Can avian influenza A (H7N9) virus be transmitted between unrelated individuals in a hospital setting?

Rheumatoid arthritis (RA) is a chronic inflammatory disease leading to joint destruction and disability. Peroxisome proliferator-activated receptor-gamma coactivator-1 beta (PGC-1β) is a transcriptional coactivator that plays important roles in regulating multiple aspects of energy metabolism and cytokine signaling pathways. PGC-1β overexpression leads to the attenuation of macrophage-mediated inflammation. In this study, we aimed to determine the expression of PGC-1β in RA synovium and fibroblast-like synoviocytes (FLS), and explore the mechanisms of PGC-1β on both the proinflammatory effects and apoptosis in RA-FLS.

SQUAMOSA-promoter binding protein (SBP)-box genes encode a family of plant-specific transcription factors that play vital roles in plant growth and development. In this study, 15 SBP-box genes were identified and isolated from Citrus clementina (CclSBPs), where 10 of these genes were predicted to be putative targets of Citrus clementina microRNA156 (CclmiR156). The 15 CclSBP genes could be classified into six groups based on phylogenetic analysis, diverse intron⁻exon structure, and motif prediction, similar to the SQUAMOSA promoter binding protein-like (SPL) gene family of Populus trichocarpa and Arabidopsis thaliana. Furthermore, CclSBPs classified into a group/subgroup have similar gene structures and conserved motifs, implying their functional redundancy. Tissue-specific expression analysis of CclSBPs demonstrated their diversified expression patterns. To further explore the potential role of CclSBPs during floral inductive water deficits, the dynamic changes of the 15 CclSBPs were investigated during floral inductive water deficits, and the results showed that some CclSBPs were associated with floral induction. Among these genes, CclSBP6 was not homologous to the Arabidopsis SBP-box gene family, and CclSBP7 was regulated by being alternatively spliced. Therefore, CclSBP6 and CclSBP7 were genetically transformed in Arabidopsis. Overexpression of the two genes changed the flowering time of Arabidopsis.

Mild brief hypoxia can protect against neuronal damage induced by epileptic seizures, at least in part by inhibiting apoptosis. Further elucidation of the antiepileptic mechanisms and optimization of the conditioning protocols are required before this strategy can be considered for clinical intervention. In this study, we compared the effects of different hypoxic preconditioning protocols on spontaneous recurrent seizures (SRS), intracellular free calcium concentration ([Ca(2+)]i), and apoptosis rate following pilocarpine-induced status epilepticus (SE). Male Sprague Dawley rats were subjected to either chronic intermittent hypobaric hypoxia (CIHH) or chronic intermittent normobaric hypoxia (CINH) (both for 6h/day × 28 consecutive days) prior to pilocarpine-induced SE. The possible anticonvulsant and neuroprotective effects of CIHH and CINH were compared by video monitoring of behavioral seizure activity (frequency, delay), Nissl staining and Fluoro-Jade B (FJB) staining to examine changes in the morphology of hippocampal pyramidal neurons, and flow cytometry to detect the quantification of [Ca(2+)]i and cell apoptosis. Both hypoxic preconditioning protocols reduced the frequency and severity of SRS, suppressed post-ictal [Ca(2+)]i elevations, and inhibited neuronal apoptosis in the rat hippocampus compared to pilocarpine alone, but CIHH was more effective than CINH. Thus, mild hypoxic pretreatment, particularly when delivered as CIHH, may be a novel strategy for the clinical prevention and treatment of epilepsy.

To explore the correlation between matrix metalloproteinase- (MMP-) 3 and histological synovitis in rheumatoid arthritis (RA).

Pollen tube growth and endosperm development are important for fertilization and seed formation. The genetic mechanism of the processes remains poorly understood. This study reports the functional characterization of AtTFIIB1 in pollen tube growth and endosperm development. AtTFIIB1 shares 86% and 44% similarity with AtTFIIB2 and AtTFIIB3/AtpBRP2, respectively. It is expressed in many tissues including vegetative nuclei and generative cells of pollen grains and pollen tubes, endosperm, and embryos. It is thus different from AtTFIIB2, whose expression is not found in the endosperm and vegetative nucleus of mature pollen, and AtTFIIB3/AtpBRP2, which is expressed mostly in male gametophytes and weakly in seeds. Mutations in AtTFIIB1 caused a drastic retardation of pollen tube growth and endosperm development, as well as impaired pollen tube guidance and reception, leading to disruption of fertilization and seed development. Expression of AtTFIIB2 driven by the AtTFIIB1 promoter could restore the defective pollen tube growth, guidance, and reception completely, but only partially recovered the seed development in attfiib1, whilst expression of AtTFIIB3/AtpBRP2 driven by the AtTFIIB1 promoter could rescue only the defective attfiib1 seeds. All these results suggest that AtTFIIB1 plays important roles in pollen tube growth, guidance, and reception as well as endosperm development and is partially functionally different from AtTFIIB2 and AtTFIIB3/AtpBRP2.

