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Deposition conditions of cuprous oxide (Cu2O) thin films on glass substrates and nitrogen doping into Cu2O were studied by using reactive radio-frequency magnetron sputtering method. The effects of defect passivation by crown-ether cyanide treatment, which simply involves immersion in KCN solutions containing 18-crown-6 followed by rinse, were also studied. By the crown-ether cyanide treatment, the luminescence intensity due to the near-band-edge emission of Cu2O at around 680 nm was enhanced, and the hole density was increased from 1016 to 1017 cm−3. Finally, polycrystalline p-Cu2O/n-ZnO heterojunctions were grown for use in solar cells. Two deposition sequences were studied, ZnO deposited on Cu2O and Cu2O deposited on ZnO. It was found that the crystallographic orientation and current–voltage characteristics of the heterojunction were significantly influenced by the deposition sequence, both being far superior for the heterojunction with structure Cu2O on ZnO than for the inverse structure. We successfully obtained a photoresponse for the first time in the deposited thin film of Cu2O/ZnO.

SUMMARY After a primary infection by subcutaneous inoculation with the infective larvae (L3) of Nippostrongylus brasiliensis, the intestinal worm burden was higher and expulsion was slower in W/Wv mice than in +/+ mice. When the course of infection was segregated into the migratory and intestinal phases, protection during the migratory phase examined by the larval recovery from the lungs and that during the intestinal phase measured by worm burden after intraduodenal implantation with adult worms were both defective in W/Wv mice. The higher susceptibility of W/Wv mice during the migratory phase was normalized by bone marrow re constitution. On the other hand, higher susceptibility of W/Wv mice during the intestinal phase, which was measured by worm burden 24 h after intraduodenal implantation of the larvae recovered from the lungs of rats, was not normalized by bone marrow grafting. Furthermore, slower expulsion seen in W/Wv mice after intraduodenal implantation with adult worms was not hastened by bone marrow reconstitution. These results indicate that the protective mechanisms against N. brasiliensis operating during the migratory phase and those during the intestinal phase were different in terms of bone marrow dependency and that nonmyeloid cells utilizing c-kit ligand/receptor system to express their functions are involved in the rnucosal defence against N. brasiliensis.

Excretory and secretory (ES) products collected from adult worms of Strongyloides ratti stimulated interleukin-3 (IL-3) production with mesenteric lymph node cells from infected C57BL/6 mice, hut not with normal mesenteric lymph node cells. The IL-3 stimulating components were not major IgG binding antigens. Activity of the IL-3 stimulating components was stable by treatment with protease, although reduced by heating in boiling water.

We have been developing the externally-coupled transcutaneous energy transmission system (ECTETS) for a totally-implantable artificial heart (TIAH). The transcutaneous energy transmission (TET) system enables the TIAH to supply the driving energy without infectious disease and reduction of patient’s QOL (quality of life). Since the TET system uses the electromagnetic induction between the external (primary) and the internal (secondary) coils, it is necessary for the TET system to be compatible electromagnetically. In the practical use of artificial heart, such as a patient going out, the artificial heart is driven by the energy from the portable rechargeable battery outside of the body. In this paper, the drive performance and the electromagnetic compatibility of the TET system were investigated in case of using the external rechargeable battery. As a result, the ECTETS, driven by the external rechargeable battery consisting of the Lithium ion battery pack with a weight of 430 g, was able to drive the TIAH actuator for 4 hours and 9 minutes. The radiated emission from the ECTETS was suppressed within the regulation of class-B and group-1 in CISPR (international special committee on radio interference) Pub.11, and the ECTETS satisfied the electrostatic discharge immunity test based on IEC61000-4-2 (International Electrotechnical Commission), the radiation immunity test based on IEC61000-4-3, and the power supply frequency magnetic field immunity test based on IEC61000-4-8. Therefore, it was concluded that the ECTETS investigated had satisfactory characteristics in the drive performance and the electromagnetic compatibility.

Epidemiological data on food-borne parasitic zoonoses in Japan is obscure because of the lack of legislated registration system for the incidence of such diseases. Attempts were made to draw rough estimates of the current status of food-borne parasitic diseases in Japan by gathering the annual incidence of each disease by literal survey and personal communications. In addition, parasitic diseases referred to and diagnosed in the Department of Parasitology, Miyazaki Medical College during 1999 were analyzed for the causative agents and the route of infection.

Clinical features of a total of 30 paragonimiasis westermani patients referred to and diagnosed in our laboratory in 1999 were analyzed retrospectively. Most patients were middle-aged (average: 48 years, range: 13-72 years) with the male/female ratio of 19/11. Over 70% of the patients had respiratory symptom and over 80% had peripheral blood eosinophilia and high serum IgE level. All but two cases had radiologic abnormalities on the chest X-ray. Only in 3 cases were Paragonimus eggs detected in the sputum smear. We classified the patients into two groups depending on the chest X-ray findings: patients having pleurisy alone and those having nodular/cavitating lesions in the lung parenchyma. We measured parasite specific IgM/IgG antibodies in all patients sera by microplate ELISA. The mean parasite-specific IgM/IgG antibody ratio was significantly higher in the parenchymatous lesion group than in the pleurisy group. While IgM antibody titer had a strong positive correlation with the degree of eosinophilia in peripheral blood, IgG antibody titer had an inverse correlation. Although the degree of eosinophilia in peripheral blood was higher in the pleurisy group than in the parenchymatous lesion group, total IgE level in serum was comparable between the two groups. The present results indicate that pleurisy with eosinophilia and dominant IgM antibody are the characteristic features of the early stage of paragonimiasis, whereas parenchymatous lesions in lungs with low grade eosinophilia and dominant IgG antibody are of the late stage. These results suggest that detection of IgM antibody should always be considered for the immunodiagnosis for paragonimiasis-suspected patients with pleurisy.

