Effects of lumbar skin warming on gastric motility and blood pressure in humans

We examined the possibility that lumbar skin warming can increase gastrointestinal motility by investigating the electrogastrogram (EGG), blood pressure, and heart rate with psychometric ratings in healthy humans. Scores of mood state profiles showed that lumbar skin warming (42 degrees C, 20 min) decreased tension-anxiety, depression, anger-hostility, fatigue, and confusion of the participants. A multiple bandpass filter analysis of EGGs showed that a postural transition from orthostatic to supine for measurement caused an increase in dominant frequency of 25-29% towards the frequencies of the normal interdigestive migrating motor complex (IMC). The spectral power of the IMC band, 2.55-3.05 cycles/min, was increased by 20 min-warming, reflecting the increase in gastric contractility. No increase in the spectral power was observed in the time-matched control group without skin warming. Therefore, an increase in contractility is a characteristic of lumbar skin warming. The systolic blood pressure increased by 15% during warm stimulation. Interbeat intervals were not influenced by warm stimulation. An analysis of interbeat intervals by a fast Fourier transform method showed that the cardiac sympathetic and parasympathetic nerves did not play a major role in raising the blood pressure. Vasoconstriction of the mesenteric artery was therefore considered to cause a blood pressure increase during warming. It is hypothesized that vasoconstriction of the visceral arteries by lumbar skin warming increases the blood pressure and gastrointestinal contractility.     

Clinical application of rapid assay of interleukin-6 in influenza-associated encephalopathy

The characteristics of influenza-associated encephalopathy is the high mortality and nimble progress with coma which appears in general cases within 48 hours. Most of patients show no abnormalities in the standard blood checks on admission or in early stage. In this study we investigated if a rapid assay of interleukin (IL)-6 is useful in influenza-associated encephalopathy in early stages. The levels of IL-6 in patients with influenza-associated encephalopathy did not show any significant difference compared with those in patients with febrile convulsion and rotavirus-associated convulsion. However the levels of IL-6 in severe cases were significantly higher than those of mild cases with influenza-associated encephalopathy. Consequently the rapid assay of serum IL-6 is useful to evaluate and decide the therapies.     

αN-catenin expression in the normal and regenerating chick sciatic nerve

Summary The Ca²⁺-dependent intercellular adhesion molecule cadherin is known to be linked to the cytoskeleton by the protein catenin, an association of which appears to be important for the cell-adhesion function of cadherin. Catenin consists of three subtypes-, , and . In our previous study, N-cadherin was shown to be localized on the plasmalemma of normal and regenerating chick peripheral nerve. Thus, as N-catenin is a subtype of -catenin (which is specifically associated with N-cadherin), we investigated the immunolocalization of N-catenin in normal and regenerating chick sciatic nerve. In normal nerve, unmyelinated axons exhibited either intense or weak N-catenin immunoreactivity throughout the axoplasm, whereas myelinated axons were completely immunonegative. Regenerating axons, including those derived from parent myelinated axons, showed N-catenin immunoreactivity of variable intensities in growth cones and axon shafts. Schwann cells were invariably devoid of immunoreactivity. Thus N-catenin is not necessarily bound to the surface plasmalemma, but is distributed throughout the cytoplasm, suggesting that most N-catenin molecules are dissociated from N-cadherin.     

Nondestructive evaluation of blood flow in a dialyzer using X-ray computed tomography

