Biology subjects

Gallo, V.

Publications and source records attributed to Gallo, V..

10 recordsLinked to original sources

bioRxiv2026

Divergent Pontine and Cerebellar Pathology in Preterm Infants With Necrotizing Enterocolitis

Importance: Preterm survivors of necrotizing enterocolitis (NEC) face substantial neurodevelopmental impairment, but the regional biology and timing of associated brain abnormalities remain poorly defined. Objective: To define the regional, cellular, molecular, and temporal features of NEC-associated brain pathology. Design: Prospective multimodal clinical cohort study (2012-2024), complemented by postmortem tissue analyses. Setting: Level IV neonatal intensive care unit at Children's National Hospital, Washington, DC. Participants: Of 400 infants screened, 253 preterm infants born before 37 weeks' gestation (128 with NEC and 125 without NEC) were included across neuroimaging, plasma metabolomic, and postmortem cohorts. Exposures: Medical or surgical NEC (modified Bell stage [≥]II). Main Outcomes and Measures: Primary outcomes were term-equivalent magnetic resonance imaging (MRI) abnormalities and serial ultrasound hindbrain growth; secondary outcomes were postmortem histopathology, brain and intestinal transcriptomics, and plasma metabolomics. Results: Among 179 infants with term-equivalent MRI (89 NEC, 90 controls; 102 [57.0%] male; mean [SD] gestational age, 26.3 [2.2] weeks), NEC was associated with a higher prevalence of pontine abnormalities (12.4% vs 1.1%; adjusted prevalence ratio, 9.14; 95% CI, 1.16-71.92), alongside white matter, callosal, and cerebellar abnormalities. In postmortem tissue (n = 27), white matter pathology qualitatively resembled that of prematurity, whereas the hindbrain showed distinct regional phenotypes. The cerebellum exhibited external granular layer contraction (42% reduction; P = .04), while the pons showed neuronal injury with increased morphological apoptotic burden (P [≤] .05). Brain and intestinal transcriptomics (n = 14), complemented by plasma metabolomics (n = 29), revealed divergent inflammatory and metabolic signatures. The pons showed increased neuroinflammatory and reduced mitochondrial programs, whereas the cerebellum showed reduced metabolic and cell-cycle programs alongside circulating lysophospholipid depletion. Serial ultrasonography (n = 159), anchored to the cohort mean NEC onset age of 29 weeks' postmenstrual age, identified earlier cerebellar dimensional deficits (P = .015) and later pontine growth deceleration (P < .001). Conclusions and Relevance: In this cohort study, NEC-associated hindbrain pathology showed asynchronous growth patterns accompanied by distinct cellular and molecular phenotypes. These findings support investigation of regional vulnerability and stage-specific neuroprotection; individual injury timing and causal mechanisms remain unresolved.

neuroscience↗

bioRxiv2026

Developmental Arrest Associated with Altered Cerebellar Metabolism in Sudden Infant Death Syndrome

BackgroundEffective autoresuscitation during hypoxic stress demands the cerebellum integrate autonomic and arousal responses. It remains unknown if the SIDS cerebellum possesses the metabolic stability and developmental maturity to sustain this function. We aimed to define if cerebellar dysfunction constitutes a silent failure point within the central respiratory network. MethodsWe performed multi-omic integration of RNA-sequencing, targeted metabolomics, and quantitative histology on postmortem cerebellar tissue from SIDS infants and age-matched controls. Cross-omic concordance analysis mapped the relationship between metabolite abundance and the transcriptional directionality of corresponding metabolic enzymes. ResultsThe SIDS cerebellum revealed a distinct profile defined by neuroinflammation and altered GABA and glutamate metabolism. Targeted metabolomics confirmed a metabolic imbalance with significantly elevated glutamate and GABA (P < 0.05). Quantitative histology exposed concurrent developmental arrest; persistent external granule layers highlighted morphological immaturity, explaining the failure to mount effective compensatory responses. ConclusionsMetabolic pathology in the SIDS cerebellum is intrinsically linked to structural immaturity. This developmental arrest creates a compromised environment lacking the metabolic competence to support neural homeostasis, preventing critical arousal responses required for survival. ImpactO_LIMulti-omic and neuropathological analysis reveal that structural immaturity in SIDS cerebellum is directly linked to neuroinflammation and metabolic excitotoxicity. C_LIO_LIDevelopmental arrest leaves the tissue metabolically incompetent to support the neural homeostasis required for infant survival during hypoxic stress. C_LIO_LIThis study shifts the focus of SIDS pathology beyond traditional brainstem mechanisms by establishing the cerebellum as a critical, point of failure within the central respiratory network, providing a direct link between morphological delay and functional neurochemical disruption C_LIO_LIThese findings offer translatable paradigm for understanding SIDS vulnerability and identify specific metabolic targets for future diagnostic risk screening and therapeutic interventions. C_LI

