Paired-related homeobox 1 induces epithelial-mesenchymal transition in oesophageal squamous cancer

BACKGROUND

It is unclear that paired-related homeobox 1 (PRRX1) induces epithelial-mesenchymal transition (EMT) in oesophageal cancer and the specific function of PRRX1 in oesophageal cancer metastasis.

AIM

To assess the significance of PRRX1 expression and investigate the mechanism of EMT in oesophageal cancer metastasis.

METHODS

Detect the expression of PRRX1 by immunohistochemistry in oesophageal tumour tissues and adjacent normal oesophageal tissues; the PRRX1 short hairpin RNA (shRNA) or blank vector lentiviral gene delivery system was transfected into cells; cell proliferation assay, soft agar colony formation assays, cell invasion and migration assays and animal studies were used to observe cells biological characteristics In vitro and in vivo; XAV939 and LiCl were used to alter the activity of Wnt/β-catenin pathway. Immunofluorescence staining and western blot analysis were used to detect protein expression of EMT markers and Wnt/β-catenin pathway.

RESULTS

PRRX1 is expressed at high levels in oesophageal cancer specimens and is closely related to tumour metastasis in patients with oesophageal cancer. Regulation of PRRX1 expression might exert obvious effects on cell proliferation, especially the migration and invasion of oesophageal cancer cells. Moreover, silencing PRRX1 expression using a shRNA produced the opposite effects. In addition, when PRRX1 was overexpressed, inhibition of the Wnt/β-catenin pathway with XAV939 negated the effect of PRRX1 on EMT, whereas when PRRX1 was downregulated, activation of the Wnt/β-catenin pathway with LiCl impaired the effect on EMT.

CONCLUSION

PRRX1 is upregulated in oesophageal cancer is closely correlated with cancer metastasis. Additionally, PRRX1 induces EMT in oesophageal cancer metastasis through activation of Wnt/β-catenin signalling.

[Zexie Decoction regulates Akt/TFEB signaling pathway to promote lipophagy in hepatocytes]

Taking lipophagy as the breakthrough point, we explored the mechanism of Zexie Decoction(ZXD) in improving lipid metabolism in the hepatocyte model induced by palmitic acid(PA) and in the animal model induced by high-fat diet(HFD) on the basis of protein kinase B(Akt)/transcription factor EB(TFEB) signaling pathway. Co-localization was carried out for the microtubule-associated protein light chain 3(LC3) plasmid labeled with green fluorescent protein(GFP) and lipid droplets(LDs), and immunofluorescence co-localization for liver LC3 of HFD mice and perilipin 2(PLIN2). The results showed that ZXD up-regulated the expression of LC3, reduced lipid accumulation in hepatocytes, and increased the co-localization of LC3 and LDs, thereby activating lipo-phagy. Western blot results confirmed that ZXD increased autophagy-related protein LC3Ⅱ/LC3Ⅰ transformation ratio and lysosome-associated membrane protein 2(LAMP2) in vivo and in vitro and promoted the degradation of sequestosome-1(SQSTM1/p62)(P<0.05). The results above jointly explained that ZXD regulated lipophagy. Furthermore, ZXD activated TFEB expression(P<0.05) and reversed the PA-and HFD-induced decrease of TFEB nuclear localization in hepatocytes(P<0.05). Meanwhile, ZXD activated liver TFEB to up-regulate the expression of the targets Lamp2, Lc3 B, Bcl2, and Atg5(P<0.05). Additionally, ZXD down-regulated the protein level of p-Akt upstream of TFEB in vivo and in vitro. In conclusion, ZXD may promote lipophagy by regulating the Akt/TFEB pathway.

