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1.
BMC Oral Health ; 17(1): 32, 2016 Aug 02.
Article in English | MEDLINE | ID: mdl-27485732

ABSTRACT

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.


Subject(s)
Dental Anxiety/therapy , Psychotherapy , Anxiety , Humans , Hydrocortisone/analysis , Saliva/chemistry , Surveys and Questionnaires
2.
Spine (Phila Pa 1976) ; 39(25): E1503-9, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-25417826

ABSTRACT

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.


Subject(s)
Bone Wires , Contrast Media/chemistry , Polyethylenes/chemistry , Scoliosis/diagnostic imaging , Scoliosis/surgery , Animals , Disease Models, Animal , Feasibility Studies , Imaging, Three-Dimensional , Sheep , Tomography, X-Ray Computed
4.
Am J Transplant ; 11(1): 156-62, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21199355

ABSTRACT

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.


Subject(s)
Hematopoietic Stem Cell Transplantation , Kidney Failure, Chronic/surgery , Kidney Transplantation , Living Donors , Adolescent , Adult , Humans , Immunosuppression Therapy , Kidney Failure, Chronic/chemically induced , Leukemia, Myeloid, Acute/therapy , Male , Transplantation Chimera
5.
J Appl Microbiol ; 109(4): 1150-8, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20456528

ABSTRACT

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.


Subject(s)
Candida/classification , Polymerase Chain Reaction/methods , Candida/genetics , Candida/isolation & purification , Candida albicans/genetics , Candida albicans/isolation & purification , Candida glabrata/genetics , Candida glabrata/isolation & purification , Candida tropicalis/genetics , Candida tropicalis/isolation & purification , DNA, Fungal/isolation & purification , Humans
6.
Nature ; 460(7252): 213-9, 2009 Jul 09.
Article in English | MEDLINE | ID: mdl-19587763

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-18089331

ABSTRACT

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.


Subject(s)
Dendritic Cells/classification , Kidney Transplantation/immunology , Antigens, CD/analysis , CD11c Antigen/analysis , Dendritic Cells/immunology , Graft Rejection/immunology , HLA-DR Antigens/analysis , Humans , Interleukin-3 Receptor alpha Subunit/analysis , Predictive Value of Tests , Receptors, Interleukin-3/analysis , Reference Values
8.
Scand J Immunol ; 64(5): 544-53, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17032248

ABSTRACT

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.


Subject(s)
Antibodies/pharmacology , Arthritis, Experimental/immunology , Fibroblasts/drug effects , Gene Expression Regulation , Tumor Necrosis Factor-alpha/immunology , Animals , Arthritis, Experimental/metabolism , Cell Line , Gene Frequency , Mice , Models, Biological , Oligonucleotide Array Sequence Analysis , Stress, Mechanical
9.
J Cancer Res Clin Oncol ; 131(4): 226-8, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15599594

ABSTRACT

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.


Subject(s)
Carcinoma, Squamous Cell/chemistry , Endometrial Neoplasms/chemistry , Prostaglandin-Endoperoxide Synthases/analysis , Receptor, ErbB-2/analysis , Receptors, Estrogen/analysis , Receptors, Progesterone/analysis , Adult , Aged , Aged, 80 and over , Cyclooxygenase 2 , Female , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Membrane Proteins , Middle Aged , Up-Regulation
10.
Osteoarthritis Cartilage ; 10(12): 914-21, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12464551

ABSTRACT

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.


Subject(s)
Cartilage, Articular/anatomy & histology , Functional Laterality/physiology , Knee Joint/anatomy & histology , Magnetic Resonance Imaging/methods , Adult , Female , Humans , Leg/physiology , Male , Middle Aged , Muscles/anatomy & histology , Patella/anatomy & histology , Tibia/anatomy & histology
11.
Osteoarthritis Cartilage ; 10(12): 922-8, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12464552

ABSTRACT

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.


Subject(s)
Cartilage, Articular/anatomy & histology , Knee Joint/anatomy & histology , Magnetic Resonance Imaging/methods , Adult , Female , Femur/anatomy & histology , Humans , Male , Tibia/anatomy & histology
12.
Osteoarthritis Cartilage ; 10(1): 44-50, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11795982

ABSTRACT

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.


Subject(s)
Adaptation, Physiological , Knee Joint/physiology , Sports/physiology , Adult , Biomechanical Phenomena , Cartilage, Articular/anatomy & histology , Cartilage, Articular/physiology , Female , Humans , Image Processing, Computer-Assisted/methods , Knee Joint/anatomy & histology , Magnetic Resonance Imaging/methods , Male , Sex Characteristics , Statistics, Nonparametric , Weight-Bearing
13.
Development ; 128(22): 4415-24, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11714668

ABSTRACT

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.


