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H Merk

Publications and source records attributed to H Merk.

At least 19 recordsLinked to original sources
PubMed2004

Delayed remodeling in the early period of fracture healing in spontaneously diabetic BB/OK rats depending on the diabetic metabolic state.

Several clinical series, analyzing fracture healing in patients with insulin-dependent type 1 diabetes (IDDM) demonstrated significant incidence of delayed union, non-union, and pseudarthrosis. The purpose of this study was to examine the detailed histomorphometry and histology of bone formation and remodeling during fracture healing depending on the diabetic metabolic state in spontaneously diabetic BB/O(ttawa)K(arlsburg) rats, a rat strain that represents a close homology to IDDM in man. A standardized fracture model was chosen and based on blood-glucose values at the time of surgery (mg%), postoperative blood-glucose course (mg%) and postoperative insulin requirements (IU/kg), 100 spontaneously diabetic BB/OK rats were divided into groups with well-compensated (n=50, 167+/-77 mg%; 244+/-68 mg%; 1.8+/-1.9 IU/kg) or poorly compensated (n=50, 380+/-89 mg%; 415+/-80 mg%; 6.0+/-1.0 IU/kg) metabolic state. Fifty LEW.1A rats served as the normoglycemic controls (97+/-15 mg%). Ten animals from each group were killed 1, 2, 3, 4 and 6 weeks after fracture and specimens were processed undecalcified for quantitative histomorphometry and for qualitative light microscopy. In terms of bone histomorphometry, within the first four weeks after fracture, severe mineralization disorders occurred exclusively in the rats with poorly compensated diabetic metabolic states with a significantly decrease of all fluorochrome-based parameters of mineralization, apposition, formation and timing of mineralization in comparison to the spontaneously diabetic rats with well-compensated metabolic states and to the control rats. This was confirmed histologically. Early fracture healing in the spontaneously diabetic BB/OK rats is delayed exclusively in poorly compensated diabetic metabolic states, and 6 weeks after fracture, histomorphometrically significant deficits in the measured and dynamically calculated parameters remain. This study suggests that strictly controlled insulin treatment resulting in well-compensated diabetic metabolic states will ameliorate the impaired early mineralization and cell differentiation disorders of IDDM fracture healing.

Animals↗
PubMed2003

[Experiences after 150 cartilage-bone-transplantations of the knee: a prospective analysis of the results].

INTRODUCTION: To evaluate the clinical outcome of cartilage-bone-transplantations of the knee in patients with different indications, we studied the clinical results of 45 patients with a follow-up of 24 months after operation. PATIENTS AND METHODS: 29 male and 16 female patients with a mean age of 37.7 yrs (16-58 yrs) were included. Indications for operation were osteochondritis dissecans (OD) (n=13), limited arthritis (n=20), traumatic lesions (n=5) and retropatellar lesions (n=7). The results were evaluated by clinical score (McDermott Score; preoperatively, and 3, 6, 12, 24 months postoperatively), magnetic resonance imaging, and re-arthroscopy for most patients. RESULTS: 42 of 45 patients judged the operation as successful. The mean score value of all patients raised from 66.3 pts (out of 100 pts) preoperatively to 92.7 pts 24 months postoperatively. The results of the patients with circumscript arthritic lesions (62.9 pts. preoperatively vs. 91.5 pts. postoperatively) were comparable to those of the other patients. CONCLUSION: We conclude that cartilage-bone-transplantation of the knee is a valuable procedure to improve joint function not only after OD or trauma, but also in joints with local arthritic lesions on condition that there is an adequate quality of the donor site.

Adolescent↗
PubMed2003

Scanning electron microscopic examinations on retarded bone defect healing in spontaneously diabetic BB/O(ttawa)K(arlsburg) rats.

