108 research outputs found
Topography-driven alterations in endothelial cell phenotype and contact guidance
Bioengineering; Biophysics; Cell biology; Biomedical engineering; Regenerative medicine; Directional topography; Endothelial cells; Vascular-like networks; Contact guidance; Vascularizatio
Topography-Mediated Myotube and Endothelial Alignment, Differentiation, and Extracellular Matrix Organization for Skeletal Muscle Engineering
Understanding the response of endothelial cells to aligned myotubes is important to create an appropriate environment for tissue-engineered vascularized skeletal muscle. Part of the native tissue environment is the extracellular matrix (ECM). The ECM is a supportive scaffold for cells and allows cellular processes such as proliferation, differentiation, and migration. Interstitial matrix and basal membrane both comprise proteinaceous and polysaccharide components for strength, architecture, and volume retention. Virtually all cells are anchored to their basal lamina. One of the physical factors that affects cell behavior is topography, which plays an important role on cell alignment. We tested the hypothesis that topography-driven aligned human myotubes promote and support vascular network formation as a prelude to in vitro engineered vascularized skeletal muscle. Therefore, we used a PDMS-based topography substrate to investigate the influence of pre-aligned myotubes on the network formation of microvascular endothelial cells. The aligned myotubes produced a network of collagen fibers and laminin. This network supported early stages of endothelial network formation.</p
The mucosal adjuvant cholera toxin B instructs non-mucosal dendritic cells to promote IgA production via retinoic acid and TGF-β
It is currently unknown how mucosal adjuvants cause induction of secretory immunoglobulin A (IgA), and how T cell-dependent (TD) or -independent (TI) pathways might be involved. Mucosal dendritic cells (DCs) are the primary antigen presenting cells driving TI IgA synthesis, by producing a proliferation-inducing ligand (APRIL), B cell activating factor (BAFF), Retinoic Acid (RA), TGF-beta or nitric oxide (NO). We hypothesized that the mucosal adjuvant Cholera Toxin subunit B (CTB) could imprint non-mucosal DCs to induce IgA synthesis, and studied the mechanism of its induction. In vitro, CTB-treated bone marrow derived DCs primed for IgA production by B cells without the help of T cells, yet required co-signaling by different Toll-like receptor (TLR) ligands acting via the MyD88 pathway. CTB-DC induced IgA production was blocked in vitro or in vivo when RA receptor antagonist, TGF-beta signaling inhibitor or neutralizing anti-TGF-beta was added, demonstrating the involvement of RA and TGF-beta in promoting IgA responses. There was no major involvement for BAFF, APRIL or NO. This study highlights that synergism between CTB and MyD88-dependent TLR signals selectively imprints a TI IgA-inducing capacity in non-mucosal DCs, explaining how CTB acts as an IgA promoting adjuvant
Change in Androgenic Status and Cardiometabolic Profile of Middle-Aged Women with Polycystic Ovary Syndrome
Understanding the cardiovascular disease (CVD) risk for women with polycystic ovary syndrome (PCOS) at reproductive age is crucial. To investigate this, we compared the cardiometabolic profiles of different PCOS groups over a median interval of 15.8 years. The study focused on three groups: (1) women with PCOS who were hyperandrogenic at both initial and follow-up screening (HA-HA), (2) those who transitioned from hyperandrogenic to normoandrogenic (HA-NA), and (3) those who remained normoandrogenic (NA-NA). At initial and follow-up screenings, both HA-HA and HA-NA groups showed higher body mass indexes compared to the NA-NA group. Additionally, at follow-up, the HA-HA and HA-NA groups exhibited higher blood pressure, a higher prevalence of hypertension, elevated serum triglycerides and insulin levels, and lower levels of HDL cholesterol compared to the NA-NA group. Even after adjusting for BMI, significant differences persisted in HDL cholesterol levels and hypertension prevalence among the groups (HA-HA: 53.8%, HA-NA: 53.1%, NA-NA: 14.3%, p < 0.01). However, calcium scores and the prevalence of coronary plaques on CT scans were similar across all groups. In conclusion, women with PCOS and hyperandrogenism during their reproductive years exhibited an unfavorable cardiometabolic profile during their post-reproductive years, even if they changed to a normoandrogenic status.</p
Omega-1, a glycoprotein secreted by Schistosoma mansoni eggs, drives Th2 responses
Soluble egg antigens of the parasitic helminth Schistosoma mansoni (S. mansoni egg antigen [SEA]) induce strong Th2 responses both in vitro and in vivo. However, the specific molecules that prime the development of Th2 responses have not been identified. We report that omega-1, a glycoprotein which is secreted from S. mansoni eggs and present in SEA, is capable of conditioning human monocyte-derived dendritic cells in vitro to drive T helper 2 (Th2) polarization with similar characteristics as whole SEA. Furthermore, using IL-4 dual reporter mice, we show that both natural and recombinant omega-1 alone are sufficient to generate Th2 responses in vivo, even in the absence of IL-4R signaling. Finally, omega-1–depleted SEA displays an impaired capacity for Th2 priming in vitro, but not in vivo, suggesting the existence of additional factors within SEA that can compensate for the omega-1–mediated effects. Collectively, we identify omega-1, a single component of SEA, as a potent inducer of Th2 responses
