[Diagnostic value of endobronchial ultrasonography with a guide sheath for peripheral pulmonary ground glass opacity]

Objective: To explore the diagnostic value of endobronchial ultrasonography with a guide sheath (EBUS-GS) for peripheral pulmonary ground glass opacity (GGO). Methods: The clinical data of 27 consecutive patients with 27 GGOs diagnosed by EBUS-GS between November 2014 to December 2015 in our Cancer Hospital were retrospectively analyzed. The average age of these 27 patients, including 9 males and 18 females, was 59±11 years. The median lesion size of the 27 GGOs was 2.9±1.2 cm, including 24 mixed GGOs and 3 pure GGOs. EBUS images of all 27 GGOs were evaluated, cytological, histological and combination diagnosis analyzed, and complications observed. Results: Under thin bronchoscope, 2 out of 27 cases showed bronchial stenosis, 1 showed bronchial stenosis with mucosal swelling, and the other 24 did not show abnormalities. Twenty-five out of 27 GGOs were found by EBUS, including 22 cases of mGGO and 3 of pGGO. In these ultrasonic images of 22 mGGOs, 18 showed mixed blizzard sign, 3 showed diffusely heterogeneous acoustic shadow and 1showed blizzard sign. Ultrasonic images of 3 pGGOs all appeared as blizzard sign. Twenty-six cytological specimens were obtained, and 16 were diagnosed clearly. All 27 histological specimens were collected, and 18 were diagnosed clearly. Nineteen of 27 cases were diagnosed by combination of cytological and histological specimens. One complication of EBUS-GS with mild bleeding was observed, and hemorrhage was terminated by conservative treatment. Conclusions: EBUS-GS is valuable for GGO diagnosis with less complications and higher safety. GGO ultrasonic image manifested as mixed blizzard sign, blizzard sign or diffusely heterogeneous acoustic shadow.

[Efficacy and safety of pegylated interferon α-2b injection (Y shape, 40 kD) in treatment of patients with genotype 1/6 chronic hepatitis C]

Objective: To investigate the efficacy and safety of the new investigational drug pegylated interferon α-2b (Peg-IFN-α-2b) (Y shape, 40 kD) injection (180 µg/week) combined with ribavirin in the treatment of patients with genotype 1/6 chronic hepatitis C (CHC), with standard-dose Peg-IFN-α-2a combined with ribavirin as a positive control. Methods: A multicenter, randomized, open-label, and positive-controlled phase III clinical trial was performed. Eligible patients with genotype 1/6 CHC were screened out and randomly divided into Peg-IFN-α-2b(Y shape, 40kD) group and Peg-IFN-α-2a group at a ratio of 2:1. The patients in both groups were given oral ribavirin for 48 weeks in addition and then followed up for 24 weeks after drug withdrawal. Abbott Real Time HCV Genotype II was used to determine HCV genotype, and Cobas TaqMan quantitative real-time PCR was used to measure HCV RNA level at 0, 4, 12, 24, 48, and 72 weeks. Adverse events were recorded in detail. The primary efficacy endpoint was sustained virological response (SVR), and a non-inferiority test was also performed. Results: A total of 561 patients with genotype 1/6 CHC were enrolled, among whom 529 received treatment; 90.9% of these patients had genotype 1 CHC. The data of the full analysis set showed that SVR rate was 69.80% (95% CI 65.00%-74.60%) in the trial group and 74.16% (95% CI 67.73%-80.59%) in the control group (P = 0.297 0). The data of the per protocol set (PPS) showed that SVR rate was 80.63% (95% CI 76.04%-85.23%) in the trial group and 81.33% (95% CI 75.10%-87.57%) in the control group (P = 0.849 8), and the 95% CI of rate difference conformed to the non-inferiority standard. The analysis of the PPS population showed that of all subjects, 47.9% achieved rapid virologic response, with a positive predictive value of 93.8%. The incidence rate of adverse events was 96.30% in the trial group and 94.94% in the control group, and the incidence rate of serious adverse events was 5.13% in the trail group and 5.06% in the control group. Conclusion: In the regimen of Peg-IFN-α combined with ribavirin for the treatment of genotype 1/6 CHC, the new investigational drug Peg-IFN-α-2b(Y shape, 40 kD) has comparable clinical effect and safety to the control drug Peg-IFN-α-2a.

[Risk factors and survival analysis for synchronous esophageal carcinoma in patients with hypopharyngeal carcinoma]

Objective: To investigate the risk factors and survival status of hypopharyngeal carcinoma with synchronous second primary carcinoma of the esophagus. Methods: One hundred and sixty patients with newly diagnosed hypopharyngeal carcinoma from January 2009 to December 2012 were retrospectively reviewed. The clinical data, tumor-related information and follow-up results were collected and analyzed. Results: Forty-three synchronous esophageal carcinomas (27%) were detected in 160 patients with hypopharyngeal carcinoma, and most patients (72%) were at an early stage. On univariate analysis, the median age of less than 55 years old (χ(2)=4.525, P=0.033), excessive alcohol consumption (χ(2)=6.942, P=0.008) and invasion site more than 3 anatomical regions (χ(2)=21.503, P=0.000) had a significant correlation with the occurrence of synchronous esophageal carcinomas. Multivariate analysis showed that excessive alcohol consumption (OR=4.787, P=0.029) and invasion site more than 3 anatomical regions (OR=14.391, P=0.000) were independent risk factors. The median survival time was 26 months in 43 patients with synchronous esophageal carcinomas, which was significantly lower than that (58 months) in patients without secondary primary esophageal carcinomas (χ(2)=11.981, P=0.001). Conclusions: There is a high incidence of synchronous esophageal carcinoma in hypopharyngeal carcinoma patients, affecting the prognosis of hypopharyngeal carcinoma. Surveillance for esophageal carcinomas in patients with hypopharyngeal carcinoma, especially in excessive alcohol drinkers, is warranted.

HPV genotype analysis for women in Shaanxi Province of China

The aim of this study was to examine the subtype distribution of human papilloma virus (HPV) in women in the Shaanxi Province of China. A DNA chip, along with polymerase chain reaction amplification and reverse dot blot technology, was adopted to analyze the HPV genotypes of 22,937 cases of cervical cell specimens. The HPV infection rate was 18.70%, wherein high-risk, low-risk, and high- and low-risk multiple infection rates were 15.75, 2.96 and 1.91%, respectively. High-risk infections accounted for 84.20% of total infections. The rate of HPV infection in women with rural residence, high school education or less, a low income, or age over 40 years was significantly higher than that in the control group (negative HPV infection women). Of the 18 detected high-risk HPV subtypes, the most common in single infections were, in the order of prevalence, HPV16, 58, 18, 52, 33, and 56. For multiple high-risk infections, the most common subtypes in the order of prevalence were HPV16, 52, 58, 18, 56, and 33. Age was a factor in the rate of infection, as the 41-50-year age group had a significantly higher risk of infection than the other groups (P < 0.05). In multiple infections, double infections were common, accounting for 77.10% of multiple infections, and triple or more infections were more common in women aged 51-60 years. In Shaanxi Province, high-risk HPV infection in women was mainly attributed to rural residence, age over 40 years, low income, and low education level.

[Value of endobronchial ultrasound-guided transbronchial needle aspiration of enlarged mediastinal lymph nodes and analysis of false negative results]

Objective: To explore the diagnostic value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of enlarged mediastinal lymph nodes, and to analyze the reasons of false negative results of EBUS-TBNA. Methods: A retrospective analysis of the clinical and imaging data of 389 patients who underwent EBUS-TBNA for sampling enlarged hilar and mediastinal lymph nodes from October 2009 to October 2015 in Shandong Tumor Hospital, to evaluate its significance in the diagnosis of enlarged mediastinal lymph nodes, and to analyze the reasons of false negative results. Results: Among the 389 collected cases, positive biopsy results were obtained in 362 cases, and false negative results in 27 cases. The sensitivity, specificity, positive predictive value and negative predictive value were 92.9%, 100%, 100% and 25.0%, respectively. There was a positive correlation between the size of lymph node and biopsy positive rate (P=0.021). The subcarinal lymph nodes had the highest positive rate (97.7%), followed by the paratracheal lymph nodes (91.2%), with a statistically significant difference (P=0.006). The positive rates obtained by cytology (88.7%) and pathology (92.5%, ) showed no significant difference (P=0.065). The positive rate of EBUS-TBNA was not correlated with pathological types (P=0.932). Needle types (21G, 22G) had no significant effect on diagnosis accuracy (P=0.142). Conclusions: EBUS-TBNA is a practical technology for diagnosis of enlarged mediastinal lymph nodes, with unique characteristics such as minimally invasiveness, local anesthesia, good safety and repeatability. Along with the accumulation of surgical experience, improvement of operative skills, more close cooperation between surgeons, cytologists and pathologists, false negative results will be reduced and positive rate of EBUS-TBNA examination will be further improved.

[Laparoscopic versus open wedge resection of gastric gastrointestinal stromal tumors: a non-randomized case-matched study]

OBJECTIVE

To investigate the safety and feasibility of laparoscopic wedge resection for gastric gastrointestinal stromal tumors (GIST).

METHODS

One hundred GIST patients treated in our department between 2010 and 2014 were retrospectively enrolled, and their clinicopathological data were reviewed. Fifty patients underwent laparoscopic wedge resection, and open surgery cases were 1∶1 matched by tumor diameter. The clinicopathological characteristics, perioperative related factors, postoperative nutritional status and short-term outcome were compared between the two groups.

