Comparison of HCV RNA Levels by Branched DNA Probe Assay and by Competitive Polymerase Chain Reaction to Predict Effectiveness of Interferon Treatment for Patients with Chronic Hepatitis C Virus

To compare hepatitis C virus (HCV) RNA levelsdetermined by branched DNA probe assay and bycompetitive polymerase chain reaction (PCR) aspredictive markers of the response to interferon fortreatment of patients with chronic HCV infection, westudied data on 140 patients treated for six months withnatural interferon-alpha. Serum samples were tested forHCV RNA by PCR. HCV RNA was grouped into four genotypes by PCR with type-specific primers,and HCV RNA level was measured by branched DNA probeassay and by competitive PCR. HCV RNA was detected inall patients prior to initiation of the treatment. A complete response, sustained elimination ofHCV RNA, occurred in 51 patients (36.4%). With multiplelogistic regression analysis assessment, when usingcompetitive PCR, a low level of HCV RNA (P < 0.0001), younger age (P = 0.0054) and genotype 2a and 2b(P < 0.0158) were significant predictive markers fora complete response to interferon treatment. When usingbranched DNA probe assay, a low level of HCV RNA (P < 0.0001) and age (P = 0.0089) werepredictive markers, but genotype was not. The branchedDNA probe assay had a narrower linear range forquantitation of HCV RNA level than competitive PCR. In conclusion, HCV RNA level determined bybranched DNA probe assay proved to be useful forprediction of effects of interferon and it is costeffective as a marker of complete response to interferontreatment for patients with chronic HCVinfection.     

The blood-brain barrier and selective vulnerability in experimental thiamine-deficiency encephalopathy in the mouse

The integrity of the blood-brain barrier (BBB) is an important aspect of normal central nervous system (CNS) function. Recently, it was shown that the BBB breakdown is one of the predisposing factors in the pathogenesis of thiamine-deficiency encephalopathy. The result is discussed along with some reviews on previous research of BBB integrity in thiamine deficiency.     

Seroepidemiology of TT Virus Infection and Relationship Between Genotype and Liver Damage

TT virus (TTV) has been identified in patients with posttransfusion hepatitis of unknown etiology and is thought to be a new hepatitis virus. We determined the extent of TTV infection in the Japanese general population and the relationship between TTV DNA genotype and liver damage. In 1998, we tested 847 serum samples for TTV. TTV DNA was assayed by a nested polymerase chain reaction and classified into three different genotypes and eight subtypes. TTV DNA was detected in 25.3% and 32.4% of the inhabitants of the two areas studied, respectively. The genotype distribution was similar in both areas. G1, G2, and G3 were 60%, 20%, and 5%, respectively. Of the 20 subjects with TTV DNA alone and elevated serum ALT levels, 18 were G1, one was G2, and one was G3. TTV infection is endemic in the Japanese general population studied. The main TTV genotype, G1, may be related to the ensuing liver damage.     

Prevalence of hepatitis C virus infection among female prostitutes in Fukuoka,Japan

To assess the risk of sexual transmission of hepatitis C virus (HCV), we surveyed female prostitutes to determine the prevalence of antibody to HCV (anti-HCV) and HCV RNA. Anti-HCV was examined with a second generation anti-HCV test employing a passive hemagglutination assay. HCV RNA was detected by two-stage polymerase chain reaction with primers deduced from the 5′-noncoding region of the HCV genome. All studies were performed in Fukuoka, Japan, from 1989 through 1992 and all subjects were Japanese and had no history of intravenous drug abuse. The prevalence of anti-HCV was significantly higher in the prostitutes (10.1%; 61/604) than in the controls (female blood donors; 0.8%; 52/6632) (P<0.001). HCV RNA was found in 73.2% of the anti-HCV-positive prostitutes. The prevalence of anti-HCV among prostitutes increased with the number of years spent in prostitution (P<0.05). Prostitutes with a history of syphilis had a higher prevalence of anti-HCV than those with no history of syphilis, irrespective of the number of years in prostitution. In a longitudinal study of 244 prostitutes, 2 of the 218 initially seronegative subjects showed anti-HCV and HCV RNA over the study period of 3 years. These two persons had no history of percutaneous exposure. Sexual transmission of HCV presents a risk for female prostitutes.     

Interaction Between Proteoglycans and α-Elastin in Construction of Extracellular Matrix of Human Yellow Ligament

One type of large proteoglycan and three types of small proteoglycans (decorin, decorin-subtype, and biglycan) were purified by chromatography, and α-elastin was isolated by alkali treatment from human yellow ligaments taken at the time of operation. The interaction of the proteoglycans with immobilized α-elastin on a sensor was analyzed by surface plasmon resonance, and we confirmed that each of the small proteoglycans exhibited a specific binding to α-elastin. The binding sites of small proteoglycans were contained in the protein cores. In addition, the differences in the interaction of the small proteoglycans with α-elastin of normal and ossified ligaments were compared. The interactions of the small proteoglycans with α-elastin of the ossified ligaments were lower than those with α-elastin of the normal ligaments. In the ossified ligaments, neodesmosine, one of the cross-linking amino acids, was significantly less than in the normal ligaments (p < .05).     

