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1.
Animal ; 16(9): 100624, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36049262

RESUMO

Although it is still most common to rear dairy calves separately from adult cattle, the interest in prolonged contact between dairy calves and lactating cows during early life is increasing. Previous research has documented positive effects of cow-calf contact (CCC) on for example early calf growth and udder health of suckled cows, but also negative effects such as increased separation distress and reduced weight gains after weaning. The aim of this study was to use information from European farms with prolonged cow-calf contact to identify innovative solutions to common challenges for CCC farms. Commercial dairy farms that kept calves with adult lactating cows for seven days or more after birth were invited to participate, and interviews were performed with 104 farmers from six countries. During interviews, information about farm management, calf rearing, farmers' perception of animal health on their farm, and farmers' drivers and barriers for implementing CCC were collected. We found that CCC was practised in a large variety of housing and management systems, and that calves could be reared together with their dam, with foster cows, or using a combination of the two. The contact period varied considerably (7-305 days) between farms and about 25% of the farms manually milk fed the calves during parts of the milk feeding period. Daily contact time varied between farms, from 30 minutes per day to permanent contact except at milking. Behaviours indicative of separation distress, most commonly vocalisation in cows and calves, were reported by 87% of the farmers. Strategies to alleviate separation distress, for example simultaneous gradual weaning and separation, were used on some farms. Building constraints were most often mentioned as a barrier for implementing CCC. Our findings suggest that CCC is practised in a variety of commonly used husbandry systems. Reported challenges were primarily related to weaning and separation, and to building constraints; these aspects should be areas of future research.


Assuntos
Indústria de Laticínios , Lactação , Animais , Bovinos , Estudos Transversais , Fazendas , Feminino , Leite , Desmame
3.
Z Gerontol Geriatr ; 55(2): 143-149, 2022 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-35201395

RESUMO

BACKGROUND: In the spring of 2020 during the first wave of the pandemic an above-average number of residents and staff in nursing homes fell ill and accounted for the highest number of incidences. Due to the pandemic, managers in nursing homes had to make new decisions on a daily basis as well as interpret and integrate decisions made by higher level authorities. AIM OF THE STUDY: The aim was to describe the decisions that had to be made by the managers of nursing homes in dealing with the COVID-19 pandemic and related consequences. MATERIAL AND METHODS: A qualitative multicentre cross-sectional design was chosen. Data collection was conducted with semi-structured telephone interviews. The recorded audio data were transcribed, analyzed using the framework analysis method and reflected in peer debriefings. RESULTS: A total of 78 interviews were conducted in 43 nursing homes and 3 main themes with 10 subthemes emerged: decisions about social participation, decisions on quarantine and isolation and staff adjustments. DISCUSSION: Clearer information and directives for the implementation of measures are needed, e.g. through standardized guidelines nationwide. Additionally, public health departments should play a stronger and more responsible role in a pandemic situation. The consequences of their decisions were hardly foreseeable for the managers and were marked by uncertainty. Responsibilities for and consequences of pandemic-related decisions should be further evaluated to empower managers in times of crises.


Assuntos
COVID-19 , Pandemias , COVID-19/epidemiologia , Estudos Transversais , Humanos , Assistência de Longa Duração , SARS-CoV-2
4.
Animal ; 16(1): 100433, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34999564

