Synergistic effect of octadecyl ammonium oxide and oleate amide propyl betaine and development of a foam drainage reagent for natural gas production

Betaine surfactants are used widely in oil field chemistry as well as other industrial applications, but their foaming ability is very poor so that it cannot be used in foaming. In this work, the effect of octadecyl ammonium oxide on the foam properties of oleate amide propyl betaine, a new compound foaming reagent, is studied based on foam performance. Then, a foam drainage reagent of 0.5 wt% oleate amide propyl betaine and 0.1 wt% octadecyl ammonium oxide is developed for natural gas production. Its salt resistance, methanol resistance, high temperature resistance, anti-condensate oil performance, and emulsification ability are systematically evaluated. Furthermore, the factors affecting foam performance are analyzed. The results show that the compound foaming reagent has good anti-salt, anti-methanol, and anti-condensate oil properties for meeting application requirements. The microstructures of foams derived from different reagents reveal the stability mechanism. All results reflect the fact that compounding can expand their application range in different environments to various extents, which benefits the design and use of compound surfactants

Synergistic effect of octadecyl ammonium oxide and oleate amide propyl betaine and development of a foam drainage reagent for natural gas production

Betaine surfactants are used widely in oil field chemistry as well as other industrial applications, but their foaming ability is very poor so that it cannot be used in foaming. In this work, the effect of octadecyl ammonium oxide on the foam properties of oleate amide propyl betaine, a new compound foaming reagent, is studied based on foam performance. Then, a foam drainage reagent of 0.5 wt% oleate amide propyl betaine and 0.1 wt% octadecyl ammonium oxide is developed for natural gas production. Its salt resistance, methanol resistance, high temperature resistance, anti-condensate oil performance, and emulsification ability are systematically evaluated. Furthermore, the factors affecting foam performance are analyzed. The results show that the compound foaming reagent has good anti-salt, anti-methanol, and anti-condensate oil properties for meeting application requirements. The microstructures of foams derived from different reagents reveal the stability mechanism. All results reflect the fact that compounding can expand their application range in different environments to various extents, which benefits the design and use of compound surfactants

STAT3 inhibition ameliorates renal interstitial inflammation in MRL/lpr mice with diffuse proliferative lupus nephritis

Background and objectives Acute kidney injury (AKI) is one of the most common and severe clinical syndromes of diffuse proliferative lupus nephritis (DPLN), of which poor prognosis is indicated by aggravated renal function deterioration. However, the specific therapy and mechanisms of AKI in DPLN remain to be explored.Methods The correlation between AKI and clinical pathological changes in DPLN patients was analyzed. Expression of STAT3 signaling was detected in MRL/lpr mice with DPLN using immunohistochemical staining and immunoblotting. Inhibition of STAT3 activation by combination therapy was assessed in MRL/lpr mice.Results Correlation analysis revealed only the interstitial leukocytes were significantly related to AKI in endocapillary DPLN patients. MRL/lpr mice treated with vehicle, which can recapitulate renal damages of DPLN patients, showed upregulation of STAT3, pSTAT3 and caspase-1 in renal cortex. FLLL32 combined with methylprednisolone therapy significantly inhibited the STAT3 activation, improved acute kidney damage, reduced the interstitial infiltration of inflammatory cells and decreased the AKI incidence in MRL/lpr mice.Conclusion STAT3 activation may play an important role in the pathogenesis of DPLN and the development of AKI. Hence, STAT3 inhibition based on the combination of FLLL32 with methylprednisolone may represent a new strategy for treatment of DPLN with AKI

Antibacterial activities and mechanisms of action of a defensin from manila clam Ruditapes philippinarum

