Identification of a functional luciferase gene in the non-luminous diurnal firefly, Lucidina biplagiata

We isolated a luciferase gene (LbLuc) from the non-luminous diurnal firefly, Lucidina biplagiata, with high similarity to that from the nocturnal firefly, Photinus pyralis. The recombinant LbLuc showed luminescence activity comparable to that of the luciferases from P. pyralis and Luciola cruciata. To understand the non-luminosity of L. biplagiata, we determined the amount of luciferase in the adult specimen using the luciferin-luciferase reaction and found that the content of luciferase in L. biplagiata was estimated to be only 0.1% of that in L. cruciata. As previously reported, the content of luciferin in L. biplagiata was less than 0.1% of that in L. cruciata. Thus, the non-luminosity of L. biplagiata might be explained by low levels of both luciferase and luciferin.

Improving chemotherapeutic drug penetration in melanoma by imatinib mesylate

BACKGROUND

Imatinib mesylate has specific activity in inhibiting select tyrosine kinase receptors, including platelet-derived growth factor receptors (PDGFRs) and c-kit. In general, melanomas widely express PDGFR and c-kit, and their in vivo resistance to chemotherapy is attributable to high tumor interstitial fluid pressure (IFP). Recent studies have suggested that PDGFR-beta inhibition reduces tumor IFP, and thus increases the uptake of concomitantly administered drugs.

OBJECTIVE

The present study was designed to investigate the potential of imatinib mesylate as a therapy for melanoma or as an adjuvant to chemotherapeutics.

METHODS

Using in vivo mouse models, the effect of imatinib mesylate on the growth of melanoma with or without dacarbazine was studied.

RESULTS

Imatinib mesylate enhanced the antitumor effect of dacarbazine on in vivo growth and lung metastases of melanoma cells, although treatment with only imatinib mesylate had no effect. We could detect perivascular expression of PDGF beta-receptor in melanoma tumors. Interestingly, dacarbazine uptake in melanoma was more than three-times increased by treatment with imatinib mesylate, while its uptake in serum or bone marrow was not affected by imatinib mesylate.

CONCLUSIONS

These data suggest interference with PDGF receptors, or their ligands, as a novel strategy to increase drug uptake and therapeutic effectiveness of chemotherapy for melanoma.

Identification of a subset of pericytes that respond to combination therapy targeting PDGF and VEGF signaling

The aim of our study was to further explore the use of anti-angiogenic therapy targeting the vascular endothelial growth factor receptor (VEGFR) on endothelial cells while simultaneously targeting platelet-derived growth factor receptors (PDGFRs) on adjacent pericytes. B16 mouse melanoma tumors exogenously expressing PDGF-BB (B16/PDGF-BB) display higher pericyte coverage on the vasculature compared to the parental B16 tumors (B16/mock). These models were used to investigate the effects of combination therapy targeting VEGFR and PDGFR signaling on size-matched tumors. Combination therapy using 25 mg/kg/day of the VEGFR inhibitor PTK787 and 100 mg/kg/day of the PDGFR inhibitor STI571 decreased the tumor growth rate of both tumor types, but the inhibition was only significant in the B16/PDGF-BB tumors. Combination therapy induced vessel remodeling, primarily by reducing the vessel density in B16/mock tumors, and by reducing the vessel size in B16/PDGF-BB tumors. When analyzing the effects of combination therapy on tumor vessel pericytes, it was found to primarily reduce the subpopulation of alpha-smooth muscle actin and PDGFRbeta-positive pericytes partly detached from the tumor vessels, without affecting the number of pericytes closely attached to the endothelium, which also express desmin. Taken together, these data demonstrate an increased benefit of targeting both VEGFR and PDGFR pathways in B16/PDGF-BB tumors, and demonstrates that the increased tumor growth inhibition in this model is accompanied by a reduction in a specific subset of pericytes, characterized by being loosely attached to endothelial cells and negative for the pericyte marker desmin.

Highly Active Antiretroviral Therapy Attenuates Re-Endothelialization and Alters Neointima Formation in the Rat Carotid Artery After Balloon Injury

Highly active antiretroviral therapy (HAART) has led to a sustained decline of HIV-associated morbidity and mortality. HAART exhibits significant side effects, however, such as hyperlipidemia and hyperglycemia, which possibly contribute to accelerated atherosclerosis in HAART-treated patients. In addition, direct effects of HAART on vascular cells have been described, which may promote atherosclerotic lesion formation. The effects of HAART on balloon-induced neointima formation have not been studied previously. The rat carotid artery balloon model was used to evaluate the effects of HAART (lopinavir, ritonavir, lamivudine, and zidovudine) on neointima formation and endothelial recovery. Furthermore, the effects of concomitant administration of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor rosuvastatin were investigated. HAART-treated animals displayed an increase in lesion size (neointima/media ratio: 1.14 +/- 0.32 vs. 1.31 +/- 0.20 in control vs. HAART; P < 0.05) and an impaired regenerative capacity of the endothelium, as indicated by reduction in endothelial regrowth from an adjacent undilated vessel segment 14 days after injury (re-endothelialization area: 8.29 +/- 1.45 mm vs. 5.09 +/- 0.53 mm in control vs. HAART; P < 0.05). When rosuvastatin was given in addition to HAART, these effects were not observed. In conclusion, HAART inhibited endothelial cell-mediated healing and promoted neointima formation after angioplasty in rats. These deleterious effects were attenuated by cotreatment with rosuvastatin, however. Our studies suggest that currently used drug regimens against HIV infection may lead to an increased risk for restenosis after percutaneous vascular interventions. Moreover, the findings indicate that the additional treatment with statins might counteract these adverse effects by HAART.

