Transcultural body spaces: re-inventing and performing headwrap practice among young Congolese women in London

This article examines embodied representation of race, ethnicity, and gender, questioning ideas of cultural appropriation. Using the London-based Congolese transnational fashion brand Kiyana Wraps as a case study, the article addresses how young Congolese designers re-invent their cultural heritage to conceive the label stylisation and construct meanings of Blackness/Africanness. The article also explores the brand’s social spaces, where the headwrap ritual is used by different actors to perform hybrid identities. In addition, wearing the headwrap reveals symbolic metaphors of empowerment, through which intertwined ‘feminist’ and ‘feminine’ identities are evoked. The paper examines how Congolese women are creatively taking inspiration from the environment of London to produce innovative fashion trajectories as lived socio-cultural experiences. It argues how the headwrap ritual signifies an aesthetic and material process through which specific racial and ethnic boundaries are transcended, fabricating transcultural body spaces which encompass individuals with diverse cultural backgrounds

The common HAQ STING variant impairs cGAS-dependent antibacterial responses and is associated with susceptibility to Legionnaires’ disease in humans

Abstract The cyclic GMP-AMP synthase (cGAS)-STING pathway is central for innate immune sensing of various bacterial, viral and protozoal infections. Recent studies identified the common HAQ and R232H alleles of TMEM173/STING, but the functional consequences of these variants for primary infections are unknown. Here we demonstrate that cGAS- and STING-deficient murine macrophages as well as human cells of individuals carrying HAQ TMEM173/STING were severely impaired in producing type I IFNs and pro-inflammatory cytokines in response to Legionella pneumophila, bacterial DNA or cyclic dinucleotides (CDNs). In contrast, R232H attenuated cytokine production only following stimulation with bacterial CDN, but not in response to L. pneumophila or DNA. In a mouse model of Legionnaires’ disease, cGAS- and STING-deficient animals exhibited higher bacterial loads as compared to wild-type mice. Moreover, the haplotype frequency of HAQ TMEM173/STING, but not of R232H TMEM173/STING, was increased in two independent cohorts of human Legionnaires’ disease patients as compared to healthy controls. Our study reveals that the cGAS-STING cascade contributes to antibacterial defense against L. pneumophila in mice and men, and provides important insight into how the common HAQ TMEM173/STING variant affects antimicrobial immune responses and susceptibility to infection. Trial registration ClinicalTrials.gov DRKS00005274, German Clinical Trials Register Author summary Interferons (IFNs) and pro-inflammatory cytokines are key regulators of gene expression and antibacterial defense during Legionella pneumophila infection. Here we demonstrate that production of these mediators was largely or partly dependent on the cyclic GMP-AMP synthase (cGAS)-STING pathway in human and murine cells. Cells of individuals carrying the common HAQ allele of TMEM173/STING were strongly impaired in their ability to respond to L. pneumophila, bacterial DNA or cyclic dinucleotides (CDNs), whereas the R232H allele was only attenuated in sensing of exogenous CDNs. Importantly, cGAS and STING contributed to antibacterial defense in mice during L. pneumophila lung infection, and the allele frequency of HAQ TMEM173/STING, but not of R232H TMEM173/STING, was increased in two independent cohorts of human Legionnaires’ disease patients as compared to healthy controls. Hence, sensing of bacterial DNA by the cGAS/STING pathway contributes to antibacterial defense against L. pneumophila infection, and the hypomorphic variant HAQ TMEM173/STING is associated with increased susceptibility to Legionnaires’ disease in humans

Embryonic stem cells in scaffold-free three-dimensional cell culture: osteogenic differentiation and bone generation

Extracorporeal formation of mineralized bone-like tissue is still an unsolved challenge in tissue engineering. Embryonic stem cells may open up new therapeutic options for the future and should be an interesting model for the analysis of fetal organogenesis. Here we describe a technique for culturing embryonic stem cells (ESCs) in the absence of artificial scaffolds which generated mineralized miromasses. Embryonic stem cells were harvested and osteogenic differentiation was stimulated by the addition of dexamethasone, ascorbic acid, and ß-glycerolphosphate (DAG). After three days of cultivation microspheres were formed. These spherical three-dimensional cell units showed a peripheral zone consisting of densely packed cell layers surrounded by minerals that were embedded in the extracellular matrix. Alizarine red staining confirmed evidence of mineralization after 10 days of DAG stimulation in the stimulated but not in the control group. Transmission electron microscopy demonstrated scorching crystallites and collagenous fibrils as early indication of bone formation. These extracellular structures resembled hydroxyl apatite-like crystals as demonstrated by distinct diffraction patterns using electron diffraction analysis. The micromass culture technique is an appropriate model to form three-dimensional bone-like micro-units without the need for an underlying scaffold. Further studies will have to show whether the technique is applicable also to pluripotent stem cells of different origin

Osseointegration of zirconia implants: an SEM observation of the bone-implant interface

Background The successful use of zirconia ceramics in orthopedic surgery led to a demand for dental zirconium-based implant systems. Because of its excellent biomechanical characteristics, biocompatibility, and bright tooth-like color, zirconia (zirconium dioxide, ZrO2) has the potential to become a substitute for titanium as dental implant material. The present study aimed at investigating the osseointegration of zirconia implants with modified ablative surface at an ultrastructural level. Methods A total of 24 zirconia implants with modified ablative surfaces and 24 titanium implants all of similar shape and surface structure were inserted into the tibia of 12 Gottinger minipigs. Block biopsies were harvested 1 week, 4 weeks or 12 weeks (four animals each) after surgery. Scanning electron microscopy (SEM) analysis was performed at the bone implant interface. Results Remarkable bone attachment was already seen after 1 week which increased further to intimate bone contact after 4 weeks, observed on both zirconia and titanium implant surfaces. After 12 weeks, osseointegration without interposition of an interfacial layer was detected. At the ultrastructural level, there was no obvious difference between the osseointegration of zirconia implants with modified ablative surfaces and titanium implants with a similar surface topography. Conclusion The results of this study indicate similar osseointegration of zirconia and titanium implants at the ultrastructural level