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1.
Actas Dermosifiliogr ; 113(7): 705-711, 2022.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35288099

RESUMO

Vitiligo is a pigmentary disorder, in which oxidative stress has been evidenced as part of the pathogenesis. Pathways responsible for protecting melanocytes from damage caused by reactive oxygen species are known as the nuclear factor erythroid factor 2 (Nrf2) pathway. Nrf2 is a transcription factor that remains inhibited when the organism is in homeostasis, but in the presence of oxidative stress it allows the encoding of phase ii antioxidant enzymes. In vitiligo there are abnormalities in the location and function of Nrf2 as well as polymorphisms that increase the risk of this disease. Currently, multiple molecules that act on Nrf2 have been investigated in order to find useful emerging treatments for vitiligo. A search for articles in Spanish and English was carried out in the PubMed, Ovid, Scopus and Web of Science Clarivate databases, using the keywords "Vitiligo AND nuclear factor erythroid derived 2 like 2 OR NRF2" without time restriction. All in vitro studies, narrative reviews, case series, cohort studies, and randomized and non-randomized clinical trials that specifically addressed the issue of Nrf2 associated with vitiligo were included.


Assuntos
Hipopigmentação , Vitiligo , Humanos , Melanócitos/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/uso terapêutico , Estresse Oxidativo , Vitiligo/tratamento farmacológico
2.
Ecotoxicol Environ Saf ; 201: 110821, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32544746

RESUMO

Primary production (PP) is a key variable to evaluate the quality of the ecological services provided by freshwater bodies because it gives information on the amount of oxygen and organic matter incorporated into the system. We analysed the impact of a mixture of commercial formulations of glyphosate- and 2,4-D-based herbicides (Roundup Max® and AsiMax 50®, respectively) on freshwater primary production. Primary production was studied through the oxygen exchange method. Four measurements were made during a 23-day experiment in outdoor mesocosms using the light and dark bottle method. High and low concentrations of the active ingredients were assayed to evaluate a concentration-dependent effect. Our results indicated that the mixture of Roundup Max® and AsiMax 50® acted mostly additively on gross and net primary production. Moreover, we found a concentration-dependent effect of each herbicide on PP. Thus, AsiMax 50® at low and Roundup Max® at high concentration induced a significant early decrease in respiration and gross primary production 4 h after application, attributable to physiological responses. Besides, significant increases in primary production were simultaneously recorded with increases in chlorophyll a concentration and micro + nano-phytoplankton abundance 7 days after the application of Roundup Max® at high concentration. This study contributes to the knowledge of the impact of widely used herbicides on freshwater ecosystems.


Assuntos
Água Doce/química , Herbicidas/toxicidade , Microbiota/efeitos dos fármacos , Fitoplâncton/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Ácido 2,4-Diclorofenoxiacético/análise , Ácido 2,4-Diclorofenoxiacético/toxicidade , Animais , Clorofila A/metabolismo , Relação Dose-Resposta a Droga , Água Doce/análise , Glicina/análogos & derivados , Glicina/análise , Glicina/toxicidade , Herbicidas/análise , Fitoplâncton/metabolismo , Poluentes Químicos da Água/análise , Glifosato
3.
Sci Total Environ ; 942: 173685, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38825192

