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1.
Front Public Health ; 12: 1415778, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38979040

RESUMO

Non-pharmaceutical interventions (NPI) have been proven successful in a population-based approach to protect from SARS-CoV-2 transmission during the COVID-19 pandemic. As a consequential-effect, a reduction in the spread of all respiratory viruses has been observed, but the primary factors behind this phenomenon have yet to be identified. We conducted a subgroup analysis of participants from the ELISA study, a prospective longitudinal cohort study on SARS-CoV-2 transmission, at four timepoints from November 2020 - September 2022. The aim was to provide a detailed overview of the circulation of respiratory viruses over 2 years and to identify potential personal risk factors of virus distribution. All participants were screened using qPCR for respiratory viral infections from nasopharyngeal swabs and answered a questionnaire regarding behavioral factors. Several categories of risk factors for the transmission of respiratory viruses were evaluated using a scoring system. In total, 1,124 participants were included in the study, showing high adherence to governmental-introduced NPI. The overall number of respiratory virus infections was low (0-4.9% of participants), with adenovirus (1.7%), rhino-/enterovirus (3.2%) and SARS-CoV-2 (1.2%) being the most abundant. We detected an inverse correlation between the number and intensity of NPI and the number of detected respiratory viruses. More precisely, the attendance of social events and household size was associated with rhino-/enterovirus infection while social contacts were associated with being positive for any virus. NPI introduced during the COVID-19 pandemic reduced the occurrence of seasonal respiratory viruses in our study, showing different risk-factors for enhanced transmission between viruses. Trial registration: DRKS.de, German Clinical Trials Register (DRKS), Identifier: DRKS00023418, Registered on 28 October 2020.


Assuntos
COVID-19 , Infecções Respiratórias , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/transmissão , Estudos Prospectivos , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/prevenção & controle , Infecções Respiratórias/virologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Longitudinais , Fatores de Risco , Idoso , Distanciamento Físico , Adolescente , Adulto Jovem , Alemanha/epidemiologia
2.
Liver Int ; 43(4): 785-793, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36621849

RESUMO

BACKGROUND AND AIMS: Screening strategies for undiagnosed infections are fundamental for hepatitis C virus (HCV) elimination. We previously investigated HCV prevalence and screening strategies in an urban primary care setting. IV drug abuse, blood transfusion before 1992, immigration, or elevated ALT were identified as risk factors in a post hoc analysis and diagnosed 83% of unknown HCV-RNA-positive cases by screening only 26% of the population. We aimed to validate prospectively the proposed screening algorithm in two independent urban and rural cohorts and to analyse for potential differences. METHODS: Anti-HCV and ALT were included in a routine check-up together with a questionnaire covering risk factors. HCV-RNA was analysed in anti-HCV-positive individuals. RESULTS: In urban and rural areas, 4323 and 9321 individuals were recruited. The anti-HCV prevalence was 0.56% and 0.49%, and 0.1% of patients were HCV-RNA-positive in both regions. Fifty-two anti-HCV positive patients including eight HCV-RNA-positive cases were unaware of the infection (number needed to screen to detect one unknown anti-HCV-positive individual: 262). At least one of the three aforementioned risk factors or elevated serum ALT was present in 3000 patients (22%). Restricting HCV screening to only those with risk factors, 52% and 75% of all anti-HCV and HCV-RNA-positive undiagnosed patients were identified (number needed to screen: 111). CONCLUSIONS: We confirm prospectively the efficiency of a risk-based HCV screening. The risk-based algorithm should be evaluated in other countries with similarly low HCV prevalence as in Germany to achieve WHO HCV elimination goals.


