Regional variations and sex-related differences of stiffness in human tracheal ligaments.

PURPOSE: There have been numerous studies focused on the stiffness of tracheal cartilage. However, no research has been conducted specifically on the annular ligament, nor have any regional differences in the annular ligament been identified. The purpose of this study was to investigate the stiffness of the ligaments present between the thyroid, cricoid and tracheal cartilages. METHODS: The ligaments were identified in the cervical region of living subjects with ultrasonography. The stiffness of the ligaments was measured from the body surface using a digital palpation device (MyotonPRO). Since it is impossible to measure the entire trachea in a living subject, an additional measurement was performed on human cadavers. RESULTS: Both in vivo and cadaveric investigations found that the stiffness of annular ligaments decreased gradually from the superior to inferior parts. There was no difference in the stiffness between males and females in the superior part of the trachea. However, the stiffness of the middle and inferior parts was predominantly higher in females than in males. Furthermore, males showed significant differences in stiffness between the superior and middle parts, while females showed no significant differences. CONCLUSION: These results reveal that there are regional and sex-related differences in the stiffness of human tracheal ligaments.

Impact of COVID-19 Pandemic and Associated Restrictions on Vitamin D Status in a Large Cohort of Italian Children and Adolescents.

Background and Objectives: Vitamin D is synthesized in the skin upon sunlight exposure, showing variations with season and latitude. We aimed to investigate the influence of age, sex, and season on vitamin D status in a large pediatric cohort during the COVID-19 pandemic period and the corresponding pre-pandemic period. Materials and Methods: Retrospective data concerning subjects aged < 18 years were extracted anonymously from the large database of a reference laboratory hospital (Sassari, Northern Sardinia, Italy). Serum 25-hydroxyvitamin D [25(OH)D] levels measured during the pre-pandemic period (1 March 2018 to 30 September 2019) were compared with those detected during the pandemic period (1 March 2020 to 30 September 2021). Results: A total of 2317 samples from subjects aged < 18 years were included in the analysis, 1303 (47.9% females) of which were collected in the pre-pandemic period and 1014 (51.3% females) in the pandemic period. No significant differences in 25(OH)D levels were found between the two periods, whereas, in children aged < 2 years, levels were higher than those in children aged 11-16 years (p < 0.05). Monthly levels of 25(OH)D between pre-pandemic and pandemic periods did not differ, although significant differences were detected across months (p < 0.0001). Similarly, 25(OH)D values did not differ significantly between males and females in both periods. Marked seasonal variations were observed in males and females across all age groups. Conclusions: Serum vitamin D levels and their season-related variations were not significantly affected by the COVID-19 pandemic and associated restrictions in a large cohort of Italian children and adolescents.

The yin and yang of two opponent processes of sleep-wake regulation: Sex-associated differences in the spectral EEG markers of the drives for sleep and wake.

Although objectively measured characteristics of sleep efficiency and quality were found to be better in women than men, women more frequently than men suffer from poor or insufficient or non-restorative sleep. We explored this apparent paradox by testing the sex-associated differences in electroencephalographic (EEG) indicators of two opponent processes of sleep-wake regulation, the drives for sleep and wake. We tried to provide empirical support for the hypothesis that a stronger women's sleep drive can explain better objective characteristics of sleep quality in women than men, while a stronger women's wake drive can be an explanation of a higher frequency of sleep-related complaints in women than men. To our knowledge, this was the first attempt to examine the associations of sex with scores on the 1st and 2nd principal components of the EEG spectrum that can serve as objective spectral EEG markers of the opponent drives for sleep and wake, respectively. The particular prediction was that, in women compared to men, not only the 1st principal component score but also the 2nd principal component score could be higher (i.e. both drives could be stronger). In a sample of 80 university students (40 females), the EEG signals were recorded during 160 afternoon napping attempts (50 min or longer). The difference between male and female students in sleep latencies did not reach a statistically significant level. In accordance with our prediction, both principal component scores were found to be higher in female than in male students irrespective of sleep stage. It is likely that the influence of the wake drive is entirely overlooked in the polysomnographic studies due to the predominant contribution of the indicators of the sleep drive to the conventional objective characteristics of sleep quality. Therefore, a stronger women's sleep drive can be an explanation of women's better sleep quality in the results of polysomnographic studies. On the other hand, if a stronger women's wake drive can influence the perception of their sleep quality, this can explain their more frequent sleep-related complaints.

Sex-Related Mortality After Burns: A Scoping Review in the Sadc-Region.

Findings on mortality by sex after burns in low- and middle-income countries (LMICs) are contradictory and, where differences have been described, the reasons are often based on speculation and not on the analysis of factors that could have affected the outcome, such as patient or injury characteristics or provided care. Since the paucity of studies on burns from single LMICs is notorious, merging data from neighboring countries with similar socio-economic backgrounds might provide a larger dataset, contributing to identifying recurrent causes. This scoping review aimed therefore to analyze differences in mortality after burns between the sexes, as well as to identify aspects that could explain possible differences, in countries belonging to the South African Development Community (SADC) region. Studies in English published between 2010 and 2020 were identified according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines by searching PubMed and/or Medline, Clinical Trials and Cochrane Library, and using the screening tool "Covidence". The 13 included studies could not consistently show association between sex and mortality after burns, but contradictory findings. In the case of differences in outcome between the sexes, explanations were mainly based on speculation (e.g., hormonal differences, self-harm intention), while rarely burn specific factors were reported and included in the analysis of the mortality risk. This study indicates the need for prospective burn specific data collection in LMICs that would contribute to identifying factors associated with death.

Les résultats concernant la mortalité par sexe après brûlures dans les pays en développement (PED) sont contradictoires et, en cas de différence, les raisons sont souvent spéculatives et non basées sur l'analyse de facteurs qui auraient pu affecter le résultat, tels que les caractéristiques du patient ou de la brûlure ou les soins fournis. Étant donné la rareté des études sur les brûlures dans les PED, la fusion des données de pays voisins ayant un contexte socio-économique similaire pourrait fournir une base de données plus large contribuant à l'identification des causes récurrentes. Cette revue de cadrage visait donc à analyser les différences de mortalité après brûlures entre les sexes, ainsi qu'à identifier les aspects qui pourraient expliquer d'éventuelles différences, dans les pays appartenant à la région de la Communauté de développement de l'Afrique australe (SADC). Les études en anglais publiées entre 2010 et 2020 ont été identifiées selon les Preferred Reporting Items for Systematic Reviews and Meta-Analysis en effectuant des recherches dans PubMed et/ou Medline, Clinical Trials et Cochrane Library, et en utilisant l'outil de sélection "Covidence". Les 13 études incluses n'ont pas pu montrer de manière cohérente l'association entre le sexe et la mortalité après brûlures, mais des résultats contradictoires. Dans le cas des différences de résultats entre les sexes, les explications étaient principalement spéculatives (par exemple, différences hormonales, intention d'automutilation), tandis que les facteurs spécifiques aux brûlures étaient rarement rapportés et inclus dans l'analyse du risque de mortalité. Cette étude indique la nécessité d'une collecte prospective de données spécifiques aux brûlures dans les PED qui contribuerait à identifier les facteurs associés à la mortalité.