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1.
Front Psychiatry ; 11: 794, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903474

RESUMO

BACKGROUND: Among people living in detention, substance use is highly prevalent, including opioid dependence. Opioid agonist treatment (OAT) has been established as an evidence-based, first-line treatment for opioid dependence. Despite high prevalence of opioid dependence, conclusive data regarding its prevalence and the OAT practice in German prisons is scarce; rather, the existing data widely diverges concerning the rates of people in detention receiving OAT. MATERIALS AND METHODS: We conducted a cross-sectional survey of all detention facilities in Berlin. On the date of data collection, a full census of the routine records was completed based on the medical documentation system. For each opioid dependent individual, we extracted sociodemographic data (i.e., age, sex, and non-/German nationality, whether people experienced language-related communication barriers), information about OAT, comorbidities (HIV, hepatitis C, schizophrenia), and the detention center, as well as the anticipated imprisonment duration and sentence type. The data was first analyzed descriptively and secondly in an evaluative-analytical manner by analyzing factors that influence the access to OAT of people living in detention. RESULTS: Among the 4,038 people in detention in the Berlin custodial setting under investigation, we identified a 16% prevalence of opioid dependence. Of the opioid-dependent individuals, 42% received OAT; 31% were treated with methadone, 55% were treated with levomethadone, and 14% were treated with buprenorphine. Access to OAT seemed mainly dependent upon initial receipt of OAT at the time of imprisonment, detention duration, the prisons in which individuals were detained, German nationality, and sex. The overall prevalence of HIV was 4-8%, hepatitis C was 31-42%, and schizophrenia was 5%. CONCLUSIONS: The prevalence of opioid dependence and access to OAT remains a major health issue in the custodial setting. OAT implementation must be especially intensified among male, non-German, opioid-dependent individuals with a short detention period. Treatment itself must be diversified regarding the substances used for OAT, and institutional treatment differences suggest the need for a consistent treatment approach and the standardized implementation of treatment guidelines within local prison's standard operating procedures. Testing for infectious diseases should be intensified among opioid-dependent people living in detention to address scarcely known infection statuses and high infection rates.

2.
Sensors (Basel) ; 20(13)2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32635611

RESUMO

Geological objects are characterized by a high complexity inherent to a strong compositional variability at all scales and usually unclear class boundaries. Therefore, dedicated processing schemes are required for the analysis of such data for mineralogical mapping. On the other hand, the variety of optical sensing technology reveals different data attributes and therefore multi-sensor approaches are adapted to solve such complicated mapping problems. In this paper, we devise an adapted multi-optical sensor fusion (MOSFus) workflow which takes the geological characteristics into account. The proposed processing chain exhaustively covers all relevant stages, including data acquisition, preprocessing, feature fusion, and mineralogical mapping. The concept includes (i) a spatial feature extraction based on morphological profiles on RGB data with high spatial resolution, (ii) a specific noise reduction applied on the hyperspectral data that assumes mixed sparse and Gaussian contamination, and (iii) a subsequent dimensionality reduction using a sparse and smooth low rank analysis. The feature extraction approach allows one to fuse heterogeneous data at variable resolutions, scales, and spectral ranges and improve classification substantially. The last step of the approach, an SVM classifier, is robust to unbalanced and sparse training sets and is particularly efficient with complex imaging data. We evaluate the performance of the procedure with two different multi-optical sensor datasets. The results demonstrate the superiority of this dedicated approach over common strategies.

3.
Behav Sci Law ; 38(5): 471-481, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32633430

RESUMO

The risk of violent behavior is known to be higher for patients who suffer from a severe mental disorder. However, specific prediction tools for clinical work in prison psychiatry are lacking. In this single-center study, two violence risk assessment tools (Forensic Psychiatry and Violence Tool, "FoVOx," and Mental Illness and Violence Tool, "OxMIV") were applied to a prison hospital population with a primary psychotic or bipolar disorder and subsequently compared. The required information on all items of both tools was obtained retrospectively for a total of 339 patients by evaluation of available patient files. We obtained the median and inter-quartile range for both FoVOx and OxMIV, and their rank correlation coefficient along with 95% confidence intervals (CIs)-for the full cohort, as well as for cohort subgroups. The two risk assessment tools were strongly positively correlated (Spearman correlation = 0.83; 95% CI = 0.80-0.86). Such a high correlation was independent of nationality, country of origin, type of detention, schizophrenia-spectrum disorder, previous violent crime and alcohol use disorder, where correlations were above 0.8. A lower correlation was seen with patients who were 30 years old or more, married, with affective disorder and with self-harm behavior, and also in patients without aggressive behavior and without drug use disorder. Both risk assessment tools are applicable as an adjunct to clinical decision making in prison psychiatry.


