U.S. researchers have found through mouse experiments that gastrointestinal viruses such as norovirus and rotavirus may be transmitted through saliva, a previously unknown route of transmission for these viruses. In the past, gastrointestinal viruses that can cause stomach pain, vomiting, and diarrhea were generally thought to be transmitted by fecal-oral transmission, and although enterovirus genomic RNA has been detected in the saliva of infected individuals, it is thought to be caused by intestinal pollutants. The researchers first inoculated mouse pups with murine norovirus or rotavirus, and a few days later the mothers of the mice also showed signs of infection. The researchers found genomic RNA from murine norovirus or rotavirus in the mammary glands of mouse mothers, indicating that mammary glands may be the site of replication of enteroviruses, suggesting that sucking milk from mouse pups may be a transmission route. In adult mice, some, but not all, strains of murine norovirus or rotavirus have been found to replicate in the salivary glands.
Why does bamboo grow so fast
Bamboo is one of the fastest growing plants in the world. For example, Moso bamboo can reach 114.5 cm per day at the fastest growth rate. After 8 years of continuous research, several research teams from China and the United States have clarified the cellular basis of the rapid growth of Phyllostachys pubescens and its potential physiological and molecular regulation mechanisms, and revealed the synergistic mechanism of environmental factors-genes-rapid growth of bamboo node length. The mystery of the rapid growth of bamboo has been solved. The researchers analyzed the moso bamboo groups in 17 main producing areas of moso bamboo in China, and found that the 18th internode from the bottom to the top of the bamboo stalk is a representative internode for the high growth of bamboo shoots. When Phyllostachys pubescens grows rapidly, there are as many as 40 internodes that grow at different degrees of elongation at the same time. In addition, the internode growth of Phyllostachys edulis is modular growth, and the growing internodes include the cell division zone (up to 2 cm), the cell elongation zone (up to 12 cm) and the secondary cell wall thickening zone. These growing internodes can grow as fast as 11.8 cm per day, producing about 570 million cells, and depositing a large amount of lignin and cellulose at the same time, far exceeding the growth of other plants.
New gene that predisposes women to Alzheimer’s disease discovered
Researchers have previously found that some genetic variants increase people’s risk of Alzheimer’s disease (AD). For people over 65, the most well-known is the APOEε4 allele. About 60% of European AD patients carry this gene variant, compared with only 26% of the general population. Recently, American researchers have discovered a new gene called MGMT, which increases the risk of AD in women. Epigenetically regulated gene expression of MGMT, which repairs DNA damage, is significantly associated with the development of hallmark AD proteins, amyloid-beta and tau proteins, especially in women. Next, the researchers will further investigate why MGMT has a greater effect on AD risk in women than in men.
