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1.
Plant Cell Environ ; 41(6): 1311-1330, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29385242

RESUMO

Although the physiological consequences of plant growth under saline conditions have been well described, understanding the core mechanisms conferring plant salt adaptation has only started. We target the root plasma membrane proteomes of two barley varieties, cvs. Steptoe and Morex, with contrasting salinity tolerance. In total, 588 plasma membrane proteins were identified by mass spectrometry, of which 182 were either cultivar or salinity stress responsive. Three candidate proteins with increased abundance in the tolerant cv. Morex were involved either in sterol binding (a GTPase-activating protein for the adenosine diphosphate ribosylation factor [ZIGA2], and a membrane steroid binding protein [MSBP]) or in phospholipid synthesis (phosphoethanolamine methyltransferase [PEAMT]). Overexpression of barley MSBP conferred salinity tolerance to yeast cells, whereas the knock-out of the heterologous AtMSBP1 increased salt sensitivity in Arabidopsis. Atmsbp1 plants showed a reduced number of lateral roots under salinity, and root-tip-specific expression of barley MSBP in Atmsbp1 complemented this phenotype. In barley, an increased abundance of MSBP correlates with reduced root length and lateral root formation as well as increased levels of auxin under salinity being stronger in the tolerant cv. Morex. Hence, we concluded the involvement of MSBP in phytohormone-directed adaptation of root architecture in response to salinity.


Assuntos
Membrana Celular/metabolismo , Hordeum/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/anatomia & histologia , Proteoma/metabolismo , Proteômica/métodos , Salinidade , Ácido Abscísico/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Cromatografia de Fase Reversa , Genótipo , Hordeum/efeitos dos fármacos , Hordeum/fisiologia , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Sesquiterpenos/metabolismo , Cloreto de Sódio/farmacologia , Esteroides/metabolismo , Estresse Fisiológico/efeitos dos fármacos
2.
J Neurosci ; 32(9): 2915-30, 2012 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-22378867

RESUMO

The common neurotransmitter serotonin controls different aspects of early neuronal differentiation, although the underlying mechanisms are poorly understood. Here we report that activation of the serotonin 5-HT(7) receptor promotes synaptogenesis and enhances synaptic activity in hippocampal neurons at early postnatal stages. An analysis of Gα(12)-deficient mice reveals a critical role of G(12)-protein for 5-HT(7) receptor-mediated effects in neurons. In organotypic preparations from the hippocampus of juvenile mice, stimulation of 5-HT(7)R/G(12) signaling potentiates formation of dendritic spines, increases neuronal excitability, and modulates synaptic plasticity. In contrast, in older neuronal preparations, morphogenetic and synaptogenic effects of 5-HT(7)/G(12) signaling are abolished. Moreover, inhibition of 5-HT(7) receptor had no effect on synaptic plasticity in hippocampus of adult animals. Expression analysis reveals that the production of 5-HT(7) and Gα(12)-proteins in the hippocampus undergoes strong regulation with a pronounced transient increase during early postnatal stages. Thus, regulated expression of 5-HT(7) receptor and Gα(12)-protein may represent a molecular mechanism by which serotonin specifically modulates formation of initial neuronal networks during early postnatal development.


Assuntos
Envelhecimento/genética , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/fisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Neurogênese/genética , Neurônios/fisiologia , Receptores de Serotonina/fisiologia , Transdução de Sinais/genética , Animais , Animais Recém-Nascidos , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/biossíntese , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/genética , Hipocampo/crescimento & desenvolvimento , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Receptores de Serotonina/biossíntese , Receptores de Serotonina/genética , Sinapses/genética
3.
J Neurophysiol ; 106(3): 1500-14, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21697440