Defensins represent an evolutionary ancient family of antimicrobial peptides, which played an undeniably important role in host defense. In the present study, a defensin isoform was identified and characterized from manila clam Ruditapes philippinarum (designed as Rpdef1 alpha). Multiple alignments and phylogenetic analysis suggested that Rpdef1 alpha belonged to the defensin family. Quantitative RT-PCR and immunohistochemical analysis revealed that Rpdef1 alpha transcripts and the encoding peptide were dominantly expressed in the tissues of gills and mantle. After Vibrio anguillarum challenge, the Rpdef1 alpha transcripts were significantly up-regulated in gills of clams. In addition, rRpdef1 alpha not only showed broad-spectrum antimicrobial activities towards Vibrio species, but also inhibited the formation of bacterial biofilms. Knockdown of Rpdef1 alpha transcripts caused significant increase in the cumulative mortality of manila clams post V. anguillarum challenge. Membrane integrity, scanning electron microscopy analysis and electrochemical assay indicated that rRpdef1 alpha was capable of causing bacterial membrane permeabilization and then resulted in cell death. Moreover, phagocytosis and chemotactic ability of hemocytes could be significantly enhanced after incubation with rRpdef1 alpha. Overall, these results suggested that Rpdef1 alpha could act as both antibacterial agent and opsonin to defend against the invading microorganisms in manila clam R. philippinarum

Associations between anxiety, depression, and personal mastery in community-dwelling older adults: a network-based analysis

Abstract Background In China, about 18.70% of the population aged 60 years and older are at risk of low personal mastery as well as anxiety and depression for a variety of reasons. The purpose of this study was to construct a symptom network model of the relationship between anxiety, depression, and personal mastery in community-dwelling older adults and to identify central and bridge symptoms in this network. Methods Depression, anxiety, and personal mastery were measured using the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder Scale (GAD-7), and Personal Mastery Scale (PMS), respectively. A total of 501 older adults in 16 communities in Changzhou and Zhenjiang, Jiangsu Province, China, were surveyed by using a combination of stratified sampling and convenience sampling methods. The R language was used to construct the network. Results (1) The network structure of anxiety–depression–personal mastery was stable, with “Nervousness” (node GAD1, strength = 1.38), “Sad mood” (node PHQ2, strength = 1.22), " Inability to change” (node PMS2, strength = 1.01) and “Involuntarily” (node PMS3, strength = 0.95) as the central symptoms. (2) “Irritability” (node GAD6, bridge strength = 0.743), “Sad mood” (node PHQ2, bridge strength = 0.655), and “Trouble relaxing” (node GAD4, bridge strength = 0.550) were the bridge symptoms connecting anxiety, depressive symptoms, and personal mastery. (3) In the network comparison test (NCT), residence, somatic chronic comorbidity and gender had no significant effect on network structure. Conclusions The construction of the anxiety–depression–personal mastery network structure opens up new possibilities for mechanisms of action and intervention formulation for psychological disorders in community-dwelling older adults. The identification of central symptoms (e.g., nervousness, sad mood, inability to change, involuntarily) and bridge symptoms (e.g., irritability, sad mood, trouble relaxing) in community-dwelling older adults with anxiety, depression, and low sense of mastery can provide a scientific basis for the development of precise interventions

Ag Decorated Co3O4-Nitrogen Doped Porous Carbon as the Bifunctional Cathodic Catalysts for Rechargeable Zinc-Air Batteries

The use of transition metals as bifunctional catalysts for rechargeable zinc-air batteries has recently attracted much attention. Due to their multiple chemical valence states, the cobalt oxides are considered to be promising catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this work, bifunctional Ag-decorated Co3O4-nitrogen doped porous carbon composite (Co3O4-NC&Ag) catalysts were synthesized by annealing ZIF-67 in N2 and O2, respectively, followed by Ag deposition using chemical bath deposition. Due to the decoration of Ag nanoparticles and high specific surface area (46.9 m2 g−1), the electrochemical activity of Co3O4 increased significantly. The optimized Co3O4-NC&Ag catalysts possessed superior ORR performance with a half-wave potential of 0.84 V (vs. RHE) and OER activity with an overpotential of 349 mV at 10 mA cm−2. The open circuit voltage of the Co3O4-NC&Ag-based zinc-air battery was 1.423 V. Meanwhile, the power density reached 198 mW cm−2 with a specific discharge capacity of 770 mAh g−1 at 10 mA cm−2, which was higher than that of Pt/C-based zinc-air battery (160 mW cm−2 and 705 mAh g−1). At a current density of 10 mA cm−2, the charge-discharge performance was stable for 120 h (360 cycles), exhibiting better long-term stability than the Pt/C&RuO2 counterpart

