Morphology of hepatitis C and hepatitis B virus particles as detected by immunogold electron microscopy

We performed indirect immunogold electron microscopy (EM) for immunological identification and characterization of hepatitis C virus (HCV). To clarify the morphology of HCV, an indirect immunogold EM of two plasma samples from patients with high HCV RNA titers was carried out using antibodies specific for the putative HCV envelope protein (E) 1. Spherical virus particles 55–65 nm in diameter with delicate spike projections were detected in the 1.14–1.16 g/ml fractions after sucrose density gradient centrifugation. Polyclonal and monoclonal antibodies to the putative HCV E1 specifically recognized these particles. In addition, immunogold EM of the samples was also performed to uncover the morphology of HCV core particles. Spherical particles 33–40 nm in diameter (average, 37 nm) were detected in the 1.22- to 1.25-g/ml fractions by conventional EM after sucrose density gradient centrifugation. Immunogold EM using rabbit polyclonal antibody (RR8) specific for the putative HCV core protein and colloidal gold-labeled goat antirabbit IgG showed binding of the gold particles with RR8. Some of the HCV core particles showed icosahedric morphology. Optical rotation technique showed that the HCV core particles exhibit sixfold symmetry and that the length of the regular hexagon side is approximately 20 nm, suggesting that they have an icosahedric structure. Further, the detection limit of the indirect immunogold EM was evaluated in 11 plasma samples from chronic hepatitis B patients with different degrees of hepatitis B virus (HBV) DNA titers using antihepatitis B surface antigen antibody. The study showed that the detection limit of virus using this method is 10⁷ virions/ml.     

Morphological identification of hepatitis C virus E1 and E2 envelope glycoproteins on the virion surface using immunogold electron microscopy

It is known that hepatitis C virus (HCV) particles are spherical, 55-65 nm particles with fine surface projections of about 6 nm in length and with a 30-35 nm inner core. We have reported that free HCV particles labeled with gold particles specific to the HCV E1 glycoprotein are located in 1.14-1.16 g/ml fractions from plasma samples with high HCV RNA titers after sucrose density gradient centrifugation. However, the morphology of the HCV E2 glycoprotein on the virion has not yet been elucidated. To visualize HCV E2 localization on the virion, we used the same plasma samples where HCV particles were clearly shown. An indirect immunogold electron microscopic study was carried out using monoclonal and polyclonal anti-HCV E2 antibodies. HCV-like particles specifically reacted with the anti-HCV E2 antibodies. Moreover, to evaluate the localization of the HCV E1 and E2 glycoproteins on the virion surface, an immunogold electron microscopic study using double labeling with anti-HCV E1 antibodies and anti-HCV E2 antibodies was also performed. These particles also specifically reacted with both anti-E1 and E2 antibodies. This is the first report showing the presence of both HCV E1 and E2 glycoproteins on HCV virion surface in human plasma samples.     

Semiquantitative analysis of C-11 methionine PET may distinguish brain tumor recurrence from radiation necrosis even in small lesions

Objective

¹¹C-Methionine positron emission tomography (MET-PET) has been used to distinguish brain tumor recurrence from radiation necrosis. Because the spatial resolution of conventional PET scanners is low, partial volume effect (PVE) may decrease the detectability of small tumor recurrence. The aim of this study is to investigate the diagnostic value of MET-PET upon semiquantitative analyses in particular PVE-affected small lesions.

Methods

First, we performed a phantom experiment to investigate what size lesion is affected by PVE. This study included 29 patients (33 lesions) suspected of recurrent brain tumors by magnetic resonance imaging (MRI) after radiation therapy. All of them received MET-PET. Semiquantitative analysis was performed using maximum standardized uptake value (SUVmax) and lesion-versus-normal ratio (L/N ratio). ROC analysis was also assessed about the diagnostic value of MET-PET.

Results

From the result of the phantom experiment, lesions smaller than 20 mm in brain mode or smaller than 30 mm in whole-body mode were defined as PVE-affected lesions. Histological analysis or clinical follow-up confirmed the diagnosis of tumor recurrence in 22 lesions, and radiation necrosis in 11 lesions. L/N ratios of recurrence and necrosis for overall lesions were 1.98 ± 0.62 and 1.27 ± 0.28, respectively (p < 0.01). In the PVE-affected lesions, L/N ratio for recurrence (1.72 ± 0.44) was also significantly higher than that for necrosis (1.20 ± 0.11) (p < 0.01). On the ROC analysis for the PVE-affected lesions, the area under the curve for L/N ratio (0.897) was significantly higher than that for SUVmax (0.718) (p < 0.05). These areas under the curve were almost equal to that of overall lesions for L/N ratio (0.886) and for SUVmax (0.738).

