The effect of 5-lipoxygenase inhibition on blood-brain barrier permeability in experimental brain tumors.

To determine if leukotrienes are important mediators of vascular permeability in brain tumors, the effect of 5-lipoxygenase inhibitors on blood-tumor barrier permeability in rats harboring HK Walker 256 brain tumors was examined using quantitative autoradiography with alpha-14C-aminoisobutyric acid. The 5-lipoxygenase enzyme converts arachidonic acid to leukotrienes. Three 5-lipoxygenase inhibitors were utilized: BW755C, nordihydroguaiaretic acid, and AA-861. All three 5-lipoxygenase inhibitors significantly decreased vascular permeability both within the tumors and in brain adjacent to tumor. This suggests that capillary permeability in and adjacent to tumors is influenced by endogenous leukotrienes and that leukotrienes play an important role in brain tumor edema.     

Plasminogen activators and plasminogen activator inhibitor 1 before and after venous occlusion of the upper limb in thromboangiitis obliterans (Buerger's disease).

Plasma levels of plasminogen activators (t-PA, u-PA) and their inhibitor (PAI-1) were studied in patients suffering from Buerger's disease and healthy volunteers before and after 15 minutes of venous occlusion test. The baseline levels of t-PA in group of patients did not differ from those of controls. On the contrary patients with Burger's disease showed a marked increase in u-PA antigen concentrations with concomitant decrease in PAI-1 antigen levels. During venous stasis t-PA antigen concentrations increased in all subjects, however it was much pronounced in controls. Venous occlusion resulted in significant decrease in free PAI-1 levels in the group of patients only. In conclusion, Buerger's disease is associated with the endothelial derangement with increased u-PA release and decreased PAI-1 release, which does not influence the function of fibrinolytic system. The fact that the reduced response of the endothelium to release t-PA after venous stasis goes in parallel with marked decrease in PAI-1 antigen levels seems to suggest that patients suffering from Buerger's disease are not at high risk of intravascular fibrin deposition.     

Tubulo-interstitial nephritis (TIN) with no glomerular lesions, distal renal tubular acidosis and asteatosis cutis in a patient with systemic lupus erythematosus (SLE): a case report]

We report a 28-year-old woman with systemic lupus erythematosus (SLE) who showed tubulo-interstitial nephritis (TIN) without any glomerular changes. In 1990, she was admitted to our hospital, complaining of anorexia, vomiting and persistent high fever. Laboratory findings showed proteinuria, pancytopenia, hypocomplementemia and positive for antinuclear antibody, anti-DNA antibody, anti-Sm antibody, anti-SSA antibody and anti-SSB antibody. We made a diagnosis of SLE. Furthermore, distal renal tubular acidosis and asteatosis cutis were revealed. The diagnosis of Sj?gren's syndrome was not made. We treated with high-dose prednisolone (60mg/day) and achieved improvement of symptoms and laboratory data. Open renal biopsy showed TIN without any glomerular changes. Predominant TIN is very rare in SLE. We discussed its pathogenesis and relation to the renal lesions of Sj?gren's syndrome.     

Accessory nerve neurotization in infants with brachial plexus birth palsy

We report the surgical results of 13 accessory nerve neurotizations in brachial plexus birth palsy. The mean age at operation was 5.9 months. The accessory nerve was transferred to three C5 roots, to three C6 roots, to four posterior division of the middle trunks, to one musculocutaneous nerve, and to two suprascapular nerves. Sixty-seven percent of the cases acquired M4 or more in the deltoid muscle, 88% in the infraspinatus muscle, and 100% in the biceps brachii muscle. Twenty-five percent of the cases acquired M4 or more in the triceps brachii muscle and the wrist extensor muscles. These results were much better than formerly reported for adult cases by other authors. No functional compromise of the trapezius muscle was noted. The accessory nerve neurotization can be used safely and effectively in neurosurgical reconstruction of the brachial plexus palsy in infants. © 1994 Wiley-Liss, Inc.     

Technique of intramedullary fixation for arthrodesis of the wrist in rheumatoid arthritis.

