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1.
Ophthalmologie ; 120(7): 726-733, 2023 Jul.
Article in German | MEDLINE | ID: mdl-36729123

ABSTRACT

OBJECTIVE: The need for care in ophthalmology is constantly increasing due to demographic changes. The study analyzed the current professional situation and future prospects of ophthalmologists under 49 years old. METHODS: The survey of members of the German Association of Ophthalmologists (Berufsverband der Augenärzte Deutschlands) and the German Ophthalmologic Society (Deutsche Ophthalmologische Gesellschaft) was conducted in 2022. All members under the age of 49 years received an online questionnaire on the current professional situation as well as future perspectives (desired working hours, form of organization). The results of the survey were additionally compared with the 2016 survey of the German Association of Ophthalmologists. A similar questionnaire was used at that time. RESULTS: A total of 1014 people participated in the survey (62.7% women, mean age 39.3 ± 8 years, 75.6% specialists). The response rate to the survey was 25%. Specialist practice from 0 to 5 years showed a higher number of employed ophthalmologists (21% self-employed vs. 32% employed); over time the number of self-employed ophthalmologists increased (6-10 years: 40%, > 10 years: 59.3%). Overall, 46% of women were employed in a practice compared with 33% of men. Of the self-employed specialists, 95.9% said they planned to work in the same type of employment in 10 years as currently. Regarding ophthalmologists' career future, the other employment types showed a desire to move to independent practice. Compared to the 2016 survey, gender differences related to the current type of employment were evident. The number of self-employed women decreased from 43% to 26% and self-employed men decreased from 63% to 39%. The number of ophthalmologists in ambulatory healthcare centers was doubled compared to 2016. Ophthalmologists reported similar future perspectives at both survey times. CONCLUSION: The results of the survey of ophthalmologists under 49 years in Germany showed similar perceptions as in 2016. It became clear that the desire to be self-employed in 10 years is very high; however, ophthalmologists expected large practices or medical care centers to prevail in the market. The number of self-employed doctors is decreasing and the desire for self-employment is difficult to realize.


Subject(s)
Ophthalmologists , Ophthalmology , Physicians , Male , Humans , Female , Adult , Middle Aged , Surveys and Questionnaires , Employment
2.
Intell Based Med ; 6: 100071, 2022.
Article in English | MEDLINE | ID: mdl-35958674

ABSTRACT

Background: The COVID-19 pandemic continues to overwhelm intensive care units (ICUs) worldwide, and improved prediction of mortality among COVID-19 patients could assist decision making in the ICU setting. In this work, we report on the development and validation of a dynamic mortality model specifically for critically ill COVID-19 patients and discuss its potential utility in the ICU. Methods: We collected electronic medical record (EMR) data from 3222 ICU admissions with a COVID-19 infection from 25 different ICUs in the Netherlands. We extracted daily observations of each patient and fitted both a linear (logistic regression) and non-linear (random forest) model to predict mortality within 24 h from the moment of prediction. Isotonic regression was used to re-calibrate the predictions of the fitted models. We evaluated the models in a leave-one-ICU-out (LOIO) cross-validation procedure. Results: The logistic regression and random forest model yielded an area under the receiver operating characteristic curve of 0.87 [0.85; 0.88] and 0.86 [0.84; 0.88], respectively. The recalibrated model predictions showed a calibration intercept of -0.04 [-0.12; 0.04] and slope of 0.90 [0.85; 0.95] for logistic regression model and a calibration intercept of -0.19 [-0.27; -0.10] and slope of 0.89 [0.84; 0.94] for the random forest model. Discussion: We presented a model for dynamic mortality prediction, specifically for critically ill COVID-19 patients, which predicts near-term mortality rather than in-ICU mortality. The potential clinical utility of dynamic mortality models such as benchmarking, improving resource allocation and informing family members, as well as the development of models with more causal structure, should be topics for future research.

