50 research outputs found

    The novel serine protease PreR-Co promotes endothelium-independent vasorelaxation in rabbit aortic rings

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    The effect of a novel enzyme (PreR-Co) that activates renal prorenin was studied on rabbit aortas with and without endothelium. It was tested 1) in the basal tone of nonstimulated or ANG II-sensitized rings or rings precontracted with norepinephrine (NE), PGF(2alpha), high KCl concentration, and 2) in rings pretreated with enalaprilat, losartan, PD-123319, N(omega)-nitro-l-arginine methyl ester, HOE-140, indomethacin, or serine protease inhibitors (PMSF, aprotinin, or soybean trypsin inhibitor); kallilkrein and bradykinin were also tested in ANG II-sensitized rings. PreR-Co produced a vasorelaxant effect in the basal tone and in the precontracted rabbit aorta. The effect was endothelium independent, potentiated by endothelium removal or nitric oxide (NO) synthase inhibition, and abolished by boiling the enzyme. In addition, the effect improved when basal tone was increased in ANG II-sensitized aortic rings or in precontracted vessels. No activation of the ANG II, bradykinin, prostaglandin, or NO pathway mediating the PreR-Co response could be obtained, suggesting a direct action of the enzyme. This action seems to be dependent on esterasic activity because serine protease inhibitors like PMSF and aprotinin were able to block the vasorelaxant effect of PreR-Co.Fil: Peral, Maria de Los Angeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Vincent, Paula Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Romano, Monica Liliana. Universidad Nacional de Tucumán. Facultad de Medicina; ArgentinaFil: Guardia, Dora Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Coviello, Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: de Vito, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentin

    Synthesis and functional evaluation of novel aldose reductase inhibitors bearing a spirobenzopyran scaffold

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    Background: Aldose reductase, the first enzyme of the polyol pathway, is the key determinant for the pathogenesis of long term diabetic complications. Accordingly, its inhibition represents the major therapeutic strategy to treat this kind of pathologies. Objectives: In this work we describe the synthesis and the functional evaluation of a number of spiro-oxazolidinone and spiro-morpholinone acetic acid derivatives, and their benzyloxy analogs, developed as aldose reductase inhibitors. Results: Most of them proved to inhibit the target enzyme, showing IC50 values in the micromolar/low micromolar range. SARs observed among the three different series allowed to highlight their key pharmacophoric elements, thus creating sound basis for the design of novel and more effective inhibitors. Conclusion: Although further substitution patterns are needed, the novel compounds here proposed represent a good starting point for the development of novel and effective ARIs

    Laser welding of tailored blanks made of Al-Si-coated 22MnB5 steel using a filler wire and a variable energy distribution laser optics

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    Laser welding of Al-Si-coated steels for hot stamping in automotive applications is problematic due to the mixing of the coating layers inside the molten pool that weakens the resulting weld seam. In this case, the most common welding procedure to overcome this issue consists in removing the Al-Si layer through laser ablation prior to the joining. This method continues to be the most widely used by major producers of tailor welded blanks, although in situ ablation of the Al-Si coating can be costly and time consuming. In this work, a novel approach consisting in joining as-received (i.e., not decoated) materials using a filler wire and an innovative variable energy distribution laser optics is introduced and tested on tailor welded blanks made of 22MnB5. Tensile tests of specimens obtained from a 3(3) full factorial design of experiment have shown an average value of ultimate tensile strength of 1523 MPa, which is much higher than the one usually observed in as-received welded then hot-stamped conditions and aligned with hot-stamped base material values. Hardness test results (494-543 HV0.5) were in the typical hot-stamped base material range of values as well, while SEM-EDS analyses detected no ferrite inclusions inside the fusion zone. Variations of the main process parameters have been considered on an iso-thickness and iso-material configuration, empirically demonstrating the stability and reliability of the proposed methodology as well as its suitability for production purposes

    Direct Anterior versus Lateral Approach for Femoral Neck Fracture: Role in COVID-19 Disease

