[Molecular epidemiology of Japanese encephalitis viruses isolated in Yunnan province, 1977-2010]

Objective: To understand the genetic and molecular epidemiologic characteristics of 63 strains of Japanese encephalitis virus (JEV) isolated in Yunnan province, China during 1977-2010. Methods: Suckling mice were inoculated with viruses continuously and the viral nucleic acid were extracted from the brain-grinding supernatants of the infected and moribund mice, then the gene fragments of E region were amplified by RT-PCR. Bioinformatics (Clustal X, DNAstar, Mega 5.0 and other software) was used to analyze the nucleotide and deduced amino acid sequences and phylogenetic trees. Results: Yunnan strains of JEV could cause illness and deaths in suckling mice. The results of virus nucleic acid detection and sequencing indicated that nucleotide sequences of E gene of the 63 virus strains were obtained. Phylogenetic tree and homology analyses based on E genomes showed that 47 strains of the experimental virus belonged to genotype 1 (G-1) and 16 strains belonged to genotype 3 (G-3). The 47 isolates of G-1 were divided into 2 clades, of them, the earliest isolates of G-1 (M28, 1977 and BN82215, 1982) in Yunnan of China and the early isolates of G-1 (U70416, 1982; DQ084229, the year is unknown) in Thailand were in one clade, and the isolates of G-1 from 2007-2010 in Yunnan could be divided into 2 subgroups. The 16 isolates of G-3 from Yunnan were divided into 3 clades, among them, the isolates from 1970-1990s in Yunnan were in two clades, and the isolates from 2004 in Yunnan were in one clade. In addition, their main amino acid sites of antigenicity, pathogenic, virulence of both G-1 and G-3 had no significant change. Conclusion: JEV G-1 and G-3 co-circulated in Yunnan, and G-1 was predominant. The JEV strains isolated in different years and areas in Yunnan had different molecular epidemiologic characteristics and genetic diversity. The results of this study suggested that JEV G-1 might originate from Yunnan of China and adjacent Southeast Asia region.

Distinctive effect of 6% hydroxyethyl starch 130/0.4 (Voluven) infusion on pediatric patients with congenital heart disease

OBJECTIVE

It has not been clear that Voluven (6% hydroxyethyl starch 130/0.4) may be administered in pediatric patients safely. The purpose of this study was to determine if Voluven could be used for blood volume expansion and hypovolemia prevention in pediatric patients with congenital heart disease.

PATIENTS AND METHODS

50 pediatric patients with congenital heart disease were recruited in the study. Circulatory and respiratory parameters were determined to monitor the responses to intravenous infusion of Voluven in the patients.

RESULTS

Intravenous infusion of Voluven significantly increased levels of colloid osmotic pressure and central venous pressure, but decreased levels of hemoglobin in the patients. Voluven infusion did not significantly affect colloid osmotic pressure, central venous pressure, hemoglobin and heart rate in the preschool children (<6 years old), and similarly, low infusion (100-240 mL per patient) of Voluven did not significantly affect colloid osmotic pressure, central venous pressure, hemoglobin and heart rate in the young child patients. Also, there was the similar response, i.e. increased colloid osmotic pressure, to Voluven infusion in both female child patients and patients with atrial septal defect.

CONCLUSIONS

Voluven may be used in pediatric patients with congenital heart disease, but not in the preschool child patients. Furthermore, special attention should be paid to the intravenous administration of Voluven for blood volume expansion and hypovolemia prevention in female pediatric patients and child patients with atrial septal defect.

Immunoregulatory effect of neuronal-like cells in inducting differentiation of bone marrow mesenchymal stem cells

OBJECTIVE

To evaluate the immune activity of bone marrow mesenchymal stem cells (BMSCs), and explore the biological characteristics and capabilities of BMSCs and the potential to be differentiated into neuronal cells in vitro.

