Biomedical subjects

A Brandis

Publications and source records attributed to A Brandis.

At least 37 records · Page 2Linked to original sources

PubMed1997

[Primary intra-meatal invasion of meningioma into the left meatus acusticus internal in a 49-year-old woman].

BACKGROUND: Meningiomas originating in the internal auditory meatus are rare and have been reported in only 12 cases. PATIENT: We report about another case, which showed primarily the symptoms of sudden hearing loss and diagnostic signs of an intrameatal acoustic neuroma. The ABR interpeak latency IV was prolonged. The tumor was detected by MRI scan with gadolinium contrast enhancement and resembled the features of an intrameatal acoustic neuroma. RESULTS: The tumor was removed via a middle fossa approach with preservation of hearing and facial nerve function. Histological examination however revealed a meningioma originating from the internal auditory meatus. CONCLUSIONS: Contrast enhancing intrameatal tumors are most often acoustic neuromas. However even despite subtile audiological and neurotological examination and sophisticated imaging techniques they cannot be differentiated clinically from meningiomas at this location. Removal of the intrameatal tumor via a middle fossa approach seems to be the best surgical approach to preserve hearing and facial nerve function.

Audiometry, Pure-Tone↗

PubMed1997

Protein-A-mediated targeting of bacteriochlorophyll-IgG to Staphylococcus aureus: a model for enhanced site-specific photocytotoxicity.

A model for studying the efficiency of photodynamic action with a photosensitizer placed exclusively on the bacterial cell wall has been used. Bacteriochlorophyllide molecules, conjugated to rabbit immunoglobulin G (IgG), were synthesized. The conjugated pigment bacteriochlorophyll (Bchl)-IgG bound with high specificity to protein-A residues naturally exposed on the cell wall of the bacterium Staphylococcus aureus Cowan I. In bacterial suspensions the phototoxicity of the targeted conjugates (0.5-2.5 pigment per IgG molecule) was dose dependent (LD50 = 1.7 microM) in the presence of light (lambda > 550 nm) and inhibited by native IgG but not by ovalbumin, suggesting selective interaction with protein-A on the bacterial cell wall. No dark toxicity was noticed even with the highest conjugate concentration tested. In contrast, the photocytotoxicity of bacteriochlorophyll-serine (Bchl-Ser, LD50 = 0.07 microM) used as a nontargeted control was not inhibited by IgG. In spite of its lower apparent potency, Bchl-IgG was found to be 30 times more efficacious than Bchl-Ser: At LD50, only 66,000 Bchl-IgG molecules were bound per bacterium compared to 1,900,000 molecules of Bchl-Ser. The higher efficacy of Bchl-IgG is explained by its exclusive position on the bacterial cell wall. Consequently, photogeneration of oxidative species is confined to the cell wall and its vicinity, a seemingly highly susceptible domain for photodynamic action. In considering the design of cell-specific sensitizers for bacterial and cancer therapies, it would be beneficial to identify the more discretely sensitive subcellular domains as targets.

Bacteriochlorophylls↗

PubMed1997

Proliferation potential and histological features in neurofibromatosis 2-associated and sporadic meningiomas.

The authors compared the histological appearance and proliferation potential of 35 meningiomas in patients with neurofibromatosis 2 (NF2) and 30 sporadic meningiomas in age- and gender-matched patients without NF2. The NF2 meningiomas showed more mitotic figures (p < 0.001) and nuclear pleomorphism (p = 0.003) than the sporadic meningiomas; however, the incidence of meningothelial, fibroblastic, and transitional subtypes occurred equally in both groups. The proliferation potential was significantly higher in the 35 meningiomas removed from 23 patients with NF2 than in the 30 sporadic meningiomas removed in the 30 patients without NF2 (mean MIB-1 labeling indices: 2.5 vs. 1.75, p = 0.0147). The higher proliferation potential of the NF2 meningiomas may reflect differences in molecular biology between sporadic and NF2 meningiomas and may be related to an earlier onset, multiplicity, and more aggressive behavior of NF2 tumors.

Adolescent↗

PubMed1995

Lyme disease in a 74-year-old forest owner with symptoms of dermatomyositis.

