Biomedical subjects

J Adler

Publications and source records attributed to J Adler.

At least 19 recordsLinked to original sources

PubMed2006

Simulated annealing in ocular adaptive optics.

We present what is to our knowledge a first hardware realization of a simulated annealing algorithm in an adaptive optics system designed to image the retina of the human eye. The algorithm is applied to the retinal image itself without the need for wavefront sensors in the system. We find that this optimization algorithm can be an alternative to the traditional Hartmann-Shack sensing. We also compare the simulated annealing algorithm to the stochastic parallel gradient descent algorithm.

Algorithms↗

PubMed2005

Esomeprazole 20 mg vs. pantoprazole 20 mg for maintenance therapy of healed erosive oesophagitis: results from the EXPO study.

BACKGROUND: Following initial healing of erosive oesophagitis, most patients require maintenance therapy to prevent relapse. AIM: To compare endoscopic and symptomatic remission rates over 6 months' maintenance therapy with esomeprazole or pantoprazole (both 20 mg once daily) in patients with healed erosive oesophagitis. METHODS: Patients with symptoms of gastro-oesophageal reflux disease and endoscopically confirmed erosive oesophagitis at baseline were randomized to receive esomeprazole 40 mg or pantoprazole 40 mg for up to 8 weeks. Patients with healed erosive oesophagitis and free of moderate/severe heartburn and acid regurgitation at 4 weeks or, if necessary, 8 weeks entered the 6-month maintenance therapy phase of the study. RESULTS: A total of 2766 patients (63% men; mean age 50 years) received esomeprazole 20 mg (n = 1377) or pantoprazole 20 mg (n = 1389) and comprised the intention-to-treat population. Following 6 months of treatment, the proportion of patients in endoscopic and symptomatic remission was significantly greater for those receiving esomeprazole 20 mg (87.0%) than pantoprazole 20 mg (74.9%, log-rank test P < 0.0001). Esomeprazole 20 mg produced a higher proportion of patients free of moderate to severe gastro-oesophageal reflux disease symptoms and fewer discontinuations because of symptoms than pantoprazole 20 mg (92.2% vs. 88.5%, P < 0.001). CONCLUSIONS: Esomeprazole 20 mg is more effective than pantoprazole 20 mg for maintenance therapy following initial healing of erosive oesophagitis and relief of gastro-oesophageal reflux disease symptoms.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2005

[Treatment of talar chondral lesions by solid chondral graft -- first experience].

The aim of this report is to draw attention to new possibilities of treating chondral lesions of the talus, using a solid chondral graft consisting of autologous chondrocytes grown on a three-dimensional matrix of the tissue glue Tissucol. This method is used in grade II to grade IV chronic lesions and grade IV acute lesions, as classified according to the Berndt and Harty system. Patients' age at implantation should not exceed 40 years. When a lesion is found by arthroscopy on the talar dome, a part of cartilage from a non-weight-bearing surface, most frequently the neck of the talus or the anterior edge of the tibia, is collected. The cartilage is sent to the tissue bank. The preparation of a chondral graft (fragmentation, isolation and cultivation of chondrocytes) takes from 15 to 35 days. After shaping the graft from chondrocytes and Tissucol tissue glue in a special mould, transplantation is carried out. In 2003 we used this method in two patients. They both were male sportsmen, football players, aged 35 and 30 years, respectively. At the time of this report, the former patient was 8 months and the latter 3 months after implantation. The first patient, aged 35, was without complaints at 8 months after implantation. The other patient, a 30-year-old football player, who was still followed up, was without complaints and continued with rehabilitation and full weight-bearing of the extremity. Magnetic resonance imaging performed 3 months post-operatively showed good incorporation of the chondral graft in both patients.

Adult↗

PubMed2004

Cryopreserved and lyophilized cultured epidermal allografts in the treatment of leg ulcers: a pilot study.