Assuntos
Anticorpos Anti-Hepatite C , Hepatite C , Humanos , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Hepacivirus/genética , Programas de Rastreamento , RNA Viral , Prevalência , Atenção Primária à Saúde
3.
Noncoding RNA ; 9(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36649031

RESUMO

Traditionally, small molecule-based drug discovery has mainly focused on proteins as the drug target. Opening RNA as an additional target space for small molecules offers the possibility to therapeutically modulate disease-driving non-coding RNA targets as well as mRNA of otherwise undruggable protein targets. MALAT1 is a highly conserved long-noncoding RNA whose overexpression correlates with poor overall patient survival in some cancers. We report here a fluorescence in-situ hybridization-based high-content imaging screen to identify small molecules that modulate the oncogenic lncRNA MALAT1 in a cellular setting. From a library of FDA approved drugs and known bioactive molecules, we identified two compounds, including Niclosamide, an FDA-approved drug, that lead to a rapid decrease of MALAT1 nuclear levels with good potency. Mode-of-action studies suggest a novel cellular regulatory pathway that impacts MALAT1 lncRNA nuclear levels by GSK3B activation and the involvement of the RNA modulating family of heterogenous nuclear ribonucleoproteins (hnRNPs). This study is the basis for the identification of novel targets that lead to a reduction of the oncogenic lncRNA MALAT1 in a cancer setting.

4.
Clin Chem ; 68(5): 646-656, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35157041

RESUMO

BACKGROUND: Differential leukocyte counts are usually measured based on cellular morphology or surface marker expression. It has recently been shown that leukocyte counts can also be determined by cell-type-specific DNA methylation (DNAm). Such epigenetic leukocyte counting is applicable to small blood volumes and even frozen material, but for clinical translation, the method needs to be further refined and validated. METHODS: We further optimized and validated targeted DNAm assays for leukocyte deconvolution using 332 venous and 122 capillary blood samples from healthy donors. In addition, we tested 36 samples from ring trials and venous blood from 266 patients diagnosed with different hematological diseases. Deconvolution of cell types was determined with various models using DNAm values obtained by pyrosequencing or digital droplet PCR (ddPCR). RESULTS: Relative leukocyte quantification correlated with conventional blood counts for granulocytes, lymphocytes, B cells, T cells (CD4 or CD8), natural killer cells, and monocytes with pyrosequencing (r = 0.84; r = 0.82; r = 0.58; r = 0.50; r = 0.70; r = 0.61; and r = 0.59, respectively) and ddPCR measurements (r = 0.65; r = 0.79; r = 0.56; r = 0.57; r = 0.75; r = 0.49; and r = 0.46, respectively). In some patients, particularly with hematopoietic malignancies, we observed outliers in epigenetic leukocyte counts, which could be discerned if relative proportions of leukocyte subsets did not sum up to 100%. Furthermore, absolute quantification was obtained by spiking blood samples with a reference plasmid of known copy number. CONCLUSIONS: Targeted DNAm analysis by pyrosequencing or ddPCR is a valid alternative to quantify leukocyte subsets, but some assays require further optimization.


Assuntos
Metilação de DNA , Epigenômica , Granulócitos , Humanos , Contagem de Leucócitos , Leucócitos
5.
J Med Chem ; 64(23): 17259-17276, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34818007

RESUMO

Polypharmaceutical regimens often impair treatment of patients with metabolic syndrome (MetS), a complex disease cluster, including obesity, hypertension, heart disease, and type II diabetes. Simultaneous targeting of soluble epoxide hydrolase (sEH) and peroxisome proliferator-activated receptor γ (PPARγ) synergistically counteracted MetS in various in vivo models, and dual sEH inhibitors/PPARγ agonists hold great potential to reduce the problems associated with polypharmacy in the context of MetS. However, full activation of PPARγ leads to fluid retention associated with edema and weight gain, while partial PPARγ agonists do not have these drawbacks. In this study, we designed a dual partial PPARγ agonist/sEH inhibitor using a structure-guided approach. Exhaustive structure-activity relationship studies lead to the successful optimization of the designed lead. Crystal structures of one representative compound with both targets revealed potential points for optimization. The optimized compounds exhibited favorable metabolic stability, toxicity, selectivity, and desirable activity in adipocytes and macrophages.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Epóxido Hidrolases/antagonistas & inibidores , PPAR gama/agonistas , Animais , Cristalografia por Raios X , Células HEK293 , Humanos , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Polimedicação , Ratos , Relação Estrutura-Atividade
6.
ChemMedChem ; 16(15): 2366-2374, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-33856122

