Transient bacteremia after tooth extraction with intravenous cefuroxime prophylaxis

Twenty-four blood samples obtained after tooth extraction with intravenous cefuroxime prophylaxis were cultured on Bactec NR16A and NR 17A (Becton Dickinson, Maryland, U. S. A.). MIC of identified microbes and the serum levels of cefuroxime were also measured. The overall incidence of bacteremia was 16.7% (four out of 24). Although nine strains were isolated, no streptococcal bacteremia occurred. The MICs of cefuroxime varied from 0.05 to 12.5 micrograms/ml, and serum levels ranged from 100 to 233 micrograms/ml, which were satisfactory concentrations for the microorganisms isolated. The results suggested that intravenous cefuroxime prophylaxis for tooth extraction reduced the incidence of bacteremia, as well as the isolation rate of streptococci, significantly.

Restriction-modification systems as genomic parasites in competition for specific sequences

Restriction-modification (RM) systems are believed to have evolved to protect cells from foreign DNA. However, this hypothesis may not be sufficient to explain the diversity and specificity in sequence recognition, as well as other properties, of these systems. We report that the EcoRI restriction endonuclease-modification methylase (rm) gene pair stabilizes plasmids that carry it and that this stabilization is blocked by an RM of the same sequence specificity (EcoRI or its isoschizomer, Rsr I) but not by an RM of a different specificity (PaeR7I) on another plasmid. The PaeR7I rm likewise stabilizes plasmids, unless an rm gene pair with identical sequence specificity is present. Our analysis supports the following model for stabilization and incompatibility: the descendants of cells that have lost an rm gene pair expose the recognition sites in their chromosomes to lethal attack by any remaining restriction enzymes unless modification by another RM system of the same specificity protects these sites. Competition for specific sequences among these selfish genes may have generated the great diversity and specificity in sequence recognition among RM systems. Such altruistic suicide strategies, similar to those found in virus-infected cells, may have allowed selfish RM systems to spread by effectively competing with other selfish genes.

Atrophic nerve fibers in regions of reduced MIBG uptake in doxorubicin cardiomyopathy

A myocardial MIBG-SPECT examination was conducted 2 wk after doxorubicin chemotherapy on a 52-yr-old woman without cardiac symptoms. Despite normal 201TI scintigraphy, reduced MIBG uptake was detected in the apical anterior, inferior and lateral segments of the left ventricle. The patient died of congestive heart failure due to doxorubicin-induced cardiomyopathy 10 mo later. At necropsy, the left ventricle was markedly dilated and the apical anterior, inferior and lateral walls were thin, stiff and whitish. Nerve fibers in the apical inferior wall were atrophic and markedly fibrotic where MIBG uptake was most reduced. Nerve fibers in the septum were normal where MIBG uptake had remained normal. The histologic findings correspond with the findings on the MIBG image. MIBG imaging may detect cardiac sympathetic denervation in doxorubicin-induced cardiomyopathy before cardiac symptoms are manifest and cardiac function deteriorates.

Simultaneous analysis of mucosal and submucosal hemodynamics using infrared electronic endoscopy: effects of intraluminal acid on ulcer scars

BACKGROUND AND STUDY AIMS

This report describes the use of an infrared electronic endoscope for the assessment of gastric mucosal and submucosal hemodynamics in ulcer scars.

METHODS

The experimental ulcer scars were induced by acetic acid injection in five anesthetized dogs. Indices of mucosal hemoglobin content (IHb) and its oxygenation (ISO2) were calculated from reflectance spectra of the mucosa at 569, 577, 586, and 650 nm, which were obtained through an optic probe. The gastric submucosal vascular diameter was assessed by comparison with a reference wire under infrared endoscopic observation.

RESULTS

The index of mucosal hemoglobin content measured by reflectance spectrophotometry was significantly higher at the ulcer scars than in the intact mucosa before the ulcer induction. Intraluminal administration of 0.2 N hydrochloric acid lowered IHb and ISO2 only at the ulcer scars. The diameters of the gastric submucosal veins beneath the ulcer scars decreased markedly after the acid administration.

CONCLUSION

The results suggest abnormal responses of gastric mucosal and submucosal circulation at ulcer scars to intraluminal acid. Infrared electronic endoscopy is therefore a useful tool for the simultaneous analysis of mucosal and submucosal circulation in the stomach.

