[Analysis of Bacterial Communities and Antibiotic Resistance Genes in the Aquaculture Area of Changli County]

In order to understand the distribution of microorganisms and various antibiotic resistance genes in the aquaculture area of Changli County, Qinhuangdao, high-throughput sequencing technology was used in this study. We utilized 16S rDNA gene sequencing and metagenome sequencing methods to analyze the seawater, sediment, and gut contents of the local fish Synechogobius hasta in the aquaculture area in spring. The results showed that Proteobacteria, Firmicutes, and Bacteroidota were the dominant bacteria in seawater; and Proteobacteria, Crenarchaeota, Acidobacter, and Actinobaciota were rich in the sediment; whereas Proteobacteria, Cyanobacteria, Firmicutes, and Bacteroidota were in relatively high abundance in fish gut contents. The microbial diversity of sediment samples was the most abundant, followed by seawater samples, and the microbial diversity of fish intestinal contents was the lowest. Moreover, the microbial diversity of similar samples was relatively similar, and the microbial diversity of different types of samples was quite different. For samples at different sites, there were significant differences between seawater samples at each site, and there were small differences between sediment samples at each site, and some sediment sample groups did not have significant differences in microbial composition. In all sample groups, five β-lactam antibiotic resistance genes (blaOXA-325, cepS, blaCARB-20, blaOXA-55, and blaTRU-1) and four aminoglycoside antibiotic resistance genes[aac(6')-IIb, amrA, aac(6')-Ie-aph(2″)-Ia, and aph(3')-Vc] were detected. There was also a certain correlation between antibiotic resistance genes and microbial communities.

The jigsaw puzzle of pedigree: whole-genome resequencing reveals genetic diversity and ancestral lineage in Sunong black pigs

The Sunong black pig is a new composite breed under development generated from Chinese indigenous pig breeds (i.e., Taihu and Huai) and intensive pig breeds (i.e., Landrace and Berkshire), which is an important genetic material for studying breeding mechanisms. However, there is currently limited knowledge about the genetic structure and germplasm characteristics of Sunong black pigs. To comprehensively understand their genetic composition and ancestry proportions, we performed population structure and local ancestry inference analysis based on whole-genome sequencing information. The results showed that Sunong black pigs could be clustered independently into a group, whose pedigree was intermediate between indigenous and commercial pig breeds, but closer to commercial pigs. Furthermore, local ancestry inference analysis revealed that Sunong black pigs inherited immune and reproductive traits from indigenous pig breeds, including CC and CXC chemokine family, Toll-like receptor family, IFN gene family, ESR1, AREG and EREG gene, while growth and development-related traits were inherited from commercial pig breeds, including IGF1 and GSY2 gene. Overall, Sunong black pigs have formed a relatively stable genome structure with some advantageous traits inherited from their ancestral breeds. This study deepened the understanding of the breeding mechanism of Sunong black pigs and provided a reference for cross-breeding programmes in livestock.

Genome-wide scans for selection signatures in indigenous pigs revealed candidate genes relating to heat tolerance

Heat stress is a major problem that constrains pig productivity. Understanding and identifying adaptation to heat stress has been the focus of recent studies, and the identification of genome-wide selection signatures can provide insights into the mechanisms of environmental adaptation. Here, we generated whole-genome re-sequencing data from six Chinese indigenous pig populations to identify genomic regions with selection signatures related to heat tolerance using multiple methods: three methods for intra-population analyses (Integrated Haplotype Score, Runs of Homozygosity and Nucleotide diversity Analysis) and three methods for inter-population analyses (Fixation index (F_ST), Cross-population Composite Likelihood Ratio and Cross-population Extended Haplotype Homozygosity). In total, 1 966 796 single nucleotide polymorphisms were identified in this study. Genetic structure analyses and F_ST indicated differentiation among these breeds. Based on information on the location environment, the six breeds were divided into heat and cold groups. By combining two or more approaches for selection signatures, outlier signals in overlapping regions were identified as candidate selection regions. A total of 163 candidate genes were identified, of which, 29 were associated with heat stress injury and anti-inflammatory effects. These candidate genes were further associated with 78 Gene Ontology functional terms and 30 Kyoto Encyclopedia of Genes and Genomes pathways in enrichment analysis (P < 0.05). Some of these have clear relevance to heat resistance, such as the AMPK signalling pathway and the mTOR signalling pathway. The results improve our understanding of the selection mechanisms responsible for heat resistance in pigs and provide new insights of introgression in heat adaptation.

[Clinical efficacy of spinal cord stimulation for the patients with diabetic foot]

Objective: To observe the clinical efficacy of spinal cord stimulation (SCS) in the treatment of diabetic foot (DF). Methods: Sixteen patients who were diagnosed with DF and treated with SCS from the Department of Pain Medicine of the First Affiliated Hospital, China Medical University from October 2015 to October 2018 were retrospectively analyzed. Visual analogue scale (VAS), 36-item short form health survey (SF-36), transcutaneous oxygen partial pressure (TcPO₂) and skin temperature of lower limbs were compared before and after treatment, and the complications were recorded. Results: Among the 16 patients, 14 were equipped with implantable pulse generator (IPG). The VAS scores decreased significantly from 7.5±1.2 before treatment to 2.6±0.8, 2.0±0.7, 1.6±0.6, 1.0±0.9, 0.9±0.9 at 1 day, 1 week, 3 months, 6 months and 12 months after electrode implantation respectively (all P<0.05). At 12 months after treatment, the parameters of SF-36 were significantly different from those before treatment (all P<0.05). The TcPO₂ was (23±5) mmHg before treatment and (38±6) mmHg at 1 week after treatment, with a statistical difference (P<0.05), and the temperature of lower limbs increased significantly (P<0.05). No serious complications were observed in all patients. Conclusion: SCS can relieve the pain of patients with DF, improve the microcirculation and blood supply of lower limbs, and thus promote the quality of life, with rare serious complications.

[Influence of fasting duration on blood volume status of pediatric patients evaluated by ultrasonic technique]

Objective: To evaluate the influence of preoperative fasting duration on blood volume status of pediatric patients during induction based on ultrasonic technique. Methods: One hundred and ten pediatric patients, scheduled for elective operation in the Second Affiliated Hospital & Yuying Children's Hospital, were recruited during January and October in 2018. After sedation by inhalation of sevoflurane, the maximum (expiratory) and minimum (inspiratory) diameter of inferior vena cava (IVC(max), IVC(min)) and aorta velocity-time integral (VTI) in apical five-chamber cardiac view were measured with an ultrasound machine. Respiratory variabilities of these parameters were further calculated. Furthermore, passive leg raising (PLR) test was performed and above measurements/calculations were repeated. The correlation between the duration of fasting and IVC respiratory variations index (IVC(RVI)) or aortic VTI variability (ΔVTI) was then analyzed. Results: Before PLR, IVC(max), IVC(min) and IVC(RVI) were (0.78±0.19), (0.43±0.15) cm and 0.45±0.12, respectively. After PLR, IVC(max) and IVC(min) increased to (0.94±0.20), (0.55±0.18) cm, while IVC(RVI) decreased to 0.42±0.13, the differences were statistically significant (t=15.66, 10.85, 3.14, all P<0.05). However, IVC(max), IVC(min) and IVC(RVI) were not significantly correlated with the duration of fasting analyzed by linear regression (before PLR: r=0.052, 0.163, 0.171; after PLR, r=0.062, 0.169, 0.165, all P>0.05). Before PLR, expiratory aortic VTI (VTI(max)), inspiratory aortic VTI (VTI(min)) and ΔVTI were 21±5, 17±4 and 17±8, respectively. After PLR, the VTI(max) and VTI(min) significantly increased to 23±5 and 19±4 (t=13.60, 10.43, all P<0.05), but ΔVTI was not changed significantly, which was 17±8(t=0.34, P>0.05). Linear regression analysis showed that VTI(max), VTI(min) and ΔVTI were not significantly correlated with the duration of fasting (before PLR: r=0.111, 0.100, 0.047; after PLR: r=0.003, 0.033, 0.073, all P>0.05). Further multiple linear regression analysis indicated that, age and body weight were independent factors influencing IVC(RVI) and ΔVTI before and after PLR (IVC(RVI): β=-0.441, 0.515, -0.451, 0.507; ΔVTI: β=-0.442, 0.545, -2.422, 2.850; all P<0.05). However, the duration of fasting was not correlated with IVC(RVI) and ΔVTI after adjusting the age and weight (IVC(RVI): β=0.177, 0.160; ΔVTI: β=0.037, 0.054; all P>0.05). Conclusion: Age and weight, but not preoperative fasting duration, are correlated with respiratory variabilities of inferior vena cava diameter and aortic VTI in pediatric patients.

