Effects of an efficient straw decomposition system mediated by Stropharia rugosoannulata on soil properties and microbial communities in forestland.

Cultivation of Stropharia rugosoannulata with straw in forestland is effective for straw biodegradation and can prevent the waste of straw resources and environmental pollution and generate economic benefits. However, there is a lack of systematic evaluation of spent mushroom substrate (SMS) input into forestland, such as soil properties and microbial succession. In this experiment, 0 (CK), 10 (SA), 20 (SB), 30 (SC), 40 (SD), and 50 (SE) kg/m2 straw were used to cultivate S. rugosoannulata, and two soil layers (0-10 cm, 10-20 cm) of the cultivated forestland were analyzed. The results indicated that SMS significantly promoted nutrient accumulation in forestland. The bacterial alpha diversity in the SC treatment group was greater than that in the control and gradually decreased to the control level with interannual changes, while the trend of fungal alpha diversity was opposite to that of bacterial alpha diversity. Furthermore, the SC treatment group positively affected soil nitrogen metabolism-related microorganisms for two consecutive years and significantly promoted tree growth. Habitat niche breadth and null model analysis revealed that bacterial communities were more sensitive than fungal communities after SMS input. Linear mixed model (LMM) analysis revealed that SMS supplementation significantly positively affected bacteria (Gammaproteobacteria and Bacteroidota) and significantly negatively affected fungi (Coniochaetales). The constructed fungal-bacterial co-occurrence networks exhibited modularity, and the five types of bacteria were significantly correlated with soil organic matter (SOM), soil organic carbon (SOC), available potassium (AK), available phosphorus (AAP) and available nitrogen (AN) levels. The structural equation model (SEM) showed that bacterial diversity responded more to changes in soil nutrients than did fungal diversity. Overall, 30 kg/m2 of straw decomposition and 2 years of continuous cultivation were beneficial to soil health. This study provides new insights into the rational decomposition of straw and maintenance of forestland ecological balance by S. rugosoannulata.

Clinical, biological and genome-wide comparison of carbapenem-resistant Klebsiella pneumoniae with susceptibility transformation to polymyxin B during therapy.

OBJECTIVES: The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) is a major clinical concern, and polymyxin B (PMB) is a 'last resort' antibiotic for its treatment. Understanding the effects of drug susceptibility transformation in CRKP-infected patients undergoing PMB treatment would be beneficial to optimize PMB treatment strategies. METHODS: We retrospectively collected data from patients infected with CRKP and treated with PMB from January 2018 to December 2020. CRKPs were collected before and after PMB therapy, and patients were classified into the 'transformation' group (TG) and 'non-transformation' group (NTG) by the shift of susceptibility to PMB. We compared clinical characteristics between these groups, and further analysed the phenotypic and genome variation of CRKP after PMB susceptibility transformation. RESULTS: A total of 160 patients (37 in the TG and 123 in the NTG) were included in this study. The duration of PMB treatment before PMB-resistant K. pneumoniae (PRKP) appearance in TG was even longer than the whole duration of PMB treatment in NTG (8 [8] vs. 7 [6] days; p 0.0496). Compared with isogenic PMB-susceptible K. pneumoniae (PSKP), most PRKP strains had missense mutations in mgrB (12 isolates), yciC (10 isolates) and pmrB (7 isolates). The competition index of 82.4% (28/34) of PRKP/PSKP pairs was <67.6% (23/34), and 73.5% (25/34) of PRKP strains showed a higher 7-day lethality in Galleria mellonella and a greater ability to resist complement-dependent killing than their corresponding PSKP, respectively. CONCLUSION: Low dose with longer PMB treatment durations may be associated with the emergence of polymyxin resistance. The evolution of PRKP is predominantly mediated by an accumulation of mutations, including those in mgrB, yciC, and pmrB. Lastly, PRKP exhibited reduced growth and increased virulence compared with parental PSKP.

Direct and indirect selenium speciation in biofortified wheat: A tale of two techniques.

