Nanoscaled periodic surface structures of medical stainless steel and their effect on osteoblast cells

Nanoscaled lamellar surface structures have been prepared on medical stainless steel AISI 316LVM surfaces by chemical etching of the decomposed phases. The effect of this structure on osteoblastic cells has been investigated. Long filopodia were developed by the cells perpendicular to the lamellar structure while almost no or only short filopodia were formed parallel to the lamellae. These results are explained in terms of a topographical influence of the nanostructure. During the growth process of the filopodia a nearly flat surface was recognized parallel to the lamellae while a topographical change was sensed perpendicular to the structure, which was preferred by the cells.     

An empirical malaria distribution map for West Africa

The objective of this study was to produce a malaria distribution map that would constitute a useful tool for development and health planners in West Africa. The recently created continental database of malaria survey results (MARA/ARMA 1998) provides the opportunity for producing empirical models and maps of malaria distribution at a regional and eventually at a continental level. This paper reports on the mapping of malaria distribution for sub-Saharan West Africa based on these data. The strategy was to undertake a spatial statistical analysis of malaria parasite prevalence in relation to those potential bio-physical environmental factors involved in the distribution of malaria transmission intensity which are readily available at any map location. The resulting model was then used to predict parasite prevalence for the whole of West Africa. We also produced estimates of the proportion of population of each country in the region exposed to various categories of risk to show the impact that malaria is having on individual countries. The data represent a very large sample of children in West Africa. It constitutes a first attempt to produce a malaria risk map of the West African region, based entirely on malariometric data. We anticipate that it will provide useful additional guidance to control programme managers, and that it can be refined once sufficient additional data become available.     

Das hepatozellul?re Adenom: Diagnosesicherung unter besonderer Berücksichtigung von Duplexsonographie und Laparoskopie

Zusammenfassung Fallbeschreibung: Eine 46-jährige Patientin stellt sich zur weiteren Abklärung einer hausärztlich sonographisch und computertomographisch diagnostizierten isolierten Raumforderung der Leber vor. Auch die Duplexsonographie unter Verwendung eines Signalverstärkers ließ keine eindeutige Diagnosestellung zu. Die Laparoskopie zeigte makroskopisch das Bild eines Leberzelladenoms. Diese Diagnose wurde durch die histologische Aufarbeitung der entnommenen Biopsie bestätigt. Schlussfolgerung: Klinik, Diagnose, bildgebende diagnostische Verfahren und Differentialdiagnostik des Leberzelladenoms werden diskutiert. Abstract Case Report: A 46-year-old female patient presented for further investigation of an isolated liver lesion that was diagnosed by her physician by abdominal ultrasound and computertomography. The Doppler ultrasound (including a signal amplifier) could not differentiate the lesion so that a laparoscopy was performed. A hepatic adenoma was found which was confirmed by the histological examination of a directed liver biopsy. Conclusion: Signs and symptoms, diagnostic procedures and differential diagnostic options of a hepatic adenoma are discussed.     

Malaria transmission in relation to rice cultivation in the irrigated Sahel of Mali

Seven cross-sectional entomological surveys were carried out from September 1995 to February 1998 in three irrigated rice growing villages and three villages without irrigated agriculture in the area surrounding Niono, located 350km north-east of Bamako, Mali. The transmission pattern differed markedly between the two zones. In the irrigated zone, the transmission of malaria was fairly constant over the seasons at a low level. In the non-irrigated zone, transmission was mostly below detection level during the dry season, whereas it was high toward the end of the rainy season. In the irrigated zone, high densities of mosquitoes were correlated with low anthropophily, low sporozoite indices and probably low survival rates. In the non-irrigated zone, mosquito densities were lower and these relationships were less pronounced. Differential use of mosquito nets in the two zones may have been an important factor in the observed differences in transmission. The presence of cattle may also have played an important role. Two mosquito-catching methods (human landing catch and spray catch) were compared.     