[Feasibility and perioperative safety of the combined procedure of catheter ablation and watchman left atrial appendage closure]

Objective: We aimed to explore the feasibility and perioperative safety of performing catheter ablation and left atrial appendage closure (LAAC) in a single (one-stop) session in patients with atrial fibrillation (AF). Methods: This study is an observational study. Consecutive AF patients who underwent the combined procedure of catheter ablation and LAAC with Watchman device of Xinhua Hospital in Shanghai between March 2017 and May 2019 were prospectively enrolled. Baseline, intra-and peri-procedural parameters were evaluated. Results: A total of 358 AF patients (189 males, (69.0±8.0) years) underwent the one-stop procedure. The CHA₂DS₂-VASc score was 3.2±1.5 and HAS-BLED score was 2.4±1.1, respectively in this patient cohort. Pulmonary vein isolation was achieved in all patients, while additional linear ablation was applied in 180 (50.3%) patients, yielding immediate success rate of 99.7%. Successful Watchman implantation was achieved in all patients. The perioperative serious adverse event occurred in 14 cases (3.9%). including 6 pericardial effusions (1.7%), 1 stroke (0.3%) and 5 vascular complications (1.4%), yielding procedure-related complication rate of 3.4%. In addition, 2 (0.6%) new-onset heart failures occurred postoperatively. There was no major bleeding or death during the perioperative period. Conclusions: Combined catheter ablation and LAAC can be successfully and safely performed in AF patients with high stroke risk. Follow-up data are needed to evaluate the outcome of this one-stop procedure.

[Survival analysis of people living with HIV/AIDS in Sichuan province, 1991-2017]

Objective: To analyze the survival time of people living with HIV/AIDS and related influencing factors in Sichuan province during 1991-2017. Methods: A retrospective cohort study was conducted to analyze the data of 143 988 HIV/AIDS cases. The data were collected from Chinese HIV/AIDS Comprehensive Information Management System. Life table method was used to calculate the survival proportion of the cases, and Cox proportion hazard regression model was used to identify the factors related with survival time. Results: Among 143 988 HIV/AIDS cases a total of 30 420 cases died of AIDS related diseases (21.1%) and the average survival time was 11.51 years (95%CI: 11.39-11.64). Multivariate Cox regression analysis showed that the influencing factors for the survival of HIV/AIDS cases were gender (male vs. female, HR=1.35, 95%CI: 1.32-1.40), education level (primary school or below vs. junior middle school: HR=1.15, 95%CI: 1.12-1.18), ethnic group (Han vs. other ethnic groups, HR=1.46, 95%CI: 1.41-1.52), occupation (farmer vs. other occupations: HR=1.26, 95%CI: 1.22-1.29), age (≥55 years old vs. 15-24 years old: HR=3.18, 95%CI: 3.02- 3.36), disease phase (AIDS vs. HIV infection: HR=1.44, 95%CI: 1.39-1.48), antiretroviral therapy (ART) (receiving ART vs. receiving no ART: HR=0.20, 95%CI: 0.19-0.20), and CD(4)(+)T cell counts at diagnosis (>500 cells/μl vs.<200 cells/μl: HR=0.42, 95%CI: 0.40-0.45). Conclusions: The average survival time of HIV/AIDS cases was 11.51 years in Sichuan during 1991- 2017. The risk factors for the survival of the cases were male, education level of primary school or below, Han ethnic group, farmer, old age at diagnosis, disease phase, The protective factors for the survival of HIV/AIDS cases were receiving ART and higher CD(4)(+) T cell counts at diagnosis.

[Clinical outcomes of peripheral blood stem cell transplantation for aggressive peripheral T-cell lymphoma]

目的

研究外周血造血干细胞移植治疗外周T细胞淋巴瘤（PTCL）的疗效。

方法

回顾性分析解放军总医院血液科2007年6月至2017年6月接受外周血造血干细胞移植PTCL患者的临床资料。

结果

共有41例PTCL患者纳入研究，男30例，女11例，中位年龄38（13~57）岁。17例行自体外周血造血干细胞移植（auto-PBSCT），24例行异基因外周血造血干细胞移植（allo-PBSCT）。auto-PBSCT组ALK阳性间变大细胞淋巴瘤占47.1%（8/17），allo-PBSCT组NK/T细胞淋巴瘤和外周T细胞淋巴瘤-非特指型占66.7%（16/24）。auto-PBSCT组患者移植前疾病处于完全缓解（CR）状态者占58.8%（10/17），疾病进展（PD）状态者占11.8%（2/17）；allo-PBSCT组移植前疾病状态为CR者8.3%（2/24），PD者45.8%（11/24）。auto-PBSCT组和allo-PBSCT组移植后2年总生存率、无病生存率差异均无统计学意义[（64.0±10.8）%对（53.5±9.7）%，P=0.543；（57.1±12.4）%对（53.5±10.6）%，P=0.701]。auto-PBSCT组6例死亡，5例死于复发；allo-PBSCT组12例死亡，其中5例死于复发，7例为移植相关死亡。

结论

auto-PBSCT和allo-PBSCT均是PTCL的有效治疗方法。

Morphological and molecular characterization of the muscle-infecting myxosporean Myxobolus xinyangensis sp. nov. from Abbottina rivularis in China

During an environmental assessment on the Huang River in Xinyang City (Henan Province, China), a novel Myxobolus species (Myxozoa: Myxobolidae) was found infecting the trunk muscle of Chinese false gudgeon Abbottina rivularis Basilewsky, 1855 (Gobioninae, Cyprinidae). Plasmodia of the new myxozoan, nominated herein as Myxobolus xinyangensis sp. nov., are round and yellowish, symmetrically and bilaterally located dorsal to the openings of the 2 opercula, and measure about 4.5 mm in diameter. The mature myxospores are orbicular in frontal view and fusiform in sutural view, with slightly tapered anterior end and rounded posterior end, and measure 9.4 ± 0.5 (8.7-10.6) µm long, 8.6 ± 0.6 (7.3-9.5) µm wide and 6.4 ± 0.3 (5.8-7.1) µm thick (mean ± SD, range). The ratio of spore length to spore width is close to 1. Two slightly unequal pyriform polar capsules, with tapering anterior ends and rounded posterior ends, measure 5.6 ± 0.67 (4.3-6.8) µm long and 3.0 ± 0.3 (2.4-3.6) µm wide, present as a figure 8 in the anterior part of spores and tightly converge at the top end of spores. Polar filament coils show 4 to 5 turns and are situated perpendicularly to the longitudinal axis of the polar capsules. No intercapsular appendix or sutural folds at the posterior end of spores were observed. The obtained partial small subunit ribosomal DNA sequence did not match any available data in GenBank and showed the highest sequence identity (93%) with 2 cyprinid trunk muscle-infecting Myxobolus species, M. pseudodispar and M. klamathellus. Phylogenetic analysis clearly showed that M. xinyangensis sp. nov. clustered within a cyprinid trunk muscle-infecting Myxobolus subclade at the basal position, but as an independent branch which was a possible reflection of its distinct myxospore morphology. This is the first record of infection of Myxobolus species in the trunk muscle of Abbotina fish.

