Search for Dark Matter Axions with CAST-CAPP.

The CAST-CAPP axion haloscope, operating at CERN inside the CAST dipole magnet, has searched for axions in the 19.74 µeV to 22.47 µeV mass range. The detection concept follows the Sikivie haloscope principle, where Dark Matter axions convert into photons within a resonator immersed in a magnetic field. The CAST-CAPP resonator is an array of four individual rectangular cavities inserted in a strong dipole magnet, phase-matched to maximize the detection sensitivity. Here we report on the data acquired for 4124 h from 2019 to 2021. Each cavity is equipped with a fast frequency tuning mechanism of 10 MHz/ min between 4.774 GHz and 5.434 GHz. In the present work, we exclude axion-photon couplings for virialized galactic axions down to gaγγ = 8 × 10-14 GeV-1 at the 90% confidence level. The here implemented phase-matching technique also allows for future large-scale upgrades.

Some etiologic factors of speech comprehension disturbances.

Disturbances of speech comprehension were analyzed in a prospective study of 97 children, aged from 23 to 77 months. Pregnancy, birth and early psychomotor development were normal for all the children and no focus of neurological deficit was found. A tonal audiometer did not detect any auditory disturbances, and psychological testing with non-verbal tests showed normal mental functioning for the age. In this group of selected subjects, family and personal case histories were taken. In addition, a detailed neurological physical examination, standard EEG and auditory evoked potentials, and a psychiatric examination were performed during several appointments. The results showed that disturbances in speech comprehension were more frequent in boys, and that in 13.4% of cases it was caused by pervasive developmental disturbances and in 41.24% of cases by external stimulating factors of speech development (pedagogy, social and emotional stimulation and growing up in a multilingual community). The study emphasizes the importance of non-verbal methods for the study of speech and the use of auditory evoked potentials.

Brain stem evoked potentials and visual evoked potentials in relation to the length of occupational exposure to low levels of toluene.

In 49 printing-press workers occupationally exposed to toluene for approximately 21.6 years, the values of BEAP and VEP parameters were examined in relation to the length of exposure. With the exception of P2 wave, there was a significant increase in the latencies of all the BEAP waves examined as well as in the interpeak latency (IPL) P3-P4, whereas IPL P4-P5 decreased significantly with the length of exposure. The amplitude of all the VEP examined decreased significantly with the length of exposure. Toluene exposure was evaluated by measuring the concentration of toluene in peripheral blood and of hippuric acid in urine on Wednesday morning prior to the workshift, and of hippuric acid in urine after the workshift on the same day. According to the average concentration of hippuric acid in urine after the workshift, the levels of toluene exposure were estimated to range from 40-60 ppm. Evoked potentials were determined on Mondays 10-12 hours after a nonworking weekend.

Cognitive evoked potentials VEP P300 persons occupationally exposed to low concentrations of toluene.

Cognitive evoked potentials VEP P300 were examined in 49 workers at printing press occupationally exposed to low concentrations of toluene for averagely 20 years, and in 59 control subjects. The exposure level of toluene was evaluated in randomly selected subgroups comprising 36 exposed and 27 control subjects. The concentrations of toluene were measured in peripheral blood on Wednesday morning before entering the work area, while the hippuric acid in urine was measured before and after entering the work area. The results show that the absolute number of exposed subjects displaying lower amplitude of cognitive wave VEP P300R and prolonged latency of the accompanying spontaneous wave VEP P300F was significantly greater than that of the controls.

Brainstem auditory evoked potentials in individuals exposed to long-term low concentrations of toluene.

Brainstem auditory evoked potentials (BAEPs) were examined in 49 workers employed in a printing press, who were occupationally exposed to low concentrations of toluene for an average of 20.3 years, and in 59 subjects in a control group. In the group of exposed workers, a significant decrease was found in all wave amplitudes examined, a significant prolongation of P1 wave latency, and an increased interval of interpeak latencies (P3-P5), indicating that the extramedullary and high medullary part of the auditory pathway are biologically most frequently affected by chronic exposure to low concentrations of toluene. The level of exposure to toluene in both groups was evaluated by defining the concentration of toluene in peripheral blood and the concentration of hippuric acid and ortho-cresol in urine.

Visual evoked potentials in individuals exposed to long-term low concentrations of toluene.

An investigation of visual evoked potentials was carried out in two groups of subjects; 49 workers employed in a printing-prss where toluene has been used exclusively as an organic solvent for the last 30 years, and 59 workers not occupationally exposed to any known neurotoxic substances. The average length of work service in the printing-press was 21.4 years. The level of exposure was assessed by determination of the concentration of toluene in peripheral blood, the concentration of hippuric acid and ortho-cresol in urine in subgroups of subjects chosen at random from both groups. N75, P100 and N145 waves of the pattern reversal visual evoked potentials were analyzed. In the group of exposed subjects, significantly greater amplitudes were found in all waves, with significantly longer latency of the P100 wave.

Genetic markers in the blood of multiple sclerosis patients.