RESUMO

During early development neuronal networks express slow oscillating synchronized activity. The activity can be driven by several, not necessarily mutually exclusive, mechanisms. Each mechanism might have distinctive consequences for the phenomenology, formation, or sustainment of the early activity pattern. Here we study the emergence of the oscillatory activity in three computational models and multisite extracellular recordings that we obtained from developing cortical networks in vitro. The modeled networks consist of leaky integrate-and-fire neurons with adaptation coupled via depressing synapses, which were driven by neurons that are intrinsically bursting, intrinsically random spiking, or driven by spontaneous synaptic activity. The activity of model networks driven by intrinsically bursting cells best matched the phenomenology of 1-wk-old cultures, in which early oscillatory activity has just begun. Intrinsically bursting neurons were present in cortical cultures, but we found them only in those cultures that were younger than 3 wk in vitro. On the other hand, synaptically dependent random spiking was highest after 3 wk in vitro. In conclusion, model networks driven by intrinsically bursting cells show a good approximation of the emergent recurrent population activity in young networks, whereas the activity of more mature networks seems to be better explained by spontaneous synaptic activity. Moreover, similar to previous experimental observations, distributed stimulation in the model was more effective in suppressing population bursts than repeated stimulation of the same neurons. This observation can be explained by an effective depression of a larger fraction of synapses by distributed stimulation.


Assuntos
Relógios Biológicos , Córtex Cerebral , Redes Neurais de Computação , Relógios Biológicos/fisiologia , Córtex Cerebral/crescimento & desenvolvimento , Potenciais Pós-Sinápticos Excitadores/fisiologia , Distribuição Aleatória , Potenciais Sinápticos/fisiologia
4.
Polymers (Basel) ; 13(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34883739

RESUMO

This study identifies the importance of reducing press times by employing high-frequency pressing of spruce-laminated timber bound with sustainable casein adhesives. Spruce lamellas with dimensions of 12 × 10 × 75 cm were bonded into five-layered laminated timber and then separated into single-layer solid wood panels. Three types of casein (acid casein from two sources and rennin) were used. To compare the effectiveness of the casein formulation, two control samples bonded with polyvinyl acetate (PVAc) adhesive were pressed at room temperature (20 °C) and also with high-frequency equipment. The tests included compression shear strength, modulus of rupture, modulus of elasticity and screw withdrawal resistance on the wood panel surface and in the glue line. The average values of casein-bonded samples compression strengths ranged from 1.16 N/mm2 and 2.28 N/mm2, for modulus of rupture (MOR) were measured 85 N/mm2 to 101 N/mm2 and for modulus of elasticity (MOE) 12,200 N/mm2 to 14,300 N/mm2. The screw withdrawal resistance (SWR) on the surface of the wood panels ranged from 91 N/mm to 117 N/mm and in the adhesive line from 91 N/mm to 118 N/mm. Control samples bonded with PVAc adhesive did not perform better for compression shear strength, MOR and MOE, but for SWR in the adhesive line with 114 N/mm. Casein-bonded spruce timber pressed with HF equipment represents a sustainable new product with reduced press times, hazardous emissions and improved workability.

5.
Am J Infect Control ; 47(4): 439-447, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30527285

RESUMO

BACKGROUND: Hand hygiene is crucial for preventing nosocomial infections; however, adherence rates need further attention. Prevention of nosocomial infections through regular hand hygiene monitoring and feedback is recommended by the World Health Organization. Technology holds the potential for achieving this goal. The aim of this study was to assess the influence of technological behavior monitoring innovations on hand hygiene adherence and their acceptance by healthcare professionals. METHODS: A rapid review of the literature was conducted. A literature search was performed in electronic databases (Cochrane Library, Scopus, PubMed, CINAHL, PsycINFO, PsycARTICLES, PSYNDEX) and via citation tracking in November 2017. Records were screened for eligibility. Included studies were analyzed and synthesized in a narrative, tabular way. RESULTS: Overall, 2,426 studies were identified, and 12 were included. Findings indicated that behavior monitoring technology improves hand hygiene adherence, resulting in adherence increases between 6.40%-54.97%. The majority of systems provided real-time feedback. Factors influencing acceptance of technology by healthcare professionals include transparency and confidentiality, user attitude and environment, device function, and device usability. CONCLUSIONS: Recognizing the importance of hand hygiene adherence, active communication between behavior monitoring technology and healthcare workers seems to mediate improvement in sustainable hand hygiene adherence behavior.


