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1.
Virus Genes ; 57(2): 217-221, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33486691

RESUMO

Tick-borne encephalitis (TBE) has been a notifiable disease in Germany since 2001. Its causative agent, the TBE virus (TBEV), is the most important arbovirus in Europe and Northern Asia. The illness, caused by the European Subtype usually displays flu-like symptoms, but can result in sequelae and, in 2 % of all cases, in death. Over the last few decades, the virus has spread into new habitats, such as higher altitudes in the Alpine region. For this study, it was hypothesized that the environmental challenges that the virus might be exposed to at such altitudes could lead to the selection of viral strains with a higher resilience to such environmental factors. To determine whether strains identified at higher altitudes possessed different genetic traits compared to viruses from lower altitudes, an analysis of viral genomes from higher Alpine altitudes (> 500 m above sea level) (n = 5) and lower altitudes (< 500 m above sea level) (n = 4) was performed. No common phylogenetic ancestry or shared amino acid substitutions could be identified that differentiated the alpine from the lowland viral strains. These findings support the idea of many individual introductions of TBEV into the alpine region and the establishment of foci due to non-viral specific factors such as favorable conditions for vector species and host animals due to climate change.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Genoma Viral , Altitude , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Filogenia , Tundra
2.
J Clin Microbiol ; 58(4)2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-31969423

RESUMO

Tick-borne encephalitis virus (TBEV) is an important central nervous system (CNS) infection in Europe and Asia. It is a flavivirus in the tick-borne group. Effective vaccines against TBE are available in the affected countries. However, diagnosing TBE is challenging due to cross-reactive antibodies between different viruses of the genus Flavivirus, family Flaviviridae. Differentiation between infection-induced and vaccine-induced antibodies can be difficult and in many cases impossible, due to the increasing vaccination rate against TBEV. We present a new approach to detect antibodies against the TBEV nonstructural protein 1 (NS1) as a diagnostic marker, which is exclusively indicative for virus replication in natural infection, on the basis of an enzyme-linked immunosorbent assay (ELISA). A total of 188 anonymous serum samples from the National Consultant Laboratory for TBEV were included in our study. The assay was validated according to the European Laboratory Norm DIN EN ISO 15189 for diagnostic use. The ELISA for the detection of TBEV NS1 specific IgG class antibodies has demonstrated a sensitivity of >94% and a specificity of >93% in broadly cross-reacting sera from patients with vaccinations against flaviviral diseases and single or multiple flavivirus infections, respectively. The detection of anti-NS1 antibodies is feasible and facilitates reliable differentiation between different flavivirus infections, TBEV infection, and TBE vaccination.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Anticorpos Antivirais , Formação de Anticorpos , Ásia , Encefalite Transmitida por Carrapatos/diagnóstico , Encefalite Transmitida por Carrapatos/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Europa (Continente) , Humanos , Imunoglobulina G , Vacinação
3.
J Antimicrob Chemother ; 72(5): 1359-1363, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28108677

RESUMO

Objectives: As part of the multicentre Antibiotic Therapy Optimisation Study, MIC values of 19 non-ß-lactam agents were determined for third-generation cephalosporin-resistant Escherichia coli , Klebsiella species and Enterobacter species (3GCREB) isolates collected in German hospitals. Methods: A total of 328 E. coli , 35 Klebsiella spp. (1 Klebsiella oxytoca and 34 Klebsiella pneumoniae ) and 16 Enterobacter spp. (1 Enterobacter aerogenes and 15 Enterobacter cloacae ) isolates were submitted to broth microdilution antimicrobial susceptibility testing with the MICRONAUT system. MICs of fluoroquinolones (levofloxacin and moxifloxacin), aminoglycosides (gentamicin, tobramycin, amikacin, streptomycin, neomycin and paromomycin), tetracyclines (tetracycline, minocycline and tigecycline), macrolides (erythromycin, clarithromycin and azithromycin) and miscellaneous agents [trimethoprim/sulfamethoxazole, chloramphenicol, nitrofurantoin, colistin and fosfomycin intravenous (iv)] were determined and reviewed against 2016 EUCAST breakpoints. Results: The MIC of levofloxacin was >2 mg/L for 128 of 328 E. coli and 8 of 35 Klebsiella spp., but only 1 of 16 Enterobacter spp. Rates of resistance to trimethoprim/sulfamethoxazole were high (>70%), except for Enterobacter spp. Rates of resistance to colistin and fosfomycin iv were still low. About 20% of the tested isolates were resistant to chloramphenicol. Only 1 (of 328) E. coli isolate had an MIC of amikacin >16 mg/L and only 33 of 328 E. coli and 1 of 35 Klebsiella spp. had an MIC of tobramycin >4 mg/L, whereas average gentamicin MICs were in general more elevated. A tigecycline MIC >2 mg/L was only found for 1 of 16 Enterobacter spp., but in none of the E. coli or Klebsiella spp. isolates. Conclusions: Our study gives insight into previously unreported non-ß-lactam MIC distributions of 3GCREB isolates.


