OBJECTIVE: To investigate the resistance to sliding (RS) in self-ligating and conventional ligation bracket systems at 5 different second-order bracket angulations by using low-stiffness alignment wires in a 3-bracket experimental model and to verify the performance of the main RS components in both systems when these wires are used. METHODS: Interactive self-ligating brackets with closed and open slides were used for the self-ligating (SL) and conventional ligation (CL) groups, respectively; elastomeric ligatures (1 mm inner diameter) were used in the latter system. The alignment wire used was 0.014 inch heat-activated NiTi (austenitic finish temperature set at 36degrees C by the manufacturer). A custom-made testing machine was used to measure frictional resistance. Tests were repeated 5 times at every angulation simulated. All data were analyzed statistically. RESULTS: The RS increased significantly with increasing angulation in both SL and CL groups (p < 0.0001). However, the RS values were significantly higher at every angulation (p < 0.0001) in the CL group. CONCLUSIONS: Despite the relevance of the binding phenomenon, ligation forces predominantly affect the RS when low-stiffness alignment wires are used.
Elastomers ; Friction ; Ligation ; Models, Theoretical ; Polymers

BACKGROUND AND PURPOSE: Intracerebral hemorrhage (ICH) accounts for approximately 10% of stroke cases. Hypertension may play a role in the pathogenesis of ICH that occurs in the basal ganglia, thalamus, pons, and cerebellum, but not in that of lobar ICH. Hypertension contributes to decreased elasticity of arteries, thereby increasing the likelihood of rupture in response to acute elevation in intravascular pressure. This study aimed to evaluate arterial stiffness (using the arterial stiffness index [ASI]) in patients with deep (putaminal and thalamic) ICH in comparison with patients with lobar ICH. METHODS: We enrolled 64 patients (mean+/-SD age: 69.3+/-10.7 years; 47 men and 17 women) among 73 who referred consecutively to our department for intraparenchymal hemorrhage and underwent brain computed tomography (CT) and cerebral angio-CT. In all the subjects, 24-hour heart rates and blood pressures were monitored. The linear regression slope of diastolic on systolic blood pressure was assumed as a global measure of arterial compliance, and its complement (1 minus the slope), ASI, has been considered as a measure of arterial stiffness. RESULTS: In the patients with deep ICH, ASI was significantly higher than in the patients with lobar ICH (0.64+/-0.19 vs. 0.53+/-0.17, P=0.04). CONCLUSIONS: Our results suggest that in deep ICH, arterial stiffening represents a possible pathogenetic factor that modifies arterial wall properties and contributes to vascular rupture in response to intravascular pressure acute elevation. Therapeutic strategies that reduce arterial stiffness may potentially lower the incidence of deep hemorrhagic stroke.
Arteries ; Basal Ganglia ; Blood Pressure ; Brain ; Cerebellum ; Cerebral Hemorrhage* ; Complement System Proteins ; Compliance ; Elasticity ; Heart Rate ; Hemorrhage ; Humans ; Hypertension ; Incidence ; Linear Models ; Male ; Pons ; Rupture ; Stroke ; Thalamus ; Vascular Stiffness*

BACKGROUND AND PURPOSE: Intracerebral hemorrhage (ICH) accounts for approximately 10% of stroke cases. Hypertension may play a role in the pathogenesis of ICH that occurs in the basal ganglia, thalamus, pons, and cerebellum, but not in that of lobar ICH. Hypertension contributes to decreased elasticity of arteries, thereby increasing the likelihood of rupture in response to acute elevation in intravascular pressure. This study aimed to evaluate arterial stiffness (using the arterial stiffness index [ASI]) in patients with deep (putaminal and thalamic) ICH in comparison with patients with lobar ICH. METHODS: We enrolled 64 patients (mean+/-SD age: 69.3+/-10.7 years; 47 men and 17 women) among 73 who referred consecutively to our department for intraparenchymal hemorrhage and underwent brain computed tomography (CT) and cerebral angio-CT. In all the subjects, 24-hour heart rates and blood pressures were monitored. The linear regression slope of diastolic on systolic blood pressure was assumed as a global measure of arterial compliance, and its complement (1 minus the slope), ASI, has been considered as a measure of arterial stiffness. RESULTS: In the patients with deep ICH, ASI was significantly higher than in the patients with lobar ICH (0.64+/-0.19 vs. 0.53+/-0.17, P=0.04). CONCLUSIONS: Our results suggest that in deep ICH, arterial stiffening represents a possible pathogenetic factor that modifies arterial wall properties and contributes to vascular rupture in response to intravascular pressure acute elevation. Therapeutic strategies that reduce arterial stiffness may potentially lower the incidence of deep hemorrhagic stroke.
Arteries ; Basal Ganglia ; Blood Pressure ; Brain ; Cerebellum ; Cerebral Hemorrhage* ; Complement System Proteins ; Compliance ; Elasticity ; Heart Rate ; Hemorrhage ; Humans ; Hypertension ; Incidence ; Linear Models ; Male ; Pons ; Rupture ; Stroke ; Thalamus ; Vascular Stiffness*

Purpose: Augmented adiposity may negatively impact sexual sphere through its metabolic effects and its detrimental impact on reproductive hormones. Moreover, a dysregulated metabolic pathway may promote apoptosis among spermatogenic cells. Based on these premises, a relation between weights loss and ameliorate semen parameters seems beneficial. To investigate if physical activity may affect semen parameters and fertility rate, a systematic literature search on major dataset has been performed. Materials and Methods: The search terms included: “Assisted reproduction therapies,” “fertility,” “semen parameters,” “sperm parameters,” and “physical activity.” This analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines and it was registered on PROSPERO (CRD42023384471). A total of 47 studies have been identified; 1 reference has been eliminated after duplication check. After preliminary screening 32 papers have been excluded. Considering the exclusion criteria, 15 full-text articles were evaluated for eligibility. After a full-text review, six studies published during a span of eight years (2014–2022) have been included in the meta-analysis. Semen parameters, pregnancy and birth rates were investigated. The revised Cochrane risk of bias tool (Rob2) has been used to check the risk of bias. Results: The number of patients enrolled in studies ranges from 17 to 521; in the end, a total of 1,637 patients have been enrolled in the study. Fertility parameters investigated were semen quality parameters and pregnancy rates and live births. A statistically significant relationship between physical exercise and sperm concentration (p=0.02), total sperm motility (p<0.01), total sperm count (p<0.01), normal morphology (p<0.01) has been established. Moreover, the study registered a statistically significant association within physical activity and total pregnancy rate (p<0.01) and live birth rate (p<0.01). Conclusions We demonstrated that physical activity is significantly associated with amelioration of semen parameters and may be crucial in improving or even reverting male infertility.