Prolonged systemic and regional haemodynamic effects of intracerebroventricular angiotensin II in conscious sheep

1. The haemodynamic mechanisms by which infusion of angiotensin II (AngII), either into the lateral cerebral ventricles (i.c.v.) or intravenously (i.v.), increased arterial pressure were studied in conscious sheep. 2. Sheep were previously fitted with flow probes for measurement of cardiac output and coronary, mesenteric, renal and iliac blood flows. 3. Intracerebroventricular AngII (10 nmol/h for 1 h) increased arterial pressure by 11 +/- 4 mmHg (P < 0.001) due to vasoconstriction, predominantly in the mesentric vasculature. These effects developed over 30 min and took 2 h to return to control. Following the infusion renal conductance increased continuously for 3 h, resulting in a parallel increase in renal blood flow (to 75 +/- 18 mL/min above control, P < 0.001). 4. Intracerebroventricular AngII increased plasma vasopressin from 0.8 +/- 0.3 to 7.2 +/- 1.8 pg/mL (P, 0.01), and reduced plasma renin concentration from 0.9 +/- 0.3 to < 0.4 nmol/L/h. 5. The pressor effect of i.v. AngII (5, 10, 25, 50 nmol/h) also depended on peripheral vasoconstriction, but the pattern of responses was different. The greatest degree of vasoconstriction occurred in the renal, followed by the mesentric and iliac vascular beds; these effects were rapid in onset and offset. 6. In conclusion, the pressor responses to both i.c.v. and i.v. angiotensin depended on peripheral vasoconstriction, but there were contrasting regional haemodynamic changes. ICV AngII caused a prolonged pressor response, mainly due to mesentric vasoconstriction possibly partly due to vasopressin release, and following the infusion there was a pronounced, long-lasting renal vasodilatation. In contrast, i.v. AngII caused vasoconstriction preferentially in the renal vascular bed and its effects were short lasting.     

A novel antithrombin gene mutation: slippage and mispairing as a mechanism of genetic disease

Treatment options for acute leukemia relapsing after allogeneic BMT include conventional chemotherapy or a second transplant; however, results are rather discouraging, the first option being associated with poor survival and the second with a high mortality rate. More recently, donor leukocyte infusion (DLI) from the original donor has been used for relapsed patients in an attempt to induce a graft-versus-leukemia (GVL) effect. This procedure is partially devoid of the toxicity inherent to a second BMT. At our Institution, a 36-year-old patient with biphenotypic AML in second complete remission after relapse following allogeneic BMT was treated with peripheral blood stem cell (PBSC)-enriched donor leukocytes, obtained after in vivo priming with rhG-CSF. The patient experienced extensive cGVHD but developed a testicular relapse while in full hematologic remission. After irradiation of the sanctuary site he remains free of disease, still with chronic GVHD, 21 months after bone marrow relapse. This case suggests that immunologically privileged sites are inaccessible to GVHD/GVL effect. This should be considered when planning salvage transplants procedures in patients at risk for extramedullary involvement.     

Immune responses to canine distemper virus in joint diseases of dogs

Wearing-off phenomenon that complicates levodopa therapy of Parkinson's disease has been attributed to a reduction in striatal dopamine storage due to the progressive degeneration of presynaptic dopaminergic terminals. To determine whether postsynaptic mechanisms also contribute to these response fluctuations, the duration of the antiparkinsonian response in parkinsonian patients grouped by disease severity was compared following discontinuation of a steady-state optimal-dose infusion of apomorphine. Although the plasma half-life of this dopamine receptor agonist remained constant, its mean efficacy half-time declined from 66 minutes in early, levodopa-naive patients to 33 minutes in advanced, complicated parkinsonians (p < 0.005). Since the motor effects of apomorphine do not depend on the presence of dopaminergic terminals, changes at the postsynaptic level undoubtedly contribute to the diminished response duration. The only slightly greater attenuation of levodopa's motor effects observed previously under similar conditions suggests these postjunctional alterations, possibly involving relatively plastic striatal dopaminoceptive systems, account for most of the shortening in the duration of levodopa action that underlie wearing-off fluctuations.     