RESULTS

Among the clinicopathological characteristics, only the age was of statistical significance (61.58±10.43 vs. 56.40±9.82, P=0.012). Over fifty percent of the tumors occurred in the gastric body. Although the short-term survival did not show statistical significance, the laparoscopic group showed predominant advantages in estimated blood loss [(48.60±48.89) ml vs. (137.60±140.69) ml, P<0.001], average hospital stay[ (12.14±4.32) d vs.(17.22±7.11) d, P<0.001], oral intake time[ (3.76±1.73)d vs. (6.28±3.73)d, P<0.01], decline of prealbumin [(0.07±0.04)g/L vs. (0.11±0.05)g/L, P<0.001)], decline of transferrin [(0.51±0.29)g/L vs. (0.64±0.30)g/L, P=0.034]and complication (2.0% vs. 14.0%, P=0.027).

CONCLUSION

Laparoscopic wedge resection is feasible and safe for GIST surgery, allows a rapid recovery and having a better nutritional status in patients, and is a less invasive approach for patients.

Prevalence of human papillomavirus genotypes among women with cervical lesions in the Shaanxi Province of China

This study aimed to investigate human papilloma virus (HPV) genotypes among women with cervical lesions in Shaanxi Province, China, to obtain information regarding cervical lesion prevention and treatment. The study included 4508 HPV-positive subjects; cervical swab specimens were collected and tested for HPV infection status and HPV genotypes using polymerase chain reaction and reverse dot-blot hybridization. Women positive for HPV with cervical lesions, including chronic cervicitis, cervical intraepithelial neoplasia, and cervical squamous cell carcinoma (SCC), were examined; HPV-positive women with no cervical lesions were controls. Data were pooled and weighted estimates have been presented. For women with no cervical lesions and positive for one HPV genotype, HPV 52, 16, 58, 81, 33, and 56 were the most common; for multiple-HPV genotype infection, HPV 16, 52, 6, 18, 58, and 66 were the most common. Collectively, HPV 16, 58, 52, 18, 33, and 81 were the most common in women with cervical lesions. HPV 16 comprised 26.71% of single-genotype and 15.64% of multiple-genotype infections. The proportion of HPV-16-positive cases was 29.15%, which was the highest among all HPV genotypes (P < 0.01). Single-HPV genotype infection was the most common in cervical HPV infection (77.48%); infection with two HPV genotypes comprised 72.22% of multiple-genotype infections. The proportion of single-low-risk HPV genotype infections decreased with increase in cervical lesion severity; there were no single- or multiple-low-risk genotype HPV infections in cervical SCC patients. The proportion of multiple-genotype HPV infections with at least one high-risk genotype increased with cervical lesion severity.

Stimulation of bacterial biofilms on Th17 immune cells

We investigated the role of bacterial biofilms in stimulating T helper 17 (Th17) cells in infected organisms. The formation of bacterial biofilms isolated from clinical lavage fluid samples was measured. Th17 cells and interleukin 17 (IL-17) levels in the peripheral blood of healthy individuals, people infected by biofilm bacteria, people infected by non-biofilm bacteria, and in the lavage fluid from people infected by bacteria were determined. Differences in those data were tested using the SPSS 17.0 statistical software. Th17 cells and IL-17 levels in the peripheral blood of biofilm bacteria-infected people, non-biofilm bacteria-infected people, and healthy controls were 0.59 ± 0.18% and 108.8 ± 20.5 pg/mL; 0.58 ± 0.18% and 100.1 ± 20.7 pg/mL; and 0.55 ± 0.17% and 100.0 ± 21.4 pg/mL, respectively; there were no statistically significant differences (P > 0.05). Th17 cells and IL-17 levels in the lavage fluid of biofilm bacteria-infected people and non-biofilm bacteria-infected people were 1.37 ± 0.34% and 157.4 ± 30.8 pg/mL; and 1.11 ± 0.21% and 136.2 ± 24.3 mg/mL, respectively; the differences were statistically significant (P < 0.05). Bacterial biofilms can increase the expression levels of Th17 cells and IL-17 in local infections; this may be the mechanism by which chronic injuries are caused by biofilm infections.

Using hydrological simulation to detect human-disturbed epoch in runoff series

Runoff in major rivers in China has been decreasing in recent decades, mainly due to climate change and human activity. River basin managers have a critical interest in detecting and diagnosing non-stationaries in runoff time series. Here we use a rainfall runoff model-based approach to identify the human-disturbed periods of the record. The method is applied to the Kuye River catchment, located in the Loess Plateau, China. The SimHyd model performs well for simulation of monthly natural discharges, and the method suggests that discernable human influence began in 1980. Anthropogenic effects were detectable several years earlier at the downstream stations than the upstream stations, consistent with pace and timing of soil and water conservation measures implemented across the Kuye River catchment.

The Metabolizable Energy Value, Standardized Ileal Digestibility of Amino Acids in Soybean Meal, Soy Protein Concentrate and Fermented Soybean Meal, and the Application of These Products in Early-weaned Piglets

Three experiments were conducted to evaluate the metabolizable energy (ME) value, standardized ileal digestibility (SID) of amino acids (AA) of soybean meal (SBM), soy protein concentrate (SPC) and fermented soybean meal (FSBM), and the application of these products in early-weaned piglets. In Exp. 1, four barrows with initial body weight (BW) of 14.2±1.4 kg were used in a 4×4 Latin square design. The diet 1 contained corn as the only energy source. The other three diets replaced 25% of corn in diet 1 with one of the three soybean products, and the digestable energy (DE) and ME contents were determined by difference. In Exp. 2, four barrows (initial BW of 18.2±1.5 kg) were fitted with ileal T-cannulas and allotted to a 4×4 Latin square design. Three cornstarch-based diets were formulated using each of the soybean products as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. In Exp. 3, ninety six piglets (initial BW of 5.6±0.9 kg) weaned at 21±2 d were blocked by weight and assigned to one of three treatments for a 21-d growth performance study. The control diet was based on corn and SBM, the two treatments’ diets contained either 10% SPC or FSBM and were formulated to same SID lysine to ME ratio of 3.6 g/Mcal. The results showed that the ME content of SPC was greater than SBM (p<0.05). The SID of most AA in SPC was greater than the SID of AA in SBM (p<0.05). For the essential AA, the SID of histidine, isoleucine, leucine, lysine and threonine in FSBM were greater than in SBM (p<0.05). Even though they were fed same SID lysine to ME ratio of 3.6 g/Mcal diets, pigs fed SPC and FSBM diets had greater weight gain, G:F (p<0.05) and better fecal score (p<0.05) than pigs fed SBM diet. In conclusion, SPC showed a higher ME content and SID of AA than the SBM. SID of some essential AA in FSBM was higher than SBM and was similar with SPC. But the lower antigenic proteins and anti-nutritional factors content in SPC and FSBM may be the main factors affecting the performance of early-weaned piglets rather than the increased ME content and SID of AA.

Effects of single cell protein replacing fish meal in diet on growth performance, nutrient digestibility and intestinal morphology in weaned pigs

Three experiments were conducted to evaluate the ME value, standardized ileal digestibility (SID) of amino acids (AA) of fish meal, and the effects of single cell protein (Prosin and Protide) replacing fish meal in diet on growth performance, nutrient digestibility and intestinal morphology in weaned piglets. In Exp. 1, twenty-four barrows with initial BW of 30.8±2.6 kg were allotted to one of four dietary treatments. Diet 1 contained corn as the only energy source. The other three diets replaced 20% of the corn in diet 1 with one of the three protein feeds (fish meal, Prosin and Protide), and the DE and ME contents were determined by difference. In Exp. 2, eight barrows (initial BW of 25.6±3.2 kg) were fitted with ileal T-cannulas and allotted to a replicated 4×4 Latin square design. Three cornstarch-based diets were formulated using each of the protein feeds as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. In Exp. 3, one hundred and eighty piglets (initial BW of 7.95±1.59 kg) weaned at 28±2 d were blocked by weight and assigned to one of five treatments for a 28-d growth performance study, each treatment was fed to six pens with six pigs (three barrows and three gilts) per pen. The five treatments consisted of the control group (CON), which was a corn-soybean meal diet containing 5% fish meal, and the other four treatments, which replaced a set amount of fish meal with either Prosin (2.5% or 5%) or Protide (2.5% or 5%). The diets were formulated to provide same nutrient levels. The results showed that on a DM basis, both of the DE and ME contents were lower in Prosin and Protide than that of fish meal (p<0.05). The SID of CP and all essential AA were greater in fish meal than in Prosin and Protide (p<0.05). The pigs fed CON diet had greater weight gain and lower feed conversion rate (FCR) than pigs fed 5% Prosin and 5% Protide diets (p<0.05). The digestibility of CP was greater in pigs fed CON, 2.5% Prosin and 2.5% Protide diets than the pigs fed 5% Prosin and 5% Protide diets (p<0.05). Villus height in jejunum and ileum, and villus height to crypt depth ratio in the jejunum were higher (p<0.05) in pigs fed CON, 2.5% Prosin and 2.5% Protide diets compared with the 5% Prosin and 5% Protide diets. Pigs fed CON diet had greater villus height to crypt depth ratio in the ileum than the pigs fed 5% Prosin and 5% Protide diets (p<0.05). In conclusion, although Prosin and Protide contained lower ME content and SID of AA than fish meal, Prosin and Protide replacing 50% of fish meal in diet with identical nutrient levels could obtain similar performance, nutrient digestibility and intestinal morphology in weaned pigs.

