166 research outputs found
Nano-mechanical properties of Fe-Mn-Al-C lightweight steels
High Al Low-density steels could have a transformative effect on the light-weighting of steel structures for transportation and achieving the desired properties with the minimum amount of Ni is of great interest from an economic perspective. In this study, the mechanical properties of two duplex low-density steels, Fe-15Mn-10Al-0.8C-5Ni and Fe-15Mn-10Al-0.8C (wt.%) were investigated through nano-indentation and simulation through utilization of ab initio formalisms in Density Functional Theory (DFT) in order to establish the hardness resulting from two critical structural features (ߢ-carbides and B2 intermetallic) as a function of annealing temperature (500 − 1050 ℃) and the addition of Ni. In the Ni-free sample, the calculated elastic properties of kappa-carbides were compared with those of the B2 intermetallic Fe3Al − L12, and the role of Mn in the kappa structure and its elastic properties were studied. The Ni-containing samples were found to have a higher hardness due to the B2 phase composition being NiAl rather than FeAl, with Ni-Al bonds reported to be stronger than the Fe-Al bonds. In both samples, at temperatures of 900 ℃ and above, the ferrite phase contained nano-sized discs of B2 phase, wherein the Ni-containing samples exhibited higher hardness, attributed again to the stronger Ni-Al bonds in the B2 phase. At 700 ℃ and below, the nano-sized B2 discs were replaced by micrometre sized needles of kappa in the Ni-free sample resulting in a lowering of the hardness. In the Ni-containing sample, the entire alpha phase was replaced by B2 stringers, which had a lower hardness than the Ni-Al nano-discs due to a lower Ni content in B2 stringer bands formed at 700 ℃ and below. In addition, the hardness of needle-like kappa-carbides formed in alpha phase was found to be a function of Mn content. Although it was impossible to measure the hardness of cuboid kappa particles in gamma phase because of their nano-size, the hardness value of composite phases, e.g. gamma + kappa was measured and reported. All the hardness values were compared and rationalized by bonding energy between different atoms
Ramosetron versus Palonosetron in Combination with Aprepitant and Dexamethasone for the Control of Highly-Emetogenic Chemotherapy-Induced Nausea and Vomiting
PURPOSE: The purpose of this study was to compare ramosetron (RAM), aprepitant (APR), and dexamethasone (DEX) [RAD] with palonosetron (PAL), APR, and DEX [PAD] in controlling highly-emetogenic chemotherapy (HEC)-induced nausea and vomiting.
MATERIALS AND METHODS: Patients were randomly assigned (1:1) to receive RAD or PAD:RAM (0.3 mg intravenously) or PAL (0.25 mg intravenously) D1, combined with APR (125 mg orally, D1 and 80 mg orally, D2-3) and DEX (12 mg orally or intravenously, D1 and 8 mg orally, D2-4). Patients were stratified by sex, cisplatin-based chemotherapy, and administration schedule. The primary endpoint was overall complete response (CR), defined as no emesis and no rescue regimen during 5 days of HEC. Secondary endpoints were overall complete protection (CP; CR+nausea score < 25 mm) and total control (TC; CR+nausea score < 5 mm). Quality of life was assessed by Functional Living Index Emesis (FLIE) questionnaire on D0 and D6.
RESULTS: A total of 279 patients receiving RAD (n=137) or PAD (n=142) were evaluated. Overall CR rates in RAD and PAD recipients were 81.8% and 79.6% (risk difference [RD], 2.2%; 95% confidence interval [CI], -7.1 to 11.4), respectively. Overall CP and TC rates for RAD and PAD were 56.2% and 58.5% (RD, -2.3%; 95% CI, -13.9 to 9.4) and 47.5% vs. 43.7% (RD, 3.8%; 95% CI, -7.9 to 15.5), respectively. FLIE total score >/= 108 (no impact on daily life) was comparable between RAD and PAD (73.9% vs. 73.4%, respectively). Adverse events were similar between the two groups.
