Multiple transcription factor profiling by enzyme-linked immunoassay

Transcription factor-DNA interactions have been widely studied in the regulation of gene expression. We have established an enzyme-linked immunoassay platform to quantify specific transcriptionfactor-DNA interactions. In our assay, dsDNA immobilized on a 96-well plate captures the transcriptionfactor from the nuclear extract of mammalian cells. The DNA-bound transcription factor is detected and quantified by enzyme-linked immunoassay using a transcription factor-specific antibody. We have profiled multiple transcription factors involved in inflammation including NFkappaB p50, NFkappaB p65, c-Rel, c-Fos, CREB-1, and ATF-2. When compared with the traditional electrophoretic mobility shift assay, the enzyme-linked immunoassay shows a 10-fold higher sensitivity, eliminates the use of radioactivity, allows for a high-throughput format, and is faster.

Alpha-glucosidase inhibition from a Chinese medical herb (Ramulus mori) in normal and diabetic rats and mice

Alpha-glucosidase inhibitors are oral antidiabetic drugs. A traditional Chinese medical herb, Sangzhi (Ramulus mori), appears to have properties similar to those of alpha-glucosidase inhibitors. The effects of an aqueous extract of Shangzhi (SZ) were studied in normal and alloxan diabetic rats and mice, and these results compared with those for acarbose, an alpha-glucosidase inhibitor. In our grade-dose studies, SZ was found to lower and prolong the zenith of blood glucose concentration (ZBG) after sucrose or starch loading and stabilize blood glucose levels in fasting normal and alloxan diabetic mice. After 2 weeks of SZ administration with high-calorie chow or a normal diet, the fasting and non-fasting blood glucose concentrations in alloxan diabetic mice and rats were decreased. In alloxan rats, the blood fructosamine concentration was lowered. Results for acarbose and SZ were similar. These indicate that SZ has alpha-glucosidase inhibitory effects.

Catalytically assisted electrochemical oxidation of dye Acid Red B

This study focused on the degradation of dye Acid Red B in a catalytic electrolysis system with a semiconductor suspended in the electric field. The study showed that the addition of titanium dioxide substantially enhances the degradation of dye and that a semiconductor catalyst can improve electrolysis efficiency. This catalytic system has great potential to be applied commercially with the development of the catalyst. Analytical measurements show that some acidic compounds are produced in the treatment process and that biodegradability of the solution increases after electrolysis because of the breakdown of molecules. The UV-visible spectrum also indicates that the conjugated bonds of dye Acid Red B must be destroyed and that the molecules are broken into small ones. Furthermore, the results from the IR spectrum indicate that the nitrogen-nitrogen double bond of dye Acid Red B must be oxidized to nitrate. Electrochemical measurements show an apparent dye oxidation peak from 0.65 to 0.85 V (versus the saturated calomel electrode) in dye solution (10 g/L), confirming that dye is oxidized in this catalytic system.

Interaction with BRCA2 suggests a role for filamin-1 (hsFLNa) in DNA damage response

The BRCA2 tumor suppressor plays significant roles in DNA damage response. The human actin binding protein filamin-1 (hsFLNa, also known as ABP-280) participates in orthogonal actin network, cellular stress responses, signal transduction, and cell migration. Through a yeast two-hybrid system, an in vitro binding assay, and in vivo co-immunoprecipitations, we identified an interaction between BRCA2 and hsFLNa. The hsFLNa binding domain of BRCA2 was mapped to an internal conserved region, and the BRCA2-interacting domain of hsFLNa was mapped to its C terminus. Although hsFLNa is known for its cytoplasmic functions in cell migration and signal transduction, some hsFLNa resides in the nucleus, raising the possibility that it participates in DNA damage response through a nuclear interaction with BRCA2. Lack of hsFLNa renders a human melanoma cell line (M2) more sensitive to several genotoxic agents including gamma irradiation, bleomycin, and ultraviolet-c light. These results suggest that BRCA2/hsFLNa interaction may serve to connect cytoskeletal signal transduction to DNA damage response pathways.