To date, no detailed knowledge from animal experiments is available on the kind and extent of osseous and mineral metabolic disorders in genetically determined, insulin-dependent Type I diabetes. The purpose of this study was to examine the influence of the diabetic metabolic state in spontaneously diabetic BB/O(ttawa)K(arlsburg) rats on bone defect healing. Eighty spontaneously-diabetic BB/OK rats with a blood-glucose value of 391 +/- 106 mg% (mean +/- SD) at the time of manifestation were used in the study. Based on blood-glucose values at the time of surgery (mg%), postoperative blood-glucose course (mg%) and postoperative insulin requirements (IU/kg), the animals were divided into groups with well-compensated (n = 40, 170 +/- 101 mg%; 221 +/- 120 mg%; 2.1 +/- 1 IU/kg) or poorly compensated (n = 40; 371 +/- 158 mg%; 357 +/- 83 mg%; 5.2 +/- 1.4 IU/kg) metabolic state. Forty LEW.1A rats served as the normoglycemic controls (95 +/- 18 mg%). Using a 1-mm-diameter Kirschner wire, a hole of femoral bone ca. 1 cm proximal to the knee joint space was centrally drilled. Ten animals from each group were killed on postoperative days 7, 14, 24, and 42, and specimens were taken for analysis. Using SEM to measure regions of new bone semiautomatically and quantitatively, also determining the number, area, and circumference of regions not yet filled with new bone. Up to postoperative day 14, very significant differences (p < 0.0001) for all investigated characteristics were found between the spontaneously-diabetic BB/OK rats and the control animals--in favor of the controls--and up to postoperative day 24 within the group of spontaneously-diabetic BB/OK rats, where the well-compensated animals had significantly better results in terms of number and area of regions of bone not yet filled with new bone formations. Forty-two days postoperatively, SEM observations showed no differences between examination groups. The process of bone defect healing in spontaneously-diabetic rats was disturbed only in the early phase and exhibited retardation in its progression. After 42 days, bone defect healing was complete, regardless of the diabetic metabolic state; no differences were detected with the SEM between examination groups at this time point.

Animals↗
PubMed2002

[Sensitivity and significance of nuclear magnetic tomography findings of finger joints in rheumatoid arthritis].

Evaluation of the sensitivity and value of magnetic resonance imaging (MRI) findings and miniarthroscopic investigations (mini-/needle-arthroscopy = MA) of metacarpophalangeal (MCP) joints in patients with rheumatoid arthritis (RA). 30 patients with RA (21 female, 9 male), disease duration 2 months to 22 years and mean disease activity score (DAS) of 3.90 (range: 2.00-7.67) were examined by MRI of the hand (MCP region) and following MA of the MCP-II joints. MRI parameters for arthritis (synovial enhancement, synovial extension, cortical alterations, joint gap width) and corresponding macroscopic items (synovial extension, synovial hyperemia and vascularity, cortical alterations) by MA, scored semiquantitatively for synovitis (graduated from 0-III degree), were correlated. Additionally, normal radiographs of the hands were performed and compared with MRI findings concerning the detection of bony lesions. Evaluation of the 30 MRI and MA examination revealed highly significant correlations (p < 0.0001) for the parameters of synovial extension (MRI/MA), cortical alterations (MRI/MA) and synovial enhancement (MRI) compared to synovial hyperemia and vascularity (MA). We found significant correlations for parameters of activity and chronicity of RA pathology as assessed by MRI and MA. The detection rate of cortical lesions by MRI was two and a half times higher than by X-ray. MRI findings of MCP-II joints compared to those of MCP III-V showed that the MCP-II joint was more strongly involved.

Adult↗
PubMed2002

When should a substance be designated as sensitizing for the skin ('Sh') or for the airways ('Sa')?

In the List of MAK and BAT Values compounds are designated with 'Sa' ('sensitizing for the airways') or 'Sh' ('sensitizing for the skin') if, according to scientific evidence, they are allergens. Mainly based on suggestions by a WHO working group and based on our own experience, extended criteria have been elaborated by the working group 'skin and allergy' of the Commission of the Deutsche Forschungsgemeinschaft for the Investigation of Health Hazards of Chemical Compounds in the Work Area, which are presented in this article. They serve as guidelines for deciding which substances have to be labelled 'Sa' and 'Sh', respectively, for the prevention of sensitization and subsequent allergic diseases in workers. Although in some special cases their strict application may not be deemed necessary or possible, the proposed new criteria should be used to make the procedure of classification of substances: 1) more rational, 2) more consistent, 3) more comprehensible, and 4) more transparent. This paper informs readers working scientifically or administratively in this field and invites a critical discussion of the issue.