3.
Acta Neurol Scand ; 130(1): 46-52, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24571587

ABSTRACT

OBJECTIVES: There is convergent evidence for an important role of interleukin-16 (IL-16) in the pathogenesis of multiple sclerosis (MS). IL-16 serves as a chemoattractant for different immune cells that are involved in developing lesions. Here, we compared IL-16 levels of MS patients and controls and addressed the long-term effect of IFN-ß, the most common immunomodulatory MS therapy, on IL-16 serum levels in MS patients over 2 years. Beyond this, we analysed the expression of IL-16 in two CD4(+) T-cell subsets, Th1 and Th17 cells, which are important autoimmune mediators and affected by IFN-ß treatment, derived from myelin-specific T-cell transgenic mice. MATERIALS AND METHODS: IL-16 serum levels of 17 controls and of 16 MS patients before therapy and at months 1, 2, 3, 6, 9, 12 and 24 during IFN-ß1a therapy were determined by ELISA. MRI was performed before therapy, at months 12 and 24. IL-16 expression of in vitro differentiated murine myelin oligodendrocyte glycoprotein (MOG)-specific Th1 and Th17 cells was quantified by real-time PCR. RESULTS: Before therapy, MS patients showed significantly elevated IL-16 levels compared with controls irrespective of disease activity determined by MRI. Therapy with IFN-ß1a led to a significant linear decrease in IL-16 serum levels beginning after 2 months. MOG-specific Th17 cells expressed more IL-16 than Th1 cells. CONCLUSIONS: Reduction in increased IL-16 levels may be of relevance for the therapeutic effect of IFN-ß1a in MS. Easily accessible IL-16 serum levels hold a potential as biomarker of treatment efficacy in MS.


Subject(s)
Immunologic Factors/therapeutic use , Interferon-beta/therapeutic use , Interleukin-16/blood , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Multiple Sclerosis, Relapsing-Remitting/immunology , Adult , Animals , Enzyme-Linked Immunosorbent Assay , Female , Humans , Interferon beta-1a , Interleukin-16/biosynthesis , Interleukin-16/immunology , Magnetic Resonance Imaging , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Middle Aged , Multiple Sclerosis, Relapsing-Remitting/blood , Real-Time Polymerase Chain Reaction , Th1 Cells/immunology , Th1 Cells/metabolism , Th17 Cells/immunology , Th17 Cells/metabolism , Young Adult
4.
B-ENT ; 9(3): 247-50, 2013.
Article in English | MEDLINE | ID: mdl-24273957

ABSTRACT

OBJECTIVE: To describe the clinical characteristics of a 70-year-old female with occipital neuropathy following bone conduction device surgery. DESCRIPTION: A 65-year-old woman underwent bone conduction device placement surgery on the left temporal bone. Postoperatively she progressively developed chronic pain at the implantation site. The pain led to minimal neck movement, which resulted in complaints of the shoulder and arm on the left side. She was treated by an orthopaedic surgeon for a frozen shoulder. Pain medication and occipital nerve blocking had no sustained effect on the pain. DISCUSSION: Occipital neuropathy is a syndrome with continuous aching involving the occipital and parietal scalp caused by trauma or peripheral compression of the occipital nerves. The most common causes of occipital neuropathy are probably direct trauma to the nerve and hypertrophic fibrosis of subcutaneous tissue surrounding the nerve. Scar formation after surgery may therefore cause entrapment of the nerve. CONCLUSION: We describe a case of occipital neuropathy as a complication of BAHA surgery.


Subject(s)
Hearing Aids , Peripheral Nervous System Diseases/etiology , Prosthesis Implantation/adverse effects , Aged , Bone Conduction , Female , Humans
5.
Hum Mov Sci ; 28(2): 236-49, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19110332

ABSTRACT

Chapman [Chapman, S. (1968). Catching a baseball. American Journal of Physics, 36, 868-870] showed that a catcher may be guided to the landing spot of a fly ball by zeroing out its optical acceleration. Subsequently, various studies have provided evidence for what is now known as the Chapman strategy. However, in those studies the catcher's own acceleration and the visuo-motor delay were ignored. This raises the question whether the Chapman strategy still provides an accurate description if those factors are taken into account. To address this question, we implemented the Chapman strategy in a forward dynamical model of the catcher's locomotion in relation to the ball's actual trajectory. Numerical simulations of the model revealed that catching performance was still successful under a broad range of ball trajectories. Furthermore, the model simulations largely reproduced the real running paths reported by McLeod and Dienes [McLeod, P., & Dienes, Z. (1996). Do fielders know where to go to catch the ball or only how to get there? Journal of Experimental Psychology: Human Perception and performance, 22, 531-543]. However, the simulations also revealed that real running paths exhibit some detailed characteristics that appear to be irreconcilable with the Chapman strategy.


Subject(s)
Baseball , Fixation, Ocular , Psychomotor Performance , Space Perception , Humans , Models, Biological , Visual Fields
6.
J Mol Biol ; 382(2): 371-84, 2008 Oct 03.
Article in English | MEDLINE | ID: mdl-18638483

