[Application of next-generation sequencing technology in prenatal screening and diagnosis]

Developed rapidly for more than ten years, next-generation sequencing (NGS) has derived a series of new technologies which are widely used clinically, such as noninvasive prenatal testing(NIPT), noninvasive prenatal testing-plus(NIPT Plus), copy number variation sequencing(CNV-seq), and exome sequencing(ES), and plays an important role in birth defects prevention. Moreover, with in-deep development, the superiority of NGS is gradually recognized by clinicians, but there are still many challenges in practical application process. This study specifically elaborates on the development status, technological breakthroughs and future prospects of NGS in the field of prenatal screening and prenatal diagnosis at home and abroad.

[Polarization of bone marrow-derived macrophages induced by recombinant Trichinella spiralis cysteine protease inhibitors in vitro]

OBJECTIVE

To investigate the regulatory role of recombinant Trichinella spiralis cysteine protease inhibitors (rTs-Cys) in induction of polarization of bone marrow-derived macrophages (BMDMs) in vitro.

METHODS

BMDMs were captured and cultured in conditioned medium for 7 days. Then, mature BMDMs were harvested and assigned into four groups. Cells in Group A (negative control) were given 10 ng/mL IFN-γ combined with 100 ng/mL LPS, cells in Group B (positive control) were treated with IL-4 and IL-10 (at 10 ng/mL both), and cells in Group C (recombinant protein alone) were stimulated with 1 μg/mL rTs-Cys, while cells in Group D (protein co-culture) were simultaneously treated with 1 μg/mL rTs-Cys, 10 ng/mL IFN-γ and 100 ng/mL LPS. Cells and culture supernatant were collected 24 hour post-treatment, and the proportions of F4/80⁺, CD11b⁺, CD206⁺ and CD11c⁺ cells were detected by flow cytometry. The levels of interleukin IL-6 (IL-6), tumor necrosis factor-α (TNF-α), IL-10 and transforming growth factor-β (TGF-β) in the cell culture supernatant were measured by ELISA and the CD86⁺ and CD206⁺ phenotypes were identified by immunofluorescent staining.

RESULTS

Flow cytometry detected no significant difference in the proportion of F4/80⁺ CD11b⁺ CD11c⁺ cells among the four groups (F = 46.184, P < 0.001), and a lower proportion of F4/80⁺ CD11b⁺ CD11c⁺ cells was seen in groups C and D than in group A (all P values < 0.001). There was a significant difference in the proportion of F4/80⁺ CD11b⁺ CD206⁺ cells among the four groups (F = 11.032, P < 0.001), and a greater proportion of F4/80⁺ CD11b⁺ CD206⁺ cells was seen in groups C and D than in group A (all P values < 0.01). Immunofluorescent staining showed higher CD206⁺ expression and lower CD86⁺ expression in groups C and D than in Group A. There were significant differences in the IL-6 and (F = 3.950, P < 0.001) and TNF-α (F = 205.827, P < 0.001) levels in the cell culture supernatants among the four groups, and significantly lower IL-6 and TNF-α levels were measured in groups C and D than in Group A (both P < 0.05). There were significant differences in the IL-10 and (F = 8.274, P < 0.001) and TGF-β (F = 13.559, P < 0.01) levels in the cell culture supernatants among the four groups, and greater IL-10 and TGF-β levels were measured in Group C than in Group A (both P values < 0.01). In addition, the TGF-β level was significantly higher in Group D than in Group A (P < 0.05); however, there was no significant difference in the IL-10 level between groups D and A (P > 0.05).

CONCLUSIONS

rTs-Cys may induce the polarization of BMDMs to antiinflammatory M2 macrophages in vitro and inhibit the activation of M1 macrophages.