RESUMO

Designed polypharmacology presents as an attractive strategy to increase therapeutic efficacy in multi-factorial diseases by a directed modulation of multiple involved targets with a single molecule. Such an approach appears particularly suitable in non-alcoholic steatohepatitis (NASH) which involves hepatic steatosis, inflammation and fibrosis as pathological hallmarks. Among various potential pharmacodynamic mechanisms, activation of the farnesoid X receptor (FXRa) and inhibition of leukotriene A4 hydrolase (LTA4Hi) hold promise to counteract NASH according to preclinical and clinical observations. We have developed dual FXR/LTA4H modulators as pharmacological tools, enabling evaluation of this polypharmacology concept to treat NASH and related pathologies. The optimized FXRa/LTA4Hi exhibits well-balanced dual activity on the intended targets with sub-micromolar potency and is highly selective over related nuclear receptors and enzymes rendering it suitable as tool to probe synergies of dual FXR/LTA4H targeting.


Assuntos
Ácido Quenodesoxicólico/análogos & derivados , Desenvolvimento de Medicamentos , Inibidores Enzimáticos/farmacologia , Epóxido Hidrolases/antagonistas & inibidores , Isoxazóis/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Ácido Quenodesoxicólico/síntese química , Ácido Quenodesoxicólico/química , Ácido Quenodesoxicólico/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Epóxido Hidrolases/metabolismo , Humanos , Isoxazóis/síntese química , Isoxazóis/química , Estrutura Molecular , Receptores Citoplasmáticos e Nucleares/metabolismo
7.
J Med Chem ; 64(5): 2815-2828, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33620196

RESUMO

The metabolic syndrome (MetS) is a constellation of cardiovascular and metabolic symptoms involving insulin resistance, steatohepatitis, obesity, hypertension, and heart disease, and patients suffering from MetS often require polypharmaceutical treatment. PPARγ agonists are highly effective oral antidiabetics with great potential in MetS, which promote adipocyte browning and insulin sensitization. However, the application of PPARγ agonists in clinics is restricted by potential cardiovascular adverse events. We have previously demonstrated that the racemic dual sEH/PPARγ modulator RB394 (3) simultaneously improves all risk factors of MetS in vivo. In this study, we identify and characterize the eutomer of 3. We provide structural rationale for molecular recognition of the eutomer. Furthermore, we could show that the dual sEH/PPARγ modulator is able to promote adipocyte browning and simultaneously exhibits cardioprotective activity which underlines its exciting potential in treatment of MetS.


Assuntos
Adipócitos/efeitos dos fármacos , Benzamidas/farmacologia , Butiratos/farmacologia , Cardiotônicos/farmacologia , Epóxido Hidrolases/metabolismo , PPAR gama/agonistas , Animais , Benzamidas/síntese química , Butiratos/síntese química , Cardiotônicos/síntese química , Diferenciação Celular/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Estereoisomerismo
8.
ChemMedChem ; 16(7): 1088-1092, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33283450

RESUMO

Designed multitarget ligands are a popular approach to generating efficient and safe drugs, and fragment-based strategies have been postulated as a versatile avenue to discover multitarget ligand leads. To systematically probe the potential of fragment-based multiple ligand discovery, we have employed a large fragment library for comprehensive screening on five targets chosen from proteins for which multitarget ligands have been successfully developed previously (soluble epoxide hydrolase, leukotriene A4 hydrolase, 5-lipoxygenase, retinoid X receptor, farnesoid X receptor). Differential scanning fluorimetry served as primary screening method before fragments hitting at least two targets were validated in orthogonal assays. Thereby, we obtained valuable fragment leads with dual-target engagement for six out of ten target combinations. Our results demonstrate the applicability of fragment-based approaches to identify starting points for polypharmacological compound development with certain limitations.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Araquidonato 5-Lipoxigenase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Epóxido Hidrolases/antagonistas & inibidores , Epóxido Hidrolases/metabolismo , Humanos , Estrutura Molecular , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores X de Retinoides/antagonistas & inibidores , Receptores X de Retinoides/metabolismo , Relação Estrutura-Atividade
10.
Sci Rep ; 8(1): 6846, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29717168

RESUMO

The bile acid activated transcription factor farnesoid X receptor (FXR) regulates numerous metabolic processes and is a rising target for the treatment of hepatic and metabolic disorders. FXR agonists have revealed efficacy in treating non-alcoholic steatohepatitis (NASH), diabetes and dyslipidemia. Here we characterize imatinib as first-in-class allosteric FXR modulator and report the development of an optimized descendant that markedly promotes agonist induced FXR activation in a reporter gene assay and FXR target gene expression in HepG2 cells. Differential effects of imatinib on agonist-induced bile salt export protein and small heterodimer partner expression suggest that allosteric FXR modulation could open a new avenue to gene-selective FXR modulators.