neuroscience↗

bioRxiv2025

Intrinsic Gestational Timing Governs Human Cerebellar Development After Preterm Birth

Intrinsic programs shape brain maturation, yet which are perturbed by prematurity, and the molecular pathways involved remain unknown. The human cerebellum serves as a paradigm of extrauterine development; its accelerated growth and circuit formation align with the third trimester, a period disrupted by preterm delivery. Through multimodal datasets encompassing in vivo neuroimaging and neurodevelopmental outcomes with postmortem spatial-transcriptomic and histopathological profiling, we show that prematurity diverts the cerebellar developmental trajectory. Cerebellar growth and functional outcomes scaled with gestational age, despite modifying perinatal exposures. Spatially resolved developmental programs underlying macroscopic trajectories were marked by incomplete granule cell maturation and impaired Purkinje cell structural refinement, indicating lineage-specific developmental asynchrony. Thus, prematurity constitutes biologically displaced maturation, in which infants of equivalent post-menstrual age occupy divergent developmental states.

neuroscience↗

bioRxiv2025

Prematurity Reprograms Cerebellar Development and Long-Term Behavior

Preterm survivors often develop motor and socio-cognitive impairments that implicate altered cerebellar development, yet the underlying mechanisms remain poorly understood. A key challenge is that prematurity involves overlapping perinatal insults that converge on the developing brain, making their individual effects difficult to disentangle. Here, we model two major prematurity-associated insults, maternal immune activation (MIA) and neonatal hypoxia (Hx), in mice. By controlling timing and sequence, we define how these insults shape cerebellar assembly during rapid maturation. Comparative analysis with human tissue confirmed that these insults recapitulate key features of the human preterm cerebellum, establishing the translational validity of this model for dissecting insult-specific outcomes. Behavioral and kinematic profiling revealed divergent motor and social phenotypes, which we traced to insult-specific cerebellar remodelling. Hypoxia compromised both granule cell maturation in the internal granule layer and the principal excitatory afferents to Purkinje cells, a circuit state that manifested as impaired motor execution and stereotyped, sensory-disengaged social investigation. Maternal immune activation, by contrast, expanded the granule cell progenitor layer and reduced Purkinje cell dendritic complexity, a phenotype that preserved social preference but reorganized the kinematic structure of social investigation. When hypoxia followed maternal immune activation, it acted on this primed substrate to produce a distinct state in which the features established by prior inflammation were compounded by granule cell proliferative arrest, progressive mitochondrial dysfunction, and aberrant, hyper-interactive social investigation. Together, these findings reframe prematurity-associated insults as cerebellar reprogramming events shaped by both the identity and sequence of insults, linking distinct mechanistic substrates to divergent neurodevelopmental outcomes.

neuroscience↗

bioRxiv2025

Cerebellum and Plasma Metabolomics Identify Sepsis Biomarkers and MSC-sEV-Mediated Rescue

