Monolayer MSi2P4 (M = V, Nb, and Ta) as Highly Efficient Sulfur Host Materials for Lithium-Sulfur Batteries.

Despite the high capacity and low cost of lithium-sulfur (Li-S) batteries, their commercialization is greatly blocked by multiple bottlenecks including the shuttle effect of lithium polysulfides (LiPSs), poor conductivity of sulfur, and sluggish reaction kinetics. Herein, we propose novel two-dimensional MSi2P4 (M = V, Nb, and Ta) monolayers as promising sulfur hosts to improve the Li-S battery performance. Our calculations show that MSi2P4 monolayers offer moderate binding strengths to the polysulfides, which are expected to effectively inhibit the LiPS shuttling and dissolution. Moreover, the conductive properties of the MSi2P4 systems are well maintained after LiPS adsorption, eliminating the insulating nature of sulfur species. Remarkably, MSi2P4 monolayers exhibit superior electrocatalytic activity for the sulfur reduction reaction and the Li2S decomposition reaction, which considerably lowers the energy barriers of LiPS conversions during discharge and charge, thus ensuring the fast redox kinetics and high sulfur utilization of Li-S batteries. This study pioneers the application of MSi2P4 monolayers as highly efficient sulfur host materials for Li-S batteries and affords insights for further development of advanced Li-S batteries.

A rapid sap-direct reverse transcription-polymerase chain reaction method for detection of dendrobium viroid in Dendrobium plants.

Dendrobium viroid (DVd) was first reported in China in 2020, and it is the only viroid known to infect Orchidaceae family plants. In this study, we developed a simple reverse transcription-polymerase chain reaction (RT-PCR) method for the rapid detection of DVd in Dendrobium plants. When extracting the sap template from the leaves, they are first clamped between two layers of plastic film, and the sap is pressed out and collected with a pipette. Using this sap, DVd was detected by dot-blot and RT-PCR methods and, the expected amplicons were confirmed by sequencing analysis. The batch analysis of field samples revealed that this method can be used to detect DVd rapidly. The detection method also reduces cross-contamination between different samples and minimizes false positives. Thus, this sap-direct RT-PCR method allows effective and rapid DVd detection in the study of Orchidaceae plants.

[Distribution of the anterior corneal astigmatism in over 140 000 patients with age-related cataract].

