Abstract The spontaneous closure rate of patent ductus arteriosus (PDA) is high, and the necessity of early intervention is debated. Quantitative echocardiographic assessment of the intima in PDA has not been reported. This study evaluated intimal thickness growth in neonatal cases of PDA via echocardiography and investigated its correlation with clinical factors. Seventy-three neonates were enrolled, and echocardiography was performed three times: within 24 h post-birth (first echo), 48 h after the first echo (second echo), and before discharge (third echo). According to PDA outcome, the neonates were divided into the PDA-open group (n = 18 cases), PDA-closure at second echo group (n = 32 cases), and non-PDA at first echo group (n = 23 cases). We measured the intimal thickness (IT1 and IT2 at first and second echo, respectively), lumen diameter of ductus arteriosus (D1 and D2 at first and second echo, respectively), IT1/D1 ratio, and intimal thickness growth rate (V). Correlations between echocardiographic indicators, perinatal factors, and clinical treatment were analyzed. On first echo, the PDA-open group showed a significantly lower IT1/D1 than the combined PDA-closure group (P < 0.05). On second echo, the PDA-open group showed a significantly lower IT2 and V than the PDA-closure group as well as a significantly higher D2 (P < 0.05). Smaller gestational age correlated with a larger D2 but smaller IT2 and V (P < 0.05) and a higher level of respiratory support within 72 h post-birth correlated with a larger D2 and smaller IT 2 (P < 0.05). Increasing oxygen demand within 72 h of birth correlated with a larger D1 and D2 (P < 0.05). Echocardiographic assessment of intimal thickness growth in PDA may provide an approach for predicting spontaneous PDA closure, thereby guiding decision-making regarding early intervention.
The structure and function of β-glucan in barley have been reported to change significantly after fermentation with Lactobacillus plantarum dy-1, but little information is available to explain this phenomenon. The Carbohydrate-Active enZYmes database revealed that L. plantarum dy-1 encodes 158 types of glycosidic hydrolases, among which we have identified an endoglucanase. Therefore, we conducted a heterologous expression of this endoglucanase gene, namely Lpeg14265. The pH of 6.0 and the temperature of 60 °C were optimal for LPEG14265. The physiological activities of β-glucan, such as the capacity to adsorb cholesterol or to block α-amylase and α-glucosidase, increased as a result of enzymatic hydrolysis of LPEG14265, which also caused a significant change in the microstructure of barley bran. Based on these findings, it was concluded that barley bran, a by-product of agriculture, may be processed with LPEG14265 to reveal its potential value, which could have applications in the brewing and feed industries, among others.
The mean-field approximation method is proposed to investigate the intrinsic optical bistability in nonlinear composite media, which consists of nonlinear metallic granules embedded in nonlinear dielectric host. The effect of nonlinear susceptibility on the bistable behavior is analyzed. It is found that nonlinear metallic granules and nonlinear host medium have different effects and the nonlinearity of metallic granules is more effective in minimizing the threshould value of the bistable behavior. We also investigate the effect of the shape factor of metallic granules on the threshold value.
Hepatoid adenocarcinoma of the stomach (HAS) is a highly malignant subtype of gastric carcinoma with specific clinicopathological features and extremely poor prognosis. We present an exceedingly rare case of complete response after chemo-immunotherapy.A 48-year-old woman with highly elevated serum alpha-fetoprotein (AFP) level was found to have HAS verified by pathological examination based on gastroscopy. Computed tomography scan was done and TNM staging of the tumor was T4aN3aMx. Programmed cell death ligand-1 (PD-L1) immunohistochemistry was performed, revealing a negative PD-L1 expression. Chemo-immunotherapy including oxaliplatin plus S-1 and PD-1 inhibitor terelizumab was given to this patient for 2 months until the serum AFP level decreased from 748.5 to 12.9 ng/mL and the tumor shrank. D2 radical gastrectomy was then performed and histopathology of the resected specimen revealed that the cancerous cells had disappeared. Pathologic complete response (pCR) was achieved and no evidence of recurrence has been found after 1 year of follow-up.We, for the first time, reported an HAS patient with negative PD-L1 expression who achieved pCR from the combined chemotherapy and immunotherapy. Although no consensus has been reached regarding the therapy, it might provide a potential effective management strategy for HAS patient.
