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Osteoporosis is a systemic disorder of decreased skeletal mass as measured by bone mineral density (BMD), and disturbed skeletal architecture and function which results in an increased risk for bone fractures with consecutively increased morbidity and mortality. Twin and family studies have shown an important genetic component of BMD of about 40-60%. This exceeds other well known factors influencing BMD such as environmental factors like dietary calcium, physical activity or several drugs and diseases. Therefore, interest increased in the genetic background of bone mineral density. Polymorphisms of the Vitamin D receptor gene were the first to be published in this area. Studies on other loci or candidate genes such as the estrogen receptor gene or the collagen type I alpha1 gene also showed associations with bone mineral density that could explain at least a part of the genetic background of osteoporosis. Recently published data suggest that these genetic markers of bone metabolism are important in interaction with each other or in certain bone-affecting diseases. In the future, genetic studies on osteoporosis will have to screen further relevant genes and markers for bone metabolism as well as to evaluate the complex interactions of genetic influences, so that it would be possible to calculate a patient's individual risk for osteoporosis in the context of environmental influences.

Three different homogeneous cellulases were isolated by ultrogel chromatography and preparative electrophoresis from the gut of larvae of Ergates faber (Coleoptera:Cerambycidae). Molecular weights (25,000 for A, 57,000 for B and 70,000 for C), optimum pH values and thermolabilities are different. Enzyme A is a 1,4-β- d -glucan cellobiohydrolase (EC 3.2.1.91) inactive on cellobiose and o- nitrophenyl β-glucoside. The two others are enzymes of wide specificity, splitting the β-glucosidic linkages of the five substrates tested. During the early phases of reaction the three cellulases can act synergically. The cellulolytic activity of this insect results from a combination of enzymes, as is the case for bacteria and fungi.

Six strains of yeasts were isolated from P. semipunctata larval gut in order to determine their role in insects nutrition. P. semipunctata larvae possess a rich glycosidasic equipment acting on oligosaccharides, heterosides and polysaccharides which is particularly characterized by an activity on hemicellulose. The yeast strains hydrolyze oligosaccharides, heterosides and some polysaccharides, such as starch and pectin, but no activity was detected on cellulose. β-Glucosidase was secreted in the medium by all strains except one. B group vitamins were also secreted by the yeasts.

Les larves et les adultes de la bruche du haricot se nourrissent de deux types d'aliments differents, mais proches en ce qui concerne la composition en hydrates de carbone: les larves consomment des graines de Phaseolus vulgaris et P. coccineus, les adultes s'alimentent principalement avec le pollen de diverses plantes. L'activite des larves et des adultes a ete etudiee sur 22 substrats differents, en vue de preciser les caracteristiques de leur equipement osidasique. Les recherches ont montre que les larves et les adultes possedent un equipement tres important en α- et β-glucosidases, en α- et β-galactosidases, ainsi que des activites tres importantes sur certains polysaccharides, notamment l'amidon et la pectine, mais l'activite est faible sur les hemicelluloses etudiees, notamment la xylane, l'arabinogalactane et la glucomannane. Les activites sur la carboxymethylcellulose et la cellulose, ainsi que l'inuline, sont nulles. La correlation etroite entre la composition en hydrates de carbone de la nourriture et les activites glycosidasiques du canal alimentaire chez les larves et les adultes permet une utilisation optimale des ressources trophiques en hydrates de carbone. Le parallelisme frappant entre le systeme glycosidasique des larves et celui des adultes a pour explication la ressemblance entre la composition en carbohydrates du pollen et celle de l'endosperme de haricot. Summary Study of glycosidase activities of the digestive tract of the larvae and adults in Acanthoscelides obtectus (Coleoptera: Bruchidae) Adults and larvae of Acanthoscelides obtectus eat two different types of food, similar in carbohydrate composition: larvae eat seeds of Fhaseolus vulgaris and P. coccineus, adults eat principally pollen of various plants. The authors have studied the digestive activity of larvae and adults on 22 different sugars, in order to investigate activity of their glycosidase enzymes. Larvae and adults have a very important complement of α- and β-glucosidases, α- and β-galactosidases, and very high activity against certain polysaccharides, notably starch and pectin. The activity is weak on the hemicelluloses tested, notably on xylan, arabinogalactan and glucomannan. No activity is found on carboxymethylcellulose, cellulose and inuline. The close correlation between the carbohydrate composition of the food and the glycosidase activity of the alimentary canal in both larvae and adults enables optimal utilization of carbohydrate resources. The striking parallel between the glycosidase systems of adults and larvae is explained by the similar carbohydrate composition of pollen and bean endosperm.