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    Background: During the COVID-19 emergency, the incidence of fragility fractures in elderly patients remained unchanged. The management of these patients requires a multidisciplinary approach. The study aimed to assess the best surgical approach to treat COVID-19 patients with femoral neck fracture undergoing hemiarthroplasty (HA), comparing direct lateral (DL) versus direct anterior approach (DAA). Methods: A single-center, observational retrospective study including 50 patients affected by COVID-19 infection (30 males, 20 females) who underwent HA between April 2020 to April 2021 was performed. The patients were allocated into two groups according to the surgical approach used: lateral approach and anterior approach. For each patient, the data were recorded: age, sex, BMI, comorbidity, oxygen saturation (SpO2), fraction of the inspired oxygen (FiO2), type of ventilation invasive or non-invasive, HHb, P/F ratio (PaO2/FiO2), hemoglobin level the day of surgery and 1 day post operative, surgical time, Nottingham Hip Fractures Score (NHFS) and American Society of Anesthesiologists Score (ASA). The patients were observed from one hour before surgery until 48 h post-surgery of follow-up. The patients were stratified into five groups according to Alhazzani scores. A non-COVID-19 group of patients, as the control, was finally introduced. Results: A lateral position led to a better level of oxygenation (p < 0.01), compared to the supine anterior approach. We observed a better post-operative P/F ratio and a reduced need for invasive ventilation in patients lying in the lateral position. A statistically significant reduction in the surgical time emerged in patients treated with DAA (p < 0.01). Patients within the DAA group had a significantly lower blood loss compared to direct lateral approach. Conclusions: DL approach with lateral decubitus seems to preserved respiratory function in HA surgery. Thus, the lateral position may be associated with beneficial effects on gas exchange

    Acid Derivatives of Pyrazolo[1,5-a]pyrimidine as Aldose Reductase Differential Inhibitors

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    Aldose reductase (AKR1B1), the key enzyme of the polyol pathway, plays a crucial role in the development of long-term complications affecting diabetic patients. Nevertheless, the expedience of inhibiting this enzyme to treat diabetic complications has failed, due to the emergence of side effects from compounds under development. Actually AKR1B1 is a Janus-faced enzyme which, besides ruling the polyol pathway, takes part in the antioxidant defense mechanismof the body. In this workwe report the evidence that a class of compounds, characterized by a pyrazolo[1,5-a]pyrimidine core and an ionizable fragment, modulates differently the catalytic activity of the enzyme, depending on the presence of specific substrates such as sugar, toxic aldehydes, and glutathione conjugates of toxic aldehydes. The study stands out as a systematic attempt to generate aldose reductase differential inhibitors (ARDIs) intended to target long-term diabetic complications while leaving unaltered the detoxifying role of the enzyme

    Dual Kit/Aur Inhibitors as Chemosensitizing Agents for the Treatment of Melanoma: Design, Synthesis, Docking Studies and Functional Investigation

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    Melanoma is the most serious form of skin cancer but its medication is still far from being safe and thoroughly effective. The search of novel therapeutic approaches represents therefore a health emergency to push through eagerly. In this study, we describe a novel class of dual c-Kit/Aur inhibitors, characterized by a 1,2,4-triazole core and developed by a structure-based optimization of a previously developed hit, and report the evidence of their significance as drug candidates for the treatment of melanoma. Compound 6a, merging the best inhibitory profile against the target kinases, showed anti-proliferative efficacy against the human melanoma cell lines A2058, expressing the BRAF V600D mutation, and WM266-4, expressing BRAF V600E. Significantly, it displayed also a highly synergistic profile when tested in combination with vemurafenib, thus proving its efficacy not only per se but even in a combination therapy, which is nowadays acknowledged as the cornerstone approach of the forthcoming tumour management

    Quinazolinone-based rhodanine-3-acetic acids as potent aldose reductase inhibitors: Synthesis, functional evaluation and molecular modeling study

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    A series of quinazolinone-based rhodanine-3-acetic acids was synthesized and tested for in vitro aldose reductase inhibitory activity. All the target compounds displayed nanomolar activity against the target enzyme. Compounds 3a, 3b, and 3e exhibited almost 3-fold higher activity as compared to the only marketed reference drug epalrestat. Structure-activity relationship studies indicated that bulky substituents at the 3-phenyl ring of the quinazolinone moiety are generally not tolerated in the active site of the enzyme. Insertion of a methoxy group on the central benzylidene ring was found to have a variable effect on ALR-2 activity depending on the nature of peripheral quinazolinone ring substituents. Removal of the acetic acid moiety led to inactive or weakly active target compounds. Docking and molecular dynamic simulations of the most active rhodanine-3-acetic acid derivatives were also carried out, to provide the basis for further structure-guided design of novel inhibitors

