Functional effects of CYP1A2, NAT1, and NAT2 genetic variants in nucleotide excision repair-deficient human fibroblasts : implications for toxicological risk from environmental arylamines.

Arylamine N-acetyltransferase 1 (NAT1) and 2 (NAT2) catalyze the detoxification and/or activation of aromatic and heterocyclic amine carcinogens by two pathways. This metabolism reaction can lead to the detoxification by Nacetylation, or bioactivation by a-acetylation often preceded by CYP450 hydroxylation. Human NAT2 polymorphisms are characterized by rapid, intermediate, and slow acetylator phenotypes, thus resulting in differences in the rate of arylamine metabolism and consequently cancer risk. We have constructed nucleotide excision repair-deficient human cell model expressing human CYP1A2 and human NAT1and NAT2 in order to investigate carcinogen metabolism and cancer susceptibility in human cells. In this study we introduce the utilization of SV40-transformed human fibroblasts (GM4429) to examine the functional effects of human NAT2 haplotypes, in the presence of human NAT1. Many carcinogens, such as 4- aminobiphenyl, are metabolized by both NAT1 and NAT2, consequently both isozymes have toxicologically significant functions in the metabolism of arylamines. Furthermore, both NAT1 and NAT2 isozymes are expressed in human liver, where they are significant to carcinogen detoxification and/or activation consequences. With this model, we can examine the role of NAT1 and NAT2 carcinogen metabolism and genotoxicity in a NER-deficient human cell. In this study, we investigate novel inhibitors of NAT1 and NAT2. Previous studies have identified approximately 150 NAT inhibitor candidates following computer-based in silico screening of approximately 20 million compounds. The inhibitory properties of these compounds were tested using a High Performance Liquid Chromatography assay specific for human NAT1 and NAT2. A novel compound was identified that is an effective inhibitor of NAT1 (100%) and NAT2 (90%). This inhibitor was selective for NAT1 (IC50 about 1 µM), compared to an IC50 of 82.2µM (SMZ) for NAT2. Further studies will determine potency and efficacy of NAT inhibitors to reduce DNA adduct formation and mutagenesis. We have also successfully constructed and characterized NER-deficient human fibroblast cells with stable expression of human NAT2 alleles (NAT2*4, NAT2*S8, or NAT 2*78) and CYP1 A2. These models are used to better understand the effects of NAT2 haplotypes on carcinogen metabolism and DNA adduct formation in human cells

Role of human arylamine N-acetyltransferase in carcinogen metabolism and human breast cancer progression.

Human arylamine N-acetyltransferase (NAT) is a phase II cytosolic enzyme that occurs as two isozymes, NAT1 and NAT2. This family of polymorphic enzymes catalyzes the detoxification and/or activation of many aromatic and heterocyclic amine drugs and carcinogens. These metabolism reactions can lead to detoxification of xenobiotics by N-acetylation, or bioactivation by O-acetylation which is preceded by cytochrome P450 (CYP) hydroxylation. This study evaluates the role of human arylamine N-acetyltransferase in carcinogen metabolism as it pertains to substrate selectivity, kinetic activity towards arylamine and alkylaniline substrates, and toxicological risk. Here we introduce the use of immortalized human fibroblasts (GM4429) to investigate the effects of combinations of human NAT1, human NAT2 haplotypes (NA T2*4, NA T2*S8, or NAT2*78), and varying CYP1 A2 enzymatic activity on carcinogen metabolism. We determined the apparent Michaelis-Menten constants of human NAT1 and human NAT2 for several well-characterized and putative environmental carcinogens. We utilized these data to investigate NAT substrate selectivity for these compounds of interest. NAT1 has been implicated in several cancers including urinary bladder, colorectal, lung, and breast cancer. Studies suggest that NAT1 plays an important role in cell growth and survival, as well as in cell proliferation and cell invasion, which are hallmarks of metastatic cancer. Here we describe the use of computational screening to identify effective, novel small molecule inhibitors of the molecular target NAT1. Our lead compound, Compound 10, suppressed carcinogen metabolism and 4-aminobiphenyl (ASP) -induced DNA adducts. The results in this study show that upon NAT1 inhibition there is a significant decrease in ASP activation, cell invasion, and cell proliferation in human breast adenocarcinoma cells. We also show that NAT1 inhibition in human breast cancer cells resulted in mitotic arrest, which supports findings suggesting that NAT1 plays an important role in human breast cancer progression. Our results indicate that human NAT1 is a molecular target for cancer therapy

