弹力纤维醛品红法过染时解决方法的探讨

弹力纤维广泛分布于身体各处,在HE染色中呈淡红色,弹力纤维主要染色方法有Gomori醛品红法、Weigert间苯二酚碱性品红法、维多利亚蓝法等[1]。本科室主要采用Gomori醛品红法,笔者发现在醛品红染色结束时如果先用水冲掉醛品红染液再用70%乙醇分化,乙醇的分化作用会显著减弱,导致切片过染,背景过度着色,整个视野一片深紫色(图1),且不能再被乙醇洗脱,背景过深,影响诊断。鉴于此,笔者通过实践和摸索,依据酸碱度分三种类型进行试验分别比较过染褪色和褪色后再次染色的效果,现介绍如下。

瑞氏染色过染后的补救办法

血片进行瑞氏染色时,由于多种原因,可使染色结果不佳。对于偏酸、偏碱,细胞着色浅的结果,可以采用直接复染的方法校正,而对于染液、缓冲液比例不当、染色时间过长、染液干涸等引起过深,染料沉渣附着的结果就很难处理。笔者在实际工作中摸索出一种较为理想的补救办法:将过染血片置于95％乙醇液中荡洗脱色。

Influence of Rainfall Run-off in Hydrologic Process on Non-Point Pollution

[Objective] This study aimed to study on influence of rainfall runoff on non-point pollution and to reduce the pollution through control of the contamination produced from rainfall runoff. [Method] In order to explore effective methods to decrease non-point pollution, we conducted analysis on hydrological process of rainfall runoff, interaction mechanism between the process and non-point pollutants, the influence on non-point pollution and hydrological model application in the research. [Result] It was proved that rainfall runoff was the main factor of non-point pollution. Control from source strengthened clearing and controlling of non-point pollutants on the ground. Growing plants in slope effectively reduced the scour and erosion of rainfall runoff on soil. The study became simple thanks for the hydrological process. [Conclusion] The research indicated that non-point pollution would be effectively reduced through control of rainfall runoff.

小麦新品种——小冰麦33

高产、高蛋白、多抗小麦新品种——小冰麦33,近日由东北师范大学科研人员研制成功。小冰麦33是运用现代生物技术,通过染色体工程途径将野生天兰冰草抗病、高蛋白基因转移到小麦染色体上。

Persistent occult hepatitis B virus infection:Experimental findings and clinical implications

Hepatitis B virus (HBV) is a highly pathogenic virus that causes chronic liver diseases in millions of people globally. In addition to a symptomatic, serologically evident infection, occult persistent HBV carriage has been identified since nucleic acid amplification assays of enhanced sensitivity became introduced for detection of hepadnaviral genomes and their replicative intermediates. Current evidence indicates that occult HBV infection is a common and long-term consequence of resolution of acute hepatitis B. This form of residual infection is termed as secondary occult infection (SOI). The data from the woodchuck model of HBV infection indicate that exposure to small amounts of hepadnavirus can also cause primary occult infection (POI) where virus genome, but no serological makers of exposure to virus, are detectable, and the liver may not be involved. However, virus replicates at low levels in the lymphatic system in both these forms. We briefly summarize the current understanding of the nature and characteristics of occult hepadnaviral persistence as well as of its documented and expected pathological consequences.

Source-sink landscape spatial characteristics and effect on non-point source pollution in a small catchment of the Three Gorge Reservoir Region