Assuntos
Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Farmacorresistência Bacteriana , Enterobacter/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Klebsiella/efeitos dos fármacos , Resistência às Cefalosporinas , Colistina/farmacologia , Enterobacter/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/isolamento & purificação , Hospitalização , Humanos , Klebsiella/isolamento & purificação , Testes de Sensibilidade Microbiana , Minociclina/análogos & derivados , Minociclina/farmacologia , Centros de Atenção Terciária , Tetraciclina/farmacologia , Tigeciclina , beta-Lactamases/metabolismo , beta-Lactamas/farmacologia
4.
J Antimicrob Chemother ; 71(10): 2957-63, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27317445

RESUMO

OBJECTIVES: The objectives of this study were to prospectively assess the rectal carriage rate of third-generation cephalosporin-resistant Enterobacteriaceae (3GCREB) in non-ICU patients on hospital admission and to investigate resistance mechanisms and risk factors for carriage. METHODS: Adult patients were screened for 3GCREB carriage at six German tertiary care hospitals in 2014 using rectal swabs or stool samples. 3GCREB isolates were characterized by phenotypic and molecular methods. Each patient answered a questionnaire about potential risk factors for colonization with MDR organisms (MDROs). Univariable and multivariable risk factor analyses were performed to identify factors associated with 3GCREB carriage. RESULTS: Of 4376 patients, 416 (9.5%) were 3GCREB carriers. Escherichia coli was the predominant species (79.1%). ESBLs of the CTX-M-1 group (67.3%) and the CTX-M-9 group (16.8%) were the most frequent ß-lactamases. Five patients (0.11%) were colonized with carbapenemase-producing Enterobacteriaceae. The following risk factors were significantly associated with 3GCREB colonization in the multivariable analysis (P < 0.05): centre; previous MDRO colonization (OR = 2.12); antibiotic use within the previous 6 months (OR = 2.09); travel outside Europe (OR = 2.24); stay in a long-term care facility (OR = 1.33); and treatment of gastroesophageal reflux disease (GERD) (OR = 1.22). CONCLUSIONS: To our knowledge, this is the largest admission prevalence study of 3GCREB in Europe. The observed prevalence of 9.5% 3GCREB carriage was higher than previously reported and differed significantly among centres. In addition to previously identified risk factors, the treatment of GERD proved to be an independent risk factor for 3GCREB colonization.


Assuntos
Portador Sadio/epidemiologia , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/isolamento & purificação , Reto/microbiologia , Adulto , Idoso , Antibacterianos/uso terapêutico , Portador Sadio/microbiologia , Cefalosporinas , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/microbiologia , Infecções por Escherichia coli/epidemiologia , Feminino , Alemanha/epidemiologia , Hospitalização , Humanos , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Prevalência , Estudos Prospectivos , Fatores de Risco
5.
Eur J Clin Microbiol Infect Dis ; 33(7): 1133-41, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24452967