We describe a 73-year-old forest owner with widespread erythema, myalgia, and proximal muscle weakness. The clinical signs and the results of electromyography, magnetic resonance imaging, and a muscle biopsy were consistent with dermatomyositis. However, serology was positive for Borrelia burgdorferi. More importantly, B burgdorferi DNA was detected in skin by polymerase chain reaction techniques, and spirochete-like organisms were detected in the muscle by silver staining. Lyme disease with muscle involvement can mimic or trigger dermatomyositis and should be considered in the differential diagnosis of dermatomyositis.

Aged↗

PubMed1995

[Neurotransplantation in Parkinson disease: experimental and clinical results of functional reconstruction of the dopaminergic system].

The first results on functional effects induced by embryonic nigral grafts in the rat model of Parkinson's disease (PD) were reported in the late 70 s. It took another 10 years before the first publications on PD patients demonstrated clinical and neuroradiological signs of improvement after the transplantation of allogeneic embryonic nigral grafts. Technical details as well as clinical results varied considerably in the first clinical studies. In the last years crucial questions have been identified, also because of increasing international cooperation, which represent a challenge jointly to basic and clinical scientists. The clarification of those questions related to scientific and ethical issues will determine which impact the transplantation of embryonic nigral dopamine neurons will have as a potential therapy for PD in clinical medicine.

Animals↗

PubMed1993

Immunohistochemical detection of female sex hormone receptors in meningiomas: correlation with clinical and histological features.

Sixty-one meningiomas from 60 patients were screened for estrogen receptors and progesterone receptors (PgR) with monoclonal antibodies in an immunohistochemical assay. In addition, 43 of the cases were evaluated for tumor size and peritumoral edema, as seen on computed tomographic scans and magnetic resonance images. Sixty-one percent of the tumors contained significant amounts of PgR, whereas no estrogen receptor-positive tumor was observed. Thirteen percent of all tumors were classified as nonbenign variants (atypical and anaplastic meningiomas) and were more frequently found in male patients (P < 0.05). Nonbenign tumors more frequently showed an absence of PgR (P < 0.05), and there was a tendency for PgR-negative tumors to be larger than PgR-positive ones. No correlation was found between PgR status and edema. It is concluded that PgR status in meningiomas is related to tumor differentiation and may be of prognostic value with regard to biological behavior and clinical outcome.

Adolescent↗

PubMed1992

Low incidence of bronchus-associated lymphoid tissue (BALT) in chronically inflamed human lungs.

The relevance of bronchus-associated lymphoid tissue (BALT) in man is still under discussion. Animal experiments indicate that the development of BALT is dependent on microbial stimulation. Therefore, the incidence of BALT was investigated retrospectively in specimens removed during surgical procedures on patients with chronic pulmonary inflammation. All these patients had severe chronic bronchitis and bronchiectasis, but BALT was found in only 8%. In patients with BALT and a malignant tumor, occlusion of a bronchus with poststenotic pneumonia was always present and BALT was observed exclusively in areas peripheral to the occlusion. In man other compartments of the lung must be responsible for the immune function of BALT found in animals.

Adolescent↗

PubMed1992

Ectopic enterobiasis: a case report and review.

Enterobius vermicularis ('pinworm') is rarely found outside the gastro-intestinal tract. We describe a case of extra-intestinal pinworm abscess associated with an inguinal hernia in an adult. A brief review of the literature is given and possible mechanisms of tissue invasion are discussed.

Abscess↗

PubMed1992

Meningeal melanocytoma of the C8 nerve root: case report.

A case of a meningeal melanocytoma involving the C8 nerve root is presented. The clinical symptoms and the radiological investigations resembled a neurinoma of the spinal nerve root. Intraoperatively the tumor was seen to be firmly attached to the dural covering of the dorsal nerve root. By using microsurgical technique, complete removal of the tumor with preservation of the ventral nerve root was accomplished. Histological examination revealed a typical meningeal melanocytoma as described by Limas and Tio in 1972. Ten additional cases of previously reported spinal meningeal melanocytomas are reviewed. The importance of differentiating this benign lesion from meningeal malignant pigmented tumors is stressed.

Adult↗

PubMed1992

[Turcot syndrome illustrated by two clinical cases].

