Effect of Obesity on Resistin Concentrations in Normal, Pre-Obese and Obese Apparently Healthy Nigerian-Africans.

BACKGROUND: Among Caucasians, conflicting findings exist on resistin in obesity and its relation to metabolic indices, with scarcity of such in Nigerian-Africans. Therefore, the study assessed plasma resistin and explored its relationship with obesity and selected cardiometabolic risks. METHODS: A cross-sectional comparative-analytical study on 87 randomly-selected non-diabetic Nigerians allocated into three groups by the WHO criteria: 24 normal; 23 pre-obese and 40 obese. Resistin was measured via enzyme-linked immunosorbent assay. One-way Analysis of Variance (ANOVA) and Independent Kruskal-Wallis test determined differences in BMI categories. Spearman's correlation and Multivariate Logistic Regression assessed relationships. A sub-group analysis excluding subjects with first time incidental finding of high blood pressure, determined further associations. RESULTS: Resistin concentrations trended towards higher levels in obese than normal controls {Mean ± SD, 6.72 ± 4.25 ng/mL versus 5.10 ± 2.58 ng/mL}, with significantly (p<0.05) higher obesity indices, fasting insulin (FI) and HOMA-IR in obese than normal controls. Hyperresistinaemia involved 8(9.2%) subjects as against 79(90.8%) with normoresistinaemia, {Mean ± SD, 15.1 ± 2.6 ng/mL versus 5.3 ± 2.8 ng/mL, (p<0.001)}. Log (Ln10) hyperresistinaemia was significantly (p<0.05) positively correlated to obesity indices (BMI, r=0.29, p=0.006; WC, r=0.23, p=0.04) but not to HOMA-IR, FI, FBG, SBP, DBP and age. Ln10 Hyperresistinaemia in females was significantly (p=0.05, OR: 1.12, 95% CI, 1.0-1.25) associated with central obesity by the IDF criteria in both unadjusted and step-wise age, sex, SBP & DBP adjusted models. Similar finding was for generalized obesity, albeit with low odds in all subjects (p=0.009), with persistence in the step-wise age, sex and SBP/DBP adjusted models. In the sub-group analysis, resistin showed similar findings to that of the whole sample population. CONCLUSION: Resistin concentrations trended towards higher levels in obese than normal healthy non-diabetic Nigerian-Africans. Its lack of correlation with HOMA-IR and mild correlations/marginal relations to obesity indices may suggest possible interplay of other proinflammatory cytokines or hormones which may be evaluated in further studies.