Assuntos
Psiquiatria Legal/instrumentação , Prisioneiros/psicologia , Medição de Risco/métodos , Violência/psicologia , Adolescente , Adulto , Idoso , Berlim/epidemiologia , Transtorno Bipolar/diagnóstico , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Prisioneiros/estatística & dados numéricos , Transtornos Psicóticos/diagnóstico , Estudos Retrospectivos , Violência/estatística & dados numéricos
4.
J Chem Phys ; 152(6): 064701, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32061222

RESUMO

Model studies on the adsorption of simple amino acids on single-crystalline substrates provide the basis for understanding the interactions of more complex biomolecules with inorganic materials. In this study, the adsorption and thermal stability of cysteine on Pt(111) and on monolayer FeO(111)/Pt(111) and thick Fe3O4(111)/Pt(111) films have been investigated in ultrahigh vacuum by means of x-ray photoelectron spectroscopy, infrared reflection absorption spectroscopy, and temperature-programmed desorption. At low adsorption temperature (160 K), cysteine stays intact on all studied surfaces. However, the thermal stability differs dramatically. Decomposition via dehydrogenation, decarbonylation/decarboxylation, and deamination starts already below room temperature on Pt(111). By contrast, adsorbed cysteine is stable up to 500 K on Fe3O4(111) and then gets oxidized in a redox reaction involving the Fe3O4 substrate. FeO(111)/Pt(111) is a special case, where decarbonylation of cysteine occurs below room temperature, which is most likely initiated by a structural modification and concomitant charge transfer at the Pt-FeO interface induced by the carboxyl group of the adsorbed cysteine. The experimental results suggest that cysteine binds to the surfaces with the carboxyl group on the iron oxides and with the carboxyl and amino groups on Pt(111).

5.
Sensors (Basel) ; 19(12)2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31234309

RESUMO

Rapid, efficient and reproducible drillcore logging is fundamental in mineral exploration. Drillcore mapping has evolved rapidly in the recent decade, especially with the advances in hyperspectral spectral imaging. A wide range of imaging sensors is now available, providing rapidly increasing spectral as well as spatial resolution and coverage. However, the fusion of data acquired with multiple sensors is challenging and usually not conducted operationally. We propose an innovative solution based on the recent developments made in machine learning to integrate such multi-sensor datasets. Image feature extraction using orthogonal total variation component analysis enables a strong reduction in dimensionality and memory size of each input dataset, while maintaining the majority of its spatial and spectral information. This is in particular advantageous for sensors with very high spatial and/or spectral resolution, which are otherwise difficult to jointly process due to their large data memory requirements during classification. The extracted features are not only bound to absorption features but recognize specific and relevant spatial or spectral patterns. We exemplify the workflow with data acquired with five commercially available hyperspectral sensors and a pair of RGB cameras. The robust and efficient spectral-spatial procedure is evaluated on a representative set of geological samples. We validate the process with independent and detailed mineralogical and spectral data. The suggested workflow provides a versatile solution for the integration of multi-source hyperspectral data in a diversity of geological applications. In this study, we show a straight-forward integration of visible/near-infrared (VNIR), short-wave infrared (SWIR) and long-wave infrared (LWIR) data for sensors with highly different spatial and spectral resolution that greatly improves drillcore mapping.

