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1.
BMC Oral Health ; 17(1): 32, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27485732

RESUMO

BACKGROUND: The aim of this study was to determine the success of psychotherapeutic treatment for dental phobia by measurement of anxiety using the dental anxiety score (DAS), the state trait anxiety score (STAI state), salivary cortisol and protein concentrations and the salivary secretion rate. Primary endpoint of the study was the comparison of the data before and after psychotherapeutic treatment. METHODS: Forty patients were included into the study. Twenty-four were allocated to the phobic group, 16 to the control group. Saliva was collected upon entering the dental clinic and again after three weeks of psychotherapy. The results were compared with those of a control group. The DAS and STAI questionnaires were completed at each visit. RESULTS: A reduction in DAS values was found after psychotherapy. However, the values remained significantly higher in the phobic group than in the controls. Similar results were found for STAI scores. A slightly higher salivary cortisol level was found in the phobic group. No changes occurred in cortisol or protein concentrations. The salivary secretion rate increased in the phobic patients after psychotherapy. CONCLUSIONS: It could be concluded that psychotherapy is effective in the treatment of dental phobic patients. TRIAL REGISTRATION: This study has been retrospectively registered in the German Clinical Trials Register (# DRKS00009552 ) on 10/19/15.


Assuntos
Ansiedade ao Tratamento Odontológico/terapia , Psicoterapia , Ansiedade , Humanos , Hidrocortisona/análise , Saliva/química , Inquéritos e Questionários
2.
Spine (Phila Pa 1976) ; 39(25): E1503-9, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25417826

RESUMO

STUDY DESIGN: In vivo analysis in an ovine model. OBJECTIVE: To evaluate the feasibility of radiopaque ultrahigh molecular weight polyethylene (UHMWPE) sublaminar wires in a growth-guidance spinal system by assessing stability, biocompatibility, and growth potential. SUMMARY OF BACKGROUND DATA: Several growth-guidance systems have been developed for the treatment of early-onset scoliosis. The use of gliding pedicle screws and metal sublaminar wires during these procedures can cause metal-on-metal debris formation and neurological deficits. Novel radiopaque UHMWPE wires are introduced to safely facilitate longitudinal growth and provide stability in a growth-guidance system for early-onset scoliosis. METHODS: Twelve immature sheep received posterior segmental spinal instrumentation; pedicle screws were inserted at L5 and radiopaque UHMWPE (bismuth trioxide) wires were passed sublaminarly at each level between L3 and T12 and fixed to dual cobalt-chromium rods. Four age-matched animals that were not operated were evaluated to serve as a control group. Radiographs were obtained to measure growth of the instrumented segment. After 24 weeks, the animals were killed and the spines were harvested for histological evaluation and high-resolution peripheral quantitative computed tomographic analysis. RESULTS: No neurological deficits occurred and all instrumentation remained stable. One animal died from an unknown cause. Substantial growth occurred in the instrumented segments (L5-T11) in the intervention group (27 ± 2 mm), which was not significantly different to the control group, (30 ± 4 mm, P = 0.42). High-resolution peripheral quantitative computed tomographic analysis clearly showed safe routing and fixation of the UHMWPE wires and instrumentation. Despite the noted growth, ectopic bone formation with the formation of bony bridges was observed in all animals. Histology revealed no evidence of chronic inflammation or wear debris. CONCLUSION: This study shows the first results of radiopaque UHMWPE sublaminar wires as part of a growth-guidance spinal system. UHMWPE sublaminar wires facilitated near-normal longitudinal spinal growth. All instrumentation remained stable throughout follow-up; no wire breakage or loosening occurred and no adverse local-tissue response to these wires was observed. LEVEL OF EVIDENCE: N/A.


