China Science & Technology Forum

[JSCh]

Chinese scientists discover new material that may allow us to charge our smartphones with our clothes
(People's Daily Online) 15:48, July 24, 2017

Professor Xiong Rengen shows his new findings in the lab. (Photo/Chinanews.com)

Can you imagine the day when you can charge your smartphone simply by stretching in your clothes? A research team from China’s Southeast University has found a new organic-based piezoelectric material that could help this become reality, Chinanews.com reported.

Piezoelectricity refers to electric polarization in a substance, especially certain crystals, caused by mechanical stress. According to Professor Xiong Rengen, who heads the research team, piezoelectric materials have already been applied to various fields, such as spaceflights, submarines, missiles, and medical ultrasounds.

Traditional inorganic piezoelectric materials, such as ceramic, are too stiff to be attached to thin films or electronic components. In addition, thin films and most electronic components get damaged in the extremely high temperatures under which those materials are made.

The new organic piezoelectric materials (Photo/Chinanews.com)

The new organic-based perovskite structured piezoelectric material is far more pliable yet has a piezoelectric response similar to traditional materials. It is also cheaper, lighter, and more environmentally-friendly.

"The molecular piezoelectric materials will further shrink the size of computer chips, making it possible to manufacture flexible heart rate meters and ultrasound machines," Xiong noted, expressing his confidence in the future application of the material.

The research on this new material was published in the Science on July 21, making China a leader in the field of molecular material research.

###
​

An organic-inorganic perovskite ferroelectric with large piezoelectric response
Science ( IF 37.205 ) Pub Date : 2017-07-21 , DOI: 10.1126/science.aai8535
Yu-Meng You, Wei-Qiang Liao, Dewei Zhao, Heng-Yun Ye, Yi Zhang, Qionghua Zhou, Xianghong Niu, Jinlan Wang, Peng-Fei Li, Da-Wei Fu, Zheming Wang, Song Gao, Kunlun Yang, Jun-Ming Liu, Jiangyu Li, Yanfa Yan, Ren-Gen Xiong

Molecular piezoelectrics are highly desirable for their easy and environment-friendly processing, light weight, low processing temperature, and mechanical flexibility. However, although 136 years have passed since the discovery in 1880 of the piezoelectric effect, molecular piezoelectrics with a piezoelectric coefficient d33 comparable with piezoceramics such as barium titanate (BTO; ~190 picocoulombs per newton) have not been found. We show that trimethylchloromethyl ammonium trichloromanganese(II), an organic-inorganic perovskite ferroelectric crystal processed from aqueous solution, has a large d33 of 185 picocoulombs per newton and a high phase-transition temperature of 406 kelvin (K) (16 K above that of BTO). This makes it a competitive candidate for medical, micromechanical, and biomechanical applications.​

 

[JSCh]

Scientists Find the Next Deep-Ultraviolet Nonlinear Optical Material
Jul 25, 2017

Deep-ultraviolet (DUV, wavelength λ<200 nm) nonlinear optical (NLO) materials are crucial for producing solid-state lasers and stimulates great interests because of their wide range of applications in the semiconductor industry.

KBe2BO3F2 (KBBF) is an unique NLO material that can efficiently generate DUV light with a strong layer growth habit and toxicity issue containing beryllium that restricts the applications. Therefore, the exploration and development of the next generation DUV NLO materials is in great importance.

Recently, a research team led by Prof. PAN Shilie at Xinjiang Technical Institute of Physics & Chemistry (XTIPC) of Chinese Academy of Sciences designed and prepared a promising DUV NLO material, NH4B4O6F (ABF), which owns favorable NLO properties comparable to famous KBBF crystal. The study was published in J. Am. Chem. Soc.

In this study, [BO3F] is substituted for [BeO3F] and the NH4+ ionic group is substituted for K cation. ABF was found to perfectly inherit the excellent structure features of KBBF, and exhibit a wide DUV transparency window with a cutoff edge down to 156 nm, a large NLO efficiency (3 × KDP), and suitable birefringence that enable simple frequency doubling below 200 nm (as short as 158 nm).

