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Biomedical subjects

A Probst

Publications and source records attributed to A Probst.

At least 55 records · Page 3Linked to original sources

[Differential anterior interosseous nerve syndrome diagnosis].

The differential diagnosis of the rupture of flexor pollicis longus tendon and profundus tendon to index finger to the interosseus anterior nerve syndrome can be difficult and can lead to misinterpretation of the clinical impression. Two cases are reported to demonstrate this problem. In the first case a spontaneous rupture of flexor pollicis longus was found, when first an interosseus anterior nerve syndrome was suspected. In a second case surgical exploration of flexor pollicis longus tendon and profundus tendon to index finger was done on the assumption of a rupture, that revealed intact tendons. In a second operation neurolysis of the interosseus anterior nerve was carried out with full recovery of flexion of the thumb and index finger.

Adult↗

Confocal microscopic localization of anti-myelin-associated glycoprotein autoantibodies in a patient with peripheral neuropathy initially lacking a detectable IgM gammopathy.

We report here on a patient with anti-myelin-associated glycoprotein (MAG) neuropathy in whom examination of a sural nerve biopsy by multichannel confocal microscopy showed a partly overlapping distribution of MAG and IgM deposits in myelinated fibers. Our data demonstrate that MAG in Schmidt-Lanterman incisures and paranodal loops, as well as some additional HNK-1-positive components of the basal lamina, are the major targets of the anti-MAG monoclonal IgM autoantibodies in this neuropathy in vivo. Perforation of the basal lamina can allow the penetration and binding of anti-MAG IgM inside myelinated fibers. Our results support and extend the notion that the production of monoclonal anti-MAG IgM may be antigenically driven by MAG molecules and that this process may occur in the immunologically privileged environment of the nerve prior to the appearance of a genuine gammopathy in serum.

Autoantibodies↗

Apolipoprotein E allele frequencies in argyrophilic grain disease.

Apolipoprotein E (ApoE) genotypes were analyzed in 35 subjects with argyrophilic grain diseases (AgD). Neuropathologically, all cases were characterized by abundant argyrophilic grains in the hippocampus and in the entorhinal or parahippocampal cortex. We found an ApoE epsilon4 allele frequency of 0.007 in AgD patients, which is significantly different from the epsilon4 allele frequencies reported in age-matched Alzheimer's disease (AD) patients (0.24), but not from age-matched controls (0.09). We conclude that the ApoE epsilon4 allele does not constitute a risk factor for the development of AgD. Our results further suggest that AgD is a progressive disorder differentiated from AD by morphological and genetic criteria.

Aged↗

Prognostic significance of MIB-1, p53, and bcl-2 immunoreactivity in meningiomas.

Sixty biopsy specimens of meningiomas, including 37 benign, 10 atypical, and 13 malignant meningiomas, were examined immunohistochemically using the monoclonal antibodies MIB-1 (a cell proliferation marker), p53, and bcl-2 (two apoptosis-associated markers). Benign meningiomas were subdivided into two groups: group 1, 29 tumors without recurrence; and group 2, eight tumors with recurrence after complete surgical resection. The mean MIB-1 labeling index (LI) values+/-SD were 1.3+/-3.2% for the benign, 9.3+/-6.9% for the atypical, and 15.0+/-16.9% for the anaplastic meningiomas. The mean MIB-1 LI+/-SD in group 1 tumors (n = 29) was 1.06+/-1.15%, and in group 2 tumors (n = 8), 2.3+/-4.76% (P = .028). p53 protein expression was found in 10.8% of the benign (10.34% of group 1 and 12.5% of group 2), 50% of the atypical, and 77% of the anaplastic meningiomas. bcl-2 protein expression was observed in 21.6% of the benign, 20% of the atypical, and 46.1% of the anaplastic meningiomas. Among the benign meningiomas, group 2 tumors expressed significantly more often bcl-2 protein (62.5%) than group 1 neoplasms (10.3%). Our results indicate that (1) in meningiomas, a good correlation exists between histological grading, MIB-1 and p53 protein expression, and (2) in benign meningiomas, the presence of bcl-2 protein expression together with high MIB-1 LI are associated with unfavorable prognosis of the disease.

