Investigation of sliced body volume (SBV) as respiratory surrogate

The purpose of this study was to evaluate the sliced body volume (SBV) as a respiratory surrogate by comparing with the real‐time position management (RPM) in phantom and patient cases. Using the SBV surrogate, breathing signals were extracted from unsorted 4D CT images of a motion phantom and 31 cancer patients (17 lung cancers, 14 abdominal cancers) and were compared to those clinically acquired using the RPM system. Correlation coefficient (R), phase difference (D), and absolute phase difference (DA) between the SBV‐derived breathing signal and the RPM signal were calculated. 4D CT reconstructed based on the SBV surrogate (4D CTSBV) were compared to those clinically generated based on RPM (4D CTRPM). Image quality of the 4D CT were scored (SSBV and SRPM, respectively) from 1 to 5 (1 is the best) by experienced evaluators. The comparisons were performed for all patients, and for the lung cancer patients and the abdominal cancer patients separately. RPM box position (P), breathing period (T), amplitude (A), period variability (VT), amplitude variability (VA), and space‐dependent phase shift (F) were determined and correlated to SSBV. The phantom study showed excellent match between the SBV‐derived breathing signal and the RPM signal (R=0.99, D=−3.0%, DA=4.5%). In the patient study, the mean (± standard deviation (SD)) R, D, DA, T, VT, A, VA, and F were 0.92(±0.05), −3.3% (±7.5%), 11.4% (±4.6%), 3.6 (±  0.8) s, 0.19 (±  0.10), 6.6 (±  2.8) mm, 0.20 (±  0.08), and 0.40 (±  0.18) s, respectively. Significant differences in R and DA (p=0.04 and 0.001, respectively) were found between the lung cancer patients and the abdominal cancer patients. 4D CTRPM slightly outperformed 4D CTSBV: the mean (±  SD) SRPM and SSBV were 2.6 (±  0.6) and 2.9 (±  0.8), respectively, for all patients, 2.5 (±  0.6) and 3.1 (±  0.8), respectively, for the lung cancer patients, and 2.6 (±  0.7) and 2.8 (±  0.9), respectively, for the abdominal cancer patients. The difference between SRPM and SSBV was insignificant for the abdominal patients (p=0.59). F correlated moderately with SSBV (r=0.72). The correlation between SBV‐derived breathing signal and RPM signal varied between patients and was significantly better in the abdomen than in the thorax. Space‐dependent phase shift is a limiting factor of the accuracy of the SBV surrogate.

PACS number: 87.59.bd

Therapeutic and preventive effects of an epidermal growth factor receptor inhibitor on oral squamous cell carcinoma

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is the sixth most common human neoplasm worldwide. Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that is highly expressed in human OSCC and is a target for cancer therapy and prevention. This study investigated the therapeutic and preventive effects of an inhibitor of EGFR (PD153035) on OSCC.

METHODS

The effects of PD153035 were examined in human cancer cell lines in vitro, in an athymic nude mouse xenograft model in vivo, and in the 7,12-dimethyl benz[a]anthracene (DMBA)-induced hamster cheek pouch tumour model in vivo.

RESULTS

PD153035 significantly inhibited cell growth, delayed cell cycle progression and induced apoptosis in human OSCC cells in vitro. In vivo, PD153035 inhibited xenograft tumour growth in nude mice in a dose-dependent manner and prevented the development of OSCC at the postinitiation stage in the DMBA-induced hamster cheek pouch tumour model. PD153035 inhibited the DMBA-induced increases in cell proliferation and in levels of phosphorylated EGFR and phosphorylated signal transducer and activator of transcription 3 (STAT3) protein in the hamster cheek pouch.

CONCLUSIONS

Inhibitors of EGFR, such as PD153035, have potential value in the treatment and prevention of OSCC.

Transcriptional data: a new gateway to drug repositioning?

Recent advances in computational biology suggest that any perturbation to the transcriptional programme of the cell can be summarised by a proper ‘signature’: a set of genes combined with a pattern of expression. Therefore, it should be possible to generate proxies of clinicopathological phenotypes and drug effects through signatures acquired via DNA microarray technology.

Gene expression signatures have recently been assembled and compared through genome-wide metrics, unveiling unexpected drug–disease and drug–drug ‘connections’ by matching corresponding signatures. Consequently, novel applications for existing drugs have been predicted and experimentally validated.

Here, we describe related methods, case studies and resources while discussing challenges and benefits of exploiting existing repositories of microarray data that could serve as a search space for systematic drug repositioning.

Dosimetric comparison of treatment plans based on free breathing, maximum, and average intensity projection CTs for lung cancer SBRT

PURPOSE

To determine whether there is a CT dataset may be more favorable for planning and dose calculation by comparing dosimetric characteristics between treatment plans calculated using free breathing (FB), maximum and average intensity projection (MIP and AIP, respectively) CTs for lung cancer patients receiving stereotactic body radiation therapy (SBRT).

METHODS

Twenty lung cancer SBRT patients, treated on a linac with 2.5 mm width multileaf-collimator (MLC), were analyzed retrospectively. Both FB helical and four-dimensional CT scans were acquired for each patient. Internal target volume (ITV) was delineated based on MIP CTs and modified based on both ten-phase datasets and FB CTs. Planning target volume (PTV) was then determined by adding additional setup margin to ITV. The PTVs and beams in the optimized treatment plan based on FB CTs were copied to MIP and AIP CTs, with the same isocenters, MLC patterns and monitor units. Mean effective depth (MED) of beams, and some dosimetric parameters for both PTVs and most important organ at risk (OAR), lung minus PTV, were compared between any two datasets using two-tail paired t test.

RESULTS

The MEDs in FB and AIP plans were similar but significantly smaller (Ps < 0.001) than that in MIP plans. Minimum dose, mean dose, dose covering at least 90% and 95% of PTVs in MIP plans were slightly higher than two other plans (Ps < 0.008). The absolute volume of lung minus PTV receiving greater than 5, 10, and 20 Gy in MIP plans were significantly smaller than those in both FB and AIP plans (Ps < 0.008). Conformity index for FB plans showed a small but statistically significantly higher.

CONCLUSIONS

Dosimetric characteristics of AIP plans are similar to those of FB plans. Slightly better target volume coverage and significantly lower low-dose region (≤30 Gy) in lung was observed in MIP plans. The decrease in low-dose region in lung was mainly caused by the change of lung volume contoured on two datasets rather than the differences of dose distribution between AIP and MIP plans. Compare with AIP datasets, FB datasets were more prone to significant image artifacts and MIP datasets may overestimate or underestimate the target volume when the target is closer to the denser tissue, so AIP seems favorable for planning and dose calculation for lung SBRT.

