37 research outputs found

    Adhesive systems modified with antimicrobial agents: a literature review

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    A cárie secundária é a principal causa de falha da restauração. Assim, o desenvolvimento de adesivos com ação antimicrobiana é uma opção vantajosa para sua inibição. No entanto, esse efeito deve ser comprovado, bem como que o benefício adicional não interfere nas propriedades mecânicas do material ou na biocompatibilidade. Analisamos adesivos com ação antimicrobiana por meio de testes microbiológicos, resistência de união, grau de conversão e citotoxicidade. Analisamos 32 estudos com adesivos antimicrobianos disponíveis comercialmente (Clearfil ™ SE Protect Bond / MDPB, Gluma 2Bond / glutaraldeído, Peak Universal Bond / clorexidina) e materiais experimentais ou adesivos comerciais modificados com agentes antimicrobianos, incluindo materiais com metacrilato de amônio quaternário (QAM) [metacrilato de dimetilaminododecil (DMADDM) e metacrilato de dimetilaminohexadecil (DMAHDM)], nanopartículas [prata (NAg), dióxido de titânio (TiO2), óxido de zinco (ZnO)], vidro bioativo dopado com prata ou zinco (BAG), titânio, iodo de titânio, cobre e compostos como triclosan, quercetina, extrato de semente de uva, entre outros. O uso de agentes antimicrobianos é uma perspectiva favorável para a funcionalização de sistemas adesivos para inibir a cárie secundária. No entanto, mais estudos clínicos precisam provar a eficácia desses materiais.Secondary caries is the primary cause of restoration failure. Thus, the development of adhesives with antimicrobial action is an advantageous option for their inhibition. However, this effect must be proven, as well as that the additional benefit does not interfere with material mechanical properties or biocompatibility. We analyzed adhesives with antimicrobial action by microbiological tests, bond strength, degree of conversion, and cytotoxicity. We analyzed 32 studies with commercially available antimicrobial adhesives (Clearfil™ SE Protect Bond/ MDPB, Gluma 2Bond/ glutaraldehyde, Peak Universal Bond/chlorhexidine), and experimental materials or commercial adhesives modified with antimicrobial agents, including materials with quaternary ammonium methacrylate (QAM) [dimethylaminododecyl methacrylate (DMADDM) and dimethylaminohexadecyl methacrylate (DMAHDM)], nanoparticles [silver (NAg), titanium dioxide (TiO2), zinc oxide (ZnO)], silver or zinc doped bioactive active glass (BAG), titanium, copper iodide, and compounds such as triclosan, quercetin, grape seed extract, among others. The use of antimicrobial agents is a favorable perspective for the functionalization of adhesive systems to inhibit secondary caries. However, more clinical studies need to prove the efficacy of these materials

    Schwannoma of the Colon

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    Schwannomas are neoplasms originating from Schwann cells, which are the cells forming nerve sheaths. These neoplasms generally involve peripheral nerves. They rarely affect the gastrointestinal tract and primary colon involvement is extremely rare. The objective of the present paper was to present a case of primary schwannoma of the sigmoid colon, unassociated with von Recklinghausen disease, that was histopathologically confirmed by means of an immunohistochemical panel. The patient was a 71-year-old woman who had had rectal bleeding when evacuating, with pain and tenesmus, for 4 months. She underwent colonoscopy, which identified a raised submucous lesion of 2.8 cm in diameter, located in the sigmoid colon, 30 cm from the anal margin. During examination, loop polypectomy with lesion excision was performed. Histopathological evaluation showed that this was a tumor of stromal origin. Its resection margins were compromised by neoplasia, and colon resection by means of videolaparoscopy was indicated. Conventional histopathological examination using the hematoxylin-eosin technique suggested that the neoplasm was of mesenchymal origin. An immunohistochemical panel was run for etiological confirmation, using anti-CD34 antibodies, desmin, cytokeratins (AE1/AE3), cKit, chromogranin and S-100 protein. The panel showed intense immunoexpression of S-100 protein. Investigation of the proliferative activity rate using Ki-67 antibodies showed that there was a low rate of mitotic activity, thus confirming the diagnosis of primary benign schwannoma of the colon. The patient's postoperative evolution was uneventful and she remains in good health, without signs of tumor recurrence, 15 months after surgical excision

    Gochnatia polymorpha: macro- and microscopic identification of leaf and stem for pharmacognostic quality control

