131 research outputs found

    The Effects of Cleaning on the Kinetics of in vitro Metal Release from Dental Casting Alloys

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    The kinetics of the release of elements from six dental casting alloys into cell-culture medium was assessed by means of atomic absorption spectroscopy. Alloys were evaluated in the polished and polished-cleaned conditions so that the effects of cleaning could be determined. Auger scanning microscopy was used for analysis of the surfaces of selected alloys before and after exposure to the cell-culture medium. Release patterns for each element were characterized by the shape of the dissolution us. time curve, concentration of the element at 12 h as a percentage of the 72-hour concentration, and the relative slope of the curve from 48 to 72 h. Three patterns of release were observed for elements in these alloys. Type I patterns had logarithmic shapes with relatively large 12-hour concentrations and low 48-72-hour slopes. Type II patterns had logarithmic shapes but with moderate 12-hour concentrations and 48-72-hour slopes. Type III patterns were polynomial in shape, had relatively low 12-hour concentrations, and had large 48-72-hour slopes. Cleaning did not change the pattern of release but did generally significantly decrease the quantities of elements released (p = 0.05). The type of dissolution vs. time curve appeared to be dependent upon the element and the composition of the alloy. When cleaning reduced dissolution, surface analyses showed that the cleaning process increased the abundance of elements such as Au and Pd and reduced the abundance of Ag and Cu. Elements which were released from the alloys were more abundant on the surface than in the bulk in both polished and polished-cleaned conditions. Auger analyses of alloy surfaces after exposure to medium showed the presence of organic films up to 50 nm thick. This study demonstrated the importance of consideration of the cleaning method and kinetic release pattern when in vitro tests which assess the cytotoxicities of these alloys are planned.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67010/2/10.1177_00220345920710071101.pd

    Alpha1-acid glycoprotein post-translational modifications: a comparative two dimensional electrophoresis based analysis

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    Alpha1-acid glycoprotein (AGP) is an immunomodulatory protein expressed by hepatocytes in response to the systemic reaction that follows tissue damage caused by inflammation, infection or trauma. A proteomic approach based on two dimensional electrophoresis, immunoblotting and staining of 2DE gels with dyes specific for post-translational modifications (PTMs) such as glycosylation and phosphorylation has been used to evaluate the differential interspecific protein expression of AGP purified from human, bovine and ovine sera. By means of these techniques, several isoforms have been identified in the investigated species: they have been found to change both with regard to the number of isoforms expressed under physiological condition and with regard to the quality of PTMs (i.e. different oligosaccharidic chains, presence/absence of phosphorilations). In particular, it is suggested that bovine serum AGP may have one of the most complex pattern of PTMs among serum proteins of mammals studied so far

    Different features of tumor-associated NK cells in patients with low-grade or high-grade peritoneal carcinomatosis

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    Peritoneal carcinomatosis (PC) is a rare disease defined as diffused implantation of neoplastic cells in the peritoneal cavity. This clinical picture occurs during the evolution of peritoneal tumors, and it is the main cause of morbidity and mortality of patients affected by these pathologies, though cytoreductive surgery with heated intra-peritoneal chemotherapy (CRS/HIPEC) is yielding promising results. In the present study, we evaluated whether the tumor microenvironment of low-grade and high-grade PC could affect the phenotypic and functional features and thus the anti-tumor potential of NK cells. We show that while in the peritoneal fluid (PF) of low-grade PC most CD56dim NK cells show a relatively immature phenotype (NKG2A+KIR\u2013CD57\u2013CD16dim), in the PF of high-grade PC NK cells are, in large majority, mature (CD56dimKIR+CD57+CD16bright). Furthermore, in low-grade PC, PF-NK cells are characterized by a sharp down-regulation of some activating receptors, primarily NKp30 and DNAM-1, while, in high-grade PC, PF-NK cells display a higher expression of the PD-1 inhibitory checkpoint. The compromised phenotype observed in low-grade PC patients corresponds to a functional impairment. On the other hand, in the high-grade PC patients PF-NK cells show much more important defects that only partially reflect the compromised phenotype detected. These data suggest that the PC microenvironment may contribute to tumor escape from immune surveillance by inducing different NK cell impaired features leading to altered anti-tumor activity. Notably, after CRS/HIPEC treatment, the altered NK cell phenotype of a patient with a low-grade disease and favorable prognosis was reverted to a normal one. Our present data offer a clue for the development of new immunotherapeutic strategies capable of restoring the NK-mediated anti-tumor responses in association with the CRS/HIPEC treatment to increase the effectiveness of the current therapy

