PubMed Health⌕ Search

Biomedical subjects

E Durán

Publications and source records attributed to E Durán.

At least 19 recordsLinked to original sources

Hallmarks of a common forebrain vertebrate plan: specialized pallial areas for spatial, temporal and emotional memory in actinopterygian fish.

In mammals and birds different pallial forebrain areas participate in separate memory systems. In particular, the hippocampal pallium is implicated in spatial memory and temporal attribute processing, whereas the amygdalar pallium is involved in emotional memory. Here we analyze the involvement of teleost fish lateral and medial pallia, proposed as homologous to the hippocampus and amygdala, respectively, in a variety of learning and memory tasks, such as spatial memory; reversal learning; delay or trace motor classical conditioning; heart rate, emotional classical conditioning; and two way active avoidance conditioning. Results show that the damage to the lateral pallium produces a profound deficit in spatial learning and memory in teleost fish. In addition, lateral pallium lesions produce a significant deficit in trace classical conditioning, whereas they have no significant effects on delay conditioning, or in heart rate conditioning. In contrast, medial pallium lesions disrupt emotional, heart rate conditioning and avoidance conditioning, but spare spatial memory and temporal stimulus processing. These data demonstrate a striking functional similarity between the medial and lateral pallia of teleost fish and the pallial amygdala and hippocampal pallium of land vertebrates, respectively. The reviewed evidence suggest that these two separate memory systems, the hippocampus-dependent spatial, relational or temporal memory system, and the amygdala based emotional memory system, could have appeared early during evolution, having conserved their functional identity through vertebrate phylogenesis.

Animals↗

Cognitive and emotional functions of the teleost fish cerebellum.

Increasing experimental and neuropsychological evidence indicates that the cerebellum of humans and other mammals, traditionally associated with motor control, is implicated in a variety of cognitive and emotional functions. For example, the cerebellum has been identified as an essential structure in different learning processes, ranging from simple forms of associative, sensory-motor learning and emotional conditioning, to more complex, higher-order processes such as spatial cognition. Although neuroanatomical and neurophysiological data indicate that the organization of the cerebellum is notably well conserved in vertebrates, little is actually known about the cerebellar contribution to processes besides the motor domain in non-mammals. In this work, we analyzed the involvement of the teleost fish cerebellum on classical conditioning of motor and emotional responses and on spatial cognition. Cerebellum lesions in goldfish impair the classical conditioning of a simple eye-retraction response analogous to the eyeblink conditioning described in mammals. Single unit extracellular electrophysiological recording and cytochrome oxidase histochemistry also reveal the involvement of the teleost fish cerebellum in classical conditioning. Autonomic emotional responses (e.g., heart rate classical conditioning) are also impaired by cerebellum lesions in goldfish. Furthermore, goldfish with cerebellum lesions present a severe impairment in spatial cognition. In contrast, cerebellum lesions do not produce any observable motor deficit as indicated by the swimming activity or obstacle avoidance and do not interfere with the occurrence of unconditioned motor or emotional responses. These data indicate that the functional involvement of the teleost cerebellum in learning and memory is strikingly similar to mammals and suggest that the cognitive and emotional functions of the cerebellum may have evolved early in vertebrate evolution, having been conserved along the phylogenetic history of the extant vertebrate groups.

Animals↗

Macrolide resistance phenotypes of commensal viridans group streptococci and Gemella spp. and PCR detection of resistance genes.

One hundred and sixty viridans group streptococci (VGS) and 26 Gemella spp. resistant to erythromycin were studied to detect macrolide lincosamide and streptogramin B (MLS(B)) phenotypes and to investigate resistance rates to other antibiotics. The M phenotype was most prevalent in both bacterial groups (59.6% in VGS, 69.2% in gemellae) and the iMLS(B) phenotype was found least often (9.3 and 13.9%, respectively). All isolates with M phenotype had the mef(A/E) gene, being prevalent the mef(E) subclass. cMLS(B) and iMLS(B) strains contained the erm(B) gene, alone or in combination with the mef(A/E) gene. Thirteen isolates were intermediately resistant to quinupristin/dalfopristin and 11 strains showed low susceptibility to telithromycin. Linezolid was active against all the isolates tested and tetracycline resistance was the major one in VGS (41.6%) and Gemella spp. (46.2%).

Acetamides↗

[HIV related Foix-Chavany-Marie syndrome].

Automatic-voluntary motor dissociation of the face and lower cranial nerves of brainstem is the hallmark of Foix-Chavany-Marie syndrome (biopercular syndrome). It is commonly caused by ischemic strokes. We present a biopercular syndrome associated with HIV. A 41 year old female who presents a progressive automatic- voluntary motor dissociation of face and lower cranial nerves with later involvement of limbs. She was immunodepressed as a result of HIV. MRI showed bilateral lesions in opercular areas and ventrolateral thalamic nucleus, likely as a result of retrograde neuronal degeneration. Automatic-voluntary dissociation occur after biopercular lesions with sparing of motor pathway proceeding from the cingulate cortex.

