Air Ring Effect on Blown Film Dynamics

The air ring has an effect on blown film dynamics. By using a momentum macrobalance, an analytical solution for the pressure on the outer surface of the bubble is obtained which is in fairly good agreement with our aerodynamic experimental data. Since the pressure is related to the hoop stress, a more complete prediction of the bubble shape is attained by taking the air ring effect into account.

Downregulation of Mcl-1 through inhibition of translation contributes to benzyl isothiocyanate-induced cell cycle arrest and apoptosis in human leukemia cells

Benzyl isothiocyanate (BITC) is one of the compounds of ITCs' family that has attracted a great deal of interest because of its ability to exhibit anticancer activity. In this study, we investigated the effects of BITC on cell cycle arrest and apoptosis in human leukemia cell lines, primary leukemia cells, and nude mice Jurkat xenograft. Exposure of Jurkat cells to BITC resulted in dose- and time-dependent increase in apoptosis, caspase activation, cytochrome c release, nuclear apoptosis-inducing factor (AIF) accumulation, Bcl2-associated X protein (Bax) translocation, and myeloid cell leukemia-1 (Mcl-1) downregulation. Treatment with these cells also resulted in cell cycle arrest at the G2/M phase. The G2/M-arrested cells are more sensitive to undergoing Mcl-1 downregulation and apoptosis mediated by BITC. BITC downregulates Mcl-1 expression through inhibition of translation, rather than through a transcriptional, post-translational, or caspase-dependent mechanism. Dephosphorylation of eukaryotic initiation factor 4G could contribute to the inhibition of Mcl-1 translation mediated by BITC. Furthermore, ectopic expression of Mcl-1 substantially attenuates BITC-mediated lethality in these cells, whereas knockdown of Mcl-1 through small interfering RNA significantly enhances BITC-mediated lethality. Finally, administration of BITC markedly inhibited tumor growth and induced apoptosis in Jurkat xenograft model in association with the downregulation of Mcl-1. Taken together, these findings represent a novel mechanism by which agents targeting Mcl-1 potentiate BITC lethality in transformed and primary human leukemia cells and inhibitory activity of tumor growth of Jurkat xenograft model.

New dual gas puff imaging system with up-down symmetry on experimental advanced superconducting tokamak

Gas puff imaging (GPI) offers a direct and effective diagnostic to measure the edge turbulence structure and velocity in the edge plasma, which closely relates to edge transport and instability in tokamaks. A dual GPI diagnostic system has been installed on the low field side on experimental advanced superconducting tokamak (EAST). The two views are up-down symmetric about the midplane and separated by a toroidal angle of 66.6°. A linear manifold with 16 holes apart by 10 mm is used to form helium gas cloud at the 130×130 mm (radial versus poloidal) objective plane. A fast camera is used to capture the light emission from the image plane with a speed up to 390,804 frames/s with 64×64 pixels and an exposure time of 2.156 μs. The spatial resolution of the system is 2 mm at the objective plane. A total amount of 200 Pa.L helium gas is puffed into the plasma edge for each GPI viewing region for about 250 ms. The new GPI diagnostic has been applied on EAST for the first time during the recent experimental campaign under various plasma conditions, including ohmic, L-mode, and type-I, and type-III ELMy H-modes. Some of these initial experimental results are also presented.

Polymorphism identification in the goat <i>THRSP</i> gene and association analysis with growth traits

Abstract. cIn this study, we reported the analysis of THRSP gene polymorphisms in 610 goats of three breeds: Xinong Saanen (SN), Guanzhong (GZ) and Boer (BG). We identified new allelic variant: P2-G39294A (GenBank acc. no. JN618075) in the three goat breeds. At P2 locus, GG, GA and AA genotypes were found in the three goat breeds. The frequencies of G allele were 0.54–0.55 and frequencies of A allele were 0.46–0.45, and the PIC was 0.37. The SNP locus was in Hardy-Weinberg disequilibrium in Boer goat breed (P<0.05). Association of polymorphisms with growth traits was done at P2 locus in Boer goat breed. The result showed that AA genotype had remarkable growth traits at P2 locus (P<0.05). Therefore, these results suggest that THRSP gene is a strong candidate gene that affects growth traits in goat.

Viral and Mycoplasma pneumoniae community-acquired pneumonia and novel clinical outcome evaluation in ambulatory adult patients in China

Few studies have addressed the etiology and clinical outcomes of community-acquired pneumonia (CAP) treated in an ambulatory setting. We investigated the etiology by the culture of Mycoplasma pneumoniae, urine antigen testing of Streptococcus pneumoniae and Legionella pneumoniae, and DNA or RNA determination of eight kinds of respiratory virus DNA or RNA. An etiological diagnosis was made in 51.8% of 197 patients. The most common pathogens were M. pneumoniae (29.4%) followed by influenza virus A, parainfluenza virus, adenovirus, human metapneumovirus (9.6%), and S. pneumoniae (4.1%). Patients with mycoplasma infections were younger, less likely to have comorbidities, and less likely to have adequate sputum for gram stain and culture. Patients with viral infections were older and more likely to have poorly defined nodules on chest X-ray (CXR) or computed tomography (CT) scan. Among patients infected with M. pneumoniae, those with quinolones as initial prescriptions had shorter duration of fever after the initiation of antibiotics than patients with β-lactams, macrolides, or β-lactams + macrolides (p < 0.05). This study suggests that M. pneumoniae and respiratory viruses were the most frequent pathogens found in ambulatory adult CAP patients and quinolones were better than β-lactams, macrolides, or β-lactams + macrolides in the resolution of fever of M. pneumoniae pneumonia.

