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1.
Thorax ; 70(2): 115-20, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25422384

RESUMEN

BACKGROUND: Monitoring sputum eosinophils in asthma predicts exacerbations and improves management of asthma. Thus far, blood eosinophils and FE(NO) show contradictory results in predicting eosinophilic airway inflammation. More recently, serum periostin was proposed as a novel biomarker for eosinophilic inflammation. OBJECTIVES: Quantifying the mutual relationships of blood eosinophils, FE(NO), and serum periostin with sputum eosinophils by external validation in two independent cohorts across various severities of asthma. METHODS: The first cohort consisted of 110 patients with mild to moderate asthma (external validation cohort). The replication cohort consisted of 37 patients with moderate to severe asthma. Both cohorts were evaluated cross-sectionally. Sputum was induced for the assessment of eosinophils. In parallel, blood eosinophil counts, serum periostin concentrations and FENO were assessed. The diagnostic accuracy of these markers to identify eosinophilic asthma (sputum eosinophils ≥3%) was calculated using receiver operating characteristics area under the curve (ROC AUC). RESULTS: In the external validation cohort, ROC AUC for blood eosinophils was 89% (p<0.001) and for FE(NO) level 78% (p<0.001) to detect sputum eosinophilia ≥3%. Serum periostin was not able to distinguish eosinophilic from non-eosinophilic airway inflammation (ROC AUC=55%, p=0.44). When combining these three variables, no improvement was seen. The diagnostic value of blood eosinophils was confirmed in the replication cohort (ROC AUC 85%, p<0.001). CONCLUSIONS: In patients with mild to moderate asthma, as well as patients with more severe asthma, blood eosinophils had the highest accuracy in the identification of sputum eosinophilia in asthma. The use of blood eosinophils can facilitate individualised treatment and management of asthma. TRIAL REGISTRATION: NTR1846 and NTR2364.


Asunto(s)
Asma/sangre , Moléculas de Adhesión Celular/sangre , Eosinofilia/sangre , Eosinofilia/diagnóstico , Eosinófilos , Óxido Nítrico/análisis , Esputo/citología , Adulto , Área Bajo la Curva , Asma/complicaciones , Biomarcadores/análisis , Pruebas Respiratorias , Estudios Transversales , Progresión de la Enfermedad , Eosinofilia/complicaciones , Femenino , Humanos , Inflamación/sangre , Inflamación/patología , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Curva ROC , Índice de Severidad de la Enfermedad
2.
Br J Cancer ; 109(1): 215-8, 2013 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-23764750

RESUMEN

BACKGROUND: Thyroid function has been suggested to interfere with tumour biology and prognosis in different cancers. The present study was performed to investigate the impact of pre-therapeutic serum thyroid-stimulating hormone (TSH) levels on the prognosis of patients with endometrial cancer. METHODS: Pre-therapeutic serum TSH was investigated in 199 patients with endometrial cancer. After stratification in TSH risk groups, univariate and multivariable survival analyses were performed. RESULTS: Elevated TSH was independently associated with poor disease-specific survival in univariate/multivariable survival analyses (P=0.01 and P=0.03, respectively). CONCLUSION: Thyroid-stimulating hormone may serve as a novel and independent prognostic parameter for disease-specific survival in patients with endometrial cancer.


Asunto(s)
Neoplasias Endometriales/sangre , Neoplasias Endometriales/mortalidad , Tirotropina/sangre , Anciano , Neoplasias Endometriales/metabolismo , Femenino , Humanos , Estimación de Kaplan-Meier , Pronóstico , Glándula Tiroides/fisiología
3.
Psychol Belg ; 61(1): 186-199, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34249370

RESUMEN

This exploratory study assessed parents' perceptions of the emotional and behavioral impacts of the COVID-19 lockdown on their children. The total sample included 749 children, aged 4 to 13 years old (353 girls, 396 boys); 524 parents took part. The emotional and behavioral changes observed during the societal lockdown, family coexistence, the impact of COVID-19 on family well-being, and the frequency of social contacts before and during this lockdown were investigated. Results show that the most frequently reported difficulties were worry, agitation, anxiety, sadness, loneliness, nervousness, arguing, anger, frustration, boredom, irritability, behavioral problems, and laziness. Family coexistence declined significantly during this lockdown, and parents mentioned that COVID-19 had an impact on family well-being. Various ordinal logistic regressions showed that family coexistence, children's nervousness due to COVID-19, the impact of COVID-19 on family well-being, age, and social contacts before and during this lockdown seemed to explain the various emotional and behavioral changes observed in children during the societal lockdown. These results are discussed and recommendations are made.

