Treatment outcomes after uncomplicated and complicated crown fractures in permanent teeth

Clinical Oral Investigations - The objectives of this retrospective clinical study were to describe characteristics of crown fractures in permanent teeth and to investigate the survival of pulp...     

Anatomical basis for the intrahepatic glissonian approach during hepatectomies

Background

Anatomical liver resections are based on some basic technical principles such as vascular control, ischemic area delineation to be resected and maximum parenchymal preservation. These aspects are achieved by the intrahepatic glissonian approach, which consists in accessing the pedicles of hepatic segments within the hepatic parenchyma. Small incisions on well-defined anatomical landmarks are performed to approach the pedicles, making dissection of the hilar plate unnecessary.

Aim

Analyze parameters in liver anatomy related to intrahepatic surgical technique to glissonians pedicles, to set the normal anatomy related to the procedure and thereby facilitate the attainment of this technique.

Methods

Anatomical parameters related to the intrahepatic glissonian approach were studied in 37 cadavers. Measurements were performed with precision instruments. Data were expressed as mean±standard deviation. The subjects were divided into groups according to gender and liver weight and groups were compared statistically.

Results

Twenty-five cadavers were male and 12 female. No statistically significant difference was observed in virtually all parameters when groups were compared. This demonstrates the consistency of the anatomical parameters related to the intrahepatic glissonian approach.

Conclusion

The results obtained in this study made possible major technical advances in the realization of open and laparoscopic hepatectomies with intrahepatic glissonian approach, and can help surgeons to perform liver resections by this method.     

Concept of variable angle locking—evolution and mechanical evaluation of a recent technology

Applications for fracture‐adapted screw positioning offered by variable angle locking screws are increasing. The locking strength of the variable angle locking mechanism at different insertion angles was compared to conventional fixed angle locking screws. Stainless steel (S) and titanium (Ti) variable and fixed angle 2.4 mm locking screws, inserted at different inclinations (0°?15°), and locked at 0.8 Nm were subjected to a load‐to‐failure test. Ultimate failure moment at the screw‐head interface and failure mode of the screws were determined. Significant differences were detected by one‐way ANOVA (p < 0.05). Stainless steel and titanium variable angle locking screws inserted at 2°?10° inclination exhibited a failure moment comparable to the 0° position (S 1.67± 0.04 Nm; Ti 1.67 ± 0.14 Nm) and failed predominantly at the screw neck, with the head remaining fixed to the plate. Inserted at 15° inclination, screws revealed a lower failure moment (S 1.33 ± 0.06 Nm, Ti 1.58 ± 0.05Nm), and failed predominantly by breakout of the head thread. Fixed angle locking screws inserted at an inclination >2° did not lock properly in the plate hole, providing insufficient locking strength. Variable angle locking screws offer a stable head‐locking mechanism at different inclinations, comparable to the locking strength of orthogonal inserted fixed angle locking screws. Marginal inclinations >15° should be used with care. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:988–992, 2015.

     

Insight into the PrPC-->PrPSc conversion from the structures of antibody-bound ovine prion scrapie-susceptibility variants

Prion diseases are associated with the conversion of the alpha-helix rich prion protein (PrPC) into a beta-structure-rich insoluble conformer (PrPSc) that is thought to be infectious. The mechanism for the PrPC-->PrPSc conversion and its relationship with the pathological effects of prion diseases are poorly understood, partly because of our limited knowledge of the structure of PrPSc. In particular, the way in which mutations in the PRNP gene yield variants that confer different susceptibilities to disease needs to be clarified. We report here the 2.5-A-resolution crystal structures of three scrapie-susceptibility ovine PrP variants complexed with an antibody that binds to PrPC and to PrPSc; they identify two important features of the PrPC-->PrPSc conversion. First, the epitope of the antibody mainly consists of the last two turns of ovine PrP second alpha-helix. We show that this is a structural invariant in the PrPC-->PrPSc conversion; taken together with biochemical data, this leads to a model of the conformational change in which the two PrPC C-terminal alpha-helices are conserved in PrPSc, whereas secondary structure changes are located in the N-terminal alpha-helix. Second, comparison of the structures of scrapie-sensitivity variants defines local changes in distant parts of the protein that account for the observed differences of PrPC stability, resistant variants being destabilized compared with sensitive ones. Additive contributions of these sensitivity-modulating mutations to resistance suggest a possible causal relationship between scrapie resistance and lowered stability of the PrP protein.     

