[Effects of anteriolateral thigh perforator flap and fascia lata transplantation in combination with computed tomography angiography on repair of electrical burn wounds of head with skull exposure and necrosis]

Objective: To explore the effects of anteriolateral thigh perforator flap and fascia lata transplantation in combination with computed tomography angiography (CTA) on repair of electrical burn wounds of head with skull exposure and necrosis. Methods: Seven patients with head electrical burns accompanied by skull exposure and necrosis were admitted to our burn center from March 2016 to December 2017. Head CTA was performed before the operation. The diameters of the facial artery and vein or the superficial temporal artery and vein were measured, and their locations were marked on the body surface. Preoperative CTA for flap donor sites in lower extremities were also performed to track the descending branch of the lateral circumflex femoral artery with the similar diameter as the recipient vessels on the head, and their locations were marked on the body surface. Routine wound debridement and skull drilling were performed successively. The size of the wounds after debridement ranged from 12 cm×8 cm to 20 cm×12 cm, and the areas of skull exposure ranged from 8 cm×6 cm to 15 cm×10 cm. Anteriolateral thigh perforator flaps with areas from 13 cm×9 cm to 21 cm×13 cm containing 5-10 cm long vascular pedicles were designed and dissected accordingly. The fascia lata under the flap with area from 5 cm×2 cm to 10 cm×3 cm was dissected according to the length of vascular pedicle. The fascia lata was transplanted to cover the exposed skull, and the anteriolateral thigh perforator flap was transplanted afterwards. The descending branch of the lateral circumflex femoral artery and its accompanying vein of the flap were anastomosed with superficial temporal artery and vein or facial artery and vein before the suture of flap. The flap donor sites were covered by intermediate split-thickness skin graft collected from contralateral thigh or abdomen. Results: The descending branch of the lateral circumflex femoral artery and its accompanying vein were anastomosed with superficial temporal artery and vein in six patients, while those with facial artery and vein in one patient. All the flaps survived after the operation, and no vascular crisis was observed. Wound healing was satisfactory. One patient was lost to follow up. Six patients were followed up for 6 to 10 months. The patients were bald in the head operation area with acceptable appearance. No psychiatric symptom such as headache or epileptic seizure was reported. The flap donor sites were normal in appearance. The muscle strength of the lower extremities all reached grade V. The sensation and movement of the lower extremities were normal. Conclusions: Anterolateral thigh perforator flap with fascia lata transplantation can effectively repair electrical burn wounds of head with skull exposure and necrosis. The fascia lata can be used to protect the vascular pedicle of flaps, which is beneficial to the survival of the flap. Preoperative head and lower extremities CTA can provide reference for intraoperative vascular exploration in donor site and recipient area, so as to shorten operation time.

Direct Growth of Al2O3 on Black Phosphorus by Plasma-Enhanced Atomic Layer Deposition

Growing high-quality and uniform dielectric on black phosphorus is challenging since it is easy to react with O₂ or H₂O in ambient. In this work, we have directly grown Al₂O₃ on BP using plasma-enhanced atomic layer deposition (PEALD). The surface roughness of BP with covered Al₂O₃ film can reduce significantly, which is due to the removal of oxidized bubble in BP surface by oxygen plasma. It was also found there is an interfacial layer of PO _x in between amorphous Al₂O₃ film and crystallized BP, which is verified by both X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) measurements. By increasing temperature, the PO _x can be converted into fully oxidized P₂O₅.

[Comparison on the efficacy and safety of different occlusion devices for the treatment of patients with patent foramen ovale]

