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In order to investigate the role of the cytokine-induced neutrophil chemoattractant (CINC) in chronic bronchopulmonary infection, we developed a rat model of bronchopulmonary infection with Pseudomonas aeruginosa by using the agar bead method, and determined the kinetics of bacterial and cell number, as well as the concentrations of CINC-1, CINC-2, and CINC-3 in bronchoalveolar lavage (BAL) fluids in this model. The bacterial number in the lung rapidly increased from days 1 to 4, and declined 14 days after challenge. Neutrophil number in BAL fluid increased up to one day after challenge, and then slowly decreased during 14 days post-challenge. Among the CINCs, the local production of CINC-2 alpha sharply increased at day 1 and then decreased until day 4 post-challenge, while the local production of CINC-1 slightly increased at day 1 post-challenge. Neither CINC-2 beta nor CINC-3 were detected during the entire course of the infection. Increased CINC-2 mRNA expression in the lung tissue after challenge was associated with CINC-2 alpha production in BAL fluid. Moreover, an immunohistochemical study demonstrated the localization of CINC-1 and CINC-2 alpha primarily in alveolar macrophages and, to a much lesser extent, in bronchial epithelium of infected lung tissues, whereas CINC-2 beta and CINC-3 were not detected. When anti-CINC-1 or anti-CINC-2 alpha polyclonal antibodies were used for neutralizing neutrophil chemotactic activities in BAL fluids, the anti-CINC-2 alpha antibody inhibited 70% of the chemotactic activity in BAL fluids from infected rats at day 1 after challenge. No inhibition was observed by anti-CINC-1 antibody. These data indicate that CINC-2 alpha, which is produced by alveolar macrophages and bronchial epithelial cells, plays a pivotal role in neutrophil accumulation in the airway of a rat model of chronic bronchopulmonary infection with P. aeruginosa., (Copyright 2000 Academic Press.)

Using five diagnostic markers, we compared the types of 72 strains of methicillin-resistant Staphylococcus aureus (MRSA) isolated simultaneously from the nasal cavity, pharynx, and sputum from 24 patients. Almost identical MRSA types had colonized the nasal cavity and sputum from the same patient for 21 (88%) of the patients. We speculate that most MRSA organisms isolated in sputum are derived from the nasal cavity, while a few are derived from the pharynx.

CXCR4, a coreceptor for T cell (T)-tropic HIV-1, is preferentially expressed on naive T cells, whereas CCR5, a coreceptor for macrophage (M)-tropic HIV-1, is preferentially expressed on previously activated memory T cells and the Th1 subset of CD4+ T cells. CCR4 is preferentially expressed on the Th2 subset of CD4+ T cells. A cross-sectional flow cytometry study was conducted to evaluate the expression of CXCR4, CCR5, and CCR4 on the peripheral blood CD4+ T cells from African HIV-1-infected and uninfected Ugandan adults. The plasma viral load in HIV-1-infected individuals was also examined. Upregulation of CCR4 and CCR5 expression but no decrease in CXCR4 expression on CD4+ T cells were obtained in peripheral blood from African adults with progression of the disease. Plasma HIV-1 viremia significantly and inversely correlated with the peripheral CD4+ T cell count but did not correlate with the degree of CCR4 and CCR5 expression on the peripheral CD4+ T cells in HIV-1-infected individuals. Our present data suggest an increase in percentage of activated memory CD4+ T cells in the advanced stage of HIV-1 infection among African adults. There was no evidence of a Th1 to Th2 shift in terms of chemokine receptor expression profile with advancing disease in the peripheral blood of these subjects.

To characterize the clinical features and etiology of recently encountered cases of community-acquired pneumonia (CAP), we carried out a hospital-based retrospective study of 120 episodes of CAP (115 patients) at Tagami Hospital, Nagasaki City between 1994 and 1997. We identified the causative pathogens in 55 episodes (50 patients) by sputum Gram stain and quantitative culture, for a determination rate of 45.8%. Streptococcus pneumoniae (17 episodes) and Haemophilus influenzae (15 episodes) were the primary causative organisms. It is noteworthy that two major nosocomial pathogens, Pseudomonas aeruginosa (P. aeruginosa; 5 episodes) and Methicillin-resistant Staphylococcus aureus (MRSA; 2 episodes), were also identified as causative agents of CAP. These two pathogens were isolated from patients with severe underlying diseases and patients who had been repeatedly hospitalized. The incidence of CAP due to P. aeruginosa and MRSA is increasing because patients with respiratory colonization by these nosocomial pathogens are often followed up on an outpatient basis.