The source and sink landscape patterns refer to landscape types or units that can either promote positive evolvement of non-point source(NPS) pollution process, or can prevent/defer the ecological process, respectively. Therefore, the role of a catchment landscape pattern in nutrient losses can be identified based on the spatial arrangement of source and sink landscapes. To reveal the relations between landscape spatial characteristics and NPS pollution in small catchment, a case study was carried out in a Wangjiagou small catchment of the Three Gorges Reservoir Region(TGRR), China. Google earth imagery for 2015 were processed and used to differentiate source and sink landscape types, and six subcatchments were selected as sample regions for monitoring nitrogen and phosphorus nutrients.Relative elevation, slope gradient and relative flow length was used to construct the Lorenz curves of different source and sink landscape types in the catchment, in order to assess the source and sink landscape spatial characteristics. By calculating the location-weighted landscape indices of each subcatchment and total catchment, the landscape spatial load characteristics affecting the NPS pollution was identified, with a further Pearson correlation analysis for location-weighted landscape indices and nitrogen-phosphorus monitoring indicators. The analysis of Lorenz curve has revealed that the obtained distribution trend of Lorenz curve and curve area quantified well the spatial characteristics of source and sink landscape pattern related to the relative elevation, slope gradient and relative flow length in small catchment. Results of Pearson correction analysis indicated that location-weighted landscape index(LWLI) combining of terrain and landscape type factor did better in reflecting the status of nitrogen and phosphorus loss than the indices related to relative elevation, slope gradient and relative flow length.

Gel Filtration Chromatography Combined with Bradford Method for Determination of Total Residual Protein in Ferment Antibiotics

Aim A novel method has been developed for evaluation of the levels of total residual protein in antibiotics produced by fermentation using gel filtration chromatography (GFC) combined with Bradford assay based on determination of residual protein in lincomycin hydrochloride. Methods The chromatographic conditions were SuperdexTM peptide column, 0.01 mol*L-1 phosphate buffer solution as mobile phase, and flow rate of 1 mL·min-1. Five hundred microliters of lincomycin hydrochloride solution (3 g of lincomycin hydrochloride dissolved in 10 mL of mobile phase) was injected into the chromatograph and the eluted solution was collected between 6 min and 14.5 min (protein eluted from column within this period), and the residual content of total protein in the eluted solution was assayed using Bradford assay method. Results The average recovery was more than 90% for bovine serum albumin, the calibration equation for the range of 0-12 μg·mL-1 of protein was y=-0.002 4x2+0.064 2x+0.002 9, r2=0.999 9, RSD=0.1%-0.9%, and the LOD and LOQ were 3 and 10 ng·mL-1 of protein, respectively. Conclusion The novel method for determining the residual protein in ferment antibio-tics is simple, rapid, and precise.

Increased presence of effector lymphocytes during Helicobacter hepaticus-induced colitis

AIM： To identify and characterize drosophila mothers against decapentaplegic （SMAD）3-dependent changes in immune cell populations following infection with He- Iicobacter hepaticus （H. hepaticus）. METHODS： SMAD3/ （n = L9） and colitis-resistant SMAD3＋/ （n = 24） mice （8-10 wk of age） were in- fected with/-/, hepaticus and changes in immune cell populations [T lymphocytes, natural killer （NK） cells, T regulatory cells] were measured in the spleen and mesenteric lymph nodes （MsLNs） at 0 d, 3 d, 7 d and 28 d post-infection using flow cytometry. Genotype-dependent changes in T lymphocytes and granzyme B＋ cells were also assessed after 28 d in proximal colon tissue using immunohistochemistry. RESULTS： As previously observed, SMAD3＋, but not SMAD3＋/- mice, developed colitis, peaking at 4 wk post-infection. No significant changes in T cell subsets were observed in the spleen or in the MsLNs between genotypes at any time point. However, CD4＋ and CD8＋/ CD62L＋＋ cells, an effector T lymphocyte population, as well as NK cells （NKp46/DX5＋） were significantly higher in the MsLNs of SMAD3/ mice at 7 d and 28 d post-in- fection. In the colon, a higher number of CD3＋ cells were present in SMAD3＋ compared to SMAD3＋/- mice at base- line, which did not significantly change during infection. However, the number of granzyme B＋ cells, a marker of cytolytic lymphoo/tes, significantly increased in SMAD3＋ mice 28 d post-infection compared to both SMAD3＋/- mice and to baseline values. This was consistent with more severe colitis development in these animals. CONCLUSION： Data suggest that defects in SMAD3 signaling increase susceptibility to H. hepaticus-induced colitis through aberrant activation and/or dysregulation of effector lymphoo/tes.

