Immune Dysregulation in SARS-CoV-2 patients coinfected with Mycobacterium tuberculosis (Mtb) or HIV in China.

BACKGROUND: SARS-CoV-2 infections usually cause immune dysregulation in the human body. Studies of immunological changes resulting from coinfections with Mycobacterium tuberculosis (Mtb) or HIV are limited. METHODS: We conducted a retrospective study focusing on patients with COVID-19. A total of 550 patients infected with SARS-CoV-2 were enrolled in our study and categorized into four groups based on the presence of coinfections; 166 Delta-infected patients, among whom 103 patients had no coinfections, 52 who were coinfected with Mtb, 11 who were coinfected with HIV, and 384 Omicron-infected patients. By collecting data on epidemiologic information, laboratory findings, treatments, and clinical outcomes, we analyzed and compared clinical and immunological characteristics. RESULTS: Compared with those in the Delta group, the median white blood cell, CD4 + T-cell and B-cell counts were lower in the Mtb group and the HIV group. Except for those in the Omicron group, more than half of the patients in the three groups had abnormal chest CT findings. Among the three groups, there were no significant differences in any of the cytokines. Compared with those in the Delta group, the disease duration and LOS were longer in the Mtb group and the HIV group. For unvaccinated Delta-infected patients, in the Mtb and HIV groups, the number of B cells and CD4 + T cells was lower than that in the Delta group, with no significant difference in the LOS or disease duration. In the Mtb group, three (6%) patients presented with a disease duration greater than four months and had decreased lymphocyte and IL17A counts, possibly due to double infections in the lungs caused by SARS-CoV-2 and M. tuberculosis. CONCLUSIONS: We found that SARS-CoV-2 patients coinfected with Mtb or HIV exhibited a longer disease duration and longer LOS, with a decrease in B cells and CD4 + T cells, suggesting that these cells are related to immune function. Changes in cytokine levels suggest that coinfection with Mtb or HIV does not result in dysregulation of the immune response. Importantly, we discovered a chronic course of coinfection involving more than four months of Mtb and SARS-CoV-2 infection.

Land-planning management based on multiple ecosystem services and simulation in tropical forests.

Forest losses can lead to severe damage to ecosystem services (ESs), especially in the tropics. Tropical forests are widespread in southwestern China, and they experience continual effects of human activities (e.g., rubber boom). However, forest simulations of land planning have not yet been systematically conducted. Based on a future land-use simulation model, here, the spatio-temporal characteristics of four ES (i.e., soil retention, water yield, carbon fixation, and habitat quality) were examined, and three scenarios (i.e., natural development, rubber development, and ecological protection) were designed and evaluated during 2000 for Xishuangbanna (XSBN), southwestern China. The results showed that: (1) from 2000 to 2020, the average values of the ESs declined by 449.1 t for soil retention, 13.4 mm for water yield, 0.1 for habitat quality, and 0.1 kg C/m2 for carbon fixation; (2) the four ESs, with the exception of water yield, had synergistic relationships, and trade-off appeared on the margins of these synergistic relationships; (3) compared with the scenarios of natural development and rubber development, the environmental protection scenario was found to have high efficiency for protecting nature reserves and reducing fragmentation; and (4) the intensity of land-use change will accelerate the decrease of ESs, and it is essential for nature reserves and areas of northern XSBN to improve their level of environmental protection. This work not only further enriches the ES research from the ecological environment and land-planning points of view, but it also provides different planning perspectives for ES and forest scenarios. This is useful in methodical approaches to forest sustainability.

Production of Hydroxyl Radicals from Oxygenation of Simulated Acid Mine Drainage in Presence of Extracellular Polymers Substances.

The reaction mechanisms Fe(II) abiotic oxidation produce ·OH by CaCO3-induced in acid mine drainage (AMD) are well-documented, but little is known about the influence of extracellular polymeric substances (EPS) secreted by microorganisms on Fe(II) oxidation in AMD. In this study, ·OH production was experimently measured from oxygenation of simulated AMD in the presence of EPS. The cumulative ·OH increased from 56.75 to 158.70 µM within 24 h at pH 3 with the increase in EPS concentration from 0 to 12 mg/L. An appropriate pH (about 6) and EPS (6 mg/L) concentration were required for the moderate rate of Fe(II) oxidation. Besides, the yield of ·OH increased remarkably with the addition of Fe3+. In the presence of EPS, ·OH production is attributed mainly the complexation of Fe(II) with EPS, of which is rich of carboxyl and hydroxyl groups. The findings provide fundamental supplement of ·OH production from Fe(II) oxidation by microorganisms in natural AMD.

