Safer Vitrification of Mouse and Human Embryos Using the Novel Cryoroom Vitrification System for Assisted Reproductive Technology.

BACKGROUND: Vitrification is widely used for assisted reproductive technology (ART). Most vitrification devices require the skillful placement of embryos into the carrier and aspiration of excessive vitrification solution. OBJECTIVE: To evaluate the efficacy and safety of the Cryoroom as a vitrification device. MATERIALS AND METHODS: Mouse and human embryos were vitrified with Cryoroom or Cryotop, and the developmental potency was assessed in vitro. Mouse monozygotic twin blastocysts were vitrified with Cryoroom or Cryotop for microarray analysis. RESULTS AND DISCUSSION: In mouse and human embryos, there were no differences between the survival and developmental progress in each device. In silico, the Cryoroom device showed no changes, particularly in DNA methylation after vitrification compared with the Cryotop. These results showed that the form and function of the device may affect the gene expression levels in vitrified embryos. CONCLUSION: The Cryoroom represents a safe and potentially revolutionary vitrification device for ART.

Identification of crude-oil components and microorganisms that cause souring under anaerobic conditions.

Oil souring has important implications with respect to energy resources. Understanding the physiology of the microorganisms that play a role and the biological mechanisms are both important for the maintenance of infrastructure and mitigation of corrosion processes. The objective of this study was to identify crude-oil components and microorganisms in oil-field water that contribute to crude-oil souring. To identify the crude-oil components and microorganisms that are responsible for anaerobic souring in oil reservoirs, biological conversion of crude-oil components under anaerobic conditions was investigated. Microorganisms in oil field water in Akita, Japan degraded alkanes and aromatics to volatile fatty acids (VFAs) under anaerobic conditions, and fermenting bacteria such as Fusibacter sp. were involved in VFA production. Aromatics such as toluene and ethylbenzene were degraded by sulfate-reducing bacteria (Desulfotignum sp.) via the fumarate-addition pathway and not only degradation of VFA but also degradation of aromatics by sulfate-reducing bacteria was the cause of souring. Naphthenic acid and 2,4-xylenol were not converted.

Identification of the domain required for trans-cleavage activity of hepatitis C viral serine proteinase.

A serine proteinase, Cpro-2, encoded in the hepatitis C virus (HCV) genome, is considered to be located in the N-terminal part of HCV p70, one of the putative nonstructural (NS) proteins of HCV. Cpro-2 is suggested to be responsible for producing several kinds of NS proteins by processing of the HCV precursor polyprotein. We identified the active domain of Cpro-2 and clarified the mechanism of HCV polyprotein processing; various HCV mutants deleted around this serine proteinase structure were cosynthesized with unprocessed HCV polypeptides containing Cpro-2-dependent cleavage sites in COS-1 cells. We showed that Cpro-2 cleaved the HCV precursor polyprotein intermolecularly (trans) and that Cpro-2 domain which is necessary and sufficient for that cleavage mapped to within 167 aa, from Gly1049 to Ser1215 of the HCV precursor polyprotein.

Processing of hepatitis C viral polyprotein in Escherichia coli.

Two proteinase activities, encoded by hepatitis C virus (HCV), Cpro-1 and Cpro-2. Cpro-1 and Cpro-2 appear to process the precursor polyprotein from which they originate. Mutant HCV polypeptides containing the region for these proteinases were produced in Escherichia coli as fusion proteins. The N- and C-terminal ends of the HCV polypeptides were fused with the E. coli maltose-binding protein (MBP) and E. coli dihydrofolate reductase (DHFR), respectively. The proteinase activities cleaved the fusion polypeptides by the same processing pathway used in eukaryotic protein production systems. The N-terminal amino acid (aa) sequences of the processed fusion proteins were determined. A comparison of those N-terminal sequences with the aa sequence of the HCV precursor polyprotein showed that the N-terminal and C-terminal cleavage sites of p70(NS3), one of the HCV nonstructural (NS) proteins, were the same as those identified in other processing studies: cleavages were estimated to be between aa 1026 and 1027 and between aa 1657 and 1658 of the HCV precursor protein, which are known to be cleaved by Cpro-1 and Cpro-2, respectively. Cpro-1 and Cpro-2 both functioned in E. coli and possessed authentic characteristic features.

Functional analysis of antibacterial activity of Bacillus amyloliquefaciens phage endolysin against Gram-negative bacteria.