Turcot syndrome denotes the association between either familial polyposis coli (FPC) or sporadic non-familial polyposis coli, and primary neuroepithelial tumors of the central nervous system (CNS). The clinical and morphological intestinal features in both FPC and Turcot syndrome are the same: the histological picture shows typical (tubular) adenomas, often with adenocarcinomatous transformation. As associated CNS tumors astrocytomas, glioblastomas, spongioblastomas, and medulloblastomas are reported. As a modification of ITOH's classification of 1985 we distinguish between four groups: patients with fewer than 100 polyps (group I); patients with fewer than 10 polyps (group II); patients with FPC or sporadic non-familial polyposis (group III); patients with either CNS tumors or FPC with a direct relative with Turcot syndrome and/or FPC (group IV). In patients belonging to the fourth group the diagnosis of Turcot syndrome should not be made. We report on two patients belonging to group II and group IV respectively, and depict the clinical features as well as the heterogenic appearance of Turcot syndrome as outlined in the literature.

Adenomatous Polyposis Coli↗

PubMed1991

Pathological fractures and lytic bone lesion of the femoral neck associated with beta 2-microglobulin amyloid deposition in long-term dialysis patients.

A correlation is demonstrated between chronic hemodialysis using cuprophane membranes (mean duration: 13 years) and pathological fractures (n = 7 in 6 patients) after lytic bone deposits of beta 2-microglobulin amyloid (n = 13 patients). The characteristic symptom complex includes painful impingement syndrome of the shoulder, carpal tunnel syndrome, painful hip and recurrent knee effusions. The first steps of the clinical diagnostic procedure are to demonstrate lytic defects in skeletal radiographs and to verify the presence of beta 2m by biopsy or puncture. Due to reduced regeneration capacity in amyloid bone lesions the resulting surgical therapy should aim at total joint replacement or augmented osteo synthesis. Definitive operative treatment should be aspired even in the absence of manifest fractures, as the natural course of the disease is characterized by progression of the bone destruction and a continuous pain syndrome.

Amyloid↗

PubMed1990

[Autochthonous pulmonary dirofilariasis in Europe].

The chest X-ray of a 39-year-old woman who had an acute onset of fever, cough, dyspnoea and thoracic pain revealed two peripheral round opacities (about 1.5 cm in diameter) in the right lower lobe. Extensive further studies having failed to discover the cause, a diagnostic thoracotomy was performed and the two pleura-adjacent tumours were removed. Histological examination revealed granulomatous encapsulated filariae, species Dirofilaria immitis. This was confirmed by a positive ELISA test with Dirofilaria immitis antigen. As the patient had been on holiday in Corsica three months before onset of symptoms, it is most likely that the pulmonary dirofilariasis was acquired autochthonously in Europe.

Adult↗

PubMed1990

Giant aneurysm causing frontal lobe syndrome.

A 67-year-old patient with a completely thrombosed giant aneurysm of the anterior communicating artery is described. The only neurological findings were a disturbance of stance and gait and slight bilateral grasp reflexes. He had had the features of a frontal lobe psychotic syndrome for more than 12 years. Computed tomography demonstrated a primarily hyperdense calcified suprasellar space-occupying lesion. Magnetic resonance imaging proved valuable in establishing the correct diagnosis, which was confirmed post mortem.

Aged↗

PubMed1990

Imaging of dialysis-related amyloid (AB-amyloid) deposits with 131I-beta 2-microglobulin.

The diagnosis of dialysis-related amyloid (AB-amyloid) has been based usually on clinical and radiological criteria. Following the discovery that beta 2-microglobulin was the major protein of this amyloid, we isolated and radiolabelled uremic plasma beta 2-microglobulin. After intravenous injection, gamma-camera images of selected joint areas were obtained from 42 patients who were on regular hemodialysis therapy. Positive scans involving the shoulder, hip, knee and carpal regions were found in 13 of 14 patients treated for more than 10 years and 10 of 16 patients treated for 5 to 10 years. Patients treated for less time had negative scans. Specificity was indicated by negative scans in non-amyloid inflammatory lesions in control hemodialysis patients. Up to 48-fold tracer enrichment was detected in excised AB-amyloid containing tissue as compared to amyloid-free tissue. These findings suggest that circulating radiolabelled beta 2-microglobulin is taken up by the amyloid deposits. This method may non-invasively detect tissue infiltrates of amyloid. It may also permit prospective evaluation of the efficacy of prophylactic dialysis strategies which are designed to prevent or delay the onset of this complication of long-term dialysis.