[Expression of RAGE in asthmatic rats and the intervention of Roxithromycin]

Objective: To observe the expression of the Receptor of Advanced glycation end products (RAGE) in asthmatic rats, and explore the intervention of Roxithromycin. Methods: A total of 18 Specific Pathogen Free-class Brown Norway male rats were randomly divided into control group, asthma model group and Roxithromycin group, with 6 rats in each group. The asthmatic model was sensitized by intraperitoneal injection of Ovalbumin (OVA)+Al(OH)(3), and challenged with OVA. Rats in Roxithromycin group were given Roxithromycin 30 mg/kg 30 minutes before each challenge. Rats in control group and asthma model group were treated with equal volume of saline. The concentrations of RAGE and interleukin (IL)-4 in serum and bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent (ELISA); the pathological changes of lung tissues were observed by HE-staining; the thickness of airway wall and airway smooth muscle were measured by Image-Pro Plus; the relative expression of RAGE in lung tissues were detected by Western blot. Results: In asthma model group, the concentrations of RAGE and IL-4 in the serum and BALF were obviously higher than those in control group [(494±32) vs (327±45) ng/L; (32.4±5.8) vs (13.1±2.9) ng/L; (553±38) vs (399±56) ng/L; (37.8±3.4) vs (19.4±2.5) ng/L] (all P<0.01); in Roxithromycin group, the concentrations of RAGE and IL-4 in the serum and BALF were obviously lower than those in asthma model group [(438±18) vs (494±32) ng/L; (22.8±6.0) vs (32.4±5.8) ng/L; (444±42) vs (553±38) ng/L; (25.6±4.5) vs (37.8±3.4) ng/L] (all P<0.05). In asthma model group, the bronchial wall was thickened, the lumen was narrow, the mucosal wrinkles were significantly increased, edema appeared under the mucosa, and a large number of inflammatory cells infiltrated and aggregated in the bronchi, perivascular and alveolar spaces; the thickness of airway wall and airway smooth muscle were significantly increased than those in control group (P<0.01); in Roxithromycin group, airway inflammation and remodeling were alleviated compared with those in asthma model group (P<0.05). In asthma model group, the expression of RAGE in lung tissues were significantly increased than those in control group (P<0.01); in Roxithromycin group, the expression of RAGE were significantly decreased than those in asthma model group (P<0.01). There were positive correlations between the expression of RAGE and IL-4 in BALF and serum (r=0.782, 0.804, all P<0.01); there were positive correlations between RAGE and total white cell counts, eosinophil counts, smooth muscle thickness (r=0.897, 0.927, 0.860, all P<0.01). Conclusions: The increasing of RAGE in asthmatic rats are positively correlated with airway inflammation and airway remodeling. Roxithromycin may inhibit the development of asthma by reducing the expression of RAGE.

A genome for gnetophytes and early evolution of seed plants

Gnetophytes are an enigmatic gymnosperm lineage comprising three genera, Gnetum, Welwitschia and Ephedra, which are morphologically distinct from all other seed plants. Their distinctiveness has triggered much debate as to their origin, evolution and phylogenetic placement among seed plants. To increase our understanding of the evolution of gnetophytes, and their relation to other seed plants, we report here a high-quality draft genome sequence for Gnetum montanum, the first for any gnetophyte. By using a novel genome assembly strategy to deal with high levels of heterozygosity, we assembled >4 Gb of sequence encoding 27,491 protein-coding genes. Comparative analysis of the G. montanum genome with other gymnosperm genomes unveiled some remarkable and distinctive genomic features, such as a diverse assemblage of retrotransposons with evidence for elevated frequencies of elimination rather than accumulation, considerable differences in intron architecture, including both length distribution and proportions of (retro) transposon elements, and distinctive patterns of proliferation of functional protein domains. Furthermore, a few gene families showed Gnetum-specific copy number expansions (for example, cellulose synthase) or contractions (for example, Late Embryogenesis Abundant protein), which could be connected with Gnetum's distinctive morphological innovations associated with their adaptation to warm, mesic environments. Overall, the G. montanum genome enables a better resolution of ancestral genomic features within seed plants, and the identification of genomic characters that distinguish Gnetum from other gymnosperms.

