Human melanoma progression in skin reconstructs : biological significance of bFGF

Human skin reconstructs are three-dimensional in vitro models consisting of epidermal keratinocytes plated onto fibroblast-contracted collagen gels. Cells in skin reconstructs more closely recapitulate the in situ phenotype than do cells in monolayer culture. Normal melanocytes in skin reconstructs remained singly distributed at the basement membrane which separated the epidermis from the dermis. Cell lines derived from biologically early primary melanomas of the radial growth phase proliferated in the epidermis and the basement membrane was left intact. Growth and migration of the radial growth phase melanoma cells in the dermal reconstruct and tumorigenicity in vivo were only observed when cells were transduced with the basic fibroblast growth factor gene, a major autocrine growth stimulator for melanomas. Primary melanoma cell lines representing the more advanced stage vertical growth phase invaded the dermis in reconstructs and only an irregular basement membrane was formed. Metastatic melanoma cells rapidly proliferated and aggressively invaded deep into the dermis, with each cell line showing typical invasion and growth characteristics. Our results demonstrate that the growth patterns of melanoma cells in skin reconstructs closely correspond to those in situ and that basic fibroblast growth factor is critical for progression.     

Understanding Inequities in Child Vaccination Rates among the Urban Poor: Evidence from Nairobi and Ouagadougou Health and Demographic Surveillance Systems

Studies on informal settlements in sub-Saharan Africa have questioned the health benefits of urban residence, but this should not suggest that informal settlements (within cities and across cities and/or countries) are homogeneous. They vary in terms of poverty, pollution, overcrowding, criminality, and social exclusion. Moreover, while some informal settlements completely lack public services, others have access to health facilities, sewers, running water, and electricity. There are few comparative studies that have looked at informal settlements across countries accounting for these contextual nuances. In this paper, we comparatively examine the differences in child vaccination rates between Nairobi and Ouagadougou’s informal settlements. We further investigate whether the identified differences are related to the differences in demographic and socioeconomic composition between the two settings. We use data from the Ouagadougou and Nairobi Urban Health and Demographic Surveillance Systems (HDSSs), which are the only two urban-based HDSSs in Africa. The results show that children in the slums of Nairobi are less vaccinated than children in the informal settlements in Ouagadougou. The difference in child vaccination rates between Nairobi and Ouagadougou informal settlements are not related to the differences in their demographic and socioeconomic composition but to the inequalities in access to immunization services.     

Cardiac manifestations of sickle cell anemia

HEMOGLOBINS S AND C: Drepanocytosis, the occurrence of sickle cells (drepanocytes) in the blood, is an inherited condition. Electrophoresis demonstrates hemoglobin SS in homozygous subjects who present the typical clinical features of severe hemolytic sickle-cell anemia. Heterozygous subjects have sickle-cell anemia trait, an asymptomatic condition associated with a 50% hemoglobin S and 50% hemoglobin C at electrophoresis. Hemoglobin S and C are transmitted by Mendelian inheritance. CARDIAC DISORDERS: Well-known, cardiac disorders occur in more than 82% of homozygous subjects while only 2% of heterozygous subjects are affected. Heart murmur, radiological cardiomegaly, or eletrocardiographic anomalies are often the only signs. There is a risk of fatal heart failure in children and neonates. Acute rheumatic fever or infectious endocarditis, particularly due to pneumococcal or Haemophilus influenzae infection, may trigger heart failure. CARDIAC ANOMALIES: Patients with sickle-cell anemia can develop an "anemic heart" expressed by an elevated cardiac output and systemic ejection volume at rest and a fall in arteriolar peripheral resistance. Patients who develop cor pulmonae have an elevated pulmonary pressure at exercise and experience venous occlusive events with a progressive reduction in the pulmonary vascular bed and development of a left-right shunt. Myocardiopathy leads to left ventricular dysfunction contrasting with the dilated right heart seen at echocardiography and rare cases of transmural infarction.     

Bouillaud's disease in Martinique. Epidemiological and nosological features]

From the epidemiological point of view there does not appear to be any particular geographical pattern of this disease. Indeed, it is poor living conditions, low family income, large family size and poor oro-dental hygiene which are responsable for the outbreak of small familial epidemics of acute rheumatic disease of the joints; from the clinical point of view, acute rheumatic joint disease presents no particular features in the Antilles. All the characteristics described in the classical works are found, including the malignant form, whose rarity is emphasised. A programme of prevention of rheumatic disease has yet to be started in the Antilles, and we feel that it should be a three-pronged attack: 1. More information to the general public on the necessity for rapid treatment of the symptoms; 2. Increased vigilance by the medical services in the fight against this disease of deprivation, and close collaboration with the social services; 3. Finally, the setting up of a specialised social cardiology service to supervise the young rheumatic patients, and to ensure that they are educated. Such arrangements would avoid the disorganisation sometimes experienced by the families and friends; it must be admitted that we sometimes have to prevail upon the family to allow the child to be transferred to a centre of social cardiology on the continent so that the young rheumatic patient may receive training for a career which is compatible with his or her handicap.     

