Carcinoembryonic antigen mRNA in abdominal cavity as a useful predictor of peritoneal recurrence of gastric cancer with serosal exposure

Peritoneal dissemination is the most frequent type of recurrence in patients with gastric cancer with serosal exposure, irrespective of whether they have undergone curative gastrectomy. The purpose of this study was to establish a method to detect micrometastatic cells in the abdominal cavity and predict peritoneal recurrence in patients with such gastric carcinomas. A total of 86 patients with gastric carcinoma, undergoing gastrectomy, were examined. Reverse transcriptase-polymerase chain reaction (RT-PCR) assay was used to detect carcinoembryonic antigen (CEA) mRNA in abdominal lavage fluid. Twenty-four cases without serosal exposure were negative, while all 13 cases with macroscopic peritoneal dissemination were positive for CEA mRNA. Among the 49 cases with macroscopic serosal invasion and without peritoneal metastasis, cancer cells were detected in 27 cases with RT-PCR while in only 6 cases with conventional cytology. All cytologically-positive cases were also positive for CEA mRNA. Among the 27 CEA-positive cases, 15 patients (56%) relapsed with peritoneal metastasis within 12 months after gastrectomy. In contrast, none of the 22 CEA-negative cases had peritoneal recurrence within 16-60 months of observation, whereas in 43 cytologically-negative cases, 10 patients relapsed with peritoneal recurrence. As compared with conventional cytological examination, this method would be clinically more beneficial for detecting free cancer cells in the peritoneal cavity and for predicting peritoneal recurrence in gastric carcinoma with serosal invasion.

Detection of matrix metalloproteinases in canine mammary tumours: analysis by immunohistochemistry and zymography

Expression of matrix metalloproteinases (MMPs) was examined immunohistochemically (MMP-9 and -2) and by gelatin zymography (MMP-9) in 12 benign and 12 malignant canine mammary tumours. In nine of 12 benign tumours, weak expression of MMP-9 was demonstrated immunohistochemically in the cytoplasm of neoplastic cells. In the remaining three benign tumours (mixed or complex) MMP-9 expression was observed in the neoplastic luminal epithelial cells and myoepithelial cells in some areas. The neoplastic luminal epithelial cells in 12 malignant tumours reacted strongly for MMP-9. MMP-2 immunolabelling was observed in both benign and malignant tumour tissues, but was stronger in the latter. Zymography and densitometry showed that expression of MMP-9 was higher in the benign mammary tumours than in normal canine mammary tissues, but highest in the malignant mammary tumours. In benign and malignant canine mammary tumours, the zymography and densitometry results for MMP-9 accorded well with the immunohistochemical results obtained with anti-human MMP-9 monoclonal antibody.

Classification of abomasal displacement in cows according to histopathology of the liver and clinical chemistry

Histopathological features of livers and blood chemical values in cows with abomasal displacement were investigated. Liver biopsy samples were collected during redressment operations in 92 cows with abomasal displacement, and the samples were stained with haematoxylin and eosin or periodic acid Schiff (PAS). Blood was collected for chemical tests. Livers were histopathologically divided into the following four types: normal histology cases (21%), fatty degeneration cases (36%), cloudy swelling cases (19%) and fatty degeneration cases with cloudy swelling (24%). The number of PAS-positive samples was significantly higher in the normal histology group and significantly lower in the severe fatty degeneration group and severe cloudy swelling group. Cows with fatty degeneration had significantly higher levels of serum 3-hydroxybutyric acid, non-esterified fatty acid and aspartate aminotransferase than did those with cloudy swelling or normal histology. The results indicate that the morbid conditions of cows with abomasal displacement can be classified into four types.

A case of estrogen-producing Brenner tumor with a stromal component as a potential source for estrogen

BACKGROUND

Although Brenner tumors with endocrine activities have been reported, the source or mechanisms for hormone production is poorly known at present.

