International - Paper Test Could Make Drug Treatment Safer

Researchers have developed a finger-prick blood sample device to detect serious liver damage.

Researchers looking to make tuberculosis (TB) and HIV treatment safer have developed a paper-based test for drug-induced liver damage.

Standard treatments for TB such as rifampicin and pyrazinamide can cause liver damage, particularly in people co-infected with hepatitis B or C, which are common in Asia.

Similarly, patients can experience liver damage if they are treated for HIV with commonly used nevirapine-based drugs.

Yet clinicians in developing countries rarely have easy access to tests for drug-induced liver injury, said Nira Pollock, assistant professor of medicine at Harvard Medical School in the United States.

US doctors routinely check for high levels of chemical markers in blood that show if patients are developing serious liver damage, and then adjust their medication accordingly.

Now, researchers have developed and tested a stamp-sized paper device with channels and wells that mix, split, and filter a finger-prick blood sample to detect these chemical markers.

The trial used existing blood samples to compare the device to standard tests. It showed an overall accuracy of more than 90 percent compared with the gold standard of 100 percent.

It takes just 15 minutes to get the color changes that indicate normal, moderate, or high levels of liver markers. The test also includes a control that confirms the test was accurate.

The estimated cost of each test is just ten US cents, compared with upfront costs of thousands of dollars for existing point-of-care mini laboratory devices.

Jason Rolland, senior director of research from Diagnostics For All, which developed the technology, said the test is cheap, easy to use, and portable, with no need for electricity or instrumentation.

“It is designed to be used in a rural clinic to support our mission in the developing world,” he added.

Usually liver function testing for patients in rural areas requires samples to be sent to large hospitals, and they can get lost en route, said Rolland. He added that drug-induced liver damage rates are between ten and 25 percent in the developing world, compared to around two percent of patients being treated for TB in the developed world.

Pollock coordinated the trial and is liaising with the National Hospital for Tropical Diseases in Vietnam to conduct field trials of the device in patients suffering from HIV.

If the test works as well in patients, the researchers are hoping to have a commercial product in 2014.

Currently, Diagnostics for All is able to manufacture 500 to 1,000 tests per day.

Commenting on the research, Alison Grant, assistant professor of medicine at the London School of Hygiene and Tropical Medicine, said the technology “could be very useful for patients at high risk or thought to have liver damage.”

But she cautioned that not all patients benefit from routine liver function testing, and WHO guidelines recommend it only for patients at highest risk.

And the cost could be higher than stated.

“Experience of other point-of-care tests suggests that in addition to initial training, staff need refresher training periodically to be sure they are using the test correctly, and this support needs to be taken into account when estimating the true cost of the test,” Grant added.

Rachel Mundy

The article can be found at: Pollock NR et al. (2012) A Paper-Based Multiplexed Transaminase Test for Low-Cost, Point-of-Care Liver Function Testing.

Source: Science and Development Network

Science and Development Network |Tech & Pharma

China - Most paper cups in China not safe to use

Most paper cups available on the Chinese market would not meet the new national standard, which comes into effect on June 1, according to industry insiders.

The country's first regulation on disposable cups will focus on raw materials, additives and printed patterns, and is aimed at boosting consumer safety.

However, as the new rule does not include details on any penalties for offenders, experts predicted on Monday that the standard is unlikely to have a major impact in the short-term.

"Most cups, not only those served at small, roadside restaurants, but also those provided by big-name catering companies, will be substandard once the national standard comes into force," said Dong Jinshi, executive vice-president of the International Food Packaging Institute in Beijing.

The regulation will require a great number of products to be taken off the shelves, he said, but without enforcement people will continue to be "left with no choice but to use cups that may be hazardous to their health".

Among the biggest changes in the standard, issued by the General Administration of Quality Supervision, Inspection and Quarantine and the Standardization Administration, is the restrictions on printing.

Starting next month, colored patterns on paper cups cannot be within 15 millimeters from the lip or 10 millimeters from the bottom.

This, Dong said, is to prevent the oil or ink used to make the pattern from contaminating the inside of another cup when they are stacked.

"Companies tend to brand disposable cups with gaudy, colorful prints," Dong said. "However, it's very easy for the customers to ingest the ink while drinking if the pattern is too close to the top."

He said most pattern prints contain benzene, which ingested over time can cause cancer and leukemia.

Change ahead

Bao Xinchun, sales manager for Beijing Heyi Packing Equipment, which supplies big-name brands like Subway, Holiland and Quanjude, said catering companies have already started consulting him over the new regulations.

However, he expects to see few of them make drastic changes to their cups in the near future.

"Most patterns printed on paper cups for the catering industry would fail to meet the new standard," he said.

"But companies will be concerned that it might influence their business if they all of a sudden change the patterns that they have been using for years, especially for the catering companies, who need to attract customers.

"Unless authorities come up with a penalty for those who violate the rules, I don't think it's possible or practical for firms to have their patterns wiped off or altered."

In addition to the limit on patterns, the standard also imposes requirements on raw materials and bans disposable cups from being made from recycled materials.

Cups with a soft texture and tendency to leak will also be disqualified, while paper cups are required to be dustproof and mold-proof.

In the meantime, food packaging expert Dong said, consumers should avoid products with elaborate patterns.

"The more patterns on the cup the more possible it is for people to take the oil in and harm their health," he said. "It is highly suggested people purchase plain cups or those with little pattern on them."

