[The current state of leak in anesthetic machines detected by low flow leak tests]

To assess the current state of leak in anesthetic machines, we selected 66 units of anesthetic machines for inspection and repair from various medical institutions. Based on a newly designed inspection flow chart a low flow leak test for internal circuits of the anesthetic machines was performed. The conventional low flow leak test was also performed for smooth detection of leak for rational evaluation. Only 39% of the anesthetic machines met the standard of the low flow leak tests, and leak was detected in the remaining 61%. The average residual leak mounted to 0.97 l.min-1, with the maximum of 5.3 l.min-1. Canisters, corrugated tubes, and vaporizers were considered the primary causes of leak. After the inspection and repair, leak in 77.5% of the anesthetic machines either disappeared or decreased and the average residual leak dropped to 0.34 l.min-1. However, 47% of the anesthetic machines still failed to meet the standard of the low flow leak tests. To further improve the situation, more detailed inspection and repair are necessary especially for precise detection of the cause of leak in the internal circuit of anesthetic machines which often remains undetected.

Neurogenic vasodilatation of canine isolated small labial arteries

Mechanisms underlying vasodilatation to nerve stimulation by electrical pulses and nicotine were analyzed in isolated canine small labial arteries. Transmural electrical stimulation (5 and 20 Hz) produced a contraction followed by a relaxation in labial arterial strips denuded of the endothelium, partially contracted with prostaglandin F2alpha. The contraction was abolished by prazosin or combined treatment with alpha, beta-methylene ATP. In the treated strips, neurogenic relaxation was abolished by NG-nitro-L-arginine (L-NA), a nitric oxide (NO) synthase inhibitor, and restored by L-arginine. The D-enantiomers were without effect. Nicotine (10(-4) M) also relaxed the arteries, in which the contractile response was abolished by prazosin and alpha, beta-methylene ATP. The relaxant response was attenuated but not abolished by L-NA; the inhibition was reversed by L-arginine. The remaining relaxation by nicotine was abolished by calcitonin gene-related peptide (CGRP)-[8 to 37], a CGRP1 receptor antagonist. Relaxations elicited by a lower concentration of nicotine (2 x 10(-5) M) sufficient to produce similar magnitudes of response to those induced by 5-Hz electrical nerve stimulation were also inhibited partially by L-NA. Histochemical study with the NADPH-diaphorase method demonstrated positively stained nerve fibers and bundles in the arterial wall, suggesting the presence of neuronal NO synthase. It is concluded that the relaxation induced by electrical nerve stimulation of small labial arteries is mediated exclusively by NO synthesized from L-arginine in nerve terminals, whereas nicotine in the concentrations used evokes relaxations by a mediation of nerve-derived NO and also CGRP, possibly from sensory nerves. The reason why nicotine but not electrical pulses stimulates sensory nerves and elicits vasorelaxation remains unsolved.

Apoptosis of villous epithelial cells and follicle-associated epithelial cells in chicken cecum

The process of the disappearance of epithelial cells was examined in chicken cecal villi and follicle-associated epithelium (FAE). The apoptotic epithelial cells with intense DNA-fragmentation and their exfoliation were found in the villous tips. The epithelial cells with weak DNA-fragmentation were seen in the upper portion of the villi and their sparse exfoliations were also found there. Numerous epithelial cells in the intestinal lumen expressed the apoptotic features. A row of apoptotic epithelial cells with DNA-fragmentation was also found in the apical FAE, whereas no M cells exhibited any apoptotic signs. In all cecal regions, CD3+, CD8+, and TCR2+ lymphocytes were predominant in the epithelium at the upper portion of the villi and the FAE. CD4+ lymphocytes were mainly seen in the lamina propria. TCR1+ lymphocytes were not abundant in comparison with TCR2+ lymphocytes in the epithelium. TCR3+ T lymphocytes were rarely detected. These results suggest that the chicken cecal epithelial cells exfoliated into the lumen after the induction of the apoptosis, and that the induction may be involved with CD3+, CD8+, and TCR2+ lymphocytes. No death in M cells suggests that M cells may transform into microvillous epithelial cells.

