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Made available in DSpace on 2022-04-28T17:23:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-04-07 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) We analyzed the effectiveness of manual cleaning protocols performed on high-speed dental handpieces, using protein identification by fluorescence. Although one protocol was able to able to lower the amount of protein, >40% of the handpieces showed amounts of residual protein at unacceptable levels. Univ Fed Pernambuco, Dept Prosthodont & Oral Facial Surg, Recife, PE, Brazil Univ Sao Paulo, Med Surg Nursing Dept, Escola Enfermagem, Sao Paulo, Brazil Fed Govt, Natl Hlth Surveillance Agcy, Brasilia, DF, Brazil State Univ Sao Paulo, Sch Pharm, Dept Biol Sci, Araraquara, SP, Brazil Queen Mary Univ London, William Harvey Res Inst, London, England State Univ Sao Paulo, Sch Pharm, Dept Biol Sci, Araraquara, SP, Brazil CAPES: 001

Traveling in cognito, Henry Ford and his wife, Clara, spent April 1928 in England where guided by Herbert Morton, an engineer with Fords Manchester plant they traveled around looking for old steam ...

This paper is a personal review of the role developments in separation science over the last four decades have played in the diagnosis and understanding of purine and pyridine metabolism particularly in man. In 1967 the separation of nucleotides was used to demonstrate a new chromatography technique. This technique became known as HPLC and which continues to dominate the analysis of purines etc. The resolution and quantitation offered by even the earliest HPLC systems completely changed our understanding of matters such as nucleotide instability in cells and tissues, diagnosis of in born errors, etc. Capillary Electrophoresis also enabled high resolution as well as the quantitation of usual analytes such allantoin. Now LC-MS dominates the diagnostic field. This paper is based on the Anne Simmonds Lecture given by the author at PP17 in Gdansk in 2017.

Paracetamol is arguably the most commonly used analgesic and antipyretic drug worldwide, however its mechanism of action is still not fully established. It has been shown to exert effects through multiple pathways, some actions suggested to be mediated via N-arachidonoylphenolamine (AM404). AM404, formed through conjugation of paracetamol-derived p-aminophenol with arachidonic acid in the brain, is an activator of the capsaicin receptor, TRPV1, and inhibits the reuptake of the endocannabinoid, anandamide, into postsynaptic neurons, as well as inhibiting synthesis of PGE2 by COX-2. However, the presence of AM404 in the central nervous system following administration of paracetamol has not yet been demonstrated in humans. Cerebrospinal fluid (CSF) and blood were collected from 26 adult male patients between 10 and 211 minutes following intravenous administration of 1 g of paracetamol. Paracetamol was measured by high-performance liquid chromatography with UV detection. AM404 was measured by liquid chromatography-tandem mass spectrometry. AM404 was detected in 17 of the 26 evaluable CSF samples at 5–40 nmol⋅L−1. Paracetamol was measurable in CSF within 10 minutes, with a maximum measured concentration of 60 μmol⋅L−1 at 206 minutes. This study is the first to report on the presence of AM404 in human CSF following paracetamol administration. This may represent an important finding in our understanding of paracetamol’s mechanism of action, although measured concentrations were far below the previously documented IC50 for this metabolite., Video abstract

Ciclosporin is used as an immunosuppressant in post-organ transplantation. Recently, many questions have been raised about using generic substitutes, especially with narrow therapeutic index drugs (NTIDs). In this study, a simple high-performance liquid chromatography (HPLC) method was developed, validated and applied to detection ciclosporin in dissolution testing. Seven ciclosporin products (gelatin capsules) were included in this study, obtained from Columbia (C), Egypt (E), India (I), Jordan (J), Pakistan (P), Saudi Arabia (S), and Turkey (T). The dissolution test was done for all capsules. The Conditions were as follows: 500 ml deionized water as the medium in apparatus 2 (Pharmatest, Germany), temperature 37.5 ± 0.5°C; 50 rev/min, sampling times were 5, 10, 15, 30, 60 and 90 min with 5 ml for each sample. HPLC separation was done by a C18 column, 5 μm, (4.6 × 250 mm, ACE 5) held at 50 ± 0.3°C. Analytes were isocratically eluted at 0.7 ml/min with acetonitrile and water (70+30%) and 0.03% trifluoroacetic acid, over the 25-min run time. The intra-day and inter-day imprecision for ciclosporin across the standard range was

The Sailing Stone project animates a stone sculpture such that a traditional, large scale, normally static installation physically interacts with the public. The Sailing Stone moves so as to disrupt the normal motion of visitors to the space so as to encourage changes in the nature of the interaction between visitors and the sculpture itself. The public gallery space is monitored through a network of video cameras, and this information is used to develop a model of human motion through the gallery space. Based on this model of visitor motion, a motion plan is developed and executed for the sculpture so as to maximally disrupt the motion paths of visitors.

