A low-dimensional deformation model for cancer cells in flow

A low-dimensional parametric deformation model of a cancer cell under shear flow is developed. The model is built around an experiment in which MDA-MB-231 adherent cells are subjected to flow with increasing shear. The cell surface deformation is imaged using differential interference contrast microscopy imaging techniques until the cell releases into the flow. We post-process the time sequence of images using an active shape model from which we obtain the principal components of deformation. These principal components are then used to obtain the parameters in an empirical constitutive equation determining the cell deformations as a function of the fluid normal and shear forces imparted. The cell surface is modeled as a 2D Gaussian interface which can be deformed with three active parameters: H (height), σ(x) (x-width), and σ(y) (y-width). Fluid forces are calculated on the cell surface by discretizing the surface with regularized Stokeslets, and the flow is driven by a stochastically fluctuating pressure gradient. The Stokeslet strengths are obtained so that viscous boundary conditions are enforced on the surface of the cell and the surrounding plate. We show that the low-dimensional model is able to capture the principal deformations of the cell reasonably well and argue that active shape models can be exploited further as a useful tool to bridge the gap between experiments, models, and numerical simulations in this biological setting.

Reutilization of immobilized fungus Rhizopus sp. LG04 to reduce toxic chromate

AIMS

Most of the researches investigating immobilized fungi in chromate [Cr(VI)] bioremediation have used dead cells to adsorb Cr(VI). Therefore, the aim was to identify a Cr(VI)-reducing fungus with the ability of reducing the toxic Cr(VI) into the much less toxic Cr(III) and to apply the immobilized living fungus in continual reduction of Cr(VI).

METHODS AND RESULTS

Cr(VI) reduction occurred using both free fungi and immobilized living Rhizopus sp. LG04. The Cr(VI) bioreduction by the free fungi was achieved mainly by bioreduction coupled with a small amount of biosorption on the cell surfaces. LG04 spores immobilized with 3% polyvinyl alcohol and 3% sodium alginate produced the most stable and efficient biobeads. When the LG04 biobeads were washed and transferred into fresh medium containing 42 mg l(-1) of Cr(VI), the biobeads could be reused to reduce Cr(VI) for more than 30 cycles during an 82-day operation period. Interestingly, as the cycles increased, the time required for complete reduction stabilized at approximately 2·5 days, which was faster than that obtained using the free fungi (4·5 days). The pH value of the solution decreased from 6·60 ± 0·10 to 3·85 ± 0·15 after each reduction cycle, which may be because the metabolic products of the fungus changed the environmental pH or because there was an accumulation of the organo-Cr(III) complex.

CONCLUSIONS

The results indicate that using the immobilized living fungus for the removal of Cr(VI) has the advantages in being stable, long-term treatment, easy to re-use and less biomass leakage.

SIGNIFICANCE AND IMPACT OF THE STUDY

To our knowledge, this study reports the first successful use of immobilized living Rhizopus for the repeated reduction of Cr(VI).

Inclusion of the female condom in a male condom-only intervention in the sex industry in China: a cross-sectional analysis of pre- and post-intervention surveys in three study sites

OBJECTIVES

To describe female condom (FC) use, male condom (MC) use and overall levels of protected sex before, during and after FC education and promotion (using the original prototype FC) combined with MC promotion among female sex workers in three rural or small urban settings in southern China.

STUDY DESIGN

The 1-year FC intervention was conducted by local health workers through outreach to establishments where sex work is conducted. Three serial cross-sectional surveys were conducted in each study town before, during and after the intervention along with process documentation throughout the intervention period.

METHODS

Cross-sectional data from pre-intervention (baseline) and 6-month and 12-month post-intervention surveys from three study sites are used in a descriptive comparison of the context of the sex industry, outreach in two phases of intervention, and FC adoption after the intensive intervention phase in each site.

RESULTS

Approximately 75-80% of eligible women working in sex establishments, varying from 74 to 155 participants for each survey, were recruited from three study sites. After introduction and promotion of the FC along with the MC during the community public health intervention, between one-fifth and one-half of the study participants had tried the FC in the three study sites by the time of the 6-month and 12-month cross-sectional surveys. Among them, 10-30% had used the FC more than once. FC awareness increased following the intervention with much less variation across the three study sites. At baseline, 31-54% of participants across the three sites reported 100% protected sex in the last 30 days with all types of partners. At one of the sites with relatively low MC use before the intervention, the proportion of women reporting 100% protected sex in the last 30 days increased by 15%, and the proportion reporting nil protected sex in the last 30 days decreased by 13% between baseline and 12-month post-intervention surveys. More complex profiles of FC and MC use and protected sex were shown at the other two study sites, where a higher level of protection had been reached before the project started.

CONCLUSIONS

Different levels of FC adoption were identified after the 1-year FC promotion intervention through outreach to sex establishments. The input, output and outcomes of the intervention may be associated with women's demographic and risk characteristics, the local capacities of intervention staff, and other contextual factors. Further analysis of these factors will help establish the role of the FC in increasing protected sex, and provide insight into how to achieve greater FC use.

Ultrasound-guided percutaneous cryotherapy of hepatocellular carcinoma

BACKGROUND

Reports on percutaneous cryoablation to treat patients with HCC are sparse in the medical literature. This study aimed to determine the safety and efficacy of percutaneous cryotherapy for unresectable or recurrent hepatocellular carcinoma (HCC).

METHODS

The results of 40 patients with unresectable HCC and 26 patients with recurrent HCC treated with ultrasound-guided percutaneous cryotherapy from January 2006 to June 2009 were retrospectively analyzed.

RESULTS

We used percutaneous cryotherapy to treat 76 tumors in 40 patients with unresectable and 76 tumors in 26 patients with recurrent HCC. The size of the tumors was 2.8 ± 1.7 cm (mean ± S.D.). The mean number of treatment sessions for unresectable and recurrent HCC were 1.7 and 1.4, respectively. All cryotherapy procedures were technically successful. No procedure-related death was observed. The overall complication rate was 12.1%. Patients with unresectable HCC had 1-, and 3-year overall survival rates of 81.4%, and 60.3%, while the disease-free survival rates at 1 year and 3 years were 67.6% and 20.8%, respectively. Patients with recurrent HCC had 1-, and 3-year overall survival rates of 70.2%, and 28.8%, while the disease-free survival rates at 1 year and 3 years were 53.8% and 7.7%, respectively.