Amyloidosis↗

PubMed1990

Cavernous angioma of the cavernous sinus: case report.

An unusual case of cavernous angioma in the cavernous sinus ("cavernous cavernoma") is presented. The acute onset of symptoms simulated Tolosa-Hunt syndrome, and after neuroradiological investigations, the suspected diagnosis was an intracavernous meningioma. Macroscopical intraoperative and histopathological findings demonstrated a cavernous angioma. The lesion was completely removed from the cavernous sinus without additional neurological deficits and with improvement of the symptoms. Three additional cases in the literature are reviewed. The rarity of these lesions and the management problems related to their location in the cavernous sinus are stressed.

Adult↗

PubMed1989

Specific imaging of dialysis-related amyloid deposits using 131I-beta-2-microglobulin.

Dialysis-related amyloidosis (DRA), characterized by its association with beta 2-microglobulin (beta 2m), has become a major concern in long-term hemodialysis patients. Hitherto the diagnosis was based on histological examinations of tissue obtained by biopsy or during surgery. In this preliminary study a new noninvasive diagnostic method was developed using the affinity of beta 2m for its derived fibrils. 3 patients on long-term hemodialysis for 10-16 years with biopsy-proven DRA and 1 patient on chronic hemodialysis for only 6 months were examined after intravenous injection of 131I-labelled beta 2m. Specific local accumulation of radioactivity was noted in the DRA patients after 48 h, persisting for further 96 h and corresponding to clinically or radiologically evident sites of amyloid deposition and to several other hitherto unsuspected sites. Examination of an excised amyloid tumor subsequent to in vivo labelling confirmed a highly specific accumulation of radioactivity in the amyloid tissue but not in control tissue. In the patient on chronic hemodialysis for only 6 months, no specific local accumulation was detected even after 1 week. These findings provide in vivo evidence in man that a specific uptake of circulating amyloid precursor molecules into deposits occurs and that this uptake may be used to radiolabel even small tissue infiltrates of amyloid. This method therefore may not only allow an objective, noninvasive detection of DRA but may also be used to obtain new pathophysiologic insights into amyloid formation in man, as well as permitting the evaluation of preventive therapeutic strategies in prospective studies on new patients.

Amyloidosis↗

PubMed1989

Subcutaneous amyloid-tumor of beta-2-microglobulin origin in a long-term hemodialysis patient.

beta 2-Microglobulin (beta 2M)-derived amyloidosis has become a major concern in long-term hemodialysis patients. Clinical symptomatology is largely restricted to the articular and periarticular sites and in rare cases systemic manifestations have been described. We present a long-term hemodialysis patient, who after 16 years of hemodialysis with regenerated cellulosic membranes not only had a bilateral carpal tunnel syndrome, cystic bone translucencies and humeroscapular periarthritis but also developed two subcutaneous tumors in both gluteal regions, causing discomfort when sitting. Histology, immunohistology and electron microscopy of the tumor from the right side showed that it consisted of beta 2M-derived amyloid with concurrent scattered amyloid infiltration of the overlying skin. This report therefore adds a new clinical manifestation to the symptomatology of this type of amyloid.

Amyloidosis↗

PubMed1989

[Pathologic femoral neck fractures and para-articular beta 2 microglobulin amyloidosis in long-term dialysis patients: an increasingly frequent disease picture].

Beta-2-microglobulin (beta 2-M)-amyloidosis is caused by retention of beta 2-M by dialyzing membranes and by deposition as an atypical amyloid in synovia, bone and tendons. Ten patients under long-term hemodialysis (13 +/- 2.7 years) were treated because of hip pain and cystiform skeletal alterations. First typical joint affections appeared nine years after start of hemodialysis. Five fractures of the hip neck due to large cystiform bone lesions occurred in four subjects. In all cases a total joint replacement was performed.

Amyloidosis↗