Cannabinoid compounds may inhibit growth of colon cancer cells

Date: February 6, 2019 Source: Penn State Summary: Medical marijuana has gained attention in recent years for its potential to relieve pain and short-term anxiety and depression. Now, researchers say some cannabinoid compounds may actually inhibit the growth of colon cancer cells in the lab.

Medical marijuana has gained attention in recent years for its potential to relieve pain and short-term anxiety and depression. Now, Penn State College of Medicine researchers say some cannabinoid compounds may actually inhibit the growth of colon cancer cells in the lab.

The researchers tested the effects of synthetic cannabinoid compounds on colon cancer cells in an experiment in test tubes. While the compounds most commonly associated with cannabis -- THC and CBD -- showed little to no effect, 10 other compounds were effective at inhibiting cancer cell growth.

Kent Vrana, chair of the Department of Pharmacology at Penn State College of Medicine, said the study -- recently published in Cannabis and Cannabinoid Research -- helped identify compounds that could be tested further to understand their anti-cancer properties.

"Now that we've identified the compounds that we think have this activity, we can take these compounds and start trying to alter them to make them more potent against cancer cells," Vrana said. "And then eventually, we can explore the potential for using these compounds to develop drugs for treating cancer."

Colorectal cancer is one of the most common cancers diagnosed in the United States, according to the National Cancer Institute, with an estimated 140,250 newly diagnosed cases and 50,630 deaths in 2018. While medical cannabis has largely been used in recent years for palliative care, the researchers said some previous studies suggested that certain cannabinoid compounds may have the potential to inhibit or prevent the growth of tumors.

To explore how effective cannabinoids were at reducing the viability of colon cancer cells specifically, the researchers tested how 370 different synthetic cannabinoid compounds affected seven types of human colon cancer cells.

"There are many different ways cells can become cancerous," Vrana said. "Each of the seven cells we tested had a different cause or mutation that led to the cancer, even though they were all colon cells. We didn't want to test these compounds on just one mutation or pathway to cancer."

The researchers incubated the cancer cells in a lab for eight hours before treating them with the cannabinoid compounds for 48 hours. Any compounds that showed signs of reducing the viability of one kind of cancer cell was then used to treat all seven kinds of cells.

After further screening and analysis, the researchers identified 10 compounds that inhibited the growth of almost all seven types of colon cancer types tested. But while the researchers were able to identify these compounds, Vrana said they are still unsure about how exactly the compounds worked to reduce the viability of the cancer cells.

"The 10 compounds we found to be effective fall into three classes, so they're similar to each other but with small changes," Vrana said. "We know how one of them works, which is by inhibiting the division of cells in general. We also found that the most potent and effective compounds don't seem to work through traditional marijuana receptors, although we're not sure of the exact mechanism yet."

Vrana said certain types of cells, like skin and colon cells, are more susceptible to cancers because they divide very frequently: "Every time a cell divides, there's the chance that it will mutate and keep dividing when it shouldn't, which is how cancers can start. So if we block that signal that's telling cancer cells to continue to divide, that could be a way to stop that cancer."

Vrana said that because the other compounds did not seem to be working through traditional cannabinoid signaling pathways, future research will focus on better understanding how the compounds interact with cancer cells and whether researchers can make the compounds more potent and effective.

Story Source:

Materials provided by Penn State. Original written by Katie Bohn. Note: Content may be edited for style and length.

Journal Reference:

Wesley M. Raup-Konsavage, Megan Johnson, Christopher A. Legare, Gregory S. Yochum, Daniel J. Morgan, Kent E. Vrana. Synthetic Cannabinoid Activity Against Colorectal Cancer Cells. Cannabis and Cannabinoid Research, 2018; 3 (1): 272 DOI: 10.1089/can.2018.0065

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Vitamin D and immune cells stimulate bone marrow disease

Date: February 8, 2019 Source: Kobe University Summary: The bone marrow disease myelofibrosis is stimulated by excessive signaling from vitamin D and immune cells known as macrophages, reveals a research team. These findings could help to develop alternative treatments that do not target problem genes.

(left column) The bone marrow of wild-type mice is formed of round blood cells. (right column) The bone marrow of mice with vitamin D receptors knocked out is occupied by spindle-shaped fibroblasts and collagen fibers, shows myelofibrosis. (left column) The bone marrow of wild-type mice is formed of round blood cells. (right column) The bone marrow of mice with vitamin D receptors knocked out is occupied by spindle-shaped fibroblasts and collagen fibers, shows myelofibrosis.

