A novel cytokine profile associated with cancer metastasis to mediastinal and hilar lymph nodes identified using fine needle aspiration biopsy - A pilot study.

Cancer metastasis to the lymph nodes is indicative of a poor prognosis. An endobronchial ultrasound-guided fine needle aspiration (EBUS-FNA) biopsy is increasingly being used to sample paratracheal lymph nodes for simultaneous cancer diagnosis and staging. In this prospective, single-center study, we collected dedicated EBUS-FNA biopsies from 27 patients with enlarged paratracheal and hilar lymph nodes. Cytokines were assayed using Bio-Plex Pro human cancer biomarker panels (34 cytokines), in a Bio-Rad 200 suspension array system. A mean cytokine value was taken from each subject with more than 1 lymph node station EBUS-FNA biopsies. Malignant and benign histologic diagnoses were established in 16 and 12 patients, respectively. An initial analysis using the Kruskal-Wallis test with Sidak correction for multiple comparisons, showed significant elevation of sVEGFR-1, IL-6, VEGF-A, Angiopoeintin-2, uPA, sHER-2/neu and PLGF in malignant lymph node samples compared to benign samples. The univariate logistic regression analyses revealed that 6 cytokines were significant predictors and 1 cytokine (PLGF) was marginally significant for discrimination between benign and malignant samples. The prediction power of these cytokines as biomarkers were very high according to the area under the ROC curve. Multiple logistic regression for subsets of the seven cytokine combined; provided an almost complete discrimination between benign and malignant samples (AUC=0.989). For screening and diagnostic purposes, we presented the optimal discrimination cut-off for each cytokine: sVEGFR-1 (2124.5pg/mL), IL-6 (40.2pg/mL), VEGF-A (1060.1pg/mL), Angiopoeintin-2 (913.7pg/mL), uPA (248.1pg/mL), sHER-2/neu (5010pg/mL) and PLGF (93.4pg/mL). For the very first time, a novel cytokine profile associated with cancer metastasis to the paratracheal lymph nodes were reported.

Increase in serum creatinine in a patient on continuous peritoneal dialysis: potential mechanisms and management.

A large elevation in serum creatinine (S(Cr)) on an unchanged peritoneal dialysis (PD) schedule is usually caused by a decrease in total creatinine clearance (C(Cr)), but may also reflect an increase in creatinine (Cr) production. A meticulously compliant 43-year-old man with lupus nephritis on automated nocturnal PD plus an additional daytime exchange developed a rise in S(Cr) to 16.73 mg/dL from 8.06 mg/dL after starting fenofibrate, while total C(Cr) decreased only to 61.5 L/1.73 m2 from 77.4 m2 weekly. Creatinine excretion was 16.4 mg/(kg x 24 h) pre-fenofibrate. It increased to a high of 26.2 mg/(kg x 24 h) during the period of fenofibrate intake and returned to 21.9 mg/ (kg x 24 h) 2 months after discontinuation of that drug. The patient's age, weight, height, body mass index, 24-h drain and urine volumes, total Kt/V urea, serum urea nitrogen, urea nitrogen excretion, and (for the pre-fenofibrate period) S(Cr), Cr excretion, estimated Cr production, and measured-to-predicted Cr excretion (using a formula developed in PD patients) were within the 95% confidence intervals (CIs) obtained in a control group of 24 other men on similar PD schedules. The patient's Cr excretion and production were above the 95% CIs of the control group while he was on fenofibrate, and they returned toward or within the 95% CIs after cessation of the drug. The patient's serum creatine phosphokinase was not elevated while he was taking fenofibrate. A thorough investigation of the potential mechanisms of a rise in S(Cr) during the course of PD is warranted to determine if the rise is disproportional to any fall in total C(Cr). In the latter case, Cr excretion and production should be evaluated, and if elevated, conditions potentially causing the rise in Cr production (fenofibrate in this patient) should be sought, and appropriate therapeutic interventions should be implemented.

Sources of variation in estimates of lean body mass by creatinine kinetics and by methods based on body water or body mass index in patients on continuous peritoneal dialysis.