Adult↗

Lesions induced by 2,4-D and chlorpyrifos in tench (Tinca tinca L.): implication in toxicity studies.

This study was undertaken to demonstrate the toxicity of two pesticides, chlorpyrifos (O,O-diethyl 0-3,5,6-trichloro-2-pyridyl phosphorothioate) and 2,4-D (Dichlorophenoxyacetic acid) to tench (Tinca tinca Linnaeus). Pathological samples of damaged tench kidney showing lesions were taken for statistical analysis in order to quantify different parameters. Analysis revealed differences in the action and/or action time of the two pesticides. These differences were more acute in the case of 2,4-D thereby indicating a greater toxicity. These differences, expressed by mathematical formulae of numerical variables, would enable, a priori, the identification of the responsible pesticide and the time of acting in new natural cases of poisonings with these substances.

2,4-Dichlorophenoxyacetic Acid↗

[Usefulness of olanzapine in the levodopa-induced psychosis in patients with Parkinson's disease].

BACKGROUND: To evaluate the antipsychotic efficacy of olanzapine (OLZ) in patients with Parkinson's disease (PD) and drug-induced psychosis (DIP) and its repercussion on the motor function. METHODS: Ten patients (5 women and 5 men) diagnosed of PD and DIP, aged 67 years (range: 50-81), with PD duration of 11.1 years (range: 6-23), treated chronically with levodopa per day, received a dose of 2.5 or 5.0 mg OLZ daily. Data concerning improvement of psychosis and worsening of motor function was based on Positive And Negative Symptoms Scale (PANSS) and Unified Parkinsons Disease Rating Scale (UPDRS) motor. RESULTS: Psychotic symptoms were improved in all patients. In most of them the improvement was almost total. Seven patients increased levodopa dose on OLZ, but significant worsening of motor function was reported just in one patient. None of the patients had agranulocytosis in the blood monitoring. Two patients presented weight gain. Seven patients improved their cognitive status. CONCLUSIONS: We conclude that OLZ at the doses studied may have efficacy for DIP which appears in PD and does not induce worsening of motor function in most of the patients.

Aged↗

Histoplasmosis and Paracoccidioidomycosis in northwestern Argentina III. Epidemiological survey in Vipos, La Toma, and Choromoro - Trancas, Tucumán, Argentina.

The present work was undertaken to obtain epidemiological data on the extent and distribution of Histoplasma capsulatum var. capsulatum and Paracoccidiodes brasiliensis diseases in the Vipos, La Toma and Choromoro areas. Skin test surveys with histoplasmin and paracoccidioidin were carried out in the permanent human population of those localities. Mycological sputum studies and serological tests were performed to skin test reactors to determine if there were signs or symptoms of active mycotic disease. La Toma and Choromoro are highly prevalent areas of histoplasmosis (>30% the histoplasmin positive individuals) whereas Vipos can be relatively considered a highly prevalent area (between 20-30% the histoplasmin reactors) according to the normally accepted range used to define an endemic disease [2]. Early Histoplasma capsulatum infection (<10 years old) is reported for Vipos and Choromoro. La Toma has the highest rate of previous exposure to P. brasiliensis detected in the studied area (10.2%). Vipos residents are not infected with P. brasiliensis.

Adolescent↗

Acute 2,4-D poisoning in tench (Tinca tinca L.): lesions in the hematopoietic portion of the kidney.

An experimental model was designed to study the acute lesions caused by a continuous exposure to 2,4-dichlorophenoxyacetic acid (2,4-D) disolved in water (400 mg/L) in hematopoietic kidney tissue in tench (Tinca tinca L). Fifty fish were used in this study, 15 for calculating LC50 and 35 were euthanized 1, 2, 5, 8, and 12 days postpoisoning (five treated and two controls each time). Tissue samples, fixed in 5% glutaraldehyde in 0.1 M phosphate buffer (pH 7. 2) for histopathological examination, revealed marked alteration of hematopoietic tissue, characterized by progressive swelling and cell necrosis, activation of the phagocyte system, and subsequent formation of myelin figures. Variations recorded in hematocrit and hemoglobin levels in blood samples indicated changes in membrane permeability, complementing the findings on hematopoietic tissue. The lethal dose (LC50) at 96 h demonstrated the importance of the species and chemical form used as factors in calculating a product's toxicity.

2,4-Dichlorophenoxyacetic Acid↗

[Tuberculosis in recent immigrants in Barcelona].

