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1.
Arch Orthop Trauma Surg ; 136(4): 571-8, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26914332

RESUMEN

BACKGROUND: Four-corner fusion is a standard procedure for advanced carpal collapse. Several operative techniques and numerous implants for osseous fixation have been described. Recently, a specially designed locking plate (Aptus©, Medartis, Basel, Switzerland) was introduced. The purpose of this study was to compare functional results after osseous fixation using K-wires (standard of care, SOC) with four-corner fusion and locking plate fixation. METHODS: 21 patients who underwent four-corner fusion in our institution between 2008 and 2013 were included in a retrospective analysis. In 11 patients, osseous fixation was performed using locking plates whereas ten patients underwent bone fixation with conventional K-wires. Outcome parameters were functional outcome, osseous consolidation, patient satisfaction (DASH- and Krimmer Score), pain and perioperative morbidity and the time until patients returned to daily work. Patients were divided in two groups and paired t-tests were performed for statistical analysis. RESULTS: No implant related complications were observed. Osseous consolidation was achieved in all cases. Differences between groups were not significant regarding active range of motion (AROM), pain and function. Overall patient satisfaction was acceptable in all cases; differences in the DASH questionnaire and the Krimmer questionnaire were not significant. One patient of the plate group required conversion to total wrist arthrodesis without implant-related complications. CONCLUSION: Both techniques for four-corner fusion have similar healing rates. Using the more expensive locking implant avoids a second operation for K-wire removal, but no statistical differences were detected in functional outcome as well as in patient satisfaction when compared to SOC.


Asunto(s)
Artrodesis/métodos , Placas Óseas , Hilos Ortopédicos , Huesos del Carpo/cirugía , Satisfacción del Paciente/estadística & datos numéricos , Articulación de la Muñeca/cirugía , Adulto , Anciano , Artrodesis/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Rango del Movimiento Articular , Estudios Retrospectivos , Articulación de la Muñeca/fisiología
2.
Transl Psychiatry ; 5: e673, 2015 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-26529426

RESUMEN

Impairments in emotion regulation are thought to have a key role in the pathogenesis of anxiety disorders, but the neurobiological underpinnings contributing to vulnerability remain poorly understood. It has been a long-held view that exaggerated fear is linked to hyperresponsivity of limbic brain areas and impaired recruitment of prefrontal control. However, increasing evidence suggests that prefrontal-cortical networks are hyperactive during threat processing in anxiety disorders. This study directly explored limbic-prefrontal neural response, connectivity and heart-rate variability (HRV) in patients with a severe anxiety disorder during incidental versus intentional emotion regulation. During 3 Tesla functional magnetic resonance imaging, 18 participants with panic disorder and 18 healthy controls performed an emotion regulation task. They either viewed negative images naturally (Maintain), or they were instructed to intentionally downregulate negative affect using previously taught strategies of cognitive reappraisal (Reappraisal). Electrocardiograms were recorded throughout to provide a functional measure of regulation and emotional processing. Compared with controls, patients showed increased neural activation in limbic-prefrontal areas and reduced HRV during incidental emotion regulation (Maintain). During intentional regulation (Reappraisal), group differences were significantly attenuated. These findings emphasize patients' ability to regulate negative affect if provided with adaptive strategies. They also bring prefrontal hyperactivation forward as a potential mechanism of psychopathology in anxiety disorders. Although these results challenge models proposing impaired allocation of prefrontal resources as a key characteristic of anxiety disorders, they are in line with more recent neurobiological frameworks suggesting that prefrontal hyperactivation might reflect increased utilisation of maladaptive regulation strategies quintessential for anxiety disorders.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiopatología , Electrocardiografía , Emociones/fisiología , Imagen por Resonancia Magnética , Trastorno de Pánico/fisiopatología , Adulto , Femenino , Humanos , Masculino , Estimulación Luminosa , Factores Socioeconómicos
3.
Eur J Cancer ; 51(4): 514-521, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25623438

