Biomedical subjects
Publications and source records attributed to W Stolz.
Pump-probe measurements were performed with a subwavelength spatial resolution of 355 nm and a temporal resolution of 130 fs in a multiple quantum well sample at T= 8 K. A solid immersion lens was used to increase the spatial resolution to 0.41 lambda, demonstrating that the limit of conventional microscopy was surpassed.
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We present a 2-year-old boy with a red, cutaneous-subcutaneous, nodule on the right elbow and a 2.5 year-old girl with an red-brown, indurated plaque on the left knee. Colour-coded doppler sonography of the boy's lesion showed vascular structures. A biopsy established the diagnosis of tufted angioma in both patients. Tufted angioma is clinically characterized by slowly spreading erythematous macules and plaques preferentially located on the upper trunk and neck in children. It is a benign tumor, malignant transformation has not been reported. The case history, clinical and histological findings contribute to the diagnosis. Tufted angioma has to be distinguished from Kaposi's sarcoma, angiosarcoma, hemangioma of infancy, sometimes bacillary angiomatosis and other cutaneous capillary malformations. Treatment of tufted angioma is difficult, various modalities like glucocorticosteroids, Interferon-alpha, flashlamp-pumped pulsed dye laser, excision and spontaneous regression have been described with varying results.
BACKGROUND: Pachyonychia congenita is considered to be a genodermatosis of autosomal inheritance. It is characterized by nail hypertrophy, shortly present after birth. Later on follicular keratosis of the extremities and hyperkeratosis of palms and soles can be found. HISTORY AND CLINICAL FINDINGS: We report a child with pachyonychia congenita type-I (Jadassohn-Lewandowsky). Shortly after birth nail hypertrophy of all finger- and toenails and leukoplakia of the palate and tongue were found. At the age of 3 years follicular keratosis of the extremities and plantar bullae could be found additionally. CONCLUSION: The underlying disturbance is a mutation within genes for keratin 6, 16 and 17 which leads to formation of abnormal tonofilaments. In adult patients retinoids can be used for symptomatic treatment especially of the palmoplantar keratosis.
BACKGROUND: Induction of melanocytic naevi by chemotherapy in children is reported in the literature. The reason for this phenomenon is not known yet. HISTORY AND CLINICAL FINDINGS: We present a 6-year-old girl who fell ill with acute lymphoblastic leukemia at the age of 2 years. After a combined chemotherapeutic treatment for 2 years followed by complete remission of leukemia, many (> 100) small pigmented naevi appeared over the whole body. The naevi did not show features suggestive of dysplasia. CONCLUSIONS: Patients with excess numbers of melanocytic naevi constitute a risk group for malignant melanoma, therefore periodic skin examination is recommended.
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Microsatellite instability (MSI) is caused by deficient DNA mismatch repair, and results in a "mutator" phenotype. Recent studies have produced contradictory results about the frequency and significance of MSI in malignant melanomas. In this study, we therefore determined the time of onset and relative frequency of MSI during the progression of melanocytic tumours, including benign melanocytic naevi. We examined 7 different microsatellite loci in 9 melanocytic naevi, 25 primary malignant melanomas and 8 melanoma metastases. None of the melanocytic naevi showed MSI. In contrast, moderate frequency of MSI in 1/12 (8%) was detected in thin melanomas of <0.75 mm vertical thickness and in 1/8 (12%) of those with a thickness >0.75 mm and < 1.5 mm. The rate of MSI was increased in tumours thicker than 1.5 mm (2/5) and in melanoma metastases, with over 25% (2/8) of the lesions investigated. We conclude that MSI occurs in a considerable subset of malignant melanomas and that there is a pattern consistent with increasing frequency of MSI with progression of melanocytic tumours.
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Two boys, age 7 and 9 years, with the diagnosis of primary anetoderma are presented. In one patient a growing number of indolent lesions developed for one year on the neck. The other boy complained of single lesions appearing over four months on the arms, feet, and chest wall. Individual lesions measured up to 1 cm in diameter and showed a palpable herniation phenomenon and wrinkled surface. The lesions did not have an inflammatory onset. Histologically, in both patients the diagnosis of anetoderma was verified by loss of elastic fibers and a lympho-histiocytic infiltration in the middermis. Administration of oral penicillin for three weeks did not result in marked improvement, and atrophic macules continued to appear in the younger boy. Although no autoimmunologic abnormalities or other associated diseases have arisen in our patients, long-term follow-up is mandatory to detect autoimmune disorders that are reported to occur in the course of the disease.
