UC Davis

Nuclear positioning drives developmental processes from fertilization to neurogenesis. The linker of nucleoskeleton and cytoskeleton (LINC) complex connects nuclei to cytoskeletal force generators that power nuclear migration. Mutations in LINC complex components cause muscular dystrophies and neurodegenerative disorders, yet mechanisms controlling nuclear movement remain poorly understood. We summarize advances from three C. elegans developmental models in different mechanical environments: pronuclear migration across the vast zygotic cytoplasm, hyp7 hypodermal precursor nuclear migration where nuclei span nearly the width of the cell, and P-cell nuclear migration through narrow constrictions. These systems reveal multiple regulatory strategies for nuclear movement. Tissue-specific expression of distinct SUN-KASH combinations determines which cytoskeletal elements engage nuclei. Alternative splicing generates KASH isoforms with opposing motor preferences, and P-cell nuclear migration through constrictions requires four parallel pathways. These findings establish conserved mechanistic principles of nuclear migration, with implications for development, immune cell function, and cancer metastasis.

Background: Laparoscopic liver resection (LLR) is widely performed for the treatment of liver diseases. Effective postoperative pain control is essential, particularly in patients vulnerable to opioid-related complications due to impaired hepatic function. This study compared the analgesic efficacy and recovery outcomes of ultrasound-guided erector spinae plane block (ESPB) and subcostal transversus abdominis plane block (TAPB) in patients undergoing LLR. Methods: In this single-center randomized controlled trial (ChiCTR2300078378), 120 patients scheduled for LLR were randomly allocated to receive ESPB, subcostal TAPB, or standard care (CON). The primary outcomes were postoperative pain scores at rest and during coughing. Secondary outcomes included cumulative opioid consumption, time to first patient-controlled intravenous analgesia (PCIA) activation, rescue analgesia use, and effective PCIA requests. Early recovery outcomes included time to ambulation, first flatus, length of hospital stay, Quality of Recovery-15 (QoR-15) scores, and adverse events. Results: All 120 patients were included in the analysis. Significant time-by-group interactions were observed for postoperative NRS pain scores at rest and during coughing (P=0.004 and P = 0.003). At 2 hours postoperatively, the estimated mean differences in coughing NRS score were -1.03 points (95% CI, -1.60 to -0.45; P < 0.001) for subcostal TAPB versus CON and -1.15 points (95% CI, -1.73 to -0.57; P < 0.001) for ESPB versus CON. The estimated difference between ESPB and subcostal TAPB was -0.13 points (95% CI, -0.70 to 0.45; P = 1.000). Both blocks reduced cumulative opioid consumption, prolonged time to rescue analgesia, and decreased rescue analgesia events and effective PCIA demands. QoR-15 scores at 24 hours were higher in both block groups compared with control, whereas scores at 30 days were similar among groups. No significant between-group differences were observed in the recorded adverse events. Conclusion: In this single-center randomized trial, both subcostal TAPB and ESPB provide effective opioid-sparing analgesia and improve early recovery after LLR. Neither technique demonstrated consistent superiority across postoperative pain trajectories, suggesting that either block can be incorporated into multimodal analgesia strategies for LLR.

BACKGROUND: Whether ephedrine, when used to maintain intraoperative blood pressure, is superior to phenylephrine in reducing postoperative delirium remains uncertain. This study aims to determine whether the intraoperative management of hypotension with ephedrine, compared with phenylephrine, reduces the incidence of postoperative delirium in elderly patients undergoing major non-cardiac, non-neurosurgical surgery. METHODS: This multicentre, randomized, double-blind, controlled trial will enrol 1,084 elderly patients scheduled for elective non-cardiac and non-neurosurgical major surgeries under general anaesthesia at seven hospitals in China. Participants will be randomized in a 1:1 ratio, stratified by study centre, to receive continuous intravenous infusion of either phenylephrine or ephedrine to maintain mean arterial pressure within 20% of the baseline value. The primary outcome is the incidence of postoperative delirium within 7 days after surgery. Secondary outcomes include severity of postoperative delirium, numeric rating scale pain scores at rest and during activity at 24, 48 and 72 h postoperatively, intensive care unit (ICU) admission rate and length of ICU stay, length of postoperative hospital stay, incidence of in-hospital major adverse cardiovascular and cerebrovascular events (myocardial infarction, arrhythmia, heart failure, and stroke), and 30-day all-cause mortality. DISCUSSION: We hypothesize that ephedrine, when used to maintain intraoperative blood pressure, is superior to phenylephrine in reducing postoperative delirium in elderly patients undergoing major non-cardiac, non-neurosurgical surgery. The findings of this study may provide high-quality evidence for optimizing the management of intraoperative hypotension in this vulnerable population. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2500115385).

Uterine luminal fluid influences embryonic development and the subsequent phenotype of offspring, yet its detailed metabolomic composition remains poorly characterized. Here, minimally invasive transcervical techniques were employed to collect neat uterine fluid from postpartum dairy cows and cyclic beef cows to allow for metabolomic profiling via targeted mass spectrometry. Objectives were to 1) compare the metabolomic profile of uterine fluid with plasma in dairy cows and 2) assess the impact of dietary rumen-protected methionine and stage of estrous cycle (day 0 vs 7) on plasma and uterine fluid metabolomic profile in beef cows. Results revealed that the concentrations of many metabolites, including amino acids, signaling molecules (e.g. dopamine, gamma-aminobutyric acid) and lipids (e.g. ceramides, diacylglycerols), were higher in uterine fluid than in plasma. An oral bolus of rumen-protected methionine increased uterine concentration of methionine on day 0 of the estrous cycle. The uterine metabolome remained relatively stable between days 0 and 7 although there was temporal variability for a select number of metabolites (cysteine, methionine, methionine sulfoxide, asymmetric dimethylarginine, ceramides, and glycerophospholipids). Correlations between plasma and uterine fluid concentrations were strong or moderate for many amino acids. Collectively, these findings highlight that the uterine lumen is a specialized, selectively regulated biochemical compartment.