Using a grey multivariate model to predict impacts on the water quality of the Zhanghe River in China.

In order to assess the social factors affecting the water quality of the Zhanghe River and predict the potential impact of growth in primary, secondary, tertiary industries and population on water quality of the Zhanghe River in the next few years, a deformation derivative cumulative grey multiple convolution model (DGMC(1,N)) was applied. In order to improve the accuracy of the model, the accumulation of deformation derivatives is introduced, and the particle swarm optimization algorithm is used to solve the optimal order. The DGMC(1,N) model was compared with GM(1,2) and GM(1,1) models. The results show that the DGMC(1,N) model has the highest prediction accuracy. Finally, DGMC(1,N) model is used to predict the potential impact of growth in primary, secondary, tertiary industries and population on water quality in the Zhanghe River (using chemical oxygen demand (COD) as the water quality indicator).

Characterization of a non-coding RNA-associated ceRNA network in metastatic lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is a highly malignant cancer. Although competing endogenous RNA (ceRNA)-based profiling has been investigated in patients with LUAD, it has not been specifically used to study metastasis in LUAD. We found 130 differentially expressed (DE) lncRNAs, 32 DE miRNAs and 981 DE mRNAs from patients with LUAD in The Cancer Genome Atlas (TCGA) database. We analysed the functions and pathways of 981 DE mRNAs using the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Based on the target DE mRNAs and DE lncRNAs of DE miRNAs, we established an lncRNA-miRNA-mRNA ceRNA network, comprising 37 DE lncRNAs, 22 DE miRNAs and 212 DE mRNAs. Subsequently, we constructed a protein-protein interaction network of DE mRNAs in the ceRNA network. Among all, DE RNAs, 5 DE lncRNAs, 5 DE miRNAs and 45 DE mRNAs were confirmed found to be associated with clinical prognosis. Moreover, 3 DE lncRNAs, 4 DE miRNAs and 9 DE mRNAs in the ceRNA network were associated with clinical prognosis. We further screened 3 DE lncRNAs, 3 DE miRNAs and 3 DE mRNAs using clinical samples. These DE lncRNAs, DE miRNAs and DE mRNAs in ceRNA network may serve as independent biomarkers of LUAD metastasis.

Insufficient CD100 shedding contributes to suppression of CD8+ T-cell activity in non-small cell lung cancer.

CD100 is an immune semaphorin constitutively expressed on T-cells. Matrix metalloproteinase (MMP) is an important mediator of membrane-bound CD100 (mCD100) cleavage to generate soluble CD100 (sCD100), which has immunoregulatory activity in immune cell responses. The aim of the study was to investigate the level and role of sCD100 and mCD100 in modulating CD8+ T-cell function in non-small cell lung cancer (NSCLC). sCD100 and MMP-14 levels in the serum and bronchoalveolar lavage fluid (BALF), and mCD100 expression on peripheral and lung-resident CD8+ T-cells were analysed in NSCLC patients. The ability to induce sCD100 and the effect of MMP-14 on mCD100 shedding for the regulation of non-cytolytic and cytolytic functions of CD8+ T-cells were also analysed in direct and indirect contact co-culture systems. NSCLC patients had lower serum sCD100 and higher mCD100 levels on CD8+ T-cells compared with healthy controls. BALF from the tumour site also had decreased sCD100 and increased mCD100 on CD8+ T-cells compared with the non-tumour site. Recombinant CD100 stimulation enhanced non-cytolytic and cytolytic functions of CD8+ T-cells from NSCLC patients, whereas blockade of CD100 receptor CD72 attenuated CD8+ T-cell activity. NSCLC patients had lower MMP-14 in the serum and in BALF from the tumour site. Recombinant MMP-14 mediated mCD100 shedding from CD8+ T-cell membrane, and led to promotion of CD8+ T-cell response in NSCLC patients. Overall, decreased MMP-14 resulted in insufficient CD100 shedding, leading to suppression of peripheral and lung-resident CD8+ T-cell activity in NSCLC.

