[Maine de Biran (1766-1824), founder of the Société médicale de Bergerac]

Maine de Biran is essentially well known as a great philosopher but he was a prefect too - a high civil servant who represents the government in the French 'departments" - and a politician. In 1806, he founded, for physicians and chemists of his district the "Société médicale de Bergerac", one of the earliest created in France. The Society hold two meetings every year. At that time, it was considered that diseases were essentially caused by climatic ans topographic factors. The vaccination against smallpox, discovered by Jenner in 1796, was often debated. Sixty years before Charcot, a hysterical crisis of a young girl was perfectly described by a member of the Society. There was no professional secret and the patients' names were given. Recent publications were analysed; it was the case for the percussion of the thorax recently described by an Austrian physician. The Society took end in 1810, by lack of members and communications.

Magnetoneurographic 3D localization of conduction blocks in patients with unilateral S1 root compression

OBJECTIVES

Tibial nerve somatosensory evoked magnetic fields (tSEFs) over the lower back reflect the propagation of compound action currents along fibers of plexus, nerve roots and cauda equina. One clinical perspective for this 'magnetoneurography' is the non-invasive 3D localization of focal slowing or blocks of conduction. Here, first tSEF mappings in 3 consecutive patients with acute unilateral S1 nerve root compression are reported.

METHODS

Right and left tibial nerves were electrostimulated in alternation; tSEF responses were recorded using a multichannel SQUID-detector; additionally, spinal and cortical SEP, F-wave and H-reflex studies were performed.

RESULTS

In all patients an intraindividual side-to-side comparison of spinal tSEF mappings was obtained: using a dipolar source model compound action currents could be visualized propagating along plexus, nerve roots and cauda equina on the non-affected side whereas on the affected side normally-propagating dipolar field patterns could be recorded only distal to the spinal transforaminal root entrance; this reflects focal slowing or block of conduction in nerve root fibers as indicated by the SEP, F-wave and H-reflex study results.

CONCLUSIONS

With a registration time of 15 min a 3D localization of proximal slowing or block of conduction was successfully performed in patients suffering from acute nerve root lesions.

Etiology and risk factors of 180 cases of native valve endocarditis. Report from a 5-year national prospective survey in Slovak Republic

Risk factors, etiology, and outcome of 180 cases of infective endocarditis (IE) in the Slovak Republic for 5 years were prospectively studied in a national survey. According to the Duke Endocarditis Service Criteria (1994), 169 cases were considered definitive and 21 possible/probable. The aortic valve was infected in 46.7%, mitral in 47.2%, and tricuspidal/pulmonary in 6.1% of cases. The majority of endocarditis cases was caused by Staphylococcus aureus and coagulase-negative staphylococci (CNS) (33.3%); only 12.2% were due to viridans streptococci; 11.7% were due to Enterococcus faecalis; 6.1% due to Haemophilus spp.; 10.1% due to other organisms; and 26.7% were culture negative. Single positive cultures of CNS were not considered clinically significant. More than 25% of 180 patients were older than 60 years. Rheumatic fever was a risk factor in 35.5%, dental surgery in 20.5%, prior cardiosurgery in 7.8%, and neoplasia in 6.7%. All patients were treated with antimicrobials (average length of therapy was 29.5 days) and 33.3% of patients also had surgery (valvular prosthesis replacement). Forty (22.2%) died, and 140 (77.8%) survived at day 60 after the diagnosis of endocarditis was made. All 40 deaths were attributable to infection. Univariate analysis comparing deaths and survivors did not show significant differences in most of the recorded risk factors between both groups, except age > 60 (40.0% versus 21.4%, p < 0.05), staphylococcal etiology (55.0% versus 27.1%, p < 0.04), and antibiotic therapy < 21 days (without surgery) (65.0% versus 3.6%, p < 0.01). These risk factors were significantly more frequently associated with deaths. Viridans streptococcal IE and surgical therapy in addition to antibiotics were associated with lower mortality in comparison to staphylococcal endocarditis (p < 0.045) or to cases treated with antibiotics only (p < 0.05). In comparison to other nationally based surveys in Europe (Greece, Croatia, France), the percentage of culture-negative endocarditis and spectrum of pathogens differed significantly.