Credit: Kobe University

The bone marrow disease myelofibrosis is stimulated by excessive signaling from vitamin D and immune cells known as macrophages, reveals a Japanese research team. These findings could help to develop alternative treatments that do not target problem genes. The team was led by Research Fellow Kanako Wakahashi and Junior Associate Professor Yoshio Katayama (Kobe University Graduate School of Medicine) and the findings were published on February 4 in the online edition of Blood.

There are three types of blood cell: white blood cells, red blood cells, and platelets. All three types are created from hematopoietic stem cells located in the bone marrow. Myelofibrosis causes an abnormal increase in the cells that produce collagen fibers called fibroblasts. The bone marrow becomes filled with these fibers, preventing the body from producing blood cells as normal. This condition can make it hard to control other diseases, and bone hardening (osteosclerosis) also occurs. Myelofibrosis occurs in blood tumors called myeloproliferative neoplasms, which are caused by genetic mutations of hematopoietic stem cells.

The research team focused on the relationship between blood and bone. Vitamin D is a hormone that regulates calcium, and the team had already shown that vitamin D receptors control the location of hematopoietic cells in the bone marrow. In this study, the team performed a bone marrow (with vitamin D receptors) transplant for a mouse model without vitamin D receptors (this means it has a high concentration of vitamin D in the body) to create a myelofibrosis model. By analyzing this model, they found that hematopoietic stem cells were strongly stimulated by vitamin D signaling and grew into immune system cells called macrophages. These pathological macrophages stimulated young osteoblasts (cells that create bone) to induce myelofibrosis and bone hardening. The cells known as fibroblasts are thought to be these young osteoblasts. By giving these mice a low vitamin D diet and suppressing the macrophages, the team was able to largely prevent the onset of myelofibrosis.

The team also examined mouse models with the same genetic disorder as myelofibrosis patients (JAK2V61F transgenic mice). These mice presented similar symptoms to myelofibrosis patients, displaying both fibrosis and bone hardening. They treated the mice by rearing them on a low vitamin D diet, blocking vitamin D receptor signals (removing the vitamin D receptor gene in blood cells) and suppressing macrophages. This proved to be extremely effective in preventing bone marrow fibrosis.

The results show that pathological macrophages produced by vitamin D receptor signaling play an important role in the development of myelofibrosis. Clinical treatment uses inhibitors to target the causative genes of myeloproliferative tumors, but this is not always effective in treating myelofibrosis. Professor Katayama comments: "The only permanent cure for this disease is hematopoietic stem cell transplant, but this method is unsuitable for many elderly patients. These new findings may help to develop a treatment method for the elderly targeting the vitamin D pathway and macrophages."

Story Source:

Materials provided by Kobe University. Note: Content may be edited for style and length.

Journal Reference:

Kanako Wakahashi, Kentaro Minagawa, Yuko Kawano, Hiroki Kawano, Tomohide Suzuki, Shinichi Ishii, Akiko Sada, Noboru Asada, Mari Sato, Shigeaki Kato, Kotaro Shide, Kazuya Shimoda, Toshimitsu Matsui, Yoshio Katayama. Vitamin D receptor-mediated skewed differentiation of macrophages initiates myelofibrosis and subsequent osteosclerosis. Blood, 2019; blood-2018-09-876615 DOI: 10.1182/blood-2018-09-876615

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REDE PANCS BAHIA

How a fungus can cripple the immune system

Research team clarifies the mechanism of gliotoxin, a mycotoxin from the fungus Aspergillus fumigatus

Date: February 8, 2019 Source: Friedrich-Schiller-Universitaet Jena Summary: Scientists have now discovered how the fungus knocks out the immune defenses, enabling a potentially fatal fungal infection to develop.

It is everywhere -- and it is extremely dangerous for people with a weakened immune system. The fungus Aspergillus fumigatus occurs virtually everywhere on Earth, as a dark grey, wrinkled cushion on damp walls or in microscopically small spores that blow through the air and cling to wallpaper, mattresses and floors. Healthy people usually have no problem if spores find their way into their body, as their immune defence system will put the spores out of action. However, the fungus can threaten the lives of people with a compromised immune system, such as AIDS patients or people who are immunosuppressed following an organ transplantation.

An international research team led by Prof. Oliver Werz of Friedrich Schiller University, Jena, has now discovered how the fungus knocks out the immune defences, enabling a potentially fatal fungal infection to develop. The researchers present their findings in the current issue of the specialist journal Cell Chemical Biology.

