Eo Sanya

Effect of cold face stimulation on cerebral blood flow in humans.

BACKGROUND AND PURPOSE In humans, activation of the diving reflex by a cold stimulus to the face results in bradycardia, peripheral vasoconstriction and an increase in blood pressure. However, responses of the cerebral blood flow have not yet been evaluated. We undertook this study to assess the effect of cold face stimulation on the cerebral circulation in humans. METHODS Seventeen healthy volunteers, aged 27+/-5 years were evaluated during application of a cold stimulus (0 degrees C) to the forehead for 60s. We continuously monitored mean arterial pressure (MAP), mean flow velocity (MFV) of the middle cerebral artery, cardiac output, skin blood flow, heart rate and end-tidal CO2. Total peripheral resistance (TPR) was calculated as MAP divided by cardiac output. Cerebrovascular resistance index (CVRi) was calculated as MAP divided by MFV. RESULTS Cold face stimulation did not significantly affect cardiac output but resulted in significant decreases in heart rate and skin blood flow and an increase in MAP. MFV in the mid-cerebral artery showed a slight, but significant increase. The maximum increase in CVRi (14.2+/-11.4%) was significantly (P<0.01) less than the maximum increase in TPR (23.9+/-5.7%). End-tidal CO2 did not change significantly during the cold stimulation. CONCLUSIONS In contrast to other sympathetic stimulations (e.g. lower body negative pressure), facial cooling results in an increase in cerebral blood flow. The amount of cerebral vasoconstriction was less than the amount of total peripheral vasoconstriction. These results suggest that although there is some constriction of the cerebral resistance vessels during cold face stimulation, cerebral perfusion was maintained, possibly by opposing parasympathetic activation.

Abnormal heart rate and blood pressure responses to baroreflex stimulation in multiple sclerosis patients

Cardiovascular autonomic neuropathy has been previously reported in patients with multiple sclerosis (MS) using standard reflex tests. However, no study has separately evaluated both parasympathetic and sympathetic cardiovascular autonomic regulation. We therefore assessed the baroreflex-mediated vagal and sympathetic control of the heart rate and sympathetic control of the blood vessels in MS patients using sinusoidal neck stimulation.We studied 13 multiple sclerosis patients aged 28–58 years and 18 healthy controls aged 26–58 years. The carotid baroreflex was stimulated by sinusoidal neck suction (0 to –30 mmHg) at 0.1 Hz to assess the autonomic control of the heart and blood vessels, and at 0.2 Hz to assess the vagal control of the heart. Continuous recordings were made of blood pressure, electrocardiographic RR-interval and respiration, with breathing paced at 0.25 Hz. Spectral analysis was used to evaluate the magnitude of the low frequency (LF, 0.03–0.14 Hz) and high frequency (HF, 0.15–0.50 Hz) oscillations in RR-interval and blood pressure in response to the sinusoidal baroreceptor stimulation. Responses to the applied stimulus were assessed as the change in the spectral power of the RR-interval and blood pressure fluctuations at the stimulating frequency from the baseline values.The increase in the power of 0.1 Hz RR-interval oscillations during the 0.1 Hz neck suction was significantly smaller (p<0.01) in the MS patients (4.47±0.27 to 5.62±0.25 ln ms2) than in the controls (4.12±0.37 to 6.82±0.33 ln ms2). The increase in the power of 0.1 Hz systolic BP oscillations during 0.1 Hz neck suction was also significantly smaller (p<0.01) in the MS patients (0.99±0.19 to 1.96±0.39mmHg2) than in the healthy controls (1.27±0.34 to 9.01±4.10mmHg2). Neck suction at 0.2 Hz induced RR-interval oscillations at 0.2 Hz that were significantly smaller (p<0.05) in the patients (3.22±0.45 ln ms2) than in the controls (5.27±0.29 ln ms2). These results indicate that in MS patients, baroreflex dysfunction is not only restricted to the cardiovagal limb of the baroreflex, but that the sympathetic modulation of the blood vessels is also affected.

Impairment of parasympathetic baroreflex responses in migraine patients

Objectives –  The aim of this study was to assess baroreflex regulation of the heart rate and blood vessels in migraine patients in comparison with healthy controls.

Impaired cardiovagal and vasomotor responses to baroreceptor stimulation in type II diabetes mellitus

Background In diabetic patients, impairment of the cardiovagal limb of the baroreflex has been well established. However, the role of sympathetic mediated baroreflex vasomotor control of the blood vessels is not well defined. We therefore assessed the vasomotor responses to sinusoidal baroreceptor stimulation in diabetic patients.

Interest in neurology during medical clerkship in three Nigerian medical schools.

