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H Merk

Publications and source records attributed to H Merk.

At least 19 recordsLinked to original sources
PubMed2006

[Correlation between sex, intrauterine position and familial predisposition and neonatal hip ultrasound results].

AIM: To correlate findings of hip ultrasound on day 4-10 of life with sex, intrauterine position and a positive family history for congenital hip anomalies. METHODS: The SNiP-study ( Survey of Neonates In Pommerania) registered 2256 neonates (2030 term, 226 preterm) between May 2002 and March 2004. Hip ultrasound results of 1043 term and since October 2003 33 preterm neonates were analysed. Time of ultrasound was day 4-10 after birth. Preterm neonates were examined when reaching their corrected term gestational age. Ultrasound was applied with a 7.5 MHz linear scanner and results were classified according to Graf. Chi-square and Fishers exact test were used for statistical analysis. RESULTS: 4.9 % of the screened hips were classified as IIc or higher, 3.1 % were unilateral and 1.7 % bilateral. Incidence was significantly higher (p < 0.023) in females (6.6 %) than in males (3.2 %). There was no significant difference in intrauterine position or positive family history for hip anomalies with 3.7 % for mothers, 1.2 % of fathers and 2.4 % of siblings positive. There was a higher incidence for congenital hip dysplasia in preterms with 6.1 %, which is not significant due to the limited number. DISCUSSION: Current screening methods miss up to 18 % of newborns with severe hip dysplasia. We were able to demonstrate that screening for congenital hip dysplasia with ultrasound is a diagnostic tool even during the first days of life. There is a significantly higher incidence of congenital hip dysplasia in females, but in contrast to other studies we found no significant difference in intrauterine position or familial history. Earlier diagnosis and therapy on the base of relevant risk factors might correspond with an improved prognosis and outcome. Further studies are warranted to evaluate the significance in preterm neonates.

Female↗
PubMed2006

[Results of SaluCartilage implantation for stage IV chondral defects in the knee joint area].

AIM OF STUDY: This prospective report presents SaluCartilage hydrogel implants, an alternative therapy option in the treatment of chondral defects. METHODS: For the prospective study between October 2002 and July 2003, 18 patients suffering from stage IV chondral defects received 49 hydrogel implants and were subsequently examined by means of clinical, radiological, and magnetic resonance imaging assessment. The knee function was classified using the McDermott score. RESULTS: The average McDermott score was improved to 75 points (p<0.05) after 3 months postoperatively and to 80 points (p<0.05) 6 months postoperatively, but after 12 months it decreased to 69 points. After 3 and 6 months, the MRI showed in all patients that there was fluid around the hydrogel implants without dislocation. After 12 months postoperatively the hydrogel implants had been destroyed in two patients. CONCLUSION: The short-term results showed subjective and objective improvement of the medical conditions probably because of the placeholder function. This alternative should be critically discussed because of the inadequate connection to the bone with risk of dislocation.

Arthroplasty, Replacement, Knee↗
PubMed2006

High-resolution optical coherence tomography as a non-destructive monitoring tool for the engineering of skin equivalents.

BACKGROUND: Three dimensional skin equivalents are widely used in dermatopharmacological and toxicological studies and as autologous transplants in wound healing. In pharmacology, there is tremendous need for monitoring the response of engineered skin equivalents to external treatment. Transplantation of skin equivalents for wound healing requires careful verification of their quality prior to transplantation. Optical coherence tomography (OCT) is a non-contact, non-destructive imaging technique for living tissues offering the potential to fulfill these needs. This work presents an analysis of OCT for high-resolution monitoring of skin equivalents at different stages during the culture process. METHODS: We developed a high-resolution OCT imaging setup based on a commercially available OCT system. A broadband femtosecond laser light source replaces the original superluminescence diode. Tomograms of living skin equivalents were recorded with an axial resolution of 3 mum and correlated with histology and immunofluorescence images. Comparison with standard low-resolution OCT is presented to emphasize the advantages of high-resolution OCT for this application. RESULTS: OCT is particularly able to distinguish between different layers of skin equivalents including stratum corneum, epidermal and dermal layer as well as the basement membrane zone. The high-resolution OCT scans correlate closely with two key benchmarks, histology and immunofluorescence imaging. CONCLUSIONS: This study clearly demonstrates the benefits of high-resolution OCT for identifying living tissue structure and morphology. Compared with the current gold standard histology, OCT offers non-destructive tissue imaging, enabling high-resolution evaluation of living tissue morphology and structure as it evolves.

