a maximum plasma concentration achieved within 1 h and has a terminal half-life of between 3 to 6 h. The drug is extensively and rapidly metabolized by the liver, primarily by the CYP3A4 enzyme. Although the drug is well tolerated, specific adverse events have been observed, like flushing, headaches, dyspepsia, and visual disturbances. Liver toxicity related to sildenafil consumption has been considered a very rare event. However, in the last decade, some cases of sildenafil-associated hepatotoxicity have been reported. Furthermore, some hepatic intoxications have been reported after the intake of "natural" or "herbal" aphrodisiac supplements sold through Internet, sex shops, social media, and by word-of-mouth found to contain sildenafil and other phosphodiesterase type 5 (PDE-5) inhibitors. Studies investigating a possible link between sildenafil use and liver damage are limited, and the underlying mechanism responsible for hepatotoxicity is still missing. Studies in animals evidence that the hematopoietic function of the liver may have severely been affected as a result of a probable toxic effect of sildenafil. Here, the studies reporting liver toxicity by sildenafil in humans and in animals are reported and discussed.

Endometrial carcinoma: MR staging and causes of error.

PURPOSE: This study was undertaken to prospectively determine the diagnostic capabilities of magnetic resonance (MR) imaging in detecting myometrial and cervical invasion and lymph node involvement in endometrial carcinoma and to identify the causes of errors in staging endometrial carcinoma. MATERIALS AND METHODS: Twenty consecutive patients with a histological diagnosis of endometrial carcinoma underwent preoperative MR imaging. MR findings were compared with surgical staging, considered as the standard of reference. RESULTS: In assessing myometrial invasion, MR imaging showed 70% accuracy, 80% sensitivity, 40% specificity, 80% positive predictive value (PPV), and 40% negative predictive value (NPV). In detecting cervical invasion, MR imaging had 95% accuracy, 100% sensitivity, 94.4% specificity, 66.7% PPV, and 100% NPV. In evaluating lymph node involvement, MR imaging showed 100% accuracy, sensitivity, specificity, PPV and NPV. Errors in evaluating myometrial invasion were caused by polypoid tumour, adenomyosis and leiomyomas, whereas those in evaluating cervical invasion were caused by dilatation and curettage. CONCLUSIONS: MR imaging is a reliable technique for preoperative evaluation of endometrial carcinoma. Its main limitation is differentiating between stage IA and IB carcinomas, which is not highly important for surgical planning. Cooperation between the gynaecologist and radiologist is mandatory to avoid staging errors.

Cellular distribution of bovine leukemia virus proteins gp51SU, Pr72(env), and Pr66(gag-pro) in persistently infected cells.

Monoclonal antibodies (mAbs) against bovine leukemia virus (BLV) mature proteins and precursors were used to map the localization of these proteins in persistently infected non-lymphocytic cell lines using immunofluorescence assay (IFA) and immuno-electron microscopy. IFA staining was observed in the basolateral surface of live FLK-BLV cells. When using a mAb against Pr66(gag-pro), mottled pinpoint fluorescence was seen in the cell surface of polarized cells, but no reaction was observed in cells undergoing mitosis. However, a mAb against Pr72(env) stained only mitotic cells and cellular fragments. Additionally, in these dividing cells, this envelope (Env) precursor polyprotein was not evenly distributed but concentrated predominantly in only one daughter cell. To the best of our knowledge, this observation has not been reported previously, either for BLV or for other retroviruses. The results of immunogold electron microscopy confirmed the specificity of the mAbs in the intracellular level. In infected cells, Pr72(env) and gp51SU were seen in proximity at the plasma membrane in incipient budding sites. Additionally, the mAb against Pr72(env) also reacted with Env precursor polyproteins in the mitochondria of BLV-bat(2) ultrathin sections. These mAbs may be used as a tool for mapping virus excretion sites in the cell surface of naturally or in vitro infected cells in the different stages of the cell cycle.

[Primary polycythaemia vera in the elderly]. / La policitemia vera en el anciano.

