Maternal screening and postpartum vaccination for measles infection in Japan: a cohort study.

We investigated the prevalence of measles-sensitive pregnant women and the clinical usefulness of measles vaccination in postpartum women. Measles antibody levels were measured in 751 pregnant women. Forty-four women were vaccinated postpartum, and screened for antibody levels and adverse effects 1 month after vaccination. The prevalence of measles-sensitive pregnant women was 10-20%, with the highest prevalence in those under 24 years of age. Almost all (97.7%) vaccinated women acquired immunity, and did not show any adverse effects. Serum measles antibody levels should be determined in all pregnant women as a screening tool,and sensitive women should be vaccinated immediately after delivery.

The initial disparity vergence elicited with single and dual grating stimuli in monkeys: evidence for disparity energy sensing and nonlinear interactions.

We recorded the initial vertical vergence eye movements elicited in monkeys at short latency ( approximately 70 ms) when the two eyes see one-dimensional (1D) horizontal grating patterns that are identical except for a phase difference (disparity) of one-quarter wavelength. With gratings composed of single sine waves, responses were always compensatory, showing Gaussian dependence on log spatial frequency (on average: peak = 0.75 cycles/deg; SD = 0.74; r(2) = 0.980) and monotonic dependence on log contrast with a gradual saturation well described by the Naka-Rushton equation (on average: n = 0.89; C(50) = 4.1%; r(2) = 0.978). With gratings composed of two sine waves whose spatial frequencies were in the ratio 3:5 and whose disparities were of opposite sign (the 3f5f stimulus), responses were determined by the disparities and contrasts of the two sine-wave components rather than the disparity of the features, consistent with early spatial filtering of the monocular inputs before their binocular combination and mediation by detectors sensitive to disparity energy. In addition, responses to the 3f5f stimulus showed a nonlinear dependence on the relative contrasts of the two sine waves. Thus on average, when the contrast of one sine wave was 2.3 times greater than that of the other, the one with the lower contrast was largely ineffective as though suppressed, and responses were determined almost entirely by the sine wave of higher contrast: Winner-Take-All. These findings are very similar to those published previously on the vertical vergence responses of humans, indicating that the monkey provides a good animal model for studying these disparity vergence responses.

Messenger ribonucleic acid expression profile in peripheral blood cells from RA patients following treatment with an anti-TNF-alpha monoclonal antibody, infliximab.

OBJECTIVES: We monitored the mRNA expression profiles of peripheral blood cells during treatment with a TNF-alpha inhibitor, infliximab, in patients with RA. Using a DNA microarray analysis, we demonstrated a unique set of genes, with distinct baseline and post-treatment changes in expression between responders and non-responders to infliximab treatment. METHODS: Using a customized low-density cDNA microarray with 747 genes and a reliable data collection system, we monitored the mRNA expression profiles of whole blood cells from 18 RA patients before and after the infusion of infliximab for up to 22 weeks. The clinical response to treatment with infliximab was determined using the ACR response criteria, the disease activity score of 28 joints (DAS28), and individual clinical parameters. The patients were classified as responders or non-responders based on their ACR50% response at 22 weeks. RESULTS: Approximately 15% of the total genes were found to exhibit a >1.5-fold change, compared with their reference values, at one or more time points during the 22 weeks of infliximab therapy. The expression of inflammatory genes, such as IFN-related genes, was strongly correlated with the serum level of CRP and the DAS28. The increased expression of inflammatory genes in responders was normalized within 2 weeks and then remained at a normal level during the treatment period. In contrast, in the non-responders, the elevated expression at baseline, although it was significantly decreased at 2 weeks, returned to the baseline level after 14 weeks. In addition to inflammatory genes, we identified several groups of genes with distinct differences in expression between the responders and non-responders. CONCLUSIONS: Our results suggest that a customized low-density microarray is useful for monitoring mRNA expression profiles in peripheral blood cells, enabling us to identify a unique set of genes with differentially regulated expressions in responders and non-responders to a TNF inhibitor among patients with RA.

Ocular following responses of monkeys to the competing motions of two sinusoidal gratings.

