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1.
Handchir Mikrochir Plast Chir ; 48(2): 78-84, 2016 Apr.
Article in German | MEDLINE | ID: mdl-27100943

ABSTRACT

BACKGROUND: There has been ongoing development in the field of 3-dimensional (3-D) Surface Imaging by laser scanner and digital 3-D photography (Photogrammetry) in recent years. Manufacturers tend to make new 3-D cameras compact, light-weighted, mobile, and user-friendly, similar to the development on the smartphone market. Although 3D scans have been used for patient consultations and digital documentation in Plastic Surgery since the 1980, there has been no significant development lately regarding its use for objective assistance during surgery. PATIENTS, MATERIAL AND METHODS: Our research team presents a new intraoperative 3-D scanning method for plastic-surgical procedures with selected mobile 3-D scanner systems. In the future, these might assist surgeons with the pre-, post-, and intraoperative 3-D analysis, choice of therapy, consultation, and documentation. RESULTS: The 3-D scanners were successfully validated for their intraoperative application to several patients. With their introduction, an intraoperative, objective measurement of volume to evaluate form and symmetry was possible. CONCLUSION: In this work, we share our first experience with the intraoperative use of new mobile 3D camera systems, discuss pros and cons, and show selected patient examples.


Subject(s)
Image Interpretation, Computer-Assisted/instrumentation , Imaging, Three-Dimensional/instrumentation , Intraoperative Complications/diagnostic imaging , Lasers , Photogrammetry/instrumentation , Plastic Surgery Procedures/instrumentation , Surgery, Computer-Assisted/instrumentation , Adult , Body Surface Area , Documentation , Equipment Design , Female , Humans , Patient Care Planning
2.
Scand J Rheumatol ; 44(6): 456-63, 2015.
Article in English | MEDLINE | ID: mdl-26114440

ABSTRACT

OBJECTIVES: Cationic lipid complexes bind to angiogenic endothelial cells of solid tumours and microvessels of chronic inflammatory tissue. Methotrexate (MTX) is one of the drugs used in the therapy of rheumatoid arthritis (RA); it is applied systemically but can have serious side-effects. The aim of this study was to investigate the impact of MTX encapsulated in cationic liposomes (EndoMTX) in comparison to treatment with free MTX. METHOD: We used an antigen-induced arthritis (AiA) model and investigated the leucocyte- and platelet-endothelial cell interaction in arthritic female C57/Bl6 mice and in healthy controls. The arthritic animals were divided into four different groups receiving either trehalose, free MTX, EndoMTX placebo, or EndoMTX. These parameters and functional capillary density (FCD) were measured and assessed by intravital microscopy (IVM). We controlled clinical parameters such as the knee joint diameter (KJD) throughout the observation period. RESULTS: Animals treated with EndoMTX showed a significant and superior reduction in leucocyte- and platelet-endothelial cell interaction, FCD, and KJD. Free MTX or empty liposomes also showed a reduction in these parameters but not to a significant level. FCD decreased in the EndoMTX group in comparison to using free drugs or empty carrier-like liposomes. CONCLUSIONS: This study demonstrates the advantage of using MTX encapsulated in cationic liposomes in contrast to free and generic MTX, with a higher efficacy in anti-inflammatory and anti-angiogenic abilities. Targeting with cationic liposomes may be a promising treatment option and should be elucidated in further experiments regarding dose reduction and side-effects due to MTX usage.


Subject(s)
Antirheumatic Agents/administration & dosage , Antirheumatic Agents/therapeutic use , Arthritis, Experimental/drug therapy , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/immunology , Methotrexate/administration & dosage , Methotrexate/therapeutic use , Administration, Intravenous , Animals , Antigens, Bacterial/adverse effects , Arthritis, Experimental/chemically induced , Arthritis, Experimental/pathology , Arthritis, Rheumatoid/pathology , Blood Platelets/pathology , Capsules , Cell Communication/physiology , Disease Models, Animal , Endothelial Cells/pathology , Female , Knee Joint/blood supply , Knee Joint/diagnostic imaging , Knee Joint/pathology , Leukocytes/pathology , Liposomes , Mice , Mice, Inbred C57BL , Microcirculation/physiology , Radiography , Treatment Outcome
3.
Opt Lett ; 39(17): 5158-61, 2014 Sep 01.
Article in English | MEDLINE | ID: mdl-25166098

