Adalimumab significantly reduces inflammation and serum DKK-1 level but increases fatty deposition in lumbar spine in active ankylosing spondylitis

AIM

To investigate whether adalimumab is effective for active ankylosing spondylitis (AS) patients and whether it has an impact on the formation of fatty deposition lesions (FDL) and serum Dickkopf homolog 1 (Dkk-1) level in AS patients.

METHOD

This was a randomized, double-blind, placebo-controlled study. Active AS patients received 40 mg adalimumab (n = 26) or placebo (n = 20) every other week during an initial 12-week double-blind period, and all switched to adalimumab treatment for another 12 weeks. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Function Index (BASFI), C-reactive protein (CRP), Ankylosing Spondylitis Disease Activity Scores (ASDAS) and serum DKK-1 levels were measured and magnetic resonance imaging (MRI) of both the lumbar spine and sacroiliac joints were obtained at baseline, week 12 and week 24. Spinal and sacroiliac joint inflammations were evaluated using the Spondyloarthritis Research Consortium of Canada (SPARCC) MRI index, and FDL were assessed in a dichotomous manner.

RESULTS

Obvious improvements in clinical assessments (BASDAI, BASFI, CRP and ASDAS reduced, all P < 0.05), as well as MRI inflammation measurements (both lumbar spine and sacroiliac joints SPARCC scores decreased, all P < 0.05) were shown in active AS patients treated by adalimumab for 12 weeks, but FDL in the lumbar spine seen by MRI increased significantly (P < 0.05) accompanied by decrease of serum DKK-1 levels (P < 0.05), while FDL remained stable after the treatment of placebo in AS patients.

CONCLUSION

Our study found that adalimumab was highly effective in reducing inflammation in active AS patients, but it was accompanied by the formation of FDL in the lumbar spine and decrease in serum DKK-1 levels.

Identification of Th1 epitopes within molecules from the lung-stage schistosomulum of Schistosoma japonicum by combining prediction analysis of the transcriptome with experimental validation

The lung-stage schistosomulum has been regarded as the main target of protective immunity induced by radiation-attenuated vaccines (RAV) in the mouse model of schistosomiasis, and immune mechanisms mediated by the CD4+ Th1 response play a major role in the RAV model. To identify Th1 epitopes rapidly within molecules from the lung schistosomulum of Schistosoma japonicum, in the present study we analyzed transcriptome data from normal and radiation-attenuated lung schistosomula of S. japonicum and Schistosoma mansoni. We selected six genes with high levels of expression of their transcripts as sample sequences from the lung schistosomula. From these six sequences, by using different algorithms, we predicted six promiscuous Th cell epitopes that are capable of binding to both murine and human MHC class II molecules. To validate our in silico prediction experimentally, first, the gene expressions of the six sequences in day 3 lung-stage schistosomula were assessed using reverse-transcription PCR (polymerase chain reaction) analysis. The result showed that all six sequences predicted can be expressed in normal day 3 schistosomula. Second, we measured the direct binding of the four peptides predicted above to APCs (Antigen Presenting Cells) from the BALB/c mouse strain using a fluorometric method, and found that the four peptides could bind to both I-Ad and I-Ed molecules of the mice. Finally, the proliferation and profiles of cytokine production by spleen lymphocytes from the BALB/c mice immunized with the six predicted peptides were detected in vitro using modified MTT (Methyl Thiazolyl Tetrazolium), and flow cytometry methods, respectively. The results showed that three of the six predicted peptides could induce a recall CD4+ Th1 response in vitro. These results demonstrate that potential Th1-type epitopes can be identified rapidly by a combination of in silico analysis of transcriptomes of lung-stage schistosomula with experimental validation.

A study on the association of serum 1,5-anhydroglucitol levels and the hyperglycaemic excursions as measured by continuous glucose monitoring system among people with type 2 diabetes in China

BACKGROUND

Blood glucose excursion is an important component of the glycaemic burden, but there are no indexes that can directly reflect them. The aim was to evaluate the values and significance of serum 1,5-anhydroglucitol (1,5-AG) in people with type 2 diabetes mellitus in China and to elucidate the relationship between 1,5-AG and traditional indexes of glycaemic excursions by continuous glucose monitoring.

METHODS

A total of 576 healthy adults and 292 patients were included, and their 1,5-AG, fasting blood glucose and postprandial blood glucose and glycated haemoglobin were measured. For the 34 patients, their mean blood glucose, standard deviation of blood glucose, mean amplitude of glucose excursion, mean of daily differences, low blood glucose M-value index and the area under the curve for blood glucose above 180 mg/dL were calculated by use of a continuous glucose monitoring system.

RESULTS

Serum levels of 1,5-AG among healthy adults were 28.44 ± 8.76 µg/mL with a significant gender bias rather than age bias. The 1,5-AG levels in people with type 2 diabetes mellitus were 4.57 ± 3.71 µg/mL, which were lower than those seen in the healthy adults. There was a correlation between 1,5-AG and glycated haemoglobin, fasting blood glucose, and postprandial blood glucose (r = -0.251, -0.195 and -0.349, respectively; all had p < 0.05). The continuous glucose monitoring system demonstrated that 1,5-AG presents a negative correlation with mean blood glucose, standard deviation of blood glucose, mean amplitude of glucose excursion and mean of daily differences for 7 days and with the area under the curve for blood glucose above 180 mg/dL on the third, fourth and seventh days.

CONCLUSIONS

1,5-AG may serve as a marker of hyperglycaemia and 7-day hyperglycaemic excursions as well as being a useful adjunct to glycated haemoglobin for blood glucose monitoring in patients with diabetes.

