Differentiation of mouse nuclear transfer embryonic stem cells into functional pancreatic beta cells

AIMS/HYPOTHESIS

Therapeutic cloning has been reported to have potential in the treatment of several degenerative diseases. However, it has yet to be determined whether mouse nuclear transfer-embryonic stem cells (NT-ESCs) can be differentiated into pancreatic beta cells and used to reverse diabetes in an animal model.

METHODS

We first used the somatic nuclear transfer technique to generate mouse NT-ESCs and then developed a chemically defined stepwise protocol to direct the NT-ESCs into functional pancreatic beta cells. We examined the gene expression pattern of the differentiated NT-ESCs and transplanted the NT-ESC-derived insulin-producing cells into recipient diabetic mice.

RESULTS

Four mouse NT-ESC lines were first established using an improved nuclear transfer technique and insulin-producing cells were efficiently generated from NT-ESCs by mimicking pancreatic in vivo development. Most of the insulin-producing cells that we generated co-produced pancreatic and duodenal homeobox 1, but not glucagon at the final stage of this differentiation method, which differed from the insulin and glucagon co-production reported by other groups. The differentiated NT-ESCs were able to release insulin in response to glucose stimuli and normalise the blood glucose level of diabetic mice for at least 2 months.

CONCLUSIONS/INTERPRETATION

These results demonstrate the potential of therapeutic cloning for cell therapy of type 1 diabetes in a mouse model.

Indomethacin improves locomotor deficit and reduces brain concentrations of neuroinhibitory steroids in rats following portacaval anastomosis

Hepatic encephalopathy (HE) is a neuropsychiatric complication of both acute and chronic liver failure characterized by progressive neuronal inhibition. Some neurosteroids are potent positive allosteric modulators of the gamma-aminobutyric acid (GABA)-A receptor complex, and 'increased GABAergic tone' has been proposed to explain the neuroinhibition characteristics of HE. Brain levels of the neurosteroids pregnenolone, allopregnanolone and tetrahydrodesoxycorticosterone (THDOC) and the functional status of the GABA-A receptor complex were assessed in rats following portacaval anastomosis (PCA). Effects of indomethacin, an inhibitor of the 3alpha-hydroxysteroid dehydrogenase enzyme involved in neurosteroid synthesis, on PCA rat locomotor activity and brain neurosteroid levels were also assessed. Significant increases of the neurosteroid pregnenolone (2.6-fold), allopregnanolone (1.7-fold) and THDOC (4.7-fold) were observed in brains of PCA rats. Brain levels of these neurosteroids were in the nanomolar range, sufficient to exert positive allosteric modulatory effects at the GABA-A receptor. Indomethacin (0.1-5 mg kg(-1)) ameliorated dose-dependently the locomotor deficit of PCA rats and concomitantly normalized brain levels of allopregnanolone and THDOC. Increased brain levels of neurosteroids with positive allosteric modulatory actions at the neuronal GABA-A receptor offer a cogent explanation for the notion of 'increased GABAergic tone' in HE. Pharmacological approaches using agents that either reduce neurosteroid synthesis or modulate the neurosteroid site on GABA-A receptor could offer new therapeutic tools for the management and treatment of HE.

Quetiapine facilitates oligodendrocyte development and prevents mice from myelin breakdown and behavioral changes

Recent neuroimaging and postmortem studies have reported abnormalities in white matter of schizophrenic brains, suggesting the involvement of oligodendrocytes in the etiopathology of schizophrenia. This view is being supported by gene microarray studies showing the downregulation of genes related to oligodendrocyte function and myelination in schizophrenic brain compared to control subjects. However, there is currently little information available on the response of oligodendrocytes to antipsychotic drugs (APDs), which could be invaluable for corroborating the oligodendrocyte hypothesis. In this study we found: (1) quetiapine (QUE, an atypical APD) treatment in conjunction with addition of growth factors increased the proliferation of neural progenitors isolated from the cerebral cortex of embryonic rats; (2) QUE directed the differentiation of neural progenitors to oligodendrocyte lineage through extracellular signal-related kinases; (3) addition of QUE increased the synthesis of myelin basic protein and facilitated myelination in rat embryonic cortical aggregate cultures; (4) chronic administration of QUE to C57BL/6 mice prevented cortical demyelination and concomitant spatial working memory impairment induced by cuprizone, a neurotoxin. These findings suggest a new neural mechanism of antipsychotic action of QUE, and help to establish a role for oligodendrocytes in the etiopathology and treatment of schizophrenia.