Loss of IP3 Receptor-Mediated Ca2+ Release in Mouse B Cells Results in Abnormal B Cell Development and Function.

Intracellular calcium (Ca2+) mobilization after engagement of the BCR has been proposed to play an important role in B cell development and function. BCR activation causes an initial Ca2+ release from the endoplasmic reticulum that is mediated by inositol 1,4,5-trisphosphate receptor (IP3R) and then triggers store-operated Ca2+ entry once endoplasmic reticulum Ca2+ store is depleted. Store-operated Ca2+ entry has been shown to regulate B cell function but is dispensable for B cell development. By contrast, the function of IP3R-mediated Ca2+ release in B cells remains to be determined. In this study, we generated a B cell-specific IP3R triple-knockout (IP3R-TKO) mouse model and revealed that loss of IP3Rs increased transitional B cell numbers and reduced recirculating mature B cell numbers in bone marrow. In the peripheral tissues, the numbers of conventional B2 B cells and B1 B cells were both significantly decreased in IP3R-TKO mice. Ablation of IP3Rs also dramatically reduced BCR-mediated B cell proliferation and survival. Furthermore, T cell-dependent and T cell-independent Ab responses were altered in IP3R-TKO mice. In addition, deletion of IP3Rs reduced IL-10-producing regulatory B cell numbers and led to defects in NFAT activation, which together resulted in decreased IL-10 secretion. Taken together, our study demonstrated for the first time, to our knowledge, that IP3R-mediated Ca2+ release plays an essential role in regulating B cell development, proliferation, Ab production, and B cell regulatory function in vivo.

Interleukin-35 Suppresses the Antitumor Activity of T Cells in Patients with Non-Small Cell Lung Cancer.

BACKGROUND/AIMS: Interleukin (IL)-35 has immunosuppressive functions in autoimmune diseases, infectious diseases, and certain cancers. However, few studies have focused on its immunoregulatory activity in non-small cell lung cancer (NSCLC). Thus, we investigated the role of IL-35 in the pathogenesis of this disease. METHODS: A total of 66 NSCLC patients and 21 healthy individuals were enrolled. IL-35 expression in peripheral blood and bronchoalveolar lavage fluid (BALF) was measured. The modulatory functions of IL-35 on purified CD4+ and CD8+ T cells from NSCLC patients were investigated in direct and indirect coculture systems with NSCLC cell lines. RESULTS: IL-35 expression was significantly increased in BALF from the tumor site, but not in the peripheral blood of NSCLC patients. IL-35 did not affect the bioactivity including proliferation, cytokine production, cell cycle, and cellular invasion of NSCLC cells. It suppressed responses from type 1 T helper (Th1) and Th17 cells but elevated the regulatory T cell response in cultured CD4+ T cells from NSCLC patients, and reduced cytokine-mediated CD4+ T cells cytotoxicity to NSCLC cells. Moreover, IL-35 also inhibited cytotoxic gene expression in CD8+ T cells from NSCLC, reducing their cytolytic and noncytolytic functions. CONCLUSION: The results of this study suggest that IL-35 contributes to the dysfunction/exhaustion of T cells and limited antitumor immune responses in NSCLC.

Tuning the Outward to Inward Swelling in Lithiated Silicon Nanotubes via Surface Oxide Coating.

Electrochemically induced mechanical degradation hinders the application of Si anodes in advanced lithium-ion batteries. Hollow structures and surface coatings have been often used to mitigate the degradation of Si-based anodes. However, the structural change and degradation mechanism during lithiation/delithiation of hollow Si structures with coatings remain unclear. Here, we combine in situ TEM experiment and chemomechanical modeling to study the electrochemically induced swelling of amorphous-Si (a-Si) nanotubes with different thicknesses of surface SiOx layers. Surprisingly, we find that no inward expansion occurs at the inner surface during lithiation of a-Si nanotubes with native oxides. In contrast, inward expansion can be induced by increasing the thickness of SiOx on the outer surface, thus reducing the overall outward swelling of the lithiated nanotube. Moreover, both the sandwich lithiation mechanism and the two-stage lithiation process in a-Si nanotubes remain unchanged with the increasing thickness of surface coatings. Our chemomechanical modeling reveals the mechanical confinement effects in lithiated a-Si nanotubes with and without SiOx coatings. This work not only provides insights into the degradation of nanotube anodes with surface coatings but also sheds light onto the optimal design of hollow anodes for high-performance lithium-ion batteries.

