Mapping the Impact and Plasticity of Cortical-Cardiovascular Interactions in Vascular Disease Using Structural and Functional MRI

There is growing interest in the role of vascular disease in accelerating age-related decline in cerebrovascular structural and functional integrity. Since an increased number of older adults are surviving chronic diseases, of which cardiovascular disease (CVD) is prevalent, there is an urgent need to understand relationships between cardiovascular dysfunction and brain health. It is unclear if CVD puts the brains of older adults, already experiencing natural brain aging, at greater risk for degeneration. In this thesis, the role of CVD in accelerating brain aging is explored. Because physical activity is known to provide neuroprotective benefits to brains of older adults, the role of physical activity in mediating disease effects were also explored. Using novel neuroimaging techniques, measures of gray matter volume and cerebrovascular hemodynamics were compared between groups of coronary artery disease patients and age-matched controls, to describe regional effects of CVD on the brain. In a sub-set of patients, imaging measures were repeated after completion of a 6-month exercise training, part of a cardiac rehabilitation program, to examine exercise effects. Differences in cerebrovascular hemodynamics were measured as changes in resting cerebral blood flow (CBF) and changes in cerebrovascular reactivity (CVR) to hypercapnia (6% CO2) using a non-invasive perfusion magnetic resonance imaging technique, arterial spin labelling (ASL). We found decreased brain volume, CBF and CVR in several regions of the brains of coronary artery disease patients compared to age-matched healthy controls. The reductions in CBF and CVR were independent of underlying brain atrophy, suggesting that changes in cerebrovascular function could precede changes in brain structure. In addition, increase in brain volume and CBF were observed in some regions of the brain after exercise training, indicating that cardiac rehabilitation programs may have neurorehabiliation effects as well. Since, CBF measured with ASL is not the [gold] standard measure of functional brain activity, we examined the regional correlation of ASL-CBF to glucose consumption rates (CMRglc) measured with positron emission tomography (PET), a widely acceptable marker of brain functional activity. Simultaneous measurements of ASL-CBF and PET-CMRglc were performed in a separate study in a group of older adults with no neurological impairment. Across brain regions, ASL-CBF correlated well with PET-CMRglc, but variations in regional coupling were found and demonstrate the role of certain brain regions in maintaining higher level of functional organization compared to other regions. In general, the results of the thesis demonstrate the impact of CVD on brain health, and the neurorehabiliation capacity of cardiac rehabilitation. The work presented also highlights the ability of novel non-invasive neuroimaging techniques in detecting and monitoring subtle but robust changes in the aging human brain

Attitude towards the use of herbal medicine among traders: A moderating effect of gender and socio-economic status

This study examined the Attitude towards the use of herbal medicine among traders: a moderating effect of gender and socio-economic status. A total of 180 participants were used for the study. They comprised 90 males and 90 females. Their ages ranged from 30-70 years with the mean age of 50 and a standard deviation (SD) of 11.9. They were selected through stratified random sampling techniques from Eke Awka, central market in Awka , Anambra state. The result of the study showed that there was no significant difference on attitude of traders towards the use of herbal medicine across gender. The result also showed that there was no significant difference on attitude of traders towards the use of herbal medicine across the three levels of socio-economic statues. The result finally showed that there was no significant interactive effect of gender and socio-economic statues on attitude of traders towards the use of herbal medicine across gender.Based on the above findings, this study recommends that the federal government through the ministry of establishment should encourage the administration and the use of herbal medicine in Nigeria as alternative to orthodox medicine

Christen und Muslime im Gebet

This work aims to explore the possibilities of multireligious encounter of Muslims and Christians, in view of the liturgical worship, a problem which is highly controversial. It studies the ritual acts of the Muslims and Christians in the celebration of the daily worship as an expression of their belief in God's presence, mercy and goodness as outlined by Vatican Council II (Nostra aetate 3).Die Arbeit hat einen Kernbereich der beiden Weltreligionen Christentum und Islam, ihren öffentlichen gemeinsamen Gebetsgottesdienst, zum Thema. Zum Ausgangspunkt nimmt sie die Feststellung des Zweiten Vatikanischen Konzils: Mit Hochachtung betrachtet die Kirche auch die Muslime, die den alleinigen Gott anbeten, den lebendigen und in sich seienden, barmherzigen und allmächtigen, den Schöpfer Himmels und der Erde, der zu den Menschen gesprochen hat (Nostra aetate 3). Die Arbeit möchte einen Beitrag zum Dialog leisten, indem sie die geltenden Formen des täglichen Wortgottesdienstes in beiden Religionen untersucht und miteinander vergleicht, um Möglichkeiten, gemeinsam zu beten, aufzuzeigen