Functional characterization of interleukin-15 gene transduction into the human natural killer cell line NKL

BACKGROUND

Genetic modification of natural killer (NK) cells is a potential approach to gene-based immunotherapy of cancer. We created human interleukin-15 (hIL-15) gene-modified NKL cells and investigated their functional characterization in vitro.

METHODS

A recombinant vector (pcDNA3-IL15) or control vector (pcDNA3) was transferred into NKL cells by an electroporation method. Standard reverse transcriptase-polymerase chain reaction (RT-PCR), flow cytometry and MTT methods were performed for NK cell proliferation, apoptosis, cytotoxicity assays and gene expression tests.

RESULTS

Compared with parental NKL cells, hIL-15 gene modification promoted NK cell proliferation at low doses of IL-2 and inhibited cell apoptosis, which was associated with the up-regulation of anti-apoptosis genes Bcl-2, Bcl-xl and Mcl-1 as well as the down-regulation of apoptosis genes Bim and Noxa. Moreover, the anti-tumor activity of hIL-15 gene-transduced NKL cells against human hepatoma cancer cell line HepG2, H7402 and PLC/PRF-5 cells was enhanced, at least partly, through increasing expression of cytotoxicity-associated genes, including interferon (IFN)-gamma, perforin and FasL.

DISCUSSION

The hIL-15 genetic modification could improve the proliferation, anti-apoptosis and natural cytotoxicity of NKL cells against hepatocarcinoma cells. These data suggest that hIL-15 gene-modified NKL cells could be useful for clinical cancer immunotherapy in the future.

Identification of a novel HLA-A allele, HLA-A*9216

The new human leukocyte antigen (HLA)-A*9216 differs from A*02010101 by a nonsynonymous nucleotide change at condon 76 (GTG>CTG).

The efficacy of oxycodone for management of acute pain episodes in chronic neck pain patients

OBJECTIVE

Most treatments of acute pain associated with non-malignant chronic pains are not satisfactory. The aim of this study is to evaluate the efficacy and side effects of oxycondone controlled release (Oxy-CR) in managing chronic neck pain with acute pain episodes.

DESIGN

Randomised, double-blind, stand controlled study. A total of 116 patients were evenly divided into an oxycodone group (Oxy-CR, 5-10 mg and q12 h/day) and a placebo group (placebo, q12 h/day). Patients were assessed for the frequency of pain flares, visual analgesia score (VAS), quality of life (QOL), quality of sleep (QOS) and adverse effects before the treatment and on days 1, 3, 7, 14, 21 and 28 after the treatment. Withdrawal symptoms were monitored during the study, also on the completion of the entire study. The SF-36 was administered at the beginning and the end of the study for each patient.

RESULTS

Compared with the baselines of Oxy-CR and the placebo groups, the frequency of pain episodes and VAS were decreased significantly starting on day 3 of administration of Oxy-CR (p<0.05). Improvements in QOL and QOS were significant on day 3 after treatment with Oxy-CR (p<0.05). The patients who were treated with Oxy-CR reported significantly higher side effects than the patients in the placebo group (p<0.05). However, these side effects started to diminish after day 7 of the treatment. Withdrawal symptoms did not emerge in this study. Most domains of SF-36 were improved in the treated patients at the end of study (p<0.05).

CONCLUSION

Oxycondone controlled release could be an important optional drug for the management of refractory and frequent acute episodes of chronic neck pain in patients who failed to respond to non-opioid conservative treatment.

Beamlet deflection due to beamlet-beamlet interaction in a large-area multiaperture negative ion source for JT-60U

The JT-60U negative ion source has been designed to produce high current beams of 22 A through grids of 1080 apertures (five segments with nine rows of 24 apertures). One of the key issues is to steer such a high current beam through the multiaperture grids in order to focus the overall beam envelope because the beamlet-beamlet interaction may deflect the outer beamlets outward due to unbalanced space charge repulsion. To clarify the beam deflection in the JT-60U negative ion source, the beamlet trajectory in a multiaperture ion source was calculated by a three-dimensional simulation code. The measured angles of the outmost beamlets were in agreement with the calculated results where space charge of the beamlets was taken into account. It is noticed that the deflection of the outermost beamlet due to the beamlet-beamlet interaction is saturated at 5.2 mrad outward for beamlets more than ten.