ABSTRACT

We report on the first, to the best of our knowledge, continuous-wave quasi three-level lasers emitting in the cyan-blue spectral range in praseodymium-doped crystalline materials. Applying Pr(3+):BaY2F8 as an active medium, up to 201 mW of output power at 495 nm could be obtained with a slope efficiency of 27% under pumping with an optically pumped semiconductor laser (2ω-OPSL) at 480 nm. In the same pumping scheme using Pr(3+):LiYF4, output powers up to 70 mW were realized at 491 and 500 nm, respectively. With Pr(3+):BaY2F8, diode-pumped laser operation with up to 11% slope efficiency and 44 mW output power was also achieved. In the latter case, detailed investigations on the temperature dependency of the laser output were conducted. Moreover, comparative experiments were carried out for the first time, to the best of our knowledge, with green-emitting Pr(3+):BaY2F8 lasers at 524 and 553 nm both under diode and 2ω-OPSL excitation.

4.
Scand J Rheumatol ; 43(5): 356-63, 2014.
Article in English | MEDLINE | ID: mdl-24825390

ABSTRACT

OBJECTIVES: The use of statins in the prevention and treatment of cardiovascular diseases is well established. Their use as anti-inflammatory and immunomodulatory agents in the treatment of rheumatoid arthritis (RA) has also been investigated, with several clinical and experimental studies indicating an anti-inflammatory effect of statins for RA, but other studies showing no effect or even the opposite. The current study was designed to examine the effect of simvastatin in an in vivo murine model of arthritis using intravital microscopy. METHOD: We assigned four groups (n = 7, female C57Bl6 mice), two with and two without antigen-induced arthritis (AiA), from which one of the non-AiA groups and one of the AiA groups were treated with simvastatin 40 mg/kg i.p. daily for 14 consecutive days after induction of arthritis. Platelet- and leucocyte-endothelial cell interaction was assessed by measurement of rolling and adherent fluorescence-labelled platelets and leucocytes, functional capillary density (FCD) was evaluated, and knee joint diameter was determined as a clinical parameter. RESULTS: In arthritic mice treated with simvastatin, a significant reduction in platelet- and leucocyte-endothelial cell interaction was observed in comparison to arthritic mice treated with vehicle. In addition, a significant reduction in FCD was seen in arthritic mice treated with simvastatin, along with a reduction in knee joint swelling of the AiA mice. CONCLUSIONS: Treatment of AiA mice with simvastatin showed significant reductions in platelet- and leucocyte-endothelial cell interactions, in FCD, and in the swelling of the knee joint. These results support the hypothesis of the anti-inflammatory effects of statins in the treatment of RA.


Subject(s)
Antigens/adverse effects , Arthritis, Experimental/pathology , Blood Platelets/drug effects , Cell Communication/drug effects , Endothelium, Vascular/drug effects , Leukocytes/drug effects , Simvastatin/pharmacology , Animals , Anti-Inflammatory Agents/pharmacology , Arthritis, Experimental/chemically induced , Arthritis, Experimental/immunology , Blood Platelets/pathology , Capillaries/drug effects , Capillaries/pathology , Disease Models, Animal , Endothelium, Vascular/pathology , Female , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Knee Joint/drug effects , Knee Joint/pathology , Leukocytes/pathology , Mice , Mice, Inbred C57BL , Microscopy, Fluorescence
5.
Handchir Mikrochir Plast Chir ; 46(2): 97-104, 2014 Apr.
Article in German | MEDLINE | ID: mdl-24777459