CASE REPORT

A 66-year-old Japanese woman presented with atypical vaginal bleeding. A left ovarian tumor was detected on ultrasonography and CT scanning. Her serum estradiol level was elevated (73.5 pg/ml). We performed total hysterectomy, bilateral salpingo-oophorectomy and partial omentectomy. The ovarian tumor was diagnosed as a benign Brenner tumor associated with simple hyperplasia of the endometrium. Postoperatively, the serum estradiol level decreased. Immunoreactivity of cytochrome P-450 aromatase was detected in stromal cells.

CONCLUSION

Stromal contribution to the secretion of estrogen was shown in this case. Considering the known source of estrogen production being tumor cells in certain cases of Brenner tumor, there seem to be two types of estrogen-producing Brenner tumors depending on the source of estrogen, i.e. tumor cells or stromal cells.

Activation of the alternative complement pathway by Agaricus blazei Murill

Components of Agaricus blazei Murill have been demonstrated to have a wide range of immunopotentiating activities. The present study was designed to evaluate the effect of A. blazei Murill upon activation of the complement system in human serum in vitro. Additional studies were performed to determine the cytotoxic effect of complement-opsonized particles of A. blazei Murill against human tumor cells in culture. A fine particle of A. blazei Murill (ABP), prepared by mechanical disruption, was used throughout the experiments. ABP activated the human complement system via the alternative pathway in human serum. Activation of the alternative pathway was both time- and dose-dependent. When the particles from fruiting bodies of A. blazei Murill (ABP-F) were reacted with human serum, the formation of complement-opsonized ABP, iC3b-ABP-F complexes, and binding of the complexes to human peripheral blood monocytes, were demonstrated in vitro by immunofluorescence. Further, the resident human peripheral nucleated cells incubated in the presence of iC3b-ABP-F complexes inhibited the proliferation of human tumor cell line TPC-1 in vitro.

Quantification of minimal residual disease in patients with e1a2 BCR-ABL-positive acute lymphoblastic leukemia using a real-time RT-PCR assay

Using a real-time RT-PCR method, we analyzed the expression of e1a2 BCR-ABL mRNA in bone marrow samples from 13 patients with e1a2 BCR-ABL-positive acute lymphoblastic leukemia (ALL) at different time points during chemotherapy and after bone marrow transplantation (BMT). The detection limit of the method, assessed using serial dilutions of ALL/MIK cells, was found to be 1:10(5), similar to what is observed for the conventional RT-nested PCR method. The e1a2 BCR-ABL values were normalized with respect to those of the housekeeping gene GAPDH. The decrease in the e1a2 BCR-ABL/GAPDH ratio after remission induction chemotherapy reflects well the response to chemotherapy and consequently correlates with the prognosis. Although molecular remission was achieved by chemotherapy alone, some patients relapsed, and the e1a2 BCR-ABL/GAPDH ratios in these cases progressively increased to the levels seen prior to hematological relapse. Long-term hematological complete remission (more than 30 months) could be achieved in cases in which a more than 4.0 log decrease in the e1a2 BCR-ABL/GAPDH ratio was obtained by chemotherapy alone, and BMT was then performed. In conclusion, real-time RT-PCR allows for an evaluation of the kinetics of e1a2 BCR-ABL/GAPDH expression during the various phases of chemotherapy or after BMT and may be effective for the indication and control of disease relapse in Ph-positive ALL patients.

Dietary L-carnitine increases plasma insulin-like growth factor-I concentration in chicks fed a diet with adequate dietary protein level

