Broekudsk5480
Large oligomeric enzymes control a myriad of cellular processes, from protein synthesis and degradation to metabolism. The 0.5 MDa large TET2 aminopeptidase, a prototypical protease important for cellular homeostasis, degrades peptides within a ca. 60 Å wide tetrahedral chamber with four lateral openings. The mechanisms of substrate trafficking and processing remain debated. Here, we integrate magic-angle spinning (MAS) NMR, mutagenesis, co-evolution analysis and molecular dynamics simulations and reveal that a loop in the catalytic chamber is a key element for enzymatic function. The loop is able to stabilize ligands in the active site and may additionally have a direct role in activating the catalytic water molecule whereby a conserved histidine plays a key role. Our data provide a strong case for the functional importance of highly dynamic - and often overlooked - parts of an enzyme, and the potential of MAS NMR to investigate their dynamics at atomic resolution.
Endoplasmic reticulum (ER) stress is involved in the pathological process of pulmonary fibrosis, including IPF. It affects a broad scope of cellular types during pulmonary fibrosis but the role in epithelial-mesenchymal crosstalk has not been fully defined. The present study aimed to investigate the effects of Shh secretion by ER stress-challenged type II alveolar epithelial cells (AECII) on fibroblast and pulmonary fibrosis.
Conditioned medium (CM) from tunicamycin (TM)-treated AECII was collected and incubated with fibroblast. Short hairpin RNA (shRNA) was used for RNA interference of C/EBP homologous protein (CHOP). The effects of CHOP and HH signaling were evaluated by TM administration under the background of bleomycin-induced pulmonary fibrosis in mice.
Both expression of CHOP and Shh in AECII, and HH signaling in mesenchyme were upregulated in IPF lung. TM-induced Shh secretion from AECII activates HH signaling andpromotes pro-fibrotic effects of fibroblast. Interfering CHOP expression reduced ER stress-induced Shh secretion and alleviated pulmonary fibrosis in mice.
Our work identified a novel mechanism by which ER stress is involved in pulmonary fibrosis. Inhibition of ER stress or CHOP in epithelial cells alleviated pulmonary fibrosis by suppressing Shh/HH signaling pathway of fibroblasts.
Our work identified a novel mechanism by which ER stress is involved in pulmonary fibrosis. Inhibition of ER stress or CHOP in epithelial cells alleviated pulmonary fibrosis by suppressing Shh/HH signaling pathway of fibroblasts.
This study was performed to evaluate the rebound phenomenon after the correction of coronal angular deformity by hemiepiphysiodesis using tension band plate in children and to identify its risk factors.
We reviewed 50 children (mean age, 11.0 ± 2.5 years) with 94 physes who had undergone hemiepiphysiodesis using tension band plate due to coronal angular deformity of the lower limb. Patients' demographic data including sex, age at initial surgery and plate removal, affected bone (distal femur or proximal tibia), affected side, and body mass index were collected. The mechanical lateral distal femoral angle (mLDFA) and the mechanical medial proximal tibial angle (mMPTA) were measured from the teleradiogram, Physes were divided into rebound and non-rebound group, and rebound group was defined as the physes which had ≥ 5° of mLDFA or mMPTA returning to its original deformity. Generalized estimating equation based multivariable analysis was used to identify the risk factors for the rebound phenomenon after thudy showed that the rebound group had younger age and faster correction rate than those in the non-rebound group. In addition, the correction rate for deformity was a significant risk factor for the rebound phenomenon after hemiepiphysiodesis using the tension band plate. Close monitoring after implant removal is required for children who have a rapid correction rate over 7°/year.The cytokine IFNγ differentially impacts on tumors upon immune checkpoint blockade (ICB). Despite our understanding of downstream signaling events, less is known about regulation of its receptor (IFNγ-R1). With an unbiased genome-wide CRISPR/Cas9 screen for critical regulators of IFNγ-R1 cell surface abundance, we identify STUB1 as an E3 ubiquitin ligase for IFNγ-R1 in complex with its signal-relaying kinase JAK1. STUB1 mediates ubiquitination-dependent proteasomal degradation of IFNγ-R1/JAK1 complex through IFNγ-R1K285 and JAK1K249. Conversely, STUB1 inactivation amplifies IFNγ signaling, sensitizing tumor cells to cytotoxic T cells in vitro. This is corroborated by an anticorrelation between STUB1 expression and IFNγ response in ICB-treated patients. Consistent with the context-dependent effects of IFNγ in vivo, anti-PD-1 response is increased in heterogenous tumors comprising both wildtype and STUB1-deficient cells, but not full STUB1 knockout tumors. These results uncover STUB1 as a critical regulator of IFNγ-R1, and highlight the context-dependency of STUB1-regulated IFNγ signaling for ICB outcome.