OBJECTIVE: We identified factors that account for differences between lean body mass computed from creatinine kinetics (LBM(cr)) and from either body water (LBM(V)) or body mass index (LBM(BMI)) in patients on continuous peritoneal dialysis (CPD). DESIGN: We compared the LBM(cr) and LBM(V) or LBM(BMI) in hypothetical subjects and actual CPD patients. PATIENTS: We studied 439 CPD patients in Albuquerque, Pittsburgh, and Toronto, with 925 clearance studies. INTERVENTION: Creatinine production was estimated using formulas derived in CPD patients. Body water (V) was estimated from anthropometric formulas. We calculated LBM(BMI) from a formula that estimates body composition based on body mass index. In hypothetical subjects, LBM values were calculated by varying the determinants of body composition (gender, diabetic status, age, weight, and height) one at a time, while the other determinants were kept constant. In actual CPD patients, multiple linear regression and logistic regression were used to identify factors associated with differences in the estimates of LBM (LBM(cr)LBM(V). The differences in determinants of body composition between groups with high versus low LBM(cr) were similar in hypothetical and actual CPD patients. Multivariate analysis in actual CPD patients identified serum creatinine, height, age, gender, weight, and body mass index as predictors of the differences LBM(V)-LBM(cr) and LBM(BMI)-LBM(cr). CONCLUSIONS: Overhydration is not the sole factor accounting for the differences between LBM(cr) and either LBM(V) or LBM(BMI) in CPD patients. These differences also stem from the coefficients assigned to major determinants of body composition by the formulas estimating LBM.

Vitamin D status of seminomadic Fulani men and women.

The purpose of this study was to assess the vitamin D status of Fulani men and women in northern Nigeria. The Fulani are seminomadic pastoralists whose culture, economy, and diet are centered on cattle. Most of the foods consumed by the Fulani are not good sources of vitamin D. Also being Muslim, the women do not derive much benefit from the vitamin D-generating effects of sunlight due to their dress habits. Furthermore, childhood rickets is common in the region. Serum was collected from 22 Fulani men (age, 47.6 +/- 8.3 years; body mass index [BMI], 21.1 +/- 3.2 kg/m2) and 29 women (age, 55.5 +/- 13.5 years; BMI, 21.6 +/- 3.1 kg/m2) in rural northern Nigeria and analyzed for 25-hydroxyvitamin D2 and D3 using ultraperformance liquid chromatography coupled with mass spectrometry Eighty-three percent of the women and 45% of the men had serum 25-hydroxyvitamin D levels in the hypovitaminosis D range (10-30 ng/mL). In the males, there was a strong negative correlation between serum vitamin D and BMI (r = -0.49, p = .022) and percent body fat (r = -0.51, p = .015). No such correlations were observed in the Fulani women. Our main conclusion is that about half the men and most of the women in the Fulani community where this study was conducted are inadequately nourished with respect to vitamin D. A high prevalence of hypovitaminosis D indicates an elevated risk for rickets in children and bone fractures in adults.

Lipid profiles and trans fatty acids in serum phospholipids of semi-nomadic Fulani in northern Nigeria.