Engraftment of adult porcine islet xenografts in diabetic nonhuman primates through targeting of costimulation pathways

Recent advances in human allogeneic islet transplantation have established beta-cell replacement therapy as a potentially viable treatment option for individuals afflicted with Type 1 diabetes. Two recent successes, one involving neonatal porcine islet xenografts transplanted into diabetic rhesus macaques treated with a costimulation blockade-based regimen and the other involving diabetic cynomolgus monkeys transplanted with adult porcine islet xenografts treated with an alternative multidrug immunosuppressive regimen have demonstrated the feasibility of porcine islet xenotransplantation in nonhuman primate models. In the current study, we assessed whether transplantation of adult porcine islet xenografts into pancreatectomized macaques, under the cover of a costimulation blockade-based immunosuppressive regimen (CD28 and CD154 blockade), could correct hyperglycemia. Our findings suggest that the adult porcine islets transplanted into rhesus macaques receiving a costimulation blockade-based regimen are not uniformly subject to hyperacute rejection, can engraft (2/5 recipients), and have the potential to provide sustained normoglycemia. These results provide further evidence to suggest that porcine islet xenotransplantation may be an attainable strategy to alleviate the islet supply crisis that is one of the principal obstacles to large-scale application of islet replacement therapy in the treatment of Type 1 diabetes.

A novel nude mice model of human extranodal nasal type NK/T-cell lymphoma

A novel nude mice model of human extranodal nasal type NK/T-cell lymphoma was established by subcutaneously implanting the sample taken from the patient with secondary extranodal nasal type NK/T-cell lymphoma of the stomach into the right axillary region of a BALB/c (nu/nu) nude mouse. This model had been successfully transplanted in vivo for thirty-two generations with a stable growth cycle. The survival rates of both resuscitation and transplantation were 100%. Histologically, the tumor cells were medium to large size and arranged in sheets, with a little mesenchyma, and disseminated almost in all passages of the lymphoma-bearing nude mice. Immunologically, the tumor cells were positive for CD56, cytoplasmic CD3, granzyme B or TIA-1 and LMP1, sometimes for CD8 but negative for surface CD3, CD7, CD20 and CD1a. EBER1/2 was found. No T-cell receptor gamma gene rearrangement was detected in the transplanted tumors. Furthermore, both human sequencing-tagged sites SY14 and Y chromosome were detected by PCR or fluorescent in situ hybridization, respectively, in the transplanted tumor. The transplanted tumor in this novel nude mice model maintained the essential features of human extranodal nasal type NK/T-cell lymphoma, and it would be an ideal tool in vivo for further research of the tumor.

HTERT mRNA expression correlates with matrix metalloproteinase-1 and vascular endothelial growth factor expression in human breast cancer: a correlative study using RT-PCR

BACKGROUND

Telomerase activity has been significantly associated with nodal metastasis and cellular proliferation in human breast cancer, indicating that its degree of expression has some form of vital control over the invasive nature of the malignancy concerned. Of the telomerase subunits, the reverse transcriptase (hTERT) is the main determinant of enzyme activity. Vascular endothelial growth factors (VEGF)-C and (VEGF)-D, matrix metalloprotease type 1 (MMP-1) and protease-activated receptors (PARs) have all been linked to promotion of tumour invasiveness and metastatic dissemination. This study aims to examine the association between hTERT transcription and that of VEGF-D, VEGF-C, MMP-1, PAR1a and PAR1b through a correlative analysis of the mRNA transcripts of these genes in human breast cancer.

MATERIALS AND METHODS

Breast cancer tissues (n = 116) and normal tissues (n-31) were collected immediately after surgery and stored at -80 degrees C until use. The level of hTERT transcripts from the prepared DNA from the above samples was determined using real time-quantitative PCR based on the Amplifluor technology. The levels of the transcript were generated from a standard that was simultaneously amplified with the samples. Normalisation against cytokeratin 19 (CK19) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was also carried out.

