[Vulvar squamous cell carcinoma in young women with HPV negative]. / Carcinoma epidermoide de vulva en mujer joven con VPH negative.

BACKGROUND: The vulvar cancer is the fourth more frequent neoplasia after the endometrial, cervix and ovarian cancer. Normally, it has been related to old women of ages from 70 to 80 years old. Rarely, it has been detected cases in adult or young women. However, its incidence has been increased in the last years and in more early years. It is for this change in the incidence and its appearance in early years why a possible etiology has been looked for, opening different hypothesis that go from that related to the HPV to those that study an inflammatory chronic process as the basis for the carcinogenesis. CLINICAL CASE: In this article, it has been presented the case of a woman who is 34 years old with negative VPH that made her debut with epidermoid carcinoma of the vulva moderately different and on purpose of the case, we do a revision of the literature existent. CONCLUSIONS: Vulvar cancer diagnosed in young women as in older, but with different trends, risk factors and natural history. The case reported here escapes the theories studied so far so needed new lines of inquiry to investigate this form of presentation young woman, without HPV infection.

Radiation dosimetry and biodistribution in non-human primates of the sodium/iodide PET ligand [(18)F]-tetrafluoroborate.

BACKGROUND: [(18)F]-tetrafluoroborate is a PET radiotracer taken up by the sodium/iodide symporter (NIS). Albeit the in vivo behavior in rodents is similar to the (99m)Tc-pertechnetate, no studies exist in primates or in humans. The aims of this study were to evaluate the biodistribution of [(18)F]-tetrafluoroborate in non-human primates with PET and to estimate the absorbed dose in organs. METHODS: Whole-body PET imaging was done in a Siemens ECAT HR+ scanner in two male Macaca fascicularis monkeys. After an i.v. injection of 24.93 ± 0.05 MBq/kg of [(18)F]-tetrafluoroborate, prepared by isotopic exchange of sodium tetrafluoroborate with [(18)F]-fluoride under acidic conditions, eight sequential images from the head to the thigh (five beds) were collected for a total duration of 132 min. The whole-body emission scan was reconstructed applying attenuation and scatter corrections. After image reconstruction, three-dimensional volumes of interest (VOIs) were hand-drawn on the PET transaxial or coronal slices of the frame where the organ was most conspicuous. Time-activity curves for each VOI were obtained, and the organ residence times were calculated by integration of the time-activity curves. Human absorbed doses were estimated using the OLINDA/EXM software and the standard human model. RESULTS: [(18)F]-tetrafluoroborate was able to discriminate clearly the thyroid gland with an excellent signal-to-noise ratio. Most of the radiotracers (residence time) are localised in the organs that express NIS (stomach wall, salivary glands, thyroid, olfactory mucosa), are involved in excretion (kidneys and bladder), or reflect the vascular phase (heart and lungs). Considering the OLINDA source organs, the critical organs were the stomach wall, thyroid and bladder wall, with absorbed doses lower than 0.078 mGy/MBq. The effective dose was 0.025 mSv/MBq. CONCLUSIONS: [(18)F]-tetrafluoroborate is a very useful radiotracer for PET thyroid imaging in primates, with a characteristic biodistribution in organs expressing NIS. It delivers an effective dose slightly higher than the dose produced by (99m)Tc-pertechnetate but much lower than that produced by radioiodine in the form of (131)INa, (123)INa, or (124)INa.

PET imaging of thymidine kinase gene expression in the liver of non-human primates following systemic delivery of an adenoviral vector.

Non-invasive in vivo imaging of transgene expression is currently providing very important means to optimize gene therapy regimes. Results in non-human primates are considered the most predictive models for the outcome in patients. In this study, we have documented that tumour and primary cell lines from human and non-human primates are comparably gene-transduced in vitro by serotype 5 adenovirus expressing HSV1-thymidine kinase. Transgene expression can be quantified in human and monkey cultured cells by positron emission tomography (PET) imaging when transduced cells are incubated with a fluoride-18 labelled penciclovir analogue. In our hands, PET images of cell cultures estimate the number of transduced cells rather than intensity of transgene expression once a threshold of TK per cell is reached. Interestingly, in vivo systemic administration of a clinical grade recombinant adenovirus expressing TK into macaques gives rise to an intense retention of the radiotracer in the liver parenchyma, providing an experimental system to visualize transgene expression that ought to be similar in human and macaques. Such imaging methodology might contribute to improve strategies based on adenoviral vectors.

The effect of natural UV-B radiation on a perennial Salicornia salt-marsh in Bahía San Sebastián, Tierra del Fuego, Argentina: a 3-year field study.

The Antarctic ozone hole and a general depletion of the stratospheric ozone layer cause increased levels of ultraviolet-B solar radiation (UV-B) over Tierra del Fuego, the southernmost tip of South America. For three consecutive growing seasons (1997-2000), we studied the biological impacts (morphology, physiology, demography and phenology) of natural UV-B radiation on a perennial Salicornia ambigua Michx. community in San Sebastian Bay (53 degrees S and 68 degrees W), Tierra del Fuego, Argentina. This is the first UV-B screening experiment on a subantarctic halophytic community. The shortwave UV-B spectrum (280 to 320 nm) was excluded by covering plots with UV-B blocking film (Mylar). These plots were compared to controls covered with UV-B transparent (Aclar) plastic screens, and unscreened plots. Shoot length in Salicornia was not affected by UV-B. Exposure to natural UV-B reduced biomass and density (by 17% and 38%, respectively). Concentration of UV-shielding pigments and cuticle thickness were both significantly higher (25-48% and 21-40%, respectively) in plants receiving ambient UV-B. The increase in cuticle thickness persisted throughout the growing season, whereas pigment concentration was higher at the beginning of the growing season. Also, the number of dead shoots was higher in plants exposed to UV-B. At the end of the growing season (March) shoot mortality was higher in plants exposed to ambient UV-B, and post-flowering senescence was 30 days earlier. Slight changes in the relative composition of Salicornia to Puccinellia were seen. The reduction observed in Salicornia shoot density under ambient UV-B was cumulative over time; 23% in the first growing-season, rising to 38% by the third growing-season. A similar incremental increase in pigment absorption at 305 nm was seen; 25% in the first and 48% in the third growing season.

Distribution of adrenomedullin and proadrenomedullin N-terminal 20 peptide immunoreactivity in the pituitary gland of the frog Rana perezi.

Adrenomedullin (AM) and proadrenomedullin N-terminal 20 peptide (PAMP) are two multifunctional peptides processed from a common precursor which have been described in numerous mammalian organs, including the pituitary gland. Previous studies have found AM immunoreactivity in neurohypophysis nerve fibers of amphibian pituitary. In the present study, immunocytochemical and Western blot analysis in the pituitary gland of the amphibian Rana perezi demonstrated in the adenohypophysis both AM and PAMP. AM-like immunoreactivity was found in a moderate number of endocrine cells of the pars distalis. In the neurohypophysis, AM was observed not only in nerve fibers of pars nervosa and axonal projections innervating the pars intermedia, but also in the outer zone of the median eminence. PAMP staining was observed in numerous endocrine cells scattered all over the pars distalis and in some cells of the pars tuberalis, but not in the neurohypophysis. In order to compare the quantity of AM and PAMP immunoreactivity between pars distalis of female and male specimens, an image analysis study was done. Significant differences for AM immunoreactivity (p<0.001) between sexes was found, the males showing higher immunostained area percentage. Differences of PAMP immunoreactivity were not significant (p=0.599). Western blot analysis detected bands presumably corresponding to precursor and/or intermediate species in the propeptide processing.