CONCLUSION: In all aspects of efficacy, safety and QOL, RAD is non-inferior to PAD for the control of CINV in cancer patients receiving HEC
Change in hardness of an as-cast and softening heat-treated low-gold-content alloy for bonding porcelain by simulated porcelain firing and its mechanism
Clinical significance of soft markers in second trimester ultrasonography for pregnant Korean women: a multicenter study and literature review
OBJECTIVE: To evaluate the clinical significance of soft markers for aneuploidy screening in Korean women. METHODS: We retrospectively reviewed the medical records of 5,428 singleton pregnant women who underwent sonography during the second trimester at seven institutions in South Korea. We evaluated the prevalence of the following soft markers: intracardiac echogenic focus, choroid plexus cysts, pyelectasis, echogenic bowel, and mild ventriculomegaly. We developed best-fitted regression equations for the fetal femur and humerus length using our data and defined a short femur and humerus as both long bones below the fifth centile. The results of genetic testing and postnatal outcomes were investigated in patients who had been diagnosed with aforementioned soft markers. RESULTS: The median maternal age of our study population was 33 years, and the median gestational age at the time of ultrasonographic examination was 21 weeks. We detected soft markers in 10.0% (n=540) of fetuses: 9.3% (n=504) were isolated cases and 0.7% (n=36) of cases had two or more markers. We identified only two aneuploides (trisomy 18, 46,XX,t[8;10][q22.1;p13]), of which one was clinically significant. We presented the neonatal outcomes of the fetuses with the respective soft markers. Preterm delivery, low birth weight, and small-for-gestational-age (SGA) were significantly more common in women with a shortened fetal femur (P<0.001, all). However, the presence of a shortened fetal humerus was not associated with those outcomes excluding SGA. CONCLUSION: Soft markers in second-trimester ultrasonography have limited use in screening for fetal aneuploidy in Korean women. However, these markers can be used as a screening tool for adverse outcomes other than chromosomal abnormality
Summary of clinically diagnosed amniotic fluid embolism cases in Korea and disagreement with 4 criteria proposed for research purpose
Objective: This study aimed 1) to investigate the clinical characteristics of amniotic fluid embolism (AFE) cases clinically diagnosed by maternal fetal medicine (MFM) specialists in Korea, 2) to check the disagreement with 4 recently proposed criteria by the Society for Maternal-Fetal Medicine (SMFM) for research purpose, and 3) to compare maternal outcomes between cases satisfying all 4 criteria and cases with at least 1 missing criterion. Methods This study included 12 patients clinically diagnosed with AFE from 7 referral hospitals in Korea. We collected information, including maternal age, symptoms of AFE, the amount of transfusion, and maternal mortality. Results The median maternal age was 33 years (range, 28-40 years). Regarding symptoms, cardiovascular arrest, hypotension, respiratory compromise, clinical coagulopathy, and neurologic signs were observed in 41.7%, 83.3%, 83.3%, 100%, and 66.7% of the cases, respectively. Among the 12 cases, 5 women died and 2 suffered severe neurologic disability, showing an intact survival rate of 41.7%. Disagreement with all 4 criteria proposed by the SMFM was found in 66.7% of the cases, due to the lack of criteria for disseminated intravascular coagulation or strict onset time (<30 minutes after delivery). There was no difference in maternal mortality and the amount of transfusion between cases satisfying all 4 criteria and cases with at least 1 missing criterion. Conclusion Two-thirds of clinically confirmed AFE cases did not satisfy all 4 criteria proposed by the SMFM, despite similar rates of maternal mortality with cases satisfying all 4 criteria. Our study suggests that there may be some discrepancy between the clinical diagnosis of AFE and the recent diagnostic criteria proposed by the SMFM for research purpose
Ultrasonographic assessment of abnormal fetal growth related to uteroplacental-fetal biometrics and Doppler (U-AID) indices: Protocol for multicenter retrospective cohort study trial
