Endosseous dental implant fractures an analysis of 21 cases

Implant fracture is an infrequent cause of implant failure. The present study evaluates 21 fractured implants, with an analysis of patient age and sex, the type, length and diameter of the implant, positioning in the dental arch, the type of prosthetic rehabilitation involved, the number of abutments and pontics, the presence or absence of distal extensions or cantilevers, and loading time to fracture. Implant fracture was more common in males than in females (15:4), and the mean patient age was 56.9 years. Most cases (n = 19) corresponded to implant-supported fixed prostheses - 16 with cantilevers of different lengths ? while only two fractured implants were supporting overdentures instead of fixed prostheses. The great majority of fractured implants (80.9%) were located in the molar and premolar regions, and most fractured within 3-4 years after loading. It is important to know and apply the measures required to prevent implant fracture, and to seek the best individualized solution for each case - though complete implant removal is usually the treatment of choice

Inhibitory effects of adhesion oligopeptides on the invasion of squamous carcinoma cells with special reference to implication of αv integrins

金沢大学大学院医学系研究科保健学専攻We studied invasion-related adhesion events in vitro using three squamous carcinoma cell lines (HSC-3, poorly differentiated type; OSC-19, well-differentiated type; and KB cells, undifferentiated type). An in vitro invasion assay through matrigel in the transwell chamber revealed that HSC-3 cells were most invasive, OSC-19 cells moderately invasive and KB cells least invasive. Inhibition assay of invasion using synthetic peptides RGD, RGDV, RGDS, RGDT, IKVAV and YIGSR, showed that invasion of the three cell lines was significantly inhibited by RGDV. There were other peptides that inhibited invasion significantly including IKVAV for HSC-3, and RGDS and YIGSR for OSC-19. HSC-3 cells and OSC-19 cells adhered to fibronectin, laminin, vitronectin, and type IV collagen, and KB cells did not adhere to laminin but did to fibronectin, vitronectin and collagen type IV. Pretreatment of cells with RGDV peptide in the attachment assay reduced the ability of these cells to bind to vitronectin and fibronectin more efficiently than pretreatment with RGDS. Anti-αv antibodies inhibited adhesion of HSC-3, OSC-19 and KB cells to vitronectin, but anti-β1 antibodies did not inhibit adhesion. Immunofluorescent microscopic examinations showed that all cell lines were positive for anti-β5 and anti-αv antibodies, and only HSC-β3 cells were positive for antiβ-3 antibody. α5β1 was not clearly demonstrated in any of the cell lines. RGDV was the most effective inhibitor of squamous cell carcinoma invasion among the synthetic oligopeptides used in this experiment, and it is suggested that it affects αvβ3-and/or αvβ5-mediated carcinoma cell invasion

Prognostic Impact of Pre- and Post-operative P-CRP Levels in Pancreatic Cancer Patients

Background: C-reactive protein (CRP) levels reflect ongoing inflammation and/or tissue damage, and studies suggest that platelets play a role in tumor invasion and metastasis. P-CRP is defined as the multiplied product of serum CRP and platelet levels. Here the prognostic value of pre- and post-operative P-CRP levels in pancreatic cancer (PC) patients was assessed. Methods: This retrospective study used data from 107 consecutive PC patients who had undergone either pancreaticoduodenectomy or distal pancreatectomy. Clinicopathological parameters and pre/post-operative laboratory data derived from patient records were used for analyses. P-CRP was defined as the product of peripheral thrombocyte count (/uL) × serum CRP level (mg/dL) divided by 104; the optimal P-CRP cut-off value was defined using receiver operating characteristic curves. Results: PC patients were classified as either P-CRPLow (< 1.782; n = 49) or P-CRPHigh (≥ 1.782; n = 58), based on the cut-off value of 1.782. Univariate analysis revealed that performance status, clinical stage, pathological T and N stages, P-CRP, and carbohydrate antigen 19-9 (CA19-9) significantly affected overall survival (OS). Multivariate analysis revealed that independent risk factors for OS were pathological N stage, P-CRP, and CA19-9. Additionally, 103 PC patients for whom postoperative data were available were classified into four groups (P-CRPLow-Down, P-CRPLow-Up, P-CRPHigh-Down and P-CRPHigh-Up), based on preoperative P-CRP and postoperative trend of P-CRP, and we found that prognosis, in terms of OS, was significantly different among these groups (P = 0.012). Conclusion: Pre- and post-operative P-CRP values are a potential predictor of prognosis in PC patients