Among other factors, it is gliotoxin -- a potent mycotoxin -- that is responsible for the pathogenicity of Aspergillus fumigatus. "It was known," says study manager Werz of the Institute of Pharmacy at the University of Jena, "that this substance has an immunosuppressive effect, which means that it weakens the activity of cells of the immune defence system." However, it had not been clear previously how exactly this happens. Werz and his team colleagues have now studied this in detail and have clarified the underlying molecular mechanisms.

Immune cells communicate with one another

To achieve this, the researchers brought immune cells into contact with synthetically produced gliotoxin. These cells, called neutrophilic granulocytes, represent the first line of the immune defence system. "Their task is to detect pathogens and eliminate them," explains Werz. As soon as such a cell comes into contact with a pathogen, for example a fungus, it releases specific messenger substances (leukotrienes) into the blood, which attract other immune cells. Once a sufficiently large number of immune cells has gathered, they can render the intruder harmless.

Mycotoxin switches off enzyme

This does not happen if the pathogen Aspergillus fumigatus is involved. As the Jena scientists were able to show, gliotoxin ensures that production of the messenger substance leukotrieneB4 in the neutrophilic granulocytes is inhibited, so that they are unable to send a signal to other immune cells. This is caused by a specific enzyme (LTA4 hydrolase) being switched off by the mycotoxin. "This interrupts communication between the immune cells and destroys the defence mechanism. As a result, it is easy for spores -- in this case the fungus -- that enter the organism to infiltrate tissues or organs," says Werz.

Cooperation in Cluster of Excellence 'Balance of the Microverse'

For their study, Prof. Werz and his colleagues collaborated with researchers from the Leibniz Institute for Natural Product Research and Infection Biology (Hans Knöll Institute). As part of the Collaborative Research Centre ChemBioSys and the Jena Cluster of Excellence 'Balance of the Microverse', they cooperated with the working groups led by Prof. Axel Brakhage and Prof. Christian Hertweck, which contributed their expertise in mycology and natural product synthesis. Additional partners are research groups from the Universities of Frankfurt and Naples, as well as the Karolinska Institute in Stockholm.

Story Source:

Materials provided by Friedrich-Schiller-Universitaet Jena. Note: Content may be edited for style and length.

Journal Reference:

Koenig S et al. Gliotoxin from Aspergillus fumigatus Abrogates Leukotriene B4 Formation through Inhibition of Leukotriene A4 Hydrolase. Cell Chemical Biology, 2019 DOI: 10.1016/j.chembiol.2019.01.001

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Friedrich-Schiller-Universitaet Jena. "How a fungus can cripple the immune system: Research team clarifies the mechanism of gliotoxin, a mycotoxin from the fungus Aspergillus fumigatus." ScienceDaily. ScienceDaily, 8 February 2019. <www.sciencedaily.com/releases/2019/02/190208095614.htm>.

Complementary medicine use remains hidden from conventional medicine providers

Date: February 8, 2019 Source: University of Technology Sydney Summary: Research reveals that 1 in 3 complementary medicine (CM) users do not disclose their CM use to their medical providers, posing significant direct and indirect risks of adverse effects and harm due to unsafe concurrent use of CM and conventional medicine use.

Research reveals that 1 in 3 complementary medicine (CM) users do not disclose their CM use to their medical providers, posing significant direct and indirect risks of adverse effects and harm due to unsafe concurrent use of CM and conventional medicine use.

The first international systematic review conducted by researchers at the Australian Research Centre in Complementary and Integrative Medicine provides an update on the prevalence and characteristics of disclosure of CM use to medical providers since previous research conducted in 2003.

"This figure has hardly changed since the last review of the topic 13 years ago. This is despite the fact that the authors of every paper included in our review called for improved communication between doctors and patients to facilitate better disclosure," says lead author and PhD candidate Hope Foley.

The study found that disclosure of CM use to medical providers is influenced by the providers' communication style. Perceived provider knowledge of CM use was reported to be a barrier to discussions about CM use in clinical consultations.

When the actual response of the provider to disclosure of CM use was explored by researchers, negative or discouraging responses were reported by less than 20% of disclosers or were not reported at all. Positive or encouraging responses to disclosure of CM use by a medical doctor were reported by a substantial proportion of respondents and neutral responses from medical providers were also common.

More than 67% of participants agreed that disclosure was important.

"Patient autonomy and preference are important features of person-centered care to be considered by medical providers alongside safety and treatment outcomes in their patient management," the authors write.