CONCLUSION

Ultrasound-guided percutaneous cryotherapy was safe and efficacious in the treatment of unresectable and recurrent HCC. Further randomized trials are needed to compare the safety and efficacy of cryotherapy with other forms of percutaneous treatment so that an unbiased therapeutic strategy can be devised.

Adrenomedullin regulates sperm motility and oviductal ciliary beat via cyclic adenosine 5'-monophosphate/protein kinase A and nitric oxide

Cilium and flagellum beating are important in reproduction and defects in their motion are associated with ectopic pregnancy and infertility. Adrenomedullin (ADM) is a polypeptide present in the reproductive system. This report demonstrates a novel action of ADM in enhancing the flagellar/ciliary beating of human spermatozoa and rat oviductal ciliated cells. At the concentration found in the seminal plasma, it increases the progressive motility of spermatozoa. ADM binds to its classical receptor, calcitonin receptor-like receptor/receptor activity-modifying protein complex on spermatozoa. ADM treatment increases the protein kinase A activities, the cyclic adenosine monophosphate, and nitric oxide levels of spermatozoa and oviductal cells. Pharmacological activators and inhibitors confirmed that the ADM-induced flagella/ciliary beating was protein kinase A dependent. Whereas nitric oxide donors had no effect on sperm motility, they potentiated the motility-inducing action of protein kinase A activators, demonstrating for the first time the synergistic action of nitric oxide and protein kinase A signaling in flagellar/ciliary beating. The ADM-induced motility enhancement effect in spermatozoa also depended on the up-regulation of intracellular calcium, a known key regulator of sperm motility and ciliary beating. In conclusion, ADM is a common activator of flagellar/ciliary beating. The study provides a physiological basis on possible use of ADM as a fertility regulation drug.

Downregulation of the Novel Candidate Tumor Suppressor Gene NCOR2/SMRT in Human Breast Cancer Progression

Background: We recently described a number of DNA copy number changes that differentiated low grade ductal carcinoma in situ (DCIS) lesions with and without associated invasive carcinoma. One of the invasion-associated candidate genes was Nuclear Corepressor 2/Silencing Mediator of Retinoid and Thyroid Receptors (NCOR2/SMRT). This gene is a component of a repressing nuclear receptor complex and a mediator of ER activity. It facilitates recovery from DNA double strand breaks. Previous studies showed that downregulation of the gene was associated with transformation of non-Hodgkin lymphomas.Materials and Methods: Genomic DNA was extracted from microdissected paraffin sections of formalin fixed low grade DCIS lesions with an invasive component (n=42), as well as morphologically similar DCIS lesions without associated invasion within at least 5 years (n=38). Comparative PCR was performed with GAPDH as the reference gene. In addition, we assayed tissue microarrays (TMAs) by immunohistochemistry using two anti-Smrt antibodies. Three TMAs included 162 interpretable cases of invasive breast carcinoma from Roswell Park Cancer Institute (RPCI). One additional TMA included 73 interpretable breast cancers from a previously described cohort from Vienna, Austria. Nuclear staining in neoplastic cells was scored as positive, reduced (significantly weaker compared to admixed benign cells), and negative. Ncor2/Smrt expression was correlated with various patho-biologic variables.Results: Allelic loss of NCOR2/SMRT was observed in 79% (33/42) of DCIS lesions with associated invasion, but in only 26% (10/38) of pure DCIS cases (p<0.01). In the RPCI breast cancer cohort, nuclear Ncor2/Smrt protein was absent or downregulated in 73% (119/162) of tumors. In the Vienna cohort, there was no or markedly reduced nuclear staining in 48% (35/73) of cases. In both cohorts, loss of nuclear reactivity was more common in ER-negative breast cancers. In the Vienna series, Ncor2/Smrt loss was more frequent in PR-negative tumors as well. In the RPCI cohort, Ncor2/Smrt downregulation was more common in ductal (81%, 109/135) than in lobular (37%, 10/27) carcinomas. Neither series showed a significant association between Ncor2/Smrt expression and tumor grade or HER2/neu status.Discussion: Allelic loss of NCOR2/SMRT was significantly more common in DCIS lesions associated with stromal invasion. In invasive tumors, the protein downregulation rate was between 48% and 73%. The gene was more commonly downregulated in ER-negative carcinomas, consistent with its role as a modulator of ER function. Our data provide new evidence that NCOR2/SMRT may play an important part in early breast cancer progression.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3150.

Population pharmacokinetic modeling for intravenous temsirolimus and sirolimus metabolite in subjects with various solid tumors

2522

Background: Temsirolimus (TEMSR) is an mTOR inhibitor approved for treatment of patients with advanced renal cell carcinoma, and under development for relapsed/refractory mantle cell lymphoma (MCL). In MCL, TEMSR showed a dose-related increase in median progression-free survival [4.8 vs. 3.4 mo] and objective response rate [22% vs 6%] for 175 mg x 3 wks then 75 or 25 mg weekly regimens (175/75-mg and 175/25-mg), respectively. We aim to characterize the population pharmacokinetic exposure, covariate influence, and differences afforded by these regimens. Methods: Nonlinear mixed-effects models of TEMSR and sirolimus (SIR; major active metabolite) blood concentrations were defined in healthy subjects and patients. Modeling for TEMSR employed a 4-compartment model with saturable distribution to red cells and peripheral tissue, and modeling for SIR utilized a linear 2- compartment model with factor for dose. Covariates included demographic factors, clinical labs, and disease condition. Following validation, simulations with variability were used to evaluate effects of covariates on exposure. Results: Final datasets comprised 1342 observations from 150 subjects (TEMSR) and 1648 observations from 279 subjects (SIR). In a typical patient (56-year-old male weighing 76.5 kg), disease affected TEMSR clearance (62.4 L/h in MCL, 92.1 L/h in breast cancer vs. 112 L/h for other subjects). Dose, single vs. multiple, and body weight affected SIR apparent clearance. Simulations for the 175/75-mg regimen indicate that significant covariates yield only modest differences on blood exposures. For MCL (175/75-mg regimen), TEMSR Cmax (week 3) was 2574 ng/mL and SIR Ctrough (week 6) was 10.7 ng/mL. AUC for the 75-mg maintenance arm was ∼2.3-fold (TEMSR) and ∼3.5-fold higher (SIR) than respective values of the 25-mg arm. Correlation of average AUC to clinical response was not apparent. Conclusions: No significant differential effects were observed for age, gender, race, or hepatic and renal laboratory measures. Covariates of disease, while significant, have only modest effects on the exposure profile. Higher clinical responses observed with the 175/75-mg regimen as compared with the 175/25-mg regimen may critically derive from differences in exposure.