Poligenetically determined predisposition to multiple sclerosis (MS) defines the way of immunological reaction to environmental factors and leads to clinically manifest disease. Although the connection between MS and some loci of the HLA system has been established, the hereditary predisposition to MS remains to be elucidated. We determined the phenotypes of monogenic hereditary characteristics linked to the surface of red blood cells that were obtained from 45 MS patients and 458 healthy subjects. The antigens on the erythrocytic surface of the ABO, Rh, MN, Ss, Kell, Kidd, Duffy, P and Lewis system were analyzed. Our results demonstrate that the MS patients differ from the normal subjects with regard to the Rh, ABO and Lewis erythrocytic antigens. The Rh positive factor was present in 95.55% of the MS patients compared to 84.29% of the controls, whereas the Rh negative factor was found in only 4.45% of the MS patients and 15.71% of the healthy subjects. The blood group O was demonstrated in 22.22% of the MS patients compared to 40.42% of the healthy persons. The MS patients had the blood group A in 15.11% of the cases as opposed to 43.99% of the subjects in the control groups. The blood group B was found in 22.22% of the MS patients compared to 11.10% of the controls. The distribution of the Lewis system in the MS patients was also demonstrated to be different from that in the general population. The MS patients were found to have less frequently the Le a+b- phenotype (11.12%) and more frequently Le a- b- (13.33%) compared to the healthy subjects who had the Le a+b- phenotype in 12.00% of the cases and Le a- b- in 5.00%.

Brain shunts in patients with stroke: possible cerebral autoregulation of changed haemodynamics.

The cerebral perfusion was evaluated in 8 patients with stroke, caused by stenosis or occlusion of the carotid artery, and in 4 neurologically healthy subjects, using Tc99m labeled microspheres (LMS). By measuring activity in the brain and lungs after intracarotid injection of LMS, the existence of brain shunts in patients with stroke was demonstrated. It seems that brain ischaemia triggers the opening of shunts which appear to be one of the important autoregulatory and protective mechanisms to cerebral haemodynamic changes after brain infarction.

Epileptic seizures as a symptom of various neurological diseases.

The authors evaluate the most frequent causes of seizures in 562 patients admitted at the emergency out-patient ward because of fits. 194 patients were admitted because of the first occurrence of seizures, in 12 of them the first manifestation was status epilepticus of the generalized (8), or focal type (4). The commonest causes of seizures were alcoholism (82), disturbances of the brain blood flow (74), posttraumatic states (20), brain tumor (4), or encephalopathies. In 11 patients the cause of seizures was not found. Besides the causes, the authors stressed the most frequent type of seizures, as well as therapeutic measures. They pointed out that in alcoholism generalized seizures, and grand mal status were the commonest expression of seizures. The same was found in patients with posttraumatic seizures, but they mostly suffered single attacks, and the same in encephalopathies. In patients with vascular lesions focal seizures were not rare. The antiepileptic therapy is not applied in the first occurrence of convulsions, therapy is causal, linked primarily to basic etiopathogenic mechanism responsible for triggering seizures.

Hereditary antigen characteristics of blood in ischemic cerebrovascular accident.

In order to determine genetic differences between 50 examinees with ischemic cerebrovascular accident (iCVA) and those of comparative group, we have chosen 1883 persons from phenotypic healthy population divided into 5 different subgroups. The purpose of our investigation was exploring hereditary characteristics of antigenes linked to erythrocyte membrane. The highest discriminating value in genetic distance had MN and ABO genetic loci. The frequency of M antigen in stroke patients was 70% (in the comparative group 55%), N antigen had frequency 30% in patients with iCVA and 45% in the comparative group. The frequency of the blood group A in the patients with iCV was 32.68% and 27.16% in the comparative group. Blood group B had frequency in the patients 10.69% and in the comparative group 6.72%. O blood group had frequency in the patients 56.73% and in the comparative group 66.12%. Genetic distance between patients with iCVA and the comparative group were determined with gene frequencies, that was shown on the dendrogram. The dendrogram clearly shows that patients with iCVA are separated from all other comparative subgroups. The results of our investigation presented the highest discriminating value of MN and ABO genetic loci. The possibility of linkage between genetic loci for these erithrocyte antigenes (on the 4th and 9th chromosome) and genetic loci which determine iCVA cannot be excluded. Finally we consider that this method can support earlier identification of persons who belong to "high risk group for cerebrovascular disease".

Haemodynamic changes in patients with subarachnoid haemorrhage assessed by Tc99m labeled albumin microspheres.

The aim of the present study was the investigation of haemodynamic changes in the brain in patients after subarachnoid haemorrhage (SAH) using Tc 99 m labelled albumin microspheres (LMS). Twenty-nine patients after SAH (13 in the acute and 16 in the chronic stage of the disease) and four neurologically healthy subjects were examined. LMS were injected in the carotid during angiography and brain and lung scintigrams were taken using gamma camera. In the control subjects a diffuse and uniform distribution of the activity in the brain was found. In the patients with acute SAH "patchy", nonhomogenous distribution of the activity was found, ranging up to the regional absence of perfusion. This pattern was observed in the chronic stage as well, but less obvious than in the acute. In all the patients the evident trapping of LMS in the lungs was demonstrated confirming brain shunts, absent in the control group. By measuring the activity in the brain and lungs after intracarotid injection of LMS, haemodynamic changes in the patients after SAH were proved and the existence of brain shunts was demonstrated. It seems that shunts are functional anastomoses and important protective mechanism, opening when cerebral haemodynamics is altered.

[Neurologic and urodynamic characteristics of patients with Guillain-Barré syndrome]. / Neuroloske i urodinamske osobine u bolesnika s Guillain-Barréovim sindromom.

Neurologic and urodynamic aspects of five patients with Guillain-Barré syndrome are presented. Four patients were urodynamically investigated in the acute stage of neurological disease. All of them had complete urinary retention. Following moments causing urinary retention were determined: detrusor areflexia with the signs of urethral sphincter denervation in one patient, detrusor hyperreflexia with dyssinergia of the sphyncter in two patients and detrusor hyperreflexia with synergia of the sphincter in one patient. One patient was examined in the chronic stage of Guillain-Barré syndrome showing urodinamically detrusor hyperreflexia with synergia of sphincter.