[Co-exposure of carbon black and cadmium induces autophagy and inflammation in human bronchial epithelial cells via PERK pathway]

Objective: To investigate the effects of carbon black and cadmium (Cd) combined exposure on autophagy and inflammatory response mediated by protein kinase R-like endoplasmic reticulum kinase (PERK) pathway in human bronchial epithelial (16HBE) cells. Methods: In January 2022, human bronchial epithelial (16HBE) cells were resuscitated and cultured. Carbon black nanoparticles (CBNPs) were oxidized to adsorb Cd ions to construct "CBNPs-Cd" complexes. CCK-8 assay was used to detect the effects of different concentrations and time combinations of CBNPs and Cd on the viability of 16HBE cells. The subsequent dose groups were exposed to 2 μg/ml Cd, 100 μg/ml CBNPs, 100 μg/ml CBNPs+2 μg/ml Cd for 24 h. The number of autophagosomes and autolysosomes was detected by transmission electron microscopy. Western blotting was used to detect the protein expressions of PERK, eukaryotic initiation factor 2α (eIf2α), activating transcription factor 4 (ATF4), sequestosome 1 (SQSTM1/P62), and microtubule-associated protein 1 light chain 3 (LC3). After PERK gene was silenced by siRNA technology, the changes of autophagy marker proteins P62 and LC3 were detected, and the expressions of inflammatory factors interleukin-6 (IL6) and interleukin-8 (IL8) were detected by fluorescence quantitative PCR technique. One-way ANOVA analysis was used to compare three groups or more. LSD test was used for comparison between two groups. Factorial analysis was used for multivariate component analysis. Results: There was no significant change in cell viability of 16HBE after 24 h exposure to CBNPs and Cd alone or combined (P>0.05). Compared with the control group, the expressions of P62 and LC3 in 16HBE cells were significantly increased in the CBNPs and Cd alone/combined exposure group (P<0.05), and the number of autophagosomes and autophagolysosomes in the combined exposure group was increased compared with other groups. Compared with the control group, CBNPs and Cd alone exposure group had no significant effects on p-PERK/PERK and p-eIf2α/eIf2α protein expression (P>0.05). However, the protein expressions of p-PERK/PERK and p-eIf2α/eIf2α and ATF4 were all increased in the combined exposure group (P<0.05), and the levels of IL6 and IL8 in 16HBE cells in the combined exposure group of CBNPs and Cd were significantly higher than those in the control group (P<0.05). The levels of LC3 protein, IL6 and IL8 were decreased in the CBNPs-Cd combined exposure group after knockdown of PERK gene (P<0.05). The results of factorial analysis showed that exposure to CBNPs and Cd had significant effects on the expression of P62, LC3 and IL6 (P<0.05), but the interaction between the two chemicals had no statistical significance (P>0.05) . Conclusion: CBNPs-Cd combined exposure may inhibit autophagy and increase inflammation in human bronchial epithelial cells through activation of PERK-eIf2α-ATF4 pathway.

[Effects of enhancing the expression of aryl hydrocarbon receptor in post-traumatic mice macrophages on the inflammatory cytokine level and bactericidal ability]

Objective: To explore the expression pattern of aryl hydrocarbon receptor (AhR) in mice peritoneal macrophages (PMs) after major trauma and analyze the effects of enhanced AhR expression on the inflammatory cytokine level and bactericidal ability after trauma. Methods: The experimental study method was used. Forty 6-8-week-old male C57BL/6J mice (the same mouse age, sex, and strain below) were divided into control group, post trauma hour (PTH) 2 group, PTH 6 group, and PTH 12 group according to the random number table (the same grouping method below), with 10 mice in each group. Mice in the latter 3 groups were constructed as severe trauma model with fracture+blood loss, while mice in control group were left untreated. The primary PMs (the same cells below) were extracted from the mice in control group, PTH 2 group, PTH 6 group, and PTH 12 group when uninjured or at PTH 2, 6, and 12, respectively. Then the protein and mRNA expressions of AhR were detected by Western blotting and real-time fluorescence quantitative reverse transcription polymerase chain reaction, respectively, and the gene expressions of AhR signaling pathway related molecules were analyzed by transcriptome sequencing. Twenty mice were divided into control group and PTH 6 group, with 10 mice in each group, and the PMs were extracted. The level of ubiquitin of AhR was detected by immunoprecipitation. Twelve mice were divided into dimethyl sulfoxide (DMSO) alone group, PTH 6+DMSO group, MG-132 alone group, and PTH 6+MG-132 group, with 3 mice in each group. After the corresponding treatment, PMs were extracted, and the protein expression of AhR was detected by Western blotting. Twenty mice were constructed as PTH 6 model. Then, the PMs were extracted and divided into empty negative control adenovirus (Ad-NC) group and AhR overexpression adenovirus (Ad-AhR) group. The protein expression of AhR was detected by Western blotting at 36 h after some PMs were transfected with the corresponding adenovirus. The rest cells in Ad-NC group were divided into Ad-NC alone group and Ad-NC+endotoxin/lipopolysaccharide (LPS) group, and the rest cells in Ad-AhR group were divided into Ad-AhR alone group and Ad-AhR+LPS group. The expressions of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) in the cell supernatant were detected by enzyme-linked immunosorbent assay at 12 h after the corresponding treatment (n=6). Twenty mice were obtained to extract PMs. The cells were divided into control+Ad-NC group, PTH 6+Ad-NC group, control+Ad-AhR group, and PTH 6+Ad-AhR group, and the intracellular bacterial load was detected by plate spread method after the corresponding treatment (n=6). Data were statistically analyzed with one-way analysis of variance, least significant difference test, analysis of variance for factorial design, and independent sample t test. Results: Compared with 1.16±0.28 of control group, the protein expressions of AhR in PMs in PTH 2 group (0.59±0.14), PTH 6 group (0.72±0.16), and PTH 12 group (0.71±0.17) were all significantly decreased (P<0.05). The overall comparison of the difference of AhR mRNA expression in PMs among control group, PTH 2 group, PTH 6 group, and PTH 12 group showed no statistical significance (P>0.05). The AhR signaling pathway related molecules included AhR, AhR inhibitor, cytochrome P450 family member 1b1, cytochrome P450 family member 11a1, heat shock protein 90, aryl hydrocarbon receptor-interaction protein, and heat shock protein 70 interaction protein. The heat shock protein 90 expression of PMs in PTH 2 group was higher than that in control group, while the expressions of other molecules did not change significantly after trauma. Compared with that in control group, the level of ubiquitin of AhR in PMs in PTH 6 group was increased. Compared with that in DMSO alone group, the protein expression of AhR in PMs in PTH 6+DMSO group was decreased, while that in PMs in MG-132 alone group had no significant change. Compared with that in PTH 6+DMSO group, the protein expression of AhR in PMs in PTH 6+MG-132 group was up-regulated. At transfection hour 36, compared with that in Ad-NC group, the protein expression of AhR in PMs in Ad-AhR group was increased. At treatment hour 12, compared with those in Ad-NC+LPS group, the expressions of IL-6 and TNF-α in PM supernatant of Ad-AhR+LPS group were significantly decreased (with t values of 4.80 and 3.82, respectively, P<0.05). The number of intracellular bacteria of 1×106 PMs in control+Ad-NC group, PTH 6+Ad-NC group, control+Ad-AhR group, and PTH 6+Ad-AhR group was (3.0±1.8), (41.8±10.2), (1.8±1.2), and (24.2±6.3) colony forming unit, respectively. Compared with that in PTH 6+Ad-NC group, the number of intracellular bacteria of PMs in PTH 6+Ad-AhR group was significantly decreased (t=3.61, P<0.05). Conclusions: Ubiquitin degradation of AhR in PMs of mice after major trauma results in decreased protein expression of AhR. Increasing the expression of AhR in post-traumatic macrophages can reduce the expressions of LPS-induced inflammatory cytokines IL-6 and TNF-α, and improve the bactericidal ability of macrophages after trauma.

