Long-range inhibitory neurons mediate cortical neurovascular coupling.

To meet the high energy demands of brain function, cerebral blood flow (CBF) parallels changes in neuronal activity by a mechanism known as neurovascular coupling (NVC). However, which neurons play a role in mediating NVC is not well understood. Here, we identify in mice and humans a specific population of cortical GABAergic neurons that co-express neuronal nitric oxide synthase and tachykinin receptor 1 (Tacr1). Through whole-tissue clearing, we demonstrate that Tacr1 neurons extend local and long-range projections across functionally connected cortical areas. We show that whisker stimulation elicited Tacr1 neuron activity in the barrel cortex through feedforward excitatory pathways. Additionally, through optogenetic experiments, we demonstrate that Tacr1 neurons are instrumental in mediating CBF through the relaxation of mural cells in a similar fashion to whisker stimulation. Finally, by electron microscopy, we observe that Tacr1 processes contact astrocytic endfeet. These findings suggest that Tacr1 neurons integrate cortical activity to mediate NVC.

Depletion of Circular RNA circ_CORO1C Suppresses Gastric Cancer Development by Modulating miR-138-5p/KLF12 Axis.

BACKGROUND: Gastric cancer (GC) is a common and deadly malignancy in the world. CircRNAs have emerged as important regulators in human diseases, including GC. In this work, we intended to explore the role of circ_CORO1C in GC progression and potential mechanism. METHODS: Quantitative real-time PCR (qRT-PCR) or Western blot assay was performed to examine the expression of circRNA coronin-like actin-binding protein 1C (circ_CORO1C), microRNA (miR)-138-5p and Krueppel-like factor 12 (KLF12) in clinical samples and cells. Cell colony formation ability and viability were measured by colony formation assay and methyl thiazolyl tetrazolium (MTT) assay, respectively. Expression of cell proliferation and epithelia-mesenchymal transition (EMT) biomarker was detected by Western blot analysis. And cell metastasis, including migration and invasion, and apoptosis were analyzed via Transwell assay and flow cytometry, respectively. Target relationship among circ_CORO1C, miR-138-5p and KLF12 was validated by dual-luciferase reporter assay. The in vivo role of circ_CORO1C was investigated by tumor xenograft assay. RESULTS: Circ_CORO1C and KLF12 were upregulated, while miR-138-5p was downregulated in GC tissues and cells. Circ_CORO1C knockdown suppressed colony formation ability, viability, migration, invasion and EMT in GC cells, while promoted cell apoptosis in vitro. Circ_CORO1C targeted miR-138-5p, the inhibition of which could attenuate silenced circ_CORO1C-induced inhibitory effects on GC progression. MiR-138-5p repressed the aggressive malignant behaviors of GC cells by directly targeting KLF12. Circ_CORO1C deficiency inhibited GC tumor growth in vivo. CONCLUSION: Depletion of circ_CORO1C suppressed GC progression by regulating miR-138-5p/KLF12 axis, offering a potential molecular target for GC therapy.

Does Mucosal B1 Activation Result in the Accumulation of Peak IgM During Chronic Intrarectal SIVmac239 Exposure to Protect Chinese-Origin Rhesus Macaques From Disease Progression?

Human immunodeficiency virus (HIV) infection is characterized by a dynamic process and highly variable progression. Although extensive comparisons have been reported between the minority of non-progressors (NPGs) and the majority of progressors (PGs), the underlying mechanism is still unclear. One reason for this is that the initial onset of infection is very difficult to track, particularly when men who have sex with men (MSM) are predominantly responsible for the transmission of human HIV. To find potential early protection strategies against later progression during chronic mucosal exposure, 10 Chinese-origin rhesus macaques (ChRhs) that underwent repetitive simian immunodeficiency virus (SIV) intrarectal exposure were longitudinally tracked. The results of the periodic detection of peripheral blood mononuclear cells (PBMCs) and colorectal mucosal lamina propria mononuclear cells (LPMCs) with immunoglobulins in rectal fluid were compared between non-progressive and progressive subgroups, which were classified based on their circulating viral loads. As a result, four NPGs and six PGs were observed after disease onset for 2 months. Upon comparing the mucosal and systemic immune responses, the PBMC response did not differ between the two subgroups. Regarding LPMCs, the increased activation of B1a/B1 cells among B cells and a peak in IgM in rectal fluid was observed approximately 10 days after the first exposure, followed by consistently low viremia in the four non-progressive ChRhs. In the six progressive ChRhs, neither B cell activation nor a peak in IgM was observed, while a robust elevation in IgG was observed, followed by consistently high viremia post exposure. Based on the PBMC-LPMC disparity between the subgroups of monkeys, we hypothesize that early B1 activation in LPMCs that result in an IgM peak might attenuate the entry and acquisition of SIV in the mucosa, resulting in very low dissemination into blood. Our models have suggested that the use of early surveillance both systemically and in the mucosa to comprehensively determine virus-host interactions would be informative for mucosal vaccine development.