6.
Front Psychiatry ; 10: 264, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31065245

RESUMO

Background: Although there is evidence that individuals who suffer from severe mental disorders are at higher risk for aggressive behavior, only a minority eventually become violent. In 2017, Fazel et al. developed a risk calculator (Oxford Mental Illness and Violence tool, OxMIV) to identify the risk of violent crime in patients with mental disorders. For the first time, we tested the predictive validity of the OxMIV in the department of psychiatry at the prison hospital in Berlin, Germany, and presented findings from our internal validation. Materials and Methods: We designed a cohort study with 474 patients aged 16-65 years old who met the inclusion criteria of schizophrenia-spectrum or bipolar disorder and classified the patients into two groups: a violent group with 191 patients and a nonviolent group with 283 patients. Violence was defined as the aggressive behavior of a patient with the necessity of special observation. We obtained all the required information retrospectively through patient files, applied the OxMIV tool on each subject, and compared the results of both groups. Sensitivity, specificity, and positive/negative predictive values were determined. We used logistic regression including variable selection and internal validation to identify relevant predictors of aggressive behavior in our cohort. Results: The OxMIV score was significantly higher in the violent group [median 4.21%; Interquartile range (IQR) 8.51%] compared to the nonviolent group (median 1.77%; IQR 2.01%; p < 0.0001). For the risk of violent behavior, using the 5% cutoff for "increased risk," the sensitivity was 44%, and the specificity was 89%, with a positive predictive value of 72% and a negative predictive value of 70%. Applying logistic regression, four items were statistically significant in predicting violent behavior: previous violent crime (adjusted odds ratio 5.29 [95% CI 3.10-9.05], p < 0.0001), previous drug abuse (1.80 [1.08-3.02], p = 0.025), and previous alcohol abuse (1.89 [1.21-2.95], p = 0.005). The item recent antidepressant treatment (0.28 [0.17-0.47]. p < 0.0001) had a statistically significant risk reduction effect. Conclusions: In our opinion, the risk assessment tool OxMIV succeeded in predicting violent behavior in imprisoned psychiatric patients. As a result, it may be applicable for identification of patients with special needs in a prison environment and, thus, improving prison safety.

7.
Sensors (Basel) ; 19(10)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091700

RESUMO

Due to the rapidly increasing use of energy-efficient technologies, the need for complex materials containing rare earth elements (REEs) is steadily growing. The high demand for REEs requires the exploration of new mineral deposits of these valuable elements, as recovery by recycling is still very low. Easy-to-deploy sensor technologies featuring high sensitivity to REEs are required to overcome limitations by traditional techniques, such as X-ray fluorescence. We demonstrate the ability of laser-induced fluorescence (LIF) to detect REEs rapidly in relevant geological samples. We introduce two-dimensional LIF mapping to scan rock samples from two Namibian REE deposits and cross-validate the obtained results by employing mineral liberation analysis (MLA) and hyperspectral imaging (HSI). Technique-specific parameters, such as acquisition speed, spatial resolution, and detection limits, are discussed and compared to established analysis methods. We also focus on the attribution of REE occurrences to mineralogical features, which may be helpful for the further geological interpretation of a deposit. This study sets the basis for the development of a combined mapping sensor for HSI and 2D LIF measurements, which could be used for drill-core logging in REE exploration, as well as in recovery plants.

8.
Dtsch Arztebl Int ; 115(48): 808-814, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30642429

RESUMO

BACKGROUND: Infectious diseases, substance dependencies, and dental diseases are the most important health problems affecting incarcerated persons. In Germany, for example, prisoners are 48 to 69 times more likely to be infected with the hepatitis C virus (HCV) than the general population, and 7 to 12 times more likely to be infected with the human immunodeficiency virus (HIV). The prevalence of mental illnesses is also markedly higher in the incarcerated than in the general population. METHODS: This review is based on pertinent publications retrieved by a selective search in two databases (PubMed and Google Scholar) for any of the terms "health care," "primary health care," "mental health care"; "infectious disease," "opioid maintenance treatment," and "severe mental disorder" in conjunction with "prison," "jail," "detention," and "incarceration." RESULTS: Among prisoners in German prisons, approximately 20% consume heroin, 20-50% suffer from alcohol dependency and abuse, and 70-85% smoke. The prevalence of tuberculosis in German prisons in 2002 was 0.1%. The provision of needles to incarcerated persons has a preventive effect on infection with hepatitis C, hepatitis B, and HIV, yet programs of this type have been discontinued in most penal facilities. In a systematic review, psychotic disorders were found in 3.6% (95% confidence interval [CI]: [3.1; 4.2]) of male inmates and 3.9% [95% CI: 2.7; 5.0] of female inmates. 25% of incarcerated persons suffer from attention-deficit-hyperac- tivity disorder. Persons recently released from prison have an above average mortality, largely due to drug intoxication. CONCLUSION: An analysis of medical prescribing data reveals deficiencies in the provision of HCV treatment to all affected persons and in the provision of substitution treatment to persons with opiate dependency. In view of the known risks associated with imprisonment, greater emphasis should be placed on the provision of treatment for infectious diseases, substance dependencies, and mental illness, both in prison and in outpatient care after release.


