what's the buzz

what's the buzz

Simple blood test to help spot Alzheimer’s onset

In a major breakthrough in the world of medical research, researchers claimed to have developed a way to identify people at high risk of cognitive decline or Alzheimer’s within 3 years through a simple blood test.

The study heralds the potential for developing treatment strategies for Alzheimer’s at an earlier stage, when therapy would be more effective at slowing or preventing onset of symptoms. It is the first known published report of blood-based biomarkers for preclinical Alzheimer’s. The test identifies 10 lipids in the blood that predict disease onset. It could be ready for use in clinical studies in as few as two years and other diagnostic uses are possible.

The study included 525 healthy participants aged 70 and older who gave blood samples upon enrolling and at various points in the study.

A panel of 10 lipids was discovered, which researchers say appears to reveal the breakdown of neural cell membranes in participants who develop symptoms of cognitive impairment or AD.

The panel was subsequently validated using the remaining 21 aMCI/AD participants (including 10 converters), and 20 controls. Blinded data were analysed to determine if the subjects could be characterised into the correct diagnostic categories based solely on the 10 lipids identified in the discovery phase. The lipid panel was able to distinguish with 90 percent accuracy these two distinct groups: cognitively normal participants who would progress to MCI or AD within two to three years, and those who would remain normal in the near future.

Stem cell therapy for degenerative disc disease

Researchers have said that recent development in stem cell research could help treat degenerative disc disease.

Senior author, Wenchun Qu, MD, PhD, of the Mayo Clinic in Rochester, Minnesota, said that this landmark study draws the conclusion in pre-clinical animal studies that stem cell therapy for disc degenerative disease might be a potentially effective treatment for the very common condition that affects people’s quality of life and productivity.
Dr Qu said not only did disc height increase, but stem cell transplant also increased disc water content and improved appropriate gene expression.

He said these developments place us in a position to prepare for translation of stem cell therapy for degenerative disc disease into clinical trials.

The increase in disc height was due to restoration in the transplant group of the nucleus pulposus structure, which refers to the jelly-like substance in the disc, and an increased amount of water content, which is critical for the appropriate function of the disc as a cushion for the spinal column.

The researchers performed a literature search of MEDLINE, EMBASE and PsycINFO databases and also manually searched reference lists for original, randomised, controlled trials on animals that examined the association between IVD stem cell transplant and the change of disc height. Six studies met inclusion criteria. Differences between the studies necessitated the use of random-effects models to pool estimates of effect.

How antibiotic resistance spreads among bacteria

Researchers have uncovered the system that allows the sharing of genetic material between bacteria – and therefore the spread of antibiotic resistance.

The study by researchers at Birkbeck, University of London and UCL revealed the mechanism of bacterial type IV secretion, which bacteria use to move substances across their cell wall.

As type IV secretion can distribute genetic material between bacteria, notably antibiotic resistance genes, the mechanism is directly responsible for the spread of antibiotic resistance in hospital settings.

It also plays a crucial role in secreting toxins in infections - causing ulcers, whooping cough, or severe forms of pneumonia such as Legionnaires’ disease.

The work revealed that the type IV secretion system differs substantially from other bacterial secretion systems, in both its molecular structure and the mechanism for secretion.

Using electron microscopy the team were able to reconstruct the system as observed in the bacteria E coli. They saw that the mechanism consists of two separate complexes, one in the outer membrane of the cell, and the other in the inner membrane, which are connected by a stalk-like structure that crosses the periplasm.
The complexes at both the inner and outer membranes form pores in the membrane, via which substances can be secreted.

Understanding the structure of the secretion system will help scientists uncover the mechanism by which it moves substances across the inner and outer membranes, and develop new tools for the genetic modification of human cells, as the bacteria could act as a carrier for genetic material, which could then be secreted into cells.