Prospective study of mother-to-infant transmission of hepatitis C virus

BACKGROUND

Mother-to-infant transmission of hepatitis C virus (HCV) could become the main route of HCV infection in the future because there are no methods available to prevent vertical infection. The aim of this study was to determine the incidence of mother-to-infant transmission in infants born to mothers who tested positive for anti-HCV antibodies and to elucidate associated risk factors for transmission.

METHODS

Screening was conducted for 16,800 pregnant women with an anti-HCV antibodies test, and 154 mothers were positive. From the positive group 141 mothers were enrolled in the study and their 147 infants were followed from birth for serum alanine aminotransferase activity, anti-HCV antibodies and HCV RNA. HIV infection was tested in 73 of 141 mothers, all of whom were negative.

RESULTS

Thirty-three infants were dropped from the study because they were followed for <6 months or were not tested adequately. Of the 114 infants finally evaluated 9 (7.8%) had detectable HCV RNA. The transmission rate was not influenced by the mode of delivery [vaginal delivery, 8 of 90 vs. cesarean section, 1 of 24 (P = 0.396)] or by the type of feeding [9 of 98 for breast-fed infants vs. 0 of 16 for formula-fed infants (P = 0.243)]. All infected infants were born to mothers who had HCV viremia at the delivery (P = 0.040) and to those with a high viral load (P = 0.019).

CONCLUSIONS

Our prospective study showed that the transmission rate of mother-to-infant HCV infection was 7.8% in anti-HCV antibody-positive mothers. Risk was related to the presence of maternal HCV viremia at delivery and a high viral load in the mothers.

Extrasolar planets

The first known extrasolar planet in orbit around a Sun-like star was discovered in 1995. This object, as well as over two dozen subsequently detected extrasolar planets, were all identified by observing periodic variations of the Doppler shift of light emitted by the stars to which they are bound. All of these extrasolar planets are more massive than Saturn is, and most are more massive than Jupiter. All orbit closer to their stars than do the giant planets in our Solar System, and most of those that do not orbit closer to their star than Mercury is to the Sun travel on highly elliptical paths. Prevailing theories of star and planet formation, which are based on observations of the Solar System and of young stars and their environments, predict that planets should form in orbit about most single stars. However, these models require some modifications to explain the properties of the observed extrasolar planetary systems.

Two cases of persistent hyperinsulinemic hypoglycemia that showed spontaneous regression and maturation of the Langerhans islets

Near-total pancreatectomy has been recommended as the treatment for persistent hyperinsulinemic hypoglycemia (PHH) in infants. However, recently there has been a report described that one third of 95% pancreatectomy failed to prevent hypoglycemia and more than two thirds had diabetes ultimately. The authors experienced 2 cases of PHH, which raise a query about the extensive pancreatectomy. Case 1: A female patient who manifested PHH shortly after birth underwent less extensive pancreatectomy twice at age 2 months and 8 years. After each operation, her clinical symptoms regressed, and she became free from the disease eventually. Histologic findings showed nesidioblastosis in which the islets clearly matured. Case 2: A male infant with PHH had an absolute indication for pancreatectomy. However, after a meticulous control of the blood glucose level with parenteral nutrition followed by continuous enteral nutrition feeding combined with medication, he became free from the disease. The current cases show there exist cases of PHH in which the islets mature and symptoms regress spontaneously. Therefore, we conclude near-total pancreatectomy is not always the treatment of choice. As an alternate strategy, long-term controlled feeding and medication combined with or without less extensive pancreatectomy should be considered with the expectation of spontaneous regression.

