Protein expression patterns and metal metabolites in a protogynous hermaphrodite fish, the ricefield eel (Monopterus albus)

BACKGROUND

The ricefield eel Monopterus albus undergoes a natural sex change from female to male during its life cycle, and previous studies have shown the potential mechanisms of this transition at the transcriptional and protein levels. However, the changes in protein levels have not been fully explored, especially in the intersexual stage.

RESULTS

In the present study, the protein expression patterns in the gonadal tissues from five different periods, the ovary (OV), early intersexual stage gonad (IE), middle intersexual stage gonad (IM), late intersexual stage gonad (IL), and testis (TE), were determined by untargeted proteomics sequencing. A total of 5125 proteins and 394 differentially expressed proteins (DEPs) were detected in the gonadal tissues. Of the 394 DEPs, there were 136 between the OV and IE groups, 20 between the IM and IE groups, 179 between the IL and IM groups, and 59 between the TE and IL groups. Three candidate proteins, insulin-like growth factor 2 mRNA-binding protein 3 isoform X1 (Igf2bp3), triosephosphate isomerase (Tpi), and Cu-Zn superoxide dismutase isoform X1 [(Cu-Zn) Sod1], were validated by western blotting to verify the reliability of the data. Furthermore, metal metabolite-related proteins were enriched in the IL vs. IM groups and TE vs. IL groups, which had close relationships with sex change, including Cu2+-, Ca2+-, Zn2+- and Fe2+/Fe3+-related proteins. Analysis of the combined transcriptome data revealed consistent protein/mRNA expression trends for two metal metabolite-related proteins/genes [LOC109953912 and calcium Binding Protein 39 Like (cab39l)]. Notably, we detected significantly higher levels of Cu2+ during the sex change process, suggesting that Cu2+ is a male-related metal metabolite that may have an important function in male reproductive development.

CONCLUSIONS

In summary, we analyzed the protein profiles of ricefield eel gonadal tissues in five sexual stages (OV, IE, IM, IL, and TE) and verified the plausibility of the data. After preforming the functional enrichment of metal metabolite-related DEPs, we detected the contents of the metal metabolites Zn2+, Cu2+, Ca2+, and Fe2+/Fe3+ at these five stages and screened for (Cu-Zn) Sod1 and Mmp-9 as possible key proteins in the sex reversal process.

[Epidemiological analysis of influenza during COVID-19 epidemic in Jiangsu Province from 2020 to 2022]

By analyzing the epidemic characteristics of influenza during the COVID-19 epidemic in Jiangsu Province from 2020 to 2022, it found that 90 721 influenza-like case samples were collected in Jiangsu Province from 2020 to 2022, of which 6 732 were nucleic acid-positive samples, with an average positive detection rate of 7.4% in three years. The annual positive detection rate presented a U-shaped distribution, with positive detection rates of 4.4%, 3.2% and 14.7%, respectively, with statistically significant differences (χ2=12 126.00, P<0.001). During the seasonal peak period of influenza from 2020 to 2022, there was a significant decrease in the intensity of the two influenza activity peaks that occurred before the virus became fully prevalent in the population. The first peak occurred from January to February 2020, and the positive detection rate of influenza nucleic acid decreased from 54.4% (317/583) in the third week to 2.1% (12/584) in the eighth week, with a statistically significant difference (χ2=394.49, P<0.001). The second occurred in December 2022, and the positive detection rate of influenza nucleic acid decreased from 14.9% (90/605) at the 49th week to 1.9% (11/572) at the 52nd week, with a statistically significant difference (χ2=62.88, P<0.001). The influenza epidemic in Jiangsu Province from 2020 to 2022 had obvious seasonal characteristics, and the distribution differences of influenza virus-positive cases in each month were statistically significant (χ2=858.00, P<0.001), with two epidemic peaks each year: winter, spring (December to March of the following year), and summer, and autumn (July to November). The epidemic strains were the B-V strain and seasonal H3 strain, respectively. There was a statistically significant difference in the positive detection rate of influenza cases detected in different age groups (χ2=60.00, P<0.001). The age group between 5 and 14 years old had the highest influenza-positive detection rate (10.4%), while the age group≥60 years old had a relatively low influenza-positive detection rate (5.1%). The positive detection rate decreased with the increase in the age group (Ztrend=12.82, P<0.001).

Machine-learning models for prediction of sepsis patients mortality

OBJECTIVES

Sepsis is an infection-caused syndrome, that leads to life-threatening organ damage. We aim to develop machine learning models with large-scale data to predict sepsis patients' mortality.

DESIGN

we extracted sepsis patients from two databases, Medical Information Mart for Intensive Care IV (MIMIC-IV) as a train set and Philips eICU Collaborative Research Database as a test set.

SETTING

ICUs in multicenter hospitals in the USA during 2012-2019.

PATIENTS OR PARTICIPANTS

A total of 21,680 sepsis-3 patients are included in the study, in which, 3771 patients were dead and 17,909 survived during hospitalization, respectively.

INTERVENTIONS

No interventions.

MAIN VARIABLES OF INTEREST

Basic information, examination items during hospitalization and some medication and treatment information are incorporated into analyzed. Seven different models were built with a Support vector machine, Decision Tree Classifier, Random Forest, Gradients Boosting, Multiple Layer Perception, Xgboost, light Gradients Boosting to predict dead or live during hospitalization.

RESULTS

Algorithms with an AUC value in the test set of the top three: light GBM, GBM, Xgboost. Considering the performance of the training set and the test set, the light GBM model performs best, and then the parameters of the model were adjusted, after that the AUC value was 0.99 in the train set, 0.96 in the test set, respectively.

CONCLUSIONS

Models built with light GBM algorithm from real-world sepsis patients from electronic health records accurately predict whether sepsis patients are dead and can be incorporated into clinical decision tools to enhance the prognosis of the patient and prevent adverse outcomes.

Fish Community Structure and Biomass Particle-Size Spectrum in the Upper Reaches of the Jinsha River (China)

To understand the characteristics of the fish community structure and biomass particle-size spectrum in the upper reaches of the Jinsha River, fish and environmental surveys were conducted in 21 segments of the upper reaches of the Jinsha River in September 2019 and June 2020. A total of 4062 fish belonging to 2 orders, 5 families, 18 genera, and 28 species were collected. Among them, Cyprinidae fish were the most abundant (14 species), accounting for 50.00%. The Shannon index and Pielou evenness index values varied from 0.402-1.770 and 0.254-0.680, respectively. The dominant species of fish were Triplophysa stenura, Schizothorax wangchiachii, and Schizopygopsis malacanthus. Redundancy analysis (RDA) was used to analyse the relationship between the fish community and environmental factors. Velocity, altitude, and dissolved oxygen were the main influencing factors of fish community structure differences in the upper reaches of the Jinsha River. The abundance/biomass curves showed that the fish communities in the upper reaches of the Jinsha River were moderately or severely disturbed. The standardized biomass particle-size spectrum of fish showed that the degree of disturbance of fish in tributaries was much lower than that in the main stream. Compared with the historical data, the fish community structure in the Jinsha River has changed significantly, with the number of exotic species increasing, and the individual fish showing miniaturization and younger ages. It is suggested that habitat conservation strategies be adopted in the upper tributaries of the Jinsha River to provide a reference for the restoration of fishery resources and the conservation of fish diversity in the Yangtze River.

