First report of Desmiphora hirticollis (Olivier) (Coleoptera: Cerambycidae) on Wigandia urens (Ruiz and Pavón) H.B.K. (Hydrophilaceae) in Mexico

Desmiphora hirticollis (Olivier) (Coleoptera: Cerambycidae) was found in Oaxaca, Mexico, feeding in the stems of Wigandia urens (Ruiz and Pavón) H.B.K. (Hydrophilaceae), a new host record. Information about damage in the plant stems and some observations of the insect’s biology are provided

OBJETOS DE APRENDIZAGEM NA CONSTRUÇÃO DO CONCEITO DE LOGARITMOS

Resumo: Com o intuito de dinamizar a aprendizagem com este projeto de pesquisa pretende-se realizar estudo a respeito construção de um Objeto de Aprendizagem (AO) na área da matemática relativo à conceituação e aplicações dos logaritmos para o Ensino Médio. Para essa construção e significação de conceitos deve-se fazer uso da tecnologia, agregando conteúdos que podem ser acessados de forma interativa. Considera-se que as novas tecnologias têm muito a oferecer visto que a escola está inserida nesta realidade, assim como os alunos que dela fazem parte e buscam a construção de saberes. O mesmo está relacionado a linha de pesquisa: Práticas educativas que envolvam as novas tecnologias. Além de construir o OA para o estudo do tema logaritmos, pretende-se desencadear uma reflexão quanto a aprendizagem matemática com novas mídias. A coleta de dados ocorrerá a partir da aplicação de instrumento no decorrer do desenvolvimento das atividades considerando o problema de pesquisa e as aprendizagens construídas. A organização e análise de dados será na forma de categorias e considerará o referencial teórico. Neste momento estamos em fase de construção dos instrumentos de coleta de dados e revisão teórica, motivo que ainda não temos resultados a apresentar. Palavras-chaves: objetos de aprendizagem; logaritmos; ensino médio

The Anemonia sulcata Toxin BDS-I Protects Astrocytes Exposed to Aβ1–42 Oligomers by Restoring [Ca2+]i Transients and ER Ca2+ Signaling

Intracellular calcium concentration ([Ca2+]i) transients in astrocytes represent a highly plastic signaling pathway underlying the communication between neurons and glial cells. However, how this important phenomenon may be compromised in Alzheimer’s disease (AD) remains unexplored. Moreover, the involvement of several K+ channels, including KV3.4 underlying the fast-inactivating currents, has been demonstrated in several AD models. Here, the effect of KV3.4 modulation by the marine toxin blood depressing substance-I (BDS-I) extracted from Anemonia sulcata has been studied on [Ca2+]i transients in rat primary cortical astrocytes exposed to Aβ1–42 oligomers. We showed that: (1) primary cortical astrocytes expressing KV3.4 channels displayed [Ca2+]i transients depending on the occurrence of membrane potential spikes, (2) BDS-I restored, in a dose-dependent way, [Ca2+]i transients in astrocytes exposed to Aβ1–42 oligomers (5 µM/48 h) by inhibiting hyperfunctional KV3.4 channels, (3) BDS-I counteracted Ca2+ overload into the endoplasmic reticulum (ER) induced by Aβ1–42 oligomers, (4) BDS-I prevented the expression of the ER stress markers including active caspase 12 and GRP78/BiP in astrocytes treated with Aβ1–42 oligomers, and (5) BDS-I prevented Aβ1–42-induced reactive oxygen species (ROS) production and cell suffering measured as mitochondrial activity and lactate dehydrogenase (LDH) release. Collectively, we proposed that the marine toxin BDS-I, by inhibiting the hyperfunctional KV3.4 channels and restoring [Ca2+]i oscillation frequency, prevented Aβ1–42-induced ER stress and cell suffering in astrocytes

Amyloid β-Induced Upregulation of Nav1.6 Underlies Neuronal Hyperactivity in Tg2576 Alzheimer's Disease Mouse Model

