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M Schaller

Publications and source records attributed to M Schaller.

At least 73 records · Page 4Linked to original sources
PubMed1997

[Dorfman-Chanarin syndrome--a neutral lipid storage disease].

Dorfman-Chanarin syndrome is a rare, autosomal recessive inherited lipid storage disease with skin manifestations in form of congenital ichthyotic erythroderma. Demonstration of lipid vacuoles in neutrophils from peripherals blood smears in patients with ichthyotic erythroderma leads to the diagnosis. Other organ systems, such as CNS, liver, muscle, ears and eyes, are frequently involved. Since Dorfman-Chanarin syndrome may present with just skin findings, it should be included in the differential diagnosis of the congenital ichthyoses. Microscopic examination of peripheral blood smears is recommended in all patients with ichthyosis. We summarize the current data on the pathogenesis, diagnosis, differential diagnosis, and therapeutic options in Dorfman-Chanarin syndrome, give an overview of the clinical manifestations of the 23 patients affected with this rare disease.

Adolescent↗
PubMed1997

In-process cell counts during preparation of platelet concentrates from buffy coats.

To ensure the quality of platelet concentrates (PCs), we studied in-process recoveries of blood cell counts in pooled PCs derived from four or five buffy coats (BCs) from Biopack Compoflex Systems in Bern (PC-BC/4 or PC-BC/5) and from five BCs from Optipac (Baxter) in Zurich (PC-BC/5). BCs were pooled employing a sterile connecting device and flushing them with 300 mL of platelet additive solution. The pools were centrifuged for 12 min at 500 g at 20 degrees C and filtered with PALL's Auto-Stop BC-leukocyte removal filter. Automated platelet counting was performed on whole blood donation, on single BC, on pooled BC and in the final product. Four out of 10 PC-BC/4 (= 40%) and 29 out of 30 PC-BC/5 (= 97%) had a total platelet count of > 200 x 10(9) platelets. Average percentage recoveries in PC compared to the pre-centrifugation BC pools were similar with the Biopack Compoflex and the Optipac systems, 62% and 57% respectively, whereby the absolute platelet count per one donation was similar, i.e. 49.5 x 10(9), 55 x 10(9) and 53 x 10(9) in PC-BC/4 and PC-BC/5 from Bern and PC-BC/5 from Zurich. There was a significant positive correlation between the inital number of BCs taken for pooling and the final platelet counts in the PCs. In order to recover a minimal platelet content of 200 x 10(9) platelets per pooled unit, it is safer to start out with five rather than with four donations unless recoveries during the production steps can be improved.

Blood Cell Count↗
PubMed1997

Chronic ulcerative stomatitis.

Chronic ulcerative stomatitis (CUS) has recently been described as a new disease entity characterized by chronic ulceration of oral mucosa which responds to treatment with hydroxychloroquine. It has a particular type of stratified epithelium-specific, antinuclear autoantibody as an immunological marker. Twelve cases have been reported in the literature. We present a 40-year-old woman with an 11-year history of chronic oral ulcerations. Other dermatological diseases, including oral lichen planus, pemphigus vulgaris and cicatricial pemphigoid, as well as bullous lupus erythematosus, were excluded. The clinical diagnosis of CUS was confirmed on the grounds of the immunological and ultrastructural findings. The lesions initially responded to high doses of systemic corticosteroids but relapsed promptly after dose reduction. Dapsone was ineffective. Hydroxychloroquine, given at a dosage of 200-400 mg/day, led to a complete and long-lasting remission.

Adult↗
PubMed1997

Direct evidence for uptake of intact liposomes encapsulating silver sulfadiazine by cultured human keratinocytes based on combined transmission electron microscopy and X-ray microanalysis.

Cultured human keratinocytes were exposed to liposomally encapsulated silver sulfadiazine, free silver sulfadiazine, silver sulfadiazine cream, and a corresponding vehicle for 5 min to 24 h. Phagocytosis of intact liposomes by keratinocytes was demonstrated in vitro by combined X-ray microanalysis and electron microscopy. Silver as an active part of the antimicrobial served as an electron-dense marker.

Anti-Infective Agents, Local↗
PubMed1997

Light and electron microscopic findings in human epidermis reconstructed in vitro upon topical application of liposomal tretinoin.

