Clinical significance of antibodies to nonstructural and core proteins of hepatitis C virus in posttransfusion hepatitis patients during long-term follow-up

The prevalence of hepatitis C antibodies (anti- HCV) among multitransfused patients was studied and compared with predicted values obtained from a post-transfusion hepatitis study and from data on the prevalence of anti-HCV among blood donors. The prevalence of hepatitis B core antibodies (anti-HBc) was also studied to determine the routes of transmission of hepatitis C virus. The patients consisted of 65 dialysis patients (57 on haemodialysis and 8 on continuous ambulatory peritoneal dialysis) and 71 leukemia patients in long-term remission [49 with acute myeloid leukemia (AML) and 22 with acute lymphatic leukemia (ALL)]. The presence of anti-HCV was investigated using a second generation enzyme-linked immunosorbent assay. Reactive samples were confirmed by a second generation recombinant immunoblot assay. Anti-HBc was studied in the 65 dialysis patients and in 40 of the leukemia patients. Three (4.6%) of the 65 dialysis patients and 12 (24.5%) of the 49 AML patients were anti-HCV positive whereas all of the ALL patients were seronegative. The total number of blood units transfused to 134 patients (data on two dialysis patients were not available) was 18,148, out of which 17,575 units had been transfused prior to the initiation of anti- HCV screening of blood donors. On the basis of the anti-HCV prevalence among blood donors and the incidence of post-transfusion hepatitis, the predicted number of seropositive patients was 11 and 18, respectively. Five of the 65 dialysis patients were anti-HBc positive, compared with only one of the 40 leukemia patients. It is concluded that the anti-HCV prevalence among dialysis and leukemia patients is concordant with the risk of receiving contaminated blood products, whereas hepatitis B infection may have other routes of transmission in dialysis patients. © 1993 Wiley-Liss, Inc.     

Protection of rabbits against HTLV-II infection with a synthetic peptide corresponding to HTLV-II neutralization region

Summary Rabbit immune sera raised against synthetic peptides of the HTLV-II envelope gp46 region were examined for HTLV-II neutralization ability by HTLV-vesicular stomatitis virus (VSV) pseudotype assay and syncytium inhibition assay. HTLV-II neutralization activity was detected in the sera against HTLV-II Env gp46, 80–103 but not in those to HTLV-II Env gp46, 171–196. Three rabbits immunized with the synthetic peptide of HTLV-II Env gp46, 80–103 and three non-immunized rabbits were challenged with intravenous inoculation of an HTLV-II-producing human cell line (MOT, 1×10⁷ cells). The non-immunized rabbits showed seroconversion for HTLV-II after 2 weeks and maintained persistent infection but the immunized rabbits were protected from HTLV-II infection. Nested or repeated polymerase chain reaction revealed the presence of HTLV-II provirus sequences in the non-immunized rabbits but not in the immunized rabbits. These results suggest that peptide vaccination with a synthetic peptide corresponding to the HTLV-II neutralization region is useful for preventing HTLV-II infection.     

Kinetic profiles of sequential gene expressions for chemokines in mice with contact hypersensitivity

Using cDNA microarray technology, the expression of chemokine genes in the elicitation site of 2,4,6-trinitrochlorobenzene-induced contact hypersensitivity (CHS) was examined in mice. Of the 33 genes analyzed, levels of 11 gene expressions changed, and these can be assigned to four groups based on their kinetic patterns; (1) LARC/CCL20 whose mRNA level increased rapidly at 3 h post-challenge and then gradually decreased, (2) JE/CCL2, MARC/CCL7, MIP-1gamma/CCL9, monocyte chemoattractant protein (MCP)-5/CCL12, ELC/CCL19 and BRAK/CXCL14 whose mRNA levels increased with time and reached the maximum at 6-9 h post-challenge, (3) LIX/CXCL5, Mig/CXCL9 and IP-10/CXCL10 whose mRNA levels increased gradually at least up to 12 h post challenge, and (4) SLC/CCL21 whose mRNA level decreased gradually with time after challenge. The findings suggest that sequential expression of chemokine genes is essential for orientating non-specific skin response to hapten-specific CHS response through the recruitment of inflammatory cells such as neutrophils, monocytes/macrophages and T-cells from the circulation into the tissue site.     