[Effect of P62 on the migration and motility of human epidermal cell line HaCaT in high glucose microenvironment and its mechanism]

Objective: To investigate the effect of P62 on the migration and motility of human epidermal cell line HaCaT in high glucose microenvironment and its possible molecular mechanism, so as to explore the mechanism of refractory diabetic foot wound healing. Methods: The method of experimental research was used. HaCaT cells in logarithmic growth phase was taken for experiment. The cells were collected and divided into normal control group (culture solution containing glucose with final molarity of 5.5 mmol/L) and high glucose (culture solution containing glucose with final molarity of 30.0 mmol/L) 24 h group, high glucose 48 h group, and high glucose 72 h group according to the random number table (the same grouping method below). The cells in normal control group were routinely cultured for 72 h, cells in high glucose 72 h group were cultured with high glucose for 72 h, cells in high glucose 48 h group were routinely cultured for 24 h then cultured with high glucose for 48 h, cells in high glucose 24 h group were routinely cultured for 48 h then cultured with high glucose for 24 h. Then the protein expression of P62 was detected by Western blotting. The cells were collected and divided into normal control group and high glucose group. After being correspondingly cultured for 48 h as before, the protein expression of P62 was detected by immunofluorescence method (indicated as green fluorescence). The cells were collected and divided into negative control small interfering RNA (siRNA) group, P62-siRNA-1 group, P62-siRNA-2 group, and P62-siRNA-3 group, and transfected with the corresponding reagents. At post transfection hour (PTH) 72, the protein expression of P62 was detected by Western blotting. The cells were collected and divided into normal glucose+negative control siRNA group, normal glucose+P62-siRNA group, high glucose+negative control siRNA group, and high glucose+P62-siRNA group. After the corresponding treatment, the protein expression of P62 was detected by Western blotting at PTH 72 h, the cell migration rate was detected and calculated at 24 h after scratching by scratch test, with the number of samples being 9; and the range of cell movement was observed and the trajectory velocity was calculated within 3 h under the living cell workstation, with the number of samples being 76, 75, 80, and 79 in normal glucose+negative control siRNA group, normal glucose+P62-siRNA group, high glucose+negative control siRNA group, and high glucose+P62-siRNA group, respectively. The cells were collected and divided into normal glucose+phosphate buffered solution (PBS) group, high glucose+PBS group, and high glucose+N-acetylcysteine (NAC) group. After the corresponding treatment, the protein expression of P62 at 48 h of culture was detected by Western blotting and immunofluorescence method, respectively. Except for scratch test and cell motility experiment, the number of samples was all 3 in the rest experiments. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: Compared with the protein expression in normal control group, the protein expressions of P62 of cells in high glucose 24 h group, high glucose 48 h group, and high glucose 72 h group were significantly increased (P<0.01). At 48 h of culture, the green fluorescence of P62 of cells in high glucose group was stronger than that in normal control group. At PTH 72, compared with the protein expression in negative control siRNA group, the protein expressions of P62 of cells in P62-siRNA-1 group, P62-siRNA-2 group, and P62-siRNA-3 group were significantly decreased (P<0.01). At PTH 72, compared with the protein expression in normal glucose+negative control siRNA group, the protein expression of P62 of cells in normal glucose+P62-siRNA group was significantly decreased (P<0.01), while the protein expression of P62 of cells in high glucose+negative control siRNA group was significantly increased (P<0.01); compared with the protein expression in high glucose+negative control siRNA group, the protein expression of P62 of cells in high glucose+P62-siRNA group was significantly decreased (P<0.01). At 24 h after scratching, compared with (55±7)% in normal glucose+negative control siRNA group, the cell migration rate in normal glucose+P62-siRNA group was significantly increased ((72±14)%, P<0.01), while the cell migration rate in high glucose+negative control siRNA group was significantly decreased ((37±7)%, P<0.01); compared with that in high glucose+negative control siRNA group, the cell migration rate in high glucose+P62-siRNA group was significantly increased ((54±10)%, P<0.01). Within 3 h of observation, the cell movement range in high glucose+negative control siRNA group was smaller than that in normal glucose+negative control siRNA group, while the cell movement range in normal glucose+P62-siRNA group was larger than that in normal glucose+negative control siRNA group, and the cell movement range in high glucose+P62-siRNA group was larger than that in high glucose+negative control siRNA group. Compared with that in normal glucose+negative control siRNA group, the cell trajectory speed in normal glucose+P62-siRNA group was significantly increased (P<0.01), while the cell trajectory speed in high glucose+negative control siRNA group was significantly decreased (P<0.01); compared with that in high glucose+negative control siRNA group, the cell trajectory speed in high glucose+P62-siRNA group was significantly increased (P<0.01). At 48 h of culture, compared with that in normal glucose+PBS group, the protein expression of P62 of cells in high glucose+PBS group was significantly increased (P<0.01); compared with that in high glucose+PBS group, the protein expression of P62 of cells in high glucose+NAC group was significantly decreased (P<0.01). At 48 h of culture, the green fluorescence of P62 of cells in high glucose+PBS group was stronger than that in normal glucose+PBS group, while the green fluorescence of P62 of cells in high glucose+NAC group was weaker than that in high glucose+PBS group. Conclusions: In HaCaT cells, high glucose microenvironment can promote the protein expression of P62; knockdown of P62 protein can promote the migration and increase the mobility of HaCaT cells; and the increase of reactive oxygen species in high glucose microenvironment may be the underlying mechanism for the increase of P62 expression.

Genetic Variation in Schizothorax kozlovi Nikolsky in the Upper Reaches of the Chinese Yangtze River Based on Genotyping for Simplified Genome Sequencing

Simple Summary

Schizothorax kozlovi Nikolsky is a unique cold−water fish in the upper reaches of the Yangtze River in China and has high economic value. In our study, genetic diversity and population structure analyses were performed on seven wild populations in the upper reaches of the Yangtze River by GBS. The above results indicate that the populations of S. kozlovi have different degrees of tolerance and selection pressure in response to temperature and altitude. The Wujiang population was genetically differentiated from the Jinsha River and Yalong River populations. The Wujiang intrapopulation has greater genetic diversity and differentiation than the Jinsha River and Yalong River populations, which demonstrates that the Jinsha and Yalong populations require more attention and resources for their protection. The results of this study will increase our understanding of the diversity of S. kozlovi in the upper reaches of the Yangtze River and provide a basis for the conservation and utilization of wild resources.

Abstract

Schizothorax kozlovi Nikolsky is a unique cold−water fish in the upper reaches of the Yangtze River in China and has high economic value. In our study, genetic diversity and population structure analyses were performed on seven wild populations (originating from the Jinsha River, Yalong River, and Wujiang River) in the upper reaches of the Yangtze River by genotyping by sequencing (GBS). The results indicated that a total of 303,970 single−nucleotide polymorphisms (SNPs) were identified from the seven wild populations. Lower genetic diversity was exhibited among the intrapopulations of the three tributaries, and the Wujiang River population had significant genetic differentiation when compared to the Jinsha River and Yalong River populations. Furthermore, the selected SNPs were enriched in cellular processes, environmental adaptation, signal transduction, and related metabolic processes between the Wujiang population and the other two populations. The above results indicate that the populations of S. kozlovi have different degrees of tolerance and selection pressure in response to temperature and altitude. The Wujiang intrapopulation has greater genetic diversity and differentiation than the Jinsha River and Yalong River populations, which demonstrates that the Jinsha and Yalong populations require more attention and resources for their protection. The results of this study will increase our understanding of the diversity of S. kozlovi in the upper reaches of the Yangtze River and provide a basis for the conservation and utilization of wild resources.

