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1.
Arch Orthop Trauma Surg ; 142(7): 1413-1420, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33507378

RESUMO

BACKGROUND: The Samilson-Prieto classification (SPC) depending on the humeral osteophyte length on a-pX-rays today is widely used to classify glenohumeral osteoarthritis in general. For treatment planning and prognosis, the patho-morphology of the glenoid and static posterior subluxation of the humeral head classified according to Walch is of much higher importance. Here, usually a CT or MRI scan is required for a correct classification. A possible correlation between both classifications is poorly explored. Without it, the complexity of the case might be mis-interpreted using the SPC. The aim of this study was to investigate such a correlation, i.e. whether it correlates with the glenoid deformity and degree of humeral head subluxation. PATIENTS AND METHODS: Radiological datasets (X-ray and CT or MRI) of 352 patients with primary OA of the shoulder were evaluated by two observers experienced in shoulder surgery. For the Samilson-Prieto classification, true a-p shoulder radiographs and for the modified Walch classification CT or MRI scans in the axial plane were interpreted using a validated method. To investigate a correlation between both classifications, the Fisher's exact test was used. For the interobserver reliability, the weighted kappa coefficient κ was determined. RESULTS: For the Walch classification, both observers found a similar percentage for the different types, with decreasing numbers from normal (type A1) to severely altered glenoids In the Samilson-Prieto classification, OA grade I was predominant, while grade II and III showed a relatively equal distribution. Interobserver reliability was high both for the Walch classification with a κ 0.923 (95% confidence interval 0.892; 0.954) and) for the SPC with a κ 0.88 (95% confidence interval 0.843; 0.916). A correlation between the two classifications in Fischer's exact test could not be shown (p = 0.584). DISCUSSION: Since there is no correlation between both, using the Samilson-Prieto classification alone might miss relevant prognostic factors in gleno-humeral OA. Adequate imaging of the glenoid morphology also in the axial plane is absolutely mandatory to understand the complexity and chose the right treatment for each patient. LEVEL OF EVIDENCE: Study of Diagnostic Test-Level II.


Assuntos
Cavidade Glenoide , Luxações Articulares , Osteoartrite , Articulação do Ombro , Humanos , Cabeça do Úmero , Osteoartrite/diagnóstico por imagem , Osteoartrite/cirurgia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Escápula , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/cirurgia
2.
Sensors (Basel) ; 20(21)2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33114281

RESUMO

In recent years, lanthanide-doped nanothermometers have been mainly used in thin films or dispersed in organic solvents. However, both approaches have disadvantages such as the short interaction lengths of the active material with the pump beam or complicated handling, which can directly affect the achievable temperature resolution. We investigated the usability of a polymer fiber doped with upconversion nanocrystals as a thermometer. The fiber was excited with a wavelength stabilized diode laser at a wavelength of 976 nm. Emission spectra were recorded in a temperature range from 10 to 35 ∘C and the thermal emission changes were measured. Additionally, the pump power was varied to study the effect of self-induced heating on the thermometer specifications. Our fiber sensor shows a maximal thermal sensitivity of 1.45%/K and the minimal thermal resolution is below 20 mK. These results demonstrate that polymer fibers doped with nanocrystals constitute an attractive alternative to conventional fluorescence thermometers, as they add a long pump interaction length while also being insensitive to strong electrical fields or inert to bio-chemical environments.

3.
Sensors (Basel) ; 20(15)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32707919

RESUMO

Lab-on-a-Chip (LoC) devices combining microfluidic analyte provision with integrated optical analysis are highly desirable for several applications in biological or medical sciences. While the microfluidic approach is already broadly addressed, some work needs to be done regarding the integrated optics, especially provision of highly integrable laser sources. Polymer optical fiber (POF) lasers represent an alignment-free, rugged, and flexible technology platform. Additionally, POFs are intrinsically compatible to polymer microfluidic devices. Home-made Rhodamine B (RB)-doped POFs were characterized with experimental and numerical parameter studies on their lasing potential. High output energies of 1.65 mJ, high slope efficiencies of 56 % , and 50 % -lifetimes of ≥900 k shots were extracted from RB:POFs. Furthermore, RB:POFs show broad spectral tunability over several tens of nanometers. A route to optimize polymer fiber lasers is revealed, providing functionality for a broad range of LoC devices. Spectral tunability, high efficiencies, and output energies enable a broad field of LoC applications.