LncRNA-cCSC1 promotes cell proliferation of colorectal cancer through sponging miR-124-3p and upregulating CD44

LncRNA-cCSC1 is highly expressed in colorectal cancer (CRC). The study was designed to evaluate the function and mechanism of lncRNA-cCSC1 in cell proliferation of CRC. RT-PCR was used to measure the expression levels of lncRNA-cCSC1 in CRC cell lines. CCK-8, colony formation, EdU staining, flow cytometry and Western blot were performed to examine the effect of interference with lncRNA-cCSC1 expression on cell proliferation. miR-124-3p and the target genes of miR-124-3p were investigated using bioinformatics analysis and verified by dual-luciferase reporter, RT-PCR and Western blot. Rescue experiments were carried out to confirm the role of miR-124-3p in cell proliferation of CRC. Our results showed that cell proliferation of CRC was promoted by lncRNA-cCSC1 upregulation and inhibited by lncRNA-cCSC1 downregulation. In addition, miR-124-3p is predicted to be the target of lncRNA-cCSC1 and is negatively correlated with lncRNA-cCSC1. Moreover, the addition of miR-124-3p mimics or inhibitor reversed the effects induced by lncRNA-cCSC1 overexpression or silencing on cell proliferation of CRC. Additionally, lncRNA-cCSC1 regulated the expression level of CD44, a target gene of miR-124-3p. Finally, we studied the effects of the lncRNA-cCSC1/miR-124-3p axis on CD44. These results indicate that lncRNA-cCSC1 promotes cell proliferation of CRC through sponging miR-124-3p and upregulating CD44.

Peroxiredoxin 2 is associated with colorectal cancer progression and poor survival of patients

The present study was to investigate the clinical significance of peroxiredoxin 2 (PRDX2), an oncoenzyme, in the development and progression of colorectal cancer(CRC).We found levels of PRDX2 mRNA and protein were higher in CRC cell lines than in normal human colonic epithelial cells. PRDX2 expression was significantly up-regulated in CRC lesions compared with that in the adjacent noncancerous tissues. CRC tissues from 148 of 226 (65.5%) patients revealed high level of PRDX2 protein expression in contrast to only 13 of 226 (5.8%) PRDX2 strong staining cases in the adjacent noncancerous tissues. Increased expression of PRDX2 protein was significantly associated with poor tumor differentiation (p = 0.001), advanced local invasion (p = 0.046), increased lymph node metastasis (p = 0.008), and advanced TNM stage (p = 0.020). Patients with higher PRDX2 expression had a significantly shorter disease-free survival and worse disease-specific survival than those with low expression. Importantly, PRDX2 up-regulation was an independent prognostic indicator for stage I–III, early stage (stage I-II) and advanced stage (stage III) patients. In conclusion, our findings suggest PRDX2 up-regulation correlates with tumor progression and could serve as a useful marker for the prognosis of CRC.

Hippocampal overexpression of Down syndrome cell adhesion molecule in amyloid precursor protein transgenic mice

Down syndrome cell adhesion molecule (DSCAM) is located within the Down syndrome critical region of chromosome 21. DSCAM is a broadly expressed neurodevelopmental protein involved in synaptogenesis, neurite outgrowth, and axon guidance. We previously demonstrated DSCAM overexpression in the cortex of amyloid precursor protein (APP) transgenic mice, suggesting possible regulatory interactions between APP and DSCAM. APP mice exhibit deficits in hippocampus-dependent learning and memory. In this preliminary study, we examined age-related changes in DSCAM expression within the hippocampus in 16 APP transgenic mice (1, 3, 6 and 12 months old). Hippocampus-dependent spatial memory was assessed in APP mice and age-matched wild type littermates (WTs) using the Morris water maze (MWM). The cellular distribution of hippocampal DSCAM and total expression at both mRNA and protein levels were measured by immunohistochemistry, qRT-PCR, and western blotting, respectively. APP mice exhibited spatial memory deficits in the MWM. Intense DSCAM immunoreactivity was observed in the dentate gyrus granule cell layer and hippocampal stratum pyramidale. Total hippocampal DSCAM mRNA and protein expression levels were substantially higher in APP mice than WTs at 1 and 3 months of age. Expression decreased with age in both groups but remained higher in APP mice. DSCAM is overexpressed in the hippocampus over the first 12 months of life in APP mice, but especially during maturation to adulthood. In conclusion, these results suggest an association between DSCAM and APP mice, which is characterized by neuropathology and behavioral deficits. These results provide some clues for future studies on the role of DSCAM overexpression in the precocious cognitive decline observed in APP transgenic mice.

