Search for η

We measured missing mass spectrum of the ^{12}C(γ,p) reaction for the first time in coincidence with potential decay products from η^{'} bound nuclei. We tagged an (η+p) pair associated with the η^{'}N→ηN process in a nucleus. After applying kinematical selections to reduce backgrounds, no signal events were observed in the bound-state region. An upper limit of the signal cross section in the opening angle cosθ_{lab}^{ηp}<-0.9 was obtained to be 2.2 nb/sr at the 90% confidence level. It is compared with theoretical cross sections, whose normalization ambiguity is suppressed by measuring a quasifree η^{'} production rate. Our results indicate a small branching fraction of the η^{'}N→ηN process and/or a shallow η^{'}-nucleus potential.

Surgical shunt closure via the lumen of an intrahepatic portal aneurysm.

BACKGROUND/AIMS: A surgical shunt closure via the lumen of an intrahepatic portal aneurysm was successfully performed in a 70-year-old Japanese woman with hepatic encephalopathy due to hyperammonemia. She had a 4-month history of repeated hepatic encephalopathy which persisted after treatment with oral medicine. Color Doppler ultrasonography and computed tomography revealed a cystic peripheral portal aneurysm, 4 cm in diameter, connecting the posterior branch of the portal vein to the short hepatic vein in the right lobe. METHODS: While performing the Pringle maneuver and clamping the inferior vena cava below the liver, the wall of the portal aneurysm was opened, and the site of inflow from the portal vein and the site of outflow to the hepatic vein via the lumen of the portal aneurysm were closed with interrupted sutures. RESULTS: The patient's postoperative course was uneventful, and she was discharged 12 days after surgery. 12 months after surgery, she had no recurrence of hyperammonemia or hepatic encephalopathy. CONCLUSION: Surgical shunt closure via the lumen of a portal aneurysm can be performed safely, easily, and completely with good vision.

Effectiveness of systematized hepatectomy with Glisson's pedicle transection at the hepatic hilus for small nodular hepatocellular carcinoma: retrospective analysis.

BACKGROUND: The effectiveness of systematized hepatectomy with transection of Glisson's pedicle at the hepatic hilus in patients with small nodular hepatocellular carcinoma (HCC) has not been confirmed. METHODS: Surgical outcomes were reviewed in 204 patients with single nodular HCCs less than 5 cm in greatest diameter, including 68 patients with tumors that showed extranodular growth and 136 patients with tumors that did not, who had undergone curative hepatectomy (partial hepatic resection, n = 114; systematized hepatectomy, n = 90) from 1990 through 1994. RESULTS: The rates of microscopic vascular invasion and intrahepatic metastasis were significantly higher in patients who had single nodular HCCs with extranodular growth (34% and 49%) than in patients who had single nodular HCCs without extranodular growth (13%, P =.001, and 4%, P <.001). The 5-year survival rate in patients who had single nodular HCCs with extranodular growth was significantly greater after systematized hepatectomy (67%) than after partial hepatic resection (21%, P =.0002). Multivariate analysis showed that the type of operation was an independent prognostic factor in patients with single nodular HCCs with extranodular growth (P =.0008). CONCLUSIONS: Systematized hepatectomy with Glisson's pedicle transection at the hepatic hilus should be performed in patients who have single small nodular HCCs with extranodular growth because these tumors often invade within the liver sector containing the tumor.

Recurrence after surgical resection of intrahepatic cholangiocarcinoma.