Precision Rock Excavation: Beyond Controlled Blasting and Line Drilling

The strictness of the result of an excavation, whether mechanical or by means of explosives, is naturally conditioned by the objective, and therefore by the type of technique applied to achieve it. To attain the best results in terms of rock breakage and respect of the final profile, it’s im-portant to evaluate the excavation specific energy and its optimization. This research being a re-vision of different techniques to achieve good quality of the final walls, it focuses on evaluating the effects of those techniques on the quality of the result, both in open-pit and underground op-erations. Different geometries and configurations can be applied to both quarrying and tunnel-ling blasts. The research is aimed to push contour blasts to their limits, and the main aspects are discussed in order to improve the blast parameters in the daily practice

Generation of strong magnetic fields by r-modes in millisecond accreting neutron stars: induced deformations and gravitational wave emission

Differential rotation induced by the r-mode instability can generate very strong toroidal fields in the core of accreting, millisecond spinning neutron stars. We introduce explicitly the magnetic damping term in the evolution equations of the r-modes and solve them numerically in the Newtonian limit, to follow the development and growth of the internal magnetic field. We show that the strength of the latter can reach large values, $B \sim 10^{14}$ G, in the core of the fastest accreting neutron stars. This is strong enough to induce a significant quadrupole moment of the neutron star mass distribution, corresponding to an ellipticity |\epsilon_B}| \sim 10^{-8}. If the symmetry axis of the induced magnetic field is not aligned with the spin axis, the neutron star radiates gravitational waves. We suggest that this mechanism may explain the upper limit of the spin frequencies observed in accreting neutron stars in Low Mass X-Ray Binaries. We discuss the relevance of our results for the search of gravitational waves.Comment: 11 pages, 8 figure

CNL2ASP: converting controlled natural language sentences into ASP

Answer Set Programming (ASP) is a popular declarative programming language for solving hard combinatorial problems. Although ASP has gained widespread acceptance in academic and industrial contexts, there are certain user groups who may find it more advantageous to employ a higher-level language that closely resembles natural language when specifying ASP programs. In this paper, we propose a novel tool, called CNL2ASP, for translating English sentences expressed in a controlled natural language (CNL) form into ASP. In particular, we first provide a definition of the type of sentences allowed by our CNL and their translation as ASP rules, and then exemplify the usage of the CNL for the specification of both synthetic and real-world combinatorial problems. Finally, we report the results of an experimental analysis conducted on the real-world problems to compare the performance of automatically generated encodings with the ones written by ASP practitioners, showing that our tool can obtain satisfactory performance on these benchmarks. Under consideration in Theory and Practice of Logic Programming (TPLP).Comment: Under consideration in Theory and Practice of Logic Programming (TPLP

Fish Skin Graft: Narrative Review and First Application for Abdominal Wall Dehiscence in Children

Summary: Acellular fish skin grafts (FSGs) are tissue-based products created by minimally processing the skin of the Atlantic cod (Gadus morhua). The FSG is rich in omega-3 and facilitates tissue regeneration by supporting revascularization and ingrowth in the proliferation and remodeling phases of wound healing. FSG is structurally more similar to human skin than antiviral-processed skin substitutes such as amniotic membrane, and there are no known prion, bacterial, or viral diseases that can be transmitted from North-Atlantic cod to humans. The FSG is processed using a proprietary method that preserves the structure and lipid composition of the skin. FSG is CE marked, and US Food and Drug Administration cleared for multiple clinical applications in partial and full-thickness wounds. FSG is currently the only acellular dermal matrix product that does not originate from mammalian tissues. For this narrative review, Medline and UpToDate were used to include a total of 21 articles published from 2015 to 2022 about fish skin graft use. We also reported a case of a 7-year-old boy who underwent treatment with FSG for abdominal wall dehiscence at our department of pediatric surgery, IRCCS Sant’Orsola- Malpighi, Alma Mater Studiorum, University of Bologna, University Hospital of Bologna. FSG provides a valuable and sustainable treatment that improves wound healing in both adult and pediatric populations. We described the first application of an FSG for wound dehiscence of the abdominal wall in a pediatric patient, reporting how FSG was completely reabsorbed and improved the skin’s repai

