Divergent Synthesis and Antigenicity Evaluation of Core Oligosaccharides of the Lipopolysaccharides from Acinetobacter baumannii SMAL and ATCC 19606.

Acinetobacter baumannii poses a serious threat to human health. Pathogenic bacterial lipopolysaccharides (LPSs) are potent immunogens for the development of antibacterial vaccines. To investigate the antigenic properties of A. baumannii LPS, five well-defined core oligosaccharide fragments from the LPS of A. baumannii SMAL and ATCC 19606 were synthesized. A divergent synthesis strategy based on orthogonally protected α-(2 → 5)-linked Kdo dimer 6 was developed. Selective exposure of different positions in this key precursor and then elongation of sugar chains via stereocontrolled formation of both 1,2-trans and 1,2-cis-2-aminoglycosidic linkages permitted the efficient synthesis of the targets. The synthetic route also highlights a 4-O and then 7-O glycosylation sequence for assembly of the novel 4,7-branched Kdo framework. Antigenicity assay using the glycan microarray technique disclosed that tetrasaccharide 3 featuring both 4,7-branch and α-(2 → 5)-Kdo-Kdo structural elements was a potential antigenic determinant.

Enhancing homology-directed repair efficiency with HDR-boosting modular ssDNA donor.

Despite the potential of small molecules and recombinant proteins to enhance the efficiency of homology-directed repair (HDR), single-stranded DNA (ssDNA) donors, as currently designed and chemically modified, remain suboptimal for precise gene editing. Here, we screen the biased ssDNA binding sequences of DNA repair-related proteins and engineer RAD51-preferred sequences into HDR-boosting modules for ssDNA donors. Donors with these modules exhibit an augmented affinity for RAD51, thereby enhancing HDR efficiency across various genomic loci and cell types when cooperated with Cas9, nCas9, and Cas12a. By combining with an inhibitor of non-homologous end joining (NHEJ) or the HDRobust strategy, these modular ssDNA donors achieve up to 90.03% (median 74.81%) HDR efficiency. The HDR-boosting modules targeting an endogenous protein enable a chemical modification-free strategy to improve the efficacy of ssDNA donors for precise gene editing.

A randomized, double-blind, placebo-controlled phase I clinical trial of rotavirus inactivated vaccine (Vero cell) in a healthy adult population aged 18-49 years to assess safety and preliminary observation of immunogenicity.

We conducted a phase I, randomized, double-blind, placebo-controlled trial including healthy adults in Sui County, Henan Province, China. Ninety-six adults were randomly assigned to one of three groups (high-dose, medium-dose, and low-dose) at a 3:1 ratio to receive one vaccine dose or placebo. Adverse events up to 28 days after each dose and serious adverse events up to 6 months after all doses were reported. Geometric mean titers and seroconversion rates were measured for anti-rotavirus neutralizing antibodies using microneutralization tests. The rates of total adverse events in the placebo group, low-dose group, medium-dose group, and high-dose group were 29.17 % (12.62 %-51.09 %), 12.50 % (2.66 %-32.36 %), 50.00 % (29.12 %-70.88 %), and 41.67 % (22.11 %-63.36 %), respectively, with no significant difference in the experimental groups compared with the placebo group. The results of the neutralizing antibody assay showed that in the adult group, the neutralizing antibody geometric mean titer at 28 days after full immunization in the low-dose group was 583.01 (95 % confidence interval [CI]: 447.12-760.20), that in the medium-dose group was 899.34 (95 % CI: 601.73-1344.14), and that in the high-dose group was 1055.24 (95 % CI: 876.28-1270.75). The GMT of serum-specific IgG at 28 days after full immunization in the low-dose group was 3444.26 (95 % CI: 2292.35-5175.02), that in the medium-dose group was 6888.55 (95 % CI: 4426.67-10719.6), and that in the high-dose group was 7511.99 (95 % CI: 3988.27-14149.0). The GMT of serum-specific IgA at 28 days after full immunization in the low-dose group was 2332.14 (95 % CI: 1538.82-3534.45), that in the medium-dose group was 4800.98 (95 % CI: 2986.64-7717.50), and that in the high-dose group was 3204.30 (95 % CI: 2175.66-4719.27). In terms of safety, adverse events were mainly Grades 1 and 2, indicating that the safety of the vaccine is within the acceptable range in the healthy adult population. Considering the GMT and positive transfer rate of neutralizing antibodies for the main immunogenicity endpoints in the experimental groups, it was initially observed that the high-dose group had higher levels of neutralizing antibodies than the medium- and low-dose groups in adults aged 18-49 years. This novel inactivated rotavirus vaccine was generally well-tolerated in adults, and the vaccine was immunogenic in adults (ClinicalTrials.gov number, NCT04626856).

