Subjective well-being amongst migrant children in China: unravelling the roles of social support and identity integration

BACKGROUND

Migrant children refer to rural children who accompany one or both parents to urban area. Empirical evidence showed that compared with their urban counterparts, migrant children had poorer developmental, emotional and psychological health.

METHOD

A sample of 1306 migrant children were recruited to examine the characteristics of migrant children and investigate the effects of identity integration, support and socioeconomic factors (e.g. age, gender, type of school, family socioeconomic status, city type) on their subjective wellbeing.

RESULTS

Children with higher levels of identity integration, social support, family socioeconomic status, who attended public school and who lived in the third-tiered city of Weihai demonstrated better subjective wellbeing. Social support remained a strong predictor for subjective wellbeing, despite a significant mediating effect of identity integration.

CONCLUSIONS

These results highlight the need for policymakers and practitioners alike to address individual factors pertaining to psychological adjustments, as well as social determinants of subjective wellbeing in the context of migration.

[Multi-disciplinary treatment increases the survival rate of late stage pharyngeal, laryngeal or cervical esophageal cancers treated by free jejunal flap reconstruction after cancer resection]

OBJECTIVE

To investigate the survival status of patients with pharyngeal, laryngeal or cervical esophageal cancers, who received free jejunal flap (FJF) to repair the defects following tumor resection, and to analyze the effect of multi-disciplinary treatment on their survival.

METHODS

Fifty-eight patients with pharyngeal, laryngeal or cervical esophageal cancer underwent free jejunal flap (FJF) reconstruction after cancer resection between 2010 and 2013. All their clinical records were reviewed and analyzed.

RESULTS

The success rate of flap transplantation was 91.4% (53/58). The 2-year overall survival rates (OSR) of cervical esophageal cancer and hypopharyngeal cancer patients were 67.5% and 49.3%, respectively, both were significantly better than that of laryngeal cancer. The main causes of death were local recurrence and distant metastases. The group with no short-term complications had a better two-year OSR (59.0%) than the group with short-term complications (46.6%), however, the difference between them was not significant (P=0.103). The 2-year survival rate of the initial treatment group was 65.0%, better than that of the salvage treatment group (49.4%), but the difference was not significant (P=0.051). For the stage III and IV patients, the multi-disciplinary treatment group had a significantly better 2-year OSR (64.7%) than the single or sequential treatment group (37.0%, P=0.016).

CONCLUSIONS

Free jejunal flap reconstruction is an ideal option for repairing the cervical digestive tract circumferential defects caused by tumor resection with a high success rate and a low mortality. Compared with the single or sequential treatment, multi-disciplinary treatment can significantly improve the survival rate of late-stage hypopharyngeal and cervical esophageal cancer patients.

Erythropoietin promotes bone formation through EphrinB2/EphB4 signaling

Recent studies have demonstrated that erythropoietin (EPO) has extensive nonhematopoietic biological functions. However, little is known about how EPO regulates bone formation, although several studies suggested that EPO can affect bone homeostasis. In this study, we investigated the effects of EPO on the communication between osteoclasts and osteoblasts through the ephrinB2/EphB4 signaling pathway. We found that EPO slightly promotes osteoblastic differentiation with the increased expression of EphB4 in ST2 cells. However, EPO increased the expression of Nfatc1 and ephrinB2 but decreased the expression of Mmp9 in RAW264.7 cells, resulting in an increase of ephrinB2-expressing osteoclasts and a decrease in resorption activity. The stimulation of ephrinB2/EphB4 signaling via ephrinB2-Fc significantly promoted EPO-mediated osteoblastic differentiation in ST2 cells. EphB4 knockdown through EphB4 shRNA inhibited EPO-mediated osteoblastic phenotypes. Furthermore, in vivo assays clearly demonstrated that EPO efficiently induces new bone formation in the alveolar bone regeneration model. Taken together, these results suggest that ephrinB2/EphB4 signaling may play an important role in EPO-mediated bone formation.