Incidence of stroke is increasing in sub-Saharan Africa. People who survive stroke experience disability and require long-term care. Health systems in South Africa (SA) are experiencing important challenges, and services in the public health system for people with stroke (PWS) are fragmented. Ceftaroline cell line We aimed to explore the perspectives and experiences of PWS related to stroke care services to inform health system strengthening measures.
In-depth interviews with 16 PWS in urban and rural areas in the Western and Eastern Cape Provinces of SA were conducted between August and October 2020. PWS were recruited through existing research networks, non-government organisations and organisations of persons with disabilities by snowball sampling. Interviews were transcribed, coded, and thematically analysed. We used the conceptual framework of access to health care as proposed by Levesque et al. to map and inform barriers to accessing health care from the user perspective.
PWS recognised the need for health care when thd services to patients and their social support network. The role of family members in continuity of care could be strengthened by raising awareness of existing resources and referral pathways, and facilitating connections within services.
Strategic leadership, governance and better resources at multiple levels are required to address the unmet demands and needs for health care of PWS. Stroke care could be strengthened by service providers routinely providing information about prevention and symptoms of stroke, treatment, and services to patients and their social support network. The role of family members in continuity of care could be strengthened by raising awareness of existing resources and referral pathways, and facilitating connections within services.
External fixation, which can preserve the biomechanical microenvironment of fracture healing, plays an important role in managing the high-energy fractures with poor surrounding soft tissues. The purpose of this study was to determine the differences of clinical outcomes, if any, between hexapod external fixator and monolateral external fixator in the definitive treatment of high-energy tibial diaphyseal fractures.
A total of 53 patients with high-energy tibial diaphyseal fractures and definitively treated by the hexapod external fixator (HEF) or monolateral external fixator (MEF) were retrospectively collected and analyzed, from March 2015 to June 2019. There were 31 patients in the HEF treatment, and the other 22 patients were managed by the MEF. The demographic data, surgical duration, external fixation time, final radiological results, complications, and clinical outcomes were documented and analyzed. Difficulties that occurred during the treatment were classified according to Paley. The clinical outcinitive treatment of high-energy tibial diaphyseal fractures. The hexapod external fixation treatment is a superior effective method, including advantages of stable fixation, less surgical duration, postoperatively satisfactory fracture reduction, and fewer complications.
There is no statistically significant difference in finally clinical outcomes between hexapod external fixator and monolateral external fixator in the definitive treatment of high-energy tibial diaphyseal fractures. The hexapod external fixation treatment is a superior effective method, including advantages of stable fixation, less surgical duration, postoperatively satisfactory fracture reduction, and fewer complications.Terrestrial evaporation (E) is a key climatic variable that is controlled by a plethora of environmental factors. The constraints that modulate the evaporation from plant leaves (or transpiration, Et) are particularly complex, yet are often assumed to interact linearly in global models due to our limited knowledge based on local studies. Here, we train deep learning algorithms using eddy covariance and sap flow data together with satellite observations, aiming to model transpiration stress (St), i.e., the reduction of Et from its theoretical maximum. Then, we embed the new St formulation within a process-based model of E to yield a global hybrid E model. In this hybrid model, the St formulation is bidirectionally coupled to the host model at daily timescales. Comparisons against in situ data and satellite-based proxies demonstrate an enhanced ability to estimate St and E globally. The proposed framework may be extended to improve the estimation of E in Earth System Models and enhance our understanding of this crucial climatic variable.
The pathogenesis of chronic thromboembolic pulmonary hypertension (CTEPH) is considered to be associated with chronic inflammation; however, the underlying mechanism remains unclear. Recently, altered gut microbiota were found in patients with pulmonary arterial hypertension (PAH) and in experimental PAH models. The aim of this study was to characterize the gut microbiota in patients with CTEPH and assess the relationship between gut dysbiosis and inflammation in CTEPH.
In this observational study, fecal samples were collected from 11 patients with CTEPH and 22 healthy participants. The abundance of gut microbiota in these fecal samples was assessed using 16S ribosomal ribonucleic acid (rRNA) gene sequencing. Inflammatory cytokine and endotoxin levels were also assessed in patients with CTEPH and control participants.
The levels of serum tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-8, and macrophage inflammatory protein (MIP)-1α were elevated in patients with CTEPH. Plasma endotoxin levels were significantly increased in patients with CTEPH (P < 0.001), and were positively correlated with TNF-α, IL-6, IL-8, and MIP-1α levels. The 16S rRNA gene sequencing and the principal coordinate analysis revealed the distinction in the gut microbiota between patients with CTEPH (P < 0.01) and control participants as well as the decreased bacterial alpha-diversity in patients with CTEPH. A random forest analysis for predicting the distinction in gut microbiota revealed an accuracy of 80.3%.
The composition of the gut microbiota in patients with CTEPH was distinct from that of healthy participants, which may be associated with the elevated inflammatory cytokines and endotoxins in CTEPH.
The composition of the gut microbiota in patients with CTEPH was distinct from that of healthy participants, which may be associated with the elevated inflammatory cytokines and endotoxins in CTEPH.