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Evolution of China's flowering plants shows East-West divide between old, new lineages
Source: Xinhua| 2018-02-01 07:00:00|Editor: Liangyu


CHICAGO, Jan. 31 (Xinhua) -- There is a distinct regional pattern in China's 30,000 flowering plant species: Eastern China is a floral "museum" with a rich array of ancient lineages and distant relatives, while the western provinces are a "cradle" for newer and more closely related species.

In a study published Wednesday in the online edition of Nature, researchers from the Chinese Academy of Sciences, Hope College, the Florida Museum of Natural History, and the University of Michigan (UM) highlight the need for more conservation efforts in densely populated eastern China, home to many threatened plant species.

In the study, researchers produced the first dated phylogeny, a family tree of organisms showing when new species appeared, for all of China's flowering plant species, or angiosperms, and mapped their distributions using 1.4 million museum records.

The researchers found that about 66 percent of angiosperm genera in China did not originate until the early Miocene, about 23 million years ago. Mean species divergence times when species first appeared fell between 22-25 million years ago in the East and 15-19 million years ago in the West.

Over the past 30 million years, herbaceous plants, those without a woody stem, diversified much more quickly than woody genera such as shrubs, trees and vines.

China is home to about 10 percent of the world's flowering plant species, outstripping the number of angiosperm species in the U.S. by more than 3.5-fold. Its varied geography and climate contribute to its wealth of biodiversity.

Unlike North America and Europe, China did not undergo the dramatic ecological turnover driven by glaciation in the ice age from about 2.58 million to 11,700 years ago, thus allowing ancient plant lineages to persist in the East and newer lineages to be folded into ever-diversifying plant communities.

China didn't experience that big type of cataclysmic event, and that allowed it to be more of a museum than other parts of the Northen Hemisphere, said Doug Soltis, professor and curator at the Florida Museum of Natural History.

The uplift of the Qinghai-Tibetan Plateau in the West spurred the region's evolutionary explosion of new species by opening up myriad new habitats and creating a cool, arid western climate. The West became a cradle for newer herbaceous plants while the East remained a museum for older herbaceous plants and both a museum and a cradle for woody plants.

The researchers used species-distribution data to map China's areas of genetic richness, pinpointing several eastern provinces as home to the country's greatest genetic diversity of flowering plants: Guangdong, Guanxi, Guizhou, Hainan and Yunnan. Conservation in the East, however, is carried out on a much smaller, more fragmented scale than in the sparsely populated West.

The researchers pointed to the value of museum collections in enabling this country-scale study of thousands of plant species spanning millions of years of evolution. Each plant specimen, painstakingly collected and preserved in herbaria over the past century and digitized, contributed to an enormous dataset that offered a detailed snapshot of China's diversity of flowering plants.

"It is only the beginning, as we can now apply these methods across the globe and throughout the tree of life," said Stephen Smith, a UM evolutionary biologist and co-author of the study.

Li-Min Lu, Ling-Feng Mao, Tuo Yang, Jian-Fei Ye, Bing Liu, Hong-Lei Li, Miao Sun, Joseph T. Miller, Sarah Mathews, Hai-Hua Hu, Yan-Ting Niu, Dan-Xiao Peng, You-Hua Chen, Stephen A. Smith, Min Chen, Kun-Li Xiang, Chi-Toan Le, Viet-Cuong Dang, An-Ming Lu, Pamela S. Soltis, Douglas E. Soltis, Jian-Hua Li, Zhi-Duan Chen. Evolutionary history of the angiosperm flora of China. Nature, 2018; DOI: 10.1038/nature25485

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Evolutionary history of the angiosperm flora of China | Nature Ecology & Evolution Community
 
Prehistoric 'pancake bird' sheds light on ancient avians
2018-02-02 21:20 GMT+8

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The remains of a prehistoric bird dating back some 100 million years were discovered inside a piece of Burmese amber.

The finding was announced on Friday in Beijing by paleontologists from China, Canada, and the United States.

Similar in size to the smallest modern bird – the bee hummingbird – the 5 cm bird is well preserved in the piece of amber. The remains, dating from the late Cretaceous period, feature "skeletal material and soft tissues in unmatched detail," according to an academic paper published as the cover article of the journal Chinese Science Bulletin.

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A reconstructed picture of the "pancake bird" /Photo via people.cn

Professor Tseng Kuowei at the University of Taipei noted that the specimen provides a unique perspective for research as it is split along the coronal plane, exposing much of its internal anatomy and giving it the nickname "pancake bird".

Although parts of the skull and most of the right wing and leg are missing, it is still the most complete prehistoric bird specimen found in Burmese amber so far, according to Jingmai O'Connor, a researcher at the Institute of Vertebrate Paleontology and Paleoanthropology in China.

Based on the latest study, the bird's skeletal structure and plumage patterns are basically in alignment with those of the enantiornithines.