[Table: see text]

Preoperative assessment and staging of hilar cholangiocarcinoma with 16-multidetector computed tomography cholangiography and angiography

BACKGROUND/AIMS

To evaluate prospectively the preoperative use of 16-multidetector computed tomography (MDCT) with cholangiography and angiography in determining the resectability of hilar cholangiocarcinoma.

METHODOLOGY

From January 2002 to January 2008, 75 consecutive patients with hilar cholangiocarcinoma underwent preoperative MDCT with cholangiography and angiography. 3D images of the portal vein, hepatic artery, and bile ducts were created and viewed simultaneously. The accuracy of MDCT with cholangiography and angiography was determined by comparison with intraoperative and pathologic findings.

RESULTS

All patients tolerated the CT imaging well and without serious complication. The sensitivity, specificity, and accuracy rates were 92.9%, 100%, and 96% for portal vein invasion and 83.3%, 100%, and 93.3% for hepatic arterial invasion. The accuracy rate of longitudinal tumor extension, using the modified Bismuth-Corlette classification, was 96%. The sensitivity, specificity, and accuracy of prediction of resectability were 95.7%, 82.1%, and 90.7%, respectively.

CONCLUSIONS

Preoperative MDCT with cholangiography and angiography gave a good assessment of the degree of biliary and vascular involvement of hilar cholangiocarcinoma. It also accurately predicted resectability.

Dominant local binary patterns for texture classification

This paper proposes a novel approach to extract image features for texture classification. The proposed features are robust to image rotation, less sensitive to histogram equalization and noise. It comprises of two sets of features: dominant local binary patterns (DLBP) in a texture image and the supplementary features extracted by using the circularly symmetric Gabor filter responses. The dominant local binary pattern method makes use of the most frequently occurred patterns to capture descriptive textural information, while the Gabor-based features aim at supplying additional global textural information to the DLBP features. Through experiments, the proposed approach has been intensively evaluated by applying a large number of classification tests to histogram-equalized, randomly rotated and noise corrupted images in Outex, Brodatz, Meastex, and CUReT texture image databases. Our method has also been compared with six published texture features in the experiments. It is experimentally demonstrated that the proposed method achieves the highest classification accuracy in various texture databases and image conditions.

Syntheses of optically pure, conformationally constrained, and highly hydrophobic unusual amino acids: 2-amino-3, 3-diarylpropionic acids*

A series of optically pure, conformationally constrained, and highly hydrophobic unusual aromatic amino acids, 2-amino-3,3-diarylpropionic acids, were synthesized via asymmetric 1,4-Michael addition reaction/azidation reactions in seven steps with overall yields of 20-30%.

Role of retinoic acid inducible gene-I in human metapneumovirus-induced cellular signalling

Human metapneumovirus (HMPV) is a recently discovered pathogen that causes a significant proportion of respiratory infections in young infants, the elderly and immunocompromised patients. Very little is known regarding the cellular signalling elicited by this virus in airway epithelial cells, the target of HMPV infection. In this study, we investigated the role of the RNA helicases retinoic acid inducible gene-I (RIG-I) and melanoma differentiation-associated gene-5 (MDA-5) as the main pattern recognition receptors (PRRs) involved in viral detection and subsequent expression of proinflammatory and antiviral genes. HMPV infection readily induced RIG-I and MDA-5 gene and protein expression in A549 cells, a type II-like alveolar epithelial cell line. Expression of dominant-negative (DN) RIG-I or downregulation of RIG-I gene expression using small interfering RNA (siRNA) significantly decreased HMPV-induced beta interferon (IFN-beta), interleukin (IL)-8 and RANTES gene transcription, by inhibiting viral-induced activation of nuclear factor (NF)-kappaB and interferon regulatory factor (IRF), leading to enhanced viral replication. On the other hand, MDA-5 did not seem to play a significant role in HMPV-induced cellular responses. Mitochondrial antiviral signalling protein (MAVS), an adaptor protein linking both RIG-I and MDA-5 to downstream activation of IRF-3 and NF-kappaB, was also necessary for HMPV-induced cellular signalling. Expression of a DN MAVS significantly reduced IFN-beta and chemokine gene transcription, by inhibiting NF-kappaB- and IRF-dependent gene transcription, in response to HMPV infection. Our results show that HMPV activates the RIG-I-MAVS signalling pathway in airway epithelial cells, leading to the expression of important proinflammatory and antiviral molecules involved in the innate immune response to viruses.

Markers of angiogenesis in cervical cancer: A Gynecologic Oncology Group study

5536

Background: Extensive tumor angiogenesis has correlated with poorer progression-free and overall survival in cervical cancer; however, specific markers of angiogenesis have not been studied prospectively. Methods: Cervical cancer patients with high-risk features on radical hysterectomy were eligible for randomization to adjuvant pelvic irradiation ± radiosensitizing platinum. Following central pathology review, formalin-fixed, paraffin-embedded tumors were sectioned into 4-micron specimens. Semi-quantitative immunohistochemisty (IHC) was performed using previously validated antibodies against mutant p53 (mp53), vascular endothelial growth factor (VEGF), thrombospondin-1 (TSP-1), and endothelial markers CD 31 and CD 105. Tumoral histoscores (HS) were calculated for mp53 and VEGF using the formula: [% cells positive × (intensity +1)], with a 5% threshold for positivity and intensity ranging 1–4+ (3+ = intensity of positive control). Intensity scores (0–4+) were assigned to TSP-1 specimens referencing the positive control (3+). MVD “hotspots” were counted in a 20X high-power field. HS and MVD counts were considered as continuous variables and TSP-1 intensity as an ordinal variable. Associations between markers were determined by Pearson’s and Spearman’s correlation tests, between markers and clinico-pathologic variables by Wilcoxon rank test, and between markers and survival by Cox regression modeling. Results: One hundred seventy-six specimens were analyzed. Acquisition of mp53 and increased VEGF expression were associated with increased MVD assessed by both CD31 (p=0.08 and p=0.002, respectively) and CD105 (p=0.02 and p=0.012, respectively). Statistically significant associations between markers and high-risk pathologic factors included: low-level TSP-1 and high CD-105 counts with lymph node metastases; high VEGF scores with advanced stage, non-squamous histologic subtype, and depth of tumor invasion; and high CD 31 counts with parametrial metastases. Survival analysis is currently being performed. Conclusions: Angiogenesis occurs early in cervical carcinogenesis, and may be a rational target for biologic therapy in cervical cancer.