RESUMO

Metallo-beta-lactamase (MBL) production in Pseudomonas aeruginosa is a growing issue across the globe. Fast and reliable diagnostic tools are needed for appropriate implementation of infection control measures. In this study we evaluated the performance of three commercial combined disk tests, two EDTA based in-house combined disk tests and the Carba NP test in comparison to molecular detection of MBL genes on 133 meropenem non-susceptible non-duplicate P. aeruginosa clinical isolates. The meropenem/DPA based commercial KPC + MBL-confirm ID kit (Rosco Diagnostica, Denmark) and the MASTDISCS™ ID carbapenemase (Enterobacteriaceae) detection disc set (MAST Diagnostics, UK) showed sensitivities of 31.1 % and 28.8 % and specificities of 69.3 % and 79.6 %, respectively. The total MBL confirm kit (Rosco Diagnostica, Denmark) contains imipenem/DPA and imipenem/EDTA combination disks. Evaluation of the single disk combinations revealed 84.4 % sensitivity and 81.8 % specificity for the imipenem/DPA assay and 86.7 % sensitivity and 51.1 % specificity for the imipenem/EDTA test. Applying both tests simultaneously resulted in a slightly higher sensitivity of 88.9 % but a lower specificity of 48.9 % when compared to the single tests alone. The Carba NP test showed 93.3 % sensitivity and 96.6 % specificity. All phenotypic combined disk tests lacked either sensitivity or specificity for the detection of MBL in P. aeruginosa. The Carba NP test showed excellent test properties, but suffers from drawbacks in handling and high costs. The optimal diagnostic approach needs to be chosen depending on the epidemiological situation, laboratory resources and availability of molecular confirmation tests.


Assuntos
Antibacterianos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/enzimologia , Resistência beta-Lactâmica , beta-Lactamases/análise , beta-Lactamas/farmacologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Sensibilidade e Especificidade
6.
Allergy ; 67(7): 858-68, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22583069

RESUMO

BACKGROUND: Advanced mast cell (MC) disorders are characterized by uncontrolled growth of neoplastic MC in various organs, mediator-related symptoms, and a poor prognosis. Kit mutations supposedly contribute to abnormal growth and drug resistance in these patients. METHODS: We established a novel canine mastocytoma cell line, NI-1, from a patient suffering from MC leukemia. RESULTS: NI-1 cells were found to form mastocytoma lesions in NOD/SCID IL-2Rgamma(null) mice and to harbor several homozygous Kit mutations, including missense mutations at nucleotides 107(C→T) and 1187(A→G), a 12-bp duplication (nucleotide 1263), and a 12-bp deletion (nucleotide 1550). NI-1 cells expressed several MC differentiation antigens, including tryptase, Kit, and a functional IgE receptor. Compared to the C2 mastocytoma cell line harboring a Kit exon 11 mutation, NI-1 cells were found to be less responsive against the Kit tyrosine kinase inhibitors (TKI) masitinib and imatinib, but were even more sensitive against proliferation-inhibitory effects of the mammalian target of rapamycin (mTOR) blocker RAD001 and PI3-kinase/mTOR blocker NVP-BEZ235. The Kit-targeting multikinase inhibitors PKC412 and dasatinib were also found to override TKI resistance in NI-1 cells, and produced growth inhibition with reasonable IC(50) values (<0.1 µM). CONCLUSION: NI-1 may serve as a useful tool to investigate IgE-dependent reactions and mechanisms of abnormal growth and drug resistance in neoplastic MC in advanced mastocytosis.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Mastócitos/patologia , Mastocitoma/imunologia , Mastocitoma/metabolismo , Receptores de IgE/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cães , Ativação Enzimática/efeitos dos fármacos , Liberação de Histamina , Imunofenotipagem , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Mastocitoma/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Fenótipo , Proteínas Proto-Oncogênicas c-kit/genética , Receptores de IgE/imunologia
7.
Eur J Clin Invest ; 39(5): 384-94, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19309323