The problems and strategy relevant to the quality management of clinical laboratories

AIM

This study is aimed to discuss the present situation, existing problems, and relevant measures concerning the management of clinical laboratories in China.

METHODS

This study was carried out through the analysis of the problems relevant to the quality management of the laboratory medicine, based on the advanced experiences of ISO and developed countries in the management of clinical laboratories.

RESULTS

Many problems still remain unsolved concerning the quality management of clinical laboratories.

CONCLUSION

Only legalized and standardized management guarantees the quality of clinical inspection.

[Enhancement of bacillus Calmette-Guerin attachment to the bladder wall: experimental study]

OBJECTIVE

To provide experimentally a scientific basis for enhancement of bacillus Calmette-Guerin (BCG) antineoplastic effect.

METHODS

Thirty rabbits were equally divided into five groups (groups A, B, C, D, and E) and the bladder mucosa of every rabbit was injured by electrocautery, cryocautery and incision on the left lateral wall, right lateral wall and posterior wall respectively. Then different drugs were instilled into bladders. Group A: pure phosphate-buffered sodium instillation (PBS); group B: PBS and radiolabeled BCG (3H-BCG) instillation; group C and group D: epsilon-aminocaproic acid or para-aminomethyl benzoic acid and 3H-BCG instillation; group E: heparin and 3H-BCG instillation. After instillation, every injured bladder wall and non-injured wall (anterior wall of bladder) were surgically removed and digested. The quantity of BCG adherence was determined by liquid scintillation counter.

RESULTS

The quantity of BCG attached to injured bladder wall was significantly higher than that of non-injured wall (P < 0.001). The mean level of group C or group D was significantly higher than that of group B (P < 0.001) while the mean level of group E was significantly lower than that of group B (P < 0.001).

CONCLUSION

For experimental rabbits, intravesical instillation of fibrin clot stabilizer EACA or PAMBA can enhance BCG attachment to the bladder wall while fibrin clot inhibitor heparin inhibits it.

[The effects of BDP on the inflammatory cells in nasal secretions of the patients with allergic rhinitis]

OBJECTIVE

To study the effects of beclomethasone dipropionate (BDP) on the inflammatory cells in nasal secretions of the patients with allergic rhinitis.

METHOD

The variation of intercellular RNA and RNA/DNA ratio of the eosinophils, neutrocyte and lymphocyte in the nasal secretions were observed under the laser scanning confocal microscopy and technology of fluorescence.

RESULT

The scanning images displayed that either in eosinophils or in neutrocyte, the fluorescence signal of intercellular RNA was significantly decreased after BDP treatment, and the intercellular RNA/DNA ratio was significantly reduced (eosinophils group P < 0.001, and neutrocyte group P < 0.01). The fluorescence singal of lymphocyte intercellular RNA and RNA/DNA ratio were not significantly changed (P > 0.05).

CONCLUSION

BDP can reduce the content of intercellular RNA of the eosinophils and neutrocyte. The anti-inflammation function of BDP is realized by regulating the intercellular RNA synthesize and/or RNA degradation, and by inhibiting the intercellular inflammatory medium production. BDP does not directly influence the intercellular RNA metabolize of the lymphocyte.

Overexpression of human RAD51 and RAD52 reduces double-strand break-induced homologous recombination in mammalian cells

Double-strand breaks (DSBs) can be repaired by homologous recombination (HR) in mammalian cells, often resulting in gene conversion. RAD51 functions with RAD52 and other proteins to effect strand exchange during HR, forming heteroduplex DNA (hDNA) that is resolved by mismatch repair to yield a gene conversion tract. In mammalian cells RAD51 and RAD52 overexpression increase the frequency of spontaneous HR, and one study indicated that overexpression of mouse RAD51 enhances DSB-induced HR in Chinese hamster ovary (CHO) cells. We tested the effects of transient and stable overexpression of human RAD51 and/or human RAD52 on DSB-induced HR in CHO cells and in human cells. DSBs were targeted to chromosomal recombination substrates with I-SceI nuclease. In all cases, excess RAD51 and/or RAD52 reduced DSB-induced HR, contrasting with prior studies. These distinct results may reflect differences in recombination substrate structures or different levels of overexpression. Excess RAD51/RAD52 did not increase conversion tract lengths, nor were product spectra otherwise altered, indicating that excess HR proteins can have dominant negative effects on HR initiation, but do not affect later steps such as hDNA formation, mismatch repair or the resolution of intermediates.