Fetal growth restriction (FGR) is one of the leading causes of perinatal morbidity and mortality. Many studies have reported an association between FGR and fetal Doppler indices focusing on umbilical artery (UA), middle cerebral artery (MCA), and ductus venosus (DV). The uteroplacental-fetal circulation which affects the fetal growth consists of not only UA, MCA, and DV, but also umbilical vein (UV), placenta and uterus itself. Nevertheless, there is a paucity of large-scale cohort studies that have assessed the association between UV, uterine wall, and placental thickness with perinatal outcomes in FGR, in conjunction with all components of the uteroplacental-fetal circulation. Therefore, this multicenter study will evaluate the association among UV absolute flow, placental thickness, and uterine wall thickness and adverse perinatal outcome in FGR fetuses. This multicenter retrospective cohort study will include singleton pregnant women who undergo at least one routine fetal ultrasound scan during routine antepartum care. Pregnant women with fetuses having structural or chromosomal abnormalities will be excluded. The U-AID indices (UtA, UA, MCA, and UV flow, placental and uterine wall thickness, and estimated fetal body weight) will be measured during each trimester of pregnancy. The study population will be divided into two groups: (1) FGR group (pregnant women with FGR fetuses) and (2) control group (those with normal growth fetus). We will assess the association between U-AID indices and adverse perinatal outcomes in the FGR group and the difference in U-AID indices between the two groups
Randomized, Controlled, Multi-center Trial: Comparing the Safety and Efficacy of DA-9701 and Itopride Hydrochloride in Patients With Functional Dyspepsia.
BACKGROUND/AIMS: Therapies of functional dyspepsia (FD) are limited. DA-9701 is a novel prokinetic agent formulated with Pharbitis semen and Corydalis Tuber. We aimed to assess the efficacy of DA-9701 compared with itopride in FD patients.
METHODS: Patients with FD randomly received either itopride 50 mg or DA-9701 30 mg t.i.d after a 2-week baseline period. After 4 weeks of treatment, 2 primary efficacy endpoints were analyzed: the change from baseline in composite score of the 8 dyspep-tic symptoms and the overall treatment effect. Impact on patients' quality of life was assessed using the Nepean Dyspepsia Index (NDI) questionnaire.
RESULTS: We randomly assigned 464 patients with 455 having outcome data. The difference of the composite score change of the 8 symptoms between the 2 groups was 0.62, indicating that DA-9701 was not inferior to itopride. The overall treatment effect response rate was not different between the groups. When responder was defined as ≥ 5 of the 7 Likert scale, responder rates were 37% of DA-9701 and 36% of itopride group. Patients receiving DA-9701 experienced similar mean percentage of days with adequate relief during the 4-week treatment period compared with those receiving itopride (56.8% vs 59.1%). Both drugs increased the NDI score of 5 domains without any difference in change of the NDI score between the groups. The safety profile of both drugs was comparable.
CONCLUSIONS: DA-9701 significantly improves symptoms in patients with FD. DA-9701 showed non-inferior efficacy to itopride with com-parable safety
Addition of Cervical Elastography May Increase Preterm Delivery Prediction Performance in Pregnant Women with Short Cervix: a Prospective Study
BACKGROUND: We investigated whether there is a difference in elastographic parameters between pregnancies with and without spontaneous preterm delivery (sPTD) in women with a short cervix (</= 25 mm), and examined the ability of elastographic parameters to predict sPTD in those women.
METHODS: E-Cervix(TM) (WS80A: Samsung Medison, Seoul, Korea) elastography was used to examine the cervical strain. Elastographic parameters were compared between pregnancies with and without sPTD. Diagnostic performance of elastographic parameters to predict sPTD </= 37 weeks, both alone and in combination with other parameters, was compared with that of cervical length (CL) using area under receiver operating characteristic curve (AUC) analysis.
RESULTS: A total of 130 women were included. Median gestational age (GA) at examination was 24.4 weeks (interquartile range, 21.4-28.9), and the prevalence of sPTD was 20.0% (26/130). Both the elastographic parameters and CL did not show statistical difference between those with and without sPTD. However, when only patients with CL >/= 1.5 cm (n = 110) were included in the analysis, there was a significant difference between two groups in elasticity contrast index (ECI) within 0.5/1.0/1.5 cm from the cervical canal (P /= 1.5 cm, the combination of parameters (CL + pre-pregnancy body mass index + GA at exam + ECI within 0.5/1.0/1.5 cm) showed a significantly higher AUC than CL alone (P < 0.05).