Attachment of bacteria to host cells is the initial step in the pathogenesis of infection. Several factors, such as hydrophobicity, surface electric charge, and van der Waals force, are considered to be responsible for the attachment step. However, it is not clear why bacteria and epithelial cells, both of which possess a negative surface charge, do not repel one another. In the present study, we used Moraxella catarrhalis and pharyngeal epithelial cells to study the surface charges of structures involved in the attachment. By atomic force microscopy (AFM) equipped with surface potential spectroscopy, it was found that the cell surface microplicae have a positive charge of 30.1+/-3.6 mV (mean+/-SE). The depressions between the microplicae have a negative surface charge of 43.5+/-4.0 mV. Using cationic ferritin and electron microscopy (EM) we confirmed that the depressions between the microplicae have a negative charge. By AFM and by using cationic ferritin with EM, it was found that the net surface charge of the bacterial cells is negative. By both AFM and EM, it was found that the bacterial cells attach to the microplicae of the pharyngeal epithelial cell. Our work confirmed the general belief that both kinds of cells do have a net negative charge. We conclude that there are positively and negatively charged domains on the surface of human pharyngeal epithelial cells. M. catarrhalis evidently attaches to the positively charged domain (i.e. microplicae) of pharyngeal epithelial cells., (Copyright 2000 Academic Press.)

Objective: This study aimed to determine the clinical difference of pneumonia between penicillin-resistant and penicillin-sensitive Streptococcus pneumoniae., Methodology: Forty-nine cases in 46 patients of pneumococcal pneumonia were studied from December 1992 to May 1997. There were 24 cases (in 22 patients) of penicillin-resistant pneumococci (PRSP) pneumonia which were compared with 25 cases (in 24 patients) with penicillin-sensitive pneumococci (PSSP)., Results: Both the mean age and the underlying disease states did not differ between the two groups. However, hospital-acquired pneumonia and previous use of antibiotics were observed in eight (33.3%) and 12 (50.0%) patients in PRSP compared with three (12.0%) and two (8.0%) in PSSP, respectively. The clinical efficacy rate and bacteriological eradication rates were 87.5 and 87.5% in PRSP compared with 87.5 and 87.0% in PSSP, respectively. Minimum inhibitory concentration (MIC) of antibiotics against 30 pneumococcal isolates was examined, and 10 strains ranged from 0.10-0.78 microg/mL and five strains were more than 1.56 microg/mL against penicillin G, while the MIC showed higher resistance to other antibiotics except for the carbapenems. Serotyping of the isolates by antiserum revealed differences in the predominant types PRSP (19F) and PSSP (6A,9V) [corrected]., Conclusions: We must care for not only community-acquired infection but also nosocomial transmission of PRSP pneumonia. Most patients with infections due to PRSP tended to have a milder illness with a good outcome (no patient died). As such it appears that empiric therapy for pneumococcal pneumonia does not require modification from what is recommended at present. However, in patients with infection due to highly resistant strains, and who are not responding to conventional therapy should have their treatment modified according to subsequent susceptibility testing.

Monocyte chemoattractant protein-1 (MCP-1), a chemoattractant for monocytes, is presumed to play a pivotal role in the recruitment and accumulation of monocytes in various diseases including pulmonary infections. We examined here whether or not Pseudomonas nitrite reductase (PNR), a recently identified IL-8 inducer in various respiratory cells, could stimulate human pulmonary type II epithelial-like cells (A549) to induce MCP-1 production. A time- and dose-dependent induction of MCP-1 protein synthesis associated with an increase of MCP-1 mRNA expression by A549 cells was observed in response to PNR. New protein translation was not required for PNR-mediated MCP-1 mRNA expression in the same cells. When anti-human MCP-1 monoclonal antibody was used for neutralizing of monocyte chemotactic factor (MCF) activities in the culture supernatants of these cells stimulated with PNR, significant reductions of MCF activities (the mean reduction rate; 49-59%, P<0. 05) were observed. These data suggest that PNR may contribute to monocyte migration, through inducing pulmonary epithelial cell-derived MCP-1 production in the airway of patients with pneumonia due to P. aeruginosa., (Copyright 2000 Academic Press.)

