Diverse animal models for Chlamydia infections: unraveling pathogenesis through the genital and gastrointestinal tracts.

Chlamydia trachomatis is responsible for infections in various mucosal tissues, including the eyes, urogenital, respiratory, and gastrointestinal tracts. Chronic infections can result in severe consequences such as blindness, ectopic pregnancy, and infertility. The underlying mechanisms leading to these diseases involve sustained inflammatory responses, yet thorough comprehension of the underlying mechanisms remains elusive. Chlamydial biologists employ in multiple methods, integrating biochemistry, cell biology, and genetic tools to identify bacterial factors crucial for host cell interactions. While numerous animal models exist to study chlamydial pathogenesis and assess vaccine efficacy, selecting appropriate models for biologically and clinically relevant insights remains a challenge. Genital infection models in animals have been pivotal in unraveling host-microbe dynamics, identifying potential chlamydial virulence factors influencing genital pathogenicity. However, the transferability of this knowledge to human pathogenic mechanisms remains uncertain. Many putative virulence factors lack assessment in optimal animal tissue microenvironments, despite the diverse chlamydial infection models available. Given the propensity of genital Chlamydia to spread to the gastrointestinal tract, investigations into the pathogenicity and immunological impact of gut Chlamydia become imperative. Notably, the gut emerges as a promising site for both chlamydial infection vaccination and pathogenesis. This review elucidates the pathogenesis of Chlamydia infections and delineates unique features of prevalent animal model systems. The primary focus of this review is to consolidate and summarize current animal models utilized in Chlamydia researches, presenting findings, discussions on their contributions, and suggesting potential directions for further studies.

Governing cross-border healthcare in mainland China: a scoping review of national policies from 2002 to 2022.

This study reviews national-level policies regulating cross-border healthcare in mainland China after it acceded to the World Trade Organization (WTO). Policy documents from official websites of the State Council and 19 ministries were screened, from which 487 policy documents were analyzed. WTO's five modes of trade and WHO's six building blocks of healthcare system were used to guide the analysis of policymaking patterns, charting of policy evolution process, identification of key policy areas, differentiation of 29 detailed policy themes, and identification of major countries/regions involved in cross-border healthcare. The findings lead to four policy recommendations: (1) to establish a national-level committee to govern cross-border healthcare, (2) to build an information system to comprehensively integrate various information on cross-border healthcare consumption and provision, (3) to take more proactive policy actions in healthcare internationalization, and (4) to carry out reform experiments in key sub-national regions to fully explore various possibilities in developing and regulating cross-border healthcare.

Immature persimmon residue as a novel biosorbent for efficient removal of Pb(II) and Cr(VI) from wastewater: Performance and mechanisms.

Owing to the powerful affinity of tannin toward heavy metal ions, it is frequently immobilized on adsorbents to enhance their adsorption properties. However, natural adsorbents containing tannin have been overlooked owing to its water solubility. Herein, a novel natural adsorbent based on the immature persimmon residue (IPR) with soluble tannin removed was fabricated to eliminate Pb(II) and Cr(VI) in aquatic environments. The insoluble tannin in IPR endowed it with prosperous properties for eliminating Pb(II) and Cr(VI), and the IPR achieved maximum Pb(II) and Cr(VI) adsorption quantities of 68.79 mg/g and 139.40 mg/g, respectively. Kinetics and isothermal adsorption analysis demonstrated that the removal behavior was controlled by monolayer chemical adsorption. Moreover, the IPR exhibited satisfactory Pb(II) and Cr(VI) removal efficiencies even in the presence of multiple coexisting ions and showed promising regeneration potential after undergoing five consecutive cycles. Additionally, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) analysis unveiled that the elimination mechanisms were primarily electrostatic attraction, chelation and reduction. Overall, the IPR, as a tannin-containing biosorbent, was verified to possess substantial potential for heavy metal removal, which can provide new insights into the development of novel natural adsorbents from the perspective of waste resource utilization.

