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151.
152.

Objective

To explore the normal variation of asymmetry in mandibles of children in the age group of 1 to 12 years.

Materials and Methods

The study group consisted of 92 cadaveric mandibles of children with a dental age of 1 to 12 years old in possession of ACTA (Academic Centre for Dentistry Amsterdam), Faculty of Dentistry, the Netherlands. 3D models of the mandibles were obtained from CT-scans and hemimandibular volumes of all mandibles were calculated. The condylar height, ramus height, mandibular body length and the gonial angle were bilaterally determined using a novel landmark-based method, and the degree of asymmetry was calculated.

Results

No relationship was found between dental age and asymmetry of the studied parameters (P < .05). The highest degree of asymmetry was found in the ramus height, whereas the gonial angle presented the lowest degree of asymmetry. A positive correlation was found between the asymmetry of the hemimandibular volume vs the height of the ramus (P < .05) and the length of the mandibular body (P < .05). An inverse correlation was found between the asymmetry of the ramus height vs the condylar height (P < .05), mandibular body length (P < .05) and gonial angle (P < .05).

Conclusions

Mandibular asymmetries in children did occur (9.8% of the included mandibles presented with a relevant overall asymmetry of ≥3%) and were unrelated to age. The different segments of the mandible seem to compensate for each other, in order to maintain a functional equilibrium.  相似文献   
153.
Objectives

Tooth clenching has been suggested to be related to temporomandibular pain. However, the electromyographic characteristics of daytime clenching episodes have been minimally investigated. This study aimed to analyze the frequency, amplitude, and duration of daytime clenching episodes in patients with masticatory muscle pain and pain-free individuals.

Methods

Fifteen women with masticatory muscles myalgia (MP group, mean ± SD age = 26.4 ± 7.6 years) matched for age to 18 pain-free women (CTR group, mean ± SD age = 25.3 ± 2.8 years) were submitted to three different ability tasks (filling out questionnaires for 40 min, reading for 20 min, and playing a videogame for 20 min). The electromyographic activity periods (AP) of the right masseter greater than 10 % (AP10), 20 % (AP20), and 30 % (AP30) of the maximum voluntary contraction were analyzed.

Results

The mean frequencies of AP10, AP20, and AP30 were greater in MP than in CTR individuals (all p < 0.05). The mean duration of AP10 was higher in MP group than CTR group only while filling out the questionnaires (p = 0.0033). CTR group had an increased frequency and duration of AP10 while playing the videogame than while reading a magazine. The ability tasks did not affect the muscle activity in the MP group.

Conclusions

Individuals with masticatory muscle pain have an increased frequency of both high and low-intense daytime clenching episodes. The type of ability task affects the frequency and the duration of clenching episodes only in pain-free individuals.

Clinical relevance

Clinicians should recognize that the frequency and intensity of daytime clenching are noticeably increased in individuals with masticatory muscle pain in order to better tailor treatment.

