Glossopharyngeal-hypoglossal nerve reflex of the frog in metamorphosis

In adult frogs, a reflex discharge is elicited from the hypoglossal nerve by mechanical and chemical stimuli to the centre of the tongue surface and electrical stimuli to the glossopharyngeal nerve innervating tongue. However, there has been no report concerning the embryological stage at which this reflex develops. The metamorphosis of a frog is divided into three parts, premetamorphic, metamorphic and climax stage. In the climax stage, the forelimbs are lengthened and the tail gradually shortened. The glossopharyngeal-hypoglossal nerve reflex arose in the early climax stage, during which the tongue appeared on the floor of the mouth. At this stage, the conduction velocities of the first compound action potential of the glossopharyngeal and hypoglossal nerves were about 8.7 and 9.3 m/s, respectively. The latency of the reflex was long, especially the central latency. The response of the glossopharyngeal nerve and the reflex discharge from the hypoglossal nerve upon mechanical stimulation of the tongue were smaller in the tadpole than in the adult frog. As metamorphosis proceeded, the conduction velocity of these nerves increased; the latency shortened, especially the central latency; the reflex response to mechanical stimulus increased. These results suggest that, although the glossopharyngeal-hypoglossal nerve reflex is developed in the early climax stage, it is completed only in the adult frog. Therefore, adult frogs living mainly on land may reject and swallow prey by this reflective tongue movement.

Tactile and taste sensory maturation of the frog larvae tongue

The maturation process of organs in the oral cavity of the larvae of bullfrogs, Rana catesbeiana, corresponding to the larval stages XVIII to XXV distinguished by Taylor and Kallros Anat. Rec., 94 (1946) 7-25, were investigated. In this study, these larval stages were divided by the width of the mouth slit into A1, A2, B and C stages. The A1 and A2 stages corresponded to larval stages XVIII-XIX and XX, respectively. The B and C stages corresponded to stages XXI and XXII-XXV, respectively. In stage A1, mechanical and chemical stimulation of the tongue rudiment, in most larvae, failed to elicit afferent discharges in glossopharyngeal nerves. However, in a small number of larvae, obvious afferent discharges of these nerves were generated. In stage A2, glossopharyngeal nerves in most larvae began responding to the same stimulations. The amplitude increased with decreasing duration of afferent discharges, resembling those of the adult. In stage B, the first glossopharyngeal-hypoglossal nerve reflex (G-H reflex) was elicited by mechanical stimulation of the tongue. In stage C, the G-H reflex was also induced by chemical stimulation and the latency of the G-H reflex elicited by mechanical stimulation decreased. In this stage, expansion and extension of the tongue increased. Therefore, the natural function of this reflex for the intake of food may follow this stage.

The evidence for post-meiotic expression of a testis-specific isoform of a regulatory subunit of calcineurin using a monoclonal antibody

The expression of a regulatory subunit of calcineurin (CaN beta) during rat spermatogenesis was examined in rat testes using a monoclonal antibody Va1. Results showed that a testis-specific isoform of CaN beta was expressed only 3 weeks after birth, when meiosis begins, and increased in amount depending on the maturation of spermatogenesis. The matured sperm, which consists of only post-meiotic cells, is most likely to have only the testis-specific isoform of CaN beta. The brain type isoform of CaN beta was not detected in rat sperm. Immunoblot analysis of testes from different rodent species by a monoclonal antibody Va1 showed that all rodent species examined had their own homologues corresponding to a testis-specific isoform of CaN beta in rats, although they showed distinctively different molecular weights on SDS-PAGE compared to the testis-specific isoform in rats. Each homologue was shown to be specifically expressed in post-meiotic phase of spermatogenesis, as was seen in rats.

Glycemic response and fiber content of some foods

The proposed mechanisms for the action of dietary fiber (DF) on the glycemic response suggest a nonlinear relationship between glycemic index (GI) and DF content. This relationship was analyzed by using the newly reported total DF (TDF) values, assuming a nonlinear regression curve. The empirical equation obtained was Y = 19.9X-0.322. Similar regression curves were also obtained for soluble DF (SDF) and insoluble DF (IDF). The two regression curves indicated that the correlation coefficient between observed GI and GI calculated from the IDF regression curve (-0.781) was virtually identical to that for SDF (-0.780), but a given content (eg, 5% vs available carbohydrate) of SDF gave a lower GI (39) than did IDF (48). This stronger dependency of GI on SDF suggests a major function of SDF in the TDF hypoglycemic effect. From the regression curve of GI vs TDF, we propose a supplemental GI to predict the glycemic response to foods with no published GI.