Ocular following responses (OFRs) were elicited in monkeys at short latencies ( approximately 50ms) by applying motion in the form of successive 1/4-wavelength steps to each of two overlapping vertical sine-wave gratings that had different spatial frequencies. In the first experiment, the two sine waves had spatial frequencies in the ratio 3:5 and moved in opposite directions. The initial OFRs showed a highly nonlinear dependence on the relative contrasts of the competing sine waves. On average, when the contrast of one was less than a third of that of the other then the one with the lower contrast became ineffective - as though suppressed - and the OFR was entirely determined by the sine wave of higher contrast: winner-take-all. In a second experiment, the two sine waves had spatial frequencies in the ratio 3:7 and moved in the same direction (though at different speeds). The initial OFRs again showed a highly nonlinear dependence on the relative contrasts of the competing sine waves, with a winner-take-all outcome when the contrasts of the two sine waves were sufficiently different. In both experiments, the nonlinear dependence on the relative contrasts of the competing sine waves was well described by a contrast-weighted-average model with just two free parameters. These findings were very similar to those of [Sheliga, B.M., Kodaka, Y., FitzGibbon, E.J., Miles, F.A., 2006c. Human ocular following initiated by competing image motions: evidence for a winner-take-all mechanism. Vision Res. 46, 2041-2060] on the human OFR, indicating that the monkey is a good animal model for studying the nonlinear interactions that emerge when competing motions are used.

Amniotic fluid levels of tumor necrosis factor-alpha and soluble tumor necrosis factor receptor 1 before and after the onset of labor in normal pregnancies.

Tumor necrosis factor-alpha (TNF-alpha) is present in human placental and uterine cells and promotes the regulation of trophoblast growth and invasion. Tumor necrosis factor receptor 1 (TNF-R1) is a receptor for TNF-alpha, and soluble TNF-R1 (sTNF-R1) is present in amniotic fluid after receptor shedding. We evaluated whether amniotic fluid TNF-alpha and sTNF-R1 levels during labor differed from those before the onset of labor in normal pregnancies. This study enrolled 34 Japanese women experiencing normal pregnancies with single fetuses who had no infection. Of these subjects, 17 went into labor and had subsequent term deliveries (the labor group), and the other 17 underwent cesarean section without labor (the nonlabor group). The average gestational age at entry was 38-39 weeks of gestation. Maternal ages and gestational ages did not differ significantly between the two groups. Amniotic fluid was collected and the TNF-alpha and sTNF-R1 levels were determined by the ELISA method. Each of these levels was compared between the two groups. There was a significant increase in amniotic fluid TNF-alpha levels in the labor group. However, amniotic fluid sTNF-R1 levels did not differ significantly between the two groups. Amniotic fluid TNF-alpha may promote the onset of labor at term and/or term labor contributing to subsequent delivery may induce the production and secretion of TNF-alpha into the amniotic cavity. There was no pregnancy-associated increase in receptor shedding or cell apoptosis at the onset of labor.

Thrombin-antithrombin complex and alpha-plasmin inhibitor-plasmin complex levels in singleton and twin pregnancies.

Thrombin-antithrombin complex (TAT) is a sensitive marker for thrombin formation, and alpha2-plasmin inhibitor-plasmin complex (PIC) is a marker for fibrinolysis. Previous studies have shown that blood coagulation and fibrinolysis are activated in normal pregnancies. Thus, the present study examined changes in TAT and PIC levels during the course of singleton and twin pregnancies and compared these markers between the two pregnant groups. The subjects were 148 pregnant women, of whom 84 were women carrying single fetuses and 64 were women with twin fetuses. Their average gestational age at entry was 10, 20, 30 and 38 weeks of gestation in singleton pregnancies and 10, 20, 30 and 35 weeks in twin pregnancies. Peripheral blood was collected, and plasma was separated after centrifugation and then stored at -20 degrees C. The TAT levels increased significantly with the progression of pregnancy in both pregnant groups, whereas the PIC levels increased significantly only in singleton pregnancies between 30 and 38 weeks of gestation. The TAT levels were significantly higher in twin pregnancies than in singleton pregnancies. The PIC levels were significantly lower in twin pregnancies than in singleton pregnancies at 35-38 weeks. Thrombin formation might be enhanced with the progression of pregnancy in both pregnant groups. This enhancement might be more intensified in twin pregnancies. Fibrinolysis might increase only in singleton pregnancies from 30 to 38 weeks of gestation. Fibrinolysis might be less intensified in twin pregnancies than in singleton pregnancies only at 35-38 weeks.

Serum levels of macrophage colony-stimulating factor in singleton and twin pregnancy.

