[Frustration = loss of motivation].
Explore the source record for details and available documents.
Humans↗
Biomedical subjects
K Wolff
Publications and source records attributed to K Wolff.
[Infestation of a cattle herd with the ear mite Raillieta auris (Acarina, Mesostigmata)].
An infestation with Raillietia auris in a 4 years old cow is reported. For a period of 3 weeks the animal showed an increasing unrest, extreme efforts while trying to feed, and continuous shaking of the head which slanted to the left. After slaughter numerous specimens of the ear-mite R. auris were found in the basic part of the left auditory canal, located in the vicinity of a purulent paste-like plug. Histological examinations of the brain revealed a severe non-purulent meningoencephalitis with necroses of the vascular walls, focal malacia and gliosis. An etiological correlation of these lesions with the mite-infestation, however, is considered to be most unlikely. To the best of our knowledge the occurrence of R. auris in Switzerland was up to now unknown.
Animals↗
Methadone concentrations in plasma and their relationship to drug dosage.
We have developed a sensitive HPLC method for measuring methadone in plasma and have used it to establish that there is a linear relationship between plasma concentration and methadone dose over the range of 3-100 mg of methadone per day in a group of 31 addicts. We found a good correlation between dose and plasma concentration (r = 0.89), with the plasma methadone concentration increasing by 0.263 mg/L for every milligram of methadone consumed per kilogram of body weight. Five patients had unexpected high or low concentrations; this finding is discussed.
Chromatography, High Pressure Liquid↗
[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↗
Human epidermal T cells predominantly belong to the lineage expressing alpha/beta T cell receptor.
The epidermis of clinically normal-appearing human skin harbors a phenotypically heterogeneous population of T lymphocytes (TCs), the majority of which are CD2+/CD3+/CD5+ "memory" cells, but in an unactivated state, and express the TCR-alpha/beta. In contrast to murine skin, only a very minor subpopulation of CD3+ cells in the human epidermis bears the TCR-gamma/delta. Epidermal TCs primarily are distributed along the rete ridges in the basal keratinocyte layer and are often in close apposition to Langerhans cells (LCs). These TCs were propagated from epidermal cell suspensions after stimulation with TC activating agents (Con A, rIL-1, rIL-2), then evaluated for phenotypic features and TCR diversity. Similar to the in situ situation, most were CD4-/CD8+/TCR-alpha/beta+. In addition, two cultures contained TCR-gamma/delta+ cells; one of these determined to be an adherent CD4-/CD8+ population. Epidermal TCs were significantly (p less than 0.0001) more abundant in the sole than in the other body regions examined (i.e., 40 vs. 7 CD3+ cells/linear centimeter of epidermis) and seemed to have a particular affinity for the acrosyringial epithelium of eccrine sweat ducts. Moreover, the sole usually contained a greater number of CD8+ relative to CD4+ TCs, whereas the epidermal CD4/CD8 ratio in the trunk and extremities was quite variable, although the trend also was towards a slightly larger percentage of CD8+ cells. Collectively, our data suggest that the volar epidermis has a unique microenvironment which is responsible for both the higher density of TCs, preferentially CD8+, and lower number of LCs. This study has not only provided evidence for significant regional variability in the human epidermal TC population of normal skin, but also strengthens the concept for skin-associated lymphoid tissues (SALT), whereby memory TCs recirculate back to the epidermis and interact with resident antigen-presenting cells (i.e., LC).
Antibodies, Monoclonal↗
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↗
Langerhans cells in HIV-1 infection.
The skin-specific immune surveillance system protects against invading microorganisms and transformed cells expressing tumor-specific neoantigens. This system includes antigen-presenting Langerhans cells, dermal and epidermal T lymphocytes, cytokine-producing keratinocytes, and draining peripheral lymph nodes. In patients infected with human immunodeficiency virus-1 (HIV-1), this surveillance system appears to be compromised, as evidenced by a reduction in the epidermal Langerhans cell population. Because human epidermal Langerhans cell express surface-bound CD4 antigens, HLA-DR antigens, and Fc-IgG receptors, all of which are involved in HIV-1 binding to, or entry into, the target cell, the reduction in Langerhans cells in patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC) may be a direct consequence of HIV-1 infection and subsequent injury to Langerhans cells. Detailed ultrastructural studies have confirmed moderate to severe morphologic damage in some Langerhans cells of such patients and the presence of HIV-1-like particles on Langerhans cell surface membranes and in the extracellular spaces. The biologic consequences of Langerhans cell infection by HIV-1 could be either impaired antigen presentation function of viable Langerhans cells or possible transmission of the retrovirus to the T-cell compartment in skin or lymph nodes, with subsequent depletion of CD4+ T cells via widespread syncytia formation between HIV-1-infected and noninfected cells. The facts that herpes simplex virus, specific cytokines, and ultraviolet B radiation can activate signals for HIV-1 expression and that epidermal cells can elaborate large amounts of cytokines, particularly with enhanced ultraviolet B exposure, may have important clinical implications for HIV-1-infected patients.
