Search PubMed⌕ Search

Biomedical subjects

C Schmidt

Publications and source records attributed to C Schmidt.

At least 523 records · Page 29Linked to original sources
PubMedDate not supplied

[Portable NMR-MOUSE: a new method and its evaluation of the Achilles tendon].

AIM: The increased demands placed on the Achilles tendon in recreational and professional sports have led to a rise in pathological changes in this anatomic region. Magnetic resonance evaluations of the tendon have proven to be a valid but expensive and stationary diagnostic tool. In this study, a new mobile NMR sensor was to be tested in the evaluation of the Achilles tendon. METHOD: The technical development of the so-called NMR-MOUSE ( Mobile Universal Surface Explorer) represents a novelty with an open and portable sensor. To appraise its diagnostic efficacy, healthy athletes (professional soccer players, track and field, as well as aquatic athletes), healthy controls and patients with Achilles tendon lesions were evaluated. As an accessible, sensitive and reproducible parameter for the study the transverse relaxation time T2 with its angular dependency was chosen. As part of the examination, the relaxation times of the skin, the tendon and the surrounding soft tissue were determined. RESULTS: During the evaluation with the NMR-MOUSE, the skin and peritendineous tissue exhibited relatively long T2 relaxation times, while the tendon itself had significantly shorter T2 times, allowing for a clear differentiation of the structures. The T2 relaxation time of the Achilles tendon in the control group averaged 5.8 ms. The MRI-MOUSE was able to demonstrate an increase in the T2 relaxation times in patients with pathological lesions of the tendon due to the increased water retention of the tissue. CONCLUSION: The novel NMR-MOUSE represents a cost efficient and portable sensor, which allows for a reliable evaluation of surface structures, such as the Achilles tendon. The anisotropic structure of the tendon and the surrounding soft tissue can be reliably differentiated with the help of the NMR-MOUSE.

Achilles Tendon↗
PubMedDate not supplied

[Delayed-type skin reaction in children with malignant diseases].

The delayed type hypersensitivity reaction has been employed in order to study the cell-mediated immunity in 103 children and adolescents with malignant tumors, using the Multitest system (Mérieux). This skin test allows the simultaneous application of seven various recall-antigens in a standardized fashion and proved to be very predicative in normal children and adolescents at the age of 1-30 years, since beyond infancy no major variations of the test results has been observed in older age groups and a complete anergy has only been seen in 1.8%. The tumor patients were divided in three groups (50 patients with leukemia and malignant lymphoma, 23 patients with malignant bone tumors and 30 patients with other malignant diseases) and studied at the beginning or under chemotherapy. A significant decrease of skin reactions or a total anergy were found in all tumor groups compared to the normal control group and regardless the duration of chemotherapy. This was more pronounced in patients with systemic malignancies than in solid tumors. The largest group of the ALL- and NHL-patients showed a severely depressed cell-mediated immunity or complete anergy at the beginning of chemotherapy and subsequently improved already during the induction phase of chemotherapy. If improvement was missing, it was highly suspicious for relapse. In addition, such an increase of skin reactivity could not be demonstrated in few relapse patients during reinduction therapy. Patients with malignant bone tumors did not show such a dramatic depression of cell-mediated immunity at the beginning of chemotherapy and the results correlated with the course of the intervall chemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

[The behavior of 3-phase scintigraphy of hip joint prostheses].

With the results of about 600 hip joint prostheses examined by scintigraphy, it is evident that nuclear medicine is more than a supplementary examination, especially in the case of a non-cemented isoelastic prosthesis. The combination of 3-phase scintigraphy with leukocyte scintigraphy could solve the problems of infected and aseptic displaced prostheses in 90% of the cases. The conventional X-ray diagnostic being the only method to demonstrate bone morphology is still the primary examination.

Femur↗
PubMedDate not supplied

Peptidyl substrates containing unnatural amino acid at the P'1 position are potent inhibitors of prohormone convertases.

In order to study further the importance of the P'1 residue upon the activity of human PC1 and human furin, two important members of subtilisin/kexin family of enzymes, we have prepared by solid-phase Fmoc or recently introduced FastMoc chemistry a series of 10 peptidyl substrate analogs. The structures of these analogs are based upon the core sequence of pro-mPC1(83-93) namely, D-Tyr-Lys-Glu-Arg-Ser-Lys-Arg-Xaa-Val-Gln-Lys-Asp, where D-Tyr replaces the native L-Tyr residue and Xaa, representing the P'1 position, corresponds to L-Ser or to nonproteinacous amino acids such as Tle, Sarc, MLeu, Aib, D-Tic or L-Tic. Two more analogs with L-Tic at P'1 position but with one amino acid less, namely P5 Glu or P'3 Gln, and one with a Cit residue in place of Arg at P1 site of the dodecapeptide were also obtained. These peptides were all fully characterized by a combination of MS, 1H-NMR and amino acid analysis. In contrast to the Ser analog, which is an excellent substrate for both hPC1 and hfurin, these analogs displayed moderate to strong inhibition of both hPC1 and hfurin activity in a reversible competitive manner. They all exhibited higher potency for hfurin than for hPC1, with an inhibition constant (Ki) ranging from 0.8 to 10 microM and from 1.0 to 170 microM, respectively. Incorporation of L-Tic yielded an analog with a two to four-fold increased inhibition of either enzymes when compared to its D-Tic counterpart, the effect being more pronounced for hPC1 than for hfurin. Comparison of these data with those for the corresponding N-terminal Fmoc protected peptides revealed that the highly hydrophobic N-terminal Fmoc function occupying the P8 position can contribute positively or negatively towards proteinase inhibition depending on the nature of the unnatural amino acid at P'1 and the enzyme used. Finally, none of the analogs was significantly cleaved by either enzyme. FTIR data on these analogs revealed some important structural differences between the substrate and inhibitor analogs, as there appears to be a conformational shift from a more beta-sheet-like structure for the substrates to a more alpha-helical-like structure for the inhibitors.

