Long-term outcome of coronary abnormalities in patients after Kawasaki disease

From January 1973 through December 1992, a total of 302 patients (183 males, 119 females) with Kawasaki disease (KD) underwent coronary angiography. The age at onset of KD ranged from 2 months to 12.3 years (median 1.4 years). The age at the first angiographic evaluation ranged from 6 months to 17 years (median 3.5 years). Most of the patients (85%) had suffered from KD before 1985 and thus were treated without benefit of gamma-globulin. Follow-up varied from 6 months to 25.8 years (median 13.6 years). Coronary abnormalities were confirmed in 71 (23.5%) of 302 patients; the left coronary artery (LCA) alone was involved in 36 cases, the right coronary artery (RCA) alone in 10 cases, and both arteries in 25 cases. Serial angiographic evaluation of the 42 cases revealed different attitudes in the progress of coronary abnormalities. All large aneurysms showed a tendency to regress, although some progressed to stenotic lesions. Moderate aneurysms stayed unchanged, regressed, or progressed to stenosis or obstruction. Small aneurysm never became stenotic and frequently regressed to normal internal diameter. Aneurysms of the RCA tended to regress relatively early during the follow-up period, whereas those of the LCA gradually progressed to stenotic lesions. In 7 of 35 patients with RCA lesions, aneurysms progressed to complete obstruction and subsequent recanalization within 0.5 to 7.7 years (median 3.6 years) after the onset of KD. Most of the patients with coronary artery sequelae after KD remain asymptomatic. Serial angiographic observation is indicated for those patients who develop large coronary aneurysms during the acute phase of KD. The standard 12-lead electrocardiogram, chest roentgenogram, and exercise stress test are less sensitive for detecting and evaluating patients with coronary sequelae. For the screening of myocardial ischemia after KD, stress thallium 201 scintigraphy with dipyridamole infusion is recommended.

Aldose reductase and sorbitol dehydrogenase activities in diabetic brain: in vivo kinetic studies using 19F 3-FDG NMR in rats

The effects of diabetes mellitus on the kinetic constants of aldose reductase and sorbitol dehydrogenase in rat brain were investigated non-invasively in vivo using the 3-fluoro-3-deoxy-D-glucose (3-FDG) 19-fluorine (19F) nuclear magnetic resonance (NMR) method. While forward flux or both aldose reductase and sorbitol dehydrogenase (k1 and k2) were significantly increased, there was no corresponding increase in reverse flux (k3 and k4), and leakage of fructose (k5) was negligible. These findings indicate that the enzymatic kinetics of aldose reductase sorbitol (ARS) in diabetic brain undergo alteration favoring intracellular sorbitol and fructose accumulation, the frequently implicated biochemical basis of diabetic complications.

Telomerase activity is induced by the stimulation to antigen receptor in human peripheral lymphocytes

Impairment of replicating DNA ends by normal DNA polymerases and the gradual shrink of the ends of linear chromosomes (telomeres) is recently considered to play a role for the limited growth of cells. Telomerase activity, that uses an RNA template to extend telomeric DNA, appears in the malignant transformation of human cells. Freshly isolated normal lymphoid cells do not express any detectable telomerase activity. Interestingly, anti-CD3 monoclonal antibody (mAb) induces telomerase activity in human peripheral T cells. Ca ionophore and phorbol 12,13-dibutyrate (PDB), which are considered as the stimulants that bypass T cell receptor (TCR) signaling, also induce telomerase activity. These results clearly demonstrate that telomerase activity appears in normal lymphoid cells and suggest that antigen receptor-mediated induction of telomerase activity is playing a role in the proliferation of human T cells in the immune response.

Synaptic relationships between axon terminals from the mediodorsal thalamic nucleus and layer III pyramidal cells in the prelimbic cortex of the rat

A combined study of anterograde axonal degeneration and Golgi electron microscopic technique was designed to examine the distribution and density of axon terminals from the mediodorsal thalamic nucleus (MD) over layer III pyramidal cells in the prelimbic cortex of the rat. The reconstructive analysis of serial ultrathin sections of gold-toned apical and basal dendrites of layer III pyramidal cells showed that degenerating thalamocortical axon terminals from MD formed asymmetrical synaptic contacts predominantly with dendritic spines of the identified basal dendrites as well as apical dendrites. There was little difference in the numerical density of thalamocortical synapses from MD per unit length of both apical and basal dendrites.