The Fulani are semi-nomadic pastoralists of West Africa whose diet, culture, and economy are centred on cattle. Previous studies have shown that the Fulani of northern Nigeria derive 50% of their total calories from fat and 30% of their calories from milk, cheese, yogurt, and butter oil that contain significant amounts of trans fatty acids (TFAs), primarily vaccenic acid, which raise total serum cholesterol and low-density lipoproteincholesterol (LDL-C), and lower high-density lipoprotein-cholesterol (HDL-C). The study was conducted to know how the consumption of relatively large amounts of dairy products by adult Fulani affected the TFA content of their serum phospholipids. Blood samples were collected from 22 male and 29 female Fulani, aged 35-60 years, who were living in rural areas of Gombe state in northeastern Nigeria. The total serum phospholipid fraction was isolated, and its fatty acid composition was determined. Surprisingly, vaccenic acid was not detected, and three other TFAs--18:1-t6, 18:1-t9, and 18:2-t9,t12--together accounted for only 0.16% of the total fatty acid. The mean serum total cholesterol, LDL-C, and triglyceride concentrations of the subjects were within the normal range for populations in developed countries; however, at 32 mg/dL, the mean serum HDL-C concentration of the Fulani males was slightly below the lower limit of the reference range. No correlations were observed between the total TFA percentage or that of the three individual TFAs and any of the parameters of the serum lipid profile. These findings indicate that, with respect to TFAs at least, the fatty acid pattern of the serum phospholipids of Fulani pastoralists does not reflect the high TFA content of their traditional diet. Despite the consumption of rumenic acid-rich dairy products, for unknown reasons, the semi-nomadic Fulani manage to maintain a low level of TFAs in their blood and a relatively healthful serum lipid profile. While the mechanism that accounts for this disconnect between the consumption of TFAs by Fulani pastoralists and the proportion of TFAs in their serum phospholipids is obscure, possibilities include discrimination against rumenic acid during the process of triglyceride synthesis and chylomicron synthesis in the intestine and the preferential oxidation of TFAs by Fulani the people compared to other ethnic groups.

Pulmonary function correlates with body composition in Nigerian children and young adults with sickle cell disease.

Sickle cell disease (SCD) is associated with impaired growth and skeletal maturation. Decreased fat-free mass (FFM) and body fat (BF) have been reported in Nigerian children with SCD relative to healthy age- and gender-matched controls. Pulmonary abnormalities, including reduced forced vital capacity (FVC), forced expiratory volume in one second (FEV(1)) and total lung capacity (TLC), have also been described in children with SCD. Since undernutrition is common in sub-Saharan Africa, we were interested in knowing the relationship between pulmonary function and body composition in Nigerian children and young adults with SCD. Body composition was determined using bioelectrical impedance and pulmonary function was assessed by spirometry in Nigerian children and young adults aged 7-35 years (n = 102) as well as healthy age-and gender-matched controls (n = 104). Age-adjusted data revealed 19-26% lower FFM for male (P < 0.001) and female (P < 0.001) subjects with SCD relative to the controls. FVC, FEV(1) and PEF were also significantly reduced in male and female children and young adults with SCD compared to their control counterparts. For both male and female patients and controls, FVC, FEV(1) and PEF correlated positively with FFM (P < 0.001). PEF for the female subjects with SCD diverged progressively with increasing age relative to the controls and the rate of change was significantly lower (P < 0.001). We conclude that pulmonary function is reduced in Nigerian children and young adults with SCD compared to controls and that for both groups, pulmonary function is directly related to body composition. These findings underscore the need for early nutritional intervention for children with SCD.

Use of calcaneal ultrasound and biochemical markers to assess the density and metabolic state of the bones of adults with hepatic cirrhosis.

Bone loss has been shown to be associated with chronic liver disease (CLD) caused by ethanol consumption or viral infection, and trabecular bone is affected more than cortical bone. We therefore used calcaneal ultrasound to compare the bone status of 54 males and 20 females with CLD in northern Nigeria with 88 age- and gender-matched healthy controls. Serum levels of bone-specific alkaline phosphatase (BSAP) and the N-terminal telopeptide of type-1 collagen (NTx) were also measured to estimate relative rates of bone synthesis and turnover, respectively. The mean stiffness index (SI) of the males with CLD and the male controls were not different; however, the mean SI of the female subjects with CLD was lower than for the female controls (101 vs. 86, p=0.003). The levels of NTx and BSAP were markedly elevated in the males, but not in the females, with CLD. Liver function tests did not correlate with ultrasound parameters or biochemical markers of bone metabolism. These results show that Nigerian women, but not males, with CLD have decreased bone density as assessed by calcaneal ultrasound; however, the high rate of bone turnover in Nigerian males with CLD indicates that they are at risk for bone loss.

Nutritional factors associated with anaemia in pregnant women in northern Nigeria.

