Methyl eucomate

The crystal structure of the title compound [systematic name: methyl 3-carboxy-3-hydr­oxy-3-(4-hydroxy­benz­yl)propanoate], C12H14O6, is stabilized by inter­molecular O—H⋯O and C—H⋯O hydrogen bonds. The mol­ecules are arranged in layers, parallel to (001), which are inter­connected by the O—H⋯O hydrogen bonds

Research on unsteady performance of a two-stage self-priming centrifugal pump

In order to study the unsteady performance of a two-stage self-priming centrifugal pump, the unsteady numerical calculation in a two-stage self-priming centrifugal pump was performed and energy characteristics experiments and self-priming experiments were carried out. The pressure pulsation and radial force in the pump were then analyzed. The results show that numerical calculation values are close to the experiment values. Head deviation of the pump is less than 3 %, and efficiency deviation of the pump is less than 2 percentage points. Compared with monitoring point P1, the pressure fluctuation coefficient of monitoring point P3 at the design flow rate is reduced by 61 %. Compared with monitoring point P8, the pressure fluctuation coefficient of monitoring point P5 is reduced by 70 %. The radial force on the radial guide-vane is obviously smaller than that on the volute. Under the same flow rate, radial force on the volute of second-stage pump is almost 20 times larger than that on the radial guide-van of first-stage pump

Combinatorial Effect of Non-Steroidal Anti-inflammatory Drugs and NF-κB Inhibitors in Ovarian Cancer Therapy

Several epidemiological studies have correlated the use of non-steroidal anti-inflammatory drugs (NSAID) with reduced risk of ovarian cancer, the most lethal gynecological cancer, diagnosed usually in late stages of the disease. We have previously established that the pro-apoptotic cytokine melanoma differentiation associated gene-7/Interleukin-24 (mda-7/IL-24) is a crucial mediator of NSAID-induced apoptosis in prostate, breast, renal and stomach cancer cells. In this report we evaluated various structurally different NSAIDs for their efficacies to induce apoptosis and mda-7/IL-24 expression in ovarian cancer cells. While several NSAIDs induced apoptosis, Sulindac Sulfide and Diclofenac most potently induced apoptosis and reduced tumor growth. A combination of these agents results in a synergistic effect. Furthermore, mda-7/IL-24 induction by NSAIDs is essential for programmed cell death, since inhibition of mda-7/IL-24 by small interfering RNA abrogates apoptosis. mda-7/IL-24 activation leads to upregulation of growth arrest and DNA damage inducible (GADD) 45 α and γ and JNK activation. The NF-κB family of transcription factors has been implicated in ovarian cancer development. We previously established NF-κB/IκB signaling as an essential step for cell survival in cancer cells and hypothesized that targeting NF-κB could potentiate NSAID-mediated apoptosis induction in ovarian cancer cells. Indeed, combining NSAID treatment with NF-κB inhibitors led to enhanced apoptosis induction. Our results indicate that inhibition of NF-κB in combination with activation of mda-7/IL-24 expression may lead to a new combinatorial therapy for ovarian cancer

Experimental Study on the Effect of Gas Volume Fraction on the Cavitation Performance of a Low-Specific-Speed Centrifugal Pump

In order to study the cavitation performance of centrifugal pumps with low specific speeds under the condition of gas–liquid two-phase flow, a cavitation test rig for pumping gas–liquid two-phase flow was set up. The cavitation performance of the pump with a specific speed of 32 was studied. The variation of the head, pressure pulsation intensity, and vibration intensity with the cavitation allowance NPSHa (Net Positive Suction Head available) of the centrifugal pump were obtained at different inlet gas volume fraction (IGVF) conditions of 0, 1%, 2%, and 3%. The results show that the cavitation performance of a low-specific-speed centrifugal pump can be improved obviously in a certain liquid flow range when the IGVF is 1%, especially at a low liquid flow rate. When cavitation did not occur or the degree of cavitation was low, a lower IGVF can reduce pressure pulsation intensity at the pump outlet and the vibration intensity at the pump inlet under design flow rate and high flow rate conditions. Additionally, all performances of the low-specific-speed pump are more sensitive to gas when the liquid flow rate is low. The results can provide a reference for improving the cavitation performance of low-specific-speed pumps for transporting gas–liquid two-phase flow and single-phase liquids

