Progress with the implementation of kangaroo mother care in four regions in Ghana.

AIM: To measure progress with the implementation of kangaroo mother care (KMC) for low birth-weight (LBW) infants at a health systems level. DESIGN: Action research design, with district and regional hospitals as the unit of analysis. SETTING: Four regions in Ghana, identified by the Ghana Health Service and UNICEF. PARTICIPANTS: Health workers and officials, health care facilities and districts in the four regions. INTERVENTION: A one-year implementation programme with three phases: (1) introduction to KMC, skills development in KMC practice and the management of implementation; (2) advanced skills development for regional steering committee members; and (3) an assessment of progress at the end of the intervention. MAIN OUTCOME MEASURES: Description of practices, services and facilities for KMC and the identification of strengths and challenges. RESULTS: Twenty-six of 38 hospitals (68%) demonstrated sufficient progress with KMC implementation. Half of the hospitals had designated a special ward for KMC. 66% of hospitals used a special record for infants receiving KMC. Two of the main challenges were lack of support for mothers who had to remain with their LBW infants in hospital and no follow-up review services for LBW infants in 39% of hospitals. CONCLUSIONS: It was possible to roll out KMC in Ghana, but further support for the regions is needed to maintain the momentum. Lessons learned from this project could inform further scale-up of KMC and other projects in Ghana.

Habitual physical activity differentially affects acute and short-term energy intake regulation in young and older adults.

BACKGROUND: Energy intake (EI) regulation is impaired in older adults, but it is not known if habitual physical activity affects accuracy of EI regulation in older compared with young adults. OBJECTIVE: We hypothesized that the ability to compensate for a high-energy yogurt preload beverage at a subsequent ad libitum meal (i.e. acute compensation) and over the course of the testing day (i.e. short-term compensation) would decrease with age, but the magnitude of the decline would be smaller in physically active compared with sedentary older adults. DESIGN: On two occasions, young active (n=15), young sedentary (n=14), older active (n=14) and older sedentary (n=11) subjects consumed either a high-energy yogurt preload beverage (YP: 500 ml, 1988 kJ, men; 375 ml, 1507 kJ, women), or no preload (NP), 30 min before an ad libitum test meal. EI at both ad libitum meals was measured, and total daily EI was determined on both testing days. Percent EI compensation for the YP was calculated for the test meal and testing day to determine acute and short-term compensation. RESULTS: Percent EI compensation at the test meal was significantly lower in the older compared with the young subjects (65+/-4 vs 81+/-4%, P=0.005). There was no effect of habitual physical activity level on acute compensation, and no age by physical activity level interaction (P=0.60). In contrast, short-term compensation was not different with age (87+/-5 vs 93+/-6%, older vs young, P=0.45), but was more accurate in active vs sedentary subjects (100+/-5 vs 79+/-6%, P=0.01). As with acute compensation, there was no age by physical activity interaction (P=0.39). CONCLUSION: Acute EI regulation is impaired in older adults, which is not attenuated by physical activity status. However, EI regulation over the course of a day is more accurate in active vs sedentary adults, which may facilitate long-term energy balance. Future work is needed to determine if higher energy expenditure in older active vs older sedentary adults improves long-term EI regulation.

Late benefits 10-18 years after drug therapy for infection with Schistosoma haematobium in Kwale District, Coast Province, Kenya.

Late benefits of remote antischistosomal therapy were estimated among long-term residents of an area with high transmission of Schistosoma haematobium (Msambweni, Kenya) by comparing infection and disease prevalence in two local adult cohorts. We compared 132 formerly treated adults (given treatment in childhood or adolescence > or = 10 years previously) compared with 132 age- and sex-matched adults from the same villages who had not received prior treatment. The prevalence of current infection, hematuria, and ultrasound bladder abnormalities were significantly lower among the previously treated group, who were found to be free of severe bladder disease. Nevertheless, heavy infection was equally prevalent (2-3%) in both study groups, and present rates of hydronephrosis were not significantly different. Therapy given in childhood or adolescence appears to improve risk for some but not all manifestations of S. haematobium infection in later adult life. Future prospective studies of continued treatment into adulthood will better define means to obtain optimal, community-based control of S. haematobium-related disease in high-risk locations.

