Active travel and paratransit use in African cities: Mixed-method systematic review and meta-ethnography.

Active travel, as a key form of physical activity, can help offset noncommunicable diseases as rapidly urbanising countries undergo epidemiological transition. In Africa a human mobility transition is underway as cities sprawl and motorization rises and preserving active travel modes (walking, cycling and public transport) is important for public health. Across the continent, public transport is dominated by paratransit, privately owned informal modes serving the general public. We reviewed the literature on active travel and paratransit in African cities, published from January 2008 to January 2019. We included 19 quantitative, 14 mixed-method and 8 qualitative studies (n = 41), narratively synthesizing the quantitative data and meta-ethnographically analysing the qualitative data. Integrated findings showed that walking was high, cycling was low and paratransit was a critical mobility option for poor peripheral residents facing long livelihood-generation journeys. As an indigenous solution to dysfunctional mobility systems shaped by colonial and apartheid legacies it was an effective connector, penetrating areas unserved by formal public transport and helping break cycles of poverty. From a public health perspective, it preserved active travel by reducing mode-shifting to private vehicles. Yet many city authorities viewed it as rogue, out of keeping with the 'ideal modern city', adopting official anti-paratransit stances without necessarily considering the contribution of active travel to public health. The studies varied in quality and showed uneven geographic representation, with data from Central and Northern Africa especially sparse; notably, there was a high prevalence of non-local authors and out-of-country funding. Nevertheless, drawing together a rich cross-disciplinary set of studies spanning over a decade, the review expands the literature at the intersection of transport and health with its novel focus on paratransit as a key active travel mode in African cities. Further innovative research could improve paratransit's legibility for policymakers and practitioners, fostering its inclusion in integrated transport plans.

Socioeconomic and gendered inequities in travel behaviour in Africa: Mixed-method systematic review and meta-ethnography.

Travel has individual, societal and planetary health implications. We explored socioeconomic and gendered differences in travel behaviour in Africa, to develop an understanding of travel-related inequity. We conducted a mixed-methods systematic review (PROSPERO CRD42019124802). In 2019, we searched MEDLINE, TRID, SCOPUS, Web of Science, LILACS, SciELO, Global Health, Africa Index Medicus, CINAHL and MediCarib for studies examining travel behaviour by socioeconomic status and gender in Africa. We appraised study quality using Critical Appraisal Skills Programme checklists. We synthesised qualitative data using meta-ethnography, followed by a narrative synthesis of quantitative data, and integrated qualitative and quantitative strands using pattern matching principles. We retrieved 103 studies (20 qualitative, 24 mixed-methods, 59 quantitative). From the meta-ethnography, we observed that travel is: intertwined with social mobility; necessary to access resources; associated with cost and safety barriers; typified by long distances and slow modes; and dictated by gendered social expectations. We also observed that: motorised transport is needed in cities; walking is an unsafe, 'captive' mode; and urban and transport planning are uncoordinated. From these observations, we derived hypothesised patterns that were tested using the quantitative data, and found support for these overall. In lower socioeconomic individuals, travel inequity entailed reliance on walking and paratransit (informal public transport), being unable to afford travel, travelling less overall, and travelling long distances in hazardous conditions. In women and girls, travel inequity entailed reliance on walking and lack of access to private vehicles, risk of personal violence, societally-imposed travel constraints, and household duties shaping travel. Limitations included lack of analytical rigour in qualitative studies and a preponderance of cross-sectional quantitative studies (offering a static view of an evolving process). Overall, we found that travel inequity in Africa perpetuates socioeconomic and gendered disadvantage. Proposed solutions focus on improving the safety, efficiency and affordability of public transport and walking.

Enzymatic conversion of magnetic nanoparticles to a non-magnetic precipitate: a new approach to magnetic sensing.

Magnetic sensing utilizes the detection of biomolecule-conjugated magnetic nanoparticles (MNPs). Our new strategy offers a novel approach to magnetic sensing where in situ conversion produces a "loss of signal" in the sensing device. This report demonstrates the enzymatic conversion of Fe3O4 MNPs to a non-magnetic precipitate via reduction by l-ascorbic acid generated by the action of alkaline phosphatase.

