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A new study adds to the growing literature showing that motor neurons are not the only sites affected in amyotrophic lateral sclerosis, writes Dr. Leana Doherty.


Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease primarily affecting motor neurons. However, nonmotor manifestations, including sensory, cognitive, and autonomic impairments, increasingly have been reported. In the current study, investigators examined cutaneous innervation and its correlation with disease severity in patients with ALS using the Small Fiber Neuropathy Symptoms Inventory Questionnaire, nerve conduction studies, and distal leg, thigh, and fingertip (glabrous skin) punch biopsies. Patients with alternate diagnoses including endocrinopathies, autoimmune disorders, and vitamin deficiencies were excluded.

Among 149 participants with ALS (mean age, 63; median disease duration, 14.3 months), 35% experienced large-fiber or small-fiber sensory symptoms or both. The frequency of small-fiber symptoms was higher in patients with more severe disease based on King’s staging; scores increase on the scale from 1 to 5 with increasing regions involved. Nearly one quarter of patients had one or more sensory nerve action potential abnormalities. The density of Meissner corpuscles (MC) was reduced in most ALS patients (53÷100), and intraepidermal nerve fiber (IENF) density was reduced at all sites (5th percentile: at the leg, 58%; thigh, 78%) compared with healthy controls. While MC density decreased with increasing King’s stage, IENF density increased. Increasing IENF density on repeat thigh biopsies at 6 and 12 months was associated with shorter survival. The researchers postulated that this may reflect an upregulation of reparative pathways paralleling disease aggressiveness.

In a significant leap forward for quantum nanophotonics, a team of European and Israeli physicists has introduced a new type of polaritonic cavities and redefined the limits of light confinement. This pioneering work, detailed in a study published in Nature Materials, demonstrates an unconventional method to confine photons, overcoming the traditional limitations in nanophotonics.

Physicists have long been seeking ways to force photons into increasingly small volumes. The natural length scale of the is the wavelength and when a photon is forced into a cavity much smaller than the wavelength, it effectively becomes more “concentrated.” This concentration enhances interactions with electrons, amplifying quantum processes within the cavity.

However, despite significant success in confining light into deep subwavelength volumes, the effect of dissipation (optical absorption) remains a major obstacle. Photons in nanocavities are absorbed very quickly, much faster than the wavelength, and this dissipation limits the applicability of nanocavities to some of the most exciting quantum applications.

The MMU was the highlight of the STS-41B mission as demonstrated by the stunning mission photographs that graced the cover of Aviation Week & Space Technology, not once, not twice, but three times.

“Hoot” Gibson, the flight’s pilot, shot the photograph featured on the February 20, 1984, issue of the magazine from the crew cabin. Gibson remembered he was the only one on the crew that “had absolutely nothing to do” as McCandless made his way out into space, so he picked up a Hasselblad camera and began documenting the events. When he first looked through the camera’s viewfinder, he could not believe what an incredible sight it was to see McCandless untethered, floating above the Earth. Gibson wanted to capture what he was seeing and remembered how meticulous he was. For each photograph he took three light meter readings and checked the focus four times. In the crew’s photography training he learned that an off-kilter horizon looked wrong and was not pleasing to the eye. That presented a slight problem because Challenger was at a 28.5-degree inclination, so he “tilted the camera to put the horizon level in the pictures.”

A team of researchers at the Carl Gustav Carus Faculty of Medicine, TUD Dresden University of Technology, led by Prof. Frank Buchholz, has achieved a major breakthrough in genome editing technology. They’ve developed a cutting-edge method that combines the power of designer-recombinases with programmable DNA-binding domains to create precise and adaptable genome editing tools.

Traditional genome editing faced limitations in achieving ultimate precision until now. Prof. Buchholz’s team has broken through this barrier by creating what many have sought after: a zinc-finger conditioned recombinase. This innovative approach involves integrating a zinc-finger DNA-binding domain into specially designed recombinases. These enzymes remain inactive until the DNA-binding domain engages with its target site, adjacent to the recombinase binding area.

The significance of this achievement lies in the fusion of two key strengths: the targeting ease of programmable nucleases and the precise DNA editing capabilities of recombinases. This breakthrough overcomes existing limitations in genome editing techniques and holds vast promise for therapeutic gene editing and various biomedical applications.

For years, there has been a long-held belief that acute viral infections like Zika or COVID-19 are directly responsible for neurological damage, but researchers from McMaster University have now discovered that it’s the immune system’s response that is behind it.

The research, published on Feb. 5, 2024, in Nature Communications, was led by Elizabeth Balint, a Ph.D. student at McMaster, and Ali Ashkar, a professor with the Department of Medicine and the Canada Research Chair in Natural Immunity and NK Cell Function.

“We were interested in trying to understand why so many are associated with ,” says Balint. “Our evidence suggests that it’s not the virus itself that causes the damage, but a unique population of T cells, which are part of the immune system, that are actually responsible for the damage.”