Experimental studies on auricular flutter and auricular fibrillation

Injection of aconitine into the region of the head of the sinus node causes auricular tachycardia with a rate between 200 and 400 per minute. Often auricular fibrillation appears spontaneously or follows vagus stimulation. The change of the auricular tachycardia into fibrillation and vice versa, which was ofter registered, shows that the auricular tachycardia is auricular flutter and not “paroxysmal auricular tachycardia”.Cooling of the focus of injection immediately abolishes the fibrillation which reappears when the cooling is interrupted. These results cannot be explained by the circus movement theory of Lewis. They can only be explained by assuming that auricular flutter and fibrillation are initiated by rapid impulse formation in a single center. As the impulses thus formed move into the larger mass of auricular muscle, islands of refractory tissue appear, which cause a weaving and interweaving of the contraction process that is characteristic of fibrillation.The increase of auricular rate during vagus stimulation in the presence of auricular flutter is caused by a direct action of the vagus on the center of stimulus formation. Shortening of the refractory phase increases the rate of stimulus formation.When flutter originates in the auricular appendices the increase in rate during vagus stimulation is greater than when it originates in the area of the sinus node. The vagus effect on the refractory phase seems to be less pronounced on specific tissue than on auricular muscle.     

Extrasystoles in groups

Instances of alternation of cycle length during an A-V nodal tachycardia and during a paroxysmal ventricular tachycardia in man are descrbed. In the latter case a similar phenomenon was observed during the change from the tachycardia to sinus rhythm following an intravenous injection of quinine.Application of barium chloride or strophanthin to small areas of the cardiac surface of the dog also causes groups of extrasystoles separated by longer pauses. These arrhythmias were often elicited during vagus and following sympathetic stimulation in these experiments. Finally, the phenomenon was observed during warming of the site of origin of extrasystoles produced by subepicardial injection of strophanthin.Similar observations in the literature are discussed. The different mechanisms which may lead to this disturbance of rhythm are reviewed. Irregular stimulus formation in a center is probable; regular stimulus formation with a disturbance of conduction from the center to the rest of the heart is possible only in some of these tracings.     

Factors related to the development of sensitization to green coffee and castor bean allergens among coffee workers

Background Occupational allergic respiratory symptoms in coffee workers have been frequently reported, but the ultimate cause of sensilization is still debated, castor bean being considered besides green coffee beans. Atopy and cigarette smoking have been suggested as promoting factors of sensitizalion for several occupational allergens. Objective This study was carried out to assess the prevalence of allergic respiratory symptoms and of sensitization to both green coffee beans and castor bean in the whole workforce of a coffee manufacturing plant. Furthermore we wanted to ascertain both the presence of castor bean antigens in the settled dust of the green coffee beans warehouse and the possible crossreactivity between the two beans. Meanwhile, the effect of smoking and atopy was considered. Method: Two-hundred and eleven workers were examined. A questionnaire on oculorhinitis and asthma was administered and skin-prick tests for green coffee beans, castor bean and 15 common inhalant allergens were carried out. Isoelectric focusing, isoelectric focusing immunoblot and radioallergosorbent assay (RAST) inhibition were performed on samples of settled environmental dust from the green coffee area, as well as on castor bean and green coffee beans. Results Ten per cent of the workers complained of oculorhinitis alone and 16% of asthma (nearly always associated with oculorhinitis). The overall prevalence of skin-sensitization was: 15% for green coffee beans, 22% for castor bean, 22% for common allergens. Evidence of sensitization to occupational allergens was more common in smokers, with a more than twofold increase in relative risk. The strong association between skin positivity to common and occupational allergens suggests that atopy acts as an enhancing host factor towards occupational sensitization. The analysis of the dust confirmed the presence of castor bean antigens. Conclusion Our findings indicate that castor bean is the major cause of occupational sensitization among coffee workers, whereas smoking and atopy act as enhancing factors.     

Superior Turbinectomy: Role for a Two-surgeon Technique in Endoscopic Endonasal Transsphenoidal Surgery—Technical Note

We describe a practical technique of superior turbinectomy followed by posterior ethmoidectomy as a less invasive procedure for two-surgeon technique on endoscopic endonasal transsphenoidal surgery. After identification of the superior turbinate and the sphenoid ostium, the inferior third portion of the superior turbinate was coagulated and resected. This partial superior turbinectomy procedure exposed the posterior ethmoidal sinus. Resection of the bony walls between the sphenoid and posterior ethmoid sinuses provided more lateral and superior exposure of the sphenoid sinus. This technique was performed in 56 patients with midline skull base lesions, including 49 pituitary adenomas and 7 other lesions. Meticulous manipulation of instruments was performed in all cases without surgical complications such as permanent hyposmia/anosmia or nasal bleeding. Our findings suggested that the partial superior turbinectomy followed by retrograde posterior ethmoidectomy is a simple and safe technique providing a sufficient surgical corridor for two-surgeon technique to approaching midline skull base regions, mainly involving pituitary adenomas.     

