Search

Abstract Background Airway basal stem cells (ABSCs) have self-renewal and differentiation abilities. Although an abnormal mechanical environment related to chronic airway disease (CAD) can cause ABSC dysfunction, it remains unclear how mechanical stretch regulates the behavior and structure of ABSCs. Here, we explored the effect of mechanical stretch on primary human ABSCs. Methods Primary human ABSCs were isolated from healthy volunteers. A Flexcell FX-5000 Tension system was used to mimic the pathological airway mechanical stretch conditions of patients with CAD. ABSCs were stretched for 12, 24, or 48 h with 20% elongation. We first performed bulk RNA sequencing to identify the most predominantly changed genes and pathways. Next, apoptosis of stretched ABSCs was detected with Annexin V-FITC/PI staining and a caspase 3 activity assay. Proliferation of stretched ABSCs was assessed by measuring MKI67 mRNA expression and cell cycle dynamics. Immunofluorescence and hematoxylin-eosin staining were used to demonstrate the differentiation state of ABSCs at the air-liquid interface. Results Compared with unstretched control cells, apoptosis and caspase 3 activation of ABSCs stretched for 48 h were significantly increased (p

Abstract Besides genetic alterations, the cellular environment also determines disease onset and progression. When different cell types contribute to disease outcome, this imposes environmental challenges as different cell types likely differ in their extracellular dependencies. Hsa‐microRNA‐31‐5p (miR‐31) is highly expressed in keratinocytes of psoriatic skin, and we show that expression in keratinocytes is induced by limited glucose availability and enables increased survival under limiting glucose conditions by increasing glutamine metabolism. In addition, miR‐31 expression results in not only secretion of specific metabolites (aspartate and glutamate) but also secretion of immunomodulatory factors. We show that this miR‐31‐induced secretory phenotype is sufficient to induce Th17 cell differentiation, a hallmark of psoriasis. Inhibitors of miR31‐induced metabolic rewiring and metabolic crosstalk with immune cells alleviate psoriasis pathology in a mouse model of psoriasis. Together our data illustrate an emerging concept of metabolic interaction across cell compartments that characterizes disease development, which can be employed to design effective treatment options for disease, as shown here for psoriasis.

Nowadays, the prognostic prediction of acute ischemic stroke (AIS) patients is still challenging because of the limited predictive properties of existing models. Blood-based biomarkers may provide additional information to the established prognostic factors. Markers of atherosclerosis have been identified as one of the most promising biomarkers for predicting prognosis, and inflammation, in turn, affects atherosclerosis. According to previous studies, the ratio of monocytes to lymphocytes (MLR) has been reported as a novel indicator of inflammation. Thus, our study was the first to conduct more in-depth research on the relationship between MLR and the prognosis of large artery atherosclerosis (LAA)-type AIS patients.A total of 296 patients with LAA-type stroke were recruited. Of these, 202 patients were assigned to the development cohort, and 94 patients were assigned to the validation cohort. In the development cohort, 202 patients were divided into groups A, B, C, and D according to the quartile method of MLR levels. The one-year prognosis of patients was tracked, and the modified Rankin scale (MRS, with a score ranging from 0 to 6) was mainly selected as the measurement result of the function. The relationship between MLR and prognosis was analyzed by building logistics regression models. The models showed that MLR made significant predictions in poor outcomes of LAA-type stroke patients (odds ratio: 4.037; p = 0.048). At the same time, receiver operating characteristics (ROC) curves were used to compare the predictive values between MLR and clinical prediction score (Barthel Index).This study demonstrated that patients with LAA-type stroke and high MLR had a poor prognosis. MLR might be a reliable, inexpensive, and novel predictor of LAA-type stroke prognosis.