Objective: To compare the efficacy and safety of Cardi-O-fix patent foramen ovale (PFO) occluder and Amplatzer PFO occluder for the treatment of patients with PFO. Methods: A total of 246 consecutive patients (105 males and 141 females) with PFO were prospectively enrolled from May 30, 2013 to March 30, 2015 in our hospital. PFO interventional closure was applied according to the anatomical structure of the disease and patients' wishes.Cardi-O-fix PFO occluder was used in 180 cases (COF group), Amplatzer PFO occluder was used in the remaining 66 cases (Amp group). Post-procedure safety including recurrent stroke, transient ischemic attack, death, and complete closure rate, and efficacy including procedure related complications of different devices were compared during the 12 months follow-up. Results: (1) Rate of transient ischemic attack was similar between COF group and Amp group at 12 months after procedure(1.1%(2/180) vs. 1.5%(1/66), P=1.000). There was no recurrent stroke and death during the 12 months follow-up period.Complete closure rate was similar between COF group and Amp group at 12 months after the procedure(90.6%(163/180)vs. 86.4%(57/66), P=0.355). (2) Three cases(1.7%) of paroxysmal atrial fibrillation were observed in COF group during the 12 months follow-up period, 1 patient converted spontaneously to sinus rhythm and 2 patients received successful pharmacologic conversion and converted to sinus rhythm. One patient(1.5%)developed paroxysmal atrial fibrillation and was pharmacologically converted to sinus rhythm in the Amp group. There was no significant difference in rate of paroxysmal atrial fibrillation between the two groups(P=1.000). There was no complications such as occluder translocation, erosion, pericardial effusion and puncture site bleeding in the 2 groups during the 12 months follow-up. Conclusion: Efficacy and safety are similar for PFO treatment with Cardi-O-fix PFO occluder or Amplatzer PFO occluder in this patient cohort.

[Effect of trichostatin A on the osteogenic differentiation potential of periodontal ligament stem cells in inflammatory microenvironment induced by tumor necrosis factor-α stimulation]

OBJECTIVE

To compare the expression of histone deacetylase(HDAC)1-11 of human periodontal ligament stem cells(PDLSC)in normal and inflammatory microenvironments, and to investigate the effect of histone deacetylase inhibitor trichostatin A(TSA)on the osteogenic differentiation potential of PDLSC in inflammatory microenvironment induced by tumor necrosis factor-α(TNF-α)stimulation.

METHODS

PDLSC were isolated from periodontal ligament tissues obtained from the surgically extracted human teeth and cultured by single-colony selection. The expression of HDAC1-11 in cells with or without TNF-α(10 μg/L)stimulation was evaluated by quantitative real time-PCR(RT-PCR). The effect of TSA on cell proliferation was investigated by methyl thiazolyl tetrazolium(MTT)assay. The influence of TSA on osteogenic differentiation of PDLSC in inflammatory microenvironment with TNF-α stimulation was assessed by alizarin red staining, quantitative RT-PCR and Western blotting, respectively.

RESULTS

The expression of HDAC in PDLSC with TNF-α stimulation was significantly higher than that in normal PDLSC(P<0.05)(except HDAC7, P=0.243). TSA had no significant effect on PDLSC proliferation at the concentration of 50 nmol/L(P=0.232). The alizarin red staining showed that PDLSC in TNF-α group generated less mineralized nodule than the control group, while the cell matrix mineralization in TSA group was improved obviously. TNF-α had an inhibitory effect on the expression of osteogenesis related genes, runt-related transcription factor-2(RUNX2)and alkaline phosphatase(ALP), with relative gene expression ratio(experimental/control)decreased to 0.17 ± 0.02 and 0.32 ± 0.03, while TSA could significantly increase the genes' expression to 0.67±0.03 and 0.89±0.02(P<0.01). Western blotting test showed that in TNF-α group the expression of osteogenesis related proteins was obviously reduced, and compared with the TNF-α group, TSA could significantly promote the expression of proteinsin inflammatory microenvironment.

CONCLUSIONS

PDLSC in inflammatory microenvironment by TNF-α stimulation had a higher expression of HDAC than that in normal conditions. TSA, as a histone deacetylase inhibitor, could significantly promote the osteogenic differentiation potential of PDLSC in inflammatory microenvironment by suppressing HDAC.