Platelet-derived growth factor production by B16 melanoma cells leads to increased pericyte abundance in tumors and an associated increase in tumor growth rate

Platelet-derived growth factor (PDGF) receptor signaling participates in different processes in solid tumors, including autocrine stimulation of tumor cell growth, recruitment of tumor stroma fibroblasts, and stimulation of tumor angiogenesis. In the present study, the B16 mouse melanoma tumor model was used to investigate the functional consequences of paracrine PDGF stimulation of host-derived cells. Production of PDGF-BB or PDGF-DD by tumor cells was associated with an increased tumor growth rate. Characterization of tumors revealed an increase in pericyte abundance in tumors derived from B16 cells producing PDGF-BB or PDGF-DD. The increased tumor growth rate associated with PDGF-DD production was not seen in mice expressing an attenuated PDGF beta-receptor and was thus dependent on host PDGF beta-receptor signaling. The increased pericyte abundance was not associated with an increased tumor vessel density. However, tumor cell apoptosis, but not proliferation, was reduced in tumors displaying PDGF-induced increased pericyte coverage. Our findings thus demonstrate that paracrine PDGF production stimulates pericyte recruitment to tumor vessels and suggest that pericyte abundance influences tumor cell apoptosis and tumor growth.

Lymphoid enhancer factor 1 makes cells resistant to transforming growth factor beta-induced repression of c-myc

The activation of lymphoid enhancer factor (LEF)/T-cell factor (TCF)-mediated transcription by sustained expression of beta-catenin and the loss of transforming growth factor beta (TGF-beta) signaling are essential steps in carcinogenesis, particularly for cancers of the colon, breast, and liver. The oncogene c-myc is a common target of both of these signaling pathways and a key regulator of cell cycle progression. Here we have identified a novel LEF/TCF-responsive element in the promoter of the human c-myc gene. beta-Catenin activated the transcriptional activity of the c-myc promoter by binding to this element in various cell lines. When TCF-4 was bound to this element, TGF-beta dissociated beta-catenin and repressed the transcriptional activity of the c-myc promoter. However, TGF-beta could not dissociate beta-catenin and could not repress c-myc transcription when LEF-1 was bound to the element instead of TCF-4. These findings suggest that enhanced expression of LEF-1, which occurs frequently in colon cancer, may make cells refractory to the down-regulation of c-myc and the subsequent growth arrest induced by TGF-beta.

A survey of vaginal hysterectomy ending in laparotomy

We did a retrospective study of 1,736 vaginal hysterectomies at Handa City Hospital from 1990 to 1999 with special reference to those 24 cases ending in laparotomy. The duration of operation, estimated blood loss, and uterine (with adnexal) weight of the failed vaginal hysterectomies were 139.1+/-42.9 min, 1,176.8+/-699.8 mL, 564.5+/-357.6 g, respectively. These values were significantly higher than those for the successful vaginal hysterectomies. Adhesions were seen in 14 cases (58.3%). Blood transfusion was required in 9 cases (37.5%). The most frequent cause for laparotomy was adhesions, followed by non-descent of the uterus. The decision to convert a vaginal hysterectomy into an abdominal procedure should be prompt because delay means the increased blood loss and a greater need for blood transfusions.

Successful pregnancy in a patient having high basal serum levels of sex steroid hormones

A 25-year-old infertile woman who had higher basal levels of serum progesterone (P) and estradiol (E(2)) was examined. Ultrasonography and gonadotropin-releasing hormone test suggested polycystic ovarian syndrome. The high serum E(2) and P concentration increased even more along follicle growth and after ovulation, respectively. Although the source of the higher levels of steroids was unclear, she became pregnant with artificial insemination of husband's sperm and luteal support with human chorionic gonadotropin administration, and delivered a healthy newborn. Through the present study, we can conclude that the high basal level of P in follicular phase may not always impair reproduction, although several reports stress that it adversely affects oocyte maturation and fertilization, and is harmful to endometrial receptivity.

Pregnancy following placental abruption

The aim of the present study by a retrospective chart review was to examine the recurrence rate after placental abruption. Between 1985 and 1998, 81 patients had a placental abruption. We had 2-year follow-up information about 31 patients and 27 of them had a total of 34 subsequent pregnancies. Recurrent placental abruption was observed in 6 pregnancies in 6 patients (6/27, 22.2%). Of the 6 recurrent placental abruptions, the gestational age was 1-3 weeks earlier than that of previous abruption in 4 patients. One patient delivered a healthy baby after her first abruption and then experienced a second abruption. We conclude that careful management is needed after 30 weeks in pregnant women with a previous history of placental abruption.