RESUMEN

BACKGROUND: Increases in incidence of oropharyngeal squamous cell carcinoma (OPSCC) in countries with falling tobacco use have been attributed to a growing role of human papilloma virus (HPV) in the carcinogenesis. Trends of HPV prevalence in populations with persistently high portions of smokers are poorly characterised. PATIENTS AND METHODS: Registry data from East Germany were used to determine incidence trends between 1998 and 2011. Data from patients treated at the Charité University Medicine Berlin between 2004 and 2013 (cohort 1, N=436) were used for estimation of trends in HPV prevalence, smoking and survival. HPV prevalence was prospectively confirmed in cohort 2 (N=213) comprising all primary HNSCC cases at the Charité in 2013. RESULTS: Between 1998 and 2011 incidence of both OPSCC and non-OPSCC increased. An increase in HPV prevalence (% of HPV+ cases in 2004-2006 versus 2012-2013: 27% versus 59%, P=0.0004) accompanied by a moderate decrease in the portion of current smokers was observed in OPSCC but not in non-OPSCC. The change in disease epidemiology in OPSCC was associated with significant improvement in overall survival. Increased HPV prevalence in OPSCC (48%) compared to non-OPSCC (11%) was confirmed in cohort 2. CONCLUSIONS: Despite clear differences to the United States in terms of tobacco use, the increase in OPSCC incidence in a European population was also mainly attributed to HPV, and the HPV status significantly affected prognosis. For clinical trial design it is important to consider the large group of smokers within HPV-induced OPSCC.


Asunto(s)
Carcinoma de Células Escamosas/epidemiología , Neoplasias de Cabeza y Cuello/epidemiología , Papillomaviridae/aislamiento & purificación , Fumar/efectos adversos , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/virología , Europa (Continente)/epidemiología , Femenino , Neoplasias de Cabeza y Cuello/etiología , Neoplasias de Cabeza y Cuello/virología , Humanos , Incidencia , Masculino , Fumar/epidemiología , Carcinoma de Células Escamosas de Cabeza y Cuello
4.
Psychol Med ; 45(7): 1447-58, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25382193

RESUMEN

BACKGROUND: Negative cognitive bias and aberrant neural processing of emotional faces are trait-marks of depression. Yet it is unclear whether these changes constitute an endophenotype for depression and are also present in healthy individuals with hereditary risk for depression. METHOD: Thirty healthy, never-depressed monozygotic (MZ) twins with a co-twin history of depression (high risk group: n = 13) or without co-twin history of depression (low-risk group: n = 17) were enrolled in a functional magnetic resonance imaging (fMRI) study. During fMRI, participants viewed fearful and happy faces while performing a gender discrimination task. After the scan, they were given a faces dot-probe task, a facial expression recognition task and questionnaires assessing mood, personality traits and coping strategies. RESULTS: High-risk twins showed increased neural response to happy and fearful faces in dorsal anterior cingulate cortex (ACC), dorsomedial prefrontal cortex (dmPFC), pre-supplementary motor area and occipito-parietal regions compared to low-risk twins. They also displayed stronger negative coupling between amygdala and pregenual ACC, dmPFC and temporo-parietal regions during emotional face processing. These task-related changes in neural responses in high-risk twins were accompanied by impaired gender discrimination performance during face processing. They also displayed increased attention vigilance for fearful faces and were slower at recognizing facial expressions relative to low-risk controls. These effects occurred in the absence of differences between groups in mood, subjective state or coping. CONCLUSIONS: Different neural response and functional connectivity within fronto-limbic and occipito-parietal regions during emotional face processing and enhanced fear vigilance may be key endophenotypes for depression.


Asunto(s)
Amígdala del Cerebelo/fisiopatología , Corteza Cerebral/fisiopatología , Trastorno Depresivo/fisiopatología , Emociones/fisiología , Expresión Facial , Reconocimiento Facial/fisiología , Sistema de Registros , Adulto , Dinamarca , Enfermedades en Gemelos , Endofenotipos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Gemelos Monocigóticos
5.
Psychol Med ; 44(2): 241-52, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23597109

