Mad2 Research Articles

2730–2670 Ma rifting triggers sagduction prior to the onset of orogenesis at ca 2650 Ma: implications for gold mineralisation, Eastern Goldfields, Western Australia

The dominant structural fabric in the Eastern Goldfields is the steep north- to north-northwest-trending S2 foliation that is axial planar to upright F2 folds, developed during intense horizontal east–west shortening (D2–4 event). These structures consistently overprint D1 structures, which comprise layer-parallel S1 foliation, extensional shears, thrusts and recumbent F1 folds. The D1 event represents a separate and distinct episode of deformation with a markedly different stress regime (dominant vertical σ1), compared with the stress regime during the D2–4 events (horizontal east–west oriented σ1). There is little evidence for pre-2670 Ma ductile deformation in the Eastern Goldfields, as: (1) the ca 2730–2670 Ma greenstone sequences are deposited conformably on the older ca 2800 Ma greenstone sequences, with the first significant angular unconformities observed at the base of the post greenstone late basins; (2) a lack of schist or gneiss clasts in the late basins suggests that the surrounding uplifted sequence was largely undeformed; (3) the layer-parallel S1 foliation is observed throughout the 2720–2670 Ma greenstone sequence; and (4) the dominant low north- and south-plunges of F2 folds suggest that the sequence was predominantly flat-lying prior to strong east–west shortening (D2–4 events). The ca 2670–2655 Ma D1 event represents a period of sagduction that occurred immediately after cessation of rifting as a result of gravitational instability from deposition of dense, cold, greenstone sequences onto thinned, light, hot felsic crust. Late basins represent depocentres on the sinking greenstones during sagduction. Marked contrasts in the structural style of gold deposits, metallogeny and fluid sources, typically attributed to progressive deformation during orogenesis, could instead reflect temporally distinct mineralising events during changing tectonic regimes. In the East Yilgarn, an early plumbing system dominated by north-northwest-trending basin-controlling structures was likely established during rifting and focused fluids during multiple hydrothermal circulation events.

Regulation of IkappaB Protein Expression by Early Gestation in the Thymus of Ewes.

The thymus is an essential component of maternal immune systems that play key roles in recognizing the placenta as immunologically foreign. The inhibitor of the NF-κB (IκB) family has essential effects on the NF-κB pathway; however, it is unclear whether early pregnancy modulates the expression of the IκB family in the thymus. In this study, maternal thymuses were sampled on day 16 of nonpregnancy and different gestation stages in the ovine, and the expression of IκB proteins was analyzed. The data showed that B cell leukemia-3 and IκBβ increased; however, IκBα, IκBε, and IKKγ deceased during gestation. Furthermore, there was an increase in IκBNS and IκBζ expression values on day 13 of pregnancy; however, this decreased on day 25 of gestation. In summary, the expression of the IκB family was modulated in the thymus during early gestation, suggesting that the maternal thymus can be associated with maternal immunologic tolerance and pregnancy establishment in ewes.

The central inflammatory regulator IκBζ: induction, regulation and physiological functions.

IκBζ (encoded by NFKBIZ) is the most recently identified IkappaB family protein. As an atypical member of the IkappaB protein family, NFKBIZ has been the focus of recent studies because of its role in inflammation. Specifically, it is a key gene in the regulation of a variety of inflammatory factors in the NF-KB pathway, thereby affecting the progression of related diseases. In recent years, investigations into NFKBIZ have led to greater understanding of this gene. In this review, we summarize the induction of NFKBIZ and then elucidate its transcription, translation, molecular mechanism and physiological function. Finally, the roles played by NFKBIZ in psoriasis, cancer, kidney injury, autoimmune diseases and other diseases are described. NFKBIZ functions are universal and bidirectional, and therefore, this gene may exert a great influence on the regulation of inflammation and inflammation-related diseases.

Astaxanthin attenuated hyperuricemia and kidney inflammation by inhibiting uric acid synthesis and the NF-κ B/NLRP3 signaling pathways in potassium oxonate and hypoxanthine-induced hyperuricemia mice.

Inflammation is an important pathological feature of hyperuricemia, which in turn aggravates hyperuricemia. Astaxanthin is a carotenoid with strong antioxidant capacity and possesses many biological activities. This study was aimed to evaluate the effect of astaxanthin (ASX) on hyperuricemia and kidney inflammation in potassium oxonate (PO) and hypoxanthine (HX)-induced hyperuricemic mice. Male ICR mice were administered intragastrically with PO and HX (250 mg/kg, respectively) for 14 days. ASX was given by gavage one hour after PO and HX administration. ASX treatment significantly reversed PO and HX-induced hyperuricemia and kidney inflammation in mice as evidenced by decreased serum levels of uric acid (UA), creatinine (Cr), blood urea nitrogen (BUN), and inflammatory factors (IL-1β, IL-6, and TNF-α) and increased activities of antioxidant enzymes (CAT, SOD and GSH-Px). Furthermore, ASX administration effectively inhibited the activities of key enzymes related to UA synthesis (xanthine oxidase (XOD) and adenosine deaminase (ADA)) and modulated the protein expressions of NF-κ B p65, p-NF-κ B p65, Iκ Bα, p-Iκ Bα, NLRP3, ASC, Caspase-1, and cleavedCaspase-1 involved in inflammation pathways. Our results suggested that ASX improved hyperuricemia and kidney inflammation induced by PO and HX, probably by reducing UA synthesis and suppressing the NF-κ B and NLRP3 pathways simultaneously.

