An ELISA-based assay for detergent-solubilized cellular beta 1,4-galactosyltransferase activity. Use of a polyacrylamide derivative with GlcNAc-beta side chains as a solid phase acceptor substrate

In our previous paper [Oubihi et al. (1998) Anal. Biochem., 257, 169-175], we have shown that a polyacrylamide-derived synthetic glycopolymer with GlcNAcbeta side chains, termed PAP(GlcNAcbeta), is useful as a solid phase acceptor substrate for the ELISA-based analyses of soluble beta1,4(-)galactosyltransferase (GalT) activity in milk. This method is now used to assay detergent-solubilized cellular GalT. The glycopolymer coated on polystyrene plates was shown to be highly stable against the non-ionic and ionic detergents tested (0 approximately 5% solutions of Triton X-100 and SDS). Such stability made it possible to incubate the ELISA plate with detergent-solubilized GalT and to wash the ELISA plate with SDS solution after the GalT reaction, leading to high accuracy and sensitivity of this assay. The GalT activity was assayed using this method for 1% Triton X-100 extracts of various tissue samples of mice and several cultured cell lines. The results showed that the specific GalT activity of tissue extracts was low in brain and intestine, and high in ovary, muscle, and kidney. As for the cultured cell lines, COS7, COMMA-1D and C2C12 cells showed high specific activity, while CHO and MDCK cells showed low activity. The myoblast C2C12 had a slight increase in GalT activity during starvation-induced cell differentiation. On the other hand, GaIT-I transcript estimated by RT-PCR rather decreased during C2C12 cell differentiation, suggesting a differentiation-dependent switch in GalT isozymes. Taken all together, the ELISA-based assay using PAP(GlcNAcbeta) as a solid phase acceptor substrate was demonstrated to be a useful method for the assay of membrane-bound galactosyltransferases.

Vitrectomy for macular hemorrhage associated with retinal arterial macroaneurysm

OBJECTIVE

To evaluate the safety and efficacy of pars plana vitrectomy to treat massive macular hemorrhage caused by retinal arterial macroaneurysm.

DESIGN

Retrospective case series.

PARTICIPANTS

Eight eyes of eight patients.

METHODS

We retrospectively reviewed the charts for eight eyes of eight patients in which pars plana vitrectomy had been performed to remove a massive macular hemorrhage secondary to a ruptured retinal arterial macroaneurysm. In each case, the preretinal/intralamellar hemorrhage was removed, and in three of the eight eyes a subretinal hemorrhage was removed via a retinotomy after clot lysis using tissue plasminogen activator.

MAIN OUTCOME MEASURE

Pars plana vitrectomy to treat macular hemorrhage secondary to retinal arterial macroaneurysm.

RESULTS

The duration of symptoms ranged from 10 to 80 days (average, 31 days). The preoperative visual acuities ranged from counting fingers to 0.09. Follow-up ranged from 3 to 36 months (average, 19 months). The postoperative visual acuities improved in seven eyes and remained unchanged in one; vision was better than 0.1 in six eyes and better than 0.4 in five. Postoperative complications included a mild vitreous hemorrhage in two eyes, a macular hole in one, and a cataract in two.

CONCLUSIONS

Pars plana vitrectomy appears to be relatively safe and effective in treating massive macular hemorrhage caused by a retinal arterial macroaneurysm.

Production and accumulation of thrombospondin-1 in human retinal pigment epithelial cells

PURPOSE

To investigate the production and release of thrombospondin-1 (TSP-1), a natural inhibitor of angiogenesis, by human retinal pigment epithelial (RPE) cells to clarify the possible role of TSP-1 in maintaining intraocular angiogenesis.

METHODS

Human RPE cells were isolated from a human cadaveric eye and cultured in medium with 5% newborn calf serum. TSP-1 messages in the purified RNA of RPE cells were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Intracellular TSP-1 peptides were detected by cytofluorographic analysis. TSP-1 peptides in the culture medium on RPE cells were measured by sandwich enzyme-linked immunosorbent assay (ELISA). TSP-1 specific immunofluorescent staining was tested in RPE cells cultured on glass slides and in a human retinal tissue specimen.