RESUMO

BACKGROUND: Development of betulinic acid derivatives for clinical use has been hampered by adverse pharmacological and physico-chemical characteristics of this class of compounds. We here present a novel semi-synthetic betulinic acid-derived drug candidate well suited for further clinical development. MATERIALS AND METHODS: In vitro activity and mode of action of NVX-207 were determined using normal as well as cancer cell lines. Gene expression profiling was performed with Affymetrix U133 microarrays. NVX-207 binding partners were identified using a heterobifunctional chemical crosslinker system. Potential binding proteins were identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) analysis. Clinical studies were conducted in canine cancer patients suffering from spontaneously arising pre-treated tumours. RESULTS: NVX-207 showed anti-tumour activity (mean IC(50) = 3.5 microM) against various human and canine cell lines. NVX-207-induced apoptosis was associated with activation of the intrinsic apoptotic pathway via cleavage of caspases -9, -3, -7 and of poly (ADP-ribose) polymerase (PARP). Global gene expression profiling demonstrated regulation of genes associated with lipid metabolism, most notably an upregulation of genes coding for insulin-induced gene 1 (Insig-1), low-density lipoprotein receptor (LDL-R) and of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA). NVX-207 bound to apolipoprotein A-I, a major regulator of lipid metabolism and cholesterol transport. A phase I/II study in dogs suffering from naturally occurring cancer receiving local treatment of NVX-207 (10 mg mL(-1)) showed excellent clinical responses including a complete remission in so far 5/5 treated animals. CONCLUSIONS: NVX-207 is well tolerated and has significant anti-cancer activity in vitro and in vivo in dogs with treatment-resistant malignancies.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Propanolaminas/farmacologia , Triterpenos/farmacologia , Animais , Linhagem Celular Tumoral/efeitos dos fármacos , Cães , Feminino , Humanos , Camundongos , Modelos Animais , Triterpenos Pentacíclicos , Ácido Betulínico
8.
Vet Immunol Immunopathol ; 128(4): 359-65, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19100628

RESUMO

The Pax5 gene encodes the B-cell specific activator protein (BSAP), a member of the highly conserved paired box (PAX)-domain family of transcription factors and a key regulator in the development and differentiation of B-cells. Pax5 serves as a valuable B-cell marker in the classification of human lymphoma patients as it is restricted to lymphomas of B-cell lineage. In dogs, detection of Pax5 protein in lymphoma tissue has not been reported. Therefore, we have investigated the expression and detection of BSAP using a monoclonal anti-Pax5 antibody (anti-BSAP, clone 24) in canine lymphoma tissue samples to evaluate its diagnostic relevance as a B-cell marker. A series of 25 lymph nodes from 23 canine non-Hodgkin lymphoma patients, a reactive canine lymph node, and a normal non-reactive canine lymph node, were evaluated. All B-cell non-Hodgkin lymphomas (15) were found to express Pax5 protein. In addition, there was a strong correlation between Pax5 and CD79a expression. Three CD3 positive and five CD3 and CD79a positive lymphomas were immunophenotypically negative for anti-Pax5, indicating a T-cell lineage. In conclusion, anti-Pax5 antibody may offer an excellent B-cell marker in canine lymphomas.


Assuntos
Linfócitos B/imunologia , Doenças do Cão/imunologia , Linfoma não Hodgkin/veterinária , Fator de Transcrição PAX5/biossíntese , Animais , Linfócitos B/patologia , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Cães , Feminino , Imuno-Histoquímica/veterinária , Imunofenotipagem/veterinária , Linfonodos/imunologia , Linfonodos/patologia , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/patologia , Masculino , Fator de Transcrição PAX5/análise , Fator de Transcrição PAX5/imunologia , Inclusão em Parafina/veterinária
9.
Comput Biol Chem ; 74: 420-427, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29567068

RESUMO

Bacterial viruses contribute to the dynamics of the microbiome communities, as they are involved in the horizontal gene transfer. Previously we studied changes in the gut microbiome of the two healthy individuals over the course of a 6-days antibiotics treatment and subsequent 28 days recovery time (Willmann et al., 2015). Now, from the same samples, the virus-like particles were isolated and sequenced. As the phage sequences are currently poorly represented in reference databases, the reads had to be assembled, annotated and their abundance had to be evaluated via reads mapping. We analyzed and compared patterns of changes in abundance of the phage scaffolds and scaffolds with antibiotics resistant genes, in both phage and whole-genome metagenomic sets. We observed an increase in abundance of scaffolds carrying antibiotic-resistant genes in response to the treatment.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Antibacterianos/administração & dosagem , Ciprofloxacina/administração & dosagem , Microbioma Gastrointestinal/genética , Trato Gastrointestinal/microbiologia , Voluntários Saudáveis , Humanos , Metagenômica
10.
Int J Antimicrob Agents ; 51(6): 867-874, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29412174