Increased ratio of tumor necrosis factor-alpha to interleukin-10 production is associated with Schistosoma haematobium-induced urinary-tract morbidity.

Bladder and kidney disease, which affect approximately 25%-30% of subjects infected with Schistosoma haematobium, are mediated by T cell-dependent granulomatous responses to schistosome eggs. To determine why only some infected subjects develop disease, we examined the hypothesis that infected Kenyan subjects with ultrasound-detected urinary-tract morbidity (n=49) had dysregulated cytokine production leading to enhanced granulomatous responses, compared with subjects of similar age and intensity of infection without morbidity (n=100). Peripheral blood mononuclear cells from subjects with morbidity produced 8-fold greater levels of egg antigen-driven tumor necrosis factor (TNF)-alpha and had a 99-fold greater mean TNF-alpha:interleukin (IL)-10 ratio, compared with subjects without disease. No differences in cytokine response to non-egg-derived schistosome antigens were observed between groups. Subjects with morbidity had increased TNF-alpha production in response to endotoxin, suggesting an innate hyperresponsiveness. These results indicate that increased TNF-alpha production, relative to that of IL-10, is associated with developing bladder-wall morbidity with S. haematobium infection.

Mitochondrial DNA control region sequences from Nairobi (Kenya): inferring phylogenetic parameters for the establishment of a forensic database.

Large forensic mtDNA databases which adhere to strict guidelines for generation and maintenance, are not available for many populations outside of the United States and western Europe. We have established a high quality mtDNA control region sequence database for urban Nairobi as both a reference database for forensic investigations, and as a tool to examine the genetic variation of Kenyan sequences in the context of known African variation. The Nairobi sequences exhibited high variation and a low random match probability, indicating utility for forensic testing. Haplogroup identification and frequencies were compared with those reported from other published studies on African, or African-origin populations from Mozambique, Sierra Leone, and the United States, and suggest significant differences in the mtDNA compositions of the various populations. The quality of the sequence data in our study was investigated and supported using phylogenetic measures. Our data demonstrate the diversity and distinctiveness of African populations, and underline the importance of establishing additional forensic mtDNA databases of indigenous African populations.

Low heritable component of risk for infection intensity and infection-associated disease in urinary schistosomiasis among Wadigo village populations in Coast Province, Kenya.

To estimate their heritable component of risk for Schistosoma haematobium infection intensity and disease, we performed a community-based family study among an endemic population in coastal Kenya. Demography and family linkages were defined by house-to-house interviews, and infection prevalence and disease severity were assessed by standard parasitologic testing and by ultrasound. The total population was 4,408 among 912 households, with 241 identified pedigree-household groups. Although age- and sex-adjusted risk for greater infection intensity was clustered within households (odds ratio = 2.7), analysis of extended pedigree-household groups indicated a relatively low heritability score for this trait (h2 = 0.199), particularly after adjustment for common household exposure effects (adjusted h2 = 0.086). Statistical evidence was slightly stronger (h2 = 0.353) for familial clustering of bladder morbidity, with an adjusted h2 = 0.142 after accounting for household exposure factors. We conclude that among long-established populations of coastal Kenya, heritable variation in host susceptibility is low, and likely plays a minimal role in determining individual risk for infection or disease.

Large-scale, polymerase chain reaction-based surveillance of Schistosoma haematobium DNA in snails from transmission sites in coastal Kenya: a new tool for studying the dynamics of snail infection.

Levels of prepatent Schistosoma haematobium infection were monitored in intermediate host snails (Bulinus nasutus) collected from transmission sites in coastal Kenya, using a polymerase chain reaction (PCR) assay amplifying the Dra I repeated sequence of S. haematobium. The timing and number of prepatent and patent infections were determined for each site and, where the time of first appearance was clear, the minimal prepatent period was estimated to be five weeks. High, persistent, prepatency rates (range = 28-54%), indicated a significant degree of repeated area contamination with parasite ova. In contrast, rates of cercarial shedding proved locally variable, and were either low (range = 0.14-3.4%) or altogether absent, indicating that only a small proportion of infected snails reach the stage of cercarial shedding. Given the apparently strong focal effects of environmental conditions, implications of these new data are discussed regarding the estimation of local force of transmission and the design of control activities.