The modern coast of China is characterized by complicated hydrology, which might be a potential factor shaping genetic structure of marine organisms. Tridentiger barbatus is a widespread benthic goby in coastal China whose range expansion might depend on larval dispersal in its spawning season. We explored the genetic structure of T. barbatus and its interrelationships with coastal currents, planktonic larval duration, and Pleistocene climate fluctuations. Genealogies of Cytb, Rh, and RAG1 reveal two lineages in T. barbatus, namely the southern and northern lineages. The southern lineage is distributed through the South China Sea to the South Yellow Sea but is absent from the North Yellow Sea and Bohai Sea. The HYCOM average flow field indicates an eddy between the North and South Yellow Seas, which might cause larval retention and limit dispersal of the southern lineage into the North Yellow Sea and the Bohai Sea. The northern lineage is distributed through the South Yellow Sea to the Bohai Sea but is absent from the South China Sea and East China Sea. The distribution of the northern lineage fits the eastward deflection of the Yellow Sea Coastal Current at the boundary of the East China Sea and South Yellow Sea, which might limit southward larval dispersal of the northern lineage into the East China Sea. We also uncovered two Cytb haplotype groups within the southern lineage, namely groups A and B, whose distributions might be shaped by the northward Taiwan Strait Current. The coincidence between the genetic structure of T. barbatus and the coastal currents and eddies strongly implies significant roles of larval dispersal and current transportation in shaping the genetic structure of T. barbatus. In addition, significant isolation by distance is found in the southern lineage, which coincides with its short planktonic larval duration (20–30 days). The inference on divergence time suggests that the observed lineages and haplotype groups in T. barbatus originated in the Pleistocene glaciations. Therefore, the coastal currents, planktonic larval duration, and historical glacial isolation are proposed as important factors shaping the genetic structure of T. barbatus.

CO2 released from subduction zones plays a vital role in the tectonic carbon cycle. However, the contribution of submarine backarc components to carbon emissions remains poorly understood compared to subaerial arc volcanos. This study utilized a combination of geochemical and hydrodynamic approaches to investigate the sources and flux of dissolved inorganic carbon (DIC) in the deep basin of the southwestern Okinawa Trough. Most deep‐water (depth ≥1,000 m) samples, even those retrieved from sites distant from active venting, exhibited mild geochemical anomalies of elevated 3He/4He ratios and higher DIC content than reference sites. Hydrodynamic observations using bottom‐mounted acoustic instruments in the deep basin revealed strong tidal currents and enhanced turbulent mixing. These findings suggest that active solute dispersal and mixing are responsible for the prevalence of mild geochemical anomalies in the basin. Mixing models indicated that hydrothermal vent fluids are the primary source of excess 3He and DIC above background levels in the deep basin, whereas both CO2 and mineral acid in hydrothermal fluids cause excess acidity. Based on hydrodynamic and geochemical data, a box model estimated a hydrothermal DIC flux of 0.62 ± 1.40 × 1010 mol y−1, equivalent to 40% of CO2 emissions from persistently degassing volcanos in the Ryukyu Arc. Our results suggest that submarine carbon emissions are quantitatively important in subduction systems with subaqueous backarc components. Plain Language Summary: The CO2 released from subduction zones, where tectonic plates collide, is important for the Earth's carbon cycle. However, we know little about CO2 released from submarine backarc basins compared to volcanoes on land. This study examined dissolved inorganic carbon (DIC) sources and quantities released into the deep basin of the southwestern Okinawa Trough. Even far from active hydrothermal vents, deep‐water samples had higher DIC levels than expected. Using instruments placed on the seabed, we discovered strong tidal currents and increased water mixing in the basin. These findings suggest that water movement and mixing contribute to the widespread occurrence of elevated DIC levels. Our calculations show that the primary source of the extra DIC in the deep basin is fluids released from hydrothermal vents, and both CO2 and mineral acid cause excess acidity in the water. Based on our data, we estimate that hydrothermal vents release approximately 6 billion moles of DIC per year, equivalent to 40% of the CO2 emissions from continuously active volcanoes in the Ryukyu Arc. These results demonstrate the potential significance of underwater carbon emissions in submerged backarc basins within subduction zones. Key Points: Mild geochemical anomalies in 3He and dissolved inorganic carbon were widespread in the southwestern Okinawa Trough deep waterMixing models confirmed that hot vent fluids are the primary source of excess dissolved inorganic carbon in the deep waterThe carbon outgassing flux of the Ryukyu subduction system increases by at least 27% when the backarc contribution is considered [ABSTRACT FROM AUTHOR]