RESUMO

Citrobacter spp. harbouring metallo-ß-lactamases (MBLs) have been reported from various countries and different sources, but their isolation from clinical specimens remains a rare event in Europe. MBL-harbouring Enterobacteriaceae are considered a major threat in infection control as therapeutic options are often limited to colistin. In this study, whole-genome sequencing was applied to characterise five clinical isolates of multidrug-resistant Citrobacter werkmanii obtained from rectal swabs. Four strains possessed a class 1 integron with a novel blaVIM-48 MBL resistance gene and the aminoglycoside acetyltransferase gene aacA4, whilst one isolate harboured a blaIMP-8 MBL. Resistance to colistin evolved in one strain isolated from a patient who had received colistin orally for 8 days. Genomic comparison of this strain with a colistin-susceptible pre-treatment isolate from the same patient revealed 66 single nucleotide polymorphisms (SNPs) and 26 indels, indicating the presence of a mutator phenotype. This was confirmed by the finding of a SNP in the mutL gene that led to a significantly truncated protein. Additionally, an amino acid change from glycine to serine at position 53 was observed in PmrA. Mutations in the pmrA gene have been previously described as mediating colistin resistance in different bacterial species and are the most likely reason for the susceptibility change observed. To the best of our knowledge, this is the first description of a colistin-resistant Citrobacter spp. isolated from a human sample. This study demonstrates the power of applying next-generation sequencing in a hospital setting to trace and understand evolving resistance at the level of individual patients.


Assuntos
Antibacterianos/farmacologia , Citrobacter/efeitos dos fármacos , Citrobacter/genética , Colistina/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Genoma Bacteriano/genética , Proteínas de Bactérias/genética , Citrobacter/classificação , Citrobacter/isolamento & purificação , Humanos , Mutação INDEL/genética , Metiltransferases/genética , Testes de Sensibilidade Microbiana , Proteínas MutL/genética , Polimorfismo de Nucleotídeo Único/genética , Sequenciamento Completo do Genoma , beta-Lactamases/genética
11.
Leukemia ; 32(4): 1016-1022, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29249817

RESUMO

Systemic mastocytosis (SM) is a mast cell (MC) neoplasm with complex pathology and a variable clinical course. In aggressive SM (ASM) and MC leukemia (MCL), responses to conventional drugs are poor and the prognosis is dismal. R763 is a multi-kinase inhibitor that blocks the activity of Aurora-kinase-A/B, ABL1, AKT and FLT3. We examined the effects of R763 on proliferation and survival of neoplastic MC. R763 produced dose-dependent inhibition of proliferation in the human MC lines HMC-1.1 (IC50 5-50 nM), HMC-1.2 (IC50 1-10 nM), ROSAKIT WT (IC50 1-10 nM), ROSAKIT D816V (IC50 50-500 nM) and MCPV-1.1 (IC50 100-1000 nM). Moreover, R763 induced growth inhibition in primary neoplastic MC in patients with ASM and MCL. Growth-inhibitory effects of R763 were accompanied by signs of apoptosis and a G2/M cell cycle arrest. R763 also inhibited phosphorylation of KIT, BTK, AKT and STAT5 in neoplastic MC. The most sensitive target appeared to be STAT5. In fact, tyrosine phosphorylation of STAT5 was inhibited by R763 at 10 nM. At this low concentration, R763 produced synergistic growth-inhibitory effects on neoplastic MC when combined with midostaurin or dasatinib. Together, R763 is a novel promising multi-kinase inhibitor that blocks STAT5 activation and thereby overrides drug-resistance in neoplastic MC.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT5/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dasatinibe/farmacologia , Cães , Sinergismo Farmacológico , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Leucemia de Mastócitos/tratamento farmacológico , Leucemia de Mastócitos/metabolismo , Masculino , Mastócitos/metabolismo , Mastocitose Sistêmica/tratamento farmacológico , Mastocitose Sistêmica/metabolismo , Pessoa de Meia-Idade , Norbornanos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Pirimidinas/farmacologia , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia , Adulto Jovem
12.
J Comp Pathol ; 137(1): 30-40, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17467003