Assuntos
Mesilato de Imatinib/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Regulação Alostérica , Ácidos e Sais Biliares/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Mesilato de Imatinib/análogos & derivados , Mesilato de Imatinib/química , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/química , Fatores de Transcrição/análise , Fatores de Transcrição/metabolismo
11.
Anal Biochem ; 547: 7-13, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29410016

RESUMO

The protein arginine N-methyltransferase 6 (PRMT6) is overexpressed in a variety of different cancer types and plays a role in human immunodeficiency virus (HIV) infections. Furthermore, the PRMT6 activity might also influence the pathogenesis of neurodegenerative, inflammatory, and cardiovascular diseases, whereby it becomes an interesting target for drug development. Previously reported activity assays for PRMT6 activity are either expensive, time-consuming or use radioactive substrates. To overcome these challenges, we developed a coupled fluorescence-based activity assay using recombinant PRMT6 expressed in E. coli. In the first step of the assay, the fluorogenic substrate Nα-Benzoyl-L-arginine-7-amido-4-methylcoumarin (Bz-Arg-AMC) is methylated by PRMT6, while in a second step the remaining un-methylated substrate is cleaved by trypsin, producing the fluorescent 7-amino-4-methylcoumarin.


Assuntos
Proteínas Nucleares/análise , Peptídeos/química , Proteína-Arginina N-Metiltransferases/análise , Fluorescência , Humanos , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteína-Arginina N-Metiltransferases/química , Proteína-Arginina N-Metiltransferases/genética , Proteínas Recombinantes/análise , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
12.
Eur J Gastroenterol Hepatol ; 30(3): 280-283, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29324587

RESUMO

BACKGROUND: Identification of previously unknown cases is important to lower the burden of chronic hepatitis B and C infection. However, a screening program in the primary care setting has not yet been established. Therefore, a systematic screening project was conducted in 21 008 patients (Wolffram and colleagues). Here, we describe linkage to care of identified HbsAg-positive and anti-hepatitis C virus (HCV)-positive patients. METHODS: General practitioners characterized further medical care by a standardized questionnaire. Data of 48/110 HbsAg-positive and 114/199 anti-HCV-positive patients were available. An APRI index more than 2 or up to 0.5 indicated the presence of cirrhosis or the absence of fibrosis. RESULTS: APRI was calculated in 32/48 hepatitis B virus (HBV) patients (>2: n=1; ≤0.5: n=29) and 34/114 HCV patients (>2: n=4; ≤0.5: n=23). The general practitioners were already aware of the positive HBsAg and anti-HCV-test in 13/48 and 59/114 patients, respectively.For 29/35 newly diagnosed HBV patients and 26/55 HCV patients, further diagnostics were initiated: ultrasound 77 versus 38%, liver biopsy 20 versus 4%, and gastroscopy 20 versus 7%.Antiviral treatment was initiated in 5/35 HBV cases and in 10/55 HCV patients.A family screening was initiated in 22/35 HBV versus 13/55 HCV index patients and showed one additional HbsAg-positive and two anti-HCV-positive cases.Diagnostic procedures differed significantly between anti-HCV-positive and HbsAg-positive patients (P<0.001 for APRI, ultrasound, and family screening; P=0.03 for liver biopsy). CONCLUSION: Diagnostic procedures should be improved for hepatitis C-infected patients. The APRI index was only of limited value in the primary care setting.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/epidemiologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/epidemiologia , Atenção Primária à Saúde/estatística & dados numéricos , Adulto , Idoso , Atenção à Saúde/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Hepacivirus/imunologia , Hepatite B Crônica/diagnóstico , Hepatite C Crônica/diagnóstico , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Estudos Prospectivos
13.
J Med Chem ; 60(16): 7199-7205, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28749691

RESUMO

As a cellular bile acid sensor, farnesoid X receptor (FXR) participates in regulation of bile acid, lipid and glucose homeostasis, and liver protection. Clinical results have validated FXR as therapeutic target in hepatic and metabolic diseases. To date, potent FXR agonists share a negatively ionizable function that might compromise their pharmacokinetic distribution and behavior. Here we report the development and characterization of a high-affinity FXR modulator not comprising an acidic residue.