BACKGROUND: In the conservative therapy of venous leg ulcers modern types of dressings are used most frequently. In the past 20 years 'active wound dressings' - cultured epidermal keratinocytes as autografts and allografts - were also introduced in the management of leg ulcers. METHODS: The aim of our study was to compare the effect of cryopreserved and lyophilized cultured epidermal allografts in the treatment of venous leg ulcers. Evaluation of the therapy was documented as photodocumentation, planimetry, healing time and evaluation of pain relief over a 3-month period after application. Fifty patients with venous leg ulcers were selected. Twenty-five patients (group I) were treated with cryopreserved keratinocytes and 25 (group II) with lyophilized keratinocytes. RESULTS: The final evaluation 3 months after the application of allografts showed 84% of healed ulcers in group I and 80% in group II. The number of healed ulcers and the healing rate both showed no statistically significant differences. The size of the ulcer was reduced by half during the first week in both groups. The size differences during the first week are statistically significant in both groups and they are comparable (P < 0.001). The intensity of the pain was statistically significantly reduced during the first week after application in both groups (P < 0.001). CONCLUSIONS: The cryopreserved and lyophilized cultured allografts are comparable in healing rate, course of healing and relief of pain, and also in planimetric changes during the healing of venous leg ulcers. Lyophilized allografts are more convenient for routine use than cryopreserved allografts as they can be stored at room temperature. These results could give rise to the more frequent use of lyophilized allografts in slow-healing venous leg ulcers.

Adult↗

PubMed2004

[Treatment of patellar cartilage defects by solid chondral graft: first experience].

PURPOSE OF THE STUDY: To present the results of a new method for treatment of cartilage defects of the patella, using a solid graft produced by chondrocytes on a three-dimensional matrix. MATERIAL AND METHODS: Chondrocyte transplantation is indicated in deep and extensive chondral and osteochondral defects of all large joints in patients at 18 to 40 years of age. When, on arthroscopic examination, a defect of patellar cartilage was found, healthy cartilage was collected from a non-weight-bearing surface, i. e., the intercondyllar fossa. In the tissue bank, the cartilage was fragmented, chondrocytes were isolated enzymatically and cultivated in vitro under a permanent assessment for cell quality. The cultivation period ranged from 15 to 35 days. Subsequently, a solid graft was prepared with the use of Tissucol glue, a three-dimensional matrix. The graft was transplanted after arthroscopic verification of the defect by an open, minimally invasive procedure with tourniquet application, with the patient receiving antibiotics. The result of chondral graft implantation was checked by second-look arthroscopy involving removal of a small sample of the integrated chondral graft taken for histological and morphological examination. Another method of post-operative assessment was examination by magnetic resonance imaging (MRI). Solid chondral graft transplantation was used in three patients (two men and one women) treated in the Department of Orthopedics, University Hospital Brno, between May 2001 and December 2003. Their average age at the time of surgery was 31 years (range, 27 to 38 years). The average follow-up was 22 months (range, 2 to 33 months). The post-operative stage of he cartilage was assessed by MRI in one patient and by second-look arthroscopy also in one patient. RESULTS: Two patients fully resumed their daily activities, sports including, at 6 months after the treatment, with one reporting mild chondropathic problems and the other being without complaints. In the third patient at 2 months after surgery, the treatment had not been completed yet. The patella examined by MRI at 18 months after surgery showed a confluent, high layer of hyaline cartilage covering the articular surface. Second-look arthroscopy and histological examination also revealed healthy hyaline cartilage. No serious complications were recorded. DISCUSSION: Autologous chondrocyte transplantation is indicated in younger, active patients with cartilage defects exceeding 2 cm2 and in patients undergoing revision surgery for any defect. The success rate of this procedure has been reported to be over 90 %. One year after transplantation, the cartilage had characteristics of a healthy tissue, as assessed by MRI. Biopsy examination showed that the grafts, chondrocytes as well as osteocytes maintained their integrity at 2 to 12 months after surgery. CONCLUSIONS: The aim of this paper was to define and check indications, to develop the surgical technique, to improve post-operative management and to evaluate mid-term results of the treatment of cartilage defects on the patella.

Adolescent↗

PubMed2004

Successful treatment of chronic venous leg ulcers with lyophilized cultured epidermal allografts.

The case of a 67-year-old woman with chronic venous leg ulcers and severe gonarthrosis is described. In spite of intensive therapy, the leg ulcers had persisted for 4 years and made the intended orthopaedic operation of the right knee impossible. The patient was treated with lyophilized cultured epidermal allografts and her leg ulcers healed within 40 days. Lyophilized cultured epidermal allografts represent a modern type of active wound dressing that leads to rapid healing of chronic venous leg ulcers and enables patients to undergo surgical intervention.