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    AbstractGochnatia polymorpha (Less.) Cabrera, Asteraceae, is popularly known as cambará and cambara-de-folha-grande in Brazil. It is used in traditional medicine to treat respiratory and gastrointestinal disorders. Pharmacological studies revealed antiinflammatory, antispasmodic, antibacterial and antiviral activities. The goal of this paper was to carry out morphological and anatomical studies in order to describe the aerial parts of G. polymorpha. The botanical material was collected, fixed, and prepared according to usual light and scanning electron microtechniques. The leaves are simple, oblong-lanceolate to elliptical-lanceolate in form with mucronate acute apex, rounded base, entire or slightly toothed margin, and short petiole. In transection, the epidermis is uniseriate along the leaf blade. A subepidermal layer next to the adaxial side is present. Anomocytic stomata are seen only on the abaxial surface. Capitate glandular trichomes and T-shaped non-glandular trichomes occur on the leaves. The mesophyll is dorsiventral and minor collateral vascular bundles are enclosed by a sheath of thickwalled parenchymatic cells. The midrib is biconvex and the petiole has a circular shape. The epidermis of the stem consists of a single layer of cells with glandular and nonglandular trichomes. The vascular cylinder shows typical structure and perivascular fiber caps are next to the phloem

    Analysis of the Specificity and Biochemical Characterization of Metalloproteases Isolated from Eupenicillium javanicum Using Fluorescence Resonance Energy Transfer Peptides

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    Enzymes have important features that may facilitate their application in industrial processes and have been used as alternatives to chemical catalysts. In particular, proteases can be isolated from microorganisms, which provide important sources of advantageous enzymes for industrial processes. For example, Eupenicillium javanicum is a filamentous fungus that has been shown to express industrially applicable enzymes and chemical components, such as antifungal compounds. The biotechnological potential of E. javanicum and proteases made us search a novel protease from this microorganism. The macromolecule was isolated, the main biochemical properties was evaluated, and the specificity of the protease subsites was determined. The protease was produced under solid-state bioprocess with wheat bran and isolated by two chromatography steps with yield of 27.5% and 12.4-fold purification. The molecular mass was estimated at 30 kDa. The N-terminal sequence of the first 20 amino acid residues was AVGAGYNASVALALEKALNN. The enzyme presented higher proteolytic activity at pH 6.0 and 60 degrees C. The protease is stable at wide range of pH values and temperatures and in the presence of surfactants. The primed side of the catalytic site showed the highest catalytic efficiency of the enzyme isolated from E. javanicum. The S'(1) subsite is responsible for catalyzing the protease reaction with substrates with tyrosine in P'(1). These findings provide important insights into the biochemical characterization of a highly active protease from E. javanicum and may facilitate the development of industrial processes involving this protease.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2012/24703-8, 2011/06986-0]Univ Sao Paulo, Sch Pharmaceut Sci Ribeirao Preto, Dept Pharmaceut Sci, Ribeirao Preto, BrazilUniv Fed Sao Paulo, Paulista Med Sch, Dept Biophys, Sao Paulo, BrazilUniv Sao Paulo, Sch Pharmaceut Sci Ribeirao Preto, Dept Phys & Chem, Ribeirao Preto, BrazilUniv Fed Sao Paulo, Paulista Med Sch, Dept Biophys, Sao Paulo, BrazilFAPESP: 2012/24703-8FAPESP: 2011/06986-0Web of Scienc

    Outcomes from a 12-Week, Open-Label, Multicenter Clinical Trial of Teduglutide in Pediatric Short Bowel Syndrome

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    Objective To determine safety and pharmacodynamics/efficacy of teduglutide in children with intestinal failure associated with short bowel syndrome (SBS-IF). Study design This 12-week, open-label study enrolled patients aged 1-17 years with SBS-IF who required parenteral nutrition (PN) and showed minimal or no advance in enteral nutrition (EN) feeds. Patients enrolled sequentially into 3 teduglutide cohorts (0.0125 mg/kg/d [n = 8], 0.025 mg/kg/d [n = 14], 0.05 mg/kg/d [n = 15]) or received standard of care (SOC, n = 5). Descriptive summary statistics were used. Results All patients experienced ≥1 treatment-emergent adverse event; most were mild or moderate. No serious teduglutide-related treatment-emergent adverse events occurred. Between baseline and week 12, prescribed PN volume and calories (kcal/kg/d) changed by a median of −41% and −45%, respectively, with 0.025 mg/kg/d teduglutide and by −25% and −52% with 0.05 mg/kg/d teduglutide. In contrast, PN volume and calories changed by 0% and −6%, respectively, with 0.0125 mg/kg/d teduglutide and by 0% and −1% with SOC. Per patient diary data, EN volume increased by a median of 22%, 32%, and 40% in the 0.0125, 0.025, and 0.05 mg/kg/d cohorts, respectively, and by 11% with SOC. Four patients achieved independence from PN, 3 in the 0.05 mg/kg/d cohort and 1 in the 0.025 mg/kg/d cohort. Study limitations included its short-term, open-label design, and small sample size. Conclusions Teduglutide was well tolerated in pediatric patients with SBS-IF. Teduglutide 0.025 or 0.05 mg/kg/d was associated with trends toward reductions in PN requirements and advancements in EN feeding in children with SBS-IF