Risk Score to Predict 1-Year Mortality after Haemodialysis Initiation in Patients with Stage 5 Chronic Kidney Disease under Predialysis Nephrology Care

Background Few risk scores are available for predicting mortality in chronic kidney disease (CKD) patients undergoing predialysis nephrology care. Here, we developed a risk score using predialysis nephrology practice data to predict 1-year mortality following the initiation of haemodialysis (HD) for CKD patients. Methods This was a multicenter cohort study involving CKD patients who started HD between April 2006 and March 2011 at 21 institutions with nephrology care services. Patients who had not received predialysis nephrology care at an estimated glomerular filtration rate (eGFR) of approximately 10 mL/min per 1.73 m2 were excluded. Twenty-nine candidate predictors were selected, and the final model for 1-year mortality was developed via multivariate logistic regression and was internally validated by a bootstrapping technique. Results A total of 688 patients were enrolled, and 62 (9.0%) patients died within one year of HD initiation. The following variables were retained in the final model: eGFR, serum albumin, calcium, Charlson Comorbidity Index excluding diabetes and renal disease (modified CCI), performance status (PS), and usage of erythropoiesis-stimulating agent (ESA). Their β-coefficients were transformed into integer scores: three points were assigned to modified CCI�3 and PS 3–4; two to calcium>8.5 mg/dL, modified CCI 1–2, and no use of ESA; and one to albumin7 mL/min per 1.73 m2, and PS 1–2. Predicted 1-year mortality risk was 2.5% (score 0–4), 5.5% (score 5–6), 15.2% (score 7–8), and 28.9% (score 9–12). The area under the receiver operating characteristic curve was 0.83 (95% confidence interval, 0.79–0.89). Conclusions We developed a simple 6-item risk score predicting 1-year mortality after the initiation of HD that might help nephrologists make a shared decision with patients and families regarding the initiation of HD.This work was supported by grants from the Institute for Health Outcomes & Process Evaluation research

Graphene for spintronics: giant Rashba splitting due to hybridization with Au

Graphene in spintronics has so far primarily meant spin current leads of high performance because the intrinsic spin-orbit coupling of its pi-electrons is very weak. If a large spin-orbit coupling could be created by a proximity effect, the material could also form active elements of a spintronic device such as the Das-Datta spin field-effect transistor, however, metal interfaces often compromise the band dispersion of massless Dirac fermions. Our measurements show that Au intercalation at the graphene-Ni interface creates a giant spin-orbit splitting (~100 meV) in the graphene Dirac cone up to the Fermi energy. Photoelectron spectroscopy reveals hybridization with Au-5d states as the source for the giant spin-orbit splitting. An ab initio model of the system shows a Rashba-split dispersion with the analytically predicted gapless band topology around the Dirac point of graphene and indicates that a sharp graphene-Au interface at equilibrium distance will account for only ~10 meV spin-orbit splitting. The ab initio calculations suggest an enhancement due to Au atoms that get closer to the graphene and do not violate the sublattice symmetry.Comment: 16 pages (3 figures) + supplementary information 16 pages (14 figures

Clinical Significance of Serum Antithrombin III Activity After Hepatectomy for Hepatocellular Carcinoma