Novel lactotransferrin-derived synthetic peptides suppress cariogenic bacteria in vitro and arrest dental caries in vivo: [Novel lactotransferrin-derived anticaries peptides]

Objectives: The aim of the study was to design and synthesise novel lactotransferrin-derived antimicrobial peptides (AMPs) with enhanced antibacterial activity against cariogenic bacteria. Methods: We obtained the LF-1 (WKLLRKAWKLLRKA) and LF-2 (GKLIWKLLRKAWKLLRKA) AMPs, based on the N-terminal functional sequence of lactotransferrin, and characterised their physicochemical properties and secondary structure. Their antibacterial activity against caries-associated bacteria was evaluated using bacterial susceptibility and time-killing assays, as well as transmission electron microscopy (TEM). The antibiofilm activity against Streptococcus mutans biofilms was determined using biofilm susceptibility assays and confocal laser scanning microscopy (CLSM). A rodent model of dental caries was adopted to evaluate their anticaries effectiveness in vivo. Results: Both peptides possessed an α-helical structure with excellent amphipathicity. LF-1 was effective against S. mutans and Actinomyces species, whereas LF-2 showed more potent antibacterial activity than LF-1 against a broader spectrum of tested strains. Both peptides inhibited the formation of S. mutans biofilm starting at 8 μmol/L and exerted effective eradication of S. mutans in preformed biofilms. Both peptides exhibited satisfactory biocompatibility and exerted significant anticaries effects in a rodent model. Conclusions: Both lactotransferrin-derived peptides displayed strong antimicrobial activity against cariogenic bacteria and S. mutans biofilm in vitro and effectively inhibited dental caries in vivo

Experimental Study on the Effect of Gas Volume Fraction on the Cavitation Performance of a Low-Specific-Speed Centrifugal Pump

In order to study the cavitation performance of centrifugal pumps with low specific speeds under the condition of gas–liquid two-phase flow, a cavitation test rig for pumping gas–liquid two-phase flow was set up. The cavitation performance of the pump with a specific speed of 32 was studied. The variation of the head, pressure pulsation intensity, and vibration intensity with the cavitation allowance NPSHa (Net Positive Suction Head available) of the centrifugal pump were obtained at different inlet gas volume fraction (IGVF) conditions of 0, 1%, 2%, and 3%. The results show that the cavitation performance of a low-specific-speed centrifugal pump can be improved obviously in a certain liquid flow range when the IGVF is 1%, especially at a low liquid flow rate. When cavitation did not occur or the degree of cavitation was low, a lower IGVF can reduce pressure pulsation intensity at the pump outlet and the vibration intensity at the pump inlet under design flow rate and high flow rate conditions. Additionally, all performances of the low-specific-speed pump are more sensitive to gas when the liquid flow rate is low. The results can provide a reference for improving the cavitation performance of low-specific-speed pumps for transporting gas–liquid two-phase flow and single-phase liquids

Serum Cystatin C within 24 hours after admission: a potential predictor for acute kidney injury in Chinese patients with community acquired pneumonia

