Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Study the Prevalence of Cysticercus Tenuicollis in Sheep and Goats in Baghdad City

Cysticercus tenuicollis larval stage of dog's parasite Taenia hydatigena located in visceral organs of intermediate hosts (sheep and goats). In this study, the total of 100 sheep and 100 goats' visceral organs were inspected, C. tenuicollis was found in sheep was 21% (21/100); while the rate of infection was 35% in goats (35/100).  According to the months of the study, the high rate in sheep was revealed in July, June, and August, 40% (4/10), 30% (3/10), and 25% (5/25) respectively; while the lowest rate was 10% (1/10) was recorded in January, March, April while in goats the lowest rate in March, February, and April was 20% (2/10), 30% (3/10), 30% (3/10) respectively, the rest of the months was 40% (4/10). In sheep, the highest infection rate with C. tenuicollis was 21.42% (18/84) in sheep males while the lowest rate was 18.75% (3/16) in sheep females while in goats the highest infection rate with C. tenuicollis was 35% (35/100) in males and lowest in female 0% (0).&nbsp

Cyclic fatigue analysis of twisted file rotary NiTi instruments used in reciprocating motion

Gambarini G, Gergi R, Naaman A, Osta N, Al Sudani D. Cyclic fatigue analysis of twisted file rotary NiTi instruments used in reciprocating motion. International Endodontic Journal, 45, 802806, 2012. Abstract Aim To evaluate the cyclic fatigue fracture resistance of engine-driven twisted file (TF) instruments under reciprocating movement. Methodology A sample of 30 size 25, 0.08 taper NiTi TF instruments was tested in a simulated canal with 60 degrees angle of curvature and a 3 mm radius. During mechanical testing, different movement kinematics were used at a constant speed, which resulted in three experimental groups (each group n = 10). The instruments from the first group (G1) were rotated until fracture occurred. The instruments in the second (G2) and third group (G3) were driven under reciprocating movement with different angles of reciprocation. The time of fracture for each instrument was measured, and statistical analysis was performed using one-way analysis of variance followed by Tukeys Honestly Significant Different test. Results Reciprocating movement resulted in a significantly longer cyclic fatigue life (P < 0.0001) when compared with continuous rotation. No difference was found between reciprocation 150 degrees clockwise/30 degrees counterclockwise (CW/CCW) and 30 degrees CW/150 degrees CCW. Conclusions The reciprocating movement was associated with an extended cyclic fatigue life of the TF size 0.25, 0.08 taper instruments in comparison with conventional rotation

Incidence and intensivity of postoperative pain and periapical inflammation after endodontic treatment with two different instrumentation techniques

Apical extrusion of infected debris to the periradicular tissues is considered one of the possible factors related to the occurrence of postoperative pain and inflammation. The goal of the present study is to evaluate and compare the incidence and intensity of postoperative pain using two different nickel-titanium instrumentation techniques: a rotary crown-down technique using TF instruments ( SybronEndo, Orange, Ca, USA) and a reciprocating single-file technique using Reciproc instruments (VDW, Munich, Germany). Sixty patients requiring endodontic treatment on permanent premolar and molar teeth with non-vital pulps preoperatively were included in the study. The patients were divided into two groups of 30 patients each, trying to make the groups very similar, concerning the number of root canals, presence of initial pain and periapical lesions. The teeth in group 1 (n = 30) were treated with a crown-down technique using TF instruments whilst those in group 2 (n = 30) were treated with a single-file technique using Reciproc 08 25. All canals were shaped, cleaned and obturated in a single-visit. The assessment of postoperative pain was carried out at 3 days by using a visual analogue scale. Chi-square tests and independent-sample t-tests to compare the incidence and intensity of postoperative pain of two groups were carried out. A statistically significant difference was found between the two techniques. When comparing patients who developed no pain, the TF instrumentation technique showed significantly better results (chi-square = 4.059 P = 0.039). When evaluating patients experiencing severe pain the incidence of symptoms was significantly higher with the Reciproc technique (chi-square = 7.246 P = 0.023). Since the incidence of preoperative pain, the type of tooth and the pulp and periodontal pathology were quite similar between the two tested groups, and all the other variables (operator, irrigation, and obturation) were identical, the difference in postoperative pain can be mainly related to the different instrumentation technique. Copyright © by BIOLIFE, s.a.s

Mechanical properties of nickel-titanium rotary instruments produced with a new manufacturing technique

P>Aim To investigate whether flexibility and cyclic fatigue resistance was increased for nickel-titanium instruments produced by a new manufacturing technique. Methodology Forty K3 tip size 25, 0.06 taper (SybronEndo) nickel-titanium rotary instruments were randomly selected and divided into two groups (n = 20). One group served as control, being the commercially available instruments produced with a traditional grinding process (K3). The second group of instruments (K4 prototypes) were then subjected to a proprietary thermal treatment after the grinding process. Finally, each group was randomly divided into two subgroups of 10 instruments each, to perform the stiffness test and the cyclic fatigue test. All data were recorded and subjected to statistical evaluation using Student's t-test. Significance was set at the 95% confidence level. Results For the stiffness test, a statistically significant difference (P < 0.05) was noted between K3 and K4 prototype instruments. K4 prototype instruments were significantly more flexible when compared to K3 instruments (59.3 +/- 4.3 vs. 98.1 +/- 6.4 g cm-1). For the cyclic fatigue test, a significant difference (P < 0.05) was noted between K3 and K4 prototype instruments. K4 prototype instruments demonstrated a significant increase in the mean number of cycles to failure (NCF) when compared to K3 instruments (1198 +/- 279 vs. 542 +/- 81 NCF). Conclusions The new manufacturing technique resulted in the K4 prototype instruments having enhanced mechanical properties, compared to K3 instruments, manufactured with a traditional grinding process