Assuntos
Fios Ortopédicos , Meios de Contraste/química , Polietilenos/química , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Animais , Modelos Animais de Doenças , Estudos de Viabilidade , Imageamento Tridimensional , Ovinos , Tomografia Computadorizada por Raios X
4.
Am J Transplant ; 11(1): 156-62, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21199355

RESUMO

In January 2005, an 18-year-old male patient with acute myeloid leukemia (AML) received a haploidentical hematopoietic stem cell transplantation (HSCT) from his father. He developed hemolytic uremic syndrome and end-stage renal disease (ESRD) requiring hemodialysis on day 357 after HSCT. On day 1020 after HSCT, a living kidney donation from the stem cell donor was carried out. The creatinine before kidney transplantation (KT) was ≈450 µmol/L, 268 µmol/L on day 2 after KT, 88 µM on day 38 and 89 µmol/L on day 960 (day 1980 after HSCT). Immunosuppression was gradually discontinued: cortisone on day 28, tacrolimus on day 32 and MMF on day 100 after KT (day 1120 after HSCT). As of June 2010, 66 months after HSCT and 32 months after KT, the patient has had neither rejection episodes nor clinical manifestations of transplantation-related complications. The patient reached 100% hematopoietic donor chimerism prekidney transplant and retained this state postkidney transplant. This unique case is the first report of a successful kidney transplant without immunosuppression after HSCT from the same haploidentical donor.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Falência Renal Crônica/cirurgia , Transplante de Rim , Doadores Vivos , Adolescente , Adulto , Humanos , Terapia de Imunossupressão , Falência Renal Crônica/induzido quimicamente , Leucemia Mieloide Aguda/terapia , Masculino , Quimeras de Transplante
5.
J Appl Microbiol ; 109(4): 1150-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20456528

RESUMO

AIMS: We established a real-time PCR assay for the detection and strain identification of Candida species and demonstrated the ability to differentiate between Candida albicans the most common species, and also Candida parapsilosis, Candida glabrata, Candida tropicalis and Candida dubliniensis by LightCycler PCR and melting curve analysis. METHODS AND RESULTS: The DNA isolation from cultures and serum was established using the QIAmp Tissue Kit. The sensitivity of the assay was ≥ 2 genome equivalents/assay. It was possible to differentiate all investigated Candida species by melting curve analysis, and no cross-reaction to human DNA or Aspergillus species could be observed. CONCLUSIONS: The established real-time PCR assay is a useful tool for the rapid identification of Candida species and a base technology for more complex PCR assays. SIGNIFICANCE AND IMPACT OF THE STUDY: We carried out initial steps in validation of a PCR assay for the detection and differentiation of medically relevant Candida species. The PCR was improved by generating PCR standards, additional generation of melting curves for species identification and the possibility to investigate different specimens simultaneously.


Assuntos
Candida/classificação , Reação em Cadeia da Polimerase/métodos , Candida/genética , Candida/isolamento & purificação , Candida albicans/genética , Candida albicans/isolamento & purificação , Candida glabrata/genética , Candida glabrata/isolamento & purificação , Candida tropicalis/genética , Candida tropicalis/isolamento & purificação , DNA Fúngico/isolamento & purificação , Humanos
6.
Nature ; 460(7252): 213-9, 2009 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-19587763

RESUMO

Virtually all massive galaxies, including our own, host central black holes ranging in mass from millions to billions of solar masses. The growth of these black holes releases vast amounts of energy that powers quasars and other weaker active galactic nuclei. A tiny fraction of this energy, if absorbed by the host galaxy, could halt star formation by heating and ejecting ambient gas. A central question in galaxy evolution is the degree to which this process has caused the decline of star formation in large elliptical galaxies, which typically have little cold gas and few young stars, unlike spiral galaxies.

