OBJECTIVE

To determine the prevalence of rectal colonization with carbapenem-resistant organisms (CRO) among PGH neonatal intensive care unit (NICU) patients.

A prospective single-center observational study conducted over a 1-month period included all NICU 3 and cohort area patients admitted on April 24, 2024. Rectal swabs were collected for multidrug-resistant organism (MDRO) screening and repeated weekly for 1 month while admitted. Swabs were inoculated on chromogenic media, and isolates were identified and tested for antimicrobial sensitivity by disk diffusion. Clinical characteristics and outcomes were collected for 30 days from initial MDRO screening. Descriptive statistics were used to summarize the data.

The point prevalence of CRO colonization was 37% (14 of 38) at initial screening. There were 14 incident colonizations, hence the 4-week period prevalence of CRO colonization was 72.5% (29 of 40). The patients were mostly very preterm, very low birth weight neonates, majority were tested within the first 2 weeks of life, and half were exposed to meropenem at initial screening. Nosocomial infection developed in 29% and 64%, and 30-day mortality rate was 8% and 21% among initially non-CRO-colonized and CRO-colonized patients respectively. Despite high CRO colonization, no culture-proven CRO infection was observed. Surveillance screening documented persistent CRO colonization in 37%, but no decolonization. Escherichia coli, Klebsiella spp. and Serratia spp. were the most common colonizers.

The high prevalence of rectal CRO colonization in the NICU emphasizes the burden of antimicrobial resistance, but despite the high CRO colonization, no CRO infection was documented from the limited sample and study period.

BACKGROUND AND OBJECTIVE

Antimicrobial resistance (AMR) is a leading global public health concern as it resulted in more difficult-to-treat infections and fatalities. In the Philippines, drug-resistant E. coli, including multidrug-resistant (MDR), extended-spectrum beta-lactamase (ESBL)-producing, carbapenemase-producing carbapenem-resistant (CP-CR) E. coli, have been isolated from common food animals, increasing the risk of cross-contamination between humans, animals, and the environment. However, there is a lack of data on the distribution of E. coli in chicken meat in public wet markets. This study aims to describe the AMR profile of E. coli in raw chicken meat from retail stalls in a selected wet market in Manila City.

This quantitative descriptive study characterized the AMR profile of E. coli isolated from 25 raw chicken meat samples from a wet market in Manila City. Antimicrobial susceptibility was determined through disk diffusion method against 23 antimicrobial agents in 16 antimicrobial classes. MDR E. coli were identified based on the resistance patterns. ESBL- and carbapenemase-producing capacities of the bacteria were tested through double disk synergy test and modified carbapenem inactivation method, respectively.

Twenty-four out of 25 (96%) chicken samples contained E. coli isolates. Of these, 23 (96%) were classified as MDR. High resistance rates were observed against ampicillin (92%), tetracycline (88%), trimethoprim-sulfamethoxazole (83%), chloramphenicol (79%), ampicillin-sulbactam (75%), amoxicillin-clavulanic acid (67%), fosfomycin (67%), and streptomycin (54%). The majority of the E. coli isolates were still susceptible to a wide range of selected antimicrobial agents, including carbapenems (100%), ceftriaxone (100%), cefepime (100%), cefuroxime (96%), cefotaxime (96%), ceftazidime (96%), piperacillin-tazobactam (96%), aztreonam (96%), cefoxitin (92%), and nitrofurantoin (83%), among others. Meanwhile, none of the 24 isolated E. coli samples were classified as ESBL- and CP-CR E. coli.

Among the 25 chicken samples, 24 E. coli colonies were isolated that exhibited 0% to 92% resistance rates against selected antimicrobial agents. Most isolates were classified as MDR, but none were considered ESBLand CP-CR E. coli. This study suggests that chickens in wet markets can potentially serve as reservoir hosts for drugresistance genes, which could transfer to other bacteria and contaminate humans, animals, and the environment within the food production and supply chain. These findings emphasize the need for AMR surveillance and strategies to combat AMR in the Philippines through the One Health approach.