Fenofibrate improves insulin sensitivity in connection with intramuscular lipid content, muscle fatty acid-binding protein, and beta-oxidation in skeletal muscle

We investigated the effect of fenofibrate, a peroxisome proliferator-activated receptor-alpha agonist, on insulin sensitivity including lipid metabolism in skeletal muscle. Six-week-old male Sprague-Dawley rats were divided into two groups: those fed a standard chow (control) or a fructose-rich chow (fructose-fed rats (FFRs)) for 6 weeks. FFRs were treated either with a vehicle or with 30 mg/kg per day of fenofibrate for the last 2 weeks. Insulin sensitivity (M-value) was estimated by the euglycemic hyperinsulinemic glucose clamp method. Fatty acid-binding protein (FABP) in skeletal muscle was measured by ELISA, and the expression of FABP mRNA was analyzed by semi-quantitative RT-PCR. The serum and muscle triglyceride (sTG and mTG) levels and the activity of 3-hydroxyacyl-CoA dehydrogenase (HADH), a beta-oxidation enzyme, in muscle were also determined. FFRs showed a lower M-value and higher blood pressure, sTG and mTG than did the control group. The mTG was correlated positively with sTG and negatively with the M-value. Fenofibrate treatment for 2 weeks did not change blood pressure but significantly improved the M-value, sTG and mTG. FABP content and mRNA in the soleus muscle were significantly elevated in FFRs compared with those in the control group. Fenofibrate treatment further increased FABP. The HADH activity was comparable between the control group and FFRs, but significantly increased by fenofibrate treatment. These results suggest that fenofibrate improves insulin sensitivity not only by lowering serum lipids and subsequent influx of fatty acids into muscles but also by reducing intramuscular lipid content via further induction of FABP and stimulation of beta-oxidation in muscles.

Normal nephrogenesis occurs in the early stage of bilateral multicystic dysplastic kidneys

We present a case report about bilateral multicystic dysplastic kidneys (MCDKs). Pregnancy was terminated at 21 weeks' gestation and the fetus was examined by autopsy. The kidneys were replaced by many cysts and there was no parenchyma. However, on histological examination, there was normal nephrogenesis amid the cystic/dysplastic tissue. This suggests that normal nephrogenesis occurs before the secondary changes leading to MCDKs.

c-myc is a downstream target of the Smad pathway

c-Myc is one of the most potent regulators of cell cycle progression in higher eukaryotes. Down-regulation of c-Myc is a critical event for growth inhibition induced by transforming growth factor-beta (TGF-beta) and is frequently impaired in cancer cells. We determined a Smad-responsive element in the c-myc promoter. This element is a complex of the TGF-beta1 inhibitory element (TIE) originally identified in the transin/stromelysin promoter and an E2F site responsible for transcriptional activation of the c-myc promoter. Smad3 and E2F-4 directly bound to the element (TIE/E2F), and substitution of two nucleotides in TIE/E2F impaired binding of both Smad3 and E2F-4 as well as serum-induced activation and TGF-beta-induced suppression of the c-myc promoter activity. Smads bound TIE/E2F within 1 h after stimulation with TGF-beta, before the suppression of c-myc transcription, whereas binding of p130 to TIE/E2F became augmented later than 12 h. TGF-beta signaling did not compete with E2F-4 for binding to TIE/E2F, but reduced p300 co-immunoprecipitating with E2F-4. Therefore, TGF-beta signaling may suppress c-myc promoter activity by dissociating p300 from E2F-4.

Elevation of blood (1-->3)-beta-D-glucan concentrations in hemodialysis patients

Determination of the blood (1-->3)-beta-D-glucan (beta-DG) concentration is a sensitive marker to detect the presence of deep mycosis and fungal infections. Although cellulose material is known to contain beta-DG, the influence of a cellulose dialyzer membrane on the blood beta-DG level remains to be elucidated. In this study, we determined the plasma beta-DG levels in dialysis outpatients using either a modified regenerated cellulose (MRC) or a synthetic polysulfone (PS) membrane for more than 3 months. Plasma beta-DG levels were extremely high in patients using the MRC (2,778 +/- 549 pg/ml, n = 9) but not the PS membrane (18.8 +/- 3.7 pg/ml, n = 8) compared to normal ranges (<20 pg/ml). A single dialysis session using the MRC membrane further increased blood beta-DG values to 5,561 +/- 722 pg/ml (p < 0.01). After changing the membranes from MRC to PS, the blood beta-DG levels gradually decreased and reached 29.6 +/- 6.0 pg/ml at 6 months. In contrast, the PS membrane did not affect plasma beta-DG levels after a single dialysis session (16.0 +/- 3.9 pg/ml) or 4 months later (24.0 +/- 4.9 pg/ml). These findings suggested that a cellulose membrane could influence the measurement of blood beta-DG concentrations in the long-term. Careful assessment is required to diagnose the presence of fungal infection in HD patients using a cellulose membrane.

Psoas abscess with osteomyelitis in a patient undergoing long-term hemodialysis

We describe a 69-year-old male patient on maintenance hemodialysis for 24 years who developed a fatal left psoas abscess with osteomyelitis at the hip joint following acute enterocolitis. He had systemic beta(2)-microglobulin amyloid deposition in colon epithelium and psoas muscle. Cultures from abscess fluid and femoral bone marrow yielded Bacteroides fragilis. To our knowledge, this is the first case on hemodialysis having a psoas abscess following acute gastrointestinal infection. This rare case suggested that a secondary psoas abscess could be one of the occult infections in patients undergoing long-term maintenance hemodialysis.

