From deep dyslexia to agrammatic comprehension on silent reading

We report on a case of a French-speaking patient whose performance on reading aloud single words was characteristically deep dyslexic (in spite of preserved ability to identify letters), and whose comprehension on silent sentence reading was agrammatic and strikingly poorer than on oral reading. The first part of the study is mainly informative as regards (i) the relationship between letter identification, semantic paralexias and the ability to read nonwords, (ii) the differential character of silent and oral reading tasks, and (iii) the potential modality-dependent character of the deficits in comprehension encountered. In the second part of the study we examine the patient's sensitivity to verb-noun ambiguity and probe her skills in the comprehension of indexical structures by exploring her ability to cope with number agreement and temporal and prepositional relations. The results indicate the patient's sensitivity to certain dimensions of these linguistic categories, reveal a partly correct basis for certain incorrect responses, and, on the whole, favor a definition of the patient's disorders in terms of a deficit in integrating indexical information in language comprehension. More generally, the present study substantiates a microgenetic approach to neuropsychology, where the pathological behavior due to brain damage is described as an arrest of microgenesis at an early stage of development, so that patient's responses take the form of unfinished "products" which would normally undergo further development

Experimental model studies of pesticide exposure

The neurotoxic effects of Dimethoate (Dim), Dichlorvos (DDVP) and Methyl-Parathion (MP) respectively were investigated on the central nervous system (CNS) and peripheral nervous system (PNS) of rats after different treatment schedules at the macro and single unit cell level. At the macro investigations 1/25, 1/50 and 1/100 of the respective LD50 values of each pesticide were administered to different groups by garage daily in the following programs: Pregnancy variation (P) to females from 5th to 15th days of pregnancy; Pregnancy and lactation variation (P+L): to females as above and during lactation for 4 weeks; Pregnancy+lactation+post weaning variation (P+L+P) as above plus to the young male rats (F1 generation) up to 8 weeks. Neurotoxicological investigations were conducted on the F1 rats at the age of 12 weeks. Spontaneous electrocorticograms (ECoG) were recorded on the anesthetized rats from the somatosensory, visual and auditory cortex. Cortical evoked potentials (EP) were recorded from the same areas subsequently. Conduction velocity and refractory periods of the tail nerve was investigated. Treatment by Dim, DDVP and MP during P and P+L of the mothers did not influence the bioelectric activity of the offsprings significantly. The same treatment by the P+L+P programme, resulted in significant changes. Frequency of the spontaneous ECoG waves grew significantly in all dose groups of P+L+P group. Latency time become shorter after somatosensory, light or acoustic stimuli respectively on one hand and the beginning of the of answer of these by the evoked potential (EP) waves on the other hand. Conduction velocity of the tail nerve diminished, refractory periods grew dose dependently and significantly at the P+L+P programs with all the three pesticides. Cortical single unit activity was studied after the i.p administration of 1/5 LD50 of the three organophosphates (OP). The decrease of the firing frequencies was observed. The amplitude of the hippocampal population spikes increased. The changes observed in these studies point toward a higher excitation state of the CNS and a disturbed conduction of the nervous impulses of the peripheral nerves. These results could be taken into consideration when deciding on human contaminations by OP-s

Effect of acute administration of certain heavy metals and their combinations on the spontaneous and evoked cortical activity in rats