Assuntos
Imidazóis/farmacologia , Piridinas/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Colesterol 7-alfa-Hidroxilase/genética , Estabilidade de Medicamentos , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Imidazóis/síntese química , Imidazóis/química , Imidazóis/metabolismo , Masculino , Proteínas de Membrana Transportadoras/genética , Simulação de Acoplamento Molecular , PPAR alfa/genética , Piridinas/síntese química , Piridinas/química , Piridinas/metabolismo , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Relação Estrutura-Atividade , Zolpidem
14.
J Ultrasound Med ; 36(8): 1607-1615, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28370148

RESUMO

OBJECTIVES: Renal duplex sonography represents a standard noninvasive diagnostic procedure to demonstrate morphologic changes in acute kidney transplant dysfunction. We investigated whether a newly developed serial duplex index (SDI) can differentiate between acute cellular rejection and acute vascular rejection more effectively than the established Doppler parameters of the resistive index (RI) and pulsatility index (PI) in recently transplanted patients. METHODS: Serial duplex scans of patients with histologically proven acute tubular necrosis (n = 25), acute cellular rejection (n = 28), acute vascular rejection (n = 18), and normal graft function (n = 50, partially protocol biopsied) were retrospectively analyzed. For each patient, the RI, PI, and cortex-pelvis proportion (CPP) were included from the day of biopsy (t0) and 3 to 7 days before biopsy (t-1). The sequential CPP ratio (CPPt0 /CPPt-1 ), RI ratio (RIt0 /RIt-1 ), and PI ratio (PIt0 /Pit-1 ) were determined. The SDI was calculated as: RI ratio × PI ratio/CPP ratio. The diagnostic accuracy of the SDI was compared with that of the RI and PI ratios. RESULTS: Selected groups were statistically comparable in all routinely determined transplant parameters. The SDI was significantly different between patients with normal graft function, acute cellular rejection, and acute vascular rejection (P < .01, analysis of variance on ranks), whereas the RI and PI ratios were only significantly different between patients with normal graft function and acute vascular rejection (P < .05, analysis of variance on ranks). The indices' ranges were defined by the 95% confidence intervals between the allograft functions. CONCLUSIONS: The developed SDI was able to detect acute renal transplant rejection with greater sensitivity and specificity than the RI and PI ratios. Since the SDI distinguishes between acute tubular necrosis, acute cellular rejection, and acute vascular rejection, it might be a supportive tool to indicate renal biopsy.


Assuntos
Rejeição de Enxerto/diagnóstico por imagem , Transplante de Rim , Disfunção Primária do Enxerto/diagnóstico por imagem , Ultrassonografia Doppler Dupla/métodos , Doença Aguda , Diagnóstico Diferencial , Feminino , Humanos , Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
Cell Biol Int ; 40(3): 298-307, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26616141

RESUMO

Beneficial effects of erythropoietin (EPO) have been reported in acute kidney injury (AKI) when administered prior to induction of AKI. We studied the effects of EPO administration on renal function shortly after ischemic AKI. For this purpose, rats were subjected to renal ischemia for 30 min and EPO was administered at a concentration of 500 U/kg either i.v. as a single shot directly after ischemia or with an additional i.p. dose until 3 days after surgery. The results were compared with AKI rats without EPO application and a sham-operated group. Renal function was assessed by measurement of serum biochemical markers, histological grading, and using an isolated perfused kidney (IPK) model. Furthermore, we performed flow cytometry to analyze the concentration of endothelial progenitor cells (EPCs) in the peripheral blood and renal vessels. Following EPO application, there was only a statistically non-significant tendency of serum creatinine and urea to improve, particularly after daily EPO application. Renal vascular resistance and the renal perfusion rate were not significantly altered. In the histological analysis, acute tubular necrosis was only marginally ameliorated following EPO administration. In summary, we could not demonstrate a significant improvement in renal function when EPO was applied after AKI. Interestingly, however, EPO treatment resulted in a highly significant increase in CD133- and CD34-positive EPC both in the peripheral blood and renal vessels.