Adult↗

Argyrophilic grains of Braak: occurrence in dendrites of neurons containing hyperphosphorylated tau protein.

Braak's argyrophilic grains (ArGs) are spindle-shaped neuropil structures originally found in patients afflicted with adult onset dementia. We recently observed that tau protein is hyperphosphorylated in most nerve cells in areas rich in ArGs, suggesting that these grains may be a morphological expression of tau protein pathology in local neurons. The aim of this study was therefore to determine in three cases with ArGs whether grains are associated with individual neurons containing hyperphosphorylated tau. A combination of Gallyas silver staining and AT8 immunocytochemistry was used. AT8 is a monoclonal antibody that recognizes tau in a phosphorylation-dependent manner. Up to 80% of pyramidal cells of sector CA1 showed diffuse AT8 staining of their cell bodies and dendrites. Most grains were freely scattered throughout the neuropil. However, some were clearly located in side-branches of apical dendrites of AT8 immunoreactive pyramidal neurons. Dendritic branches often formed bush-like ramifications containing clusters of ArGs. Other dendrites consisted of a single stump containing one or two large grains at their tips. Spheroidal enlargements of dendritic branches, with a size corresponding to ArGs, were also found in Golgi Cox preparations of cases with ArGs but not in Alzheimer's disease cases or in controls. Our results show that some ArGs are formed within dendrites of neurons whose most obvious pathology is a diffuse hyperphosphorylation of the tau protein. Furthermore, morphology of dendrites containing grains suggests that a process of progressive shrinkage of dendrites is taking place in neurons bearing ArGs.

Aged↗

[Anatomic and radiographic examination of the shoulder joint of the cheetah (Acinonyx jubatus)].

Anatomical structures of shoulder joints of five adult cheetahs were examined by dissection, corrosion casts and radiography. The bones, capsules and auxiliary synovial devices were described, as well as ligaments and adjacent muscles. The cheetah shoulder has many similarities with the shoulder joint of the domestic cat, but also considerable differences. Proper osteological features were the large supraglenoid tubercle, the caudally directed coracoid process and the extension of the articular surface of the scapula to the lateral area of the supraglenoid tubercle. On the proximal end of the humerus the width of the head of humerus, the facet of infraspinatus muscle as a shallow cavity with the insertion of the infraspinatus muscle around it and two raised roughnesses on the proximal end of the tricipital line for the insertions of the lateral glenohumeral ligament and the teres minor muscle were noticeable. The insertion of the joint capsule was mainly on the glenoid labrum, only in part of the articular surface on the lateral area of the supraglenoid tubercle laterally on the scapula. The joint capsule formed a supra- and infraspinatus recess laterally, an intertubercular tendon sheet for the biceps brachii muscle cranially, and a bipartited subscapular recess medially. An extracapsular transverse ligament passing the intertubercular groove, a laterally capsular strengthening--called lateral glenohumeral ligament--and an intracapsular medial glenohumeral ligament could be found. The latter one was joined to the capsule by a mesoligament, dividing the subscapular recess into two pouches.

Acinonyx↗

[Anatomic characteristics pf the elbow joint of the cheetah (Acinonyx jubatus)].

Anatomical structures of elbow joints of six cheetahs were examined by dissection, corrosion casts and radiography. As a result, it was observed that the distal end of humerus is divided into the trochlea humeri for articulation with the ulna and the capitulum humeri for articulation with the radius. As the trochlea humeri is posed oblique and looks like a disc-shaped cone sector, flexion. Flexion of elbow joint is always combined with adduction of the distal parts of the limb, and, respectively, extension with abduction. The cylindrical but also in sagittal direction convex capitulum humeri enables the head of the radius all movements on a spheric sector. Furthermore, advantageous preconditions for rotation in the proximal radioulnar joint are the mighty medical coronoid process, the displacement of the radial tuberosity to the caudal surface of the radius and the insertion of the biceps brachii muscle exclusively on this elevation of the radius. Limiting factors are the insertions of collateral ligaments at the antebrachial skeleton. The lateral collateral ligament inserts only on the radius, the medial collateral ligament mainly on the ulna. The radial anular ligament directly connects the two coronoid processes of the ulna and moreover is intracapsular. The joint capsule is common for both the cubital and the proximal radioulnar joint and five pouches could be described. These were between the lateral epicondyle of humerus and the olecranon, underneath the tendon of origin of the extensor carpi ulnaris muscle, cranially in the bend of the elbow joint, between the head of the radius and the tendon of origin of supinator muscle and the lateral part of radial anular ligament, just as between the medial epicondyle of humerus and the tendons of origin of flexor muscles of the forearm.

