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Biomedical subjects

N Haas

Publications and source records attributed to N Haas.

At least 91 records · Page 5Linked to original sources
PubMed1995

[Rudolf Virchow (1821-1902) and his contributions to dermatology].

The contribution of Rudolf Virchow to dermatology seems to have been forgotten, or present-day dermatologists are not aware of it. The present historical review is intended to show that Virchow's thoughts and the terminology created by him are still alive. The report encompasses a short biography, including Virchow's nonmedical activities. It starts with early experimental publications, which laid to the foundation for his fame, and with dermatological studies of his early period. This is followed by a detailed description of his contributions pertaining to dermatology in his largest work, "Cellular-pathology". Special mention is made of Virchow's lasting contributions to medical, and particularly dermatological, terminology. Finally, his historical studies, his later small publications on topics in dermatology, his pupils and scientific friends, and the social-political and anthropological activities of later years are discussed. Thus, a multifaceted picture is painted of a still modern pathologist who has influenced dermatology in multiple ways.

Dermatology↗
PubMed1995

[Annular elastolytic giant cell granuloma with a spontaneous healing tendency].

Annular elastolytic giant cell granuloma is mostly found in middle aged women in skin areas exposed to sunlight. Our 17-year-old female patient had a widespread reddish-brown lesion on the abdomen that met the histological criteria for annular elastolytic giant cell granuloma. However, the clinical findings and the localization were uncommon. UV light was excluded as a trigger. Other, still unknown, factors that might change antigenicity of elastic fibres must be considered. Spontaneous resolution suggests a transient influence of such factors. Differential diagnosis includes skin disorders with elastolysis; discrimination especially from mid-dermal elastolysis is not well defined.

Adolescent↗
PubMed1995

Subcutaneous granuloma annulare of the eyelid. A case report.

A rare case of subcutaneous granuloma annulare of the eyelid is reported. A diabetic patient developed a unilateral periorbital tumorous mass. Biopsy revealed subcutaneous palisading granuloma. By microscopy and immunohistology, other granulomatous reactions including necrobiosis lipoidica could be ruled out. Since treatment with dapsone was without effect, the tumor was surgically excised. The differential diagnosis and the literature are briefly discussed.

Adult↗
PubMed1995

Neonatal neutropenia in low birthweight premature infants.

Neutropenia, as defined by common reference values, occurs often in neonates. Its incidence, causes, and clinical consequences have not been studied extensively in premature neonates. Of 208 consecutive infants with birthweight up to 2000 g, 121 (58%) had neutropenia. Low gestational age and low birthweight correlated with the incidence of neutropenia. Less than half of the neutropenic episodes could be attributed to infections, the others were related to specific perinatal events and due to drug therapy or were of unknown cause. Neutropenia following treatment with certain antibiotics was the most common cause of neutropenia occurring after the second week of life. The high incidence of neutropenia in premature neonates raises questions about application of these reference ranges to low birthweight infants and suggests the need for new reference values.

Anti-Bacterial Agents↗
PubMed1995

Beta 2-integrins in different forms of urticaria.

As urticarial lesions involve tissue invasion by inflammatory cells, and as beta 2-integrins play a central part in adhesion of leucocytes to endothelia, allowing their migration into the tissues, we have explored the distribution and sequential expression of these molecules in tissue sections from different forms of urticaria. Prick test weals (of 10 min duration) to common inhalant allergens showed only a minor increase of CD18, whereas in a case of cold urticaria CD11b and CD18 molecules were increasingly upregulated within the first 30 min after elicitation of the lesions. Skin test sites in delayed pressure urticaria, and urticarial lesions (> 6 h duration) of acute and chronic recurrent urticaria also showed marked upregulation of CD11b and CD18, and to a lesser extent of CD11a, but this did not strongly correlate with the intensity of the mixed cellular infiltrate. Non-lesional skin showed expression of beta 2-integrins in chronic urticaria, delayed pressure urticaria, and less so in acute urticaria, suggesting generalized leucocyte activation. This analysis of integrins thus suggests an early and extensive involvement of these molecules in the pathological events associated with the evolution of urticarial lesions.

Acute Disease↗
PubMed1995

Expression of stem cell factor in cutaneous mastocytosis.