Acetylcholine receptors in dissociated nucleus basalis of Meynert neurons of the rat

Electrical and pharmacological properties of acetylcholine (ACh)-induced currents in neurons dissociated from the nucleus basalis of Meynert (nBM) of immature (2-week-old) rats were investigated with the whole-cell mode of the patch-clamp technique. At a holding potential (V_H) of −50 mV, ACh (10⁻⁴M) evoked a transient inward current mimicked by nicotine (I_nACh), followed by a sustained outward current mimicked by carbamylcholine (I_mACh). The K_D values were 1.2 × 10⁻⁴ M for I_nACh) and 8.7 × 10⁻⁷ M for I_mACh. The reversal potenial of I_mACh was close to E_K. The I_mACh was determined to be elicited via the M₂ muscarinic receptor, based on the differences in sensitivity to muscarinic antagonists such as pirenzepine and AF-DX-116.     

Miniature release events of glutamate from hippocampal neurons are influenced by the dystonia-associated protein torsinA

TorsinA is an evolutionarily conserved AAA+ ATPase, and human patients with an in‐frame deletion of a single glutamate (ΔE) codon from the encoding gene suffer from autosomal‐dominant, early‐onset generalized DYT1 dystonia. Although only 30–40% of carriers of the mutation show overt motor symptoms, most experience enhanced excitability of the central nervous system. The cellular mechanism responsible for this change in excitability is not well understood. Here we show the effects of the ΔE‐torsinA mutation on miniature neurotransmitter release from neurons. Neurotransmitter release was characterized in cultured hippocampal neurons obtained from wild‐type, heterozygous, and homozygous ΔE‐torsinA knock‐in mice using two approaches. In the first approach, patch‐clamp electrophysiology was used to record glutamate‐mediated miniature excitatory postsynaptic currents (mEPSCs) in the presence of the Na⁺ channel blocker tetrodotoxin (TTX) and absence of GABA_A receptor antagonists. The intervals between mEPSC events were significantly shorter in neurons obtained from the mutant mice than in those obtained from wild‐type mice. In the second approach, the miniature exocytosis of synaptic vesicles was detected by imaging the unstimulated release of FM dye from the nerve terminals in the presence of TTX. Cumulative FM dye release was higher in neurons obtained from the mutant mice than in those obtained from wild‐type mice. The number of glutamatergic nerve terminals was also assessed, and we found that this number was unchanged in heterozygous relative to wild‐type neurons, but slightly increased in homozygous neurons. Notably, in both heterozygous and homozygous neurons, the unitary synaptic charge during each mEPSC event was unchanged. Overall, our results suggest more frequent miniature glutamate release in neurons with ΔE‐torsinA mutations. This change may be one of the underlying mechanisms by which the excitability of the central nervous system is enhanced in the context of DYT1 dystonia. Moreover, qualitative differences between heterozygous and homozygous neurons with respect to certain synaptic properties indicate that the abnormalities observed in homozygotes may reflect more than a simple gene dosage effect. Synapse 66:807–822, 2012. © 2012 Wiley Periodicals, Inc.     

Efficacy of prolonged treatment following combination with ribavirin and interferon for chronic hepatitis type C: A pilot study.

The aim of the present study was to assess the efficacy of the prolonged interferon monotherapy following combination treatment. Seventy-six patients were enrolled. Of these, 7 were withdrawn while undergoing treatment with interferon combined with ribavirin, and 12 remained positive for HCV-RNA at the completion of the combination treatment. We studied 57 Japanese patients with chronic hepatitis C due to genotype 1b HCV of a high viral load. These patients tested negative for HCV-RNA at the completion of the combination treatment for 24 weeks. After the combination treatment, 29 patients of the prolonged treatment group successively received interferon-alpha monotherapy for 24 weeks, while 28 patients in the combination treatment alone group received no medication. The rate of a sustained virologic response (SVR) was higher in the prolonged treatment group (41%, 12/29) than in the combination treatment alone group (25%, 7/28), but not significantly. Patients who became HCV-RNA negative by 4 weeks after the start of the combination treatment showed an SVR rate of 86%. The prolonged treatment resulted in SVR in all five patients who newly became HCV-RNA negative at 12 weeks. In conclusion, the prolonged treatment was effective for patients who newly became HCV-RNA negative at 12 weeks.