44 research outputs found
Odd-skipped genes specify the signaling center that triggers retinogenesis in Drosophila
5 páginas, 4 figuras.Although many of the factors responsible for conferring identity to the eye field in Drosophila have been identified, much less is known about how the expression of the retinal `trigger', the signaling molecule Hedgehog, is controlled. Here, we show that the co-expression of the conserved odd-skipped family genes at the posterior margin of the eye field is required to activate hedgehog expression and thereby the onset of retinogenesis. The fly Wnt1 homologue wingless represses the odd-skipped genes drm and odd along the anterior margin and, in this manner, spatially restricts the extent of retinal differentiation within the eye field.This work has been funded through grants BMC2003-06248 (Ministerio de Educación y Ciencia, Spain) and POCTI/BIA-BCM/56043/2004 [Fundação para a Ciência e a Tecnologia (FCT), Portugal], which are co-funded by FEDER, to F.C. C.B-P. and J.B. are funded by FCT.Peer reviewe
Распределение радионуклидов и минералов в гранулометрических фракциях луговых почв припортального участка штольни №176 испытательной площадки "Дегелен" СИП
Estradiol reverses excitatory synapse loss in a cellular model of neuropsychiatric disorders
Loss of glutamatergic synapses is thought to be a key cellular pathology associated with neuropsychiatric disorders including schizophrenia (SCZ) and major depressive disorder (MDD). Genetic and cellular studies of SCZ and MDD using in vivo and in vitro systems have supported a key role for dysfunction of excitatory synapses in the pathophysiology of these disorders. Recent clinical studies have demonstrated that the estrogen, 17β-estradiol can ameliorate many of the symptoms experienced by patients. Yet, to date, our understanding of how 17β-estradiol exerted these beneficial effects is limited. In this study, we have tested the hypothesis that 17β-estradiol can restore dendritic spine number in a cellular model that recapitulates the loss of synapses associated with SCZ and MDD. Ectopic expression of wildtype, mutant or shRNA-mediated knockdown of Disrupted in Schizophrenia 1 (DISC1) reduced dendritic spine density in primary cortical neurons. Acute or chronic treatment with 17β-estradiol increased spine density to control levels in neurons with altered DISC1 levels. In addition, 17β-estradiol reduced the extent to which ectopic wildtype and mutant DISC1 aggregated. Furthermore, 17β-estradiol also caused the enrichment of synaptic proteins at synapses and increased the number of dendritic spines containing PSD-95 or that overlapped with the pre-synaptic marker bassoon. Taken together, our data indicates that estrogens can restore lost excitatory synapses caused by altered DISC1 expression, potentially through the trafficking of DISC1 and its interacting partners. These data highlight the possibility that estrogens exert their beneficial effects in SCZ and MDD in part by modulating dendritic spine number
PLASTICS IN THE ANTARCTIC ENVIRONMENT: ARE WE LOOKING ONLY AT THE TIP OF THE ICEBERG?
The available literature on marine debris and its impacts in the sub-Antarctic Islands, the Antarctic Peninsula and on the coasts of Antarctica was organized and interpreted here. A total of 98 documents covering from 1982 to 2010 were found and 95% had their full contents accessed. Seventy documents were on line scientific abstracts from the Commission on the Conservation of Antarctic Marine Living Resources (CCAMLR). The occurrence of marine debris in the Antarctic environment, fur seals entanglement in marine debris, interactions between seabirds and marine debris and long range transport of benthos on floating plastics were the main issues discussed. Fishing operations in the Southern Ocean were identified as the major source of marine debris, but according to the type of debris reported, plastics from lower latitudes may also cross the Polar Front (PF). Possible links between Antarctic and South America, the closest intercontinental connection, in relation to plastic marine debris pollution are highlighted. As reported for lower latitudinal gradients, plastic pollution is an important problem to the Antarctic environment. However, specific and detailed works are necessary since our current knowledge probably expose only a small part of the real problem. Concerning this sort of pollution in the Antarctic marine and coastal environments, we may be looking solely at the tip of iceberg.PLÁSTICOS EN EL ECOSISTEMA ANTÁRTICO: ¿SERÁ QUE ESTAMOS VIENDO SOLAMENTE LA PUNTA DEL ICEBERG? En este trabajo fue organizada y interpretada la literatura científica relacionada con la presencia y los impactos de basura marina en islas sub-antárticas, en