Cigarette smoking as a determinant of high-grade carotid artery stenosis in Hispanic, black, and white patients with stroke or transient ischemic attack

BACKGROUND AND PURPOSE

We sought to investigate the association of cigarette smoking with high-grade carotid artery stenosis in Hispanic, black, and white patients with cerebral ischemia in two independent samples.

METHODS

Prospectively collected data from the Northern Manhattan Stroke Study (NOMASS) (n=431) and the Berlin Cerebral Ischemia Databank (BCID) (n=483) were used separately for a cross-sectional study estimating the association between cigarette smoking and high-grade carotid stenosis (defined as a luminal narrowing of > or =60%, diagnosed by duplex and/or Doppler ultrasound). In both studies, cerebral ischemia patients with normal sonographic findings or nonstenosing plaques of their carotid arteries served as a comparison group. Multivariate logistic regression models were used for statistical tests to determine the association between smoking and the dependent variable for high-grade carotid stenosis. Age, sex, hypertension, diabetes, hypercholesterolemia, and race/ethnicity were considered potential confounders. Further analyses of the NOMASS data estimated the effect of the amount of cigarette use and the impact of race/ethnicity.

RESULTS

High-grade carotid stenoses were found in 14% of the NOMASS and in 21% of the Berlin patients. In Berlin the entire sample was white, whereas in New York only 19% of the cohort were white. In both samples, smoking was independently associated with severe carotid stenosis (NOMASS: odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1 to 2.0; BCID: OR, 3.9; 95% CI, 2.4 to 6.4). Patients smoking 20 pack-years or more showed a significant association (OR, 2.0; 95% CI, 1.1 to 3.9), whereas no significant effect was found for lower amounts of cigarette use. In NOMASS, white smokers displayed a significant (OR, 3.2; 95% CI, 1.1 to 8.9) association with high-grade carotid stenosis, the association for black smokers was less strong, and no association was found among Hispanics.

CONCLUSIONS

Smoking is an independent determinant of severe carotid artery stenosis in patients with focal cerebral ischemia. The association differs by race/ethnicity, with the greatest effect observed among whites.

[Septo-optic dysplasia (de Morsier syndrome)]

Septo-optic dysplasia (or de Morsier syndrome) is a congenital disorder characterised by anomalies in cerebral midline structures, optic nerve hypoplasia, and hormonal deficiencies. Diagnosis should be made early, due to the possibility of treating the hormonal disturbances. We describe here a case with decreased visual acuity, one-sided hemianopia, nystagmus und agenesis of the septum pellucidum and discuss the heterogeneous appearance of this syndrome. There are two theories regarding its pathogenesis. The first postulates simultaneous damage to both cerebral structures and optic nerve development around the 6th week of gestation, while the other favours secondary degeneration of optic nerve fibres due to a cerebral lesion.

[Effect of cardiac embolism sources on origin of territorial cerebral infarcts]

BACKGROUND AND PURPOSE

To test the association of cardiac sources of embolism with territorial type brain infarcts.

METHODS

From a prospective cerebral ischemia data base the 106 consecutive patients with territorial type cerebral infarcts on computerized tomography were analyzed. The 85 consecutive patients with lacunar lesions served as a comparison group. The association of cardiac sources of embolism with territorial types infarcts was assessed using univariate Chi Square tests and logistic regression models. Cardiac sources of embolism were defined as:atrial fibrillation, left cardiac thrombi, valvular vegetations, wall motion and valvular abnormalities, left atrial enlargement, open foramen ovale, septal aneurysm, mitral valve prolaps, and aortic arch atherothrombosis (all findings--except for atrial fibrillation--assessed by echocardiography).

RESULTS

Atrial fibrillation was significantly associated with territorial type infarcts (odds ratio 2.2, 95% confidence interval 1.01-4.8). This effect was independent of additional cardiac diseases, other cardiac abnormalities, carotid artery stenosis, and patient age. Most likely due to the small sample size, left cardiac thrombi only showed a non-significant trend towards an association with territorial infarcts (odds ratio 3.0, 95% confidence interval 0.7-12.3). The rate of all other cardiac findings did not differ significantly between the comparison groups.

