[Adequate size of elephant trunk in the procedure of total arch replacement for acute aortic dissection].

Total aortic arch replacement using the 'elephant trunk (ET)' procedure has commonly been applied to acute aortic dissection, but enlargement of a residual false lumen of the descending thoracic aorta sometimes occurs. We performed endovascular stent-grafting to close the entry as the second operation and obtained successful outcomes. From April 1997 to January 2004, we performed the modified ET procedure for acute aortic dissection in 29 patients and evaluated postoperative changes of the false lumen. In many cases of the residual false lumen, kinks and wrinkles were observed at the site of the ET grafts in the descending aorta. An adequate length of ET would be about 8 cm long to prevent kinking, and a diameter about 20 mm to prevent wrinkles.

Association of HLA-DR with sarcoidosis. Correlation with clinical course.

HLA-DR typing was performed in 58 Japanese patients with sarcoidosis. We found a significantly increased frequency of HLA-DRw52 (p less than 0.0007; pc less than 0.009) and DR5J (p less than 0.004; pc less than 0.05). (Corrected probability value is given as pc.) In 34 of 58 patients the disease resolved spontaneously. There was no significant difference between the frequency of DRw52 and the resolution rate of disease. The frequency of DR5J was increased significantly in the unresolved cases. Our results also suggest that DRw52 is concerned with onset of sarcoidosis and DR5J antigen has an effect on the clinical course of this disease.

Peripheral primitive neuroectodermal tumor involving the paravertebral and retroperitoneal regions.

A rare case of peripheral primitive neuroectodermal tumor (PNET) is reported. A 68-year-old woman complaining of lumbago was admitted to our hospital. Diagnosis was made based on pathological findings characterized by Homer Wright-type rosettes. Ultrastructural examination showed the presence of neurosecretory granules and short cytoplasmic processes, which were highly suggestive of neural differentiation. Chromosomal analysis of the neoplastic cells revealed translocation (11;22)(q24;q12), which is often found in Ewing's sarcoma and Askin tumor. These results strengthen the hypothesis of a common histogenesis for these small round cell tumors, and suggest common oncogenesis for these neoplasms.

Evaluation of phagocytic function of canine peripheral polymorphonuclear leucocytes by whole blood chemiluminescence.

Zymosan-induced and luminol-aided chemiluminescence (CL) of whole blood from beagle dogs was estimated for the function of polymorphonuclear leucocytes (PMNs). Whole blood (0.1 ml) was examined directly and results were obtained within 20 min. A phagocytic function of PMNs can be estimated from the peak CL counts and the number of PMNs in a specimen, and the opsonic activity can also be estimated by the peak time showing peak CL after the addition of non-opsonized zymosan. The optimal temperatures to keep diluted whole blood for the CL measurement was around 13 degrees C. Thus, this method offers information concerning the functions of phagocytic cells in whole blood.

Changes in anti-erythrocyte membrane antibody level of dogs experimentally infected with Babesia gibsoni.

To account for the conflict between the excessive destruction of erythrocytes and the number of parasitized erythrocytes in dogs infected with Babesia gibsoni, we examined the correlation between anti-erythrocyte membrane antibody level (AEMAL) and the number of erythrocytes (RBC count) in dogs with experimentally induced babesiosis using hematological examination and an enzyme linked immunosorbent assay (ELISA). In the infected dogs without splenectomy, more prominent reduction in RBC count accompanied with the elevated AEMAL was presented than anticipated from parasitemia until the 21st day. Furthermore, autoagglutinated erythrocytes and spherocytes were demonstrated in blood films. These results suggest that a humoral immunologic mechanism may be involved in a decrease in RBC count in dogs infected with B. gibsoni.

Protective immunity against multiple challenges of Brugia pahangi in Mongolian gerbils induced by drug-abbreviated infection.

Protective immunity against multiple challenge infections was examined in Mongolian gerbils after a drug-abbreviated infection with Brugia pahangi. The gerbils treated with mebendazole (MBZ) during the late prepatent period (7-9 weeks of postinfection) were challenged with 5 inoculations of 50 infective larvae of B. pahangi at 4-week intervals. The worm burden was significantly reduced 68.6% (19.0 in average number) to that of controls (60.6) and was accompanied with enhanced eosinophil responses 1 week after each challenge. MBZ-treated gerbils suppressed microfilaremia almost completely after the challenge infections.

Detection of babesia species from infected dog blood by polymerase chain reaction.

Polymerase chain reaction (PCR) was first applied to diagnosis of canine babesiosis in Japan. Blood samples from 13 dogs suffering from canine babesiosis were used for examination of specificity and sensitivity of the PCR diagnosis. Of the 13 dogs, three were experimentally infected, and ten were naturally infected with Babesia species in west part of Japan. We designed a nested PCR to amplify the babesial small subunit ribosomal RNA gene and found that only the nested PCR produced a visual band, which were not apparent by the first-round PCR to the positive samples. Specificity of the nested PCR was confirmed by amplification after the second-round PCR. Sensitivity of the nested PCR was examined by diluting the blood samples from infected and uninfected dogs. The nested PCR was found to show positive results on the most diluted blood at 0.0001% parasitemia. These results indicate that the nested PCR is highly sensitive and useful for diagnosis of canine babesiosis.