Dislocations and Flux Pinning inYBa 2 Cu 3 O 7-δ

Bulk YBa(2)Cu(3)O(7-delta) superconductors, under certain processing conditions such as melt texturing, exhibit a very high dislocation density of 10(9) to 10(10) per square centimeter. In addition, the density of low-angle grain boundaries in such samples can be significantly increased (to less than 700-nanometer spacing) through a dispersion of submicrometer-sized Y(2)BaCuO(5) inclusions. These defect densities are comparable to those in high critical current thin films as revealed through scanning tunneling microscopy, and yet the critical current densities in the bulk materials (at 77 kelvin and a field of 1 tesla for example) remain at a 10(4) amperes per square centimeter level, about two orders of magnitude lower than in thin films. The results imply that these defect density levels are not significant enough to explain the difference in flux pinning strength between the thin film and bulk materials. The observation of spiral-like growth of the superconductor phase in bulk Y-Ba-Cu-O is also reported.

Determination of total dietary fiber in Japanese foods

Total dietary fiber was determined in Japanese foods by the Prosky-AOAC method. To accomplish the analyses of unsuitable samples, we introduced a few minor modifications to the versions for (i) seaweed and fruits, (ii) cereals, and (iii) fish and meats. These modified methods were used together with the standard method to obtain results with reasonably good relative standard deviation for 231 foods and 21 groups of mixed foods. In this study, dietary fiber was defined so as not to exclude the nondigestible polysaccharide portions of animal foods. A method was proposed which could estimate more accurately the fiber components of animal foods by measuring the "nondigestible protein" of the fiber sample of the fiber sample by the Biuret colorimetric method, instead of the Kjeldahl method, to avoid deducting the values for aminopolysaccharides. In Japanese diets, the amount of fiber obtained from animals foods was less than 5% of the total intake of dietary fiber.

Translocation t(8;16)(p11;p13) in neonatal acute monocytic leukaemia

A recent report demonstrated that t(8;16) (p11;p13) may be linked to acute monocytic leukaemia (AMoL) of differentiated subtype (M5b) with active haemophagocytosis by leukaemic cells. Only two cases of neonatal AMoL with t(8;16) (p11;p13) have been reported; M5b with haemophogocytosis and M5a. We report a case of neonatal AMoL (M5b) with t(8;16)(p11;p13), but haemophagocytosis by the leukaemic cells was not detected.

Manometric and histologic assessment following proctocolectomy and straight enteroanal anastomosis in canines

Serial manometric studies were performed in mongrel dogs before and after total colectomy, mucosal proctectomy and interposed jejunoanal anastomosis without pouch. Fecal continence and body weight gain were clinically satisfactory by 28 weeks after surgery. Even at 28 weeks after the mucosal proctectomy, the mean maximal resting anal sphincter pressure was significantly lower than the preoperative level (p less than 0.001). Neorectal compliance also decreased. The rectoanal inhibitory reflexes were not observed 2 weeks after the mucosal proctectomy but atypical to typical patterns gradually appeared up to 28 weeks following the mucosal proctectomy. Histologic examination showed no injury of anal sphincter muscles. Mild inflammation was found in the neorectal mucosal layer in all animals. Meissner's plexus in rectal muscular cuff was almost completely disrupted. These data suggested that there is certain limitation in restoration of anoneorectal function after mucosal protectomy and enteroanal anastomosis, though with gentle and careful operations.

Comparison of blood flow assessment between laser Doppler velocimetry and the hydrogen gas clearance method in ischemic intestine in dogs

Blood flow of the colon and the ileum was measured before and after intestinal devascularization by laser Doppler velocimetry and the hydrogen gas clearance technique in 10 dogs in order to evaluate the clinical usefulness of laser Doppler velocimetry. The submucosal blood flow of the colon and the ileum measured by the hydrogen gas clearance method was significantly decreased, as was the subserosal blood flow of both sites measured by laser Doppler velocimetry. There was a linear relationship between the flow values using the two methods both in the colon (r = 0.7192, p less than 0.001) and in the ileum (r = 0.7646, p less than 0.001). These data suggested laser Doppler velocimetry may be a useful method to assess the degree of intestinal ischemia because of its noninvasiveness and good correlation with submucosal blood flow by the hydrogen gas clearance technique.

Ileostomy using an interposed ileal segment to function as a 'neocolon'

A new type of ileostomy was constructed in rats using an interposed ileal (I-I) segment functioning as a neocolon. The effects of this operation in these rats were compared with a control group undergoing conventional ileostomy (I). Rats in the I group lost weight throughout follow-up, whereas rats in the I-I group regained weight and were significantly heavier four weeks after surgery. Transit time from the stomach to the stoma was significantly prolonged in the I-I group (187 +/- 29 minutes) when compared with the I group (141 +/- 17 minutes, P less than 0.01). Serum analysis revealed no significant differences in total protein, lipids, electrolytes (Na, Cl, CO2), and osmolarity between the groups. Biliary bile salt concentration, normalized bile flow, and normalized bile acid output in the I-I group were not different from those in unoperated control rats, suggesting unimpaired bile acid metabolism. These data suggest this operative procedure has the beneficial effects of slowing intestinal transit and promoting postoperative recovery without impairing distal ileal function.

