Inicio Blog Página 15

Scientists find a role for Parkinson’s gene in the brain

0

For more than 10 years, scientists have known that mutations in the LRRK2 gene can lead to Parkinson’s disease, yet both its role in the disease and its normal function in the brain remain unclear. In a study in mice, researchers have now found that LRRK is necessary for the survival of dopamine-containing neurons in the brain, the cells most affected by Parkinson’s. Importantly, this finding could alter the design of treatments against the disease.

“Since its discovery, researchers have been trying to define LRRK2 function and how mutations may lead to Parkinson’s disease,” said Beth-Anne Sieber, Ph.D., program director at NINDS. “The findings in this paper emphasize the importance of understanding the normal role for genes associated with neurodegenerative disorders.”

LRRK2 is found along with a closely related protein, LRRK1, in the brain. A mutation in LRRK2 alone can eventually produce Parkinson’s disease symptoms and brain pathology in humans as they age. In mice, however, LRRK2 loss or mutation does not lead to the death of dopamine-producing neurons, possibly because LRRK1 plays a complementary or compensatory role during the relatively short, two-year mouse lifespan.

“Parkinson’s-linked mutations such as LRRK2 have subtle effects that do not produce symptoms until late in life. Understanding the normal function of these types of genes will help us figure out what has gone wrong to cause disease,” said Jie Shen, Ph.D., director of the NINDS Morris K. Udall Center of Excellence for Parkinson’s Disease at Brigham and Women’s Hospital and senior author of this study.

To better understand the roles of these related proteins in brain function using animal models, Shen and her colleagues created mice lacking both LRRK1 and LRRK2. They observed a loss of dopamine-containing neurons in areas of the brain consistent with PD beginning around 15 months of age. When the researchers looked at the affected brain cells more closely, they saw the buildup of a protein called α-synuclein, a hallmark of Parkinson’s, and defects in pathways that clear cellular “garbage.” At the same time, more dopamine-containing neurons also began to show signs of apoptosis, the cells’ “self-destruct” mechanism.

“Our findings show that LRRK is critical for the survival of the populations of neurons affected by Parkinson’s disease,” said Dr. Shen.

While the deletion of both LRRK1 and LRRK2 did not affect overall brain size or cells in such areas of the brain as the cerebral cortex and cerebellum, the mice showed other significant effects such as a decrease in body weight and a lifespan of only 15 to 16 months. Thus, the scientists were unable to study other Parkinson’s-related effects such as changes in behavior and movement nor were they able to conduct a long-term analysis of how LRRK’s absence affects the brain.

Interestingly, the most common disease-linked mutation in LRRK2 is thought to make the protein more active. As a result, most efforts to develop a treatment against that mutation have focused on inhibiting LRRK2 activity.

“The fact that the absence of LRRK leads to the death of dopamine-containing neurons suggests that the use of inhibitory drugs as a treatment for Parkinson’s disease might not be the best approach,” said Dr. Shen.

Dr. Shen and her colleagues are now developing mice that have LRRK1 and 2 removed only in the dopamine-containing neurons of the brain. This specific deletion will allow the researchers to study longer-term and behavioral changes while avoiding the other consequences that lead to a shortened lifespan.

This study was supported by the NINDS (NS071251, NS094733).

The NINDS is the nation’s leading funder of research on the brain and nervous system. The mission of NINDS is to seek fundamental knowledge about the brain and nervous system and to use that knowledge to reduce the burden of neurological disease.

About the National Institutes of Health (NIH): NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.

Source: NIH

Listado de emisiones anteriores

No se encontraron entradas.

Hepatic fibrosis assessment using multiparametric biomarker tests

0

An ELFM’s webinar recorded on 18th October 2017.