Cell kinetics of mouse tumour subjected to photodynamic therapy--evaluation by proliferating cell nuclear antigen immunohistochemistry

Tumour reaction and tumour cell kinetics in mouse NR-S1 carcinoma subjected to photodynamic therapy (PDT) were evaluated by percentage of necrotic area as well as by proliferating cell nuclear antigen (PCNA) immunohistochemistry, and an effective PDT fractionation interval was proposed. PDT was carried out in mouse NR-S1 carcinomas using a photosensitizer (haematoporphyrin oligomers: 20 mg kg body weight) and pulsed Nd:YAG dye laser. The percentages of tumour necrotic area and PCNA labelling indices (LIs) in the tumours were assessed at intervals of 0, 0.5, 5, 2.5, 6, 24, 48, and 72 h after PDT. It was demonstrated that maximum damage and repopulation of the tumour cells emerge at 24 and 48 h, respectively, following PDT, suggesting that subsequent light treatment should be performed within 24 h to enhance the therapeutic effect of PDT.

Ultraviolet light is an environmental factor aggravating facial lesions of adult atopic dermatitis

An increasing number of adult patients with atopic dermatitis (AD) in Japan are distressed by persistent eczematous lesions of the face (so-called atopic red face). Phototests were carried out in 28 patients with the atopic red face to test a possibility that ultraviolet (UV) light could be an aggravating factor. Contact and photocontact dermatitis had been ruled out by repeated patch and photopatch tests. All of the patients had a normal response to a screening dose of UVA (10 J/sq cm) and a normal minimal erythema dose (MED) of UVB. Ten of these patients, however, showed an abnormal papular response to a single or 3-times consecutive UVB radiation above the MED (90 mJ/sq cm).

Effects of iron and copper supplementation on the formation of thiobarbituric acid-reactive substances and phosphatidylcholine hydroperoxide in the livers of iron- and copper-deficient rats

Free radicals and lipid peroxide formation are related to tissue damage. This damage is thought to be associated with various diseases. To accurately assess the degree of lipid hydroperoxidation in biological materials, three different thiobarbituric acid (TBA) assay methods and the measurement of phosphatidylcholine hydroperoxide (PCOOH) by the chemiluminescence-HPLC (CL-HPLC) method were compared. Iron and copper deficiencies in rats reduced the contents of these metals. The addition of iron and copper to liver homogenates produced dose-dependent increases and decreases in TBARS, respectively. TBARS measured by the Shinnhuber method slightly increased with the addition of copper. The measurement of PCOOH was less affected by the addition of these metals. TBARS did not reflect lipid peroxidation when different concentrations of metals were present in the samples. The TBARS level is thus not a suitable marker for the assess of lipid peroxidation. PCOOH, accumulated as a primary peroxidation product from membrane phospholipids in the liver, was found to be a more appropriate marker for the estimating hepatic lipid peroxidation in the iron- and/or copper-deficient condition.

Developmental study on reduction and kinks of the tail in a new mutant knotty-tail mouse

The knotty-tail (knt/knt) mouse has a short and knotty tail. The tail deformity is caused by a decrease in the number of caudal vertebrae and a deformity of them in the distal part of the tail. The objective of the study was to determine how reduction and kinks of the tail region were formed during secondary body formation. By day 12.0 pc, the somitogenesis of knt/knt embryos was completed; the number of caudal somites more or less agreed with those of the caudal vertebrae in knt/knt mice and were similar to those of knt/+ embryos. On the other hand, the somitogenesis of knt/+ embryos continued up to day 12.5 pc. The somites below about the sixth caudal somite were wedge-shaped with a dorsal apex in knt/knt embryos. The location of abnormal somites also corresponded well to that of deformed caudal vertebrae. Abnormal somitogenesis was always preceded by abnormalities in the presomitic region. Under gross observation, this could be seen to become markedly thickened, and histologically its dorsoventral diameter increased in the transverse plane on days 10.5-12.0 pc. In the mesenchyme there was often obvious cell death at the boundary of the unsegmented area and the tail bud after day 10.5 pc. These results suggested that the shortness of tail was primarily caused by the agenesis of distal caudal vertebrae following the agenesis of distal caudal somites, and partly by the disappearance of the presomitic part due to cell death, while the tail kinks were caused by the deformation of each caudal vertebra following disturbances of the caudal somites. Also, it is highly probable that the prominent cell death at the boundary of the unsegmented area and the tail bud may involve a defect or deformity of somites in this mutant.