4.
Int J Obes (Lond) ; 34(12): 1706-14, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20498659

RESUMEN

OBJECTIVE: This study aimed at the mapping and estimation of genetic and sex effects contributing to the obese phenotype of the Berlin Fat Mouse Inbred line 860 (BFMI860). This mouse line is predisposed for juvenile obesity. BFMI860 mice accumulate 24% total fat mass at 10 weeks of age under a standard maintenance diet. DESIGN: A total of 471 mice of a (BFMI860 x C57BL/6NCrl) F2 intercross population were fed a standard maintenance diet and were analysed for body composition at 10 weeks when they finished their rapid growth phase. RESULTS: The most striking result was the identification of a novel obesity locus on chromosome 3 (Chr 3) at 40 Mb, explaining 39% of the variance of total fat mass in the F2 population under a standard diet. This locus was named jObes1 (juvenile obesity 1). The BFMI860 allele effect was recessive. Males and females homozygous at jObes1 had on average 3.0 and 3.3 g more total fat mass at 10 weeks than the other two genotype classes, respectively. The effect was evident in all white adipose tissues, brown adipose tissue and also in liver. The position of the Chr 3 effect is syntenic to an obesity locus in humans. Additional loci for total fat mass and different white adipose tissue weights with minor effects were detected on mouse Chr 5 and 6. Another locus on Chr 4 had influence especially on liver weight. Many loci including jObes1 affected males and females to a different extent. CONCLUSION: The major locus on Chr 3 for juvenile obesity and its interaction with sex is unique and makes the BFMI860 mice an interesting resource for the discovery of novel genetic factors predisposing obesity, which might also contribute to obesity in humans. The results suggested that metabolic and regulatory pathways differed between the sexes.


Asunto(s)
Tejido Adiposo/metabolismo , Obesidad/genética , Animales , Composición Corporal/genética , Cruzamiento , Cruzamientos Genéticos , Dieta , Femenino , Genotipo , Masculino , Ratones , Ratones Endogámicos , Obesidad/metabolismo , Fenotipo , Factores Sexuales
5.
J Appl Genet ; 51(2): 193-7, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20453306

RESUMEN

The melanocortin-4 receptor (Mc4r) plays an important role in body-weight regulation. This study examines the methylation status and expression levels of the Mc4r gene in response to a standard and a high-fat diet in the obese Berlin fat mouse inbred (BFMI) line and the lean C57BL/6NCrl (B6) line of Mus musculus. The methylation status of CpG sites located within the Mc4r exon was analyzed by bisulfite genomic sequencing of genomic DNA of brain tissues, and gene expression analysis was performed by real-time PCR. In both lines, the methylation of CpGs 1-8 (near the transcription start) was lower than methylation of CpGs 9-16 (located towards the end of the selected amplicon). On the standard diet, the methylation status did not differ between the lines. In response to high-fat diet, methylation of the CpGs near the transcription start was decreased in both lines. The Mc4r gene expression, however, was only marginally increased in BMFI mice, whereas there was no change in B6 mice. The results suggest that a long-term high-fat diet might have an effect on the methylation status of the Mc4r gene. However, the effect of methylation on Mc4r expression seems to be a variable compensated by other regulating factors in a line-specific manner.


Asunto(s)
Ratones Obesos/genética , Obesidad/genética , Receptor de Melanocortina Tipo 4/genética , Delgadez/genética , Animales , Secuencia de Bases , Metilación de ADN , Cartilla de ADN , Ratones , Ratones Endogámicos C57BL/genética , Ratones Endogámicos/genética , Obesidad/veterinaria , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , Especificidad de la Especie , Delgadez/veterinaria , Transcripción Genética
6.
Sci Total Environ ; 372(2-3): 515-31, 2007 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-17140642