High blood soluble receptor p80 for tumour necrosis factor-alpha is associated with erythropoietin resistance in haemodialysis patients

BACKGROUND

Inflammation is one of the major causes of resistance to erythropoietin (rHuEpo) treatment. Tumour necrosis factor-alpha (TNF-alpha), one of the most potent proinflammatory cytokines, is known to inhibit human erythropoiesis directly in vitro. Although blood levels of soluble receptors for TNF-alpha (sTNFRs) are elevated in haemodialysis (HD) patients, the role of sTNFR for rHuEpo responsiveness in HD patients remains to be clarified.

METHODS

We measured serum sTNFR (p55 and p80) levels in 83 stable outpatients undergoing regular HD (age 62+/-1, HD duration 15+/-1 years). After dividing the patients into three groups according to rHuEpo dose: (low (L) <60, n=31; moderate (M) > or =60 to <120, n=31; high (H) > or =120 U/kg/week rHuEpo, n=21), we examined the relationship between serum sTNFR levels and the degree of renal anaemia and rHuEpo dosage.

RESULTS

Haemoglobin was significantly higher in patients receiving low rHuEpo dosage (L, 10.5+/-0.2; M, 9.7+/-0.1; H, 9.5+/-0.2 g/dl, P<0.01 vs M and H groups). There were no differences in blood TNF-alpha, sTNFR p55, C-reactive protein, albumin, ferritin, or intact parathyroid hormone levels among the three groups. Body mass index and creatinine generation rate, a marker of whole-body muscle volume, were significantly reduced in group H (P<0.01). Serum sTNFR p80 levels were significantly higher in group H (4.88+/-0.45 ng/ml) than in L (3.73+/-0.14 ng/ml) and M (3.67+/-0.21 ng/ml) groups (P<0.05). The blood interleukin (IL)-6 level was also increased in patients requiring high rHuEpo doses (L, 5.5+/-0.5; M, 6.4+/-0.5; H, 10.2+/-2.0 pg/ml, P<0.05 vs L and H groups). A stepwise regression analysis revealed that gender and sTNFR p80 were significant predictors of rHuEpo dosage. A significant direct relationship was found between rHuEpo dose and sTNFR p80 (r=0.499) and IL-6 (r=0.439) values in women (P<0.01) but not in men.

CONCLUSIONS

These findings suggest that high blood sTNFR p80 may contribute to the development of rHuEpo resistance in female patients undergoing long-term HD.

Prevalence of asymptomatic ST segment elevation in right precordial leads with right bundle branch block (Brugada-type ST shift) among the general Japanese population

OBJECTIVE

To examine the modality and morbidity of asymptomatic ST segment elevation in leads V1 to V3 with right bundle branch block (Brugada-type ST shift).

METHODS

8612 Japanese subjects (5987 men and 2625 women, mean age 49.2 years) who underwent a health check up in 1997 were investigated. Those with Brugada-type ST shift underwent the following further examinations over a two year period after the initial check up: ECG, echocardiogram, 24 hour Holter monitoring, treadmill exercise testing, signal averaged ECG, and slow kinetic sodium channel blocker loading test (cibenzoline, 1.4 mg/kg).

RESULTS

Asymptomatic Brugada-type ST shift was found in 12 of 8612 (0.14%) subjects. Eleven of these 12 subjects were followed up. Follow up ECG exhibited persistent Brugada-type ST shift in seven of 11 (63.6%) subjects. ST shift was transformed from a saddle back to a coved type in three subjects. None of the subjects had morphological abnormalities or abnormal tachyarrhythmias. Positive late potentials were found in seven of 11 (63.6%) subjects. Augmentation of ST shift was shown by both submaximal exercise and drug administration in one of the 11 subjects (9.1%).

CONCLUSIONS

Asymptomatic subjects with Brugada-type ST shift were not unusual, at a rate of 0.14% in the general Japanese population. Almost all of the subjects had some abnormalities in non-invasive secondary examinations. Additional and prospective studies are needed to confirm the clinical significance and the prognosis of asymptomatic Brugada-type ST shift.

Prevalence of asymptomatic ST segment elevation in right precordial leads with right bundle branch block (Brugada-type ST shift) among the general Japanese population

OBJECTIVE

To examine the modality and morbidity of asymptomatic ST segment elevation in leads V1 to V3 with right bundle branch block (Brugada-type ST shift).

METHODS

8612 Japanese subjects (5987 men and 2625 women, mean age 49.2 years) who underwent a health check up in 1997 were investigated. Those with Brugada-type ST shift underwent the following further examinations over a two year period after the initial check up: ECG, echocardiogram, 24 hour Holter monitoring, treadmill exercise testing, signal averaged ECG, and slow kinetic sodium channel blocker loading test (cibenzoline, 1.4 mg/kg).

RESULTS

Asymptomatic Brugada-type ST shift was found in 12 of 8612 (0.14%) subjects. Eleven of these 12 subjects were followed up. Follow up ECG exhibited persistent Brugada-type ST shift in seven of 11 (63.6%) subjects. ST shift was transformed from a saddle back to a coved type in three subjects. None of the subjects had morphological abnormalities or abnormal tachyarrhythmias. Positive late potentials were found in seven of 11 (63.6%) subjects. Augmentation of ST shift was shown by both submaximal exercise and drug administration in one of the 11 subjects (9.1%).