1. The effect of L-carnitine supplemented into experimental diets with varying dietary protein concentrations (50, 200 and 400 g/kg) on body weight gain and plasma insulin-like growth factor-I (IGF-I) concentration in chicks was examined. 2. Dietary L-carnitine supplementation provided 0, 200, 500 and 1000 mg/kg. Chicks were given the diet ad libitum for 10 d. 3. When L-carnitine was provided as 500 or 1000 mg/kg, body weight gain was significantly improved in birds receiving the 200 and 400 g protein/kg diets. 4. There was an interaction between dietary L-carnitine and protein content on plasma IGF-I concentration. L-carnitine supplementation had little influence on plasma IGF-I concentrations in birds receiving the low protein (50 g/kg) diet. When dietary L-carnitine concentrations were increased from 0 to 1000 mg/kg in the adequate protein (200 g/kg) diet, plasma IGF-I concentrations were also increased. However, when dietary L-carnitine content was more than 500 mg/kg in the 400 g/kg protein group, plasma IGF-I concentration decreased with increasing dietary L-carnitine content. 5. Body weight change correlated significantly with the alteration in plasma IGF-I concentrations in chicks given diets with adequate dietary protein. 6. In conclusion, the improvement in body weight gain caused by dietary L-carnitine supplementation was achieved when chicks were given their dietary protein requirement, which may be partially explained by an increase in plasma IGF-I concentration.

Arsenic contamination in groundwater of Samta, Bangladesh

In March 1997, we analyzed the water of all tubewells used for drinking in Samta village in the Jessore district, Bangladesh. It has been confirmed from the survey that the arsenic contamination in Samta was one of the worst in the Ganges basin including West Bengal, India. 90% of the tubewells had arsenic concentrations above the Bangladesh standard of 0.05 mg/l. Tubewells with higher arsenic concentrations of over 0.50 mg/l were distributed in the southern area with a belt-like shape from east to west, and the distribution of arsenic concentration showed gradual decreasing toward northern area of the village. In order to examine the characteristics of the arsenic distribution in Samta, we have performed investigations such as: 1) the characteristics of groundwater flow, 2) the distribution of arsenic in the ground, 3) the concentration of arsenic and the other dissolved materials in groundwater, and 4) the distribution of arsenic concentration of trivalence and pentavalence. This paper examines the mechanism of arsenic release to groundwater and explains the above-mentioned characteristics of the arsenic contamination in Samta through the investigations of the survey results for these years.

Modulation of synaptic transmission in hippocampal CA1 neurons by a novel neurotoxin (beta-pompilidotoxin) derived from wasp venom

We examined the effects of beta-pompilidotoxin (beta-PMTX), a neurotoxin derived from wasp venom, on synaptic transmission in the mammalian central nervous system (CNS). Using hippocampal slice preparations of rodents, we made both extracellular and intracellular recordings from the CA1 pyramidal neurons in response to stimulation of the Schaffer collateral/commissural fibers. Application of 5-10 microM beta-PMTX enhanced excitatory postsynaptic potentials (EPSPs) but suppressed the fast component of the inhibitory postsynaptic potentials (IPSPs). In the presence of 10 microM bicuculline, beta-PMTX potentiated EPSPs that were composed of both non-NMDA and NMDA receptor-mediated potentials. Potentiation of EPSPs was originated by repetitive firings of the presynaptic axons, causing summation of EPSPs. In the presence of 10 microM CNQX and 50 microM APV, beta-PMTX suppressed GABA(A) receptor-mediated fast IPSPs but retained GABA(B) receptor-mediated slow IPSPs. Our results suggest that beta-PMTX facilitates excitatory synaptic transmission by a presynaptic mechanism and that it causes overexcitation followed by block of the activity of some population of interneurons which regulate the activity of GABA(A) receptors.

High expression of 92 kDa type IV collagenase (matrix metalloproteinase-9) in canine mammary adenocarcinoma