Objective: To analyze the distribution characteristics of the anterior corneal astigmatism in 140 000 cataract patients from 18 hospitals in China. Methods: Retrospective study. A total of 143 889 patients (143 889 right eyes) over the age of 40 years with age-related catarac were admitted to 18 Aier eye hospitals in China from July 2015 to October 2018. The average values of the three measurements of the magnitude of anterior corneal astigmatism, the meridian of corneal astigmatism, anterior chamber depth, corneal refractive power, and axial length measured by IOLMaster 500 were obtained. The data acquisition method of each sub-center was to collect and analyze the electronic case data in accordance with the inclusion and exclusion criteria, and to provide them for the sponsor Wuhan Aier Eye Hospital. Non-normal distribution data are presented as M (P25, P75). Mann-Whitney test, Kruskal-Wallis test, Chi-square test were used to analyze the distribution differences of the magnitude of corneal astigmatism and the meridian of corneal astigmatism in gender, age, anterior chamber depth, corneal refractive power and axial length. Results: Among the 143 889 patients, 84 319 were females and 59 570 were males, the median age was 72 (65, 78) years old, the median corneal astigmatism was 0.84 (0.51, 1.33) D; the corneal astigmatism was ≥0.75 D in 80 895 patients (56.22%) and was ≥1.00 D in 57 304 patients (39.83%). The median corneal astigmatism was 0.87 (0.53, 1.37) D in women and 0.82 (0.50, 1.29) D in men; with statistical difference (U=-14.891; P<0.05). The proportion of with-the-rule (WTR) astigmatism was 33.26% (28 046/84 319) for women and 34.26% (20 408/59 570) for men; The proportion of against-the-rule (ATR) astigmatism was 49.08% (41 385/84 319) for women and 46.91% (27 945/59 570) for men, with statistical difference (χ²=70.913; P<0.05). With the increase of age, the magnitude of corneal astigmatism first decreased from 0.94 (0.57, 1.48) D to 0.75 (0.46, 1.18) D, and then increased to 1.19 (0.74, 1.79) D, with statistical difference (H=1 263.438; P<0.05), and the change was at 61 to 70 years old. With the increase of age, the proportion of WTR astigmatism decreased from 77.50% (396/511) to 12.50% (3/24), the proportion of ATR astigmatism increased from 11.15% (57/511) to 79.07% (34/43), and the proportion of oblique astigmatism changed little from 17.02% (16/94) to 19.92% (245/1 230), the distribution difference was significant (χ²=10 174.496; P<0.05). As the anterior chamber became shallow, the magnitude of corneal astigmatism significantly increased from 0.82 (0.51, 1.31) D to 1.05 (0.61, 1.56) D, and the proportion of ATR astigmatism increased from 47.32% (60 207/127 227) to 51.69% (184/356) (H=409.961, χ²=120.995, both P<0.05). With the corneal refractive power rising, the magnitude of corneal astigmatism increased from 0.80 (0.49, 1.33) D to 0.95 (0.58, 1.53) D, the proportion of ATR astigmatism decreased from 52.84% (4 963/9 392) to 39.97% (9 023/22 577); the difference was significant (H=808.562, χ²=752.147, both P<0.05). When the axial length was>25.00 mm, the magnitude of corneal astigmatism was highest [1.04 (0.62, 1.65) D], and the proportion of ATR astigmatism was also highest [49.00% (10 964/22 376)]; the difference was significant (H=2 071.198, χ²=131.130, all P<0.05). Conclusions: The meridian of corneal astigmatism in middle-aged and elderly cataract patients is mainly ATR astigmatism. With the increasing of age, the magnitude of corneal astigmatism decreases first and then increases. The turning point from the proportion of WTR astigmatism to the proportion of ATR astigmatism is 65 years old. The shallower the anterior chamber is, the more the magnitude of corneal astigmatism and the proportion of ATR astigmatism increase. When the axial length is>25.00 mm, both the magnitude of corneal astigmatism and the proportion of ATR astigmatism reach the peak. (Chin J Ophthalmol, 2021, 57: 56-62).

BLACAT1 is negatively associated with prognosis in patients with NSCLC and inhibits cell progression, metastasis and epithelial-mesenchymal transition through down-regulating Wnt/ß-catenin signaling pathway.

OBJECTIVE: To evaluate the clinical significance and molecular mechanism of bladder cancer-associated transcript 1 (BLACAT1) in non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Overall, 156 NSCLC cancer patients were recruited and divided into high and low BLACAT1 level group by the median value of BLACAT1 expression. The associations of BLACAT1 expression with the clinicopathological features and prognosis were evaluated. A series of in vitro assays were performed to explore the role of BLACAT1 on NSCLC progression and metastasis. RESULTS: Patients with high BLACAT1 expression had shorter overall survival and progression-free survival than those with low BLACAT1 expression. Multivariate analyses showed that BLACAT1 was an independent prognostic factor of survival in NSCLC patients. In vitro assays showed that the downregulation of BLACAT1 significantly suppressed cell progression, migration, and invasion. The epithelial-mesenchymal transition was also inhibited when BLACAT1 was silenced, indicated by an increase in E-cadherin expression and a decrease in vimentin expression by mediating Wnt/ß-catenin signaling pathway. CONCLUSIONS: BLACAT1 should be a potential prognostic biomarker and therapeutic target for NSCLC.

[Midterm outcomes of surgical treatment of traumatic severe tricuspid insufficiency].