Wheat can be biofortified with different inorganic selenium (Se) forms, selenite or selenate. The choice of Se source influences the physiological response of the plant and the Se metabolites produced. We looked at selenium uptake, distribution and metabolization in wheat exposed to selenite, selenate and a 1:1 molar mixture of both to determine the impact of each treatment on the Se speciation in roots, shoots, and grains. To achieve a comprehensive quantification of the Se species, the complementarity of high-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry and X-ray absorption spectroscopy was exploited. This approach allowed the identification of the six main selenium species: selenomethionine, selenocysteine, selenocystine, selenite, selenate, and elemental selenium. The three treatments resulted in similar total selenium concentration in grains, 90-150 mg Se kg-1 , but produced different effects in the plant. Selenite enhanced root accumulation (66% of selenium) and induced the maximum toxicity, whereas selenate favored shoot translocation (46%). With the 1:1 mixture, selenium was distributed along the plant generating lower toxicity. Although all conditions resulted in >92% of organic selenium in the grain, selenate produced mainly C-Se-C forms, such as selenomethionine, while selenite (alone or in the mixture) enhanced the production of C-Se-Se-C forms, such as selenocystine, modifying the selenoamino acid composition. These results provide a better understanding of the metabolization of selenium species which is key to minimize plant toxicity and any concomitant effect that may arise due to Se-biofortification.

Cysteine protected cells from H2O2-induced damage and promoted long-chain fatty acids synthesis in vivo to improve γ-aminobutyric acid production in Levilactobacillus brevis.

Levilactobacillus brevis NPS-QW-145 isolated from kimchi is deficient in glutamate dehydrogenase-encoding gene (gdhA) to form glutamate, hence it required exogenous supplementation of glutamate/monosodium glutamate (MSG) for decarboxylation reaction to produce γ-aminobutyric acid (GABA). However, GABA conversion rate from MSG was relatively low. The individual effect of 20 amino acids on regulating GABA biosynthesis was investigated. Cysteine was selected to significantly improve GABA production from MSG. It was found that Lb. brevis was capable of producing H2O2, cysteine protected Lb. brevis against H2O2-induced oxidative damage to increase cell viability for the enhancement of GABA production. Moreover, cysteine promoted glucose consumption to produce acetyl-CoA for synthesizing long-chain fatty acids to significantly up-regulate GABA biosynthesis. These findings deciphered antioxidative capability of cysteine in Lb. brevis 145 and provided a theoretical basis for fatty acids synthesis-mediated GABA synthesis in Lb. brevis 145, and possibly in other lactic acid bacteria.

Role of cysteine in the improvement of γ-aminobutyric acid production by nonproteolytic Levilactobacillus brevis in coculture with Streptococcus thermophilus.

Previous research has showed that nonproteolytic Levilactobacillus brevis 145 (L) in coculture with Streptococcus thermophilus 1275 (S), not Lactobacillus delbrueckii ssp. bulgaricus (Lbu), was able to produce γ-aminobutyric acid (GABA) during milk fermentation in the presence of monosodium glutamate (MSG). It was assumed that differences of casein hydrolysis patterns between Strep. thermophilus 1275 and L. bulgaricus caused the phenomenon. Moreover, the GABA content was low and residual MSG was high in SL-fermented milk. In our research, comparison of peptide profiles determined by liquid chromatography/tandem mass spectrometry showed that αS2-casein, ß-casein, and κ-casein degradation by L. bulgaricus and Strep. thermophilus varied. Importantly, the peptide number in the L and Lbu coculture group increased compared with the Lbu monoculture group, whereas the peptide number in the SL coculture group decreased in comparison with S monoculture group, suggesting that L. bulgaricus was not able to provide peptides for the growth of Lb. brevis 145. Furthermore, we found that after supplementation with cysteine (50 mg/L) during milk fermentation by SL, 10 g/L MSG was converted into 4.8 g/L GABA with a minimum level of residual MSG, viable cell counts of Lb. brevis and lactic acid production were increased, and the casein hydrolysis pattern was not influenced. Moreover, sulfhydryl group-containing chemicals including cystine, reduced glutathione, and oxidized glutathione showed effects similar to that of cysteine in improving GABA production. Finally, when L. bulgaricus YIB2 was combined with SL, supplementation of cysteine was also able to significantly improve GABA production.