Griffith criterion for brittle fracture in graphene.

There are prevailing concerns with the critical dimensions when conventional theories break down. Here we find that the Griffith criterion remains valid for cracks down to 10 nm but overestimates the strength of shorter cracks. We observe the preferred crack extension along the zigzag edge in graphene, and explain this phenomenon by local strength-based failure rather than energy-based Griffith criterion. These results provide a mechanistic basis for reliable applications of graphene in miniaturized devices and nanocomposites.

In situ transmission electron microscopy study of electrochemical sodiation and potassiation of carbon nanofibers.

Carbonaceous materials have great potential for applications as anodes of alkali-metal ion batteries, such as Na-ion batteries and K-ion batteries (NIB and KIBs). We conduct an in situ study of the electrochemically driven sodiation and potassiation of individual carbon nanofibers (CNFs) by transmission electron microscopy (TEM). The CNFs are hollow and consist of a bilayer wall with an outer layer of disordered-carbon (d-C) enclosing an inner layer of crystalline-carbon (c-C). The d-C exhibits about three times volume expansion of the c-C after full sodiation or potassiation, thus suggesting a much higher storage capacity of Na or K ions in d-C than c-C. For the bilayer CNF-based electrode, a steady sodium capacity of 245 mAh/g is measured with a Coulombic efficiency approaching 98% after a few initial cycles. The in situ TEM experiments also reveal the mechanical degradation of CNFs through formation of longitudinal cracks near the c-C/d-C interface during sodiation and potassiation. Geometrical changes of the tube are explained by a chemomechanical model using the anisotropic sodiation/potassiation strains in c-C and d-C. Our results provide mechanistic insights into the electrochemical reaction, microstructure evolution and mechanical degradation of carbon-based anodes during sodiation and potassiation, shedding light onto the development of carbon-based electrodes for NIBs and KIBs.

Nanovoid formation and annihilation in gallium nanodroplets under lithiation-delithiation cycling.

The irreversible chemomechanical degradation is a critical issue in the development of high-capacity electrode materials for the next-generation lithium (Li)-ion batteries. Here we report the self-healing behavior of gallium nanodroplets (GaNDs) under electrochemical cycling at room temperature, observed with in situ transmission electron microscopy (TEM). During lithiation, the GaNDs underwent a liquid-to-solid phase transition, forming a crystalline phase (LixGa) with ~160% volume expansion. Owing to the uneven Li flow during lithiation, the fully lithiated GaNDs exhibited highly distorted morphologies. Upon delithiation, the reverse phase transition occurred, accompanied with the nucleation and growth of a nanosized void. After the GaNDs were fully delithiated, the nanovoid gradually annihilated. Our analysis, along with phase field modeling and experimental measurements of the void growth and annihilation, provides mechanistic insights into the void formation and annihilation mechanism. The GaNDs may function as an effective healing agent in durable composite electrodes for high-performance Li-ion batteries, wherein active components, such as Si, are susceptible to fracture.

Two-phase electrochemical lithiation in amorphous silicon.

Lithium-ion batteries have revolutionized portable electronics and will be a key to electrifying transport vehicles and delivering renewable electricity. Amorphous silicon (a-Si) is being intensively studied as a high-capacity anode material for next-generation lithium-ion batteries. Its lithiation has been widely thought to occur through a single-phase mechanism with gentle Li profiles, thus offering a significant potential for mitigating pulverization and capacity fade. Here, we discover a surprising two-phase process of electrochemical lithiation in a-Si by using in situ transmission electron microscopy. The lithiation occurs by the movement of a sharp phase boundary between the a-Si reactant and an amorphous Li(x)Si (a-Li(x)Si, x ~ 2.5) product. Such a striking amorphous-amorphous interface exists until the remaining a-Si is consumed. Then a second step of lithiation sets in without a visible interface, resulting in the final product of a-Li(x)Si (x ~ 3.75). We show that the two-phase lithiation can be the fundamental mechanism underpinning the anomalous morphological change of microfabricated a-Si electrodes, i.e., from a disk shape to a dome shape. Our results represent a significant step toward the understanding of the electrochemically driven reaction and degradation in amorphous materials, which is critical to the development of microstructurally stable electrodes for high-performance lithium-ion batteries.