Proliferation and cellular kinetics of villous epithelial cells and M cells in the chicken caecum

The proliferation sites and cellular kinetics of villous epithelial cells and M cells in the intestine of the adult chicken have never been clarified. In this study, we determined the proliferation sites in the chicken caecum using colchicine treatment and detection of proliferative cell nuclear antigen (PCNA). The cellular kinetics of these cells were also studied using bromodeoxyuridine (BrdU) as a tracer. Enterocytes in their mitotic period were observed along the entire length of the intestinal crypt of the caecum, with a denser distribution in the middle portion of the crypt, except for the caecal tonsil. The centres of distributions were at 49% of the distance from the bottom of the crypt in the base and 41% in the apex of the caecum. In the caecal tonsil, the centres of distributions were at 64% in the long type of crypt from the bottom of the crypt and at 44% in the short type of crypt. On the other hand, the PCNA-positive enterocytes were distributed more densely at the bottom of the crypt, except for the caecal tonsil. The centres of distributions were at 36% in the base from the bottom of the crypt, 37% in the body, and 34% in the apex. In the caecal tonsil, they were at 54% in the long type of crypt and 44% in the short type. The BrdU-labelled enterocytes reached to the basement of the intestinal villi in all caecal portions at 1 d after the BrdU administration. The leading edge of the labelled enterocytes disappeared from the villous tips at 4 d in the base and the body and 3 d in the apex. In the caecal tonsil, the BrdU-labelled microvillous epithelial cells and the M cells appeared near the orifice of the crypt at 1 d, and BrdU-labelled M cells were not observed in the crypt. Thereafter, almost all of these cells disappeared at 5 d from the follicle associated epithelium (FAE). These results suggest that M cells are transformed from their precursors within 1 d, and the turnover time for M cells occurs within 4 d after the cell division of the precursors.

Diminished kidney function and nephrocalcinosis in rats fed a magnesium-deficient diet

The effect of a magnesium-deficient diet on kidney function was studied in young male rats. The rats were fed a purified diet with a magnesium content of either 20.5 (control diet) or 2.6 mmol/kg (magnesium-deficient diet) for 21 d. In rats fed the magnesium-deficient diet, kidney wet and dry weights were significantly increased, and calcium and phosphorus concentrations in the kidney were significantly higher than in rats fed the control diet. Upon histological examination, an increase in the mesangial matrix of the glomeruli and injury to the brush border of the proximal tubules were observed in rats fed the magnesium-deficient diet. Also, a deposition of calcium was observed in the tubules of the corticomedullary junction and medulla of these rats. Total protein and albumin concentrations in serum were significantly decreased in rats fed the magnesium-deficient diet. Urinary albumin excretion was significantly higher, and N-acetyl-beta-D-glucosaminidase activity in the urine was significantly increased in rats fed the magnesium-deficient diet. These findings indicate diminished glomerular and proximal tubular functions. We suggest that a magnesium-deficient diet not only induces nephrocalcinosis, but it also diminishes kidney function.

Prevalence of childhood and adolescent atopic dermatitis in a Japanese population: comparison with the disease frequency examined 20 years ago

To ascertain the prevalence of childhood and adolescent atopic dermatitis in a Japanese population, we clinically observed the total body of 5 to 6-year-old children (994 cases), 7 to 9-year-old children (1,240 cases), 10 to 12-year-old children (1,152 cases), 13 to 15-year-old children (1,670 cases), and 16 to 18-year-old adolescents (2,159 cases). The examination was performed in the spring of 1994-96, when exacerbation of childhood and adolescent atopic dermatitis most frequently occurs in Japan. Atopic dermatitis was observed in 24% of the 5 to 6-year group, in 19% of the 7 to 9-year group, in 15% of the 10 to 12-year group, in 14% of the 13 to 15-year group, and in 11% of the 16 to 18-year group. The prevalence of atopic dermatitis in 9 to 12-year-old children was two times and in 18-year-old adolescents five times as high as in similar age groups examined 20 years ago.

