D-Amino acid oxidase-induced oxidative stress, 3-bromopyruvate and citrate inhibit angiogenesis, exhibiting potent anticancer effects

Angiogenesis is critical for cancer growth and metastasis. Steps of angiogenesis are energy consuming, while vascular endothelial cells are highly glycolytic. Glioblastoma multiforme (GBM) is a highly vascular tumor and this enhances its aggressiveness. D-amino acid oxidase (DAO) is a promising therapeutic protein that induces oxidative stress upon acting on its substrates. Oxidative stress-energy depletion (OSED) therapy was recently reported (El Sayed et al., Cancer Gene Ther, 19, 1-18, 2012). OSED combines DAO-induced oxidative stress with energy depletion caused by glycolytic inhibitors such as 3-bromopyruvate (3BP), a hexokinase II inhibitor that depleted ATP in cancer cells and induced production of hydrogen peroxide. 3BP disturbs the Warburg effect and antagonizes effects of lactate and pyruvate (El Sayed et al., J Bioenerg Biomembr, 44, 61-79, 2012). Citrate is a natural organic acid capable of inhibiting glycolysis by targeting phosphofructokinase. Here, we report that DAO, 3BP and citrate significantly inhibited angiogenesis, decreased the number of vascular branching points and shortened the length of vascular tubules. OSED delayed the growth of C6/DAO glioma cells. 3BP combined with citrate delayed the growth of C6 glioma cells and decreased significantly the number and size of C6 glioma colonies in soft agar. Human GBM cells (U373MG) were resistant to chemotherapy e.g. cisplatin and cytosine arabinoside, while 3BP was effective in decreasing the viability and disturbing the morphology of U373MG cells.

[Influence of anesthesia procedure on malignant tumor outcome]

Malignant tumors are the second major cause of death in Germany. The essential therapy of operable cancer is surgical removal of primary tumors combined with adjuvant therapy. However, several consequences of surgery may promote metastasis, such as shedding of tumor cells into the circulation, decrease in tumor-induced antiangiogenesis factors, excessive release of growth factors for wound healing and suppression of immunity induced by surgical stress. In the last decade it has become clear that cell-mediated immunity controls the development of metastasis. Various perioperative factors, such as surgical stress, certain anesthetic and analgesic drugs and pain can suppress the patients' immune system perioperatively. On the other hand, by modifications of the anesthesia technique (e.g. regional anesthesia) and perioperative management to minimize immunosuppression, anesthesiologists can play a considerable role for a better outcome in patients having malignant tumors. Sufficient clinical evidence is not yet available to prove or disprove the hypothesis that anesthesia practice can improve cancer prognosis. Despite difficulties in study design, several prospective randomized trials are currently running and the results are awaited to elucidate this topic.

Histochemical localization of sialic acids and antimicrobial substances in eccrine glands of porcine snout skin

The distribution of sialic acids and antimicrobial products (lysozyme, IgA, lactoferrin, β-defensin 2) as well as Rab3D in the eccrine glands of porcine snout skin was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium consisted of two types of secretory cells: dark and clear cells. The dark cells exhibited considerable amounts of sialoglycoconjugates, which included O-acetylated sialic acids, whereas sialic acids in the sequence Siaα-2-3Gal1-4GlcNAc were confined to some of the dark cells. All antimicrobial substances and Rab3D were demonstrated to be also mainly present in some of the dark cells. Additionally, in the cytological and cytochemical features, the different characteristics were observed among the dark cells. The results obtained are discussed with regard to the functional significance of the eccrine glands. The secretory products elaborated by this gland type may function as protective agents in order to preserve the skin integrity of the snout region, considering that sialic acids and antimicrobial substances are important in general defense mechanisms.

V-cryo-plate procedure as an effective protocol for cryobanks: case study of mint cryopreservation

