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1.
Int J Med Microbiol ; 314: 151602, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280372

RESUMO

PURPOSE: Fusarium keratitis is a severe infection of the anterior eye, frequently leading to keratoplasty or surgical removal of the affected eye. A major risk factor for infection is the use of contact lenses. Inadequate hygiene precautions and mold-growth permissive storage fluids are important risk factors for fungal keratitis. The aim of this study was to comparatively analyze contact lens storage fluids disinfection efficacy against Fusarium species. METHODS: Eleven commercially available storage fluids were tested. The storage fluids were classified according to their active ingredients myristamidopropyldimethylamine (Aldox), polyhexanide and hydrogen peroxide. Efficacy was tested against isolates belonging to the Fusarium solani and Fusarium oxysporum species complexes as the most common agents of mould keratitis. Tests were carried out based on DIN EN ISO 14729. RESULTS: All Aldox and hydrogen peroxide (H2O2) based fluids were effective against Fusarium spp., while the majority of polyhexanide based storage fluids showed only limited or no antifungal effects. Efficacy of polyhexanide could be restored by the addition of the pH-regulating agent tromethamine - an additive component in one commercially available product. CONCLUSIONS: In summary, the use of Aldox- or hydrogen peroxide-based storage fluids may reduce the risk of Fusarium keratitis, while polyhexanide-based agents largely lack efficacy against Fusarium.


Assuntos
Biguanidas , Lentes de Contato , Infecções Oculares Fúngicas , Fusarium , Ceratite , Propilaminas , Antifúngicos/farmacologia , Peróxido de Hidrogênio/farmacologia , Ceratite/prevenção & controle , Ceratite/microbiologia , Lentes de Contato/microbiologia , Infecções Oculares Fúngicas/microbiologia
2.
Eur Heart J ; 42(39): 4077-4088, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34279021

RESUMO

AIMS: Mental stress substantially contributes to the initiation and progression of human disease, including cardiovascular conditions. We aim to investigate the underlying mechanisms of these contributions since they remain largely unclear. METHODS AND RESULTS: Here, we show in humans and mice that leucocytes deplete rapidly from the blood after a single episode of acute mental stress. Using cell-tracking experiments in animal models of acute mental stress, we found that stress exposure leads to prompt uptake of inflammatory leucocytes from the blood to distinct tissues including heart, lung, skin, and, if present, atherosclerotic plaques. Mechanistically, we found that acute stress enhances leucocyte influx into mouse atherosclerotic plaques by modulating endothelial cells. Specifically, acute stress increases adhesion molecule expression and chemokine release through locally derived norepinephrine. Either chemical or surgical disruption of norepinephrine signalling diminished stress-induced leucocyte migration into mouse atherosclerotic plaques. CONCLUSION: Our data show that acute mental stress rapidly amplifies inflammatory leucocyte expansion inside mouse atherosclerotic lesions and promotes plaque vulnerability.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Modelos Animais de Doenças , Células Endoteliais , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
Plant J ; 99(2): 270-285, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30900785

RESUMO

Compartmentation of photosynthetic reactions between mesophyll and bundle sheath cells is a key feature of C4 photosynthesis and depends on the cell-specific accumulation of major C4 enzymes, such as phosphoenolpyruvate carboxylase 1. The ZmPEPC1 upstream region, which drives light-inducible and mesophyll-specific gene expression in maize, has been shown to keep the same properties when introduced into rice (C3 plant), indicating that rice has the transcription factors (TFs) needed to confer C4 -like gene expression. Using a yeast one-hybrid approach, we identified OsbHLH112, a rice basic Helix-Loop-Helix (bHLH) TF that interacts with the maize ZmPEPC1 upstream region. Moreover, we found that maize OsbHLH112 homologues, ZmbHLH80, and ZmbHLH90, also interact with the ZmPEPC1 upstream region, suggesting that these C4 regulators were co-opted from C3 plants. A transactivation assay in maize mesophyll protoplasts revealed that ZmbHLH80 represses, whereas ZmbHLH90 activates, ZmPEPC1 expression. In addition, ZmbHLH80 was shown to impair the ZmPEPC1 promoter activation caused by ZmbHLH90. We showed that ZmbHLH80 and ZmbHLH90 bind to the same cis-element within the ZmPEPC1 upstream region either as homodimers or heterodimers. The formation of homo- and heterodimers with higher oligomeric forms promoted by ZmbHLH80 may explain its negative effect on gene transcription. Gene expression analysis revealed that ZmbHLH80 is preferentially expressed in bundle sheath cells, whereas ZmbHLH90 does not show a clear cell-specific expression pattern. Altogether, our results led us to propose a model in which ZmbHLH80 contributes to mesophyll-specific ZmPEPC1 gene expression by impairing ZmbHLH90-mediated ZmPEPC1 activation in the bundle sheath cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Proteínas de Plantas/fisiologia , Zea mays/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Técnicas de Sonda Molecular , Oryza/genética , Fotossíntese/genética , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Zea mays/metabolismo
4.
Arch Toxicol ; 91(9): 3051-3064, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28204865