CONCLUSION

Atrial fibrillation and cardiac thrombi showed an association with territorial type infarcts. Other so-called cardiac sources of embolism--except for mechanical valves and bacterial endocarditis which were not represented in our sample--revealed no clinically relevant association with embolic brain infarct pattern.

Intravenous immunoglobulin treatment of neurological autoimmune diseases

Intravenous immunoglobulin (IVIg) has been widely used in neurological diseases during the last decade. The current indications of IVIg in neurological diseases are reviewed and discussed on the basis of the available experimental data and clinical trials. Compared to other immunomodulating treatments used in neurological diseases, IVIg has only few side effects with a small risk of transmission of infectious agents. Good clinical evidence for the effectiveness is available for Guillain-Barré-Syndrome, chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy. In conditions like myasthenia gravis and myositis favourable effects of IVIg were reported, but future studies have to be awaited. For all other neurological conditions where IVIg has been administered, there is currently no support for the use of IVIg other than in controlled trials. In conclusion, IVIg is a promising immunomodulary therapy that has been shown to be effective in some neurological autoimmune diseases. Routine use in neurological practice should be restricted to diseases for which a positive effect has been proven in controlled trials. For all other conditions no definite recommendations can presently be made.

Cerebellar atrophy with basilar artery occlusion

Small and large vessel occlusive disease leading to chronic cerebral ischemia and brain atrophy is a concept originating in the last century. The modern notion of acute brain infarct, however, appears to have eclipsed the idea of chronic hypoperfusion as an important factor in ischemic cerebral damage. We present a patient history featuring recurrent episodes of acute posterior circulation infratentorial ischemia in addition to a progressive cerebellar syndrome over a course of several years. Laboratory work-up including cerebral angiography, repeated CT and MR scanning revealed basilar artery occlusion, a pontine infarct and a subsequently developing cerebellar atrophy without signs of cerebellar infarction. Findings indicating causes of cerebellar atrophy other than ischemia could not be elicited. We offer the hypothesis that basilar artery occlusion, inducing subsequent chronic ischemia, is the most likely cause of the cerebellar atrophy observed in our case.

Somatotopic source arrangement of 600 Hz oscillatory magnetic fields at the human primary somatosensory hand cortex

Based on low-noise superconducting quantum interference devices (SQUIDs) magnetoencephalography allows the non-invasive detection of low-amplitude high-frequency brain responses evoked about 20 ms after electric hand nerve stimulation. The main spectral energy of these brief oscillatory bursts (near 600 Hz) is in the range typical for rapidly repeated action potentials. Here, the magnetic fields of median and ulnar nerve evoked 600 Hz bursts are shown to exhibit a somatotopic arrangement at the primary somatosensory hand cortex closely resembling that of the concomitant postsynaptic primary cortical response (¿N20m'). Two possible burst generators are discussed: (1) repetitive spike volleys conducted along the terminal segments of somatotopically arranged thalamocortical axons, and (2) early intracortical spike activity in nerve-specific subterritories of the 3b hand area.

Side effects of high-dose intravenous immunoglobulins

Intravenous immunoglobulins (IVIgs) are used increasingly as therapy for neuroimmunologic and other autoimmune diseases. With broader use, the number of reported side effects also is growing. Here we review the literature on adverse reactions reported after administration of i.v.Igs. Despite a few recent reports about a high frequency of complications of IVIgs, by and large they can be considered as safe. Mild and self-limited side effects may occur, but severe complications are rare and often associated with other risk factors for these complications. A careful screening for preexisting illnesses and monitoring of some laboratory parameters can minimize the risks of IVIg therapy.

Immunoglobulins for intravenous use inhibit TNF alpha cytotoxicity in vitro

Intravenous immunoglobulins (IVIg) have been used as an immunomodulatory therapy in a variety of diseases. Several mechanisms of action have been proposed, one of which is interference with the cytokine network. We have investigated the effect of IVIg on the cytotoxicity of human TNF alpha. IVIg was capable of protecting L929 fibroblasts from TNF alpha induced cell death. This effect was not species specific and was mediated by both the Fc and the Fab portion of immunoglobulins. Since the effect was also seen when IVIg was added after the removal of TNF alpha from the culture medium, it seems to be independent of the interaction of TNF alpha with its receptor. We conclude that IVIg either act on some point of the TNF alpha signalling pathway or influence the cell cycle unspecifically. The cytoprotective effect of IVIg potentially could contribute to the beneficial effect described for various diseases.