It has recently been shown that the serum level of melanoma-inhibitory protein (MIA) provides useful information for the therapy and follow-up of patients with malignant melanoma. Previously, S100 beta has been described as a useful tumor marker for malignant melanoma. In this study, we compare the significance of the two markers in follow-up, therapy outcome and prognosis by measuring MIA and S100 beta serum levels in 50 melanoma patients. Serum levels were measured in patients with malignant melanomas of stages I-IV with at least 3 time points of measurement. Serial MIA and S100 beta measurements were obtained from 32 patients with stage IV disease in parallel to chemotherapy and from 18 patients with a history of stage I and stage II disease during follow-up. The response to chemotherapy in stage IV disease and relapse of melanoma during follow-up correlated with changes in MIA and S100 beta serum levels. In comparison, MIA revealed slightly higher specificity and sensitivity. In conclusion, both markers are useful for detection of progression from localized to metastatic disease during follow-up and for monitoring therapy of advanced melanomas.
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While there is evidence for the use of liposomes as drug carriers upon topical application to the skin, the underlying mechanisms are far from being clear. Therefore human keratinocytes grown in vitro were exposed to large oligolamellar liposomes. After attachment and invagination these particles can be found unchanged within the cytoplasm both inside and outside of lysosomes. If incorporated into lysosomes the structural lipids can be disintegrated and spread within the entire phagolysosome. Gold labeling adds further to the hypothesis of intact uptake of liposomes by the living cells of the human epidermis.
MIA was isolated previously as a small soluble protein secreted from malignant melanoma cell lines in vitro. Highly restricted expression patterns in melanocytic tumors were identified in vivo. We therefore quantitated serum levels of MIA protein by means of a non-radioactive ELISA and investigated whether MIA provides clinically relevant parameters in patients with malignant melanomas. Here we report enhanced MIA serum levels in 13% and 23% of patients with stage I and II disease, respectively, and in 100% with stage III or IV disease. Response to therapy in stage IV disease correlated with changes in MIA serum levels and surgical removal of metastases led to normalization of serum values. Repeated measuring of sera from 350 patients with a history of stage I or II melanoma during follow-up, we detected 32 patients developing positive MIA values. At the time of serum analysis 15 of them had developed metastases and one presented with metastatic disease 6 months later. In conclusion, MIA represents a novel serum marker for systemic malignant melanoma revealing the highest sensitivity and specificity among currently available markers.
Until now, it has been possible to determine fetal pulmonary maturity only by amniocentesis. Since the functional changes of the fetal lung leading to maturity are also morphologically apparent, pulmonary maturity can be demonstrated sonographically. Obtaining a uniform value for maturity is a problem, since the position of the fetus, the mother's constitution and the instrument setting all influence assessment. The fetal liver was therefore used as a reference organ, since it is subject to the same influences. By frequency analysis of both organs and calculation of the ratio between the frequencies obtained, a mathematical value can be calculated by which pregnancies can be compared and which, as our studies showed, represents a measure of pulmonary maturity. This was documented in 348 patients. It was shown by amniocentesis in 32 patients and the postpartal condition of 25 premature births that a value of 1.11 for this ratio between lung and liver represents the borderline between pulmonary immaturity and maturity. Lower values indicate maturity. If these results are confirmed by further studies on larger groups of patients, it will in future be possible to determine fetal pulmonary maturity very easily and non-invasively.
Doppler sonographic measurements of the fetal aorta and the carotid artery were performed on 198 pregnant patients having been diagnosed with a placental insufficiency. A relationship between them and fetal as well as non-fetal factors was examined. For the fetal factors minus difference in weight of birth and perinatal morbidity there could be established a definite correlation with corresponding resistance-index (RI) of the examined vessels. The criteria for the fetal outcome Apgar-note and pH-value of the cord blood didn't show absolutely equal changes with a deteriorated blood perfusion, what might be due to the management of birth as well as it indicates the close correlation of these values with the course of birth. Among the non-fetal factors there could be shown close relationships between the duration of pregnancy as well as age and the values of resistance-indices. While the ones, mentioned first, decreased in an almost linear relationship with RI-deterioration, did the fetal circulatory situation ameliorate with an increasing maternal age. Possible factors of influence, especially on the duration of pregnancy as well as the relationship between the maternal age and the fetal condition of perfusion were discussed. Pulsed doppler sonographic measurement is an efficient step in diagnosing a suspected placental insufficiency and has an outstanding value in an early recognition of possible dangers for the fetus.