RESULTS

mRNA specific for TSP-1 was found in RT-PCR products from RPE cells, and it showed a time-dependent increase from the beginning of the culture. Intracellular staining for TSP-1 was identified by flow cytometry. The sandwich ELISA identified a time-dependent increase of TSP-1 peptides in the culture medium of RPE cells. Immunostaining for TSP-1 was observed in the cytoplasm of RPE cells cultured on glass slides. Positive immunostaining of TSP-1 was observed in the cytoplasm of the RPE layer in the human retinal tissue specimen.

CONCLUSIONS

RPE cells can produce and release TSP-1 in vitro, and TSP-1 accumulates in the cytoplasm of RPE cells in vivo as well as in vitro. The production of TSP-1 by RPE cells is influenced by the state of proliferation and/or cell density. TSP-1 appears to be an important control factor in retinal and choroidal neovascularization.

[New classification of the T category for pancreatic cancer]

The General Rules for the Study of Pancreatic Cancer (4th edition) is widely used in Japan, but several problems have been detected. One is the complexity of classification of the T category of peripancreatic invasion. This study was undertaken to simplify the classification of the T category. In 145 patients who underwent resection of pancreatic cancer, we analyzed the prognosis of those with invasion and without invasion based on seven factors of peripancreatic invasion. Furthermore, we selected three factors (S, invasion to the anterior pancreatic capsule; RP, invasion to the retroperitoneal tissue; and PL, invasion to the extrapancreatic nerve plexus) as prognostic factors by means of stepwise multivariate linear regression analysis. Subsequently we established a new classification of the T category: T1, without invasion in all three factors; T2, with invasion in only one of the three factors; and T3, with invasion in two or three factors. The prognoses of the same patients were analyzed retrospectively, and 1-, 3-, and 5-year survival rates were 100%, 88%, and 44% in T1, 76%, 30%, and 18% in T2, and 27%, 4%, 3% in T3 patients, respectively. In conclusion, we suggest that our new classification of the T category is simple and useful for the assessment of the prognosis in pancreatic cancer.

Clinical results of fetal obstructive uropathy treated by vesicoamniotic shunting

OBJECTIVES

To report the clinical results of 5 fetuses after a vesicoamniotic shunting procedure (VASP).

METHODS

Between 1995 and 1998, 5 patients (two with prune belly syndrome, one with a cloacal anomaly, one with urethral stenosis, and one with a sacrococcygeal teratoma) underwent VASP using a double-basket catheter. We used the following selection criteria: a fetus without chromosomal defects, with oligohydramnios, and with a predicted good renal function from sequential or single fetal urinalysis (sodium concentration, chloride concentration, and osmolarity at less than 100 mEq/L, less than 90 mEq/L, and less than 210 mOsm, respectively).

RESULTS

The mean gestational age was 20.8 +/- 6.9 weeks at diagnosis, 24.2 +/- 6.0 weeks at VASP, and 30.6 +/- 6.2 weeks at delivery. In our study, 2 of 5 patients survived. One of the patients with prune belly syndrome was 18 months old at last follow-up, with hydrocephalus and a creatinine level of 0.2 mg/dL. The patient with the cloacal anomaly was 4 years old at last follow-up and had signs of clonic convulsion. However, psychomotor development was delayed in both. Of the 3 patients who died, 2 died after birth, and the autopsy determined death was due to pulmonary insufficiency. The patient with urethral stenosis died in utero.

CONCLUSIONS

Although the principal purpose of VASP is to prevent pulmonary hypoplasia and dysfunctional kidneys, VASP was not always effective, as the outcomes were poor in most of our patients. A greater standardization of patient selection and a large cohort study in the future should be considered to assess VASP.

A comparative study of Celsior and University of Wisconsin solutions based on 12-hr preservation followed by transplantation in canine models

BACKGROUND

Celsior is a recently developed extracellular-type preservation solution that is effective in organ preservation. This experimental study was designed to compare the effects of Celsior and University of Wisconsin (UW) solutions in myocardial protection, using 12-hour preservation followed by orthotopic transplantation.

METHODS

Fourteen pairs of adult mongrel dogs were divided into 2 groups. In the UW group (n = 7), UW solution at 4 degrees C was used for coronary vascular washout and storage following cardiac arrest with glucose-insulin-potassium (GIK) solution. In the Celsior group (n = 7), Celsior solution was used to produce cardiac arrest, for coronary vascular washout, and for storage. After 12-hour cold preservation, orthotopic transplantation was performed under cardiopulmonary bypass (CPB). The rate of recovery (%) of cardiac function of donor hearts was compared 1 and 2 hours after weaning from CPB, and then the transplanted hearts were harvested for histological study.