[Relative analysis of platelet activation with bleeding risk in patients with primary immune thrombocytopenia]

目的

研究原发免疫性血小板减少症（ITP）患者血小板活化状态和出血程度的相关性。

方法

采用ITP特异性出血评价工具（ITP-BAT）对43例ITP患者进行出血评分及出血程度分级，应用流式细胞术检测二磷酸腺苷（ADP）激活前后血小板膜糖蛋白（GP）Ⅰb、Ⅱb/Ⅲa和P选择素表达。分析GPⅠb、GPⅡb/Ⅲa、P选择素表达与血小板计数、未成熟血小板比例的相关性；分析GPⅠb、GPⅡb/Ⅲa、P选择素表达与ITP患者出血程度的相关性，以及对中度以上出血患者风险评估的应用价值。

结果

ITP患者激活前血小板GPⅡb/Ⅲa、P选择素表达均高于正常对照组（65.69±10.73对7.16±0.99，t=4.130，P<0.001；15.43±1.41对12.55±1.03，t=2.070，P=0.043），GPⅠb表达低于正常对照组（240.11±24.93对295.11±22.15，t=2.417，P=0.020）。ITP患者ADP激活后血小板GPⅡb/Ⅲa表达高于正常对照组（133.96±12.17对39.67±4.99，t=5.256，P<0.001），而P选择素、GPⅠb表达低于正常对照组（37.09±3.94对109.77±23.66，t=3.901，P<0.001；149.06±19.14对205.73±21.00，t=2.070，P=0.043）。ADP激活后GPⅠb表达、ADP激活前后P选择素表达及ADP激活前后GPⅠb、P选择素表达比值与血小板计数相关（P<0.05）。ADP激活后P选择素表达、ADP激活前后P选择素表达比值与未成熟血小板比例相关（P<0.05）。ITP患者ADP激活后GPⅠb表达、ADP激活前后P选择素表达及ADP激活前后P选择素、GPⅡb/Ⅲa、GPⅠb表达比值在不同出血程度之间差异有统计学意义（P<0.05）。ADP激活前后GPⅠb表达比值是ITP患者中度以上出血的正性影响因素（OR=3.05，P=0.011），ADP激活前后P选择素、GPⅡb/Ⅲa表达比值是ITP患者中度以上出血的负性影响因素（OR=0.32，P=0.023；OR=0.04，P=0.006）。

结论

血小板活化指标能较准确地评估ITP患者出血程度，可以作为治疗参考指标和疗效观察指标。

Fine mapping and candidate gene analysis of Brtri1, a gene controlling trichome development in Chinese cabbage (Brassica rapa L. ssp pekinensis)

Trichomes are derived from the epidermis and constitute an ideal system for studying cell division in plants. Here, a Chinese cabbage doubled haploid (DH) line (FT) without trichomes was crossed with another DH line (PurDH-1) with trichomes to develop an F₂ population for fine mapping of trichome control genes. Genetic analysis showed that the trichome phenotype was controlled by a single dominant gene, Brtri1. Using 1226 glabrous individuals in the F₂ segregation population, Brtri1 was localized to a 16.84 kb region between markers Pur6-31 and Pur6-39 on chromosome A06. One of the four complete open reading frames within the mapping region, Bra025311, encodes a MYB transcription factor and is highly homologous to the trichome regulatory gene GL1 in Arabidopsis thaliana. It was thus regarded as a candidate gene for Brtri1. Comparative sequencing showed a 5-bp deletion in the third exon of Bra025311 in FT, resulting in a frame-shift mutation. No expression of Bra025311 was detected in FT. A co-dominant indel marker close to this mutation site was developed for marker-assisted selection in Chinese cabbage breeding.

Long-term exposure of K562 cells to benzene metabolites inhibited erythroid differentiation and elevated methylation in erythroid specific genes