[Clinicopathologic features of hepatocellular carcinoma patients surviving more than 10 years after radical hepatectomy]

Objective: To clarify the clinicopathologic features of hepatocellular carcinoma (HCC) patients survived more than 10 years after radical hepatectomy. Methods: Two hundreds and fifty-two patients who underwent curative resection for HCC between January 1999 and March 2006 at Department of Hepatopancreatobiliary Surgery, Affiliated Hospital of Qingdao University were included.There were 217 male cases and 35 female cases aging from 17 to 82 years with median age of (53.8±10.5)years. Followed by March 31 2016, clinicopathologic factors in 10-year survivors and patients who died within 10 years were compared by χ(2) test, Kaplan-Meier survival analysis and Cox proportional hazards model and the prognostic factors affecting survival were identified. Results: All patients were followed-up for 4.0 to 205.7 months with median time of 53.4 months. The 10-year overall survival rate was 26%, there were 62 cases(26.2%) who survived for more than 10 years after initial hepatectomy. In survival >10-year group, the paitents with ALT<40 U/L, gamma-glutamyl transpeptidase<64 U/L, albumin≥35 g/L, without liver cirrhosis and portal hypertension, Child-Pugh grade A, no blood transfusion, AFP≤20 μg/L, tumor size ≤5.0 cm, single tumor, high differentiation, TNM stage Ⅰ and TACE negative after resection were more than the patients in survival <10-year group (P<0.05). In multivariate analysis, Child-Pugh grade A, the tumor size ≤5.0 cm and TACE negative after resection were favorable independent factors associated with 10-year survival (P<0.05). Conclusion: Based on the results of the study, Child-Pugh grade A, tumor size ≤5.0 cm and TACE negative after resection at initial hepatectomy might be biologically favorable conditions for patients surviving more than 10 years.

MicroRNA-92b promotes hepatocellular carcinoma progression by targeting Smad7 and is mediated by long non-coding RNA XIST

MicroRNA (miRNA) and long non-coding RNA (lncRNA) have been demonstrated to participate in the progression of many cancers. Hepatocellular carcinoma (HCC) is one of the most common and aggressive malignant tumors worldwide, while the molecular mechanisms underlying HCC tumorigenesis are not completely clear. In this study, we showed that miR-92b was significantly upregulated in tumor tissue and plasma of HCC patients, and its expression level was highly correlated with gender and microvascular invasion. Functionally, miR-92b could promote cell proliferation and metastasis of HCC in vitro and in vivo. Mechanistic investigations suggested that Smad7, which exhibited an inverse relationship with miR-92b expression in HCC, was a direct target of miR-92b and could reverse its effects on HCC tumorigenesis. Furthermore, long non-coding RNA (lncRNA) X-inactive specific transcript (XIST) and miR-92b could directly interact with and repress each other, and XIST could inhibit HCC cell proliferation and metastasis by targeting miR-92b. Taken together, our study not only revealed for the first time the importance of XIST/miR-92b/Smad7 signaling axis in HCC progression but also suggested the potential value of miR-92b as a biomarker in the clinical diagnosis and treatment of HCC.

[Tissue heterogeneity analysis of CGG-repeat mutation in two fragile X affected male fetuses]

OBJECTIVE

To compare the CGG-repeat-length and its methylation status in fetal tissues and to explicate the heterogeneity of CGG repeats.

METHOD

Multiple tissues from a full mutation(August 2013) and a mosaic aborted fetus of 23-week gestation(May 2012) were collected and genomic DNA from these tissues was extracted. The CGG-repeat-length and methylation status in fetal tissues were determined by a combined strategy of Southern blotting and GC-Rich PCR. FMR1 expression was measured by real time PCR and Western blotting.

RESULT

CGG-repeat-length in different tissues of each fetus was similar.A major methylated band in the full mutation range (540 CGG repeats) was detected in the brain, skin, testis and kidney tissues of Case 1. An unmethylated premutation band with 160 CGG repeats, and another two bands with 470 and 1 100 CGG repeats in the full mutation range were shown in the brain, skin, testis, lung, stomach, gut, liver, kidney, heart and blood of Case 2. However, the methylation status of CGG repeats in the mosaic fetus was heterogeneous among different tissues. The lowest premutation ratio was in the brain of the mosaic fetus compared with other tissues, and correspondingly FMR1 expression in its brain was minimum.

CONCLUSION

This study clarify the tissue heterogeneity of CGG repeats and provides information for the genetic counseling and clinical diagnosis in fragile X syndrome. Based on the fact that the mosaic fetus' mother is a carrier of full mutation, it is speculated that the maternal CGG repeat has contracted before the differentiation of trilaminar germ disc.