Septic encephalopathy (SE) is a severe complication of sepsis, characterized by neuroinflammation and metabolic dysfunction, with the cerebellum among the most vulnerable brain regions. Advances in the field have been constrained by the lack of reliable biomarkers for SE detection, incomplete mapping of cerebellar metabolic alterations in SE, and limited insight into the therapeutic mechanisms of human mesenchymal stem cell (MSC)-derived small extracellular vesicle (sEV) therapy. To overcome these challenges, we used a murine sepsis model and conducted integrated metabolomic analyses of cerebellar tissue and plasma, with and without MSC-sEV administration. Cross-compartment analyses identified six plasma metabolites with strong diagnostic potential in mice, three of which (n-acetylputrescine, aspartic acid, and cystathionine) were also observed in the plasma of human septic patients, supporting their promise as translatable biomarker candidates. Sepsis triggered profound cerebellar metabolic dysfunction, suppression of oxidative energy metabolism, and redox imbalance. MSC-sEVs attenuated these disturbances via their bioactive cargo, restoring cellular energetics and reestablishing antioxidant balance. Collectively, these results highlight cross-species plasma biomarkers for SE diagnosis, delineate key cerebellar metabolic mechanisms in SE, and demonstrate therapeutic modulation by human MSC-sEVs.

neuroscience↗

bioRxiv2024

Bumblebee visual learning: simple solutions for complex stimuli

Natural visual stimuli are typically complex. This presents animals with the challenge of learning the most informative aspects of these stimuli while not being confused by variable elements. How animals might do this remains unclear. Here, we tested bumblebees ability to learn multicomponent visual stimuli composed of a simple constant bar element and a grating element that was consistent in orientation but varied in width and number of gratings. Bees rapidly and successfully learned these compound stimuli. Tests revealed learning of the single bar element was more robust than learning of the grating element. Our study highlights how even small-brained invertebrates can rapidly learn multicomponent stimuli and prioritise the most consistent elements within them. We discuss how the learning phenomena of generalisation and overshadowing may be sufficient to explain these findings, and caution that complex cognitive concepts are not necessary to explain the learning of complex stimuli. HighlightsO_LIBumblebees are highly efficient in prioritising the most consistent elements in multicomponent visual stimuli. C_LIO_LIBees trained on horizontal and vertical cues exhibit differences in how they memorise visual cues. C_LIO_LITwo phenomena can explain how bees preferentially select, memorise and use visual cues in this experiment: generalisation and overshadowing. C_LIO_LIBumblebees as generalist foragers are well-suited to study visual cognition. C_LI

animal behavior and cognition↗

bioRxiv2022

Honeycomb cell walls are plastic; initially built as curves the walls are reformed by bees during subsequent construction

Honeybee comb comprises recognisable hexagons, each with straight sides. Not only are the cell side-walls flat, but so too are those that form the base of cells; base faces which are shared with cells on the opposite face of the comb. The mechanism by which bees build cells with flat sides has been the subject of speculation for centuries, but it has been conjectured by Kepler, Darwin as well as more recent researchers that bees build cylindrical cells that are transformed into flat sided prisms, without consensus as to the process by which this is achieved. By offering bees shaped wax stimuli and observing the comb that was built upon them, we have shown that under certain conditions walls will be curved and others where walls are reformed to be flat. A wall of a cell, be it a side-wall or a face of the base, with no other cell beyond it will be built as a convex curve whereas a wall with a cell to both sides will be formed flat. Furthermore, we show that these walls are plastic; walls that were initially built curved were re-shaped to be flat once a second adjacent cell had been built.

animal behavior and cognition↗

bioRxiv2019

Evaluation of bacterial proliferation with a microfluidic-based device: Antibiochip.