The circadian clock plays a critical role in regulating various physiological processes, including gene expression, metabolic regulation, immune response, and the sleep-wake cycle in living organisms. Post-translational modifications (PTMs) are crucial regulatory mechanisms to maintain the precise oscillation of the circadian clock. By modulating the stability, activity, cell localization and protein-protein interactions of core clock proteins, PTMs enable these proteins to respond dynamically to environmental and intracellular changes, thereby sustaining the periodic oscillations of the circadian clock. Different types of PTMs exert their effects through distincting molecular mechanisms, collectively ensuring the proper function of the circadian system. This review systematically summarized several major types of PTMs, including phosphorylation, acetylation, ubiquitination, SUMOylation and oxidative modification, and overviewed their roles in regulating the core clock proteins and the associated pathways, with the goals of providing a theoretical foundation for the deeper understanding of clock mechanisms and the treatment of diseases associated with circadian disruption.
Protein Processing, Post-Translational/physiology* ; Circadian Rhythm/physiology* ; Humans ; Animals ; CLOCK Proteins/physiology* ; Circadian Clocks/physiology* ; Phosphorylation ; Acetylation ; Ubiquitination ; Sumoylation

Circadian rhythms are core regulatory mechanisms that evolved to align biological functions with the Earth's rotation. These rhythms are conserved across organisms from unicellular life to multicellular species and play essential roles in metabolism, immune responses, and sleep-wake cycle. Circadian disruptions are strongly associated with various diseases. Over the past decades, genetic studies in Drosophila and mice have identified key conserved clock genes and uncovered transcription-translation feedback loops governing circadian regulation. Additionally, rhythmic neurons in the brain integrate complex neural circuits to precisely regulate physiological and behavioral rhythms. This review highlights recent advances in understanding the neuronal circuit mechanisms of rhythmic neurons in the Drosophila brain and discusses future directions for translating circadian rhythm research into chronomedicine and precision therapies.
Animals ; Circadian Rhythm/genetics* ; Neurons/physiology* ; Drosophila/physiology* ; Brain/physiology* ; Nerve Net/physiology*

The circadian rhythm regulates the 24-hour physiological and behavioral cycles through endogenous molecular clocks governed by core clock genes via the transcription-translation feedback loop (TTFL). In mammals, the suprachiasmatic nucleus (SCN) serves as the central pacemaker, coordinating the timing of physiological processes throughout the body by regulating clock genes such as CLOCK, BMAL1, PER, and CRY. The molecular clocks of peripheral tissues and cells are synchronized by the SCN through TTFLs to regulate metabolism, immunity, and energy homeostasis. Numerous studies indicate that circadian rhythm disruption is closely related to obesity, type 2 diabetes, metabolic syndrome and other diseases, and the mechanism involves the dysregulation of glucose and lipid metabolism, abnormal insulin signaling and low-grade inflammation. In recent years, small-molecule compounds targeting the core clock components such as CRY, REV-ERB, and ROR have been identified and shown potential to modulate metabolic diseases by stabilizing or inhibiting the activity of key clock proteins. This review summarizes the mechanisms and advances in these compounds, and explores the challenges and future directions for their clinical translation, providing insights for chronotherapy-based metabolic disease interventions.
Humans ; Metabolic Diseases/physiopathology* ; Animals ; Circadian Rhythm/physiology* ; Biological Clocks/drug effects* ; CLOCK Proteins/physiology* ; Circadian Clocks/physiology* ; Suprachiasmatic Nucleus/physiology*

The circadian clock is an endogenous time-keeping system that maintains physiological homeostasis by integrating environmental and genetic interactions. Heart failure is a complex clinical syndrome characterized by structural abnormalities and/or functional impairment of the heart. Growing evidence suggests that core circadian components, such as BMAL1 and REV-ERBα, play important roles in modulating myocardial energy metabolism, inflammatory responses, and oxidative stress, contributing to myocardial structural and metabolic remodeling during heart failure progression. Notably, circadian disruption is closely associated with heart failure, with aberrant blood pressure rhythms and disturbances in the sleep-wake cycle in patients. The time-dependent efficacy of heart failure medications further supports the potential of chronotherapy-based strategies to improve clinical outcomes. Here, we summarize the multifaceted regulatory roles of the circadian clock, particularly core clock genes, in heart failure pathogenesis, providing a theoretical framework for developing personalized chronotherapeutic strategies for heart failure management.
Humans ; Heart Failure/physiopathology* ; Circadian Rhythm/physiology* ; Circadian Clocks/physiology* ; ARNTL Transcription Factors/physiology* ; Nuclear Receptor Subfamily 1, Group D, Member 1/physiology* ; Oxidative Stress ; Energy Metabolism ; Animals

Neurodevelopmental disorders (NDDs), including autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), and intellectual developmental disorder (IDD), are highly prevalent and lack effective treatments, posing significant health challenges. These disorders are frequently comorbid with disruptions in sleep rhythms, and sleep-related indicators are often used to assess disease severity and treatment efficacy. Recent evidence has highlighted the crucial roles of circadian rhythm disturbances and circadian clock gene mutations in the pathogenesis of NDDs. This review focuses on the mechanisms by which circadian rhythm disruptions and circadian clock gene mutations contribute to cognitive, behavioral, and emotional disorders associated with NDDs, particularly through the dysregulation of dopamine system. Additionally, we discussed the potential of targeting the circadian system as novel therapeutic strategies for the treatment of NDDs.
Humans ; Neurodevelopmental Disorders/genetics* ; Attention Deficit Disorder with Hyperactivity/genetics* ; Circadian Rhythm/genetics* ; Autism Spectrum Disorder/genetics* ; Mutation ; Intellectual Disability/genetics* ; Circadian Clocks/physiology* ; Dopamine/metabolism*

