Electrically stimulated Krebs-Henseleit buffer does not relax precontracted human bronchiin vitro

Electric field stimulation (EFS) causes a non-adrenergic relaxation of precontracted human airways. Only 10–20% of this response can be blocked with the nervous conductance blocker tetrodotoxin (TTX). Therefore, 80–90% of the non-adrenergic relaxation is not neurally mediated. The mechanism of this non-neural component is unclear. We examined whether EFS induces the generation of muscle relaxing substances in oxygenated Krebs-Henseleit buffer. Strips of central airways of 6 patients were precontracted with methacholine (10^–5 M) and exposed to Krebs buffer that had previously been stimulated with EFS (50 V, 0.3 ms, 30 s, 1–50 Hz). Results were compared to those obtained with unstimulated buffer. The contractile state of the airways did not change significantly with either EFS-stimulated or unstimulated buffer. We conclude that in oxygenated Krebs buffer EFS does not cause generation of substances that change the contractile state of prestimulated human airways.     

Effects of zymosan-activated human granulocytes on isolated human airways

In asthma a temporal association exists between the late allergic reaction (LAR), the influx of granulocytes into the airway wall, and an increase in bronchial responsiveness. We therefore tested the hypothesis that activated human granulocytes constrict isolated human airways and increase their sensitivity to cholinergic stimuli. Bronchial rings were dissected from 23 lung tissue specimens collected at thoracotomy and studied isotonically in organ baths. Airways were incubated with 1, 2, 5, 10, or 20 x 10(6) granulocytes from normal or atopic donors. Activation of the cells with serum-treated zymosan (STZ, 0.2 mg/ml), which itself did not alter baseline airway caliber, resulted in a bronchoconstriction proportional to the number of zymosan-activated granulocytes (ZAG) present (rs = 0.79, p less than 0.001). This contraction was reduced by about 70% with the leukotriene C4/D4 receptor antagonist FPL 55712 (11.5 microM; p less than 0.001) or with the lipoxygenase inhibitor nordihydroguaiaretic acid (10 microM; p less than 0.001). The scavengers of activated oxygen molecules superoxide dismutase (300 U/ml) and bovine catalase (5,000 U/ml), the cyclooxygenase inhibitor indomethacin (10 microM), or the histamine (H1) receptor antagonist mepyramine (2.8 microM) had no effect. Granulocyte suspensions from atopic donors contained more eosinophils (p less than 0.001), and the magnitude of the contraction to 10 x 10(6) ZAG was related to the proportion of eosinophils (rs = 0.66, p less than 0.01). The sensitivity of the airways to methacholine was unchanged in the presence of 1, 2, or 5 x 10(6) ZAG and decreased with 10 or 20 x 10(6) ZAG (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Point Seroprevalence Survey of Ehrlichia ruminantium Infection in Small Ruminants in The Gambia

Using the MAP1-B enzyme-linked immunosorbent assay, we tested 1,318 serum samples collected from sheep and goats at 28 sites in the five divisions of The Gambia to determine the Ehrlichia ruminantium seroprevalence rates and to assess the risk for heartwater. About half (51.6%) of 639 sheep were positive, with seroprevalence rates per site varying between 6.9% and 100%. The highest seroprevalence was detected in the western part of the country (88.1% in the Western Division and 62.1% in the Lower River Division). Sheep in the two easterly divisions (Central River and Upper River divisions) showed the lowest seroprevalence of 29.3% and 32.4%, respectively, while those in the North Bank Division showed an intermediate prevalence of 40.6%. In goats, less than one-third (30.3%) of 679 animals tested were positive. The highest seroprevalence was detected in goats in the North Bank Division (59%) and Western Division (44.1%). Goats in the Lower River Division showed an intermediate level of 21.9%, whereas the lowest rates were found in the eastern part of the country (4.8% in the Central River Division and 2.3% in the Upper River Division). At nearly all sites, seroprevalence rates were higher in sheep than in goats. The results show a gradient of increasing heartwater risk for susceptible small ruminants from the east to the west of The Gambia. These findings need to be taken into consideration when future livestock-upgrading programs are implemented.     

Changes in plasma glucose,free fatty acids (FFA), cortisol,immunoreactive human growth hormone (IRHGH) and immunoreactive insulin (IRI) after tolbutamide-induced hypoglycemia in obese subjects