[Changes on patterns of sleep duration: findings from China Health and Nutrition Survey in population in 9 provinces]

Objective: To understand the changes on patterns of sleep duration of the China Health and Nutrition Survey (CHNS) cohort in 9 provinces from 2004 to 2011. Methods: Four rounds of CHNS data were used. Urban/rural, age and gender specific insufficient sleeping rates and excessive sleeping rates were analyzed. Results: In 2004, 2006, 2009 and 2011, a total of 274, 281, 329 and 304 children aged 3-5 years; 874, 806, 768 and 742 children aged 6-12 years; 789, 529, 426 and 367 children aged 13-17 years; 9 568, 9 530, 9 942 and 9 609 adults aged ≥18 years were surveyed respectively. The lowest insufficient sleeping rate was 53.9% (200/371) in 3-17 years old children in rural area in 2006, the highest insufficient sleeping rate was 77.2% (44/57) in 3-5 years old children in urban area in 2004. The insufficient sleeping rate increased in rural 3-5 years old children from 2004 to 2011. For the adults aged ≥18 years, the insufficient sleeping rate ranged from 4.2% (82/1 954) in females aged 18-44 years in 2004 and 2009 to 20.8% (211/1 015) in urban residents aged > 60 years in 2011. The insufficient sleeping rate in age-groups 44-59 years and ≥60 years increased in both males and females and in both urban area and rural area from 2004 to 2011. The gender specific excessive sleeping rate in 3-17 years old children was very low in both urban area and rural area and no difference was found in different rounds of survey. The excessive sleeping rate in adults ranged from 18.4% (569/3 093) in urban population in 2011 to 32.5% (1 617/4 969) in females in 2004. The excessive sleeping rate of adult decreased from 2004 to 2011. Conclusion: We should pay attention to the fact that the insufficient sleeping rate in adolescents is high and in increase in rural 3-5 years old children and adults aged ≥45 years.

Decreased expression of sestrin 2 predicts unfavorable outcome in colorectal cancer

Sestrin 2 is a conserved antioxidant protein that is involved in p53‑dependent antioxidant defenses and protects cells against oxidative stresses. The present study was conducted to examine the expression of sestrin 2 in colorectal cancer (CRC) and investigate a possible relationship between sestrin 2 expression and prognosis in CRC. The expression of sestrin 2 in human CRC tissues and cell lines was evaluated by immunohistochemical or immunofluorescent staining and western blot analysis. The correlations between sestrin 2 expression in human CRC tissues and clinicopathological variables, including overall survival (OS) and disease‑free survival (DFS), were analyzed. Both human CRC tissues and cell lines showed a decreased expression of sestrin 2. Furthermore, a low expression of sestrin 2 was significantly correlated with advanced tumor stage, lymphatic invasion, lymph node metastasis, vascular invasion and liver metastasis. Survival analysis showed that patients with low sestrin 2 staining had a significantly worse DFS and OS. Additionally, early or advanced stage CRC patients with a low expression of sestrin 2 had a shorter survival. In univariate analysis, the patients with low sestrin 2 expression, advanced tumor stage, lymphatic invasion, lymphatic node metastasis, vascular invasion, liver metastasis and peritoneal metastasis had shorter OS and DFS. In multivariate analysis, only low sestrin 2 expression, advanced tumor stage, lymphatic node metastasis, vascular invasion and liver metastasis remained as independent prognostic factors of poor OS and DFS. The findings suggested that a decreased expression of sestrin 2 is associated with an unfavorable prognosis, which suggests that it is a novel and crucial predictor for CRC metastasis.