RESUMO

Data from breeder hens and chicks are particularly critical for the development of vitamin B2 recommendations for organic poultry. To test safe thresholds of supplementation, 100 breeder hens (Hubbard JA 57 K) and ten cockerels were allocated to ten housing groups, with each receiving supplementation of either 4.0 (treatment CON) or 2.5 mg (treatment RED) riboflavin per kg feed. After 15 weeks of experimental feeding, 256 eggs were incubated. From the hatched chicks (Hubbard S757), 192 were allocated to four treatments based on their parents' treatment (CON- or RED-) and on their own supplementation of either 4.0 (-CON) or 2.5 mg (-RED) riboflavin per kg feed. Two groups of each combination (CON-CON, CON-RED, RED-CON, RED-RED), each with 24 chicks of both sexes, were fattened for nine weeks and slaughtered. Analysis of total riboflavin (sum of native concentrations and supplements) in the parent's feeds revealed an average, over the 15 weeks, of 7.8 and 5.8 mg per kg feed for CON and RED, respectively. Body weight, plumage integrity, gait appearance, footpad, claw and keel bone integrity, lesion scores, laying performance, and egg mass were found to be of similarly high levels for all hens without any treatment effects. Performance traits of the hens in both treatments reached the specifications of the producer for this genotype. Yolk and albumen riboflavin concentrations were not affected although yolk colour in the RED treatment group became darker. Fertility was not affected, and hatchability was 100 per cent. Total riboflavin concentrations in the broiler diets were on average, over 9 weeks, 8.2 and 6.1 mg/kg for CON and RED, respectively. In chicks, RED treatment of their parents led to significant depressions of feed intake and growth. The RED treatment of the chicks themselves also impaired growth. Growth rates of the CON-CON treatment were in line with the specifications of the producer for this genotype. Plumage scores, footpad integrity and walking appearance of the broilers, and dressing percentage of the carcasses were not affected by treatment. The RED treatment of chicks caused lower spleen and heart weights, while pancreas and liver weights, and liver riboflavin concentrations were not affected. In conclusion, supplementation of 4.0 mg/kg to organic diets did not evoke any health or performance problems for breeder hens or broiler chicks, while a supplementation level of 2.5 mg per kg feed led to reduced weight gains, although without any other riboflavin deficiency symptoms.


Assuntos
Ração Animal , Galinhas , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Feminino , Fertilidade , Masculino , Riboflavina
5.
Br Poult Sci ; 62(1): 1-7, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32812785

RESUMO

1. Ascarids (Ascaridia galli and Heterakis spp.) are highly prevalent in free-range laying hens. Ascarid eggs survive for long periods in soil, and one preventive measure is to add litter material to areas close to the henhouse. In this study, recovery rates of ascarid eggs from three common litter materials, namely pea gravel, beech (Fagus sylvatica) and spruce (Picea abies) wood chips were compared to recovery rates from soil. 2. Materials were mixed with faeces containing 1,408 ascarid eggs per g of faeces, placed in plastic fruit boxes and exposed to natural weather conditions in a randomised block design with six replicates per treatment. 3. Numbers of ascarid eggs were quantified at 28 time points over 3.5 years. Ascarid eggs were recovered for over three years from all materials and completely disappeared during the fourth winter of exposure. Time needed to get to a 50% reduction in ascarid eggs did not differ between litter materials and soil (242 to 269 days). A 99% reduction was reached significantly (P < 0.001) earlier in pea gravel (548 days) than in the three other materials, and earlier in the two wood chips (day 682 for beech, day 692 for spruce, P < 0.05) than in soil (1,277 days). 4. Accumulation of ascarid eggs in the area close to the henhouse can be reduced by any of the tested litter materials compared to bare soil. Adding litter to this area is highly recommended for free-range layer farmers in order to reduce numbers of infective ascarid eggs.


Assuntos
Galinhas , Doenças das Aves Domésticas , Animais , Feminino , Óvulo , Solo , Madeira
7.
Aging Ment Health ; 24(1): 162-170, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30381955

RESUMO

Objectives: To identify correlates of self-rated and proxy-rated quality of life (QoL) in people with dementia on (i) a dementia-specific and (ii) a capability-wellbeing QoL measure at baseline and 12-month follow-up, and to consider such factors in the context of QoL intervention development.Method: Prospective clinical and demographic data were collected from 451 community-dwelling dyads (mild-moderate dementia) across eight European countries. QoL was measured using the QOL-AD and the ICECAP-O. Multivariate modelling identified correlates of self- and proxy-rated QoL at baseline and at 12-month follow-up.Results: Carer's proxy-ratings of QoL were significantly lower than self-ratings at all time-points for both measures. Proxy-ratings declined over time, but self-ratings remained stable. Baseline predictors of greater self-rated QoL were education, and greater functional ability and relationship quality. Greater proxy-rated QoL was associated with education and greater functional ability, relationship quality, carer social support and carer QoL, lower carer anxiety/depression and less severe neuropsychiatric symptoms in people with dementia. At follow-up, greater self-rated QoL was predicted by greater functional ability, relationship quality, carer social support and having a spousal carer. Greater proxy-rated QoL at follow-up was associated with the same factors as at baseline; however, the dyad living together was an additional predictive factor.Conclusion: Both proxy-ratings and self-ratings of QoL should be interpreted with caution and in the context of each individual caregiving relationship. Different functional, psychosocial, relational and contextual factors influence self- and proxy-ratings, and both sets of factors should be considered in the context of QoL intervention development for the dyad.


