Natural history of intraventricular meningiomas: systematic review

Review the data published on the subject to create a more comprehensive natural history of intraventricular meningiomas (IVMs). A Medline search up to March 2018 using “intraventricular meningioma” returned 98 papers. As a first selection step, we adopted the following inclusion criteria: series and case reports about IVMs, as well as papers written in other languages, but abstracts written in English were evaluated. Six hundred eighty-one tumors were evaluated from 98 papers. The majority of the tumors were located in the lateral ventricles (602–88.4%), fourth ventricle (59–8.7%), and third ventricle (20–2.9%). These tumors accounted for a mortality rate of 4.0% (25 deaths) and a recurrence rate of 5.3% (26 recurrences). The majority of the tumors were grade I (89.8%) and consisted of the following subtypes: fibrous, 39.7% (n = 171); transitional, 22.0% (n = 95); meningothelial, 18.6% (n = 80); angiomatosus, 3.2% (n = 14); psammomatous, 2.6% (n = 11); and others, 13.9% (n = 60). Forty-five patients (7.4%) presented with grade II (GII) tumors, and 17 patients (2.8%) presented with grade III (GIII) tumors. These tumors follow the histopathological distribution of meningiomas in general, with the exception of the higher prevalence of the fibrous subtype, possibly due to its embryonic origin. Recurrence and mortality were lower than in other localizations likely due to a complete surgical resection rate than in the convexity and skull base, which suggests that GTR is the gold standard for the management of IVMs.     

Interatrial block can occur in the absence of left atrial enlargement: New experimental model

We present the surface electrocardiogram of an open-chest anesthetized healthy adult swine after direct application of ice at the transversus sinus of the pericardium where the Bachmann's region is located. Gradual and transient interatrial block (IAB) in the absence of structural atrial disease is described. This new experimental model demonstrated that IAB is an independent entity from left atrial enlargement.     

KIR and a specific HLA-C gene are associated with susceptibility and resistance to hepatitis B virus infection in a Brazilian population

BRIEF REPORT The activity of natural killer （NK） cells is partially regulated by killer cell immunoglobulin-like receptors （KIRs） interacting with human leukocyte antigen C （HLA-C） ligands.1 The ligands of several inhibitory （2DL and 3DL） and activating （2DS and 3DS） KIR have been described.     

The Radix Entomolaris and Paramolaris: A Micro–Computed Tomographic Study of 3-rooted Mandibular First Molars

Introduction

The morphology of the supernumerary third root (radix) in mandibular first molars was examined by micro–computed tomography (μCT) scanning.

Methods

Nineteen permanent mandibular first molars with radix were scanned in a μCT device to evaluate their morphology with respect to root length, root curvature direction, location of radix, apical foramen, accessory canals and apical deltas, and distance between canal orifices as well as 2- and 3-dimensional parameters of the canals (number, area, roundness, major/minor diameter, volume, surface area, and structure model index). Quantitative data were analyzed by 1-way analysis of variance and the Tukey test (α = 0.05).

Results

The mean length of the mesial, distal, and radix roots was 20.36 ± 1.73 mm, 20.0 ± 1.83 mm, and 18.09 ± 1.68 mm, respectively. The radix was located distolingually (n = 16), mesiolingually (n = 1), and distobuccally (n = 2). In a proximal view, most radix roots had a severe curvature with buccal orientation and a buccally displaced apical foramen. The spatial configuration of the canal orifices on the pulp chamber floor was mostly in a trapezoidal shape. The radix root canal orifice was usually covered by a dentinal projection. The radix differed significantly from the mesial and distal roots for all evaluated 3-dimensional parameters (P < .05). The radix canal had a more circular shape in the apical third, and the mean size of the minor diameter 1 mm short of the foramen was 0.25 ± 0.10 mm.

Conclusions

The radix root is an important and challenging anatomic variation of mandibular first molars, which usually has a severe curvature with a predominantly distolingual location, and a narrow root canal with difficult access.     

INFLUENCE OF PROTAPER FINISHING FILES AND SODIUM HYPOCHLORITE ON CLEANING AND SHAPING OF MANDIBULAR CENTRAL INCISORS – A HISTOLOGICAL ANALYSIS

Objective:

This study investigated the influence of the last apical instrument of the ProTaper system with and without 2.5% sodium hypochlorite for cleaning mandibular central incisors.

Material and Methods:

Thirty two mandibular central incisors were divided into six study groups: Group I – F1 instrument with 2.5% sodium hypochlorite; Group II – F1 and F2 with 2.5% sodium hypochlorite; Group III – F1, F2 and F3 with 2.5% sodium hypochlorite; Group IV – F1 with distilled water; Group V – F1 and F2 with distilled water; Group VI – F1, F2 and F3 with distilled water. The two remaining teeth comprised the negative control group. The specimens were prepared following the principles of the technique suggested by the manufacturer and then submitted to histological preparation and morphometric analysis. Data were analyzed statistically by the Kruskal Wallis test at 1% significance level.

Results:

There was statistically significant difference (p<0.01) between all study groups, except between Groups I and VI.

Conclusions:

It was concluded that no technique allowed complete cleaning of the root canals. However, the technique of finishing preparation of the apical third with the F3 instrument with 2.5% sodium hypochlorite irrigation was the most effective.     

Heparan sulfate fine-tunes stromal-epithelial communication in the prostate gland

Several studies reported the concerted and mutual communication between the prostate epithelium and stroma, which determines the final organ architecture and function, but gets awry in cancer. Deciphering the mechanisms involved in this communication is crucial to find new therapeutic strategies. HS sequesters a number of secreted growth factors and cytokines, controlling their bioavailability to the target cells, suggesting that HS is an important regulator of the extracellular matrix (ECM) and a key player in the cell-cell and cell-microenvironment communication during prostate morphogenesis and physiology. We propose that by controlling HS biosynthesis and sulfation pattern, as well as the cleavage of the HS chain and/or the shedding of proteoglycans, epithelial and stromal cells are able to precisely tune the availability of signaling molecules and modulate ligand-receptor interaction and intracellular signal transduction.     

Average spectral power changes at the hippocampal electroencephalogram in schizophrenia model induced by ketamine

The use of ketamine (Ket) as a pharmacological model of schizophrenia is an important tool for understanding the main mechanisms of glutamatergic regulated neural oscillations. Thus, the aim of the current study was to evaluate Ket‐induced changes in the average spectral power using the hippocampal quantitative electroencephalography (QEEG). To this end, male Wistar rats were submitted to a stereotactic surgery for the implantation of an electrode in the right hippocampus. After three days, the animals were divided into four groups that were treated for 10 consecutive days with Ket (10, 50, or 100 mg/kg). Brainwaves were captured on the 1st or 10th day, respectively, to acute or repeated treatments. The administration of Ket (10, 50, or 100 mg/kg), compared with controls, induced changes in the hippocampal average spectral power of delta, theta, alpha, gamma low or high waves, after acute or repeated treatments. Therefore, based on the alterations in the average spectral power of hippocampal waves induced by Ket, our findings might provide a basis for the use of hippocampal QEEG in animal models of schizophrenia.