First Report of Ziziphus jujuba Wilt Caused by Fusarium oxysporum in China

Chinese jujube (Ziziphus jujuba Mill.) is widely planted in Xinjiang Province of China for fruit and as an effective herbal remedy. Wilt symptoms were observed on field-grown Z. jujuba during the spring and fall of 2010 and 2011. Diseased plants exhibited symptoms including wilted leaves, stunted growth, extensive brown discoloration on stems, and eventually death. In severe cases, approximately 60% of the plants in the field died. Repeated isolations from discolored stem vascular tissues were made on potato dextrose agar (PDA) after disinfestation in 1% HgCl₂ for 1 min and dipping in 70% ethanol for 10 s. Petri dishes were then incubated in complete darkness at 26°C for 7 days. All colonies on PDA had pale pink-salmon-colored mycelia. Macroconidia were mostly three to five septate, slightly curved, and ranged from 2.9 to 11.9 × 29.5 to 45 μm. Microconidia were abundant, generally single celled, oval to kidney shaped, and ranged from 2.5 to 5 × 7.5 to 11.5 μm in false heads on short monophialides. Chlamydospores were single or in pairs and profusely distributed. These characteristics were similar to those of Fusarium oxysporum (2). The internal transcribed spacer (ITS) rDNA region was amplified with primers ITS1/ITS4 and sequenced (1). BLASTn analysis of the sequence (GenBank Accession No. JQ039331) showed a 99% homology with several isolates of F. oxysporum in the GenBank database. Pathogenicity tests were conducted on healthy, 2-month-old seedlings and 1-month-old rooted cuttings of Z. jujuba under greenhouse conditions. Plants were inoculated with sterilized mixtures of wheat and barley seeds (1:1) that were incubated in a F. oxysporum isolate spore suspension (1 × 10⁷ conidia/ml) at 25°C for 7 to 10 days. The seeds (3 g per plant) were placed around the collar of each healthy plant under the soil surface and incubated at 25 to 28°C in a greenhouse. Control plants were sown in sterile soil without inoculated seeds. In 3 weeks, inoculated plants developed leaf wilt and chlorosis, stunted growth, brown discolored vascular tissue on stems, and finally died, which is similar to that observed in the field. F. oxysporum was reisolated from the stems of diseased plants, confirming Koch's postulates. Control seedlings were symptom free. F. oxysporum has been known to cause wilt disease on cotton and tomato in Xinjiang Province (3). However, to our knowledge, this is the first report of a natural occurrence of Chinese jujube wilt disease on commercial fields caused by F. oxysporum in China. References: (1) G. M. Arruda et al. Plant Pathol. 54:53, 2005. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Ames, IA, 2006. (3) F. X. Tian et al. Acta Phytopathol. Sin. 11:27, 1981.

Optimization of factors affecting Agrobacterium-mediated transformation of Micro-Tom tomatoes

Micro-Tom is the smallest known variety of tomatoes. An orthogonal experimental design L(16) (4(5)) was used to optimize Agrobacterium-mediated transformation of cotyledon explants of Lycopersicon esculentum cv. Micro-Tom. Four parameters were investigated to determine their effect on transformation frequency: the concentration of bacterial suspension, time of dip in bacterial suspension, co-cultivation time, and concentration of carbenicillin. We also examined the effect of these parameters on contamination rate, necrosis rate, mortality, cut-surface browning rate, and undamaged explant rate. Both the bacterial and carbenicillin concentrations had a significant influence on the rate of infected explants. The time of co-cultivation also had a significant influence on the transformation parameters. The optimal transformation protocol consisted of an Agrobacterium suspension of 0.5 × 10(8) cells/mL (OD(600) = 0.5) and an infection time of 5 min, one day of co-cultivation and 500 mg/L carbenicillin. Under these conditions, the transformation efficiency of the shoots reached 5.1%; the mean transformation frequency was 3.9% (N = 838).

Detection of placenta elasticity modulus by quantitative real-time shear wave imaging

OBJECTIVE

To explore the clinical values in detecting the placental elastic modulus using real-time quantitative shear wave elasticity imaging.

METHODS

A total of 30 women in the late pregnancy stage without complications and having normal, single pregnancies, as well as normal fetal growth, amniotic fluid index, and anterior placenta were selected. A real-time elasticity imaging shear wave ultrasonic diagnostic apparatus was used to randomly select regions of interest at the central and edge of the placenta. The elastography imaging mode was launched to measure the elasticity of the elastic modulus of these placental parts. A total of 15 measured values were obtained at the placental center and edge for each pregnancy case. Umbilical artery and uterine artery pulsatility index (PI) values for 18 cases were also randomly measured.

RESULTS

The average value of 30 placental edges of the elastic modulus (n = 15) was (7.60 +/- 1.71) kPa. The average value of the 30 placental central elastic modulus (n = 15 ) was (7.84 +/- 1.68) kPa. No significant difference was observed between placenta central and edge elastic modulus. The PI mean value of umbilical artery in 18 cases was 0.94, whereas the average PI values of the uterine artery was 0.83. No linear correlation was found among the elastic modulus, the placental uterine artery PI values, and the umbilical artery PI values (p > 0.05).

CONCLUSION

No difference between the placental center of normal pregnancies and the edge of the elastic modulus was detected. The elastic modulus of the placenta could be obtained in the best position. The placenta varied greatly between elastic modulus. No correlation was found between the placental elastic modulus, the uterine artery, and umbilical artery PI values. Real-time shear wave elasticity imaging technology can provide morphological evidence of placental function, which may emerge as a new clinical assessment approach.

Adsorption of copper(II) onto sewage sludge-derived materials via microwave irradiation

The materials with adsorbent properties were produced from urban sewage sludge by two different procedures via microwave irradiation: (1) by one single pyrolysis stage (SC); (2) by chemical activation with ZnCl(2) (SZ). The BET, SEM and FT-IR have been used to evaluate the pore structural parameters and surface chemistry of the adsorbents, respectively. Subsequently they were used for adsorption of Cu(II) from aqueous solutions. The effects of various experimental parameters, such as pH, temperature were investigated in a batch-adsorption technique. The results showed that the adsorption of Cu(II) was maximal at pH 5.0. The kinetic study demonstrated that the adsorption process was followed the second-order kinetic equation. The experimental adsorption isotherm data were well fitted with Langmuir model and the maximum adsorption capacity of Cu(II) were found to be 3.88 and 10.56 mg/g for SC and SZ, respectively, in the solution of pH 5.0. Thermodynamic parameters such as changes in the enthalpy (ΔH(0)), entropy (ΔS(0)) and free energy (ΔG(0)) indicate that Cu(II) adsorption onto SC and SZ is an endothermic and spontaneous process in nature at 15-45°C. These results indicate that the sewage sludge-derived material via microwave induced ZnCl(2) activation is an effective and alternative adsorbent for the removal of Cu(II) from aqueous solution.

A preliminary study on the occurrence and behavior of carbamazepine (CBZ) in aquatic environment of Yangtze River Delta, China

The occurrence and behavior of carbamazepine (CBZ) was investigated in aquatic environment of Yangtze River Delta, East China. The water samples were enriched by solid-phase extraction and analyzed by high-performance liquid chromatography with diode array detector. The validation of the analytical method included linearity (0.1-1 mg/L), recovery studies, and determination of limits of quantification. Limits of quantification of CBZ in various aquatic samples were in the range of 0.1-0.2 μg/L. CBZ was detected in the Tongji University Intramural River, the Huangpu River, and the Suzhou River with the highest concentration of 1,090 ng/L, but not detected in the Nanhengyin River and the Caojia River. In sewage water samples, CBZ was not detected in one of the sewage treatment plants (STPs) but was detected in the raw influents and effluents at the other three selected STPs in Shanghai, with the concentrations ranging from 230 to 1,110 ng/L. CBZ was not completely eliminated after secondary treatment (with the active sludge process).