Assuntos
Cuidadores/psicologia , Demência/psicologia , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Europa (Continente) , Feminino , Humanos , Vida Independente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Procurador , Inquéritos e Questionários
8.
Animal ; 14(3): 609-616, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31477188

RESUMO

Although the use of local breeds is recommended by organic regulations, breed comparisons performed under organic production conditions with similar production intensities are scarce. Therefore, we compared data of local and widely used Holstein dairy cattle breeds from 2011 to 2015 regarding production, fertility and health from German and Swedish organic farms with similar management intensities within country. In Germany, the energy-corrected total milk yield tended to be lower in the local breed Original Angler Cattle (AAZ, 5193 kg) compared to the modern German Holstein Friesian breed (HO, 5620 kg), but AAZ showed higher milk fat and protein contents (AAZ v. HO: 5.09% v. 4.18% and 3.61% v. 3.31%, respectively). In Sweden, the widely used modern Swedish Holstein (SH) breed had the highest milk yield (9209 kg, fat: 4.10%, protein: 3.31%), while the local Swedish Polled (SKB) showed highest milk fat and protein contents (6169 kg, 4.47%, 3.50%, respectively), followed by the local breed Swedish Red (SRB, 8283 kg, 4.33%, 3.46%, respectively). With regard to fertility characteristics, the German breeds showed no differences, but AAZ tended to have less days open compared to HO (-17 days). In Sweden, breeds did not differ with regard to calving interval, but both local breeds showed a lower number of days open (-10.4 in SRB and -24.1 in SKB compared to SH), and SKB needed fewer inseminations until conception (-0.5 inseminations) compared to SH. Proportion of test day records with a somatic cell count content of ≥100 000 cells per ml milk did not reveal breed differences in any of the two countries. German breeds did not differ regarding the proportion of cows with veterinary treatments. In Sweden, SRB showed the lowest proportion of cows with general veterinary treatment as well as specific treatment due to udder problems (22.8 ± 6.42 and 8.05 ± 2.18, respectively), but the local breed SKB did not differ from SH in either of the two traits. In Sweden, we found no breed differences regarding veterinary treatments due to fertility problems or diagnosis of claw or leg problems during claw trimming. Our results indicate a stronger expression of the antagonism between production and functional traits with increasing production intensity. Future breed comparisons, therefore, need to consider different production intensities within organic farming in order to derive practical recommendations as to how to implement European organic regulations with regard to a suitable choice of breeds.


Assuntos
Cruzamento , Lactação , Animais , Bovinos/genética , Feminino , Alemanha , Leite , Suécia
9.
Z Gerontol Geriatr ; 51(5): 530-536, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28616816

RESUMO

BACKGROUND: People with dementia and their informal carers often do not receive appropriate professional support or it is not received at the right time. OBJECTIVES: Description and comparison of common pathways to formal community dementia care in eight European countries as a part of the transnational Actifcare project. MATERIALS AND METHODS: The German team was responsible for creating an individual case scenario as a starting point. The research teams in Ireland, Italy, the Netherlands, Norway, Portugal, Sweden, and the United Kingdom were then asked to describe a common pathway to formal dementia care by writing their own vignette using the provided individual case scenario. RESULTS: A transnational qualitative content analysis was used to identify the following categories as being the most important: involved professionals, dementia-specific and team-based approaches, proactive roles, and financial aspects. General practitioners (GPs) are described as being the most important profession supporting the access to formal care in all the involved countries. In some countries other professionals take over responsibility for the access procedure. Dementia-specific approaches are rarely part of standard care; team-based approaches have differing significances in each of the countries. Informal carers are mainly proactive in seeking formal care. The Nordic countries demonstrate how financial support enhances access to the professional system. CONCLUSION: Enhanced cooperation between GPs and other professions might optimize access to formal dementia care. Team-based approaches focusing on dementia care should be developed further. Informal carers should be supported and relieved in their role. Financial barriers remain which should be further investigated and reduced.