ABSTRACT

BACKGROUND: A new approach of using photographs from smartphones for three-dimensional (3D) imaging was introduced besides the standard high quality 3D camera systems. In this work, we investigated different capture preferences and compared the accuracy of this 3D reconstruction method with manual tape measurement and an established commercial 3D camera system. METHODS: The facial region of one plastic mannequin head was labelled with 21 landmarks. A 3D reference model was captured with the Vectra 3D Imaging System®. In addition, 3D imaging was executed with the Autodesk 123d Catch® application using 16, 12, 9, 6 and 3 pictures from Apple® iPhone 4 s® and iPad® 3rd generation. The accuracy of 3D reconstruction was measured in 2 steps. First, 42 distance measurements from manual tape measurement and the 2 digital systems were compared. Second, the surface-to-surface deviation of different aesthetic units from the Vectra® reference model to Catch® generated models was analysed. For each 3D system the capturing and processing time was measured. RESULTS: The measurement showed no significant (p>0.05) difference between manual tape measurement and both digital distances from the Catch® application and Vectra®. Surface-to-surface deviation to the Vectra® reference model showed sufficient results for the 3D reconstruction of Catch® with 16, 12 and 9 picture sets. Use of 6 and 3 pictures resulted in large deviations. Lateral aesthetic units showed higher deviations than central units. Catch® needed 5 times longer to capture and compute 3D models (average 10 min vs. 2 min). CONCLUSION: The Autodesk 123d Catch® computed models suggests good accuracy of the 3D reconstruction for a standard mannequin model, in comparison to manual tape measurement and the surface-to-surface analysis with a 3D reference model. However, the prolonged capture time with multiple pictures is prone to errors. Further studies are needed to investigate its application and quality in capturing volunteer models. Soon mobile applications may offer an alternative for plastic surgeons to today's cost intensive, stationary 3D camera systems.


Subject(s)
Cell Phone/instrumentation , Computers, Handheld , Image Interpretation, Computer-Assisted/instrumentation , Imaging, Three-Dimensional/instrumentation , Photogrammetry/instrumentation , Plastic Surgery Procedures/instrumentation , Cephalometry/instrumentation , Computer Simulation , Face/anatomy & histology , Humans , Manikins , Software
6.
Opt Lett ; 38(15): 2698-701, 2013 Aug 01.
Article in English | MEDLINE | ID: mdl-23903115

ABSTRACT

We report the fabrication and visible laser operation of Pr,Mg:SrAl12O19 waveguides. Waveguiding structures were created by focusing the radiation of a femtosecond Ti:sapphire laser into bulk material. Guiding losses were determined to be as low as 0.12 dB cm(-1) at 632.8 nm. By employing a frequency-doubled optically pumped semiconductor laser, waveguide laser operation was realized at wavelengths of 525.3, 644.0, and 724.9 nm with output powers as high as 36, 1065, and 504 mW, respectively. To the best of our knowledge this is the first demonstration of green laser operation in a Pr(3+)-doped crystalline waveguide laser.

7.
Opt Lett ; 37(23): 4889-91, 2012 Dec 01.
Article in English | MEDLINE | ID: mdl-23202080

ABSTRACT

In this Letter, we report on laser operation of Pr3+,Mg2+:SrAl12O19 pumped by a frequency-doubled optically pumped semiconductor laser. By employing a V-type cavity, we demonstrate cw laser operation at room temperature in the green spectral range in a doped oxide host for the first time to the best of our knowledge. Furthermore, efficient laser operation was realized in the orange, red, and deep red spectral range with output powers exceeding 1.1 W at emission wavelengths of 643.6 and 724.4 nm.

8.
Opt Express ; 20(18): 20387-95, 2012 Aug 27.
Article in English | MEDLINE | ID: mdl-23037089

ABSTRACT

We report on the first results of diode pumped laser operation of Pr3+:LaF3 in a quasi continuous wave (qcw) mode with average output powers of up to 80.0 mW (≈ 161.3 mW qcw) and a maximum slope efficiency of 37% at 719.8 nm. Furthermore it was possible to operate the laser at 537.1 nm and 635.4 nm and to tune the emission wavelength from 609 nm to 623 nm. The pump source was an InGaN laser diode with a maximum output power of 1 W at a central emission wavelength of 442 nm.


Subject(s)
Lasers, Solid-State , Spectrum Analysis/instrumentation , Equipment Design , Equipment Failure Analysis
9.
Chirurg ; 81(11): 999-1004, 2010 Nov.
Article in German | MEDLINE | ID: mdl-20237747

ABSTRACT

BACKGROUND: The need for red blood cell units in cancer surgery is increasing. The role of the better immunological options, such as preoperative blood donation or intraoperative autologous blood salvage is not known. The aim of this survey was to clarify the transfusion setting and options for cancer patients in Germany. METHOD: A questionnaire was send to 90 directors of surgical departments in Germany. RESULTS: A total of 60 directors answered the questionnaire. In most cases the blood loss is compensated by allogenic blood transfusions. The possibility of preoperative blood donation exists in 85% of the hospitals and is offered in 3% for cancer patients. The intraoperative blood salvage is possible in 93% of the hospitals and 10% use this procedure without an additional purifying process for cancer patients. Of the hospitals 31% are able to irradiate blood collected intraoperatively, but only 11% use this for cancer patients. CONCLUSION: Perioperative blood loss is compensated by allogenic blood transfusion. The better immunological procedures, such as preoperative blood donation or intraoperative blood salvage, are not used because of the higher costs and the possible retransfusion of tumor cells.