Prasugrel anti-ischemic effect in rats: Modulation of hippocampal SUMO2/3-IкBα/Ubc9 and SIRT-1/miR-22 trajectories

The beneficial role of prasugrel, a P2Y12 receptor blocker, in several neurointerventional procedures has been reviewed clinically. Beyond its antiplatelet capacity, the potential neuroprotective mechanisms of prasugrel are poorly addressed experimentally. Relevant to the imbalance between neuro-inflammation and neuroprotective pathways in cerebral ischemia/reperfusion (I/R), our study evaluated the anti-ischemic potential of prasugrel treatment through tackling novel targets. Male Wistar rats were allocated into 2 sets; set 1 (I/R 60 min/3 days) to assess the neurological deficits/biochemical impact of prasugrel and set 2 (I/R 60 min/5 days) for evaluating short memory/morphological/immunoreactive changes. Each set comprised 4 groups designated as sham, sham + prasugrel, I/R, and I/R + prasugrel. Post-administration of prasugrel for 3 and 5 days reduced neurological deficit scores and improved the spontaneous activity/short term spatial memory using the Y-maze paradigm. On the molecular level, prasugrel turned off SUMO2/3-inhibitory kappa (Iκ)Bα, Ubc9 and nuclear factor kappa (NF-κ)B. Besides, it inhibited malondialdehyde (MDA) and inactivated astrocytes by downregulating the glial fibrillary acidic protein (GFAP) hippocampal immune-expression. Conversely, it activated its target molecule cAMP, protein kinase (PK)A, and cAMP response element-binding protein (CREB) to enhance the brain-derived nuclear factor (BDNF) hippocampal content. Additionally, cAMP/PKA axis increased the hippocampal content of deacetylator silent information regulator 1 (SIRT1) and the micro RNA (miR)-22 gene expression. The crosstalk between these paths partakes in preserving hippocampal cellularity. Accordingly, prasugrel, regardless inhibiting platelets activity, modulated other cellular components; viz., SUMO2/3-IκBα/Ubc9/NF-κB, cAMP/PKA related trajectories, CREB/BDNF and SIRT1/miR-22 signaling, besides inhibiting GFAP and MDA to signify its anti-ischemic potential.

Therapeutic effect of and mechanisms underlying the effect of miR-195-5p on subarachnoid hemorrhage-induced vasospasm and brain injury in rats.

ObjectivesThere is much evidence suggesting that inflammation contributes majorly to subarachnoid hemorrhage (SAH)-induced cerebral vasospasm and brain injury. miRNAs have been found to modulate inflammation in several neurological disorders. This study investigated the effect of miR-195-5p on SAH-induced vasospasm and early brain injury in experimental rats.MethodsNinety-six Sprague-Dawley male rats were randomly and evenly divided into a control group (no SAH, sham surgery), a SAH only group, a SAH + NC-mimic group, and a SAH + miR-195-5p group. SAH was induced using a single injection of blood into the cisterna magna. Suspensions containing NC-mimic and miR-195-5p were intravenously injected into rat tail 30 mins after SAH was induced. We determined degree of vasospasm by averaging areas of cross-sections the basilar artery 24h after SAH. We measured basilar artery endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κ B), phosphorylated NF-κ B (p-NF-κ B), inhibitor of NF-κ B (Iκ Bα) and phosphorylated-Iκ Bα (p-Iκ Bα). Cell death assay was used to quantify the DNA fragmentation, an indicator of apoptotic cell death, in the cortex, hippocampus, and dentate gyrus. Tumor necrosis factor alpha (TNF-α) levels were measured using sample protein obtained from the cerebral cortex, hippocampus and dentate gyrus.ResultsPrior to fixation by perfusion, there were no significant physiological differences among the control and treatment groups. SAH successfully induced vasospasm and early brain injury. MiR-195-5p attenuated vasospasam-induced changes in morphology, reversed SAH-induced elevation of iNOS, p-NF-κ B, NF-κ B, and p-Iκ Bα and reversed SAH-induced suppression of eNOS in the basilar artery. Cell death assay revealed that MiR-195-5p significantly decreased SAH-induced DNA fragmentation (apoptosis) and restored TNF-α level in the dentate gyrus.ConclusionIn conclusion, MiRNA-195-5p attenuated SAH-induced vasospasm by up-regulating eNOS, down-regulating iNOS and inhibiting the NF-κ B signaling pathway. It also protected neurons by decreasing SAH-induced apoptosis-related cytokine TNF-α expression in the dentate gyrus. Further study is needed to elucidate the detail mechanism underlying miR-195-5p effect on SAH-induced vasospasm and cerebral injury. We believe that MiR-195-5p can potentially be used to manage SAH-induced cerebral vasospasm and brain injury.

