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Notizen: Abstract: The lateral hypothalamus has an important role in regulating food and water intake. We have investigated the endogenous release of monoamines from the lateral hypothalamus during manipulations of plasma osmolality and circulating volume. Adult male Sprague-Dawley rats implanted with carbon paste in vivo electrochemical (EC) electrodes in the lateral hypothalamus were placed on a 72-h water deprivation schedule. Although the carbon paste EC electrode has an intrinsically ambiguous signal in which changes in ascorbic acid may appear as changes in catechol concentrations, pharmacologic studies in lateral hypothalamus indicated that the electrode most likely measured nor-epinephrine and possibly epinephrine. On the test day, the EC electrodes were scanned with linear sweep voltammetry from -0.2 to +0.4 V at a rate of 5 mV/s. Semiderivative signal processing showed catechol and hydroxyindole peaks at +0.11 and +0.23 V, respectively. Baseline recordings were made prior to rats drinking distilled water, 10% sucrose, 5% dextrose, 0.30% NaCl, 0.90% NaCl, or 10%D-mannitol. To control for the act of drinking, other implanted dehydrated rats were intraperitoneally injected with 5% dextrose, 0.30% NaCl, or 0.90% NaCl. To dissociate the effects of osmolality and circulating volume on the EC response, hydrated rats implanted with EC electrodes were subcutaneously injected with 12% NaCl or intraperitoneally injected with 35% polyethylene glycol. Other rats subjected to water deprivation and osmotic challenges were decapitated and trunk blood was collected for measurements of plasma osmolality and hematocrit. Similar experiments were conducted using homozygous Brattleboro rats which lack arginine vasopressin (AVP) but which preserve normal plasma osmolality with prodigious drinking. The use of these rats provided a way to dissociate monoamine changes related to AVP release from changes related to plasma osmolality. Results in Sprague-Dawley and Brattleboro rats showed that the EC catechol signal was lower in rats with high plasma osmolality and rose with drinking or intraperitoneal fluid administration as a direct function of the fall in plasma osmolality. Manipulations of plasma osmolality had a greater effect on the EC catechol signal than did manipulations of circulating volume. Thus, we conclude that changes in extracellular fluid catechol concentrations in the lateral hypothalamus linearly reflect changes in plasma osmolality.

Notizen: Objective To test the hypotheses:〈list xml:id="l1" style="custom"〉1that HIV infection predisposes to cervical intraepithelial neoplasia (CIN);2that this CIN is a result of HIV related immunosuppression; and3that this CIN is a result of immunosuppression causing increased expression of the potentially oncogenic viruses, human papilloma virus (HPV), Epstein Barr virus (EBV) and herpes simplex virus (HSV).Design A matched cross sectional study.Setting The Department of Gynaecological Oncology, The Samaritan Hospital, London; the Department of Genitourinary Medicine, St Mary's Hospital, London; and the Family Planning Clinic, Claremont Terrace, Glasgow.Subjects Fifty HIV seropositive women enrolled from the Genitourinary Medicine Department and the Drug Dependency Unit at St Mary's Hospital, London, and the Unit of Infectious Diseases at Ruchill Hospital, Glasgow. Forty-three HIV seronegative controls enrolled from the Department of Genitourinary Medicine at St Mary's Hospital, matched against 43 of the seropositive women for age, age at first intercourse, lifetime number of sexual partners, and smoking habit.Main outcome measures Associations between CIN, as detected by cytology and histology, and HIV infection. Association was also sought between CIN and immunosuppression, as measured clinically by T4 cell number, β-2-microglobulin and p24 antigen. Associations of these with: (1) HPV, as detected by Southern blot testing and the polymerase chain reaction; (2) EBV, as detected by Southern blot testing; and (3) HSV, as detected by tissue culture of endocervical swabs, was also studied.Results There was no significant difference in the prevalence of CIN or oncogenic viruses between HIV seropositive and seronegative women in the absence of immunosuppression. If the HIV infected women showed signs of immunosuppression, the prevalence of CIN was increased. No association was shown between detection of HPV, EBV and HSV and immunosuppression or CIN.Conclusion HIV infection may only be associated with an increased risk of CIN when immunosuppression is present.

Notizen: Anaesthetists are often employed as medical escorts for patients undergoing international transfer by air ambulance. There is little published data on the types of patients being transferred and on the incidence of adverse events. We performed a retrospective review of the documentation of all air ambulance transfers performed by a single company over a 2-year period followed by a prospective assessment of all high-risk patients transferred over a 1-year period. Of 483 transfers identified, 47% were defined as high-risk and 20% were of patients receiving mechanical ventilation. In the prospective group, 28% of patients required pretransfer optimisation, 7% required a major therapeutic intervention during transfer and there was a major adverse event in 12% of transfers. There were two deaths during transport. These data support the recommendation that escorting personnel should be from an appropriate speciality, have reasonable seniority and be adequately trained and supervised.

Notizen: The chemotactic efficiency of macrophages isolated from the kidney of spot, Leiostomus xanthurus, and hogchoker, Trinectes maculatus. was determined in fish captured from the York River and the heavily polluted Elizabeth River (Virginia). Chemotactic activity was quantified in Boyden chambers using Escherichia coli as the chemotactic stimulus. Macrophage chemc-taxis was found to be markedly reduced in the Elizabeth River fish as compared to York River controls. Chemotactic migrations of macrophages at 90 min were 55% and 33% for control and experimental spot, respectively. Values for control and experimental hogchoker were 85% and 56%, respectively. The macrophage chemotactic activity of Elizabeth River fish returned to normal (spot, 56%; hogchoker, 80%) after the fish were held in clean water for 3 weeks. This indicates that the decreased chemotactic activity was related to exposure to Elizabeth River pollutants but may be reversible.