PCR screening reveals considerable unexploited biosynthetic potential of ansamycins and a mysterious family of AHBA-containing natural products in actinomycetes

AIMS

Ansamycins are a family of macrolactams that are synthesized by type I polyketide synthase (PKS) using 3-amino-5-hydroxybenzoic acid (AHBA) as the starter unit. Most members of the family have strong antimicrobial, antifungal, anticancer and/or antiviral activities. We aimed to discover new ansamycins and/or other AHBA-containing natural products from actinobacteria.

METHODS AND RESULTS

Through PCR screening of AHBA synthase gene, we identified 26 AHBA synthase gene-positive strains from 206 plant-associated actinomycetes (five positives) and 688 marine-derived actinomycetes (21 positives), representing a positive ratio of 2·4-3·1%. Twenty-five ansamycins, including eight new compounds, were isolated from six AHBA synthase gene-positive strains through TLC-guided fractionations followed by repeated column chromatography. To gain information about those potential ansamycin gene clusters whose products were unknown, seven strains with phylogenetically divergent AHBA synthase genes were subjected to fosmid library construction. Of the seven gene clusters we obtained, three show characteristics for typical ansamycin gene clusters, and other four, from Micromonospora spp., appear to lack the amide synthase gene, which is unusual for ansamycin biosynthesis. The gene composition of these four gene clusters suggests that they are involved in the biosynthesis of a new family of hybrid PK-NRP compounds containing AHBA substructure.

CONCLUSIONS

PCR screening of AHBA synthase is an efficient approach to discover novel ansamycins and other AHBA-containing natural products.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work demonstrates that the AHBA-based screening method is a useful approach for discovering novel ansamycins and other AHBA-containing natural products from new microbial resources.

Effects of 1.8 GHz radiofrequency radiation on protein expression in human lens epithelial cells

OBJECTIVE

The aim of the present study was to observe the effects of 1.8 GHz radiofrequency (RF) radiation on the protein expression of human lens epithelial cells (hLECs) in vitro.

METHODS

The hLECs were exposed and sham-exposed to 1.8 GHz RF radiation (specific absorption rate (SAR) of 4 W/kg) for 2 h. After exposure, the proteins extracted from LECs were loaded on the Ettan MDLC system connected to the LTQ-Orbitrap MS for screening the candidate protein biomarkers induced by RF. The quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the levels of messenger RNA of candidate biomarkers. After the hLECs were exposed to 1.8 GHz RF (SAR of 2, 3 and 4 W/kg) for 2 h, the Western blot assay was utilized to measure the expression levels of the above-screened candidate protein biomarkers.

RESULTS

The results of shotgun proteomic analysis indicated that there were eight proteins with differential expression between exposure and sham exposure groups. The results of qRT-PCR showed that there were three genes with expressional differences (valosin containing protein (VCP), ubiquitin specific peptidase 35 (USP35) and signal recognition particle 68 kDa (SRP68)) between exposure and sham exposure groups. The results of Western blot assay exhibited that the expressional levels of VCP and USP35 proteins significantly increased and the expressional level of protein SRP68 significantly decreased in hLECs exposed to 1.8 GHz RF radiation (SAR of 3 and 4 W/kg) for 2 h when compared with the corresponding sham groups (p < 0.05).

CONCLUSION

The shotgun proteomics technique can be applied to screen the proteins with differential expression between hLECs exposed to 1.8 GHz RF and hLECs sham-exposed to 1.8 GHz RF, and three protein biomarkers associated with RF radiation were validated by Western blot assay.

Perceived parenting and risk for major depression in Chinese women

BACKGROUND

In Western countries, a history of major depression (MD) is associated with reports of received parenting that is low in warmth and caring and high in control and authoritarianism. Does a similar pattern exist in women in China?

METHOD

Received parenting was assessed by a shortened version of the Parental Bonding Instrument (PBI) in two groups of Han Chinese women: 1970 clinically ascertained cases with recurrent MD and 2597 matched controls. MD was assessed at personal interview.

