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A new module of membrane-assisted solvent extraction (MASE) with miniaturized membrane bags was applied to the determination of seven volatile organic compounds (VOCs): chloroform, 1,1,1-trichloroethane, trichloroethylene, 1,1,2-trichloroethane, tetrachloroethene, 1,1,1,2-tetrachloroethane, 1,1,2,2-tetrachloroethane with boiling points between 61 and 147 degrees C in aqueous samples. Different from the known procedure the new, shortened membrane bags were filled with 100 microl of an organic solvent. The membrane bags were placed in a 20 ml headspace vial and filled with 15 ml of the aqueous sample. The vial was transferred into an autosampler where it was stirred for a definite time at elevated temperature. After the extraction, 1 microl of the organic extract was transferred into the spilt/splitless injector of a GC system equipped with an electron-capture detector. This work included optimization of the membrane device, the determination of the optimized extraction conditions such as stirring rate, extraction time and the impact of salt addition. The validation of the method involved repeatability, recovery and detection limit studies, followed of its application towards real water samples. The repeatability, expressed as the relative standard deviation of the peak areas of six extractions was below 10%. The detection limits (LODs) were between 5 ng/l (tetrachloroethene) and 50 ng/l (chloroform). Calibration was performed in a range from 5 ng/l to 150 microg/l, since the concentration in the aqueous samples was expected quite various in this concentration range. Five river water samples of Bitterfeld, Saxony-Anhalt, Germany were analyzed with miniaturized-MASE and the results were compared with those obtained with Headspace-Analysis. The method can be fully automated and moreover, it allows the simultaneous determination of volatile and semi volatile compounds.

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A hipofisectomia química ou neuroadenólise é um método de tratamento de dor secundária a metástases e que continua sendo muito util em pacientes portadores de tumores hormônio-dependentes. Os autores fazem uma revisäo da literatura, descrevem a técnica e discutem as indicaçöes deste método, que é bastante simples e eficaz

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Diffusion of alcohol in neuroadenolysis of pituitary gland (NALP) was observed by injection of horseradish peroxidase (HRP) or wheat germ agglutinin-HRP conjugates (WGA-HRP) into the pituitary of the cat. After small-amount injection of WGA-HRP into the pituitary, WGA-HRP labeling was observed markedly around the third ventricle and the ventral part of the hypothalamus. While, in large-amount injection of WGA-HRP, it extended to all of the ventricular systems and dipped into the substances of the brain and spinal cord through the ependyma. These results suggest that the main site of action for alcohol injected into the pituitary is probably the hypothalamus.

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Infertile patients who responded poorly in an in-vitro fertilization programme were treated with human menopausal gonadotrophin (HMG) or with pure follicle stimulating hormone (FSH) during continuous administration of a luteinizing hormone-releasing hormone (LHRH) agonist, to determine whether a low level of LH is required for follicle maturation. No statistically significant differences were detected in the dose of gonadotrophins, duration of treatment, oestradiol and LH levels, numbers of recovered oocytes, transferred embryos or fertilization rates. It is concluded that an absence of low levels of LH does not disturb follicular development in the follicular phase. Based on the low fertilization rates in the present study (0.32 with HMG versus 0.45 with FSH) the authors suggest that, as well as hormonal deficiency, other factors may also influence follicular and early embryonic development.

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We have reported the case of a 30-year-old woman with Cushing's disease who died of massive pulmonary thromboembolism 5 weeks after successful transsphenoidal hypophysectomy. Glucocorticoid excess appears to cause a hypercoagulable state, and consideration of this thromboembolic propensity and its potential duration after cure is indicated in all patients with Cushing's syndrome during the perioperative period. At the present time, we recommend the routine perioperative use of intermittent pneumatic compression in all patients with Cushing's disease or Cushing's syndrome.