Highly Anisotropic and Twofold Symmetric Superconducting Gap in Nematically Ordered FeSe_{0.93}S_{0.07}

FeSe exhibits a novel ground state in which superconductivity coexists with a nematic order in the absence of any long-range magnetic order. Here, we report on an angle-resolved photoemission study on the superconducting gap structure in the nematic state of FeSe_{0.93}S_{0.07}, without the complications caused by Fermi surface reconstruction induced by magnetic order. We find that the superconducting gap shows a pronounced twofold anisotropy around the elliptical hole pocket near Z (0, 0, π), with gap minima at the end points of its major axis, while no detectable gap is observed around Γ (0, 0, 0) and the zone corner (π, π, k_{z}). The large anisotropy and nodal gap distribution demonstrate the substantial effects of the nematicity on the superconductivity and thus put strong constraints on current theories.

Association of Beclin-1 and microRNA-30a expression with the severity and treatment response of colorectal cancer

We investigated the associations between Beclin-1 and microRNA-30a (miR-30a) expression and the severity and treatment response in colorectal cancer (CRC). Our sample size consisted of 139 CRC patients who were treated with surgery alone. Immunohistochemistry was used to investigate the expression and prognostic significance of Beclin-1 in CRC, while the weak expression of Beclin-1 in normal tissue was used as the basis for assessing tumors (control group). Real-time reverse transcription-polymerase chain reaction quantified miR-30a levels. The expression levels of Beclin-1 and miR-30a were associated with clinical variables and prognoses. Beclin-1 was expressed more highly in CRC tissues than in controls. This expression was related to gender (P = 0.023), histological grade (P = 0.006), M stage (P = 0.004), tumor node metastasis stage (P = 0.020), vascular invasion, and nodal involvement. Patients with higher Beclin-1 expression levels had higher survival rates (P = 0.08) than patients with lower Beclin-1 expression levels. Beclin-1 was a prognostic indicator (P < 0.05) in a multivariate analysis. Beclin-1 was overexpressed in CRC tissues and was correlated with lower levels of miR-30a (P < 0.05, r = -0. 4189). In conclusion, Beclin-1 was a good prognostic indicator in CRC and was correlated with survival rate. Beclin-1 is important in the growth and metastasis of CRC. Apoptosis in CRC might be due to the increased autophagy induced by decreased levels of miR-30a.

Transfusion-related acute lung injury in paediatric surgical patients: a retrospective study

BACKGROUND

Little is known about the occurrence of transfusion-related acute lung injury(TRALI) in Chinese paediatric patients. As such, a retrospective review of medical records from January 2008 to December 2011 was undertaken.

OBJECTIVE

To determine the incidence of TRALI and its risk factors in children (age <14 years).

STUDY DESIGN AND METHODS

All medical records of Sheng Jing Hospital from January 2008 to December 2011 were reviewed retrospectively using the hospital’s record system. Paediatric surgical patients who had been diagnosed clinically with acute lung injury were included. Transfusion data were collected, together with risk factors such as sepsis and aspiration.

RESULTS

In total, 1495 patients were involved in the study. Thirty-five cases were analysed further as they had acute lung injury, pulmonary oedema and respiratory distress. TRALI was confirmed in two of these cases. The average duration of transfusion was found to be significantly longer in patients with TRALI compared with controls, and the percentage of female donors was significantly higher for patients with TRALI.

CONCLUSION

The incidence of TRALI was found to be lower than reported previously, but TRALI is under-recognised, under-reported and undertreated.

Yeast CUP1 protects HeLa cells against copper-induced stress

As an essential trace element, copper can be toxic in mammalian cells when present in excess. Metallothioneins (MTs) are small, cysteine-rich proteins that avidly bind copper and thus play an important role in detoxification. YeastCUP1 is a member of the MT gene family. The aim of this study was to determine whether yeast CUP1 could bind copper effectively and protect cells against copper stress. In this study,CUP1 expression was determined by quantitative real-time PCR, and copper content was detected by inductively coupled plasma mass spectrometry. Production of intracellular reactive oxygen species (ROS) was evaluated using the 2',7'-dichlorofluorescein-diacetate (DCFH-DA) assay. Cellular viability was detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the cell cycle distribution of CUP1 was analyzed by fluorescence-activated cell sorting. The data indicated that overexpression of yeast CUP1 in HeLa cells played a protective role against copper-induced stress, leading to increased cellular viability (P<0.05) and decreased ROS production (P<0.05). It was also observed that overexpression of yeast CUP1 reduced the percentage of G1 cells and increased the percentage of S cells, which suggested that it contributed to cell viability. We found that overexpression of yeast CUP1 protected HeLa cells against copper stress. These results offer useful data to elucidate the mechanism of the MT gene on copper metabolism in mammalian cells.

Combination of IFNγ and chemotherapeutic agents increase TRAIL sensitivity of neuroblastoma cell lines

OBJECTIVE

Aim of the study was to further evaluate the role of caspase 8 and death receptors (DR) in the TRAIL-induced apoptosis of neuroblastoma (NB) cell lines.

METHODS

Caspase 8 mRNA expression was monitored by RT-PCR. Caspase 8, DR5 and DR4 protein expression were monitored by Western blot analysis. The effects of IFNγ, TRAIL, IFNγ+TRAIL, caspase 8 inhibitor+TRAIL and IFNγ+chemotherapeutic agents+TRAIL on the growth and apoptosis of NB cells were detected with MTT and flow cytometry. The relative caspase 8 activity was measured with colorimetric assay.

RESULTS

Caspase 8 expression was induced by IFNγ in the NB cell line SKNDZ. TRAIL alone did not induce apoptosis compared with controls but a combination of IFNγ+TRAIL and IFNγ+chemotherapeutic agents+TRAIL significantly induced cell apoptosis in SY5Y cells. Etoposide and doxorubicin induced DR5 but not DR4 in NB cell lines. SKNDZ cells expressing caspase 8 after treatment with IFNγ were still resistant to TRAIL but sensitive to TRAIL after the induction of DR5.

CONCLUSIONS

Sensitization of NB cells to TRAIL may be mediated by the upregulation of caspase 8 with IFNγ and DR5 with chemotherapeutic agents. This suggests that caspase 8 and death receptors play a very important role in TRAIL-induced apoptosis of NB cells and a combination of IFNγ, TRAIL and chemotherapeutic agents may be a new and interesting anticancer treatment strategy for NB.

The mutL Mutation in Pseudomonas aeruginosa Isolates Reveals Multidrug-resistant Traits and Possible Evolutionary Trends

To evaluate the genetic differences and possible evolutionary trends of clinical multidrug-resistant (MDR) strains, Pseudomonas aeruginosa isolates were characterized by pulsed-field gel electrophoresis (PFGE) and evolutionary distances were estimated. A total of 85.7% of the P. aeruginosa isolates were MDR strains. Strains with the PFGE pattern A predominated; all were susceptible to amikacin and cefepime but resistant to levofloxacin and meropenem (except strain PA45 which was sensitive to meropenem). PFGE pattern H or P strains exhibited resistance to six to eight different antibiotics. PFGE pattern I or J strains were susceptible to all antibiotics tested. Two imperfect six base-pair tandem repeats, CTGGCG and CTGGCC, were found in the mutL gene. In conclusion, MDR characteristics and PFGE profiles were clearly correlated with the mutL phylogenetic tree. This indicates that mutations in mutL might contribute to genetic stability in adaptation by changing the MDR traits. Phylogenetic analysis of mutL revealed the MDR relatedness of P. aeruginosa strains.