Acinonyx↗

Histological markers in nasal mucosa of patients with Alzheimer's disease.

Neuropathological changes such as dystrophic neurites and the presence of abnormal tau protein in the olfactory system, including primary sensory cells and nerve fibres have previously been demonstrated in nasal mucosa tissue of patients with Alzheimer's disease (AD). These changes were detected in autopsy-derived material from histopathologically confirmed AD cases as well as in biopsy tissue from clinical severely ill AD patients. To investigate the potential usefulness for the early diagnosis of AD, we obtained biopsy tissue from olfactory mucosa from 5 clinically mild to moderate AD patients and stained for the presence of tau or beta-amyloid by immunocytochemistry using a panel of specific antibodies. No positive staining was found in any of the cases. For comparison, post-mortem olfactory tissue from AD patients with severe neuropathological changes (widespread neurofibrillary tangles and amyloid in the brain) was investigated. In these severe cases, tau immunoreactivity was found in fine nerve fibres in the lamina propria and in a few olfactory epithelial cells. These results are consistent with other reports showing that cytoskeletal changes and tau pathology in the olfactory epithelium are not primary (or specific) features of AD and may occur predominantly in late stages of the disease.

Aged↗

Primary progressive aphasia with glial cytoplasmic inclusions.

We report a 80-year-old woman who suffered from primary progressive aphasia for 3 years. Cranial CT and MRI studies showed moderate cerebral atrophy, more marked in the left frontal and temporal lobes, and SPECT brain scans revealed marked hypometabolism in the left frontal and temporal lobes. Neuropathologic examination of a temporal lobe biopsy demonstrated Gallyas-positive intracytoplasmic inclusions looking like fibrillary tangles and of Gallyas-positive cell processes, probably from glial cells. Glial intracytoplasmic inclusions were immunolabelled with antibodies to ubiquitin and with phosphorylion-dependent antitau antibodies, indicating the presence of hyperphosphorylated tau in the inclusions. There was only mild pathology of cortical neurons consisting in rare perikarya diffusely stained with antitau antibodies. There were no senile plaques, neurofibrillary tangles, 'achromatic' neurons, ballooned cells, Pick or Lewy bodies, nor microvacuoles or spongiform changes of the neuropil. The glial intracytoplasmic inclusions found in this case were similar to those found in multiple system atrophy, and differ from the cortical changes hitherto reported in primary progressive aphasia.

Aged↗

Two amyloid precursor protein transgenic mouse models with Alzheimer disease-like pathology.

Mutations in the amyloid precursor protein (APP) gene cause early-onset familial Alzheimer disease (AD) by affecting the formation of the amyloid beta (A beta) peptide, the major constituent of AD plaques. We expressed human APP751 containing these mutations in the brains of transgenic mice. Two transgenic mouse lines develop pathological features reminiscent of AD. The degree of pathology depends on expression levels and specific mutations. A 2-fold overexpression of human APP with the Swedish double mutation at positions 670/671 combined with the V717I mutation causes A beta deposition in neocortex and hippocampus of 18-month-old transgenic mice. The deposits are mostly of the diffuse type; however, some congophilic plaques can be detected. In mice with 7-fold overexpression of human APP harboring the Swedish mutation alone, typical plaques appear at 6 months, which increase with age and are Congo Red-positive at first detection. These congophilic plaques are accompanied by neuritic changes and dystrophic cholinergic fibers. Furthermore, inflammatory processes indicated by a massive glial reaction are apparent. Most notably, plaques are immunoreactive for hyperphosphorylated tau, reminiscent of early tau pathology. The immunoreactivity is exclusively found in congophilic senile plaques of both lines. In the higher expressing line, elevated tau phosphorylation can be demonstrated biochemically in 6-month-old animals and increases with age. These mice resemble major features of AD pathology and suggest a central role of A beta in the pathogenesis of the disease.