Investigation of the migration of natural organic matter-iron-antimony nano-colloids in acid mine drainage.

Colloids can potentially affect the efficacy of traditional acid mine drainage (AMD) treatment methods such as precipitation and filtration. However, it is unclear how colloids affect antimony (Sb) migration in AMD, especially when natural organic matter (NOM) is present. To conduct an in-depth investigation on the formation and migration behavior of NOM, iron (Fe), Sb and NOM-Fe-Sb colloids in AMD, experiments were performed under simulated AMD conditions. The results demonstrate significant variations in the formation of NOM-Fe-Sb colloids (1-3-450 nm) as the molar ratio of carbon to iron (C/Fe) increases within acidic conditions (pH = 3). Increasing the C/Fe molar ratio from 0.1 to 1.2 resulted in a decrease in colloid formation but an increase in particulate fraction. The distribution of colloidal Sb, Sb(III), and Fe(III) within the NOM-Fe-Sb colloids decreased from 68 % to 55 %, 72 % to 57 %, and 68 % to 55 %, respectively. Their distribution in the particulate fraction increased from 28 % to 42 %, 21 % to 34 %, and 8 % to 27 %. XRD, FTIR, and SEM-EDS analyses demonstrated that NOM facilitates the formation and crystallization of Fe3O4 and FeSbO4 crystalline phases. The formation of the colloids depended on pH. Our results indicate that NOM-Fe-Sb colloids can form when the pH ≤ 4, and the proportion of colloidal Sb fraction within the NOM-Fe-Sb colloids increased from 9 % to a maximum of 73 %. Column experiments show that the concentration of NOM-Fe-Sb colloids reaches its peak and remains stable at approximately 3.5 pore volumes (PVs), facilitating the migration of Sb in the porous media. At pH ≥ 5, stable NOM-Fe-Sb colloids do not form, and the proportion of colloidal Sb fraction decreases from 7 % to 0 %. This implies that as pH increases, the electrostatic repulsion between colloidal particles weakens, resulting in a reduction in the colloidal fraction and an increase in the particulate fraction. At higher pH values (pH ≥ 5), the repulsive forces between colloidal particles nearly disappear, promoting particle aggregation. The findings of this study provide important scientific evidence for understanding the migration behavior of NOM-Fe-Sb colloids in AMD. As the pH gradually shifts from acidic to near-neutral pH during the remediation process of AMD, these results could be applied to develop new strategies for this purpose.

Engineering a Low-Strain Si@TiSi2@NC Composite for High-Performance Lithium-Ion Batteries.

The huge volume expansion/contraction of silicon (Si) during the lithium (Li) insertion/extraction process, which can lead to cracking and pulverization, poses a substantial impediment to its practical implementation in lithium-ion batteries (LIBs). The development of low-strain Si-based composite materials is imperative to address the challenges associated with Si anodes. In this study, we have engineered a TiSi2 interface on the surface of Si particles via a high-temperature calcination process, followed by the introduction of an outermost carbon (C) shell, leading to the construction of a low-strain and highly stable Si@TiSi2@NC composite. The robust TiSi2 interface not only enhances electrical and ionic transport but also, more critically, significantly mitigates particle cracking by restraining the stress/strain induced by volumetric variations, thus alleviating pulverization during the lithiation/delithiation process. As a result, the as-fabricated Si@TiSi2@NC electrode exhibits a high initial reversible capacity (2172.7 mAh g-1 at 0.2 A g-1), superior rate performance (1198.4 mAh g-1 at 2.0 A g-1), and excellent long-term cycling stability (847.0 mAh g-1 after 1000 cycles at 2.0 A g-1). Upon pairing with LiNi0.6Co0.2Mn0.2O2 (NCM622), the assembled Si@TiSi2@NC||NCM622 pouch-type full cell exhibits exceptional cycling stability, retaining 90.1% of its capacity after 160 cycles at 0.5 C.