Subject(s)
Blood Loss, Surgical/physiopathology , Blood Transfusion, Autologous , Blood Transfusion , Digestive System Neoplasms/surgery , Lung Neoplasms/surgery , Operative Blood Salvage , Data Collection , Digestive System Neoplasms/blood , Germany , Hospitals, University , Humans , Lung Neoplasms/blood , Surveys and Questionnaires
10.
Ground Water ; 47(3): 438-52, 2009.
Article in English | MEDLINE | ID: mdl-18823399

ABSTRACT

To assess the vulnerability of ground water to contamination in the karstic Upper Floridan aquifer (UFA), age-dating tracers and selected anthropogenic and naturally occurring compounds were analyzed in multiple water samples from a public supply well (PSW) near Tampa, Florida. Samples also were collected from 28 monitoring wells in the UFA and the overlying surficial aquifer system (SAS) and intermediate confining unit located within the contributing recharge area to the PSW. Age tracer and geochemical data from the earlier stage of the study (2003 through 2005) were combined with new data (2006) on concentrations of sulfur hexafluoride (SF(6)), tritium ((3)H), and helium-3, which were consistent with binary mixtures of water for the PSW dominated by young water (less than 7 years). Water samples from the SAS also indicated mostly young water (less than 7 years); however, most water samples from monitoring wells in the UFA had lower SF(6) and (3)H concentrations than the PSW and SAS, indicating mixtures containing high proportions of older water (more than 60 years). Vulnerability of the PSW to contamination was indicated by predominantly young water and elevated nitrate-N and volatile organic compound concentrations that were similar to those in the SAS. Elevated arsenic (As) concentrations (3 to 19 microg/L) and higher As(V)/As(III) ratios in the PSW than in water from UFA monitoring wells indicate that oxic water from the SAS likely mobilizes As from pyrite in the UFA matrix. Young water found in the PSW also was present in UFA monitoring wells that tap a highly transmissive zone (43- to 53-m depth) in the UFA.


Subject(s)
Water Movements , Water Pollution/analysis , Water Supply , Florida , United States
11.
Int Orthop ; 32(4): 511-6, 2008 Aug.
Article in English | MEDLINE | ID: mdl-17372732

ABSTRACT

One complication of rheumatoid arthritis (RA) is the involvement of the cervical spine (CS). Although prophylactic stabilisation is recommended, the timing at which this should occur is poorly defined. The aim of our study was to evaluate the course of neurological symptoms in terms of the timing of surgery. A total of 34 patients with RA and CS involvement were surgically stabilised. These patients were classified using the Ranawat (RW) score both preoperatively and at an average of 54 months post-operatively. For each patient, the presence of atlantoaxial and subaxial subluxation as well as vertical migration of the odontoid was recorded. The anterior atlantodental interval was also assessed pre- and post-operatively. Improvement was obtained in 20 patients, the clinical situation remained unchanged in three patients and three patients manifested disease progression. In terms of the RW score, the 16 patients with pre-operative RW grades I-II showed no deterioration at the post-operative follow-up, with 13 of these patients showing an improvement; the 12 patients with pre-operative RW grades IIIA-IIIB did not show any improvement of neurological symptoms at follow-up, although seven of these patients subjectively assessed the symptoms to be less severe after surgery; three other patients showed a worsening of symptoms. Our results suggest that preventive stabilisation of CS in RA leads to acceptable results, although the complications of the surgery are obvious. However, early operative treatment may delay the detrimental course of cervical myelopathy in RA.


