Your deep sleep builds muscle and the US death rate just set a record low

The circuit lives in the hypothalamus and involves three distinct neuron types: growth hormone-releasing hormone neurons, plus two varieties of somatostatin neurons that act as a brake. Once growth hormone is secreted, it activates neurons in the locus coeruleus, a brainstem region tied to alertness, which then loops back and quiets the GHRH neurons, forming a feedback cycle that prevents the system from running unchecked [9]. The team, led by postdoctoral researcher Xinlu Ding, recorded actual neural activity in sleeping mice rather than simply drawing blood to check hormone levels afterward. That direct observation approach is what let them trace the circuit with precision. Growth hormone governs muscle repair, bone growth, fat metabolism, and glucose regulation, which is why athletes and teenagers need so much sleep and why poor sleep raises the risk of obesity, diabetes, and cardiovascular disease [9].

These cells, which resemble young neurons that never fully developed, were found in people over 80, still present despite decades of Alzheimer's pathology accumulating around them. In brains that had succumbed to the disease, these immature neurons were largely gone. The team developed new analytical methods for human tissue rather than relying on assumptions from animal studies, which had confused this field for years [6].

The biggest driver was the collapse in drug overdose deaths. Deaths from synthetic opioids, overwhelmingly fentanyl, had risen 23-fold between 2013 and 2023, from 3,105 to 72,776. By 2025, that number had fallen to roughly 70,000, a drop of nearly 40 percent in two years. Researchers credit a combination of wider naloxone distribution, shifts in the illicit fentanyl supply, and the grim arithmetic of a shrinking high-risk population. Deaths from Covid continued to fall, and earlier gains against heart disease and cancer held [43].

The procedure works by first flushing out the patient's existing immune cells with chemotherapy, then rebuilding the immune system from scratch using cells from a healthy donor. If the donor's cells don't carry the same faulty instructions, the rebuilt immune system simply never develops the attack [15]. Over 15 and 16 years of follow-up, neither patient has relapsed. The rogue antibodies that caused the disease have permanently disappeared. The male patient fathered two children and returned to normal life. The female patient, who had more severe neurological damage going in, regained partial use of her arms and takes no medication. The researchers note this is the longest follow-up of this treatment for NMO ever published [15].

Earlier estimates had put it at roughly five times Earth's mass, which raised the possibility it was a mini gas giant with crushing atmospheric pressure. The new measurement, published June 30 in The Astrophysical Journal and led by Paul Robertson at UC Irvine, puts it at only 2.3 times Earth's mass [13]. That smaller mass makes it almost certainly rocky, like Earth, rather than gaseous. The planet completes a full orbit every 21.5 days, but the red dwarf it circles emits 90 percent less radiation than the sun, placing GJ 3378b squarely in its star system's habitable zone, where liquid water could exist on the surface [13].

The app, called TACTICAS and co-designed with patients, analyzed pitch, number of pauses, and voice quality, then compared the data to daily symptom questionnaires [90]. Voice quality degraded measurably at the very start of a flare-up, before the person noticed their breathing worsening. When airways begin to constrict, less air passes over the vocal folds, making the voice breathier and rougher. The researchers found these acoustic changes could appear as early as three days before a full exacerbation [90].

The city was originally built around a network of interconnected lakes and canals, the Rajakaluve system, designed under the founder Kempegowda to channel stormwater between storage tanks that would hold it through the dry season. By the 20th century, the canals had been built over and used as open sewage drains [95]. The MOD Foundation and city partners recently restored the K100 Rajakaluve, one canal in the Koramangala Valley, from a toxic drain into a functioning green waterway. The project reduced local flooding, restored water flow between tanks, and created a corridor that now supports fish, birds, and community use. The World Bank has taken notice [95].