Alzheimer Disease↗

Biodistribution of 111In-labelled SCN-bz-DTPA-BC-2 MAb following loco-regional injection into glioblastomas.

We analyzed the biodistribution of the 111In-labelled murine anti-tenascin-C MAb BC-2 after intralesional injection in 15 glioblastoma patients. The activated ligand DTPA was conjugated via the isothiocyanato-benzyl group onto BC-2. Conjugates were labelled with 111In, displaying immunoreactivity greater than 90% and labelling efficiency of 99 +/- 1%. In contrast to i.v. injections, excellent tumor uptake was obtained by direct intralesional injection of conjugates that showed only slow systemic release. In serum, conjugates were found to be intact; in urine, only low-molecular-weight decay products were detected. In 8 patients, outflow from the site of injection into systemic circulation was low; daily activity in the serum and urine was found to be below 2% of the total injected radioactivity; most of the injected activity was retained within the tumor, resulting in effective half-lives of 58 +/- 5 hr. In contrast, higher outflow up to 10% of regionally injected 111In-DTPA-BC-2 MAb into systemic circulation resulted in considerable shortening of the effective half-lives to 20 to 40 hr in 7 patients. This outflow was found to correlate with tumor size and blood/brain barrier disruption. In one patient, HPLC analysis of tumor cyst fluid 3 and 6 days after intralesional injection revealed conjugates to be intact and allowed the estimate of about 70% of the total injected 111In-DTPA-BC-2 to be confined to tumor tissue. We conclude that different outflow patterns can be observed following locoregional injection of 111In-DTPA-BC-2, leading to considerable variations in the effective half-lives of isotopes within the tumor, requiring adjustment of the radiation dose in therapeutic trials.

Aged↗

Pharmacological characterisation of human cerebral cortex somatostatin SRIF1 and SRIF2 receptors.

Radioligand binding studies were performed in membranes of human cerebral cortex using [125I]Tyr3-octreotide in the presence of 5 mM MgCl2, [125I]SRIF-14 ([125I]Tyr11-SRIF-14) and [125I]CGP 23996 ([125I]c[Asu- Lys-Asn-Phe-Phe-Trp-Lys-Thr-Tyr-Thr-Ser]) both in the presence of 120 mM NaCl, to characterise the nature of the somatostatin (SRIF) receptors. The pharmacological profile of human brain SRIF recognition sites was compared with that of recombinant human SRIF1 (sst2-sst3-sst5) or SRIF2 receptors (sst1-sst4) and with that of native rat sst1, sst2, and sst4 receptors. [125I]Tyr3-octreotide labelled binding sites in human cerebral cortex: Bmax = 238 +/- 36 fmol/mg protein and pKd = 9.73 +/- 0.08. The pharmacological profile of [125I]Tyr3-octreotide labelled sites correlated very significantly with that of recombinant human sst2 receptors (r = 0.98) and much less with those of recombinant human sst3 (r = 0.65) or sst5 receptors (r = 0.72). The correlation between [125I]Tyr3-octreotide binding to native sst2 receptors in human and rat cerebral cortex was also highly significant (r = 0.97). [125I]SRIF-14 and [125I]CGP 23996 binding (performed in the presence of 120 mM NaCl) in the human cerebral cortex identified very similar populations of sites Bmax = 44 +/- 7 and 36 +/- 5 fmol/mg protein and pKd = 9.44 +/- 0.08 and 9.48 +/- 0.10, respectively. The pharmacological profiles of the sites labelled with [125I]SRIF-14 and [125I]CGP 23996 correlated highly significantly with those of recombinant human sst1 (r = 0.97-0.99) or sst4 receptors (r = 0.91-0.94). Similarly, the correlations between [125I]SRIF-14 or [125I]CGP 23996 binding in human cortex and [125I]SRIF-14 binding to native sst1 sites in rat cerebral cortex were also highly significant (r = 0.97 and 0.94, respectively). Finally, the pharmacological profile of native rat lung sst4 sites determined with [125I]LTT-SRIF-28 ([Leu8,D-Trp22, 125I-Tyr25]SRIF-28) correlated with [125I]SRIF-14 and [125I]CGP 23996 binding in human cortex; r = 0.91 and 0.87, respectively. The present data show that in human cerebral cortex, [125I]Tyr3-octreotide labels SRIF1 receptor sites which are best characterised as of the sst2 type, whereas [125I]SRIF-14 and [125I]CGP 23996 (both in the presence of 120 mM NaCl), label sites which fit almost equally well with sst1 or sst4 receptors and therefore are best described as of the SRIF2 type. Under the conditions used, there was no evidence that either of these ligands would label sst3 or sst5 receptors in human cerebral cortex.

