Wild and feral cats appear to release more toxoplasmosis parasites in places densely populated with people, new research suggests. These cats also “shed” more when the temperature is warmer, a significant finding given climate change, according to the report published online June 21 in PLOS ONE. Policymakers could help protect humans from this illness by better managing these stray cat populations, the researchers said. “Changes from climate or human activities can affect disease transmission in ways that we don’t fully understand yet,” said study author Sophie Zhu, of the University of California, Davis, and colleagues. “In our study, we can see how these factors may be associated with changes in Toxoplasma shedding by cats, which in turn can affect the risk of exposure to vulnerable people and wildlife,” the researchers explained in a journal news release. Toxoplasmosis is a mild-to-severe disease that can be especially dangerous in pregnancy. It is caused by Toxoplasma gondii, which can affect humans and many wild and domestic animals. Cats, sheep, mice, birds and sea otters are among the vulnerable creatures. Humans can become infected when they accidentally come in contact with an infected cat’s feces. This can happen unknowingly while gardening, for example. While most T. gondii transmission is driven by domestic cats shedding the parasite at a stage of its life cycle known as oocyst, research has tended…  read on >  read on >

Living in a walkable neighborhood fosters socialization and helps create a strong sense of community, new research shows. Among the active behaviors these walkable neighborhoods promote are walking for leisure or as transportation to school, work shopping or home. “Our built environments create or deny long-lasting opportunities for socialization, physical activity, contact with nature and other experiences that affect public health,” said senior study author James Sallis, a professor at the Herbert Wertheim School of Public Health at the University of California, San Diego. “Transportation and land use policies across the U.S. have strongly prioritized car travel and suburban development, so millions of Americans live in neighborhoods where they must drive everywhere, usually alone, and have little or no chance to interact with their neighbors,” Sallis added in a university news release. Data came from the Neighborhood Quality of Life Study, which included 1,745 adults ages 20 to 66 living in 32 neighborhoods located in and around Seattle, Baltimore and Washington, D.C. In walkable neighborhoods, people can wave hello to a neighbor, ask for help or socialize in their homes, said study first author Jacob Carson, a student in the UC San Diego – San Diego State University Joint Doctoral Program in Public Health. Neighborhoods where driving is necessary may have the opposite effect, preventing neighbors from socializing. “Promoting social interaction is an important public…  read on >  read on >

It’s common knowledge that loss is a part of male aging — loss of hair, loss of muscle tone, loss of vision or hearing. But men growing older also start losing the very thing that makes them biological males, their Y chromosome, and that can leave them more vulnerable to cancer, a new study says. The loss of the Y chromosome can help cancer cells evade detection by the body’s immune system, according to researchers from Cedars-Sinai Medical Center, in Los Angeles. Specifically, it results in more aggressive bladder cancer among men, the study authors reported June 21 in the journal Nature. “This study for the first time makes a connection that has never been made before between loss of the Y chromosome and the immune system’s response to cancer,” said researcher Dr. Dan Theodorescu, director of Cedars-Sinai Cancer. “We discovered that loss of the Y chromosome allows bladder cancer cells to elude the immune system and grow very aggressively,” Theodorescu said in a medical center news release. It’s not all bad news, however. Bladder cancers driven by the loss of the Y chromosome also were more vulnerable to immune checkpoint inhibitors, which are drugs that enhance the body’s ability to target and destroy tumor cells, the researchers explained. Each human cell normally has one pair of sex chromosomes. Men’s cells have one X and…  read on >  read on >

New research on horses and dogs found elevated levels of PFAS “forever chemicals,” establishing horses as sentinel species. Sentinel species provide advance warning of a danger to people. The work also advanced knowledge about PFAS exposure and liver and kidney function in these animals. PFAS stands for per-and polyfluoroalkyl substances, a group of chemicals used in plastics and grease- and water-resistant materials. They’re a health concern because they don’t break down in the environment and are found in soil and water sources. “Horses have not previously been used to monitor PFAS exposure,” said first author Kylie Rock, a postdoctoral researcher at North Carolina State University. “But they may provide critical information about routes of exposure from the outdoor environment when they reside in close proximity to known contamination sources.” In the new study, researchers detected elevated PFAS levels in the blood of 31 pet dogs and 32 horses from Grays Creek, N.C., including dogs that drank only bottled water. The study was conducted at the request of residents concerned about their pets’ well-being. Their homes used wells that state inspectors had determined to contain PFAS. Animals each had a general veterinary health check, as well as blood tests to screen for 33 PFAS chemicals. The chemicals were chosen based on compounds present in the Cape Fear River basin and the availability of standards to analyze…  read on >  read on >