Insertion of a pacing lead via the tricuspid valve does not affect cardiac function and tricuspid valve regurgitation in young dogs

A preliminary experimental study in dogs was conducted to evaluate the feasibility of transvenous cardiac pacing in the fetus with complete heart block associated with hydrops. Four young mongrel dogs were anesthetized with intravenous administration of sodium pentobarbital and mechanically ventilated, and a pacing lead was inserted via the tricuspid valve. The right ventricular cardiac output, aortic pressure and central venous pressure were measured, and the tricuspid valve regurgitation was measured semi-quantitatively using echo-Doppler color flow imaging. The relationship between the location of the pacing lead and the tricuspid valve regurgitation and cardiac function was examined. The mean right ventricular cardiac output when the pacing lead was inserted into the superior vena cava (126 +/- 54 mL/min per kg) was not significantly different from that when it was inserted into the right ventricle (110 +/- 43 mL/min per kg). The aortic pressure was 66 +/- 7.7 mmHg and 67 +/- 6.6 mmHg, respectively, and the central venous pressure 5.9 +/- 1.7 mmHg and 5.7 +/- 1.6 mmHg, respectively, under the two conditions (not significantly different). The ratio of demonstrating significant tricuspid valve regurgitation was 4/13 into the superior vena cava and 5/13 into the right ventricle, respectively (not significantly different). The location of the pacing lead did not change the cardiac function or the amount of the tricuspid valve regurgitation in our experimental study. It was therefore concluded that the transvenous cardiac pacing technique has potential application in intrauterine transvenous cardiac pacing in the fetus with complete heart block.

Association of multiple human papillomavirus types with vulvar neoplasias

OBJECTIVE

The purpose of this study was to clarify the association of multiple genital human papillomavirus (HPV) types with vulvar neoplasias.

METHODS

We examined vulvar neoplasias by the polymerase chain reaction (PCR) method, which can detect almost all genital HPV types sensitively (L1-PCR).

RESULTS

Eight HPV types (types 6, 11, 16, 18, 52, 53, 56, and 68) were detected in 52 of 53 (98.1%) vulvar condylomas; 2 HPV types (types 16 and 18) were detected in all 6 Grade-3 vulvar intraepithelial neoplasias; and 5 HPV types (types 6, 16, 18, 51, and 56) were detected in 8 of 11 (72.7%) invasive vulvar carcinomas. Detection of HPV types 52, 53, 56, and 68 in vulvar condylomas and detection of HPV types 51 and 56 in vulvar carcinomas are the first examples ever reported.

CONCLUSION

This study suggests that more HPV types are associated with the generation of vulvar neoplasias than was thought to be the case up to now.

Serum cholesterol levels in school-aged Japanese children: the Hisayama study

Hypercholesterolemia has been known to be an important factor in the development of atherosclelosis. Blood cholesterol screening and related health education in children, however, have not yet been widely practiced in Japan. From 1985 to 1990, blood samples were obtained from 5825 school children aged 6 to 14 years residing in Hisayama, Japan. The mean total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels were determined. The mean TC levels ranged from 155 to 172 mg/dL for boys and from 156 to 170 mg/dL for girls, peaking at 9 years for both sexes. The TG levels also tended to increase gradually and to peak at 11 years for both sexes. The tendency for TG levels to be higher was much clearer than in US children and adolescents. The HDL-C levels were highest at 9 years of age for both sexes and the LDL-C levels also tended to peak at 9 years of age for boys and at 8 years of age for girls. Atherogenic Indices [(TC-HDL-C)/HDL-C] ranged from 1.7 to 1.9 for boys and 1.8 to 2.0 for girls. As the cholesterol level of Japanese children would be expected to rise steadily reflecting their westernized lifestyle, preventive programes on a nationwide base including health education at school environments should be emphasized.

