Transmission of Rickettsia tsutsugamushi strains among humans, wild rodents, and trombiculid mites in an area of Japan in which tsutsugamushi disease is newly endemic

Thirty-two newly isolated strains of Rickettsia tsutsugamushi, 14 from patients with tsutsugamushi disease, 12 from wild rodents, and 6 from trombiculid mites parasitizing rodents in Gifu Prefecture, Japan, were examined for reactivities to 12 monoclonal antibodies by an indirect fluorescent-antibody test to classify their antigenicities. All of the isolates could be classified into one of six groups (KN-1, KN-2, KN-3, GJ-1, R158, and R161) according to their reactivities to the monoclonal antibodies. The KN-1 and GJ-1 strains that are prevalent among patients from Gifu Prefecture had the same reactivities as the Kawasaki and Kuroki strains, respectively, which have been isolated and are prevalent in the Miyazaki and Kagoshima prefectures in southwest Japan. The isolates from patients were different in serotype from those from rodents and mites (Leptotrombidium pallidum). The KN-2 and KN-3 strains were most prevalent among patients and among rodents and mites, respectively. No close similarity between KN-2 and other strains tested was observed. KN-3 is only a minor contributor to diseases in patients in Gifu Prefecture; however, it was proven that the same strain was prevalent in Niigata Prefecture in northern Japan. Thus, Gifu Prefecture is an area where southern, northern, and local strains are found. We hypothesize that humans are prone to infection with KN-2, GJ-1 (very similar to Kuroki), and KN-1 (very similar to Kawasaki), probably by infestation with Leptotrombidium scutellare. While both L. scutellare and L. pallidum parasitize wild rodents and may carry any rickettsial strain, the most virulent strain, KN-3, is predominant among wild rodents. Antigenic analysis using monoclonal antibodies to R. tsutsugamushi should be useful for epidemiological studies of infection with this organism.

The effect of ethanol on lateral and rotational mobility of plasma membrane vesicles isolated from cultured Mar 18.5 hybridoma cells

Intramolecular excimer formation of 1,3-di(1-pyrenyl)propane (Py-3-Py) and fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) were used to evaluate the effect of ethanol on the rate and range of the lateral mobility and the range of the rotational mobility of bulk bilayer structures of the plasma membrane vesicles (ATCC-PMV) isolated from cultured hybridoma cells (ATCC TIB 216). In a concentration-dependent manner, ethanol increased the excimer to monomer fluorescence intensity ratio (I'/I) of Py-3-Py in the ATCC-PMV and decreased the anisotropy (r), limiting anisotropy (r infinity) and order parameter (S) of DPH in the ATCC-PMV. This indicates that ethanol increased both the lateral and rotational mobility of the probes in the ATCC-PMV. Selective quenching of DPH by trinitrophenyl groups was utilized to examine the range of transbilayer asymmetric rotational diffusion of the ATCC-PMV. The anisotropy (r), limiting anisotropy (r infinity) and order parameter (S) of DPH in the inner monolayer were 0.024, 0.032, and 0.069, respectively, greater than calculated for the outer monolayer of the ATCC-PMV. Selective quenching of DPH by trinitrophenyl groups was also used to examine the transbilayer asymmetric effects of ethanol on the range of the rotational mobility of the ATCC-PMV. Ethanol had a greater increasing effect on the range of the rotational mobility of the outer monolayer as compared to the inner monolayer of the ATCC-PMV. It has been proven that ethanol exhibits a selective rather than nonselective fluidizing effect within the transbilayer domains of the ATCC-PMV.