Hypertonic saline ameliorates cerebral edema through downregulation of aquaporin-4 expression in the astrocytes

Osmotherapy with 10% hypertonic saline (HS) alleviates cerebral edema through osmotic force. Aquaporin-4 (AQP4) has been reported to be implicated in the pathogenesis of cerebral edema resulting from a variety of brain injury. This study aimed to determine if 10% hypertonic saline ameliorates cerebral edema through downregulation of AQP4 expression in the perivascular astrocytes in the ischemic cerebral edema. Adult male Sprague-Dawley (SD) rats were subjected to permanent right-sided middle cerebral artery occlusion (MCAO) and treated with a continuous i.v. infusion of 10% HS. Brain water content (BWC) analyzed by wet-to-dry ratios in the ischemic hemisphere of SD rats was attenuated after 10% HS treatment. This was coupled with the reduction of neuronal apoptosis in the peri-ischemic brain tissue. Concomitantly, downregulated expression of AQP4 in the perivascular astrocytes after 10% HS treatment was observed. Our results suggest that in addition to its osmotic force, 10% HS exerts anti-edema effects possibly through downregulation of AQP4 expression in the perivascular astrocytes. The reduction of brain edema after 10% HS administration can prevent ischemic brain damage.

Molecular cloning of nuclear receptor coactivator-1 gene in pig

Nuclear receptor coactivator-1 (NCOA-1) as a member of Steroid receptor coactivator (SRC) family can interact with some DNA-bound nuclear receptors and enhance their transcriptional activation function, which is physiologically and pathologically important for animals and human. Much work has been done on the gene in human and mouse, but few in pig. Here we cloned and sequenced full length cDNA of NCOA-1 gene in pig. The putative protein includes 1440 amino acids. Sequences alignment showed that pig NCOA-1 gene cDNA sequence has identity of 93.73% with human and mouse, and putative pig NCOA-1 protein has identity of 94.99% with human, mouse and rat. The motifs, LXXLL, which have been demonstrated to be important for NCOA-1 mediating ligand-dependent and direct interaction with nuclear receptor, were conserved in pig.

Effects of two telephone survey methods on the level of reported risk behaviours

OBJECTIVE

Reporting bias due to social desirability is an important consideration in carrying out surveys on sensitive issues. The study compared the frequency of self reported sensitive behaviours and response rates between the conventional "telephone interviewer method" (TIM) and a combined interviewer and computerised data capturing method (telephone interviewer and computerised questionnaire method, or TICQM).

METHODS

A total of 580 males and 582 females were recruited and randomly assigned to either of the two methods in a cross sectional study. The overall response rate was about 51.6%.

RESULTS

While the two methods both had high completion and low item non-response rates, the TICQM respondents reported higher frequencies of sensitive risk behaviours. Sexually active female respondents interviewed by the TICQM were more likely to report that their sex partners were their steady boyfriend, instead of their husband; and were also more likely to admit that they had had "one night stand" experiences or had undergone an HIV antibody test, when compared with their counterparts in the TIM group. Similar contrasts were observed for sexually active male respondents, that the TICQM group were more likely to report that they had had sexual intercourse with female sex workers or non-regular sex partners. Sex differences in the strength of association were observed between some studied behaviours (for example, HIV testing and substance abuse) and modes of data collection.

CONCLUSION

The choice of data collection method has a significant impact on the results of sensitive studies; special attention should be given to designing the study and interpreting the results.

[Enantiomeric separations of 1-1,2,4-triazole compounds by micro-high performance liquid chromatography]

The enantiomeric separations of sixteen novel 1-1,2,4-triazole chiral compounds were investigated by micro-HPLC with a 200 mm x 100 microns i.d. capillary chiral OD column. The detection was performed at 223 nm. The mobile phase was a mixture of iso-propyl alcohol and n-hexane(20:80, V/V) at a flow rate of 30 microL/min and column head pressure of 6.9 MPa. Some of the enantiomers could be separated on baseline. In comparing with the separation results by the conventional HPLC method, the micro-HPLC method had the advantages of high-speed, economy, environmental friendliness etc. The effect of solute structure on enantio-selectivity was investigated and the chiral recognition mechanism was also discussed. It was found that the main separation mechanisms involve the pi-pi association and inclusion between the substituent R and the spiral pocket of OD-CSP.

A phospholipase C inhibitor, phenylmethylsulfonyl fluoride, ameliorates ischemic injury to brain mitochondria in rats

AIM

To study the effect of phenylmethylsulfonyl fluoride (PMSF), a phospholipase C inhibitor, on ischemic injury to brain mitochondria in rats.

METHODS

The phospholipid level, membrane fluidity, and respiratory control ratio of brain mitochondria were measured. The effect of phenylmethylsulfonyl fluoride was tested.

RESULTS

The phospholipid level, membrane fluidity, and respiratory control ratio of brain mitochondria in ischemia group decreased but increased in the PMSF treatment group (P < 0.05).

CONCLUSION

PMSF ameliorated ischemic injury to brain mitochondria in rats.

Transcription factor NF-kappaB participates in regulation of epithelial cell turnover in the colon

The transcription factor nuclear factor (NF)-kappaB regulates the expression of genes that can influence cell proliferation and death. Here we analyze the contribution of NF-kappaB to the regulation of epithelial cell turnover in the colon. Immunohistochemical, immunoblot, and DNA binding analyses indicate that NF-kappaB complexes change as colonocytes mature: p65-p50 complexes predominate in proliferating epithelial cells of the colon, whereas the p50-p50 dimer is prevalent in mature epithelial cells. NF-kappaB1 (p50) knockout mice were used to study the role of NF-kappaB in regulating epithelial cell turnover. Knockout animals lacked detectable NF-kappaB DNA binding activity in isolated epithelial cells and had significantly longer crypts with a more extensive proliferative zone than their wild-type counterparts (as determined by proliferating cell nuclear antigen staining and in vivo bromodeoxyuridine labeling). Gene expression profiling reveals that the NF-kappaB1 knockout mice express the potentially growth-enhancing tumor necrosis factor (TNF)-alpha and nerve growth factor-alpha genes at elevated levels, with in situ hybridization localizing some of the TNF-alpha expression to epithelial cells. TNF-alpha is NF-kappaB regulated, and its upregulation in NF-kappaB1 knockouts may result from an alleviation of p50-p50 repression. NF-kappaB complexes may therefore influence cell proliferation in the colon through their ability to selectively activate and/or repress gene expression.

Expression of transforming growth factor beta1 and its type II receptor in mouse colon tumors induced by azoxymethane

Alterations in transforming growth factor beta1 (TGF-beta1) and its type II receptor (TbetaR-II) have been implicated in the pathogenesis of a variety of human cancers and animal tumor models. We postulated that TGF-beta1 and TbetaR-II alterations may also be involved in mouse colon tumorigenesis induced by the chemical carcinogen, azoxymethane (AOM). In the present study, normal colon tissues and AOM-induced colon tumors from SWR/J mice were analyzed for mutational changes in the TbetaR-II gene, and the expression and localization of TGF-beta1 and TbetaR-II were examined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemisty. Direct DNA sequencing of the coding sequence of the TbetaR-II gene revealed no mutational changes in tumors induced by AOM when compared with the sequence from normal colon tissue. However, TGF-beta1 and TbetaR-II mRNA levels in tumor samples were increased 1.8-fold (p<0.01) and 1.3-fold (p<0.01), respectively, when compared with control mouse colon tissue. The results of immunohistochemical analysis of TGF-beta1 and TbetaR-II were correlated with mRNA expression data. An increase in staining intensity of both TGF-beta and TbetaR-II were observed in colon tumors. These findings suggest that alterations in the expression of TGF-beta1 and TbetaR-II may be involved in the pathogenesis of colon tumors induced by AOM in mice.