Application of life cycle assessment for an evaluation of wastewater treatment and reuse project--case study of Xi'an, China

In order to illuminate the benefit of a wastewater treatment and reuse project, a life cycle assessment (LCA) model was proposed by combining the process-based LCA and the input-output based LCA in one framework and using energy consumption as the sole parameter for quantitative evaluation of the project. The life cycle consumption was evaluated mainly by life cycle inventory (LCI) analysis taking into account the construction phase, operation phase and demolishment phase of the project. For evaluating the life cycle benefit of treated water reuse, attention was paid to the decrease of secondary effluent discharge and water saving. As a result of comprehensive LCA analysis of a case project in Xi'an, China, it was understood that the life cycle benefit gained from treated wastewater reuse much surpassed the life cycle energy consumption. The advantage of wastewater treatment and reuse was well shown by LCA analysis using the proposed model.

Meat quality parameters of descendants by grading hybridization of Boer goat and Guanzhong Dairy goat

Chemical composition, cholesterol levels, fatty acid profile, meat taste, and quality parameters were evaluated in 48 buck kids from goats of the Guanzhong Dairy breed (Group G) and their crosses (Group F1: 1/2 Boermale symbolx1/2 Guanzhong Dairyfemale symbol; Group F2: 3/4 Boermale symbolx1/4 Guanzhong Dairyfemale symbol; Group F3: 7/8 Boermale symbolx1/8 Guanzhong Dairyfemale symbol) at different ages of slaughter (6, 8 and 10 months). Results indicated that grading hybridization (P<0.05) affected meat nutritive value. The muscle of hybrid goats had lower crude fat and cholesterol, higher crude protein, and greater proportion of C18:2 and C18:3 than that of Group G at each age. Group F1 goats had better (P<0.05) desirable fatty acid (DFA) and polyunsaturated fatty acid (PUFA) to saturated fatty acid (SFA) ratios and greater (C18:0+C18:1/C16:0) ratios (P<0.01) than those of the other genotypes. Furthermore, the muscles of hybrid goats were tenderer and juicier compared to Group G. In all four groups, cholesterol levels increased (P<0.01), muscle color became redder (P<0.05) and tenderness decreased (P<0.05) with increasing age. The low level of lipids and cholesterol, good meat quality, and the higher ratio of unsaturated to SFA in Group F1 indicate better quality for human consumption.

Laser-based diagnostics applied to the study of BN nanotubes synthesis

The boron nitride nanotubes (BNNTs) synthesis, using CO2-laser vaporization of a BN target under nitrogen gas, is investigated by UV-laser induced fluorescence (LIF) of the vapor phase and UV-Rayleigh scattering (RS) of the gas-suspended nanoparticles. The LIF signal from B atoms is mainly detected in the 1.5 mm-thick region above the BN target. It originates from a boron-rich vapor region confined near the hot boron droplet formed at the target surface. Then, recombination between hot boron and N2 gas occurs through a fast condensation process as revealed by both the depletion of B atoms from the vapor phase and the RS signal arising from the grown BN nanoparticles. Fluorescence spectra exhibit a strong peak at 250 nm due to boron fluorescence and mainly to nanoparticles Rayleigh scattering. A narrow peak is observed at 210 nm and a broader peak at 189 nm. These bands are tentatively assigned to fluorescence or photoluminescence (PL) from gaseous or solid BN species respectively since both gas and solid phases coexist in the plume due to the rapid cooling process. Two very weak bands occur at 308 nm and 350 nm. They are related to PL of defects bands from BN nanostructures on the basis of ex situ PL spectra of h-BN crystallites and multi-wall BNNTs. Detection of oxygen impurities is shown feasible through LIF from BO radical which is detected just above the BN target evaporated under vacuum pressure (approximately 1 mbar). An optical diagnostic strategy is demonstrated from these first in situ observations during BNNTs synthesis.

Investigation of rice transgene flow in compass sectors by using male sterile line as a pollen detector

Rice is the most important staple food in the world. The rapid development of transgenic rice and its future commercialization have raised concerns regarding transgene flow and its potential environmental risk. It is known that rice is a self-pollinated crop; the outcrossing rate between common cultivars is generally less than 1%. In order to improve the detection sensitivity of rice transgene flow, a male sterile (ms) line BoA with a high outcrossing rate was used as a pollen detector in this study. A concentric circle design was adopted, in which the transgenic rice B2 containing bar gene as a pollen donor was planted in the center circle and the recipient BoA was planted in eight compass sectors. The frequency of transgene flow in compass sectors was analyzed by continuous sampling to generate cumulative data. The results of two years with sound reproducibility demonstrated that the rice gene flow was closely associated with the wind direction. According to the mean frequency of transgene flow, the eight sectors can be divided into two groups: a higher frequency group downstream of the prevailing wind (DPW) with a mean frequency ranging from 6.47 to 26.24%, and a lower frequency group lateral to or upstream of the prevailing wind (UPW) with a mean frequency of 0.39 to 3.03%. On the basis of the cumulative data, 90-96% of the cumulative gene flow events occurred in the four DPW sectors, while it was 4-10% in the four UPW sectors. By using these systematic data, simulation models and isograms of transgene flow in the eight compass sectors were calculated and drawn, respectively.