RESULTS

There was a positive correlation between hTERT mRNA expression (after CK19 normalisation) with both VEGF-D and MMP-1 in human breast cancer. PAR1 was seen to correlate with hTERT (after GAPDH normalisation) with a highly significant correlation with PAR1a alone. However there was no correlation between hTERT transcription and VEGF-C or with PAR1b alone.

CONCLUSION

Our findings suggest that hTERT is a potential up-regulator of MMP-1, PAR1 and VEGF-D expression and this may explain its apparent control over the invasiveness and metastasis of the malignancy concerned.

Phase II clinical trial of XELOX as first line treatment for patients with unresectable or metastatic gastric cancer

15062

Background: The survival of advanced gastric cancer remains poor, while no chemotherapy regimen was recognized standard. Oxaliplatin and Capecitabine (Xeloda) have demonstrated promising antitumor efficacy in advanced colorectal cancer. The present study was conducted to further evaluate the efficacy and safety of XELOX (Oxaliplatin and Xeloda) regimen in gastric cancer. Methods: Patients with unresectable or metastatic gastric cancer were enrolled into this study. They all receive the XELOX regimens (Oxaliplatin 130mg/ m2 intravenously in 2 hours on day 1 followed by oral capecitabine 1000mg/ m2 twice daily for 14 days every 3 weeks).We evaluated the response every 2 cycles. Results: The median age of the total enrolled 45 patients was 55 years (range, 22–82 years), including 32 male and 13 female. They received a median of 5 cycles (range, 2–8 cycles) of XELOX. 21 of 45 patients (46.7%) achieved an objective response, 1 patient (2.2%) had completed response. 17 patients (37.8%) experienced stable disease. Median time to tumor progression (TTP) and median overall survival were not available yet due to the further follow-up needed. Most toxicity events were mild to moderate in XELOX regimen, with grade 3/4 neutropenia of 8.9 %, thrombocytopenia of 6.7%, anemia of 11.1%, hand-foot syndrome of 6.7 % and diarrhea of 6.7 %. Grade 3 neuropathy was 4.4%. The patients with advanced gastric cancer had a good tolerance to this chemotherapy. Conclusions: XELOX is a highly effective first-line treatment for unrsectable and metastatic gastric cancer. The response rates in this trial seems to be similar to those observed with FU/leucovorin/oxaliplatin combinations. XELOX is tolerable well in the treatment of advanced gastric cancer.

No significant financial relationships to disclose.

Evaluation of outcomes before and after electronic medical record (EMR) and computerized physician order entry (CPOE) system implementation in an outpatient oncology setting

17058

Background: Computerized physician order entry (CPOE) in electronic medical records (EMR) has been recognized as an important tool in optimal health care provision that can reduce errors and improve safety. The objective of this study is to describe documentation completeness and user satisfaction of medical charts before and after outpatient oncology EMR/CPOE system implementation in a hospital based outpatient cancer center within three treatment sites and with sixteen physicians. Methods: A retrospective chart review was conducted on 32 randomly selected patients to date, who received one of the following regimens: FOLFOX, carboplatin-paclitaxel, CHOP-rituximab, or AC between 1999 and 2006. Charts were case matched with physician and regimen to compare documentation completeness. Completeness scores were assigned to each chart based on the number of documented data points found out of the 33 data points assessed. A user satisfaction survey of the paper chart and EMR/CPOE system was conducted among the physicians (n=16), nurses (n=43), and pharmacists (n=8) who worked with both systems. Results: The mean percentage of identified data points successfully found in the EMR/CPOE charts was 94% vs. 68% in the paper charts (p<0.001). Regimen complexity did not alter the number of data points found. The survey response rate was 64% and the results showed that satisfaction was statistically significant in favor of the EMR/CPOE system. The time required to find the data points will be assessed by having a physician, nurse, and pharmacist review the same charts. Data on 112 charts will be presented. Conclusions: Using EMR/CPOE systems improves completeness of medical record and chemotherapy order documentation and improves user satisfaction with the medical record system.

No significant financial relationships to disclose.