We present an 86-years-old woman's case with paralysis in her left hand of abrupt apparition, accompanied by arterial hypertension and dizziness. The investigation revealed erythrocytosis, leukocytosis, thrombocytosis, with normal arterial O2 saturation (O2 SAT), increased of his red cell volume and blood viscosity. The polycythaemia vera (PV) was diagnose and the paralysis disappeared, when 24 hours before a phlebotomy was practiced, and the function was recovered by the hand. We analysed the presents diagnostics criteria of the disease defined by Polycythaemia Vera Study Group (PVSG). The different treatments for PV are discussed; in addition to venesection, conventional treatment include chemotherapy with hydroxyurea and pipobroman, as well as the erythropheresis, -interferon and aspirin. All of the treatments are associated with complications; thrombotic in the case of phlebotomy; malignancies and gastrointestinal bleeding in the case of myelosuppressive treatments and aspirin. We think the optimal treatment for PV is a judicious combination of the available alternatives, depending on the phase of the disease, and the age of the patient.

[Efficiency of essential oil (Satureja montana) in controlling the ascospherosis in the honey bee (Apis mellifera) under field conditions.]. / Eficacia del aceite esencial de ajedrea (Satureja montana) en el control de la ascosferosis de la abeja (Apis mellifera) en condiciones de campo.

With the aim of testing its effect in the control of ascosphaerosis in bees, the essential oil of ajedra was incorporated into three types of feed in five different concentrations. Syrup (water and honey) with 0.1% were the best tolerated by the bees, with no colonial changes after a single feed. Later, the ascosphaerosis was introduced in a controlled manner into eight hives. For this, a 10 e6/ml spore suspension was applied by nedulisor three times a week for four weeks to ensure its abundant presence inside the hives. This was continued for the next four weeks period, and at the same time portions of brood-comb in a known state (24 h before operculation) were removed from the hives and heat shocked for 24 h (22 -/+ 2 degrees C), then replaced in the hives for their opercultion, finally removing them and maintaining them at 35 degrees C and 70% relative humidity until the appearance of typical disease symptoms (mummification of the larvae).The hives were randomly divided into two groups of four. One group received 500 ml of syrup with 0.1% oil of ajedra, twice a week for four weeks. The other was kept as the control, receiving syrup without medication. 27.6% of the selected larvae in the treated hives showed mummification, compared with 79.1% in the control hives. The treatment was perfectly tolerated by the bee colonies, showing no changes in their subsequent development.

Prolonged immunostimulatory effect of low-dose polyethylene glycol interleukin 2 in patients with human immunodeficiency virus type 1 infection.

13 patients with human immunodeficiency virus type 1 infection class II-IV, but without opportunistic infection or neoplasm, received 6 micrograms (3.6 x 10(4) IU) of polyethylene glycol recombinant human interleukin 2 (PEG IL-2) intradermally twice a week for 4 mo were then followed for an additional 6 mo. Clinical, immunological, and viral parameters were monitored in the patients, all of whom were taking zidovudine. The cutaneous administration of PEG IL-2 resulted in an indurated zone resembling a delayed-type hypersensitivity response of 26 +/- 1 mm diameter (676 mm2) at 72-96 h after injection throughout the 4 mo of administration. This dose, which was appreciably lower than in most previous trials, was not associated with local or systemic toxicity. No increase in the viral burden of circulating leukocytes or plasma occurred. A number of immunological functions were stimulated by this course of therapy. All patients demonstrated high levels of lymphokine-activated killer cell activity by cells freshly removed from the circulation and in the absence of in vitro exposure to IL-2. Natural killer cell activity was also enhanced. Limiting dilution analysis revealed an increase in the frequency of IL-2-responsive cells from abnormally low to levels above normal during the course of injections. In a subgroup of four patients with > or = 400 CD4+ T cells/microliter at entry, there was a trend to sustained increases in CD4+ T cell numbers. However, this increase did not reach statistical significance. This subset of patients also exhibited higher proliferative responses to phytohemagglutinin as mitogen. Several of these effects persisted for 3-6 mo after cessation of therapy. In conclusion, low-dose IL-2 regimens lead to sustained immune enhancement in the absence of toxicity. We suggest pursuit of this approach for further clinical trials both as prophylaxis and therapy.