RESUMO

Human data about the potency of ethyl acrylate to evoke sensory irritation is currently not available. Therefore, we conducted an experimental exposure study and the magnitude of chemosensory effects in healthy human volunteers was mathematically modeled by combining the factors current concentration (c) and duration/time (t). In a repeated-measures design, 19 subjects were exposed for 4 h to constant and varying concentrations (including peaks of 5 and 10 ppm) of ethyl acrylate with either a 2.5 or 5 ppm time-weighted average (TWA) concentration. Clean air served as control condition. Nasal lavage fluid, eye blinking frequencies, and rhinomanometry were used as physiological measures of sensory irritation. Several subjective ratings assessed olfactory and trigeminal perceptions. The blinking frequency was significantly increased during the varying 5 ppm condition. Regardless of the TWA concentration, varying exposures caused stronger effects than constant exposures. Our mathematical modeling showed that olfactory perceptions generally decreased over time while ratings of eye irritation increased over time even under the constant 5 ppm condition. Including the current concentration in the mathematical modeling always increased the goodness of fit substantially. The results showed that the intensity of sensory irritation could be predicted best with a complex c × t model. During the 2.5 ppm conditions, only the current concentration predicted the ratings and time-dependent processes could not be observed. However, in both 5 ppm TWA conditions strong eye irritations and increased blinking frequency, only at the end of the 4-h exposures a dose-dependency of these adverse effects was clearly shown.


Assuntos
Acrilatos/toxicidade , Olho/efeitos dos fármacos , Irritantes/toxicidade , Acrilatos/administração & dosagem , Adulto , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Irritantes/administração & dosagem , Masculino , Modelos Teóricos , Líquido da Lavagem Nasal , Odorantes/análise , Rinomanometria , Medição de Risco , Fatores de Tempo
5.
Proc Natl Acad Sci U S A ; 110(14): 5522-7, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23509272

RESUMO

Lifespan in Caenorhabditis elegans, Drosophila, and mice is regulated by conserved signaling networks, including the insulin/insulin-like growth factor 1 (IGF-1) signaling cascade and pathways depending on sirtuins, a family of NAD(+)-dependent deacetylases. Small molecules such as resveratrol are of great interest because they increase lifespan in many species in a sirtuin-dependent manner. However, no endogenous small molecules that regulate lifespan via sirtuins have been identified, and the mechanisms underlying sirtuin-dependent longevity are not well understood. Here, we show that in C. elegans, two endogenously produced small molecules, the dauer-inducing ascarosides ascr#2 and ascr#3, regulate lifespan and stress resistance through chemosensory pathways and the sirtuin SIR-2.1. Ascarosides extend adult lifespan and stress resistance without reducing fecundity or feeding rate, and these effects are reduced or abolished when nutrients are restricted. We found that ascaroside-mediated longevity is fully abolished by loss of SIR-2.1 and that the effect of ascr#2 requires expression of the G protein-coupled receptor DAF-37 in specific chemosensory neurons. In contrast to many other lifespan-modulating factors, ascaroside-mediated lifespan increases do not require insulin signaling via the FOXO homolog DAF-16 or the insulin/IGF-1-receptor homolog DAF-2. Our study demonstrates that C. elegans produces specific small molecules to control adult lifespan in a sirtuin-dependent manner, supporting the hypothesis that endogenous regulation of metazoan lifespan functions, in part, via sirtuins. These findings strengthen the link between chemosensory inputs and conserved mechanisms of lifespan regulation in metazoans and suggest a model for communal lifespan regulation in C. elegans.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Glicolipídeos/metabolismo , Longevidade/fisiologia , Sirtuínas/metabolismo , Estresse Fisiológico/fisiologia , Animais , Caenorhabditis elegans/metabolismo , Floxuridina , Estresse Oxidativo/fisiologia , Receptores Acoplados a Proteínas G/metabolismo
6.
Psychother Res ; 25(1): 32-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24295283

