Day: January 9, 2025

Categories : Antibiotics Diseases, Syndromes and ConditionsTags : Leave a comment

The Spread of a Highly Drug-resistant Cholera Strain

On By ModernMedia
Scanning electron micrograph image of cholera bacteria.

Scientists from the National Reference Center for Vibrios and Cholera at the Institut Pasteur, in collaboration with the Centre hospitalier de Mayotte, have revealed the spread of a highly drug-resistant cholera strain from Yemen down through Africa. The study was published in the New England Journal of Medicine.

Cholera is caused by the bacteria Vibrio cholerae and in its most severe forms, it is one of the most rapidly fatal infectious diseases: in the absence of treatment, patients can die within hours. Treatment primarily involves replacing lost water and electrolytes, but antibiotics are also used in addition to rehydration therapy. They are essential in reducing the duration of infection and breaking chains of transmission as quickly as possible.

A strain resistant to ten antibiotics – including azithromycin and ciprofloxacin, two of the three recommended for treating cholera – was identified for the first time in Yemen during the cholera outbreak in 2018-2019[1].

Scientists have now been able to trace the spread of this strain by studying the bacterial genomes. After Yemen, it was identified again in Lebanon in 2022[2], then in Kenya in 2023, and finally in Tanzania and the Comoros Islands – including Mayotte, a French département off the south-east coast of Africa – in 2024. Between March and July 2024, the island of Mayotte was affected by an outbreak of 221 cases caused by this highly drug-resistant strain.

“This study demonstrates the need to strengthen global surveillance of the cholera agent, and especially to determine how it reacts to antibiotics in real time. If the new strain that is currently circulating acquires additional resistance to tetracycline, this would compromise all possible oral antibiotic treatment,” concludes Professor François-Xavier Weill, Head of the Vibrios CNR at the Institut Pasteur and lead author of the study.

[1] Press release 19/08/2023 – Genes fuelling antibiotic resistance in Yemen cholera outbreak uncovered

[2] https://www.nature.com/articles/s41467-024-51428-0

Source: Institut Pasteur

Categories : Mental HealthTags : Leave a comment

Job Strain Compromises Sleep Quality Years Later

On By ModernMedia
Photo by Andrea Piacquadio

In a recent study published in the American Journal of Industrial Medicine, middle aged workers in the US who reported high job strain at the start of the study experienced significantly more sleep disturbances over an average follow-up of nine years.

The study analysed data from 1721 workers, with an average age of 51 years, who participated in the Midlife in the United States (MIDUS) study. Sleep disturbances were assessed with an established scale, based on four sleep-related symptoms: trouble falling asleep, waking up during the night and having difficulty going back to sleep, waking up too early in the morning and being unable to get back to sleep, and feeling unrested during the day no matter how many hours of sleep.

The team used six different formulations to quantify job strain based on Karasek’s Job‐Demand‐Control model, which defines job strain as a combination of high job demand and low job control. All formulations showed significant associations between higher job strain at baseline and increased sleep disturbances over time.

“Our findings also suggest that the continuous formulations of job strain demonstrate better model performance with consistent and robust results, offering empirical evidence for future psychosocial occupational health research in the United States,” said the first author Yijia Sun, an MS candidate at the University of California, Los Angeles.

Corresponding author Jian Li, MD, PhD, a professor of Work and Health at the University of California, Los Angeles, noted that there is an urgent need for workplace interventions to reduce stress. “Strategies such as redesigning workloads and promoting worker autonomy could play an important role in improving sleep health and workers’ well-being,” he said.

Source: Wiley

Categories : Neurodegenerative DiseasesTags : Leave a comment

Herpes Virus Might Drive Alzheimer’s Pathology, Study Suggests

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Neurons in the brain of an Alzheimer’s patient, with plaques caused by tau proteins. Credit: NIH

University of Pittsburgh researchers uncovered a surprising link between Alzheimer’s disease and herpes simplex virus-1 (HSV-1), suggesting that viral infections may play a role in the disease. The study results were published in Cell Reports.

The study also revealed how tau protein, often viewed as harmful in Alzheimer’s, might initially protect the brain from the virus but contribute to brain damage later. These findings could lead to new treatments targeting infections and the brain’s immune response.

“Our study challenges the conventional view of tau as solely harmful, showing that it may initially act as part of the brain’s immune defence,” said senior author Or Shemesh, assistant professor in the Department of Ophthalmology at Pitt. “These findings emphasise the complex interplay between infections, immune responses and neurodegeneration, offering a fresh perspective and potential new targets for therapeutic development.”

The scientists identified forms of HSV-1-related proteins in Alzheimer’s brain samples, with greater amounts of viral proteins co-localised with tangles of phosphorylated tau—one of the hallmarks of Alzheimer’s pathology—in brain regions especially vulnerable to Alzheimer’s across disease stages.

Further studies on miniature models of human brains in a Petri dish suggested that HSV-1 infection could modulate levels of brain tau protein and regulate its function, a protective mechanism that seemed to decrease post-infection death of human neurons.

While the precise mechanisms by which HSV-1 influences tau protein and contributes to Alzheimer’s disease are still unknown, Shemesh and his colleagues plan to explore those questions in future research. They aim to test potential therapeutic strategies that target viral proteins or fine-tune the brain’s immune response and investigate whether similar mechanisms are involved in other neurodegenerative diseases, such as Parkinson’s disease and amyotrophic lateral sclerosis.

Source: University of Pittsburgh