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The article reports on the human leukocyte antigen (HLA)-matching potential of a well known human embryonic stem cell bank in China. It indicates that the bank has 188 human embryonic stem cell (hESC) lines which came from an abnormal and poor-quality in vitro fertilization (IVF)-derived embryos. Moreover, it stresses that the bank can help in providing new hESC resources during stem cell research.

Background and Aims: Hepatic stellate cells (HSC) are known to synthesise excess matrix that characterises liver fibrosis and cirrhosis. Activated HSC express the matrix-degrading matrix metalloproteinase enzymes (MMPs) and their tissue inhibitors (TIMPs). During spontaneous recovery from experimental liver fibrosis, the expression of TIMP-1 declines and hepatic collagenolytic activity increases. This is accompanied by HSC apoptosis. In this study, we examine a potential mechanism whereby MMP activity might induce HSC apoptosis by cleaving N-cadherin at the cell surface. Results: N-cadherin expression was upregulated in human HSC during activation in culture. Addition of function-blocking antibodies or a peptide targeting the extracellular domain of N-cadherin, to cultured HSC, promoted apoptosis. During apoptosis, there was cleavage of N-cadherin into 20–100 kDa fragments. MMP-2 became activated early during HSC apoptosis and directly cleaved N-cadherin in vitro. Addition of activated MMP-2 to HSCs in culture resulted in enhanced apoptosis and loss of N-cadherin. Conclusions: Together, these studies identify a role for both N-cadherin and MMP-2 in mediating HSC apoptosis, where N-cadherin works to provide a cell survival stimulus and MMP-2 promotes HSC apoptosis concomitant with N-cadherin degradation. [ABSTRACT FROM AUTHOR]

Trichothecenes are isoprenoid mycotoxins produced in wheat infected with the filamentous fungus Fusarium graminearum. Some fungal genes for trichothecene biosynthesis ( Tri genes) are known to be under control of transcription factors encoded by Tri6 and Tri10. Tri6 and Tri10 deletion mutants were constructed in order to discover additional genes regulated by these factors in planta. Both mutants were greatly reduced in pathogenicity and toxin production and these phenotypes were largely restored by genetic complementation with the wild-type gene. Transcript levels for over 200 genes were altered ≥ twofold for Δtri6 or Δtri10 mutants including nearly all known Tri genes. Also reduced were transcript levels for enzymes in the isoprenoid biosynthetic pathway leading to farnesyl pyrophosphate, the immediate molecular precursor of trichothecenes. DNA sequences 5′ to isoprenoid biosynthetic genes were enriched for the Tri6p DNA binding motif, YNAGGCC, in F. graminearum but not in related species that do not produce trichothecenes. To determine the effect of trichothecene metabolites on gene expression, cultures were treated with trichodiene, the first metabolic intermediate specific to the trichothecene biosynthetic pathway. A total of 153 genes were upregulated by added trichodiene and were significantly enriched for genes likely involved in cellular transport. Differentially regulated genes will be targeted for functional analysis to discover additional factors involved in toxin biosynthesis, toxin resistance and pathogenesis. [ABSTRACT FROM AUTHOR]

Homozygous human embryonic stem cells (hESCs) are thought to be better cell sources for hESC banking because their human leukocyte antigen (HLA) haplotype would strongly increase the degree of matching for certain populations with relatively smaller cohorts of cell lines. Homozygous hESCs can be generated from parthenogenetic embryos, but only heterozygous hESCs have been established using the current strategy to artificially activate the oocyte without second polar body extrusion. Here we report the first successful derivation of a human homozygous ESC line (chHES-32) from a one-pronuclear oocyte following routine in vitro fertilization treatment. chHES-32 cells express common markers and genes with normal hESCs. They have been propagated in an undifferentiated state for more than a year (>P50) and have maintained a stable karyotype of 46, XX. When differentiated in vivo and in vitro, chHES-32 cells can form derivatives from all three embryonic germ layers. The almost undetectable expression of five paternally expressed imprinted genes and their HLA genotype identical to the oocyte donor indicated their parthenogenetic origin. Using genome-wide single-nucleotide polymorphism analysis and DNA fingerprinting, the homozygosity of chHES-32 cells was further confirmed. The results indicated that 'unwanted' one-pronuclear oocytes might be a potential source for human homozygous and parthenogenetic ESCs, and suggested an alternative strategy for obtaining homozygous hESC lines from parthenogenetic haploid oocytes.Cell Research (2007) 17: 999–1007. doi: 10.1038/cr.2007.97; published online 27 November 2007 [ABSTRACT FROM AUTHOR]