RESUMEN

The investigation aimed primarily at understanding the PAH record in inter-tidal mussel tissues and evaluating the bivalve performance as a bioindicator for oil contamination. The species Perna perna was used as test organism since it is abundantly distributed in coastal areas of the Americas, Africa and elsewhere. The study was carried out in Guanabara Bay and comprised two observation phases: phase one included seasonal sampling in 8 sites, whereas in phase two 4 sites were examined over 4 years. Among the 35 determined PAH (60-90 microg kg(-1) up to 4000-6000 microg kg(-1)) alkylated homologues predominated by more than 80%. The PAH profile in inter-tidal mussels is largely petrogenic with high contribution of dibenzothiophenes (DBT) and phenanthrenes (Ph). The prevailing petrogenic fingerprint, confirmed by diagnostic ratios, is linked to the properties of the inter-tidal habitat, which favors exposure to oil films. C2DBT/C2Ph and C3DBT/C3Ph ratios, however, show a wide range of values uncorrelated to specific oils. Micronucleus frequencies are significantly related to PAH concentrations, especially to those of alkylated homologues. Genotoxic expression appears at concentrations as low as 300 microg kg(-1) summation operator 35 PAH.


Asunto(s)
Monitoreo del Ambiente/métodos , Perna/química , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Brasil , Análisis Factorial , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Hidrocarburos Policíclicos Aromáticos/toxicidad , Factores de Tiempo , Contaminantes Químicos del Agua/toxicidad
7.
Mar Pollut Bull ; 54(3): 329-38, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17196223

RESUMEN

The mussel Perna perna was used to monitor and assess areas suspected of oil contamination by transplanting animals from unimpacted to impacted sites and vice versa. The deployment lasted for three months during which total PAH were measured in seawater samples collected every 15 days. PAH concentrations were determined in mussel tissue monthly. The lysosomal neutral red assay and the condition index were used as biomarkers of the adverse biological effects. The PAH concentration in mussels at unimpacted sites, prior to deployment was ca. 100 microg kg(-1) but increased to 300 microg kg(-1) after three months at the contaminated site. Mussels transplanted to the uncontaminated site showed a decrease from 380 to 80 microg kg(-1). Significant changes in lysosomal stability occurred within one month of the beginning of the transposition; in contrast condition indexes were not correlated with the observed changes in PAH concentration.


Asunto(s)
Monitoreo del Ambiente/métodos , Perna/efectos de los fármacos , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Animales , Agua de Mar/química
8.
Mar Pollut Bull ; 123(1-2): 291-303, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28847632

RESUMEN

References areas are sites that have undergone little or no anthropogenic impact and therefore represent the natural state of an environment. The objective of this study was to test if the Camamu Bay (CB), Bahia, can be used as a reference area for tropical coastal environments. Trace and major elements, polycyclic aromatic hydrocarbons (PAH), and the structure of the benthic macrofauna were determined. To compare the studied sites and identify the possible occurrence of anomalous concentrations, trace elements were normalized by Al and linear regressions were also performed. For all trace elements (except Cu), regressions showed a significant correlation (p<0.05) and few outliers (<3% of cases), showing that the concentrations found represent natural values for this bay. In the case of Cu, the highest concentrations were found near small municipalities, which may be associated with domestic sewage. About 60% of the organic compounds occurred at levels below the limit of quantification (<0.26ngg-1). The sum of PAHs was low for all stations, ranging from 1.17 to 313ngg-1. The benthic assemblages also indicated that the CB is a healthy, well-preserved ecosystem that deserves conservation efforts. The integrated use of geochemical and biotic data supported the use of CB as a reference area. Capsule: Organic and inorganic contaminants together with macrobenthic assemblages indicated that Camamu Bay is a pristine, tropical reference area.


Asunto(s)
Monitoreo del Ambiente/normas , Contaminantes Químicos del Agua/análisis , Animales , Organismos Acuáticos , Bahías , Brasil , Ecosistema , Monitoreo del Ambiente/métodos , Metales/análisis , Compuestos Orgánicos/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Aguas del Alcantarillado , Clima Tropical
9.
Neuropsychologia ; 43(12): 1713-20, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16154446