Stem cell factor has recently been identified as a potent growth factor for bone marrow stem cells, melanocytes and mast cells. In order to evaluate its possible role in human mastocytosis, skin lesions from 13 patients with urticaria pigmentosa and five patients with mastocytomas, and normal skin specimens from five healthy donors were studied by immunohistochemistry, using polyclonal and monoclonal (hkl-12) antibodies against stem cell factor, and a monoclonal antibody (YB5.B8) against its receptor, the c-kit proto-oncogene product. Stem cell factor expression was noted in all sections studied, with an equal distribution pattern for both antibodies, but a weaker intensity with the hkl-12 reagent. Cytoplasmic staining was noted in keratinocytes, Langerhans cells, sweat gland ductal lining cells, mast cells, endothelial cells and spindle-shaped dermal stromal cells. An intense, diffusely granular reaction pattern was noted in all cells, except for a sparse, coarsely granular pattern in mast cells and stromal cells. In urticaria pigmentosa, staining was weaker in keratinocytes, but more prominent in Langerhans cells. In all sections, toluidine blue-positive mast cells and TA 99-positive basal epidermal melanocytes were the only cells to react with the c-kit antibody. Mastocytomas and urticaria pigmentosa lesions thus exhibit different patterns of stem cell factor expression. However, a possible pathogenetic role of this factor in mastocytosis remains to be determined.

Adolescent↗
PubMed1995

Two novel mast cell phenotypic markers, monoclonal antibodies Ki-MC1 and Ki-M1P, identify distinct mast cell subtypes.

In order to identify more specific or selective mast cell markers, the reactivity of two monoclonal antibodies, Ki-MC1 and Ki-M1P, was studied by immunohistochemistry in two human cell lines (mast cell line HMC-1, basophilic cell line KU812), in mast cells cultured from blood precursors, in adherent mononuclear cells from peripheral blood, and in mast cells of tissue sections from 13 urticaria pigmentosa lesions, five mastocytomas and five normal skin specimens. Toluidine blue staining, fluorescence staining with FITC-conjugated avidin, and immunohistochemical staining (APAAP) with other mast cell reactive monoclonal antibodies, was performed for comparison. Double staining with the APAAP method, using the Ki-antibodies and toluidine blue, was also carried out. Both Ki-antibodies showed reactivity for skin mast cells, but with a different staining pattern. In addition, the Ki-MC1 antibody did not react with the cell lines, and reacted only with a few peripheral blood mononuclear cells and cultured mast cells. In contrast, the Ki-M1P antibody reacted with almost all cultured mast cells and blood mononuclear cells, but stained only about one-half of lesional and one-fifth of normal skin mast cells. Ki-M1P also reacted with many toluidine blue-negative dermal cells, particularly in urticaria pigmentosa. Ki-MC1 antibody can thus be considered as a useful additional marker for normal skin mast cells. In contrast, the Ki-M1P antibody primarily identifies immature mast cells and monocytes/macrophages, suggesting that these cell types probably originate from the same bone marrow precursor.

Adult↗
PubMed1995

Expression of the c-kit receptor in hypomelanosis: a comparative study between piebaldism, naevus depigmentosus and vitiligo.

In order to investigate possible alterations in c-kit protein expression on epidermal melanocytes in different hypopigmentary disorders, we have examined skin specimens from one patient with piebaldism, one patient with naevus depigmentosus, and five patients with vitiligo. Cryosections were examined by immunohistochemistry using monoclonal antibodies against the c-kit protein (YB5.B8) and melanosomes (TA99). In piebaldism, hypomelanotic epidermis contained only a few TA99-positive epidermal melanocytes and no detectable c-kit protein, whereas in naevus depigmentosus the expression of c-kit protein was strong, and TA99 immunoreactivity was faint. In vitiligo lesions, no epidermal immunoreactivity for melanosomes or c-kit protein was found. Normally pigmented skin of all patients showed immunoreactivity of epidermal melanocytes for both c-kit protein and melanosomes. Different hypomelanotic lesions can thus be differentiated by absent melanocyte c-kit protein and low or no expression of melanosomal marker in piebaldism, normal c-kit but low melanosome expression in naevus depigmentosus, and the absence of all melanocyte markers in vitiligo.

Adult↗
PubMed1995

Interleukin-6 expression in the skin of patients with lupus erythematosus.

