Neurological disorders in HIV in Africa: a review

Background: Neurological disorders in HIV infection are a common cause of morbidity and mortality. The aim of this paper is to provide a narrative overview of up to date information concerning neurological disorders affecting HIV infected persons in Africa.Methods: Seminal research concerning neurological disorders among HIV-infected adults in sub-Saharan Africa from prior to 2000 was combined with an in-depth search of PubMed to identify literature published from 2000 to 2017. The following Mesh terms were used. "Nervous System Diseases” "HIV Infections" and "Africa South of the Sahara" and "Seizures" or "Spinal Cord Diseases" or “Peripheral Nervous System Diseases" or "AIDS Dementia Complex" or “Opportunistic Infections" or "Immune constitution Inflammatory Syndrome” or "Stroke". Only those articles written in English were used. A total of 352 articles were identified, selected and reviewed and 180 were included in the study. These included case series, observational studies, interventional studies, guidelines and reviews with metanalyses. The author also included 15 publications on the subject covering theearlier phase of the HIV epidemic in Africa from 1987 to 1999 making a total of 195 references in the study. This was combined with extensive personal experience diagnosing and treating these neurological disorders.Results: Neurological disorders were common, typically occurring in WHO stages III/IV. These were in three main categories: those arising from opportunistic processes mostly infections, direct HIV infection and autoimmunity. The most common were those arising from direct HIV infection occurring in >50%. These included HIV-associated neurocognitive dysfunction (HAND), neuropathy and myelopathy. Opportunistic infections occurred in >20% and frequently had a 6-9-month mortality rate of 60-70%. The main causes were cryptococcus, tuberculosis, toxoplasmosis and acute bacterial meningitis. Concurrentsystemic tuberculosis occurred in almost 50%.Conclusion: Neurological disorders are common in HIV in Africa and the main CNS opportunistic infections result in high mortality rates. Strategies aimed at reducing their high burden, morbidity and mortality include early HIV diagnosis and anti-retroviral therapy (ART), screening and chemoprophylaxis of main opportunistic infections, improved clinical diagnosis and management and programme strengthening.Keywords: Neurological disorders, HIV, Africa, opportunistic infections, direct HIV infection and inflammatory disorders

The Rise of China\u27s Hacking Culture: Defining Chinese Hackers

China has been home to some of the most prominent hackers and hacker groups of the global community throughout the last decade. In the last ten years, countless attacks globally have been linked to the People’s Republic of China (PRC) or those operating within the PRC. This exploration attempts to investigate the story, ideology, institutions, actions, and motivations of the Chinese hackers collectively, as sub-groups, and as individuals. I will do this using sources ranging from basic news coverage, interviews with experts and industry veterans, secondary reportage, leaked documents from government and private sources, government white papers, legal codes, blogs and microblogs, a wide array of materials from the darker corners of the online world, and many other materials. The work will begin to sketch for the reader some of the general and specific aspects of the shadowy world of cybercrime and hacker culture in China in recent years. One of the most prevalent beliefs is that the Chinese government is in fact the one responsible, whether directly or by sponsor, for cyber-attacks on foreign systems. My careful analysis has revealed is not always the case, or at least more complex than simply labeling the group as a state actor. At the root of these attacks is a social movement of hacktivists, a patriotic sub-culture of Chinese hackers. It is incorrect to allege that all attacks are performed by state-sponsored individuals or groups, because there are many individuals and groups that are motivated by other factors

A PI3K-mediated negative feedback regulates Drosophila motor neuron excitability

Negative feedback can act as a homeostatic mechanism to maintain neuronal activity at a particular specified value. At the Drosophila neuromuscular junction, a mutation in the type II metabotropic glutamate receptor gene (mGluRA) increased motor neuron excitability by disrupting an autocrine, glutamate-mediated negative feedback. We show that mGluRA mutations increase neuronal excitability by preventing PI3 kinase (PI3K) activation and consequently hyperactivating the transcription factor Foxo. Furthermore, glutamate application increases levels of phospho-Akt, a product of PI3K signaling, within motor nerve terminals in an mGluRA-dependent manner. In humans, PI3K and type II mGluRs are implicated in epilepsy, neurofibromatosis, autism, schizophrenia and other neurological disorders; however, neither the link between type II mGluRs and PI3K, nor the role of Foxo in the control of neuronal excitability, had been previously reported. Our work suggests that some of the deficits in these neurological disorders might result from disruption of glutamate-mediated homeostasis of neuronal excitability

