Scientists

Stem cell transplants in cancer patients have achieved complete remission of HIV in a few cases in people who are also HIV-positive. However, in most cases, the donors were homozygous—with two identical copies of the gene—for a mutation in the CCR5 gene that is considered protective against the virus. A German team has now reported a new case of remission in a 60-year-old man with leukemia—called the “second Berlin patient”—in which the donor was heterozygous (only one of the two copies contained the mutation), which could broaden the alternatives. The results are published in the journal Nature.

The veterinary services of the Catalan Regional Government have notified the Ministry of Agriculture, Fisheries, and Food of the detection of two wild boars positive for African swine fever virus in Bellaterra (Barcelona), where they were found dead on November 26. These cases represent the first detection of the disease in Spain since November 1994, according to the ministry in a press release. African swine fever is considered a Category A disease by the European Union, which means that member states must take measures to control and eradicate it as soon as possible. It is a non-zoonotic disease, meaning that humans are not susceptible to infection either through contact with animals or through the consumption of animal products.

Global vaccination efforts have achieved an 88% reduction in measles deaths between 2000 and 2024, and nearly 59 million lives have been saved by the vaccine since the beginning of the century, according to a new report from the World Health Organization (WHO). However, an estimated 95,000 people—mostly children under the age of five—died from measles in 2024, a disease that could be prevented with an effective, low-cost vaccine. Although the death toll is one of the lowest in this period, measles cases are on the rise worldwide, with an estimated 11 million infections in 2024, nearly 800,000 more than pre-pandemic levels in 2019. Specifically, cases in Europe increased by 47% between 2019 and 2024.

Gilberto and Tomás are two macaques trained to synchronise their movements with the rhythm of a metronome, who were also able to tap to a musical beat, according to a study published in Science. This result contradicts the vocal learning hypothesis, according to which only species capable of complex vocalisations can perceive and follow a musical rhythm.

A US research team has devised a method that uses a browser extension to alter the algorithm of X (formerly Twitter) to study its impact on user behaviour. In a 10-day experiment with 1,256 volunteers during the 2024 US presidential campaign, they used the method to vary the content expressing anti-democratic attitudes and partisan hostility. According to the authors, the results—published in Science—provide causal evidence that greater or lesser exposure to this type of content alters polarisation in the same way. Their conclusions contradict previous research published in the same journal, which found no such relationship on Facebook or Instagram. In that case, the study was conducted in collaboration with and funded by Meta.

Viruses that cause avian influenza are capable of replicating at temperatures higher than a typical fever, according to a study in in vitro models and mice. ‘Fever-resistant replication could help explain why avian viruses and pandemic influenza viruses with avian PB1 cause more severe disease in humans,’ the authors write in the journal Science.

A study published in Scientific Reports concludes that adults who use Instagram very frequently overestimate their ‘addictive’ use, which complicates self-control and increases feelings of guilt. According to the research, excessive use, in most cases, is not an addiction but a habit. The study was conducted on more than 1,000 Americans and suggests that the fact that many think they have an ‘addiction’ may be related to the media's frequent use of this term when talking about social media. 

An artificial intelligence (AI) model trained on over 400,000 mammograms and analyzed in a separate sample of over 240,000 improved cancer risk prediction in cases of dense breasts, which are more common in young women or those with a low body mass index. This is an important factor in screening, especially because it can hinder tumor detection. The results are presented as an abstract, not yet peer-reviewed, at the annual meeting of the Radiological Society of North America.

Consuming up to four cups of coffee a day is associated with an increase in telomere length in people with severe mental disorders, such as schizophrenia or bipolar disorder. Telomere length is an indicator of cellular ageing and is shorter in people with these disorders, although the causes are not clearly understood. According to the study, published in BMJ Mental Health, the effect shown is comparable to ‘a biological age five years younger’ in coffee drinkers. 

A century ago, astronomer Fritz Zwicky observed that galaxies were moving faster than their mass should allow, leading him to infer the presence of an invisible structure, dark matter. Since the particles that make up dark matter do not interact with electromagnetic force, they cannot be observed directly, as they do not absorb, reflect, or emit light. Now, NASA's Fermi space telescope has found specific gamma rays in the center of the Milky Way that are consistent with the decay of theoretical dark matter particles, although they could also come from other sources. “If this is correct, to my knowledge, it would be the first time that humanity has ‘seen’ dark matter,” said study author Tomonori Totani in a press release. The article is published in the Journal of Cosmology and Astroparticle Physics.