Correlation between somatosensory evoked potentials and long loop reflexes--basic investigation and its application for multiple sclerosis

Somatosensory evoked potentials (SEPs) and long loop reflexes (LLRs) to the median nerve stimulation were investigated on 25 normal controls and 25 patients with multiple sclerosis (MS). Fifteen normal controls were also subjected to LLR study by the common peroneal nerve stimulation. The mean height were 159 +/- 8.2 cm in normal controls and 160 +/- 8.9 cm in MS, respectively. LLRs were obtained with 100% reproducibility in all cases. Upper limb LLRs were recorded from m. abductor pollicis brevis by trigger stimulation during isotonic contraction of the thumb, while lower limb LLRs were recorded from m. peroneus longus by trigger stimulation during isotonic eversion of the foot. The threshold of LLR was lower than that of short latency reflex (H-wave) with the mean latency of 40.4 +/- 1.5 ms. The height of subjects revealed an obvious positive correlation not only with the latency of LLR but also with N 20 of SEP, whereas central conduction time was not. Furthermore, a significant correlation was present between the latencies of LLR and N 20, showing a twofold gradient of LLR against N20. There was a significantly prolonged latency difference between H-wave and LLR of lower limb as compared with that of upper limb. When the stimulation site was changed from the wrist to the elbow, the latency difference between M-wave and H-wave shortened. This fact, therefore, appears to be against "resonance hypothesis" that LLR is set off according to the intrinsic mechanical oscillation given to the muscle concerned.(ABSTRACT TRUNCATED AT 250 WORDS)     

Distant metastases in differentiated thyroid carcinomas: a clinical and pathologic study

Of 514 patients with differentiated thyroid carcinoma treated between 1970 and 1987, 34 (6.6%) had distant metastases. Twelve patients died of their distant metastases; eight of these patients died within 5 years from the time of initial diagnosis. Death from cancer was most frequent in the seventh decade. The metastases were most often found in the lungs and bones. In the fatal group, pleural, brain, and pericardial metastases were noted. Local recurrences were found only in 24% of these 34 patients. Histologic types of primary thyroid tumors and metastatic tumors were reexamined and classified using our criteria, which were mainly based on the World Health Organization nomenclature and currently obtained pathologic observations of thyroid tumors. In 31 thyroid tumors, the surgical specimens were available for review. Twenty-four tumors were papillary and seven were follicular. Of the 24 papillary carcinomas, nine were follicular, eight were well-differentiated, and seven were trabecular. On the other hand, the seven follicular carcinomas consisted of four well-differentiated, two solid, and one oxyphilic. The majority of the thyroid tumors showed an extrathyroidal extension; however, two were intrathyroidal carcinomas and two were encapsulated carcinomas, larger than 5 cm in diameter. Distant metastases were confirmed morphologically in 18 patients (11 by surgical or biopsy material, five by autopsy, and two by cytology). The histologic types of metastatic tumors were consistent with those of primary thyroid tumors. Diagnostic 131I uptake was examined in 32 patients and absorption of diagnostic 131I in metastatic tumors was demonstrated in 21 patients. The 10-year survival rate of patients with 131I accumulating metastases (70%) was significantly better than that of patients with metastases lacking such uptake (40%). Immunoreactivity for thyroglobulin in metastatic tumors was correlated with the 131I absorption. This finding indicated that immunostaining of thyroglobulin in metastatic tumors might be useful in the prediction of the effectiveness of 131I therapy.     

Occlusion and subsequent re-canalization in early duodenal development of human embryos: integrated organogenesis and histogenesis through a possible epithelial-mesenchymal interaction

