Immune evasion by acquisition of complement inhibitors: the mould Aspergillus binds both factor H and C4b binding protein.

Pathogenic fungi represent a major threat particularly to immunocompromised hosts, leading to severe, and often lethal, systemic opportunistic infections. Although the impaired immune status of the host is clearly the most important factor leading to disease, virulence factors of the fungus also play a role. Factor H (FH) and its splice product FHL-1 represent the major fluid phase inhibitors of the alternative pathway of complement, whereas C4b-binding protein (C4bp) is the main fluid phase inhibitor of the classical and lectin pathways. Both proteins can bind to the surface of various human pathogens conveying resistance to complement destruction and thus contribute to their pathogenic potential. We have recently shown that Candida albicans evades complement by binding both Factor H and C4bp. Here we show that moulds such as Aspergillus spp. bind Factor H, the splicing variant FHL-1 and also C4bp. Immunofluorescence and flow cytometry studies show that the binding of Factor H and C4bp to Aspergillus spp. appears to be even stronger than to Candida spp. and that different, albeit possibly nearby, binding moieties mediate this surface attachment.

Mineral crystals in calcified tissues: a comparative study by SAXS.

The shape, the typical orientation, and the average size of mineral crystals in different types of mineralized tissues were investigated by means of small-angle x-ray scattering (SAXS). To rule out eventual artifacts due to sample preparation, four different standard preparation techniques were used and a comparison showed that the SAXS results were identical for all four methods. In mineralized turkey leg tendon, a frequently used model system for bone, the crystals were found to be typically plate-like with a thickness of the order of 2 nm. This stands in contrast to the case of bone (calvaria, femur, and iliac crest) from mouse, rat, and dog, where mainly needle-like crystals were found. The thickness of these crystals ranged from 3 to 4 nm but was remarkably constant for different bones of a given animal. The preferred orientation of the needle-like crystals was along the main axis of the femur and within the surface of the calvaria (for mouse, rat, and dog). The mineral plates in turkey leg tendon were located inside the hole zone and oriented along the fibril axis. Finally, no periodic arrangement of the crystals inside the hole zone of the collagen could be found.

Single photon emission computed tomography in AIDS dementia complex.

Single photon emission computed tomography (SPECT) studies were performed in AIDS dementia complex using IMP in 12 patients (and HM-PAO in four of these same patients). In all patients, SPECT revealed either multiple or focal uptake defects, the latter corresponding with focal signs or symptoms in all but one case. Computerized tomography showed a diffuse cerebral atrophy in eight of 12 patients, magnetic resonance imaging exhibited changes like atrophy and/or leukoencephalopathy in two of five cases. Our data indicate that both disturbance of cerebral amine metabolism and alteration of local perfusion share in the pathogenesis of AIDS dementia complex. SPECT is an important aid in the diagnosis of AIDS dementia complex and contributes to the understanding of the pathophysiological mechanisms of this disorder.

Cerebrovascular lesions and livedo reticularis (Sneddon's syndrome)--a progressive cerebrovascular disorder?

Four cases are described in which livedo reticularis was associated with repeated cerebrovascular accidents, which eventually resulted in severe disability in two cases. Patients with severe disability had a history of many years, whereas two patients with little or moderate residual disability had a follow-up of 3 years each. CT scan revealed multifocal cerebral infarctions and cortical atrophy in all cases. Repeated cerebral angiograms, done in three cases, showed no signs of a vascular disease. There were no parameters that pointed to active immunological or inflammatory disorder. Neither clinical evidence of heart or large vessel disease was found. Observations suggest that a so-far unknown progressive cerebral vessel disease associated with livedo is the cause of a steady increase in multiple small cerebral infarctions. Because of the progressive character of the disease the search for effective therapy is needed.

Diesel soot particles catalyze the production of oxy-radicals.

The formation of a strong oxidant similar to the OH. radical is catalyzed by diesel soot particles in the presence of cysteine and hydrogen peroxide or in the presence of light. The oxidant(s) formed causes fragmentation of methylthioketobutyric acid measurable as ethylene release. Furthermore, the model carotenoid crocin is bleached and thiobarbituric-acid-reactive material (malondialdehyde) is produced from linolenic acid. All reactions are inhibited by scavengers (propyl gallate, alpha-tocopherol, diazobicyclooctane) and by catalase. The reactions observed suggest that the toxicity and mutagenicity of diesel soot particles is at least in part due to the formation of reactive oxygen species.

[The CT-controlled treatment possibilities in intervertebral disk prolapses]. / CT-kontrollierte Behandlungsmöglichkeiten bei Bandscheibenvorfällen.