Rheumatoid arthritis fibroblast-like synoviocytes (RA-FLSs) actively drive joint inflammation and degradation by producing inflammatory cytokines and matrix-degrading molecules, making them key factors in the pathogenesis of RA. Cylindromatosis (CYLD) is a tumor suppressor that downregulates nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation by deubiquitinating NF-κB essential modulator and tumor necrosis factor receptor-associated factors 2 and 6. In this study, we aimed to determine CYLD expression in the synovium of patients with RA, analyze its correlation with NF-κB activation and clinical disease activity, further investigate CYLD expression in RA-FLSs, and explore CYLD's roles and mechanisms in the pro-inflammatory effects, proliferation, apoptosis, and cell cycles of RA-FLSs.

Background Orexin and its receptors are critical regulating sympathetic vasomotor tone under physiological and pathophysiological conditions. Orexin receptor 1 ( OXR 1) is upregulated in the paraventricular nucleus ( PVN ) in the hypothalamus and contributes to increased sympathetic outflow in obese Zucker rats ( OZR s). We hypothesized that silencing OXR 1 expression in the PVN decreases heightened blood pressure and elevated sympathetic outflow in OZR s. Methods and Results An adeno-associated virus ( AAV ) vector containing a short hairpin RNA (sh RNA ) targeting rat OXR 1 was designed to silence OXR 1 expression in the PVN . The AAV - OXR 1-sh RNA or scrambled sh RNA was injected into the PVN in OZR s. The arterial blood pressure in free-moving OZR s was continuously monitored by using a telemetry approach. The firing activity of spinally projecting PVN neurons in rat brain slices was recorded 3 to 4 weeks after injection of viral vectors. The free-moving OZR s treated with AAV - OXR 1-sh RNA had markedly lower OXR 1 expression and lower mean arterial blood pressure, heart rate, and ratio of low- to high-frequency components of heart rate variability compared with OZR s treated with scrambled sh RNA . Furthermore, AAV - OXR 1-sh RNA treatment markedly reduced renal sympathetic nerve activity and attenuated sympathoexcitatory response induced by microinjection of orexin A into the PVN . In addition, treatment with AAV - OXR 1-sh RNA substantially decreased the basal firing activity of spinally projecting PVN neurons in OZR s and attenuated the excitatory effect of orexin A on the firing activity of these neurons. Conclusions These data suggest that chronic downregulation of OXR 1 expression in the PVN reduces sympathetic vasomotor tone in obesity-related hypertension.

Increased expression of angiotensin II AT1A receptor (encoded by Agtr1a) and Na+-K+-Cl- cotransporter-1 (NKCC1, encoded by Slc12a2) in the hypothalamic paraventricular nucleus (PVN) contributes to hypertension development. However, little is known about their transcriptional control in the PVN in hypertension. DNA methylation is a critical epigenetic mechanism that regulates gene expression. Here, we determined whether transcriptional activation of Agtr1a and Slc12a2 results from altered DNA methylation in spontaneously hypertensive rats (SHR). Methylated DNA immunoprecipitation and bisulfite sequencing-PCR showed that CpG methylation at Agtr1a and Slc12a2 promoters in the PVN was progressively diminished in SHR compared with normotensive Wistar-Kyoto rats (WKY). Chromatin immunoprecipitation-quantitative PCR revealed that enrichment of DNA methyltransferases (DNMT1 and DNMT3A) and methyl-CpG binding protein 2, a DNA methylation reader protein, at Agtr1a and Slc12a2 promoters in the PVN was profoundly reduced in SHR compared with WKY. By contrast, the abundance of ten-eleven translocation enzymes (TET1-3) at Agtr1a and Slc12a2 promoters in the PVN was much greater in SHR than in WKY. Furthermore, microinjecting of RG108, a selective DNMT inhibitor, into the PVN of WKY increased arterial blood pressure and correspondingly potentiated Agtr1a and Slc12a2 mRNA levels in the PVN. Conversely, microinjection of C35, a specific TET inhibitor, into the PVN of SHR markedly reduced arterial blood pressure, accompanied by a decrease in Agtr1a and Slc12a2 mRNA levels in the PVN. Collectively, our findings suggest that DNA hypomethylation resulting from the DNMT/TET switch at gene promoters in the PVN promotes transcription of Agtr1a and Slc12a2 and hypertension development.