Deformation, Magmatism, and Sulfide Mineralization in the Archean Golden Mile Fault Zone, Kalgoorlie Gold Camp, Western Australia

AbstractThe Golden Mile fault zone is a key controlling structure to the estimated 75 Moz gold endowment of the Kalgoorlie gold camp in the Yilgarn craton of Western Australia. The earliest structures in the fault are F1 folds that developed during D1 recumbent-fold and thrust deformation (<2685 ± 4 Ma). These F1 folds are overprinted by a pervasive NW- to NNW-striking S2 cleavage related to sinistral shearing beginning with 2680 ± 3 Ma D2a sinistral strike-slip and culminating with ca. 2660 Ma D2c sinistral-reverse movement. The majority of deformation in the fault zone correlates to ca. 2675 Ma D2b deformation, which is characterized by sinistral-normal kinematic indicators. Late, ca. 2650–2640 Ma D3 dextral-reverse kinematic indicators overprint the earlier D2 structures. Pyrrhotite-chalcopyrite-pyrite-sphalerite-galena assemblages were emplaced throughout the D2 event within NE-trending D2a tensile fractures, NW- to NNW-striking D2b normal faults and associated breccias, and NW- to NNW-striking D2c low-angle veins, with the latter D2b and D2c structures correlating to the Fimiston and Oroya mineralization types, respectively. All D2a-, D2b-, and D2c-related sulfides in the Golden Mile fault zone show similarly restricted δ34S (~1.0–4.5‰) and elevated Δ33S (~2.0–3.0‰) values that reflect strong local sulfur contribution from shales of the Lower Black Flag Group and host-rock buffering of hydrothermal fluids related to the Fimiston and Oroya mineralization events. This host-rock buffering decreased fluid fO2, favoring the development of pyrrhotite-pyrite stable sulfide assemblages and causing respective decreases and increases in fluid Au-Te and Pb-Bi-Sb concentrations. At the camp scale, the Golden Mile fault zone exerted a primary control on the distribution of porphyry dikes and gold deposits; however, magma and hydrothermal fluid circulation was favored in adjacent, higher-order structural sites due to the fault zone’s incompetent rheology and tendency for ductile deformation and diffuse fluid flow. Other Archean examples such as Au deposits of the Larder Lake-Cadillac deformation zone in the Superior craton illustrate that this type of diffuse fluid flow in large-scale crustal fault zones can result in disseminated economic mineralization. However, this study highlights that host-rock effects on fluid chemistry in large-scale crustal fault zones exercises a strong control on a fluid’s propensity to form ore. The results of this study emphasize that both the rheology and chemistry of rocks within and adjacent to large-scale deformation zones act as important controls on the formation of gold ore in Archean terranes.

Oleoylethanolamide Ameliorates Dextran Sulfate Sodium-Induced Colitis in Rats.

Oleoylethanolamide (OEA) is an endogenous fatty acid ethanolamide known for its anti-inflammatory effects and its influence on gut microbiota composition; however, the effects of OEA in inflammatory bowel disease (IBD) remain unknown. During in vitro experiments, OEA downregulated the expression of tumor necrosis factor (TNF)-α and reduced phosphorylation of inhibitor of kappa (Iκ) Bα induced by lipopolysaccharide in human embryonic kidney cells. Moreover, OEA downregulated the expression of interleukin (IL)-8 and IL-1β and inhibited the phosphorylation of IκBα and p65 induced by TNF-α in human enterocytes (Caco-2). The effect of OEA in reducing the expression of IL-8 was blocked by the peroxisome proliferator-activated receptor (PPAR)-α antagonist. During in vivo experiments on rats, colitis was induced by the oral administration of 8% dextran sulfate sodium from day 0 through day 5, and OEA (20 mg/kg) was intraperitoneally injected once a day from day 0 for 6 days. OEA administration significantly ameliorated the reduction in body weight, the increase in disease activity index score, and the shortening of colon length. In rectums, OEA administration reduced the infiltration of macrophages and neutrophils and tended to reduce the histological score and the expression of inflammatory cytokines. Administration of OEA produced significant improvement in a colitis model, possibly by inhibiting the nuclear factor kappa B signaling pathway through PPAR-α receptors. OEA could be a potential new treatment for IBD.

