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Biomedical subjects

C Hauser

Publications and source records attributed to C Hauser.

At least 55 records · Page 3Linked to original sources
PubMed1999

The mucosal adhesion receptor alpha4beta7 integrin is selectively increased in lymphocytes stimulated with beta-lactoglobulin in children allergic to cow's milk.

BACKGROUND: It has been shown in mice that the integrin alpha4beta7 directs the migration of memory T cells into the gut-associated lymphoid tissue. However, little is known about T-cell homing mechanisms in children with food allergies. OBJECTIVE: We investigated the expression of this and other integrins in children with different manifestations of cow's milk allergy (urticaria, atopic dermatitis, and wheezing). METHODS: PBMCs were stimulated with beta-lactoglobulin, 1 of the major allergenic proteins in cow's milk, and tetanus toxoid. Integrin expression was studied by flow cytometric analysis after 1 week of culture. RESULTS: We found significantly higher expression of the alpha4beta7 integrin in cells from patients compared with control subjects with no allergies (P =. 005) when beta-lactoglobulin was used to stimulate the cells. alpha4beta7 integrin was also expressed at significantly higher levels in beta-lactoglobulin-stimulated cells than in tetanus toxoid-stimulated cells (P =.005). The alphaEbeta7 and the alpha4beta1 integrins were not upregulated by allergen stimulation. Most alpha4beta7 integrin-expressing cells were identified as CD4(+) T cells. CONCLUSION: These results show that alpha4beta7 integrin expression after stimulation with beta-lactoglobulin correlates with the presumptive site of cow's milk sensitization (ie, the gut-associated lymphoid tissue but not with the site of symptoms of cow's milk allergy).

CD4-Positive T-Lymphocytes↗
PubMed1999

Rescue of the cardiac defect in ErbB2 mutant mice reveals essential roles of ErbB2 in peripheral nervous system development.

ErbB2 receptor tyrosine kinase plays a role in neuregulin signaling and is expressed in the developing nervous system. We genetically rescued the cardiac defect of erbB2 null mutant embryos, which otherwise died at E11. These rescued erbB2 mutant mice die at birth and display a severe loss of both motor and sensory neurons. Motor and sensory axons are severely defasciculated and aberrantly projected within their final target tissues. Schwann cells are completely absent in the peripheral nerves. Schwann cell precursors are present within the DRG and proliferate normally, but their ability to migrate is decreased. Acetylcholine receptors cluster within the central band of the mutant diaphragm muscle. However, these clusters are dispersed and morphologically different from those in control muscle. Our results reveal an important role for erbB2 during normal peripheral nervous system development.

Animals↗
PubMed1999

Facial dermatitis, contact urticaria, rhinoconjunctivitis, and asthma induced by potato.

BACKGROUND: Potato contains multiple heat-labile proteins which can induce immediate hypersensitivity reactions. Rhino-conjunctivitis, asthma, contact urticaria and protein contact dermatitis have been described in association with potato exposure. OBJECTIVE: A patient with possible airborne facial dermatitis to potato is described. RESULTS: A middle-aged atopic housewife with pre-existent atopic dermatitis suffered from rhino-conjunctivitis, asthma, and contact urticaria when pealing raw potatoes, but her main complaint was intense, treatment-resistant dermatitis of the face. The investigations showed a positive prick test, a positive patch test, and positive specific serum IgE to raw potato. Potato avoidance led not only to the resolution of the immediate symptoms, but also of the facial dermatitis, suggesting she had dermatitis due to this vegetable. CONCLUSIONS: Potato may induce contact dermatitis with positive immediate and delayed hypersensitivity tests.

Asthma↗
PubMed1999

Factors influencing changes in maxillary arch dimensions in unilateral cleft lip and palate patients until six months of age.