Subject(s)
Ectoderm/cytology , Embryonic Induction , Enhancer Elements, Genetic , Homeodomain Proteins/genetics , Lens, Crystalline/embryology , Animals , Cell Differentiation , Eye Proteins , Forkhead Transcription Factors , Gene Expression Regulation, Developmental , Homeodomain Proteins/metabolism , Lens, Crystalline/abnormalities , Lens, Crystalline/cytology , Mice , Mice, Mutant Strains , Models, Biological , PAX6 Transcription Factor , Paired Box Transcription Factors , Repressor Proteins , Transcription Factors/genetics , Transcription Factors/metabolism
14.
Development ; 128(22): 4425-38, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11714669

ABSTRACT

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.


Subject(s)
Embryonic Induction , Lens, Crystalline/embryology , Receptors, Fibroblast Growth Factor/metabolism , Transforming Growth Factor beta , Animals , Antigens, Differentiation , Bone Morphogenetic Protein 7 , Bone Morphogenetic Proteins/genetics , Bone Morphogenetic Proteins/metabolism , Cell Division , Crosses, Genetic , DNA-Binding Proteins/biosynthesis , Epithelium , Eye Proteins , Forkhead Transcription Factors , Genes, Reporter , HMGB Proteins , Homeodomain Proteins/biosynthesis , Homeodomain Proteins/genetics , Mice , Mice, Transgenic , Models, Genetic , Nuclear Proteins/biosynthesis , PAX6 Transcription Factor , Paired Box Transcription Factors , Peptide Fragments/genetics , Peptide Fragments/metabolism , Receptors, Fibroblast Growth Factor/antagonists & inhibitors , Receptors, Fibroblast Growth Factor/genetics , Repressor Proteins , SOXB1 Transcription Factors , Signal Transduction , Transcription Factors/metabolism
15.
Magn Reson Imaging ; 19(2): 177-85, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11358655

ABSTRACT

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.


Subject(s)
Cartilage, Articular/pathology , Image Enhancement , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Adult , Aged , Female , Fourier Analysis , Humans , Knee Joint/pathology , Male , Middle Aged , Numerical Analysis, Computer-Assisted , Osteoarthritis, Knee/diagnosis , Osteoarthritis, Knee/pathology , Osteoarthritis, Knee/surgery , Reproducibility of Results
16.
Skeletal Radiol ; 30(3): 144-50, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11357452

ABSTRACT

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.


Subject(s)
Cartilage, Articular/anatomy & histology , Imaging, Three-Dimensional , Knee Joint/anatomy & histology , Magnetic Resonance Imaging , Sex Characteristics , Adult , Female , Humans , Male , Reference Values
17.
Mech Dev ; 101(1-2): 167-74, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11231069

ABSTRACT

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.


Subject(s)
Insulin-Like Growth Factor I/biosynthesis , Lens, Crystalline/embryology , Lens, Crystalline/metabolism , Animals , Cataract/genetics , Cell Differentiation , Cell Division , Immunohistochemistry , In Situ Hybridization , Mice , Mice, Transgenic , Microscopy, Fluorescence , Models, Genetic , Phenotype , Promoter Regions, Genetic , Protein Structure, Tertiary , RNA, Messenger/metabolism , Signal Transduction , Transgenes
18.
Ann N Y Acad Sci ; 950: 39-53, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11797762

ABSTRACT

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.


Subject(s)
Extraterrestrial Environment , Physics , Humans , Physical Phenomena
19.
Osteoarthritis Cartilage ; 8(6): 426-33, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11069727

ABSTRACT

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.


Subject(s)
Cartilage, Articular/anatomy & histology , Knee Joint/anatomy & histology , Adult , Female , Humans , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Male , Patella/anatomy & histology , Phantoms, Imaging , Tibia/anatomy & histology
20.
Development ; 127(12): 2563-72, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10821755

ABSTRACT

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.


Subject(s)
DNA-Binding Proteins/physiology , Fibroblast Growth Factors/physiology , Homeodomain Proteins , Lacrimal Apparatus/embryology , Animals , Epithelium/embryology , Eye Proteins/physiology , Fibroblast Growth Factor 10 , Fibroblast Growth Factor 2/physiology , Fibroblast Growth Factor 7 , Fibroblast Growth Factors/deficiency , Fibroblast Growth Factors/genetics , Growth Substances/physiology , Mesoderm/cytology , Mesoderm/physiology , Mice , Mice, Knockout , Morphogenesis , Organ Culture Techniques , PAX6 Transcription Factor , Paired Box Transcription Factors , Repressor Proteins , Signal Transduction
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