Why are we here at the clinic? Parent–child (dis)agreement on referral problems at outpatient treatment entry.

Do clinic-referred children and their parents agree on the problems for which treatment is undertaken? The authors asked 381 outpatient-clinic-referred children and their parents to list, independently, the child's target problems. Of the parent-child pairs, 63 % failed to agree on even a single problem. When problems were grouped into broad categories (e.g., delinquent, withdrawn), more than a third of the pairs still failed to agree on a single broad problem area. Parent-child agreement was higher for externalizing than for internalizing problem categories (though poor for both). Low parent-child agreement may help explain the poor outcomes often reported for clinic-based child therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of ICV infusion of CRF on blood pressure and adrenal steroids in rabbits

The effect of prolonged, 22 h long, intracerebroventricular (i.c.v.) infusion of corticotropin-releasing hormone (CRF) on plasma cortisol, corticosterone and electrolyte concentrations, mean arterial blood pressure (MAP) and heart rate (HR) were investigated in conscious rabbits. During i.c.v. infusion of CRF, 1 and 3 micrograms/h, at a rate of 17 microliters/h, plasma cortisol and corticosterone concentrations rose to the level noted after ACTH stimulation in rabbits. Plasma [Na] did not change, but plasma [K] was reduced and plasma osmolality increased during the infusion of CRF, 3 micrograms/h. MAP and HR, recorded continuously during i.c.v. infusion of CRF, changed only with the higher dose of CRF: MAP was elevated during the first 5 h of infusion, and then returned to the control level. HR was lower than control at the end of the first hour of infusion and again between 9 and 15 h of infusion. The prolonged rise of CRF concentration in the brain induced a sustained rise in circulating adrenal steroid hormones. MAP did not increase to the level noted after bolus i.c.v. injection of CRF and the rise in MAP was not sustained.     

Critical thickness of GaAs/InGaAs and AlGaAs/GaAsP strained quantum wells grown by organometallic chemical vapor deposition

In this paper we describe a study of strained quantum wells (QWs) as a means to experimentally observe the critical thickness (h _c) for the formation of interfacial misfit dislocations. Two material systems were investigated: GaAs/In_0.11Ga_0.89As, in which the QW layers are under biaxialcompression, and Al_0.35Ga_0.65As/GaAs_0.82P_0.18, in which the QW layers are under biaxialtension. Samples were grown by atmospheric pressure organometallic chemical vapor deposition, and characterized by low-temperature photoluminescence (PL), x-ray diffraction, optical microscopy, and Hall measurements. For both material systems, the observed onset of dislocation formation agrees well with the force-balance model assuming a double-kink mechanism. However, overall results indicate that the relaxation is inhomogeneous. Annealing at 800–850° C had no significant effect on the PL spectra, signifying that even layers that have exceededh _c and have undergone partial relaxation are thermodynamically stable against further dislocation propagation.     

Complications of cardiac hydatid cyst. 2 cases

BACKGROUND: Cardiac localization of hydatiosis is uncommon, involving 0.5 to 2% of all cases. CASE REPORTS: The first patient was a 15 year old adolescent whose cardiac hydatidosis was revealed by tamponade. The second case was discovered in a 28-year-old woman without cardiac signs who was explored for allergy manifestations with fever, urticaria and joint point. Both patients underwent surgery. Eighteen months after the operation, the second patient developed hemiplegia leading to the discovery of multi-organ localizations (brain, spleen, kidney) which were not evidenced at the initial work-up. The neurological deficit and brain cysts regress with albendazole treatment. DISCUSSION: The risk of rupture of the cardiac hydatic cyst requires rapid surgical cure. Medical treatments are discussed. Anti-hydatic drugs can be used alone in case of a contraindication for surgery. In other patients they are given during the perioperatie period and for a prolonged period after surgery.