RESUMEN

BACKGROUND: Short-term antidepressant administration has been reported to decrease amygdala response to threat in healthy volunteers and depressed patients. Neuroticism (N) is a risk factor for depression but has also been associated with slow or incomplete remission with antidepressant drug treatment. Our aim was to investigate early selective serotonin reuptake inhibitor (SSRI) administration neural effects on implicit processing of fearful facial expressions in volunteers with high levels of N. METHOD: Highly neurotic subjects received 20 mg/day citalopram versus placebo for 7 days in a double-blind, between-groups design. On the last day haemoperfusion and functional magnetic resonance imaging (fMRI) data during a gender discrimination task with fearful and happy faces were acquired. A control group of non-neurotic volunteers was also tested. RESULTS: High-N volunteers had reduced responses to threatening facial expressions across key neural circuits compared to low-N volunteers. SSRI treatment was found to elevate resting perfusion in the right amygdala, increase bilateral amygdalae activation to positive and negative facial expressions and increase activation to fearful versus happy facial expressions in occipital, parietal, temporal and prefrontal cortical areas. CONCLUSIONS: These results suggest that 7 days of SSRI administration can increase neural markers of fear reactivity in subjects at the high end of the N dimension and may be related to early increases in anxiety and agitation seen early in treatment. Such processes may be involved in the later therapeutic effects through decreased avoidance and increased learning about social 'threat' cues.


Asunto(s)
Antidepresivos/farmacología , Trastornos de Ansiedad/psicología , Adulto , Antidepresivos/administración & dosificación , Trastornos de Ansiedad/inducido químicamente , Trastornos de Ansiedad/tratamiento farmacológico , Citalopram/administración & dosificación , Citalopram/efectos adversos , Citalopram/farmacología , Discriminación en Psicología/fisiología , Método Doble Ciego , Femenino , Felicidad , Humanos , Imagen por Resonancia Magnética , Masculino , Modelos Psicológicos , Neuroticismo , Tiempo de Reacción , Inhibidores Selectivos de la Recaptación de Serotonina/administración & dosificación , Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Resultado del Tratamiento , Adulto Joven
6.
Bull Environ Contam Toxicol ; 92(3): 285-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24233261

RESUMEN

Using the comet assay, the genotoxicity of Cd, Zn and Cd/Zn mixtures in Eisenia andrei was assessed after 4 weeks of exposure at 15, 20 and 25 °C. Relative to the controls, significant increases in TDNA% were observed in exposures to Cd alone at 500 and 1,000 mg/kg soil at both 20 and 25 °C, while a general decrease occurred at 15 °C. For Zn alone, a decreasing trend in TDNA% occurred at all three temperatures with increasing Zn concentration. For the Cd/Zn mixtures at 15 °C, genotoxicity was reduced at all mixture concentrations relative to the control. At 20 °C, the genotoxic response was similar to the control at all exposures. At 25 °C, the response was elevated at the 50 + 50 and 250 + 250 mg/kg mixture concentrations. In the remaining treatments at 25 °C, TDNA% was similar to the values in the respective control. The lack of consistently significant mixture genotoxicity may indicate antagonistic interactions between Cd and Zn in the mixtures. However, this was not conclusively determined because temperature alone had an inconsistent effect upon TDNA% readings in the control exposures.


Asunto(s)
Cadmio/toxicidad , Contaminantes del Suelo/toxicidad , Zinc/toxicidad , Animales , Ensayo Cometa , Daño del ADN , Oligoquetos , Temperatura
7.
Artículo en Alemán | MEDLINE | ID: mdl-22138742

RESUMEN

OBJECTIVE: Hobby keeping of goats and sheep confronts veterinarians with new challenges that rarely have to be faced in livestock husbandry. During the last five years five goats were presented to the Clinic for Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Germany, with inappropriate lactation syndrome. Four of these animals had been previously treated with cabergoline without enduring success. According to the request of the owners (informed consent) and the clinical severity of the cases, a mastectomy was performed in all five animals. MATERIAL AND METHODS: Surgery was performed under general anaesthesia using ketamine and xylazine, and with the patients in a recumbent position. RESULTS: Mastectomy in small ruminants requires knowledge of the anatomy of the udder and the possible positions of the supplying blood vessels. Our patients displayed a variety of dispositions of the Vena epigastrica caudalis superficialis. Special attention should be paid to a careful and blunt dissection of the mammary gland, and immediate control of haemorrhage, to maintain a clear view on the anatomic structures. Furthermore, dissection of the glandular tissue should be strictly avoided to prevent milk contamination of the surgical area. A sufficient skin flap has to be left to cover the surgical area after removal of the udder. CONCLUSION AND CLINICAL RELEVANCE: Even though udder amputation appears to be a radical and high-risk procedure, all five goats survived the surgery. The wound healing occurred in a reasonable time without any severe complications. In goats that are kept as "hobby animals" and in which an inappropriate lactation syndrome cannot be treated conservatively, mastectomy is a reasonable and promising therapy.