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An experimental model for in vivo screening of aromatase inhibitors was developed which overcomes the interference of compounds centrally active via the pituitary-gonad axis. Mature female surgically or chemically hypophysectomised (hypx) rats were treated with the oestrogen precursor dehydroepiandrosterone sulphate (DHEAS), immediately followed by administration of the test compound. During the treatment period vaginal smears were prepared daily. In the hypx rats DHEAS was metabolised to oestrogens, which induced vaginal cornification. By determining oestradiol levels it was shown that the aromatase inhibitors tested antagonised oestrogen synthesis and, as a result, cornification was counteracted. 4-Hydroxyandrostenedione and SH 489 showed equipotent aromatase inhibition, whereas 19-mercapto-androstenedione (ORG 30365) was at least twice as potent as the former compounds. By using various oestrogen precursors the inhibition of the enzyme aromatase was demonstrated. For in vivo screening of compounds on their aromatase inhibiting activity the assay in hypx rats appeared to be very suitable and selective but, because anti-oestrogens also antagonise vaginal cornification, anti-oestrogenic activity has to be excluded.

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The aim of the study was to compare the ability to prevent endogenous luteinizing hormone interferences, ovarian response, and success rate between two groups of patients undergoing GIFT procedures and treated with the same stimulatory protocol but with a different timing in the administration of the gonadotropin hormone-releasing hormone analogue (GnRH-a). The former underwent a concomitant administration of gonadotropin and analogue; the latter started stimulation only after the achievement of complete hypogonadotropinism. The analogue was always given intranasally and stimulation was identical in the two groups. Our results showed that (1) prevention of premature luteinization is obtained with both approaches and (2) no significant difference in terms of length of stimulation, gonadotropin doses, ovarian response, and success rate was recorded between the two groups.

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A patient with post-operative recurrent parathyroid adenoma was treated with percutaneous injection of absolute ethanol under ultrasonographic guidance. Serum calcium and PTH level were both successfully normalized, while recurrent nerve palsy was encountered as side effect. Six months later, she was suffered from hyperparathyroidism again, because of local tumor recurrence. Her recurrent nerve palsy was cured at that time. This technic could be a simple and non-invasive alternative for the conventional surgical procedure, but the indication for larger adenomas like this case should be carefully considered.

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The hypothalamic pituitary axis was studied in patients with an abnormal pattern of gonadotropin release during chronic treatment with LH-RH agonist. Two patients had PCOD and the third demonstrated the early luteinization phenomenon. Following a well-defined gonadotropin rise with initiation of LH-RH treatment, no further response was noted. Stabilization of the LH:FSH ratio in PCOD patients was noted after 4 weeks of treatment. Administration of both native LH-RH (100 micrograms) and intravenous pulsatile LH-RH did not evoke any rise in LH. In addition to the above LH-RH challenges, the positive feedback was examined by administration of estradiol benzoate (EB). The study demonstrated that, although the pituitary did not respond to any LH-RH challenge, it may still respond by a rise in LH following EB administration. Both functions of the hypothalamic pituitary axis should be examined in order to determine the state of medical hypophysectomy.

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Studies concerning variations of the central renin-angiotensin system (RAS) during immobilization stress in rats have shown a significant increase in renin-like activity in the hypothalamus and fronto-parietal cortex, together with a definite decrease in the hypophysis and pineal gland. The resultant stress analgesia is blocked by the previous administration of naloxone and saralasin (angiotensin II antagonist). The intracerebral administration of renin and angiotensin II produces an increase in latencies to thermoalgesic stimuli; this is reduced, as is immobilization stress, by naloxone and saralasin. Both chemical hypophysectomy obtained by dexamethasone pretreatment as well as surgical epiphysectomy block the stress-induced analgesia. The experimental data obtained argue in favour of the participation of the cerebral RAS in stress analgesia through the indirect mechanism of release of opioid peptides.

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Pain is one of the most feared consequences of cancer. Control of pain from cancer should be possible with the approaches discussed above. Changing attitudes toward the effective use of narcotic analgesics, the development of novel routes and methods of administration, and a clinical approach based on scientific principles and humane care offer the promise of improved management of pain in patients with cancer.

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