Characteristics and Transformation Mechanism of Nonmetallic Inclusions in 304 Stainless Steel during Heat Treatment at 1250 °C

Evolutions of two typical types of nonmetallic inclusions, i.e., inclusions based on CaO-SiO₂-Al₂O₃ and MnO-SiO₂-Al₂O₃ of 304 stainless steel were investigated in laboratory-scale experiments under isothermal heat treatment at 1250 °C for 0, 30, 60 and 120 min. Results show inclusion population density increases at the first stage and then decreases while their average size decreases and then increases. Moreover, almost no Cr₂O₃ content within the inclusion before the heat treatment, but Cr₂O₃ content increases gradually along with increasing heat treatment time. Furthermore, the increasing of Cr₂O₃ content in the inclusions would increase their melting points and reduce their plasticities. The experimental results and thermodynamic analysis indicate that there are three steps for inclusion evolution during the heat treatment process, in which Ostwald ripening plays an important role in inclusion evolution, i.e., inclusions grow by absorbing the newly formed small-size MnO-Cr₂O₃ inclusions.     

A Novel Micro-Displacement Sensor Based on Double Optical Fiber Probes Made through Photopolymer Materials

In this paper, a novel micro-displacement sensor with double optical fiber probes is proposed and designed, which can realize the highly sensitive sensing of longitudinal or lateral micro-displacements. The optical fiber probes are made through photopolymer formulation, and the effects of reaction time and optical power on the growth length of the probe are illustrated. The relationship between light intensity and longitudinal micro-displacement is a power function in the range of 0–100 μm at room temperature with a correlation coefficient of 98.92%. For lateral micro-displacement, the sensitivity is −2.9697 dBm/μm in the range of 0–6 μm with a linear fit of 99.61%. In addition, the linear correlation coefficient decreases as the initial longitudinal distance increases, and the function of these correlation coefficients is also linear with a linearity of 96.14%. This sensor has a simple manufacturing process, low cost, high sensitivity, and fast response speed. It is suitable for harsh environments such as strong electromagnetic interference and corrosivity, and has a broad application prospect in the field of micro-displacement sensing.     

Prognostic Indicators for Acute Liver Failure Development and Mortality in Patients with Hepatitis A: Consecutive Case Analysis

Purpose

Due to the seroepidemiological shift in hepatitis A (HA), its severity, mortality, and complications have increased in recent years. Thus, the aim of this study was to identify predictive factors associated with poor prognosis among patients with HA.

Materials and Methods

A total of 304 patients with HA admitted to our institution between July 2009 and June 2011 were enrolled consecutively. Patients with complications defined as acute liver failure (ALF) were evaluated, and mortality was defined as death or liver transplantation.

Results

The mean age of patients (204 males, 100 females) was 32 years. Eighteen (5.9%) patients had progressed to ALF. Of the patients with ALF, 10 patients (3.3%) showed spontaneous survival while 8 (2.6%) died or underwent liver transplantation. Multivariate regression analysis showed that Model for End-Stage Liver Disease (MELD) and systemic inflammatory response syndrome (SIRS) scores were significant predictive factors of ALF. Based on receiver operating characteristics (ROC) analysis, a MELD ≥23.5 was significantly more predictive than a SIRS score ≥3 (area under the ROC: 0.940 vs. 0.742, respectively). In addition, of patients with a MELD score ≥23.5, King''s College Hospital criteria (KCC) and SIRS scores were predictive factors associated with death/transplantation in multivariate analysis.

Conclusion

MELD and SIRS scores ≥23.5 and ≥3, respectively, appeared to be related to ALF development. In addition, KCC and SIRS scores ≥3 were valuable in predicting mortality of patients with a MELD ≥23.5.     

Gomisin A decreases the LPS-induced expression of iNOS and COX-2 and activation of RIP2/NF-κB in mouse peritoneal macrophages

Gomisin A (GA), a lignan component contained in the fruit of Schisandra chinensis Baillon, improves hepatic cell degeneration, vasodilatory activity and insulin sensitivity. These effects also impact the immune system, including various inflammatory mediators and cytokines. In this study, the anti-inflammatory effect of GA on lipopolysaccharide-stimulated mouse peritoneal macrophages was studied. Pretreatment with GA attenuated the expression of receptor-interacting protein 2 (RIP2) and IκB kinase-β (IKK-β) as well as IKK-β phosphorylation. The activation of nuclear factor-kappa B (NF-κB) in the nucleus, the phosphorylation of IκBα and degradation of IκBα in the cytosol were suppressed by GA. GA decreased the production and mRNA expression of the inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6. In addition, expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and production of nitric oxide were decreased by pretreatment with GA. In conclusion, these results show that the anti-inflammatory properties of GA potentially result from the inhibition of COX-2, iNOS, IL-6, TNF-α and NO through the down-regulation of RIP2 and NF-κB activation. These results impact the development of potential health products for preventing and treating inflammatory diseases.     