This study was conducted to assess the relative contribution of iron, folate, and B 12 deficiency to anaemia in pregnant women in sub-Saharan Africa. In total, 146 pregnant women, who attended two antenatal clinics in Gombe, Nigeria, were recruited into the study. The majority (54%) of the women were in the third trimester. Blood samples were obtained for determination of haematocrit and for measurement of serum iron, total iron-binding capacity, ferritin, folate, vitamin B12, and homocysteine. Malaria was present in 15 (9.4%) women. Based on a haemoglobin value of<105 g/L, 44 (30%) women were classified as anaemic. The major contributing factor to anaemia was iron deficiency based on the serum concentration of ferritin (<10 ng/mL). The mean homocysteine concentration for all subjects was 14.1 pmol/L, and homocysteine concentrations were inversely correlated with concentrations of folate and vitamin B 12. The serum homocysteine increased markedly at serum vitamin B12 levels below 250 pmol/L. The most common cause of anaemia in the pregnant women in northern Nigeria was iron deficiency, and the elevated concentrations of homocysteine were most likely due to both their marginal folate and vitamin B12 status.

Computation of the dose of continuous peritoneal dialysis required for adequate peritoneal urea clearance without taking into account peritoneal transport indices.

To test the feasibility of calculating, in the absence of peritoneal transport studies, the dose (daily drain volume) of continuous peritoneal dialysis (CPD) that will produce a high probability of adequate fractional peritoneal urea clearance (Kpt/Vurea), we randomly separated 619 clearance studies in patients on continuous ambulatory peritoneal dialysis (CAPD) with 4 daily exchanges into a derivation (n = 322) and a validation (n = 297) group. In the derivation group, the dialysate-to-plasma urea concentration ratio (D/Purea) was < or = 0.799 within the lowest 5% of the studies. By the urea clearance formula, a D/Purea value of 0.799 will produce weekly Kpt/Vurea values of 1.70 or better if the ratio of the daily drain volume to plasma water (Dv/V) is > or = 0.304 L/L. Among the 56 studies in the validation group with Dv/V values of 0.304 L/L or more, 52 (92.9%) had weekly Kpt/Vurea values of 1.70 or better. Assuming a suitable (low) D/Purea value for a given CPD treatment, it is possible to derive the dose of dialysis (the Dv/V ratio) that will provide adequate peritoneal urea clearance levels regardless of peritoneal transport characteristics. This method is applicable to the prescription of CPD for patients lacking studies of peritoneal transport. Anuric patients on CAPD with 4 daily exchanges require a Dv/V value of 0.304 L/L or better to have a > or = 0.9 probability of achieving a weekly Kpt/Vurea of 1.70 or better.

Hydration abnormalities in Nigerian patients on chronic hemodialysis.

The state of hydration affects the outcomes of chronic dialysis. Bioelectrical impedance analysis (BIA) provides estimates of body water (V), extracellular volume (ECFV), and fat-free mass (FFM) that allow characterization of hydration. We compared single-frequency BIA measurements before and after 14 hemodialysis sessions in 10 Nigerian patients (6 men, 4 women; 44+/-7 years old) with clinical evaluation (weight removed during dialysis, presence of edema) and with estimates of body water obtained by the Watson, Chertow, and Chumlea anthropometric formulas. Predialysis and postdialysis values of body water did not differ between BIA and anthropometric estimates. However, only the BIA estimate of the change in body water during dialysis (-0.8+/-2.9 L) did not differ from the corresponding change in body weight (-1.3+/-3.0 kg), while anthropometric estimates of the change in body water were significantly lower, approximately one-third of the change in weight. Bioelectrical impedance analysis correctly detected the intradialytic change in body water content (the ratio V/Weight) in 79% of the cases, while anthropometric formula estimates of the same change were erroneous in each case. Compared with patients with clinical postdialysis euvolemia (n=7), those with postdialysis edema (n=5) had higher values of postdialysis BIA ratios V/FFM (0.77+/-0.01 vs. 0.72+/-0.03, p<0.01) and ECFV/V (0.53+/-0.02 vs. 0.47+/-0.06, p<0.05), respectively. Bioelectrical impedance analysis appeared to underestimate body water and extracellular volume in a patient with massive ascites and bilateral pleural effusions. Anthropometric formulas are not appropriate for evaluating the state of hydration in patients on chronic hemodialysis. In contrast, BIA provides estimates of hydration agreeing with clinical estimates in the same patients, although it tends to underestimate body water and extracellular volume in patients with large collections of fluid in central body cavities.