Pathologic study of mice infected with Rickettsia tsutsugamushi R19 strain

Scrub typhus, an acute febrile infectious disease caused by R. tsutsugamushi, has been reported from various parts of the far east and pacific rim of Asia including Korea. It is well known that all human pathogenic rickettsia share an affinity to endothelial cells of the small blood vessels and evoke vascular inflammation variably associated with a rash, microthrombi, and hemorrhage. We infected the ICR mice by inoculating sublethal doses of R. tsutsugamushi R19 strain intraperitoneally and observed the pathologic changes by time sequence. The histopathologic features of experimentally induced scrub typhus in the mice were generally nonspecific interstitial inflammations characterized by interstitial pneumonitis, periportal inflammation, multifocal hepatic necrosis, interstitial nephritis, sinusoidal engorgement, and lymphohistiocytic cell infiltration in lymph nodes and spleen. Contrary to the general features of other rickettsial diseases, the pathologic process of scrub typhus experimentally induced by R. tsutsugamushi R19 strain mainly involved the interstitial connective tissue but not the blood vessels.

Magnetic resonance imaging in the evaluation of the lumbar herniated intervertebral disc

Two hundred and eleven patients with lumbar disc herniation at 242 levels were divided into 5 groups by their appearances on magnetic resonance imaging (MRI), and the findings at operation were compared to assess the accuracy of the MRI classification. There were no negative explorations. There was 92% sensitivity, 91% specificity and 92% accuracy for MRI in distinguishing protruded discs from other forms of lumbar disc herniation. For sequestrated discs there was 92% sensitivity, 99% specificity and 97% accuracy. In the extruded subligamentous type there was 71% sensitivity, 82% specificity and 79% accuracy, and 52% sensitivity, 92% specificity and 81% accuracy in the extruded transligamentous type. The overall accuracy of MRI predicting the types of herniated lumbar intervertebral disc was 85%. High resolution MRI is sensitive in detecting disc disease and specific in characterizing various subgroups of disc herniation, especially those which are sequestrated.

Rapid diagnosis of scrub typhus by a passive hemagglutination assay using recombinant 56-kilodalton polypeptides

The genes encoding the 56-kDa polypeptides were amplified by polymerase chain reaction from the genomic DNAs of three serotypes of Rickettsia tsutsugamushi, Gilliam, Karp, and Boryong. The amplified products were cloned into expression vector pIH821, and the recombinant antigens were expressed in Escherichia coli as fusion proteins with maltose-binding protein. The recombinant 56-kDa polypeptides were purified by affinity chromatography for the sensitization of sheep erythrocytes. The recombinant 56-kDa polypeptides were evaluated with 89 serum specimens from health blood donors, 94 serum specimens from scrub typhus patients, and 31 serum specimens from patients with other febrile diseases by a passive hemagglutination assay (PHA). Among the scrub typhus patients diagnosed by indirect immunofluorescent-antibody testing, the antibodies to R. tsutsugamushi were detected in 93 patients (99%). One serum specimen from a healthy person showed a false-positive reaction by this method. The recombinant PHA showed no cross-reactions with sera obtained from other febrile patients with diseases such as murine typhus, hemorrhagic fever with renal syndrome, and leptospirosis. In conclusion, this recombinant PHA could be substituted for the conventional indirect immunofluorescent-antibody test and the immunoperoxidase test.

Enoxacin photosensitivity

A 71-year-old Korean farmer had pruritic erythematous patches on sun-exposed areas after enoxacin treatment for prostatitis. Suggestive features of photoallergy, such as moderate blurring of the margin and possible ectopic flare phenomenon, were reproduced by oral provocation test with enoxacin. Because all quinolones have structural similarities, and photosensitivity was observed in nalidixic acid and enoxacin, it would be advisable to warn all patients taking quinolones about photosensitivity.

Transient temperature responses of hydronic radiant floor heating system by different pipe embedding depth and water supply condition

"Ondol" is a Korean unique heating system. It is a specific radiant floor heating system using combustion heat of briquette or timber in Korea. Such traditional "Ondol" is changed to radiant heating system with pipe-coil embedded in the floor or slab. This study has contributed to the understandings of the transient behaviours of Ondol-heated floor panels and enclosure exposed to this type of heating system. The result is that the water supply temperature had a large effect on the rate of increase in floor surface and room air temperature. But, in spite of a higher water supply temperature, the heat flow rate was not increased considerably. The shallow pipe embedding depths, of course, result in a low heat flow rate.