In this study, a medium-term oven aging (MTOA) protocol of 20 h at 100 °C was applied to loose plant-produced mixes to evaluate the age-related and fatigue cracking resistance of asphalt mixes containing recycled materials. To evaluate the age-related cracking resistance, the indirect tensile IDEAL cracking tolerance test was performed on 27 plant-produced mixes, and fatigue cracking resistance was evaluated using the four-point bending (4PB) test on four selected mixes. MTOA resulted in an increase in strength and a reduction of the cracking tolerance index (CTIndex), while the fracture energy did not change much. Overall, the indirect tensile strength increased on average by 150 kPa (somewhat uniform shift for different mix types), and the CTIndex decreased by approximately 38% on average, indicating that the change in the CTIndex value depended on the short-term aged value. Based on 4PB test results, MTOA resulted in an increase of the dynamic modulus of the four mixes between 10% and 30% at 20 °C and 1 Hz, and a reduction of approximately 50% for the 4PB fatigue life for three out of the four mixes at strain levels of 400–700 µε, which are typical of thin overlays on cracked pavements. The fourth mix showed little effect of MTOA on 4PB fatigue life.

As precipitation regimes intensify and engineered recharge expands, the vadose zone faces increasingly dynamic wetting–drying cycles that generate redox oscillations and alter geogenic contaminant mobility. Oxygen depletion and microbial respiration can dissolve Fe and Mn (oxyhydr)oxides, key sorption hosts for arsenic (As), chromium (Cr), uranium (U), and related trace elements, producing transient, element-specific, and history-dependent responses. Synthesizing field observations, laboratory experiments, and large-scale monitoring datasets, we identify three management-relevant insights. First, contaminant mobilization under flashy hydrology can occur in short-lived pulses lasting hours to days, faster than typical groundwater-monitoring intervals. Second, single-contaminant frameworks can misrepresent overall geogenic risk because the same wetting event may mobilize arsenic through reductive dissolution while attenuating chromium and uranium through reduction to less mobile forms. Third, repeated wetting–drying cycles may alter or deplete reactive Fe and Mn mineral phases that buffer contaminant release, increasing vulnerability under sustained hydrologic variability. Changing geogenic contaminant concentrations in US municipal groundwater over the past three decades indicate that these processes are already detectable at network scales. Addressing them requires event-scale, multi-element monitoring and process-based models that represent redox hysteresis and mineral transformations from the vadose zone to the aquifer.

Purpose of Review: This review summarizes the most recent literature on the association between the administration of blood products with acute kidney injury (AKI). The multifactorial nature of AKI is reviewed and the potential mechanisms for the association are explored. In addition, immunological causes of AKI after transfusion are addressed. We also provide recommendations for transfusion practice and perioperative management to minimize the risk of AKI. Recent Findings: Several recent studies have demonstrated a consistent association between the administration of blood products and AKI. Restrictive blood transfusion protocols have however failed to reduce the incidence of AKI. Summary: Transfusion of blood products is definitively associated with AKI. Considering current evidence however it is still unknown if there is a cause-and-effect relationship underlying this association. Notwithstanding the uncertainty, blood products should be employed with great caution in patients who are at significant risk of AKI until further evidence becomes available to clarify the situation. The etiology of AKI is multifactorial, and factors other than transfusion may be more important. Intraoperative hypotension must be prevented. The use of drugs which have the potential for renal toxicity like intravenous contrast agents, aminoglycoside antibiotics and non-steroidal analgesic drugs should be minimized. Adequate fluid resuscitation is also necessary to guarantee adequate cardiac output and renal perfusion. Goal-directed fluid management should be considered in high-risk patients. Transfusion of incompatible blood products must also be avoided as at all costs because this can lead to severe AKI.

Microplastic (particles <5 mm) is an emerging environmental concern that threatens aquatic ecosystems worldwide. While extensive research has documented the ubiquity of microplastic in marine and coastal environments and its assimilation by organisms at all trophic levels, comparatively little is known about microplastic occurrence in rural riverine ecosystems. Even less information exists for salmon-bearing streams, where microplastic pollution may hinder salmonid conservation and recovery efforts. We examined the presence and concentration of microplastic in Scott Creek, a small coastal California (USA) watershed with minimal urban development. Our study quantified suspended microplastic in surface waters and in the gastrointestinal (GI) tracts of juvenile Steelhead Trout (Oncorhynchus mykiss). Microplastic was detected in 93 % of water samples, indicating that Scott Creek routinely transports and cycles microplastic. Concentrations were higher in late summer than in spring, although monthly spatial patterns were largely consistent among sites. In juvenile steelhead, 60.6 % of GI tracts contained one or more types of microplastic. For both surface waters and juvenile steelhead, microplastic was predominantly small (<5 mm) dark blue, black, and transparent fiber-type particles, with fragments, shards and foams encountered less frequently. These findings suggest that fish ingest microplastic at low frequencies, or that ingested particles may pass rapidly through their digestive systems. This study provides one of the first assessments of microplastic in a minimally urbanized, salmon-bearing watershed. Our results serve as a baseline for evaluating the ecological implications of microplastic pollution in small coastal creeks and its potential to influence native salmonid populations. Data Availability The surface water and steelhead microplastic datasets generated and analyzed during the current study are publicly available via Zenodo (DOI: 10.5281/zenodo.18038857).