RESUMO

Pesticide mixtures are frequently utilized in agriculture, yet their cumulative effects on aquatic organisms remain poorly understood. Aquatic animals can be effective bioindicators and invasive bivalves, owing to their widespread distribution, provide an opportunity to assess these impacts. Glyphosate and imidacloprid, among the most prevalent pesticides globally, are frequently detected in freshwater systems in South America. This study aims to understand the cumulative effects of pesticide mixtures on aquatic organisms, using invasive Corbicula largillierti clams from a natural stream in northwestern Argentina. We conducted 48-hour exposure experiments using two concentrations of imidacloprid (20 and 200 µg L-1 a.i), two concentrations of glyphosate (0.3 and 3 mg L-1 a.i), and two combinations of these pesticides (both at low and high concentrations, respectively), simulating the direct contamination of both pesticides based on their agronomic recipe and observed values in Argentine aquatic environments. Clam metabolism was assessed through the examination of multiple oxidative stress parameters and measuring oxygen consumption rate as a proxy for standard metabolic rate (SMR). Our findings revealed that imidacloprid has a more pronounced effect compared to glyphosate. Imidacloprid significantly decreased clam SMR and cellular levels of reduced glutathione (GSH). However, when both pesticides were present, also cellular glycogen and thiobarbituric acid-reactive substances (TBARS) were affected. Proteins and glutathione S-Transferase (GST) activity were unaffected by either pesticide or their mixture at the assayed concentrations, highlighting the need to test several stress parameters to detect toxicological impacts. Our results indicated additive effects of imidacloprid and glyphosate across all measured parameters. The combination of multiple physiological and cytological biomarkers in invasive bivalves offers significant potential to enhance biomonitoring sensitivity and obtain insights into the origins and cellular mechanisms of chemical impacts. These studies can improve pollution regulatory policies and pesticide management.


Assuntos
Biomarcadores , Corbicula , Glicina , Glifosato , Neonicotinoides , Nitrocompostos , Poluentes Químicos da Água , Neonicotinoides/toxicidade , Animais , Nitrocompostos/toxicidade , Poluentes Químicos da Água/toxicidade , Glicina/análogos & derivados , Glicina/toxicidade , Biomarcadores/metabolismo , Argentina , Corbicula/efeitos dos fármacos , Herbicidas/toxicidade , Monitoramento Ambiental , Estresse Oxidativo/efeitos dos fármacos , Inseticidas/toxicidade
4.
Rev Esp Quimioter ; 34(6): 639-650, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34806858

RESUMO

OBJECTIVE: Carbapenem-resistant Gram-negative (CRGN) infections are a major public health problem in Spain, often implicated in complicated, healthcare-associated infections that require the use of potentially toxic antibacterial agents of last resort. The objective of this study was to assess the clinical management of complicated infections caused by CRGN bacteria in Spanish hospitals. METHODS: The study included: 1) a survey assessing the GN infection and antibacterial susceptibility profile in five participating Spanish hospitals and 2) a non-interventional, retrospective single cohort chart review of 100 patients with complicated urinary tract infection (cUTI), complicated intra-abdominal infection (cIAI), or hospital-acquired bacterial pneumonia/ventilator-associated bacterial pneumonia (HABP/VABP) attributable to CRGN pathogens. RESULTS: In the participating hospitals CRGN prevalence was 9.3% amongst complicated infections. In the retrospective cohort, 92% of infections were healthcare-associated, and Klebsiella pneumoniae and Pseudomonas aeruginosa were the most common pathogens. OXA was the most frequently detected carbapenemase type (71.4%). We found that carbapenems were frequently used to treat cUTI, cIAI, HABP/VABP caused by CRGN pathogens. Carbapenem use, particularly in combination with other agents, persisted after confirmation of carbapenem resistance. Clinical cure was 66.0%, mortality during hospitalization 35.0%, mortality at the time of chart review 62.0%, and 6-months-post-discharge readmission 47.7%. CONCLUSIONS: Our results reflect the high burden and unmet needs associated with the management of complicated infections attributable to CRGN pathogens in Spain and highlight the urgent need for enhanced clinical management of these difficult-to-treat infections.


Assuntos
Infecções por Bactérias Gram-Negativas , Infecções Intra-Abdominais , Pneumonia Bacteriana , Infecções Urinárias , Assistência ao Convalescente , Antibacterianos/uso terapêutico , Carbapenêmicos/uso terapêutico , Bactérias Gram-Negativas , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/epidemiologia , Humanos , Infecções Intra-Abdominais/tratamento farmacológico , Alta do Paciente , Pneumonia Bacteriana/tratamento farmacológico , Estudos Retrospectivos , Espanha/epidemiologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/epidemiologia , Ventiladores Mecânicos
5.
Rev Esp Quimioter ; 34(2): 126-135, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33618513

