PubMed Health⌕ Search

Biomedical subjects

C Kessler

Publications and source records attributed to C Kessler.

At least 181 records · Page 10Linked to original sources
PubMed1986

Detection of carotid thrombi with indium-111 platelet scintigraphy.

In order to prove that platelet scintigraphy (PSC) is able to detect carotid thrombi formations, we performed PSC in 15 patients directly before or immediately after a percutaneous carotid angiography. PSC was successful in demonstrating iatrogenic fresh carotid thrombi in 13 out of 15 cases. Out of 53 patients with cerebrovascular disease and carotid stenosis a pathologic platelet accumulation was seen in 39 carotid arteries, 31 on the symptomatic side; more often in slight- and middle-sized stenoses than in high degree stenoses. We assume that in these cases PSC detected carotid thrombi which caused arterio-arterial emboli.

Angiography↗
PubMed1986

123I-N-isopropyl-amphetamine single photon emission computed tomography as a brain imaging technique in dementia.

Because of its binding to specific cerebral amine receptor sites 123I-N-isopropyl-amphetamine (IMP) tracer activity can be used as a measure for the regional cerebral blood flow (rCBF) in the human brain. In 21 psychiatric in-patients an IMP perfusion study was performed using a rotating gamma camera system. The findings at single photon emission computed tomography (SPECT) were compared with different clinical parameters including conventional transmission computed tomography. In SPECT, two different patterns of decrease in IMP uptake could be identified. In patients with a history of cerebrovascular disease SPECT showed asymmetrical, multifocal microcirculatory defects without preference for either hemisphere. In patients with suggested Alzheimer type dementia the perfusion deficits involved the gray and white matter of the parieto-occipital lobes in a bilaterally symmetrical mode with variable extension. Thus, by using IMP-SPECT, it was possible to define the underlying pathologic condition in dementia.

Adult↗
PubMed1985

Two new restriction endonucleases DraII and DraIII from Deinococcus radiophilus.

In addition to recently characterized DraI (1), two new Type II restriction endonucleases, DraII and DraIII, with novel site-specificities were isolated and purified from Deinococcus radiophilus ATCC 27603. DraII and DraIII recognize the hepta- and nonanucleotide sequences (sequence in text) The cleavage sites within both strands are indicated by arrows. The recognition sequences were established by mapping of the cleavage sites on pBR322 (DraII) and fd109 RF DNA (DraIII). The sequence specifities were confirmed by computer-assisted restriction analyses of the generated fragment patterns of the sequenced DNA's of the bacteriophages lambda, phi X174 RF, M13mp8 RF and fd109 RF, the viruses Adeno2 and SV40, and the plasmids pBR322 and pBR328. The cleavage positions within the recognition sequences were determined by sequencing experiments.

Bacteriophage lambda↗
PubMed1985

Recognition sequences of restriction endonucleases and methylases--a review.

The properties and sources of all known endonucleases and methylases acting site-specifically on DNA are listed. The enzymes are crossindexed (Table I), classified according to homologies within their recognition sequences (Table II), and characterized within Table II by the cleavage and methylation positions, the number of recognition sites on the DNA of the bacteriophages lambda, phi X174 and M13mp7, the viruses Ad2 and SV40, the plasmids pBR322 and pBR328 and the microorganisms from which they originate. Other tabulated properties of the restriction endonucleases include relaxed specificities (Table III), the structure of the restriction fragment ends (Table IV), and the sensitivity to different kinds of DNA methylation (Table V). Table VI classifies the methylases according to the nature of the methylated base(s) within their recognition sequences. This table also comprises those restriction endonucleases, which are known to be inhibited by the modified nucleotides. Furthermore, this review includes a restriction map of bacteriophage lambda DNA based on sequence data. Table VII lists the exact nucleotide positions of the cleavage sites, the length of the generated fragments ordered according to size, and the effects of the Escherichia coli dam- and dcmI-coded methylases M X Eco dam and M X Eco dcmI on the particular recognition sites.

Base Sequence↗
PubMed1985

[Cerebellar atrophy in epileptic patients: computer tomography study].

We examined the CT-scans of 310 patients with epilepsy and found a cerebellar atrophy (CA) in 56 cases. 8 of them concerned the cerebellar hemispheres and 48 the vermis. The CA was predominantly observed in patients treated with phenytoin, who had experienced one or more phenytoin intoxications. The combination of phenytoin and carbamazepine resulted in a high risk of acquiring a CA. The CA did not depend on the age of the patients or on the presence of major generalised tonic-clonic seizures.

Adult↗
PubMed1985

[Detection of intracardiac thromboses with 111-In platelet scintigraphy].

A scintigraphy with Indium-111 labelled platelets was performed in 11 patients with suspected brain embolism. In six patients, an intracardial thrombus was found: four in the region of the left ventricle and two in the left atrial. The echocardiography revealed no pathological findings in 2 of the 6 patients with positive scans. Angiography in both patients indicated occlusions of the carotis interna siphon, which frequently accompany embolisms. Subsequent angiographies four weeks later showed that the occlusions had reopened. The thrombus investigation, performed with the aid of Indium-111 platelet scintigraphy, appears to be a valuable extension of the present diagnostic potential in the determination of questionable cardial embolisms.

Adult↗
PubMed1984

Three new restriction endonucleases MaeI, MaeII and MaeIII from Methanococcus aeolicus.