Incidence of diabetic retinopathy and relationship to baseline plasma glucose and blood pressure

A nationwide, stratified population sample of 534 diabetic Swiss men and women, aged 35-54 yr, participated in a study of vascular disease. The study was based on a common protocol, standardized examination procedures, and centralized laboratory methods. Patients were chosen from a pool of diabetic Swiss with diabetes greater than or equal to 1 yr. After selection, the participants were classified into groups according to age at diabetes onset (greater than 30 or less than 30 yr) and insulin treatment status. Several variables thought to be related to retinopathy incidence were analyzed at the initial examinations: onset of diabetes before age 30, duration of disease, fasting plasma glucose, blood pressure, and insulin therapy. Follow-up examination of 358 of 458 survivors, with a diabetes duration that averaged 20 yr, showed retinopathy significantly and independently associated with initial fasting plasma glucose, systolic blood pressure, and insulin use but not with diabetes duration. Lower rates of retinopathy development were observed during the follow-up period in diabetic patients on antihypertensive therapy at the baseline examination, suggesting that not only lower fasting plasma glucose and systolic blood pressure levels but also blood pressure therapy itself decreases the incidence of retinopathy.     

Histamine receptor H1 is required for TCR-mediated p38 MAPK activation and optimal IFN-gamma production in mice

Histamine receptor H1 (H1R) is a susceptibility gene in both experimental autoimmune encephalomyelitis (EAE) and experimental autoimmune orchitis (EAO), 2 classical T cell-mediated models of organ-specific autoimmune disease. Here we showed that expression of H1R in naive CD4+ T cells was required for maximal IFN-gamma production but was dispensable for proliferation. Moreover, H1R signaling at the time of TCR ligation was required for activation of p38 MAPK, a known regulator of IFN-gamma expression. Importantly, selective reexpression of H1R in CD4+ T cells fully complemented both the IFN-gamma production and the EAE susceptibility of H1R-deficient mice. These data suggest that the presence of H1R in CD4+ T cells and its interaction with histamine regulates early TCR signals that lead to Th1 differentiation and autoimmune disease.     

Fetal haemoglobin levels in adult Type 1 (insulin-dependent) diabetic patients

Summary Glycated haemoglobin levels (HbA₁ and HbA_1c) are established parameters of long-term glycaemic control in diabetic patients. Depending on the method used, fetal haemoglobin interferes with the assays for glycated haemoglobin. If present in high amounts, fetal haemoglobin may lead to overestimation of glycated haemoglobin levels, and therefore, of average blood glucose concentration in diabetic patients. Glycated (HbA_1c) and fetal haemoglobin levels were measured by high pressure liquid chromatography in 60 (30 female) adult Type 1 (insulin-dependent) diabetic patients of Swiss descent, and were compared with levels obtained from 60 normal, non-diabetic control subjects matched for age and sex. Fetal haemoglobin levels were significantly higher in the diabetic patients (0.6±0.1%, mean±SEM; range: 0–3.6%) than in the control subjects (0.4±0.1%, p<0.001). Elevated fetal haemoglobin levels (0.6%) were found in 23 of 60 diabetic patients (38%) compared to 9 of 60 control subjects (15%; ²=8.35, p<0.01). In addition, fetal haemoglobin levels in diabetic patients are weakly correlated with glycated haemoglobin (HbA_1c) (r=0.38, p<0.01). Fetal haemoglobin results were confirmed with the alkali denaturation procedure, and by immunocytochemistry using a polyclonal rabbit anti-fetal haemoglobin antibody. A significant proportion of adult patients with Type 1 diabetes has elevated fetal haemoglobin levels. In certain patients this may lead to a substantial over-estimation of glycated haemoglobin levels, and consequently of estimated, average blood glucose levels. The reason for this increased prevalence of elevated fetal haemoglobin remains unclear, but it may be associated with poor glycaemic control.Presented in part at the 59th Annual Meeting of the Swiss Society of Internal Medicine, Lugano, 1991 and at the 14th International Diabetes Federation Congress, Washington, 1991