Comparison of partial ribosomal DNA sequences of Babesia gibsoni occurring in Miyazaki prefecture, Japan.

Nucleotide sequences of ribosomal DNA (rDNA) of Babesia (B.) gibsoni occurring in Miyazaki, western Japan, were examined using blood samples obtained from seven dogs suffering from natural canine babesiosis. DNA isolated from these blood samples was subjected to the polymerase chain reaction (PCR). The nucleotide sequences of the PCR products were determined and compared with other rDNA sequences of B. gibsoni isolated from Asia, Europe and U.S.A. Although homology values between our isolates and those isolated from Europe and U.S.A. were both 84.0%, respectively, our isolates were identical to the Asian types. In conclusion, B. gibsoni occurring in Miyazaki was revealed to have the genotype Asia 1 or Asia 2 from a comparison of the partial rDNA sequences.

Immunosuppression in dogs naturally infected with Babesia gibsoni.

We examined lymphoproliferative response to phytohemagglutinin and anti-parasite antibody level in dogs naturally infected with Babesia gibsoni. The dogs with subclinical B. gibsoni infection exhibited suppressed lymphocyte blastogenesis. Prominent depression of lymphocyte blastogenesis and anti-parasite antibody production was observed in dogs suffering from relapses of clinical B. gibsoni infection.

Failure of killed Corynebacterium parvum in induction of protection in C57BL/6 mice against Babesia rodhaini challenge infection.

We examined the survival rate of C57BL/6 mice challenged with Babesia rodhaini 21 days post-killed Corynebacterium parvum (KCP) inoculation in comparison with ICR mice. All KCP-inoculated ICR mice survived the challenge infection, while all KCP-inoculated C57BL/6 mice died. To account in part for the difference in protective effects of KCP, stimulatory effects of KCP on splenic phagocyte chemiluminescence (CL) response were investigated in C57BL/6 and ICR mice. The KCP-inoculated ICR mice exhibited significantly higher CL values than ICR mice without KCP inoculation. No significant difference in CL value was observed between C57BL/6 mice with and without KCP inoculation. These results taken together, the lack of resistance of the KCP-inoculated C57BL/6 mice to B. rodhaini infection may be attributed in part to small stimulatory effect of KCP on splenic phagocytes.

Suppressed antibody response to sheep erythrocytes in experimentally Babesia rodhaini-infected mice.

Mice experimentally infected with Babesia rodhaini were immunized with sheep red blood cells (SRBC), and the splenic plaque forming cell (PFC) response to SRBC was investigated. Suppressed splenic antibody response to SRBC accompanied with the elevated parasitemia was recognized. This evidence suggests that an immunosuppression in B. rodhaini infection may be involved in the multiplication of parasites contributing to high mortality of mice infected with B. rodhaini.

Effect of clindamycin therapy on phagocytic and oxidative activity profiles of spleen mononuclear cells in Babesia rodhaini-infected mice.

Spleen weight, the number of spleen mononuclear cells, and their phagocytic activity in groups of Babesia rodhaini-infected mice treated with diminazene diaceturate and clindamycin increased significantly in the early stage of treatment, and then decreased in the final stage of treatment to approximately the pre-infection level. The number of F4/80-positive macrophages and their oxidative activity per mean whole-spleen weight also increased significantly during the course of treatment in comparison with the untreated group. The increases in the clindamycin-treated group were more prominent than those in the group treated with diminazene diaceturate, suggesting the effectiveness of clindamycin therapy for murine babesiosis.

Isolation of Babesia gibsoni piroplasms from infected erythrocytes of dogs.

To eliminate the influence of anti-dog erythrocyte membrane antibodies in Babesia gibsoni-infected dogs on the immunological investigations of parasites, an attempt was made to purify B. gibsoni piroplasms from infected erythrocytes by N2 cavitation and centrifugation in a Percoll discontinuous density gradient. Although electron microscopic examination revealed that the concentrated piroplasms visible as a band at the interface between 30% and 40% Percoll solutions were contaminated with a small amount of erythrocyte membrane debris, little contamination was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western immunoblots. Hence, the isolated parasites may be usable for immunological examinations of parasites.

Quantitation of erythrocyte-bound IgG by competitive solid-phase enzyme immunoassay.

A competitive solid-phase enzyme immunoassay technique for the quantitation of erythrocyte (RBC)-bound IgG was devised. This method is highly sensitive, reproducible and can be performed more simply. Anemic dogs with a positive Coombs' test result were observed to have higher RBC-bound IgG values (IgG concentration, ng/ml) than healthy dogs.