7.
Transplant Proc ; 39(10): 3101-4, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18089331

RESUMO

Dendritic cells (DCs) play a key role in transplantation tolerance and immune reactions to transplants. In order to ascertain whether DC levels are predictive for rejection, we examined the levels and expression patterns of DCs of renal transplant patients following immunosuppressive and/or surgical interventions. Myeloid (HLA-DR+/CD11c+) and plasmacytoid (HLA-DR+/CD123+) DCs were characterized by flow cytometry over 28 days. We demonstrated that myeloid DCs and plasmacytoid DCs in peripheral blood were discernable and dramatically decreased following renal transplantation and immunosuppression. Furthermore, the expression of CD62L was significantly up-regulated (P=.032), while CD86 was significantly down-regulated (P=.008) on myeloid but not plasmacytoid DCs. Although DC levels alone were not predictive for the occurrence of a rejection episode, in combination with other factors they may be indicative of rejection, thereby sparing the patient a biopsy.


Assuntos
Células Dendríticas/classificação , Transplante de Rim/imunologia , Antígenos CD/análise , Antígeno CD11c/análise , Células Dendríticas/imunologia , Rejeição de Enxerto/imunologia , Antígenos HLA-DR/análise , Humanos , Subunidade alfa de Receptor de Interleucina-3/análise , Valor Preditivo dos Testes , Receptores de Interleucina-3/análise , Valores de Referência
8.
Scand J Immunol ; 64(5): 544-53, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17032248

RESUMO

Joint destruction in rheumatoid arthritis (RA) starts typically at sites of mechanically stressed inserts of the synovial membrane near the cartilage/bone border. In the therapy of RA, tumour necrosis factor (TNF) antagonists have rapidly emerged as a valuable class of anti-rheumatic agents that reduce joint destruction. The aim of this study was to investigate and profile genes involved in the interaction between articular movement and anti-TNF therapy in an in vitro model. Murine LS48 cells, an established substitute for invasive RA synovial fibroblasts, were cultured, stretched and/or treated with anti-TNF-alpha antibody for 24 h. RNA was isolated and gene transcript levels were determined using U74Av2 Affymetrix GeneChips to identify transcriptional events. Positive findings were verified by polymerase chain reaction (PCR). We identified 170 differentially regulated genes, including 44 of particular interest. Gene expression fell into different functional groups that can be explained by RA pathogenesis and experimental conditions. For 21 genes of the 44 of particular interest, regulation could be confirmed by real-time PCR. Remarkably, we found structural as well as functional genes differently regulated between stretched cells, anti-TNF-treated cells, and stretched cells treated with anti-TNF antibody. Additionally, we also found a large number of genes that are apparently not related to the experimental conditions. Mechanical exertion modulates gene expression and subsequently cellular response to anti-TNF therapy. Results in exerted cells correspond to current knowledge regarding RA pathogenesis and underline the relevance of our experimental approach. Finally, the central function of the interleukin-18 system in joint destruction could be confirmed by our findings.


Assuntos
Anticorpos/farmacologia , Artrite Experimental/imunologia , Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica , Fator de Necrose Tumoral alfa/imunologia , Animais , Artrite Experimental/metabolismo , Linhagem Celular , Frequência do Gene , Camundongos , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Mecânico
9.
J Cancer Res Clin Oncol ; 131(4): 226-8, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15599594

RESUMO

PURPOSE: Primary endometrial squamous cell carcinoma (ESCC) are rare but aggressive malignancies. To evaluate therapeutically relevant molecules, ESCC were investigated immunohistochemically. MATERIAL AND METHODS: Eight ESCC were stained with antibodies against estrogen and progesterone receptors, HER-2/neu, and COX-2 followed by semiquantitative evaluation of the staining results. RESULTS: Seven out of eight ESCC were negative for estrogen receptor as well as for HER-2/neu. Four tumors showed positivity for progesterone receptor. All ESCC displayed COX-2 overexpression. CONCLUSIONS: Primary ESCC are probably not under hormonal control of estrogens and lack HER-2/neu expression. Thus, anti-hormonal or antibody therapy with herceptine is not indicated. The use of COX-2 inhibitors might be a therapeutic alternative in ESCC that requires further investigation.