Evidence that MIG-6 is a tumor-suppressor gene

Mitogen-inducible gene 6 (MIG-6) is located in human chromosome 1p36, a locus frequently associated with human lung cancer. MIG-6 is a negative regulator of epidermal growth factor (EGF) signaling, and we show that Mig-6 - like EGF - is induced by hepatocyte growth factor/scatter factor (HGF/SF) in human lung cancer cell lines. Frequently, the receptors for both factors, EGFR and Met, are expressed in same lung cancer cell line, and MIG-6 is induced by both factors in a mitogen-activated protein kinase-dependent fashion. However, not all tumor lines express MIG-6 in response to either EGF or HGF/SF. In these cases, we find missense and nonsense mutations in the MIG-6 coding region, as well as evidence for MIG-6 transcriptional silencing. Moreover, germline disruption of Mig-6 in mice leads to the development of animals with epithelial hyperplasia, adenoma, and adenocarcinoma in organs like the lung, gallbladder, and bile duct. These data suggests that MIG-6 is a tumor-suppressor gene and is therefore a candidate gene for the frequent 1p36 genetic alterations found in lung cancer.

Management of abnormal uterine hemorrhage with atypical endometrial hyperplasia by transcervical resection of endometrium

The aim of the study was to assess the feasibility and effect of treating atypical endometrial hyperplasia (AEH) with transcervical resection of endometrium (TCRE). Five cases of AEH incapable of hysterectomy for various reasons were treated with TCRE. All patients were followed up for 3-4 years postoperation to evaluate the thickness of endometrium, uterine cavity, and prognosis of the disease. All the patients provided informed consent for TCRE. In all five cases treated with TCRE, case 1 was for senility, hypertension, diabetes mellitus, and obesity; case 4 for senility, obsolete cerebral infarction, and hemiplegia; case 5 for uremia and chronic dysfunction of coagulation after renal transplantation; cases 2 and 3 for rejection of hysterectomy. All cases were followed up for more than 3 years after operation. Four had amenorrhea and one had dropping menses. The thickness of endometrium was no more than 5 mm in all the cases. TCRE is one available microinvasive surgery alternative to hysterectomy for AEH patients contraindicated to hysterectomy.

Spatial evolutions of Co and Ni atoms during single-walled carbon nanotubes formation: measurements and modeling

Spatial investigations of nickel and cobalt atoms and of C2 and C3 radicals are performed by laser induced fluorescence (LIF) in a continuous CO2 laser-vaporization reactor during the synthesis of single-walled carbon nanotubes. The chemical composition of the gas vaporized from bimetallic Ni/Co catalysts-carbon targets is determined using a chemical kinetic model. In this model, the evolution of Ni and Co atoms is driven by kinetics of condensation/evaporation process of pure metal clusters. Metal-carbon clusters are assumed to form from soot particles (C80) and 128-atom metal clusters. Spatial profiles of Ni and Co atoms obtained by LIF are compared with the calculations to validate the modeling and to adjust the input data. The value of the initial molar fraction of carbon-metal mixture diluted in helium is determined through a parametric study. Good agreement is found between the measured and the calculated evolution of Ni for a molar fraction of the helium diluent ranging from 10 to 15%. To fit the spatial profile of Co, the activation energy is adjusted in the evaporation rate, changing the cobalt dimer bond energy. The latter is found to be largely uncertain; and three values are tested: 167, 208, and 230 kJ x mol(-1). From comparison, the activation energy is found to be 208 kJ x mol(-1). However, the C2 LIF profiles show that the depletion of C2 is accelerated when cobalt is present. The observed Co evolutions suggest that small Co-C clusters are easier and/or faster to form compared to Ni-C clusters.

Management of abnormal uterine hemorrhage with atypical endometrial hyperplasia by transcervical resection of endometrium

The aim of the study was to assess the feasibility and effect of treating atypical endometrial hyperplasia (AEH) with transcervical resection of endometrium (TCRE). Five cases of AEH incapable of hysterectomy for various reasons were treated with TCRE. All patients were followed up for 3–4 years postoperation to evaluate the thickness of endometrium, uterine cavity, and prognosis of the disease. All the patients provided informed consent for TCRE. In all five cases treated with TCRE, case 1 was for senility, hypertension, diabetes mellitus, and obesity; case 4 for senility, obsolete cerebral infarction, and hemiplegia; case 5 for uremia and chronic dysfunction of coagulation after renal transplantation; cases 2 and 3 for rejection of hysterectomy. All cases were followed up for more than 3 years after operation. Four had amenorrhea and one had dropping menses. The thickness of endometrium was no more than 5 mm in all the cases. TCRE is one available microinvasive surgery alternative to hysterectomy for AEH patients contraindicated to hysterectomy.

Muscle stem cells can act as antigen-presenting cells: implication for gene therapy

Research has shown that the use of a muscle-specific promoter can reduce immune response and improve gene transfer to muscle fibers. We investigated the efficiency of direct and ex vivo gene transfer to the skeletal muscles of 6- to 8-week-old mdx mice by using two adenoviral vectors: adenovirus (AD) encoding the luciferase gene under the cytomegalovirus (CMV) promoter (ADCMV) and AD encoding the same gene under the muscle creatine kinase (MCK) promoter (ADMCK). Direct intramuscular injection of ADMCK triggered a lower immune response that enabled more efficient delivery and more persistent expression of the transgene than did ADCMV injection. Similarly, ex vivo gene transfer using ADCMV-transduced muscle-derived stem cells (MDSCs) induced a stronger immune response and led to shorter transgene expression than did ex vivo gene transfer using ADMCK-transduced MDSCs. This immune response was due to the release of the antigen after MDSC death or to the ADCMV-transduced MDSCs acting as antigen-presenting cells (APCs) by expressing the transgene and rapidly initiating an immune response against subsequent viral inoculation. The use of a muscle-specific promoter that restricts transgene expression to differentiated muscle cells could prevent MDSCs from becoming APCs, and thereby could improve the efficiency of ex vivo gene transfer to skeletal muscle.

