The efficacy of cisapride vs. placebo and diet in patients with chronic constipation

The effects of cisapride (10 mg three times daily) on the stool evacuation characteristics, laxative consumption (symptom diary) and motility pattern (rectoanal manometry) were assessed in patients with chronic idiopathic constipation who fulfilled Rome II criteria. After a 14-day basal period on a diet rich in fiber (phase I), patients were treated with placebo (n = 20) or cisapride (n = 19) (phase II). Anorectal manometry was performed at the end of each phase. The study was controlled, randomized and double blind. Side effects related to the use of cisapride were noted and found to be mild. Cisapride and placebo increased stool frequency from 4 (1-11) to 7 (14-12) (p < 0.001) and from 4 (2-10) to 6 (2-11) (p < 0.05) per week, respectively. Straining was decreased from 69.0% to 39.7% in the cisapride (p < 0.0001) group, and from 79% to 35% (p < 0.0001) in the placebo group. Both cisapride and placebo decreased the feeling of incomplete evacuation from 91.7% to 37.5% (p < 0.0001) and from 82.7% to 39.2% (p < 0.0001), respectively. Cisapride reduced the need of laxatives and showed a tendency to normalize stool consistency but did not influence any other symptom or bowel motility parameter.     

Mutations in LRRC50 Predispose Zebrafish and Humans to Seminomas

Seminoma is a subclass of human testicular germ cell tumors (TGCT), the most frequently observed cancer in young men with a rising incidence. Here we describe the identification of a novel gene predisposing specifically to seminoma formation in a vertebrate model organism. Zebrafish carrying a heterozygous nonsense mutation in Leucine-Rich Repeat Containing protein 50 (lrrc50 also called dnaaf1), associated previously with ciliary function, are found to be highly susceptible to the formation of seminomas. Genotyping of these zebrafish tumors shows loss of heterozygosity (LOH) of the wild-type lrrc50 allele in 44.4% of tumor samples, correlating with tumor progression. In humans we identified heterozygous germline LRRC50 mutations in two different pedigrees with a family history of seminomas, resulting in a nonsense Arg488* change and a missense Thr590Met change, which show reduced expression of the wild-type allele in seminomas. Zebrafish in vivo complementation studies indicate the Thr590Met to be a loss-of-function mutation. Moreover, we show that a pathogenic Gln307Glu change is significantly enriched in individuals with seminoma tumors (13% of our cohort). Together, our study introduces an animal model for seminoma and suggests LRRC50 to be a novel tumor suppressor implicated in human seminoma pathogenesis.     

High bioreactor production and emulsifying activity of an unusual exopolymer by Chromohalobacter canadensis 28

Unusual composition of an exopolymer (EP) from an obligate halophilic bacterium Chromohalobacter canadensis 28 has triggered an interest in development of an effective bioreactor process for its production. Its synthesis was investigated in 2‐L bioreactor at agitation speeds at interval 600‐1000 rpm, at a constant air flow rate of 0.5 vvm; aeration rates of 0.5, 1.0, and 1.5 vvm were tested at constant agitation rate of 900 rpm. EP production was affected by both, agitation and aeration. As a result twofold increase of EP yield was observed and additionally increased up to 3.08 mg/mL in a presence of surfactants. For effective scale‐up of bioreactors mass transfer parameters were estimated and lowest values of K_La obtained for the highest productivity fermentation was established. Emulsification activity of EP exceeded that of trade hydrocolloids xanthan, guar gum, and cellulose. A good synergism between EP and commercial cellulose proved its potential exploration as an enhancer of emulsifying properties of trade emulsions. A pronounced lipophilic effect of EP was established toward olive oil and liquid paraffin. Cultivation of human keratinocyte cells (HaCaT) with crude EP and purified γ‐polyglutamic acid (PGA) showed higher viability than control group.     

Molecular underpinnings of centromere identity and maintenance

Centromeres direct faithful chromosome inheritance at cell division but are not defined by a conserved DNA sequence. Instead, a specialized form of chromatin containing the histone H3 variant, CENP-A, epigenetically specifies centromere location. We discuss current models where CENP-A serves as the marker for the centromere during the entire cell cycle in addition to generating the foundational chromatin for the kinetochore in mitosis. Recent elegant experiments have indicated that engineered arrays of CENP-A-containing nucleosomes are sufficient to serve as the site of kinetochore formation and for seeding centromeric chromatin that self-propagates through cell generations. Finally, recent structural and dynamic studies of CENP-A-containing histone complexes - before and after assembly into nucleosomes - provide models to explain underlying molecular mechanisms at the centromere.     