Macrophage colony-stimulating factor (M-CSF) is present in the placenta and has been implicated in placental growth and development. M-CSF levels in peripheral blood increase significantly with progression of pregnancy in uncomplicated singleton pregnancy. This study investigated whether serum M-CSF levels in singleton pregnancy differed from those in twin pregnancy. A hundred and four pregnant women, of whom fifty-nine were women carrying single fetuses and forty-five were women with twin fetuses, participated in the study. Their average gestational age at entry was 10, 20, 30, and 38 weeks of gestation in singleton pregnancy and 10, 20, 30, and 35 weeks in twin pregnancy. Peripheral blood was collected and serum was separated after centrifugation and stored at - 20 degrees C. M-CSF levels were determined by ELISA. In both groups, the serum levels of M-CSF increased significantly as pregnancy progressed. M-CSF levels were relatively higher in twin pregnancy than in singleton pregnancy at 10, 20, and 30 weeks. At 35 and 38 weeks, the M-CSF levels were significantly higher in twin pregnancy than in singleton pregnancy. Elevation of serum M-CSF supports M-CSF production in the placenta. This elevation in twin pregnancy may be related to increased demand of M-CSF in twin pregnancy.

Profiling of proteins associated with cisplatin resistance in ovarian cancer cells.

Resistance to cisplatin is a major impediment to the successful treatment of ovarian cancer, but the precise nature of the resistance is still unclear. In the current study, we aimed to investigate and compare the protein expression profiles in cisplatin-sensitive and cisplatin-resistant ovarian cancer cell lines. We employed the recent development of surface-enhanced laser desorption/ionization ProteinChip technology to measure protein expression in three human ovarian cancer cell lines (KF-1, MN-1, and A2780) and their sublines (KF-r, MN-r, and A2780cp) resistant to cisplatin. The ProteinChip Arrays were analyzed using the ProteinChip Reader. We did not find any regularity in protein expressions in secretions of cisplatin-sensitive and cisplatin-resistant cells. But on the IMAC3 array, we captured 12 identical expressions which represent a subset of proteins whose expression levels are different between parent ovarian cancer cells and their cisplatin-resistant cells. In particular, at the molecular weight of 7829 d, three kinds of parent cell lines exhibited an elevated expression and their cisplatin-resistant sublines revealed a lowered expression. At the molecular weight of 6881 d, for KF and MN cell lines, opposite protein expressions were seen in the parent cell line and its cisplatin-resistant subline. We think the interesting protein expressions perhaps suggest some mechanisms involved in cisplatin resistance.

Interleukin-6 concentrations in the placenta and blood in normal pregnancies and preeclampsia.

AIM: To evaluate whether IL-6 concentrations in the placenta and blood from women with preeclampsia differed from those in normal pregnancies. METHODS: This study involved 41 pregnant women carrying single fetuses. Of these pregnancies, 23 were normal pregnant and 18 were preeclamptic patients. The average gestational age at entry was 37-38 weeks of gestation. Blood was collected before the onset of labor. Serum was separated and stored at -20 degrees C. A tissue segment of the placenta was cut and chilled in liquid nitrogen immediately after delivery and stored at -80 degrees C. The frozen tissue was added to phosphate-buffered saline and fully homogenized. After centrifugation, the separated supernatant was stored at -80 degrees C. IL-6 levels in separated serum and IL-6 and total protein (TP) levels in separated supernatant were measured. The presence of IL-6 in the placenta was evaluated by immunohistochemistry in five preeclamptic and five normal pregnant patients. RESULTS: Neither IL-6/TP levels in the placenta nor IL-6 levels in blood differed significantly between the two groups. IL-6 immunostaining on trophoblastic cells in the placenta was weak in one and absent in four in normal pregnancies, and absent in all patients with preeclampsia. There was no strong immunostaining for IL-6 in preeclampsia by immunohistochemistry. CONCLUSIONS: Our findings suggest that IL-6 in the placenta and blood does not play a significant role in the induction of an immunologic imbalance, which may contribute to the etiological mechanism leading to preeclampsia.

Centripetal bias on preparation for smooth pursuit eye movements based on the anticipation.

It has been reported that a brief perturbation of a stationary target during fixation induces larger eye movement when monkeys anticipate future smooth pursuit than when they do not. Here, we recorded eye movements in human subjects after briefly perturbing a target and the eccentricity of its initial position was changed under three conditions: (1) subjects anticipated saccades for a target that appeared before; (2) they anticipated smooth pursuit for a target that appeared before; and (3) they anticipated smooth pursuit but did not know beforehand where the target started from. We found that in condition 2 substantial eye movements were induced by the perturbation started moving toward the center. However, weak responses were observed in conditions 1 and 3. These results indicate that ocular responses to brief perturbations of the target at eccentric positions are increased with centripetal bias when human subjects prepare for future smooth pursuit.