RESULTS

Hemodynamic parameters including cardiac output, left ventricular pressure (LVP), and the maximum rates of positive and negative increase of LVP after transplantation were significantly (p < 0.05) higher in the Celsior group than in the UW group 2 hours after weaning from CPB. The transmission electron microscopic study found that degeneration of the mitochondria in the Celsior group was less extensive than in the UW group.

CONCLUSION

Celsior solution enhanced the cardiac function of hearts preserved for 12 hours prior to transplantation compared to UW solution. Our results indicate that Celsior solution is equivalent or superior to UW solution for cardiac preservation.

Primary cardiac angiosarcoma associated with cardiac tamponade: case report

A 57-year-old male with primary cardiac angiosarcoma was initially admitted for cardiac tamponade. Pericardiocentesis was performed twice preoperatively, but the bloody pericardial fluid was cytologically negative for malignant cells. The tumor in the right atrium was resected during cardiopulmonary bypass. The resected tumor was 5.5x4.5x3.0cm in size and the diagnosis of cardiac angiosarcoma was made histologically. There were no tumor cells in the surgical margin. Unfortunately the patient died 3.5 months after surgery due to multiple recurrence in the pericardium. A suitable therapy for cardiac angiosarcoma is still controversial, but early antemortem diagnosis and more aggressive combined treatment should be considered.

A case report of caudal regression syndrome associated with an intraspinal arachnoid cyst

We report here a rare case of caudal regression syndrome associated with an intraspinal arachnoid cyst. The patient was a 6-month-old baby girl with multicomplex congenital abnormalities: sacrococcygeal dysgenesis and ventral curvature, large terminal cyst (myelocystocele), spinal arachnoid cyst, cerebellar hypertrophy (suspected), high imperforate anus, partial dysgenesis of the large intestine, omphalocele, atresia of the vagina, bilateral incomplete ureter duplication, incomplete pseudoduplicated bladder and bilateral talipes equinovarus. We performed plastic repair of the myelocystocele and perineal lesion for caudal regression syndrome and partial removal of the cyst wall for the intraspinal arachnoid cyst. She has been well for 3 years postoperatively, and her mental development is normal.

Peritoneal washings cytology combined with immunocytochemical staining in pancreatic cancer

BACKGROUND/AIMS

Peritoneal washings from patients with pancreatic cancer demonstrate malignant cells in 0-58% of patients. But the significance of their potential for implantation and growth after radical surgery has not been clarified.

METHODOLOGY

Peritoneal washings were collected from 74 consecutive pancreatic cancer patients during a 5-year period and studied by conventional staining and immunocytochemical staining using anti-CEA and anti-CA 19-9. Fifty of the 74 patients were resectable and the others were nonresectable.

RESULTS

Seven out of 8 patients with macroscopic peritoneal metastasis were positive in conventional staining, but all 8 patients were positive in immunocytochemical staining. Five of the 66 (8%) patients without macroscopic peritoneal metastasis were positive in conventional staining, but the positive rate increased to 14 of 66 (22%) in immunocytochemical staining. There was no statistically significant difference in post-operative cumulative survival rate between the 13 positive cytology patients and 37 negative cytology patients without macroscopic peritoneal metastasis.

CONCLUSIONS

The positive rate of peritoneal washings cytology was increased in this study by the use of immunocytochemical staining in addition to conventional staining. No statistically significant difference in post-operative cumulative survival rate between positive cytology patients and negative cytology patients without macroscopic peritoneal metastasis was observed.