Risk factors and clinical outcomes of nosocomial multi-drug resistant Pseudomonas aeruginosa infections

Risk factors for multi-drug resistant Pseudomonas aeruginosa (MDRP) infections were investigated using a case-control study design involving MDRP patients (N = 44) and controls (N = 68). A retrospective cohort study was performed to study the predictive factors of clinical outcome in MDRP patients. Multivariate analysis demonstrated that previous exposure to imipenem/meropenem [odds ratio (OR), 44.8] and mechanical ventilation (OR 8.2) were risk factors for nosocomial infections of MDRP. Of 44 cases of MDRP infections, 20 patients died directly from P. aeruginosa infections. Pulsed-field gel electrophoresis (PFGE) analysis on serial isolates from three patients showed that profiles of isolates from the same patient were closely related or indistinguishable. Multivariate analysis demonstrated that patients with adverse clinical outcomes were more likely to have been treated with mechanical ventilation (OR 12.8), and more likely to have MDRP resistance patterns that did not change during treatments (OR 26.5). We concluded that mechanical ventilation and previous exposure to imipenem/meropenem were independent risk factors for MDRP infections, while mechanical ventilation and antibiotic resistance switch were predictive factors of outcomes of MDRP infections.

Modeling stem cell population growth: incorporating terms for proliferative heterogeneity

Expansion of the undifferentiated stem cell phenotype is one of the most challenging aspects in stem cell research. Clinical protocols for stem cell therapeutics will require standardization of defined culture conditions. A first step in the development of predictable and reproducible, scalable bioreactor processes is the development of mathematical growth models. This paper provides practical models for describing cell growth in general, which are particularly well suited for examining stem cell populations. The nonexponential kinetics of stem cells derive from proliferative heterogeneity, which is biologically recognized as mitosis, quiescence, senescence, differentiation, or death. Here, we examined the assumptions of the Sherley model, which describes heterogeneous expansion in the absence of cell loss. We next incorporated terms into the model to account for A) cell loss or apoptosis and B) cell differentiation. We conclude that the basic assumptions of the model are valid and a high correlation between the modified equations and experimental data obtained using muscle-derived stem cells was observed. Finally, we demonstrate an improved estimation of the kinetic parameters. This study contributes to both the biological and mathematical understanding of stem cell dynamics. Further, it is expected that the models will prove useful in establishing standardization of cell culture conditions and scalable systems and will be required to develop clinical protocols for stem cell therapeutics.

D-lactic acidosis secondary to short bowel syndrome

A 12 year old boy presented with 11 episodes of weakness, ataxia, nausea, slurred speech, dehydration, and sometimes severe lethargy bordering on coma. A year previously the boy had small intestinal resections leaving 20 cm of small bowel remaining. D-lactic acidosis was diagnosed on the basis of a D-lactate level of 5.23 mmol/l. The clinical presentation of the disease is recurrent episodes of unusual neurological manifestations and severe metabolic acidosis. The diagnosis is dependent on the presentations and the plasma D-lactate level. Development of the syndrome seems to be the effect of the accumulation of D-lactic acid.

Effect of oxidation of low-density lipoprotein on drug binding affinity studied by high performance frontal analysis-capillary electrophoresis

The effect of oxidation of low-density lipoprotein (LDL) on the enantioselective drug binding affinity was investigated using high performance frontal analysis--capillary electrophoresis (HPFA-CE). Verapamil and nilvadipine enantiomers were used as the chiral model drugs. LDL was oxidized with copper sulfate for 0, 0.5, 1, 2, and 12 h at 37 degrees C. The HPFA-CE method enabled microdetermination of unbound drug concentrations in native and oxidized LDL solutions. It was found that the bindings between LDL and the model drugs were not enantioselective at any oxidation stage. The total binding affinity (nK) between LDL and verapamil enantiomers was increased by 3.3-, 4.6-, 7.0-, and 19-fold after 0.5, 1, 2, and 12 h oxidation, respectively, whereas the nK value between nilvadipine and LDLwas increased by 1.3-, 1.4-, 1.4-, and 1.7-fold in the same reaction times, respectively. These results indicate that the LDL oxidation enhances the drug binding affinity, and the affinity of verapamil is increased more sensitively than that of nilvadipine. The nK value of each model drug increased steeply after the first 2 h oxidation, followed by the gradual increase after the next 10 h oxidation. It is considered that the net increase in the negative charges and/or the formation of hydroperoxides in the first 2 h oxidation enhances the drug-LDL binding more significantly than the formation of aldehydes or Schiff bases in the following 10 h oxidation.

[Clinical analysis of nosocomial infection of extended spectrum beta-lactamase-producing bacteria]

OBJECTIVE

To investigate the clinical characteristics of nosocomial infection of extended spectrum beta-lactamase(ESBL)- producing bacteria.

METHODS

The data of 50 cases of ESBL(+) E. coli and K. pneumonia from January to November 1999 in Peking Union Medical Hospital were analysed; 45 cases of ESBL (-) infection were randomly selected as controls. t-test and chi-square tests were used for statistical analysis.