    Metformin overdose causes platelet mitochondrial dysfunction in humans

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    Introduction. We have recently demonstrated that metformin intoxication causes mitochondrial dysfunction in several porcine tissues, including platelets. The aim of the present work was to clarify whether it also causes mitochondrial dysfunction (and secondary lactate overproduction) in human platelets, in-vitro and ex-vivo. Methods. Human platelets were incubated for 72 h with saline or increasing dose of metformin (in-vitro experiments). Lactate production, respiratory chain complex activities (spectrophotometry), mitochondrial membrane potential (flow-cytometry after staining with JC-1) and oxygen consumption (Clark-type electrode) were then measured. Platelets were also obtained from ten patients with lactic acidosis (arterial pH 6.97\ub10.18 and lactate 16\ub17 mmol/l) due to accidental metformin intoxication (serum drug level 32\ub114 mg/l) and ten healthy volunteers of similar sex and age. Respiratory chain complex activities were measured as above (ex-vivo experiments). Results. In-vitro, metformin dose-dependently increased lactate production (p<0.001), decreased respiratory chain complex I activity (p=0.009), mitochondrial membrane potential (p=0.003) and oxygen consumption (p<0.001) of human platelets. Ex-vivo, platelets taken from intoxicated patients had significantly lower complex I (p=0.045) and complex IV (p<0.001) activity compared to controls. Conclusions. Depending on dose, metformin can cause mitochondrial dysfunction and lactate overproduction in human platelets in-vitro and, possibly, in-vivo. Trial registration. NCT 0094212

    Brettanomyces bruxellensis yeasts: impact on wine and winemaking

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    Yeasts belonging to the Brettanomyces/Dekkera genus are non-conventional yeasts, which affect winemaking by causing wine spoilage all over the world. This mini-review focuses on recent results concerning the presence of Brettanomyces bruxellensis throughout the wine processing chain. Here, culture-dependent and independent methods to detect this yeast on grapes and at the very early stage of wine production are encompassed. Chemical, physical and biological tools, devised for the prevention and control of such a detrimental species during winemaking are also presented. Finally, the mini-review identifies future research areas relevant to the improvement of wine safety and sensory profiles

    THE CONCEPT OF LAW AND EFFICACY

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    Jedno od značenja izraza ‘učinkovitost’ odnosi se na činjenicu da se adresati pravnih normi stvarno ponašaju onako kako to od njih zahtijevaju pravne norme. To se značenje izraza obično koristi u filozofskopravnim raspravama glede toga je li učinkovitost bitan element pojma prava. Prema pravnom pozitivizmu, učinkovitost je u nekim slučajevima i na određene načine uvjet važenja (vrijeđenja) pravnih normi i pravnih sustava. S druge strane, pravni je realizam sklon potpunom poistovjećivanju pravnog važenja s učinkovitosti ili njegovu svođenju na učinkovitost. Prema tome, u oba je filozofskopravna pravca učinkovitost u pravilu uključena u oblikovanje njihovih pojmova prava. Međutim, dok pravnopozitivističko shvaćanje ne utječe na najuobičajenije značenje važenja pravne norme (pripadanje pravne norme pravnom sustavu), a utvrđivanjem učinkovitosti kao kriterija postojanja pravnog sustava ne dodaje mnogo objašnjenju pojma prava, pravnorealističko se shvaćanje suočava s ozbiljnim prigovorima glede svoje objašnjavalačke prikladnosti.One of the senses of the term ‘efficacy’ refers to the fact that norm-addresses actually behave as is required of them by legal norms. This sense of the term is one which is generally used within the jurisprudential discussions about whether efficacy is the essential element of the concept of law. According to legal positivism, efficacy is in some cases and in certain ways the condition of legal validity of both legal norms and legal systems. On the other hand, legal realism tends to entirely identify legal validity or reduce it to efficacy. Thus, in both jurisprudential approaches, efficacy tends to play a role in shaping their respective concepts of law. However, while the legal positivistic view does not affect the most standard sense of legal validity of the legal norm (i.e. the legal norms’ membership in the legal system), and does not add much to the explanation of the concept of law by identifying efficacy as the criterion of legal systems’ existence, the legal realistic view is faced with some serious objections regarding its explanatory adequacy

    Anales del III Congreso Internacional de Vivienda y Ciudad "Debate en torno a la nueva agenda urbana"

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    Acta de congresoEl III Congreso Internacional de Vivienda y Ciudad “Debates en torno a la NUEVa Agenda Urbana”, ha sido una apuesta de alto compromiso por acercar los debates centrales y urgentes que tensionan el pleno ejercicio del derecho a la ciudad. Para ello las instituciones organizadoras (INVIHAB –Instituto de Investigación de Vivienda y Hábitat y MGyDH-Maestría en Gestión y Desarrollo Habitacional-1), hemos convidado un espacio que se concretó con potencia en un debate transdisciplinario. Convocó a intelectuales de prestigio internacional, investigadores, académicos y gestores estatales, y en una metodología de innovación articuló las voces académicas con las de las organizaciones sociales y/o barriales en el Foro de las Organizaciones Sociales que tuvo su espacio propio para dar voz a quienes están trabajando en los desafíos para garantizar los derechos a la vivienda y los bienes urbanos en nuestras ciudades del Siglo XXI
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