Can Alzheimer's disease be contagious? Five cases of medical transmission have been reported | Science and Technology Weekly

Compiled by Zhou Shuyi

Can Alzheimer's disease be contagious? Five cases of medical transmission have been reported

Alzheimer's disease (AD) is a chronic, progressive neurodegenerative disease of unknown etiology and is the main subtype of senile dementia. A study published in Nature Medicine on January 29 showed that five children who had received cadaveric human pituitary growth hormone (c-hGH) treatment as children had early-onset progressive cognitive impairment that met the diagnostic criteria for Alzheimer's disease, suggesting that Alzheimer's disease may be transmitted through medical transmission.

Between 1959 and 1985, at least 1,848 patients in the UK received c-hGH treatment, of which 80 patients developed fatal Creutzfeldt-Jakob disease due to prion contamination of c-hGH. This treatment has caused more than 200 cases of nosocomial Creutzfeldt-Jakob disease worldwide and was subsequently stopped by many countries. Previous studies have shown that some c-hGH samples are also contaminated with beta-amyloid protein, and in some cases of Creutzfeldt-Jakob disease caused by c-hGH treatment, the pathological characteristics of beta-amyloid protein have also been detected.

One of the patients showed relevant pathological features on brain imaging. | Source: John Collinge et al.

The researchers investigated eight British people who had been treated with c-hGH as children. They did not suffer from Creutzfeldt-Jakob disease, but five of them showed symptoms consistent with early-onset dementia (symptoms appear between the ages of 38 and 55), which met the diagnostic criteria for Alzheimer's disease. Genetic testing ruled out the possibility of genetic factors causing the disease, and further testing showed that the patients' brains had deposits of beta-amyloid protein, a biomarker characteristic of Alzheimer's disease. Mouse experiments showed that misfolded beta-amyloid protein has prion-like infectivity and can be used as a "seed" to induce related pathology in the living brain. The study believes that c-hGH is contaminated with beta-amyloid protein, triggering a long-term pathogenic cascade reaction, which ultimately leads to Alzheimer's disease. Experts emphasize that the transmission route discovered in the study is very rare, and there is currently no evidence that AD can be transmitted through daily contact. More caution should be exercised when preparing surgical instruments, handling tissues, and using therapeutic biologics (especially human-derived biologics). The new study also helps to understand the early occurrence mechanism of AD and provide corresponding prevention strategies.

Paper link:

https://www.nature.com/articles/s41591-023-02729-2

Musk announces Neuralink completes first human brain chip implant

On January 30, American entrepreneur Elon Musk announced on social media X that his brain-computer interface company Neuralink carried out the first human transplant of a brain-computer interface device on the 29th, and the subject is currently recovering well; preliminary results show that the detection of neuronal activity signals is "very promising."

Telepathy | Source: Neuralink

Musk said in a follow-up tweet that the first implant is called "Telepathy", "You can control your phone or computer just by thinking, and control almost any device through them. The initial users will be those who have lost the use of their limbs." The transplant surgery requires opening the subject's skull, and then the surgical robot will implant the implant into the brain area. Telepathy records neural activity through 1024 electrodes distributed on 64 silk threads, and after chip processing, it is wirelessly transmitted to a dedicated application, which can decode the data stream into actions and intentions. The diameter of the implanted microneedle is only 10 to 12 microns, slightly larger than the diameter of a red blood cell, to reduce damage to the cerebral cortex.

Founded in 2016, Neuralink focuses on the research and development of implantable brain-computer interface devices. The company said that after being implanted in the brain, the device can read neural activity signals and is expected to be used to treat cervical spinal cord injuries, amyotrophic lateral sclerosis and other neurological diseases, helping paralyzed people restore the ability to communicate with the outside world and even walk again. Last May, Neuralink obtained approval from the US FDA to start human clinical trials of brain implant devices. In September of the same year, the company began recruiting volunteers for clinical trials. Reuters reported in December 2022 that Neuralink's animal experiments resulted in the deaths of about 1,500 animals, including sheep, pigs and monkeys. In July 2023, the head of the U.S. Department of Agriculture said that the company had not been found to have violated any animal research regulations. (Neuralink, Reuters)

The frog kicks its legs upwards to scare off its competitors

For most male frogs, croaking is a way to intimidate potential rivals, saying "don't touch my girlfriend." But when rushing streams and waterfalls drown out these warnings, they have to find other ways. At the annual meeting of the Society for Integrative and Comparative Biology held recently, researchers introduced that more than 40 species of frogs living in noisy environments will extend their hind legs upward to warn competitors.