ABSTRACT

Efficient enzyme catalysis depends on exquisite details of structure beyond those resolvable in typical medium- and high-resolution crystallographic analyses. Here we report synchrotron-based cryocrystallographic studies of natural substrate complexes of the flavoenzyme human glutathione reductase (GR) at nominal resolutions between 1.1 and 0.95 A that reveal new aspects of its mechanism. Compression in the active site causes overlapping van der Waals radii and distortion in the nicotinamide ring of the NADPH substrate, which enhances catalysis via stereoelectronic effects. The bound NADPH and redox-active disulfide are positioned optimally on opposite sides of the flavin for a 1,2-addition across a flavin double bond. The new structures extend earlier observations to reveal that the redox-active disulfide loop in GR is an extreme case of sequential peptide bonds systematically deviating from planarity--a net deviation of 53 degrees across five residues. But this apparent strain is not a factor in catalysis, as it is present in both oxidized and reduced structures. Intriguingly, the flavin bond lengths in oxidized GR are intermediate between those expected for oxidized and reduced flavin, but we present evidence that this may not be due to the protein environment but instead due to partial synchrotron reduction of the flavin by the synchrotron beam. Finally, of more general relevance, we present evidence that the structures of synchrotron-reduced disulfide bonds cannot generally be used as reliable models for naturally reduced disulfide bonds.


Subject(s)
Glutathione Reductase/chemistry , Protein Conformation , Binding Sites , Catalysis , Crystallography, X-Ray , Disulfides/chemistry , Flavin-Adenine Dinucleotide/chemistry , Flavin-Adenine Dinucleotide/metabolism , Glutathione Reductase/metabolism , Humans , Models, Molecular , Molecular Sequence Data , NADP/chemistry , NADP/metabolism , Oxidation-Reduction
7.
Brain ; 131(Pt 6): 1455-63, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18474519

ABSTRACT

B cells are increasingly recognized as major players in multiple sclerosis pathogenesis. The BAFF/APRIL system is crucial for B cell homoeostasis and may drive B cell-dependent autoimmunity. We asked whether this system is affected by Interferon (IFN)-beta therapy. We analysed transcription of the ligands (BAFF, APRIL, TWE-PRIL) and the corresponding receptors (BAFF-R, TACI and BCMA) by TaqMan-PCR ex vivo in whole blood and in immune cell subsets purified from IFN-beta-treated multiple sclerosis patients. Serum BAFF concentrations were determined by ELISA. This cross-sectional study involved 107 donors. IFN-beta therapy strongly induced BAFF transcription proportionally to the IFN-beta biomarker MxA in monocytes and granulocytes in vivo. BAFF serum concentrations were elevated in IFN-beta-treated multiple sclerosis patients to a similar level as observed in SLE patients. In cultured PBMC, neutrophils, fibroblasts and astrocytes, BAFF was induced by IFN-beta concentrations similar to those reached in vivo in treated multiple sclerosis patients. BAFF turned out to be the main regulated element of the BAFF/APRIL system. In untreated multiple sclerosis patients, there was no BAFF increase as compared to healthy controls. Our study reveals a complex situation. We show that IFN-beta therapy induces a potent B cell survival factor, BAFF. However, B cell depletion would be desirable at least in some multiple sclerosis patients. The systemic induction of BAFF by IFN-beta therapy may facilitate the production of various autoantibodies and of IFN-neutralizing antibodies. Individual MS/NMO patients who have major B cell involvement may benefit less than others from IFN-beta therapy, thus explaining interindividual differences of the therapeutic response.


Subject(s)
B-Cell Activating Factor/metabolism , B-Lymphocytes/drug effects , Immunotherapy/methods , Interferon-beta/therapeutic use , Multiple Sclerosis/drug therapy , Adult , Autoimmunity , B-Cell Activating Factor/blood , B-Cell Activation Factor Receptor/metabolism , B-Lymphocytes/immunology , Case-Control Studies , Cells, Cultured , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Interferon-beta/analysis , Male , Multiple Sclerosis/immunology , Tumor Necrosis Factor Ligand Superfamily Member 13/metabolism
9.
Rheumatol Int ; 26(5): 427-31, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16001181