BACKGROUND: The aim of the present was to study the prevalence of infection and tuberculous disease as well as the fulfillment of secondary antituberculin chemoprophylaxis in immigrants according to their geographic origin. PATIENTS AND METHODS: A descriptive study was carried out of 1,489 immigrants under the age of 35 years attended in the Tropical and Imported Disease Unit Drassanes in Barcelona, Spain from 1989 to 1994. RESULTS: The patients were from 79 countries, with 81.7% being males and 18.3% females (p < 0.001) of a mean age 26.1 +/- 5.7 and 23.4 +/- 7.5 years, respectively. Forty-three percent of the cases presented Mantoux test response > or = 10 mm of induration. The highest percent of positivity was observed in patients from Subsaharian Africa (52%) followed by Eastern Europeans and Asians (44%), South and Central Americans (38%) and Middle East and Northern Africa (34%) (p < 0.001). Thirty-nine percent of the 359 patients who initiated secondary antituberculin chemoprophylaxis completed the 6 months of treatment with the highest fulfillment being found in Africans (49%) followed by Americans (42%) and Asians (39%). The lowest rate was observed in the Eastern Europeans (20%) (p < 0.001). Fifty-six percent of the patients abandoned secondary antituberculin prophylaxis within the first three months. Eighteen cases of active tuberculosis were diagnosed. CONCLUSIONS: The prevalence of tuberculous infection and disease is high immigrants in Barcelona, Spain. The fulfillment of chemoprophylaxis is low and abandoned early. These facts should be evaluated when designing prevention and control programs.

Adult↗

Spatial learning and memory deficits after telencephalic ablation in goldfish trained in place and turn maze procedures.

The present work investigated whether the fish telencephalon is involved in spatial learning based on place strategies in a manner similar to mammalian hippocampus. Goldfish were trained in a 4-arm maze in a room with relevant spatial cues. Sham and to-be-ablated subjects were trained in each of 4 experimental procedures designed as follows: place, turn, place-turn, and control. After acquisition, complete ablations of both telencephalic hemispheres for the experimental groups were carried out. The results showed that ablation exclusively impaired performance in animals using place strategies; in these, accuracy fell to chance level during both postsurgery retraining and reversal periods. In the other groups, ablation of the telencephalon did not induce any significant deficit. These results suggest that the fish telencephalon plays a crucial role in complex place learning.

Animals↗

[Malaria imported by immigrants in Catalonia].

BACKGROUND: The aim of the present study was to analyze the epidemiologic aspects and particular features of malaria in immigrants in Catalonia, Spain. METHODS: All the immigrants who visited the Unit of Tropical and Imported Diseases "Drassanes" in Barcelona from endemic zones of malaria from 1990 to 1993 were studied. The diagnosis of malaria was based on the thick blood film, peripheral blood smear exam and, since 1991, the QBC (Quantitative Buffy Coat). RESULTS: One hundred three cases of malaria were diagnosed in 100 individuals from a total of 2,453 visited immigrants. Forty-four percent of the patients presented febrile syndrome, 11% cutaneous syndrome accompanied by other manifestations justifying the same, 9% presented other clinical manifestations and 36% were asymptomatic. Ninety-six percent of the subjects with parasites by Plasmodium were from sub-Saharan Africa and in 2 cases, both were produced by Plasmodium falciparum, with the length of time having been in Spain at the time of diagnosis being more than one year. P. falciparum represented 70% of the total cases, followed by P. malariae (15%), P. vivax (8%), Plasmodium spp. (6%) and P. ovale (1%). CONCLUSIONS: Malaria by P. falciparum in semi-immune immigrants is not usually severe and follows an asymptomatic course in more than one third of the cases. The usual analysis for Plasmodium is recommended in immigrants from sub-Saharan Africa due to the high frequency of presentation and the absence of symptoms. Such analysis is not advised in groups from other areas except when suggestive symptoms are present.

Adolescent↗

Experimental reproduction of acute pneumonic pasteurellosis in rabbits.

A histomorphometric and physiopathological study was made of the lung parenchyma of Belgian White SPF rabbits infected experimentally with Pasteurella multocida type A. Symptoms observed were characteristic of the acute respiratory syndrome. Mean serum cortisol concentration and rectal temperature increased in all experimental groups. Histopathological changes included alveolitis and leukocytic bronchitis. Changes in alveolar and bronchial cytoarchitecture were attributed to the degeneration and necrosis of constituent epithelial cells.

Acute Disease↗

Morphometric, structural, and ultrastructural studies of tench (Tinca tinca L.) hepatocytes after copper sulfate administration.

A structural, ultrastructural, and morphometric study was made of the liver parenchyma of 12 adult tench (Tinca tinca, L.) subjected to acute experimental copper sulfate poisoning. The lesions observed were characterized by the accumulation in the cytoplasm of large amounts of hemoglobinemic pigment produced by intense hemolysis, initially in Kupffer cells and by the last stage of the experiment in hepatocytes. This process became increasingly severe, and culminated in the massive necrosis of large areas of liver parenchyma, which led to the death of tench 12 days after the start of the experiment.

Animals↗