Benzene is a common occupational hazard and a widespread environmental pollutant. Previous studies have revealed that 72 h exposure to benzene metabolites inhibited hemin-induced erythroid differentiation of K562 cells accompanied with elevated methylation in erythroid specific genes. However, little is known about the effects of long-term and low-dose benzene metabolite exposure. In this study, to elucidate the effects of long-term benzene metabolite exposure on erythroid differentiation, K562 cells were treated with low-concentration phenol, hydroquinone and 1,2,4-benzenetriol for at least 3 weeks. After exposure of K562 cells to benzene metabolites, hemin-induced hemoglobin synthesis declined in a concentration- and time-dependent manner, and the hemin-induced expressions of α-, β- and γ-globin genes and heme synthesis enzyme porphobilinogen deaminase were significantly suppressed. Furthermore, when K562 cells were continuously cultured without benzene metabolites for another 20 days after exposure to benzene metabolites for 4 weeks, the decreased erythroid differentiation capabilities still remained stable in hydroquinone- and 1,2,4-benzenetriol-exposed cells, but showed a slow increase in phenol-exposed K562 cells. In addition, methyltransferase inhibitor 5-aza-2'-deoxycytidine significantly blocked benzene metabolites inhibiting hemoglobin synthesis and expression of erythroid genes. Quantitative MassARRAY methylation analysis also confirmed that the exposure to benzene metabolites increased DNA methylation levels at several CpG sites in several erythroid-specific genes and their far-upstream regulatory elements. These results demonstrated that long-term and low-dose exposure to benzene metabolites inhibited the hemin-induced erythroid differentiation of K562 cells, in which DNA methylation played a role through the suppression of erythroid specific genes.

The influence of HOXA5-specific siRNA on the expression of Livin and Smac proteins

OBJECTIVE

To Knockdown Homeobox A5 (HOXA5) expression by HOXA5-specific siRNA and evaluate the effects on Livin and Smac proteins expression in acute T cell leukemia Jurkat cells.

MATERIALS AND METHODS

We designed and constructed HOXA5-specific siRNA, and using liposomes we transfected Jurkat cells with this siRNA. The experiment was designed for three groups: (i) experimental group with Jurkat cells transfected with HOXA5-specific siRNA (siRNA transfection group), (ii) negative control group (irrelevant siRNA transfection) with Jurkat cells transfected with pRNAT-U6.1-siD and (iii) normal control group (untransfected Jurkat cells, only with equivalent amounts of cells and medium). We used FQ-PCR and Western blot to detect the relative expression levels of HOXA5 mRNA and protein in each group separately. The Western blot was also used to detect Livin and Smac protein levels in Jurkat cells.

RESULTS

Expression levels of HOXA5 mRNA and protein were significantly reduced in the group with Jurkat cells transfected with HOXA5 siRNA (p<0.05). The expression of Livin protein was significantly down-regulated (p<0.05) while the expression of Smac protein was significantly up-regulated (p <0.05).

CONCLUSIONS

HOXA5-specific siRNA effectively silenced the HOXA5 gene expression and down-regulation of HOXA5 induced the down-regulation of Livin protein expression and up-regulation of Smac protein. We suggest the HOXA5 gene to be considered as the new target for acute leukemia gene therapy.

[Effect and mechanism of interleukin-8 expression induced by wood smoke particles in primary human airway epithelial cells]

OBJECTIVE

To investigate the effect and mechanism of interleukin-8 expression induced by wood smoke particles (WSP) in primary human airway epithelial cells.

METHODS

Primary human bronchial epithelial cells (HBEC) were collected through fiberbronchoscopic brushing and incubated with different concentration of WSP (0, 12.5, 25.0, 50.0, 100.0 μg/ml). Levels of IL-8 protein in cell culture supernatant were measured using enzyme-linked immune sorbent assay. The specific inhibitors for epidermal growth factor receptor (EGFR) and p38 kinase signaling pathways were employed to pretreat HBEC, respectively, prior to incubation with 100 μg/ml WSP to investigate the mechanism of IL-8 expression induced by WSP.

RESULTS

The expression of IL-8 was significant increased in a dose-dependent manner after exposure HBEC to different concentration of WSP for 24h. The levels of IL-8 expression were (4546.67±1421.42) ρg/ml in (PD153035+WSP) group and (2803.33±865.00) ρg/ml in (SB203580+WSP) group respectively, which were significant decreased compared with the level of (12896.67±1373.11) ρg/ml in WSP group (P<0.05).

CONCLUSION

WSP could induce IL-8 expression by means of EGFR and p38 signaling pathways.

