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Background Donor and recipient age may have an impact on the renal transplant outcome. Kidney transplantation from older donors may result in a worse outcome, and the survival benefit of kidney transplantation compared with dialysis may be reduced. The aim of this study was to evaluate the impact of donor and recipient age on kidney transplant outcome. Materials and methods Two hundred and twenty-three recipients of kidney transplants performed at our institution between 2002 and 2007 were analysed. The role of donor and recipient age matching on survival rate were investigated performing the Kaplan-Meier survival time analysis by decades, considering the donor's age of 60 and 70 years. The Cox proportional hazard uni- and multivariate regressions were also performed. Finally, Kaplan-Meier survival time analysis was performed to assess survival rates of patients transplanted stratified by donor age compared with wait-listed renal transplant candidates. Results Elderly recipients had a significant lower graft and patient survival as well as a significantly higher risk of graft loss and patient death. Recipients younger and older than 65 years of age were at higher risk of graft loss if they received grafts from donors>65 years [hazard ratio (HR)=2.59, 95% confidence interval (CI): 1.12-6 and HR=5.65, 95% CI: 2.31-13.79, respectively]. Elderly recipients displayed a worse survival compared with transplant candidates on the waiting list. Conclusions Age is an important predictor of kidney transplantation outcome. Kidney transplantation does not offer a significant survival benefit in the intermediate term, compared to the waiting list, to elderly recipients transplanted with grafts from older donors. However, it cannot be excluded that it is still possible that there is a long-term benefit of transplantation over dialysis in this group of patients.

Background Nonimmunologic factors have been recently implicated in worse outcomes after kidney transplantation, producing a need to predict the operative risk among kidney recipients. We assessed the predictive value of the Charlson comorbidity index (CCI) among kidney transplant recipients. Methods A retrospective study of 223 first deceased-donor kidney transplantations performed from 2000 to 2007 evaluated the role of comorbidities. Results About 50% of recipients displayed >1 comorbid condition before transplantation; the most frequently reported was diabetes mellitus. Increasing CCI scores significantly affected graft and patient survivals. Crude analysis showed a significant association between CCI >1 and risk of death (hazard ratio [HR], 3.87; 95% confidence interval [CI], 1.06–14.06; P = .04). After adjustment for several covariates, high CCI values remained significantly predictive of posttransplantation outcomes with a HR for death of (12.53; 95% CI, 1.9–82.68; P = .009). Conclusions Our predictive model showed a strong association of CCI and patient survival even after adjustment for several clinical covariates. CCI may be used to evaluate patients referred for kidney transplantation who display a significant burden of comorbid conditions that increase the risk of premature death or graft loss.

Background There are still many controversies about the impact of delayed graft function (DGF) on kidney transplantation outcome. The aims of this study were to define factors associated with DGF and to ascertain the relative impact of DGF on kidney transplantation outcome, both in the early postoperative period and in long-term follow-up. Patients and Methods Four hundred kidney transplant recipients were reviewed to assess the clinical impact of DGF on long-term outcome. Results The overall prevalence of DGF was 24.3%. DGF was significantly associated with increasing recipient and donor age, duration of dialysis, and cold ischemia time. Patients with DGF displayed a significantly worse graft ( P = .005) and patient ( P Conclusion DGF is a frequent complication of renal transplantation and may be associated with a reduced graft and even patient survival. Strategies to prevent graft injury and, more specifically, DGF may be an important clue to provide a better long-term outcome in kidney transplantation.

Epigenetics is the study of hereditable chromatin modifications, such as DNA methylation, histone modifications, and nucleosome-remodelling, which occur without alterations to the DNA sequence. The establishment of different epigenetic states in eukaryotes depends on regulatory mechanisms that induce structural changes in chromatin in response to environmental and cellular cues. Two classes of enzymes modulate chromatin accessibility: chromatin-covalent modifiers and ATP-dependent chromatin remodelling complexes. The first class of enzymes catalyzes covalent modifications of DNA as well as the amino- and carboxy-terminal tails of histones, while the second uses the energy of ATP hydrolysis to reposition nucleosomes along the chromatin fibers or to incorporate histone variants. Thus, epigenetic modifications are reversible nuclear reactions. In the last decade, many studies have strongly indicated that alterations in epigenetic modifications may contribute to the onset and progression of a variety of human diseases such as cancer. Therefore, the enzymes responsible for these chromatin changes are becoming attractive therapeutic targets.