la Península Antártica y en la costa del continente Antártico. Fueron encontrados un total de 98 documentos, publicados entre 1982 e 2010, de los cuales se tuvo acceso a la totalidad del documento en el 95% de los casos. Setenta documentos son resúmenes científicos de la Comisión para la Conservación de los Recursos Marinos en la Antártica (CCAMLR, en inglés) disponibles para consulta en internet. La ocurrencia de basura marina en el ecosistema Antártico (principalmente en playas arenosas), el enredamiento de lobos marinos en diferentes ítems de basura, interacciones (ingestión, enredamiento y ocurrencia de basura en áreas de nidificación) entre aves marinas y la basura, y el transporte de organismos bentónicos en plásticos flotantes fueron los asuntos más abordados en los documentos analizados. Operaciones de pesca en el Océano Atlántico Sur fueron identificadas como la mayor fuente de basura para el ambiente, pero plásticos originados en menores latitudes también fueron identificados, indicando transporte a través del Frente Polar (PF, en inglés). También se abordan y se discuten en este trabajo, posibles links entre la Antártica y América del Sul, la conexión más próxima intercontinental, en relación a la contaminación por plásticos. Como es reportado para gradientes latitudinales menores, la contaminación por plásticos es un problema relevante para el ecosistema Antártico. Sin embargo, estudios más específicos y detallados son necesarios ya que el conocimiento actual representa, probablemente, solo una pequeña parte del verdadero problema. En relación a este tipo de contaminación en los ambientes marinos y costeros del ecosistema Antártico, posiblemente estamos viendo solo la punta del iceberg. Palabras clave: Especies exóticas; A. gazella; Procellariiformes; hilos de nylon; fragmentos plásticos.PLÁSTICOS NO ECOSSISTEMA ANTÁRTICO: SERÁ QUE ESTAMOS VENDO SOMENTE A PONTA DO ICEBERG? A literatura científica relacionada à presença e aos impactos do lixo marinho em Ilhas Sub-Antárticas, na Península Antártica e na costa do continente Antártico foi organizada e interpretada neste trabalho. Um total de 98 documentos, publicados entre 1982 e 2010, foi encontrado e 95% tiveram seu conteúdo acessado integralmente. Setenta documentos são resumos científicos da Comissão para a Conservação dos Recursos Marinhos na Antártica (CCAMLR, em inglês) disponíveis para consulta na internet. A ocorrência de lixo marinho no ecossistema Antártico (principalmente praias arenosas), o enredamento de lobos marinhos em itens do lixo, interações (ingestão, enredamento e ocorrência de lixo em áreas de nidificação) entre aves marinhas e o lixo, e o transporte de organismos bentônicos em plásticos flutuantes foram os assuntos mais abordados nos documentos analisados. Operações de pesca no Oceano Atlântico Sul foram identificadas como a maior fonte de lixo para o ambiente, mas plásticos originados em menores latitudes também foram identificados, indicando transporte através da Frente Polar (PF, em inglês). Possíveis links entre a Antárticae a América do Sul, a mais próxima conexão intercontinental, em relação à poluição por plásticos também estão destacados e discutidos neste trabalho. Como reportado para menores gradientes latitudinais, a poluição por plásticos é um problema relevante para o ecossistema Antártico. Entretanto, estudos mais específicos e detalhados são necessários já que o conhecimento atual representa, provavelmente, só uma pequena parte do verdadeiro problema. Em relação a este tipo de poluição nos ambientes marinhos e costeiros do ecossistema Antártico, nós estamos possivelmente vendo somente a ponta do iceberg. Palavras-chave: Espécies exóticas; A. gazella; Procellariiformes; linhas de nylon; fragmentos plásticos
Evaluation of the productivity, content and nutrient use efficiency in genotypes of Eucalyptus spp. in Jequitinhonha valley, MG
A hibrida\ue7\ue3o de esp\ue9cies de eucalipto possibilita a
obten\ue7\ue3o de h\uedbridos mais produtivos e com alta
efici\ueancia de absor\ue7\ue3o e/ou utiliza\ue7\ue3o de
nutrientes, dependendo das esp\ue9cies combinadas. Neste contexto, o
presente trabalho, conduzido na regi\ue3o do Vale do Jequitinhonha,
Minas Gerais, teve por objetivos: determinar a produtividade, o
conte\ufado e a efici\ueancia de utiliza\ue7\ue3o de N, P, K,
Ca e Mg de h\uedbridos interespec\uedficos de Eucalyptus spp.
Para tanto, mediu-se o di\ue2metro \ue0 altura do peito (DAP) de
todas as \ue1rvores presentes em cada parcela, e abateram-se
tr\ueas \ue1rvores com di\ue2metro correspondente ao da
\ue1rvore m\ue9dia. Procedeu-se \ue0 cubagem das \ue1rvores
pelo m\ue9todo de Smallian, utilizando a altura, o di\ue2metro e a
espessura de casca na base e a 25, 50, 75 e 100 % da altura comercial.
