Long-Term Effects of Cannabis on Brain Structure

The dose-dependent toxicity of the main psychoactive component of cannabis in brain regions rich in cannabinoid CB1 receptors is well known in animal studies. However, research in humans does not show common findings across studies regarding the brain regions that are affected after long-term exposure to cannabis. In the present study, we investigate (using Voxel-based Morphometry) gray matter changes in a group of regular cannabis smokers in comparison with a group of occasional smokers matched by the years of cannabis use. We provide evidence that regular cannabis use is associated with gray matter volume reduction in the medial temporal cortex, temporal pole, parahippocampal gyrus, insula, and orbitofrontal cortex; these regions are rich in cannabinoid CB1 receptors and functionally associated with motivational, emotional, and affective processing. Furthermore, these changes correlate with the frequency of cannabis use in the 3 months before inclusion in the study. The age of onset of drug use also influences the magnitude of these changes. Significant gray matter volume reduction could result either from heavy consumption unrelated to the age of onset or instead from recreational cannabis use initiated at an adolescent age. In contrast, the larger gray matter volume detected in the cerebellum of regular smokers without any correlation with the monthly consumption of cannabis may be related to developmental (ontogenic) processes that occur in adolescence.     

Exploring of two different equated instability resistance training programs on measure of physical fitness and lower limb asymmetry in pre-pubertal weightlifters

Background

In the postpandemic era, wearing protective masks in public places will still be an important means of blocking popular viruses in the future. The purpose of this study was to explore whether sports performance was affected by mask wearing and exercise duration during 15-min treadmill running at a speed of 75% maximal aerobic speed.

Methods

Thirty-six males were randomly divided into mask and nonmask groups. The kinematic and kinetic data were obtained at four time points (RN_0–1 min, RN_5–6 min, RN_9–10 min, and RN_14–15 min) during running. Two-way mixed ANOVA was applied to examine the effects between groups and times with Bonferroni post hoc comparison and independent samples t-test.

Results

The results showed that there was no difference between mask and nonmask group during running (p?>?0.05). As running time increased, hip joint ROM, hip joint flexion/extension max, and ankle joint plantarflexion max angles increased; knee joint flexion min and ankle joint dorsiflexion max angles decreased; average peak vertical ground reaction forces (PVGRF) increased after 9 min-running (p?<?0.05).

Conclusions

Wearing a medical protective mask does not affect the joint angle and touchdown PVGRF of lower extremities during treadmill running while affected by running time and changed after 9 min-treadmill running. Future studies will examine the effects of wearing masks during the pandemic on muscle activation and blood biochemical values during exercise.

Trial registration No. ChiCTR2000040535 (date of registration on December 1, 2020). Prospectively registered in the Chinese Clinical Trial Registry.

     

Value of high resolution ultrasonography in assessment of laryngeal lesions

Objective: The aim of this study is to evaluate the value of high resolution ultrasonography (HRUS) in diagnosis of various laryngeal lesions which already diagnosed with rigid endoscopy. Study design: Prospective study with control group. Patients and methods: Sixty-six patients were suffering from throat symptoms and pre-examined by rigid endoscopy under local anesthesia and diagnosed to have a laryngeal lesion and 32 volunteers compose the control group. All 98 persons (patients and control groups) were examined by HRUS. Results: HRUS was helpful in describing various laryngeal lesions, vocal fold polyps (17) 25.7%, glottic cancer (6) 9.1%, epiglottic enlargement (2) 3.1% and one patient had laryngocele (1.5%). HRUS was highly significant in diagnosis of subglottic lesions (10) 15.2%. Also vocal fold mobility can be demonstrated by HRUS. While interarytenoid lesions (17) 25.8% and small laryngeal lesions as vocal fold nodules (13) 19.6% were difficult to be described. Conclusion: Rigid endoscopy in laryngeal examination gives us large, bright image but it is difficult to diagnose patients with a sensitive gag reflex, patients with neck or jaw diseases or stridor and very difficult in infants and children. HRUS is an alternative method in diagnosis of some laryngeal lesions, and it is superior in the diagnosis of small subglottic lesions.     

Granulicatella elegans native valve infective endocarditis: case report and review

Granulicatella elegans is a fastidious organism that is rarely implicated as a cause of infective endocarditis. Here, we describe a patient with mitral valve prolapse who developed G. elegans endocarditis. The organism was isolated from blood cultures and the patient had mitral valvuloplasty and repair, and completed a course of 6 weeks of intravenous antibiotics with no sequela.