Algal-derived organic matter as precursors of disinfection by-products and mutagens upon chlorination

Algal-derived organic materials (including algal cells, hydrophilic and hydrophobic proteins) from Chlamydomonas sp. (a common green alga in local reservoirs), were chlorinated in the laboratory (20 °C, pH 7, Cl(2)/DOC ratio of 20 mg Cl(2) mg(-1)). Levels of disinfection by-products and mutagenicity (via Salmonella T100 mutation assay, -S9) over 2 h of chlorination time were determined. The hydrophilic proteins were more effective precursors of chloroform (35.9 μmol L(-1) at 120 min), 35 times greater than that from the hydrophobic proteins; whereas the hydrophobic proteins were more potent precursors of direct-acting mutagens (maximum level of 50.1 rev μL(-1) at 30 s) than the hydrophilic proteins (maximum level of 3.38 rev μL(-1) at 60 min). The mutagenicity of the chlorinated solutions generally reached a peak level shortly after chlorination and then declined afterwards, a pattern different from that of chloroform generation. The results indicate that algal hydrophilic proteins, containing low aromaticity and difficult to be removed via coagulation/flocculation, are important chloroform precursors. It is also suggested that hydrophobic organic intermediates with low molecular weight formed during chlorination may serve as the direct-acting mutagens.

In vitro behavior of MC3T3-E1 preosteoblast with different annealing temperature titania nanotubes

OBJECTIVE

Titanium oxide nanotube layers by anodization have excellent potential for dental implants because of good bone cell promotion. It is necessary to evaluate osteoblast behavior on different annealing temperature titania nanotubes for actual implant designs.

MATERIALS AND METHODS

 Scanning Electron Microscopy, X-Ray polycrystalline Diffractometer (XRD), X-ray photoelectron Spectroscope, and Atomic Force Microscopy (AFM) were used to characterize the different annealing temperature titania nanotubes. Confocal laser scanning microscopy, MTT, and Alizarin Red-S staining were used to evaluate the MC3T3-E1 preosteoblast behavior on different annealing temperature nanotubes.

RESULTS

 The tubular morphology was constant when annealed at 450°C and 550°C, but collapsed when annealed at 650°C. XRD exhibited the crystal form of nanotubes after formation (amorphous), after annealing at 450°C (anatase), and after annealing at 550°C (anatase/rutile). Annealing led to the complete loss of fluorine on nanotubes at 550°C. Average surface roughness of different annealing temperature nanotubes showed no difference by AFM analysis. The proliferation and mineralization of preostoblasts cultured on anatase or anatase/rutile nanotube layers were shown to be significantly higher than smooth, amorphous nanotube layers.

CONCLUSION

 Annealing can change the crystal form and composition of nanotubes. The nanotubes after annealing can promote osteoblast proliferation and mineralization in vitro.

Production of dairy goat embryos, by nuclear transfer, transgenic for human acid beta-glucosidase

Expression of recombinant human lysosomal acid beta-glucosidase (hGCase) by a transgenic animal bioreactor, using somatic cell nuclear transfer (SCNT), would decrease the cost of producing this product. The objective was to establish an effective procedure to prepare hGCase transgenic donor cells and nuclear transfer (NT) embryos to produce hGCase protein in the Saanen dairy goat mammary gland. A mammary-specific expression vector for hGCase was constructed and transfected into HC-11 mammary epithelial cells for bioactivity analysis in vitro; mRNA transcripts and hGCase protein were correctly expressed in transfected HC-11 cells. The hGCase gene was then introduced into fetal fibroblasts (from dairy goats) to prepare competent transgenic donor cells. Transgenic fibroblast clones from a single round of transfection were reliably isolated by 96-well cell culture plates and screened with PCR amplification and chromosomal counting (66.8%). Dairy goat cloned embryos were produced from these hGCase fetal cells by SCNT, the hGCase transgene was successfully detected in these embryos, and there were similar rates (P>0.05) of fusion (83.3% vs. 77.8%), cleavage (89.1% vs. 90.9%), and development to the morula/blastocyst stages (36.4% vs. 38.9%) between NT embryos using transgenic fetal fibroblasts and non-transfected control cells. Moreover, 98 well-developed reconstructed embryos derived from transgenic cells were transferred to 16 recipients; pregnancy was confirmed at 40 d in two goats. Therefore, we achieved functional expression of hGCase in mammary gland cells and normal development to Day 40 of cloned embryos carrying the hGCase gene.

Automatic control of mechanical forces acting on cell biomembranes using a vision-guided microrobotic system in computer microscopy

A prototype for automatic control of mechanical forces acting on cell biomembranes is proposed in this paper. This prototype consists of vision-guided position control of the holder and micro-force sensor, automatic mechanical property characterization of cell biomembranes and automatic control of mechanical forces acting on cell biomembranes. A template-free calibration method and autofocusing of multiple objects are introduced in the vision-guided position control to minimize external biological contamination and position the cell, holder and micro-force sensor into the same focal plane, respectively. A third-order polynomial modified from biomembrane point-load model describing the relationship between the measured mechanical force and the deformations of biomembranes is proposed. This simplified model is easily identified and inversed to facilitate the automatic control of mechanical forces. Experimental results based on zebrafish embryos demonstrate the feasibility of the proposed prototype.

Self-calibration method for vision-guided cell micromanipulation systems

A new self-calibration method for a piezoelectric actuator-based vision-guided cell micromanipulation system is proposed. This method consolidates all the system parameters' uncertainties into a matrix instead of classifying into intrinsic and extrinsic. The position difference of the micromanipulator tip in the image plane between the measured and estimated output which is based on estimations of relevant parameters is assumed to be caused by the matrix. This matrix is estimated by means of collecting several pairs of known input and the corresponding output differences. Matrix standard deviation and gray-value based matching are applied to identify the output differences. Biological contamination is reduced since a calibration template is not required. This self-calibration is particularly suitable for cell micromanipulation systems where the micromanipulator is frequently dismounted and mounted.

