Root exudates in mangrove forests accelerate bicarbonate production in the soil environment.

Mangrove forests are increasingly recognized as vital blue carbon ecosystems due to their high carbon sequestration capacity, primarily through the accumulation of soil organic carbon (SOC). Recent research highlights that, in addition to SOC, dissolved inorganic carbon (DIC), particularly in the form of bicarbonate (HCO₃⁻), plays a crucial role in carbon sequestration by being exported from these ecosystems to adjacent coastal waters. This study aims to investigate the previously unexamined mechanisms behind bicarbonate production in mangrove soils.

Biomass recovery of coastal young mangrove plantations in Central Thailand.

Around one-third of the world's most carbon-rich ecosystems, mangrove forests, have already been destroyed in Thailand owing to coastal development and aquaculture. Improving these degraded areas through mangrove plantations can restore various coastal ecosystem services, including CO absorption and protection against wave action. This study examines the biomass of three coastal mangrove plantations (Avicennia alba) of different ages in Samut Prakarn province, Central Thailand.

Modification of gene expression and soluble factor secretion in the lateral ventricle choroid plexus: Analysis of the impacts on the neocortical development.

The choroid plexus (ChP) is the center of soluble factor secretion into the cerebrospinal fluid in the central nervous system. It is known that various signaling factors secreted from the ChP are involved in the regulation of brain development and homeostasis. Intriguingly, the size of the ChP was prominently expanded in the brains of primates, including humans, suggesting that the expansion of the ChP contributed to mammalian brain evolution, leading to the acquisition of higher intelligence and cognitive functions.

Dual activation of Shh and Notch signaling induces dramatic enlargement of neocortical surface area.

The expansion of the neocortex represents a characteristic event over the course of mammalian evolution. Gyrencephalic mammals that have the larger brains with many folds (gyri and sulci) seem to have acquired higher intelligence, reflective of the enlargement of the neocortical surface area. In this process, germinal layers containing neural stem cells (NSCs) and neural progenitors expanded in number, leading to an increase in the total number of cortical neurons.

Sonic hedgehog expands neural stem cells in the neocortical region leading to an expanded and wrinkled neocortical surface.

An expanded and folded neocortex is characteristic of higher mammals, including humans and other primates. The neocortical surface area was dramatically enlarged during the course of mammalian brain evolution from lissencephalic to gyrencephalic mammals, and this bestowed higher cognitive functions especially to primates, including humans. In this study, we generated transgenic (Tg) mice in which the expression of Sonic hedgehog (Shh) could be controlled in neural stem cells (NSCs) and neural progenitors by using the Tet-on system.

Hes1 overexpression leads to expansion of embryonic neural stem cell pool and stem cell reservoir in the postnatal brain.

Neural stem cells (NSCs) gradually alter their characteristics during mammalian neocortical development, resulting in the production of various neurons and glial cells, and remain in the postnatal brain as a source of adult neurogenesis. Notch-Hes signaling is a key regulator of stem cell properties in the developing and postnatal brain, and Hes1 is a major effector that strongly inhibits neuronal differentiation and maintains NSCs. To manipulate Hes1 expression levels in NSCs, we generated transgenic (Tg) mice using the Tet-On system.

Hes1 expression in mature neurons in the adult mouse brain is required for normal behaviors.

Hes1 regulates the maintenance and proliferation of neural stem/progenitor cells as an essential effector of the Notch signaling pathway. Although Notch signaling is also involved in the functions of mature neurons in learning and memory and in the risk factors for mental disorders such as schizophrenia and bipolar disorder, the in-vivo role of Hes1 in mature neurons remains unknown. Here, we found that Hes1 is expressed by subsets of both excitatory and inhibitory neurons in the adult mouse brain, and that Hes1 expression is induced by neuronal stimulation.

Regulation of temporal properties of neural stem cells and transition timing of neurogenesis and gliogenesis during mammalian neocortical development.