Four cases of bleeding diathesis in children due to congenital plasminogen activator inhibitor-1 deficiency

Congenital plasminogen activator inhibitor-1 (PAI-1) deficiency is an extremely rare disorder characterized by a bleeding diathesis that begins in childhood due to hyperfibrinolysis as a result of decreased PAI-1 activity. We now present 4 unrelated pediatric cases of congenital PAI-1 deficiency. All 4 patients had a history of recurrent episodes of subcutaneous bleeding beginning in early childhood. These episodes were characterized by abnormal prolonged bleeding after trauma, tooth extraction, and surgical procedures, as well as by rebleeding following initial hemostasis. The 2 female patients both had symptoms compatible with hypermenorrhea. The family history was positive in 2 of the 4 patients. Hemostatic screening studies in all 4 patients revealed no abnormalities. Testing for factor XIII antigen, von Willebrand factor antigen, ristocetin cofactor activity, alpha(2)-plasmin inhibitor (alpha2PI) activity, and plasminogen activity was normal. The euglobulin lysis times were shortened in all cases as compared with those in normal control subjects. None of the patients had elevated tissue plasminogen activator (tPA) antigen levels, but PAI activity was markedly decreased in all cases. Three of the patients also had reduced levels of PAI-1 antigen. There tended to be a reduction in tPA-PAI-1 complex in all cases. In addition, 2 patients had elevated PIC (plasmin-alpha2PI complex). Tourniquet tests were performed in 2 patients, with no appreciable rise in PAI-1 activity or PAI-1 antigen levels. The administration of tranexamic acid clearly improved hemorrhagic symptoms in these patients. We considered PAI-1 deficiency to be the likely etiology of the congenital bleeding diatheses in these 4 cases.

Effects of lithium on the pharmacokinetics of valproate in rats

Combined treatment with lithium and valproate has been used for bipolar disorder. However, the studied interaction between these two drugs has not been fully investigated. We therefore examined the effects of lithium on the pharmacokinetics (plasma disappearance, metabolism and urinary excretion) of valproate in rats. Lithium (2 mEq kg(-1)) was administered intraperitoneally twice a day for ten days. Plasma disappearance curves of valproate (50 mg kg(-1), i.v.), valproate-metabolizing activities of UDP-glucuronosyltransferase (UGT) and cytochrome P450 (CYP) in liver microsomes and urinary excretion of free valproate and valproate-glucuronide were examined. The metabolizing activity of UGT and CYP were determined by enzyme assays and a fluorescence polarization immunoassay system. Urinary valproate-glucuronide was obtained using this system by subtracting the free level from total level, which was determined after deconjugating the sample with heat and NaOH. The half-life of plasma disappearance of valproate was 25% reduced by lithium pretreatment (0.428 +/- 0.031 h with repeated lithium pretreatment vs 0.578 +/- 0.062 h for controls). The valproate-metabolizing activity of UGT and CYP were not altered by lithium although lithium increased the urinary excretion of valproate-glucuronide. In conclusion, lithium pretreatment causes a decrease in plasma valproate levels and an increase in urinary excretion of valproate-glucuronide in rats.

[A two-year follow-up of zidovudine plus lamivudine combined with indinavir in antivival naive HIV-infected patients]

Efficacy of a 3-drug combination (Zidovudine (AZT) + Lamivudine (3TC) + Indinavir (IDV)) has been evaluated in 17 anti-viral naive patients with HIV infection for 24 months. Our genotypic resistance assay was able to analyze more than 80% of the patients whose viral load (VL) was over 3,000 copies/ml. This therapy was continued in 11 patients (65%) for 24 months. Among them, VL was undetectable (VL < 400 copies/ml) in patients at 24 month (47% by intent-to-treat, 72% by on treatment). Of the 11 patients, a 3TC resistance-related mutantion was detected in only one case. The therapy was discontinued in 6 cases. Main reasons of the discontinuation were side effects. However, if the therapy was switched to other combinations when VL was undetectable, VL remained undetectable in 5 cases at 24 month.