Management of extreme azotemia from urinary tract obstruction without dialysis. Clinical correlates and kinetic modeling of the recovery of renal function.

The recovery of renal function following release of urinary tract obstruction with advanced azotemia determines both the need for emergency dialysis in the early post-obstructive period and the long-term planning for chronic kidney disease management. A man with prostatic cancer who presented with 16 days of anuria and a serum creatinine (Scr) of 42.7 mg/dl but had evidence suggesting residual renal function was managed conservatively and reached a steady-state Scr of 1.6 mg/dl within 84 h of urinary bladder catheterization. Modeling of the decrease in Scr taking into account the decline in the body creatinine pool that existed prior to the release of the obstruction and the accumulation in body fluids of creatinine produced after the release of the obstruction suggested that recovery of the value of glomerular filtration rate corresponding to the steady-state Scr occurred at the release of the urinary obstruction. The case illustrates both the clinical factors that may lead to the decision to postpone dialysis in a patient presenting with extreme obstructive azotemia and a novel method of modeling the recovery of renal function after release of the obstruction.

Trans fatty acids and conjugated linoleic acids in the milk of urban women and nomadic Fulani of northern Nigeria.

BACKGROUND: Trans fatty acids (TFAs) and conjugated linoleic acids (CLAs) are present in dairy products and human milk and can have detrimental and beneficial effects in humans. The content of TFAs and CLAs in milk is determined largely by the diet of the mother. METHODS: We compared the proportions of TFAs and CLAs in the milk of rural Fulani in northern Nigeria who consume dairy products to that of women living in an urban center who consume little in the way of dairy products. Lactating Fulani women (n=41) and women residing in the city of Jos, Nigeria (n=41) were recruited into the study. We predicted that the milk of the Fulani pastoralists would contain higher amounts of TFAs and CLAs compared to their urban counterparts. RESULTS: The mean total TFA proportions for the Fulani and urban women were 0.22% and 0.34%, respectively, and were not significantly different. The percentages of CLAs in milk fat were not different between rural and urban women (0.16% vs 0.14%). These TFA and CLA values were 4- to 10-fold lower than for milk of women elsewhere in the world. CONCLUSIONS: The percentages of TFAs and CLAs in milk were not different between rural and urban dwellers in northern Nigeria whose diets differ greatly in the amounts of dairy products they contain. However, the fact that the percentages of TFAs and CLAs in the milk of Nigerian women were much lower than the percentages reported from other parts of the world may have implications for the long-term growth and development of infants in the northern Nigeria and elsewhere in the Western Sahel.

Effect of Norplant contraceptive on the bones of Nigerian women as assessed by quantitative ultrasound and serum markers of bone turnover.

Levonorgestrel is a commonly used progestin-only contraceptive that is available as subdermal (Norplant) and intrauterine implants. Other progestin-only contraceptives such as injectable medroxyprogeterone acetate have been shown to decrease bone mineral density in long-term users. We used calcaneal ultrasound to compare the bone quality of Nigerian women between 25 and 50 years of age who had Norplant implants for 1-4 years to that of women who were not using any form of hormonal contraceptive. The mean stiffness index of women who had Norplant implants for as long as 4 years was not significantly different from that of controls. However, serum markers of bone turnover were significantly decreased in women with Norplant implants compared to age-matched controls. Serum bone-specific alkaline phosphatase was significantly decreased in subjects with Norplant implants for 1 year (13.7+/-6.0 vs. 23.0 U/L for controls, p = .001) and serum NTx was significantly decreased in subjects with implants for 3 years (10.6+/-4.9 vs. 17.6+/-7.7 bone collagen equivalents per liter for controls, p < .001). We conclude that although levonorgestrel contraceptive decreased overall bone turnover, it had no deleterious effect on the bone quality of women using Norplant implants for up to 4 years.

Lack of precision of indirect estimates of body water affects urea kinetic analysis in chronic peritoneal dialysis.