Cyclic fatigue resistance of Mtwo NiTi rotary instruments used by experienced and novice operators - an in vivo and in vitro study

Background: The aim of the present study was to evaluate the cyclic fatigue resistance of Mtwo NiTi rotary instruments after clinical use by 1 experienced and 1 novice operator. Material/Methods: Cyclic fatigue testing of instruments was performed on tapered artificial canals with a 5 mm radius of curvature and 60° angle of curvature. Twenty Mtwo instruments for each size were selected and divided into 2 groups: group A consisted of 10 instruments of each size used for shaping 10 root canals in molar teeth of patients by an experienced operator; group B consisted of 10 instruments of each size used for shaping 10 root canals in molar teeth of patients by a novice operator. Instruments were rotated until fracture occurred and the numbers of cycles to failure (NCF) were recorded. Data obtained were subjected to an independent sample t-test to determine statistical differences. The significance was determined at a 95% confidence level. Results: No statistically significant difference (P&lt;0.05) was noted between the instruments of groups A and B for all sizes. More instruments with visible signs of plastic deformation were identified for the novice operator. Conclusions: The clinical use of Mtwo NiTi rotary instruments by a novice operator did not significantly affect the cyclic fatigue resistance when compared with the control group of the same instrument sizes used by an experienced operator. It can be concluded that novice operators can use these instruments safely under the recommended technical guidelines. © Med Sci Monit

Influence of file motion on cyclic fatigue of new nickel titanium instruments.

The aim of the present study was to compare the resistance to cyclic fatigue of Hyflex® (Coltene-Whaledent, Allstatten, Switzerland) size 40 taper.04 nickel titanium instruments used in continuous rotation versus the use with a reciprocating motion. The null hypothesis was that different file motions had no influence on the lifetime of instruments subjected to a cyclic fatigue test. 24 Hyflex® size 40 taper.04 nickel titanium instruments were randomly divided in two groups (n=12 each), and submitted to a cyclic fatigue test. The first group (CR group) were used with a continuous rotation, while the second one (RCP group) with a reciprocating motion. The cyclic fatigue tests were performed by using a stainless steel block containing an artificial canal shaped with a 135° angle. All instruments were rotated or reciprocated until fracture occurred. The time to fracture was recorded visually with a 1/100 second chronometer. Data were recorded and statistically analysed. Results indicated that instruments used with a reciprocating motion showed a significant increase in the meantime to failure when compared to those used in continuous rotation. The null hypothesis was rejected. Results of the present study showed that reciprocating motion extended resistance to cyclic fatigue of the tested nickel titanium instruments, when compared to continuous rotation

The influence of three different instrumentation techniques on the incidence of postoperative pain after endodontic treatment.

Apical extrusion of infected debris to the periradicular tissues is one of the principal causes of postoperative pain and discomfort. Recent researches have shown that reciprocating instrumentation techniques seem to significantly increase the amount of debris extruded beyond the apex and, consequently, the risk of postoperative pain. The goal of the present study was to evaluate and compare postoperative pain using three different nickel-titanium instrumentation techniques: a rotary crown-down technique using TF instruments (SybronEndo, Orange, Ca), a reciprocating single-file technique using WaveOne instruments (Maillefer DEntsply, Baillagues, CH), and a novel instrumentation technique (TF Adaptive, SybronEndo, Orange, Ca), using a unique, proprietary movement, combining reciprocation and continuous rotation. Ninety patients requiring endodontic treatment on permanent premolar and molar teeth with non vital pulps preoperatively were included in the study. The patients were assigned into three groups of 30 patients each, trying to make the groups very similar, concerning the number of root canals, presence of initial pain and periapical lesions. The teeth in group 1 (n = 30) were instrumented with a crown-down technique using TF instruments, whilst those in group 2 (n = 30) were instrumented with a single-file technique using Waveone 08 25. The third group (n = 30) used the 3-file Tf Adaprtive sequence. All techniques were performed following manufacturers' instructions and all canals were shaped, cleaned and obturated in a single-visit by the same operator. The assessment of postoperative pain was carried out at 3 days by using a visual analogue scale. VAS pain scores were compared using one-way ANOVA post hoc Tukey test. A value of p < 0.05 was required for statistical significance. Results for VAS pain scores showed a statistically significant difference was found between the WaveOne (p=0,021) technique and the other two techniques. No statistical significant differences were found between TF and TF Adaptive (p= 0,087). When evaluating patient experiencing sever pain the incidence of symptoms was significantly higher with the WaveOne technique. Since the incidence of preoperative pain, the type of tooth and the pulp and periodontal pathology were quite similar between the three tested groups, and all the other variables (operator, irrigation, obturation) were identical, we may conclude that the difference in postoperative pain can be mainly related to the different instrumentation techniques