Alpha-fetoprotein-producing renal cell carcinoma with increased activity of N-acetylglucosaminyl-transferase III

N-acetylglucosaminyltransferase (GnT) III catalyzes the addition of N-acetylglucosamine through a beta 1-4 linkage to the mannose of the trimannosyl core, resulting in conversion of the concanavalin-A-(ConA)-reactive glycan into the ConA-nonreactive one. In this study, we measured GnT III levels in serum, tumor, and surrounding normal tissues together with a glucosaminylation index of alpha-fetoprotein (AFP), which is defined as the percentage of the ConA-nonreactive species in total AFP, in a case of AFP-producing renal cell carcinoma. The glucosaminylation index was determined by affinoelectrophoresis in the presence of ConA. GnT III was measured by using a pyridylaminated asialoagalactobiantennary sugar chain as a substrate by high-performance liquid chromatography. The glucosaminylation index of serum AFP, the concentration of which was 68 ng/ml, was 60%. This value is much higher than observed in hepatocellular carcinomas. The tumor tissue level of GnT III was 55.34 pmol/mg/h which was about six fold higher (9.50 pmol/mg/h) than in normal surrounding tissues. The serum level of this enzyme before surgery was 27.65 pmol/ml/h and decreased to 5.38 pmol/ml/h thereafter in association with a depression of serum AFP from 68 to 5.4 ng/ml. Thus, an increased level of GnT III in tumor tissues could account for the elevated conversion of a biantennary complex type sugar chain of AFP into a bisecting glucosaminylated biantennary one resulting from the addition of an N-acetylglucosamine residue at the trimannosyl core. This is, to our knowledge, the first report explaining the change in the carbohydrate structure of AFP with different affinity to ConA on the enzymatic basis in a renal cell carcinoma.

Nuclear magnetic resonance studies of sugar metabolism in the human infant lens

We investigated sugar metabolism in lenses isolated from infants with stage-5 retinopathy of prematurity (ROP). The lenses were incubated in 13C-labeled glucose (35.5 mM) or galactose (30 mM) for 24 h at 37.5 degrees C. Six to 8 lenses were pooled for each experiment. 13C-nuclear magnetic resonance spectroscopy was then performed on perchloric acid extracts of these lenses. Active aldose metabolism was indicated by the production of lactate. However, neither sorbitol nor dulcitol was detected. On the other hand, an experimental aldose reductase inhibitor, sorbinil, caused a decrease in the hexose monophosphate shunt activity suggesting an active polyol pathway. Both polyols therefore appeared to have been metabolized further. In addition, galactose metabolism was unique in that it not only involved a galactose-->glucose epimerization, but also a direct galactose-->ribose conversion, and a production of galactose-3-phosphate. Although it is possible that the ROP lenses have adapted to oxidative stress during the postnatal high-oxygen incubation for premature infants, we believe the observed sugar metabolism is representative of the developing human lens.

Molecular cloning of an isoform of Doc2 having two C2-like domains

We previously isolated a novel protein having two C2-like domains known to interact with Ca2+ and phospholipid, and named Doc2 (Double C2). Doc2 is predominantly expressed in brain and is implicated in Ca(2+)-dependent neurotransmitter release. We have isolated here an isoform of Doc2 and named the original one Doc2 alpha and the new one Doc2 beta. Doc2 beta alsp has two C2-like domains and is 61% identical to Doc2 alpha at the amino acid level. In contrast to Doc2 alpha, the Doc2 beta mRNA is expressed ubiquitously. These results indicate that there are at least two isoforms of Doc2, and suggest that Doc2 beta is involved in Ca(2+)-dependent intracellular vesicle trafficking in various types of cells.