CONCLUSIONS

Asymptomatic subjects with Brugada-type ST shift were not unusual, at a rate of 0.14% in the general Japanese population. Almost all of the subjects had some abnormalities in non-invasive secondary examinations. Additional and prospective studies are needed to confirm the clinical significance and the prognosis of asymptomatic Brugada-type ST shift.

Axin facilitates Smad3 activation in the transforming growth factor beta signaling pathway

Axin acts as a negative regulator in Wnt signaling through interaction with various molecules involved in this pathway, including beta-catenin, adenomatous polyposis coli, and glycogen synthase kinase 3beta. We show here that Axin also regulates the effects of Smad3 on the transforming growth factor beta (TGF-beta) signaling pathway. In the absence of activated TGF-beta receptors. Axin physically interacted with Smad3 through its C-terminal region located between the beta-catenin binding site and Dishevelled-homologous domain. An Axin homologue, Axil (also called conductin), also interacted with Smad3. In the absence of ligand stimulation, Axin was colocalized with Smad3 in the cytoplasm in vivo. Upon receptor activation, Smad3 was strongly phosphorylated by TGF-beta type I receptor (TbetaR-I) in the presence of Axin, and dissociated from TbetaR-I and Axin. Moreover, the transcriptional activity of TGF-beta was enhanced by Axin and repressed by an Axin mutant which is able to bind to Smad3. Axin may thus function as an adapter of Smad3, facilitating its activation by TGF-beta receptors for efficient TGF-beta signaling.

Polymethylmethacrylate efficacy in reduction of renal itching in hemodialysis patients: crossover study and role of tumor necrosis factor-alpha

Pruritus is one of the major unsolved problems for patients receiving regular hemodialysis. In this study, we conducted a 6 month prospective and crossover trial to investigate the effect of polymethylmethacrylate (PMMA) membrane for renal itching. We also examined the role of the tumor necrosis factor (TNF)-alpha system for pruritus in hemodialysis patients. We assessed the degree of skin itching and measured circulating levels of TNF-alpha and soluble TNF receptors (sTNFR-I, sTNFR-II) in 19 patients using hemodialysis, complicated by prolonged severe pruritus for 6 months. Serum sTNFR-I and II levels were significantly elevated in hemodialysis patients compared to normal subjects. Serum sTNFR-II levels were significantly and negatively correlated with serum albumin (r = -0.602, p = 0.007). A significant positive relationship was also found between sTNFR-I and erythropoietin dosage (r = 0.554, p = 0.016). However, no association was found between the degree of pruritus and circulating sTNFR-I and II values. Skin itching scale was significantly decreased from 2.7 +/- 0.2 to 2.1 +/- 0.3 following the use of PMMA membrane for 3 months (p < 0.05). In contrast, there was no change in itching scales during 3 months of conventional therapy (2.2 +/- 0.3 versus 2.2 +/- 0.3, p = NS). PMMA itself did not affect serum TNF-alpha and sTNFR values as well as conventional dialyzer membranes. These findings suggested that the PMMA dialyzer can improve renal itching not mediated through the modification of the TNF-alpha system.

Human chorionic gonadotropin beta-core fragment is directly produced by cancer cells

The present study was undertaken to investigate whether hCG beta-core fragment (hCGbeta cf) was directly produced by cancer cells. Fifteen cell lines, including four choriocarcinoma and five ovarian cancer cell lines, were tested, and immunoreactivity of hCGbeta cf was present in the culture media of five of the cell lines. It was also present in the culture media of Chinese hamster ovary (CHO) cells transfected with hCGbeta gene. In addition to hCGbeta cf, gel chromatography and Western blot analysis of the culture media showed the presence of an hCGbeta cf immunoreactive material with a molecular weight of approximately 40 kDa. In an in vivo study, hCGbeta cf immunoreactivity was detected in the sera of the mice transplanted with NaUCC-3 choriocarcinoma cells, although the ratios of hCGbeta cf/hCG and hCGbeta cf/free hCGbeta were lower than those in the culture medium. Incubation experiments of purified hCGbeta cf in the serum showed no substantial decrease in its values, ruling out the possibility that formation of a macromolecule with serum components may mask hCGbeta cf immunoreactivity in the serum. Taken together, these results indicate that hCGbeta cf immunoreactive materials are directly produced by cancer cells and hCGbeta cf is not a urinary metabolite of hCG or hCGbeta alone. Also, reduced levels of hCGbeta cf in the serum compared with that of intact hCG or free hCGbeta are likely due to its short half-life.

Human chorionic gonadotropin beta-subunit affects the folding and glycosylation of alpha-cys mutants