Animals↗

Autoradiographic analysis of somatostatin SRIF1 and SRIF2 receptors in the human brain and pituitary.

The distribution of somatostatin (SRIF) receptor sites was studied by in vitro receptor autoradiography in the human brain and pituitary using the SRIF1 (sst2) receptor selective [125I]Tyr3-octreotide, the non-subtype selective [125I]LTT-SRIF-28 ([Leu8,D-Trp22, 125I-Tyr25]SRIF-28) and the SRIF2-receptor selective [125I]CGP 23996 (c[Asu- Lys-Asn-Phe-Phe-Trp-Lys-Thr-Tyr-Thr-Ser]) in buffer containing 120 mM Na+. SRIF receptor autoradiography was compared with mRNA expression of somatostatin receptors sst1-5 as studied by in situ hybridisation in human brain. High levels of [125I]LTT-SRIF-28 and [125I]Tyr3-octreotide recognition sites were found in the deep layers of cerebral cortex and molecular layer of cerebellum of the human brain. The hypothalamus, choroid plexus, most areas of the brainstem and dentate nucleus were associated with low levels of binding. In contrast to [125I]LTT-SRIF-28 and [125I]Tyr3-octreotide, no difference was observed for [125I]CGP 23996 labelling in the various layers of cerebral cortex. The choroid plexus, substantia nigra and molecular layer of the cerebellum presented high densities of [125I]CGP 23996 binding sites whereas no binding was observed in the hypothalamus and locus coeruleus using this radioligand. Both lobes of the human pituitary displayed low levels of [125I]LTT-SRIF-28 and [125I]Tyr3-octreotide binding. By contrast, the anterior lobe of the pituitary displayed very high levels of [125I]CGP 23996 labelled sites whereas intermediate levels were found in the posterior lobe. There was a partial overlap between sst2 receptor mRNA and [125I]Tyr3-octreotide binding, although the distribution of the binding sites was much wider than that of receptor mRNA. The same observation was made for sst1 and/or sst4 receptor mRNA and [125I]CGP 23996 labelled sites. The present data show that SRIF1 and SRIF2 receptors are present in the human brain with different distributions, especially in the cerebral cortex and the pituitary. The very similar distribution of sites labelled with [125I]LTT-SRIF-28 and [125I]Tyr3-octreotide suggests (i) that sst2 receptors are predominant within the SRIF1 family in the human brain and (ii) that [125I]LTT-SRIF-28 under the conditions used in the present study, does not significnatly label SRIF2 sites.

Autoradiography↗

Argyrophilic grain disease: widespread hyperphosphorylation of tau protein in limbic neurons.

Argyrophilic grains (ArG) and coiled bodies of argyrophilic grain disease (AgD) and the neurofibrillary lesions of Alzheimer's disease (AD) share similar antigenic determinants, among them hyperphosphorylated microtubule-associated protein tau. Nothing is known about the mechanisms underlying tau hyperphosphorylation in AgD, the hyperphosphorylated sites or the intracellular distribution of abnormally phosphorylated tau. We have analysed brain tissue sections from 41 subjects with AgD with a panel of phosphorylation-dependent (AT270, AT8, Tau-1, AT180, 12E8, PHF-1 and AT100) and phosphorylation-independent anti-tau antibodies (N-tau 5, 304, 189 and 134). All antibodies labelled ArG, coiled bodies and neurofibrillary lesions, with the exception of antibody 12E8, which stained a subset of neurofibrillary tangles, but no ArG or coiled bodies. Most pyramidal neurons in areas rich in ArG showed diffuse granular tau labelling in cell bodies and dendrites. Only very few tau-positive cells also contained neurofibrillary tangles. Phosphorylation-dependent anti-tau antibodies also stained a felt-like network of Gallyas-negative filiform neurites in layer CA1 of the hippocampus and in layer pre-B of the transentorhinal cortex. These results demonstrate a widespread hyperphosphorylation of tau protein in the somatodendritic domain of neurons in AgD, in addition to silver grains in the neuropil. Unlike in AD, tau hyperphosphorylation in the somatodendritic domain in AgD does not appear to be followed by neurofibrillary tangle formation, even in the presence of widespread ArG in the neuropil. Furthermore, our data suggest that no strict correlation exists between the presence or density of ArG in the limbic area and the occurrence of dementia.