4.
J Interv Cardiol ; 29(6): 594-600, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27687514

RESUMO

AIMS: Initial studies of catheter-based renal arterial sympathetic denervation to lower blood pressure in resistant hypertensive patients renewed interest in the sympathetic nervous system's role in the pathogenesis of hypertension. However, the SYMPLICITY HTN-3 study failed to meet its prespecified blood pressure lowering efficacy endpoint. To date, only a limited number of studies have described the microanatomy of renal nerves, of which, only two involve humans. METHODS AND RESULTS: Renal arteries were harvested from 15 cadavers from the Klinikum Osnabruck and Schuchtermann Klinik, Bad Rothenfelde. Each artery was divided longitudinally in equal thirds (proximal, middle, and distal), with each section then divided into equal superior, inferior, anterior, and posterior quadrants, which were then stained. Segments containing no renal nerves were given a score value = 0, 1-2 nerves with diameter <300 µm a score = 1; 3-4 nerves or nerve diameter 300-599 µm a score = 2, and >4 nerves or nerve diameter ≥600 µm a score = 3. A total of 22 renal arteries (9 right-sided, 13 left-sided) were suitable for examination. Overall, 691 sections of 5 mm thickness were prepared. Right renal arteries had significantly higher mean innervation grade (1.56 ± 0.85) compared to left renal arteries (1.09 ± 0.87) (P < 0.001). Medial (1.30 ± 0.59) and distal (1.39 ± 0.62) innervation was higher than the proximal (1.17 ± 0.55) segments (p < 0.001). When divided in quadrants, the anterior (1.52 ± 0.96) and superior (1.71 ± 0.89) segments were more innervated compared to posterior (0.96 ± 0.72) and inferior (0.90 ± 0.68) segments (P < 0.001). CONCLUSIONS: That the right renal artery has significantly higher innervation scores than the left. The anterior and superior quadrants of the renal arteries scored higher in innervation than the posterior and inferior quadrants did. The distal third of the renal arteries are more innervated than the more proximal segments. These findings warrant further evaluation of the spatial innervation patterns of the renal artery in order to understand how it may enhance catheter-based renal arterial denervation procedural strategy and outcomes. CONDENSED ABSTRACT: The SYMPLICITY HTN-3 study dealt a blow to the idea of the catheter-based renal arterial sympathetic denervation. We investigated the location and patterns of periarterial renal nerves in cadaveric human renal arteries. To quantify the density of the renal nerves we created a novel innervation score. On average the right renal arteries were significantly more densely innervated than the left renal arteries, the anterior and superior segments were significantly more innervated compared to the posterior and inferior segments, absolute innervation scores in the proximal third of the left or right renal arteries were always lower when compared to distal segments. These findings may enhance catheter-based renal arterial denervation procedural strategy and outcomes.


Assuntos
Hipertensão/cirurgia , Artéria Renal , Simpatectomia , Sistema Nervoso Simpático/cirurgia , Idoso , Pressão Sanguínea/fisiologia , Cadáver , Feminino , Humanos , Rim/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Modelos Anatômicos , Artéria Renal/inervação , Artéria Renal/patologia , Simpatectomia/efeitos adversos , Simpatectomia/métodos
5.
Int J Mol Sci ; 16(2): 3856-69, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25679447

RESUMO

The multifocal nature of prostate cancer (PCa) creates a challenge to patients' outcome prediction and their clinical management. An approach that scrutinizes every cancer focus is needed in order to generate a comprehensive evaluation of the disease, and by correlating to patients' clinico-pathological information, specific prognostic biomarker can be identified. Our study utilized the Affymetrix SNP 6.0 Genome-wide assay to investigate forty-three fresh frozen PCa tissue foci from twenty-three patients. With a long clinical follow-up period that ranged from 2.0-9.7 (mean 5.4) years, copy number variation (CNV) data was evaluated for association with patients' PSA status during follow-up. From our results, the loss of unique genes on 10q23.31 and 10q23.2-10q23.31 were identified to be significantly associated to PSA recurrence (p < 0.05). The implication of PTEN and FAS loss (10q23.31) support previous reports due to their critical roles in prostate carcinogenesis. Furthermore, we hypothesize that the PAPSS2 gene (10q23.2-10q23.31) may be functionally relevant in post-operative PSA recurrence because of its reported role in androgen biosynthesis. It is suggestive that the loss of the susceptible region on chromosome 10q, which implicates PTEN, FAS and PAPSS2 may serve as genetic predictors of PSA recurrence after radical prostatectomy.


