GTP modulates calcium binding and cation-induced conformational changes in erythrocyte transglutaminase

AbstractCalcium binding to erythrocyte transglutaminase was determined by equilibrium dialysis. Results indicate that 6 ions are bound to the enzyme both in the absence and in the presence of GTP and. that the nucleotide reduces the affinity of the enzyme for calcium. Furthermore, I− fluorescence quenching and proteolytic inactivation experiments proved that GTP also alters the conformation of the enzyme. It is thus suggested that multiple mechanisms are involved in the regulation of the enzyme activity by GTP

Proteomics Disclose the Potential of Gingival Crevicular Fluid (GCF) as a Source of Biomarkers for Severe Periodontitis

: Periodontal disease is a widespread disorder comprising gingivitis, a mild early gum inflammation, and periodontitis, a more severe multifactorial inflammatory disease that, if left untreated, can lead to the gradual destruction of the tooth-supporting apparatus. To date, effective etiopathogenetic models fully explaining the clinical features of periodontal disease are not available. Obviously, a better understanding of periodontal disease could facilitate its diagnosis and improve its treatment. The purpose of this study was to employ a proteomic approach to analyze the gingival crevicular fluid (GCF) of patients with severe periodontitis, in search of potential biomarkers. GCF samples, collected from both periodontally healthy sites (H-GCF) and the periodontal pocket (D-GCF), were subjected to a comparison analysis using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). A total of 26 significantly different proteins, 14 up-regulated and 12 down-regulated in D-GCF vs. H-GCF, were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The main expressed proteins were inflammatory molecules, immune responders, and host enzymes. Most of these proteins were functionally connected using the STRING analysis database. Once validated in a large scale-study, these proteins could represent a cluster of promising biomarkers capable of making a valuable contribution for a better assessment of periodontitis

Changes in protein expression in two cholangiocarcinoma cell lines undergoing formation of multicellular tumor spheroids In vitro

Epithelial-to-Mesenchymal Transition (EMT) is relevant in malignant growth and frequently correlates with worsening disease progression due to its implications in metastases and re- sistance to therapeutic interventions. Although EMT is known to occur in several types of solid tumors, the information concerning tumors arising from the epithelia of the bile tract is still limited. In order to approach the problem of EMT in cholangiocarcinoma, we decided to investigate the changes in protein expression occurring in two cell lines under conditions leading to growth as adherent monolayers or to formation of multicellular tumor spheroids (MCTS), which are considered culture models that better mimic the growth characteristics of in-vivo solid tumors. In our system, changes in phenotypes occur with only a decrease in transmembrane E-cadherin and vimentin expression, minor changes in the transglutami- nase protein/activity but with significant differences in the proteome profiles, with declining and increasing expression in 6 and in 16 proteins identified by mass spectrometry. The aris- ing protein patterns were analyzed based on canonical pathways and network analysis. These results suggest that significant metabolic rearrangements occur during the conver- sion of cholangiocarcinomas cells to the MCTS phenotype, which most likely affect the car- bohydrate metabolism, protein folding, cytoskeletal activity, and tissue sensitivity to oxygen

A Proteomic Analysis of Discolored Tooth Surfaces after the Use of 0.12% Chlorhexidine (CHX) Mouthwash and CHX Provided with an Anti-Discoloration System (ADS)

Chlorhexidine (CHX) is considered the gold standard for the chemical control of bacterial plaque and is often used after surgical treatment. However, CHX employment over an extended time is responsible for side effects such as the appearance of pigmentations on the teeth and tongue; the discoloration effects are less pronounced when using a CHX-based mouthwash with added an anti-discoloration system (ADS). The aim of this study was to evaluate, using one- and two-dimensional gel electrophoresis combined with mass spectrometry, the possible proteomic changes induced by CHX and CHX+ADS in the supragingival dental sites susceptible to a discoloration effect. The tooth surface collected material (TSCM) was obtained by curettage after resective bone surgery from three groups of patients following a supportive therapy protocol in which a mechanical control was combined with placebo rinses or CHX or a CHX+ADS mouthwash. The proteomic analysis was performed before surgery (basal conditions) and four weeks after surgery when CHX was used (or not) as chemical plaque control. Changes in the TSCM proteome were only revealed following CHX treatment: glycolytic enzymes, molecular chaperones and elongation factors were identified as more expressed. These changes were not detected after CHX+ADS treatment. An ADS could directly limit TSCM forming and also the CHX antiseptic effect reduces its ability to alter bacterial cell permeability. However, Maillard's reaction produces high molecular weight molecules that change the surface properties and could facilitate bacterial adhesion