ABSTRACT

Osteoporosis is prevalent in men with an estimated one in eight men older than 50 years suffering from osteoporotic fracture, and a higher mortality rate after fracture among men compared with women. There are few approved therapies for osteoporosis in men. This observational study assesses the efficacy and safety of risedronate in the treatment of men with primary and secondary osteoporosis. A single-center, open label, randomized, prospective 1-year study was conducted in men with primary or secondary osteoporosis. Patients were randomized to risedronate (risedronate 5 mg/day plus calcium 1,000 mg/day and vitamin D 800 IU/day) or control groups (alfacalcidol 1 mug/day plus calcium 500 mg/day or vitamin D 1,000 IU/day plus calcium 800 mg/day). Bone mineral density (BMD) measurements, X-rays of the spine, a medical history and physical exam, and patient self-assessments of back pain were performed at baseline and 12 months. Blinded semi-quantitative fracture assessment was conducted by a radiologist. A total of 316 men with osteoporosis were enrolled in the trial (risedronate, n=158; control, n=158). At 1 year lumbar spine BMD increased by 4.7% in the risedronate group versus an increase of 1.0% in the control group (P<0.001). Significant increases in BMD at the total hip and femoral neck were also observed with risedronate compared with the control group. The incidence of new vertebral fracture in the risedronate group was reduced by 60% versus the control group (P=0.028). Daily treatment with risedronate for 12 months significantly increased BMD at the lumbar spine, femoral neck and total hip and significantly reduced the incidence of new vertebral fractures. This is the first prospective, randomized, controlled trial to demonstrate a significant reduction in vertebral fractures in 1 year in men with primary or secondary osteoporosis.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Bone Density/drug effects , Etidronic Acid/analogs & derivatives , Fractures, Bone/prevention & control , Osteoporosis/drug therapy , Spine , Aged , Back Pain/prevention & control , Calcium/therapeutic use , Etidronic Acid/therapeutic use , Humans , Male , Middle Aged , Prospective Studies , Risedronic Acid , Vitamin D/therapeutic use
10.
Osteoporos Int ; 16(12): 2063-8, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16228105

ABSTRACT

Localized transient osteoporosis (LTO; bone marrow edema syndrome) is a rare disorder of generally unknown etiology that is characterized by acute onset of disabling bone pain. Treatment options are currently limited and largely ineffective. The locally increased bone turnover and low bone mineral density (BMD) typical of LTO indicate a potential role for bisphosphonate therapy. Ibandronate, a potent nitrogen-containing bisphosphonate, has proven efficacy in the management of postmenopausal osteoporosis and corticosteroid-induced osteoporosis when administered as a convenient intermittent intravenous (i.v.) injection with a between-dose interval of 2 or 3 months. In a study of 12 patients with LTO, ibandronate was administered as an initial 4-mg i.v. dose with a second, optional injection of 2 mg at 3 months. Daily calcium and vitamin D supplements were provided. Pain was measured at baseline and at 1, 2, 3, and 6 months using a visual analog scale (VAS) of 1-10, and BMD was measured at baseline and 6 months. I.v. ibandronate provided rapid and substantial pain relief. The mean (SD) VAS score decreased from 8.4 (1.3) at baseline to 0.5 (0.7) at 6 months, at which time seven patients had achieved complete pain relief. At 6 months, mean lumbar spine BMD had increased by 4.0% (range -0.8 to 7.7%) in the overall population. I.v. ibandronate injection affords advantages over currently available oral and i.v. bisphosphonates and thus offers a promising therapeutic advance in the treatment of LTO.


Subject(s)
Bone Density Conservation Agents/administration & dosage , Diphosphonates/administration & dosage , Osteoporosis/drug therapy , Pain/drug therapy , Adult , Bone Density/physiology , Bone Density Conservation Agents/adverse effects , Bone Marrow/physiopathology , Bone Resorption/physiopathology , Calcium, Dietary/administration & dosage , Dietary Supplements , Diphosphonates/adverse effects , Edema/drug therapy , Edema/physiopathology , Female , Humans , Ibandronic Acid , Injections, Intravenous , Lumbar Vertebrae/physiopathology , Male , Middle Aged , Osteoporosis/physiopathology , Pain/physiopathology , Pain Measurement/methods , Quality of Life , Syndrome , Treatment Outcome , Vitamin D/administration & dosage
11.
Rheumatol Int ; 25(4): 296-300, 2005 May.
Article in English | MEDLINE | ID: mdl-15770482

ABSTRACT

In a three-year pilot study on 52 women with severe postmenopausal osteoporosis, treatment with etidronate followed by calcium and vitamin D (ECaD) was compared to etidronate followed by monofluorophosphate, calcium and vitamin D (EFCaD). BMD in lumbar spine, total hip and femoral neck increased significantly more with EFCaD than with ECaD. Pain-mobility score decreased significantly more with EFCaD than with ECaD (p=0.006). New vertebral fractures occurred in three patients under EFCaD (12%) and in nine under ECaD (35%), (p=0.048). Three patients under EFCaD (12%) and 15 under ECaD (58%) did not respond to therapy (p of difference=0.001). Mild or moderate adverse reactions were reported by 25 patients, with no significant difference between the two groups. The pilot study suggests that etidronate, sequentially followed by monofluorophosphate, could be a safe, effective and relatively inexpensive therapy in severe postmenopausal osteoporosis.