MATERIALS AND METHODS

The BMSCs were isolated and proliferated in vitro to generate the xenogeneic mixed lymphocyte reaction. Moreover, peripheral BMSCs (pBMSCs) were added according to different ratios, which methods were stated as follows: 1: Dulbecco's Modified Eagle Medium (DMEM) + 10% Fetal Bovine Serum (FBS) + 1 μmol/L all-trans-retinoic acid (ATRA) + 20 μg/L basic fibroblast growth factor (bFGF) + 20 μg/L epidermal growth factor (EGF); 2: DMEM + 2% dimethyl sulfoxide (DMSO) + 100 μmol/L butylated hydroxyanisole (BHA). The immunofluorescence and immunohistochemical staining were finally used to evaluate the differentiation capabilities of human BMSCs (hBMSCs) induced in neuronal cells.

RESULTS

hBMSCs inhibited the lymphocyte proliferation in the mixed lymphocyte reaction (MLR) system at a proportional inhibition rate with additional numbers of stem cells. At hour 2 after culture with method 1, the plasma of hBMSCs shrank to nuclei and perinuclear bodies and was visualized under the light microscope. At hours 3-5, most of the hBMSCs formed neuron-like cells with total cell number unchanged. Afterward, the hBMSCs turned into bipolar or multipolar shaped cells and interconnected into a large network at Day 3. With immunofluorescence and immunohistochemical staining, 60-70% of the hBMSCs showed neurospecific enolase (NSE) positive and 45-50% glial fibrillary acidic protein (GFAP) positive while the Nestin-positive cells decreased to 3.4%. However, when cultured 2 hours with method 2, the most of the hBMSCs formed bipolar or multipolar shaped cells, then died after 48 hours. 40-50% NSE and 35-40% GFAP were positively expressed. Significantly, the rate of Nestin-positive cells decreased from 63% to 1.6% from hour 2 after culture to hour 48.

CONCLUSIONS

hBMSCs may be effective for cell therapy and tissue engineering for the capability of differentiating into neuronal-like cells, as well as the capability of inhibiting lymphocyte proliferation in MLR system.

Effect of the nucleotides surrounding the start codon on the translation of foot-and-mouth disease virus RNA

As for the alternative AUGs in foot-and-mouth disease virus (FMDV), nucleotide bias of the context flanking the AUG(2nd) could be used as a strong signal to initiate translation. To determine the role of the specific nucleotide context, dicistronic reporter constructs were engineered to contain different versions of nucleotide context linking between internal ribosome entry site (IRES) and downstream gene. The results indicate that under FMDV IRES-dependent mechanism, the nucleotide contexts flanking start codon can influence the translation initiation efficiencies. The most optimal sequences for both start codons have proved to be UUU AUG(1st) AAC and AAG AUG(2nd) GAA.

[Genetic characterization of varicella zoster virus in Jilin province in 2014, China]

OBJECTIVE

To clarify the genotype of wild-type strains of varicella zoster virus (VZV) in Jilin province in 2014, and to discriminate between v-Oka vaccine strains and wild-type strains.

METHODS

Vesicle fluid and throat swab samples were collected from 13 individuals with suspected VZV in Jilin province from January to December 2014. Viral DNA was extracted, the fragments of 15 open reading fragments (ORFs) were amplified by polymerase chain reaction (PCR), and viral genotypes were determined by single nucleotide polymorphisms (SNP). PCR restriction fragment length polymorphism (RFLP) was used to distinguish between wild-type strains and v-Oka vaccine strains. The results were analyzed with MEGA5 software, using the VZV reference strain sequences from GenBank.

RESULTS

The 13 suspected samples included 5 males and 8 females, aged 11-27 years (mean: (16.69±5.48) years). Sampling was performed on days 0 to 3 of suspected infection. VZV strains were detected in 8 samples, all belonging to Clade 2. There was a synonymous mutation (T>C) in SNP18082 compared with the v-Oka vaccine strain. Analysis of PCR-RFLPs showed that all 8 positive samples were wild-type strains (PstⅠ(+)BglⅠ(+)SmaⅠ(-)).

CONCLUSIONS

The study revealed that the VZV strains circulating in Jilin province in 2014 were wild-type strains belonging to Clade 2.

