20170831

Trial raises Parkinson's therapy hope  
Scientists have restored nerve cells destroyed by a condition similar to Parkinson's disease, in monkeys.
The Japanese team hope their work could lead to stem cell trials in human patients before the end of 2018.
Parkinson's disease causes the progressive loss of nerve cells that release dopamine, a chemical that helps control body movement.
ドーパミン は、中枢神経系に存在する神経伝達物質で、アドレナリン、ノルアドレナリンの前駆体でもある。運動調節、ホルモン調節、快の感情、意欲、学習などに関わる。
The researchers triggered a similar loss of cells in macaque monkeys, then used human stem cells to replace them.
The animals showed significant improvement in their symptoms two years after having precursor dopamine neurons derived from human stem cells transplanted into their brains.
ドーパミンを産生する神経細胞（ドーパミンニューロン）
precursor化学における 前駆体（ぜんくたい）とは、ある化学物質について、その物質が生成する前の段階の物質のことを指す。
These cells - known as induced pluripotent stem (iPS) cells - are created by genetically reprogramming ordinary adult cells, so that they revert to an embryonic-like state.
人工多能性幹細胞  induced pluripotent stem cellsとは、体細胞へ数種類の遺伝子を導入することにより、ES細胞（胚性幹細胞）のように非常に多くの細胞に分化できる分化万能性 (pluripotency)と、分裂増殖を経てもそれを維持できる自己複製能を持たせた細胞のこと。
In this state, they can then be coaxed to develop into many different adult cell types - in the case of this experiment, dopamine neurons.
coax  【他動】 （人）を説得する［誘導する・まるめ込む］、（人）をおだてて［うまく説得して・口車に乗せて］～させる
Researcher Prof Jun Takahashi, from Kyoto University, said the work, published in the journal Nature, showed that the artificially created cells were as effective as those created naturally in the brain of the monkeys.
He said: "Because iPS cells are easy to obtain, we can standardise them to only use the best iPS cells for therapy."
Brain scans confirmed the cells were functioning as expected and not triggering a damaging immune response, or the growth of cancerous tumours, which can be associated with experimental stem cell therapies.
The researchers also found that the quality of the donor cells was the key factor - not how many each monkey received.
Dr Tilo Kunath, a Parkinson's UK-funded researcher at the Medical Research Council Centre for Regenerative Medicine at the University of Edinburgh, said: "This is extremely promising research demonstrating that a safe and highly effective cell therapy for Parkinson's can be produced in the lab.
"Such a therapy has the potential to reverse the symptoms of Parkinson's in patients by restoring their dopamine-producing neurons.
"The next stage will be to test these therapies in a first-in-human clinical trial."
Prof Tom Foltynie, of the National Hospital for Neurology & Neurosurgery, said there would be concerns about how stem cell transplants might pan out in human Parkinson's patients, but the latest work had addressed some of the previous uncertainty about whether it was safe to use iPS cells.
pan out 【句動】成功する、計画がうまくいく
He said "Overall, the results they report in the short term are encouraging and provide some reassurance that these cells can function as sources of dopamine to address those movement symptoms of Parkinson's disease that relate to dopamine loss.
"No-one expects that transplants will address the non-dopamine, non-movement aspects of Parkinson's disease such as dementia and falls, which ultimately emerge with very long-term follow up."

20170830

Anti-inflammatory drug 'cuts heart attack risk'
Anti-inflammatory drugs could cut the risk of heart attacks and strokes, a study of 10,000 patients suggests.
A trial of the drug canakinumab could represent the biggest breakthrough in treatment since the advent of statins to lower cholesterol, its authors say.
カナキヌマブ（Canakinumab）は、インターロイキン-1βを標的とするヒトモノクローナル抗体である。
canakinumabノバルティス社は心筋梗塞の既往症を有する患者、およびアテローム性動脈硬化症の患者に対するcanakinumabの試験において、心血管イベントリスクが減少したことを発表しました。 重大な副作用には、重篤な感染症（敗血症、日和見感染症（アスペルギルス症、非定型抗酸菌症、帯状疱疹等）等）と好中球減少が明記されている。感染症は時に致命的な転帰を辿る。
インターロイキン-1β
体内において白血球およびその他の細胞によって作られる互いに関連しあう一群の蛋白のひとつ。インターロイキン-1-βはインターロイキン-1の一種であり、主に白血球の一種であるマクロファージによって作られ、別の種類の白血球であるリンパ球が感染に対する防御を行う手助けをする。また、白血球が血管壁を通り抜けて感染部位に移動するのを助けたり、体温を制御している脳の領域に作用して発熱を引き起こしたりする作用もある。
モノクローナル抗体は、ただ1種類のB細胞が作る抗体のコピー、つまりクローンです。モノは「単一」、クローナルは「混じりっけのない集合」を意味します。 特定の抗原決定基だけと結合する抗体の集合体をモノクローナル抗体という。
statin 【名】 コレステロールの生合成に関わる酵素を阻害することによって、血清コレステロールのレベルを下げ、脂肪を減らす薬。
advent  【名】 出現、到来
The study reported a 15% reduction in the risk of a repeat heart attack among patients - but others questioned the drug's efficacy, side-effects and cost.
Recipients of the drug had an increased risk of potentially fatal infections.
However, the British Heart Foundation (BHF) said the "exciting and long-awaited trial" could still help save lives.
Arthritis drug
Heart attack patients are routinely given cholesterol-lowering statins and blood-thinning drugs to help reduce the risk of repeat attacks.
blood-thinning drug  抗凝血剤
In this study, 10,000 patients who had previously had a heart attack were treated with the anti-inflammatory drug once every three months.
The trial, held in almost 40 countries, monitored the individuals for up to four years.
It found what researchers said were reductions in risk "above and beyond" those seen in patients who only took statins.
However, it also found a "significantly higher incidence" of potentially fatal infection and sepsis among those treated with the drug, according to the study.
sepsis【名】 《病理》敗血症
敗血症とは、感染に対する制御不能な生体反応に起因する生命を脅かすような臓器障害のことで、細菌感染症の全身に波及したもので非常に重篤な状態であり、無治療ではショック、DIC、多臓器不全などから早晩死に至る。元々の体力低下を背景としていることが多く、治療成績も決して良好ではない。
The results were presented at the European Society of Cardiology meeting, held in Barcelona, Spain.
Canakinumab was initially developed by pharmaceutical firm Novartis - which paid for the trial - to treat rheumatoid arthritis.
paid-for 【形】 有料の、有償の
rheumatoid arthritis 《病理》関節リウマチ、リウマチ性関節炎
自己の免疫が主に手足の関節を侵し、これにより関節痛、関節の変形が生じる代表的な膠原病の1つで、炎症性自己免疫疾患である。
Heart attack patients are routinely treated with statins
A heart attack is a serious medical emergency in which the supply of blood to the heart is suddenly blocked.
Experts have previously spoken about its possible link with inflammation of certain blood vessels. However, authors say such a link has never been proven before in humans.
The study's lead author Dr Paul Ridker, of Brigham and Women's Hospital, part of Harvard Medical School, said the study represented "a milestone in a long journey".
"For the first time, we've been able to definitively show that lowering inflammation independent of cholesterol reduces cardiovascular risk," he said.
"This has far-reaching implications."
Dr Ridker continued: "In my lifetime, I've gotten to see three broad eras of preventative cardiology.
"In the first, we recognised the importance of diet, exercise and smoking cessation. In the second, we saw the tremendous value of lipid-lowering drugs such as statins. Now, we're cracking the door open on the third era.
crack〔強盗がドア・窓・壁を破壊して建物の中に〕押し入る
 This is very exciting."
Dr Ridker said the findings also indicated "the possibility of slowing the progression of certain cancers", but further research was required.
'Safety trade-offs'
Dr Robert Harrington, chair of the Stanford University School of Medicine, sounded a note of caution in an editorial in the New England Journal of Medicine.
He said the effects of anti-inflammatories could be "modest", and the absolute clinical benefit of canakinumab "cannot justify" its routine use "until we understand more about the efficacy and safety trade-offs, and unless a price restructuring and formal cost-effectiveness evaluation supports it."
Others, though, say the treatment could help those at risk of repeat heart attacks for whom statins are not enough.
Prof Jeremy Pearson, associate medical director at the BHF, said: "The findings suggest that existing anti-inflammatory drugs, such as canakinumab, could be given along with cholesterol-lowering drugs to treat survivors and further reduce their risk of another heart attack."
Gary Gibbons, director of the National Heart, Lung, and Blood Institute, said the findings provided "compelling evidence".
compelling evidence有力な証拠
He called for further research into the findings.