Subject(s)
Calcium/administration & dosage , Etidronic Acid/therapeutic use , Fluorides/therapeutic use , Fractures, Spontaneous/prevention & control , Osteoporosis, Postmenopausal/therapy , Phosphates/therapeutic use , Vitamin D/administration & dosage , Absorptiometry, Photon , Aged , Bone Density/drug effects , Bone and Bones/diagnostic imaging , Bone and Bones/metabolism , Calcaneus/diagnostic imaging , Calcaneus/drug effects , Calcaneus/physiopathology , Dietary Supplements , Drug Therapy, Combination , Female , Humans , Osteoporosis, Postmenopausal/metabolism , Osteoporosis, Postmenopausal/physiopathology , Pain/physiopathology , Pain/prevention & control , Pilot Projects , Range of Motion, Articular/drug effects , Spinal Fractures/diagnostic imaging , Spinal Fractures/prevention & control , Treatment Outcome , Ultrasonography
12.
J Cell Sci ; 117(Pt 8): 1547-52, 2004 Mar 15.
Article in English | MEDLINE | ID: mdl-15020681

ABSTRACT

Members of the ezrin-radixin-moesin (ERM) protein family serve as regulated microfilament-membrane crosslinking proteins that, upon activation, bind the scaffolding protein ERM-phosphoprotein of 50 kDa (EBP50). Here we report a 3.5 A resolution diffraction analysis of a complex between the active moesin N-terminal FERM domain and a 38 residue peptide from the C terminus of EBP50. This crystallographic result, combined with sequence and structural comparisons, suggests that the C-terminal 11 residues of EBP50 binds as an alpha-helix at the same site occupied in the dormant monomer by the last 11 residues of the inhibitory moesin C-terminal tail. Biochemical support for this interpretation derives from in vitro studies showing that appropriate mutations in both the EBP50 tail peptide and the FERM domain reduce binding, and that a peptide representing just the C-terminal 14 residues of EBP50 also binds to moesin. Combined with the recent identification of the I-CAM-2 binding site on the ERM FERM domain (Hamada, K., Shimizu, T., Yonemura, S., Tsukita, S., and Hakoshima, T. (2003) EMBO J. 22, 502-514), this study reveals that the FERM domain contains two distinct binding sites for membrane-associated proteins. The contribution of each ligand to ERM function can now be dissected by making structure-based mutations that specifically affect the binding of each ligand.


Subject(s)
Microfilament Proteins/chemistry , Microfilament Proteins/metabolism , Phosphoproteins/metabolism , Amino Acid Sequence , Binding Sites , Crystallography, X-Ray , Cytoskeletal Proteins , Escherichia coli/genetics , Humans , Microfilament Proteins/genetics , Models, Molecular , Molecular Sequence Data , Mutagenesis, Site-Directed , Phosphoproteins/chemistry , Point Mutation , Protein Binding , Protein Folding , Protein Structure, Secondary , Protein Structure, Tertiary , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Sequence Homology, Amino Acid
13.
Rheumatol Int ; 24(2): 110-3, 2004 Mar.
Article in English | MEDLINE | ID: mdl-13680141

ABSTRACT

Our trial was a 3-year, open-label, prospective, comparative, clinical study comparing the effects of oral alendronate (ALN), 10 mg daily, and alfacalcidol (AC), 1 microg daily, on bone mineral density (BMD), fracture events, height, back pain, safety and tolerability in 134 men with established primary osteoporosis. All men received 500 mg calcium daily. BMD was measured at the lumbar spine and femoral neck using dual-energy X-ray absorptiometry (DXA). Spine radiographs were obtained at baseline and every 12 months thereafter, and were evaluated by a radiologist blinded to treatment assignment. At 3 years, AC-treated patients showed a significant mean increase of 3.5% in lumbar spine BMD, compared with a mean increase of 11.5% in men receiving ALN ( p<0.0001 between groups). The corresponding increases in femoral neck BMD were 2.3% and 5.8% for the AC and ALN groups, respectively ( p=0.0015 between groups). Over 3 years, new vertebral fractures occurred in 24.2% of the AC-treated patients and in 10.3% of the ALN-treated patients ( p=0.040). ALN-treated patients also had a significantly lower height loss. There were no between-group differences regarding nonvertebral fractures or changes in back pain. Both therapies were well tolerated, with a compliance rate >90%. We conclude that although AC has significant effects on BMD, ALN has greater effects on BMD and fracture efficacy.