The localization of SP-B and influences of lipopolysaccharide on it

OBJECTIVE

Surfactant protein B (SP-B) is the only essential protein component of lung surfactant, the relationship between localization and function is very close. The localization of rat SP-B and influences of lipopolysaccharide (LPS) on it were investigated.

MATERIALS AND METHODS

The localization of SP-B protein in lung tissue was detected by immunofluorescence after challenged with intratracheal instillation of LPS. The constructed recombinant plasmid pEGFP-N2-SP-B was transfected with CCl-149 cell lines by liposome to explore the localization of SP-B in alveolar type II epithelial cells. Furthermore, the expression and function of SP-B were analyzed with LPS stimulating.

RESULTS

The proteins SP-B and SP-C showed the same pattern of expression in normal lung, and distributed in the alveolar cavity, LPS can directly affect the expression of SP-B in vivo, contrast to SP-B, the LPS-induced influences on SP-C is little. SP-B had the membrane embedded features and localized on the cell surface of CCL149 in vitro, but was influenced by LPS.

CONCLUSIONS

It is confirmed that the expression and membrane function of SP-B were decreased by stimulating LPS in lung tissue and alveolar type II epithelial cells.

Pharmacologic analyses of four chicken melanocortin-4 receptor mutations

The melanocortin-4 receptor (MC4R) is a critical regulator of mammalian food intake and energy expenditure, with receptor activation resulting in decreased food intake and increased energy expenditure. Recently, studies on role of MC4R in regulation of food intake have been extended to other species, such as chicken. Functional study of mutant MC4Rs is important in proving the causal link between MC4R mutation and production traits. Herein, we cloned chicken MC4R (cMC4R) complementary DNA and generated 4 mutant cMC4Rs (Q18H, G21R, S76L, and L299P) by site-directed mutagenesis and measured their expression by flow cytometry. Pharmacologic characteristics were analyzed with binding and signaling assays using 3 agonists. We showed that G21R had decreased cell surface and total expression (P < 0.05), whereas the other 3 mutants had similar total and cell surface expression levels as wild-type cMC4R. The 4 mutants had either decreased (Q18H, G21R, S76L; P < 0.05) or no (L299P) binding to radiolabeled [Nle(4), D-Phe(7)]-α-melanocyte-stimulating hormone (MSH). In signaling assays, Q18H was constitutively active. Q18H, G21R, and S76L had decreased responses to α-MSH stimulation (P < 0.05). L299P had decreased basal and ligand-stimulated signaling (P < 0.01). Nle(4), D-Phe(7)-MSH was the most potent agonist for cMC4R and therefore would be better suited for further in vivo studies. We conclude that the cloned cMC4R was a functional receptor and provided detailed functional data for these mutations, contributing to a better understanding of cMC4R variants associated with production traits.

Metabolic response of maize plants to multi-factorial abiotic stresses

Clarification of the metabolic mechanisms underlying multi-stress responses in plants will allow further optimisation of crop breeding and cultivation to obtain high yields in an increasingly variable environment. Using NMR metabolomic techniques, we examined the metabolic responses of maize plants grown under different conditions: soil drought, soil salinity, heat and multiple concurrent stresses. A detailed time-course metabolic profile was also performed on maize plants sampled 1, 3 and 7 days after initiation of soil drought and heat stress. The metabolic profile of maize plants subjected to soil drought was more similar to plants exposed to salt stress than to heat-stressed plants. Drought-stressed maize plants subjected to salt or heat stress showed distinct integrated metabolic profiles compared with those exposed to either stressor individually. These differences show the considerable metabolic plasticity of maize in response to different growth conditions. Moreover, glucose, fructose, malate, citrate, proline, alanine, aspartate, asparagine, threonine and one unknown compound fluctuated obviously between maize plants grown in controlled growth cabinet and a natural regime. These changes were associated with the TCA cycle and core nitrogen metabolism, and could be related to their multiple functions during plant growth. The evident stress-induced trajectory of metabolic changes in maize indicated that the primary metabolic responses to soil drought, heat and combined drought and heat stresses occurred in a time-dependent manner. Plasticity at the metabolic level may allow maize plants to acclimatise their metabolic ranges in response to changing environmental conditions.