Differences in motor control in the bronchus and extrathoracic trachea

The motor control of the bronchus and extrathoracic trachea was evaluated by continuously measuring bronchial diameter and tracheal muscle tension as well as phrenic nerve activity in decerebrated, paralyzed, artificially ventilated dogs. Spontaneous rhythmic changes in bronchial diameter and tracheal muscle tension occurred in phase with phrenic burst during mechanical ventilation and during apnea induced by disconnecting the ventilator. There was a small but consistent difference in the timing of their rhythmic activities; bronchial constriction started at mid-inspiration, whereas tracheal contraction began just prior to the end of inspiration. Both were active in the post-inspiratory phase. Both hypercapnia and apnea caused an enhanced rhythmic constriction of the bronchus, while evoking a tonic contraction of the trachea. Intermittent electric stimulation of the efferent vagus nerves revealed that repetitive stimulation with a short intermission was necessary to evoke a sustained constriction of the bronchus, and that the bronchus could maintain the sustained constriction only transiently. These results indicate that the motor control of the bronchus and extrathoracic trachea are distinct. The central nervous system may contribute to the difference in timing of the contraction between tracheal and bronchial smooth muscle. However, the difference in response to electric stimulation of the nervus vagus may be attributed to the peripheral neuromuscular system.

The influence of surgical insults on restenosis after transluminal balloon angioplasty

The influences of atherogenic response on restenosis after transluminal balloon angioplasty and the anastomosis of arterial reconstruction were investigated. Iliac transluminal balloon angioplasty was performed on 81 consecutive patients at 86 sites, between January, 1987 and December, 1992. A balloon angioplasty alone was performed in 58 patients at 60 sites, while distal revascularization was performed in 23 patients on 26 limbs, in association with the angioplasty. An improvement in the inflow of the distal grafts was achieved in 22 of these 23 patients in 26 limbs. The combined distal revascularization included 21 femoropopliteal bypasses, 3 femorofemoral bypasses, and 2 thromboendarterectomies at the profunda femoris arteries. A reduction in the luminal diameter after the balloon angioplasty was determined by means of follow-up arteriograms which showed no obvious progression of the restenosis at the angioplasty sites even when neointimal hyperplasia had developed at the anastomosis of the arterial reconstruction. The accumulative graft patency rate of the combined distal revascularization did not differ significantly from that of femoropopliteal reconstructions alone during the same study period. This study demonstrated that concomitant surgical insults do not have a detrimental effect on restenoses at angioplasty sites.

Gene targeting with a replication-defective adenovirus vector

Wide application of the gene-targeting technique has been hampered by its low level of efficiency. A replication-defective adenovirus vector was used for efficient delivery of donor DNA in order to bypass this problem. Homologous recombination was selected between a donor neo gene inserted in the adenovirus vector and a target mutant neo gene on a nuclear papillomavirus plasmid. These recombinant adenoviruses allowed gene transfer to 100% of the treated cells without impairing their viability. Homologous recombinants were obtained at a level of frequency much higher than that obtained by electroporation or a calcium phosphate procedure. The structure of the recombinants was analyzed in detail after recovery in an Escherichia coli strain. All of the recombinants examined had experienced a precise correction of the mutant neo gene. Some of them had a nonhomologous rearrangement of their sequences as well. One type of nonhomologous recombination took place at the end of the donor-target homology. The vector adenovirus DNA was inserted into some of the products obtained at a high multiplicity of infection. The insertion was at the end of the donor-target homology with a concomitant insertion of a 10-bp-long filler sequence in one of the recombinants. The possible relationship between these rearrangements and the homologous recombination is discussed. These results demonstrate the applicability of adenovirus-mediated gene delivery in gene targeting and gene therapy.

Emergence of in vitro resistance to fluoroquinolones in Neisseria gonorrhoeae isolated in Japan