The topical application of tretinoin is a well-established approach to the treatment of acne vulgaris. However, induced inflammation, clinically addressed as a "flare-up", is a major drawback. Recently, clinical and experimental investigations have hinted at a better tolerability, with equal efficacy, if the active compound is liposomally encapsulated. Using epidermis reconstructed in vitro, we compared the morphological changes upon topical application of a liposomal form (0.05% and 0.025%) and conventional form (0.05%) light and electron microscopically. After 24 h several remarkable changes of the stratum corneum with all treatment modalities, representing inhibition of keratinisation wanted in acne vulgaris, were seen. When preparations of equal strength, i.e. 0.05%, were compared, the changes representing toxic dermatitis in the epidermis were more marked with the conventional form. Epidermis reconstructed in vitro treated with the liposomal forms showed no significant differences due to either concentration. It is suggested that these changes correspond to the flare-up on clinical grounds. The in vitro findings further corroborate the hypothesis that liposomal encapsulation can increase the benefit/risk ratio of an active compound applied to the skin.

Administration, Topical↗
PubMed1997

Molecular diagnosis of deep nodular bacillary angiomatosis and monitoring of therapeutic success.

A 51-year-old human immunodeficiency virus (HIV)-positive male patient (CDC stage 3C) had had a painful nodule on his external ankle joint for 10 months. A biopsy suggested bacillary angiomatosis, but Kaposi's sarcoma could not be excluded. Rods were detectable in lesional skin by a Warthin-Starry stain. A 298 base pair (bp) gene fragment specific for Bartonella species was amplified from lesional skin and direct nucleotide sequence analysis of the amplification product clearly identified Bartonella quintana. Kaposi's sarcoma-associated herpes virus specific DNA was not amplifiable by polymerase chain reaction (PCR) in our patient, suggesting that the lesion represented bacillary angiomatosis alone, despite clinical and histopathological features which suggested the coexistence of bacillary angiomatosis and Kaposi's sarcoma. The lesion regressed after erythromycin was prescribed. However, 4 and 9 weeks after initiation of therapy, PCR still yielded a positive result in material obtained by a swab. After complete healing, following 12 weeks of antibiotic therapy, PCR became consistently negative. The optimal length of antibiotic treatment in HIV-positive patients with bacillary angiomatosis is not yet known and inadequate therapy may be followed by disseminated disease and a fatal outcome. PCR-based monitoring of the success of treatment is valuable for determining the duration of treatment resulting in a cure.

AIDS-Related Opportunistic Infections↗
PubMed1996

The hyperkeratotic variant of porokeratosis Mibelli is a distinct entity: clinical and ultrastructural evidence.

An isolated case with the hyperkeratotic variant of porokeratosis Mibelli (PM) is reported. The 62-year-old woman developed multiple brown macules with well demarcated large keratotic nodules on both legs. Histopathological studies revealed the presence of a cornoid lamella characteristic of porokeratosis. Ultrastructural investigations revealed dyskeratotic as well as edematous, swollen keratinocytes; autophagocytotic vacuoles were visible. The clinical and ultrastructural peculiarities of the hyperkeratotic variant of PM suggest the possibility of a separate entity.

Administration, Topical↗
PubMed1996

Multiple keratoacanthomas, giant keratoacanthoma and keratoacanthoma centrifugum marginatum: development in a single patient and treatment with oral isotretinoin.

A 78-year-old man is described, who over 18 years developed three different types of keratoacanthoma: multiple keratoacanthomas, keratoacanthoma centrifugum marginatum and giant keratoacanthoma. Histological examination of the different neoplasms showed similar changes, all typical of a keratoacanthoma. In situ hybridisation revealed no human papilloma virus in the tumours. Complete examination showed no associated internal malignancy. After repeated surgical treatment oral isotretinoin treatment was administered (1 mg/kg per day). This treatment produced clearing of existing keratoacanthomas and, during a period of 2 months, further keratoacanthoma formation was completely suppressed. Treatment was stopped after 3 months by the patient because of side-effects. Numerous keratoacanthomas developed during the following 6 weeks.

Administration, Oral↗
PubMed1996

Interaction of cultured human keratinocytes with liposomes encapsulating silver sulphadiazine: proof of the uptake of intact vesicles.