[Declarations by registered nurses from the 1980s: an aid to the understanding of nursing today]

This study is part of a more extensive project that aims to rescue significant aspects related to the evolution of nursing care from 1950s until 1990s. This study was developed using the technique of oral declaration by active and retired registered nurses, in the context of a school-hospital from the interior of the São Paulo State. The present study particularizes the outcomes regarding to 1980s. As result becomes evident the undertaken effort by nurses in the struggle for profession's recognition and prestige; intense and deep transformations related to nurse's new roles as leadership of the nursing staff and members of the medical team.

The anti-tumor effect of photodynamic therapy evaluated by bromodeoxyuridine immunohistochemistry

The anti-tumor effect of photodynamic therapy (PDT) on mouse tumors was evaluated with bromodeoxyuridine (BrdU) immunohistochemistry. BrdU was injected into the mice intraperitoneally (40 mg/kg body weight). Immediately after injection of BrdU, PDT using a photosensitizing drug (hematoporphyrin oligomers: 20 mg/kg body weight) was carried out on the experimental group but not on the control group. BrdU labeling indices (LIs) of the tumor cells close to blood vessels and adjacent to the surrounding normal tissue were investigated. In the tumor cells close to blood vessels, the LIs of the experimental group were significantly lower than those of the control group. As for the tumor cells adjacent to the surrounding normal tissue, the LIs of the experimental group were similar to those of the control group. Thus, the effect of PDT was significant in the tumor cells close to the blood vessels, while the tumor cells adjacent to the surrounding normal tissue resisted PDT.

Quantitative studies of nuclear bodies in astrocytes of chicken spinal cord following axotomy

The present study was designed to reveal whether astrocytic activation following axotomy causes a numerical increase of nuclear bodies (NBs) in chicken astrocytes. Astrocytes in the spinal cord were activated by a unilateral spinal nerve transection. The frequency of NBs was calculated at the lateral motor columns of the normal group and at the ipsi- and contralateral sides of operated group. In the growing chickens, NBs of each astrocyte were a few and decreased steadily in number with age. In the operated chickens, the frequency of NBs elevated temporarily both in the ipsi- and contralateral sides, and reached its maximum value by 30 post-operative days. The frequency of NBs increased more prominently in the operated side than in the unoperated side. Thus, the present study provides the first evidence for a significant increase in the number of NBs in the hyperactive astrocytes caused by axotomy.

Cyclic adenosine monophosphate phosphodiesterase activity in peripheral blood mononuclear leucocytes from patients with atopic dermatitis: correlation with respiratory atopy

We determined the cyclic adenosine monophosphate phosphodiesterase (cAMP-PDE) activity in peripheral blood mononuclear leucocytes from 100 patients with atopic dermatitis (AD) aged 13-57 years (mean +/- SD, 29.8 +/- 17.7 years). The correlation between cAMP-PDE activity and clinical parameters such as the severity of eczema and a personal or family predisposition to atopic respiratory diseases (ARD) (asthma or allergic rhinitis) was examined. Although the enzymic activity varied from normal to very high in the AD patients, cAMP-PDE activity was significantly (P < 0.005) elevated in AD patients (42.1 +/- 22.0 units) as compared with the normal controls (12.4 +/- 5.6) and clinical control subjects (13.4 +/- 9.5). In contrast, we found no correlation between cAMP-PDE activity and the severity of eczema when AD patients were classified into four categories (remission, mild, moderate and severe) according to the extent of their skin involvement. Furthermore, we found that systemic corticosteroid therapy in severe AD patients did not alter the cAMP-PDE activity. cAMP-PDE activity was significantly (P < 0.01) higher in those AD patients who had a personal history of ARD (47.2 +/- 11.2) than in AD patients with a family history of ARD (37.2 +/- 17.4) and those without a personal or family history ('pure' AD) (34.4 +/- 19.8). Nevertheless, the cAMP-PDE activity was significantly higher even in 'pure' AD patients than in the controls. These results suggest that an elevation of cAMP-PDE activity is closely related to a predisposition to respiratory atopy, and does not follow inflammation in AD patients.