Effect of Corruption on Economic Development in Nigeria

Corruption, the evil of our time in Nigeria has increased in both quality and intensity with its devastating effects on human development. The endemic nature of corruption in Nigerian society constitutes one of the greatest threats in the living standards of citizenry. Thousands and millions of Nigerians are uneducated, unemployed and living in abject poverty due to the mismanagement of the national wealth and embezzlement of public funds. It is within this trend that this paper will examine the causes, effects and explores strategic measures in the management of this social problem in Nigeria. This paper recommends that the menace of corruption can be tackled in Nigeria through adoption and implementation of more stringent measures

Attitudinal Factors Associated with Prostate Cancer among Adult Males in South Eastern Nigeria

Prostate cancer is one of the most common and lethal cancers in the world. The incidence of prostate cancer has been increasing in recent years. Beliefs and awareness towards prostate cancer screening among men is very crucial for early detection and management of the condition. In Nigeria, it is the most common male cancer and maybe as high as that seen in African Americans in the united states. This paper examines the knowledge, belief and attitudes of men in Nigeria towards prostate cancer and prostate cancer screening for the peaceful existence in our society

Active tuberculosis among adult HIV-infected patients accessing antiretroviral therapy in a tertiary health facility in Lafia, northcentral Nigeria

Background: Tuberculosis and Human Immunodeficiency Virus (HIV) co-infection is a major problem in Nigeria and other countries that are ravaged by a high burden of both diseases. The World Health Organization (WHO) reports that the risk of developing active tuberculosis (TB) among people living with HIV is 16-27 times that of HIV negative persons. Although antiretroviral therapy (ART) reduces the risk of developing TB, there are factors which predispose those on ART to TB. This study sought to determine the prevalence of TB among adults on ART in our facility and identify the predisposing factors. Methodology: This was a retrospective study utilizing data from clinical records (folders and electronic) of adult HIV patients who are accessing ART in our facility and have been on ART for at least 6 months. A proforma was used to collect data including demographic, clinical, ART and laboratory information of the patients. The data were entered into SPSS version 23 and analyzed using descriptive statistics and bivariate analysis. Associations were tested using Chi square with 95% confidence level. Results: A total of 457 patients were studied, aged 18-69 years (mean age 38.3± 10 years), and 72.4% females. Majority were married (81%), unemployed (53.8%), had mean baseline CD4 cell count of 267.4 ± 185 cells/mm3 and a mean duration on ART of 100.9± 39 months. Seventeen point three percent of the patients had a previous history of TB before or within 6 months of commencement of ART. Thirteen (2.8%) of the patients had active TB while on ART. Majority of those who had active TB were females (76.9%), married (76.9%), unemployed (46%), had no previous history of TB (53.8%), baseline CD4 cell count of ≤ 350 cells/mm3 and were on first line ART medication. There was however no significant statistical association of active TB with any of these factors. Conclusion: Few patients had active TB while on ART in this study. The high frequency of TB in those who had low baseline CD4 cell count and baseline WHO stage shows the importance of early initiation of ART in people living with HIV (PLHIV). There is need for regular screening of PLHIV for TB and innovative approaches to get people with HIV to know their TB status as well as early commencement of ART. Keywords: Human immunodeficiency virus, Active Tuberculosis, Antiretroviral therapy

A noninvasive method for quantifying cerebral blood flow by hybrid PET/MRI

Although PET with 15O-water is the gold standard for imaging cerebral blood flow (CBF), quantification requires measuring the arterial input function (AIF), which is an invasive and noisy procedure. To circumvent this problem, we propose a noninvasive PET/MRI approach that eliminates the need to measure AIF by using global CBF determined by phase-contrast (PC) MRI as a reference region. This approach not only is noninvasive but also involves no additional imaging time, because PC MRI and 15O-water PET are acquired simultaneously. The purpose of this study was to test the accuracy of this hybrid method in an animal model in which AIF was measured directly and CBF was varied by changing the arterial CO2 tension. Methods: PET and MRI data were simultaneously acquired in juvenile pigs at hypocapnia (n 5 5), normocapnia (n 5 5), and hypercapnia (n 5 4). CBF was measured by the MRI reference method and by PET alone using an MRI-compatible blood sampling system to measure AIF. Results: Global CBF estimates from PC MRI and 15O-water PET agreed well, with a correlation coefficient of 0.9 and a slope of 0.88. Strong positive correlations (R2 . 0.96) were also found between regional CBF generated by the PET-only and the MRI-reference methods. Conclusion: These findings demonstrate the accuracy of this hybrid PET/MRI approach, which might prove useful in patients for whom obtaining accurate CBF measurements is challenging

Mapping long-term functional changes in cerebral blood flow by arterial spin labeling

