Microgravity-induced alterations in cultured testicular cells

Cultured STe cells (2n karyotype) from swine testis were submitted to simulated microgravity using a 3D Random Positioning Machine for 5 min., 15 min., 30 min., 1 h and 23 h. Sample processing included: histological characterization of cell types, immunohistochemical identification of (i) microtubules (a-tubulin), (ii) alkaline phosphates, (iii) 3 beta-hydroxy-steroid-dehydrogenase (3?-HSDH), and histochemical lipid analyses. After 5 min. simulated microgravity a slight microtubule disorganisation occurred, which increased dramatically with increasing microgravity duration. After 23 h microtubule arrays were completely disrupted. 3 beta-HSDH immunostaining was detectable only in one cell type: under control conditions and 5 min. into microgravity immunoreactivity was strong, but completely disappeared thereafter. Immunostaining intensity for alkaline phosphates, a good marker for myoid cells, decreased after 15 min. in microgravity.     

Analytical SAR computation in a multilayer elliptic cylinder: the near-field line-current radiation case

In this paper, a previously proposed analytical procedure for the computation of the specific absorption rate (SAR) inside a biological elliptic cylinder model is extended to the case in which the body is illuminated under near-field conditions. The elliptic model is made up of layers of different biological tissues and the source is constituted by a line-current distribution. The recursive procedure in which the field is expressed in terms of Mathieu function is modified to express the incident electromagnetic wave produced by the line current. The new procedure makes it possible to check and validate numerical solutions obtained by accurate numerical techniques for SAR prediction, under more realistic illumination condition.     

Kinetic analysis of lipid-hydroperoxides in plasma

We increased the precision of chemiluminescent procedure for measuring lipid hydroperoxides in plasma or lipoproteins by (i) escaping from extraction and chromatography of lipids, (ii) using detergent dispersed lipids, and (iii) calculating the results by fitting the photon emission rate with the integrated equation, which describes the model of the series of reactions. The use of kinetics instead of the crude integration of cps increases precision because at each measurement the correct reaction pathway is tested. This was relevant for the optimization of the analytical procedure, contributing to the elimination of possible side reactions. The relationship between lipid hydroperoxide content in the sample and cps is not linear; thus, the calculation of results through internal calibration is carried out using an exponential equation. This is in agreement with the reaction mechanism and raises the point of the linear calibration previously reported in other chemiluminescent procedures. Although sensitive and precise, this procedure suffers for being time consuming, requiring approximately 30 min per sample. Moreover, since no chromatography is used, information about the hydroperoxides in different lipid classes is missing. Obviously this will be solved when a validated procedure for quantitatively extracting lipid hydroperoxides is available.     

Arrival of Paleo-Indians to the Southern Cone of South America: New Clues from Mitogenomes

With analyses of entire mitogenomes, studies of Native American mitochondrial DNA (mtDNA) variation have entered the final phase of phylogenetic refinement: the dissection of the founding haplogroups into clades that arose in America during and after human arrival and spread. Ages and geographic distributions of these clades could provide novel clues on the colonization processes of the different regions of the double continent. As for the Southern Cone of South America, this approach has recently allowed the identification of two local clades (D1g and D1j) whose age estimates agree with the dating of the earliest archaeological sites in South America, indicating that Paleo-Indians might have reached that region from Beringia in less than 2000 years. In this study, we sequenced 46 mitogenomes belonging to two additional clades, termed B2i2 (former B2l) and C1b13, which were recently identified on the basis of mtDNA control-region data and whose geographical distributions appear to be restricted to Chile and Argentina. We confirm that their mutational motifs most likely arose in the Southern Cone region. However, the age estimate for B2i2 and C1b13 (11–13,000 years) appears to be younger than those of other local clades. The difference could reflect the different evolutionary origins of the distinct South American-specific sub-haplogroups, with some being already present, at different times and locations, at the very front of the expansion wave in South America, and others originating later in situ, when the tribalization process had already begun. A delayed origin of a few thousand years in one of the locally derived populations, possibly in the central part of Chile, would have limited the geographical and ethnic diffusion of B2i2 and explain the present-day occurrence that appears to be mainly confined to the Tehuelche and Araucanian-speaking groups.     

Cholecystokinin in White Sea Bream: Molecular Cloning,Regional Expression,and Immunohistochemical Localization in the Gut after Feeding and Fasting

Background

The peptide hormone cholecystokinin (CCK), secreted by the midgut, plays a key role in digestive physiology of vertebrates including teleosts, by stimulating pancreatic secretion, gut motility, and gallbladder contraction, as well as by delaying gastric emptying. Moreover, CCK is involved in the regulation of food intake and satiation. Secretion of CCK by the hindgut is controversial, and its biological activity remains to be elucidated. The present paper addresses the regional distribution of intestinal CCK in the white sea bream, Diplodus sargus, as well as the possible involvement of hindgut CCK in digestive processes.

Methodology/Principal Findings

Full-lengths mRNAs encoding two CCK isoforms (CCK-1 and CCK-2) were sequenced and phylogenetically analyzed. CCK gene and protein expression levels in the different gut segments were measured 3 h and 72 h after feeding, by quantitative real-time RT-PCR and Western blot, respectively. Moreover, endocrine CCK cells were immunoistochemically detected. Fasting induced a significant decrease in CCK-2 in all intestinal segments, including the hindgut. On the other hand, no significant difference was induced by fasting on hindgut CCK-1.