Assuntos
Carcinoma de Células Escamosas/química , Neoplasias do Endométrio/química , Prostaglandina-Endoperóxido Sintases/análise , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Ciclo-Oxigenase 2 , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Proteínas de Membrana , Pessoa de Meia-Idade , Regulação para Cima
10.
Osteoarthritis Cartilage ; 10(12): 914-21, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12464551

RESUMO

OBJECTIVE: To test the hypotheses that absolute side differences in knee joint cartilage morphology are substantially smaller than intersubject variability, and that systematic side differences are determined by (force) dominance of the lower limbs. METHODS: Fifteen healthy volunteers with definite dominance of one lower limb were studied. Knees were imaged sagittally with a validated, high-resolution MR sequence. Transverse MR images of the thigh and calf were acquired with a spin echo sequence. Knee joint cartilage volume, thickness and joint surface areas, as well as muscle cross sectional areas were determined with in house post-processing software. RESULTS: Absolute side differences amounted to 5.0+/-3.7% for the knee cartilage volume, 3.8+/-3.1% for cartilage thickness, and 3.4+/-1.7% for joint surface areas. The intersubject variability was 24.8%, 14.4%, and 14.1%, respectively. Volunteers with dominance of one of both lower limbs did not display significant side differences in cartilage morphology, but the side differences of the thigh musculature correlated positively with side differences of knee joint cartilage volume (r=+0.68; P< 0.01). CONCLUSIONS: The results advocate the use of cartilage parameters from the contra-lateral limb for retrospectively estimating cartilage loss in patients with unilateral osteoarthritis (OA), and for determining local risk factors of OA in cross-sectional epidemiological studies, which are specific to pre-morbid cartilage morphology. Functional (force) dominance of one of both lower limbs does not explain side differences of articular cartilage morphology, but side differences are positively associated with side differences in muscle cross sectional areas.


Assuntos
Cartilagem Articular/anatomia & histologia , Lateralidade Funcional/fisiologia , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Pessoa de Meia-Idade , Músculos/anatomia & histologia , Patela/anatomia & histologia , Tíbia/anatomia & histologia
11.
Osteoarthritis Cartilage ; 10(12): 922-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12464552

RESUMO

OBJECTIVE: Follow up of osteoarthritis (OA) and evaluation of structure modifying OA drugs require longitudinal data on cartilage structure. The aim of this study was to analyse the long term and resegmentation precision of quantitative cartilage analysis with magnetic resonance imaging (qMRI) in vivo, and to relate precision errors to the estimated cartilage loss in OA. METHOD: Sagittal MR images of the knee were obtained in 14 individuals, four datasets being acquired in a first imaging session. In 12 subjects, two further datasets were acquired over the next months. Image analysis was performed in the same session for image data obtained under short-term and long-term imaging conditions, and in three different sessions (months apart) for the first data set (resegmentation precision). RESULTS: Long-term precision errors ranged from 1.4% (total knee) to 3.9% (total femur) for cartilage volume and thickness and were only marginally higher than those under short term conditions. In the medial tibia, the error was 84 mm(3) compared with an estimated loss of >1,200 mm(3) in varus OA. Precision errors for resegmentation were somewhat higher, but considerably smaller than the intersubject variability. CONCLUSIONS: Scanner drift and changes in imaging or patient conditions appear not to represent a critical problem in quantitative cartilage analysis with magnetic resonance imaging (qMRI). In longitudinal studies, image analysis of sequential data should be performed within the same post-processing session. Under these conditions, qMRI promises to be a very powerful method to assess structural change of cartilage in OA.