Trees have developed a broad spectrum of molecular mechanisms to counteract oxidative stress. Secondary metabolites via phenolic compounds emblematized the hidden bridge among plant kingdom, human health, and oxidative stress. Although studies have demonstrated that abiotic stresses can increase the production of medicinal compounds in plants, research comparing the efficiency of these stresses still needs to be explored. Thus, the present research paper provided an exhaustive comparative metabolomic study in Dalbergia odorifera under salinity (ST) and waterlogging (WL).

Pollen tube reception involves a pollen tube-synergid interaction that controls the discharge of sperm cells into the embryo sac during plant fertilization. Despite its importance in the sexual reproduction of plants, little is known about the role of gene regulation in this process. We report here that the pollen-expressed transcription factors MYB97, MYB101 and MYB120 probably control genes whose encoded proteins play important roles in Arabidopsis thaliana pollen tube reception. They share a high amino acid sequence identity and are expressed mainly in mature pollen grains and pollen tubes. None of the single or double mutants of these three genes exhibited any visible defective phenotype. Although the myb97 myb101 myb120 triple mutant was not defective in pollen development, pollen germination, pollen tube growth or tube guidance, the pollen tubes of the triple mutants exhibited uncontrolled growth and failed to discharge their sperm cells after entering the embryo sac. In addition, the myb97 myb101 myb120 triple mutation significantly affected the expression of a group of pollen-expressed genes in mature pollen grains. All these results indicate that MYB97, MYB101 and MYB120 participate in pollen tube reception, possibly by controlling the expression of downstream genes.

Objective. Human umbilical cord mesenchymal stem cells (hUC-MSCs) potentially differentiate to various types of cells including neuron-like cells. The natural polyphenol resveratrol benefits patients with many diseases including ischemic brain injury. We hypothesize that resveratrol induces differentiation of hUC-MSCs into neuron-like cells. Methods. Flow cytometry was used to determine the surface antigens in different stage of hUC-MSCs (P2, P5, and P10). Nestin, neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP) were detected by immunocytochemistry, Western blotting, and real time RT-PCT. The cultured hUC-MSCs were treated with resveratrol at different concentrations (0, 7.5, 15.0, and 30.0 mg/L). Nestin, GFAP, and NSE protein and mRNA were measured at posttreatment time points of 2 h, 4 h, 6 h, 12 h, and 24 h. Results. Neuron-like cells were found in hUC-MSCs treated by resveratrol at concentrations of 15.0 and 30.0 mg/L, but not in hUC-MSCs treated with vehicle and 7.5 mg/L resveratrol. Furthermore, immunocytochemical staining revealed that nestin and NSE immunoreactivities were positive in resveratrol-treated hUC-MSCs at concentrations of 15.0 and 30.0 mg/L. Resveratrol treatment significantly increased nestin and NSE protein and mRNA levels 4 h after the treatment. However, resveratrol treatment did not change GFAP immunoreactivities and protein and mRNA expression levels in cultured hUC-MSCs. Conclusions. Taken together, resveratrol treatment induces a differentiation of hUC-MSCs into neuron-like cells at relatively high concentrations.