No significant financial relationships to disclose.

Superinfection of Laodelphax striatellus with Wolbachia from Drosophila simulans

Wolbachia are maternally inherited, intracellular alpha-proteobacteria that infect a wide range of arthropods. They manipulate the reproduction of hosts to facilitate their spread into host populations, through ways such as cytoplasmic incompatibility (CI), parthenogenesis, feminization and male killing. The influence of Wolbachia infection on host populations has attracted considerable interest in their possible role in speciation and as a potential agent of biological control. In this study, we used both microinjection and nested PCR to show that the Wolbachia naturally infecting Drosophila simulans can be transferred into a naturally Wolbachia-infected strain of the small brown planthopper Laodelphax striatellus, with up to 30% superinfection frequency in the F(12) generation. The superinfected males of L. striatellus showed unidirectional CI when mated with the original single-infected females, while superinfected females of L. striatellus were compatible with superinfected or single-infected males. These results are, to our knowledge, the first to establish a superinfected horizontal transfer route for Wolbachia between phylogenetically distant insects. The segregation of Wolbachia from superinfected L. striatellus was observed during the spreading process, which suggests that Wolbachia could adapt to a phylogenetically distant host with increased infection frequency in the new host population; however, it would take a long time to establish a high-frequency superinfection line. This study implies a novel way to generate insect lines capable of driving desired genes into Wolbachia-infected populations to start population replacement.

Metabolism of the analgesic drug ULTRAM (tramadol hydrochloride) in humans: API-MS and MS/MS characterization of metabolites

1. Metabolism of the analgesic agent tramadol hydrochloride has been investigated after a single oral administration of tramadol to three male volunteers (100 mg/subject), and a urine pool (4-12h) was obtained. 2. Unchanged tramadol and a total of 23 metabolites, consisting of 11 Phase I metabolites (M1-11) and 12 conjugates (seven glucuronides, five sulphates), were profiled, characterized and tentatively identified in urine on the basis of API ionspray-MS and MS/MS data. 3. Of the metabolites, five (M1-5) had been previously identified. 4. The metabolites were formed via the following six metabolic pathways: (1) O-demethylation, (2) N-demethylation, (3) cyclohexyl oxidation, (4) oxidative N-dealkylation, (5) dehydration and (6) conjugation. 5. Pathways 1-3 appear to be major routes, forming seven O-desmethyl/N-desmethyl and hydroxycyclohexyl metabolites. 6. Pathways 1-3 in conjunction with pathway 6 produced seven glucuronides along with five sulphates. 7. In addition, the in vitro metabolism of tramadol was conducted using a human liver microsomal fraction in the presence of an NADPH-generating system. Unchanged tramadol (82% of the sample) plus eight metabolites (M1, M2, M4-6, tramadol-N-oxide (M31), OH-cyclohexyl-M1 (M32) and dehydrated tramadol-N-oxide), were profiled and tentatively identified on the basis of MS and MS/MS data.

Differential tramadol and O-desmethyl metabolite levels in brain vs. plasma of mice and rats administered tramadol hydrochloride orally

OBJECTIVE

To investigate a possible differential brain uptake of tramadol vs. its major metabolite (O-desmethyl tramadol; M1) in mice and rats.

METHODS

An extraction and measurement technique (gas chromatograph equipped with a nitrogen phosphorus detector) was used to measure plasma and brain levels of tramadol and M1 at intervals 10-300 min after oral dosing of tramadol hydrochloride to mice and rats.

RESULTS

For all doses of tramadol administered (5, 10, 20, or 40 mg/kg), tramadol and M1 plasma levels were greatest 10 min after dosing: in mice, peak tramadol plasma levels were 47.75-736.72 ng/mL and peak M1 levels were 75.30-1084.92 ng/mL; in rats, peak tramadol plasma levels were 185.03-455.81 ng/mL and peak M1 levels were 106.74-455.70 ng/mL. Tramadol brain levels were also greatest 10 min after dosing. In mice, peak tramadol brain levels were 226.42-1847.46 ng/g. Peak M1 levels (72.17-572.97 ng/g) occurred 20-60 min after dosing. In rats, peak tramadol brain levels were 258.50-1777.37 ng/g and peak M1 levels were 80.35-289.60 ng/g. In mice, the ratio of tramadol/M1 in plasma was 0.5-1.0 throughout the measurements, whereas the ratio in brain was about 10 at 10 min and about 2 from 20 to 50 min. In rats, the ratio of tramadol/M1 in plasma was 0.5-1.5, whereas the ratio in brain was about 15 at 10 min and about 4-7 thereafter.

CONCLUSION

In mice and rats, there appears to be preferential brain vs. plasma distribution of tramadol over M1.

Concordance between tramadol and dextromethorphan parent/metabolite ratios: the influence of CYP2D6 and non-CYP2D6 pathways on biotransformation

Cytochrome P4502D6 (CYP2D6) activity has been shown to be a determinant of both the pharmacokinetics and pharmacodynamics of tramadol in adults. This study evaluated the association between CYP2D6 activity, as determined by dextromethorphan (DM) urinary metabolite ratio, and tramadol biotransformation in 13 children (7-16 years). CYP2D6 genotype was determined by XL-PCR and PCR/RFLP. Phenotype was assessed by HPLC quantitation of DM and its metabolites from a 12- to 24-hour urine collection following a single oral dose of DM. There was only a modest correlation between tramadol/M1 (metabolite 1) plasma concentration or AUC and the DM/dextrorphan (DX) urinary molar ratio in the study cohort; however, when subjects were segregated based on the number of functional CYP2D6 alleles, a much stronger relationship was observed for subjects with two functional alleles, with essentially no relationship evident in those individuals with one functional allele. Further evaluation of these data suggested that the CYP2D6-mediated metabolite (M1) is formed to a lesser extent, and the formation of the non-CYP2D6 product (M2) is more pronounced in subjects with one versus two functional alleles. Thus, the number of functional CYP2D6 alleles and the availability of alternative cytochromes P450 capable of metabolizing tramadol may explain the poor association between DM, a well-characterized CYP2D6 probe, and tramadol in a population of CYP2D6 extensive metabolizers.