On a global public health level, the World Health Organisation recognises the importance of integrated care which encompasses CM. Yet public health policies and procedures often create barriers to effective integration, limiting appropriate management of concurrent use and access to the recognised benefits of integrated care."

"As CM becomes more As CM becomes more separate from mainstream health services, disclosure is only going to become more and more important for public safety."

The researchers conclude that in the context of contemporary person-centred health care models, discussions and subsequent disclosure of CM use may be facilitated by direct inquiry about CM use by providers.

"This is a topic which should be treated with gravity," the researchers say. "Disclosure of CM use is central to wider patient management and care in contemporary clinical settings, particularly for primary care providers acting as gatekeeper in their patients' care."

Story Source:

Materials provided by University of Technology Sydney. Note: Content may be edited for style and length.

Journal Reference:

H. Foley, A. Steel, H. Cramer, J. Wardle, J. Adams. Disclosure of complementary medicine use to medical providers: a systematic review and meta-analysis. Scientific Reports, 2019; 9 (1) DOI: 10.1038/s41598-018-38279-8

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University of Technology Sydney. "Complementary medicine use remains hidden from conventional medicine providers." ScienceDaily. ScienceDaily, 8 February 2019. <www.sciencedaily.com/releases/2019/02/190208095619.htm>.

How poppy flowers get those vibrant colors that entice insects

Date: February 8, 2019 Source: University of Groningen Summary: With bright reds and yellows -- and even the occasional white -- poppies are very bright and colorful. Their petals, however, are also very thin; they are made up of just three layers of cells. Scientists used microscopy and mathematical models describing how light interacts with petals to find out how the vibrant colors are created. 

Different poppies which were used in the study. 

Credit: University of Groningen 

With bright reds and yellows -- and even the occasional white -- poppies are very bright and colorful. Their petals, however, are also very thin; they are made up of just three layers of cells. University of Groningen scientists Casper van der Kooi and Doekele Stavenga used microscopy and mathematical models describing how light interacts with petals to find out how the vibrant colors are created. The results will be included in a special edition of the Journal of Comparative Physiology A, which focuses on the relationship between insects and flowers. 

Van der Kooi's main research focus is the evolution of flower color, and the interaction between flower color and pollinators. This led him to investigate how petals produce their visual signals. He explains why the flowers of poppies (Papaver, Meconopsis and related species) are interesting: 'The common poppy is an extreme case, it has very thin petals that nevertheless cause a very high scattering of light. Poppies also contain high concentrations of pigments.' 

Jigsaw pieces 

The researchers collected petals from different poppy species and studied their structures using different techniques. They discovered that the pigment was only present in the two outer cell layers and not in the middle layer. The pigmented cells had a fascinating shape, with many invaginations that made them look like complicated jigsaw pieces. 'This creates many air-filled gaps between the cells, which cause the reflection of light on the cell/air boundary', says Van der Kooi. 

Furthermore, the petals contained huge amounts of pigment. 'They are among the highest concentrations that I have ever measured in any flower.' Indeed, the characteristic black markings at the center of some poppy flowers are caused by extreme concentrations of red pigment. Van der Kooi concludes that dense pigmentation together with strong scattering causes the striking poppy colors in the red parts of the petal. 

Sexual mimicry 

The new findings can be linked to previous work on poppy color evolution. Intriguingly, poppies in the Middle East reflect no ultraviolet light, while the same species in Europe do. This difference may be due to their preferred pollinators. 'In Europe, poppies are pollinated mostly by bees, which cannot see red very well; however, they will pick up ultraviolet.' In contrast, poppies in the Middle East are pollinated by beetles that do see red colors. 

'Moreover, previous studies have shown that the black spots at the heart of some poppies mimic the presence of a female beetle. This is a way for the flowers to attract male beetles. A case of sexual mimicry, as occurs in other plants such as orchids', explains Van der Kooi. 

Air gaps 

The next question will be how these jigsaw-like cells and the air gaps that cause the efficient scattering have evolved. 'These cell shapes are commonly present in leaves, so that might be a clue.' Furthermore, results suggest that poppies evolved ultraviolet signals when they began growing in more northern regions. It makes the evolutionary history of these brightly colored flowers an interesting object of study. 

The paper by Van der Kooi and Stavenga will be included in a special edition of the Journal of Comparative Physiology A, edited by Friedrich Barth (University of Vienna). This special edition, with the title "Insects and Flowers. New insights into an old partnership," is due to appear in print late this spring. The paper has already been published online. 