RESUMEN

Multi-channel near-infrared spectroscopy (NIRS) is a relatively new method to investigate the brain activation, based on changes in oxygenated haemoglobin (O2Hb) and deoxygenated haemoglobin (HHb). Recently, it has been shown that NIRS seems to be able to detect even small changes in O2Hb and HHb concentration due to cognitive demands. This study aimed at investigating the changes in O2Hb and HHb concentrations of the parietal cortex during a spatial task, a modified version of the Benton Line Orientation Task [Gur, R. C., Alsop, D., Glahn, D., Petty, R., Swanson, C. L., Maldjian, J. A., et al. (2000). An fMRI study of sex differences in regional activation to a verbal and a spatial task. Brain & Language, 74(2), 157-170.]. Twenty-four subjects were measured with NIRS while they had to estimate the orientation of a given line or to name the colour of the line in the control condition. Both conditions consisted of three activation phases each lasting 30 s, with a 10 s baseline and a 20 s post resting period. For assessing the changes in O2Hb and HHb concentrations, we measured with 24 NIRS channels over the parietal cortex using the NIRS apparatus ETG-100 (Hitachi Medical Ltd.). O2Hb concentration significantly increased during the active phase compared to the baseline for both conditions, but was significantly higher in the active phase for the line orientation condition compared to the colour naming condition bilaterally parieto-occipital. For the HHb concentrations, we only found significant decreases for both conditions but no differences between the conditions. The results of our study underscore the value of multi-channel NIRS for assessing cortical activation during cognitive tasks.


Asunto(s)
Mapeo Encefálico , Hemoglobinas/metabolismo , Oxihemoglobinas/metabolismo , Lóbulo Parietal/metabolismo , Percepción Espacial/fisiología , Espectroscopía Infrarroja Corta , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Lóbulo Parietal/irrigación sanguínea , Estimulación Luminosa/métodos
10.
J Endocrinol ; 187(2): 205-15, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16293768

RESUMEN

Adult roe deer males show hormonally controlled seasonal cycles of testicular growth and involution. Mediation of endocrine signals likely requires variable production of testicular growth factors for regulation of testis function. Here we studied the expression pattern of transforming growth factors (TGFs) beta1 and beta3. Total RNA from testis parenchyma was extracted monthly and analysed using quantitative reverse transcriptase PCR. The localization of mRNAs was determined by in situ hybridization, and corresponding proteins were visualized immunohistochemically. Both factors showed different expression levels and different seasonal expression patterns. The TGF-beta1 mRNA content was up to 45 times higher than that of TGF-beta3. Compared with its lowest level in May, TGF-beta1 expression was slightly enhanced during pre-rut (June/July). TGF-beta3 expression increased 5-fold from April to June/July and decreased thereafter to its low in December. This corresponded with changing numbers of spermatocytes and round spermatids, in which both TGF-beta3 mRNA and the protein were mainly localized. The TGF-beta1 mRNA was found in interstitial cells, mainly during the non-breeding season, but also in spermatocytes and spermatids during activated spermatogenesis. The translation product was localized in few spermatogenic cells only. The results suggest that TGF-beta1 and -beta3 are important in regulating seasonal spermatogenesis of roe deer with diverse functions affecting interstitial and spermatogenic cells.


Asunto(s)
Ciervos/metabolismo , Isoformas de Proteínas/metabolismo , Estaciones del Año , Espermatogénesis/fisiología , Testículo/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Inmunohistoquímica/métodos , Hibridación in Situ , Masculino , Isoformas de Proteínas/análisis , Isoformas de Proteínas/genética , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Testículo/química , Factor de Crecimiento Transformador beta/análisis , Factor de Crecimiento Transformador beta/genética
11.
Biol Psychol ; 69(3): 315-31, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15925033

RESUMEN

Near-infrared spectroscopy (NIRS) is an optical method, which allows non-invasive in vivo measurements of changes in the concentration of oxygenated (O2Hb) and deoxygenated (HHb) hemoglobin in brain tissue. In the present study we investigated 10 healthy subjects by means of multi-channel NIRS (Optical Topography; ETG-100, Hitachi Medical Co., Japan) during performance of congruent and incongruent trials of the Stroop color word task. With a similar pattern of activation for both congruent and incongruent Stroop trials in the NIRS channels located left superior-frontally, the results for O2Hb and the total amount of hemoglobin (Hb-tot) indicate specific activation for interference trials in inferior-frontal areas of the left hemisphere. This result is in line with several neuroimaging studies (fMRI, PET) that have already investigated the frontal activation related to Stroop interference, which further supports the assumption that multi-channel NIRS is sensitive enough to detect spatially specific activation during the performance of cognitive tasks.