Enantiornithes first appeared in the Cretaceous period and died out at the same time as their non-avialan dinosaur relatives. The extinct avialans were one of the most crucial branches in the evolution of ancient birds.

"The density and length of the feathers preserved along the exposed neck and head regions may suggest that this specimen is older than a hatchling or the juvenile remains discovered in the area," said Xing Lida, associate professor at China University of Geosciences.

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Close up of the wing /Photo via people.cn

"So far, this pancake bird is the most physically developed ancient bird ever discovered in amber," Xing said.

Moreover, structures found in its primary feathers indicated the rigid feathers were capable of flight, making them more consistent with feathers from advanced flying birds than typical enantiornithines.

It is not clear whether the bird was alive when it was sealed in resin. The missing internal organs and lack of soft tissue around the femur suggest it might have died before it was trapped in the amber.

Paleontologists believe that further studies of the specimen will shed light on the process of corpse preservation, as well as the diversity and geographical distribution of ancient birds.

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Chinese scientists discover spider with a tail trapped in 100 million-year-old amber
2018-02-06 14:42 GMT+8


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Two teams of scientists on Monday unveiled a "missing link" species of spider with a scorpion-like tail found perfectly preserved in amber in Southeast Asia's forests after at least 100 million years.

In studies published side-by-side in Nature Ecology and Evolution, one team argued that male sex organs and silk thread-producing teats link the creature to living spiders.

The other team pointed to the long tail and a segmented body to argue that Chimerarachne yingi belongs instead to a far more ancient and extinct lineage at least 380 million years old.

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An extraordinary new species of arachnid, resembling a spider with a tail, has been discovered in amber from Myanmar of mid-Cretaceous age, around 100 million years ago. /Photo via University of Kansas

Either way, the researchers agree that C. yingi fills a yawning gap in the evolutionary saga of the nearly 50,000 species of spiders that spin webs and trap prey around the world today.

"It's a missing link between the ancient Uraraneida order, which resemble spiders but have tails and no silk-making spinnerets, and modern spiders, which lack tails," said Bo Wang, a palaeobiologist at the Chinese Academy of Sciences in Nanjing and lead author of the study, suggesting C. yingi has more in common with their present-day, eight-legged cousins.

Remarkably, the previously unknown species was simultaneously discovered by two groups of scientists, each of which unearthed two specimens locked in translucent amber teardrops.

By coincidence, both teams submitted their findings to the same journal, which coordinated the joint release.

With a total body length of about six millimeters (one-fifth of an inch) – half taken up by the tail – C. yingi is, truly, an itsy bitsy spider.

The filaments made by four nipples extruding from the back end of its abdomen were probably not there to spin webs, the researchers speculated.

Venom glands

"Spinnerets are used to produce silk for a whole host of reasons: to wrap eggs, to make burrows, to make sleeping hammocks, or just to leave behind trails," said Paul Selden, Wang's co-author and a professor at the University of Kansas.

C. yingi also boasts pincer-like appendages, called pedipalps, used to transfer sperm to the female during mating, a signature trait of all living spiders.

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AFP Photo

Its whip-like tail or flagellum, also known as a telson, likely "served a sensory purpose," Wang told AFP.

By contrast, modern spiders use silk spun into webs to monitor changes in their surroundings.

They also have venom secreted from special-purpose glands, but neither of the studies was able to confirm that C. yingi could poison its prey.

Both teams used X-ray computed tomography scanning technology to remotely dissect their specimens.

The new species was discovered in the jungles of Myanmar, which yields nearly 10 tonnes of amber every year.

"It has been coming into China where dealers have been selling to research institutions," Wang said.

Amber has been crucial for tracing the early ancestors of spiders – but only up to a certain point.

"Spiders have soft bodies and no bones, so they don't fossilize very well, so we rely on special conditions – especially amber – to find them," Wang explained.

But working back in time, the trail of animal remains in amber ends about 250 million years ago, making it very difficult to trace the spider's earliest origins.

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Lunar Eclipse Of A Super Blue Blood Moon


Total Lunar Eclipse

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▲ Taken by Steed Yu on January 31, 2018 @ Beijing, China

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the begin (, maximum, and end ) of the super blue total lunar eclipse in Jan. 31st, 2018

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Super Blue Blood Moon&aircraft

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▲ Taken by cat on January 31, 2018 @ nanjing,china

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Super moon + blue moon + red moon + plane, this is a rare opportunity. At that time I was watching with friends in the square and took pictures with the camera in my hand. It was just a plane coming over. My feeling was that the plane could pass through the moon, so I quickly picked up the camera in my hand and kept pressing the shutter button. Finally, the plane and the moon freeze in the camera screen. This picture is so exciting, how good luck can meet. awesome!