Unravelling the D1 event: evidence for early granite-up, greenstone-down tectonics in the Eastern Goldfields, Western Australia

The early tectonic history of the Eastern Goldfields Terrane (EGT) is poorly understood, but in places ca 2800 Ma mafic–ultramafic sequences are conformably overlain by ca 2720–2670 Ma sequences (e.g. Leonora and Laverton districts), suggesting minimal early deformation. The first significant angular unconformities occur at the base of the ca 2670–2655 Ma late basins and indicate that deformation was contemporaneous with deposition of the late basins. These basins mark the end of the volcano-sedimentary record in the EGT and typically grade upwards from polymictic mafic-dominated conglomerates to more siliciclastic compositions with abundant granitic clasts. The clastic sequences record the uplift and exhumation of granite-cored domes. There is a distinct lack of clasts with internal deformation fabrics (e.g. schist or gneiss). The timing of late basin formation overlaps with the ca 2672–2660 Ma D1 event, which has been variously described as extensional or compressional. D1 structures comprise a bedding-parallel S1 that is axial planar to F1 folds. The late basins and early D1 fabrics are overprinted by upright north-trending F2 folds and a sub-vertical S2. A period of crustal thickening was achieved by autochthonous processes with deposition of greenstone sequences into local basins between ca 2720 and 2670 Ma. Partial convective overturn (or granite-up, greenstone-down tectonics) developed as a result of gravitational instability. As the large granite–gneiss bodies rose, solid-state extensional D1 shears developed around the granites with a radial pattern of L1 extension lineations. Areas of compression developed within the sinking greenstone sequences. A final phase of subsidence in the central parts of the greenstone belts produced depocentres (late basins). A shift from dominantly vertical tectonics to horizontal tectonics at ca 2655–2650 Ma is marked by the onset of east–west D2 compression and the change in granite compositions from high-Ca to low-Ca granites. KEY POINTS Older ca 2800 Ma mafic–ultramafic sequences are conformably overlain by ca 2720–2670 Ma sequences suggesting minimal early deformation in the EGT. The first significant angular unconformities are at the base of the ca 2665 Ma late basin sequences. Late basin sequences record the uplift and exhumation of granite-cored domes and sedimentation is contemporaneous with the regional ca 2672–2660 Ma D1 event. The D1 event represents granite-up, greenstone-down tectonics (D1 event) that developed as a result of gravitational instability arising from autochthonous crustal thickening from ca 2720–2670 Ma. Granite-up, greenstone-down tectonics precludes an accretionary model for the development of the EGT.

Geometry and kinematics of brittle deformation in the Central Cameroon Shear Zone (Kékem area): Implication for gold exploration within the Central Africa Fold Belt in Cameroon

The Central Africa Fold Belt (CAFB) is a collision belt endowed with gold deposits in Eastern Cameroon area mined for about 50 years. However, favorable areas for gold exploration are poorly known. This paper presents (1) the kinematics of the brittle deformation in the Kékem area in the SW portion of the Central Cameroon Shear Zone and (2) constraints gold mineralization events with respect to the collisional evolution of the CAFB. The authors interpret that the conjugate ENE to E and NNW to NW trending lineament corresponds to the synthetic (R) and the antithetic (R’) shears, which accompanied the dextral slip along the NE to ENE striking shear. The latter coincides with the last 570–552 Ma D3 dextral simple shear-dominated transpression, which is parallel to the Bétaré Oya shear zone hosting gold deposits. Gold mineralizations, which mainly occurred during the last dextral shearing, are disseminated within quartz veins associated to Riedel’s previous structures reactivated due to late collisional activities of the CAFB as brittle deformation. Gold mineralizations occurred mainly during the 570–552 Ma D3 event. The reactivation, which might be due to dextral simple shear during mylonitzation, plausibly remobilized the early gold deposits hosted in syn-compressional rocks and/or possibly focused deep-sourced fluid mixed with those released by dehydration. Therefore, the Central Cameroon Shear Zone where Kékem is located, and which shows similar petrographical and structural features to those controling Batouri gold district, is a target area for gold exploration in Cameroon.

Inonotus obliquus polysaccharide protects against adverse pregnancy caused by Toxoplasma gondii infection through regulating Th17/Treg balance via TLR4/NF-κB pathway