Molecular cloning, expression of, and regulation by thyroid-hormone receptor α A in the half-smooth tongue sole Cynoglossus semilaevis during metamorphosis

To elucidate the effect of thyroid hormone receptor α A (thraa) on metamorphosis, the full length cDNA of half-smooth tongue sole Cynoglossus semilaevis was cloned. The relative gene transcript level of thraa at different development stages was quantified using real-time PCR. Transcription of thraa increased and declined rapidly during metamorphosis. Hyperthyroidism was induced in juveniles and larvae with exposure to T3 and T4, and hypothyroidism with thiourea (TU), 2-mercapto-1-methylimidazole (MMI). thraa mRNA was higher in fish treated for 6 days with MMI than in untreated controls, although inhibited larvae did not complete metamorphosis. The addition of exogenous T4 reversed this effect in the MMI-treated group, but not in the TU-treated group. In situ hybridization revealed progressive tail end of body growth and change during developmental stages, with corresponding changes in thraa expression. This process may be induced by thyroid hormones with thraa as a major mediator. The morphological changes of tip of the tail may be associated with the development of lateral swimming.

Study on application of GRACE scoring system on nursing of ACS patients

OBJECTIVE

The aim of this study is to analyze application effects of specialized emergency nursing mode based on Global Registry Acute Coronary Events (GRACE) scoring system on Acute Coronary System (ACS) patients.

PATIENTS AND METHODS

135 ACS cases in this hospital of the same period were selected and they were divided into control group (65 cases) and observation group (70 cases) according to random number method and their order of hospitalization. The standard specialized nursing mode was applied in the control group while specialized nursing mode based on GRACE scoring system was applied in observation group to compare treatment effects.

RESULTS

We found that average time of Door-to-Balloon, surgery time and length of stay in observation group were shortened and the occurrence rate of complications during and after surgery was significantly lowered. The remedy achievement ratio and satisfaction scores on nursing are increased and differences were of statistical significance (p<0.05).

CONCLUSIONS

The stratified nursing was used to ACS patients based on GRACE scoring system, which was able to significantly increase remedy achievement ratio and decrease complications and, therefore, nursing quality is improved.

Advance in the study on p38 MAPK mediated drug resistance in leukemia

Leukemia is a group of malignant clone diseases of hematopoietic stem cells, while drug resistance (DR) has become the primary cause of chemotherapy failure. p38 mitogen-activated protein kinase (p38MAPK) signaling pathway induces cell activation, proliferation and apoptosis in response to extracellular stimuli. Recent studies have shown that p38 MAPK signaling pathway is closely associated with DR in leukemia. The present article reviews the relationship between p38 MAPK signaling pathway and DR in leukemia.

Identification of long non-coding RNA involved in osteogenic differentiation from mesenchymal stem cells using RNA-Seq data

The aim of this study was to identify long non-coding RNA (lncRNA) associated with osteogenic differentiation from mesenchymal stem cells (MSCs) using high-throughput RNA sequencing (RNA-Seq) data. RNA-Seq dataset was obtained from the European Bioinformatics Institute (accession No. PRJEB4496), including two replicates each for immortalized mesenchymal stem cells iMSC#3 cultured in growth medium (GM) and differentiation medium (DM) for 28 days. The clean reads were aligned to a hg19 reference genome by Tophat and assembled by Cufflinks to identify the known and novel transcripts. RPKM values were calculated to screen for differentially expressed RNA. Novel lncRNA were screened based on various filter criteria. Subsequently, the underlying function of novel lncRNAs were predicted by functional annotation by ERPIN, a co-expression network was constructed by WGCNA and the KEGG pathway enriched by KOBAS. A total of 3171 RNA differentially expressed between the DM and GM groups (2597 mRNA and 574 lncRNA) were identified. Among the 574 differentially expressed lncRNA, 357 were known and 217 were novel lncRNA. Furthermore, 32 novel lncRNA were found to be miRNA precursors (including miR-689, miR-640, miR-601, and miR-544). A total of 14,275 co-expression relationships and 217 co-expression networks were obtained between novel lncRNA and mRNA. The differentially expressed lncRNA and mRNA were enriched into 6 significant pathways, including those for cancer, ECM-receptor interaction, and focal adhesion. Therefore, novel lncRNAwere identified and their underlying function predicted, which may provide the basis for future analyses of the role of lncRNA in osteoblastic differentiation.