Basement Membrane↗
PubMed2005

[In vitro testing for allergic contact dermatitis].

Patch testing is the standard method to identify allergic contact dermatitis. Simple, safe and accurate in vitro methods identifying contact allergies would offer both theoretical and practical advantages. Using the lymphocyte transformation test (LTT), allergen-specific lymphocytes central to the pathogenesis of Type IV allergies can be identified. Various studies have assessed the value of LTT in the diagnosis of contact allergies. The current assessment is that the test can be helpful in distinguishing between irritant and allergic reactions. LTT is especially useful in demonstrating drug allergies and can also be employed to prove sensitization to gases or toxic substances. At the present time, it is not an alternative for patch testing in daily practice.

Allergens↗
PubMed2004

[Bone healing in drill hole defects in spontaneously diabetic BB/OK rats. A histomorphometric and biomechanical study].

The objective of this study was to examine changes in the histomorphometric and mechanical evaluation of the influence of the diabetic metabolic state on defect healing depending on the defect size in spontaneously diabetic BB/O(ttawa)K(arlsburg) rats. Based on blood glucose levels and postoperative insulin requirements, 120 spontaneously diabetic BB/OK rats were divided into groups with well-compensated or poorly compensated metabolic state. Sixty LEW.1A rats served as the normoglycemic controls. Bone defects of different sizes were created proximal to the knee joint space and then allowed to heal for 2, 4, and 6 weeks. Bone defect sizes > or =0.8 mm showed significant differences in the structural calculations and bone defect sizes > or =1.2 mm showed a significant decrease of all fluorochrome-based parameters of mineralization exclusively in the rats with poorly compensated diabetic metabolic state as well as significantly decreased values of biomechanical properties in comparison to the spontaneously diabetic rats with well-compensated metabolic states and to the control rats. Bone repair of minor bone defects is independent of the diabetic metabolic state in the spontaneously diabetic BB/OK rats. With controlled insulin therapy and resultant well-compensated diabetic metabolic state, severe mineralization and biomechanical disorders in healing of larger bone defects in the poorly compensated diabetic metabolic state of the experimental animal can be avoided.

Animals↗
PubMed2004

Improving metabolic control reverses the histomorphometric and biomechanical abnormalities of an experimentally induced bone defect in spontaneously diabetic rats.

Insulin-dependent type 1 diabetes mellitus (IDDM) has been shown to alter the properties of bone and to impair fracture-healing in both humans and animals. The objective of this study was to examine changes in the histomorphometric and mechanical parameters of bone and remodeling during bone-defect 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 humans. A standardized bone-defect 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). A total of 120 spontaneously diabetic BB/OK rats were divided into groups with a well-compensated (n = 60; 169 +/- 102 mg%; 230 +/- 126 mg%; and 2.2 +/- 1.1 IU/ kg) or poorly compensated (n = 60; 380 +/- 159 mg%; 359 +/- 89 mg%; and 5.4 +/- 1.1 IU/kg) metabolic state. Sixty LEW.1A rats served as the normoglycemic controls (93 +/- 19 mg%). Fifteen animals from each group were killed on postoperative days 7, 14, 24, and 42, and specimens were processed undecalcified for quantitative bone histomorphometry and for biomechanical testing. Our study showed in terms of bone histomorphometry, within the first 14 days, that severe mineralization disorders occurred exclusively in the rats with a poorly compensated diabetic metabolic state with a highly significant (P < 0.001) or significant (P < 0.01) decrease of all fluorochrome-based parameters of mineralization, apposition, formation and timing of mineralization, as well as significantly decreased values of biomechanical properties (P < 0.05) in comparison to the spontaneously diabetic rats with a well-compensated metabolic state and to the control rats. Bone-defect healing in spontaneously diabetic BB/ OK rats is retarded exclusively in a poorly compensated diabetic metabolic state. This study suggests that strictly controlled insulin treatment resulting in a well-compensated diabetic metabolic state will ameliorate the impaired early and late parameters of IDDM bone-defect healing.

Animals↗
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↗