Glutamate AMPA receptors (AMPARs) lacking GluA2 subunit are calcium permeable (CP-AMPARs), which are increased in the hypothalamic paraventricular nucleus (PVN) and maintain sympathetic outflow in hypertension. Here, we determined the role of α2δ-1, an NMDA receptor-interacting protein, in regulating synaptic CP-AMPARs in the hypothalamus in spontaneously hypertensive rats (SHR). Co-immunoprecipitation showed that levels of GluA1/GluA2, but not GluA2/GluA3, protein complexes in hypothalamic synaptosomes were reduced in SHR compared with Wistar-Kyoto rats (WKY). The level of GluA1/GluA2 heteromers in endoplasmic reticulum-enriched fractions of the hypothalamus was significantly lower in SHR than in WKY, which was restored by inhibiting α2δ-1 with gabapentin. Gabapentin also switched AMPAR-mediated excitatory postsynaptic currents (AMPAR-EPSCs) from inward rectifying to linear and attenuated the inhibitory effect of IEM-1460, a selective CP-AMPAR blocker, on AMPAR-EPSCs in spinally projecting PVN neurons in SHR. Furthermore, co-immunoprecipitation revealed that α2δ-1 directly interacted with GluA1 and GluA2 in the hypothalamus of rats and humans. Levels of α2δ-1/GluA1 and α2δ-1/GluA2 protein complexes in the hypothalamus were significantly greater in SHR than in WKY. Disrupting the α2δ-1-AMPAR interaction with an α2δ-1 C terminus peptide normalized GluA1/GluA2 heteromers in the endoplasmic reticulum of the hypothalamus diminished in SHR. In addition, α2δ-1 C terminus peptide diminished inward rectification of AMPAR-EPSCs and the inhibitory effect of IEM-1460 on AMPAR-EPSCs of PVN neurons in SHR. Thus, α2δ-1 augments synaptic CP-AMPARs by inhibiting GluA1/GluA2 heteromeric assembly in the hypothalamus in hypertension. These findings extend our understanding of the molecular basis of sustained sympathetic outflow in neurogenic hypertension.

Orchestrating the transition from reversible medial hypertrophy to irreversible plexiform lesions is crucial for pulmonary arterial hypertension related to congenital heart disease (CHD-PAH). Transgelin is an actin-binding protein that modulates pulmonary arterial smooth muscle cell (PASMC) dysfunction. In this study, we aimed to probe the molecular mechanism and biological function of transgelin in the pathogenesis of CHD-PAH.

Reportedly, nestin was re-expressed in proliferative synthetic-type pulmonary artery smooth muscle cells (PASMCs) and obligatory for PASMC proliferation in pulmonary arterial hypertension (PAH). Accordingly, nestin is increased in pulmonary vascular lesions of congenital heart disease (CHD)-associated PAH patients. We tested the hypothesis whether nestin was re-expressed in proliferative synthetic-type PASMCs and associated with pulmonary vascular remodeling in CHD-PAH.

Volume-regulated anion channels (VRACs) are critically involved in regulating cell volume, and leucine-rich repeat-containing protein 8A (LRRC8A, SWELL1) is an obligatory subunit of VRACs. Cell swelling occurs early after brain ischemia, but it is unclear whether neuronal LRRC8a contributes to ischemia-induced glutamate release and brain injury. We found that Lrrc8a conditional knockout (Lrrc8a-cKO) mice produced by crossing NestinCre+/- with Lrrc8aflox+/+ mice died 7-8 weeks of age, indicating an essential role of neuronal LRRC8A for survival. Middle cerebral artery occlusion (MCAO) caused an early increase in LRRC8A protein levels in the hippocampus in wild-type (WT) mice. Whole-cell patch-clamp recording in brain slices revealed that oxygen-glucose deprivation significantly increased the amplitude of VRAC currents in hippocampal CA1 neurons in WT but not in Lrrc8a-cKO mice. Hypotonicity increased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) in hippocampal CA1 neurons in WT mice, and this was abolished by DCPIB, a VRAC blocker. But in Lrrc8a-cKO mice, hypotonic solution had no effect on the frequency of sEPSCs in these neurons. Furthermore, the brain infarct volume and neurological severity score induced by MCAO were significantly lower in Lrrc8a-cKO mice than in WT mice. In addition, MCAO-induced increases in cleaved caspase-3 and calpain activity, two biochemical markers of neuronal apoptosis and death, in brain tissues were significantly attenuated in Lrrc8a-cKO mice compared with WT mice. These new findings indicate that cerebral ischemia increases neuronal LRRC8A-dependent VRAC activity and that VRACs contribute to increased glutamatergic input to hippocampal neurons and brain injury caused by ischemic stroke.

Chronic stress impairs GABAA (GABA type A) receptor-mediated inhibition in the hypothalamic paraventricular nucleus (PVN). It is not clear whether GABAB receptor function is also altered. We hypothesize that chronic stress alters GABAB receptor function in PVN corticotrophin-releasing hormone (CRH) neurons to control hypothalamus-pituitary-adrenal axis activity.

