435 research outputs found

    Synthesis of Pyrazoles by 1,3-Dipolar Cycloaddition under Aqueous Micellar Catalysis

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    Ethyl diazoacetate (EDA), which is easily prepared from ethyl glycinate and NaNO2, reacts in situ with alkynes in a water micelle environment without organic solvent to form pyrazoles. The reaction is pH dependent, as in the presence of protic catalysis (H2SO4 4%, pH 3.5) a mixture of 3,5- and 4,5-disubstituted pyrazoles was obtained, while, at pH 5.5, only the 3,5-disubstituted isomer was obtained. The presence of the surfactant TPGS-750-M was crucial to secure clean crude reaction mixtures and high yields of the products. The same protocol was successfully applied to the synthesis of substituted pyrazolines. © 2022 The Author

    Three new Alpha1-Antitrypsin deficiency variants help to define a C-Terminal region regulating conformational change and polymerization

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    Alpha1-antitrypsin (AAT) deficiency is a hereditary disorder associated with reduced AAT plasma levels, predisposing adults to pulmonary emphysema. The most common genetic AAT variants found in patients are the mildly deficient S and the severely deficient Z alleles, but several other pathogenic rare alleles have been reported. While the plasma AAT deficiency is a common trait of the disease, only a few AAT variants, including the prototypic Z AAT and some rare variants, form cytotoxic polymers in the endoplasmic reticulum of hepatocytes and predispose to liver disease. Here we report the identification of three new rare AAT variants associated to reduced plasma levels and characterize their molecular behaviour in cellular models. The variants, called Mpisa (Lys259Ile), Etaurisano (Lys368Glu) and Yorzinuovi (Pro391His), showed reduced secretion compared to control M AAT, and accumulated to different extents in the cells as ordered polymeric structures resembling those formed by the Z variant. Structural analysis of the mutations showed that they may facilitate polymerization both by loosening ‘latch’ interactions constraining the AAT reactive loop and through effects on core packing. In conclusion, the new AAT deficiency variants, besides increasing the risk of lung disease, may predispose to liver disease, particularly if associated with the common Z variant. The new mutations cluster structurally, thus defining a region of the AAT molecule critical for regulating its conformational state

    <b><i>Topoisomerase 1</i></b> Promoter Variants and Benefit from Irinotecan in Metastatic Colorectal Cancer Patients

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    Objective: Topoisomerase 1 (topo-1) is an important target for the treatment of metastatic colorectal cancer (CRC). The aim of the present study was to evaluate the correlation between topo-1 single-nucleotide polymorphisms (SNPs) and clinical outcome in metastatic CRC (mCRC) patients. Methods: With the use of specific software (PROMO 3.0), we performed an in silico analysis of topo-1 promoter SNPs; the rs6072249 and rs34282819 SNPs were included in the study. DNA was extracted from 105 mCRC patients treated with FOLFIRI ± bevacizumab in the first line. SNP genotyping was performed by real-time PCR. Genotypes were correlated with clinical parameters (objective response rate, progression-free survival, and overall survival). Results: No single genotype was significantly associated with clinical variables. The G allelic variant of rs6072249 topo-1 SNP is responsible for GC factor and X-box-binding protein transcription factor binding. The same allelic variant showed a nonsignificant trend toward a shorter progression-free survival (GG, 7.5 months; other genotypes, 9.3 months; HR 1.823, 95% CI 0.8904-3.734; p = 0.1). Conclusion: Further analyses are needed to confirm that the topo-1 SNP rs6072249 and transcription factor interaction could be a part of tools to predict clinical outcome in mCRC patients treated with irinotecan-based regimens

    Optimizing food ordering in a multi-stage catering supply chain network using reusable containers

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    Reusable plastic containers (RPCs) prevent packaging waste in the food supply chains. Food Catering Supply Chain (FCSC) made of multi-stage logistic networks represents a challenging scenario for adopting RPCs to optimize, particularly when the container's flow meets the food supplies. This paper fosters the application of RPCs in such FCSC by proposing a food-ordering MILP model to aid the cross-docking player in selecting the suppliers and releasing packaged food orders efficiently. This model optimizes logistic costs and operations as well as the influence of the container pooler's facilities network in the FCSC. A numerical example extracted by a larger case study provides validation of the model and offers insights for future research investigations

