Cells need to sense their mechanical environment during the growth of developing tissues and maintenance of adult tissues. The concept of force-sensing mechanisms that act through cell-cell and ...cell-matrix adhesions is now well established and accepted. Additionally, it is widely believed that force sensing can be mediated through cilia. Yet, this hypothesis is still debated. By using primary cilia sensing as a paradigm, we describe the physical requirements for cilium-mediated mechanical sensing and discuss the different hypotheses of how this could work. We review the different mechanosensitive channels within the cilium, their potential mode of action and their biological implications. In addition, we describe the biological contexts in which cilia are acting - in particular, the left-right organizer - and discuss the challenges to discriminate between cilium-mediated chemosensitivity and mechanosensitivity. Throughout, we provide perspectives on how quantitative analysis and physics-based arguments might help to better understand the biological mechanisms by which cells use cilia to probe their mechanical environment.
Abstract Pulmonary arterial hypertension (PAH) is responsible for the premature death mainly because of progressive and severe heart failure. This disease is characterized by increased pulmonary ...vascular tone, inflammatory cell infiltration, vascular remodeling and occlusion of vessels with thrombi, frequently leading to right heart failure. Aiming to better comprehend the complexity of PAH and find novel therapeutic strategies or improve the existing ones, a variety of preclinical models have emerged. Although there is no ideal preclinical model of PAH currently available, animal models have been used to assist in the identification of the molecular pathways underlying PAH development and progression, and in the identification of novel therapeutics. Among preclinical models of PAH, monocrotaline (MCT) animal model offers the advantage of mimic several key aspects of human PAH, including vascular remodeling, proliferation of smooth muscle cells, endothelial dysfunction, upregulation of inflammatory cytokines, and right ventricle failure, requiring a single drug injection. This review summarizes the advantages and limitations of MCT animal model to the study of the molecular mechanisms underlying PAH pathogenesis, envisioning to improve the diagnosis and management of this complex disease.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The largest monkeypox virus (MPXV) outbreak described so far in non-endemic countries was identified in May 2022 (refs.
). In this study, shotgun metagenomics allowed the rapid reconstruction and ...phylogenomic characterization of the first MPXV outbreak genome sequences, showing that this MPXV belongs to clade 3 and that the outbreak most likely has a single origin. Although 2022 MPXV (lineage B.1) clustered with 2018-2019 cases linked to an endemic country, it segregates in a divergent phylogenetic branch, likely reflecting continuous accelerated evolution. An in-depth mutational analysis suggests the action of host APOBEC3 in viral evolution as well as signs of potential MPXV human adaptation in ongoing microevolution. Our findings also indicate that genome sequencing may provide resolution to track the spread and transmission of this presumably slow-evolving double-stranded DNA virus.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The impact of inhalable fine particulate matter (PM2.5, aerodynamic diameter <2.5 μm) on public health is of great concern worldwide. Knowledge on their harmful effects are mainly due to studies ...carried out with whole air particles, with the contribution of their different fractions remaining largely unknown. Herein, a set of urban PM2.5 samples were collected during daytime and nighttime periods in autumn and spring, aiming to address the seasonal and day-night variability of water-soluble organic matter (WSOM) composition. In vitro analysis of the oxidative and pro-inflammatory potential of WSOM samples was carried out in both acute (24 h) and chronic (3 weeks) exposure setups using Raw264.7 macrophages as cell model. Findings revealed that the structural composition of WSOM samples differs between seasons and in a day–night cycle. Cell exposure resulted in an increase in the transcription of the cytoprotective Hmox1 and pro-inflammatory genes Il1b and Nos2, leading to a moderate pro-inflammatory status. These macrophages showed an impaired capacity to subsequently respond to a strong pro-inflammatory stimulus such as bacterial lipopolysaccharide, which may implicate a compromised capacity to manage harmful pathogens. Further investigation on aerosol WSOM could help to constrain the mechanisms of WSOM-induced respiratory diseases and contribute to PM2.5 regulations.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
The pattern of blood flow has long been thought to play a significant role in vascular morphogenesis, yet the flow-sensing mechanism that is involved at early embryonic stages, when flow forces are ...low, remains unclear. It has been proposed that endothelial cells use primary cilia to sense flow, but this has never been tested in vivo. Here we show, by noninvasive, high-resolution imaging of live zebrafish embryos, that endothelial cilia progressively deflect at the onset of blood flow and that the deflection angle correlates with calcium levels in endothelial cells. We demonstrate that alterations in shear stress, ciliogenesis, or expression of the calcium channel PKD2 impair the endothelial calcium level and both increase and perturb vascular morphogenesis. Altogether, these results demonstrate that endothelial cilia constitute a highly sensitive structure that permits the detection of low shear forces during vascular morphogenesis.