Objective: To investigate the indication and midterm outcomes of surgical treatment of traumatic tricuspid insufficiency. Methods: Totally 19 patients with traumatic tricuspid insufficiency who underwent surgical treatment at Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University from January 2002 to January 2018 were included in this retrospective study. There were 12 male and 7 female patients, aged (43.1±12.9) years (range: 17-68 years). The main causes of traumatic tricuspid insufficiency included blunt chest trauma following high-speed vehicle accidents (17 patients) and high-fall trauma (2 patients). The preoperative New York Heart Association functional class was class Ⅱ in 5 patients, class Ⅲ in 12 patients, and class Ⅳ in 2 patients. The mechanism of tricuspid insufficiency included anterior chordal rupture in 9 patients, anterior papillary muscle rupture in 3 patients, anterior and posterior chordal or papillary muscle rupture in 4 patients, laceration of leaflet combined with chordal rupture in 2 patients and infection combined with anterior papillary muscle rupture in 1 patient. Anular dilation and enlargement of the right ventricle were observed in all the patients. Paired t test was used to evaluate the echocardiogratic results at preoperation, postoperation and follow-up. Independent sample rank sum test was used to evaluate the intervals between trauma and surgery in tricuspid valve repair group and tricuspid valve replacement group. Results: Tricuspid valve repair was successful in 8 patients, and 11 patients underwent valve replacement. Among the patients who underwent valve replacement, 6 patients received mechanical valve and 5 received bioprosthetic valve. The interval from trauma to surgery of the valve repair group and valve replacement group were 8.5(10.0) months (range: 0.1-13.0 months) and 72.0 (108.0) months (range: 2.0-228.0 months), respectively. Concomitant procedures included debridement in scalp trauma (1 patient), internal fixation of femoral fracture (1 patient). One patient died from liver failure 10 days after operation and the remaining patients survived. Eighteen patients were followed up for (94±50) months, 15 patients were in New York Heart Association functional class Ⅰ and 3 patients in class Ⅱ. One patient received redo-tricuspid valve replacement because of mechanical valve failure at the 11 years of follow-up. Conclusions: The midterm outcomes of surgical treatment of severe traumatic tricuspid insufficiency were satisfactory. Early diagnosis and surgical invention were recommended to achieve successful valve repair.

Aggregation between xanthan and nonyphenyloxypropyl beta-hydroxyltrimethylammonium bromide in aqueous solution: MesoDyn simulation and binding isotherm measurement.

The aggregation behavior of nonyphenyloxypropyl beta-hydroxyltrimethylammonium bromide (C9phNBr) and xanthan (XC) in aqueous solution was investigated by MesoDyn density functional simulation and binding isotherm measurement. The process of aggregate formation and the aggregate morphology are reported. The formation of aggregates includes three stages and the morphology of XC-C9phNBr aggregates is rodlike or ellipsoidal. The effects of temperature and XC concentration on the aggregation are analyzed. Results indicate that the formation of aggregates is an exothermic process, and their formation becomes more difficult and the formation rate decreases with increasing temperature. The formation of aggregates is also related to XC concentration, and it becomes much more difficult when the concentration of XC is higher than 20 vol %. The simulation results agree with binding isotherms of C9phNBr to XC obtained via the potentiometric titration method, which shows a typical cooperative binding between C9phNBr and XC.

[Synergistic effect of the expression of p16INK4 gene and retinoblastoma gene in lung cancer].

In order to clarify the frequency of p16INK4 gene inactivation and its relationship with retinoblastoma (Rb) gene expression in non-small cell lung cancer, in situ double hybridization was established with Bio-labelled Rb cDNA probe and Dig-lablled p16INK4 cDNA probe, and immunohistochemistry was carried out with polyclone rabbit antibodies to human p16INK4 and Rb protein. The results showed that positive hybridization of p16INK4 mRNA showed blue with the detecting system of alkiline phosphatase NBT/BCIP, positive hybridization of Rb mRNA showed red with the detecting system of HPR-AEC. The negative ratios of p16INK4 and Rb gene transcription were 22.6%(7/31) and 16.1%(5/31). The results of immunohistochemistry showed that the negative ratio of p16INK4 protein was 42%(13/31) with p16INK4 polyclone antibody, the negative ratio of pRb was 19.4%(6/31) with polyclone antibody. The data indicated that p16INK4 gene and Rb gene are synergistic in the progression of lung cancer, p16INK4 gene plays a significant role in the development of non-small cell lung cancer.

