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1.
Waste Manag ; 178: 301-310, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38422683

RESUMO

While near-infrared (NIR) spectroscopy in post-consumer waste electrical and electronic equipment (WEEE) recycling accurately separates white or clear polymers, 40% containing dark plastics, termed 'unsortable WEEE,' are excluded from sorting lines and therefore incinerated or landfilled, causing environmental concerns. This study investigates the potential of using non-reactive and reactive copolymers as compatibilizers to enhance the performance of unsortable WEEE plastics free of brominated flame retardants. To the best of our knowledge, this is the first time that such copolymers have been explored as a solution for improving the compatibility of unsortable WEEE polymer blends. Initial trials with 4% of styrene-ethylene-butylene-styrene copolymer (SEBS-13) and SEBS-30-g-(maleic anhydride) copolymer (SEBS-30-g-MA MA) as compatibilizers showed insufficient results compared to virgin commercial polymers. However, the addition of higher concentrations of compatibilizers (i.e. up to 20 wt%) and the use of a SEBS having a higher styrene content (i.e. SEBS-30) improved the mechanical properties of the material, causing it to transition from brittle to ductile. This behavior was found more pronounced for the 20% non-reactive SEBS-30, for which the SEM analysis showed reduced phase segregation and revealed a more homogeneous fracture surface. This was further supported by Differential Scanning Calorimetry (DSC) analysis, which showed evidence of an interaction between one or more polymer phases. With a room temperature performance equivalent to that of virgin conventional polymers, the SEBS-30 compatibilization approach has made it possible to consider using unsortable WEEE streams as recycled materials in commercial applications.


Assuntos
Resíduo Eletrônico , Resíduo Eletrônico/análise , Plásticos/análise , Reciclagem/métodos , Polímeros , Poliestirenos/análise
2.
Mol Microbiol ; 80(4): 1102-19, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21435032

RESUMO

We identified a genetic context encoding a transcriptional regulator of the Rgg family and a small hydrophobic peptide (SHP) in nearly all streptococci and suggested that it may be involved in a new quorum-sensing mechanism, with SHP playing the role of a pheromone. Here, we provide further support for this hypothesis by constructing a phylogenetic tree of the Rgg and Rgg-like proteins from Gram-positive bacteria and by studying the shp/rgg1358 locus of Streptococcus thermophilus LMD-9. We identified the shp1358 gene as a target of Rgg1358, and used it to confirm the existence of the steps of a quorum-sensing mechanism including secretion, maturation and reimportation of the pheromone into the cell. We used surface plasmon resonance to demonstrate interaction between the pheromone and the regulatory protein and performed electrophoretic mobility shift assays to assess binding of the transcriptional regulator to the promoter regions of its target genes. The active form of the pheromone was identified by mass spectrometry. Our findings demonstrate that the shp/rgg1358 locus encodes two components of a novel quorum-sensing mechanism involving a transcriptional regulator of the Rgg family and a SHP pheromone that is detected and reimported into the cell by the Ami oligopeptide transporter.


Assuntos
Proteínas de Bactérias/metabolismo , Feromônios/metabolismo , Percepção de Quorum , Streptococcaceae/metabolismo , Transativadores/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA , Ensaio de Desvio de Mobilidade Eletroforética , Regulação Bacteriana da Expressão Gênica , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas , Filogenia , Regiões Promotoras Genéticas , Análise de Sequência de DNA , Transdução de Sinais , Streptococcaceae/química , Streptococcaceae/genética , Ressonância de Plasmônio de Superfície , Transativadores/química , Transativadores/genética , Transcrição Gênica
3.
Rev Stomatol Chir Maxillofac ; 112(2): 101-6, 2011 Apr.
Artigo em Francês | MEDLINE | ID: mdl-20688347

RESUMO

In relation with the structured pattern of crime today, and owing to the evolution observed among sciences and techniques, the legal system more and more frequently requires expert advice in numerous criminal cases with increasing technicality. The expert and the investigating officer appear to be of equal importance regarding the advices on which the judge bases both his evidence appreciation and his judgement when giving a ruling on a suspect's potential culpability.