Compared with KBBF, this material has a compact structure with enhanced interlayer binding forces. Researchers obtained up to the centimeter-level bulk crystals. In addition, ABF can be made with an environment-friendly synthesis process without using highly toxic beryllium oxide powders. These optimizations reduce the health risk during crystal growth and are beneficial to industrial applications – insurmountable problems facing KBBF.

Besides, researchers found that ABF exhibits a NLO efficiency about 2.5 times that of KBBF. Since the conversion efficiency is proportional to the square of deff, ABF will possess much better performance than KBBF in DUV frequency conversion process. All those properties make ABF an ideal candidate of next generation DUV NLO material.

This work was financially supported by National Natural Science Foundation of China, National Key Research Project, and Xinjiang Key Research and Development Program.



Scientists Find the Next Deep-Ultraviolet Nonlinear Optical Material---Chinese Academy of Sciences

 

[Bussard Ramjet]

Scientists Find the Next Deep-Ultraviolet Nonlinear Optical Material
Jul 25, 2017

Deep-ultraviolet (DUV, wavelength λ<200 nm) nonlinear optical (NLO) materials are crucial for producing solid-state lasers and stimulates great interests because of their wide range of applications in the semiconductor industry.

KBe2BO3F2 (KBBF) is an unique NLO material that can efficiently generate DUV light with a strong layer growth habit and toxicity issue containing beryllium that restricts the applications. Therefore, the exploration and development of the next generation DUV NLO materials is in great importance.

Recently, a research team led by Prof. PAN Shilie at Xinjiang Technical Institute of Physics & Chemistry (XTIPC) of Chinese Academy of Sciences designed and prepared a promising DUV NLO material, NH4B4O6F (ABF), which owns favorable NLO properties comparable to famous KBBF crystal. The study was published in J. Am. Chem. Soc.

In this study, [BO3F] is substituted for [BeO3F] and the NH4+ ionic group is substituted for K cation. ABF was found to perfectly inherit the excellent structure features of KBBF, and exhibit a wide DUV transparency window with a cutoff edge down to 156 nm, a large NLO efficiency (3 × KDP), and suitable birefringence that enable simple frequency doubling below 200 nm (as short as 158 nm).

Compared with KBBF, this material has a compact structure with enhanced interlayer binding forces. Researchers obtained up to the centimeter-level bulk crystals. In addition, ABF can be made with an environment-friendly synthesis process without using highly toxic beryllium oxide powders. These optimizations reduce the health risk during crystal growth and are beneficial to industrial applications – insurmountable problems facing KBBF.

Besides, researchers found that ABF exhibits a NLO efficiency about 2.5 times that of KBBF. Since the conversion efficiency is proportional to the square of deff, ABF will possess much better performance than KBBF in DUV frequency conversion process. All those properties make ABF an ideal candidate of next generation DUV NLO material.

This work was financially supported by National Natural Science Foundation of China, National Key Research Project, and Xinjiang Key Research and Development Program.



Scientists Find the Next Deep-Ultraviolet Nonlinear Optical Material---Chinese Academy of Sciences

This should not have been published. This should have been classified.

Chinese scientists are paid generous sums for publishing, and their careers depend on publishing. This needs to change.

 

[JSCh]

This should not have been published. This should have been classified.

Chinese scientists are paid generous sums for publishing, and their careers depend on publishing. This needs to change.

I do not think the publishing will show how the crystal is made.

The crystal made by China would probably be barred from export.

Like KBBF that is being discuss here -> https://defence.pk/pdf/threads/us-f...-laser-crystal-breaks-chinese-embargo.422020/

 

[Bussard Ramjet]

I do not think the publishing will show how the crystal is made.

The crystal made by China would probably be barred from export.

Like KBBF that is being discuss here -> https://defence.pk/pdf/threads/us-f...-laser-crystal-breaks-chinese-embargo.422020/

Sometimes even the fact that someone has made something is a big give away.

Many times the most painful process is to do a thousand different experiments and take thousand approaches, without any result. But your work becomes very easy, if you know for a FACT that a particular kind of compound, with particular properties achieved something.