The comparison of the proteomic profile of periodontal pocket and of corresponding gingival crevicular fluid to study periodontal disease biomarkers: feasibility study. biomarkers: feasibility study

Aim: Periodontitis is a set of inflammatory disorders characterized by periodontal attachment loss by periodontal pocket development, leading to tooth loss if remain untreated. The etiology and progress of periodontal disease is complex and remains mostly unknown. So, periodontal disease therapy has considerable limitations. The easy, reliable and correct early detection and control of the disease, markedly reduces biological and social costs. However, the diagnosis of periodontitis is established exclusively by clinical criteria based on probing to assess periodontal pockets, which are the pathognomonic expression of periodontal disease. The -omic sciences acquired substantial significance of late years and, in particular, proteomic seemed to be the more promising in this initial stage. Most proteomic analysis regarding periodontal diseases have been performed on saliva, crevicular fluid samples, peripheral blood or periodontal plaque samples which are more easily to harvest than the tissue of the periodontal pocket. However, they failed to provide reliable results for clinical applications. On the contrary, very few studies were directly performed on the periodontal pocket. So, the aim of this study was to compare the proteomic profile of interproximal pocket tissues with that of GCF, and to analyze if they show a significant similarity in the proteomic profile. Methods: in this preliminary study, we enrolled 3 healthy subjects affected by severe periodontitis needing of periodontal surgery. Immediately before the surgery, GCF samples were taken by means of filter paper strips positioned in the gingival sulcus correspondent to periodontal pockets. Then, periodontal pocket tissue, harvested during surgery, was adequately stored for proteomic analyses. All samples were immediately frozen at \u201380\ub0C and maintained until further analysis. Tissue samples were mechanically disrupted and incubated in lysis buffer, while GCF was obtained incubating the collecting paper in phosphate buffered. In both cases, after centrifugation, the supernatant was precipitated in cold acetone overnight and protein content were pelleted by centrifugation and then dissolved in a rehydration buffer. Mono-dimensional gel electrophoresis was used to separate protein content. After staining gel images were acquired and compared. Liquid chromatography coupled to mass spectrometry (LC-MS/MS) analysis was performed to allow protein spot identification. Results: 1-DE gels from periodontal pocket tissue and the correspondent GCF was analyzed by software Quantity One. Almost the same qualitative protein expression profile in pocket tissue and GCF was found from each patient. However, no statistical significant correlation between the quantitative proteomic profile of pocket tissue and GCF was found. Only one band (that of K immunoglobulin) resulted statistically significant between GCF and pocket tissue proteome in all patients. Conclusions To date, this is the first study comparing the proteome of periodontal pocket tissue and corresponding GCF. The periodontal pocket and the GCF are similar as proteomic networks, but the protein network of the periodontal pocket does not influence significantly the GCF protein network and the other way around. So, with the limitations of this study, the preliminary results seem to indicate that the GCF does not seem suitable to study on the pathogenesis of periodontal disease explaining the reason for the failure of studies based only on GCF to control the periodontal disease in real-time

Safety and efficacy of tranexamic acid for prevention of obstetric haemorrhage. An updated systematic review and meta-analysis