Asunto(s)
Cognición/fisiología , Corteza Prefrontal/metabolismo , Espectroscopía Infrarroja Corta , Adulto , Femenino , Hemoglobina Falciforme/metabolismo , Humanos , Masculino , Oxígeno/metabolismo
12.
Mar Environ Res ; 59(5): 435-52, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15603768

RESUMEN

An integrated biological-chemical survey of organotin compounds was carried out in Guanabara Bay, the second most important Brazilian harbor complex. The biological survey revealed high levels of imposex in Stramonita haemastoma populations. Inside the bay values of relative penis length index from 42.7 to 107.6 and vas deferens sequence index from III to VI were found, while organisms collected outside the bay had values ranging from <0.1 to 35.2 and from 0 to II. None of the females sampled inside the bay were normal and imposex was found in all stations. Surface sediments in the bay are contaminated by tributyltin (10-522 ng/g d.w.) and triphenyltin (<3.9-39.4 ng/g d.w.) with greater concentrations close to shipyards and marinas. The observed predominance of parent compounds (TBT and TPT) is commonly found when recent inputs occur, but may also indicate slow degradation processes in the anoxic conditions of these sediments. To our knowledge, this is the first report of a combined imposex-sediment approach to evaluate organotin contamination in marine environments of South America, and also the first report of TPT detection in environmental matrices in this region.


Asunto(s)
Trastornos del Desarrollo Sexual/inducido químicamente , Trastornos del Desarrollo Sexual/veterinaria , Compuestos Orgánicos de Estaño/envenenamiento , Caracoles/anatomía & histología , Compuestos de Trialquiltina/envenenamiento , Contaminantes Químicos del Agua/envenenamiento , Animales , Brasil , Monitoreo del Ambiente , Femenino , Sedimentos Geológicos/química , Masculino , Caracoles/fisiología
14.
Environ Sci Pollut Res Int ; 22(19): 14767-80, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25989861

RESUMEN

Polycyclic aromatic (46 PAHs) and aliphatic hydrocarbons (C12-C40) were studied in atmospheric particulate matter sampled in Rio de Janeiro Metropolitan Area (RJMA). In total, 236 samples from six different sites were collected simultaneously and weekly over 1 year (January-December 2011) allowing a robust atmospheric characterization of fine particulate matter (PM2.5). Hydrocarbon concentration was in general low compared to previous studies in the area (PAHs range 0.25-19.3 ng m(-3)), possibly due to changes in fuel composition over time. Precipitation is the main meteorological parameter that rules particulate and hydrocarbon concentration, modifying PAH typology by scavenging. Aliphatic and aromatic diagnostic ratios gave indications conflicting with combustion features. However, ratios showed differences among sites. Principal component analysis (PCA) associated to multiple linear regressions (MLR) allowed quantitative estimate of sources and effectively indicated vehicular emission as the main hydrocarbon source in the atmospheric particulate matter.


Asunto(s)
Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Brasil , Ciudades , Monitoreo del Ambiente , Humanos , Estaciones del Año , Clima Tropical , Emisiones de Vehículos/análisis
15.
Anim Reprod Sci ; 64(1-2): 65-75, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11078967

RESUMEN

Roe deer is a seasonal breeder characterised by a short rutting season in summer. Mature males show synchronised cycles of testicular involution and recrudescence. Therefore, this species is a valuable model to study seasonal regulation of spermatogenesis in ruminants. It is hypothesised that a time-dependent production of testicular growth factors is required to regulate seasonal changes in testis growth and spermatogenesis. To identify potential candidates, total RNA from roe deer testis tissue was extracted at three different seasonal periods (April, August, December), and using RT-PCR the presence of several growth factors (aFGF, bFGF, IGF-I, IGF-II, TGF-alpha, TGF-beta1, TGF-beta3 and two isoforms of VEGF) was detected. Sequencing of the growth factor PCR fragments revealed a high sequence homology between cattle and roe deer. To further explore the expression patterns of the identified growth factors in roe deer their expression levels were standardised using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene expression. The study demonstrates the expression of several growth factors in roe deer testis and supports the assumption of their seasonally diverse regulation. These results provide the basis to investigate the role of growth factors in the regulation of circannual changes of testicular activity.