RESULTS

Factor analysis of the PBI revealed three factors for both mothers and fathers: warmth, protectiveness, and authoritarianism. Lower warmth and protectiveness and higher authoritarianism from both mother and father were significantly associated with risk for recurrent MD. Parental warmth was positively correlated with parental protectiveness and negatively correlated with parental authoritarianism. When examined together, paternal warmth was more strongly associated with lowered risk for MD than maternal warmth. Furthermore, paternal protectiveness was negatively and maternal protectiveness positively associated with risk for MD.

CONCLUSIONS

Although the structure of received parenting is very similar in China and Western countries, the association with MD is not. High parental protectiveness is generally pathogenic in Western countries but protective in China, especially when received from the father. Our results suggest that cultural factors impact on patterns of parenting and their association with MD.

Evaluation of adenovirus vectors containing serotype 35 fibers for tumor targeting

There is growing evidence from in vitro studies that subgroup B adenoviruses (Ad) can overcome the limitations in safety and tumor transduction efficiency seen with commonly used subgroup C serotype 5-based vectors. In this study, we confirm that the expression level of the B-group Ad receptor, CD46, correlates with the grade of malignancy of cervical cancer in situ. We also demonstrate the in vivo properties of Ad5-based vectors that contain the B-group Ad serotype 35 fiber (Ad5/35) in transgenic mice that express CD46 in a pattern and at a level similar to humans. Upon intravenous and intraperitoneal injection, an Ad5/35 vector did not efficiently transduce normal tissue, but was able to target metastatic or intraperitoneal tumors that express CD46 at levels comparable to human tumors. When an oncolytic Ad5/35-based vector was employed, in both tumor models antitumor effects were observed. Furthermore, injection of Ad5/35 vectors into CD46 transgenic mice caused less innate toxicity than Ad5 vectors. Our data demonstrate that Ad vectors that target CD46 offer advantages over Ad5-based vectors for treatment of cancer.

GRB2-mediated recruitment of GAB2, but not GAB1, to SF-STK supports the expansion of Friend virus-infected erythroid progenitor cells

Friend virus induces the development of erythroleukemia in mice through the interaction of a viral glycoprotein, gp55, with a truncated form of the Stk receptor tyrosine kinase, short form-Stk (Sf-Stk), and the EpoR. We have shown previously that the ability of Sf-Stk to participate in the transformation of Friend virus-infected cells requires the kinase activity and Grb2-binding site of Sf-Stk. Here we show that Grb2 heterozygous mice exhibit decreased susceptibility to Friend erythroleukemia and that expansion of erythroid progenitors in response to infection requires the C-terminal SH3 domain of Grb2. A fusion protein in which the Grb2-binding site in Sf-Stk is replaced by Gab2, supports the growth of progenitors from mice lacking Sf-Stk, whereas a Sf-Stk/Gab1 fusion protein does not. Gab2 is expressed in spleens from Friend virus-infected mice, co-immunoprecipitates with Sf-Stk and is tyrosine phosphorylated in the presence of Sf-Stk. Mice with a targeted deletion in Gab2 are less susceptible to Friend erythroleukemia and the expansion of erythroid progenitor cells in response to infection can be rescued by expression of Gab2, but not Gab1. Taken together, these data indicate that a Sf-Stk/Grb2/Gab2 complex mediates the growth of primary erythroid progenitor cells in response to Friend virus.

Deep mantle structure and the postperovskite phase transition

Seismologists have known for many years that the lowermost mantle of the Earth is complex. Models based on observed seismic phases sampling this region include relatively sharp horizontal discontinuities with strong zones of anisotropy, nearly vertical contrasts in structure, and small pockets of ultralow velocity zones (ULVZs). This diversity of structures is beginning to be understood in terms of geodynamics and mineral physics, with dense partial melts causing the ULVZs and a postperovskite solid-solid phase transition producing regional layering, with the possibility of large-scale variations in chemistry. This strong heterogeneity has significant implications on heat transport out of core, the evolution of the magnetic field, and magnetic field polarity reversals.

[The expression of BDNF and NT-3 in dorsal root ganglion following peripheral and central axotomy--an immunohistochemical study]

OBJECTIVE

To explore the expression of brain-derived neurotrophic factor (BDNF) and neurotrophin-3(NT-3) in dorsal root ganglion (DRG) following peripheral and central axotomy.