Display omitted
Display omitted
•Endothelial cilia are present during angiogenesis and deflected by low flow forces•Cilia deflection leads to endothelial calcium increase as flow forces increase•Endothelial cilia ultrastructure is unique, which makes it highly flexible•Cilia, flow, and PKD2 are necessary for early angiogenesis
Blood flow is a major mechanical stimulus that controls vascular development, yet the mechanodetection mechanisms that drive angiogenesis are poorly understood. Vermot and colleagues now show that primary cilia located at the endothelial cell surface regulate early angiogenesis. The authors demonstrate that cilia-mediated mechanodetection detects low flow forces through PKD2-mediated calcium fluxes.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
Traditional lab classes in microbiology are common in several educational institutions, which can provide a learning experience disconnected from the myriad of experiments performed in ...research laboratories. Attempting to promote an authentic learning opportunity of the functioning of a bacteriology research laboratory, we developed the “Real-Lab-Day,” a multimodal learning experience to develop competencies, abilities, critical analysis, and teamwork skills for undergraduate students. Students were divided into groups and assigned to research laboratories to be mentored by graduate students, to design and carry out scientific assays. Undergraduate students were introduced to methods such as cellular and molecular assays, flow cytometry, and fluorescence microscopy, as tools to address scientific questions about bacterial pathogenicity, bacterial resistance, and other topics. To consolidate their learning, students created and presented a poster in a rotational panel of peer learning. The perceived learning and interest in microbiology research were improved by the Real-Lab-Day experience, and >95% of the students approved the Real-Lab-Day as a teaching tool in microbiology. Students exposed to a research laboratory had a positive experience with the teaching method, and over 90% saw it as beneficial to improve their understanding of the scientific concepts discussed during lectures. Likewise, their interest in pursuing a career in microbiology was stimulated by the Real-Lab-Day experience. In conclusion, this educational initiative depicts an alternative methodology to connect students to the research and offers an opportunity to be in close contact with experts and graduate students, who gain teaching experience.
The “Real-Lab-Day” is a multimodal learning experience to develop competencies, abilities, critical analysis, and teamwork skills for undergraduate students.
Bacillus subtilis endospores have applications in different fields including their use as probiotics and antigen delivery vectors. Such specialized applications frequently require highly purified ...spore preparations. Nonetheless, quantitative data regarding both yields and purity of B. subtilis endospores after application of different growth conditions and purification methods are scarce or poorly reported. In the present study, we conducted several quantitative and qualitative analyses of growth conditions and purification procedures aiming generation of purified B. subtilis spores. Based on two growth media and different incubations conditions, sporulation frequencies up to 74.2 % and spore concentrations up to 7 × 10⁹ spores/ml were achieved. Application of a simplified spore isolation method, in which samples were incubated with lysozyme and a detergent, resulted in preparations with highly purified spores at the highest yields. The present study represents, therefore, an important contribution for those working with B. subtilis endospores for different biotechnological purposes.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Cancer-induced cardiac cachexia is an insidious syndrome with a dramatic impact on a patient’s quality of life and survival. Since exercise training provides several cardiovascular benefits in both ...physiological and pathological conditions (e.g., athletes and patients with heart failure, respectively), its use as a preventive and/or therapeutic tool for cancer-induced cardiac cachexia has been hypothesized. Existing evidence on the effects of exercise training in this particular setting is limited, but points towards a beneficial outcome. We report the current knowledge on cancer-induced cardiac cachexia and discuss the molecular pathways that may be modulated by exercise training in this setting, providing insights into possible future roads of study, namely in stem cell research and cardiac regeneration.
Cancer-induced cardiac cachexia is an insidious syndrome that may occur independently of cardiotoxic chemotherapy.
Exercise training modulates several molecular pathways involved in cardiac hypertrophy, regeneration, and metabolism, in both physiological and pathological conditions.
Preclinical data support the notion that exercise training prevents and reverts the cardiac remodeling suffered during cancer-induced cardiac cachexia, potentially by modulating tumoral activity, inflammation, metabolism, and fibrosis.
Exercise training presents itself as a promising therapy and/or adjuvant in cancer-induced cardiac cachexia.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Bacillus subtilis spores have been used as safe and heat-resistant antigen delivery vectors. Nonetheless, the oral administration of spores typically induces weak immune responses to the passenger ...antigens, which may be attributed to the fast transit through the gastrointestinal tract. To overcome this limitation, we have developed B. subtilis spores capable of binding to the gut epithelium by means of expressing bacterial adhesins on the spore surface. The resulting spores bound to in vitro intestinal cells, showed a longer transit through the mouse intestinal tract, and interacted with Peyer's patch cells. The adhesive spores increased the systemic and secreted antibody responses to the Streptococcus mutans P1 protein, used as a model antigen, following oral, intranasal, and sublingual administration. Additionally, P1-specific antibodies efficiently inhibited the adhesion of the oral pathogen Streptococcus mutans to abiotic surfaces. These results support the use of gut-colonizing B. subtilis spores as a new platform for the mucosal delivery of vaccine antigens.
Food enzymes are used for technical purposes in the production of food ingredients or foods‐as‐consumed. In the European Union, the safety of a food enzyme is evaluated by EFSA on the basis of a ...technical dossier provided by an applicant. Dietary exposure is an integral part of the risk assessment of food enzymes. To develop exposure models specific to each food manufacturing process in which food enzymes are used, different input data are required which are then used in tandem with technical conversion factors. This allows the use levels of food enzyme to be related to food consumption data collected in dietary surveys. For each food manufacturing process, EFSA identified a list of food groups (FoodEx1 classification system) and collated technical conversion factors. To ensure a correct and uniform application of these input data in the assessment of food enzyme dossiers, stakeholders were consulted via open calls‐for‐data. In addition to publishing and updating the identified input parameters on an annual basis, single‐process‐specific calculators of the Food Enzyme Intake Models (FEIMs) have been developed. These calculators have been deposited at https://zenodo.org/ since 2018 for open access. By 2023, EFSA had compiled the input data for a total of 40 food manufacturing processes in which food enzymes are employed. In this document, the food manufacturing processes are structured, food groups classified initially in the FoodEx1 system are translated into the FoodEx2 system, and technical factors are adjusted to reflect the more detailed and standardised FoodEx2 nomenclature. The development of an integrated FEIM‐web tool using this collection of input data is carried out for a possible release in 2024. This tool will be able to estimate the exposure to the food enzyme–total organic solids (TOS) when employed in multiple food manufacturing processes.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
PDF