Field-Scale Contaminant Transport Through Soils:Current Understanding and Open Questions

Agro-chemical transport processes at different scales are discussed and relevant opening questions areidentified by literature review to make some suggestions concerning the improvement of research methods forfield scale solute transport by aid of evaluation of existing models, and examining transport behaviors of solutein vadose zones on different scales. The results indicate that present research progress and understanding onfield scale solute transport have not yet been enough to guarantee the use of our models for the management offield solute movement. Much more research work needs to be done, particularly, in aspects of high resolutionof spatial structures relevant to the hydraulic and transport properties, explicit numerical simulation of actualstructure on field scale and field measurement corroborated with model development.

Experimental Study on a New Dual-Layer Granular Bed Filter for Removing Particulates

A new dual-layer granular bed filter for hot gas cleanup was invented and studied experimentally. Fine sand,0.5-1 mm grain size and about 1350 kg/m3 bulk density,was used as the lower layer of the filter. Expanded perlite par-ticles,2-5 mm grain size and about 70 kg/m3 bulk density,was used for the upper layer of the filter in this study. It was confirmed that the sizes and densities of these two media matched well; the binary media remained in complete segre-gation during regeneration by fluidization. Test results show that the filtration of the expanded perlite particle layer was characterized as "deep bed filtration." Filtration of the fine sand layer was "surface cake filtration." The expanded per-lite particle layer contributed about 90% to the bed dust capacity,but only about 20% to the total bed pressure drop,which increased the bed dust capacity ten fold compared to a single-layer bed of the same sand and the same total bed pressure drop. The dust cake on the surface of the fine sand layer raised the collection efficiencies to over 99.99%.

Research progress on aging of organic pollutants in geosorbents:a review

Geosorbents are the main host of anthropogenic organic pollutants and play a vital role in their fate and transport in the natural environment.Soil and sediment are the most common and abundant geosorbents in the natural environment;their interactions with organic pollutants,especially sorption and desorption processes,have been extensively studied from the perspectives of thermodynamics and kinetics.Recently,the aging of organic pollutants in geosorbents has drawn increased attention,leading to an improved understanding of interactions between organic pollutants and geosorbents and informing remediation criteria.Aging has been deemed important in accurately assessing ecologic and health risks of organic pollutants,and both positive and negative impacts have been reported in studies of natural and artificial sorbents.This paper summarizes recent research progress on organic pollutant aging in geosorbents,including related mechanism research,influence factors,bioavailability assessments,and biological and physicochemical remediation of aged organic pollutants.We also discuss issues in the current research and bring forward suggestions for future study.

Screening Helicobacter pylori genes induced during infection of mouse stomachs

AIM:To investigate the effect of in vivo environment on gene expression in Helicobacter pylori(H.pylori) as it relates to its survival in the host.METHODS:In vivo expression technology(IVET) systems are used to identify microbial virulence genes.We modified the IVET-transcriptional fusion vector,pIVET8,which uses antibiotic resistance as the basis for selection of candidate genes in host tissues to develop two unique IVET-promoter-screening vectors,pIVET11 and pIVET12.Our novel IVET systems were developed by the fusion of random Sau3A DNA fragments of H.pylori and a tandem-reporter system of chloramphenicol acetyltransferase and beta-galactosidase.Additionally,each vector contains a kanamycin resistance gene.We used a mouse macrophage cell line,RAW 264.7 and mice,as selective media to identify specific genes that H.pylori expresses in vivo.Gene expression studies were conducted by infecting RAW 264.7 cells with H.pylori.This was followed by real time polymerase chain reaction(PCR) analysis to determine the relative expression levels of in vivo induced genes.RESULTS:In this study,we have identified 31 in vivo induced(ivi) genes in the initial screens.These 31 genes belong to several functional gene families,including several well-known virulence factors that are expressed by the bacterium in infected mouse stomachs.Virulence factors,vacA and cagA,were found in this screen and are known to play important roles in H.pylori infection,colonization and pathogenesis.Their detection validates the efficacy of these screening systems.Some of the identified ivi genes have already been implicated to play an important role in the pathogenesis of H.pylori and other bacterial pathogens such as Escherichia coli and Vibrio cholerae.Transcription profiles of allivi genes were confirmed by real time PCR analysis of H.pylori RNA isolated from H.pylori infected RAW 264.7 macrophages.We compared the expression profile of H.pylori and RAW 264.7 coculture with that of H.pylori only.Some genes such as cag A,vac A,lpx C,mur I,tlp C,trx B,sod B,tnp B,pgi,rbf A and inf B showed a 2-20 fold upregulation.Statistically significant upregulation was obtained for all the above mentioned genes(P < 0.05).tlp C,cag A,vac A,sod B,rbf A,inf B,tnp B,lpx C and mur I were also significantly upregulated(P < 0.01).These data suggest a strong correlation between results obtained in vitro in the macrophage cell line and in the intact animal.CONCLUSION:The positive identification of these genes demonstrates that our IVET systems are powerful tools for studying H.pylori gene expression in the host environment.