Asunto(s)
Galactorrea/veterinaria , Enfermedades de las Cabras/cirugía , Mastectomía/veterinaria , Animales , Cabergolina , Agonistas de Dopamina/uso terapéutico , Ergolinas/uso terapéutico , Femenino , Galactorrea/tratamiento farmacológico , Galactorrea/cirugía , Enfermedades de las Cabras/tratamiento farmacológico , Cabras , Mastectomía/normas , Recurrencia , Colgajos Quirúrgicos/normas , Colgajos Quirúrgicos/veterinaria , Resultado del Tratamiento
8.
Ecotoxicol Environ Saf ; 74(7): 2070-4, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21831430

RESUMEN

In a recent study, we showed that the earthworm species Eisenia fetida, inhabiting an extremely high metal polluted compost heap on a wine farm, did not have elevated body loads of the metals but exhibited genotoxic tolerance when exposed to Cd in the laboratory (Voua Otomo and Reinecke, 2010). To unravel the mechanism behind the surprisingly low metal body burdens on one hand and genotoxic tolerance on the other hand, we investigated the estimated bioavailability of these metals (Cu, Zn, Pb and Cd) using sequential extraction methods with CaCl(2) and di-ethylene-triamine-pentaacetic acid (DTPA) and allozyme polymorphism in this field population, a laboratory control as well as a long-term Cd exposed population. The amounts of mobile (extracted with CaCl(2)) and mobilizable (extracted with DTPA) metals in relation to the total (extracted with nitric acid) metals were all below 0.05% for all four metals, suggesting low availability for uptake. The low availability of these metals could not be explained by physico-chemical properties of soil but by the phenomenon of aging of the metals. There was no difference in allozyme frequency between metal tolerant and non-metal tolerant populations of E. fetida. This suggested that the tolerance found in earlier studies could be a mere physiological adaptation.


Asunto(s)
Metales Pesados/farmacocinética , Oligoquetos/efectos de los fármacos , Oligoquetos/genética , Contaminantes del Suelo/farmacocinética , Suelo/química , Animales , Disponibilidad Biológica , Isoenzimas/genética , Oligoquetos/enzimología , Polimorfismo Genético
9.
Euro Surveill ; 16(50): 20040, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22221497

RESUMEN

In March 2010 the Rapid Alert System for Food and Feed (RASFF) was used to inform about Salmonella Montevideo in a herbal food supplement, formulated in capsules, distributed under a Dutch label in Germany. Simultaneous to the first RASFF notice, in the last two weeks of March 2010 an unusual number of 15 infections with S. Montevideo was notified within the electronic reporting system for infectious diseases at the Robert Koch Institute. Adult women (median age: 43, range: 1-90 years) were mainly affected. An outbreak was suspected and the food supplement hypothesised to be its vehicle. Cases were notified from six federal states throughout Germany, which required efficient coordination of information and activities. A case-control study (n=55) among adult women showed an association between consumption of the specific food supplement and the disease (odds ratio (OR): 27.5, 95% confidence interval (CI): 3.1-infinity, p-value=0.002). Restricting the case-control study to the period when the outbreak peaked (between 29 March and 11 April 2010) resulted in an OR of 43.5 (95% CI: 4.8-infinity, p-value=0.001). Trace-back of the supplement's main ingredient, hemp seed flour, and subsequent microbiological testing by pulsed-field gel electrophoresis supported its likely role in transmission. This outbreak investigation illustrates that information from RASFF may aid in hypothesis generation in outbreak investigations, though likely late in the outbreak.