Step terrace tuned anisotropic transport properties of highly epitaxial LaBaCo2O5.5+δ thin films on vicinal SrTiO3 substrates

Highly epitaxial LaBaCo2O5.5+δ (LBCO) thin films were grown on different miscut (001) SrTiO3 substrates (miscut angle of 0.5°, 3.0°, and 5.0°) to study the substrate surface step terrace effect on the in-plane electrical transport properties. The microstructure studies by X-ray diffraction and transmission electron microscopy indicate that the as-grown films are A-site disordered cubic perovskite structures with the c-axis highly oriented along the film growth direction. The four-probe scanning tunneling microscopy (STM) studies show that the LBCO thin films grown on the vicinal SrTiO3 substrates have a typical semiconductor behavior with the substrate surface terrace step inducing anisotropic electronic transport properties. These results indicate that in highly epitaxial thin films the surface terrace step induced local strains can play an important role in controlling the electronic transport properties and the anisotropic nature.

Metabolisable Energy, In situ Rumen Degradation and In vitro Fermentation Characteristics of Linted Cottonseed Hulls, Delinted Cottonseed Hulls and Cottonseed Linter Residue

Dietary supplementation with conventional linted cottonseed hulls (LCSH) is a common practice in livestock production all over the world. However, supplementation with mechanically delinted cottonseed hulls (DCSH) and cottonseed linter residue (CLR) is uncommon. Cottonseed by-products, including LCSH, DCSH and CLR, were assessed by chemical analysis, an in situ nylon bag technique, an in vitro cumulative gas production technique and in vitro enzyme procedure. The crude protein (CP) content of CLR (302 g/kg dry matter (DM)) was approximately 3 times that of LCSH and 5 times that of DCSH. The crude fat content was approximately 3 times higher in CLR (269 g/kg DM) than in LCSH and 4 times higher than in DCSH. Neutral detergent fibre (311 g/kg DM) and acid detergent fibre (243 g/kg DM) contents of CLR were less than half those of DCSH or LCSH. Metabolisable energy, estimated by in vitro gas production and chemical analyses, ranked as follows: CLR (12.69 kJ/kg DM)>LCSH (7.32 kJ/kg DM)>DCSH (5.82 kJ/kg DM). The in situ degradation trial showed that the highest values of effective degradability of DM and CP were obtained for CLR (p<0.05). The in vitro disappearance of ruminal DM ranked as follows: CLR>LCSH>DCSH (p<0.05). The lowest digestibility was observed for DCSH with a two-step in vitro digestion procedure (p<0.05). The potential gas production in the batch cultures did not differ for any of the three cottonseed by-product feeds. The highest concentration of total volatile fatty acids was observed in CLR after a 72 h incubation (p<0.05). The molar portions of methane were similar between all three treatments, with an average gas production of 22% (molar). The CLR contained a higher level of CP than did LCSH and DCSH, and CLR fermentation produced more propionate. The DCSH and LCSH had more NDF and ADF, which fermented into greater amounts of acetate.

Using an abnormal increase in postexercise systolic blood pressure to diagnose coronary artery disease in gerontal patients

Data from 66 patients ≥ 60 years old with suspected coronary artery disease (CAD) were studied to determine the diagnostic value of an abnormal increase in postexercise systolic blood pressure (SBP) for detecting CAD in gerontal patients. Treadmill exercise testing (TET) and selective coronary angiography (CAG) were carried out and SBP was measured pre-TET and at each minute during a 6-min post-TET recovery phase. Abnormal increase in postexercise SBP was defined as a higher SBP compared with that measured earlier during the 6-min post-TET period. An abnormal increase of ≥ 7 mmHg in postexercise SBP had a statistically significantly better specificity, and also showed higher sensitivity and accuracy, than ST-segment depression ≥ 1 mV in identifying gerontal patients with CAD. The combination of ST-segment depression and abnormal SBP resulted in further improvement of the specificity for detecting CAD. It is concluded that measurement of abnormal increase in postexercise SBP may be a sensitive indicator of gerontal CAD.

First report of human infection by Rhodoplanes sp., Alphaproteobacteria in China

We isolated a novel strain of Alphaproteobacteria from a patient, who had medical history of chronic rhinitis for more than twenty years and recently experienced local skin abscess and ulcer. He eventually died of multiple organ failure due to multi-antibiotics resistance. We identified the microorganism by 16SrRNA sequencing and found that it belonged to the genus Rhodoplanes. It was named as Rhodoplanes sp. strain ZLJ-0. It is resumed that Rhodoplanes sp. strain ZLJ-0 might be an emerging human pathogen involving in unknown febrile conditions and could cause local infection of any tissues or organs. Differential diagnosis of febrile patients should be conducted in clinical practice and research on emerging pathogens of Alphaproteobacteria should be performed to determine the epidemiology, clinical symptoms and pathogenic features of these pathogens.

An experimental method to verify soil conservation by check dams on the Loess Plateau, China

A successful experiment with a physical model requires necessary conditions of similarity. This study presents an experimental method with a semi-scale physical model. The model is used to monitor and verify soil conservation by check dams in a small watershed on the Loess Plateau of China. During experiments, the model-prototype ratio of geomorphic variables was kept constant under each rainfall event. Consequently, experimental data are available for verification of soil erosion processes in the field and for predicting soil loss in a model watershed with check dams. Thus, it can predict the amount of soil loss in a catchment. This study also mentions four criteria: similarities of watershed geometry, grain size and bare land, Froude number (Fr) for rainfall event, and soil erosion in downscaled models. The efficacy of the proposed method was confirmed using these criteria in two different downscaled model experiments. The B-Model, a large scale model, simulates watershed prototype. The two small scale models, D(a) and D(b), have different erosion rates, but are the same size. These two models simulate hydraulic processes in the B-Model. Experiment results show that while soil loss in the small scale models was converted by multiplying the soil loss scale number, it was very close to that of the B-Model. Obviously, with a semi-scale physical model, experiments are available to verify and predict soil loss in a small watershed area with check dam system on the Loess Plateau, China.

Hyper-methylation of RIZ1 tumor suppressor gene is involved in the early tumorigenesis of hepatocellular carcinoma

The retinoblastoma protein-interacting zinc finger gene RIZ1 is a putative tumor suppressor gene, and the inactivation of the RIZ1 is frequently found in tumors through a loss of mRNA expression. In order to understand the role of RIZ1 inactivation in the tumorigenesis of hepatocellular carcinoma (HCC), we detected the RIZ1 promoter methylation status in 39 HCCs using a methylation specific PCR (MSP) method, and carried out LOH study with marker P704. We also assessed the associations between the methylation status and clinicopathological parameters, tumor size, tumor differentiation, and fractional allelic loss (FAL). The results showed that the RIZ1 promoter methylated both in advanced tumors (>3 cm), (18/31, 58.0%) and in early tumors (<3 cm), (4/8, 50.0%). There were 54.6% (12/22) tumors with hyper-methylation in the low FAL group and 45.5% (10/22) in the high FAL group. Moreover, the DNA methylation of the RIZ1 promoter was found not only in the poorly differentiated tumors (12/22, 54.6%), but also in the well differentiated tumors (10/22, 45.5%). Among the 22 HCCs (22/39, 56.4%) that showed hyper-methylation at the RIZ1 promoter region, 3 cases showed biallelic methylation. Interestingly, one case showed hyper-methylation on one allele and a loss of heterozygosity (LOH) on the other allele. In other words, 4 HCCs showed the biallelic inactivation of the RIZ1. These results suggest that the inactivation of the RIZ1 by DNA methylation at its promoter region is involved in the tumorigenesis of HCC, particularly in the early stage of disease.

IPCS: an integrated process control system for enhanced in-situ bioremediation

To date, there has been little or no research related to process control of subsurface remediation systems. In this study, a framework to develop an integrated process control system for improving remediation efficiencies and reducing operating costs was proposed based on physical and numerical models, stepwise cluster analysis, non-linear optimization and artificial neural networks. Process control for enhanced in-situ bioremediation was accomplished through incorporating the developed forecasters and optimizers with methods of genetic algorithm and neural networks modeling. Application of the proposed approach to a bioremediation process in a pilot-scale system indicated that it was effective in dynamic optimization and real-time process control of the sophisticated bioremediation systems.

An integrated numerical and physical modeling system for an enhanced in situ bioremediation process

Groundwater contamination due to releases of petroleum products is a major environmental concern in many urban districts and industrial zones. Over the past years, a few studies were undertaken to address in situ bioremediation processes coupled with contaminant transport in two- or three-dimensional domains. However, they were concentrated on natural attenuation processes for petroleum contaminants or enhanced in situ bioremediation processes in laboratory columns. In this study, an integrated numerical and physical modeling system is developed for simulating an enhanced in situ biodegradation (EISB) process coupled with three-dimensional multiphase multicomponent flow and transport simulation in a multi-dimensional pilot-scale physical model. The designed pilot-scale physical model is effective in tackling natural attenuation and EISB processes for site remediation. The simulation results demonstrate that the developed system is effective in modeling the EISB process, and can thus be used for investigating the effects of various uncertainties.

