Anatomical site of pheromone accumulation and temporal pattern of pheromone emission in the ambrosia beetle Megaplatypus mutatus

Megaplatypus mutatus (Chapuis) is a native South American ambrosia beetle that attacks live hardwood trees (e.g. Populus spp.), causing important economic losses to commercial plantations. Male beetles release the main components of the sex pheromone, namely (+)‐6‐methyl‐5‐hepten‐2‐ol [(+)‐sulcatol, or retusol] and 6‐methyl‐5‐hepten‐2‐one (sulcatone), when colonizing suitable hosts. The hindgut is shown to be the anatomical site of pheromone accumulation within males, the enantiomeric composition of sulcatol in this tissue is 99%‐(+) and sulcatol is first detectable in this tissue on days 1–2 after gallery initiation. Peak accumulation of sulcatol occurs on days 5–12 after gallery initiation. Trace quantities of sulcatone are also observed during the same period. Both pheromone components are present in male emissions from three host species (Populus×canadensis, Populus alba and Casuarina stricta) between days 2 and 12 after gallery initiation, although sulcatone is always present in low concentrations. The temporal patterns of sulcatol and sulcatone accumulation or storage in male M. mutatus correspond to the temporal patterns of emission.     

Evidence of Actin in the Cytoskeleton of Microsporidia

Using transmission electron microscopy, immuno-electron microscopy, and biochemical techniques such as 2-D electrophoresis and immunoblotting, actin was found in all biological stages of the microsporidia Encephalitozoon hellem and Encephalitozoon cuniculi.     

Microsporidian Spore Wall: Ultrastructural Findings on Encephalitozoon hellem Exospore

A study of the spore wall of Encephalitozoon hellem was performed on thin sections, freeze-fracture, and deep-etched samples to obtain information on spore wall organization and composition. Our observations demonstrate that the spore wall is formed by an inner 30–35 nm electron-lucent endospore and an outer 25–30 nm electron-dense exospore. The exospore is a complex of three layers: an outer spiny layer, an electron-lucent intermediate lamina and an inner fibrous layer. Freeze-fracture and deep-etching techniques reveal that the intermediate lamina and the inner fibrous layer result from the different spatial disposition of the same 4-nm thick fibrils. In thin sections the endospore reveals a scattered electron-dense material that appears in the form of trabecular structures when analyzed in deep-etched samples. The presence of chitin in the exospore is discussed.     

Genetic Diversity in the Microsporidian Encephalitozoon hellem Demonstrated by Pulsed-Field Gel Electrophoresis

Encephalitozoon hellem is a microsporidian species responsible for opportunistic infections in AIDS patients. Use of a novel chitinase-based method allowed unsheared chromosomal DNA to be recovered from eleven E. hellem isolates derived from three geographic regions. All isolates were typed by 18S rDNA sequencing, which showed that they belonged to intemal transcribed spacer type 1. After ethidium bromide staining, pulsed-field gel electrophoresis (PFGE) analysis discriminated two new karyotypes comprising 7 and 8 chromosomal bands respectively, ranging in size from 205- to 272-kb pairs. Genomic size was estimated to be 2.39 Mb. Our data indicate PFGE is useful for typing E. hellem and confirms genetic diversity among E. hellem genotypes.     

CURRENT FUNCTIONS OF ITALIAN ETHICS COMMITTEES: A CROSS‐SECTIONAL STUDY

Background: The rapid pace of progress in medical research, the consequent need for the timely transfer of new knowledge into practice, and the increasing need for ethics support, is making the work of Ethics Committees (ECs) ever more complex and demanding. As a response, ECs in many countries exhibit large variation in number, mandate, organization and member competences. This cross‐sectional study aims to give an overview of the different types of activities of Italian ECs and favour discussion at a European level. Methods: A questionnaire was emailed to all Italian Ethics Committees contained in the national Registry of the Ministry of Health, enquiring whether the EC was conducting, or planning to conduct, 4 specific activities. A telephone interview was conducted to determine reasons for failure to respond. Results: Response rate was 53% (101 respondents out of 191). 20% of ECs restrict their responsibilities to research protocol review, 25% also offer ethical consultation to institutions, support on individual health care decisions and promotes educational initiatives, while the remaining 50% conduct a few of the examined activities to varying degrees. Large variation was observed across different types of hosting institutions and geographical locations. Conclusions: A common European model should be developed, defining EC functions, member selection modalities, necessary member competences, decision‐making criteria and measures for work verification. In the absence of sound empirical evidence, it would be interesting to study the effectiveness and efficiency of the different existing models.