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Thursday, March 2, 2017

Study: Brain Produces Fructose from Glucose

Study: Brain Produces Fructose from Glucose

Feb 24, 2017 by News Staff / Source
According to a new study by Yale School of Medicine researchers, fructose is converted in the human brain from glucose. The finding, published in thejournal JCI Insight, raises questions about fructose’s effects on the brain and eating behavior.
Fructose, a simple sugar, is generated in the human brain, according to Hwang et al. Image credit: Pete Linforth /
Fructose, a simple sugar, is generated in the human brain, according to Hwang et al. Image credit: Pete Linforth /
Fructose, or fruit sugar, is a natural simple sugar found in fruits, honey, vegetables, and many processed foods.
Excess consumption of fructose contributes to high blood sugar and chronic diseases like obesity.
Dr. Janice Hwang, an endocrinologist and an assistant professor in the Division of Endocrinology at the Yale School of Medicine, and co-authors had demonstrated in a prior study that fructose and another simple sugar, glucose, had different effects on brain activity.
But it was not known whether fructose was produced in the brain or crossed over from the bloodstream.

To investigate, the team gave eight healthy, lean individuals infusions of glucose over a four-hour period.
They measured sugar concentrations in the brains of the study participants using magnetic resonance spectroscopy (MRS). Sugar concentrations in the blood were also assessed.
“In this study, we use MRS scanning, which allows for noninvasive direct measurements of metabolite concentrations to test an alternate mechanism, namely that fructose is produced endogenously within the human brain from glucose via a metabolic pathway called the polyol pathway (glucose > sorbitol > fructose),” Dr. Hwang and her colleagues explained.
“The polyol pathway is an accessory glucose pathway that bypasses glycolysis, and in the setting of hyperglycemia, up to 30% of glucose can be metabolized via this alternate pathway.”
“Eight healthy subjects (4 women/4 men; age – 28.8 years) underwent MRS scanning to measure intracerebral glucose and fructose levels during a 4-hour hyperglycemic clamp.”
The researchers found cerebral fructose levels rose significantly in response to a glucose infusion, with minimal changes in fructose levels in the blood.
They surmised that the high concentration of fructose in the brain was due to the polyol pathway.
“In this study, we show for the first time that fructose can be produced in the human brain,” Dr. Hwang said.
“While the production of fructose in the brain had been seen in animals, it had not been demonstrated in humans.”
The finding raises several key research questions, which the authors plan to pursue.
“By showing that fructose in the brain is not simply due to dietary consumption of fructose, we’ve shown fructose can be generated from any sugar you eat. It adds another dimension into understanding fructose’s effects on the brain,” Dr. Hwang said.
Glucose in the brain sends signals of fullness, but that is not the case with fructose.”
According to the researchers, the conversion of glucose to fructose in the brain also occurs in other parts of the body.
“This pathway may be one other mechanism by which high blood sugar can exert its adverse effects,” Dr. Hwang said.
Janice J. Hwang et al. 2017. The human brain produces fructose from glucose. JCI Insight 2 (4): e90508; doi: 10.1172/jci.insight.90508

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How to Digitally Record/Video a UFO sighting:

Como registar digitalmente ou gravar um vídeo de um avistamento de um UFO:

Stabilize the camera on a tripod. If there is no tripod, then set it on top of a stable, flat surface. If that is not possible lean against a wall to stabilize your body and prevent the camera from filming in a shaky, unsteady manner.

Estabilize a camera com um tripé. Se não tiver um tripé, então coloque-a em cima de uma superfície estável. Se não for possível, então encoste-se a uma parede para estabilizar o corpo e evitar que a camera registe de maneira tremida e instável.

Provide visual reference points for comparison. This includes the horizon, treetops, lampposts, houses, and geographical landmarks (i.e., Horsetooth Reservoir, Mt. Adams, etc.) Provide this in the video whenever is appropriate and doesn’t detract from what your focus is, the UFO.