Hypoglycemic activity of immature persimmon (Diospyros kaki Thunb.) extracts and its inhibition mechanism for α-amylase and α-glucosidase.

Persimmon tannins, particularly in immature persimmons, haven't yet received corresponding attention to research on therapy of diabetes mellitus in spite of high hypoglycemic activity. To accurately screening key hypoglycemic components, immature persimmon extracts were isolated and identified using enzyme affinity ultrafiltration and HRLC-ESI-MS/MS. Among them, Hederagenin (IC50 = 0.077 ± 0.003 mg/mL), Ursolic acid (IC50 = 0.001 ± 0.000 mg/mL) and Quercetin dehydrate (IC50 = 0.081 ± 0.001 mg/mL) exhibited the strongest inhibitory effect on α-amylase (HSA and PPA) and α-glucosidase, respectively. And their inhibition mechanisms were analyzed using multi-spectral analysis, atomic force microscope and molecular docking, indicating the bonding with starch digestion enzymes through hydrogen bonding and hydrophobic interaction, and generating the enzyme aggregation. In vivo starch-tolerance experiment further verified that these inhibitors could improve postprandial hyperglycemia (17.18 % âˆ¼ 40.29 %), far more than acarbose. Suppressing, Hederagenin and Ursolic acid as triterpenoids appeared amazing potentiality to alleviate postprandial hyperglycemia, which suggested that IPE were comprehensive exploration values on prevention and treatment of hyperglycemia.

Investigation of Poly(MM-EM-BM) as Nanosealing Materials in Oil-Based Drilling Fluids: Synthesis and Evaluation.

Nanosealing technology has become the key to overcoming the wellbore instability problem in deep and ultradeep shale formations. In this Article, the terpolymer poly(MM-EM-BM) was synthesized from methyl methacrylate, ethyl methacrylate, and butyl methacrylate by a Michael addition reaction. The poly(MM-EM-BM) nanoparticles were investigated by Fourier transform infrared spectroscopy, laser scattering analysis, and thermogravimetric analysis. The results imply that the particle size range of poly(MM-EM-BM) is between 33.90 and 135.62 nm and the average diameter is about 85.95 nm at room temperature, which can maintain excellent stability at 382.75 °C. The effects of poly(MM-EM-BM) on the properties of oil-based drilling fluids (OBDFs) were ascertained through experiments on the rheological performance, electrical stability, and high-temperature and high-pressure (HTHP) filtration loss. The results suggested that when the amount of added poly(MM-EM-BM) increases, the apparent viscosity, plastic viscosity, dynamic shear force, and demulsification voltage of the drilling fluids will increase correspondingly; in contrast, the HTHP filtration loss gradually decreased. When poly(MM-EM-BM) is added at 0.75%, the kinetic-to-plastic ratio of the drilling fluids is 0.24 and the filtration loss is 0.6 mL, showing excellent overall performance. The drilling fluids have a good rock-carrying ability and water loss wall-building property. The sealing performance and mechanism of poly(MM-EM-BM) were researched by the method of a sealing performance test under high temperature. The results indicated that the more poly(MM-EM-BM) used, the higher the sealing efficiency of the mud cake and the core as the sealing medium. When poly(MM-EM-BM) was added at 0.75%, the sealing rates of the mud cake and the core as the sealing medium reached the maximum sealing rates of 40.30% and 91.48%, respectively. When poly(MM-EM-BM) enters the core nanopore joint for a certain distance under formation pressure, a tight sealing layer will be formed to effectively prevent the entry of filtrate. Poly(MM-EM-BM) as a potential oil-based nanosealing agent is expected to solve the problem caused by wellbore instability in shale horizontal wells.

Partial substitution of manure reduces nitrous oxide emission with maintained yield in a winter wheat crop.

