Trastornos de la salud mental en personas sometidas a cuarentena, estudio transversal durante pandemia por COVID-19 en población chilena / The effects of quarantine on anxiety and emotional symptoms. Results of an online survey

BACKGROUND: Quarantines may exacerbate the presence of emotional symptoms or anxiety. AIM: To explore the relation between time spent in lockdown and development of depressive and anxiety symptoms. MATERIAL AND METHODS: A survey including the GAD anxiety and PHQ-9 depression scores was answered online by 1,488 subjects aged 36 ± 14 years (74% women), invited to participate through social networks. Both scores are validated for the Chilean population. RESULTS: Most responders had a private health insurance system. Sixty seven percent had clinically significant depressive symptoms and 39% had anxiety symptoms. Spending four or more weeks of lockdown (quarantine) was associated with 1.6 times higher risk of developing depressive symptoms and 2.9 times higher risk of developing anxiety symptoms. Difficulties in access to health care increased 3.3 times the risk of developing depression. Suffering a respiratory disease increased 2.39 times the risk of developing anxiety. CONCLUSIONS: There was a direct association between depressive and anxious symptoms, and the time spent of quarantine.

Prevalencia de comorbilidad depresiva en la enfermedad de Ménière

Resumen Introducción: Existe relación entre la enfermedad de Ménière (EM) y los trastornos psiquiátricos. Objetivo: Evaluar si los pacientes con EM presentan mayor prevalencia de comorbilidad depresiva en comparación a lo descrito para la población general nacional. Material y Método: Estudio analítico transversal entre los años 2009-2016, en pacientes del Servicio de Otorrinolaringología del Hospital Barros Luco Trudeau con diagnóstico de EM definitivo. Se aplicó la escala del nivel funcional para EM, tinnitus handicap inventory, test de tamizaje de depresión de Goldberg y una evaluación por psiquiatra. Resultados: Se evaluaron 64 pacientes. Promedio de edad fue 52,5 años. La prevalencia de trastorno depresivo fue 71,8%. De éstos, el 71,7% fue diagnosticado antes del estudio y el 28,3% restante durante el estudio. Conclusión: La prevalencia de comorbilidad depresiva en la EM es mayor que la descrita para la población general nacional. Determinar si la EM es la causante de esta prevalencia, o cada uno de sus síntomas por separado, requerirá de nuevos estudios.

Abstract Introduction: There is a relationship between Ménière's disease (MD) and psychiatric disorders. Aim: To assess whether MD patients have a higher prevalence of depressive comorbidity compared to that described for the national general population. Material and Method: Cross-sectional analytical study between 2009-2016, for patients seen at the Department of Otolaryngology at the Barros Luco Trudeau Hospital with a definitive MD diagnosis. The functional level scale was applied for MD, tinnitus handicap inventory, Goldberg screening for depression, and an evaluation by a psychiatrist. Results: 64 patients were evaluated. Average age was 52.5 years. The prevalence of depressive disorder was 71.8%. Of these, 71.7% were diagnosed before the study and the remaining 28.3% during the study. Conclusion: The prevalence of depressive comorbidity in MD is higher than that described for the national general population. Determine if MD or each symptom separately is the cause of this prevalence requires other studies.

Persistent meanders and eddies lead to quasi-steady Lagrangian transport patterns in a weak western boundary current.

The Brazil Current (BC) is a weak western boundary current flowing along the Southwestern Atlantic Ocean. It is frequently described as a flow with intense mesoscale activity and relatively low volume transport between 5.0 and 10.0 Sv. We use a 13-year eddy-resolving primitive-equation simulation to show that the presence of persistent meanders and eddies leads to characteristic quasi-steady Lagrangian transport patterns, aptly extracted through climatological Lagrangian Coherent Structures (cLCS). The cLCS position the surface expression of the BC core along the 2000-m isobath, in excellent visual agreement with high resolution satellite sea-surface temperature and the model Eulerian mean velocity. The cLCS deformation pattern also responds to zonally persistent cross-shelf SSH transition from positive (high) values near coastline to low (negative) values between 200- and 2000-m and back to positive (high) offshore from the 2000-m isobath. Zonally-paired cyclonic and anticyclonic structures are embedded in this transition, also causing the cLCS to deform into chevrons. An efficient transport barrier is identified close to the 200-m isobath confirmed by limited inshore movement of drogued drifters and accurately indicated by an along slope maxima of climatological strength of attraction. We also show that the persistent cyclonic and anticyclonic structures may induce localized cross-shelf transport. Regions of low climatological strength of attraction coincide with large shelves and with stagnant synthetic trajectories. We also show that cLCS accurately depict trajectories initiated at the location of Chevron's spill (November 2011) as compared to synthetic and satellite-tracked trajectories, and the outline of the oil from that accident. There is also an agreement between the large-scale oil slicks reaching the Brazilian beaches (from August 2019 to February 2020) and the strength of climatological attraction at the coast. Our work also clarifies the influence of persistent mesoscale structures on the regional circulation. The identification and quantitative description of climatological Lagrangian coherent structures is expected to improve the effectiveness of future emergency response to oil spills, contingency planning, rescue operations, larval and fish connectivity assessment, drifter launch strategies, waste pollutant and marine debris dispersion and destination.

