Search results for "African"

Structure, interdomain dynamics, and pH-dependent autoactivation of pro-rhodesain, the main lysosomal cysteine protease from African trypanosomes

2021

AbstractRhodesain is the lysosomal cathepsin L-like cysteine protease ofT. brucei rhodesiense, the causative agent of Human African Trypanosomiasis. The enzyme is essential for the proliferation and pathogenicity of the parasite as well as its ability to overcome the blood-brain barrier of the host. Lysosomal cathepsins are expressed as zymogens with an inactivating pro-domain that is cleaved under acidic conditions. A structure of the uncleaved maturation intermediate from a trypanosomal cathepsin L-like protease is currently not available. We thus established the heterologous expression ofT. brucei rhodesiensepro-rhodesain inE. coliand determined its crystal structure. The trypanosomal pr…

The discovery of novel antitrypanosomal 4-phenyl-6-(pyridin-3-yl)pyrimidines

2021

Human African trypanosomiasis, or sleeping sickness, is a neglected tropical disease caused by Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense which seriously affects human health in Africa. Current therapies present limitations in their application, parasite resistance, or require further clinical investigation for wider use. Our work herein describes the design and syntheses of novel antitrypanosomal 4-phenyl-6-(pyridin-3-yl)pyrimidines, with compound 13, the 4-(2-methoxyphenyl)-6-(pyridine-3-yl)pyrimidin-2-amine demonstrating an IC50 value of 0.38 μM and a promising off-target ADME-Tox profile in vitro. In silico molecular target investigations showed rhodesain to be a pu…

Intraseasonal variations of June?September rainfall and upper-air circulation over Kenya

1996

In the Northern Summer, Kenya is located under the influence of the divergent Indian monsoon flow, and therefore is dry except for two separate areas: the coastal strip and the western regions. Analysis of daily rainfall data for June–September 1982 to 1988 has revealed that, although there are many distinct rainfall events between the two regions, an out-of-phase relationship is also evident, rain on the Coast being frequently accompanied by a drop in the precipitation over the Rift Valley area. It is shown that two types of wind forcing accompany these patterns. Alternating westerly and easterly anomalies at the 700 hPa level are associated with persistent wet and dry conditions (respecti…

Role of Indian fluxes in the intraseasonal 10-30 days variability of the African monsoon.

2018

12 pages; International audience; This study focused on the influence of Indian monsoon on the 10-30 days variability of the West African monsoon. One relies on the 500-300 hPa moisture fluxes calculated from specific wind and moisture fields from the ERAInterim reanalysis over the 1998-2008 period. These fluxes carry a signal of a spatio-temporal Rossby wave structure propagating westward from India. In the active phase of high convection of this wave, 500-300 hPa fluxes are Easterly. This high-tropospheric Rossby wave signal from the Indian monsoon area would modulate the dynamics over the Sahel.

Mountain-building under extension

2013

A mechanism is presented which explains how intra-continental rifting can cause large topographic uplift. The effect is sufficient to account for the uplift of rift flanks and the very high and strongly localized uplift of the Rwenzori horst in the Western Branch of the East African Rift System. We propose that the uplift is generated by crustal bending, which is caused by a misfit of the lateral tensile stress between the upper and middle crust. The misfit is a function of different yield mechanisms when the upper crust breaks whereas the middle crust flows. Two independent numerical schemes confirm the suggested uplift mechanism. Both models—a 2 and 2.5 D elastoplastic lattice-particle mo…

Akragas: il fronte dell'Africa. Opportunità del fenomeno migratorio

2008

Oldest Homo and Pliocene biogeography of the Malawi Rift

1993

The Malawi Rift and Pliocene palaeofaunas, which include a hominid mandible attributed to Homo rudolfensis, provide a biogeographical link between the better known Plio-Pleistocene faunal records of East and Southern Africa. The Malawi Rift is in a latitudinal position suitable for recording any hominid and faunal dispersion towards the Equator that was brought on by increased aridity of the Late Pliocene African landscape. The evidence suggests that Pliocene hominids originated in the eastern African tropical domain and dispersed to southern Africa only during more favourable ecological circumstances.

Functional characterization of protein variants of the human multidrug transporter ABCC2 by a novel targeted expression system in fibrosarcoma cells

2012

The multidrug resistance-associated protein 2 (MRP2/ABCC2) is involved in the efflux of endogenous and xenobiotic substrates, including several anticancer and antiviral drugs. The functional consequences of ABCC2 protein variants remain inconsistent, which may be due to shortcomings of the in vitro assays used. To study systematically the functional consequences of nonsynonymous ABCC2 variants, we used a novel “Screen and Insert” (ScIn) technology to achieve stable and highly reproducible expression of 13 ABCC2 variants in HT1080 cells. Western blotting revealed lower (30–65%) ABCC2 expression for D333G, R1174H, and R1181L as compared with wild type (WT; 100%), whereas the linked variant V1…

OHADA: Lei da arbitragem e a harmonizaçao do direito comercial em Africa

2008

L'aricolo esamina il regime dell'arbitrato nell'ambito del diritto commerciale armonizzato dell'OHADA.

“I take an oath to the state, not the government”: Career Trajectories and Professional Ethics of Ghanaian Public Servants

2014

This chapter explores normative statements and narratives that feature role models or castigate discrimination and patronage. It argues that these ideals and stories create moral boundaries and support an 'esprit de corps' of dedicated public servants. The chapter discusses how such particularist identities are mobilised in the construction of a universalist ethos of public service. It gives an overview of the educational background of the public servants. The chapter discusses their experiences and views with respect to two major themes: firstly, the motivation to join the public service and the factors they identify as determining their own and other public servants' career trajectories; …