Medical Bulletin 20/April/2023

Here are the top medical news for the day:

Risk or benefit of removing ovaries at benign hysterectomy

Removal of the ovaries decreases the risk for ovarian cancer and greatly benefits the survival of women at high risk for ovarian cancer. However, not enough is known about how removal of the ovaries affects other possible outcomes, such as heart attack, stroke, other types of cancer, and how long patients live.

An emulated target trial of more than 140,000 women in Denmark found that removing the ovaries at benign hysterectomy was associated with increased risk for cardiovascular disease in younger women and cancer in older women at low risk for ovarian cancer. These findings support current recommendations for preserving ovaries in premenopausal patients. The findings are published in Annals of Internal Medicine.

Reference:

Annals of Internal Medicine.,DOI 10.7326/M22-1628

Amubarvimab/romlusevimab reduces hospitalization and death by 79% in adults diagnosed with COVID-19: Study

As COVID-19 evolves, the development of safe and effective therapeutics is a high priority. Amubarvimab and romlusevimab are non-competing anti-SARS-CoV-2 monoclonal antibodies with an extended half-life that may be an effective and safe option for persons who are at high risk of clinical progression to severe COVID-19.

A randomized controlled trial of more than 800 adults diagnosed with COVID-19 found that combination therapy with amubarvimab plus romlusevimab significantly reduced the rates of hospitalization and death compared to placebo. The clinical benefit was similar regardless of whether therapy was given within 5 days or more than 5 days of symptom onset. The findings are published in Annals of Internal Medicine.

Reference:

Teresa H. Evering, Kara W. Chew, Mark J. Giganti, et al; ACTIV-2/A5401 Study Team. Safety and Efficacy of Combination SARS-CoV-2 Neutralizing Monoclonal Antibodies Amubarvimab Plus Romlusevimab in Nonhospitalized Patients With COVID-19. Ann Intern Med. [Epub 18 April 2023]. doi:10.7326/M22-3428

Resident T-cells crucial in salmonella immunity: Study

When a pathogen enters the body, the immune system mounts a response, including CD4 T-cells which support other responses, such as antibody production by B-cells. When the infection is over, some of the cells specific to that pathogen remain as memory cells, waiting to be called rapidly into service again if the same threat returns.

Salmonella infections cause about a million deaths a year worldwide, and there is an urgent need for better vaccines for both typhoid fever and non-typhoidal Salmonella disease. New work from researchers at the UC Davis School of Veterinary Medicine shows how memory T cells, crucial for a vaccine that induces a powerful immune response, can be recruited into the liver in a mouse model of Salmonella.

Reference:

Professor Stephen McSorley et al,Optimal generation of hepatic tissue-resident memory CD4 T cells requires IL-1 and IL-2,Proceedings of the National Academy of Sciences,DOI 10.1073/pnas.221469912

“Stuck” stem cells linked with hair graying: Study

A new study shows certain stem cells to have a unique ability to move between growth compartments in hair follicles, but get stuck as people age and so lose their ability to mature and maintain hair color.

Led by researchers from NYU Grossman School of Medicine, the new work focused on cells in the skin of mice and also found in humans called melanocyte stem cells, or McSCs. Hair color is controlled by whether nonfunctional but continually multiplying pools of McSCs within hair follicles get the signal to become mature cells that make the protein pigments responsible for color.

Reference:

De-differentiation maintains melanocyte stem cells in a dynamic niche”,Nature,doi 10.1038/s41586-023-05960-6