Assuntos
Cartilagem Articular/anatomia & histologia , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Fêmur/anatomia & histologia , Humanos , Masculino , Tíbia/anatomia & histologia
12.
Osteoarthritis Cartilage ; 10(1): 44-50, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11795982

RESUMO

OBJECTIVE: This study tests the hypothesis that functional adaptation occurs in human joints, and that substantial differences in joint 'loading history' explain the phenotypic variability observed in human cartilage morphology. METHOD: We examined 18 triathletes (nine men and nine women) who had been physically active throughout life (training for >10 h per week for the last 3 years), and 18 volunteers that had never been physically active on a regular basis. The right knee joints were imaged with a previously validated fat-suppressed gradient-echo MR sequence. Cartilage volume, thickness, joint surface areas, and normalized cartilage signal intensity were determined with post-processing software, specifically designed for these applications. RESULTS: The knee joint cartilage thickness, and signal intensity were not significantly different between athletes and inactive volunteers, but male athletes displayed significantly larger knee joint surfaces (P< 0.01; +8.8%). Female athletes displayed a significantly larger medial tibia (P< 0.05; +18.9%), the difference in the total knee surface area reaching borderline significance (P=0.08; +7.0%). CONCLUSIONS: The results suggest that joint size can be modulated during growth, but that (opposite to muscle and bone) the thickness of the cartilage does not adapt to mechanical stimulation. This finding may reveal a general principle in the development and functional adaptation of diarthrodial joints, elucidating an important mechanism for reducing mechanical stress in biphasic cartilage layers.


Assuntos
Adaptação Fisiológica , Articulação do Joelho/fisiologia , Esportes/fisiologia , Adulto , Fenômenos Biomecânicos , Cartilagem Articular/anatomia & histologia , Cartilagem Articular/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Masculino , Caracteres Sexuais , Estatísticas não Paramétricas , Suporte de Carga
13.
Development ; 128(22): 4415-24, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11714668

RESUMO

The Pax6 gene has a central role in development of the eye. We show, through targeted deletion in the mouse, that an ectoderm enhancer in the Pax6 gene is required for normal lens formation. Ectoderm enhancer-deficient embryos exhibit distinctive defects at every stage of lens development. These include a thinner lens placode, reduced placodal cell proliferation, and a small lens pit and lens vesicle. In addition, the lens vesicle fails to separate from the surface ectoderm and the maturing lens is smaller and shows a delay in fiber cell differentiation. Interestingly, deletion of the ectoderm enhancer does not eliminate Pax6 production in the lens placode but results in a diminished level that, in central sections, is apparent primarily on the nasal side. This argues that Pax6 expression in the lens placode is controlled by the ectoderm enhancer and at least one other transcriptional control element. It also suggests that Pax6 enhancers active in the lens placode drive expression in distinct subdomains, an assertion that is supported by the expression pattern of a lacZ reporter transgene driven by the ectoderm enhancer. Interestingly, deletion of the ectoderm enhancer causes loss of expression of Foxe3, a transcription factor gene mutated in the dysgenetic lens mouse. When combined, these data and previously published work allow us to assemble a more complete genetic pathway describing lens induction. This pathway features (1) a pre-placodal phase of Pax6 expression that is required for the activity of multiple, downstream Pax6 enhancers; (2) a later, placodal phase of Pax6 expression regulated by multiple enhancers; and (3) the Foxe3 gene in a downstream position. This pathway forms a basis for future analysis of lens induction mechanism.


Assuntos
Ectoderma/citologia , Indução Embrionária , Elementos Facilitadores Genéticos , Proteínas de Homeodomínio/genética , Cristalino/embriologia , Animais , Diferenciação Celular , Proteínas do Olho , Fatores de Transcrição Forkhead , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Cristalino/anormalidades , Cristalino/citologia , Camundongos , Camundongos Mutantes , Modelos Biológicos , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados , Proteínas Repressoras , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Development ; 128(22): 4425-38, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11714669