MTHFR C677T polymorphism contributes to colorectal cancer susceptibility: evidence from 61 case-control studies

Methylenetetrahydrofolate reductase (MTHFR) is believed to be involved in folate metabolism which plays a critical role in carcinogenesis. To date, many case-control studies have investigated the association between MTHFR C677T polymorphism and colorectal cancer risk. However, the results were inconsistent. In order to derive a more precise estimation of the association, we conducted this meta-analysis. This meta-analysis recruited 61 published studies which were selected by a search of PubMed up to 31st September 2011, including 16,111 colorectal cancer cases and 23,192 controls. We used crude odds ratios (ORs) with 95 % confidence intervals (CIs) to assess the association between MTHFR C677T polymorphism and colorectal cancer susceptibility. Our results showed that MTHFR C667T polymorphism contributed to the decreased colorectal cancer risk in overall population (for TT vs. CC: OR = 0.89, 95 % CI = 0.82-0.97; for TT vs. CT/CC: OR = 0.88, 95 % CI = 0.83-0.92). In subgroup analysis by ethnicity, the results also indicated a correlation between the T allele of MTHFR C667T and the colorectal cancer risk in Asian population (for TT vs. CC: OR = 0.82, 95 % CI = 0.69-0.97; for TT vs. CT/CC: OR = 0.81, 95 % CI = 0.74-0.90). Additionally, the correlation was also observed in male subgroup in sub-analysis by gender (for TT vs. CC: OR = 0.82, 95 % CI = 0.71-0.93; for TT vs. CT/CC: OR = 0.81, 95 % CI = 0.71-0.92). In summary, our meta-analysis strongly indicated the MTHFR C667T polymorphism was associated with a reduced risk of CRC.

Quantification and minimization of uncertainties of internal target volume for stereotactic body radiation therapy of lung cancer

PURPOSE

To quantify uncertainties in delineating an internal target volume (ITV) and to understand how these uncertainties may be individually minimized for stereotactic body radiation therapy (SBRT) of early stage non-small cell lung cancer (NSCLC).

METHODS AND MATERIALS

Twenty patients with NSCLC who were undergoing SBRT were imaged with free-breathing 3-dimensional computed tomography (3DCT) and 10-phase 4-dimensional CT (4DCT) for delineating gross tumor volume (GTV)(3D) and ITV(10Phase) (ITV3). The maximum intensity projection (MIP) CT was also calculated from 10-phase 4DCT for contouring ITV(MIP) (ITV1). Then, ITV(COMB) (ITV2), ITV(10Phase+GTV3D) (ITV4), and ITV(10Phase+ITVCOMB) (ITV5) were generated by combining ITV(MIP) and GTV(3D), ITV(10phase) and GTV(3D), and ITV(10phase) and ITV(COMB), respectively. All 6 volumes (GTV(3D) and ITV1 to ITV5) were delineated in the same lung window by the same radiation oncologist. The percentage of volume difference (PVD) between any 2 different volumes was determined and was correlated to effective tumor diameter (ETD), tumor motion ranges, R(3D), and the amplitude variability of the recorded breathing signal (v) to assess their volume variations.

RESULTS

The mean (range) tumor motion (R(SI), R(AP), R(ML), and R(3D)) and breathing variability (v) were 7.6 mm (2-18 mm), 4.0 mm (2-8 mm), 3.3 mm (0-7.5 mm), 9.9 mm (4.1-18.7 mm), and 0.17 (0.07-0.37), respectively. The trend of volume variation was GTV(3D) <ITV1 <ITV2 ≈ ITV3 < ITV4 < ITV5. The means ± SDs of these volumes were 11.1 ± 9.3 cc, 13.2 ± 10.5 cc, 14.9 ± 11.0 cc, 14.7 ± 11.4 cc, 15.9 ± 11.7 cc, and 16.4 ± 11.8 cc, respectively. All comparisons between the target volumes showed statistical significance (P≤.001), except for ITV2 and ITV3 (P=.594). The PVDs for all volume pairs correlated negatively with ETD (r≤-0.658, P≤.006) and positively with R(3D) (r≥0.503, P≤.047). The PVDs for pairs of ITV2 vs ITV5 and ITV5 vs ITV4 negatively correlated with ETD (r=0.502, -0.626; P=.047, .010). No other correlation was found.

CONCLUSION

Uncertainties in individualized ITVs for SBRT of early stage NSCLC could effectively be minimized by combining information from 3DCT, 4DCT, and MIP. If these images cannot be efficiently contoured, a combination of ITV(MIP) and GTV(3D) could be an effective alternative.

How applicable are clinical practice guidelines to elderly patients with comorbidities?

OBJECTIVE

To examine the applicability of 10 common clinical practice guidelines (CPGs) to elderly patients with multiple comorbidities.

DESIGN

Content analysis of published Canadian CPGs for the following chronic diseases: diabetes, dyslipidemia, dementia, congestive heart failure, depression, osteoporosis, hypertension, gastroesophageal reflux disease, chronic obstructive pulmonary disease, and osteoarthritis.

MAIN OUTCOME MEASURES

Presence or absence of 4 key indicators of applicability of CPGs to elderly patients with multiple comorbidities. These indicators include any mention of older adults or people with comorbidities, time needed to treat to benefit in the context of life expectancy, and barriers to implementation of the CPG.

RESULTS

Out of the 10 CPGs reviewed, 7 mentioned treatment of the elderly, 8 mentioned people with comorbidities, 4 indicated the time needed to treat to benefit in the context of life expectancy, 5 discussed barriers to implementation, and 7 discussed the quality of evidence.

CONCLUSION

This study shows that although most CPGs discuss the elderly population, only a handful of them adequately address issues related to elderly patients with comorbidities. In order to make CPGs more patient centred rather than disease driven, guideline developers should include information on elderly patients with comorbidities.

Relative kinetics of anaerobic digestion under thermophilic and mesophilic conditions

With several advantages over the conventional mesophilic anaerobic digestion, such as better sludge quality and higher biogas production, thermophilic anaerobic digestion is regarded as a promising alternative for sludge digestion. Primary and activated sludges are complex materials, and historically, analysis of kinetics has been largely on whole sludge, without analysis of individual components. This paper analyses relative digestion kinetics of pure substrates designed to target main stages of sludge digestion under thermophilic and mesophilic conditions. Hydrolysis rate of cellulose was significantly influenced by temperature with hydrolysis coefficients of--at 55 degrees C (0.7 +/- 0.1 day(-1)), 60 degrees C (0.8 +/- 0.2 day(-1)), 65 degrees C (1.1 +/- 0.2 day(-1)) and 70 degrees C (1.2 +/- 0.2 day(-1)) over 38 degrees C (0.4 +/- 0.1 day(-1)). This strongly follows the Arrhenius relationship, with an activation energy (E(A)) of 31 +/- 4 kJ mol(-1), corresponding to an increase of 1.5x for each 10 degrees C of temperature increase. Glucose uptake was rapid with a wide variety of fermentation products detected under mesophilic conditions, while uptake was slower under thermophilic conditions with acetate and propionate being dominant products. Propionate acetogenesis and acetate-utilizing methanogenesis kinetics were not influenced by temperatures. Hydrolysis is widely regarded as a rate-limiting step in sludge digestion, thus improvements in hydrolysis rates as measured during this study have the potential for significant improvements in overall apparent sludge digestion rates.