Graphene based widely-tunable and singly-polarized pulse generation with random fiber lasers

Pulse generation often requires a stabilized cavity and its corresponding mode structure for initial phase-locking. Contrastingly, modeless cavity-free random lasers provide new possibilities for high quantum efficiency lasing that could potentially be widely tunable spectrally and temporally. Pulse generation in random lasers, however, has remained elusive since the discovery of modeless gain lasing. Here we report coherent pulse generation with modeless random lasers based on the unique polarization selectivity and broadband saturable absorption of monolayer graphene. Simultaneous temporal compression of cavity-free pulses are observed with such a polarization modulation, along with a broadly-tunable pulsewidth across two orders of magnitude down to 900 ps, a broadly-tunable repetition rate across three orders of magnitude up to 3 MHz, and a singly-polarized pulse train at 41 dB extinction ratio, about an order of magnitude larger than conventional pulsed fiber lasers. Moreover, our graphene-based pulse formation also demonstrates robust pulse-to-pulse stability and wide-wavelength operation due to the cavity-less feature. Such a graphene-based architecture not only provides a tunable pulsed random laser for fiber-optic sensing, speckle-free imaging, and laser-material processing, but also a new way for the non-random CW fiber lasers to generate widely tunable and singly-polarized pulses.

Expression and localization of Luman/CREB3 in mouse embryos during the pre-implantation period

Luman/CREB3 is a transcription factor that is a member of the cAMP-response-element-binding protein family of basic region-leucine zipper transcription factors. This protein interacts with host cell factor 1, which also associates with the herpes simplex virus protein VP16 to induce the transcription of herpes simplex virus. Currently, the physiological function of Luman/CREB3 in reproductive processes remains unclear. In this study, quantitative real-time PCR and immunofluorescence assays were used to investigate the expression and localization of Luman in mouse oocytes as well as in early embryonic development. Luman protein was detected in the germinal vesicle and metaphase II stage oocytes, and was distributed in the cytoplasm, nucleus, and polar body of the oocyte stage. However, Luman protein and mRNA expression levels were significantly (P < 0.05) increased before activation of the zygotic genome, and expression levels peaked in 4-cell embryos. Expression levels were significantly (P < 0.05) decreased following the 8-cell stage throughout the blastocyst stage. The Luman protein was also distributed in the nucleus and cytoplasm in the early preimplantation embryo and showed enhanced nuclear staining starting from the 2-cell stage embryo up to the 8-cell stage embryo. The differences in the expression and localization of Luman in mouse oocytes and early embryo suggested that Luman plays an important role in oocyte maturation and early embryonic development processes.

Effects of oleic acid on SP-B expression and release in A549 cells

OBJECTIVE

Pulmonary surfactant-associated protein B (SP-B), which is synthesized and secreted by alveolar epithelial type II cells, is crucial for normal functioning of pulmonary surfactant. Degeneration of pulmonary surfactant is the essential cause of acute lung injury (ALI). ALI is often studied in animal models using oleic acid, and the effects of oleic acid on pulmonary surfactant and SP-B are not clear. In this study, we examined the effects of oleic acid on the A549 cell line which resembles the alveolar epithelial type II cells.

MATERIALS AND METHODS

A549 cells were exposed for 24 hours to 300, 400, 500 or 600 µM of oleic acid. Cell morphological changes were observed using an inverted microscope, and cell proliferation was quantified with the Cell Counting Kit-8. Extracellular SP-B levels were assessed by ELISA, whereas intracellular SP-B expression by Western blot.

RESULTS

Oleic acid caused dose-dependent changes in cell morphology of A549 cells and decreased their proliferation. This was accompanied by release of SP-B into extracellular supernatants and corresponding decrease of intracellular levels of this protein.