Hyperexcitability and alterations in neuronal networks contribute to cognitive impairment in Alzheimer's Disease (AD). Voltage-gated sodium channels (NaV), which are crucial for regulating neuronal excitability, have been implicated in AD-related hippocampal hyperactivity and higher incidence of spontaneous non-convulsive seizures. Here, we show by using primary hippocampal neurons exposed to amyloid-β1-42 (Aβ1-42) oligomers and from Tg2576 mouse embryos, that the selective upregulation of NaV1.6 subtype contributes to membrane depolarization and to the increase of spike frequency, thereby resulting in neuronal hyperexcitability. Interestingly, we also found that NaV1.6 overexpression is responsible for the aberrant neuronal activity observed in hippocampal slices from 3-month-old Tg2576 mice. These findings identify the NaV1.6 channels as a determinant of the hippocampal neuronal hyperexcitability induced by Aβ1-42 oligomers. The selective blockade of NaV1.6 overexpression and/or hyperactivity might therefore offer a new potential therapeutic approach to counteract early hippocampal hyperexcitability and subsequent cognitive deficits in the early stages of AD

Coffee, caffeine, chlorogenic acid, and the purinergic system

Coffee is a drink prepared from roasted coffee beans and is lauded for its aroma and flavour. It is the third most popular beverage in the world. This beverage is known by its stimulant effect associated with the presence of methylxanthines. Caffeine, a purine-like molecule (1,3,7 trymetylxantine), is the most important bioactive compound in coffee, among others such as chlorogenic acid (CGA), diterpenes, and trigonelline. CGA is a phenolic acid with biological properties as antioxidant, anti-inflammatory, neuroprotector, hypolipidemic, and hypoglicemic. Purinergic system plays a key role inneuromodulation and homeostasis. Extracellular ATP, other nucleotides and adenosine are signalling molecules that act through their specific receptors, namely purinoceptors, P1 for nucleosides and P2 for nucleotides. They regulate many pathological processes, since adenosine, for instance, can limit the damage caused by ATP in the excitotoxicity from the neuronal cells. The primary purpose of this review is to discuss the effects of coffee, caffeine, and CGA on the purinergic system. This review focuses on the relationship/interplay between coffee, caffeine, CGA, and adenosine, and their effects on ectonucleotidases activities as well as on the modulation of P1 and P2 receptors from central nervous system and also in peripheral tissue

Anthocyanins restore behavioral and biochemical changes caused by streptozotocin-induced sporadic dementia of Alzheimer's type

Aims The aim of this study was to analyze if the pre-administration of anthocyanin on memory and anxiety prevented the effects caused by intracerebroventricular streptozotocin (icv-STZ) administration-induced sporadic dementia of Alzheimer's type (SDAT) in rats. Moreover, we evaluated whether the levels of nitrite/nitrate (NOx), Na+,K+-ATPase, Ca2 +-ATPase and acethylcholinesterase (AChE) activities in the cerebral cortex (CC) and hippocampus (HC) are altered in this experimental SDAT. Main methods Male Wistar rats were divided in 4 different groups: control (CTRL), anthocyanin (ANT), streptozotocin (STZ) and streptozotocin + anthocyanin (STZ + ANT). After seven days of treatment with ANT (200 mg/kg; oral), the rats were icv-STZ injected (3 mg/kg), and four days later the behavior parameters were performed and the animals submitted to euthanasia. Key findings A memory deficit was found in the STZ group, but ANT treatment showed that it prevents this impairment of memory (P < 0.05). Our results showed a higher anxiety in the icv-STZ group, but treatment with ANT showed a per se effect and prevented the anxiogenic behavior induced by STZ. Our results reveal that the ANT treatment (100 μM) tested displaces the specific binding of [3H] flunitrazepam to the benzodiazepinic site of GABAA receptors. AChE, Ca+-ATPase activities and NOx levels were found to be increased in HC and CC in the STZ group, which was attenuated by ANT (P < 0.05). STZ decreased Na+,K+-ATPase activity and ANT was able to prevent these effects (P < 0.05). Significance In conclusion, these findings demonstrated that ANT is able to regulate ion pump activity and cholinergic neurotransmission, as well as being able to enhance memory and act as an anxiolytic compound in animals with SDAT