Assessing the role of biochemical methane potential tests in determining anaerobic degradability rate and extent

The biodegradability and bioavailability of hydrolysis-limited substrates under anaerobic (and aerobic) conditions can be represented by two key parameters--degradability (f(d)), or the percentage that can be effectively be destroyed during digestion, and first order hydrolysis coefficient (k(hyd)), or the speed at which material breaks down. Biochemical methane potential (BMP) testing uses a batch test (in triplicate), and by fitting against a first order model, can fit both parameters in the same test. BMP testing is now being widely used for anaerobic process feasibility and design purposes, and standardisation efforts are ongoing. In this paper, we address a number of key issues relating to the test method and its analysis. This includes proposal of a new fitting and parameter estimation method, evaluation of the impact of inoculum to substrate ratio on fitted parameters, and comparison to performance in continuous systems. The new parameter estimation technique provides an estimate of parameter uncertainty and correlation, and is clearly more suitable than model transformation and linear regression. An inoculum volume ratio of at least 50% (2:1 on VS basis) was required on a cellulose substrate to use methane production as primary indicator, as found by comparing methane production and solubilisation of cellulose. Finally, on a typical material, waste activated sludge, the batch test was slightly conservative in terms of degradability and rate, indicating a bias in the BMP test. The test is a cost-effective and capable method to evaluate potential substrates, but it should be noted that it is generally conservative, especially if sub-optimal inoculum is used.

Therapeutic effect of statin on aortic stenosis: a review with meta-analysis

BACKGROUND

Aortic stenosis (AS) is a common progressive disease. Statins have been hypothesized to delay its progression via pleiotropic mechanisms. However, results of clinical trials focusing on statin therapy in AS patients have been controversial.

OBJECTIVE

To analyse and summarize the findings in recent statin trials and to discuss the rationale of statin usage in AS populations.

METHODS

A comprehensive database search was conducted by two independent reviewers. Controlled trials that compared progression of AS between statin and non-statin therapy published before 31 December 2008 were included. Data were extracted for meta-analysis, to estimate overall effects, if available. Factors that contributed to heterogeneities among the trials were analysed.

RESULTS

The meta-analysis included nine trials with a total of 2947 patients. Statin therapy displayed an overall statistically significant effect on delaying AS progression. The weighted mean difference (statin vs. control) of annual increase of peak aortic-jet velocity was -0·12 m/s (95% confidence interval -0·22 to -0·03); the increase of mean transaortic pressure gradient was -1·64 mmHg per year (-3·27 to -0·01); Heterogeneity-analysis suggested that the baseline risk factors and characteristics of the patients, the use of different statins, and the time point to initiate statin therapy, may be important considerations when interpreting the result of individual studies.

CONCLUSION

Although the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) trial reported negative results in delaying AS progression in low-risk patients, the potential benefits of statins in those with multiple risk factors and their value in preventing future coronary events call for further investigation of different categories of AS patients.

Early response to sibutramine in patients not meeting current label criteria: preliminary analysis of SCOUT lead-in period

The Sibutramine Cardiovascular Outcomes (SCOUT) trial protocol defines a patient population predominantly outside current European Union label criteria. This article explores responses to sibutramine during the 6-week, single-blind, lead-in period between patients who conformed to the label requirements ("conformers") and those who did not ("nonconformers"). SCOUT is an ongoing, randomized, double-blind, placebo-controlled outcome trial in overweight/obese patients at high risk of a cardiovascular event. In total, 10,742 patients received sibutramine and weight management during the lead-in period. Initial responses were assessed post hoc in label conformers and nonconformers. Of that 8.1% patients met label criteria; 91.9%, the majority with cardiovascular disease and/or blood pressure >145/90 mm Hg, were nonconformers. Conformers and nonconformers had similar reductions in body weight (median change -2.2 kg) and waist circumference (women: -2.0 cm for both groups; men: -1.5 cm vs. -2.0 cm for conformers and nonconformers, respectively) over the 6-week period. Greater blood pressure falls were evident in nonconformers (median change -3.5/-1.0 vs. -1.0/0.0 mm Hg). Both groups had small pulse rate increases; median 1.5 bpm (nonconformers) vs. 3.0 bpm (conformers). There was a low incidence of serious adverse events (conformers: 1.0%; nonconformers: 2.8%) and ~93% of patients in both groups completed the 6-week period. The SCOUT lead-in period evaluating weight management with sibutramine confirms its good tolerability and efficacy in patients who meet current label criteria. Preliminary data from high-risk patients for whom sibutramine is currently contraindicated suggest a low discontinuation rate and few serious adverse events but confirmation from the SCOUT outcome data is needed.

Finishing genomes with limited resources: lessons from an ensemble of microbial genomes

While new sequencing technologies have ushered in an era where microbial genomes can be easily sequenced, the goal of routinely producing high-quality draft and finished genomes in a cost-effective fashion has still remained elusive. Due to shorter read lengths and limitations in library construction protocols, shotgun sequencing and assembly based on these technologies often results in fragmented assemblies. Correspondingly, while draft assemblies can be obtained in days, finishing can take many months and hence the time and effort can only be justified for high-priority genomes and in large sequencing centers. In this work, we revisit this issue in light of our own experience in producing finished and nearly-finished genomes for a range of microbial species in a small-lab setting. These genomes were finished with surprisingly little investments in terms of time, computational effort and lab work, suggesting that the increased access to sequencing might also eventually lead to a greater proportion of finished genomes from small labs and genomics cores.

Weight and blood pressure response to weight management and sibutramine in diabetic and non-diabetic high-risk patients: an analysis from the 6-week lead-in period of the sibutramine cardiovascular outcomes (SCOUT) trial

OBJECTIVE

To assess treatment responses to sibutramine and weight management in diabetic patients during the lead-in period of the Sibutramine Cardiovascular OUTcomes (SCOUT) trial.