Salmonella enterica Serovars Dublin and Enteritidis Comparative Proteomics Reveals Differential Expression of Proteins Involved in Stress Resistance, Virulence, and Anaerobic Metabolism.

The Enteritidis and Dublin serovars of Salmonella enterica are phylogenetically closely related yet differ significantly in host range and virulence. S Enteritidis is a broad-host-range serovar that commonly causes self-limited gastroenteritis in humans, whereas S Dublin is a cattle-adapted serovar that can infect humans, often resulting in invasive extraintestinal disease. The mechanism underlying the higher invasiveness of S Dublin remains undetermined. In this work, we quantitatively compared the proteomes of clinical isolates of each serovar grown under gut-mimicking conditions. Compared to S Enteritidis, the S Dublin proteome was enriched in proteins linked to response to several stress conditions, such as those encountered during host infection, as well as to virulence. The S Enteritidis proteome contained several proteins related to central anaerobic metabolism pathways that were undetected in S Dublin. In contrast to what has been observed in other extraintestinal serovars, most of the coding genes for these pathways are not degraded in S Dublin. Thus, we provide evidence that S Dublin metabolic functions may be much more affected than previously reported based on genomic studies. Single and double null mutants in stress response proteins Dps, YciF, and YgaU demonstrate their relevance to S Dublin invasiveness in a murine model of invasive salmonellosis. All in all, this work provides a basis for understanding interserovar differences in invasiveness and niche adaptation, underscoring the relevance of using proteomic approaches to complement genomic studies.

[The effects of quarantine on anxiety and emotional symptoms. Results of an online survey]. / Trastornos de la salud mental en personas sometidas a cuarentena, estudio transversal durante pandemia por COVID-19 en población chilena.

BACKGROUND: Quarantines may exacerbate the presence of emotional symptoms or anxiety. AIM: To explore the relation between time spent in lockdown and development of depressive and anxiety symptoms. MATERIAL AND METHODS: A survey including the GAD anxiety and PHQ-9 depression scores was answered online by 1,488 subjects aged 36 ± 14 years (74% women), invited to participate through social networks. Both scores are validated for the Chilean population. RESULTS: Most responders had a private health insurance system. Sixty seven percent had clinically significant depressive symptoms and 39% had anxiety symptoms. Spending four or more weeks of lockdown (quarantine) was associated with 1.6 times higher risk of developing depressive symptoms and 2.9 times higher risk of developing anxiety symptoms. Difficulties in access to health care increased 3.3 times the risk of developing depression. Suffering a respiratory disease increased 2.39 times the risk of developing anxiety. CONCLUSIONS: There was a direct association between depressive and anxious symptoms, and the time spent of quarantine.

Extracting quasi-steady Lagrangian transport patterns from the ocean circulation: An application to the Gulf of Mexico.

We construct a climatology of Lagrangian coherent structures (LCSs)-the concealed skeleton that shapes transport-with a twelve-year-long data-assimilative simulation of the sea-surface circulation in the Gulf of Mexico (GoM). Computed as time-mean Cauchy-Green strain tensorlines of the climatological velocity, the climatological LCSs (cLCSs) unveil recurrent Lagrangian circulation patterns. The cLCSs strongly constrain the ensemble-mean Lagrangian circulation of the instantaneous model velocity, showing that a climatological velocity can preserve meaningful transport information. The quasi-steady transport patterns revealed by the cLCSs agree well with aspects of the GoM circulation described in several previous observational and numerical studies. For example, the cLCSs identify regions of persistent isolation, and suggest that coastal regions previously identified as high-risk for pollution impact are regions of maximal attraction. We also show that cLCSs are remarkably accurate at identifying transport patterns observed during the Deepwater Horizon and Ixtoc oil spills, and during the Grand LAgrangian Deployment (GLAD) experiment. Thus it is shown that computing cLCSs is an efficient and meaningful way of synthesizing vast amounts of Lagrangian information. The cLCS method confirms previous GoM studies, and contributes to our understanding by revealing the persistent nature of the dynamics and kinematics treated therein.