Ipomoea staphylina Attenuates Potassium Dichromate-Induced Nephrotoxicity in Wistar Rats via Antioxidant and Antiapoptotic Effects.

Occupational and environmental exposure to chromium compounds leads to nephrotoxicity to humans and animals due to the overproduction of ROS. Our study was aimed to demonstrate the shielding effect of hydroethanolic extract of Ipomoea staphylina (HEIS) bark on male Wistar rats challenged with potassium dichromate (K2Cr2O7). Division of animals was done in 4 groups' viz., normal control, K2Cr2O7 control, K2Cr2O7+HEIS (100 mg/kg), and K2Cr2O7+HEIS (200 mg/kg). Except for the normal control group, other groups were challenged with a single dose (subcutaneous) of K2Cr2O7 (15 mg/kg) and then treated with HEIS (100 and 200 mg/kg) for 1 week. It was observed that animals treated with K2Cr2O7 showed a notable increase in serum creatinine, blood urea, and BUN and dwindles in protein level. These changes were significantly reversed after a 1-week treatment with HEIS (100 and 200 mg/kg). Moreover, HEIS (100 and 200 mg/kg) showed a remarkable improvement in the activity of antioxidant enzymes (GPx, CAT, and SOD) and decreased the levels of TNF-α and IL-1ß in the kidney. Furthermore, treatment with HEIS (100 and 200 mg/kg) notably decreased the activity of caspase-3 and improved the level of HO-1 especially in the K2Cr2O7+ HEIS (200 mg/kg) group. Also, the histopathological study of the kidney supported the protective effects of HEIS. Hence, HEIS bark holds a notable protective effect against K2Cr2O7-induced nephrotoxicity in rats.

Intelligent Molybdenum Disulfide Complexes as a Platform for Cooperative Imaging-Guided Tri-Mode Chemo-Photothermo-Immunotherapy.

Design of new nanoplatforms that integrates multiple imaging and therapeutic components for precision cancer nanomedicine remains to be challenging. Here, a facile strategy is reported to prepare polydopamine (PDA)-coated molybdenum disulfide (MoS2 ) nanoflakes as a nanocarrier to load dual drug cisplatin (Pt) and 1-methyl-tryptophan (1-MT) for precision tumor theranostics. Preformed MoS2 nanoflakes are coated with PDA, modified with methoxy-polyethylene glycol (PEG)-amine, and loaded with 1-MT and Pt. The formed functional 1-MT-Pt-PPDA@MoS2 (the second P stands for PEG) complexes exhibit good colloidal stability and photothermal conversion efficiency (47.9%), dual pH-, and photothermal-sensitive drug release profile, and multimodal thermal, computed tomography and photoacoustic imaging capability. Due to the respective components of Pt, MoS2 , and 1-MT that can block the immune checkpoint associated to tumoral indoleamine 2,3-dioxygenase-induced tryptophan metabolism, tri-mode chemo-photothermo-immunotherapy of tumors can be realized. In particular, under the near infrared laser irradiation, fast release of both drugs can be facilitated to achieve cooperative tumor therapy effect, and the combined immunogenic cell death induced by the dual-mode chemo-photothermo treatment and the 1-MT-induced immune checkpoint blockade can boost enhanced antitumor immune response to generate significant cytotoxic T cells for tumor killing. The developed 1-MT-Pt-PPDA@MoS2 complexes may be used as an intelligent nanoplatform for cooperative precision imaging-guided combinational tumor therapy.

Co-application of Se and a biostimulant at different wheat growth stages: Influence on grain development.

An appropriate selenium intake can be beneficial for human health. Se-biofortified food in Se-deficient regions is becoming an increasingly common practice but there are still issues to be addressed regarding the observed Se-induced toxicity to the plant. In this respect, plant biostimulants are used to enhance nutrition efficiency, abiotic stress tolerance and crop quality. In this work, the efficacy of a plant biostimulant to counteract the Se-induced stress in wheat plants is experimentally assessed. The co-application of different Se-biofortification treatments and the biostimulant at different growth stages (tillering or heading stage) was investigated. The use of micro focused X-ray spectroscopy allows us to confirm organic Se species to be the main Se species found in wheat grain and that the proportion of organic Se species is only slightly affected by the Se application stage. Our study proves that the biostimulant had a key role in the enhancement of both the amount of grains produced per spike and their dry biomass without hindering Se enrichment process, neither diminishing the Se concentration nor massively disrupting the Se species present. This information will be useful to minimize both plant toxicity and economic cost towards a more effective and plant healthy selenium supplementation.