Assuntos
Cuidadores/psicologia , Demência/terapia , Acessibilidade aos Serviços de Saúde , Adulto , Idoso , Idoso de 80 Anos ou mais , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Qualidade de Vida
10.
J Mol Neurosci ; 60(4): 548-558, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27619521

RESUMO

CD44 is a cell surface adhesion molecule and its principal ligand is hyaluronic acid (HA), a key component of the brain's extracellular matrix. CD44 levels are decreased in the cerebrospinal fluid (CSF) of depressed individuals, and the CD44 gene has been identified in genome wide association study as a possible risk gene in suicidal behavior. In order to define the pathobiological mechanisms by which CD44 may affect behavior, we investigated the role of CD44 using male CD44 knockout (CD44KO) and wild-type mice that underwent chronic mild stress (CMS). Behavior was characterized using the sucrose preference and forced swim tests, open field, novel object recognition, social preference, and the elevated plus maze tests. Gene expression in hippocampus was evaluated using quantitative real-time PCR. Brain monoamines and their metabolites were assessed by high-performance liquid chromatography and serum HA and IL-1ß levels were measured using ELISA and electrochemiluminescence assays. CD44KO mice were more susceptible to stress-induced anxiety-like behavior and displayed increased anhedonia and despair than the wild-type controls. The behavioral phenotype of stressed CD44KO mice was associated with reduced cortical serotonergic and striatal dopaminergic turnover. The hippocampal expression of the receptor for HA-mediated motility (RHAMM) was reduced in the non- stressed CD44KO mice compared with WT mice, in a value similar to that observed in WT mice following exposure to stress. Taken together, our experiments suggest that CD44 plays a key role in stress response in mice.


Assuntos
Ansiedade/genética , Receptores de Hialuronatos/genética , Estresse Psicológico/genética , Animais , Ansiedade/etiologia , Ansiedade/metabolismo , Dopamina/metabolismo , Deleção de Genes , Hipocampo/metabolismo , Hipocampo/fisiologia , Ácido Hialurônico/sangue , Interleucina-1beta/sangue , Masculino , Camundongos , Camundongos Endogâmicos DBA , Fenótipo , Serotonina/metabolismo , Estresse Psicológico/complicações , Estresse Psicológico/metabolismo
11.
Food Chem ; 175: 609-18, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25577126

RESUMO

This study investigated the effect of, and interactions between, contrasting crossbreed genetics (US Brown Swiss [BS] × Improved Braunvieh [BV] × Original Braunvieh [OB]) and feeding regimes (especially grazing intake and pasture type) on milk fatty acid (FA) profiles. Concentrations of total polyunsaturated FAs, total omega-3 FAs and trans palmitoleic, vaccenic, α-linolenic, eicosapentaenoic and docosapentaenoic acids were higher in cows with a low proportion of BS genetics. Highest concentrations of the nutritionally desirable FAs, trans palmitoleic, vaccenic and eicosapentaenoic acids were found for cows with a low proportion of BS genetics (0-24% and/or 25-49%) on high grazing intake (75-100% of dry matter intake) diets. Multivariate analysis indicated that the proportion of OB genetics is a positive driver for nutritionally desirable monounsaturated and polyunsaturated FAs while BS genetics proportion was positive driver for total and undesirable individual saturated FAs. Significant genetics × feeding regime interactions were also detected for a range of FAs.


Assuntos
Bovinos/genética , Indústria de Laticínios/métodos , Leite/química , Ração Animal , Animais , Ácidos Graxos/análise , Ácidos Graxos Ômega-3/análise , Feminino , Pradaria , Hibridização Genética
12.
Animal ; 8(12): 1971-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25076185

RESUMO

Body condition scoring is a common tool to assess the subcutaneous fat reserves of dairy cows. Because of its subjectivity, which causes limits in repeatability, it is often discussed controversially. Aim of the current study was to evaluate the impact of considering the cows overall appearance on the scoring process and on the validity of the results. Therefore, two different methods to reveal body condition scores (BCS), 'independent BCS' (iBCS) and 'dependent BCS' (dBCS), were used to assess 1111 Swiss Brown Cattle. The iBCS and the dBCS systems were both working with the same flowchart with a decision tree structure for visual and palpatory assessment using a scale from 2 to 5 with increment units of 0.25. The iBCS was created strictly complying with the defined frames of the decision tree structure. The system was chosen due to its formularized approach to reduce the influence of subjective impressions. By contrast, the dBCS system, which was in line with common practice, had a more open approach, where - besides the decision tree - the overall impression of the cow's physical appearance was taken into account for generating the final score. Ultrasound measurement of the back fat thickness (BFT) was applied as a validation method. The dBCS turned out to be the better predictor of BFT, explaining 67.3% of the variance. The iBCS was only able to explain 47.3% of the BFT variance. Within the whole data set, only 31.3% of the animals received identical dBCS and iBCS. The pin bone region caused the most deviations between dBCS and iBCS, but also assessing the pelvis line, the hook bones and the ligaments led to divergences in around 20% of the scored animals. The study showed that during the assessment of body condition a strict adherence to a decision tree is a possible source of inexact classifications. Some body regions, especially the pin bones, proved to be particularly challenging for scoring due to difficulties in assessing them. All the more, the inclusion of the overall appearance of the cow into the assessment process counteracted these errors and led to a fair predictability of BFT with the flowchart-based BCS. This might be particularly important, if different cattle types and breeds are assessed.


