Heterochromatin protein 1 (HP1) is associated with induced gene expression in Drosophila euchromatin

Heterochromatin protein 1 (HP1) is a conserved nonhistone chromosomal protein, which is involved in heterochromatin formation and gene silencing in many organisms. In addition, it has been shown that HP1 is also involved in telomere capping in Drosophila. Here, we show a novel striking feature of this protein demonstrating its involvement in the activation of several euchromatic genes in Drosophila. By immunostaining experiments using an HP1 antibody, we found that HP1 is associated with developmental and heat shock–induced puffs on polytene chromosomes. Because the puffs are the cytological phenotype of intense gene activity, we did a detailed analysis of the heat shock–induced expression of the HSP70 encoding gene in larvae with different doses of HP1 and found that HP1 is positively involved in Hsp70 gene activity. These data significantly broaden the current views of the roles of HP1 in vivo by demonstrating that this protein has multifunctional roles

Sonohysterography and liquid-based cytology in menopausal patients with abnormal endometrium

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The Ribosomal Protein RpL22 Interacts In Vitro with 5′-UTR Sequences Found in Some Drosophila melanogaster Transposons

Mobility of eukaryotic transposable elements (TEs) are finely regulated to avoid an excessive mutational load caused by their movement. The transposition of retrotransposons is usually regulated through the interaction of host- and TE-encoded proteins, with non-coding regions (LTR and 5′-UTR) of the transposon. Examples of new potent cis-acting sequences, identified and characterized in the non-coding regions of retrotransposons, include the insulator of gypsy and Idefix, and the enhancer of ZAM of Drosophila melanogaster. Recently we have shown that in the 5′-UTR of the LTR-retrotransposon ZAM there is a sequence structured in tandem-repeat capable of operating as an insulator both in Drosophila (S2R+) and human cells (HEK293). Here, we test the hypothesis that tandem repeated 5′-UTR of a different LTR-retrotransposon could accommodate similar regulatory elements. The comparison of the 5′-UTR of some LTR-transposons allowed us to identify a shared motif of 13bp, called Transposable Element Redundant Motif (TERM). Surprisingly, we demonstrated, by Yeast One-Hybrid assay, that TERM interacts with the D. melanogaster ribosomal protein RpL22. The Drosophila RpL22 has additional Ala-, Lys- and Prorich sequences at the amino terminus, which resembles the carboxy-terminal portion of histone H1 and histone H5. For this reason, it has been hypothesized that RpL22 might have two functions, namely the role in organizing the ribosome, and a potential regulatory role involving DNA-binding similar to histone H1, which represses transcription in Drosophila. In this paper, we show, by two independent sets of experiments, that DmRpL22 is able to directly and specifically bind DNA of Drosophila melanogaster

The “Special” crystal-Stellate System in Drosophila melanogaster Reveals Mechanisms Underlying piRNA Pathway-Mediated Canalization

The Stellate-made crystals formation in spermatocytes is the phenotypic manifestation of a disrupted crystal-Stellate interaction in testes of Drosophila melanogaster. Stellate silencing is achieved by the piRNA pathway, but many features still remain unknown. Here we outline the important role of the crystal-Stellate modifiers. These have shed light on the piRNA pathways that defend genome integrity against transposons and other repetitive elements in the gonads. In particular, we illustrate the finding that HSP90 participates in the molecular pathways of piRNA production. This observation has relevance for the mechanisms underlying the evolutionary canalization process

Laparoscopy in liver transplantation: The future has arrived

In the last two decades, laparoscopy has revolutionized the field of surgery. Many procedures previously performed with an open access are now routinely carried out with the laparoscopic approach. Several advantages are associated with laparoscopic surgery compared to open procedures: reduced pain due to smaller incisions and hemorrhaging, shorter hospital length of stay, and a lower incidence of wound infections. Liver transplantation (LT) brought a radical change in life expectancy of patients with hepatic endstage disease. Today, LT represents the standard of care for more than fifty hepatic pathologies, with excellent results in terms of survival. Surely, with laparoscopy and LT being one of the most continuously evolving challenges in medicine, their recent combination has represented an astonishing scientific progress. The intent of the present paper is to underline the current role of diagnostic and therapeutic laparoscopy in patients waiting for LT, in the living donor LT and in LT recipients

The DNA polymerases of Drosophila melanogaster.

DNA synthesis during replication or repair is a fundamental cellular process that is catalyzed by a set of evolutionary conserved polymerases. Despite a large body of research, the DNA polymerases of Drosophila melanogaster have not yet been systematically reviewed, leading to inconsistencies in their nomenclature, shortcomings in their functional (Gene Ontology, GO) annotations and an under-appreciation of the extent of their characterization. Here, we describe the complete set of DNA polymerases in D. melanogaster, applying nomenclature already in widespread use in other species, and improving their functional annotation. A total of 19 genes encode the proteins comprising three replicative polymerases (alpha-primase, delta, epsilon), five translesion/repair polymerases (zeta, eta, iota, Rev1, theta) and the mitochondrial polymerase (gamma). We also provide an overview of the biochemical and genetic characterization of these factors in D. melanogaster. This work, together with the incorporation of the improved nomenclature and GO annotation into key biological databases, including FlyBase and UniProtKB, will greatly facilitate access to information about these important proteins

Detection of Alkaline Sphingomyelinase Activity in Human Stool: Proposed Role as a New Diagnostic and Prognostic Marker of Colorectal Cancer

