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Phenotypic change of blood-type eosinophils to tissue-type eosinophils is induced by various cytokines. We examined the effect of nerve growth factor (NGF) as a candidate for a constitutive cytokine which is able to induce the phenotypic change of eosinophils. The viability of human peripheral blood eosinophils cultured for 4 d was increased from a mean of 26% to a mean of 50% (P<0.001) by the addition of NGF (50 ng/ml). Cytotoxic activity of eosinophils determined by larvicidal activity was increased 2-3-fold by the addition of NGF (50 ng/ml) (P<0.05). Furthermore, eosinophil chemotactic activity of NGF was demonstrated by the blind well chamber method. Since NGF is produced constitutively from various kinds of cells in local tissues, it is suggested that NGF might be a cytokine responsible for phenotypic change to tissue type eosinophils in conditions without immune stimuli.

Summary:Correlations between Tl and T2 relaxation times and water and electrolyte content in the normal and ischemic rat and gerbil brains were studied by means of both nuclear magnetic resonance (NMR) spectroscopic and imaging methods. In the spectroscopic experiment on excised rat brains, Tl was linearly dependent on tissue water content and T2 was prolonged in edematous tissue to a greater extent than expected by an increase in water content, showing that T2 possesses a greater sensi tivity for edema identification and localization. Changes in Na + and K + content of the tissue mattered little in the prolongation of relaxation times. Serial NMR imaging of gerbil brains insulted with permanent hemispheric isch- Proton nuclear magnetic resonance (NMR)imaging enables sensitive detection of cerebral ischemia within several hours after the onset of dis ease (Buonanno et aI. , 1983; Mano et aI. , 1983; Spetzler et aI. , 1983). T1 (spin-lattice) and T2 (spin-spin) relaxation times are prolonged in isch emic tissue, and the degree of damage and extent of injury can be pictorialized by NMR imaging. Pro longation of relaxation times is considered to be a result of the development of brain edema (Go and Edzes, 1975; Naruse et aI. , 1982). However, the contrast of the NMR image is arbitrarily controlled by the pulse sequence used. As a consequence, the Abbreviations used: IR, inversion recovery; NMR, nuclear magnetic resonance; PO, proton density; SE, spin echo; SR, sat uration recovery; TE, time to echo; n, time of inversion; TR , time of repetition. 212emia offered early lesion detection in TJ-and especially T2-weighted images (detection as soon as 30 min after insult). The progressive nature of lesions was also imaged. Calculated TJ and T2 relaxation times in regions of interest correlated excellently with tissue water con tent (r = 0.892 and 0.744 for T 1 and T2, respectively). As a result, detection of cerebral ischemia utilizing NMR imaging was strongly dependent on a change in tissue water content. The different nature of Tl and T2 relax ation times was also observed.

The effect of jasplakinolide (JAS), an actin-polymerizing and filament-stabilizing drug, on the growth, invasion, and actin cytoskeleton of Plasmodium falciparum was examined. Jasplakinolide markedly decreased the parasitemia in a synchronized culture of P. falciparum strain FCR-3 in a time- and concentration-dependent manner. The decrease became evident at day 2 at concentrations of 0.3 micro M and above, and parasites finally disappeared at day 4. Giemsa-stained smears of P. falciparum-infected erythrocytes demonstrated that there was no effect on the development of schizonts from ring forms. Merozoites were released from the infected erythrocytes in a normal manner with and without JAS. However, there were no ring form-infected erythrocytes when JAS was administered, even after the release of merozoites. This indicates that the merozoites exposed to JAS failed to invade erythrocytes. The inhibitory effect of JAS on the parasitemia was reversed by the removal of the drug after exposure to 1 micro M of JAS for 1 day. Electron microscopy revealed that the merozoites treated with JAS showed a protrusion of the apical end which contained the microfilament structure. Immunoblot analysis indicated that the JAS treatment increased F-actin filaments of merozoites but had no effect on those of the trophozoites and schizonts. Therefore, this study demonstrated that JAS has an antimalarial activity.

BackgroundOn 11 March 2011, the Tohoku earthquake and tsunami struck off the coast of northeastern Japan. Within 3 weeks, an increased number of pneumonia admissions and deaths occurred in local hospitals.MethodsA multicentre survey was conducted at three hospitals in Kesennuma City (population 74 000), northern Miyagi Prefecture. All adults aged ≥18 years hospitalised between March 2010 and June 2011 with community-acquired pneumonia were identified using hospital databases and medical records. Segmented regression analyses were used to quantify changes in the incidence of pneumonia.ResultsA total of 550 pneumonia hospitalisations were identified, including 325 during the pre-disaster period and 225 cases during the post-disaster period. The majority (90%) of the post-disaster pneumonia patients were aged ≥65 years, and only eight cases (3.6%) were associated with near-drowning in the tsunami waters. The clinical pattern and causative pathogens were almost identical among the pre-disaster and post-disaster pneumonia patients. A marked increase in the incidence of pneumonia was observed during the 3-month period following the disaster; the weekly incidence rates of pneumonia hospitalisations and pneumonia-associated deaths increased by 5.7 times (95% CI 3.9 to 8.4) and 8.9 times (95% CI 4.4 to 17.8), respectively. The increases were largest among residents in nursing homes followed by those in evacuation shelters.ConclusionsA substantial increase in the pneumonia burden was observed among adults after the Tohoku earthquake and tsunami. Although the exact cause remains unresolved, multiple factors including population aging and stressful living conditions likely contributed to this pneumonia outbreak.