Evidence for taxonomic and functional drift of an atrazine-degrading culture in response to high atrazine input

We evaluated the effects of variations in atrazine input on the evolution of a bacterial culture adapted to a low atrazine concentration. This initial culture (M3-K) was subjected to weekly subculturing in the presence of a high concentration of atrazine as the only N source (100 mg l⁻¹). After four subculturing, M3-K evolved to a new bacterial culture (M3) which exhibited a significant increase in the extent of atrazine mineralization in comparison with the initial culture. Molecular analyses of M3-K and M3 cultures by cloning, restriction analysis, and sequencing of the 16S rRNA genes revealed significant differences in culture structure and composition. M3-K culture comprised mainly Actinobacteria (40%), β-Proteobacteria (26%), and Bacteroidetes (16%). After exposure to a high atrazine concentration, the dominance of Actinobacteria decreased (14%), Bacteroidetes increased (27%), and β-Proteobacteria were replaced by γ-Proteobacteria (32%). Quantitative PCR revealed that the abundance of atzB and atzC genes relative to total bacteria decreased by a factor of 3–4 following the increase in atrazine concentration, while the relative abundance of trzD increased significantly (≈400 times). Presented study shows that variations in atrazine input drive both functional and compositional shifts in the atrazine-degrading bacterial culture.     

Chemical and fatty acid composition of male mouflon (Ovis ammon musimon Pal.) meat

The aim of this research was to determine the effect of age on chemical and fatty acid composition of the male mouflon (Ovis ammon musimon Pal.) meat. The male mouflons included in the study originated from the North Adriatic island Rab, Croatia. Three age groups were included (young, sub-adult, adult). An effect of age on chemical composition was not found. However, higher percentage of total fat, dry matter and ash was determined in the meat of young mouflons. Predominating saturated fatty acids in mouflon meat were myristic, palmitic and stearic acids. Age significantly (p < 0.05) affected only the percentage of palmitic acid being the highest in the meat of young mouflons. Percentage of the predominant monounsaturated fatty acid, oleic acid, did not change significantly with age. A higher (p < 0.05) percentage of the predominant polyunsaturated fatty acid, linoleic acid, was found in the meat of sub-adult mouflons. The meat of the young mouflons had a higher (p < 0.05) percentage of conjugated linoleic acid. The meat of the sub-adult and adult mouflons was found to have a higher (p < 0.05) percentage of total saturated fatty acids. A lower (p < 0.05) ratio of polyunsaturated and saturated fatty acids was found in the meat of young than in the meat of sub-adult mouflons. The ratio of n-6 and n-3 was lower (p < 0.05) in the adult than in the sub-adult mouflons. Higher (p < 0.05) atherogenicity and thrombogenicity indices were found in the young rather than in the adult mouflons. Low fat content (<1 %) and favourable ratios of polyunsaturated, saturated, n-6 and n-3 fatty acids make the mouflon meat a good choice for human diet.     

Long-Time Cooling before Cryopreservation Decreased Translocation of Phosphatidylserine (Ptd-L-Ser) in Human Ovarian Tissue

Objectives

To translocation (externalization) of phosphatidylserine lead at least the five negative effects observed during cells cryopreservation: hypoxia, increasing of intracellular Ca²⁺, osmotic disruption of cellular membranes, generation of reactive oxygen species (ROS) and lipid peroxidation. The aim of this study was to test the intensiveness of the phosphatidylserine translocation immediately after thawing and after 45 d xenografting of human ovarian tissue, which was either frozen just after operative removal from patient or cooled before cryopreservation to 5°C for 24 h and then frozen.