Multi-responsive hybrid particles: thermo-, pH-, photo-, and magneto-responsive magnetic hydrogel cores with gold nanorod optical triggers.

The research strategy described in this manuscript harnesses the attractive properties of hydrogels, gold nanorods (Aurods), and magnetic nanoparticles (MNPs) by synthesizing one unique multi-responsive nanostructure. This novel hybrid structure consists of silica-coated magnetic particles encapsulated within a thermo-responsive P(NIPAM-co-AA) hydrogel network on which Aurods are assembled. Furthermore, this research demonstrates that these composite particles respond to several forms of external stimuli (temperature, pH, light, and/or applied magnetic field) owing to their specific architecture. Exposure of the hybrid particles to external stimuli led to a systematic and reversible variation in the hydrodynamic diameter (swelling-deswelling) and thus in the optical properties of the hybrid particles (red-shifting of the plasmon band). Such stimuli-responsive volume changes can be effectively exploited in drug-delivery applications.

Bilateral diaphragmatic paralysis associated with the use of the tumor necrosis factor-alpha inhibitor adalimumab.

A 51-year-old woman was referred for evaluation of progressive dyspnea of 3 months- duration. She had received 3 doses of adalimumab for treatment of rheumatoid arthritis prior to the onset of her dyspnea. Her chest examination revealed absent diaphragmatic movement with inspiration. Spirometry showed a severe restrictive defect. Radiologic studies confirmed the diagnosis of bilateral diaphragmatic paralysis. Laboratory and radiologic workup excluded other possible causes of the diagnosis. Adalimumab was discontinued, and she was treated with bilevel positive airway pressure ventilation and intravenous immunoglobulin. Three months later, the diaphragmatic paralysis persisted. This is the second reported case of bilateral diaphragmatic paralysis occurring in a patient who had received adalimumab. Acute neuropathies are rare side effects of tumor necrosis factor-alpha inhibitors.

Down-regulation of the human VEGF gene expression by perylene monoimide derivatives.

The proximal promoter region of the human vascular endothelial growth factor (VEGF) gene contains a guanine-rich strand that can act as a transcriptional silencer by forming an intramolecular G-quadruplex. In this study, we compared two perylene monoimide derivatives, PM1 and PM2, with the well-studied perylene diimide derivative, PIPER, and the well-studied porphyrin derivative, TmPyP(4), with regard to G-quadruplex formation, G-quadruplex binding selectivity, and human VEGF gene silencing in A549 lung cancer cells. The results show that these perylene derivatives can preferentially induce intramolecular G-quadruplex formation from a duplex containing the VEGF G-quadruplex motif in vitro. Incubating A549 lung cancer cells with these perylene derivatives, especially PM2, led to the reduction of both VEGF mRNA and VEGF protein. This study might provide the foundation for the rational design and development of new perylene derivatives as effective anti-angiogenesis agents for cancer therapy.

The influence of pH on the G-quadruplex binding selectivity of perylene derivatives.

Three new perylene derivatives with branched ionizable side chains were synthesized, and their G-quadruplex binding specificities were compared by spectroscopic and electrophoretic analysis with two well-studied G-quadruplex ligands: PIPER and TmPyP4. The value of pH and consequent charge formation and self-aggregation of these perylene derivatives influences not only the type of G-quadruplex formation, but also the G-quadruplex binding selectivity.

The filum terminale externum.

OBJECT: The filum terminale externum (FTE) is the extradural component of the filum terminale internum and little attention has been dedicated to this structure in the literature. The authors theorized that the rare intrasacral ependymomas may originate from ependymal cell collections within the FTE. METHODS: To address this hypothesis, the FTE was dissected and analyzed histologically in 15 adult cadavers. None of the specimens was found to harbor ependymal or other glial cell collections. CONCLUSIONS: The authors found previously undescribed smooth-muscle cells within the FTE. Furthermore, histological analysis identified adipose, nerve, bone, and cartilage cells.