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Lunar Eclipse

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▲ Taken by Steed Yu on January 31, 2018 @ Beijing, China

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We can see the shadow of the Earth, when the Lunar eclipse happens.

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Super Blue Blood Moon&earth Shadow

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▲ Taken by janewind on January 31, 2018 @ nanjing,china

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This is the most beautiful total lunar eclipse Ive ever seen. The blue moon, the red moon and the super moon are great. Most of the total solar eclipse seen on the horizon was on the horizon. The total eclipse was at high altitude this time. More than a thousand people, the atmosphere is great. The weather was not very good on that day, and my friend said I might not see it. I told her that if I could not see it, I would take the moon off and I prepared a 3D printed moon lantern I made myself. That night, when I took out the glowing Moon model, we became the focus, and everyone came around for a group photo and attracted a reporter from Shanghai Oriental Satellite TV to come to interview. The red moon that day, simply beautiful, too unforgettable!

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:enjoy:
 

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PUBLIC RELEASE: 9-FEB-2018
Chinese researchers report first lung stem cell transplantation clinical trial
SPRINGER

A research team from Tongji University in China have made a breakthrough in human lung regeneration technology. For the first time, researchers have regenerated patients' damaged lungs using autologous lung stem cell transplantation in a pilot clinical trial. The study can be found in the open access journal Protein & Cell which is published by Springer Nature.

For patients suffering from chronic pulmonary diseases, lung stem cell transplantation could be their biggest, if not last, hope.

"Both patients and researchers need great courage to step forward from benchside to bedside, to test the new therapeutic strategy. Now the good news is that the strategy looks quite promising," said author of the study, Professor Wei Zuo.

Already in 2015, Professor Zuo and his colleagues identified p63+/Krt5+ adult stem cells in a mouse lung, which had potential to regenerate pulmonary structures including bronchioles and alveoli. Now Professor Zuo's lab in Tongji University and Kiangnan Stem Cell Institute is focusing on lung stem cells in humans rather than mice.

"The anatomical structure and development process of human lungs are quite different from that of mice. Only by directly studying human subjects can we get close to the truth and finally solve the real medical problem," Zuo explained.

The researchers found that a population of basal cells labeled with an SOX9+ marker had the potential to serve as lung stem cells in humans. By working with Ren Tao, professor and physician in Shanghai East Hospital, they used lung bronchoscopy to brush off and amplify these lung stem cells from tiny samples. About 0.2% of the cells from each brush were lung stem cells. The genetic stability and molecular phenotypes of these cells could be well maintained over scaled expansion.

In order to test the capacity of lung stem cells to regenerate lung tissue in vivo, the team transplanted the GFP-labeled human lung stem cells into damaged lungs of immunodeficient mice. Three weeks after transplantation, they detected that human lung stem cells were integrated into mice lungs in a large area, forming a "human - mouse chimeric organ".

Further histological analysis showed that stem cell transplantation successfully regenerated human bronchial and alveolar structures in the lungs of mice. More importantly, the host capillaries rose around the regenerated human alveoli structures, which indicated the formation of functional respiratory units as demonstrated by the gold nanoparticle tracking technique. Also, the fibrotic area in the injured lungs of the mice was replaced by new human alveoli after receiving stem cell transplantation. Arterial blood gas analysis showed that the lung function of the mice was significantly recovered

Together with researchers from Southwest Hospital of China Army University and Regend Therapeutics, the team launched the first clinical trial based on autologous lung stem cell transplantation for the treatment of bronchiectasis. Bronchiectasis is a permanent injury to the bronchial structure of lung. After strict review by academic and ethical committees, the first two patients were recruited in March 2016. Their own lung stem cells were delivered into the patients' lung through bronchoscopy.

One year after transplantation, two patients described relief of multiple respiratory symptoms such as coughing and dyspnea. CT imaging showed regional recovery of the dilated structure. Patient lung function began to recover three months after transplantation, which maintained for one year.

"Stem cell transplantation is quite effective and we will continue the study by expanding the cohort size, including the control group and carrying out a long-term continuous observation," said Professor Xiaotian Dai, the physician who supervised this clinical study.

The safety and efficacy of cell therapy depends largely on the cell quality.

"Quality is life and we are implementing the quality management strictly according to the CFDA standard of China as well as the FDA standards of the United States," said Lifeng Wang, the chief quality officer of Regend Therapeutics .

According to Professor Wei Zuo, the lung stem cell clinical trial in China has been licensed by CFDA and National Health and Family Planning Commission. A multi-center, placebo-controlled study is being carried out. Up to now, the team has performed 80 stem cell transplantation cases in total, involving different categories of respiratory diseases including bronchiectasis, chronic obstructive pulmonary disease and interstitial lung disease.

"Chronic lung diseases could be conquered within 5 years," said Professor Zuo.