O peso de material fresco do lenho, da casca, das folhas e dos galhos
foi determinado no campo, e desses componentes se coletaram amostras
para determina\ue7\ue3o do peso da mat\ue9ria seca. As amostras
do tronco consistiram de discos coletados, com casca, na base e a 25,
50, 75 e 100% da altura comercial. As amostras de tecido vegetal foram
analisadas para: N, P, K, Ca e Mg. Os resultados obtidos n\ue3o
indicaram diferen\ue7as significativas para a produ\ue7\ue3o de
biomassa de copa entre os h\uedbridos de eucalipto em
conseq\ufc\ueancia de apresentarem mesma idade. Entretanto, a
produ\ue7\ue3o de biomassa de tronco apresentou diferen\ue7as
significativas sendo os h\uedbridos de Eucalyptus urophylla S. T.
Blake proveniente de poliniza\ue7\ue3o natural mais produtivo em 50
e 69% em compara\ue7\ue3o aos h\uedbridos de Eucalyptus urophylla
W. Hill. Ex Maiden com Eucalyptus grandis Dehnh.e de Eucalyptus
urophylla com descendentes do cruzamento de Eucalyptus camaldulensis
com Eucalyptus grandis respectivamente. Al\ue9m disso, aqueles
h\uedbridos foram os que alocaram maior quantidade de biomassa no
tronco (92,3%) em rela\ue7\ue3o \ue0 copa (7,7%), e ainda foram
os mais eficientes na absor\ue7\ue3o e utiliza\ue7\ue3o de N,
P, K, Ca e Mg. Concluiu-se que: 1) h\uedbridos de Eucalyptus
urophylla provenientes de poliniza\ue7\ue3o natural ou controlada
n\ue3o apresentam diferen\ue7a na produ\ue7\ue3o de biomassa de
copa quando avaliados numa mesma idade; 2) a poliniza\ue7\ue3o
controlada de Eucalyptus urophylla com Eucalyptus grandis e com
descendentes do cruzamento de Eucalyptus camaldulensis com Eucalyptus
grandis reduz a produ\ue7\ue3o de biomassa de tronco; 3)
h\uedbridos de Eucalyptus urophylla provenientes de
poliniza\ue7\ue3o natural s\ue3o mais produtivos e mais
eficientes na absor\ue7\ue3o e utiliza\ue7\ue3o de N, P, K, Ca
e Mg e 4) h\uedbridos de Eucalyptus urophylla provenientes de
descendentes do cruzamento de Eucalyptus camaldulensis com Eucalyptus
grandis s\ue3o menos produtivos e menos eficientes na
absor\ue7\ue3o e utiliza\ue7\ue3o de N, P, K, Ca e Mg.The hybridization of eucalyptus species can provide more productive
hybrids and with a high efficiency of nutrient absorption and, or,
nutrient use, depending on the combined species. In this context, the
present work was undertaken in the Jequitinhonha Valley region, Minas
Gerais, and its objectives were: to determine the productivity, content
and use efficiency of N, P, K, Ca and Mg in interspecific hybrids of
Eucalyptus spp. In each plot, the diameters were measured at breast
height (DBH) in all the trees, and three trees with diameter similar to
the average mean were felled. The volume of the trees was estimated by
the Smallian method, using the height, diameter and the bark thickness
at the base and at 25, 50, 75 and 100 % of the commercial height. The
fresh weight of the wood, bark, leaves and branches was determined in
the field, and samples from them were collected for the determination
of dry matter. The log samples consisted of collected disks with bark,
from the base and at 25, 50, 75 and 100 % of the commercial height. The
samples of vegetable tissues were analyzed for: N, P, K, Ca and Mg. The
results obtained did not show significant differences for the
production of crown biomass between the eucalyptus hybrids of the same
age. However, the production of log biomass presented significant
differences and the naturally pollinated hybrids of Eucalyptus
urophylla were 50.0 % and 69.0 % more productive compared with the
hybrids of Eucalyptus urophylla with Eucalyptus grandis and
Eucalyptus urophylla with descendants of the crossing of Eucalyptus
camaldulensis with Eucalyptus grandis, respectively. Also, these
hybrids allocated larger amount of biomass in the log (92.3 %) in
relation to the crown (7.7 %), and they were more efficient in the
absorption and use of N, P, K, Ca and Mg. The conclusions were that: 1)
same aged hybrids of Eucalyptus urophylla from natural or controlled
pollinations did not differ in their crown biomass; 2) log biomass was
reduced in the hybrids from controlled pollination between Eucalyptus
urophylla with Eucalyptus grandis and Eucalyptus urophylla with
descendants of the crossing of Eucalyptus camaldulensis with
Eucalyptus grandis; 3) hybrids of Eucalyptus urophylla from natural
pollination were more productive and more efficient in the absorption
and efficiency of use of N, P, K, Ca and Mg and 4) hybrids of
Eucalyptus urophylla with descendants of the crossing of Eucalyptus
camaldulensis with Eucalyptus grandis are less productive and less