Aged↗

Argyrophilic grain disease: distribution of grains in patients with and without dementia.

In a previous study we reported on a late onset dementia which occurred in only half of the patients with argyrophilic grain disease (AgD) investigated. To find a correlation between the distribution of argyrophilic grains (ArG) and the occurrence of a late onset dementia, we examined the limbic area in 35 subjects who had ArG as the main neuropathological finding. A retrospective clinical analysis was performed by collecting information from hospital charts supplemented by standardized interviews based on DSM IV criteria for dementia. Sections from the rostral and caudal hippocampal regions, including the entorhinal/transentorhinal and parahippocampal cortex on both sides, were strained by the Gallays method. Nineteen subjects were diagnosed as demented according to these criteria; 16 were considered to have been cognitively normal. High numbers of ArG were observed in the anterior part of the CA1 subfield in all cases. However, the posterior half of CA1 was involved significantly more often and more severely in demented than in non-demented individuals (P < 0.01). Moreover, the distribution of ArG in the entorhinal/transentorhinal and parahippocampal cortex was more widespread in the group of demented patients (P < 0.05). These results show that the intellectual status of patients with AgD was related to the extension of ArG in the limbic area. We suggest that AgD is a progressive neurodegenerative disorder with early subclincial lesions in the anterior part of the hippocampal formation. To provide a more accurate clinicopathological correlation, the rostrocaudal extension of ArG in the limbic area should be evaluated in AgD cases.

Aged↗

Development and characterization of antibodies against the N terminus of the human dopamine D4 receptor.

The human dopamine D4 receptor (hD4R), which has been implicated in human diseases such as schizophrenia and in a personality trait called "novelty seeking," has not yet been characterized at the protein level. Following epitope scanning of the hD4R, we have produced a highly specific monoclonal antibody named DFR1 raised against an amino-terminal peptide in a predicted extracellular region of the receptor. DFR1 decorated recombinant hD4Rs on the surface of intact Chinese hamster ovary (CHO) cells by flow cytometry and fluorescence microscopy and also recognized recombinant hD4.2, hD4.4, and hD4.7 receptor isoforms by western blot analysis. When expressed stably in CHO cells, all three hD4R isoforms contained N-linked glycosylation and showed apparent molecular masses of 48, 55, and 67 kDa for hD4.2, hD4.4, and hD4.7, respectively. DFR1 immunoreactivity representing hD4R protein or dopamine D4 receptor-like antigens was observed in crude membrane extracts of postmortem human brain tissue by immunoblotting. The DFR1 antibody provides a new immunological tool with the potential to further our understanding of the human dopamine D4 receptor protein.

Amino Acid Sequence↗

[Ambulatory surgery in the hospital: decision between national health insurance responsibility and personal job security].

The aim of outpatient surgery is to reduce costs in the health service. However, the number of surgeons working in a surgical department is dependent upon the numbers of occupied beds. This creates an existential conflict in which, by reducing the occupancy of beds in order to take on more outpatient cases, surgeons are putting their own jobs on the line. Possible solutions are here discussed.

Ambulatory Surgical Procedures↗

[Frontal lobe dementia: a case report].

Frontal lobe dementia (FDL) is a disorder that has only been described in recent years. It is mainly characterized by language disturbances and personality changes. We describe the problems and the possible therapeutic approaches to FLD, using a single case which has been well documented for several years.

Aged↗