HLA class I in three West African ethnic groups: genetic distances from sub-Saharan and Caucasoid populations

Fulani of Burkina Faso (West Africa) are a particularly interesting ethnic group because of their lower susceptibility to Plasmodium falciparum malaria as compared to sympatric populations, Mossi and Rimaibé. Moreover, the occurrence of a Caucasoid component in their genetic make-up has been suggested on the basis of their physical traits and cultural traditions even though this view was not supported by genetic studies. A total of 149 unrelated subjects (53 Mossi, 47 Rimaibé and 49 Fulani) have been typed for 97 HLA class I alleles with the amplification refractory mutation system/polymerase chain reaction (ARMS/PCR) technique. Mossi and Rimaibé data were pooled since none of the 42 statistically testable alleles exhibited a significant heterogeneity. These pooled gene frequencies were found to be very different from those of Fulani: a certain (P<0.001) or a likely (0.001 I in the higher resistance to malaria of Fulani, and confirms a low, if any, Caucasoid component in their gene pool.     

Alteration of regulatory enzyme activities in fast-twitch and slow-twitch muscles and muscle fibres in low-intensity endurance-trained rats

The effect of progressive, low-intensity endurance training on regulatory enzyme activities in slow-twitch (ST) and fast-twitch (FT) muscle fibres was studied in 32 rats. Of those rats 16 were trained on a treadmill at a running speed of 10m · min^–1 5 days a week over an 8-week period. Running time was progressively increased from 15 min to 2 h · day^–1. Of the rats 4 trained and 4 sedentary rats were also subjected to acute exhausting exercise. Enzyme activities of phosphofructokinase 1 (PFKI) from glycolysis, INE" BORDER="0">-ketoglutarate dehydrogenase (INE" BORDER="0">-KGDH) from the Krebs cycle and carnitine palmitoyltransferase (CPT I and II) from fatty acid metabolism in soleus, tibialis anterior and gastrocnemius muscles were measured in trained and sedentary rats. Enzyme activities of individual ST and FT fibres were measured from the freeze-dried gastrocnemius muscle of 8 trained and 8 sedentary rats. In the sedentary rats the activity of PFK1 in tibialis anterior and soleus muscles was 141% and 41% of the activity in gastrocnemius muscle, respectively. The activity of INE" BORDER="0">-KGDH in tibialis anterior and soleus muscles was 164% and 278% of the activity in gastrocnemius muscle, respectively. The activity of CPT I in tibialis anterior and gastrocnemius muscles were at the same level, but in soleus muscle the activity was 127% of that in mixed muscle. Endurance training increased enzyme activities of INE" BORDER="0">-KGDH and CPT I significantly (P < 0.05) in gastrocnemius muscle but not in soleus or tibialis anterior muscle. After training both INE" BORDER="0">-KGDH and CPT II activities were elevated significantly (P < 0.05) in the ST fibres of gastrocnemius muscle, whereas in FT fibres only INE" BORDER="0">-KGDH was increased. For PFK1 activity no significant change was observed in ST or FT fibres. After acute exercise, activities of mitochondrial enzymes INE" BORDER="0">-KGDH and CPT I tended to be elevated in all muscles. Thus, low-intensity endurance training induced significant peripheral changes in regulatory enzyme activities in oxidative and fatty acid metabolism in individual ST or FT muscle fibres.     

Bestimmung der Plasma-Renin-Konzentration mittels Radioimmunoassays für Angiotensin I