The medicinal action of androgens and green tea epigallocatechin gallate

Unorthodox (non-traditional or alternative) medicinal practices have been expanding very rapidly in western countries. Modern physicians, scientists, and non-traditional medicine practitioners now must join forces to promote evidence-based medicine to benefit patients. Green tea extracts are among the most widely used ancient medicinal agents, while androgens are probably the oldest drugs used in a purified form in traditional Chinese medicine. It is now clear that a specific green tea catechin, (-)epigallocatechin-3-gallate, can modulate the production and biological actions of androgens and other hormones. Modulation of androgenic activity and administration of (-)epigallocatechin-3-gallate may be useful for the treatment of various hormone-related abnormalities, such as benign prostatic hyperplasia, baldness, and acne, as well as androgen-dependent and -independent prostate cancers. (-)Epigallocatechin-3-gallate has also been shown to modulate appetite and control obesity in animals.

Gas chromatographic method using nitrogen-phosphorus detection for the measurement of tramadol and its O-desmethyl metabolite in plasma and brain tissue of mice and rats

A method that allows the measurement of plasma and brain levels of the centrally-acting analgesic tramadol and its major metabolite (O-desmethyl tramadol) in mice and rats was developed using gas chromatography equipped with nitrogen-phosphorus detection (GC-NPD). Plasma samples were extracted with methyl tert.-butyl ether (MTBE) and were injected directly into the GC system. Brain tissue homogenates were precipitated with methanol, the resulting supernatant was dried then acidified with hydrochloric acid. The aqueous solution was washed with MTBE twice, alkalinized, and extracted with MTBE. The MTBE layer was dried, reconstituted and injected into the GC system. The GC assay used a DB-1 capillary column with an oven temperature ramp (135 to 179 degrees C at 4 degrees C/min). Dextromethorphan was used as the internal standard. The calibration curves for tramadol and O-desmethyl tramadol in plasma and brain tissue were linear in the range of 10 to 10000 ng/ml (plasma) and ng/g (brain). Assay accuracy and precision of back calculated standards were within +/- 15%.

Aortic and mitral valve replacement with retrograde perfusion in the beating heart

OBJECTIVE

To estimate the value of aortic valves and combined mitral valve replacement with retrograde perfusion in beating hearts.

METHODS

Continuous retrograde coronary sinus perfusion with beating hearts was used in 83 patients undergoing aortic valve or aortic valve combined with mitral valve replacement, without application of cardioplegia. After aortic valve replacement, the retrograde perfusion was changed to antegrade perfusion for mitral valve replacement or correction of the other deformities (group A). Cold blood cardioplegia solution (15 degrees C) was infused at intervals in 20 cases (group B). The following parameters were tested: lactate, ET, CTn-T and MDA in blood; myocardial ultra-structure; and cardiac rhythm and cardiac output (CO).

RESULTS

All biochemical values increased after cardiopulmonary bypass (P < 0.05-0.01). Empty and beating heart sinus rhythm was maintained in group A. Myocardial ultrastructure did not change significantly. The pump was stopped smoothly as the surgical procedure finished. No postoperative low cardiac output syndrome or arrhythmia was observed. Eight-one patients recovered smoothly, two died from renal failure or infective shock. When the pump stopped, all patients in group B were supported by 5-10 micrograms.kg-1.min-1 dopamine. Transient pacing was used in 9 patients. One patient died from low cardiac output syndrome.

CONCLUSION

This method is a good myocardial protection which simulates physiologic status. It is applicable to aortic valve and combined mitral valve replacement of patients with large heart or heart failure and long time aortic cross-clamping. Ideal clinical effect can be achieved.

Identification and comparison of residues critical for cell-adhesion activities of two neutrophil CD66 antigens, CEACAM6 and CEACAM8

CEACAM6 (CD66c) and CEACAM8 (CD66b) are cell-adhesion proteins on neutrophils that belong to the human carcinoembryonic antigen (CEA) family. CEACAM6 reveals homophilic adhesion and heterophilic adhesion to other CEACAM family antigens including CEACAM8, CEACAM1, and CEA, whereas CEACAM8 exhibits only heterophilic adhesion to CEACAM6. Here, we investigated and compared structural requirements for the homophilic adhesion of CEACAM6 and heterophilic adhesion between CEACAM6 and CEACAM8 at the amino acid level by using CHO transfectants expressing their mutant and chimeric proteins. The NH(2)-terminal domain (N-domain) of CEACAM6 expressed on a CHO cell was suggested to bind the N-domain of CEACAM6 or CEACAM8 on the opposing cell. By homologue-scanning mutagenesis, we found that the locations of the sequences critical for the adhesion of CEACAM6 to itself and to CEACAM8 are overlapped and that they are highly similar but not identical to the locations of the residues previously shown to be essential for the binding of CEACAM antigens to Opa proteins of pathogenic NEISSERIAE: Our findings imply that subtle differences in the N-domain sequences determine the specificity of the CEACAM antigens on neutrophils for interaction with the same or different CEACAM antigens and the bacterial proteins.

Hypolipidemic effects of selective liver X receptor alpha agonists

Recently, a number of nuclear receptors have been identified as key regulators of cholesterol homeostasis. Two of these, liver X receptor alpha (LXRalpha) (NR1H3) [1] and ubiquitous receptor (UR) (NR1H2) [1], appear to be involved in cholesterol reverse transport and disposal. LXRalpha null gene mice fail to adapt metabolically to high-cholesterol diets. We have recently shown that some 6alpha-hydroxylated bile acid analogs are selective activators of LXRalpha. In this report, we show that these orally administered LXRalpha agonists have an overall hypolipidemic effect in hypercholesterolemic rats, mice and hamsters, which indicates that in these animal models, endogenous LXRalpha agonist is a limiting factor for induction of cholesterol disposal. Furthermore, in animals, these 6alpha-hydroxylated bile acid analogs exhibit a unique pharmacokinetic profile and do not increase the serum triglyceride level; therefore, they may represent a novel class of therapeutic agents for cholesterol management.

