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The analysis of pineal cell biology has undergone remarkable development as techniques have become available which allow for sequencing of entire transcriptomes and, most recently, the sequencing of the transcriptome of individual cells. Identification of at least nine distinct cell types in the rat pineal gland has been made possible, allowing identification of the precise cells of origin and expression of transcripts for the first time. Here the history and current state of knowledge generated by these transcriptomic efforts is reviewed, with emphasis on the insights suggested by the findings.

Chemical kinetics is a branch of physical chemistry that constitutes an essential part of undergraduate education. In general, a complex and expensive experimental apparatus is indispensable for observing the kinetics of a chemical process owing to the continuity of chemical reactions. Thus, intuitive visualization of the chemical kinetics using a simple experimental apparatus is challenging. Herein, a portable flow reactor was designed and used to observe the chemical kinetics of a first-order process. Continuous chemical reactions were visualized via the flow reactor as static patterns with color gradients. The thermochromism of the rhodamine B salicylaldehyde hydrazone zinc(II) complex was visualized via the flow reactor and found to follow first-order kinetics. The color gradients of static reaction patterns were analyzed by comparing them with standard color cards, and the kinetic parameters, such as the reaction rate constants at different temperatures and the activation energy, were determined. By performing this experiment, students can learn about flow chemistry, photochromism, and thermochromism. The interesting experimental process and distinct color changes can hold the students' attention. The two calculation methods can help the students better understand the rate equation of a first-order reaction. The experimental apparatus is low cost and commercially available, which is beneficial for the widespread use of this experiment.

Background Kallistatin exerts beneficial effects on organ injury by inhibiting oxidative stress and inflammation. However, the role of kallistatin in atherosclerosis is largely unknown. Here, we investigated the role and mechanisms of kallistatin in patients with coronary artery disease (CAD), atherosclerotic plaques of apoE−/− mice, and endothelial activation. Methods and Results Plasma kallistatin levels were analyzed in 453 patients at different stages of CAD. Kallistatin levels were significantly lower in patients with CAD and negatively associated with CAD severity and oxidative stress. Human kallistatin cDNA in an adenoviral vector was injected intravenously into apoE−/− mice after partial carotid ligation, with or without nitric oxide synthase inhibitor (Nω‐nitro‐L‐arginine methyl ester) or sirtuin 1 inhibitor (nicotinamide). Kallistatin gene delivery significantly reduced macrophage deposition, oxidative stress, and plaque volume in the carotid artery, compared with control adenoviral injection. Kallistatin administration increased endothelial nitrous oxide synthase, sirtuin 1, interleukin‐10, superoxide dismutase 2, and catalase expression in carotid plaques. The beneficial effects of kallistatin in mice were mitigated by Nω‐nitro‐L‐arginine methyl ester or nicotinamide. Furthermore, human kallistatin protein suppressed tumor necrosis factor‐α–induced NADPH oxidase activity and increased endothelial nitrous oxide synthase and sirtuin 1 expression in cultured human endothelial cells. These effects were also abolished by Nω‐nitro‐L‐arginine methyl ester or nicotinamide. Conclusions This was the first study to demonstrate that reduced plasma kallistatin levels in patients are associated with CAD severity and oxidative stress. Kallistatin treatment prevents carotid atherosclerotic plaque formation in mice by stimulating the sirtuin 1/endothelial nitrous oxide synthase pathway. These findings indicate the potential protective effects of kallistatin on atherosclerosis in human subjects and mouse models.

Circular RNAs (circRNAs) are a recently identified class of noncoding RNAs that participate in several physiological processes. However, the expression of circRNAs in infantile hemangioma (IH) remains unknown.The profile of circRNAs was assessed by microarray in four pairs of IH and adjacent skin tissues. The expression of circRNAs was validated by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Furthermore, circRNA-microRNAs (miRNA)-mRNA networks were constructed using bioinformatics tools.234 up- and 374 down- regulated circRNAs were identified in IH by microarray. Among them, the expression of two up-regulated circRNAs (hsa_circRNA_100933 and hsa_circRNA_100709) and one down-regulated circRNA (hsa_circRNA_104310) was confirmed by qRT-PCR. In addition, 3,019 miRNA response elements (MREs) of circRNAs were predicted, and two circRNA-miRNA-mRNA networks were constructed, including 100 and 94 target genes of hsa_circRNA_100933 and hsa_circRNA_104310, respectively. GO and pathway analysis showed that both networks participated in angiogenesis and vascular development-related biological processes.This is the first study to reveal the profiling of circRNAs in IH and pave the way for further characterization of the role of circRNAs in the pathogenesis of IH.

