Comparison of the sensitivity of NAT using pooled donor samples for HBV and that of a serologic HBsAg assay.

BACKGROUND: Studies were conducted using samples from early and late-stage HBV-infected persons to determine the pool size at which PCR had better sensitivity than a sensitive HBsAg chemoluminescence immunoassay (CLIA-HBsAg). STUDY DESIGN AND METHODS: HBV seroconversion panels were tested for HBsAg by CLIA and for HBV DNA by nested PCR (95% hit rate: 100 copies/mL); PCR was carried out at various dilutions. HBV serologically positive samples that were detected from the simultaneous screening of 540,161 routine whole-blood donations using CLIA-HBsAg and agglutination assays were also characterized for additional markers of HBV infection. RESULTS: In 9 of 10 HBV seroconversion panels, PCR had better sensitivity than CLIA-HBsAg at dilutions of 1-in-25 or lower. Of 65 CLIA-only confirmed-positive donor samples (agglutination assay-negative), 8 represented early infection, 2 of which were PCR positive at a 1-in-50 dilution but negative at a 1-in-100 dilution. Only 2 of 47 samples from probable late-stage HBV infection that were positive on CLIA only were PCR positive with 0.1-mL sample volume and the S-region primer; the remaining 45 samples required a 1.0-mL sample input and C-region primer for increased PCR positivity. The remaining 10 CLIA-only confirmed-positive donor samples were from HBV vaccine recipients. None of the 12 CLIA- and HBsAg-negative donor samples that were strongly anti-HBc reactive could be detected by PCR at any dilution; all 12 were PCR positive when undiluted, but 4 required a 1.0-mL input volume for PCR positivity. CONCLUSION: For the detection of samples representing early-stage HBV infection, PCR at dilutions of 1-in-25 or lower (equivalent to a pool of < or =25 members) had greater sensitivity than CLIA-HBsAg. In contrast, samples from late-stage HBV infection were detected by PCR only with undiluted samples (0.1-mL or 1.0-mL input volumes), regardless of CLIA-HBsAg reactivity. Therefore, although NAT using minipools of 25 donations or less may be effective for the detection of early-stage HBV infection, it may not be effective for the detection of persistent HBV infection.

Identification of a novel allele HLA-B*7805 in a Japanese female.

A new HLA-B*78 allele, B*7805, was identified in a healthy Japanese female. The results of her serological HLA class I typing showed an unusual Bw4/Bw6 pattern with strongly positive reactivity to anti-Bw6, i.e. A24, -, B52, -, Bw4, Bw6. In DNA typing, she was typed as A*24, -, B*52, B*78-like, Cw1202, -, (Bw4, Bw6). Cloning and sequencing of exon 2 and exon 3 of her B locus genes revealed a new allele B*7805. The cloned B*7805 differed from B*78021 by three nucleotide substitutions in exon 2 at position 259 (A to G), 261 (C to G) and 272 (A to C), and contained sequences defining Bw6 motif in the region of codon 77 to 83.

[Immunogenetic factors influencing HBV carrier state, the seroconversion and the development of chronic liver disease].

In order to investigate the immunogenetic factors associated with hepatitis B virus (HBV) carrier state, the HBe seroconversion and the development of chronic liver disease, HLA typing were performed in 278 asymptomatic HBV carriers (ASC) and 110 patients with chronic B type hepatitis (CH). HLA typing was also performed in 178 vaccinees who had received hepatitis B vaccine. The significantly decreased frequencies of DR1 and DRw13 were found in ASC, CH and non-responders to HB vaccine. This suggests that DR1 and DRw13 may be associated with the elimination of HBV. The frequency of DR4.2 was increased in ASC, but decreased in CH. The seroconversion rate of DR4.2 positive CH as well as ASC was high. Therefore DR4.2 may have relevance to the seroconversion from HBeAg to anti-HBe.

General pharmacology of beraprost sodium. 1st communication: effect on the central nervous system.