OBJECTIVE: The objectives of the present study were (1) to investigate whether growth increments until 6 months of age are influenced by particular factors, (2) to analyze whether anterior cleft reduction is dependent on the extent of the cleft width at birth, and (3) to examine the correlation between maxillary measurements at birth and the anterior cleft width at 6 months of age. DESIGN: The study design was prospective and longitudinal. SETTING: Heidelberg University Hospital Interdisciplinary Cleft/Craniofacial Center. PATIENTS AND METHOD: The longitudinal records of 34 patients (24 male and 10 female) with complete unilateral cleft lip, alveolar ridge, and hard and soft palate were included in this study. All patients were treated with the same protocol. All participants were assessed at 0 and 6 months of age. Maxillary plaster casts of the patients were analyzed using a computer-controlled three-dimensional digitizing system. MAIN OUTCOME MEASURE: Maxillary models were measured and compared to putative factors influencing growth. RESULTS: No statistically significant differences were found between maxillary growth changes and increases in weight and length. Similarly, there was no significant interaction between the extent of the alveolar cleft width at birth and its reduction prior to lip closure. In contrast, significant differences of maxillary growth increments could be found between male and female patients. Stepwise regression analysis demonstrated a correlation between maxillary measurements at birth and growth increments. CONCLUSION: The results of the study indicate that gender plays a certain role in growth changes within the first 6 months of age.

Aging↗
PubMed1999

[Cardiac fibrosarcoma discovered by cerebral metastases].

Primary heart tumors are rare, and the fibrosarcomas are exceptional. We present the findings in a 78 year old female who has been hospitalized in April 1997 with a history of 4 months of malaise, headaches and weight loss. Clinical examination showed a right lateral homonymous hemi-anopsia. Computed tomography (CT-Scan) of the brain showed two lesions in the occipital and temporal lobe, consistent with metastasis. Thoracic and abdominal-pelvic CT-Scan revealed a voluminous mass of the left auricle that has been interpreted as a probable sarcoma. Biopsy specimen of one of the cerebral lesions, performed at the Centre hospitalier universitaire vaudois (CHUV) on April 29th 1997, revealed fragments of a poorly differentiated sarcoma. After referral back to Neuchâtel, the patient suffered suddenly three weeks later from a cerebral vascular insult with instant onset of deep coma. She deceased on May 27. At autopsy we found a neoplastic lesion of the left auricle with invasion of the pulmonary veins. The histological appearance is similar to the appearance of the cerebral metastasis, showing a proliferation of spindled cells with a partial positivity for Vimentine. It was classified as a fibrosarcoma. Metastasis were found only in the brain with postoperative ischemic left occipitotemporal necrosis and neoplastic emboli.--We are discussing the various incidences of cardiac neoplasms in autopsies or biopsies.

Aged↗
PubMed1998

Anaphylaxis to parenteral thiamine (vitamin B1).

Anaphylaxis as an adverse systemic reaction to thiamine (vitamin B1) has been described in the literature since 1938. Although its precise mechanism is still uncertain, the reaction appears to involve immediate type hypersensitivity and to be exclusively related to parenteral administration. The following case report is a reminder of this reaction to thiamine which may be administered by general practitioners, emergency physicians and internists.

Adult↗
PubMed1998

Severe anaphylaxis to a new disinfectant: polyhexanide, a chlorhexidine polymer.

We describe the cases of an 18-year-old female and a 15-year-old male who developed severe anaphylaxis following contact of surgical wounds with the disinfectant Lavasept, containing polyhexanide, a polymerised form of chlorhexidine, during orthopaedic interventions. According to the manufacturer, this product is the only polyhexanide containing medical disinfectant, has recently been commercialised and is only available in Switzerland. One of the patients denied previous contact with this compound but both patients were previously exposed to chlorhexidine. Immediate-type hypersensitivity to polyhexanide was suggested by positive skin prick tests in the two patients and by negative skin tests in control individuals. Skin tests with chlorhexidine in the patients remained negative. We conclude that contact with the new disinfectant Lavasept can trigger anaphylactic reactions, even in the absence of previous history of exposure to this compound. It remains to be established whether this new disinfectant is a frequent anaphylactogen.

Administration, Topical↗
PubMed1998

[The problem of hidden food allergens: two cases of anaphylaxis to peanut proteins concealed in a pizza sauce].

