A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1

PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4⁺ and CD8⁺ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.     

SIMS microscopy in the biomedical field.

We attempted to indicate the requirements for biomedical applications of SIMS microscopy. Sample preparation methodology should preserve both the structural and the chemical integrity of the tissue. Furthermore, it is often necessary to correlate ionic and light microscope images. This implies a common methodological approach to sample preparation for both microscopes. The use of low or high mass resolution depends on the elements studied and their concentrations. To improve the acquisition and processing of images, digital imaging systems have to be designed and require both ionic and optical image superimposition. However, the images do not accurately reflect element concentration; a relative quantitative approach is possible by measuring secondary ion beam intensity. Using an internal reference element (carbon) and standard curves the results are expressed in micrograms/mg of tissue. Despite their limited lateral resolution (0.5 microns) the actual SIMS microscopes are very suitable for the resolution of biomedical problems posed by action modes and drug localization in human pathology. SIMS microscopy should provide a new tool for metabolic radiotherapy by facilitating dose evaluation. The advent of high lateral resolution SIMS imaging (less than 0.1 microns) should open up new fields in biomedical investigation.     

Life With or Without Names

The terms ‘life’, ‘species’ and ‘individuals’ are key concepts in biology. However, theoretical and practical concerns are directly associated with definitions of these terms and their use in researchers’ work. Although the practical implications of employing definition of ‘species’ and ‘individuals’ are often clear, it is surprising how most biologists work in their field of study without adhering to a specific definition of life. In everyday scientific practice, biologists rarely define life. This is somewhat understandable: the majority of biologists accept the standard definition of life without exploring it, but this represents a bad attitude. In this essay, we update the concepts of life, species, and individuals in the light of the new techniques for massive DNA sequencing collectively known as high throughput DNA sequencing (HTS). A re-evaluation of the newest approaches and traditional concepts is required, because in many scientific publications, HTS users apply concepts ambiguously (in particular that of species). However, the absence of clarity is understandable. For most of the last 250 years, from Linnaeus to the most recent researches, identification and classification have been performed applying the same process. On the contrary, through HTS, biologists have become simply identifiers, who construct boundaries around the biological entities and do not examine the taxa at length, resulting in uncertainty in most readers and displeasure in traditional taxonomists. We organised our essay to answer a basic question: can we develop new means to observe living organisms?     

Real-time PCR for quantification of the bacterial endosymbionts (Wolbachia) of filarial nematodes

Filarial nematodes harbour intracellular symbiotic bacteria belonging to the genus Wolbachia. Wolbachia is thought to play an important role in the biology of the nematode. Moreover, Wolbachia appears to be involved in the immunopathogenesis of filariasis and in the onset of the side-effects of antifilarial therapy. Investigations in these research areas require reliable methods to quantify Wolbachia both in nematodes and in vertebrate tissues. To this purpose, we designed a quantitative real-time PCR targeted on the ftsZ gene of the Wolbachia of Brugia pahangi, a model filarial species maintained in gerbils. The method was applied to quantify Wolbachia in Brugia pahangi, from animals with or without tetracycline treatment. Our results show that tetracycline treatment leads to dramatic reduction or clearance of Wolbachia from the nematode. Results obtained from different replicates were reproducible and the method appeared very sensitive compared to other PCR protocols for Wolbachia detection. Real-time PCR is thus an appropriate method for investigations on the biological role of Wolbachia and on the implication of these bacteria in the pathogenesis of filariasis. With slight modifications of the primers and probe, the protocol we have developed could be applied in studies of the human pathogen Brugia malayi and on the model filarial species Litomosoides sigmodontis.     

Toward a resolution of a taxonomic enigma: first genetic analyses of Paradoxornis webbianus and Paradoxornis alphonsianus (Aves: Paradoxornithidae) from China and Italy

Paradoxornis webbianus and Paradoxornis alphonsianus naturally occur in South-East Asia. Due to a recent introduction, a mixed population currently occurs in northern Italy. A preliminary phylogeographic analysis using samples from Italy and China found little genetic differentiation between the two taxa and revealed the existence of two molecular lineages, sympatric in some part of China, that do not correspond to the morphological classification. Possible taxonomic changes and preliminary inferences on the relationships between Chinese and the Italian populations and on the likely provenance of the founders introduced in Italy are also discussed.     

<Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> inhibits <Emphasis Type="Italic">in-vitro Candida</Emphasis> biofilm development

Background  

Elucidation of the communal behavior of microbes in mixed species biofilms may have a major impact on understanding infectious diseases and for the therapeutics. Although, the structure and the properties of monospecies biofilms and their role in disease have been extensively studied during the last decade, the interactions within mixed biofilms consisting of bacteria and fungi such as Candida spp. have not been illustrated in depth. Hence, the aim of this study was to evaluate the interspecies interactions of Pseudomonas aeruginosa and six different species of Candida comprising C. albicans, C. glabrata, C. krusei, C. tropicalis, C. parapsilosis, and C. dubliniensis in dual species biofilm development.     

Molecular determinants of caste differentiation in the highly eusocial honeybee <Emphasis Type="Italic">Apis mellifera</Emphasis>

Background  

In honeybees, differential feeding of female larvae promotes the occurrence of two different phenotypes, a queen and a worker, from identical genotypes, through incremental alterations, which affect general growth, and character state alterations that result in the presence or absence of specific structures. Although previous studies revealed a link between incremental alterations and differential expression of physiometabolic genes, the molecular changes accompanying character state alterations remain unknown.     

A species-specific qPCR assay provides novel insight into range expansion of the Mediterranean monk seal (Monachus monachus) by means of eDNA analysis

Biodiversity and Conservation - The monk seal is the most endangered pinniped worldwide and the only one found in the Mediterranean, where its distribution and abundance have suffered a drastic...     

Mitochondrial haplotype diversity in the tortoise species <Emphasis Type="Italic">Testudo graeca</Emphasis> from North Africa and the Middle East

Background  

To help conservation programs of the endangered spur-thighed tortoise and to gain better insight into its systematics, genetic variation and evolution in the tortoise species Testudo graeca (Testudines: Testudinidae) was investigated by sequence analysis of a 394-nucleotide fragment of the mitochondrial 12S rRNA gene for 158 tortoise specimens belonging to the subspecies Testudo graeca graeca, Testudo graeca ibera, Testudo graeca terrestris, and a newly recognized subspecies Testudo graeca whitei. A 411-nucleotide fragment of the mitochondrial D-loop was additionally sequenced for a subset of 22 T. graeca, chosen because of their 12S gene haplotype and/or geographical origin.