Assuntos
Doenças Transmissíveis/terapia , Atenção à Saúde/organização & administração , Atenção à Saúde/estatística & dados numéricos , Transtornos Mentais/terapia , Transtornos Relacionados ao Uso de Opioides/terapia , Prisioneiros/estatística & dados numéricos , Prisões/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Fatores de Risco
9.
Environ Toxicol ; 30(8): 956-67, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24615900

RESUMO

There is increasing worldwide interest in developing of markers for tumor diagnosis and identification of individuals who are at high cancer risk. Cancer, like other diseases accompanied by metabolic disorders, causes characteristic effects on cell turnover rate, activity of modifying enzymes, and RNA/DNA modifications. This results in an increased excretion of modified nucleosides in cancer patients. Therefore, for many years modified nucleosides have been suggested as tumor markers. The aim of the study was to elucidate further the usefulness of urinary nucleosides as possible markers at early detection of cancer in persons which are exposed against tumor promoting influences during their working life. Uranium miners are exposed to many kinds of pollutants that can cause health damage even lead to carcinogenesis. We analyzed modified nucleosides in urine samples from 92 miners who are at high risk for lung cancer to assess the levels of nucleosides by a multilayer perceptron (MLP) classifier - a neural network model. Eighteen nucleosides/metabolites were detected with reversed-phase high-pressure liquid chromatography (RP-HPLC). A valid set of urinary metabolites were selected and multivariate statistical technique of multilayer perceptron neural network were applied. In a previous study, MLP shows a sensitivity and specificity of 97 and 85%, respectively. MLP classification including the most relevant markers/nucleosides clearly demonstrates the elevation of RNA metabolism in miners, which is associated with possible malignant disease. We found that there were 30 subjects with early health disorders among 92 uranium workers based on MLP technique using modified nucleosides. The combination of RP-HPLC analysis of modified nucleosides and subsequent MLP analyses represents a promising tool for the development of a non-invasive prediction system and may assist in developing management and surveillance procedures.


Assuntos
Biomarcadores Tumorais/urina , Neoplasias Pulmonares/urina , Mineração , Nucleosídeos/urina , Exposição Ocupacional/efeitos adversos , Urânio/toxicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida de Alta Pressão , Creatinina/análise , Feminino , Alemanha , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Medição de Risco , Urânio/urina , Ácido Úrico/análise , Adulto Jovem
10.
Phys Chem Chem Phys ; 14(22): 8217-23, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22546738

RESUMO

Terephthalic acid on metal surfaces is a system of high interest for interfacial layers as well as for use in generating surface nanostructures by supramolecular self-assembly. Here we demonstrate structural transitions upon compression of the first layer as well as a significant transition from a flat lying chemisorbed first monolayer to a standing second layer. The second layer structure is stable at 150 °C, but a weakly bound state is observed to desorb molecularly below that temperature, likely a transient mobile state during annealing. Molecular resolution scanning tunnelling microscopy is complemented by X-ray photoelectron spectroscopy and thermal desorption spectroscopy in this study. These results provide general insight in the development of self-assembled organic thin films at surfaces, especially with regard to the nature of the metal/organic interface and growth transitions to maximize first layer packing and obtain a second layer that bridges commensurability with the substrate and a more bulk-like structure.

11.
Z Med Phys ; 15(2): 101-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16008079

RESUMO

Artificial neural nets were used to determine the Young's modulus and spatial load distribution in articular cartilage by means of T2-weighted MR imaging. MR images were obtained in vitro (ex vivo?) from the joints of sheep of different ages (3 months, 9 months, 15 months, 1.5 years, 5 years, 5.5 years) and pigs (4 and 6 months) with a Bruker AMX 300 (7 T) spectrometer equipped with a micro-imaging unit. The knee of a 29-year-old male volunteer was studied in vivo under mechanical load using a clinical Siemens Vision MRT (1.5 T). The load of the cartilage is understood as a non-linear image transformation of loaded versus unloaded images. The artificial neural net was used to recognize given reference pixels of the unloaded cartilage within the image of the loaded cartilage. The Young's modulus was calculated from the local strain and the external pressure using the Hooke's law. With this method, the average Young's modulus was obtained in relationship to the biological age of the cartilage. The investigated age interval showed a progressive increase of 0.5 +/- 0.3 MPa per year. These results are consistent with published results. As shown in this pilot study, the method of neural nets allows the visualization of the spatial load distribution within the articular cartilage.