METHODS

SCOUT is an ongoing, prospective, randomized, double-blind, placebo-controlled outcome trial in cardiovascular high-risk overweight/obese patients. A total of 10 742 patients received single-blind sibutramine and individualized weight management during the 6-week lead-in period; 84% had a history of type 2 diabetes mellitus and additional co-morbidities. Post-hoc analyses assessed anthropomorphic and vital sign responses between patients with and without diabetes.

RESULTS

Concomitant antidiabetic medication use was reported by 86% of the diabetic patients (approximately 30% required insulin-alone or in combination). Body weight and waist circumference decreased in diabetic patients: median 2.1 kg; 2.0 cm (both men and women); for those on insulin: 1.9 kg; 1.5/2.0 cm (men/women); without insulin: 2.3 kg; 2.0 cm (both men and women); blood pressure (BP) was also reduced (median systolic/diastolic 3.5/1.0 mmHg) with larger reductions in diabetic patients who were hypertensive and/or lost the most weight (>5%). In diabetic patients who entered with BP at target (<130/<85 mmHg) but did not lose weight (N = 245), increases of 3.5/2.0 mmHg were observed. Non-diabetic patients had greater weight losses (2.5 kg) but smaller reductions in BP (systolic/diastolic -2.5/-0.5 mmHg). Pulse rate increases were less in diabetic vs. non-diabetic patients (1.5 vs. 2.0 bpm).

CONCLUSION

In these high-risk diabetic patients, sibutramine and lifestyle modifications for 6 weeks resulted in small, but clinically relevant, median reductions in body weight, waist circumference and BP. A small median increase in pulse rate was recorded.

TOB suppresses breast cancer tumorigenesis

Transducer of ErbB-2 (TOB) is a member of the TOB/Btg gene family. A role for TOB in the suppression of human tumorigenesis has been proposed, based on the observations that TOB-knockout mice spontaneously form tumors and TOB expression is lost in human lung and thyroid cancers. However, the role of TOB in human breast cancer remains unknown. To evaluate the this role, we screened a panel of breast cancer cell lines for TOB expression levels and found that they are inversely correlated with the tumorigenicity and metastatic potential of the cell lines. In addition, we demonstrated for the first time that TOB expression is inversely correlated with breast cancer progression in clinical specimens. These results strongly indicate that the loss of TOB expression plays a role in breast cancer progression. We have also provided the first evidence that TOB functions as a tumor suppressor in breast cancer MCF-7 cells, using gain-of-function and loss-of-function approaches to manipulate TOB expression. Cell-cycle analysis further revealed that TOB can prolong the G1-S phase transition by inducing arrest at G1-S phase. Moreover, upregulation of the cyclin-dependent kinase inhibitor p27 and downregulation of the antiapoptotic proteins Bcl-2 and Bcl-XL were observed in MCF7/TOB transfectants. Conversely, opposite results were observed in shRNA-TOB transfectants. Furthermore, decreased activity of Erk2, AKT, CrkL, PDK1, and Smads were observed in TOB-overexpressing cells. Taken together, these data provide evidence that TOB can function as a tumor suppressor in breast cancer through modulation and regulation of multiple signaling pathways.

[Butyl-p-hydroxybenzoate stimulates cystic fibrosis transmembrane conductance regulator Cl- transport]

This study is to investigate the activation effect of butyl-p-hydroxybenzoate (Bpb) on cAMP-dependent cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel gating. A stably transfected Fischer rat thyroid (FRT) epithelial cell lines co-expressing human CFTR and a green fluorescent protein mutant with ultra-high halide sensitivity (EYFP) were used to measure CFTR-mediated iodide influx rates. Bpb was identified as an effective activator of wild-type CFTR chloride channel, it can correct delta F508-CFTR gating defects but not processing defect. Bpb can't potentiate G551D-CFTR channel gating. The activity was reversible and dose-dependent. The study also provided clues that Bpb activates CFTR chloride channel through a direct binding mechanism. Our study identified Bpb as a novel structure CFTR activator. Bpb may be useful for probing CFTR channel gating mechanisms and as a lead compound to develop pharmacological therapy for CFTR-related disease.

PTEN polymorphisms and the risk of esophageal carcinoma and gastric cardiac carcinoma in a high incidence region of China

PTEN, as a tumor suppressor gene, plays an important role in regulating cell growth, proliferation, and apoptosis. Two common polymorphisms, -9C/G and IVS4 (-/+), may alter susceptibility to the disease. To test the hypothesis that the genetic variations of PTEN play a role in the etiology of esophageal squamous cell carcinoma (ESCC) and gastric cardiac adenocarcinoma (GCA), a population-based case-control study was conducted in 350 ESCC patients, 257 GCA patients, and 634 healthy controls from a high-incidence region of Hebei province, China. The PTEN polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP). The results showed that the family history of upper gastrointestinal cancer (UGIC) significantly increased the risk of developing ESCC and GCA (the age, gender and smoking status adjusted OR = 1.73 and 1.67; 95% CI = 1.29-2.32 and 1.28-2.19, respectively). The overall distribution of the PTEN -9C/G genotype was not significantly different between cancer patients and controls. Compared with the PTEN IVS4-/- genotype, the IVS4+/+ genotype significantly decreased the risk of ESCC and GCA development, the adjusted OR was 0.64 (95% CI = 0.44-0.94) and 0.63 (95% CI = 0.41-0.98), respectively. Stratification analysis by gender, age, smoking status and family history of UGIC showed that the PTEN IVS4-/+ genotype only reduced the risk of ESCC (adjusted OR = 0.55, 95%CI = 0.34-0.90) among subjects with family history of UGIC. While the IVS4+/+ genotype decreased the susceptibility to both ESCC and GCA (adjusted OR = 0.61 and 0.57, 95% CI = 0.37-0.98 and 0.34-0.98, respectively) among male subjects, the IVS4+/+ genotype only decreased the risk of ESCC development among subjects younger than 55 years (adjusted OR = 0.43, 95% CI = 0.21-0.85). In addition, the haplotype analysis found that the -9C/IVS4- haplotype increased the risk of developing ESCC and GCA (OR = 1.31 and 1.24, 95% CI = 1.08-1.58 and 1.001-1.53). Our results suggested that the PTEN IVS4+/+ homozygote may play a protective role in the development of ESCC and GCA, while the haplotype -9C/IVS4- might be the risk factor of the development of ESCC and GCA in the high incidence region population of Hebei province, China.