RESULTS

Long time hospitalization and use of the third generation cephalosporins were risk factors for ESBL(+) pathogen infection(P < 0.02); the prevalence of ESBL(+) bacteria infection in abdominal and pelvic cavity was higher than that of ESBL(-) bacteria(P < 0.02); the outcome of properly treated group(sensitive antibiotics were used within 72 hours) was much better than improperly treated group. All ESBL(+) bacteria were sensitive to imipenam, the resistance rate of ESBL(+) bacteria to cefmetazole, amikacin and piperacillin/tazobactam was low; the in vitro activity of ceftazidim to ESBL(+) bacteria was high but the in vivo activity is still under study.

CONCLUSION

The mortality of ESBL(+) bacteria infection was high; the outcome would be improved if sensitive antibiotics were chosen as soon as the diagnosis was made.

Neutralizing monoclonal antibodies to hepatocyte growth factor/scatter factor (HGF/SF) display antitumor activity in animal models

The hepatocyte growth factor (HGF/SF) receptor, Met, regulates mitogenesis, motility, and morphogenesis in a cell type-dependent fashion. Activation of Met via autocrine, paracrine, or mutational mechanisms can lead to tumorigenesis and metastasis and numerous studies have linked inappropriate expression of this ligand-receptor pair to most types of human solid tumors. To prepare mAbs to human HGF/SF, mice were immunized with native and denatured preparations of the ligand. Recloned mAbs were tested in vitro for blocking activity against scattering and branching morphogenesis. Our results show that no single mAb was capable of neutralizing the in vitro activity of HGF/SF, and that the ligand possesses a minimum of three epitopes that must be blocked to prevent Met tyrosine kinase activation. In vivo, the neutralizing mAb combination inhibited s.c. growth in athymic nu/nu mice of tumors dependent on an autocrine Met-HGF/SF loop. Importantly, growth of human glioblastoma multiforme xenografts expressing Met and HGF/SF were markedly reduced in the presence of HGF/SF-neutralizing mAbs. These results suggest interrupting autocrine and/or paracrine Met-HGF/SF signaling in tumors dependent on this pathway is a possible intervention strategy.

Muscle-derived cell transplantation and differentiation into lower urinary tract smooth muscle

OBJECTIVES

To explore the feasibility of primary skeletal muscle-derived cell (MDC)-based tissue engineering and gene transfer into the lower urinary tract and to explore whether the injected primary skeletal MDCs can persist and differentiate into myotubes and myofibers in the bladder wall.

METHODS

Primary MDCs isolated from normal mice were first transduced with adenovirus encoding the expression of the beta-galactosidase reporter gene. Adult severe combined immunodeficiency mice (n = 12) were used in this study. The MDCs were injected into the right and left lateral bladder walls with a 10-microL Hamilton microsyringe. The amount of injected MDCs ranged from 1 to 1.5 x 10(6) cells. The tissue was harvested after 5, 35, and 70 days, sectioned, stained for fast myosin heavy chain, and assayed for beta-galactosidase expression.

RESULTS

We observed a large number of cells expressing beta-galactosidase in the bladder wall at each time point. Many myotubes and myofibers expressing beta-galactosidase and positively stained for fast myosin heavy chain were also seen in the bladder wall at 35 and 70 days after injection. Additionally, the size of the injected MDCs significantly increased during the course of the study (P <0.05).

CONCLUSIONS

We have demonstrated the long-term survival and beta-galactosidase expression of MDCs injected into the bladder wall. Moreover, our results suggest that some injected MDCs can differentiate into myofibers. These results suggest that MDCs can be a desirable substance for tissue engineering and an ex vivo method for gene transfer into the lower urinary tract.

The role of receptors in the maturation-dependent adenoviral transduction of myofibers

One of the major hurdles facing the application of adenoviral gene transfer to skeletal muscle is the maturation-dependent transduction of muscle myofibers. It was recently proposed that the viral receptors (Coxsackie and adenovirus receptor (CAR) and the integrins alphavbeta3/beta5) play a major role in the poor adenoviral transduction of mature myofibers. Here we report the findings of morphological studies designed to determine experimentally the role of receptors in the adenoviral transduction of mature myofibers. First, we observed that the expression of both attachment and internalization receptors did not change significantly during muscle development. Second, when an extended tropism adenoviral vector (AdPK) that attaches to heparan sulfate proteoglycan (HSP) is used, a significant reduction of adenoviral transduction still occurs in mature myofibers despite HSP's high expression in mature skeletal muscle fibers. Third, when the adeno-associated virus (AAV) is used, which also utilizes HSP as a viral receptor, muscle fibers at different maturities can be highly transduced. Fourth, the pre-irradiation of the skeletal muscle of newborn mice to inactivate myoblasts dramatically decreased the transduction level of Ad and AdPK, but had no effect on AAV-mediated viral transduction of immature myofibers. These results taken together suggest that the viral receptor(s) is not a major determinant in maturation-dependent adenoviral transduction of myofibers.