Trasplante combinado hígado-riñón en la fundación valle del Lili, Cali, Colombia - Experiencia de un centro / The experience of the Fundacion Valle Del Lili in Cali, Colombia with Combined Liver and Kidney Transplantation

Introducción: el trasplante combinado de hígado y riñón (CLK) ha mostrado ser una buena alternativa para pacientes con diagnóstico concomitante de enfermedad renal crónica (ERC) y enfermedad hepática terminal. Algunos estudios han mostrado además un beneficio inmunológico del trasplante combinado, con disminución de la tasa de rechazo del injerto renal. Objetivo: describir las indicaciones y los resultados clínicos en receptores de trasplante CLK en un hospital de alta complejidad. Materiales y métodos: se seleccionaron los pacientes con trasplante CLK del registro institucional de trasplante (TRENAL) entre 2000 y 2011. Se describieron las características demográficas y clínicas y se estimó la sobrevida de los pacientes y de los injertos con el método Kaplan Meier. Resultados: en un período de 11 años, se realizaron 16 trasplantes CLK. Esto corresponde al 1.51% de los trasplantes de riñón y al 3.48% de los trasplantes de hígado hechos en la institución durante el mismo periodo de tiempo. La mayoría de los receptores fueron de sexo masculino (10/16). La mediana de la edad fue 56.5 años. La mediana del MELD fue de 17 (RIQ: 12.5-20.5, Rango 8-24). El diagnóstico hepático más frecuente fue cirrosis por NASH (4/16). Todos los pacientes tenían diagnóstico de ERC, en 4 casos secundaria a diabetes mellitus. Las indicaciones más comunes del trasplante fueron ascitis de difícil manejo, encefalopatía recurrente y desnutrición. El tiempo promedio de isquemia en frío del hígado fue de 7,3 horas, y del riñón 9,6 horas. La sobrevida de los pacientes y de los injertos hepático y renal fue de 87,5% al año y 67,3% a los 5 años. Cuatro pacientes murieron, 2 casos como consecuencia de sepsis y otros 2 por malignidad. Conclusión: el trasplante CLK en la Fundación Valle del Lili tiene resultados clínicos satisfactorios y comparables a los reportados en otros centros.

Introduction: Combined liver and kidney transplantation (CLK) has been shown to be a good alternative for patients with concomitant diagnosis of chronic kidney disease (CKD) and end-stage liver disease. Some studies have also shown immunological benefits from combined transplantation with decreased rates of kidney graft rejection. Objective: The objective of this study was to describe the indications and clinical outcomes of CLK transplant recipients in a highly complex hospital. Materials and Methods: CLK transplant patients were selected from the institutional transplant registry (Trenal) from 2000 to 2011. Demographic and clinical characteristics were described and survival of patients and grafts were estimated with the Kaplan-Meier method. Results: Over a period of 11 years, 16 CLK transplants were performed. This was 1.51% of kidney transplants and 3.48% of liver transplants done in the institution during this period. Most recipients were male (10/16). The median age was 56.5 years. The median MELD was 17 (IQR: 12.5 to 20.5, range: 8 to 24). The most frequent diagnosis was liver cirrhosis due to NASH (4/16). All patients had been diagnosed with CKD: four cases were secondary to diabetes mellitus. The most common indications for transplants were difficult to manage ascites, recurrent encephalopathy and malnutrition. The average liver cold ischemia time was 7.3 hours, and the average kidney cold ischemia time 9.6 hours. The five-year liver graft survival rate was 87.5%, and the five-year kidney graft survival rate was 67.3%. Four patients died: two as the result of sepsis and two as the result of malignancy. Conclusion: CLK transplantation results at the Fundación Valle del Lili have been satisfactory and comparable to those reported by other transplant centers.

Anti-inflammatory activity of Mitraphylline isolated from Uncaria tomentosa bark.