The basic unit of eukaryotic chromatin is the nucleosome, consisting of about 150 bp of DNA wrapped around a protein core made of histone proteins. Nucleosomes position is modulated in vivo to regulate fundamental nuclear processes. To measure nucleosome positions on a genomic scale both theoretical and experimental approaches have been recently reported. We have developed a new method, Multi-Layer Model (MLM), for the analysis of nucleosome position data obtained with microarray-based approach. The MLM is a feature extraction method in which the input data is processed by a classifier to distinguish between several kinds of patterns. We applied our method to simulated-synthetic and experimental nucleosome position data and found that besides a high nucleosome recognition and a strong agreement with standard statistical methods, the MLM can identify distinct classes of nucleosomes, making it an important tool for the genome wide analysis of nucleosome position and function. In conclusion, the MLM allows a better representation of nucleosome position data and a significant reduction in computational time.

The management of Crohn's disease (CD) requires extensive expertise. Many treatment options are available, and surgery still plays a crucial role. In recent years, many medical societies have provided surgeons and gastroenterologists dealing with CD with authoritative guidelines. However, a certain degree of variation can be observed in these papers, and application of guidelines in clinical practice should be improved. The Italian society of colorectal surgery (SICCR) promoted the project reported here, which consists of a think tank of Italian colorectal surgeons to address the surgical aspects of CD management. Members of the society were invited to express their opinions on several items proposed by the writing committee, based on evidence available in the literature. The results are presented, focusing on relevant points. The present paper is not an alternative to available guidelines; rather, it offers a snapshot of the attitudes of SICCR surgeons about the surgical treatment of CD. The management of CD is, by necessity, patient-tailored, and it is based on clinical data and surgeon's preference, but the committee was able to identify some points of major disagreement and suggested strategies to improve quality of available data and acceptance of guidelines. The management of Crohn’s disease (CD) requires extensive expertise. Many treatment options are available, and surgery still plays a crucial role. In recent years, many medical societies have provided surgeons and gastroenterologists dealing with CD with authoritative guidelines. However, a certain degree of variation can be observed in these papers, and application of guidelines in clinical practice should be improved. The Italian society of colorectal surgery (SICCR) promoted the project reported here, which consists of a think tank of Italian colorectal surgeons to address the surgical aspects of CD management. Members of the society were invited to express their opinions on several items proposed by the writing committee, based on evidence available in the literature. The results are presented, focusing on relevant points. The present paper is not an alternative to available guidelines; rather, it offers a snapshot of the attitudes of SICCR surgeons about the surgical treatment of CD. The management of CD is, by necessity, patient-tailored, and it is based on clinical data and surgeon’s preference, but the committee was able to identify some points of major disagreement and suggested strategies to improve quality of available data and acceptance of guidelines.

The majority of patients suffering from ulcerative colitis (UC) are managed successfully with medical treatment, but a relevant number of them will still need surgery at some point in their life. Medical treatments and surgical techniques have changed dramatically in recent years, and available guidelines from relevant societies are rapidly evolving, providing UC experts with updated and valid practical recommendations. However, some aspects of the management of UC patients are still debated, and the application of guidelines in clinical practice may be suboptimal. The Italian Society of Colorectal Surgery (SICCR) sponsored the think tank in order to identify critical aspects of the surgical management of UC in Italy. The present paper reports the results of a think tank of Italian colorectal surgeons concerning surgery for UC and was not developed as an alternative to authoritative guidelines currently available. Members of the SICCR voted on several items proposed by the writing committee, based on evidence from the literature. The results are presented, focusing on points to be implemented. UC management relies on evaluations that need to be individualized, but points of major disagreement reported in this paper should be considered in order to develop strategies to improve the quality of the evidence and the application of guidelines in a clinical setting.