Peanut is one of the major food allergens inducing anaphylaxis. It is increasingly consumed and often used as a hidden ingredient, thus making avoidance especially difficult for allergic patients. In Switzerland legislation stipulates that all ingredients of a processed food exceeding 2% of the total mass of the finished food product should be labelled. However, in the case of a mixture of vegetables it can be labelled as "vegetable mix" if it does not exceed 10% of the total weight. Peanut, which is a member of the legume family, can thus form up to 10% of processed foods without being mentioned on the label, thus making avoidance impossible. We report on two patients who presented severe anaphylaxis from peanut hidden in a pizza from a fast food restaurant. We were able to provide evidence for the presence of major peanut antigens in the pizza sauce by immunochemical analysis. These two cases clearly demonstrate the danger of peanut hidden in foods and point up the necessity of a change in legislation.

Adolescent↗
PubMed1998

Corticotropin releasing factor receptor 1-deficient mice display decreased anxiety, impaired stress response, and aberrant neuroendocrine development.

Corticotropin releasing factor (CRF) is a major integrator of adaptive responses to stress. Two biochemically and pharmacologically distinct CRF receptor subtypes (CRFR1 and CRFR2) have been described. We have generated mice null for the CRFR1 gene to elucidate the specific developmental and physiological roles of CRF receptor mediated pathways. Behavioral analyses revealed that mice lacking CRFR1 displayed markedly reduced anxiety. Mutant mice also failed to exhibit the characteristic hormonal response to stress due to a disruption of the hypothalamic-pituitary-adrenal (HPA) axis. Homozygous mutant mice derived from crossing heterozygotes displayed low plasma corticosterone concentrations resulting from a marked agenesis of the zona fasciculata region of the adrenal gland. The offspring from homozygote crosses died within 48 hr after birth due to a pronounced lung dysplasia. The adrenal agenesis in mutant animals was attributed to insufficient adrenocorticotropic hormone (ACTH) production during the neonatal period and was rescued by ACTH replacement. These results suggest that CRFR1 plays an important role both in the development of a functional HPA axis and in mediating behavioral changes associated with anxiety.

Adaptation, Physiological↗
PubMed1998

Ethanol-induced urticaria: elevated tryptase levels after double-blind, placebo-controlled challenge.

We present a 48-year-old patient who complained for 1 year about urticarial reactions which appeared always when he ingested alcoholic beverages. Skin prick tests with ethanol were negative but positive with 10% acetic acid in the patient. Normal controls tested negative with acetic acid. Skin prick tests to common immediate-type allergens were negative. The patient underwent a double-blind, placebo-controlled challenge test. A few minutes after challenge with ethanol but not with placebo, the patient developed erythema and wheals on the chest and the upper arms. The tryptase serum level rose from undetectable (0.1 U/ml) before challenge to 3.8 U/ml after skin lesions had appeared. This case demonstrates that increased tryptase serum levels can help in the diagnosis of ethanol-induced urticaria.

Alcoholic Beverages↗
PubMed1997

Transformed and nontransformed human T lymphocytes migrate to skin in a chimeric human skin/SCID mouse model.

To study human T cell migration to human skin in vivo, we grafted severe combined immunodeficient mice with 500-microm thick human skin. Two weeks after grafting, epidermal and dermal structures in the grafts were of human origin. When we intraperitoneally injected grafted mice with clones of the human HUT-78 T cell line derived from a patient with cutaneous T cell lymphoma and Sézary syndrome, we detected in the grafts the rare Vbeta23-Jbeta1.2 T cell receptor transcripts characteristic for the HUT-78 clones. These signals were found 2-6 d after cell injection in about 40% of the grafted and HUT-78 cell injected mice but not in grafts from mice that received no exogenous T cells. In contrast to HUT-78 cells, which only accumulate in low number, grafts topically challenged with nickel sufate in vaseline from mice that were injected with autologous nickel-reactive T cell lines led to massive accumulation of T cells within 3 d. Only scattered T cells accumulated in the skin when grafted mice received vaseline plus T cells, nickel sulfate alone, T cells alone, or nickel sulfate plus an allogeneic nickel-nonreactive T cell clone. When the T cell lines were labeled with the fluorochrome PKH-26 before cell injection, spots of fluorescent label in the size and shape of cells were found in the grafts challenged with nickel. Together, these results clearly demonstrate that human T cells can migrate to human skin in this chimeric human/mouse model.

Animals↗