Enterobacter sp. AA26 gut symbiont as a protein source for Mediterranean fruit fly mass-rearing and sterile insect technique applications

Background

The interaction between gut bacterial symbionts and Tephritidae became the focus of several studies that showed that bacteria contributed to the nutritional status and the reproductive potential of its fruit fly hosts. Anastrepha fraterculus is an economically important fruit pest in South America. This pest is currently controlled by insecticides, which prompt the development of environmentally friendly methods such as the sterile insect technique (SIT). For SIT to be effective, a deep understanding of the biology and sexual behavior of the target species is needed. Although many studies have contributed in this direction, little is known about the composition and role of A. fraterculus symbiotic bacteria. In this study we tested the hypothesis that gut bacteria contribute to nutritional status and reproductive success of A. fraterculus males.

Results

AB affected the bacterial community of the digestive tract of A. fraterculus, in particular bacteria belonging to the Enterobacteriaceae family, which was the dominant bacterial group in the control flies (i.e., non-treated with AB). AB negatively affected parameters directly related to the mating success of laboratory males and their nutritional status. AB also affected males’ survival under starvation conditions. The effect of AB on the behaviour and nutritional status of the males depended on two additional factors: the origin of the males and the presence of a proteinaceous source in the diet.

Conclusions

Our results suggest that A. fraterculus males gut contain symbiotic organisms that are able to exert a positive contribution on A. fraterculus males’ fitness, although the physiological mechanisms still need further studies.

     

Rare causes of scoliosis and spine deformity: experience and particular features

Background

Spine deformity can be idiopathic (more than 80% of cases), neuromuscular, congenital or neurofibromatosis-related. However, there are many disorders that may also be involved. We present our experience treating patients with scoliosis or other spine deformities related to rare clinical entities.

Methods

A retrospective study of the records of a school-screening study in North-West Greece was performed, covering a 10-year period (1992–2002). The records were searched for patients with deformities related to rare disorders. These patients were reviewed as regards to characteristics of underlying disorder and spine deformity, treatment and results, complications, intraoperative and anaesthesiologic difficulties particular to each case.

Results

In 13 cases, the spine deformity presented in relation to rare disorders. The underlying disorder was rare neurological disease in 2 cases (Rett syndrome, progressive hemidystonia), muscular disorders (facioscapulohumeral muscular dystrophy, arthrogryposis) in 2 patients, osteogenesis imperfecta in 2 cases, Marfan syndrome, osteopetrosis tarda, spondyloepiphyseal dysplasia congenita, cleidocranial dysplasia and Noonan syndrome in 1 case each. In 2 cases scoliosis was related to other congenital anomalies (phocomelia, blindness). Nine of these patients were surgically treated. Surgery was avoided in 3 patients.

Conclusion

This study illustrates the fact that different disorders are related with curves with different characteristics, different accompanying problems and possible complications. Investigation and understanding of the underlying pathology is an essential part of the clinical evaluation and preoperative work-up, as clinical experience at any specific center is limited.     

Activity of grape extracts from Greek varieties of Vitis vinifera against mutagenicity induced by bleomycin and hydrogen peroxide in Salmonella typhimurium strain TA102

Several in vivo and in vitro studies have shown that grape extracts could prevent certain steps in carcinogenesis and a few mechanisms have been proposed for this activity. In this study, the potential antimutagenic activity of methanolic and aqueous extracts from two Greek grape varieties of Vitis vinifera against DNA damage induced by reactive oxygen species (ROS) was assessed as a potential novel chemopreventive mechanism, using Salmonella typhimurium strain TA102. The two grape varieties were Assyrtiko (white grapes) and Mandilaria (red grapes), while the oxidant mutagens used were bleomycin (BLM) and hydrogen peroxide (H(2)O(2)). Since it has been considered that polyphenols present in grapes are their most potent biologically active compounds, we also tested the effects of polyphenol-rich fractions as well as some of the more common grape polyphenols on the activity of the two test mutagens. These polyphenols were quercetin, (+)-catechin, (-)-epicatechin, trans-resveratrol, gallic acid and protocatechuic acid. Almost all extracts showed inhibitory activity against both mutagens. On the other hand, polyphenol-rich fractions as well as individual polyphenols at concentrations found in the extracts either did not diminish or did enhance the activity of the mutagens. These results suggest that the protection of DNA from mutations induced by ROS may be one of the mechanisms accounting for the chemopreventive activity of grape extracts. However, it seems that this protective activity may not be attributed to polyphenols but rather to a synergism of many compounds in the grapes.     

Review: Impact of Helicobacter pylori on Alzheimer's disease: What do we know so far?

Background

Helicobacter pylori has changed radically gastroenterologic world, offering a new concept in patients' management. Over time, more medical data gave rise to diverse distant, extragastric manifestations and interactions of the “new” discovered bacterium. Special interest appeared within the field of neurodegenerative diseases and particularly Alzheimer's disease, as the latter and Helicobacter pylori infection are associated with a large public health burden and Alzheimer's disease ranks as the leading cause of disability. However, the relationship between Helicobacter pylori infection and Alzheimer's disease remains uncertain.

Methods

We performed a narrative review regarding a possible connection between Helicobacter pylori and Alzheimer's disease. All accessible relevant (pre)clinical studies written in English were included. Both affected pathologies were briefly analyzed, and relevant studies are discussed, trying to focus on the possible pathogenetic role of this bacterium in Alzheimer's disease.

Results

Data stemming from both epidemiologic studies and animal experiments seem to be rather encouraging, tending to confirm the hypothesis that Helicobacter pylori infection might influence the course of Alzheimer's disease pleiotropically. Possible main mechanisms may include the bacterium's access to the brain via the oral‐nasal‐olfactory pathway or by circulating monocytes (infected with Helicobacter pylori due to defective autophagy) through disrupted blood‐brain barrier, thereby possibly triggering neurodegeneration.

Conclusions

Current data suggest that Helicobacter pylori infection might influence the pathophysiology of Alzheimer's disease. However, further large‐scale randomized controlled trials are mandatory to clarify a possible favorable effect of Helicobacter pylori eradication on Alzheimer's disease pathophysiology, before the recommendation of short‐term and cost‐effective therapeutic regimens against Helicobacter pylori‐related Alzheimer's disease.     

Estimating lagoonal biodiversity in Greece: comparison of rapid assessment techniques

An attempt is made to compare the results of different rapid biodiversity assessment techniques at the pan-Mediterranean, sectorial and local levels. A uniform multivariate pattern exists at the pan-Mediterranean and national (sectorial) levels: lagoons can be different when they host only a few species, but as species numbers increase, lagoons become homogenous in composition. Multivariate techniques cannot distinguish anthropogenically-impacted lagoons from those, which are naturally disturbed. In the pan-Mediterranean context it is the higher taxonomic levels, but in the national and local context it is the most abundant macrobenthic groups (polychaetes, molluscs and crustaceans) and meiobenthos which provide patterns closest to that derived from the species level. Taxonomic distinctness indices applied to polychaete and mollusc inventories provide meaningful results at most levels and scales of observation. These indices seem to be robust enough to discriminate anthropogenically impacted from naturally disturbed lagoons.