Correction: Human Cardiac Progenitor Spheroids Exhibit Enhanced Engraftment Potential

[This corrects the article DOI: 10.1371/journal.pone.0137999.]

Human Cardiac Progenitor Spheroids Exhibit Enhanced Engraftment Potential

A major obstacle to an effective myocardium stem cell therapy has always been the delivery and survival of implanted stem cells in the heart. Better engraftment can be achieved if cells are administered as cell aggregates, which maintain their extra-cellular matrix (ECM). We have generated spheroid aggregates in less than 24 h by seeding human cardiac progenitor cells (hCPCs) onto methylcellulose hydrogel-coated microwells. Cells within spheroids maintained the expression of stemness/mesenchymal and ECM markers, growth factors and their cognate receptors, cardiac commitment factors, and metalloproteases, as detected by immunofluorescence, q-RT-PCR and immunoarray, and expressed a higher, but regulated, telomerase activity. Compared to cells in monolayers, 3D spheroids secreted also bFGF and showed MMP2 activity. When spheroids were seeded on culture plates, the cells quickly migrated, displaying an increased wound healing ability with or without pharmacological modulation, and reached confluence at a higher rate than cells from conventional monolayers. When spheroids were injected in the heart wall of healthy mice, some cells migrated from the spheroids, engrafted, and remained detectable for at least 1 week after transplantation, while, when the same amount of cells was injected as suspension, no cells were detectable three days after injection. Cells from spheroids displayed the same engraftment capability when they were injected in cardiotoxin-injured myocardium. Our study shows that spherical in vivo ready-to-implant scaffold-less aggregates of hCPCs able to engraft also in the hostile environment of an injured myocardium can be produced with an economic, easy and fast protocol

Convento di San Francesco a Folloni: the function of a Medieval Franciscan Friary seen through the burials

Background: The Franciscan Friary in Montella near Avellino in Southern Italy is of special interest because according to historical sources it was founded by St. Francis himself in AD 1221-1222. Human remains of several hundred individuals interred in the cloister walk have been unearthed during two excavation campaigns conducted in 2007-2008 and 2010. The environs of the friary have remained rural since the foundation preventing much modern contamination. The state of preservation of the skeletons is fair to good making a suite of analyses worthwhile. Results: The skeletons have been examined anthropologically and tissue samples have been subjected to radiocarbon dating, stable isotope measurements and trace element analyses by Inductively Coupled Plasma Mass Spectrometry and Cold Vapour Atomic Absorption Spectrometry. Conclusions: The radiocarbon dates are consistent with the historical sources and show that the cemetery in the cloister walk has been in uninterrupted use from the foundation of the friary in AD 1221-1222 and until the cemetery went out of use in AD 1524. The anthropological investigations show that the individuals interred at the friary would have been shorter than other Italians from the same time, and it seems that tuberculosis was more prevalent than leprosy. Isotopic measurements show a mixed agricultural and pastoral diet and none of the individuals were consuming marine protein. Based on the trace element analysis it seems that the people resided mainly at two distinct geographical areas, one of which was Montella. One individual stands out from the rest, because he was born and raised at some third geographical location distinct from Montella and because he sports the second oldest radiocarbon date of AD 1050-1249 (two sigma calibrated range). This date is consistent with the first generation of the founders of the friary-perhaps one of St. Francis' fellow travellers from Assisi