Fatty acid composition of lysophosphatidic acid and lysophosphatidylinositol in plasma from patients with ovarian cancer and other gynecological diseases

OBJECTIVE

We previously reported that plasma levels of total lysophosphatidic acid (LPA) represented a potential biomarker for ovarian cancer and other gynecological cancers [1]. However, total LPA is composed of different LPA species with distinct fatty acid chains. The major objective of the current study, therefore, was to determine whether one or more specific fatty acid LPA species was associated with disease or disease staging. If this was determined, these species could be useful in further improving the sensitivity and/or specificity of this biomarker for the diagnosis and/or prognosis of the disease. Because lysophosphatidylinositol (LPI) co-migrates with LPA, this study represents the analysis of combined molecular species from both lysolipid classes.

METHODS

The patient population, sample collection, and analyses have been reported previously [1]. Lipids were hydrolyzed from the LPA band on thin-layer chromatography plates. The following individual fatty acid species were analyzed by gas chromatography: palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2), arachidonic acid (20:4), and docosahexaenoic acid (22:6). The LPA/LPI fatty acid composition levels were analyzed and compared with disease status.

RESULTS

Distinct plasma LPA/LPI fatty acid chain species were not associated with ovarian or other gynecological cancers, compared to patients with benign gynecological disease or healthy controls. However, an increased presence of unsaturated fatty acids in plasma LPA/LPI was found in patients with late-stage or recurrent ovarian cancer and possibly with other gynecological cancers.

CONCLUSIONS

Analysis of individual fatty acid species present in plasma LPA/LPI do not appear to enhance the sensitivity or specificity of total LPA/LPI as a marker for gynecological cancer detection. However, our results suggest that increased LPA/LPI species with unsaturated fatty acid chains may be associated with late-stage or recurrent ovarian cancer.

Long-term colonization levels of Helicobacter hepaticus in the cecum of hepatitis-prone A/JCr mice are significantly lower than those in hepatitis-resistant C57BL/6 mice

Helicobacter hepaticus infection causes hepatitis in A/JCr mice but mild or no disease in C57BL/6 mice. Colonization of H. hepaticus in the cecum of experimentally infected A/JCr and C57BL/6 mice was quantified by use of real-time polymerase chain reaction (PCR) analysis with primers for the H. hepaticus cdtB gene and mouse 18srRNA. Eight-week-old mice were experimentally (n = 48) or sham (n = 24) infected with H. hepaticus, then were necropsied 6 months after infection. Liver specimens from experimentally infected mice had negative results of PCR analysis for H. hepaticus; thus, real-time quantification was not attempted. Quantitative PCR analysis of H. hepaticus in cecal specimens indicated that C57BL/6 mice were colonized to a greater extent than were A/JCr mice (P < 0.006). Appreciable typhlitis was not observed, but was consistent with that of previous reports; A/JCr mice developed more severe parenchymal necrosis, portal inflammation, and phlebitis in the liver (P < 0.0001), with mild disease observed in infected C57BL/6 mice. Thus, hepatitis in A/JCr mice caused by H. hepaticus infection is associated with significantly lower colonization levels of H. hepaticus in the cecum, compared with those of hepatitis-resistant C57BL/6 mice. Host responses of A/JCr mice that limit cecal colonization with H. hepaticus may have important roles in the pathogenesis of hepatic lesions.

