Cytokine responses to Plasmodium falciparum liver-stage antigen 1 vary in rainy and dry seasons in highland Kenya

Seasonal epidemics of malaria occur in highland areas of western Kenya where transmission intensity varies according to rainfall. This study describes the seasonal changes in cytokine responses to Plasmodium falciparum liver-stage antigen 1 (LSA-1) by children (< or =17 years old) and adults (> or =18 years old) living in such a highland area. Fourteen- to 24-mer peptides corresponding to the N- and C-terminal nonrepeat regions of LSA-1 stimulated production of interleukin-5 (IL-5), interleukin-10 (IL-10), gamma interferon (IFN-gamma), and tumor necrosis factor alpha (TNF-alpha) by peripheral blood mononuclear cells (PBMC) from 17 to 73% of individuals in both age groups in both seasons. IL-10 and TNF-alpha responses were more frequent during the high-transmission, rainy season than during the low-transmission, dry season (73 and 67% versus 17 and 25% response rates, respectively). In contrast, there was no seasonal change in the proportion of LSA-1-driven IFN-gamma and IL-5 responses. Children produced less IFN-gamma than adults, but IL-5, IL-10, and TNF-alpha levels were similar for both age groups. Depletion of CD8(+) cells from PBMC decreased IFN-gamma but increased IL-10 production. Individuals with LSA-1-stimulated IL-10 responses in the dry season were less likely to become reinfected in the subsequent rainy season than those without IL-10 responses (25% versus 49%; P = 0.083). These data support the notion that maintenance of LSA-1-driven IL-10 and TNF-alpha responses requires repeated and sustained exposure to liver-stage P. falciparum. In contrast, IFN-gamma responses increase slowly with age but persist once acquired. CD8(+) T cells are the major source of IFN-gamma but may suppress production or secretion of IL-10.     

Intercostal nerve blockade versus thoracic epidural analgesia for post thoracotomy pain relief

Background Post thoractomy pain is a major source of concern in the postoperative period. The purpose of this study was to evaluate the effectiveness of intraoperative temporary intercostal nerve blockade versus thoracic epidural analgesia for control of post thoracotomy pain. Methods 40 patients undergoing elective pulmonary resection through a postero lateral thoractomy were randomly allocated to receive epidural analgesia using 0.25% bupivicaine (Group A, n=20) or temporary intercostal nerve blockade using 0.25% bupivicaine (Group B, n=20). Adequacy of analgesia was assessed over a period of 24 hours using a visual analogue score and an observer verbal ranking scale. Results Pain scores were similar in both the groups for the first 4 hours after surgery. Thereafter, the pain scores were significantly higher (p<0.05) in Group B as compared to Group A for the remainder of the observation period. There was significantly higher (p<0.01) usage, of nonsteroidal analgesic consumption in Group B. No neurological complications were encountered, in both the study groups. Conclusion We conclude that in the early postoperative period there is no significant difference in pain relief in both the techniques but there after, epidural analgesia significantly reduces post thoracotomy pain.     

Thoracic epidural infusions for post thoracotomy pain relief: a clinical study to compare the efficacy of fentanyl — bupivicaine mixtures versus fentanyl alone

Background: Optimum pain relief following thoracotomy is essential for patient comfort and to reduce the incidence of postoperative pulmonary complications. Methods: A randomized clinical trial was conducted on 90 patients scheduled for pulmonary resection. The patients were randomly divided into three groups. Group 1 received 0.125% bupivicaine with fentanyl 10μg.ml⁻¹, Group 2 received 0.25% bupivicaine with fentanyl 10μg.ml⁻¹ and Group 3 received only fentanyl 10μg.ml⁻¹ in a calculated dose as a continuous thoracic epidural infusion. Adequacy of anglesia was assessed at rest and during movement over 24 hours. Analgesic efficacy was assessed using a visual analogue score and an observer verbal ranking scale. Results: Pain scores were significantly higher in Group 3 during the assessment period. (p<0.01) as compared to the other groups. The use of intraoperative vasopressors was significantly higher (p<0.05) in Group 2 as compared to the other groups. No neurological complications were encountered in any of the study groups. Conclusion: We conclude that in the early postoperative period, the use of 0.125% bupivicaine improves fentanyl epidural analgesia in patients undergoing lung resection.     