ETHNOPHARMACOLOGICAL RELEVANCE: Uncaria tomentosa (Willd. ex Roem. & Schult.) DC. (Rubiaceae) is widely used by populations living in South America to treat many ailments associated with inflammatory disorders. Mitraphylline was shown to be the major pentacyclic oxindolic alkaloid present in the bark chloroformic extract of this plant. Its activity against cytokines involved in inflammation process was tested in a murine model in vivo. MATERIALS AND METHODS: Mice received mitraphylline once a day for 3 days at 30 mg/kg/day by oral route. Then, they were subjected to bacterial lipopolysaccharide (LPS) endotoxin (15 mg/kg) and the LPS-induced production of 16 different cytokines was determined by Elisa multiplex. Control group received dexamethasone orally at 2mg/kg/day. Toxicity on K565 cells and murine peritoneal macrophages, in vitro, at doses up to 100 µM was monitored by XTT-colorimetric assay. RESULTS AND CONCLUSIONS: For the first time mitraphylline was tested in vivo against a large range of cytokines that play a crucial role in inflammation. Mitraphylline inhibited around 50% of the release of interleukins 1α, 1ß, 17, and TNF-α. This activity was similar to dexamethasone. It also reduced almost 40% of the production of interleukin 4 (IL-4) while the corticoid did not. Lastly it did not show any toxicity on K565 cells nor murine macrophages at doses up to 100 µM.

Small nuclear ribonucleoprotein polypeptide N quantitative methylation analysis in infants with central hypotonia.

Central hypotonic is one of the most difficult issues in neurology, ruling out neurogenetic syndromic causes is critical, Prader-Willi syndrome (PWS) it is the most frequent genetic syndrome, it is caused by the loss of expression of the paternal allele in a group of imprinted genes within 15q11-q13, and is characterized by severe prenatal and postnatal hypotonia. SNURF-SNRPN gene methylation detects 99% of the cases but fluorescent in situ hybridization (FISH) analysis is necessary to confirm chromosome microdeletions. The advantage of SNRP-quantitative strategy of methylated alleles is that it makes it possible to make the diagnosis and identify deletions and mosaicism in one reaction. In infants clinical diagnosis is difficult. It has been proposed that around 40% of hypotonic patients have PWS but an accurate percentage has not been established. Twenty-four central hypotonic infants were studied by this molecular strategy, showing 41.5% with the disease. This molecular approach also permitted calculation of gene dosage and detection of those cases with microdeletion.

Hexavalent chromium reduction by bacterial consortia and pure strains from an alkaline industrial effluent.

AIMS: To characterize the bacterial consortia and isolates selected for their role in hexavalent chromium removal by adsorption and reduction. METHODS AND RESULTS: Bacterial consortia from industrial wastes revealed significant Cr(VI) removal after 15 days when incubated in medium M9 at pH 6·5 and 8·0. The results suggested chromium reduction. The bacterial consortia diversity (T-RFLP based on 16S rRNA gene) indicated a highest number of operational taxonomic units in an alkaline carbonate medium mimicking in situ conditions. However, incubations under such conditions revealed low Cr(VI) removal. Genomic libraries were obtained for the consortia exhibiting optimal Cr(VI) removal (M9 medium at pH 6·5 and 8·0). They revealed the dominance of 16S rRNA gene sequences related to the genera Pseudomonas/Stenotrophomonas or Enterobacter/Halomonas, respectively. Isolates related to Pseudomonas fluorescens and Enterobacter aerogenes were efficient in Cr(VI) reduction and adsorption to the biomass. CONCLUSIONS: Cr(VI) reduction was better at neutral pH rather than under in situ conditions (alkaline pH with carbonate). Isolated strains exhibited significant capacity for Cr(VI) reduction and adsorption. SIGNIFICANCE AND IMPACT OF STUDY: Bacterial communities from chromium-contaminated industrial wastes as well as isolates were able to remove Cr(VI). The results suggest a good potential for bioremediation of industrial wastes when optimal conditions are applied.

Behavioral and biochemical effects of neonicotinoid thiamethoxam on the cholinergic system in rats.

