Unprecedented suppression of Panama's Pacific upwelling in 2025.

The Gulf of Panama's (GOP) seasonal upwelling system has consistently delivered cool, nutrient-rich waters via northerly trade winds every January-April for at least 40 y. Here, we document the failure of this normally highly predictable phenomenon in 2025. Data suggest that the cause was a reduction in Panama wind-jet frequency, duration, and strength, possibly related to the Intertropical Convergence Zone (ITCZ) position during the 2024-2025 La Niña, though the mechanisms remain unclear.

Historical ecology of the Southern Central American Pacific coast.

The Pacific coast of the Southern Central American Isthmus is a highly productive and biodiverse region with a rich human history. Although the interaction of the oceans, climate, biodiversity and early human systems has shaped the region's ecology, research has remained largely disconnected, arising independently from discrete disciplines. To unite this disparate research, we reviewed and synthesized the historical ecology of the Isthmus from the Last Glacial Maximum to the rise of industrial fishing in the 1950s.

Prehistoric archives reveal evidence of predator loss and prey release in Caribbean reef fish communities.

Understanding how humans have altered coral reef food webs remains challenging due to the absence of prehistoric baselines. Here, we use fish remains preserved in fossil and archaeological deposits from Panamá and the Dominican Republic to explore how Caribbean reef fish mortality patterns have changed over millennia. By quantifying accumulation rates of shark dermal denticles (scales) and bony fish otoliths (ear stones) in reef sediments, we assess relative fish abundance, while otolith size serves as a proxy for body size at death.

Biodistance Analysis via Dental Phenotypic Diversity in Early Collective Burials at Cerro Juan Díaz, Panamá (30-650 CE) [Análisis de Biodistancia Mediante la Diversidad Fenotípica Dental en los Entierros Colectivos Tempranos del Cerro Juan Díaz, Panamá (30-650 EC)].

Objectives: Burial space reuse and prolonged interaction with the dead were common practices in the Isthmo-Colombian Area, dating back to at least the Early Ceramic Period in the Greater Coclé region. However, biological and social relationships of individuals interred in collective burial contexts remain unclear. Here, we explore intra-cemetery biological variation through a biological distance analysis of individuals interred in large mortuary features from the first mortuary horizon at the site of Cerro Juan Díaz in Panamá.

Coral carbonate-bound isotopes reveal monsoonal influence on nitrogen sources in Southeastern China's Greater Bay Area from the mid-Holocene until the Anthropocene.

Most anthropogenic nitrogen (N) reaches coastal waters via rivers carrying increasing loads of sewage, fertilizer, and sediments. To understand anthropogenic N impacts, we need to understand historical N-dynamics before human influence. Stable isotope ratios of N preserved in carbonates are one way to create temporal N records.

Protocol to track the biosynthesis of cholesterol in cultured HCC cells using C compound-specific stable isotopic tracers.

Cholesterol biosynthesis supports proliferation and drives resistance to tyrosine kinase inhibitor (TKI) therapy in hepatocellular carcinoma (HCC). Here, we present a protocol for using stable isotopic tracers to track the biosynthesis of cholesterol in cultured HCC cells. We describe steps for cell preparation, incubation, separation, and homogenization.

Improving stable isotope assessments of inter- and intra-species variation in coral reef fish trophic strategies.

Fish have one of the highest occurrences of individual specialization in trophic strategies among Eukaryotes. Yet, few studies characterize this variation during trophic niche analysis, limiting our understanding of aquatic food web dynamics. Stable isotope analysis (SIA) with advanced Bayesian statistics is one way to incorporate this individual trophic variation when quantifying niche size.

Insights from Fossil-Bound Nitrogen Isotopes in Diatoms, Foraminifera, and Corals.

Nitrogen is a major limiting element for biological productivity, and thus understanding past variations in nitrogen cycling is central to understanding past and future ocean biogeochemical cycling, global climate cycles, and biodiversity. Organic nitrogen encapsulated in fossil biominerals is generally protected from alteration, making it an important archive of the marine nitrogen cycle on seasonal to million-year timescales. The isotopic composition of fossil-bound nitrogen reflects variations in the large-scale nitrogen inventory, local sources and processing, and ecological and physiological traits of organisms.

Caspase-3-Induced Activation of SREBP2 Drives Drug Resistance via Promotion of Cholesterol Biosynthesis in Hepatocellular Carcinoma.

Unlabelled: Accumulating evidence has demonstrated that drug resistance can be acquired in cancer through the repopulation of tumors by cancer stem cell (CSC) expansion. Here, we investigated mechanisms driving resistance and CSC repopulation in hepatocellular carcinoma (HCC) as a cancer model using two drug-resistant, patient-derived tumor xenografts that mimicked the development of acquired resistance to sorafenib or lenvatinib treatment observed in patients with HCC. RNA sequencing analysis revealed that cholesterol biosynthesis was most commonly enriched in the drug-resistant xenografts.

Coral reef diversity losses in China's Greater Bay Area were driven by regional stressors.

Observations of coral reef losses to climate change far exceed our understanding of historical degradation before anthropogenic warming. This is a critical gap to fill as conservation efforts simultaneously work to reverse climate change while restoring coral reef diversity and function. Here, we focused on southern China's Greater Bay Area, where coral communities persist despite centuries of coral mining, fishing, dredging, development, and pollution.

Megacity development and the demise of coastal coral communities: Evidence from coral skeleton δ N records in the Pearl River estuary.

Historical coral skeleton (CS) δ O and δ N records were produced from samples recovered from sedimentary deposits, held in natural history museum collections, and cored into modern coral heads. These records were used to assess the influence of global warming and regional eutrophication, respectively, on the decline of coastal coral communities following the development of the Pearl River Delta (PRD) megacity, China. We find that, until 2007, ocean warming was not a major threat to coral communities in the Pearl River estuary; instead, nitrogen (N) inputs dominated impacts.