Activation of phenacetin O-deethylase activity by alpha-naphthoflavone in human liver microsomes

1. The roles of different human cytochrome P450s (CYP) in phenacetin O-deethylation were investigated using human liver microsomes and recombinant proteins. Phenacetin O-deethylase (POD) activities in human liver microsomes at substrate concentrations of 10 and 500 microM were inhibited by 0.1 and 1 microM alpha-naphthoflavone and activated by 10 and 100 microM alpha-naphthoflavone. The activation of POD activity in human liver microsomes by alphanaphthoflavone was inhibited by 100 microM aniline, anti-CYP2E1 antibody, 1 microM ketoconazole and anti-CYP3A4 antibody. 2. In recombinant CYP from human B-lymphoblast cells, POD activities at a phenacetin concentration of 500 microM were detected for CYP2E1 and CYP3A4, as well as CYP1A2, CYP1A1, CYP2C19, CYP2C9 and CYP2A6. In recombinant CYP from human B-lymphoblast cells or baculovirus-infected insect cells and in reconstituted systems, a requirement of cytochrome b5 (b5) for POD activities catalysed by CYP2E1 and CYP3A4 was observed. The activation of POD activity by alpha-naphthoflavone was observed for CYP3A4, but not for CYP2E1. Co-expression of b5 with CYP3A4 enhanced the activation of POD activity by alpha-naphthoflavone. 3. In the absence of alpha-naphthoflavone, the POD activity in pooled human liver microsomes at 500 microM phenacetin was significantly inhibited (p<0.0001) by 10 microM fluvoxamine, but not by 1 microM ketoconazole. In the presence of alpha-naphthoflavone, the activity was significantly inhibited (p<0.0001) by 1 microM ketoconazole, but not by 10 microM fluvoxamine. 4. Inter-individual differences in the effects of alpha-naphthoflavone on POD activity in human liver microsomes were observed, and the involvement of CYP3A4 as well as CYP1A2 in POD activity in human liver was identified even at a low substrate concentration.

Long-term heart preservation using a new portable hypothermic perfusion apparatus

OBJECTIVE

Perfusion storage is not often used clinically compared with simple immersion because of complicated circuits and demanding management. We developed a new apparatus for preservation combined with simple immersion and continuous coronary perfusion.

METHODS

The main characteristics of this apparatus are as follows: (1) hypothermic storage, (2) does not require any energy source, (3) variable perfusion pressure, and (4) portability. The perfusion apparatus is composed of a storage chamber, a cooling chamber, and metal bars from which a perfusate bag is suspended. Adult mongrel dogs were divided into two groups: the coronary perfusion group (CP, n = 6) and the simple immersion group (SI, n = 6). Coronary vascular beds of the dog were washed out with a University of Wisconsin (UW) solution following cardiac arrest obtained using a GIK solution. The hearts were then excised. In the CP group, the heart graft, which was immersed in a 4 degrees C UW solution, was perfused with the same solution at a flow rate of 35 approximately 50 ml/hr. In the SI group, the heart graft was immersed in a 4 degrees C UW solution only. The heart graft was preserved for 12 hours in both groups. Beta-adenosine triphosphate (beta-ATP), phosphocreatine (Pcr), and inorganic phosphate (Pi) levels were measured immediately after excision of the heart, and at 3, 6, and 12 hours after preservation. Beta-ATP, Pcr, and Pi values were expressed as a percentage of control values, which had been obtained immediately after excision of the heart. Water content of the myocardium was measured prior to and after 12-hour preservation. The preserved graft was then evaluated through orthotopic transplantation.

RESULTS

Beta-ATP/Pi levels at 6 and 12 hours after preservation were significantly higher in the CP group than in the SI group (62 +/- 5 versus 39 +/- 7%, 48 +/- 5 versus 22 +/- 8%, respectively, p < 0.05). Pcr/Pi levels at 6 and 12 hours after preservation were 30 +/- 9% and 22 +/- 8%, respectively in the CP group, while Pcr/Pi levels in the SI group were detected in only one case. There was no significant difference in water content either prior to or after 12-hour preservation between the two groups. Histopathologically, irregular expansion and/or contraction of myocardial fibers were more severe in the SI group than in the CP group. The recovery rate of hemodynamic parameters 2 hours after heart transplantation was significantly (p < 0.05) higher in the CP group than in the SI group.

CONCLUSION

Stable and safe long-term canine heart preservation with continuous coronary perfusion associated with immersion is possible using this new apparatus, and may have broad clinical application.

