Hyperbaric oxygen alleviates selective domains of cognitive and motor deficits in female 5xFAD mice

Treatment of Alzheimer's disease (AD) has been limited to managing of symptoms or anti-amyloid therapy with limited results and uncertainty. Seeking out new therapies that can reverse the effects of this devastating disease is important. Hyperbaric oxygen (HBO) therapy could be such a candidate as it has been shown to improve brain function in certain neurological conditions. Furthermore, the role sex plays in the vulnerability/resilience to AD remains equivocal. An understanding of what makes one sex more vulnerable to AD could unveil new pathways for therapy development. In this study, we investigated the effects of HBO on cognitive, motor, and affective function in a mouse model of AD (5xFAD) and assessed protein oxidation in peripheral tissues as a safety indicator. The motor and cognitive abilities of 5xFAD mice were significantly impaired. HBO therapy improved cognitive flexibility and associative learning of 5xFAD females but not males, but HBO had no effect other aspects of cognition. HBO also reversed AD-related declines in balance but had no impact on gait and anxiety-like behavior. HBO did not affect body weights or oxidative stress in peripheral tissues. Our study provides further support for HBO therapy as a potential treatment for AD and emphasizes the importance of considering sex as a biological variable in therapeutic development. Further investigations into the underlying mechanisms of HBO's sex-specific responses are warranted, as well as optimizing treatment protocols for maximum benefits.

[The morphology and resilience change of upper airway in patients with OSAHS: A MSCT study]

Objective:To analyse the morphology and resilience of upper airway in patients with OSAHS using 128-slice MSCT. Method:CT imaging of the upper airway in 49 patients with OSAHS was acquired in two respiratory status (quiet respiration and Müller maneuver). The two-dimensional measurements of retropalatal and retroglossal regions, airway volume, and airway resilience were measured in patients with severe OSAHS and non-severe OSAHS. And the results were compared between those two groups. Result:① The following measurements during Müller maneuver were smaller than those during quiet respiration: the smallest cross section area of retropalatal and retroglossal region, the anteroposterior diameters(AP) and lateral diameters(L) of retropalatal region, L of retroglossal region, volume and average volume of upper airway and retropalatal area（P<0.01）.②The pharyngeal wall resilience of retropalata region was larger than those of retroglossal region in patients with severe OSAHS. The total resilience of retropalatal was larger than that of retroglossal region in patients with non-severe OSAHS. The pharyngeal wall resilience between severe and non-severe OSAHS had no significant difference. ③ L of retropalatal and retroglossal region, and average area of retropalatal region, were smaller in patients with severe OSAHS than those with non-severe OSAHS during Müller maneuver（P<0.05）.④ The cross-section of upper airway tend to be horizontal oval in retropalatal regions, and vertical oval in retroglossal regions. Conclusion:128-slice MSCT scan can achieve both positioning and quantitative analysis of the morphology and resilience changes of the upper airway in patients with OSAHS.

Management of descending necrotizing mediastinitis

BACKGROUND

Descending necrotizing mediastinitis (DNM) is uncommon, and may be lethal if not treated adequately and promptly. Delayed diagnosis of the disease is sometimes encountered in clinical practice.

METHODS

Eight consecutive patients with acute DNM were identified between 1991 and 1995, including five men and three women. The mean age was 45.8 years (range, 22-71 years). The infectious sources consisted of six esophageal perforations, one cervical cutting injury and one tonsillitis. The clinical presentations were evaluated. Diagnostic procedures including chest radiograph, sonogram and computerized tomography scans of the chest and neck were examined. Diagnosis and treatment, including culture results from drained fluids and debrided tissues, and antibiotic and supportive therapies were reviewed.

RESULTS

Six patients who underwent aggressive surgical treatment recovered well. Two patients who received supportive treatment died of sepsis alone. The cultured bacteria included: Klebsiella oxytoca, Staphylococcus aureus, Trichosporum and other mixed oral cavity flora.

CONCLUSIONS

Early diagnosis and adequate antibiotic and support therapies are essential to achieve good patient outcomes in acute descending mediastinitis. Adequate drainage and debridement, appropriate antibiotic therapy, and sufficient nutritional and respiratory support are the main treatment elements.