The aim of this study was to see the effect of acutely administered inorganic lead, mercury, manganese, and their combinations, on the electrical activity in the somatosensory system of rats. Male Wistar rats were anaesthetised with urethane, the head was fixed in a stereotaxic frame and the left hemisphere was exposed. Weak electric shocks to the whiskers and the tail served as stimuli. Spontaneous and stimulus-evoked activity was recorded from the primary projection area of the whiskers and the tail. After an hour of control recording, one of the following was given to the rat i.p.: 1000 mg/kg Pb2+, 7 mg/kg Hg2+, 50 mg/kg Mn2+, 500 mg/kg Pb2+ + 25 mg/kg Mn2+, or 500 mg/kg Pb2+ + 3.5 mg/kg Hg2+. Lead caused a massive increase in the cortical response amplitude, starting immediately after administration and developing in the next 40-50 min. Latency showed a minimal increase. The spontaneous activity was moderately shifted to lower frequencies. The effect of Hg2+ on the response amplitude and on the ECoG was similar but stronger than that of Pb 2+. The effect of Mn2+ on the evoked activity was marked but less strong than with Pb2+. The ECoG shift was moderate. With Hg2+ and Mn2+, the response amplitude showed first a decrease than an increase. The effect of the Pb2+ + Mn2+ combination on the activities was not additive but the correlation between the alteration of the ECoG and the evoked potential was stronger than with any of the metals alone. With Pb2+ + Hg2+, the effect of Pb 2+ dominated on the evoked and that of Hg2+ on the spontaneous activity. In the peripheral nerve, action potential amplitude and conduction velocity were decreased. These alterations of the spontaneous and stimulus-evoked cortical activity probably reflected a specific action of the heavy metals on the nervous activity. Š 2004 Elsevier B.V. All rights reserved

Különböző kémiai szerkezetű peszticid hatóanyagok - szerves foszfát, piretroid, karbamát, klórozott szénhidrogén, tercier-aromás-triamin - és kombinációik által kiváltott neuro-, magatartás- és immuntoxikológiai hatások vizsgálata állatkísérletes modellekben = Investigation of neuro-, behavioural and immuntoxicological effects caused by single and combined treatment of pesticides of different chemical structure (organophosphate, pyrethroide, carbamate, chlorinated hydrocarbone, tertial-aromatic-triamine)

Inszekticidek (dimetoát, propoxur, cipermetrin, amitraz) önálló ill. kombinált szubkrónikus bevitelével vizsgáltuk felnőtt patkányok immunrendszerének ill. idegrendszerének; valamint akut ill. az intra- és extrauterin egyedfejlődés során való adást követően az idegrendszer működését. Az anyagok jellemzői és alkalmazása valószínűsítik egyidejű jelenlétüket és hatásukat az emberi szervezetben. Neurotoxicitás: Az amitráz esetében igazoltuk a neurotoxicitást. A dimetoát és az amitráz hatásai eltérő hatásmechanizmus mellett hasonlóak, a dimetoát és propoxur hatásai hasonló hatásmechanizmus mellett eltérőek voltak. A dimetoát és az amitráz kombinációs kezelésekben is dominált. A spontán kérgi aktivitás változásai több hatóanyag esetében ellentétesek voltak pre- ill. pre- és posztnatális adagolásnál; a kérgi kiváltott válaszok változásai a pre- és posztnatális expozíció összeadódó hatását jelezték. A kiváltott aktivitás változásai voltak pontosabban értékelhetők. Általános és immuntoxikus hatások: A hatások közül a relatív szervtömegek és egyes hematológiai paraméterek voltak legérzékenyebbek az inszekticidekre. A kezelés időtartamának hatása itt is jelentős volt. Az általános, neuro- ill. immuntoxikológiai eredmények között nem volt minden hatást és kölcsönhatást jól jelző paraméter. Az eredmények hozzájárulhatnak az expozíciós határértékek finomításához. Egyes funkcionális eltérések eléggé érzékenyek és specifikusak ahhoz, hogy a későbbiekben biomarkerré váljanak. | Effects of insecticides (dimethoate, prpopxur, cypermethrin, amitraz) was studied, alone or combined, on the nervous and immune system of adult rats in subchronic exposure, and on the nervous system in acute dosage or in exposure including pre- and postnatal development. The agents' characteristics and usage make their simultaneous presence and effects in humans likely. Neurotoxic effects: Neurotoxicity of amitraz was verified. Effects of dimethoate and amitraz were like, despite different way of action, and those of dimethoate and propoxur were unlike, despite similar way of action. Effects of combinations were dominated by dimethoate or amitraz. Changes of spontaneous cortical activity were with several agents opposite when given only in the prenatal, than when in the pre- and postnatal period. Evoked responses, however, indicated an additive effect of pre- and postnatal exposure. The changes of the evoked activity were to evaluate more accurately. General and immuntoxicological parameters: Of all effects, the changes of relative organ weights and certain haematological parameters were the most sensitive to the insecticides. The length of exposure had a major effect also here. None the general, neuro- and immuntoxicological outcomes indicated all effects and interactions. The results can contribute to refining exposure limit values. Some functional alterations were sensitive and specific enough to be developed to biomarkers