Histogenesis of the duodenum, especially changes in the epithelium in relation to temporal occlusion and re-canalization of the lumen, was investigated by light microscopy together with morphometric analysis, as well as by scanning and transmission electron microscopy of 133 externally normal human embryos ranging from Carnegie stage 12 to 23. A series of morphogenetic events passed the duodenum in a cranio-caudal (proximo-distal) wave like fashion during the period examined. They included: (1) a decrease in the caliber and area of the lumen, (2) ’occlusion’ of the lumen, (3) vacuole formation, (4) ’re-canalization’ and villi formation. The only exemption to this rule was that, in the upper part of the duodenum, the lumen was not obliterated in the embryos examined. Morphometric analyses revealed that both the area of the epithelium and the number of epithelial cells decreased during the ’occlusion’ phase. This result suggests that, unlike the classical view, epithelial cell proliferation does not play an important role in occluding the lumen, but the predominant morphogenetic event during this phase is convergence of the epithelial cells to elongate the duodenum. Apoptosis, contrary to some classical views, decreased during the ’re-canalization’ phase, and it appeared to be involved in the formation of the small lumens in the epithelial ’plug’ and in villi formation, but not in enlarging the secondary lumens. The secondary small lumens in the occluded lumen were frequently formed near the border between the central ’plug’ and peripheral basal cells on the basement membrane. This and other findings of concentric differentiation in both the epithelial and mesenchymal layers suggested a possible control mechanism by the epithelium-mesenchymal interaction on human duodenal morphogenesis and histogenesis. The present electron microscopic observations also provided details on the mechanisms involved in the enlargement of the secondary lumen and differentiation of villi. The implications of these findings to duodenal anomalies are also discussed. Accepted: 12 November 2001     

Effect of cordycepin on the replication of western equine encephalitis virus

Summary Cordycepin (3-deoxyadenosine) inhibited viral RNA synthesis in the replication of western equine encephalitis virus, thereby causing a reduction of virus production. The rate of inhibition of viral RNA synthesis was dependent on drug concentration and the period of treatment with the drug. These results suggest that the virus RNA synthesizing system is sensitive to the drug.With 3 Figures     

Maternal and fetal nitric oxide synthesis is decreased in pregnancies with small for gestational age infants

Our purpose was to evaluate whether maternal and fetal nitric oxide synthesis in pregnancies with small for gestational age (SGA) infants are different from those in pregnancies with appropriate for gestational age (AGA) infants. Maternal and fetal circulating nitrate and nitrite concentrations were compared between 30 pregnancies with AGA and 10 pregnancies with SGA at birth. End-products of nitric oxide synthesis were measured in maternal and cord venous blood samples using a fluorometric assay. Umbilical artery blood pH and PO2 were also measured. Maternal circulating nitrite and nitrate concentrations (6.91 +/- 1.27 microM) in pregnancies with SGA were significantly lower than those (11.69 +/- 1.33 microM) in pregnancies with AGA (P = 0.015). Fetal circulating nitrite and nitrate concentrations (7.54 +/- 1.09 microM) in pregnancies with SGA were also significantly lower than those (11.24 +/- 1.08 microM) in pregnancies with AGA (P = 0.024). There were no significant differences in umbilical artery blood pH and PO2 between the two groups. These results suggest that maternal and fetal nitric oxide synthesis are decreased in pregnancies with SGA infants.      

Lipopolysaccharide Induces CD25-Positive, IL-10-Producing Lymphocytes Without Secretion of Proinflammatory Cytokines in the Human Colon: Low MD-2 mRNA Expression in Colonic Macrophages

Despite the huge number of colonized Gram-negative bacteria in the colon, the normal colon maintains its homeostasis without any excessive immune response. To investigate the potential mechanisms involved, human colonic lamina propria mononuclear cells (LPMCs) obtained from uninflamed mucosa were cultured with lipopolysaccharide (LPS) prepared from Bacteroides vulgatus (BV-LPS) or Bacteroides fragilis (BF-LPS), as representatives of indigenous flora, or pathogenic Salmonella minnesota (SM-LPS). Colonic LPMCs failed to produce inflammatory cytokines in response to any type of LPS. Colonic macrophages barely expressed mRNA for MD-2, an essential association molecule for LPS signaling via Toll-like receptor 4. Further, BV-LPS induced CD25 and Foxp3 expression in lymphocytes and CD4(+)CD25(+) cells expressed IL-10 mRNA. Thus, the low expression of functioning LPS receptor molecules and induction of IL-10-producing CD4(+)CD25(+) lymphocytes by indigenous LPS may play a central role in the maintenance of colonic immunological homeostasis.