To investigate emerging fluoroquinolone resistance in Neisseria gonorrhoeae isolated in Japan, we compared the in vitro antimicrobial susceptibilities of 79 gonococcal isolates from 1992 through 1993 to 14 fluoroquinolones and 14 other antibiotics with those of 27 isolates from between 1981 and 1984. The MICs at which 90% of the isolates were inhibited by nine fluroquinolones, including norfloxacin, enoxacin, ofloxacin, ciprofloxacin, tosufloxacin, lomefloxacin, fleroxacin, levofloxacin, and sparfloxacin, for isolates from 1992 to 1993 were 8- or 16-fold higher than those for isolates from 1981 to 1984. Furthermore, the MICs at which 90% of the isolates were inhibited by five fluroquinolones, including OPC-17116, T-3761, DU-6859a, AM-1155, and Q-35, that have recently been synthesized but have not yet been introduced for clinical use in Japan for isolates from 1992 to 1993 were also 2- to 16-fold higher than those for isolates from 1981 to 1984. The gonococcal isolates from 1992 to 1993 showed no significant decreases in susceptibility to beta-lactams, tetracyclines, macrolides, and spectinomycin, compared with those for isolates from 1981 to 1984. Our data indicate that the incidence of gonococcal strains with decreased susceptibilities to fluoroquinolones is increasing in Japan.

Effects of age and obesity on glycated haemoglobin and 1,5-anhydroglucitol in screening for type 2 diabetes mellitus

The diagnostic accuracy of glycated haemoglobin (HbA1c) and 1,5-anhydroglucitol (AG) and their association with age and obesity in the community screening for Type 2 diabetes were investigated. HbA1c and AG were measured in 368 subjects at the time of an oral glucose tolerance test (OGTT) based on WHO criteria. The impact of age and obesity on the probability of diabetes was evaluated by multivariate logistic regression analysis. Receiver operating characteristic (ROC) analysis was used to assess diagnostic accuracy of each method. The areas under ROC curves were compared for subjects aged 30-59 and 60-82 years. In the logistic analysis, age was associated with the probability of diabetes, while body mass index did not contribute to the model. The paired ROC analyses indicated that HbA1c was superior to AG only in the younger subjects. When the areas for two age groups were compared, both HbA1c and AG performed better in the younger than older subjects. We conclude that for the younger subjects, HbA1c value is highly sensitive (100.0%) and specific (90.4%) and is helpful for the diagnosis of Type 2 diabetes. On the other hand for the older subjects, both HbA1c and AG are poor screening tests in reference to the OGTT standard.

[B/F non-separative method]

In homogeneous enzyme immunoassay without requirement of separation of free and bound label, the concentration of substances in samples can be detected by measurement of enzyme activity in the mixtures of samples (antigen) and reagents (labeled antigens antibodies, and enzyme substrates). The methods described herein offer the virtues of simplicity and rapidity by use of general-purpose automated clinical analyzer. The concentrations of some drugs, hormones, antibiotics, and very small amount of certain proteins are now detected by the routine examination in these techniques employing commercial diagnostic kits offered by several companies. In this manuscript, we attempted to give an overview of the principle of various methods by use of commercial diagnostic kit applied in routine clinical examinations.

[Effects of azithromycin on fecal flora of healthy adult volunteers]

New macrolide antibiotic, azithromycin (AZM), was administered to six healthy male volunteers and its effects on their intestinal microflora were investigated. Each volunteer was given 500 mg of AZM orally, once a day for 3 consecutive days. Stool samples were obtained from them prior to the medication and 1, 7, 14 and 28 days after the third day the medication. A slight decrease in the total aerobic bacterial count was observed. Also, several species of anaerobic bacteria showed slight decreases through the 14th day post medication. Individual variances were observed, however. A marked decrease in the number of Bifidobacterium was found for each of the volunteers. Clostridium difficile was detected from one of the volunteers on the 28th day post medication without diarrhea related symptoms.

Saiboku-To, a herbal extract mixture, selectively inhibits 5-lipoxygenase activity in leukotriene synthesis in rat basophilic leukemia-1 cells

Saiboku-To, a mixture of extracts from 10 medicinal herbs, has been used for the treatment of bronchial asthma in Japan. Inhibitory action of this drug on arachidonate 5-lipoxygenase (5-LO) metabolism in rat basophilic leukemia cells (RBL-1 cells) was examined. Saiboku-To significantly inhibited calcium ionophore-stimulated synthesis of cysteinyl leukotrienes (cLTs) and leukotriene B4 (LTB4). Inhibition appeared 10 min after addition of the substance and reached a maximal value after 3 h. Saiboku-To did not inhibit the release of [3H]arachidonic acid (AA) from cell membrane by calcium ionophore stimulation, or the production of cLTs and LTB4 when LTA4-free acid was used as the substrate. However, it significantly inhibited the production of cLTs and LTB4 when free AA was used as the substrate. The production of thromboxane A2 (TXA2). a cyclooxygenase metabolite, was not inhibited when AA was used as the substrate in cell free study. These results indicate that Saiboku-To selectively inhibits 5-LO activity in the metabolic pathway of AA.