Subject(s)
Arthritis, Rheumatoid/surgery , Cervical Vertebrae/surgery , Spinal Fusion/methods , Adult , Aged , Arthritis, Rheumatoid/diagnostic imaging , Atlanto-Axial Joint/diagnostic imaging , Atlanto-Axial Joint/surgery , Cervical Vertebrae/diagnostic imaging , Female , Humans , Joint Dislocations/diagnostic imaging , Joint Dislocations/surgery , Male , Middle Aged , Odontoid Process/diagnostic imaging , Odontoid Process/surgery , Radiography , Time Factors , Treatment Outcome
12.
Inflamm Res ; 56(10): 414-20, 2007 Oct.
Article in English | MEDLINE | ID: mdl-18026698

ABSTRACT

OBJECTIVE: Inflammation is associated with the invasion of leukocytes into affected tissues and with the up-regulation of platelet activation and adhesion. Assuming that leukocyte accumulation is linked to platelet aggregation, the aim of our study was to examine the effects of selective platelet inhibition by the glycoprotein (GP) IIb/IIIa receptor antagonist Tirofiban on the leukocyte-endothelial cell interaction. MATERIAL AND METHODS: We used the model of antigen-induced arthritis (AiA) to induce inflammatory changes in the synovial microcirculation. Ex vivo labelled platelets and in vivo fluorescence-labelled leukocytes were visualized by intravital microscopy (IVM). C57/Bl6 mice were allocated to four groups; two control groups with saline or Tirofiban and two groups with AiA that also received either saline or Tirofiban (0.5 microg/g BW) intravenously. RESULTS: There was no significant change in platelet- or leukocyte- endothelial cell interaction in the endothelium in healthy control animals. In contrast, after selective inhibition of platelets, the platelet- and leukocyte-endothelial cell interaction was significantly reduced in arthritic mice and reached the level of the healthy control groups. CONCLUSION: Selective platelet inhibition by Tirofiban resulted in reduced leukocyte-endothelial cell interactions in AiA. Consequently, platelets contribute to leukocyte adhesion in AiA via GPIIb/IIIa and therefore platelet inhibition could become an additional therapy option in chronic arthritic disease.


Subject(s)
Arthritis, Experimental/drug therapy , Cell Communication/drug effects , Endothelial Cells/drug effects , Leukocytes/drug effects , Platelet Aggregation Inhibitors/pharmacology , Platelet Glycoprotein GPIIb-IIIa Complex/antagonists & inhibitors , Tyrosine/analogs & derivatives , Animals , Arthritis, Experimental/blood , Endothelial Cells/physiology , Female , Leukocytes/physiology , Mice , Mice, Inbred C57BL , Tirofiban , Tyrosine/pharmacology
13.
Scand J Rheumatol ; 36(4): 311-9, 2007.
Article in English | MEDLINE | ID: mdl-17763210

ABSTRACT

OBJECTIVE: Platelets are thought to participate in the pathogenesis of chronic inflammatory diseases such as rheumatoid arthritis (RA). We showed recently an in vivo increase in platelet-endothelial cell interactions in mice with antigen-induced arthritis (AiA). The underlying mechanisms are not yet clear. The aim of this study was to investigate the impact of P-selectin in AiA by means of intravital fluorescence microscopy (IVM). METHODS: C57/Bl6 mice and P-selectin-deficient mice were divided into four groups (n = 7; control/AiA per strain). The extent of AiA was assessed by measuring knee joint swelling and by histological scoring. Rolling and adherent fluorescence-labelled platelets and leucocytes were investigated by IVM. RESULTS: In arthritic P-selectin-deficient mice (rolling: 0.05+/-0.01; adherent: 130+/-20 mm(-2)), compared to arthritic C57/Bl6 mice (rolling: 0.20+/-0.04; adherent: 1910+/-200 mm(-2)), platelet interaction was significantly reduced (p<0.05) and reached the level of both control groups without AiA. In addition, interaction of leucocytes in P-selectin-deficient arthritic animals (rolling: 0.12+/-0.06; adherent: 387+/-37 mm(-2)) was significantly decreased in comparison to arthritic C57/Bl6 animals (rolling: 0.21+/-0.06; adherent: 1492+/-284 mm(-2); p<0.05). Swelling of the knee joint and histological scoring were reduced in arthritic P-selectin-deficient mice compared to arthritic C57/Bl6 mice. CONCLUSION: We have demonstrated for the first time in vivo a significant decrease in the interaction of platelets and leucocytes with the endothelium in P-selectin-deficient mice with AiA and a reduction in clinical and histological symptoms of arthritis. These findings suggest that leucocyte-endothelial cell interactions depend at least partially on platelet P-selectin and therefore platelets may be responsible for the leucocyte tissue damage in AiA.