Story Source: 

Materials provided by University of Groningen. Note: Content may be edited for style and length. 

Journal Reference: 

Casper J. van der Kooi, Doekele G. Stavenga. Vividly coloured poppy flowers due to dense pigmentation and strong scattering in thin petals. Journal of Comparative Physiology A, 2019; DOI: 10.1007/s00359-018-01313-1

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Trevos e oxalato

Texto:

Marcos Roberto Furlan - Eng. Agrônomo - UNITAU/FIC

Mariane Belfort dos Santos - acadêmica de Nutrição - UNITAU 

Apesar do consumo condensado de vegetais, no que diz respeito a diversidade, ao redor do ser humano, como em calçadas e terrenos baldios, nascem espécies com potencial alimentício. Por não comporem parte comumente da nossa alimentação, estes vegetais são denominados de plantas alimentícias não convencionais (Pancs). 

No entanto, há alguns malefícios quanto ao consumo. São escassas as pesquisas sobre os seus valores nutricionais e muitas destas espécies desenvolveram mecanismos eficiente de defesa contra predadores e parasitas. 

Estes mecanismos podem ser, por exemplo, substâncias químicas tóxicas ao predador ou parasita, ou barreiras físicas como presença de cristais de oxalato ou uma camada de silício. 

Uma das substâncias é o ácido oxálico. Este composto tem relação com a formação de cálculos, devido à deposição de cristais de oxalato de cálcio nos rins. O ânion, oxalato, ao se ligar aos íons metálicos, forma precipitados insolúveis com destaque para o oxalato de cálcio, que é o principal constituinte da forma mais comum de cálculos renais. O ácido oxálico também pode causar lesão renal. 

Outros minerais que podem ser ligar ao ácido oxálico são o ferro e o magnésio. 

Ao ingerir alimentos ricos em oxalato, o indivíduo pode ter hiperoxalúria, com formação subsequente dos cristais de oxalato de cálcio insolúvel (elemento primário de cálculos renais). 

Como excentricidade, apesar de efeitos tóxicos no organismo, o ácido oxálico tem diversas aplicações, como, por exemplo, para eliminar ferrugem de metais, para fixar corantes em tecidos. Por essa razão é usado em várias preparações de produtos de limpeza. 

Mas qual a relação de oxalatos com o trevo? O fundamento da nomenclatura oxalato é por ser derivada do gênero Oxalis. Muitas das espécies deste gênero são designadas popularmente de trevo e são consideradas ricas em oxalato. Portanto, o consumo dos trevos deve ser feito em pequenas quantidades, principalmente devido ao fato de serem consumidos crus. O cozimento reduz significativamente os teores de oxalato, mas o consumo de trevos é geralmente na forma crua. 

Outros alimentos em que o ácido oxálico pode ser encontrado são: espinafre, azedinha, tomate, inhame, carambola e outros, sendo estes mais conhecidos e consumidos rotineiramente. 

Foto: trevos são comuns nos quintais, se desenvolvendo entre as ornamentais ou nos canteiros de hortaliças. 

Autoria da foto: Mariane Belfort dos Santos

Algumas referências sobre trevos do gênero Oxalis 

IBRAHIM, Muhammad et al. Corniculatin A, a new flavonoidal glucoside from Oxalis corniculata. Revista Brasileira de Farmacognosia, [s.l.], v. 23, n. 4, p.630-634, jul. 2013. Elsevier BV. http://dx.doi.org/10.1590/s0102-695x2013005000059. 

ROGERIO FIORUCCI, Antonio. et al. Ácidos Orgânicos: dos Primórdios da Química Experimental à sua Presença em Nosso Cotidiano. Química Nova na Escola, n. 15, mai. 2002. Acesso em: 07 de fev. 2019. Disponível em: https://repositorio.bc.ufg.br/xmlui/bitstream/handle/ri/15850/Artigo%20-%20Antonio%20Rog%C3%A9rio%20Fiorucci%20-%202002.pdf?sequence=5&isAllowed=y

ROSENFELDT, Sonia; GALATI, Beatriz Gloria. Morphology of the seed coat of Oxalis spp. from Buenos Aires Province (Argentina). Turkish Journal Of Botany, [s.l.], v. 38, p.864-876, 2014. The Scientific and Technological Research Council of Turkey. http://dx.doi.org/10.3906/bot-1311-12. 

SANGKETKIT, C. et al. Oxalate Content of Raw and Cooked Oca (Oxalis tuberosa). Journal Of Food Composition And Analysis, [s.l.], v. 14, n. 4, p.389-397, ago. 2001. Elsevier BV. http://dx.doi.org/10.1006/jfca.2000.0982. 