In vertebrate definitive hematopoiesis, nascent hematopoietic stem/progenitor cells (HSPCs) migrate to and reside in proliferative hematopoietic microenvironment for transitory expansion. In this process, well-established DNA damage response pathways are vital to resolve the replication stress, which is deleterious for genome stability and cell survival. However, the detailed mechanism on the response and repair of the replication stress-induced DNA damage during hematopoietic progenitor expansion remains elusive. Here we report that a novel zebrafish mutantcas003 with nonsense mutation in topbp1 gene encoding topoisomerase II β binding protein 1 (TopBP1) exhibits severe definitive hematopoiesis failure. Homozygous topbp1cas003 mutants manifest reduced number of HSPCs during definitive hematopoietic cell expansion, without affecting the formation and migration of HSPCs. Moreover, HSPCs in the caudal hematopoietic tissue (an equivalent of the fetal liver in mammals) in topbp1cas003 mutant embryos are more sensitive to hydroxyurea (HU) treatment. Mechanistically, subcellular mislocalization of TopBP1cas003 protein results in ATR/Chk1 activation failure and DNA damage accumulation in HSPCs, and eventually induces the p53-dependent apoptosis of HSPCs. Collectively, this study demonstrates a novel and vital role of TopBP1 in the maintenance of HSPCs genome integrity and survival during hematopoietic progenitor expansion.

The term neurotranscriptomics is used here to describe genome-wide analysis of neural control of transcriptomes. In this report, next-generation RNA sequencing was using to analyze the effects of neonatal (5-days-of-age) surgical stimulus deprivation on the adult rat pineal transcriptome. In intact animals, more than 3000 coding genes were found to exhibit differential expression (adjusted-p < 0.001) on a night/day basis in the pineal gland (70% of these increased at night, 376 genes changed more than 4-fold in either direction). Of these, more than two thousand genes were not previously known to be differentially expressed on a night/day basis. The night/day changes in expression were almost completely eliminated by neonatal removal (SCGX) or decentralization (DCN) of the superior cervical ganglia (SCG), which innervate the pineal gland. Other than the loss of rhythmic variation, surgical stimulus deprivation had little impact on the abundance of most genes; of particular interest, expression levels of the melatonin-synthesis-related genes Tph1, Gch1, and Asmt displayed little change (less than 35%) following DCN or SCGX. However, strong and consistent changes were observed in the expression of a small number of genes including the gene encoding Serpina1, a secreted protease inhibitor that might influence extracellular architecture. Many of the genes that exhibited night/day differential expression in intact animals also exhibited similar changes following in vitro treatment with norepinephrine, a superior cervical ganglia transmitter, or with an analog of cyclic AMP, a norepinephrine second messenger in this tissue. These findings are of significance in that they establish that the pineal-defining transcriptome is established prior to the neonatal period. Further, this work expands our knowledge of the biological process under neural control in this tissue and underlines the value of RNA sequencing in revealing how neurotransmission influences cell biology.

A novel photonic suspension array has been developed for multiplex immunoassay. The carriers of this array were silica colloidal crystal beads (SCCBs). The codes of these carriers have characteristic reflection peaks originating from their structural periodicity; therefore they do not suffer from fading, bleaching, quenching or chemical instability. In addition, the fluorescence background of SCCBs is negligible because no fluorescence materials or dyes are involved. With a sandwich method, the proposed suspension array was used for simultaneous multiplex detection of heart failure (HF) and coronary heart disease (CAD) biomarkers in one test tube. The results showed that the three biomarkers: cardiac troponin I (cTnI), C-reactive protein (CRP) and B-type natriuretic peptide (BNP) could be assayed in the ranges of 0.1-500 ng/ml, 1-500 mg/L and 0.02-50 ng/ml with detection limits of 0.01 ng/ml, 0.36 mg/L and 0.004 ng/ml at 3σ, respectively. There were no significant differences between the photonic suspension array and traditional parallel single-analyte test. This novel method demonstrated acceptable accuracy, high detection sensitivity and reproducibility and excellent storage stability. This technique provides a new strategy for low cost, automated, and simultaneous multiplex immunoassays of bio-markers.