Cyanide or metal cyanide contaminations have become serious environmental and food-health problems. A fungal mutant of Trichoderma koningii, TkA8, constructed by restriction enzyme-mediated integration, has been verified to have a high cyanide degradation ability in our previous study. In this study, the mutant cells were entrapped in sodium-alginate (Na-alginate) immobilization beads to degrade cyanide and ferrocyanide in a liquid mineral medium. The results showed that the fungus in immobilization beads consisting of 3% Na-alginate and 3% CaCl2 could degrade cyanide more efficiently than a nonimmobilized fungal culture. For maximum degradation efficiency, the optimal ratio of Na-alginate and wet fungal biomass was 20:1 (m/m) and the initial pH was 6.5. In comparison, cell immobilization took at least 3 and 8 days earlier, respectively, to completely degrade cyanide and ferrocyanide. In addition, we showed that the immobilized beads could be easily recovered from the medium and reused for up to 5 batches without significant losses of fungal remediation abilities. The results of this study provide a promising alternative method for the large-scale remediation of soil or water systems from cyanide contamination. [ABSTRACT FROM AUTHOR]

We study the influence of electrodes on the exponential transport rule for the junction of oligophenylene-linked and oligoacene-linked molecules between two zigzag phosphorene nanoribbons (ZPNRs), where molecules consisting of one, two and three benzene rings are considered, respectively. We find by ab initio calculations that the amplitude of current through the junction is dependent on both the molecular length and the molecule–ZPNR coupling manner. In specification, the current through the single-bond coupled junction with the molecular plane perpendicular to the ZPNRs is almost two times that with parallel configuration due to the greater number of transport channels provided by the p y  orbital in the former case. In contrast, the current of the junction with double-bond coupling is nearly two orders of magnitude larger because of the stronger coupling strength. Nevertheless, in any case the ZPNR–electrode junction, like metal–electrode junctions, also obeys the exponential decaying rule in transport with the variation of molecular length. Importantly, the relationship between the resistance and the molecular length, regardless of the coupling details, can be fitted by a linear line in the semilog coordinate but with different slopes determined by the coupling manner. This indicates that the exponential rule of transport under small bias voltages is electrode-material-independent for molecular junctions with any electrode. But the value of the decaying factor, importantly, is heavily dependent not only on the molecule itself but also on the electrode materials as well as the molecule–electrode coupling method. [ABSTRACT FROM AUTHOR]

In this paper， one 180 t double-hole bottom argon blowing ladle is taken as the research object. Based on the specific production conditions， six modes of argon bottom blowing in ladle are numerically simulated， and combined with the field test， it is compared with the argon blowing mode currently adopted. The results show that： （1） The mixing time of molten steel decreases with the increase of argon blowing amount. When argon blowing amount is constant， the argon blowing mode with differential flow rate is stronger than that with constant flow rate. （2） Different modes of argon blowing at the bottom of ladle have different locations and areas of slag holes. When the total flow rate is constant， the maximum velocity of molten steel surface in the differential flow argon blowing mode is greater than that in the constant flow argon blowing mode， which is easy to cause slag entrapment. （3） The fluctuation of slag layer thickness at the slag line in differential flow argon blowing mode is greater than that in constant flow argon blowing mode， and the greater the flow difference， the more severe the fluctuation. （4） The differential flow argon blowing mode further strengthens the refining effect of molten steel by argon blowing at the bottom of ladle through the cooperation of "strong-weak" streams. And the industrial test shows that the number of larger inclusions in steel is obviously more than that in argon blowing mode （400 L/min-600 L/min） with constant flow rate （500 L/min-500 L/min）.