Here, not only did you release a LOT of vital stuff, but one author is American! America can reciprocate that whenever they want.

 

[Han Patriot]

Sometimes even the fact that someone has made something is a big give away.

Many times the most painful process is to do a thousand different experiments and take thousand approaches, without any result. But your work becomes very easy, if you know for a FACT that a particular kind of compound, with particular properties achieved something.

Here, not only did you release a LOT of vital stuff, but one author is American! America can reciprocate that whenever they want.

US have been lagging behind China in high powered laser, this could be an even bigger lead vs US. I agree this technology should be under embargo. Having said this, research paper doesn't reveal much about a particular technology, but it does trigger US into frenzy mode to catch up.

 

[Keel]

Chinese scientists discover new material that may allow us to charge our smartphones with our clothes
(People's Daily Online) 15:48, July 24, 2017

Professor Xiong Rengen shows his new findings in the lab. (Photo/Chinanews.com)

Can you imagine the day when you can charge your smartphone simply by stretching in your clothes? A research team from China’s Southeast University has found a new organic-based piezoelectric material that could help this become reality, Chinanews.com reported.

Piezoelectricity refers to electric polarization in a substance, especially certain crystals, caused by mechanical stress. According to Professor Xiong Rengen, who heads the research team, piezoelectric materials have already been applied to various fields, such as spaceflights, submarines, missiles, and medical ultrasounds.

Traditional inorganic piezoelectric materials, such as ceramic, are too stiff to be attached to thin films or electronic components. In addition, thin films and most electronic components get damaged in the extremely high temperatures under which those materials are made.

The new organic piezoelectric materials (Photo/Chinanews.com)

The new organic-based perovskite structured piezoelectric material is far more pliable yet has a piezoelectric response similar to traditional materials. It is also cheaper, lighter, and more environmentally-friendly.

"The molecular piezoelectric materials will further shrink the size of computer chips, making it possible to manufacture flexible heart rate meters and ultrasound machines," Xiong noted, expressing his confidence in the future application of the material.

The research on this new material was published in the Science on July 21, making China a leader in the field of molecular material research.

###
​

An organic-inorganic perovskite ferroelectric with large piezoelectric response
Science ( IF 37.205 ) Pub Date : 2017-07-21 , DOI: 10.1126/science.aai8535
Yu-Meng You, Wei-Qiang Liao, Dewei Zhao, Heng-Yun Ye, Yi Zhang, Qionghua Zhou, Xianghong Niu, Jinlan Wang, Peng-Fei Li, Da-Wei Fu, Zheming Wang, Song Gao, Kunlun Yang, Jun-Ming Liu, Jiangyu Li, Yanfa Yan, Ren-Gen Xiong

Molecular piezoelectrics are highly desirable for their easy and environment-friendly processing, light weight, low processing temperature, and mechanical flexibility. However, although 136 years have passed since the discovery in 1880 of the piezoelectric effect, molecular piezoelectrics with a piezoelectric coefficient d33 comparable with piezoceramics such as barium titanate (BTO; ~190 picocoulombs per newton) have not been found. We show that trimethylchloromethyl ammonium trichloromanganese(II), an organic-inorganic perovskite ferroelectric crystal processed from aqueous solution, has a large d33 of 185 picocoulombs per newton and a high phase-transition temperature of 406 kelvin (K) (16 K above that of BTO). This makes it a competitive candidate for medical, micromechanical, and biomechanical applications.​

Scientists Find the Next Deep-Ultraviolet Nonlinear Optical Material
Jul 25, 2017

Deep-ultraviolet (DUV, wavelength λ<200 nm) nonlinear optical (NLO) materials are crucial for producing solid-state lasers and stimulates great interests because of their wide range of applications in the semiconductor industry.

KBe2BO3F2 (KBBF) is an unique NLO material that can efficiently generate DUV light with a strong layer growth habit and toxicity issue containing beryllium that restricts the applications. Therefore, the exploration and development of the next generation DUV NLO materials is in great importance.