To test the precision of estimates of body water and urea clearance in peritoneal dialysis (PD), we compared, in 925 PD patients who underwent formal urea kinetics studies, estimates of V and Kt/V urea obtained by the use of the Watson, Hume, and Sahlgrenska anthropometric formulas and two novel formulas, one (Vcreat) computed using fat-free mass (FFM) estimated from creatinine kinetics as 0.73 x FFMcreat, and the other (VBMI) calculated as 0.73 x FFM(BMI) where FFM(BMI) was obtained by the Gallagher formula, which estimates body composition as a function of body mass index (BMI). Comparisons by twos were performed using the paired t-test and the Wilcoxon sign rank test with the Bonferroni correction for multiple (n=10) comparisons. The results for V (liters) were Watson, 36.7 +/- 7.1; Hume, 37.3 +/- 7.3; Sahlgrenska, 36.8 +/- 7.6; Vcreat, 32.2 +/- 9.8; and VBMP 37.2 +/- 7.8. With the exception of V(BMI) and V(Hume) which did not differ, all other values differed (p < 0.001) from one another regardless of whether a parametric or nonparametric comparison was performed. The results for weekly total Kt/V urea were Watson, 2.05 +/- 0.57; Hume, 2.03 +/- 0.57; Sahlgrenska, 2.06 +/- 0.59; from Vcreat 2.42 +/- 0.71; and from V(BMP) 2.03 +/- 0.58. All of those values differed from one another (p < 0.001) by both methods of comparison. Using cut-off values (1.50, 1.75, and 2.00) as indices of adequate total weekly Kt/V urea, the discrepancies between any two estimates by the five studied formulas varied in the range 1.1% - 34.2%. Despite numerically close mean values, estimates of V based on various anthropometric formulas differ substantially and cause substantial discrepancies in the classification of Kt/V urea as inadequate or adequate. This lack of precision, added to the known lack of accuracy of the estimates, confounds the interpretation of the clinical relevance of urea kinetic estimates in PD.

Plasma and urinary free amino acid concentrations in preeclamptic women in northern Nigeria.

BACKGROUND: Preeclampsia/eclampsia is one of the major causes of maternal and fetal mortality in Nigeria and many other countries in sub-Saharan Africa. We determined if serum and urine concentrations of amino acids were abnormal in women with this disorder of pregnancy in Gombe, Nigeria. METHODS: Free amino acids were measured in serum and urine of women (ages, 15 to 40 years) with preeclampsia/eclampsia (n=37) and their pregnant age and gestational age matched controls (n=16). RESULTS: The concentrations of 19 of the 20 serum amino acids that are common in proteins were not significantly different between the control and preeclamptic groups. Phenylalanine was increased in the preeclamptic women compared to the controls (p<0.05); however, the difference between the two values was small (119 vs. 104 umol/l, respectively). The concentrations of urine free amino acids were indexed to urine creatinine (i.e., nmol/mg creatinine). Five amino acids were significantly elevated in the urine of preeclamptic patients vs. the control group: proline (100%, p<0.05), the branched amino acids, valine (80%, p<0.05), leucine (61%, p<0.05), isoleucine (49%, p=0.01), and methionine (52%, p<0.005). On the other hand, the concentrations of a nutritionally non-essential amino acid, glycine (p=0.01), and an essential amino acid, histidine (p=0.01), were both reduced by about one-third in the urine of the preeclamptic women. CONCLUSIONS: Our findings indicate that there are disturbances in urinary amino acid excretion but not in the serum amino acid profile in the preeclamptic patients. The degree of aminoaciduria is probably not sufficient to significantly affect overall nitrogen balance or precipitate a deficiency of one or more of the essential amino acids.

Evaluation of aminoaciduria in severely traumatized patients.