To analyze the antibacterial activity of Bacillus amyloliquefaciens phage endolysin, nine deletion derivatives of the endolysin were constructed. Each deletion mutant was overexpressed, purified and characterized. The catalytic domain was located on the N-terminal region and the C-terminus had an affinity with the bacterial envelope. The enzymatic activity remained in spite of the deletion of the C-terminal 116-amino acid region; however, the antibacterial activity was lost. These results indicate that antibacterial action requires both the C-terminal cell-binding and the N-terminal enzymatic activities.

Association of genetic polymorphisms in CYP19 and CYP1A1 with the oestrogen receptor-positive breast cancer risk.

Since tamoxifen has been shown to reduce the risk of oestrogen receptor (ER)-positive, but not ER-negative, breast cancers in a chemoprevention trial (P-1), it is important to develop assays to assess risk factors for ER-positive breast cancer in order to appropriately select candidates for chemoprevention with tamoxifen. Thus, the significance of genetic polymorphisms of genes involved in oestrogen biosynthesis (CYP19) and metabolism (CYP1A1) as a risk factor for ER-positive breast cancers was evaluated. A case-control study was conducted with 257 breast cancer patients and 191 healthy female controls. Two polymorphisms, CYP19 (TTTA repeats) in intron 4 and CYP1A1 6235C/T in the 3' non-coding region, and their association with the breast cancer risk after adjustment for the other epidemiological risk factors were examined. CYP19 (TTTA)7(-3bp) allele carriers showed a significantly (P<0.05) increased risk of ER-positive breast cancers (Odds Ratio (OR)=1.72, 95% Confidence Interval (CI) 1.10-2.69), but not ER-negative breast cancers. CYP1A1 6235C allele carriers showed a non-significant (P=0.06) trend towards a decreased risk of ER-positive breast cancers (OR=0.65, 95% CI 0.42-1.02), but not ER-negative breast cancers. The combination of these two polymorphisms was found to be more useful in the assessment of the ER-positive breast cancer risk (OR=3.00, 95% CI=1.56-5.74) than the CYP19 (TTTA)7(-3bp) polymorphism alone. The combination of CYP19 (TTTA)7(-3bp) and CYP1A1 6235C/T polymorphisms is associated with an ER-positive, but not ER-negative, breast cancer risk, and, thus, would be useful in the selection of candidates for chemoprevention with tamoxifen.

Expression and processing of putative nonstructural proteins of hepatitis C virus in insect cells using baculovirus vector.

Processing of the putative nonstructural (NS) proteins, p70(NS3), p4(NS4A), p27(NS4B), p58/56(NS5A), and p66(NS5B), of Japanese type hepatitis C virus (HCV) in insect cells was analyzed by using a baculovirus expression system. Products processed by the HCV serine proteinase (Cpro-2) were essentially identical to those found in mammalian cultured cells transiently producing the NS region of the HCV precursor polyprotein. A series of internal and carboxy (C)-terminal deletion experiments coupled with epitope scanning analysis showed that efficient cleavage at the Cpro-2-dependent processing sites, except at the p4(NS4A)/p27(NS4B) site, is not significantly influenced by those mutations. Efficient cleavage at p4(NS4A)/p27(NS4B) required about 40% of the NS5A N-terminal region. Estimation of the processing sites by determination of the N-terminal amino acid sequences of the processed products revealed that all the Cpro-2-dependent cleavages occurred at essentially identical sites to those reported for another HCV genotype, suggesting that Cpro-2 is a possible target for the development of a strain-independent anti-HCV agent.

Successful treatment of refractory T-cell acute lymphoblastic leukemia by unmanipulated stem cell transplantation from an HLA 3-loci mismatched (haploidentical) sibling.

We describe a patient with refractory T-cell acute lymphoblastic leukemia who successfully underwent unmanipulated stem cell transplantation from an HLA 3-loci mismatched (haploidentical) sibling. In order to avoid severe graft-versus-host disease (GVHD), we used intensified GVHD prophylaxis consisting of tacrolimus, a short course of methotrexate, methylprednisolone, and mycophenolate mofetil. Hematopoietic reconstitution was rapid, with neutrophil count >5 x 10(8)/l on day +16, and platelet count >2 x 10(10)/l on day +25. There was no evidence of clinical acute GVHD. Bacterial, fungal, and viral infections were well controlled with antibiotics. The patient is still in complete remission past day +400. We suggest that unmanipulated HLA-mismatched transplantation with intensified GVHD prophylaxis is an alternative option for patients who do not have an HLA-identical donor.

Evidence for a novel Chlorella virus-encoded alginate lyase.

