Global Perspective of the Vitamin D Status of African-Caribbean Populations: A Systematic Review and Meta-analysis

Background/Objectives Vitamin D deficiency remains a global public health issue, particularly in minority ethnic groups. This review investigates the vitamin D status (as measured by 25(OH)D and dietary intake) of the African-Caribbean population globally. Subjects/Methods A systematic review was conducted by searching key databases (PUBMED, Web of Science, Scopus) from inception until October 2019. Search terms included ‘Vitamin D status’ and ‘African-Caribbean’. A random effects and fixed effects meta-analysis was performed by combining means and standard error of the mean. Result The search yielded 19 papers that included n = 5670 African-Caribbean participants from six countries. A meta-analysis found this population to have sufficient (>50 nmol/L) 25(OH)D levels at 67.8 nmol/L, 95% CI (57.9, 7.6) but poor dietary intake of vitamin D at only 3.0 µg/day, 95% CI (1.67,4.31). For those living at low latitudes ‘insufficient’ (as defined by study authors) 25(OH)D levels were found only in participants with type 2 diabetes and in those undergoing haemodialysis. Suboptimal dietary vitamin D intake (according to the UK recommended nutrient intake of 10 µg/day) was reported in all studies at high latitudes. Studies at lower latitudes, with lower recommended dietary intakes (Caribbean recommended dietary intake: 2.5 µg/day) found ‘sufficient’ intake in two out of three studies. Conclusions 25(OH)D sufficiency was found in African-Caribbean populations at lower latitudes. However, at higher latitudes, 25(OH)D deficiency and low dietary vitamin D intake was prevalent.

The in vitro antisickling effect of purified alkaloids of Cremaspora triflora (Thonn.) K. Schum. (Rubiaceae) and Macaranga schweinfurthii Pax. (Euphorbiaceae)

Introduction and objective: Sickle cell disease is an inherited pathology to an abnormality of hemoglobin precisely hemoglobin S for which there is no curative therapy. It mainly affects sub-Saharan African and Caribbean populations. Thus, this study aims to make the phytochemical screening of Cremaspora triflora and Macaranga schweinfurthii as well as to evaluate the antisickling activity of their purified alkaloids. Methodology: Chemical screening was performed using color and precipitation tests as well as the foam index method. The extraction of the alkaloids was carried out with organic solvents in a basic medium while the purification by open column chromatography. The evaluation of the antisickling activity was carried out by Emmel’s test. Results: The chemical screening highlighted alkaloids, steroids, saponins, tannins, and terpenoids in the species studied. Flavonoids and anthocyanins were present in organs of Macaranga schweinfurthii, but absent in Cremaspora triflora. The extraction showed that Macaranga schweinfurthii leaves contained 0.59% alkaloids and 0.73% alkaloids in Cremaspora triflora leaves. The alkaloids purification allowed to obtain an alkaloidal fraction MS1 (1.24 g, 70.05%) from Macaranga schweinfurthii and two fractions [CT2 (0.934 g, 63.97%) and CT3 (0.006 g, 0.41 %)] from Cremaspora triflora which tested positive with Dragendorff and Wagner reagents. The antisickling activity evaluation showed that the SIR varied between 36.00% (0.25 mg/ml) and 90.66% (1 mg/ml) for the alkaloid solutions of Cremaspora triflora (IC50 of 0.51 mg/ml) as well as between 4.00% (0.25 mg/ml) and 33.33% (1 mg/ml) for the alkaloid solutions of Macaranga schweinfurthii (IC50 of 1.40 mg/ml). Conclusion: This study showed that the purified alkaloids of the studied plant species have an inhibitory power on sickling.

Testing for phylogenetic signal in claws suggests great influence of ecology on Caribbean intertidal arthropods (Acari, Oribatida)

Claws are common biological attachment devices that can be found in a wide variety of animal groups. Their curvature and size are supposed to be parameters related to ecological aspects. Mites, known as very small arthropods, occupy a wide range of ecological niches and are a perfect model system to investigate correlations of claw morphology with ecology. There is only one study regarding this question in littoral mites but the phylogenetic impact, which plays an important role in the evolution of morphological traits, was not tested. We investigated claw shapes of different Caribbean populations of five species showing different substrate/habitat preferences. We used geometric morphometrics to quantify claw shape and tested for phylogenetic signal within this morphological trait. Even in closely related populations, we found clear claw shapes for hard versus soft substrate, confirming previous findings. Surprisingly, we found no phylogenetic signal within the trait, which demonstrates that ecology (different surfaces and substrates) has acted as one of the primary selective forces in the diversification of claw shapes. Considering that the basic claw design may be the same in the majority of arthropods, our results have important implications for further investigations of claw morphology and its ecological relevance within this phylum.