Reduction in interleukin-2-producing cells but not Th1 to Th2 shift in moderate and advanced stages of human immunodeficiency virus type-1-infection: direct analysis of intracellular cytokine concentrations in CD4+ CD8- T cells

Previous studies have suggested that CD4+ T lymphocytes shift from the Th1 type to the Th2 type during disease progression in patients with the human immunodeficiency virus type-1 (HIV-1). In the present study, we used a modified method that allowed a direct measurement of intracellular cytokines in CD4+ CD8- T cells. A total of 48 HIV-1-infected (HIV+) and 16 HIV-1-uninfected (HIV-) individuals were studied. The percentages of CD4+ CD8- T cells producing interleukin-2 (IL-2), interferon-gamma (IFN-gamma), interleukin-4 (IL-4), or interleukin-5 (IL-5) in HIV+ and HIV- subjects were 23.6% versus 34.9% (P < 0.01), 13.7% versus 13.2%, 1.3% versus 1.0%, and 1. 2% versus 0.9%, respectively. The population of IL-2-producing cells decreased proportionately with reductions in CD4 counts (< 200/mm3, 200-500/mm3, and > 500/mm3 to 18.0%, 23.5%, and 30.5%, P < 0.05, respectively). There was an inverse correlation between the percentage of IL-2-producing cells and plasma viral load (r = - 0. 446, P < 0.05). However, the percentages of CD4+ CD8- T cells producing other cytokines were not different between HIV+ and HIV-. Our cross-sectional study demonstrated a decrease in IL-2-producing cells but not the Th1 to the Th2 shift in the CD4+ CD8- T cell population in the moderate and advanced stages of HIV-1-infection.

[Usefulness of MT-2 assay to decide when to start anti-HIV therapy]

It is well known that the emergence of syncytium inducing (SI) variant correlates accelerated CD4 decline and disease progression during the course of HIV infection. We have conducted a clinical study to investigate whether or not detection of SI by MT-2 cells (MT-2 assay) can be a clinical marker to decide when to start anti-HIV therapy since 1995. We examined 483 blood samples obtained from 172 HIV-infected patients by the MT-2 assay. SI was detected from 20 patients. There were five untreated patients whose CD4 counts were 300/microliter or more. Anti-HIV combination therapies were started soon after detection of SI in all of them. We have followed their clinical courses for more than 4 years, so far, in three of them. Their CD4 counts and clinical courses were both stable. In contrast, in another patient who could not receive any anti-HIV therapy even though SI positive, decline of CD4 was very rapid (200/microliter/year) and the disease progressed to AIDS within one year as like other SI positive cases before the era of several approved anti-HIV drugs. According to these distinct prognosis, the MT-2 assay might be a useful clinical marker for deciding anti-HIV therapy at least in our limited cases.

Genetic alterations in the JAG1 gene in Japanese patients with Alagille syndrome

Alagille syndrome (AGS) is a congenital anomaly syndrome that affects liver, heart, pulmonary artery, eyes, face, and skeleton. Recently, mutations of the JAG1 gene, which encodes a ligand for the Notch receptor, have been identified in AGS patients. We investigated the JAG1 gene for genetic alterations in eight Japanese AGS patients, using fluorescence in situ hybridization (FISH), single strand conformation polymorphism (SSCP) analysis, and direct sequencing. Subtle genetic alterations were identified in six of the eight patients, including three frameshift mutations, two splice donor mutations, and one nonsense mutation. All alleles with identified mutations can be expected to produce non-functional truncated proteins without a transmembrane domain. There was no apparent correlation between the genotypes of the patients and their affected organs, although the phenotypes of the patients with mutations at the splice donor site were found to be less severe.

Preparation of N-alkylated 5-oxo-3-carboxamyl-1,4-thiazinanes on solid support

A general method was developed to generate six-membered cyclic thiazinanes on solid support. Three diversity sites were introduced into this scaffold using primary amines, aldehydes, and 2-bromoalkanoic acids. The methodology to prepare individual cyclic thiazinanes as well as combinatorial libraries of these compounds is described.

