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To evaluate via scanning electron microscopy the amount of smear layer generated during the use of sonic and ultrasonic activation systems with standardized short-term intentional contacts with the canal walls. Seventy single-root human teeth were randomly assigned to 2 control (n = 5 each): NC (negative control), PC (positive control) and four experimental groups (n = 15 each): NC (negative control), PC (positive control), G1 (passive ultrasonic irrigation with Irrisafe), G2 (ultrasonic irrigation with EndoUltra), G3 (sonic irrigation with Endoactivator), G4 (sonic irrigation with Eddy). Samples were instrumented with ProTaper Next®. An irrigation protocol with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) was followed for both PC and the experimental groups. Standardized intentional contacts were made in the mesial walls during 5 s at WL − 2 mm in all experimental groups. Two calibrated evaluators scored the smear layer generated with an ordinal scale by scanning electron microscopy. The weighted kappa coefficient (Kw) was calculated to determine the inter-observer agreement. Post-consensus ordinal data were analyzed using the ordinal (linear) chi-square test. When the agitation file is in contact with dentine walls, Irrisafe® significantly generated the least amount of smear layer in the coronal third (p

INTRODUCTION Laparoscopic cholecystectomy may not be suited in elderly patients with comorbidities. Our objective is to evaluate whether our indication for cholecystostomy is in accordance with the 2018 Tokio Guidelines and to determine the clinical-epidemiological and analytical characteristics as well as the clinical results depending on the treatment (surgical, conservative or cholecystostomy). MATERIAL AND METHODS Retrospective observational study with patients diagnosed with acute cholecystitis between the 25/01/2019 and the 13/03/2020. RESULTS Out of 145 patients, 87 (60%) underwent cholecystectomy (average age 63 years), 47 (32,4%) treated conservatively (74,8) and 11 (7,6%) by cholecystostomy (85,8). The multivariate analysis showed that suffering from cardio and cerebrovascular diseases, CKD, taking anticoagulants and altered levels of creatinine, Quick or CRP, multiplies by 5.2, 6.4, 10.9, 4.6, 1.2 and 1.1 the probability of cholecystostomy versus cholecystectomy (p CONCLUSIONS 1. Patients undergoing cholecystostomy are older, multipathological and present greater systemic involvement (KD, coagulopathy and elevated APR). They require a longer hospital stay and duration of antibiotic treatment. 2. 54,54% of the cholecystostomies performed were adapted to the 2018 Tokio Guidelines. 3. Conservative treatment means higher long-term complication rates.

To evaluate via scanning electron microscopy the amount of smear layer generated during the use of sonic and ultrasonic activation systems with standardized short-term intentional contacts with the canal walls.Seventy single-root human teeth were randomly assigned to 2 control (n = 5 each): NC (negative control), PC (positive control) and four experimental groups (n = 15 each): NC (negative control), PC (positive control), G1 (passive ultrasonic irrigation with Irrisafe), G2 (ultrasonic irrigation with EndoUltra), G3 (sonic irrigation with Endoactivator), G4 (sonic irrigation with Eddy). Samples were instrumented with ProTaper Next®. An irrigation protocol with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) was followed for both PC and the experimental groups. Standardized intentional contacts were made in the mesial walls during 5 s at WL - 2 mm in all experimental groups. Two calibrated evaluators scored the smear layer generated with an ordinal scale by scanning electron microscopy. The weighted kappa coefficient (KWhen the agitation file is in contact with dentine walls, Irrisafe® significantly generated the least amount of smear layer in the coronal third (p 0.05). Both in the middle and apical third, activation with Irrisafe® also showed statistically significant better results than Eddy™ and EndoUltra®. Endoactivator® showed significant better results than EndoUltra® and Eddy™ in the apical third (p 0.05).Irrisafe generated the least amount of smear layer in the entire canal and similar to Endoactivator in the apical third when the agitation file is in contact with dentine walls.The smear layer is generated during activation. It is common to apply irrigation protocols where after the removal of the smear layer using chelants, a final rinse and activation is carried out but there are no previous studies analyzing the possible creation of a new smear layer with this final activation.