We aimed to assess the patterns of recurrence after surgery for intrahepatic cholangiocarcinoma (ICC) and the outcomes of treatment in patients with recurrence. From 1981 to 1999, 123 patients with ICC underwent hepatectomy. The 3-year and 5-year survival rates were significantly higher in patients after curative resection (n = 56; 53%, 50%) than in patients after noncurative resection (n = 67; 7%, 2%; P < 0.0001). In 54 patients followed-up after curative resection, the rate of recurrence after surgery was 46%. The recurrences were in the liver (56%), abdomen (disseminated; 24%), and lymph nodes (20%). The rates of recurrence were significantly higher in patients with various classifications of mass-forming ICC tumors (P = 0.039) than in those with other types of tumors, and in patients with tumors over 3 cm in greatest diameter than in those with tumors 3 cm or less (P = 0.006). Hepatic recurrence, abdominal dissemination, and intraductal recurrence were significantly related to tumors that included mass-forming ICC (P = 0.002), tumors that included periductal infiltrating ICC (P = 0.009), and tumors that included intraductal growth ICC (P = 0.038), respectively. Seven patients with recurrence underwent radiation, chemotherapy, immunotherapy, or surgical resection. Only 2 patients, with intrahepatic metastasis and intraductal recurrence, respectively, had good outcomes after surgery. The effectiveness of other treatments has not been established.

CD9 is involved in invasion of human trophoblast-like choriocarcinoma cell line, BeWo cells.

The CD9 molecule is expressed on human extravillous trophoblasts, which invade the endometrium during implantation and placentation. To elucidate the role of CD9 in trophoblastic function, we investigated the expression of CD9 protein and mRNA in BeWo cells, a human trophoblast-like choriocarcinoma cell line, using immunohistochemistry, Western blotting and reverse transcription-polymerase chain reaction (RT-PCR). When BeWo cells were cultured with anti-CD9 monoclonal antibodies (mAb), their invasion through the extracellular matrices was significantly enhanced in a dose-dependent manner. Cell proliferation and human chorionic gonadotrophin production were unaffected. On the other hand, culture in the presence of mAb against integrins alpha3, alpha5 and beta1, which partially block the interaction with the extracellular matrices, inhibited BeWo cell invasion. Anti-CD9 monoclonal antibody had a stimulatory effect on BeWo cell invasion in the presence of anti-integrin alpha3 antibody. In contrast, it had no effect in the presence of mAb against integrins alpha5 and beta1, which were also highly expressed on BeWo cells. These findings suggest that CD9 has a function connected with the invasive properties of BeWo cells, which is partially mediated by integrin alpha5beta1. This may relate to the involvement of CD9 in trophoblastic invasion.

Initial phase of laser-induced air optical breakdown: a new picture.

Optical breakdown has been generated by focusing YAG laser radiation in the air. The laser radiation itself was scattered due to laser-induced air optical breakdown. Angular distributions of scattered radiation at 1064, 532, and 355 nm were measured. Analysis of the distributions has been performed in terms of Mie scattering. It has been assumed that scattering of laser radiation is due mainly to highly ionized plasma balls in the initial phase of air optical breakdown. The wavelength-dependent angular distribution has been analyzed with two parameters. The mean radius and the plasma frequency of the plasma balls have been determined by a least-squares fit procedure. Observed wavelength-dependent angular distributions are in good agreement with ones calculated by Mie theory.

Bcl-2 and Fas expression in eutopic and ectopic human endometrium during the menstrual cycle in relation to endometrial cell apoptosis.

OBJECTIVE: Our purpose was to investigate Bcl-2 and Fas expression in human eutopic and ectopic endometrium during the menstrual cycle in relation to endometrial cell apoptosis. STUDY DESIGN: Eutopic and ectopic endometrial samples were obtained from 29 patients with endometriosis, and eutopic endometrial tissue samples were obtained from 9 patients with uterine myoma. Bcl-2 and Fas expression were examined by immunohistochemical staining with specific monoclonal antibodies; Bcl-2 expression in eutopic endometrium was also examined by Western blotting and apoptotic cells were detected by the labeling of deoxyribonucleic acid fragments. RESULTS: In eutopic endometrium Bcl-2 was strongly expressed during the proliferative phase. Endometrial glandular cells showed evidence of cyclic changes in Bcl-2 expression, but cyclic changes were not apparent in peritoneal and ovarian endometriotic tissue. Fas expression was observed on glandular cells but not on stromal cells, and no cyclic changes in expression occurred in either ectopic or eutopic endometrium. Apoptotic cells were observed primarily in the glandular cells of the basal layer in eutopic endometrium during the late secretory and menstrual phases. CONCLUSION: The current study indicated that there was no apparent correlation between Bcl-2 or Fas expression with endometrial cell apoptosis. The absence of cyclic changes in Bcl-2 expression in ectopic endometrium implied a difference in the mechanisms of proliferation or differentiation between eutopic and ectopic endometrium.