Conclusions/Significance

The results demonstrated two CCK isoforms in the hindgut of D.sargus, one of which (CCK-2) may be involved in the feedback control of uncompleted digestive processes. On the other hand, a functional role alternative to regulation of digestive processes may be inferred for D.sargus CCK-1, since its expression was unaffected by feeding or fasting.     

Novel PTCH1 Mutations in Patients with Keratocystic Odontogenic Tumors Screened for Nevoid Basal Cell Carcinoma (NBCC) Syndrome

Keratocystic odontogenic tumors (KCOTs) are cystic tumors that arise sporadically or associated with nevoid basal cell carcinoma syndrome (NBCCS). NBCCS is a rare autosomal dominantly inherited disease mainly characterized by multiple basal cell carcinomas, KCOTs of the jaws and a variety of other tumors. PTCH1 mutation can be found both in sporadic or NBCCS associated KCOTs. The aim of the current study was to assess whether a combined clinical and bio-molecular approach could be suitable for the detection of NBCCS among patients with a diagnosis of keratocystic odontogenic tumors (KCOTs). The authors collected keratocystic odontogenic tumors recorded in the database of the Pathology Department of the University of Modena and Reggio Emilia during the period 1991-2011. Through interviews and examinations, family pedigrees were drawn for all patients affected by these odontogenic lesions. We found out that 18 of the 70 patients with KCOTs and/or multiple basal cell carcinomas actually met the clinical criteria for the diagnosis of NBCCS. A wide inter- and intra-familial phenotypic variability was evident in the families. Ameloblastomas (AMLs) were reported in two probands that are also carriers of the PCTH1 germline mutations. Nine germline mutations in the PTCH1 gene, 5 of them novel, were evident in 14 tested probands. The clinical evaluation of the keratocystic odontogenic tumors can be used as screening for the detection of families at risk of NBCCS. Keratocystic odontogenic lesions are uncommon, and their discovery deserves the search for associated cutaneous basal cell carcinomas and other benign and malignant tumors related to NBCCS.     

Molecular Dissection of the Basal Clades in the Human Y Chromosome Phylogenetic Tree

One hundred and forty-six previously detected mutations were more precisely positioned in the human Y chromosome phylogeny by the analysis of 51 representative Y chromosome haplogroups and the use of 59 mutations from literature. Twenty-two new mutations were also described and incorporated in the revised phylogeny. This analysis made it possible to identify new haplogroups and to resolve a deep trifurcation within haplogroup B2. Our data provide a highly resolved branching in the African-specific portion of the Y tree and support the hypothesis of an origin in the north-western quadrant of the African continent for the human MSY diversity.     

Autocrine role of angiopoietins during megakaryocytic differentiation

The tyrosine kinase Tie-2 and its ligands Angiopoietins (Angs) transduce critical signals for angiogenesis in endothelial cells. This receptor and Ang-1 are coexpressed in hematopoietic stem cells and in a subset of megakaryocytes, though a possible role of angiopoietins in megakaryocytic differentiation/proliferation remains to be demonstrated. To investigate a possible effect of Ang-1/Ang-2 on megakaryocytic proliferation/differentiation we have used both normal CD34(+) cells induced to megakaryocytic differentiation and the UT7 cells engineered to express the thrombopoietin receptor (TPOR, also known as c-mpl, UT7/mpl). Our results indicate that Ang-1/Ang-2 may have a role in megakaryopoiesis. Particularly, Ang-2 is predominantly produced and released by immature normal megakaryocytic cells and by undifferentiated UT7/mpl cells and slightly stimulated TPO-induced cell proliferation. Ang-1 production is markedly induced during megakaryocytic differentiation/maturation and potentiated TPO-driven megakaryocytic differentiation. Blocking endogenously released angiopoietins partially inhibited megakaryocytic differentiation, particularly for that concerns the process of polyploidization. According to these data it is suggested that an autocrine angiopoietin/Tie-2 loop controls megakaryocytic proliferation and differentiation.     

Interspecific comparison of the performance of soaring migrants in relation to morphology, meteorological conditions and migration strategies

Background

Performance of migrating birds can be affected by a number of intrinsic and extrinsic factors like morphology, meteorological conditions and migration strategies. We compared travel speeds of four raptor species during their crossing of the Sahara desert. Focusing the analyses on this region allows us to compare different species under equivalent conditions in order to disentangle which factors affect migratory performance.

Methodology/Principal Finding

We tracked raptors using GPS satellite transmitters from Sweden, Spain and Italy, and evaluated their migratory performance at both an hourly and a daily scale. Hourly data (flight speed and altitude for intervals of two hours) were analyzed in relation to time of day, species and season, and daily data (distance between roosting sites) in relation to species, season, day length and tailwind support.

Conclusions/Significance

Despite a clear variation in morphology, interspecific differences were generally very small, and did only arise in spring, with long-distance migrants (>5000 km: osprey and Western marsh-harrier) being faster than species that migrate shorter distances (Egyptian vulture and short-toed eagle). Our results suggest that the most important factor explaining hourly variation in flight speed is time of day, while at a daily scale, tailwind support is the most important factor explaining variation in daily distance, raising new questions about the consequences of possible future changes in worldwide wind patterns.