Elevated membrane IgA+ and CD4+ (T helper) populations in murine Peyer's patch and splenic lymphocytes during dietary administration of the trichothecene vomitoxin (deoxynivalenol)

Recent investigations indicate that dietary exposure to the trichothecene vomitoxin increases total and antigen-specific serum immunoglobulin A (IgA) and glomerular IgA accumulation in mice. In this study, the effects of 25 ppm dietary vomitoxin on the histological and lymphocytic profile of component immune organs in the mucosal lymphocyte migratory pathway were evaluated in the B6C3F1 mouse. Vomitoxin administration resulted in marked stimulation of the size and frequency of germinal centres in Peyer's patches, mesenteric lymph nodes and the spleen. A slight increase in the percentage of B cells in the Peyer's patch was observed, although vomitoxin treatment had no effect on the percentage of B cells in the spleen. The percentage of IgA+ cells in Peyer's patches and spleen were approximately twice that of controls at 4, 8 and 12 wk of vomitoxin exposure whereas the percentage of IgG+ cells decreased in these two organs. Exposure to vomitoxin increased the percentage of T cells in Peyer's patches and the spleen. The percentage of CD4+ cells (T helper subset) increased slightly in Peyer's patches and more markedly (30-50%) in the spleen following vomitoxin treatment. Contrastingly, there was only a slight increase in the percentage of CD8+ cells (T cytotoxic/suppressor subset) in the spleens of vomitoxin-treated mice in comparison with controls, and no effect in Peyer's patches. The relative effects of vomitoxin on these two T cells populations was also reflected in increased CD4+: CD8+ ratios in Peyer's patches and spleen. These results are consistent with the hypothesis that dietary vomitoxin modulates normal regulation of the IgA response at the Peyer's patch level and that this is manifested in an altered lymphocyte distribution pattern in both the mucosal and systemic compartment. Notably increased levels of IgA+ and CD4+ cells are indicative of IgA-producing progenitors and T helper subsets, respectively, that in tandem could favour IgA hyperproduction and elevated IgA in serum.

Identification and function of brain stem neurons regulating rat ileal water absorption

The central nervous system (CNS) regions regulating ileal water and ion absorption are unknown. We determined 1) the CNS origin of brain stem neurons that directly innervate the rat ileum, and 2) that these neurons influence intestinal water absorption. Horseradish peroxidase (HRP) was injected into the muscle layer of the rat ileum. The brains were examined for HRP reaction product (HRPRP) 3, 5, or 7 days later. Only cell bodies of the dorsal motor nucleus of the vagus (DMNV) were labeled. Unilateral cervical vagotomy prevented deposition in the ipsilateral DMNV. To determine whether the DMNV regulates ileal water absorption, electrical and chemical stimulation (30 microA, 4 Hz, 0.2 ms, and 300 pmol L-glutamate every 5 min, respectively) were used. Both the DMNV and the adjacent nucleus tractus solitarius (NTS) were stimulated, causing a reduction in water absorption. Bilateral vagotomy prevented the effect of bilateral electrical stimulation, but unilateral vagotomy did not prevent the decrease due to ipsilateral stimulation. These studies show that 1) the DMNV innervates the ileum, and 2) alteration of vagal efferent activity by stimulation of the DMNV and NTS reduces ileal water absorption.

[Cytological features of small cell lung cancer--relation between nuclear chromatin change and chemotherapeutic effect]

This paper describes the relation between the cytologic features, change of chromatin and effect of chemotherapy in 75 cases of small cell lung cancer. Basing on the microscopic changes of the chromatin in the cancer cells, 4 types were observed: (1) chromatin evenly distributed with fine granules (2) chromatin evenly distributed with rough granules (3) chromatin sparsely distributed with rough granules (4) ink spot-like nuclei. Type 1 was found in 75.7% of the responders to chemotherapy while Type 3 was frequently observed in 69.2% of the non-responders. The results suggest that the changes of nuclear chromatin be used as an index to predict the response to chemotherapy, conforming to Takeshi's observation. Yet, in this series, the exfoliative cells were obtained from the sputum rather than Takeshi's brush during bronchoscopy. The authors believe that the changes of chromatin may be observed clearly if the sputum is fresh, smeared promptly and stained in the standard way.

ATPase activity of erythrocyte membrane in patients with trisomy 21 (Down's syndrome)

ATPase activity of crythroyte membranes was determined in 25 cases of Down's syndrome verified by cytological and psychological examinations. The age range of the patients was 8-25 years; 16 males and 9 females. Thirty health male volunteers were selected as the control group. There was a marked reduction of total ATPase, Na+, K+-ATPase, Mg++ATPase activities and rate of ouabain inhibition in the patients with Down's syndrome. The authors suggest that there might exist transport defects in the red cell membranes in such patients.