RESUMO

OBJECTIVE: Two patient-focused long-term research projects performed in the German outpatient psychotherapy system are focused on in this article. The TK (Techniker Krankenkasse) project is the first study to evaluate a quality assurance and feedback system with regard to its practical feasibility in German routine care. The other study ("Quality Assurance in Outpatient Psychotherapy in Bavaria"; QS-PSY-BAY) was designed to test a new approach for quality assurance in outpatient psychotherapy using electronic documentation of patient characteristics and outcome parameters. In addition this project provides the opportunity to analyze data on health-related costs for the patients undergoing outpatient psychotherapy. METHOD: Both projects and their results indicating high effect sizes are briefly described. RESULTS: From the perspectives of the research teams, advisory boards and other stakeholders, the experiences with these projects are discussed focusing on obstacles, challenges, difficulties, and benefits in developing and implementing the studies. The triangle collaboration of therapists, researchers, and health insurance companies/health service institutions turned out to be fruitful in both studies. CONCLUSIONS: Despite some controversies between the partners the experiences indicate the importance of practiced-research collaborations to provide relevant information about the delivery of outpatient psychotherapy in the health system.


Assuntos
Comportamento Cooperativo , Pesquisa sobre Serviços de Saúde/normas , Pacientes Ambulatoriais , Psicoterapia/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Alemanha , Humanos
7.
Proc Natl Acad Sci U S A ; 108(12): 4776-81, 2011 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-21383123

RESUMO

The macrocyclic polyketides FK506, FK520, and rapamycin are potent immunosuppressants that prevent T-cell proliferation through initial binding to the immunophilin FKBP12. Analogs of these molecules are of considerable interest as therapeutics in both metastatic and inflammatory disease. For these polyketides the starter unit for chain assembly is (4R,5R)-4,5-dihydroxycyclohex-1-enecarboxylic acid derived from the shikimate pathway. We show here that the first committed step in its formation is hydrolysis of chorismate to form (4R,5R)-4,5-dihydroxycyclohexa-1,5-dienecarboxylic acid. This chorismatase activity is encoded by fkbO in the FK506 and FK520 biosynthetic gene clusters, and by rapK in the rapamycin gene cluster of Streptomyces hygroscopicus. Purified recombinant FkbO (from FK520) efficiently catalyzed the chorismatase reaction in vitro, as judged by HPLC-MS and NMR analysis. Complementation using fkbO from either the FK506 or the FK520 gene cluster of a strain of S. hygroscopicus specifically deleted in rapK (BIOT-4010) restored rapamycin production, as did supplementation with (4R,5R)-4,5-dihydroxycyclohexa-1,5-dienecarboxylic acid. Although BIOT-4010 produced no rapamycin, it did produce low levels of BC325, a rapamycin analog containing a 3-hydroxybenzoate starter unit. This led us to identify the rapK homolog hyg5 as encoding a chorismatase/3-hydroxybenzoate synthase. Similar enzymes in other bacteria include the product of the bra8 gene from the pathway to the terpenoid natural product brasilicardin. Expression of either hyg5 or bra8 in BIOT-4010 led to increased levels of BC325. Also, purified Hyg5 catalyzed the predicted conversion of chorismate into 3-hydroxybenzoate. FkbO, RapK, Hyg5, and Bra8 are thus founder members of a previously unrecognized family of enzymes acting on chorismate.