The applied principles of EEG analysis methods in neuroscience and clinical neurology.

Electroencephalography (EEG) is a non-invasive measurement method for brain activity. Due to its safety, high resolution, and hypersensitivity to dynamic changes in brain neural signals, EEG has aroused much interest in scientific research and medical fields. This article reviews the types of EEG signals, multiple EEG signal analysis methods, and the application of relevant methods in the neuroscience field and for diagnosing neurological diseases. First, three types of EEG signals, including time-invariant EEG, accurate event-related EEG, and random event-related EEG, are introduced. Second, five main directions for the methods of EEG analysis, including power spectrum analysis, time-frequency analysis, connectivity analysis, source localization methods, and machine learning methods, are described in the main section, along with different sub-methods and effect evaluations for solving the same problem. Finally, the application scenarios of different EEG analysis methods are emphasized, and the advantages and disadvantages of similar methods are distinguished. This article is expected to assist researchers in selecting suitable EEG analysis methods based on their research objectives, provide references for subsequent research, and summarize current issues and prospects for the future.

Association between time from anterior cruciate ligament injury to reconstruction and morphological changes of the intercondylar notch using MRI and arthroscopy.

BACKGROUND: Few studies have measured the dimensions of intercondylar notch under direct arthroscopic visualization. The purpose of our study was to analyse the association between time from anterior cruciate ligament (ACL) injury to reconstruction and the morphological changes of intercondylar notch using magnetic resonance imaging (MRI) and arthroscopy. METHODS: Data was collected for patients who received knee arthroscopic surgery during 2014-2015. According to the time from ACL injury to reconstruction, these patients were divided into five groupsACL non-injured group (NI), acute rupture group (AR, <3 months), chronic rupture group 1 (CR1, 3-12 months), 2 (CR2, 1-5 years) and 3 (CR3, >5 years). MRI measurements of femoral condylar width (FCW) and intercondylar width (ICW) were undertaken before surgery. The widths at the base, middle and top of the intercondylar notch (ICWb, ICWm, ICWt, respectively) and the intercondylar notch height (ICH) were measured during arthroscopy. Intercondylar notch width index (NWI) and notch shape index (NSI) were then calculated and analysed among groups. RESULTS: A total of 272 patients were allocated to groups NI (n = 89), AR (n = 84), CR1 (n = 51), CR2 (n = 30) or CR3 (n = 18). Statistical analysis showed significant differences in ICW, ICWb, ICH, NWI and NSI between groups NI and AR. Among the groups with ACL-injury, ICWb and ICWt and NWI in group CR3 were statistically smaller than the other three groups (P = 0.004, 0.016, and 0.005, respectively). CONCLUSIONS: The width of intercondylar notch had a negative correlation with time from ACL injury to reconstruction. Significant secondary notch stenosis was observed over 5 years after ACL rupture.

A systematic review of clinical efficacy of frozen-thawed embryos and fresh embryos in in-vitro fertilization cycles.

BACKGROUND: Frozen-thawed embryo (FTE) and fresh embryo (FE) transfer are two common strategies in vitro fertilization (IVF), while the results and findings still vary among studies. METHODS: We searched multiple databases for relevant studies comparing the clinical effects of FTE and FE. Meta-analyses were conducted with Review Manager 5.0 to assess the efficacy among included articles. We also analyzed the risk of bias for the reports. RESULTS: Nine studies eventually met the inclusion criteria from 2010 to 2018, and 11396 patients were included. The meta-analyses indicated no significant difference in biochemical pregnancy, clinical pregnancy and ongoing pregnancy rates. Meanwhile, the implantation rate and live birth rate in frozen-thawed embryos were much higher than those of fresh embryo. The birth weight in the frozen-thawed ET group was greater than that of the FE group, and the low birth weight rate in FTE was lower than FE group. CONCLUSION: Our findings suggested a trend toward favouring frozen-thawed FTE might be a preferred transfer strategy for patients with IVF.

Shear Wave Elastography of Invasive Ductal Carcinoma: Correlations between Shear Wave Velocity and Histological Prognostic Factors.