RESUMO

OBJECTIVE: Clostridioides difficile infection (CDI) is associated with increased hospital stays and mortality and a high likelihood of rehospitalization, leading to increased health resource use and costs. The objective was to estimate the economic burden of recurrent CDI (rCDI). METHODS: Observational, retrospective study carried out in six hospitals. Adults aged ≥18 years with ≥1 confirmed diagnosis (primary or secondary) of rCDI between January 2010 and May 2018 were included. rCDI-related resource use included days of hospital stay (emergency room, ward, isolation and ICU), tests and treatments. For patients with primary diagnosis of rCDI, the complete hospital stay was attributed to rCDI. When diagnosis of rCDI was secondary, hospital stay attributed to rCDI was estimated using 1:1 propensity score matching as the difference in hospital stay compared to controls. Controls were hospitalizations without CDI recorded in the Spanish National Hospital Discharge Database. The cost was calculated by multiplying the natural resource units by the unit cost. Costs (euros) were updated to 2019. RESULTS: We included 282 rCDI episodes (188 as primary diagnosis): 66.31% of patients were aged ≥65 years and 57.80% were female. The mean hospital stay (SD) was 17.18 (23.27) days: 86.17% of rCDI episodes were isolated for a mean (SD) of 10.30 (9.97) days. The total mean cost (95%-CI) per episode was €10,877 (9,499-12,777), of which the hospital stay accounted for 92.56. CONCLUSIONS: There is high cost and resource use associated with rCDI, highlighting the importance of preventing rCDI to the Spanish National Health System.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Adolescente , Adulto , Clostridioides , Infecções por Clostridium/epidemiologia , Efeitos Psicossociais da Doença , Feminino , Hospitalização , Hospitais , Humanos , Recidiva Local de Neoplasia , Recidiva , Estudos Retrospectivos
6.
Heliyon ; 5(8): e02221, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31463387

RESUMO

We evaluated the effect of AsiMax 50®, a commercial formulation of 2,4-D (2,4-dichlorophenoxyacetic acid), on the structure of both micro + nano phytoplankton (>2 µm; species composition and abundance) and cytometric populations (photosynthetic picoplankton (PPP, 0.2-2 µm), which included prokaryotic phycocyanin-rich picocyanobacteria (PC-Pcy), phycoerythrin-rich picocyanobacteria (PE-Pcy) and eukaryotic phototrophs (PEuk); and bacterioplankton (HB), heterotrophic bacteria), using a microcosms-based approach and a single 7-day exposure. Assays were performed on two different microbial assemblages sampled from freshwater bodies of two contrasting turbidity status: clear (chlorophyll a = 7.6 µgL-1, turbidity = 1 NTU) and organic turbid systems (chlorophyll a = 25.0 µgL-1, turbidity = 9 NTU). For each system, the herbicide was applied to 500 mL-Erlenmeyer flasks, at seven concentration levels of the active ingredient (a.i.): 0 (control = no addition), 0.02, 0.2, 2, 20, 200 and 2,000 mg a.i.L-1. The impact of AsiMax 50® seemed to be greater in the turbid system. In this system, total abundance of living (live) micro + nano phytoplankton showed a significant increase at lower concentrations and data were fitted to a humped-shaped curve. For both clear and organic turbid systems, micro + nano phytoplankton decreased in species richness and abundance at higher herbicide concentrations. These results suggest that 2,4-D may mimic hormonal function. Some species, such as Ochromonas sp. and Chlamydomonas sp., showed different responses to herbicide exposure between water systems. In the turbid system, the increase in abundance of the PPP fraction observed at 7-d exposure was probably due to either an increase in PE-Pcy (thus suggesting the existence of auxin pathways) or a reduction in competitive pressure by micro + nano plankton. Our results provide some evidence of the importance of using community-scale approaches in ecotoxicological studies to predict changes in freshwater ecosystems exposed to a 2,4-D-based formulation. However, caution must be taken when extrapolating these effects to real scenarios, as assays were based on a laboratory microcosm experiment.