A CT-controlled method for the treatment of lumbar and cervical disc prolapse is described. Compared with fluoroscopically controlled percutaneous lumbar discectomy, percutaneous treatment of the L5/S1 disc by a dorsal approach is possible even in the presence of high iliac crests, as is described in this paper. In the cervical region the risk of iatrogenic damage is reduced. In a small group of 42 patients, an attempt has been made to remove disc material which is intraforaminal, intraspinal, subligamentous or sequestered. Amongst 79 patients with lumbar and 15 patients with cervical disc prolapse treatment was successful in 85% (after 17 months of observation) and 93% (after 12 months of observation). These figures refer to the early results from a new method. The success of the method will have to be assessed after a larger number of patients has been treated and there has been a longer period of observation.

[Sonographic determination of the position of the carotid bifurcation as a diagnostic aid in cerebral catheter angiography]. / Sonographische Lagebestimmung der Karotisgabel als diagnostische Hilfe bei zerebralen Katheter-angiographien.

A simple sonographic method is described for demonstrating the position of the carotid bifurcation in the sagittal plane. As a result, it is possible to demonstrate the bifurcation by angiography without overlay, thereby improving the diagnosis of vascular abnormalities. Since non-invasive sonography of the carotid arteries should be carried out before cerebral angiography in any case, the present procedure does not involve any additional effort.

[Digital subtraction discography]. / Digitale Subtraktionsdiskographie (DSD).

Conventional cervical discography was carried out in 25 patients during the period of one year. At the same time, we employed the well known principle of digital subtraction. The results of DSD have been compared with conventional discography. In every case more informative images were obtained despite the use of lower amounts of contrast. The distribution pattern of the reduced amounts of contrast in the disc provides valuable information. In the shoulder region, great improvement in picture quality is possible. For these reasons, the use of digital subtraction for discography is justified.

Doppler and duplex sonography of the cervical arteries and correlations with other examinations. A field study in a population over forty years.

Of the population of a small Tyrolean village, 185 (56%) of the 329 inhabitants over 40 years were investigated by means of Doppler and duplex sonography, electroencephalography (EEG), electrocardiography (ECG), and neurological examination. Four subjects (2%) previously had a transitory ischemic attack (TIA) or stroke in the carotid territory. Sonographically detectable abnormalities in one or more extracranial arteries were present in 42 (23%) persons. Of the 14 subjects with more than slight abnormalities in the common or internal carotid artery two were symptomatic. Two additional cases with TIA or stroke did not show relevant lesions on sonographic examination. The presence of narrowing in the extracranial artery was not related to risk factors (hypertension, smoking, obesity) or abnormalities on ECG and EEG. This study shows 1) that the clinical relevance of ultrasound screening of the carotid arteries in an average population is 15%; 2) that significantly more patients with TIAs or strokes are found in the group with more severe sonographic findings (p = 0.001) than in the group with normal ultrasound results.

Steroid-induced complete remission in a case of primary cerebral non-Hodgkin's lymphoma.

A case of a primary non-Hodgkin's lymphoma of the CNS is reported in which a complete and stable disappearance of an enhancing mass lesion on the CT scan after treatment with dexamethasone was followed by the occurrence of a high-grade malignant lymphoma in the opposite hemisphere 18 months later. The long-lasting and stable remission suggests a direct oncolytic effect of corticosteroids on lymphoma cells. Furthermore, this case illustrates the usefulness of repeated CT examinations in patients with CNS lymphoma and steroid treatment.

[Regression of motor symptoms after intervertebral disk displacement-induced spinal nerve root lesion. Clinical study]. / Rückbildung motorischer Ausfälle nach diskushernienbedingter Nervenwurzelläsion. Klinische Studie.

Ever since the causal relationship between backache, radicular pain and intravertebral disc herniation was established [25], there have been different opinions about the degree of recovery of motor lesions of the nerve root caused by disc herniation. Of 123 patients with a severe motor deficit of the L5 nerve root, 95 patients were available for a follow up examination 4 to 8 years after the operation. The statistical evaluation showed that the degree of recovery of the root lesion was mainly dependent on the age of the patient and the time interval until operation. Even a prior herniation of the disc without much compression of the nerve root can cause chronic damage to the nerve through traction at the trilamellar nerve root fixation. So even in the case of only a small disc hernia with a corresponding nerve root lesion, we would recommend immediate operative therapy.

[Neuroradiologic treatment possibilities of intervertebral disk displacement]. / Neuroradiologische Behandlungsmöglichkeiten bei Bandscheibenvorfällen.

A CT assisted method for automated percutaneous lumbar discectomy (APLD) is described. With this technique and introduction of a "pull and push" method as well extruded and sequestrated herniated lumbar discs as cervical herniated discs can be treated. The CT assisted discectomy was performed in 70 patients. The success rate was 86% in the lumbar region and 93% for cervical herniated discs. We believe that this percutaneous technique will increase the importance of interventional neuroradiology for this common disease.