Dendrite cell-T cell mixtures, isolated from the skin and mucosae of macaques, support the replication of SIV

Previous studies have shown that HIV-1 exploits dendritic cells (DCs) to replicate and spread among CD4+ T cells. The DCs within mucosal surfaces may be especially important, but these are more difficult to access. To study more extensively the properties of DCs and other leukocytes from skin and different mucosae, DCs were isolated from uninfected macaques and their sensitivity assessed to infection with SIV in vitro. Dendritic cells and T cells readily emigrated from organ cultures of macaque skin, as described previously for humans. In addition, characteristic cells emigrated from explants of mucosae, both nasopharyngeal (adenoid and tonsil) and genital (vagina and cervix). The macaque DCs reacted with the monoclonals that are used to study human DCs, such as MAbs to CD40, CD86, CD83, and the p55 protein. When SIV was added to the DC-T cell mixtures from these different organs, extensive replication was observed in all but the cervical leukocytes. SIV replication occurred without the use mitogens, and with virus that had been grown in a cell line in the absence of mitogens and IL-2. Most of the newly synthesized viral protein is observed in syncytia. Therefore, mixtures of DCs and T cells isolated from mucosal surfaces served as a naturally permissive environment for SIV replication.

Mapping of tibial nerve evoked magnetic fields over the lower spine

Using a low-noise 49-channel dc-SQUID system spinal somatosensory evoked fields (SEF) were recorded which were generated by compound action currents evoked upon posterior tibial nerve stimulation. The SEF mapping showed the action current propagation along the sciatic nerve, lumbosacral plexus and cauda equina in parallel to simultaneously recorded electrical potentials (SEP). For a reliable intraindividual side-to-side comparison of spinal SEFs the right and left tibial nerves were stimulated in alternating order; this procedure minimizes artifactual inter-nerve SEF map differences due to eventual patient-to-sensor displacements which might occur in serial measurements. These large-area lumbar SEF mappings open up several clinical perspectives for magnetoneurography, in particular with respect to the 3D-localization of proximal conduction blocks.

Hämodilutionsbehandlung des ischämischen Insultes

Hämorheologische und experimentelle Befunde weisen darauf hin, daß eine Verbesserung der Perfusion normaler und ischämischer Hirnareale durch die Hämodilution möglich ist. Die Verbesserung ist in Arealen mit ungestörter Autoregulation im wesentlichen durch eine Verringerung des Hämatokrit und damit der Sauerstofftransportkapazität des Blutes bedingt. Bei gestörter Autoregulation spielen Viskositätsparameter eine zusätzliche Rolle. Berechnungen aufgrund von Untersuchungen an Gesunden legen die Annahme nahe, daß ein Hämatokrit von etwa 0,42 für die Sauerstofftransportrate zum Gehirn optimal ist. Dieser optimale Hämatokrit verschiebt sich nach experimentellen Daten in ischämischen Arealen möglicherweise zu höheren Werten. Ein Unterschreiten des optimalen Hämatokrit durch Hämodilution ist nur tolerabel, wenn Kompensationsmechanismen, wie Erhöhung des Herzminutenvolumens und ein stabiles Blutdruckverhalten, gewährleistet sind. Entsprechend diesen Prämissen haben Untersuchungen mit isovolämischer Hämodilution, die nicht zur Erhöhung des Herzminutenvolumens führt, keine positiven, z.T. sogar negative Ergebnisse erbracht. Hypervolämische Hämodilution birgt die Gefahr einer erhöhten Sterblichkeit infolge Hirnödem, Herz- oder Nierenversagen. Lediglich eine Untersuchung mit moderater hyper-volämischer Hämodilution hat ein eindeutig positives Ergebnis ausgewiesen. Studien mit einer den individuellen Gegebenheiten des Patienten angepaßten hypervolämischen Hämodilution zeigten bei nicht signifikant höherer Sterblichkeit eine Tendenz zu geringerem klinischen Defizit bei den Überlebenden. Prospektive Untersuchungen zur Klärung der Indikation und gegebenenfalls optimalen Modalität der Hämodilution sind nötig.