    Novel genes and sex differences in COVID-19 severity

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    [EN] Here, we describe the results of a genome-wide study conducted in 11 939 coronavirus disease 2019 (COVID-19) positive cases with an extensive clinical information that were recruited from 34 hospitals across Spain (SCOURGE consortium). In sex-disaggregated genome-wide association studies for COVID-19 hospitalization, genome-wide significance (P < 5 × 10−8) was crossed for variants in 3p21.31 and 21q22.11 loci only among males (P = 1.3 × 10−22 and P = 8.1 × 10−12, respectively), and for variants in 9q21.32 near TLE1 only among females (P = 4.4 × 10−8). In a second phase, results were combined with an independent Spanish cohort (1598 COVID-19 cases and 1068 population controls), revealing in the overall analysis two novel risk loci in 9p13.3 and 19q13.12, with fine-mapping prioritized variants functionally associated with AQP3 (P = 2.7 × 10−8) and ARHGAP33 (P = 1.3 × 10−8), respectively. The meta-analysis of both phases with four European studies stratified by sex from the Host Genetics Initiative (HGI) confirmed the association of the 3p21.31 and 21q22.11 loci predominantly in males and replicated a recently reported variant in 11p13 (ELF5, P = 4.1 × 10−8). Six of the COVID-19 HGI discovered loci were replicated and an HGI-based genetic risk score predicted the severity strata in SCOURGE. We also found more SNP-heritability and larger heritability differences by age (<60 or ≥60 years) among males than among females. Parallel genome-wide screening of inbreeding depression in SCOURGE also showed an effect of homozygosity in COVID-19 hospitalization and severity and this effect was stronger among older males. In summary, new candidate genes for COVID-19 severity and evidence supporting genetic disparities among sexes are provided.S

    Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021

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    Background: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. Methods: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. Findings: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. Interpretation: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic

    Electronic structure and competition of phases in Cu-(In,Ga)-Se, Ga-Se and In-Se semiconductors : first-principles calculations based on different exchange-correlation potentials

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    Afin de pouvoir utiliser les nouveaux matériaux semi-conducteurs dans les domaines de l’électronique et de l’optique, il faut parvenir à comprendre leur «structure électronique», ou plus précisément le positionnement des niveaux d’énergie des électrons impliqués dans l’absorption / émission d’un photon. Les propriétés électroniques, sensibles à la composition chimique et à la structure du matériau, sont théoriquement accessibles en résolvant les équations de la mécanique quantique sur ordinateur. Ce travail porte sur des simulations théoriques de la structure électronique de semi-conducteurs binaires constitués d'indium (ou du gallium) et de sélénium, ainsi que de leurs "dérivés" à base de cuivre. La stabilité relative des phases cristallographiques de certains composés In-Se et Ga-Se a été évaluée, ce qui a permis d’expliquer certaines tendances connues et de formuler des prédictions. Les résultats obtenus seront particulièrement utiles dans le domaine du photovoltaïque. Les simulations numériques ont été réalisées dans le cadre de la théorie de la fonctionnelle de la densité (DFT), visant les structures cristallines d'équilibre et les propriétés électroniques de quelques semi-conducteurs binaires ou (pseudo)ternaires à base de Cu, In, Ga et Se. Les systèmes étudiés possèdent la même structure à courte portée (environnement tétraédrique des cations et anions) mais diffèrent à longue portée. Les composés binaires (Ga/In)Se, (Ga/In)2Se3 constituent des références importantes dans les diagrammes de phases des systèmes à base de (Cu, In, Se) et (Cu, Ga, Se), au sein desquels figurent les phases potentiellement utiles dans le domaine du photovoltaïque. Le travail comprend deux chapitres d'introduction et trois chapitres exposant des résultats nouveauxIn order to optimally use new semiconductor materials in electronics or optics, one needs to understand their “electronic structure”, that is, the mutual placement of the electron energy levels concerned by the processes of absorption / emission of a photon. The electronic properties, which depend on the material’s chemical composition and crystal structure, may be assessed by theory via solving quantum-mechanical equations on a computer. The present work deals with theory simulations of electronic structure done for several binary semiconductors consisting of indium (or gallium) and selenium, moreover for their “derivatives” containing copper. As a result, the relative stability of crystallographic phases of some Ga-Se and In-Se compounds has been assessed, explaining the known trends and making predictions. The results are expected to be useful for current works in photovoltaics. The numerical simulations have been performed within the density functional theory (DFT), aimed at the equilibrium crystal structures and electronic characteristics of several binary or (pseudo)ternary semiconductors based on Cu, In, Ga and Se. The compounds under study share similar short-range order features (tetrahedral environment of both cations and anions), differently assembled on a long-range scale. The binary compounds (Ga/In)Se, (Ga/In)2Se3 mark important end points at the phase diagrams of the (Cu,In,Se) and (Cu,Ga,Se) systems that cover a number of phases relevant, e.g., for applications in photovoltaics. The work comprises two chapters of introduction and three outlining novel result