BACKGROUND: It has been documented in the literature that hypocalcemia, hypoaminoacidemia, and hyperaminoaciduria are sequelae of trauma. The aminoaciduria of patients with different types and severity of traumatic injuries was investigated. METHODS: Eight severely traumatized patients (ISS range, 20-43 years) and eight age-, gender-, and weight-matched controls were studied. Plasma and urine were collected 2.5-72 h after admission. Quantification of 28 amino acids in plasma and urine was performed by reversed-phase high-performance liquid chromatography. Urine concentrations of amino acids were indexed to creatinine. RESULTS: The patients' mean serum concentrations of 4 amino acids (arginine, threonine, isoleucine, and glutamine) were significantly decreased, 2 others (tryptophan and glutamic acid) were significantly increased, and 22 were unchanged (p-value< or =0.05). Fractional (urinary) excretion of 11 amino acids was increased in the patients. The patients' serum total calcium and albumin concentrations were decreased, but the mean ionized calcium concentration was not significantly different from the controls. CONCLUSIONS: The results of this study showed that aminoaciduria involving many amino acids is common for patients with different traumatic injuries and that the aminoaciduria is correlated with a reduction of the total serum calcium concentration.

Phase angle correlates with n-3 fatty acids and cholesterol in red cells of Nigerian children with sickle cell disease.

OBJECTIVE: To determine the cholesterol content and fatty acid composition of red cell membrane phospholipids (PL) of children with sickle cell disease (SCD) and to correlate these levels with whole body phase angle that is related to the integrity and function of cell membranes. STUDY DESIGN: Blood samples were obtained from 69 children with SCD and 72 healthy age- and gender-matched controls in Nigeria for the determination of the cholesterol content and proportions of fatty acids in red cell PL. Bioelectrical impedance analysis was used to obtain resistance (R) and reactance (Xc) from which phase angle was calculated as arctan Xc/R. Cholesterol (normalized to lipid phosphorus) and the proportions of individual fatty acids were correlated with phase angle. RESULTS: The proportions of palmitic (p < 0.001), stearic acid (p = 0.003) and cholesterol (p < 0.001) were significantly higher in the red cells of children with SCD, whereas the proportions of arachidonic acid and docosahexaenoic acid were reduced (p = 0.03 and < 0.001, respectively) compared to controls. The phase angle was inversely correlated with the proportions of palmitic acid (p = 0.03) and oleic acid (p < 0.001) and cholesterol (p = 0.003). Three n-3 polyunsaturated fatty acids-eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid- were positively correlated with phase angle (p < 0.001). CONCLUSIONS: The fatty acid composition and cholesterol content of tissue membranes in SCD correlate with the phase shift measured by bioelectrical impedance analysis. Phase angle measurements may provide a non-invasive method for monitoring interventions aimed at altering the lipid composition of membranes.

Pulmonary function of herdsmen.

OBJECTIVE: To determine whether the pulmonary function deficit documented previously in Fulani children is also present in adult Fulani herdsmen in northern Nigeria. SUBJECTS AND METHODS: The subjects for this study consisted of adult Fulani men from the hamlet of Magama Gumau and adult non-Fulani men from the city of Jos. Age, height, weight, mid-arm circumference (MAC), triceps skin-fold thickness, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory flow during the middle half of the FVC maneuver (FEF25-75%), and peak expiratory flow rate (PEF) were measured. Body mass index (BMI) and FEV1/FVC were calculated for all subjects. Multiple regression analysis was performed to identify correlations between pulmonary function parameters and anthropometric variables. RESULTS: The 44 Fulani subjects and 28 urban subjects were well-matched for age and height. The Fulani men weighed significantly less than the urban men (58.5+/-9.4 versus 67.4+/-11.3 kg, p <0.001) and consequently had significantly lower BMI, MAC, and triceps skin-fold thickness. The only significant difference in pulmonary function parameters between the two groups was in FEV1/FVC (0.93+/-0.1 versus 0.85+/-0.1, p <0.001). Small but significant correlations were found between pulmonary function parameters and anthropometric variables for both study populations. CONCLUSIONS: The pulmonary function deficits documented previously in Fulani children and adolescents were not present in adult Fulani men. However, the observed elevation in FEV1/FVC in the rural Fulani men as compared to their urban counterparts, which is often seen in restrictive pulmonary patterns, deserves further study.