It is very important to observe the concentrations and flow patterns of blood through a dialyzer to evaluate its function and to obtain the most appropriate design. We established a visualization method for the blood flow pattern in a dialyzer using X-ray computed tomography, and investigated the so-called internal filtration phenomenon. The results obtained were as follows: (1) The influence of 5% BaSO₄, which was added to the blood as a contrast medium, on the filtration rate of the dialyzer was minimal. (2) The relationship between the concentration of BaSO₄ and the Hounsfield unit value was expressed by linear regression. (3) Hounsfield unit values increased massively just after blood entered the dialyzer and peak values increased with dialysate perfusion under the following conditions: the dialyzer (BS-1.6UL, polysulfone hollow fibers) was used, and bovine blood with 5% BaSO₄ added was used at a blood flow rate of 200ml/min. The dialysate flow rate was 500ml/min and the slice thickness of X-ray computed tomography was 1–10mm. (4) It was observed that blood flowed slightly faster in the center than the peripheral portion of the dialyzer, when the flow pattern was followed after pulse injection of blood containing 20% BaSO₄ into the dialyzer. It was concluded that this method could possibly be utilized not only qualitatively but also quantitatively for observation of the real state of blood flow and in designing dialyzers.     

Depression of the generation of cell-mediated cytotoxicity by suppressor cells after surgery

The effects of surgical operation on the generation of cell-mediated cytotoxicity in mixed cell cultures were studied in patients with various carcinomas or benign lesions. Peripheral blood mononuclear cells from patients were cultured with B lymphoblastoid cell line Raji in mixed culture, and the induced cytotoxicity was measured by 51Cr release assay. In 15 patients with various carcinomas, the capacity of cells to generate cytotoxic cells was significantly depressed 1, 3 and 6 days after surgery, as compared to that before surgery. It returned to the pre-operative level by the 8th post-operative day. In eight patients with benign lesions, significant decrease in cytotoxic cell activity was observed 3 and 6 days after operation. At the 8th day, however, there was a significant increase in the generated cytotoxicity. The depressed generation of cytotoxic cells 3 days after surgery could be abrogated by removal of adherent cells from the responding cell population. This effect could be partially reconstituted by addition of separated, autologous adherent cells back to the responding non-adherent cell culture. These results demonstrate that suppressor cells, presumably monocytes, may be responsible for the depressed generation of cytotoxic cells after surgery.     

Studies on Acute Methionine Toxicity: I. Nucleolar Disaggregation in Guinea Pig Hepatic Cells with Methionine or Ethionine and Its Reversal with Adenine

The effects of methionine and ethionine on the fine structure of hepatic cell nucleoli of guinea pigs and rats were investigated. A single intraperitoneal injection of methionine into guinea pigs results in the disruption of nucleolonema as early as 2 hours after the injection. By 4 hours, nucleoli show complete fragmentation consisting of many small fragments and small remnants of nucleoli. Large aggregates of interchromatinic granules and condensation of chromatin appear in the nucleoplasm. These changes are remarkably similar to the lesions induced by ethionine in the liver of the rat or the guinea pig. The methionine-induced nuclear and nucleolar lesions persist up to 10 hours after the injection. The administration of adenine 4 hours after the methionine injection reverses the nucleolar lesions by 8 hours. The appearance of incompletely reconstructed nucleoli with twisted ropelike structures suggests a pattern of recovery very similar to the adenine-induced nucleolar reformation in ethionine-treated rats. Injecting methionine into rats induced no nucleolar abnormalities. It is suggested that the mechanism of nucleolar fragmentation induced by methionine or ethionine is related to the accumulation of S-adenosyl compounds with concomitant ATP deficiency in the liver.     

Relationship between immediate hypersensitive reactions by buckwheat ingestion and specific IgE for rice in subject with positive IgE-RAST for buckwheat]

IgE-mediated mechanisms are important in immediate hypersensitive reactions (IHR) to buckwheat. However, a part of subjects with high IgE for buckwheat show no IHR to buckwheat ingestion. Inspite of cross-allergenicity between buckwheat and rice, rice ingestion rarely induces IHR even in subjects with high IgE for rice unlike buckwheat-induced IHR. We speculated that there were some relationships between the presence of IHR to buckwheat and recognition of cross-allergenic determinants on buckwheat components with rice components. We examined IgE-RAST for rice in 58 subjects with positive IgE-RAST for buckwheat. IgE-RAST for Dermatophagoides pteronyssinus (Dp), egg white and cow's milk as unrelated antigens with rice were also assessed for a comparison. Subjects (n = 33) without IHR to buckwheat showed higher IgE-RAST values for rice than those (n = 25) with IHR, whereas there were no differences in IgE-RAST values for Dp, egg white and cow's milk between two groups with and without IHR. IgE-RAST values for buckwheat showed significant close correlations to those for rice in subjects without IHR to buckwheat but not in those with IHR. There were no significant correlations between IgE-RAST values for buckwheat and for Dp, egg white or cow's milk in both groups with and without IHR. These results suggested that the IgE from subjects without IHR to buckwheat recognized cross-allergenic determinants with rice on the buckwheat components.     