Role of cytosolic liver fatty acid binding protein in hepatocellular oxidative stress: effect of dexamethasone and clofibrate treatment

The presence of cysteine and methionine groups together with an ability to bind long-chain fatty acid (LCFA) oxidation products makes liver fatty acid binding protein (L-FABP) an attractive candidate against hepatocellular oxidative stress. In this report, we show that pharmacological treatment directed at modulating L-FABP level affected hepatocellular oxidant status. L-FABP expressing 1548-hepatoma cells, treated with dexamethasone or clofibrate, decreased and increased intracellular L-FABP levels, respectively. Oxidative stress was induced by H2O2 incubation or hypoxia-reoxygenation. The fluorescent marker, dichlorofluorescein (DCF), was employed to measure intracellular reactive oxygen species (ROS). Hepatocellular damage was assessed by lactate dehydrogenase (LDH) level. Dexamethasone treatment resulted in a significant increase in DCF fluorescence with higher LDH release compared to control cells. Clofibrate treatment, however, resulted in a significant decrease in both parameters (p<0.05). Drug treatments did not affect cytosolic activities of glutathione peroxidase (GPx), superoxide dismutase (SOD), or catalase suggesting that the differences between treated and control cells may likely be associated with varying L-FABP levels. We conclude that L-FABP may act as an effective endogenous cytoprotectant against hepatocellular oxidative stress.

Membrane binding proteins are the major determinants for the hepatocellular transmembrane flux of long-chain fatty acids bound to albumin

PURPOSE

The hepatic transmembrane flux of long-chain fatty acids (LCFA) occurs through passive and fatty acid transport protein facilitated processes from blood. The extent that these transport processes can be related to the unbound and protein-bound fractions of LCFA in blood is not clear.

METHODS

We used hepatocyte suspensions, hepatoma monolayers, and perfused rat livers to quantitate the transport of purified [(3)H]palmitate ([(3)H]PA) and 12-(N-methyl)-N-[(7-nitrobenz-2oxa-1,3-diazol-4yl-)amino]octadecanoicacid (12-NBDS) from solutions with a constant unbound LCFA concentration with varying bovine serum albumin (BSA) concentrations and in the presence and absence of antisera raised against cytosolic liver fatty acid binding protein (L-FABP).

RESULTS

In the absence of L-FABP antisera, using an unbound ligand concentration that was adjusted to remain constant at each BSA concentration, hepatocyte [(3)H]PA and 12-NBDS uptake rates increased linearly with an increase in BSA concentration (p < 0.0001). In the presence of L-FABP antisera, [(3)H]PA uptake showed a greater reduction in the presence of 100 muM BSA than 5 muM BSA. The calculated permeability surface area product (PS) confirmed that both unbound and bound fractions of LCFA contributed to the overall flux, but only the PS for the protein-bound fraction was reduced in the presence of L-FABP antisera. In situ rat liver perfusion studies showed that the only rate process for the disposition of [(3)H]PA in the liver inhibited by L-FABP antisera was that for influx, as defined by PS, and that it reduced PS in the perfused liver by 42%.

CONCLUSION

These results suggest that, at physiological albumin concentrations, most of the LCFA uptake is mediated from that bound to albumin by a hepatocyte basolateral membrane transport protein, and uptake of unbound LCFA occurring by passive diffusion contributes a minor component.

Assessing the cellular transmembrane electrical potential difference on the hepatic uptake of palmitate

Understanding the driving forces for the hepatic uptake of endogenous and exogenous substrates in isolated cells and organs is fundamental to describing the underlying hepatic physiology/pharmacology. In this study we investigated whether uptake of plasma protein-bound [3H]-palmitate across the hepatocyte wall is governed by the transmembrane electrical potential difference (PD). Uptake was studied in isolated hepatocytes and isolated perfused rat livers (IPL). Protein-binding and vasoactive properties of the different perfusates were determined using in vitro heptane/buffer partitioning studies and the multiple indicator dilution (MID) technique in the IPL, respectively. Altering hepatocyte PD by perfusate ion substitution resulted in either a substantial depolarization (-14 +/- 1 mV, n = 12, mean +/- S.E., substituting choline for Na+) or hyperpolarization (-46 +/- 3 mV, n = 12, mean +/- S.E., substituting nitrate for Cl-). Perfusate ion substitution also affected the equilibrium binding constant for the palmitate-albumin complex. IPL studies suggested that, other than with gluconate buffer, hepatic [3H]-palmitate extraction was not affected by the buffer used, implying PD was not a determinant of extraction. [3H]-Palmitate extraction was much lower (p < 0.05) when gluconate was substituted for Cl- ion. This work contrasts with that for the extraction of [3H]-alanine where hepatic extraction fraction was significantly reduced during depolarization. Changing the albumin concentration did not affect hepatocyte PD, and [3H]-palmitate clearance into isolated hepatocytes was not affected by the buffers used. MID studies with vascular and extravascular references revealed that, with the gluconate substituted buffer, the extravascular volume possibly increased the diffusional path length thus explaining reduced [3H]-palmitate extraction fraction in the IPL.

Cladistic analysis of human apolipoprotein a4 polymorphisms in relation to quantitative plasma lipid risk factors of coronary heart disease

Genetic variation in several genes involved in lipid metabolism is known to affect population variation in quantitative lipid risk factor profiles for coronary heart disease (CHD). The apolipoprotein A-IV gene (APOA4) is one such candidate gene. We genotyped five polymorphisms in the APOA4 gene (codon 127, codon 130, codon347, codon 360 and 3' VNTR) and investigated their impact on plasma lipid trait levels in three populations comprising 604 U.S. non-Hispanic Whites (NHWs), 408 U.S. Hispanics and 708 Nigerian Blacks. Cladistic analysis was carried out to identify 5-site haplotypes that were associated with significant phenotypic differences in each population. The distribution of APOA4 genotypes was significantly different between ethnic groups. The Africans were monomorphic for two of the five sites (codons 130 and 360), but possess a unique 12 bp insertion that was not observed in NHWs and Hispanics. Due to linkage disequilibrium between the sites, only 6 haplotypes were observed in NHWs and Hispanics, and 4 in Africans. Several gender-and ethnic-specific associations between genotypes and plasma lipid traits were observed when single sites were used. Several haplotypes were identified by cladistic analysis that may carry functional mutations that affect plasma lipid trait levels.

Resistance to granzyme B-mediated cytochrome c release in Bak-deficient cells

Granzyme B (GrB), a serine protease with substrate specificity similar to the caspase family, is a major component of granule-mediated cytotoxicity of T lymphocytes. Although GrB can directly activate caspases, it induces apoptosis predominantly via Bid cleavage, mitochondrial outer membrane permeabilization, and cytochrome c release. To study the molecular regulators for GrB-mediated mitochondrial apoptotic events, we used a CTL-free cytotoxicity system, wherein target cells are treated with purified GrB and replication-deficient adenovirus (Ad). We report here that the Bcl-2 proapoptotic family member, Bak, plays a dominant role in GrB-mediated mitochondrial apoptotic events. A variant of Jurkat cells, deficient in Bak expression, was resistant to GrB/Ad-mediated apoptosis, as determined by lack of membranous phosphatidylserine exposure, lack of DNA breaks, lack of mitochondrial outer membrane permeabilization, and unchanged expression of inner mitochondrial membrane cardiolipin. The resistance of Bak-deficient cells to GrB/Ad cytotoxicity was reversed by transduction of the Bak gene into these cells. The requirement for both Bid and Bak, was further demonstrated in a cell-free system using purified mitochondria and S-100 cytosol. Purified mitochondria from Bid knockout mice, but not from Bax knockout mice, failed to release cytochrome c in response to autologous S-100 and GrB. Also, Bak-deficient mitochondria did not release cytochrome c in response to GrB-treated cytosol unless recombinant Bak protein was added. These results are the first to report a role for Bak in GrB-mediated mitochondrial apoptosis. This study demonstrates that GrB-cleaved Bid, which differs in size and site of cleavage from caspase-8-cleaved Bid, utilizes Bak for cytochrome c release, and therefore, suggests that deficiency in Bak may serve as a mechanism of immune evasion for tumor or viral infected cells.

Hepatocyte [3H]-palmitate uptake: effect of albumin surface charge modification

The role of plasma proteins on the cellular uptake of lipophilic substrates has perplexed investigators for many years. We tested the hypothesis that an ionic interaction between the protein-ligand complex and hepatocyte surface may be responsible for supplying more ligand to the cell for uptake. The surface-charged groups on albumin were modified to yield proteins having a range of isoelectric points (ALB, ALBs, ALBm, ALBe had values of 4.8-5.0, 4.5-4.7, 3.0-3.5, 8.4-8.6, respectively). [3H]-Palmitate uptake studies were performed with adult rat hepatocyte suspensions using similar unbound ligand fractions in the presence of the different binding proteins. Mass spectrometry, isoelectric focusing (pI), and heptane:water partitioning were used to determine protein molecular weight, pI, and protein-palmitate equilibrium binding constant, respectively. Hepatocyte [3H]-palmitate clearance in the presence of ALBs and ALBm were significantly lower (p < 0.05) than ALB, whereas [3H]-palmitate clearance in the presence of ALBe was significantly higher (p < 0.05) than ALB. The data were consistent with the notion that ionic interactions between extracellular protein-ligand complexes and the hepatocyte surface facilitate the uptake of long-chain fatty acids.