METHODS

Fifteen male adult cats were divided into intact group, peripheral axotomy group and central axotomy group. The ten cats of the latter two groups were subjected to unilateral peripheral cut and central processes cut respectively. The animals were allowed to survive 4 days long; L5 DRG was taken from each animal and made into frozen sections 20 microns thick. The sections were stained using antisera of BDNF and NT-3 respectively by immunohistchemical ABC method. The neuronal numbers of BDNF and NT-3 of the three groups were counted and compared.

RESULTS

The positive products of BDNF were mainly distributed in small to medium sized neurons (13-57 microns) while those of NT-3 were mainly in large sized neurons (57-100 microns). The neuronal numbers of BDNF and NT-3 in peripheral and central axotomy groups (24.1 +/- 3.5, 29.4 +/- 5.2; 19.4 +/- 2.4, 20.2 +/- 1.9) increased significantly than those of intact group (12.1 +/- 2.2, 13.3 +/- 2.9), P < 0.01. And the neuronal numbers of BDNF and NT-3 in peripheral axotomy groups were more than those of central axotomy group(P < 0.05).

CONCLUSION

The results indicate that peripheral axotomy and central axotomy lead to the increase of the expression of BDNF and NT-3 in DRG neurons. And the effect of peripheral axotomy is greater than that of central axotomy.

Loading estimates of lead, copper, cadmium, and zinc in urban runoff from specific sources

Urban stormwater runoff is being recognized as a substantial source of pollutants to receiving waters. A number of investigators have found significant levels of metals in runoff from urban areas, especially in highway runoff. As an initiatory study, this work estimates lead, copper, cadmium, and zinc loadings from various sources in a developed area utilizing information available in the literature, in conjunction with controlled experimental and sampling investigations. Specific sources examined include building siding and roofs; automobile brakes, tires, and oil leakage; and wet and dry atmospheric deposition. Important sources identified are building siding for all four metals, vehicle brake emissions for copper and tire wear for zinc. Atmospheric deposition is an important source for cadmium, copper, and lead. Loadings and source distributions depend on building and automobile density assumptions and the type of materials present in the area examined. Identified important sources are targeted for future comprehensive mechanistic studies. Improved information on the metal release and distributions from the specific sources, along with detailed characterization of watershed areas will allow refinements in the predictions.

Induced apoptosis supports spread of adenovirus vectors in tumors

Selectively replicating viruses hold promise as anticancer agents. To eliminate the tumor, these viruses must efficiently spread throughout the tumor and induce oncolysis. We hypothesized that viral release and spread could be supported by apoptosis induced after assembly of de novo-produced virions in tumor cells. As a model to test this, we employed an adenovirus vector that replicated in human tumor cell lines. Expression of a dominant-negative I-kappaB from this vector sensitized tumor cells to recombinant human tumor necrosis factor alpha (TNF-alpha)-mediated apoptosis. We found that apoptosis induced during viral DNA replication compromised virus production, whereas apoptosis induced after virion assembly enhanced viral release from infected cells and dissemination. Electron microscopy demonstrated that viral particles were associated with or included in apoptotic bodies whose phagocytosis by neighboring cells provides a potential means for viral spread. Apoptosis induced after viral replication also supported spread in vivo, in subcutaneous tumors or liver metastases, resulting in a delay of tumor growth. Our findings could be applicable to other selectively replicating viruses or antitumor strategies that involve application of proapoptotic or cytolytic agents.