Antisense expression of Gossypium hirsutum UDP-glucuronate decarboxylase in Arabidopsis leads to changes in cell wall components

UDP-glucuronate decarboxylase (UDP-xylose synthase; UXS, EC 4.1.1.35) is an essential enzyme of the non-cellulosic polysaccharide biosynthetic pathway. In the present study, using transient expression of fluorescently labeled Gossypium hirsutum UXS (GhUXS3) protein in onion epidermal cells, we observed that this protein was distributed in the cytoplasm. The GhUXS3 cDNA of cotton was expressed in an antisense orientation in Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation. Homozygous plants showing down-regulation of UXS were analyzed with northern blots. Compared to the untransformed control, transgenic plant showed shorter roots, earlier blossom formation, and delayed senescence. Biochemical analysis indicated that levels of rhamnose, mannose, galactose, glucose, xylose, and cellulose were reduced in some of the down-regulated antisense plants. These results suggest that GhUXS3 regulates the conversion of non-cellulosic polysaccharides and modulates their composition in plant cell walls. We also discuss a possible cellular function for GhUXS in determining the quality of cotton fibers.

Identification of a novel mutation of the EDA gene in X-linked hypohidrotic ectodermal dysplasia

This study aimed to identify the disease-causing mutation in the ectodysplasin A (EDA) gene in a Chinese family affected by X-linked hypohidrotic ectodermal dysplasia (XLHED). A family clinically diagnosed with XLHED was investigated. For mutation analysis, the coding region of EDA of 2 patients and 7 unaffected members of the family was sequenced. The detected mutation in EDA was investigated in 120 normal controls. A missense mutation (c.878T>G) in EDA was detected in 2 patients and 3 female carriers, but not in 4 unaffected members of the family. The mutation was not found in the 120 healthy controls and has not been reported previously. Our findings indicate that a novel mutation (c.878T>G) of EDA is associated with XLHED and adds to the repertoire of EDA mutations.

-173G/C polymorphism in the promoter of MIF is associated with hepatitis B virus infection in a Chinese Han population

In addition to the host immune response, genetic and environmental factors play crucial roles in the manifestation of hepatitis B virus (HBV) infection. The macrophage migration inhibitory factor (MIF) -173G/C polymorphism (rs755622), located in the promoter region of MIF, may play integral roles in diverse processes, including the immune response. Thus, the MIF -173G/C polymorphism may influence the immune response to HBV during natural infection. We investigated whether the MIF -173G/C polymorphism was associated with susceptibility to HBV infection in a Chinese Han population. A total of 596 HBV infection cases and 612 age-matched controls were recruited for the study. Genotyping of the MIF -173G/C polymorphism was performed using the allele-specific polymerase chain reaction method. The frequencies of the alleles and genotypes in patients and controls were compared using the χ(2) test. Carriers of the variant C allele in MIF -173 G/C were at significantly higher risk of HBV infection than carriers of the wild-type allele (P = 0.032, odds ratio = 0.799, 95% confidence interval = 0.651-0.981). However, there was no significant difference in the distribution of MIF -173G/C genotypes between case and control groups in either population (P = 0.096, degrees of freedom = 2). Our findings indicate that the G to C base change in MIF -173 G/C confers an increased risk of development of HBV infection by altering the expression of MIF in our Chinese Han population.

Two novel NPHS1 mutations in a Chinese family with congenital nephrotic syndrome

Congenital nephrotic syndrome of the Finnish type (CNF) is a lethal, autosomal recessive disorder mainly caused by mutations in the NPHS1 gene; it is found at a relatively high frequency in Finns. We investigated the disease-causing mutations in a Chinese family with CNF and developed a prenatal genetic diagnosis for their latest pregnancy. Mutation analysis was made of all exons and exon/intron boundaries of NPHS1 in the fetus, parents and 50 unrelated controls using PCR and direct sequencing. A heterozygous nonsense mutation within exon 20 (c.2783C>A) and a missense mutation within exon 17 (c.2225T>C) in NPHS1 were detected in the proband's father and mother, respectively, but were not found in the fetus or in 50 unrelated controls. Two novel mutations of c.2783C>A and c.2225T>C in NPHS1 were found to be causative in this Chinese CNF family with no known Finnish ancestry. The most recent sibling did not inherit these two mutations and hence was unaffected with CNF. Determining the cumulative number and ethnic distribution of known mutations can help expedite further study of the pathogenesis of CNF.