Comparison of hemodynamic changes resulting from toxic shock syndrome toxin-1-producing Staphylococcus aureus sepsis and endotoxin-producing gram-negative rod sepsis in patients with severe burns

Five patients with burns and toxic shock syndrome toxin-1 (TSST-1)-producing Staphylococcus aureus sepsis (TSS group) were treated in a 5-year period at Kyorin University Hospital's Traumatology and Critical Care Center Burn Unit. Hemodynamic and metabolic differences in these patients were compared retrospectively with those in another five patients who were matched by burn index and age and in whom endotoxin-producing gram-negative rod sepsis developed (End group). Both groups showed hypermetabolic and hyperdynamic changes at the point sepsis developed. There were no significant differences between the two groups in any parameter. At the point septic shock developed, the TSS group showed significantly lower mean (+/- SD) arterial pressure (TSS vs End group, 64 +/- 5 vs 74 +/- 5 mm Hg; p < 0.05), significantly lower systemic vascular resistance index (TSS vs End group, 579 +/- 62 vs 729 +/- 75 dynes.sec.cm-5/m2; p < 0.05), and higher oxygen consumption (TSS vs End group, 190 +/- 7 vs 163 +/- 11 L/min/m2; p < 0.05) compared with the End group. This is the first clinical report that asserts that TSST-1-producing gram-positive sepsis may result in more hypermetabolic and hyperdynamic differences than does endotoxin-producing gram-negative rod septic shock. These responses may indicate a stronger stimulation of cytokine and nitrous oxide synthetic activity by TSST-1 than by endotoxin.

Detection of hypervascular hepatocellular carcinoma by dynamic MRI and dynamic spiral CT

OBJECTIVE

Our goal was to evaluate the detectability of hypervascular hepatocellular carcinomas (HCCs) by multislice dynamic MRI and dynamic spiral CT.

MATERIALS AND METHODS

Prior to transcatheter arterial chemoembolization (TACE) with iodized oil, the liver was subjected to T1- and T2-weighted SE-MRI, multislice dynamic MRI after intravenous bolus injection of Gd-DTPA, early phase imaging with spiral CT (dynamic spiral CT) after intravenous bolus injection of contrast medium (at a rate of 2 or 3 ml/s), and delayed phase CT in 64 patients with 208 HCC nodules. The detectability of HCCs by MRI and CT was evaluated retrospectively compared with CT after TACE as a gold standard.

RESULTS

The detectability of nodules < 1 cm in diameter was superior with dynamic MRI (67%) and dynamic spiral CT (50%) in comparison with SE-MRI (26%) and delayed phase CT (11%) (p < 0.01). The detectability of these tumors with dynamic MRI was significantly superior to that with dynamic spiral CT using an injection rate of 2 ml/s (p < 0.01), but not significantly different from that of dynamic spiral CT using a rate of 3 ml/s.

CONCLUSION

Dynamic MRI and dynamic spiral CT are comparable for detecting hypervascular intrahepatic metastases of HCC.

Blood pressure levels in school-age Japanese children: the Hisayama Study

Blood pressure (BP) measurements were obtained on a total of 6325 children (3294 boys and 3031 girls), aged 6-14 years, in Hisayama, Japan. All BPs were recorded in a sitting position by trained observers in a standardised manner. Standard mercury sphygmomanometers were used with commercially available cuffs, selected according to the arm circumference. Cuff size no. 3 (bladder width 9 cm, length 23 cm) was the one most commonly selected in 84% of elementary schoolers aged 6-11 years and in 35% of junior high schoolers aged 12-14 years. Mean systolic BPs (SBPs) increased from 89 mm Hg at age 6 years to 108 mm Hg at 14 years (a 21% increase) for boys and from 88 mm Hg to 102 mm Hg (a 16% increase) for girls. Diastolic BP (DBPs, Korotkoff phase IV, KIV) increased from ages 6 to 14 years to the same degree, from 58 mm Hg to 72 mm Hg (a 24% increase) for boys and from 58 mm Hg to 70 mm Hg (a 21% increase) for girls. The increase in DBP (Korotkoff phase V, KV) was greater, from 48 mm Hg to 63 mm Hg (a 30% increase) for boys and from 48 mm Hg to 61 mm Hg (a 28% increase) for girls. The increase in mean SBP for adolescent boys was greater compared with that of girls; however, separation of age-specific values by sex was not observed for mean DBP (KIV) and DBP (KV). The cross-sectional relation between age and mean SBP levels was not linear.