Platelet parameters and expression of platelet membrane glycoprotein in childhood acute lymphoblastic leukemia

Platelet activation and functional changes were investigated in acute lymphoblastic leukemia (ALL) to provide the basis for early diagnosis and evaluation of curative effect. Platelet parameters, immature platelet fraction (IPF%), immature platelet count (IPC), P-selectin (CD62p) (PAC-1) expression were detected in ALL, ALL-complete remission-induced (CR1), and normal groups with an automatic blood cell analyzer and flow cytometer. CD62p and PAC-1 were higher in the ALL group before adenosine-5-diphosphate (ADP) activation than in the normal group (P < 0.05); PAC-1 expression was higher and lower in the ALL-CR1 group than in normal and ALL groups (P < 0.05), respectively. CD62p and PAC-1 expression was lower in the ALL group than in the normal group after ADP activation (P < 0.05); PAC-1 expression was lower and higher in the ALL-CR1 group than in normal and ALL groups, respectively (P < 0.05). Platelet count (PLT), mean platelet volume (MPV), platelet hematocrit (PCT), and platelet distribution width (PDW) were lower in the ALL group than in the ALL-CR1 group (P < 0.05). PLT, MPV, and PCT did not differ between the ALL-CR1 group and the normal group (P > 0.05). PDW did not differ statistically among all groups (P > 0.05). IPF% and IPC values were higher and lower in the ALL group than in normal and ALL-CR1 groups (P < 0.05), respectively. These did not differ significantly between the normal group and the ALL-CR1 group (P > 0.05). Therefore, ALL patients demonstrate platelet activation and platelet dysfunction; platelet parameters and membrane glycoprotein expression can be used to evaluate the effect of ALL.

Design and testing of an anti-scattering grid for medium-energy X-ray flash radiography

We propose an effective design of a 2-mm-thick tungsten anti-scattering grid for medium-energy X-ray imaging. First, the Monte Carlo simulation is carried out firstly, which indicates that the ratio of direct to scattered radiation can reach as high as 1.54. The grid for the testing is produced using precision mechanical drilling technology, with the typical size of 52.1×52.1 mm(2). Clear edge of the sample can be visualized in the image when the designed grid is used and the quality of the image is substantively improved.

Serum nerve growth factor level indicates therapeutic efficacy of 125I seed implantation in advanced pancreatic adenocarcinoma

OBJECTIVE

To evaluate serum nerve growth factor (NGF) as a marker in predicting effectiveness of 125I seed implantation in advanced pancreatic carcinoma.

PATIENTS AND METHODS

A total of 45 patients (30 males/15 females with mean age of 52.07±8.43 years) diagnosed with advanced pancreatic adenocarcinoma (PCa) between January 2011 to May 2014 were enrolled as PCa group in this study. Tumors were categorized as at least stage III with unresectionable condition by the TNM standard. The average tumour shortest diameter was 37.54±13.84 mm (18.50-71.20 mm). NGF level in serum before 125I seed implantation and in tumor tissue resected during surgery was measured by ELISA. After treatment, CT Scan was used to serially monitor the diameters of the tumour monthly for 6-month follow-up. RECIST was applied to evaluate the efficacy. Predictive value of serum and tumour derived NGF was evaluated based on ROC curve chart.

RESULTS

We found that the serum NGF level was significantly increased in PCa patients (775.60 ± 250.97 pg/ml) compared to the healthy control group (35.03 ± 25.36 pg/ml), after age and gender adjustment. In the PCa group, the serum NGF level positively correlated with that from loci tumor tissue (r=0.487). The serum NGF level was compared between the effective group (537.42 ± 122.61 pg/ml) and noneffective group (883.17 ± 217.79 pg/ml), and significant difference was detected (p<0.0001). Patients with lower serum NGF level had good response to the 125I seeds implantation. Taking cut-off at 649.59 pg/ml, 85.70% specificity and 90.30% sensitivity were achieved by ROC. Area under the Curve of serum NGF was 0.945, standard deviation was 0.032, 95% confidence interval was 0.882-1.000.

CONCLUSIONS

The level of serum NGF could be a referential index to predict the therapeutic efficacy of 125I seed implantation treatments in advanced pancreatic adenocarcinoma.