Rapid qualitative and quantitative analyses of anthocyanin composition in berries from the Tibetan Plateau with UPLC-quadruple-Orbitrap MS and their antioxidant activities.

Nitraria tangutorum B. (NT), Hippophae rhamnoides L. (HR), Lycium ruthenicum M. (LR), Lycii fructus (LF), Rosa xanthina L. (RX), and Rubuscor chorifolius L. f. (RC) are six berries from Tibetan Plateau. They have been used in traditional folk medicine with a long history, which are rich in anthocyanins. However, detailed study of their anthocyanins remains scarce. Therefore, a method for rapid simultaneous identification and quantification of 12 anthocyanins from berries using UPLC-Quadruple-Orbitrap MS system (UPLC-Q-Orbitrap MS) was established in this work. It was verified with limit of detection (3.86-11.61 µg/L), limit of quantification (3.86-11.61 µg/L), precision (0.95-2.38%), repeatability (0.96-2.08%), stability (0.86-2.31%), mean recovery (95.8-103.1%), recovery range (93.1-107.2%) and RSD less than 5.21%. It was then used in the analysis of anthocyanins in six berries species; 8, 7, 7, 7, 6 and 9 species of anthocyanins have been identified in NT, LF, LR, HR, RC and RX, respectively based on their own retention time and exact mass in positive mode, and for the first time quantified successfully in each berry (31.11 ± 0.42-2978 ± 25.67 µg.g-1). Finally, 2, 2-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity (0.92 ± 0.12-5.61 ± 0.23 mM TE/100 g), ferric reducing antioxidant power (FRAP) (1.23 ± 0.15-7.42 ± 0.28 mM TE/100 g) and total antioxidant activity (T-AOC) assays were used to evaluate the antioxidant activities of the six berries.

A retrospective analysis of Pseudomonas aeruginosa bloodstream infections: prevalence, risk factors, and outcome in carbapenem-susceptible and -non-susceptible infections.

Background: Pseudomonas aeruginosa (PA) is a leading cause of nosocomial infections, and carbapenem non-susceptible strains are a major threat to patient safety. Methods: A single center, retrospective comparative analysis of carbapenem-non-susceptible PA (CnSPA) and carbapenem-susceptible PA (CSPA) bloodstream infections (BSIs) was conducted between January 1, 2007, and December 31, 2016. Prevalence and risk factors associated with CnSPA BSIs were examined. Results: The study enrolled 340 patients with PA BSIs; 30.0% (N = 101) of patients had CnSPA. High APACHE II scores (≥15), central venous catheterization, and delayed application of appropriate definitive therapy were independently associated with higher risk of mortality in PA BSIs. Multivariate analysis revealed that respiratory disease and exposure to carbapenems within the previous 90 days to onset of BSI were independent risk factors for acquisition of CnSPA BSIs. Overall all-cause 30-day mortality associated with PA BSIs was 26.8% (91/340). In addition, mortality was higher in patients with CnSPA than in those with CSPA (37.6% vs. 22.2%, respectively; P = 0.003). Corticosteroid therapy and delayed receipt of effective definitive therapy were independent risk factors for death from CnSPA BSIs. Conclusion: Increased incidence of CnSPA BSIs was observed during the study period, with higher mortality seen in patients with these infections. Respiratory disease and exposure to carbapenems were independent risk factors for development of CnSPA BSIs. Appropriate definitive therapy reduced mortality rates. BLBLIs were as effective as carbapenems as a treatment for PA BSIs.

[Effects of acupuncture and moxibustion on serum contents of hematopoietic growth factor in mice with marrow inhibition].

