The anti-glioma effect of suicide gene therapy using BMSC expressing HSV/TK combined with overexpression of Cx43 in glioma cells

The disseminated neoplastic foci of malignant gliomas are essentially responsible for the limited efficacy of current available therapeutic modalities. Bone marrow-derived stem cells (BMSCs) have the ability to migrate into these tumors and even track infiltrating tumor cells, making them to be promising cellular vehicles for delivering therapeutic agents to glioma cells. The herpes simplex virus thymidine kinase (HSV-TK)/ganciclovir (GCV) suicide gene therapy with a potent bystander effect has been considered as one of the most promising therapeutic strategies for malignant gliomas. In this study, we evaluate the anti-glioma effect of suicide gene therapy using BMSCs expressing HSV-TK combined with overexpression of connexin 43 (Cx43), which can restore the gap junction of intercellular communication and may enhance the bystander effect of suicide gene therapy. To assess the potential of BMSCs to track glioma cells, a spheroid co-culture system in matrigel was used to show that some BMSCs migrated to C6 glioma cell microspheres. Transwell assay showed the tumor tropic property of BMSCs. In addition, BrdU-labeled BMSCs injected directly into the cerebral hemisphere opposite to the established C6 rat gliomas were capable of migrating into the xenograft gliomas. C6 cell growth was more intensively inhibited by HSV-TK/GCV treatment mediated by BMSCs, and could be further enhanced by combination with Cx43 transfection into glioma cells. The same result was observed in vivo by the growth of C6 gliomas and the survival analysis of rats bearing C6 glioma. In conclusion, Cx43 combined with HSV-TK/GCV gene therapy using BMSCs as vehicles was highly effective in a rat glioma model and therefore hold great potential as a novel approach for the gene therapy of human malignant gliomas.

Preoperative hepatic and regional arterial chemotherapy in the prevention of liver metastasis after colorectal cancer surgery

4090

Background: To investigate whether preoperative hepatic and regional arterial chemotherapy are able to prevent liver metastasis and improve overall survival in patients receiving curative colorectal cancer resection. Methods: Patients with Stage II or Stage III colorectal cancer (CRC) were randomly assigned to receive preoperative hepatic and regional arterial chemotherapy (PHRAC group, n=256) or surgery alone (control group, n=253). The primary endpoint was disease-free survival, whereas the secondary endpoints included liver metastasis-free survival and overall survival. Results: There were no significant differences in overall morbidity between PHRAC and Control groups. During the follow-up period (median, 42 months), the median liver metastasis time for patients with stage III CRC was significantly longer in the PHRAC group (16±3 months v.s. 8±1 months, P=0.01). In stage III patients, there was also significant difference between the two groups with regard to the incidence of liver metastasis (18.9% vs 27.3%, P=0.01), 5-year disease-free survival (70.2% vs 52.0%, P=0.0076), 5-year overall survival (80.3% vs 69.5%, P=0.020) and the median survival time (40.1± 4.6 months vs 36.3 ± 3.2 months, P=0.03). In the PHRAC arm, the risk ratio of recurrence was 0.63 (95% CI, 0.51–0.79, P=0.0001), of death was 0.50(95% CI, 0.32–0.67; P=0.005), and of liver metastasis was 0.70 (95% CI, 0.52–0.86; p=0.01). In contrast, PHRAC seemed to be no benefit for stage II patients. Toxicities, such as hepatic toxicity and leucocyte decreasing, were mild and could be cured with medicine. Conclusions: Preoperative hepatic and regional arterial chemotherapy, in combination with surgical resection, could be able to reduce and delay the occurrence of liver metastasis and therefore improve survival rate in patients with stage III colorectal cancer.

No significant financial relationships to disclose.

Endoscopic decompression using a transanal drainage tube for acute obstruction of the rectum and left colon as a bridge to curative surgery

OBJECTIVE

The aim of this study was to clarify the usefulness of the management of acute left colon and rectum obstruction because of colorectal carcinoma using a transanal ileus drainage tube before curative surgery.

METHOD

Forty-six patients (24 males and 22 females, aged 24-94 years, mean = 56.2) treated between September 2005 and March 2007 for acute left colon and rectal obstruction were identified in a colorectal obstruction database, and their clinical and radiological features were reviewed. After a cleaning enema was administered, urgent colonoscopy was performed. Subsequently, endoscopic decompression using a ileus tube was attempted.