Human chorionic gonadotropin (hCG) is a member of a family of heterodimeric glycoprotein hormones that contain a common alpha-subunit but differ in their hormone-specific beta-subunits. Both subunits have five and six disulfide bonds, respectively, which consist of cystine knot structure. It is evident from numerous studies that the structure of beta-subunits is rigid, whereas that of alpha-subunit is flexible and can be molded by a beta-subunit. Previously, we reported that secreted forms of a mutants where either cysteine residue in the disulfide bond 7-31 or 59-87 was converted to alanine contained a disulfide-linked homodimer in addition to a monomer. To study whether the hCGbeta-subunit affects the conformations of alpha mutants, alpha-subunits lacking either the 7-31 or 59-87 disulfide bond were expressed with wild-type (WT) hCGbeta in Chinese hamster ovary cells, and homodimer formation and glycosylation of dimerized alpha-subunit were assessed by continuous labeling with [35S]methionine/cysteine, immunoprecipitation with anti-alpha or -hCGbeta serum, digestion with endoglycosidase-H or -F, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in a non-reducing condition. Our data showed that a homodimer was not observed in the half-Cys mutants except one, where cysteine at position 7 was converted to alanine, in the presence of beta-subunit. This finding indicated that hCGbeta-subunit rescued the a half-Cys mutants from the formation of intermolecular disulfide-linked homodimer by preferentially combining with the alpha mutants. In both free WT and all mutants treated with endoglycosidase-H, no or faint bands were recognized as the same migration as seen in endoglycosidase-F treatment. Even in the endoglycosidase-H sensitive cases, the amount of sensitive alpha-subunits was less than 5% of total alpha-subunits. In contrast to free alpha-subunits, distinct endoglycosidase-H sensitive bands were seen in both WT and mutants, although the ratio was various. We concluded that hCGbeta-subunit affects the folding and glycosylation of the alpha-subunit mutants.

Hydrops of placental stem villi complicated with fetal congenital adrenal hyperplasia

The authors present a case report of hydrops of placental stem villi. Numerous small aechoic spaces were demonstrated by prenatal ultrasonography. The patient spontaneously delivered a female newborn at 26 weeks' gestation. The infant showed hypertrophied clitoris and urogenital sius, and had a normal 46, XX karyotype. Endocrinological examination revealed that 3beta-hydroxysteroid dehydrogenase deficiency caused the anomaly. To our knowledge, this is the first report that congenital genital malformation complicated the placental mesenchymal dysplasia.

Adenomyomatous polyp mimicking hydatidiform mole on ultrasonography

The authors present a case report of a 62-year-old woman who experienced irregular genital bleeding. Although the serum hCG level was extremely low, transvaginal ultrasonography revealed vesicle pattern in the uterine cavity, suggesting trophoblastic disease. Hysterectomy was performed and histological diagnosis was adenomyomatous polyp. To our knowledge, this is the first report that the adnomyomatous polyp can demonstrate the vesicle pattern on ultrasonography.

Additional N-glycosylation at Asn(13) rescues the human LHbeta-subunit from disulfide-linked aggregation

CG, LH, FSH, and TSH are a family of heterodimeric glycoprotein hormones that contain a common alpha-subunit, but differ in their hormone-specific beta-subunits. Despite the considerable homology between LHbeta and CGbeta, we previously demonstrated that, when expressed in GH(3) cells, the secreted form of LHbeta showed mispaired disulfide-linked aggregation in addition to monomer, whereas no aggregation was observed in CGbeta. To determine the domains which are associated with the LHbeta-aggregation and which prevent CGbeta-aggregation, mutant beta-subunits in glycosylation and carboxy-terminus were expressed in GH(3) cells, and the occurrence of aggregation was assessed by continuous labeling with [35S]methionine/cysteine, immunoprecipitation with anti-hCGbeta serum, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in a non-reducing condition. No aggregation was seen when N-linked oligosaccharides were attached to the Asn(13) of LHbeta. Removal of the carbohydrate unit at the Asn(13) of CGbeta caused aggregation, although the amount was less than 10% of monomer. The carboxy-terminal regions of neither LHbeta nor CGbeta were associated with their aggregation. Both CGbeta wild-type (WT) and CGbeta lacking N-glycosylation at Asn(13) (CGbeta-N13) showed aggregates in lysate. However, in contrast to CGbeta-N13, CGbetaWT revealed no aggregation in medium. These results indicate that the backbone structure consisting of 114 amino acids and N-linked glycosylation at Asn(30) is involved in the aggregation of LHbeta. Moreover, N-glycosylation at Asn(13) does not prevent such aggregation, but instead plays an important role in correct folding for both LHbeta- and CGbeta-subunits to be secreted as monomer.

A case of thrombopoietin-producing ovarian carcinoma confirmed by immunohistochemistry

A case of ovarian carcinoma with thrombopoietin production is reported. A 49-year-old Japanese woman had serous cystadenocarcinoma of the right ovary with peritoneal spread. The platelet count was elevated to 432 x 10(9)/L. Enzyme-linked immunosorbent assay of the serum demonstrated remarkably high levels of thrombopoietin (2.96 fmol/ml). Immunohistochemical examination using an antibody specific for thrombopoietin revealed positive staining in the carcinoma cells, confirming thrombopoietin production.

Expression of asialoglycoprotein receptor in human fetal liver

Asialoglycoprotein (ASGP) receptor, which exists in hepatic parenchymal cells, plays important roles in the clearance of desialylated glycoproteins from the circulation. To study the expression of ASGP receptor in human fetal liver, specimens were obtained after therapeutic/spontaneous abortion or at autopsy with informed consent. Reverse transcription polymerase chain reaction and immunohistochemical staining showed that ASGP receptor was present as early as 15 weeks of gestation in human fetal liver. In liver at 15 weeks-gestation it was stained uniformly in cytoplasm as seen in HepG2 cells. As gestation proceed the ASGP receptor was frequently observed on the cell surface and intracellular staining showed a spotted distribution. We conclude that the expression of ASGP receptor is an early event in the developmental process of fetal liver. Furthermore, the distribution of ASGP receptor changes as the liver develops.