RESUMO

Vascular endothelial growth factor (VEGF) stimulates endothelial cell proliferation and has a pivotal role in tumour angiogenesis. The expression of VEGF and its receptors VEGFR-1 and VEGFR-2 was examined immunohistochemically in 43 specimens of canine lymphoma and in six normal lymph nodes. Western blotting and reverse transcriptase polymerase chain reaction (RT-PCR) were performed to detect VEGF protein and mRNA, respectively. VEGF protein was expressed by 60% of the tumours with diffuse cytoplasmic labelling of the neoplastic cells. Endothelial cells, macrophages and plasma cells were also immunolabelled. VEGFR-1 was expressed by variable numbers of neoplastic cells in 54% of lymphoma specimens. VEGFR-1 was also expressed by macrophages, plasma cells, reticulum cells, and vascular endothelial cells. Macrophages and lymphocytes in germinal centres of normal lymph nodes were also immunoreactive with anti-VEGF and VEGFR-1. Most tumours did not express VEGFR-2 but in 7% of sections there was focal labelling of neoplastic and endothelial cells, with a cytoplasmic and perinuclear pattern. The observed variability in expression of VEGF and its receptors probably relates to the fact that lymphoma is a heterogeneous lymphoproliferative tumour. Individual differences in VEGF and VEGFR expression must be taken into account when VEGF and VEGFR-targeted approaches for anti-angiogenic therapy are considered in dogs.


Assuntos
Doenças do Cão/metabolismo , Linfoma de Células B/veterinária , Linfoma de Células T/veterinária , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Doenças do Cão/patologia , Cães , Regulação Neoplásica da Expressão Gênica , Linfonodos/metabolismo , Linfonodos/patologia , Linfoma de Células B/metabolismo , Linfoma de Células T/metabolismo , RNA Mensageiro/metabolismo
13.
Vet Comp Oncol ; 15(4): 1240-1256, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27507155

RESUMO

CD30 is a novel therapeutic target in human mast cell (MC) neoplasms. In this 'comparative oncology' study, we examined CD30 expression and regulation in neoplastic canine MC using a panel of immunomodulatory cytokines [interleukin-2 (IL-2), IL-4, IL-5, IL-6, IL-13 and stem cell factor (SCF)] and the canine mastocytoma cell lines NI-1 and C2. Of all cytokines tested IL-4 was found to downregulate expression of CD30 in NI-1 and C2 cells. We also found that the CD30-targeting antibody-conjugate brentuximab vedotin induces growth inhibition and apoptosis in both MC lines. Next, we asked whether IL-4-induced downregulation of CD30 interferes with brentuximab vedotin-effects. Indeed, pre-incubation of NI-1 cells with IL-4 decreased responsiveness towards brentuximab vedotin. To overcome IL-4-mediated resistance, we applied drug combinations and found that brentuximab vedotin synergizes with the Kit-targeting drugs masitinib and PKC412 in inhibiting growth of NI-1 and C2 cells. In summary, CD30 is a new marker and IL-4-regulated target in neoplastic canine MC.


Assuntos
Doenças do Cão/metabolismo , Interleucina-4/fisiologia , Antígeno Ki-1/metabolismo , Mastocitose/veterinária , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzamidas , Brentuximab Vedotin , Linhagem Celular Tumoral , Citocinas/metabolismo , Cães , Regulação para Baixo , Sinergismo Farmacológico , Feminino , Imunoconjugados/farmacologia , Masculino , Mastocitose/metabolismo , Piperidinas , Piridinas , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia , Tiazóis/farmacologia
14.
J Contam Hydrol ; 82(1-2): 23-43, 2006 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-16216383

RESUMO

We address advective transport of a solute traveling toward a single pumping well in a two-dimensional randomly heterogeneous aquifer. The two random variables of interest are the trajectory followed by an individual particle from the injection point to the well location and the particle travel time under steady-state conditions. Our main objective is to derive the predictors of trajectory and travel time and the associated uncertainty, in terms of their first two statistical moments (mean and variance). We consider a solute that undergoes mass transfer between a mobile and an immobile zone. Based on Lawrence et al. [Lawrence, A.E., Sánchez-Vila, X., Rubin, Y., 2002. Conditional moments of the breakthrough curves of kinetically sorbing solute in heterogeneous porous media using multirate mass transfer models for sorption and desorption. Water Resour. Res. 38 (11), 1248, doi:10.1029/2001WR001006.], travel time moments can be written in terms of those of a conservative solute times a deterministic quantity. Moreover, the moments of solute particles trajectory do not depend on mass transfer processes. The resulting mean and variance of travel time and trajectory for a conservative species can be written as functions of the first, second moments and cross-moments of trajectory and velocity components. The equations are developed from a consistent second order expansion in sigmaY (standard deviation of the natural logarithm of hydraulic conductivity). Our solution can be completely integrated with the moment equations of groundwater flow of Guadagnini and Neuman [Guadagnini, A., Neuman, S.P., 1999a. Nonlocal and localized analyses of conditional mean steady state flow in bounded, randomly non uniform domains 1. Theory and computational approach. Water Resour. Res. 35(10), 2999-3018.,Guadagnini, A., Neuman, S.P., 1999b. Nonlocal and localized analyses of conditional mean steady state flow in bounded, randomly non uniform domains 2. Computational examples. Water Resour. Res. 35(10), 3019-3039.], it is free of distributional assumptions regarding the log conductivity field, and formally includes conditioning. We present analytical expressions for the unconditional case by making use of the results of Riva et al. [Riva, M., Guadagnini, A., Neuman, S.P., Franzetti, S., 2001. Radial flow in a bounded randomly heterogeneous aquifer. Transport in Porous Media 45, 139-193.]. The quality of the solution is supported by numerical Monte Carlo simulations. Potential uses of this work include the determination of aquifer reclamation time by means of a single pumping well, and the demarcation of the region potentially affected by the presence of a contaminant in the proximity of a well, whenever the aquifer is very thin and Dupuit-Forchheimer assumption holds.