The 92 kDa type VI collagenase (matrix metalloproteinase-9 (MMP-9)) activities on zymography assay were found to be 1-6 times higher in benign tumor breast tissues of 12 canines and 4-26 times higher in adenocarcinoma breast tissues of nine canines than that of control tissues, respectively. A full-length canine MMP-9 cDNA was cloned from the adenocarcinoma tissue by reverse transcription-PCR and 5'- and 3'-RACE. The isolated cDNA contained an open reading frame coding for a polypeptide of 704 amino acids. The predicted protein sequence displayed extensive similarity to that of known MMP-9s and contained a putative signal sequence, a propeptide, an active site with three zinc-binding histidine residues, a calcium-binding domain, a hemopexin region, and three key cysteine residues. Western blotting using MMP-9-specific antibodies prepared against the peptide corresponding to Arg(642)-Asp(704) of canine MMP-9 and Northern blotting using a MMP-9-specific cDNA fragment as a probe confirmed that MMP-9 (the 92 kDa protein band) was highly expressed in canine mammary adenocarcinoma tissues. Higher levels of MMP-9 activity were found in the sera of canines with mammary adenocarcinoma. The results indicated that MMP-9 plays an important role in the progression of a canine mammary tumor and that assay of serum MMP-9 is helpful for early diagnosis as progress of adenocarcinoma.

Life-cycle toxicity of 4-nonylphenol to medaka (Oryzias latipes)

We studied the chronic effects of 4-nonylphenol (4-NP) on reproductive status of medaka (Oryzias latipes) over two generations of continuous exposure. The exposure study of the parental (F0) medaka was begun on embryos within 24 h postfertilization and continued with monitoring through embryological development, hatching, posthatch survival, growth, sexual differentiation, and reproduction under flow-through exposures to mean measured 4-NP concentrations of 4.2, 8.2, 17.7, 51.5, and 183 microg/L for up to 104 d. Eggs spawned from the F0 fish at 102 and 103 d posthatch were also examined for hatchability, survival after hatching, growth, and sexual differentiation until 60 d posthatch. The 183-microg/L treatment significantly reduced the embryo survival and swim-up success of the F0 fish. The cumulative mortality after swim-up of the F0 fish exposed to 17.7 and 51.5 microg/L were significantly higher than the control mortality. No concentration-related effect of 4-NP was observed on the growth of surviving F0 fish at 60 d posthatch. However, the sex ratio estimated from the appearance of their secondary sex characteristics was skewed toward female in the 51.5-microg/L treatment. Additionally, gonadal histology showed that 20% of the fish in the 17.7-microg/L treatment and 40% in the 51.5-microg/L treatment had testis-ova, indicating that 4-NP affects the gonadal development and survival of medaka at similar concentrations in juveniles. The sex ratio of the F0 fish in the 51.5-microg/L treatment was completely skewed toward female; subsequently, the effects on fecundity and fertility in this generation were monitored at mean measured concentrations of 4.2, 8.2, and 17.7 microg/L from 71 to 103 d posthatch. Fecundity was unaffected by any of the treatments examined. The mean fertility in the 17.7-microg/L treatment was reduced to 76% of that in the controls, although no statistically significant differences were determined. Overall, these results indicate that the lowest-observed-effect concentration (LOEC) and no-observed-effect concentration (NOEC) of 4-NP through the life cycle of the F0 medaka were 17.7 and 8.2 microg/L, respectively. In the F1 medaka, no significant effects were observed on hatching success, posthatch mortality, or growth, but sexual differentiation at 60 d posthatch was affected. Induction of testis-ova in the gonads of the F1 fish was observed in both the 8.2- and the 17.7-microg/L concentrations. The results indicate that 4-NP can have significant effects on reproductive potential of medaka at concentrations as low as 17.7 microg/L.

Birth of healthy twins from in vitro development of human refrozen embryos

OBJECTIVE

To avoid the risk of ovarian hyperstimulation syndrome and promote pregnancy rate by freezing pronuclear embryos at the oocyte retrieval and using developed refrozen supernumerary embryos in the event of failed pregnancies.

DESIGN

A case study.

SETTING

Private IVF center.

PATIENT(S)

Healthy infertile woman undergoing IVF treatment.

INTERVENTION(S)

Slowly frozen and rapidly refrozen embryos at varying stages of embryonic development were transferred.

MAIN OUTCOME MEASURE(S)

Survival rate of refrozen and thawed embryos; safety of refrozen embryo transference.

