Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
Proc Biol Sci ; 285(1885)2018 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30135151

RESUMO

The marine mollusc, Pleurobranchaea californica varies daily in whether it swims and this correlates with whether serotonin (5-HT) enhances the strength of synapses made by the swim central pattern generator neuron, A1/C2. Another species, Tritonia diomedea, reliably swims and does not vary in serotonergic neuromodulation. A third species, Hermissenda crassicornis, never produces this behaviour and lacks the neuromodulation. We found that expression of particular 5-HT receptor subtype (5-HTR) genes in single neurons correlates with swimming. Orthologues to seven 5-HTR genes were identified from whole-brain transcriptomes. We isolated individual A1/C2 neurons and sequenced their RNA or measured 5-HTR gene expression using absolute quantitative PCR. A1/C2 neurons isolated from Pleurobranchaea that produced a swim motor pattern just prior to isolation expressed 5-HT2a and 5-HT7 receptor genes, as did all Tritonia samples. These subtypes were absent from A1/C2 isolated from Pleurobranchaea that did not swim on that day and from Hermissenda A1/C2 neurons. Expression of other receptors was not correlated with swimming. This suggests that these 5-HTRs may mediate the modulation of A1/C2 synaptic strength and play an important role in swimming. Furthermore, it suggests that regulation of receptor expression could underlie daily changes in behaviour as well as evolution of behaviour.


Assuntos
Gastrópodes/fisiologia , Regulação da Expressão Gênica , Receptores de Serotonina/genética , Animais , Encéfalo/fisiologia , Gastrópodes/genética , Hermissenda/genética , Hermissenda/fisiologia , Neurônios/fisiologia , Receptores de Serotonina/metabolismo , Especificidade da Espécie , Natação , Transcriptoma/fisiologia , Lesma Marinha/genética , Lesma Marinha/fisiologia
3.
Sci Total Environ ; 541: 1410-1419, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26479914

RESUMO

Inventory of emission sources and biomonitoring with moss transplants are two different methods to evaluate air pollution. In this study, for the first time, both these approaches were simultaneously applied in five municipalities in Campania (southern Italy), deserving attention for health-oriented interventions as part of a National Interest Priority Site. The pollutants covered by the inventory were CO, NOx, particulate matter (PM10), volatile organic compounds (VOCs), and some heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn). The biomonitoring survey was based on the use of the devitalized moss Hypnum cupressiforme transplanted into bags, following a harmonized protocol. The exposure covered 40 agricultural and urban/residential sites, with half of them located in proximity to roads. The pollutants monitored were Al, As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Se, and Zn, as well as total polycyclic aromatic hydrocarbons (PAHs) only in five sites. Using the emission inventory approach, high emission loads were detected for all the major air pollutants and the following heavy metals: Cr, Cu, Ni, Pb and Zn, over the entire study area. Arsenic, Pb, and Zn were the elements most accumulated by moss. Total PAH postexposure contents were higher than the preexposure values (~20-50% of initial value). Moss uptakes did not differ substantially among municipalities or within exposure sites. In the five municipalities, a similar spatial pattern was evidenced for Pb by emission inventory and moss accumulation. Both approaches indicated the same most polluted municipality, suggesting their combined use as a valuable resource to reveal contaminants that are not routinely monitored.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poluição do Ar/estatística & dados numéricos , Briófitas/química , Bryopsida/química , Cidades , Substâncias Perigosas , Itália , Metais Pesados/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
4.
Pflugers Arch ; 466(4): 645-60, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24515291

RESUMO

Cav3 T-type channels are low-voltage-gated channels with rapid kinetics that are classified among the calcium-selective Cav1 and Cav2 type channels. Here, we outline the fundamental and unique regulators of T-type channels. An ubiquitous and proximally located "gating brake" works in concert with the voltage-sensor domain and S6 alpha-helical segment from domain II to set the canonical low-threshold and transient gating features of T-type channels. Gene splicing of optional exon 25c (and/or exon 26) in the short III-IV linker provides a developmental switch between modes of activity, such as activating in response to membrane depolarization, to channels requiring hyperpolarization input before being available to activate. Downstream of the gating brake in the I-II linker is a key region for regulating channel expression where alternative splicing patterns correlate with functional diversity of spike patterns, pacemaking rate (especially in the heart), stage of development, and animal size. A small but persistent window conductance depolarizes cells and boosts excitability at rest. T-type channels possess an ion selectivity that can resemble not only the calcium ion exclusive Cav1 and Cav2 channels but also the sodium ion selectivity of Nav1 sodium channels too. Alternative splicing in the extracellular turret of domain II generates highly sodium-permeable channels, which contribute to low-threshold sodium spikes. Cav3 channels are more ubiquitous among multicellular animals and more widespread in tissues than the more brain centric Nav1 sodium channels in invertebrates. Highly sodium-permeant Cav3 channels can functionally replace Nav1 channels in species where they are lacking, such as in Caenorhabditis elegans.