Amino Acid Sequence↗
PubMedDate not supplied

Stress on the job.

Explore the source record for details and available documents.

Allied Health Personnel↗
PubMedDate not supplied

Immunoglobulins and IgG subclasses in patients with inflammatory bowel disease.

BACKGROUND/AIMS: Serum immunoglobulin levels and distribution are altered in patients with inflammatory bowel disease (IBD). The purpose of this study is to examine the value of serum concentration of IgG subclasses for the diagnosis and evaluation of disease activity of IBD and to assess possible differences in the immunoglobulin changes between patients with Crohn's disease (CD) and ulcerative colitis (UC). METHODOLOGY: We measured serum IgG and IgG subclasses concentrations as well as IgA, IgM, ESR, CRP, elastase levels and granulocyte count of 96 patients with chronic IBD (69 with CD and 27 with UC) with various levels of disease activity. RESULTS: The total IgG levels in patients with UC were significantly increased, for both active and inactive disease, compared to those of patients with CD. The IgG1 concentration in patients with UC (7+/-0.77 mg/ml) was significantly higher than in patients with CD (5.6+/-0.61 mg/ml) (p<0.02). The IgG2 levels in CD were significantly higher than those of UC (4.6+/-0.64 vs. 3.8+/-0.57 mg/ml) (p<0.05). The IgG4 levels of UC patients were significantly higher than those of the CD patients (0.39+/-0.06 vs. 0.29+/-0.05 mg/ml) (p<0.05). No significant differences were found in the serum concentrations of IgG3, IgA and IgM between the two groups. There was a negative correlation between the various indices of disease activity and the concentration of IgG3 in patients with UC (p<0.01), and a positive correlation in patients with CD for IgG1 (p<0.001), IgG2 (p<0.001) and IgA (p<0.01). CONCLUSIONS: In IBD some of the IgG immunoglobulin subclass concentration changes correlate, positively or negatively, with disease activity and therefore could be used as additional markers of it. However, serum immunoglobulin levels cannot be used to differentiate between UC and CD.

Adult↗
PubMedDate not supplied

Neutrophil-elastase in chronic inflammatory bowel disease: a marker of disease activity?

BACKGROUND/AIMS: Neutrophil elastase is a proteinase which exists in granulocytes and plays an important role in the pathogenesis of inflammatory disorders. In inflammatory bowel disease there is a leukocyte infiltration of the bowel mucosa. The purpose of this study was to examine whether plasma elastase represents a reliable laboratory marker for establishing the activity of chronic inflammatory bowel disease. METHODOLOGY: We measured plasma elastase concentrations in 61 patients suffering from either Crohn's disease or ulcerative colitis and compared these data with other clinical and laboratory findings and with elastase concentrations in 40 healthy controls. The sensitivity and specificity of the elastase values in chronic IBD were calculated with the use of concomitant measurements of CRP and ESR. RESULTS: Plasma levels were found to be significantly higher in patients (49 micrograms/l) compared with healthy controls (23 micrograms/l). Patients with active disease had higher plasma levels than patients in remission. In general, the sensitivity of elastase to detect active inflammatory bowel disease was about 60%; the specificity was 65%. For patients in remission, the sensitivity was higher than 80%. However, there was a wide range of overlapping values between chronic inactive patients and those with moderately active disease. CONCLUSIONS: We conclude that plasma elastase is a useful independent marker of disease activity in inflammatory bowel disease. Especially for identifying patients in remission, the measurements of elastase seem to be more suitable than other parameters of inflammation, like CRP or ESR.

Adult↗
PubMedDate not supplied

Primary squamous cell carcinoma of the stomach. Report of a case and review of literature.

Primary squamous cell carcinomas of the stomach represent a rare entity. Since the first report in 1895 by Rörig et al. (1) only 80 cases have been published. These reports show a peak incidence in the sixth decade of life and preference of male gender (5:1). We report the case of a 61-year-old patient who presented with anemia and weight loss due to a large tumor of the gastric wall with adhesion to the pancreatic tail. After radical regional "en bloc" gastrectomy, splenectomy and pancreatic tail resection, the diagnosis of primary gastric squamous cell carcinoma could be confirmed, since the esophageal wall and the pancreatic tail were not infiltrated and extragastric squamous cell primaries could be excluded. After postoperative irradiation of the upper abdominal area, the patient developed a single liver metastasis in the left hepatic lobe that decreased with polychemotherapy. It was resected half a year later. Due mainly to advanced tumor stages, survival after surgical resection is poor. However, adjuvant radio and chemotherapy have resulted in survival rates of more than 3 years in reported cases, as in the present case. Five years after the diagnosis was established the patient is free of recurrence and without any complaint. Pathophysiological features, therapy and outcome are discussed by reviewing the cases reported in world literature.

Carcinoma, Squamous Cell↗