Cellular anatomy and physiology

Although the hippocampus is one of the most-studied brain regions in mammals, research on the avian hippocampus has been more limited in scope. It is generally agreed that the hippocampus is an ancient feature of the amniote brain, and therefore homologous between the two lineages. Because birds and mammals are evolutionarily not very closely related, any shared anatomy is likely to be crucial for shared functions of their hippocampi. These functions, in turn, are likely to be essential if they have been conserved for over 300 million years...

Coping with water stress depends on maintaining cellular function and hydraulic conductance. Yet measurements of vulnerability to drought and salinity do not often focus on capacitance in branch organs that buffer hydraulic function during water stress. The relationships between branch water relations, stem hydraulic vulnerability and stem anatomy were investigated in two co-occurring mangroves Aegiceras corniculatum and Rhizophora stylosa growing at low and high salinity. The dynamics of branch water release acted to conserve water content in the stem at the expense of the foliage during extended drying...

The blood-brain barrier (BBB) is a key physiological component of the central nervous system (CNS), maintaining nutrients, clearing waste, and protecting the brain from pathogens. The inherent barrier properties of the BBB pose a challenge for therapeutic drug delivery into the CNS to treat neurological diseases. Impaired BBB function has been related to neurological disease. Cerebral amyloid angiopathy (CAA), the deposition of amyloid in the cerebral vasculature leading to a compromised BBB, is a co-morbidity in most cases of Alzheimer's disease (AD), suggesting that BBB dysfunction or breakdown may be involved in neurodegeneration...

The development of fleshy fruits involves changes in size and mass, followed by cell differentiation, which is associated with anatomical and histological changes. Parallel to these changes, metabolic alterations lead to the production of osmolytes and energy that modify cell turgor pressure, thereby promoting cell expansion and fruit growth. Detailed information is known about these processes in climacteric fruits (e.g. tomato); however, the regulation of metabolism and its association with anatomical changes in non-climacteric fruit development are poorly understood...

CD4+ T cells have orchestrated and regulated immunity since the introduction of jawed vertebrates, yet our understanding of CD4+ T cell evolution, development, and cellular physiology has only begun to be unearthed in the past few decades. Discoveries of genetic diseases that ablate this cellular population have provided insight into their critical functions while transcriptomics, proteomics, and high-resolution microscopy have recently revealed new insights into CD4+ T cell anatomy and physiology. This article compiles historical, microscopic, and multi-omics data that can be used as a reference atlas and index to dissect cellular physiology within these influential cells and further understand pathologies like HIV infection that inflict human CD4+ T cells...

Leptomeninges, consisting of the pia mater and arachnoid, form a connective tissue investment and barrier enclosure of the brain. The exact nature of leptomeningeal cells has long been debated. In this study, we identify five molecularly distinct fibroblast-like transcriptomes in cerebral leptomeninges; link them to anatomically distinct cell types of the pia, inner arachnoid, outer arachnoid barrier, and dural border layer; and contrast them to a sixth fibroblast-like transcriptome present in the choroid plexus and median eminence...

The spatial anatomy of hematopoiesis in bone marrow has been extensively studied in mice and other preclinical models, but technical challenges have precluded a commensurate exploration in humans. Institutional pathology archives contain thousands of paraffinized bone marrow core biopsy tissue specimens, providing a rich resource for studying the intact human bone marrow topography in a variety of physiologic states. Thus, we developed an end-to-end pipeline involving multiparameter whole tissue staining, in situ imaging at single-cell resolution, and artificial intelligence (AI)-based digital Whole Slide Image (WSI) analysis, and then applied it to a cohort of disease-free samples to survey alterations in the hematopoietic topography associated with aging...

Inositol is a unique biological small molecule that can be phosphorylated or even further pyrophosphorylated on each of its six hydroxyl groups. These numerous phosphorylation states of inositol along with the kinases and phosphatases that interconvert them comprise the inositol phosphate signaling pathway. Inositol hexakisphosphate kinases, or IP6Ks, convert the fully mono-phosphorylated inositol to the pyrophosphate 5-IP7 (also denoted IP7). There are three isoforms of IP6K: IP6K1, 2, and 3. Decades of work have established a central role for IP6Ks in cell signaling...

The extracellular matrix (ECM) is a complex, hierarchical material containing structural and bioactive components. This complexity makes decoupling the effects of biomechanical properties and cell-matrix interactions difficult, especially when studying cellular processes in a 3D environment. Matrix mechanics and cell adhesion are both known regulators of specific cellular processes such as stem cell proliferation and differentiation. However, more information is required about how such variables impact various neural lineages that could, upon transplantation, therapeutically improve neural function after central nervous system (CNS) injury or disease...

For over three centuries, hydrogen sulfide (H2 S) has been known as a toxic and deadly gas at high concentrations, with a distinctive smell of rotten eggs. However, studies over the past two decades have shown that H2 S has risen above its historically notorious label and has now received significant scientific attention as an endogenously produced gaseous signaling molecule that participates in cellular homeostasis and influences a myriad of physiological and pathological processes at low concentrations. Its endogenous production is enzymatically regulated, and when dysregulated, contributes to pathogenesis of renal diseases...