Circular RNA expression profiles and CircSnd1-miR-135b/c-foxl2 axis analysis in gonadal differentiation of protogynous hermaphroditic ricefield eel Monopterus albus

BACKGROUND

The expression and biological functions of circular RNAs (circRNAs) in reproductive organs have been extensively reported. However, it is still unclear whether circRNAs are involved in sex change. To this end, RNA sequencing (RNA-seq) was performed in gonads at 5 sexual stages (ovary, early intersexual stage gonad, middle intersexual stage gonad, late intersexual stage gonad, and testis) of ricefield eel, and the expression profiles and potential functions of circRNAs were studied.

RESULTS

Seven hundred twenty-one circRNAs were identified, and the expression levels of 10 circRNAs were verified by quantitative real-time PCR (qRT-PCR) and found to be in accordance with the RNA-seq data, suggesting that the RNA-seq data were reliable. Then, the sequence length, category, sequence composition and the relationship between the parent genes of the circRNAs were explored. A total of 147 circRNAs were differentially expressed in the sex change process, and GO and KEGG analyses revealed that some differentially expressed (such as novel_circ_0000659, novel_circ_0004005 and novel_circ_0005865) circRNAs were closely involved in sex change. Furthermore, expression pattern analysis demonstrated that both circSnd1 and foxl2 were downregulated in the process of sex change, which was contrary to mal-miR-135b. Finally, dual-luciferase reporter assay and RNA immunoprecipitation showed that circSnd1 and foxl2 can combine with mal-miR-135b and mal-miR-135c. These data revealed that circSnd1 regulates foxl2 expression in the sex change of ricefield eel by acting as a sponge of mal-miR-135b/c.

CONCLUSION

Our results are the first to demonstrate that circRNAs have potential effects on sex change in ricefield eel; and circSnd1 could regulate foxl2 expression in the sex change of ricefield eel by acting as a sponge of mal-miR-135b/c. These data will be useful for enhancing our understanding of sequential hermaphroditism and sex change in ricefield eel or other teleosts.

Identification, characterization and functional analysis of gonadal long noncoding RNAs in a protogynous hermaphroditic teleost fish, the ricefield eel (Monopterus albus)

Background

An increasing number of long noncoding RNAs (lncRNAs) have been found to play important roles in sex differentiation and gonad development by regulating gene expression at the epigenetic, transcriptional and posttranscriptional levels. The ricefield eel, Monopterus albus, is a protogynous hermaphroditic fish that undergoes a sequential sex change from female to male. However, the roles of lncRNA in the sex change is unclear.

Results

Herein, we performed RNA sequencing to analyse lncRNA expression patterns in five different stages of M. albus development to investigate the roles of lncRNAs in the sex change process. A total of 12,746 lncRNAs (1503 known lncRNAs and 11,243 new lncRNAs) and 2901 differentially expressed lncRNAs (DE-lncRNAs) were identified in the gonads. The target genes of the DE-lncRNAs included foxo1, foxm1, smad3, foxr1, camk4, ar and tgfb3, which were mainly enriched in signalling pathways related to gonadal development, such as the insulin signalling pathway, MAPK signalling pathway, and calcium signalling pathway. We selected 5 highly expressed DE-lncRNAs (LOC109952131, LOC109953466, LOC109954337, LOC109954360 and LOC109958454) for full length amplification and expression pattern verification. They were all expressed at higher levels in ovaries and intersex gonads than in testes, and exhibited specific time-dependent expression in ovarian tissue incubated with follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG). The results of quantitative real-time PCR (qRT-PCR) analysis and a dual-luciferase assay showed that znf207, as the gene targeted by LOC109958454, was expressed in multiple tissues and gonadal developmental stages of M. albus, and its expression was also inhibited by the hormones FSH and hCG.

Conclusions

These results provide new insights into the role of lncRNAs in gonad development, especially regarding natural sex changes in fish, which will be useful for enhancing our understanding of sequential hermaphroditism and sex changes in the ricefield eel (M. albus) and other teleosts.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08679-2.

[Prokaryotic expression and purification of nucleoprotein of Guertu virus and its establishment of ELISA detection method]

Objective: To obtain purified protein antigen of guertu virus (GTV) nucleoprotein (NP) and establish a rapid and accurate enzyme-linked immunosorbent assay (ELISA) method for detection of GTV antibody. Methods: Codon optimized GTV NP encoding genes were synthesized, cloned into the pet32a (+) vector, and recombinant expression plasmids were constructed and transformed into BL21 (DE3). Recombinant protein (rNP) obtained from the optimized expression were purified over a Ni column and identified by SDS-PAGE and Western blot. The purified protein was used as the antigen to optimize the reaction conditions, and an indirect ELISA assay for GTV IgG antibody was developed and optimized, which was evaluated and initially applied. Results: The prokaryotic expression plasmid pet32a-NP was successfully constructed, the recombinant protein was highly expressed in E. coli in the form of inclusion bodies, the size was about 44 kD, and the results of Western blot indicated that the recombinant protein had good antigenicity with GTV positive serum. The optimized ELISA (GTV-rNP-iELISA) established in this study showed strong specificity, high sensitivity, and the coefficient of variation within and between batches is less than 10%, and has good repeatability; the detection results are consistent with the IFA detection results. Using the established ELISA method to detect 162 sheep sera from some regions of Xinjiang in 2017-2019, the total positive rate of antibodies was 39.8%. Conclusions: The GTV NP antibody detection ELISA method has good sensitivity, reproducibility, and specificity and has the potential to be a powerful tool for the diagnosis and serological investigation of GTV infection.

Molecular characterization, expression, and apoptosis regulation of siva1 in protogynous hermaphrodite fish ricefield eel (Monopterus albus)

Siva1, which induces extensive apoptosis, has been well characterized. To elucidate the molecular function of Siva1 in ricefield eel, molecular characterization and phylogenetic analysis were performed, and the mRNA expression in the ovary at different developmental stages and ovary tissues exposed to H₂O₂ and Z-VAD-FMK in vitro were also evaluated. The results indicated that ricefield eel Siva1 was highly conserved and contains three conserved motifs, despite 83 amino acid differences upstream of the initiation codon. Phylogenetic analysis demonstrated that ricefield eel Siva1 clusters together with the Siva1 protein of the other fish, with high sequence homology with that of Lates calcarifer. Quantitative real-time polymerase chain reaction analysis showed high siva1 expression levels in the ovary and low expression levels in the liver. The higher mRNA levels of siva1 were detected in the IE and IM, and the lower siva1 mRNA levels were found in the OM, IL, and TE during gonadal development. Additionally, siva1 expression levels in the ovarian tissues were significantly increased at 1 h post incubation (hpi) with H₂O₂ and then significantly decreased at 2 hpi; however, siva1 expression was upregulated significantly at 4 and 8 hpi, similar to the patterns observed with caspase3, which was used as a molecular marker of apoptosis. Moreover, the siva1 mRNAs were elevated significantly than that in control groups at 1 hpi, but the expression of siva1 was down-regulated dramatically at 2, 4, and 8 hpi, which were similar with that of caspase3 expression profiles after Z-VAD-FMK incubation. What's more, Pearson's correlation coefficients showed strongly positive relationships between siva1 and caspase3. These findings suggest that Siva1 plays an important apoptosis role in gonadal development of ricefield eel.

Diagnostic Performance of Conebeam CT Pixel Values in Active Fenestral Otosclerosis

BACKGROUND AND PURPOSE

Quantitative bone densitometry on multidetector CT of the temporal bone is a diagnostic adjunct for otosclerosis in its active (spongiotic) phase, but translating this technique to conebeam CT is limited by the technical variability of conebeam CT pixel values. The purpose of this study was to evaluate the performance of internally calibrated conebeam CT pixel value measurements that can enable the determination of active fenestral otosclerosis (otospongiosis).