Increased levels of serum macrophage colony-stimulating factor before the onset of preeclampsia.

Macrophage colony-stimulating factor (M-CSF) is known to play a central role in maintaining pregnancy. The present study determined whether the increase in serum M-CSF levels preceded the onset of preeclampsia. Blood was collected from 110 normotensive pregnant women at risk for preeclampsia who were carrying single fetuses at about 30 weeks of gestation. After centrifugation, serum was stored at -20 degrees C until assay. Eighteen women developed preeclampsia at a later stage of pregnancy (group 1), while 88 women continued to have normotensive pregnancies until delivery. Thirty-four of the 88 women with normotensive pregnancy who were matched for age and parity were selected to form a control group (group 2). Serum M-CSF levels were determined by the sandwich ELISA method using three antibodies. Serum level of M-CSF was 1,266 U/ml (median) in group 1 and 1,082 U/ml in group 2. Serum M-CSF levels were significantly higher in group 1 than in group 2 (p < 0.0002). Increased levels of serum M-CSF markedly precede the development of clinical manifestations of preeclampsia. High serum M-CSF levels support M-CSF elevation in the placenta. This elevation at 30 weeks of gestation may be associated with placental hypoxia, which is considered the cause of preeclampsia.

Suppressive effects of F-1322 on the antigen-induced late asthmatic response and pulmonary eosinophilia in guinea pigs.

We investigated the effects of F-1322 (N-[2-[4-(benzhydryloxy)piperidino]ethyl]-3-hydroxy-5-(3-pyridylmethoxy)-2-naphthamide), a new compound that inhibits both thromboxane A2 synthetase and 5-lipoxygenase and that functions as a histamine antagonist, on the Ascaris antigen-induced late asthmatic response and pulmonary eosinophilia in guinea pigs. Oral administration of F-1322 (10-100 mg/kg) inhibited the antigen-induced late asthmatic response in a dose-dependent manner. Histological analysis revealed that F-1322 prevented the accumulation of eosinophils in the airways and this was paralleled by a decrease in the number of eosinophils and lymphocytes recovered in bronchoalveolar lavage fluid. F-1322 (0.1-10 microM) inhibited eotaxin-induced chemotaxis and actin polymerization of eosinophils in vitro in a concentration-dependent manner, while oral administration of F-1322 dose-dependently suppressed the migration of eosinophils into the airways in vivo in response to infusion of interleukin 5 and eotaxin in combination. F-1322 may, thus, improve the late asthmatic response in this model, in part, by preventing the accumulation of eosinophils in the airways. The pharmacological profile of F-1322 indicates that this drug is likely to be useful in the treatment of allergic diseases such as asthma.

[Pressure wire guide provisional coronary stent implantation].

OBJECTIVES: Whether coronary artery lesion successfully dilated by balloon angioplasty should be stented or not is unclear. The purpose of this study is to evaluate the provisional stent implantation method assessing residual ischemia by pressure wire. METHODS: Thirty-one patients with de-novo lesions suitable for stenting were enrolled in a pressure wire guided provisional stent study. The pressure wire was used to assess the fractional flow reserve(FFR) before and after balloon angioplasty. When the FFR after angioplasty was less than 0.75, stent implantation was planned. Patients with lesions consisting of an intermediate stenosis proximal to the target lesion, chronic total occlusion, bypass graft and left main lesion were excluded from the study. Stent implantation was permitted even if the FFR was more than 0.75 when the operator thought stenting was necessary. Medical treatment was given with aspirin 162 mg/day, cilostazol 200 mg/day for 6 months and additional ticlopidine 200 mg/day for a month after stenting the lesion. RESULTS: Target vessel was the left anterior descending coronary artery in 19 lesions, the right coronary artery in 3, and the circumflex coronary artery in 9. Stent implantation was performed in seven (23%) of 31 lesions and the other 24(77%) lesions were treated with only balloon angioplasty. The FFR before intervention was 0.58 +/- 0.16, and improved to 0.87 +/- 0.07 (p < 0.0001). Percentage diameter stenosis before intervention was 70.7 +/- 12.6% and improved to 20.1 +/- 13.3% (p < 0.0001) after intervention. There was no major cardiac event (death, coronary artery bypass grafting, myocardial infarction, stent thrombosis). Six months follow-up angiography was performed in 27 patients (87%). Angiographic restenosis (percentage diameter stenosis > or = 50%) was found in four patients (15%). A new lesion was found in two patients. Target vessel revascularization was performed in six patients (21%). CONCLUSIONS: Lesions successfully dilated by balloon angioplasty with FFR > or = 0.75 do not require stenting.