CONCLUSIONS

Oleic acid causes a dose-dependent injury to A549 cells, release of SP-B into extracellular compartment, and decrease of intracellular SP-B expression. Our findings provide mechanistic insights into animal modeling of ALI with oleic acid.

p63 controls cell migration and invasion by transcriptional regulation of MTSS1

Metastasis is a multistep cell-biological process, which is orchestrated by many factors, including metastasis activators and suppressors. Metastasis Suppressor 1 (MTSS1) was originally identified as a metastasis suppressor protein whose expression is lost in metastatic bladder and prostate carcinomas. However, recent findings indicate that MTSS1 acts as oncogene and pro-migratory factor in melanoma tumors. Here, we identify and characterized a molecular mechanism controlling MTSS1 expression, which impinges on a pro-tumorigenic role of MTSS1 in breast tumors. We found that in normal and in cancer cell lines ΔNp63 is able to drive the expression of MTSS1 by binding to a p63-binding responsive element localized in the MTSS1 locus. We reported that ΔNp63 is able to drive the migration of breast tumor cells by inducing the expression of MTSS1. Notably, in three human breast tumors data sets the MTSS1/p63 co-expression is a negative prognostic factor on patient survival, suggesting that the MTSS1/p63 axis might be functionally important to regulate breast tumor progression.

Neuroprotection effect of interleukin (IL)-17 secreted by reactive astrocytes is emerged from a high-level IL-17-containing environment during acute neuroinflammation

An increase in interleukin (IL)-17A-producing cells, particularly at sites of tissue inflammation, is observed frequently, yet the mechanism is not fully understood. This study aims to dissect the role of IL-17 in autoimmunity-mediated neuroinflammation. The cytokine milieu containing elevated IL-17, which often appears in active states of autoimmunity, was mimicked in vitro by a supernatant obtained from rat peripheral blood monocytes stimulated with phorbol mystistate acetate (PMA)/ionomycin. The application of such inflammatory media on only primary cultured cerebellar granule neurones resulted in significant apoptosis, but the presence of astrocytes largely prevented the effect. The supernatants of the stimulated astrocytes, especially those that contained the highest level of IL-17, achieved the best protection, and this effect could be blocked by anti-IL-17 antibodies. Protein IL-17 inhibited intracellular calcium increase and protected the neurones under inflammatory attack from apoptosis. IL-17, but not interferon (IFN)-γ, in the inflammatory media contributed to astrocyte secretion of IL-17, which depended on the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway activation. The astrocytes that were treated with IL-17 alone or with prolonged treatment of the inflammatory media failed to produce sufficient levels of IL-17. Moreover, confirmatory data were obtained in vivo in a monophasic experimental autoimmune uveitis (EAU) in Lewis rats; in this preparation, the high-level IL-17-containing the cytokine milieu was demonstrated, along with IL-17 secretion by the resident neural cells. The antagonism of IL-17 at a late stage disturbed the disease resolution and resulted in significant neural apoptosis. Our data show a dynamic role of IL-17 in the maintenance of homeostasis and neuroprotection in active neuroinflammation.

Mini review roles of the bZIP gene family in rice

The basic leucine zipper (bZIP) genes encode transcription factors involved in the regulation of various biological processes. Similar to WRKY, basic helix-loop-helix, and several other groups of proteins, the bZIP proteins form a superfamily of transcription factors that mediate plant stress responses. In this review, we present the roles of bZIP proteins in multiple biological processes that include pathogen defense; responses to abiotic stresses; seed development and germination; senescence; and responses to salicylic, jasmonic, and abscisic acids in rice. We also examined the characteristics of the bZIP proteins and their genetic composition. To ascertain the evolutionary changes in and functions of this supergene family, we performed an exhaustive comparison among the 89 rice bZIP genes that were previously described and those more recently listed in the MSU Rice Genome Annotation Project Database using a Hidden Markov Model. We excluded 3 genes from the list, resulting in a total of 86 bZIP genes in japonica rice.

Quantitative evaluation of viable tissue perfusion changes with contrast-enhanced greyscale ultrasound in a mouse hepatoma model following treatment with different doses of thalidomide

OBJECTIVE

This study aimed to quantify intratumoural viable tissue perfusion with contrast-enhanced greyscale ultrasound to evaluate tumour response to anti-angiogenic treatment.