Hepatocyte [3H]-palmitate uptake: effect of albumin surface charge modification

The role of plasma proteins on the cellular uptake of lipophilic substrates has perplexed investigators for many years. We tested the hypothesis that an ionic interaction between the protein–ligand complex and hepatocyte surface may be responsible for supplying more ligand to the cell for uptake. The surface-charged groups on albumin were modified to yield proteins having a range of isoelectric points (ALB, ALBs, ALBm, ALBe had values of 4.8–5.0, 4.5–4.7, 3.0–3.5, 8.4–8.6, respectively). [3H]-Palmitate uptake studies were performed with adult rat hepatocyte suspensions using similar unbound ligand fractions in the presence of the different binding proteins. Mass spectrometry, isoelectric focusing (pI), and heptane : water partitioning were used to determine protein molecular weight, pI, and protein-palmitate equilibrium binding constant, respectively. Hepatocyte [3H]-palmitate clearance in the presence of ALBs and ALBm were significantly lower (p < 0.05) than ALB, whereas [3H]-palmitate clearance in the presence of ALBe was significantly higher (p < 0.05) than ALB. The data were consistent with the notion that ionic interactions between extracellular protein–ligand complexes and the hepatocyte surface facilitate the uptake of long-chain fatty acids.Key words: uptake, long-chain fatty acid, hepatic, protein, albumin, surface charge, facilitation, ionic interaction.

A role for mitochondrial Bak in apoptotic response to anticancer drugs

In the present study a clonal Jurkat cell line deficient in expression of Bak was used to analyze the role of Bak in cytochrome c release from mitochondria. The Bak-deficient T leukemic cells were resistant to apoptosis induced by UV, staurosporin, VP-16, bleomycin, or cisplatin. In contrast to wild type Jurkat cells, these Bak-deficient cells did not respond to UV or treatment with these anticancer drugs by membranous phosphatidylserine exposure, DNA breaks, activation of caspases, or release of mitochondrial cytochrome c. The block in the apoptotic cascade was in the mitochondrial mechanism for cytochrome c release because purified mitochondria from Bak-deficient cells failed to release cytochrome c or apoptosis-inducing factor in response to recombinant Bax or truncated Bid. The resistance of Bak-deficient cells to VP-16 was reversed by transduction of the Bak gene into these cells. Also, the cytochrome c releasing capability of the Bak-deficient mitochondria was restored by insertion of recombinant Bak protein into purified mitochondria. Following mitochondrial localization, low dose recombinant Bak restored the mitochondrial release of cytochrome c in response to Bax; at increased doses it induced cytochrome c release itself. The function of Bak is independent of Bid and Bax because recombinant Bak induced cytochrome c release from mitochondria purified from Bax(-/-), Bid(-/-), or Bid(-/-) Bax(-/-) mice. Together, our findings suggest that Bak plays a key role in the apoptotic machinery of cytochrome c release and thus in the chemoresistance of human T leukemic cells.

Palmitate uptake by neonatal rat myocytes and hepatocytes. Role of extracellular protein

The role of extracellular binding proteins in the rate of [3H]palmitate uptake by neonatal cardiac myocytes and hepatocytes was investigated using a model-independent approach. Binding proteins used in this study included alpha1-acid glycoprotein [isoelectric point (pI) approximately 2.7], conalbumin (pI approximately 6.4), lysozyme (pI approximately 11.0), albumin (pI approximately 4.9), and albumin which had been modified to yield proteins with pI values of 3.5, 4.7, 7.5 and 8.6. All uptake studies were conducted at similar unbound ligand fractions. There was a linear relationship between the rate of neonatal hepatocyte [3H]palmitate clearance and protein pI (r2 = 0.98). In contrast, there was an overall poor relationship between neonatal cardiac myocyte [3H]palmitate-clearance rate and protein pI (r2 = 0.48). However, the relationship improved when the data on [3H]palmitate-clearance were analyzed using only the modified albumins. The study indicates that an ionic interaction between extracellular proteins and the hepatocyte surface enhances the overall uptake of [3H]palmitate. This interaction may be limited to albumin for neonatal cardiac myocytes.

Cardiac apoptosis in burned rats with delayed fluid resuscitation

Clinical and experimental studies have shown that delayed fluid resuscitation postburn decreases heart function. We hypothesized that apoptosis occurs in the cardiomyocyte in this condition. To investigate this hypothesis, rats were burned, fluid resuscitation was delayed, and the integrity of cardiac genomic DNA in the burned rats was determined with an LM-PCR Ladder Assay kit. DNA fragmentation shown as DNA ladders on gels, the hallmark of apoptosis, was found in the heart tissue of these rats. In the early phase of delayed fluid resuscitation, the nuclear factor kappa B (NF-kappa B) was examined using an electrophoretic mobility shift assay and was found to be activated. In comparison with burned rats with immediate fluid resuscitation, nitric oxide levels in hearts from burned rats with delayed fluid resuscitation were significantly lower (P<0.01). These results suggest that apoptosis may be an important pathway for cardiac injury, which may result from the activation of NF-kappa B and decreased nitric oxide levels.

Tumor necrosis factor-alpha-promoted expression of Bcl-2 and inhibition of mitochondrial cytochrome c release mediate resistance of mature dendritic cells to melanoma-induced apoptosis

Melanoma escapes host defenses through a variety of means, including the elimination of immune effector cells within the tumor microenvironment. We have reported recently that murine and human tumors including melanoma induce premature apoptosis of dendritic cells both in vitro and in vivo. In this study, we have demonstrated that overexpression of the Bcl-2 protein family member Bcl-xL rescued murine dendritic cells (DCs) from melanoma-induced death in vitro. Another successful protection approach was tumor necrosis factor (TNF)-alpha-promoted sustained expression of the antiapoptotic protein Bcl-2 within dendritic cells. This effect of TNF-alpha was mediated by inhibition of mitochondrial cytochrome c release. Thus, both Bcl-xL and Bcl-2 enhance survival of dendritic cells within the tumor microenvironment. In addition, mature DCs were more resistant to melanoma-induced apoptosis than immature dendritic cells. This finding suggests a stage-dependent sensitivity of DCs to tumor-induced cell death. We conclude that: (a) mature DCs might be more suitable for the use of cancer vaccination; and (b) Bcl-2 protein family members such as Bcl-xL and Bcl-2 rescue DCs from tumor-induced premature apoptosis.

[1.4 kb 5' flanking region of class I patatin directs tuber-specific gus expression in potato (Solanum tuberosum L.)]

Binary vectors pPATIs (with partial signal sequence) and pPATI (without signal sequence) were constructed by fusing 1.4 kb 5' flanking regions of Class I patatin gene with GUS. Transient GUS expression was observed in in vitro tuber slices bombarded with pPATI. These constructs were then introduced into potato (cv. Desiree) via Agrobacterium tumefaciens transformation. Transgenic potato plants were confirmed by X-Gluc staining and PCR. Using in vitro tuberization system, GUS activities were assayed by fluorescence. It was shown that, in plants transformed with PATI-GUS, GUS specific activities were about 10-20 fold higher in tubers than in stems. Increased sucrose concentration could not induce PATI-GUS expression, but light enhanced PATI-GUS expression in cultured shoots.

Apoptosis-resistant mitochondria in T cells selected for resistance to Fas signaling

Jurkat leukemic T cells are highly sensitive to the extrinsic pathways of apoptosis induced via the death receptor Fas or tumor necrosis factor-related apoptosis-inducing ligand as well as to the intrinsic/mitochondrial pathways of death induced by VP-16 or staurosporin. We report here that clonal Jurkat cell lines selected for resistance to Fas-induced apoptosis were cross-resistant to VP-16 or staurosporin. Each of the apoptotic pathways was blocked at an apical phase, where common regulators of apoptosis have not yet been defined. The Fas pathway was blocked at the level of caspase-8, whereas the intrinsic pathway was blocked at the mitochondria. No processing or activity of caspases was detected in resistant cells in response to either Fas-cross-linking or VP-16 treatment. Also, no apoptosis-associated alterations in the mitochondrial inner membrane, outer membrane, or matrix were detected in resistant Jurkat cells treated with VP-16. Thus, no changes in permeability transition, loss in inner membrane cardiolipin, generation of reactive oxygen species, or release of cytochrome c were observed in resistant cells treated with VP-16. Further, unlike purified mitochondria from wild type cells, those obtained from resistant cells did not release cytochrome c or apoptosis-inducing factor in response to recombinant Bax or truncated Bid. These results identify a defect in mitochondria ability to release intermembrane proteins in response to Bid or Bax as a mechanism of resistance to chemotherapeuetic drugs. Further, the selection of VP-16-resistant mitochondria via elimination of Fas-susceptible cells may suggest the existence of a shared regulatory component between the extrinsic and intrinsic pathways of apoptosis.

[30-year experiences on early detection and treatment of esophageal cancer in high risk areas]

The author had conducted the clinical study on early diagnosis and early therapy of esophageal cancer (EC) in the area of high prevalence for more than 30 years. In the endoscopic survey, 742 patients were diagnosed as early EC from 22,285 participants. The endoscopic appearance of the mucosa in early EC was classified into three types: (1) change of mucosa color: red and white area; (2) Increased thickness and change of the vascular pattern of the mucosa; (3) mucosa morphology: erosion, plaque, coarseness and nodular. Iodine staining under endoscopic examination had promoted the early detection of EC and precancerous lesions. Since 307 patients with EC at early stage (65 carcinoma in situ, 95 intramucosal carcinoma, and 147 submucosal carcinoma) had undergone esophagectomy. There were no lymphatic metastasis in carcinoma in situ, however there were 2 cases (2.11%) of intramucosal carcinoma and 27 cases (18.37%) of submucosal carcinoma with lymph node metastasis. 24-year follow-up, results showed that 5-year survival rate is 84.1% and a 10-year survival rate is 72.9% among the cases of esophagectomy. A 5-year survival rate is 100% in 22 cases followed up for full five years among 141 cases with endoscopic mucosectomy. According to this study, severe dysplasia and some moderate dysplasia were precancerous lesions. Should these precancerous cases be treated, the cancerization risk of target population would reduce dramatically and the incidence of EC would be decreased down to 2/3.