Asunto(s)
Ciervos/fisiología , Sustancias de Crecimiento/análisis , Espermatogénesis/fisiología , Testículo/fisiología , Animales , ADN/química , Cartilla de ADN/química , Electroforesis en Gel de Agar/veterinaria , Factores de Crecimiento Endotelial/análisis , Factor 1 de Crecimiento de Fibroblastos/análisis , Factor 2 de Crecimiento de Fibroblastos/análisis , Factor I del Crecimiento Similar a la Insulina/análisis , Factor II del Crecimiento Similar a la Insulina/análisis , Linfocinas/análisis , Masculino , ARN/química , ARN/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Estaciones del Año , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Testículo/química , Factor de Crecimiento Transformador alfa/análisis , Factor de Crecimiento Transformador beta/análisis , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
16.
Anim Reprod Sci ; 57(3-4): 237-49, 1999 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-10610042

RESUMEN

Testes of mink were compared between the breeding (March) and non-breeding seasons with the start (November) and cessation (May) of spermatogenic activity. Testicular mass and spermatozoa per gram testis were assessed. Percentages of haploid (1C), diploid (2C) and tetraploid (4C) cells were monitored using DNA flow cytometry and the proportions of somatic and spermatogenetic cells were determined after selective labelling of somatic cells with a vimentin antibody. Apoptosis was examined by cell death detection ELISA, and testosterone concentrations were measured with an enzyme-immunoassay. The significantly higher testis mass during the breeding period coincided with higher numbers of testicular spermatozoa per gram testis and peak of testicular testosterone concentration in comparison with non-breeding periods. The proportions of 1C, 2C and 4C cells showed corresponding strong differences between these periods with the maximum of 1C cells during breeding. The proportions of testicular cells in G2-M phase of mitosis were very low during the period of peak spermatogenesis; they were markedly increased in the time of autumnal resumption in November but were even higher during testis involution in May. However. the meiotic transformation (1C:4C ratio) is maximal in March. The total as well as the relative proportions of spermatogenic and somatic cells differed significantly not only between breeding and non-breeding periods but also between the periods at the start and at the end of active spermatogenesis. The intensity of apoptosis was also seasonally dependent. The highest level in March indicates a stimulated apoptosis even during the breeding period. In conclusion, the production of spermatozoa in mink is intensified by enlargement of gonads as well as enhanced efficiency of spermatogenesis during breeding. In this time, the testosterone concentration and the meiotic transformation show high levels, but the mitotic activity of spermatogenic cells is already significantly diminished and an intensified apoptosis seems to precede the forthcoming testis involution after breeding. The results suggest that the regulation of seasonal testicular activity is characterised by co-ordinated shifts in the relationships between mitosis, meiosis, apoptosis and testosterone production.


Asunto(s)
Apoptosis/fisiología , Meiosis/fisiología , Visón/fisiología , Mitosis/fisiología , Testículo/fisiología , Animales , Anticuerpos Monoclonales , ADN/inmunología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Citometría de Flujo/veterinaria , Técnica del Anticuerpo Fluorescente Indirecta/veterinaria , Técnicas para Inmunoenzimas/veterinaria , Masculino , Estaciones del Año , Espermatozoides/fisiología , Estadísticas no Paramétricas , Testículo/citología , Testosterona/análisis
17.
Theriogenology ; 59(7): 1487-502, 2003 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-12559454

RESUMEN

Roe deer are seasonal breeders with a short rutting season from mid-July to mid-August. The seasonality of reproductive activity in males is associated with cyclic changes between growth and involution of both testes and the accessory sex glands. This study characterizes morphological and functional parameters of these organs prior to, during and after breeding season in live adult roe deer bucks. Size and morphology of the reproductive tract was monitored monthly by transcutaneous (testes, epididymis) and transrectal (accessory glands) ultrasonography. Semen was collected by electroejaculation. Concentration, motility and morphological integrity of spermatozoa as well as the content of proteins and testosterone in semen plasma were evaluated. Proportions of haploid, diploid and tetraploid cells were estimated by flow cytometry in testicular tissue biopsies. Serum testosterone was measured by enzyme immunoassay. Most parts of the male reproductive tract showed distinct circannual changes in size and texture. These changes were most pronounced in the testes, seminal vesicles, and prostate. All reproductive organs were highly developed during the rut only. The volume of ejaculates, total sperm number and percentages of motile and intact spermatozoa also showed a maximum during this period and corresponded with high proportions of haploid cells in the testis. The highest percentages of tetraploid cells were found in the prerutting period. The production of motile and intact spermatozoa correlated with both the protein content of semen plasma and the concentration of testosterone in semen plasma and blood serum. These results suggest the importance of combined actions of the testes and accessory sex glands and the crucial role of testosterone in facilitating the optimal timing of intensified semen production to ensure sufficient numbers of normal spermatozoa in seasonal breeders.