Assuntos
Proteínas de Bactérias , Ácido Corísmico/metabolismo , Genes Bacterianos/fisiologia , Imunossupressores/metabolismo , Família Multigênica/fisiologia , Sirolimo/metabolismo , Streptomyces , Tacrolimo/análogos & derivados , Tacrolimo/metabolismo , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Ácido Corísmico/química , Imunossupressores/química , Sirolimo/química , Streptomyces/enzimologia , Streptomyces/genética , Tacrolimo/química
8.
Trends Microbiol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493013

RESUMO

The natural process of evolutionary adaptation is often exploited as a powerful tool to obtain microbes with desirable traits. For industrial microbes, evolutionary engineering is often used to generate variants that show increased yields or resistance to stressful industrial environments, thus obtaining superior microbial cell factories. However, even in large populations, the natural supply of beneficial mutations is typically low, which implies that obtaining improved microbes is often time-consuming and inefficient. To overcome this limitation, different techniques have been developed that boost mutation rates. While some of these methods simply increase the overall mutation rate across a genome, others use recent developments in DNA synthesis, synthetic biology, and CRISPR-Cas techniques to control the type and location of mutations. This review summarizes the most important recent developments and methods in the field of evolutionary engineering in model microorganisms. It discusses how both in vitro and in vivo approaches can increase the genetic diversity of the host, with a special emphasis on in vivo techniques for the optimization of metabolic pathways for precision fermentation.

9.
Nat Commun ; 15(1): 1112, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326309

RESUMO

Microbes are increasingly employed as cell factories to produce biomolecules. This often involves the expression of complex heterologous biosynthesis pathways in host strains. Achieving maximal product yields and avoiding build-up of (toxic) intermediates requires balanced expression of every pathway gene. However, despite progress in metabolic modeling, the optimization of gene expression still heavily relies on trial-and-error. Here, we report an approach for in vivo, multiplexed Gene Expression Modification by LoxPsym-Cre Recombination (GEMbLeR). GEMbLeR exploits orthogonal LoxPsym sites to independently shuffle promoter and terminator modules at distinct genomic loci. This approach facilitates creation of large strain libraries, in which expression of every pathway gene ranges over 120-fold and each strain harbors a unique expression profile. When applied to the biosynthetic pathway of astaxanthin, an industrially relevant antioxidant, a single round of GEMbLeR improved pathway flux and doubled production titers. Together, this shows that GEMbLeR allows rapid and efficient gene expression optimization in heterologous biosynthetic pathways, offering possibilities for enhancing the performance of microbial cell factories.


Assuntos
Recombinases , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Recombinases/metabolismo , Vias Biossintéticas/genética , Edição de Genes , Expressão Gênica , Engenharia Metabólica
10.
Nat Commun ; 15(1): 1113, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326330

RESUMO

Site-specific recombinases such as the Cre-LoxP system are routinely used for genome engineering in both prokaryotes and eukaryotes. Importantly, recombinases complement the CRISPR-Cas toolbox and provide the additional benefit of high-efficiency DNA editing without generating toxic DNA double-strand breaks, allowing multiple recombination events at the same time. However, only a handful of independent, orthogonal recombination systems are available, limiting their use in more complex applications that require multiple specific recombination events, such as metabolic engineering and genetic circuits. To address this shortcoming, we develop 63 symmetrical LoxP variants and test 1192 pairwise combinations to determine their cross-reactivity and specificity upon Cre activation. Ultimately, we establish a set of 16 orthogonal LoxPsym variants and demonstrate their use for multiplexed genome engineering in both prokaryotes (E. coli) and eukaryotes (S. cerevisiae and Z. mays). Together, this work yields a significant expansion of the Cre-LoxP toolbox for genome editing, metabolic engineering and other controlled recombination events, and provides insights into the Cre-LoxP recombination process.