Subject(s)
Arthritis, Experimental/physiopathology , Blood Platelets/physiology , Endothelium, Vascular/physiopathology , Leukocytes/physiology , P-Selectin/physiology , Animals , Antigens , Arthritis, Experimental/blood , Arthritis, Experimental/pathology , Endothelium, Vascular/pathology , Female , Mice , Mice, Inbred C57BL , Microcirculation/physiology , Microscopy, Fluorescence
14.
Urologe A ; 46(9): 1112-7, 2007 Sep.
Article in German | MEDLINE | ID: mdl-17676299

ABSTRACT

OBJECTIVE: We determined if transrectal ultrasound (TRUS) is as reliable as cystography in detecting vesicourethral extravasates after radical retropubic prostatectomy (RRP). PATIENTS AND METHODS: Between October 2005 and February 2006 we prospectively investigated 100 consecutive patients undergoing RRP. The vesicourethral anastomosis was proven 6 days after operation by a combined investigation with TRUS and cystography. RESULTS: In the majority of patients (79%) the vesicourethral anastomosis was watertight on postoperative day 6 (POD) or showed minimal leakage (8%) so that the urinary catheter was removed. Different degrees of paravasates were detected in 21 patients. Because of small, moderate, or marked paravasations the indwelling catheter was removed on POD 9, 14, and 21 in 5, 3, and 5 patients, respectively. Every paravasate documented by cystography had been detected by TRUS before. Therefore, TRUS showed no false-negative result in detecting insufficient anastomosis. In two patients paraurethral fluid was detected by TRUS mimicking anastomotic paravasation, without confirmation by cystography. CONCLUSIONS: TRUS can safely replace cystography to detect anastomotic leakage after radical prostatectomy.


Subject(s)
Anastomosis, Surgical , Endosonography , Postoperative Complications/diagnosis , Prostatectomy , Surgical Wound Dehiscence/diagnosis , Urinary Bladder/diagnostic imaging , Aged , Catheters, Indwelling , Contrast Media/administration & dosage , Extravasation of Diagnostic and Therapeutic Materials/diagnosis , Humans , Male , Middle Aged , Polysaccharides , Predictive Value of Tests , Prospective Studies , Radiography , Urethra/surgery , Urinary Bladder/surgery
15.
Platelets ; 18(5): 365-72, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17654306

ABSTRACT

There is growing evidence that platelets play an important role in the development and maintenance of rheumatoid arthritis. Activation and adherence of platelets in the synovial microcirculation might be in part responsible for endothelial damage and activation of leukocytes. Recent findings show a direct influence of P-selectin on platelet- and leukocyte-endothelial cell interaction in mice with Antigen-induced Arthritis (AiA). P-selectin is only expressed by platelets and endothelial cells, not by leukocytes. Therefore, the aim of the present study was to investigate the differential influence of platelet and endothelial P-selectin on the extent of inflammation in AiA. AiA was induced in wild-type mice and in P-selectin-deficient mice from the same genetic background (four groups: each n = 7). Intravital fluorescence microscopy (IVM) was used to visualize platelets and leukocytes in the synovial microcirculation at day 8 after AiA. Platelets from either strain were fluorescence-labelled ex vivo and transferred into either strain. We were able to demonstrate a significant decrease of platelet- and leukocyte-endothelial cell interaction in P-selectin-deficient mice with AiA in comparison to wild-type mice with AiA. When wild-type platelets were donated into P-selectin-deficient AiA recipients, the leukocyte-endothelial cell interaction was significantly increased compared to the group consisting of P-selectin-deficient recipient and donor mice. These are the first in vivo results showing that the P-selectin stored in platelets is at least partly responsible for the leukocyte-endothelial cell interaction and the resulting tissue damage in AiA. In the future, a suppression of platelet P-selectin could potentially become a treatment option for reducing the effects of rheumatoid arthritis.