In the developing mammalian neocortex, neural stem cells (NSCs) gradually alter their characteristics as development proceeds. NSCs initially expand the progenitor pool by symmetric proliferative division and then shift to asymmetric neurogenic division to commence neurogenesis. NSCs sequentially give rise to deep layer neurons first and superficial layer neurons later through mid- to late-embryonic stages, followed by shifting to a gliogenic phase at perinatal stages.

The proneural bHLH genes Mash1, Math3 and NeuroD are required for pituitary development.

Multiple signaling molecules and transcription factors are required for pituitary development. Activator-type bHLH genes Mash1, Math, NeuroD (Neurod) and Neurogenin (Neurog) are well known as key molecules in neural development. Although analyses of targeted mouse mutants have demonstrated involvement of these bHLH genes in pituitary development, studies with single-mutant mice could not elucidate their exact functions, because they cooperatively function and compensate each other.

Dynamic control of neural stem cells by bHLH factors.

During brain development, neural stem cells change their competency to give sequential rise to neurons and glial cells. Expression of the basic helix-loop-helix (bHLH)-type cell-fate determination factors Ascl1, Olig2, and Hes1 is oscillatory in neural stem cells. Conversely, sustained expression of these factors mediates cell-fate determination.

Hes5 regulates the transition timing of neurogenesis and gliogenesis in mammalian neocortical development.

During mammalian neocortical development, neural stem/progenitor cells (NSCs) sequentially give rise to deep layer neurons and superficial layer neurons through mid- to late-embryonic stages, shifting to gliogenic phase at perinatal stages. Previously, we found that the Hes genes inhibit neuronal differentiation and maintain NSCs. Here, we generated transgenic mice that overexpress Hes5 in NSCs of the central nervous system, and found that the transition timing from deep to superficial layer neurogenesis was shifted earlier, while gliogenesis precociously occurred in the developing neocortex of Hes5-overexpressing mice.

High salinity leads to accumulation of soil organic carbon in mangrove soil.

Although mangrove forests are one of the most well-known soil organic carbon (SOC) sinks, the mechanism underlying SOC accumulation is relatively unknown. High net primary production (NPP) along with the typical bottom-heavy biomass allocation and low soil respiration (SR) have been considered to be responsible for SOC accumulation. However, an emerging paradigm postulates that SR is severely underestimated because of the leakage of dissolved inorganic carbon (DIC) in groundwater.

Solitary cardiac metastasis of uterine cervical cancer with antemortem diagnosis: A case report and literature review.

Cardiac metastasis of uterine cervical cancer with antemortem diagnosis is extremely rare. Therefore, its landscape epidemiology has not been well elucidated to date. In the present study, a case of solitary cardiac metastasis of uterine cervical cancer diagnosed antemortem is reported, and a review of the currently available literature (which includes 18 cases of cardiac metastasis of uterine cervical cancer) is conducted.

Oscillatory control of Delta-like1 in cell interactions regulates dynamic gene expression and tissue morphogenesis.

Notch signaling regulates tissue morphogenesis through cell-cell interactions. The Notch effectors Hes1 and Hes7 are expressed in an oscillatory manner and regulate developmental processes such as neurogenesis and somitogenesis, respectively. Expression of the mRNA for the mouse Notch ligand Delta-like1 (Dll1) is also oscillatory.

Evaluation of salinity effect on quantitative analysis of aquatic humic substances using nonionic DAX-8 resin.

A nonionic macroporous resin, Amberlite(®) XAD-8, or its substitute, Supelite™ DAX-8, is used when isolating or quantifying aquatic humic substances (AHS). However, the effect of salinity on the adsorption behavior of AHS onto the resin is yet to be confirmed, rendering the possibility of salinity-induced changes in the values of quantified amounts or characteristics of AHS obtained from a salty system. To verify the results of quantification and isolation of AHS using the resin in different salinity systems, the effect of salinity on such quantitative analyses of AHS has been examined.