RESULTS

Endoscopic decompression using the ileus tube was technically successful in 45 of 46 patients (97.8%). Perforation occurred in one patient 3 days later and emergent operation was performed. The site of obstruction was the rectum in 15 patients, the sigmoid colon in 18, the descending colon in 13. Following adequate cleansing of the colon, patients' abdominal girth were decreased from 91 +/- 4 cm before drainage to 82 +/- 2 cm 7 days later, and one-stage surgery after 8 +/- 1 days (SD; range 7-10 days) were performed. No anastomotic leakage or postoperative stenosis occurred after operation.

CONCLUSION

Management of acute left colon and rectum obstruction because of colorectal carcinoma using the ileus tube was found to be effective and safe, considered as a bridged method before curative surgery.

Endoscopic ultrasound-guided drainage of abdominal abscesses and infected necrosis

Traditionally abdominal abscesses have been treated with either surgical or radiologically guided percutaneous drainage. Surgical drainage procedures may be associated with considerable morbidity and mortality, and serious complications may also arise from percutaneous drainage. Endoscopic ultrasound (EUS)-guided drainage of well-demarcated abdominal abscesses, with adjunctive endoscopic debridement in the presence of solid necrotic debris, has been shown to be feasible and safe. This multicenter review summarizes the current status of the EUS-guided approach, describes the available and emerging techniques, and highlights the indications, limitations, and safety issues.

Blind adaptive filtering for non-invasive extraction of the fetal electrocardiogram and its non-stationarities

The objective is to extract automatically a beat-to-beat fetal electrocardiogram (fECG) from a maternal electrocardiogram (mECG) using surface electrodes placed on the maternal abdomen and to derive fetal PR, QT, QTc, and QS durations to allow early diagnosis and monitoring treatment of certain fetal cardiac disorders. mECG and abdominal noise in abdominal maternal recordings can be orders of magnitude stronger than the fECG signal and the P and T waves that are embedded in them. A two-stage blind adaptive filtering algorithm was used for fECG extraction, the first stage using frequency-domain electrocardiogram features and the second considering time-domain features. Three channels of abdominal recordings were obtained from 12 patients at 20–40 weeks of gestation. In each case beat-to-beat unaveraged fECGs were isolated. The combined filter allowed identification of diagnostically important PR, QT, and RR durations. Comparison with synthetic data is also included.

Influence of learning effect on blue-on-yellow perimetry

PURPOSE

Some studies have found that a significant blue-on-yellow perimetry (B/YP) learning effect exists in patients with ocular hypertension (OHT) or open-angle glaucoma who were experienced in standard automated perimetry. However, very little is known about the B/YP learning effect in normal subjects and patients without previous white-on-white perimetry (W/WP) experience. Meanwhile, it is unclear whether the B/YP learning effect is influenced by age and refraction.

METHODS

Twenty healthy subjects, 26 OHT and 14 primary open angle glaucoma (POAG) patients, underwent three full-threshold B/YP tests at intervals of 7 to 21 days. Of the 60 subjects, 38 had no previous W/WP experiences, 22 had previous W/WP experiences for at least two times. The parameters investigated to detect a learning effect were the perimetric indices and the test duration (TD).

RESULTS

Learning effects were demonstrated for mean deviation (MD), pattern standard deviation (PSD), short-term fluctuation (SF), and TD. Significant differences were found between the MD, PSD, SF, and TD of the first test and those of the second and third tests (p<0.05). However, no difference was found between those parameters of the second and third tests. No statistically significant differences were noted in terms of MD1st-2nd, MD1st-3rd, PSD1st-2nd, PSD1st-3rd, TD1st-2nd, and TD1st-3rd between the group with W/WP experience and the group without previous W/WP experience (p>0.05). No statistically significant differences were noted in terms of those parameters among the normal subjects and the patients with OHT or POAG (p>0.05). No significant difference was found in the B/YP learning effect among various age groups (p>0.05) and among various refraction groups (p>0.05).

CONCLUSIONS

A significant learning effect was observed between the first and the second or third tests and the perimetric indices appeared improved at full-threshold B/YP. The previous W/WP experience and the subject age and refraction did not influence the B/YP learning effect. This above all should be taken into account when considering the clinical use of this test to avoid erroneous diagnostic conclusions.