Forneça pontos visuais de referência para comparação. Isso inclui o horizonte, cimo das árvores, postes de iluminação, pontos de referência geográficos (como o Reservatório de Horsetooth, Mone Adams, etc) Forneça esses pontos no vídeo sempre que for apropriado e não se distraia do que é o seu foco, o UFO/a Nave.

Narrate your videotape. Provide details of the date, time, location, and direction (N,S,E,W) you are looking in. Provide your observations on the weather, including approximate temperature, windspeed, any visible cloud cover or noticeable weather anomalies or events. Narrate on the shape, size, color, movements, approximate altitude of the UFO, etc and what it appears to be doing. Also include any unusual physical, psychological or emotional sensations you might have. Narrate any visual reference points on camera so they correlate with what the viewer will see, and thereby will be better able to understand.

Faça a narração do vídeo. Forneça pormenores sobre a data, hora, local e direcção (Norte, Sul, Este, Oeste) que está a observar. Faça observações sobre as condições atmosféricas, incluindo a temperatura aproximada, velocidade do vento, quantidade de nuvens, anomalias ou acontecimentos meteorológicos evidentes. Descreva a forma, o tamanho, a cor, os movimentos, a altitude aproximada onde se encontra o UFO/nave, etc e o que aparenta estar a fazer. Inclua também quaisquer aspectos pouco habituais de sensações físicas, psicológicas ou emocionais que possa ter. Faça a narração de todos os pontos de referência visual que o espectador irá ver e que, deste modo, será capaz de compreender melhor.

Be persistent and consistent. Return to the scene to videotape and record at this same location. If you have been successful once, the UFO sightings may be occurring in this region regularly, perhaps for specific reasons unknown, and you may be successful again. You may also wish to return to the same location at a different time of day (daylight hours) for better orientation and reference. Film just a minute or two under “normal” circumstances for comparison. Write down what you remember immediately after. As soon as you are done recording the experience/event, immediately write down your impressions, memories, thoughts, emotions, etc. so it is on the record in writing. If there were other witnesses, have them independently record their own impressions, thoughts, etc. Include in this exercise any drawings, sketches, or diagrams. Make sure you date and sign your documentation.

Seja persistente e não contraditório. Volte ao local da cena e registe o mesmo local. Se foi bem sucedido uma vez, pode ser que nessa região ocorram avistamentos de UFOs/naves com regularidade, talvez por razões específicas desconhecidas, e talvez possa ser novamente bem sucedido. Pode também desejar voltar ao mesmo lugar a horas diferentes do dia (durante as horas de luz)para ter uma orientação e referência melhor. Filme apenas um ,inuto ou dois em circunstâncias “normais” para ter um termo de comparação. Escreva tudo o que viu imediatamente após o acontecimento. Logo após ter feito o registo da experiência/acontecimento, escreva imediatamente as impressões, memórias, pensamentos, emoções, etc para que fiquem registadas por escrito. Se houver outras testemunhas, peça-lhes para registar independentemente as suas próprias impressões, pensamentos, etc. Inclua quaisquer desenhos, esbolos, diagramas. Certifique-se que data e assina o seu documento/testemunho.

Always be prepared. Have a digital camera or better yet a video camera with you, charged and ready to go, at all times. Make sure you know how to use your camera (and your cell phone video/photo camera) quickly and properly. These events can occur suddenly, unexpectedly, and often quite randomly, so you will need to be prepared.

Esteja sempre preparado, Tenha sempre uma camera digital, melhor ainda, uma camera vídeo consigo, carregada e pronta a usar sempre que necessário. Certifique-se que sabe como lidar com a sua camera (ou com o seu celular/camera fotográfica) rápida e adequadamente. Esses acontecimentos podem acontecer súbita e inesperadamente e, por vezes, acidentalmente, por isso, necessita estar preparado.

Look up. Be prepared. Report. Share.

Olhe para cima, Esteja preparado, Relate, Partilhe.



Pf., clique no símbolo do YouTube e depois no quadrado pequeno, em baixo, ao lado direito para obter as legendas CC, e escolha PORTUGUÊS

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What time is Around the World?


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NGC - UFO's in EUROPE (Porugal included)

FEBRUARY 7, 2013 - 7:00PM EST

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