Helichrysetin inhibits gastric cancer growth by targeting c-Myc/PDHK1 axis-mediated energy metabolism reprogramming

Helichrysetin (HEL), a chalcone isolated from Alpinia katsumadai Hayata, has an antitumor activity in human lung and cervical cancers. However, the inhibitory effect and underlying mechanism of HEL in gastric cancer have not been elucidated. Here, HEL significantly inhibited the growth of gastric cancer MGC803 cells in vitro and in vivo. HEL decreased expression and transcriptional regulatory activity of c-Myc and mRNA expression of c-Myc target genes. HEL enhanced mitochondrial oxidative phosphorylation (OXPHOS) and reduced glycolysis as evidenced by increased mitochondrial adenosine triphosphate (ATP) production and excessive reactive oxygen species (ROS) accumulation, and decreased the pPDHA1/PDHA1 ratio and Glyco-ATP production. Pyruvate enhanced OXPHOS after HEL treatment. c-Myc overexpression abolished HEL-induced inhibition of cell viability, glycolysis, and protein expression of PDHK1 and LDHA. PDHK1 overexpression also counteracted inhibitory effect of HEL on cell viability. Conversely, c-Myc siRNA decreased cell viability, glycolysis, and PDHK1 expression. NAC rescued the decrease in viability of HEL-treated cells. Additionally, HEL inhibited the overactivated mTOR/p70S6K pathway in vitro and in vivo. HEL-induced cell viability inhibition was counteracted by an mTOR agonist. mTOR inhibitor also decreased cell viability. Similar results were obtained in SGC7901 cells. HEL repressed lactate production and efflux in MGC803 cells. These results revealed that HEL inhibits gastric cancer growth by targeting mTOR/p70S6K/c-Myc/PDHK1-mediated energy metabolism reprogramming in cancer cells. Therefore, HEL may be a potential agent for gastric cancer treatment by modulating cancer energy metabolism reprogramming.

China's long march to malaria elimination: a case of adaptive management

Since the 1950s, China has transitioned from a malaria pandemic country with tens of millions of annual cases, through phases of local control and elimination, to sustained national malaria elimination efforts. This marks the first time a country in the World Health Organization (WHO) Western Pacific region has been certified malaria-free in more than 3 decades. This article provides an innovative approach to understanding China’s malaria elimination journey. A number of articles and commentaries have analysed the effectiveness of specific technical approaches implemented in China. Our argument is that we need to look beyond these, and consider the ways in which policy development and implementation capacities have been fostered to support the dynamic change management. The article makes a number of arguments. First is the pragmatic adaptiveness of policies and strategies—and implementation capacities. Second, China has invested in building systems as well as capacities to support the elimination of parasitic diseases, including malaria. Third, the country has both benefited from, and contributed to, global health collaboration on malaria elimination. The ongoing work by the authors is identifying a number of key factors.

[Soil-crop Distribution and Health Risk Assessment of Organochlorine Pesticides on Typical Agricultural Land in Southern Leizhou Peninsula]

The residual content of organochlorine pesticides (OCPs) in soil and crops of typical agricultural land in the southern Leizhou peninsula were determined using gas chromatography-mass spectrometry (GC-MS). Additionally, the bioconcentration factors of organochlorine pesticides in eight crops were investigated, and the human health risk was evaluated. The results indicated that 10 types of OCPs were detected to varying degrees; HCHs and heptachlor were the main OCPs in the study area, with the residual contents of 23.83-111.51 ng·g^-1 and 11.01-25.97 ng·g^-1 in soil and 7.54-61.28 ng·g^-1 and 3.96-30.97 ng·g^-1 in crops, respectively. A small number of soil and crop samples were found to exceed the standard. The ratio of α-HCH/γ-HCH was less than 1 in 87.50% of the soil samples, and β-HCH/α-HCH was larger than 1. This indicates that the HCHs were probably derived from the recent use of lindane and historical residual pollution, whereas the heptachlor was mainly derived from underground insect pests and the application of termite control agents. The enrichment ability of OCPs was significantly different among different crops. The bioaccumulation capacity of vegetables was higher than that of fruit. Furthermore, bulb vegetables (leeks) were significantly stronger than other vegetables. A human health risk assessment of OCPs showed that OCP-combined pollution would not cause significant health risks to the population in the study area. However, the maximum value of HI in some crop samples was greater than 1, indicating that there were still potential risks, which should not be ignored.

[Galangin enhances autophagy by inhibiting NF-κB pathway in gastric cancer MGC-803 cells]

This study aimed to explore the effects of galangin on energy metabolism and autophagy in gastric cancer MGC803 cells and the underlying mechanism. Cell counting kit-8(CCK-8) was used to detect the effects of galangin at different concentrations on via-bility of MGC803 cells after 48 h intervention. Western blot was carried out to measure the effects of galangin on expression of proteins related to autophagy, nuclear factor-κB(NF-κB) pathway and energy metabolism, followed by the determination of its effects on mRNA expression of energy metabolism-related proteins by Real-time quantitative PCR(qPCR). The impact of galangin on autophagy was explored using AutophagyGreen dye reagent, with autophagosomes and lysosomes observed under the transmission electron microscope(TEM). Nude mice transplanted with gastric cancer MGC803 cells via subcutaneous injection were randomly divided into the following three groups: control(0.5% sodium carboxymethyl cellulose, once a day), 5-fluorouracil(5-FU, 50 mg·kg~(-1), twice a week), and galangin(120 mg·kg~(-1), once a day) groups. The body weight and tumor volume were measured once every three days with a vernier caliper at the same time point by the same person. After 21-d treatment, the tumor tissue was isolated and weighed for the calculation of the tumor-suppressing rate. The comparison with the control group revealed that galangin inhibited the viability of MGC803 cells, up-regulated the protein expression of microtuble-associated protein 1 light chain 3 B(LC3 B) Ⅱ, inhibited the phosphorylation of NF-κB pathway-related proteins, and promoted the formation of autophagosomes in MGC803 cells. However, it did not obviously affect the expression of energy metabolism-related proteins. Furthermore, galangin at 120 mg·kg~(-1) significantly reduced the tumor weight and volume in mice, enhanced LC3 BⅡ protein expression, and inhibited the phosphorylation of NF-κB pathway-related proteins. All these have suggested that galangin inhibited the growth of gastric cancer MGC803 cells both in vivo and in vitro, possibly by inhibiting the NF-κB pathway and enhancing autophagy.