New technique for mouse oocyte injection via a modified holding pipette

To improve mouse oocyte survival from intracytoplasmic sperm injection, the sharp tip of the injection pipette has been modified to have a flat end. Here, for the same goal but for a more convenient manipulation, a sharp injection pipette was kept whereas the holding pipette was modified to have a trumpet-shaped opening, which allows deeper injection into the oocyte as it is held. Mouse oocyte injection with mouse and human spermatozoa was performed at 37°C. For the injection of mouse oocyte with mouse sperm head, a significantly higher survival rate (83%) was achieved by utilizing the modified holding pipette than the conventional one (21%; P<0.001) and the fertilization rates were normal and comparable for both methods (82% versus 81%). A superior survival rate (82%) and acceptable normal fertilization rate (71%) were also achieved by utilizing the modified holding pipette for interspecies ICSI (injecting mouse oocyte with human spermatozoon). Taken together, by utilizing a holding pipette with a trumpet-shaped opening, acceptable rates of mouse oocyte survival and fertilization can be achieved using a sharp injection pipette under conditions usual for human oocyte injection.

Mutation L437P in the 2B domain of keratin 1 causes diffuse palmoplantar keratoderma in a Chinese pedigree

Diffuse palmoplantar keratoderma (DPPK) is an autosomal dominant genodermatosis characterized by uniform hyperkeratosis of the palm and sole epidermis. This disorder can be caused by mutations in the genes keratin 1, keratin 9, keratin 16, desmoglein 1 and plakoglobin. Here we present a DPPK Chinese pedigree and identify the aetiology as a novel missense mutation, L437P, located in a highly conserved helix motif in domain 2B of KRT1. Functional analysis shows that overexpression of the L437P mutant in cultured cells leads to abnormal intermediate filament networks and filament aggregation. This gain-of-function mutation highlights the role of domain 2B in mediating filament assembly.

Graft-versus-host disease after liver transplantation: successful treatment of a case

Graft-versus-host disease (GVHD) is a rare, serious complication after liver transplantation. The incidence is about 1% abroad, but because of difficulties in diagnosis and treatment, the mortality rate is high (80%). Up to now, 78 patients have been reported to have this complication after liver transplantation worldwide; despite various therapeutic programs, the mortality of GVHD after orthotopic liver transplantation (OLT) is still high. Herein we have reported successful treatment of a case of GVHD after liver transplantation.

Transglutaminase crosslinked gelatin as a tissue engineering scaffold

Gelatin is one of the most commonly used biomaterials for creating cellular scaffolds due to its innocuous nature. In order to create stable gelatin hydrogels at physiological temperatures (37 degrees C), chemical crosslinking agents such as glutaraldehyde are typically used. To circumvent potential problems with residual amounts of these crosslinkers in vivo and create scaffolds that are both physiologically robust and biocompatible, a microbial transglutaminase (mTG) was used in this study to enzymatically crosslink gelatin solutions. HEK293 cells encapsulated in mTG-crosslinked gelatin proliferated at a rate of 0.03 day(-1). When released via proteolytic degradation with trypsin, the cells were able to recolonize tissue culture flasks, suggesting that cells for therapeutic purposes could be delivered in vivo using an mTG-crosslinked gelatin construct. Upon submersion in a saline solution at 37 degrees C, the mTG-crosslinked gelatin exhibited no mass loss, within experimental error, indicating that the material is thermally stable. The proteolytic degradation rate of mTG-crosslinked gelatin at RT was slightly faster than that of thermally-cooled (physically-crosslinked) gelatin. Thermally-cooled gelatin that was subsequently crosslinked with mTG resulted in hydrogels that were more resistant to proteolysis. Degradation rates were found to be tunable with gelatin content, an attribute that may be useful for either long-time cell encapsulation or time-released regenerative cell delivery. Further investigation showed that proteolytic degradation was controlled by surface erosion.