MATERIALS AND METHODS

This study included 37 ears in 22 patients with a clinical diagnosis of otospongiosis in those ears and 35 ears in 22 control patients without the diagnosis. Temporal bone conebeam CT was performed. ROIs were set anterior to the oval window, in the lateral semicircular canal bone island, and in a nearby aerated space. Mean conebeam CT pixel values in these regions determined the relative attenuation ratio of the area anterior to the oval window normalized to normal otic capsule bone and air.

RESULTS

The relative attenuation ratio for cases of otospongiosis was significantly lower than that for controls (P < .001). Based on receiver operating characteristic analysis, the optimal cutoff relative attenuation ratio was 0.876, which had an accuracy of 97.2% for the diagnosis of otospongiosis.

CONCLUSIONS

Internally calibrated pixel value ratios in temporal bone conebeam CT can feasibly help diagnose active/spongiotic-phase fenestral otosclerosis in an objective manner.

Analysis of Stroke Detection during the COVID-19 Pandemic Using Natural Language Processing of Radiology Reports

BACKGROUND AND PURPOSE

The coronavirus disease 2019 (COVID-19) pandemic has led to decreases in neuroimaging volume. Our aim was to quantify the change in acute or subacute ischemic strokes detected on CT or MR imaging during the pandemic using natural language processing of radiology reports.

MATERIALS AND METHODS

We retrospectively analyzed 32,555 radiology reports from brain CTs and MRIs from a comprehensive stroke center, performed from March 1 to April 30 each year from 2017 to 2020, involving 20,414 unique patients. To detect acute or subacute ischemic stroke in free-text reports, we trained a random forest natural language processing classifier using 1987 randomly sampled radiology reports with manual annotation. Natural language processing classifier generalizability was evaluated using 1974 imaging reports from an external dataset.

RESULTS

The natural language processing classifier achieved a 5-fold cross-validation classification accuracy of 0.97 and an F1 score of 0.74, with a slight underestimation (-5%) of actual numbers of acute or subacute ischemic strokes in cross-validation. Importantly, cross-validation performance stratified by year was similar. Applying the classifier to the complete study cohort, we found an estimated 24% decrease in patients with acute or subacute ischemic strokes reported on CT or MR imaging from March to April 2020 compared with the average from those months in 2017-2019. Among patients with stroke-related order indications, the estimated proportion who underwent neuroimaging with acute or subacute ischemic stroke detection significantly increased from 16% during 2017-2019 to 21% in 2020 (P = .01). The natural language processing classifier performed worse on external data.

CONCLUSIONS

Acute or subacute ischemic stroke cases detected by neuroimaging decreased during the COVID-19 pandemic, though a higher proportion of studies ordered for stroke were positive for acute or subacute ischemic strokes. Natural language processing approaches can help automatically track acute or subacute ischemic stroke numbers for epidemiologic studies, though local classifier training is important due to radiologist reporting style differences.

MicroRNA-378 inhibits the development of smoking-induced COPD by targeting TNF-α

OBJECTIVE

To explore the mechanism microRNA-378 in smoking-induced airway inflammation and mucus hypersecretion.

MATERIALS AND METHODS

Human bronchial epithelial (HBE) cells were treated with cigarette smoke extract (CSE) to construct the in vitro COPD model. Expression levels of microRNA-378, inflammatory factors and MUC5AC in CSE-treated HBE cells were determined by quantitative real-time polymerase chain reaction (qRT-PCR), Western blot and enzyme-linked immunosorbent assay (ELISA). The regulatory effects of microRNA-378 on expressions of inflammatory factors and mucin 5AC (MUC5AC) were observed in CSE-treated HBE cells overexpressing microRNA-378. We verified whether tumor necrosis factor-α (TNF-α) was the target gene of microRNA-378 through dual-luciferase reporter gene assay. Expression levels of TNF-α and p-p65 in CSE-treated HBE cells were examined. Finally, CSE-treated HBE cells were co-overexpressed with microRNA-378 and TNF-α to elucidate whether microRNA-378 exerted its function in regulating the development of COPD through targeting TNF-α.

RESULTS

CSE treatment downregulated microRNA-378 expression, but upregulated expressions of inflammatory factors and MUC5AC in HBE cells. MicroRNA-378 overexpression markedly inhibited the elevated levels of inflammatory factors and MUC5AC in CSE-treated HBE cells. Dual-luciferase reporter gene assay verified that TNF-α was the target gene of microRNA-378. Moreover, TNF-α expression in CSE-treated HBE cells was time-dependently elevated. TNF-α overexpression partially reversed the decreased levels of inflammatory factors and MUC5AC in HBE cells overexpressing microRNA-378.

CONCLUSIONS

MicroRNA-378 inhibits the inflammatory response by targeting TNF-α, which may be a potential therapeutic target for COPD.

MiR-373 promotes proliferation and metastasis of oral squamous cell carcinoma by targeting SPOP

OBJECTIVE

To explore the biological function of microRNA-373 (miR-373) in regulating the progression of oral squamous cell carcinoma (OSCC) and the related mechanism.

PATIENTS AND METHODS

50 patients who were diagnosed as OSCC in the Department of Stomatology of the Stomatological Hospital of Chongqing Medical University were enrolled as the cancer group. 20 healthy oral mucosa specimens were obtained as the control group. The miR-373 level in both OSCC clinical samples and cell lines was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The binding relationship between speckle-type POZ protein (SPOP) and miR-373 was detected through online prediction software and luciferase reporter assay.

RESULTS

MiR-373 was upregulated in OSCC samples and cell lines. It could negatively regulate the protein expression of SPOP. However, it did not affect the mRNA expression of SPOP. The up-regulation of miR-373 promoted proliferation, invasion, and migration ability of the OSCC cells. However, the effects of miR-373 were abolished by the over-expression of SPOP in cells.

CONCLUSIONS

Up-regulated miR-373 promotes proliferation, invasion, and migration of OSCC by targeting SPOP. MiR-373/SPOP axis could be a potential therapeutic target for OSCC.

Expression patterns and oestradiol regulation of growth differentiation factor 9 in Schizothorax prenanti

Growth differentiation factor 9 (GDF9) plays pivotal roles in regulating follicular development in many mammalian species. In the present study, the full-length Schizothorax prenanti gdf9 cDNA sequence was isolated and characterized, and its expression pattern in developing gonads and in the gonads of exogenous oestradiol (E₂)-fed fish were analysed. The S. prenanti gdf9 cDNA sequence consisted of 1958 base pairs (bp), encoded a 413 amino acid, and showed high sequence similarity with Carassius gibelio and Cyprinus carpio. The quantitative real-time PCR analysis revealed that gdf9 was mainly expressed in the gonads, with particularly high expression in the cortical alveoli stage ovary and late-spermatogenic stage testis. Immunohistochemical signals for Gdf9 were mainly detected in chromatin nucleolar oocytes, spermatogonia and spermatocytes. Furthermore, the gonadal expression of gdf9 induced by exogenous E₂ was related to the feeding time and dose. Taken together, these findings were helpful to gain a better understanding of the role of Gdf9 in both folliculogenesis and spermatogenesis in S. prenanti.