‘The Chaotic Science Lab’: Supporting trainee science teachers – a cross departmental project

This project supports science teachers in developing health and safety skills through the use of a virtual laboratory. In the laboratory they can carry out health and safety audits, develop their awareness of potential hazards and assess the possible risks involved. The students can visit the virtual world either individually or in groups, and then discuss the issues they have found to be a risk ‘in-world’ or later in the ‘real’ classroom. A web interface enables user registration and a user record for each session. Each session is recorded with time, date, location and scores for the user as they work through pre-programmed activities which enable the tracking and analysis of site usage. Early findings suggest that this is an intriguing and unexpected addition to the science teacher training curriculum, and that students are keen to develop the scenarios further. There are clear benefits for staff and students alike

Neurological disorders in HIV in Africa: a review

Background: Neurological disorders in HIV infection are a common cause of morbidity and mortality. The aim of this paper is to provide a narrative overview of up to date information concerning neurological disorders affecting HIV infected persons in Africa. Methods: Seminal research concerning neurological disorders among HIV-infected adults in sub-Saharan Africa from prior to 2000 was combined with an in-depth search of PubMed to identify literature published from 2000 to 2017. The following Mesh terms were used. "Nervous System Diseases\u201d "HIV Infections" and "Africa South of the Sahara" and "Seizures" or "Spinal Cord Diseases" or \u201cPeripheral Nervous System Diseases" or "AIDS Dementia Complex" or \u201cOpportunistic Infections" or "Immune Reconstitution Inflammatory Syndrome\u201d or "Stroke". Only those articles written in English were used. A total of 352 articles were identified, selected and reviewed and 180 were included in the study. These included case series, observational studies, interventional studies, guidelines and reviews with metanalyses. The author also included 15 publications on the subject covering the earlier phase of the HIV epidemic in Africa from 1987 to 1999 making a total of 195 references in the study. This was combined with extensive personal experience diagnosing and treating these neurological disorders. Results: Neurological disorders were common, typically occurring in WHO stages III/IV. These were in three main categories: those arising from opportunistic processes mostly infections, direct HIV infection and autoimmunity. The most common were those arising from direct HIV infection occurring in >50%. These included HIV-associated neurocognitive dysfunction (HAND), neuropathy and myelopathy. Opportunistic infections occurred in >20% and frequently had a 6-9-month mortality rate of 60-70%. The main causes were cryptococcus, tuberculosis, toxoplasmosis and acute bacterial meningitis. Concurrent systemic tuberculosis occurred in almost 50%. Conclusion: Neurological disorders are common in HIV in Africa and the main CNS opportunistic infections result in high mortality rates. Strategies aimed at reducing their high burden, morbidity and mortality include early HIV diagnosis and anti-retroviral therapy (ART), screening and chemoprophylaxis of main opportunistic infections, improved clinical diagnosis and management and programme strengthening. DOI: https://dx.doi.org/10.4314/ahs.v19i2.19 Cite as: Howlett WP. Neurological disorders in HIV in Africa: a review. Afri Health Sci.2019;19(2): 1953-1977. https://dx.doi.org/10.4314/ ahs.v19i2.1

A New Technique for Multidimensional Signal Compression

The problem of efficiently compressing a large number, L, of N dimensional signal vectors is considered. The approach suggested here achieves efficiencies over current pre-processing and Karhunen-Loeve techniques when both L and N are large

Neurosyphilis in Africa: A systematic review.