    Structure électronique et compétition de phases dans les semi-conducteurs Cu-(In,Ga)-Se, Ga-Se et In-Se : calculs premiers principes basés sur divers potentiels d'échange-corrélation

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    In order to optimally use new semiconductor materials in electronics or optics, one needs to understand their “electronic structure”, that is, the mutual placement of the electron energy levels concerned by the processes of absorption / emission of a photon. The electronic properties, which depend on the material’s chemical composition and crystal structure, may be assessed by theory via solving quantum-mechanical equations on a computer. The present work deals with theory simulations of electronic structure done for several binary semiconductors consisting of indium (or gallium) and selenium, moreover for their “derivatives” containing copper. As a result, the relative stability of crystallographic phases of some Ga-Se and In-Se compounds has been assessed, explaining the known trends and making predictions. The results are expected to be useful for current works in photovoltaics. The numerical simulations have been performed within the density functional theory (DFT), aimed at the equilibrium crystal structures and electronic characteristics of several binary or (pseudo)ternary semiconductors based on Cu, In, Ga and Se. The compounds under study share similar short-range order features (tetrahedral environment of both cations and anions), differently assembled on a long-range scale. The binary compounds (Ga/In)Se, (Ga/In)2Se3 mark important end points at the phase diagrams of the (Cu,In,Se) and (Cu,Ga,Se) systems that cover a number of phases relevant, e.g., for applications in photovoltaics. The work comprises two chapters of introduction and three outlining novel resultsAfin de pouvoir utiliser les nouveaux matériaux semi-conducteurs dans les domaines de l’électronique et de l’optique, il faut parvenir à comprendre leur «structure électronique», ou plus précisément le positionnement des niveaux d’énergie des électrons impliqués dans l’absorption / émission d’un photon. Les propriétés électroniques, sensibles à la composition chimique et à la structure du matériau, sont théoriquement accessibles en résolvant les équations de la mécanique quantique sur ordinateur. Ce travail porte sur des simulations théoriques de la structure électronique de semi-conducteurs binaires constitués d'indium (ou du gallium) et de sélénium, ainsi que de leurs "dérivés" à base de cuivre. La stabilité relative des phases cristallographiques de certains composés In-Se et Ga-Se a été évaluée, ce qui a permis d’expliquer certaines tendances connues et de formuler des prédictions. Les résultats obtenus seront particulièrement utiles dans le domaine du photovoltaïque. Les simulations numériques ont été réalisées dans le cadre de la théorie de la fonctionnelle de la densité (DFT), visant les structures cristallines d'équilibre et les propriétés électroniques de quelques semi-conducteurs binaires ou (pseudo)ternaires à base de Cu, In, Ga et Se. Les systèmes étudiés possèdent la même structure à courte portée (environnement tétraédrique des cations et anions) mais diffèrent à longue portée. Les composés binaires (Ga/In)Se, (Ga/In)2Se3 constituent des références importantes dans les diagrammes de phases des systèmes à base de (Cu, In, Se) et (Cu, Ga, Se), au sein desquels figurent les phases potentiellement utiles dans le domaine du photovoltaïque. Le travail comprend deux chapitres d'introduction et trois chapitres exposant des résultats nouveau
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