Adverse Birth Outcomes and Agricultural Pesticide Use in the San Joaquin Valley of California

MedicalResearch.com Interview with:

Ashley Larsen, PhD Assistant professor Bren School of Environmental Science & Management University of California, Santa Barbara

Dr. Larsen

Ashley Larsen, PhD
Assistant professor
Bren School of Environmental Science & Management
University of California, Santa Barbara

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The relationship between pesticides and adverse birth outcomes has been recognized as an important question for quite some time, and there have been many good studies on the topic. Since randomly exposing people to different levels of pesticides is clearly unethical, researchers focused on the health consequences of non-occupational pesticide exposure often have to choose between detailed studies that follow a couple hundred or couple thousand individuals through pregnancy or larger scale studies that use easier to observe, but less accurate metrics of pesticide exposure (e.g. nearby crops or crop types). Here we tried to provide complementary insight by bridging the gap between detail and scale using detailed pesticide use data and individual birth certificate records for hundreds of thousands of births in an agriculturally dominated region of California. While we found negative effects of pesticide use on birth outcomes including low birth weight, preterm birth and birth abnormalities, these effects were generally in the magnitude of a 5-9% increase in probability of an adverse outcome, and only observed for individuals exposed to very high levels of pesticides.

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H. pylori May Increase Risk of Stomach Cancer By Turning On Subset of Stem Cells

MedicalResearch.com Interview with:
Michael Sigal PhD

Clinical scientist of the Charité — Universitätsmedizin Berlin
Investigator at the Max Planck Institute for Infection Biology 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: We have previously found that H. pylori can colonize gastric glands and that in colonized glands the epithelial turnover was increased. We wanted to characterize the mechanisms that control the gland turnover in the stomach.

We found that Axin2, a classic Wnt target gene, marks two different subpopulations of cells with stem cell properties, one of which is Lgr5-positive and the other one Lgr5-negative. Both populations are affected by Rspondin 3, that is produced in myofibroblasts right beneath the stem cell compartment. Rspondin is crucial for stem cell signaling and knockout of Rspondin 3 in myofibroblasts results in loss of Lgr5 and Axin2 expression. Once we increased the bioavailability of Rspondin, that now could also interact with cells outside of the stem cell compartment, we noticed that the number of Axin2 positive stem cells dramatically increased. Of interest, only Lgr5-negative cells expanded in number and proliferate more, while the Lgr5-positive cells remained silenced.

Infection with Helicobacter pylori leads to an expansion of Axin2-positive cells which is driven by increased expression of Rspondin3. Expansion of the long lived stem cell pool could be an explanation for how H. pylori infection increases the risk for gastric cancer.

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16 New Genetic Links To Longevity Discovered

MedicalResearch.com Interview with:

Dr. Zoltán Kutalik, PhD Group Leader Swiss Institute of Bioinformatics

Dr. Kutalik

Dr. Zoltán Kutalik, PhD
Group Leader
Swiss Institute of Bioinformatics
Assistant professor at the Institute of Social and Preventive Medicine

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Why do some of us live longer than others? While the environment in which we live – including our socio-economic status or the food we eat – plays the biggest part, about 20 to 30% of the variation in human lifespan comes down to our genome. Changes in particular locations in our DNA sequence, such as single-nucleotide polymorphisms (SNPs), could therefore hold some of the keys to our longevity. Until now, the most comprehensive studies had found only two hits in the genome.

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Is Human Lifespan Really Limited to 100 Years?

MedicalResearch.com Interview with:

Pr. Siegfried Hekimi PhD McGill University

Prof. Hekimi

Pr. Siegfried Hekimi PhD
McGill University

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: We analyzed data about the longest living individuals over the period of time during which the record can be trusted.

We found that there was no detectable plateauing of the maximum possible lifespan. This is consistent with not clearly observed plateau in the currently increasing average lifespan as well.

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Rapid Improvements Coming to Gene Editing Techniques

MedicalResearch.com Interview with:

Michael Farzan PhD Co-chair and Professor Department of Immunology and Microbiology  Florida Campus  The Scripps Research Institute Jupiter, Florida

Dr. Farzan

Michael Farzan PhD
Co-chair and Professor
Department of Immunology and Microbiology
Florida Campus
The Scripps Research Institute
Jupiter, Florida

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: CRISPR is system for immune protection of bacteria.  It has now been widely adopted for use in editing mammalian cells.  The most commonly used CRISPR effector protein is Cas9.  Cas9 binds a guide RNA to recognize a DNA target, for example an incoming virus infecting a bacterium, or a gene in a human chromosome.  In bacteria, Cas9 requires a second protein to clear the guide RNA from a longer “CRISPR array”, basically a string of guide RNAs.

We have been studying a CRISPR effector protein related to Cas9 called Cpf1.  In bacteria it was know that, unlike Cas9, Cpf1 could cleave a CRISPR array by itself, without assistance from a second protein.  We knew that if it could do the same thing in human cells, it would help to simplify a number of gene-editing applications.  We were able to show that Cas9 could indeed excise multiple guide RNAs from a single message RNA in human cells.  We further showed that this approach was more efficient than the previous ways that guide RNAs were generated for gene editing, even more so when multiple guide RNAs were needed.