The study aimed to explore the protective effects of Inonotus obliquus polysaccharide (IOP) on adverse pregnancy caused by Toxoplasma gondii (T. gondii) infection and discover its potential mechanisms in pregnant mice. Our data showed that IOP significantly reduced the abortion rate, inhibited the decreases of progesterone (P) and estriol (E3) levels and the increase of malondialdehyde (MDA) level, and increased the activities of superoxide dismutase (SOD) and glutathione (GSH). In addition, IOP inhibited the production of inflammatory cytokine tumor necrosis factor (TNF)-α, interleukin (IL)-6, interferon (IFN)-γ, IL-1β and IL-17A; and promoted the production of anti-inflammatory cytokine IL-10 and transforming growth factor (TGF)-β in T. gondii-infected pregnant mice. Furthermore, IOP effectively up-regulated the expression of forkhead box (Fox)p3, whereas down-regulated the expressions of retinoic acid-related orphan receptor (ROR)γt, signal transducer and activator of transcription (STAT)3 and toll-like receptor (TLR)4, and inhibited the phosphorylations of nuclear factor-κappaB (NF-κB) p65 and inhibitor kappa(Iκ)Bα in placental tissues with T. gondii-infected mice. These findings demonstrate that IOP exerts protective effects against adverse pregnancy caused by T. gondii infection in mice by promoting the balance of T helper (Th)17/regulatory T (Treg) through regulating TLR4/NF-κB pathway.

1α, 25-dihydroxyvitamin D3 inhibits tumor necrosis factor-α induced activation of human umbilical vein endothelial cells via NF-κB signaling pathway

Objective To investigate the effect of 1α, 25-dihydroxyvitamin D3[1α, 25-(OH)2D3] on tumor necrosis factor-α (TNF-α) induced activation of human umbilical vein endothelial cells (HUVECs). The mechanism involved in this process was also studied. Methods HUVECs were cultured and treated with TNF-α (40 ng/ml), 1α, 25-(OH)2D3(10-8 mol/L), and SN50 as indicated. Vascular cell adhesion molecule (VCAM) and E-selectin were used as markers of endothelial activation, which were detected by Western blotting and realtime PCR (RT-PCR). NF-κB signaling pathway was investigated to study the mechanism. Western blotting, RT-PCR, immunofluorescence assay, and chromatin immunoprecipitation (ChIP) method were used to evaluate the effects of 1α, 25-(OH)2D3 on its early activation, nuclear transport, and binding to VCAM and E-selectin promoters. Results (1)Western blotting and RT-PCR showed that TNF-α could significantly up-regulate the expression of VCAM and E-selectin in HUVECs, which can be inhibited by specific NF-κB blocker SN50. 1α, 25-(OH)2D3 down-regulated the expression of VCAM and E-selectin induced by TNF-α. (2) Western blotting showed that TNF-α induces I-κBα phosphorylation, thereby activating NF-κB p65 subunit. Immunofluorescence showed that 1α, 25-(OH)2D3 significantly inhibited the nuclear translocation of NF-κB p65 subunit. ChIP analysis revealed that 1α, 25-(OH)2D3 inhibited the binding of NF-κB p65 to VCAM and E-selectin promoters and thus affected gene expression. Conclusions TNF-α enhanced the expression of E-selectin and VCAM in HUVECs via NF-κB signaling pathway. 1α, 25-(OH)2D3 may inhibit NF-κB early activation, nuclear transport and the binding of NF-κB p65 to VCAM and E-selectin promoters, thereby inhibiting TNF-α-induced endothelial cell activation. Key words: 1α, 25-dihydroxyvitamin D3; Endothelial activation; NF-κB signaling pathway; Adhesion molecule

The Invincible deposit: Early gold mineralisation truncated by unaltered c. 2665 Ma conglomerate, St Ives, Eastern Goldfields, Western Australia

Two distinct styles of mineralisation are recognised at the Invincible deposit, with bedding-parallel shear related gold mineralisation (Type 1) and shallow-dipping mineralised extension veins (Type 2). The different styles of mineralisation reflect formation during two discrete deformation events.Type 1 mineralisation is hosted in laminated mudstone of the upper Black Flag Group and mineralised quartz veins and breccia zones are distributed throughout the mudstone rather than being associated with a single shear. Mineralised zones are associated with intense sodic alteration. The early mineralised structures are strongly modified by east-west horizontal D2-3 compression. In contrast, Type 2 extension veins are undeformed and are best developed in the massive sandstone-conglomerate footwall, but also overprint Type 1 veins in the mudstone unit.Throughout the mine, the early Type 1 mineralisation is truncated by unaltered conglomerate of the c. 2665 Ma Merougil Formation. A 10–20° difference in strike/dip is commonly present and indicates that the main mineralising event at Invincible occurred prior to erosion and deposition of the Merougil Formation. The strong modification of the mineralisation by horizontal east-west D2-3 compression is also consistent with formation early in the deformation history, during the c. 2672–2660 Ma D1 event. Gold deposition in the EGT was episodic, occurring over a prolonged period during extension and compression.Bedding-vein relationships indicate southwest-side-down kinematics during the early mineralising event. In weakly mineralised zones sub-vertical extension veins cut across beds that dip 70° to the southwest. In strongly mineralised zones, bedding is sub-vertical and large quartz breccia veins develop along the bedding above moderately west-dipping shears that extend across the steep bedding. The location of the steep strongly mineralised zones where bedding is sub-vertical reflects enhanced dilation in these zones during southwest-side-down movement.Southwest-side-down movement could represent extensional slip on the laminated mudstone beds if the bedding was tilted into a developing basin (early Merougil Basin). The location of the Invincible system, at the eastern edge of the Merougil Basin likely reflects an association with early basin-controlling faults.