Tumor-specific gene expression in hepatic metastases by a replication-activated adenovirus vector

Clinical applications of tumor gene therapy require tumor-specific delivery or expression of therapeutic genes in order to maximize the oncolytic index and minimize side effects. This study demonstrates activation of transgene expression exclusively in hepatic metastases after systemic application of a modified first-generation (E1A/E1B-deleted) adenovirus vector (AdE1-) in mouse tumor models. The discrimination between tumors and normal liver tissue is based on selective DNA replication of AdE1- vectors in tumor cells. This new AdE1- based vector system uses homologous recombination between inverted repeats to mediate precise rearrangements within the viral genome. As a result of these rearrangements, a promoter is brought into conjunction with a reporter gene creating a functional expression cassette. Genomic rearrangements are dependent upon viral DNA replication, which in turn occurs specifically in tumor cells. In a mouse tumor model with liver metastases derived from human tumor cells, a single systemic administration of replication activated AdE1- vectors achieved transgene expression in every metastasis, whereas no extra-tumoral transgene induction was observed. Here we provide a new concept for tumor-specific gene expression that is also applicable for other conditionally replicating adenovirus vectors.

[Synthesis and spectroscopic studies of new N-functionalized macrocyclic compounds and complex]

Three new N-functionalized tetraazamacrocyclic compounds, C-messo-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane- N,N',N",N'"-tetrakis (ethyl acetate) (A), C-messo-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetra- azacyclotetradecane-N,N,'N",N'"-tetraacetic acid (H4L) and the hydrobromide of H4L have been synthesized and the complex Na2[NiL].2C2H5OH has been prepared as well. The macroyclic compounds and the complex have been studied by electronic spectrum, infrared spectrum, 1H NMR, MS and elemental analysis.

Electrospray ionization-mass spectrometry study of the interaction of cisplatin-adducted oligonucleotides with human XPA minimal binding domain protein

Nucleotide excision repair (NER) is the process responsible for eliminating most ultraviolet (UV) radiation damage from DNA, as well as base alterations caused by a variety of mutagens. The xeroderma pigmentosum group A complementing protein (XPA) is believed to be involved in the early step of NER by recognizing and binding damaged DNA. Recent work has suggested that electrospray ionization-mass spectrometry (ESI-MS) can be an effective tool for the study of protein-DNA complexes. We have used ESI-Fourier transform ion cyclotron resonance (FTICR) mass spectrometry to examine the cisplatin-adducted oligonucleotide and its interaction with the human XPA minimal binding domain (XPA-MBD). High-resolution FTICR experiments of the binding products showed that both double-stranded damaged 20-mer and double-stranded undamaged 20-mer formed 1:1 noncovalent complexes with XPA-MBD. A 2:1 binding stoichiometry complex was also observed between XPA-MBD and double-stranded damaged 20-mer. Competitive binding experiments indicated only slightly preferential binding of XPA-MBD with the double-stranded damaged 20-mer compared to the undamaged 20-mer. The results demonstrate that ESI-FTICR mass spectrometry provides a fast and efficient approach for characterizing weak protein-DNA interactions such as the binding between XPA-MBD and a 20-mer oligonucleotide system.

[Applied anatomy of insular skin flap of nasolabial groove with retrograde superior labial artery]

In order to study the feasibiliy of the insular skin flap of the nasolabial groove with the retrograde superior labial artery, 8 adult cadavers were dissected and the relation between the superior labial artery and the skin of nasolabial groove was observed. The result revealed that superior labial artery was one of the branches of the facial artery and could be found in every cadaver. The diameter of the artery was 0.8 +/- 0.1 mm and the length was about 90 mm. The left and right facial arteries were connected with each other in the mid-line in the formation of the arcuate artery. The arcuate artery lay within the submucous tissue beyond the vermilion border about 6 mm. The concomitant veins were constant. If the facial artery being sectioned was beyond its initial site of superior labial artery, the skin of nasolabial groove on the same side could receive blood supply from contralateral supperior labial artery. The conclusion was that the insular skin flap of the nasolabial groove with the retrograde superior labial artery could be used in patients, because it had support from anatomical research.

