Behaviors of mice given forced-swimming.

Behaviors of mice in the forced swimming test are motionlessness, climbing and the other stereotypical behaviors. We observed these behaviors in different ages and sex and in repeated forced swimming trials. The findings were 1) quantities of the climbing and the other behaviors were different with the age and sex, 2) repeated per day forced swimming remarkably increased motionlessness and motionlessness is memorized for at least 14 days, and 3) climbing is the typical opposite behavior of motionlessness and was related to adrenergic but not serotonergic neuronal activity. When these behaviors are recognized as adaptation behaviors, we conclude that mice given repeated forced swimming, but not mice given one trial of forced swimming, can be considered as a model of human depression relating to adrenaline neuronal activity.

Digging behavior of ddY mouse.

In the present studies, the behavior of ddY mice digging wood chips was carefully observed. When mice were individually placed on new 5 cm-thick wood chips, their behavior was found to be the same irrespective of their age or sex. The behavior was not prevented by non-noxious 5 black steel rods which were used to measure digging ability, and was not related to habituation or learning. But moist or dirty chips remarkably weakened digging ability. These findings strongly suggest that the digging behavior is a natural and instinctive one, but not an expression of anxiety as previously reported.

The influence of Mesocestoides corti on subsequent Angiostrongylus cantonensis infections in mice.

The influence of Mesocestoides corti on subsequent Angiostrongylus cantonensis infection in mice (C57BL/6 and BALB/c) was assessed. Both strains of mice infected with M. corti demonstrated a peak blood eosinophilia at around 3 weeks post-infection (p.i.). C57BL/6 and BALB/c mice primarily infected with M. corti were given A. cantonensis infection 18 days later, but pre-existing M. corti infection did not affect the recovery of intracranial worms of A. cantonensis at day 21 p.i. BALB/c mice with mixed parasite infections showed low morbidity and mortality as compared with mice singly infected with A. cantonensis and some mice demonstrated a pulmonary migration of intracranial worms. In C57BL/6 mice, intracranial worms were killed and thus all mice survived. C57BL/6 mice with mixed parasite infections failed to resist A. cantonensis reinfection. The blastogenic responses of spleen cells against A. cantonensis antigen were lower in BALB/c than in C57BL/6 mice and mixed parasite infections also resulted in less blastogenic responses against both concanavalin A and A. cantonensis antigen than monoinfection. The recovery of M. corti biomass was significantly higher in mice with mixed parasite infections than mice with monoinfection with M. corti. These data suggest a distinct difference in response to A. cantonensis infection between C57BL/6 and BALB/c mice, and the induction of immunosuppression in both mouse strains following M. corti infection. Blood eosinophilia provoked by M. corti infection is not directly associated with the killing of worms in subsequent A. cantonensis infection.

[A study of cerebral hemodynamics using transcranial Doppler ultrasonography with special reference to clinical evaluation of pulsatility index].

Transcranial Doppler Ultrasonography (TCD) is now commonly used to evaluate the cerebral hemodynamics. However, the blood velocity measured with TCD is not always accurate, because as a rule the direction of the blood flow does not completely coincide with that of the ultrasonic beam. The error in the measurement could be as large as 15%. This could be eliminated by calculating pulsatility index (PI) from the Doppler ultrasonography. This study evaluates the reliability of the PI as an index of cerebral hemodynamics. In total, 164 measurements were made in patients with various cerebrovascular diseases (CVD), including 14 of brain death patients (group B) and 14 of inpending herniation patients (group I). Of CVD, 46 were persistent vegetative state patients (group V), and 43 were in relatively good conditions (group A). Other including 15 of hydrocephalus patients (group H) and 19 of cerebral vasospasm after subarachnoid hemorrhages (group S) were also investigated. Nineteen normal young volunteers (group N) were used as controls. The mean level of PI in group N shows 0.82. PI in group A was increased to 1.04, and in group V, 1.27. Furthermore in the brain death group, the mean level of PI was increased to 3.86, which was statistically significant. It was concluded that measurement of PI was very useful to evaluate the changes of cerebral hemodynamics, and the levels of PI was affected more with the changes in diastolic than in systolic flow velocity.