7.
Parasitology ; 135(14): 1651-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18980700

RESUMO

Neospora caninum is a cyst-forming parasite that causes abortion in cattle. Despite this parasite's ubiquitous distribution and wide host range, the number of N. caninum isolates obtained to date is limited. In vitro isolation of the parasite is arduous and often unsuccessful. In addition, most isolates have been obtained from clinically affected hosts and therefore could be biased towards more virulent isolates. In this report, an improved isolation approach from transplacentally infected newborn calves was undertaken and 9 new isolates were obtained. Moreover, a microsatellite technique was applied to investigate the genetic diversity of these isolates. Most isolates showed specific genetic profiles. However, the Nc-Spain10 isolate was identical to the previously described Nc-Spain1H isolate and Nc-Spain3H was identical to Nc-Spain4H. These isolates were likely to have identical genotypes because they were isolated from distinct calves of the same herd. Future pathogenic characterization of these isolates will contribute to the investigation of the relationship between isolate virulence and the outcome of infection, as well as other epidemiological features, such as transmission.


Assuntos
Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Variação Genética , Neospora/genética , Alelos , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio , Bovinos , Células Cultivadas , Coccidiose/parasitologia , Feminino , Genótipo , Masculino , Camundongos , Camundongos Nus , Repetições de Microssatélites/genética , Neospora/classificação , Neospora/isolamento & purificação , Espanha , Especificidade da Espécie
8.
Vet Parasitol ; 157(3-4): 182-95, 2008 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-18814972

RESUMO

Bovine reproductive failure caused by the parasite Neospora caninum is a major problem and is responsible for severe economic losses worldwide. Currently, appropriate control measures depend on the predominant transmission route in a particular herd. Therefore, the development of diagnostic tools capable of discriminating between primo-infection, recrudescence, re-infection, and chronic infection is a major challenge in the serodiagnosis of bovine neosporosis. Here, two recombinant protein-based ELISAs utilizing the immunodominant NcGRA7 dense granule protein and the NcSAG4 bradyzoite stage-specific protein were developed and showed good diagnostic performances. Their usefulness for discerning between primo-infection, recrudescence, re-infection, and chronic infection was also studied by analyzing an appropriate panel of serum samples belonging to different groups of experimentally and naturally infected bovines. Our results suggest that anti-rNcGRA7 antibody levels may be indicative of acute infection (primo-infection, re-infection, and recrudescence), whereas the presence of anti-rNcSAG4 antibodies may be associated with chronic infection and could be a good indicator of infection establishment (tachyzoite-bradyzoite conversion). Moreover, primo-infection associated with a Neospora-associated epidemic abortion pattern is characterized by the detection of anti-rNcGRA7 antibodies together with the absence or detection of anti-rNcSAG4 antibody levels around the cut-off point. In contrast, the detection of antibody levels directed against both recombinant proteins may be quite indicative of recrudescence or re-infection associated with abortion and/or vertical transmission in herds with a Neospora-associated endemic abortion pattern. In conclusion, both serological tests developed in the present study offer additional information to conventional avidity tests and, consequently, improve the diagnosis of bovine neosporosis with perspectives for control measures.


Assuntos
Doenças dos Bovinos/diagnóstico , Coccidiose/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Neospora , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/patologia , Doença Crônica , Coccidiose/diagnóstico , Coccidiose/parasitologia , Coccidiose/patologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Masculino , Recidiva
9.
Water Sci Technol ; 58(7): 1415-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18957754

RESUMO

This study attempted to investigate the impact of HRT of treated leachate recirculation on hydrolysis solubilization rate of coffee pulp in an acidogenic reactor. Coffee pulp presents more than 70% of organic matter and around of 30% of lignin and cellulose. Five lab scale reactors of 20 litres were used. Each reactor was fed with 5 kg of fresh coffee pulp and anaerobic sludge was used as inoculate. HRT of 0.5, 1, 3 and 10 days were applied. Each experiment shows that Total, Soluble and VFA COD appear rapidly in the removed leachate. HRT have a great impact on hydrolytic rate with an optimal value of 32,000 mg x L(-1) x d(-1).Low HRT increases hydrolysis rate and in consequence reduces duration of the hydrolytic phase. Also composition and concentration of VFA are influenced by HRT. Low ones favour acetic acid production and high ones permit the production of butyric. Low HRT generates leachate more easily fermentable. Efficiency of solubilization and acidification are independent of the HRT and present average values of 78% and 65% respectively. By batch feeding solid and continuous recirculation of treated leachate, HRT and SRT could be dissociated, where solid had a very high retention without problems of load, mixing and inhibition, and liquid could be recirculated with a very high rate. Under these low HRT condition, the first reactor of a two stage anaerobic system could reduces the hydrolysis duration of organic solid waste like coffee pulp and generate an optimal leachate for the methanization process.