It has been proposed that interleukin-6 may play a role in the pathogenesis of autoimmune diseases like lupus erythematosus. We have therefore investigated the immunoreactivity of IL-6 in 32 skin biopsies of 23 patients suffering from chronic discoid lupus erythematosus (n = 16), subacute cutaneous lupus erythematosus (n = 5) and systemic lupus erythematosus (n = 5) as well as in uninvolved skin (n = 6) and in normal skin from healthy volunteers (n = 3). Increased immunohistochemical staining was detectable in 14 of 26 biopsies from lesional skin. The remaining biopsies from lesional, non-lesional and normal skin displayed only minimal or no reactivity, but 8 out of 12 lupus erythematosus patients had been pretreated with local or systemic antiinflammatory drugs. Irrespective of the LE subtype, immunolabelling was generally most intense in the basal layer of the epidermis, with additional intense suprabasal staining in sections from 2 of 5 SLE patients. Preferential production of IL-6 in the lower parts of the epidermis was confirmed by RNA in situ hybridization. No correlation was found between the deposition of immunoglobulins and complement at the dermo-epidermal junction and IL-6 expression in keratinocytes. These data suggest that IL-6 may be involved in LE although its exact role in the pathogenesis of the disease needs to be further elucidated.

Adult↗
PubMed1995

[Comparison of the diagnostic value of CT and MRI in injuries of the cervical vertebrae].

The aim of our study was to compare the diagnostic capacities of computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnostic evaluation of acute cervical spinal column injuries. We examined 39 patients with cervical spine injury suspected either clinically or by plain radiography, or even confirmed. In 30 patients, 86 acute traumatic lesions were observed in the area of the cervical spine, 83% of which were retrospectively recognisable by CT and 95% on MRI films. In nine patients, no acute traumatic pathologic pattern could be found either by CT or by MRI or any other subsequently employed diagnostic methods. CT yielded 100% of the osseous acute traumatic findings, the degenerative lesions narrowing the spinal channel, and of the dislocations, but only 33% of the lesions of the longitudinal ligaments, 50% of intramedullary haemorrhages, 60% of paravertebral soft tissue haematomas, 83% of vertebral disc herniations of protrusions, and none of the six nonhaemorrhagic spinal cord contusions. Without exception, MRI revealed all the traumatic medullary and paravertebral soft tissue changes, dislocations, and spondylophytes narrowing the spinal channel, but only 50% of the C2-odonteous fractures, 89% of the transverse processes', and 92% of the vertebral lamina fractures. Basing on these results, after primary plain film radiograph imaging, the performance of MRI seems to be recommendable prior to CT in diagnostic evaluation of traumatic cervical spinal lesions, if possible with regard to the patient's clinical state and the global organization, unless immediate CT imaging of other body regions (i.e. of the head) is already being planned anyway, Nevertheless, MRI should not be abandoned within the overally framework of this disease pattern.

Adult↗
PubMed1995

[Continuous cryotherapy--progress in therapy of post-traumatic and postoperative edema].

In patients with foot and ankle trauma, surgery and postoperative mobilization are often delayed owing to swelling. The aim of this study was to assess whether continuous cryotherapy is better than standard therapy with intermittently applied cool packs. For continuous cryotherapy the Polar Care Model 500 (BREG) was used. From May to November 1993, a series of 40 patient (22 ankle fractures, 13 ruptured lateral ankle ligaments, 4 calcaneus fractures, 1 metatarsal fracture) were prospectively randomized to continuous or intermittent cryotherapy. After 24 h treatment the patients with continuous cryotherapy showed an average reduction of 34% in swelling around ankle, midfoot and forefoot. With intermittent cryotherapy the swelling was reduced by 18%. After 4 days of treatment in the postoperative period the swelling subsided by 43% with intermittent cryotherapy, as against 69% with continuous cryotherapy. Continuous cryotherapy proved to be highly effective in treating posttraumatic and postoperative edema. It therefore seems preferable to the therapy with cool packs regarded as standard hitherto.

Adult↗
PubMed1995

[Diagnostic value and therapeutic consequences of computerized tomography (patient outcome research)--1: Diagnosis in traumatology].