Recently, a research team led by Prof. PAN Shilie at Xinjiang Technical Institute of Physics & Chemistry (XTIPC) of Chinese Academy of Sciences designed and prepared a promising DUV NLO material, NH4B4O6F (ABF), which owns favorable NLO properties comparable to famous KBBF crystal. The study was published in J. Am. Chem. Soc.

In this study, [BO3F] is substituted for [BeO3F] and the NH4+ ionic group is substituted for K cation. ABF was found to perfectly inherit the excellent structure features of KBBF, and exhibit a wide DUV transparency window with a cutoff edge down to 156 nm, a large NLO efficiency (3 × KDP), and suitable birefringence that enable simple frequency doubling below 200 nm (as short as 158 nm).

Compared with KBBF, this material has a compact structure with enhanced interlayer binding forces. Researchers obtained up to the centimeter-level bulk crystals. In addition, ABF can be made with an environment-friendly synthesis process without using highly toxic beryllium oxide powders. These optimizations reduce the health risk during crystal growth and are beneficial to industrial applications – insurmountable problems facing KBBF.

Besides, researchers found that ABF exhibits a NLO efficiency about 2.5 times that of KBBF. Since the conversion efficiency is proportional to the square of deff, ABF will possess much better performance than KBBF in DUV frequency conversion process. All those properties make ABF an ideal candidate of next generation DUV NLO material.

This work was financially supported by National Natural Science Foundation of China, National Key Research Project, and Xinjiang Key Research and Development Program.



Scientists Find the Next Deep-Ultraviolet Nonlinear Optical Material---Chinese Academy of Sciences

Keep going and well done!
Give the scientists handsome rewards if thorough reviews and checking justify the awards.
Nobody is more authoritative than the review board, the peers acting in good faith!
Keep producing more great scientific outputs, China!

 

[Bussard Ramjet]

US have been lagging behind China in high powered laser, this could be an even bigger lead vs US. I agree this technology should be under embargo. Having said this, research paper doesn't reveal much about a particular technology, but it does trigger US into frenzy mode to catch up.

What makes you think US has been lagging?

 

[Han Patriot]

What makes you think US has been lagging?

http://english.cas.cn/bcas/2013_4/201411/P020141121530076315486.pdf

This was in 2013. Please proof me wrong? KBBF crystal were embargoed by China until US developed them a few years ago.

 

[Bussard Ramjet]

http://english.cas.cn/bcas/2013_4/201411/P020141121530076315486.pdf

This was in 2013. Please proof me wrong? KBBF crystal were embargoed by China until US developed them a few years ago.

One crystal has got nothing to do with the overall state of laser research.

In fact the bottlenecks in laser development is entirely different stuff. It is power management, laser formation etc.

This crystal just transforms one laser into another particular kind of laser, that is used in niche applications.

Otherwise why would US not have developed it earlier? The US did develop it once they were embargoed, within 3-4 years, and with only 10 million or so dollars of investment.

 

[Han Patriot]

One crystal has got nothing to do with the overall state of laser research.

In fact the bottlenecks in laser development is entirely different stuff. It is power management, laser formation etc.

This crystal just transforms one laser into another particular kind of laser, that is used in niche applications.

Otherwise why would US not have developed it earlier? The US did develop it once they were embargoed, within 3-4 years, and with only 10 million or so dollars of investment.

The crystals are the core of the laser technology, power management and light source are all auxiliary components bro. The fact that they do not possess KBBF crystals until a few years ago showed the state of their technology, notice how they felt constrained over Chinese embargo if you read the APC article properly. It is no coincidence China introduce a few laser weapons earlier than the Americans.

 

[JSCh]

Public Release: 25-Jul-2017
Color-shifting electronic skin could have wearable tech and prosthetic uses
IOP Publishing

The ability of some animals, including chameleons, octopus, and squid, to change their skin colour for camouflage, temperature control, or communication is well known.

While science has been able to replicate these abilities with artificial skin, the colour changes are often only visible to the naked eye when the material is put under huge mechanical strain.

Now, however, researchers in China have developed a new type of user-interactive electronic skin, with a colour change perceptible to the human eye, and achieved with a much-reduced level of strain. Their results could have applications in robotics, prosthetics and wearable technology.