Wavelengths combination optimization in near infrared spectroscopy (NIRS) analysis was very important for improving model prediction effect, simplifying high dimension problems, reducing model complexity and designing special NIRS instruments with high signal noise ratio. Based on the prediction effect of single wavelength linear regression model, a special wavelength set with 25 information data points was filtered out. All wavelengths combinations of these 25 wavelengths were used to establish multiple linear regression (MLR) models respectively. With a prediction effect close to the PLS model based on whole spectral region, the simplest MLR model is the 7-wavelengths combination of 1105.5, 1108, 1895, 2150.5, 2278.5, 2284, 2286.5 (nm), RMSEP, R P , RRMSEP was 0.2505 (%), 0.8753, 15.73% respectively. This indicated that the wavelengths combination selection method based on the prediction effect of single wavelength linear regression model could be applied to the NIRS analysis and could provide valuable reference for designing minitype special NIRS instruments.
Accurate transfer RNA (tRNA) aminoacylation by aminoacyl-tRNA synthetases controls translational fidelity. Although tRNA synthetases are generally highly accurate, recent results show that the methionyl-tRNA synthetase (MetRS) is an exception. MetRS readily misacylates non-methionyl tRNAs at frequencies of up to 10% in mammalian cells; such mismethionylation may serve a beneficial role for cells to protect their own proteins against oxidative damage. The Escherichia coli MetRS mismethionylates two E. coli tRNA species in vitro, and these two tRNAs contain identity elements for mismethionylation. Here we investigate tRNA mismethionylation in Saccharomyces cerevisiae. tRNA mismethionylation occurs at a similar extent in vivo as in mammalian cells. Both cognate and mismethionylated tRNAs have similar turnover kinetics upon cycloheximide treatment. We identify specific arginine/lysine to methionine-substituted peptides in proteomic mass spectrometry, indicating that mismethionylated tRNAs are used in translation. The yeast MetRS is part of a complex containing the anchoring protein Arc1p and the glutamyl-tRNA synthetase (GluRS). The recombinant Arc1p-MetRS-GluRS complex binds and mismethionylates many tRNA species in vitro. Our results indicate that the yeast MetRS is responsible for extensive misacylation of non-methionyl tRNAs, and mismethionylation also occurs in this evolutionary branch.
A micromagnetic simulation is conducted to study the write field dynamics in the presence of antiferromagnetic exchange coupling (AFC) of writer pole for a perpendicular magnetic recording (PMR) writer head. It is found that, depending on the actual configuration of the AFC coupling in the yoke and the pole tip, there could be an intermediate transient state near zero write field during the magnetization reversal, compared to the normal writer design without AFC coupling. This transient state may cause recording performance degradation. We further investigated the AFC coupling effect on the remanent field in the degauss process. For different performance aspects, i.e., field dynamics, maximum field, and remanent field, the AFC in the yoke and in the pole tip plays different roles.
Based on a general beam-propagation model, we derive in the paraxial approximation the analytical expressions for the spatial transverse shift (TS) and the angular TS of a beam reflected from the air-chiral interface. The results show that the TSs are closely related to the propagation behaviors of the right-circularly polarized (RCP) and the left-circularly polarized (LCP) waves in the chiral medium. When the L(R)CP wave becomes evanescent, the left (right)-elliptically polarized incident beam suffers a smaller TS. When the L(R)CP wave propagates, the left (right)-elliptically polarized incident beam experiences a greater TS. When the total internal reflection happens, neither of the two elliptically polarized incident beams suffers TSs. TSs can be controlled not only by adjusting the central angle of incidence, but also by tailoring the permittivity, permeability, and chirality parameter of the chiral medium.