Expression and regulation of Smad2 by gonadotropins in the protogynous hermaphroditic ricefield eel (Monopterus albus)

Smad2, a receptor-activated Smad, plays a critical role in regulating gametogenesis. In this study, a smad2 homologue was identified and sequenced from ricefield eel ovary cDNA, and its mRNA and protein expression levels were analysed during oocyte development. The cDNA sequence of ricefield eel smad2 consisted of 1863 bp encoding a 467-amino acid protein that had high sequence homology with Smad proteins in other teleosts, especially in Poeciliopsis prolifica. The results of real-time quantitative PCR (RT-qPCR) analysis revealed that smad2 is expressed in the ovary during gonad development, increased continuously until the early vitellogenic stage in the ovaries, and then decreased with ovary maturation. Smad2 protein immunoreactivity was localized in the cytoplasm of follicular cells, oogonia, and primary growth stage oocytes. In vitro experiments revealed that follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG) promoted smad2 expression in ovary tissue in a time- and dose-dependent manner, respectively. In summary, Smad2 plays a potentially vital role in ricefield eel ovary development.

[Adverse maternal and infant health effects caused by thallium exposure during pregnancy]

Thallium is a highly toxic heavy metal. The adverse maternal and infant health effects caused by thallium exposure during pregnancy have also attracted more and more scholars' attention. This study focused on the sources of thallium exposure and its influencing factors, the association between thallium exposure during pregnancy and pregnancy complications and adverse birth outcomes in newborns, the effects of thallium exposure during pregnancy on children's growth and development after birth. In terms of potential mechanisms, the related research progress was reviewed in this study, which could provide a new basis for further research on the harm, prevention and control of thallium exposure during pregnancy.

Cardiovascular benefits of reducing personal exposure to traffic-related noise and particulate air pollution: A randomized crossover study in the Beijing subway system

To assess the cardiovascular benefits of protecting against particulate air pollution and noise, we conducted a randomized crossover study with 40 young healthy college students from March to May 2017 in the underground subway, Beijing. Participants each received 4 treatments (no intervention phase [NIP], respirator intervention phase [RIP], headphone intervention phase [HIP], respirator plus headphone intervention phase [RHIP]) in a randomized order during 4 different study periods with 2-week washout intervals. We measured personal exposure to particulate matter (PM), noise and electrocardiogram (ECG) parameters (heart rate variability (HRV), heart rate (HR) and ST segment changes), ambulatory blood pressure (BP) continuously for 4 hours to investigate the cardiovascular effects. Compared with NIP, most of the HRV parameters increased, especially high frequency (HF) [21.1% (95% CI: 15.7%, 26.9%), 18.2% (95% CI: 12.8%, 23.9%), and 35.5% (95% CI: 29.3%, 42.0%) in RIP, HIP, and RHIP, respectively], whereas ST segment elevation and HR decreased for all 3 modes of interventions. However, no significant differences were observed in BP among the 4 treatments. In summary, short-term wearing of a respirator and/or headphone may be an effective way to minimize cardiovascular risk induced by air pollution in the subway by improving autonomic nervous function.

Association of size-fractionated indoor particulate matter and black carbon with heart rate variability in healthy elderly women in Beijing

Associations between size-fractionated indoor particulate matter (PM) and black carbon (BC) and heart rate variability (HRV) and heart rate (HR) in elderly women remain unclear. Twenty-nine healthy elderly women were measured for 24-hour HRV/HR indices. Real-time size-fractionated indoor PM and BC were monitored on the same day and on the preceding day. Mixed-effects models were applied to investigate the associations between pollutants and HRV/HR indices. Increases in size-fractionated indoor PM were significantly associated with declines in power in the high-frequency band (HF), power in the low-frequency band (LF), and standard deviation of all NN intervals (SDNN). The largest decline in HF was 19% at 5-minute moving average for an interquartile range (IQR) increase (24 μg/m³ ) in PM_0.5 . The results showed that smaller particles could lead to greater reductions in HRV indices. The reported associations were modified by body mass index (BMI): Declines in HF at 5-minute average for an IQR increase in PM_0.5 were 34.5% and 1.0% for overweight (BMI ≥25 kg/m² ) and normal-weight (BMI <25 kg/m² ) participants, respectively. Moreover, negative associations between BC and HRV indices were found to be significant in overweight participants. Increases in size-fractionated indoor PM and BC were associated with compromised cardiac autonomic function in healthy elderly women, especially overweight ones.

[The value of serum human tumor protein P53 in colorectal cancer combined diagnosis and postoperative monitoring]

Objective: The aim of this paper is to investigate the application value of serum human tumor protein P53 (TP53) in the diagnosis and postoperative monitoring of colorectal cancer. Methods: One hundred and fifteen patients with colorectal cancer diagnosed without colorectal cancer and without surgery, radiotherapy and chemotherapy and total of 158 patients with colorectal benign disease and 182 healthy subjects were enrolled in this study. The levels of serum carcinoembryonic antigen (CEA) and carbohydrate antigen 199 (CA199) were detected by electrochemiluminescence assay. The expression of TP53 was analyzed by ELISA. Fourth-one patients with colorectal cancer were detected with one day before operation and the first seven days after operation. The expression of CEA, CA199 and TP53 was analyzed by ROC curve. The results were compared with those of CEA and CA199 diagnostic value. Results: The medians of the levels of TP53 in patients with colorectal cancer patients, colorectal benign, and healthy subjects are 316.0(24.6, 940.8 ) , 9.8(3.7, 30.1 ) and 1.9(1.4, 2.5 ) μg/L (H=260.161, P<0.01), respectively. The level of TP53 in patients with colorectal cancer was significantly higher than that in colorectal benign and healthy subjects. The levels of serum TP53 in patients with colorectal cancer show great discrepancies in different TNM stages, different tumor location, depth of invasion and lymph node metastasis (P<0.05) , but no difference in sex, age, and tumor growth type. The levels of TP53 in the same patient is 711.5(354.9, 1 068.0) μg/L in the first seven days after operation, significantly decreased when compared to it in the one day before the operation with the value of 952.6 (419.7, 1485.4) μg/L (Z=-1.989, P<0.05). The difference was statistically significant, and CEA, CA199 were not statistically significant. And the sensitivity (79.1%) and specificity (81.8%) of TP 53 were significantly higher than those of CEA (39.1%, 70.3%) and CA199 (47.8%, 69.1%). If TP53 was combined with CEA and CA199, sensitivity (86.1%) and specificity (87.9%) can be significantly improved, in which the area of Receiver Operating Characteristic (ROC) curve was 0.924. Conclusions: Serum TP53 has a certain positive significance for the diagnosis, postoperative monitoring of colorectal cancer. Combined detection with CEA and CA199 can improve the sensitivity and specificity, implicating good clinical application value.

The role of Notch1 genes in lung cancer A594 cells and the impact on chemosensitivity

OBJECTIVE

Expression of Notch1 gene in lung cancer A549 cells was reduced using small interfering RNA (small interfering RNA, siRNA) and the effect of Notch1 gene on proliferation and chemo sensitivity of lung cancer A549 cells was studied.

MATERIALS AND METHODS

The Notch1 siRNA was transfected into A549 cells by liposome to inhibit the expressions of Notch1 gene in A549 cells. Real-time polymerase chain reaction (RT-PCR) and Western blot were used to detect the expression of Notch1 gene and protein. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method was used to detect the proliferation of A549 cells. After transfection of Notch1-siRNA, cisplatin was added to each group at a concentration of 4 μg/ml, and cultured for 48 h. MTT assay and 4',6-diamidino-2-phenylindole (DAPI) staining was used to evaluate the change of apoptosis and sensitivity to chemotherapy.

RESULTS

Notch1 gene expression of A594 cells, detected by RT-PCR and Western blot was significantly reduced in transfected cells when compared with the control group (p<0.05). Inhibition of A594 cell proliferation was significantly decreased as detected by MTT (p<0.05), and the MTT assay and DAPI staining showed that Notch1 gene silencing can significantly improve the sensitivity of A549 cells to chemotherapeutic drugs.