Assuntos
Composição Corporal/fisiologia , Bovinos/fisiologia , Animais , Feminino , Gordura Subcutânea
13.
J Dairy Sci ; 97(3): 1774-81, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24440263

RESUMO

In this study, direct genomic values for the functional traits general temperament, milking temperament, aggressiveness, rank order in herd, milking speed, udder depth, position of labia, and days to first heat in Brown Swiss dairy cattle were estimated based on ~777,000 (777 K) single nucleotide polymorphism (SNP) information from 1,126 animals. Accuracy of direct genomic values was assessed by a 5-fold cross-validation with 10 replicates. Correlations between deregressed proofs and direct genomic values were 0.63 for general temperament, 0.73 for milking temperament, 0.69 for aggressiveness, 0.65 for rank order in herd, 0.69 for milking speed, 0.71 for udder depth, 0.66 for position of labia, and 0.74 for days to first heat. Using the information of ~54,000 (54K) SNP led to only marginal deviations in the observed accuracy. Trying to predict the 20% youngest bulls led to correlations of 0.55, 0.77, 0.73, 0.55, 0.64, 0.59, 0.67, and 0.77, respectively, for the traits listed above. Using a novel method to estimate the accuracy of a direct genomic value (defined as correlation between direct genomic value and true breeding value and accounting for the correlation between direct genomic values and conventional breeding values) revealed accuracies of 0.37, 0.20, 0.19, 0.27, 0.48, 0.45, 0.36, and 0.12, respectively, for the traits listed above. These values are much smaller but probably also more realistic than accuracies based on correlations, given the heritabilities and samples sizes in this study. Annotation of the largest estimated SNP effects revealed 2 candidate genes affecting the traits general temperament and days to first heat.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios , Estudo de Associação Genômica Ampla/veterinária , Genoma , Polimorfismo de Nucleotídeo Único , Animais , Cruzamento , Bovinos/genética , Feminino , Masculino , Reprodutibilidade dos Testes , Temperamento
14.
J Dairy Sci ; 96(9): 5965-76, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23871376

RESUMO

The aim of this study was to estimate genetic parameters and accuracies of breeding values for milk content traits of individual udder quarters in Brown Swiss cattle. Data of 1,799 phenotyped cows from 40 Swiss dairy herds were analyzed, taking the complete pedigree into account. Fat, protein, lactose, and urea contents, somatic cell score (SCS), and information about hyperkeratosis were available for each udder quarter. The milk of rear udder quarters was found to have significantly higher lactose content and significantly lower fat content than milk of the front udder quarters. The same trend found for fat content was observed for protein content, whereas no differences between the udder quarters were observed for urea content, SCS, or hyperkeratosis. Heritabilities for each udder quarter were in the following ranges: fat content 0.09±0.06 to 0.14±0.06, protein content 0.20±0.09 to 0.33±0.07, lactose content 0.04±0.03 to 0.16±0.07, urea content 0.13±0.07 to 0.22±0.08, SCS 0.18±0.06 to 0.32±0.07, and hyperkeratosis 0.12±0.04 to 0.26±0.05. In our study, hyperkeratosis, protein content, and SCS showed higher heritabilities in the front udder quarters, fat content had higher heritabilities in the rear udder quarters, and no systematic pattern in heritability was observed for lactose content or urea content. Additive genetic correlations between all udder quarters were >0.90 for protein and urea contents, whereas they were remarkably low (<0.60) for SCS. For fat and lactose contents, the genetic correlations between the 2 front or between the 2 rear quarters, respectively, were notably higher than correlations between 1 front and 1 rear quarter, suggesting that the front and the rear udders could be considered as partly genetically different organs. The variability within the udder as such was found to be of low heritability (<0.10) in general, but repeatability was moderate to high for some traits (lactose content: 0.33±0.05, protein content: 0.53±0.05). Some of these findings can be explained by differences in the physiological background of the traits.