Molecular characterization in the VP7, VP4 and NSP4 genes of human rotavirus serotype 4 (G4) isolated in Japan and Kenya.

The VP7, VP4 and NSP4 genes of human rotavirus serotype 4 (G4) were analyzed to investigate intraserotypic variations. The techniques used included reverse transcription polymerase chain reaction with subtype specific primers, restriction fragment length polymorphism analysis and sequence analysis. Twelve isolates (nine from Japan and three from Kenya) and two standard strains (Hochi, Odelia) were G4A P[8] Wa group NSP4. A standard strain (ST3) was G4A P[6] Wa group NSP4 and a strain (VA70) was G4B P[8] Wa group NSP4. These results show G4 rotaviruses can be divided into three combinations at the moment.

Evidence of HIV type 1 glycoprotein 120 binding to recombinant N-methyl-D-aspartate receptor subunits expressed in a baculovirus system.

Activation of the N-methyl-D-aspartate (NMDA) receptor by HIV-1 envelope glycoprotein 120 (gp120) is thought to represent at least one of the pathways causing neuronal damage in AIDS patients. In the present study, recombinant gp120 binding to NMDA receptor subunits expressed in a baculovirus system was examined by immunocytochemistry and a binding assay, using horseradish peroxidase (HRP)-conjugated and 125I-labeled recombinant gp120, respectively. We found that recombinant gp120 binds to Sf21 cells expressing epsilon1/zeta1 or epsilon2/zeta1 combined NMDA receptor subunits, but not to Sf21 cells infected with mock virus or Sf21 cells expressing a single epsilon1, epsilon2, or zeta1 NMDA receptor subunit. The binding was strongly blocked by unlabeled recombinant gp120, monoclonal anti-HIV-1 gp160 antibody, and a mixture of anti-epsilon1/epsilon2 and anti-zeta1 antibodies. The same results were obtained by flow cytometric analysis. These data suggest that HIV-1 gp120 may directly bind to the NMDA receptor. This evidence enhances our understanding of the mechanism of HIV-1-induced neuronal damage in AIDS patients.

Genetic variation in the VP4 and NSP4 genes of human rotavirus serotype 3 (G3 type) isolated in China and Japan.

Sequence analyses of the VP4 and NSP4 genes were performed on twenty human isolates of serotype G3 rotavirus obtained from China and Japan. One isolate from China, CHW17, possessed P[4] genotype VP4 and KUN group NSP4 genes which are associated with G2. One isolate (02/92) from Japan, which was shown to have a wider spacing between RNA segments 10 and 11 by RNA polyacrylamide gel electrophoretic analysis like AU-1, possessed P[9] genotype VP4 and AU-1 group NSP4 genes. The other isolates had P[8] genotype VP4 and Wa group NSP4 genes. While the nucleotide sequence conservation among the G3 VP7 genes was more than 79% (Wen et al, Arch. Virol., 1997, 142: 1481-1489), the conservation of VP4 and NSP4 genes in the same genotypes or groups was more than 85%.

Intranasal administration of human immunodeficiency virus type-1 (HIV-1) DNA vaccine with interleukin-2 expression plasmid enhances cell-mediated immunity against HIV-1.

DNA vaccine against human immunodeficiency virus type-1 (HIV-1) can induce substantial levels of HIV-1-specific humoral and cell-mediated immunity. To develop more potent HIV-1 DNA vaccine formulations, we used a murine model to explore the immunomodulatory effects of an interleukin-2 (IL-2) expression plasmid on an HIV-1 DNA vaccine following intranasal administration of the combination. When the vaccine and expression plasmid were incorporated into cationic liposomes and administered to mice, the HIV-1-specific delayed-type hypersensitivity response and cytotoxic T lymphocyte activity were significantly increased. Restimulated immune lymphoid cells showed enhanced production of both IL-2 and interferon-gamma and reduced secretion of IL-4. The level of total antibody to HIV-1 antigen was not greatly changed by coadministration of the DNA vaccine and IL-2 expression plasmid. An analysis of serum HIV-1-specific IgG subclasses showed a significant drop in the IgG1/IgG2a ratio in the group that received the plasmid-vaccine combination. These results demonstrate that the IL-2 expression plasmid strongly enhances the HIV-1-specific immune response via activation of T helper type-1 cells.