Prevalence, prognosis, and treatment of atherosclerotic intracranial stenosis in Caucasians

Background Intracranial atherosclerotic stenosis is a highly prevalent cause of stroke worldwide with important ethnic disparities. Widely considered to be a common cause of stroke in Asian and Afro-Caribbean populations, relatively less is known about the burden and significance of intracranial atherosclerotic stenosis in Caucasians. Aims We aim to highlight recent insights and advances into the prevalence, prognosis, and treatment of symptomatic and asymptomatic atherosclerotic intracranial atherosclerotic stenosis in Caucasian patients. Summary of review We identified 48 articles studying intracranial atherosclerotic stenosis in Caucasian patients with ischemic stroke or transient ischemic attack. Most studies were on hospital-based cohorts of consecutive patients and half were graded as “fair” quality. There was significant variation between studies in the definition of intracranial atherosclerotic stenosis and in the imaging modalities used to detect intracranial atherosclerotic stenosis. Overall, 12.1% of Caucasian patients were found to have any intracranial atherosclerotic stenosis, 6.4% symptomatic intracranial atherosclerotic stenosis and 11.1% asymptomatic intracranial atherosclerotic stenosis, with higher rates at older ages. In studies reporting prognosis, there were 61 and 10 same-territory ischemic strokes in 1000 person-years in patients with symptomatic and asymptomatic intracranial atherosclerotic stenosis, respectively. Percutaneous stenting and angioplasty have not proven superior to intensive medical management in patients with symptomatic intracranial atherosclerotic stenosis. Conclusions Intracranial atherosclerotic stenosis has previously been neglected as a cause of stroke in Caucasians but is highly prevalent at older ages and frequently discovered with the growing use of noninvasive angiography. Intensive medical therapy is the treatment of choice, but there is a need to develop novel treatments or therapeutic approaches to lower the risk of stroke in higher risk patients.

Carnival as Contentious Performance

In the 1970s, in a context of increased racial tensions and growing nationalist claims, the use of rhythms, instruments, and clothing associated with Africa among the black populations of England, Guadeloupe, and Martinique became part of a cultural and political repertoire aimed at resurrecting and denouncing a long history of subordination. Similarly, the mobilization of carnival by Afro-Caribbean activists today can be considered as a tactical choice—that is to say, carnival has become part of the standardized, limited, context-dependent repertoires from which claim-making performances are drawn. Based on ethnographic fieldwork conducted in Fort-de-France, London, and Pointe-à-Pitre between 2000 and 2018, this article analyzes how cultural movements have drawn on carnivalesque aesthetics to both memorialize and display the complex history of black Caribbean populations. I argue that Caribbean carnival has been subject to constant reinterpretations since the eighteenth century and that, as such, this repertoire is not only a model or a set of limited means of action, but also a convention through which carnival groups constantly reinvent their skills and resources. Furthermore, this article shows that the repertoires mobilized by the carnival bands I study in Europe and in the Caribbean cannot be reduced to an aesthetic gesture that serves political claims, and that they are part of a historical genealogy that testifies to the irreducible character of a way of life.

Prevalence of the BRAF p.v600e variant in patients with colorectal cancer from Mexico and its estimated frequency in Latin American and Caribbean populations

This study aimed to investigate the frequency of the somatic BRAF p.V600E in patients with colorectal cancer (CRC) in Mexico and compare it with those estimated for Latin American and Caribbean populations. One hundred and one patients with CRC with AJCC stages ranging I–IV from Western Mexico were included, out of which 55% were male and 61% had AJCC stage III–IV, with a mean age of 60 years. PCR-Sanger sequencing was used to identify the BRAF p.V600E variant. In addition, a systematic literature search in PubMed/Medline database and Google of the 42 countries in Latin America and the Caribbean led to the collection of information on the BRAF p.V600E variant frequency of 17 population reports. To compare the BRAF variant prevalence among populations, a statistical analysis was performed using GraphPad Prism V.6.0. We found that 4% of patients with CRC were heterozygous for the p.V600E variant. The χ2 test showed no significant difference (p>0.05) in p.V600E detection when comparing with other Latin American and Caribbean CRC populations, except for Chilean patients (p=0.02). Our observational study provides the first evidence on the frequency of BRAF p.V600E in patients with CRC from Western Mexico, which is 4%, but increases to 7.8% for all of Latin America and the Caribbean. The patient mean age and genetic descent on the observed frequencies of the variant in populations could influence the frequency differences.