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We investigated the prognostic importance of noninvasive factors in predicting sperm retrieval failure in idiopathic nonobstructive azoospermia (iNOA). We studied 193 patients with nonobstructive azoospermia who underwent microsurgical testicular sperm extraction. The Chi-square test and Mann–Whitney U tests for clinical parameters and seminiferous tubule distribution were used for between-group comparisons. A logistic regression analysis was conducted to identify predictors of retrieval failure. Area under the receiver operating characteristic curve for each variable was evaluated, and the net clinical benefit was calculated using a clinical decision curve. Patients with iNOA had a lower sperm retrieval rate than those with known causes. Moreover, testicular volume was an independent factor affecting sperm extraction outcomes (odds ratio = 0.79, P < 0.05). The testicular volume cut-off value was 6.5 ml (area under the curve: 0.694). The patients with iNOA were categorized into two groups on the basis of the distribution of seminiferous tubules observed. The sperm retrieval rate and testicular volume were significantly different between the groups with a uniform or heterogeneous tubule distribution. There was also a significant association between a uniform tubule distribution and testicular volume. In conclusion, a testicular volume of more than 6.5 ml effectively predicts microsurgical testicular sperm extraction failure due to a uniform tubule distribution in patients with iNOA. [ABSTRACT FROM AUTHOR]

Two-dimensional electron gases (2DEGs) formed at the interface between two oxide insulators present a promising platform for the exploration of emergent phenomena. While most of the previous works focused on SrTiO3-based 2DEGs, here we took the amorphous-ABO3/KTaO3 system as the research object to study the relationship between the interface conductivity and the redox property of B-site metal in the amorphous film. The criterion of oxide–oxide interface redox reactions for the B-site metals, Zr, Al, Ti, Ta, and Nb in conductive interfaces was revealed: the formation heat of metal oxide, , is lower than –350 kJ/(mol O) and the work function of the metal Φ is in the range of 3.75 eV < Φ < 4.4 eV. Furthermore, we found that the smaller absolute value of and the larger value of Φ of the B-site metal would result in higher mobility of the two-dimensional electron gas that formed at the corresponding amorphous-ABO3/KTaO3 interface. This finding paves the way for the design of high-mobility all-oxide electronic devices. [ABSTRACT FROM AUTHOR]

The electric gating on the transport properties of two-dimensional electron gas (2DEG) at the interface of LaAlO3/SrTiO3 (LAO/STO) heterostructure has attracted great research interest due to its potential application in field-effect devices. Most of previous works of gate effect were focused on the LAO/STO heterostructure containing only one conductive interface. Here, we systematically investigated the gate effect on high-quality LAO/STO superlattices (SLs) fabricated on the TiO2-terminated (001) STO substrates. In addition to the good metallicity of all SLs, we found that there are two types of charge carriers, the majority carriers and the minority carriers, coexisting in the SLs. The sheet resistance of the SLs with a fixed thickness of the LAO layer increases monotonically as the thickness of the STO layer increases. This is derived from the dependence of the minority carrier density on the thickness of STO. Unlike the LAO/STO heterostructure in which minority and majority carriers are simultaneously modulated by the gate effect, the minority carriers in the SLs can be tuned more significantly by the electric gating while the density of majority carriers is almost invariable. Thus, we consider that the minority carriers may mainly exist in the first interface near the STO substrate that is more sensitive to the back-gate voltage, and the majority carriers exist in the post-deposited STO layers. The SL structure provides the space separation for the multichannel conduction in the 2DEG, which opens an avenue for the design of field-effect devices based on LAO/STO heterostructure. [ABSTRACT FROM AUTHOR]

Grouping different oxide materials with coupled charge, spin, and orbital degrees of freedom together to form heterostructures provides a rich playground to explore the emergent interfacial phenomena. The perovskite/brownmillerite heterostructure is particularly interesting since symmetry mismatch may produce considerable interface reconstruction and unexpected physical effects. Here, we systemically study the magnetic anisotropy of tensely strained La2/3Sr1/3Co1 – xMnxO2.5 + δ/La2/3Sr1/3MnO3/La2/3Sr1/3Co1 – xMnxO2.5 + δ trilayers with interface structures changing from perovskite/brownmillerite type to perovskite/perovskite type. Without Mn doping, the initial La2/3Sr1/3CoO2.5 + δ/La2/3Sr1/3MnO3/La2/3Sr1/3CoO2.5 + δ trilayer with perovskite/brownmillerite interface type exhibits perpendicular magnetic anisotropy and the maximal anisotropy constant is 3.385 × 106 erg/cm3, which is more than one orders of magnitude larger than that of same strained LSMO film. By increasing the Mn doping concentration, the anisotropy constant displays monotonic reduction and even changes from perpendicular magnetic anisotropy to in-plane magnetic anisotropy, which is possible because of the reduced CoO4 tetrahedra concentration in the La2/3Sr1/3Co1 – xMnxO2.5 + δ layers near the interface. Based on the analysis of the x-ray linear dichroism, the orbital reconstruction of Mn ions occurs at the interface of the trilayers and thus results in the controllable magnetic anisotropy. [ABSTRACT FROM AUTHOR]