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Reference: Ma Qiwang et al (2018). Regeneration of functional alveoli by adult human SOX9+ airway basal cell transplantation, Protein & Cell DOI: 10.1007/s13238-018-0506-y


Chinese researchers report first lung stem cell transplantation clinical trial | EurekAlert! Science News
 
Breakthrough may help with earlier detection of heart attacks and cancer

2018-02-12 09:45 Xinhua Editor: Gu Liping

A mobile phone-sized box may help patients detect acute heart failure or cancer, at any time, without any medical assistance. A Chinese research program is trying to make this "family physician" dream come true.

Chinese scientists have developed a biosensor based on an optical microfiber coupler (OMC) to identify one ultra sensitive biomarker of acute myocardial infarction (AMI), the medical term for a heart attack, which could make detection much easier and less expensive.

A team of scientists from Changchun Institute of Optics, Fine Mechanics and Physics (CIOFMP) under the Chinese Academy of Sciences have dedicated 16 years to researching this label-free immunosensor and published their findings online in the scientific journal, Biosensors and Bioelectronics earlier this month.

"The goal of this research is to make detection of heart attack biomarkers more sensitive and convenient, so as to identify the disease at an earlier stage," said Zhou Wenchao, a researcher at the CIOFMP State Key Laboratory of Applied Optics.

Despite advancements in modern medicine, heart attacks remain a common, life-threatening condition.

According to Zhou, early diagnosis can decrease the fatality rate of heart attacks. However, patients can currently only go to hospitals for testing, instead of testing themselves at home.

Hospitals usually use a biochemical technique called enzyme immunoassay (EIA) to track AMI biomarkers, which takes one to two hours for one single test and requires a 0.1 ng/ml clinical cut-off.

Chinese researchers are trying to improve the situation by developing the OMC. "Since 2002, we've recorded countless failures while trying to find the way to improve the test sensitivity and accuracy, and maintain its stability. Now each test only takes 10 minutes and costs less than the EIA approach," said Wu Yihui, head researcher in the program at the State Key Laboratory of Applied Optics.

In experiments, the sensitivity of this newly-developed biosensor can reach to 2 fg/ml, equivalent to a 0.000002 ng/ml cut-off.

The research is jointly sponsored by the China-Israel International Science and Technology Cooperation Program and the National Natural Science Foundation of China.

"The research has put forward an approach that can improve the sensitive detection of biomarkers, which could further assist early diagnosis and intervention for critical illnesses like cancer in the future," said Chinese and Israeli experts who participated in evaluating the research achievement.

"We can't run the test with whole blood yet. Within two years, we plan to improve the procedures and make detection easier by taking a few drops of blood from fingertip," said Wu.

http://www.ecns.cn/2018/02-12/292495.shtml
 
China to build science park in Xi'an

2018-02-12 13:57 Xinhua Editor: Gu Liping

China will build a science park in Xi'an, the capital of northwest China's Shaanxi Province, reported the People's Daily Monday.

Supported by the Chinese Academy of Sciences (CAS) and local governments, the complex will begin to take shape in 2020.

Covering five square kilometers, it will accommodate national scientific research bases, high tech enterprises, an environmental institute, a heavy ion accelerator for medical use and a financial center for scientific research.

http://www.ecns.cn/2018/02-12/292555.shtml
 
Searching for power outlet may soon become thing of past: Chinese, U.S. researchers

2018-02-12 16:53 Xinhua Editor: Gu Liping

Chinese and U.S. researchers have developed a small metallic tab that, when attached to the body, is capable of generating electricity from bending a finger and other simple movements.

Searching for a power outlet may soon become a thing of the past. Instead, devices will receive electricity from the tab, triboelectric nanogenerator.

The researchers' study, published online recently in the journal Nano Energy, describes the tab as being 1.5 centimeters long, by 1 centimeter wide. It delivered a maximum voltage of 124 volts, a maximum current of 10 microamps and a maximum power density of 0.22 milliwatts per square centimeter. That is not enough to quickly charge a smartphone, however, it lit 48 red LED lights simultaneously.

Triboelectric charging occurs when certain materials become electrically charged after coming into contact with a different material. Most everyday static electricity is triboelectric, according to the collaborative research led by University at Buffalo (UB) and Institute of Semiconductors (IoP) at Chinese Academy of Sciences (CAS).

"No one likes being tethered to a power outlet or lugging around a portable charger. The human body is an abundant source of energy. We thought: 'Why not harness it to produce our own power?'" lead author Qiaoqiang Gan, associate professor of electrical engineering in UB's School of Engineering and Applied Sciences, was quoted as saying in a news release.

The tab that the research team is developing addresses both concerns of the difficulty of manufacture and cost-effectiveness.

It consists of two thin layers of gold, with polydimethylsiloxane (PDMS), a silicon-based polymer used in contact lenses, Silly Putty and other products, sandwiched in between.