Summary The investigation was carried out on 30 subjects: 21 obese subjects and 9 normal weight controls. Twelve of the obese subjects and the 9 controls received 1 g tolbutamide i.v.; the other 9 obese subjects received 1.5 g tolbutamide, all in fasting condition. Plasma glucose, FFA, cortisol, serum IRI, and IRHGH were measured before and 15, 30, 60, 90 and 120 min after tolbutamide administration. A blunted response of cortisol and IRHGH to the hypoglycemic stimulus was observed in obese subjects receiving 1 g tolbutamide. The blunted response was reversed when 1.5 g tolbutamide was injected. Glucose levels were significantly higher at 60 min in the obese who received 1 g tolbutamide as compared to the controls, and were significantly lower 30, 60 and 90 min after the tolbutamide injection in obese who received 1.5 g tolbutamide. FFA showed significantly higher values 90 and 120 min after the injection in both groups of obese subjects: dose dependency was not observed. Insulin values were significantly higher 15 min after tolbutamide injection in the obese receiving 1.5 g tolbutamide when compared to those receiving 1 g and to the controls. The blunted plasma cortisol and serum IRHGH responses were reversed when larger doses were used. Some possible explanations for the results are discussed: a hypothalamo-pituitary underresponsiveness, a lower ratio of biologically active versus biologically unactive IRI, and peripheric insulin resistance in obesity.     

Effect of epithelial denudation, inflammatory mediators and mast cell activation on the sensitivity of isolated human airways to methacholine.

In asthmatics, both the continuous release of mast cell-derived inflammatory mediators and damage of the airway epithelium may be related to the degree of bronchial responsiveness. We therefore evaluated the effect of inflammatory mediators and mast cell activation on the cholinergic responsiveness of strips of human bronchioles with and without epithelium. Cumulative concentration-response curves to methacholine were generated from strips with or without epithelium before, during and after incubation with threshold doses of either methacholine (3 x 10(-7) M, controls), histamine (3 x 10(-7) M), the thromboxane A2 analogue, U46619 (10(-9) M), prostaglandin (PG) D2 (3 x 10(-7) M), PGF2 alpha (3 x 10(-7) M), leukotriene (LT) C4 (10(-9) M), or anti-human immunoglobulin E (24.4 +/- 4.0 micrograms.ml-1). Strips without epithelium were 1.6 times more sensitive to methacholine than strips with epithelium (-log EC50:5.76 +/- 0.04 vs. 5.97 +/- 0.04, P less than 0.0001). The average contraction in response to identical doses of anti-IgE in strips without epithelium was 3 times greater than the contraction in strips with epithelium (P less than 0.05). Threshold concentrations of histamine, U44619 and PGD2 caused a similar non-parallel leftward shift of the concentration-response curve of strips with or without epithelium to methacholine (P less than 0.05). Together, epithelial denudation and low levels of mediators caused a 4.0- to 9.1-fold increase in sensitivity based on the -log EC10 and a 1.8- to 3.0-fold increase in sensitivity based on the -log EC50.(ABSTRACT TRUNCATED AT 250 WORDS)     

Facial cutaneous fistula due to a foreign body in Wharton's duct

An extremely rare case of a cutaneous fistula of the submandibular salivary gland is presented. The etiology of the fistula was a foreign body in Wharton's duct. We describe the clinical course, management and histo-pathological findings.     

Surgical possibilities in the third portion of the vertebral artery (above C2). Anatomical study and report of a case of anastomosis between subclavian artery and vertebral artery at C1-C2 level.

A reappraisal of surgical possibilities in the third portion of the vertebral artery (VA) above C2, has been done from an anatomical study on twenty autopsy specimens. A route passing between the internal jugular vein and the Sterno-cleido-mastoid muscle allows a simple approach to the transverse process of C1. After division of two muscles attached to this process, 1.5 cm of the VA can be exposed. For larger exposure of the artery, the foramen transversarium of C1 must be unroofed and the artery dissected in the guttering of the posterior arch of the atlas. This surgical route was used in a case of aneurysmal dysplasia at the C3 level. An anastomosis between the subclavian artery and VA at the C1-C2 level was performed with an autologous saphenous vein graft. The key points are the highest possible freeing of the XI nerve and the head position. Rotation and extension move the transverse process and the posterior arch of the atlas superficially and anteriorly.     

Non-A, Non-B Hepatitis in Hemophilic Patients with Inhibitor Treated with Activated Prothrombin Complex Concentrates: Lack of Correlation with an Antigen Possibly Related to Non-A, Non-B Hepatitis

A population of 30 severe hemophilia-A patients with antibodies to factor VIII, treated with Autoplex since 1980, experienced a 30% incidence of non-A, non-B (NANB) hepatitis. 8 of the 9 patients affected had clinical signs of hepatitis and 7 had ALT levels in excess of 200 IU/l; the mean incubation time was 13 days. Only 5 of the 26 lots of Autoplex used were possibly transmitting the infective agent. An ELISA test to detect an antigen (DS-Ag) possibly related to NANB hepatitis was used to screen hemophilia-A and B patients. Its incidence was lower in patients treated less than 5 times a year (7.9%) than in patients treated over 15 times a year (25-27%) with locally prepared blood derivatives. Following treatment with Autoplex, the incidence of DS-Ag in inhibitor patients increased significantly (50%). In this last population, DS-Ag was shown to be unrelated to the NANB hepatitis observed. Although no direct evidence could be given, Autoplex was likely to transmit both the agent responsible for short incubation NANB hepatitis and DS-Ag.