Asunto(s)
Suplementos Dietéticos/microbiología , Brotes de Enfermedades , Intoxicación Alimentaria por Salmonella/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Alemania/epidemiología , Humanos , Lactante , Sistemas de Información , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Bull Environ Contam Toxicol ; 83(1): 19-22, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19434358

RESUMEN

This study investigated the effects of accumulated copper, on digestive epithelium height and percentage area, and on oocyte numbers of the snail Helix aspersa, in a vineyard where copper oxychloride is sprayed. The ultimate aim was to determine the usefulness of these cellular responses as biomarkers. Results showed that snails collected 2 months after fungicide application, had a significantly lower mean digestive epithelium height and percentage area, as well as significantly fewer oocytes per 1 mm(2) of ovotestis, compared to snails collected only 1 week after fungicide application and those from a control vineyard. It was concluded that these cellular responses are clear, measurable responses to copper oxychloride exposure and copper accumulation. However, they do not provide an early warning of copper exposure, which impacts on their usefulness as biomarkers.


Asunto(s)
Cobre/análisis , Exposición a Riesgos Ambientales , Fungicidas Industriales/análisis , Caracoles Helix/química , Animales , Biomarcadores/análisis , Monitoreo del Ambiente , Mucosa Gástrica/química , Mucosa Gástrica/citología , Caracoles Helix/citología , Oocitos/química , Oocitos/citología
11.
Chemosphere ; 75(3): 279-83, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19211128

RESUMEN

We studied the avoidance behaviour of Eisenia fetida and Aporrectodea caliginosa in OECD artificial soil spiked with NaCl and in natural saline soil (of varying ionic constitutions) collected from Robertson Experimental Farm (ROBS) in Western Cape, South Africa. For each organism, the ecotoxicological test was performed using a two-chamber test over a period of 48 h. The results showed that in the OECD soil, the avoidance EC50 (the concentration/electrical conductivity at which there is effect on 50% of the organisms) for A. caliginosa of 667 mg kg(-1) NaCl was lower than 1164 mg kg(-1) for E. fetida. Similarly in ROBS soil, the avoidance EC50 for A. caliginosa of 0.26 dS m(-1) was lower than 0.56 dS m(-1) in E. fetida. These results indicated that A. caliginosa showed better avoidance to salinity than E. fetida irrespective of soil types or ionic constitution. When compared with literature data, EC50 values in avoidance tests were either lower or comparable to those of reproduction, which was the most sensitive life-cycle parameter. The only exception was the EC50 value for avoidance of E. fetida in natural soil which was higher than for reproduction suggesting that the predictive value of the avoidance test for this species might be lower in natural soils. The variation in sensitivities of these earthworms could be as a result of differences in their eco-physiology. These findings suggest the relevance of the avoidance test as a suitable screening method showing first tendencies of saline stress on the habitat function of soils.


Asunto(s)
Oligoquetos/fisiología , Salinidad , Contaminantes del Suelo/toxicidad , Animales , Conducta Animal , Ecosistema , Monitoreo del Ambiente , Oligoquetos/crecimiento & desarrollo , Suelo , Contaminantes del Suelo/análisis
12.
Ecotoxicol Environ Saf ; 72(1): 99-107, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18715644

RESUMEN

We studied the effect of clay content on the bioavailability of zinc to pre-clitellate earthworm, Eisenia fetida in the laboratory using OECD artificial soil adjusted to 5%, 20%, and 40% clay. Batches of worms were exposed to a wide range of zinc concentrations. Mortality, growth, maturation (% clitellate), cocoon production, and body zinc concentrations were assessed over and after a period of 4 weeks. Total, DTPA, and CaCl(2) extractable zinc in the substrates were also determined. The results of the biological responses showed that interaction of clay and zinc had a significant influence on mortality but not on the other biological parameters. None of the three extraction methods showed consistent and significant effect of clay content on zinc partitioning. Although total, DTPA, and CaCl(2) extracts of zinc correlated strongly with one another and were in similar relation with the observed biological responses, only the CaCl(2) extract revealed a time dependent availability of this metal. It is concluded that clay content had no significant influence on sub-lethal toxicity of zinc to this earthworm over the range of exposure concentrations.