The correlations between shear wave velocity (SWV) calculated from virtual touch tissue imaging quantification (VTIQ) technique and histological prognostic factors of invasive ductal carcinoma was investigated. A total of 76 breast tumors histologically confirmed as invasive ductal carcinomas were included in this study. SWV values were measured by VTIQ for each lesion preoperatively or prior to breast biopsy. The maximum values were recorded for statistical analysis. Medical records were reviewed to determine tumor size, histological grade, lymph node status and immunohistochemical results. Tumor subtypes were categorized as luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) positive and triple negative. The correlations between SWV and histological prognostic factors were analyzed. It was found that tumor size showed positive association with SWV (r=0.465, P<0.001). Larger tumors had significantly higher SWV than smaller ones (P=0.001). Histological grade 1 tumors had significantly lower SWV values than those with higher histological grade (P=0.015). The Ki67 expression, tumor subtypes and lymph node status showed no statistically significant correlations with SWV, although triple negative tumors and lymph node-positive tumors showed higher SWV values. It was concluded that tumor size was significantly associated with SWV. Higher histological grade was associated with increased SWV. There was no statistically significant correlations between SWV and other histological prognostic factors.

Androgen receptor expression identifies patient with favorable outcome in operable triple negative breast cancer.

In this study we sought to investigate the prevalence and prognostic value of androgen receptor (AR) status in operable triple-negative breast cancer (TNBC) patients. We collected the clinical data of 360 patients with TNBC, and found a positivity AR expression of 31.4% with a cut-off value of 10%. Tumors expressing the negative CK5/6 (P=0.013) and low Ki-67 (P=0.007) are more likely to have positive AR. In multivariate survival analysis, AR expression is correlated with increased DFS (HR=0.467, 95%CI 0.271-0.805; P=0.006) and OS (HR=0.488, 95%CI 0.267-0.894, P=0.020) independently. In addition, patients with AR+ tumors are more likely to have favorable outcome in patients with young, pre-menopausal, large tumor size, more node involvement (4+), high stage, high grade, vascular invasion+, P53+, CK5/6-, and higher Ki-67. Our study has indicated that the absence of AR might help to identify patients with relatively higher risk of disease relapse and death, and further clinical studies of anti-androgen agents are warranted to enrich the therapeutic strategy options for AR+ TNBCs.

Photoluminescent polyphosphazene nanoparticles for in situ simvastatin delivery for improving the osteocompatibility of BMSCs.

Nanomedicines have found promising applications in regulating the biological behaviors of cells because of the cell endocytosis effect. To enhance the osteogenic differentiation of bone marrow mesenchymal stromal cells (BMSCs), which is one of the key issues in relation to bone regeneration, a biodegradable simvastatin-bearing polyphosphazene prodrug was synthesized and made into nanoparticles (NPs). At the same time, photoluminescent tryptophan ethyl ester and hydrolyzable glycine ethyl ester were introduced as co-substituted side groups onto the polyphosphazene backbone. The resultant polymer, poly(simvastatin-co-ethyl tryptophanato-co-ethyl glycinato)phosphazene (PTGP-SIM), displayed the expected features of photoluminescence, degradability and sustained SIM release. Endocytosis of PTGP-SIM NPs by BMSCs and the location of internalized NPs, were visualized via the inherent photoluminescence features of PTGP-SIM. Thus, simvastatin was released inside the cells directly along with polymer degradation and could play a role in promoting osteogenic differentiation efficiently at quite a low local concentration. From the results, the present study suggested a very promising biomaterial for use as a flexible and functional carrier for bioactive components, which could find wide applications in relation to tissue regeneration.

HAND1 Loss-of-Function Mutation Causes Tetralogy of Fallot.

As the most prevalent form of birth defect in humans worldwide, congenital heart disease (CHD) is responsible for substantial morbidity and is still the leading cause of birth defect-related demises. Increasing evidence demonstrates that genetic defects play an important role in the pathogenesis of CHD, and mutations in multiple genes, especially in those coding for cardiac core transcription factors, have been causally linked to various CHDs. Nevertheless, CHD is a genetically heterogeneous disease and the genetic determinants underpinning CHD in an overwhelming majority of patients remain elusive. In the current study, genomic DNA was extracted from venous blood samples of 165 unrelated patients with CHD, and the coding exons and splicing junction sites of the HAND1 gene, which encodes a basic helix-loop-helix transcription factor essential for cardiovascular development, were sequenced. As a result, a novel heterozygous mutation, p.R118C, was identified in a patient with tetralogy of Fallot (TOF). The missense mutation, which was absent in 600 referential chromosomes, altered the amino acid that was completely conserved evolutionarily. Biological assays with a dual-luciferase reporter assay system revealed that the R118C-mutant HAND1 protein had significantly reduced transcriptional activity when compared with its wild-type counterpart. Furthermore, the mutation significantly decreased the synergistic activation of a downstream target gene between HAND1 and GATA4, another cardiac core transcription factor associated with TOF. To our knowledge, this is the first report on the association of a HAND1 loss-of-function mutation with enhanced susceptibility to TOF in humans. The findings provide novel insight into the molecular etiology underlying TOF, suggesting potential implications for the improved prophylactic and therapeutic strategies for TOF.