Repressive effect of primary virus replication on superinfection correlated with gut-derived central memory CD4(+) T cells in SHIV-infected Chinese rhesus macaques.

A possible mechanism of susceptibility to superinfection with simian-human immunodeficiency virus (SHIV)-1157ipd3N4 was explored in twelve SHIVSF162P3-infected Chinese rhesus macaques. Based on the kinetics of viral replication for the second infecting virus following SHIV-1157ipd3N4 inoculation, the monkeys were divided into two groups: those relatively resistant to superinfection (SIR) and those relatively sensitive to superinfection (SIS). We found that superinfection-resistant macaques had high primary viremia, whereas superinfection-sensitive macaques had low primary viremia, suggesting that primary SHIVSF162P3 infection with a high viral-replication level would repress superinfection with a heterologous SHIV-1157ipd3N4. Although no correlation of protection against superinfection with virus-specific CD4(+) T cell or CD8(+) T cell immune responses from gut was observed prior to superinfection, superinfection susceptibility was strongly correlated with CD4(+) Tcm cells from gut both prior to the second infecting virus inoculation and on day 7 after superinfection, but not with CD4(+) Tem cells from gut or with CD4(+) Tcm cells from peripheral blood and lymph node. These results point to the important roles of gut-derived CD4(+) Tcm cells for the study of the mechanisms of protection against superinfection and the evaluation of the safety and efficacy of vaccines and therapies against acquired immune deficiency syndrome (AIDS).

Interleukin-21 up-regulates interleukin-21R expression and interferon gamma production by CD8+ cells in SHIV-infected macaques.

Interleukin-21 (IL-21) is produced primarily by CD4+ T cells and regulates immunity against human/simian immunodeficiency virus (HIV/SIV) infection. Activated CD8+ cells and their secreted interferon-gamma (IFN-γ) are crucial for the control of acute HIV/SIV infection. However, whether IL-21 can regulate IFN-γ production by CD8+ cells remains controversial. Rhesus macaques (RMs, n = 8) were infected with SHIV and the levels of plasma IL-21, IFN-γ and the frequency of peripheral blood activated T cells were measured longitudinally. Following infection with SHIV, the levels of plasma IL-21 and IFN-γ increased, peaked at 17 days postinfection and declined later. Furthermore, IL-21 induced IL-21 receptor (IL-21R) and IFN-γ, perforin, but not granmyze B, expression in CD8+ cells from four selected SHIV-infected RMs. The regulatory effect of IL-21 on CD8+ cell function appeared to be associated with increased levels of STAT3, but not STAT5, phosphorylation in CD8+ cells from SHIV-infected RMs. In parallel, treatment with soluble IL-21R/Fc, an inhibitor of IL-21-induced activation of JAK1/3 and STAT3, abrogated IL-21-induced STAT3 activation and IFN-γ production in CD8+ cells from SHIV-infected RMs in vitro. Our data indicated that IL-21 was a positive regulator of IFN-γ-secreting CD8+ cells and increased the STAT3 phosphorylation, regulating T-cell immunity against acute SHIV infection in RMs. Our findings may provide a new basis for the development of immunotherapies for the control of SHIV/HIV infection.

Circulating IL-21 levels increase during early simian-human immunodeficiency virus infection in macaques.

The cytokine interleukin-21 (IL-21) regulates viral pathogenesis in individuals infected with human and simian immunodeficiency viruses. However, because the time of initial infection with HIV in humans is rarely known, the dynamics of IL-21 production during the first weeks have not been adequately explored. In the present study, we used rhesus macaques to model the first stages of infection. Twenty-two rhesus macaques were infected rectally with simian-human immunodeficiency virus (SHIV)-1157ipd3N4, and for 12 weeks, replication of the virus, the numbers of CD4+ and CD8+ T cells, and the levels of plasma IL-21 were monitored. Our study demonstrated that plasma levels of IL-21 increased during the early phase of SHIV infection when compared with the values observed before inoculation. We conclude that IL-21 has a likely role in the immunopathogenesis of HIV/SIV/SHIV.