[Performance of matrix assisted laser desorption ionization time of flight biotyper system in clinical bacteria identification]

Objective: To evaluate the performance of MALDI Biotyper system in identification of clinically isolated pathogens so as to provide a new rapid identification method. Methods: Total 21 270 pathogens strains, isolated from the First Affiliated Hospital of Fujian Medical Universityduring Nov. 2015 to Dec. 2016, were identified by VITEK-Ⅱ, API and MALDI Biotyper system, respectively.The isolated strains were confirmed by DNA sequencing. Results: The identification of common bacteria with MALDI Biotyper and phenotypic system is highly consistent (>95% and >90%). Among 43 strains of anaerobic bacteria, MALDI Biotyper could identify 90.7% bacteria to species level and 97.7% bacteria to genus level with the statistical significance(χ(2)=6.76, P<0.01), while phenotypic system only identified 65.1% bacteria to species and 69.8% bacteria to genus. Also, no statistical significance was shown for Trichosporon and Candida(P>0.05). MALDI Biotyper could identify 76% filamentous fungi and all of Actinomycetes, Nocardia, Mycobacterium and Legionella to genus level. Conclusions: MALDI Biotyper is an easy-performed, sensitive method for the identification of clinically isolated pathogens. Additionally, the pretreatment and reference database has the effect on identification.

Interaction of polymorphisms in xeroderma pigmentosum group C with cigarette smoking and pancreatic cancer risk

The aim of the present study was to evaluate the association between xeroderma pigmentosum group C (XPC) polymorphisms and pancreatic cancer (PC) risk. A total of 7 XPC tagging SNPs (tag-SNPs) were selected from the International HapMap Project Databases (rs2228001A/C, rs2470353G/C, rs2228000C/T, rs3731114C/G, rs3729587G/C, rs2607775C/G and rs3731055G/A) and were genotyped in 205 patients with PC and 230 non-cancer control subjects using a SNaPshot assay. The C allelic gene frequency of rs2470353 was higher in patients with PC compared with that in the control group (P=0.003). Compared with the GG gene type, PC risk was increased in subjects with GC and GC+CC gene types (P=0.012 and P=0.006, respectively). PC risk increased 3.505-fold for the subjects who were heavy smokers (tobacco, ≥25 packets/year) with the GC+CC gene type (P=0.008). The G allelic gene frequency of rs2607775 was higher in PC patients compared with that in the control group (P=0.003). Compared with the CC gene type, PC risk increased in subjects with CG and CG+GG gene types (P=0.013 and P=0.005, respectively). Furthermore, PC risk increased 3.950-fold in subjects who were heavy smokers (tobacco, ≥25 packets/year) with the CG+GG gene type (P=0.001). Haplotype analysis further revealed that the CCC haplotype of rs2228000, rs3731114 and rs3729587 increased PC risk (odds ratio, 1.610; 95% confidence interval, 1.035–2.481; P=0.034). The present study revealed that XPC gene polymorphisms could increase the risk of PC in the study population, particularly among heavy smokers.

[Expressions of IL-1α, IL-1β and IL-13 mRNA in Lung Tissue and Serum of Rats Drown in Fresh Water]

OBJECTIVES

To detect the changes of （interleukin, IL） -1α, IL-1β and IL-13 mRNA in lung tissue and serum of drown rats, and to explore the potential value for the diagnosis of drowning in forensic practice.

METHODS

Eighteen SD rats were randomly divided into drowning group, blank control group and myocardial infarction group （as control group）. The serum of right ventricular, the inferior lobe of right lung and the myocardium were taken from the rats in different groups. The expressions of IL-1α, IL-1β and IL-13 mRNA in the lung tissue and the serum of right ventricular were detected by TaqMan probe method.

RESULTS

The expression differences of IL-1α, IL-1β and IL-13 mRNA in lung tissue between drowning group and blank control group, myocardial infarction group were not statistically significant （P>0.05）. The expression of IL-1β and IL-13 mRNA in serum of right ventricular increased （ P<0.05）. The expression differences of IL-1α, IL-1β and IL-13 mRNA in serum between blank control group and myocardial infarction group were not statistically significant (P>0.05).

CONCLUSIONS

The changes of cytokines IL-1β and IL-13 mRNA in the serum of right ventricular of drown rats are statistical significance, which are highly correlated with drowning.

Efficacy of emergency exploratory laparotomy in incarcerated obturator hernia

BACKGROUND

Incarcerated obturator hernia (IOH) is a scarce type of acute surgical disease, but the mortality rate is the highest in abdominal hernias. The aim of this study was to evaluate the efficacy of emergency exploratory laparotomy (EEL) in treating incarcerated obturator hernia (IOH).

METHODS

We conducted a retrospective study of 12 female patients with IOH underwent EEL between January 2014 and March 2016. The variables which included patient characteristics, findings of CT, operative time, postoperative complications, length of hospital stay, ICU admission rate, 30-day readmission rate and mortality were analyzed.

RESULTS

The age of patients was 82.5 ± 4.2 years and the median body mass index (BMI) was 20.6 kg/m² (IQR, 18.7-21.5 kg/m²). There were 10 patients (83.3%) underwent partial intestinal resection due to partial small bowel necrosis or perforation. The total operation time was 85.7 ± 8.7 min. The time to initiation of a soft diet was 3.9 ± 0.7 days and the median length of stay was 15.0 days (IQR, 14.0-17.5 days), respectively.

CONCLUSIONS

The EEL is a clinically safe and necessary choice for early diagnosis and treatment in IOH. EEL may improve the curative effect of IOH significantly.

Contribution of DNA repair xeroderma pigmentosum group D genotypes to pancreatic cancer risk in the Chinese Han population

This study aimed to determine the association between the polymorphisms and haplotypes in the xeroderma pigmentosum group D (XPD) gene and the risk of pancreatic cancer in the Chinese Han population. SNaPshot was used for genotyping six SNP sites of the XPD gene. Comparisons of the correlations between different genotypes in combination with smoking and the susceptibility to pancreatic cancer were performed. Individual pancreatic cancer risk in patients who carry mutant C alleles (AC, CC, and AC+CC) at rs13181 increased (p < 0.05). Taking non-smoking individuals who carry the AA genotype as a reference, and non-smoking individuals who carry mutant allele C (AC+CC), the risk of pancreatic cancer increased by 3.343 times in individuals who smoked ≥ 20 cigarettes daily, 3.309 times in individuals who smoked ≥ 14 packs per year, 5.011 times in individuals who smoked ≥ 24 packs per year, and 4.013 times in the individuals who smoked ≥ 37 packs per year (P < 0.05). In addition, haplotype analysis revealed that haplotype AGG, which comprised rs13181, rs3916874 and rs238415, was associated with a 1.401-fold increase in pancreatic cancer risk (p < 0.05). We conclude that the polymorphism of XPD Lys751Gln (rs13181) in combination with smoking contributes to increased risk of pancreatic cancer in the Chinese Han population. Haplotype AGG might be a susceptibility haplotype for pancreatic cancer.