Both the sympathetic nervous system and the renin-angiotensin system are critically involved in hypertension development. Although angiotensin II (Ang II) stimulates hypothalamic paraventricular nucleus (PVN) neurons to increase sympathetic vasomotor tone, the molecular mechanism mediating this action remains unclear. The glutamate NMDAR in the PVN controls sympathetic outflow in hypertension. In this study, we determined the interaction between α2δ-1 (encoded by Cacna2d1), commonly known as a Ca2+ channel subunit, and NMDARs in the hypothalamus and its role in Ang II-induced synaptic NMDAR activity in PVN presympathetic neurons. Coimmunoprecipitation assays showed that α2δ-1 interacted with the NMDAR in the hypothalamus of male rats and humans (both sexes). Ang II increased the prevalence of synaptic α2δ-1-NMDAR complexes in the hypothalamus. Also, Ang II increased presynaptic and postsynaptic NMDAR activity via AT1 receptors, and such effects were abolished either by treatment with pregabalin, an inhibitory α2δ-1 ligand, or by interrupting the α2δ-1-NMDAR interaction with an α2δ-1 C terminus-interfering peptide. In Cacna2d1 knock-out mice (both sexes), Ang II failed to affect the presynaptic and postsynaptic NMDAR activity of PVN neurons. In addition, the α2δ-1 C terminus-interfering peptide blocked the sympathoexcitatory response to microinjection of Ang II into the PVN. Our findings indicate that Ang II augments sympathetic vasomotor tone and excitatory glutamatergic input to PVN presympathetic neurons by stimulating α2δ-1-bound NMDARs at synapses. This information extends our understanding of the molecular basis for the interaction between the sympathetic nervous and renin-angiotensin systems and suggests new strategies for treating neurogenic hypertension.SIGNIFICANCE STATEMENT Although both the sympathetic nervous system and renin-angiotensin system are closely involved in hypertension development, the molecular mechanisms mediating this involvement remain unclear. We showed that α2δ-1, previously known as a calcium channel subunit, interacts with NMDARs in the hypothalamus of rodents and humans. Angiotensin II (Ang II) increases the synaptic expression level of α2δ-1-NMDAR complexes. Furthermore, inhibiting α2δ-1, interrupting the α2δ-1-NMDAR interaction, or deleting α2δ-1 abolishes the potentiating effects of Ang II on presynaptic and postsynaptic NMDAR activity in the hypothalamus. In addition, the sympathoexcitatory response to Ang II depends on α2δ-1-bound NMDARs. Thus, α2δ-1-NMDAR complexes in the hypothalamus serve as an important molecular substrate for the interaction between the sympathetic nervous system and the renin-angiotensin system. This evidence suggests that α2δ-1 may be a useful target for the treatment neurogenic hypertension.

Water deficit is a key factor to induce flowering in many woody plants, but reports on the molecular mechanisms of floral induction and flowering by water deficit are scarce. Here, we analyzed the morphology, cytology, and different hormone levels of lemon buds during floral inductive water deficits. Higher levels of ABA were observed, and the initiation of floral bud differentiation was examined by paraffin sections analysis. A total of 1638 differentially expressed genes (DEGs) were identified by RNA sequencing. DEGs were related to flowering, hormone biosynthesis, or metabolism. The expression of some DEGs was associated with floral induction by real-time PCR analysis. However, some DEGs may not have anything to do with flowering induction/flower development; they may be involved in general stress/drought response. Four genes from the phosphatidylethanolamine-binding protein family were further investigated. Ectopic expression of these genes in Arabidopsis changed the flowering time of transgenic plants. Furthermore, the 5' flanking region of these genes was also isolated and sequence analysis revealed the presence of several putative cis-regulatory elements, including basic elements and hormone regulation elements. The spatial and temporal expression patterns of these promoters were investigated under water deficit treatment. Based on these findings, we propose a model for citrus flowering under water deficit conditions, which will enable us to further understand the molecular mechanism of water deficit-regulated flowering in citrus.

The novel coronavirus pneumonia (COVID-19) pandemic is a great threat to human society and now is still spreading. Although several vaccines have been authorized for emergency use, only one recombinant subunit vaccine has been permitted for widespread use. More subunit vaccines for COVID-19 should be developed in the future. The receptor binding domain (RBD), located at the S protein of SARS-CoV-2, contains most of the neutralizing epitopes. However, the immunogenicity of RBD monomers is not strong enough. In this study, we fused the RBD-monomer with a modified Fc fragment of human IgG1 to form an RBD-Fc fusion protein. The recombinant vaccine candidate based on the RBD-Fc protein could induce high levels of IgG and neutralizing antibody in mice, and these could last for at least three months. The secretion of IFN-γ, IL-2 and IL-10 in the RBD-stimulated splenocytes of immunized mice also increased significantly. Our results first showed that the RBD-Fc vaccine could induce both humoral and cellular immune responses and might be an optional strategy to control COVID-19.