Assuntos
Direito Penal , Prova Pericial , Ciências Forenses , Direito Penal/legislação & jurisprudência , Direito Penal/normas , Prova Pericial/legislação & jurisprudência , Prova Pericial/normas , Psiquiatria Legal/legislação & jurisprudência , Psiquiatria Legal/normas , Ciências Forenses/legislação & jurisprudência , Ciências Forenses/normas , França , Humanos , Função Jurisdicional , Competência Profissional , Delitos Sexuais/legislação & jurisprudência , Responsabilidade Social
4.
J Neural Transm (Vienna) ; 116(6): 699-702, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19023641

RESUMO

Since little is known concerning regulation of immunological parameters in rapid changing psychiatric states like panic attacks, we measured cytokines at different time points in healthy subjects, which underwent experimental panic induction using the CCK-4 paradigm. Apart from a challenge related IL-6 increase, we could not observe any changes of neuroimmunological markers in relation to acute anxiety with regard to time and group. Herein we conducted for the first time a new approach to immunological research in panic disorder, suggesting immune changes are more related to long term disease stress.


Assuntos
Biomarcadores/sangue , Interleucina-6/sangue , Transtorno de Pânico/sangue , Transtorno de Pânico/imunologia , Adulto , Humanos , Interleucina-6/imunologia , Masculino , Transtorno de Pânico/induzido quimicamente , Tetragastrina/toxicidade
5.
Am J Med Genet ; 76(3): 229-37, 1998 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-9508242

RESUMO

We describe a five-generation kindred with familial eosinophilia (FE; MIM131400), characterized by the occurrence of sustained eosinophilia of unidentifiable cause in multiple relatives. The inheritance pattern is consistent with an autosomal dominant pattern. Among 52 related subjects studied, 19 were affected and 33 were unaffected. Ten unaffected spouses were also evaluated. Four subjects with sustained eosinophilia were diagnosed with cardiac abnormalities and two of them also had neurologic symptoms. In comparison with the unaffected or spouses, evaluation of complete blood counts showed that the affected relatives had, as expected, significantly higher white cell (P < 0.005) and absolute eosinophil counts (P < 0.001) and lower red cell counts (P < 0.05). Evaluation of serum cytokine levels (IL-5, IL-3, and granulocyte-macrophage colony-stimulating factor (GMCSF) and serology for parasitic helminth infection demonstrated no differences between the affected and unaffected individuals; no individuals studied had serologic evidence for parasitic infection. There were also no differences in anti-nuclear antibody, serum cobalamin (vitamin B12) level, immunoglobulin level, leukocyte alkaline phosphatase, rheumatoid factor, HLA analysis, and stool findings for ova and parasites. Among eight affected persons who had peripheral blood or bone marrow karyotype analysis, two carried the same chromosome abnormality, a pericentric inversion of chromosome 10, inv (10) (p11.2q21.2). A gene mapping study is currently underway to study the underlying genetic mechanism(s) of this syndrome.


Assuntos
Aberrações Cromossômicas/genética , Eosinofilia/genética , Adolescente , Adulto , Idoso , Anticorpos Anti-Helmínticos/análise , Criança , Bandeamento Cromossômico , Transtornos Cromossômicos , Inversão Cromossômica , Cromossomos Humanos Par 10 , Características da Família , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Humanos , Interleucina-3/sangue , Interleucina-5/sangue , Cariotipagem , Masculino , Pessoa de Meia-Idade , Linhagem , Estados Unidos
6.
Leuk Lymphoma ; 42(1-2): 99-108, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11699227