Liposomal delivery and polyethylene glycol-liposomal oxaliplatin for the treatment of colorectal cancer (Review)

Oxaliplatin is effective for the treatment of advanced colorectal cancer; however, its application is restricted due to its dose-limiting toxicity. Liposomes are sphere-shaped vesicles consisting of one or more phospholipid bilayers. Liposomes as drug carriers are characterized by delayed release, lesion targeting and may be used as a drug-delivery system to decrease the side effects of cytotoxic drugs. Active targeting modification of liposomes may change the biological distribution of the anticancer agents, reduce or reverse multidrug resistance of tumor cells and enhance the effects of anticancer therapy. Based on the characteristics mentioned above, the aim of the present review was to demonstrate that polyethylene glycol-liposomes containing oxaliplatin may offer advantages for the treatment of colorectal cancer in clinical practice.

[Effects of chlorogenic acid on the viability and HIF-1alpha mRNA expression of PC12 cells exposed to hypoxia]

OBJECTIVE

To investigate the effects of chlorogenic acid on the viability and HIF-1alpha mRNA expression of PC12 cells exposed to hypoxia.

METHODS

PC12 cells were cultured in trigas incubator in order to establish the hypoxic condition. The effects of chlorogenic acid on the cells were evaluated by morphological observation, cell viability and LDH release assays as well as the examination of mRNA expression level of HIF-1alpha.

RESULTS

Chlorogenic acid significantly improved the viability of cells exposed to hypoxia, decreased LDH release, arrested the cell cycle on G1 phase, and increased the gene expression level of HIF-1alpha.

CONCLUSION

Chlorogenic acid protects PC12 cells from hypoxic damage by improving the expression of HIF-1alpha.

Effect of curcumin on human colon cancer multidrug resistance in vitro and in vivo

OBJECTIVE

To determine whether curcumin reverses the multidrug resistance of human colon cancer cells in vitro and in vivo.

METHODS

In a vincristine-resistant cell line of human colon cancer, the cell viability of curcumin-treated cells was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Rhodamine123 efflux was evaluated to detect P-glycoprotein transporter activity, and expression of the multidrug resistance protein 1 and survivin genes was analyzed by reverse transcription polymerase chain reaction and western blotting. In addition, xenograft mouse tumors were grown and treated with curcumin. The morphology of the xenografts was investigated by hematoxylin-eosin staining. The in vivo expression of the multidrug resistance gene and P-glycoprotein and survivin genes and proteins was observed using reverse transcription-polymerase chain reaction and western blotting, respectively.

RESULTS

Curcumin was not obviously toxic to the vincristine-resistant human colon cancer cells at concentrations less than 25 μM, but the growth of cells was significantly inhibited. At concentrations greater than 25 μM, curcumin was toxic in a concentration-dependent manner. The sensitivity of cells to vincristine, cisplatin, fluorouracil, and hydroxycamptothecin was enhanced, intracellular Rhodamine123 accumulation was increased (p<0.05), and the expression of the multidrug resistance gene and P-glycoprotein were significantly suppressed (p<0.05). The combination of curcumin and vincristine significantly inhibited xenograft growth. The expression of the multidrug resistance protein 1 and survivin genes was significantly reduced in xenografts of curcumin-treated mice and mice treated with both curcumin and vincristine relative to control mice.

CONCLUSION

Curcumin has strong reversal effects on the multidrug resistance of human colon carcinoma in vitro and in vivo.

Effect of hypoxia-inducible factor 1-α on Survivin in colorectal cancer

Colorectal cancer is a one of the most common malignancies. Hypoxia-inducible factor 1-α (HIF1-α) and Survivin play important roles in tumor development; however, the literature currently contains few reports on the relationship between them in colorectal cancer. In this study, we investigated the effect of HIF1-α on Survivin in colorectal cancer. Immunohistochemical staining was used to detect the expression of HIF1-α and Survivin in colorectal cancer tissue from 32 patients. Colon adenocarcinoma SW480 cells were cultured under normoxia and hypoxic conditions, and the expression of HIF1-α and Survivin was detected by RT-PCR and Western blotting. We also silenced HIF1-α in order to detect the expression of Survivin and cell apoptosis. In an in vivo xenograft tumor model, the effect of HIF1-α on cancer development and Survivin was evaluated by the measurment of tumor volume and immunohistochemical analysis. Analysis revealed that HIF1-α (75%) and Survivin (68.75%) were both overexpressed in colorectal cancer, and that their expression was correlated. They were also expressed in SW480 cells under conditions of normoxia, and exhibited a significant increase in expression under hypoxic conditions. The inhibition of HIF1-α by RNA interference decreased the expression of Survivin and led to the apoptosis of the SW480 cell line. In the in vivo xenograft tumor model, the expression of HIF1-α and Survivin was decreased in the siHIF1-α group, and the tumor volume (586.67±41.63 mm3) was much smaller than that in the negative interference (1374.67±85.87 mm3) and saline-treated (1382.80±28.42 mm3) groups. Our results indicate that HIF1-α is an important regulator of Survivin expression and has great potential capacity for cancer therapeutics.