Published today in the journal 2D Materials, the study from Tsinghua University in Beijing, employed flexible electronics made from graphene, in the form of a highly-sensitive resistive strain sensor, combined with a stretchable organic electrochromic device.

Lead author Dr Tingting Yang, from Tsinghua University, said: "We explored the substrate (underlying) effect on the electromechanical behaviour of graphene. To obtain good performance with a simple process and reduced cost, we designed a modulus-gradient structure to use graphene as both the highly sensitive strain-sensing element and the insensitive stretchable electrode of the ECD layer.

"We found subtle strain - between zero and 10 per cent - was enough to cause an obvious colour change, and the RGB value of the colour quantified the magnitude of the applied strain."

Senior author Professor Hongwei Zhu said: "Graphene, with its high transparency, rapid carrier transport, flexibility and large specific surface area, shows application potential for flexible electronics, including stretchable electrodes, supercapacitor, sensors, and optical devices.

"However, our results also show that the mechanical property of the substrate was strongly relevant to the performance of the strain sensing materials. This is something that has previously been somewhat overlooked, but that we believe should be closely considered in future studies of the electromechanical behaviour of certain functional materials."

Dr Yang said: "It's important to note that the capability we found for interactive colour changes with such a small strain range has been rarely reported before. This user-interactive e-skin should be promising for applications in wearable devices, robots and prosthetics in the future."


Color-shifting electronic skin could have wearable tech and prosthetic uses | EurekAlert! Science News

 

[JSCh]

China contributes one fifth of the world's computer science papers
Source: Xinhua| 2017-07-25 20:31:21|Editor: Mengjie



BEIJING, July 25 (Xinhua) -- Papers written by Chinese academics account for 23 percent of the world's total, according to figures released at a Chinese computer summit Tuesday.

Over 100 academics and entrepreneurs gathered to exchange views on undergraduate computer science education at the Future Computer Education Summit 2017, held by China Computer Federation (CCF).

Due to the country's investment and individuals' passions for computer research and development, the number of papers written by Chinese academics has increased greatly from just 2 percent on the world total in 1997, according to the CCF.

"Despite the increase, China's undergraduate computer science education still lags behind top-ranking international colleges," said Gao Wen, chairman of the CCF.

Zhou Aoying, vice president of East China Normal University suggested at the summit that colleges and universities should increase the numbers of computer science teachers, and cooperate with companies to develop more talent.

 

[JSCh]

Chinese scientists create biggest virtual universe with world’s fastest computer, beating European record
The achievement, which dwarfed Switzerland’s record set only last month, will help researchers in their efforts to unlock the secrets of the cosmos

• PUBLISHED : Thursday, 27 July, 2017, 12:45pm
• UPDATED : Thursday, 27 July, 2017, 1:35pm
• Stephen Chen

The Sunway TaihuLight supercomputer, based in Wuxi, is the world’s fastest supercomputer. Photo: Xinhua

Chinese scientists have created the largest virtual universe on Sunway TaihuLight, the world’s fastest computer, according to a lead researcher on the project.

Experts said that China was learning to take full advantage of its raw calculation power, which had outpaced other nations in recent years, and recreating the universe was just the first step.

Researchers hope that within three years the country will be leading the way in making new findings about the birth of the cosmos.

The development of the next generation of high-performance computers will allow researchers to work in tandem with other advanced technological facilities, such as the world’s largest radio telescope, to unlock the secrets of the universe.

By simulating the creation of the universe on Sunway – or its more advanced successors – researchers will be able to single out distant areas of space for the telescope to investigate.

Gao Liang, chair scientist of the computational cosmology group in the National Astronomical Observatories, Chinese Academy of Sciences in Beijing, said they simulated the birth and early expansion of the universe using 10 trillion digital particles.

This project’s scale was five times greater than that of the previous record, which was achieved last month by astrophysicists at the University of Zurich in Switzerland, he added.

The work was carried out at the National Supercomputer Centre in Wuxi, Jiangwu two months ago.

“There were lots of calculations... It must be exhausted,” Gao said.

He explained that Sunway had used a total of 10 million CPU cores, running multiple instructions on each core to increase the speed of calculation.