Assuntos
Café/química , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Celulose/química , Celulose/metabolismo , Café/metabolismo , Hidrólise , Cinética , Lignina/química , Lignina/metabolismo , Esgotos/química , Esgotos/microbiologia , Solubilidade
10.
Rev. Asoc. Colomb. Cien. Biol. (En línea) ; 2(33): 102-112, 2021. tab, graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1379310

RESUMO

Introducción: En la región Caribe de Colombia hay presencia de especies nativas de gramíneas que aún no han sido evaluadas. Objetivo: Identificar taxonómicamente una gramínea de la región Sabanas de Sucre y estudiar la influencia de la edad sobre sus atributos morfológicos y de producción. Materiales y métodos: El estudio se ubicó en 9º12'38.59" N y 75º24'06.63", a 165 msnm. En 18 parcelas se evaluaron tres intervalos de corte (21, 28 y 35 días). Inicialmente, se identificó la gramínea. Fue evaluada la composición química, el número y longitud de las hojas, las relaciones entre material verde y seco y entre hojas y tallos, y su evolución, y la producción y tasa de acúmulo de MS. Resultados: La gramínea se identificó como Panicum cf. hispidifolium Swallen. El contenido de PB, NDT y cenizas disminuyeron (P<0,05) con el incremento en la edad, presentando valores medios de 12,3; 58,5 y 9,7%, respectivamente. Las fracciones MS, FDA y CNE aumentaron (P<0,05) con la edad, presentando valores medios de 21,6; 37,17 y 6,24%, respectivamente. La disponibilidad de MS y la tasa de acúmulo evolucionaron cuadráticamente (P<0,05), con mayor intensidad entre los días 21 y 28. El promedio de MS disponible fue de 8049,1 kg/ha y la tasa diaria de acúmulo fue de 281,2 kg/ha. Conclusión: Se concluye que P. hispidifolium es una gramínea con potencial forrajero para la región Sabanas de Sucre, y que se debe manejar con periodos de descanso de alrededor de 28 días, considerando la disponibilidad y calidad de la MS.


Introduction: In the Caribbean region of Colombia there are native species of grasses that have not yet been evaluated. Objective: To identify taxonomically a grass observed in the Savannas de Sucre region and study the influence of age on its morphological and production attributes. Materials and Methods: The study was located at 9º12'38.59"N and 75º24'06.63", at 165 meters above sea level. In 18 plots, three cut intervals were evaluated (21, 28 and 35 days). Initially, the grass was identified. The chemical composition, the number and length of the leaves, the relationships between green and dry material and between leaves and stems, and their evolution, and the production and accumulation rate of DM were tested. Results: The grass was identified as Panicum cf. hispidifolium Swallen. The content of PB, NDT and ash decreased (P <0.05) with increasing age, presenting mean values of 12.27; 58.5 and 9.7%, respectively. The MS, FDA and CNE fractions increased (P <0.05) with age, presenting mean values of 21.6; 37.17 and 6.24%, respectively. DM availability and accumulation rate evolved quadratically (P <0.05), with greater intensity between days 21 and 28. The average DM available was 8049.1 kg / ha and the daily accumulation rate was 281.2 kg / ha. Conclusion: It is concluded that P. hispidifolium is a grass with forage potential for the Savannas of Sucre region, and that it should be managed with rest periods of around 28 days, considering the availability and quality of the DM.