Clonal isolation of muscle-derived cells capable of enhancing muscle regeneration and bone healing

Several recent studies suggest the isolation of stem cells in skeletal muscle, but the functional properties of these muscle-derived stem cells is still unclear. In the present study, we report the purification of muscle-derived stem cells from the mdx mouse, an animal model for Duchenne muscular dystrophy. We show that enrichment of desmin(+) cells using the preplate technique from mouse primary muscle cell culture also enriches a cell population expressing CD34 and Bcl-2. The CD34(+) cells and Bcl-2(+) cells were found to reside within the basal lamina, where satellite cells are normally found. Clonal isolation and characterization from this CD34(+)Bcl-2(+) enriched population yielded a putative muscle-derived stem cell, mc13, that is capable of differentiating into both myogenic and osteogenic lineage in vitro and in vivo. The mc13 cells are c-kit and CD45 negative and express: desmin, c-met and MNF, three markers expressed in early myogenic progenitors; Flk-1, a mouse homologue of KDR recently identified in humans as a key marker in hematopoietic cells with stem cell-like characteristics; and Sca-1, a marker for both skeletal muscle and hematopoietic stem cells. Intramuscular, and more importantly, intravenous injection of mc13 cells result in muscle regeneration and partial restoration of dystrophin in mdx mice. Transplantation of mc13 cells engineered to secrete osteogenic protein differentiate in osteogenic lineage and accelerate healing of a skull defect in SCID mice. Taken together, these results suggest the isolation of a population of muscle-derived stem cells capable of improving both muscle regeneration and bone healing.

The potential role of PDGF, IGF-1, TGF-beta expression in idiopathic pulmonary fibrosis

OBJECTIVE

To identify the role of cytokines involved in the development of lung fibrosis in patients with idiopathic-pulmonary fibrosis (IPF).

METHODS

Proteins and gene expression of platelet-derived growth factor (PDGF)-A and -B, insulin-like growth factor 1 (IGF-1), and transforming growth factor beta (TGF-beta) were measured in alveolar macrophages and open lung biopsies from patients with IPF using immunohistochemistry (IHC) and in situ hybridization (ISH).

RESULTS

In specimens of bronchoalveolar lavage fluid (BALF), PDGF-A, PDGF-B, IGF-1, TGF-beta were localized in alveolar macrophages. Evaluation of open lung biopsies from patients with IPF showed that IGF-1 was prominently present in pulmonary vessel walls in fibrotic lesions. PDGF and TGF-beta proteins were localized to hyperplastic bronchio-alveolar epithelial cells, alveolar macrophages, fibroblasts, vascular smooth muscle and endothelial cells. Our in situ hybridization results were consistent with that of immunohistochemistry except that PDGF-A and TGF-beta mRNA transcripts were not detected in bronchoalveolar epithelial cells.

CONCLUSION

These observations suggest that (1) alveolar macrophages play key roles not only in inflammation but also in the fibrotic process by releasing PDGF, IGF-1 and TGF-beta; (2) IGF-1 could be responsible for angiogenesis in IPF; (3) PDGF, TGF-beta are associated with fibroplasia and the deposition of extracellular matrix, as well as vessel remodeling and epithelial cell repopularization.

[Conformity of cancerous diagnosis of serum-fluorimetry under the influence of carotenoid fluorescence]

We observed that carotenoid had sensitization for fluorescence of porphyrin as cancerous diagnostic technology was applied in clinic by serum-fluorimetry. The Forster theory was used in order to analyse sensitized fluorescence between carotenoid and porphyrin in this paper. Transfer characteristic between energy donor and energy acceptor was calculated and discussed its influence on cancerous diagnosis.

[Advances in diagnosis and treatment of ectopic pregnancy during the past ten years]

OBJECTIVE

To investigate the changes of diagnosis and treatment of ectopic pregnancy (EP) during the past ten years.

METHODS

Medical records of 1,970 cases with EP seen in our hospital from Jan. 1987 to Dec. 1996 were collected and analyzed retrospectively.

RESULTS

(1) The incidence of EP increases from 1.0 per 42.4 labours during 1987-1988 to 1.0 per 6.6 labours in 1995-1996. (2) Diagnosis was confirmed more by television laparoscopy, transvaginal ultrasonography and sensitive human chorionic gonadotropin-beta subunit assay rather than loparotomy and with a shorter period, (6.5 +/- 0.7) days in 1987-1988 versus (3.7 +/- 0.2) days in 1995-1996. (3) The choice of treatment was more conservative or through laparoscopic surgery than abdominal salpingectomy. (4) The success rate of conservative surgery expectant management reached 100.0% and medical treatment with a variety of choices around 80.0%-85.%.

CONCLUSIONS

Although the incidence of EP increased, with the improvement of diagnostic approaches, patients were detected at an earlier stage and possible to be treated more conservatively.

The use of adeno-associated virus to circumvent the maturation-dependent viral transduction of muscle fibers

Muscle-based gene therapy using adenovirus, retrovirus, and herpes simplex virus has been hindered by viral cytotoxicity, host immune response, and the maturation-dependent viral transduction of muscle fibers. The development of new mutant vectors has greatly reduced the toxicity and the immune rejection problems, but the inability of viral vectors to penetrate and transduce mature myofibers remains an important issue. Research has been focused on the characterization of barriers to viral transduction in mature myofibers to develop strategies to circumvent the maturation-dependent viral transduction of myofibers. Here, we report that adeno-associated virus (AAV) can be used to overcome the maturation-dependent viral transduction of myofibers. We have investigated by which mechanism AAV can penetrate and efficiently transduce mature muscle fibers, and have shown that this viral vector is not blocked by the basal lamina and that AAV transduction of myofibers is independent of myoblast mediation. Although AAV can efficiently transduce mature myofibers, a differential transduction is still observed among the different types of myofibers that correlates with the expression of the heparan sulfate proteoglycan receptors, the muscle maturity, the number of viral particles used, and the time postinjection. The identification of the mechanisms by which AAV transduces mature myofibers will help in the development of strategies to achieve an efficient muscle-based gene therapy for inherited and acquired diseases.