Association of CDH1 single nucleotide polymorphisms with susceptibility to esophageal squamous cell carcinomas and gastric cardia carcinomas

E-cadherin (CDH1) is a tumor suppressor involved in epithelial cell-cell interactions. Single nucleotide polymorphisms (SNP) in the CDH1 gene, -160C/A and -347G/GA in the 5'-promoter region and +54C/T in the 3'-untranslated region (UTR) have been shown to be associated with tumor development and progression via modifying transcriptional activity, mRNA stability or protein expression. To investigate the influence of CDH1 SNP on susceptibility to esophageal squamous cell carcinomas (ESCC) and gastric cardia adenocarcinomas (GCA), a case-control study was conducted among 333 ESCC patients, 239 GCA patients and 343 controls from a northern Chinese population. CDH1 polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis. The results showed that; (i) genotypes with the +54C allele (C/C or C/T) significantly increased the risk of developing both ESCC and GCA compared to the +54T/T genotype (age and gender adjusted odds ratio [OR] = 1.45 and 2.28, 95% confidence interval [CI] = 1.06-1.99 and 1.58-3.30, respectively), and this association was significant only among non-smokers (OR = 1.68 and 2.64, 95% CI = 1.01-2.80 and 1.43-4.87 for ESCC and GCA, respectively), and individuals without a family history of upper gastrointestinal cancer (OR = 2.63 and 2.97, 95% CI = 1.36-5.10 and 95% CI = 1.32-6.68 for ESCC and GCA, respectively); (ii) compared with the -347G/G genotype, the -347GA and GA/GA genotypes significantly increased the risk of developing GCA (OR = 1.45, 95 % CI = 1.03-2.04); (iii) there was a significant association of CDH1-160C/-347G/+54C and -160C/-347GA/+54C haplotypes with the development of GCA, compared with the -160C/-347G/+54T haplotype (OR = 1.80 and 2.21, 95% CI = 1.33-2.44 and 1.43-3.42, respectively); and (iv) the influence of CDH1 SNP on the depth of tumor invasion and lymphatic metastasis in ESCC and GCA patients was not observed in this study. The present study indicates that CDH1 polymorphisms might modify susceptibility to ESCC and/or GCA.

Adhesion of endothelial cells using self-assembly peptides under precise deformation control of tissue-engineered vessels

The objective of this study was to anchor endothelial cells using self-assembly peptides under precise deformation control of tissue-engineered vessels. An acelluarized vascular matrix was used as the control group to examine the function of self-assembly peptides. In the experiment group, the self-assembly peptides were added to the inner surface of tissue-engineered vessels to form a monolayer. Then the endothelial cells were injected into the vascular lumen. A deformation control system was developed which was based on real-time image analysis and feedback control system. After dynamic culture by different deformation (set points 1, 5, and 10 per cent), the endothelial cell densities of experimental and control groups were compared. Both the self-assembly peptides and the extent of deformation affected the endothelial cell density on the inner surface of tissue-engineered vessels. The construct with self-assembly peptides under 5 per cent deformation gained the highest endothelial cell density. It was concluded that the deformation of assembled peptides contributes to the development and adhesion of endothelial cells in the inner surface of tissue-engineered vessels.

The p73 polymorphisms are not associated with susceptibility to esophageal squamous cell carcinoma in a high incidence region of China

P73, a p53 homolog, has some p53-like activities and plays an important role in modulating cell cycle, apoptosis and DNA repair. The two linked polymorphisms in the non-coding region of exon2 of p73 gene, named G4C14-A4T14, may alter translation efficiency of the gene. The transcription of p73 gene is initiated by three promoters, termed P1-P3. There is a single nucleotide substitution (-386G/A) in the P3 promoter region with unknown function. To test the hypothesis that the genetic variations in the exon2 and P3 promoter play a role in the etiology of esophageal squamous cell carcinoma (ESCC), we conducted a population-based case-control study in 348 ESCC patients and 583 healthy controls from a high incidence region of Hebei province, China. The p73 polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP). The results showed that the family history of upper gastrointestinal cancer (UGIC) significantly increased the risk of developing ESCC (the age, sex and smoking status adjusted OR = 2.02, 95% CI = 1.54-2.67). The overall distribution of the p73 genotype, allelotype and haplotype in cancer patients and controls were not significantly different (all P-values are above 0.05). Stratification analysis by smoking status and family history of UGIC also did not show the significant influence of the polymorphisms on the risk of ESCC development. The results suggested that the p73 exon2 G4C14-A4T14 and P3 promoter -386G/A polymorphisms might not be used as potential markers to predicate the risk of ESCC development in northern China.

Genotypic comparison of five isolates of Rickettsia prowazekii by multilocus sequence typing

Genetic traits of five Rickettsia prowazekii isolates, including the first from Africa and North America, and representatives from human and flying squirrels were compared using multilocus sequence typing. Four rickettsial genes encoding 17 kDa genus-common antigen (17 kDa gene), citrate synthase (gltA), OmpB immunodominant antigen (ompB) and 120 kDa cytoplasmic antigen (sca4) were examined. Sequence identities of 17 kDa gene and gltA were 100% among the isolates. Limited sequence diversity of ompB (0.02-0.11%) and sca4 (0.03-0.20%) was enough to distinguish the isolates, and evaluation of the combined four genes provided a method to easily differentiate R. prowazekii from other rickettsiae.

Mechanisms of TSC-mediated control of synapse assembly and axon guidance

Tuberous sclerosis complex is a dominant genetic disorder produced by mutations in either of two tumor suppressor genes, TSC1 and TSC2; it is characterized by hamartomatous tumors, and is associated with severe neurological and behavioral disturbances. Mutations in TSC1 or TSC2 deregulate a conserved growth control pathway that includes Ras homolog enriched in brain (Rheb) and Target of Rapamycin (TOR). To understand the function of this pathway in neural development, we have examined the contributions of multiple components of this pathway in both neuromuscular junction assembly and photoreceptor axon guidance in Drosophila. Expression of Rheb in the motoneuron, but not the muscle of the larval neuromuscular junction produced synaptic overgrowth and enhanced synaptic function, while reductions in Rheb function compromised synapse development. Synapse growth produced by Rheb is insensitive to rapamycin, an inhibitor of Tor complex 1, and requires wishful thinking, a bone morphogenetic protein receptor critical for functional synapse expansion. In the visual system, loss of Tsc1 in the developing retina disrupted axon guidance independently of cellular growth. Inhibiting Tor complex 1 with rapamycin or eliminating the Tor complex 1 effector, S6 kinase (S6k), did not rescue axon guidance abnormalities of Tsc1 mosaics, while reductions in Tor function suppressed those phenotypes. These findings show that Tsc-mediated control of axon guidance and synapse assembly occurs via growth-independent signaling mechanisms, and suggest that Tor complex 2, a regulator of actin organization, is critical in these aspects of neuronal development.