A survey of the blood supply in China during 2012-2014

OBJECTIVES

The aim of this study was to identify the status of the blood supply in China during 2012-2014.

BACKGROUND

China is a middle-income country, which contains more than 20% of the world population. Increasing the blood supply in China, along with increased healthcare coverage, involves many challenges.

METHODS

A survey questionnaire regarding blood centre activities was sent to all of the blood centres in 32 provinces via the Internet. The data were collected from the responses and analysed using Microsoft Excel 2013.

RESULTS

The total supply of whole blood and red blood cells (RBCs) in 2012 was 18 644 700 units; in 2013, 18 985 800 units; and in 2014, 19 658 800 units. A similar trend of the total platelet supply was also observed during the same period of 2012-2014, as follows: 1 019 100 units in 2012, 1 168 400 units in 2013 and 1 276 200 units in 2014. Similarly, the plasma supply was 27 529 300 units in 2012 and 27 657 600 units in 2013, which rose to 28 307 500 units in 2014. The total cryoprecipitate supply was 1 653 900, 1 891 300 and 2 366 500 units in 2012, 2013 and 2014, respectively. When the blood supply was analysed according to the geographic regional population, large differences in the rates of blood supply between regions were evident.

CONCLUSIONS

The blood product supply in China is steadily increasing. Blood centres in China continue to face challenges regarding their ability to provide a sufficient blood supply in the future.

[Significance of the seated supine positioning nystagmus for the diagnosis of benign paroxysmal positional vertigo]

Objective:To observe and assess the significance of seated supine positioning nystagmus (SSPN) in the diagnosis of benign paroxysmal positional vertigo(BPPV).Method:Two hundreds patients who were diagnosed BPPV were tested with the seated supine positioning test(SSPT) to observe SSPN,then were tested Supine roll test(SRT) and Dix-Hallpike test(DHT). According to the result of SRT and DHT,patients were divided into different groups. The positive rate and feature of SSPN in different types of BPPV was analyzed.Result:Among the 200 patients,116 cases(58.0%) of them showed SSPN. Among the 116 cases who were divided to the posterior semicircular canal BPPV(PSC-BPPV) group,72 cases of them showed SSPN. Horizontal semicircular canal BPPV(HSC-BPPV) group were 60 cases,44 cases showed SSPN. Anterior semicircular canal BPPV(ASC-BPPV) group were 4 cases and none of them showed SSPN. The direction of SSPN was a combination of torsional nystagmus with the upper pole of the eyes beating toward the affected side combined with vertical nystagmus beating upward (toward the forehead) typically in the PSC-BPPV group. Canalolithiasis of HSC were 41 cases,and 28 cases showed SSPN,and SSPN was contralesional in 22 cases(78.6%) and ipsilesional in 6 cases. Cupulolithiasis of HSC were 19 cases and 16 cases showed SSPN,and SSPN was ipsilesional in 16 cases.Conclusion:Significance of the seated supine positioning nystagmus in different types of BPPV is different.

Effect of breviscapine against hepatic ischemia reperfusion injury

BACKGROUND

Breviscapine is an active ingredient extracted from traditional Chinese medicine Erigeron breviscapus. The purpose of this study was to investigate the effect of breviscapine injection on hepatic ischemia and/or reperfusion injury.

METHODS

Forty rats were randomly divided into five groups (n = 8): Sham group, Ischemia reperfusion 1 (I/R1) + normal saline (NS) group, I/R1 + breviscapine (Bre), I/R2 + NS group, and I/R2 + Bre group. Group1 and group2 represent ischemia time for 10 min and 30 min, respectively. Breviscapine or normal saline was administered to rats (single dose of 10 mg/Kg, intravenously) 30 min before hepatic ischemia. Serum transaminases, histopathologic changes, malondialdehyde (MDA), and superoxide dismutase (SOD) in liver tissues were evaluated. The expression level of mitochondrial fusion 2 (Mfn2) was also investigated.

RESULTS

After 24-h reperfusion, based on the histopathologic analysis, compared with NS control group, the liver function was improved in breviscapine group. Liver enzymes aspartate and alanine aminotransferase levels were significantly lower in the I/R + Bre group, when compared with the I/R + NS group. Pretreatment with breviscapine reduced MDA level (P < 0.05) and increased SOD activity significantly in I/R + Bre compared with I/R + NS group. Western blot and RT-q polymerase chain reaction showed that Mfn2 was significantly downregulated in breviscapine preconditioning group as compared to normal saline control group.

CONCLUSIONS

Breviscapine preconditioning attenuates liver ischemia reperfusion injury via inhibiting liver oxidative stress reaction. The protective mechanism probably inhibits Mfn2 protein and mRNA expression.

Association of paraoxonase polymorphisms with carotid artery atherosclerosis in essential hypertension patients

We investigated the relationships between paraoxonase genetic polymorphisms and essential hypertension in carotid artery atherosclerotic patients. The study included 353 Han participants and 240 Uighur participants from Xinjiang; they were further divided into two groups: essential hypertension with carotid artery atherosclerosis (CAAD group) and essential hypertension without carotid artery atherosclerosis (control group). Genotypes were detected by PCR, followed by restriction analyses with specific endonucleases. In Han people, the M allele frequency was significantly higher in the CAAD group than in the control group. The CC/CS genotype and C allele frequencies were significantly higher in the CAAD group than in the control group. Logistic regression analysis demonstrated that PON1 55M allele [odds ratio (OR) = 1.889] and PON2 311C allele (OR = 1.692) are independent risk factors for CAAD. Combined genotype analysis showed that PON1 55M and PON2 311C alleles are independent risk factors for CAAD (OR = 1.428). In the Uighur population, the CC/ CS genotype and C allele frequencies were significantly higher in the CAAD group than in the control group. Logistic regression analysis demonstrated that the PON2 311C allele is an independent risk factor for CAAD. We conclude that the PON1 55M and PON2 311C alleles are independent risk factors for CAAD in essential hypertension patients from the Xinjiang Han population. We also conclude that the PON2 311C allele is a risk factor for CAAD in essential hypertension patients from the Xinjiang Uighur population.

Genotyping of human platelet antigen-15 by single closed-tube Tm-shift method

INTRODUCTION

Genotyping of human platelet antigens (HPA) is useful for the diagnosis and prevention of platelet alloimmune syndromes. HPA-15 might play an important role in the development of platelet alloimmune syndromes. There are several disadvantages in the conventional methods for HPA-15 genotyping. The aim of this study was to develop a new method for HPA-15 genotyping by using single closed-tube melting temperature (T(m))-shift genotyping.