Conventional fertilization of agricultural soils results in increased N2O emissions. As an alternative, the partial substitution of organic fertilizer may help to regulate N2O emissions. However, studies assessing the effects of partial substitution of organic fertilizer on both N2O emissions and yield stability are currently limited. We conducted a field experiment from 2017 to 2021 with six fertilizer regimes to examine the effects of partial substitution of manure on N2O emissions and yield stability. The tested fertilizer regimes, were CK (no fertilizer), CF (chemical fertilizer alone, N 300 kg ha-1, P2O5 150 kg ha-1, K2O 90 kg ha-1), CF + M (chemical fertilizer + organic manure), CFR (chemical fertilizer reduction, N 225 kg ha-1, P2O5 135 kg ha-1, K2O 75 kg ha-1), CFR + M (chemical fertilizer reduction + organic manure), and organic manure alone (M). Our results indicate that soil N2O emissions are primarily regulated by soil mineral N content in arid and semi-arid regions. Compared with CF, N2O emissions in the CF + M, CFR, CFR + M, and M treatments decreased by 16.8%, 23.9%, 42.0%, and 39.4%, respectively. The highest winter wheat yields were observed in CF, followed by CF + M, CFR, and CFR + M. However, the CFR + M treatment exhibited lower N2O emissions while maintaining high yield, compared with CF. Four consecutive years of yield data from 2017 to 2021 illustrated that a single application of organic fertilizer resulted in poor yield stability and that partial substitution of organic fertilizer resulted in the greatest yield stability. Overall, partial substitution of manure reduced N2O emissions while maintaining yield stability compared with the synthetic fertilizer treatment during the wheat growing season. Therefore, partial substitution of manure can be recommended as an optimal N fertilization regime for alleviating N2O emissions and contributing to food security in arid and semi-arid regions.

Synthesis of the Oil-Based Nanoblocker Poly(MMA-BMA-BA-St) and the Study of the Blocking Mechanism.

Well wall instability is one of the problems that seriously affect the efficiency of oil and gas drilling and extraction, and the economic losses caused by accidents due to well wall instability amount to billions of dollars every year. Aiming at the fact that well wall stabilization is the current technical difficulty of drilling shale gas horizontal wells with oil-based drilling fluids, the oil-based nanoplugging agent poly(MMA-BMA-BA-St) was synthesized by the Michael addition reaction with compounds such as styrene, methyl methacrylate, and butyl methacrylate as raw materials. The structure and characteristics of the oil-based nanoblocker poly(MMA-BMA-BA-St) were characterized by infrared spectroscopy, particle size analysis, and thermal weight loss analysis. The particle size distribution of poly(MMA-BMA-BA-St) is 80.56-206.61 nm, with an average particle size of 137.10 nm, and it can resist the high temperature of 372 °C. The effects of poly(MMA-BMA-BA-St) on the performance parameters of oil-based drilling fluids were investigated by rheological experiments, electrical stability tests, and HTHP filtration loss experiments. The results show that when poly(MMA-BMA-BA-St) is added at 0.5 wt %, it has less influence on the rheological parameters of drilling fluids, the breaking emulsion pressure remains basically unchanged, the stability of the drilling fluid is better, the dynamic-plastic ratio of the drilling fluid is higher than 0.27, the filtration loss is the lowest, and it shows good rock-carrying properties. The results of mud cake experiments and artificial lithology experiments show that poly(MMA-BMA-BA-St) has the best sealing effect, with a mud cake permeability of 1.12 × 10-4 mD and a sealing rate of 30.00% when added at 0.5 wt %; the artificial core permeability was 4.0 × 10-4 mD, and the sealing rate was 91.23%. Poly(MMA-BMA-BA-St) showed good sealing performance. The oil-based nanoplugging agent poly(MMA-BMA-BA-St) has good dispersion in oil-based drilling fluids and can enter the nanopore joints to form a dense plugging layer under the action of formation pressure to prevent the intrusion of drilling fluids, thus reducing the impact of drilling fluids on the formation, maintaining the stability of the well wall and reducing downhole complications.