Effect of electroacupuncture preconditioning on hippocampal IκB-α/NF-κB/ICAM-1 signaling pathway during cerebral ischemia-reperfusion in mice

Objective To evaluate the effect of electroacupuncture (EA) preconditioning on hippocampal I-kappa B-α (IκB-α)/nuclear factor κB (NF-κB)/intercellular adhesion molecule-1 (ICAM-1) signaling pathway during cerebral ischemia-reperfusion (I/R)in mice. Methods A total of 120 healthy male C57BL/6 mice, aged 10-12 weeks, weighing 20-25 g, were divided into 4 groups (n=30 each)using a random number table method: control group (group C), cerebral I/R group (group I/R), preconditioning with EA at non-acupoint + cerebral I/R group (group S+ I/R) and preconditioning with EA at Baihui acupoint + cerebral I/R group (group E+ I/R). The cerebral I/R injury model was established by occlusion of bilateral common carotid arteries followed by reperfusion for 72 h in mice anesthetized with halothane or chloral hydrate in group I/R.Group S+ I/R received EA at the points 2 mm lateral to the acupoints of Baihui for 5 consecutive days, and then the cerebral I/R injury model was established.Group E+ I/R received EA at Baihui acupoints with a sparse-dense wave at an intensity of 1 mA and a frequency of 2 Hz/15 Hz for 30 min once a day for 5 consecutive days, and then the cerebral I/R injury model was established.Neurobehavioral score was assessed at 24 and 48 h of reperfusion.Then 5 mice in each group were sacrificed, and the hippocampal tissues were obtained and stained with haematoxylin and eosin for examination of the pathological changes in hippocampal CA1 region and for determination of the expression of IκB-α, NF-κB, ICAM-1, interleukin-6 (IL-6), IL-1β protein and mRNA by Western blot and real-time polymerase chain reaction, respectively. Results Compared with group C, neurobehavioral score was significantly increased, and the expression of hippocampal IκB-α, NF-κB, ICAM-1, IL-6 and IL-1β protein and mRNA was up-regulated in I/R, S+ I/R and E+ I/R groups (P 0.05). Compared with group S+ I/R, neurobehavioral score was significantly decreased, and the expression of hippocampal IκB-α, NF-κB, ICAM-1, IL-6 and IL-1β protein and mRNA was down-regulated in group E+ I/R (P<0.05). Conclusion The mechanism by which EA preconditioning attenuates cerebral I/R injury may be related to inhibiting activation of hippocampal IκB-α/NF-κB/ICAM-1 signaling pathway in mice. Key words: Electroacupuncture; Ischemia preconditioning; Brain ischemia; Reperfusion injury; I-kappa B proteins; NF-kappa B; Intercellular adhesion molecule-1

Effect of Candida albicans on the production of interleukin-6 by and activation of IκBα in human THP-1 monocytes

Objective To investigate the effect of Candida albicans on the production of interleukin-6 by and activation of IκBα in an acute monocytic leukemia cell line THP-1.Methods THP-1 cells were classified into three groups to be stimulated by heat-killed C.albicans cells in concentrations of 105 and 106 colony-forming units (CFU)/ml and lipopolysaccharide (100 μg/L) in vitro respectively.Those remaining untreated served as the blank control group.After additional culture for different durations,real time reverse transcription PCR and enzyme-linked immunosorbent assay were performed to measure the mRNA and protein expression levels of interleukin-6 (IL-6) respectively,and Western blot was conducted to determine the levels of total and phosphorylated IκBα.Statistical analysis was carried out by t test.Results A significant increase was observed in the mRNA expression level (2-△△α) of IL-6 in THP-1 cells at 3 and 6 hours after starting treatment with C.albicans at 105 CFU/ml (6.48 ± 0.30 vs.0.84 ± 0.16,125.34 ± 1.47 vs.1.22 ± 0.22,both P ＜ 0.01),and at 1,3 and 6 hours after starting treatment with C.albicans at 106 CFU/ml (2.96 ± 0.35 vs.1.03 ± 0.16,8.57 ± 1.27 vs.0.84 ± 0.16,588.10 ± 2.31 vs.1.22 ± 0.22,P＜ 0.05 or 0.01) compared with the blank control group,but no significant difference was noted between THP-1 cells at 1 hour after starting treatment with C.albicans at 105 CFU/ml and those remaining untreated (1.48 ± 0.06 vs.1.03 ± 0.16,P＞ 0.05).The protein expression level of IL-6 was (924.9 ± 30.13) ng/L in THP-1 cells at 24 hours after starting treatment with C.albicans at 106 CFU/ml,significantly different from that in the blank control group (P ＜ 0.001).There was a marked elevation in the level of phosphorylated IκBα protein,but an obvious reduction in the level of IκBα protein in THP-1 cells treated with C.albicans at 106 CFU/ml for 30 and 60 minutes.Conclusion Human THP-1 monocytes may play a role in innate immune responses against C.albicans through activation of nuclear factor-κB and production of IL-6. Key words: Candida albicans; Leukemia, monocytic, acute; Interleukin-6; I-kappa B proteins; NF-kappa B