Assuntos
Panicum , Colômbia , Vernonia
11.
J Parasitol ; 91(3): 507-10, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16108539

RESUMO

Neospora caninum, a recently recognized protozoan parasite of animals, is considered to be a major cause of bovine abortion worldwide. Although its life cycle is not completely known, recent studies suggest that the sexual stage occurs in dogs. The prevalence of sexual reproduction in N. caninum, however, is unknown. We investigated the ability of 3 N. caninum isolates (NC-1, NC-SweB1, and NC-Liverpool) to propagate asexually for approximately 250 parasite generations in a cell line in which they had not been cultured previously. The malthusian parameter of fitness was estimated for each isolate from 10 independent replicates of tachyzoites at the beginning as well as at the end of the experimental period. Derived and ancestral values for mean fitness were compared both within and among NC-1, NC-SweB1, and NC-Liverpool isolates. Results showed a significant increase in mean fitness for the 3 N. caninum isolates at the end of the experimental period. These findings indicate that N. caninum can adapt to new environmental conditions without the help of sexual recombination, supporting the idea that this parasite has, at least potentially, the capacity for maintaining clonal propagation in nature.


Assuntos
Adaptação Fisiológica , Neospora/fisiologia , Reprodução Assexuada/fisiologia , Animais , Chlorocebus aethiops , Técnicas de Cultura/métodos , Neospora/crescimento & desenvolvimento , Inoculações Seriadas/veterinária , Células Vero
12.
Arch Soc Esp Oftalmol ; 80(12): 719-24, 2005 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-16372215

RESUMO

PURPOSE: Luminance (L) and area (A) of the stimulus are related by the equation LxAk=constant. We evaluated the k value in 66 positions of the central visual field. METHODS: Ten eyes of 10 healthy subjects were examined for conventional luminous thresholds at 66 positions of the central visual field with the TOP strategy using Goldmann sizes 4, 3.5, 3, 2.5 and 1.9 in the PULSAR perimeter. RESULTS: The k value increased in a lineal manner from the centre towards the periphery (slope=0.01 per degree, average k=0.616, r=0.98, p<0.01) but with unequal slopes at the different meridians. In the inferior hemi-fields it was higher (k=0.657) than in the superior hemi-fields (k=0.574). The k value at the supero-nasal hemifields is quite similar to that found at the paracentral region, and maximum at the temporal inferior region. CONCLUSIONS: Spatial summation in the central visual field has specific values for different positions.


Assuntos
Percepção Espacial/fisiologia , Campos Visuais/fisiologia , Feminino , Fóvea Central/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Transtornos da Visão/fisiopatologia , Testes de Campo Visual
13.
Ann Thorac Surg ; 71(4): 1351-3, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11308191

RESUMO

We present the case of a 53-year-old woman with a history of breast cancer, chemotherapy, and a long-term central venous access catheter, who presented with acute, severe superior vena cava syndrome. Angiography showed fibrous obstruction of the superior vena cava with thrombosis of the innominate, both axillary subclavian and internal jugular veins. Surgical repair consisted of thrombectomy of all the involved vessels and patch repair of superior vena cava and innominate vein. The patient had an uneventful recovery and remains asymptomatic 12 months after the procedure.


Assuntos
Síndrome da Veia Cava Superior/cirurgia , Angiografia/métodos , Antineoplásicos/administração & dosagem , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Cateterismo Venoso Central/efeitos adversos , Cateterismo Venoso Central/métodos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Síndrome da Veia Cava Superior/diagnóstico , Síndrome da Veia Cava Superior/etiologia , Trombectomia/métodos , Resultado do Tratamento , Ultrassonografia Doppler , Procedimentos Cirúrgicos Vasculares/métodos
14.
Behav Brain Res ; 81(1-2): 215-22, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8950019