Acute effects of griseofulvin on the pharmacokinetics and pharmacodynamics of warfarin in rats

It has been reported that prothrombin time (PT), which is prolonged by warfarin, is reduced when patients on warfarin also take griseofulvin repeatedly. We investigated the cause of the drug interaction and the initial effects of griseofulvin on warfarin pharmacokinetics. Total cytochrome P-450, and the activities of aminopyrine N-demethylase, aniline p-hydroxylase and 7-ethoxycoumarin O-deethylase, after repeated administration of griseofulvin (100 mg/kg orally daily for 5 days) were examined. Acute effects of single doses of griseofulvin (100 mg/kg) on coagulation activity (prothrombin time) and warfarin pharmacokinetics after administration of warfarin were also studied. Repeated administration of griseofulvin induced warfarin-metabolizing enzymes. In contrast, a single administration of griseofulvin increased prothrombin time and serum warfarin concentrations. The activity of a warfarin-metabolizing enzyme (7-ethoxycoumarin O-deethylase) was reduced when griseofulvin was added to rat liver microsomes. The results suggest that reduced warfarin action after repeated administration of griseofulvin may be due to induction of warfarin-metabolizing enzymes, but that there is also an initial increase in warfarin action.

Identification of highly selective inhibitors of collagenase-1 from combinatorial libraries of diketopiperazines

Thiol-containing diketopiperazines have been recently identified as novel heterocyclic inhibitors of matrix metalloproteinase (MMPs). The compounds described had similar activities against the MMPs collagenase-1 and gelatinase-B. An inhibitor that showed greater than 10-fold selectivity for collagenase-1 over gelatinase-B was desired. Previously published work with peptidyl hydroxamates and thiols indicated that while preparing gelatinase selective inhibitors was straightforward, there was not an obvious route to selective inhibitors of collagenase-1. Combinatorial libraries were prepared and evaluated for their ability to inhibit collagenase-1 and gelatinase-B substrate hydrolysis. A method for estimating the IC50 values of compounds generated by high-throughput parallel synthesis aided in the identification of compounds with the desired properties. We have found that thiol diketopiperazines derived from nitrophenylalanine are both potent and selective inhibitors of collagenase-1. In addition, we have demonstrated that combinatorial chemistry can be utilized to identify molecules with a desired selectivity profile without access to the traditional tools of rational drug design.

Active HIV-1 redistribution and replication in the brain with HIV encephalitis

The central nervous system (CNS) is of particular importance in human immunodeficiency virus type 1 (HIV-1) infection. First, the CNS may be difficult to access for anti-retroviral treatment and may become a sanctuary for residual viruses. Second, HIV-1 infection may lead to AIDS dementia complex (ADC) culminating in HIV-1 encephalitis. In order to examine the pattern of drug resistance and the role of encephalitis in enhancing viral redistribution to the CNS, we compared pol gene quasispecies of the spleen and brain in two patients with and two patients without HIV-1 encephalitis, who had been treated with zidovudine (AZT). Although a variable degree of AZT resistance was noted in both the spleen and brain of all patients, phylogenetic analysis indicated that quasispecies developed rather independently in the systemic circulation (spleen) and CNS (brain) of patients without HIV-1 encephalitis, while similar pol gene sequences were obtained from the two compartments of patients with HIV-1 encephalitis. env gene V3 region of patients with HIV-1 encephalitis showed distinct quasispecies in the spleen and brain. Our results suggest that HIV-1 redistribution to CNS is more active in cases with encephalitis and that HIV-1 distributed late to CNS grow actively under certain selective pressure exerted on the V3 region of the env gene.

[Investigation of a new p24 antigen detection system by the chemiluminescence-enzyme-immuno-assay]

We investigated a new p24 antigen detection system by the chemiluminescence-enzyme-immuno-assay (CLEIA) and compared it with the conventional antigen-kits (A; Abbott, B; Coulter). The detection limit of CLEIA, A, and B were 4.3 pg/ml, 11.3 pg/ml, and 5.6 pg/ml, respectively. When the patient's sera and panel sera were examined by the three method, compatible results with the detection limit were obtained. CLEIA can be completed within 35 min, and is performed by an automatic system, which can treat many samples at one time. Therefore, this system is more suitable for screening of donor blood because of the shortening of the window period.