Assuntos
Complexos Multienzimáticos/genética , Recidiva Local de Neoplasia/genética , PTEN Fosfo-Hidrolase/genética , Antígeno Prostático Específico/análise , Neoplasias da Próstata/genética , Sulfato Adenililtransferase/genética , Receptor fas/genética , Idoso , Cromossomos Humanos Par 10/genética , Variações do Número de Cópias de DNA , Deleção de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Antígeno Prostático Específico/metabolismo , Prostatectomia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/cirurgia
6.
Int J Mol Sci ; 14(6): 11816-29, 2013 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-23736690

RESUMO

Prostate cancer is widely observed to be biologically heterogeneous. Its heterogeneity is manifested histologically as multifocal prostate cancer, which is observed more frequently than unifocal prostate cancer. The clinical and prognostic significance of either focal cancer type is not fully established. To investigate prostate cancer heterogeneity, the genetic profiles of multifocal and unifocal prostate cancers were compared. Here, we report observations deduced from tumor-tumor comparison of copy number alteration data of both focal categories. Forty-one fresh frozen prostate cancer foci from 14 multifocal prostate cancers and eight unifocal prostate cancers were subjected to copy number variation analysis with the Affymetrix SNP 6.0 microarray tool. With the investigated cases, tumors obtained from a single prostate exhibited different genetic profiles of variable degrees. Further comparison identified no distinct genetic pattern or signatures specific to multifocal or unifocal prostate cancer. Our findings suggest that samples obtained from multiple sites of a single unifocal prostate cancer show as much genetic heterogeneity and variability as separate tumors obtained from a single multifocal prostate cancer.


Assuntos
Genoma Humano , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Cromossomos Humanos/genética , Análise por Conglomerados , Variações do Número de Cópias de DNA/genética , Genes Neoplásicos , Heterogeneidade Genética , Humanos , Masculino
7.
Opt Express ; 19(3): 1854-9, 2011 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-21369000

RESUMO

Amplification of a gain-switched laser diode is demonstrated in an all-fiber based setup. The amplified spontaneous emission between two consecutive pulses was investigated quantitatively in the time domain. A maximum pulse energy of 13 µJ at a repetition rate of 1 MHz and a pulse duration of 40 ps was extracted, corresponding to a peak power of 270 KW. To the best of our knowledge, this is the highest extracted pulse energy from a laser system seeded by a gain-switched laser diode. Temporal pulse deformation due to intrapulse Raman scattering was observed in the reported system.


Assuntos
Amplificadores Eletrônicos , Tecnologia de Fibra Óptica/instrumentação , Lasers de Estado Sólido , Processamento de Sinais Assistido por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
8.
Comput Aided Surg ; 16(2): 93-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21219118

RESUMO

Survival rates for total shoulder arthroplasty are critically dependent on the correct placement of the glenoid component. Especially in osteoarthritis, pathological version of the glenoid occurs frequently and has to be corrected surgically by eccentric reaming of the glenoid brim. The aim of our study was to evaluate whether eccentric reaming of the glenoid can be achieved more accurately by a novel computer assisted technique. Procedures were conducted on 10 paired human cadaveric specimens presenting glenoids with neutral version. To identify the correction potential of the navigated technique compared to the standard procedure, asymmetric reaming of the glenoid to create a version of -10° was defined as the target. In the navigated group, asymmetric reaming was guided by a 3D fluoroscopic technique. Postoperative 3D scans revealed greater accuracy for the eccentric reaming procedure in the navigated group compared to the freehand group, resulting in glenoid version of -9.8 ± 3.8° and -5.1 ± 4.1°, respectively (p < 0.05). Furthermore, deviation from preoperative planning was significantly reduced in the navigated group. These data indicate that our navigated procedure offers an excellent tool for supporting glenoid replacement in TSA.