[Introduction of Vitreoscilla hemoglobin gene in a recombinant E. coli for PHB production]

Vitreoscilla hemoglobin gene (vgb) was introduced into the recombinant Escherichia coli VG1(pTU14) for production of poly-beta-hydroxybutyrate (PHB), in order to enhance the oxygen uptake of strain from molecular level and to solve the problem of oxygen limitation in process of fermentation. The carbon monoxide difference spectra analysis of Vitreoscilla hemoglobin (VHb) showed that vgb could be successfully expressed in VG1 (pTU14), and this expression was under the regulation of dissolved oxygen (DO). The higher amounts of VHb could be got correspond to the lower level of DO. Because of the introduction of vgb, cell growth and PHB accumulation of VG1 (pTU14) were all strongly promoted during the process of batch culture.

[Effect of Ce3+ on reactive oxygen species in cells]

The effect of Ce3+ on the content of (reactive oxygen species ROS) in hepatocytes and V79 cells was studied with microfluorometry. The results showed that Ce3+ could enhance the concentration of ROS in hepatocytes in high dose and reduce the concentration of ROS in low dose. These results suggested that Ce3+ might decrease the damage of lipid peroxidation and DNA in low dose and might increase the damage of lipid peroxidaion and DNA in high dose.

Coinfection of enteric Helicobacter spp. and Campylobacter spp. in cats

During a 6-year period, 64 of 227 commercially reared cats had microaerobic bacteria isolated from their feces. All the isolates were initially identified as Campylobacter-like organisms based on biochemical and phenotypic characteristics. DNA extractions from 51 of these isolates were subjected to PCR using primers specific for Helicobacter spp. and Campylobacter spp. Of the isolates, 92% (47 of 51 isolates) were positive for Campylobacter spp., 41% (21 of 51 isolates) were positive for Helicobacter spp., 33% (17 of 51 isolates) were positive for both genera, 59% (30 of 51 isolates) were positive only for Campylobacter spp., and 8% (4 of 51) were positive only for Helicobacter spp. Sixteen of the 47 Campylobacter-positive cultures were positive for more than one Campylobacter spp. Based on a species-specific PCR assay, 83% of the isolates were identified as Campylobacter helveticus, 47% of the isolates were identified as Campylobacter upsaliensis, and 6% of the isolates were classified as Campylobacter jejuni. The 1.2-kb PCR products of the 16S rRNA genes of 19 Helicobacter species isolates were subjected to restriction fragment length polymorphism (RFLP) analysis. Of the five different RFLP patterns obtained, two clustered with Helicobacter ("Flexispira") taxon 8, one clustered with Helicobacter bilis, one clustered with Helicobacter canis, and the remaining pattern was closely related to a novel Helicobacter sp. strain isolated from a woodchuck. The sequence data for the 16S rRNA genes of 10 Helicobacter spp. validated the RFLP-based identification of these isolates. This study demonstrated that biochemical and phenotypic characteristics of microaerobic organisms in cat feces were insufficient to characterize mixed Helicobacter and Campylobacter infections. Molecular structure-based diagnostics using genus- and species-specific PCR, RFLP analysis, and 16S rRNA sequence analysis enabled the identification of multiple microaerobic species in individual animals. The clinical relevance of enteric Helicobacter and Campylobacter coinfection in cats will require further studies.

[Determination of nickel in artificial cream by flame atomic absorption spectrometry]

This paper describes a new method for the determination of nickel in artificial cream by flame atomic absorption spectrometry. Compared with the others, the process of sample treatment by HNO3-H2SO4 is simple, and the operation is easy. The results show that the method offers good precision and accuracy. The relative standard deviation is 3.04% and the rate of recovery is 97.7%.

[Relationship of vitamin D receptor polymorphism with breast cancer]

OBJECTIVE

To detect the association between vitamin D receptor polymorphism and breast cancer.

METHODS

Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) method was used. Two restriction fragment length polymorphisms in the 3'region of vitamin D receptor (VDR) gene, Taq I and Apa I, were tested for association with breast cancer risk in 86 females with breast cancer and 134 healthy female controls.