Thiamethoxam is a neonicotinoid insecticide, a group of pesticides that acts selectively on insect nicotinic acetylcholine receptors (nAChRs), with only a little action on mammalian nAChRs. Nevertheless, the selectivity of neonicotinoids for the insect nAChRs may change when these substances are metabolized. Therefore, we aimed to determine the potential effects of thiamethoxam on mammalian brain, testing the performance in the open field and elevated plus-maze of rats exposed to this insecticide and, in order to establish the neurochemical endpoints, we measured the acetylcholinesterase activity in different brain regions (hippocampus, striatum and cortex) and the high-affinity choline uptake (HACU) in synaptosomes from rat hippocampus. Treated animals received thiamethoxam (25, 50 or 100mg/kg) for 7 consecutive days. The results showed that treatment with thiamethoxam induced an increase in the anxiety behavior at two doses (50 or 100mg/kg). Moreover, there was a significant decrease in both HACU and acetylcholinesterase activity. Our hypothesis is that thiamethoxam (or its metabolites) could be acting on the central rats nAChRs. This would produce an alteration on the cholinergic transmission, modulating the anxiety behavior, acetylcholinesterase levels and HACU.

Evaluation of the effects and mechanisms of action of flutriafol, a triazole fungicide, on striatal dopamine release by using in vivo microdialysis in freely moving rats.

The purpose of the present work was to assess the effects of flutriafol, a triazole fungicide, on in vivo dopamine (DA) release from rat striatum, using brain microdialysis coupled to high-performance liquid chromatography with electrochemical detection (HPLC-EC). Intrastriatal administration of flutriafol (1, 6 and 12 mM) produced significant concentration-dependent increases in DA levels to 218.5+/-51%, 1376+/-245% and 3093+/-345% compared with basal values, respectively. Those increases in DA levels could be due to an increased DA exocytotic release and/or a change in the activity of DA transporter (DAT). Thus, we investigated the effects of flutriafol (6mM) under Ca(++)- or Na(+)-free conditions, and after pretreatment with reserpine and TTX. When flutriafol was perfused in either Ca(++)- or Na(+)-free Ringer, the DA levels reduced 92% and 70%, respectively; perfusion of flutriafol in TTX-treated (10 microM) or reserpine-pretreated animals (10mg/kg), reduced the levels of DA to 73% and 86%, respectively. Co-infusion of flutriafol and nomifensine (20 microM) shows that the flutriafol-induced DA release did not involve the DAT. Our results suggest that flutriafol induces DA release via vesicular-, Ca(++)-, Na(+)- and TTX-dependent mechanism, being independent of DAT.

MALDI-TOF MS analysis of labile Lolium perenne major allergens in mixes.

BACKGROUND: It is well known that allergen extracts used for specific therapy of allergic disorders are commonly stored as mixtures, causing an alteration of its stability. OBJECTIVE: The aim of this report is to identify pollen allergens susceptible to degradation during storage of mixtures containing different sources of proteases in the absence of glycerol as a preserving agent. METHODS: Mixes containing Lolium perenne (Lol p) pollen extract with either Aspergillus fumigatus or Periplaneta americana extracts were prepared and co-incubated for 90 days at 4 degrees C. Samples were taken off at fixed times and comparatively tested by in vitro and in vivo assays with atopic patients. Selected pollinic allergens were subjected to MALDI-TOF MS analysis. RESULTS: ELISA inhibition evidenced the loss of potency from ryegrass extract, and immunoblotting assays showed the degradation of specific pollinic allergens during storage of mixtures containing protease-rich sources. An in vivo intradermal skin assay confirmed the gradual loss of the biological activity of L. perenne pollen extract co-incubated with non-related protease-rich extracts in comparison with that of the control pollen extract. MALDI-TOF MS analysis allowed us to determine that Lol p 1 and Lol p 5 are susceptible to proteolysis whereas Lol p 4 was found to be resistant to degradation during storage. CONCLUSIONS: Lol p 1 and Lol p 5 degradation is responsible for the loss of the biological activity of L. perenne pollen extract when co-incubated with protease-rich fungal and cockroach extracts in the same vial for months in the absence of glycerol as a preserving agent. The integrity of these major allergens must be preserved to increase the vaccine stability and to assure efficacy when mixes are used for immunotherapy.

