In a groundbreaking study, researchers have captured real-time "molecular movies" showing how an enzyme changes shape during catalysis. Using an advanced technique called mix-and-inject serial crystallography at Japan's SACLA X-ray free-electron laser facility, the team observed domain movements and structural changes in the enzyme, copper amine oxidase enzyme over millisecond timescales, revealing dynamics that are nearly impossible to observe by other methods.

Kyoto, Japan -- Colorectal cancer, or CRC, is the world's second most lethal cancer based on the number of deaths, and is the third most prevalent malignant tumor. Doctors and patients have long been hoping for better diagnostics for prognosis, such as molecular subtyping, which uses data collected from cancer stem cells, or tumor-initiating cells, to further divide one type of cancer into subgroups. It may correlate with patient outcomes and enable better prognoses.

Though many CRC tissue samples have been analyzed and classified based on mRNA gene expression, currently the practical application of these studies in patient prognosis is limited for colorectal cancer. This motivated a team of researchers from Kyoto University to examine cancer stem cells for the molecular subtyping of CRC.

"We need more comprehensive and clinically useful markers and their signatures to help predict the outcome of each patient," says first author Fumihiko Kakizaki.

Kyoto, Japan -- Superconductors are materials that can conduct electricity with zero resistance, usually only at very low temperatures. Most superconductors behave according to well-established rules, but strontium ruthenate, Sr₂RuO₄, has defied clear understanding since its superconducting properties were discovered in 1994. It is considered one of the cleanest and best-studied unconventional superconductors, yet scientists still debate the precise structure and symmetry of the electron pairing that gives rise to its remarkable properties.

One powerful way to identify the underlying superconducting state is to measure how the superconducting transition temperature, or T_c, changes under strain, since different superconducting states respond differently when a crystal is stretched, compressed, or twisted. Many earlier experiments, especially ultrasound studies, suggested that Sr₂RuO₄ might host a two-component superconducting state, a more complex form of superconductivity that can support exotic behaviors such as internal magnetic fields or multiple coexisting superconducting domains. But a genuine two-component state is expected to respond strongly to shear strain.

This inspired a team of researchers from Kyoto University to use strain to understand the true nature of the superconducting state of Sr₂RuO₄. The researchers developed a technique that allowed them to apply three distinct kinds of shear strain to extremely thin Sr₂RuO₄ crystals. Shear strain is a type of distortion that shifts part of the crystal sideways, similar to sliding the top of a deck of cards relative to the bottom. The strain levels were carefully measured using high-resolution optical imaging down to 30 degrees K (−243 degrees C). The key discovery: the superconducting temperature hardly changed at all. Any shift in T_c was smaller than 10 millikelvin per percent strain, effectively below the detection limit.

Exogenous ochronosis is a rare but serious skin condition characterized by bluish-black pigmentation, linked to long-term hydroquinone use for treating hyperpigmentation. It was previously believed to stem from inhibition of homogentisate dioxygenase, an enzyme absent in human skin. A new international study reveals that instead, hydroquinone is metabolized by tyrosinase into reactive compounds that accumulate in the dermis, causing ochronosis. This insight highlights the need for safer, true tyrosinase inhibitors in treatment.