RESULTS

Allele frequencies of the 3'Taq I polymorphism showed a significant association (P=0.0004, OR:5.39,CI:1.81-17.20). The further study of genotype found the association of Tt, tt with breast cancer. The haplotype analysis of Apa I and Taq I showed a linkage disequilibrium between t-allele and A-allele. The frequency of tA haplotype was higher in breast cancer patients than in controls (P=0.001), indicating that tA haplotype is associated with breast cancer. The alleles and haplotype of the two loci had not any difference among the clinical subgroups.

CONCLUSION

There is association between vitamin D receptor polymorphism and breast cancer.

[The prevalence of renal artery stenosis in patients with coronary artery disease]

OBJECTIVE

To understand the prevalence of renal artery stenosis(RAS) in patients with coronary artery disease(CAD) and the relations among coronary artery disease, renal artery stenosis, hypertension and renal insufficiency.

METHODS

280 patients with coronary artery disease or suspected coronary disease were carried out renal artery angiography after coronary angiography over 1 year period.

RESULTS

Of the total patient cohort, 43(15.3%) had significant RAS (> or = 50%), 3(1.0%) were obstructed and 14 (5.0%) were bilateral. 36 (19.1%) were diagnosed as having significant RAS among 188 CAD patients. 7 patients with significant RAS were found among 92 patients without significant coronary artery stenosis, all of them were found in the group of 22 patients with mild coronary artery atheroscloresis. The prevalence of significant RAS was 19.6% and 7.9% as referred to with or without hypertension, P < 0.05. 10 patients (55.6%) had significant RAS in 18 patients with mild renal insufficiency as compared to 33 patients (12.6%) had significant RAS in 262 patients with normal renal function, P < 0.05. In the subgroup of CAD, the prevalence of significant RAS were 15.3%, 17.1%, 25.4% in single vessel disease, two vessel disease and triple vessel disease patients, P < 0.05. 35 patients (81.4%) had hypertension among these 43 patients with RAS with 24 (56.0%) patient's blood pressure difficult to control.

CONCLUSIONS

RAS is a frequent finding in patients with CAD, especially in triple vessel disease patients. Hypertension is closely related to RAS, it should be the risk factor of RAS, and can be the clinical manifestation of RAS. CAD patients with renal insufficiency but without history of chronic glomerulonephritis may indicate RAS.

A mixed-valence manganese(III)-manganese(IV) di-mu-oxo complex, [(cyclam)MnO]2(ClO4)2(NO3)

The title dinuclear di-mu-oxo-bis[(1,4,8,11-tetraazacyclotetradecane-kappa(4)N)manganese(III,IV)] diperchlorate nitrate complex, [Mn(2)O(2)(C(10)H(24)N(4))(2)](ClO(4))(2)(NO(3)) or [(cyclam)MnO](2)(ClO(4))(2)(NO(3)), was self-assembled by the reaction of Mn(2+) with 1,4,8,11-tetraazacyclotetradecane in aqueous media. The structure of this compound consists of a centrosymmetric binuclear [(cyclam)MnO](3+) unit, two perchlorate anions and one nitrate anion. While the low-temperature electron paramagnetic resonance spectra show a typical 16-line signal for a di-mu-oxo Mn(III)/Mn(IV) dimer, the magnetic susceptibility studies also confirm a characteristic antiferromagnetic coupling between the electronic spins of the Mn(IV) and Mn(III) ions.

[Determination of trace as in health-giving drink by AA-670 atomic absorption spectrophotometry attached VA-90 atomization]

A new method has been developed for the determination of trace metal As in health-giving drink by AA-670 atomic absorption spectrophotometry attached VA-90 atomization. The method is convenient to determine element in water. The results show that the method has good precision and accuracy. The detection limit is 2 ng.L-1 for As. The relative standard deviation is 5.4%-6.1%, and the rates of recovery is 87.5%-115%. This method has been applied to the determination of health-giving drink with satisfactory results.