Journal Article↗

PubMed2003

Reducing image distortions due to temperature-related microscope stage drift.

Distortions in confocal 3D image data sets were related to movements of the microscope stage that matched fluctuations in laboratory temperature. Movement was apparent in all three axes. Adding a draught-proof enclosure, covering the stage, objective lenses and supporting structures, minimized these short-term fluctuations. However, the stage still tracked slow changes in laboratory temperature and was sensitive to heat sources mounted on the microscope. Suggestions are made about microscope design.

Image Enhancement↗

PubMed2003

[Bone grafts in hip prosthesis revisions].

PURPOSE OF THE STUDY: We describe the collection, storage and examination of allogenic bone grafts and their use in revision hip arthroplasty, indicated because of acetabular loosening, that involved either an uncemented cup or an augmentation device with a cemented cup according to the extent and nature of acetabular defects. MATERIAL: Allogenic bone grafts, usually long bones, were collected from deceased humans within 12 hours of death. They were processed according to the standards of US tissue banks. Using ELISA, the blood of each donor was serologically examined for antibodies against selected antigens (HIV I, HIV II, syphilis, HbsAg, HCV, and p24HIV I, HTLV I and II, and HbcAg, if required). Microbiological examination of each bone sample was also included. The samples were kept in a quarantine box until the examination results were known. When these were negative, the bones were cut, under aseptic conditions, to obtain parts (condyle, metaphysis, diaphysis, patella, etc.) weighing from 80 to 150 gr. Subsequently, another quality check, involving microbiological and histological examination, was performed. The allografts were stored at -80 degrees C. METHODS: Between October 1999 and October 2000, 67 revision total hip replacements were performed. Of these, allogenic bone grafting was used for acetabular reconstruction in 30 cases (45%). The average amount of graft tissue per operation was 107 gr (range, 43 to 163 gr). Eleven grafts had been harvested from the tibial condyle, nine from the trochanters, eight from the femoral condyle and two from the patella. The graft bone, ground into coarse chips, was washed with an antibiotic solution. Two techniques were used in graft implantation. 1) Impaction grafting, under pressure, of the acetabulum whose surface was free from any granulation tissue and scratched to make the bone bleed, and implantation of a cemented cup (LOR or Spotorno CLS). 2) Filling of large defects with a bulk of allograft bone chips, using an augmentation ring, mesh or Burch-Schneider cage, and implantation of a cemented polyethylene acetabular component. Uncemented implants were used in 17 and cemented cups with an augmentation device in 13 cases. The hips were checked by X-ray at 3, 6 and 12 months and then at yearly intervals. RESULTS: In the postoperative period of 26 to 38 months, an early recurrent infection led to temporary removal of the implant in one case, one hip showed superficial infection that responded to therapy and there was one case of aseptic acetabular loosening. A recurrent dislocation led to femoral stem exchange for a modular component with a longer neck in one case. The remaining 28 cases showed good incorporation of the graft without any signs of implant migration. DISCUSSION: Segmental defects of the acetabulum can be treated by implantation of specific types of acetabular cups or by massive bone grafting. Cavitary defects can be filled with cancellous allograft bone or bioactive, artificial materials. We prefer morselized allograft bone from the tissue bank and this was used in 45% of repeat surgeries for failure of the acetabular component. An uncemented cup is more convenient, supposing sufficient primary stability can be ensured. When defects are extensive, augmentation devices and filling with graft bone are necessary. Cadaver allografts offer advantages over autologous bone because they are available at any amount and thus enable us to avoid extensive damage to the iliac crest by autologous tissue harvesting. Cadaver grafts are bones of good quality, free from degenerative or dystrophic changes because they are usually taken from young subjects. The size of 7 to 10 mm is optimal because it permits the grafts to maintain both structure and strength. The strict procedure of sample collection and examination minimizes the risk of infection transfer. The progress of graft bone ingrowth was evaluated on radiographs that showed incorporation of allograft into the surrounding bone during 3 to 6 months and no radiolucent areas at host bone-implant contact. CONCLUSIONS: Our patients showed good allogenic bone ingrowth in relation to the acetabular bed and good bone restructuring and incorporation in relation to the implant. Neither mechanical failure of implants nor graft rejection were recorded. The risk of infection transfer was low and comparable with routine blood transfusion. The necessary prerequisite for revision hip arthroplasty is a well-operating bone tissue bank.