The simulation was disclosed to the public for the first time on Wednesday in an article by Wang Qiao, another scientist taking part in the project, for S cience and Technology Daily, the official newspaper of the Ministry of Science and Technology of China.

The Sunway was stretched to its limit by the task, but it remained heathy, according to Gao.

“This is just a warm-up exercise. We still have a long way ahead to get what we want,” he said.

In astronomy, researchers simulate the universe by breaking down its mass into particles. These particles interact with one another through physical forces such as gravity. The more particles involved, the more precisely the scientists can replay and forecast the universe’s evolution. This process can shed light on many issues such as the nature and spread of dark energy.

The calculation, also known as N-body simulation, intensified with the increase of particles. It was only possible to simulate over 1,000 particles with the best computers in 1970s. In recent years scientists reached the trillion-particle level on some of the world’s most powerful machines such as the Titan in the US, the K computer in Japan and Tianhe-2 in Guangzhou.

But the Sunway left the competitors trailing in its wake with its unprecedented performance.

Built entirely from China’s home-made chips with exceptionally low energy consumption, the Sunway has topped the world’s supercomputer chart since June last year.

Its linkpack benchmark rate - the maximum speed at which it can operate – has reached 93 petaflops (a thousand trillion floating point operations per second). This was nearly three times faster than its closest competitor, Tianhe-2, which was also built by China.

But Chinese supercomputers are known for a major weakness and have rarely operated at full capacity. Running full throttle would impose a strain on their hardware. Sophisticated, tailor-made software is also needed to coordinate the large number of processing units and cores within the machine.

Lin Weipeng, a professor with the Institute of Astronomy and Space Science at Sun Yat-sen University in Guangzhou, said the Sunway simulation was a milestone event in China’s rise as a research superpower.

“They did not just find a rein to tame the beast but kicked it up to a neck-breaking spring. Their work will allow China to take full advantage of its hardware superiority and stay on top in the race,” said Lin, who was informed but not involved in the project.

Lin said the unique physical structure of Sunway and its home-grown chip meant Gao’s team had to write most of the software from the bottom up. It was a labour-intensive task complicated by the use of many sophisticated algorithms.

One error in code line could have crashed the whole machine, he said.

Due to the shortage of powerful software, Chinese supercomputers often have to divide their chips to run medium or even small-scale tasks for different clients. “This is not what a supercomputer is built for,” Lin said.

“But it is about to change,” he added.

Gao said Sunway remained stable at its peak performance. The chips were hot but not overheated, and their cores engaged with their assigned tasks efficiently.

“But we have a regret,” Gao explained – the simulation ran just over an hour, as the centre had other clients waiting in line to use the machine.

“We just got to the point of tens of millions years after the Big Bang. It was still a very young stage for the universe. Most galaxies were not even born,” he said.

The current age of the universe is about 1.3 billion years. To simulate how it got to where it is, scientists would need a longer run-time on Sunway, according to Gao.

“Or its successor, which is better,” he said.

China has been building its next-generation high performance computer which will be at least 10 times faster than Sunway. When the machine is finished around 2019, astronomers in China will have more calculation resources than their peers in most other countries to uncover the secrets of the universe, according to Gao.

The supercomputers will work alongside China’s other large scientific facilities, including Fast, the world’s single largest radio telescope which is 500 metres in diameter, in Guizhou.

The telescope, whose name stands for the “Five hundred metre Aperture Spherical Telescope”, could obtain detailed information from the distant universe, but first it would need to know where to look.

By simulating the evolution of the universe on a computer, researchers can single out promising regions that may offer interesting findings and feed the coordinates to the telescope.

“After 2020, the weight of new discoveries about the universe may shift to China,” Gao said.


Chinese scientists create biggest virtual universe with world’s fastest computer, beating European record | South China Morning Post

 

[JSCh]

Rosemary Clandos
July 27, 2017 11:00 AM
Gut Bacterium Jams Colorectal Cancer-Death Button
Fusobacterium nucleatum promotes resistance to chemotherapy in colon cancer patients by turning off the push button for cancer cell suicide, a new study finds.

