Zwerchfellultraschall zur Vorhersage des Weaning-Versagens – „absence of evidence is not evidence of absence“

Die Anaesthesiologie -     

Methamphetamine Exposure Combined with HIV-1 Disease or gp120 Expression: Comparison of Learning and Executive Functions in Humans and Mice

Methamphetamine dependence is a common comorbid condition among people living with HIV, and may exacerbate HIV-associated neurocognitive disorders. Animal models of neuroAIDS suggest that the gp120 protein may also cause cognitive impairment. The present work evaluated the separate and combined effects of HIV/gp120 and methamphetamine on learning and executive functions in both humans and transgenic mice. Human participants were grouped by HIV serostatus (HIV+ or HIV−) and lifetime methamphetamine dependence (METH+ or METH−). A neurocognitive test battery included domain-specific assessments of learning and executive functions. Mice (gp120+ and gp120−) were exposed to either a methamphetamine binge (METH+) or saline (METH−), then tested in the attentional-set-shifting task to assess learning and executive functions. In humans, HIV status was associated with significant impairments in learning, but less so for executive functions. The frequency of learning impairments varied between groups, with the greatest impairment observed in the HIV+/METH+ group. In mice, gp120 expression was associated with impairments in learning but not reversal learning (executive component). The greatest proportion of mice that failed to complete the task was observed in the gp120+/METH+ group, suggesting greater learning impairments. Our cross-species study demonstrated that HIV in humans and gp120 in mice impaired learning, and that a history of methamphetamine exposure increased the susceptibility to HIV-associated neurocognitive deficits in both species. Finally, the similar pattern of results in both species suggest that the gp120 protein may contribute to HIV-associated learning deficits in humans.     

An active lifestyle is associated with better neurocognitive functioning in adults living with HIV infection

Studies of healthy adults show that engagement in physical, social, and mental activities is associated with better cognitive outcomes, suggesting that these activities may increase cognitive reserve. Given the prevalence and real-world impact of HIV-associated neurocognitive disorders (HAND), the present study examined the association between neurocognitive outcomes and self-reported proxies for physical exercise, social activity, and mental activity (employment was used as a proxy for mental activity) among 139 HIV-infected adults (M _age = 48.7; 48 % age 50+). Participants completed a neuromedical and neuropsychological battery and were classified based on the number of self-reported active lifestyle factors (ALFs; 0 to 3), including physical exercise, social activity, and current employment. The association between ALFs and both demographically adjusted average neuropsychological T-scores and HAND diagnoses was examined. Results revealed that an increased number of ALFs were associated with better global neurocognitive performance as well as a lower prevalence of HAND. These cross-sectional findings suggest that an active engagement in life may bolster neurocognitive functioning, perhaps by enhancing cognitive and/or brain reserve. However, an alternative explanation might be that persons with better neurocognitive functioning are more inclined and able to engage in these life activities. Future studies should utilize neuroimaging methodology, longitudinal data, and interventional approaches to establish cause–effect relationships and uncover the neural mechanisms whereby physical, social, and mental stimulation may protect neurocognition via cognitive reserve among those living with HIV.     

Neurocognitive impairment associated with predominantly early stage HIV infection in Abuja,Nigeria

Detailed neuropsychological testing was performed on 133 human immunodeficiency virus (HIV) seropositive (SP) and 77 HIV seronegative (SN) individuals, 86 % with early stage HIV infection in Nigeria, to determine the frequency of HIV-related neurocognitive impairment among the HIV-infected group. The tests were administered to assess the following seven ability domains: speed of information processing, attention/working memory, executive functioning, learning, memory, verbal fluency, and motor function motor. Demographically corrected individual test scores and scores for each domain or reflecting a global deficit (a global deficit score, or GDS) were compared for the SP and SN groups. SP participants were older, had fewer years of education, were more likely to be married, differed in ethnicity, and had higher depression scores than SN individuals. Within the seven ability domains, SP performed worse than SN with respect to speed of information processing, executive function, learning, memory, and verbal fluency and also on the global measure. SP were also more frequently impaired on tests of SIP, and there was a borderline increase in the frequency of global impairment. On the individual tests, SP performed worse than SN on four tests that assessed learning, verbal fluency, memory, and motor function (the Timed Gait). SP subjects, however, performed better than SN on the Finger-tapping test, also a motor task. Performance by SP subjects was not associated on the timed gait which showed a borderline statistically significant correlation with CD4 counts. However, there were significant correlations between viral load measurements and individual tests of speed of information processing, executive function, learning, and verbal fluency and with overall executive function and a borderline correlation with the GDS. Depression scores for SP were associated with impairment on only a single test of executive function. These results demonstrate the ability of these assessments to identify areas of impairment that may be specifically linked to a history of HIV infection among individuals in Nigeria. Confirmation of these findings awaits analyses using data from a larger number of control subjects.     

Stock-outs! Improvisations and processes of infrastructuring in Uganda’s HIV/Aids and malaria programmes

ABSTRACT

This paper examines the stock-outs of medicines and diagnostic devices in Uganda. Our aim is to trace and compare interruptions in the supply of antiretrovirals and Rapid Diagnostic Tests in order to provide an ethnographic account of the complex role that improvisations play within global health infrastructures. We will argue that the fragmented and mobile infrastructures of these key global health technologies require and necessitate improvisations by the different actors involved as well as on almost all levels of the Ugandan health-care system. The extent and abundance of improvisations in itself works to acquire infrastructural capacities, a process that we will call the infrastructuring of care and treatment. We will also show how this process of infrastructuring of care and treatment – here rendered visible through improvisations – produces new dilemmas and uncertainties. Our approach to infrastructure challenges technocratic overtones prevalent in current debates around the much-needed strengthening of health systems. Our study of stock-outs aims to show how the infrastructure of under-resourced health systems is maintained by a complex nexus of socio-material practices and improvisations.     

Lower extremity manifestations of spasticity in chronic spinal cord injury

The prevalence of various manifestations of spasticity from questionnaire responses and from clinical examination of chronic spinal cord injured patients is reported. Extensor spasms, flexor withdrawal spasms, and clonus were reported by most subjects. Those with incomplete lesions reported more interference with activities, more pain, and less functional usefulness, than did those with complete lesions. Extensor spasms were reported to interfere more with transfers, whereas flexor withdrawal spasms were reported to be more frequent at night and to interfere more with sleep. Increased muscle tone was observed more often in extensor than in flexor muscles. Those with incomplete lesions had more hypertonus and more limited passive joint movements than did those with complete lesions. Flexor withdrawal reactions and extensor spasms were also more pronounced in those with incomplete lesions, particularly those with Frankel grade C lesions.     

Antibody-Targeted Liposomes for Enhanced Targeting of the Blood-Brain Barrier

Pharmaceutical Research - The blood-brain barrier (BBB) hinders therapeutic delivery to the central nervous system (CNS), thereby impeding the development of therapies for brain injury and disease....