Intestinal permeability in rats with CCI4-induced portal hypertension

AIM： To investigate the intestinal barrier changes in rats with CCh-induced portal hypertension. METHODS： The permeability of intestinal barrier detected by Lanthanum as a tracer was evaluated in rats. Bacterial translocation and plasma endotoxin were also determined. RESULTS： The incidence of bacterial translocation was 85% in rats with CCh-induced portal hypertension, which was significantly higher than that in control rats （20%, P〈0.01）. Plasma endotoxin level was significantly higher in experimental group than in control group. Permeability of the epithelial mucosa and pathological alteration were increased in the ileum and the microvilli became shorter and thinner in rats with portal hypertension. CONCLUSION： Bacterial translocation occurs in rats with CCh-induced portal hypertension and increased permeability between epithelial cells contributes to the translocation.

Gene cloning and prokaryotic expression of recombinant flagellin A from Vibrio parahaemolyticus

The Gram-negative Vibrio parahaemolyticus is a common pathogen in humans and marine animals. Bacteria flagellins play an important role during infection and induction of the host immune response. Thus, flagellin proteins are an ideal target for vaccines. We amplified the complete flagellin subunit gene （tTaA） from V. parahaemolyticus ATCC 17802. We then cloned and expressed the gene into Escherichia coli BL21 （DE3） cells. The gene coded for a protein that was 62.78 kDa. We purified and characterized the protein using Ni-NTA affinity chromatography and Anti-His antibody Western blotting, respectively. Our results provide a basis for further studies into the utility of the FlaA protein as a vaccine candidate against infection by Vibrio parahaemolyticus. In addition, the purified FlaA protein can he used for further functional and structural studies.

Water Analysis for Heavy Metals Content in Selected Boreholes in Port Harcourt Metropolis （A Case Study during 2010-2011）

Underground water （Borehole） has been the main alternative source of drinking water for most communities in my country. Previous studies have revealed high levels of contamination. The origin of which can be attributed to geochemical processes, combustion of fossil fuels, mining and anthropogenic activities. Most borehole water and well water in local communities of Nigeria are not safe for drinking due to heavy industrial and environmental pollution. This study was undertaken to assess the quality in some selected boreholes in the Port Harcourt metropolis for a period of two years. Borehole water samples were randomly collected from thirteen boreholes in a local community in plastic bottles （100 mL） in the months of September for the years of study （2010 ＆ 2011）. Four out of the seven heavy metals analyzed were found to be present in the first year of study. These were Fe, Cu, Mn and Zn. In the second year of study, Pb, Cr, Fe and Co were not detected in all of the samples except Cu and Fe which were present in only two samples. Mn and Zn were found to be present in all of the samples for both years of study.

Research on Existing Pattern of Carbon and Its Removal from Fly Ash

Fly ash is a fine and dispersed powder discharged from power station after the coal being burned. With the deepening of people’s recognition about the pollution problem of fly ash, the ways of utilizing fly ash are gradually increasing. Utilizing value of fly ash is closely related to the unburned carbon content.On the basis of analysis of modern testing method,a fundamental thinking is theoretically posed for decreasing unburned carbon content from fly ash by a dry removing carbon technology. The triboelectric separation method shown that the above mentioned thinking of dry removing carbon from fly ash is practical.