Assuntos
Integrases , Recombinação Genética , Integrases/genética , Integrases/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Recombinases/metabolismo , DNA/metabolismo
11.
Nat Commun ; 14(1): 3389, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296137

RESUMO

The generation of genetic diversity via mutagenesis is routinely used for protein engineering and pathway optimization. Current technologies for random mutagenesis often target either the whole genome or relatively narrow windows. To bridge this gap, we developed CoMuTER (Confined Mutagenesis using a Type I-E CRISPR-Cas system), a tool that allows inducible and targetable, in vivo mutagenesis of genomic loci of up to 55 kilobases. CoMuTER employs the targetable helicase Cas3, signature enzyme of the class 1 type I-E CRISPR-Cas system, fused to a cytidine deaminase to unwind and mutate large stretches of DNA at once, including complete metabolic pathways. The tool increases the number of mutations in the target region 350-fold compared to the rest of the genome, with an average of 0.3 mutations per kilobase. We demonstrate the suitability of CoMuTER for pathway optimization by doubling the production of lycopene in Saccharomyces cerevisiae after a single round of mutagenesis.


Assuntos
Proteínas Associadas a CRISPR , Edição de Genes , Sistemas CRISPR-Cas/genética , Mutagênese/genética , Mutação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas Associadas a CRISPR/metabolismo
12.
Cells ; 12(18)2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37759464

RESUMO

The lack of optimal models to evaluate novel agents is delaying the development of effective immunotherapies against human breast cancer (BC). In this prospective open label study, we applied neoadjuvant intratumoral immunotherapy with empty cowpea mosaic virus-like particles (eCPMV) to 11 companion dogs diagnosed with canine mammary cancer (CMC), a spontaneous tumor resembling human BC. We found that two neoadjuvant intratumoral eCPMV injections resulted in tumor reduction in injected tumors in all patients and in noninjected tumors located in the ipsilateral and contralateral mammary chains of injected dogs. Tumor reduction was independent of clinical stage, tumor size, histopathologic grade, and tumor molecular subtype. RNA-seq-based analysis of injected tumors indicated a decrease in DNA replication activity and an increase in activated dendritic cell infiltration in the tumor microenvironment. Immunohistochemistry analysis demonstrated significant intratumoral increases in neutrophils, T and B lymphocytes, and plasma cells. eCPMV intratumoral immunotherapy demonstrated antitumor efficacy without any adverse effects. This novel immunotherapy has the potential for improving outcomes for human BC patients.


Assuntos
Neoplasias da Mama , Comovirus , Humanos , Animais , Cães , Feminino , Terapia Neoadjuvante , Estudos Prospectivos , Neoplasias da Mama/terapia , Imunoterapia , Microambiente Tumoral
13.
Arch Toxicol ; 86(2): 195-203, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21892705

RESUMO

Currently, twelve validated genetic variants have been identified that are associated with urinary bladder cancer (UBC) risk. However, those validated variants explain only 5-10% of the overall inherited risk. In addition, there are more than 100 published polymorphisms still awaiting validation or disproval. A particularly promising of the latter unconfirmed polymorphisms is rs2854744 that recently has been published to be associated with UBC risk. The [A] allele of rs2854744 has been reported to be associated with a higher promoter activity of the insulin-like growth factor-binding protein-3 (IGFBP3) gene, which may lead to increased IGFBP-3 plasma levels and cancer risk. Therefore, we investigated the association of rs2854744 with UBC in the IfADo case-control series consisting of 1,450 cases and 1,725 controls from Germany, Hungary, Venezuela and Pakistan. No significant association of rs2854744 with UBC risk was obtained (all study groups combined: unadjusted P = 0.4446; adjusted for age, gender and smoking habits P = 0.6510), besides a small effect of the [A] allele in the Pakistani study group opposed to the original findings (unadjusted P = 0.0508, odds ratio (OR) = 1.43 for the multiplicative model) that diminished after adjustment for age, gender and smoking habits (P = 0.7871; OR = 0.93). Associations of rs2854744 with occupational exposure to urinary bladder carcinogens and smoking habits were also not present. A meta-analysis of all available case-control series including the original discovery study resulted in an OR of 1.00 (P = 0.9562). In conclusion, we could not confirm the recently published hypothesis that rs2854744 in the IGFBP3 gene is associated with UBC risk.