Assuntos
Injúria Renal Aguda/patologia , Vasos Sanguíneos/citologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Eritropoetina/farmacologia , Antígeno AC133/metabolismo , Injúria Renal Aguda/metabolismo , Animais , Creatinina/sangue , Modelos Animais de Doenças , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/metabolismo , Citometria de Fluxo , Taxa de Filtração Glomerular , Hematócrito , Isquemia/patologia , Rim/efeitos dos fármacos , Rim/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Ureia/sangue
16.
J Hepatol ; 62(6): 1256-64, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25617500

RESUMO

BACKGROUND & AIMS: Prevalence data for hepatitis B and C and an evaluation of a guideline based screening in the primary care setting are not yet available. We therefore implemented a hepatitis B surface antigen (HBsAg) and anti-hepatitis C virus (HCV) screening and developed guideline based screening strategies. METHODS: HBsAg, anti-HCV, and alanine aminotransferase (ALT) were included in a routine check-up together with a questionnaire covering 16 guideline adapted risk scenarios. Significant risk factors were identified by stepwise logistic regression. RESULTS: 51 private practices screened 21,008 patients. The HBsAg, anti-HCV, and HCV-RNA prevalence was 0.52%, 0.95%, and 0.43%, respectively. Infections were previously unknown in 85% and 65% of HBsAg and anti-HCV positive individuals, respectively. Sexual risk factors were under-reported, while the following scenarios were significantly associated with viral infections (Odds ratio [95% confidence interval]). HBV: Immigration (4.4 [2.9, 6.7]), infection in household (2.5 [1.2, 4.5]), male gender (1.6 [1.1, 2.4]). Male immigrants had a 2.1% HBsAg prevalence and 80% were unaware of the infection. HCV: IV drug use (384 [233, 644]), blood transfusion before 1992 (5.3 [3.5, 7.9]), immigration (2.4 [1.5, 3.6]). Presence of either one of the HBV related guideline defined risk scenarios or elevated ALT identified 82% of previously undiagnosed patients. Presence of one of the three significant HCV risk factors or elevated ALT levels diagnosed 83% of unknown HCV-RNA positive cases by screening only 26% of the population. CONCLUSIONS: Undiagnosed hepatitis B and C infections frequently exist in the primary care setting. Easy to apply guideline defined risk scenarios help to diagnose previously unknown infections.


Assuntos
Alanina Transaminase/sangue , Antígenos de Superfície da Hepatite B/sangue , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Alemanha/epidemiologia , Hepatite B/diagnóstico , Hepatite C/diagnóstico , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Prevalência , Atenção Primária à Saúde , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
17.
J Chem Inf Model ; 55(2): 284-93, 2015 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-25625859

RESUMO

The pharmacophore concept is commonly employed in virtual screening for hit identification. A pharmacophore is generally defined as the three-dimensional arrangement of the structural and physicochemical features of a compound responsible for its affinity to a pharmacological target. Given a number of active ligands binding to a particular target in the same manner, it can reasonably be assumed that they have some shared features, a common pharmacophore. We present a growing neural gas (GNG)-based approach for the extraction of the relevant features which we called PENG (pharmacophore elucidation by neural gas). Results of retrospective validation indicate an acceptable quality of the generated models. Additionally a prospective virtual screening for leukotriene A4 hydrolase (LTA4H) inhibitors was performed. LTA4H is a bifunctional zinc metalloprotease which displays both epoxide hydrolase and aminopeptidase activity. We could show that the PENG approach is able to predict the binding mode of the ligand by X-ray crystallography. Furthermore, we identified a novel chemotype of LTA4H inhibitors.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Epóxido Hidrolases/antagonistas & inibidores , Ensaios de Triagem em Larga Escala/métodos , Redes Neurais de Computação , Algoritmos , Aminopeptidases/química , Benchmarking , Cristalografia por Raios X , Epóxido Hidrolases/química , Humanos , Ligantes , Modelos Moleculares , Estudos Prospectivos , Ligação Proteica , Reprodutibilidade dos Testes , Termodinâmica
18.
Haematologica ; 100(1): 32-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25326431

RESUMO

Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34(+) hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34(+) hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34(+) cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential.


