Effect of hydrostatic pressure on ADH induced osmotic water flow in toad bladder

The effect of hydrostatic pressure (HP) on antidiuretic hormone (ADH) stimulated osmotic water flow (Jv) across the toad urinary bladder was evaluated. Jv for ADH-stimulated bladders was significantly reduced by an elevation of the serosal HP gradient to 1 cm H₂O. Subsequent elimination of the HP gradient resulted in a recovery of Jv. Serosal HP also caused a reversible increase in sucrose permeability (P sucrose). For ADH-treated bladders fixed with glutaraldehyde during serosal HP exposure, subsequent exposure to a mucosal or serosal HP gradient caused acceleration or inhibition of Jv, respectively. The reduction in ADH-associated Jv with serosal HP was apparently caused by a back-flux of water through a paracellular pathway. Jv and P sucrose were not affected by mucosal HP during ADH stimulation. The results suggest a specific sensitivity of a paracellular pathway to a small serosal HP gradient in bladders with ADH-stimulated water flow. The reversibility of this effect on P sucrose suggests that the elements comprising the apical junctions are dynamic structures capable of recovering at least some of their permeability properties.     

Specific ultrarush desensitization in Hymenoptera venom-allergic patients.

BACKGROUND: Hymenoptera venom hypersensitivity is an epidemiologically important problem. The only effective treatment in the management of venom-allergic patients with a history of generalized reactions to insect sting is specific immunotherapy. OBJECTIVE: To demonstrate safety and effectiveness of a modified ultrarush desensitization protocol in venom-allergic patients. METHODS: Fifty-seven patients with Hymenoptera venom allergy underwent a specific 1-day ultrarush desensitization by the subcutaneous route, reaching the cumulative dose of 101.1 microg in 2.5 hours. The maintenance dose (100 microg) was administered after 15 days and thereafter once a month. Patients were followed up for a year. Antihistamines were withheld for 15 days before and during desensitization to not underestimate the incidence of adverse effects. RESULTS: All patients but I completed the ultrarush desensitization. (This patient discontinued the treatment because of a hypertensive crisis not related to the desensitization.) The treatment caused a rapid variation of immunological parameters (IgE, IgG4) since the 15th day. After the desensitization, skin prick test results became negative in 15 patients (27%, decrease of 3.5 log), whereas they decreased in 14 patients (25%, decrease of 1 log). Sixty-four percent showed no adverse effects. Only 7% had a mild systemic reaction. CONCLUSIONS: Ultrarush desensitization is an effective and safe therapy in the management of patients with Hymenoptera venom allergy. In fact, it provides a faster tolerance, without significant differences regarding incidence of severe adverse effects, compared with traditional and rush protocols. It can be adopted for all patients, even children and teenagers.     

Sequential convective therapies (SCT): a prospective study on feasibility, safety, adequacy and tolerance of on-line hemofiltration and hemodiafiltration in sequence

Sequential dialysis techniques (i.e pure ultrafiltration followed by dialysis) have been used in the past, due to their capability to remove large volumes of fluids without inducing hemodynamic instability. The disadvantages of inadequate efficiency and lack of technology lead to the decline of such methods. Hemofiltration (HF) and hemodiafiltration (HDF) are recently being utilized in a greater proportion thanks to on-line fluid preparation systems. Each process (HF and HDF) has its own benefits in the removal of small, medium and high-molecular weight substances and in hemodynamic stability. Sequential convective therapies (SCT) such as hemofiltration-hemodiafiltration in sequence (HF-HDF) may combine the benefits and eliminate the disadvantages of each method and should be studied in order to explore their potential application in modern dialysis. Furthermore they can be easily applied nowadays, due to the development of new sophisticated dialysis machines. In order to evaluate the feasibility, safety, efficiency and tolerance of different SCT methods we studied 3 schedules: SCT1: 1h pre-dilution HF followed by 3h of post-dilution HDF (in the HF mode we lost 25% of the total fluid that had to be removed). SCT2: 1h pre-dilution HF followed by 3h of post-dilution HDF (in the HF mode we lost 50% of the total fluid that had to be removed). SCT3: 2h pre-dilution HF followed by 2h of post-dilution HDF (in the HF mode we lost 50% of the total fluid that had to be removed). We studied 6 chronic hemodialysis patients using the same machine (AK200 ULTRA), with on-line fluid preparation system and the same type of dialyzer (Polyflux 210). SCT schedules were compared to on-line HF, on-line HDF and high flux dialysis performed with the same dialyzers. The treatments resulted safe, easy, feasible and well tolerated with an improved hemodynamic response to high volume convective therapies. Adequacy of treatment was satisfactory in all SCT schedules while middle molecular weight solute clearance and removal resulted higher in treatments with higher convective component. SCT might represent an interesting option for the future especially in patients with hemodynamic instability and requirements for interventions during treatment.     

Light reflection rheography and thoracic outlet syndrome

The authors have studied with a light reflection rheograph (LRR) 112 cases: 54 patients with suspected "thoracic outlet syndrome" (TOS) in the functional phase, 28 patients with phlebothrombosis localized in upper limbs, and a control group of 30 healthy subjects to evaluate the upper limbs' venous outlet. They recorded a good correlation among results obtained with LRR, clinical examination, Doppler, and phlebographic examination. The data obtained lead them to propose this methodology as an important examination in the evaluation of upper thoracic pathology.     

Laryngopyocele: three new clinical cases and review of the literature

Laryngopyocele is a fairly rare disease. It is a complication of laryngocele. Its clinical picture is often alarming; thus it needs fast differential diagnosis. Computed tomography allows early diagnosis. Surgical treatment permits a complete recovery. An association between laryngocele and carcinoma of the larynx has been reported by some authors. Three new cases of laryngopyocele are presented and discussed. Received: 23 November 1999 / Accepted: 29 May 2000