Helicobacter pylori is an etiological agent of gastritis, peptic ulcer, and gastric cancer. Human beta-defensin-2 (hBD-2) is an antimicrobial peptide which belongs to one of the most important host defense systems against bacterial infection in several epithelial tissues. We studied the effect of H. pylori on the expression of hBD-2 mRNA in MKN45 gastric mucosal cells. H. pylori, but not culture filtrate, increased the hBD-2 mRNA level in MKN45 cells; the inductive effect of H. pylori was not detected with Intestine 407 cells. Among H. pylori strains, strain OHPC0002, which lacks a cag Pathogenicity Island (PAI), did not induce hBD-2 mRNA in MKN45 cells. These results suggested that H. pylori cag PAI is critical for the induction of hBD-2 mRNA in MKN45 cells. Exposure of MKN45 cells to Salmonella typhimurium, S. enteritidis, S. typhi, and S. dublin, but not Escherichia coli ML35, also resulted in induction of hBD-2 mRNA., (Copyright 1999 Academic Press.)

Moraxella catarrhalis is recognised as a major pathogen in chronic respiratory diseases. Patients with pneumoconiosis have repeated respiratory infections, and the control is very important for good prognosis. From 1988 to 1993, fifty strains of Moraxella catarrhalis were obtained from 9 patients with pneumoconiosis attended at Nagasaki Rosai Hospital. Restriction enzyme analysis of chromosomal DNA by Hind III. Hae III, Cla I was performed on 50 strains of M. catarrhalis. Twelve strains (56%) out of 23 isolates with interval of less than 5 months had identical bacterial restriction endonuclease digestion patterns with three different enzymes, and all isolates with interval more than 6 months had different patterns. Tweny out of 13 episodes by the same strains occurred during 3 months. The acquisition and clearance of M. catarrhalis from the respiratory tract is a dynamic process.

We have recently reported that nitrite reductase, a bifunctional enzyme located in the periplasmic space of Pseudomonas aeruginosa, could induce interleukin-8 (IL-8) generation in a variety of respiratory cells, including bronchial epithelial cells (K. Oishi et al. Infect. Immun. 65:2648-2655, 1997). In this report, we examined the mode of nitrite reductase (PNR) release from a serum-sensitive strain of live P. aeruginosa cells during in vitro treatment with four different antimicrobial agents or human complement. Bacterial killing of P. aeruginosa by antimicrobial agents induced PNR release and mediated IL-8 production in human bronchial epithelial (BET-1A) cells. Among these agents, imipenem demonstrated rapid killing of P. aeruginosa as well as rapid release of PNR and resulted in the highest IL-8 production. Complement-mediated killing of P. aeruginosa was also associated with PNR release and enhanced IL-8 production. The immunoprecipitates of the aliquots of bacterial culture containing imipenem or complement with anti-PNR immunoglobulin G (IgG) induced twofold-higher IL-8 production than did the immunoprecipitates of the aliquots of bacterial culture with a control IgG. These pieces of evidence confirmed that PNR released in the aliquots of bacterial culture was responsible for IL-8 production in the BET-1A cells. Furthermore, the culture supernatants of the BET-1A cells stimulated with aliquots of bacterial culture containing antimicrobial agents or complement similarly mediated neutrophil migration in vitro. These data support the possibility that a potent inducer of IL-8, PNR, could be released from P. aeruginosa after exposure to antimicrobial agents or complement and contributes to neutrophil migration in the airways during bronchopulmonary infections with P. aeruginosa.