Acetabulum↗

PubMed2003

[Treatment of deep chondral defects of the knee using autologous chondrocytes cultured on a support--preparation of the cartilage graft].

PURPOSE OF THE STUDY: Chondral and osteochondral defects represent an important topic in the knee surgery. The knee traumas are often followed by premature development of osteoarthritis due to limited reparative processes in the cartilage. Today's diagnostic possibilities and progress in arthroscopic techniques promote the early diagnostics and exact classification of osteochondral defects. Authors present therapeutic ways for treatment of cartilage injuries and adjacent part of the subchondral bone. New possible method for treatment of deep chondral defects on the weight-bearing area of the knee is the application of autologous cultivated chondrocytes in Tissucol (Baxter, Austria). MATERIAL AND METHODS: Chondrocyte retrieval and in vitro cultivation is today a commonly known method. The goal of the knee surgery is to find a suitable three-dimensional bearer for chondrocyte culture. After serial laboratory tests we decided to use the tissue fibrin glue Tissucol (Baxter, Austria) as a chondrocyte carrier. Very good cell viability and capability of cell migration and outgrow in Tissucol were documented. Authors describe a new chondrograft type, its characteristics. They focused on quality control and documentation of key parameters necessary for graft use in humans. Following methods for quality control were used: Sterility control Determination of cells number Determination of cell viability by trypan blue staining. Viability between 90-95% was demonstrated. Determination of proliferative activity was tested using growth quality control. Migration and outgrowth of chondrocytes was documented. The morphological characteristics were studied by: Light microscopy (haematoxylin-eosin staining). Electron microscopy (transmission and scanning). A good stage of cellular organelles and production of extracellular matrix with protocollagenic fibrils were found in all cases. Immuno-fluorescence microscopy (using monoclonal antibodies against vimentin). RESULTS: Preclinical testing on pigs and cadaverous was provided following laboratory investigations. Testing on cadaverous demonstrated a chondrograft ability to fill up completely the chondral defect to renovate the anatomic surface of the joint cartilage. Tests on pigs described hyaline-like cartilage. Publication contains detailed description of chondrograft preparation to allow reproducibility of described technique. Chondrograft transplantation consists of following phases: Arthroscopic diagnostic of defect. Arthroscopic sampling of cartilage for in vitro cultivation. Transport of samples to tissue bank. Enzymatic isolation, in vitro cultivation of chondrocytes. Graft formation (combination of fibrin glue Tissucol with chodrocytes), quality control. Transplantation (chondrograft agglutination into defect). DISCUSSION: The goal of the nowadays tissue engineering is to find an optimal three-dimensional carrier for autologous chondrocyte culture. A new type of carrier based on hyaluronic acid--Hyalograft C was presented by Marcani et al in 2001 year. Published results from the first 20 clinical cases using Hyalograft C do not report any method complications. Our chondrograft technique represents an alternative option when compared to method described by Marcani. CONCLUSIONS: Based on the successful preclinical outcomes observed in this study, authors conclude that autologous chondrocyte transplantation in Tissucol offers an important treatment option for large full thickness chondral lesions located on the weight-bearing surfaces of the femur.

Cartilage, Articular↗

PubMed2003

[Treatment of deep chondral defects of the knee using autologous chondrocytes cultured on a support--results after one year].