Protective effect of thymosin β4 on severe acute pancreatitis in rats

Objective To investigate the protective effects and mechanisms of intraperitoneal administration of thymosin β4 on severe acute pancreatitis in rats.Methods Fifty-four male Sprague-Dawley rats were randomly (random number) divided into sham operation (SO) group,severe acute pancreatitis (SAP) group and thymosin β4 (Tβ4) pretreatment group (n =18 in each group).SAP rat model was prepared by retrograde injection of 5％ sodium taurocholate into the biliopancreatic duct.Rats in Tβ4 group were treated with thymosin β4 (6 mg/kg) by intraperitoneal administration prior to SAP modeling.Six rats in each group were sacrificed at 3,6,12 hours,respectively after modeling.The serum levels of amylase,tumor necrosis factor-α (TNF-α),interleukin-1 β (IL-1 β),and interleukin-6 (IL-6)were detected,and pathological scores of the tissue of pancreas head were evaluated under light microscope.Pancreatic nuclear factor-kappa 1B (NF-κB) p65 and IκB α levels were detected by the Western blot.All data were analyzed by using the analysis of variauce or t test.Results The levels of serum amylase of SAP 3,6 and 12 hours groups were (3221 ±394) U/L,(4509 ±474) U/L and (6280 ±728) U/L,which were significantly higher than (2598±416) U/L,(3639 ±373) U/L and (4782 ±466) U/L of the Tβ4 groups (t =-2.666,-3.530,-4.245,P ＜ 0.05).The levels of serum TNF-α of the SAP 3,6 and 12 hours groups were (247.7 ± 18.5) pg/mL,(313.5 ± 17.7) pg/mL and (359.3 ±22.6) pg/mL,which were higher than (182.3 ± 13.6) pg/mL,(258.9 ± 14.9) pg/mL and (278.1 ± 16.3) pg/mL of the Tβ4 groups (t =-6.964,-5.769,-7.152,P ＜ 0.05).The levels of serum IL-1 β of the SAP 3,6 and 12 hours groups were (258.2±10.5) pg/mL,(345.1 ±22.0) pg/mL and (430.9 ±25.4) pg/mL,which were higher than (170.3 ± 12.4) pg/mL,(263.5 ± 13.3) pg/mL and (303.7 ± 16.1) pg/mL of the Tβ4 groups (t =-13.258,-7.762,-10.355,P ＜ 0.05).The levels of serum IL-6 of SAP 3,6 and 12 hours groups were (266.3 ±11.5) pg/mL,(355.0 ±24.4) pg/mL and (429.2 ±33.7) pg/ mL,which were higher than (171.1 ± 13.0) pg/mL,(234.9 ± 19.2) pg/mL and (277.2 ± 19.2) pg/ mL of the Tβ4 groups (t =-13.401,-9.474,-9.582,P ＜ 0.05).The pancreatic pathological scores of the SAP3,6 and 12 hours groups were (6.25 ±0.94),(8.83 ±0.82) and (12.08 ±1.16),which were higher than (4.17 ± 0.93),(6.33 ± 0.82) and (7.33 ± 1.25) of the Tβ4 groups (t =-3.867,-5.303,-6.823,P ＜ 0.05).The relative expression of pancreatic NF-κB p65 in SO group was (0.95 ±0.11),which was significantly lower than (2.40 ±0.17) of the SAP 12 hours group (t =-17.368,P＜ 0.05).The relative expression of pancreatic NF-κB p65 in Tβ4 group was 1.50 ± 0.10,which was significantly lower than SAP 12 hours group (t =10.917,P ＜0.05).The relative expression of pancreatic IκB α in SO group was (1.93 ±0.11),which was significantly higher than (0.78 ±0.18) of the SAP 12 hours group (t =13.260,P ＜ 0.05).The relative expression of pancreatic IκB α in Tβ4 group was (1.12±0.10),which was significantly higher than SAP 12 hours group (t =-4.112,P ＜ 0.05).Conclusions Thymosin β4 has the protective effect on SAP rat model,and the mechanism may be associated with inhibition of NF-κB signaling pathway and decreased proinflammatory cytokines. Key words: Acute abdomen; Pancreatitis; Thymosin β4; Tumor necrosis factor-α; Cell Signaling Pathway; Nuclear factor-kappa B; Actin; Systemic inflammatory response syndrome; Multiple organ dysfunction syndrome