The researchers speculate that this kicking action is likely to imitate the behavior of predators. In the eyes of frogs, most prey grows horizontally (such as worms), while predators attack from the vertical direction (such as humans reaching out to grab them). Therefore, frogs tend to attack horizontal objects and avoid vertical objects.

In many vertebrates, high levels of testosterone are associated with more aggressive territorial behavior. For example, toads with higher testosterone levels tend to call louder. To test the hypothesis, researchers injected testosterone into the abdomen of Bornean rock frogs (Staurois parvus), and the frogs lifted their hind legs higher and straighter. This shows that "pushing up" is closely related to territorial behavior.

However, not all competitors are scared away by this trick. The researchers showed the frogs rectangular strips in different directions on the screen to test their reactions. The results showed that all frogs would try to attack the horizontal strips. Frogs that could not "kick their legs upwards" would freeze or move away from the vertical strips, as if threatened; and those frogs that learned to kick their legs had different reactions: some frogs froze, while others would indiscriminately attack the vertical strips. The researchers pointed out that during the confrontation, some male frogs had obviously tasted the sweetness and realized that the other party was just bluffing.

And as more male frogs ignore such warnings, the intimidation tactics are becoming more and more outrageous: Some frogs lift their legs higher, while others choose to kick out both legs at the same time. (Science News)

Japan's lunar probe briefly awakens before returning to sleep

On January 19, Beijing time, the small lunar probe SLIM launched by the Japan Aerospace Exploration Agency (JAXA) successfully landed on the lunar surface. However, due to an abnormality in the propulsion system, the probe was in an "upside-down" position after landing, and the solar panels could not receive enough sunlight. The system entered a dormant state through ground commands on the 20th. Due to the constant changes in the direction of sunlight shining on the lunar surface, the probe "woke up" on the evening of the 28th, resumed power generation and established a communication connection with the ground.

On February 1, JAXA announced that after a brief awakening, SLIM entered a dormant state again because the landing site ushered in the "sunset" and could not use solar power generation. It is expected to try to restart work in mid-to-late February when the solar panels receive sunlight. It is reported that the team sent a power-on command to the probe on the evening of January 31, but the probe did not respond, thus confirming that it had entered a dormant state.

The last photo taken by SLIM before nightfall. | Source: JAXA

It is reported that SLIM needs to survive the long night of 14.5 Earth days, and welcome the suitable light and temperature conditions around February 15, and then it can start working again. During this period, the temperature on the lunar surface will drop to about minus 170 degrees Celsius. SLIM was not designed to take into account the harsh environment of the lunar surface at night. In such cold conditions, many electronic devices may be damaged, and it is still unknown whether the probe can be "wake up" at that time. (JAXA)

Harvard Medical School professor accused of academic misconduct

On February 1, Elisabeth Bik, a well-known academic fraud fighter, published a blog post on the Science Integrity Digest website, revealing that 28 papers under the name of Khalid Shah, deputy director of neurosurgery research at Brigham and Women's Hospital, professor at Harvard Medical School, and top neuroscientist, were suspected of academic misconduct, including falsified data, image tampering, and plagiarism.

On the left is the PLOS ONE paper published by Elrod et al. of Emory University School of Medicine in 2010, showing head and neck squamous cell carcinoma tissue; on the right is Shah's 2022 Nat. Commun. paper, showing glioblastoma tissue. Matching images are marked with red and green boxes respectively. | Image source: Elisabeth Bik

Bick said in the blog post that these papers were published between 2001 and 2023. One of the papers, entitled "Target receptor identification and subsequent treatment of resected brain tumors with encapsulated and engineered allogeneic stem cells," was particularly problematic. The study was published in Nature Communications on May 19, 2022, and Shah was listed as the corresponding author. Through AI software comparison, Bick found that many pictures in the article were very similar to those in previous papers. Two pictures in Figure 1e and Figure 1f, and nine pictures in Supplementary Figure 4b matched pictures from other research teams, which were not related to the study. Bick pointed out that other papers were published earlier, with fewer images and higher resolution, indicating that they were the original source. Image searches showed that three pictures matched those provided by suppliers of laboratory consumables and reagents. The relevant person in charge confirmed that these pictures were produced internally by the company and Shah was not authorized to use them. In addition, there is a problem with image reuse in Supplementary Figure 5a, and the number of problematic pictures in the article totals 17. No similar situation was found in the remaining 27 articles, but image reuse problems also existed to varying degrees.