Assuntos
Cartilagem Articular/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa , Envelhecimento , Animais , Cartilagem Articular/crescimento & desenvolvimento , Ovinos
12.
Z Med Phys ; 15(1): 45-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15830784

RESUMO

The present paper describes a novel method to obtain information on the degree of order of the collagen network of the knee meniscal cartilage by means of a single clinical MRI. Images were obtained from 34 healthy volunteers aged between 6 and 76 years as well as from one patient with clinically-diagnosed arthrosis at the age of 32 and 37 years. A Siemens Vision (1.5 T) MRT with TR=750 ms, TE=50 ms, FoV=160 mm, and Matrix 512x512 was used for this purpose. The MR signal intensities of the cartilage were read out along slices with constant height above the subchondral bone and plotted versus the actual angle to the external magnetic field. The obtained intensity curves were fitted by a model distribution, and the degree of order of the collagen fibers was calculated. For the knee meniscal cartilage, there was an age-dependency of the degree of order and a significant deviation of the volunteer with arthrosis from the normal curve. The results are discussed in view of the arcade model and of a possible use of non-invasive clinical MRT for the detection of early arthrotic changes of cartilage.


Assuntos
Cartilagem Articular/química , Cartilagem Articular/crescimento & desenvolvimento , Colágeno/química , Adolescente , Adulto , Idoso , Envelhecimento , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/patologia , Criança , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Z Med Phys ; 15(4): 265-72, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16422355

RESUMO

Cancer diseases are the focus of intense research due to their frequent occurrence. It is known from the literature that serum proteins are changed in the case of malignant processes. Changes of albumin conformation, transport efficiency, and binding characteristics can be determined by electron spin resonance spectroscopy (ESR). The present study analysed the binding/dissociation function of albumin with an ESR method using 16-doxyl stearate spin probe as reporter molecule and ethanol as modifier of hydrophobic interactions. Native and frozen plasma of healthy donors (608 samples), patients with malignant diseases (423 samples), and patients with benign conditions (221 samples) were analysed. The global specificity was 91% and the sensitivity 96%. In look-back samples of 27 donors, a malignant process could be detected up to 30 months before clinical diagnosis. To recognise different entities of malignant diseases from the ESR spectra, Artificial neural networks were implemented. For 48 female donors with breast cancer, the recognition specificity was 85%. Other carcinoma entities (22 colon, 18 prostate, 12 stomach) were recognised with specificities between 75% and 84%. Should these specificity values be reproduced in larger studies, the described method could be used as a new specific tumour marker for the early detection of malignant processes. Since transmission of cancer via blood transfusion cannot be excluded as yet, the described ESR method could also be used as a quality test for plasma products.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Neoplasias/diagnóstico , Albumina Sérica/ultraestrutura , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Redes Neurais de Computação , Sensibilidade e Especificidade
14.
Antimicrob Agents Chemother ; 48(11): 4084-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15504825

RESUMO

The purpose of this study was to establish a reliable and cost-effective microplate proliferation assay for in vitro antimicrobial testing of bone cement samples. Cement samples devoid of antimicrobial agents, loaded with 2% gentamicin or with different concentrations of high-porosity silver, were incubated in a 96-well microplate with several staphylococcal, Pseudomonas aeruginosa, and Enterococcus faecium isolates exhibiting different susceptibilities to gentamicin. After being rinsed, the samples were brought into a soy medium in which adherent cells on the cement surface either were killed by the antimicrobial surface or started to release clonal counterparts. The medium was monitored in real time by recording a time proliferation curve for each well. Microplate testing revealed no antibacterial effect of plain bone cement. The antibacterial activity of gentamicin-loaded bone cement was shown by the microplate test to depend on the gentamicin susceptibilities of the strains. The effect of high-porosity silver was dose dependent. Bactericidal activity against all tested strains was found for bone cement loaded with 1% high-porosity silver. The accuracy of this new proliferation assay was shown by the high correlation between the types of proliferation curves and antibiotic susceptibility. In contrast to routine agar diffusion testing, it assesses the dynamic response of microorganisms to antimicrobial agents in biomaterials and allows high-throughput screening and detection of antimicrobial properties of poorly water-soluble compounds like silver.