During three months of 1993, 201 primary traumatologic patients (125 m, 76 f, x = 42.6 years) underwent 230 computed tomography examinations (= one CT of one body region) in the radiologic department of the Rudolf Virchow University Hospital. 87.0% of the CT's were performed completely without contrast media, 2.6% exclusively supported by intravenously given contrast media, 9.1% in both ways, and 1.3% after intra-articular contrast media administration. 97.4% served for primary diagnostic purposes and 2.6% for the control of therapeutic results. In 47.8% of the CT's, the principle diagnosis in the scanned body region was known before CT, i.e. by conventional X-ray examinations, but further detailed information was necessary to clarify the indication for operation and to choose the operative mode. In 52.2%, the diagnosis without CT was impossible by other, non-invasive and not more expensive methods. The CT diagnoses were correctly positive in 58.7% (suspected diagnosis verified, additional detail information...) and correctly negative in 41.3% (suspected diagnosis excluded). 60.9% of CT's demonstrated a missing indication for operation in the examined body region; in 39.1% the operation followed. The most frequently performed diagnostic methods before CT were conventional X-ray and sonography, whereas after CT further examinations were seldom needed. We conclude that traumatologic CT's contribute decisively to the reduction of costs by avoiding more expensive examination methods, avoiding redundant operations, and abridging stay duration in the hospital because of more efficient therapy planning.

Abscess↗
PubMed1995

The new unreamed AO nails for the tibia and the femur.

The advantages of the unreamed nailing technique compared to the reamed procedure are less damage to bone vascularity, lower intramedullary pressure during the operation and a fast operation time. These new solid nails with high mechanical stiffness and no central dead space have extended the nail indications for tibial as well as for femoral fractures, particularly in tibial shaft fractures with severe soft tissue damage and in polytraumatized patients with a femoral shaft fracture. Besides these advantages the new AO unreamed femur nail has a modular proximal interlocking system, which increases significantly the range of indications for nailing. Not only very high subtrochanteric femur fractures can be stabilized with greater stability, but also combined ipsilateral fractures of the shaft and the proximal femur can be treated with this new nail. The first clinical results of the AO unreamed nails for the tibia as well as for the femur are very encouraging. The unreamed nails prove to be excellent implants in the treatment of long bone fractures of the lower extremity.

Adult↗
PubMed1994

Phenotypic evaluation of cultured human mast and basophilic cells and of normal human skin mast cells.

In order to evaluate various markers for human mast cells, two human mast/basophilic cell lines (HMC-1/KU812), cultured mast cells from the peripheral blood monocytic fraction and peripheral blood monocytes were compared with mast cells in tissue sections from normal skin, using histochemistry, enzyme histochemistry and immunohistochemistry. All reagents stained normal skin mast cells, with toluidine blue, tryptase reactivity and antibodies against the Fc epsilon RI and the stem cell factor receptor (c-kit) being most active. The cell lines and mast cells cultured from peripheral blood were negative for avidin, safranin and chymase, strongly positive for c-kit and variably reactive with all other reagents. All antibodies except AA1 against tryptase also stained one or several epidermal and dermal cell types or blood monocytes. Histochemical stains (toluidine blue, avidin) and reagents for the enzymes tryptase and chymase are thus specific markers for mast cells. The frequent reactivity of antibodies against mast cells with other cell types indicates interesting functional and ontogenetic relationships between these cells.

Antibodies, Monoclonal↗
PubMed1994

[Localized Sweet syndrome].

A 73-year-old women developed an inflammatory tumor on her right cheek within 3 weeks. The lesion measured more than 7 cm in diameter, contained a central crateriform depression and was studded with several sterile pustules. Histology showed a dense dermal infiltration of neutrophils, but no leukocytoclasia or destruction of dermal tissue. There was no associated leukocytosis or fever, but the patient suffered from recurrent chronic bronchitis. Because the acute inflammation was progressive under treatment with antibiotics, high-dose corticosteroids were given systemically. The tumor regressed quickly and resolved without scarring. Although this localized Sweet's syndrome is unusual, it fulfills several major and minor criteria of Sweet's syndrome and thus represents a rare form of this disease.

Aged↗
PubMed1994

Routine application of the pinless external fixator.

One serious disadvantage of conventional fixator systems is the need to open the medullary space, hence creating a direct communication with the exterior. The new pinless external fixator does not have this major disadvantage, because the fixator clamps simply rest on the cortical bone without penetrating it. Clinically, this easily managed system is intended for fractures of the tibia in cases in which primary internal fixation is precluded either by precarious local or general conditions or by infrastructural problems. In such situations the new pinless fixator is an excellent device with which to achieve good stabilization of the fracture rapidly, while leaving open all options for subsequent alteration of treatment. If the surgeon decides to convert to locked intramedullary nailing, the pinless fixator facilitates the new approach, because it can be used as a distractor and makes it unnecessary to transfer the patient to a fracture table.

Adult↗