BACKGROUND: We aimed to analyze the independent risk factors that affect the treatment outcomes of residual symptoms of cured benign paroxysmal positional vertigoand to construct a nomogram model. METHODS: A total of 186 benign paroxysmal positional vertigo patients who were treated in our hospital from June 2019 to August 2021 were selected. According to whether there were residual symptoms, they were divided into a group with residual symptoms (n = 82) and a group without residual symptoms (n = 104). The logistic regression model was used to analyze the independent risk factors affecting the treatment outcomes, and the results were incorporated into R software to establish a nomogram model for verification. RESULTS: The incidence rate of residual symptoms in the 186 patients was 44.09% (82/186). Logistic regression analysis showed that age, course of disease, number of maneuvers, anxiety state, diabetes mellitus, and hypertension were independent risk factors affecting the treatment outcomes of residual symptoms after cured benign paroxysmal positional vertigo. The area under the receiver operating characteristic curve of the nomogram model was 0.938. The calibration curve was fitted well (χ² = 8.165, P = .417). CONCLUSION: The nomogram model constructed based on age, course of disease, number of maneuvers, anxiety state, diabetes mellitus, and hypertension had a high predictive value for the treatment outcomes of residual symptoms in benign paroxysmal positional vertigo patients. [ABSTRACT FROM AUTHOR]

We investigate theoretically the electronic properties of two-dimensional electron gases (2DEGs) with regular and distorted triangular antidot lattices. We show that the triangular antidot lattices embedded in 2DEGs behave like artificial graphene and host Dirac fermions. By introducing the Wannier representation, we obtain a tight-binding Hamiltonian including the second-nearest-neighboring hopping, which agrees well with the numerically exact solutions. Based on the tight-binding model, we find that spatially nonuniform distortions of the antidot lattices strongly modify the electronic structures, generate pseudomagnetic fields and the well-defined Landau levels. In contrast to graphene, we can design the nonuniform distortions to generate various configurations of pseudomagnetic fields. We show that the snake orbital states arise by designing the ±B pseudomagnetic field configuration. We find that the disorders of antidot lattices during fabrication would not affect the basic feature of the Dirac electrons, but they lead to a reduction in conductance in strong disorder cases. [ABSTRACT FROM AUTHOR]

We study the variation of electronic property for zigzag-edge phosphorene nanoribbons (ZPNRs) under a perpendicular electric field (PEF). Using the tight-binding Hamiltonian combined with the surface lattice Green’s function (GF) approach, we show that the response of edge states to PEF for a N-ZPNR with even- or odd-N (number of zigzag chains) is qualitatively different. The field opens a gap between two edge bands near the Fermi energy for even-N ribbons, but for odd-N ones where the two edge bands are always nearly degenerated. This difference is originally from that the Stark-effect-induced energies at the upper and lower edges for even- and odd-N ZPNRs are different due to the peculiar lattice structure of phosphorene. In consequence, the electronic densities are more localized at the edges driven by the field for even-N ZPNRs but not for odd-N ones. This even–odd effect is also reflected in conductance, which indicates that the odd-N ZPNRs may be more suitable for the usage of field-effect transistor. [ABSTRACT FROM AUTHOR]