RESUMO

In an ongoing study, families with two or more living cases of B-CLL in first-degree relatives have been recruited through physician and self-referral. Since 1967, 28 kindreds with 73 cases of B-CLL have been enrolled within the National Cancer Institute (NCI) Familial B-CLL Registry. Medical, clinical, and demographic information have been obtained from private physicians, patient interview, hospital records, and death certificates. We used SEER Registry data to compare characteristics of sporadic B-CLL to familial B-CLL. The mean age at diagnosis was approximately 10 years younger among familial cases (57.9 +/- 12.1) than that observed in sporadic cases (70.1 +/- 11.9). A higher percentage of second primary tumors among familial CLL cases compared to reports in sporadic was also observed (16% vs. 8.8%). However, the transformation rate to non-Hodgkin's lymphoma does not appear to be different from that reported for sporadic cases. In conclusion, we observed some differences between familial and sporadic cases; whether any of these characteristics affect survival time or severity of disease is unknown. The study of families with multiple B-CLL cases will aid in delineating the genes and environmental factors that may play a role in the development of both forms of B-CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Sistema de Registros/estatística & dados numéricos , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica , Saúde da Família , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/epidemiologia , Estudos Longitudinais , Linfoma não Hodgkin , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Segunda Neoplasia Primária , Linhagem , Remissão Espontânea , Estados Unidos
7.
Int Migr Rev ; 29(4): 1,041-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-12291222

RESUMO

"This article addresses the way in which the Province of Quebec has obtained increasing power in the area of immigration.... Data from interviews with key members of [the Ministry of Immigration] and from selected documents are drawn on to illustrate Quebec's cultural politics. The Quebec position on the question of immigration as it has evolved in the context of immigration policies defined by the federal government in Ottawa is examined.... In particular, the present article considers how attempts to construct a cultural identity and a nation-state in Quebec have had important consequences for immigration policy and for attitudes and policies concerning Quebec's cultural minorities. The emergence of the notion of 'cultural communities' as a result of the constitutional rivalry and the on-going struggle for legitimacy between Quebec and Ottawa is also explored."


Assuntos
Atitude , Cultura , Emigração e Imigração , Grupos Minoritários , Política , Política Pública , América , Comportamento , Canadá , Demografia , Países Desenvolvidos , América do Norte , População , Características da População , Dinâmica Populacional , Psicologia
17.
Scand J Rheumatol ; 35(1): 20-2, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16467036

RESUMO

OBJECTIVE: CD14, the monocyte receptor for lipopolysaccharides (LPS), is an important mediator of inflammatory processes. As the T-159C exchange in the promotor of the CD14 gene was reported to lead to enhanced CD14 expression, this could be a new susceptibility gene for rheumatoid arthritis (RA). We investigated whether this single nucleotide polymorphism (SNP) serves as a risk factor for disease development or has any influence on serological activity parameters of RA or soluble CD14 (sCD14) levels. PATIENTS AND METHODS: A total of 130 patients with RA, diagnosed according to the revised American College of Rheumatology (ACR) criteria, and 130 healthy subjects, all Caucasians, were genotyped using polymerase chain reaction (PCR). Genotype frequencies were compared by chi2 analysis. RESULTS: Forty (31%) patients vs. 39 (30%) controls were genotyped CC; 71 (55%) vs. 67 (52%) were heterozygous, and 19 (15%) vs. 24 (19%) showed the TT genotype (p = 0.7). Accordingly, the allele frequency was equally distributed (p = 0.8). There was also no significant difference in genotype distribution between subgroups of patients categorized according to serological activity parameters and sCD14 levels. CONCLUSION: We found no association between the CD14/C-159T polymorphism and increased risk for the development of RA or serological disease activity parameters or sCD14 levels.