Incidental findings on coronary computed tomography in women with selected reproductive disorders
OBJECTIVE: To determine the prevalence of incidental findings (IFs) on coronary computed tomography (CCT) in women aged 45–55 years and previously diagnosed with reproductive disorders such as polycystic ovary syndrome (PCOS), premature ovarian insufficiency (POI) or preeclampsia (PE). METHODS: A total of 486 middle-aged women with PCOS (n = 101), POI (n = 97) or a history of PE (n = 288) underwent a CCT as part of a prior prospective study. IFs were categorized by their significance (minor, moderate and major). Follow-up information was collected from patients’ records. To investigate the impact of different field of views (FOVs), a subset of scans was analyzed in full FOV and small FOV. RESULTS: In 96/486 (19.8%) women, one or more IFs were detected, of which 54/486 (11.1%) were classified as moderate/major and 48/486 (9.9%) required follow-up. A moderate/major IF was detected in 16/101 (15.9%) women with PCOS, 13/97 (13.4%) women with POI and 25/288 (8.7%) women with a history of PE. In 78 women with an IF detected in the full FOV, the IF was still visible in 60 (76.9%) women in the small FOV. In the full FOV, 46 women required follow-up, but using the small FOV this was reduced to 30 women. CONCLUSION: Using CCT as a cardiovascular disease screening tool in women with selected reproductive disorders increases the probability of detecting IFs that can cause anxiety and may generate extra costs, but can also reveal clinically relevant findings. Using a small FOV centered around the heart resulted in a lower prevalence of IFs and required less follow-up
Femtosecond laser and microkeratome-assisted Descemet stripping endothelial keratoplasty: first clinical results
Pro-inflammatory activation following demyelination is required for myelin clearance and oligodendrogenesis
Remyelination requires innate immune system function, but how exactly microglia and macrophages clear myelin debris after injury and tailor a specific regenerative response is unclear. Here, we asked whether pro-inflammatory microglial/macrophage activation is required for this process. We established a novel toxin-based spinal cord model of de- and remyelination in zebrafish and showed that pro-inflammatory NF-κB-dependent activation in phagocytes occurs rapidly after myelin injury. We found that the pro-inflammatory response depends on myeloid differentiation primary response 88 (MyD88). MyD88-deficient mice and zebrafish were not only impaired in the degradation of myelin debris, but also in initiating the generation of new oligodendrocytes for myelin repair. We identified reduced generation of TNF-α in lesions of MyD88-deficient animals, a pro-inflammatory molecule that was able to induce the generation of new premyelinating oligodendrocytes. Our study shows that pro-inflammatory phagocytic signaling is required for myelin debris degradation, for inflammation resolution, and for initiating the generation of new oligodendrocytes
Trabecular bone density in middle-aged women with reproductive disorders
Besides age, estrogen exposure plays a crucial role in changes in bone density (BD) in women. Premature ovarian insufficiency (POI) and polycystic ovary syndrome (PCOS) are conditions in reproductive-aged women in which the exposure to estrogen is substantially different. Women with a history of preeclampsia (P E) are expected to have normal estrogen exposure. Within the CREw IMAGO study, we investigated if trabecular BD is different in these women because of differences in the duration of estrogen exposure. Trabecular BD was measured in thoracic vertebrae on coronary CT scans. Women with a reduced estrogen exposure (POI) have a lower BD compared to women with an intermediate exposure (PE) (mean difference (MD) −26.8, 95% CI −37.2 to −16.3). Women with a prolonged estrogen exposure (PCOS) have the highest BD (MD 15.0, 95% CI 4.3–25.7). These results support the hypothesis that the duration of estrogen exposure in these women is associated with trabecular BD.
Significance statement: Our results suggest that middle-aged women with PCOS have a higher BD and women with POI have a lower BD. We hypothesized that this is due to either a prolonged estrogen exposure, as seen in women with PCOS, or a reduced estrogen exposure, as in women with POI. In the counseling of women with reproductive disorders on long-term health issues, coronary CT provides a unique opportunity to assess both coronary artery calcium score for cardiovascular screening as w ell as trabecular BD
A global analysis of the impact of COVID-19 stay-at-home restrictions on crime
The implementation of COVID-19 stay-at-home policies was associated with a considerable drop in urban crime in 27 cities across 23 countries. More stringent restrictions over movement in public space were predictive of larger declines in crime. The stay-at-home restrictions to control the spread of COVID-19 led to unparalleled sudden change in daily life, but it is unclear how they affected urban crime globally. We collected data on daily counts of crime in 27 cities across 23 countries in the Americas, Europe, the Middle East and Asia. We conducted interrupted time series analyses to assess the impact of stay-at-home restrictions on different types of crime in each city. Our findings show that the stay-at-home policies were associated with a considerable drop in urban crime, but with substantial variation across cities and types of crime. Meta-regression results showed that more stringent restrictions over movement in public space were predictive of larger declines in crime.Peer reviewe
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