To clone the genes encoding lysis protein from a Chlorella virus, water samples were collected from 13 aquatic environments located in the Kanto area of Japan. Eight water samples contained plaque-forming viruses on Chlorella sp. NC64A, but no virus was detected in the other five samples. A novel Chlorella virus, CVN1, was isolated from the Inba-numa marsh sample. CVN1 genomic DNA was partially digested and shotgun cloned into pUC118 to identify the genomic region responsible for the lytic phenotype on Chlorella sp. NC64A. A DNA fragment which encoded two ORFs, ORF1 and ORF2, was obtained by antialgal assay. The ORF2 gene product, CL2, consisted of 333 amino acids showing antialgal activity not only on the original host of Chlorella sp. NC64A, but also on the heterogeneous hosts of Chlorella vulgaris C-27 and C. vulgaris C-207. CL2 showed a weak homology (19.8% amino acid identity) to mannuronate lyase SP2 from Turbo cornutus. CL2 in Escherichia coli cells was purified using a nickel chelate column. Lyase activity of purified CL2 on alginic acid was observed in an enzyme assay. The specific activity of purified CL2 was 2.1x10(-2) U mg(-1), the optimum pH for enzymatic activity was 10.5, and Ca(2+) was required for enzyme activity. This is the first report of a Chlorella virus protein with lyase activity.

The expression of urokinase type plasminogen activator is a novel prognostic factor in dukes B and C colorectal cancer.

Urokinase type plasminogen activator (u-PA) secreted by cancer cells is considered to play a key role in promoting invasion and metastasis of cancer cells. This study was designed to evaluate the expression and prognostic value of u-PA in Dukes B and C colorectal cancer. u-PA expression was investigated in 57 Dukes B or C colorectal cancers using a monoclonal antibody against u-PA. u-PA expression was mainly observed on the cytoplasm of cancer cells, and was associated with relapse, especially hematogenous metastasis (p=0.025, the chi2 test). Patients with high u-PA expression had a lower rate of DFS (9/22 events) compared to those with low u-PA expression (6/35 events) (p=0.061, log-rank test). This study demonstrated that u-PA expression might be a novel prognostic factor in Dukes B and C colorectal cancer.

Programmed Escherichia coli cell lysis by expression of cloned T4 phage lysis genes.

Self-disruptive Escherichia coli that produces foreign target protein was developed. E. coli was co-transformed with two vector plasmids, a target gene expression vector and a lysis gene expression vector. The lytic protein was produced after the expression of the target gene, resulting in simplification of the cell disruption process. In this study, the expression of cloned T4 phage gene e or t was used for the disruption of E. coli that produced beta-glucuronidase (GUS) as a model target protein. The expression of gene e did not lead to prompt cell disruption but weakened the cell wall. Resuspension with deionized water facilitated cell lysis, and GUS activity was observed in the resuspended liquid. Expression of gene e at mid logarithmic growth phase was the optimal induction period for GUS production and release. On the other hand, the expression of gene t induced immediate cell lysis, and intracellular GUS was released to the culture medium. Maximum GUS production was obtained when gene t was induced at late logarithmic growth phase.

Thrombomodulin is a new biological and prognostic marker for breast cancer: an immunohistochemical study.

BACKGROUND: Thrombomodulin (TM) is a natural anticoagulant which inhibits thrombin. Recent studies have reported that TM is correlated with vascular diseases and a few cancers. The aim of this study was to evaluate the role and the prognostic value of TM in breast cancer. PATIENTS AND METHODS: TM expression in samples from 60 invasive breast cancer patients was examined immunohistochemically with a polyclonal antibody against TM. RESULTS: TM staining was observed mainly on both the cytoplasm and cell surface in cancer cells and on endothelial cells around or in cancer tissue. TM expression in cancer cells was not correlated with the clinicopathological features. However, low TM expression was significantly correlated with a high relapse rate (p = 0.047 by the chi 2 test and 0.05 by the Kaplan-Meier method). CONCLUSIONS: TM might play an active role in cancer invasion and metastasis, and serve as a new prognostic factor in invasive breast cancer.

Urokinase type plasminogen activator receptor is a novel prognostic factor in breast cancer.