Circulating Megakaryocytes and Platelet Release in the Lung

1. Megakaryocytes were demonstrated in central venous blood of each of23 patients who underwent cardiac catheterization. Cell counts ranged from0.7 to 5.9 megakaryocytes per ml. of blood; the equivalent of one-third ofthese cells were considered to contain a full complement of cytoplasm. It hasbecome evident that megakaryocytes are normal constituents of blood.

2. In an attempt to quantify megakaryocyte migration from the bone marrow it was calculated that from 20-50 per cent of the mature megakaryocytepopulation enters the blood and ultimately reaches the lungs. The possibilitythat all megakaryocytes migrate from the marrow is not precluded with certainty by these studies.

3. It was estimated that from 7-17 per cent of the body’s platelets are released in the pulmonary capillaries. If all megakaryocytes migrate from thebone marrow, then as much as 33 per cent of the platelet population is delivered to the blood in the lungs.

Submitted on January 15, 1965 Accepted on March 13, 1965     

Origin of Pulmonary Megakaryocytes

1. Evidence is presented which indicates that pulmonary megakaryocytesdo not originate in the lungs but elsewhere in the body and are carried tothe lungs in the venous blood.

2. Some megakaryocytes in the lungs evidently deliver platelets to theblood.

3. Surgery is a potent stimulus to megakaryocyte production; the numbersof megakaryocytes found in the lung postoperatively is significantly increased.

Submitted on July 3, 1964 Accepted on September 19, 1964     

Hormonal and metabolic characteristics of geneticall obese Zucker and dietar obese Sprague-Dawle rats

Abstract. The endocrine-metabolic plasma pattern and the capacit of isolated perfused livers to produce triglcerides and ketone bodies have been studied in geneticall and diet-acquired obese rats (Zucker and Sprague-Dawle obese rats), and in control groups of the same strains.
An increased plasma insulin/glucagon molar ratio with hperinsulinaemia and hpoglucagonaemia was associated with hpertriglceridaemia, normal ketonaemia, elevated free fatt acids and normal or slight hperglcaemia in obese rats.
During oleate perfusion, the livers of Zucker and Sprague-Dawle obese rats showed an increase in triglceride output and liver triglceride content. The ketone bod output as well as the mitochondrial carnitine palmitol transferase activit were normal or slightl decreased.
In our rat population, a positive correlation between the insulin/glucagon molar ratio and triglceride output has been found.     

Delayed hypersensitivity to flurbiprofen

Immune-mediated reactions to nonsteroidal antiinflammatory drugs (NSAIDs) are unusual, and true allergy to the drug flurbiprofen has never been documented. We observed a patient who developed a maculopapular rash 48 h after beginning oral therapy with this drug, and 2 days later, angioedema and hypotension. Patch tests with flurbiprofen were positive 48 and 72 h after application. The clinical and allergologic features of this case strongly suggest type IV hypersensitivity. Patch testing with NSAIDs is useful for confirming clinical diagnoses of delayed hypersensitivity to these drugs.     

The association between rifamycin-SV (R-SV) related hyperbilirubinaemia and antipyrine clearance as a new test of liver function in cirrhosis

Abstract. Several clearance tests have been used to assess the residual hepatic efficiency in liver cirrhosis. However, the altered clearance values found in cirrhotic patients may reflect not only the impairment in liver function but also a derangement in the hepatic blood-flow. Therefore, this study was designed to explore the possibility that the competition between Rifamicyn-SV and bilirubin at the hepatic uptake site might be used as an index for quantitative assessment of residual hepatic efficiency in 48 patients with chronic liver disease. In this test, the interference of hepatic blood flow would be negligible. Antipiryne clearance was also evaluated in the same subjects in order to explore the cytoplasmic microsomial efficiency. Rifamicyn-SV intravenous load was followed by a sustained increase in bilirubinaemia which significantly related with the degree of liver function as assessed by the Chil-Pugh criteria. Also, antipiryne clearance was significantly altered in cirrhotic patients compared to controls. Moreover, a positive correlation was found between the Rifamicyn-SV test and Antipiryne clearance. We suggest that a combination of these tests might be of use in the quantitative assessment of liver function.