Gender and adult undernutrition in developing countries

Background: Information on the prevalence of undernutrition in adults in developing countries is mainly restricted to data on women. Literature reporting on the occurrence of female deprivation in developing countries, in particular in South Asia, suggests that differences between undernutrition prevalence in adult men and adult women might occur, but systematic information on the subject is lacking. Aim: The study compares undernutrition prevalence rates, based on prevalence of low body mass index (BMI < 18.5), in adult men and adult women in developing countries. Regional comparison is made between the main developing regions: Sub-Saharan Africa, South/Southeast Asia and Latin America. Subjects and methods: The study uses data as reported in 75 samples from 31 countries (divided over the three developing regions), in which anthropometric information has been collected in adult men and women within one and the same community. Results: Results indicate that, in general, prevalence rates of undernutrition are rather similar in adult men and women. However, there are regional differences. In communities in Sub-Saharan Africa, prevalence of low BMI is, on average, a few percent higher in men than in women; in South/Southeast Asia the reverse is the case. In some communities differences in undernutrition prevalence between men and women are exceptionally large. Conclusions: It can be concluded that, in general, information on undernutrition prevalence in women can be considered a proxy for undernutrition prevalence in all adults, men and women together. However, the finding that in South/Southeast Asia women's nutritional status relative to men's nutritional status compares unfavourably with results from other developing regions, in particular Sub-Saharan Africa, provides some support for the concept of female deprivation in South/Southeast Asia. Where large differences between prevalence of low BMI in men and women occur, gender-specific policies aimed at reducing undernutrition should be considered.     

Pilot study on the influence of liver blood flow and cardiac output on the clearance of propofol in critically ill patients

Objective To investigate the effect of cardiac output and liver blood flow on propofol concentrations in critically ill patients in the intensive care unit. Methods Five medical/surgical critically ill patients were enrolled in this preliminary study. Liver blood flow was measured using sorbitol. The cardiac output was measured by bolus thermodilution. NONMEM ver. V was applied for propofol pharmacokinetic analysis. Results The clearance of propofol was positively influenced by the liver blood flow (P < 0.005), whereas no significant correlation between cardiac output and propofol clearance was found. A correlation between liver blood flow and cardiac output or cardiac index could not be assumed in this patient group. Conclusions Liver blood flow is a more predictive indicator than cardiac output for propofol clearance in critically ill patients when the techniques of hepatic sorbitol clearance and bolus thermodilution, respectively, are used. Further study is needed to determine the role played by liver blood flow and cardiac output on the pharmacokinetics of highly extracted drugs in order to reduce the observed high interindividual variabilities in response in critically ill patients.     

Human immunity to M. tuberculosis: T cell subsets and antigen processing

A hallmark of M. tuberculosis infection is the ability of most (90-95%) healthy adults to control infection through acquired immunity, in which antigen specific T cells and macrophages arrest growth of M. tuberculosis bacilli and maintain control over persistent bacilli. In addition to CD4+ T cells, other T cell subsets such as, gammadelta, CD8+ and CD1-restricted T cells have roles in the immune response to M. tuberculosis. A diverse T cell response allows the host to recognize a wider range of mycobacterial antigens presented by different families of antigen-presenting molecules, and thus greater ability to detect the pathogen. Macrophages are key antigen presenting cells for T cells, and M. tuberculosis survives and persists in this central immune cell. This is likely an important factor in generating this T cell diversity. Furthermore, the slow growth and chronic nature of M. tuberculosis infection results in prolonged exposure to antigens, and hence further T cell sensitization. The effector mechanisms used by T cells to control M. tuberculosis are poorly understood. To survive in macrophages, M. tuberculosis has evolved mechanisms to block immune responses. These include modulation of phagosomes, neutralization of macrophage effector molecules, stimulating the secretion of inhibitory cytokines, and interfering with processing of antigens for T cells. The relative importance of these blocking mechanisms likely depends on the stage of M. tuberculosis infection: primary infection, persistence, reactivation or active tuberculosis. The balance of the host-pathogen interaction in M. tuberculosis infection is determined by the interaction of T cells and infected macrophages. The outcome of this interaction results either in control of M. tuberculosis infection or active disease. A better understanding of this interaction will result in improved approaches to treatment and prevention of tuberculosis.     

No influence of melatonin on cerebral blood flow in humans

Melatonin has been attributed a role in a number of physiological processes. Changes in distal skin temperature and blood pressure after intake of melatonin suggest that melatonin induces peripheral vasodilation. The effect on the cerebral blood flow is still unknown. We examined the effect of a single pulse of melatonin on cerebral and peripheral blood flow, using the latter as a positive control. Ten male healthy volunteers (mean age, 22 +/- 3.2 yr) participated in a double-blind, randomized, placebo-controlled, cross-over study. On one occasion 10 microg melatonin were infused i.v., and on the other occasion saline was infused as the matching placebo. Cerebral blood flow was measured using phase contrast magnetic resonance imaging. Peripheral blood flow was determined from changes in the distal to proximal skin temperature gradient and finger pulse volume. Serum melatonin concentration increased from 12 +/- 5 pg/ml at baseline to 487 +/- 377 pg/ml at 5 min and 156 +/- 68 pg/ml at 10 min after melatonin administration. There was no significantly different time course for cerebral blood flow and cerebrovascular resistance. Compared with placebo, melatonin significantly increased peripheral blood flow, as measured by distal to proximal skin temperature gradient and finger pulse volume. These data demonstrate that melatonin does not have an acute regulatory effect on cerebral blood flow in humans.     