Randomized comparison of low-dose versus standard-dose praziquantel therapy in treatment of urinary tract morbidity due to Schistosoma haema tobium infection.

At present, anthelmintic therapy with praziquantel at a dose of 40 mg/kg of body weight is the recommended treatment for control of urinary tract morbidity caused by Schistosoma haematobium. Although this standard regimen is effective, drug cost may represent a significant barrier to implementation of large-scale schistosomiasis control programs in developing areas. Previous comparison trials have established that low-dose (20-30 mg/kg) praziquantel regimens can effectively suppress the intensity of S. haematobium infection in endemic settings. However, the efficacy of these low-dose regimens in controlling infection-related morbidity has not been determined in a randomized field trial. The present random allocation study examined the relative efficacy of a 20 mg/kg dose versus a 40 mg/kg dose of praziquantel in control of hematuria and bladder and renal abnormalities associated with S. haematobium infection in an endemic area of Coast Province, Kenya. After a nine-month observation period, the results indicated an advantage to the standard 40 mg/kg praziquantel dose in terms of reduction of infection prevalence and hematuria after therapy (P < 0.01 and P < 0.005, respectively). However, the two treatment groups were equally effective in reducing structural urinary tract morbidity detected on ultrasound examination. We conclude that in certain settings, a 20 mg/kg dose of praziquantel may be sufficient in providing control of morbidity due to urinary schistosomiasis in population-based treatment programs.

Water absorption characteristics of dental composites incorporating hydroxyapatite filler.

Water uptake characteristics of BisGMA-based composites incorporating untreated and surface-treated hydroxyapatite (HA) with a silane coupling agent have been investigated. The water absorption and desorption behaviour of these composites obeyed the classical diffusion theory. The diffusion coefficients of the composites during first absorption were very similar to that for the base resin, suggesting that the water uptake process occur mainly in the resin matrix. The incorporation of HA reduced the water uptake of the base resin and lower uptake was found for those formulated with surface-treated HA. It was also observed that the equilibrium uptake decreased with increasing filler loading. However, the filled specimens had a higher water absorption than which would be expected on the basis of the resin content. This increase in the water uptake was largely due to the presence of porosity and filler particle aggregates in the microstructure of composites, although the adsorption of some water onto the filler surface has not been ruled out. The experimental composites showed higher solubilities than that obtained for the base resin.

Regulation of macronutrient balance in healthy young and older men.

OBJECTIVE: To determine the influence of age on the ability to adjust macronutrient oxidation to changes in diet composition. Our hypothesis was that the ability to adjust macronutrient oxidation to changes in diet composition would be impaired with age. DESIGN: Cross-sectional, randomized to three different isocaloric diets containing a constant percentage protein but varying in percentage fat and percentage carbohydrate: mixed diet (M; 15/30/55); high-fat diet (HF; 15/60/25), and high-carbohydrate (HC; 15/15/70). SUBJECTS: Six young (YM; age=25+/-1 y) and five middle-aged and older men (OM; age=63+/-3 y). MEASUREMENTS: Each subject underwent 24 h whole-room calorimetry on day 4 of each diet to determine 24 h macronutrient oxidation rates. Macronutrient balance was calculated from the individual macronutrient oxidation rates and the corresponding macronutrient intake. RESULTS: Body mass, percentage fat, and fat-free mass were similar in the two groups. Twenty-four-hour energy expenditure (EE) and energy balance did not differ across diets or between groups; 24 h EE was approximately 7% lower (NS) in the OM. Macronutrient oxidation rates were not significantly different in YM vs OM during M. Protein oxidation was similar across diets, but higher (P<0.05) in OM. Fat oxidation contributed 28.8+/-7.0% vs 37.8+/-4.7% to 24 h EE on M (NS) in the OM vs YM, respectively. This increased to 58.4+/-6.7 vs 51.9+/-5.3% of 24 h EE (NS) in the OM vs YM, respectively, during HF and decreased to 25.4+/-9.7 vs 20.2+/-14.3% (NS) during HC (diet effect, both P<0.05). Carbohydrate oxidation contributed 54.3+/-10.5% vs 56.6+/-2.4% of 24 h EE (NS) on M in the OM vs YM, respectively. This decreased to 19.5+/-10.6 vs 29.9+/-12.6% (NS) during HF and increased to 53.6+/-12.3 vs 64.7+/-14.3% (NS) in the OM vs YM, respectively during HC (diet effect, P<0.05). CONCLUSION: Taken together, these results suggest that the ability to adjust macronutrient oxidation to changes in diet composition is maintained in OM and, thus, is unlikely to contribute to the increased susceptibility to weight gain and obesity development that accompanies aging.