Assuntos
Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Receptores de Lipopolissacarídeos/genética , Polimorfismo de Nucleotídeo Único , Antígenos CD/genética , Predisposição Genética para Doença , Genótipo , Humanos , Valores de Referência , População Branca
18.
Anaesthesist ; 35(8): 465-72, 1986 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-3777408

RESUMO

Using the afterload-independent end-systolic pressure-dimension-relationship a study was performed in order to investigate whether there are differences in the negative inotropic effects of halothane, enflurane and isoflurane at 1 MAC in 70% N2O. 30 patients of ASA-groups I and II were studied. Using transoesophageal 2d- and m-mode echocardiography the end-systolic-pressure-dimension-relationship was established and the slope (parameter of contractility) determined. The slope decreased significantly (paired Wilcoxon-test 2 alpha less than 0.01) with halothane (68.5/46.5 mmHg/cm), enflurane (56/48 mm Hg/cm) and isoflurane (63/35 mmHg/cm). There is no difference between the three groups (Kruskal-Wallis-test 2 alpha greater than 0.05). The negative inotropic effects of halothane, enflurane and isoflurane at 1 MAC in 70% N2O are the same. The vasodilation caused by isoflurane enables better pump function compared to halothane and enflurane, but may cause severe hypotension. We conclude that for cardiac risk patients isoflurane has no outstanding advantages in comparison to halothane and enflurane.


Assuntos
Enflurano/efeitos adversos , Halotano/efeitos adversos , Isoflurano/efeitos adversos , Contração Miocárdica/efeitos dos fármacos , Adulto , Anestesia , Pressão Sanguínea/efeitos dos fármacos , Depressão Química , Ecocardiografia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Medicação Pré-Anestésica
19.
Anal Biochem ; 298(2): 246-52, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11700979

RESUMO

A general method for RNA measurement, based on chemical labeling of RNA with digoxigenin (without retrotranscription), has been established. Labeled RNA is hybridized with nylon membranes containing spot blots of PCR-amplified gene fragments and the fluorescence detection is mediated via specific anti-digoxigenin antibody coupled to alkaline phosphatase. The method was optimized in order to be quantitative, and high precision (less than 24% error) was obtained, allowing analysis of relatively small changes in gene expression. When the quantity of cellular RNA used in this method is maintained constant and the amount of RNA in the cell determined, the true intracellular transcript concentrations can be determined, rather than simple abundance of a messenger in RNA population. This RNA quantification technique was extended to macroarrays blotted automatically and the validity of the method was tested by comparison with expression data obtained by Northern blotting.


Assuntos
Clostridium/genética , Clostridium/metabolismo , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , RNA Bacteriano/análise , Northern Blotting , Desoxirribonuclease I/metabolismo , Digoxigenina/metabolismo , Fluorescência , Perfilação da Expressão Gênica , Membranas Artificiais , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , RNA Bacteriano/metabolismo
20.
Int J Clin Monit Comput ; 4(4): 243-8, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3119748

RESUMO

The peak-systolic pressure end-systolic diameter relationship (PSPESDRS) was determined in ten healthy subjects under general anaesthesia by using the radial artery pressure tracing (peak-systolic pressure) and transoesophageal 2d-and m-mode echocardiography (left ventricular diameters) without blocking of autonomic reflexes. Left ventricular load was changed by injection of a single intravenous dose of 0.2 mg nitroglycerin (NTG). Linear regression analysis showed a close linear relationship during the pressure decrease between peak-systolic pressures and end-systolic diameters. During infusion of dobutamine 5 micrograms/kg/min there was also a close linear relationship during pressure decrease with increased slope and unchanged Do (D0 = diameter at theoretical pressure zero). Values taken during pressure returning to control level were shifted leftward indicating transient increased contractility. We conclude, that the PSPESDRS can reliably be measured in humans without autonomic blockade during the decrease of arterial pressure after NTG, where reflex changes in inotropy are not yet present. This relationship increases in slope with dobutamine, reflecting the increased contractile state.


Assuntos
Contração Miocárdica , Pressão Sanguínea/efeitos dos fármacos , Dobutamina , Ecocardiografia/métodos , Esôfago , Frequência Cardíaca/efeitos dos fármacos , Ventrículos do Coração/anatomia & histologia , Humanos , Nitroglicerina
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