Alterations in Brain Polyribosomal RNA Translation and Lymphocyte Proliferation in Prenatal Ethanol-Exposed Rats

The long-term effects of prenatal ethanol exposure on the properties of brain polysomes and the proliferative responses of lymphocytes to mitogenic stimulation in adult offspring were assessed. Female Sprague-Dawley rats either ingested the control or 6.6% ethanol-containing Lieber-DeCarli liquid diet during the 3rd trimester of pregnancy. Controls were age-matched and pair-fed. At 42 to 72 days of age, ethanol effects were evaluated on the (1) polysomal properties in the cerebral hemispheres, cerebellum, and hippocampal regions of the brain after translation in a messenger RNA (mRNA)-dependent rabbit reticulocyte lysate system and (2) immunologic functions of lymphocytes cultured from spleen cells by measuring their responses to mitogenic stimulation. Results showed long-term adverse effects of in utero ethanol exposure on the polysomal RNA translation in each of the three brain regions tested with free polysomal mRNAs affected more than the bound polysomal mRNAs. Of these, the hippocampal region appeared to sustain the most injurious effects. In addition, a suppression of the mitogen-induced lymphocyte proliferative responses were present under these conditions. The degree of suppression varied with the specific mitogen used. Data suggest that the ethanol effects on the CNS and lymphocyte proliferation are most possibly irreversible, and in the case of the CNS, a post-translational modification by ethanol is indicated. The reduced lymphocyte responses are suggestive of a possible interference by ethanol of the synthesis of interleukin-2 (IL-2) and/or a reduced binding of IL-2 with its receptor (IL-2 receptors).     

Combining brentuximab vedotin with dexamethasone,high-dose cytarabine and cisplatin as salvage treatment in relapsed or refractory Hodgkin lymphoma: the phase II HOVON/LLPC Transplant BRaVE study

Achieving a metabolic complete response (mCR) before high-dose chemotherapy (HDC) and autologous peripheral blood stem cell transplant (auto-PBSCT) predicts progression-free survival (PFS) in relapsed/refractory classical Hodgkin lymphoma (R/R cHL). We added brentuximab vedotin (BV) to DHAP (dexamethasone, high-dose cytarabine, cisplatin) to improve the mCR rate. In a phase I dose-escalation part of the study in 12 patients, we showed that BV-DHAP is feasible. This phase II study included 55 R/R cHL patients (23 primary refractory). Treatment consisted of three 21-day cycles of BV 1.8 mg/kg on day 1, and DHAP (dexamethasone 40 mg days 1-4, cisplatin 100 mg/m² day 1 and cytarabine 2x2 g/m² day 2). Patients with a metabolic partial response (mPR) or mCR proceeded to HDC/auto-PBSCT. Based on independent central [¹⁸F]fluorodeoxyglucose (FDG) - positron emission tomography (PET) - computed tomography (CT) scan review, 42 of 52 evaluable patients (81% [95%CI: 67-90]) achieved an mCR before HDC/auto-PBSCT, five had an mPR and five had progressive disease (3 were not evaluable). After HDC/auto-PBSCT, four patients with an mPR converted to an mCR. Two-year PFS was 74% [95%CI: 63-86] and overall survival 95% [95%CI: 90-100]. Toxicity was manageable and mainly consisted of grade 3/4 hematologic toxicity, fever, nephrotoxicity, ototoxicity (grade 1/2), and transiently elevated liver enzymes during BV-DHAP. Eighteen patients developed new onset peripheral neuropathy (maximum grade 1/2); all recovered. In conclusion, BV-DHAP is a very effective salvage regimen in R/R cHL patients, but patients should be monitored closely for toxicity. (clinicaltrials.gov identifier: {"type":"clinical-trial","attrs":{"text":"NCT02280993","term_id":"NCT02280993"}}NCT02280993).     

Surveillance and response: Tools and approaches for the elimination stage of neglected tropical diseases

The presentation of the World Health Organization (WHO)’s roadmap for neglected tropical diseases (NTDs) in January 2012 raised optimism that many NTDs can indeed be eliminated. To make this happen, the endemic, often low-income countries with still heavy NTD burdens must substantially strengthen their health systems. In particular, they need not only to apply validated, highly sensitive diagnostic tools and sustainable effective control approaches for treatment and transmission control, but also to participate in the development and use of surveillance–response schemes to ensure that progress made also is consolidated and sustained. Surveillance followed-up by public health actions consisting of response packages tailored to interruption of transmission in different settings will help to effectively achieve the disease control/elimination goals by 2020, as anticipated by the WHO roadmap. Risk-mapping geared at detection of transmission hotspots by means of geospatial and other dynamic approaches facilitates decision-making at the technical as well as the political level. Surveillance should thus be conceived and developed as an intervention approach and at the same time function as an early warning system for the potential re-emergence of endemic infections as well as for new, rapidly spread epidemics and pandemics.