Atsushi Hioki

Reduced fecundity of Hymenolepis nana due to thymus-dependent immunological responses in mice

Abstract Reduced fecundity of Hymenolepis nana due to thymus-dependent immunological responses in mice. International Journal for Parasitology 16 : 81–85. The fecundity of the dwarf tapeworm, Hymenolepis nana , was enhanced in congenitally athymic nude CD-1 (ICR) mice but depressed to the same degree as in phenotypically normal littermates when they were reconstituted with thymocytes before infection. The reduction in fecundity of this parasite was clear only when H. nana were recovered from those strains of mice which demonstrate a “late response” against luminal cysticercoid challenge before the established worms become fully mature (within 15 days of initial immunizing egg inoculation). The fecundity of H. nana in dd mice, which acquire the late response within 30–40 days, was greatly advanced than that in BALB/c or CD-1 (ICR) mice and somewhat better than even that in the nude CD-1 (ICR) mice and appeared to be little, or not at all, depressed. The fecundity and longevity of this parasite, highly variable among mouse strains, is discussed in terms of variations in the rapidity of expression of protective immunity against the lumen phase.

Significance of blood urea nitrogen as an index of renal function in mice infected withPlasmodium berghei

Parameters of renal function were evaluated in severe malarial infection, using mice infected withPlasmodium berghei. When 7-week-old male BALB/c mice were inoculated with 1×107P. berghei NK65-infected red blood cells, the rodents died an average of 7.4 days after inoculation. Anemia developed on day 5 after inoculation and progressed markedly on days 6 and 7. Plasma urea nitrogen increased rapidly on day 6 or 7, after which death occurred within 24 h. In contrast, urinary urea nitrogen excretion decreased on the same day. Urinary β-N-acetyl-d-glucosaminidase (NAG) activity increased from day 3 to day 5, then decreased to normal levels on day 7. Renal ATP concentration and energy charge decreased markedly on day 7. These data indicate that the blood oxygen supply to the tissues began to decrease on day 6 and that renal insufficiency developed in the terminal stage of infection. We concluded that even a moderate increase in the level of plasma urea nitrogen could be a useful index of renal insufficiency in this infection system.

Pathophysiology of hypoxia in mice infected with Plasmodium berghei

Pathophysiological significance of hypoxia in malarial infection was investigated in mice infected with Plasmodium berghei NK65. Intraperitoneal inoculation of mice with 1×107 parasitized red blood cells resulted in death of the hosts 6–7 days later. Anaemia of infected animals developed on day 4 after inoculation and oxygen affinity of whole blood, measured as P50 act pH, increased simultaneously. This change may be a physiological adaptive response to a reduction in oxygen delivery to the tissues to day 5. However, the blood oxygen supply on day 6 appeared to be deteriorating and this is thought to be an important factor contributing to the death of the host. The value of adenylate energy charge in red cells during malarial infection, however, was comparatively well-maintained. Allopurinol stimulated the multiplication of malaria parasites and seems to have induced collapse in host-parasite balance more rapidly. Decrease in blood pH and in blood oxygen transport may be important factors for the pathogenesis of the allopurinol-treated hosts.

Correlation between protective antibody response and patent infection with Hymenolepis nana in mice

Abstract Correlation between protective antibody response and patent infection with Hymenolepis nana in mice. International Journal for Parasitology16: 197–203. Mice inoculated with mouse-derived cysticercoids of Hymenolepis nana, as well as with eggs, produced IgG and IgE antibodies that were detected by double diffusion (DD) and passive cutaneous anaphylaxis (PCA), respectively. When mice inoculated with eggs (day 0) were challenged with eggs (day 66), all were resistant to the challenge (assessed by the failure of cysticercoid recovery in the intestinal tissue) and produced protective antibodies evidenced by passive transfer, as well as IgG and IgE isotypes. When mice inoculated with eggs (day 0) were treated with a highly efficacious cestocide, praziquantel on day 6 at the beginning of the lumen phase, all were also resistant to the egg challenge on day 66, however, IgE, IgG, and protective antibodies were not detected. When mice treated with praziquantel before patent infection were repeatedly challenged with high doses of eggs, some of them produced IgG and IgE antibodies. From these results, it is suggested that (1) the production of protective antibody is a secondary response after patency (which may be ascribed to eggs released from mature worms), and (2) mice initially given eggs are highly resistant to egg challenge showing that an effector mechanism of acquired resistance to egg challenge may be expressed without high titres of protective antibody, at least in the serum.