Assuntos
Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Neoplasias da Bexiga Urinária/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença/etnologia , Alemanha , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Paquistão , Polimorfismo de Nucleotídeo Único , Neoplasias da Bexiga Urinária/etnologia , Venezuela
14.
Arch Toxicol ; 86(9): 1369-78, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22532026

RESUMO

Recently, rs11892031[A] has been identified in a genome-wide association study (GWAS) to confer increased risk of urinary bladder cancer (UBC). To confirm this association and additionally study a possible relevance of exposure to urinary bladder carcinogens, we investigated the IfADo UBC study group, consisting of eight case-control series from different regions including 1,805 cases and 2,141 controls. This analysis was supplemented by a meta-analysis of all published data, including 13,395 cases and 54,876 controls. Rs11892031 A/A was significantly associated with UBC risk in the IfADo case-control series adjusted to cigarette smoking, gender, age and ethnicity (OR = 1.18; 95% CI = 1.02-1.37; P = 0.026). In the meta-analysis, a convincing association with UBC risk was obtained (OR = 1.19; 95% Cl = 1.12-1.26; P < 0.0001). Interestingly, the highest odds ratios were obtained for individual case-control series with a high degree of occupational exposure to polycyclic aromatic hydrocarbons and aromatic amines: cases with suspected occupational UBC (OR = 1.41) and cases from the highly industrialized Ruhr area (OR = 1.98) compared with Ruhr area controls (all combined OR = 1.46). Odds ratios were lower for study groups with no or a lower degree of occupational exposure to bladder carcinogens, such as the Hungary (OR = 1.02) or the ongoing West German case-control series (OR = 1.06). However, the possible association of rs11892031[A] with exposure to bladder carcinogens still should be interpreted with caution, because in contrast to the differences between the individual study groups, interview-based data on occupational exposure were not significantly associated with rs11892031. In conclusion, the association of rs11892031[A] with UBC risk could be confirmed in independent study groups.


Assuntos
Carcinógenos Ambientais/toxicidade , Cromossomos Humanos Par 2/genética , Loci Gênicos , Glucuronosiltransferase/genética , Polimorfismo de Nucleotídeo Único , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/genética , Animais , Carcinógenos Ambientais/administração & dosagem , Carcinógenos Ambientais/farmacocinética , Estudos de Associação Genética , Predisposição Genética para Doença , Glucuronosiltransferase/metabolismo , Humanos , Inativação Metabólica , Íntrons , Isoenzimas/genética , Isoenzimas/metabolismo , Família Multigênica , Exposição Ocupacional , Risco , Fumar/efeitos adversos , Toxicogenética/métodos , Neoplasias da Bexiga Urinária/metabolismo
15.
J Toxicol Environ Health A ; 75(8-10): 582-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22686319

RESUMO

Chronic inhalation of quartz-containing dust produces reversible inflammatory changes in lungs resulting in irreversible fibrotic changes termed pneumoconiosis. Due to the inflammatory process in the lungs, highly reactive substances are released that may be detoxified by glutathione S-transferases. Therefore, 90 hard coal miners with pneumoconiosis as a recognized occupational disease (in Germany: Berufskrankheit BK 4101) were genotyped for glutathione S-transferases M1 (GSTM1) and T1 (GSTT1) according to standard methods. Furthermore, occupational exposure and smoking habits were assessed by questionnaire. Changes in a chest x-ray were classified according to ILO classification 2000. Of the investigated hard coal miners 43% were GSTM1 negative whereas 57% were GSTM1 positive. The arithmetic mean of the age at time of investigation was 74.2 yr (range: 42-87 yr). Seventy-four percent of the hard coal miners reported being ever smokers, while 26% denied smoking. All hard coal miners provided pneumoconiosis-related changes in the chest x-ray. The observed frequency of GSTM1 negative hard coal miners was not different from frequencies reported for general Caucasian populations and in agreement with findings reported for Chinese coal miners. In contrast, in a former study, 16 of 19 German hard coal miners (84%) with urinary bladder cancer displayed a GSTM1 negative genotype. The outcome of this study provides evidence that severely occupationally exposed Caucasian hard coal miners do not present an elevated level of GSTM1 negative individuals.