Increased excretion of N-acetyl-beta-D-glucosaminidase and beta2-microglobulin in gestational week 30.

BACKGROUND: Little is known about when the urinary excretion of a combination of N-acetyl-beta-D-glucosaminidase (NAG) and beta2-microglobulin (beta2MG) concentration [relative to creatinine (Cr)] reaches maximal values during uncomplicated normotensive pregnancy. This study was thus designed to analyze when urinary excretion of biochemical parameters was increased during normotensive pregnancy. METHODS: NAG, beta2MG, total protein, albumin, and Cr were simultaneously measured in random (untimed) midstream urine samples from 22 healthy nonpregnant women and from 82 normotensive pregnant women (22 in gestational week 20, 25 in week 30, and 35 in week 37). RESULTS: NAG/Cr and beta2MG/Cr ratios were significantly higher (P < 0.01-0.05) in the normotensive pregnant women in gestational week 30 than in the nonpregnant control subjects and normotensive pregnant women in gestational week 20. The NAG/Cr and beta2MG/Cr ratios showed maximal values in gestational week 30. The total protein/Cr ratio was significantly higher in gestational weeks 20, 30, and 37 than in the control subjects. The albumin/Cr ratio was significantly higher in women in gestational week 30 and 37 than in women in gestational week 20 and in the control subjects. CONCLUSIONS: The excretion of both NAG and beta2MG relative to Cr was increased and showed the maximal values in gestational week 30 during normotensive pregnancy. The increase in a tubular enzyme (NAG) might be caused by renal tubular damage, and that in a low molecular weight protein (beta2MG) might result from decreased renal tubular reabsorption. These findings suggest that renal tubular damage and reabsorption dysfunction were increased in gestational week 30.

The fertility and pregnancy outcomes of the patients who underwent preservative operation followed by adjuvant chemotherapy for malignant ovarian tumors.

The fertility and pregnancy outcomes of the patients were studied, who previously underwent preservative operation for malignant tumors, including those of borderline malignancy, in our ward from 1981 to 1995. For each of the 9 patients, unilateral ovary was preserved, the range of their ages before operation was 10 to 28 years old, and histologically, 7 patients had tumors derived from germ cells, and 2 had those from epithelial cells. As for clinical stages according to the FIGO's criteria, 5, 1, 2 and 1 patients were in stage I, II, III and IV, respectively. The regimens of the combination chemotherapy for patients with germ cell tumors were PVB (cisplatin, vinblastine and bleomycin), PEP (cisplatin, etopside and pepleomycin), PVP (cisplatin, vinblastine and pepleomycin), AVAC (doxorubicin, vincristine, actinomycin-d and cyclophosphamide). Those for the patient with epithelial tumors were CAP (cyclophosphamide, doxorubicin and cisplatin), CP (cyclophosphamide and cisplatin). Eight patients have been doing well, although 1 of them experienced recurrence and died. Amenorrheic periods of 2 to 12 months were noticed in 3 patients, although in all of them, ovulatory cycles recovered. Eight pregnancies were reported: 5 term delivery with normal babies, and others were preterm termination due to abruptio placenta with a baby of appropriate for date, spontaneous abortion, and artificial termination. We suppose that the combination chemotherapy applied for the patients in the present study affected neither the fertility of the patients nor the outcomes of the pregnancies.

Changes in plasma soluble CD26 and CD30 during pregnancy: markers of Th1/Th2 balance?

The theory that the Th1 and Th2 cell ratio shifts towards Th2 dominance during pregnancy may improve fetal survival has gained support from recent studies. Also, the variation in the Th1/Th2 cell ratio is reportedly associated with intrauterine growth retardation and preeclampsia. On the basis of these findings, the analysis of the Th1/Th2 balance may be useful in predicting severe complications during pregnancy. However, simple methods for the analysis of Th1/Th2 balance are presently not available. Recently, it has been reported that regulation of CD26 cell surface expression correlates with the production of Th1-like cytokines. On the other hand, previous studies proposed that the sCD30 molecule is an activation marker useful for evaluation of a Th2 immune response. It is, therefore, possible that the analysis of the Th1/Th2 balance during pregnancy by measuring plasma sCD26 and sCD30 simultaneously is a simple and useful method. We herein demonstrate that combined analysis of sCD26 and sCD30 is a potent surrogate tool to evaluate the Th1/Th2 balance during pregnancy.