Acquired Immunodeficiency Syndrome↗
Photochemotherapy improves chronic cutaneous graft-versus-host disease.
We have used oral psoralen photochemotherapy (PUVA) to treat four patients with chronic graft-versus-host disease of the skin, oral mucosa, and liver, who had responded only partially to long-term immunosuppressive therapy (prednisolone, cyclosporine, azathioprine). PUVA therapy was delivered to the entire skin but not to the oral mucosa, and immunosuppressive therapy was continued in all patients. Two patients' skin lesions improved considerably; the oral lesions healed and did not recur in one. Immunosuppressive therapy could be reduced in these two patients. One patient with sicca signs did not improve. One patient had to interrupt PUVA therapy because of side effects attributed to 8-methoxypsoralen (nausea and vomiting). No flare of acute cutaneous graft-versus-host disease was noted during PUVA therapy. Chronic graft-versus-host disease of the liver did not improve in any patient.
Adolescent↗
Elective regional lymph node dissection in malignant melanoma.
In patients with malignant melanoma elective regional lymph node dissection (ELND) is controversial. This retrospective study evaluated differences in prognosis in patients who were treated with or without ELND. 168 patients were included who initially presented with stage I melanoma (without palpable regional lymph nodes), and who had a minimum observation period of at least 5 years, or had died of malignant melanoma within 5 years of diagnosis. In 66 patients a wide local excision (WLE) followed by ELND was done. In 102 cases only a WLE was done. Assignment of patients to the two groups was non-random but there was no significant difference in age, sex, type and location of primary tumour and depth of invasion. No significant difference was found in survival of the two groups. The 5 year survival of the WLE group was 85.7% and that of the WLE plus ELND group was 89.1%. The 10 year survival rate was 77.9% and 73.1%, respectively. Neither in the whole series nor after sub-division of the patients into three classes according to Breslow depth of invasion (up to 1.5, 1.51-2.5, and greater than 2.5 mm) was a significant influence of ELND on the survival of patients apparent. Cox's regression model did not show ELND as a prognostic factor. ELND cannot be recommended as a routine treatment in patients with stage I melanoma.
Adult↗
An aid to the selection of chemotherapy regimens for oral cavity carcinomas. Early results of a study of 5-year survival based on antioncogram selection of anti-cancer drugs.
The antioncogram is an aid to the selection of cytostatic drugs in the treatment of oral cavity carcinomas. In comparison with drug selection based on clinical experience, the antioncogram-oriented choice of the most promising drug in vitro results in improved survival rates.
Adult↗
Thymus-independent generation of Thy-1+ epidermal cells from a pool of Thy-1- bone marrow precursors.
Thy-1+ dendritic epidermal cells (Thy-1+ DEC) and immature thymocytes share several phenotypic features: CD45+, Thy-1+, asialo-GM1+, CD3+, CD4-, and CD8-. In view of this similarity, it has been suggested that the epidermis may be a site of either post-thymic or extra-thymic T-cell development. In order to address this issue, we used C3H/He/Han (Thy-1.2)----AKR/Ola (Thy-1.1) radiation bone marrow chimeras. Animals were first either thymectomized or sham-thymectomized, then lethally irradiated (750R) and, finally, reconstituted with allogeneic bone marrow cells previously depleted of Thy-1-bearing cells. Six weeks after bone marrow transplantation, spleens and lymph nodes of sham-treated animals, but not of thymectomized animals, contained large numbers of CD3+ donor-type Thy-1+ cells. The epidermis of both thymectomized and sham-treated animals contained not only many recipient-type CD3+, Thy-1+ DEC, but also small numbers of CD3-, donor-type Thy-1+ cells. After 4 months, the frequency of donor cells had greatly increased, but they still lacked CD3 antigens. Most of the donor cells had a rounded shape, but some exhibited a dendritic configuration. These results demonstrate that Thy-1- bone marrow-derived precursors of Thy-1+ DEC can migrate to the epidermis without thymic influence and yet acquire Thy-1 antigens during their journey. Although donor-type Thy-1+ epidermal cells failed to mature into CD3+ dendritic epidermal cells, the experimental model used in this study may be a versatile tool for studying the influence of thymic and extrathymic epithelia on T-cell maturation.
Animals↗
Immunogold staining of intermediate-sized filaments of the vimentin type in human skin: a postembedding immunoelectron microscopic study.
We have studied the localization of vimentin in normal human skin at the ultrastructural level using a monoclonal mouse anti-vimentin antibody and a postembedding immunogold-staining technique on thin sections of Lowicryl K4M embedded biopsies. Selective immunogold labeling of intermediate-sized filaments (IF) of epidermal Langerhans cells and melanocytes and of dermal fibroblasts was demonstrated. The IF of fibroblasts were more intensely stained than those of the epidermal dendritic cells; cell processes and dendrites of all three cell populations exhibited a greater number of IF and more pronounced immunogold-labeling than the perinuclear cytoplasm, relating IF of the vimentin type to dendrite formation and/or function. The method described is an appropriate tool for immunoelectron microscopic studies of IF of the vimentin type in situ.
