Prevalence and pattern of abnormal glucose tolerance in adult Nigerians with primary hypertension.

BACKGROUND: Hypertension and diabetes mellitus relate to one another aetiologically and prognostically. Studies show that hypertension occurs frequently in diabetics than non-diabetics. Data on the prevalence of abnormal glucose tolerance in hypertensive Nigerians are scanty This study assesses the magnitude of this problem in adult Nigerians with primary hypertension. METHOD: Oral glucose tolerance test was performed on 124 adult Nigerians (64 hypertensives, 60 normotensives) to determine the prevalence of abnormal glucose tolerance. Body mass index and waist circumference were measured. Plasma glucose was analyzed by the glucose oxidase method. RESULTS: The hypertensive (32 males, 32 females) and normotensive (30 males, 30 females) had mean ages of 47.6 +/- 10.1 years and 44.2 +/- 7.6 years. The mean body mass index and waist circumference of hypertensives and normotensives were 30.2 +/- 80 kg/m, 100.8 +/- 17.2 cm and 28.5 kg/m, 88.5 +/- 14.1 cm. The mean plasma glucose in mmols/l, during oral glucose tolerance test of hypertensives and normotensives, at 0 hr, 1 hr and 2 hrs were, 4.79 +/- 0.99, 6.94 +/- 1.5, 5.96 +/- 1.82 and 4.42 +/- 0.90, 6.25 +/- 1.02, 5.05+ +/- 1.8 respectively. The response to glucose load was significantly higher in the hypertensives than normotensives particularly at 2 hours p < 0.001. 62.5% of hypertensives responded normally to glucose load. 32.8% had impaired glucose tolerance. All controls responded normally. 6.25% of hypertensives had impaired fasting glucose. 4.6% of hypertensives had diabetes. No control had diabetes. The hypertensives with abnormal glucose tolerance had higher body mass index and waist circumference, than hypertensives with normal glucose tolerance, and controls. CONCLUSION: Mean venous plasma glucose levels are higher in hypertensive adult Nigerians, than their normotensive counterparts. Impaired glucose tolerance is more prevalent than impaired fasting glucose and diabetes mellitus.

Lipid profiles of apparently healthy adolescents in Calabar, Nigeria.

OBJECTIVE: To determine the lipid profiles of adolescents in Calabar, Nigeria. DESIGN: A cross sectional prospective study. SETTING: The study was carried out in Calabar, a city located on the south-eastern axis of Nigeria. Calabar is rapidly acquiring the status of a tourism destination in the country and as such the lifestyles of the city dwellers are changing rapidly. SUBJECTS: The subjects were apparently healthy students 10 to 18 years old attending day secondary schools in the city. A structured questionnaire was used to collect demographic and anthropometric data from the students. Blood samples were collected from 375 adolescents and used for analyzing their lipid profiles. MAIN OUTCOME MEASURES: Abnormal levels of serum lipids. RESULTS: The results showed that only one subject (0.3%) had an abnormally high total cholesterol (TC) level and 33% of the subjects had low levels of high density lipoprotein cholesterol (HDL-C). Borderline high levels of total cholesterol, low density lipoprotein cholesterol (LDL-C) and triglycerides (TG) were found in 2.4%, 3.2% and 5.1% of subjects respectively. CONCLUSION: This study shows that the lipid profiles of Nigerians are low but gradually rising towards values seen in places where coronary heart disease occurs in epidemic proportions. This may point to an increased risk ofarteriosclerosis in future generations.

Evaluation of thyroid function in diabetes mellitus in Calabar, Nigeria.

The prevalence of abnormal thyroid hormone levels in diabetes mellitus in Nigeria is not well described. To determine the incidence of abnormal thyroid hormone levels in diabetics in Calabar, Nigeria, fasting blood samples from 161 diabetic subjects and 105 non-diabetic controls were analysed. Free thyroxine (FT), thyroid stimulating hormone (TSH), total triiodothyronine (T(3)) and total thyroxine (T(4)) kits obtained from Biomerica Inc. of USA were used for the analysis. TSH levels (1.80±1.62) in diabetics were significantly lower (p=0.016) than the level in non-diabetic controls (2.34±1.24). Male diabetics had lower (p<0.05) levels of TSH (1.192±0.68 miu/ml) than diabetic females (1.90±1.70 mlu/mt). The level of T(3) in diabetic males (125±97ng/ml) was higher than the level in females (98±75ng/dl). TSH (F=2.74, p=0.049), T(4)(F=56.87, p=0.001), T(3)(F=56.44, P=0.001) in diabetics and FT(4) (F=5.74, p=0.002) in controls showed significant variation with the ages of the subjects. Out of 161 diabetics subjects studies 26.6% had low plasma thyroid hormone levels (FT(4)>2.01 ng/dl). This study has shown a high incidence (46.5%) of abnormal thyroid hormone levels among the diabetics in Nigeria (hypothyroidism 26.6%, hyperthyroidism, 19.9%). The prevalence of hypothyroidism was higher in women (16.8%) than in men (9.9%), while hyperthyroidism was higher in males (11%) than in females (8%). This study has defined thyroid function status of diabetics in Calabar, Nigeria probably the first of such work in Africa.