AbstractBackground Acute kidney injury (AKI) is common in patients with community-acquired pneumonia (CAP), and is associated with poor prognosis. Therefore, in this study, we evaluated whether AKI in Chinese patients with CAP could be well predicted by serum Cystatin C within 24 h after admission.Methods Univariate and multivariate logistic regression analyses were used to investigate independent factors of AKI in patients with CAP.Results Totally, 2716 patients with CAP were included in this study. 766 (28%) patients developed AKI. After multivariate logistic regression analysis, serum Cystatin C (odds ratio [OR] 4.27, 95% confidence interval [CI] 3.36–5.44; p < 0.001) was an independent factor for AKI in patients with CAP. Serum Cystatin C had an area under the receiver operating characteristic curve (AUC) of 0.81 for predicting AKI, with an optimal cutoff value of 1.37 mg/L, computing 68% sensitivity, 80% specificity. Furthermore, serum Cystatin C within 24 h after admission still had a good and stable prediction efficiency for AKI in various subgroups (age, gender, hypertension, diabetes, coronary artery disease, cardiac insufficiency, cerebrovascular disease, atrial fibrillation, chronic obstructive pulmonary disease, chronic kidney disease, and tumor, albumin, anemia, platelet count, white blood cell count, and uric acid, confusion, uremia, respiratory rate, blood pressure, and age 65 years or older [CURB-65] score, acute respiratory failure, intensive care unit admission, and mechanical ventilation) of patients with CAP (AUCs: 0.69–0.84).Conclusion Serum Cystatin C within 24 h after admission appears to be a good biomarker for predicting AKI in Chinese patients with CAP

Antimicrobial peptide GH12 suppresses cariogenic virulence factors of Streptococcus mutans

Cariogenic virulence factors of Streptococcus mutans include acidogenicity, aciduricity, and extracellular polysaccharides (EPS) synthesis. The de novo designed antimicrobial peptide GH12 has shown bactericidal effects on S. mutans, but its interaction with virulence and regulatory systems of S. mutans remains to be elucidated. The objectives were to investigate the effects of GH12 on virulence factors of S. mutans, and further explore the function mechanisms at enzymatic and transcriptional levels. To avoid decrease in bacterial viability, we limited GH12 to subinhibitory levels. We evaluated effects of GH12 on acidogenicity of S. mutans by pH drop, lactic acid measurement and lactate dehydrogenase (LDH) assay, on aciduricity through survival rate at pH 5.0 and F1F0-ATPase assay, and on EPS synthesis using quantitative measurement, morphology observation, vertical distribution analyses and biomass calculation. Afterwards, we conducted quantitative real-time PCR to acquire the expression profile of related genes. GH12 at 1/2 MIC (4 mg/L) inhibited acid production, survival rate, EPS synthesis, and biofilm formation. The enzymatic activity of LDH and F1F0-ATPase was inhibited, and ldh, gtfBCD, vicR, liaR, and comDE genes were significantly downregulated. In conclusion, GH12 inhibited virulence factors of S. mutans, through reducing the activity of related enzymes, downregulating virulence genes, and inactivating specific regulatory systems

Antimicrobial peptide GH12 targets Streptococcus mutans to arrest caries development in rats

Background:Targeting Streptococcus mutans, the principle cariogenic bacterium, could prove to be an effective means of preventing dental caries. A de novo designed antimicrobial peptide, GH12, has shown bactericidal effects on S. mutans and inhibitory effects on virulence and regulatory systems of S. mutans. However, the effects of GH12 on caries remain to be elucidated.Objectives: The objectives of this study were to evaluate the direct effects of GH12 on caries and numbers of S. mutansin vivo.Design: The Keyes score was evaluated in a rodent model and in vivo S. mutans was quantified by qPCR. To further interpret the in vivo anticaries efficacy, an in vitro biofilm model using short-term treatments with GH12 mimicked treatments in vivo was adopted. Results: In vivo data showed that GH12 at 8 mg/L reduced the incidence and severity of caries. Furthermore, GH12-treated animals had less S. mutans infection. In vitro data revealed that GH12 reduced the number of S. mutans within the biofilm, as well as reducing lactic acid and water-insoluble EPS synthesis of S. mutans biofilms. Afterwards, all rats showed no significant difference in weight gain, and no sign of harm to the mucosa, indicating that GH12 possessed good biocompatibility in vivo.Conclusion: Due to the combined inhibitory effects of GH12 on the biomass and cariogenic properties of S. mutans biofilms, the population of S. mutans in vivo was reduced, residual S. mutans biofilms were less acidic and compact, and thereby the onset and development of caries were arrested. Such findings collectively certified the clinical prospects for GH12