Saturday, 29 December 2018

World’s first true blue roses could be coming soon!




By expressing bacterial genes, white rose petals can take on a blue hue (Image: American Chemical Society)



For centuries, gardeners have attempted to breed blue roses with no success. But now, thanks to modern biotechnology, the elusive blue rose may finally be attainable. Researchers have found a way to express pigment-producing enzymes from bacteria in the petals of a white rose, tinting the flowers blue.

Although blue roses do not exist in nature, florists can produce blue-hued flowers by placing cut roses in dye. Also, in a painstaking 20-year effort, biotechnologists made a "blue rose" through a combination of genetic engineering and selective breeding. However, the rose is more mauve-colored than blue. 

A completely different strategy presented in this study employs a dual expression plasmid containing bacterial idgS and sfp genes. The holo-IdgS, activated by Sfp from its apo-form, is a functional nonribosomal peptide synthetase that converts l-glutamine into the blue pigment indigoidine. Expression of these genes upon petal injection with agro-infiltration solution generates blue-hued rose flowers. We envision that implementing this proof-of-concept with obligatory modifications may have tremendous impact in floriculture to achieve a historic milestone in rose breeding.

Ref: Ankanahalli N. Nanjaraj Urs, Yiling Hu, Pengwei Li, Zhiguang Yuchi, Yihua Chen, Yan Zhang. Cloning and Expression of a Nonribosomal Peptide Synthetase to Generate Blue Rose. ACS Synthetic Biology, 2018; DOI: 10.1021/acssynbio.8b00187

Thursday, 19 April 2018

More than five glasses of alcoholic drink could shorten your life


According to new research from the University of Cambridge, regularly drinking more than the recommended UK guidelines for alcohol could take years off your life. The study compared the health and drinking habits of over 600,000 people in 19 countries worldwide and controlled for age, smoking, history of diabetes, level of education and occupation.
The upper safe limit of drinking was about five drinks per week (100g of pure alcohol, 12.5 units or just over five pints of 4% ABV beer or five 175ml glasses of 13% ABV wine). However, drinking above this limit was linked with lower life expectancy.
Alcohol consumption was associated with a higher risk of stroke, heart failure, fatal aortic aneurysms, fatal hypertensive disease and heart failure and there were no clear thresholds where drinking less did not have a benefit.

Cardiovascular disease may relate to alcohol's elevating effects on blood pressure and on factors related to elevated high-density lipoprotein cholesterol (HDL-C) (also known as 'good' cholesterol).  Alcohol consumption is associated with a slightly lower risk of non-fatal heart attacks but this must be balanced against the higher risk associated with other serious and potentially fatal cardiovascular diseases.

If you already drink alcohol, drinking less may help you live longer and lower your risk of several cardiovascular conditions.
1.      

   Ref. Angela M Wood et al. Risk thresholds for alcohol consumption: combined analysis of individual-participant data for 599 912 current drinkers in 83 prospective studiesThe Lancet, 2018; 391 (10129): 1513 DOI: 10.1016/S0140-6736(18)30134-X
     

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Thursday, 12 April 2018

Are babies capable of identifying the emotions expressed by adults?

The ability of babies to differentiate emotional expressions appears to develop during their first six months. But do they really recognize emotion or do they only distinguish the physical characteristics of faces and voices? Researchers have just provided an initial answer to this question, measuring the ability of six-month-old babies to make a connection between a voice expressing happiness or anger and the emotional expression on a face.
6-month-old infants could transfer amodal information from emotional voices to emotional faces. Thus, sequences of successive emotional stimuli (voice or face from one sensory modality -auditory- to another sensory modality -visual-), corresponding to a cross-modal transfer, were displayed to 24 infants. Each sequence presented an emotional (angry or happy) or neutral voice, uniquely, followed by the simultaneous presentation of two static emotional faces (angry or happy, congruous or incongruous with the emotional voice). Eye movements in response to the visual stimuli were recorded with an eye-tracker. First, results suggested no difference in infants’ looking time to happy or angry face after listening to the neutral voice or the angry voice. Nevertheless, after listening to the happy voice, infants looked longer at the incongruent angry face (the mouth area in particular) than the congruent happy face. These results revealed that a cross-modal transfer (from auditory to visual modalities) is possible for 6-month-old infants only after the presentation of a happy voice, suggesting that they recognize this emotion amodally.
The results of the study revealed that six-month-olds did not have a preference for either of the emotional faces if they had already heard a neutral voice or a voice expressing anger. On the other hand, they spent longer looking at the face expressing anger - especially its mouth - after hearing a voice expressing happiness. This visual preference for novelty on the part of six-month-olds testifies of their early ability to transfer emotional information about happiness from the auditory to the visual mode.

Ref: Amaya Palama, Jennifer Malsert, Edouard Gentaz. Are 6-month-old human infants able to transfer emotional information (happy or angry) from voices to faces? An eye-tracking study. PLOS ONE, 2018; 13 (4): e0194579 DOI: 10.1371/journal.pone.0194579

Monday, 12 February 2018

Dim light may make us dumber

BLD- Bright light
DLD- Dim light
Credit: Michigan State University

The researchers studied the brains of Nile grass rats (which, like humans, are diurnal and sleep at night) after exposing them to dim and bright light for four weeks. The rodents exposed to dim light lost about 30 percent of capacity in the hippocampus, a critical brain region for learning and memory, and performed poorly on a spatial task they had trained on previously.

The rats exposed to bright light, on the other hand, showed significant improvement on the spatial task. Further, when the rodents that had been exposed to dim light were then exposed to bright light for four weeks (after a month-long break), their brain capacity and performance on the task recovered fully.
Sustained exposure to dim light led to significant reductions in a substance called brain derived neurotrophic factor - a peptide that helps maintain healthy connections and neurons in the hippocampus and in dendritic spines, or the connections that allow neurons to "talk" to one another.
This results in diminished learning and memory performance that is dependent upon the hippocampus, dim lights are producing dimwits.

Ref: Joel et al., Light modulates hippocampal function and spatial learning in a diurnal rodent species: A study using male nile grass rat (Arvicanthis niloticus). Hippocampus, 2017.
1.    DOI: 10.1002/hipo.22822