Inhibition of invasion of HT1080 sarcoma cells expressing recombinant plasminogen activator inhibitor 2.

Plasminogen activators (PA) elaborated by tumor cells play an important role in the complex process of tissue invasion and metastasis. In the present study the effect of the PA inhibitor type 2 (PAI-2) on tissue invasion in vitro and in vivo was investigated. Clones either expressing (B-) or not expressing the endogenous PAI-2 gene (C+) were isolated from the human HT1080 fibrosarcoma cell line and transfected with full-length PAI-2 cDNA. Recombinant PAI-2 (rPAI-2) expressed by these cells completely inhibited receptor-bound urokinase activity and partially neutralized secreted PA activity. Degradation of extracellular matrix proteins by these transfected cells was markedly decreased when compared to mock or untransfected control cells. The rPAI-2-expressing cells did not penetrate a multilayer of rat smooth muscle cells in vitro, which was readily invaded and destroyed by control cells. The PAI-2 transfectants remained tumorigenic in athymic/nude mice, but tumors originating from these cells showed the presence of a thick, collagenous capsule absent in tumors formed by control cells. Thus, expression of rPAI-2 in HT1080 cells resulted in neutralization of receptor-bound urokinase with subsequent inhibition of matrix protein degradation and invasion in vitro and induction of a thick, peritumoral capsule in vivo.

Complex expression of the genes coding for plasminogen activators and their inhibitors in HeLa-smooth muscle cell hybrids.

As cells progress through the multistep process of neoplastic transformation, they eventually acquire the property of invasive behavior. Although both plasminogen activators (PA) and their inhibitors (PAI) contribute to this process, their regulation in normal and transformed cells remains poorly defined. Because somatic cell hybrids provide useful tools for examining the transformation pathway, tumorigenic and invasive HeLa cells were fused with human normal vascular smooth muscle cells and tested for invasion-related parameters, including the expression of PA and PAI genes, and matrix degradation. Both parental cell lines produced large amounts of PAI activities with no detectable PA in either cellular or secreted form. Opposite findings were obtained with the hybrid cell lines, which demonstrated the presence of receptor-bound and secreted PA but absence of enzymatically measurable PAI activities. Both urokinase-type and tissue-type PA were found in cell-associated and secreted form in the hybrid cells. In addition, expression of the urokinase-type PA receptor gene was found in the three hybrid cells and the vascular smooth muscle cells but not in the HeLa cells. Expression of active, receptor-bound and secreted PA provided the nontumorigenic hybrid cells with the enzymatic tools to degrade extracellular proteins in a plasminogen-dependent manner. Thus, the hybrid cells lost tumorigenicity while retaining the tissue-degrading capability of HeLa cells. These hybrid cell lines should prove to be important reagents for investigating the complex regulatory control of PA and PAI gene expression.

Cell cycle-dependent regulation of phosphorylation of the human retinoblastoma gene product.

The human retinoblastoma gene (RB1) encodes a protein (Rb) of 105 kilodaltons that can be phosphorylated. Analysis of Rb metabolism has shown that the protein has a half-life of more than 10 hours and is synthesized at all phases of the cell cycle. Newly synthesized Rb is not extensively phosphorylated (it is "underphosphorylated") in cells in the G0 and G1 phases but is phosphorylated at multiple sites at the G1/S boundary and in S phase. HL-60 cells that were induced to terminally differentiate by various chemicals lost their ability to phosphorylate newly synthesized Rb at multiple sites when cell growth was arrested. These findings suggest that underphosphorylated Rb may restrict cell proliferation.