Diagnostic assessment of patients with Meniere's disease through caloric testing and the video-head-impulse test

IntroductionMeniere's disease is a labyrinth disease that usually presents with episodes of spontaneous vertigo associated with sensorineural hearing loss, tinnitus and ipsi- and unilateral aural fullness in most cases. Vestibular function tests, video-head-impulse test and the caloric test, are not specific for diagnosis of the disease, but may show alterations that help to evaluate the functional impairment.ObjectiveTo describe the results obtained at the caloric test and video-head-impulse test in patients with definite Meniere's disease and compare them between symptomatic, asymptomatic ears and those of the control group.MethodsCross-sectional and observational study including patients with definite Meniere's disease diagnosed according to the Bárány Society criteria (2015) and healthy individuals (control group) undergoing caloric test and video-head-impulse test. All subjects were assessed by neurotological anamnesis and audiological evaluation (pure-tone, vocal and immittance audiometry) to characterize the sample. The findings obtained at the caloric test and video-head-impulse test were described and compared between the symptomatic and asymptomatic ears of patients with Meniere's disease and those of the control group.ResultsThirty-two patients with definite Meniere's disease were evaluated, with a mean age of 45.7 years, mostly females (68.8%) and unilateral disease. The control group consisted of 20 healthy individuals, with a mean age of 44.7 years, mostly females (70.0%). The groups were homogeneous in relation to age and gender. The patients’ main complaint was vertigo (71.9%), and most patients had more than six episodes in the last six months (71.9%). Moderate sensorineural hearing loss was present in 38.5% of patients. The prevalence of hyporeflexia at the caloric test was higher in symptomatic (56.4%) and asymptomatic (36%) ears of patients with Meniere's disease compared to the ears of control subjects (7.5%), p < 0.001 and p = 0.004, respectively. Video-head-impulse test alterations in the lateral semicircular canals were more frequent in the symptomatic ears of patients with Meniere's disease than in the ears of control subjects (p = 0.026).ConclusionMost patients with definite Meniere's disease showed hyporeflexia at the caloric test and video-head-impulse test with normal function in the symptomatic ear. Vestibular hyporeflexia at the caloric test was more frequent in the symptomatic and asymptomatic ears of patients with Meniere's disease than in the control group. The video-head-impulse test showed more alterations in the lateral semicircular canals.     

Tuning the Biginelli reaction mechanism by the ionic liquid effect: the combined role of supported heteropolyacid derivatives and acidic strength

Herein, a combination of heteropolyacids and ionic liquids as a catalytic system was studied for the Biginelli multicomponent reaction; the positive ionic liquid effect associated with the acidic strength of zeolite-supported heteropolyacids made this combination an efficient catalytic system for the multicomponent synthesis of 3,4-dihydropyrimidin-2(1H)-one/thione derivatives. The acidic strength effect was evaluated, and a range was determined in which the reaction provided better results. The mechanism of the reaction was also investigated in the presence and absence of ionic liquids, and two features of paramount importance were revealed: the mechanism could be tuned to proceed through only one reaction path among three possibilities and the kinetics of the reaction was significantly faster in the presence of an ionic liquid.

Heteropolyacids and ionic liquid effect allowed tuning of the Biginelli reaction mechanism and synthesis of 3,4-dihydropyrimidin-2(1H)-one/thione derivatives in an efficient, recyclable fashion. The role of acidic strength and supported heteropolyacid is disclosed.     