Cutaneous Kaposi's sarcoma (KS) is a well-known complication of the acquired immunodeficiency syndrome. KS in the internal organs, however, is rare in Japan. We present here a 33-years-old Japanese homosexual man who had AIDS complicated with cytomegalovirus (CMV) infection and KS. He was found to be HIV-seropositive, when he was 31-years-old. He visited our hospital in June 1996 because of high fever. The peripheral blood CD4+ lymphocyte counts were 2 per cubic millimeter, and CMV antigenemia was noted (p65 antigen positive cells; 240/50,000 white blood cells). Thereafter he was successfully treated with parental ganciclovir. On admission, some brown-colored flat nodules were found on the skin, and the diagnosis of KS was made by skin biopsy. We administrated human chorionic gonadotropin (hCG) for the treatment of KS, but had no clinical response. In September 1996, he complained of severe cough, shortness of breath, and vomiting. A chest radiogram showed nodular lesions and pleural effusion in bilateral lungs. A computed tomography of his chest also revealed nodular and linear densities distributed along the bronchovascular bundles. The ultrasonic examination of his abdomen revealed a duodenal nodule. Both nodules in the lungs and duodenum were proved to be KS based on the autopsy findings. Intranuclear inclusionbodies pathognomonic for CMV infections were detected in the stomach and the colon.

A 37-year-old Japanese male was admitted to Nagasaki University Hospital with abrupt onset of biphasic fever, general malaise and myalgia 9 days after coming back to Japan from Manila. He developed a rubella like erythematous rash 3 days after admission and purpuric eruption one week after admission. A biopsied specimen from the purpura revealed lymphocytic vasculitis with T cell dominance and without immunoglobulin or complement deposition around the blood vessels. RT-PCR analysis on peripheral blood mononuclear cells using dengue virus specific primers confirmed the diagnosis of type 3 dengue fever. PCR analysis using virus specific primers is a rapid and valuable method for making a correct diagnosis of dengue fever.

Interleukin-8 (IL-8) participates in the generation of dense neutrophil accumulations in bronchopulmonary infections caused by Pseudomonas aeruginosa (P. aeruginosa). We have recently reported that nitrite reductase, a bifunctional enzyme located in the periplasmic space of P. aeruginosa, induces IL-8 generation in bronchial epithelial cells (K. Oishi et al. Infect. Immun. 65: 2648-2655, 1997). We examined whether or not Pseudomonas nitrite reductase (PNR) could also stimulate human alveolar macrophages (AM) and pulmonary type II epithelial-like cells (A549) to induce IL-8 production and mRNA expression as well as the production of TNF alpha and IL-1beta. We demonstrated a time- and dose-dependent IL-8 protein synthesis and IL-8 mRNA expression, but no TNF alpha or IL-1beta production, by A549 cells in response to PNR. New protein translation was not required for PNR-mediated IL-8 mRNA expression in the same cells. Furthermore, simultaneous stimulation of PNR with serial doses of TNF alpha or IL-1beta resulted in additive IL-8 production in A549 cells. In adherent AM, PNR enhanced IL-8 protein synthesis and IL-8 mRNA expression in a time-dependent fashion. PNR similarly induced a time-dependent production of TNF alpha and IL-1beta by human adherent AM. Neutralization of TNF alpha or IL-1beta did not influence the levels of IL-8 production in adherent AM culture. We also evaluated whether the culture supernatants of the A549 cells or AM stimulated with PNR could similarly mediate neutrophil migration in vitro. When anti-human IL-8 immunoglobulin G was used for neutralizing neutrophil chemotactic factor (NCF) activities in the culture supernatants of these cells stimulated with 5 microg/ml of PNR, the mean percent reduction of NCF activities were 49-59% in A549 cells and 24-34% in AM. Our present data support that PNR directly stimulates AM and pulmonary epithelial cells to produce IL-8. PNR also mediates neutrophil migration, in part, through IL-8 production from AM and pulmonary epithelial cells. These data suggest the contribution of PNR to the pathogenesis of bronchopulmonary infections due to P. aeruginosa.

We investigated the effects of two mucoregulating drugs, S-carboxymethylcysteine (S-CMC) and N-acetylcysteine (NAC), on the attachment of Moraxella catarrhalis (M. catarrhalis) to pharyngeal epithelial cells. The attachment of M. catarrhalis decreased (33-57%) significantly (P<0.01) in a dose-dependent manner in cells treated with mucoregulating drugs as compared to the control. There was a significant (P<0.01) decrease (35-45%) in the attachment of M. catarrhalis to pharyngeal cells after oral administration of S-CMC. By electron microscopic observation, it was found that there was a fine, granular, electron-dense, ruthenium red-positive layer on the surface of pharyngeal epithelial cells; this layer was absent on cell surfaces treated with mucoregulating drugs. Possibly, this layer contained the portion of M. catarrhalis receptor which is responsible for the attachment of this bacteria to pharyngeal epithelial cells. From the above results, it may be concluded that one of the mechanisms of mucoregulating drugs to decrease the episode of respiratory infections in patients with chronic respiratory diseases is by inhibiting the attachment of bacteria to the upper respiratory tract.