Monoclonal antibody against phosphatidylserine inhibits in vitro human trophoblastic hormone production and invasion.

Naturally occurring antiphospholipid (aPL) antibodies against cardiolipin (CL)- and phosphatidylserine (PS)-dependent antigens are associated with placental dysfunction and unsuccessful pregnancy. Murine monoclonal aPL antibodies react with placental trophoblast and may interfere with normal trophoblastic function. In this study, we evaluated the expression of phospholipid-dependent antigens during trophoblast differentiation and measured the effects of monoclonal aPL antibodies on two in vitro aspects of trophoblast differentiation: hormone production and invasion into filters coated with extracellular matrix. Murine monoclonal IgM aPL antibodies that differentiated between PS and CL were used: 3SB9b reacted only with PS (CL-/PS+), D11A4 reacted only with CL (CL+/PS-), and BA3B5C4 reacted with both CL and PS (CL+/PS+). Isolated trophoblasts were cultured for 4 days, and reactivity with monoclonal aPL antibodies was evaluated daily. BA3B5C4 (CL+/PS+) reacted strongly with most trophoblasts that were freshly isolated (Day 0) and through 2 days of culture, after which time the percentage of cells reactive with BA3B5C4 decreased steadily. 3SB9b (CL-/PS+) reactivity increased during incubation; about 8% of cells reacted initially, but after 1 day of incubation 100% reacted, and this percentage remained stable throughout the 4-day incubation. D11A4 (CL+/PS-) reacted only minimally and at the level of the negative control monoclonal antibody (mAb) with 1- and 2-day cultures. Both mAbs that reacted with PS-dependent antigens completely prevented invasion of matrigel-coated filters by isolated trophoblasts. These mAbs also inhibited trophoblastic hCG and human PL production by more than 45%. Thus, as trophoblasts undergo differentiation, they are reactive with mAbs against PS. These antibodies are inhibitory in vitro to trophoblastic hormone production and invasion.

Progesterone stimulates the induction of human endometrial CD56+ lymphocytes in an in vitro culture system.

An unusual population of large granular lymphocytes (LGL) with the surface phenotype CD56(bright+)/CD16-/CD3- increases in the human endometrium during the late secretory phase and early pregnancy. To identify the factor(s) that induces CD56+ LGL in the human endometrium, we isolated endometrial leukocytes from nonpregnant human endometrium and investigated changes in CD56+ cells during culture with various factors. Isolated endometrial leukocyte-rich fraction and peripheral blood mononuclear cells were cultured for 6 days in the presence of progesterone, estradiol, PRL, or hCG, then nonadherent cells were collected and examined immunocytochemically. Endometrial leukocyte-rich fractions were composed of leukocytes and endometrial stromal cells, and 53.2 +/- 5.8% of them expressed CD45 antigen before culture. Therefore, leukocytes and endometrial stromal cells were cocultured in these endometrial leukocyte-rich fraction cultures. The percentage of CD56+ cells in endometrial leukocyte-rich fractions cultured with progesterone was significantly higher than that in fractions without progesterone. On the other hand, estradiol, PRL, and hCG did not significantly induce CD56+ cells in endometrial leukocyte-rich fractions. There was no significant difference in the percentage of CD56+ cells between peripheral blood mononuclear cell cultures with and without progesterone. These findings suggest that progesterone is an important factor for the in situ proliferation or differentiation of CD56+ LGL in human endometrium.