Assuntos
Antracose/genética , Minas de Carvão , Glutationa Transferase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA/genética , Genótipo , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Fumar/efeitos adversos , População Branca , Indenização aos Trabalhadores
16.
Pharmacogenet Genomics ; 21(10): 673-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21750470

RESUMO

Genotyping N-acetyltransferase 2 (NAT2) is of high relevance for individualized dosing of antituberculosis drugs and bladder cancer epidemiology. In this study we compared a recently published tagging single nucleotide polymorphism (SNP) (rs1495741) to the conventional 7-SNP genotype (G191A, C282T, T341C, C481T, G590A, A803G and G857A haplotype pairs) and systematically analysed if novel SNP combinations outperform the latter. For this purpose, we studied 3177 individuals by PCR and phenotyped 344 individuals by the caffeine test. Although the tagSNP and the 7-SNP genotype showed a high degree of correlation (R=0.933, P<0.0001) the 7-SNP genotype nevertheless outperformed the tagging SNP with respect to specificity (1.0 vs. 0.9444, P=0.0065). Considering all possible SNP combinations in a receiver operating characteristic analysis we identified a 2-SNP genotype (C282T, T341C) that outperformed the tagging SNP and was equivalent to the 7-SNP genotype. The 2-SNP genotype predicted the correct phenotype with a sensitivity of 0.8643 and a specificity of 1.0. In addition, it predicted the 7-SNP genotype with sensitivity and specificity of 0.9993 and 0.9880, respectively. The prediction of the NAT2 genotype by the 2-SNP genotype performed similar in populations of Caucasian, Venezuelan and Pakistani background. A 2-SNP genotype predicts NAT2 phenotypes with similar sensitivity and specificity as the conventional 7-SNP genotype. This procedure represents a facilitation in individualized dosing of NAT2 substrates without losing sensitivity or specificity.


Assuntos
Arilamina N-Acetiltransferase/genética , Cafeína/farmacologia , Acetilação , Estudos de Casos e Controles , Etnicidade/genética , Feminino , Genótipo , Técnicas de Genotipagem/métodos , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Sensibilidade e Especificidade
17.
Inflamm Res ; 60(12): 1153-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21912978

RESUMO

OBJECTIVE: Histamine plays a role in several (patho) physiological processes that are commonly studied in mouse models. However, a systematic quantification of histamine and its metabolite N-methylhistamine in mouse organs has not been reported so far. METHODS: Balb/c and C57Bl/6 mice were grouped according to their sex and age. Brains, hearts, lungs, livers, kidneys, stomachs, intestines, thymi, spleens, and lymph nodes were excised, weighed, and homogenized. Histamine and N-methylhistamine were quantified simultaneously by a HPLC-mass spectrometry method. RESULTS: In all organs analyzed, histamine and N-methylhistamine were detected; however, with quantitative differences. Histamine was present most abundantly in the stomach, lymph nodes, and thymus. The lowest histamine concentrations were detected in brain, liver, lung, and intestine. In most organs, the histamine concentrations increased age-dependently. Substantial concentrations of N-methylhistamine were detected only in lung, intestine and kidney, while in all other organs it was present only in minor quantities. CONCLUSION: HPLC-mass spectrometry is a useful method for the highly sensitive and simultaneous detection of histamine and N-methylhistamine. Histamine is present in virtually all organs, not only in those traditionally associated with histamine-mediated disease. Highest concentrations are found in stomach, lymph node, and thymus; medium concentrations in heart, spleen, and kidney; and lowest concentrations detected in intestine, brain, liver, and lung.


Assuntos
Histamina/análise , Metilistaminas/análise , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Animais , Química Encefálica , Cromatografia Líquida de Alta Pressão , Feminino , Intestinos/química , Rim/química , Fígado/química , Pulmão/química , Linfonodos/química , Masculino , Camundongos , Miocárdio/química , Baço/química , Estômago/química , Espectrometria de Massas em Tandem , Timo/química
18.
Vet Sci ; 8(11)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34822633