We did 18 arthrodeses of the wrist in 16 patients with rheumatoid arthritis using an intramedullary fixation technique. There were 15 women and one man, whose ages at operation ranged from 47 to 71 years (mean 58). Follow up ranged from 13 to 68 months (mean 27). The operative technique consists of a combination of intramedullary placement of two Kirschner (K)-wires and an autogenous bone graft. At follow up bony union was apparent in all cases. K-wires came out of the metacarpal joints in two cases. Paraesthesiae in the median nerve distribution occurred in two cases which both recovered within three months.     

Spontaneous mesenteric hemorrhage associated with ehlers-danlos syndrome

The vascular type of Ehlers-Danlos syndrome is a genetic disorder of connective tissue and is frequently associated with catastrophic arterial complications. Its surgical treatment is extremely difficult because of the fragility of vessels. This article describes three patients with vascular type of Ehlers-Danlos syndrome who developed mesenteric hemorrhage due to spontaneous arterial rupture. The clinical and molecular characteristics of the disease are briefly reviewed.     

Ketamine Suppresses Platelet Aggregation Possibly by Suppressed Inositol Triphosphate Formation and Subsequent Suppression of Cytosolic Calcium Increase

Background: Ketamine has been shown to suppress platelet aggregation, but its mechanisms of action have not been defined. The purpose of the current study is to clarify the effects of ketamine on human platelet aggregation and to elucidate the underlying mechanisms of its action.

Methods: Platelet aggregation was measured using an eight-channel aggregometer, and cytosolic free calcium concentration was measured in Fura-2/AM-loaded platelets using a fluorometer. Inositol 1,4,5-triphosphate (IP3) was measured with use of a commercially available IP3 assay kit. To estimate thromboxane A2 (TXA2) receptor binding affinity and expression, Scatchard analysis was performed using [3H]S145, a specific TXA2 receptor antagonist. TXA2 agonist binding assay was also performed. The membrane-bound guanosine 5'-triphosphatase activity was determined using [[gamma]-32P]guanosine triphosphate by liquid scintillation analyzer.

Results: Ketamine (500 [mu]m) suppressed aggregation induced by adenosine diphosphate (0.5 [mu]m), epinephrine (1 [mu]m), (+)-9,11-epithia-11,12-methano-TXA2 (STA2) (0.5 [mu]m), and thrombin (0.02 U/ml) to 39.1 +/- 30.9, 46.3 +/- 4.3, -2.0 +/- 16.8, and 86.6 +/- 1.4% of zero-control, respectively. Ketamine (250 [mu]m-1 mm) also suppressed thrombin- and STA2-induced cytosolic free calcium concentration increase dose dependently. Although ketamine (2 mm) had no effect on TXA2 receptor expression and its binding affinity, it (1 mm) suppressed intracellular peak IP3 concentrations induced by thrombin and STA2 from 6.60 +/- 1.82 and 4.39 +/- 2.41 to 2.41 +/- 0.98 and 1.90 +/- 0.86 pmol/109 platelets, respectively, and it suppressed guanosine triphosphate hydrolysis induced by thrombin (0.02 units/ml) and STA2 (0.5 [mu]m) to 50.3 +/- 3.2 and 67.5 +/- 5.5%versus zero-control, respectively.     

Report of a patient of primary Sj?gren syndrome, IgA nephropathy and chronic idiopathic thrombocytopenic purpura]

We describe the case of a 61-year-old woman diagnosed with primary Sj?gren's syndrome (SS) after an 8-year history of IgA nephropathy and a 3-year history of recurrent purpuric rashes. Her two daughters had previously been diagnosed with other autoimmune diseases. One daughter had Graves' disease and the other had Hashimoto's disease and systemic lupus erythematosus. The diagnosis of SS was made based on dryness of mucous membranes, Shirmer test, and parotid sialography. Thrombocytopenia, high platelet-aggregated IgG (PA-IgG) level, and normal megakaryocytes count in bone marrow suggested that her recurrent purpuric rashes were due to idiopathic thrombocytopenic purpura (ITP). Patients with SS may develop other autoimmune diseases. This case aids understanding of the immune pathogenesis and genetic background of SS.