A 41-year-old male received acupuncture in the right shoulder for the sake of arthralgia. Three days after acupuncture he was admitted due to severe epigastralgia. Erythematous change and swelling were observed around the right shoulder. A study by magnetic resonance showed an increased signal intensity in a portion of the right subscapular muscle. Four hours after admission he became hypotensive. The erythematous and necrotic change in the right shoulder skin rapidly spread. Excisional debridement in the right lateral chest wall was immediately done. However, the patient died one day after admission despite administration of a high-dose ampicillin and other supportive therapies. Bacteriological and histological examinations confirmed severe streptococcal myositis. This is a case report of toxic shock-like syndrome probably caused by acupuncture.

We performed a randomized trial in which combination therapy with fluconazole and short-term flucytosine was compared with fluconazole monotherapy in 58 patients with AIDS-associated cryptococcal meningitis (CM). Thirty of these patients were randomized to receive combination therapy with fluconazole, 200 mg once a day for 2 months, and flucytosine, 150 mg/(kg.d) for the first 2 weeks, and 28 were randomized to receive monotherapy with fluconazole at the same dose for 2 months. Patients in both groups who survived for 2 months received fluconazole as maintenance therapy at a dose of 200 mg three times per week for 4 months. The combination therapy prevented death within 2 weeks and significantly increased the survival rate among these patients (32%) at 6 months over that among patients receiving monotherapy (12%) (P = .022). The combination therapy also resulted in a significant decrease in the severity of headache after 1 month of treatment, compared with monotherapy (P = .005). No serious adverse reactions were observed in patients receiving either regimen. These data indicate that treatment with fluconazole and short-term flucytosine is a cost-effective and safe regimen that improves the quality of life for patients with AIDS-associated CM in developing countries where human immunodeficiency virus is endemic.

Nontypable Haemophilus influenzae (NTHI) is one of the major pathogens of human respiratory infections and has the ability to attach to pharyngeal epithelial cells. We characterized the epithelial cell receptor to which NTHI bind. Neuraminidase pretreatment of pharyngeal epithelial cells resulted in a significant decrease in NTHI attachment, suggesting sialic acid as an important component of the receptor. The attachment was not decreased in NTHI pretreated with 1,000 microg/ml of fucose, N-acetyl-neuraminic acid, N-acetyl-glucosamine, N-acetyl-galactosamine, acetyl-salicylic acid and colominic acid. Only treatment with gangliosides D1a, D1b and D2 at a concentration of 12.5 microg/ml significantly decreased the attachment. On the other hand, treatment with gangliosides M1, M2, M3, D3, T1b and asialoganglioside M1 did not decrease the attachment of NTHI. Only ganglioside D2 inhibited the attachment significantly at a concentration of 12.5 ng/ml. Other isolates of NTHI showed a decrease in attachment after treatment with ganglioside D2. Treatment of cells with anti-human GD2 monoclonal antibody also decreased the attachment of NTHI in a dose-dependent manner. This study indicates that sialic acid glycoconjugate, GD2, is one of the receptors of NTHI on human pharyngeal epithelial cells.

We studied the clinical aspects of 25 patients (17 male, 8 female, median age 79.4 y.o.) whom MRSA was colonized in sputum from 1989 January to 1994 December. Main underlying diseases were 16 chronic bronchitis and 15 Cerebrovascular damage. Nineteen cases (76%) had catheters, for example 15 urinary tract catheters and 8 nasogastric tube. Twenty-two cases (88%) used previous antimicrobial agent. Fifteen cases (60%) were dead during previous period, and that 14 cases were dead because of respiratory failure within a year after MRSA was colonized in sputum. Nine cases (36%) were able to remove MRSA in sputum, but mortality rate was not different whether MRSA disappear or continue, MIC50 against MRSA (19 strains) were minocycline 12.5 micrograms/ml, arbekacin 6.25 micrograms/ml, vancomycin 0.78 microgram/ml and 16 cases (84.2%) were coagulase type II.