We theoretically investigate the effective g factor in the black phosphorus (BP) thin films (TFs) based on a multiband k.p theory. We demonstrate that the effective single particle g factor in pristine BP TF is anisotropic arising from its anisotropic band structure with g*xx≈g*yy ≈ 2.0 and g*zz sensitively depending on the interband coupling and the band gap. The g*zz approaches 2.0 with increasing hole doping density and gate electric field since both of them minish the interband coupling by reducing the overlap integral between the electron and hole wave functions. We also estimate the exchange interaction enhancement on the effective single particle g factor by using the screened Hartree-Fock approximation. The exchange interaction enhanced g factor (gex) shows maxima (minima) at odd (even) filling factors. The effective g factor (g*) oscillates with the increase of magnetic field and sensitively depends on the Landau level broadening as well as the gate electric field since both of them affect the interband coupling and the electron-electron interactions. [ABSTRACT FROM AUTHOR]

We theoretically investigate the Landau levels (LLs) and magneto-optical conductivity (MOC) of black phosphorus thin films under a perpendicular magnetic field based on an effective k·p Hamiltonian and linear-response theory. We obtain the analytical expression for LLs, which agrees well with the numerical calculations, and find that the LLs sublinearly depend on the magnetic field and LL index. By using the Kubo formula, we evaluate the longitudinal and Hall optical conductivities as functions of the photon energy and the magnetic field. The analytical optical transition matrix elements reveal unusual selection rules for the interband (intraband) optical transitions between the LLs Δn=0,±2 (±1,±3). The MOC shows strongly anisotropic behaviors of the band structure. For the interband transition, the MOC for linearly polarized light along the armchair direction is three orders of magnitude larger than that along the zigzag direction. Interestingly, we find a beating pattern in the interband MOC due to the interference among the three kinds of optical transitions. For the intraband transition, the MOC can be used to determine the band parameters such as the effective masses and the interband coupling at zero magnetic field. Our results about the MOC can also be applied to the monolayer black phosphorus. [ABSTRACT FROM AUTHOR]

Ultrasound nanodroplets (NDs) have been reported as a promising nanocarrier for siRNA delivery depending on its unique strengths of sonoporation. Presently, common means for NDs-mediated siRNA delivery is through electrostatic interaction, but challenges like cationic toxicity still exist. In this study, we demonstrated a novel strategy to construct negatively charged and ultrasound (US)-responsive O-carboxymethyl chitosan (O-CMS) NDs as a siRNA targeted delivery system through three-way junction of bacteriophage phi29 DNA packaging motor (3WJ-pRNA) nanotechnology. 39nt A10-3.2 aptamer targeting prostate specific membrane antigen (PSMA) and 21nt siRNA against cationic amino acid transporter 1 (siCAT-1) were annealed to 3WJ-pRNA scaffold via complementation with an extended sequence. The cholesterol molecule attached to one branch facilitates the 3WJ-pRNA nanoparticles anchoring onto NDs. The desired O-CMS NDs with siRNA-loading and RNA-aptamer modification (A10-3.2/siCAT-1/3WJ-NDs) were successfully prepared, which were with spherical shapes, core-shell structures and uniform in sizes (198nm with PDI 0.3). As a main proportion of shell, O-CMC showed a certain anti-tumor effects. In vitro studies demonstrated that A10-3.2/siCAT-1/3WJ-NDs exhibited good contrast-enhanced US imaging, buffering capacity and high bio-safety, were able to deliver siCAT-1 to PSMA-overexpressed prostate cancer cells under US irradiation, thus silence the CAT-1 expression, and consequently suppressing 22RV1 cell proliferation and migration. Taken overall, our findings provide a promising strategy to develop negatively charged and US-responsive NDs for tumor-targeted siRNA delivery. [ABSTRACT FROM AUTHOR]