To ameliorate soil oxygen deficiencies around subsurface drip irrigation (SDI) drippers, aerated irrigation (AI) was introduced to supply aerated water to the soil through venturi installed in the SDI pipeline. The objectives of this study were to assess the effects of AI on soil respiration (SR), air-filled porosity (AFP), soil temperature (ST), and oxygen concentrations (OCC). Total soil respiration (TSR), biological activity temperature index (BAT), and soil oxygen consumption (OCS) based on SR, ST, and OCC, respectively, were subsequently calculated to explore the relationships between TSR, BAT, OCS, OCC, and AFP. Greenhouse-based experiments included two treatments: AI and unaerated SDI (CK), during the tomato growing season in the fall of 2015. The results showed that compared with CK, AI treatment significantly increased OCC and AFP (by 16 and 7.4%, respectively), as well as TSR and OCS (by 24.21 and 22.91%, respectively) (P

We have investigated the effect of eddies (cold and warm eddies, CEs and WEs) on the nutrient supply to the euphotic zone and the organic carbon export from the euphotic zone to deeper parts of the water column in the northern South China Sea. Besides basic hydrographic and biogeochemical parameters, the flux of particulate organic carbon (POC), a critical index of the strength of the oceanic biological pump, was also measured at several locations within two CEs and one WE using floating sediment traps deployed below the euphotic zone. The POC flux associated with the CEs (85 ± 55 mg-C m−2 d−1) was significantly higher than that associated with the WE (20 ± 7 mg-C m−2 d−1). This was related to differences in the density structure of the water column between the two types of eddies. Within the core of the WE, downwelling created intense stratification which hindered the upward mixing of nutrients and favored the growth of small phytoplankton species. Near the periphery of the WE, nutrient replenishment from below did take place, but only to a limited extent. By far the strongest upwelling was associated with the CEs, bringing nutrients into the lower portion (∼50 m) of the euphotic zone and fueling the growth of larger-cell phytoplankton such as centric diatoms (e.g., Chaetoceros, Coscinodiscus) and dinoflagellates (e.g., Ceratium). A significant finding that emerged from all the results was the positive relationship between the phytoplankton carbon content in the subsurface layer (where the chlorophyll a maximum occurs) and the POC flux to the deep sea.

To better interpret summer maize stomatal conductance (gs) variation under conditions of changing water status at different growth stages, three water stress indicators, soil water content (SWC), leaf-air temperature difference (ΔT) and leaf level water stress index (CWSIL) were employed in Jarvis model, which were JS, JT and JC models respectively. Measurements of gs were conducted in a summer maize field experiment during the year 2012–2013. In the insufficient irrigation experiment, three levels of irrigation amount were applied at four different growth stages of summer maize. We constructed three scenarios to evaluate the performance of the three water stress indicators for estimating maize gs in a modified Jarvis model. Results showed that JT and JC models had better simulation accuracy than the JS model, especially at the late growth stage (Scenario 1) or considering the plant recovery compensation effects (Scenario 2). Scenario 3 indicated that the more environmental factors were adopted, the better prediction performance would be for JS model. While for JT model, two environmental factors (photosynthesis active radiation (PAR), and vapor pressure deficit (VPD)) seemed good enough to obtain a reliable simulation. When there were insufficient environmental data, CWSIL would be the best option. This study can be useful to understand the response of plant stomatal to changing water conditions and will further facilitate the application of the Jarvis model in various environments.