METHODS

H22 hepatoma-bearing mice were treated with low-dose thalidomide (Group B), high-dose thalidomide (Group C) or 0.5% carboxylmethylcellulose (Group A). Contrast-enhanced greyscale ultrasound was performed after 7 days of treatments to evaluate the percentage of non-enhanced area for each tumour; regions of interest within the enhanced area were analysed offline to determine the area under the curve (AUC), maximum intensity (IMAX), perfusion index (PI), mean transit time (MTT), time to peak (TTP) and quality of fit (QOF). Immunohistochemical analysis was performed for evaluation of microvascular density (MVD).

RESULTS

The percentage of non-enhanced area was significantly larger in Group C than in Groups A and B (p<0.05); however, there was no significant difference between Groups A and B. Treatment with thalidomide resulted in a significant decrease in AUC, PI and IMAX compared with Group A (p<0.05). Immunohistochemistry showed significant decreases in MVD in Groups B and C compared with Group A (p<0.05); however, there was no significant difference in MVD between Groups B and C. MVD was positively correlated with IMAX (r = 0.419, p = 0.023) and PI (r = 0.455, p = 0.013).

CONCLUSION

Quantitatively analysing intratumoural viable tissue perfusion enables early evaluation of tumour response to anti-angiogenic therapy before apparent changes in tumour necrosis.

Reconstruction of hypopharyngeal and cervical esophageal defect after resection of hypopharyngeal carcinoma: a new technique based on the use of bilateral platysma myocutaneous flaps

Commonly used procedures for reconstructing hypopharyngeal and cervical esophageal defects resulting from total laryngopharyngectomy (TL) are the gastric conduit or colon transposition as well as microvascularized free flaps. Herein we designed an alternative procedure utilizing bilateral platysma myocutaneous flaps (PMCFs) for the reconstruction of hypopharyngeal and cervical esophageal defects. This report summarizes the technical description of this procedure. TL and cervical esophagectomy were performed and bilateral PMCFs were harvested for reconstruction of hypopharyngeal and cervical esophageal defects in 25 patients aged between 46 and 73 years (mean 58.7 ± 16.2 years). All these patients had advanced-stage (IV) cancer with involvement of the cervical esophagus. Operative time ranged from 176 to 382 minutes (average 243 ± 91 minutes) and the mean intraoperative blood loss was 294 ± 119mL. There were six cases of anastomotic leak (24.0%) and two of them (8.0%) developed anastomotic stricture. Neither flap necrosis nor postoperative death was observed. The majority of our patients (68.0%) were restored to a normal unrestricted oral diet after surgery. The 3-year and 5-year actuarial survival rates were approximately 54.7% and 26.1%, respectively. We conclude that reconstruction of the cervical esophagus with bilateral PMCFs is a valuable method for treating advanced hypopharyngeal carcinoma.

Cytotoxicity and DNA damage induced by 1, 4-benzoquinone in v79 Chinese hamster lung cells

1,4-Benzoquinone (p-BQ) is a metabolite of benzene known to induce genotoxicity in vivo. The aim of this study was to determine whether it also produced genotoxicity in Chinese hamster V79 cells in vitro. In study 1, incubation with p-BQ at different concentrations (25-400 microM) for 2, 12, or 24 h was evaluated by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay to assess cell viability. In study 2, single-cell gel electrophoresis (SCGE) was used to detect DNA damage in V79 cells after exposure to p-BQ at different concentrations (6.25-100 microM). In study 3, reactive oxygen species (ROS) generation was measured using flow cytometry. Data showed that when V79 cells were exposed to 100 microM p-BQ for 2 h, there was a significant increase in cell lethality. DNA damage was detected at concentrations from 6.25 to 100 microM and at time points of 2, 12, and 24 h. ROS production was increased sixfold in BQ-treated (50 microM) cells compared with control. The results of this study suggest that excess production of ROS may be a potential mechanism underlying DNA damage induced by p-BQ.