Conclusions

Semiquantitative analysis of MET provided high diagnostic value even for PVE-affected small lesions. MET-PET enables early diagnosis of recurrence of brain tumor in the follow-up after the radiation therapy.     

Radiological anatomy of spontaneous splenorenal shunts in patients with chronic liver disease

Purpose

We evaluated anatomical variations of spontaneous splenorenal shunt (SSRS) and the prevalence of portosystemic shunts in patients with chronic liver disease by CT.

Materials and methods

A total of 451 patients with chronic liver disease underwent contrast-enhanced computed tomography between October 2010 and April 2011. The prevalence of portosystemic shunts including SSRS and gastrorenal shunt, and the frequency of hepatic encephalopathy were examined. The course of the shunt and the point of confluence with the renal vein of the SSRS were analyzed.

Results

SSRSs or gastrorenal shunts were found in 11.1 and 5.0% of the patients, respectively. Anatomical variations were classified into three types according to the point of confluence as follows: type 1 = the SSRS joined the inferior phrenic vein (n = 33), type 2 = the SSRS joined the gonadal vein (n = 7), and type 3 = the SSRS joined the left renal vein (n = 14). The course of the SSRS from the splenic hilum was classified as medial (n = 46), posterior (n = 2), or anterolateral (n = 2).

Conclusions

SSRSs were classified into three types depending on the confluence point with the renal vein, and into three types of course. These findings are useful for preoperative information.

     

Formation of N7-methylguanine in nuclear DNA and cytoplasmic RNA in mice on continuous oral administration of dimethylnitrosamine-3H solution

Summary Radioactivity in liver nucleic acids increased to a plateau in one week, and decreased slightly after 3 weeks. Radioactivity of nucleic acids in the lungs and kidneys was less than that of liver nucleic acids for the first week, but then gradually increased to the same level as the latter. However, the amount of N⁷-methylguanine in nucleic acids was 2 to 4 times more in the liver than in the kidneys and lungs after 30 days. The maximal level of N⁷-methylguanine in DNA was found after 21 days, when approximately 0.1% of guanine residues in liver DNA were methylated. Maximum methylation of RNA was also observed after 21 days. Initially methylation of liver 4S RNA was more than that of ribosomal RNA, but later the extents of methylation to the cytoplasmic RNA species became similar.

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Die Bildung von N⁷-Methylguanin in der Kern-DNS und cytoplasmatischen RNS bei Mäusen während kontinuierlicher oraler Gabe einer Lösung von Dimethyl-nitrosamin-³H

Zusammenfassung Die Aktivität der Nucleinsäuren stieg in der Leber in einer Woche zu einem Plateau an und nahm nach 3 Wochen wieder leicht ab, in Lungen und Nieren war sie in der ersten Woche geringer als in der Leber, stieg aber später zur selben Höhe wie in der Leber. Die Menge von N⁷-Methylguanin in den Nucleinsäuren war jedoch nach 30 Tagen in der Leber 2-bis 4mal größer als in Nieren und Lunge. Der höchste Spiegel von N⁷-Methylguanin in DNS fand sich nach 21 Tagen, wenn etwa 0.1% der Guaninreste in der Leber DNS methyliert waren. Maximale Methylierung der RNS wurde ebenfalls nach 21 Tagen beobachtet. Die anfängliche Methylierung von 4S RNA¹ war größer als die der ribosomalen RNS; später wurde das Ausmaß der Methylierung ähnlich dem der cytoplasmatischen RNS.

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The Abbreviations used are DMN dimethylnitrosamine - EDTA ethylenediaminetetraacetic acid disodium - SSC 0.15 M NaCl-0.015 M sodium citrate This work was partly supported by a grant from the Ministry of Education of Japan.     

Predictive value of Tc-99m galactosyl human serum albumin liver SPECT on the assessment of functional recovery after partial hepatectomy: a comparison with CT volumetry

Objective

Predicting liver functional reserve is important before partial hepatectomy. However, it is difficult to predict using morphologic imaging modalities, such as CT and MRI. In this study, we assess the usefulness of galactosyl human serum albumin (GSA) scintigraphy in predicting liver function recovery.

Methods

We performed ^99mTc-GSA scintigraphy before operation in 56 patients. Each patient was administered 185 MBq of ^99mTc-GSA by intravenous injection. Serial images were taken immediately after the administration for 40 min. SPECT images were obtained to make a functional map. We calculated the functioning parameter residual GSA-Rmax (GSA-RL) using analysis software developed by Dr. N. Shuke. In addition, we compared GSA-RL with the morphological parameter residual liver volume (RLV-CT) calculated by conventional CT and serum albumin (Alb) or cholinesterase (ChE). We analyzed the correlation between imaging parameters and the postoperative recovery periods of serum albumin (r-Alb) and cholinesterase (r-ChE) and the values at 1 and 3 months for serum albumin (1M-Alb, 3M-Alb) and cholinesterase (1M-ChE, 3M-ChE).