Die Therapie des akuten ischämischen Insultes

Der ischämische Insult ist ähnlich dem Herzinfarkt ein akuter Notfall, der unmittelbarer Diagnostik, Behandlung und Überwachung bedarf. Hierzu sind adäquate personelle, apparative und logistische Voraussetzungen zu schaffen. Überwacht werden sollten neben dem neurologischen Verlauf Blutdruck, EKG, Atmung, Temperatur und möglichst auch O2-Sättigung. Der meist situativ erhöhte Blutdruck bei Aufnahme darf (außer bei Komplikationen wie Angina pectoris) nicht sofort, sondern erst nach 15-20 Minuten und nicht um mehr als 20% gesenkt werden. Interventionsgrenzwerte müssen individuell bestimmt werden. Hypotone Werte sollten durch Volumengabe und in Ausnahmefällen durch Vasopressiva bekämpft werden. Eine Hämodilution (Verminderung der Sauerstofftransportkapazität) ist nicht indiziert, wohl aber eine moderate Volumensubstitution. Der Wert der Fibrinolyse ist z. Zt. nicht gesichert. Antiaggreganzien verbessern wahrscheinlich die Prognose eines Insultes, gleiches gilt für niedrigdosiertes Heparin. Der Einsatz PTT-wirksamer Heparindosen ist nicht gesichert und sollte auf Patienten mit hohem Frührezidiv-oder Verschlechterungsrisiko beschränkt bleiben. Zur Prophylaxe des Hirnödems sind 20-30° Hochlagerung des Oberkörpers, optimale Atmung und Normothermie wesentlich. Hyperosmolare Lösungen sind nur bei eingetretener intrakranieller Druckerhöhung (nicht prophylaktisch) anzuwenden. Bei ausgedehnten, raumfordernden Infarkten ist eine Dekompressionsoperation möglich. Physikalische Therapie in der Frühphase verringert das Risiko von Sekundärschäden und verbessert die Chancen einer funktionellen und emotionellen Restitution.

[Association of hypertension and diabetes mellitus with microangiopathic cerebral infarct patterns]

OBJECTIVE

To test the hypothesis of a positive association of hypertension and diabetes mellitus with cerebral small-vessel disease infarct patterns.

METHODS

Using a prospective stroke database, the 152 patients with computertomographic signs of small-vessel disease (lacunes and/or leucoaraiosis)--including as a subgroup of 85 cases with multiple lacunes and/or leucoaraiosis-were compared with 106 patients featuring pial artery infarcts. Statistical analyses of the rates of hypertension and diabetes included univariate tests (odds ratios) and a logistic regression model comprising the additional variables hypercholesterolemia, cigarette smoking, carotid stenosis, atrial fibrillation, and left cardiac thrombus.

RESULTS

Multivariate testing revealed a significant association of hypertension and diabetes with multiple lacunar infarcts and/or leucoaraiosis (hypertension: odds ratio 2.0; 95% confidence interval 1.04-3.7; diabetes: odds ratio 1.9; 95% confidence interval 1.01-3.8), whereas for the total group of patients with small-vessel disease lesions no such effect was found. Among the other tested variables, only atrial fibrillation/left cardiac thrombus showed a significant negative association (odds ratio 0.5; 95% confidence interval 0.2-0.9) with lacunes/leucoaraiosis.

CONCLUSION

Independent of other risk factors and other possible causes of stroke, both hypertension and diabetes appear to be strong determinants of multiple lacunar infarcts and/or leucoaraiosis.