Allergens↗
PubMed2001

[Comparison of 2 surgical techniques in isolated supraspinatus rupture. A matched-pair study].

The comparison of results after open surgery methods in the repair of rotator cuff ruptures needs homogen patient groups. We compared 34 patients in 2 groups who were treated with open surgery for isolated ruptures of the supraspinatus muscles (lesion type III). Patients in group I were treated with transosseous suture refixation of the supraspinatus, in group II suture anchors (type: Corkscrew) were used. Both groups were age and gender paired. Preoperatively, all patients had the same clinical status. For the evaluation of the clinical results at follow-up we used the Constant-Score. In addition, strength and pain measurement and oblique X-rays of the shoulder were performed. The follow-up time was 18 months. In all patients, the mean Constant-Score improved significantly with increase in muscle strength and marked pain reduction. Significant differences between both groups could not be observed. The mean time of surgery in group II (suture anchor) was significantly lower than in group I. In conclusion, with the anchor techniques the same good results can be achieved as with bone refixation. The shortening of the surgery time should, however, be seen in relation to the higher costs with this technique.

Adult↗
PubMed2001

Management of urticaria: a consensus report.

This consensus report is the result of a panel discussion during the International Clinically Oriented ESDR Symposium Urticaria 2000. Urticaria has a profound impact on the quality of life and effective treatment is required. The most important are nonsedating H1 antihistamines. They have been proven to be effective in double-blind controlled studies, but concentrations higher than those recommended may be necessary. Due to different urticaria subtypes and the individual variation in the course of the disease and response to treatment, however, alternative therapies may be required. Immunosuppressive drugs like cyclosporine A and corticosteroids should not be used long term due to undesirable side-effects.

Adrenal Cortex Hormones↗
PubMed2001

[Calcifications after operations of the subacromial space].

OBJECTIVE: Although there are several studies on the development of periarticular calcifications after different operation procedures of the joints, such calcifications have only seldomly been described in connection with operations in the subacromial space. Therefore, the present study was aimed at investigating the incidence of periarticular calcifications after operations in the subacromial space and to assess their clinical relevance. PATIENTS AND METHODS: In a retrospective study we examined 152 patients (51 female, 101 male) who had been operated on for primary shoulder impingement by open or arthroscopic procedures. The average follow-up time was 32.5 months. The assessment of the outcome of the treatment was performed using the criteria of the Constant score, different shoulder tests, a visual-analog scale for the evaluation of pain, and by evaluation of radiographs. RESULTS: Our study revealed good clinical results in the operative treatment of different stages of primary shoulder impingement and thus confirmed the results of similar studies before. However, in 25.6% of all patients we found periarticular calcifications. Hereby, calcifications occurred significantly more often after open procedures (56.8%) than after arthroscopic procedures (12.9%). There was non correlation between the occurrence of such calcifications and the stage of the disease. Moreover, comparison of the clinical results and the Constant scores at follow-up did not reveal any differences between patients with and without periarticular calcifications. CONCLUSION: Our study shows that the presence of periarticular calcifications after operations in the subacromial space is not necessarily associated with clinical symptoms. Therefore, routine prophylactic measurements against such calcifications are not justified.

Acromioclavicular Joint↗
PubMed2001

[Recurrent luxations after arthroscopic refixation of the labrum using suture anchors in traumatic ventral shoulder luxation].