Dual-probe assay for rapid detection of drug-resistant Mycobacterium tuberculosis by real-time PCR

Mutations in particular nucleotides of genes coding for drug targets or drug-converting enzymes lead to drug resistance in Mycobacterium tuberculosis. For rapid detection of drug-resistant M. tuberculosis in clinical specimens, a simple and applicable method is needed. Eight TaqMan minor groove binder (MGB) probes, which discriminate one-base mismatches, were designed (dual-probe assay with four reaction tubes). The target of six MGB probes was the rpoB gene, which is involved in rifampin resistance; five probes were designed to detect for mutation sites within an 81-bp hot spot of the rpoB gene, and one probe was designed as a tuberculosis (TB) control outside the rpoB gene hot-spot. We also designed probes to examine codon 315 of katG and codon 306 of embB for mutations associated with resistance to isoniazid and ethambutol, respectively. Our system was M. tuberculosis complex specific, because neither nontuberculous mycobacteria nor bacteria other than mycobacteria reacted with the system. Detection limits in direct and preamplified analyses were 250 and 10 fg of genomic DNA, respectively. The system could detect mutations of the rpoB, katG, and embB genes in DNAs extracted from 45 laboratory strains and from sputum samples of 27 patients with pulmonary TB. This system was much faster (3 h from DNA preparation) than conventional drug susceptibility testing (3 weeks). Results from the dual-MGB-probe assay were consistent with DNA sequencing. Because the dual-probe assay system is simple, rapid, and accurate, it can be applied to detect drug-resistant M. tuberculosis in clinical laboratories.     

Accelerated Loss of Islet β Cells in Sucrose-Fed Goto-Kakizaki Rats, a Genetic Model of Non-Insulin-Dependent Diabetes Mellitus

The Goto-Kakizaki (GK) rat is a spontaneously diabetic animal model of non-insulin-dependent diabetes mellitus, which is characterized by progressive loss of β cells in the pancreatic islets with fibrosis. In the present study, we examined the effects of sucrose feeding on the islet pathology in this model. Six-week-old GK rats were fed with 30% sucrose for 6 weeks to induce severe hyperglycemia, and their condition was compared with that of nontreated rats. Age-matched normal Wistar rats were also given sucrose for the same periods and used for comparison. The sucrose-treated GK rats showed elevated blood glucose levels on oral glucose tolerance tests at 60 minutes and 120 minutes, representing 123% and 127% of values in untreated GK rats, respectively. At the end of the study, the mean β-cell volume density in GK rats was 50% less than that in untreated Wistar rats. Sucrose feeding further reduced the volume densities of β cells to only 50% of the levels of age-matched GK rats. Apoptotic cells were found in islet β cells only in GK rats fed sucrose (mean 0.067%). There appeared to be more islets that immunohistochemically stained strongly positive with 8-hydroxy-deoxyguanosine as a marker of oxidative damage of DNA in GK rats fed sucrose compared with those not given sucrose. GK rats not fed sucrose showed significantly lower proliferative activity of β cells measured by 5-bromo-2′-deoxyuridine uptake and intensified expression of Bcl-2 immunoreactivities at 6 weeks of age compared with those in age-matched Wistar rats. These two indices were reduced in both GK and Wistar rats with increasing age and were not affected by sucrose feeding in either group. The present study thus indicated that sucrose feeding promoted the apoptosis of β cells in GK rats through increased oxidative stress without altering their proliferative activity.