Asunto(s)
Silicatos de Aluminio/análisis , Oligoquetos/fisiología , Suelo/análisis , Zinc/metabolismo , Zinc/toxicidad , Silicatos de Aluminio/toxicidad , Animales , Bentonita/análisis , Bentonita/toxicidad , Cloruro de Calcio/análisis , Arcilla , Relación Dosis-Respuesta a Droga , Femenino , Caolín/análisis , Caolín/toxicidad , Masculino , Oligoquetos/efectos de los fármacos , Oligoquetos/crecimiento & desarrollo , Ácido Pentético/farmacología , Reproducción/efectos de los fármacos
13.
Arch Environ Contam Toxicol ; 53(3): 359-64, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17612782

RESUMEN

The objective of this study was to quantify the effects of zinc exposure on the histological structure of the hepatopancreas of Porcellio laevis. Woodlice were experimentally exposed to various concentrations (1000, 4000, and 8000 mg. kg(-1)) of zinc sulphate. Hepatopancreas samples of exposed isopods were histologically prepared and analysed with Leica QWin image analysis software. The B-cells in hepatopancreases of zinc sulphate - exposed woodlice were reduced in size to varying degrees, compared to that of the control, Percentage Cellular Area (PCA) of the hepatopancreas samples revealed that zoning occurred through the length of hepatopancreas lobes. Analysis of the PCA data of hepatopancreases of P. laevis exposed to the zinc sulphate revealed that there was a decline in PCA, in all the zones, compared to those in the control. The Z3 zone (the part from the middle to three quarters to the back of the tubule) was shown to be the best suited, if PCAs are to be considered as a biomarker in woodlouse toxicity studies.


Asunto(s)
Isópodos/efectos de los fármacos , Hígado/efectos de los fármacos , Páncreas/efectos de los fármacos , Sulfato de Zinc/toxicidad , Animales , Biomarcadores , Hígado/patología , Páncreas/patología
14.
Arch Environ Contam Toxicol ; 52(3): 363-70, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17354041

RESUMEN

Ultramafic soils are characterized by high concentrations of heavy metals of natural origin-such as chromium, cobalt, manganese, and nickel-as well as a shortage of primary nutrients. This can result in extremely disadvantageous living conditions for all soil-dwelling organisms. Responses to these conditions were addressed by studying growth, cocoon production, and fecundity of earthworms as endpoints of sublethal effects and how this influences the reproductive system and, consequently, population development. Mature specimens of two ecophysiologically different species of earthworms, Eisenia fetida (Savigny) and Aporrectodea caliginosa (Savigny), were exposed for 56 days to an uncontaminated soil and ultramafic soils collected from six ultramafic sites in the Barberton greenstone belt. In all ultramafic soil samples, the specimens of both species grew slower than those in the control soil. In A. caliginosa, an autotomization of the tail section was observed at higher concentrations of heavy metals. At high levels of heavy metals such as manganese, chromium, nickel, and cobalt, a significantly lower cocoon production was recorded for E. fetida, and at medium levels, a time delay in cocoon production was found. A. caliginosa showed an increase in production at medium levels and a decrease at high levels of heavy metals. In both species, no correlation between growth and cocoon viability was found, indicating different target levels for toxicants present in ultramafic soils. To determine effects of these soils on population dynamics, hatching success may be a more useful endpoint of reproduction.