Assuntos
Artroplastia de Substituição/métodos , Imageamento Tridimensional/métodos , Articulação do Ombro/cirurgia , Estudos de Viabilidade , Fluoroscopia , Humanos , Articulação do Ombro/diagnóstico por imagem
9.
BMC Med Inform Decis Mak ; 10: 71, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21078179

RESUMO

BACKGROUND: The pathology report of radical prostatectomy specimens plays an important role in clinical decisions and the prognostic evaluation in Prostate Cancer (PCa). The anatomical schema is a helpful tool to document PCa extension for clinical and research purposes. To achieve electronic documentation and analysis, an appropriate documentation model for anatomical schemas is needed. For this purpose we developed cMDX. METHODS: The document architecture of cMDX was designed according to Open Packaging Conventions by separating the whole data into template data and patient data. Analogue custom XML elements were considered to harmonize the graphical representation (e.g. tumour extension) with the textual data (e.g. histological patterns). The graphical documentation was based on the four-layer visualization model that forms the interaction between different custom XML elements. Sensible personal data were encrypted with a 256-bit cryptographic algorithm to avoid misuse. In order to assess the clinical value, we retrospectively analysed the tumour extension in 255 patients after radical prostatectomy. RESULTS: The pathology report with cMDX can represent pathological findings of the prostate in schematic styles. Such reports can be integrated into the hospital information system. "cMDX" documents can be converted into different data formats like text, graphics and PDF. Supplementary tools like cMDX Editor and an analyser tool were implemented. The graphical analysis of 255 prostatectomy specimens showed that PCa were mostly localized in the peripheral zone (Mean: 73% ± 25). 54% of PCa showed a multifocal growth pattern. CONCLUSIONS: cMDX can be used for routine histopathological reporting of radical prostatectomy specimens and provide data for scientific analysis.


Assuntos
Documentação/métodos , Linguagens de Programação , Neoplasias da Próstata/patologia , Algoritmos , Registros Eletrônicos de Saúde , Sistemas de Informação Hospitalar , Humanos , Hipermídia , Masculino , Prostatectomia , Neoplasias da Próstata/diagnóstico , Estudos Retrospectivos
10.
Opt Express ; 18(18): 18981-8, 2010 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-20940792

RESUMO

We investigated of the output characteristics of a spectrally filtered stretched-pulse thulium fiber laser in dependence of cavity dispersion and pump power. The experimental results together with corresponding theoretical modeling allow for a deeper insight into the pulse shaping mechanisms.

11.
Opt Lett ; 35(17): 2991-3, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20808393

RESUMO

We report on chirped-pulse amplification of an ultrafast thulium-doped fiber laser. Pulses with an energy of 3.3 nJ and a bandwidth-limited pulse duration of 195 fs could be amplified to 151 nJ, which corresponds to an average power of 5.7 W at 37.6 MHz pulse repetition rate. The maximum output power was limited by the available pump power. The pulses could be dechirped to a duration of 258 fs.

12.
Dtsch Arztebl Int ; 105(46): 808, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19578445
13.
Lab Invest ; 84(5): 582-7, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15031710

RESUMO

The aim of this study was to assess the frequency of egfr whole gene and CA intron repeat amplification in invasive breast cancer as a mechanism for epidermal growth factor receptor (EGFR) protein overexpression. By means of tissue microarrays, protein overexpression and whole gene amplification were assessed in 222 cases of invasive breast cancer by immunohistochemistry and FISH, respectively. First intron CA repeat amplification was assessed by Taqman RT-PCR. With FISH and RT-PCR, 4.7 and 6.3% of cases showed whole gene and first intron CA repeat amplification, respectively. Amplification dosage varied between two- and four-fold in RT-PCR. By immunohistochemistry, 17.3% showed EGFR overexpression. There was a low correlation between the different methods. In all, 2.9% of cases showed both whole gene amplification and intron CA repeat amplification, and 90.3% of cases were negative for both. Nearly 20% of cases with immunohistochemical protein overexpression showed intron CA repeat amplification, and only 2.2% of cases that were negative on immunohistochemistry showed such amplification. In all, 13% of cases with protein overexpression showed amplification by FISH, and only 1.6% of cases that were negative on immunohistochemistry showed such amplification. Of the cases with EGFR overexpression, 4 (25%) showed either whole gene or intron CA repeat amplification. In conclusion, whole gene amplifications of egfr are rare in invasive breast cancer and explain protein overexpression in only about 12.5% of invasive breast cancer cases. First intron first CA repeat amplification is another important mechanism for EGFR protein overexpression, explaining protein overexpression in about 18.7% of cases. However, since about 75% of cases with EGFR protein overexpression lack either of these amplifications, other expression regulating mechanisms must be considered.


Assuntos
Neoplasias da Mama/genética , Receptores ErbB/genética , Amplificação de Genes , Sequência de Bases , Neoplasias da Mama/patologia , DNA de Neoplasias/genética , Feminino , Dosagem de Genes , Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Invasividade Neoplásica/genética , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase
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