Although arterial spin labeling (ASL) is appealing for mapping long-term changes in functional activity, inter-sessional variations in basal blood flow, arterial transit times (ATTs), and alignment errors, can result in significant false activation when comparing images from separate sessions. By taking steps to reduce these sources of noise, this study assessed the ability of ASL to detect functional CBF changes between sessions. ASL data were collected in three sessions to image ATT, resting CBF and CBF changes associated with motor activation (7 participants). Activation maps were generated using rest and task images acquired in the same session and from sessions separated by up to a month. Good agreement was found when comparing between-session activation maps to within-session activation maps with only a 16% decrease in precision (within-session: 90 ± 7%) and a 13% decrease in the Dice similarity (within-session: 0.75 ± 0.07) coefficient after a month. In addition, voxel-wise reproducibility (within-session: 4.7 ± 4.5%) and reliability (within-session: 0.89 ± 0.20) of resting grey-matter CBF decreased by less than 18% for the betweensession analysis relative to within-session values. ATT variability between sessions (5.0 ± 2.7%) was roughly half the between-subject variability, indicating that its effects on longitudinal CBF were minimal. These results demonstrate that conducting voxel-wise analysis on CBF images acquired on different days is feasible with only modest loss in precision, highlighting the potential of ASL for longitudinal studies

Schizophrenia syndrome due to C9ORF72 mutation case report: a cautionary tale and role of hybrid brain imaging!

Background: Frontal variant frontotemporal dementia is a common cause of presenile dementia. A hexanucleotide expansion on chromosome 9 has recently been recognized as the most common genetic mutation cause of this illness. This sub-type tends to present psychiatrically with psychosis being a common presenting symptom before the onset of cognitive changes or brain atrophy. A few case series have been published describing the prominence of early psychotic symptoms, and lack of clear brain atrophy on clinical brain imaging imposing a challenge in reaching early accurate diagnosis. In this report, we present a case whereby the diagnosis of Schizophrenia syndrome was made and the patient was treated for years with multiple interventions for that syndrome before reaching the accurate diagnosis of Frontal variant frontotemporal dementia due to hexanucleotide expansion on chromosome 9. This diagnosis was confirmed after genetic testing and findings on a hybrid Positron Emission Tomography/Magnetic Resonance Imaging scanning. Case summary: A 60-year-old female diagnosed with schizophrenia at age 50 after presenting with delusions and hallucinations, which proved to be refractor to several lines of pharmacological and non-pharmacological interventions including electroconvulsive therapy. Patient had a history of post-partum psychosis in her 20s. She was referred to cognitive neurology due to progressive decline in function. While clinical structural brain imaging data were not adequate to support an alternative neurological diagnosis, careful inquiry elicited a history of psychotic illness followed by progressive decline in a sister. Genetic testing confirmed hexanucleotide expansion on chromosome 9 mutation. The patient was offered a state-of-the-art FD-Glucose Positron Emission Tomography/Magnetic Resonance Imaging scan available at our centre. While volumetric Magnetic Resonance Imaging scan did not show volume loss in frontotemporal areas, the hybrid scan showed regionally specific deficit in FD-Glucose Positron Emission Tomography affecting medial superior frontal, insula, inferior temporal, thalamus, and anterior cingulate cortex consistent with behavioral variant frontotemporal dementia. Conclusions: This case highlights the importance of considering Frontal variant frontotemporal dementia due to hexanucleotide expansion on chromosome 9 when facing relatively late-onset, refractory schizophrenia-like syndrome. Careful history from all available sources to elicit family history of similar presentation is very important. Genetic testing and functional brain imaging can aid in confirming the diagnosis and potentially streamlining the management of these cases

Towards SAMBA: Segment Anything Model for Brain Tumor Segmentation in Sub-Sharan African Populations

Gliomas, the most prevalent primary brain tumors, require precise segmentation for diagnosis and treatment planning. However, this task poses significant challenges, particularly in the African population, were limited access to high-quality imaging data hampers algorithm performance. In this study, we propose an innovative approach combining the Segment Anything Model (SAM) and a voting network for multi-modal glioma segmentation. By fine-tuning SAM with bounding box-guided prompts (SAMBA), we adapt the model to the complexities of African datasets. Our ensemble strategy, utilizing multiple modalities and views, produces a robust consensus segmentation, addressing intra-tumoral heterogeneity. Although the low quality of scans presents difficulties, our methodology has the potential to profoundly impact clinical practice in resource-limited settings such as Africa, improving treatment decisions and advancing neuro-oncology research. Furthermore, successful application to other brain tumor types and lesions in the future holds promise for a broader transformation in neurological imaging, improving healthcare outcomes across all settings. This study was conducted on the Brain Tumor Segmentation (BraTS) Challenge Africa (BraTS-Africa) dataset, which provides a valuable resource for addressing challenges specific to resource-limited settings, particularly the African population, and facilitating the development of effective and more generalizable segmentation algorithms. To illustrate our approach's potential, our experiments on the BraTS-Africa dataset yielded compelling results, with SAM attaining a Dice coefficient of 86.6 for binary segmentation and 60.4 for multi-class segmentation.Comment: 13 pages, 6 figures, 2 table