The C-reactive protein (CRP) in patients with long bone fractures and after arthroplasty

Between March 1991 and February 1992 serial serum C-reactive protein (CRP) levels were measured prospectively for three weeks in 57 consecutive patients with fractures of long bones, and also in 11 patients who had undergone primary total hip or knee arthroplasty. A semi-quantitative capillary floculation method was used for measuring the CRP level. The highest values were usually recorded 2-3 days after trauma or operation, and the CRP was nearly normal by three weeks. In the patients with long bone fractures the amplitude of CRP response was affected by the type of treatment. Lower values were observed in those patients treated conservatively than in those who underwent operation, but the profile of CRP response was similar, regardless of the type of treatment. The CRP response was also affected by the severity of the trauma in conservatively treated patients, but in those who underwent operation the CRP response was similar, regardless of the severity of the injury. In patients with primary total hip or knee arthroplasty the pattern of CRP response after operation was similar to that in the patients with long bone fractures who underwent surgical treatment. Awareness of the natural course of the CRP response after fracture and arthroplasty may help in the diagnosis of early post-traumatic and postoperative complications, especially infections.

Coupling of GTP-binding to the T cell receptor (TCR) zeta-chain with TCR-mediated signal transduction

The zeta-subunit of the TCR binds GTP and is a well characterized substrate for a TCR-activated tyrosine kinase. To examine the possible coupling of GTP-binding to zeta with TCR-mediated signal transduction, a mutant (termed J32-3.2) of the T cell line Jurkat (J32) was used. Anti-TCR/CD3 stimulation of the TCR/CD3+ J32-3.2 cells resulted in a weak stimulation of both the phosphatidyl inositol and tyrosine kinase signal transduction pathways, as measured by changes in the level of free intracellular calcium, tyrosine phosphorylation of TCR-zeta, CD3-epsilon and ZAP-70, p56lck, or p59fyn tyrosine kinase activity and IL-2 gene activation. The impaired responsiveness of J32-3.2 cells to anti-TCR/CD3 mAb correlated with a low basal level of GTP-binding to zeta. Furthermore, in J32-3.2 cells TCR activation by antibody ligation caused a weaker increase in GTP-binding to the zeta-chain, as compared with that of wild-type J32 cells, which indicates for the first time that GTP-binding to zeta can be modulated by extracellular signals and suggest that the role of GTP-binding to zeta is to couple the TCR to intracellular signal transduction mechanisms.

Coupling of GTP-binding to the T cell receptor (TCR) zeta-chain with TCR-mediated signal transduction

The zeta-subunit of the TCR binds GTP and is a well characterized substrate for a TCR-activated tyrosine kinase. To examine the possible coupling of GTP-binding to zeta with TCR-mediated signal transduction, a mutant (termed J32-3.2) of the T cell line Jurkat (J32) was used. Anti-TCR/CD3 stimulation of the TCR/CD3+ J32-3.2 cells resulted in a weak stimulation of both the phosphatidyl inositol and tyrosine kinase signal transduction pathways, as measured by changes in the level of free intracellular calcium, tyrosine phosphorylation of TCR-zeta, CD3-epsilon and ZAP-70, p56lck, or p59fyn tyrosine kinase activity and IL-2 gene activation. The impaired responsiveness of J32-3.2 cells to anti-TCR/CD3 mAb correlated with a low basal level of GTP-binding to zeta. Furthermore, in J32-3.2 cells TCR activation by antibody ligation caused a weaker increase in GTP-binding to the zeta-chain, as compared with that of wild-type J32 cells, which indicates for the first time that GTP-binding to zeta can be modulated by extracellular signals and suggest that the role of GTP-binding to zeta is to couple the TCR to intracellular signal transduction mechanisms.