Experiences of testing dietary supplements

Determination of the prohibited active ingredients, such as drugs and their designer compounds, of dietary supplements products intended for athletes is an important, but not yet well-known and regulated area of food analysis. In our laboratory, the analysis of three major product groups is carried out. The first group includes products intended for athletes. They can be dietary supplements or a group of products that had been classified as foodstuffs for particular nutritional uses before 2016, for example, high protein content products promoting great muscular effort, intended primarily for athletes and workers performing heavy labor, which were transferred to the category of dietary supplements or normal foods after 2016. For athletes, when consuming the products, in addition to preserving health and the physiological effects to be achieved, it is important that the products do not contain even trace amounts of substances that are on the prohibited list of WADA (the World Anti-Doping Agency), because they are solely responsible for the presence of these in their bodies. The second group is that of weight loss products. Regarding the prohibited substances used in dietary supplements, products belonging to this group show a high degree of similarity to the group of products containing stimulants prohibited for athletes. The third group consists of products used for the treatment of sexual dysfunctions. In these, phosphodiesterase inhibitors, widely known as drugs, may be present as prohibited active ingredients or contaminants. The most common ingredients of these products include plant extracts. In all three cases, the extent of contamination may vary widely in the groups examined, from trace amounts to pharmaceutical active ingredient levels. 12 years ago, when the analysis of products has been started at our laboratory intended for athletes, our objective was to develop screening analytical methods that are able to determine prohibited stimulants with detection limits of 100 ng/g and anabolic agents with detection limits of 10 to 50 ng/g efficiently, in a robust way, with sufficient measurement (detection) accuracy. The analysis of potency enhancers was launched three years later. Since the initial analysis of 40 components, the number of types and components of active ingredients analyzed has increased significantly and, in addition, in the case of stimulants and narcotics, the detection limit improved to 10 ng/g. Currently, accredited analysis of 126 prohibited ingredients is performed in the laboratory. During this time, more than 10,000 raw materials and finished products have been tested. For the analysis of anabolic agents, hormone and metabolic modulators, GC-MS and LC-MS/MS methods have been used, while LC-MS/MS techniques have been used for the determination of stimulants, narcotics, beta-blockers, beta2 agonists and potency enhancers, following appropriate sample preparation. In our manuscript, of the compound groups examined in the laboratory, the analyses of anabolic agents and aromatase inhibitors, which belong to the group of hormone and metabolic modulators, are presented, in products intended for athletes and their raw materials. It should be noted that for the names of the compounds in dietary supplements contained in this paper, the Anglo-Saxon version common in international practice is used

"Condoms Are Reliable but I Am Not": A Qualitative Analysis of AIDS-Related Beliefs and Attitudes of Young Heterosexual Adults in Budapest, Hungary and St. Petersburg, Russia

HIV and STD prevention is an essential component of public health initiatives in countries throughout Central and Eastern Europe. Liberalization in sexual values, declining age at first sex, higher levels of sexual activity, and inconsistent condom use have been well-documented among young people in the region following the political, economic, and cultural transitions after the end of the state socialism era. Less well-understood are the reasons for high-risk sexual behavior and psychosocial factors that must be addressed in the development of effective HIV/STD prevention programs. This study recruited members of 12 high-risk social networks of young adult men and women (n= 66 participants) in two cities, St. Petersburg, Russia, and Budapest, Hungary. In-depth focus groups were conducted with all members of each network, and qualitatively analyzed to examine factors surrounding high-risk sexual behavior. Main themes that emerged were that STDs are less known and less feared than AIDS, HIV risk factors were relatively well known among young adults in both countries but vulnerability is perceived differently, pregnancy prevention is a more immediate concern than protection from HIV or STDs, condom use declines quickly following first sex with a new partner, reintroducing condom use in a relationship is very difficult, and young adults report many barriers to condom use including those related to alcohol or other substance use. HIV/STD prevention programs are needed that extend beyond risk education alone and that also address critical psychological, social, and relationship factors related to sexual risk behavior