RESUMO

Mecamylamine, a nicotinic receptor antagonist, was injected into the honeybee brain haemolymph. The effects of the drug were investigated on Pavlovian conditioning of the proboscis extension reflex. The conditioned response was acquired after a one-trial learning session, consisting of an olfactory-conditioned stimulus combined with a gustatory antennal unconditioned stimulus. The drug was injected at different times before or after the learning session in order to dissociate its effects on acquisition, consolidation and retrieval processes. The performance was evaluated in short-delayed recall tasks. To control potential effects on sensory-motor activity, the effects of the drug were also investigated on sensory processes (through olfactory and gustatory functions) and on motor processes of proboscis extension. The results of conditioning experiments showed that pretrial injection induced a decrease of retention performance 1 h after the learning trial. Mecamylamine injected 20 min after the learning session induced a time-dependent impairment of retention performance, as has been shown by the performance level registered from 10 to 80 min after injection. A 5-min post-trial injection had no effect on retention performance. Control experiments did not reveal any effect of mecamylamine on the response reflex of proboscis extension and on responsiveness to olfactory stimuli (geraniol, lavender and vanillin). The absence of effects on sensory perception combined with the amnestic effect induced by pre- or late post-trial injections lead us to conclude that mecamylamine specially impaired acquisition and retrieval processes. The involvement of nicotinic-like receptors in these processes is discussed.


Assuntos
Abelhas/fisiologia , Condicionamento Clássico/efeitos dos fármacos , Mecamilamina/farmacologia , Memória/efeitos dos fármacos , Antagonistas Nicotínicos/farmacologia , Olfato/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/fisiologia , Injeções , Iluminação , Mecamilamina/administração & dosagem , Antagonistas Nicotínicos/administração & dosagem , Órgãos dos Sentidos/fisiologia , Paladar/efeitos dos fármacos
15.
Behav Brain Res ; 63(2): 145-9, 1994 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-7999297

RESUMO

The role of the cholinergic system on learning abilities and memory performance has been investigated in the honeybee. The behavioural experiment was the olfactory conditioning of the proboscis extension reflex, elicited by an antennal sucrose stimulation. Intracranial scopolamine (0.5 mg/kg) or saline injections (0.25 microliter) were given at different times before or after a one trial learning session in order to interfere with acquisition of information, storage or recall processes. Neither scopolamine injections, ranging from 20 min to 5 min prior to the acquisition task, nor post-trial drug injections given in the same time-window, impaired the retention performance measured one hour after conditioning. Scopolamine injected 20 min after a learning session induced a time-dependent decrease of information retrieval, as was seen in retention testing performed from 5 min to one hour after injection. Then, the amnestic effect of intracranial scopolamine injection seems to be related to a specific and temporary inhibition of recall processes. We can conclude that, in the present task, muscarinic-like receptors are involved in information retrieval but not in acquisition or consolidation processes.


Assuntos
Abelhas/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Rememoração Mental/efeitos dos fármacos , Escopolamina/farmacologia , Olfato/efeitos dos fármacos , Animais , Comportamento Apetitivo/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Injeções , Receptores Colinérgicos/efeitos dos fármacos , Receptores Muscarínicos/efeitos dos fármacos , Retenção Psicológica/efeitos dos fármacos
16.
Pharmacol Biochem Behav ; 59(4): 903-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9586847

RESUMO

One-trial conditioning of the proboscis extension reflex (PER) in honeybees was used to examine the qualitative effects of two muscarinic antagonists, atropine and pirenzepine, on the acquisition and retrieval of memory following intracranial injection. The main result of this study is that atropine, at a relatively high concentration of 10(-2) M, impairs memory retrieval but not acquisition of memory after a single olfactory conditioning trial (at this concentration, there is no effect of atropine on the sensorimotor components of the PER). This result is in agreement with the effects of scopolamine, reported in a previously published article. Pirenzepine, at the same concentration as atropine, had no effect on either acquisition or retrieval of memory. These results suggest that blockade of muscarinic-like receptors, except those that bind to pirenzepine, induces solely an impairment of memory retrieval.