A vitrification procedure using aluminium cryo-plates (V-Cryo-plate procedure) was successfully developed and adjusted for in vitro-grown mint (Mentha spp.) shoot tips. Shoots were cultured at 25°C on MS medium containing 0.088 M sucrose for 7 to 14 days after the last subculture. Shoot tips with a basal part (1-1.5 mm × 1 mm) were dissected from the shoots and precultured at 25°C for 1 day on the same medium. Precultured shoot tips were placed on aluminium cryo-plates with 10 wells and embedded in alginate gel. Osmoprotection was performed by immersing the cryo-plates for 30 min at 25 degree C in 25 ml pipetting reservoirs filled with loading solution (2 M glycerol + 0.8 M sucrose). For dehydration, the cryo-plates were transferred and immersed in 25 ml pipetting reservoirs filled with PVS2 for 20 min at 25 degree C. Then the cryo-plates were transferred in uncapped 2 ml cryotubes and directly plunged into liquid nitrogen. For rewarming, shoot tips attached to the cryo-plates were immersed in cryotubes containing 2 ml 1 M sucrose solution at room temperature. Using this procedure, regrowth of cryopreserved shoot tips of line 'Fukuyamajisei' reached over 90 percent. This protocol was successfully applied to 16 additional Mentha lines, with regrowth ranging from 73 percent to 100 percent. This V-Cryo-plate method will facilitate the cryostorage of mint germplasm in our genebank.

Infective endocarditis with cerebrovascular complications: timing of surgical intervention

Management of infective endocarditis (IE) with cerebrovascular complications is difficult due to absence of concrete evidence. These patients usually have multiple neurological deficits and the optimal timing for cardiac operation remains controversial. The aims of this study were to present cases and discuss the treatment options for IE with cerebrovascular complications. From 1998 to 2010, 51 patients underwent operations for IE at our institution. From a review of medical records, 10 patients (19.6%) with preoperative neurological complications were identified. Data on these 10 patients were analysed. Cerebrovascular complications included cerebral infarction (n = 4, 40.0%), mycotic aneurysm (n = 1, 10.0%), mycotic aneurysm plus cerebral infarction (n = 3, 30.0%), meningitis (n = 1, 10.0%) and mycotic aneurysm with cerebral haemorrhage plus meningitis (n = 1, 10.0%). Of 5 patients having mycotic aneurysms, 3 underwent clipping before cardiac operations. The mean interval from craniotomy to cardiac operations was 26.7 ± 21.8 days. A cardiac operation was performed initially on seven patients. The mean interval from the onset of neurological deficit to cardiac operation was 7.4 ± 9.8 days. The mortality rate was 10.0%. Postoperative deterioration was not observed. Management of IE with cerebrovascular complications should be based on case-by-case multidisciplinary assessment of potential risks and benefits of intracranial and cardiac operations.

D-amino acid oxidase gene therapy sensitizes glioma cells to the antiglycolytic effect of 3-bromopyruvate

Glioma tumors are refractory to conventional treatment. Glioblastoma multiforme is the most aggressive type of primary brain tumors in humans. In this study, we introduce oxidative stress-energy depletion (OSED) therapy as a new suggested treatment for glioblastoma. OSED utilizes D-amino acid oxidase (DAO), which is a promising therapeutic protein that induces oxidative stress and apoptosis through generating hydrogen peroxide (H2O2). OSED combines DAO with 3-bromopyruvate (3BP), a hexokinase II (HK II) inhibitor that interferes with Warburg effect, a metabolic alteration of most tumor cells that is characterized by enhanced aerobic glycolysis. Our data revealed that 3BP induced depletion of energetic capabilities of glioma cells. 3BP induced H2O2 production as a novel mechanism of its action. C6 glioma transfected with DAO and treated with D-serine together with 3BP-sensitized glioma cells to 3BP and decreased markedly proliferation, clonogenic power and viability in a three-dimensional tumor model with lesser effect on normal astrocytes. DAO gene therapy using atelocollagen as an in vivo transfection agent proved effective in a glioma tumor model in Sprague-Dawley (SD) rats, especially after combination with 3BP. OSED treatment was safe and tolerable in SD rats. OSED therapy may be a promising therapeutic modality for glioma.

Improved outcome of surgical pulmonary embolectomy by aggressive intervention for critically ill patients

BACKGROUND

Acute massive pulmonary thromboembolism is a life-threatening disorder, and prompt treatment is necessary. We analyzed the outcome of pulmonary embolectomy for massive pulmonary embolism.

METHODS

Nineteen patients who underwent pulmonary embolectomy were retrospectively investigated. Average age of patients was 59 years, and 79% were female. Most patients had massive or submassive pulmonary thromboemboli dislodging into the main pulmonary trunk or bilateral main pulmonary arteries. Hemodynamics of most patients were unstable. Two patients required percutaneous cardiopulmonary support before embolectomy, and 4 required cardiopulmonary resuscitation. In 6 patients, thrombolysis was ineffective.

RESULTS

All patients underwent emergent pulmonary embolectomy. Operative mortality was 5.3%. No patients exhibited newly developed neurologic damage. Ten-year survival rate was 83.5% ± 8.7%.