​20170829

'A pedometer saved my life': How I became fit in my 60s
Graham's doctor suggested he join a local walking group in Stockport two years ago.
Graham Ward was 60 when he was diagnosed with type 2 diabetes.
It came after decades of eating and drinking too much in a high-stress, sedentary job: "It was an explosion waiting to happen," he said.
type 2 diabetes 《病理》2型糖尿病
インスリンをつくることができるが、ブドウ糖が効率よく細胞に取り入れられないタイプの糖尿病
糖尿病の約90%が2型糖尿病であり、その他10%は1型糖尿病と妊娠糖尿病である。 1型糖尿病は膵臓にてランゲルハンス島が分解され絶対的インスリン不足になる病気である。2型糖尿病では、肥満などを原因として、膵臓のランゲルハンス島(膵島)にあるβ細胞からのインスリン分泌量が減少し、筋肉、脂肪組織へのグルコースの取り込み能が低下(インスリン抵抗性が増大)し、結果として血中のグルコースが肝臓や脂肪組織でグリコーゲンとして貯蔵されず、血中のグルコースが正常範囲を逸脱して高い血糖値となり、糖尿病となる。
sedentary【形】座って行う、デスクワークの
accident waiting to happenいつ事故が起きてもおかしくない状態、起こるべくして起こった事故
For Graham, whose wife had become increasingly disabled through multiple sclerosis, the diagnosis was a wake-up call.
multiple sclerosis 多発性硬化（症）
中枢性脱髄疾患の一つで、神経のミエリン鞘が破壊され脳、脊髄、視神経などに病変が起こり、多様な神経症状が再発と寛解を繰り返す疾患で、日本では特定疾患に認定されている指定難病である。 病名は、神経を包む組織（ミエリン鞘）が破壊されて生じる硬化が多数の領域で発生することに由来している 。
"I need to be able to help her - and I need to be around for longer," he said.
Graham is not alone in his diagnosis.
Public Health England estimates that 42% of 45- to 64-year-olds have a long-term health condition such as diabetes or heart disease.
This week, it urged middle-aged people to walk more often and more briskly.
It is encouraging those between the ages of 40 and 60 to start doing regular brisk walks of just 10 minutes a day.
One in five middle-aged people is physically inactive, engaging in less than 30 minutes of exercise a week, it says.
To help, the government agency is promoting a free app - Active 10 - which can monitor the amount of brisk walking an individual does and provide tips on how to incorporate more of it into the daily routine.
When Graham was diagnosed as a diabetic, he realised he needed to make changes: "My clothes were getting tighter, and I was hearing how being overweight could affect my life and health in other ways," he said.
Diabetes has been linked to other issues such as heart disease, stroke and kidney disease, causing a reduction in one's life expectancy.
He said beforehand he had managed to turn a blind eye to this.
beforehand【副】 あらかじめ、事前に 早計で
turn a blind eye  〔悪事や解決すべき問題などについて〕見て見ぬふりをする、気付かぬ［知らぬ］ふりをする、目をつぶる
"When someone is in front of you telling you it's you, there's nowhere to hide," he said.
"They're not talking about the other millions of people out there."
Graham's doctor suggested he should join a local walking group in Stockport.
"I started and I was a bit nervous. With a couple of hills, it was more walking than I'd been doing," he said.
He was talked into the 1.9 mile walk by the group leader.
"After the first time, I overcame all those fears."
He invested in a pair of new shoes and gradually increased his walks to reach five miles.  
Over a period of months, Graham graduated from walking three kilometres to eight kilometres
"It was a very quick improvement, once you realise after the first one or two that you don't become immediately breathless and that you can walk further from home than you thought," said Graham.
"I moved on from walking with that group, to walking by myself, walking further distances and the pounds started falling off me."
He used a pedometer to make sure he was reaching the recommended 10,000 steps a day.
Now he does about 15,000 steps and has lost 50lb.
"My trousers were falling off me. I had to throw away all the clothes I owned," he said.
Graham said the benefits were not only physical.
"I'm fitter, healthier, more confident. When you start walking you see things in your area that you haven't seen before, such as discovering canal towpaths."
His advice to others is not to be "disappointed if it doesn't happen in the first few weeks".
Now, he and his wife diet and swim together.
"When I'm playing with my grandchildren now, it's them that get tired before me," Graham said.