Asunto(s)
Ciervos/fisiología , Próstata/fisiología , Estaciones del Año , Vesículas Seminales/fisiología , Espermatogénesis/fisiología , Testículo/fisiología , Animales , Citometría de Flujo/veterinaria , Masculino , Próstata/diagnóstico por imagen , Semen/citología , Semen/fisiología , Vesículas Seminales/diagnóstico por imagen , Recuento de Espermatozoides/veterinaria , Motilidad Espermática , Espermatozoides/citología , Testículo/diagnóstico por imagen , Testosterona/sangre , Testosterona/fisiología , Ultrasonografía
18.
Z Arztl Fortbild Qualitatssich ; 94(10): 854-8; discussion 862-3, 2000 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-11190923

RESUMEN

Permanently rising costs--especially caused by the high proportion of staffing costs (depending on the system)--conflict with a continuous budgetary coverage and the consequent exhaustion of an individual hospital's commercial reserves. The solution to this problem cannot be found by making far-reaching staff cuts, because the liability law alone already presents an insurmountable hurdle in this respect. Furthermore, the pressure on hospitals for rationalization is increased because high legal requirements--such as are given for example by the law regulating working hours--must be implemented in practice. There is a need for new, intelligent solutions in order to satisfy the legal requirements to their full extent. The responsible senior consultants, who will in future hold the function of "health managers" with budgetary responsibility, must be able to fulfill these new duties as well as further ones. It is the legislator's task to create the requisite legal basis--especially in Labour law.


Asunto(s)
Presupuestos/legislación & jurisprudencia , Costos de Hospital/legislación & jurisprudencia , Cuerpo Médico de Hospitales/legislación & jurisprudencia , Programas Nacionales de Salud/legislación & jurisprudencia , Garantía de la Calidad de Atención de Salud/legislación & jurisprudencia , Control de Costos/legislación & jurisprudencia , Alemania , Humanos , Admisión y Programación de Personal/legislación & jurisprudencia
19.
Environ Technol ; 24(6): 665-70, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12868520

RESUMEN

The reliability of enzyme-linked immunosorbent assay (ELISA) tests as a screening technique to address groundwater contamination was tested in an area following leakage of gasoline from a petrol station. Immunoassay data of benzene, toluene, ethylbenzene, and o-, m- and p-xylene (BTEX) were compared with results obtained using capillary gas chromatographic analysis. Detection limits were of 20 microg l(-1) for ELISA and 0.3 microg l(-1) for gas chromatography with flame ionization and photoionization detectors (GC-FID/PID) determination. Despite an observed overestimation of BTEX concentrations as given by ELISA, the tests responded reliably to different levels of contamination.


Asunto(s)
Derivados del Benceno/análisis , Benceno/análisis , Monitoreo del Ambiente/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Contaminantes del Suelo/análisis , Tolueno/análisis , Contaminantes Químicos del Agua/análisis , Xilenos/análisis , Anticuerpos/inmunología , Derivados del Benceno/inmunología , Ensayo de Inmunoadsorción Enzimática/normas , Gasolina , Sensibilidad y Especificidad , Tolueno/inmunología , Xilenos/inmunología
20.
Nutr Diabetes ; 3: e62, 2013 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-23507966

RESUMEN

Obesity has been associated with a higher risk of mortality, whereas caloric restriction reduces the risk. In this study, we examined how body weight development during life affects lifespan in a mouse model for obesity. Therefore, mice of the Berlin Fat Mouse Inbred line were set on either a standard or a high-fat diet (HFD). Median lifespans of standard diet-fed mice were 525 and 539 days for males and female animals, respectively. HFD feeding further decreased lifespan by increasing the risk of mortality. Our data provide evidence that the highest body weight reached in lifetime has only a minor effect on lifespan. More important is the age when the highest body weight is reached, which was positively correlated with lifespan (r=0.77, P<0.0001). Likewise, the daily gain of body weight was negatively correlated with the age of death (r=-0.76, P<0.0001). These data indicate that rapid weight gain in early life followed by rapid weight loss affect lifespan more than the body weight itself. These data suggest that intervention strategies to prevent rapid weight gain are of high impact for a long lifespan.

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