Endometrial stromal cell decidualization inhibits human chorionic gonadotrophin and human placental lactogen secretion by co-cultured trophoblasts.

We have developed an in-vitro co-culture system to examine the interaction between purified first trimester cytotrophoblasts and purified non-pregnant human endometrial stromal cells (ESC). ESC decidualization is an important step in endometrial maturation and may modulate embryo implantation. In order to investigate the effects of ESC decidualization on trophoblast function, we examined human chorionic gonadotrophin (HCG), human placental lactogen (HPL), progesterone and estrogen secretion by trophoblasts co-cultured in contact with ESC, either with or without decidualization induced by progesterone. Decidualized ESC inhibited basal HCG and HPL secretion for 3 days during the culture for HCG, and for 5 days during the culture for HPL (P < 0.01 and P < 0.03 respectively). After 5 days of co-culture, decidual transformation of ESC as indicated by prolactin production occurred in the control cultures due to progesterone and oestradiol secretion by the co-cultured trophoblasts, but no significant differences in HCG or HPL secretion were observed between the two groups. Although the type of trophoblast used in the present study is far from implantation, our results clearly demonstrated that HCG and HPL secretion by trophoblasts was inhibited by the presence of co-cultured decidualized ESC, and suggested that ESC decidualization may regulate trophoblast function at the human fetal-maternal interface.

Right side hepatic resection under right thoracoabdominal incision with special reference to a highly anatomical systematized method.

The results of 31 right side hepatic resections approached through thoracoabdominal incision are described, with emphasis on the benefit of the approach and systematized liver resection. Regarding postoperative mortality rate (0%) and morbidity rate (32.3%), the thoracoabdominal approach for right side hepatic resection seemed as safe and effective as the conventional abdominal approach. Even though there were no significant differences in the complications, the fluctuation of alanine aminotransferase and the hospital stay, the average operation time for the right segmentectomy through the thoracoabdominal approach was 1.3 hours less (p = 0.0078) than that of the abdominal approach. Technically, this approach was accomplished in almost the same fashion as in the abdominal approach by the utilization of systematized hepatic resection. Thoracotomy itself was not more harmful than the abdominal approach, even in patients with impaired liver function. This combination could take the advantage of a shorter operation time.

Monoclonal antiphosphatidylserine antibody reactivity against human first-trimester placental trophoblasts.

OBJECTIVE: To investigate the binding of antibodies against negatively charged phospholipids (antiphospholipid antibodies) to human placenta, we tested the reactivity of three mouse monoclonal antiphospholipid antibodies against first-trimester human placenta. STUDY DESIGN: Formalin-fixed and frozen sections of first-trimester placentas were stained by immunoperoxidase with three mouse monoclonal antibodies. Each monoclonal antibody reacted differently with cardiolipin and phosphatidylserine, 3SB9b reacted with phosphatidylserine, D11A4 reacted with cardiolipin, and BA3B5C4 reacted with both. RESULTS: 3SB9b reacted strongly with the syncytiotrophoblastic layer of both formalin-fixed and frozen placental tissue. Sporadic reactivity was observed against the cytotrophoblastic layer. BA3B5C4 reacted strongly and specifically with cytotrophoblastic cells. D11A4 reacted minimally or, more commonly, not at all. CONCLUSION: The trophoblastic layer directly in contact with the maternal circulation is most reactive with antiphospholipid antibodies that react with phosphatidylserine rather than cardiolipin, suggesting that the trophoblasts may potentially be directly damaged by antiphospholipid antibodies through mechanisms unrelated to thrombosis. In addition, the differential reactivity of 3SB9b and BA3B5C4 suggests that the antigenic conformation involving phosphatidylserine on the cytotrophoblast is altered concurrent with fusion into the syncytium.