    1,2-Benzisothiazole Derivatives Bearing 4-, 5-, or 6-Alkyl/arylcarboxamide Moieties Inhibit Carbonic Anhydrase Isoform IX (CAIX) and Cell Proliferation under Hypoxic Conditions

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    Three novel series of 1,2-benzisothiazole derivatives have been developed as inhibitors of carbonic anhydrase isoform IX. Compounds 5c and 5j, tested in vitro on the human colon cell line HT-29, blocked the growth of cells cultured under chemically induced hypoxic conditions, displaying a specific activity against cancer cells characterized by CAIX up-regulation. Moreover, a synergistic activity of 5c with SN-38 (the active metabolite of irinotecan) and 5-fluorouracil on cell proliferation under hypoxic conditions was demonstrated

    FOXD1-ALDH1A3 signaling is a determinant for the self-renewal and tumorigenicity of mesenchymal glioma stem cells

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    Glioma stem-like cells (GSC) with tumor-initiating activity orchestrate the cellular hierarchy in glioblastoma and engender therapeutic resistance. Recent work has divided GSC into two subtypes with a mesenchymal (MES) GSC population as the more malignant subtype. In this study, we identify the FOXD1-ALDH1A3 signaling axis as a determinant of the MES GSC phenotype. The transcription factor FOXD1 is expressed predominantly in patient-derived cultures enriched with MES, but not with the proneural GSC subtype. shRNA-mediated attenuation of FOXD1 in MES GSC ablates their clonogenicity in vitro and in vivo. Mechanistically, FOXD1 regulates the transcriptional activity of ALDH1A3, an established functional marker for MES GSC. Indeed, the functional roles of FOXD1 and ALDH1A3 are likely evolutionally conserved, insofar as RNAi-mediated attenuation of their orthologous genes in Drosophila blocks formation of brain tumors engineered in that species. In clinical specimens of high-grade glioma, the levels of expression of both FOXD1 and ALDH1A3 are inversely correlated with patient prognosis. Finally, a novel small-molecule inhibitor of ALDH we developed, termed GA11, displays potent in vivo efficacy when administered systemically in a murine GSC-derived xenograft model of glioblastoma. Collectively, our findings define a FOXD1-ALDH1A3 pathway in controling the clonogenic and tumorigenic potential of MES GSC in glioblastoma tumors

    Risk factors associated with adverse fetal outcomes in pregnancies affected by Coronavirus disease 2019 (COVID-19): a secondary analysis of the WAPM study on COVID-19.

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    Objectives To evaluate the strength of association between maternal and pregnancy characteristics and the risk of adverse perinatal outcomes in pregnancies with laboratory confirmed COVID-19. Methods Secondary analysis of a multinational, cohort study on all consecutive pregnant women with laboratory-confirmed COVID-19 from February 1, 2020 to April 30, 2020 from 73 centers from 22 different countries. A confirmed case of COVID-19 was defined as a positive result on real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay of nasal and pharyngeal swab specimens. The primary outcome was a composite adverse fetal outcome, defined as the presence of either abortion (pregnancy loss before 22 weeks of gestations), stillbirth (intrauterine fetal death after 22 weeks of gestation), neonatal death (death of a live-born infant within the first 28 days of life), and perinatal death (either stillbirth or neonatal death). Logistic regression analysis was performed to evaluate parameters independently associated with the primary outcome. Logistic regression was reported as odds ratio (OR) with 95% confidence interval (CI). Results Mean gestational age at diagnosis was 30.6+/-9.5 weeks, with 8.0% of women being diagnosed in the first, 22.2% in the second and 69.8% in the third trimester of pregnancy. There were six miscarriage (2.3%), six intrauterine device (IUD) (2.3) and 5 (2.0%) neonatal deaths, with an overall rate of perinatal death of 4.2% (11/265), thus resulting into 17 cases experiencing and 226 not experiencing composite adverse fetal outcome. Neither stillbirths nor neonatal deaths had congenital anomalies found at antenatal or postnatal evaluation. Furthermore, none of the cases experiencing IUD had signs of impending demise at arterial or venous Doppler. Neonatal deaths were all considered as prematurity-related adverse events. Of the 250 live-born neonates, one (0.4%) was found positive at RT-PCR pharyngeal swabs performed after delivery. The mother was tested positive during the third trimester of pregnancy. The newborn was asymptomatic and had negative RT-PCR test after 14 days of life. At logistic regression analysis, gestational age at diagnosis (OR: 0.85, 95% CI 0.8-0.9 per week increase; pPeer reviewe
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