Comparison of complications of vaginal hysterectomy in patients with leiomyomas and in patients with adenomyosis

We reviewed 1246 vaginal hysterectomies performed at Handa City Hospital between January 1984 and December 1996. We divided the patients into 2 groups: those with leiomyomas (n = 893) and those with adenomyosis (n = 353). There was no difference in operative time and estimated blood loss between the 2 groups when analyzed by uterine weight. However, adenomyosis was associated with an increased risk of bladder injury.

Gonadotropin-releasing hormone-induced elevation of serum hCG in choriocarcinoma: a case report

We evaluated the effect of GnRH on the serum hCG level in gestational trophoblastic disease (GTD). Five patients with GTD were studied. Three patients had hydatidiform mole (two complete and one partial mole) and two had choriocarcinoma. Blood samples were collected immediately before and 30, 60 min after the 100 microg GnRH iv injection, followed by hCG assay. Only one case of choriocarcinoma demonstrated an hCG increase after intravenous administration of GnRH (positive GnRH test). In that case, the hCG level dropped to the normal range after eight cycles of chemotherapy but the GnRH test was still positive, suggesting the existence of viable cancer cells. Since the GnRH test became negative, no increase in hCG has been observed, indicating that the patient achieved complete remission. Although a positive GnRH test is not common in GTD, GnRH test before treatment might be useful to find a positive case where the test can be repeated to determine complete remission and the time when the chemotherapy may be discontinued.

Magnetic resonance imaging with gadolinium-diethylenetriamine pentaacetic acid is useful in assessment of tubal patency in a patient with iodine-induced hypothyroidism

A 32-year-old woman presented for evaluation of primary infertility. Because she had a history of iodine-induced hypothyroidism, conventional hysterosalpingography was contraindicated. Tubal patency was assessed by magnetic resonance imaging (MRI) after infusion of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA). Visualization of the contrast medium in the peritoneal cavity revealed tubal patency. Our case indicates that MRI with gadolinium-diethylenetriamine pentaacetic acid is a safe, simple, and easy way to confirm that at least one tube is patent when a patient is at risk for hysterosalpingography. To our knowledge, this is the first report that tubal patency was diagnosed on MRI.

Conservative handling of the uterus in a 10-week cervical pregnancy case

A patient with a living 10-week old cervical pregnancy who desired to preserve fertility was successfully treated with methotrexate, intraamniotic KCI injection and endocervical curettage. In the case of living cervical pregnancy even after 10 weeks, conservative treatment remains an option, although intensive management and care should be given.

Cord blood IgE against milk and egg antigens

The aim of the present study was to reevaluate the prenatal production of specific IgE for eggs and milk and, in those cases, to determine whether there is a relation to the amount of maternal egg and milk intake. Total and specific IgEs from 160 cord blood-samples were determined by immunoassays using a paramagnetic particle solid phase and an enzyme-mediated chemiluminescent reaction for signal detection. The levels of cord blood IgE for total, egg, and milk were 0.63 +/- (SD) 1.10 IU/ml, 0.020 +/- 0.055, and 0.036 +/- 0.053 IU/ml, respectively. IgE levels specific to egg and milk over 0.03 IU/ml were observed in 33 and 70 out of 160 cases, respectively. To address whether the maternal intake of eggs and milk affects the level of cord blood IgEs, all mothers except 9 were interviewed, and the amount of eggs and milk taken during pregnancy was recorded. No correlation was seen between egg and milk intakes and cord blood IgE levels. Our data demonstrate a high incidence of the prenatal production of specific IgE for eggs and milk which is independent of maternal egg and milk intakes.

Cystic teratoma of the greater omentum: a case report and review of the literature

Cystic teratoma in the greater omentum remains one of gynecology's rarest entities. A 28-year-old woman presented with a goose-egg-sized mass in the right lower quadrant. At laparotomy, the mass proved to be a cystic teratoma of the greater omentum. To our knowledge, this report documents the first case where an omental pedicle was torsioned.

Effects of gonadotropin, estrogen, and progesterone on c-mos gene expression in mouse oocytes in vivo and in vitro

OBJECTIVE

To analyze the effects of gonadotropin and ovarian steroid hormones on the gene expression of c-mos in mouse oocytes.

METHODS

The changes of c-mos messenger RNA (mRNA) levels in oocytes were examined after the administration of pregnant mare's serum gonadotropin (PMSG) in vivo, or after incubation with estrogen and/or progesterone in vitro. Five IU PMSG was injected intraperitoneally to female immature mice, and human chorionic gonadotropin was also injected intraperitoneally 48 hours after the PMSG injection, with or without mating with male mice. The oocytes were collected from follicles or oviducts at 24, 30, 36, 42, 48, 60, 72, and 84 hours after the injection. The RNAs were extracted from 5 oocytes at each time point, and a reverse-transcription polymerase chain reaction using specific primers to c-mos DNA was performed to measure the relative amount of c-mos mRNA.