Bioassay-Guided Isolation of Antimalarial Triterpenoid Acids from the Leaves of Morinda lucida.

Abstract

The EtOH, CH₂Cl₂, and petroleum ether extracts from Morinda lucida. Benth. leaves have been shown to exhibit an in vitro. antiplasmodial activity against a chloroquine-sensitive Plasmodium falciparum. strain with IC₅₀ values 5.7 ± 1.3, 5.2 ± 0.8, and 3.9 ± 0.3 µg/mL, respectively. In vivo., at a daily oral dose of 200 mg/kg body weight, they produced at least 62.5%, 67.5%, and 72.2% reduction of parasitemia in mice infected with Plasmodium berghei berghei., respectively. A bioassay-guided fraction of the most active petroleum ether extract resulted in the isolation of two known triterpenic acids as ursolic acid 1 and oleanolic acid 2. In vitro., 1 and 2 exhibited an antiplasmodial activity with IC₅₀ values of 3.1 ± 1.3 and 15.2 ± 3.4 µg/mL, respectively. In vivo., at a daily dose of 200 mg/kg body weight, they produced 97.7% and 37.4% chemosuppression, respectively. However, all tested samples were inactive in vitro. against chloroquine-resistant Plasmodium falciparum. (K1) at the highest tested concentration of 25 µg/mL.     

The leaf extract of Spondias mombin L. displays an anti-inflammatory effect and suppresses inducible formation of tumor necrosis factor-α and nitric oxide (NO)

Extracts of Spondias mombin L. (Anacardiacea) is used in the traditional medicine of Africa and Latin America to treat many inflammatory conditions, with repeated claims of efficacy. However, there are no scientific data yet to support these claims and the mechanism through which the extract may be acting is still unknown. This study was undertaken to investigate the effects of the methanolic extract of the leaf of S. mombin (SM) on inflammation and to uncover some of the possible mechanisms that could explain any observed changes. The anti-inflammatory activity of the extract was investigated in Wistar rats using intraplantar injection of carrageenan as an in vivo model of inflammation. The effect of oral supplementation of the SM extract on tumor necrosis factor (TNF)-α levels after an intraperitoneal lipopolysaccharide (LPS; 1 mg/kg) challenge was investigated in mice. The effect of SM on TNF-α and inducible nitric oxide (iNO) production by LPS-stimulated bone marrow-derived macrophages (BM-M?) was also investigated in vitro. BM-M? were preincubated for 2 h with SM (0-100 μg/ml), activated with LPS, and then TNF-α and NO production measured in the cell-free conditioned culture supernatant after 24 h of incubation. The study showed that pre-treatment of rats with the SM extract (at 100, 200, and 400 mg/kg, per os) caused a significant dose-related inhibition of carrageenan-induced paw edema over a 4-h period. In treated mice, LPS-inducible (systemic) TNF-α levels were found to be significantly lower as a result of their receiving the SM extract. In vitro, SM treatment caused a dose-dependent decrease in LPS-inducible TNF-α and NO production by BM-M? compared to the effects of treatment of the cells with LPS alone. Taken together, the results of these studies suggest that supplementation with SM extract can alleviate inflammatory responses and that this could possibly be via a suppression of the production of pro-inflammatory mediators and cytokines such as TNF-α and iNO.     

In Vivo Measurements of Cortical Thickness and Porosity at the Proximal Third of the Tibia Using Guided Waves: Comparison with Site-Matched Peripheral Quantitative Computed Tomography and Distal High-Resolution Peripheral Quantitative Computed Tomography

The aim of this study was to estimate cortical porosity (Ct.Po) and cortical thickness (Ct.Th) using 500-kHz bi-directional axial transmission (AT). Ct.Th_AT and Ct.Po_AT were obtained at the tibia in 15 patients from a 2-D transverse isotropic free plate model fitted to measured guided wave dispersion curves. The velocities of the first arriving signal (υ_FAS) and A₀ mode (υ_A0) were also determined. Site-matched peripheral quantitative computed tomography (pQCT) provided volumetric cortical bone mineral density (Ct.vBMD_pQCT) and Ct.Th_pQCT. Good agreement was found between Ct.Th_AT and Ct.Th_pQCT (R²?=?0.62, root mean square error [RMSE]?=?0.39 mm). Ct.vBMD_pQCT correlated with Ct.Po_AT (R²?=?0.57), υ_FAS (R²?=?0.43) and υ_A0 (R²?=?0.28). Furthermore, a significant correlation was found between AT and distal high-resolution pQCT. The measurement ofcortical parameters at the tibia using guided waves might improve the prediction of bone fractures in a cost-effective and radiation-free manner.