Biology subjects

Jurado, S.

Publications and source records attributed to Jurado, S..

6 recordsLinked to original sources

bioRxiv2026

Internal decay in living trees: a quantitative tomography framework and its application in a temperate forest

Internal decay in living trees is an important component of carbon and nutrient cycling as well as species and structural diversity maintenance in forest ecosystems. We used sonic and electrical resistance tomography to evaluate and compare the prevalence and severity of stem decay in 57 living trees among four common species (Acer rubrum L., Nyssa sylvatica Marsh., Quercus rubra L., and Tsuga canadensis (L.) Carriere)) with overlapping and non-overlapping distributions across wetland and upland habitat types at the Harvard Forest in Petersham, MA, USA. Independent of tree size, site identity best explained variation in the prevalence of decay across trees sampled, whereas species identity best explained the severity of decay. We categorized trees as having no decay, incipient decay, active decay, or cavities based on combined sonic and electrical resistance metrics, the latter generated by a custom image analysis application. About 31% of wetland trees exhibited incipient decay (compared to 11% in the upland), whereas about 32% of upland trees exhibited active decay (compared to 10% in the wetland). Our study highlights a new quantitative framework for decay categorization through normalized principal component analysis (PCA) and decay analysis software that complements dual tomographic methodology for future investigations of ecological drivers of decay presence and susceptibility.

ecology↗

bioRxiv2026

Contrasting controls on tree methane emissions in upland and wetland forests

Trees can produce, consume, transport, and emit methane (CH), yet the environmental controls and mechanisms underlying these fluxes remain poorly understood. We combined 1,640 stem-chamber observations (2023-2025) with tower-based meteorology, soil moisture and temperature networks, water table monitoring, and non-destructive tomography to test how hydrology, energy balance, species identity, and internal wood condition regulate stem CH flux. Wetland trees emitted approximately 40-fold more CH than upland trees (1.96 vs. 0.05 nmol m-{superscript 2} s-{superscript 1}). At the wetland, a three-way interaction between soil temperature, water table depth, and species explained 65% of flux variance, consistent with soil-derived CH transport through stems. The wetland specialist Nyssa sylvatica emitted an order of magnitude more CH than co-occurring generalists, likely reflecting flood-tolerance adaptations that enhance gas transport. In contrast, upland fluxes showed minimal environmental control (R{superscript 2} < 9%), with most variance occurring as unexplained temporal variation within individual trees--a pattern suggesting competing methanogenic and methanotrophic processes operating near equilibrium. Internal wood condition, assessed via acoustic and electrical resistance tomography, had opposite effects across sites: decay increased emissions in upland trees, likely by creating anaerobic microsites for in situ production, while decay decreased net emissions in wetland trees, likely by impairing transport of soil-derived CH more than it enhanced in situ production. Together, these results indicate that the dominant controls on tree CH flux differ fundamentally between wetland and upland forests, underscoring the need to represent hydrologic setting, species composition, and tree condition when scaling forest CH contributions to regional budgets.

ecology↗

bioRxiv2025

Expression Atlas Of Dmrt Genes Across Sex And Development: Functional Insights From The Mouse Olfactory System

The ancient DMRT family of transcription factors has been proposed as evolutionarily conserved effectors of sexual differentiation. While brain sexual differentiation has traditionally been attributed to the sex chromosome complement (XX or XY) and steroid sex hormones, the downstream effector mechanisms controlled by these factors remain elusive. To elucidate the role of Dmrts in the mammalian brain sexual differentiation, we generated a comprehensive expression atlas for all family members (Dmrt1-7) in the mouse brain. We used in situ hybridization to examine both sexes across various developmental stages. Our findings revealed that all Dmrts, except Dmrt7, are expressed in the brain. This study expands our understanding of the DMA-Dmrt subfamily beyond pallial structures and identifies their expression maintenance in adult neurogenic sites. For the first time, we described the neuronal expression of Dmrt2 and Dmrt6. Mouse Dmrts did not exhibit clear sexually dimorphic patterns but showed quantitative differences in expression levels between the sexes. We demonstrated that most Dmrts are maintained in postmitotic neurons during both embryonic and postnatal stages, suggesting potential interactions with steroid hormones during organizational and activational phases. As proof of concept, our comprehensive analysis of Dmrt5 expression revealed its prominent presence in the mouse olfactory system, which is fundamental for controlling sex-specific innate behaviors. The absence of Dmrt5 affects the main olfactory epithelium, where sensory neurons are located; however, mis-patterning phenotypes observed in the olfactory bulb and the piriform cortex distinctly affect male and female embryos, revealing the interaction of Dmrt5 with sex in deeper integrative layers of innate neural circuits. Our results provide a valuable resource for uncovering novel sites and mechanisms of sexual differentiation in the mammalian nervous system, potentially contributing to the sex bias observed in the prevalence and symptomatology of psychiatric disorders.