RESUMO

We describe experiments showing that fibroblast growth factor receptor (Fgfr) signaling plays a role in lens induction. Three distinct experimental strategies were used: (1) using small-molecule inhibitors of Fgfr kinase activity, we showed that both the transcription level and protein expression of Pax6, a transcription factor critical for lens development, was diminished in the presumptive lens ectoderm; (2) transgenic mice (designated Tfr7) that expressed a dominant-negative Fgf receptor exclusively in the presumptive lens ectoderm showed defects in formation of the lens placode at E9.5 but in addition, showed reduced levels of expression for Pax6, Sox2 and Foxe3, all markers of lens induction; (3) by performing crosses between Tfr7 transgenic and Bmp7-null mice, we showed that there is a genetic interaction between Fgfr and Bmp7 signaling at the induction phases of lens development. This manifested as exacerbated lens development defects and lower levels of Pax6 and Foxe3 expression in Tfr7/Tfr7, Bmp7(+/-) mice when compared with Tfr7/Tfr7 mice alone. As Bmp7 is an established lens induction signal, this provides further evidence that Fgfr activity is important for lens induction. This analysis establishes a role for Fgfr signaling in lens induction and defines a genetic pathway in which Fgfr and Bmp7 signaling converge on Pax6 expression in the lens placode with the Foxe3 and Sox2 genes lying downstream.


Assuntos
Indução Embrionária , Cristalino/embriologia , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Fator de Crescimento Transformador beta , Animais , Antígenos de Diferenciação , Proteína Morfogenética Óssea 7 , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Divisão Celular , Cruzamentos Genéticos , Proteínas de Ligação a DNA/biossíntese , Epitélio , Proteínas do Olho , Fatores de Transcrição Forkhead , Genes Reporter , Proteínas HMGB , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Transgênicos , Modelos Genéticos , Proteínas Nucleares/biossíntese , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Receptores de Fatores de Crescimento de Fibroblastos/genética , Proteínas Repressoras , Fatores de Transcrição SOXB1 , Transdução de Sinais , Fatores de Transcrição/metabolismo
15.
Skeletal Radiol ; 30(3): 144-50, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11357452

RESUMO

OBJECTIVE: To compare the cartilage thickness, volume, and articular surface areas of the knee joint between young healthy, non-athletic female and male individuals. SUBJECTS AND DESIGN: MR imaging was performed in 18 healthy subjects without local or systemic joint disease (9 female, age 22.3 +/- 2.4 years, and 9 male, age 22.2 +/- 1.9 years.), using a fat-suppressed FLASH 3D pulse sequence (TR = 41 ms, TE = 11 ms, FA = 30 degrees) with sagittal orientation and a spatial resolution of 2 x 0.31 x 0.31 mm3. After three-dimensional reconstruction and triangulation of the knee joint cartilage plates, the cartilage thickness (mean and maximal), volume, and size of the articular surface area were quantified, independent of the original section orientation. RESULTS AND CONCLUSIONS: Women displayed smaller cartilage volumes than men, the percentage difference ranging from 19.9% in the patella, to 46.6% in the medial tibia. The gender differences of the cartilage thickness were smaller, ranging from 2.0% in the femoral trochlea to 13.3% in the medial tibia for the mean thickness, and from 4.3% in the medial femoral condyle to 18.3% in the medial tibia for the maximal cartilage thickness. The differences between the cartilage surface areas were similar to those of the volumes, with values ranging from 21.0% in the femur to 33.4% in the lateral tibia. Gender differences could be reduced for cartilage volume and surface area when normalized to body weight and body weight x body height. The study demonstrates significant gender differences in cartilage volume and surface area of men and women, which need to be taken into account when retrospectively estimating articular cartilage loss in patients with symptoms of degenerative joint disease. Differences in cartilage volume are primarily due to differences in joint surface areas (epiphyseal bone size), not to differences in cartilage thickness.