20170828

What's really the point of wasps?
not realize what the point is趣旨が分からない
A new citizen science survey aims to shed light on that fixture of summertime in the outdoors: the wasp. Though much maligned, these fascinating creatures perform a vital ecological role, say scientists.
fixture【名】居座る人
much-maligned【形】厳しく中傷された    中傷を受けている
The only thing more certain to spoil an August Bank Holiday weekend BBQ than a sudden cloudburst? The arrival of wasps.
August Bank Holiday 《the ～》〈英〉オーガスト・バンク・ホリデー、8月の祭日◆ウェールズとイングランドでは8月の最終月曜日、スコットランドでは8月の最初の月曜日の夏休暇（the summer bank holiday）のこと
At this time of the year, it can sometimes seem as if every outdoor activity is plagued by these yellow-and-black striped insects buzzing around your head and landing on your food and drink.
Wasps aren't just annoying - if you are unlucky, you might end up with a sharp reminder that wasps, like their close relatives the honeybee, pack a powerful sting. That combination of nuisance and pain makes wasps many people's least favourite animals.
reminder of the sharp difference 際立った相違の象徴［を思い出させるもの］
pack送り出す
Perhaps more than any other insect, wasps are badly in need of a change in public opinion. As well as having fascinating lives, they are extremely important in the environment and face problems similar to those of their cherished, but often no less annoying, cousins the bees.
As the summer approaches its end, many will wish for it, but a world without wasps would most certainly not be a better place.
wish for  ～を望む、～を願う、～が欲しいと思う
Social types
The insects we most commonly identify as "wasps" are the social wasps. Social wasps (called yellow-jackets in some places) live in colonies consisting of hundreds or thousands of more-or-less sterile female workers and their much larger mother, the egg-laying queen.
The handful of colony-living, nest-building species is just a tiny fraction of overall wasp diversity, estimated at more than 9,000 species in the UK alone. Most wasps are solitary, some are tiny (a few species practically microscopic), none ever bother us and virtually all are overlooked.
Social wasp nests are constructed from wood fibres collected and then mixed with water by industrious wasp workers to make a kind of papier mache capable of producing very strong and long-lasting structures. The nests start to develop in late spring, when queen wasps emerge from hibernation.
Building a small nest of just a few paper cells, the queen must rear the first set of workers alone before the first batch of worker wasps can start to take over the work required by the developing colony.
Wasp workers toil ceaselessly to raise their sister workers from eggs the queen lays, cooperating and communicating in intricate ways to build and defend the nest, collect food and look after the queen. When the colony is large enough the workers start to give some young larvae more food at a much greater rate than usual, triggering genetic switches that cause the development of a potential queen rather than a worker.
Male wasps, who take no part in the social life of the colony, develop from unfertilised eggs in a form of sex determination called haplodiploidy, also found in bees and ants. 
haplodiploidy半倍数体、雄産性単為生殖
単為生殖とは、一般には有性生殖する生物で雌が単独で子を作ることを指す。
単為生殖によって産まれる子の性が、雌のみならば産雌単為生殖、雄のみならば産雄単為生殖（ハチ、ハダニ等）、雄も雌も生産可能ならば、両性単為生殖と区別される。また、卵子が精子と受精することなく、新個体が発生することを単為発生と呼ぶ。
These male-destined eggs are laid by the queen and rarely by workers, some of whom retain the ability to lay eggs but lack the ability to mate.
Potential queens (called gynes before they head a colony) and males, sisters and brothers of the workers, are the reproductive future of the colony. Mating with males from other colonies, the gynes overwinter before starting a colony of their own the following spring.
Gyne女王バチや女王アリなど、昆虫の巣の中で生殖にかかわる唯一の雌の個体 
They may not make honey, but nonetheless wasps have just as fascinating social lives as the celebrated honeybee.
Wasps are also just important in the environment. Social wasps are predators and as such they play a vital ecological role, controlling the numbers of potential pests like greenfly and many caterpillars.
Indeed, it has been estimated that the social wasps of the UK might account for 14 million kilograms of insect prey across the summer. A world without wasps would be a world with a very much larger number of insect pests on our crops and gardens.
As well as being voracious and ecologically important predators, wasps are increasingly recognised as valuable pollinators, transferring pollen as they visit flowers to drink nectar. It is actually their thirst for sweet liquids that helps to explain why they become so bothersome at this time of year.
voracious【形】 食欲旺盛な、貪り［ガツガツ］食う
By late August, wasp nests have very large numbers of workers but they have stopped raising any larvae. All the time, nests have larvae the workers must collect protein, which accounts for all those invertebrates they hunt in our gardens. The larvae are able to convert their protein-rich diet into carbohydrates that they secrete as a sugary droplet to feed the adults.
With no larvae, all those adult wasps must find other sources of sugar - hence why they are so attracted to our sugar-rich foods and drinks. When you combine that hunger for sugar with nice weather and our love of eating and drinking outside, the result is inevitable.
A new study is taking advantage of wasps' love of our drinks to find out more about these fascinating and undervalued insects. Calling on members of the public to help, the Big Wasp Survey is asking people to build a simple wasp trap from a drinks bottle and a small volume of beer.
Scientists from University College London (UCL) and the University of Gloucestershire want to collect and study the contents of these beer traps. The project, in conjunction with BBC's Countryfile and sponsored by the Royal Entomological Society, hopes to find out which species of wasps live where in the UK, and provide some baseline data for an annual Big Wasp Survey over the coming years.
As Dr Seirian Sumner (UCL) says: "The black and yellow wasps that bother us at picnics are social wasps and we would like to find out much more about where they live and how common they are; to do that we need the public's help".
Insects are generally having a hard time; changing environments, changing climate, habitat loss and the use of insecticides are all taking their toll on these vital creatures.
take a toll on ～に被害［損害］を与える、～に犠牲を強いる
Yet, whilst many take up the cause of the honeybee or extol the beauty of butterflies some of the most fascinating and important insects remain the most reviled. It's time we stopped asking "what is the point of wasps" and started to appreciate them for the ecological marvels that they are.
extol 【他動】〔人やものを〕褒めそやす、激賞する
take up the cause of peace 平和という大義に向かう［取り組む］
much-reviled 【形】 悪口の多い

