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[Neurological manifestations indicative of brucellosis].

Eight patients presented neurological signs secondary to Brucella infection. The clinical presentation was a meningoencephalitis in three cases, a meningoencephalomyelitis in one case, an epiduritis with spinal cord compression in one case, an acute polyradiculoneuritis in two cases and a chronic polyradiculoneuritis in one case. Acoustic nerve was impaired in seven cases. Cerebrospinal fluid (CSF) analysis revealed a lymphocytic meningitis and a high protein concentration in all cases. The agglutination test titers were elevated in the serum and in the CSF of seven patients (> or = 1/80) and two patients respectively. Brucella melitensis culture was disclosed in the blood of one patient and in the CSF of two patients. Three patients were treated by the association cycline and rifampicin whereas a tritherapy including cycline, rifampicin and TMP-SMZ was used in the other cases. Outcome was favorable in seven cases. This study outlines the polymorphism of neurological manifestations due to brucellosis, even in familial cases and this diagnostic must be especially done in Middle East and South Mediterranean countries.

Acute Disease↗

[Effect of cytochalasin D on the structure of mixed synapses and their electrotonic conductivity].

By methods of qualitative and quantitative electronmicroscopy the ultrastructure of mixed synapses of the goldfish Mauthner cell (MC) and their ability to strengthen electrotonic transmission after application of cytochalasin D, a highly specific inhibitor of actin polymerization. On the background of cytochalasin action tetranization of afferent rootlets of acoustic nerve, terminated with mixed synapses on the MC lateral dendrite, failed to induce any long-term potentiation of electronic coupling. On the contrary, a long-term depression of electrotonic transmission was evoked in this case. On the ultrastructureal level such a depression of synaptic conductivity was seen to correlate with a decrease in the number and total length per synaptic apposition of the desmosome-like contacts, known as actin-containing structures, as compared with unstimulated control preparations. In addition, experimental preparations were characterized with unusual quantity of asymmetric desmosome-like contacts, hemidesmosome, whose number during a long-term depression became 4 fold higher than in the control synapses. The data obtained support our recent suggestion on the role of filamentous actin in induction and long-term maintenance of enhanced electrotonic conductivity at mixed synapses.

Animals↗

[Paroxysmic anarthria in multiple sclerosis].

INTRODUCTION: The paroxystic clinical features of multiple sclerosis (MS) include trigeminal neuralgia, itch, transient diplopia, Lhermitte's sign, akinesia, dystonia, Uhthoff's phenomenon and others which are very characteristic, such as paroxystic ataxia and dysarthria. CLINICAL CASE: We present the case of a 30 year old man who consulted for multiple episodes lasting only a few seconds, of complete inability to speak. This symptom recurred several times a day and in many different situations. It was often triggered off by external stimuli such as having to speak in front of several people. The disorder disappeared without treatment seven days after onset. Magnetic resonance using fast spin echo image sequences showed multiple hyperintense lesions in mid right cerebellar peduncle, right pons, left temporal lobe, white substance of both internal capsules, periventricular and semioval centres. Biochemical study of the cerebrospinal fluid showed that there were 9 cells/microliter (mainly lymphocytes), proteins 45 mg/dl and a normal glucose level. The Tibling-Link level was 0.73. Cortical somestesic evoked potentials showed slowed conduction after stimulation of the right median nerve and both peroneal nerves. Acoustic evoked potentials of the brain stem were conducted more slowly by the right acoustic pathway at intraxial level. The patient was diagnosed as having clinically defined MS. CONCLUSIONS: We consider that our patient's symptom was a kind of paroxystic dysarthria which we call paroxystic anarthria. Differential diagnosis of this symptom should be basically with phonatory or dysphasic simple partial seizures.

Adult↗

[The mechanisms of hearing and hearing loss].

The ear is constituted of an apparatus for transmission, the external ear and the middle ear, and of an apparatus for perception, the inner ear or cochlea and the acoustic nerves. A disorder can occur at each of these levels, leading to different types of hearing loss: defective transmission through a disorder of the external canal and/or by disorder of the tympanic-middle ear bone apparatus; endocochlear hearing loss through disorder of the ciliary cells of the Corti ganglion and/or by metabolic disorder or by pressure modification (such as Meniere's disease) of the endolymph compartment of the inner ear; retrocochlear hearing loss through disorders of the 8th nerve; central hearing loss through disorder of the temporal cortex.