Comparison of bromodeoxyuridine labeling indices of smears and sections from mouse NR-S1 tumor

Bromodeoxyuridine (BrdU) labeling indices (LIs) of smears and sections from mouse NR-S1 tumor were labeled in vivo or in vitro and compared to confirm the reliability of smears labeled in vitro. In vivo labeling was carried out by administering 40 mg/kg 5-bromo-2'-deoxyuridine while in vitro labeling was performed by incubating the tumor specimens in RPMI 1640 culture medium containing 200 microM 5-bromo-2'-deoxyuridine under 3 atmospheres. BrdU LIs of sections labeled in vitro (9.49 +/- 0.16) showed lower values than those labeled in vivo (14.95 +/- 0.36). BrdU LIs of smears labeled in vitro (9.87 +/- 0.23) also showed lower values than those labeled in vivo (14.83 +/- 0.49). However, the BrdU LIs of smears were similar to those of sections labeled in vivo and in vitro. In vitro BrdU immunochemistry in smears seems useful for evaluating the biological properties of tumor tissues.

Occlusive effects of lactic acid-glycolic acid copolymer membrane on gingival fibroblasts in vitro

The cell occlusive effects on human gingival fibroblasts of degradable lactic acid-glycolic acid copolymer membranes (noncoated membranes) and membranes coated with a sucrose ester of fatty acid (coated membranes) were studied and compared with those of expanded polytetrafluoroethylene (e-PTFE) membranes. The membranes were immersed in a culture medium periodically for 21 days and interposed into a chemotaxis chamber, and the fibroblasts then were cultured in the chamber for another 7 days. The passage rate of cells through the membranes was calculated and the change in surface structure of each membrane after immersion for 28 days was observed by an environmental scanning electron microscope. The passage rate of coated membranes (3.4+/-2.2%) was significantly lower than that of noncoated (25.7+/-5.1%) at the 28th day whereas the passage rate of e-PTFE membranes was 0.8-1.5%. Many pores were observed on the noncoated membranes before immersion while the coating material covered most of the pores on the coated membranes. The average pore size of the noncoated membranes was larger than that of the coated membranes at day 28. The structure of the e-PTFE membranes underwent no change. The passage rate of the coated membranes was not different from the e-PTFE membranes, suggesting an effect that might be useful for a guided tissue regeneration procedure.

Bradykinin potentiates insulin-stimulated glucose uptake and enhances insulin signal through the bradykinin B2 receptor in dog skeletal muscle and rat L6 myoblasts

Previously we demonstrated that bradykinin infusion could increase glucose uptake into dog peripheral tissues, and that bradykinin could potentiate insulin-induced glucose uptake through glucose transporter 4 (GLUT4) translocation in dog adipocytes. However, skeletal muscle is the predominant tissue for insulin-mediated glucose disposal. The aim of this study was to determine how bradykinin affected insulin-stimulated glucose uptake in dog skeletal muscle and myotubes transformed from rat L6 myoblasts. The bradykinin receptor binding studies revealed that dog skeletal muscle and rat L6 myoblasts possessed significant numbers of bradykinin receptors (Kd = 88 and 76 pmol/l, Bmax = 82.5 and 20 fmol/mg protein respectively). An RT-PCR (reverse transcriptase-polymerase chain reaction) amplification showed mRNA specific for bradykinin B2 receptor in both cells. Bradykinin significantly increased 2-deoxyglucose uptake in isolated muscle and L6 myoblasts in the presence of insulin (10(-7) mol/l) in a dose-dependent manner, but not in the absence of insulin. Bradykinin also enhanced insulin-stimulated GLUT4 translocation, and insulin-induced phosphorylation of insulin receptor beta subunit and insulin receptor substrate-1 (IRS-1) without affecting the binding affinities or numbers of cell surface insulin receptors in both cells. It is concluded that bradykinin could potentiate the insulin-induced glucose uptake through GLUT4 translocation in dog skeletal muscle and rat L6 myoblasts. This effect could be explained by the potency of bradykinin to upregulate the insulin receptor tyrosine kinase activity which stimulates phosphorylation of IRS-1, followed by an increase in GLUT4 translocation.