SEAL, S. N.; SEN, S. P.. The photosynthetic production of oxalic acid in Oxalis corniculata. Plant And Cell Physiology, [s.l.], v. 11, n. 1, p.119-128, fev. 1970. Oxford University Press (OUP). http://dx.doi.org/10.1093/oxfordjournals.pcp.a074483. 

A very small number of crops are dominating globally: That's bad news for sustainable agriculture

Date: February 6, 2019 Source: University of Toronto Summary: A new study finds that globally we're growing more of the same kinds of crops, and this presents major challenges for agricultural sustainability on a global scale.

Soybeans (pictured above) are among a small handful of crops that are dominating global agriculture, and that's not a good development for sustainable agriculture says U of T environmental scientist Adam Martin.

Credit: University of Toronto Scarborough

A new U of T study suggests that globally we're growing more of the same kinds of crops, and this presents major challenges for agricultural sustainability on a global scale.

The study, done by an international team of researchers led by U of T assistant professor Adam Martin, used data from the U.N.'s Food and Agricultural Organization (FAO) to look at which crops were grown where on large-scale industrial farmlands from 1961 to 2014.

They found that within regions crop diversity has actually increased -- in North America for example, 93 different crops are now grown compared to 80 back in the 1960s. The problem, Martin says, is that on a global scale we're now seeing more of the same kinds of crops being grown on much larger scales.

In other words, large industrial-sized farms in Asia, Europe, North and South America are beginning to look the same.

"What we're seeing is large monocultures of crops that are commercially valuable being grown in greater numbers around the world," says Martin, who is an ecologist in the Department of Physical and Environmental Sciences at U of T Scarborough.

"So large industrial farms are often growing one crop species, which are usually just a single genotype, across thousands of hectares of land."

Soybeans, wheat, rice and corn are prime examples. These four crops alone occupy just shy of 50 per cent of the world's entire agricultural lands, while the remaining 152 crops cover the rest.

It's widely assumed that the biggest change in global agricultural diversity took part during the so-called Columbia exchange of the 15th and 16th centuries where commercially important plant species were being transported to different parts of the world.

But the authors found that in the 1980s there was a massive increase in global crop diversity as different types of crops were being grown in new places on an industrial scale for the first time. By the 1990s that diversity flattened out, and what's happened since is that diversity across regions began to decline.

The lack of genetic diversity within individual crops is pretty obvious, says Martin. For example, in North America, six individual genotypes comprise about 50 per cent of all maize (corn) crops.

This decline in global crop diversity is an issue for a number of reasons. For one, it affects regional food sovereignty. "If regional crop diversity is threatened, it really cuts into people's ability to eat or afford food that is culturally significant to them," says Martin.

There is also an ecological issue; think potato famine, but on a global scale. Martin says if there's increasing dominance by a few genetic lineages of crops, then the global agricultural system becomes increasingly susceptible to pests or diseases. He points to a deadly fungus that continues to devastate banana plantations around the world as an example.

He hopes to apply the same global-scale analysis to look at national patterns of crop diversity as a next step for the research. Martin adds that there's a policy angle to consider, since government decisions that favour growing certain kinds of crops may contribute to a lack of diversity.

"It will be important to look at what governments are doing to promote more different types of crops being grown, or at a policy-level, are they favouring farms to grow certain types of cash crops," he says.

The study, which is published in the journal PLOS ONE, received funding from the Natural Sciences and Engineering Research Council of Canada (NSERC).

Story Source:

Materials provided by University of Toronto. Original written by Don Campbell. Note: Content may be edited for style and length.

Journal Reference:

Adam R. Martin, Marc W. Cadotte, Marney E. Isaac, Rubén Milla, Denis Vile, Cyrille Violle. Regional and global shifts in crop diversity through the Anthropocene. PLOS ONE, 2019; 14 (2): e0209788 DOI: 10.1371/journal.pone.0209788

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Phthalates may impair fertility in female mice

Date: February 7, 2019

Source: University of Illinois at Urbana-Champaign

Summary:

A phthalate found in many plastic and personal care products may decrease fertility in female mice, a new study found. Researchers found that giving female mice oral doses of the phthalate DiNP for 10 days disrupted their estrus cycles, decreasing their ability to become pregnant for up to nine months afterward.

See more at:

https://www.sciencedaily.com/releases/2019/02/190207150036.htm

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