ABSTRACT
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.
Subject(s)
Chromatography, Gas/methods , Hydrocarbons, Chlorinated/analysis , Hypophysectomy, Chemical/methods , Water Pollutants, Chemical/analysis , Electrons , Gas Chromatography-Mass Spectrometry/methods , Hypophysectomy, Chemical/instrumentation , Membranes, Artificial , VolatilizationABSTRACT
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
Subject(s)
Humans , Breast Neoplasms/therapy , Hypophysectomy, Chemical/methods , Prostatic Neoplasms/therapy , Neoplasm Metastasis , Pain/therapy , Hypophysectomy, Chemical/adverse effects , Time Factors , Treatment OutcomeABSTRACT
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.
Subject(s)
Cushing Syndrome/surgery , Hypophysectomy, Chemical/adverse effects , Hypophysectomy/adverse effects , Pulmonary Embolism/etiology , 17-Hydroxycorticosteroids/urine , Adult , Cushing Syndrome/blood , Cushing Syndrome/urine , Female , Humans , Hydrocortisone/blood , Hydrocortisone/urine , Hypophysectomy, Chemical/methods , Pulmonary Embolism/blood , Pulmonary Embolism/urineABSTRACT
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.
Subject(s)
Buserelin/administration & dosage , Gonadotropin-Releasing Hormone/analogs & derivatives , Hypophysectomy, Chemical/methods , Hypophysectomy/methods , Infertility, Female/therapy , Luteolytic Agents/administration & dosage , Polycystic Ovary Syndrome/therapy , Administration, Intranasal , Drug Administration Schedule , Female , Follicle Stimulating Hormone/blood , Gonadotropin-Releasing Hormone/administration & dosage , Humans , Infertility, Female/blood , Injections, Subcutaneous , Luteinizing Hormone/blood , Polycystic Ovary Syndrome/blood , Triptorelin PamoateABSTRACT
The technique is of interest in deep bone pain in terminal metastasized cancer, but early relapses often occur. The hypoalgesia or analgesia obtained does not seem to result from endocrine mechanisms only, nor from the release of endogeneous opioid peptides. This neuroadenolysis seems to interfere in the pain pattern either through still unknown neurotransmitters, or through the dissociation of fibers transmitting pain to the floor of the diencephalon.