Application of alcohol- or acetone-fixed Schistosoma eggs as an alternative to lyophilized eggs for the circumoval precipitin test.

Antigenicity of Schistosoma mansoni and S. japonicum eggs preserved in ethanol or acetone were assessed in a circumoval precipitin (COP) assay. The egg antigens were found to retain sufficiently their COP reactivity for the diagnosis of both schistosomiasis mansoni and japonica, although their reactivity became lower than that of lyophilized eggs. These alternative preparations for COP tests have advantages, such as keeping eggs directly in fixatives soon after the egg-purification process. Furthermore, evaporation-process may cause eggshell cleavages which facilitate the reaction. The possible usefulness of those eggs in COP assays in local endemic areas is discussed.

Apodemus sylvaticus, a new host for Acanthocheilonema viteae (Nematoda: filarioidea).

Susceptibility of Apodemus sylvaticus and A. agrarius to infection with Acanthocheilonema viteae was compared with that of hamsters and jirds. Microfilaremia in A. sylvaticus was first noted on day 52 post-infection (p.i.) and lasted during the course of the study (up to day 150 p.i.). Maximum microfilaremic levels (female worm basis) of A. sylvaticus [mean +/- S.D. (n) = 690 +/- 1288(6)] were considerably higher than those of hamsters [16 +/- 18(6)] and jirds [51 +/- 25(5)]. Adult worm recovery in A. sylvaticus ranged from 2 to 40% of the number of infective larvae inoculated. Worm development in A. sylvaticus resembled that in hamsters and jirds. In contrast, microfilaremia was not detected in, nor adult worms recovered from A. agrarius throughout the study.

Protective immunity against Angiostrongylus cantonensis in rats following sensitizing infections.

Three strains (ACI, August and Wistar) of rats previously sensitized by oral infection with intact third-stage larvae of Angiostrongylus cantonensis developed significant protective immunity to challenge infections 6 weeks later. The degree of the immunity was highest in the August strain of rats, followed by Wistar and ACI rats. Protective immunity appears to affect both third-stage larvae and fourth- and/or fifth-stage worms. ACI rats showed poor antibody responses, especially in the IgE fraction. When 24-day-old young adult worms were transferred from the brain of donor rats into the peritoneal cavity of sensitized rodents, peritoneal eosinophils predominantly adhered to the worm surfaces in vivo.

Cytologic demonstration of Entamoeba histolytica using immunoperoxidase techniques. Report of two cases.

An indirect immunoperoxidase technique to detect Entamoeba histolytica in cell samples from patients suspected to have amebiasis is described. Using a rat antiserum specific for E. histolytica, the organism was clearly identified both in smears and in cell blocks. This immunoperoxidase technique seems to offer great possibilities for a specific, accurate and rapid identification of amebic infestation in diagnostic cytology.

[Diphyllobothrium latum infection in Akita Prefecture. Infections occurring from 1974 to 1981 and the clinical effect of paromomycin sulfate].

Forty-one patients, aged 2 to 68 years old, infected with Diphyllobothrium latum in Akita prefecture were treated using paromomycin sulfate from 1974 to 1981. Paromomycin sulfate was administered orally in a single dose of 20, 30 mg/kg or 50 mg/kg. Twenty-three cases expelled tapeworms. However, only 9 (28.1%) out of 32 tapeworms expelled had their scolex. It can be said that all cases were successfully treated with paromomycin sulfate, since they showed the egg-negative on 3 weeks or 1 month after the treatment. The drug was well tolerated and no side effects were encountered in any patients. It was suggested that paromomycin sulfate was effective and also safe therapeutic agent for the treatment of D. latum infection.