INTRODUCTION: Neurological involvement is one of the most important clinical manifestations of syphilis and neurological disease occurs in both early and late syphilis. The impact of HIV co-infection on clinical neurosyphilis remains unclear. The highest prevalence of both syphilis and HIV is in Africa. Therefore it might be expected that neurosyphilis would be an important and not uncommon manifestation of syphilis in Africa and frequently occur in association with HIV co-infection; yet few data are available on neurosyphilis in Africa. The aim of this study is to review data on neurosyphilis in Africa since the onset of the HIV epidemic. METHODS: We searched the literature for references on neurosyphilis in Africa for studies published between the 1st of January 1990 and 15th February 2017. We included case reports, case series, and retrospective and prospective cohort and case-control studies. We did not limit inclusion based on the diagnostic criteria used for neurosyphilis. For retrospective and prospective cohorts, we calculated the proportion of study participants who were diagnosed with neurosyphilis according to the individual study criteria. Depending on the study, we assessed the proportion of patients with syphilis found to have neurosyphilis, and the proportion of patients with neurological syndromes who had neurosyphilis. Due to heterogeneity of data no formal pooling of the data or meta-analysis was undertaken. RESULTS: Amongst patients presenting with a neurological syndrome, three studies of patients with meningitis were identified; neurosyphilis was consistently reported to cause approximately 3% of all cases. Three studies on stroke reported mixed findings but were limited due to the small number of patients undergoing CSF examination, whilst neurosyphilis continued to be reported as a common cause of dementia in studies from North Africa. Ten studies reported on cases of neurosyphilis amongst patients known to have syphilis. Studies from both North and Southern Africa continue to report cases of late stage syphilis, including tabes dorsalis and neurosyphilis, in association with ocular disease. DISCUSSION: This is the first systematic review of the literature on neurosyphilis in Africa since the beginning of the HIV epidemic. Neurosyphilis continues to be reported as a manifestation of both early and late syphilis, but the methodological quality of the majority of the included studies was poor. Future well-designed prospective studies are needed to better delineate the incidence and clinical spectrum of neurosyphilis in Africa and to better define interactions with HIV in this setting

Neurological disorders in Northern Tanzania: A 6-year prospective hospital-based case series

Background: The burden of neurological disorders is large and altered by the HIV epidemic. Objectives: We describe the pattern of neurological disorders and their association with HIV infection in adult patients attending a consultant hospital in Northern Tanzania. Methods: In this prospective cross-sectional study, we collected data on adult neurological referrals over a 6-year period between 2007-13. The odds of HIV infection, across neurological categories adjusted for age and sex, was calculated. Results: Of 2037 participants, 54.8% were male and 45.2% were female. The median age of participants was 43 years. The results for HIV screening were available for 992/2037 (48.7%) patients, of whom 306 (30.8%) were seropositive. The most frequent neurological disorders were cerebrovascular disease (19.9%), paraplegia (13.6%), and peripheral neuropathies (8%). Taken together CNS infection accounted for 278/2037 (13.6%). The adjusted odds (aOR) of HIV infection was highest amongst infections; brain abscesses (aOR 107, 95% CI 35.1-470.4) and meningitis/encephalitis (aOR 40.1, 95% CI 13.6-172.9), but also raised in cerebrovascular disease, paraplegia, peripheral neuropathies, cranial nerve palsies, seizures, cerebllar disorders, movement disorders, motor neuron disease and headache. Conclusion: The main pattern of neurological disorders in Northern Tanzania is presented. The odds of HIV infection was highest in CNS infections and in a wide range of non-communicable neurological disorders.publishedVersio

Ten-year plateau phase in human immunodeficiency virus induced motor neuron disease upon antiretroviral therapy: a first case from Eastern Africa.

We report an individual with rapidly progressive motor neuron disease (MND), phenotypically compatible with amyotrophic lateral sclerosis (ALS). The patient described in this case report proved positive for human immunodeficiency virus (HIV) and was initiated on antiretroviral therapy (ART). Following ART he clinically stabilised over 10 years and deteriorated again due to noncompliance or ART resistance. HIV infection can give rise to an MND mimic, HIV-ALS. The improvement in response to ART supports the notion that HIV-ALS is a treatable entity also in Africa. This is the first case report of a patient with HIV-ALS and long term follow up in Sub-Saharan Africa. The report raises the suggestion that an additional (retro)virus can play a role in the aetiology of ALS