METHODS

Two GC-rich tails of different lengths were attached to 5'-end of HPA-15 allele-specific PCR primers, such that HPA-15 alleles can be discriminated by the T(m)s of the PCR products. One hundred blood samples were genotyped for HPA-15 by the T(m)-shift and conventional polymerase chain reaction with sequence-specific primers (PCR-SSP).

RESULTS

The comparison of the PCR-SSP and the T(m)-shift method showed four discordant results in one hundred samples tested. Confirmatory results demonstrated that the PCR-SSP produced several errors, whereas HPA-15 genotyping by T(m)-shift is correct. The retesting results of T(m)-shift method were consistent with those of the initial testing.

CONCLUSION

The single closed-tube T(m)-shift method for HPA-15 genotyping is high-throughput, rapid, reliable, reproducible and cost-effective and it is superior to conventional PCR-SSP used in routine genotyping of HPA-15.

[Relationship between the decline of age-related renal function and central aortic pressure in healthy Uygur population]

OBJECTIVE

To study the relationship between the decline of age-related renal function and central arterial pressure (CAP) in Uygur healthy population.

METHODS

A total of 638 healthy Uygur inhabitants from Hetian region, Xinjiang province were enrolled. They were divided into 4 groups according to their ages. Their blood pressure, serum creatinine and other indicators were detected. eGFR (estimated glomerular filtration rate) was calculated by the formula of Chinese-based MDRD (Modification of Diet in Renal Disease). CAP was measured by a pulse wave analyzer including central arterial systolic blood pressure (C-SBP), central arterial pulse pressure (C-PP), augmentation pressure (AP), augmentation index (AIX) and other components.

RESULTS

CAP and brachial arterial pressure tended to increase and renal function declined with age. There were gender differences in renal function. Both AP and AIX changed with age (P < 0.05). In each group, AP and AIX increased even more significantly in females (P < 0.01). The average age of subjects with a high AIX was 52 y ± 12 y. And it was elder than that of those with a low AIX (44 y ± 13 y, P = 0.000). The renal function of those with a high AIX was lower than those with a low AIX [(121 ± 25) ml.min. (1.73 m(2))(-1)] vs (131 ± 33) ml.min. (1.73 m(2))(-1), P = 0.000]. The levels of C-PP and AP were much higher in those with a high AIX (P = 0.00). The results of multivariate analysis showed that eGFR was negatively correlated with the level of AIX (P < 0.01). And it had no relationship with the brachial artery pressure (P > 0.05).

CONCLUSION

Central arterial pressure is associated with the decline of age-related renal function. Monitoring of CAP may help to screen the high-risk patients in the elderly population. This study provides rationales for new therapeutics of protecting the aging of kidneys.

[Case-control studies on external fixator for the treatment of comminuted distal radius fractures in senile]

OBJECTIVE

To compare and analyze the clinical effects of external fixator and small splint fixator in the treatment of comminuted distal radius fracture in senile.

METHODS

From 2005.6 to 2008.6, 74 senile patients (82 sides) with comminuted distal radius fractures were divided into external fixation group (34 cases 38 sides, 27 males and 7 females, with an average of 70.05 +/- 3.70 years) and small splint fixation group (40 cases 44 sides, 29 males and 11 females, with an average of 70.30 +/- 3.48 years). The loss of volar tilting angle and ulnar inclination angle after reduction and the function scores of carpal joint after removing the fixators were compared.

RESULTS

One week after surgery, there was loss of volar tilting angle and ulnar inclination in small splint fixation (P < 0.01), and one month after removing the external fixator, the loss of angle was more obvious (P < 0.01); while the loss of angle in external fixation group was not significant (P > 0.05). After one month of removing the fixation, the functional score of wrist joint in external fixation group was obviously higher than that of the small splint fixation group (P < 0.05).

CONCLUSION

The external fixator can be adopted to treat comminuted distal radius fractures in senile, which is able to decrease the reduction loss and helpful to functional recovery.

Isolation and identification of a new hypocrellin A-producing strain Shiraia sp. SUPER-H168

A new hypocrellin A-producing strain, Shiraia sp. SUPER-H168, was isolated from tissues of bamboo, Brachystachyum densiflorum. The morphology of this strain was characterized with a light microscope and a scanning electronic microscope. The mycelia, conidia, pycnidia of fungus were observed. Small pycnidia (10-20 microm in length) full of small conidia appeared on the mycelia, which were first reported in this study. The 18S rDNA region of this strain was amplified and sequenced. Then a neighbor-joining tree of 18S rDNA was constructed. According to the result of analysis, the strain SUPER-H168 was proved to belong to the genus Shiraia. Hypocrellin A was produced by solid-state fermentation, extracted by acetone, isolated by preparative RP-HPLC, and identified by RP-HPLC, ESI-MS and ultraviolet-visible absorbing scanning with diode array detection. The HA production could reach 2.02 mg/g dry solid substrate.

[The entrapped efficiency of BSA liposome]

BSA liposomes were prepared with approximately 100 nm mean particle size under rather gentle experiment conditions, and two-colorimetric coomassie brilliant blue protein was employed to measure the free drug in the entrapped efficiency (EE%) determination of BSA liposomes. Gel filtration was used to measure the EE%, and several Sephadex gels were examined by the separation of liposomes and free drug. To determine the free drug, three methods were compared on two-colorimetric UV spectrophotography, Bradford and two-colorimetric coomassie brilliant blue, separately. Two-colorimetric coomassie brilliant blue process increased the accuracy and improved the sensitivity of the assay about 20-fold comparing with the Bradford method. Two-colorimetric coomassie brilliant blue assay appeared to be more sensitive and showed broader dynamic range to measure the free BSA in the EE% determination of BSA liposome.

p53 polymorphism in human papillomavirus-associated Kazakh’s esophageal cancer in Xinjiang, China

AIM: To investigate the relationship between p53 codon 72 polymorphism and human papillomavirus (HPV) type 16 infection in Kazakh’s esophageal cancer (EC) in Xinjiang, China.

METHODS: Encoding regions of p53 codon 72 and HPV-16 E6 were amplified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and polymerase chain reaction (PCR) methods using pairs of primary esophageal squamous cell carcinoma (SCC) tissue and corresponding normal mucosa, which were collected from 104 patients of Kazakh in Xinjiang, China.

RESULTS: Only arginine allele was detected in 70.1% (39/55) of HPV-16-E6- positive cases but only in 40.8% (20/49) of HPV-16-E6-negative cases (P < 0.05; OR, 3.53; 95%CI, 1.57-7.98). In contrast, such a significant correlation between p53 polymorphism and HPV infection was not evident in corresponding normal mucosae. The allele frequency of Arg allele in cancer cases (0.68) was higher than that in normal mucosa samples (0.54) (P < 0.05; OR, 1.80; 95%CI, 1.21-2.69).