Effects of PEG-liposomal oxaliplatin on apoptosis, and expression of Cyclin A and Cyclin D1 in colorectal cancer cells

Oxaliplatin is one of the agents used against colorectal cancer. Using PEG-liposome encapsulated oxaliplatin may enhance the accumulation of drugs in tumor cells, inducing apoptosis. However, the mechanism of action of PEG-liposome encapsulated oxaliplatin remains unclear. SW480 human colorectal cancer cells were treated with empty PEG-liposomes, free oxaliplatin or PEG-liposomal oxaliplatin. Cell cycle and apoptosis were assessed using fluorescence confocal microscopy and terminal deoxynucleotidyl transferase-mediated dUTP-fluorescein nick-end-labeling (TUNEL). Western blotting was used to analyze the expression of pro-apoptotic, anti-apoptotic and cyclin proteins. We found that PEG-liposomal oxaliplatin induced a stronger apoptotic response than empty PEG-liposomes or free oxaliplatin. Moreover, expression of Cyclin D1 increased, whereas expression of Cyclin A decreased after treatment with PEG-liposomal oxaliplatin. Furthermore, the cell cycle was arrested in the G1 phase. The results presented here indicate that PEG-liposome entrapment of oxaliplatin enhances the anticancer potency of the chemotherapeutic agent. The effect of PEG-liposomal oxaliplatin on apoptosis of SW480 human colorectal cancer cells may be through regulation of expression of Cyclin A or Cyclin D1, as well as pro-apoptotic and anti-apoptotic proteins.

PEG-liposomal oxaliplatin potentialization of antitumor efficiency in a nude mouse tumor-xenograft model of colorectal carcinoma

The non-selectivity of chemotherapeutics between normal tissue and pathological sites poses a challenge for the treatment strategy for advanced colorectal carcinoma. To obtain sufficient antitumor activity, optimization of the therapeutic regimen is of great importance. We investigated PEG-liposomal oxaliplatin potentialization of antitumor efficiency in a nude mouse tumor-xenograft model of colorectal carcinoma. A tumor-bearing nude mouse model, intravenous injections of (Dio)-labeled PEG-liposomes via tail vein and fluorescence imaging with in vivo imaging system were employed. Mice were treated with free L-oHP, PEG-liposomal L-oHP via the tail vein, followed by analysis of the accumulation of L-oHP in tumor tissues by high-performance liquid chromatography (HPLC), observation of the tumor volume and the survival rate. Apoptosis and proliferation of tumors were detected by TUNEL assay and immunohistochemistry. The mRNA and protein levels of Bcl-2, Bax, caspase-3 (P17) and Ki-67 were determined by RT-PCR and Western blotting. Fluorescence imaging with in vivo imaging showed PEG-liposome targeting in tumor tissues. After intravenous injections of PEG-liposomal oxaliplatin, tumor tissue maximum accumulation of L-oHP was 9.37 ± 0.79 µg/g at 24 h; The tumor volume was significantly suppressed, and mice showed longer survival, compared with the free oxaliplatin group. Apoptosis increased, but proliferation decreased in tumor tissues. The mRNA expression of Bcl-2 and Ki-67 was down-regulated, while Bax and caspase-3 expression was up-regulated. Protein expression of Bcl-2 was down-regulated, while Bax and P17 expression was up-regulated. The results indicate that PEG-liposomal oxaliplatin can improve antitumor efficiency in a nude mouse tumor-xenograft model of colorectal carcinoma.