Antiulcer effect of lafutidine on indomethacin-induced gastric antral ulcers in refed rats.

Lafutidine is a new type antiulcer agent with antisecretory and gastroprotective activities. We investigated the effect of lafutidine on indomethacin-induced antral ulcer in refed rats. Subcutaneous indomethacin injection resulted in the formation of gastric antral ulcer. Lafutidine (1-10 mg/kg, p.o.) reduced the area of ulcer in a dose-dependent manner when administered immediately after the indomethacin injection. Capsaicin at 3 mg/kg, p.o. and 16,16-dimethyl prostaglandin E2 at 3 microg/kg, p.o. also reduced the ulcer area. Chemical deafferentation of capsaicin-sensitive neurons or N(G)-nitro-L-arginine treatment aggravated the ulcer formation and abolished the preventive effect of lafutidine and capsaicin. After the induction of gastric ulcer, lafutidine given twice daily for 2.5 days reduced the area of ulcer in a dose-dependent manner with a significant effect at 10 mg/kg, p.o., as compared with that of the control group. In chemically-deafferentated rats, lafutidine did not show any healing effect. Cimetidine (30 mg/kg, p.o.) and famotidine (1 mg/kg, p.o.) had no significant effect on indomethacin-induced antral ulcer. These results may suggest that lafutidine, unlike cimetidine and famotidine, can prevent the indomethacin-induced antral ulcer formation and accelerate the healing of the ulcer in refed rats through mechanisms involving the capsaicin-sensitive afferent neurons and nitric oxide.

Gastroprotective mechanism of lafutidine, a novel anti-ulcer drug with histamine H2-receptor antagonistic activity.

Lafutidine (CAS 118288-08-7, FRG-8813) is a novel histamine H2-receptor antagonist with gastroprotective activity. The aim of this study was to investigate the property of the gastro-protective activity of lafutidine by examining the effect on ammonia-induced change in transmucosal potential difference (PD), basal gastric mucosal blood flow (GMBF) and noxious agent-induced cell damage. Intragastrical application of lafutidine accelerated the recovery of the PD reduction after exposure of the mucosa to 0.25% ammonia solution and the accelerating effect was abolished by chemical deafferentation, but not with indometacin, a cyclooxygenase inhibitor. The application of capsaicin, as a reference compound, significantly promoted the recovery of the ammonia-induced PD reduction and this effect was not altered with indometacin. Lafutidine given intragastrically caused a sustained increase in GMBF in a dose-dependent fashion, which was also completely inhibited in the deafferentated rats. In vitro studies revealed that, in contrast to 16,16-dimethyl prostaglandin E2, lafutidine did not protect isolated gastric superficial epithelial cells from ethanol- or ammonia-induced damage. In conclusion, the gastroprotection of lafutidine is induced by promoting the restitution of the damaged mucosa after a noxious agent, not by directly protecting the epithelial cells and this effect may be caused through the mechanism of capsaicin-sensitive afferent nerves.

[TTV materno-infantile infection--a study on the TTV frequency in Japanese pregnant women and the natural history of TTV mother-to-infant infection].

We preliminarily describe the frequency of TTV in Japanese pregnant women, non-parenteral, postnatal materno-infantile transmission of TTV, and 2 cases in which infantile development of the TTV carrier-state seemed to have occurred by vertical infection. The sera of 85 hepatitis B, C and G-positive and 36 non-pathological pregnant Japanese women were screened for the presence of TTV DNA with a use of semi-nested PCR. The positive rates were 25.9 and 27.8%, respectively. No significant differences were gained between these two groups. Twenty-one infants were born to the TTV carrier women. Of them, 9 infants (42.9%) sero-converted to TTV DNA-positive after their age of 4 months. Among the infants who were breast-fed, the positive sero-conversion rate of TTV DNA tended to increase as the length of the breast feeding period increased. Serum AST/ALT levels stayed within normal upper limits in the 9 infants. This study indicates the frequent, and furthermore, certain possibility of non-parenteral (i.e., via breast milk), postnatal vertical infection of TTV.