RESULTS

The c-mos mRNA in oocytes at 36 hours after the injection was 2.7 times higher than that at 24 hours. The c-mos mRNA level gradually decreased thereafter, and after ovulation the level was only 1/10 of the peak level. When the oocytes that were retrieved 24 hours after PMSG injection were incubated with 800 ng/ml estradiol 17-beta or 600 ng/ml progesterone for 120 minutes, the c-mos gene expression was significantly suppressed or stimulated, respectively, in comparison with the absence of these substances.

CONCLUSION

Although the regulatory mechanism of c-mos gene expression in oocytes is still unclear because the result obtained from the in vitro study, that estrogen suppressed the c-mos gene expression directly, was inconsistent with the result of the in vivo study, that increases of both c-mos mRNA and estrogen occurred simultaneously with PMSG stimulation in the early phase of preovulatory oocytes, our present study revealed that gonadotropin and steroid hormones might affect c-mos gene expression in mouse oocytes indirectly and/or directly.

Cystine knot of the gonadotropin alpha subunit is critical for intracellular behavior but not for in vitro biological activity

The common alpha subunit of glycoprotein hormones contains five disulfide bonds. Based on the published crystal structure, the assignments are 7-31, 59-87, 10-60, 28-82, and 32-84; the last three comprise the cystine knot, a structure also seen in a variety of growth factors. Previously, we demonstrated that the efficiency of secretion and the ability to form heterodimers by alpha subunits bearing single cysteine residue mutants in the cystine knot were significantly reduced. These results suggested that the cystine knot is critical for the intracellular integrity of the subunit. To assess if the presence of the free thiol affected the secretion kinetics, we constructed paired cysteine mutants of each disulfide bond of the alpha subunit. The secretion rate for these monomers was comparable with wild type except for the alpha-10-60 mutant, which was 40% lower. The recovery of the alpha7-31 and alpha59-87 mutants was greater than 95%, whereas for the cystine knot mutants, it was 20-40%. Co-expression of the wild-type chorionic gonadotropin beta subunit with double cysteine mutants did not enhance the recovery of alpha mutants in the media. Moreover, compared with wild-type, the efficiency of heterodimer formation of the alpha10-60 or alpha32-84 mutants was less than 5%. Because subunit assembly is required for biological activity, studies on the role of these disulfide bonds in signal transduction were not possible. To bypass the assembly step, we exploited the single chain model, where the alpha and beta subunits are genetically fused. The recovery of secreted tethered gonadotropins bearing mutations in the cystine knot was increased significantly. Although dimer-specific monoclonal antibodies discriminated the conformation of single chain alpha10-60 and alpha32-84 mutants from the native heterodimer, these mutants were nevertheless biologically active. Thus, individual bonds of cystine knot are important for secretion and heterodimer formation but not for in vitro bioactivity. Moreover, the data suggest that the native heterodimer configuration is not a prerequisite for receptor binding or signal transduction.

Genomic classification of fish nodaviruses by molecular phylogenetic analysis of the coat protein gene

A molecular phylogenetic analysis of 25 isolates of fish nodaviruses, the causative agents of viral nervous necrosis of marine fish, was performed based on the nucleotide sequences (427 bases) of the coat protein gene. These fish nodaviruses were classified into four clusters: tiger puffer nervous necrosis virus, striped jack nervous necrosis virus, berfin flounder nervous necrosis virus, and red-spotted grouper nervous necrosis virus.

Alteration of N-linked oligosaccharide structures of human chorionic gonadotropin beta-subunit by disruption of disulfide bonds

The human chorionic gonadotropin beta-subunit (hCGbeta) is a glycoprotein in which 12 cysteine residues pair to form six intramolecular disulfide bonds. In order to elucidate the effect of each disulfide bond on glycosylation of the molecule, we analysed structures of asparagine-linked oligosaccharides of various recombinant hCGbeta produced in Chinese hamster ovary (CHO) cells: wild-type hCGbeta (betaWT) and mutants in which any one of the six intramolecular disulfide bonds had been disrupted by site-directed mutagenesis. SDS-PAGE analysis of betaWT and these mutants before and after digestion with endoglycosidase F and H revealed structural changes in the oligosaccharide moieties of some mutants. In addition, structural analysis of oligosaccharides obtained from metabolically labeled betaWT and a mutant showed that the mutant contained additional high mannose type oligosaccharides. These results suggest that elimination of a specific disulfide bond, resulting in a change in the protein conformation, disturbs the normal assembly of the mature complex type oligosaccharides in the hCGbeta molecule.

Apoptosis in human endometrial and endometriotic tissues

Apoptosis has recently been proposed to represent programmed cell death. Several investigations have revealed that uterine endometrium in mammals can be regulated by apoptosis. However, apoptosis may be less likely to occur in human eutopic endometrium. On the other hand, immunoreactivity of Bcl-2 that may serve a regulatory function in protecting from undergoing apoptosis was observed in uterine endometrial glandular cells in the proliferative phase through to the early secretory phase. In endometriotic tissues, although apoptosis was detected in all the samples from ovarian endometriosis, it was indicated in only a few tissues from adenomyosis. Bcl-2 was negative in almost all samples from ovarian endometriosis, whereas it was positive in all adenomyotic tissues from cases in the proliferative phase, but in none of tissues from cases in the secretory phase. Thus, ovarian endometriosis can be discriminated from adenomyosis based on the existence of apoptosis though both represent a type of ectopic endometrial tissue, and the pathogenesis or condition of the cells may be different between ovarian endometriosis and adenomyosis.