There is evidence to suggest that human keratinocytes grown in vitro are capable of engulfing and subsequently disintegrating intact liposomes. However, as the liposomes used in this context did not carry an electron-dense marker, the possibility that the lamellar structures seen within the keratinocytes were composed of material produced within the cell could not be excluded. We therefore decided to investigate liposome-keratinocyte interaction using an electron-dense marker. Human keratinocytes obtained from juvenile foreskins were cultured in a serum-free medium, and subconfluent cultures were exposed to liposomally encapsulated and free silver sulphadiazine 1% (SSD), and a corresponding vehicle, for 5 min to 24 h. After fixation ultra-thin sections were analysed electron microscopically at magnifications of up to x85,000. Many keratinocytes treated with liposomal and free SSD showed marked damage to the plasma membranes and the cell organelles. The phagocytosis of intact liposomes was demonstrated by the appearance of silver-labelled unilamellar vesicles within the cytoplasm of undamaged keratinocytes. The labelled liposomes were found enclosed in cellular unit membranes, i.e. in lysosomes. In addition, perinuclear disintegration and release of the entrapped marker were observed. Silver particles, as present in liposomally encapsulated SSD, were found to be adequate markers for electron microscopy. Our results confirm the phagocytosis of intact liposomes by keratinocytes in vitro. In addition, the cytotoxic effects of liposomal (intended for the treatment of burns) and free SSD on human keratinocytes were studied in detail. Many keratinocytes treated for 10 min or more were severely affected.

Cells, Cultured↗
PubMed1995

Allergic airborne contact dermatitis from essential oils used in aromatherapy.

Contact allergy to various essential oils used in aromatherapy was demonstrated on patch testing in a 53-year-old patient suffering from relapsing eczema resistant to therapy on various uncovered parts of the skin, in particular the scalp, neck and hands. Sensitization was due to previous exposure to lavender, jasmine and rosewood. Laurel, eucalyptus and pomerance also produced positive tests, although there was no hint of previous exposure. A diagnosis of allergic airborne contact dermatitis was thus established. On topical and systemic glucocorticoid treatment (peroral methylprednisolone at an initial dose of 60 mg/day) the skin lesions eventually resolved. Due to persistence of the volatile essential oils in the patient's home after a year-long use of aroma lamps, complete renewal of the interior of the patient's flat was considered essential. Due to changing self-medication habits, with increasing orientation to 'natural' modes of treatment, increasing numbers of such sensitizations might be on the horizon.

Air Pollutants↗
PubMed1994

[The immotile cilia syndrome. A rare form of male infertility].

A man presented with 100% immotile spermatozoa. Transmission electron microscopy showed the absence of both central tubules in all sperm tails; the nine peripheral tubules, dynein arms, radial spokes and other structures of the sperm tail were normal. Immotile cilia syndrome of the 9 + 0 tubular pattern was diagnosed. Other anomalies frequently associated with immotile cilia syndrome, such as recurrent airway infections, bronchiectases and situs inversus (Kartagener's syndrome), were not present in this case.

Adult↗
PubMed1993

Bacteriophages induced by ciprofloxacin in a Borrelia burgdorferi skin isolate.

Two types of tailed bacteriophages were detected by electron microscopy in a Borrelia burgdorferi strain which had been isolated from infected human skin and exposed to the gyrase inhibitor ciprofloxacin. One of these phages displayed an isometric 30 nm head, a neck and a contractile tail 50-64 nm in length with a baseplate, according to an A-1 morphology. The other phage showing a B-1 morphology had a 30 nm isometric head as well and a long non-contractile straight tail 115-130 nm in length without neck and baseplate. Both types of phages could be found together within one plasmolysed spirochetal cell. We conclude that we are dealing with a lysogenic strain of Borrelia burgdorferi carrying at least two different prophages inducible by ciprofloxacin.

Adult↗
PubMed1992

Cell adhesion or integrin clustering increases phosphorylation of a focal adhesion-associated tyrosine kinase.

We have recently shown that changes in tyrosine phosphorylation of a 130-kDa protein(s) (pp130) may be involved in integrin signaling (Kornberg, L., Earp, H.S., Turner, C., Prokop, and Juliano, R. L. (1991) Proc. Natl. Acad. Sci. U.S.A. 88, 8392-8396). One component of the pp130 protein complex reacts with an antibody generated against p125fak, which is a focal contact-associated tyrosine kinase (Schaller, M.D., Borgman, C. A., Cobb, B. S., Vines, R. R., Reynolds, A. B., and Parsons, J. T. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 5192-5196). Both antibody-mediated integrin clustering and adhesion of KB cells to fibronectin leads to increased tyrosine phosphorylation of p125fak. The phosphorylation of p125fak is coincident with adhesion of cells to fibronectin and is maximal prior to cell spreading. Tyrosine phosphorylation of p125fak is induced when KB cells are allowed to adhere to fibronectin, collagen type IV, or laminin, but is not induced on polylysine. When KB cells are subjected to indirect immunofluorescence microscopy, p125fak colocalizes with talin in focal contacts. These data provide additional evidence that tyrosine kinases are involved in integrin signaling.