Detection of the gubernacular canal and its attachment to the dental follicle may indicate an abnormal eruption status

Objectives:To evaluate and compare the detection of gubernacular canals (GC) and their characteristics in normal and abnormal tooth eruption.Materials and Methods:Patients with unerupted teeth were classified according to sex and age. Each tooth was classified according to dental group, eruption status, formation status, angulation, and GC detection. The opening of the GC in the alveolar crest and the attachment sites in relation to the dental follicle were assessed. Data were analyzed by the chi-square and Kruskal-Wallis tests, with a significance level of 5%.Results:Cone-beam computed tomography scans of 159 patients were evaluated. The final sample (N = 598) consisted of 423 teeth with normal eruption, 140 impacted teeth, and 35 teeth with delayed eruption. The overall detection rate of GC was 90.6%. These rates were 94.1%, 87.1%, and 62.9% for normal eruption, impacted teeth, and delayed eruption, respectively. GC detection rates were higher in the early stages of tooth formation in normal tooth eruption and in impacted teeth. The rate of GC detection was even lower in delayed teeth when they were angulated. Unusual attachment sites of the GC to the dental follicle were associated with abnormal eruption status.Conclusions:The results of the present study suggest that GC characteristics may indicate an abnormal eruption status.     

Influence of Ferrule,Post System,and Length on Biomechanical Behavior of Endodontically Treated Anterior Teeth

Introduction

The aim of this study was to evaluate the influence of post system, length, and ferrule on biomechanical behavior of endodontically treated anterior teeth.

Methods

The investigation was conducted by using laboratory tests and 3-dimensional finite element analysis. Eighty bovine incisors were selected and divided into 8 treatment groups (n = 10) with absence of ferrule and 2.0 mm of ferrule, restored with glass fiber post or cast post and core, and 12.0 and 7.0 mm of post length. The specimens were loaded at 135° angle, and the strain was measured by using strain gauge method. Specimens were subsequently loaded until fracture. Strain and fracture resistance results were analyzed by 3-way analysis of variance and Tukey honestly significant difference tests (α = 0.05). Three-dimensional models of a maxillary central incisor were generated with the same treatment variations used in laboratory tests. Each model was subjected to 100 N oblique loads. Results were evaluated by von Mises criterion.

Results

Ferrule was a determining factor in the strain, fracture resistance, and fracture pattern. In the absence of ferrule, the use of fiberglass posts represents a conservative choice from the standpoint of the fracture patterns observed. The length of 7 mm for cast post and cores produced high rates of root fractures. Finite element analysis showed that glass fiber post showed homogeneous stress distribution, whereas cast post showed stress concentration into root canal.

Conclusions

Post length influenced only the cast post strain and stress distribution. The ferrule groups always showed more satisfactory stress distribution and fracture resistance.     

An In Silico and an In Vitro Inhibition Analysis of Glycogen Phosphorylase by Flavonoids,Styrylchromones, and Pyrazoles

Glycogen phosphorylase (GP) is a key enzyme in the glycogenolysis pathway. GP inhibitors are currently under investigation as a new liver-targeted approach to managing type 2 diabetes mellitus (DM). The aim of the present study was to evaluate the inhibitory activity of a panel of 52 structurally related chromone derivatives; namely, flavonoids, 2-styrylchromones, 2-styrylchromone-related derivatives [2-(4-arylbuta-1,3-dien-1-yl)chromones], and 4- and 5-styrylpyrazoles against GP, using in silico and in vitro microanalysis screening systems. Several of the tested compounds showed a potent inhibitory effect. The structure–activity relationship study indicated that for 2-styrylchromones and 2-styrylchromone-related derivatives, the hydroxylations at the A and B rings, and in the flavonoid family, as well as the hydroxylation of the A ring, were determinants for the inhibitory activity. To support the in vitro experimental findings, molecular docking studies were performed, revealing clear hydrogen bonding patterns that favored the inhibitory effects of flavonoids, 2-styrylchromones, and 2-styrylchromone-related derivatives. Interestingly, the potency of the most active compounds increased almost four-fold when the concentration of glucose increased, presenting an IC₅₀ < 10 µM. This effect may reduce the risk of hypoglycemia, a commonly reported side effect of antidiabetic agents. This work contributes with important considerations and provides a better understanding of potential scaffolds for the study of novel GP inhibitors.