Comportamiento sexual y factores biodemográficos asociados a infecciones de transmisión sexual / Sexual behavior and biodemographic factors associated with sexually transmitted infections

OBJETIVO: analizar el comportamiento sexual y factores biodemográficos asociados a infecciones de transmisión sexual. MÉTODOS: estudio caso-control, realizado en el Hospital San José de Coronel Chile, en el año 2007. En una muestra de 100 mujeres, entre 15 y 34 años de edad, 50 usuarias con ITS y 50 sin ITS. Se aplicó un instrumento auto-administrado, para variables socioculturales y de comportamiento sexual, se aplicaron las pruebas de ÷² y ƒ fisher. RESULTADOS: hubo diferencias estadísticamente significativas en las variables edad de inicio de las relaciones sexuales, número de parejas sexuales, uso de preservativo y conocimientos sobre el carácter contagioso de las ITS. Las principales infecciones fueron condilomatosis acuminada (HPV) 52 % y sífilis (25 %). CONCLUSIONES: la conducta sexual de riesgo y la escasa información sobre el contagio son factores asociados a las infecciones de transmisión sexual.

OBJECTIVE: to analyze the sexual behavior and biodemography factors associated with sexually transmitted infections (STIs). METHODS: case-control study conducted at the San Jose de Coronel Hospital, Chile, in 2007. In a sample of 100 women between 15 and 34 years old, 50 with STIs and 50 without STIs, a self-administered instrument was applied for sociocultural and sexual behaviour variables. The ?2 and Fisher's tests were used. RESULTS: there were statistically significant differences at the age of initiating sexual relations, the number of sexual partners, the use of condom, and the knowledge about the contagious nature of STIs. Major infections were acuminated condyloma (HPV) 52% and syphilis (25%). CONCLUSIONS: the risk sexual behavior and the poor information about the infection are factors associated with sexually transmitted infections.

The use of PDAs to collect baseline survey data: lessons learned from a pilot project in Bolivia.

We compared the use of personal digital assistants (PDAs) against the use of standard paper questionnaires for collecting survey data. The evaluation consisted of qualitative approaches to document the process of introducing PDAs. Fieldwork was carried out during June-July 2005 at 12 sites in Bolivia. Data collectors reacted positively to the use of the PDAs and noted the advantages and disadvantages of paper and PDA data collection. A number of difficulties encountered in the use of PDA technology serve as a warning for investigators planning its adoption. Problems included incompatible data files (which impeded the ability to interpret data), an inadequate back-up protocol, and lack of a good 'fit' between the technology and the study. Ensuring the existence of a back-end database, developing an appropriate and adequate back-up protocol, and assessing whether a technology 'fits' the project are important factors in weighing the decision to collect data using PDAs.

Proteomic analysis of metacyclic trypomastigotes undergoing Trypanosoma cruzi metacyclogenesis.

Trypanosoma cruzi, the causative agent of the Chagas disease, has a complex life cycle alternating between replicative and noninfective forms with nonreplicative and infective forms of the parasite. Metacyclogenesis is a process that takes place in the invertebrate host, comprising morphogenetic transformation from a noninfective form to an infective form, such that parasites acquire the ability to invade human cells. We analyze here the metacyclogenesis process by 2D electrophoresis coupled to MALDI-TOF MS. A large proportion of unique proteins expressed during metacyclogenesis were observed. Interestingly, 50% of the spots were found to differ between epimastigotes and trypomastigotes. We provide a 2D map of the infective metacyclic trypomastigotes. Sixty six protein spots were successfully identified corresponding to 43 different proteins. We analyzed the expression profiles for the identified proteins along metacyclogenesis and classified them into three groups according to their maximal level of expression. We detected several isoforms for a number of proteins, some displaying differential expression during metacyclogenesis. These results suggest that posttranslational modifications may be a fundamental part of the parasite's strategy for regulating gene expression during differentiation. This study contributes to the identification of relevant proteins involved in the metacyclogenesis process. The identification and molecular characterization of these proteins will render vital information about the steps of the parasite differentiation into the infective form.

Comparative effects of organic and inorganic mercury on in vivo dopamine release in freely moving rats