Developmental expression of inositol 1, 4, 5-trisphosphate receptor in the post-natal rat cochlea

Inositol 1, 4, 5-trisphosphate receptor (IP3R) has been established to be essential for hearing. However, the expression of IP3R in the cochlea in the period of auditory development remains unknown. We investigated the expression of IP3R in the developing rat cochlea using immunohistochemistry and real-time reverse transcription polymerase chain reaction (RT-PCR). We observed its presence in the developing rat cochlea, and changes in IP3R protein expressions from the early post-natal period to adult. At birth (post-natal day 0, P0), IP3R expression was only found in Hensen's cell. IP3R immunoreactivity first appeared in the sensory hair cells in the organ of Corti at P2. This localization was confirmed by means of double-labeling experiments with Myosin VIIA, a marker for cochlear hair cells. Colocalization of IP3R and Myosin VIIA from P2 to the second post-natal week suggested early expression of IP3R in developing inner and outer hair cells. Claudius' cells near the spiral ligament were labelled for IP3R from P8 onwards. Transient IP3R expression was observed in the stria vascularis in early post-natal rat from P4 to P8. Spiral ganglion neurons also exhibited weaker IP3R fluorescence signals during post-natal development. The results of RT-PCR demonstrated that all three IP3R isoforms (IP3R1, IP3R2, and IP3R3) were present in rat cochlea during four different developmental stages of cochlea, from P0 to P28. Present immunohistochemical evidence for both change and maintenance of expression of IP3R during post-natal development of the rat cochlea indicated the possible involvement of IP3R-mediated calcium signaling in cochlear development.

Preferentially regulated expression of connexin 43 in the developing spiral ganglion neurons and afferent terminals in post-natal rat cochlea

The expression pattern of connexin 43 (Cx43) in the cochlea is not determined and is controversial. Since the presence of Cx43 is essential for hearing, we re-examined its distribution during post-natal development of rat cochlea. Cx43 protein was expressed in spiral ganglion neurons (SGNs) and their neurite terminals innervating the inner and outer hair cells (IHCs and OHCs) as early as birth (postnatal day 0, P0), and persisted until P14. Double immunofluorescence staining, using two antibodies against Cx43 and TUJ1, a marker for all SGNs and afferent terminals, showed that immunoreactivity for Cx43 and TUJ1 was perfectly colocalized in SGNs and afferent terminals associated with the IHCs and OHCs. However, beyond P14, Cx43 immunostaining could no longer be detected in the region of the synaptic terminals at the bases of IHCs and OHCs (P17, adult). In contrast, Cx43 maintained its expression in SGNs into adulthood. We further performed quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) to identify the presence of Cx43 mRNA in the modiolus (mainly containing SGNs). Cx43 mRNA was higher at P8, compared with P1, and subsequently decreased at P14. These results indicated that Cx43 correlated with cochlear synaptogenesis and establishment of auditory neurotransmission.

ATRA and As₂O₃ regulate differentiation of human hematopoietic stem cells into granulocyte progenitor via alteration of HoxB8 expression

OBJECTIVE

This study aimed to investigate the effect of all-trans retinoic acid (ATRA) and/or arsenic trioxide (As2O3) on homeobox B8 (HOXB8) mRNA and protein expressions during the differentiation and proliferation of hematopoietic stem cells (HSCs) to colony forming unit-granulocyte (CFU-G) in order to explore the pathogenesis of leukemia mediated by HOXB8 at mRNA and protein level.

MATERIALS AND METHODS

Twelve cord blood samples were collected from the fetal placenta umbilical vein and cultured in vitro. The proliferation and differentiation of cord blood HSCs into CFU-G was continuously disrupted with 10 nmol/l of ATRA and/or 10 nmol/l of As2O3. The expression of HOXB8 mRNA and protein were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western-blot, respectively.

RESULTS

HOXB8 mRNA/protein expression was detected in control, ATRA, As2O3 and ATRA +As2O3 groups on days 3, 7, and 12 of culture. HOXB8 mRNA/protein expression was detectable on day 3, reached its highest level on day 7 and decreased on day 12. HOXB8 mRNA/protein expression in ATRA, As2O3 and ATRA+As2O3 was upregulated compared with control group (p < 0.05).