PURPOSE OF THE STUDY: The treatment of deep chondral defects is one of the key issues in current orthopedics and traumatology. We developed a new technique that greatly improved the outcome of treatment in young active patients. The method is based on transplantation of in vitro cultured autologous chondrocytes carried on the fibrin glue Tissucol. MATERIAL: In the years 2000 to 2002, 19 patients with deep chondral defects were treated by chondrocyte transplantation with the use of Tissucol. At 1 year, 14 defects (average size, 4.31 cm2; range, 2.0 to 10.0 cm2) in 12 patients were evaluated. The defects were localized on the weight-bearing areas of the femoral condyle, tibial plateau and femoropatellar joint in 10, one and three patients, respectively. METHODS: The Lysholm knee score and IKDC subjective score were used for outcome evaluation. Second-look arthroscopy and repair assessment, on the basis of ICRS, were carried out in four patients. RESULTS: The patients were examined at 5 and 12 months after surgery. The average value of the Lysholm knee score before surgery was 45.6 points and those at 5 and 12 months after surgery were 72.0 points and 81.5 points, respectively. Good or excellent outcomes were achieved in seven patients. The average preoperative IKDC subjective score was 39.0 points and the postoperative values were 60.0 and 71.2 points at 5 and 12 months, respectively. Second-look arthroscopy was performed in four patients at 3 to 5 months after the transplantation. A very good, complete healing of the graft was observed in two patients and partial chondrograft degeneration (30% graft area) was seen in two patients. The graft surfaces were evaluated according to the cartilage repair assessments system (ICSR-cartilage score) and the average value obtained was 8.5 points, i.e., almost a normal graft surface. During the second-look arthroscopy, samples for examination by light and electron microscopy were collected. In the healing defects, they showed the presence of hyaline-like cartilage characterized by typical spherical chondrocytes, extracellular collagenous filaments and formation of typical isogenetic cell groups. In the regions of graft degeneration (fissuration), neovascularization of the issue with the presence of fibroblast-like cells was recorded. DISCUSSION: Excellent and very good outcomes were observed in 58% of our patients. Similar studies reported excellent and good results in 80 to 85% of the patients. On comparison, our group included more serious cases with the high presence of severe concomitant injuries, which influenced the final outcome. However, improvement was achieved in all 12 evaluated patients. CONCLUSIONS: The method described is effective for treating deep chondral knee injuries and can be recommended for use in clinical practice.

Adult↗

PubMed2002

Cultured epidermal allografts: Quantitative evaluation of their healing effect in deep dermal burns.

This study summarizes the Brno Burn Centre experience with the application of cultured epidermal allografts (CEAl) in the treatment of deep dermal burns. In a prospective randomised trial on 30 patients with deep dermal burns CEAl obtained from young healthy and examined donors and fixed on tulle grass carrier (Grasolind) were compared with empty Grasolind as the lowest layer of dressing. All the other layers were identical.Both kinds of dressing were applied simultaneously on the same deep dermal burn wound between 6th and 10th day after burn. Six days later the non-healed wound areas were recorded through painting on cellophane membrane and scanned in the computer. The percentage of wound reduction was calculated and statistically evaluated.The reduction of the non-epithelialized wound area was 86.5% when covered through CEAl and only 71.2% when covered with tulle grass (Grasolind) only. This difference is statistically significant.In conclusion it can be stated that cultured epidermal allografts strongly stimulate reepithelialisation in deep dermal burns.

Journal Article↗

PubMed2002

Interleukin-2 activation of haematopoietic stem cells.

BACKGROUND: Recent findings concerning the role of immunity in the eradication of residual malignant disease after autologous haematopoietic stem cell transplantation have led to extensive studies of T-cell and natural killer (NK) mediated anti-tumour effects. Interleukin 2 (IL-2) activation of autologous bone marrow (BM) or peripheral blood stem cells (PBSC) before transplantation is one of the methods of adoptive cell therapy. METHODS: Autologous BM of patients with chronic myelogenous leukaemia (n = 11) and PBSC of patients with multiple myeloma (n = 14) were activated by IL-2 in laboratory conditions with the aim of evaluating the feasibility of this method, the activation of T and NK cells, recovery of active progenitor cells, microbial contamination, and reduction of malignant cell content. RESULTS: Samples of BM (mean 2.6 x 10(6) cells) and PBSC (mean 10.3 x 10(6) cells) were cultured in complete culture medium with IL-2 (6000 Ul/ml) for 24 h. The recovery of CD34+ cells and CFU-GM was 82.5% and 51.5%, respectively, for BM, and 85% and 86%, respectively, for PBSC (mean values). No purging effect was detected by flow cytometry and a small decline in malignant cell contamination was observed by quantitative PCR in BM samples. No microbial contamination occurred during the sample processing. CONCLUSIONS: The described in vitro activation of BM and peripheral blood stem cells using IL-2 was evaluated as a safe and reliable method suitable for clinical application.

Bone Marrow↗

PubMed2001