Evaluation of the theory of cardiac-output computation from transthoracic impedance plethysmogram

To analyse the limit of the stimation of stroke volume by thoracic impedance plethysmography (SV_z), we considered an elastic tube forced with a trapezoidal flow input as a model of the aorta, and, based on Kubicek's equation, the volume input (SV_a) was related to its impedance change via the model system parameters such as elasticity, fiuid inertia, peripheral resistance, total impedance across the tube and the rise and fall time of the input. SV_z is equal to SV_a only when the inflow is a square wave. The ratio SV_z/SV_a decreases with increasing input rise time, while it increases with increasing fall time, if the maximum flow rate and ejection time of the inflow are held constant. SV_z hardly changes in association with changes in elasticity, fluid inertia, peripheral resistance or total impedance. A part of the results, the relationship between SV_z, transthoracic total impedance and aortic flow waveform, was also demonstrated in dogs.     

Malignant fibrous histiocytoma of the pancreas

An extremely rare case of malignant fibrous histiocytoma In the pancreas Is reported. A 70-year-old man complained of upper abdominal discomfort. A tumor in the head of the pancreas was demonstrated by ultrasonography and computed tomography. The surgical specimen revealed a relatively well demarcated tumor, 9 × 7 × 6.5cm in size. Microscopically, fibroblastic, histiocytic, and muitinucleated giant tumor cells were observed in the myxoid area, but some tumor cells had proliferated in a storiform-pleomorphlc pattern. Immunohtstochemically, some tumor cells were positive for lysozyme, α-1-antitrypsin, α-1-antichymotrypsin, and vimentin. Electron microscopically, tumor cells showed a combination of fibroblastic and histiocytic features. The patient Is currently well with no evidence of recurrence or metastasis 22 months after operation.     

Cartilage regeneration using slow release of bone morphogenetic protein-2 from a gelatin sponge to treat experimental canine tracheomalacia: a preliminary report

We investigated whether saber sheath-type tracheomalacia could be treated by the slow release of bone morphogenetic protein (BMP)-2 from a gelatin sponge. A 1 cm gap was made in the middle portion of each of 10 consecutive tracheal cartilage rings in the canine cervix (control group, n = 3), then a gelatin sponge containing 12 microg of BMP-2 solution was implanted in the gap (12 microg group, n = 3). In another group (120 microg + P group, n = 3), the implanted gelatin sponge contained 120 microg of BMP-2 solution, and the gap was covered with periosteum. All of the control dogs developed saber sheath-type tracheomalacia, whereas tracheomalacia was not observed in the 12 microg and 120 microg + P groups. In the 12 microg group, fibrous cartilage was observed at the ends of the cartilage stumps. In the 120 microg + P group, newly formed bone and cartilage were observed to form a bridge between the cartilage stumps. The regeneration of cartilage or bone induced by the slow release of BMP-2 from a gelatin sponge might be useful for treatment of tracheomalacia.     

Polymorphisms and the differential antiviral activity of the chicken Mx gene

The nucleotide sequence of chicken Mx cDNA was reported earlier using the White Leghorn breed in Germany, but it showed no enhanced resistance to viruses. In this study, the nucleotide sequences of chicken Mx cDNA were determined in many breeds. A total of 25 nucleotide substitutions, of which 14 were deduced to cause amino acid exchanges, were detected, suggesting that the chicken Mx gene is very polymorphic. Transfected cell clones expressing chicken Mx mRNA were established after the Mx cDNA was constructed with an expression vector and introduced into mouse 3T3 cells, and the Mx genes from some breeds were demonstrated to confer positive antiviral responses to influenza virus and vesicular stomatitis virus. On the basis of the comparison among the antiviral activities associated with many Mx variations, a specific amino acid substitution at position 631 (Ser to Asn) was considered to determine the antivirally positive or negative Mx gene. Thus, a single amino acid substitution influences the antiviral activity of Mx in domesticated chickens.     

Open food challenge with milk, egg white and wheat

Background: A method for open food challenge test to determine food allergy has not been established in an evidence-based manner. Methods: We conducted an analysis of 438 open food challenges of raw milk (n=133, mean age 2.7+/-1.9 years), boiled egg white (n=216, 2.8+/-2.1 years) or udon noodles (n=89, 2.7+/-1.7 years) for the patients aged 1 year or more. Doses were increased (trace amounts, 1 g, 2 g, 5 g, 10 g, 20-30 g) every 20 minutes. Results: In total, 151 (38.5%) of food challenges were positive. The positive rates of milk, egg and wheat challenges were 35.8%, 42.4% and 33.3%, respectively. Of these, 76.2%, 32.5%, 27.8% and 0.7% had, respectively, skin, respiratory, gastrointestinal and cardiovascular symptoms. Although the prevalence of positive challenge increased with level of specific IgE, it did not correlate with the threshold amount of positive food challenge or the severity of symptoms. Among the challnege positive patients, 10.6% required injection of antihistamines, corticosteroids or adrenalines for the treatment of the symptoms. Conclusions: This challenge protocol seemed to be appropriate and safe.