20170827

Switzerland landslide: Are the Alps melting?
A massive rockslide in Switzerland's Val Bondasca was not a complete surprise. Many parts of Switzerland, two thirds of which is mountainous, are at risk of avalanches and landslides.
Communities in the Alps have been protecting themselves against such natural hazards for years.
Before Wednesday's landslide, sensors on the Piz Cenaglo, high above the Bondasca valley, had already shown that the rock mass was moving. That warning triggered the automatic closure of some sections of road.
The village of Bondo had a narrow escape. The four million cubic metres (141m cubic feet) of mud and rock which thundered down the mountain ended up just centimetres from people's homes.
That wasn't just luck. Bondo has a concrete barrier to protect it from the full force of a landslide, and the river bed in the Bondasca Valley has been widened in the hope of channelling landslides away from populated areas.
But the size of Wednesday's slide was a shock, and some scientists are now warning that the alpine regions can expect more events like this in the future.
Permafrost thaw
The reason is that the high mountains are not as cold as they once were. Marcia Phillips, a permafrost researcher with Switzerland's Federal Institute for Snow and Avalanche Research, has been analysing temperatures all over the Alps.
"We have bore holes at different depths in different terrain and the ones that are in rock walls are showing a distinct warming over the last 10 to 20 years," she explained.
That would not be a problem if the rock was simply rock, but the rock in large sections of the Swiss Alps is cracked and fractured - between the layers of rock there are layers of permafrost. Ice in fact, but ice that is not supposed to melt.
borehole 【名】 掘削孔
"We have a problem if the temperature rises above -1.5C because the permafrost has a stabilising function," Ms Phillips said.
Compounding the weakening permafrost is another phenomenon associated with global warming - Switzerland's glaciers are noticeably retreating.
compound【他動】～を構成する
The glacier at the base of Piz Cenaglo provided additional stability to the rock above it, but that glacier has shrunk in recent years. So precarious had the mountain become that Marcia and her colleagues had given up on borehole testing and instead resorted to remote monitoring.
precarious  【形】不安定な
"It is cracked and unstable up there," she explained, "It was just too dangerous."
Infrastructure fears
Another headache associated with thawing permafrost is the possible risk to winter tourism. The stanchions of cable cars and chairlifts are very often anchored in permafrost.
stanchion 【他動】 ～を支柱で支える
The Swiss government already requires intensive monitoring of cable car infrastructure. Lift operators must check regularly for any movement or creep.
Marcia Phillips suggests that, if temperatures do continue to rise, changes may have to be made.
"I could foresee some having to be closed down or rebuilt," she said.
In preparation, the avalanche institute has already produced a book "Building in Permafrost" with guidelines on how to build safely.
"It is possible but very, very expensive," said Ms Phillips.
That is not good news for Switzerland's tourism resorts, already suffering financially because of the strength of the Swiss franc.
For now, though, the focus remains on finding the eight people still missing from Wednesday's landslide, and on protecting those who live in the Bondasca Valley.
The residents of Bondo have been told they cannot go home yet. Four million cubic metres of rock came down but another million, very unstable, still looms above the village.
loom【自動】不気味に迫る

20170825

India swine flu death toll rises above 1,000 this year
swine flu豚インフル（エンザ）
ウイルスの種類は、オルトミクソウイルス科のC型インフルエンザウイルス（属）、およびA型インフルエンザウイルス（属） H1N1、H1N2、H2N1、H3N1、H3N2、H2N3などが確認されている。
2016 saw a dip in recorded deaths and affected cases, but this year they have risen.
India appears to be in the grip of a swine flu outbreak with 1,094 recorded deaths over the past eight months, said an official report on Wednesday.
dip下落、低下
in the grip of ～につかまれて、～に捕らえられて、～に支配されて
The last three weeks have seen the highest number of fatalities, at 342.
A total of 22,186 cases have been reported across the country.
The number of deaths this year is four times more than fatalities recorded over the equivalent period in 2016, which itself saw a dip in occurrences of the disease.
The western state of Maharashtra is the worst affected, where the death toll stands at 437, according to data revealed by the Union Health Ministry. Neighbouring Gujarat follows closely with 297 deaths, reported news agency PTI.
India experienced a severe swine flu wave two years ago, when health officials scrambled to contain an outbreak which killed more than 1,900 people. While 2016 saw a dip in recorded deaths (265) and affected cases (1,786), the numbers for this year indicate a resurgence of the disease.
The country saw its most crippling outbreak in the pandemic years of 2009-2010, when the virus affected around 50,000 people and claimed the lives of more than 2,700 across the country.
cripple【他動】不自由にする、不具にする～を活動不能にする、無能にする  〔機能を〕損なわせる
Dr Sanjay Gururaj, medical director at Shanthi Hospital, a private clinic, told the BBC that it was not mandatory for a private hospital to report its numbers to the government's database. "The numbers in the official report are possibly just the tip of the iceberg," he said.
mandatory 【形】義務的な、強制的な、職権で命ぜられた 統治を委任された
What is swine flu?
A respiratory disease caused by a strain of the influenza type A virus known as H1N1
Originated in pigs, but is now a human disease spread by coughing and sneezing
Symptoms similar to those produced by standard, seasonal flu - fever, cough, sore throat, body aches and chills
Vulnerable groups include pregnant women, children under five, the over-65s and those with serious medical conditions
The virus first appeared in Mexico in 2009 and rapidly spread around the world.
 

20170824

'Cyborg' bacteria deliver green fuel source from sunlight
cyborg 【名】 サイボー
Scientists have created bacteria covered in tiny semiconductors that generate a potential fuel source from sunlight, carbon dioxide and water.
The so-called "cyborg" bugs produce acetic acid, a chemical that can then be turned into fuel and plastic.
In lab experiments, the bacteria proved much more efficient at harvesting sunlight than plants.
The work was presented at the American Chemical Society meeting in Washington.
Researchers have been attempting to artificially replicate photosynthesis for many years.
Solar panel bugs
In nature, the green pigment chlorophyll is key to this process, helping plants to convert carbon dioxide and water, using sunlight, into oxygen and glucose.
But despite the fact that it works, scientists say the process is relatively inefficient. This has also been a big problem with most of the artificial systems developed to date.
This new approach seeks to improve that efficiency by essentially aiming to equip bacteria with solar panels.
After combing through old microbiology literature, researchers realised that some bugs have a natural defence to cadmium, mercury or lead that lets them turn the heavy metal into a sulphide which the bacteria express as a tiny, crystal semiconductor on their surfaces.
literature文献
sulfide 【名】 《化学》硫化物
"It's shamefully simple, we've harnessed a natural ability of these bacteria that had never been looked at through this lens," said Dr Kelsey Sakimoto from Harvard University in Massachusetts, US.
"We grow them and we introduce a small amount of cadmium, and naturally they produce cadmium sulphide crystals which then agglomerate on the outsides of their bodies."
shamefully 【副】 恥ずかしくも
harness 【他動】装具を付ける〔自然力を〕役立てる、生かす、用いる、利用する
agglomerate【自他動】 塊にする［なる］
"You grow them in their liquid broth and you just add small aliquots of cadmium solution and you wait a couple of days and out pops these photosynthetic organisms.
broth 【名】〔肉・魚・野菜などを煮出した〕だし汁、スープ 培養液
aliquot  【他動】〔数量を〕等分する【名】《数学》約数 《化学》アリコート、一定分量
"It's all very simple, mix-in-a-pot-chemistry."
These newly boosted bacteria produce acetic acid, essentially vinegar, from CO2, water and light. They have an efficiency of around 80%, which is four times the level of commercial solar panels, and more than six times the level of chlorophyll.
"We prize these cyborg bacteria and their ability to make acetate because they produce a substrate that we can already use to produce more valuable and more interesting products," said Dr Sakimoto.
 substrate【名】《生化学》基質
"We have collaborators who have a number of strands of E. coli that are genetically engineered to take acetic acid as their food source and they can upgrade it into butanol and a polymer called polyhydroxybutyrate."
ポリヒドロキシ酪酸（polyhydroxybutyrate; PHB）
Dr Sakimoto believes that these bacteria offer some advantages over other approaches to generating green energy from biological sources.
Other techniques for artificial photosynthesis require expensive solid electrodes.
The cyborg bug approach really only needs large vats of liquid to be kept out in the Sun - the bacteria are self-replicating and self-regenerating, making it potentially a low waste technology. It might work best in rural areas or in the developing world.
The research work was carried out at the University of California, Berkeley in the lab of Dr Peidong Yang.
"The thrust of research in my lab is to essentially 'supercharge' non-photosynthetic bacteria by providing them energy in the form of electrons from inorganic semiconductors, like cadmium sulphide, that are efficient light absorbers," Dr Yang said.
supercharge 【他動】過給する
"We are now looking for more benign light absorbers than cadmium sulphide to provide bacteria with energy from light."
The researchers believe that while their approach has taken an important new step, it might not ultimately be the technology that prevails.
"There are so many different designs of these systems coming out and really we've only begun to explore the different ways we can combine chemistry and biology," said Dr Sakimoto.
"And there's a real possibility that that there will be some upstart technology that will come out that will do better than our system."
upstart【形】   成金の、最近になって出現［発生］した、新しく起こった