Oncolytic adenovirus mediated Survivin RNA interference and 5-fluorouracil synergistically suppress the lymphatic metastasis of colorectal cancer

Colorectal cancer is one of the leading malignancies in the world. The mortality is mainly caused by tumor metastasis. It is urgent to find new therapeutics against metastatic colorectal cancer. We constructed an adenovirus carrying a Survivin targeted shRNA, tested its effects alone or with 5-fluorouracil (5-FU) both in vitro and in a nude mouse xenograft model. Results showed that the recombinant adenovirus reduced the expression of Survivin effectively, and administration of virus together with 5-FU inhibited cancer cell metastasis both in vitro and in vivo at concentrations at which each agent alone was ineffective. We conclude Survivin targeted virotherapy together with 5-FU chemotherapy may be a promising treatment for metastatic colorectal cancer.

Peroxiredoxins in colorectal neoplasms

Peroxiredoxins (Prxs) are novel group proteins with efficient antioxidant capacity, and some of them also have effects on cell proliferation, differentiation, apoptosis, and chemotherapy and radiotherapy resistance. Altogether six distinct Prxs expressions were investigated in histological samples of colorectal neoplasm and the distant normal tissues and investigated associatedly with parameters such as clinical stage and lymphnodes metastasis. Normal colorectal tissues were almost negative for Prxs, except Prx4 (15/32). In colorectal cancer tissues, the most prominent reactivity was observed with Prx2 in 23/32 cases, while the corresponding figures for others was 21/32 (Prx1), 18/32 (Prx3, Prx5, Prx6) and 8/32 (Prx4). Prx1 (P=0.023), Prx2 (P=0.012), and Prx5 (P=0.028) were the isoforms that showed significantly increased expression in colorectal cancer patients with stage III or lymphnodes metastasis-positive cases. There was a significant relationship between the expression of Prx1 and Prx2 (rs=0.425, P=0.015) and between Prx3 and Prx4 (rs=0.364, P=0.041). Additionally, 8 cases were studied by western analysis. Prx1, 2, 3, 5 and 6 were particularly elevated in tumors compared to nonmalignant tissue as assessed by immunohistochemistry. It appeared that some Prxs were upexpression in colorectal cancer tissues and may have some prognostic significance; the induction of Prxs could be explained by increased production of reactive oxygen species in carcinomatous tissue.

Oncolytic adenovirus mediated Survivin knockdown by RNA interference suppresses human colorectal carcinoma growth in vitro and in vivo

Background

Colorectal cancer is a one of the most common alimentary malignancies. Survivin has been proved by many studies to be an ideal target for cancer gene therapy because of its strong anti-apoptotic effect. The reduction of Survivin expression by means of chemically synthesized small interfering RNA or small hairpin RNA expressed from plasmid and resulted growth inhibition of cancer cells had been proved by many studies including ours, but the transfection efficiency was not encouraging. So for the first time we constructed the Survivin shRNA into an oncolytic adenovirus, tested its effects on colorectal cancer cell lines and nude mice xenograft model.

Methods

In this study, we constructed an oncolytic adenovirus with a Survivin targeted small hairpin RNA and a reporter gene (ZD55-Sur-EGFP). The expression of Survivin mRNA and protein were analyzed by RT-PCR and western blot. The cell growth and apoptosis were tested by in vitro cytopathic assay, MTT assay and flow cytometry respectively. The effect of the constructed virus on xenograft model was evaluated by tumor volume and western blot analysis.

Results

ZD55-Sur-EGFP replicated in cancer cells specifically, reduced the expression of Survivin mRNA and protein expression effectively (P < 0.0001), induced cancer cell apoptosis and inhibited SW480 cell growth both in vitro and in vivo significantly.

Conclusion

We conclude Survivin RNA interference combining with oncolytic adenovirus virotherapy to be a promising treatment for colorectal cancer.