The packaging of the eukaryotic genome into chromatin facilitates the storage of the genetic information within the nucleus, but prevents the access to the underlying DNA sequences. Structural changes in chromatin are mediated by several mechanisms. Among them, ATP-dependent remodelling complexes belonging to ISWI family provides one of the best examples that eukaryotic cells evolved to finely regulate these changes. ISWI-containing complexes use the energy derived from ATP hydrolysis to rearrange nucleosomes on chromatin in order to favour specific nuclear reactions. The combination of regulatory nuclear factors associated with the ATPase subunit as well as its modulation by specific histone modifications, specializes the nuclear function of each ISWI-containing complex. Here we review the different ways by which ISWI enzymatic activity can be modulated and regulated in the nucleus of eukaryotic cells.

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant myopathy with a strong epigenetic component. It is associated with deletion of a macrosatellite repeat leading to over-expression of the nearby genes. Among them, we focused on FSHD region gene 1 (FRG1) since its over-expression in mice, Xenopus laevis and Caenorhabditis elegans, leads to muscular dystrophy-like defects, suggesting that FRG1 plays a relevant role in muscle biology. Here we show that, when over-expressed, FRG1 binds and interferes with the activity of the histone methyltransferase Suv4-20h1 both in mammals and Drosophila. Accordingly, FRG1 over-expression or Suv4-20h1 knockdown inhibits myogenesis. Moreover, Suv4-20h KO mice develop muscular dystrophy signs. Finally, we identify the FRG1/Suv4-20h1 target Eid3 as a novel myogenic inhibitor that contributes to the muscle differentiation defects. Our study suggests a novel role of FRG1 as epigenetic regulator of muscle differentiation and indicates that Suv4-20h1 has a gene-specific function in myogenesis.

BACKGROUND: In a previous work we showed for the first time that human tumor cells secrete Hsp60 via exosomes, which are considered immunologically active microvesicles involved in tumor progression. This finding raised questions concerning the route followed by Hsp60 to reach the exosomes, its location in them, and whether Hsp60 can be secreted also via other mechanisms, e.g., by the Golgi. We addressed these issues in the work presented here. PRINCIPAL FINDINGS: We found that Hsp60 localizes in the tumor cell plasma membrane, is associated with lipid rafts, and ends up in the exosomal membrane. We also found evidence that Hsp60 localizes in the Golgi apparatus and its secretion is prevented by an inhibitor of this organelle. CONCLUSIONS/SIGNIFICANCE: We propose a multistage process for the translocation of Hsp60 from the inside to the outside of the cell that includes a combination of protein traffic pathways and, ultimately, presence of the chaperonin in the circulating blood. The new information presented should help in designing future strategies for research and for developing diagnostic-monitoring means useful in clinical oncology.

The eukaryotic genome is a highly organized nucleoprotein structure comprising of DNA, histones, non-histone proteins, and RNAs, referred to as chromatin. The chromatin exists as a dynamic entity, shuttling between the open and closed forms at specific nuclear regions and loci based on the requirement of the cell. This dynamicity is essential for the various DNA-templated phenomena like transcription, replication, and repair and is achieved through the activity of ATP-dependent chromatin remodeling complexes and covalent modifiers of chromatin. A growing body of data indicates that chromatin enzymatic activities are finely and specifically regulated by a variety of small molecules derived from the intermediary metabolism. This review tries to summarize the work conducted in many laboratories and on different model organisms showing how ATP-dependent chromatin remodeling complexes are regulated by small molecules and metabolites such as adenosine triphosphate (ATP), acetyl coenzyme A (AcCoA), S-adenosyl methionine (SAM), nicotinamide adenine dinucleotide (NAD), and inositol polyphosphates (IPs).