20170822

Matt Dawson: I had to have heart surgery after a tick bite
When former England rugby player Matt Dawson was bitten by a tick in a London park early last year, it caused a bacterial infection to spread through his body.
"I had two days where I felt awful. Very feverish, on the sofa, crashed out," he said.
crash out【句動】寝入る
Eventually he went to hospital where he was diagnosed with Lyme disease:
Lyme disease
《病理》ライム病 マダニに媒介されるスピロヘータの一種、ボレリア Borrelia の感染によって引き起こされる人獣共通感染症の1つ。主にクロアシダニ（black-legged tick）がシカや野ネズミなどからボレリア菌（borrelia）を媒介して引き起こす感染症。ライム病を起こすボレリア菌は12種類が知られている。感染すると発しんができてインフルエンザに似た症状が現れ、その後さまざまな神経症状、関節炎、心筋炎などが発症、治療をしなければ慢性になる。【語源】1970年代半ばに最初に病気が報告されたコネティカット州の町Old Lymeから。マダニの咬着より数日から数週間後に、刺咬部を中心とした特徴的な遊走性紅斑を呈する。
"It was a really scary time for me and my family. Such a tiny creature caused me to end up needing heart surgery."
Lyme disease is a bacterial infection, passed on to humans by infected ticks.
end up 【句動】《end up （by） doing》結局［最後には］～になる［～することになる・～する羽目になる］
While it is difficult to estimate the total number of UK cases, they are understood to have increased more than fourfold in the past 10 years.
The peak season is April to October, though they are active all year round.
How can I spot the symptoms of Lyme Disease?
A distinctive rash called erythema migrans often develops after the tick bite
In around two-thirds of cases, a distinctive rash called erythema migrans will develop in the days to weeks that follow the tick bite
erythema migrans  遊走性紅斑
It is often shaped like a bullseye, but not in all cases, and some individuals will have several rather than one
Flu-like symptoms are another strong indicator of Lyme disease
Facial palsy is common in children
Others may experience tingling or numbness in parts of the body and, rarely, severe headaches
tingling 【名】チクチク感
If you get these symptoms and have also been bitten by a tick - or been out in a tick hotspot - then it is worth talking to your doctor
hot spot  人気のある場所
If left untreated, early localised Lyme can attack the nervous system and cause debilitating neurological problems
However, if you receive prompt antibiotic treatment, it can successfully treat the disease and prevent further illness
debilitate 【他動】 〔人や組織などを〕衰弱［消耗］させる
Source: BBC Trust me I'm a Doctor
A World Cup winner in 2003, Dawson played 77 times for England and made seven appearances for the British and Irish Lions.
Matt said he was floored by his diagnosis: "I'd heard of Lyme disease before. It was something I'd always associated with places abroad, on the continent, in America, wherever there were deer.
"There's no way that I would've walked through a wood or a forest with my kids and gone back home and thought, 'right, I'll just check for some ticks just to make sure everything is fine'. I just wouldn't have thought of that.
there's no way that   〔that以下〕なんて絶対に嫌だ［あり得ない］
How you get Lyme disease
Ticks can be found in areas with deep or overgrown vegetation.
They're common in woodland and heath areas, but can also be found in gardens or parks.
People who hike and camp in such places are at risk of getting bitten.
Ticks don't jump or fly, but climb on to your clothes or skin if you brush against something they're on. They then bite into the skin and start to feed on your blood.
It's thought only a small proportion of ticks carry the bacteria that cause Lyme disease, so being bitten doesn't mean you'll definitely be infected.
Pets can also bring ticks home in their fur.
Matt Dawson has now joined forces with The Big Tick Project, which looks to raise awareness about the dangers of ticks and tick-borne disease in the UK.
Tied to researchers at University of Bristol, the project has conducted the largest ever study of ticks in dogs. They studied 14,000 dogs from 1,400 vets across the UK and found almost one-third were carrying a tick.
TV presenter and naturalist Chris Packham is working with the project to raise awareness among pet owners and vets:
"It is really important that pet owners understand how they can treat their pets for ticks and reduce the risk of the further spread of these horrible, debilitating and potentially dangerous diseases to the UK," he said.
After multiple heart operations and 18 months of treatment, Matt no longer has the disease.
But it still affects his life: "I'm still on medication and its going to take a lot of time for the heart to fully recover.
"This is not something that should be looked at like, 'oh it's only a tick, a tick is a bit like a flea, its fine!'," he said.
"These ticks carry some really quite potent, serious bacteria and they can cause you a lot of problems. Raising awareness of them is imperative."
imperative 【形】 必要不可欠の、必須の 高圧的な、威圧的な
 