CONTEXTE: Chez les Caucasiens, il existe des résultats contradictoires sur la résistine dans l'obésité et sa relation aux indices métaboliques avec la rareté de telles chez les Nigérians-Africains. Par conséquent, l'étude a évalué la résistine plasmatique et a exploré sa relation avec l'obésité et certains risques cardiométaboliques. MÉTHODES: Une étude transversale comparative et analytique a été réalisée sur 87 nigérians non-diabétiques sélectionnés au hasard et répartis en trois groups selon les critères de l'OMS : 24 normaux ; 23 préobèses et 40 obèses. La résistine a été mesurée par dosage immuno-enzymatique. Analyse de variance à sens unique (ANOVA) et test indépendant de Kruskal-Wallis ont déterminé les différences entre les catégories d'IMC. La corrélation de Spearman et la régression logistique multivariée ont évalué les relations. Une analyse de sous-groupe excluant les sujets chez qui une hypertension artérielle avait été découverte par hasard pour la première fois a déterminé d'autres associations. RÉSULTATS: Les concentrations de résistine tendent à être plus élevées chez les sujets obèses que chez les témoins normaux {Moyenne ± SD, 6,72 ± 4,25 ng/mL contre 5,10 ± 2,58 ng/mL}, avec des indices d'obésité significativement (p<0,05) plus élevés, l'insuline à jeun (IF) et l'HOMAIR chez les obèses que chez les témoins normaux. L'hyperrésistinémie concernait 8 (9,2%) sujets contre 79 (90,8%) avec normorésistinémie, {Moyenne ± SD, 15,1 ± 2,6 ng/mL contre 5,3 ± 2,8 ng/mL, (p<0,001)}. L'hyperrésistinémie log (Ln10) était significativement (p<0,05) corrélée positivement aux indices d'obésité (IMC, r=0,29, p=0,006 ; tour de taille, r=0,23, p=0,04) mais pas à HOMA-IR, FI, FBG, SBP, DBP et l'âge. Ln10 L'hyperrésistinémie chez les femmes était significativement (p=0,05, OR : 1,12, IC 95 %, 1,0-1,25) associée à une obésité l'obésité centrale selon les critères de la FID, à la fois de manière non ajustée et par paliers. l'âge, le sexe, la TAS et la TAD. Une constatation similaire a été faite pour l'obésité généralisée, bien qu'avec une faible probabilité chez tous les sujets (p=0,009), avec une persistance dans les modèles ajustés par étape en fonction de l'âge, du sexe et du SBP/DBP. lDans l'analyse de sous-groupe, la résistine a montré des résultats similaires à ceux de l'ensemble de la population de l'échantillon. CONCLUSION: Les concentrations de résistine tendent vers des niveaux plus élevés chez les Nigérians-Africains obèses que chez les Nigérians non-diabétiques en bonne santé. Son manque de corrélation avec HOMA-IR et des corrélations légères/marginales avec les indices d'obésité aux indices d'obésité peut suggérer une interaction possible avec d'autres cytokines ou hormones pro-inflammatoires, ce qui pourrait être évalué dans des études ultérieures. Mots clés: Résistine, obésité, surpoids, non-obésité, non-diabète, Africains Nigérians en bonne santé, risques cardiométaboliques.

RAST-specific IgE to egg and milk in Nigerian asthmatic patients.

Food allergens have been described in studies in southern parts of Nigeria but rarely in northern parts of Nigeria. Furthermore, the role of specific antibody to such allergen moieties have not been determined. The aim of this study is to assess the role of two common food items in the aetiology of asthma in Zaria. RAST-specific IgE to milk and egg, which are two common foods in Nigeria, and skin prick tests were therefore studied in bronchial asthma patients and controls in Ahmadu Bello University Teaching Hospital, Zaria to determine their significance in the clinical manifestation of asthma patients. Total serum IgA, IgE and secretory IgA were also measured in patients and controls. RAST titres were poorly discriminating between controls and patients, although six patients had history of gastrointestinal symptoms after ingestion of egg while three patients had history of such symptoms, some with positive skin prick tests and high RAST-specific IgE titres. Asthmatic patients had significantly higher mean serum secretory IgA and total IgA levels than controls while total serum IgE levels were similarly distributed among patients and controls. It is suggested that provocation tests are mandatory to confirm bronchial allergic reactions to egg and milk and perhaps other food allergens in Nigerians in view of the non-discriminant RAST titres obtained in this study.

RAST-specific IgE to egg and milk in Nigerian asthmatic patients

Food allergens have been described in studies in southern parts of Nigeria but rarely in northern parts of Nigeria. Furthermore; the role of specific antibody to such allergen moieties have not been determined. The aim of this study is to assess the role of two common food items in the aetiology of asthma in Zaria. RAST-specific IgE to milk and egg; which are two common foods in Nigeria; and skin prick tests were therefore studied in bronchial asthma patients and controls in Ahmadu Bello University Teaching Hospital; Zaria to determine their significance in the clinical manifestation of asthma patients. Total serum IgA; IgE and secretory IgA were also measured in patients and controls. RAST titres were poorly discriminating between controls and patients; although six patients had history of gastrointestinal symptoms after ingestion of egg while three patients had history of such symptoms; some with positive skin prick tests and high RAST-specific IgE titres. Asthmatic patients had significantly higher mean serum secretory IgA and total IgA levels than controls while total serum IgE levels were similarly distributed among patients and controls. It is suggested that provocation tests are mandatory to confirm bronchial allergic reactions to egg and milk and perhaps other food allergens in Nigerians in view of the non-discriminant RAST titres obtained in this study

Plasma insulin response to oral glucose tolerance test in type-2 Nigerian diabetics.