Assuntos
Diferenciação Celular , Células Eritroides/citologia , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Neurais/citologia , Biomarcadores/metabolismo , Metilação de DNA , Epigenômica , Células Eritroides/metabolismo , Sangue Fetal/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Neurais/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
J Clin Microbiol ; 52(8): 2855-60, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24871218

RESUMO

In the microbiology laboratory, there is an augmented need for rapid screening methods for the detection of bacteria in urine samples, since about two-thirds of these samples will not yield any bacteria or will yield insignificant growth when cultured. Thus, a reliable screening method can free up laboratory resources and can speed up the reporting of a negative urine result. In this study, we have evaluated the detection of leukocytes, bacteria, and a new sediment indicator, the "all small particles" (ASP), by an automated instrument, the iQ200 urine analyzer, to detect negative urine samples that can be excluded from culture. A coupled automated strip reader (iChem Velocity), enabling the detection of nitrite and leukocyte esterase, was tested in parallel. In total, 963 urine samples were processed through both conventional urine culture and the iQ200/iChem Velocity workstation. Using the data, a multivariate regression model was established, and the predicted specificity and the possible reduction in urine cultures were calculated for the indicators and their respective combinations (leukocytes plus bacteria plus ASP and leukocyte esterase plus nitrite). Among all options, diagnostic performance was best using the whole microscopic content of the sample (leukocytes plus bacteria plus ASP). By using a cutoff value of ≥ 10(4) CFU/ml for defining a positive culture, a given sensitivity of 95% resulted in a specificity of 61% and a reduction in urine cultures of 35%. By considering the indicators alone, specificity and the culture savings were both much less satisfactory. The regression model was also used to determine possible cutoff values for running the instrument as part of daily routine. By using a graphical representation of all combinations possible, we derived cutoff values for leukocyte, bacterial, and ASP count, which should enable the iQ200 microscope to screen out approximately one-third of the urine samples, significantly reducing the workload in the microbiology laboratory.


Assuntos
Automação Laboratorial/métodos , Bactérias/citologia , Bacteriúria/diagnóstico , Programas de Rastreamento/métodos , Microscopia/métodos , Urina/microbiologia , Hidrolases de Éster Carboxílico/análise , Humanos , Nitritos/análise , Sensibilidade e Especificidade , Urina/química
20.
Exp Dermatol ; 23(6): 395-400, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24689514

RESUMO

Human adipose-derived stroma cells (ADSCs) have successfully been employed in explorative therapeutic studies. Current evidence suggests that ADSCs are unevenly distributed in subcutaneous adipose tissue; therefore, the anatomical origin of ADSCs may influence clinical outcomes. This study was designed to investigate proliferation and differentiation capacities of ADSCs from the gluteal and abdominal depot of 8 females. All had normal BMI (22.01 ± 0.39 kg/m(2) ) and waist circumference (81.13 ± 2.33 cm). Examination by physicians and analysis of 31 laboratory parameters did not reveal possibly confounding medical disorders. Gluteal and abdominal adipose tissue was sampled by en bloc resection on day 7 (±1) after the last menses. Histological examination did not reveal significant depot-specific differences. As assessed by BrdU assay, proliferation of cells from both depots was similar after 24 h and analysis of 15 cell surface markers by flow cytometry identified the isolated cells as ADSCs, again without depot-specific differences. ADSCs from both depots differentiated poorly to chondroblasts. Gluteal ADSCs displayed significantly higher adipogenic differentiation potential than abdominal cells. Osteogenic differentiation was most pronounced in gluteal cells, whereas differentiation of abdominal ADSCs was severely impaired. Our data demonstrate a depot-specific difference in ADSC differentiation potential with abdominal cells failing to meet the criteria of multipotent ADSCs. This finding should be taken into account in future explorations of ADSC-derived therapeutic strategies.


Assuntos
Abdome , Adipogenia/fisiologia , Nádegas , Osteogênese/fisiologia , Células Estromais/citologia , Células Estromais/fisiologia , Gordura Subcutânea/citologia , Adipócitos/citologia , Adipócitos/fisiologia , Adulto , Biópsia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Feminino , Humanos , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/fisiologia , Osteoblastos/citologia , Osteoblastos/fisiologia
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