Bicarbonate activation of hydrogen peroxide: A new emerging technology for wastewater treatment

The serious limitations of available technologies for decontamination of wastewater have compelled researchers to search for alternative solutions. Catalytic treatment with hydrogen peroxide, which appears to be one of the most efficient treatment systems, is able to degrade various organics with the help of powerful ·OH radicals. This review focuses on recent progress in the use of bicarbonate activated hydrogen peroxide for wastewater treatment. The introduction of bicarbonate to pollutant treatment has led to appreciable improvements, not only in process efficiency, but also in process stability. This review describes in detail the applications of this process in homogeneous and heterogeneous systems. The enhanced degradation, limited or lack of leaching during heterogeneous degradation, and prolonged catalysts stability during degradation are salient features of this system. This review provides readers with new knowledge regarding bicarbonate, including the fact that it does not always harm pollutant degradation, and can significantly benefit degradation under some conditions.

Peritrophin-like protein from Litopenaeus vannamei (LvPT) involved in white spot syndrome virus (WSSV) infection in digestive tract challenged with reverse gavage

The peritrophic membrane plays an important role in the defense system of the arthropod gut. The digestive tract is considered one of the major tissues targeted by white spot syndrome virus （WSSV） in shrimp. In this study, the nucleotide sequence encoding peritrophin-like protein of Litopenaeus vannamei （LvPT） was amplified from a yeast two-hybrid library of L. vannamei. The epitope peptide of LvPT was predicted with the GenScript OptimumAntigenTM design tool. An anti-LvPT polyclonal antibody was produced and shown to specifically bind a band at -27 kDa, identified as LvPT. The LvPT protein was expressed and its concentration determined. LvPT dsRNA （4 pg per shrimp） was used to inhibit LvPT expression in shrimp, and a WSSV challenge experiment was then performed with reverse gavage. The pleopods, stomachs, and guts were collected from the shrimp at 0, 24, 48, and 72 h post-infection （hpi）. Viral load quantification showed that the levels of WSSV were significantly lower in the pleopods, stomachs, and guts of shrimp after LvPT dsRNA interference than in those of the controls at 48 and 72 hpi. Our results imply that LvPT plays an important role during WSSV infection of the digestive tract.

Modeling of the Dyeing Uptake Rate for Direct Dyestuff on Cotton in Batch Dyeing Process Based on Grey System Theory

The grey system theory, with the characteristics of fewer modeling data and higher accuracy, was employed to model the batch dyeing process for the purpose of accurate online control. The GM（1, 1） and GM （0, N） models of the grey system theory were discussed for their feasibilities of modding for batch dyeing process. The combination of direct dyestuff Fast Red F3B on cotton was chosen as a representative of the common dyeing method for describing the modeling process. Firstly, the GM（ 1, 1 ） model and the GM（1, 1） combined with GM（0, N） model were employed to model the equilibrium percentage of dyeing uptake rate. Secondly, an integrated dyeing uptake rate model with three factors （ temperature, salt concentration, and pH） was established based on the adsorption rate equation. Experimental results show that this model has higher accuracy and beetler generalization ability, which can predict the results of batch dyeing process. Due to the application of grey system theory, the model has a lot of advantages, such as being easy to determine the parameter value and small amount of calculation. So it can also be suitable for the same type of combination of dyestuff-fahric by changing the parameters value only.

Successful interferon desensitization in a patient with chronic hepatitis C infection

Treatment of hepatitis C, even when absolutely necessary, is almost impossible when interferon cannot be administered for any reason. We report a 65-year-old patient with chronic hepatitis C virus (HCV) infection and fibrosis, who was unable to receive interferon because of systemic hypersensitivity. The patient was desensitized successfully through gradual incremental exposure to interferon, and HCV infection was eradicated after a complete course of treatment, with no further allergic reactions. This case report that describes successful eradication of hepatitis C in a patient with advanced liver disease after desensitization to interferon revealed that desensitization may not necessarily damage the therapeutic efficacy of the drug.