Prevalence and Pattern of Abnormal Glucose Tolerance in Adult Nigerians with Primary Hypertension

Background: Hypertension and diabetes mellitus relate to one another aetiologically and prognostically. Studies show that hypertension occurs frequently in diabetics than non-diabetics. Data on the prevalence of abnormal glucose tolerance in hypertensive Nigerians are scanty. This study assesses the magnitude of this problem in adult Nigerians with primary hypertension. Method: Oral glucose tolerance test was performed on 124 adult Nigerians (64hypertensives; 60normotensives) to determine the prevalence of abnormal glucose tolerance. Body mass index and waist circumference were measured. Plasma glucose was analyzed by the glucose oxidase method. Results: The hypertensive(32 males;32females) and normotensive (30males; 30females) had mean ages of 47.6+/-10.1years and 44.2+/-7.6years.The mean body mass index and waist circumference of hypertensives and normotensives were 30.2+/-80kg/m;100.8+/-17.2cm and28.5kg/m;88.5+/-14.1cm. The mean plasma glucose in mmols/l; during oral glucose tolerance test of hypertensives and normotensives; at 0hr; 1hr and 2hrs were;4.79+/-0.99;6.94+/-1.5;5.96+/-1.82 and4.42+/-0.90;6.25+/-1.02;5.05++/-1.8 respectively. The response to glucose load was significantly higher in the hypertensives than normotensives particularly at 2hours p

Prevalence and Pattern of Abnormal Glucose Tolerance in Adult Nigerians with Primary Hypertension

Background: Hypertension and diabetes mellitus relate to one another aetiologically and prognostically. Studies show that hypertension occurs frequently in diabetics than non-diabetics. Data on the prevalence of abnormal glucose tolerance in hypertensive Nigerians are scanty. This study assesses the magnitude of this problem in adult Nigerians with primary hypertension. Method: Oral glucose tolerance test was performed on 124 adult Nigerians (64hypertensives; 60normotensives) to determine the prevalence of abnormal glucose tolerance. Body mass index and waist circumference were measured. Plasma glucose was analyzed by the glucose oxidase method. Results: The hypertensive(32 males;32females) and normotensive (30males; 30females) had mean ages of 47.6+/-10.1years and 44.2+/-7.6years.The mean body mass index and waist circumference of hypertensives and normotensives were 30.2+/-80kg/m;100.8+/-17.2cm and28.5kg/m;88.5+/-14.1cm. The mean plasma glucose in mmols/l; during oral glucose tolerance test of hypertensives and normotensives; at 0hr; 1hr and 2hrs were;4.79+/-0.99;6.94+/-1.5;5.96+/-1.82 and4.42+/-0.90;6.25+/-1.02;5.05++/-1.8 respectively. The response to glucose load was significantly higher in the hypertensives than normotensives particularly at 2hours p

Rat serum electrolytes, lipid profile and cardiovascular activity onNauclea latifolia leaf extract administration.

