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Biomedical subjects

K Konrad

Publications and source records attributed to K Konrad.

At least 37 records · Page 2Linked to original sources

Therapy with pulsed electromagnetic fields in aseptic loosening of total hip protheses: a prospective study.

Aseptic loosening is the most common problem of hip arthroplasties, limiting its long term success. We report a study of pulsed electromagnetic field (PEMF) treatment in 24 patients with this complication. At the end of treatment, six months and one year later, pain and hip movements improved significantly with the exception of flexion and extension. There was significant improvement in both isotope scans and ultrasonography, but not in plain X-ray. The decreased pain and improved function suggest that PEMF is effective in improving symptoms of patients with loose hip replacement. No improvement, however, can be expected in patients with severe pain due to gross loosening.

Adult↗

A dose related response of 6-OHDA on chicken spectral sensitivity and oscillatory potentials of recording electroretinograms.

OBJECTIVE: To further study the contribution of dopamine system to the local growth controlling mechanisms, a dose related response of 6-hydroxydopamine (6-OHDA) was studied by recording electroretinograms (ERGs). METHODS: The spectral sensitivity of the b-waves and spectral efficiency function of oscillatory potentials (OPs) including OP1, OP2 and OP3 in 4 different doses group were measured. The effect of ascorbate that must be contained in solution of 6-OHDA was first tested with the spectral sensitivity of the b-waves and a correlation between response of the OPs and age, as well as a difference in both own eyes was analyzed for determining an intra-subject and inter-subject variance. RESULTS: An enhanced response was found in OP1, OP2 with doses of 175 micrograms and OP3 with dose of 150 micrograms, and the effect of OPs was mainly in wavelength from 620 nm to 480 nm. No significant increase was found in the spectral sensitivity of the b-waves. The dose 200 micrograms seemed to be toxic to the retina estimated by both spectral sensitivity of the b-waves and spectral efficiency function of the OPs. CONCLUSIONS: The dose 175 micrograms and 150 micrograms of 6-OHDA yielded an effect on the chicken retina.

Adrenergic Agents↗

Elevated serum c-erbB-2 antigen levels and decreased response to hormone therapy of breast cancer.

PURPOSE: Decisions concerning the use of hormone therapy to treat metastatic breast cancer are made on the basis of the presence of estrogen receptor (ER). Despite the presence of ER, half of patients will not respond to hormone treatment. The purpose of this study was to determine the effect of overexpression of HER-2/neu on the response to hormone therapy. PATIENTS AND METHODS: Sera from 300 metastatic breast cancer patients with ER-positive (ER+), ER status unknown, or ER-/progesterone receptor-positive (PR+) randomized to receive second-line hormone therapy with either megestrol acetate or fadrozole were evaluated. An enzyme immunoassay (EIA) specific for the extracellular domain of the c-erbB-2 (HER-2/neu) oncogene product was used to detect serum levels. RESULTS: Fifty-eight patients (19.3%) had elevated serum c-erbB-2 protein levels, using a selected cut-point of 30 U/mL. The response rate (complete responses [CRs] plus partial responses [PRs] plus stable disease [S]) to endocrine therapy was 40.9% in 242 patients with low serum c-erbB-2 levels and only 20.7% in 58 patients with elevated serum c-erbB-2 levels (P = .004). The median duration of treatment response was longer in the group with low serum c-erbB-2 levels (15.5 months) compared with the group with elevated serum c-erbB-2 levels (11.6 months). Survival was also significantly shorter in patients with elevated serum c-erbB-2 levels (P < .0001). CONCLUSION: Patients with ER+/c-erbB-2+ metastatic breast cancer are less likely to respond to hormone treatment than ER+/c-erbB-2- patients. Their survival duration is also shorter.

Adult↗

Pigmented clear cell acanthoma.

We present five cases of macroscopically pigmented clear cell acanthomas. Masson-Fontana silver stain revealed dendritic melanocytes containing melanin granules in large numbers interspersed among the tumoral keratinocytes. The dendritic cells expressed S-100 protein. Electromicroscopy, performed on one pigmented clear cell acanthoma, showed melanosomes in large numbers in the dendrites of melanocytes; whereas only a few melanosomes were found in the adjacent keratinocytes, indicating a disturbed melanin transfer. We propose the name "pigmented clear cell acanthoma" for this variant of Degos' acanthoma.

Adult↗

Semiconductor laser-induced fluorescence detection in capillary electrophoresis using a cyanine dye.

