Occurrence and Identification of Yeast Species in Fermented Liquid Feed for Piglets

The major objective of the present study was to investigate the occurrence and identity of yeast species in fermented liquid feed (FLF) used for feeding piglets. In total, 40 different Danish farms were included in the analysis. The preparation and composition of FLF was found to be very heterogeneous with high variations in both yeast counts and yeast species composition. The yeast population varied between 6.0?×?10³ and 4.2?×?10⁷?cfug^?1 with an average yeast count of 8.7?×?10⁶?±?1.1?×?10⁷?cfug^?1. A total of 766 yeasts were isolated and identified by conventional and/or molecular typing techniques. The predominant yeast species in the FLF samples were found to be Candida milleri (58.4%), Kazachstania exigua (17.5%), Candida pararugosa (6.40%) and Kazachstania bulderi (5.09%). No clear separation between isolates of C. milleri and Candida humilis could be obtained based on sequencing of the D1/D2 region of the 26S rRNA gene. The combined use of ITS-RFLP analysis and phenotypic criteria did meanwhile suggest a closer relationship with C. milleri than C. humilis.     

The Arabidopsis thaliana PPX/PP4 phosphatases: molecular cloning and structural organization of the genes and immunolocalization of the proteins to plastids

The PPX/PP4 Ser/Thr protein phosphatases belong to the type 2A phosphatase subfamily and are present in most eukaryotic organisms. We have previously isolated two closely related DNAs encoding PPX isoforms (PPX-1 and PPX-2) of Arabidopsis thaliana. Here we report the molecular cloning of the genes encoding these proteins. The genes PPX-1 and PPX-2 are composed of eight exons and seven introns located at equivalent positions related to the coding sequences. Whereas the intron-exon organization of the PPX genes is completely different from that of the PP2A-3/PP2A-4 A. thaliana family, specific intron-exon boundaries are conserved among PPX genes from distantly related organisms. Based on GUS expression, both PPX genes show the same spatial and temporal pattern of expression: they are expressed in all the organs and tissues analyzed, and from the earliest stage of development. When PPX proteins were localized to the root in semi-thin methacrylate sections by immunofluorescence, staining was predominantly confined to small organelles, shown to be plastids by co-localization of PPX and ferredoxin. Interestingly, only some ferredoxin-positive plastids were also PPX-positive, and PPX staining was consistently brighter in the epidermis. The localization was confirmed with immunogold and electron microscopy. Our results suggest that, despite its strong sequence conservation, PPX in plants functions differently than in animals.     

Integrin α8β1 regulates adhesion,migration and proliferation of human intestinal crypt cells via a predominant RhoA/ROCK‐dependent mechanism

Background. Integrins are transmembrane αβ heterodimer receptors that function as structural and functional bridges between the cytoskeleton and ECM (extracellular matrix) molecules. The RGD (arginine‐glycine‐aspartate tripeptide motif)‐dependent integrin α8β1 has been shown to be involved in various cell functions in neuronal and mesenchymal‐derived cell types. Its role in epithelial cells remains unknown. Results. Integrin α8β1 was found to be expressed in the crypt cell population of the human intestine but was absent from differentiating and mature epithelial cells of the villus. The function of α8β1 in epithelial crypt cells was investigated at the cellular level using normal HIECs (human intestinal epithelial cells). Specific knockdown of α8 subunit expression using an shRNA (small‐hairpin RNA) approach showed that α8β1 plays important roles in RGD‐dependent cell adhesion, migration and proliferation via a RhoA/ROCK (Rho‐associated kinase)‐dependent mechanism as demonstrated by active RhoA quantification and pharmacological inhibition of ROCK. Moreover, loss of α8β1, through RhoA/ROCK, impairs FA (focal adhesion) complex integrity as demonstrated by faulty vinculin recruitment. Conclusions. Integrin α8β1 is expressed in epithelial cells. In intestinal crypt cells, α8β1 is closely involved in the regulation of adhesion, migration and cell proliferation via a predominant RhoA/ROCK‐dependent mechanism. These results suggest an important role for this integrin in intestinal crypt cell homoeostasis.     

Effects of fractionated x-irradiation on the Ly-6--Ril-1--Pol-5 region

Our laboratory has focused on defining, localizing, and understanding the mode of action of genes involved in fractionated x-irradiation (FXI) leukemia in susceptible and resistant mouse strains. We have described the genetic and molecular evidence suggesting the existence of multiple independent loci involved in FXI-induced leukemogenesis. These studies indicated that one of these, Ril-1, a locus on the distal portion of chromosome 15, is the major locus influencing susceptibility to the disease. Our data unequivocally place Ril-1 in the gene complex Ly-6--Ril-1--Sis--H-30--Pol-5. Ril-1 appears to be closest to Ly-6 and Sis. We report that in FXI-induced leukemias there are hypomethylation changes in the Ly-6 region as compared to normal thymocytes. In contrast, Sis was found to be hypermethylated and not expressed. In addition, we have noted DNA rearrangements in the Ly-6--Pol-5 region in the majority of tumors examined using the Ly-6 and spleen focus-forming virus (SFFLV) molecular probes. Increased expression of Ly-6 and other surface markers encoded in this region has been noted in FXI-induced thymomas. Address correspondence and offprint request to: N. M. B. Amari.     

The development of <Emphasis Type="Italic">Gymnophallus australis</Emphasis> Szidat, 1962 (Digenea: Gymnophallidae) from the Patagonian coast (Argentina) from metacercaria to adult,with an amended diagnosis of <Emphasis Type="Italic">Gymnophallus</Emphasis> Odhner, 1905

Parvatrema australis (Szidat, 1962) Szidat, 1965 was described based on larval stages found in specimens of the mussel Mytilus edulis from the Buenos Aires Province, Argentina. Although Szidat later examined hundreds of mussels, this parasite has never been found again until now. In the present study, larval stages, including germinal sacs, found in mytilids from the Patagonian coast were identified as P. australis. Metacercariae were incubated in vitro at 39 degrees C in physiological solution for 18-20 hours, by which time 80% of the specimens had eggs. P. australis is redescribed, on the basis of infective metacercariae and adults obtained in the laboratory, and is reassigned to Gymnophallus Odhner, 1900, the genus in which it was originally described. The generic diagnosis of Gymnophallus is here amended to include as diagnostic characters the presence or absence of the lateral lips, the form and position of the vitellarium (compact or follicular) and the presence of a pars prostatica (i.e. prostatic cells open into proximal part of the ejaculatory duct). The validity of some characters (i.e. the presence of lateral lips of the oral sucker, the form of the vitellarium and excretory vesicle, the extent of the uterus) as diagnostic at the generic level within the family Gymnophallidae is discussed. It is proposed that the least unambiguous characters that can be used to distinguish gymnophallid genera include the position of the ovary, the presence of a ventral pit and a pars prostatica, and caecal diverticula.     

Coenzyme Q10 deficiency in mitochondrial DNA depletion syndromes

We evaluated coenzyme Q₁₀ (CoQ) levels in patients studied under suspicion of mitochondrial DNA depletion syndromes (MDS) (n = 39). CoQ levels were quantified by HPLC, and the percentage of mtDNA depletion by quantitative real-time PCR. A high percentage of MDS patients presented with CoQ deficiency as compared to other mitochondrial patients (Mann–Whitney-U test: p = 0.001). Our findings suggest that MDS are frequently associated with CoQ deficiency, as a possible secondary consequence of disease pathophysiology. Assessment of muscle CoQ status seems advisable in MDS patients since the possibility of CoQ supplementation may then be considered as a candidate therapy.