Synthesis of GaN nanotip triangle pyramids on 3C–SiC epilayer/Si substrates via an in situ In-doping technique

GaN nanotip triangle pyramids were synthesized on 3C-SiC epilayer via an isoelectronic In-doping technique. The synthesis was carried out in a specially designed two-hot-boat chemical vapor deposition system. In (99.999%) and molten Ga (99.99%) with a mass ratio of about 1:4 were used as the source, and pieces of Si (111) wafer covered with 400-500 nm 3C-SiC epilayer were used as the substrates. The products were analyzed by x-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction, Raman spectroscopy, and photoluminescence measurements. Our results show that the as-synthesized GaN pyramids are perfect single crystal with wurtzite structure, which may have potential applications in electronic/photonic devices.

Extension of ischemic tolerance of porcine livers by cold preservation including postconditioning with gaseous oxygen

BACKGROUND

Transplantation of organs from nonheartbeating donors was recommended to reduce organ shortage. In vitro experiments with rat livers have shown that the warm ischemic tolerance of the liver may be extended by persufflation with gaseous oxygen during cold storage. The qualification of this method for procurement of livers harvested after cardiac arrest was tested in an in vivo approach with pigs.

METHODS

Livers from 15 donor pigs were explanted, heparinized, flushed with and stored in University of Wisconsin solution for 4 hr at 4 degrees C, and then implanted into 15 recipients. The organs were dissected immediately after cardiac arrest (group 1) or after 60 min of warm ischemia (groups 2 and 3). Group 2 livers received 75,000 IU of superoxide dismutase together with the flush solution and were persufflated with gaseous oxygen via the venous vascular system during cold storage. Main end point was survival after 5 days. Additionally, metabolic, functional and inflammatory criteria were measured in the blood.

RESULTS

All animals of the groups 1 and 2 survived, all animals of group 3 died within 3 hr after reperfusion. In all groups the blood parameters reflected significant damage of the livers. However, the ischemic damage was comparable in the groups 1 and 2 whereas the livers of group 3 exhibited significantly higher levels of aspartate alanine aminotransferase and lactate dehydrogenase, and a significantly elongated partial thromboplastin time 1 hr after reperfusion (P=0.016).

CONCLUSIONS

Venous systemic oxygen persufflation in combination with antioxidative medication is a promising new method of resuscitating ischemically altered livers from nonheartbeating donors for successful transplantation.

Evaluation of the effects of a pneumoperitoneum with carbon dioxide or helium in a porcine model of endotoxemia

BACKGROUND

The expansion of the laparoscopic techniques to the critically ill patient is currently under debate. In order to evaluate the potential risks of performing laparoscopy in a body with signs of sepsis, the effects of the pneumoperitoneum were studied in a porcine model of mild endotoxemia.

METHODS

Twenty-eight pigs were separated into four groups of seven animals: untreated control (C), 2 microg/kg/h endotoxin (E), endotoxin and a pneumoperitoneum (3 h, 15 mmHg) with CO2 (EC) or with helium (EH). Hemodynamic and homeostatic variables were studied for a period of 5.5 h. Primary endpoints were arterial and mucosal pH and the ATP content of the bowel wall. Statistical evaluation was performed using analysis of variance and the Bonferroni test.

RESULTS

Endotoxin infusion induced characteristic symptoms of early sepsis: increase of arterial CO2, pulmonary arterial, portal venous, and pulmonary artery wedge pressure, and decrease of arterial pressure, cardiac output, arterial and mucosal pH. An additional pneumoperitoneum led to aggravation of all criteria with significant alterations in arterial and mucosal pH, arterial CO2, wedge and portal venous pressure. The most striking derangement of mean values was observed for mucosal pH (EC: 7.40, EH: 7.54) and arterial pH (EC: 7.15, EH: 7.18). In group EC, two animals died in septic shock.

CONCLUSION

Applying a pneumoperitoneum during an ongoing sepsis significantly deteriorates hemodynamic and homeostatic variables, thus enhancing the risk of severe complications.

Preoperative high dose methylprednisolone improves patients outcome after abdominal surgery

OBJECTIVE

To assess the effect of preoperative high dose methylprednisolone on stress response and outcome.

DESIGN

Randomised, placebo-controlled, double-blind study.