Resolution of structural isomers of sialylated oligosaccharides by capillary electrophoresis

The resolution of structural isomers in mixtures of oligosaccharides is often challenging. Capillary electrophoresis was employed to separate three sets of structural isomers of sialylated oligosaccharides found in human milk and bovine colostrum. Different running buffers were necessary to achieve optimal baseline resolution. To resolve 3'- and 6'-sialyllactoses, 0.2 M aqueous sodium phosphate containing 40% methanol as an organic modifier was used as a running buffer. To resolve 3'- and 6'-sialyllactosamines, 0.4 M aqueous sodium phosphate without organic modifier was used. Baseline resolution of sialyllacto-N-tetraose-a and -b and sialyllacto-N-neotetraose-c was achieved with a 0.4 M Tris-HCl buffer containing 250 mM sodium dodecyl sulfate and 10% methanol as the organic modifier. Thus, each of these sets of structural isomers of sialylated oligosaccharides required a unique running buffer with respect to buffer type, concentration, pH, presence of organic modifiers, and surfactants. Similar electrophoresis conditions may be useful for resolving and analyzing other structural isomers of acidic oligosaccharides by capillary electrophoresis.

[Experimental research of laser-induced collaterals in retinal vein occlusion]

OBJECTIVE

To evaluate the feasibility and safety of establishing chorioretinal venous anastomosis in rabbit eyes with a model of branch retinal vein occlusion

METHODS

By using laser photocoagulation, a chorioretinal venous anastomosis was created in rabbit eyes in which a branch retinal vein occlusion had previously been established photochemically. A similar attempt to create an anastomosis was made in the control eyes in which no branch vein occlusion was present.

RESULTS

In the 21 eyes with the model of branch retinal vein occlusion, a chorioretinal venous anastomosis formed in 4 eyes within 3 to 5 weeks. In the control eyes, an anastomosis in one eye presented by 5 weeks, during follow-up of 2 to 5 months. The hemorrhage in choroid, retina and vitreous associated with laser photocoagulation were absorbed within 3 weeks, and no other severe complications were found.

CONCLUSIONS

Chorioretinal venous anastomosis can be created by using laser photocoagulation. This technique is relatively safe. However, to improve the rate of successfully creating an anastomosis, more research work needs to be performed.

[The difference of intracellular cytokines produced by different lymphocyte subsets of cord blood and adult peripheral blood]

OBJECTIVE

To explore the difference of intracellular cytokines between cord blood and adult peripheral blood and elucidate its significance for GVHD.

METHOD

Different lymphocyte subsets were categorized in cord and adult peripheral blood by monoclonal antibodies with 3 color fluorescence using flow cytometry. The IL-2, TNF-alpha and IFN-gamma produced by various lymphocyte subsets were compared between the two groups.

RESULT

(1) In cord blood, dominant T cells were CD(4)(+)CD(45RA)(+), while the major T cells were both CD(4)(+)CD(45RO)(+) and CD(8)(+)CD(45RO)(+) in adult peripheral blood. (2) The quantities of IL-2, TNF-alpha and IFN-gamma produced by cord blood lymphocytes were lower than that of adult peripheral blood lymphocytes. Moreover, the majority of cells that produced cytokines in the cord blood were CD(4)(+)CD(45RA)(+), but in adult peripheral blood were mainly CD(4)(+)CD(45RO)(+) and CD(8)(+)CD(45RO)(+).

CONCLUSION

As compared with adult peripheral blood, the cord blood not only possessed different proportion of lymphocyte subsets, but also significant low level of cytokines. The differences of various lymphocyte subset proportions and lower level of cytokines in cord blood probably related to the lower incidence of GVHD in cord blood stem cell transplantation.

[Effect of rice canopy structural changes on bidirectional reflectance]

The study of vegetation bidirectional reflectance is useful for remote sensing data interpretation. Vegetation canopies information such as leaf area index, mean leaf inclination, mean plant height, and coverage, can be inverted from vegetation bidirectional reflectance. This paper discussed the dynamics of vegetation canopies reflectance with vegetation canopy structures by measuring rice canopy structure and bidirectional reflectance at 26, 35, 41, 49, 62, 67 and 86 days after transplanting. It is concluded that the sensitivity of vegetation canopies to directional reflectance variations varied with canopy structures, and hence, through bidirectional reflectance, more information about canopy structure can be know.