Dietary glucose and fat attenuate effects of adrenalectomy on energy balance in ob/ob mice

The body energy balance response of ob/ob mice to adrenalectomy is diet dependent. Diets varying in source of carbohydrate (starch, glucose or fructose), fat to starch ratio, or fat to glucose ratio were fed to determine influences on energy balance in female adrenalectomized ob/ob mice. Adrenalectomy lowered food intake in all ob/ob mice to values comparable to those of lean mice independent of diet, but the percentage of dietary energy retained as body energy in adrenalectomized ob/ob mice was lowered to values comparable to those of lean mice only in mice fed starch or fructose, not in mice fed glucose or fat. Consumption of either high glucose or high fat diets blocked about one-half the overall effect of adrenalectomy on energy balance in ob/ob mice. Hyperinsulinemia was associated with the high efficiency of energy retention observed in adrenalectomized ob/ob mice fed glucose, but high efficiency of energy retention occurred in adrenalectomized ob/ob mice fed high fat diets without concomitant hyperinsulinemia. Adrenalectomy-induced changes in brain weight and protein content, body protein content and plasma thyroid hormone concentrations in ob/ob mice were independent of diet consumption. Combined adrenalectomy-ovariectomy diminished, but did not eliminate, the diet-dependent influences on energy balance in ob/ob mice. In conclusion, dietary glucose and dietary fat both attenuate effects of adrenalectomy on energy balance in ob/ob mice by promoting high efficiencies of energy retention.

Electro-olfactogram and multiunit olfactory receptor responses to complex mixtures of amino acids in the channel catfish, Ictalurus punctatus

In vivo electrophysiological recordings from populations of olfactory receptor neurons in the channel catfish, Ictalurus punctatus, clearly showed that both electro-olfactogram and integrated neural responses of olfactory receptor cells to complex mixtures consisting of up to 10 different amino acids were predictable with knowledge of (a) the responses to the individual components in the mixture and (b) the relative independence of the respective receptor sites for the component stimuli. All amino acid stimuli used to form the various mixtures were initially adjusted in concentration to provide approximately equal response magnitudes. Olfactory receptor responses to both multimixtures and binary mixtures were recorded. Multimixtures were formed by mixing equal aliquots of 3-10 different amino acids. Binary mixtures were formed by mixing equal aliquots of two equally stimulatory solutions. Solution 1 contained either one to nine different neutral amino acids with long side-chains (LCNs) or one to five different neutral amino acids with short side-chains (SCNs). Solution 2, comprising the binary mixture, consisted of only a single stimulus, either a LCN, SCN, basic, or acidic amino acid. The increasing magnitude of the olfactory receptor responses to mixtures consisting of an increasing number of neutral amino acids indicated that multiple receptor site types with highly overlapping specificities exist to these compounds. For both binary mixtures and multimixtures composed of neutral and basic or neutral and acidic amino acids, the receptor responses were significantly enhanced compared with those mixtures consisting of an equal number of only neutral amino acids. These results demonstrate that receptor sites for the basic and acidic amino acids, respectively, are highly independent of those for the neutral amino acids, and suggest that a mechanism for synergism is the simultaneous activation of relatively independent receptor sites by the components in the mixture. In contrast, there was no evidence for the occurrence of mixture suppression.

High jejunal obstruction as a sequela of necrotizing enterocolitis

A case of high jejunal obstruction due to stricture is reported. It is a rare form of late sequelae of neonatal necrotizing enterocolitis(NEC). Barium contrast study of the small bowel is recommended for earlier diagnosis and treatment before discharge from the hospital, even is an asympto-matic patient.

Serological classification by monoclonal antibodies of Rickettsia tsutsugamushi isolated in Korea

Antigenic types of 113 strains of Rickettsia tsutsugamushi isolated from Korean patients were analyzed by using murine polyclonal and monoclonal antibodies. The isolates can be classified in six groups according to their reaction to a panel of monoclonal antibodies. Nine isolates of group I were identified as the Gilliam serotype, and 13 isolates of groups II and III were identified as the Karp serotype. There were two groups that were considered to be a mixture of groups I and II or groups I and III, respectively. The remaining 88 strains of group IV had a unique antigenic determinant that was not present in the prototype strains (Karp, Kato, Gilliam), in addition to sharing common antigens with the prototype strains. Therefore these strains, which are more prevalent in Korea, seem to belong to a new serotype closely related to the Karp serotype.