CONCLUSIONS

Pulmonary embolectomy saves critically ill patients having acute massive pulmonary thromboembolism. We must evaluate pulmonary embolism patients with an algorithm that includes surgical embolectomy as one of several therapeutic options.

Development of the Very thin Microcrystalline N-Layer and its Application to the Stacked Solar Cell

In order to improve the efficiency of the amorphous silicon stacked solar cells, we have developed the preparation method of highly conductive very thin microcrystalline silicon n-layers. We have found that the addition of a small amount of Ar gas to deposition gases is effective to make microcrystallite size small. The obtained thin films were characterized by conductivity measurement, R-HEED observation and TEM observation.

This newly developed thin microcrystalline n-layers have been applied to the stacked solar cells. Increase of Jsc by 5-6% has been achieved because of the reduction of light absorption loss in n-layer without decrease of Voc and FF.

Continuous hemodiafiltration in children after cardiac surgery

Acute renal failure (ARF) after congenital cardiac surgery remains a serious complication and leading cause of morbidity and mortality. Continuous hemodiafiltration (CHDF) is presently accepted for pediatric applications. We retrospectively evaluated the effects of CHDF against ARF after congenital cardiac surgery at our hospital. We analyzed data from seven patients aged 23 days to 9 years and weighing 1.7-22.4 kg requiring dialysis therapy using CHDF after congenital cardiac surgery between April 2002 and January 2009. One patient who died could not be weaned from extracorporeal membrane oxygenation support and another died of multiple organ failure. Renal function recovered to normal in the other five (71%) patients. Treatment by CHDF lasted from 14 to 680 h and net ultrafiltration was 3.5 ± 1.4 mL/kg/h. Serum creatinine and urea concentrations were, respectively, 2.3 ± 1.6 and 43.7 ± 17.0 mg/dL before, and 0.5 ± 0.2 and 13.5 ± 8.1 mg/dL, after CHDF (P < 0.05). Thrombocytopenia developed in all patients, and platelet concentrates (0.76 ± 0.7 mL/kg/h) were infused during CHDF. Hypotension developed after changing the CHDF set in one patient. We suggest that CHDF is an effective alternative strategy for treating renal dysfunction after congenital cardiac surgery.

Corticostriatal functional connectivity in non-medicated patients with obsessive-compulsive disorder

The basal ganglia represents a key component of the pathophysiological model for obsessive-compulsive disorder (OCD). This brain region is part of several neural circuits, including the orbitofronto-striatal circuit and dorsolateral prefronto-striatal circuit. There are, however, no published studies investigating those circuits at a network level in non-medicated patients with OCD. Resting state functional magnetic resonance imaging scans were obtained from 20 non-medicated patients with OCD and 23 matched healthy volunteers. Voxelwise statistical parametric maps testing strength of functional connectivity of three striatal seed regions of interest (ROIs) with remaining brain regions were calculated and compared between groups. We performed additional correlation analyses between strength of connectivity and the severity scores for obsessive-compulsive symptoms, depression, and anxiety in the OCD group. Positive functional connectivity with the ventral striatum was significantly increased (P(corrected) < .05) in the orbitofrontal cortex, ventral medial prefrontal cortex and dorsal lateral prefrontal cortex of subjects with OCD. There was no significant correlation between measures of symptom severity and the strength of connectivity (P(uncorrected) < .001). This is the first study to investigate the corticostriatal connectivity in non-medicated patients with OCD. These findings provide the first direct evidence supporting a pathophysiological model involving basal ganglia circuitry in OCD.

Cloning, expression analysis, and regulatory mechanisms of bovine chemerin and chemerin receptor

Recently, we reported that chemerin, a new adipokine, is highly expressed in the adipose tissue, up-regulated during adipocyte differentiation, and regulates adipogenesis via its own receptor in mice. The objectives of this study were to clone chemerin and its receptor from the adipose tissues of Japanese Black cattle and to investigate the expression of these genes in 16 different tissues. We compared the gene expression of chemerin and its receptor between adipocytes and stromal-vascular (S-V) cells (non-adipocytes) prepared from subcutaneous adipose tissue. In addition, we investigated the mRNA expression levels of chemerin and its receptor in bovine differentiated adipocytes. The DNA sequences of bovine chemerin and its receptor were determined, and they were found to be highly homologous to those of humans, mice, and pigs. The amino acid sequences predicted for the full-length cDNA of bovine chemerin and its receptor were also similar to those of humans, mice, and pigs, suggesting that these genes have similar functions. Bovine chemerin mRNA was highly expressed in the adipose and liver tissues, and the transcripts of chemerin receptor were widely expressed in several tissues including adipose, muscle, liver, and brain tissues. The expression of bovine chemerin mRNA was higher in adipocytes than in S-V cells prepared from adipose tissue. The transcripts of chemerin and its receptor were up-regulated during adipocyte differentiation. Treatment with tumor necrosis factor (TNF)-alpha (10 ng/mL) in bovine differentiated adipocytes increased the mRNA expression of chemerin and its receptor. These results indicate that chemerin, a new adipokine highly expressed in the adipocytes of bovine adipose tissue, is the TNF-alpha-up-regulated gene with a role in adipogenesis.