A 27-year-old woman was admitted because of pain radiating through her back on neck flexion that had begun a month ago. She frequently ate raw beef liver. General physical examination revealed no abnormal findings, but she showed Lhermitte's sign neurologically. Fecal examination revealed no worm eggs. Blood cell counts showed mild eosinophilia (8.2%). The IgE level was mildly increased to 397 IU/ml (normal250). Cerebrospinal fluid examination showed 7 cells/microliter with 50% eosinophils. A test for anti-Ascaris suum IgG antibody was strongly positive in serum as well as in cerebrospinal fluid. Cervical MRI showed high-intensity areas in the spinal cord extending from the lower medulla to the C4 spine level on the T2-weighted images, and part of the lesion at the C3 spine level was enhanced by gadolinium. Treatment with albendazole 500 mg/day for six weeks ameliorated the Lhermitte's sign and MRI lesions, and reduced the anti-Ascaris suum antibody titers in the serum and cerebrospinal fluid. Larva migrans of Ascaris suum involving the central nervous system is considered to be extremely rare, but such cases showing mild neurologic impairment without systemic symptoms may have been overlooked.

The susceptibility of 129/SvJ mice to infection with Strongyloides venezuelensis was compared with that of C57BL/6 mice. After a primary infection, daily egg output in faeces (EPG) from 129/SvJ mice was lower and terminated earlier than that from C57BL/6 mice. Adult worm recovery from the small intestine of 129/SvJ mice on day 7 was also lower than that of C57BL/6 mice. When the numbers of larvae recovered from the lungs were examined on days 2, 3 and 4 after a primary infection, they were comparable between the two strains. On the other hand, when an equal number of larvae recovered from the lungs of each strain on day 3 were implanted orally into homologous strain mice, the magnitude of EPG and the number of adult worms in the small intestine on day 5 after implantation were significantly lower in 129/SvJ than in C57BL/6 mice. The number of mucosal mast cells in the jejunum was not significantly different between 129/SvJ and C57BL/6 naive mice. Total chondroitin sulphate concentration in the gut washings obtained from naive mice was significantly higher in 129/SvJ (11.34 +/- 9.48) than in C57BL/6 mice (1.09 +/- 0.77, P0.05). These results indicate that the natural resistance of 129SvJ mice to S. venezuelensis infection is expressed at the intestine, probably due to higher concentration of chondroitin sulphate, which prevents establishment of S. venezuelensis.

We investigated the graft-versus-myeloma effect (GVM) after allogeneic bone marrow transplantation (allo-BMT). Three patients with refractory multiple myeloma (MM) underwent related allo-BMT. Two of the patients showed disappearance of serum M protein 4 and 5 months after transplantation, respectively. One of them has remained in complete remission for more than 22 months after allo-BMT, with accompanying chronic GVHD. Two patients with relapse and disease progression after allo-BMT underwent donor lymphocyte infusion (DLI). Although one patient did not respond to DLI, the other developed acute GVHD after 4 weeks and achieved a 75% reduction in serum M protein. DLI did not produce severe acute GVHD or myelosuppression. These findings suggest the presence of a GVM effect. DLI may be an effective therapy for patients with MM who have relapsed after allo-BMT. Furthermore, non-myeloablative stem cell transplantation (mini-transplantation) for refractory MM should be investigated further as a potentially curative option.

Although it has been well established that the microchimerism occurs in the peripheral blood of the recipients after various settings in both clinical and experimental organ transplantation, nevertheless, their roles in inducing and maintaining acquired transplantation tolerance are controversial. Furthermore, regarding the cell lineages, kinetics, and functions of the cells that constitute the microchimerism after organ transplantation, solid information is not available.Using rat heterotopic heart isografts from bone marrow chimeras between cross-sex and applying polymerase chain reaction with specific primers to rat sex determining region of Y chromosome, a relationship between a state of microchimerism and induction as well as maintenance of acquired tolerance to H-Y antigen were examined.Microchimeric cells of the peripheral blood (MCPB) after cardiac grafting contain bone marrow-derived and radiation-sensitive cells. Furthermore, removal of the primary cardiac grafts revealed that microchimeric cells in the peripheral blood are long-lived cells, i.e., more than 6 months. When the female rats that had contained long-lasting MCPB, were innoculated with syngeneic male dendritic cells, failure to sensitize female toward male specific antigen H-Y was found to occur.Thus it was suggested that radiation-sensitive, bone marrow derived, long-lived MCPB play a significant role in maintaining acquired transplantation tolerance to minor histocompatibility antigen H-Y.