  相似文献   
154.
This study compared the apical leakage of roots obturated with gutta-percha using either a dual-cure resin based cement (Panavia F) or an epoxy-resin sealer (Thermaseal plus) with or without the application of an acidic primer (ED Primer). Eighty-six single rooted canine teeth were decoronated, cleaned, and shaped by using hand and rotary instruments, randomly divided into four groups, and obturated as follows: group A (n = 20): ED Primer applied followed by thermoplastized obturation with gutta-percha and Thermaseal Plus sealer; group B (n = 20): thermoplastized obturation with gutta-percha and Thermaseal Plus; group C (n = 20): ED primer applied followed by thermoplastized obturation with gutta-percha and Panavia F; group D (n = 20): thermoplastized obturation with gutta-percha and Panavia F. Both a negative control (n = 3; entire root coated with wax) and a positive control (n = 3; obturated with only a fitted master cone) were included in the study. Groups A, B, C, D, and the controls were immersed in molten sticky wax, leaving the apical 2-mm exposed, and quickly chilled. All teeth were immersed in 1% methylene blue dye solution for 10 days, rinsed, and sectioned longitudinally. Apical dye penetration was measured stereomicroscopically at 10-fold magnification. The analysis of variance and Duncan Multiple Range were used for result analysis. The specimens obturated with gutta-percha and an epoxy-resin sealer (with or without an acidic primer) demonstrated significantly less linear dye penetration than specimens obturated with gutta-percha and the dual-cure, resin-based cement (with or without an acidic primer).  相似文献   
155.
Direct-acting antivirals (DAAs) for the treatment of HCV have dramatically increased the rate of sustained virological response: patients not achieving sustained virological response represent a challenge and rates of late recurrent viremia are very low. We describe here the first case of a very late HCV relapse, following an atypical kinetics (characterized by a spontaneous but transient HCV clearance after an early virological relapse), in a HIV co-infected patient treated with DAAs. Optimal adherence to the therapy was well documented and a phylogenetic analysis ruled out a possible reinfection from a different HCV strain. In conclusion, our case underlines the importance of a long follow-up (>?48 weeks) after DAAs therapies in HCV–HIV co-infected patients who might benefit the most from a very rigorous virological surveillance.  相似文献   
156.
An optimized method for the synthesis of thioacetamide (TA) in relation to the consumption of materials and energy, which reduces the production of waste and minimizes costs, is hitherto presented. The most important highlight of this work is the use of an inexpensive and readily accessible reactant for the thionation process (i.e. phosphorus pentasulfide, P4S10), combined with both alumina as solid support and a non-conventional microwave (MW) irradiation technique. In addition to this, Response Surface Methodology (RSM) was used to optimize the entire procedure of the synthesis for simultaneous tripled-maximization of Yield (ε), Mass Intensity (MI) and Mass Productivity (MP). Acetamide (AC)/P4S10 molar ratio, time and temperature of reaction were chosen as independent variables; while ε, MI and MP were chosen as responses. The determination of these green metrics parameters allow to evaluate the sustainability of the reaction and compare with other methodologies. A quadratic regression model was derived with satisfactory prediction. Tripled optimization with desirability function predicts a maximum ε of 100%, maximum MI of 29.00 kg/kg and a maximum MP of 3.45% under the following experimental conditions: AC/P4S10 molar ratio of 2.10, time of irradiation of 14 min and a temperature 140 °C.  相似文献   
157.
158.
Magnetic resonance imaging (MRI) is the current gold standard for the diagnosis of brain tumors. However, despite the development of MRI techniques, the differential diagnosis of central nervous system (CNS) primary pathologies, such as lymphoma and glioblastoma or tumor‐like brain lesions and glioma, is often challenging. MRI can be supported by in vivo magnetic resonance spectroscopy (MRS) to enhance its diagnostic power and multiproject‐multicenter evaluations of classification of brain tumors have shown that an accuracy around 90% can be achieved for most of the pairwise discrimination problems. However, the survival rate for patients affected by gliomas is still low. The High‐Resolution Magic‐Angle‐Spinning Nuclear Magnetic Resonance (HR‐MAS NMR) metabolomics studies may be helpful for the discrimination of gliomas grades and the development of new strategies for clinical intervention. Here, we propose to use T2‐filtered, diffusion‐filtered and conventional water‐presaturated spectra to try to extract as much information as possible, fusing the data gathered by these different NMR experiments and applying a chemometric approach based on Multivariate Curve Resolution (MCR). Biomarkers important for glioma's discrimination were found. In particular, we focused our attention on cystathionine (Cyst) that shows promise as a biomarker for the better prognosis of glioma tumors.  相似文献   
159.
The United Nations Convention on the Rights of Persons with Disabilities Defines stigma as the process of social oppression barring persons with mental illness from enjoying social interaction through discrimination, exclusion and denial of human and social rights. Modern stereotypes still portray the mentally ill as guilty, unpredictable and violent. Observational studies report how healthcare professionals, including nurses, are often part of the stigma. Such phenomenon belittles the needs of people seeking mental care. The aim of this study is to describe attitudes held by psychiatric nurses and mental care professionals from different care settings of an Italian Healthcare Facility, towards the mentally ill and to identify any associated factors. Mental health care professionals were recruited for this observational study from 10 Italian different psychiatric care units. The Italian version of the Community Attitudes Mentally Ill inventory (CAMI-I) was validated and used for this study. 120 completed questionnaires were deemed valid. Optimal internal consistency (α = 0.856) was measured by calculating Cronbach's Alpha for the CAMI-I. Demographic variables were correlated to items grouped into three factors of the CAMI-I (authoritarian attitudes, benevolence, social restrictiveness). Parametric test (ANOVA) highlight significant differences between CAMI-I results for different demographic variables. Significant data were obtained by comparing responses for each factor of the CAMI-i per professional profile. All healthcare professionals studied show sensitivity and positive attitude towards mental illness. Positive approaches to mental illness contribute towards easing therapeutic care and recovery in patient-centred care. CAMI-I will be a useful tool to identifying discriminatory approaches and sensitize health professionals in Italy.  相似文献   
160.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to have a significant impact on global public health. Multiple mechanisms for SARS-CoV-2 cell entry have been described; however, the role of transferrin receptor 1 (TfR1) in SARS-CoV-2 infection has received little attention. We used ferristatin II to induce the degradation of TfR1 on the surface of Vero cells and to study the consequences of such treatment on the viability of the cells and the replication of SARS-CoV-2. We demonstrated that ferristatin II is non-toxic for Vero cells in concentrations up to 400 µM. According to confocal microscopy data, the distribution of the labeled transferrin and receptor-binding domain (RBD) of Spike protein is significantly affected by the 18h pretreatment with 100 µM ferristatin II in culture medium. The uptake of RBD protein is nearly fully inhibited by ferristatin II treatment, although this protein remains bound on the cell surface. The findings were well confirmed by the significant inhibition of the SARS-CoV-2 infection of Vero cells by ferristatin II with IC50 values of 27 µM (for Wuhan D614G virus) and 40 µM (for Delta virus). A significant reduction in the infectious titer of the Omicron SARS-CoV-2 variant was noted at a ferristatin II concentration as low as 6.25 µM. We hypothesize that ferristatin II blocks the TfR1-mediated SARS-CoV-2 host cell entry; however, further studies are needed to elucidate the full mechanisms of this virus inhibition, including the effect of ferristatin II on other SARS-CoV-2 receptors, such as ACE2, Neuropilin-1 and CD147. The inhibition of viral entry by targeting the receptor on the host cells, rather than the viral mutation-prone protein, is a promising COVID-19 therapeutic strategy.  相似文献   
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