Subject(s)
Arthritis, Experimental/immunology , Arthritis, Rheumatoid/immunology , Blood Platelets/immunology , Cell Communication/immunology , Endothelial Cells/immunology , Leukocytes/immunology , P-Selectin/immunology , Animals , Antigens/toxicity , Arthritis, Experimental/chemically induced , Arthritis, Experimental/genetics , Arthritis, Experimental/pathology , Arthritis, Experimental/therapy , Arthritis, Rheumatoid/chemically induced , Arthritis, Rheumatoid/genetics , Arthritis, Rheumatoid/pathology , Arthritis, Rheumatoid/therapy , Blood Platelets/pathology , Cell Adhesion/immunology , Cell Communication/genetics , Endothelial Cells/pathology , Female , Leukocytes/pathology , Mice , Mice, Knockout , P-Selectin/genetics , Platelet Adhesiveness/genetics , Platelet Adhesiveness/immunology , Platelet Transfusion , Synovial Membrane/immunology , Synovial Membrane/pathology
16.
Inflamm Res ; 56(6): 262-8, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17607551

ABSTRACT

OBJECTIVE: Since an increase of platelet-endothelial cell interactions has been observed in mice with Antigen- induced-Arthritis (AiA) as well as an increase of NO expression, the aim of our study was to investigate in vivo the influence of NO, especially the platelet and endothelial inducible NO Synthase, on the platelet- and leukocyte endothelial cell interaction. MATERIAL AND METHODS: C57/Bl6 mice and iNOS deficient mice were disposed in 6 groups (each=7). After induction of AiA, rolling and adherent fluorescence labelled platelets and leukocytes were investigated by intravital microscopy (IVM) on day 8 after AiA. Rank SUM Test and ANOVA on ranks have been performed regarding the data. RESULTS: All arthritic mice presented an increase in platelet and leukocyte interaction with the endothelium compared to control groups. The arthritic iNOS deficient mice showed a more intense interaction of platelets and leukocytes with the endothelium in comparison with the wild-type arthritic mice. The group using arthritic wild-type recipient and iNOS deficient donor mice showed an increase in cell-interactions, leading to an endothelial effect, compared to the group using iNOS deficient arthritic recipient and wild-type donor mice. CONCLUSION: The IVM data lead to an anti-inflammatory effect of NO, since NO followed an increase in platelet- and leukocyte- endothelial cell interaction in iNOS deficient mice with AiA. In addition, we have shown for the first time in vivo that platelet NO produced by iNOS seems to have a minor influence on the leukocyte induced tissue damage in contrast to endothelial iNOS. Therefore, selective platelet inhibition would not interfere with the protective effect of NO.


Subject(s)
Arthritis/chemically induced , Blood Platelets/enzymology , Endothelium/enzymology , Leukocytes/enzymology , Nitric Oxide Synthase Type II/biosynthesis , Animals , Antigens/chemistry , Blood Platelets/metabolism , Endothelial Cells/metabolism , Mice , Mice, Inbred C57BL , Microcirculation , Microscopy , Microscopy, Fluorescence , Models, Statistical , Time Factors
17.
Rheumatology (Oxford) ; 44(7): 885-9, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15827038

ABSTRACT

OBJECTIVES: Growing evidence supports the substantial pathophysiological impact of platelets on the development of rheumatoid arthritis. At present there are no methods for studying these cellular mechanisms in vivo. The aim of this study was to visualize and investigate platelet-endothelial cell interaction in the knee joint of mice with antigen-induced arthritis (AiA) by means of intravital microscopy. METHODS: In 14 mice (Balbc) intravital microscopic assessment was performed on day 8 after AiA induction in two groups (controls, AiA). The severity of AiA was assessed by measuring knee joint swelling and by histological scoring. Ex vivo fluorescently labelled rolling and adherent platelets and leucocyte-endothelium interactions were investigated by intravital fluorescence microscopy. RESULTS: Swelling of the knee joint as well as histological score was significantly enhanced in arthritic animals compared with controls. In control mice intravital microscopy revealed low baseline rolling and sticking of leucocytes and fluorescently labelled platelets. AiA induced a significant increase in the fraction of rolling leucocytes (3 times) and rolling platelets (6 times) compared to the control group. Furthermore, AiA induction resulted in a significantly enhanced number of adherent leucocytes (3-fold) and adherent platelets (12-fold) in comparison with control animals. CONCLUSIONS: Platelet kinetics were directly analysed using intravital microscopy in the arthritic microcirculation in vivo for the first time. We provide the first evidence that platelets accumulate in arthritic vessels, indicating platelet activation due to AiA. Platelet recruitment and subsequent activation might play an important role in the pathogenesis of rheumatoid arthritis.