Auditory Perception↗

[A rare case of metastatic meningitis with unknown primary focus and atypical symptoms].

We have presented the diagnostic difficulties in the case of woman aged 59 who was admitted to the clinic with the suspicion of neurinoma of acoustic nerve. The patient was admitted to hospital with peripheral facial nerve paresis on the left side together with sudden surdity and peripheral vestibular impairment. Surdity of the other side occurred after two months. In terminal phase of the disease there was aseptic meningitis. Posthumous diagnosis was made on the basis of neuropathological examination of the brain. It was carcinomatous meningitis. But there was no primary focus found during autopsy. It is important to stress that CT and MRI was completely useless in this case. However pathological brain stem response together with lack of stapedial muscle reflex were much ahead of surdity and other central symptoms. We found only one case of carcinomatous meningitis with unknown primary focus in the literature. The course of the disease is very insidious and in every suspicious cases one should be aware of cancer of unknown primary site.

Carcinoma↗

Recruitment in the diagnosis of small PCA tumors.

Acoustic brainstem response (ABR) waveforms were preoperatively analyzed in 86 cases of pontocerebellar angle (PCA) tumors. Absolute (APL) and interpeak latencies (IPL) ipsilateral to the tumor and interaural absolute latency differences of wave V (IAAPLD V) were normal in two patients with small intracanalicular tumors. However, results of latency-intensity studies were abnormal. So, if PCA tumor is suspected, and standard ABRs are normal by usual criteria, the latency-intensity functions should be examined before the test result is reported as negative for an acoustic nerve tumor.

Adult↗

[Comparison of two different recording sites in electrocochleography: promontory and external mastoid position (author's transl)].

One possible evaluation of the functional unit: hair-cell/afferent neurit is the recording of an action-potential (AP) from the acoustic nerve. The authors report their experience in recording the AP from an external position on the mastoid planum and from a transtympanic position on the promontory. The promontory site is prefered because of the higher electrical response amplitude and because of its relatively reduced sensitivity against myogenic potentials. Characteristic findings in normal ears and in some pathological conditions are to be demonstrated.

Action Potentials↗

[Sudden bilateral hearing loss disclosing meningeal carcinomatosis].

We report the case of a patient presenting a sudden bilateral hearing loss. Four years before, a bladder carcinoma was resected and a chemotherapy was started. Gadolinium-enhanced magnetic resonance images revealed enhancement of both acoustic nerves. Cerebrospinal fluid analysis showed malignant cells consistent with the initial bladder cancer. Meningeal metastases from bladder carcinoma are extremely rare. Systemic chemotherapy and its low meningeal diffusion may enhance the incidence of this complication. Bilateral hearing loss is a rare initial manifestation of meningeal carcinomatosis.

Antineoplastic Agents↗

[Electrocochleography as a neurootological tool (author's transl)].

A series of 13 patients where surgery confirmed retrocochlear lesions in the cerebellopontine angle was tested preoperatively by electro-cochleography. The following conclusions can be drawn: 1. Compound action potentials (CAP) of the acoustic nerve could be registered by electro-cochleography in all patients regardless of the fact whether hearing on the side of the lesion could be demonstrated in pure tone audiometry or not. 2. The threshold latency for the 2 kHz sinustone-burst elicited compound action potential was within the normal range if hearing on the side of the lesion could be shown in pure tone audiometry. Threshold latency for 2 kHz CAP was shortened pathologically when hearing on the side of the lesion was absent in pure tone audiometry.

Action Potentials↗

[Investigations of the ototoxicity of dicortinef (ear drops)].

The authors investigated the ototoxic influence of Dicortinef in laboratory animals. Their examinations were performed on 15 guinea pigs (weighing 210-380 g.) after application of this medicine to the fenestra rotunda. The harmful effect of Dicortinef was expressed by the characteristic fall in the microphonic potential (PM) and potential of the acoustic nerve (AP).

Animals↗

[The possibilities of Electric Response Audiometry in Medical Legal Assessment (author's transl)?].

A case of nonorganic hearing loss combined with noise-induced hearing loss and the necessity of differentiating them by Electric Response Audiometry in legal assessment is described. A second example deals with monaural functional hearing loss induced by ill-treatment. Finally is reported on a bilateral neurinoma of the acoustical nerve with an extrem auditory fatique and the impossibility to detect evoked potentials.

Adult↗