Subject(s)
Alendronate/administration & dosage , Diphosphonates/administration & dosage , Osteoporosis/drug therapy , Adjuvants, Immunologic/administration & dosage , Administration, Oral , Body Height/drug effects , Bone Density/drug effects , Calcium/administration & dosage , Humans , Hydroxycholecalciferols/administration & dosage , Male , Metals, Alkaline Earth/administration & dosage , Osteoporosis/complications , Osteoporosis/physiopathology , Prospective Studies , Sex Factors , Spinal Fractures/etiology , Spinal Fractures/prevention & control , Treatment Outcome
14.
Rheumatol Int ; 24(2): 63-70, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14513268

ABSTRACT

Supplementation therapy with plain vitamin D plus calcium is in general regarded as effective prevention or first-step treatment of glucocorticoid-induced osteoporosis (GIOP). The aim of our study was to compare the therapeutic efficacy of the D-hormone analog alfacalcidol with plain vitamin D in patients with established GIOP with or without vertebral fractures. Patients on long-term glucocorticoid (GC) therapy were included as matched pairs to receive randomly either 1 microg alfacalcidol plus 500 mg calcium per day (group A, n=103) or 1000 IU vitamin D3 plus 500 mg calcium (group B, n=101). The two groups were well matched in terms of mean age, sex ratio, mean height and weight, daily dosage, and duration of GC therapy, and the percentages of the three underlying diseases included chronic obstructive pulmonary disease, rheumatoid arthritis, and polymyalgia rheumatica. The baseline mean bone mineral density (BMD) values at the lumbar spine for the two groups were -3.26 (alfacalcidol) and -3.25 (vitamin D(3)) and, at the femoral neck, -2.81 and -2.84, respectively (T scores). Rates of prevalent vertebral and nonvertebral fractures did not differ between groups. During the 3-year study, we observed a median percentage increase of BMD at the lumbar spine of 2.4% in group A and a loss of 0.8% in group B ( P<0.0001). There also was a larger median increase at the femoral neck in group A (1.2%) than in group B (0.8%) ( P<0.006). The 3-year rates of patients with at least one new vertebral fracture were 9.7% among those assigned to the alfacalcidol group and 24.8% in the vitamin D group (risk reduction 0.61, 95% CI 0.24-0.81, P=0.005). The 3-year rates of patients with at least one new nonvertebral fracture were 15% in the alfacalcidol group and 25% in the vitamin D group (risk reduction 0.41, 95% CI 0.06-0.68, P=0.081). The 3-year rates of patients with at least one new fracture of any kind were 19.4% among those treated with alfacalcidol and 40.65% with vitamin D (risk reduction 0.52, 95% CI 0.25-0.71, P=0.001). In accordance with the observed fracture rates, the alfacalcidol group showed a substantially larger decrease in back pain than the plain vitamin D group ( P<0.0001). Generally, side effects in both groups were mild, and only three patients in the alfacalcidol group and two in the vitamin D group had moderate hypercalcemia. We conclude that alfacalcidol plus calcium is highly superior to plain vitamin D3 plus calcium in the treatment of established GIOP.


Subject(s)
Adjuvants, Immunologic/therapeutic use , Cholecalciferol/therapeutic use , Hydroxycholecalciferols/therapeutic use , Osteoporosis/drug therapy , Vitamins/therapeutic use , Aged , Calcium/therapeutic use , Female , Glucocorticoids/adverse effects , Humans , Male , Metals, Alkaline Earth/therapeutic use , Middle Aged , Osteoporosis/chemically induced , Spinal Fractures/chemically induced , Spinal Fractures/drug therapy , Treatment Outcome
15.
Photosynth Res ; 81(3): 303-15, 2004.
Article in English | MEDLINE | ID: mdl-16034534

ABSTRACT

Ferredoxin reductase (FNR) is ubiquitous among photosynthetic organisms as the enzyme directly responsible for the generation of NADPH. Structural studies over the last 15 years have generated over 30 crystal structures of wild-type and mutant FNRs that have yielded a great deal of insight into its structure-function relations. These insights are summarized and combined to propose a structurally informed cycle for FNR catalysis in vivo.

16.
Osteoporos Int ; 14(10): 801-7, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14610641

ABSTRACT

Despite its well-known benefits, chronic corticosteroid therapy causes osteoporotic fractures in approximately 30-50% of patients treated. To prevent the occurrence of these fractures, treatment with oral bisphosphonates is recommended. However, current oral bisphosphonates, which are given either daily or weekly, are associated with stringent, inconvenient dosing guidelines. Less frequent dosing may provide greater acceptability. The objective of this study was to investigate the efficacy and safety of ibandronate, a highly potent nitrogen-containing bisphosphonate, when given by intravenous (i.v.) injection every 3 months in men and women with established corticosteroid-induced osteoporosis (CIO; lumbar spine [L2-L4] bone mineral density [BMD] T-score < or =-2.5). A total of 115 participants were assigned to receive daily calcium supplements (500 mg) plus either ibandronate (2 mg) injections every 3 months or daily oral alfacalcidol (1 microg), for 3 years. Intermittent i.v. ibandronate injections produced significantly greater increases in mean BMD at the lumbar spine (13.3% versus 2.6%, respectively; p<0.001), and femoral neck (5.2% versus 1.9%, respectively; p<0.001) versus daily oral alfacalcidol, after 3 years, relative to baseline. This study was not statistically powered to show a difference between the groups with respect to fracture incidence. Nevertheless, after 36 months, the frequency of patients with new vertebral fractures was significantly lower in the patients receiving ibandronate relative to those taking alfacalcidol (8.6% versus 22.8%, respectively; p=0.043). This is the first time that significant vertebral fracture reduction has been demonstrated with an i.v. bisphosphonate in CIO. Patients treated with i.v. ibandronate injections also experienced less back pain (p<0.001) and less height loss (p=0.001) than those receiving oral alfacalcidol. Both regimens were well tolerated. In conclusion, intermittent i.v. ibandronate injections are efficacious, well-tolerated, and convenient, and promise to offer physicians an important therapeutic advance in the management of osteoporosis.