Assuntos
Modelos Teóricos , Análise Numérica Assistida por Computador , Poluentes do Solo/análise , Poluentes da Água/análise , Abastecimento de Água , Cinética , Tamanho da Partícula , Porosidade , Reologia , Esporos , Movimentos da Água
15.
Artigo em Inglês | MEDLINE | ID: mdl-26274277

RESUMO

Intermittency of Lagrangian velocity and acceleration is a key to understanding transport in complex systems ranging from fluid turbulence to flow in porous media. High-resolution optical particle tracking in a three-dimensional (3D) porous medium provides detailed 3D information on Lagrangian velocities and accelerations. We find sharp transitions close to pore throats, and low flow variability in the pore bodies, which gives rise to stretched exponential Lagrangian velocity and acceleration distributions characterized by a sharp peak at low velocity, superlinear evolution of particle dispersion, and double-peak behavior in the propagators. The velocity distribution is quantified in terms of pore geometry and flow connectivity, which forms the basis for a continuous-time random-walk model that sheds light on the observed Lagrangian flow and transport behaviors.


Assuntos
Modelos Teóricos , Porosidade , 2-Propanol , Polímeros de Fluorcarboneto , Hidrodinâmica , Tomografia Computadorizada por Raios X , Água
16.
Nucl Med Biol ; 28(1): 75-84, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11182567

RESUMO

The potential utility of neurotensin (NT) in cancer diagnosis and therapy is limited by its rapid degradation. New stabilized analogues were synthesized, labeled with [99mTc] and screened in vitro and in vivo. High affinity and rapid internalization were obtained in binding assays. Despite their longer human plasma half-lives, a rapid degradation was observed with low concentrations as used in biodistribution tests. The tumor uptake rates were rather low but tumor/blood ratios increased according to the stability raise.


Assuntos
Neurotensina/análogos & derivados , Neurotensina/farmacocinética , Fragmentos de Peptídeos/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Receptores de Neurotensina/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Células HT29/metabolismo , Meia-Vida , Humanos , Camundongos , Camundongos Nus , Neurotensina/síntese química , Neurotensina/metabolismo , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/metabolismo , Relação Estrutura-Atividade , Distribuição Tecidual
17.
Phytopathology ; 90(9): 987-94, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18944524

RESUMO

ABSTRACT Phytophthora infestans is generally regarded as heterothallic-requiring physical proximity of two individuals of different mating type (A1 and A2) for oosporogenesis. Recent reports of limited selfing in young cultures of this oomycete stimulated us to investigate factors contributing to the phenomenon. The ability to produce oospores rapidly (within 2 weeks) in pure, single individual cultures (self-fertility) was tested in 116 individual isolates. The 116 isolates were from geographically diverse locations (16 countries) and were genetically diverse. Mating type and growth medium were the most prominent factors in determining if an isolate would be self-fertile. The majority of A2 isolates (45 of 47 tested) produced oospores when grown on a 50:50 mixture of V8 and rye B medium. In contrast, the majority of A1 isolates (65 of 69 tested) did not produce oospores on this medium. None of the 116 isolates produced oospores when grown on rye B medium (with no V8 juice). Further tests on representative A1 and A2 isolates revealed that oatmeal agar, tomato juice agar, and V8-juice agar all induced the A2 mating type isolate to produce oospores but did not induce the A1 mating type isolate to produce oospores. Calcium carbonate and pH did not alter the self-fertile oospore production in either A1 or A2 mating type isolates. For in vivo tests, the application of fungicide to potato or tomato leaf tissue either before or after inoculation did not stimulate any individual isolate (one A2 and one A1 isolate) to produce oospores in infected tissue. However, in all of the controls for all experiments (in vivo and in vitro), many oospores were produced rapidly if both strains grew in physical proximity.