Evaluation of highly sensitive thyrotropin assay for detecting thyroid diseases in neonatal screening: preliminary studies

TSH concentrations in dried blood samples on filter paper were determined by a conventional enzyme-linked immunosorbent assay (ELISA), used for routine neonatal screening for primary hypothyroidism, and a highly sensitive bioluminescence ELISA (BL-ELISA) using firefly luciferase to examine whether central hypothyroidism and hyperthyroidism can be efficiently detected as cases of primary hypothyroidism. Samples were obtained from 3 patients with congenital central hypothyroidism, 5 patients with congenital primary hypothyroidism, 6 patients with hyperthyroidism, 31 neonatal babies with low birth weight (premature babies) and 242 newborn babies with normal birth weight from the general population (normal babies). The TSH values were low in central hypothyroidism and hyperthyroidism. Their deviations from the mean TSH value for normal babies by the BL-ELISA method (-3.12 SD and -4.79 SD in central hypothyroidism and hyperthyroidism respectively) were greater than those by the ELISA method (-2.00 SD and -2.97 SD respectively). The TSH values were high in primary hypothyroidism and normal in premature babies while deviations were the same when BL-ELISA and ELISA were used. These findings indicate that the highly sensitive TSH assay (BL-ELISA) can be used for detecting both primary and central hypothyroidism as well as hyperthyroidism in neonatal screening.

Malonyl alpha-mercaptoketones and alpha-mercaptoalcohols, a new class of matrix metalloproteinase inhibitors

A novel series of matrix metalloproteinase (MMP) inhibitors is described. Incorporation of a terminal alpha-mercaptoketone or alpha-mercaptoalcohol in the zinc binding domain of a series of inhibitors led to compounds exhibiting low nanomolar activity against collagenase-1 (MMP-1), stromelysin (MMP-3), and gelatinase-B (MMP-9).

HIV type 1 V3 variation dynamics in vivo: long-term persistence of non-syncytium-inducing genotypes and transient presence of syncytium-inducing genotypes during the course of progressive AIDS

We performed a population-based sequence analysis of the envelope V3 region of human immunodeficiency virus type 1 (HIV-1) in two infected hemophiliacs. The study was conducted over 6-9 years, extending from the asymptomatic phase to AIDS. In both patients, serial analysis showed that the V3 population at the initial stage consisted exclusively of putative non-syncytium-inducing (NSI) genotypes. Several of these clones continued to be present without change for many years until the terminal stage and often represented the dominant species in the population at each time interval. On the other hand, syncytium-inducing (SI) genotypes were initially absent but appeared shortly before severe depletion of CD4+ T cells and their proportion in the population appeared to correlate with the viral load. In sharp contrast to NSI genotypes, SI genotypes displayed a significantly shorter presence. Thus, rapid gross population changes were found in SI genotypes, which were particularly frequent in the asymptomatic phase and less frequent in the terminal stage. Furthermore, the ratio of nonsynonymous nucleotide substitutions per synonymous substitutions in the V3 region in SI genotypes was higher than the corresponding value of NSI genotypes and the phylogenetic tree analysis revealed that a longer branch length was observed in SI genotypes than in NSI genotypes. These results suggest that there might be a stronger pressure for selection on SI viruses than on NSI viruses during the high CD4 counts on the contrary to the fact that emergence of SI genotypes was well correlated with the rapid decline of CD4 count.