The value of apparent accommodation varies with methods of measurement. To discuss the details of apparent accommodation, it is appropriate to measure it with the smallest possible near vision optotype. In the present study, we used a 20/20 near vision optotype for the measurement of apparent accommodation.Forty-six eyes of thirty-eight patients (45-84 years old) who had undergone cataract surgery and intraocular lens implantation, and had at least 20/20 best corrected visual acuity at near and far distances, were used in this study. After the eyes were corrected by glasses to gain the best corrected long distance visual acuity, they were forced to watch a 20/20 near vision optotype. Then we gradually added plus lenses until they could recognize the optotype. The value of apparent accommodation was recorded by subtracting the value of plus lens by which the eye could first recognize the 20/20 near vision optotype from three diopters.The value of apparent accommodation was 0.00-3.00 D (medium 0.50 D). Two eyes had three diopters of apparent accommodation.In the present study with correction of astigmatism and small near vision optotype, most eyes showed smaller apparent accommodation than those in previous studies. Despite that, patients with three diopters of apparent accommodation do exist. To analyze high quality visual functions, we should use the smallest possible near vision optotype for the measurement of apparent accommodation.

We describe a single-center experience of 23 consecutive patients (median age, 35 years) with hematologic malignancies who received allogeneic peripheral blood stem cell transplants (alloPBSCTs) from HLA-identical siblings. Ten patients had standard-risk disease and 13 had high-risk disease. Twenty-one patients received alloPBSCT as a primary transplant, and the remaining 2, with high-risk disease, as a second transplant after posttransplantation relapse. All donors received daily subcutaneous injections of granulocyte colony-stimulating factor at a dose of 10 microg/kg, and peripheral blood stem cells were collected by 1 to 3 aphereses. Median numbers of CD34+ and CD3+ cells infused were 5.8 x 10(6)/kg (range, 1.3-19.7 x 10(6)/kg) and 4.9 x 10(8)/kg (range, 1.9-8.6 x 10(8)/kg), respectively. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporin A (CyA) and methotrexate (18 patients) or CyA and methylprednisolone (5 patients). Rapid hematologic engraftment was observed in 20 of the 23 patients. Median days to absolute neutrophil counts0.5 x 10(9)/L and platelet counts20 x 10(9)/L were 12 (range, 9-18 days) and 14 (range, 10-128 days), respectively. Acute GVHD of grade 2-4 was observed in 6 of 20 evaluable patients (30%) and extensive chronic GVHD in 8 of 15 evaluable patients (53%). Ten of the 23 patients (44%) were surviving in continuous complete remission 191 to 1492 days (median, 643 days) posttransplantation. Treatment-related death within 100 days posttransplantation was observed in 6 of the 23 patients (26%). Six of the 23 patients (26%) developed relapse at a median 81 days (range, 38-160 days) posttransplantation. Further study is needed to assess the precise benefits of alloPB-SCT compared with allogeneic bone marrow transplantation.

We encountered seven cases of pulmonary paragonimiasis. All patients were adult males and 6 of 7 cases were over 50-year-old. Except for one case of chronic pleural empyema, 6 patients were referred to the department of surgery because of having a mass lesion on chest roentgenography which was indistinguishable from malignancy. Although 3 patients had mild hemoptysis, none of them showed classical rusty sputum. Only one patient had high level of eosinophilia, whereas others showed normal or marginal level of eosinophilia. Paragonimus eggs were detected in transbronchial lung biopsy specimens from 4 patients. All patients' sera were positive for Paragonimus-specific IgG antibody by immunodiagnosis. Surgical option was undergone only for one patient with chronic pleural empyema which was not cured by repeated chemotherapy. In the present series, we could avoid surgical options due to an erroneous diagnosis. When a pulmonary mass lesion or empyema is detected in patients who live in paragonimiasis endemic areas, paragonimiasis should always be included in the different diagnosis of lung diseases.

A 15 year old female with uterus bicornis bicollis was admitted for operation. She had a history of atopic dermatitis and allergy to buckwheat, raw egg and latex. Two months previously she had developed whole body flushing during dental treatment, and latex glove used by the dentist had been suspected as the cause. Prior to the operation she underwent internal examination and intrauterine echogram in which a latex glove was carelessly used by another gynecologist who had not confirmed her past history. After 30 minutes, dyspnea and urticaria without itching, appeared suddenly. Blood pressure decreased to 80/50 mmHg and heart rate increased to 120 beats.min-1. She was then transferred to our ICU. Methylprednisolone was administered intravenously for dyspnea and circulatory collapse. After 3 hours, the patient made an uneventful recovery. The increased plasma latex protein-specific IgE levels confirmed anaphylaxis to latex. The increasing incidence of potentially life-threatening allergic reactions to latex has caused mounting concern over recent years. We may suspect latex allergy when an anaphylaxic reaction or shock of unknown origin occurs. In hospitals, latex free products must be prepared for use with latex allergic patients and for protection of medical staff with this allergy.