Relationship between Fas-ligand expression on carcinoma cell and cytotoxic T-lymphocyte response in lymphoepithelioma-like cancer of the stomach

The Fas/Fas-ligand (Fas-L) system is involved in the induction of apoptosis and mediates T-cell cytotoxicity. We investigated the Fas/Fas-L system and cytotoxic T lymphocytes (CTLs) in 30 lymphoepithelioma-like cancer of the stomach (LECS) in order to understand the immune evasion of the tumor cells. Epstein-Barr virus (EBV) was detected in 15 cases in 30 LECSs. The expressions of Fas and Fas-L in tumor cells, and TIA-1, CD4, CD8 and CD56 in lymphocytes were examined by immunohistochemical staining. Apoptosis of tumor cells and lymphocytes was detected by the terminal deoxynucleotidyl-mediated dUTP-nick end labeling method (TUNEL). Expression of Fas and Fas-L was detected in tumor cells in 10 and 17 LECS, respectively. CTL consisted predominantly of CD8 (CD8(+) > CD4(+)), whereas natural killer (NK) cells were detected in 4 cases only. In Fas-L-positive tumors, the TIA-1-positive lymphocyte count was significantly lower (p < 0.05) and the number of apoptotic lymphocytes was significantly higher (p < 0.05) than in Fas-L-negative cases. The number of TIA-1-positive lymphocytes in EBV(+) cases was significantly higher than that in the EBV(-) tumors (p < 0.05). The number of apoptotic tumor cells in EBV(+) tumors was significantly lower than in EBV(-) cases (p < 0.01). Our results suggest that in LECS, tumor cells expressing Fas-L may evade the immune attack by killing lymphocytes through the Fas/Fas-L system. However, in EBV(+) LECS tumors, our results indicate that a high number of CTL is associated with a reduction in the number of apoptotic tumor cells. Our findings indicate that the Fas/Fas-L system plays a role in immune evasion of tumor cells in EBV(+) tumors. Int. J. Cancer (Pred. Oncol.) 84:339-343, 1999.

Relationship between Fas-ligand expression on carcinoma cell and cytotoxic T-lymphocyte response in lymphoepithelioma-like cancer of the stomach

The Fas/Fas-ligand (Fas-L) system is involved in the induction of apoptosis and mediates T-cell cytotoxicity. We investigated the Fas/Fas-L system and cytotoxic T lymphocytes (CTLs) in 30 lymphoepithelioma-like cancer of the stomach (LECS) in order to understand the immune evasion of the tumor cells. Epstein-Barr virus (EBV) was detected in 15 cases in 30 LECSs. The expressions of Fas and Fas-L in tumor cells, and TIA-1, CD4, CD8 and CD56 in lymphocytes were examined by immunohistochemical staining. Apoptosis of tumor cells and lymphocytes was detected by the terminal deoxynucleotidyl-mediated dUTP-nick end labeling method (TUNEL). Expression of Fas and Fas-L was detected in tumor cells in 10 and 17 LECS, respectively. CTL consisted predominantly of CD8 (CD8(+) > CD4(+)), whereas natural killer (NK) cells were detected in 4 cases only. In Fas-L-positive tumors, the TIA-1-positive lymphocyte count was significantly lower (p < 0.05) and the number of apoptotic lymphocytes was significantly higher (p < 0.05) than in Fas-L-negative cases. The number of TIA-1-positive lymphocytes in EBV(+) cases was significantly higher than that in the EBV(-) tumors (p < 0.05). The number of apoptotic tumor cells in EBV(+) tumors was significantly lower than in EBV(-) cases (p < 0.01). Our results suggest that in LECS, tumor cells expressing Fas-L may evade the immune attack by killing lymphocytes through the Fas/Fas-L system. However, in EBV(+) LECS tumors, our results indicate that a high number of CTL is associated with a reduction in the number of apoptotic tumor cells. Our findings indicate that the Fas/Fas-L system plays a role in immune evasion of tumor cells in EBV(+) tumors. Int. J. Cancer (Pred. Oncol.) 84:339-343, 1999.