[Isolated intraventricular hemorrhage due to a ruptured vertebral artery aneurysm]

A rare case of ruptured aneurysm originating from the vertebral artery, and presenting an isolated clot in the fourth ventricle is reported. The patient underwent surgery via a right lateral suboccipital craniectomy on the third day. As the aneurysm was huge and partially thrombosed, trapping was performed and completed successfully. If isolated intraventricular hematoma was found without obvious parenchymal hemorrhage or subarachnoid clot, the diagnosis of vertebral artery aneurysm should be considered as a possibility in addition to posterior inferior cerebellar artery aneurysm. Complete vertebral angiography is indispensable for the recognition of this condition.

A pathologic study of lumbar disc herniation in the elderly

Twenty-nine fragments from herniated lumbar discs of patients over 60 years of age were studied pathohistologically. For comparison, 109 discs from patients under 59 years of age also were observed. They were classified into seven types according to their composition. In 70% of discs from patients between 60 and 69 and in 80% of discs from patients over 70, the fragments were composed of the anulus fibrosus and the cartilaginous end-plate. The authors concluded that the cartilaginous end-plate had avulsed from the vertebral body and herniated with the anulus fibrosus in these cases. This type of herniation occurs more often than herniation of the nucleus pulposus over 30, and may be most common in elderly patients because of their advanced disc degeneration.

Bile composition after total proctocolectomy with interposed jejunal segment as neorectum

Changes of bile composition in gallbladder bile and serum chemistries were investigated in nine dogs after proctocolectomy and ileoanal anastomosis, using an interposed jejunal segment as a neorectum. A significant decrease in cholic acid and an increase in deoxycholic acid were observed 24 weeks after the operation, although there was no significant change of total bile acid and phospholipids in the bile. Concentration of cholesterol and cholesterol saturation index in bile increased after total proctocolectomy. Although serum triglyceride levels became lower compared with the nontreated control group, concentrations of total protein, serum cholesterol, total lipids, blood sugar, and electrolytes showed no significant difference. This operative procedure apparently did not impair intestinal absorption of bile acid, but did increase the biliary cholesterol saturation index.

Sequential occurrence of immune pancytopenia and de novo DIC in a child with polyclonal immunoblastosis

We report a child with polyclonal immunoblastosis associated with several hematological complications. Pure red cell aplasia (IgG-mediated inhibition of erythropoiesis), immune thrombocytopenia and immune neutropenia with myeloid hypoplasia developed sequentially. In addition, disseminated intravascular coagulation occurred shortly after the administration of prednisolone with rapid shrinkage of hepatosplenomegaly and lymphadenopathy.

[Urinary tract infection associated with urinary calculi. 2. Effects of antibiotics on bacteria within infected stones]

We investigated the effect of antimicrobial agents against bacteria within infected stones. Cefmetazole (CMZ) was found to have equally strong activities against gram-positive and gram-negative bacteria isolated from the stones. In addition, CMZ was excreted in the urine from the affected kidney in high concentrations and was penetrated into the stone to some extent in vitro. However, preoperative administration of CMZ did not so significantly eradicate bacteria within the stones. Stones may function as a sanctuary for organisms and may attenuate the effects of antibiotics against them. Therefore, to treat urinary tract infection associated with urinary calculi, complete extirpation is necessary. In recent years, ultrasonic and other types of stone crushing methods are in wide use. CMZ or other effective antibiotics may become useful for the perioperative management of infected urinary stones.

Mechanism of inhibition of reverse transcriptase by quinone antibiotics. II. Dependence on putative quinone pocket on the enzyme molecule

Inhibition of avian myeloblastosis virus (AMV) reverse transcriptase by natural and synthetic quinones including antibiotics could be accounted for by an oxidation-reduction reaction. The quinones were shown to function as electron acceptors as revealed by the catalytic oxidation of NADH by Clostridium kluyveri diaphorase which was in excellent agreement with enzyme inhibition activity. The kinetics of inhibition of AMV reverse transcriptase by three synthetic quinones with different core structures, i.e., 6-methoxy-5,8-dihydroquinoline-5,8- dione, 5,8-dihydroisoquinoline-5,8-dione and 1,4-naphthoquinone, were studied. These quinones inhibited reverse transcriptase in the same manner as streptonigrin (STN) and were shown to act at a single class of reaction site(s) on the enzyme molecule. In contrast, the quinones with bulky substituents, i.e., 7-(2-nitrophenethylamino)-5,8-dihydroisoquinoline-5,8-dione and 7-methoxy-6-methyl-3-piperidino-5,8-dihydroisoquinoline-5,8-dione, were inactive as inhibitors of reverse transcriptase, whereas they retained competent catalytic activities in the oxidation of NADH by C. kluyveri diaphorase. Based on these observations, the existence of a specific site of interaction on the enzyme molecule, referred to as a quinone pocket, was proposed. The quinone pocket might play a crucial role in the early sequence of events leading to the inhibition of reverse transcriptase by quinones including STN and sakyomicin A (SKM). Access of SKM to a quinone pocket might be restricted due to its bulky structure in the vicinity of the quinone group. This is inferred from unsuccessful inhibition of reverse transcriptase by the quinones with bulky substituents, resulting in much poorer inhibition of reverse transcriptase in spite of more potent electron acceptor activity in the oxidation-reduction system as compared with those of STN.