Evaluation of carbon mineralization and its temperature sensitivity in different soil aggregates and moisture regimes: A 21-year tillage experiment.

Characterizing soil organic carbon (SOC) mineralization and its temperature sensitivity (Q10) under different soil moisture in tillage systems is crucial for determining global carbon balance under climate warming and increasing precipitation. Aggregate protection can potentially govern SOC mineralization and its Q10. However, how tillage and aggregate sizes affect SOC mineralization and its Q10, especially under varying soil moisture, remains unclear. Soil samples (0-10 cm and 10-20 cm) were collected from a 21-year field study with four tillage treatments: conventional tillage (CT), reduced tillage (RT), no-tillage (NT), and subsoiling (SS). Bulk soil and dry-sieved aggregates were incubated at 15°C and 25°C at low, medium, and high moistures (i.e., 40%, 70%, and 100% water-holding capacity, respectively). Macro-aggregates (> 0.25 mm) had lower SOC mineralization relative to micro-aggregates (< 0.25 mm) across all soil temperatures, moistures, and depths (P < 0.01), which was attributed to their lower SOC quality (i.e., higher ratio of SOC to total nitrogen and lower ratio of dissolved organic carbon to SOC). Moreover, NT and SS promoted macro-aggregation relative to CT and RT, and thereby decreased mineralization (P < 0.001). However, Q10 was higher in macro-aggregates than in micro-aggregates at low and medium moistures. The Q10 was negatively correlated with the SOC quality in macro-aggregates (P < 0.05). The macroaggregate-associated SOC quality was lower under NT and SS than under CT and RT, which resulted in a greater Q10 under NT and SS at low and medium moistures, suggesting that NT and SS may accelerate SOC losses under global warming. Furthermore, increased soil moisture could lower Q10, and no differences among tillage practices were observed at high moisture levels (P > 0.05). Overall, our findings indicated that NT and SS decreased SOC mineralization but increased Q10 because of their large amounts of macro-aggregates with low SOC quality, and the improvement of Q10 was constrained by increasing soil moisture.

Past terrestrial hydroclimate sensitivity controlled by Earth system feedbacks.

Despite tectonic conditions and atmospheric CO2 levels (pCO2) similar to those of present-day, geological reconstructions from the mid-Pliocene (3.3-3.0 Ma) document high lake levels in the Sahel and mesic conditions in subtropical Eurasia, suggesting drastic reorganizations of subtropical terrestrial hydroclimate during this interval. Here, using a compilation of proxy data and multi-model paleoclimate simulations, we show that the mid-Pliocene hydroclimate state is not driven by direct CO2 radiative forcing but by a loss of northern high-latitude ice sheets and continental greening. These ice sheet and vegetation changes are long-term Earth system feedbacks to elevated pCO2. Further, the moist conditions in the Sahel and subtropical Eurasia during the mid-Pliocene are a product of enhanced tropospheric humidity and a stationary wave response to the surface warming pattern, which varies strongly with land cover changes. These findings highlight the potential for amplified terrestrial hydroclimate responses over long timescales to a sustained CO2 forcing.

Phosphorus deficiency induces root proliferation and Cd absorption but inhibits Cd tolerance and Cd translocation in roots of Populus × euramericana.