Speaker: Ralf Lichtinghagen (GER)

Moderator: Merve Sibel Gungoren (TR)

The stage of fibrosis is the most important single predictor of significant morbidity and mortality in chronic liver disease. The mechanisms leading to fibrosis and eventually cirrhosis are thought to be similar, irrespective of the underlying etiology. At cellular level, hepatic stellate cells (HSC) undergo a phenotypic switch usually addressed as transactivation. Activated HSC are regarded as the main source of extracellular matrix (ECM) in the fibrotic liver. Additional cell types namely fibroblasts and myofibroblasts may also contribute to ECM deposition.

Despite the similarities in pathophysiology at cellular level, morphogenesis and histologic appearance of the fibrotic liver may differ according to the etiology. Liver biopsy remains the gold standard to evaluate liver fibrosis. Not least, one has to keep in mind that liver biopsy provides additional information like histological grading and etiology that may be overlooked when surrogate markers are used.

Ideally, those tests should answer two questions:

  1. What is the stage of fibrotic organ damage (i.e. the amount of deposited ECM and the disturbed balance of hepatic microarchitecture)?
  2. What is the net balance between ECM deposition and degradation (i.e. the dynamics of ECM turnover)?

The former serves to evaluate the prognosis and indicate therapy, while the latter might be used to control the efficacy of treatment with regard to disease progression. Many different parameters including standard clinical chemistry and parameters of matrix metabolism have been evaluated.

In the last decade, markers were assembled to multiparametric scores. Here, we can distinguish scores assembled of standard clinical chemistry markers (e.g. aspartate aminotransferase-to-platelet ratio index, FibroTest, Forns’ index) from scores using circulating markers of hepatic matrix metabolism like hyaluronic acid (HA), tissue inhibitor of metalloproteinases-1 (TIMP-1), matrix metalloproteinase-2, propeptide of type III procollagen (PIIINP).

In the webinar we will learn further details about the relevant complex scores, the clinical evaluation and current practical guidelines.

Expanding our view of the human microbiome

0

In fact, it’s become increasingly clear that the healthy human body is teeming with microorganisms, many of which play essential roles in our metabolism, our immune response, and even our mental health. We are not just an organism, we are a “superorganism” made up of human cells and microbial cells—and the microbes outnumber us! Fueling this new understanding is NIH’s Human Microbiome Project (HMP), a quest begun a decade ago to explore the microbial makeup of healthy Americans.

About 5 years ago, HMP researchers released their first round of data that provided a look at the microbes present in the mouth, gut, nose, and several other parts of the body [1]. Now, their second wave of data, just published in the journal Nature, has tripled this treasure trove of information, promising to further expand our understanding of the human microbiome and its role in health and disease [2]. For example, the new DNA data offer clues as to the functional roles those microbes play and how those can vary over time in different parts of the human body and from one person to the next.

The human microbiome consists of a large, but still undetermined, number of microbes. While bacteria make up the majority of the bugs calling our bodies home, other residents include single-celled archaea and fungi. And there are several types of viruses, too, in the nose and gut of otherwise perfectly healthy people.

Collectively, these bugs express millions of microbial genes, called a metagenome. The new data set includes over a million more gene families from the metagenomes than the first HMP data release, as the latest samples captured a wider swath of microbial diversity.

Sequencing metagenomes allowed the researchers to consider the biochemical abilities and potential functions of the human microbiome. Although many genes and pathways in the microbiome are not yet biochemically characterized, 19 pathways were enriched across all of the body sites examined. That means they occur specifically in groups of microbes that are adapted to live in and on human beings.

Those relatively host-specific gene pathways are likely to point the way to functional adaptations important for the microbes’ ability to live in harmony with humans and even to provide benefits to their human hosts. For example, the microbial metagenomes found in multiple body sites appear to have a special ability to synthesize vitamin B12, which is essential to human health.

Other specialized features were specific to particular parts of the human body. For instance, microbes found in the mouth were enriched for genes involved in the chemical modification of nitrates in our diets to nitrites, a process that has been linked to blood pressure regulation and prevention of migraines, among other health conditions. Gut microbes have a special ability to break down mannan, a carbohydrate found in many vegetables.