Subject(s)
Diphosphonates/therapeutic use , Glucocorticoids/adverse effects , Osteoporosis/complications , Spinal Fractures/prevention & control , Aged , Back Pain/prevention & control , Body Height/drug effects , Bone Density/drug effects , Diphosphonates/adverse effects , Drug Administration Schedule , Female , Humans , Hydroxycholecalciferols/therapeutic use , Ibandronic Acid , Injections, Intravenous , Male , Middle Aged , Osteoporosis/chemically induced , Osteoporosis/physiopathology , Spinal Fractures/etiology
17.
Cancer Genet Cytogenet ; 146(1): 48-57, 2003 Oct 01.
Article in English | MEDLINE | ID: mdl-14499696

ABSTRACT

Occurrence of 13q14 deletions between D13S273 and D13S25 in B-cell chronic lymphocytic leukemia (B-CLL) suggests that the region contains a tumor suppressor gene. We constructed a PAC/cosmid contig largely corresponding to a 380-kb 13q14 YAC insert that we found deleted in a high proportion of B-CLL patients. We found seven genes by exon trapping, cDNA screening and analysis/cDNA extension of known expressed sequence tags. One appeared to originate from another region of 13q. Recent publications have focused on two of the genes that most likely do not have a tumor suppressor role. This study evaluates the remaining four genes in the region by mutation scanning and theoretical analysis of putative encoded products. No mutations suggestive of a pathogenic effect were found. The 13q14 deletions may be a consequence of an inherent instability of the region, an idea supported by our finding of a considerable proportion of AluY repeats. Deletion of putative enhancer sequences and/or genes in the region may result in an inactivation of tumor suppression by a haploinsufficiency mechanism. We conclude that RFP2, c13ORF1, and a chromosome 13-specific ST13-like gene, FAM10A4, are the most likely candidates for such a type of B-CLL TSG.


Subject(s)
B-Lymphocytes/pathology , Genes, Tumor Suppressor , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Chromosome Mapping , Chromosomes, Human, Pair 13 , DNA Mutational Analysis , Expressed Sequence Tags , Humans , In Situ Hybridization, Fluorescence , Sequence Deletion
18.
Rheumatology (Oxford) ; 42(6): 743-9, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12730532

ABSTRACT

OBJECTIVE: Corticosteroids are widely prescribed, although treatment-related side-effects are common. Of these adverse events (AEs), osteoporosis is considered the most serious. Currently, oral bisphosphonates are the standard treatment for corticosteroid-induced osteoporosis (CIO). However, intermittent intravenous (i.v.) therapy may have advantages, including lack of gastrointestinal AEs, improved bioavailability and increased compliance. This study investigated the efficacy and safety of 3-monthly i.v. ibandronate bolus injections in patients with established CIO. The results from a planned 2-yr interim analysis are reported. METHOD: In this controlled, prospective, open-label, parallel-group study, 104 patients (49 men and 55 women) with established CIO (mean T-score <-2.5 s.d. at the lumbar spine (L2-L4) received daily calcium (500 mg) plus either 3-monthly i.v. ibandronate (2 mg) bolus injections or oral daily alfacalcidol (1 micro g). The primary end-point was bone mineral density (BMD) change at the lumbar spine, femoral neck and calcaneus after 24 months. RESULTS: Compared with oral daily alfacalcidol, i.v. ibandronate produced significantly superior gains in mean (+/-s.d.) BMD at the lumbar spine (2.2+/-3.1 vs 11.9+/-7.4%; P<0.001), femoral neck (1.3+/-1.8 vs 4.7+/-4.0%; P<0.001) and calcaneus (7.6+/-3.8 vs 15.5+/-10.7%; P<0.0001) after 2 yr. Consistent with these BMD gains and, although the study was not powered for fractures, a trend towards a reduction in vertebral fractures and greater back pain relief was seen in the ibandronate group. The overall incidence of AEs was similar in the two treatment arms. CONCLUSIONS: Three-monthly i.v. ibandronate bolus injections are significantly superior to alfacalcidol in the treatment of CIO. These data confirm the potential of ibandronate for the treatment of osteoporosis associated with corticosteroid use. The ease of administration, lack of AEs and good compliance associated with intermittent i.v. ibandronate make it a potentially valuable alternative to oral bisphosphonate therapy for the treatment of CIO.