Aqueous extract of the leaf and root ofNauclea latifolia Sm. (Rubiaceae) is used in Nigerian folk medicine for the treatment of hypertension. This work is carried out to investigate the effect ofNauclea latifolia leaf extract on lipid profile and cardiovascular activity of rats. Normal and 10% coconut oil fed rats were treated with the water-soluble fraction of the ethanol extract ofNauclea latifolia leaf for 2 weeks. Forty-eight mature male albino rats of the Wistar strain were divided into two experiments of four groups, each group having 6 animals. Experiment I animals were treated with the water-soluble fraction of the ethanol extract whilst experiment II animals were fed 10% coconut oil meal before treatment with the water-soluble fraction of the ethanol extract. A single oral dose ofNauclea latifolia was 170, 340 and 510 mg/kg body wt/day of the extracts respectively for 2 wks. There was no significant change in the lipid profile of the experimental animals as compared with the controls. There was about 40% relaxation on contracted thoracic aorta that was pre-contracted with 2 µM phenylephrine. The viability of the tissue was tested against 10 µM of acetylcholine. There was no significant (P>0.05) change in Na(+) concentration in the serum. However, the K(+) concentration in the serum of the experimental animals showed a significant increase. The study shows that ethanol extract ofNauclea latifolia has vasodilator action on the aorta and that lipid profiles of experimental rats were not affected. Furthermore, the increase in the K(+) may be contributing to the vasodilator effect ofNauclea latifolia.

Methaemoglobin profile in malaria infected children in Calabar.

BACKGROUND: Malaria infection interferes with haemoglobin by disruption of red blood cells and by conversion of haemoglobin to methaemoglobin. This study was to determine the relationship between malaria and the concentration of methaemoglobin using malaria patients. METHODS: Severe malaria-infected children of ages 11 months to 15 years recruited from the children emergency room of University of Calabar Teaching Hospital (UCTH) were used for the study while 62 age--sex matched apparently healthy school children and children that visited the child welfare clinic of UCTH were screened and used as controls. Malaria detection and identifications using WHO procedure were employed. Methaemoglobin (Met Hb) levels were determined using the method of Evelyn and Malloy. RESULTS: The mean MetHb value for malaria-infected children was higher (3.2 +/- 0.8%) than that of the non- malaria infected subjects (1.5 +/- 0.5%). The difference was significant (p < 0.001). Patients with severe malaria parasitaemia had markedly raised MetHb values of 4.0 +/- 0.9% as compared to the values for mild/moderate infected cases (2.9 +/- 0.6%). The difference was statistically significant (p < 0.001). CONCLUSION: This study has demonstrated high level of MetHb value in subjects with severe malaria parasitaemia. It's role in the symptomatology and complications of malaria infection, especially in malaria anaemia should be examined in details. Routine estimation of MetHb in malaria patients is suggested.

Hypofibronectinaemia and severity of sickle cell anaemia in Nigeria.

Plasma fibronectin levels in sickle cell anaemia and apparently healthy Nigerians were investigated to determine any correlation with disease severity. A cheaper in-house plasma fibronectin assay was also developed that could be adapted for use in Africa and elsewhere. Plasma fibronectin assay was concurrently carried out using the newly developed inhibition enzyme-linked immunosorbent assay (ELISA) and a commercial competitive binding ELISA. The in-house assay compared favourably with that of the commercial kit. The mean plasma fibronectin levels in sickle cell anaemia subjects were significantly lower than that of control subjects (P < 0.001). Plasma fibronectin concentration could therefore be useful in assessing the severity of sickle cell anaemia.

Haemoglobin C gene in south eastern Nigeria.

Haemoglobin C (Hb C) is very rare in eastern Nigeria (east of River Niger). Isolated cases have been reported. The incidence is however as high as 6% in western Nigeria. This study was undertaken to locate the isolated cases with a view to determining their origin. Hb electrophoresis was performed on 4,263 subjects in Akwa Ibom State in south eastern region of Nigeria. The subjects were selected from all the local government areas of the state and were aged 15 years and above. They comprised secondary school children, civil servants, farmers and fishermen. The results revealed complete absence of Hb C from the upland population whereas this was present in the fishing settlement population (6 or 0.4% Hb AC and one or 0.07% Hb SC subjects). The possible entry points of Hb C gene into south eastern Nigeria is discussed.

Serum cholesterol profile of some Nigerian pregnant women.