Assuntos
Atropina/farmacologia , Abelhas/fisiologia , Condicionamento Clássico/efeitos dos fármacos , Antagonistas Muscarínicos/farmacologia , Pirenzepina/farmacologia , Olfato/efeitos dos fármacos , Animais , Atropina/administração & dosagem , Encéfalo , Injeções , Antagonistas Muscarínicos/administração & dosagem , Pirenzepina/administração & dosagem , Reflexo/efeitos dos fármacos
17.
Biocell ; 20(3): 273-4, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9091099

RESUMO

A staining device for sectioned material supported on grids for viewing at the Transmission Electron Microscope is described. The method based in a double side sticky tape is inexpensive, rapid and clean. By using only pipettes and a double side sticky tape the best solution to the tedious problems of sections staining is obtained. The tape is discarded and the staining solution too. Precipitates have not been observed.


Assuntos
Microscopia Eletrônica/métodos , Coloração e Rotulagem/métodos , Coloração e Rotulagem/economia
18.
Rev Esp Cardiol ; 54(12): 1385-93, 2001 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-11754807

RESUMO

INTRODUCTION AND OBJECTIVES: The asynchronic contraction of the left ventricle due to left bundle branch block or right ventricular pacing is inferior from a hemodynamic point of view to the synchronic contraction through the conduction system. Several authors have reported some cases of pump failure and deterioration of mitral regurgitation after AV nodal ablation. Alternative sites of pacing such as the right ventricular outflow tract pacing have been proposed in order to avoid these complications. Direct His bundle pacing might be a new alternative for permanent pacing, however, it has not been extensively evaluated in humans yet. Our aim is to prove the feasibility of permanent His pacing in terms of stability, thresholds and pump function. POPULATION: patients without structural heart disease, selected for AV nodal ablation due to uncontrolled paroxysmal atrial fibrillation, or for pacemaker implantation due to supraHis conduction disturbance, with normal conduction system. An active fixation permanent lead was placed in His position using an steering guidewire and a diagnostic catheter as an anatomical reference. We also implanted a lead in the right atrial appendage and both were connected to a DDDR generator. Pacing thresholds and ecocardiographic ventricular function parameters were evaluated (ejection fraction, cavity size, mitral regurgitation). RESULTS: 12 patients met the inclusion criteria. Successful His pacing was achieved in 8 out of 12 cases (66%) with acceptable thresholds at implantation (1.24 +/- 0.13 volts at 0.5 ms) and during follow up at 3 months (1.31 +/- 0.20 volts at 0.5 ms). Neither a significant change in the ecocardiographic parameters not a deterioration in the clinical status caused by ablation or stimulation was evidenced. CONCLUSION: The His bundle may be the site of choice for long term pacing in patients with AV block and normal infraHis conduction system.


Assuntos
Fibrilação Atrial/cirurgia , Nó Atrioventricular/cirurgia , Fascículo Atrioventricular , Ablação por Cateter , Desfibriladores Implantáveis , Estimulação Elétrica , Estudos de Viabilidade , Humanos
19.
Rev Laryngol Otol Rhinol (Bord) ; 111(4): 401-6, 1990.
Artigo em Francês | MEDLINE | ID: mdl-2281227

RESUMO

Disorders associated with swallowing often appear with difficulty in swallowing or with a cough when food goes down the wrong way. However, a detailed analysis of such disorders shows some distinctive characteristics based on neurological or surgical etiologies. Identification of the physiopathological mechanisms of the different types of deglutition allows for the elaboration of the appropriate rehabilitation strategies.


Assuntos
Nervos Cranianos/fisiologia , Transtornos de Deglutição/fisiopatologia , Doenças dos Nervos Cranianos/reabilitação , Nervos Cranianos/fisiopatologia , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/reabilitação , Humanos
20.
Rev Laryngol Otol Rhinol (Bord) ; 113(1): 77-80, 1992.
Artigo em Francês | MEDLINE | ID: mdl-1344516

RESUMO

The authors report four cases of severe deglutition disorders after partial laryngectomy. Three had collagen injection and one had a plastic reconstruction. They propose to use dynamic imagery in order to have a better selection of the patients.


Assuntos
Colágeno/administração & dosagem , Transtornos de Deglutição/reabilitação , Laringectomia/efeitos adversos , Faringectomia/efeitos adversos , Idoso , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Prega Vocal
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