SETTING

University hospital, Germany.

SUBJECTS

20 patients listed for abdominal surgery of whom 10 had major intra-abdominal interventions and 10 had incisional hernias repaired.

INTERVENTIONS

Methylprednisolone 30 mg/kg (100 ml) was given by slow intravenous infusion 90-60 minutes before operation. The control group received the same volume of sodium chloride.

MAIN OUTCOME MEASURES

Speed of convalescence, degree of fatigue, amount of pain, consumption of analgesics, breathing capacity, and hospital stay, as well as humoral and cellular mediators of the stress response.

RESULTS

Methylprednisolone significantly improved criteria of postoperative recovery, fatigue by 47%, (day 1), convalescence by about 45% (days 1-3), and breathing capacity (FEV1) between 47% and 29% (days 5, 7) (p < 0.05, ANOVA), and led to a significant reduction of median hospital stay of 4.5 days. C-reactive protein concentration was significantly decreased (by 46% on day 3) and T-cell activation was suppressed (day 1).

CONCLUSION

Outcome of the patients after conventional abdominal surgery is substantially improved by preoperative high dose methylprednisolone. This effect is more pronounced in patients having major operations.

[Effect of pneumoperitoneum on hemodynamics and intestinal integrity in endotoxinemia: CO2 versus helium]

In a study in pigs pathophysiological effects of a pneumoperitoneum (PP) established during endotoxemia (2 micrograms/kg b.w./hr) were investigated. In this situation a PP with carbon dioxide (CO2) or helium induces a deterioration of systemic hemodynamics or acid-base-stability. Some of these effects threaten vital stability. PP with either gas causes a mucosal acidosis of the small bowel within the meaning of an impairment of intestinal oxygen supply. A CO2-PP adversely affects the intestinal energy metabolism and leads to significantly increased endotoxin levels in contrast to helium after desufflation of the abdominal cavity. Data of this study at least demand for a careful monitoring, if laparoscopy is performed in septic and critically ill patients.

[Revitalizing donor livers after cardiovascular arrest with venous oxygen persufflation]

The experimental study investigates the resuscitation of livers procured from non heart beating donors by venous systemic oxygen persufflation in a pig transplantation model. In group 1 livers were harvested from donor animals after 60 min of potassium induced cardiac arrest. Livers were then flushed and preserved in 4 degrees C cold University of Wisconsin solution for 4 hrs. Then liver transplantation was performed in recipient animals. Animals of group 2 received the same treatment, but during hypothermic storage we applied venous systemic oxygen gas persufflation (VSOP) via the supra-hepatic vena cava. Livers of group 3 were harvested without warm ischemia and without oxygen treatment during cold ischemic storage and were then transplanted. All recipient animals of group 2 and 3 survived the five day follow-up time. All recipient animals of group 1 died a few hours after liver reperfusion due to circulatory shock or liver failure. The liver quality of group 2 recipient animals was similar to group 3 livers, because serum transaminase levels and blood coagulation test showed no significantly different values between those groups. Our data suggest that livers procured from non heart beating donors after 1 hr of cardiac arrest can be resuscitated and successfully transplanted by therapeutic treatment with VSOP.

Antibodies against Tetrahymena 14-nm filament-forming protein recognize the replication band in Euplotes

Tetrahymena 14-nm filament-forming protein (49K protein) is a structural protein which is involved in activity of the pronuclei during conjugation (O. Numata, T. Sugai, and Y. Watanabe (1985) Nature (London) 314, 192-194). Using monoclonal and polyclonal antibodies, we here demonstrate the presence of a cross-reactive protein (CRP-49) within the macronuclear replication bands of Euplotes harpa and E. eurystomus which is recognized by anti-49K protein antibodies. Immunoblotting reveals that both monoclonal and polyclonal antibodies cross-react to a protein with an apparent molecular mass of 50 kDa in an E. harpa cell extract and to a protein of 49 kDa in a macronuclear extract of E. eurystomus. The antibodies used in this study have no effect upon in vitro DNA synthesis in the replication band of E. eurystomus.