Cells must access resources to survive, and the anatomy of multicellular structures influences this access. In diverse multicellular eukaryotes, resources are provided by internal conduits that allow substances to travel more readily through tissue than they would via diffusion. Microbes growing in multicellular structures, called biofilms, are also affected by differential access to resources and we hypothesized that this is influenced by the physical arrangement of the cells. In this study, we examined the microanatomy of biofilms formed by the pathogenic bacterium Pseudomonas aeruginosa and discovered that clonal cells form striations that are packed lengthwise across most of a mature biofilm's depth...

The Subthalamic Nucleus (STh) is a lens-shaped subcortical structure located ventrally to the thalamus, that despite being embryologically derived from the diencephalon, is functionally implicated in the basal ganglia circuits. Because of this strict structural and functional relationship with the circuits of the basal ganglia, the STh is a current target for deep brain stimulation, a neurosurgical procedure employed to alleviate symptoms in movement disorders, such as Parkinson's disease and dystonia. However, despite the great relevance of this structure for both basal ganglia physiology and pathology, the neurochemical and molecular anatomy of the STh remains largely unknown...

Understanding the complexities of the human brain and its associated disorders poses a significant challenge in neuroscience. Traditional research methods have limitations in replicating its intricacies, necessitating the development of in vitro models that can simulate its structure and function. Three-dimensional in vitro models, including organoids, cerebral organoids, bioprinted brain models, and functionalized brain organoids, offer promising platforms for studying human brain development, physiology, and disease...

Osteoarthritis (OA) is a degenerative joint disease marked by cartilage degradation and loss of function. Recently, there have been increased efforts to attenuate and reverse OA by stimulating cartilage regeneration and preventing cartilage degradation. Human placental extract (HPE) may be an option due to its anti-inflammatory, antioxidant, and growth stimulatory properties. These properties are useful in preventing cell death and senescence, which may optimize in-situ cartilage regeneration. In this review, we discuss the anatomy and physiology of the placenta, as well as explore in vivo and in vitro studies assessing its effects on tissue regeneration...

The time since death is an important aspect of forensic medicine; however, there is not an accurate single method to determine this data. Therefore, this research aimed to evaluate parameters and procedures based on the morphological analysis of cells and tissues to determine the time since death, using animal models. Pigs were chosen in this research because of their similarities with human anatomy, physiology, and pathophysiology. We identified the cells and tissue alterations in the viscera of pig cadavers according to the time since death, also describing the changes in the temperature of the organs and the bodies...

Blood barriers serve as key points of transport for essential molecules as well as lines of defense to protect against toxins. In vitro modeling of these barriers is common practice in the study of their physiology and related diseases. This review describes a common method of using an adaptable, low cost, semipermeable, suspended membrane to experimentally model three blood barriers in the human body: the blood-brain barrier (BBB), the gut-blood barrier (GBB), and the air-blood barrier (ABB). The GBB and ABB both protect from the outside environment, while the BBB protects the central nervous system from potential neurotoxic agents in the blood...

Seeds are an indispensable part of the flowering plant life cycle and a critical determinant of agricultural production. Distinct differences in the anatomy and morphology of seeds separate monocots and dicots. Although some progress has been made with respect to understanding seed development in Arabidopsis , the transcriptomic features of monocotyledon seeds at the cellular level are much less understood. Since most important cereal crops, such as rice, maize, and wheat, are monocots, it is essential to study transcriptional differentiation and heterogeneity during seed development at a finer scale...

AIMS: Diabetic retinopathy (DR) is a common complication of diabetes that causes visual impairment and blindness in adults. This study aimed to explore the protective effects of n-Butylidenephthalide (BP) on hyperglycemia-treated RPE in vitro and in vivo. MAIN METHODS: C57BL/6 mice were injected with STZ by intraperitoneal to induce early DR and orally administrated with 2 mg/kg BP every day for twelve weeks. Body weight and blood glucose were measured once a week...

Adaptations occur at many levels, for example, from DNA sequence of regulatory elements and cellular homeostatic systems to organismal physiology and behaviour (Mayr, 1997). Established adaptations are maintained by purifying and stabilizing selection. Students of animal diversity tend to focus on higher order traits, anatomy, physiology, organismal function and interactions. The core cellular and metabolic systems of metazoans evolved early in their history and are assumed to be rather similar between groups...

At present, the knowledge base on characteristics and biology of spermatogonia in livestock is limited in comparison to rodents, yet the importance of studying these cells for comparative species analysis and enhancing reproductive capacity in food animals is high. Previous studies have established that although many core attributes of organ physiology and mechanisms governing essential cellular functions are conserved across eutherians, significant differences exist between mice and higher order mammals. In this chapter, we briefly discuss distinguishing aspects of testicular anatomy and the spermatogenic lineage in livestock and critical considerations for studying spermatogonial stem cell biology in these species...