20170820

'Fat but fit' still risk heart disease
fit健康な、元気な、壮健な
People who are overweight or obese are at increased risk of heart disease even if they appear medically healthy, experts are warning.
The work, in the European Heart Journal, is further evidence against the idea people can be "fat but fit".
The researchers studied health data on more than half a million people in 10 European countries, including the UK.
Normal blood pressure, cholesterol and blood sugar levels were no assurance of good heart health among obese people.
assurance of 保障
After a follow-up period of more than 12 years, 7,637 of the people in the study had developed heart disease.
Weight appeared to be a risk factor.
In the study, people who were overweight or obese but had healthy blood pressure, blood sugar and cholesterol readings were about 28% more likely to develop heart disease than individuals with similar readings and a healthy bodyweight.
Being fat and "metabolically unhealthy" - having high blood pressure, cholesterol and blood sugar - was riskier still.
Are you a healthy weight for your height?
The researchers at Imperial College London and the University of Cambridge say the findings are a reminder that carrying too much fat can store up health problems for the future.
store up f蓄える
Dr Ioanna Tzoulaki, from Imperial's School of Public Health, said: "I think there is no longer this concept of healthy obese.
"If anything, our study shows that people with excess weight who might be classed as 'healthy' haven't yet developed an unhealthy metabolic profile.
if anything  どちらかといえば、それどころか
"That comes later in the timeline, then they have an event, such as a heart attack."
According to the researchers, the excess weight itself may not be increasing the risk of heart disease directly, but rather over time through mechanisms such as increased blood pressure and high glucose.
Prof Metin Avkiran, from the British Heart Foundation, which part-funded the research, said: "The take-home message here is that maintaining a healthy body weight is a key step towards maintaining a healthy heart."
take-home message 覚えておいてほしいこと、〔家庭に持ち帰ってほしいほど〕重要なこと

20170819

Freeze-dried dung gives clue to Asian elephant stress
"Collecting fresh faecal samples is not as easy as it may sound," says researcher Sanjeeta Sharma Pokharel.
But her efforts have helped scientists in India devise a unique, non-invasive way to monitor the physiological health of wild elephants.
The key has been freeze-drying dung in the field to preserve the elephant's hormones.
As a result, scientists found stress levels in females were more conspicuous than in male elephants.
Over five years, Sanjeeta and her colleagues collected more than 300 samples from 261 elephants in the biodiversity-rich Western Ghats area.
She explained her technique: "I used to hide and observe till the elephant defecated and moved away."
She told the BBC: "These samples mean a lot to me."
The aim of the research was to evaluate the influence of the elephants' body condition on glucocorticoid metabolites.
glucocorticoid 【名】グルココルチコイド、糖質コルチコイド
糖質コルチコイド（とうしつコルチコイド）は、副腎皮質の束状層で産生される、副腎皮質ホルモンの一つである。
タンパク質を糖化(糖に変換（脱アミノ基））して、血糖量を上昇させる。 また、グルカゴン、アドレナリンに対する許容作用がある。 糖質コルチコイドが存在しないと、これらのホルモンの働きが起きない。
中枢神経に対しては成長ホルモン分泌抑制を、肝臓に対してはインスリン様成長因子発現抑制をもたらし、全身での細胞増殖・成長を抑制する。医薬品として使われる。抗炎症効果や免疫抑制効果がある。
subjected to  《be ～》～に従う、～を被りやすい、～にさらされる、～を受ける
Animals such as elephants are subjected to various stressors in their lives, with factors including threats from predators, food shortages, drought and illness.
Whenever any animal faces stressful events, their body secretes hormones known as glucocorticoids.
These hormones are released into the circulatory system which eventually breaks them down into metabolites that are excreted through urine or faeces.
The researchers say that collecting blood samples to assess stress levels is neither ethical nor feasible, since immobilising the animals will cause additional stress, thus biasing the study.
"So glucocorticoid was measured using faecal or dung samples," said Sanjeeta.
The team found the glucocorticoid metabolites in the dung remained relatively stable up to six hours after defecation, though collecting samples as fresh as possible was preferred.
After six hours the dung starts to degrade through microbial activity. To prevent this, the collected samples were freeze-dried in the field and stored at -20 degrees Celsius for further analysis.
Stress levels for all elephants peaked during the dry season, when resources were low.
Senior researcher Prof Raman Sukumar said: "In a natural environment, large and long-ranging herbivorous mammals such as elephants may have to face various ecological challenges or stressful conditions.
"One such challenge that might impact their health is forage resource limitation, either in terms of quality or quantity."
Higher amounts of glucocorticoids generally indicated that the animal was more stressed, he said.
"Stress levels in female elephants were more conspicuous than in male elephants."
All mammalian systems would show a similar trend, the researchers say.
mammalian【名】 哺乳類の動物
Dr Sukumar and his team claim that their study is the "first to examine the relationship between body condition, seasonality and stress in wild Asian elephants using large-scale faecal sample collection for assaying glucocorticoid metabolites".
The study also focused on finding possible answers to how elephant populations react to chronic stress and if superior nutrition from feeding on cultivated crops could help them reduce their physiological stress levels that may otherwise be enhanced through harassment by farmers trying to protect their fields.
They also examined the idea that body condition alone could act as an indicator of physiological health and fitness of an animal.
In the study, the animal's body condition was scored on a scale from one to five, with one indicating the animal was in a very poor state and five indicating the animal was obese.
The study conclusively found that the stress levels in the Asian elephants peaked during the dry season when resources were low. They also concluded that very poor or poor body condition was a good visual indicator of stress.
The research has been published in the Oxford Journal Conservation Physiology.

20170818

Peanut allergy treatment 'lasts up to four years'
An oral treatment for peanut allergy is still effective four years after it was administered, a study has found.
Children were given a probiotic, with a peanut protein, daily for 18 months.
probiotic【名】 体に良い（働きをする）バクテリア［細菌］腸内フローラのバランスを改善し、カラダによい作用をもたらす生きた微生物。
When tested one month later, 80% could tolerate peanuts without any allergic symptoms and after four years, 70% of them were still able to eat peanuts without suffering any side-effects.
Food allergies have risen dramatically in recent decades, with peanut allergy one of the most deadly.
Lead researcher Prof Mimi Tang, of Murdoch Childrens Research Institute in Melbourne, said half the children were consuming peanuts regularly while others were only eating them infrequently.
"The importance of this finding is that these children were able to eat peanuts like children who don't have peanut allergy and still maintain their tolerant state, protected against reactions to peanuts," she said.
Prof Tang said it was the first time a treatment for peanut allergy had been shown to be effective for this long.
The probiotic used is called Lactobacillus rhamnosus, which has been associated with preventing certain allergic symptoms.
ラクトバチルス・ラムノサス 乳酸菌の1種  代表的な乳酸かん菌で、整腸作用があります。
The Australian research team now wants to assess whether the treatment has improved the children's quality of life, as some 250 million people worldwide are affected by food allergy - a number which has more than trebled in the last 20 years.
Peanut allergy, which is one of the most common causes of death from food allergy, has increased at the greatest rate.
Prof Tang said the findings, published in The Lancet Child & Adolescent Health, suggest "the exciting possibility that tolerance is a realistic target for treating food allergy".
She added: "This is a major step forward in identifying an effective treatment to address the food allergy problem in Western societies."