Key to the device is that one layer of gold is stretched, causing it to crumple upon release and create what looks like a miniature mountain range. When that force is reapplied, for example from a finger bending, the motion leads to friction between the gold layers and PDMS.

"This causes electrons to flow back and forth between the gold layers. The more friction, the greater the amount of power is produced," said another lead author, Yun Xu, professor of IoP at CAS.

The team also plans to use larger pieces of gold, which when stretched and folded together are expected to deliver even more electricity.

Next, researchers are working to develop a portable battery to store energy produced by the tab, according to the news release. They envision the system serving as a power source for various wearable and self-powered electronic devices.

http://www.ecns.cn/2018/02-12/292585.shtml
 
Cancer-fighting nanorobots programmed to seek and destroy tumors
February 12, 2018

Study shows first applications of DNA origami for nanomedicine


In a major advancement in nanomedicine, Arizona State University (ASU) scientists, in collaboration with researchers from the National Center for Nanoscience and Technology (NCNST), of the Chinese Academy of Sciences, have successfully programmed nanorobots to shrink tumors by cutting off their blood supply.

“We have developed the first fully autonomous, DNA robotic system for a very precise drug design and targeted cancer therapy,” said Hao Yan, director of the ASU Biodesign Institute’s Center for Molecular Design and Biomimetics and the Milton Glick Professor in the School of Molecular Sciences.

“Moreover, this technology is a strategy that can be used for many types of cancer, since all solid tumor-feeding blood vessels are essentially the same,” said Yan.

The successful demonstration of the technology, the first-of-its-kind study in mammals utilizing breast cancer, melanoma, ovarian and lung cancer mouse models, was published in the journal Nature Biotechnology (DOI:10.1038/nbt.4071).

Seek and destroy
Yan is an expert in the field of DNA origami, which in the past two decades, has developed atomic-scale manufacturing to build more and more complex structures.

The bricks to build their structures come from DNA, which can self-fold into all sorts of shapes and sizes ---all at a scale one thousand times smaller than the width of a human hair---in the hopes of one day revolutionizing computing, electronics and medicine.

That one day may be coming a bit faster than anticipated.

Nanomedicine is a new branch of medicine that seeks to combine the promise of nanotechnology to open up entirely new avenues for treatments, such as making minuscule, molecule-sized nanoparticles to diagnose and treat difficult diseases, especially cancer.

Until now, the challenge to advancing nanomedicine has been difficult because scientists wanted to design, build and carefully control nanorobots to actively seek and destroy cancerous tumors---while not harming any healthy cells.

The international team of researchers overcame this problem by using a seemingly simple strategy to very selectively seek and starve out a tumor.

This work was initiated about 5 years ago. The NCNST researchers first wanted to specifically cut-off of tumor blood supply by inducing blood coagulation with high therapeutic efficacy and safety profiles in multiple solid tumors using DNA-based nanocarriers. Prof. Hao Yan’s expertise has upgraded the nanomedicine design to be a fully programmable robotic system, able to perform its mission entirely on its own.

“These nanorobots can be programmed to transport molecular payloads and cause on-site tumor blood supply blockages, which can lead to tissue death and shrink the tumor,” said Baoquan Ding, a professor at the NCNST, located in Beijing, China.

Nanorobots to the rescue
To perform their study, the scientists took advantage of a well-known mouse tumor model, where human cancer cells are injected into a mouse to induce aggressive tumor growth.

Once the tumor was growing, the nanorobots were deployed to come to the rescue.

Each nanorobot is made from a flat, rectangular DNA origami sheet, 90 nanometers by 60 nanometers in size. A key blood-clotting enzyme, called thrombin, is attached to the surface.

Thrombin can block tumor blood flow by clotting the blood within the vessels that feed tumor growth, causing a sort of tumor mini-heart attack, and leading to tumor tissue death.

First, an average of four thrombin molecules was attached to a flat DNA scaffold. Next, the flat sheet was folded in on itself like a sheet of paper into a circle to make a hollow tube.

They were injected with an IV into a mouse, then traveled throughout the bloodstream, homing in on the tumors.

The key to programming a nanorobot that only attacks a cancer cell was to include a special payload on its surface, called a DNA aptamer. The DNA aptamer could specifically target a protein, called nucleolin, that is made in high amounts only on the surface of tumor endothelial cells---and not found on the surface of healthy cells.

Once bound to the tumor blood vessel surface, the nanorobot was programmed, like the notorious Trojan horse, to deliver its unsuspecting drug cargo in the very heart of the tumor, exposing an enzyme called thrombin that is key to blood clotting.

The nanorobots worked fast, congregating in large numbers to quickly surround the tumor just hours after injection.

Safe and sound design
First and foremost, the team showed that the nanorobots were safe and effective in shrinking tumors.