Simultaneous determination of 8 fluoroquinolone antibiotics in sewage treatment plants by solid-phase extraction and liquid chromatography with fluorescence detection

Fluoroquinolones (FQs) are among the most important antibiotics used in human and veterinary medicines. A simple and effective analytical method based on reversed-phased liquid chromatography with fluorescence was developed and validated for the simultaneous determination of eight FQs in wastewater at trace level. Aqueous samples were extracted using Anpel(TM) MEP cartridges where they were subsequently eluted by formic acid in methanol. The aqueous extracts were analyzed by gradient elution Liquid Chromatography with Fluorescence Detection (LC-FLD), whose mobile phase was composed of acetonitrile and 10 mM tetrabutyl ammonium bromide (TBAB). The limits of detection (LOD) and the relative standard deviation (RSD) were as low as 0.11-1.06 microg/L and 2-5%, respectively. The presented method was successfully applied to quantify FQs in the influent and effluent of several typical Sewage Treatment Plants (STPs) in Shanghai. For the extraction of 100 mL influent and 500 mL effluent sewage water samples, recoveries obtained were between 79-109% and 80%-105%, respectively. 7 FQs were occurred and identified in the STPs with the concentrations varying from 7 ng/L to 1 microg/L. Norfloxacin, ciprofloxacin and lomefloxacin were the most frequently detected antibiotics occurring in the wastewaters. The analytical procedure developed may be used for more in-depth studies on the occurrences and the fate of these commonly used pharmaceuticals in the sewage treatment plants and in the aquatic environment.

Phytohemagglutinin improves efficiency of electrofusing mammary gland epithelial cells into oocytes in goats

The objective was to investigate the effect of phytohemagglutinin (PHA) on the fusion of mammary gland epithelial (MGE) cells into enucleated oocytes in goats. The toxicity of PHA was evaluated by testing its effect on the development of parthenogenetic caprine oocytes. The effective dose and duration of PHA treatment (100 microg/mL, 20 min incubation) was selected and used to compare fusion efficiency and embryo development following nuclear transfer. Two electrofusion protocols, chamber fusion (CF) and pressurized microelectrode fusion (pMEF), were also compared, when couplets were treated with and without PHA (100 microg/mL, 20 min). Fusion rate of couplets increased from 52.8 to 74.0% for the CF protocol (P<0.05), but was not significantly different for the pMEF protocol (72.7% vs. 78.1%) after PHA treatment. There were no significant differences between treated group and control in rates of subsequent cleavage or blastocyst development. Following transfer of the cloned blastocysts derived from the PHA-treated group and the control group into synchronized recipients, pregnancy rates (Day 30) were not significantly different between treated group and control (28.6% vs. 25.0%). However, all recipients aborted within 120d, microsatellite DNA analyses confirmed that the aborted fetuses were genetically identical to the donor goat. In conclusion, the fusion rate of caprine MGE cell couplets was improved by pre-incubating couplets in medium containing 100 microg/mL PHA prior to electrical pulsing, and embryos derived from PHA treatment established early pregnancies.

Characterization of phytoene synthase 1 gene (Psy1) located on common wheat chromosome 7A and development of a functional marker

Phytoene synthase (Psy), a critical enzyme in the carotenoid biosynthetic pathway, demonstrated high association with the yellow pigment (YP) content in wheat grain. Characterization of Psy genes and the development of functional markers for them are of importance for marker-assisted selection in wheat breeding. In this study, the full-length genomic DNA sequence of a Psy gene (Psy-A1) located on chromosome 7A, was characterized by in silico cloning and experimental validation. The cloned Psy-A1 comprises six exons and five introns, 4,175 bp in total, and an ORF of 1,284 bp. A co-dominant marker, YP7A, was developed based on polymorphisms of two haplotypes of Psy-A1, yielding 194 and 231-bp fragments in cultivars with high and low YP content, respectively. The marker YP7A was mapped on chromosome 7AL using an RIL population from cross PH82-2/Neixing 188, and a set of Chinese Spring nullisomic-tetrasomic lines and ditelosomic line 7AS. Psy-A1, co-segregating with the STS marker YP7A, was linked to SSR marker Xwmc809 on chromosome 7AL with a genetic distance of 5.8 cM, and explained 20-28% of the phenotypic variance for YP content across three environments. A total of 217 Chinese wheat cultivars and advanced lines were used to validate the association between the polymorphic band pattern and grain YP content. The results showed that the functional marker YP7A was closely related to grain YP content and, therefore, could be used in wheat breeding programs targeting of YP content for various wheat-based products.

Treatment of succinonitrile wastewater by immobilized high efficiency microorganism strains

Using succinonitrile as a sole source of carbon and nitrogen, two bacterium strains named as J-1-3 and J-13-1 were isolated and screened out from the treatment facilities of Shanghai petrochemical wastewater treatment plant treating acrylic fiber production wastewater. The optimal growth conditions of the two strains in the degradation of succinonitrile with varied initial concentrations were determined through flask tests as follows: temperature 30 degrees C, shaker rotary speed of 250 r/min, inoculum percentage 0.1%, and initial pH 6. Results indicate that the two strains, especially J-13-1, exhibited a high efficiency for succinonitrile degradation. Thereafter, the bacterium strains were immobilized separately by sodium alginate and polyvinyl alcohol 1750 +/- 50, and applied to succinonitrile degradation again. Results show that in a very broad range of the initial succinonitrile concentration, i.e., 30-5,000 mg/L, the sodium alginate immobilized grains could degrade more than 80% of succinonitrile after 24 h under the experimental conditions of 30 degrees C, pH 6.5, and shaker rotary speed of 250 r/min. However, the polyvinyl alcohol immobilized grains tended to inflate and break down due to a weak mechanical strength.

Expression of human BK ion channels in Sf9 cells, their purification using metal affinity chromatography, and functional reconstitution into planar lipid bilayers

This report describes a procedure for purification of large conductance calcium-activated potassium (BK, maxi-K) channels using immobilised metal affinity chromatography (IMAC) under non-denaturing conditions. An amino-terminal histidine fusion tag was added to hSlo, the human BK channel, and expressed in Sf9 insect cells. Following IMAC purification and production of proteoliposomes, protein function was assessed electrophysiologically in planar bilayer lipid membranes. Single channel openings had conductances of 250-300 pS and were inhibited by paxilline, demonstrating that the BK channels remained functional following IMAC purification. This method to obtain functional human ion channels will be useful in assays to screen potential pharmaceuticals.

Recombinant human voltage-gated skeletal muscle sodium channels are pharmacologically functional in planar lipid bilayers

Human voltage-gated sodium ion channels are major sites of action for drugs and toxins that modulate cellular excitability, and are therefore key molecular targets for ion channel research, high throughput screening for new drugs, and toxin detection. Protein suitable for these applications must be produced in a functionally active form. We report the successful use of ion metal affinity chromatography (IMAC) to purify C-terminal polyhistidine tagged human skeletal muscle voltage-gated sodium (hSkM1-HT) channels from Sf9 insect cells; hSkM1 channels were pharmacologically functional when reconstituted into liposomes and incorporated into planar bilayer lipid membranes. hSkM1-HT single channel currents activated by veratridine had a conductance of 21 pS and those activated by brevetoxin, 16 pS. Channel activity was inhibited by tetrodotoxin and saxitoxin. This protein is suitable for the development of biosensor and high throughput screening technologies.