IkappaBbeta-related proteins in normal and transformed colonic epithelial cells

The transcription factor nuclear factor-kappaB (NF-kappaB) regulates genes that can influence cell proliferation, apoptosis, and inflammatory responses. Since these events can contribute to carcinogenesis, we examined the expression of NF-kappaB inhibitory proteins (IkappaBs) in normal and transformed colonic epithelial cells. Immunohistochemical analysis of the mouse colon revealed a high level of IkappaBbeta expression in epithelial cells relative to the rest of the tissue, whereas IkappaBalpha was found primarily in cells of the lamina propria. Mouse colon tumors showed a similar cell-specific staining pattern. Immunoblot analysis of IkappaBbeta from mouse colonocytes and the human HT-29 colon cancer cell line indicated that most of the IkappaBbeta in these cells was similar to the C-terminal-truncated IkappaBbeta2 isoform. Cell fractionation studies were consistent with IkappaBbeta being a major regulator of p65-p50 NF-kappaB complexes in HT-29 cells. Interestingly, two larger proteins specifically recognized by IkappaBbeta antibodies (p106 and p112) were found in HT-29 cells and in colon tissue of carcinogen-exposed mice. The p106 and p112 proteins bound to NF-kappaB, and their levels changed during the transient interleukin-1beta activation of NF-kappaB in HT-29 cells. Evidence was obtained indicating that p106 and p112 are stably ubiquitinated forms of IkappaBbeta. We propose that deficiencies in the proteasomal degradation of IkappaBbeta lead to p106 and p112 accumulation, which in turn alter NF-kappaB regulation in colon cancer cells.

Sequential and morphological analyses of aberrant crypt foci formation in mice of differing susceptibility to azoxymethane-induced colon carcinogenesis

Aberrant crypt foci (ACF), putative preneoplastic lesions, are early morphological changes induced by the colon carcinogen azoxymethane (AOM). Although inbred mice differ markedly in their susceptibility to AOM carcinogenesis, we have previously shown that ACF develop in both resistant and sensitive mouse strains after AOM treatment. The purpose of this study was to examine the sequential development and identify the morphological characteristics of ACF induced by AOM in the distal colon of sensitive and resistant mice. A/J (highly susceptible), SWR/J (relatively susceptible) and AKR/J (resistant) mice were treated with 10 mg/kg AOM or saline i.p. once a week for 6 weeks and were killed at 1, 2, 4, 6, 9 and 24 weeks after the last injection. The distal colons were stained with methylene blue and the numbers of ACF and tumors determined. Tumors were present as early as 4 weeks after AOM exposure in SWR/J and A/J mice and increased in frequency throughout the study in both strains. No tumors developed in the AKR/J mice. ACF, however, formed in all strains of mice. The greatest difference between susceptible and resistant strains was in the number of large ACF that developed at later time points. Furthermore, morphometric analysis revealed that A/J mice had the highest percentage of dysplastic ACF, followed by SWR/J mice. These data indicate that the difference in cancer risk from AOM may be due to the lack of progression of smaller ACF in the resistant mice and to the development of dysplasia in a higher percentage of ACF from susceptible strains.

Differential expression of p16(INK4a) in azoxymethane-induced mouse colon tumorigenesis

Alterations in the p16(INK4a) gene have been implicated in the pathogenesis of different human cancers and animal tumors. We postulated that alterations in the p16(INK4a) gene may also be involved in mouse colon tumorigenesis induced by the chemical carcinogen azoxymethane (AOM). In the present study, p16(INK4a) deletion status and its expression were examined in an AOM-induced mouse colon tumor model. Polymerase chain reaction-based deletion analysis of p16(INK4a) exon 2 showed no deletions in the colon tumors. The expression and localization of p16(INK4a) and its gene product were examined by reverse transcription-polymerase chain reaction and immunohistochemical analyses, respectively. The p16(INK4a) mRNA levels were low, and in some cases undetectable, in control colon tissue. However, colon tumors exhibited an eightfold increase in p16(INK4a) mRNA level when compared with control colon tissue (P < 0.01). Whereas control colon epithelium was uniformly negative for p16(INK4a) immunoreactivity, p16(INK4a)-immunoreactive cells were markedly increased in preneoplastic lesions and adenomas isolated from AOM-treated mice. To further examine the p16(INK4a) regulatory pathway, the retinoblastoma tumor-suppressor protein (Rb) was also examined immunohistochemically in these tissues. A heterogeneous Rb immunostaining was observed in preneoplastic lesions and adenomas. Immunohistochemical analysis also showed a reciprocal relationship between p16(INK4a) and Rb protein expression. These findings suggest that alterations in the p16(INK4a)/Rb pathway may play an important role in AOM-induced mouse colon tumorigenesis. Mol. Carcinog. 28:139-147, 2000.

Azoxymethane induces KI-ras activation in the tumor resistant AKR/J mouse colon

A differential susceptibility phenotype to the organotropic colon carcinogen azoxymethane (AOM) has been described in mice. The following studies were undertaken to test the hypothesis that intraspecific susceptibility can be accounted for by the specific complement of genetic alterations acquired by precancerous colon lesions referred to as aberrant crypt foci (ACF). As an initial approach to this question, mutations in codons 12 and 13 of the Ki-ras proto-oncogene were assessed in ACF, normal-appearing AOM-treated colonic epithelium, and tumors from A/J and SWR/J (susceptible) as well as AKR/J (resistant) mice. Four-week-old male mice were injected intraperitonealy, with AOM once a week for a total of 6 wk and killed 4 and 24 wk after the last injection. DNA was isolated from microdissected tissue, and polymerase chain reaction (PCR)-amplified products of Ki-ras exon 1 (codons 12 and 13) were directly sequenced from microdissected tissues. At 4 wk after AOM exposure, there was no significant difference in the frequency of Ki-ras activation (20-33%) between the three strains. Ki-ras mRNA expression was also evaluated by reverse transcription (RT)-PCR analysis and was comparably reduced (40-50%) in all three strains at the 4 wk time point. However, Ki-ras expression returned to normal by 24 wk after treatment. Finally, to gain further insight into the molecular pathogenesis underlying this experimental tumor model, analysis of the adenomatous polyposis coli (APC) protein within the colonic epithelium was undertaken by using an immunohistochemical approach. Although the APC protein was lost to a varying extent in tumors from A/J and SWR/J mice, the full-length form of the protein was still present in precancerous ACF isolated from each of the three strains, regardless of the degree of dysplasia of the lesion. A further molecular genetic analyses of ACF will be required to gain a more complete understanding of the molecular basis of tumor susceptibility phenotype in this murine model.

Expression analysis of the group IIA secretory phospholipase A(2) in mice with differential susceptibility to azoxymethane-induced colon tumorigenesis

The murine non-pancreatic secretory phospholipase A(2) (sPLA(2)) has been proposed as a tumor modifier of multiple intestinal neoplasia (Min). A genetic polymorphism in the mouse gene that causes a disruption in exon 3 results in loss of functional protein. Mouse strains with a disrupted sPLA(2) gene are susceptible to the Min phenotype and develop numerous intestinal polyps, whereas mice with normal sPLA(2) develop only a limited number of polyps. The following study was undertaken to test the hypothesis that sPLA(2) plays an equivalent role in murine susceptibility to the colon carcinogen azoxymethane (AOM). sPLA(2) status was confirmed by sequencing in mice that are highly susceptible (A/J), susceptible (SWR/J) and resistant (AKR/J) to AOM-induced tumorigenesis. Constitutive expression of sPLA(2) mRNA was compared in small intestine and colon of untreated mice using semi-quantitative RT-PCR. Whereas mRNA expression was nearly absent in A/J mice, AKR/J mice exhibited extensive expression throughout the intestine. Despite the wild-type sPLA(2) gene, colonic mRNA expression in SWR/J mice was significantly lower relative to AKR/J. Immunohistochemical analysis of sPLA(2) protein confirmed the mRNA data. The effect of AOM on colonic sPLA(2) expression was also examined. Twenty-four weeks after the last of six weekly injections of AOM (10 mg/kg i.p.), RT-PCR analysis of distal colons revealed a significant increase in mRNA in normal-appearing epithelium and tumor tissue from AOM-treated mice relative to controls. However, there was no corresponding increase in protein expression in A/J mice. The absence of sPLA(2) expression within control colons of tumor-susceptible A/J mice together with low expression in SWR/J colons is consistent with its potential role as an intestinal tumor modifier, but the carcinogen-induced increase in expression raises doubts as to the significance of sPLA(2) in inhibiting carcinogenesis.