Management of delayed intrathoracic esophageal perforation with modified intraluminal esophageal stent

In this article, we reviewed our experience of treatment of the delayed intrathoracic nonmalignant esophageal perforation employing modified intraluminal esophageal stent. Between February 1990 and August 2006, eight patients were included in this study. Five patients experienced sepsis. The interval time between perforation and stent placement ranged from 36 h to 27 days (average, 8.6 days). Esophageal stenting and throracotomy for foreign body removal were performed in four patients. The remaining four patients underwent stent placement and thoracostomy. Nutrition was initiated through gastrostomy after 7 to 10 days after the stenting. The stent was removed after the patients resumed oral intake of food and the esophagogram showed that perforation was closed. There was no death in this group. Signs of sepsis remitted 1 week after stent placement. Complications included stress ulcer, stimulative cough, and pneumonia each. Stent removal ranged 32 to 120 days (average 66.7) after its placement. The stent was kept in place for 4 months to prevent formation of esophageal stricture in one patient with caustic esophageal burns. The follow-up was completed in all the patients. The mean follow-up period was 59 months (range 12-180). One patient with caustic esophageal burn underwent cicatricial esophagectomy and gastric transposition 3 years later due to the esophageal stricture. Barium swallow demonstrated that there was a diverticulum-like outpouching in one patient and slight esophageal stricture at T2 and T3 level in another. One patient developed reflux esophagitis 5 years after stent removal. All the patients finally had a normal intake of food. Modified esophageal stenting is an effective method to manage the delayed intrathoracic esophageal perforation. Prevention of stent migration and its convenient adjustment might be the major advantages of this method.

Organochlorine pesticides in the soil in Linfen, China

Ten soil samples collected in Linfen were analyzed for 21 organochlorine pesticides. The concentration of total organochlorine pesticides ranged from 4.3 to 23.2 ng g(-1) in soil from urban areas and from 26.3 to 247.4 ng g(-1) in soil from industrial plants. The highest levels of contamination were observed in northwest and central Linfen, reflecting the distribution of industrial plants. The HCH and DDT profiles revealed that the sources were associated mainly with lindane and technical DDT, respectively, while HCHs in the soil of industrial plants might originate from a new source.

Prevention and management of complications after colon interposition for corrosive esophageal burns

We present our experience in the management of complications after a colon interposition for corrosive esophageal burns. From April 1976 to December 2006, 85 patients with caustic esophageal burns were included in this study. The superior belly median incision with an anterior border incision of the left sternocleidomastoid was used. Anastomosis between the colon and the cervical esophagus was performed in 68 and between the colon and pharyngeal portion in 14 patients. An esophageal scar part resection and gastric-esophageal anastomosis was performed in one patient who had been given an unsuccessful colon and jejunum interposition at another institute. An anastomotic modeling operation was performed in one patient with anastomotic stricture who had been managed with colon interposition at another institute. Exploratory thoracotomy and gastrostomy was performed in one patient who had an unsuccessful colon interposition at another institute. Seven of 14 patients (8.5% of 17.1%) died with serious complications such as aspirated pneumonia, interposition colon necrosis, abdominal wound dehiscence and degradation of swallowing and concordance function. However, others with such serious complications survived and were discharged for rehabilitation after corresponding treatment. The 25 patients (30.1%) with other mild complications were discharged for rehabilitation and corresponding management. Two patients from other institutes were discharged for rehabilitation and one was lost to follow-up. The most dangerous complication of this procedure is colon necrosis, and the stomach is the best organ for re-operation. Otherwise, aspiration in infants due to hypoplasia and degradation of swallowing co-ordination needs attention. Peri-operative management is very important, including the control of mediastinal and pulmonary infection and systemic nutritional support to avoid abdominal wound dehiscence. The platysma flap is an excellent method for the treatment of anastomotic stricture.