20170817

Plants 'hijacked' to make polio vaccine  By James Gallagher 
A close relative of tobacco has been turned into a polio vaccine "factory"
Plants have been "hijacked" to make polio vaccine in a breakthrough with the potential to transform vaccine manufacture, say scientists.
The team at the John Innes Centre, in Norfolk, says the process is cheap, easy and quick.
As well as helping eliminate polio, the scientists believe their approach could help the world react to unexpected threats such as Zika virus or Ebola.
Experts said the achievement was both impressive and important.
The vaccine is an "authentic mimic" of poliovirus called a virus-like particle.
Outwardly it looks almost identical to poliovirus but - like the difference between a mannequin and person - it is empty on the inside.
thentic mimic 本物の物まね
on the inside内から、内側に［で］
It has all the features needed to train the immune system, but none of the weapons to cause an infection.
The scientists hijacked a relative of the tobacco plant's metabolism to turn its leaves into polio-vaccine "factories".
First, they needed to create new instructions for the plant to follow.
The starting material was the genetic code for making the outer surface of poliovirus.
It was enhanced by combining it with material from viruses that naturally infect plants.
The new instructions were then put into soil bacteria, which were used to infect tobacco.
soil bacteria  土壌中のバクテリア
The infection took hold, the plants read the genetic instructions and started making the virus-like particles.
Infected leaves were mixed with water, blended, and the polio vaccine was extracted.
take hold 根付く
The virus-like particles prevented polio in animal experiments, and an analysis of their 3D structure showed they looked almost identical to poliovirus.
Prof George Lomonossoff, from the John Innes Centre, told the BBC News website: "They are incredibly good mimics.
"It's a very promising technology,
"I would hope we get vaccines produced in plants in the not too distant future."
The research is funded by the World Health Organization, as part of efforts to find replacements for the polio vaccine.
Polio - which can cause permanent paralysis - is a thing of the past for most of the world, but the infection has not been eradicated.
And using weakened poliovirus in current vaccines poses a risk of the virus regaining some of its dangerous traits - called vaccine-derived poliovirus.
vaccine-derived poliovirusワクチン由来ポリオウイルス
伝播型ワクチン由来ポリオウイルスは、経口生ポリオワクチン接種者自身あるいは地域集団で経口生ポリオワクチン株が長期間増殖・伝播することにより遺伝子変異を蓄積した経口生ポリオワクチン由来変異株であり、遺伝子変異や他のエンテロウイルスとの遺伝子組換えにより、病原性や伝播能等、野生株ポリオウイルスと同等のウイルス表現型を獲得する場合がある。
Dr Andrew Macadam, principal scientist at the UK's National Institute for Biological Standards and Control, said: "Current vaccines for polio are produced from large amounts of live virus, which carries a threat of accidental escape and re-introduction.
"This study takes us a step closer to replacing current polio vaccines, providing us with a cheap and viable option for making virus-like particle-based vaccines."
viable option  実行可能な選択
But this technology is not limited to polio or even just to vaccines.
As long as researchers have the right sequence of genetic code, they can make a vaccine against most viruses.
And they have also used plants to make antibodies like those being used in cancer therapy.
抗腫瘍性抗生物質とも呼ばれています。土壌に含まれるカビなどから作られたもので、がん細胞の細胞膜を破壊したり、DNAまたはRNAの複製・合成を阻害します。
Plants are also being investigated as a new source for the winter flu jab.
Currently, it is grown in chicken eggs and takes months to develop.
Prof Lomonossoff told the BBC: "In an experiment with a Canadian company, they showed you could actually identify a new strain of virus and produce a candidate vaccine in three to four weeks.
"It has potential for making vaccines against emerging epidemics, of course recently we had Zika and prior to that we had Ebola.
"It's highly responsive, and that's one of the great attractions of the technology."
The plants have the advantage of growing quickly and needing only sunlight, soil, water and carbon dioxide to grow.
It means it could be a cheap and low-tech solution to vaccine development.
But there are still issues to resolve, including making vaccine on a large scale.
Another issue is whether there is any risk from using plants to make the vaccine - does the tobacco-relative mean there is nicotine in the vaccine?
Dr Tarit Mukhopadhyay, a lecturer in vaccine development at University College London, said: "The initial results look impressive.
"However, there are very few plant-based vaccine manufacturers and almost no licensed human vaccines that are currently produced in plants."
Denis Murphy, a professor of biotechnology at the University of South Wales, said: "This is an important achievement.
"The challenge is now to optimise the plant expression system and to move towards clinical trials of the new vaccine."
expression system 発現系

20170814

UK rations hepatitis B vaccine amid global shortage
ration 【他動】制限する 
UK health officials are putting a temporary limit on who can have a hepatitis B vaccination because stocks are running low.
The move is in response to the wider, global shortage of the jab caused by manufacturing issues.
jab【名】皮下注射、接種
UK travellers are being told they may not be able to get it before they leave Britain for higher-risk countries.
Babies and high-risk groups will be prioritised under the measures that are expected to continue into 2018.
A spokeswoman for Public Health England said: "All those who need to have a hepatitis B vaccine will be offered it in due course."
prioritize 【他動】  ～を優先する［させる］
in due course   そのうち、やがて
But she said some people wanting to be vaccinated now may not be able to have the jab.
Who needs a hepatitis B jab?
All UK infants should be vaccinated because the infection can persist for many years in children and can eventually lead to complications, such as scarring of the liver or liver cancer.
The chance of catching hepatitis B, which is spread by contact with infected blood and other body fluids, is very low in the UK.
scarring 【名】 傷、瘢痕化
But some people - those who inject drugs and share needles, for example - are at higher risk.
In some parts of the world, including East Asia and Sub Saharan Africa, the infection is more widespread.
The risk for travellers to such countries is still low, but people visiting these countries from the UK may still want to consider getting immunised.
Can I buy the vaccine?
The NHS does provide free doses, based on clinical need. Some people may be charged for the vaccine.
Private clinics may also have stock that they can offer patients for a fee.
The current global shortage is affecting stocks in private clinics as well as the NHS. Although manufacturers are getting more stock in, supplies are limited.
How else can I protect myself?
You can:
avoid having unprotected sex
avoid having tattooing, piercing and acupuncture in an unhygienic environment with unsterilised equipment
avoid exposure to contaminated needles (not sharing needles)
Travellers may also want to consider taking a sterile medical equipment kit if travelling to areas with poor resources.