Hes1 and Hes5 are required for differentiation of pituicytes and formation of the neurohypophysis in pituitary development.

The pituitary gland is a critical endocrine organ regulating diverse physiological functions, including homeostasis, metabolism, reproduction, and growth. It is composed of two distinct entities: the adenohypophysis, including the anterior and intermediate lobes, and the neurohypophysis known as the posterior lobe. The neurohypophysis is composed of pituicytes (glial cells) and axons projected from hypothalamic neurons.

Hbp1 regulates the timing of neuronal differentiation during cortical development by controlling cell cycle progression.

In the developing mammalian brain, neural stem cells (NSCs) initially expand the progenitor pool by symmetric divisions. NSCs then shift from symmetric to asymmetric division and commence neurogenesis. Although the precise mechanisms regulating the developmental timing of this transition have not been fully elucidated, gradual elongation in the length of the cell cycle and coinciding accumulation of determinants that promote neuronal differentiation might function as a biological clock that regulates the onset of asymmetric division and neurogenesis.

Inversely estimating the vertical profile of the soil CO2 production rate in a deciduous broadleaf forest using a particle filtering method.

Carbon dioxide (CO2) efflux from the soil surface, which is a major source of CO2 from terrestrial ecosystems, represents the total CO2 production at all soil depths. Although many studies have estimated the vertical profile of the CO2 production rate, one of the difficulties in estimating the vertical profile is measuring diffusion coefficients of CO2 at all soil depths in a nondestructive manner. In this study, we estimated the temporal variation in the vertical profile of the CO2 production rate using a data assimilation method, the particle filtering method, in which the diffusion coefficients of CO2 were simultaneously estimated.

Hes1 and Hes5 regulate vascular remodeling and arterial specification of endothelial cells in brain vascular development.

The vascular system is the first organ to form in the developing mammalian embryo. The Notch signaling pathway is an evolutionarily conserved signaling mechanism essential for proper embryonic development in almost all vertebrate organs. The analysis of targeted mouse mutants has demonstrated essential roles of the Notch signaling pathway in embryonic vascular development.

Accelerating the tempo of the segmentation clock by reducing the number of introns in the Hes7 gene.

Periodic somite segmentation is controlled by the cyclic gene Hes7, whose oscillatory expression depends upon negative feedback with a delayed timing. The mechanism that regulates the pace of segmentation remains to be determined, but mathematical modeling has predicted that negative feedback with shorter delays would give rise to dampened but more rapid oscillations. Here, we show that reducing the number of introns within the Hes7 gene shortens the delay and results in a more rapid tempo of both Hes7 oscillation and somite segmentation, increasing the number of somites and vertebrae in the cervical and upper thoracic region.

MicroRNA9 regulates neural stem cell differentiation by controlling Hes1 expression dynamics in the developing brain.

Earlier studies show that Hes1 expression is oscillatory in neural stem cells but sustained and high in the roof plate and the floor plate, and that such different dynamics of Hes1 expression (oscillatory versus sustained) regulate different proliferation and differentiation characteristics of these cells (active in neural stem cells but rather dormant in roof/floor plate cells). The mechanism of how different dynamics of Hes1 expression is controlled remains to be determined. Here, we found that the seed sequence of microRNA-9 (miR-9) is complementary to the 3'-UTR sequence of Hes1 mRNA.

Essential roles of the histone methyltransferase ESET in the epigenetic control of neural progenitor cells during development.

In the developing brain, neural progenitor cells switch differentiation competency by changing gene expression profiles that are governed partly by epigenetic control, such as histone modification, although the precise mechanism is unknown. Here we found that ESET (Setdb1), a histone H3 Lys9 (H3K9) methyltransferase, is highly expressed at early stages of mouse brain development but downregulated over time, and that ablation of ESET leads to decreased H3K9 trimethylation and the misregulation of genes, resulting in severe brain defects and early lethality. In the mutant brain, endogenous retrotransposons were derepressed and non-neural gene expression was activated.