Humans↗
Cyclosporin A in combination with photochemotherapy (PUVA) in the treatment of psoriasis.
Forty patients with relapsing plaque psoriasis involving more than 20% body surface were treated either with cyclosporin A (CyA) plus PUVA or the retinoid etretinate plus PUVA (RePUVA). They initially received either CyA (2 weeks) or etretinate (1 week) alone and then PUVA was given concomitantly until complete remission. The patients were monitored over a period of 6 months and any relapse recorded. With each combined treatment regimen, CyA plus PUVA and RePUVA, the patients cleared within comparable periods of time (mean treatment period of 5.3 vs. 4.7 weeks after initiation of therapy and 3.3 vs. 3.7 weeks after initiation of PUVA). However, the cumulative UVA dose required for clearance (110.9 J/cm2 vs. 62.1 J/cm2 (P less than 0.05)) and the incidence of severe and early relapses were significantly higher in the CyA cohort. Within 6 months severe relapses had occurred in 58% of CyA plus PUVA but only in 15% of RePUVA-treated patients (P less than 0.001). This suggests that the CyA plus PUVA regimen as performed in this study is less effective than RePUVA.
Adult↗
Side-effects of psoralen photochemotherapy (PUVA).
Although psoralen photochemotherapy (PUVA) is one of the most effective forms of therapy for psoriasis, the risk of potential long-term side-effects is, as yet, not clearly determined. Chronic degenerative and pigmentary skin changes similar to those of chronic solar exposure occur after long-term PUVA treatment; PUVA also causes non-melanoma skin cancers in man, although there is, as yet, no consensus as to what cumulative phototoxic PUVA dose is carcinogenic. Long-term multicentre studies from the U.S.A. indicate a definite risk of squamous cell carcinoma for long-term PUVA-treated patients, whereas European studies reveal no overall increase in skin cancers in similar patients except for those exposed to other carcinogens. Assignment to PUVA should be based on the risk:benefit ratio for the individual patient. Careful patient selection is therefore mandatory and should be limited to those who can be monitored and controlled by informed, competent and conscientious physicians.
Cataract↗
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↗
Treatment of psoriatic arthritis by extracorporeal photochemotherapy.
Five patients with long-standing seronegative arthritis resistant to conventional therapy and who also had psoriasis of the skin were treated with photopheresis. This mode of treatment combines a lymphocyte-enrichment procedure with 8-methoxypsoralen-photochemotherapy. There was a marked in vitro effect on treated lymphocytes, with a reduction of viability, proliferation and mitogen response. There was a slight to moderate clinical improvement in four of the five patients with regard to the strength of grip, swelling, pain, morning stiffness, the dosage of non-steroidal anti-rheumatic drugs and the radiographical changes. The skin lesions did not respond to photopheresis. Short-term side-effects were minimal and consisted of a temporary sensitivity of the eyes to light and signs of circulatory dysregulation immediately after treatment. This experimental therapy has some measurable but not dramatic effect in improving psoriatic arthropathy.
Adult↗
Maternal and fetal levels of a novel polypeptide, endothelin: evidence for release during pregnancy and delivery.
The occurrence of endothelin (ET), a recently discovered polypeptide with potent vasoconstrictor properties, was studied in maternal and umbilical blood and amniotic fluid. The level of ET-like immunoreactivity (ET-LI) in maternal plasma was in most cases below the detection limit of the radioimunoassay, i.e. less than 2 pmol/l. The median concentration of ET-LI in the umbilical artery and vein before the initiation of breathing was 14.9 and 10.9 pmol/l, respectively. When sampling was performed after fetal breathing had begun, the arterial concentration increased to 93.7 pmol/l. Labor was not associated with increased concentrations of ET-LI, however, since neonates delivered by elective cesarean section had similar ET-LI in blood and amniotic fluid as after vaginal delivery. An approximately fivefold increase in the amniotic fluid ET-LI was seen at term as compared to early mid-trimester values. Reversed phase HPLC characterization revealed that the observed ET-LI mainly corresponded to ET-1. It is suggested that ET-1 may contribute to the fetal hemodynamic changes, e.g., closure of the umbilical vessels occurring at delivery.
Amniotic Fluid↗
A rapid horizontal TLC method for detecting drugs of abuse.
We present a rapid, low-cost method for detecting opioids, cocaine and amphetamine in the urine of drug abusers. Rapid solid phase extraction of 2 mL of urine using octadecylsilane cartridges (Bond Elut C18) concentrates compounds of interest (including the polar metabolite of cocaine, benzoylecgonine), in a small volume of methanol, which is easily dried down. Four microlitres of aliquots of samples and standards are spotted on to 5 cm square polyester-backed silica gel plates, and developed (8-10 min) in a Desaga H-Chamber. Rf values of all relevant compounds are presented for two mobile phases using an iodoplatinate spray. The sensitivity of the method is not the same for all drugs but is always at least 1 microgram/mL urine. A number of investigations can be performed on a single extract from 2 mL of urine including confirmatory tests using different solvent systems or sprays.
Amphetamine↗