Cy5, an activated carboxyl cyanine fluorophore, was characterized by capillary electrophoresis (CE) using a semiconductor laser at 652 nm to induce fluorescence. Hydrolysis of the activated Cy5 in the presence of ammonia results in the formation of a mono- and diamide and a dicarboxylic acid. A Cy5-labeled oligonucleotide M13 primer for DNA sequencing (M13mp18 template) was synthesized with a purity of better than 95%. The labeled primer was analyzed by liquid chromatography, using UV-visible detection, and by CE, monitored by laser-induced fluorescence (LIF) detection. Analysis of the Cy5-labeled oligonucleotide primer by CE-LIF in a 9% polyacrylamide gel-filled capillary indicated the purity of the major Cy5-oligonucleotide primer was greater than 90%. The detection sensitivity for Cy5-based CE-LIF detection system with a 2.5-mW red semiconductor laser is about 10(-10) M.

Base Sequence↗

Controlled trial of balneotherapy in treatment of low back pain.

Three treatments for non-specific lumbar pain--balneotherapy, underwater traction bath, and underwater massage--were assessed in a randomised prospective controlled trial in 158 outpatients. Each group was treated for four weeks and patients were reviewed at the end of this period and at 12 months after entry to the trial. The prescription of analgesics and the pain score were significantly reduced in all three treated groups, but there was no difference between the three groups. No significant change occurred in spinal motion and the straight leg raising test. After one year only the analgesic consumption was significantly lower than in the control group.

Adult↗

Hyperkeratosis lenticularis perstans (Flegel's disease). Ultrastructural study of lesional and perilesional skin and therapeutic trial of topical tretinoin versus 5-fluorouracil.

Lesional and perilesional skin samples from a 57-year-old man who had hyperkeratosis lenticularis perstans (HLP) (Flegel's disease) were studied by light and electron microscopic examination. Keratohyalin granules were diminished at the center of a fully-developed lesion. In contrast, keratohyalin appeared normal and membrane-coating granules were found in reduced numbers at the edges of the HLP lesion and were easily detected in normal numbers in clinically normal, perilesional skin. The inflammatory infiltrate in the HLP lesion was composed of small lymphocytes, which often displayed nuclei with deep infoldings resembling Sézary cells, and larger histiocytic cells, many of which were in close contact with the lymphocytes. Peripheral blood mononuclear cells did not show an abnormal ultrastructural appearance. Treatment with topical 5-fluorouracil cream led to the disappearance of the HLP lesions, whereas topical tretinoin was ineffective.

Administration, Cutaneous↗

Middermal elastolysis in an elderly man with evidence of elastic fiber phagocytosis.

BACKGROUND: Middermal elastolysis is a clinically and histologically distinct entity. This idiopathic loss of dermal elastic fibers has mostly been reported in younger adults. To our knowledge, the present case, which has been followed up for 4 years, is the first to occur in an elderly man. OBSERVATIONS: Two years after the onset of progressive wrinkling of the upper aspect of the thorax, the patient underwent a biopsy. Histologic examination of the specimens confirmed previous findings of middermal elastolysis. Examination of extracutaneous elastic tissue showed normal findings. Electron microscopy demonstrated elastic fibers embraced by macrophages, which is suggestive of elastic fiber phagocytosis. For the following 4 years, the patient has remained in stable clinical condition. CONCLUSIONS: Middermal elastolysis is probably more common than has been assumed so far. It does not affect nondermal elastic tissue. After progressive loss of dermal elasticity in a circumscribed area, a benign course follows, with a stable condition over several years. Electron microscopic findings indicate that elastic fiber phagocytosis is operative in the disappearance of the middermal elastic tissue.

Aged↗

Merkel cell carcinoma of the head and neck associated with Bowen's disease.

The Merkel cell carcinoma occurs primarily in the skin of the head and neck, and develops in the dermis with a trabecular growth pattern. Immunohistochemistry reveals positive staining for neuron-specific enolase, neurofilaments, cytokeratin and chromogranin A. Electron microscopically, the tumor cells contain dense-core granules, spinous cytoplasmic processes, desmosomes, zonulae adherentes and paranuclear filament aggregates besides frequent mitoses, focal necroses and lymphocyte and plasma cell infiltrates. The Merkel cell carcinoma is often co-existent with other malignancies such as squamous cell carcinoma or, as in the present study, with Bowen's disease. The definite diagnosis of the Merkel cell carcinoma can be effected only by electron microscopic examination of the tumor.

Aged↗

[Collodion baby with transition to mild lamellar ichthyosis.Clinical course, histopathology and ultrastructural findings].

The case of a collodion baby in whom the condition evolved into a mild form of lamellar ichthyosis is presented. The clinical course was impressive: the hard, collodion-like horny membrane started to crack soon after the birth and had detached completely at the 9th day of life; after a few more days, almost complete clearing of the skin had occurred. At the age of 10 months, the child had only a very mild lamellar ichthyosis. Whereas light microscopy revealed only compact hyperkeratosis on the 1st day of life, electron microscopy suggested a favourable prognosis even at this early stage, which has been corroborated by the ensuing clinical course.