“The nanorobot proved to be safe and immunologically inert for use in normal mice and, also in Bama miniature pigs, showing no detectable changes in normal blood coagulation or cell morphology,” said Yuliang Zhao, also a professor at NCNST and lead scientist of the international collaborative team.

Most importantly, there was no evidence of the nanorobots spreading into the brain where it could cause unwanted side effects, such as a stroke.

“The nanorobots are decidedly safe in the normal tissues of mice and large animals,” said Guangjun Nie, another professor at the NCNST and a key member of the collaborative team.

The treatment blocked tumor blood supply and generated tumor tissue damage within 24 hours while having no effect on healthy tissues. After attacking tumors, most of the nanorobots were cleared and degraded from the body after 24 hours.

By two days, there was evidence of advanced thrombosis, and 3 days, thrombi in all tumor vessels were observed.

The key is to trigger thrombin only when it is inside tumor blood vessels. Also, in the melanoma mouse model, 3 out of 8 mice receiving the nanorobot therapy showed complete regression of the tumors. The median survival time more than doubled, extending from 20.5 to 45 days.

They also tried their system in a test of a primary mouse lung cancer model, which mimics the human clinical course of lung cancer patients. They showed shrinkage of tumor tissues after a 2-week treatment.

Science of the very small goes big
For Yan, the important study milestone represents the end of the beginning for nanomedicine.

“The thrombin delivery DNA nanorobot constitutes a major advance in the application of DNA nanotechnology for cancer therapy,” said Yan. “In a melanoma mouse model, the nanorobot not only affected the primary tumor but also prevented the formation of metastasis, showing promising therapeutic potential.”

Yan and his collaborators are now actively pursuing clinical partners to further develop this technology.

“I think we are much closer to real, practical medical applications of the technology,” said Yan. “Combinations of different rationally designed nanorobots carrying various agents may help to accomplish the ultimate goal of cancer research: the eradication of solid tumors and vascularized metastases. Furthermore, the current strategy may be developed as a drug delivery platform for the treatment of other diseases by modification of the geometry of the nanostructures, the targeting groups and the loaded cargoes.”

This work was supported by grants from National Basic Research Plan of China (MoST Program 2016YFA0201601), the National Natural Science Foundation of China (31730032, 21222311, 21573051, 91127021, the National Distinguished Young Scientists program 31325010), Innovation Research Group of National Natural Science Foundation (11621505, 21721002), Beijing Municipal Science & Technology Commission (Z161100000116035, Z161100000116036), CAS Interdisciplinary Innovation Team, K. C. Wong Education Foundation and US National Institutes of Health Director’s Transformative Research Award (R01GM104960-01).


Written by: Joe Caspermeyer

Cancer-fighting nanorobots programmed to seek and destroy tumors | The Biodesign Institute | ASU
 
Chinese research advances highlighted in special issue of Human Gene Therapy
Source: Xinhua| 2018-02-17 02:40:48|Editor: Chengcheng


WASHINGTON, Feb. 15 (Xinhua) -- A special issue of peer-reviewed journal Human Gene Therapy was published on Friday, documenting China's progress, opportunities and challenges in its biomedical research.

"This special issue, released coincident with the New Year in China, illustrates the tremendous scientific progress that has been made at certain leading institutions in China working in cell and gene therapy," says its editor-in-chief Terence R. Flotte, professor of University of Massachusetts Medical School.

The issue has six research articles and 12 special commentaries and review articles covering the world's first gene therapy product for cancer, the rare diseases registry system, and genomic editing and stem-cell therapy advances.

Gendicine, developed by a Shenzhen bio-tech company was approved in 2003 by China Food and Drug Administration (CFDA) as a first-in-class gene therapy product to treat head and neck cancer. It is the first-ever approved gene therapy drug in the world.

In a review article, drug evaluation scientists from CFDA discuss the principles on which clinical review of cellular therapy, including CAR-T products in China are based.

The special issue shows that China is helping to advance gene and cell therapy and genome editing research by creating novel viral and nonviral vectors for gene delivery and innovative applications of CRISPR technology in a broad range of disease areas.

"We hope that these particular focused commentaries can provide a roadmap for gene therapy scientists from other parts of the world to identify important achievements and opportunities for future collaboration," Flotte said.

The journal is owned by Mary Ann Liebert, Inc. publishers, a New York-based media company known for establishing authoritative peer-reviewed journals in many promising areas of science and biomedical research.

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Big data help ease holiday crowds in Shanghai
Source: Xinhua| 2018-02-18 21:39:08|



SHANGHAI, Feb. 18 (Xinhua) -- Shanghai municipal government issued a notice Sunday afternoon on its official Wechat account, advising visitors against flocking to over-crowded tourist attractions.