Gender difference in cardiovagal baroreflex gain in humans.

We tested the hypothesis that women would demonstrate lower cardiovagal baroreflex gain compared with men. If so, we further hypothesized that the lower cardiovagal baroreflex gain in women would be associated with their lower aerobic fitness and higher body fat percentage compared with men. To accomplish this, we measured cardiovagal baroreflex gain (modified Oxford technique) in sedentary, nonobese (body mass index < 25 kg/m2) men (age = 26.0 +/- 2.1 yr, n = 11) and women (age = 26.9 +/- 1.6 yr, n = 14). Resting R-R interval and diastolic blood pressure were similar in the two groups, but systolic blood pressure was lower (P < 0.05) in the women. Cardiovagal baroreflex gain was significantly lower in the women compared with the men (13.3 +/- 1.5 vs. 20.0 +/- 2.8 ms/mmHg, P < 0.05). The lower cardiovagal baroreflex gain in the women was not related (P > 0.05) to their lower aerobic fitness and was only marginally related to their higher body fat percentage (r = -0.34, P < 0.05). There were no gender differences in the threshold and saturation, operating range, or operating point (all P > 0.05), although the operating point fell significantly to left (i.e., at a lower systolic blood pressure) compared with men. Therefore, the findings of this study suggest that the gain of the cardiovagal baroreflex is reduced whereas other parameters were similar in women compared with men. The mechanisms responsible for the reduced cardiovagal baroreflex gain remain unclear.

Blood pressure reductions with exercise and sodium restriction in postmenopausal women with elevated systolic pressure: role of arterial stiffness.

OBJECTIVES: This study determined the relative efficacy of aerobic exercise (daily walking) and moderate dietary sodium restriction (sodium intake <100 mmol/day) for reducing systolic blood pressure (SBP) and pulse pressure (PP) in postmenopausal women with elevated initial levels, and the potential role of reductions in large artery stiffness in these changes. BACKGROUND: Lifestyle behaviors are recommended for lowering blood pressure (BP) in adults with elevated baseline levels, but there is little information as to the relative efficacy of different interventions or the mechanisms underlying their potential beneficial effects. METHODS: After baseline measurements and random assignment, 35 nonmedicated healthy postmenopausal women with SBP between 130 and 159 mm Hg completed three months of either aerobic (walking) exercise (n = 18; 62 +/- 9 years, mean +/- SD) or moderate dietary sodium restriction (SR) (n = 17; 65 +/- 10 years, mean +/- SD). RESULTS: Body mass and composition, plasma volume, and fasting concentrations of metabolic coronary risk factors did not differ between the groups at baseline or change with intervention. Systolic BP and PP at rest decreased with both exercise and SR (p < 0.05); however, the reductions were three- to fourfold greater with SR (p < 0.05). Sodium restriction, but not exercise, also reduced 24-h SBP and PP (p < 0.05). Aortic pulse wave velocity (PWV) and carotid augmentation index were reduced only with SR (p < 0.05). Changes in SBP and PP at rest and over 24 h correlated with the corresponding changes in aortic PWV (r = 0.53 to 0.61, p < 0.01). CONCLUSIONS: Moderate SR lowers SBP and PP in postmenopausal women with elevated baseline levels more than does daily walking. The greater blood pressure reductions with SR may be mediated in part by a decrease in the stiffness of the large elastic arteries.