Tumor-induced apoptosis of T cells: amplification by a mitochondrial cascade

We have recently reported that apoptosis of T cells induced by squamous cell carcinoma of the head and neck (SCCHN) is partly Fas dependent. This tumor-induced T-cell death is mediated by the activities of caspase-8 and caspase-3 and is partially inhibited by antibodies to either Fas or Fas ligand. We report here that in contrast to apoptosis induced by agonistic anti-Fas antibody (Ab), the tumor-induced apoptotic cascade in Jurkat cells is significantly amplified by a mitochondrial loop. The involvement of mitochondria in tumor-induced apoptosis of T cells was demonstrated by changes in mitochondrial permeability transition as assessed by 3,3'-dihexiloxadicarbocyanine staining, by cleavage of cytosolic BID and its translocation to the mitochondria, by release of cytochrome c to the cytosol, and by the presence of active subunits of caspase-9 in Jurkat T cells cocultured with tumor cells. To further elucidate the significance of mitochondria in tumor-induced T-cell death, we investigated the effects of various inhibitors of the mitochondrial pathway. Specific antioxidants, as well as two inhibitors of mitochondria permeability transition, bongkrekic acid and cyclosporin A, significantly blocked the DNA degradation induced in Jurkat T cells by SCCHN cells. However, these inhibitors had no effect on cells triggered by anti-Fas Ab. Furthermore, a cell-permeable inhibitor of caspase-9, Ac-LEHD.CHO, which did not inhibit T-cell apoptosis induced by anti-Fas Ab, markedly inhibited apoptosis induced by etoposide or by coculture of Jurkat with SCCHN cells. These findings demonstrate that apoptotic cascades induced in Jurkat T lymphocytes by anti-Fas Ab or tumor cells are differentially susceptible to a panel of inhibitors of mitochondrial apoptotic events. It appears that besides the Fas-mediated pathway, additional mitochondria-dependent cascades are involved in apoptosis of tumor-associated lymphocytes. Inhibition of mitochondria-dependent cascades of caspase activation should be considered to enhance the success of immunotherapy or vaccination protocols in cancer.

Impact of genetic polymorphisms in cytochrome P450 2E1 and glutathione S-transferases M1, T1, and P1 on susceptibility to esophageal cancer among high-risk individuals in China

Esophageal cancer, which is prevalent in China, is believed to be induced by environmental carcinogens such as nitrosamines and other agents. The disproportionate geographical distribution of this cancer among individuals suggests a role for gene-environment interactions in developing the disease. We have shown in our preliminary study that a genetic polymorphism in cytochrome P450 2E1 (CYP2E1) that is known to activate nitrosamines may be a susceptibility factor involved in the early events leading to the development of esophageal cancer (Lin et al., Cancer Epidemiol. Biomark. Prev., 7: 1013-1018, 1998). This relatively larger study was conducted to compare the results with our previous findings. One hundred and fifty cases with esophageal cancer, 146 cases with esophageal dysplasia, and 150 normal controls were residents of Linxian, China, a high-risk area. Genomic DNA samples were assayed for restriction fragment length polymorphisms in the CYP2E1 and GSTP1 loci by PCR amplification followed by digestion with RsaI and Alw26I, respectively. Deletion of the GSTM1 and GSTT1 genes was detected by multiplex PCR. The distribution of CYP2E1 c1/c1 allele frequency was found to be significantly different between controls (44.0%) and cases with cancer (71.3%) or cases with dysplasia (70.6%; P < 0.0001). Individuals having the c1/c1 genotype were at a 3.1-fold [95% confidence interval (CI), 2.4-3.9] increased risk of developing dysplasia and a 3.2-fold (95% CI, 2.5-4.1) increased risk of developing squamous cell carcinoma of the esophagus. Although polymorphisms in the GSTT1 and GSTP1 were not significantly different between cases with cancer or cases with dysplasia and controls, the frequency of the GSTM1 non-null (+/+ and +/0) genotypes appeared to be overrepresented in cases with cancer compared with controls (odds ratio, 2.3; 95% CI, 1.8-3.0). Furthermore, a joint effect of the CYP2E1 c1/c1 genotype and GSTM1 non-null genotype on the cancer risk was observed, showing an odds ratio of 8.5 (95% CI, 3.7-19.9). These results demonstrate that CYP2E1 and perhaps GSTM1 are genetic determinants in the development of squamous cell carcinoma of the esophagus.

Antibiotic-heparin lock: in vitro antibiotic stability combined with heparin in a central venous catheter

Long-term hemodialysis frequently requires vascular access through central venous catheters (CVCs). Infection related to these catheters is a significant complication. The use of an antibiotic-heparin lock could decrease the risks associated with infected permanent catheters. As an initial step in developing an antibiotic-heparin lock, we investigated the in vitro stability of antibiotic-heparin combinations in CVCs. Initially, cefazolin, vancomycin, ceftazidime, ciprofloxacin 10 mg/ml each, and gentamicin 5 mg/ml were incubated separately in glass test tubes in the dark at 37 degrees C for 72 hours. Samples were analyzed spectrophotometrically for stability at 24-hour intervals. The procedure was repeated with the addition of heparin (final concentration 5000 U/ml in glass test tubes), and the combination was also examined in CVCs. High-performance liquid chromatography analysis was conducted on the antibiotic-heparin combinations at 72 hours to confirm the spectrophotometric results. Ciprofloxacin produced an immediate precipitate with the addition of heparin and was not analyzed further. Absorbance values decreased for all antibiotics, with the greatest decreases at 72 hours for cefazolin (27.4%), vancomycin (29.7%), ceftazidime (40.2%), and gentamicin (8%) when combined with heparin. These decreases were postulated to be secondary to adsorption of the antibiotics to the luminal surface of the catheters because submitting the catheters to ultrasound with 1% sodium bicarbonate and analyzing the resulting solution for absorbance revealed that some of the drug was recovered. Although free antibiotic in CVC solution was reduced, the concentration should be sufficient (approximately 5 mg/ml) to decrease the frequency of infections associated with CVCs. We conclude that the concentrations of vancomycin, ceftazidime, cefazolin, or gentamicin used in our study should be sufficient for an antibiotic-heparin lock.

Inhibitor of apoptosis protein hILP undergoes caspase-mediated cleavage during T lymphocyte apoptosis

Several endogenous or viral inhibitors of apoptosis, including Bcl-2, Bcl-xL, FLIP, p35, and CrmA, have been shown to be cleaved by caspases during apoptosis. In this study, we demonstrate that the endogenous inhibitor of apoptosis, hILP/XIAP, is also cleaved in apoptotic T lymphocytes, generating at least one prominent fragment of 29 kDa. This p29 cleaved fragment was detected in Jurkat cells induced to apoptose by anti-Fas antibody, staurosporin, or VP-16. The cleavage of hILP appears to be caspase mediated because the production of the p29 protein was inhibited by the pan-caspase peptide inhibitor, Z-VAD.FMK. In Jurkat cells engineered to overexpress CrmA, cleavage of hILP in response to anti-Fas antibody or staurosporin was inhibited, whereas overexpression of Bcl-2 abrogated the cleavage in response to VP-16. Cleavage of hILP was also observed in cell-free reactions using in vitro translated hILP and recombinant caspase-3 or -7. Moreover, we found that the p29 hILP fragment retained the ability to bind caspase-3 and -7, as shown previously for full-length or BIR-2 hILP. The p29 cleavage product was also detected during T-cell receptor-mediated apoptosis in peripheral blood lymphocytes from normal donors. Furthermore, tumor-associated T lymphocytes purified from ascites of patients with ovarian cancer expressed fragmented hILP, which was not detected in control T cells purified from peripheral blood of normal donors. Our results suggest that the cleavage of hILP represents an important event in apoptosis of T lymphocytes in both normal and pathological in vivo settings.

[Isolation of a gene related to trichosanthin-induced apoptosis (GRETA)]

Disturbance of the apoptosis-related signaling pathway is regarded as one of the critical factors for tumorigenesis. Isolation of the genes involved in the process of apoptosis would be thereby helpful to explore the mechanism of tumor transformation and to develop novel therapeutic approaches. Here we report a gene fragment GRETA, the gene related to trichosanthin-induced apoptosis, isolated from a leukemia cell line U937 undergoing apoptosis induced by a plant protein Trichosanhin (TCS). A 293bp segment of GRETA was revealed to be 78.3% homologous to Bruton's tyrosine kinase at nucleic acid level. And Northern blot analysis showed that three messengers of RNA with the size of about 0.8-kb, 2.0-kb and 7.0-kb, respectively, were detected in TCS-untreated U937 cells when probed with GRETA, but there were only 0.8-kb and 2.0-kb transcripts appeared in apoptotic U937 cells. In addition, the abundance of each transcript changed apparently. The 0.8-kb transcript, for example, was the main band in Northern analysis in apoptotic U937 cells while was only detected marginally in TCS-untreated cells. These data suggested a possible relationship between the alternative splicing patterns of GRETA and the apoptosis.