Background Hsp60, a Group I mitochondrial chaperonin, is classically considered an intracellular chaperone with residence in the mitochondria; nonetheless, in the last few years it has been found extracellularly as well as in the cell membrane. Important questions remain pertaining to extracellular Hsp60 such as how generalized is its occurrence outside cells, what are its extracellular functions and the translocation mechanisms that transport the chaperone outside of the cell. These questions are particularly relevant for cancer biology since it is believed that extracellular chaperones, like Hsp70, may play an active role in tumor growth and dissemination. Methodology/Principal Findings Since cancer cells may undergo necrosis and apoptosis, it could be possible that extracellular Hsps are chiefly the result of cell destruction but not the product of an active, physiological process. In this work, we studied three tumor cells lines and found that they all release Hsp60 into the culture media by an active mechanism independently of cell death. Biochemical analyses of one of the cell lines revealed that Hsp60 secretion was significantly reduced, by inhibitors of exosomes and lipid rafts. Conclusions/Significance Our data suggest that Hsp60 release is the result of an active secretion mechanism and, since extracellular release of the chaperone was demonstrated in all tumor cell lines investigated, our observations most likely reflect a general physiological phenomenon, occurring in many tumors.

Histone acetylation plays essential roles in cell cycle progression, DNA repair, gene expression and silencing. Although the knowledge regarding the roles of acetylation of histone lysine residues is rapidly growing, very little is known about the biochemical pathways providing the nucleus with metabolites necessary for physiological chromatin acetylation. Here, we show that mutations in the scheggia (sea)-encoded Sea protein, the Drosophila ortholog of the human mitochondrial citrate carrier Solute carrier 25 A1 (SLC25A1), impair citrate transport from mitochondria to the cytosol. Interestingly, inhibition of sea expression results in extensive chromosome breakage in mitotic cells and induces an ATR-dependent cell cycle arrest associated with a dramatic reduction of global histone acetylation. Notably, loss of SLC25A1 in short interfering RNA (siRNA)-treated human primary fibroblasts also leads to chromosome breaks and histone acetylation defects, suggesting an evolutionary conserved role for Sea/SLC25A1 in the regulation of chromosome integrity. This study therefore provides an intriguing and unexpected link between intermediary metabolism and epigenetic control of genome stability.

ISWI functions as the ATPase subunit of multiple chromatin-remodeling complexes. These complexes use the energy of ATP hydrolysis to slide nucleosomes and increase chromatin fluidity, thereby modulating the access of transcription factors and other regulatory proteins to DNA. Here we discuss recent progress toward understanding the biological functions of ISWI, with an emphasis on its roles in transcription, chromosome organization and DNA replication.

Heat-shock protein (Hsp)10 is the co-chaperone for Hsp60 inside mitochondria, but it also resides outside the organelle. Variations in its levels and intracellular distribution have been documented in pathological conditions, e.g. cancer and chronic obstructive pulmonary disease (COPD). Here, we show that Hsp10 in COPD undergoes changes at the molecular and subcellular levels in bronchial cells from human specimens and derived cell lines, intact or subjected to stress induced by cigarette smoke extract (CSE). Noteworthy findings are: (i) Hsp10 occurred in nuclei of epithelial and lamina propria cells of bronchial mucosa from non-smokers and smokers; (ii) human bronchial epithelial (16HBE) and lung fibroblast (HFL-1) cells,in vitro, showed Hsp10 in the nucleus, before and after CSE exposure; (iii) CSE stimulation did not increase the levels of Hsp10 but did elicit qualitative changes as indicated by molecular weight and isoelectric point shifts; and (iv) Hsp10 nuclear levels increased after CSE stimulation in HFL-1, indicating cytosol to nucleus migration, and although Hsp10 did not bind DNA, it bound a DNA-associated protein.

It has been established that Hsp60 can accumulate in the cytosol in various pathological conditions, including cancer and chronic inflammatory diseases. Part or all of the cytosolic Hsp60 could be naive, namely, bear the mitochondrial import signal (MIS), but neither the structure nor the in solution oligomeric organization of this cytosolic molecule has still been elucidated. Here we present a detailed study of the structure and self-organization of naive cytosolic Hsp60 in solution. Results were obtained by different biophysical methods (light and X ray scattering, single molecule spectroscopy and hydrodynamics) that all together allowed us to assay a wide range of concentrations of Hsp60. We found that Naive Hsp60 in aqueous solution is assembled in very stable heptamers and tetradecamers at all concentrations assayed, without any trace of monomer presence.