Tyrosine-imprinted polymeric beads with diameters in the range 120–140 mm were prepared in an aqueous system by seed swelling and suspension polymerization using trimethylolpropane trimethacrylate (TRIM) as the crosslinking agent and acrylamide (AM), 2-vinylpyridine (VP) and/or 2-acrylamido-2-methylpropane sulphonic acid (AMPS), respectively, as functional monomers (FMs). The molecular recognition properties, dynamic adsorption behaviours and regeneration capabilities of the molecularly imprinted beads (MIBs) were investigated via a solid-phase extraction method. The functional monomers were found to be indispensable for preparing MIBs with highly specific molecular recognition properties. Irrespective of the choice of FM, when the FM/TRIM molar ratio was 4:15 the MIBs prepared exhibited the most desirable properties for the purposes of this study. When only one FM was used, it was found that AMPS provided the best solution as far as all the adsorption, recognition and regeneration capabilities of the MIBs were concerned. However, MIBs with the best molecular recognition and adsorption properties, and with only a slight sacrifice in their regeneration properties, were prepared using AMPS and VP as bifunctional monomers. For such MIBs, the initial separation factor, α, and static distribution coefficient, K D , were 2.01 and 2.15 ml/g, respectively.

Purpose: To address the hypothesis that the tissue processing methods of solvent dehydration and freeze-drying would differentially affect the physicochemical characteristics of four commercially available bone allografts and the adhesion and differentiation of human bone marrow-derived mesenchymal stromal cells (hBMSCs) on such substrates in vitro. Materials and Methods: The surface morphology, surface area, and elemental composition of four commercially available cancellous bone allografts were examined using SEM, Brunauer-Emmett-Teller (BET) gas adsorption, and inductively coupled plasma (ICP) analyses. SEM was also employed to compare the allograft surfaces to that of human bone exposed by in vitro osteoclastic resorption. The allografts were seeded with hBMSCs, and the number of adhered cells was assessed at 3 and 7 days. Alkaline phosphatase (ALP) activity was quantified as a measure of osteogenic differentiation after 21 days. Results: Marked differences were seen between the physicochemical characteristics of the solvent-dehydrated and freezedried allografts, as well as between their resulting bone microarchitectures and that of osteoclast-resorbed human bone. Increased hBMSC adhesion and differentiation were observed on the solvent-dehydrated allografts compared to freezedried allografts, which suggests a higher putative osteogenic potential. The latter was attributed to better preservation of the bone collagen microarchitecture integrity, which may provide not only a more complex substrate architecture, but also a more favorable microenvironment to allow nutrients and oxygen to flow to the adhered cells. Conclusion: Commercially available cancellous bone allografts significantly differ in their physicochemical characteristics, stemming from differences in tissue processing and sterilization methods undertaken by tissue banks. These differences impact the response of MSCs in vitro and may alter the biologic performance of the grafts in vivo. Therefore, it is important to consider these characteristics when choosing a bone substitute for clinical application, as the physicochemical properties of the grafts play a crucial role in their interactions with the biologic environment and subsequent incorporation into the native bone. [ABSTRACT FROM AUTHOR]

This study explores the safety and effect of acute cerebral infarction treatment by microcatheter injection of tirofiban combined with a Solitaire AB stent and/or stent implantation. Emergency cerebral angiograms showing the responsible vascular occlusion of 120 acute cerebral infarction patients who underwent emergency endovascular thrombectomy were included in the study. These patients were randomly divided into two groups using the random number table method: treatment group (n=60) that received thrombectomy (with cerebral artery stents) combined with intracerebral injection of tirofiban and control group (n=60) that only received thrombectomy (with cerebral artery stents alone). The baseline data, cerebral angiography before and after surgery, hospitalization, and follow-up results of patients in these two groups were compared. Furthermore, the incidence of major adverse cerebrovascular events of these two groups was compared (90-day modified Rankin scale, a score of 0–2 indicates a good prognosis). The difference between baseline clinical data and brain angiography between these two groups was not statistically significant. Patients in the treatment group had a higher prevalence of thrombolysis in cerebral infarction grade 2b/3 than patients in the control group (88.3% (53/60) vs 66.7% (40/60), P=0.036). Moreover, the National Institutes of Health Stroke Scale scores 7 days after surgery and the 90-day prognosis were all better for the patients who received tirofiban (P=0.048 and P=0.024). Mechanical thrombectomy with Solitaire AB stents in combination with the injection of tirofiban through a microcatheter appears to be safe and effective for the endovascular treatment of acute ischemic stroke.