CONCLUSIONS

The Notch1 siRNA can effectively inhibit the expression of Notch1 gene, inhibit the proliferation of lung cancer A549 cells and increase the sensitivity to chemotherapeutic drugs.

Expanding public health in China: an empirical analysis of healthcare inputs and outputs

OBJECTIVES

The Chinese Government claims that China's health policy is primarily focused on prevention. However, this does not appear to be the case. Researchers with an interest in China's health policy may be aware that the Chinese Government launched a health reform in 2009 to improve the health status of the entire population by 2020.¹ This health reform has been in place for 7 years, and only 4 years now remain to achieve the overall objectives by 2020. This study analyzed the main inputs and outputs of China's health reform in order to identify the main problems and highlight the major challenges. It is hoped that this study will provide some reference for health reform in China and other developing countries.

STUDY DESIGN

This study focused on health, with human resources and healthcare costs as the main input indicators, and 2-week prevalence of illness and prevalence of non-communicable diseases as the main output indicators. By longitudinal comparison of real data from 2009 to 2014, the effects of China's health reform were analyzed to identify the main challenges, enabling suggestions to be made for future reference.

METHODS

This was a retrospective analysis of empirical data. Data were collected between 2009 and 2014 as follows: (1) data on the distribution of healthcare professionals were collected from the Statistical Bulletin of China's Health Development, issued by the National Health and Family Planning Commission every year between 2009 and 2014; (2) data on government health expenditure were obtained from the Annual National Public Fiscal Expenditure Data, released by the Financial Ministry of the People's Republic of China from 2009 to 2014; (3) data on the prevalence of chronic diseases, 2-week prevalence of illness, residents' medical service demands, and utilization of health services were obtained from the Fourth and Fifth National Health Care Surveys in 2008 and 2013; and (4) data on total healthcare expenditure, medical expenditure and out-of-pocket payments were obtained from the 2015 China Statistical Yearbook.

RESULTS

From 2009 to 2014, China's healthcare human resources were distributed primarily in hospitals that focus on providing treatment. By 2014, 62.5% of the health professionals and technical personnel were distributed in hospitals. From 2009, the Chinese Government spent more money on health care than previously, with approximately 67% spent on disease treatment and 14.19% spent on disease prevention. However, the 2-week prevalence of illness increased by 5.2 percentage points, and the prevalence of chronic diseases increased by 9 percentage points. Meanwhile, residents' out-of-pocket payments for health care were as high as 50.61% of the total healthcare expenditure and were particularly high in rural areas.

CONCLUSION

China should adjust the direction of its health reform as soon as possible to focus on improving health status rather than treatment of disease. In the future, as China's population ageing trend intensifies, China must take effective measures or the country's non-communicable disease rates will continue to increase. To meet this challenge, China's health reform should take effective measures to control the rising trend of the incidence of non-communicable diseases. First, China should focus on the core goal of its health reform policy, which is disease prevention. Second, China should focus on strengthening public health systems to effectively prevent and control key epidemic diseases. Third, China should increase the number of public health personnel, improve the level of education and training of public health personnel and increase the input of funds into the field of public health as soon as possible.

Subclinical hypothyroidism and the associations with macrovascular complications and chronic kidney disease in patients with Type 2 diabetes

AIMS

The prevalence of subclinical hypothyroidism (SCH) is high among patients with diabetes, although the relationship between SCH and diabetic vascular complications is unknown. This study aimed to determine the relationship between SCH and vascular complications in patients with Type 2 diabetes.

METHODS

In this cross sectional study, 991 patients with Type 2 diabetes were screened for thyroid function at their admission to the Second Affiliated Hospital of Chongqing Medical University. We compared the prevalence of coronary heart disease (CHD), ischaemic stroke and chronic kidney disease (CKD) with the prevalence of euthyroidism and SCH.

RESULTS

Among the 991 patients, 126 (12.7%) patients had SCH. The prevalence of CHD was significantly higher in the SCH group than in the euthyroid group (22.2% and 15.0%, respectively; P = 0.039). In the logistic regression analyses, SCH was associated with CHD [odds ratio (OR): 1.993; 95% confidence interval (CI): 1.135-3.497; P = 0.016]. This association was stronger in patients aged ≥ 65 years than in younger patients [2.474 (1.173-5.220); P = 0.017]. No significant association was found between SCH and ischaemic stroke. Patients with severe SCH had a high risk of CKD [1.842 (1.120-3.029); P = 0.016].

CONCLUSIONS

This study provides evidence that SCH in patients with Type 2 diabetes is associated with a high prevalence of CHD (and CKD in severe SCH), although not with ischaemic stroke.

The DYX2 locus and neurochemical signaling genes contribute to speech sound disorder and related neurocognitive domains

A major milestone of child development is the acquisition and use of speech and language. Communication disorders, including speech sound disorder (SSD), can impair a child's academic, social and behavioral development. Speech sound disorder is a complex, polygenic trait with a substantial genetic component. However, specific genes that contribute to SSD remain largely unknown. To identify associated genes, we assessed the association of the DYX2 dyslexia risk locus and markers in neurochemical signaling genes (e.g., nicotinic and dopaminergic) with SSD and related endophenotypes. We first performed separate primary associations in two independent samples - Cleveland SSD (210 affected and 257 unaffected individuals in 127 families) and Denver SSD (113 affected individuals and 106 unaffected individuals in 85 families) - and then combined results by meta-analysis. DYX2 markers, specifically those in the 3' untranslated region of DCDC2 (P = 1.43 × 10(-4) ), showed the strongest associations with phonological awareness. We also observed suggestive associations of dopaminergic-related genes ANKK1 (P = 1.02 × 10(-2) ) and DRD2 (P = 9.22 × 10(-3) ) and nicotinic-related genes CHRNA3 (P = 2.51 × 10(-3) ) and BDNF (P = 8.14 × 10(-3) ) with case-control status and articulation. Our results further implicate variation in putative regulatory regions in the DYX2 locus, particularly in DCDC2, influencing language and cognitive traits. The results also support previous studies implicating variation in dopaminergic and nicotinic neural signaling influencing human communication and cognitive development. Our findings expand the literature showing genetic factors (e.g., DYX2) contributing to multiple related, yet distinct neurocognitive domains (e.g., dyslexia, language impairment, and SSD). How these factors interactively yield different neurocognitive and language-related outcomes remains to be elucidated.

Photochemical upconversion and triplet annihilation limit from a boron dipyrromethene emitter

Non-coherent sensitized red-to-green upconversion has been achieved utilizing platinum(ii) tetraphenyltetrabenzoporphyrin (PtTPTBP) as the triplet sensitizer and a nearly quantitatively fluorescent boron dipyrromethene chromophore as the energy acceptor/annihilator in deoxygenated toluene.