Pulsed wire discharge apparatus for mass production of copper nanopowders

A pulsed wire discharge (PWD) apparatus for the mass production of nanopowders has been developed. The apparatus has a continuous wire feeder, which is operated in synchronization with a discharging circuit. The apparatus is designed for operation at a maximum repetition rate of 1.4 Hz at a stored energy of 160 J. In the present study, Cu nanopowder was synthesized using the PWD apparatus and the performance of the apparatus was examined. Cu nanopowder of 2.0 g quantity was prepared in N(2) gas at 100 kPa for 90 s. The particle size distribution of the Cu nanopowder was analyzed by transmission electron microscopy and the mean surface diameter was determined to be 65 nm. The ratio of the production mass of the powder to input energy was 362 g/kW h.

32 Phase X 32 amplitude optical arbitrary waveform generation

We describe the precise shaping and mode-resolved amplitude and phase characterization of optical arbitrary waveforms by using a 20 GHz optical frequency comb and integrated 64 x 20 GHz channel arrayed waveguide grating pair. Complex waveforms with large variations in phase and amplitude between adjacent modes were generated and characterized.

Ultrastructural features of ichthyosis hystrix strongly resembling Lambert type

Ichthyosis hystrix (IH) is characterized by spiny hyperkeratotic scale, and includes Brocq type, Lambert type, Curth-Macklin type, Rheydt type and Bäfverstedt type. The first documented cases of familial IH were of Lambert type. However, the ultrastructural features of IH Lambert type have not been reported. Three patients in two generations of a family from north China were observed. The patients showed widespread verrucose lesions without blister formation. The face, palms and soles were unaffected. This presentation strongly resembled IH Lambert type. The lesions faded dramatically in summer, without treatment. Light microscopic examinations showed binuclear cells and shell formation in the granular and upper spinous layers in all specimens, with similar findings in winter, when lesions were prominent, and in summer, when lesions had subsided. Electron microscopic examination revealed binuclear keratinocytes and concentric, thin to thick, unbroken shells of tonofilaments surrounding the nuclei, and segregation of cytoplasmic components. This family is the first with familial IH strongly resembling Lambert type to be reported in China. Binuclear cells and tonofilaments shells surrounding the nucleus in upper keratinocytes were characteristic features, which were similar to those reported in IH Curth-Macklin type. The basic histopathological defects were not changed despite significant clinical improvement of the lesion.

Cyclooxygenase-2 inhibition: effects on tumour growth, cell cycling and lymphangiogenesis in a xenograft model of breast cancer

Cyclooxygenase-2 (COX-2) is associated with poor-prognosis breast cancer. We used a nude mouse xenograft model to determine the effects of COX-2 inhibition in breast cancer. Oestrogen receptor (ER)-positive MCF7/HER2-18 and ER-negative MDAMB231 breast cancer cell lines were injected into nude mice and allowed to form tumours. Mice then received either chow containing Celecoxib (a COX-2 inhibitor) or control and tumour growth measured. Tumour proliferation, apoptosis, COX-2, lymphangiogenesis and angiogenesis were assessed by immunohistochemistry (IHC), Western blotting or Q-PCR. Celecoxib inhibited median tumour growth in MCF7/HER2-18 (58.7%, P=0.029) and MDAMB231 (46.3%, P=0.0002) cell lines compared to control. Cyclooxygenase-2 expression decreased following Celecoxib treatment (MCF7/HER2-18 median control 65.3% vs treated 22.5%, P=0.0001). Celecoxib increased apoptosis in MCF7/HER2-18 tumours (TUNEL 0.52% control vs 0.73% treated, P=0.0004) via inactivation of AKT (median pAKT^ser473 57.3% control vs 35.5% treated, P=0.0001 – confirmed at Western blotting). Q-PCR demonstrated decreased podoplanin RNA (lymphangiogenesis marker) in the MCF7/HER2-18 – median 2.9 copies treated vs 66.6 control (P=0.05) and MDAMB231-treated groups – median 160.7 copies vs 0.05 control copies (P=0.015), confirmed at IHC. Cyclooxygenase-2 is associated with high levels of activated AKT^ser473 and lymphangiogenesis in breast cancer. Cyclooxygenase-2 inhibition decreases tumour growth, and may potentially decrease recurrence, by inactivating AKT and decreasing lymphangiogenesis.