Assuntos
Cartilagem Articular/anatomia & histologia , Imageamento Tridimensional , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética , Caracteres Sexuais , Adulto , Feminino , Humanos , Masculino , Valores de Referência
16.
Magn Reson Imaging ; 19(2): 177-85, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11358655

RESUMO

In view of follow up, survey and development of therapeutic strategies for osteoarthritis where cartilage deterioration plays an important role, a non invasive, reliable and quantitative assessment of the articular cartilage is desirable. The currently available high resolution T(1)-weighted (T1-w) 3D FLASH pulse sequences with frequency selective fat suppression are very time consuming. We have 1) optimized a high resolution T1-w 3D FLASH water excitation (WE) sequence for short acquisition time and cartilage visualization, and 2) validated this sequence for cartilage volume and thickness quantification. The spectral fat presaturation was replaced by selective water excitation. The flip angle of the WE sequence was optimized for the contrast to noise (C/N(cart)) ratio of cartilage. Sagittal datasets (voxel size: 0.31 x 0.31 x 2 mm(3)) of the knees of nine healthy volunteers were acquired both, with the 3D FLASH WE (17.2/6.6/30 degrees ) sequence (WE) and a previously validated 3D FLASH fat saturated (42/11/30 degrees ) sequence (FS). For validation of the WE sequence, cartilage volume, mean and maximal cartilage thickness of the two sequences were compared. Reproducibility was assessed by calculating the coefficient of variation (COV %) of 4 consecutive WE data sets in the volunteers. The acquisition time was reduced from 16'30" (FS) down to 7'14" for the WE sequence. Image contrast and visualization of the cartilage was very similar, but delineation of the basal layer of the cartilage was slightly improved with the WE sequence. A flip angle of 30 degrees provided the best C/N(cart) ratios (WE). Reproducibility (COV) was between 1.9 and 5.9%. Cartilage volume and thickness agreed within 4% between FS and WE sequence. The WE sequence allows for rapid, valid and reproducible quantification of articular cartilage volume and thickness, prerequisites for follow-up examinations. The reduced acquisition time (50% of FS) enables routine clinical application and thus may contribute to a broader assessment of osteoarthritis.


Assuntos
Cartilagem Articular/patologia , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Adulto , Idoso , Feminino , Análise de Fourier , Humanos , Articulação do Joelho/patologia , Masculino , Pessoa de Meia-Idade , Análise Numérica Assistida por Computador , Osteoartrite do Joelho/diagnóstico , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/cirurgia , Reprodutibilidade dos Testes
17.
Mech Dev ; 101(1-2): 167-74, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231069

RESUMO

Insulin-like growth factor-I (IGF-I) has been implicated as a regulator of lens development. Experiments performed in the chick have indicated that IGF-I can stimulate lens fiber cell differentiation and may be involved in controlling lens polarization. To assess IGF-I activity on mammalian lens cells in vivo, we generated transgenic mice in which this factor was overexpressed from the alphaA-crystallin promoter. Interestingly, we observed no premature differentiation of lens epithelial cells. The pattern of lens polarization was perturbed, with an apparent expansion of the epithelial compartment towards the posterior lens pole. The distribution of immunoreactivity for MIP26 and p57(KIP2) and a modified pattern of proliferation suggested that this morphological change was best described as an expansion of the germinative and transitional zones. The expression of IGF-I signaling components in the normal transitional zone and expansion of the transitional zone in the transgenic lens both suggest that endogenous IGF-I may provide a spatial cue that helps to control the normal location of this domain.


Assuntos
Fator de Crescimento Insulin-Like I/biossíntese , Cristalino/embriologia , Cristalino/metabolismo , Animais , Catarata/genética , Diferenciação Celular , Divisão Celular , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência , Modelos Genéticos , Fenótipo , Regiões Promotoras Genéticas , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , Transdução de Sinais , Transgenes
18.
Ann N Y Acad Sci ; 950: 39-53, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11797762

RESUMO

In the year 1900, humanity had barely a notion of our place on the cosmic stage, and no inkling at all of how we got here. The one hundred short years of the twentieth century sufficed to unravel 14 billion years of cosmic history and how those grand events, after 9 billions of years or so, set the stage for the birth of our own home, the Solar System. The key events in this history are not hard to comprehend; they can be sketched in a few brief pages. This precious knowledge is part of our shared heritage as human beings and is fundamental to the future prospects of our species. Without it, we are ignorant of the powerful forces that have shaped our past and that will shape our destiny in the future. Read here the cosmic history of humanity, beginning with the Big Bang.