During 1986-1998 we found 104 paragonimiasis cases, which were referred to our laboratory for immunodiagnosis or identification of parasite eggs in sputum or bronchoscopic aspirate smears, or in histopathological sections. A majority of patients were middle-aged males. Except for 2 cases of chronic occult infection in an unexpected site, 102 cases were assumed as having active infection. Abnormal findings in chest radiograms were noted over 80% of the patients, though about 20% of them were asymptomatic. Parasite egg detection rates in sputum or bronchoscopic aspirate smears were about 50%. About 80% of patients have eosinophilia and/or elevated serum IgE level. Paragonimiasis is a re-emerging public health issue in Kyushu, Japan.

A 28-year-old man who had received an allogeneic bone marrow transplant 7 years earlier experienced a relapse of chronic myelogenous leukemia in an accelerated phase. He was unsuccessfully treated with vincristine (VCR) and interferon-alpha (IFN-alpha), and subsequently received a donor leukocyte transfusion (CD3+ cells: 1.5 x 10(7)/kg). Rapid hematologic recovery was observed and a complete remission was obtained without graft-versus-host disease (GVHD) or bone marrow aplasia. It may be that the preceding regimen of chemotherapy (VCR + IFN-alpha) contributed to the patient's recovery by reducing the tumor burden.

Pathogenicity and lethality of Neodiplostomum seoulense to various strains of mice (mast cell-deficient W/Wv, their normal littermate +/+, C57BL/6, BALB/cA, C3H/HeJ), and a hybrid (BALB/cA x C3H/HeJ)F1 were investigated. When the mice were infected orally each with 200 metacercariae, their abdomen became distended, and all mice died by day 23 postinfection (PI) except BALB/cA, which were severely weakened but recovered after 28 days. Even a smaller infection dose of 25 metacercariae was highly lethal to C3H/HeJ mice. Despite treatment with praziquantel (3 mg/mouse) on day 10 PI, 80% of C57BL/ 6 mice did not recover and died. After day 14 PI, the whole intestine of C57BL/6 mice was contracted and significantly shortened in length, and charcoal meal transit was significantly faster compared with uninfected controls. After incubation in papaverine, the contracted intestines of C3H/HeJ mice did not relax, suggesting that the change is irreversible. In conclusion, N. seoulense has the potential to kill most strains of mice by causing irreversible damage to their intestine. The effects of mucosal mast cells on the survival rate of mice were negligible, because both W/Wv and +/+ mice died around day 20 PI.

The production of granulocyte-macrophage colony-stimulating factor (GM-CSF) by lymphocytes was examined in murine malaria. When spleen cells or lymph node cells from P. berghei-infected mice were cultured in vitro with malaria antigen, the GM-CSF production correlated with the incubation time up to 72 hours. When lymphocytes obtained at various days after infection were cultured with the antigen, GM-CSF became detectable as early as 2 days after infection, reached a peak at day 9 and then rapidly decreased. Production of GM-CSF was antigen-specific, and related to the dose of antigen. Treatment of lymphocytes with anti-Thy-1.2 antibody and complement resulted in almost complete loss of GM-CSF-producing activity, while treatment with either anti-CD4 or anti-CD8 antibody and complement resulted in partial loss of GM-CSF-producing activity, indicating that both CD4+ and CD8+ T cells are involved in GM-CSF production in malaria. GM-CSF exhibits glycoprotein nature, and has an apparent molecular weight of 36,000. The molecular properties of this T-cell derived GM-CSF were compared with those of known lymphokine GM-CSF.

Recently several inbred strains of mice were found to be hyporesponsive to Interleukin (IL)-3 because of a 5-bp deletion in the intron 7 of the gene that encodes IL-3 receptor alpha subunit (IL-3R alpha). Due to this mutation, mast cells were not generated in vitro from bone marrow cells of these mice under the presence of IL-3. Intestinal mucosal mast cells, of which growth/differentiation is dependent on IL-3, are important effector cells in immune-mediated expulsion of intestinal nematodes, Stronglyoides spp. In the present study, therefore, we examined intestinal mast cell response and mucosal defence against Strongyloides venezuelensis in IL-3-hyporesponsive C58/J and A/J mice. After subcutaneous inoculation with 10,000 infective larvae, C58/J and IL-3-responsive C57BL/6 mice showed identical kinetic patterns of daily faecal egg output and intestinal mast cell response. When these mice were infected with 3000 L3 and, five weeks later, they were challenged by intraduodenal implantation of 800 S. venezuelensis adult worms, the timing of logarithmic decline of faecal egg count as well as intestinal mastocytosis was delayed for two days in C58/J mice. Kinetics of intestinal mastocytosis and faecal egg excretion after a primary and challenge infection in A/J mice, another IL-3-hyporesponsive strain, were identical with those seen in C58/J mice. These results suggest that intestinal mast cell response and mucosal defence against S. venezuelensis of the mutant mice were almost completely compensated in vivo. Possible mechanisms of induction of intestinal mast cell response in IL-3R alpha-defective mice are discussed.