    an application of collaborative robots in a food production facility

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    Abstract Despite the food industry being a leading sector of the European economy, the level of penetration of automation is still low. The main reasons lie on the small margin of food items which does not encourage technological investments, the extremely spread vendors market i.e. mostly small and medium enterprises, and the high level of flexibility and care required to handle food products along production, packaging, and storage operations. Nevertheless, the advent of collaborative, small and flexible robots provides great opportunities for the design and development of new effective processes integrating the human flexibility with the efficiency of automation. This paper explores the impact of adopting collaborative robots in the food catering industry, by illustrating a case study developed for the end-of-line of a catering production system. A generalizable methodology is proposed to support the study of the technical and economic feasibility of the implementation of such technology. This methodology is intended to support managers of the food industry to analyse the constraints that limit the automation of a process and to measure the expected performance of the system in terms of throughput, ergonomics and economic benefits resulting from the adoption of collaborative robots

    The molecular species responsible for α₁‐antitrypsin deficiency are suppressed by a small molecule chaperone

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    The formation of ordered Z (Glu342Lys) α1‐antitrypsin polymers in hepatocytes is central to liver disease in α1‐antitrypsin deficiency. In vitro experiments have identified an intermediate conformational state (M*) that precedes polymer formation but this has yet to be identified in vivo. Moreover, the mechanism of polymer formation and their fate in cells have been incompletely characterised. We have used cell models of disease in conjunction with conformation‐selective monoclonal antibodies and a small molecule inhibitor of polymerization to define the dynamics of polymer formation, accumulation and secretion. Pulse‐chase experiments demonstrate that Z α1‐antitrypsin accumulates as short chain polymers that partition with soluble cellular components and are partially secreted by cells. These precede the formation of larger, insoluble polymers with a longer half‐life (10.9 +/‐ 1.7 h and 20.9 +/ 7.4 h for soluble and insoluble polymers respectively). The M* intermediate (or a byproduct thereof) was identified in the cells by a conformation‐specific monoclonal antibody. This was completely abrogated by treatment with the small molecule which also blocked the formation of intracellular polymers. These data allow us to conclude that: the M* conformation is central to polymerization of Z α1‐antitrypsin in vivo; preventing its accumulation represents a tractable approach for pharmacological treatment of this condition; polymers are partially secreted; and polymers exist as two distinct populations in cells whose different dynamics have likely consequences for the aetiology of the disease

    New method to detect histone acetylation levels by flow cytometry

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    Background: Reversible histone acetylation affects chromatin structural organization, thus regulating gene expression and other nuclear events. Levels of histone acetylation are tightly modulated in normal cells, and alterations of their regulating mechanisms have been shown to be involved in tumorigenesis. Methods: We developed a new flow cytometric technique for detection of histone acetylation, based on a specific monoclonal antibody that recognizes acetylated histone tails. Bivariate analysis for histone acetylation levels and DNA were performed to study modulation of chromatin organization during the cell cycle and after induction of histone hyperacetylation by the histone deacetylase (HDAC) inhibitor trichostatin A (TSA). Histone acetylation and transcription levels were monitored during differentiation induced by retinoic acid alone or in combination with TSA. Blood samples from patients were analyzed with the described protocol to monitor the effects of HDAC inhibitors in vivo and validate the developed protocol for clinical usage. Results: Flow cytometric detection of acetylation status can successfully detect modifications induced by HDAC inhibitor treatment in vivo as demonstrated by analysis of various blood samples from patients treated with valproic acid. Changes in acetylation levels during the cell cycle demonstrated a reproducible increase in histone acetylation during the replication phase that was subsequently decreased at the G2M entrance, thus paralleling the behavior of DNA replication and transcriptional activity. Conclusions: Multiparameter analysis of histone acetylation and expression of molecular markers, DNA ploidy, and/or cell cycle kinetics can provide a quick and statistically reliable tool for the diagnosis and evaluation of treatment efficacy in clinical trials using HDAC inhibitors

    Primary tumor sidedness and benefit from FOLFOXIRI plus bevacizumab as initial therapy for metastatic colorectal cancer. Retrospective analysis of the TRIBE trial by GONO

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    Right-sided metastatic colorectal cancer (mCRC) patients have poor prognosis and achieve limited benefit from first-line doublets plus a targeted agent. In this unplanned analysis of the TRIBE study, we investigated the prognostic and predictive impact of primary tumor sidedness in mCRC patients and the differential impact of the intensification of the chemotherapy in subgroups defined according to both primary tumor sidedness and RAS and BRAF mutational status
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