[beta-Cyclodextrin bonded stationary phases for chiral separation in HPLC]

A review of beta-cyclodextrin bonded stationary phases in chiral liquid chromatography is given, focusing on design and synthesis of beta-cyclodextrin bonded chiral stationary phases. Fifty-three references are presented in this paper.

Preliminary analysis of azoxymethane-induced colon tumorigenesis in mouse aggregation chimeras

Inbred mice exhibit differential susceptibility to colon carcinogens. The following study addresses the possibility that differences are intrinsic to colonic mucosa (cell autonomous) or are mediated by extracolonic systemic factors (e.g. liver activation of carcinogens). Our approach was to construct mouse aggregation chimeras, mice whose tissues are a mosaic of cells derived from two parental genotypes, from a susceptible (SWR) and a resistant (DBA/2) strain. Forty-five embryo aggregations yielded 11 viable pups, four of which were chimeric by coat color. Six-week-old SWR<-->BA/2 chimeras were injected i.p. with azoxymethane (AOM) once a week for 8 weeks (5 and 7.5 mg/kg body wt for 2 weeks followed by 10 mg/kg for 6 weeks) and tumor incidence in distal colon was evaluated 15 weeks after the last injection. Additional groups of parental mice received the same treatment. In the parental SWR treatment group, 1.7 +/- 0.82 tumors/colon were found. No tumors were observed in AOM-treated DBA/2 mice. In SWR<-->DBA/2 chimeras exposed to AOM, 2.8 +/- 2.1 tumors/colon were found. Tumor lineage was examined in paraffin sections stained with Dolichos biflorus agglutinin-peroxidase, a cell surface specific marker that stains intestinal endothelial cells of SWR and epithelial cells of DBA/2. Cellular lineage of tumors was further evaluated by microsatellite analysis of DNA isolated by microdissection. There was no significant difference in tumor incidence between SWR parental and chimera treatment groups. Histochemical analysis of tumor tissue in chimeras suggested that most tumors were derived from SWR. However, subsequent genetic analysis of tumors indicated mixed parental composition. These preliminary studies suggest that DBA/2 resistance mechanisms are not sufficient to protect adjacent SWR-derived epithelium from the tumorigenic effects of AOM.

Lipophilicity determination of some potential photosystem II inhibitors on reversed-phase high-performance thin-layer chromatography

The retention characteristics of 25 2-cyano-3-methylthio-3-substituted amine-acrylates are determined using reversed-phase thin-layer chromatography (RP-TLC) with methanol-water mixtures as eluents. The relationship between Rm values and partition coefficients (C log P) are established. The Rm values decrease linearly with increasing methanol concentration in the eluent. The Rm values extrapolated to zero organic modifier concentration (Rm0) in the eluent are highly related to C log P. The Rm0 value can be used to evaluate the lipophilicity of this kind of compound.

Quantitative assessment of azoxymethane-induced aberrant crypt foci in inbred mice

Heritable differences in tumor susceptibility are observed in mice after repetitive exposures to the organotropic colon carcinogen azoxymethane (AOM). The following study was undertaken to determine whether early morphological alterations within the colonic epithelium correlate with subsequent cancer risk. A/J and SWR/J (susceptible) and AKR/J (resistant) mice were injected once a week with AOM at a dose of 10 mg/kg, i.p., for a total of 6 weeks. Four weeks after the last injection, methylene blue-stained whole-mount colons were examined for the presence of colonic epithelial lesions referred to as aberrant crypt foci (ACF). Putative lesions identified under low magnification were further characterized by H&E staining of corresponding sections. AOM produced a treatment-related increase in ACFs in each of the mouse lines examined. The tumor-susceptible SWR/J and A/J mice developed on average between three- and sixfold more ACFs in the distal colon (32 and 15/cm of colon, respectively) than the resistant AKR/J mice (5/cm colon). The size distribution of ACFs was further analyzed in each of the strains. In SWR/J and A/J, 20-35% of lesions were classified as large ACFs, consisting of 5 or more aberrant crypts per focus. This is in striking contrast to the size distribution of lesions identified in the AKR/J colons, where fewer than 5% of grossly identified lesions were classified as large. In fact, the majority (> 80%) of ACFs in AKR/J mice consisted of only 1-2 aberrant crypts@focus. In addition, there was no evidence of dysplasia in any of the AKR/J lesions examined, whereas the lesions in susceptible mice were dysplastic (adenomas). Our data indicate that tumorigenic response is associated with the extent and multiplicity of ACFs that form within the colonic epithelium at an early time point after carcinogen exposure. These studies further support the use of this morphological biomarker as a short-term endpoint of colon tumorigenesis.

Altered expression of cyclin D1 and cyclin-dependent kinase 4 in azoxymethane-induced mouse colon tumorigenesis

Alterations in the expression of the cell cycle regulators, cyclin D1 and cyclin-dependent kinase 4 (Cdk4), have been implicated in malignancies of both humans and experimental animal models. We hypothesize that altered expression of cyclin D1 and Cdk4 may also be involved in mouse colon tumorigenesis induced by the chemical carcinogen, azoxymethane (AOM). In the present study, SWR/J mice were given AOM by i.p. injection at a dose of 10 mg/kg once a week for 8 weeks, and colonic tissue and tumors were isolated 18 weeks later. The expression and localization of cyclin D1 and Cdk4 were examined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical analyses. Cyclin D1 and Cdk4 mRNA levels in tumor samples were increased 1.3-fold (P < 0.01) and 1.2-fold (P < 0.01), respectively, when compared with control mouse colon tissue. Control colon epithelium was uniformly negative for cyclin D1 immunoreactivity, whereas minimal Cdk4 nuclear staining was confined to the lower portion of the crypts within the control tissue. Both cyclin D1 and Cdk4 immunoreactive cells were markedly increased in preneoplastic lesions and in adenomas isolated from AOM-treated mice. Furthermore, some morphologically normal colon crypts from AOM-treated mice showed positive cyclin D1 immunoreactivity. These findings suggest that overexpression of cyclin D1 and Cdk4 occurs early in the AOM-induced mouse colon tumorigenesis and may contribute to tumor progression in this model.

Azoxymethane-induced colon tumors and aberrant crypt foci in mice of different genetic susceptibility

Azoxymethane (AOM) is an organotropic colon carcinogen that is commonly used to induce colon tumors in rodents. Unlike its parent compound, 1,2-dimethylhydrazine (DMH), a tumor susceptibility phenotype in inbred mice with respect to AOM has not been established. Thus, this study was undertaken to determine whether genetic susceptibility extends to this carcinogen. SWR/J, A/J (both susceptible to DMH carcinogenesis) and AKR/J (resistant) mice were treated with 10 mg/kg AOM i.p. once a week for 8 weeks. Twenty-five weeks after the initial injection, tumor yield was determined. With a single exception, only SWR/J and A/J mice developed tumors, with a distribution that was limited to the distal colon (16.3+/-1.1 and 36.4+/-2.4. respectively). The formation of aberrant crypt foci (ACF), putative preneoplastic lesions, was also assessed in whole-mount colons using Methylene Blue staining. Consistent with tumor multiplicity, the total number of ACF was highest in A/J mice, followed by SWR/J mice. In addition, A/J mice had a significantly greater number of large ACF (five or more crypts per foci) than the other strains. Despite the absence of colon tumors, however, AKR/J mice did develop a significant number of ACF. This finding suggests that ACF in resistant mice are persistent but do not progress to tumors.