According to The Wall Street Journal, Shah declined to comment on the allegations. Paul Anderson, chief academic officer of Mass General Brigham, the health system that owns Brigham and Women's Hospital, said that any allegations of research integrity would be handled through a "robust and confidential process." Several journals, including Nature Communications, responded that they had received Bick's report and were reviewing it.

Shah is committed to developing new treatments for malignant brain tumors (glioblastoma) through stem cells and gene editing. Public information shows that he is the co-author of more than 100 papers in the fields of molecular biology and cancer, has founded two biotechnology companies, and holds more than 10 patents. His research funds mainly come from the National Cancer Institute of the National Institutes of Health, totaling millions of dollars.

Bick blog:
https://scienceintegritydigest.com/2024/02/01/problems-in-harvard-medical-school-studies-include-images-taken-from-other-researchers-papers-and-vendor-websites/#more-3509

Pregnancy dramatically changes organ metabolism

During pregnancy, pregnant women's bodies undergo a series of adaptive changes, such as heart remodeling and liver enlargement. However, the specific changes in tissue and organ metabolism at the molecular level are still unclear. In a study published in Cell on February 1, researchers constructed metabolome maps of 273 samples of 23 tissues and organs of crab-eating macaques (Macaca fascicularis) during the non-pregnant period and different periods of pregnancy, revealing the dynamic evolution of metabolic networks of various tissues and organs in crab-eating macaques during pregnancy, metabolic pathway adaptation, and key adaptive metabolites.

Non-human primates are highly similar to humans in terms of physiology, reproductive characteristics and gestational cycle, and are ideal animal models for studying the pregnancy adaptation of multiple tissues and organs in primate mothers. The researchers analyzed the non-targeted metabolome of 273 samples of 23 tissues and organs in crab-eating macaques during non-pregnancy, early pregnancy, mid-pregnancy and late pregnancy. The correlation analysis of metabolome data showed that compared with the non-pregnancy period, the metabolome correlation between the 23 tissues and organs decreased with the progress of pregnancy and reached a highly decoupled state in late pregnancy. The researchers identified 8 core metabolic pathways (including steroidogenesis, glutamate metabolism, tyrosine metabolism, purine metabolism, porphyrin metabolism, bile acid biosynthesis, pyrimidine metabolism and arachidonic acid metabolism) that were significantly changed in multiple tissues and organs during pregnancy. The difference fold analysis found that there were 91 differential metabolites shared by the 23 tissues and organs. The above studies show that primate mothers experience huge metabolic disturbances and challenges during pregnancy, and metabolic reprogramming occurs in multiple tissues and organs.

Paper link:
https://doi.org/10.1016/j.cell.2023.11.043

New type of solar radio emission discovered

A study recently published in The Astrophysical Journal has discovered a new type of solar radio burst that is significantly different from Type II and Type III radio bursts - solar solitary radiation. The new research is expected to provide a powerful new means of detecting the "meta-process" of magnetic plasma activity in the solar atmosphere on the particle dynamics scale.

Based on the observation data of the Parker Solar Probe (PSP) at about 1/6 AU from the sun, the researchers found that there are a large number of small-scale weak radio radiation sources in an open low-density magnetic channel. The duration of these small-scale radiation sources is on the order of minutes, and the radiation frequency varies from the order of 10 MHz to the order of 0.1 MHz. The radiation intensity is relatively weak and has decayed to the point where it is difficult to detect at 1 AU. Its dynamic spectrum shows the characteristics of strong evolution, and the relative frequency drift rate decreases from more than 1% per second at the high-frequency end to less than 1% per second at the low-frequency end. The researchers combined the solar atmospheric model to analyze the radiation mechanism and dynamic evolution behavior of this new type of radio burst. The results show that its radiation source area is mainly located in the high corona region of 1.1 to 6.1 solar radii, which belongs to the transition zone from the corona to the solar wind and is a typical solar wind acceleration zone. At the same time, the dynamic Alfvén solitary waves and the cyclotron maser radiation of the accelerated electrons captured in this area can self-consistently explain the radiation mechanism of this type of radio burst and the strong evolution behavior of its dynamic spectrum.

Paper link:

https://iopscience.iop.org/article/10.3847/1538-4357/ad0e65

This article is supported by the Science Popularization China Starry Sky Project

Produced by: China Association for Science and Technology Department of Science Popularization

Producer: China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.

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