BackgroundThis study sought to ascertain perception of Nigerian medical students of neurology in comparison with 7 other major medical specialties. To also determine whether neurology was the specialty students consider most difficult and the reasons for this and to appraise their opinion on how neurosciences and neurology were taught in their different universities.MethodsSelf-administered questionnaires were used to obtain information from randomly selected clinical students from 3 medical colleges in Nigeria (University of Ibadan, Ibadan; University of Ilorin, Ilorin; Ladoke Akintola University of Technology, Osogbo).ResultsOf 320 questionnaires sent out, 302 were returned given 94% response rate. Students felt they knew neurology least of all the 8 medical specialties, and were not confident of making neurological diagnoses. About 82% of the students indicated they learnt neurology best from bedside teaching, followed by use of medical textbooks. Close to 15% found online resources very useful for learning neurology and 6% indicated that group discussion was quite useful in the acquisition of knowledge on neurology. Histology and biochemistry were the preclinical subjects participants opined were least useful in learning neurology. The most frequent reasons students felt neurology was difficult were problems with understanding neuroanatomy (49%), insufficient exposure to neurological cases (41%), too many complex diagnoses (32%) and inadequate neurology teachers (32%).ConclusionsNigerian medical students perceived neurology as the most difficult medical specialty and are not interested in specializing in it. Neurology education could be improved upon by provision of more bedside tutorials and increased availability of online resources to enhance learning. There is need to emphasize increased frequency of small group discussions amongst students so that they will be used to teamwork after graduation.

Ischemic stroke following abuse of Marijuana in a Nigerian adult male

Cannabis is the most widely used illicit drug among adolescents and young adults. Despite its widespread use, only a few reports exist on the association of cannabis use and stroke. A 26-year-old Nigerian male, developed right-sided ischemic stroke few hours after smoking three wraps of cannabis. He had smoked cannabis consistently for the past 4 years prior to the development of the stroke. Known stroke etiology and abuse of other illicit drugs were ruled out from history and investigations. Neuroimaging studies of the brain revealed infarcts in basal ganglia secondary to occlusion of blood flow in the left anterior and middle cerebral arteries. The mechanism of stroke in this patient was thought to be a cannabis-induced vasculopathy. Many cases of stroke in the young are increasingly being seen in hospitals in resource scarce countries. There seems to be a predilection for the basal ganglia in ischemic stroke following cannabis abuse. Therefore, cannabis abuse should be considered in young adults with basal ganglia infarcts, after excluding other known etiologies.

Prevalence of stroke in three semi-urban communities in middle-belt region of Nigeria: A door to door survey

Introduction The burden of stroke has been projected to increase for developing countries, but data are limited, especially in sub-Saharan Africa. This necessitated this study to determine the stroke prevalence in a semi urban community in middle-belt region of Nigeria. Methods A two-phase door-to-door study was performed in three semi-urban communities of Kwara state; in the first phase 12,992 residents were screened and probable stroke cases were identified by trained health care workers. In the second phase individuals adjudged to be positive for stroke were screened with a stroke-specific questionnaire and made to undergo a complete neurological examination by a neurologist. Stroke diagnosis was based on clinical evaluation using WHO criteria. Results Out of the numbers that were screened, 18 probable stroke cases were identified in the first stage, and of these, 17 fulfilled WHO criteria for stroke, giving a crude prevalence rate of 1.31/1000 population. The prevalence of stroke was higher among the males than the females (1.54/1000 vs. 1.08/1000) with a ratio 1.4: 1. Sixteen subjects (94.1%) had one or more risk factors for stroke. Uncontrolled systemic hypertension (82.4%) was the commonest risk factors for stroke followed by transient ischaemic attack (TIA) (41.2%). Conclusion Stroke is a condition that is prevalent in our environment; especially in older adults and men. Uncontrolled systemic hypertension and previous transient ischaemic attacks were the commonest risk factors for stroke in our community.

Ownership and utilisation of long lasting insecticide treated nets following free distribution campaign in South West Nigeria

Introduction Malaria has proven to be the most horrendous and intractable amongst the health problems confronting countries in the sub-Saharan Africa. This study aims to determine the ownership and utilisation of long lasting insecticide treated nets following free distribution campaign in a state in South West Nigeria. Methods Multi-stage sampling technique was used to recruit 2560 households spread across the 16 LGAs of the state. Interviewer administered standardized questionnaire was used for the survey. Data analysis was done using Stata 10 software. Results Sixty eight point six percent (68.6%) of the households had at least one under-five child living in the household while 32.6% had at least one pregnant woman living in the household. A total of 2440 (95.3%) households received LLIN during the campaign. Overall, the utilization rate for all respondents was 58.5%. Despite the fact that 2440 households received LLINs during the campaign, only 84.3% of them were seen to have hung theirs during the survey. Conclusion Coverage and ownership of LLINs increased significantly following the free distribution campaign. There was a discrepancy between net possession and net use with rate of use lower than possession. Post distribution educational campaign should be incorporated into future distribution campaigns to help increase net utilisation.