Development of a radiopaque,long-term drug eluting bioresorbable stent for the femoral-iliac artery

Tubular tissues exist in various forms purported for blood supply, waste secretion, etc. to aid proper function and maintenance of the human body. Under pathological conditions, however, these tissues may undergo stenosis. A major surgical treatment for stenosis is to implant a medical device called a stent which aims to expand the narrowed tissue and maintain its patency. Most stents are currently made from metals; despite their high mechanical strength, however, interactions with the host tissue often results in restenosis and stent fracture. To solve these problems, a bioresorbable stent (BRS) is proposed as a next generation stent. In this study, a rotating rod combined 3D printing system was developed to fabricate various types of BRSs. In addition, we confirmed that a 1.5 year long-term release of paclitaxel is possible using polymeric materials. Moreover, a stent loaded with contrast powder was fabricated and was successfully viewed under fluoroscopy. The stent was then implanted in the iliac arteries of pigs and no adverse events were observed for up to 8 weeks.

A radiopaque, long-term drug eluting bioresorbable stent is developed for the treatment of femoral-iliac artery. The prepared materials are printed on a pre-designed rotating rod. The fabricated stent can be adapted for various clinical cases.     

Cone beam CT findings of retromolar canals in a Korean population

Purpose

The identification of the variation involving the mandibular canal is important during surgical procedures in the mandible. This study aims to investigate the incidence, course, width, and location of retromolar canals in a Korean population using cone beam CT.

Methods

The cross-sectional, sagittal, and three dimensional images from volumetric cone beam CT data of 446 patients were reconstructed using imaging analysis software for the presence of a retromolar canal. Retromolar canals were classified into three types according to the courses. The width and location (distance from the second molar) of retromolar canals were evaluated.

Results

A retromolar canal was observed in 8.5 % of patients (38/446). Most retromolar canals had vertically curved courses (Type 1, 66.7 %), followed by horizontally curved courses (Type 2, 20 %). Type 3 retromolar canals, which run independently from separate foramina in the mandibular ramus, were rare (13.3 %). The mean width of a retromolar canal was 1.13 mm (SD ± 0.38, 0.60–2.00), and the mean distance to the second molar was 14.08 mm (SD ± 3.85, 8.50–24.00).

Conclusions

The incidence of retromolar canals in the Korean population was lower than that reported in the investigated ethnic groups. In the presence of a retromolar canal, local anesthesia may be ineffective. The damage to a retromolar canal may be unavoidable during surgical procedures involving the mandible and may result in paresthesia, excessive bleeding, postoperative hematoma, or traumatic neuroma.     

Correction: A highly selective fluorescent probe for human NAD(P)H:quinone oxidoreductase 1 (hNQO1) detection and imaging in living tumor cells

Correction for ‘A highly selective fluorescent probe for human NAD(P)H:quinone oxidoreductase 1 (hNQO1) detection and imaging in living tumor cells’ by Ya Zhu et al., RSC Adv., 2019, 9, 26729–26733.

The authors regret that some articles reporting probes for detecting human NAD(P)H:quinone oxidoreductase 1 were not cited in the original article. The missing references are listed below as ref. 1–6, and should be cited in the original paper at the end of the following sentence on page 26729:Herein, we designed and synthesized a novel fluorescent probe 1 for detection of hNQO1 based on TCF-OH as a chromophore and quinone propionic acid (QPA) as a recognition group.^1–6The authors sincerely apologise for this oversight.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.     

Blockade of the T cell immunoglobulin and mucin domain protein 3 pathway exacerbates sepsis-induced immune deviation and immunosuppression

Sepsis is a life-threatening condition, but the pathophysiological basis and biomarkers for the monitoring of sepsis and as targets for therapy remain to be determined. We have shown previously that T cell immunoglobulin and mucin domain protein 3 (Tim-3), a negative immune regulator, is involved in the physiopathology of sepsis, but the underlying mechanisms remain unclear. In the present study, we showed that Tim-3 signalling modulated the response patterns of both macrophages and T helper cells in sepsis. Blockade of the Tim-3 pathway exacerbated sepsis-induced proinflammatory macrophage responses and lymphocyte apoptosis during the early phase of sepsis, and enhanced the shift to anti-inflammatory responses for both macrophages and T helper cells during the late phase of sepsis. Tim-3 signalling was found to regulate CD80 and CD86 expression on macrophages both in vivo and in vitro. Co-culture of T cells with Tim-3 knock-down macrophages led to a biased T helper type 2 (Th2) response, partially explaining how Tim-3 signalling shapes inflammation patterns in vivo. Further studies on this pathway might shed new light on the pathogenesis of sepsis and suggest new approaches for intervention.     

Sphingosine‐1‐phosphate receptor 1 signalling in T cells: trafficking and beyond

Sphingosine-1-phosphate (S1P) is a lipid second messenger that signals via five G protein-coupled receptors (S1P_1–5). S1P receptor (S1PR) signalling is associated with a wide variety of physiological processes including lymphocyte biology, their recirculation and determination of T-cell phenotypes. The effect of FTY720 (Fingolimod, Gilenya™) to regulate lymphocyte egress and to ameliorate paralysis in experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis led to the use of FTY720 as a first-line oral agent for treatment of relapsing–remitting multiple sclerosis. However, a significant body of research suggests that S1P signalling may participate in diverse immune regulatory functions other than lymphocyte trafficking. This review article discusses the current knowledge of S1P signalling in the fate and function of T regulatory, T helper type 17 and memory T cells in health and disease.