CONCLUSIONS

There is a positive relationship between HOXB8 gene expression and granulocyte progenitor hematopoiesis. ATRA/As2O3 up-regulate the expression of HOXB8 mRNA/protein, and treatment of leukemia with ATRA/As2O3 may regulate HOX gene expression.

Assessment of the nutritive value of whole corn stover and its morphological fractions

This study investigated the chemical composition and ruminal degradability of corn stover in three maize-planting regions in Qiqihaer, Heilongjiang Province, China. The whole stover was separated into seven morphological fractions, i.e., leaf blade, leaf sheath, stem rind, stem pith, stem node, ear husk, and corn tassel. The assessment of nutritive value of corn stover and its fractions was performed based on laboratory assays of the morphological proportions, chemical composition, and in situ degradability of dry matter (DM), neutral detergent fiber (NDF), and acid detergent fiber (ADF). The chemical composition of corn stover was significantly different from plant top to bottom (p<0.05). Among the whole corn stover and seven morphological fractions, leaf blade had the highest crude protein (CP) content and the lowest NDF and ADF contents (p<0.05), whereas stem rind had the lowest CP content and the highest ADF and acid detergent lignin (ADL) contents (p<0.05). Ear husk had significantly higher NDF content and relatively lower ADL content than other corn stover fractions. Overall, the effective degradability of DM, NDF, and ADF in rumen was the highest in leaf blade and stem pith, followed by ear husk. The results indicate that leaf blade, ear husk, and stem pith potentially have higher nutritive values than the other fractions of corn stover. This study provides reference data for high-efficiency use of corn stover in feeding ruminants.

Morphological effects of the nanostructured ceria support on the activity and stability of CuO/CeO2 catalysts for the water-gas shift reaction

Three CuO/CeO2 catalyst with different morphologies of ceria, namely nanospheres, nanorods and nanocubes, were synthesized and used to catalyze the water-gas shift (WGS) reaction. The reactivity tests showed that the Cu supported on the ceria nanospheres exhibited both the highest activity and superior stability when compared with the nanocube and nanorod ceria catalysts. Operando X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) and diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) methods were used to characterize these catalysts in their working state. High resolution electron microscopy (HRTEM, STEM) was used to look at the local atomic structure and nano-scale morphology. Our results show that the morphology of the ceria support, which can involve different crystal faces and concentrations of defects and imperfections, has a critical impact on the catalytic properties and influences: (1) the dispersion of CuO in the as-synthesized catalyst; (2) the particle size of metallic Cu upon reduction during the WGS reaction, (3) the stability of the metallic Cu upon variations of temperature, and (4) the dissociation of water on the ceria support. The nanosphere ceria catalyst showed an excellent water dissociation capability, the best dispersion of Cu and a strong Cu-Ce interaction, therefore delivering the best performance among the three WGS catalysts. The metallic Cu, which is the active species during the WGS reaction, was more stabilized on the nanospheres than on the nanorods and nanocubes and thus led to a better stability of the nanosphere catalyst than the other two architectures. Each catalyst exhibited a distinctive line-shape in the 800-1600 cm(-1) region of the DRIFTS spectra, pointing to the existence of different types of carbonate or carboxylate species as surface intermediates for the WGS.

Multimedia fate and source apportionment of polycyclic aromatic hydrocarbons in a coking industry city in Northern China

A steady state Level III fate model was established and applied to quantify source-receptor relationship in a coking industry city in Northern China. The local emission inventory of PAHs, as the model input, was acquired based on energy consumption and emission factors. The model estimations were validated by measured data and indicated remarkable variations in the paired isomeric ratios. When a rectification factor, based on the receptor-to-source ratio, was calculated by the fate model, the quantitatively verified molecular diagnostic ratios provided reasonable results of local PAH emission sources. Due to the local ban and measures on small scale coking activities implemented from the beginning of 2004, the model calculations indicated that the local emission amount of PAHs in 2009 decreased considerably compared to that in 2003.