CONCLUSION: p53 codon 72 Arg homozygous genotype is one of the high-risk genetic factors for HPV-associated SCC of Kazakh. Individuals carrying Arg allele compared to those with Pro allele have an increased risk for esophageal SCC.

Identification of the first trypanosome H/ACA RNA that guides pseudouridine formation on rRNA

In trypanosomes small nucleolar RNA (snoRNA) genes are clustered, and the clusters encode for either single or multiple RNAs. We previously reported on a genomic locus in Leptomonas collosoma that encodes for multiple C/D snoRNAs whose expression is regulated at the processing level (Xu, Y., Liu, L., Lopez-Estraño, C., and Michaeli, S. (2001) J. Biol. Chem. 276, 14289-14298). In this study we have characterized, in the same genomic locus, the first trypanosome H/ACA RNA, which we termed h1. Having a length of 69 nucleotides, h1 has the potential to guide pseudouridylation on 28 S rRNA. The h1 is processed from a long polycistronic transcript that carries both the C/D and h1 snoRNAs. The h1/rRNA duplex obeys the rules for guiding pseudouridylation. Mapping of the pseudouridine site indicated that the predicted U is indeed modified. However, in contrast to all H/ACA RNAs, h1 consists of a single hairpin structure and is the shortest H/ACA RNA described so far.

[Detection of serum Lp(a) level of coronary heart disease and its clinical significance]

OBJECTIVE

To study the association of human serum Lp(a) level and coronary heart diseases.

METHODS

Objects examined were conposed of 2 groups: CHD (39 cases) and healthy controls (52 cases). Lp (a), TC, HDL-C, TG, apoB of two groups were determined and the results were done with statistic analysis.

RESULTS

The mean serum Lp(a) concentrations (mg.L-1) in coronary heart disease group were shown higher significantly than that in the control group (P < 0.01). However, there were no significant correlation between the mean serum Lp(a) and the mean serum TC, HDL-C, TG, spoAI and aopB.(P > 0.05).

CONCLUSIONS

Serum Lp(a) level is closely related to the occurrence of coronary heart disease. Lp(a) is a single risk factor for coronary heart disease. Detecting the determination of serum Lp(a) is extremely valuable to the clinical prediction and diagnosis of CHD.

Beclin 1 contains a leucine-rich nuclear export signal that is required for its autophagy and tumor suppressor function

Beclin 1 encodes a Bcl-2-interacting coiled-coil protein with autophagy and tumor suppressor function and is monoallelically deleted in 40-75% of sporadic human breast and ovarian cancers. Beclin 1 contains a leucine-rich nuclear export signal motif raising the possibility that its autophagy and/or tumor suppressor function may require regulated, CRM1-dependent, nucleocytoplasmic transport. In this study, we show that wild-type Beclin 1 colocalizes with both intracytoplasmic organelles and nuclei in COS7 monkey kidney and MCF7 human breast carcinoma cells. Inhibition of CRM1-dependent nuclear export with leptomycin B or mutation of the nuclear export signal motif of Beclin 1 results in predominantly nuclear localization. Unlike wild-type Beclin 1, the nuclear export mutant of Beclin 1 fails to promote nutrient deprivation-induced autophagy and fails to inhibit in vitro clonigenicity and in vivo tumorigenicity of MCF7 cells. Thus, beclin 1 has a leptomycin B-sensitive leucine-rich nuclear export signal that is required for its autophagy and tumor suppressor function. These findings suggest that the CRM1 nuclear export pathway may be important in the functional regulation of autophagic growth control.

Induction of autophagy and inhibition of tumorigenesis by beclin 1

The process of autophagy, or bulk degradation of cellular proteins through an autophagosomic-lysosomal pathway, is important in normal growth control and may be defective in tumour cells. However, little is known about the genetic mediators of autophagy in mammalian cells or their role in tumour development. The mammalian gene encoding Beclin 1, a novel Bcl-2-interacting, coiled-coil protein, has structural similarity to the yeast autophagy gene, apg6/vps30, and is mono-allelically deleted in 40-75% of sporadic human breast cancers and ovarian cancers. Here we show, using gene-transfer techniques, that beclin 1 promotes autophagy in autophagy-defective yeast with a targeted disruption of agp6/vps30, and in human MCF7 breast carcinoma cells. The autophagy-promoting activity of beclin 1 in MCF7 cells is associated with inhibition of MCF7 cellular proliferation, in vitro clonigenicity and tumorigenesis in nude mice. Furthermore, endogenous Beclin 1 protein expression is frequently low in human breast epithelial carcinoma cell lines and tissue, but is expressed ubiquitously at high levels in normal breast epithelia. Thus, beclin 1 is a mammalian autophagy gene that can inhibit tumorigenesis and is expressed at decreased levels in human breast carcinoma. These findings suggest that decreased expression of autophagy proteins may contribute to the development or progression of breast and other human malignancies.

Cloning and genomic organization of beclin 1, a candidate tumor suppressor gene on chromosome 17q21

The beclin 1 (BECN1) gene encodes a 60-kDa coiled-coil protein that interacts with the prototypic apoptosis inhibitor Bcl-2. Previous studies indicate that beclin 1 maps to a region approximately 150 kb centromeric to BRCA1 on chromosome 17q21 that is commonly deleted in breast, ovarian, and prostate cancer. The complete cDNA sequence of beclin 1 encodes a 2098-bp transcript, with a 120-bp 5' UTR, 1353-bp coding region, and 625-bp 3' UTR. Hybridization screening of a human genomic PAC library identified PAC 452O8, which contains the complete beclin 1 gene. Determination of the exon-intron structure of beclin 1 reveals 12 exons, ranging from 61 to 794 bp, which extend over 12 kb of the human genome. FISH analysis of human breast carcinoma cell lines using PAC 452O8 as probe identified allelic beclin 1 deletions in 9 of 22 cell lines. Sequencing of genomic DNA from 10 of these cell lines revealed no mutations in coding regions or splice junctions. Additionally, Northern blot analysis of 11 cell lines did not identify any abnormalities in beclin 1 transcripts. These results indicate that human breast carcinoma cell lines frequently contain allelic deletions of beclin 1, but not beclin 1 coding mutations.

Resistance of interleukin-1beta-deficient mice to fatal Sindbis virus encephalitis

Interleukin-1beta (IL-1beta) concentrations are frequently elevated in central nervous system (CNS) viral infections, but the pathophysiologic significance of such elevations is not known. To examine the role of IL-1beta in CNS viral pathogenesis, we compared the natural histories of IL-1beta-deficient and wild-type 129 SV(ev) mice infected with a neurovirulent viral strain, neuroadapted Sindbis virus (NSV). We found that the incidence of severe paralysis and death was markedly decreased in NSV-infected IL-1beta-/- mice compared to NSV-infected wild-type mice (4 versus 88%, P < 0.001). Despite this marked difference in clinical outcome, no differences in numbers of apoptotic cells or presence of histopathologic lesions in the brains of moribund wild-type mice and those of clinically healthy IL-1beta-/- mice could be detected. These results suggest that IL-1beta deficiency is protective against fatal Sindbis virus infection by a mechanism that does not involve resistance to CNS virus-induced apoptosis or histopathology.