[Home oxygen therapy (HOT) in patients with pulmonary tuberculosis sequelae--comparison between patients medically treated and those surgically treated]

In Japan there are about 40,000 patients under home oxygen therapy (HOT), of whom about 30 to 40% are pulmonary tuberculosis sequelae (TBS). These patients can be divided into three groups depending on the treatments they had, Group 1: those who had medical treatments only, Group 2: those who had artificial pneumothorax, and Group 3: those who had thoracoplasties or other surgical treatments. The purpose of this study was to observe the distributions and possible differences in the survival rates among these groups. The study included 1537 patients with TBS under HOT followed at National Hospitals and Sanatoriums nationwide in Japan. In 819 patients the treatments were specified and of those 354 were in Group 1, 29 in Group 2, and 436 in Group 3, so that the proportion of surgically treated patients in PTS was estimated between 28.4% (436/ 1537) to 53.2% (436/819). The ages at the onset of tuberculosis, at the start of HOT and the intervals in between were 36.6, 66.2 and 29.8 in Group 1, and 26.8, 65.5, and 38.1 in Group 3 respectively. Though the ages at the start of HOT were the same, those at the onset of tuberculosis were about ten years younger in Group 3 than in Group 1. Comparing Group 1 and 3, the survival rates after the initiation of HOT (Kaplan-Meier method) was better in Group 2 (surgically treated) than in Group 1 (medically treated). It is speculated that the reason could be a better preservation of the function of the remaining lung in the surgically treated and a higher incidence of obstructive impairments in the medically treated patients.

Purification and characterization of rhesus monkey liver amido hydrolases and their roles in the metabolic polymorphism for E6123, a platelet-activating factor receptor antagonist

We previously showed that a polymorphism for E6123 [(S)-(+)-6- (2-chlorophenyl)-3-cyclopropanecarbonyl-8,11-dimethyl-2,3,4,5- tetrahydro-8H-pyrido[4',3':4,5]thieno[3,2-f][1,2,4]triazolo[4,3-a] [1,4]diazepine] metabolism exists only in rhesus monkeys. In the present study, we purified, from rhesus monkey hepatic microsomes, three amido hydrolases that are involved in the metabolic polymorphism. Two forms of amido hydrolase from an extensive metabolizer and one from a poor metabolizer were purified by Q-Sepharose Fast Flow, Red A-agarose, octylamino-Sepharose 4B, and hydroxyapatite-Ultrogel chromatography, after solubilization with Lubrol. The three purified enzymes had the same molecular mass (47 kDa), and their amino-terminal amino acid sequences were identical. The enzymes were different from various known carboxylesterases in terms of substrate specificity, molecular mass, and amino-terminal amino acid sequence. They resembled arylacetamide deacetylase from human hepatic microsomes with respect to molecular mass and amino-terminal amino acid sequence. The KM values of the high and low affinity enzymes in the extensive metabolizer and the sole enzyme in the poor metabolizer were 37.6, 73.0, and 76.5 microM, respectively. The Vmax values were 3312.4, 504.8, and 427.9 pmol/min/mg of protein, respectively. The high affinity enzyme in extensive metabolizer appears to be quite distinct, whereas the low affinity enzyme in extensive metabolizer in similar or identical to the sole enzyme in poor metabolizer. Thus, the metabolic polymorphism in rhesus monkey may depend upon the existence of the high affinity enzyme in extensive metabolizer.

Cloning and nucleotide sequence of a leaf ferredoxin-nitrite reductase cDNA of rice

A ferredoxin-nitrite reductase (EC 1.7.7.1) cDNA was isolated and sequenced from a lambda gt 11 cDNA library constructed from nitrate-induced greening shoots of rice (Oryza sativa L.) seedlings. The nucleotide sequence of the cDNA clone contains an open reading frame of 1788 nucleotides. There exists a strong bias for the third codon usage of G/C (95.5%) as in the case of the maize enzyme. The deduced amino acid sequence shows an overall homology to the maize (81%) and the dicot enzymes (70-74%), suggesting that the primary structure of ferredoxin-nitrite reductase is highly conserved in higher plants.