Animals↗
PubMed1992

Expression of the neu protooncogene in the mammary epithelium of transgenic mice induces metastatic disease.

Overexpression and amplification of the neu (c-erbB2, ERBB2) protooncogene have been implicated in the development of aggressive human breast cancer. To directly assess the effect of mammary gland-specific expression of the neu protooncogene, transgenic mice carrying unactivated neu under the transcriptional control of the mouse mammary tumor virus promoter/enhancer were established. By contrast to the rapid tumor progression observed in several transgenic strains carrying the activated neu transgene, expression of unactivated neu in the mammary epithelium resulted in the development of focal mammary tumors after long latency. The majority of the mammary tumors analyzed expressed elevated levels of neu-encoded mRNA and protein. Overexpression of neu in the mammary tumors was also associated with elevated neu intrinsic tyrosine kinase activity and the de novo tyrosine phosphorylation of several cellular proteins. Interestingly, many of the tumor-bearing transgenic mice developed secondary metastatic tumors in the lung. These observations suggest that overexpression of the unactivated neu protein can induce metastatic disease after long latency.

Animals↗
PubMed1991

The relations of parental characteristics and practices to children's vicarious emotional responding.

We examined the relation of parental empathy-related characteristics and emotion-related child-rearing practices to third and sixth graders' vicarious emotional responding. Children's heart rate, skin conductance, facial, and self-reported reactions to a sympathy-inducing film were assessed, as were their dispositional sympathy, empathy, and self-monitoring. Parental sympathy was positively related to low levels of personal distress in same-sex children and, for both parents, with sons' dispositional sympathy or empathy. Parental emphasis on problem-focused coping strategies when their sons were anxious was positively correlated with indexes of sons' situational and dispositional sympathy. Same-sex parental restrictiveness in regard to the control of inappropriate, hurtful emotional displays was associated with sons' and daughters' dispositional and situational sympathy, whereas maternal restrictiveness in regard to emotions that are unlikely to hurt others was correlated with nonverbal indexes of personal distress and self reports of low distress. Parental emphasis on control of the child's own negative emotion was associated with children's self-monitoring.

Arousal↗
PubMed1991

Personality and socialization correlates of vicarious emotional responding.

The relations of personality and family characteristics to adults' negative vicarious emotional responses to sympathy and distress films were examined. Ss reported more sympathy and less personal distress and exhibited less skin conductance as well as heart rate deceleration when viewing a sympathy-evoking film. Dispositional emotional intensity and fantasy empathy were associated with greater self-reported emotional responding and higher skin conductance. Dispositional perspective taking and personal distress were positively and negatively correlated, respectively, with reported vicarious responding to the sympathy film when Ss were administered instructions to imagine the emotions of those in the films. Family cohesiveness was associated with reported sympathy and sadness in reaction to the sympathy film, whereas the expression of negative subordinate and positive emotional states in the home of origin was associated with women's reported responsivity.

Adult↗
PubMed1989

Sympathy and personal distress: development, gender differences, and interrelations of indexes.

In summary, in our multimethod research concerning vicariously induced emotion, we have obtained several patterns of importance. First, we have obtained modest differences in facial and self-report indexes of emotion, nearly all indicating greater responsivity by females. Moreover, some of the data suggest that this gender difference increases with age. Second, we have found that facial indexes of negative emotion are stronger for younger than older persons and that older children's self-reports of emotion are somewhat more consistent with the context than are those of young children. Finally, although we have not obtained strong or consistent relations among our physiological, self-report, and facial indexes of emotion, those that have been obtained suggest a positive relation among indexes, one that appears to be stronger for younger than older persons (especially girls). Further research confirming these patterns of findings is needed; nonetheless, the preliminary data can be viewed as indicating that a multimethod approach to studying empathy is useful for increasing our understanding of empathy, sympathy, and personal distress reactions and their development.

Age Factors↗