Background HIF-1 deficiency has marked effects on tumour glycolysis and growth. We therefore investigated the consequences of HIF-1 deficiency in mice, using the well established Hepa-1 wild-type (WT) and HIF-1β-deficient (c4) model. These mechanisms could be clinically relevant, since HIF-1 is now a therapeutic target. Methods Hepa-1 WT and c4 tumours grown in vivo were analysed by 18FDG-PET and 19FDG Magnetic Resonance Spectroscopy for glucose uptake; by HPLC for adenine nucleotides; by immunohistochemistry for GLUTs; by immunoblotting and by DIGE followed by tandem mass spectrometry for protein expression; and by classical enzymatic methods for enzyme activity. Results HIF-1β deficient Hepa-1 c4 tumours grew significantly more slowly than WT tumours, and (as expected) showed significantly lower expression of many glycolytic enzymes. However, HIF-1β deficiency caused no significant change in the rate of glucose uptake in c4 tumours compared to WT when assessed in vivo by measuring fluoro-deoxyglucose (FDG) uptake. Immunohistochemistry demonstrated less GLUT-1 in c4 tumours, whereas GLUT-2 (liver type) was similar to WT. Factors that might upregulate glucose uptake independently of HIF-1 (phospho-Akt, c-Myc) were shown to have either lower or similar expression in c4 compared to WT tumours. However the AMP/ATP ratio was 4.5 fold higher (p < 0.01) in c4 tumours, and phosphofructokinase-1 (PFK-1) activity, measured at prevailing cellular ATP and AMP concentrations, was up to two-fold higher in homogenates of the deficient c4 cells and tumours compared to WT (p < 0.001), suggesting that allosteric PFK activation could explain their normal level of glycolysis. Phospho AMP-Kinase was also higher in the c4 tumours. Conclusions Despite their defective HIF-1 and consequent down-regulation of glycolytic enzyme expression, Hepa-1 c4 tumours maintain glucose uptake and glycolysis because the resulting low [ATP] high [AMP] allosterically activate PFK-1. This mechanism of resistance would keep glycolysis functioning and also result in activation of AMP-Kinase and growth inhibition; it may have major implications for the therapeutic activity of HIF inhibitors in vivo. Interestingly, this control mechanism does not involve transcriptional control or proteomics, but rather the classical activation and inhibition mechanisms of glycolytic enzymes.

Insulin is the most specific beta cell antigen and a potential primary autoantigen in type 1 diabetes. Insulin autoantibodies (IAAs) are the earliest marker of beta cell autoimmunity; however, only slightly more than 50% of children and even fewer adults newly diagnosed with type 1 diabetes are IAA positive. The aim of this investigation was to determine if oxidative post-translational modification (oxPTM) of insulin by reactive oxidants associated with islet inflammation generates neoepitopes that stimulate an immune response in individuals with type 1 diabetes. oxPTM of insulin was generated using ribose and various reactive oxygen species. Modifications were analysed by SDS-PAGE, three-dimensional fluorescence and MS. Autoreactivity to oxPTM insulin (oxPTM-INS) was observed by ELISA and western blotting, using sera from participants with type 1 or type 2 diabetes and healthy controls as probes. IAA was measured using the gold-standard radiobinding assay (RBA). MS of oxPTM-INS identified chlorination of Tyr16 and Tyr26; oxidation of His5, Cys7 and Phe24; and glycation of Lys29 and Phe1 in chain B. Significantly higher binding to oxPTM-INS vs native insulin was observed in participants with type 1 diabetes, with 84% sensitivity compared with 61% sensitivity for RBA. oxPTM-INS autoantibodies and IAA co-existed in 50% of those with type 1 diabetes. Importantly 34% of those with diabetes who were IAA negative were oxPTM-INS positive. Altogether, 95% of participants with type 1 diabetes presented with autoimmunity to insulin by RBA, oxPTM-INS or both. Binding to oxPTM-INS was directed towards oxPTM-INS fragments with slower mobility than native insulin. These data suggest that oxPTM-INS is a potential autoantigen in individuals with new-onset type 1 diabetes.

Advanced oxidation protein products (AOPP) are reportedly elevated in the plasma of patients with a number of diseases, including diabetes mellitus, that involve oxidative stress. However, the accurate measurement of AOPP in human plasma is hampered by the formation of a precipitate following the addition of potassium iodide and glacial acetic acid according to the published assay procedure. Here we describe a modification of the AOPP assay which eliminates interference by precipitation and provides a robust, reliable, and reproducible protocol for the measurement of iodide oxidising capacity in plasma samples (intra-assay CV 1.7–5.3%, interassay CV 5.3–10.5%). The improved method revealed a significant association of AOPP levels with age (p<0.05) and hypertension (p=0.01) in EDTA-anticoagulated plasma samples from 52 patients with diabetes and 38 nondiabetic control subjects, suggesting a possible link between plasma oxidising capacity and endothelial and/or vascular dysfunction. There was no significant difference between AOPP concentrations in diabetic (74.8 ± 7.2 μM chloramine T equivalents) and nondiabetic (75.5 ± 7.0 μM chloramine T equivalents) individuals.

On a very wet evening in November 2014 Barnsley Metropolitan Council held a spectacular light show to mark the Official opening of the Elsecar Atmospheric engine after a period restoration to worki...

Previous studies on face preferences have found that online and laboratory experiments yield similar results with samples from developed countries, where the majority of the population has internet access. No study has yet explored whether the same holds true in developing countries, where the majority of the population does not have internet access. This gap in the literature has become increasingly important given that several online studies are now using cross-country comparisons. We therefore sought to determine if an online sample is representative of the population in the developing country of El Salvador. In studies of Hispanic men and women aged 18-25, we tested facial masculinity and adiposity preferences by collecting data in person as well as online. Our results showed that there were no differences in preferences between people who reported having internet access, whether they were tested online or in person. This provides evidence that testing style does not bias preferences among the same population. On the other hand, our results showed multiple differences in preferences between people who reported having internet access and people who reported not having internet access. More specifically, we found that people without internet access preferred more feminine men, more masculine women, and women with higher adiposity than people with internet access. We also found that people without internet access had fewer resources (e.g. running water) than people with internet access, suggesting that harshness in the environment may be influencing face preferences. These findings suggest that online studies may provide a distorted perspective of the populations in developing countries.