CONCLUSION: An addition of cervical elastography may improve the ability to predict sPTD in women with a short CL between 1.5 and 2.5 cm
Effect of Cervical Cerclage on the Risk of Recurrent Preterm Birth after a Twin Spontaneous Preterm Birth
BACKGROUND: This study aimed to evaluate the effect of cervical cerclage on the recurrence risk for preterm birth in singleton pregnant women after a twin spontaneous preterm birth (sPTB). METHODS: This multicenter retrospective cohort study included women who had a singleton pregnancy from January 2009 to December 2018 at 10 referral hospitals and a twin sPTB before the current pregnancy. We compared the cervical lengths during pregnancy and pregnancy outcomes, according to the placement of prophylactic or emergency cerclage. We evaluated the independent risk factors for sPTB (< 37 weeks of gestation) in a subsequent singleton pregnancy. RESULTS: For the index singleton pregnancy, preterm birth occurred in seven (11.1%) of 63 women. There was no significant difference in the cervical lengths during pregnancy in women with and without cerclage. In a multivariate logistic regression analysis, the placement of emergency cerclage was an independent risk factor for subsequent singleton preterm birth (odds ratio [OR], 93.188; 95% confidence interval [CI], 1.633-5,316.628; P = 0.027); however, the placement of prophylactic cerclage (OR, 19.264; 95% CI, 0.915-405.786; P = 0.057) was not a factor. None of the women who received prophylactic cerclage delivered before 35 weeks' gestation in the index singleton pregnancy. CONCLUSION: Cerclage did not lower the risk of preterm birth in a subsequent singleton pregnancy after a twin sPTB. However, emergency cerclage was an independent risk factor for preterm birth and there was no preterm birth before 35 weeks' gestation in the prophylactic cerclage group. Therefore, close monitoring of the cervical length and prophylactic cerclage might be considered in women who have experienced a twin sPTB at extreme gestation
Rare Exonic Minisatellite Alleles in MUC2 Influence Susceptibility to Gastric Carcinoma
BACKGROUND: Mucins are the major components of mucus and their genes share a common, centrally-located region of sequence that encodes tandem repeats. Mucins are well known genes with respect to their specific expression levels; however, their genomic levels are unclear because of complex genomic properties. In this study, we identified eight novel minisatellites from the entire MUC2 region and investigated how allelic variation in these minisatellites may affect susceptibility to gastrointestinal cancer. METHODOLOGY/PRINCIPLE FINDINGS: We analyzed genomic DNA from the blood of normal healthy individuals and multi-generational family groups. Six of the eight minisatellites exhibited polymorphism and were transmitted meiotically in seven families, following Mendelian inheritance. Furthermore, a case-control study was performed that compared genomic DNA from 457 cancer-free controls with DNA from individuals with gastric (455), colon (192) and rectal (271) cancers. A statistically significant association was identified between rare exonic MUC2-MS6 alleles and the occurrence of gastric cancer: odds ratio (OR), 2.56; 95% confidence interval (CI), 1.31-5.04; and p = 0.0047. We focused on an association between rare alleles and gastric cancer. Rare alleles were divided into short (40, 43 and 44) and long (47, 50 and 54), according to their TR (tandem repeats) lengths. Interestingly, short rare alleles were associated with gastric cancer (OR = 5.6, 95% CI: 1.93-16.42; p = 0.00036). Moreover, hypervariable MUC2 minisatellites were analyzed in matched blood and cancer tissue from 28 patients with gastric cancer and in 4 cases of MUC2-MS2, minisatellites were found to have undergone rearrangement. CONCLUSIONS/SIGNIFICANCE: Our observations suggest that the short rare MUC2-MS6 alleles could function as identifiers for risk of gastric cancer. Additionally, we suggest that minisatellite instability might be associated with MUC2 function in cancer cells
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