Results

We found significant correlations between GSA-RL and r-Alb, r-ChE, 1M-Alb, 3M-Alb, 1M-ChE and 3M-ChE, but not between RLV-CT and the same parameters.

Conclusion

The GSA-RL calculated by ^99mTc GSA-SPECT was a useful parameter for predicting postoperative liver function recovery that should be implemented before partial hepatectomy.     

Comparison of18F-fluoromethylcholine and 2-deoxy-D-glucose in the distribution of tumor and inflammation

PURPOSE: The distribution characteristics of 18F-fluoromethylcholine (18F-choline) in tumor and inflammatory tissue were compared with those of 14C or 3H-2-deoxyglucose (2DG) as a substitute for fluorodeoxyglucose (FDG). METHODS: A solid tumor model of AH 109A in the back of Donryu rats and an aseptic inflammation model of turpentine oil injection subcutaneously in rats were used for experiments. Tissue distribution was examined at 5, 30 and 60 min after injection of a mixture of 18F-choline and 3H-2DG. Double-tracer high-resolution autoradiographs (ARGs) of tumor and inflammation were obtained using 18F-choline and 14C-2DG. Whole body (WB) ARG was performed with 18F-choline. RESULTS: Tumor uptake of 18F-choline reached a peak at 30 min, when the tumor to blood ratio was 5.1. Both tumor and inflammation uptake of 2DG were higher than those of 18F-choline. 18F-choline uptake by inflammation was lower than that by tumor. The tumor to brain uptake ratio was 5.7 with 18F-choline and 1.2 with 2DG. In the ARG of inflammation, linear or ring-like structures of 2DG uptake were observed in the wall of the abscess, but were not identified with 18F-choline. Photomicrography showed that the uptake was limited to granulocytes, macrophages and fibroblasts, consistent with sub-acute or chronic inflammation. CONCLUSION: 18F-choline uptake by inflammation was lower than that of 2DG in the tissue distribution study, and 18F-choline uptake by abscess wall was significantly lower than that of 2DG in the autoradiography study. Our results may suggest the feasibility of 18F-choline-PET imaging for the differential diagnosis of cancer and chronic inflammation in lung and brain.     

Interventional radiologic treatment for idiopathic portal hypertension

Purpose: To evaluate the usefulness of interventional radiological treatment for idiopathic portal hypertension. Methods: Between 1995 and 1998, we performed an interventional radiological treatment in five patients with idiopathic portal hypertension, four of whom had refused surgery and one of whom had undergone surgery. Three patients with gastroesophageal varices (GEV) were treated by partial splenic embolization (PSE), one patient with esophageal varices (EV) and massive ascites by transjugular intrahepatic portosytemic shunt (TIPS) and PSE, and one patient with GEV by percutaneous transhepatic obliteration (PTO). Midterm results were analyzed in terms of the effect on esophageal and/or gastric varices. Results: In one woman with severe GEV who underwent three sessions of PSE, there was endoscopic confirmation that the GEV had disappeared. In one man his EV shrunk markedly after two sessions of PSE. In two patients slight reduction of the EV was obtained with one application of PSE combined with endoscopic variceal ligation therapy. PTO for GV in one patient resulted in good control of the varices. All patients have survived for 16–42 months since the first interventional treatment, and varices are well controlled. Conclusion: Interventional radiological treatment is effective for patients with idiopathic portal hypertension, whether or not they have undergone surgery.     

Acromesomelic Dysplasia in a Father and Son: Autosomal Dominant Inheritance

A father and son with typical acromesomelic dysplasia are reported, with the father more severely affected than the son. The disease was thus apparently transmitted in an autosomal dominant fashion. This is at variance with the autosomal recessive mode of inheritance assumed from hitherto reported families.     

Incidence and Etiology of Mental Retardation in Patients with Congenital Heart Disease

Of 1,235 patients (609 male; 626 female) with congenital heart disease for whom types, etiology and associated congenital anomalies were determinable, 129 patients (10.4%) had mental retardatin. Patients with congenital heart disease complicated by mental retardation included 70 (54.3%) with chromosome aberrations, three(2.3%) with single gene disorders, two (1.6%) caused by environmental insult, and two (1.6%) with other recognized syndromes. Among the remaining 52 patients, asphyxia at birt was noted in 16, including 12 complicated by multiple malformations, and 4 in whom mental retardedation was presumed to be due to the asphyxia. In the remaining 36 patients, the incidence of the complication of mental retardation in cyanotic congenital heart disese was significantly higher than that in acyanotic congenital heart disease was signicantly higher than that in acyanotic congenital heart disease. Patients with congenital heart disease of unknown etiology associated with mental retardation included those from two families considered to have new pedigree syndromes.