MR evaluation of age-related increase of brain iron in young adult and older normal males

The purposes of this study were to extend the investigation of age-related increases in brain iron to a younger age group, replicate previously published results, and further evaluate the validity of a novel noninvasive magnetic resonance (MR) method for measuring tissue iron (ferritin) levels with specificity. The method consists of measuring the dependence of tissue transverse relaxation rates (R2) on the field strength of MR instruments. Two MR instruments operating at 1.5 and 0.5 T were used to measure the field-dependent R2 increase (FDRI) in the frontal white matter, caudate, putamen, and globus pallidus. A group of 13 normal adult males (ages 21-77), with seven subjects below and six above age 35, was examined. As expected from postmortem and prior FDRI data, robust and significant age-related increases in FDRI were observed in the caudate, putamen, and globus pallidus, with the globus pallidus FDRI increasing sharply in the second decade and reaching a plateau after age 30. In addition, we replicated previous reports showing very high correlations between FDRI and published brain iron levels for the four regions examined. The data replicate and extend previous FDRI observations on brain aging and are consistent with postmortem data on age-related increases in brain iron. These results are relevant to the investigation of age-related neurodegenerative diseases in which iron may catalyze toxic free radical reactions.

Cutaneous dendritic cells promote replication of immunodeficiency viruses

The cutaneous or mucosal DC-T cell environments seem extremely supportive of immunodeficiency virus replication. Apart from very early after SIV infection, similar virus producing cells have been difficult to detect in the lymphoid tissues where DCs and T cells are also known to interact. Large amounts of virus can be visualized in the germinal centers of the lymph nodes, much of which represents immune complexed virus that is trapped on the follicular dendritic cell surface. However, whether these virus-carrying cells actually make virus or even virus proteins requires further investigation. We believe that once an individual is systemically infected, free virus and/or virus-infected cells will seed peripheral tissues and when encountering similar DC-T cell environments as described in the oral mucosae, can set up sites of chronic virus replication. For instance, a virus-carrying T cell that migrates to the periphery would, on entering this milieu, interact with the mature DCs and activate virus production. This likely occurs at similar sites around the body, such as the mucosal associated lymphoid tissue of the gut, and is probably independent of the route of infection.

[Diagnostic advantage by transthoracic and transesophageal echocardiography in acute ischemic infarct. A contribution to indications for transesophageal echocardiography]

The yield of TTE and TEE in identifying cardiac sources of embolism in patients with TIA or stroke was calculated from data from the Berlin Stroke Data Bank. High risk sources of embolism were detected by TTE in 4.2% with and in 1.6% of patients without evidence of cardiac disease from case history, clinical symptomatology, and ECG respectively. TEE yielded high risk sources of embolism in 10.6% of patients with and in 4.2% of patients without evidence of cardiac disease from case history, clinical symptomatology, ECG, and TTE respectively. Pathological findings were 12 atrial thrombi, 4 ventricular thrombi, and 1 atrial myxoma. 12 out of 14 atrial thrombi were only detected by TEE and not by TTE. There was a significant association of high risk cardiac sources of embolism with pial artery infarct pattern in CCT compared with lacunes. The yield of TEE in detecting high risk sources was not significantly associated with CCT infarct pattern probably due to the small numbers of investigations.

Percutaneous techniques for endoluminal carotid interventions

PURPOSE

To describe the evolving techniques for stent implantation in the proximal and cervical carotid arteries.

METHODS AND RESULTS

Percutaneous access to proximal and cervical carotid lesions is either via direct puncture of the common carotid artery or through the more familiar retrograde common femoral (RCF) artery approach. Both techniques and their variations are described in detail, along with their benefits, disadvantages, and possible complications. Dual lesions at the arch and higher up the neck can be treated either from the RCF route or, if the cervical lesion requires endarterectomy, with open exposure at the bifurcation and stenting of the proximal lesion.

CONCLUSIONS

While the RCF route is more familiar to the majority of interventionists and provides adequate access in most situations, traversing the arch and negotiating acute angles at the ostia of the great vessels may render this method infeasible. The direct puncture technique is a useful alternative; however, it requires more expertise to prevent potentially disastrous access-site complications. One further caveat must be stated: regardless of the access approach selected, the opportunity for serious, debilitating-and lethal-complications is always present in cerebrovascular interventions. At this earliest phase in our experience with carotid stenting, cautious investigative methodologies must prevail.