Assuntos
Bovinos/genética , Glândulas Mamárias Animais/anatomia & histologia , Característica Quantitativa Herdável , Animais , Bovinos/anatomia & histologia , Contagem de Células/veterinária , Gorduras/análise , Feminino , Lactação/genética , Lactose/análise , Leite/química , Leite/citologia , Proteínas do Leite/análise , Fenótipo , Ureia/análise
15.
J Dairy Sci ; 96(9): 5954-64, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23871377

RESUMO

The aim of this study was to estimate genetic parameters and accuracies of breeding values for a set of functional, behavior, and conformation traits in Brown Swiss cattle. These traits were milking speed, udder depth, position of labia, rank order in herd, general temperament, aggressiveness, milking temperament, and days to first heat. Data of 1,799 phenotyped Brown Swiss cows from 40 Swiss dairy herds were analyzed taking the complete pedigree into account. Estimated heritabilities were within the ranges reported in literature, with results at the high end of the reported values for some traits (e.g., milking speed: 0.42±0.06, udder depth: 0.42±0.06), whereas other traits were of low heritability and heritability estimates were of low accuracy (e.g., milking temperament: 0.04±0.04, days to first heat: 0.02±0.04). For most behavior traits, we found relatively high heritabilities (general temperament: 0.38±0.07, aggressiveness: 0.12±0.08, and rank order in herd: 0.16±0.06). Position of labia, arguably an indicator trait for pathological urovagina, was genetically analyzed in this study for the first time, and a moderate heritability (0.28±0.06) was estimated.


Assuntos
Bovinos/genética , Característica Quantitativa Herdável , Animais , Bovinos/anatomia & histologia , Feminino , Lactação/genética , Glândulas Mamárias Animais/anatomia & histologia , Gravidez/genética , Fatores de Tempo
16.
Neotrop Entomol ; 40(5): 542-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22068939

RESUMO

The search for factors shaping leaf-litter ant communities has received particular attention due to the essential role of these insects in many ecological processes. Here, we aimed to investigate how the number of leaves and leaf morphotypes affect the litter-ant species density at forest edge and interior in an Atlantic Forest remnant in the state of Alagoas, Brazil. This study was developed based on 28 litter plots (1m² each), 14 in the forest interior and 14 in the forest edge. As we early expected, ant species density increased with increasing both the number of leaves and the number of leaf morphotypes, but this result was clearly influenced by plot location. Contrasting with the forest interior, ant species density did not increase as the number of leaves increased in the forest edge. Possibly, factors such as plant species richness, vegetation structure and environmental conditions affect ant species density as well as promote a patchy distribution of species in ant communities along the edge-to-interior gradient. Our findings suggest that edge-affected forests present more simplified ant communities, with different factors shaping its structure. We encourage future studies to include leaf litter heterogeneity as one of the explanatory variables investigated.


Assuntos
Formigas , Ecossistema , Folhas de Planta , Animais , Formigas/classificação , Brasil , Solo
17.
Curr Top Microbiol Immunol ; 318: 177-92, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18219818

RESUMO

Myelin repair (remyelination) following the demyelination of central nervous system (CNS) axons in diseases such as multiple sclerosis plays a critical role in determining the level of accompanying neurologic disability. While remyelination can be quite robust, in multiple sclerosis it often fails. Understanding and stimulating the remyelination process are therefore important goals in MS research. Remyelination is a complex cellular process that involves an intimate interplay between the myelin-producing cells of the CNS (oligodendrocytes), the axons to be myelinated, as well as CNS-infiltrating immune cells. Genetic analysis can be a powerful tool for the functional analysis of complex cellular processes and has recently been applied to the problem of remyelination failure during disease. This chapter reviews the recent use of genetic approaches for the study of CNS remyelination in mouse models of demyelinating disease.