Genotyping of human cystic echinococcosis in Xinjiang, PR China

The Xinjiang Uygur Autonomous Region, multi-ethnic province in northwestern China, is one of the most important foci of human cystic echinococcosis (CE) in the world. Two Echinococcus granulosus genotypes (G1 and G6) are known to infect the intermediate hosts in this area but, to date, the source of the human infection remains unclear. The current study aimed to genetically analyse 67 hydatid cysts removed from 47 CE patients for which epidemiological, clinical and serological data were also recorded. Mitochondrial cox 1 gene sequencing suggested that the E. granulosus G1 genotype is the major source of infection (45/47 CE patients). Nevertheless, for the first time in China, 2 patients were found with hydatid cysts of the G6 genotype. In addition, 45 E. granulosus gravid tapeworms, isolated from 13 dogs, were genotyped. The majority of adult worms (42/45) exhibited the G1 genotype, whereas 3 adult tapeworms with the G6 genotype were found in one dog, that also harboured E. granulosus tapeworms of the G1 genotype. This sympatric occurrence of G1 and G6 genotypes of E. granulosus, not only in the same area but also in the same definitive host, raises the interesting question of putative genetic recombination between these E. granulosus genotypes.

Supported bilayer lipid membranes modified with a phosphate ionophore

This article reports the electrical responses of a phosphate ionophore, the cyclic polyamine 3-decyl-1,5,8-triazacyclodecane-2,4-dione (N3-cyclic amine) incorporated into metal supported bilayer lipid membranes (s-BLM). Teflon coated silver wire was used as a support. In a potentiometric mode, the ionophore had a response that was linearly related to the logarithm of HPO4(2-) concentration and was also dependant on pH. Selectivity coefficients for other anions compared to HPO4(2-) ions, determined by the separate solution method, fell within the range 1.73 x 10(-4) to 6.38 x 10(-2).

Bicyclic and tricyclic thiophenes as protein tyrosine phosphatase 1B inhibitors

A novel pyridothiophene inhibitor of PTP1B was discovered by rational screening of phosphotyrosine mimics at high micromolar concentrations. The potency of this lead compound has been improved significantly by medicinal chemistry guided by X-ray crystallography and molecular modeling. Excellent consistency has been observed between structure-activity relationships and structural information from PTP1B-inhibitor complexes.

Identification and characterization of putative virulence genes and gene clusters in Aeromonas hydrophila PPD134/91

Aeromonas hydrophila is a gram-negative opportunistic pathogen of animals and humans. The pathogenesis of A. hydrophila is multifactorial. Genomic subtraction and markers of genomic islands (GIs) were used to identify putative virulence genes in A. hydrophila PPD134/91. Two rounds of genomic subtraction led to the identification of 22 unique DNA fragments encoding 19 putative virulence factors and seven new open reading frames, which are commonly present in the eight virulence strains examined. In addition, four GIs were found, including O-antigen, capsule, phage-associated, and type III secretion system (TTSS) gene clusters. These putative virulence genes and gene clusters were positioned on a physical map of A. hydrophila PPD134/91 to determine their genetic organization in this bacterium. Further in vivo study of insertion and deletion mutants showed that the TTSS may be one of the important virulence factors in A. hydrophila pathogenesis. Furthermore, deletions of multiple virulence factors such as S-layer, serine protease, and metalloprotease also increased the 50% lethal dose to the same level as the TTSS mutation (about 1 log) in a blue gourami infection model. This observation sheds light on the multifactorial and concerted nature of pathogenicity in A. hydrophila. The large number of putative virulence genes identified in this study will form the basis for further investigation of this emerging pathogen and help to develop effective vaccines, diagnostics, and novel therapeutics.

Detection and genetic analysis of group II capsules in Aeromonas hydrophila

The genetic organization and sequences of the group II capsule gene cluster of Aeromonas hydrophila PPD134/91 have been determined previously. The purified capsular polysaccharides can increase the ability of avirulent strain PPD35/85 to survive in naive tilapia serum but have no inhibitory effect on the adhesion of PPD134/91 to carp epithelial cells. In this study, the presence of group II capsules among 33 randomly chosen A. hydrophila strains was examined by electron microscopy and genetic analysis. Ten strains were found to produce group II capsules. A PCR detection system was developed to identify two types of group II capsules (IIA and IIB) based on their genetic organization in the region II gene clusters. Group IIA capsules in the authors' collection of A. hydrophila strains are mainly found in the O : 18 and O : 34 serogroups, while group IIB capsules are found in the O : 21 and O : 27 serogroups. The presence of group II capsules in A. hydrophila strongly correlates with the serum and phagocyte survival abilities (seven out of ten strains). The results indicate that the authors' PCR detection system can constitute a reliable assay for the classification of group II capsules in A. hydrophila.

Nitrate distribution and denitrification in the saturated zone of paddy field under rice/wheat rotation

Nitrate concentration in well water collected from the wells near farm houses was investigated in the Taihu Lake basin (TBL) of China. Nitrate-N content of the well water ranged from 0.1 to 23 mgNl(-1), and 41% exceeded the criteria (10 mg Nl(-1)). It was found that the difference in well conditions, especially the depth of the well, was the main cause of the difference in the nitrate concentration of well water, i.e. it was higher in shallow well and lower in deeper well. A recommendation was made for local farmers to drill wells deeper than 10 m in order to reduce the risk of high ingestion of nitrate-N in their drinking water. Nitrate distribution and denitrification in the saturated zone of a paddy field under rice/wheat rotation in the TBL were studied. Porous pipes were installed in triplicate at depths of 1.5, 2.0, 2.5, 3.5 and 5 m respectively to collect the soil solution samples. Results showed that nitrate was the predominant N form in soil solution of saturated zone, and it increased from 1.5 to 2.5 m depth, and decreased from 2.5 to 5 m depth. N2O captured in the soil solution was very high comparing with N2O content in air. N2O content was positively correlated with nitrate concentrations in the soil profile. These results indicate that nitrate leached into saturated zone was mainly transformed via denitrification processes. Comparing the sum of inorganic nitrogen with the total nitrogen in soil solution samples collected from those wells at the field, some soluble organic nitrogen was found about 1-2 mg N l(-1) in average.