[Background] As antithrombin III (AT-III) is produced in the hepatocytes, its serum activity decreases at the time of liver failure, in addition to ischemia reperfusion injury, vascular endothelial dysfunction, and disseminated intravascular coagulation (DIC). Here, we examined whether the serum AT-III value after hepatectomy could be a prognostic factor for hepatocellular carcinoma (HCC). [Methods] Of 141 patients who underwent hepatectomy for HCC, data for 101 patients in whom serum AT-III activity was measured on the first postoperative day were extracted. Patients with serum AT-III activity > 50% and ? 50% were assigned to high value (72 cases) and low value (29 cases) groups, respectively. We examined the clinical and prognostic differences between these two groups. [Results] The average age of enrolled patients (83 men and 18 women) was 68.0 years. The 5-year overall survival rate was 88% and 60% in the high and low value groups, respectively (P < 0.01). Furthermore, the 2-year relapse-free survival rate was 71% and 54% in the high and low value groups, respectively (P = 0.03). [Conclusion] This is the first study to demonstrate that serum AT-III levels on the first postoperative day may serve as a prognostic factor in HCC patients

The cometary composition of a protoplanetary disk as revealed by complex cyanides

Observations of comets and asteroids show that the Solar Nebula that spawned our planetary system was rich in water and organic molecules. Bombardment brought these organics to the young Earth's surface, seeding its early chemistry. Unlike asteroids, comets preserve a nearly pristine record of the Solar Nebula composition. The presence of cyanides in comets, including 0.01% of methyl cyanide (CH3CN) with respect to water, is of special interest because of the importance of C-N bonds for abiotic amino acid synthesis. Comet-like compositions of simple and complex volatiles are found in protostars, and can be readily explained by a combination of gas-phase chemistry to form e.g. HCN and an active ice-phase chemistry on grain surfaces that advances complexity[3]. Simple volatiles, including water and HCN, have been detected previously in Solar Nebula analogues - protoplanetary disks around young stars - indicating that they survive disk formation or are reformed in situ. It has been hitherto unclear whether the same holds for more complex organic molecules outside of the Solar Nebula, since recent observations show a dramatic change in the chemistry at the boundary between nascent envelopes and young disks due to accretion shocks[8]. Here we report the detection of CH3CN (and HCN and HC3N) in the protoplanetary disk around the young star MWC 480. We find abundance ratios of these N-bearing organics in the gas-phase similar to comets, which suggests an even higher relative abundance of complex cyanides in the disk ice. This implies that complex organics accompany simpler volatiles in protoplanetary disks, and that the rich organic chemistry of the Solar Nebula was not unique.Comment: Definitive version of the manuscript is published in Nature, 520, 7546, 198, 2015. This is the author's versio

Functional and neurometabolic asymmetry in SHR and WKY rats following vasoactive treatments

A lateralized distribution of neuropeptidase activities in the frontal cortex of normotensive and hypertensive rats has been described depending on the use of some vasoactive drugs and linked to certain mood disorders. Asymmetrical neuroperipheral connections involving neuropeptidases from the left or right hemisphere and aminopeptidases from the heart or plasma have been suggested to play a role in this asymmetry. We hypothesize that such asymmetries could be extended to the connection between the brain and physiologic parameters and metabolic factors from plasma and urine. To assess this hypothesis, we analyzed the possible correlation between neuropeptidases from the left and right frontal cortex with peripheral parameters in normotensive (Wistar Kyoto [WKY]) rats and hypertensive rats (spontaneously hypertensive rats [SHR]) untreated or treated with vasoactive drugs such as captopril, propranolol and L-nitro-arginine methyl ester. Neuropeptidase activities from the frontal cortex were analyzed fluorometrically using arylamide derivatives as substrates. Physiological parameters and metabolic factors from plasma and urine were determined using routine laboratory techniques. Vasoactive drug treatments differentially modified the asymmetrical neuroperipheral pattern by changing the predominance of the correlations between peripheral parameters and central neuropeptidase activities of the left and right frontal cortex. The response pattern also differed between SHR and WKY rats. These results support an asymmetric integrative function of the organism and suggest the possibility of a different neurometabolic response coupled to particular mood disorders, depending on the selected vasoactive drug.This work was supported by the Ministry of Science and Innovation through project no. SAF 2008 04685 C02 01