​20170813

GM pigs take step to being organ donors
The most genetically modified animals in existence have been created to help end a shortage of organs for transplant, say US researchers.
The scientists successfully rid 37 pigs of viruses hiding in their DNA, overcoming one of the big barriers to transplanting pig organs to people.
The team at eGenesis admits preventing pig organs from being rejected by the human body remains a huge challenge
But experts said it was a promising and exciting first step.
The study, published in the journal Science, started with skin cells from a pig.
Tests identified 25 Pervs - porcine endogenous retroviruses - hidden in the pig's genetic code.
porcine endogenous retrovirus ブタ内在性レトロウイルス
ブタ内在性レトロウイルスがブタの臓 器の移植を受けた患者に感染し、患者に癌、免疫不全など思いがけない病気を起こす ことはないか 
ブタ内在性レトロウイルスはおそらく数百万年前にブタの染色体に組み込まれたも ので、ほとんどはウイルスの遺伝子の一部でいわばウイルスの化石のようなものです が、中には完全なウイルス遺伝子を保有していて感染性ウイルスを放出するものがあ ります。
Experiments mixing human and pig cells together showed those viruses could escape to infect human tissues.
But the researchers then used the game-changing gene-editing technology Crispr to delete the 25 Pervs.
It then took cloning technology, the same used to create Dolly the sheep, to place the genetic material from those cells into a pig's egg and create embryos.
The complex process is inefficient, but 37 healthy piglets have been born.
"These are the first Perv-free pigs," Dr Luhan Yang, one of the researchers from Harvard University and the spinout company eGenesis, told the BBC News website.
They were also "the most genetically modified [animals] in terms of the number of modifications", he said.
If xenotransplantation - using organs from other species - works, then it has the potential to alleviate long waits for a transplant.
More than 100,000 people need an organ transplant in the US. There are about 6,500 people on the UK waiting list.
Dr Yang told the BBC: "We recognise we are still at the early stages of research and development.
"We know we have an audacious vision of a world with no shortage of organs, that is very challenging, but that is also our motivation to remove mountains."
audacious【形】 大胆な、恐れを知らない 斬新な、独創的な
Pigs are particularly promising for xenotransplantation as their organs are a similar size to humans', and the animals can be bred in large numbers.
But removing the viruses is only half the challenge, even organs donated from other people can cause a strong immune reaction that leads to the transplant being rejected.
The US team is investigating further genetic modifications to make pig organs more acceptable to the human immune system.
Darren Griffin, a genetics professor at the University of Kent, said: "This represents a significant step forward towards the possibility of making xenotransplantation a reality.
"However, there are so many variables, including ethical issues, to resolve before xenotransplantation can take place."
Prof Ian McConnell, from the University of Cambridge, said: "This work provides a promising first step in the development of genetic strategies for creating strains of pigs where the risk of transmission of retroviruses has been eliminated.
"It remains to be seen whether these results can be translated into a fully safe strategy in organ transplantation."
The researchers had to overcome unexpected challenges from performing so much gene-editing in one go.
in one go   〔複数の動作・処理などが〕1回で   一気に
The Crispr technology works like a combination of a sat-nav and a pair of scissors. The sat-nav finds the right spot in the genetic code, and then the scissors perform the cut.
sat nav【略】 ＝satellite navigation  衛星ナビゲーション
But making 25 cuts throughout the pig's genome led to DNA instability and the loss of genetic information.

20170811

Egg scandal: 20 tonnes sold in Denmark, food agency says
Millions of eggs have now been withdrawn from shops in several European countries
Twenty tonnes of insecticide-tainted eggs have been sold in Denmark, the country's food safety authority says.
The boiled and peeled eggs were mainly sold to cafeterias, cafes and catering firms, the Danish Veterinary and Food Administration said in a statement.
Denmark is the latest European country to discover eggs contaminated with fipronil in its food chain.
The insecticide can damage people's kidneys, liver and thyroid glands if eaten in large quantities.
フィプロニル（英:fipronil）は、フェニルピラゾール系殺虫薬の1つ。神経伝達物質であるGABAの作用を阻害することによりノミ、ゴキブリ、アリ、アルゼンチンアリ、シロアリなどの駆除に使用される。遅効性の毒物であるため、混ぜたエサを摂食した昆虫が致死するまでに巣やコロニーに戻る時間余裕があることが特徴である。ゴキブリやアリの場合、その死骸やフンを摂食した巣の仲間にまで効力を発揮するため巣の集団全体へその効果が広がっていく。
However, the Danish food administration urged calm, saying the eggs bought by Danag Products posed no risk to human consumption.
"Samples analysed in the Netherlands show traces of fipronil in the eggs, but not as a health hazard," the agency said [in Danish]. "Because the content is illegal, Danag Products must withdraw the eggs from their customers."
Twenty tonnes is the equivalent weight of two-and-a-half African elephants.
Denmark is believed to be the tenth country affected by the widening scandal, with Romania and Luxembourg among the latest to report finding contaminated products.
The majority of the eggs have originated from the Netherlands, but also from Belgium and Germany.
Romanian authorities said on Thursday that one tonne of liquid egg yolk contaminated with fipronil had been found in a warehouse in the west of the country. 
The product was imported from Germany but had not been sold to consumers, food safety officials said.
It also emerged on Thursday that two managers at a Dutch company had been arrested during joint raids by Dutch and Belgian authorities.
The company - named as Chickfriend by local media - allegedly used fipronil at poultry farms, prosecutors in the Netherlands said.
Fipronil is banned from use in the food industry under EU rules.
In a statement, the prosecutors said investigators were also focused on a Belgian supplier, and another Dutch company "that colluded with the Belgian supplier".
collude with ～と共謀する
They added: "They are suspected of putting public health in danger by supplying and using fipronil in pens containing egg-laying chickens."
Chickfriend, a poultry farm cleaning company, is yet to comment.
Belgian firm Poultry Vision is alleged to have sold chemicals to Dutch company Chickfriend
Investigators in Belgium have also carried out several raids and identified 26 people or companies as suspects, Some 6,000 litres of "prohibited products" were seized in Belgium.
In the UK, the Food Standards Agency now says about 700,000 eggs have been imported from potentially contaminated Dutch farms, up from an early estimate of 21,000,
But it said it was very unlikely that there was a risk to public health.
However, 11 products containing egg - including sandwiches and salads - have been withdrawn from supermarkets.
The Netherlands is Europe's biggest egg producer - and one of the largest exporters of eggs and egg products in the world.
Some 180 farms - which produce millions of eggs a week - have been temporarily shut down while further tests are carried out.
It is thought that fipronil was added to an allowable treatment for red mites.
The problem first surfaced earlier in August, when Aldi withdrew all its eggs from sale in Germany.
It has since emerged Belgian officials knew about the contamination in June, but did not make the information public because of a fraud investigation.
But Belgium has in turn accused the Dutch of knowing about the problem as far back as November 2016, which they deny.
fraud investigation 詐欺の調査