A semi-longitudinal study of the cholesterol profiles at various stages of pregnancy was conducted. The study involved 49 pregnant women who showed no physical signs of obesity, were neither hypertensive nor diabetic, and had a mean age of 24.7 +/- 4.5 (mean +/- SD). The results showed a progressive increase in the serum total and high-density lipoprotein (HDL) cholesterol levels from 4.02 +/- 0.39 mmol/L (mean +/- SD) and 1.81 +/- 0.15 mmol/L, respectively, at 3 months, to 5.59 +/- 0.51 mmol/L and 2.46 +/- 0.18 mmol/ in the ninth month of pregnancy. These represent a 39 +/- 11% and a 35 +/- 10% increase in total and HDL cholesterol, respectively, over the 3-month level. The levels of total and HDL cholesterol however decreased to 4.08 +/- 0.40 mmol/L and 1.89 +/- 0.17 mmol/L, respectively, a month after delivery. The most significant (P < 0.05) month to month increase was recorded between the 6th and the 7th month for both total and HDL cholesterol. The proportion of HDL cholesterol remained fairly constant at 43 +/- 3 to 45 +/- 4% throughout the period of pregnancy covered, and one month after delivery. This suggests a proportional increase in all lipoprotein fractions. It is concluded that the observed changes are normal physiological events.

Distribution of sialic acid between sialoglycoproteins and other membrane components of different erythrocyte phenotypes.

The sialic acid content of erythrocytes of three different AB0 blood groups have been studied. The sialic acid contents of erythrocyte membranes containing 300 mg protein were determined and compared. Groups 0 (Rhesus negative), AB (both Rhesus negative and positive), and B (Rhesus negative) blood differed significantly (p less than 0.05) in total sialic acid content and in the distribution of sialic acid between sialoglycoproteins and other membrane components. Membrane materials containing 300 mg total protein showed sialic acid contents of 52.73 +/- 2.2 mumol sialic acid for group 0 (Rhesus negative) 34.77 +/- 1.16 mumol for group AB (Rh negative), 32.88 +/- 1.52 mumol for AB (Rh positive) and 21.23 +/- 0.84 mumol for B (Rh negative). In group 0 (Rh. neg.) membranes 39.4 +/- 1.4% of the total sialic acid was associated with the sialoglycoproteins. The percentage of sialic acids associated with sialoglycoproteins in other erythrocyte membranes were 77.7 +/- 1.3% for group B, and 55.6 +/- 1.0% and 56.4 +/- 1.8% for group AB (Rh. negative) and (Rh. positive) respectively. The changes appear to be independent of the Rhesus grouping but dependent on the AB0 grouping since membranes of the two Rhesus types of group AB had identical total sialic acid and sialoglycoproteins sialic acids. The sialic acid densities in sialoglycoproteins also differed from one erythrocyte type to another. Group 0 (Rh. negative) membrane sialoglycoproteins had sialic acid density of 140.5 +/- 3.1 nmol/mg compared to 71.7 +/- 1.2 nmol/mg for group B and 128.1 +/- 2.2 and 124.5 +/- 4.0 nmol/mg for group AB Rhesus negative and Rhesus positive respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Proteolysis of sialoglycoprotein by Pasteurella haemolytica cytotoxic culture supernatant.

Proteolytic enzyme activity releasing sialo glycopeptides from 3H-labeled human erythrocyte ghosts was detected in cytotoxic (leukotoxic) culture supernatants from 9 of 12 Pasteurella haemolytica serotypes. Microcrystalline cellulose thin-layer chromatograms of radioactive water-soluble products showed the following two radioactive peaks: a high-mobility minor peak (Rf, 0.54 to 0.74), identified as sialic acid, and a low-mobility major peak (Rf, 0.18 to 0.21), partially characterized as a trichloroacetic acid-soluble, sialic acid-rich fragment with a molecular weight of greater than 3,500, not extractable by chloroform. The sialic acid content of this fragment after treatment with Clostridium perfringens neuraminidase was estimated to be 7.2 X 10(-2) mumol mg-1. The presence of neuraminidase as a separate activity in some culture supernatants was confirmed. It is considered to be responsible for the observed release of free sialic acid. Preliminary studies with the crude enzyme showed that it has a broad pH optimum around pH 7.0 and that activity is not affected by inhibitors of trypsin, chymotrypsin, thermolysin, thio and serine enzymes, nor by an inhibitor of neuraminidase, 2,3-dehydro-2-deoxy-N-acetylneuraminic acid. Activity was, however, inhibited by o-phenanthroline at a high concentration after prolonged treatment. The enzyme hydrolyzed glycophorin at a rate four times higher than the rate for casein. Free glycophorin inhibited the enzyme-induced release of radioactive products from 3H-labeled ghosts. It is speculated that the novel enzyme is a neutral protease, probably metal-dependent, with specificity for sialoglycopeptides. The possible relationship of this protease to the previously reported host species-specific leukotoxicity of P. haemolytica and its potential role in virulence is discussed.