Overexpression of Ad5 precursor terminal protein accelerates recombinant adenovirus packaging and amplification in HEK-293 packaging cells

Recombinant adenoviruses are one of the most common vehicles for efficient in vitro and in vivo gene deliveries. Here, we investigate whether exogenous precursor terminal protein (pTP) expression in 293 cells improves the efficiency of adenovirus packaging and amplification. We used a piggyBac transposon-based vector and engineered a stable 293 line that expresses high level of Ad5 pTP, designated as 293pTP. Using the AdBMP6-GLuc that expresses green fluorescent protein (GFP), BMP6 and Gaussia luciferase, we found that the infectivity of AdBMP6-GLuc viral samples packaged in 293pTP cells was titrated up to 19.3 times higher than that packaged in parental 293 cells. AdBMP6-GLuc viral samples packaged in 293pTP cells exhibited significantly higher transduction efficiency in 143B and immortalized mouse embryonic fibroblast (iMEF) cells, as assessed by fluorescence-activated cell sorting analysis of GFP-positive cells, the luciferase activity assay and BMP6-induced osteogenic marker alkaline phosphatase activities in iMEFs. When adenovirus amplification efficiency was analyzed, we found that 293pTP cells infected with AdBMP6-GLuc yielded up to 12.6 times higher titer than that in parental 293 cells, especially at lower multiplicities of infection. These results strongly suggest that exogenous pTP expression may accelerate the packaging and amplification of recombinant adenoviruses. Thus, the engineered 293pTP cells should be a superior packaging line for efficient adenovirus production.

Comparison of dexmedetomidine/fentanyl with midazolam/fentanyl combination for sedation and analgesia during tooth extraction

Dexmedetomidine is an α2-adrenergic receptor agonist that causes minimal respiratory depression compared with alternative drugs. This study investigated whether combined dexmedetomidine/fentanyl offered better sedation and analgesia than midazolam/fentanyl in dental surgery. Sixty patients scheduled for unilateral impacted tooth extraction were randomly assigned to receive either dexmedetomidine and fentanyl (D/F) or midazolam and fentanyl (M/F). Recorded variables were patient preoperative anxiety scores, vital signs, visual analogue scale (VAS) pain scores, Observer's Assessment of Alertness/Sedation Scale (OAAS) scores after drug administration, surgeon and patient degree of satisfaction, and the duration of analgesia after surgery. The OAAS scores were significantly lower for patients administered D/F compared to those who received M/F. The duration of analgesia after the surgical procedure was significantly longer in patients who received D/F (5.3 h) than in those who received M/F (4.1 h; P=0.017). The number of surgeons satisfied with the level of sedation/analgesia provided by D/F was significantly higher than for M/F (P=0.001). Therefore, dexmedetomidine/fentanyl appears to provide better sedation, stable haemodynamics, surgeon satisfaction, and postoperative analgesia than midazolam/fentanyl during office-based unilateral impacted tooth extraction.

Identifying significant crosstalk of pathways in tuberous sclerosis complex

OBJECTIVE

Tuberous sclerosis complex (TSC) is the second most common phakomatosis and is characterized by the formation of benign hamartomas and low-grade neoplasms in multiple organ systems. In this study, our objective here was to explore the interaction and crosstalk between pathways in response to tuberous sclerosis complex.

MATERIALS AND METHODS

We enriched the significant pathways and made the crosstalk analysis of the significant pathways.

RESULTS

The results showed that ECM-receptor interaction was a significant pathway in TSC. In addition, insulin-signaling and mTOR signaling also have been identified involved in TSC here, which have been well characterized. Further analysis indicated that there was a crosstalk between ECM-receptor interaction and antigen processing and presentation, ECM-receptor interaction and apoptosis, and leishmaniasis-oxidative phosphorylation-pancreatic cancer. In this study, a network-based approach was used to analyze the crosstalk among TSC related pathways. The crosstalk of pathways is found and analyzed using the PPI datasets and expression profiles.

CONCLUSIONS

Our work showed that comprehensive and system-wide analysis could provide evidence for TSC pathway and complement the traditional component-based approaches. The crosstalk identified might provide new alternative insights into the TSC pathology, which may contribute to the development of novel therapeutic targets for TSC.

The Synthesis and Properties of High Pure δ Layered Sodium Disilicate

δ layered sodium disilicate (δ-Na2Si2O5) is a single layer silicate and has good properties as detergent builder. However, it is difficult to synthesize high pure δ-Na2Si2O5. In this paper, a feasible and simple technology was found by decreasing Na content in liquid sodium silicate (water glass). The crystalline time was short and no seed needed. The suitable synthesis conditions were Si/Na = 1.05–1.10, calcining at 720 °C for 5 minutes. The synthesis conditions are of industrial value. XRD and 29Si NMR data proved that synthesized samples were δ-Na2Si2O5 without impure phase. High pure δ-Na2Si2O5 exhibited good ions binding ability and reached 312 to 338 mg CaCO3/g.

Synthesis and Properties of Al-δ Layered Sodium Disilicate with High Framework Stability

Al-δ layered sodium disilicate with high framework stability in hot water (60–80°C) has been successfully synthesized from the system of Na2O–Al2O3–SiO2–H2O. It was shown that the presence of aluminum can improve the purity of δ phase. After marinated in hot distilled water for 60minutes, Al-δ layered sodium disilicate still kept δ phase and had better Ca2+ binding capacity and calcium binding rate. This property of Al-δ layered sodium disilicate may extend its application field. The samples were characterized by XRD, FT-IR, MAS NMR, Ca2+ binding capacity and rate, The data of 27Al MAS NMR and 29Si MAS NMR showed that aluminum was incorporated essentially in tetrahedral framework position, and substitute for SiO4 tetrahedron in sheet of δ layered sodium disilicate.

Characterization of the carbonic anhydrases 15b expressed in PGCs during early zebrafish development

The main function of carbonic anhydrases is to regulate acid-base balance. In the present study, the zebrafish CA15b sequence was identified from the National Center for Biotechnology Information database (accession No. NM_213182). The 1716 base pair full-length cDNA of CA15b was obtained by 3' and 5'-rapid amplification of cDNA ends analysis. It was expressed (reverse transcription polymerase chain reaction and Western blot analysis) in the ovary, heart, brain, and muscle, but not in testis or liver. Based on in situ hybridization, CA15b mRNA was transcribed in the ooplasm of stage I to stage II oocytes, in the cortex of stage III oocytes, and along the periphery of stage IV oocytes. Furthermore, this protein was localized (immunohistochemistry) in the plasma membrane of oocytes. Based on whole-mount in situ hybridization, CA15b mRNA was present in every blastomere of embryos from one-cell to blastula stages. Strong signals of the transcripts were present along cleavage furrows of two- and eight-cell stage embryos, which subsequently condensed into four clusters of cells during the blastula stage. During subsequent stages, the four groups of CA15b-expressing cells appeared to move toward the dorsal side of the embryos, clustered into two groups on either side of the midline, and remained visible as they migrated toward the region of the gonad in embryos at 24 hours postfertilization. Expression patterns of CA15b were similar to those of vasa, a marker of primordial germ cells. Thus, we hypothesized that CA15b might be necessary for development of primordial germ cells and female germ cells in zebrafish.

Analysis of the structural proteins from the Musca domestica hytrosavirus with an emphasis on the major envelope protein

The Musca domestica hytrosavirus (MdHV), a member of the family Hyrosaviridae, is a large, dsDNA, enveloped virus that infects adult house flies and causes a diagnostic hypertrophy of the salivary gland. Herein, studies were directed at identifying key structural components of the viral envelope and nucleocapsid. SDS-PAGE of detergent-treated virus fractions identified protein bands unique to the envelope and nucleocapsid components. Using prior LC-MSMS data we identified the viral ORF associated with the major envelope band, cloned and expressed recombinant viral antigens, and prepared a series of polyclonal sera. Western blots confirmed that antibodies recognized the target viral antigen and provided evidence that the viral protein MdHV96 underwent post-translational processing; antibodies bound to the target high molecular weight parent molecule as well as distinct sets of smaller bands. Immuno gold electron microscopy demonstrated that the anti-MdHV96 sera recognized target antigens associated with the envelope. The nucleocapsids migrated from the virogenic stroma in the nucleus through the nuclear membrane into the cytoplasm, where they acquired an initial envelope that contained MdHV96. This major envelope protein, appeared to incorporate into intracellular membranes of both the caniculi and rough endoplasmic reticulum membranes and mediate binding to the nucleocapsids. Oral infection bioassays demonstrated that the anti-HV96 polyclonal sera acted as neutralizing agents in suppressing the levels of orally acquired infections.