RESULT(S)

Fertilized pronuclear embryos that were frozen, thawed, and developed to morula embryos were subsequently vitrified, rethawed, and cultured until blastocyst formation before transfer. Healthy fraternal twins were born by caesarian section. The result of transfer was the novel finding of a successful delivery after the use of refrozen embryos.

CONCLUSION(S)

The transfer of refrozen supernumerary embryos resulted in successful pregnancy and delivery. We will continue to investigate the safety and efficacy of the elective freezing of all embryos as well as their refreezing so that supernumerary embryos can be reused to avoid ovarian hyperstimulation syndrome or in cases of repeated failed pregnancies.

Effects of CP-99, 994, a tachykinin NK(1) receptor antagonist, on abdominal afferent vagal activity in ferrets: evidence for involvement of NK(1) and 5-HT(3) receptors

The effect of CP-99, 994, a tachykinin NK(1) receptor antagonist, on abdominal vagal afferent nerve activity in the ferret was investigated. Substance P (1 microg/kg, i.v.) increased vagal afferent activity by 449.0+/-51.9% and this was reduced to 145.9+/-5.7% (p<0.01) by pre-treatment with CP-99, 994 (1 mg/kg, i.v.), and to 149.5+/-1.5% (p<0.001) by granisetron (1 mg/kg, i.v.), a 5-HT(3) receptor antagonist. In addition, the increase in vagal nerve activity induced by 5-HT (25 microg/kg, i.v., 552.0+/-57.0% increase from pre-injection level) was significantly reduced (401.3+/-10.6% increase from pre-injection level, p<0.05) by CP-99, 994 (100 microg/kg, i.v.). These results provide evidence for an involvement of peripheral NK(1) and 5-HT(3) receptors in substance P-induced vagal afferent activation. While the functional consequences (if any) of such peripheral effects were not investigated, they could contribute either directly (e.g. by blockade of receptors on vagal afferents) or indirectly (e.g. modulation of 5-HT release or reduction of local inflammatory response) to the antiemetic effects of CP-99, 994 against cisplatin and other emetic agents acting primarily via the vagus.

Spontaneous thoracic spinal cord herniation--case report

A 54-year-old female presented with spontaneous thoracic spinal cord herniation manifesting as chronic progressive motor weakness in both legs. Spastic paraparesis (4/5) and pathological reflexes such as ankle clonus were noted. She also had mild bladder dysfunction but no bowel dysfunction. She had no sensory disturbance, including tactile and pinprick sense. Magnetic resonance (MR) imaging revealed that the atrophic spinal cord was displaced into the ventral extradural space at the T4-5 intervertebral level with markedly dilated dorsal subarachnoid space. Computed tomography obtained after myelography showed no evidence of intradural spinal arachnoid cyst. She underwent surgical repair of the spinal cord herniation via laminectomy, and spinal cord herniation through the ventral dural defect was confirmed. Postoperative MR imaging revealed improvement of the spinal cord herniation, but her symptoms were not improved. Spontaneous spinal cord herniation is a rare cause of chronic myelopathy, occurring in the upper and mid-thoracic levels, and the spinal cord is usually herniated into the ventral extradural space. Early differential diagnosis from intradural spinal arachnoid cysts is important for a satisfactory outcome.

The application of three-dimensional internal structure microscopy in the observation of mare ovary

The ovary of the mare has a unique structure which differs totally from that of other mammals. However, because of its relatively large size, conventional histological techniques were unsuitable for the observation of the internal structure of the whole ovary. Three-dimensional internal structure microscopy (3D-ISM) consists of a cryotome-CCD camera-laser disc recorder-PC-based control system coupled with a graphic workstation. The internal structure of the ovary is observed by processing over more than 1,000 stored images of serially sliced surfaces of each frozen equine ovary. The 3D reconstruction was done using the full-coloured, volume-rendering method. The relationship between the localization of medulla, cortex and ovulation fossa was clarified. The ovulation fossa is localized in the centre of the ovary and is surrounded by a broad ovarian cortex. A trace of ovulation was observed only at the ovulation fossa. Medulla are localized in narrow peripheral areas. The phenomenon of the competition to occupy the cortical area ahead of the ovulation fossa by developing secondary follicles was visualized. Spatial localization of various sized follicles was identified from 3D-reconstructed images. In this study, it has been clarified that application or this novel computerized technique can clarify the anatomical arrangements of the equine ovary and the complex mechanism of equine follicular development.