Prenatal progesterone treatment modulates fetal brain transcriptome and impacts adult offspring behavior in mice.

Maternal exposure to elevated levels of steroid hormones during pregnancy is associated with the development of chronic conditions in offspring that manifest in adulthood. However, the effects of progesterone (P4) administration during early pregnancy on fetal development and subsequent offspring behavior remain poorly understood. In this study, we aimed to investigate the effects of P4 treatment during early pregnancy on the transcript abundance in the fetal brain and assess the behavioral consequences in the offspring during adolescence and adulthood. Using RNA-seq analysis, we examined the impact of P4 treatment on the fetal brain transcriptome in a dosage-dependent manner. Our results revealed differential regulation of genes involved in neurotransmitter transport, synaptic transmission, and transcriptional regulation. Specifically, we observed bidirectional regulation of transcription factors (TFs) by P4 at different doses, highlighting the critical role of these TFs in neurodevelopment. To assess behavioral outcomes, we conducted open field and elevated plus maze tests. Offspring treated with low-dose P4 (LP4) displayed increased exploratory behavior during both adolescence and adulthood. In contrast, the high-dose P4 (HP4) group exhibited impaired exploration and heightened anxiety-like behaviors compared to the control mice. Moreover, in a novel object recognition test, HP4-treated offspring demonstrated impaired object recognition memory during both developmental stages. Additionally, both LP4 and HP4 groups showed reduced social interaction in the three-chamber test. These results suggest that prenatal exposure to P4 exerts a notable influence on the expression of genes associated with neurodevelopment and may induce alterations in behavioral characteristics in progeny, highlighting the need to monitor progesterone levels during pregnancy for long-term impacts on fetal brain development and behavior.

Early statin exposure influences cardiac and skeletal development with implications for ion channel transcriptomes in zebrafish.

Statins, widely prescribed for cholesterol management by inhibiting HMG-CoA reductase in the cholesterol biosynthesis pathway, may also influence vertebrate development. In this study, we investigated the developmental effects of two widely used statins, atorvastatin (ATO) and pravastatin (PRA), on zebrafish offspring. For ATO, we administered doses classified as low (1 µM), medium (5 µM), and high (10 µM), while for PRA, the corresponding concentrations were set at low (18 µM), medium (180 µM), and high (270 µM). Our results showed significant reductions in birth and hatching rates, along with decreased body length in offspring at all ATO concentrations and medium to high PRA concentrations. A notable increase in malformation rates, especially in the spine and heart, was observed across all ATO treatments and in medium and high PRA groups. Additionally, we observed reduced heart contraction rates, decreased heart size, lower bone volumes, and diminished expression of mRNA osteogenic markers. Elevated venous sinus-artery bulb (SV-BA) ratios, increased thoracic area, and abnormal cartilage development were also prominent in all ATO-treated groups. Transcriptome analysis revealed alterations in genes predominantly associated with ion channels. These findings provide insights into the potential impacts of specific concentrations of statins on offspring development and highlight potential gene interactions with statins.

Orientation-dependent interfacial mobility governs the anisotropic swelling in lithiated silicon nanowires.

Recent independent experiments demonstrated that the lithiation-induced volume expansion in silicon nanowires, nanopillars, and microslabs is highly anisotropic, with predominant expansion along the <110> direction but negligibly small expansion along the <111> direction. The origin of such anisotropic behavior remains elusive. Here, we develop a chemomechanical model to study the phase evolution and morphological changes in lithiated silicon nanowires. The model couples the diffusive reaction of lithium with the lithiation-induced elasto-plastic deformation. We show that the apparent anisotropic swelling is critically controlled by the orientation-dependent mobility of the core-shell interface, i.e., the lithiation reaction rate at the atomically sharp phase boundary between the crystalline core and the amorphous shell. Our results also underscore the importance of structural relaxation by plastic flow behind the moving phase boundary, which is essential to quantitative prediction of the experimentally observed morphologies of lithiated silicon nanowires. The study sheds light on the lithiation-mediated failure in nanowire-based electrodes, and the modeling framework provides a basis for simulating the morphological evolution, stress generation, and fracture in high-capacity electrodes for the next-generation lithium-ion batteries.