The present study was carried out in order to compare the effects of administration of organic (methylmercury, MeHg) and inorganic (mercury chloride, HgCl 2 ) forms of mercury on in vivo dopamine (DA) release from rat striatum. Experiments were performed in conscious and freely moving female adult Sprague-Dawley (230-280 g) rats using brain microdialysis coupled to HPLC with electrochemical detection. Perfusion of different concentrations of MeHg or HgCl 2 (2 muL/min for 1 h, N = 5-7/group) into the striatum produced significant increases in the levels of DA. Infusion of 40 muM, 400 muM, or 4 mM MeHg increased DA levels to 907 ± 31, 2324 ± 156, and 9032 ± 70 percent of basal levels, respectively. The same concentrations of HgCl 2 increased DA levels to 1240 ± 66, 2500 ± 424, and 2658 ± 337 percent of basal levels, respectively. These increases were associated with significant decreases in levels of dihydroxyphenylacetic acid and homovallinic acid. Intrastriatal administration of MeHg induced a sharp concentration-dependent increase in DA levels with a peak 30 min after injection, whereas HgCl 2 induced a gradual, lower (for 4 mM) and delayed increase in DA levels (75 min after the beginning of perfusion). Comparing the neurochemical profile of the two mercury derivatives to induce increases in DA levels, we observed that the time-course of these increases induced by both mercurials was different and the effect produced by HgCl 2 was not concentration-dependent (the effect was the same for the concentrations of 400 muM and 4 mM HgCl 2 ). These results indicate that HgCl 2 produces increases in extracellular DA levels by a mechanism differing from that of MeHg.

Comparative effects of organic and inorganic mercury on in vivo dopamine release in freely moving rats.

The present study was carried out in order to compare the effects of administration of organic (methylmercury, MeHg) and inorganic (mercury chloride, HgCl 2 ) forms of mercury on in vivo dopamine (DA) release from rat striatum. Experiments were performed in conscious and freely moving female adult Sprague-Dawley (230-280 g) rats using brain microdialysis coupled to HPLC with electrochemical detection. Perfusion of different concentrations of MeHg or HgCl 2 (2 microL/min for 1 h, N = 5-7/group) into the striatum produced significant increases in the levels of DA. Infusion of 40 microM, 400 microM, or 4 mM MeHg increased DA levels to 907 +/- 31, 2324 +/- 156, and 9032 +/- 70% of basal levels, respectively. The same concentrations of HgCl 2 increased DA levels to 1240 +/- 66, 2500 +/- 424, and 2658 +/- 337% of basal levels, respectively. These increases were associated with significant decreases in levels of dihydroxyphenylacetic acid and homovallinic acid. Intrastriatal administration of MeHg induced a sharp concentration-dependent increase in DA levels with a peak 30 min after injection, whereas HgCl 2 induced a gradual, lower (for 4 mM) and delayed increase in DA levels (75 min after the beginning of perfusion). Comparing the neurochemical profile of the two mercury derivatives to induce increases in DA levels, we observed that the time-course of these increases induced by both mercurials was different and the effect produced by HgCl 2 was not concentration-dependent (the effect was the same for the concentrations of 400 microM and 4 mM HgCl 2 ). These results indicate that HgCl 2 produces increases in extracellular DA levels by a mechanism differing from that of MeHg.

Analysis of the Trypanosoma cruzi cyclophilin gene family and identification of Cyclosporin A binding proteins.

The Trypanosoma cruzi cyclophilin gene family comprises 15 paralogues whose nominal masses vary from 19 to 110 kDa, namely TcCyP19, TcCyP20, TcCyP21, TcCyP22, TcCyP24, TcCyP25, TcCyP26, TcCyP28, TcCyP29, TcCyP30, TcCyP34, TcCyP35, TcCyP40, TcCyP42 and TcCyP110. Under the conditions used, only some of the T. cruzi cyclophilin paralogue products could be isolated by affinity chromatography. The 15 paralogues were aligned with 495 cyclophilins from diverse organisms. Analyses of clusters formed by the T. cruzi cyclophilins with others encoded in various genomes revealed that 8 of them (TcCyP19, TcCyP21, TcCyP22, TcCyP24, TcCyP35, TcCyP40, TcCyP42 and TcCyP110) have orthologues in many different genomes whereas the other 7 display less-defined patterns of their sequence attributes and their classification to a specific group of cyclophilin's orthologues remains uncertain. Seven epimastigote cDNA clones encoding cyclophilin isoforms were further studied. These genes were found dispersed throughout the genome of the parasite. Amastigote and trypomastigote mRNAs encoding these 7 genes were also detected. We isolated 4 cyclosporin A-binding proteins in T. cruzi epimastigote extracts, which were identified by mass spectrometry as TcCyP19, TcCyP22, TcCyP28 and TcCyP40. Cyclosporin A-binding to these cyclophilins might be of importance to the mechanism of action of Cyclosporin A and its non-immunosuppressive analogues, whose trypanocidal effects were previously reported, and therefore, of potential interest in the chemotherapy of Chagas' disease.