Tumor necrosis factor production by human T-cells stimulated with bacterial superantigens

Tumor necrosis factor (TNF) production from T-cells stimulated with superantigenic exotoxins, staphylococcal enterotoxin B and streptococcal pyrogenic exotoxin A was investigated in the presence of cells bearing distinct isotypes of HLA class II molecules. The main T-cell subset for TNF production was investigated in parallel. Similarly high levels of TNF production were induced upon stimulation with the toxins in the presence of DR+ or DQ+ cells, but only marginal levels of TNF production were induced in the presence of DP+ cells. Although both CD4+ T-cells and CD8+ T-cells produced TNF-alpha and TNF-beta in response to toxin stimulation in the presence of HLA class II+ cells, the former T-cell subset was the major source of producers of TNF-alpha and TNF-beta.

Protective effect of granulocyte colony-stimulating factor against T-cell-meditated lethal shock triggered by superantigens

The bacterial superantigens (SAg), toxic shock syndrome toxin-1 (TSST-1) and staphylococcal enterotoxin B (SEB), are powerful T-cell stimulators, triggering systemic release of lymphokines causing lethal shock in D-galactosamine (D-Gal)-sensitized mice. We show that pretreatment with recombinant human granulocyte colony-stimulating factor (rhG-CSF) protects mice against T-cell-mediated SAg-shock. In mice challenged with D-Gal/TSST-1, lethal shock was caused within 30 hours. In contrast, animals pretreated with two consecutive subcutaneous injections of 2 micrograms rhG-CSF with a 12-hour time interval showed only marginal signs of illness and no lethality after challenge with D-Gal/TSST-1. Mice treated with 5 micrograms rhG-CSF either 12 or 6 hours in advance also survived otherwise lethal doses of D-Gal/TSST-1. The protective effects of rhG-CSF pretreatment was also evident against lethal doses of D-Gal/SEB challenge and this protection was accompanied by suppression of systemic interleukin-2. However, rhG-CSF affected neither the proliferative responses of SAg-reactive T cells in vivo or in vitro nor their interleukin-2 production in vitro, implying that rhG-CSF may indirectly interfere with cytokine synthesis in T cells but not with T-cell-SAg binding itself. These results represent another beneficial effect of rhG-CSF as an anti-inflammatory agent against T-cell-mediated toxicity triggered by SAg.

The absence of evidence of staphylococcal toxin involvement in the pathogenesis of Kawasaki disease

To detect a causative superantigen and to clarify a possible role for staphylococci in Kawasaki disease (KD), culture supernatants of individual bacterial isolates from 11 acute-stage patients were studied. Toxic shock syndrome toxin-1 (TSST-1) and antibody to TSST-1 and enterotoxins A (SEA), B (SEB), and C (SEC) in acute (mean, day 7) and late convalescent (mean, month 15) sera from 26 patients (12 with coronary artery aneurysms) and 22 age-matched controls were measured. Only 1 of 60 supernatants was mitogenic for human lymphocytes; it was 1 of the 4 Staphylococcus aureus isolates. Mitogenicity was neutralized by sera obtained after administration of intravenous gamma globulin (mean, week 4) but not by late convalescent sera. TSST-1 was detectable in 2 of 26 acute sera and 1 of 22 control sera. No KD but 1 control serum had IgM to TSST-1. IgG seroconversion rates to TSST-1, SEA, SEB, and SEC were 10%, 15%, 21% and 16%, respectively. These data do not support the involvement of toxin-producing staphylococci in KD.