The effect of flexural load cycling on the microleakage of cervical resin composites

Although several in vitro studies have attempted to investigate the microleakage of Class V resin composites under loading, the effect of load cycling on marginal seal is still unclear. This may be due to the fact that axial loads were applied to the specimens. This study investigated the effect of flexural loads on marginal sealing of cervical resin composites. One hundred and fifty cervical wedge-shaped cavities were restored with Clearfil Photo Bond, Clearfil Liner Bond 2, Scotchbond Multi-Purpose with 10% maleic acid, Scotchbond Multi-Purpose with 35% phosphoric acid or Mac-Bond 2 according to the manufacturers' instructions. After the restorations were finished, 10 specimens from each group were immersed in 0.5% basic fuchsin solution to examine microleakage. Prior to dye solution immersion, 20 specimens were subjected to flexural load cycling (1 mm labio-lingual or linguo-labial displacement at the incisal edge, 10,000 cycles, 1 cycle/second). The data were analyzed using the Kruskal-Wallis test and the Mann-Whitney U-test (p<0.05). When the flexural loads were not applied, both the incisal and apical margins showed good marginal sealing, regardless of the adhesive system used. Labio-lingual loading significantly deteriorated the marginal integrity at the incisal enamel margins, except for those restored with Clearfil Photo Bond. However, only Clearfil Photo Bond demonstrated a significant increase in microleakage along the apical dentin margins. Linguo-labial loading had no significant effect on the marginal seal.

Relationship between serum TNF activity and insulin resistance in dairy cows affected with naturally occurring fatty liver

To clarity the relationship between tumor necrosis factor (TNF) and insulin resistance in dairy cows affected with fatty liver, naturally occurring cases were investigated. The affected cows were classified into following three groups according to histopathologic findings of the liver: mild fat droplet deposition (group 1; n=11), severe fat droplet deposition (group 2; n=10), and cloudy swelling (group 3; n=8). Serum TNF activities in Group 2 (8.67 +/- 2.16 U/ml) and Group 3 (11.65 +/- 1.92 U/ml) were significantly higher than that in Group 1 (3.57 +/- 0.81 U/ml) (p<0.05). The insulin-tolerance tests showed that the insulin-stimulated glucose disposal rates (GDR) in Group 2 (27.6 +/- 7.8%) and Group 3 (15.8 +/- 9.1%) were significantly lower than that in Group 1 (41.7 +/- 9.8%). There was a significant negative correlation between serum TNF activity and GDR in affected cows (r=-0.56, p<0.01). These results indicate that serum TNF activity is correlated with insulin resistance in cows with fatty liver.

Bisphenol a glucuronide, a major metabolite in rat bile after liver perfusion

The environmental estrogen bisphenol A, orally introduced into the body, passes through the liver and modulates the endocrine system to elicit irreversible changes in the functioning of reproduction. To elucidate the actual and dynamic metabolism of bisphenol A in the liver before its arrival at target organs, this study evaluated the metabolism and disposition of the compound within the passage through the liver in Sprague-Dawley rats. On perfusion of 7.5 micromol of bisphenol A into the liver via the portal vein, approximately 91% of the infused bisphenol A was absorbed by the liver tissue, and about 65% of the absorbed bisphenol A was glucuronidated within 60 min. Roughly 65% of the bisphenol A glucuronide that formed in the liver was excreted into the bile and about 35% into the hepatic vein. On perfusion of 0.01, 0.05, and 0.1 mM bisphenol A solution into the liver, free bisphenol A was excreted only into the vein at 5.6, 9.3, and 14.6%, respectively, of the total bisphenol A. These results suggest that most bisphenol A absorbed by the intestine is probably glucuronidated exclusively in the liver and the conjugate is excreted mainly into the bile.