A type of bacterium is associated with the recurrence of colorectal cancer and poor outcomes, researchers at Michigan Medicine and in China showed. Specifically, they found that Fusobacterium nucleatum in the gut can stop chemotherapy from causing a type of cancer cell death called apoptosis.

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Colorectal cancer is the third most common cancer and the second leading cause of cancer-related death in the U.S., according to the American Cancer Society. The two most widely used drugs to treat colorectal cancer act to either inhibit enzyme activity of cancer cells or arrest tumor cell growth. But the bacterium can make them ineffective.

“We treat patients with chemotherapy so that it will ultimately induce tumor cell apoptosis. But some cancer cells have a way to avoid apoptosis that is induced by chemotherapy,” says Weiping Zou, M.D., Ph.D., professor of surgery at Michigan Medicine. “Those cells escape from the apoptosis process by activating a cell-survival mechanism called autophagy. That mechanism protects cancer cells from destructing.

“Once autophagy is active, the cancer becomes resistant to chemotherapy. Then Fusobacterium nucleatum keeps autophagy turned on. That’s how the tumor cells may be able to avoid the induced apoptosis,” says Zou.

Typically, autophagy can be turned on or off. But the bacterium prevents the expression of two microRNAs that, in turn, keeps the autophagy turned in the “on” position, he adds.

The collaborative study is published in Cell. The research was led by two teams, Zou at Michigan Medicine, and Jing-Yuan Fang, M.D., Ph.D., in Shanghai. Fang is a professor in Renji Hospital at the Shanghai Jiao Tong University School of Medicine.

"We think that if we deal with this bacterium, we may be able to delay and prevent chemoresistance in colorectal cancer."

Weiping Zou, M.D., Ph.D.​

Building on past work
The idea to check the role of the bacterium associated with innate immune signaling in chemotherapy resistance was linked to an earlier study from this research team, published in Cell in 2016. In the previous paper, they studied adaptive immunity, specifically the impact of T-cells on chemoresistance, finding that it was reversely associated with resistance of cisplatin, the drug used for ovarian cancer. This means if patients have a strong T-cell immunity, their cancer cells are more sensitive to chemotherapy.

SEE ALSO: Free C3d Regulates Immune Checkpoint Blockade and Enhances Anti-Tumor Immunity

In the new Cell study, they researched whether bacterium-mediated innate immune signaling regulates chemotherapy resistance in colon cancer.

The innate immune system refers to the front-line defenders — the cells and molecular mechanisms that attack pathogens. The adaptive immune system is the body’s response to specific antigens, such as foreign substances from bacteria or tumor-associated antigens from tumor cells.

Adaptive immunity is mediated by T-cell signaling. Innate immunity is mediated by innate signaling including proteins called Toll-like receptors.

“We knew that the body uses both systems, adaptive and innate, to fight cancer and infectious pathogens. That gave us the inspiration to look further at bacterium associated with innate immune signaling.

“The results of the research were a surprise. We did not expect bacterium to contribute to chemoresistance,” says Zou.

There are other factors that are unknown about F. nucleatum. For example, what would happen if the bacterium were reduced or blocked? Might other prevalent bacterium create a similar problem with chemoresistance?

“Right now, we don’t have a specific approach to selectively treat or control Fusobacterium nucleatum. Also, we don’t know if an abundance of this bacterium is found in any other types of cancer chemoresistance,” says Zou. “Still, based on our studies, we think that if we deal with this bacterium, we may be able to delay and prevent chemoresistance in colorectal cancer.”


Gut Bacterium Jams Colorectal Cancer-Death Button | University of Michigan

TaChung Yu, Fangfang Guo, Yanan Yu, Tiantian Sun, Dan Ma, Jixuan Han, Yun Qian, Ilona Kryczek, Danfeng Sun, Nisha Nagarsheth, Yingxuan Chen, Haoyan Chen, Jie Hong, Weiping Zou, Jing-Yuan Fang. Fusobacterium nucleatum Promotes Chemoresistance to Colorectal Cancer by Modulating Autophagy. Cell, July 2017 DOI: 10.1016/j.cell.2017.07.008