A simple and effective video keratometric system

We tested a personal computer-based video keratometric system used to analyze projected placido disk rings. The system consists of a Maloney surgical keratometer that projects the rings and a video camera attached to an operating microscope. Images of the rings were transmitted to a video image processing board and analyzed on a personal computer using an analysis program we developed. System precision was evaluated in 18 eyes. The values were compared with those obtained using a commercial photokeratometer (control). In all eyes, the principal meridian values differed from the controls by < 0.04 mm. In 15 eyes (83%), the measurements were within 0.03 mm of the controls. The corneal astigmatism values and cylindrical axes were within 0.12 diopters in 17 eyes (94%) and within 5 degrees in all cases, respectively. Our system, which can analyze placido disc rings projected from other systems, is sufficiently precise to measure the corneal radius of curvature and astigmatism.

Detectability of hypervascular hepatocellular carcinoma by arterial phase images of MR and spiral CT

The ability of arterial phase images of breath-hold MR imaging and spiral CT to detect hypervascular hepatocellular carcinomas (HCCs) was evaluated. Prior to transcatheter arterial chemoembolization (TACE) with iodized oil, MR images and spiral CT during i.v. bolus injection of contrast medium (IV-MR imaging and IV-spiral CT) and spiral CT during intraarterial injection of contrast media through catheter (IA-spiral CT) of the entire liver were obtained in 24 consecutive patients with 93 HCCs. In the detection of HCCs less than 1 cm in diameter, IA-spiral CT (87.3%) was superior to IV-MR imaging (63.5%) and IV-spiral CT (54.0%) (p < 0.001). There was no significant difference in detectability in any tumor size between IV-MR imaging and IV-spiral CT. IA-spiral CT was the best for detecting hypervascular HCCs, and there was no significant difference between IV-MR imaging and IV-spiral CT.

[An analysis of factors related to recurrence of superficial bladder cancer after transurethral resection]

A total of 205 patients with primary superficial bladder cancer (Ta, T1) followed more than 3 years were retrospectively analyzed for factors related to recurrence of tumors after transurethral resection. Patients age were 25 to 90 years old, average 61 years old, and there were 160 males and 45 females. Initial tumor grades were G0 in 4 patients, G1 in 48, G2 in 134 and G3 in 19. Seventy four patients had Ta tumor and 131 had T1. Initial treatments were transurethral resection (TUR) alone in 137 patients. TUR with intravesical chemotherapy in 64, with BCG therapy in 7 and others in 7. Factors examined included age, sex, chief complaint, shape, size, and number of tumors, tumor distribution (single area or multiple area), histological grade, stage and intravesical chemotherapy. Overall non-recurrent rate were 81.7% at 1 year, 60.7% at 3 year, 53. 8% at 5 year and 44.2% at 8 year. Five-year non-recurrent rate according tumor factors, showed significant difference regarding tumor size (< 1 cm or 1 cm <: P = 0.027), tumor number (single or multiple: P = 0.004), tumor distribution (single area or multiple area: p = 0.002), histological grade (< G1 or G2 < : p = 0.001) and stage (Ta or T1: p = 0001). However, there were no significant difference regarding factors of age, sex, chief complaint, tumor figure and presence or absence of intravesical chemotherapy. This results suggested that the tumor factors of size, number, tumor distribution, grade and stage were highly related to intravesical tumor recurrence of superficial bladder cancer.

Efficient and specific induction of esophageal tumors in rats by precursors of N-nitrososarcosine ethyl ester

Cancers and precancerous lesions of the esophagus were efficiently induced in rats by the simulation of a clinico-epidemiological setting; that is, the administration of precursors of nitrosamine. Six week old non-inbred male Wistar rats were given 2g/kg bodyweight of sarcosine ethyl ester hydrochloride (SEEH) and concurrently 0.3g/kg bodyweight of sodium nitrite (NaNO2), precursors of N-nitrososarcosine ethyl ester (NSEE), in 2% sucrose as drinking water. Group 1 received the precursors twice a week for 6 weeks followed by 8 weeks observation, and group 2, once every 3 days for 7 weeks followed by 26 weeks observation. At the end of treatment, no tumor had developed in the esophagus of rats in group 1, but the [3H]-thymidine labeling indices in both basal and superficial layer cells were higher than in the control group. On subsequent observation, papillomas appeared in group 1 (33.3%), and carcinomas in group 2 (33.3%), within 4 weeks. The tumors induced in group 1 were mostly papillomas and rarely carcinomas. When the observation was prolonged in group 2, 100% of the animals had cancer in week 20. The pathological changes of the lesions paralleled the sequential development of human squamous cell carcinoma of the esophagus. Our system has the advantages in that papillomas and cancers can be induced in rats in a short time and the agents used are less toxic than preformed nitrosamines administered previously by gastric intubation. It would serve as a useful experimental tool to study premalignant lesions and cancers of the esophagus.