Hydroxyapatite as a filler for dental composite materials: mechanical properties and in vitro bioactivity of composites.

Hydroxyapatite (HAp) powder was treated with gamma-methacryloxypropyltrimethoxy-silane (gamma-MPS) using standard techniques in both non-polar and polar systems. Infrared spectra (DRIFT) and thermogravimetric analysis (TGA) confirmed the presence of gamma-MPS on the surface of the HAp filler particles. Series of experimental composites consisting of bisphenol-a-glycidyl methacrylate (BisGMA) based resin and untreated or treated HAp filler were produced to determine the mechanical properties and in vitro bioactivity. The incorporation of HAp filler into the BisGMA base resin had an enhancing effect on the flexural strength and Young's modulus of the base resin, the latter being increased by a factor of three. The mechanical properties of the filled resin were not affected by the surface treatment of the HAp, but filler loading was found to have a significant effect on Young's modulus. Higher proportions of silane-treated HAp of smaller particle size could be incorporated in the monomer phase giving rise to composites of higher stiffness. Examination of the fracture surfaces showed that the silanized HAp particles maintained better contact with the polymer matrix. In vitro study revealed that the composites incorporating silanized HAp formed a compact and continuous calcium phosphate layer on their surface after 4 weeks immersion in a simulated body fluid (SBF).

Total blood volume in endurance-trained postmenopausal females: relation to exercise mode and maximal aerobic capacity.

We have recently shown that postmenopausal female distance runners demonstrate elevated levels of blood volume compared with sedentary healthy peers. We also found a strong positive relation between blood volume and maximal oxygen consumption. In young adult males, endurance exercise training increases blood volume when performed in the upright, but not in the supine body position. Based on these observations, we hypothesized that among postmenopausal females, the elevation in blood volume would be absent or attenuated in women who train in the horizontal vs. upright body position, and that the lower blood volume in the former would be associated with lower maximal aerobic capacity. Thus, we measured supine resting plasma and total blood volumes (Evans blue dye) and maximal oxygen consumption in postmenopausal women: 10 sedentary controls, 10 swimmers and 10 runners matched for age (60 +/- 2; 59 +/- 2; 58 +/- 2 years, mean +/- SE) and hormone replacement use (5 per group). The swimmers and runners were further matched for training volume (4.5 +/- 0.2 vs. 4.8 +/- 0.6 h week-1), relative performance (78 +/- 5 vs. 75 +/- 3% of age-group world record) and fat-free mass (45.5 +/- 0. 8 vs. 44.9 +/- 1.5 kg). Total blood volume and maximal oxygen consumption were highest in the runners (81.2 +/- 4; 52.4 +/- 3 mL kg-1, respectively) and progressively lower in the swimmers (68.8 +/- 3; 44.2 +/- 2) and controls (59.2 +/- 2; 37.9 +/- 2; all P < 0. 05). In the pooled population, blood volume was positively related to maximal oxygen consumption (r = 0.72, P < 0.0001). We conclude that in endurance-trained postmenopausal females matched for training volume and competitive performance: (1) blood volume is lower in those who train in the horizontal (swimmers) compared with the upright position (runners); (2) the lower blood volume is associated with a lower maximal aerobic capacity. Nevertheless, blood volume and maximal oxygen consumption are higher in postmenopausal women who train in the horizontal position than in sedentary controls.

Influence of gender on the sympathetic neural adjustments to alterations in systemic oxygen levels in humans.