OBJECTIVE: Recurrence rates after arthroscopic labral reconstruction for anterior shoulder instability are still higher than after open procedures. Therefore, proper selection of patients becomes increasingly important. The aim of this study was to investigate factors influencing recurrence rates after arthroscopic labral repair with suture anchors. PATIENTS AND METHODS: We examined 53 patients (43 male, 10 female) with traumatic anterior shoulder dislocations, who were treated with arthroscopic labral repair using Fastak-Suture anchors between 1995 and 1996. The average follow-up time was 18 (12-30) months. The mean age of the patients at the time of operation was 27 (15-44) years. RESULTS: Postoperatively, 11 patients (20.7%) reported on redislocations. Recurrence rates increased significantly in patients with more than 4 preoperative dislocations and in patients with bony Bankart lesions. In patients without redislocations, the mean Rowe score improved from 65.9 (SD +/- 12.3) preoperatively to 88.6 (SD +/- 12.5) at follow-up. Thus, there were 24 excellent, 9 good and 6 fair results, while in 3 patients with persisting signs of shoulder instability results had to be estimated as poor. Deficits in the range of motion of more than 15 degrees were seen in 7 patients with predominant affection of the external rotation. CONCLUSION: Frequent preoperative dislocations and bony Bankart lesions contribute substantially to high recurrence rates after arthroscopic labral repair. Therefore, in these cases open procedures should be preferred.

Adolescent↗
PubMed2001

[Ultrasonography of the Osgood-Schlatter disease].

AIM: The aim of our study was to asses the value of ultrasound in the diagnosis of M. Osgood-Schlatter. The results of the primary ultrasound examination were compared with the use of X-ray. METHOD: 15 patients were included in our study (average age 11 - 17 years, 8 female, 7male). All patients get an X-ray of the knee in two or three images. There was a reference-group of 10 patients with 20 joints (average age 11 - 14 years). RESULTS: We observed typical sonographic images in different stages of M. Osgood-Schlatter. The changes depended on the duration of the disease. In every case we found a thickness of the patellar tendon of more than 1 mm (stage I and II), a bursitis infrapatellaris (stage II) and a fragmentation of the cortical bone of the apophysis (stage II). In cases of stage III disease a thickness of the patellar tendon of less than 1 mm was to be seen. In healthy people the average thickness of the patella tendon was 4.8 mm (3.5 - 5.7 mm). The maximal difference between the left and the right side was 0.4 mm. CONCLUSIONS: With the use ultrasound in cases of M. Osgood-Schlatter a reduced exposure of children to X-ray is possible. Ultrasound examination is a clear and easy way to diagnose the disease correctly and evaluate its course and cure.

Adolescent↗
PubMed2000

Photodynamic therapy in dermatology.

UNLABELLED: The combination of light and chemicals to treat skin diseases is widely practiced in dermatology. Within this broad use of light and drugs, in recent years the concept of photodynamic therapy (PDT) has emerged. PDT is a promising modality for the management of various tumors and nonmalignant diseases, based on the combination of a photosensitizer that is selectively localized in the target tissue and illumination of the lesion with visible light, resulting in photodamage and subsequent cell death. Moreover, the fluorescence of photosensitizing compounds is also utilized as a helpful diagnostic tool for the detection of neoplastic tissue. Intensive basic and clinical research culminated in the worldwide approval of PDT for bladder, esophageal, and lung cancer. The expanding use of this relatively new therapeutic modality in dermatology at many centers around the world has revealed its efficacy for the treatment of cutaneous precancer and cancer, as well as selected benign skin disorders. The following article summarizes the main principles of PDT considering the most recent developments and provides a comprehensive synopsis of the present status of the use of PDT in dermatology. (J Am Acad Dermatol 2000;42:389-413.) LEARNING OBJECTIVE: At the conclusion of this learning activity, participants should be able to describe the basic concepts of PDT, including fundamental knowledge of the most relevant photosensitizers, the light sources, the mechanisms involved in PDT-mediated cell destruction, as well as the indications and limitations of photodynamic treatment of skin diseases.

Dermatology↗
PubMed2000

Multicentre study for the development of an in vivo model to evaluate the influence of topical formulations on irritation.