Constitutive and inducible nitric oxide synthases after dynorphin-induced spinal cord injury

It has recently been demonstrated that selective inhibition of both neuronal constitutive and inducible nitric oxide synthases (ncNOS and iNOS) is neuroprotective in a model of dynorphin (Dyn) A(1-17)-induced spinal cord injury. In the present study, various methods including the conversion of 3H-L-arginine to 3H-citrulline, immunohistochemistry and in situ hybridization are employed to determine the temporal profiles of the enzymatic activities, immunoreactivities, and mRNA expression for both ncNOS and iNOS after intrathecal injection of a neurotoxic dose (20 nmol) of Dyn A(1-17). The expression of ncNOS immunoreactivity and mRNA increased as early as 30 min after injection and persisted for 1-4 h. At 24-48 h, the number of ncNOS positive cells remained elevated while most neurons died. The cNOS enzymatic activity in the ventral spinal cord also significantly increased at 30 min 48 h, but no significant changes in the dorsal spinal cord were observed. However, iNOS mRNA expression increased later at 2 h, iNOS immunoreactivity and enzymatic activity increased later at 4 h and persisted for 24-48 h after injection of 20 nmol Dyn A(1-17). These results indicate that both ncNOS and iNOS are associated with Dyn-induced spinal cord injury, with ncNOS predominantly involved at an early stage and iNOS at a later stage.

Huperzine-A in capsules and tablets for treating patients with Alzheimer disease

AIM

To compare the efficacy and safety between huperzine-A (Hup) in capsules and tablets for treating patients with Alzheimer disease (AD).

METHODS

Using multicenter, prospective, double-blind, double-mimic, parallel, positive controlled and randomized methods, 60 patients meeting with the NINCDS-ARDRA criteria of AD were divided into 2 equal groups. Patients in the capsule group received 4 capsules of Hup (each contains 50 micrograms) and 4 tablets of placebo (lactose and starch inside); while the tablet group received 4 tablets of Hup (each contains 50 micrograms) and 4 capsules of placebo, p.o., twice a day for 60 d. All the patients were evaluated with a lot of related ranting scales, and physiological and laboratory examination.

RESULTS

There were significant differences (P < 0.01) on all the psychological evaluations between 'before' and 'after' the 60-d trial of 2 groups, but there was no significant difference between 2 groups by group t test (P > 0.05). The changes of oxygen free radicals in 2 groups showed marked improvement. No severe side effect besides moderate to mild nausea was found in both groups.

CONCLUSION

There is equal efficacy and safety between Hup in capsule and tablet for treating patients with AD, and Hup can reduce the pathological changes of the oxygen free radicals in the plasma and erythrocytes of patients with AD.

Altered transmembrane ionic flux in hepatocytes isolated from cirrhotic rats

BACKGROUND/AIMS

Although cirrhosis is known to be associated with many hepatocyte abnormalities, there is no well-established model to study the cellular drug uptake process independent of hemodynamic effects. The purpose of the present study was to test the following hypothesis: hepatocytes isolated from cirrhotic animals may be used as a model to study the cellular abnormalities associated with cirrhosis. Our hypothesis was tested by comparing the membrane potential (PD) of hepatocytes in anesthetized healthy and cirrhotic animals, and the PD and [3H]palmitic acid clearance rate of hepatocytes isolated from healthy and cirrhotic animals.

METHODS

Mild to moderate cirrhosis was induced in female Sprague-Dawley rats by CCl4 administration. PD was recorded in anesthetized animals using intracellular microelectrodes. Hepatocytes from those livers were subsequently isolated by collagenase perfusion for further determinations of PD and [3H]palmitic acid uptake.

RESULTS

The mean (+/-SEM) hepatocyte PD from intact rat livers was 38+/-1 mV (control) and -32+/-1 mV (cirrhosis; n=6/group, p<0.01). The PD (mean+/-SEM) in isolated hepatocytes was -21+/-1 mV (control) and -15+/-1 mV (cirrhosis, n=13/group, p<0.01). The clearance rate of [3H]palmitic acid was lower in hepatocytes isolated from cirrhotic animals (26%) than in those isolated from healthy control animals (p<0.01).

CONCLUSION

The results of this study indicate that hepatocytes isolated from cirrhotic animals may be used to study the cellular abnormalities associated with cirrhosis.

Dual role for nitric oxide in dynorphin spinal neurotoxicity

The pharmacological effects of nitric oxide synthase (NOS) inhibitors, NO donor, and NOS substrate on dynorphin(Dyn) A(1-17) spinal neurotoxicity were studied. Intrathecal (i.t.) pretreatment with both 7-nitroindazole 1 micromol, a selective neuronal constitutive NOS (ncNOS) inhibitor, and aminoguanidine 1 micromol, a selective inducible NOS (iNOS) inhibitor, 10 min prior to i.t. Dyn A(1-17) 20 nmol significantly ameliorated Dyn-induced neurological outcome. Both 7-nitroindazole and aminoguanidine significantly antagonized the increases of cNOS and iNOS activities measured by conversion of 3H-L-arginine to 3H-L-citrulline in the ventral spinal cord, and blocked the Dyn-induced increases of ncNOS-immunoreactivity in the ventral horn cells 4 h after i.t. Dyn A(1-17) 20 nmol. Pretreatment with Nomega-nitro-L-arginine methyl ester (L-NAME) 1 micromol, a cNOS inhibitor nonselective to both ncNOS and endothelial NOS (ecNOS), did not antagonize Dyn A(1-17) 20 nmol-induced permanent paraplegia but aggravated Dyn A(1-17) 10 nmol-induced transient paralysis and caused permanent paraplegia. Pretreatment with L-NAME 1 micromol 10 min before i.t. Dyn A(1-17) 1.25 and 2.5 nmol, which produced no significant motor dysfunction alone, induced transient paralysis in seven out of 12 and five out of seven rats, respectively. L-NAME 1 micromol plus Dyn A(1-17) 10 nmol induced ncNOS-immunoreactivity expression in ventral horn cells. Both low and high doses of aminoguanidine (0.2-30 micromol) did not affect spinal motor function, but high doses of L-NAME (5-20 micromol) induced dose-dependent hindlimb and tail paralysis associated with spinal cord injury in normal rats. Pretreatment with low-dose Spermine NONOate, a controlled NO releaser, 0.1 and 0.5 micromol 10 min before i.t. Dyn A(1-17) 20 nmol, significantly prevented Dyn spinal neurotoxicity, and high-dose Spermine NONOate 2 micromol i.t. per se induced transient and incomplete paraplegia. But pretreatment with L-Arg 10 micromol 10 min before Dyn A(1-17) 20 nmol produced only partial blockade of Dyn-induced paraplegia. These results demonstrated that relatively specific inhibition of ncNOS and iNOS block Dyn-induced increases in cNOS and iNOS activities and ncNOS-immunoreactivity in ventral spinal cord, but nonspecific inhibition of ncNOS and ecNOS aggravated Dyn spinal neurotoxicity. It suggested that both ncNOS and iNOS play an important role, but ecNOS might be beneficial in Dyn spinal neurotoxicity. Moderate production of NO (at vascular level) has an apparently neuroprotective effect, and overproduction of NO (at cellular level) induces neurotoxicity.

Binding of [3H]palmitate to BSA

Determination of the BSA-palmitate high-affinity binding constant (Ka) traditionally relied on the heptane-water partitioning technique. We used this technique to calculate Ka for the BSA-[3H]palmitate complex, to determine if Ka was independent of protein concentration, and to determine if the unbound [3H]palmitate concentration is constant at different BSA concentrations using constant BSA-to-palmitate molar ratios (range 1:1 to 1:4). After extensive extraction of non-[3H]palmitate radiolabeled substances, the heptane-to-buffer partition ratio, in the absence of BSA, was 702 +/- 19 (mean +/- SD, n = 6). This value was much lower than the predicted value of 1,376 and was highly dependent on which phase (organic or aqueous) initially contained the [3H]palmitic acid. The data were consistent with the notion of self-association of [3H]palmitate in the aqueous phase. Ka for the BSA-[3H]palmitate complex was determined to be similar (2.2 +/- 0.1) x 10(8) M-1 (mean +/- SD, P > 0.05) at all BSA concentrations studied. At each BSA-to-palmitate molar ratio, the equilibrium unbound ligand concentration was constant only at low BSA concentrations (<10 microM) and at low BSA-to-palmitate molar ratios (i.e., 1:1 and 1:2). At higher BSA concentrations and molar ratios, the unbound ligand concentration increased with an increase in protein concentration. Hepatocyte uptake using the manufacturer-supplied radiolabeled product was significantly higher than with the purified product, suggesting that a non-[3H]palmitate radiolabel is also a substrate for the uptake process.

Mucosal iodine staining improves endoscopic visualization of squamous dysplasia and squamous cell carcinoma of the esophagus in Linxian, China

BACKGROUND

In previous studies in the high risk population of Linxian, China, the majority of foci of high grade (moderate and severe) squamous dysplasia (HGD) and invasive squamous carcinoma (CA) of the esophagus were associated with endoscopically visible lesions that could be targeted for biopsy, but some foci of HGD were missed by routine endoscopic examination. This study examined whether spraying the mucosa with Lugol's iodine solution, which stains normal epithelium brown but leaves dysplasia and carcinoma unstained, could improve endoscopic detection and delineation of these lesions.

METHODS

Two hundred twenty-five Linxian adults with balloon cytologic evidence of dysplasia or carcinoma underwent endoscopy. All visible lesions were described and photographed before and after staining with 1.2% Lugol's iodine solution. Biopsies were taken from all lesions visible before staining, from all unstained lesions (USLs) after applying the stain, and from representative control areas of stained mucosa.