BACKGROUND: There have been many reports that the u-PA system plays an important role in cancer invasion and metastasis. The binding of u-PA to its specific cell-surface receptor, u-PAR, is necessary for the activation of u-PA system. The aim of this study is to evaluate the role and the prognostic value of u-PAR in cancer invasion and metastasis. PATIENTS AND METHODS: u-PAR expression in 104 breast cancers was investigated immunohistochemically using a monoclonal antibody against u-PAR. RESULTS: u-PAR expression was mainly observed both on cancer cells and stromal cells. Patients with high u-PAR expression in cancer cells or stromal cells had a high relapse rate compared with patients with low u-PAR expression by the Kaplan-Meier method (p = 0.035 and 0.011, respectively). In uni- and multivariate analysis, u-PAR expression in stromal cells was significantly correlated with relapse (p = 0.017 and 0.043, respectively). CONCLUSIONS: This study has shown that not only cancer cells but also stromal cells have an important roles in breast cancer invasion and metastasis, and that u-PAR expression in cancer cells and stromal cells might be a novel prognostic factor in breast cancer.

Possible involvement of calpain in the growth of estrogen receptor positive breast cancer cells.

Calpain (Ca2(+)-activated neutral protease, EC 3.4.22.17) has been reported to hydrolyze the estrogen receptor (ER). However, there has been no report available regarding the role of calpain in the growth of breast cancer cells. To investigate the role of calpain in the growth of various breast cancer cell lines, we employed a synthetic peptide, calpeptin, which is a cell permeable specific inhibitor of calpain. Calpeptin inhibited the cell growth of ER positive breast cancer cells, such as MCF-7, T-47D, and ZR-75-1 in a dose dependent manner in the presence of E2. However, the growth of ER negative breast cancer cells, MDA-MB-231, was not inhibited by calpeptin. It is suggested that calpain plays an important role in the growth of ER positive breast cancer cells.

Laparoscopic adrenalectomy: lateral transabdominal approach vs posterior retroperitoneal approach.

Laparoscopic adrenalectomy has been used to remove a wide variety of adrenal neoplasms. Although several laparoscopic approaches to the adrenal gland have been described, the lateral transabdominal approach has several advantages when compared with other approaches for laparoscopic adrenalectomy. From October 1995 to July 1999, we performed laparoscopic adrenalectomies on 16 patients, including eight posterior retroperitoneal approaches and eight lateral transabdominal approaches. Sixteen patients, ranging in age from 23 to 69 years, were treated for the following conditions: non-functioning adenoma, four patients; aldosteronoma, seven patients; pheochromocytoma, three patients; Cushing's adenoma, two patients. The average tumor size was 2.5 +/- 0.5 cm (1.8-3.0 cm, median 2.4 cm) in the lateral transabdominal approach, 1.2 +/- 0.8 cm (0.8-3.2 cm, median 1.75 cm) in the posterior retroperitoneal approach. Average operative time of lateral transabdominal approach was significantly shorter than that of the posterior retroperitoneal approaches (mean 129 min vs 269 min, P = 0.0005). Conversion to laparotomy was required in one patient in the posterior approach. Postoperative complication occurred in one pneumothorax in the lateral transabdominal approach and two subcutaneous emphysemas in the posterior retroperitoneal approach. There was no statistical difference in blood loss during the operation in the two groups. There was no mortality in either group. The lateral transabdominal approach is a safe and efficient technique for the removal of the adrenal neoplasms. Compared with other approaches, this technique has a wider working space and also good exposure for removing the adrenal gland.

Characterization of oxygen-dependent lysis of Escherichia coli cells infected by bacteriophage T4.

Infection of Escherichia coli cells by T4 phage at a multiplicity of infection (MOI) of 0.01 caused inhibition of cell lysis for up to 4 h. Such cells grown under aerobic condition were lysed by external stimuli such as cold shock, osmotic shock or addition of toxic substances, e.g., carbonyl cyanide m-chlorophenylhydrazone (CCCP). However, the effects of these external stimuli were reduced by transferring the cells to static incubation, by which dissolved oxygen was consumed by the cells within 10 min. The cells became insensitive to such external stimuli when the culture was deoxygenated with nitrogen gas. Following infection with a lysozyme amber mutant, eL1a, the cell membrane permeability was found to be increased either by cold shock or osmotic shock treatment of cells grown under aerobic conditions, but not in cells transferred to the static incubation. Oxygen limitation was suggested to enhance membrane stability in relation to cell lysis following the cold or osmotic shock treatment.

Cloning and expression of a gene encoding the lytic functions of Bacillus amyloliquefaciens phage: Evidence of an auxiliary lysis system.