The construction of multifunctional oncotherapy nanoplatforms that combine diagnosis and treatment remains challenging. Nanodroplets (NDs), which simultaneously enhance ultrasound imaging and therapeutic effects, are a potential strategy for non-invasive drug delivery. To achieve the goals of precise medicine, novel SP94 peptide-modified and doxorubicin-loaded ultrasonic NDs (SP94-DOX-NDs) for castration-resistant prostate cancer (CRPC) targeting and treatment were constructed in this study. The characteristics, contrast-enhanced ultrasound imaging (CEUI), targeting ability to glucose-regulated protein 78 (GRP78)-overexpressing CRPC and anticancer effect of the SP94-DOX-NDs were assessed. The desired SP94-NDs were successfully prepared using the nanoemulsification method using a certain proportion of SP94-PEG-chitosan, perfluoropentane (PFP), Tween 20, and lecithin. SP94-NDs with a size of -300nm showed great biocompatibility and CEUI ability. Compared with blank NDs, SP94-NDs exhibited higher tumor-specific targeting ability due to conjugation between the SP94 peptide and GRP78-overexpressing 22RV1 cells. Most importantly, in vitro and in vivo investigations showed that SP94-DOX-NDs combined with ultrasound could specifically deliver DOX into 22RV1 cells and thereby demonstrated a stronger anticancer effect than DOX-NDs and DOX. Thus, SP94-DOX-NDs may provide an efficient approach for the real-time imaging of tumors and triggered, accurate drug delivery to tumors. [ABSTRACT FROM AUTHOR]

BACKGROUNDThere has been a striking generational increase in the prevalence of food allergies. We have proposed that this increase can be explained, in part, by alterations in the commensal microbiome.METHODSTo identify bacterial signatures and metabolic pathways that may influence the expression of this disease, we collected fecal samples from a unique, well-controlled cohort of twins concordant or discordant for food allergy. Samples were analyzed by integrating 16S rRNA gene amplicon sequencing and liquid chromatography-tandem mass spectrometry metabolite profiling.RESULTSA bacterial signature of 64 operational taxonomic units (OTUs) distinguished healthy from allergic twins; the OTUs enriched in the healthy twins were largely taxa from the Clostridia class. We detected significant enrichment in distinct metabolite pathways in each group. The enrichment of diacylglycerol in healthy twins is of particular interest for its potential as a readily measurable fecal biomarker of health. In addition, an integrated microbial-metabolomic analysis identified a significant association between healthy twins and Phascolarctobacterium faecium and Ruminococcus bromii, suggesting new possibilities for the development of live microbiome-modulating biotherapeutics.CONCLUSIONTwin pairs exhibited significant differences in their fecal microbiomes and metabolomes through adulthood, suggesting that the gut microbiota may play a protective role in patients with food allergies beyond the infant stage.TRIAL REGISTRATIONParticipants in this study were recruited as part of an observational study (ClinicalTrials.gov NCT01613885) at multiple sites from 2014 to 2018.FUNDINGThis work was supported by the Sunshine Charitable Foundation; the Moss Family Foundation; the National Institute of Allergy and Infectious Diseases (NIAID) (R56AI134923 and R01AI 140134); the Sean N. Parker Center for Allergy and Asthma Research; the National Heart, Lung, and Blood Institute (R01 HL 118612); the Orsak family; the Kepner family; and the Stanford Institute for Immunity, Transplant and Infection. [ABSTRACT FROM AUTHOR]

A fiber sphere-embedded long-period fiber grating (LPFG) sensor has been proposed and fabricated for curvature measurement with high sensitivity. Compared with the normal LPFG, the embedded fiber sphere excites cladding modes and two dips of the output spectrum have been observed. The curvature measurement can be realized by monitoring the shift of the two dips. Experimental results show that the highest curvature sensitivity is up to -104.642 nm/m-1 with the curvature ranging from 0 to 0.71 m-1. The temperature response of the sensor has also been studied and a quadratic linear relationship between the dip shift and the temperature has been observed. The highest temperature sensitivity is 0.36 nm/°C with the temperature range between 20°C and 90°C. [ABSTRACT FROM AUTHOR]