Assuntos
Anti-Infecciosos/farmacologia , Cimentos Ósseos/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/administração & dosagem , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Biofilmes , Enterococcus faecium/efeitos dos fármacos , Gentamicinas/farmacologia , Resistência a Meticilina , Testes de Sensibilidade Microbiana , Polimetil Metacrilato , Porosidade , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/administração & dosagem , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos
15.
Biomaterials ; 25(18): 4383-91, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15046929

RESUMO

Infections with multiresistant bacteria have become a serious problem in joint arthroplasty. This study reports about in vitro antibacterial activity against multiresistant bacteria and in vitro cytotoxicity of polymethylmetacrylate bone cement loaded with metallic silver particles with a size of 5-50 nm called NanoSilver. In vitro antibacterial activity against S. epidermidis, methicillin-resistant S. epidermidis (MRSE), and methicillin-resistant S. aureus (MRSA) was studied by microplate proliferation tests. Quantitative elution testing and qualitative ongrowth of human osteoblasts was done to study in vitro cytotoxicity. Only NanoSilver cement showed high-antibacterial activity against all strains, including MRSE and MRSA. Gentamicin cement was not effective against MRSA and MRSE due to the high-level gentamicin resistance of the tested strains. Plain cement did not inhibit proliferation of any strains. There was no significant difference regarding in vitro cytotoxicity between NanoSilver and the non-toxic control. Cytotoxicity of cement loaded with silver salts made this kind of silver unsuitable for all day clinical use in the past. This new form of silver called NanoSilver was free of in vitro cytotoxicity and showed high effectiveness against multiresistant bacteria. If the results can be confirmed in vivo NanoSilver may have a high interest in joint arthroplasty.


Assuntos
Fibroblastos/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Polimetil Metacrilato/administração & dosagem , Polimetil Metacrilato/toxicidade , Prata/administração & dosagem , Prata/toxicidade , Staphylococcus/efeitos dos fármacos , Animais , Antibacterianos/administração & dosagem , Antibacterianos/toxicidade , Biofilmes/efeitos dos fármacos , Cimentos Ósseos/farmacologia , Cimentos Ósseos/toxicidade , Linhagem Celular , Sistemas de Liberação de Medicamentos/métodos , Humanos , Camundongos , Nanotubos/química , Nanotubos/toxicidade , Staphylococcus/citologia , Resultado do Tratamento
16.
FEMS Immunol Med Microbiol ; 34(2): 159-67, 2002 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-12381468

RESUMO

Streptococcus pyogenes (GAS) causes about 90% of streptococcal human infections while group C (GCS) and G (GGS) streptococci can be pathogenic for different mammalians. Especially the human pathogenic GCS and GGS, Streptococcus dysgalactiae, subsp. equisimilis, account for 5-8% of the human streptococcal diseases like wound infections, otitis media, purulent pharyngitis and also streptococcal toxic shock syndrome. A defined superantigen so far was not identified in GCS and GGS strains. In the present investigation we screened DNA of GCS and GGS human isolates for the presence of genes for streptococcal pyrogenic exotoxins (spe) by hybridisation with probes that stand for the GAS genes speA, speC, speZ (smeZ), speH, speG, speI, speJ and ssa. In many GCS and GGS strains we found positive reactions with the probes speG, speJ and ssa, but not with the probes for the remaining genes under investigation. PCR amplification with subsequent sequence analysis of the PCR fragments revealed only the presence of the gene speG in GCS and GGS strains, while no DNA fragments specific for speJ and ssa could be amplified. Additionally, the upstream and downstream regions flanking speG in GGS strain 39072 were sequenced. Remarkable differences were found in the neighbourhood of speG between GAS and GGS sequences. Downstream of speG we identified in strain GGS 39072 two new open reading frames encoding proteins with no similarity to protein sequences accessible in the databases so far. In the compared GAS strains SF370 and MGAS8232, this segment, apart from some small fragments, had been deleted. Our analysis suggests that a gene transfer from GGS to GAS has preceded following deletion of the two genes orf1 and orf2 in GAS.


Assuntos
Proteínas de Bactérias , Exotoxinas/genética , Genes Bacterianos , Proteínas de Membrana , Streptococcus/genética , Superantígenos/genética , Sequência de Aminoácidos , Mapeamento Cromossômico , Exotoxinas/isolamento & purificação , Humanos , Hibridização In Situ , Modelos Genéticos , Dados de Sequência Molecular , Sinais Direcionadores de Proteínas , Análise de Sequência de DNA , Análise de Sequência de Proteína , Streptococcus/patogenicidade , Streptococcus pyogenes/genética , Streptococcus pyogenes/isolamento & purificação
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