Protection against fatal Sindbis virus encephalitis by beclin, a novel Bcl-2-interacting protein

bcl-2, the prototypic cellular antiapoptotic gene, decreases Sindbis virus replication and Sindbis virus-induced apoptosis in mouse brains, resulting in protection against lethal encephalitis. To investigate potential mechanisms by which Bcl-2 protects against central nervous system Sindbis virus infection, we performed a yeast two-hybrid screen to identify Bcl-2-interacting gene products in an adult mouse brain library. We identified a novel 60-kDa coiled-coil protein, Beclin, which we confirmed interacts with Bcl-2 in mammalian cells, using fluorescence resonance energy transfer microscopy. To examine the role of Beclin in Sindbis virus pathogenesis, we constructed recombinant Sindbis virus chimeras that express full-length human Beclin (SIN/beclin), Beclin lacking the putative Bcl-2-binding domain (SIN/beclinDeltaBcl-2BD), or Beclin containing a premature stop codon near the 5' terminus (SIN/beclinstop). The survival of mice infected with SIN/beclin was significantly higher (71%) than the survival of mice infected with SIN/beclinDeltaBcl-2BD (9%) or SIN/beclinstop (7%) (P < 0.001). The brains of mice infected with SIN/beclin had fewer Sindbis virus RNA-positive cells, fewer apoptotic cells, and lower viral titers than the brains of mice infected with SIN/beclinDeltaBcl-2BD or SIN/beclinstop. These findings demonstrate that Beclin is a novel Bcl-2-interacting cellular protein that may play a role in antiviral host defense.

Quantitative fluorescence resonance energy transfer measurements using fluorescence microscopy

Fluorescence resonance energy transfer (FRET) is a technique used for quantifying the distance between two molecules conjugated to different fluorophores. By combining optical microscopy with FRET it is possible to obtain quantitative temporal and spatial information about the binding and interaction of proteins, lipids, enzymes, DNA, and RNA in vivo. In conjunction with the recent development of a variety of mutant green fluorescent proteins (mtGFPs), FRET microscopy provides the potential to measure the interaction of intracellular molecular species in intact living cells where the donor and acceptor fluorophores are actually part of the molecules themselves. However, steady-state FRET microscopy measurements can suffer from several sources of distortion, which need to be corrected. These include direct excitation of the acceptor at the donor excitation wavelengths and the dependence of FRET on the concentration of acceptor. We present a simple method for the analysis of FRET data obtained with standard filter sets in a fluorescence microscope. This method is corrected for cross talk (any detection of donor fluorescence with the acceptor emission filter and any detection of acceptor fluorescence with the donor emission filter), and for the dependence of FRET on the concentrations of the donor and acceptor. Measurements of the interaction of the proteins Bcl-2 and Beclin (a recently identified Bcl-2 interacting protein located on chromosome 17q21), are shown to document the accuracy of this approach for correction of donor and acceptor concentrations, and cross talk between the different filter units.

Expression of a biologically active antiviral antibody using a sindbis virus vector system

Monoclonal antibodies to the Sindbis virus E2 envelope glycoprotein protect mice against lethal encephalitis and mediate viral clearance from neurons. To facilitate structure-function analyses of anti-E2 mAbs, we developed an expression system that can be used for the construction of genetically engineered anti-E2 mAbs. We constructed recombinant Sindbis/immunoglobulin gene chimeric viruses that express heavy and light chains of an anti-E2 monoclonal antibody, R6. We used a PCR-based strategy to clone the entire rearranged heavy and light chain genes from R6 hybridoma cell cDNA into a double subgenomic Sindbis virus vector. The recombinant viruses, SIN/R6L and SIN/R6H, were generated by transfecting BHK-21 cells with in vitro transcribed RNA from Sindbis virus/R6 light chain and Sindbis virus/R6 heavy chain cDNA clones, respectively. Twelve hours after co-infection of BHK cells with SIN/R6L and SIN/R6H, the tissue culture supernatant contained up to 1.4 mg/ml of recombinant R6 IgG. The heavy and light chains of recombinant R6 were associated as judged by co-purification on protein A/G sepharose and co-electrophoresis of non-reduced proteins. The ELISA reactivity to Sindbis virus antigen was similar for recombinant R6 and R6 purified from ascites fluid. Furthermore, the in vivo biologic activity of recombinant R6 was similar to that of R6 purified from ascites; recombinant R6 treatment completely protected Balb/cJ mice from paralysis and death due to infection with neuroadapted Sindbis virus and also resulted in the clearance of infectious virus from the brains of immunodeficient scid mice persistently infected with wild-type Sindbis virus. Thus, the co-infection of BHK cells with SIN/R6L and SIN/R6H leads to the expression, assembly, and secretion of a biologically active recombinant antiviral antibody. Our results suggest that the Sindbis virus vector system is a simple and powerful tool for the production of functional, genetically engineered antibodies.

Dominant inhibitory Ras delays Sindbis virus-induced apoptosis in neuronal cells

Mature neurons are more resistant than dividing cells or differentiating neurons to Sindbis virus-induced apoptotic death. Therefore, we hypothesized that mitogenic signal transduction pathways may influence susceptibility to Sindbis virus-induced apoptosis. Since Ras, a 21-kDa GTP-binding protein, plays an important role in cellular proliferation and neuronal differentiation, we investigated the effect of an inducible dominant inhibitory Ras on Sindbis virus-induced death of a rat pheochromocytoma cell line, PC12 cells. Dexamethasone induction of dominant inhibitory Ras (Ha Ras(Asn17)) expression in transfected PC12 cell lines (MMTV-M17-21 and GSrasDN6 cells) resulted in a marked delay in Sindbis virus-induced apoptosis, compared with infected, uninduced cells. The delay in death after Sindbis virus infection in induced versus uninduced PC12 cells was not associated with differences in viral titers or viral infectivity. No delay in Sindbis virus-induced apoptosis was observed in Ha Ras(Asn17)-transfected PC12 cells if dexamethasone induction was initiated less than 12 h before Sindbis virus infection or in wild-type PC12 cells infected with a chimeric Sindbis virus construct that expresses Ha Ras(Asn17). The delay in Sindbis virus-induced apoptosis in induced Ha Ras(Asn17)-transfected PC12 cells was associated with a decrease in cellular DNA synthesis as measured by 5'-bromo-2'-deoxyuridine incorporation. Thus, in PC12 cells, inducible dominant inhibitory Ras inhibits cellular proliferation and delays Sindbis virus-induced apoptosis. These findings suggest that a Ras-dependent signaling pathway is a determinant of neuronal susceptibility to Sindbis virus-induced apoptosis.