Cell studies of hybridized carbon nanofibers containing bioactive glass nanoparticles using bone mesenchymal stromal cells.

Bone regeneration required suitable scaffolding materials to support the proliferation and osteogenic differentiation of bone-related cells. In this study, a kind of hybridized nanofibrous scaffold material (CNF/BG) was prepared by incorporating bioactive glass (BG) nanoparticles into carbon nanofibers (CNF) via the combination of BG sol-gel and polyacrylonitrile (PAN) electrospinning, followed by carbonization. Three types (49 s, 68 s and 86 s) of BG nanoparticles were incorporated. To understand the mechanism of CNF/BG hybrids exerting osteogenic effects, bone marrow mesenchymal stromal cells (BMSCs) were cultured directly on these hybrids (contact culture) or cultured in transwell chambers in the presence of these materials (non-contact culture). The contributions of ion release and contact effect on cell proliferation and osteogenic differentiation were able to be correlated. It was found that the ionic dissolution products had limited effect on cell proliferation, while they were able to enhance osteogenic differentiation of BMSCs in comparison with pure CNF. Differently, the proliferation and osteogenic differentiation were both significantly promoted in the contact culture. In both cases, CNF/BG(68 s) showed the strongest ability in influencing cell behaviors due to its fastest release rate of soluble silicium-relating ions. The synergistic effect of CNF and BG would make CNF/BG hybrids promising substrates for bone repairing.

Acetabular Labral Reconstruction With Autologous Tendon Tissue in a Porcine Model: In Vivo Histological Assessment and Gene Expression Analysis of the Healing Tissue.

BACKGROUND: Acetabular labral reconstruction with autologous tendons is the preferred method for treating a severely damaged labrum. However, the healing process of implants remains unknown. Similar to the human acetabular labrum, the porcine acetabular labrum is a fibrocartilage-like tissue. PURPOSE: This study aimed to characterize the histological healing process and gene expression profile of implants in a porcine model of acetabular labral reconstruction. STUDY DESIGN: Descriptive laboratory study. METHODS: Eighteen pigs were included in this study. The pigs underwent unilateral acetabular labral reconstruction. A 1.0 cm-long defect was made at the site of the anterior (cranial) dorsal labrum, which was repaired using an autologous mesogluteus tendon. The pigs were sacrificed at 12 and 24 weeks postoperatively. The implants were subjected to histological assessment and gene expression analysis. The cell phenotype of the implants was visualized using paraffin-embedded sections. RESULTS: Macroscopic observations revealed that at 12 weeks, 8 of 9 implants partially filled the labral defect; by contrast, at 24 weeks, 6 of 9 implants fully filled and 3 implants partially filled the labral defects. Oval- or round-shaped fibrochondrocytes were found in the implants at 12 and 24 weeks. The matrix staining results showed that proteoglycan and collagen types 1 and 2 were more evident in the implants at 24 weeks than at 12 weeks. Gene expression analysis results revealed that COL2A1 and COL3A1 were expressed by the implants to a higher extent at 24 weeks than at 12 weeks; COL2A1 and COL3A1 were also expressed to a higher extent in the implants than in the native tendon. CONCLUSION: On the basis of the results of histological assessment and gene expression analysis, autologous tendon tissue for acetabular labral reconstruction can fully or partially fill labral defects and converts to fibrocartilage, which is rich in proteoglycan and collagen types 1 and 2, at 24 weeks in a porcine model. CLINICAL RELEVANCE: Autologous tendon tissue can be considered as a viable option for acetabular labral reconstruction.

Transplantation of adipose-derived stem cells is associated with neural differentiation and functional improvement in a rat model of intracerebral hemorrhage.