Three manifestations of pneumonia that are associated with influenza are well recognized: primary influenza viral pneumonia, secondary bacterial pneumonia and mixed viral and bacterial pneumonias. In an outbreak of influenza, primary influenza viral pneumonia has occurred predominantly. After a typical onset of influenza, there is a rapid progression of fever, cough and dyspnea. Physical examination and chest roentgenography reveal bilateral findings but no consolidation. A Gram stain of the sputum fails to reveal significant bacteria, and bacterial culture yield sparse growth of normal flora, where as viral cultures yield high titers of influenza virus. Such patients do not respond to antibiotics. Secondary bacterial pneumonia often produces a syndrome that is clinically distinguishable from that of primary viral pneumonia. Recrudescence of fever is associated with symptoms and signs of bacterial pneumonia such as cough, sputum production, and an area of consolidation detected on physical examination and chest roentgenography. Gram staining and the culture of sputum reveals a predominance of a bacterial pathogen, most often H. influenzae, S. pneumoniae, B. catarrhalis, or S. aureus. Such patients usually respond to specific antibiotic therapy. During an outbreak of influenza many cases an observed that do not clearly fit into either of the aforementioned categories. The disease is not relentlessly progressive, and yet the fever pattern may not be biphasic. These patients may have primary viral, secondary bacterial, or mixed viral and bacterial infection of the lung.

In the early 1980's methicillin-resistant Staphylococcus aureus (MRSA) was reported as a major pathogenic organism of geriatric hospital infection in Japan. At the same time in our geriatric wards, including 190 beds, MRSA infection was prevalent. In the early 1980's in our geriatric wards minocycline was one of the most sensitive antibiotics to MRSA isolated in our wards and used frequently against MRSA pneumonias and bacteremia. In the late 1980's resistant strains of MRSA to minocycline rapidly increased because vancomycin was not allowed to introduced for treatment of MRSA before 1991 in Japan. At the same period the predominant coagulase type changed from type II to type VII. To decrease minocycline-resistant strains to MRSA after 1987, use of minocycline was limited. Moreover since Oct. 1991 to decrease nosocomial infections some active preventive measures against hospital infection, including limited use of 2nd and 3rd cephems, were taken. In this study changing patterns of coagulase type of Staphylococcus aureus were discussed. At least 4 years was needed to find out that the predominant coagulase type changed from type VII to type II again in 1991. In this study about 22 antimicrobial agents MICs of 313 strains of Staphylococcus aureus isolated between March 1992 and June 1993 were determined and compared with the data of MICs before introduction of preventive measures. The pattern of susceptibility to MINO was in part improved. Thus the some sensitive strains of S. aureus were observed again in our geriatric wards. Interestingly indeed it took approximately 5 years to find out the emergence of sensitive strains to MINO since limitation of use of MINO in 1987.

A laboratory-based study of diagnosed bacterial meningitis in the national paediatric hospital identified 852 cases of meningitis in the 8-year period 1987-1994. There were 587 culture-positive cases, of which Haemophilus influenzae (47%) and Streptococcus pneumoniae (32%) accounted for 80%. H. influenzae showed a remarkable increase of 700% during the study period. Most of the H. influenzae cases (90%) occurred in the 1st 2 years of life. Analysis of culture-negative specimens by antigen detection in the last 2 years also revealed the predominance of H. influenzae (71.4%) and S. pneumoniae (22.4%). Typing of H. influenzae isolates during this time showed that 98% of the strains were type b. This retrospective hospital-based study indicated a pronounced increase in the incidence of H. influenzae meningitis and strongly supports the need for large-scale Hib vaccination for young children. However, such nationwide intervention will probably need to be based on a prospective on a prospective and population-based surveillance of H. influenzae infections.