BeF(3)(-) acts as a phosphate analog in proteins phosphorylated on aspartate: structure of a BeF(3)(-) complex with phosphoserine phosphatase

Protein phosphoaspartate bonds play a variety of roles. In response regulator proteins of two-component signal transduction systems, phosphorylation of an aspartate residue is coupled to a change from an inactive to an active conformation. In phosphatases and mutases of the haloacid dehalogenase (HAD) superfamily, phosphoaspartate serves as an intermediate in phosphotransfer reactions, and in P-type ATPases, also members of the HAD family, it serves in the conversion of chemical energy to ion gradients. In each case, lability of the phosphoaspartate linkage has hampered a detailed study of the phosphorylated form. For response regulators, this difficulty was recently overcome with a phosphate analog, BeF(3)(-), which yields persistent complexes with the active site aspartate of their receiver domains. We now extend the application of this analog to a HAD superfamily member by solving at 1.5-A resolution the x-ray crystal structure of the complex of BeF(3)(-) with phosphoserine phosphatase (PSP) from Methanococcus jannaschii. The structure is comparable to that of a phosphoenzyme intermediate: BeF(3)(-) is bound to Asp-11 with the tetrahedral geometry of a phosphoryl group, is coordinated to Mg(2+), and is bound to residues surrounding the active site that are conserved in the HAD superfamily. Comparison of the active sites of BeF(3)(-) x PSP and BeF(3)(-) x CeY, a receiver domain/response regulator, reveals striking similarities that provide insights into the function not only of PSP but also of P-type ATPases. Our results indicate that use of BeF(3)(-) for structural studies of proteins that form phosphoaspartate linkages will extend well beyond response regulators.

Adsorption of endotoxins on glass in the presence of cationic proteins

Endotoxin activity was detected in empty glass tubes where endotoxins were incubated with lysozyme, histone or RNaseA, indicating adsorption of endotoxins on glass in the presence of cationic proteins. In the case of lysozyme, the recovery of spiked endotoxins (90.0%) using polystyrene tubes for incubation was much greater than the recovery (28.5%) using glass tubes, suggesting that lysozyme-mediated adsorption of endotoxins on glass is a major cause of poor recovery of spiked endotoxins in the LAL assay using glass tubes. In contrast, the recovery of spiked endotoxins (64.7%) using polystyrene tubes in the presence of the non-cationic protein BSA was less than the recovery (103.9%) using glass tubes. The difference in endotoxin recovery using glass or polystyrene tubes in the presence of cationic proteins or BSA can be explained by differences in protein adsorption on the tubes. Consequently, care must be exercised in selecting containers used for the LAL assay of proteins which bind to endotoxins.

Microleakage of self-etching primers after thermal and flexural load cycling

PURPOSE

To evaluate the adhesive properties of a one-bottle self-etching primer system.

MATERIALS AND METHODS

150 wedge-shaped cervical cavities on bovine teeth were restored with Clearfil Liner Bond 2 (LB), Clearfil Liner Bond 2V (LV) or Clearfil SE Bond (SE), according to the manufacturer's instructions. Twenty specimens of each adhesive system were finished 15 mins after light curing and 30 specimens were finished after a 24-hr storage period in water. From each group, 10 restorations were immediately immersed in 0.5% basic fuchsin solution and kept there for 24 hrs to examine microleakage. The other 10 restorations were thermocycled (5-60 degrees C, 15 s dwell time, 5,000 cycles), and then immersed in the dye solution. The remaining 10 specimens of the 24-hr storage group were subjected to flexural load cycling (0.5 mm labio-lingual displacement at the incisal edge, 10,000 cycles, 1 cps) prior to immersion in the dye solution. The data was analyzed using the Mann-Whitney U-test and the Kruskal-Wallis test. The tensile bond strengths of the adhesive systems to bovine enamel and dentin were also determined. The data was analyzed using the Student's t-test and ANOVA. In addition, SEM examinations were made to evaluate the effects of self-etching primers on enamel and dentin surfaces.