Expression of phosphatidylserine-dependent antigens on the surface of differentiating BeWo human choriocarcinoma cells.

PROBLEM: Antiphospholipid antibodies (aPLs) are associated with pregnancy loss, pregnancy-induced hypertension, and intrauterine growth retardation. We have previously reported that phosphatidylserine (PS)-dependent antigens are expressed in formalin-fixed cells concurrent with differentiation in a choriocarcinoma model (BeWo) of cytotrophoblast. That study, however, could not differentiate between cytoplasmic or surface antigen expression. METHOD: Three monoclonal aPLs that differentiate between PS- and cardiolipin (CL)-dependent antigens were reacted with BeWo, with or without forskolin activation, before fixation, and antibody binding was evaluated by immunoperoxidase techniques. RESULTS: Activation with forskolin induced a PS-dependent antigenic determinant on the surface on BeWo cells. CL-reactive monoclonal antibodies did not react with the cell surface, whether forskolin treated or not. CONCLUSION: These observations demonstrate that a PS-dependent antigen is expressed on the surface of a model of differentiating cytotrophoblastic cells and should be accessible in vivo to circulating aPLs.

Tumour necrosis factor alpha inhibits in-vitro decidualization of human endometrial stromal cells.

Interleukin-1 (IL-1) has been reported previously to inhibit the in-vitro decidualization of human endometrial stromal cells as assessed by progesterone-induced prolactin production and morphological transformation. In this study we examined whether other cytokines, such as tumour necrosis factor-alpha (TNF alpha), interferon-beta (IFN beta), IFN gamma or granulocyte-macrophage colony-stimulating factor (GM-CSF), could affect the decidualization of human endometrial stromal cells in vitro. Of these cytokines, TNF alpha significantly suppressed prolactin production in a dose-dependent manner, with no apparent effect on cell number. The morphological transformation of endometrial stromal cells was also inhibited by TNF alpha. TNF alpha and IL-1 significantly suppressed cAMP-stimulated prolactin production by endometrial stromal cells. Neither the progesterone concentration in the supernatant of the endometrial stromal cell culture system nor intracellular calcium concentration of the endometrial stromal cells were affected by the addition of TNF alpha or IL-1. These results indicated that TNF alpha and IL-1 suppress both progesterone-induced and cAMP-mediated prolactin production in endometrial stromal cells, and that this inhibition was not attributable to direct effects on progesterone metabolism or related to Ca(2+)-mediated signal transduction. These experiments suggested that a local increase of TNF alpha and IL-1 under certain pathological conditions in vivo may disturb blastocyst implantation and/or the maintenance of pregnancy by inhibiting the decidualization of endometrial stromal cells.

Bestatin, a potent aminopeptidase-N inhibitor, inhibits in vitro decidualization of human endometrial stromal cells.

We have reported that human endometrial stromal cells (ESC) express a cluster of differentiation-13 antigen/aminopeptidase-N, and the expression of this peptidase antigen was shown to increase with the decidualization of ESC. To clarify the role of this peptidase in human endometrium, the effect of bestatin ([(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl]-(S)-leucine), an inhibitor of aminopeptidase-N, on the decidualization of ESC in vitro was examined. Purified human ESC were cultured for 12 days in the presence of 10(-6) mol/L progesterone with or without bestatin. Decidualization was assessed by PRL production and morphological transformation. The effects of a stereoisomer of bestatin and of pepstatin were similarly examined using the same culture system. Bestatin inhibited progesterone-induced PRL production in a dose-dependent manner, with no effect on cell number or viability, whereas neither its stereoisomer nor pepstatin inhibited aminopeptidase activity or PRL production. The morphological transformation of ESC was also inhibited by bestatin, but not by its stereoisomer or pepstatin. These findings demonstrate that the inhibition of aminopeptidase-N activity blocks the in vitro decidualization of ESC and suggest an important role for this peptidase in the functional differentiation of human ESC.