The vibration of an artery-like tube conveying pulsatile fluid flow

A hybrid method for investigating pulsatile fluid flow in a long, thin, artery-like tube subjected to external excitations is presented. The non-linear partial differential equations governing the motion of the system, which incorporate the influence of circumferential strains, are solved by a combination of a finite element method, a finite difference method and a method of characteristics with interpolation. An initially axially stretched elastic tube conveying pulsating fluid, simply supported at both ends, is modelled to assess the effect of external harmonic excitation on the dynamic responses of the tube and the fluid flow. The results agree well with new experimental data. Comparison of the predicted results with those of a decoupled model demonstrates that it is necessary to consider the mechanism of fluid-structure interaction fully in the study of initially stretched cylindrical tubes conveying pulsatile fluid flow. An analysis of these coupling effects is presented for Womersley numbers alpha = 2.81 and 3.97 and a mean flow Reynolds number Re = 875.

Novel Aeromonas hydrophila PPD134/91 genes involved in O-antigen and capsule biosynthesis

The sequences of the O-antigen and capsule gene clusters of the virulent Aeromonas hydrophila strain PPD134/91 were determined. The O-antigen gene cluster is 17,296 bp long and comprises 17 genes. Seven pathway genes for the synthesis of rhamnose and mannose, six transferase genes, one O unit flippase gene, and one O-antigen chain length determinant gene were identified by amino acid sequence similarity. PCR and Southern blot analysis were performed to survey the distribution of these 17 genes among 11 A. hydrophila strains of different serotypes. A. hydrophila PPD134/91 might belong to serotype O:18, as represented by JCM3980; it contained all the same O-antigen genes as JCM3980 (97 to 100% similarity at the DNA and amino acid levels). The capsule gene cluster of A. hydrophila PPD134/91 is 17,562 bp long and includes 13 genes, which were assembled into three distinct regions similar to those of the group II capsule gene cluster of Escherichia coli and other bacteria. Regions I and III contained four and two capsule transport genes, respectively. Region II had five genes which were highly similar to capsule synthesis pathway genes found in other bacteria. Both the purified O-antigen and capsular polysaccharides increased the ability of the avirulent A. hydrophila strain PPD35/85 to survive in naïve tilapia serum. However, the purified surface polysaccharides had no inhibitory effect on the adhesion of A. hydrophila PPD134/91 to carp epithelial cells.

Construction and selection of the natural immune Fab antibody phage display library from patients with colorectal cancer

AIM: To construct the natural immune Fab antibody phage display libraries of colorectal cancer and to select antibodies related with colorectal cancer.

METHODS: Extract total RNA from tissue of local cancer metastasis lymph nodes of patients with colorectal cancer. RT-PCR was used to amplify the heavy chain Fd and light chain κ and the amplification products were inserted successively into the vector pComb3 to construct the human libraries of Fab antibodies. They were then panned by phage display technology. By means of Dot immunoblotting and ELISA, the libraries were identified and the Fab phage antibodies binding with antigens of colorectal cancer were selected.

RESULTS: The amplified fragments of Fd and κ gained by RT-PCR were about 650 bp. Fd and κ PCR products were subsequently inserted into the vector pComb3, resulting in a recombination rate of 40% and the volume of Fab phage display library reached 1.48 × 10⁶. The libraries were enriched about 120-fold by 3 cycles of adsorption-elution-multiplication (panning). Dot immunoblotting showed Fab expressions on the phage libraries and ELISA showed 5 clones of Fab phage anti bodies which had binding activities with antigens of colorectal cancer.

CONCLUSION: The natural immune Fab antibody phage display libraries of colorectal cancer were constructed. They could be used to select the relative antibodies of colorectal cancer.

Post-transcriptional stimulation of the assembly and secretion of triglyceride-rich apolipoprotein B lipoproteins in a mouse with selective deficiency of brown adipose tissue, obesity, and insulin resistance

A mouse model of insulin resistance and its associated dyslipidemia was generated by crossing mice expressing human apolipoprotein B (apoB) with mice lacking only brown adipose tissue (BATless). On a high fat diet, male apoB/BATless mice became obese, hypercholesterolemic, hypertriglyceridemic, and hyperinsulinemic compared with control apoB mice. Fast performance liquid chromatography revealed increased triglyceride concentrations in intermediate density lipoprotein/low density lipoprotein (LDL) and reduced high density lipoprotein cholesterol concentrations. Inhibition of lipolysis by the drug, tetrahydrolipostatin, demonstrated that very low density lipoprotein-sized particles were initially secreted. Metabolic studies employing Triton WR-1339 and either [(3)H]glycerol or [(3)H]palmitate showed that the hypertriglyceridemia in apoB/BATless mice was due to the increased synthesis and secretion of triglyceride. Furthermore, lipoprotein lipase and hepatic lipase activities were not defective. ApoB was also secreted at increased rates in the apoB/BATless mice. Similar levels of apoB mRNA in apoB and apoB/BATless mice indicated that apoB secretion was regulated post-transcriptionally. LDL receptor mRNA was increased in the apoB/BATless mice, indicating that the observed increase in apoB-lipoprotein secretion was not due to their decreased reuptake. Finally, mRNA levels of the large subunit of microsomal triglyceride transfer protein, a required component for very low density protein assembly, were not different between apoB and apoB/BATless mice. This rodent model should prove useful in exploring mechanisms underlying the regulation of apoB secretion in the context of insulin resistance.

[Expression of c-jun mRNA in brain stem following moderate lateral fluid percussion brain injury in rats]

AIM

To study the expression of c-jun in brain stem following moderate lateral fluid percussion brain injury in rats, and to observe the temporal patterns of its expressions following percussion.

METHODS

Male Sprague-Dawley rats were divided into normal control, sham operation control and injury groups. The rats of injury group subjected to moderate lateral fluid percussion injury (0.2MPa), and then were subdivided into 5 min, 15 min, 30 min, 1 h, 2 h, 4 h, 8 h and 12 h groups according to the time elapsed after injury. The expression of c-jun was studied by immunohistochemistry and in situ hybridization.

RESULTS

After percussion for 15 min, Jun positive neurons increased in brain stem progressively. At 5 min after percussion, the induction of c-jun mRNA was increased, remained elevated up to 2h after brain injury and then decreased gradually.

CONCLUSION

The induction and expression of the c-jun in brain stem after fluid percussion brain injury were increased rapidly and lasted for a long time.

