Detecting Chlamydia trachomatis in men with urethritis: serology v isolation in cell culture.

The accuracy of single serovar (L2) inclusion immunoperoxidase assay (IPA) to show serum IgG and IgA antibodies specific to chlamydiae was compared with culture for Chlamydia trachomatis to diagnose chlamydial infection in 73 men with acute urethritis. C trachomatis only was isolated from 18 (25%), Neisseria gonorrhoeae only from 17 (23%), and both organisms from six (8%). Thus 24 (33%) yielded chlamydiae. Assays based on IgG antibodies to chlamydiae at a titre of 1/64 or more showed high sensitivity (96%) and a good negative predictive value (80%), but low specificity (13%) and agreement (48%) compared with culture. IgG antibodies to chlamydiae at a titre of 1/128 or more showed lower sensitivity (75%) but higher specificity (72%), negative predictive value (79%), and agreement (73%). IgA antibodies to chlamydiae at a titre of 1/8 or more showed a sensitivity of 88%, specificity of 72%, negative predictive value of 88%, and agreement of 79%. An appreciable (fourfold or more) decrease in IgA and IgG titres was observed in most (10) of the 15 men from whom second blood samples were obtained one to two years after treatment. Measuring specific IgA and IgG antibodies to chlamydiae by IPA may serve as a useful complementary test for diagnosing and following up patients with urethritis.     

Ovarian cancer patients at high risk of <Emphasis Type="Italic">BRCA</Emphasis> mutation: the constitutional genetic characterization does not change prognosis

Ovarian neoplasms secondary to germline BRCA mutations had been described to have a more favourable survival. There is only few data concerning the prognosis of non mutated patients presenting clinical features evocative of BRCA alterations. We retrospectively collected data from patients treated in our institution for an invasive ovarian carcinoma between 1995 and 2011. Patients considered at high risk of BRCA mutation were tested for BRCA1/2 germline mutations. We described clinical, pathological and therapeutic features and compared prognosis of BRCA mutation carriers and non-mutated patients. Out of 617 ovarian cancer patients, we identified 104 patients who were considered at high risk of mutation. The 33 mutated patients were more likely to present a personal (33 vs. 10 %, p = 0.003) or a family (42 vs. 24 %, p = 0.06) history of breast/ovarian cancers. BRCA1/2 mutation carriers and wild type patients displayed similar prognosis: median progression–free survival (PFS) of 20.9 versus 37.7 months (p = 0.21); median overall survival (OS) of 151.2 versus 122.5 months (p = 0.52). Personal history of breast cancer increased both PFS [HR = 0.45 (95CI 0.25–0.81)] and OS [HR = 0.35 (95CI 0.16–0.75)]. In multivariate analysis, this parameter was an independent prognostic feature, whereas the identification of a BRCA1/2 mutation was not. In our cohort, all patients at high risk of BRCA mutation share a similar prognosis, whatever is their germline mutation status. Prognosis seems to be more influenced by clinical history than by germline mutations identification. If it is confirmed in larger and independent series, this result suggests that the hypothesis of other BRCA pathway alterations (BRCAness phenotype) deserves to be deeply explored.     

Statistical assessment of the stability of neural movement representations

In systems neuroscience, neural activity that represents movements or sensory stimuli is often characterized by spatial tuning curves that may change in response to training, attention, altered mechanics, or the passage of time. A vital step in determining whether tuning curves change is accounting for estimation uncertainty due to measurement noise. In this study, we address the issue of tuning curve stability using methods that take uncertainty directly into account. We analyze data recorded from neurons in primary motor cortex using chronically implanted, multielectrode arrays in four monkeys performing center-out reaching. With the use of simulations, we demonstrate that under typical experimental conditions, the effect of neuronal noise on estimated preferred direction can be quite large and is affected by both the amount of data and the modulation depth of the neurons. In experimental data, we find that after taking uncertainty into account using bootstrapping techniques, the majority of neurons appears to be very stable on a timescale of minutes to hours. Lastly, we introduce adaptive filtering methods to explicitly model dynamic tuning curves. In contrast to several previous findings suggesting that tuning curves may be in constant flux, we conclude that the neural representation of limb movement is, on average, quite stable and that impressions to the contrary may be largely the result of measurement noise.     

Teaching rotary root canal instrumentation using a Peyton teaching approach

Introduction

The aim of the study was two evaluate the effectiveness of a Peyton teaching approach for rotary root canal instrumentation, in comparison to the traditional “see one–do one” method.

Material and Methods

Forty undergraduate students were randomly divided into two groups (n = 20). Students of the first group (G1) were taught how to use rotary instrumentation using a modified Peyton method, whilst the second group (G2) watched a teaching video (30 min) on the same subject. Both groups instrumented a plastic block and subsequently both mesial canals of an extracted lower molar. The quality of the root canal instrumentation was analysed by 2 blinded observers on video recordings and x-rays.

Results

Interobserver correlation was 0.917 (p < .0005; Pearson) for the assessment of the video recordings; students of G1 received significantly more total points (83.55 ± 6.82 points) compared to G2 (69.76 ± 13.82) (p = .001; t-test), the gender had no significant effect on the overall results (p = .444; two-way ANOVA). Significant differences were detected for the categories “initial scouting,” “coronal enlargement,” “glide path preparation,” “preparation using X2 file,” “preparation using X3 file” (p < .05; t-test) as well as for the subcategories “sequence of rinse, recapitulation, rinse” (p = .001; t-test) and “recapitulation” (p < .002; t-test). No differences between groups were observed for the radiographic evaluation with respect to working length and canal straightening.

Conclusion

Teaching rotary instrumentation by using the Peyton approach resulted in improved performance of undergraduate students assessed with a checklist-based process analysis. Enhanced implementation of rotary instrumentation could result in better long-term results of students' root canal treatment.     

Systemic antibiotics in endodontics—International questionnaire study: Choice of types,dosage, loading and duration

The aim of the study was to investigate the systematic antibiotics (SAs) prescribing practices in the endodontic practice worldwide. 7500 general practitioners, postgraduate students and endodontists from Israel and the former Soviet Union (FSU) states were invited to fill in an online questionnaire. The first-choice SA was amoxicillin (80.12%) among the Israeli (p < 0.05) and amoxicillin + clavulanic acid (88.92%) among the FSU respondents (p < 0.05). The first-choice SA for patients with penicillin allergy was clindamycin (78.2%) among Israeli and azithromycin (35.96%) among the FSU respondents (p < 0.05). Most of the respondents from Israel as well as from the FSU reported prescribing SA for 5–7 days. Only 6.24% of the former and 2.59% of the latter reported prescribing SA until the symptoms disappeared (p > 0.05). The usage of SAs is often not in accordance with existing international guidelines and differs among different dentist's populations.