Given its high morbidity, disability, and mortality rates, ischemic stroke (IS) is a severe disease posing a substantial public health threat. Although early thrombolytic therapy is effective in IS treatment, the limited time frame for its administration presents a formidable challenge. Upon occurrence, IS triggers an ischemic cascade response, inducing the brain to generate endogenous protective mechanisms against excitotoxicity and inflammation, among other pathological processes. Stroke patients often experience limited recovery stages. As a result, activating their innate self-protective capacity [endogenous brain protection (EBP)] is essential for neurological function recovery. Acupuncture has exhibited clinical efficacy in cerebral ischemic stroke (CIS) treatment by promoting the human body's self-preservation and "Zheng Qi" (a term in traditional Chinese medicine (TCM) describing positive capabilities such as self-immunity, self-recovery, and disease prevention). According to research, acupuncture can modulate astrocyte activity, decrease oxidative stress (OS), and protect neurons by inhibiting excitotoxicity, inflammation, and apoptosis via activating endogenous protective mechanisms within the brain. Furthermore, acupuncture was found to modulate microglia transformation, thereby reducing inflammation and autoimmune responses, as well as promoting blood flow restoration by regulating the vasculature or the blood--brain barrier (BBB). However, the precise mechanism underlying these processes remains unclear. Consequently, this review aims to shed light on the potential acupuncture-induced endogenous neuroprotective mechanisms by critically examining experimental evidence on the preventive and therapeutic effects exerted by acupuncture on CIS. This review offers a theoretical foundation for acupuncture-based stroke treatment. [ABSTRACT FROM AUTHOR]

Vertebrate erythropoiesis involves nuclear and chromatin condensation at the early stages of terminal differentiation, which is a unique process to distinguish mature erythrocytes from erythroblasts. However, the underlying mechanisms of chromatin condensation during erythrocyte maturation remain elusive. Here, we reported a novel zebrafish mutantcas7 with erythroid maturation deficiency. Positional cloning showed that a single base mutation in tprb gene, which encodes nucleoporin translocated promoter region (Tpr), is responsible for the disrupted erythroid maturation and upregulation of erythroid genes, including ae1-globin and be1-globin. Further investigation revealed that deficient erythropoiesis in tprbcas7 mutant was independent on HIF signaling pathway. The proportion of euchromatin was significantly increased, whereas the percentage of heterochromatin was markedly decreased in tprbcas7 mutant. In addition, TPR knockdown in human K562 cells also disrupted erythroid differentiation and dramatically elevated the expression of globin genes, which suggests that the functions of TPR in erythropoiesis are highly conserved in vertebrates. Taken together, this study revealed that Tpr played vital roles in chromatin condensation and gene regulation during erythroid maturation in vertebrates. [ABSTRACT FROM AUTHOR]

Fate determination and expansion of Hematopoietic Stem and Progenitor Cells (HSPCs) is tightly regulated on both transcriptional and post-transcriptional level. Although transcriptional regulation of HSPCs have achieved a lot of advances, its post-transcriptional regulation remains largely underexplored. The small size and high fecundity of zebrafish makes it extraordinarily suitable to explore novel genes playing key roles in definitive hematopoiesis by large-scale forward genetics screening. Here, we reported a novel zebrafish mutant line gemin5cas008 with a point mutation in gemin5 gene obtained by ENU mutagenesis and genetic screening, causing an earlier stop codon next to the fifth WD repeat. Gemin5 is an RNA-binding protein with multifunction in post-transcriptional regulation, such as regulating the biogenesis of snRNPs, alternative splicing, stress response, and translation control. The mutants displayed specific deficiency in definitive hematopoiesis without obvious defects during primitive hematopoiesis. Further analysis showed the impaired definitive hematopoiesis was due to defective proliferation of HSPCs. Overall, our results indicate that Gemin5 performs an essential role in regulating HSPCs proliferation. [ABSTRACT FROM AUTHOR]

To improve the stability of fucoxanthin, fucoxanthin liposomes (L) were prepared by the thinfilm ultrasound method, and fucoxanthin liposomes were modified with sodium alginate and chitosan by an electrostatic deposition method. The release characteristics of fucoxanthin in different types of liposomes with in vitro gastrointestinal simulation were studied. Under the optimum conditions, the results showed that the encapsulation efficiency of prepared liposomes could reach 88.56 ± 1.40% (m/m), with an average particle size of 295.27 ± 7.28 nm, a Zeta potential of -21.53 ± 2.00 mV, a polydispersity index (PDI) of 0.323 ± 0.007 and a loading capacity of 33.3 ± 0.03% (m/m). Compared with L and chitosan modified fucoxanthin liposomes (CH), sodium alginate and chitosan modified fucoxanthin liposomes (SA-CH) exhibited higher storage stability, in vitro bioaccessibility and antioxidant activity after gastrointestinal digestion. Sodium alginate and chitosan co-modified liposomes can be developed as formulations for encapsulation and delivery of functional ingredients, providing a theoretical basis for developing new fucoxanthin series products. [ABSTRACT FROM AUTHOR]