Monoclonal antibodies against human telomerase reverse transcriptase (hTERT): preparation, characterization, and application

The catalytic subunit of human telomerase reverse transcriptase (hTERT), is the necessary and rate-limiting component to telomerase activation in cancer cells. To develop monoclonal antibodies (MAbs) against hTERT, a peptide-hTERT(9)-derived from specific motif T of hTERT was synthesized. Through fusion of splenocytes of BALB/c mice immunized with hTERT(9) with mouse myeloma cells, hybridomas were generated and clones secreting anti-hTERT(9) antibody were screened. After three rounds of limited dilution of candidate clones, three of which present stable and constant antibody production. The MAbs were hTERT(9)-specific and reactive with native hTERT of human cancer cells or tissues in Western blot and immunohistochemistry. The heavy chain variable regions from three hybridomas were cloned and sequenced confirming their mouse Ig derivation. The described investigation suggested that the generated MAbs to hTERT(9) could recognize native hTERT and be useful to cancer research.

[Combination chemotherapy with paclitaxel and carboplatin in the treatment of advanced non-small cell lung cancer]

BACKGROUND

To study the efficacy and toxicity of combined chemotherapy of paclitaxel and carboplatin in patients with advanced non-small cell lung cancer (NSCLC).

METHODS

Seventy-eight patients with advanced NSCLC received combined chemotherapy of paclitaxel 150 mg/m² and carboplatin 300 mg/m².

RESULTS

The response rate of native patients was 56.9% (33/58) and that of the repeated treatment group was 35% (7/20). The overall response rate was 51.3%(40/78). Four patients (5.1%) had complete response. The median duration of survival was 9 months, and 1-year survival rate was 33.3% (26/78). Toxicity was chiefly hematologic in the form of neutropenia. The major nonhematologic toxicity was arthromyalgia.

CONCLUSIONS

Combination chemotherapy of paclitaxel and carboplatin is well tolerated and effective in the treatment of advanced NSCLC.

[Pulmonary hyalinizing granuloma: a case report and a review of the literature]

OBJECTIVE

To highlight the characteristics of pulmonary hyalinizing granuloma (PHG).

METHOD

One patient with PHG confirmed by pathological assessment was presented and relevant literatures were reviewed.

RESULTS

PHG is a rare disease characterized by multiple bilateral pulmonary nodules. Symptoms include cough, dyspnea, chest pain, hemoptysis, fever and fatigue. Histologically, the nodules consist of haphazard or whorled arrays of lamellar, keloid - like collagen. Evidence suggests that the nodules are the result of a chronic exaggerated immune response.

CONCLUSIONS

PHG should be considered in patients showing multiple bilateral pulmonary nodules. The clinical course of PHG in most patients is benign. At present, there is no effective therapy.

Auto-oxidized cholesterol sulfates are antagonistic ligands of liver X receptors: implications for the development and treatment of atherosclerosis

Liver X receptors (LXRs) are members of the nuclear receptor superfamily that are involved in regulation of cholesterol transport and metabolism. Expression of cholesterol 7alpha-hydroxylase, cholesteryl ester transfer protein and certain ATP-binding cassette transporters that are responsible for cholesterol efflux from cells is regulated by LXR and its ligands. In this report we show that 5alpha, 6alpha-epoxycholesterol-3-sulfate (ECHS) and 7-ketocholesterol-3-sulfate inhibit transactivation of a reporter gene by LXR. Non-sulfated forms of these compounds, as well as many other steroid sulfates, had no antagonistic activity. Using chimeric receptors, the antagonistic activity of ECHS was dependent on its interaction with the ligand-binding domain of LXR. ECHS disrupts recruitment of the co-activator Grip 1 into a complex with agonist-bound LXR and this may be responsible for the observed antagonistic properties of these compounds. In various cultured cells, these LXR antagonists also promote de novo cholesterol synthesis and apoptosis. 7-Ketocholesterol and 5alpha, 6alpha-epoxycholesterol are present in blood and have been found in atherosclerotic plaques. If sulfated forms of these oxidized sterols are also present, they may have an important role in foam cell formation by inhibiting LXR function. Since LXR agonists can counteract the activity of these antagonists, they may have therapeutic potential against atherosclerosis.

Targeting of LAK activity to CEA-expressing tumor cells with an anti-CEA scFv/IL-2 fusion protein

BACKGROUND

Fusion of tumor-specific monoclonal antibody (MAb) and cytokines has proved to be an efficient way to target cytokines to tumor cells and hence focuses the killing activity of effector cells to the target cells. We previously produced a high affinity MAb, F11-39, against carcinoembryonic antigen (CEA), which is often overexpressed on the surface of various tumor cells.

MATERIALS AND METHODS

To target the cytotoxicity of effector cells to CEA-expressing tumor cells, we employed recombinant DNA techniques to fuse recombinant human interleukin-2 (rhIL-2) to a single chain variable fragment (scFv) antibody derived from F11-39. The resulting fusion protein, designated F39scFv/IL-2, was expressed in the Sp2/0-Ag14 mouse hybridoma cells, purified by CEA-affinity chromatography and characterized for the CEA-binding specificity and the IL-2 biological activity.

RESULTS

F39scFv/IL-2 protein effectively targeted rhIL-2 onto the surface of CEA-expressing tumor cells and consequently introduced a specific cytotoxicity of lymphokine-activated killer cells to the tumor cells.

CONCLUSIONS

This approach may be used for in vivo administration to localize IL-2 to tumor tissues, maximizing the immune response to CEA-expressing tumors while keeping systemic side effects to a minimum.