Ag Decorated Co₃O₄-Nitrogen Doped Porous Carbon as the Bifunctional Cathodic Catalysts for Rechargeable Zinc-Air Batteries

The use of transition metals as bifunctional catalysts for rechargeable zinc-air batteries has recently attracted much attention. Due to their multiple chemical valence states, the cobalt oxides are considered to be promising catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this work, bifunctional Ag-decorated Co3O4-nitrogen doped porous carbon composite (Co3O4-NC&Ag) catalysts were synthesized by annealing ZIF-67 in N2 and O2, respectively, followed by Ag deposition using chemical bath deposition. Due to the decoration of Ag nanoparticles and high specific surface area (46.9 m2 g−1), the electrochemical activity of Co3O4 increased significantly. The optimized Co3O4-NC&Ag catalysts possessed superior ORR performance with a half-wave potential of 0.84 V (vs. RHE) and OER activity with an overpotential of 349 mV at 10 mA cm−2. The open circuit voltage of the Co3O4-NC&Ag-based zinc-air battery was 1.423 V. Meanwhile, the power density reached 198 mW cm−2 with a specific discharge capacity of 770 mAh g−1 at 10 mA cm−2, which was higher than that of Pt/C-based zinc-air battery (160 mW cm−2 and 705 mAh g−1). At a current density of 10 mA cm−2, the charge-discharge performance was stable for 120 h (360 cycles), exhibiting better long-term stability than the Pt/C&RuO2 counterpart

Hypochlorite-induced oxidative stress elevates the capability of HDL in promoting breast cancer metastasis

<p>Abstract</p> <p>Background</p> <p>Previous studies suggest that oxidative stress plays an important role in the development of breast cancer. There is a significant inverse relationship between HDL and the risk and mortality of breast cancer. However, it is well known that under conditions of oxidative stress, such as breast cancer, HDL can be oxidatively modifiedand these modifications may have an effect on the functions of HDL. The purpose of this study is to determine the different effects of normal and oxidized (caused by hypochlorite-induced oxidative stress) HDL on breast cancer cell metastasis.</p> <p>Methods</p> <p>Human breast cancer cell lines were treated with normal and hypochlorite-oxidized HDL, and then cell metastasis potency <it>in vivo </it>and the abilities of migration, invasion, adhesion to HUVEC and ECM <it>in vitro </it>were examined. Integrin expression and PKC activity were evaluated, and PKC inhibitor and PKC siRNA was applied.</p> <p>Results</p> <p>We found hypochlorite-oxidized HDL dramatically promotes breast cancer cell pulmonary metastasis (133.4% increase at <it>P </it>< 0.0 l for MDA-MB-231 by mammary fat pad injection; 164.3% increase at <it>P </it>< 0.01 for MCF7 by tail vein injection) and hepatic metastasis (420% increase at <it>P </it>< 0.0 l for MDA-MB-231 by mammary fat pad injection; 1840% fold increase at <it>P </it>< 0.001 for MCF7 by tail vein injection) in nude mice, and stimulates higher cell invasion (85.1% increase at <it>P </it>< 0.00 l for MDA-MB-231; 88.8% increase at <it>P </it>< 0.00 l for MCF7;), TC-HUVEC adhesion (43.4% increase at <it>P </it>< 0.00 l for MDA-MB-231; 35.2% increase at <it>P </it>< 0.00 l for MCF7), and TC-ECM attachment (41.0% increase at <it>P </it>< 0.00 l for MDA-MB-231; 26.7% increase at <it>P </it>< 0.05 for MCF7) <it>in vitro </it>compared with normal HDL. The data also shows that the PKC pathway is involved in the abnormal actions of hypochlorite-oxidized HDL.</p> <p>Conclusions</p> <p>Our study demonstrated that HDL under hypochlorite-induced oxidative stress stimulates breast cancer cell migration, invasion, adhesion to HUVEC and ECM, thereby promoting metastasis of breast cancer. These results suggest that HDL-based treatments should be considered for treatment of breast cancer patients.</p