efficient in the absorption and use of N, P, K, Ca and Mg
Cost-effectiveness of an integrated 'fast track' rehabilitation service for multi-trauma patients involving dedicated early rehabilitation intervention programs: design of a prospective, multi-centre, non-randomised clinical trial
Contains fulltext :
79649.pdf (publisher's version ) (Open Access)ABSTRACT: BACKGROUND: In conventional multi-trauma care service (CTCS), patients are admitted to hospital via the accident & emergency room. After surgery they are transferred to the IC-unit followed by the general surgery ward. Ensuing treatment takes place in a hospital's outpatient clinic, a rehabilitation centre, a nursing home or the community. Typically, each of the CTCS partners may have its own more or less autonomous treatment perspective. Clinical evidence, however, suggests that an integrated multi-trauma rehabilitation approach ('Supported Fast-track multi-Trauma Rehabilitation Service': SFTRS), featuring: 1) earlier transfer to a specialised trauma rehabilitation unit; 2) earlier start of 'non-weight-bearing' training and multidisciplinary treatment; 3) well-documented treatment protocols; 4) early individual goal-setting; 5) co-ordination of treatment between trauma surgeon and physiatrist, and 6) shorter lengths-of-stay, may be more (cost-)effective.This paper describes the design of a prospective cohort study evaluating the (cost-) effectiveness of SFTRS relative to CTCS. METHODS/DESIGN: The study population includes multi-trauma patients, admitted to one of the participating hospitals, with an Injury Severity Scale score > = 16, complex multiple injuries in several extremities or complex pelvic and/or acetabulum fractures. In a prospective cohort study CTCS and SFTRS will be contrasted. The inclusion period is 19 months. The duration of follow-up is 12 months, with measurements taken at baseline, and at 3,6,9 and 12 months post-injury.Primary outcome measures are 'quality of life' (SF-36) and 'functional health status' (Functional Independence Measure). Secondary outcome measures are the Hospital Anxiety & Depression Scale, the Mini-Mental State Examination as an indicator of cognitive functioning, and the Canadian Occupational Performance Measure measuring the extent to which individual ADL treatment goals are met. Costs will be assessed using the PROductivity and DISease Questionnaire and a cost questionnaire. DISCUSSION: The study will yield results on the efficiency of an adapted care service for multi-trauma patients (SFTRS) featuring earlier (and condensed) involvement of specialised rehabilitation treatment. Results will show whether improved SFTRS logistics, combined with shorter stays in hospital and rehabilitation clinic and specialised early rehabilitation training modules are more (cost-) effective, relative to CTCS. TRIAL REGISTRATION: Current Controlled Trials register (ISRCTN68246661) and Netherlands Trial Register (NTR139)
Surface pretreatments for medical application of adhesion
Medical implants and prostheses (artificial hips, tendono- and ligament plasties) usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m). This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body
Single nucleus genome sequencing reveals high similarity among nuclei of an endomycorrhizal fungus
Nuclei of arbuscular endomycorrhizal fungi have been described as highly diverse due to their asexual nature and absence of a single cell stage with only one nucleus. This has raised fundamental questions concerning speciation, selection and transmission of the genetic make-up to next generations. Although this concept has become textbook knowledge, it is only based on studying a few loci, including 45S rDNA. To provide a more comprehensive insight into the genetic makeup of arbuscular endomycorrhizal fungi, we applied de novo genome sequencing of individual nuclei of Rhizophagus irregularis. This revealed a surprisingly low level of polymorphism between nuclei. In contrast, within a nucleus, the 45S rDNA repeat unit turned out to be highly diverged. This finding demystifies a long-lasting hypothesis on the complex genetic makeup of arbuscular endomycorrhizal fungi. Subsequent genome assembly resulted in the first draft reference genome sequence of an arbuscular endomycorrhizal fungus. Its length is 141 Mbps, representing over 27,000 protein-coding gene models. We used the genomic sequence to reinvestigate the phylogenetic relationships of Rhizophagus irregularis with other fungal phyla. This unambiguously demonstrated that Glomeromycota are more closely related to Mucoromycotina than to its postulated sister Dikarya