Inter-examiner and intra-examiner reliability of optical coherence tomography angiography in vascular density measurement of retinal and choriocapillaris plexuses in healthy children aged 6-15 years.

Objective: This study aimed to test the inter-examiner and intra-examiner reliability of macular vascular density (VD) measurement of retinal and choriocapillaris plexuses in healthy children using optical coherence tomography angiography (OCTA). Materials and methods: Ninety-two school children were prospectively recruited. Macular OCTA images (6 × 6 mm2) were obtained thrice by two examiners using the RTVue-XR Avanti OCT system. The coefficient of variation (COV), intraclass correlation coefficient (ICC), and Bland-Altman plots were used to evaluate the repeatability and reproducibility. Results: Ninety participants aged 6-15 years were enrolled; two participants were excluded because of low-quality images. In the retina, the reproducibility and repeatability of VD became poorer from superficial to deep retinal capillary plexus (superficial: COV = 4.61-11.11%; intermediate: COV = 7.73-14.15%; deep: COV = 14.60-32.28%). For both reproducibility and repeatability, the ICC ranged from moderate to high (superficial plexus: ICC = 0.570-0.976; intermediate plexus: ICC = 0.720-0.968; deep plexus: ICC = 0.628-0.954). In the choroid, the inter-examiner reproducibility and intra-examiner repeatability of the VD measurement of choriocapillaris were excellent in the macula, fovea, parafovea, and perifovea (COV = 1.00-6.10%; ICC = 0.856-0.950). The parameters of the foveal avascular zone (FAZ) also showed significant reproducibility and repeatability (COV = 0.01-0.21%; ICC = 0.743-0.994). Conclusion: The VD measurements of the choriocapillaris and FAZ parameters using OCTA showed excellent inter-examiner and intra-examiner reliability in school children. The reproducibility and repeatability of the VD of three retinal capillary plexuses depended on the depth of the retinal capillary plexus.

Acoustically accelerated neural differentiation of human embryonic stem cells.

Human embryonic stem cells (hESCs) and their derived products offer great promise for targeted therapies and drug screening, however, the hESC differentiation process of mature neurons is a lengthy process. To accelerate the neuron production, an acoustic stimulator producing surface acoustic waves (SAWs) is proposed and realized by clamping a flexible printed circuit board (PCB) directly onto a piezoelectric substrate. Neural differentiation of the hESCs is greatly accelerated after application of the acoustic stimulations. Acceleration mechanisms for neural differentiation have been explored by bulk RNA sequencing, quantitative polymerase chain reaction (qPCR) and immunostaining. The RNA sequencing results show changes of extracellular matrix-related and physiological activity-related gene expression in the low or medium SAW dose group and the high SAW dose group, respectively. The neural progenitor cell markers, including Pax6, Sox1, Sox2, Sox10 and Nkx2-1, are less expressed in the SAW dose groups compared with the control group by the qPCR. Other genes including Alk, Cenpf, Pcdh17, and Actn3 are also found to be regulated by the acoustic stimulation. Moreover, the immunostaining confirmed that more mature neuron marker Tuj1-positive cells, while less stem cell marker Sox2-positive cells, are presented in the SAW dose groups. These results indicate that the SAW stimulation accelerated neural differentiation process. The acoustic stimulator fabricated by using the PCB is a promising tool in regulation of stem cell differentiation process applied in cell therapy. STATEMENT OF SIGNIFICANCE: Human embryonic stem cells (hESC) are used for investigating the complex mechanisms involved in the development of specialized biological cells and organs. Different types of hESCs derived cell products can be used for cell therapy procedures aiming to regenerate functional tissues in patients who suffer from various degenerative diseases. Accelerating the hESCs' differentiation process can considerably benefit the clinical utilization of these cells. This study develops a highly effective acoustic stimulator working at ∼20 MHz to investigate what roles do acousto-mechanical stimuli play in the differentiation of hESCs. Our results show that acoustic dose alters the extracellular matrix and physiological activity-related gene expression, which indicates that the acoustic stimulation is an important tool for regulating the stem cells' differentiation processes in cell therapy.