Background: Subjects with elevated Epstein-Barr virus (EBV) immunoglobulin A (IgA) titers have a higher risk of developing nasopharyngeal carcinoma (NPC), indicating that reactivation of EBV in the local mucosa might be important for NPC carcinogenesis. Cigarette smoking appears to be one of the environmental risk factors for NPC. However, it remains unclear whether smoking-induced nasopharyngeal carcinogenesis acts through reactivating EBV in the nasopharyngeal mucosa. Therefore, this study aims to investigate the association between cigarette smoking and nasopharyngeal EBV reactivation in a NPC high-risk population.Methods: A NPC high-risk cohort study, established from a population-based NPC screening program of 22,816 subjects, consisted of 1045 subjects with elevated serum IgA antibodies against EBV viral capsid antigen (VCA/IgA). Among high-risk subjects, information on detailed cigarette smoking history was collected among 313 male subjects. The associations between cigarette smoking and EBV antibody levels, EBV DNA load of the nasopharynx were analyzed.Results: No significant association was observed between either nasopharyngeal EBV DNA load or serum VCA/IgA titers and smoking status, age at smoking initiation, daily smoking intensity, smoking duration, cigarette type, or pack-years of smoking. Cigarette smoking characteristics in all subgroups did not correlate with nasopharyngeal EBV DNA positivity or EBV VCA/IgA seropositivity.Conclusions: In a population at high risk of NPC, our study suggests that cigarette smoking is neither associated with nasopharyngeal EBV DNA load nor serum VCA/IgA antibody level. Smoking-associated NPC carcinogenesis may act through other mechanisms than reactivating nasopharyngeal EBV replication. [ABSTRACT FROM AUTHOR]

Dipeptidyl peptidase I (DPPI) is a lysosomal cysteine protease and derived from immune granule cells. It has been suggested playing an important role in the development of rheumatoid arthritis. In this study, a coumarin based fluorescent probe (GF-AFC) was designed and synthesized to evaluate DPPI activity in serum or tissue homogenates of collagen-induced arthritis (CIA) rats, an inflammatory arthropathy model. It was revealed that the fluorescent intensity was significantly increased in a very short time after specific substrate GF-AFC reacted with the DPPI. The fluorophore (AFC) was released to shine after the cleavage reaction which was examined by 19F NMR spectroscopy. It has been shown that DPPI hydrolyzed the GF-AFC in a robust, linear, and time dependent manner at a significant high rate. A serum-based DPPI activity assay was validated by spiking and gradient dilution methods, there were no interferences or auto-fluorescence observed. The Coefficient of Variance calculated for serum-based DPPI activity assays indicates the good reproducibility. The good correlation has been seen between serum DPPI levels and the severity of arthritis during RA development in CIA rats. Our study has demonstrated a new serum based diagnostic assay for detecting DPPI activity using coumarin conjugated fluorescent (GF-AFC) as a substrate. The successful implementation of the case would provide beneficial experience in rheumatoid arthritis research. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effectiveness of pedicled superior gluteal artery perforator bilateral quadrilobed flaps for repairing large sacrococcygeal pressure sores., Methods: Between June 2003 and August 2011, 6 paraplegia patients with large sacrococcygeal pressure sores were repaired with the pedicled superior gluteal artery perforator bilateral quadrilobed flaps. There were 2 males and 4 females with an average age of 45.6 years (range, 37-62 years). The mean disease duration was 8.4 months (range, 3-26 months). According to National Pressure Ulcer Advisory Panel (NPUAP) standard, 6 cases rated as degree IV. The size of pressure sores ranged from 15 cm x 13 cm to 18 cm x 16 cm. The size of flaps ranged from 18 cm x 14 cm to 21 cm x 15 cm., Results: After operation, all flaps survived successfully. The wounds healed by first intention in 5 cases; partial dehiscence of incision occurred in 1 case, which was cured after dressing change for 26 days. Six patients were followed up 6-24 months (mean, 12.5 months). The appearance and texture of the flaps were smooth and soft with good elasticity and no ulceration., Conclusion: Pedicled superior gluteal artery perforator bilateral quadrilobed flaps can repair large sacrococcygeal pressure sores. The appearance of flaps is smooth and has good compression-resistance effect.