The proliferative activity in oral epithelial dysplasia analyzed by proliferating cell nuclear antigen immunostaining and argyrophilic nucleolar organizer region staining

The proliferative activity of leukoplakia without dysplastic change (LP), epithelial dysplasia (ED), and squamous cell carcinoma (SCC) in the oral mucosa was examined by means of proliferating cell nuclear antigen (PCNA) immunostaining, silver-binding argyrophilic nucleolar organizer region (AgNOR) staining, and the frequency of mitotic figures. Significant differences in the labeling index of PCNA immunostaining (PI) and mitotic index (MI) were noted between LP and ED and between ED and SCC. The mean numbers of AgNORs (AI) significantly differed between ED and SCC. There was a significant positive correlation between PI and MI in samples of ED. However, there was no significant correlation between AI and other indexes. The number and the distribution of PCNA-positive cells in ED varied among samples. Five samples with higher PI and MI indexes than the mean values were selected from those of dysplasia based on the correlation between PI and MI. Their histological features symptomatic of oral ED as defined by the World Health Organization (WHO) Collaborating Centre in 1978, were investigated and compared with 10 samples with lower indexes. Histological findings, such as "loss of polarity of the basal cells," "an increased nuclear-cytoplasmic ratio," "cellular pleomorphism," and "enlarged nucleoli," were significant histological features of these five samples. This study showed that the four histological components described previously and the increased number of mitotic figures used as the index of proliferating activity were the main histological components related to severe ED of oral mucosa. They will provide a useful means of deciding the histopathological grade of oral ED.

[Measurement of serum TSH receptor antibodies in thyroid patients using TRAb Dade kits]

TRAb Dade kit is a radioreceptor assay that detects autoantibodies in serum of patients with thyroid diseases which interfere with the binding of 125I labeled TSH to its receptor. In this paper we examined the basic and clinical usefulness of newly developed TRAb assay kits. The intra and inter assay coefficients of variation were 7.9% and 8.4%, respectively. There was no significant effect of temperature and incubation time on TRAb values. The influence of conjugated, unconjugated bilirubin, hemoglobin and turbidity was not so significant on TRAb values. TRAb values in serum of 68 untreated Graves' disease were above the normal range, but most (78%) treated Graves' patients who became euthyroid after receiving antithyroid drug, showed the normal range. In patients with chronic renal failure TRAb values were also within the normal range. A significant correlation (y = 1.0x-0.88, r = 0.95) was observed between this TRAb kit and TRAb Cosmic values in various thyroid conditions. This new assay for TRAb was simple, rapid and reproducible. The measurement of serum TRAb values was useful for the evaluation of physiological and pathological function and seemed to be helpful in the management of patients with thyroid disease.

[Relationship between proliferative activity, and tissue differentiation and invasive mode in human oral squamous cell and colorectal carcinomas analysed by PCNA immunostaining]

The proliferative activity of carcinoma cells is generally considered to relate to the degree of the malignancy of carcinoma tissues. In this study, the proliferative activity at the tumor-stromal border was studied in 17 cases of oral squamous cell carcinoma (OSCC) and in 30 cases of colorectal adenocarcinoma (CAC) by means of proliferating cell nuclear antigen (PCNA) immunostaining, to evaluate the correlation between proliferative activity and tissue differentiation or invasive mode at the tumor-stromal border. No statistical difference was detected between the PCNA labelling index (PI) and the tissue differentiation of both OSCC and CAC. A significant difference was demonstrated between PI and invasive mode in OSCC, suggesting that the invasive mode at the tumor-stromal border relate to the degree of the malignancy of carcinoma tissues. However, no significance was found between PI and invasive mode of CAC. In addition, no difference of PI was demonstrated between tissue differentiation or invasive mode, and vascular invasion or lymph node metastasis. Therefore, it seems likely that the invasive mode at the tumor-stromal border in CAC also has no significance in deciding the degree of the malignancy of carcinoma tissues.

