Cyclosporine A inhibition of microcystin toxins

Cyclosporine A (CyA) given i.v. at a dose of 1.25 mg/mouse blocks a subsequent i.v. lethal dose (1.7-1.8 x LD50) of microcystin-LR for 24 hr, and is about 50% protective at 48 hr. Conversely, the fraction of mice that can be rescued by CyA (0.2 mg/mouse) after a lethal dose of microcystin-LR decreases rapidly with a pharmacodynamic half-time of only about 100 sec. The prophylactic action of CyA was tested against lethal doses of four microcystins. The acute lethality of 1.7-1.8 x LD50 dose of microcystin-LR, -RR, -LY, or -LA given 1 hr after administration of 0.2 mg of CyA is 0%, 0%, 58%, or 100%, respectively. Even a 0.6 mg/mouse dose of CyA is ineffective prophylaxis against a lethal dose of microcystin-LA. The inhibitory potency of CyA on microcystin toxicity can be completely reversed by the single L-amino acid substitution of alanine for arginine in the microcystin.     

Schultz metacarpophalangeal arthroplasty: a long-term follow-up study

We describe a prospective, long-term evaluation of the Schultz metacarpophalangeal joint implant. The prosthesis is a semiconstrained, cemented implant with a ball-in-socket articulation. Thirty-six implants were followed for an average of 10.9 years. There was a progressive decrease in range of motion and strength and a recurrence of ulnar deviation. The neck of the proximal phalangeal component fractured in 39% of the joints. Periarticular heterotopic bone formed in all joints, but was extensive in only 22%. Although some lucency of the bone-cement interface was seen in 80% of the joints, no prosthetic loosening occurred in this series. Our results indicate that long-term, intramedullary cement fixation of relatively long-stemmed components can be satisfactory. However, the articulated portion of this implant does not consistently withstand the stresses transmitted across the joint and does not provide long-term joint stability.     

Mode of onset of simple phobia subtypes: further evidence of heterogeneity

Previous research has demonstrated heterogeneity of the simple phobia diagnostic category. As a further test of the notion of heterogeneity of the DSM-III-R simple phobia diagnostic category, mode of onset was examined in a sample of simple phobic outpatients. Patients were separated into one of four subtypes: animal or insect, blood and injury, situational, and choking-vomit phobias. Careful study yielded five distinct mode-of-onset categories. Two researchers independently determined the mode of onset for the patients studied: direct trauma, spontaneous, vicarious learning, gradual, and lifelong. Significant mode of onset differences were observed across groups. Situational phobics reported a preponderance of spontaneous onsets as compared to the other groups studied. These results offer further evidence of the heterogeneity of the simple phobia diagnostic category and also support the contention that situational simple phobias are closely related to agoraphobia.     

Use of sterile gloves in the management of sutured hand wounds in the A&E department

In a single-blind, controlled, prospective trial of 242 sutured wounds of the hand in the A&E department there was increased late purulent infection in those treated without gloves. This difference is statistically significant. We recommend wearing of sterile gloves to suture all wounds in A&E departments.     

Effect of the calcium antagonist nimodipine on hemodynamics, gas exchange and endocrine parameters in opiate anesthesia

During opiate anesthesia (standardized dosage of fentanyl) for operation of cerebral aneurysms after subarachnoid hemorrhage, different hemodynamic, respiratory, metabolic, and endocrine parameters were determined before (1 in Fig. 1-4), after (6), and during consecutive stages of induced hypotension (systolic blood pressure 100 mmHg (2), 90 mmHg (3), 80 mmHg (4, 5) during an interval of 20 min), comparing two groups with different vasodilating drugs. In the first group (nimo/NNP in Figs. 2-4) a constant infusion of nimodipine was applied (1.2 micrograms/kg b.w. X min-1), while sodium nitroprusside (NNP) was added in small amounts as necessary to achieve the respective values of systolic blood pressure. In the second group (NNP in Figs. 2-4) induced hypotension was done with NNP alone (maximal dosage: 8 micrograms/kg X min-1). Each group consisted of 11 patients. Additional nimodipine (in the first group), a calcium antagonist commonly recommended for preventing vasospasm and consequent neurologic deficits after subarachnoid hemorrhage, not only reduced the need for NNP, a vasodilating drug with potential toxicity, by 70%-80% as compared to the second group (Table 1). In addition, the cardiovascular situation was more stable in patients with nimodipine infusion: rapid variations of blood pressure and heart rate as well as tachyphylaxis and rebound, typical for NNP-induced hypotension, were avoided. Nevertheless, comparing the hemodynamic data at fixed stages of hypotension, there were only minor differences between both groups (Fig. 2). Reduction of blood pressure was due to a decrease in vascular resistance and was accompanied by an increase in cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)