Polyvinylacohol (PVA) gel cross linked by gamma irradiation was assessed as a possible vitreous substitute. In our previous, reports, elevation of intraocular pressure and inflammatory changes in the vitreous cavity after operation were observed in some of the experimental animals. Four types of PVA gel (sol) were produced by a newly refined method. We improved the gel systhesis process to remove the monomer and contamination. Colored rabbits were used for this experiment. Vitreous replacement was performed after vitrectomy. This was followed clinically by ophthalmoscopy, tonometry, fundus photography, electroretinogram, chemotaxis, and laser-flare-cell-metering. Histopathological examination by light microscopy was performed after 3 months. PVA gel has good biocompatibility in the vitreous cavity, and gel with a network similar to that of the vitreous body showed the best biocompatibility. Although it is necessary to investigate the biocompatibility over the long term and to evaluate the tamponade effect, PVA gel will be a bood candidate for a vitreous substitute.

We conducted a comparative study on a daily single versus a divided dose of G-CSF for G-CSF-induced mobilization of peripheral blood stem cells (PBSC) in eleven HLA-identical sibling donors of allogeneic PBSC transplantation (PBSCT). Six donors received double subcutaneous injections of G-CSF at a dose of 5 micrograms/kg x 2/day for 5 days (Group A), while the remaining five received single subcutaneous injection at a dose of 10 micrograms/kg/day for 5 days (Group B). The numbers of circulating CD34+ cells, myeloid progenitors (CFU-GM) and erythroid progenitors (BFU-E) reached peak values at day 5 of G-CSF administration in both groups. The mean number of CD34+ cells harvested per apheresis was 4.4 x 10(6)/kg (cells/body weight of each donor, range: 0.8-7.9 x 10(6)/kg) in Group A and 5.1 x 10(6)/kg (range: 3.0-9.0 x 10(6)/kg) in Group B. There were no significant differences between these two groups in total numbers of CFU-GM, BFU-E, or T-lymphocytes harvested. Adverse effects including mild to moderate bone pain and thrombocytopenia were transient and well tolerated. No difference was observed in the incidence of adverse effects between the two groups. These observations suggest that there is no difference in G-CSF-induced mobilization of PBSC between daily single and divided dose of G-CSF to collect a sufficient number of PBSC for engraftment after allo-PBSCT.

Ascariasis has been a representative soil-transmitted intestinal parasitic disease in warm climates. In Japan, this disease was a major and serious public health problem only a few decades ago. However, the incidence of the disease nowadays is reportedly less than 0.01%. Recently in 1994 through 1995, we experienced a total of 14 cases who were suspected as having ascariasis. They were characterized by peripheral blood eosinophilia (30-70%), high serum titers against Ascaris antigen, and most notably, they were absolutely negative for Ascaris eggs in repeated fecal examinations. Specific antibody titers against Ascaris antigen correlated well with the degree of eosinophilia. All patients were living in narrow areas of Kyushu, Japan, where a lot of porcine farms were located. Most of the patients were asymptomatic and pointed out to have eosinophilia during follow-up studies of chronic diseases or in regular check-up. Only one patient had a clear sign of Löffler's syndrome and another had subcutaneous eosinophilic granuloma. However, laboratory examinations revealed moderate liver dysfunction in 7 patients and pulmonary infiltrations in 5 patients. Based on circumstantial and serological evidence, these patients were diagnosed as having been infected with Ascaris lumbricoides suum, a swine Ascaris.

Development of basophilic leukocytes was studied in the Mongolian gerbil, Meriones unguiculatus, after infection with the nematode Nippostrongylus brasiliensis. After infection, peripheral blood basophilia developed and peaked at 2 weeks. In bone marrow sections, numbers of alcian blue+/safranine- basophilic cells were increased. These cells did not bind berberine sulfate and were clearly distinguishable from the bone marrow-resident mast cells, safranine+ and berberine sulfate+. Alcian blue+/safranine- cells were identified by electron microscopy as basophilic myelocytes in various stages of maturation. In the early period of infection, these cells had round-to-oval granules with a homogenous electron-dense matrix, a well-developed Golgi apparatus and rough endoplasmic reticulum, and a nonsegmented nucleus. By enzyme cytochemical analysis, intense peroxidase activity was demonstrated in all of the specific granules as well as in the rough endoplasmic reticulum and Golgi apparatus. Two weeks after infection, the number of bone marrow basophilic cells further increased, forming distinct clusters or islands composed of up to 100 cells each. On electron micrographs, the basophilic cells in these clusters appeared to be late-stage basophilic myelocytes, ie, having an increased number of granules, a less-conspicuous Golgi apparatus and rough endoplasmic reticulum, a horseshoe-shaped-to-lobulated nucleus, and reduced peroxidase activity. Eosinophils and mast cells were rarely found in the basophilic cell clusters. Four weeks after infection, the clusters had disappeared. These results show that gerbil basophilic myelocytes tend to form cell clusters in the bone marrow during their active proliferation. The comparative paucity of other cell lineages in basophilic cell clusters suggests that basophilia is generated from differentiation/proliferation of precommitted basophil progenitors independently from cells of other lineages.