Successful production of offspring after superovulation and in vitro culture of embryos from domestic ferrets (Mustela putorius furos)

In an effort to expand the use of ferrets as models for genetic disease, several experimental parameters that are required for successful genetic manipulation in this species were investigated. Optimum superovulation (19.3 +/- 0.6 oocytes and embryos per female) was achieved after injections of 100 iu equine chorionic gonadotrophin (eCG) and 150 iu human chorionic gonadotrophin (hCG). The ovulation rate achieved by the treatment was more than double that induced by mating. Mating with a male immediately after hCG treatment did not significantly alter the number of oocytes ovulated or the number of embryos present, indicating that mating is not required for superovulation in ferrets. Of embryos harvested at the one-cell stage, 64.5% and 47.1% developed into blastocysts when cultured in vitro in CZB or TCM-199 plus 10% fetal bovine serum (FBS) media, respectively. In contrast, only 17.1% of embryos cultured in vitro in NCSU-23 developed to the blastocyst stage. Both freshly retrieved and in vitro cultured embryos from cinnamon-coloured parents produced live young when transferred at the eight-cell stage into albino, pseudo-pregnant recipients. The percentage of kits delivered relative to embryos transferred was 61% for freshly retrieved embryos and 32% for embryos cultured in vitro. These results demonstrate successful embryo transfer in ferrets and provide a basis for further study of genetic modelling approaches in this species after embryo manipulation.

Successful production of offspring after superovulation and in vitro culture of embryos from domestic ferrets (Mustela putorius furos)

In an effort to expand the use of ferrets as models for genetic disease, several experimental parameters that are required for successful genetic manipulation in this species were investigated. Optimum superovulation (19.3 +/- 0.6 oocytes and embryos per female) was achieved after injections of 100 iu equine chorionic gonadotrophin (eCG) and 150 iu human chorionic gonadotrophin (hCG). The ovulation rate achieved by the treatment was more than double that induced by mating. Mating with a male immediately after hCG treatment did not significantly alter the number of oocytes ovulated or the number of embryos present, indicating that mating is not required for superovulation in ferrets. Of embryos harvested at the one-cell stage, 64.5% and 47.1% developed into blastocysts when cultured in vitro in CZB or TCM-199 plus 10% fetal bovine serum (FBS) media, respectively. In contrast, only 17.1% of embryos cultured in vitro in NCSU-23 developed to the blastocyst stage. Both freshly retrieved and in vitro cultured embryos from cinnamon-coloured parents produced live young when transferred at the eight-cell stage into albino, pseudo-pregnant recipients. The percentage of kits delivered relative to embryos transferred was 61% for freshly retrieved embryos and 32% for embryos cultured in vitro. These results demonstrate successful embryo transfer in ferrets and provide a basis for further study of genetic modelling approaches in this species after embryo manipulation.

Primate epididymis-specific proteins: characterization of ESC42, a novel protein containing a trefoil-like motif in monkey and human

Epididymal secreted proteins promote sperm maturation and fertilizing capacity by interacting with sperm during passage through the epididymis. Here we investigate the molecular basis of sperm maturation by isolating cDNA clones for novel epididymis-specific expressed sequences. Thirty-six novel cDNAs were isolated and sequenced from a subtracted Macaca mulatta epididymis library. The clones encode proteins with a range of motifs characteristic of protein-modifying enzymes, protease inhibitors, hydrophobic ligand-binding and transport proteins, extracellular matrix-interacting proteins, and transcription regulatory factors. The full length coding sequences were obtained for 11 clones representing a range of abundance levels. Expression of each is regionally localized and androgen regulated. The most abundant, ESC42, contains a cysteine-rich region similar to the signature binding domain of the trefoil family of motogenic wound repair proteins. The monkey and human proteins are nearly 90% identical. Immunohistochemical staining revealed that the protein is most abundant in the epithelium of the caput and is also present in the lumen and bound to sperm. The ESC42 gene, located on chromosome 20q11, contains two exons encoding two nearly identical predicted signal peptides and a third exon encoding the rest of the protein.

Detection of amp C in Enterobacter cloacae in China

PCR amplification of 55 strains of Enterobacter cloacae indicated 51 of them had amp C structural gene verified by DNA sequence and Southern blotting. All PCR products were cleaved into 666- and 328-bp fragments by Kpn1 restriction enzyme. Imipenem was the most potent inducer for mRNA expression of amp C gene and beta-lactamase activity. The beta-Lactamase inhibitor R0481220 strongly inhibited Amp C beta-lactamases; 96.4% (53/55) of Enterobacter cloacae producing Amp C enzyme were susceptible to cefepime.

Effects of melittin on isolated papillary muscles of guinea pig

AIM

To investigate the effect of melittin (Mel) on papillary muscles of guinea pigs.

METHODS

Contraction of papillary muscles were examined by conventional method and action potentials (AP) were recorded by standard glass microelectrode technique.

RESULTS

Mel (0.5, 3 micromol/L) significantly increased the contractility of guinea pig papillary muscles while 5 micromol/L exerted dual action with a transient decrease followed by an increase of the contractility. Mel shortened the functional refractory period (FRP) at concentrations of 0.5, 3, and 5 micromol/L and increased the automaticity induced by adrenaline (Adr) at 3 and 5 micromol/L. Mel shifted the duration-intensity curve upward at 3 micromol/L. It shortened the action potential duration (APD) of fast action potential (FAP), decreased the action potential amplitude (APA) and resting potential (RP) at 0.5 and 3 micromol/L. As to slow action potential (SAP), Mel 0.8 micromol/L shortened APD20 and APD50, and decreased APA and RP.

CONCLUSION

Mel increased the contractility and automaticity of papillary muscles, shortened the FRP, decreased the excitability, shortened the APD, and decreased APA and RP of AP.

Differential expression of CCAAT/enhancer-binding protein-delta (c/EBPdelta) in rat androgen-dependent tissues and human prostate cancer

CCAAT/enhancer-binding protein delta (C/EBPdelta) is a nuclear transcription factor that regulates cellular growth and differentiation. In this study we demonstrate that C/EBPdelta gene expression is differentially regulated in rat androgen-dependent tissues and human prostate cancer. C/EBPdelta messenger RNA (mRNA) levels were very low in adult rat ventral prostate, epididymis, and testis. In ventral prostate and epididymis, expression of C/EBPdelta mRNA increased more than sixfold when testicular testosterone was eliminated by surgical castration or treatment with ethane-1,2-dimethanesulfonate (EDS). Testosterone replacement reduced C/EBPdelta mRNA levels to near control values in both tissues. CWR22 is a human prostate cancer xenograft that mimics biological characteristics of androgen-dependent and androgen-independent human prostate cancer. In androgen-dependent CWR22 tumors, expression of C/EBPdelta mRNA declined in response to castration. Both C/EBPdelta mRNA and protein levels increased following testosterone administration. However, C/EBPdelta mRNA and protein levels were variable in recurrent CWR22 tumors growing in the absence of testicular androgen for approximately 5 months. C/EBPdelta expression was also variable in androgen-independent human prostate carcinomas (n = 3), although mRNA levels were substantially lower than those in androgen-dependent tumors (n = 3). These studies demonstrate that androgen down-regulates C/EBPdelta levels in androgen-dependent rat tissues, but induces C/EBPdelta expression in androgen-dependent human prostate cancer. Deregulation of C/EBPdelta occurs when prostate cancer progresses to the androgen-independent state.