Suppression of experimental abdominal aortic aneurysms in the rat by treatment with angiotensin-converting enzyme inhibitors

PURPOSE

Pathologic remodeling of the extracellular matrix is a critical mechanism in the development and progression of abdominal aortic aneurysms (AAAs). Although angiotensin-converting enzyme (ACE) inhibitors are known to alter vascular wall remodeling in other conditions, their effects on AAAs are unknown. In this study we assessed the effect of ACE inhibitors in a rodent model of aneurysm development.

METHODS

Male Wistar rats underwent transient aortic perfusion with porcine pancreatic elastase, followed by treatment with one of three ACE inhibitors (captopril [CP], lisinopril [LP], or enalapril [EP]), an angiotensin (AT)1 receptor antagonist (losartan [LOS]), or water alone (9 rats in each group). Blood pressure and aortic diameter (AD) were measured before elastase perfusion and on day 14, with an AAA defined as an increase in AD (DeltaAD) of more than 100%. The structural features of the aortic wall were examined by means of light microscopy.

RESULTS

Aneurysmal dilatation consistently developed within 14 days of elastase perfusion in untreated rats, coinciding with the development of a transmural inflammatory response and destruction of the elastic media (mean DeltaAD, 223% +/- 28%). All three ACE inhibitors prevented AAA development (mean DeltaAD: CP, 67% +/- 4%; LP, 18% +/- 12%; and EP, 14% +/- 3%; each P <.05 vs controls). ACE inhibitors also attenuated the degradation of medial elastin without diminishing the inflammatory response. Surprisingly, the aneurysm-suppressing effects of ACE inhibitors were dissociated from their effects on systemic hemodynamics, and LOS had no significant effect on aneurysm development compared with untreated controls (mean DeltaAD, 186% +/- 19%).

CONCLUSION

Treatment with ACE inhibitors suppresses the development of elastase-induced AAAs in the rat. Although this is associated with the preservation of medial elastin, the mechanisms underlying these effects appear to be distinct from hemodynamic alterations alone or events mediated solely by AT1 receptors. Further studies are needed to elucidate how ACE inhibitors influence aortic wall matrix remodeling during aneurysmal degeneration.

Synthesis, biology, NMR and conformation studies of the topographically constrained delta-opioid selective peptide analogs of [beta-iPrPhe(3)]deltorphin I

Replacement of Phe3 in the endogenous delta-opioid selective peptide deltorphin I with four optically pure stereoisomers of the topographically constrained, highly hydrophobic novel amino acid beta-isopropylphenylalanine (beta-iPrPhe) produced four pharmacologically different deltorphin I peptidomimetics. Radiolabeled ligand-binding assays and in vitro biological evaluation indicate that the stereoconfiguration of the iPrPhe residue plays a crucial role in determining the binding affinity, bioactivity and selectivity of [beta-iPrPhe3]deltorphin I analogs: a (2S,3R) configuration of the iPrPhe3 residue in [beta-iPrPhe3]deltorphin I provided the most desirable biological properties with binding affinity (IC50 = 2 nM), bioassay potency (IC50 = 1.23 nM in MVD assay) and exceptional selectivity for the delta-opioid receptor over the mu-opioid receptor (30 000). Further conformational studies based on two-dimensional NMR and computer-assisted molecular modeling suggested a model for the possible bioactive conformation in which the Tyr1 and (2S,3R)-beta-iPrPhe3 residues adopt trans side-chain conformations, and the linear peptide backbone favors a distorted beta-turn conformation.

Growth suppression of hamster flank organs by topical application of catechins, alizarin, curcumin, and myristoleic acid

Hamster flank organ growth, as measured by an increase in the area of the pigmented macule, is androgen-dependent. When flank organs of a castrated hamster are treated topically with testosterone, the flank organ becomes larger and darker. Since this growth is known to be dependent on the intracellular active androgen, 5alpha-dihydrotestosterone (DHT), inhibitors of 5alpha-reductase which converts testosterone to DHT can inhibit the growth of the flank organ. Certain unsaturated aliphatic fatty acids, such as gamma-linolenic acid and myristoleic acid, as well as other natural compounds, including alizarin and curcumin, are 5alpha-reductase inhibitors and inhibited flank organ growth. Green tea catechins, including (-)-epicatechin-3-gallate, and (-)-epigallo-catechin-3-gallate (EGCG) are also 5alpha-reductase inhibitors and inhibited flank organ growth. However, (-)-epicatechin and (-)-epigallocatechin, which are not 5alpha-reductase inhibitors, also inhibited flank organ growth. EGCG also inhibited DHT-dependent growth of flank organs. These catechins, therefore, may act by a mechanism other than inhibition of 5alpha-reductase. The effect of EGCG and other compounds was localized at the site of application; they did not affect the growth of the contralateral flank organ in the same animal. Since these compounds do not appear to exhibit systemic effects, they may be potentially useful for treatment of androgen-dependent skin disorders.

A transcriptional activation function of p53 is dispensable for and inhibitory of its apoptotic function

The tumor suppressor p53 is an inducer of cell cycle arrest and programmed cell death (apoptosis). The ability of p53 to induce cell cycle arrest is linked to its ability to induce transcription of genes such as the cyclin-dependent kinase inhibitor p21. However, the dependence of p53-mediated apoptosis on transcriptional activation remains controversial. Ectopic expression of a temperature-sensitive (ts) p53 allele induced expression of p53 target genes and elicited both G1 and G2/M cell cycle arrest upon shift to the permissive temperature. Ectopic expression of the same ts p53 allele with two additional point mutations (Gln22, Ser23) that abolish p53-transcriptional activation did not induce p53 target genes and G1 nor G2/M cell cycle arrest. In HCT116 colon carcinoma cells ectopic expression of wild type p53 does not elicit apoptosis whereas p53 mutant deficient in trans-activation induces apoptosis. The ability of wild type p53 to induce apoptosis is restored in HCT116 cells that are null for p21. However, the trans-activation deficient mutant of p53 is still more potent mediator of apoptosis than wild type p53 in the p21 null cells. Although the ability of Gln22,Ser23 to trans-activate p53 target genes is diminished, it retains the ability to repress Bcl-2 expression. Thus, we conclude that while ectopic expression of wild type p53 can induce both G1 and G2/M arrest, in a p21 dependent manner, without apoptosis, a p53 mutant defective in trans-activation elicits apoptosis without inducing cell cycle arrest. Further, the anti-apoptotic function of p53 is dependent on trans-activation and is linked to cell cycle arrest. The results strongly suggest that the trans-activation deficient mutant is a more potent inducer of apoptosis because it lost its anti-apoptotic function and retains its ability to repress pro-apoptotic genes such as Bcl-2. Taken together, the results imply that employing a trans-activation deficient p53 in gene therapy approaches or the use of drugs that convert mutant p53 to a trans-activation-independent mediator of apoptosis may be much more efficient therapeutic approaches than current approaches that employ wild type p53.