Materials and Methods

Ovarian fragments from twelve patients were divided into small pieces in form of cortex with medulla, and randomly divided into the following four groups. Pieces of Group 1 (n=30) were frozen immediately after operation, thawed and just after thawing their quality was analyzed. Group 2 pieces (n=30) after operation were cooled to 5°C for 24 h, then frozen after 24 h pre-cooling to 5°C, thawed and just after thawing their quality was analyzed. Group 3 pieces (n=30) were frozen immediately after operation without pre-cooling, thawed, transplanted to SCID mice and then, after 45 d of culture their quality was analyzed. Group 4 pieces (n=30) were frozen after 24 h pre-cooling to 5°C, thawed, transplanted to SCID mice and then, after 45 d their quality was analyzed. The effectiveness of the pre-freezing cooling of tissuewas evaluated by the development of follicles (histology) and by intensiveness of translocation of phosphatidylserine (FACS with FITC-Annexin V and Propidium Iodide).

Results

For groups 1, 2, 3 and 4 the mean densities of follicles per 1 mm³ was 19.0, 20.2, 12.9, and 12.2, respectively (P_{1-2, 3-4} >0.1). For these groups, 99%, 98%, 88% and 90% preantral follicles, respectively were morphologically normal (P_{1-2, 3-4} >0.1). The FACS analysis showed significantly decreased intensiveness of translocation of phosphatidylserine after pre-cooling of frozen tissue (46.3% and 33.6% in Groups 2 and 4, respectively), in contrast with tissue frozen without pre-cooling (77.1% and 60.2 % in Groups 1 and 3, respectively, P_{1, 3-2, 4} <0.05).

Conclusions

Long time (24 h) cooling of ovarian tissue to 5°C before cryopreservation decreased translocation of phosphatidylserine that evidences about increases the viability of the cells in the tissue after thawing.     

Migfilin’s elimination from osteoarthritic chondrocytes further promotes the osteoarthritic phenotype via β-catenin upregulation

Osteoarthritis (OA) is a debilitating disease of the joints characterized by cartilage degradation but to date there is no available pharmacological treatment to inhibit disease progression neither is there any available biomarker to predict its development. In the present study, we examined the expression level and possible involvement of novel cell–ECM adhesion-related molecules such as Iintegrin Linked Kinase (ILK), PINCH, parvin, Mig-2 and Migfilin in OA pathogenesis using primary human articular chondrocytes from healthy individuals and OA patients. Our findings show that only ILK and Migfilin were upregulated in OA compared to the normal chondrocytes. Interestingly, Migfilin silencing in OA chondrocytes rather exacerbated than ameliorated the osteoarthritic phenotype, as it resulted in even higher levels of catabolic and hypertrophic markers while at the same time induced reduction in ECM molecules such as aggrecan. Furthermore, we also provide a link between Migfilin and β-catenin activation in OA chondrocytes, showing Migfilin to be inversely correlated with β-catenin. Thus, the present study emphasizes for the first time to our knowledge the role of Migfilin in OA and highlights the importance of cell–ECM adhesion proteins in OA pathogenesis.     

Whistle variation in Mediterranean common bottlenose dolphin: The role of geographical,anthropogenic, social,and behavioral factors

The studies on the variation of acoustic communication in different species have provided insight that genetics, geographic isolation, and adaptation to ecological and social conditions play important roles in the variability of acoustic signals. The dolphin whistles are communication signals that can vary significantly among and within populations. Although it is known that they are influenced by different environmental and social variables, the factors influencing the variation between populations have received scant attention. In the present study, we investigated the factors associated with the acoustic variability in the whistles of common bottlenose dolphin (Tursiops truncatus), inhabiting two Mediterranean areas (Sardinia and Croatia). We explored which factors, among (a) geographical isolation of populations, (b) different environments in terms of noise and boat presence, and (c) social factors (including group size, behavior, and presence of calves), were associated with whistle characteristics. We first applied a principal component analysis to reduce the number of collinear whistle frequency and temporal characteristics and then generalized linear mixed models on the first two principal components. The study revealed that both geographic distance/isolation and local environment are associated with whistle variations between localities. The prominent differences in the acoustic environments between the two areas, which contributed to the acoustic variability in the first principal component (PC1), were found. The calf's presence and foraging and social behavior were also found to be associated with dolphin whistle variation. The second principal component (PC2) was associated only with locality and group size, showing that longer and more complex tonal sound may facilitate individual recognition and cohesion in social groups. Thus, both social and behavioral context influenced significantly the structure of whistles, and they should be considered when investigating acoustic variability among distant dolphin populations to avoid confounding factors.