The Oriental Pearl Radio and TV Tower, Shanghai Museum, and Madame Tussauds wax museum were among a number of tourist sites that had or were about to reach their maximum capacity Sunday afternoon, according to a real-time monitoring system launched by the municipal authorities.

Through the system based on big data analysis, tourists in Shanghai can keep an eye on the size of the crowds in more than 70 tourist attractions in the city and make sensible decisions to avoid the crowds during the holiday.

Shanghai received some 2.54 million visitors during the first four days of the week-long Chinese Lunar New Year holiday, according to Shanghai Municipal Tourism Administration.

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China unveils the world's largest synthetic sapphire crystal


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▲ The world's largest synthetic sapphire crystal was unveiled in China

450公斤级!世界最大人造蓝宝石晶体诞生

2018年02月14日09:11

记者13日从呼和浩特市赛罕区委宣传部获悉,全球最大450公斤级超大尺寸高品质泡生法蓝宝石晶体在内蒙古晶环电子材料有限公司生产车间成功面世。该晶体为晶环电子研发团队自主研发,经过近8个月的设计开发、设备加工、煅烧、长晶等过程,于13日小试成功。经初步检测,该晶体重量445公斤,外形规整,通体透明,无裂纹,无晶界,气泡较少,可应用于LED的4英寸晶棒有效长度达到4550mm以上。

  泡生法是目前国际上主流的晶石生产方法,也是世界各国致力攻关的生产工艺。2017年俄罗斯的350公斤人造蓝宝石被确定为全球最大,这一纪录在一年后即被我国打破。

  晶环电子副总经理、总工程师欧阳鹏根向科技日报记者介绍,泡生法人造蓝宝石的生产技术瓶颈在于自动化设备研发和热产设计,每增加一定体积和质量,核心技术的内容和研发过程就会发生根本性的变化。也就是说,450公斤级和350公斤级人造晶石的核心技术有着本质区别,从这个意义上讲,我国在此领域的技术研发和生产工艺已经超过俄罗斯等世界主要人造晶石生产国。

  据了解,蓝宝石晶体是半导体GaN/ Al2O3发光二极管(LED)、大规模集成电路SOI和SOS及超导纳米结构薄膜等理想的衬底材料,属于国家重点支持和鼓励发展的能源材料及光电子材料。

  “450公斤级的研发成功,将很快改变我国人造晶石领域内200公斤和250公斤级批量生产的现状,将使我国大尺寸蓝宝石材料彻底摆脱进口依赖,大大提高我国在蓝宝石产业的核心竞争力。”晶环电子总经理张俊这样评价。(记者 张景阳)

The world's largest synthetic sapphire crystal was unveiled in China on Monday. The 445kg crystal, which can be used to produce 4-inch sapphire ingots for LEDs, marks a breakthrough for China's research and development in new materials.

The crystal research and development team in Hohhot, Inner Mongolia, succeeded after nearly eight months of design and development, equipment processing, calcination, growth and other processes, on its 13th attempts. After preliminary testing, the weight of the crystal is 445 kg, the shape regular, the whole body transparent, without any cracks, without grain boundaries, presenting less bubbles. It can be used in 4-inch LED with an effective length of more than 4550mm.

Russia's 350 kilos synthetic sapphire was presented as the largest in the world in 2017, a record that was broken by China in less than a year's time.

In this sense, China's R&D and production technology in this field has surpassed the world's major producers of artificial crystal in Russia.

It is understood that the sapphire crystal is an ideal substrate material for semiconductor GaN / Al2O3 light-emitting diode (LED), large-scale integrated circuits SOI and SOS and superconducting nanostructured thin films, and belongs to the energy materials and optoelectronic materials that are supported and encouraged by the state.

The success of the 450kg class R&D will soon change the status of mass production of 200kg and 250kg in China's man-made crystal. This will enable China to completely get rid of its dependence on imported large-size sapphire and greatly enhance China's core competition in the sapphire industry.


http://scitech.people.com.cn/n1/2018/0214/c1057-29823975.html
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Chinese scientists find how bats carry viruses without getting sick

2018-02-23 09:47 Xinhua Editor: Gu Liping

Chinese scientists have identified the secret of bats that harbor highly pathogenic viruses like Ebola, Marburg and SARS coronavirus but do not show clinical signs of disease.

In a paper published on Thursday in the journal Cell Host & Microbe, scientists at the Wuhan Institute of Virology in China find that in bats, an antiviral immune pathway called the STING-interferon pathway is dampened, so bats can maintain just enough defense against illness without triggering a heightened immune reaction.

"We believe there is a balance between bats and the pathogens they carry," said the paper's senior author Zhou Peng.

"This work demonstrated that in order to maintain a balance with viruses, bats may have evolved to dampen certain pathways," Zhou said.

According to researchers, in humans and other mammals, an immune-based over-response to one of these and other pathogenic viruses can trigger severe illness. For example, in humans, an activated STING pathway is linked with severe autoimmune diseases.