An oxide p–n heterojunction composed of a 150-nm La0.67Ca0.33MnO3 (LCMO) film, 0.05 wt% Nb doped SrTiO3 substrate (STON), and sandwiched 5-nm LaAlO3 (LAO) thin film is fabricated with the pulsed laser deposition technique and the interfacial transport properties are experimentally studied. The rectifying behavior of the junction is in agreement with Newman’s equation, indicating that tunneling is the dominant process for the carriers to pass through the interface while thermal emission is the dominant transport model of an LCMO/STON heterojunction with no LAO buffer layer. [ABSTRACT FROM AUTHOR]

Abstract: Although microsurgical vasoepididymostomy (MVE) is an effective treatment for epididymal obstructive azoospermia, some patients may experience delayed patency or suboptimal semen parameters after patency. However, research into patency time, semen quality postpatency, and associated influencing factors remains limited. This study aimed to address these issues by evaluating 181 patients who underwent at least one-sided MVE employing asingle-armed longitudinal intussusception vasoepididymostomy technique, with a follow-up period of over 12 months for 150 patients. The overall patency rate was 75.3%, with 86.0% of patients achieving patency within 6 months following MVE. Unexpectedly, factors such as age, history of epididymitis, duration of surgery, side of anastomosis, sperm motility in epididymal fluid, and the site of anastomosis showed no correlation with patency time. Nonetheless, our univariate and multivariate linear regression analysis indicated that only the site of anastomosis was positively correlated with and could independently predict postoperative total motile sperm count. Therefore, the site of anastomosis might serve as a predictor for optimal postoperative semen quality following the MVE procedure., (Copyright © 2024 Copyright: ©The Author(s)(2024).)

Abstract: The cause of asthenozoospermia (AZS) is not well understood because of its complexity and heterogeneity. Although some gene mutations have been identified as contributing factors, they are only responsible for a small number of cases. Radial spokes (RSs) are critical for adenosine triphosphate-driven flagellar beating and axoneme stability, which is essential for flagellum motility. In this study, we found novel compound heterozygous mutations in leucine-rich repeat-containing protein 23 ( LRRC23 ; c.1018C>T: p.Q340X and c.881&#95;897 Del: p.R295Gfs*32) in a proband from a nonconsanguineous family with AZS and male infertility. Diff-Quik staining and scanning electron microscopy revealed no abnormal sperm morphology. Western blotting and immunofluorescence staining showed that these mutations suppressed LRRC23 expression in sperm flagella. Additionally, transmission electron microscopy showed the absence of RS3 in sperm flagella, which disrupts stability of the radial spoke complex and impairs motility. Following in vitro fertilization and embryo transfer, the proband's spouse achieved successful pregnancy and delivered a healthy baby. In conclusion, our study indicates that two novel mutations in LRRC23 are associated with AZS, but successful fertility outcomes can be achieved by in vitro fertilization-embryo transfer techniques., (Copyright © 2024 Copyright: ©The Author(s)(2024).)

Objective: To determine the frequency distribution and antibiotic resistance of pathogens isolated from the cerebrospinal fluid samples of children with bacterial meningitis (BM) and to provide a basis for the timely and effective treatment of childhood BM., Methods: Retrospective analysis was performed on pathogens isolated from 5097 cerebrospinal fluid samples collected from children in Kunming Children's Hospital between January 2008 and June 2012, as well as drug sensitivity test results. Kirby-Bauer antibiotic testing was used to analyze the sensitivity of these pathogens to commonly used antibiotics., Results: A total of 116 pathogen strains were detected from the 5097 cerebrospinal fluid samples, including 77 (66.4%) Gram-positive strains, 30 (25.9%) Gram-negative strains, and 9 (7.8%) fungal strains, with a positive rate of 2.28%. The six most frequently isolated pathogens were Staphylococcus epidermidis (32 strains, 27.6%), Streptococcus pneumoniae (15 strains, 12.9%), Escherichia coli (15 strains, 12.9%), Staphylococcus haemolyticus (9 strains, 7.8%), Cryptococcus neoformans (8 strains, 6.9%) and Staphylococcus aureus (6 strains, 5.2%). Coagulase-negative staphylococci was the predominant pathogen in neonates and young infants with BM, and its sensitivity rates to penicillin, erythromycin and clindamycin were lower than 40%. Streptococcus pneumoniae had a penicillin sensitivity rate of 13.4%, while sensitivity rates to erythromycin and clindamycin reached 60.0%. No Staphylococcus and Streptococcus pneumoniae pathogens resistant to vancomycin were found. Gram-negative bacilli had relatively high sensitivity rates to imipenem, meropenem, cefoperazone/sulbactam and cefepime., Conclusions: Gram-positive cocci are the predominant pathogens for childhood BM over the past five years. The detected pathogens develop high resistance to commonly used antibiotics. To prevent misdiagnosis, careful attention should be paid to BM caused by Cryptococcus neoformans.