Intravascular ultrasound assessment in carotid interventions

PURPOSE

To demonstrate the clinical value of intravascular ultrasound (IVUS) imaging in monitoring stent deployment in the cervical carotid arteries.

METHODS AND RESULTS

Two-dimensional (2D) and three-dimensional (3D) IVUS imaging has been used routinely in more than 100 patients following carotid stenting and the completion angiogram to detect evidence of inaccurate stent deployment. Axial 2D views were used to measure diameters and cross-sectional areas and provide the basis for 3D reconstruction. These composited images produced single-frame views of entire vascular segments, with definition of vessel wall morphology, stent placement, and angioplasty-induced defects. This information was used in the decision to apply further treatment to the area in order to maximize luminal diameter and/or correct defects.

CONCLUSIONS

IVUS imaging is an important component of carotid artery stent procedures. It more accurately visualizes stent placement and vessel wall morphology than arteriography, information critical to the intraprocedural assessment process.

[Potential embolism sources in transesophageal echocardiography--prognostic value in patients with cerebral ischemia]

To determine whether potential sources of embolism such as atrial septal aneurysm (ASA), patent foramen ovale (PFO), mitral valve prolapse and atherosclerotic aortic debris can influence the outcome of patients after first cerebral ischemic event (CIE), 214 patients (124 stroke, 21 RIND, 69 TIA) were examined by transesophageal echocardiography (TEE) up to 3 weeks after CIE and followed up for 12 months. For risk estimation, the patients were subdivided into group I = without and group II = with potential sources of embolism. We additionally took into account cardiovascular diseases and atherosclerotic risk factors (group la + IIa without, Ib + IIb with). Recurrence occurred in 14 out of 214 patients (6.5%). Univariate analysis demonstrated that the presence of ASA, PFO and aortic debris as well as cardiovascular diseases and atherosclerotic risk factors was associated with a twofold to threefold higher incidence of recurrent events. While potential sources of embolism alone had no influence on the recurrence rate (group I:8/111 = 7.2% versus group II: 6/103 = 5.8%, n.s.), this was significantly different in relation to cardiovascular diseases and atherosclerotic risk factors (groups Ia + IIa: 0/66 = 0%, groups Ib + IIb: 14/148 = 9.8%, p < 0.01). Our results show that potential sources of embolism do not appear to influence the recurrence rate in cardiac healthy subjects. In patients with cardiovascular diseases, however, potential sources of embolism are associated with a higher risk of recurrence, and should therefore be imaged by TEE.

Prevalence of antibodies against simian immunodeficiency virus (SIV) and simian T-lymphotropic virus (STLV) in a colony of non-human primates in Kenya, East Africa

Sera (165 samples in 1988 and 66, follow-up samples in 1989) were collected from olive baboons, African green monkeys, Syke's monkeys and grey mangabeys kept in a semi-free, breeding colony at the Institute of Primate Research (IPR) in Nairobi, Kenya. The levels of antibodies to simian T-lymphotropic virus (STLV) or simian immunodeficiency virus (SIV), and the reactivity patterns of positive sera to various lentivirus subgroup antigens, were then determined. The results of tests using enzyme-immunoassay kits were confirmed by western blots. The prevalence of antibodies which reacted with the Kenyan SIVagm(KEN) isolate was 28% in the African green monkeys tested and 34% in the Syke's monkeys. STLV seroprevalence was 25% in the African greens and 20% in the Syke's. No antibodies to either SIV or STLV were detected in the olive baboons or grey mangabeys. More SIV-positive samples were detected in western blots when SIVagm(KEN) was used as antigen than when SIVagm(CAR014), a geographically distinct isolate from the Central African Republic, was used. However, SIVagm(KEN)-positive sera were more reactive against SIVagm(CAR014) than SIVsmm and SIVmac subgroup antigens, indicating that the two isolates from the African green monkey, CAR014 and KEN, remain antigenetically close even though they were recovered in two geographically distinct regions. To date, no clinical disease has been linked with SIV and STLV infection in the African green or Syke's monkeys in the colony. However, the relatively high prevalence of anti-SIV and anti-STLV antibodies in these monkeys offers an opportunity for prospective studies on the transmission and natural history of both viruses in a single colony.