Management of achalasia with transabdominal esophagocardiomyotomy and partial posterior fundoplication

In this article we present our experience in the management of achalasia. From May 1988 through August 2005, 71 patients with achalasia underwent transabdominal esophagocardiomyotomy and partial posterior fundoplication. Barium swallow, manometry, and 24-h pH studies were performed in all patients preoperatively. Manometry and 24-h pH monitoring were only carried out in 58 patients at the third post-operative week and in 43 patients during follow-up, even though 52 patients were included in the follow-up. There were no operative deaths or complications. All the 71 patients were able to eat semifluid or solid food without dysphagia and heartburn at discharge. Esophageal barium studies showed that the maximum esophageal diameter decreased 2.2 cm and the minimum gastroesophageal junction diameter increased 8.4 mm after operation. Manometry examination in 58 patients revealed that the lower esophageal sphincter resting pressure decreased 15.0 mmHg in the wake of the procedure. Twenty-four hour pH monitoring demonstrated that reflux events were within the normal post-operative range. Fifty-five of the 58 patients had normal DeMeester scores. Among the patients with a mean 90-month follow-up, 49 patients had normal intake of food without reflux, the remaining three had mild dysphagia without requiring treatment. All the patients resumed their preoperative work and social activities. The manometry and 24-h pH studies in the 43 patients showed there were no significant changes between the third post-operative week and during follow-up. Transabdominal esophagocardiomyotomy and posterior partial fundoplication are able to relieve the functional outflow obstruction of the lower esophageal sphincter, obviate the rehealing of the myotomy edge and prevent gastroesophageal reflux in patients who have undergone myotomy alone.

Identification of helicobacter species in human liver samples from patients with primary hepatocellular carcinoma

AIMS

Several studies have shown the presence of helicobacter species in the human biliary tract and in the intestinal tract of animals. Experimental infection by Helicobacter hepaticus in mice causes chronic hepatitis and hepatocellular carcinoma (HCC). This study investigated whether helicobacter species could be detected in the liver of patients with HCC.

METHODS

Liver samples from 20 patients with primary liver carcinoma diagnosed by histopathology and 16 controls without primary liver carcinoma were studied. Histology with standard and immunohistochemical stains, culture, and polymerase chain reaction (PCR) amplification using helicobacter genus specific 16S rRNA primers were used to detect the presence of bacteria. Amplified products were identified by Southern hybridisation and sequencing. A search for other genes specific for Helicobacter pylori was also performed.

RESULTS

Helicobacter species 16S rDNA was found in eight of 20 samples of primary liver carcinoma, whereas none of the controls harboured this rDNA. Six helicobacter specific PCR amplicons were sequenced and were found to have 98.5-99.0% similarity to the 16S rDNA of H pylori. Of the eight positive samples, seven were positive in PCR using 26 kDa protein primers and six showed morphological and immunohistochemical evidence of H pylori. The cagA and glmM genes were detected in only two samples. The vacA and rps4 genes were not detected.

CONCLUSIONS

Helicobacter can be present in the liver of patients with primary liver carcinoma and is probably linked to the carcinogenic process in the liver.

Molecular genetic and biochemical analysis of woodchuck (Marmota monax) MHC class I polymorphism

The woodchuck (Marmota monax) is an animal model that is used in the study of human hepatitis B virus ( HBV ) infection. A knowledge of woodchuck MHC class I (Mamo-I) genes and gene products is therefore essential for understanding the antigen-specific T-cell responses in this animal model. A number of Mamo-I genes have been identified by molecular cloning and sequencing. However, the allelic nature of these genes has not been proven by classical genetics like the segregation analysis in families. In this study, we analyzed the allelic diversity of Mamo-I in two three-generation woodchuck families including 15 members by sequencing of Mamo-I genes and immunoblotting of Mamo-I proteins after one-dimensional isoelectric focusing (1D-IEF). In addition to four published Mamo-I alleles, six new alleles that belonged to the same locus as the known Mamo-I alleles (Mamo-A) were found within the two woodchuck families. A typical Mendelian segregation of Mamo-I gene and antigens was observed in the families studied. For simple and rapid detection of allelic variability of Mamo-I gene, a typing method based on the detection of PCR products amplified by sequence specific primers (SSP) has been developed and tested in 41 unrelated animals. The most prevalent allele was Mamo-A*01 with a frequency of 21.9% followed by Mamo-A*07 (12.2%). Our study established Mamo-A as a classical MHC class I locus by the polymorphic and allelic nature of Mamo-I gene in the woodchuck.