The laminin-derived peptide YIGSR (Tyr-Ile-Gly-Ser-Arg) inhibits human pre-B leukaemic cell growth and dissemination to organs in SCID mice

The YIGSR (Tyr-Ile-Gly-Ser-Arg) laminin beta1 chain sequence has an inhibitory effect on tumour growth and the metastasis of melanoma and fibrosarcoma cells. In the present study, we investigated whether the multimeric YIGSR peptide (Ac-Y16) has an antiproliferative effect and/or prevents the metastasis of human pre-B acute lymphoblastic leukaemia cells (NALM6) in severe combined immune deficient (SCID) mice. In in vitro studies, Ac-Y16 significantly inhibited leukaemic cell colony formation and the invasion of NALM6 cells in a Matrigel-based assay. The tumour growth and leukaemic infiltration in peripheral tissues were also analysed in SCID mice 9 weeks after NALM6, Matrigel and Ac-Y16 were subcutaneously co-injected. The weight of the subcutaneous tumours was significantly suppressed by Ac-Y16 in a dose-dependent manner. Flow cytometry analysis showed that the leukaemic infiltration was significantly inhibited in all organs with 1.5-2.0 mg of Ac-Y16. Leukaemic infiltrations in the brain were inhibited with 0.5 mg of Ac-Y16, and those in brain and bone marrow were also inhibited with 1.0 mg of Ac-Y16. With Ac-S16, a control-scrambled peptide, the only significant inhibition of the leukaemic infiltration was observed in bone marrow at a much higher dose. These data suggest that the multimeric YIGSR peptide can inhibit the tumour growth and metastasis of leukaemic cells and may be useful as a potential therapeutic reagent for leukaemic infiltrations.

Involvement of CYP2E1 as A low-affinity enzyme in phenacetin O-deethylation in human liver microsomes

Phenacetin O-deethylation (POD) exhibits biphasic kinetics in human liver microsomes. Although cytochrome P-450 (CYP) 1A2 is responsible for the high-affinity component of POD, the enzyme(s) that catalyzes the low-affinity reaction is still unknown. We examined the roles of human CYPs in POD by using human liver microsomes and recombinant CYPs from baculovirus-infected insect cells. Of the recombinant CYPs studied, CYP1A2 showed the highest POD activity. CYP1A1, CYP2C19, CYP2D6, CYP2E1, and CYP3A4 also showed POD activity at 500 microM phenacetin. K(M) values of recombinant CYP1A2 and CYP2E1 (28 +/- 2 microM and 785 +/- 125 microM, respectively) were similar to those of the high- and low-affinity components of POD in pooled human liver microsomes (15 +/- 5 and 894 +/- 189 microM, respectively). Fluvoxamine (10 microM) and anti-CYP1A2 antibodies potently inhibited POD activity at 500 microM phenacetin in pooled human liver microsomes to 22.8 and 34.2% of controls, respectively. CYP2E1 inhibitors diethyldithiocarbamate and aniline also reduced POD activity. The combination of fluvoxamine (10 microM) and aniline (1 mM) further inhibited the residual POD activity not inhibited by fluvoxamine alone. Microsomal POD activity in 12 human livers in the absence of fluvoxamine was correlated with immunoquantified CYP1A2 levels (r = 0.961, p <.001) and, in the presence of 10 microM fluvoxamine, was correlated with immunoquantified CYP2E1 levels (r = 0.589, p <.01) or chlorzoxazone 6-hydroxylase activity (r = 0.823, p <.001). These results suggest that CYP2E1 is responsible for the low-affinity component of POD in human liver microsomes.

The residual epiretinal membrane after vitrectomy for macular hole

BACKGROUND

We retrospectively observed idiopathic macular holes in 63 eyes using a scanning laser ophthalmoscope, in order to study the relation between postoperative epiretinal membranes and closure of macular holes following vitrectomy.

METHODS

The eyes were classified into three groups based on the degree of the postoperative epiretinal membranes. Group I consisted of 23 eyes with no epiretinal membrane remaining on the retina after vitrectomy. Group II consisted of 20 eyes in which epiretinal membranes were observed on the retina, but separate from the edge of the macular hole. Group III consisted of 20 eyes in which epiretinal membranes were observed at the edge of the macular hole. Using these three groups, we studied how postoperative epiretinal membranes were related to the closure of macular holes.

RESULTS

All macular holes (100%) in groups I and II were closed following vitrectomy. In group III, 5 (25.0%) of 20 eyes had complete closure and 13 eyes (65.0%) had incomplete closure of the macular hole, while 2 eyes (10.0%) had re-opening of initially closed macular holes several months after vitrectomy.

CONCLUSION

Residual postoperative epiretinal membranes at the edge of macular hole are responsible for primary failure of vitrectomy. Removal of epiretinal tissues around the macular hole is important for macular hole to be closed following vitrectomy.

[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.