Beraprost sodium (sodium (+/-)-(1R*,2R*,3aS*,8bS*)-2,3,3a,8b-tetrahydro-2- hydroxy-1-[(E)-(3S*)-3-hydroxy-4-methyl-1-octen-6-ynyl]-1H- cyclopenta[b]benzofuran-5-butyrate, TRK-100) is an orally active epoprostenol (prostaglandin I2, PGI2) analogue. Its effect on the central nervous system (CNS) was studied. 1. When orally administered in mice, beraprost sodium at 0.3 mg/kg caused a flush of skin, a suppression of spontaneous motility, and a fall of body temperature. At 1 mg/kg and more, it showed obvious sedation, prolongation of hexobarbital hypnosis, and analgesic action in acetic acid-induced writhing test. However, even at 3 mg/kg beraprost sodium neither induced ataxia nor had anticonvulsant activity. Hypothermia was also observed in rabbits at 1 mg/kg (p.o. and i.v.). 2. When intravenously administered, beraprost sodium exerted long-lasting action on the CNS, while its pharmacological effects resembled those of PGI2. 3. Oral administration of beraprost sodium did not inhibit aggregation toxicity induced by methamphetamine (20 mg/kg i.p.) in mice. Beraprost sodium at doses higher than 1 mg/kg enhanced aggregation toxicity induced by methamphetamine (5 mg/kg i.p.), while intracerebral ventricular administration of beraprost sodium failed to enhance it. 4. In rat spinal reflex, intravenous administration of beraprost sodium (0.1 mg/kg) slightly enhanced monosynaptic reflex and at a high dose (1 mg/kg) suppressed polysynaptic reflex. 5. In the rabbit EEG, intravenous administration of beraprost sodium at a high dose (1 mg/kg) showed some effects such as the continuous pattern of wakefulness and a fall in power of the EEG.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacological studies of mabuterol, a new selective beta 2-stimulant. III: Effects on the central nervous system, striated muscle and carbohydrate and lipid metabolism.

Effects of dl-1-(4-amino-3-chloro-5-trifluoromethyl-phenyl)-2-tert.-butylamino-etha nol hydrochloride (mabuterol) on the central nervous system, the striated muscle and the carbohydrate and lipid metabolism were investigated in comparison with those of isoprenaline and salbutamol. Mabuterol caused the following changes in behavior: increased touch response (10 mg/kg p.o.), decreased spontaneous movement and ptosis (30 and 100 mg/kg p.o., resp.), observed for 240-300 min. Mabuterol (5 mg/kg p.o. and 2.5 mg/kg s.c.) prolonged the sleeping time induced by hexobarbital Na, but not dose-dependently. Mabuterol depressed reactive movement at 80 mg/kg p.o. and 40 mg/kg s.c. in the rotarod test, at 160 mg/kg p.o. and 40 mg/kg s.c. in the traction test and at 200 mg/kg p.o. and 160 mg/kg s.c. in the inclined plane test in mice, whereas isoprenaline and salbutamol were almost ineffective. Analgesic activity of mabuterol was found in the acetic acid writhing test but not in the bradykinin-induced nociception test. An anticonvulsive effect was not observed. Mabuterol (10 mg/kg i.v.) produced a change in the spontaneous EEG of one of three rabbits, showing synchronization of cortical activity with sedation. Equipotent dose (i.v.) ratios of mabuterol to isoprenaline were 10.2, 30 and 133 in the depression of incomplete tetanic contraction of cat soleus muscle, hypotensive effect and tachycardia respectively, whereas neither indirect nor direct electrical stimulation induced contraction of diaphragm and gastrocnemius muscle was affected. Equipotent dose (s.c.) ratios of mabuterol to isoprenaline were 2.07, 4.64 and 3.21 in increasing plasma levels of glucose, lactic acid and free fatty acids respectively. Mabuterol caused no remarkable change in myocardial glycogen content.