Neurons that regulate mouse torpor.

The advent of endothermy, which is achieved through the continuous homeostatic regulation of body temperature and metabolism1,2, is a defining feature of mammalian and avian evolution. However, when challenged by food deprivation or harsh environmental conditions, many mammalian species initiate adaptive energy-conserving survival strategies-including torpor and hibernation-during which their body temperature decreases far below its homeostatic set-point3-5. How homeothermic mammals initiate and regulate these hypothermic states remains largely unknown. Here we show that entry into mouse torpor, a fasting-induced state with a greatly decreased metabolic rate and a body temperature as low as 20 °C6, is regulated by neurons in the medial and lateral preoptic area of the hypothalamus. We show that restimulation of neurons that were activated during a previous bout of torpor is sufficient to initiate the key features of torpor, even in mice that are not calorically restricted. Among these neurons we identify a population of glutamatergic Adcyap1-positive cells, the activity of which accurately determines when mice naturally initiate and exit torpor, and the inhibition of which disrupts the natural process of torpor entry, maintenance and arousal. Taken together, our results reveal a specific neuronal population in the mouse hypothalamus that serves as a core regulator of torpor. This work forms a basis for the future exploration of mechanisms and circuitry that regulate extreme hypothermic and hypometabolic states, and enables genetic access to monitor, initiate, manipulate and study these ancient adaptations of homeotherm biology.

Health care-associated Clostridioides difficile infection: Learning the perspectives of health care workers to build successful strategies.

BACKGROUND: Clostridioides difficile (C difficile) is one of the most common health care-associated infections that negatively impact patient care and health care costs. This study takes a unique approach to C difficile infection (CDI) control by investigating key prevention obstacles through the perspectives of Stanford health care (SHC) frontline health care personnel. METHODS: An anonymous qualitative survey was distributed at SHC, focusing on knowledge and practice of CDI prevention guidelines, as well as education, communication, and perspectives regarding CDI at SHC. RESULTS: 112 survey responses were analyzed. Our findings unveiled gaps in personnel's knowledge of C difficile diagnostic guidelines and revealed a need for targeted communication and guideline-focused education. Health care staff shared preferences and recommendations, with the majority recommending enhanced communication of guidelines and information as a strategy for reducing CDI rates. The findings were then used to design and propose internal recommendations for SHC to mitigate the gaps found. DISCUSSION: Many guidelines and improvement strategies are based on strong scientific and medical foundations; however, it is important to ask whether these guidelines are effectively translated into practice. Frontline health care workers hold empirical perspectives that could be key in infection control. CONCLUSIONS: Our findings emphasize the importance of including frontline health care personnel in infection prevention decision-making processes and the strategies presented here can be applied to mitigating infections in different health care settings.

Single-Lesion Skin Cancer Risk Stratification Triage Pathway.

Importance: Access to timely dermatologic care remains a challenge, especially for patients with new skin lesions. Assessing the efficiency of new triage pathways may assist in better resource allocation and shorter time to care. Objective: To evaluate whether a rule-based triage system was associated with better skin cancer risk stratification of patients and reduced wait times. Design, Setting, and Participants: This retrospective quality improvement cohort study of patients referred to Stanford University dermatology clinics was conducted between November 2017 and January 2023. A rules-based triage system based on a priori-determined high-risk lesion characteristics was implemented. Exposures: Referral reasons and risk factors of patients provided by their primary care physicians. Main Outcomes and Measures: Biopsy results of patients (diagnosis of any skin cancer and melanoma) at their visit or within 6 months after the visit. Regression models were used to assess the association between risk factors at referral and (1) biopsy outcomes and (2) time to first visit, adjusting for sociodemographic factors. Results: Among 37 478 patients (mean [SD] age, 54 (18) years; 21 292 women [57%]), the rates of aggregate biopsy, malignant biopsy specimens, and melanoma were comparable across patients seen after (n = 12 302) and before (n = 25 176) the implementation of the new triage pathway. Patients seen through the lesion pathway had a higher risk of having malignant biopsy results (adjusted risk ratio [aRR], 1.6; 95% CI, 1.4-1.9) and melanoma (aRR, 2.0; 95% CI, 1.2-3.2) than those not seen through the pathway. Lesions that were concerning to referring clinicians for skin cancer were associated with an increased risk of skin cancer (all skin cancer: aRR, 2.8; 95% CI, 2.2-3.5; melanoma: aRR, 2.02; 95% CI, 1.1-3.7). Patients in the 3 high-risk lesion groups were seen faster in the new triage pathway (mean reduction, 26 days; 95% CI, 18-34 days). Conclusions and Relevance: In this study, a new automated, rules-based referral pathway was implemented that expedited care for patients with high-risk skin cancer. This reform may have contributed to improving patient stratification, reducing the time from referral to first encounter, and maintaining accuracy in identifying malignant lesions. The findings highlight the potential to optimize clinical resource allocation by better risk stratification of referred patients.

A torpor-like state (TLS) in mice slows blood epigenetic aging and prolongs healthspan.

Torpor and hibernation are extreme physiological adaptations of homeotherms associated with pro-longevity effects. Yet the underlying mechanisms of how torpor affects aging, and whether hypothermic and hypometabolic states can be induced to slow aging and increase health span, remain unknown. We demonstrate that the activity of a spatially defined neuronal population in the avMLPA, which has previously been identified as a torpor-regulating brain region, is sufficient to induce a torpor like state (TLS) in mice. Prolonged induction of TLS slows epigenetic aging across multiple tissues and improves health span. We isolate the effects of decreased metabolic rate, long-term caloric restriction, and decreased core body temperature (Tb) on blood epigenetic aging and find that the pro-longevity effect of torpor-like states is mediated by decreased Tb. Taken together, our findings provide novel mechanistic insight into the pro-longevity effects of torpor and hibernation and support the growing body of evidence that Tb is an important mediator of aging processes.

Azure-winged magpies fail to understand the principle of mirror imaging.

Mirror self-recognition (MSR) is considered a crucial step in the emergence of self-cognition. The MSR paradigm has become a standard method for evaluating self-cognition in several species. For example, Eurasian magpies and Indian house crows have passed the mark test for self-cognition, whereas efforts to find MSR in other corvid species have failed. However, no literature has conducted MSR tests on azure-winged magpies, a species of corvids. Therefore, the current research aimed to investigate the MSR behaviours of azure-winged magpies upon looking into a mirror for the first time. The study included four tests: (1) mirror preference and standardised mirror exploration, (2) single vertical mirror test, (3) mark test and (4) mirror-triggered search test. The azure-winged magpies displayed immense curiosity towards the mirror and their images in the mirror in Test 1&2. In the subsequent mark tests, they failed to recognise themselves in the mirror and regarded their images as conspecifics. Behaviour analysis showed no significant difference between marked and unmarked behaviours. Finally they seemed to infer the presence of bait from the image in the mirror, but were found to fail to understand that the location of the bait in the mirror was the same as that in the real world. For a better insight into the MSR behaviour of azure-winged magpies, research studies involving prolonged mirror exposure and training are recommended.

Elevated Risk of Visceral Malignant Neoplasms in Extramammary Paget Disease.

This cross-sectional study evaluates the incidence and types of cancers that develop years after an extramammary Paget disease (EMPD) diagnosis.