Effect of combination therapy with OK432 and recombinant human interferon-alpha A/D on atrial natriuretic peptide gene expression in mice with viral myocarditis

The effects of combination therapy with the immunomodulators OK432 (derived from the Su strain of Streptococcus pyogenes A3; 1 unit corresponds to 0.1 mg of dried streptococci dissolved in 0.1 ml of saline) and human recombinant interferon-alpha A/D (IFN) on cardiac atrial natriuretic peptide (ANP) gene expression and myocardial hypertrophy were examined in a murine model of viral myocarditis with congestive heart failure. Therapy was started 24 h after inoculation with encephalomyocarditis virus and was continued for 14 days. The plasma ANP concentration in untreated infected mice was significantly (P < .01) increased on day 10 (115 +/- 48 pg/ml) and day 30 (43 +/- 22 pg/ml) after inoculation relative to that in uninfected controls (5 +/- 4 pg/ml), whereas plasma ANP levels in treated mice were significantly (P < .01) reduced on day 10 (14 +/- 13 pg/ml) and day 30 (11 +/- 9 pg/ml) in comparison with untreated infected mice. The atrial and ventricular ANP messenger RNA (mRNA) concentrations in untreated mice showed increases of approximately 1.4- and 29.3-fold, respectively, on day 10 and increases of 1.8- and 34-fold, respectively, on day 30 compared with the concentration in uninfected controls. Combined OK432 and IFN significantly (P < .01) reduced the increase in ANP mRNA concentration in ventricles to 6.0- and 6.7-fold on days 10 and 30, respectively. Neither OK432 nor IFN monotherapy reduced the ANP mRNA concentrations in atria and ventricles compared with those in untreated controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Polyarginine and eosinophil-derived major basic protein increase microvascular permeability independently of histamine or nitric oxide release

We tested the hypothesis that cationic peptides (polyarginine; poly-argn) and eosinophil-derived major basic protein (MaBP) increase permeability by stimulating the release of histamine and/or nitric oxide. We used intravital microscopy, clearance, and integrated optical intensity (IOI), using FITC-dextran 150 (FITC-dx 150) as a tracer, to evaluate changes in microvascular permeability in the hamster cheek pouch. Poly-argn at 1 microM (topical) increased the clearance of FITC-dx 150 from 610 to 3240 nl/60 min/g. In contrast, 1 microM polyglutamic acid (poly-glun; and anionic peptide) did not affect the clearance of FITC-dx 150 (605 nl/60 min/g). At 0.5 and 1.0 nM, poly-argn increased the clearance of FITC-dx 150 from 610 to 1722 and 2396 nl/60 min/g (P < 0.05). Similarly, 0.5 nM MaBP increased clearance from 591 +/- 38 to 1967 +/- 168 nl/60 min/g. L-NAME at 10(-4) M did not prevent the 0.5 nM MaBP-induced elevation in clearance (1784 +/- 350). Poly-argn at 1 nM increased net mean IOI by 21.5 +/- 7.2 units. This elevation was not inhibited by topical 10(-4) M L-NMMA (27.5 +/- 8.4). Using 0.5 nM poly-argn as agonist, we assayed suffusate samples for their histamine concentration using a competitive enzyme immunoassay and found no detectable histamine. Pyrilamine, an H1 antagonist, did not inhibit the 0.5 nM poly-argn-induced elevation in clearance of FITC-dx 150. We conclude that (1) cationic peptides and MaBP increase microvascular permeability and (2) the increase in microvascular permeability produced by low concentrations of poly-argn and by MaBP is independent of the release of histamine and does not require nitric oxide.

Immunohistochemical study on the immunocompetent cells of the pulp in human non-carious and carious teeth

The condition of the pulp tissue was classified into seven groups according to the depth of carious lesions from stage (S) 0 (non-carious teeth) to S6 (exposed pulp). A substantial change in the infiltration of immunocompetent cells occurred between S3 and S4; all types were markedly increased in S4 as compared to S3, with a remarkable increase in the number of helper T lymphocytes, B-lineage cells, neutrophils and macrophages. Therefore, the pulpal immune reaction to carious stimuli could be classified into early (S1-S3) and advanced phases (S4-S6). In the early phase a cellular immunoresponse would be induced by T-lineage cells, and in the advanced phase the humoral immunoresponse is furthered by B-lineage cells concomitant with the destruction of pulp tissue by proteolytic enzymes released from infiltrating neutrophils and macrophages. Human dental pulp is thus equipped with a functional immune response that is sufficient as a biodefensive mechanism. Dental caries should be treated before S4.