Subject(s)
Arthritis, Experimental/blood , Blood Platelets/physiology , Endothelium, Vascular/pathology , Animals , Arthritis, Experimental/pathology , Cell Communication , Female , Leukocytes/physiology , Mice , Mice, Inbred BALB C , Microcirculation , Microscopy, Fluorescence , Platelet Activation , Platelet Adhesiveness
18.
J Antimicrob Chemother ; 54(4): 824-7, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15317744

ABSTRACT

OBJECTIVES: Early studies have indicated that pamamycins, a group of macrodiolides first isolated from Streptomyces alboniger, have potent antimicrobial activity against Gram-positive bacteria, fungi and mycobacteria but not against Gram-negative bacteria. The recent availability of highly purified and reasonable quantities of several pamamycins through their total syntheses has rendered possible more extensive studies on their effects on mycobacteria. METHODS: Bioluminescent strains of Mycobacterium tuberculosis, Mycobacterium bovis BCG and Mycobacterium smegmatis, expressing the luxA and luxB genes from Vibrio harveyi were used for the comparison of the antimycobacterial activity of the two synthetic macrodiolides pamamycin-607 and pamamycin-621A and a non-naturally occurring cyclic dimer of pamamycin-607, i.e. yukomycin. RESULTS: Pamamycin-607 was the most active of the three macrocycles and was more active against M. tuberculosis than against M. smegmatis. Twenty-five clinical isolates of M. tuberculosis were susceptible to pamamycin-607 in a narrow MIC range of 1.5-2.0 mg/L. The new assay was also validated by comparison with the BACTEC radiometric test. CONCLUSION: Rapid screening of a new class of macrocyclic antimycobacterials using bioluminescent mycobacteria identified pamamycin-607 as a potential antituberculous agent. The latter was active against clinical isolates of M. tuberculosis within a narrow MIC range of 1.5-2.0 mg/L irrespective of their resistance to isoniazid or rifampicin. Our findings warrant further investigations.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Mycobacterium bovis/drug effects , Mycobacterium tuberculosis/drug effects , Anti-Bacterial Agents/chemistry , Antifungal Agents/chemistry , Luminescent Measurements , Macrolides , Microbial Sensitivity Tests , Molecular Structure , Organic Chemicals
19.
Phys Rev Lett ; 87(21): 214501, 2001 Nov 19.
Article in English | MEDLINE | ID: mdl-11736341

ABSTRACT

We have developed a new experimental technique to measure the Lagrangian velocity of tracer particles in a turbulent flow, based on ultrasonic Doppler tracking. This method yields a direct access to the velocity of a single particle at a turbulent Reynolds number R(lambda) = 740, with two decades of time resolution, below the Lagrangian correlation time. We observe that the Lagrangian velocity spectrum has a Lorentzian form E(L)(omega) = u(2)(rms)T(L)/[1+(T(L)omega)(2)], in agreement with a Kolmogorov-like scaling in the inertial range. The probability density functions of the velocity time increments display an intermittency which is more pronounced than that of the corresponding Eulerian spatial increments.

20.
Plant Cell ; 11(10): 1853-66, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10521517

ABSTRACT

A modified Enhancer-Inhibitor transposon system was used to generate a series of mutant lines by single-seed descent such that multiple I insertions occurred per plant. The distribution of original insertions in the population was assessed by isolating transposon-flanking DNA, and a database of insertion sites was created. Approximately three-quarters of the identified insertion sites show similarity to sequences stored in public databases, which demonstrates the power of this regimen of insertional mutagenesis. To isolate insertions in specific genes, we developed three-dimensional pooling and polymerase chain reaction strategies that we then validated by identifying mutants for the regulator genes APETALA1 and SHOOT MERISTEMLESS. The system then was used to identify inserts in a class of uncharacterized genes involved in lipid biosynthesis; one such insertion conferred a fiddlehead mutant phenotype.


Subject(s)
Arabidopsis/genetics , DNA Transposable Elements , Enhancer Elements, Genetic/genetics , Genome, Plant , Repressor Proteins/genetics , Base Sequence , DNA Primers , Mutagenesis, Insertional , Polymerase Chain Reaction
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