Assuntos
Meio Ambiente Extraterreno , Física , Humanos , Fenômenos Físicos
19.
Osteoarthritis Cartilage ; 8(6): 426-33, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11069727

RESUMO

OBJECTIVE: To develop an MR-based method for the in vivo evaluation of the structural composition of articular cartilage. DESIGN: Five sagittal magnetic resonance imaging (MRI) protocols were acquired throughout the knee joint of 15 healthy volunteers and the boundaries of the cartilage segmented from a previously validated sequence with high contrast between cartilage and surrounding tissue. The other sequences were matched to these data, using a 3D least-squares fit algorithm to exclude motion artefacts. In this way secondary images were computed that included information about the proton density (interstitial water content) and the magnetization transfer coefficient (macromolecules, collagen). The average signal intensities of the 3D cartilage plates were extracted from these data sets and related to a phantom. RESULTS: The signal intensity data showed a high interindividual variability for the proton density (patella 31%, lateral tibia 36%, medial tibia 29%); the patella displaying higher values than the tibia (P< 0.001). There were high correlations between the three plates. The magnetization transfer coefficient also showed high variability (patella 25%, lateral tibia 32%, medial tibia 30%) with the lowest values in the medial tibia (P< 0.01) and lower correlations between the plates. The slice-to-slice variation (medial to lateral) ranged from 9% to 24%. CONCLUSION: An MR-based method has been developed for evaluating the proton density and magnetization transfer of articular cartilage in vivo and observing systematic differences between knee joint cartilage plates. The technique has the potential to supply information about the water content and collagen of articular cartilage, in particular at the early state of osteoarthritic degeneration.


Assuntos
Cartilagem Articular/anatomia & histologia , Articulação do Joelho/anatomia & histologia , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Patela/anatomia & histologia , Imagens de Fantasmas , Tíbia/anatomia & histologia
20.
Development ; 127(12): 2563-72, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10821755

RESUMO

We investigated the mechanism of tissue induction and specification using the lacrimal gland as a model system. This structure begins its morphogenesis as a bud-like outgrowth of the conjunctival epithelium and ultimately forms a branched structure with secretory function. Using a reporter transgene as a specific marker for gland epithelium, we show that the transcription factor Pax6 is required for normal development of the gland and is probably an important competence factor. In investigating the cell-cell signaling required, we show that fibroblast growth factor (FGF) 10 is sufficient to stimulate ectopic lacrimal bud formation in ocular explants. Expression of FGF10 in the mesenchyme adjacent to the presumptive lacrimal bud and absence of lacrimal gland development in FGF10-null mice strongly suggest that it is an endogenous inducer. This was supported by the observation that inhibition of signaling by a receptor for FGF10 (receptor 2 IIIb) suppressed development of the endogenous lacrimal bud. In explants of mesenchyme-free gland epithelium, FGF10 stimulated growth but not branching morphogenesis. This suggested that its role in induction is to stimulate proliferation and, in turn, that FGF10 combines with other factors to provide the instructive signals required for lacrimal gland development.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Fatores de Crescimento de Fibroblastos/fisiologia , Proteínas de Homeodomínio , Aparelho Lacrimal/embriologia , Animais , Epitélio/embriologia , Proteínas do Olho/fisiologia , Fator 10 de Crescimento de Fibroblastos , Fator 2 de Crescimento de Fibroblastos/fisiologia , Fator 7 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/deficiência , Fatores de Crescimento de Fibroblastos/genética , Substâncias de Crescimento/fisiologia , Mesoderma/citologia , Mesoderma/fisiologia , Camundongos , Camundongos Knockout , Morfogênese , Técnicas de Cultura de Órgãos , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados , Proteínas Repressoras , Transdução de Sinais
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