Double-quantum homonuclear NMR correlation spectroscopy of quadrupolar nuclei subjected to magic-angle spinning and high magnetic field

We present a new application of the R2(2)(1) symmetry-based dipolar recoupling scheme, for exciting directly double-quantum (2Q) coherences between the central transition of homonuclear half-integer quadrupolar nuclei. With respect to previously published 2Q-recoupling methods (M. Eden, D. Zhou, J. Yu, Chem. Phys. Lett. 431 (2006) 397), the R2(2)(1) sequence is used without pi/2 bracketing pulses and with an original super-cycling. This leads to an improved efficiency (a factor of two for spin-5/2) and to a much higher robustness to radio-frequency field inhomogeneity and resonance offset. The 2Q-coherence excitation performances are demonstrated experimentally by (27)Al NMR experiments on the aluminophosphates berlinite, VPI5, AlPO(4)-14, and AlPO(4)-CJ3. The two-dimensional 2Q-1Q correlation experiments incorporating these recoupling sequences allow the observation of 2Q cross-peaks between central transitions, even at high magnetic field where the difference in offset between octahedral and tetrahedral (27)Al sites exceeds 10 kHz.

Robust and efficient spin-locked symmetry-based double-quantum homonuclear dipolar recoupling for probing (1)H-(1)H proximity in the solid-state

We report a novel symmetry-based method, using inversion elements bracketed by spin locks, for exciting double-quantum (DQ) coherences between spin-1/2 nuclei, such as protons. Compared to previous DQ-recoupling techniques, this new pulse sequence requires moderate rf field, even at ultra-fast MAS speeds. Furthermore, it is easy to implement and it displays higher robustness to both chemical shift anisotropy and to spreads in resonance frequencies. These advances greatly facilitate the observation of (1)H-(1)H proximities at high fields and high MAS frequencies.

Cloning and characterization of a novel oocyte-specific gene zorg in zebrafish

Genes specifically expressed in oocytes are important for the development of both germ cells and embryos. Using the digital differential display program from the NCBI, we identified a novel EST sequence (no. DT881820) from zebrafish ovary libraries in the GenBank. The full-length cDNA of this transcript was obtained by performing 3'- and 5'-RACE and was confirmed by PCR and direct sequencing methods. The cDNA clone for this novel gene consisted of 894 base pairs and encoded a protein with 215 amino acids. Since this protein shared no significant homology with any other known proteins, we have named this gene zorg (zebrafish oogenesis related gene). Based on RT-PCR analysis, this gene was specially expressed in the ovary and was abundantly present at the blastula stage. However, the level of expression decreased significantly during the early gastrula periods. Based on whole-mount in situ hybridization studies, zorg transcripts were uniformly distributed in the cleavage stage through to the blastula stage. In addition, during early gastrulation, zorg transcripts appeared in the dorsal region, but became restricted to the primordial germ cells (PGC) in early somitogenesis and remained visible in PGC as they migrated towards the region of the gonad of embryos 24h post-fertilization. In situ hybridization of sectioned ovaries demonstrated that zorg mRNAs appeared in the cytoplasm of stage I and stage II oocytes and localized in the cortex of stage III and stage IV oocytes during oogenesis. We hypothesized that the protein expressed from the zebrafish zorg gene has roles in the formation of the female germ cells and in early embryonic development in zebrafish.

Manual versus electric vacuum aspiration for first-trimester abortion: a systematic review

BACKGROUND

As an alternative to electric vacuum aspirations (EVA), there is an increasing interest in using manual vacuum aspiration (MVA).

OBJECTIVE

To compare the safety, efficacy and acceptability of MVA with those of EVA for first-trimester abortion.

SEARCH STRATEGY

We searched MEDLINE, EMBASE, Cochrane Library and Chinese Biomedical Database in all language, together with reference lists of retrieved papers.

SELECTION CRITERIA

Randomised controlled trials comparing MVA with EVA for first-trimester abortion were included. The outcomes are complete abortion rate, uterine perforation rate, blood loss, pain perception and acceptability.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted the data. Results from the trials were combined to calculate relative risks (RRs) or risk differences for dichotomous outcomes and weighted mean differences (WMDs) for continuous outcomes, together with 95% CIs.

MAIN RESULTS

Ten trials were included, involving 1660 women. Generally, the methodological quality was poor. There were no statistically significant differences, comparing MVA with EVA, in complete abortion rate (RR 1.00; 95% CI 0.99-1.02) and participants' satisfaction (RR 1.02; 95% CI 0.87-1.20). In participants with less than 50 days of gestational age, less blood loss (WMD -1.84; 95% CI -2.45 to -1.23) and less severe pain perception (RR 0.04; 95% CI 0.01-0.12) were reported during the MVA procedure, whereas the operation time was shorter (WMD 0.32; 95% CI 0.02-0.63) in the EVA procedure.

AUTHOR'S CONCLUSIONS

There is some evidence that MVA is as effective and acceptable as EVA and might be safer than EVA.

Inhibition of reverse transcriptase activity of hepatitis B virus polymerase by β-l-D4A-TP

β-L-enantiomer of 2',3'-didehydro-2',3'-dideoxyadenosine-5'-triphosphate (β-L-D4A-TP) has previously been proven to inhibit the replication of viral DNA in the Hep G2 2.2.15 cells and in transgenic mouse harboring 1.3-fold-overlength genome of Hepatitis B virus (HBV). To study the inhibition mechanism of the nucleoside analog β-L-D4A-TP, a polymerase reaction in vitro with the recombinant HBV nucleocapsids was conducted to determine the exact mode of inhibition of the HBV replication by β-L-D4A-TP. The HBV viral DNA and viral DNA-polymerase complex formed in the polymerase reaction were assayed. The results of this study showed that β-L-D4A-TP inhibited the replication of HBV DNA by inactivating the reverse transcriptase (RT) activity in a concentration-dependent manner. The kinetics of β-L-D4A-TP inhibition of the RT activity was the result of an apparent competitive inhibition with dATP.

LAI inversion algorithm based on directional reflectance kernels

Leaf area index (LAI) is an important ecological and environmental parameter. A new LAI algorithm is developed using the principles of ground LAI measurements based on canopy gap fraction. First, the relationship between LAI and gap fraction at various zenith angles is derived from the definition of LAI. Then, the directional gap fraction is acquired from a remote sensing bidirectional reflectance distribution function (BRDF) product. This acquisition is obtained by using a kernel driven model and a large-scale directional gap fraction algorithm. The algorithm has been applied to estimate a LAI distribution in China in mid-July 2002. The ground data acquired from two field experiments in Changbai Mountain and Qilian Mountain were used to validate the algorithm. To resolve the scale discrepancy between high resolution ground observations and low resolution remote sensing data, two TM images with a resolution approaching the size of ground plots were used to relate the coarse resolution LAI map to ground measurements. First, an empirical relationship between the measured LAI and a vegetation index was established. Next, a high resolution LAI map was generated using the relationship. The LAI value of a low resolution pixel was calculated from the area-weighted sum of high resolution LAIs composing the low resolution pixel. The results of this comparison showed that the inversion algorithm has an accuracy of 82%. Factors that may influence the accuracy are also discussed in this paper.