1. 1. Two amylases were purified from Phoracantha semipunctata larvae (Coleoptera, Cerambycidae) in one step by affinity chromatography on cross-linked starch. 2. 2. Both enzymes are activated by chloride ions. They differ in their optimum pH, pI and action pattern. 3. 3. Amylase I can be classified as an exoamylase which splits amylose in maltotetraose units from the end of the polysaccharide chain. Amylase II behaves as a typical endoamylase (α-amylase).

Yeasts from the digestive tract of Ips sexdentatus were isolated. Four strains, representing the different identified yeast species, were chosen. Their enzymatic activity on oligosaccharides, heterosides and polysaccharides was measured. Moreover, we showed that they excrete some B group vitamins which are necessary for the insect, unable to synthesize them.

Bruchus affinis Frol. (Coleoptera: Bruchidae), espece monovoltine, passe une grande partie de sa vie imaginale en etat d'hivernation dans des abris naturels. Les adultes hivernants, sexuellement immatures, peuvent redevenir momentanement actifs a l'occasion de rechauffements temporaires au cours de l'hiver; il est probable qu'ils se nourrissent alors de microorganismes. Les caracteristiques generales de l'equipement osidasique digestif de B. affinis ont ete determinees a partir d'adultes maintenus en conditions artificielles. L'α-glucosidase s'est revelee etre l'osidase la plus active de l'equipement enzymatique qui, par ordre d'activite decroissante, comporte egalement une α-mannosidase, une β-galactosidase, une β-mannosidase, une α-galactosidase et une β-glucosidase La comparaison des activites osidasiques des adultes en hivernation a l'exterieur avec celles d'invertebres de la litiere montre que B. affinis pourrait, durant l'hivernation, consommer divers microorganismes (levures, champignons, bacteries, …). B. affinis possederait en fait un equipement osidasique digestif assez etroitement specialise qui, au cours du cycle biologique de l'insecte, pourrait evoluer en fonction des variations saisonnieres du milieu trophique.

In der vorliegenden Arbeit werden die Biologie der in Haute-Savoie gefundenDryocoetes hectographusReit. und die Nematoden, die in der Leibeshohle und im Verdauungs-Apparat dieses Insektes (Scolytidae) leben, behandelt.

Our intention here is to show the different ways in which chemometrics can aid in the comprehension of the biological phenomenon of primary attraction. First of all, what is chemometrics? Chemometrics represents a group of mathematical, statistical, and computing methods which are used to optimize the collection of chemical information and to structure that data to answer whatever question has been posed.

Nine Scolytidae (Cryphalus piceae, Cryphalus abietis, Pityokteines curvidens, Dendroctonus micans, Ips sexdentatus, Ips typographus,Orthotomicus erosus, Tomicus piniperda, andPhloeosinus bicolor) were subjected to olfaction tests on ten conifer species taken two by two. These conifers wereAbies cephalonica, Abies nordmanniana, Picea abies, Picea orientalis, Pinus pinaster, Pinus sylvestris, Pinus brutia, Pinus laricio,Cupressus atlantica, andCupressus sempervirens. A statistical study of the results, by means of the factorial analysis of correspondence completed by the duo preference test, commonly used in sensory analysis, revealed a taxonomic clustering by genus of the plant species and analogous specific attraction behavior for the insects.Pityokteines curvidens has a behavior analogous to that of the twoCryphalus considered.Phloesinus bicolor shows a very strong specificity forCupressus. The essential oils of the conifers were analyzed to determine their terpene composition and the ten odor spectra thus obtained were compared. The hierarchical classification, using a Euclidian distance, brought out similarities in the spectra, especially in the case ofPinus. It is shown that definitive establishment of Scolytidae is not due to the presence in the odor spectrum of any particular terpenoid. The attractive power of a species results from the synergism of the different terpenes. Moreover the definitive establishment of the insects also depends on their sensorial adaptation to volatile substances which can be wider or narrower for the species studied.

The authors present here the results of their research concerning the study of the osidases of the caterpillars Cossus cossus L. and Zeuzera pyrina L. (Lepidoptera Cossidae). Its enzyme equipment shows very important differences compared to the different species of Scolytidae, Cerambycidae, Curculionidae and Buprestidae. The differences are lie especially in the absence of some osidases acting on polysaccharides (hémicelluloses and cellulose).

This paper will emphasize studies of sex attractant in the polygamus species of Scolytidae genus (Phloeosinus, Pityogenes, Pityophthorus) and monogamus species genus Cryphalus, Blastophagus. The secondary attractant or "sex pheromone" was localized in the frass material produced by male beetle in polygamus bark beetles and by female in monogamus species; pheromone specificity has been studied in differents species Phloeosinus, Pityogenes, Pityophthorus, etc. This specificity was evaluated by exposing groups of female beetles to comparable quantities of frass from male polygamus bark beetles.

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