RESUMO
Here, we report a quick and low-cost method to improve plant transformation using Agrobacterium tumefaciens. This method involves the use of physical wounding, ultrasound, and an increase in exposure time to the bacteria. We show how the transformation rate increased from 0 to 14% when an ultrasound pulse of 10 s was used in conjunction with 96 h of bacterial exposure in Eclipta alba explants.
Assuntos
Agrobacterium tumefaciens/genética , DNA Bacteriano/genética , Eclipta/genética , Caules de Planta/genética , Plantas Geneticamente Modificadas , Transformação Genética , Agrobacterium tumefaciens/metabolismo , Antibacterianos/farmacologia , DNA Bacteriano/metabolismo , Eclipta/efeitos dos fármacos , Eclipta/microbiologia , Eclipta/efeitos da radiação , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Canamicina/farmacologia , Resistência a Canamicina , Caules de Planta/efeitos dos fármacos , Caules de Planta/microbiologia , Caules de Planta/efeitos da radiação , Ondas UltrassônicasRESUMO
Alzheimer's disease (AD) is a severe neurodegenerative disorder still in search of effective methods of diagnosis. Altered levels of the NMDA receptor co-agonist, d-serine, have been associated with neurological disorders, including schizophrenia and epilepsy. However, whether d-serine levels are deregulated in AD remains elusive. Here, we first measured D-serine levels in post-mortem hippocampal and cortical samples from nondemented subjects (n=8) and AD patients (n=14). We next determined d-serine levels in experimental models of AD, including wild-type rats and mice that received intracerebroventricular injections of amyloid-ß oligomers, and APP/PS1 transgenic mice. Finally, we assessed d-serine levels in the cerebrospinal fluid (CSF) of 21 patients with a diagnosis of probable AD, as compared with patients with normal pressure hydrocephalus (n=9), major depression (n=9) and healthy controls (n=10), and results were contrasted with CSF amyloid-ß/tau AD biomarkers. d-serine levels were higher in the hippocampus and parietal cortex of AD patients than in control subjects. Levels of both d-serine and serine racemase, the enzyme responsible for d-serine production, were elevated in experimental models of AD. Significantly, d-serine levels were higher in the CSF of probable AD patients than in non-cognitively impaired subject groups. Combining d-serine levels to the amyloid/tau index remarkably increased the sensitivity and specificity of diagnosis of probable AD in our cohort. Our results show that increased brain and CSF d-serine levels are associated with AD. CSF d-serine levels discriminated between nondemented and AD patients in our cohort and might constitute a novel candidate biomarker for early AD diagnosis.
Assuntos
Doença de Alzheimer/metabolismo , Biomarcadores/metabolismo , Córtex Cerebral/metabolismo , Hipocampo/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/toxicidade , Precursor de Proteína beta-Amiloide/genética , Animais , Biomarcadores/líquido cefalorraquidiano , Estudos de Casos e Controles , Transtorno Depressivo Maior/líquido cefalorraquidiano , Modelos Animais de Doenças , Feminino , Humanos , Hidrocefalia de Pressão Normal/líquido cefalorraquidiano , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Ratos , SerinaRESUMO
Snakebites comprise a serious health problem in several countries due to their global incidence, which exceeds 2.5 million per year, and the elevated number of victim fatalities. To counteract envenomations, antivenoms have been used regularly for more than a century. Apart from side effects including anaphylactic reactions, antivenoms are not able to efficiently neutralize local tissue damage, which contributes to increasing the severity and morbidity observed in patients. This fact, in turn, may be responsible for economic hardship, particularly in rural populations of developing countries. In the present work, we evaluated the antiophidian properties of 12 Brazilian plant extracts against the hemolytic, coagulant, hemorrhagic and proteolytic effects of Lachesis muta venom. Taken together, our data revealed that most of these aqueous products were capable of inhibiting those activities at different levels, except for Sapindus saponaria extract. In contrast, Stryphnodendron barbatiman extract completely neutralized all the analyzed biological activities. Thus, we may conclude that Brazilian flora may also be useful against L. muta accidents.