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Baby Teeth Can Expose Toxic Levels of Minerals Associated With Autism

MedicalResearch.com Interview with:

Manish Arora, PhD Associate Professor Environmental Medicine & Public Health Icahn School of Medicine at Mount Sinai

Dr. Arora

Manish Arora, PhD
Associate Professor
Environmental Medicine & Public Health
Icahn School of Medicine at Mount Sinai

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Autism has both genetic and environmental risk factors. Our aim was to study if exposure to toxic metals, such as lead, or disruptions in the uptake of essential nutrient elements such as manganese or zinc would be related to autism risk. Furthermore, we were interested in not only understanding how much exposure had taken place but also which developmental periods were associated with increased susceptibility to autism risk.

Researchers suspect that the risk factors for autism start early in life, even prenatally, but measuring in utero exposures is technically very challenging. We used a newly developed technique that uses lasers to map growth rings in baby teeth (like growth rings in trees) to reconstruct the history of toxic metal and essential nutrient uptake. We applied this technology in samples collected from twins, including twins who were discordant for autism. This allowed us to have some control over genetic factors.

We found that twins with autism had higher levels of lead in their teeth compared to their unaffected twin siblings. They also had lower levels of zinc and manganese. The lower uptake of zinc was restricted to approximately 10 weeks before birth to a few weeks after birth, indicating that as a critical developmental period.

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Metformin Reverses Some Autism Symptoms In Animal Model

MedicalResearch.com Interview with:
Ilse Gantois, PhD

Research Associate
Dr. Nahum Sonenberg’s laboratory
Department of Biochemistry
McGill University

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Fragile X syndrome (FXS) is a neurodevelopmental disorder characterized by cognitive impairment and affects 1 in 4000 males and 1 in 6000 females. About 60% of persons with Fragile X also have autism spectrum disorder. FXS is caused by absence of Fragile X protein (FMRP), which results in hyperactivation of ERK (extracellular signal-regulated kinase) and mTORC1 (mechanistic target of rapamycin complex 1) signaling. We show that treatment with metformin, the most widely used FDA-approved antidiabetic drug, suppresses translation by inhibiting the ERK pathway, and alleviates a variety of behavioural deficits, including impaired social interaction and excessive grooming. In addition, metformin also reversed defects in dendritic spine morphogenesis and synaptic transmission.
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Beta-Blockers Reduce Heart Attack Size By Limiting Inflammation

MedicalResearch.com Interview with:

Borja Ibáñez MD Spanish National Centre for Cardiovascular Research Madrid

Dr. Ibáñez

Borja Ibáñez MD
Spanish National Centre for Cardiovascular Research
Madrid

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Acute myocardial infarction (heart attack) is a severe condition responsible for thousands of deaths every year and with important long-term consequences for survivors. Best treatment for acute myocardial infarction is a rapid coronary reperfusion.

Upon reperfusion, all inflammatory cells and mediators accumulated in the circulation during the infarction process, enter into the myocardium and causes an extra damage to the heart. Activated neutrophils play a critical role in this damage occurring upon reperfusion. The final size of infarction is the main determinant for mortality and long-term morbidity. The possibility of limiting the extent of infarcted tissue is of paramount importance.

Betablockers have been used in patients for more than 4 decades, mainly to treat arrhythmias and high blood pressure. Recently the same group of investigators demonstrated that the very early administration (i.e. during ambulance transfer to the hospital) of the betablocker “metoprolol” was able to reduce the size of infarction in patients. The mechanism by which metoprolol was protective in patients suffering a myocardial infarction was unknown.

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Potential Drug-Binding Site Against Zika Virus Identified

MedicalResearch.com Interview with:

Dr. Jikui Song PhD Assistant professor of biochemistry University of California, Riverside.

Dr. Jikui Song

Dr. Jikui Song PhD
Assistant professor of biochemistry
University of California, Riverside.

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Recent outbreak of Zika virus (ZIKV) has become a wordwide health concern. However, no vaccines or antiviral drugs against ZIKV are currently available. To explore potential druggable sites for ZIKV, we set out to determine the crystal structure of full-length ZIKV NS5, the molecular machinery responsible for the genomic replication of ZIKV.

The major findings of our study include the identification of a conserved domain conformation within flavivirus NS5 family, which may be important for functional regulation of flavivirus NS5. Furthermore, our structural analysis revealed a potential drug-binding site of ZIKV NS5, providing basis for future development of novel antivirals against ZIKV.

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26 Additional Genes Linked to Intellectual Disability Identified

MedicalResearch.com Interview with:
Dr. Muhammad Ayub MBBS, MRCPsych, MSc., MD

Professor of Psychiatry Chair Division of Developmental Disabilities
Department of Psychiatry Queens
University Kingston
Kingston ON Canada

MedicalResearch.com: What is the background for this study? 

Response: Intellectual Disability affects about 1 percent of the population worldwide. Genetics play a major role in its etiology. Better understanding of the genetic causes is a necessary step in development of improved diagnosis and treatment. Recessive inheritance where the affected child inherits a defective copy of a gene from both the parents is an important genetic mechanism for prevalence of the disease in populations where within family marriages are common. These types of marital bonds are common in South Asia and Middle Eastern countries. The families where parents are related are an effective resource to study recessive forms of Intellectual Disability.

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