AIMS: To examine whether transplantation of adipose-derived stem cells (ADSCs) induces neural differentiation and improves neural function in a rat intracerebral hemorrhage (ICH) model. METHODS: Adipose-derived stem cells cells were isolated from inguinal fat pad of rat. ICH was induced by injection of collagenase type IV into the right basal ganglia of rat. Forty-eight hours after ICH, ADSCs cells (10 µL of 2-4 × 10(7) cells/mL) were injected into the right lateral cerebral ventricle. The differentiation of ADSCs was detected in vitro and in vivo. The neural function was evaluated with Zea Longa 5-grade scale at day 1, 3, 7, 14, or 28. RESULTS: Our data demonstrated that ADSCs differentiated into cells that shared the similarities of neurons or astrocytes in vitro. Transplantation of ADSCs decreased cell apoptosis and the transplanted ADSCs were able to differentiate into neuron-like and astrocyte-like cells around the hematoma, accompanied with upregulation of vascular endothelial growth factor expression and improvement of neural function. CONCLUSIONS: Our data suggest that transplantation of ADSCs could be a therapeutic approach for ICH stroke.

[Redox factor 1 increases proliferation of neonatal rat cardiac fibroblasts].

OBJECTIVE: To investigate the function of REF1 in the proliferation and collagen synthesis of neonatal rat cardiac fibroblasts, and the underlying mechanisms. METHODS: Neonatal rat cardiac fibroblasts were transfected with the adenoviral vector containing rat wild type Ref1 (Ad-Ref1) or mutated Ref1 (Ad-mutRef1). The mutations resulted in Cys to Ala at amino acids 65 and 93, which eliminated the redox function of the REF1 protein. MTT was used to check the cell viability and flow cytometry was used to analyze the cell proliferation with the count of cell numbers and the percentage of cells in S phase of the cell cycle. The expressions of Ref1, collagen I (Col I) and collagen III (Col III) were determined by RT-PCR and Western blot. The translocation of REF1 was examined by fluorescence staining and revealed under fluorescence microscope. Electrophoretic mobility shift assay (EMSA) was used to check the effect of REF1 on AP1 DNA binding ability. The high glucose medium (25 mmol/L) was applied to culture cardiac fibroblasts. The effect of high glucose on AP1 DNA binding activity, the expression and translocation of REF1 were examined. RESULTS: MTT analysis showed that Ad-Ref1 promoted the relative viability of cardiac fibroblasts (0.671+/-0.044 vs control 0.364+/-0.007, n=6, P<0.01). The percentage of cells in S phase of the cell cycle was increased significantly in the Ad-Ref1 transfected cells (16.8%+/-0.62% vs control 9.04%+/-0.43%, n=3, P<0.05), as demonstrated by flow cytometry analysis. The expressions of Col I and Col III at mRNA level were increased when cells transfected with Ad-Ref1, while Ad-mutRef1 did not show such effects. Compared with the redox-deficient mutant Ad-mutRef1 (C65/93A), EMSA results demonstrated that Ad-Ref1 resulted in a marked increase in AP1 DNA binding. We also found that the cardiac fibroblasts cultured in high glucose (25 mmol/L) medium resulted in an increase in AP1 DNA binding activity, which was similar as seen in Ad-Ref1 transfected cells. There was also an increased accumulation of nuclear REF1 protein when cells were cultured in high glucose medium, although the expressions of REF1 at both mRNA and protein levels were not affected. CONCLUSION: REF1 can increase proliferation and collagen synthesis of cardiac fibroblasts, which may be related to its ability to up-regulate AP1 DNA binding.

Effects of different glycerol feeding strategies on S-adenosyl-l-methionine biosynthesis by P(GAP)-driven Pichia pastoris overexpressing methionine adenosyltransferase.

Methionine adenosyltransferase (MAT) was overexpressed within Pichia pastoris employing the promoter of glyceraldehyde-3-phosphate dehydrogenase gene (P(GAP)), to biosynthesize S-adenosyl-l-methionine (SAM). Effects of five glycerol feeding tactics on MAT activity were first investigated. Strategies A-C were based on limited feeding correlated with dissolved oxygen (DO) at 50.0%, 25.0% and 0.0%, respectively. For strategies D and E, unlimited supplementation was executed by pulsed feeding mode. Gradual decline (2-0%) (w:v) of the residual glycerol level was shown between any two pulses in strategy D, while a nearly stable content (2%) throughout fed-batch cultivation with strategy E. With shifting strategies A-E in alphabetical order, gradual improvements of MAT activities were achieved, with the maximum of 9.05Ug(-1) dried biomass for strategy E, since the specific glycerol consumption rate (F(G)) ascended due to the elevated specific oxygen uptake rate (qO(2)). The success was ascribed to the enhancement of oxygen transfer rate (OTR), because 2% glycerol improved oxygen saturation content in broth (C*) and volumetric oxygen transfer coefficient (k(L)a). Strategy E also led to the highest values of ATP and biomass besides MAT. Consequently, the highest SAM yield and volumetric level were obtained at 0.058gg(-1) and 9.26gl(-1), respectively.