There were other intriguing observations, too. Haemophilus parainfluenzae has long been known to inhabit the upper respiratory tract and play a role in bronchitis and sinusitis. But the researchers found unexpectedly the bacterium also resides in multiple parts of the mouth. The specific strain varied depending on whether the microbial sample was collected from a person’s cheek, tongue, or tooth surfaces. It suggests the H. parainfluenzae found on my cheek could be more similar to the one found on your cheek than it is to the one on my tongue!

Interestingly, researchers found no characteristic differences in the metagenomes of people in Houston and St. Louis, where study participants lived. Whether this holds for cities across the country will be fascinating to find out.

Some of the microbes in a particular person’s gut tended to remain stable over time, while others were much more variable. Surprisingly, however, those core microbes often varied considerably from one person to the next. In other words, the gut microbiomes of people—even those living in the very same city—can contain a highly personalized set of bugs with as-yet undetermined implications for our health.

In total, the new data include an additional 1,631 metagenomes, bringing the complete HMP collection to 2,355 metagenomes. The new metagenomes, gathered from 265 healthy volunteers, represent the complete set of microbial DNA sequences collected from each of six different body sites. These include the edge of the nostrils, inside of the cheek, surfaces of the teeth and tongue, gut, and, in women, a recess of the vagina found behind the cervix.

The latest data release was a true group effort, led by Curtis Huttenhower at the Harvard T.H. Chan School of Public Health, Boston, MA, and The Broad Institute, Cambridge, MA. The team also included Jason Lloyd-Price, also at The Broad Institute, and Anup Mahurkar at the University of Maryland Institute for Genome Sciences, Baltimore.

In addition to our genes, lifestyles, and experiences, our microbiomes are a part of what makes each of us unique. They may also help to explain why some people are more prone to certain illnesses than others. As we learn more in the coming years about the microbial differences that may predispose individuals to good health or illness, one thing is now abundantly clear: microbes are an essential part of us.

References:

  1. Structure, function and diversity of the healthy human microbiome. Human Microbiome Project Consortium. Nature. 2012 Jun 13;486(7402):207-14.
  2. Strains, functions, and dynamics in the expanded Human Microbiome Project. Nature. 2017 Sept 20.

Fuente: NIH

#Durban2017 The IFCC WorldLab Congress President’s invitation

0

Prof. Tahir Pillay, IFCC World Lab Congress Co-President and Chairman of the Scientific Programme Committee, invites the laboratory medicine community to go to this important IFCC event in Durban, South Africa, from October 22 to 25, 2017.

Congress web page

No more information is available on infobioquimica.org. For further requests, you can contact the organizers of the event.

#Durban2017 XIV ICPLM invitation

0

Prof. Vijay Grey, past Chair of the IFCC Task Force Paediatric Laboratory Medicine, invites laboratory medicine professionals to the XIV International Congress of Paediatric Laboratory Medicine, in Durban, South Africa, 20-22 October, 2017.

 

Download the Scientific Program (PDF)

Congress web page: www.icplm2017.org

 

No more information is available on infobioquimica.org. For further requests, you can contact the organizers of the event.

11th International Congress on Autoimmunity

0

Portugal has traditionally played a leading role in advancing knowledge about autoimmune diseases and the country has a very strong autoimmunologist community, composed of rheumatologists, internists, immunologists, nephrologists and others. The Faculty will include several highly respected local specialists, alongside a great number of international experts, sharing the common goal of spreading and exchanging knowledge about the latest developments in autoimmunity.

The International Congress on Autoimmunity is the largest multidisciplinary congress that discusses all aspects of the related diseases under one roof, offering courses and lectures by some of the world’s most distinguished experts. At the same time, the Congress prides itself on providing a stage for young upcoming talents to present their research to a first-rate audience.

CONGRESS VENUE

  • CCL – Centro de Congressos de Lisboa
  • Lisboa Congress Centre
  • Praça das Indústrias, 1300-307, Lisboa, Portugal

Web page: autoimmunity.kenes.com/2018/

No more information is available on infobioquimica.org. For further requests, you can contact the organizers of the event.