The dipeptidyl peptidase IV (DPPIV) gene encodes a brush border membrane exopeptidase that is expressed in a tissue-restricted fashion. To examine the regulation of DPPIV transcription in various tissues in vivo, we examined the expression of DPPIV 5′-flanking region (promoter)–human growth hormone reporter constructs in transgenic mice. These mice exhibited cell-type specific reporter expression in kidney. Surprisingly, however, only very low to non-detectable levels of reporter were found in small intestine. These results indicate that DNA elements sufficient for DPPIV expression in kidney, but not intestine, reside in the 5′-flanking region of the gene.

"In this work a computer program for the indexing of diffractograms is presented. The diffractograms are obtained by means of a discrete Fourier transform from high resolution electron microscope images. The program requires the use of x-ray diffraction data files together with a fast Fourier transform program, for this purpose we used the Digital Micrograph software."

Mucinous colorectal cancers exhibit a characteristic set of molecular genetic alterations and may be derived from progenitor cells committed to the goblet cell lineage. Previously, we demonstrated that the MUC2 mucin gene promoter drives transgene reporter expression with high specificity in small intestinal goblet cells of transgenic mice. On the basis of these experiments, we reasoned that the MUC2 promoter could be used to drive SV40 T antigen (Tag) expression in the same cell type, decoupling them from their normal antiproliferative controls. A line of mice was established (MUCTag6) that expressed Tag in intestinal goblet cells as determined by RNA blot and immunohistochemical analysis. These goblet cells were markedly involuted however, most notably in the villi. Endogenous intestinal MUC2 message levels were reduced to about one third the normal level in these mice. However, absorptive cell lineage markers were comparable with nontransgenics. Bromodeoxyuridine-positive S-phase cells are limited to crypts in nontransgenic intestine but are present in both crypts and villi in MUCTag6. In contrast, mitotic cells were not present in the villi, indicating that MUCTag6 villi goblet cells do not progress into M phase. Apoptotic cells positive for terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling were increased more than fourfold in MUCTag6 villi (P0.0001), and apoptotic goblet cells were evident. Electron microscopic examination of MUCTag6 intestinal villi revealed the presence of degraded cell remnants containing mucin goblets together with other cell debris, further indicating apoptosis of the goblet cell lineage. Thus, the expression of Tag in intestinal goblet cells releases them from normal antiproliferative controls, causing their inappropriate entry into S phase even after they transverse the crypt/villus junction. They do not, however, progress to M phase. Instead, they undergo apoptosis with a high degree of efficiency in S or G(2) phase. These experiments demonstrate that apoptosis effectively blocks inappropriate goblet cell proliferation in the intestine, supporting its proposed role as an antineoplastic mechanism.

After the progress derived from Watson and Crick’s DNA structural model [1953], DNA has frequently been thought as a static and rigid polymer rarely disturbed by random mutations. However, the discovery of processes as transposition, hyper-mutability, genetic drive and gene conversion, shows that DNA is genetically more active than our first notion as being only the heredity keeping guard. From a physical point of view, studies of molecular dynamics and molecular structure have shown that DNA is far from being a rigid molecule. Indeed, there do exist several fluctuations in the molecule and the structure is not homogeneous along the polymer. At the evolutive level, the analysis of nucleotide sequence data has shown regularities that make evident selective constraints other than the protein function derived from amino acid sequence. Other selective constraints acting over the genome include protein synthesis kinetics, tRNA availability, mRNA secondary structure and DNA stability. Thus, genome evolution can be conceived as a dynamical and complex system which might be understood by the search of regularities in genomic nucleotide sequences.

Dielectric spectroscopy; E. coli bacteria; Maxwell–Garnet model Espectroscopia dieléctrica; Bacterias E. coli; Modelo Maxwell-Garnet; Espectroscòpia dielèctrica; Bacteris E. coli; Model Maxwell-Garnet Detection of bioparticles is of great importance in electrophoresis, identification of biomass sources, food and water safety, and other areas. It requires a proper model to describe bioparticles' electromagnetic characteristics. A numerical study of Escherichia coli bacteria during their functional activity was carried out by using two different geometrical models for the cells that considered the bacteria as layered ellipsoids and layered spheres. It was concluded that during cell duplication, the change in the dielectric permittivity of the cell is high enough to be measured at radio frequencies of the order of 50 kHz. An experimental setup based on the capacitive Wheatstone bridge was designed to measure relative changes in permittivity during cell division. In this way, the theoretical model was validated by measuring the dielectric permittivity changes in a cell culture of Escherichia coli ATTC 8739 from WDCM 00012 Vitroids. The spheroidal model was confirmed to be more accurate.