OBJECTIVE: To observe serum contents of granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) in mice with marrow inhibition before and after acupuncture and moxibustion treatment, so as to discuss the molecular biological mechanisms of acupuncture and moxibustion on improving marrow inhibition and increasing white cells after chemotherapy. METHODS: Eighty clean-grade male Kunming mice were selected and randomly divided into a normal group, a model group, an acupuncture group and a moxibustion group according to the weight, 20 cases in each one. Mice in the model group, acupuncture group and moxibustion group were injected with cyclophosphamide (CTX) to establish mice models of marrow inhibition, while mice in the normal group received intraperitoneal injection of 0.9% NaCl. Four hours after model establishment, mice in the acupuncture group and moxibustion group were treated with acupuncture or moxibustion at "Dazhui" (GV 14), "Geshu" (BL 17), "Shenshu" (BL 23) and "Zusanli" (ST 36), respectively. Mice in the normal group and model group were immobilized without any treatment. All the treatment was given once a day for consecutive 5 days. Mice blood samples were collected from caudal vein. With manual examination, the white blood cells in peripheral blood were measured on each day from model establishment to end of treatment. Enzyme linked immunosorbent assay (ELISA) method was used to measure the serum contents of GM-CSF and G-CSF 3 days and 5 days after treatment. RESULTS: Compared with the normal group, the white cells in the model group were all reduced at each time point (all P<0.05), and the serum contents of GM-CSF and G-CSF were significantly reduced (all P<0.05). Three days after treatment, compared with the model group, the white cells in the acupuncture group and moxibustion group were increased, and the difference in acupuncture group was significant (P<0.05); the serum contents of GM-CSF and G-CSF were significantly lifted (P<0.05). Four days after treatment, compared with the model group, the white cells in the acupuncture group and moxibustion group were increased (both P<0.05). Five days after treatment, compared with the model group, the white cells in the acupuncture group and moxibustion group were increased and close to the normal level; the serum contents of GM-CSF and G-CSF were significantly lifted (all P<0.05). CONCLUSION: Through increasing serum contents of GM-CSF and G-CSF in CTX mice, acupuncture and moxibustion could prompt maturation and proliferation of myeloid hematopoietic cells, which is benefit to the reconstruction of hematopoietic function and relieve the marrow inhibition caused by CTX, and thus lift peripheral white blood cells.

The endothelial protective properties of essential oil from Fructus Alpiniae zerumbet via the Akt/NOS-NO signaling pathway in vitro.

Oxidized low-density lipoprotein has been demonstrated to induce vascular injury, at least partly, through the nitric oxide-dependent pathway. Our previous studies showed that the essential oil from Fructus Alpiniae zerumbet had a capacity of antioxidation to ameliorate endothelial function and vasodilatation on aortic rings ex vivo. The present study aims to confirm the hypothesis that Fructus Alpiniae zerumbet protects against oxidized low-density lipoprotein-induced endothelial dysfunction in human aortic endothelial cells, and the role nitric oxide synthase plays in the process. Human aortic endothelial cells were pretreated with one of three different doses of Fructus Alpiniae zerumbet (1, 2, or 4 µg/mL), simvastatin (10 µM), or vehicle,followed by coincubation with oxidized low-density lipoprotein (150 µg/mL), for designed time periods. Exposure to oxidized low-density lipoprotein resulted in cytotoxicity accompanied by mitochondrial membrane potential collapse, excessive reactive oxygen species generation, and a decrease of nitric oxide production. The upregulation of inducible nitric oxide synthase mRNA and protein expression was determined by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. Furthermore, oxidized low-density lipoprotein inhibited Akt phosphorylation and downregulated endothelial nitric oxide synthase and soluble guanylatecyclase in mRNA expression and the protein level. However, cytotoxicity and aberrant reactive oxygen species and nitric oxide generation caused by oxidized low-density lipoprotein could be significantly inhibited by Fructus Alpiniae zerumbet or Sim pretreatment. Results from this study confirmed that Fructus Alpiniae zerumbet could protect against oxidized low-density lipoprotein-induced endothelial dysfunction by antioxidation and modulating the Akt/nitric oxide synthase-nitric oxide signaling pathway.