Gnathostomiasis is an important food-borne parasitic zoonosis caused mainly by ingesting uncooked or undercooked flesh of freshwater fishes. Although four distinct species of the genus Gnathostoma were identified as the causative agents for human gnathostomiasis, human infections with G. doloresi have been found only in Japan, concentrated in Miyazaki Prefecture. So far we have found 25 cases in Miyazaki Prefecture. Although most of these patients were of cutaneous gnathostomiasis, two patients presented to the hospital with unusual clinical manifestations; one case was a pulmonary gnathostomiasis diagnosed by immunoserological methods, and the other was an ileus caused by migration of the late 3rd stage larva in the colonic tissue, which was found by post-operative histopathological examination. Although cutaneous lesions such as creeping eruption or mobile erythema are the common clinical features of gnathostomiasis, caution should be paid to the presence of such unusual cases.

A cDNA encoding rat mast cell tryptase (rMCT) was successfully cloned, and sequenced, from peritoneal cells of Lewis rats infected with Nippostrongylus brasiliensis by the reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends methods. The cDNA was 1,097 base-pairs long, and included 822 base-pairs of an open reading frame. As judged from the deduced amino acid sequence, rMCT is highly homologous to mouse mast cell protease-6, and is considered to be translated as a prepro-enzyme with a 19-amino acid signal peptide, a 10-amino acid activation peptide, and a 245-amino acid mature enzyme. The rMCT mRNA was not detected in peritoneal cells of mast cell-deficient Ws/Ws rats, though it was strongly detected in ones of littermate +/+ and Lewis rats. In addition to in peritoneal mast cells, the rMCT mRNA was detected in the tongue. However, mRNA signals were not detected in the small intestine regardless of N. brasiliensis infection. Nor were mRNA signals detected in RBL2H3 rat basophilic leukemia cells. In the lung, the rMCT mRNA was strongly detected after infection with N. brasiliensis, though it was only faintly detected before infection. These results suggest that the rMCT is basically specific for connective tissue mast cells, but not for mucosal mast cells and that it is up-regulated in the lung during the inflammatory process of a parasitic infection.

A cDNA encoding alpha 1-microglobulin (alpha 1mG)/inter-alpha-trypsin inhibitor light chain (ITI-LC) was cloned from mouse liver by reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends. Sequence analysis of the cDNA showed that the basic molecular structure of the proprotein was similar to that in other animals, so that two mature proteins, alpha 1mG and ITI-LC, could be produced from the proprotein translated from the mRNA. Since ITI-LC is known as a positive acute phase reactant and since ITI-LC is genetically identical with mast cell proteinase inhibitor, trypstatin, we examined the mRNA level in the liver of parasite-infected mice showing extensive mastocytosis. The mRNA level was, however, not significantly changed during inflammatory processes, except for a slight increase on day 8 post-infection.

Mast cells in jejunum, skin, and tongue of Mongolian gerbils (Meriones unguiculatus) were examined in terms of their histochemical, enzyme-histochemical, and ultrastructural properties. When glycosaminoglycans of mast cells in jejunum and tongue were characterized by measuring the critical electrolyte concentration, the salt concentration at which 50% of mast cells could be stained was1.0 M for those in the jejunum and also in the tongue, indicating that mast cells in both sites contained heparin. Enzyme-histochemical study revealed that mast cells in the jejunum of Mongolian gerbils were strongly positive for chymase and tryptase, whereas those in tongue and skin were essentially negative for both proteases. By electron microscopy, granular morphology and distribution of surface microfolds of mast cells in the jejunum were different from those in the ear skin. After in vivo stimulation with compound 48/80, however, mast cells in both sites showed remarkable degranulation. From these results, although Mongolian gerbils also have distinct mast cell subsets, their phenotypic properties are different from those of the previously known mast cell subsets of other animals.

The immune responsiveness to specific antigens or mitogens was examined in jirds after primary and secondary infections with Brugia pahangi. When spleen cells were obtained from secondarily infected jirds, their proliferative responses to mitogens such as Con A or LPS, or to specific antigens prepared from infective larvae or adult worms were significantly lower than those of spleen cells obtained from primarily infected jirds. The proliferative responses of the peripheral blood mononuclear cells obtained from animals undergoing primary and secondary infections also showed a similar tendency. The depressed proliferative responses of the secondary infected spleen cells to Con A or LPS was partially restored by removing adherent/phagocytic cells from the original cell populations. After deletion of the adherent cells, however, antigen-specific proliferative responses were not altered and remained at low level. These results suggest that at least two different mechanisms of depression, namely adherent cell-mediated antigen-nonspecific suppression and unresponsiveness of lymphocytes to filarial antigens, are induced in jirds in the secondary infection.