OBJECTIVE: To study the plasma insulin pattern in type 2 diabetic Nigerians both in the fasting state and in response to a standard oral glucose tolerance test. DESIGN: A cross sectional study. SETTING: Diabetic clinic, Ahmadu Bello University Teaching Hospital, Zaria Nigeria. SUBJECTS: Forty type 2 diabetic patients and thirty six healthy age and sex matched control subjects was undertaken. INTERVENTIONS: Eligible patients and control subjects underwent a standard oral glucose tolerance test (OGTT). Plasma levels of glucose and insulin levels determined by a glucose oxidase method and ELISA techniques respectively. Student's t-test was used to compare continuous variables, Chi-square test for categorical variable and Pearson's correlation coefficient to define correlation between variables. The level of statistical significance in each case was taken as P < 0.05. RESULTS: Type 2 diabetic patients demonstrated significantly lower fasting plasma insulin levels, when compared to control subjects (4.20+/-1.78 micro- units/ml vs 5.72+/-2.16 micro - units/ml respectively p<0.05). Similarly, plasma insulin levels following oral glucose challenge were significantly lower in the type 2 diabetic population. CONCLUSION: Type 2 diabetic patients in this study demonstrate both fasting post OGTT hypoinsulinaemia. These findings are discussed in the light of the available knowledge on the aetiopathogenesis of type-2 diabetes mellitus in Africans.

Sildenafil citrate (Viagra) for the treatment of erectile dysfunction in Nigerian men.

Fifty-eight Nigerian outpatients with documented erectile dysfunction (ED) received open-label sildenafil citrate (Viagra) for 8 weeks. The 50-mg starting dose could be adjusted to 100 or 25 mg based on response and tolerability. The International Index of Erectile Function (IIEF) Questionnaire, a global efficacy question, and intercourse data recorded in a patient event log were used to assess efficacy. Frequency of penetration and maintained erection were both significantly enhanced (P<0.0001); 95% of patients reported improved erections and 81% of all attempts at intercourse were successful. Orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction also improved significantly (P&<0.0001). The most frequent adverse events (all-cause) were headache (17%) and myalgia (3%); only one patient discontinued treatment because of headache, which was considered unrelated to sildenafil. Oral sildenafil significantly improved erectile function and was well tolerated in this trial of Nigerian men suffering from ED. Our results are consistent with reports from other countries.

CD4+ and CD8+ lymphocytes and clinical features of HIV seropositive Nigerians on presentation.

Eighty of 200 HIV seropositive patients admitted in the medical wards of Ahmadu Bello University Teaching Hospital, Zaria from year 1995 to 1997 were studied on presentation and compared to 40 age and sex matched controls. The main clinical features observed included weight loss, pyrexia, diarrhoea, lymphadenopathy, anaemia and pruritic dermatosis. Sixty-two of the 80 patients (73.2%) presented at stages 3 and 4 of WHO Clinical and Laboratory staging. Thirty (30) percent of these patients died between a period of one to four months after presentation. The main diseases complicating HIV infection at presentation of the 80 patients were Mycobacterium tuberculosis infection (30%), acute bacterial infections (with Salmonella typhi, Streptococcus pneumoniae and Staphylococcus aureus) (24%), candidiasis (14%) and Kaposi sarcoma (2%). Seropositivity for HIV types was found to be HIV-I alone in 43.5% of cases; HIV-II alone in 14% and both HIV-I and II in 42% of cases. Risk factors associated with HIV infection were multiple sexual partners (73%), sexually transmitted disease (70%), and unscreened blood transfusion (1%). HIV positive patients had a mean CD4+ T-cells of 0.24 x 10(9) +/- 0.17 which was significantly lower than the mean of 0.6 +/- 0. 17 x 10(9)/L for controls (P < 0.05 students t-test). Thirty (35%) of the patients had CD4+ counts of less than 0.2 x 10(9)/L (200 cells/microl) at presentation. The mean CD3+ lymphocytes count was 0.51 +/- 0.24 x 10(9)/L for patients and 1.04 +/- 0.71 x 10(9)/L for controls. The mean CD8+ lymphocyte count in patients was 0.29 +/- 0.19 x 10(9)/L and 0.44 x 10(9)/L for controls. Both CD3+ and CD8+ lymphocyte populations were statistically lower in patients than controls (P < 0.05).