Transglutaminase crosslinked gelatin as a tissue engineering scaffold

Gelatin is one of the most commonly used biomaterials for creating cellular scaffolds due to its innocuous nature. In order to create stable gelatin hydrogels at physiological temperatures (37 degrees C), chemical crosslinking agents such as glutaraldehyde are typically used. To circumvent potential problems with residual amounts of these crosslinkers in vivo and create scaffolds that are both physiologically robust and biocompatible, a microbial transglutaminase (mTG) was used in this study to enzymatically crosslink gelatin solutions. HEK293 cells encapsulated in mTG-crosslinked gelatin proliferated at a rate of 0.03 day(-1). When released via proteolytic degradation with trypsin, the cells were able to recolonize tissue culture flasks, suggesting that cells for therapeutic purposes could be delivered in vivo using an mTG-crosslinked gelatin construct. Upon submersion in a saline solution at 37 degrees C, the mTG-crosslinked gelatin exhibited no mass loss, within experimental error, indicating that the material is thermally stable. The proteolytic degradation rate of mTG-crosslinked gelatin at RT was slightly faster than that of thermally-cooled (physically-crosslinked) gelatin. Thermally-cooled gelatin that was subsequently crosslinked with mTG resulted in hydrogels that were more resistant to proteolysis. Degradation rates were found to be tunable with gelatin content, an attribute that may be useful for either long-time cell encapsulation or time-released regenerative cell delivery. Further investigation showed that proteolytic degradation was controlled by surface erosion.

An improved mechanical technique for assisted hatching

BACKGROUND

Varied clinical outcomes of assisted hatching (AH) have been reported. We attempt to investigate whether the size of the zona opening created by AH is adequate for blastocyst hatching, and, if not, set up a new method to improve it.

METHODS

A new AH technique, long zona dissection (LZD), was established, and experiments were performed to compare the effects of different sizes of zona opening on complete hatching of blastocysts in mouse and human embryos in vitro.

RESULTS

The LZD technique can create a long zona slit on early embryos, even blastocysts, with the slit size beyond two-thirds of zona diameter. Compared with three-dimensional partial zona dissection, LZD can significantly enhance the hatching speed and the rate of complete hatching of mouse blastocysts (93.9%). All (100%) human blastocysts completely hatched following LZD; however, when the slit size after AH was about two-fifths of zona diameter, more of the larger inner cell masses (ICM) became trapped by the zona opening during hatching than the smaller ICM (53.3 versus 12.5%, P = 0.01).

CONCLUSIONS

Zona opening of moderate size following AH is inadequate for the completion of blastocyst hatching in vitro; in some cases, however, it can be significantly improved by LZD.

Confirmation and refinement of a genetic locus for disseminated superficial actinic porokeratosis (DSAP1) at 12q23.2-24.1

BACKGROUND

Our previous study has identified two loci for disseminated superficial actinic porokeratosis (DSAP), but the genes responsible are still unknown.

OBJECTIVES

To narrow down the candidate regions and to assess candidate genes.

METHODS

A genome-wide scan and linkage analysis were carried out in a newly collected five-generation Chinese family with DSAP. In addition, six candidate genes were screened for possible DSAP-associated mutations.

RESULTS

DSAP in this family was associated with chromosome 12q. Fine mapping and haplotype construction refined the DSAP1 locus to a 4.4-cM interval. No disease-associated mutation was detected in CRY1, C4ST1, TXNRD1, HCF2, CMKLR1 or KIAA0789 genes.

CONCLUSIONS

The DSAP1 locus was localized to a 4.4-cM interval at chromosome 12q23.2-24.1. CRY1, C4ST1, TXNRD1, HCF2, CMKLR1 and KIAA0789 genes were not associated with DSAP1.

Enzymatic coupling of phenol vapors onto chitosan

Phenols are important industrial chemicals, and because they can be volatile, also appear as air pollutants. We examined the potential of tyrosinase to react with the volatile phenol p-cresol. Three lines of evidence support the conclusion that volatile phenols react with tyrosinase and are coupled (i.e., chemisorbed) onto chitosan films. First, phenol-trapping studies indicated that p-cresol can be removed from vapors if the vapors are contacted with tyrosinase-coated chitosan films. Second, the ultraviolet absorbance of tyrosinase-coated chitosan films changes dramatically when they are contacted with cresol-containing vapors, whereas control films are unaffected by contacting with cresol vapors. Third, pressure measurements indicate that tyrosinase-coated chitosan films only react with cresol vapors if the oxygen cosubstrate is present. Additional studies demonstrate the potential of tyrosinase-coated chitosan films/membranes for the detection and removal of phenol vapors.