Assuntos
Doenças do Sistema Nervoso Central/genética , Doenças do Sistema Nervoso Central/patologia , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/patologia , Bainha de Mielina/fisiologia , Regeneração Nervosa/fisiologia , Animais , Infecções por Cardiovirus/genética , Infecções por Cardiovirus/patologia , Infecções por Cardiovirus/fisiopatologia , Doenças do Sistema Nervoso Central/fisiopatologia , Doenças Desmielinizantes/fisiopatologia , Modelos Animais de Doenças , Humanos , Camundongos , Bainha de Mielina/patologia , Theilovirus
18.
Int MS J ; 11(3): 95-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15585167

RESUMO

There are two main animal model systems currently used to study MS: experimental autoimmune/allergic encephalomyelitis (EAE) and experimental viral infection, including the Theiler's murine encephalomyelitis virus (TMEV). Both models have led to a greater understanding of MS and the development of clinical therapies. These systems have allowed in-depth study of the immune system and inflammatory mechanisms potentially involved in MS pathophysiology. Analysing therapeutic successes and failures with both models may also help the development of more directed, positive treatments for MS that have fewer negative effects.


Assuntos
Modelos Animais de Doenças , Esclerose Múltipla/patologia , Animais , Axônios/patologia , Encefalomielite Autoimune Experimental/complicações , Camundongos , Esclerose Múltipla/etiologia , Theilovirus/patogenicidade
19.
J Allergy Clin Immunol ; 108(4 Suppl): S121-5, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11586279

RESUMO

Our view of the immune system continues to evolve from a system dedicated primarily to defense against pathogens to a system that monitors the integrity of the organism and aids in repair following damage. Repair following injury to the central nervous system (CNS) is facilitated by both cellular and humoral components of the immune system. Transfer of macrophages or T cells activated against CNS antigens promote axon regrowth and protect axons from further damage. Animals immunized with spinal cord antigens and subsequently challenged with demyelination or transection of the spinal cord demonstrate better repair than animals without prior immunization. In both experimental systems, antibodies are the biologically active immune component. Human mAbs reactive to oligodendrocytes that arise in the absence of neurologic injury promote remyelination. These data support the hypothesis that B-cell clones producing mAbs reactive to CNS epitopes are a normal part of the human antibody repertoire. They challenge the assertion that an immune response to CNS antigens is pathogenic. Treatment with CNS-reactive human mAbs following CNS disease may facilitate CNS regeneration.


Assuntos
Doenças do Sistema Nervoso Central/terapia , Sistema Nervoso Central/imunologia , Adjuvantes Imunológicos/uso terapêutico , Animais , Anticorpos Monoclonais/uso terapêutico , Encefalomielite/terapia , Camundongos , Esclerose Múltipla/terapia
20.
Proc Natl Acad Sci U S A ; 98(20): 11205-10, 2001 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-11562501

RESUMO

Previously, we demonstrated that a protein from Xenopus egg jelly exhibits sperm chemoattractant activity when assayed by either video microscopy or by sperm passage across a porous filter. Here we describe the isolation and purification of allurin, the protein responsible for this activity. Freshly oviposited jellied eggs were soaked in buffer, and the conditioned medium was loaded onto an anion exchange column and eluted with an NaCl gradient. The active fraction was purified further by RP-HPLC, the chemoattractant protein appearing as a single sharp peak. The amino acid sequence of the protein, determined by direct sequencing and cloning of cDNAs coding for the protein, consisted of 184 amino acids having a molecular mass of 21,073 Da. The protein shares homology with the mammalian cysteine-rich secretory protein (CRISP) family that includes testes-specific spermatocyte protein 1, a cell adhesion protein which links spermatocytes to Seritoli cells, and acidic epididymal glycoproteins that bind to sperm and have been implicated in sperm-egg fusion. Phylogenetic analysis suggests that allurin evolved from the ancestral protein that gave rise to the mammalian CRISP family. Addition of allurin to this family portends that the CRISP family represents a group of "sperm escort" proteins, which bind to sperm at various steps in their life history, facilitating passage from one functional stage to the next. Allurin stands out in this regard, representing both the first vertebrate sperm chemoattractant to be purified and sequenced and the first member of the CRISP family to be found in the female reproductive tract.


Assuntos
Proteínas de Transporte/química , Proteínas de Transporte/fisiologia , Fatores Quimiotáticos/química , Fatores Quimiotáticos/fisiologia , Proteínas do Ovo/química , Proteínas do Ovo/fisiologia , Oócitos/fisiologia , Proteínas de Plasma Seminal , Espermatozoides/fisiologia , Sequência de Aminoácidos , Animais , Feminino , Humanos , Masculino , Mamíferos , Camundongos , Dados de Sequência Molecular , Peso Molecular , Filogenia , Ratos , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Interações Espermatozoide-Óvulo , Xenopus laevis
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