Asunto(s)
Metales Pesados/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Monitoreo del Ambiente , Metales Pesados/análisis , Oligoquetos/crecimiento & desarrollo , Oligoquetos/fisiología , Reproducción/efectos de los fármacos , Suelo , Contaminantes del Suelo/análisis
15.
Ecotoxicol Environ Saf ; 66(2): 244-51, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16318873

RESUMEN

Earthworm population density was measured in and adjacent to an orchard in an agricultural area in the Western Cape, South Africa. Worm densities were very low in orchards (22/m(2)) compared to adjacent uncultivated fields (152/m(2)) at a distance from the orchards. The possible effect of organophosphate pesticides on the earthworms was investigated. Background soil concentrations of chlorpyrifos prior to the start of the spraying season were low (0.2-2.7 microg/kg) but persistent for up to 6 months after the last spraying event, and the pesticide was, as a result of rainfall, transported to nontarget areas by runoff. Background concentrations of azinphos methyl were higher than those of chlorpyrifos (1.6-9.8 microg/kg) but not detectable 2 weeks after a spraying event. Azinphos methyl was mostly transported by wind (spray drift) to adjacent areas. A microcosm study indicated effects of chlorpyrifos on earthworms as determined by measuring biomass change and Cholinesterase inhibition. It is concluded that earthworms were affected detrimentally by the pesticides due to chronic (chlorpyrifos) and intermittent (azinphos methyl) exposure.


Asunto(s)
Azinfosmetilo/toxicidad , Cloropirifos/toxicidad , Insecticidas/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Agricultura , Animales , Azinfosmetilo/análisis , Biomasa , Cloropirifos/análisis , Colinesterasas/metabolismo , Monitoreo del Ambiente , Insecticidas/análisis , Oligoquetos/enzimología , Oligoquetos/crecimiento & desarrollo , Densidad de Población , Contaminantes del Suelo/análisis , Sudáfrica
16.
Ecotoxicol Environ Saf ; 66(1): 92-101, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16324744

RESUMEN

Background levels of chlorpyrifos and earthworm abundance were determined in an orchard and adjacent areas on a farm in the Western Cape, South Africa before these areas were again sprayed with this organophosphate. The background concentrations ranged from 0.2 microg/kg dm in the spray drift area adjacent to the orchard to 10.18 microg/kg dm on the slope in the run off area. In the target area the chlorpyrifos concentrations varied from a mean of 15.25 +/- 10.0 microg/kg directly after spraying to a mean of 7.0 +/- 0.9 microg/kg 6 months later and in the nontarget area they varied from a mean of 55.0 +/- 35 microg/kg to 12.0 +/- 5 microg/kg after 6 months. Chlorpyrifos was therefore still present in the field soils, but at lower concentrations, up to 6 months after the last spraying event. Earthworm abundance and population densities were very low. Only Aporrectodea caliginosa was found and the densities were much lower in the orchards (22 per m(2)) than in the nontarget areas (98.3 per m(2)). Microcosm studies were undertaken to relate biomarker responses to chlorpyrifos with biomass changes. Microcosms were filled with soil from the same areas and earthworms of the species A. caliginosa were introduced. The microcosms were treated with a series of concentrations of chlorpyrifos in the laboratory under controlled conditions. These concentrations were chosen to fall within the background ranges found in the soils. The biomass of the worms was determined regularly for a period of 5 weeks and worms in a state of estivation were noted. Earthworms were removed from the microcosms for biomarker tests: for cholinesterase (ChE) inhibition assays every week and for a neutral red retention determination 2 weeks after the exposures started. The most prominent biomass loss was noted in earthworms exposed to the highest pesticide concentration of 8.0 microg/kg. Estivation was higher among earthworms exposed to higher exposure concentrations. Inhibition of ChE increased with higher exposure concentrations and with time but there was no clear dose-related response. A clear dose-related response with exposure concentration was established for the neutral red retention assay. A correlation between ChE inhibition and biomass change existed directly after the second application of chlorpyrifos.


Asunto(s)
Cloropirifos/toxicidad , Inhibidores de la Colinesterasa/toxicidad , Ecosistema , Insecticidas/toxicidad , Oligoquetos/efectos de los fármacos , Animales , Biomarcadores/análisis , Biomasa , Estivación/efectos de los fármacos , Densidad de Población
17.
Ecotoxicol Environ Saf ; 67(3): 361-8, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17173970