Dermatologic Agents↗

Restenosis after transluminal coronary angioplasty: a risk factor analysis.

In order to determine the relationship of restenosis following percutaneous transluminal coronary angioplasty (PTCA) to risk factors such as hypercholesterolemia, hyperglycemia, smoking, and weight, we performed a univariate analysis to test the association of these variables with restenosis in 723 patients who had percutaneous transluminal coronary angioplasty and follow-up catheterization. Cholesterol levels were higher in younger and female subjects (less than 0.0001). Initial cholesterol did not predict restenosis, and follow-up cholesterol levels showed an inverse relationship with restenosis (P less than .02). There was a trend (P less than .09) toward decreased restenosis in those who were active smokers at the time of follow-up catheterization. No differences were seen in diabetics with hyperglycemia, in both treated and untreated groups (P = NS). A stepwise multiple logistic regression was used to simultaneously test the association of the above risk factor variables to restenosis. None of the interactions were found to be significant, except cholesterol at follow-up (P = .001). Therefore, the status of serum cholesterol, blood sugar, smoking, and weight during the time of PTCA and at follow-up catheterization may be unimportant in predicting restenosis. Thus, we conclude 1) that to better determine the effect of these variables on restenosis, they should be estimated at times other than follow-up and 2) that the pathophysiological mechanism of restenosis may have different risk factors than progression of atherosclerotic coronary artery disease.

Angioplasty, Balloon, Coronary↗

The ultrastructure of dysplastic naevi: comparison with superficial spreading melanoma and common naevocellular naevi.

Eleven dysplastic melanocytic naevi with various degrees of dysplasia, as judged by light microscopy, were studied by transmission electron microscopy, and their intra-epidermal melanocytes compared with those of five superficial spreading melanomas and seven common benign naevocellular naevi. Intra-epidermal melanocytes in dysplastic naevi exhibited signs of cellular atypia, which were most pronounced in the dysplastic naevi with histological high-grade dysplasia. A correlation between the degree of dysplasia at the light microscopic level and the degree of cytological atypia at the ultrastructural level was noted, and melanocytes in dysplastic naevi with a high degree of dysplasia had ultrastructural features similar to the melanocytes in superficial spreading melanomas. Our observations support the concept that dysplastic naevi fill the biological gap between benign naevocellular naevi and malignant melanomas and suggest that at least some of the dysplastic naevi must be regarded as potential precursor lesions of malignant melanoma, particularly those exhibiting a high degree of histological dysplasia.

Adult↗

Polypous clear cell acanthoma.

We report on two cases of polypous clear cell acanthoma. This growth pattern is unusual for the tumor and has not been reported in the literature. Histologically, these two tumors fulfill the criteria of clear cell acanthoma.

Female↗

Keratitis, ichthyosis and deafness (KID)-syndrome: report of three cases and a review of the literature.

We report three patients with keratitis, ichthyosis and deafness (KID)-syndrome. All had characteristic hyperkeratotic skin lesions and neurosensory hearing defects. Two had ophthalmologic symptoms. The third patient did not have eye involvement at the age of 3 years, but exhibited the other typical signs of the syndrome. In none of the three cases were any of the patients' relatives affected, and a spontaneous new mutation is the most likely explanation for the occurrence of this rare syndrome. Histopathological and electron microscopic studies revealed orthohyperkeratosis but no other pathology and no abnormal deposits of glycogen were found. Treatment with the aromatic retinoid etretinate proved to be of little value in any of the patients. The necessity for early audiologic and ophthalmologic evaluation and the need for life-long medical care for patients with KID-syndrome is emphasized.

Adult↗

Congenital melanocytic nevi with halo phenomenon: report of two cases and a review of the literature.

Verrucous congenital nevocellular nevi surrounded by a depigmented halo occurring in a 7-year-old boy and a 13-year-old girl were excised and the wounds closed primarily. Histopathologic studies revealed a striking arrangement of the inflammatory infiltrate in these halo nevi. A dense, band-like, lymphohistiocytic infiltrate was found only around and intermingled with A- and B-type nevomelanocytes in the upper dermis, whereas inflammatory infiltrates were completely absent from type C-nevomelanocytes in the lower parts of the reticular dermis. The literature is reviewed with particular consideration of congenital halo nevi.

Adolescent↗

[Histology of the skin and mucous membrane manifestations of AIDS].

The dermatopathologist must be aware of the wide spectrum of non-specific cutaneous manifestations, cutaneous infections and skin tumors associated with AIDS. We present the histological criteria essential for the diagnosis of early Kaposi's sarcoma, its differential diagnosis including epithelioid angiomatosis, as well as the diagnosis of oral hairy leucoplakia.

Acquired Immunodeficiency Syndrome↗