Assuntos
Técnicas de Observação do Comportamento/métodos , Terapia Comportamental/métodos , Higiene das Mãos/estatística & dados numéricos , Controle de Infecções/métodos , Invenções/tendências , Atitude do Pessoal de Saúde , Técnicas de Observação do Comportamento/instrumentação , Terapia Comportamental/instrumentação , Infecção Hospitalar/prevenção & controle , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Controle de Infecções/instrumentação , Aceitação pelo Paciente de Cuidados de Saúde
6.
Orphanet J Rare Dis ; 7: 35, 2012 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-22676651

RESUMO

BACKGROUND: Pompe disease (Glycogen storage disease type II, GSD II, acid alpha-glucosidase deficiency, acid maltase deficiency, OMIM # 232300) is an autosomal-recessive lysosomal storage disorder due to a deficiency of acid alpha-glucosidase (GAA, acid maltase, EC 3.2.1.20, Swiss-Prot P10253). Clinical manifestations are dominated by progressive weakness of skeletal muscle throughout the clinical spectrum. In addition, the classic infantile form is characterised by hypertrophic cardiomyopathy. METHODS: In a cross-sectional single-centre study we clinically assessed 3 patients with classic infantile Pompe disease and 39 patients with non-classic presentations, measured their acid alpha-glucosidase activities and analysed their GAA genes. RESULTS: Classic infantile patients had nearly absent residual enzyme activities and a typical clinical course with hypertrophic cardiomyopathy until the beginning of therapy. The disease manifestations in non-classic patients were heterogeneous. There was a broad variability in the decline of locomotive and respiratory function. The age of onset ranged from birth to late adulthood and correlated with enzyme activities. Molecular analysis revealed as many as 33 different mutations, 14 of which are novel. All classic infantile patients had two severe mutations. The most common mutation in the non-classic group was c.-32-13T>G. It was associated with a milder course in this subgroup. CONCLUSIONS: Disease manifestation strongly correlates with the nature of the GAA mutations, while the variable progression in non-classic Pompe disease is likely to be explained by yet unknown modifying factors. This study provides the first comprehensive dataset on the clinical course and the mutational spectrum of Pompe disease in Germany.


Assuntos
Predisposição Genética para Doença , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/fisiopatologia , Mutação , alfa-Glucosidases/genética , Adolescente , Adulto , Cardiomiopatia Hipertrófica/enzimologia , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/fisiopatologia , Cardiomiopatia Hipertrófica/terapia , Estudos Transversais , Terapia de Reposição de Enzimas , Feminino , Estudos de Associação Genética , Alemanha , Doença de Depósito de Glicogênio Tipo II/enzimologia , Doença de Depósito de Glicogênio Tipo II/terapia , Humanos , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Adulto Jovem
7.
Dev Neurobiol ; 68(7): 870-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18327766

RESUMO

Dendritic spines are assumed to constitute the locus of neuronal plasticity, and considerable effort has been focused on attempts to demonstrate that new memories are associated with the formation of new spines. However, few studies that have documented the appearance of spines after exposure to plasticity-producing paradigms could demonstrate that a new spine is touched by a bona fida presynaptic terminal. Thus, the functional significance of plastic dendritic spine changes is not clearly understood. We have used quantitative time lapse confocal imaging of cultured hippocampal neurons before and after their exposure to a conditioning medium which activates synaptic NMDA receptors. Following the experiment the cultures were prepared for 3D electron microscopic reconstruction of visually identified dendritic spines. We found that a majority of new, 1- to 2-h-old spines was touched by presynaptic terminals. Furthermore, when spines disappeared, the parent dendrites were sometime touched by a presynaptic bouton at the site where the previously identified spine had been located. We conclude that new spines are most likely to be functional and that pruned spines can be transformed into shaft synapses and thus maintain their functionality within the neuronal network.


Assuntos
Espinhas Dendríticas/ultraestrutura , Hipocampo/citologia , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Plasticidade Neuronal/fisiologia , Neurônios/citologia , Animais , Animais Recém-Nascidos , Células Cultivadas , Neurônios/fisiologia , Ratos , Fatores de Tempo
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