Major depressive disorder (MDD) affects people all over the world, and yet, its etiology is complex and remains incompletely understood. In this review, we aim to assess recent advances in understanding depression and its regulation, as well as its interaction with circadian rhythms. Circadian rhythms are internalized representations of the periodic daily light and dark cycles. Accumulating evidence has shown that MDD and the related mental disorders are associated with disrupted circadian rhythms. In particular, depression has often been linked to abnormalities in circadian rhythms because dysregulation of the circadian system increases susceptibility to MDD. The fact that several rhythms are disrupted in depressed patients suggests that these disruptions are not restricted to any one rhythm but rather involve the molecular circadian clock core machinery. The sleep-wake cycle is one rhythm that is often disrupted in depression, which often leads to disturbances in other rhythms. The circadian disruptions manifested in depressed patients and the effectiveness and fast action of chronobiologically based treatments highlight the circadian system as a key therapeutic target in the treatment of depression. This review assesses the evidence on rising depression rates and examines their contributing factors, including circadian misalignment. We discuss key hypotheses underlying depression pathogenesis, potential etiology, and relevant animal models, and underscore potential mechanisms driving depression's growing burden and how understanding these factors is critical for improving prevention and treatment strategies.
Humans ; Circadian Rhythm/physiology* ; Depressive Disorder, Major/therapy* ; Animals ; Sleep/physiology* ; Depression/therapy*

Recently, male reproductive health has attracted extensive attention, with the adverse effects of circadian disruption on male fertility gradually gaining recognition. However, the mechanism by which circadian disruption leads to damage to male reproductive system remains unclear. In this review, we first summarized the dual regulatory roles of circadian clock genes on the male reproductive system: (1) circadian regulation of testosterone synthesis via the hypothalamic-pituitary-testicular (HPT) and hypothalamic-pituitary-adrenal (HPA) axes; (2) non-circadian regulation of spermatogenesis. Next, we further listed the possible mechanisms by which circadian disruption impairs male fertility, including interference with the oscillatory function of the reproductive system, i.e., synchronization of the HPT axis, crosstalk between the HPT axis and the HPA axis, as well as direct damage to germ cells by disturbing the non-oscillatory function of the reproductive system. Future research using spatiotemporal omics, epigenomic assays, and neural circuit mapping in studying the male reproductive system may provide new clues to systematically unravel the mechanisms by which circadian disruption affects male reproductive system through circadian clock genes.
Male ; Humans ; Animals ; Circadian Clocks/physiology* ; Hypothalamo-Hypophyseal System/physiology* ; Circadian Rhythm/genetics* ; Spermatogenesis/physiology* ; Pituitary-Adrenal System/physiology* ; Testis/physiology* ; Testosterone/biosynthesis* ; CLOCK Proteins ; Infertility, Male/physiopathology*

In recent years, China's manned space program has advanced rapidly, with deep space exploration missions such as manned lunar landing steadily progressing, leading to a significant extension of astronauts' duration in outer space. In this context, the impact of the space magnetic field environment on astronaut health has become increasingly conspicuous. Characterized by its complexity, the spatial magnetic field indirectly regulates the circadian rhythm system by interfering with mitochondrial functions, such as electron transport chain activity, ATP synthesis efficiency, and reactive oxygen species (ROS) balance. This disruption can lead to circadian misalignment, sleep disorders, metabolic dysregulation, and other issues, severely compromising astronauts' physical and mental well-being, as well as mission performance. Currently, researchers have carried out extensive investigations into the influence of the space magnetic environment on circadian rhythms. Nevertheless, due to disparities in magnetic field parameters, exposure durations, and the model organisms employed in experiments, the results have been inconsistent. This review systematically elaborates on ground-based simulation technologies for spatial magnetic field environments and their applications, summarizes the effects of magnetic fields with varying intensities and types on core circadian rhythm biomarkers in model organisms and humans, and explores the underlying molecular and physiological mechanisms of magnetic field-induced circadian rhythm perturbation. This work aims to deepen the understanding of the mechanisms of the space magnetic environment on biological rhythms, and establish a scientific basis for formulating adaptive protective strategies centered on circadian regulation for astronauts, thereby ensuring the successful implementation of long-term deep-space missions.
Circadian Rhythm/physiology* ; Humans ; Magnetic Fields/adverse effects* ; Space Flight ; Animals ; Extraterrestrial Environment