Therapeutic effect of clindamycin and tetracycline on Babesia rodhaini infection in mouse model.

In order to identify the alternative effective chemotherapeutic agents for murine babesiosis, some selected drugs were examined for their efficacy against protozoan infection in the mouse-Babesia rodhaini (B. rodhaini) model. Clindamycin was not completely effective for elimination of parasites in a dose of 50 mg or 100 mg/kg BW/day b.i.d. but effective to prolong the life span of hosts, while it completely cured B. rodhaini infections in a dose of 200 mg. On the other hand, a double therapy consisting of 2 treatments with 100 mg clindamycin and 100 mg clindamycin and with 100 mg clindamycin and 100 mg tetracycline; respectively, and a single therapy with 100 mg tetracycline or 200 mg clindamycin, had a possibility to clear away B. rodhaini organisms from hosts. However, almost all the treatment groups, had a relapse of the infection within 10 days post treatment or re-treatment. Cured mice by treatment with clindamycin and clindamycin, or clindamycin and tetracycline showed complete resistance against challenge with B. rodhaini, while mice cured by administration of clindamycin at 200 mg or tetracycline at 100 mg showed incomplete resistance to challenge infection. The present data suggest that the two former chemotherapies can induce effective protective immunity (premunization), but the latter two chemotherapies induce incomplete premunization.

Secondary antibody response to Haemophilus somnus antigen in breeding Japanese black cattle fed selenium-deficient and alpha-tocopherol-fortified diets.

The cattle with adequate alpha-tocopherol (Vit E) and marginally deficient selenium (Se) status manifested significantly lower anti-Haemophilus somnus antibody titer than the cattle supplemented with Se in the later stage of an 8-week trial. However, in the early stage no difference was observed in magnitude of anti-H. somnus antibody development between them. These results suggested that Se may contribute to anti-H. somnus antibody production, and that Vit E can make up for Se deficiency to a certain degree.

Anthelmintic efficacy of milbemycin oxime against Trichuris vulpis in dogs.

The anthelmintic efficacy of milbemycin oxime against dog whipworm, Trichuris vulpis, was evaluated. A total of 21 T. vulpis positive dogs were divided into 3 groups, one (5 dogs) for control and the other two (8 dogs each) for anthelmintic treatment with oral administration of milbemycin oxime.

Immunologic characteristics of anti-erythrocyte membrane antibody produced in dogs during Babesia gibsoni infection.

Serum anti-erythrocyte membrane (RBCm) antibodies and anti-RBCm antibodies eluted from erythrocytes of Babesia gibsoni-infected dogs were examined for immunologic characteristics by immunoblotting analysis. Serum anti-RBCm antibodies of the dogs before and after the experimental inoculation with parasitized erythrocytes reacted with cytoskeletal (bands 1, 2, 2.1, 4.1, 4.2 and 5) and transmembrane structural (band 3) proteins of either self or non-self RBCm. Anti-RBCm antibodies eluted from erythrocytes of B. gibsoni-infected dogs reacted with bands 3 and 4.2 of self and non-self RBCm.

Anti-erythrocyte membrane antibodies detected in sera of dogs naturally infected with Babesia gibsoni.

Due to the potential for anti-erythrocyte membrane antibodies as possible enhancers of erythrocyte destruction, the presence of serum anti-erythrocyte membrane antibodies in 31 dogs with Babesia gibsoni infection admitted to a veterinary hospital was investigated by an enzyme linked immunosorbent assay (ELISA) and immunoblotting analyses. This infection resulted in an increase of anti-erythrocyte membrane antibodies in 84% (IgG) and 74% (IgM) of 31 infected dogs, respectively. This was confirmed by the similarity in the protein profiles of the erythrocyte membrane antigens immunoblotted with rabbit antiserum to dog erythrocyte membrane antigens and infected dog serum. These results suggest the production of anti-erythrocyte membrane antibodies was induced by B. gibsoni infection.

Sensitive enzyme-linked immunosorbent assay (ELISA) to measure parasite-specific antibodies of Indian soft-furred rats, Millardia meltada.

Immunoglobulin G (IgG) of Indian soft-furred rat, Millardia meltada, was purified by an immunoaffinity chromatography and antibodies against it was raised in rabbit. Using this rabbit anti-M. meltada IgG antibody, sensitivity of enzyme-linked immunosorbent assay (ELISA) to measure parasite-specific antibodies in the sera of M. meltada was markedly enhanced than the previous method using rabbit anti-mouse IgG and rabbit anti-rat IgG antibodies, which could cross-react to M. meltada IgG. Since M. meltada could effectively produce circulating antibodies against two intestinal helminths, Strongyloides venezuelensis and Nippostrongylus brasiliensis, the high susceptibility of this animal to an array of parasites seems to be not due to general immunological deficiency.