Spontaneous improvement in reduced vasodilatory capacity in major cerebral arterial occlusive disease

Reduced vasodilatory capacity resulting from occlusive lesions of the major cerebral arteries may return to normal without surgical revascularisation. We aimed to determine prospectively the frequency and predictors of recovery of impaired haemodynamics as demonstrated by acetazolamide (ACZ) reactivity on single-photon emission computed tomography (SPECT). Vasoreactivity was measured by (123)I-IMP SPECT with an ACZ challenge, in 37 medically treated patients with unilateral occlusive disease of the internal carotid or middle cerebral artery at an interval of 1-2 years. Each ACZ challenge test was analysed semiquantitatively by calculating the degree of increase in cerebral blood flow (CBF) asymmetry after ACZ administration (DeltaAI). Vasodilatory capacity was abnormal initially in 20 patients (65 %); eight of whom (40 %) exhibited spontaneous normalisation on follow-up. Although the baseline characteristics did not differ significantly between patients with or without increase in reactivity, logistic regression analysis revealed that the initial DeltaAI (P < 0.05) and the type of vascular lesion (stenosis or occlusion) (P < 0.05) correlated significantly with a return towards normal of reduced ACZ reactivity. Spontaneous improvement of impaired vasodilatory capacity may not be a rare phenomenon. We found that mild reduction in the initial ACZ reactivity and a stenosis, but not complete occlusion, were independent factors contributing to normalisation of impaired cerebral haemodynamics.

[The potential role of cytokine expression and its relation to angiogenesis in idiopathic pulmonary fibrosis]

OBJECTIVE

The expression of insulin-like growth factor (IGF)-I and platelet-derived growth factor (PDGF) in open lung biopsies from patients with idiopathic pulmonary fibrosis (IPF) was studied to investigate their precise role in the development of fibrosis in IPF.

METHODS

The distribution and expression of IGF-I and PDGF were examined in lung sections of IPF patients with antibodies and cDNA probes of IGF-I and PDGF by immunohistochemistry and in situ hybridization.

RESULTS

IGF-I was predominantly localized in vascular smooth muscle cells and vascular endothelial cells of newly formed vessels in IPF. Smooth muscle cells of pulmonary arteries which underwent hypertrophy and hyperplasia strongly expressed IGF-I (+ + +). Type II cells, alveolar macrophages, and interstitial cells were also stained with anti-IGF-I, but with lesser intensity (+). PDGF-AA and BB were localized in hyperplastic bronchio-alveolar epithelial cells and interstitial fibroblasts (+ + +). Alveolar macrophages, vascular endothelial cells and smooth muscle cells were also stained positive (+ +).

CONCLUSION

IGF-I and PDGF promote angiogenesis and vascular smooth muscle cell hypertrophy and hyperplasia, which contribute to the progression of fibrosis in IPF. IGF-I and PDGF are also involved in reepithelization and fibroproliferation in IPF through interaction with mesenchymal cells.

Extended tropism of an adenoviral vector does not circumvent the maturation-dependent transducibility of mouse skeletal muscle

BACKGROUND

Efficient adenoviral gene delivery to mature skeletal muscle has been hindered by different factors. The low levels of adenoviral attachment receptor (CAR) that have been reported in this tissue may be a limiting factor. Therefore, adenoviral transduction of mature muscle may be improved by extending the tropism of the adenoviral vectors to attachment receptors that are highly expressed in mature myofibers. In this study, we have investigated whether an extended tropism adenoviral vector which additionally attaches to the broadly expressed heparan-containing receptors (AdPK) can bypass the maturation-dependent adenoviral transducibility of mouse skeletal muscle.

METHODS

The adenoviral vector AdPK carrying the LacZ gene was evaluated as a gene delivery vehicle in mouse skeletal muscle at different maturities in vitro and in vivo. The viral transduction efficiencies were determined by histochemical and ONPG analysis of the beta-galactosidase activity level.

RESULTS

Higher transduction efficiencies were detected in immature muscle from normal mice, and in mature muscle from merosin-deficient dy/dy mice (carrying myofibers with an impaired extracellular matrix) and dystrophin-deficient mdx mice (showing a high level of myoblast activity) when compared to mature muscle from normal mice.

CONCLUSION

Despite the enhanced attachment characteristics, the extended tropism adenoviral vector is, similarly to the wild-type adenoviral vector in previous studies, still hindered by both a protective extracellular matrix and the diminished myoblast-mediation in mature muscle.

Loss of heterozygosity, by mitotic gene conversion and crossing over, causes strain-specific adenine mutants in constitutive diploid Candida albicans

Molecular evidence is provided in this paper to elucidate a long-standing intriguing phenomenon in fungal genetics: that many natural isolates of the constitutive diploid organism Candida albicans yield strain-specific, recessive mutants at a reproducible frequency that is as high as a few percent of the surviving cells after exposure to UV irradiation or other mutagens. Southern hybridization analysis and DNA sequence data indicated that C. albicans CA12, a clinical isolate, is heterozygous for the ADE2 gene, carrying one functional and one null allele. Sequence analysis of the null allele revealed the presence of a 1.3 kb deletion, which locates between two AATC repeats and spans the promoter and coding regions of the gene. The adenine auxotrophic mutants, which were readily isolated after UV irradiation of C. albicans CA12, were proved to be the segregants of mitotic recombination as they remained as diploid, not hemizygous or haploid, cells and were homozygous for ade2. Analysis of reciprocal products of the mitotic recombination detected that the process of loss of heterozygosity was mediated by mitotic crossing over (reciprocal exchange of genetic information) as well as gene conversion (non-reciprocal exchange of genetic information).