Subject(s)
Diphosphonates/administration & dosage , Glucocorticoids/adverse effects , Osteoporosis/drug therapy , Aged , Back Pain/drug therapy , Bone Density/drug effects , Calcaneus/physiopathology , Diphosphonates/therapeutic use , Drug Administration Schedule , Female , Femur Neck/physiopathology , Humans , Hydroxycholecalciferols/therapeutic use , Ibandronic Acid , Injections, Intravenous , Lumbar Vertebrae/physiopathology , Male , Middle Aged , Osteoporosis/chemically induced , Osteoporosis/physiopathology , Prospective Studies , Spinal Fractures/prevention & control
19.
Int J Radiat Biol ; 79(9): 689-700, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14703942

ABSTRACT

PURPOSE: To investigate dose distributions in partial-volume irradiation experiments in small experimental animals, in particular the parotid gland of rat. MATERIALS AND METHODS: High-resolution magnetic resonance imaging images were made that provided the outlines of the parotid glands, which were used to design collimators with conformal radiation ports for 100 and 50% cranial/caudal partial-volume irradiation. A protocol for absolute dosimetry was designed and relative dose measurements were performed. From the three-dimensional topographical data and the three-dimensional dose distribution, dose-volume histograms were determined. RESULTS: The standard uncertainty of absorbed entrance dose was within 3%. Radiochromic film, thermoluminescence dosemeters and ionization chamber dose measurements revealed that the relative doses measured were in good agreement. The 20-80% penumbra of the beam across the 50% field edge was only 0.4 mm at a 6 mm depth. The gradient of the percentage depth dose from the skin of the rat to a depth of 12 mm was 1.5% mm(-1). The absorbed doses in the cranial 50% and the caudal 50% partial volumes were comparable. This finding was reflected in the calculated dose-volume histograms of the different regions, which were similar. The dose in the shielded area between the left and right ports was about 14% of the dose near the centres of the beams. CONCLUSION: The designed set-up showed that irradiation of small volumes could be performed with high accuracy allowing the study of differences in radiation damage. Similar doses were given to the 50% cranial and 50% caudal gland volumes and, therefore, a possible difference in radiosensitivity in these volumes was not a dose effect. The approach used was also applicable for the irradiation of small volumes of other tissues.


Subject(s)
Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Parotid Gland/anatomy & histology , Radiation Dosage , Radiation Protection/methods , Radiometry/methods , Radiotherapy Planning, Computer-Assisted/methods , Animals , Body Burden , Cohort Studies , Feasibility Studies , Male , Parotid Gland/radiation effects , Phantoms, Imaging , Radiation Tolerance , Radiotherapy Planning, Computer-Assisted/instrumentation , Rats , Rats, Wistar , Subtraction Technique
20.
Rheumatol Int ; 22(5): 199-203, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12215866

ABSTRACT

Pain relief for patients with osteoporosis is important to maintain mobility and facilitate physical therapy. Transdermal fentanyl may be useful but has not been studied systematically. Patients with at least one osteoporotic vertebral fracture requiring strong opioids were enrolled and received transdermal fentanyl. Treatment history, pain, ease of physical therapy, and quality of life were recorded at baseline and after 4 weeks. Of 64 patients enrolled, 49 completed the study; 12 withdrew because of adverse events, most commonly nausea, vomiting, or dizziness. Pain at rest and on movement decreased significantly from baseline to final assessment (mean scores 7.84 and 8.55, respectively, at baseline, falling to 3.56 and 4.50 after 4 weeks). Quality of life improved significantly, and 61% of patients were satisfied with the treatment. Ability to undergo physical therapy improved significantly. Transdermal fentanyl is useful for the treatment of severe back pain caused by osteoporosis.


Subject(s)
Analgesics, Opioid/administration & dosage , Back Pain/drug therapy , Back Pain/etiology , Fentanyl/administration & dosage , Osteoporosis/complications , Quality of Life , Administration, Cutaneous , Aged , Aged, 80 and over , Back Pain/physiopathology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Osteoporosis/diagnosis , Pain Measurement , Patient Satisfaction , Probability , Prospective Studies , Severity of Illness Index , Spinal Diseases/complications , Spinal Diseases/diagnosis , Statistics, Nonparametric , Treatment Outcome
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