T-lymphocyte subsets in patients with hookworm infection in Zaria, Nigeria.

Peripheral lymphocyte subsets CD3, CD4, CD8 were studied using monoclonal antibodies to determine the mechanism of immunosuppression observed in an earlier study with total T-cells using the sheep erythrocyte rosetting technique. The study was carried out in 37 Nigerian patients with hookworm infection (Necator americanus and Ancylostoma duodenale and 17 healthy Nigerians as controls. The leucocyte migration inhibition (LMI) test was also carried out to assess the functional integrity of the lymphocytes, while the hookworm status of the patients was assessed by the Stoll technique for measuring egg counts. The results of the T-cell studied showed that CD3 and CD4 cell percentages were significantly depressed in hookworm patients compared to controls (P<0.05). The difference between mean CD8 percentages and absolutes in hookworms patients and controls were not significant. Absolute CD3 and CD4 numbers were not significantly lowered compared to controls in the study and CD4/CD8 ratios were insignificantly reduced. Patients with polyparasitism including hookworm infection showed significant reduction in CD3 and CD4 cells when compared with controls and with patients with hookworm infection alone. The leucocyte migration inhibition response to purified protein derivative of M. tuberculosis (PPD) was significantly decreased in hookworm patients compared to controls, confirming that functionally cell mediated immunity is depressed in hookworm infection.

Snake bite in Nigeria.

Four families of venomous snakes are found in Nigeria--Viperidae, Elapidae, Colubridae and Actraspididae but three species carpet viper (Echis ocellatus), black-necked spitting cobra (Naja nigricollis) and puff adder (Bitis arietans), belonging to the first two families, are the most important snakes associated with envenoming in Nigeria. The incidence of bites has been reported as 497 per 100,000 population per year with a 12 percent natural mortality, with Echis ocellatus accounting for at least 66 percent in certain foci. Bites occur more often while victims were farming, herding or walking although the spitting cobra may bite victims who roll upon it in their sleep. Carpet viper venom contains a prothrombin activating procoagulant, haemorrhagin and cytolytic fractions which cause haemorrhage, incoagulable blood, shock and local reactions/ necrosis. The spitting cobra bite manifests with local tissue reaction and occassionally with bleeding from the site of bite, but no classic neurotoxic feature has been observed except following Egyptian cobra (N. haje) bites. Cardiotoxicity and renal failure may occassionally occur following bites by the carpet viper and the puff adder. In the laboratory, haematological and other features are noted and immunodiagnosis has a role in species identification. Immobilisation of the bitten limb is probably the single most important first aid measure. Antivenom should be used cautiously when indicated. As only 8.5 percent of snake bite victims attend hospitals in Nigeria, health education should be the main preventive measure, mean-while, the study of immunisation of occupationally predisposed individuals in endemic areas should be intensified. A new Fab fragment antivenom specific to Nigerian Echis ocellatus was investigated clinically, just as the local herbs-Aristolochia spp, Guiera spp and Schummaniophyton spp are investigated experimentally.

Secretory IgA and complement levels in patients with hookworm infection in Zaria.

As a continuing investigation into the immunological reactions involved in hookworm infection the levels of secretory IgA (sIgA). IgM, IgA, complement C3 and C4 were studied in 57 Nigerians with hookworm infection and compared with those of 28 healthy, normal controls. The hookworm patients were divided into three groups based on the degree of anaemia (Hb1-7 and hypochromia +++). Group II had moderate anaemia (Hb8-11, hypochromia ++ and Group III had no signs of anaemia despite the underlying hookworm infection. The patients also comprised those in whom hookworm was the sole infection and those with hookworm associated with other parasites. Significant differences in the results between each patient subgroup and the controls were analysed using the student t-test. IgA was significantly elevated in patients with anaemia of mild to moderate severity and in patients with hookworm only (P < 0.05) while sIgA was significantly elevated in all subgroups compared to controls (P < 0.05). IgM was significantly elevated in-patients with marked anaemia, in-patients without anaemia and in those with hookworm infection associated with other parasites (P < 0.05). The difference in IgG levels between patients and controls was not significant (P 0.1). C4 was significantly elevated in patients with marked moderate anaemia and those with hookworm only (P < 0.05) while C3 levels were not significantly different in the subgroups compared with controls. These results suggest the possibility of polyclonal B-cell activation by T-independent antigens such as the polysaccharide cuticular antigens of the hookworms and the stimulation of the classical pathway of the complement system.