The purpose of this investigation was to determine whether gender influences the muscle sympathetic nerve activity (MSA) and systemic cardiovascular adjustments to alterations in systemic oxygen levels. To accomplish this, we performed direct (intraneural) measurements of muscle sympathetic nerve activity in 11 male and seven female young healthy adults during room air breathing, moderate isocapnic hypoxaemia and hyperoxaemia. During hypoxaemia, arterial oxygen saturation declined similarly in men and women. The magnitudes of the peak increases in MSA and stimulus-response 'gain' were not different between groups. However, the women had a shorter latency of response (P < 0.05). Women also demonstrated a greater increase in heart rate and a modest elevation in diastolic blood pressure, whereas the ventilatory responses were identical in the two groups. During normoxic recovery, MSA returned to baseline more quickly in women than in men (P < 0.05). During hyperoxaemia, muscle sympathetic nerve activity decreased only in the men (P < 0.05). Heart rate decreased slightly (P < 0.05) in both men and women, whereas blood pressure and minute ventilation were unchanged from normoxic control levels. Our findings fail to support an effect of gender on the peak muscle sympathetic nerve activity response to moderate isocapnic hypoxaemia in healthy young adult humans, although women demonstrate a shorter latency for sympathoexcitation and recovery under these conditions. In response to hyperoxaemia, women fail to demonstrate the sympathoinhibition consistently observed in men, possibly because of the low resting levels of MSA characteristic of young adult women. Thus, gender appears to contribute to the interindividual variability in sympathetic and cardiovascular responses to alterations in systemic oxygen levels.

Cardiopulmonary baroreflex inhibition of sympathetic nerve activity is preserved with age in healthy humans.

1. We tested the hypothesis that the ability of the cardiopulmonary baroreflex to produce sympathoinhibition is reduced with age in humans. Eleven young (23 +/- 1 years, mean +/- s.e.m.) and ten older (64 +/- 1) healthy adult males were studied under supine conditions (control) and in response to cardiopulmonary baroreflex stimulation evoked by acute central circulatory hypervolaemia (10 deg head-down tilt). The two groups were normotensive and free of overt cardiovascular disease. 2. Supine baseline (control) levels of efferent muscle sympathetic nerve activity (MSNA) burst frequency were twice as high in the older men (41 +/- 2 vs. 21 +/- 2 bursts min-1, P < 0.05). In both groups in response to head-down tilt arterial blood pressure and heart rate were unchanged, peripheral venous pressure (PVP) increased (P < 0.05), MSNA total activity decreased (P < 0.05), antecubital venous plasma noradrenaline concentrations did not change significantly, and forearm blood flow and vascular conductance increased (vascular resistance decreased) (all P < 0.05). The mean absolute DeltaMSNA/DeltaPVP was similar in the young and older men, although the higher control levels of MSNA in the older men resulted in a smaller percentage DeltaMSNA/DeltaPVP (P < 0.05). Per DeltaPVP, the reduction in forearm vascular resistance was smaller in the older men, but there were no age group differences when expressed as increases in forearm vascular conductance. 3. These results indicate that the ability of the cardiopulmonary baroreflex to inhibit MSNA is well preserved with age in healthy adult humans. As such, these findings are not consistent with the concept that this mechanism plays a role in the age-associated elevation in basal MSNA.

Water sorption behaviour of polymeric systems based on tetrahydrofurfuryl methacrylate.

Earlier research has described the water absorption behaviour, drug release and biological properties of a room temperature polymerizing system based on poly(ethyl methacrylate) (PEM) powder and tetrahydrofurfuryl methacrylate (THFM) monomer. This work has been extended, with respect to water sorption behaviour, by replacing the monomer to various extents with hydroxyethyl methacrylate (HEMA), and poly(ethyl methacrylate) by ethyl methacrylate (EM)-THFM copolymers. Replacing the THFM with HEMA, and gelling with PEM, increased the diffusion coefficient progressively. The replacement of PEM by EM-THFM copolymers, when gelled with THFM monomer, substantially reduced equilibrium water uptake, and increased diffusion coefficients. However, with HEMA monomer, equilibrium uptake was unaffected, but the diffusion coefficient decreased with increasing THFM content of the copolymer. This is due to a complex interaction of THFM cross-linking the copolymer, and the effect of EM on the water uptake. Heat polymerizing the PEM-THFM system reduced equilibrium uptake and the diffusion coefficient, compared with the room temperature polymerizing system; this could reflect molecular weight differences.