18.
Schweiz Arch Tierheilkd ; 145(10): 482-5, 2003 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-14593934

RESUMO

An 8 year old, intact female, Old English Sheepdog was presented with lethargy and chronic weight loss of one year duration. The dog suffered from recurrent fever and a mild peripheral lymphadenopathy. Mild thrombocytopenia, monoclonal hyperglobulinemia and positive Ehrlichia canis antibody titer were indicative of Ehrlichiosis. The patient developed proteinuria and renal failure, which suggested the presence of glomerulopathy. Immunohistochemical staining of renal biopsy specimen demonstrated AA amyloidosis. Chronic ehrlichiosis was suspected to be the cause of the dog's renal amyloidosis.


Assuntos
Amiloidose/veterinária , Doenças do Cão/diagnóstico , Ehrlichia canis , Ehrlichiose/veterinária , Nefropatias/veterinária , Amiloidose/microbiologia , Amiloidose/patologia , Animais , Anticorpos Antibacterianos/sangue , Doença Crônica , Doenças do Cão/microbiologia , Doenças do Cão/patologia , Cães , Ehrlichia canis/imunologia , Ehrlichia canis/isolamento & purificação , Ehrlichiose/complicações , Ehrlichiose/diagnóstico , Evolução Fatal , Feminino , Imuno-Histoquímica/veterinária , Nefropatias/microbiologia , Nefropatias/patologia
19.
New Microbes New Infect ; 2(2): 42-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25356340

RESUMO

Metallo-ß-lactamases (MBLs) in Enterobacteriaceae are an increasing problem worldwide. This report describes the isolation of Citrobacter freundii carrying IMP-8 MBL from three patients during the period from March 2012 until March 2013 in Germany. The bla IMP-8 enzyme is predominantly found in Asia, where IMP-8 has spread to various enterobacterial species causing serious infections. To our best knowledge, this is the first report of bla IMP-8 habouring Enterobacteriaceae in Europe.

20.
J Small Anim Pract ; 54(1): 20-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23190121

RESUMO

OBJECTIVE: To determine the clinical efficacy and safety of a cremophor-free formulation of paclitaxel (Paccal Vet, Oasmia Pharmaceuticals) in dogs with mast cell tumours. METHODS: Paccal Vet was administered at a median dose of 145 (range, 135 to 150) mg/m(2) intravenously once every 21 days for three cycles to 29 dogs with macroscopic grade 2 or 3 mast cell tumour. Efficacy was assessed by tumour response (Response Evaluation Criteria in Solid Tumours version 1.0) and performance status score. Progression-free survival, quality of life and safety/adverse events were also evaluated. Clinical safety was assessed by clinicopathological analyses and recording of adverse events. RESULTS: Complete or partial response was observed in 59% of dogs. Performance status score remained constant or improved for 20 dogs and decreased by one grade for 9 dogs. Median time to progression was 247 (range, 42 to 268) days. Expected, transient frequently subclinical adverse events (primarily grade 3/4 neutropenia and grade 1/2 leukopenia) were observed in the majority of dogs. Nine dogs were euthanased and one dog died due to disease progression. CLINICAL SIGNIFICANCE: Paccal Vet appears to be a clinically safe and effective treatment for canine mast cell tumours. Further controlled confirmatory investigation is warranted.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Mastocitoma/veterinária , Paclitaxel/uso terapêutico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/efeitos adversos , Intervalo Livre de Doença , Doenças do Cão/psicologia , Cães , Feminino , Infusões Intravenosas/veterinária , Masculino , Mastocitoma/tratamento farmacológico , Mastocitoma/psicologia , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Estudos Prospectivos , Qualidade de Vida , Suécia , Resultado do Tratamento
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