Suspended particle and drug ingredient concentrations in hospital dispensaries and implications for pharmacists' working environments.

ObjectivesThe aim of this study was to assess the present status of working environments for pharmacists, including the concentrations of suspended particles and suspended drug ingredients in dispensaries.MethodsWe conducted a survey on the work processes and working environment in 15 hospital dispensaries, and measured the concentrations of suspended particles and suspended drug ingredients using digital dust counter and high-performance liquid chromatography tandem mass spectrometry (LC–MS/MS), respectively. Of 25 types of powdered drugs that were frequently handled in the 15 dispensaries surveyed, 11 could be quantitatively determined.ResultsThe amounts of suspended particles were relatively high, but below the reference value, in three dispensaries without dust collectors. The sedative-hypnotic drug zopiclone was detected in the suspended particles at one dispensary that was not equipped with dust collectors, and the antipyretic and analgesic drug acetaminophen was detected in two dispensaries equipped with dust collectors. There was no correlation between the daily number of prescriptions containing powdered drugs and the concentration of suspended particles in dispensaries.ConclusionOn the basis of the suspended particle concentrations measured, we concluded that dust collectors were effective in these dispensaries. However, suspended drug ingredients were detected also in dispensaries with dust collectors. These results suggest that the drug dust control systems of individual dispensaries should be properly installed and managed.

Prevalence of subjective symptoms among hospital pharmacists and association with drug compounding practices.

In Japan, the principal role of hospital pharmacists has changed from that of dispensing medicines for outpatients to provision of clinical pharmacy services for inpatients. A self-administered questionnaire about subjective symptoms, working patterns, work environments and job satisfaction was administered to 495 hospital pharmacists and 84 prefectural office-based pharmacists (control group). The response rates were 63.4% and 90.5%, respectively. Hospital pharmacists showed a higher prevalence of nasal symptoms than that shown by the control office-based pharmacist group. The prevalence rate of nasal symptoms was lower only in male pharmacists who worked in a dispensary equipped with dust collector. The prevalence of symptoms noticed by hospital pharmacists and community pharmacists after starting drug compounding practices was also compared. The prevalence of subjective symptoms that pharmacists noticed after starting drug compounding was lower in hospital pharmacists than in community pharmacists. Job satisfaction was lower in hospital pharmacists than in office-based pharmacists; however, there was no clear association between the subjective symptoms reported and job satisfaction. Further studies on removal effect of drug dust in a dispensary and symptoms in individual pharmacy facilities are needed.

Clinical evaluation of antimalarial regimens in Japan.

The actual situation of the treatment of malaria for the past 10 years in Japan was investigated and analyzed. As a result, it was revealed that there were not a few cases which had been treated improperly probably because of the difficulty of getting antimalarial agents. Moreover, it was made clear that the death rate on falciparum malaria was constantly high, 8.7%, as expected and the relapse rate of vivax malaria was still as high as 18.0%. There was the recrudescence of falciparum malaria at 8.1%, maybe because of the influence of the prevalence of the drug-resistant strains of Plasmodium falciparum. The trouble in getting antimalarial agents has been overcome since 1980. Study Group on Pharmacotherapy of Imported Tropical Diseases was organized by the Ministry of Health and Welfare in 1980, and antimalarial agents have been supplied free of charge through the Study Group for the treatment of the disease. The number of cases of imported malaria has increased in our country. There are a lot of problems to be solved quickly to cope with the situation: people who travel abroad should be enlightened on the danger of the infection of malaria and take prophylactics for the disease and physicians should get familiar with the disease being supplied with information about it.