[Genetic polymorphism of eight STR loci in the Han population in Henan province]

OBJECTIVE

To investigate the allele frequencies of eight short tandem repeats(STR) loci: TH01, FES, D19S400, D7S820, D16S539, D20S161, D3S1545 and D5S818 in Han population in Henan province.

METHODS

DNA was extracted with phenol-chloroform from EDTA-blood samples of the unrelated individuals in Henan province and amplified with PCR technique. The PCR product was analyzed with the undenatured PAGE vertical electrophoresis and silver-stain.

RESULTS

The authors got the frequencies of the eight loci. The heterozygosities of the eight loci are 0.66, 0.67, 0.80, 0.76, 0.79, 0.79, 0.78 and 0.78; the discrimination powers are 0.83, 0.83, 0.94, 0.91, 0.93, 0.93, 0.92 and 0.92.

CONCLUSION

The heterozygosities of the eight loci are high and the frequencies are in good agreement with Hardy-Weinberg equilibrium, so the eight loci can be used in individual identification testing.

Association of serum estrogen level and ischemic neuroprotection in female rats

Estrogen-related ischemic neuroprotection has been documented in male and ovariectomized female rats. The precise molecular mechanism underlying estrogen's neuroprotective effect remains obscure. In the present study, we examined whether endogenous estrogen levels affect post-ischemic outcomes in normal cycling female rats. Occlusion of both the common carotid arteries and the right middle cerebral artery (1.5 h) followed by reperfusion (24 h) caused cortical infarction, increased neutrophil accumulation, and elevated antioxidant enzyme and lactate dehydrogenase activities. These post-ischemic changes varied in the female rats and were inversely correlated with circulating estrogen levels. More severe post-ischemic changes and injury accompanied the decline in circulating estrogen levels in normal cycling female rats, indicating that estrogen is probably the major hormonal player in female resistance to ischemia.

[Preliminary study on pathogenicity of hepatitis G virus]

OBJECTIVE

To study the clinical, enzymatic and liver pathological changes in patients with hepatitis G virus (HGV) infection.

METHODS

RT- nested PCR was applied to detect HGV RNA in 368 patients with hepatic diseases. The liver biopsy tissue from one liver cirrhosis patient with simple HGV infection was examined.

RESULTS

Simple HGV RNA positive were found in 7 cases of 71 acute hepatitis jaundice, in 22 cases of 155 chronic hepatitis and in 3 cases of 51 liver cirrhosis. The immunohistochemistry of the liver biopsy tissue from a liver cirrhosis patient showed HGV NS5 antigen positive. However, HGV infection might occur simply or in combination with hepatitis B or C virus or super infected.

CONCLUSIONS

HGV RNA could be detected in acute hepatitis jaundice, chronic hepatitis, hepatitis B or C carriers, liver cirrhosis and hepatocellular carcinoma. HGV is proved to be a hepatotropic virus by pathological examination and immunohistochemistry, the virus located in the cytoplasm of the liver cells. It may cause chronic hepatitis and even liver cirrhosis, so HGV is pathogenic to liver tissue.

Cholestenoic acid is a naturally occurring ligand for liver X receptor alpha

Excessive cholesterol is eliminated from extrahepatic cells by reverse cholesterol transport, a process by which neutral sterols are transferred to extracellular acceptor lipoproteins for further transport to the liver. Another process independent of lipoproteins involves excretion of 3beta-hydroxy-5-cholesten-25(R)-26-carboxylic (cholestenoic) acid, a metabolite of 27-hydroxycholesterol. Physiological concentrations of cholestenoic acid activated the nuclear receptor liver X receptor alpha (LXR alpha; NR1H3), but not other oxysterol receptors. As a ligand, cholestenoic acid modulated interaction of LXR alpha with the nuclear receptor coactivator Grip-1. Cholestenoic acid, therefore, may function as a signaling molecule for regulation of lipid metabolism via LXR alpha.

Specific targeting strategies of cancer gene therapy using a single-chain variable fragment (scFv) with a high affinity for CEA

Two specific targeting strategies of cancer gene therapy using carcinoembryonic antigen (CEA) as a target are briefly reviewed here. One method is the specific targeting of suicide genes to CEA-expressing tumor cells by a retrovector displaying anti-CEA single-chain variable fragment (scFv). We reconstructed a recombinant retroviral vector that displays both anti-CEA scFv-expressing chimeric and normal envelope proteins and carries the inducible nitric oxide synthase (iNOS) gene. This recombinant retrovirus specifically bound, infected and killed only CEA-expressing tumor cells, indicating the cell specific retroviral vector delivery of the iNOS gene. Another novel method is the specific redirecting of cytotoxic T-cells to CEA-expressing tumor cells through chimeric receptors. We also reconstructed a chimeric receptor gene which encoded an anti-CEA scFv antibody and the zeta-chain of human TCR/CD3 complex and expressed it on T-cell surface. When incubated with CEA-expressing tumor cells in vitro, the transduced T-cells tended to make a rosette-like formation around the tumor cells, suggesting the cell specific targeting of T-cells.

The function of Xenopus Bloom's syndrome protein homolog (xBLM) in DNA replication

The Bloom's syndrome gene (BLM) plays a pivotal role in the maintenance of genomic stability in somatic cells. It encodes a DNA helicase (BLM) of the RecQ family, but the exact function of BLM remains elusive. To study this question, we have cloned the BLM homolog of the frog Xenopus laevis (xBLM) and have raised antibodies to it. Immunodepletion of xBLM from a Xenopus egg extract severely inhibits the replication of DNA in reconstituted nuclei. Moreover, the inhibition can be rescued by the addition of the recombinant xBLM protein. These results provide the first direct evidence that BLM plays an important role in DNA replication, suggesting that Bloom's syndrome may be the consequence of defective DNA replication.