Fleroxacin vs Ciprofloxacin in the Management of Typhoid Fever: A Randomised, Open, Comparative Study in Nigerian Patients.

OBJECTIVE: The antibacterial efficacy of fleroxacin was compared with that of ciprofloxacin in 72 adult Nigerian patients with typhoid fever. PATIENTS AND METHODS: On inclusion into the study, patients were randomised to treatment with either fleroxacin 400mg once daily for 7 days or ciprofloxacin 500mg twice daily for 14 days. Clinical evaluations were performed on days 0, 1, 2, 3, 5 and 7 or 14, and 2 weeks after treatment. Bacteriology was performed on days 0, 3, 7 or 14, and 21 or 28. Laboratory tolerability parameters were monitored for all patients as well as incidence of adverse events. RESULTS: Bacteriological response on day 3 was 93.5 and 64.0% for fleroxacin and ciprofloxacin, respectively. At term and follow-up there was bacteriological cure in 97.0% of patients with fleroxacin and 100% with ciprofloxacin. The clinical cure was 100% for both groups at term. The incidence of adverse events was 5.4% with fleroxacin and 2.8% with ciprofloxacin. CONCLUSION: The results demonstrated that while the clinical response rate with both drugs was comparable, fleroxacin exhibited a faster bacteriological clearance rate. We therefore concluded that 7 days' therapy with fleroxacin 400mg once daily was as effective as 14 days' therapy with ciprofloxacin 500mg given twice daily in the management of typhoid fever in Nigerian patients. It was also observed that the quinolones possessed greater potential and benefits as first-line therapy for the management of typhoid fever in this environment. The tolerability profile was good for both treatment regimens.

Polymorph function and cellular immunity in Nigerians with pulmonary tuberculosis.

Polymorphonuclear leukocyte intracellular killing of Staphylococcus aureus and chemotactic indices as well as T and B lymphocyte subpopulations were determined in 35 healthy controls and 70 Nigerians with pulmonary tuberculosis. The patients were radiologically classified into exudative, fibro-cavitary, miliary, and mixed lesions groups. Migration inhibition factor (MIF) production and glucose-6-phosphate dehydrogenase (G-6 PD) levels were also determined in 40 patients and 20 controls. The polymorph function as shown by chemotaxic and killing index was significantly reduced (P < 0.05) in all patients when compared to the controls. Reduced G-6-PD levels though found in patients when compared to the controls was not significant. A reversal of the T helper/T suppressor ratio was found in all tuberculosis patients when compared to the controls as a result of decreased T helper cell numbers. T helper cells as well as the MIF index tended to be lowest in the miliary lesions group.

Pregnancy associated alpha-glycoprotein (SP-III) in Nigerian pregnant women.

Pregnancy associated protein (SP-III) was measured by rocket electroimmunoassay in the sera of Nigerian women with normal and abnormal singleton pregnancy. A tendency to increases of SP-III levels with advancing gestational age was observed. SP-III may contribute to immunosuppression in preventing anti-allograft responsiveness and levels may also reflect the effect of infections since SP-III is also leucocyte derived. Values in PET and anaemia in pregnancy were similar to values in normal pregnant women.

Immunosuppression in Nigerians with hookworm infection.