Although skin protective products to prevent irritant skin reactions are in wide use, neither standardized test models to prove differences in efficacy exist, nor has the quality or the reproducibility of results been evaluated in a multicentre approach. This should be mandatory when developing or testing skin care products. Therefore, we have designed a multicentre study in an approach to find a standardized test procedure for the evaluation of skin protective products. In this irritation study, a repeated short-time occlusive irritation test (ROIT) with a standardized protocol has been evaluated in 2 phases (12 days and 5 days protocol) in 4 (n=20) respectively 6 (n=33) skilled centres. The skin reaction was induced by 2 irritants (0.5% aq. SLS and toluene, 2x a day for 30 min). Its modification by 3 different cream bases with different hydrophilicity was analyzed. The irritation was monitored by bioengineering methods (TEWL measurement, colorimetry) and by clinical scoring. The evaluation showed that significant results could already be achieved with the 5-day protocol. Furthermore, in spite of the expected inter-centre variations due to heterogeneity of the individual threshold of irritation, interpretation of clinical score, and inter-instrumental variability, the ranking of the vehicles regarding reduction of the irritant reaction was consistent in all centres.

Administration, Topical↗
PubMed1999

[Medialization of the tibial tuberosity in habitual dislocation of the kneecap].

Referring to relevant literature, various concepts are discussed in the treatment of habitual dislocation of the kneecap. Between 1987 and 1997, 88 patients have been treated surgically in our clinic by uni- or bilateral medial transfer of the tibial tuberositas. In 21 of the cases lateral release was also performed. In the follow-up, after an average of 4.9 years, 79 patients were examined clinically, radiologically and isokinetically (Kintrex-Dynamometer). Isokinetic measurement of the extension showed an average deficit of 19 nm compared to the contralateral side. Using the Juliusson and Markhede scores, 51 cases had a good, 18 a fair and 10 a poor clinical outcome. In 79 % of the cases, the postoperative sports activity level was the same as preoperatively. Isokinetic measurement with the Kintrex is a useful method of evaluating the development of muscle strength.

Adolescent↗
PubMed1999

[Microsurgical lumbar intervertebral disk operation. Technique and complications].

Lumbar Microdiscetomy requires special instruments and provides a good view with a narrow approach. The microscope is the best surgical aid. Alternatives are a retractorintigrated light or headlamp. A specific complication of lumbar microdiscectomy--the wrong level--can be minimized by an exact preoperative planning. Other complications like dural lesions and exessive bleeding are less frequent with the microscope because of the better view. The most severe complications that can occur with any lumbar disc operation, major vessel or visceral injury, can be avoided by lusing the new rongeur with a depth guard.

Diskectomy↗
PubMed1999

The frequency of phospholipase A2 binding of basophilic granulocytes does not decrease during bee-venom-specific immunotherapy.

BACKGROUND: The major allergenic component of bee venom is phospholipase A2 (PLA2). METHODS: In this study, PLA2 was used to analyze and enrich PLA2-binding cells from peripheral blood by high gradient magnetic cell sorting. RESULTS: In normal donors, the frequency of allergen (PLA2)-binding cells among peripheral blood mononuclear cells (PBMC) as determined by flow cytometry is below 0.1%, whereas in bee-venom-allergic patients, PLA2-binding cells are readily detectable at frequencies of up to 2.3%. In severely bee-venom-allergic patients, many basophilic granulocytes are present, as defined by anti-CD9, CD25, and CD38 mAb, comprising up to 95% of the PLA2-binding cells. From blood of allergic and normal donors, about equal absolute numbers of allergen-binding CD19/21-positive B cells can be enriched. Severe anaphylactic reactions (Mueller grade IV) and failure of or adverse reactions during immunotherapy are associated with high numbers of circulating allergen-binding basophils. Interestingly, in the patients studied, the number of PLA2-binding basophilic granulocytes did not markedly change during rush immunotherapy and up to 6 months of maintenance immunotherapy. CONCLUSIONS: The specific and reproducible enrichment of PLA2-binding cells provides a new tool for the analysis and monitoring of effector cells in bee-venom-allergic patients with immediate-type hypersensitivity.

Adolescent↗