Environmental, socio-demographic and behavioural determinants of malaria risk in the western Kenyan highlands: a case–control study

Objective  To identify risk factors for uncomplicated malaria in highland areas of East Africa at higher risk of malaria epidemics, in order to design appropriate interventions.
Methods  Prospective, population-based, case–control study in the Nandi Hills, a highland area of western Kenya, to identify environmental, sociodemographic and behavioural factors associated with clinical malaria. Data were collected using field observation, a structured questionnaire, and a global positioning system device.
Results  We interviewed 488 cases of slide-confirmed malaria and 980 age-matched controls. Multivariate analyses associated higher malaria risk with living <250 m of a forest [OR = 3.3 (95% CI 1.5, 7.1)], <250 m of a swamp [2.8 (1.3, 5.9)], <200 m of maize fields [2.0 (1.2, 3.4)], in the absence of trees <200 m [1.6 (1.2, 2.2)], on flat land [1.6 (1.2, 2.2)], in houses without ceilings [1.5 (1.1, 2.2)], in houses with a separate kitchen building [1.8 (1.4, 2.3)] and in households where the female household head had no education [1.9 (1.1, 3.1)]. Travelling out of the study site [2.2 (1.2, 4.1)] was also associated with increased risk.
Conclusions  In this East African highland area, risk of developing uncomplicated malaria was multifactorial with a risk factor profile similar to that in endemic regions. Households within close proximity to forest and swamp borders are at higher risk of malaria and should be included in indoor residual spraying campaigns.     

Impact of Body Mass Index on Left Ventricular Function

Background

Obesity is associated with increased cardiovascular morbidity and mortality. A direct effect of isolated obesity on cardiac function is not well established. The study was designed to determine the direct effect of various grades of isolated obesity on echocardiographic indices of systolic and diastolic left ventricular function.

Methods

Fifty one obese and 25 normal weight, serving personnel without any other pathological condition were studied. Group I (n=25) consisted of subjects with normal weight and body mass index (BMI <25kg/m²), Group II (n=34) of overweight subjects (BMI 25-29.9 kg/m²) and Group III (n=17) of obese subjects (BMI >30 kg/m²). Echocardiographic indices of systolic and diastolic function were obtained and dysfunction was assumed when at least two values differed by ≥ 2 SD from the normal weight group.

Result

Ejection fraction, fractional shortening were increased (p<0.05) in Group II and III. Left ventricular dimensions were increased (p< 0.001) but relative wall thickness was unchanged. Systolic dysfunction was not observed in any of the obese patients. The mitral valve pressure half time (p< 0.01), left atrial diameter (p < 0.01) and the deceleration time were increased (p< 0.01) in obese subjects, while other diastolic variables were unchanged. No difference were found between obesity subgroups. Subclinical diastolic dysfunction was more prevalent among obese subjects. BMI correlated significantly with indices of left ventricular systolic and diastolic function.

Conclusion

Subclinical left ventricular diastolic dysfunction was noted in all grades of obesity which correlates with BMI.Key Words: Obesity, Systolic function, Diastolic function, Echocardiography     

The effect of AIDS defining conditions on immunological recovery among patients initiating antiretroviral therapy at Joint Clinical Research Centre, Uganda

Background  

Many HIV-infected patients only access health care once they have developed advanced symptomatic disease resulting from AIDS Defining Conditions (ADCs). We carried out a study to establish the effect of ADCs on immunological recovery among patients initiated on antiretroviral therapy (ART).