Serum lipid profiles and homocysteine levels in adults with stroke or myocardial infarction in the town of Gombe in northern Nigeria.

While the incidence of infectious diseases has been on the decline in developing countries, the toll of cardiovascular diseases, including stroke and myocardial infarction, has been increasing. The impression of physicians in certain regions of the western Sahel, including the state of Gombe in northeastern Nigeria, is that macrovascular disease in the indigenous population is on the rise. This study was, therefore, undertaken to compare well-established risk factors for cardiovascular disease in a group of 53 men (n=34) and women (n=19) in the town of Gombe who had suffered a stroke or heart attack with the corresponding parameters in 48 age- and gender-matched healthy adults living in the same environment. The parameters of cardiovascular diseases considered were: overweight and obesity, blood pressure, lipid profiles, and homocysteine. While the male and female patients who had suffered stroke (n=48) or heart attack (n=5) were borderline hypertensive, their mean body mass index values were not different from the corresponding values of their control groups. Although the serum homocysteine levels of the patients and controls were not significantly different, 85% of the stroke patients had serum homocysteine levels greater than 10 microM. These high homocysteine levels could not be accounted for by sub-optimal folate or vitamin B 12 status. The serum levels of HDL-cholesterol and triglyceride were not significantly different between the male and female patients and their respective controls. However, the males, but not the females, with macrovascular disease had significantly higher levels of total cholesterol (161 vs 137 mg/dL, p=0.04) and LDL-cholesterol (91 vs 70 mg/dL, p=0.02). In addition, both female and male stroke/myocardial infarction patients exhibited an elevated LDL-cholesterol/HDL-cholesterol ratio. These results indicate that blood pressure and the LDL-cholesterol/HDL-cholesterol ratio are associated with stroke and myocardial infarction in adults in northern Nigeria, thereby creating potential opportunities for possible public-health interventions.

Serum lipid profiles and risk of cardiovascular disease in three different male populations in northern Nigeria.

The Fulani of northern Nigeria are indigenous semi-nomadic pastoralists whose diet consists largely of dairy products. Despite their consumption of relatively large amounts of saturated fats, an earlier study showed that their total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and serum triglyceride levels fall within the reference range of values for North Americans. Men in the cities of Jos and Abuja, two populations who also reside in northern Nigeria, differ from the Fulani with regard to diet and activity level. Males in both Jos and Abuja have diets consisting of high protein or carbohydrate and are more sedentary than the Fulani subjects. The main aims of the study were to measure the concentrations of various lipids in the blood serum of male urban dwellers in Jos and Abuja and to compare their blood lipid profiles with those of the rural Fulani (mean age 33.9 years). Blood serum samples from 118 men in Jos (mean age 37.9 years) and 77 men in Abuja (mean age 34.4 years) were analyzed for total cholesterol, triglycerides, LDL, HDL, homocysteine, folate, and vitamin B12. In addition to height and weight, systolic and diastolic blood pressures were measured. The mean total cholesterol, triglyceride, HDL and LDL values for the three groups of subjects fell within or close to the accepted range of values for North Americans. However, the Fulani males had HDL values (mean, 33.9 mg/dL) below the range of values prescribed for North Americans (>40 mg/dL). Moreover, the Fulani men and the men in Abuja had a total cholesterol/ HDL ratio of 4.2 and 4.0 respectively, which exceed the accepted value (< or =3.5) prescribed by the Columbia University. In all three populations, the incidence ofhomocysteinaemia (serum homocysteine > 12.4 micromol/L) was very high. Their mean homocysteine levels ranged from 14.7 to 16.7 pmol/L and could not be accounted for by folate or vitamin B12 status. The mean blood pressures of the Abuja (127/77 mm Hg) and the Fulani (120/74 mm Hg) men were within the normotensive range (<130/85 mm Hg). However, the mean blood pressures of the Jos males (131/85 mm Hg) indicated borderline hypertension. These data indicate that, with regard to serum lipids, urban and rural adult Nigerian males have generally favourable risk factors for cardiovascular disease when compared with healthy North Americans. All three sub-populations, however, have levels of homocysteine that are cause for concern vis-à-vis their overall health status.