Three type II restriction endonucleases, MaeI, MaeII and MaeIII, with novel site specificities have been isolated and purified from the archaebacterium Methanococcus aeolicus PL-15/H. The recognition sequences of these enzymes are (formula: see text) with the sites of cleavage as indicated by the arrows. The sequences were confirmed by restriction and computer analyses on sequenced DNA's of plasmid pBR322, bacteriophages lambda and phi X174 and virus SV40.

Base Sequence↗
PubMed1984

Hallervorden-Spatz syndrome restricted to the pallidal nuclei.

The case history is presented of a man who died at the age of 38 years and had been suffering from severe torsion dystonia and a hypokinetic-rigid motor disturbance since the age of 10. The pathological findings were isolated pallidal degeneration with demyelination and moderate neuronal loss, iron pigment accumulation and spheroid bodies in both pallidal nuclei. In addition the zona reticularis of the substantia nigra was hypoplastic and not affected. The red nucleus, the dentate nucleus and the zona reticularis of the substantia nigra showed iron depigmentation. The rare condition of non-familial Hallervorden-Spatz syndrome, without involvement of the zona reticularis and the cerebral cortex, was considered to be the diagnosis.

Adult↗
PubMed1984

Dual isotope scintigraphy in stroke patients.

Platelet scintigraphy is a useful technique to detect atherosclerotic lesions of the neck vessels in stroke patients. The habitual one isotope technique causes false positive and false negative results due to circulating platelet-bound activity. To eliminate these confusing results we performed a dual isotope technique on 20 stroke patients. The new method consists of simultaneous injections of 111-Indium labelled blood platelets and 99mTc labelled red cells, and achieves a calculation of the ratio 111-In/99mTc. Thus the subtraction of the red cell blood flow image can render a pure thrombus formation visible. The habitual visually evaluated one isotope scintigraphy showed positive scans in 11 out of 20 patients, whereas under dual isotope scintigraphy 3 patients showed no 111-Indium excess after subtraction of the red cell image; they can thus be qualified as false positive. In the case of another patient with a visually negative image a thrombus formation could be observed after the subtraction procedure. It seems, that the dual isotope technique in platelet scintigraphy is a valuable refinement on the way to verifiable results.

Blood Platelets↗
PubMed1984

Dual isotope carotid scintigraphy in patients with amaurosis fugax attacks.

A new dual isotope scintigraphic (DISC) examination of the carotid arteries consisting of simultaneous injections of 111In-labeled platelets and 99mTc-labeled red cells was performed on eight male patients suffering from amaurosis fugax attacks. In concordance with the angiographically proven high percentage of significant extracranial carotid disease in patients with amaurosis fugax, six of the eight patients examined had an increased platelet accumulation in the carotid artery clinically affected. In one patient with normal angiography and one amaurosis fugax attack the platelet scintigraphy even revealed a pathological platelet accumulation in the ipsilateral carotid artery. These findings confirm the hypothesis that most amaurosis fugax attacks are due to arterio-arterial emboli originating from atherosclerotic plaques of the carotid bifurcation.

Aged↗
PubMed1984

CAT scan and immunohistochemical findings in a case of cerebral thromboangiitis obliterans (Buerger's disease).

Immunohistochemical examinations were carried out in a case of thromboangiitis obliterans. A 26-year-old man developed 4 brain infarctions which could be demonstrated by CAT scan. He suffered from a left-sided hemiparesis, major epileptic seizures, and an ischemic optic neuritis. Immunologic studies supported a diagnosis of cerebral thromboangiitis obliterans (CTAO). The serum anti-elastin titer as well as IgE were considerably increased and a biopsy of the temporal artery showed immunohistochemical signs of an acute inflammatory vessel disease. After the diagnosis of CTAO had been made, the patient was treated with azathioprine and dexamethasone. In cases of young stroke patients, a temporal biopsy is important in confirming the diagnosis.

Adult↗
PubMed1984

New aspects of thromboangiitis obliterans (von Winiwarter-Buerger's disease).

The existence of thromboangiitis obliterans as a clinical entity has been a matter of debate for many years. In contrast to other immunovasculitides there is no organ involvement while peripheral vessels are affected. Heavy smokers under 40 years of age have a high predisposition for the disease. The cerebral form shows relapsing brain infarctions which can be visualized in CCT while panarteriography remains negative. Apart from unspecific inflammatory signs in blood and CSF there are distinctive laboratory findings proving the autoimmunological character of von Winiwarter-Buerger's disease. In the serum anti-elastin antibodies, IgE and anticollagen antibody activity are detectable. In 3 patients the authors detected specific immunohistochemical findings in a biopsy specimen of the temporal artery. In addition to platelet-inhibiting substances corticoids in acute and azathioprine in chronic treatment becomes necessary.

Antigen-Antibody Complex↗
PubMed1983

The clinical use of platelet scintigraphy with 111-In-oxine.

Platelet scintigraphy was performed on 62 patients with cerebral ischaemia. Pathological scintigraphic images were obtained in 29 of the 62 patients. In 79.3% of these 29 patients the scan was abnormal in the vessel clinically affected. Platelet scintigraphy was abnormal in 21 of 34 patients with normal angiogram or only slight atherosclerosis. In patients undergoing antiplatelet therapy, platelet scintigraphy was less often positive than in untreated patients. It is suggested that platelet scintigraphy could be an appropriate technique for detecting small mural thrombi of the carotid artery, which are the source of arterio-arterial emboli, and for controlling the efficiency of antiplatelet therapy.

Adult↗