China Daily/Asia News Network

Switzerland - A new paper made of graphene and protein fibrils

The final hybrid nanocomposite paper made of protein fibrils and graphene after vacuum filtration drying. The schematic route used by the researchers to combine graphene and protein fibrils into the new hybrid nanocomposite paper. (Reproduced from Li et al. Nature Nanotechnology 2012)

Researchers led by Raffaele Mezzenga, a professor in Food and Soft Materials Science, have created a new nanocomposite made of graphene and protein fibrils: a special paper, which combines the best features of both components.

The circular sheets that Raffaele Mezzenga gently lifts from a petri dish are shiny and black. Looking at this tiny piece of paper, one could hardly imagine that it consists of a novel nanocomposite material, with some unprecedented and unique properties, developed in the laboratory of the ETH professor.

This new "paper" is made of alternating layers of protein and graphene. The two components can be mixed in varying compositions, brought into solution, and dried into thin sheets through a vacuum filter – "similarly as one usually does in the manufacture of normal paper from cellulose" says Mezzenga. "This combination of different materials with uncommon properties produces a novel nanocomposite with some major benefits," says the ETH professor. For example, the material is entirely biodegradable.

"Graphene paper" has shape memory features

Graphene is mechanically strong and electrically conductive, as well as, highly water repellent by nature. On the other hand, the protein fibrils are biologically active and can bind water. This allows the new material to absorb water and to change shape under varying humidity conditions. Furthermore, the "graphene paper" has shape memory features such that it can deform when adsorbing water, and recover the original shape upon drying. This could be used, for example, either in water sensors or humidity actuators.

But "the most interesting feature is that we can use this material as abiosensor to precisely measure the activity of enzymes," says Mezzenga. Enzymes can digest and break down the protein fibrils. This changes the resistance of the composite, which is a measurable quantity once the graphene paper is incorporated into an electrical circuit. "This feature is, for me, the nicest part of the story. Seen from this angle, we could claim to have discovered a new general method to measure enzymatic activity”, says the ETH professor.

The material can also be designed to meet other needs. For example, the higher the proportion of graphene, the better it conducts electricity. On the other hand, the more fibrils are present, the more water can be absorbed by this material, with enhanced deformations in response to humidity changes.

Interestingly, this new material can be made with relatively simple means.

The protein, in this case, beta-lactoglobulin, a milk protein, is first denatured by high temperatures in an acidic solution.

The end-products of this denaturation process are protein fibrils suspended in water; these fibrils then act as stabilizers for the hydrophobic graphene sheets and allow them to be finely dispersed in water and processed into nanocomposites by a simple filtration technology.

The concept can be extended

In view of the widespread tendency of proteins to form fibrils, under specific conditions, this concept can be extended, in principle to other food proteins, such as those found in eggs, blood serum and soy. The beta-lactoglobulin fibrils used in the work lead by Mezzenga are digested specifically by pepsin, an enzyme present in the stomach to enable the digestion of several food components.

However, varying the protein types could provide a new method of targeting a much larger class of enzymes.

Inspired by their past research on amyloid fibrils and by the rise of graphene, the ETH researchers have combined these two building blocks to generate a new class of versatile and functional materials.

“Nowadays, graphene paperis no longer a novelty”, says Mezzenga, “it is the combination with amyloid fibrils which is central to this new class of hybrid materials”.

More information: Li C, Adamcik J & Mezzenga R. Biodegradable nanocomposites of amyloid fibrils and graphene with shape-memory and enzyme sensing properties. Nature Nanotechnology 2012.doi:10.1038/nnano.2012.62

Provided by ETH Zurich (news : web)

http://phys.org

China - China To Reduce Dioxin Pollution From Pulp And Paper Industry

The World Bank has awarded China a US$15 million grant from the Global Environment Facility to support reduction of dioxins from its pulp and paper industry.

AsianScientist (Apr. 2, 2012) – The World Bank has awarded the People’s Republic of China a US$15 million grant from the Global Environment Facility (GEF) to support reduction of dioxins from its pulp and paper industry.

The Dioxins Reduction from the Pulp and Paper Industry Project will assist China to implement its national strategy in this sector.

Persistent organic pollutants (POPs) are a group of chemical substances including pesticides, industrial chemicals, and unintentional by-products of industrial processes that persist in the environment. Dioxins are one type of the 21 POPs listed in the Stockholm Convention on POPs.

These POPs can lead to serious health effects, including certain cancers, birth defects, dysfunctional immune and reproductive systems, greater susceptibility to disease and even diminished intelligence.

Among others, pulp and paper production forms and releases dioxins unintentionally if elemental chlorine bleaching technologies are used.

As a signatory to the Stockholm Convention, China has proposed to adopt a series of measures to control and reduce dioxins release from its pulp and paper industry before 2015.

The World Bank sponsored project will focus on demonstrating best available techniques (BAT) and best environmental practices (BEP) in four existing non-wood mills which typify the most commonly used non-wood fiber material in China: straw, reed, bamboo, and bagasse.

Support will also be provided to strengthen the government’s capacity in monitoring and enforcement of a national dioxin standard issued recently.

Based on the results of the demonstration projects, China will develop a long-term national action plan to scale up efforts and further control the formation and release of UPOPs from both the wood and non-wood pulp sectors.

“China has been very proactive in identifying and tackling its POPs issues since its signing of the Stockholm Convention in 2004,” said World Bank’s Senior Environmental Specialist Jiang Ru and task manager of the project.

“As the first project working on unintentionally produced POPs from its industrial sectors, this project will showcase how industrial sectors can address POPs without compromising their competitiveness,” Jiang added.

Established in 1991, the GEF is today the largest funder of projects to improve the global environment. It provides grants to developing countries and countries in transition for projects related to biodiversity, climate change, international waters, land degradation, the ozone layer, and POPs.

——

Source: The World Bank.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.