Role of progesterone in TLR4-MyD88-dependent signaling pathway in pre-eclampsia

The role of progesterone in the Toll-like receptor 4 (TLR4)-MyD88-dependent signaling pathway in pre-eclampsia was studied. Peripheral blood mononuclear cells (PBMCs) from pre-eclampsia (PE) patients were subjected to primary culture, and stimulated with different concentrations of progesterone (0, 10(-8), 10(-6), and 10(-4) mol/L). The mRNA expression of TLR4, MyD88 and nuclear factor-kappaB (NF-κB) was detected by using real-time PCR. The Ikappa-B protein expression was detected by using Western blotting. The expression of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the supernatant was determined by using ELISA. With the concentrations of progesterone increasing, the mRNA expression levels of TLR4, MyD88 and NF-κB in 2(-ΔΔCT) value were significantly decreased, and the IkappaB protein expression levels were significantly increased. The TNF-α and IL-6 expression showed a downward trend when the progesterone concentration increased, and there were significant differences among all of the groups (P<0.05). It was suggested that progesterone can inhibit the TLR4-MyD88-dependent signaling pathway in PE significantly and benefit for the pregnancy.

Effect of exogenous hydrogen sulfide on myocardial NF-κB signaling pathway in rats with hemorrhagic shock

Objective To investigate the effect of exogenous hydrogen sulfide on myocardial NF-kB sig- naling pathway in rats with hemorrhagic shock （HS） .Methods Forty adult male rats, weighing 250-300 g, were randomly divided into 4 groups （ n = 10 each） ： sham operation group （Sham group）, sham operation ＋ NariS group （Sham ＋ NariS group）, HS group and HS ＋ NariS group. HS was induced by withdrawing blood from the femoral artery. After HS, NariS 28 μmol/kg was injected intraperitoneally at 10 min before resuscitation in groups HS ＋ NariS and Sham ＋ NariS. MAP was monitored and recorded at 0, 1.5, 2, 3, 4 and 6 h after blood-letting. The rats were then sacrificed and hearts were removed for determination of phosphorylated IKKβ （pIKKβ）, IkBa （pIkBa）, NF-kB p65 （pNF-kB p65） and high-mobility group box 1 （HMGB1） and for examination of myocardial ultrastructure with light arid electron microscope. Results Compared with Sham and Sham ＋ NaSH groups, MAP was significantly decreased and the expression of pIKKβ, pIkBa, pNF-kB p65 and HMGB1 was up-regulated in HS and HS ＋ Naris groups （ P 〈 0.05）. Compared with HS group, MAP was significantly increased and the expres- sion of pIKKβ, pIkBa, pNF-kB p65 and HMGB1 was down-regulated in HS ＋ NariS group （P 〈 0.05）. The pathologic changes were attenuated in HS ＋ NariS group compared with group HS. Conclusion Exogenous hydro- gen sulfide can attenuate myocardial injury induced by HS through inhibition of NF-kB signaling pathway and re- duction of inflammatory response. Key words: Hydrogen sulfide; Shock,hemorrhagic; Myocardial reperfusion injury; NF-kappa B

Mad1 attachment

Mad1 attachment

Structural and geochronological constraints on the Mesozoic‐Cenozoic tectonic evolution of the Longmen Shan thrust belt, eastern Tibetan Plateau

The Longmen Shan thrust belt in the eastern margin of the Tibetan Plateau underwent deformation of D1 associated with the Late Triassic collision between the North and South China Blocks, followed by deformation of D2 and D3 related to the eastward growth of the Tibetan Plateau. The D1 is marked by moderately tight folds (f1), spaced cleavage (S1), mineral lineation (L1), multistage reactivated faults, and top‐to‐the south thrusting. This deformation initiated before 237 Ma and ended at 208 Ma. The 193–159 Ma D2 deformation is top‐to‐the‐southeast directed and normal ductile in nature and was associated with the formation of half‐graben basins. The Mesozoic deformation of the Longmen Shan belt was related to the subduction of the Paleo‐Tethys oceanic lithosphere, followed by the South China Block underneath the Songpan‐Ganze Terrane. The D1 was produced in the pro‐side of the overriding Songpan‐Ganze plate, most probably driven by slab corner flow above the retreating South China Block. The D2 and extensional Songpan‐Ganze turbidite basin were produced by roll‐back and migration of the overriding plate above the retreating subduction zone. This model for the deformation from D1 to D2 is similar to a Mediterranean‐style model. The D3 is characterized by SE‐ward thrusting with stepwise migration of rapid denudation and dextral strike‐slip faulting during the Late Cretaceous to present. Therefore, the Longmen Shan thrust belt involved Mesozoic compressional and extensional events that were overprinted by the Late Cretaceous to Cenozoic compressional event.