IFCC Satellite Educational Workshop on “Intelligent Clinical Laboratory Management: Impacts on Quality System Improvement”

0

IFCC Satellite Educational Workshop on “Intelligent Clinical Laboratory Management: Impacts on Quality System Improvement” will be held at the Hilton Durban Hotel, on October 22, 2017.

Attendance is limited to only 60 participants and open to practicing laboratory professionals, laboratory specialists, laboratory physicians, laboratory technicians, medical laboratory technologists, laboratory managers, supervisors and laboratory quality managers.

The objective of this educational workshop is to provide the attendees key strategical elements and best practices to optimize workflow within their laboratory in association with the quality management. It is designed so that the attendees will be prepared to return to their laboratories to strengthen their own practice and mentor their colleagues in this approach.

Scientific Programme

If you are interested, please register on line: CCLM_Workshop

For further information please contact:

#IFCCWorldLab2017 Satellite Symposium “Biomarkers for Diabetes”

0

International Scientific Committee of IFCC invites you to Cape Town to attend the Satellite Symposium “Biomarkers for Diabetes”, which will be held 26th to 27th October immediately following the IFCC Worldlab Durban 2017.

Aim: To address both clinical and laboratory advances in the diagnosis and management of diabetes.

Features:

  1. Many internationally renowned diabetes experts will be speaking at the symposium including past Presidents of the American Diabetes Association, European Association for the Study of Diabetes and The International Diabetes Federation, as well as the Chief Mission Officer of the JDRF.
  2. The program includes sessions on new therapies for diabetes, evidence-based guidelines, management of diabetes in low-income countries, bariatric surgery, and biomarkers including HbA1c, glucose meters, and new biomarkers.

 Download the Satellite Symposium Programme 

No more information is available on infobioquimica.org. For further requests, you can contact the organizers of the event.

IFCC Regional Representatives for 2018-2020

0

The IFCC Nominations Committee is happy to announce the IFCC Regional Representatives for 2018-2020. We warmly congratulate the newly elected IFCC Regional Federation Representatives to the IFCC Executive Board for the period January 1st, 2018 until December 31th 2020.

The Committee wish the new EB the best success to ensure the promotion of clinical chemistry and laboratory medicine world-wide, promoting the ‘added value’ of laboratory medicine to healthcare, enhancing international clinical collaboration and education and management support to developing countries, and communicating good laboratory medicine practices and patient safety.

Image Image Dr Adekunle Bashiru Okesina
Image ImageDr Abderrazek Hedhili
Image ImageDr Sunil Sethi
Image ImageDr Sverre Sandberg
Image ImageDr Rosa Sierra-Amor
Image ImageDr Ann Gronowski

The IFCC Executive Board 2018-2020, will be composed as follows:

  • PRESIDENT: Prof. Howard MORRIS (Australia)
  • PAST PRESIDENT: Prof. Maurizio FERRARI (Italy)
  • SECRETARY: Dr. David KINNIBURGH (Canada)
  • TREASURER: Prof. Tomris OZBEN (Turkey)

REGIONAL FEDERATIONS Representatives:

  • Prof. Adekunle Bashiru OKESINA (Nigeria) – African Federation of Clinical Chemistry (AFCC)
  • Prof. Abderrazek HEDHILI (Tunisia) – Arab Federation of Clinical Biology (AFCB)
  • Dr. Sunil SETHI (Singapore) Asia-Pacific Federation for Clinical Biochemistry and Laboratory Medicine (APFCB)
  • Prof. Sverre SANDBERG (Norway) European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)
  • Dr. Rosa SIERAA-AMOR (Mexico) – Latin-American Confederation of Clinical Biochemistry (COLABIOCLI)
  • Dr. Ann GRONOWSKI (USA) – North American Federation of Clinical Chemistry and Laboratory Medicine (NAFCC)

CORPORATE Representative: Dr. Rolf HINZMANN (Roche Diagnostics)

Agenda

       

Radio El Microscopio

Ze Xiong

Últimas notas publicadas