Expression of cell cycle proteins in 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced mouse lung tumors

Cyclin D1 dysregulation and differential inactivation of p16INK4a and Rb have been observed in human lung cancer. In chemically induced mouse lung tumors, the p16INK4a gene is a target of inactivation, and Rb is reduced at the mRNA level (Northern blot) although similar at the protein level (Western blot) when compared to normal lung tissues. The expression of cyclin D1, cdk4, p16INK4a, and Rb protein was examined by immunohistochemistry in 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced mouse lung tumors. Immunohistochemical staining revealed exclusive nuclear staining of both cyclin D1 and cdk4 that was light to moderate in normal mouse lung tissues, but intense in lung adenomas and adenocarcinomas. Western blot analysis confirmed the increased expression of cyclin D1 and cdk4 in lung tumors compared to normal lung. Immunohistochemical analyses of lung tumors showed focal areas which lacked p16INK4a staining. Expression of p16INK4a, as determined by RT-PCR, was variable in lung tumors. Mutations in p16INK4a were not found by SSCP analysis. Immunohistochemical analyses of normal lung tissues showed intense staining for Rb protein in alveolar epithelial cells and in other lung cell types; however, in the lung tumors the staining intensity was reduced and the distribution was altered. Expression of Rb was detected in normal lung tissues but was barely detectable by Northern blot hybridization in lung tumors. Western blot analysis indicated the presence of both hypophosphorylated and hyperphosphorylated Rb protein in lung tumors and in normal lung tissues. These results suggest that alterations in the cell cycle proteins, cyclin D1, cdk4, p16INK4a, and Rb, may play a role in the acquisition of autonomous growth by adenomas. Furthermore, they demonstrate the importance of immunohistochemical studies to examine expression in tissues that contain multiple cell types, such as the lung, and in tumors that by nature are heterogeneous.

p53-independent down-regulation of cyclin D1 and p21Waf1 in the process of immortalization of human esophageal epithelial cells

Immortalization is considered to be an initial critical step in the process of multistage cell transformation. However, the molecular mechanisms underlying this event are not well understood. Our laboratory previously established the immortalized human esophageal epithelial cell line, HET-1A, by SV40 T-antigen transfection. In the present study, we investigated the role of G1 cyclins and cyclin dependent kinase inhibitors, in the process of immortalization. By using immunoprecipitation and Western blot analysis, sequential changes in the expression of both cyclin D1 and p21Waf1 were detected during the conversion of precrisis esophageal epithelial cells to immortalized HET-1A cells. Reduced expression levels of both cyclin D1 and p21Waf1 were found in early passage and late passage immortalized cells when compared to levels in precrisis cells. In addition, continued subculture of the immortalized cells led to increased expression levels of both cyclin D1 and p21Waf1. No significant changes in the expression of either cyclin E or p53 were observed in early or late passage immortalized cells when compared to precrisis cells. These results suggest that changes in the expression levels of cyclin D1 and p21Waf1, but not cyclin E, may be important for immortalization and continued propagation of human esophageal epithelial cells, and these changes are not dependent on regulation by p53.

[An approach to use cancer registration to assess cancer risks by occupation and industry]

This study explored how to use cancer registration data to assess cancer risk. Based on the data of the Tianjin Cancer Registry, the occupational and industrial risk for lung cancer were assessed as examples. All cases of cancer aged at least 20 years and reported during 1981-1987 to the TCR formed the basis of the study. A comparison was made using case-case methodology that cases of one cancer site compared with cases of all other sites. Data were re-coded according to 30 occupational and 27 industrial categories. The individuals employed in the interested category were considered as exposed, and subjects employed in all other categories were considered as unexposed. Statistical analysis was conducted by unconditional multiple logistic regression. Regression models included sex, age and year of diagnosis. From our study, the results are constant with previous reports. The systematic analysis of the association between occupation and industry of employment and cancer among men and women registered in the TCR provided confirmation in this population of a number of known or suspected occupational cancer risk factors studied in industrialized countries. The main advantages of this design are 1. To use the data of a cancer registration that are already existed. 2. It is easy, fast and less cost to screening the cancer risk or potential cancer risk. 3. All factors in the database of cancer registration could be evaluated, for example, occupation, industry, education, etc. 4. The way to define cases and exposed groups could decrease the influence of confounding and bias.

[Clinical and experimental study on treatment of chronic hepatitis B with yanggan aoping mixture]

OBJECTIVE

To assess the efficacy of Yanggan Aoping Mixture (YGAPM) in treating hepatitis B.

METHODS

Patients suffered from chronic hepatitis B were treated with YGAPM. Observe their short- and long-term efficacy and the change of serum hepatitis B virus marker. In experiment, the effect of YGAPM in treating rat's liver injury as well as HBV-infected tree shrew and duck HBV-infected ducks was observed.

RESULTS

In 79 cases of chronic persistant hepatitis, the markedly effective rate was 60.76%, and follow-up studies on 40 cases, the further rasied to 70.00%. In 73 cases of chronic active hepatitis, the markedly effective rate was 60.27%, and further raised to 62.50% in 32 follow-up cases. In the treatment group, 85 (71.43%) of the 119 cases with HBeAg-positive turned to negative. Whereas in the control group, only 40 (44.94%) of 89 HBeAg-positive cases turned to negative, P < 0.01. Results of experimental study showed that negative conversion rate of tree shrew infected with HBV marker was raised, while infected duck blood with duck HBV DNA was inhibited. Those compared with the control group separately, the difference was remarkably significant.

CONCLUSIONS

YGAPM is an effective drug in treating chronic hepatitis B, and it could effectively negative convert the HBV marker.

Overexpression of cyclin D1 and cyclin E in N-nitrosomethylbenzylamine-induced rat esophageal tumorigenesis

Dysregulation of G1 cyclins has been implicated in several human malignancies. To further investigate the role of G1 cyclins in chemical carcinogenesis, the expression of cyclin D1 and cyclin E was analyzed by RT-PCR and immunohistochemical studies in N-nitrosomethylbenzylamine (NMBA)-induced rat esophageal tumorigenesis. Cyclin D1 mRNA levels were increased 2.8-fold in 25 week (P < 0.05) and 6.8-fold in 45 week (P < 0.01) papillomas induced by NMBA, when compared with normal rat esophageal epithelium. Cyclin E mRNA levels were increased 6.2-fold in 25 week (P < 0.01) and 6.9-fold in 45 week (P < 0.01) papillomas. Immunohistochemical staining revealed exclusive nuclear staining of both cyclin D1 and cyclin E. Furthermore, there was a sequential increase in cyclin D1- and cyclin E-positive cells from normal epithelium, to preneoplastic lesions, to papillomas. These findings suggest that overexpression of cyclin D1 and cyclin E occur relatively early in rat esophageal tumorigenesis and participate in tumor progression in this model.

Alterations in transforming growth factor-alpha and epidermal growth factor receptor expression during rat esophageal tumorigenesis

Transforming growth factor-alpha (TGF-alpha) stimulates cell proliferation through interaction with its receptor, the epidermal growth factor receptor (EGFR), by activating its tyrosine kinase activities. The simultaneous overexpression of TGF-alpha and EGFR by tumor cells is thought to trigger the autocrine growth pathway, leading to uncontrolled proliferation. To examine their roles in rat esophageal tumorigenesis induced by the chemical carcinogen N-nitrosomethylbenzylamine (NMBA), TGF-alpha, and EGFR expression was evaluated in normal rat esophageal epithelium, in NMBA-induced preneoplastic lesions, and in papillomas by quantitative reverse transcription-polymerase chain reaction (RT-PCR), in situ hybridization, and immunohistochemical analyses. Compared with the levels in normal epithelium, the TGF-alpha and EGFR mRNA levels in esophageal papillomas were 3.6 and 1.9 times higher, respectively. In the preneoplastic epithelium, although a trend of increased TGF-alpha and EGFR mRNA levels was observed, collectively there were no significant differences between preneoplastic and normal samples by RT-PCR analysis. In situ hybridization and immunohistochemical staining showed increased levels of TGF-alpha and EGFR mRNA and protein products in papillomas and in pronounced hyperplastic and dysplastic lesions. TGF-alpha and EGFR expression correlated with each other and with the expression of proliferating cell nuclear antigen, a marker for cell proliferation. These results suggest that disregulation of TGF-alpha and EGFR expression may contribute to autonomous cell growth and may play an important role in rat esophageal tumorigenesis induced by NMBA.