Dietary fructooligosaccharides prevent postgastrectomy anemia and osteopenia in rats

Gastrectomized rats develop anemia and osteopenia, and ingestion of fructooligosaccharides leads to an increase in iron absorption and promotes recovery from anemia in iron-deficient rats. Laparotomized (sham-operated control) rats and totally gastrectomized (Billoth II) rats, in groups of 14 each, were fed a control diet without fructooligosaccharides or a diet containing fructooligosaccharides (75 g/kg of diet) for 6 wk. All rats received an intramuscular injection of vitamin B-12 every 2 wk. Tail blood was collected every week for determination of hematocrit and hemoglobin concentration. At the end of the experiment, the rats were killed and the femur and tibia were collected for measurement of bone mineral density (BMD). The hematocrit, hemoglobin concentration, hemoglobin regeneration efficiency, and BMD of both femurs and tibias were significantly lower in gastrectomized rats fed the control diet than in the other three groups. Dietary fructooligosaccharides prevented anemia and osteopenia in totally gastrectomized rats.

Accidental transmission of HCV and treatment with interferon

Accidental transmission of contagious pathogens, especially hepatitis C virus (HCV), by needlestick or other means as an occupational hazard for medical staff is of concern. We retrospectively analysed cases of work-related accidental injury with pathogens such as hepatitis B virus (HBV), HCV, syphilis and human immunodeficiency virus (HIV) reported to the centres for disease control at 15 hospitals (total 5776 beds) in the Gunma prefecture, Japan, from December 1990 to August 1993 (24.7 months). There were 416 such cases (16.8 cases/month), with an incidence of 0.2-3.5 accidents per month per hospital. Such accidents occurred in 297 (71.2%) nurses, 98 (23.5%) medical doctors, 13 (3%) laboratory technicians, four (1.0%) hospital maintenance workers, one (0.2%) assistant nurse, one secretary and two others. There were 323 (77.6%) injuries caused by needlestick, 42 (10.1%) from suture needles or surgical knife cuts, 17 (4.1%) from blood splatters from patients into the eyes or mouth, 10 (2.4%) from contact with injured skin and 24 (5.8%) simple skin contacts. Of the pathogens, 60.3% were HCV, 22.6% HBV, 5.8% syphilis, 0.7% HIV and 10.6% were of unknown origin. Four cases (1.6%) of HCV infection were found and treated with one or two courses of interferon therapy, and HCV was subsequently cleared. All four patients were cured with interferon therapy. None of the HBV-injured cases resulted in infection, possibly because of prophylaxis with HB immunoglobulin and HB vaccine. No HIV or syphilis infection was contracted. In summary, chronic HCV infection acquired as an occupational hazard can be cured by appropriate treatment, such as with interferon, after early detection of the infection.

Distribution of lymphoid tissue in the caecal mucosa of chickens

In order to clarify the fundamental structure of the host defence mechanism in chicken caeca, a detailed analysis of the distribution of lymphoid nodules (LNs) was carried out on longitudinal sections of both the mesenteric (side of the ileocaecal ligament) and the antimesenteric mucosa. An overwhelming majority of solitary or aggregated LNs were located in the mesenteric mucosa, although a few were also found in the antimesenteric mucosa. Of the total LNs, 45.7% were detected at the proximal 7.8% section in the caecal tonsil. LNs (21.4%) were also concentrated in the distal 22.0% section corresponding to the apex. A moderate concentration of LNs (13.1%) was found at the transitional 20.0% region between the base and body. Approximately 80.2% of total LNs were found at the above 3 regions in the mesenteric mucosa. In many cases, the frequency of LNs in the caecal tonsils was opposite to that at the apices. Aggregated LNs were mainly found in the caecal tonsils, transitional region and apex. Almost all aggregated LNs consisted of fundamental nodular units possessing M cells in their follicle associated epithelia. The aggregated LNs in the above 3 regions therefore could provide immunological surveillance against caecal luminal contents. In particular, the cooperative function between LNs of the caecal tonsil and apex might be highly important in maintaining the caecal microenvironment.