Zusammenfassung Ein Radioimmunoassay für Angiotensin I und seine Anwendung für die Messung der Reninkonzentration im Plasma werden beschrieben. Die zur Herstellung von Angiotensinantikörpern und radioaktiv markiertem Angiotensin sowie zur Trennung von gebundenem und freiem Hormon benutzten Verfahren werden mitgeteilt. Die Empfindlichkeit der Methode erlaubt den Nachweis von zwanzig Pikogramm Angiotensin I.Zur Messung der Reninkonzentration wurde substratfreies Plasma mit Schafsubstrat im Überschuß versetzt und in Anwesenheit von Inhibitoren von IDDLE" BORDER="0">converting enzymeIDDLE" BORDER="0"> und Angiotensinasen bei 37°C inkubiert. Das gebildete Angiotensin wurde in 20 µl des proteinfreien Inkubationsgemisches bestimmt. Die initiale Geschwindigkeit der Angiotensinbildung wurde zur Berechnung der Reninkonzentration herangezogen. Als eine Einheit wurde die Reninmenge definiert, die ein Nanogramm Angiotensin I pro Stunde Inkubation bildet.Normalwerte unter kontrollierter natriumreicher und natriumarmer Diät wurden ermittelt.Die Empfindlichkeit der Methode erlaubt die Messung der Reninkonzentration im Plasma von Patienten mit primärem Aldosteronismus.Mit Unterstützung der Deutschen Forschungsgemeinschaft.     

Allergologic exploration of germins and germin-like proteins,a new class of plant allergens

BACKGROUND: Germins and the related germin-like proteins (GLPs) are glycoproteins expressed in many plants in response to biotic and abiotic stress. To test the potential impact of germins and GLPs, recombinant germin from Triticum aestivum (tGermin) and GLPs from Arabidopsis thaliana (tGLP), both produced in transformed tobacco plants, were used. METHODS: Sera from 82 patients with type I allergy to birch, grass or mugwort pollen and/or wheat were tested in immunoblot for IgE binding to tGermin and tGLP, and the IgE reactivity after chemical and enzymatic deglycosylation was analysed. The biological activity of tGermin and tGLP was determined in a histamine release assay and in skin prick testing (SPT). RESULTS: In an immunoblotting assay, 24 out of 82 tested sera (29.26%) from allergic patients showed IgE-binding to tGermin, and 18 of these sera (21.95%) displayed also IgE-binding to tGLP. The deglycosylation experiments indicated that glycan moieties contribute significantly to the IgE-binding of tGermin and tGLP. Both tGermins and tGLP induced specifically histamine release in an in vitro assay as well as in SPT. CONCLUSION: Our in vitro and in vivo findings demonstrate that germin and GLPs are capable to bind IgE most likely via carbohydrate determinants, and represent allergenic molecules.     

Immunohistochemical localization of apolipoproteins A-I and B in human carotid arteries

Decreased plasma levels of apolipoprotein A-I (apo A-I) and increased plasma levels of apolipoprotein B (apo B) have been shown to correlate with increased risk of atherosclerosis. While many studies have investigated the plasma levels of these apolipoproteins with regard to their value as predictors of cardiovascular disease, comparatively little is known about their precise tissue localization in atherosclerotic plaques. The purpose of this study was to determine the tissue localization of apo A-I and apo B in atherosclerotic segments of human carotid arteries through the use of immunohistochemical techniques. With tissue samples obtained from surgery and autopsy, apo A-I and apo B were found to be present in atherosclerotic plaques and absent in normal arterial tissue. In the plaques, both apo A-I and apo B were found extracellularly, primarily in the lipid core, but also in connective tissue. In addition, both apo A-I and apo B were found intracellularly in foam cells. This similar intracellular and extracellular distribution of apo A-I and apo B was unexpected, in view of their differing associations with atherosclerosis.     

The effect of beta adrenergic blockade on bronchial sensitivity to acetyl-beta-methacholine in normal and allergic rhinitis subjects.

The effect of propranolol inhalation on sensitivity to methacholine inhalation was studied in normal and allergic rhinitis subjects to determine whether beta adrenergic blockade alters sensitivity to mediators in nonasthmatic atopic individuals. A partial beta adrenergic blockade is suggested as being instrumental in asthma. Hay fever patients studied showed similar effects and also developed asthma for the first time.     

Clinical diagnosis of the Usher syndromes

The Usher syndromes are genetically distinct disorders which share specific phenotypic characteristics. This paper describes a set of clinical criteria recommended for the diagnosis of Usher syndrome type I and Usher syndrome type II. These criteria have been adopted by the Usher Syndrome Consortium and are used in studies reported by members of this Consortium. © 1994 Wiley-Liss, Inc.