Secondary structure peptide mimetics: design, synthesis, and evaluation of beta-strand mimetic thrombin inhibitors

Constrained dipeptide mimetic templates were designed to mimic the secondary structure of peptides in a beta-strand conformation. Two templates corresponding to the D-Phe-Pro portion of the thrombin inhibitor D-Phe-Pro-ArgCH2Cl were synthesized and converted into nine alpha-ketoamide and alpha-ketoheterocycle inhibitors of thrombin. Additionally, a template corresponding to L-Phe-Pro was synthesized and converted to a thrombin inhibitor. The in vitro inhibition of thrombin by these compounds was determined, and those corresponding to the D-Phe-Pro were found to be more potent inhibitors than the L-Phe-Pro mimetic. The alpha-ketoamides were found to be more potent than the alpha-ketoheterocycles but had much slower on rates. By comparison of a series of alpha-ketoamide analogues, it is apparent that the there is a preference for binding of bulky hydrophobic substituents in the P' portion of the thrombin active site. Three of the inhibitors (MOL098, MOL144, and MOL174) were screened against a series of coagulation and anticoagulation enzymes and found to be selective for inhibition of the coagulation enzymes. Two of the inhibitors were tested in in vitro models of intestinal absorption and found to have low absorption potential. The compounds were then tested in vivo in both rats and primates, and one of them (MOL144) was approximately 25% absorbed in both species. This study has delineated the synthesis of constrained dipeptide beta-strand mimetics and validated the potential for compounds of this type as potent thrombin inhibitors and possible drug leads.

[The effect of age on the regional blood flow of neck of femur in normal Chinese]

This study aimed to assess the effect of age on the regional blood flow of neck of femur in normal Chinese. 133Xe washout method was adopted. The result showed that the femur regional blood flow of normal Chinese decreased slowly with the increase of their age. The relation between age and femur blood flow might be expressed as F = -0.042Y + 9.01(F refers to blood flow, Y refers to age). The average femur regional blood flow of normal Chinese was 7.37 +/- 0.62 ml.(100 g.min)-1 for 21-40 years old. The authors suggest this result can be considered to stand for regional femur blood flow of young healthy adults.

[The potential role of cytokines expression in idiopathic pulmonary fibrosis]

OBJECTIVE

To investigate the protein and gene expression in bronchoalveolar lavage cells and open lung biopsies from patients with IPF.

METHODS

The immunohistochemical methods were used to analyze the expression of PDGF, TGF-beta in bronchoalveolar lavage cells of patients with IPF. For open lung biopsies, both immunohistochemistry and in situ hybridization were used.

RESULTS

In specimens of bronchoalveolar lavage fluid, PDGF-AA, PDGF-BB, TGF-beta were localized to alveolar macrophages in patients with IPF. Though there were no differences between IPF and sarcoidosis in terms of the staining intensity (2.5 - 3.0) or number of positive cells 81% - 90%, the number of such cells were less in the control (0 - 1.7, 25% - 32% respectively). Evaluation of open lung biopsies from patients with IPF showed that PDGF, TGF-beta proteins were localized to hyperplastic bronchio-alveolar epithelial cells (2.4 - 3.7, in control 0), alveolar macrophages (2.9 - 3.7, in control 0.8 - 1.3), fibroblasts (3.0 - 3.6, in control 2.7 - 2.8), vascular smooth muscle cells, vascular endothelial cells, and fibroblast-like cells surrounding pulmonary vessels (2.7 - 4.0, in control 2.1 - 2.9). In situ hybridization results were consistent with that of immunohistochemistry except that PDGF and TGF-beta mRNA transcripts were not detected in bronchio-alveolar epithelial cells. In control lungs, however, both ISH and IHC revealed that PDGF and TGF-beta were only present in the pleura and in fibroblast-like cells surrounding pulmonary vessels.

CONCLUSIONS

PDGF and TGF-beta, which interplay with pulmonary mesenchymal cells, are involved in fibroplasia and deposition of extracellular matrix as well as angiogenesis and epithelial cell repopularization.

[Clinical significance of detection of IL-2R for non-small cell lung cancer.]

BACKGROUND

To explore the clinical significance of SIL-2R of serum and IL-2R expression of cancer tissue in non-small cell lung cancer.

METHODS

SIL-2R levels in the serum and IL-2R expression in cancer tissues were detected in 42 non-small cell lung cancer by ELISA and immunohistochemistry respectively.

RESULTS

Serum SIL-2R level was significantly higher in lung cancer group than that in normal control group ( P < 0. 05) , and significantly higher in stage III, IV disease than that in stage I, II disease ( P < 0. 05) , but it was not associated with histological classification of the cancer ( P > 0. 05) . IL-2R expression was significantly higher in lung cancer tissue than that in normal lung tissue ( P < 0. 05) and was significantly higher in stage III, IV cancer than that in stage I, II cancer ( P < 0. 05) . But it was not related to cancer types ( P > 0. 05) .

CONCLUSIONS

The results suggest that detection of serum SIL-2R and IL-2R expression of the cancer tissue might be useful to predict stages of cancer and monitor the prognosis of patients with lung cancer.