Background. A number of clinical systematic review and meta-analysis have been published on the use of tranexamic in the obstetric setting. The aim of this meta-analysis was to evaluate the safety and effectiveness of tranexamic acid in reducing blood loss when given prior to caesarean delivery. Materials and methods. We searched the Cochrane Wounds Specialized Register, Cochrane Central, MEDLINE (through PUBMED), Embase, and SCOPUS electronic databases. We also searched clinical trials registries for ongoing and unpublished studies, and checked reference lists to identify additional studies. We used no restrictions with respect to language and date of publication. Two review authors independently performed study selection, "Risk of bias" assessment, and data extraction. Initial disagreements were resolved by discussion, or by including a third review author when necessary. Results. We found 18 randomised controlled trials (RCTs) that met our inclusion criteria. Overall, 1,764 women receiving intravenous tranexamic acid for prevention of bleeding following caesarean sections and 1,793 controls receiving placebo were enrolled in the 18 RCTs evaluated. The use of tranexamic acid compared to controls (placebo or no intervention) reduces post-partum haemorrhage >400 mL (risk ratio [RR] 0.40, 95% confidence interval [CI] 0.24-0.65; 5 trials with a total of 786 participants), severe post-partum haemorrhage >1,000 mL (RR 0.32, 95% CI: 0.12-0.84; 5 trials with a total of 1,850 participants), and need for red blood cell transfusion (RR 0.30, 95% CI: 0.18-0.49; 10 trials with a total of 1,873 participants). No particular safety concerns on the use of this antifibrinolytic agent emerged from the analysis of the 18 RCTs included. Discussion. Overall, the results of this meta-analysis support the evidence of a beneficial effect of tranexamic acid in reducing blood loss and need for blood transfusion in pregnant women undergoing caesarean section

Oxidative stress and menopause-related hot flashes may be independent events.

Abstract Objective At present, there is growing demand for alternative, or additional, treatments to hormone replacement therapy for menopause-related hot flashes (HF). Antioxidant supplements have been recently proposed as possible candidates for this purpose, regardless of the absence of clear evidence in support of a link between these vasomotor symptoms and oxidative stress (OxS). The aim of our study was to evaluate the association between HF and OxS serum markers in a large sample of middle-aged women. Materials and methods We conducted a cross-sectional study on 245 perimenopausal and early postmenopausal women (age 45–60 years). The variables examined were presence of self-reported HF and levels of 8-iso-prostaglandin F2α, 8-OH-deoxy-2′-guanosine, advanced oxidation protein products, total antioxidant power, uric acid, thiols, and paroxonase-1. Results Seventy-six women (31%) reported to suffer from HF (either medium or high intensity). None of the peripheral markers of OxS examined was found to be significantly associated with the presence of HF. Conclusion Taken together, our data suggest that systemic OxS might not be implicated with the onset of the climacteric vasomotor symptoms that most commonly affect women experiencing perimenopause and early postmenopause

Gonadal Function in Male Patients With Metastatic Renal Cell Cancer Treated With Sunitinib

Background/aim: Single-agent tyrosine kinase inhibitors are still prescribed as first-line treatment to a relevant subgroup of patients with metastatic renal cell carcinoma (mRCC). These agents are known to cause disfunction of many endocrine glands (e.g., thyroid). In this two-step trial, we aimed to assess gonadal function among male patients with mRCC treated with sunitinib. Patients and methods: We enrolled a first cross-sectional cohort of pre-treated (>6 months) patients and a subsequent cohort of treatment-naïve patients who were prospectively followed-up. All patients were screened for hypogonadism and received a Functional Assessment of Cancer Therapy - General (FACT-G) questionnaire at study entry and after 6 months of therapy. Patients who were candidates for testosterone replacement therapy (TRT) also received a FACT-G questionnaire at baseline and 3 months after supplementation. Results: Among the 30 enrolled patients, the prevalence of hypogonadism was found to be higher in those receiving sunitinib for a longer period (27.3% at baseline, 41.7% in the first 6 months, and 68.4% after 9 months of therapy). The testosterone level of patients correlated with quality of life (R=0.32). A total of six patients received TRT, with a significant improvement in their global quality of life after the first 3 months of treatment. Conclusion: An increasing prevalence of hypogonadism was seen among male patients who received long-term treatment with sunitinib. TRT was associated with relevant improvements in quality of life. These findings corroborate similar published observations and encourage the assessment of gonadal function in male patients with mRCC under treatment with sunitinib