Higher organization and histone modification of the plant nucleus and chromosome

Plants have a wide range of genome sizes. The length of each DNA molecule is usually much longer than the diameter of the cell and the length of each metaphase chromosome is effectively shortened to progress through mitosis. Thus some questions arise, such as: How is genomic DNA folded and shortened into chromosomes? What kind of proteins and/or their modifications contribute to chromosome structure? Are there any upper limits for the ratio of DNA volume to nuclear volume? This review attempts to answer these questions based on recent advances in chromosome research. Genomic DNA is first folded into nucleosomal fibers and then superfolded into metaphase chromosomes to sufficiently shorten its length to less than the upper limit for normal progression of cell division. Nucleosomes play structural roles, not only for DNA folding, but also for determination of euchromatin, heterochromatin, and centromeres, together with post-translational modifications and replacement of core histones with histone variants, and for the regulation of their structure and transcriptional status. More than 200 proteins of human metaphase chromosomes have been identified, including 5 types of nucleosome histones. They are categorized into 4 groups, and a 4-layer model of the human metaphase chromosome has been developed. There are upper limits for DNA volume. In all plants examined to date the DNA volume does not exceed 3% of the nuclear volume. Histone modification also has an impact on the spatial distribution of chromosomes within a nucleus, which seems to be related to the plant genome size. These points are discussed as well, as they are essential to maintain proper nuclear functions.

The effect of risperidone on D-amino acid oxidase activity as a hypothesis for a novel mechanism of action in the treatment of schizophrenia

D-Amino acid oxidase (DAO) has been established to be involved in the oxidation of D-serine, an allosteric activator of the N-methyl-D-aspartate-type glutamate receptor in the brain, and to be associated with the onset of schizophrenia. The effect of risperidone, a benzisoxazole derivative, atypical antischizophrenic drug, on the activity of human DAO was tested using an in-vitro oxygraph system and rat C6, stable C6 transformant cells overexpressing mouse DAO (designated as C6/DAO) and pig kidney epithelial cells (LLC-PK(1)). Risperidone has a hyperbolic mixed-type inhibition, designated as 'partial uncompetitive inhibition effect', with K(i) value of 41 microM on human DAO. Risperidone exhibited a protective effect from D-amino acid induced cell death in both C6/DAO and LLC-PK(1) cells with 10% increase in viability. These data indicate the involvement of DAO activity in D-serine metabolism and also suggest a new mechanism of action to risperidone as antischizophrenic drug.

Some Immunochemical Properties of Dextransucrase and Invertase from Streptococcus mutans

Dextransucrase and invertase of some strains of Streptococcus mutans were examined by immunodiffusion with antisera against enzymes purified from strain HS-6 (Bratthall's serotype a). Both antisera cross-reacted with crude enzyme preparations from the other serotype a (strains HS-1 and AHT) and d organisms (strains KIR, OMZ176, and OMZ65) but not with those from serotype b (strains FA-1 and BHT) or c organisms (strains GS-5, Ingbritt, and NCTC 10449). Based upon the antiserum used, the orders of antigenic similarity of the cross-reacting enzymes to the HS-6 enzymes were HS-6 > HS-1 > AHT = KIR = OMZ176 = OMZ65 for dextransucrase and HS-6 = HS-1 > AHT = KIR = OMZ176 = OMZ65 for invertase. It was found that the enzymes from serotype a organisms were not always antigenically homogeneous, as seen between strains HS-6, HS-1, or AHT for dextransucrase, and between the HS group and strain AHT for invertase. Antiserum against the HS-6 dextransucrase markedly inhibited the heterologous dextransucrases of serotype a organisms with the exception of strain HS-1 and d organisms, with or without the addition of dextran.