A model system for increasing the intensity of whole-cell biocatalysis: investigation of the rate of oxidation of D-sorbitol to L-sorbose by thin bi-layer latex coatings of non-growing Gluconobacter oxydans

We developed a novel <50-microm thick nano-porous bi-layer latex coating for preserving Gluconobacter oxydans, a strict aerobe, as a whole cell biocatalyst. G. oxydans was entrapped in an acrylate/vinyl acetate co-polymer matrix (T (g) approximately 10 degrees C) and cast into 12.7-mm diameter patch coatings (cellcoat) containing approximately 10(9) CFU covered by a nano-porous topcoat. The oxidation of D-sorbitol to L-sorbose was used to investigate the coating catalytic properties. Intrinsic kinetics was studied in microbioreactors using a pH 6.0 D-sorbitol, phosphate, pyruvate (SPP) non-growth medium at 30 degrees C, and the Michaelis-Menten constants determined. By using a diffusion cell, cellcoat and topcoat diffusivities, optimized by arresting polymer particle coalescence by glycerol and/or sucrose addition, were determined. Cryo-FESEM images revealed a two-layer structure with G. oxydans surrounded by <40-nm pores. Viable cell density, cell leakage, and oxidation kinetics in SPP medium for >150 h were investigated. Even though the coatings were optimized for permeability, approximately 50% of G. oxydans viability was lost during cellcoat drying and further reduction was observed as the topcoat was added. High reaction rates per unit volume of coating (80-100 g/L x h) were observed which agreed with predictions of a diffusion-reaction model using parameters estimated by independent experiments. Cellcoat effectiveness factors of 0.22-0.49 were observed which are 20-fold greater than any previously reported for this G. oxydans oxidation. These nano-structured coatings and the possibility of improving their ability to preserve G. oxydans viability may be useful for engineering highly reactive adhesive coatings for multi-phase micro-channel and membrane bioreactors to dramatically increase the intensity of whole-cell oxidations.

Decision support for tendon tissue engineering

The aim of this study is to provide decision support with artificial intelligence for tendon tissue engineering strategies. The experimental data of tissue-engineered tendons were integrated and standardized with a centralized database, and a decision support system was developed using both artificial neural networks and decision trees. The decision support system was trained with existing cases in the database, and then was used to generate tissue engineering schemes for new experimental animals. Following the schemes generated by the artificial intelligent system, we cured 28 of the 30 experimental animals. In conclusion, artificial intelligence is a powerful method for decision support in the tendon tissue engineering realm.

G(o) signaling is required for Drosophila associative learning

Heterotrimeric G(o) is one of the most abundant proteins in the brain, yet relatively little is known of its neural functions in vivo. Here we demonstrate that G(o) signaling is required for the formation of associative memory. In Drosophila melanogaster, pertussis toxin (PTX) is a selective inhibitor of G(o) signaling. The postdevelopmental expression of PTX within mushroom body neurons robustly and reversibly inhibits associative learning. The effect of G(o) inhibition is distributed in both gamma- and alpha/beta-lobe mushroom body neurons. However, the expression of PTX in neurons adjacent to the mushroom bodies does not affect memory. PTX expression also does not interact genetically with a rutabaga adenylyl cyclase loss-of-function mutation. Thus, G(o) defines a new signaling pathway required in mushroom body neurons for the formation of associative memory.

Cloning and sequence analysis of the 22-kDa antigen genes of Orientia tsutsugamushi strains Kato, TA763, AFSC 7, 18-032460, TH1814, and MAK 119

The 22-kDa protein antigen is one of several antigens recognized by sera from scrub typhus patients infected with Orientia tsutsugamushi. The 22-kDa protein genes from six O. tsutsugamushi strains (Kato, TA763, AFSC 7, 18-032460, TH1814, MAK119) were cloned and their sequences were determined and compared to each other and to the Karp strain sequence listed in GenBank. The sequence alignment revealed that the promoter regions of these seven strains were highly conserved. However, the ORFs exhibited some variation. The phylogenetic analysis of the DNA sequences indicated that among the seven strains assessed, Kato and TA763 were the most closely related, while Karp and TH1814 were the most distantly related. The information gained from this analysis will facilitate our selection of O. tsutsugamushi strains from which antigens should be derived to be included in a multivalent vaccine candidate for scrub typhus.

A Drosophila nonvisual arrestin is required for the maintenance of olfactory sensitivity

Nonvisual arrestins are a family of multifunctional adaptor molecules that regulate the activities of diverse families of receptors including G protein-coupled receptors, frizzled, and transforming growth factor-beta receptors. These activities indicate broad roles in both physiology and development for nonvisual arrestins. Drosophila melanogaster has a single nonvisual arrestin, kurtz, which is found at high levels within the adult olfactory receptor neurons (ORNs), suggesting a role for this gene in modulating olfactory sensitivity. Using heat-induced expression of a krz cDNA through development, we rescued krz(1) lethality. The resulting adults lacked detectable levels of krz in the olfactory system. The rescued krz(1) homozygotes have an incompletely penetrant antennal structural defect that was completely rescued by the neural expression of a krz cDNA. The krz(1) loss-of-function adults without visible antennal defects displayed diminished behavioral responsiveness to both aversive and attractive odors and also demonstrated reduced olfactory receptor potentials. Both the behavioral and electrophysiological phenotypes were rescued by the targeted expression of the krz cDNA within postdevelopmental ORNs. Thus, krz is required within the nervous system for antennal development and is required later in the ORNs for the maintenance of olfactory sensitivity in Drosophila. The reduced receptor potentials in krz(1) antenna indicate that nonvisual arrestins are required for the early odor-induced signaling events within the ORNs.

Consolidation of fear extinction requires protein synthesis in the medial prefrontal cortex

Extinction of conditioned fear is thought to form a long-term memory of safety, but the neural mechanisms are poorly understood. Consolidation of extinction learning in other paradigms requires protein synthesis, but the involvement of protein synthesis in extinction of conditioned fear remains unclear. Here, we show that rats infused intraventricularly with the protein synthesis inhibitor anisomycin extinguished normally within a session but were unable to recall extinction the following day. Anisomycin-treated rats showed no savings in the rate of re-learning of extinction, consistent with amnesia for extinction training. The identical effect was observed when anisomycin was microinfused into the medial prefrontal cortex (mPFC) but not the insular cortex. Furthermore, we observed that extinction training increased c-Fos levels in the mPFC but not in the insular cortex, consistent with extinction-induced gene expression in the mPFC. These findings extend previous lesion and unit-recording data by demonstrating that the mPFC is a critical storage site for extinction memory, rather than simply a pathway for expression of extinction. Understanding consolidation of fear extinction could lead to new treatments for anxiety disorders in which fear extinction is thought to be compromised.