Abstract Objectives: Intestinal alkaline sphingomyelinase, by exerting a major role in dietary sphingomyelin digestion, is responsible for the generation of messengers able to trigger the rapid turnover and apoptosis in intestinal epithelial cells. Markedly reduced mucosal alkaline sphingomyelinase activity has been associated with human colorectal neoplasms. The aim of this study was to analyze the alkaline sphingomyelinase activity in feces from healthy subjects and colorectal adenocarcinoma patients and to correlate it with the enzyme activity in intestinal tissues. Materials and Methods: The enzyme activity was measured both in the intestinal samples from 12 healthy controls and 51 patients with colorectal adenocarcinoma (tumoral and paratumoral tissue) and in the fecal samples of 34 healthy subjects and 29 patients with adenocarcinoma. The relation between sphingomyelinase activity and Dukes' stage, cell differentiation degree, age, and gender was also analyzed. Results: Alkaline sphingomyelinase was significantly decreased (P < 0.001; mean reduction >90%) in tumoral intestinal mucosa of patients compared with controls independently of Dukes' stage and tumor differentiation grade. Interestingly, the enzyme activity in histologically normal paratumoral tissues was statistically lower than control samples (P < 0.001). As occurs in neoplastic tissues, a relevant mean reduction (P < 0.0001; almost 90%) of alkaline sphingomyelinase was revealed in stool samples from tumor patients when compared with controls. Conclusion: These findings may have implications for cancer biology and perhaps also for the design of clinical test, thus suggesting that the fecal sphingomyelinase activity could really reflect the human intestinal mucosa enzyme level and could represent a new marker for human colorectal adenocarcinoma, mainly taking into account its early appearance in intestinal neoplasms

Alpha-SMA expression in hepatic stellate cells and quantitative analysis of hepatic fibrosis in cirrhosis and in recurrent chronic hepatitis after liver transplantation

Background. The alpha isotype of actin expressed by hepatic stellate cells reflects their activation to myofibroblast-like cell and has been directly related to experimental liver fibrogenesis, and indirectly to human fibrosis in chronic liver disease. Aims. To evaluate the changes in distribution and percentage of alpha-smooth muscle actin-positive hepatic stellate cells and the correlation with the degree of the fibrosis in cirrhotic livers, as well as in patients with recurrent HCV chronic hepatitis after liver transplantation. Methods. Human liver biopsies were divided in four groups: (1) normal livers obtained from cadaveric liver donors (n = 35), (2) cirrhosis post-HBV hepatitis (n = 11), (3) cirrhosis post-HCV hepatitis (n = 10), and (4) post-transplant recurrent HCV chronic hepatitis (n = 13). Samples were stained with anti-alpha-smooth muscle actin antibody by immunoperoxidase method and semi-quantitatively evaluated. Liver fibrosis was assessed from specimens stained with Masson's trichrome and quantified by computer image analysis. Results. The percentage of alpha-smooth muscle actin-positive hepatic stellate cells was significantly higher in the HBV cirrhosis, HCV cirrhosis and post-transplant HCV recurrent hepatitis groups (36.1 +/- 15.2, 23.8 +/- 19.7 and 27.8 +/- 16.4%, respectively) compared to the liver donor group (2.9 +/- 4.0%). The alpha-smooth muscle actin-positive hepatic stellate cells to fibrous tissue ratio were significantly higher in the post-transplant recurrent HCV hepatitis group (2.36 +/- 1.12) compared to both the donor livers and the HCV cirrhosis groups (0.74 +/- 1.09 and 1.03 +/- 0.91, respectively). The alpha-smooth muscle actin-positive hepatic stellate cell percentage and fibrosis correlated positively in the post-transplant recurrent HCV hepatitis group and negatively in the HCV cirrhosis group. No difference in the immunohistochemical and morphometrical variables was found between the HCV cirrhosis and HBV cirrhosis groups. Conclusions. These results indirectly confirm that, in vivo, alpha-smooth muscle actin expression is a reliable marker of hepatic stellate cells activation which precedes fibrous tissue deposition even in the setting of recurrent HCV chronic hepatitis after liver transplantation, and it could be useful to identify the earliest stages of hepatic fibrosis and monitoring the efficacy of the therapy. In the presence of advanced cirrhosis other factors, rather than alpha-smooth muscle actin-positive hepatic stellate cells, may sustain fibrosis deposition. (c) 2005 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved

Selection of potential probiotic lactobacilli from pig feces to be used as additives in pelleted feeding,”

Abstract Thirty-five isolates from pig feces were identified as Lactobacillus reuteri (12 strains), Lactobacillus mucosae (7), Lactobacillus plantarum (6), Lactobacillus kitasatonis (3), Lactobacillus rossiae (2), Lactobacillus ultunensis (2), Lactobacillus crispatus (2), and Lactobacillus intestinalis (1) by partial sequence analysis of the 16S rRNA. All isolates were detected at 8-9 log CFU g −1 . Preliminarily, strains were selected based on resistance to heat treatments (ca. 70 • C for 10 s). The decrease in viability for some L. reuteri, L. mucosae, L. plantarum, L. kitasatonis, and L. rossiae strains was lower than 1 log cycle. Selected strains were further characterized for acid and bile salt resistance, and antibacterial activity. Except for L. kitasatonis, tolerance to simulated gastric and intestinal conditions was enhanced for all strains by addition of reconstituted skimmed milk. Antibacterial activity was found against Gram-positive and -negative potential pathogens. L. reuteri 8.1, 3S7, 6.2, and 1.2, L. mucosae 1.1R, L. plantarum 4.1, and L. rossiae 4.4 were freeze-dried and mixed (1%, w/w) into pig feed before pelleting. After pelleting, pig feed contained 10-9 log CFU kg −1 of lactobacilli. L. plantarum 4.1, and L. reuteri 3S7 were selected based on their bile salt resistance, pH tolerance, antimicrobial activity and heat resistance. The findings in this study provide a strong basis for exploring the potential of porcine lactobacilli isolates to be used in pelleted feeding as probiotic additives