"In human history, we have been chasing infectious diseases one after another," said Zhou, "But bats appear to be a 'super-mammal' to these deadly viruses."

By identifying a weakened but not defunct STING pathway in bats, researchers have some new insight into how bats fine-tune antiviral defenses to balance an effective, but not an overt, response against viruses.

They hypothesize that this defense strategy evolved as part of three interconnected features of bat biology: they are flying mammals, have a long lifespan, and host a large viral reservoir.

"Adaptation to flight likely caused positive selection of multiple bat innate immune and DNA damage repair genes," Zhou said.

These adaptations may have shaped certain antiviral pathways including STING, interferon to make them good viral reservoir hosts and achieve a tolerable balance.

Zhou told Xinhua that the study has provided a possibility that people can learn from bats in combating virus although whether this mechanism can be directly used in humans is still unknown.

http://www.ecns.cn/2018/02-23/293220.shtml
 
Chinese scientists find critical gene for heart development

2018-02-28 13:25 Xinhua Editor: Gu Liping

Chinese scientists identified a gene critical for the development of the network of nerves wrapped around the heart and its surrounding vasculature, according to a recently published study.

The discovery can potentially improve the prevention and treatment of diseases like coronary artery disease, a leading global cause of mortality, said the study appeared on Tuesday in the U.S. journal Science Signaling.

Zhang Zhen from Shanghai Children's Medical Center and his colleagues pinpointed the gene "Wdpcp" as an important player in coronary plexus formation in mice.

This gene is known for its role in the formation of cell cilia, or eyelash-like structures that help control locomotion.

The coronary arteries and the nerves surrounding them are essential for providing oxygen and nutrition to the heart muscle.

Their development involves two major steps: the cells from the heart's inner lining form the primitive coronary plexus, which then begins the remodeling process by recruiting cells from outside of the heart, Zhang told Xinhua.

The remodeling stage is essential for smooth muscle cells, the building blocks of artery walls, to surround the vessels in the primitive coronary plexus.

Studying mice with mutated Wdpcp, the researchers found that although the primitive coronary plexus formed properly and rather quickly, the remodeling stage was defective because of impaired migration of cells from the outside of the heart, ultimately stunting the formation of arterial walls.

Similarly, mice with a complete deletion of Wdpcp exhibited the same remodeling defects, and they are notably more severe than those of the Wdpcp mutants.

Zhang's method may serve as a viable animal model for studying the remodeling stages of coronary artery development.

http://www.ecns.cn/2018/02-28/293945.shtml
 
Chinese scientists develop battery operable at extreme low temperature

2018-03-01 09:37 Xinhua Editor: Gu Liping

Chinese researchers have developed a battery with eco-friendly organic compound electrodes that can function at minus 70 degrees Celsius, far colder than the temperature at which lithium-ion batteries lose most of their ability to conduct and store energy.

The findings, published Wednesday in the journal Joule, could aid engineers in developing technology suited to withstand the most frigid regions on Earth or the coldest reaches of outer space.

Most of previous batteries perform at only 50 percent of their optimal level when the temperature hits minus 20 degrees Celsius, and by minus 40 degrees Celsius, lithium-ion batteries only have about 12 percent of their room temperature capacity.

This can be severely limiting when it comes to operating batteries in space, where temperatures can dip to minus 157 degrees Celsius, or in parts of Canada and Russia, where temperatures can be lower than minus 50 degrees Celsius.

Chinese researchers have found a design that can function even where other batteries might fail.

Xia Yongyao, a battery researcher at Fudan University said: "It is well known that both the electrolyte (the chemical medium that carries ions between electrodes) and electrodes (the positively charged cathode and negatively charged anode) have great influence on the battery performance."

When it gets cold, the conventional electrolytes that lithium-ion batteries often use become sluggish conductors and the electrochemical reactions that occur at the interface of the electrolyte and the electrode struggle to continue.

Xia's team experimented with using an ethyl acetate-based electrolyte, which has a low freezing point that enables it to conduct a charge even at extremely low temperatures.

For the electrodes, they used two organic compounds, PTPAn cathode and PNTCDA anode. Unlike the electrodes used in lithium-ion batteries, these organic compounds don't rely on intercalation, the process of continuously integrating ions into their molecular matrix, which slows down as the temperature drops.

"Compared to the transition-metal-containing electrodes materials in conventional lithium-ion batteries, organic materials are abundant, inexpensive, and environmentally friendly," Xia said.

He estimated the price of the electrode materials at about one third of the price of electrodes in a lithium-ion battery.

However, the battery will still require some tweaking before it is ready to leave the lab, because its energy per unit mass is still low compared with commercialized lithium-ion batteries, and the assembly process needs to be further optimized.

http://www.ecns.cn/2018/03-01/294064.shtml
 

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