The aim of this study was to examine the role of T cells on the alteration of terminal sugars of goblet cell mucins in the small intestinal mucosa of parasitized rats and to clarify the biological significance of the altered mucins in the mucosal defence against intestinal helminths. For this purpose, Nippostrongylus brasiliensis adult worms obtained from donor rats at 7 ('normal' worms) or 13 days ('damaged' worms) post-infection were implanted intraduodenally into euthymic and hypothymic (rnu/rnu) rats. Expulsion of implanted normal worms and associated goblet cell changes were extremely delayed in hypothymic recipients compared with euthymic recipients. In contrast, intraduodenally implanted damaged worms were expelled by day 5 regardless of the strains. Around the time of expulsion of implanted damaged worms, euthymic recipients showed both goblet cell hyperplasia and alteration of mucins, whereas hypothymic rats showed only the latter. Dexamethasone treatment completely abolished goblet cell changes of both strains of recipients. To clarify the importance of the constitutional changes of goblet cell mucins in mucosal defence, euthymic rats were primed by implantation of damaged worms to induce goblet cell changes, and then 3 or 5 days later they were challenged by implantation with normal worms. The results show that when goblet cell changes were induced by priming with damaged worms, recipient rats could completely prevent the establishment of normal worms. When hypothymic rats were primed and challenged in the same manner, a similar but slightly less preventive effect was observed. Such a protective effect of altered mucins seems to be selective because priming of euthymic rats with damaged N. brasiliensis did not affect the establishment of Strongyloides venezuelensis. These results suggest that: (1) once N. brasiliensis adult worms are 'damaged' by the host's T-cell-dependent immune mechanisms, they can induce alteration of sugar residues of goblet cell mucins via host-mediated, T-cell-independent processes; (2) the expression of such altered mucins is highly effective not only in causing expulsion of established damaged worms but also in preventing establishment of normal worms; and (3) the preventive effect of altered mucins is selective against parasite species.

Alteration of terminal sugars of goblet cell mucins in the small intestinal mucosa was examined by lectin histochemistry in rats infected with Nippostrongylus brasiliensis. To see whether alteration of the nature of mucins was regulated by the local immune system, adult worms were implanted intraduodenally into recipient rats of various immune status. When 7-day-old ('normal') adult worms were implanted into naive euthymic rats, about 60% remained until day 7 and then were expelled. The number of goblet cells transiently decreased on day 5 and then progressively increased from day 9 onwards. In parallel with the hyperplasia, mucins in and released from goblet cells strongly expressed terminal N-acetyl-D-galactosamine which was specifically recognized by Helix pomatia agglutinin (HPA). When 13-day-old ('damaged') adult worms were implanted into naive euthymic rats, they were rapidly expelled by day 9 in association with hastened goblet cell hyperplasia and the alteration of terminal sugars of the mucins. Hastened worm expulsion, goblet cell hyperplasia and alteration of terminal sugars of the mucins were also observed when 'normal' worms were implanted into immune recipients. On the other hand, after implantation of 'normal' worms into hypothymic (rnu/rnu) rats, goblet cell hyperplasia or the alteration of terminal sugars of the mucins was almost completely absent. These results suggest that alteration of sugar residues of goblet cell mucins, especially the strong expression of terminal N-acetyl-D-galactosamine, is regulated by the host's immune system and seems to be important in the expulsion of N. brasiliensis.

We examined the effect of adherent cells from bone marrow or spleen of mice infected with Plasmodium berghei on dyserythropoiesis. Significant reduction in number of erythroid progenitors (erythroid colony-forming units: CFU-E and erythroid burst-forming units: BFU-E) was observed in bone marrow as early as 1 day after P. berghei infection. When adherent cells were removed from bone marrow or spleen cells of infected mice, the number of CFU-E and BFU-E was clearly increased. Furthermore, addition of adherent cells from infected mice to nonadherent cells from normal mice inhibited erythroid colony formation significantly in a dose-dependent manner. These results suggest that the adherent cells obtained from bone marrow or spleen of mice in the early stage of P. berghei-infection have a suppressive effect on erythropoiesis.

A repetitive administration of recombinant interleukin-3 (rIL-3), which can induce the expulsion of Strongyloides ratti in athymic nude mice, did not affect the expulsion of Nippostrongylus brasiliensis. Nude mice infected with N. brasiliensis were injected i.p. with a total of 6.8 x 10(5) U rIL-3 or medium twice a day from Day 5 to Day 11 post-infection. The kinetics of expulsion estimated by egg excretion in faeces up to Day 20 post-infection and adult worm burden on Day 21 was not affected by the IL-3 administration. A similar administration with a higher dose (total 10.6 x 10(5) U) of rIL-3 did not alter the adult worm burden on Day 13. The number of intestinal mucosal mast cells on Day 13 was markedly increased by the treatment, although the number of intestinal goblet cells was comparable between the treated and control mice. When nude mice were infected concurrently with N. brasiliensis and S. ratti and then injected repeatedly with rIL-3 (total 2.2 x 10(5) U) from Day 5 to Day 11, adult worms of S. ratti were expelled from the small intestine by Day 13; however adult worms of N. brasiliensis were retained. Again in the concurrent infection, the number of intestinal mucosal mast cells was significantly increased but that of intestinal goblet cells was not altered by the rIL-3 administration. These results indicate that the expulsion of S. ratti is dependent on IL-3 whereas that of N. brasiliensis is less dependent on IL-3.