Hepatocyte growth factor specifically expressed in microglia activated Ras in the neurons, similar to the action of neurotrophic factors

Hepatocyte growth factor (HGF) mRNA and its receptor (c-Met) mRNA were detected in the fetal and adult rat brain. Expression of c-Met mRNA was increased after birth. HGF mRNA was preferentially expressed in the microglia of the rat brain, while c-Met mRNA was expressed in neurons as well as astrocytes and microglia. Most of the neurons were c-Met positive, and HGF stimulated tyrosine phosphorylation of c-Met (140-kDa) in the neurons. HGF as well as bFGF also activated Ras in the neurons. These results suggest that HGF plays a biological role as one of the neurotrophic factors in the brain.

[Quinolone-resistant mutations in Neisseria gonorrhoeae]

For 10 strains of Neisseria gonorrhoeae exhibiting decreased susceptibility to new quinolones (MIC, > or = 0.1 microgram/ml) isolated and preserved from patients with gonococcal urethritis during the period from February 1991 through January 1992. We investigated the mechanisms for development of resistance to new quinolones. After selecting 3 PCG-sensitive and new quinolone-resistant strains from among these strains, we first carried out transformation experiments of N. gonorrhoeae using a plasmid carrying the E. coli gyrA gene. We then determined the base sequence on the N. gonorrhoeae gyrA gene by PCR method. Of the 3 strains in which transformation experiments were carried out, 2 strains yielded transformants, one of which was 8 times more sensitive to norfloxacin (NFLX) than the original strain, and it was assumed that this strain has a mutation in the gyrA gene. In our study of the base sequence on the N. gonorrhoeae gyrA gene using the PCR method, both strains had the mutation of Ser 83 (TCC)-->Phe (TTC), and in addition to this mutation of Ser-->Phe, one other strain had the mutation of Asp-87 (GAC)-->Gly (GGC). This type of mutation of quinolone-resistant N. gonorrhoeae on the gyrA gene has high homology with the mutations reported for Escherichia coli and other strains and there appears to be a close correlation between the increasing frequency of use of the new quinolones in this country and the spread of such resistant strains of N. gonorrhoeae.

Proliferative response and cytokine production of bovine peripheral blood mononuclear cells induced by the superantigens staphylococcal enterotoxins and toxic shock syndrome toxin-1

The potential of staphylococcal enterotoxin A (SEA), B (SEB), C(SEC) and toxic shock syndrome toxin-1 (TSST-1) to act as superantigens by inducing polyclonal T-cell mitogenesis and cytokine production was tested on bovine peripheral blood mononuclear cells (PBMC). These four toxins were capable of inducing strong proliferative response of PBMC from calves over a broad dosage range (1 pg/ml to 1 microgram/ml) in vitro. The toxin-activated blast cells consisted of both CD4+ T-cells and CD8+ T-cells, but the T-cell proliferation depended upon the presence of monocytes. Treatment of monocytes with monoclonal antibody to major histocompatibility complex class II antigens substantially inhibited the toxin-induced T-cell proliferative response, but paraformaldehyde-fixation did not abrogate the accessory function. SEA, SEB, SEC and TSST-1, all induced the in vitro release of interleukin-2, interferon gamma and tumor necrosis factor alpha in a dose dependent manner. The results indicate that SEA, SEB, SEC and TSST-1 are capable of acting as superantigens by stimulating bovine T-cells as shown in the human and murine systems. The possible implications of these toxins in the immunopathogenesis of bovine mastitis caused by the infection with Staphylococcus aureus are discussed.