A bacteriophage specific to Bacillus amyloliquefaciens, a gram-positive bacterium, was isolated from a local sewage treatment center. Using a lysis assay, a gene, lys1521, was isolated and its nucleotide sequence revealed one open reading frame of 375 bp. Homology studies showed amino acid alignment similarity with gene 5A of Bacillus subtilis phages PZA and phi29. Overexpression of the cloned gene yielded a 13 kDa protein corresponding to the predicted gene product. Despite the fact that no significant homology with known cell wall lytic enzymes was apparent, the lytic profile obtained in an in vivo expression assay showed that lys1521 had cell wall hydrolysis activity. This is a significant revelation since the function of the homologous gene 5A product of phage phi29 has been suggested to be required for the in vivo elongation of phage DNA replication. The lys1521 gene could be evidence of the presence in gram-positive bacteriophages of a third lysis gene in addition to the well characterized two-step lysis system.

Stimulating accumulation of nitrifying bacteria in porous carrier by addition of inorganic carbon in a continuous-flow fluidized bed wastewater treatment reactor.

Porous polyurethane carrier particles have been successfully applied for microbial immobilization to simultaneously remove carbonaceous and nitrogenous substances from wastewater by a fill-and-draw operation. This reactor system was extended to a continuous-flow operation mode, by which inorganic carbon (IC) was supplemented in order to stimulate the growth of autotrophic nitrifying bacteria. By addition of sodium bicarbonate, the ammonia oxidation reaction proceeded remarkably in the porous particle fluidized bed reactor, while a small increase in the nitrification was observed in a reactor with suspended microbes. Dissolved oxygen profile was obtained using an oxygen microelectrode to measure the microbial consumption of oxygen in the porous carrier. The size of ammonia-oxidizing bacterial populations in the carrier was proportional to the volume of the aerobic region of the carrier. The aerobic region decreased with the increase in sodium bicarbonate concentration, which improved the ammonia-oxidizing activity of retained nitrifiers in the carrier. The maximum ammonia oxidation rate was up to 55.6 gN/m3/h within the aerobic region of the carrier under the following feed conditions: 100 mg/l of total organic compound, 55 mg/l of ammonium concentration and 48 mg/l of inorganic carbon.

Enhanced microbial adaptation to p-nitrophenol using activated sludge retained in porous carrier particles and simultaneous removal of nitrite released from degradation of p-nitrophenol.

In order to examine the microbial degradation of p-nitrophenol (PNP) by a mixed culture system and simultaneous removal of nitrite released via the degradation, an activated sludge retained in porous carrier particles and a suspension culture as a control were acclimated to artificial sewage containing PNP as the sole carbon source. The adaptation of microbes retained in porous carrier particles to PNP was faster than that of suspended microbes by more than 20 d. After microbial adaptation to PNP, it was degraded completely without significant accumulation of intermediate metabolites. The PNP degradation activity of the retained microbes was more than 2 times higher than that of the suspended microbes. By increasing the retained microbial concentration, nitrite released from the degraded PNP was removed by denitrification. This research demonstrates that using microbes retained in porous carrier particles is not only effective for reduction of acclimation time but also enables simultaneous removal of the nitrogen compounds resulting from the degradation of nitroaromatics.

Structural analysis of a biofilm which enhances carbon steel corrosion in nutritionally poor aquatic environments.

Carbon steel coupons were exposed to nutritionally-poor synthetic wastewater inoculated with activated sludge from a municipal waste water plant. Biofilm formation was observed after one day incubation, and the thickness of the film increased proportionally with the incubation period. Mass loss of the coupons was also proportional to the incubation time, and reached 70.4 (mg/cm2) after incubation for 140 d. The observed mass loss was 5 times as much as that under sterile conditions. To characterize the microbiologically influenced corrosion (MIC) of carbon steel, structural analysis of the biofilm was performed. Rapid decrease in the dissolved oxygen (DO) concentration in the zone near the surface of the biofilm was observed by a microelectrode mounted on a micromanipulator. Heterogeneous distribution of the DO concentration on the surface of the steel plate was observed after multiple analyses. The heterogeneous structure of the biofilm composed of viable cells, inanimate objects, voids and pores was elucidated by confocal scanning laser microscopy. Concentrations of both aerobic bacteria and sulphur-reducing bacteria in the biofilm decreased with the incubation time, indicating that the increase in the biofilm thickness reflected an increase in the density of dead microbial cells or in extracellular polymer accumulation by the microbes. The average roughness of the metal surface observed after 112 d of incubation was +/-7.14 microm, which was 14.1% of the average thickness of the coupons. These observations indicated that uneven distribution of the DO profile and the cell concentration were critical for MIC of the carbon steel.