Assuntos
Caveolina 3/fisiologia , Regulação da Expressão Gênica , Ativação do Canal Iônico/fisiologia , Potenciais da Membrana/fisiologia , Sequência de Aminoácidos , Animais , Cátions , Humanos , Dados de Sequência Molecular
5.
Ann Hum Genet ; 72(Pt 2): 253-60, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18093283

RESUMO

Starting from the observation that human longevity patterns show regional variations, we applied Spatial Analysis (using the Geographic Information System) and Surname Analysis to highlight the effect of the population genetic structure on such patterns. The study was carried out in Calabria, a southern Italian region which is characterized by a wide variability of geographic features (high mountains and deep valleys which created geographic isolates in the past). We identified three zones of high longevity: a male and a female longevity zone were located near the town of Cosenza (northern Calabria), while a male longevity zone was located in a mountainous and quite isolated part of the province of Reggio Calabria (southern Calabria). The latter zone was characterized by the lowest Female/Male ratio in nonagenarians observed to date. By applying surname analysis (Fisher's alpha) we found a significant negative correlation between surname abundance and index of longevity, showing that this isolated zone of male longevity presents a high level of inbreeding. On the whole, the results showed the effectiveness of spatial analysis in revealing geographical longevity patterns, and highlighted the importance of the population genetic structure in shaping such patterns.


Assuntos
Demografia , Genética Populacional , Endogamia , Longevidade/genética , Nomes , Idoso de 80 Anos ou mais , Feminino , Sistemas de Informação Geográfica , Geografia , Humanos , Itália , Masculino
6.
Farmaco ; 56(5-7): 397-401, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11482766

RESUMO

Camellia sinensis is a plant growing in India, Sri Lanka, Java, Japan and its properties were known 4000 years ago. Since then, traditional Chinese medicine has recommended this plant for headaches, body aches and pains, digestion, depression, detoxification, as an energiser and, in general, to prolong life. Tea contains volatile oils, vitamins, minerals, purines, polyphenols, particularly carechins. We have analysed ten commercial teas from various countries to determine their mineral composition and we have analysed a green tea, an Oolong tea and a White tea to determine their polyphenols and flavonoids content. Our study shows that the variation of mineral composition, polyphenols and flavonoids are linked to different origins of the plant. For the determination of phenols compounds and flavonoids we used an HPLC apparatus and for mineral analysis an atomic absorption apparatus.


Assuntos
Camellia sinensis/química , Flavonoides/química , Minerais/química , Chá/química , Anticolesterolemiantes/farmacologia , China , Cromatografia Líquida de Alta Pressão , Fenóis/análise , Federação Russa , Espectrofotometria Atômica , Síria
7.
Horm Behav ; 23(2): 173-84, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2744736

RESUMO

This series of experiments investigated the relationship between various treatments consisting of estradiol benzoate (EB) and progesterone (P) on sexual receptivity and on concentrations of nuclear estrogen receptors (NER) and cytosolic progestin receptors (CPR) in the hypothalamus-preoptic area in female hamsters. The injection of 1 microgram EB at 0 and 24 hr resulted in higher levels of receptivity (after 0.25 or 0.5 mg P), NER and CPR compared to those obtained after a single injection of 2 micrograms EB. Animals treated with 5 micrograms EB at 0 and 24 hr displayed greater levels of receptivity (after 0.5 mg P) and had higher NER concentrations than animals given a single injection of 10 micrograms EB. Groups treated with either 1 microgram EB at 0 hr or 0.5 microgram EB at 0 and 24 hr did not differ and showed low levels of receptivity, NER and CPR, NER and CPR were also measured on each day of the estrous cycle. NER levels rose between Days 1 and 2, again between Days 2 and 3, and remained elevated on Day 4. CPR levels increased between Days 2 and 3, and there was no difference between Days 3 and 4. Taken together, these data suggest that receptivity in hamsters after estrogen exposure is correlated with the accumulation and maintenance of relatively high NER levels and on the induction of CPR. This can be accomplished by a single large injection of EB or by smaller split doses.


Assuntos
Núcleo Celular/efeitos dos fármacos , Citosol/efeitos dos fármacos , Estradiol/farmacologia , Estro/efeitos dos fármacos , Área Pré-Óptica/efeitos dos fármacos , Progesterona/farmacologia , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Progesterona/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Cricetinae , Relação Dose-Resposta a Droga , Feminino , Ovariectomia , Projetos Piloto
8.
Boll Soc Ital Biol Sper ; 65(6): 517-20, 1989 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-2611012

RESUMO

The investigation on steroidic fraction of Uncaria tomentosa, commonly called Una de gato, showed the presence of beta-sitosterol (60%), stigmasterol, and campesterol. The percentage of sterols have been carried out by GLC. The spectroscopic data 1H-NMR and MS of the three compounds are also reported, with the beta-sitosterol as the main sterol. Preliminary pharmacological investigations prove a moderate antiinflammatory activity.


Assuntos
Anti-Inflamatórios/análise , Plantas Medicinais/análise , Esteróis/análise , Peru
10.
Boll Soc Ital Biol Sper ; 61(2): 171-4, 1985 Feb 28.
Artigo em Italiano | MEDLINE | ID: mdl-3994837

RESUMO

Sterols of three Basidiomycetes were determined. The main sterol was ergosta-5,7,22-trien-3 beta-ol, accompanied by other closely related sterols. Cholesterol was found only in trace amounts.


Assuntos
Basidiomycota/análise , Esteróis/análise , Amanita/análise , Fenômenos Químicos , Química , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...