Gender-specific proteomic alterations in glycolytic and mitochondrial pathways in aging monkey hearts

We utilized proteomic techniques in a primate model (Macaca fascicularis) of aging to determine potential mechanisms to explain gender differences in protection of the aging heart. The majority of prior work in this field utilized rodent models, and importantly no prior study utilized a proteomic approach in the aging heart. We studied changes in proteins in seven monkeys in each group (young and old males and females (YMs, OMs, YFs, and OFs, respectively)), and used two-dimensional gel electrophoresis in combination with mass spectrometry in five monkeys in each group. We found decreases (P < 0.05) in the expression of key enzymes in glycolysis (e.g. pyruvate kinase, alpha-enolase, triosephosphate isomerase), glucose oxidation (e.g. pyruvate dehydrogenase E1 beta-subunit), and the tricarboxylic acid (TCA) cycle (2-oxoglutarate dehydrogenase) in left ventricular (LV) samples from OM monkeys; these changes in glycolytic, glucose oxidation, and TCA enzymes were not observed either in YMs, YFs or OFs. We found additional gender differences in the reduced expression and function of proteins that are responsible for electron transport and oxidative phosphorylation in mitochondria only in hearts from OM monkeys, with corresponding decreased oxidation rates with NADH and ascorbate-N,N,N',N' ''-tetramethyl-p-phenylenediamine substrates. The changes in glycolytic and mitochondrial metabolic pathways in OM monkey hearts are similar to changes observed in hearts affected by diabetes or LV dysfunction, and could be involved in the mechanism for the cardiomyopathy of aging. The sparing of these changes in OF hearts could be involved in the mechanism mediating delayed cardiovascular risk in OFs.

Comparative genomics of Rickettsia prowazekii Madrid E and Breinl strains

Rickettsia prowazekii, the causative agent of epidemic typhus, has been responsible for millions of human deaths. Madrid E is an attenuated strain of R. prowazekii, while Breinl is a virulent strain. The genomic DNA sequence of Madrid E has recently been published. To study the genomic variations between Madrid E (reference) and Breinl (test) DNAs, cohybridization experiments were performed on a DNA microarray containing all 834 protein-coding genes of Madrid E. Of the 834 genes assessed, 24 genes showed 1.5- to 2.0-fold increases in hybridization signals in Breinl DNA compared to Madrid E DNA, indicating the presence of genomic variations in approximately 3% of the total genes. Eighteen of these 24 genes are predicted to be involved in different functions. Southern blot analysis of five genes, virB4, ftsK, rfbE, lpxA, and rpoH, suggested the presence of an additional paralog(s) in Breinl, which might be related to the observed increase in hybridization signals. Studies by real-time reverse transcription-PCR revealed an increase in expression of the above-mentioned five genes and five other genes. In addition to the elevated hybridization signals of 24 genes observed in the Breinl strain, one gene (rp084) showed only 1/10 the hybridization signal of Madrid E. Further analysis of this gene by PCR and sequencing revealed a large deletion flanking the whole rp084 gene and part of the rp083 gene in the virulent Breinl strain. The results of this first rickettsial DNA microarray may provide some important information for the elucidation of pathogenic mechanisms of R. prowazekii.

Hzf-3 expression in the amygdala after establishment of conditioned taste aversion

We studied the regulation of the expression of the inducible orphan nuclear receptor known as HZF-3 (or Nurr1) in acquisition of conditioned taste aversion in rats. Our results show that HZF-3 expression in the lateral/basolateral (LA/BLA) amygdala complex was significantly up-regulated when both the conditioned and the unconditioned stimuli were paired, but not when either of the stimuli was presented alone. Induction in the LA/BLA had a faster onset than induction in the central nucleus of the amygdala. The results implicate HZF-3 in the acquisition of associative aversive experiences.

Evidence of high incidence of EGFRvIII expression and coexpression with EGFR in human invasive breast cancer by laser capture microdissection and immunohistochemical analysis

EGFRvIII was first reported in human glioblastomas. Subsequent reports indicated EGFRvIII protein to be frequently detected in several other human cancers, but not in normal tissues. Our previous studies suggested that EGFRvIII could induce a transformation from ligand-dependent non-tumorigenic cell line to ligand-independent malignant phenotype cells in vitro and in vivo. Transfection of EGFRvIII in MCF-7 cell line resulted in a 3-fold increase in colony formation and significantly enhanced tumorigenicity in nude mice (p < 0.001). EGFRvIII could also induce ErbB-2 phosphorylation. The existence and significance of EGFRvIII transcript in human breast cancer, however, was not reported. In our study, we detected the presence of EGFRvIII mRNA and revealed a high incidence (67.8%) of EGFRvIII transcript in human primary invasive breast cancer by utilizing laser capture microdissection (LCM)/RT-PCR to capture pure breast cancer cells. In addition, 57.1% of the infiltrating breast carcinomas expressed both EGFRwt and EGFRvIII mRNA in the same tumor. There is no detectable EGFRvIII mRNA in normal breast tissue. Evaluation of the EGFRwt and EGFRvIII protein levels in the same sample sets by immunohistochemical analysis further confirmed the LCM/RT-PCR finding. Our study provides first direct evidence of high incidence of coexpression of EGFRvIII and EGFRwt in human invasive breast cancer tissue. The unique characteristics and high prevalence of EGFRvIII in invasive human breast cancer as well as negative expression in normal breast may suggest its important role in breast carcinogenesis and make it an ideally potential target for treatment of breast cancer without interrupting normal EGFR signaling.

The dynamics of bone marrow stromal cells in the proliferation of multipotent hematopoietic progenitors by substance P: an understanding of the effects of a neurotransmitter on the differentiating hematopoietic stem cell

Communication within the hematopoietic-neuroendocrine-immune axis is partly mediated by neurotransmitters (e.g. substance P, SP) and cytokines. SP mediates neuromodulation partly through the stimulation of bone marrow (BM) progenitors. This study shows that SP, through the neurokinin-1 receptor, stimulates the proliferation of primitive hematopoietic progenitors: cobblestone-forming cells (CAFC, CD34+). This effect is optimal when macrophage is included within the fibroblast support. Indirect induction of IL-1 could be important in the proliferation of CAFC colonies by SP. Phenotypic and functional studies suggest that SP might directly interact with the CD34+/CD45(dim) population. These studies indicate that SP can initiate a cascade of biological responses in the BM stroma and stem cells to stimulate hematopoiesis.