T rosette cells results in patients with (Necator americanus and Ancylostoma duodenale) hookworm infection, divided into groups on the basis of the degree of anaemia (Group I had marked anaemia Hb 1-7, hypochromia ), Group II had moderate anaemia (Hb 8-11, hypochromia ++) and Group III had no signs of anaemia despite the underlying hookworm infection), were compared with results in 28 healthy controls who had no signs of other infection and excreting no ova of hookworm or other parasites. The level of sheep erythrocyte rosette-forming T-lymphocytes (SE-TL) in the patients (Group I:42 +/- 8%; Group II:45 +/- 11%; Group III:47 +/- 6%) was markedly reduced compared to controls (58 +/- 13%) (P < 0.001). The leucocyte migratory responses to purified protein derivative (P.P.D); were significantly (P < 0.05) reduced in all the subgroups as compared with the controls. The results support the hypothesis of the existence of immunosuppression in patients with hookworm infection.

Haptoglobin subtypes among four different populations.

Haptoglobin subtypes were analysed by isoelectric focusing in four populations from Colombia, England, Nigeria, and India. There is a wide range of variation of allele frequencies in these four populations: HP*1S = 15-28%, HP*1F = 5-19%, HP*2FS = 54-79%. With the exception of the English, and the Spanish-speaking population of Colombia, all interpopulation comparisons showed significant heterogeneity. There is an extreme variation for the HP*1F allele in different populations, and a possible geographical cline of the HP*2FS allele increasing from west to east. The data presented here suggest that HP subtypes provide a useful anthropogenetic marker for racial differentiation.

Anti-thrombin III deficiency in Nigerian children with sickle cell disease. Possible role in the cerebral syndrome.

A prospective study of Nigerian children with sickle cell disease was undertaken to determine serum levels of antithrombin III (AT-III) and compare these with normal controls. Mean serum AT-III was significantly lower in patients than in controls (14.51 +/- 4.84 mg/dl and 17.75 +/- 5.92 mg/dl) respectively. Seven of the 49 sickle cell patients had AT-III levels below 50% of normal values. Mean platelet counts were significantly higher in sicklers than in normal controls. AT-III deficiency may predispose to thrombotic complications in children with sickle cell disease.

Population variation in molecular polymorphisms of the short arm of the human X chromosome.

Five DNA probes (RC8, 754, XJ 1-1, pert 87.8, and L1.28) from the short arm of the human X chromosome were investigated in samples from five populations (English, Nigerian, Chinese, Muslim, and Hindu from India). The variation in the allele frequencies of several probes between different groups was significant. The average heterozygosity in females of the five populations ranged from 32% to 51%. The genetic distance between the five groups was compatible with that using traditional polymorphic systems. There is an interesting suggestion of longitudinal cline for allele *2 (9 kb) detected with probe L1.28. The X-linked RFLPs are useful genetic markers for anthropological studies.

Serotype variation in vibrio cholerae el tor diarrhoea in northern Nigeria.

Serotyping of Vibrio cholerae organisms causing epidemics in Zaria and environs since 1975 to 1986 shows that Hikojima serotype was prevalent from 1976-1978, but Ogawa became prevalent from 1984 till 1986. The internal and external pressures responsible for these selections are unclear.

Renal function in non-insulin dependent--diabetes mellitus.

Creatinine clearance, urinary specific gravity after water deprivation and fractional excretion of sodium, potassium and phosphate were measured in 28 patients with uncomplicated non-insulin dependent diabetes mellitus. Defective concentrating capacity was found in 46pc of the patients and 21pc had decreased glomerular filtration rate. Renal handling of sodium was normal in the patients but they showed a tendency for renal retention of potassium. Glycosuric patients showed marked phosphaturia.

Felty's syndrome in a Nigerian.

The first case of Felty's syndrome to be reported in a Nigerian, a fifty five-year-old woman who developed splenomegaly and leukopenia during the course of strongly seropositive rheumatoid arthritis of ten years duration is presented. her arthritis had lasted for about ten years, but she did not have the severe deforming disease known to be associated with Felty's syndrome. Radiologically there were no erosions and subcutaneous nodules were absent. She had a positive granulocyte specific anti-nuclear factor, cryoglobulins containing IgA and IgM and her polymorph-nuclear granulocytes showed evidence of impaired killing of staphylococci.