Effect of calcium on blood pressure, platelet aggregation and erythrocyte sodium transport in Dahl salt-sensitive rats

Forty 11-week-old Dahl salt-sensitive rats were divided into four groups matched for blood pressure and weight. Group I was given a sodium-deficient diet, group II a sodium-enriched diet, group III a sodium-enriched diet plus a calcium supplement and group IV a sodium-enriched diet plus nitrendipine, a calcium antagonist. For the first 18 weeks, when the sodium-enriched diet contained 2.6% sodium, there were no differences in blood pressure between the groups; the sodium content was then increased to 8%, and the diets continued for 12 more weeks. At 41 weeks old, the rats in group II had significantly (P less than 0.05) higher systolic blood pressures than the other groups. Erythrocytes from the rats on the low-sodium diet had significantly (P less than 0.025) lower intracellular sodium (3.9 +/- 0.4 mmol/l) while cells from the rats given nitrendipine had significantly (P less than 0.005) higher intracellular sodium (13.3 +/- 0.8 mmol/l) than those from the rats on a high-salt diet (7.4 +/- 1.4 mmol/l). Nitrendipine caused significant (P less than 0.05) decreases in both ouabain-sensitive and furosemide-sensitive sodium efflux. Platelet aggregation in response to 2 mumol/l adenosine diphosphate was not significantly affected by the nitrendipine. The evidence that nitrendipine markedly affects sodium transport supports the hypothesis that an interaction of calcium and sodium may be involved in blood pressure control.

Effects of cimetidine, progesterone, cannitracin and tolazoline on the weight and DNA content of the testosterone-induced hyperplastic prostate of the rat

The antiandrogenic potency of cimetidine, progesterone, cannitracin and tolazoline was studied in intact immature rats by determination of the weight and DNA content of the ventral prostate. Cimetidine is a H-2-receptor histamine antagonist, cannitracin is an antifungal antibiotic derived from Strp-griseus and tolazoline is an alpha-adrenergic blocker similar to phentolamine. All rats (except the control group) received testosterone propionate (TP) 0.3 mg s.c. with the drugs above every day for one week. Cimetidine, progesterone and cannitracin, but not tolazoline, significantly decreased the weight and DNA content of the hyperplastic prostate induced by TP. The results indicate that cimetidine, progesterone and cannitracin have an antiandrogenic effect. This study provides the basis for investigating the effects of antiandrogen in men with symptomatic benign prostatic hyperplasia.

Purulent umbilical drainage from infection of left umbilical artery associated with open umbilicoperitoneal communication

This is a case report of a 20-day-old girl with persistent umbilical drainage due to infection of the left umbilical artery that ruptured at the base of the umbilicus and formed an open umbilicoperitoneal communication.

Gastrointestinal phytobezoars in childhood

We reviewed 33 children under the age of 15 with gastrointestinal phytobezoars. Twenty were boys and 13 were girls. Nearly all patients were observed in late fall and winter. In 22 patients, symptoms developed following ingestion of several ripe or dried persimmons with seeds but none had a history of unripe persimmon ingestion. All patients but three underwent enterotomy, gastrotomy, or enterotomy combined with gastrotomy for bezoar removal. The remaining three had small bowel resection due to strangulation. There was a single location of the bezoar in 85% and multiple locations in 15% at operation. Emergency laparotomy was performed on 25 patients who had typical mechanical intestinal obstruction revealed the plain abdominal films. It is not surprising that persimmon is the most common cause of bezoar formation in Korea, because it is a favorite fruit among Koreans, either in hard, soft, or dried variety.

Purification of heat-labile enterotoxin from an enterotoxin from an enterotoxigenic Escherichia coli of human origin by monoclonal immunoaffinity chromatography

Heat-labile enterotoxin (LT) was purified from an enterotoxigenic Escherichia coli 015H11 of human origin. The purification steps included French pressure cell disruption of the bacteria, salting-out, DEAE-Sephacel on chromatography. Application of this procedure resulted in a 95.1-fold purification of LT with a yield of 19.9% as determined by rabbit ileal loop assay. The final LT preparation showed only one protein-staining band on polyacrylamide gel electrophoresis, indicating that the purified LT was homogeneous.