Bcl-2 protooncogene expression in cervical carcinoma cell lines containing inactive p53

Bcl-2 protein expression has been found to block apoptosis and its overexpression has been implicated in lymphoid malignancies where the chromosomal translocation t(14;18) is present. In this study we investigated bcl-2 transcription and protein expression in cultured cervical carcinoma cell lines and keratinocytes. Western blotting and immunofluorescence microscopy demonstrated bcl-2 expression in the cytoplasm of 4 out of 5 cervical carcinoma cell lines examined (HeLa, CaSki, C-33A, and HT-3, but not SiHa). Bcl-2 protein expression was undetectable in normal keratinocytes. None of the cell lines examined demonstrated chromosomal translocation or rearrangement at the major breakpoint-cluster region (MBR) of the bcl-2 gene using either Southern blot or polymerase chain reaction (PCR) analyses. Northern blot analysis demonstrated low levels of bcl-2 transcription in HeLa, CaSki, and C-33A cell lines while reverse transcriptase (RT)-PCR demonstrated bcl-2 transcription in all cervical carcinoma cell lines which had bcl-2 protein expression. Thus, these data suggest that bcl-2 expression occurs in cervical carcinoma cell lines in the absence of chromosomal translocation or rearrangement of the bcl-2 gene. However, each of these cervical carcinoma cell lines contains inactive p53, either due to mutation (C-33A and HT-3) or via complexation and degradation with human papillomavirus (HPV) 16/18 E6 protein (HeLa and CaSki). Thus, functional p53, which can induce apoptosis in certain cells, is not present in these cervical cells which have increased bcl-2 expression. Increased bcl-2 expression under conditions of p53 inactivation may provide cells with a selective advantage for survival and consequently play a role in the development of cervical carcinogenesis.

Co-localization of the tumor-suppressor protein p53 and human papillomavirus E6 protein in human cervical carcinoma cell lines

The loss of the tumor-suppressor activity of p53, either by mutation or by interaction with the human papillomavirus (HPV) E6 protein, is considered to be an important mechanism in the carcinogenesis of cervical cancer. We have studied the cytological distribution of these proteins in human cervical carcinoma cell lines using polyclonal anti-p53 and monoclonal anti-E6 antibodies. The antibody specificity was confirmed by immunoblot and immunocompetition analyses. The intracellular localization of p53 and E6 was detected using the techniques of conventional and three-dimensional confocal microscopy. In the HPV-18 or -16 integrated cell lines, HeLa, CaSki and SiHa, viral oncoprotein E6 and endogenous tumor-suppressor protein, p53, were observed by immunofluorescence in the cytoplasm; p53 also had a weak punctate staining in the nuclei of HeLa and CaSki cells. In the HPV-negative cervical carcinoma cell lines, C-33A and HT-3, which have mutated p53, p53 was localized predominantly to the nucleus, with C-33A cells having elevated levels of p53 compared with the other cell lines. High spatial resolution imaging, using confocal microscopy, was performed on the cells after double fluorescence staining for p53 (fluorescein) and E6 (rhodamine). The images showed that both p53 and E6 had similar cytoplasmic distributions, which implied that these two proteins may exist as a cytoplasmic complex. To substantiate this implication, fluorescence resonance energy transfer microscopy was performed, which provided direct evidence of a close association between p53 and E6 within individual HeLa cells. The results from this study support the theory that p53 protein binds HPV-16/18 E6 protein in the cell cytoplasm, thus preventing p53 from exerting its tumor-suppressor function in the nucleus. Hence, inactivation of wild-type p53 by p53-E6 complex formation in cervical cancer may be a critical step in malignant transformation.

[Clonal origin of intrahepatic recurrence after resection of hepatocellular carcinoma]

Using integrated hepatitis B virus (HBV) DNA in the cancer cells as a genetic marker, clonal origin of intrahepatic recurrence of hepatocellular carcinoma was studied by Southern blot technique. Comparing 5 cases of postoperative recurrent hepatocellular carcinoma with their primary tumors, it was found that 1 case had identical HBV DNA integration patterns, 3 cases were of different clonality and 1 case with multiple nodular recurrences contained either a unicentric origin or a new distinctive clone origin. The results suggest that, in addition to recurrence from residual cancer cells, in some cases, hepatocellular carcinoma may develop repeatedly during a continuous process of carcinogen action, even after a radical resection.

Resection of hepatocellular carcinoma: oligocentric origin of recurrent and multinodular tumours

The structure of integrated hepatitis B virus (HBV) DNA was analysed to determine the origin of recurrent and multinodular hepatocellular carcinoma (HCC). In 5 cases, recurrent tumours were compared with the respective primary tumours, all of which had chromosomally integrated viral DNA. In only one of these cases, an identical HBV DNA integration pattern was found, indicating a monocentric origin of primary and secondary tumour. In all other cases a polycentric origin was deduced. Particular features observed were: (i) the apparent absence of integrated viral DNA in a recurrent tumour; and (ii) an integration pattern identical to that of the primary tumour and a distinct new pattern in two different foci of multinodular recurrent HCC. For multinodular primary HCC one case was analysed and found to be of independent origin.

Replication of hepatitis B virus in a hepatocellular carcinoma

Hepatitis B virus transcripts and DNA from paired samples of neoplastic and nonneoplastic liver tissue of HBsAg seropositive patients were analyzed. The data obtained support the view that transcription of integrated DNA is frequent, both in neoplastic as well as in nonneoplastic liver tissue. In the case of one patient, integrated and free forms of hepatitis B virus DNA were detected in the tumor. Complete cycles of viral replication in this tumor were suggested by the following markers: (i) DNA and RNA intermediates expected to occur during replication of the viral genome, (ii) HBcAg and HBsAg, (iii) core and Dane particles. Viral DNA cloned from tumor tissue was proven to be replication competent in a transient replication assay. Five independent clones of viral DNA were established and found to be closely related at the nucleotide level. A preX open reading frame and a stop codon within preC were common features. In tissue surrounding the tumor, a nonreplicative state of virus infection prevailed, characterized by free viral DNA exclusively of the covalently closed, circular form. The replication of the viral DNA appeared to be blocked at the level of transcription.

Low incidence and high titers of antibodies to hepatitis B virus X-protein in sera of Chinese patients with hepatocellular carcinoma

Sera of patients from China with hepatocellular carcinoma (HCC) were tested for the presence of HBc/HBe- and HBx antibodies by immunoblotting using recombinant MS2 or beta gal fusion proteins as substrate. Antibodies against HBx were detected in four out of 68 HBsAg positive and in one out of three HBsAg negative sera, antibodies against HBc/HBe in 52 and two serum samples, respectively. Competition experiments in which sera were preincubated with individual viral proteins synthesized in E. coli were carried out to demonstrate the specificity of signals obtained in immunoblot analyses. In the five anti-HBx positive sera, the antibody titer against X fusion protein was higher than against core fusion protein and in one of these sera anti-x activity could be demonstrated even at a serum dilution of 1:50,000. These data indicate that X antibodies occur rarely in Chinese patients and are not serodiagnostic for HCC. The high titer of X antibodies in some patients shows that the X protein can be highly immunogenic in vivo. Induction of antibody formation may be triggered by X protein expressed from integrated viral DNA.