RESULTS

LV and SE showed significantly better marginal sealing than LB (P<0.05). The marginal integrity of SE did not deteriorate even after immediate finishing, thermal stresses or flexural loads. There were no significant differences in bond strengths among the adhesive systems tested. All adhesive systems showed similar bond strengths to enamel and dentin. The enamel etching patterns using LV and SE systems were obscure and difficult to assess. Although the smear plugs were not fully removed, no smear layer was observed on the treated dentin surfaces, regardless of the self-etching primer system used.

CLINICAL SIGNIFICANCE

Clearfil SE bond could possibly improve the clinical performance of cervical cavities.

Early relapse after high-dose chemotherapy rescued by tumor-free autologous peripheral blood stem cells in acute lymphoblastic leukemia: importance of monitoring for WT1-mRNA quantitatively

A 24-year-old woman who suffered from ALL with MLL gene rearrangement received high-dose chemotherapy followed by autologous PBSC transplantation during complete remission (CR). Reverse transcriptase-polymerase chain reaction (RT-PCR) used to detect MLL/LTG4 chimeric mRNA showed no minimal residual disease (MRD) in the graft or bone marrow at the transplantation. However, the leukemia relapsed four months after transplantation. Retrospective analysis of quantitative measurement of Wilms tumor gene (WT-1) mRNA showed an increased level in the bone marrow although it was within the normal range. These observations suggest that careful monitoring of MRD by quantitative measurement of WT-1 mRNA in addition to disease-specific chimeric mRNA is required to predict relapse.

Detection of abasic sites on individual DNA molecules using atomic force microscopy

We have developed an atomic force microscopy-based method for detecting abasic sites (AP sites) on individual DNA molecules. By using uracil and uracil DNA glycosylase, we first prepared a 250-bp DNA template consisting of two AP sites at specific locations. We then detected the AP sites by marking them with biotinylated aldehyde-reactive probes and monomeric avidin. We demonstrate here that (i) the location of monomeric avidin bound on a single DNA molecule was detectable by atomic force microscopy; (ii) the observed location of avidin was in good agreement to the predicted AP sites at a few nanometer resolution; and (iii) by end-labeling the 5'-terminus of one DNA strand, the AP sites were determined without directional ambiguity. The technique described here will provide a sensitive way of locating AP sites and contribute to screen DNA damages from individual molecules.

Birth of a healthy baby following vitrification of human blastocysts

OBJECTIVE

To assess vitrification of human blastocysts.

DESIGN

Retrospective study of blastocyst vitrification.

SETTING

A private clinic.

PATIENT(S)

Twenty couples with different types of infertility.

INTERVENTION(S)

Blastocysts were frozen with rapid vitrification and then transferred after thawing. We vitrified blastocysts using a modification of Ishimori's vitrification solution of ethylene glycol and dimethyl sulfoxide (VSED).

MAIN OUTCOME MEASURE(S)

After thawing, survival was defined by the embryo's development morphology after 6 hours or overnight culture.

RESULT(S)

Eighteen of 20 patients underwent treatment. Of 45 vitrified blastocysts, 36 survived, for a survival rate of 80% (36 of 45). The implantation rate was 21.9% (7 of 32), and the pregnancy rate (per embryo transfer cycle) was 33.3% (6 of 18). One of the pregnancies resulted in the delivery of a healthy baby.

CONCLUSION(S)

Supernumerary embryos were grown in culture to blastocysts, and the survival rate of vitrified-thawed blastocysts was the same as that for slow freezing of early stage embryos. Blastocyst vitrification should prove effective for clinical treatment. The present results strongly suggest that this rapid and successful vitrification procedure will replace conventional cryopreservation in the future.