[Circadian rhythm of melatonin and blood pressure changes in patients with essential hypertension].

OBJECTIVE: To observe the association between melatonin (MLT) secretion and blood pressure changes during 24 hours in hypertensive patients (HPT) with (dipping) or without (non-dipping) night time blood pressure reduction. METHODS: The 24-hour blood pressure and urine 6-SMT (6-sulfatoxymelatonin, metabolism product of MLT in urine) in the daytime and nighttime were measured in normal control subjects (n = 20), non-dipping HPT group (n = 32) and dipping HPT group (n = 36). RESULTS: As expected, blood pressure reduction during the night was significantly lower in non-dipping HPT group compared to control and dipping HPT groups. Nighttime 6-SMT was significantly higher than daytime 6-SMT in all groups and nighttime urine 6-SMT levels and ratio of nighttime/daytime urine 6-SMT levels were significantly lower in non-dipping HPT group compared to control and dipping HPT groups (all P < 0.01). Moreover, ratio of nighttime/daytime urine 6-SMT levels are positively correlated blood pressure reduction during nighttime (P < 0.05) in all groups. CONCLUSIONS: Circadian rhythm of MLT secretion is maintained but nighttime MLT secretion was significantly reduced and related to disorders of circadian rhythm of blood pressure in non-dipping HPT group.

Aggregation of a hydrophobically modified poly(propylene imine) dendrimer.

The poly(propylene imine) dendrimer DAB-dendr- (NH2)8 was hydrophobically modified with dodecanoyl end groups. The modified dendrimer was deposited onto mica by adsorption from solution and observed by atomic force microscopy. With the decrease of adsorption time, the modified dendrimer varied from continuous film to scattered islands. For the adsorption time of 20s the dendrimer formed a sub-monolayer thin film that contained many fractal aggregates of fractal dimension 1.80 that were > 1 microm in diameter and no more than 0.8nm thick. After 5 months at 1#1 , the initial fractal aggregates transformed into disks and other less-branched shapes with average heights of the domains of 0.6nm and 0.4nm, respectively. Formation of the fractal aggregates is explained by diffusion-limited aggregation. The slow reorganization of dendrimer molecules in the fractal aggregates occurs at a temperature well above the Tg of the dendrimer.

Evaluation of the biocompatibility of acellular porcine dermis.

The biocompatibility of an acellular porcine dermis was evaluated by in vitro methods. Endothelia cells (ECV-304) and fibroblasts (NIH-3T3) were seeded on the dermis and cultured for 1 week to assess the cell viability in the skin grafts. Results by morphological assessment and methylthiazolyl tetrazolium assay (MTT assay) indicated good biocompatibility of acellular porcine dermis, which allowed adhesion and proliferation of examined cell types. Flow chamber technique was used to evaluate the adhesive force between cells and biomaterials. There was no significant difference in cells retention ratio between control cells and experimental cells after sheared 24h. The determination of integrin alpha5 expression proved that the acellular porcine dermis did not influence the expression of integrin alpha5 in cells. The results suggested that the dermal equivalent made from pigskin is a promising material for burn treatment.

[Compatibility of a novel ethylenediamine modified polylactic acid with osteoblasts].

Biocompatibility of a newly developed ethylenediamine modified poly (DL-latic acid) (EMPLA) with osteoblasts was investigated by means of cell morphology and cell proliferation. Films of PLA and EMPLA were made by solvent casting. Osteoblasts obtained from crania of neonatal Wistar rats were cultured on surfaces of PLA and EMPLA, with glass as control. The cell morphology was observed by phase contrast microscope and the cell proliferation was determined by MTT assay. The morphology observations revealed that the osteoblasts cultured on EMPLA spread wider than those on PLA, and much more cells were confluent on EMPLA, compared to those on PLA and glass. The growth curves showed the osteoblasts on EMPLA grew faster than did those on PLA and glass. The results exhibited that the biocompatibility of EMPLA with osteoblasts is better than that of PLA and glass, which suggested wide applications of EMPLA in biomedical area, especially in tissue engineering.