Protective effects of fractions from Pseudostellaria heterophylla against cobalt chloride-induced hypoxic injury in H9c2 cell.

ETHNOPHARMACOLOGICAL RELEVANCE: Except for as a well-known tonic Chinese herbal medicine for the treatment of splenic asthenia, anorexia, lassitude and weakness, the roots of Pseudostellaria heterophylla was also used in Chinese medicines for the treatment of palpitation. AIM OF THE STUDY: The study was designed to determine whether fractions from Pseudostellaria heterophylla could provide cardioprotection on hypoxic cardiomyocytes, what structural types of compounds were responsible for the observed effects, and which is the possible mechanism of action. MATERIALS AND METHODS: The roots of Pseudostellaria heterophylla were extracted successively with 70% aqueous ethanol and water to give a 70% ethanol extract and a water extract. The latter was first precipitated by 80% ethanol and then protein-removed by the Sevag method to give a fraction enriched in polysaccarides (PHP). The former was separated by column chromatography into a fraction enriched in small-molecule sugars and amino acids (PHSSAC), saponins (PHS), cyclopeptides (PHCP), and sapogenins (PHSG). UV spectral or chemical methods were used to confirm the five fractions. The cardioprotective effects of the fractions were evaluated by measuring the viability and the leakage of lactate dehydrogenase (LDH) of the fraction-pretreated cardiomyocyte H9c2 after exposure to CoCl2-induced hypoxia. The mechanism of action was studied by investigating the nature of cell death inhibition (by Annexin V/PI flow cytometric analysis) and their effects on the levels of malonaldehyde (MDA), superoxide dismutase (SOD) and intracellular reactive oxygen species (ROS). RESULTS: Fractions PHS and PHP could attenuate CoCl2-induced hypoxic damage to an extent higher than or comparable to the effect of the positive control N-acetyl-l-cysteine (NAC). Pretreatment of the cells with 800 µg/mL of PHS or 10mg/mL of PHP markedly decreased the level of MDA, reduced intracellular ROS, increased the activity of SOD, and reduced leakage of LDH to the levels close to or better than that with 326 µg/mL of NAC. Reduction of apoptosis was also observed for both fractions. CONCLUSIONS: The overall results suggested that the traditional use of this plant for the treatment of palpitation may be attributed to the presence of cardioprotective agents in Pseudostellaria heterophylla. PHP and PHS were the two active fractions responsible for its cardioprotective effect. The mechanism might involve protections of the cell membrane from hypoxic damage and of the cells from oxidative injury via preventing increased oxidative stress. Protection of the cells via inhibition of cellular apoptosis may also be involved.

Protective effect of oxymatrine on myocardial fibrosis induced by acute myocardial infarction in rats involved in TGF-ß1-Smads signal pathway.

Oxymatrine (1), a component extracted from a traditional Chinese herb Sophora japonica (Sophora flavescens Ait.), has been demonstrated to have a variety of pharmacological actions. Abundant experimental evidence indicates that 1 may exert a protective effect on the cardiovascular system. This study was designed to explore the possible role of 1 against myocardial fibrosis induced by acute myocardial infarction (AMI) and its modulation on transforming growth factor beta 1 (TGF-ß(1))-Smads signaling pathways. Rats with AMI induced by ligation of left anterior descending branch were randomly assigned to receive 1 50 and 25 mg/kg intragastrically, and model group which were further compared with sham-operated group, and positive group treated with captopril. The effects of 4-week therapy with 1 starting 24 h after infarction had been investigated based on (1) hemodynamics, (2) tissue weights, (3) biochemical indicator (hydroxyproline contents in left ventricle), and (4) TGF-ß(1), TGF-ß(1) receptor (TßR(1)), Smad3, Smad4, Smad7, Col1, and Col3 expression by semi-quantitative reverse transcription PCR. Treatment with 1 significantly ameliorated hemodynamics, inhibited the expression of TßR(1) mRNA and Smad3 mRNA, and reduced the left ventricle weight/body weight. The results of this research indicated that 1 might protect against myocardial fibrosis and the mechanism may be involved in modulating TGF-ß(1)-Smads signal pathway.