Human nucleotide excision repair protein XPA: extended X-ray absorption fine-structure evidence for a metal-binding domain

The ubiquitous, multi-enzyme, nucleotide excision repair (NER) pathway is responsible for correcting a wide range of chemically and structurally distinct DNA lesions in the eukaryotic genome. Human XPA, a 31 kDa, zinc-associated protein, is thought to play a major NER role in the recognition of damaged DNA and the recruitment of other proteins, including RPA, ERCC1, and TFIIH, to repair the damage. Sequence analyses and genetic evidence suggest that zinc is associated with a C4-type motif, C105-X2-C108-X17-C126-X2-C129, located in the minimal DNA binding region of XPA (M98-F219). The zinc-associated motif is essential for damaged DNA recognition. Extended X-ray absorption fine structure (EXAFS) spectra collected on the zinc associated minimal DNA-binding domain of XPA (ZnXPA-MBD) show directly, for the first time, that the zinc is coordinated to the sulfur atoms of four cysteine residues with an average Zn-S bond length of 2.34+/-0.01 A. XPA-MBD was also expressed in minimal medium supplemented with cobalt nitrate to yield a blue-colored protein that was primarily (>95%) cobalt associated (CoXPA-MBD). EXAFS spectra collected on CoXPA-MBD show that the cobalt is also coordinated to the sulfur atoms of four cysteine residues with an average Co-S bond length of 2.33+/-0.02 A.

Structural features of the minimal DNA binding domain (M98-F219) of human nucleotide excision repair protein XPA

XPA, an essential protein in nucleotide excision repair (NER), interacts with damaged DNA and other proteins (RPA, ERCC1 and TFIIH) to remove a wide variety of chemically and structurally distinct DNA lesions from the eukaryotic genome. To understand the structural basis for the role of XPA in the repair process, the structure of the minimal DNA binding domain of human XPA [XPA-MBD (M98-F219)] was studied by NMR spectroscopy. A three-dimensional structure for XPA-MBD was generated using distance geometry and simulated annealing methods from NOE-based distance restraints, hydrogen bond and Zn-S distance restraints, and dihedral restraints. The structure calculations indicate that XPA-MBD contains elements of well-defined secondary structure interspaced with disordered loops organized into two non-interactive sub-domains: a zinc-binding core (D101-K137) and a loop-rich domain (L138-F219). The zinc-associated core contains an antiparallel beta-sheet (Y102-C105 and K110-M113) and an alpha-helix (C126-K137) separated by a poorly defined turn, reminiscent of the structure of the zinc-binding domain of the chicken erythroid transcription factor GATA-1 when bound to its cognate DNA sequence. The loop-rich domain contains a triple-strand antiparallel beta-sheet (L138-T140, L182-M178 and K163-K167), three loops (K151-L162, N169-D177 and Q208-F219) and three alpha-helices (K141-L150, K183-W194 and Q197-R207). The XPA-MBD structure is discussed in terms of known functions: binding single- and double-stranded DNA and binding RPA.

Purification, characterization and gene sequence analysis of a novel cytochrome c co-induced with reductive dechlorination activity in Desulfomonile tiedjei DCB-1

The sulfate-reducing bacterium, Desulfomonile tiedjei DCB-1, conserves energy for growth from reductive dechlorination of 3-chlorobenzoate via halorespiration. To understand this respiratory process better, we examined electron carriers from different cellular compartments of D. tiedjei. A 50-kDa cytochrome from the membrane fraction was found to be co-induced with dechlorination activity. This inducible cytochrome was extracted from the membrane fractions by Tris-HCl buffer containing ammonium sulfate at 35% saturation and was purified to electrophoretic homogeneity by phenyl superose, Mono Q, and hydroxyapatite chromatography. The purified cytochrome had a high-spin absorption spectrum. In a pH titration experiment, the absorption spectrum of the inducible cytochrome shifted to low spin at pH 13.2. The midpoint potential of the inducible cytochrome at pH 7.0 was -342 mV. The NH2-terminal amino acid sequence of the inducible cytochrome was determined and was used to obtain inverse PCR products containing the sequence of the gene encoding the inducible cytochrome. The ORF was 1398 bp and coded for a protein of 52.6 kDa. Two c-type heme-binding domains were identified in the COOH-terminal half of the protein. A putative signal peptide of 26 residues was found at the NH2-terminal end. The protein sequence was not found to have substantial sequence similarity to any other sequence in GenBank. We conclude that this is a c-type cytochrome substantially different from previously characterized c-type cytochromes.