Occupational risk factors for lung cancer in Tianjin, China

Information about occupation and industry of cancer patients is routinely recorded in the Cancer Registry of Tianjin, People's Republic of China. Occupational risk factors of lung cancer for the period of 1981-1987 were assessed using other cancers as controls. For each occupation and industry, workers employed in it were considered exposed and were compared with all other workers. Elevated risks were found for a number of industries for both sexes, including, in particular, the textile, wood, metal, and construction industries. Results by occupation were similar to those by industry. Smoking scores were calculated for various occupations on the basis of a separate population survey in Tianjin. Smoking cannot explain the elevated odds ratios in males, while among females a strong correlation was observed between smoking scores and lung cancer odds ratios, suggesting a confounding effect.

Diet and breast cancer in Shanghai and Tianjin, China

Various aspects of adult diet have been linked to breast cancer development. These include intake of fat (risk factor), and intake of fibre, soy protein and vitamins A, C and E (protective factors). Results of previous studies have been inconsistent. We examined the possible associations between breast cancer and various indices of nutrient and food intake in two Chinese populations who are at relatively low risk for breast cancer (one-fifth the rate in US white women). Two case-control studies of breast cancer were conducted in the cities of Shanghai and Tianjin, China. In Shanghai, 534 women aged 20-69 years with histologically confirmed breast cancer were recruited, whereas in Tianjin 300 women aged 20-55 years with histologically confirmed breast cancer were interviewed. All controls were community controls who were individually matched to the cases by sex and age (case-control ratio = 1:1). All interviews were conducted in person. Findings from the two studies were similar, although the diets in Shanghai and Tianjin were different in many respects. Cases and controls were similar in their consumption of soy protein, measured either in absolute levels or as percentages of total protein. Overall, all components of dietary fat (saturated fat, monounsaturated fat, polyunsaturated fat) showed a modest, non-significant association with breast cancer after adjustment for energy intake and other non-dietary risk factors for breast cancer. Intake of crude fibre, carotene and vitamin C, on the other hand, exhibited strong, statistically significant inverse associations with breast cancer risk. The last three indices were highly correlated, rendering it impossible to disentangle their individual effects; they were closely associated with intake of green vegetables in the two study populations. Vitamin E intake was unrelated to breast cancer risk in Shanghai and Tianjin. In the multivariate logistic regression model which included all non-dietary risk factors for breast cancer and energy intake, Shanghai women in the lowest tertile of crude fibre intake and highest tertile of fat intake had a 2.9-fold increased risk for breast cancer relative to those in the highest tertile of crude fibre intake and lowest tertile of fat intake. The comparable relative risk in Tianjin women was 2.4. Our data indicate a strong protective effect against breast cancer development with intake of foods rich in fibre, vitamin C and carotene. Our results are also compatible with dietary fat having a modest, positive effect on breast cancer risk within the range of exposure experienced by women in China.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of indocyanine green retention and aminopyrine breath tests in patients with malignant biliary obstruction

Impaired hepatic function is a major contributory factor to the high incidence of postoperative morbidity and mortality in patients with malignant biliary obstruction. Dynamic hepatic function tests such as indocyanine green (ICG) retention and aminopyrine breath tests were evaluated in such patients to define whether they were clinically useful for prediction of postoperative morbidity and mortality. Forty-four patients with malignant biliary obstruction undergoing surgery for relief of obstructive jaundice were recruited into the study. Indocyanine green retention and aminopyrine breath tests were carried out in all patients pre-operatively and repeated in 36 patients postoperatively. The ICG retention was abnormal in all patients before surgery and there was significant improvement 2 weeks after surgery (32.8 +/- 2.5% vs 18.3 +/- 2.8%, P = 0.001). The change in ICG retention levels correlated with the serum bilirubin levels but the pre-operative ICG retention value could not predict postoperative morbidity and mortality. The aminopyrine breath test was abnormal in all but one patient. It correlated with pre-operative prothrombin time of the patients before surgery but it did not improve significantly after surgery and was not predictive of postoperative outcome. It is concluded that both ICG retention and aminopyrine breath tests have limited clinical value in the pre-operative evaluation of patients with malignant biliary obstruction.

Hepatitis C virus genotypes in France: comparison of clinical features of patients infected with HCV type I and type II

Two major hepatitis C virus genotypes, F1 and F2, corresponding to hepatitis C virus type I and type II respectively, were found in France. To investigate the correlation between infection with these genotypes (F1 and F2) and clinical features of patients, serum samples proven to be hepatitis C virus positive by polymerase chain reaction amplification on 5' non-coding region were further amplified in the NS3 region with nested polymerase chain reaction. The NS3-polymerase chain reaction products were Southern blotted and hybridized with specific probes to identify the genotype of hepatitis C virus. Of 70 samples 64 were NS3-polymerase chain reaction positive. Twenty-eight (40%) samples were hepatitis C virus type I (F1) and 34 (49%) were hepatitis C virus type II (F2), while one sample (HB) hybridized with both probes and another (HN) hybridized with neither. Some samples were sequenced, with results consistent with those of hybridization. The HB sample was related more to hepatitis C virus type II than to type I and the HN sample was divergent from both type I and type II genotypes. Clinical profiles of patients infected with hepatitis C virus type I and type II were compared. Type I infected patients were younger (p < 0.01) and more often male (p < 0.05) than those of the type II group. Nine of 28 patients in the type I infected group had a history of drug abuse, whereas none did in the type II group. Five of 22 (23%) type I infected patients and 19 of 32 (59%) type II infected patients had cirrhosis (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Cancer mortality in Chinese immigrants to New York City. Comparison with Chinese in Tianjin and with United States-born whites

BACKGROUND

Cancer rates in immigrant populations are frequently found to be intermediate between the country of origin and the adopted country. Such observations play an important role in establishing the environmental origin of cancer. Chinese now constitute the third largest group immigrating to New York City.

METHODS

Cancer deaths in New York City (1986-90) among 706 male and 412 female foreign-born Chinese were compared using proportional cancer mortality ratios (PCMR) with Chinese who died of cancer in Tianjin, China (19,461 deaths, 1983-87), and with United States-born whites in New York City (32,293 deaths).

RESULTS

Cancer sites were divided into those for which the age-adjusted PCMR were significantly higher in Tianjin Chinese (TC) compared with New York City whites (NYW), and those for which PCMR were significantly lower in TC compared with NYW. PCMR for Chinese immigrants usually fell between those of TC and NYW, but some were closer to those of TC (e.g., liver, gallbladder, female lung) whereas other sites were closer to those of NYW (e.g., esophagus, colon, rectum).

CONCLUSIONS

These data provide additional support for the concept that much cancer originates with and can be modified by environmental factors.

[A case control study on risk factors of endometrial carcinoma in Tianjin]

A case-control study was conducted on risk factors of endometrial carcinoma in Tianjin. The data was analysed with chi 2 test an linear logistic regression. The risk factors of endometrial carcinoma including age of marriage, menopause, body mass index, exposure to X-ray, hypertension, pregnancies, and lactation were investigated. The results showed that body mass index, and exposure to X-ray were predominant risk factors; while pregnancies and lactation were protective factors.