The measurement of the proliferation (and the relevant inhibition of proliferation) of microbes is used in different settings, from industry to laboratory medicine. Thus, in this study, the capacity of the Antibiochip (ELTEK spa), a microfluidic-based device, to measure the amount of E. coli in certain culture conditions, was evaluated. An Antibiochip is composed of V-shaped microchannels, and the amount of microparticles (such as microbes) is measured by the surface of the pellet after centrifugation. In the present study, different geometries, volumes and times were analyzed. When the best conditions were identified, serial dilutions of microbial cultures were tested to validate the linearity of the results. Then, with the use of wild E. coli strains isolated from medical samples, the relationship between bacterial susceptibility to antibiotics (gentamicin, amikacin and ceftriaxone) measured by standard methods and that measured by the Antibiochip was evaluated. In this report, the good quality performances of the methods, their linearity and the capacity to identify susceptible microbial strains after 60 minutes of incubation are shown. These results represent a novel approach for ultrarapid antibiograms in clinics.

microbiology↗

bioRxiv2019

Placental neurosteroids shape cerebellar development and social behaviour

Compromised placental function or premature loss has been linked to diverse neurodevelopmental disorders 1,2. The placenta is the first functional foetal endocrine organ, but the direct impact of placental hormone loss on foetal brain in late gestation has not been empirically tested. Allopregnanolone (ALLO) is a non-glucocorticoid, progesterone derivative that acts as a positive modulator of GABA-A receptor activity3 with the potential to alter critical GABA-mediated developmental processes 4,5. To directly test the role of placental ALLO, we generated a novel mouse model in which the gene encoding the synthetic enzyme for ALLO (Akr1c14) is specifically deleted in trophoblasts using a tissue-specific Cre-Lox strategy. ALLO concentrations are significantly decreased in late gestation in placenta and brain when placental Akr1c14 is removed, indicating placenta as the primary gestational ALLO source. We now demonstrate that targeted placental ALLO loss leads to permanent changes in brain development in a sex- and regionally-specific manner. Placental ALLO insufficiency led to male-specific cerebellar white matter (WM) abnormalities characterized by excess myelination with increased myelin protein expression, similar to changes reported in boys with autism spectrum disorders (ASD)6,7. Behavioural testing of these mice revealed increased repetitive behaviour and sociability deficits, two hallmarks of ASD, only in male offspring with placental ALLO insufficiency. Notably, a strong positive correlation was seen between the cerebellar contents of myelin basic protein (MBP) and the severity of ASD-like behaviours. A single injection of ALLO during gestation was sufficient to rescue both cerebellar MBP levels and aberrant behaviours. This study reveals a new role for a placental hormone in shaping specific brain structures and behaviours, and suggests that identifying placental hormone insufficiency or preterm loss may offer novel therapeutic opportunities to prevent later neurobehavioural disorders.

neuroscience↗

bioRxiv2019

Cranial anatomy of the predatory actinopterygian Brazilichthys macrognathus from the Permian (Cisuralian) Pedra de Fogo Formation, Parnaiba Basin, Brazil

ABSTRACTBrazilichthys macrognathus is the only named actinopterygian from the Permain (Cisuralian) Pedra de Fogo Formation of northeastern Brazil, where it is represented by a single three-dimensionally preserved but incompletely described skull of unclear systematic placement. We used X-ray computed microtomography (μ-CT) to better document its anatomy and phylogenetic affinities. μ-CT reveals parts of the internal skeleton. We correct errors in original description, including the number of infraorbital bones and the misidentification of the dermosphenotic as sclerotic ossifications. These reinterpretations of external anatomy are joined by new data on internal structure, including the palate, parasphenoid, and branchial and hyoid arches. A maximum parsimony analysis of anatomical data resolves Brazilichthys as a stem actinopterygian, crownward of all Devonian species. This placement is supported by the absence of a dermosphenotic posterior ramus and the presence of opercular process of the hyomandibula. A similar placement is suggested by a Bayesian analysis of this same dataset, although relationships throughout the tree are less resolved. Our results reject previous interpretations of Brazilichthys as a relative of Birgeriidae, a Triassic group consistently placed within the actinopterygian crown. Although Acrolepis is too poorly known to be included in our analysis, we also reject a close relationship between this taxon and Brazilichthys, as their only shared similarities appear to be broadly distributed among early actinopterygians.View Full Text

paleontology↗