Three-dimensional direct writing of B35 neuronal cells

We have demonstrated two-dimensional and three-dimensional transfer of B35 neuronal cells onto and within polymerized Matrigel substrates, using matrix-assisted pulsed laser evaporation-direct write (MDW). The B35 cells were transferred from a quartz ribbon to depths of up to 75 microm by systematically varying the fluence emitted from the ArF (lambda = 193 nm) laser source. MDW-transferred cells were examined using terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL), 4',6-diamidino-2-phenylindole (DAPI), and alpha-tubulin staining. Confocal microscopy has shown that the transferred B35 cells extended their axons outward in three dimensions within the polymerized Matrigel substrate. The B35 cells made axonal connections and formed a three-dimensional neural network within 72 h after MDW transfer. In addition, TUNEL staining demonstrated that only 3% of the B35 cells underwent apoptosis after being transferred using the MDW process. MDW and other emergent direct write processes may provide unique approaches for creating layered, heterogeneous, three-dimensional cell-seeded scaffolds for use in peripheral nerve repair.

Effects of yogurt and bifidobacteria supplementation on the colonic microbiota in lactose-intolerant subjects

AIMS

Colonic metabolism of lactose may play a role in lactose intolerance. We investigated whether a 2-week supplementation of Bifidobacterium longum (in capsules) and a yogurt enriched with Bifidobacterium animalis could modify the composition and metabolic activities of the colonic microbiota in 11 Chinese lactose-intolerant subjects.

METHODS AND RESULTS

The numbers of total cells, total bacteria and the Eubacterium rectale/Clostridium coccoides group in faeces as measured with fluorescent in situ hybridization and the faecal beta-galactosidase activity increased significantly during supplementation. The number of Bifidobacterium showed a tendency to increase during and after supplementation. With PCR-denaturing gradient gel electrophoresis, in subjects in which B. animalis and B. longum were not detected before supplementation, both strains were present in faeces during supplementation, but disappeared after supplementation. The degree of lactose digestion in the small intestine and the oro-caecal transit time were not different before and after supplementation, whereas symptom scores after lactose challenge decreased after supplementation.

CONCLUSIONS

The results suggest that supplementation modifies the amount and metabolic activities of the colonic microbiota and alleviates symptoms in lactose-intolerant subjects. The changes in the colonic microbiota might be among the factors modified by the supplementation which lead to the alleviation of lactose intolerance.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides evidence for the possibility of managing lactose intolerance with dietary lactose (yogurt) and probiotics via modulating the colonic microbiota.

Five-year survival analysis of liver metastasis of colorectal cancer after hepatic resection

14571

Background: To evaluate the relation between hepatic resecion and survival rate of liver metastasis of colorectal cancer ( LMCC). Methods: Use retrograde case analysis method, 133 cases of LMCC received hepatic resection from 1/1/2000 to 31/12/2005 were included,with attention to the relation between hepatic resection and survival rate. Results: There were 133 cases underwent curative hepatic resection in all 470 LMCC cases, of which 30 cases (30/196,15.3%) in synchronous liver metastasis (SLM) group and 103 cases (103/274,37.6%) in metachronous liver metastasis (MLM) group, P<0.01. Mortality rate related to operation was 3.3%(1/30) in SLM and 1.9%(2/103) in MLM(P<0.05). Until 31/6/2006, all 133 cases were followed-up, 1,3,5 years survival rate and median survival time of SLM (81.0%, 40.3%, 16.5%, 22 months) is similar to that of MLM (88.2%, 49.1%, 31.7%, 25 months, P > 0.05), but the recurrence rate is higher(36.7% vs 20.4%,P=0.03). Compared to 49 cases whose liver metastases focus can be resected but chosen non- operative therapy, 1, 3, 5 years survival rate of 133 resected cases is higher (55.6%, 11.0%, 0 vs 86.2%, 39.2%, 29.4%, P=0.0034). In SLM, 22 cases received I stage resection of the primary colorectal tumor and liver metastasis and 8 cases received liver metastasis resection after the primary surgery (II stage operation). 1, 2, 3 years survival are 90.0% vs 87.5%(P > 0.05),61.4% vs 55.3%(P > 0.05)and 35.4% vs 30.0%(P > 0.05) and the median survival time is 28 months vs 26months(P > 0.05).COX multivariate analysis was used to analyze the prognositic factors. Incision margin =1cm(β=-0.8351,P=0.0363)and reoperation after recurrence(β=- 0.9428,P=0.0411)were protective survival factors, and postoperation recurrence (β=0.6471,P=0.0226) was survival risk factor. Conclusions: Curative hepatic resection is the first choice of liver metastasis of colorectal cancer and can improve survival.

No significant financial relationships to disclose.