Biochemical Differences Between Products of the ADH Locus in Olive Fruit Fly (Bactrocera oleae)

Purified alcohol dehydrogenases from olive fruitflies of genotypes SS, II, and SI were biochemicallycompared. The enzymes were found to differ in thespecific activity, in the influence of pH andtemperature on activity, and in the affinity with differentsubstrate-alcohols. The probable relationships of thesefindings with the dramatic changes in allele frequenciesobserved when natural populations are introduced in the laboratory are discussed.     

Double trisomy (48,XXY,+21) in monozygotic twins: case report and review of the literature

The occurrence of double aneuploidy in the same individual is a relatively rare phenomenon. We describe twin newborns with typical clinical features of Down's syndrome, of which one revealed 48,XXY,+21 GTG-band karyotype. The second newborn died 2 days after its birth, and was clinically diagnosed having Down syndrome. Due to the same clinical features of the twins, the common placenta and amniotic sac, we speculate that they were monozygotics and as a result the second newborn should also be a Klinefelter. The purpose of this report is to present a rare case of possible coincidence of double aneuploidy in newborn twins. A review of the literature showed that double trisomy (48,XXY,+21) in a twin newborn infant has never occurred.     

Greek Students Research the Effects of Fire on the Soil System through Project-based Learning

This study is focused on the development, implementation and evaluation of an environmental education programme for secondary education students. The programme was entitled ‘Τhe effects of fire on the soil system’ and it was implemented during the school period of 2008. Twenty-four (24) students (aged from 15 to 20) coming from Lidoriki Secondary School (Central Greece) participated in the programme, which was based on Project Method. The programme consisted of one theoretical part (achievement of cognitive and affective goals) and one experimental part (achievement of cognitive and psychomotor goals). Initial, formative and summative assessments were implemented during the course of the programme, by means of questionnaires, observation of students’ teamwork and examination of their work sheets. The questionnaire analysis highlighted students’ misconceptions regarding the subject, revealed positive changes in students’ attitudes as a result of their participation in the programme, as well as satisfactory results concerning the acquired knowledge and skills. The experimental results were of significant scientific and educational value.     

A Comprehensive Analysis of Choroideremia: From Genetic Characterization to Clinical Practice

Choroideremia (CHM) is a rare X-linked disease leading to progressive retinal degeneration resulting in blindness. The disorder is caused by mutations in the CHM gene encoding REP-1 protein, an essential component of the Rab geranylgeranyltransferase (GGTase) complex. In the present study, we evaluated a multi-technique analysis algorithm to describe the mutational spectrum identified in a large cohort of cases and further correlate CHM variants with phenotypic characteristics and biochemical defects of choroideremia patients. Molecular genetic testing led to the characterization of 36 out of 45 unrelated CHM families (80%), allowing the clinical reclassification of four CHM families. Haplotype reconstruction showed independent origins for the recurrent p.Arg293* and p.Lys178Argfs*5 mutations, suggesting the presence of hotspots in CHM, as well as the identification of two different unrelated events involving exon 9 deletion. No certain genotype-phenotype correlation could be established. Furthermore, all the patients´ fibroblasts analyzed presented significantly increased levels of unprenylated Rabs proteins compared to control cells; however, this was not related to the genotype. This research demonstrates the major potential of the algorithm proposed for diagnosis. Our data enhance the importance of establish a differential diagnosis with other retinal dystrophies, supporting the idea of an underestimated prevalence of choroideremia. Moreover, they suggested that the severity of the disorder cannot be exclusively explained by the genotype.     

Serum Copper and Zinc Levels in Healthy Greek Children and Their Parents

The aim of this study was to investigate whether there is a correlation between copper (Cu) and zinc (Zn) levels in children and their parents, considering their nutritional habits. Cu and Zn concentrations were measured by flame atomic absorption spectrophotometry in the serum of 66 healthy children, aged 3–14 years, and their parents, residing in a region of Greece (Thrace). Cu levels were higher in mothers than those in fathers, but they were lower in both parents than those in children. They also tended to decrease with age in both parents and children, whereas Zn levels significantly increased with age in children. There was a positive correlation between children's and mothers' Zn levels, as well as children's and both parents' Cu levels. Children used to eat meat, fish, vegetables, and legumes as frequently as their parents, but they were consuming more eggs, milk, and fruits than the latest. Regarding parents' diet, higher Zn levels were depended on the consumption of meat and milk, whereas higher Cu levels were depended on the consumption of milk. Consequently, children’s Cu and Zn levels are related to their parents’ levels, which can be influenced by their nutritional habits.     

Asymmetrical intraguild predation between natural enemies of the citrus mealybug

The ability of a predator to discriminate against parasitized prey determines the extent of asymmetrical intraguild predation, which is often crucial for the outcome of biological control. Anagyrus nr. pseudococci (Girault) (Hymenoptera: Encyrtidae), a parasitoid of the citrus mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae), suffers from intraguild predation by coccinellids occurring in the same habitat. The level of intraguild predation on A. nr. pseudococci by Nephus includens (Kirsch) (Coleoptera: Coccinellidae) at different immature stages has been investigated with and without simultaneous offer of extraguild prey. Larvae of A. nr. pseudococci appeared to face increased intraguild predation at early developmental stages, whereas mummification provided adequate protection against the predatory coccinellid. Different predation levels on unparasitized vs. parasitized hosts at various developmental stages in choice assays indicated that N. includens preferences might be determined not solely by palatability of the prey but also by its ability to protect itself.     

The relationship between mitochondrial shape and function and the cytoskeleton

Mitochondria are crucial organelles for life and death of the cell. They are prominent players in energy conversion and integrated signaling pathways including regulation of Ca2+ signals and apoptosis. Their functional versatility is matched by their morphological plasticity and by their high mobility, allowing their transport at specialized cellular sites. This transport occurs by interactions with a variety of cytoskeletal proteins that also have the ability to influence shape and function of the organelle. A growing body of evidence suggests that mitochondria use cytoskeletal proteins as tracks for their movement; in turn, mitochondrial morphology and function is regulated via mostly uncharacterized pathways, by the cytoskeleton.