RESUMEN

The concept of species sensitivity differences is important in ecotoxicology and environmental risk assessment, but testing usually focuses on lethality of toxicants. The effects on the suborganismal level are mostly ignored; therefore, the present study assessed a biomarker of genotoxicity (the alkaline comet assay) to compare species sensitivities. Five earthworm species (Amynthas diffringens, Aporrectodea caliginosa, Dendrodrilus rubidus, Eisenia fetida and Microchaetus benhami) were exposed for 48 h to sublethal concentrations of cadmium sulphate in reconstituted soil water and DNA integrity was evaluated with the parameter Tail DNA %. Significant amounts of DNA damage were detected in three (A. caliginosa, D. rubidus and E. fetida) species. E. fetida exhibited the highest level of DNA damage, although D. rubidus showed the highest increase (3-fold) in DNA damage from the control. All exposed earthworms accumulated Cd, although body loads did not correspond with DNA damage levels; most of the Cd was probably sequestrated and rendered harmless.


Asunto(s)
Cadmio/toxicidad , Ensayo Cometa/métodos , Daño del ADN , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Ensayo Cometa/instrumentación , Monitoreo del Ambiente , Oligoquetos/clasificación , Oligoquetos/fisiología , Medición de Riesgo , Especificidad de la Especie
18.
Am J Transplant ; 6(5 Pt 1): 947-58, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16611330

RESUMEN

Recently, we generated cells with multipotent properties from blood monocytes that in vitro differentiate into various somatic cell types. This experimental study investigated whether these programmable cells of monocytic origin (PCMO) succeed to restore left ventricular function after myocardial infarction (MI). PCMO were generated from monocytes by exposition to RPMI medium containing M-CSF and IL-3 for 6 days. MI was induced in female Lewis rats ligating the left coronary artery. PCMO of male Lewis donors were injected either intramyocardially (i.my.) or intravenously (i.v.) 24 h or 6 days post-infarction. Hemodynamic assessment after 60 days demonstrated significant improvement of left ventricular function following i.my. transplantation of PCMO as well as early (24 h post-infarction) i.v. application while nonmodulated monocytes failed to restore heart function. The Y-chromosome-specific SRY gene of male donor PCMO was detected exclusively in infarcted hearts of animals, which demonstrated improved cardiac function. Subdivision of infarcted hearts by microdissection localized the SRY gene-containing department to the left ventricle adjacent to the infarcted area whereas the right ventricle remained negative. Successful generation of PCMO in access numbers allows their autologous use as a new additive treatment for early restoration of cardiac function after MI.


Asunto(s)
Pruebas de Función Cardíaca , Monocitos/trasplante , Infarto del Miocardio/terapia , Trasplante de Células Madre , Función Ventricular Izquierda , Animales , Capilares/patología , Circulación Coronaria , Modelos Animales de Enfermedad , Ecocardiografía , Femenino , Hemodinámica , Masculino , Reacción en Cadena de la Polimerasa , Ratas , Ratas Endogámicas Lew , Factor A de Crecimiento Endotelial Vascular/genética , Cromosoma Y
20.
Ecotoxicol Environ Saf ; 62(1): 99-111, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15978295

RESUMEN

To investigate the impact of copper-containing fungicides (copper oxychloride) on earthworms in South African vineyards, field inventories of earthworms in and between vine rows were carried out and compared to directly adjacent grassland. Also copper content, pH, organic matter content, and soil porosity were determined in these soils. This was combined with laboratory experiments to study the impact of vineyard soil characteristics on the burrowing and dispersal behavior of earthworms. Moreover, the direct toxic action of copper oxychloride on different endpoints of the earthworms (survival and growth) was studied. Copper oxychloride had a negative impact on these endpoints (decreased growth and survival related to increased copper body content) as well as on the behavioral aspect (decreased burrowing rate and avoidance of copper-containing soil). Moreover, there was an inverse relation between burrowing activity and soil bulk density that could also be related to the copper content. This may lead to a decrease in sustainable soil quality in vineyards.


Asunto(s)
Cobre/toxicidad , Fungicidas Industriales/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Agricultura , Animales , Conducta Animal/efectos de los fármacos , Conservación de los Recursos Naturales , Cobre/análisis , Oligoquetos/crecimiento & desarrollo , Oligoquetos/fisiología , Porosidad , Suelo/análisis , Sudáfrica , Pruebas de Toxicidad , Vitis
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