developmental biology↗

bioRxiv2023

Combined KRASG12C and SOS1 inhibition enhances and extends the anti-tumor response in KRASG12C-driven cancers by addressing intrinsic and acquired resistance

Efforts to improve the anti-tumor response to KRASG12C targeted therapy have benefited from leveraging combination approaches. Here, we compare the anti-tumor response induced by the SOS1-KRAS interaction inhibitor, BI-3406, combined with a KRASG12C inhibitor (KRASG12Ci) to those induced by KRASG12Ci alone or combined with SHP2 or EGFR inhibitors. In lung cancer and colorectal cancer (CRC) models, BI-3406 plus KRASG12Ci induces an anti-tumor response stronger than that observed with KRASG12Ci alone and comparable to those by the other combinations. This enhanced anti-tumor response is associated with a stronger and extended suppression of RAS-MAPK signaling. Importantly, BI-3406 plus KRASG12Ci treatment delays the emergence of acquired adagrasib resistance in both CRC and lung cancer models and is associated with re-establishment of anti-proliferative activity in KRASG12Ci-resistant CRC models. Our findings position KRASG12C plus SOS1 inhibition therapy as a promising strategy for treating both KRASG12C-mutated tumors as well as for addressing acquired resistance to KRASG12Ci.

cancer biology↗

bioRxiv2022

Natural and pathological aging distinctively impact the vomeronasal system and social behavior

Normal aging and many age-related disorders such as Alzheimers disease cause deficits in olfaction, however it is currently unknown how natural and pathological aging impact the detection of social odors which might contribute to the impoverishment of social behavior at old age further worsening overall health. Here, we investigated the effect of aging in the recognition of social cues and the display of social behavior. Our findings indicate that aging distinctively disrupts the processing of social olfactory cues decreasing social odor exploration, discrimination and habituation in both wild type senescent (2-year-old) mice and in 1-year-old double mutant model of Alzheimers disease (APP/PS1Het). Furthermore, social novelty was diminished in 1-year-old APP/PS1Het mice, indicating that alterations in the processing of social cues are accelerated during pathological aging. Analysis of the vomeronasal organ, the main gateway to pheromone-encoded information, indicated that natural and pathological aging distinctively reduce the neurogenic ability of the vomeronasal sensory epithelium. Cell proliferation remained majorly preserved in 1-year model of Alzheimers disease (APP/PS1Het), whereas naturally aged animals exhibited significant deficiencies in the number of mature, proliferative and progenitor cells. This study reveals fundamental differences in the cellular processes by which natural and pathological aging disrupt the exploration of social cues and social behavior.

neuroscience↗

bioRxiv2020

Specification of oxytocinergic and vasopressinergic circuits in the developing mouse brain

Oxytocin (OXT) and arginine vasopressin (AVP) support sex-specific and context-appropriate social behaviors. Although alterations of these systems underlie the appearance of neuropsychiatric disorders, their formation and developmental dynamics remain largely unknown. Using novel brain clearing techniques and 3D imaging, we have reconstructed the specification of oxytocinergic and vasopressinergic circuits in the developing mouse brain with unprecedented cellular resolution. A systematic quantification indicates that OXT and AVP neurons in the hypothalamus display distinctive dynamics, but also share common features as a high cellular plasticity from embryonic to early postnatal stages. Our findings reveal new insights into the appearance and consolidation of neuropeptidergic systems in the developing CNS which is a critical step to unveil brain formation and function.

neuroscience↗