Comparative effects of losartan, captopril, and enalapril on murine acute myocarditis due to encephalomyocarditis virus

Losartan, a recently developed nonpeptide angiotensin II (AII) receptor antagonist, was orally administered for 14 days to mice with viral myocarditis, beginning 7 days after encephalomyocarditis virus inoculation. The angiotensin-converting enzyme inhibitors (ACEI) captopril and enalapril were also administered in the same manner to compare the therapeutic effects of these three drugs on the degree of myocarditis, acute heart failure, and left ventricular (LV) hypertrophy. Heart weight and the heart weight/body weight ratio were reduced by losartan (60 mg/kg/day) and captopril (7.5 mg/kg/day), but not by enalapril (1 mg/kg/day). LV wall thickness and cavity dimension were decreased in the losartan and captopril groups. Captopril reduced both myocardial necrosis and inflammation, whereas enalapril reduced myocardial necrosis but not inflammation. However, none of the studied losartan doses (1.2, 12, 60 mg/kg/day) influenced myocardial necrosis and inflammation resulting from viral infection. Thus, specific blockade of AII is beneficial in congestive heart failure (CHF) and LV hypertrophy but is not effective in viral-evoked inflammation and injury.

Synergistic effects of tacrolimus and human interferon-alpha A/D in murine viral myocarditis

The effects of interferon-alpha A/D (IFN) therapy in combination with various immunosuppressants were investigated in a murine model of viral myocarditis. Viral infection is an important cause of morbidity in immunocompromised hosts and transplant recipients. Human IFN therapy reduces viral replication, reducing the virus-induced myocardial destruction. Groups consisting of 25 C3H/He mice received i.p. injections of prednisolone, azathioprine, 15-deoxyspergualin, cyclosporine or tacrolimus (FK506), for 16 days beginning 2 days before inoculation with 500 plaque-forming units of encephalomyocarditis virus (EMCV). IFN, 10(4) U/g daily, was administered i.p. alone or in combination with immunosuppressants to separate groups of mice beginning on the day of viral inoculation. Animals were sacrificed at random at 4 or 10 days after inoculation with EMCV. The survival rate was significantly higher in mice treated with azathioprine, 15-deoxyspergualin, cyclosporine or FK506 in combination with IFN than in infected controls (P < .01) and was similar to the rate in the IFN monotherapy group. Survival in mice treated with prednisolone resembled that in infected controls and was significantly lower than in mice treated with IFN (P < .01). Heart weight was lower and cellular infiltration in the myocardium was reduced in mice treated with both FK506 and IFN compared with mice given IFN monotherapy. The results suggest that the effect of IFN therapy in viral myocarditis differs depending on which immunosuppressants is used. The findings suggest that the combination of FK506 and IFN may have beneficial effects in hosts with viral myocarditis by reducing cellular infiltration of heart.

[Heterogeneity of lipopolysaccharide chain size of Pseudomonas aeruginosa isolated from different clinical sources--with reference to gentamicin-susceptibility and serotype]

Lipopolysaccharide (LPS) compositions of P. aeruginosa isolated from from clinical sources such as blood, urine, pus, sputum, and feces were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and aminoglycoside-susceptibility and serotype of these isolates were investigated in this study. Fifty-nine isolates tested were divided into three groups according to the difference in their LPS compositions; 35 strains with the long-LPS chain (B-band LPS), 14 strains with the short chain (A-band LPS) and 10 LPS-deficient strains. The relationship between the LPS compositions and their sources of 59 strains were investigated. The majority of clinical isolates (12 of the 13 strains) from the blood samples possessed the long-LPS chain (B-band LPS) and the remaining possessed the short-LPS chain (A-band LPS). About 67% each of the isolates from urine and feces possessed the long-LPS chain, and the minor part of both groups possessed the short-LPS chain. In isolates from both sputum and pus samples, the long- and short-LPS chains were found at almost the same rate, and the LPS-deficient isolates were found in the sputum samples at a considerably high rate of 42%. The 19 of the 35 isolates with the long-LPS chain were susceptible to gentamicin (54%) and 12 isolates were resistant (34%). On the other hand, the 14 isolates with the short chain were divided roughly into three groups, gentamicin-resistant, and -susceptible groups and intermediate groups. It was also notable that 7 of the 10 LPS-deficient isolates were resistant to gentamicin.(ABSTRACT TRUNCATED AT 250 WORDS)