Interleukin–6 (IL-6) rs1800796 and cyclin dependent kinase inhibitor (CDKN2A/CDKN2B) rs2383207 are associated with ischemic stroke in indigenous West African Men

BACKGROUND Inherited genetic variations offer a possible explanation for the observed peculiarities of stroke in sub - Saharan African populations. Interleukin-6 polymorphisms have been previously associated with ischemic stroke in some non-African populations. AIM Herein we investigated, for the first time, the association of genetic polymorphisms of IL-6, CDKN2A- CDKN2B and other genes with ischemic stroke among indigenous West African participants in the Stroke Investigative Research and Education Network (SIREN) Study. METHODS Twenty-three previously identified single nucleotide polymorphisms (SNPs) in 14 genes of relevance to the neurobiology of ischemic stroke were investigated. Logistic regression models adjusting for known cardiovascular disease risk factors were constructed to assess the associations of the 23 SNPs in rigorously phenotyped cases (N=429) of ischemic stroke (Men=198; Women=231) and stroke- free (N=483) controls (Men=236; Women=247). RESULTS Interleukin-6 (IL6) rs1800796 (C minor allele; frequency: West Africans=8.6%) was significantly associated with ischemic stroke in men (OR=2.006, 95% CI=[1.065, 3.777], p=0.031) with hypertension in the model but not in women. In addition, rs2383207 in CDKN2A/CDKN2B (minor allele A with frequency: West Africans=1.7%) was also associated with ischemic stroke in men (OR=2.550, 95% CI=[1.027, 6.331], p=0.044) with primary covariates in the model, but not in women. Polymorphisms in other genes did not show significant association with ischemic stroke. CONCLUSION Polymorphisms rs1800796 in IL6 gene and rs2383207 in CDKN2A/CDKN2B gene have significant associations with ischemic stroke in indigenous West African men. CDKN2A/CDKN2B SNP rs2383207 is independently associated with ischemic stroke in indigenous West African men. Further research should focus on the contributions of inflammatory genes and other genetic polymorphisms, as well as the influence of sex on the neurobiology of stroke in people of African ancestry.

Profile and causes of mortality among elderly patients seen in a tertiary care hospital in Nigeria

BACKGROUND Old age is one of the factors associated with increased risk of dying when admitted to hospital. Therefore, aim of this study was to examine causes and pattern of death among elderly patients managed in a tertiary care hospital in Nigeria with scanty mortality records. MATERIALS AND METHODS This prospective study was on deaths that occurred in patients 60 years and above admitted to University of Ilorin Teaching Hospital (UITH), Ilorin, between January 2005 and June 2007. Excluded were all brought-in-dead during the study period. Information obtained included demographic data, duration on admission, and diagnosis. Causes of death were determined from clinical progress notes and diagnosis. RESULTS A total of 1298 deaths occurred during the study period, of which 297 occurred in persons 60 years and above with crude death rate of 22.8%. The mean age at death was 68 ± 9 years (ranged 60-100 years). This consisted of 59% males and 41% females. Mean age at death for females was 69.7 ± 8.7 years and for males 68.1 ± 9.8 years (P = 0.05). Mean values of serum chemistry were sodium 137 ± 8 mMol/l, potassium 3.6 ± 1 mMol/l, urea 11 ± 8 mMol/l, and creatinine 126 ± 91 μmol/l. The value of mean haemogram concentration was 10.5 ± 3 gm/dl and white cell count was 12 ± 2 × 10(9)/mm3. The three most common diagnoses at deaths were stroke (19.8%), sepsis (16.5%), and lower respiratory tract disease (8.1%). Infectious diseases accounted for 38.2% of all diagnoses. Collective mean length of hospital stay (LOS) at death was 6.8 ± 8.6 (ranged 15 minutes-60 days). Close to 27.4% of the deaths occurred within 24 hours and neurological disorder had shortest hospital stay (4.6 ± 6.3 days), followed by endocrine disorders (6.8 ± 8.4 days) and respiratory diseases (8.4 ± 5.6 days) [P = 0.001]. CONCLUSION Hospital mortality is high amongst older people. Stroke and infectious diseases are leading causes of death. Efforts should be geared toward reducing risk for cardiovascular diseases and improvement on level of personal and community hygiene.