RESUMO

Hand hygiene (HH) is the most important measure to prevent nosocomial infections. HH compliance in companion animal clinics has been reported to be poor. The present study compared an online application with the WHO evaluation form to assess the WHO five moments of HH in a Swiss companion animal clinic. In 202 hand swabs from 87 staff members, total viable count (TVC) before and after patient contact was evaluated and the swabs were tested for selected antimicrobial resistant microorganisms of public health importance. HH compliance (95% confidence interval) was 36.6% (33.8-39.5%) and was similar when assessed with the two evaluation tools. HH differed between hospital areas (p = 0.0035) and HH indications (p < 0.0001). Gloves were worn in 22.0% (18.0-26.6%) of HH observations and were indicated in 37.2% (27.3-48.3%) of these observations. Mean TVC before patient contact was lower (0.52 log CFU/cm2) than after patient contact (1.02 log CFU/cm2) but was similar before patient contact on gloved and ungloved hands. Three hand swabs (1.5% (0.4-4.3%)) were positive for methicillin-resistant Staphylococcus aureus. Gloving should not be regarded as a substitute for HH. Overall, HH in companion animal medicine should urgently be fostered.

19.
J Fungi (Basel) ; 7(7)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206899

RESUMO

Fungal eye infections can lead to loss of vision and blindness. The disease is most prevalent in the tropics, although case numbers in moderate climates are increasing as well. This study aimed to determine the dominating filamentous fungi causing eye infections in Germany and their antifungal susceptibility profiles in order to improve treatment, including cases with unidentified pathogenic fungi. As such, we studied all filamentous fungi isolated from the eye or associated materials that were sent to the NRZMyk between 2014 and 2020. All strains were molecularly identified and antifungal susceptibility testing according to the EUCAST protocol was performed for common species. In total, 242 strains of 66 species were received. Fusarium was the dominating genus, followed by Aspergillus, Purpureocillium, Alternaria, and Scedosporium. The most prevalent species in eye samples were Fusarium petroliphilum, F. keratoplasticum, and F. solani of the Fusarium solani species complex. The spectrum of species comprises less susceptible taxa for amphotericin B, natamycin, and azoles, including voriconazole. Natamycin is effective for most species but not for Aspergillus flavus or Purpureocillium spp. Some strains of F. solani show MICs higher than 16 mg/L. Our data underline the importance of species identification for correct treatment.

20.
Front Plant Sci ; 12: 559967, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33897718

RESUMO

Spatial separation of the photosynthetic reactions is a key feature of C4 metabolism. In most C4 plants, this separation requires compartmentation of photosynthetic enzymes between mesophyll (M) and bundle sheath (BS) cells. The upstream region of the gene encoding the maize PHOSPHOENOLPYRUVATE CARBOXYLASE 1 (ZmPEPC1) has been shown sufficient to drive M-specific ZmPEPC1 gene expression. Although this region has been well characterized, to date, only few trans-factors involved in the ZmPEPC1 gene regulation were identified. Here, using a yeast one-hybrid approach, we have identified three novel maize transcription factors ZmHB87, ZmCPP8, and ZmOrphan94 as binding to the ZmPEPC1 upstream region. Bimolecular fluorescence complementation assays in maize M protoplasts unveiled that ZmOrphan94 forms homodimers and interacts with ZmCPP8 and with two other ZmPEPC1 regulators previously reported, ZmbHLH80 and ZmbHLH90. Trans-activation assays in maize M protoplasts unveiled that ZmHB87 does not have a clear transcriptional activity, whereas ZmCPP8 and ZmOrphan94 act as activator and repressor, respectively. Moreover, we observed that ZmOrphan94 reduces the trans-activation activity of both activators ZmCPP8 and ZmbHLH90. Using the electromobility shift assay, we showed that ZmOrphan94 binds to several cis-elements present in the ZmPEPC1 upstream region and one of these cis-elements overlaps with the ZmbHLH90 binding site. Gene expression analysis revealed that ZmOrphan94 is preferentially expressed in the BS cells, suggesting that ZmOrphan94 is part of a transcriptional regulatory network downregulating ZmPEPC1 transcript level in the BS cells. Based on both this and our previous work, we propose a model underpinning the importance of a regulatory mechanism within BS cells that contributes to the M-specific ZmPEPC1 gene expression.

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