Vererbungswissenschaft und Rassenhygiene

Ohne Zusammenfassung     

Helicase Hmi1 stimulates the synthesis of concatemeric mitochondrial DNA molecules in yeast Saccharomyces cerevisiae

Hmi1p is a helicase in the yeast Saccharomyces cerevisiae required for maintenance of the wild-type mitochondrial genome. Disruption of the HMI1 ORF generates ^– and ⁰ cells. Here we demonstrate that, in ^– yeast strains, Hmi1p stimulates the synthesis of long concatemeric mitochondrial DNA molecules associated with a reduction in the number of nucleoids used for mitochondrial DNA packaging. Surprisingly, the ATPase negative mutants of Hmi1p can also stimulate the synthesis of long concatemeric ^– mitochondrial DNA molecules and support the maintenance of the wild-type mitochondrial genome, albeit with reduced efficiency. We show that, in the mutant hmi1–5 background, the wild-type mitochondrial DNA is fragmented; and we propose that, in hmi1 yeast cells, the loss of the wild-type mitochondrial genome is caused by this fragmentation of the mitochondrial DNA.     

The Q angle and sport

Quadriceps muscle contraction tends to straighten the Q angle. We expected that sports comprising a high amount of quadriceps training could be associated with low Q angles. The aim of the present study was to estimate the Q angle in athletes and to investigate its potential associations with participation in sport. Three hundred and thirty-nine athletes had their Q angle measured. The mean of right-side Q angles was higher than left side, and the mean Q angle was higher in women than in men. The Q angle was positively associated with years of jogging, and negatively with years of soccer, swimming and sports participation at all. It is concluded that the use of Q angle measurements is questionable.     

Referate

Ohne Zusammenfassung

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Referate

     

CARDIOVASCULAR EFFECTS OF BETA-RECEPTOR BLOCKING DRUGS DURING HALOTHANE ANAESTHESIA IN MAN

Fifteen patients anaesthetized with halothane were given a beta-adrenergic receptor blocking substance intravenously, either propranolol or l-alprenolol.
The drugs usually induced an insignificant drop in blood pressure, a slight bradycardia, and a small reduction in cardiac output in patients not subjected to concomitant surgery. In one patient, the reaction was more pronounced. The immediate administration of atropine seemed to restore the circulatory state.
Nine patients were subjected to surgery during the administration of the beta-blocking agents. Pronounced hypotension resulted in seven of them. This effect was observed both after propranolol and l-alprenolol. Again, atropine reversed the hypotension.
These observations suggest that the administration of beta-adrenergic receptor blocking agents during anaesthesia should be limited by very strict indications, and be used under carefully controlled conditions.

ZUSAMMENFASSUNG

15 mit Halothan narkotisierte Patienten erhielten i.v. einen Beta-Rezep-torenblocker, und zwar entweder Propanolol oder 1-Alprenolol.
Diese Mittel fiihrten in der Regel zu einem nicht-signifikanten Blutdruck-abfall, zu einer geringgradigen Bradykardie und einer leichten Verminderung des Herzminutenvolumens bei Patienten, die nicht gleichzeitig operiert wurden. Bei einem Patienten war die Reaktion dramatischer. Die sofortige Gabe von Atropin schien den Kreislaufzustand wieder zu normalisieren.
Neun Patienten erhielten Betablocker wahrend einer Operation. Bei sieben von ihnen kam es zu ausgepragten Blutdruckabfall. Diese Wirkung wurde sowohl nach Propranolol als auch nach 1-Alprenolol beobachtet.
Diese Beobachtungen geben Grund zur Empfehlung, Betarezeptoren-blocker wahrend der Narkose nur bei strengster Indikation zu verabreichen und sie nur unter sorgfaltig kontrollierten Bedingungen anzuwenden.     

Natural History of Epileptic Seizures

Since 1963 a continuous registration of patients with epileptic seizures has been carried out in Greater Aarhus, Denmark. This registration has been attempted by means of medical records dating back to 1940. On the basis of the established prevalence and the calculated cumulated incidence, we have tried to describe the natural history of the different types of epilepsy. The prevalence of all types of epileptic seizures (including febrile convulsions) has been found to be 2,441/100,000, whereas for patients with the diagnosis of epilepsy the rate is 1,274/100,000. The study describes the natural history of the different types of epilepsy. In addition, the risk-increasing effect of a febrile convulsive seizure on the development of epilepsy is analyzed.