RESULTS

Two hundred fifty-three USLs and 255 control sites were biopsied. No complications occurred. Ninety-four biopsy sites contained HGD and 20 contained CA. Before staining, the sensitivity of visible lesions for identifying HGD or CA was 62%, and the specificity was 79%. After staining, the sensitivity of USLs for identifying HGD or CA was 96%, and the specificity was 63%. Eighty-eight percent of the HGD and CA lesions were larger or more clearly defined after staining. The diagnostic lesions in 17 of 31 patients with moderate dysplasia (55%), 8 of 35 patients with severe dysplasia (23%), and none of the 19 patients with invasive carcinoma (0%) were identified only after staining.

CONCLUSIONS

Mucosal iodine staining improved endoscopic detection and delineation of HGD and CA in these patients. This simple technique is highly sensitive for identifying these precursor and invasive squamous lesions, and it should be used whenever optimal visualization of squamous mucosal abnormalities is required.

Mucosal iodine staining improves endoscopic visualization of squamous dysplasia and squamous cell carcinoma of the esophagus in Linxian, China

BACKGROUND

In previous studies in the high risk population of Linxian, China, the majority of foci of high grade (moderate and severe) squamous dysplasia (HGD) and invasive squamous carcinoma (CA) of the esophagus were associated with endoscopically visible lesions that could be targeted for biopsy, but some foci of HGD were missed by routine endoscopic examination. This study examined whether spraying the mucosa with Lugol's iodine solution, which stains normal epithelium brown but leaves dysplasia and carcinoma unstained, could improve endoscopic detection and delineation of these lesions.

METHODS

Two hundred twenty-five Linxian adults with balloon cytologic evidence of dysplasia or carcinoma underwent endoscopy. All visible lesions were described and photographed before and after staining with 1.2% Lugol's iodine solution. Biopsies were taken from all lesions visible before staining, from all unstained lesions (USLs) after applying the stain, and from representative control areas of stained mucosa.

RESULTS

Two hundred fifty-three USLs and 255 control sites were biopsied. No complications occurred. Ninety-four biopsy sites contained HGD and 20 contained CA. Before staining, the sensitivity of visible lesions for identifying HGD or CA was 62%, and the specificity was 79%. After staining, the sensitivity of USLs for identifying HGD or CA was 96%, and the specificity was 63%. Eighty-eight percent of the HGD and CA lesions were larger or more clearly defined after staining. The diagnostic lesions in 17 of 31 patients with moderate dysplasia (55%), 8 of 35 patients with severe dysplasia (23%), and none of the 19 patients with invasive carcinoma (0%) were identified only after staining.

CONCLUSIONS

Mucosal iodine staining improved endoscopic detection and delineation of HGD and CA in these patients. This simple technique is highly sensitive for identifying these precursor and invasive squamous lesions, and it should be used whenever optimal visualization of squamous mucosal abnormalities is required.

Mucosal iodine staining improves endoscopic visualization of squamous dysplasia and squamous cell carcinoma of the esophagus in Linxian, China

BACKGROUND

In previous studies in the high risk population of Linxian, China, the majority of foci of high grade (moderate and severe) squamous dysplasia (HGD) and invasive squamous carcinoma (CA) of the esophagus were associated with endoscopically visible lesions that could be targeted for biopsy, but some foci of HGD were missed by routine endoscopic examination. This study examined whether spraying the mucosa with Lugol's iodine solution, which stains normal epithelium brown but leaves dysplasia and carcinoma unstained, could improve endoscopic detection and delineation of these lesions.

METHODS

Two hundred twenty-five Linxian adults with balloon cytologic evidence of dysplasia or carcinoma underwent endoscopy. All visible lesions were described and photographed before and after staining with 1.2% Lugol's iodine solution. Biopsies were taken from all lesions visible before staining, from all unstained lesions (USLs) after applying the stain, and from representative control areas of stained mucosa.

RESULTS

Two hundred fifty-three USLs and 255 control sites were biopsied. No complications occurred. Ninety-four biopsy sites contained HGD and 20 contained CA. Before staining, the sensitivity of visible lesions for identifying HGD or CA was 62%, and the specificity was 79%. After staining, the sensitivity of USLs for identifying HGD or CA was 96%, and the specificity was 63%. Eighty-eight percent of the HGD and CA lesions were larger or more clearly defined after staining. The diagnostic lesions in 17 of 31 patients with moderate dysplasia (55%), 8 of 35 patients with severe dysplasia (23%), and none of the 19 patients with invasive carcinoma (0%) were identified only after staining.

CONCLUSIONS

Mucosal iodine staining improved endoscopic detection and delineation of HGD and CA in these patients. This simple technique is highly sensitive for identifying these precursor and invasive squamous lesions, and it should be used whenever optimal visualization of squamous mucosal abnormalities is required.

Do nutritional supplements lower the risk of stroke or hypertension?

Between 1986 and 1991, 29,584 persons took part in a randomized nutritional intervention trial in Linxian, China, an area whose residents had chronically low intakes of several nutrients and high rates of esophageal and gastric cardia cancer as well as stroke. Using a one-half replicate of a 2(4) factorial design, we randomized individuals to one of eight groups which received combinations of four supplements: retinol and zinc (factor A); riboflavin and niacin (factor B); vitamin C and molybdenum (factor C); and beta-carotene, alpha-tocopherol (vitamin E), and selenium (factor D). Deaths that occurred during 5 years of supplementation were ascertained and classified according to cause. At the end of the supplementation period, we measured blood pressure readings and determined the prevalence of hypertension. Participants who received factor D had reductions in total mortality (9%) and total cancer mortality (13%). These individuals also had the largest reduction in stroke mortality (relative risk = 0.91; 95% confidence interval = 0.76-1.07). End-of-trial hypertension, however, was not less prevalent among those receiving factor D. Our findings contrast with the larger reductions in stroke death and hypertension found in a parallel trial of Linxian subjects with esophageal dysplasia who received a multivitamin/mineral supplement, suggesting an effect largely derived from nutrients other than those received in the present study.

Cytologic detection of esophageal squamous cell carcinoma and precursor lesions using balloon and sponge samplers in asymptomatic adults in Linxian, China

BACKGROUND

The principal reason for the poor prognosis of esophageal carcinoma is that most tumors are asymptomatic and go undetected until they are unresectable. Previous studies have shown that cytologic screening of asymptomatic high risk individuals can detect curable esophageal carcinomas and precursor lesions, but the sensitivity of such screening is not well documented. The current study evaluated the sensitivity and specificity of currently available balloon and sponge cytologic samplers for detecting biopsy-proven squamous dysplasia and carcinoma in asymptomatic individuals from a high risk population in Linxian, China.

METHODS

Asymptomatic adults were examined with both balloon and sponge samplers, in random order, followed by endoscopy with mucosal iodine staining and biopsy of all unstained lesions. The cytology slides were interpreted using the criteria of the Bethesda System. The balloon and sponge cytologic diagnoses (test) were compared with the biopsy diagnosis (truth) in each patient to estimate the sensitivity and specificity of each sampler.

RESULTS

Of the 439 patients with adequate biopsies, 123 (28%) had histologic squamous dysplasia and 16 (4%) had an invasive squamous carcinoma. The sensitivities/specificities of the balloon and sponge were 44%/99% and 18%/100%, respectively, for detecting biopsy-proven squamous cell carcinoma, and 47%/81% and 24%/92%, respectively, for identifying squamous dysplasia or carcinoma.

CONCLUSIONS

In this study, the balloon sampler was more sensitive than the sponge sampler for detecting esophageal squamous disease, but both techniques were less than optimal. Improved samplers and/or cytologic criteria should increase the sensitivities observed in this baseline study.

Cytologic detection of esophageal squamous cell carcinoma and precursor lesions using balloon and sponge samplers in asymptomatic adults in Linxian, China

BACKGROUND

The principal reason for the poor prognosis of esophageal carcinoma is that most tumors are asymptomatic and go undetected until they are unresectable. Previous studies have shown that cytologic screening of asymptomatic high risk individuals can detect curable esophageal carcinomas and precursor lesions, but the sensitivity of such screening is not well documented. The current study evaluated the sensitivity and specificity of currently available balloon and sponge cytologic samplers for detecting biopsy-proven squamous dysplasia and carcinoma in asymptomatic individuals from a high risk population in Linxian, China.

METHODS

Asymptomatic adults were examined with both balloon and sponge samplers, in random order, followed by endoscopy with mucosal iodine staining and biopsy of all unstained lesions. The cytology slides were interpreted using the criteria of the Bethesda System. The balloon and sponge cytologic diagnoses (test) were compared with the biopsy diagnosis (truth) in each patient to estimate the sensitivity and specificity of each sampler.

RESULTS

Of the 439 patients with adequate biopsies, 123 (28%) had histologic squamous dysplasia and 16 (4%) had an invasive squamous carcinoma. The sensitivities/specificities of the balloon and sponge were 44%/99% and 18%/100%, respectively, for detecting biopsy-proven squamous cell carcinoma, and 47%/81% and 24%/92%, respectively, for identifying squamous dysplasia or carcinoma.

CONCLUSIONS

In this study, the balloon sampler was more sensitive than the sponge sampler for detecting esophageal squamous disease, but both techniques were less than optimal. Improved samplers and/or cytologic criteria should increase the sensitivities observed in this baseline study.