Correlation between transcriptome and interactome mapping data from Saccharomyces cerevisiae

Genomic and proteomic approaches can provide hypotheses concerning function for the large number of genes predicted from genome sequences. Because of the artificial nature of the assays, however, the information from these high-throughput approaches should be considered with caution. Although it is possible that more meaningful hypotheses could be formulated by integrating the data from various functional genomic and proteomic projects, it has yet to be seen to what extent the data can be correlated and how such integration can be achieved. We developed a 'transcriptome-interactome correlation mapping' strategy to compare the interactions between proteins encoded by genes that belong to common expression-profiling clusters with those between proteins encoded by genes that belong to different clusters. Using this strategy with currently available data sets for Saccharomyces cerevisiae, we provide the first global evidence that genes with similar expression profiles are more likely to encode interacting proteins. We show how this correlation between transcriptome and interactome data can be used to improve the quality of hypotheses based on the information from both approaches. The strategy described here may help to integrate other functional genomic and proteomic data, both in yeast and in higher organisms.

Identification of potential interaction networks using sequence-based searches for conserved protein-protein interactions or "interologs"

Protein interaction maps have provided insight into the relationships among the predicted proteins of model organisms for which a genome sequence is available. These maps have been useful in generating potential interaction networks, which have confirmed the existence of known complexes and pathways and have suggested the existence of new complexes and or crosstalk between previously unlinked pathways. However, the generation of such maps is costly and labor intensive. Here, we investigate the extent to which a protein interaction map generated in one species can be used to predict interactions in another species.

TFIIH inhibits CDK9 phosphorylation during human immunodeficiency virus type 1 transcription

Tat stimulates human immunodeficiency virus, type 1 (HIV-1), transcription elongation by recruitment of the human transcription elongation factor P-TEFb, consisting of CDK9 and cyclin T1, to the TAR RNA structure. It has been demonstrated further that CDK9 phosphorylation is required for high affinity binding of Tat/P-TEFb to the TAR RNA structure and that the state of P-TEFb phosphorylation may regulate Tat transactivation. We now demonstrate that CDK9 phosphorylation is uniquely regulated in the HIV-1 preinitiation and elongation complexes. The presence of TFIIH in the HIV-1 preinitiation complex inhibits CDK9 phosphorylation. As TFIIH is released from the elongation complex between +14 and +36, CDK9 phosphorylation is observed. In contrast to the activity in the "soluble" complex, phosphorylation of CDK9 is increased by the presence of Tat in the transcription complexes. Consistent with these observations, we have demonstrated that purified TFIIH directly inhibits CDK9 autophosphorylation. By using recombinant TFIIH subcomplexes, our results suggest that the XPB subunit of TFIIH is responsible for this inhibition of CDK9 phosphorylation. Interestingly, our results further suggest that the phosphorylated form of CDK9 is the active kinase for RNA polymerase II carboxyl-terminal domain phosphorylation.

Defective interplay of activators and repressors with TFIH in xeroderma pigmentosum

Inherited mutations of the TFIIH helicase subunits xeroderma pigmentosum (XP) B or XPD yield overlapping DNA repair and transcription syndromes. The high risk of cancer in these patients is not fully explained by the repair defect. The transcription defect is subtle and has proven more difficult to evaluate. Here, XPB and XPD mutations are shown to block transcription activation by the FUSE Binding Protein (FBP), a regulator of c-myc expression, and repression by the FBP Interacting Repressor (FIR). Through TFIIH, FBP facilitates transcription until promoter escape, whereas after initiation, FIR uses TFIIH to delay promoter escape. Mutations in TFIIH that impair regulation by FBP and FIR affect proper regulation of c-myc expression and have implications in the development of malignancy.

Active remodeling of somatic nuclei in egg cytoplasm by the nucleosomal ATPase ISWI

Cloning by the transplantation of somatic nuclei into unfertilized eggs requires a dramatic remodeling of chromosomal architecture. Many proteins are specifically lost from nuclei, and others are taken up from the egg cytoplasm. Recreating this exchange in vitro, we identified the chromatin-remodeling nucleosomal adenosine triphosphatase (ATPase) ISWI as a key molecule in this process. ISWI actively erases the TATA binding protein from association with the nuclear matrix. Defining the biochemistry of global nuclear remodeling may facilitate the efficiency of cloning and other dedifferentiation events that establish new stem cell lineages.

Rapid assay of A1c-type glycosylated hemoglobin in blood of diabetic rats using fast protein liquid chromatography

AIM

To develop a fast protein liquid chromatography (FPLC) method for the assay of Alc-type glycosylated hemoglobin in diabetic rats.

METHODS

Venous blood was collected from rats. After the erythrocytes were washed and sedimented, the hemolysate was prepared and diluted with isotonic saline as a sample for the assay. Samples were then separated on Mono_S_HR_5/5 cation exchange column by a lithium chloride gradient elution system. The Alc-type glycosylated hemoglobin was monitored by measuring the absorbance at 415 nm.

RESULTS

The Alc-type glycosylated hemoglobin was well separated from total hemoglobin. The average HbAlc amount in diabetic rats was determined to be (3.6% +/- 0.6%, n = 7), while the corresponding figure in normal rats was (1.4% +/- 0.4%, n = 7, P < 0.01).

CONCLUSION

This FPLC method is easy, rapid and reproducible, and can be used for an assay of diabetic rat HbAlc to evaluate and screen new drugs for diabetes mellitus therapy.

Regional hyperthermia in the treatment of primary hepatic carcinoma

BACKGROUND AND OBJECTIVES

The purpose of this research was to investigate the clinical significance of regional hyperthermia in the treatment of primary hepatic carcinoma (PHC).

METHODS

The regional hyperthermia (60 degrees C) was used whenever there was suspicion of residual cancer tissues on the edge of the hepatic resection. The hyperthermia was maintained for about 5-20 min depending on the size and the amounts of residual nodulus. If there was obvious necrosis on the hyperthermia-treated site, the solidified tissues were removed. Otherwise, the solidified tissues were kept in situ.

RESULTS

There were 68 cases of PHC patients in this study. The patients were divided into 4 groups: A, lobectomy, 14 cases; B, lobectomy plus regional hyperthermia, 12 cases; C, regional hepatectomy, 16 cases; D, regional hepatectomy plus regional hyperthermia, 26 cases. All patients were followed after their operations. The mean survival time of the 4 groups was as follows: Group A, 346.5 days (186-921 days); Group B, 432.6 days (254-1189 days); Group C, 525.4 days (192-1016 days); and Group D, 1142 (from 318 days to seven years and two months) days. There were significant differences between Groups A and B (P < 0.01) and between Groups C and D (P < 0.01). It seems that regional hyperthermia on the hepatic resection edge can prolong patients' survival time.

CONCLUSIONS

Regional hyperthermia on the hepatic resection edge is helpful for prolonging patients' survival time in the treatment of primary hepatic carcinoma.