To disclose how phosphorus deficiency influence phytoremediation of Cd contamination using poplars, root architecture, Cd absorption, Cd translocation and antioxidant defense in poplar roots were investigated using a clone of Populus × euramericana. Root growth was unaltered by Cd exposure regardless of P conditions, while the degree of root proliferation upon P deficiency was changed by high level of Cd exposure. The concentration and content of Cd accumulation in roots were increased by P deficiency. This can be partially explained by the increased expression of genes encoding PM H + -ATPase under the combined conditions of P deficiency and high Cd exposure, which enhanced Cd2+-H+ exchanges and led to an increment of Cd uptake under P deficiency. Despite of the increasing Cd accumulation in roots, the translocation of Cd from roots to aerial tissues sharply decreased upon P deficiency. The relative expression of genes responsible for Cd translocation (HMA4) decreased upon P deficiency and thus inhibited Cd translocation via xylem. GR activity was decreased by P deficiency, which can inhibit the form of GSH and GSH-Cd complexes and decrease Cd translocation via GSH-Cd complexes. The transportation of PC-Cd complexes into vacuole decreased under P deficiency as a result of the low expression of PCS and ABCC1, and thus suppressed Cd tolerance and Cd detoxification in roots. Moreover, P deficiency decreased the levels of antioxidase (GR and CAT) and phytohormones including JA, ABA and GA3, which synchronously reduced antioxidant capacity in roots.

Phosphorus influence Cd phytoextraction in Populus stems via modulating xylem development, cell wall Cd storage and antioxidant defense.

The soils in mining lands with cadmium (Cd) contamination usually are deficient in nutrients. Disclosing how P nutrition and N:P stoichiometric ratio influences Cd accumulation and stress tolerance in stems of Populus spp. will facilitate the phytoremediation of mining sites polluted by Cd. In this study, investigations at the anatomical and physiological levels were conducted using a clone of Populus × euramericana. Both phosphorus deficiency and cadmium exposure inhibited xylem development via reducing cell layers in the xylem. Under P-sufficient condition, appropriate P status and balanced N:P ratio in stem promoted xylem development under Cd exposure via stimulating cell division, which enhanced Cd accumulation in stems. Cd accumulation in cell walls of collenchyma tissues of the stem was enhanced by P application due to increased polysaccharide production and cell wall affinity for Cd. The low P concentrations (0.3-0.4 mg g-1) and imbalanced N:P ratio under P deficiency inhibited the production of APX and ascorbate-GSH cycle, which increased oxidative stress and lipid peroxidation as indicated by high MDA concentration in stem. Under P-sufficient condition, the interactions between phytohormones and antioxidants play crucial roles in the process of antioxidant defense under Cd exposure. In conclusions, appropriate P addition and balanced N:P ratio enhanced secondary xylem development and promoted cadmium accumulation and stress tolerance in Populus stems, which can benefit the phytoextraction of Cd from Cd-contaminated soil.

Lycopene protects against atrazine-induced hepatotoxicity through modifications of cytochrome P450 enzyme system in microsomes.

Atrazine (ATR) is primarily distributed in liver and hazardous to animal health. Cytochrome P450 enzyme system (CYP450s) is responsible for the biotransformation of toxic substances. Lycopene (LYC) prevents the herbicide-induced toxicity. However, it is unclear that LYC protects against ATR-induced hepatotoxicity via modifying CYP450s. To ascertain the chemoprevention of LYC on ATR-induced hepatotoxicity, male Kunming mice were treated with LYC (5mg/kg) and/or ATR (50mg/kg or 200mg/kg) by gavage administration for 21 days. These results showed that ATR induced the increase of total CYP450 and Cytochrome b5 (Cyt b5) contents and stimulated the activities of CYP450s enzymes (erythromycin N-demethylase (ERND), aminopyrin N-demethylase (APND), aniline-4-hydeoxylase (AH) and NADPH-cytochrome c reductase (NCR)) in hepatic microsomes. The mRNA expressions of six CYP450s genes (increase: CYP1a1, CYP2a4, CYP3a57 and decrease: CYP2f2, CYP3a11, CYP4a31) were significantly influenced by ATR. LYC modulated the contents and activities of CYP450s and normalized the expressions of four CYP450s genes (CYP1b1, CYP2a4, CYP2e1, and 4A14). These findings suggested that ATR induced hepatic CYP450s disturbance and influenced the gene expression of CYP450s. Lycopene protected against hepatic CYP450s disturbance induced by ATR via modifying the hepatic CYP450s activities and transcription in mice.