Thermographic skin temperature measurement compared with cold sensation in predicting the efficacy and distribution of epidural anesthesia

Due to the high rates of epidural failure (3–32%), novel techniques are required to objectively assess the successfulness of an epidural block. In this study we therefore investigated whether thermographic temperature measurements have a higher predictive value for a successful epidural block when compared to the cold sensation test as gold standard. Epidural anesthesia was induced in 61 patients undergoing elective abdominal, thoracic or orthopedic surgery. A thermographic picture was recorded at 5, 10 and 15 min following epidural anesthesia induction. After 15 min a cold sensation test was performed. Epidural anesthesia is associated with a decrease in skin temperature. Thermography predicts a successful epidural block with a sensitivity of 54% and a PPV of 92% and a specificity of 67% and a NPV of 17%. The cold sensation test shows a higher sensitivity and PPV than thermography (97 and 93%), but a lower specificity and NPV than thermography (25 and 50%). Thermographic temperature measurements can be used as an additional and objective method for the assessment of the effectiveness of an epidural block next to the cold sensation test, but have a low sensitivity and negative predictive value. The local decrease in temperature as observed in our study during epidural anesthesia is mainly attributed to a core-to-peripheral redistribution of body heat and vasodilation.     

Undetectable Viral Load and the Decision to Engage in Unprotected Anal Intercourse Among HIV-Positive MSM

We investigated how often HIV-positive MSM (n = 177) decide to engage in unprotected anal intercourse (UAI) because they have an undetectable viral load (UVL). We found that 20–57 % of the UAI acts were related to having UVL, varying by partner type and partner HIV status. Among HIV-concordant partners, consideration of UVL before engaging in UAI was more prevalent with sex buddies (55 %) than with casual partners (20 %), although marginally significant (p = 0.051). Among HIV-discordant partners, no significant difference was found in the frequency of UVL considerations before engaging in UAI: 40 % with sex buddies versus 57 % with casual partners. Interestingly, while the decision to engage in UAI based on UVL was frequently discussed with HIV-concordant partners (>91 %), it was only discussed with HIV-discordant partners in 13–25 % of the UAI cases (according to partner type), suggesting that the decision was mostly unilateral.     

Long-term bone marrow cultured stromal cells regulate myeloma tumour growth in vitro: studies with primary tumour cells and LTBMC-dependent cell lines

Long-term bone marrow cultured stromal cells (LTBMC) produce IL-6 after contact with tumour cells from multiple myeloma patients. We found that LTBMC could substitute for exogenous IL-6 in the stimulation of bone marrow plasma cells from myeloma patients with active disease in short-term cultures. In addition, tumour cells of some patients with inactive disease, which were unresponsive to exogenous IL-6, were induced to IL-6-dependent growth after LTBMC co-culture. To study the role of LTBMC in myeloma tumour growth in vitro , plasma cell lines UM-2 and UM-3 were selected. UM-2 and UM-3 grew in contact with LTBMC and proliferation was blocked by antibodies against IL-6, IL-6 receptor (IL-6R, gp80, CD126) or the common signal transducing unit, gp130 (CD130). Culture with IL-6 alone or combined with GM-CSF resulted in cell death via apoptosis. The combination of IL-6 with soluble gp80, however, maintained in vitro proliferation of UM-2 and UM-3 cells. These data imply that LTBMC regulate myeloma growth in vitro via production of IL-6, possibly via induction of a functional IL-6 receptor on the tumour cells.     

Quality of life of patients with irritable bowel syndrome is low compared to others with chronic diseases

BACKGROUND: Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal dysmotility disorder. This study aimed to estimate the burden of illness of a Dutch population of community dwelling patients suffering from IBS. METHODS: Patients identified at community pharmacies, using mebeverine as a proxy for IBS, were administered a questionnaire regarding (1) the Rome II criteria for IBS, (2) predominant type of stool during complaints, (3) severity of symptoms (abdominal pain and discomfort), (4) generic and disease-specific quality of life, (5) current health status (utilities), and (6) loss of productivity. RESULTS: Three hundred and seventy-five users of mebeverine were identified of which 169 patients met the Rome II criteria for IBS, and were included in the study. More than half (58%) of the IBS patients reported severe abdominal pain and complaints. Generic and disease-specific quality of life outcomes showed impairment on all dimensions. Current health status in IBS patients, calculated on the basis of the EQ-5D VAS, was perceived on 62% of full health (95% CI, 60-66%). A calculation of health status in these patients based on the SF-6D algorithm showed a comparable score of 0.67 (1 is full health; 95% CI, 0.65-0.68). The loss in productivity of IBS patients was 1.8 days (95% CI, 1.1-2.5) per month. CONCLUSIONS: This study confirmed that the burden of illness of IBS in the Netherlands is substantial. IBS patients treated with mebeverine experienced low quality of life and suffered from severe pain. Based on these results, more attention for the diagnosis and treatment of IBS seems to be justified.