An antimicrobial peptide gene found in the male reproductive system of rats

Little is known about the innate defense mechanisms of the male reproductive tract. We cloned a 385-base pair complementary DNA and its genomic DNA named Bin1b that is exclusively expressed in the caput region of the rat epididymis and that is responsible for sperm maturation, storage, and protection. Bin1b exhibits structural characteristics and antimicrobial activity similar to that of cationic antimicrobial peptides, beta-defensins. Bin1b is maximally expressed when the rats are sexually mature and can be up-regulated by inflammation. Bin1b appears to be a natural epididymis-specific antimicrobial peptide that plays a role in reproductive tract host defense and male fertility.

[Experimental study of allogenic tendon with sheath grafting in chicken]

OBJECTIVE

To investigate availability of deep freeze stored allogenic tendon with sheath grafting in repairing the tendon and sheath defect in the II area of flexor digitorum tendon.

METHODS

Sixty chickens with tendon and sheath defect were divided into 2 groups randomly, group A was treated with allogenic grafting and group B was treated with autogenic grafting, these two groups were divided into two subgroups respectively, they were, group A1 allogenic tendon with whole sheath grafting, group A2 allogenic tendon with partial sheath grafting, group B1 autogenic tendon with whole sheath grafting and group B2 autogenic tendon with whole sheath grafting. All the allogenic grafts were treated by deep freeze. Histomorphological study, histoimmunological study and slipping function of the grafts were measured after operation.

RESULTS

In group A1 and B1, the local reaction was sever, the nutrition of tendon graft was barricaded by the whole sheath resulting in adhesion, degeneration and necrosis. In group A2 and B2, the tendon graft healed well and little adhesion existed between tendon and sheath. The results showed that there were significant differences between tendon grafting with whole sheath and tendon grafting with partial sheath.

CONCLUSION

Deep freeze store can reduce the immunogenicity of allogenic tendon with sheath. Allogenic tendon with partial sheath grafting can be used as a new biological material for repairing the tendon and sheath defect.

[Genetic transformation of hairy roots in Trichosanthes kirilowii Maxim. by Ti and Ri plasmids]

OBJECTIVE

To establish a hairy root culture system by double transformation for Trichosanthes kirilowii.

METHOD

1. Crown galls were induced by direct infection of sterile seedlings of T. kirilonii with Agrobacterium tumefaciens C58, and then the hairy roots were obtained from the regenerated plants by infection with A. rhzogenes 15834; 2. Transformation of Ti and Ri plasmids was inspected by high-pressure-paper electrophoresis; 3. The protein contents in the tissues of T. kirilowii were inspected by spectrophotometer and SDS-PAGE.

RESULT

A hairy root culture system has been established successfully by double transformation with Ti and Ri plasmids in T. kirilowii.

CONCLUSION

Compared with the ordinary hairy roots, the double transformed hairy roots grow faster but retain similar protein contents.

Laser confocal microscopic study of pH profiles of synthetic absorbable fibers upon in vitro hydrolytic degradation

The objective of this study was to develop a new and non-destructive technique to measure the interior pH of synthetic absorbable biomaterials. Such a measurement would provide the required experimental evidence for validating the postulated theory that the accumulation of acidic hydrolytic degradation products within the interior of aliphatic polyesters is responsible for the observed accelerated degradation of this class of absorbable biomaterials. This new technique used a laser scanning confocal microscope coupled with pH sensitive fluorescent dyes like Texas Red sulfonyl chloride. The capability of optical thin sectioning of a laser confocal microscope would permit a non-destructive examination of the interior of biomaterials. Poly-p-dioxanone suture fibers (PDSII) of size 2/0 were used as the model compound for this new technique. The pH values of the unhydrolyzed and partially hydrolyzed PDSII fibers were found to decrease with increasing depth from the fiber surface and reached as low as about 3.5 at 70 microm depth. The largest depth that an interior pH could be measured within absorbable biomaterials was determined by the opacity of the biomaterials, i.e. a higher depth for a less opaque material. The observed interior pH profiles were correlated to the unique morphologic structure of PDSII fibers.

The in vitro activity of sulbactam combined with third generation cephalosporins against third generation cephalosporin-resistant bacteria

The in vitro activity of the beta-lactamase inhibitor sulbactam combined with cefuroxime, cefotaxime or ceftazidime in the ratio of 1:1 was studied against ceftazidime- or cefuroxime-resistant Gram-negative rods and Staphylococcus aureus. Sulbactam enhanced the antibacterial activities of cefuroxime, cefotaxime and ceftazidime against Gram-negative rods. The MIC(90) of ceftazidime against Escherichia coli, Enterobacter cloacae, Citrobacter freundii, Acinetobacter spp. and Pseudomonas aeruginosa was reduced 4-fold and that of cefotaxime against E. coli, E. cloacae, C. freundii and Acinetobacter spp. reduced by 2-4-fold. However, sulbactam did not enhance the activities of cefuroxime, cefotaxime or ceftazidime against S. aureus, enterococci and Stenotrophomonas maltophilia. With the combination of sulbactam and ceftazidime at the ratio of 1:1, 38.4% of E. coli, 45.3% of E. cloacae, 66.6% of C. freundii and 60% of Acinetobacter spp. initially resistant to ceftazidime became susceptible.

[A survey of the changes of serum inorganic salts and alkaline phosphatase after jaw fractures]

OBJECTIVE

To study the changes of serum salts and alkaline phosphatase in patients with jaw fractures and its roles.

METHODS

The serum salts and alkaline phosphatase were determined in 40 cases of jaw fracture and 14 health persons.

RESULTS

The results showed that there was no significant difference in Na(+), K(+), Cl(-), Ca(2+) contents between jaw fracture group and normal group (P>0.05), but P(3-) Mg(2+), ALP levels were higher in jaw fracture group than that in normal group (P<0.05). Furthermore the Ca(2+), P(3-), Mg(2+), ALP were higher in multiple or communition fracture of jaw than in single or double line fracture (P<0.05) except Ca content. The level of Ca(2+) was higher in single jaw fracture than in jaw damage with whole body injury (P>0.05) but the levels of P(3-),Mg(2+), ALP were no difference (P>0.05). As the same all the Ca(2+), P(3-), Mg(2+), ALP levels were higher in early stage of fracture than in 4 weeks after fracture (P<0.05).

CONCLUSION

The contents of Ca(2+) P(3-), Mg(2+) ALP were increased after the axilla mandible were fractured and it has an important regulation role in the activity of osteoblast and osteoclast in healing of fractured jaw.