OBJETOS DE APRENDIZAGEM NA CONSTRUÇÃO DO CONCEITO DE LOGARITMOS

Normal 0 21 false false false PT-BR X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Resumo: Com o intuito de dinamizar a aprendizagem com este projeto de pesquisa pretende-se realizar estudo a respeito construção de um Objeto de Aprendizagem (AO) na área da matemática relativo à conceituação e aplicações dos logaritmos para o Ensino Médio. Para essa construção e significação de conceitos deve-se fazer uso da tecnologia, agregando conteúdos que podem ser acessados de forma interativa. Considera-se que as novas tecnologias têm muito a oferecer visto que a escola está inserida nesta realidade, assim como os alunos que dela fazem parte e buscam a construção de saberes. O mesmo está relacionado a linha de pesquisa: Práticas educativas que envolvam as novas tecnologias. Além de construir o OA para o estudo do tema logaritmos, pretende-se desencadear uma reflexão quanto a aprendizagem matemática com novas mídias. A coleta de dados ocorrerá a partir da aplicação de instrumento no decorrer do desenvolvimento das atividades considerando o problema de pesquisa e as aprendizagens construídas. A organização e análise de dados será na forma de categorias e considerará o referencial teórico. Neste momento estamos em fase de construção dos instrumentos de coleta de dados e revisão teórica, motivo que ainda não temos resultados a apresentar. Palavras-chaves: objetos de aprendizagem; logaritmos; ensino médio.</p

OBJETOS DE APRENDIZAGEM UMA PROPOSTA PRÁTICA PARA O ENSINO DE LOGARITMO

Resumo: Este trabalho tem por objetivo apresentar um estudo a respeito de um Objeto de Aprendizagem-OA na exploração do tema logaritmo. Considera um referencial relacionado a práticas educativas que envolvem tecnologias e a discussão a respeito da aprendizagem matemática com a utilização de OA no ensino. Considerando que as Tecnologias da Informação e Comunicação (TIC’s)  têm muito a oferecer, visto que a escola encontra-se inserida nesta realidade, pretende-se com este estudo desencadear uma reflexão quanto à aprendizagem matemática com mídias. Os dados e resultados do estudo apontam a relevância do material estabelecido e utilizado bem como a e sua importância à aprendizagem do conceito de logaritmo. Sendo assim, neste artigo apresenta-se uma contribuição à prática docente a partir de um OA.Palavras-chaves: Objeto de aprendizagem; Logaritmos; Ensino Médio; Tecnologia.</p

First report of \u3ci\u3eDesmiphora hirticollis\u3c/i\u3e (Olivier) (Coleoptera: Cerambycidae) on \u3ci\u3eWigandia urens\u3c/i\u3e (Ruiz and Pavón) H.B.K. (Hydrophilaceae) in Mexico

ABSTRACT. Desmiphora hirticollis (Olivier) (Coleoptera: Cerambycidae) was found in Oaxaca, Mexico, feeding in the stems of Wigandia urens (Ruiz and Pavón) H.B.K. (Hydrophilaceae), a new host record. Information about damage in the plant stems and some observations of the insect’s biology are provided. RESUMEN. Se reporta por primera vez en México la presencia del cerambícido Desmiphora hirticollis (Olivier) (Coleoptera: Cerambycidae) alimentándose de los tallos de Wigandia urens (Ruiz and Pavón) H.B.K. (Hydrophilaceae). Se proporciona información sobre los daños que provoca este insecto a los tallos de la planta, así como algunas observaciones biológicas del insecto

Reticular synthesis, topological studies and physicochemical properties of a 3D manganese(II) coordination network [Mn3(BTC)2(DMSO)4]n

In order to build a metal-organic framework with mixed ligands (acid-acid), a 3D coordination network based on manganese metal center was obtained [Mn3(BTC)2(DMSO)4]n; where BTC = Benzene-1,3,5-tricarboxylic acid and DMSO = Dimethylsulfoxide. The crystal structure was determined by single crystal X-ray diffraction, showing the assembly of a tridimensional 3,6-connected non-entangled polymeric network, with RTL topology. The secondary building unit (SBU) acts as a node of the 3-periodic expansion and involves carboxylate- and oxo-bridged metals. The DMSO employed in the synthesis is chemically involved in the coordination as a µ2-O bridge between distinct manganese metal centers. The structural characterization of the material was supported by spectroscopic (infrared absorption and Raman scattering), thermal (TG, DTG, and DTA) and elemental analysis