Histochemical stainability of mast cells in the small intestine of Mongolian gerbils, Meriones unguiculatus, was examined before and after infection with Nippostrongylus brasiliensis, a well-known intestinal helminth inducing intestinal mastocytosis in rats and mice. Mast cells seen in the small intestine of Mongolian gerbils were exclusively formalin-resistant and were strongly stained by berberine sulfate, regardless of whether the animals were normal or infected with N. brasiliensis. Furthermore, they were, either normal or induced by infection, only seen in the lamina propria and submucosa but never seen in the jejunal epithelium. Such histochemical properties and distribution of intestinal mast cells of Mongolian gerbils were different from previously known characteristics of mast cells in the small intestine of rats and other animal species.

Extramedullary hemopoiesis, recognized as hemopoietic foci, increased in the livers of Toxocara canis-infected mice. At the peak of the response (day-13 after infection), the majority of hepatic hemopoietic foci were of the eosinophil lineage. Hepatic nonparenchymal cells prepared from T. canis-infected mice on day 13 contained large numbers of hemopoietic stem cells, more than half of which were cycling. When W/Wv mice, which are genetically deficient in multipotent hemopoietic stem cells, were infected with T. canis, hepatic hemopoietic foci were rare throughout the course of infection. This impaired response of W/Wv mice was restored by bone marrow grafting from normal +/+ littermates. These results indicate that, in response to the increased demand, eosinophils are generated in the liver by the differentiation from multipotent stem cells, not only from the committed precursors.

Release of eosinophil chemotactic factor (ECF) from murine bone marrow derived cultured mast cells was examined. As the indicator cells for in vitro chemotaxis assay, eosinophils were obtained from bone marrow of cyclophosphamide-treated and Toxocara canis-infected mice. When cultured mast cells were stimulated with calcium ionophore A23187 or IgE-antigen, they released ECF as well as beta-hexosaminidase. ECF-release was not observed when they were stimulated with compound 48/80. Freeze-thawed extract of cultured mast cells contained beta-hexosaminidase but no ECF activity, showing that the ECF is newly synthesized after stimulation. ECF was even spontaneously released when cultured mast cells were incubated for more than 30 min at 37 degrees C. The ECF released from cultured mast cells was low molecular weight substance (less than 1300 Dalton), and was resistant to digestion with carboxypeptidase. The ECF was extractable into chloroform-methanol (2:1) at acidic pH. Judging from these physicochemical characteristics, ECF released from cultured mast cells may be an arachidonic acid metabolite.

In this review, we have demonstrated three major facets of the eosinophilic mechanism in parasitic infections. Firstly, eosinophilia is primarily a matter of cell differentiation and/or maturation from hemopoietic stem cells. During infections with tissue-invading parasites, large numbers of pluripotent hemopoietic stem cells are generated, and mobilized to extramedullary hemopoietic sites such as the liver, where they become mature eosinophils in response to the increased demand.

The role of mast-cell-derived eosinophil chemotactic factor A (ECF-A) on eosinophil-rich periovular granuloma formation was examined by using mast-cell-deficient WBB6F1-W/WV mice infected with Schistosoma japonicum. The average size of granulomas formed around newly deposited eggs in the liver of W/WV mice was significantly smaller than that observed in control +/+ mice. The number of adult worms recovered or specific IgE titers were comparable between W/WV and +/+ mice. In contrast, immediate-type hypersensitivity response to specific antigen and dialyzable low-molecular weight ECF in the serum was detectable only in infected +/+ mice. When naive bone marrow eosinophils were incubated with the dialyzable fraction of infected +/+ mice sera, chemotactic reactivity of eosinophils to ECF derived from S. japonicum eggs was significantly enhanced, although that to synthetic ECF-A was depressed. Similar effects were observed when naive eosinophils were treated with synthetic ECF-A. The dialyzable fraction of infected W/WV mice sera had no such modulating effect on the chemotactic reactivity of eosinophils. These results suggest that an immediate-type hypersensitivity reaction is important in the formation of eosinophilic granulomas around S. japonicum eggs, mainly through the modulating effect of mast-cell-derived ECF-A on the chemotactic reactivity of eosinophils.

The effects of Toxocara canis infection on hemopoietic stem cells and hemopoietic factors were examined in mice. Severe eosinophilia was observed with a peak 14 days after infection. When the numbers of hemopoietic stem cells in peripheral blood, spleen, and bone marrow were examined by spleen colony assay (CFU-S), those in peripheral blood and spleen increased in parallel with peripheral blood eosinophilia. On the other hand, CFU-S in bone marrow did not alter significantly throughout the course of infection. Interleukin (IL)-3, which is known as multi-colony-stimulating factor and is involved in the growth/differentiation of various blood cells including stem cells, was produced by spleen cells of infected mice. The time course study showed that concanavalin A stimulated IL-3 production peaked on day 7 after infection, whereas that with excretory secretory antigen peaked on day 14. Even without stimulation, spleen cells obtained on day 21 after infection produced IL-3 spontaneously. IL-5, which is known to have eosinophil differentiation factor activity, was also produced by spleen cells obtained on day 13 after infection. These results suggest that in response to increased demand for eosinophils, hemopoietic stem cells migrate into various extramedullar hemopoietic organs where they grow/differentiate into mature eosinophils, depending on the hemopoietic factors.