Biology subjects

Yazdani, F.

Publications and source records attributed to Yazdani, F..

4 recordsLinked to original sources

bioRxiv2026

Iterative co-creation of harmonized human and non-human primate cellular and structural ontologies and 3D common coordinate frameworks for the basal ganglia

A major goal of the BRAIN Initiative Cell Atlas Network (BICAN) is to create a suite of foundational reference cell atlases and associated standards for human and non-human primate brains. Central to this goal is the creation of cross-species harmonized cellular taxonomies and structural parcellations with formal ontologies that can be mapped into 3D reference frameworks bridging neuroimaging and cellular and histological resolutions. We describe here an iterative approach, focused initially on the basal ganglia, to co-create structural and cellular ontologies in human, macaque and marmoset brains, including a Harmonized Ontology of Mammalian Brain Anatomy (HOMBA), and to map and refine structural parcellations into neuroimaging-based common coordinate frameworks. These references provide the framework for documenting and mapping all experimental sampling in BICAN, allowing analyses of cellular and molecular variation as a function of topographic position, and enabling comparisons of cellular, molecular and neuroimaging-based functional variation within and between primate species. HighlightsO_LIA hierarchical Harmonized Ontology of Mammalian Brain Anatomy (HOMBA) covering 2348 structures C_LIO_LIHOMBA-annotated 3D common coordinate frameworks (CCFs) of the basal ganglia across species C_LIO_LIHistologically informed 3D parcellation/atlas of 280 human subcortical structures indexed by HOMBA C_LIO_LIMapping and integration of structural, cellular and functional data with HOMBA and CCFs C_LI

neuroscience↗

bioRxiv2025

A cross-species spatial transcriptomic atlas of the human and non-human primate basal ganglia

The basal ganglia are interconnected subcortical nuclei with complex topographical organization that orchestrate goal-directed behaviors and are implicated in neurodegenerative movement disorders. We generated a cellular-resolution, spatial transcriptomic atlas of the basal ganglia in human, rhesus macaque, and common marmoset, sampling over one million cells in each species. By integrating spatial data with a cross-species, consensus snRNA-seq cell type taxonomy, this atlas reveals conserved principles of molecular organization within and across structures. The cellular architecture is complex but highly stereotyped, with gene expression gradients superimposed onto discrete compartments. Extensive spatial sampling illuminates 3D gradients of molecular organization in the striatum and reveals cell type-specific core and shell compartments in the primate internal globus pallidus, which is conserved with mouse. This unified, cross-species spatial transcriptomic atlas will be a foundational resource for characterizing the molecular and functional organization of the basal ganglia and their roles in health and disease.

neuroscience↗

bioRxiv2025

Neural Synchrony Links Sensorimotor Cortices in a Network for Facial Motor Control

Primate societies rely on the production and interpretation of social signals, in particular those displayed by the face. Facial movements are controlled, according to the dominant neuropsychological schema, by two separate circuits, one originating in medial frontal cortex controlling emotional expressions, and a second one originating in lateral motor and premotor areas controlling voluntary facial movements. Despite this functional dichotomy, cortical anatomy suggests that medial and lateral areas are directly connected and may thus operate as a single network. Here we test these contrasting hypotheses through structural and functional magnetic resonance imaging (fMRI) guided electrical stimulation and simultaneous multi-channel recordings from key facial motor areas in the macaque monkey brain. These areas include medial facial motor area M3 (located in the anterior cingulate cortex); two lateral face-related motor areas: M1 (primary motor) and PMv (ventrolateral premotor); and S1 (primary somatosensory cortex). Cortical responses evoked by intracortical stimulation revealed that medial and lateral areas can exert significant functional impact on each other. Simultaneous recordings of local field potentials in all facial motor areas further confirm that during facial expressions, medial and lateral facial motor areas significantly interact, primarily in the alpha and beta frequency ranges, whereas during voluntary chewing, coupling occurs at lower frequencies. These functional interactions varied across facial movement types. Thus, at the cortical level, the control of facial movements is not mediated through independent (medial/lateral) functional streams, but results from an interacting sensorimotor network. Significance StatementPrimates communicate through facial expressions. How the brain generates facial expressions remains poorly understood. To uncover how facial motor-related cortical brain regions interact to produce facial gestures, we combined fMRI-targeted electrophysiology and intracortical microstimulation while monkeys produced qualitatively different facial movements. Our two-pronged experimental approach revealed that facial motor-related cortical areas form an interconnected network characterized by synchronized neural activity demonstrating dynamic expression-selective activity states that are coordinated across the network nodes. Thus, the multiple facial motor-related cortical areas sending axons directly into the facial nucleus operate as a single network in which the overall complex, behavior-specific inter-areal interactions dictate the relevant motor output.

neuroscience↗

bioRxiv2024

Mild Hyperthermia Enhanced Liposomal Doxorubicin Delivery and CD8+ T cell Infiltration in Triple Negative Breast Cancer

Mild hyperthermia (MHTh) is often used in combination with chemotherapy and radiotherapy for cancer treatment. In the current study, the effect of MHTh on the enhanced uptake of the FDA-approved chemotherapy drug, liposomal doxorubicin (dox) in syngeneic 4T1 tumors was investigated. Doxorubicin has inherent fluorescence properties having an emission signal at 590 nm upon excitation with a 480 nm laser. A group of mice administered with doxorubicin (dox) were exposed to MHTh (42 {degrees}C) for 30 minutes whereas control group given dox did not receive MHTh. Ex vivo optical imaging of harvested tumors confirmed higher uptake of dox in treated versus the control untreated tumors. Confocal microscopy of tumor sections indicates higher fluorescent intensity due to increased accumulation of dox in MHTh-treated compared to untreated tumors. We examined the effect of MHTh to enhance CD8 tumor infiltration, production of interferon-{gamma} (IFN-{gamma}) and expression of programmed death ligand-1 (PD-L1). mRNA in situ hybridization was performed to test for transcripts of CD8, IFN-{gamma} and PD-L1. Results showed that higher expression of CD8 mRNA was observed in MHTh-administered tumors versus untreated cohorts. The signal for IFN-{gamma} and PD-L1 in both groups were not significantly different. Taken together, our findings imply that MHTh can improve tumor uptake of dox. Importantly, our data suggests that MHTh can boost CD8+ T cell infiltration.

cancer biology↗