In early 1980's methicillin-resistant Staphylococcus aureus (MRSA) was reported as a major pathogenic organism of geriatric hospital infection in Japan. At the same time in the geriatric hospital MRSA infection was prevalent. To decrease nosocomial infections some active preventive measures against hospital infection were taken since Oct. 1991. After introduction of preventive measures of hospital infection in the geriatric ward (190 beds) nosocomial bacteremia and pneumonia were markedly decreased in comparison of episode number before introduction of prevention. However several patients with MRSA colonization were observed every month. The aim of this clinical study was to clear how frequent MRSA was isolated from skin. Consequently 3 strains (3.4%) of MRSA were observed in 86 cultured skin. In conclusion we considered frequency of MRSA colonization frequency of MRSA colonization on skin was not so high but rather very low under the preventive measures.

A 71-year-old male visited our hospital because of diarrhea. At first we suspected infectious colitis and levofloxacin (300 mg/day) was administered for four days. But the diarrhea continued, so performed a barium enema after about 3 weeks from onset. Round polyposis from the rectum to the sigmoid colon were found. Colonoscopy was suggested to the patient, but was rejected. However diarrhea continued and fever appeared. Ceftriaxone (1 g/day) and sparfloxacin (200 mg/day) were administered, but the symptoms increased. He was admitted about 6 weeks from onset, and the colonoscopy showed multiple round yellow-white pseudomembranes. Pseudomembranous enterocolitis diagnosed because Clostridium difficile and its toxin were positive in the feces. After oral administration of vancomycin (1.5 g/day) was started, the symptoms alleviated rapidly and disappearance of pseudomembrane was confirmed by colonoscopy.

To study the role of Moraxella (subgenus Branhamella) catarrhalis (B. catarrhalis) adherence to airway cells in lower respiratory tract infections, the in vitro attachments of B. catarrhalis to upper airway (oropharyngeal) and lower airway (bronchial) epithelial cells were compared. The adherence of 4 strains (1 nonfimbriated and 3 fimbriated) of B. catarrhalis to respiratory tract epithelial cells collected from 11 patients with chronic pulmonary disease (CPD) and 11 healthy individuals was evaluated. Both the fimbriated and nonfimbriated strains showed increased attachment to oropharyngeal cells in the CPD patients (mean +/- SEM; 25.0 +/- 3.2/cell; P < 0.01) when compared to the control subjects (12.1 +/- 1.1/cell). On the average, the attachment to bronchial cells was 6.1 to 13.6 times greater per surface area (bacteria/micron2) than the attachment to oropharyngeal cells. The fimbriated strains tended to adhere in higher numbers to bronchial cells (19.0 +/- 1.8/cell) than the nonfimbriated strain (8.7 +/- 1.2/cell), although there was no difference between the CPD and control groups. In conclusion, the attachment of B. catarrhalis to oropharyngeal cells may be an enhancing factor for colonization in the upper respiratory tract in patients with CPD, and elevated adherence of the bacteria to bronchial cells may suggest pathogenic importance when mucociliary function is impaired.

We studied the clinical aspects of 18 patients from whom MRSA was detected from the stool and compared with 9 enterocolitis cases (7 male, 2 female, median age 72.4 y.o.) with 9 colonization cases (5 male, 4 female, median age 70.2 y.o.) from 1991 June to 1995 May. Cases of postoperative, use of anti-peptic ulcer drugs and administration of antibiotics for enterocolitis were more than that of colonization. On the other hand, eatable patients in the colonization group who could take food orally were more in number. Many patients of both enterocolitis and colonization were colonized in the respiratory tract. Drug sensitivity of MRSA in both cases were almost the same and the coagulase type were all that of II. Three courses on how MRSA enterocolitis occurs is considered. At first, colonization in the respiratory tract, second, proliferation of MRSA in the higher pH gastric juices as a result of gastrectomy or use of anti-peptic ulcer drugs, and third, selection of MRSA after administration of antibiotics.

In Plasmodium-infected mammals, phagocytosis and production of tumor necrosis factor (TNF) by monocytes and macrophages are prominent features. The present work aimed at clarifying the relationship between the maturation of human monocytes to macrophages and their TNF productivity and phagocytic ability in the presence of Plasmodium falciparum-infected erythrocytes. Fresh monocytes produced a significantly higher quantity of TNF in the presence of schizont-infected erythrocytes than macrophages obtained by in vitro monocyte maturation on autologous serum, whereas phagocytic activity of macrophages was much higher than that of fresh monocytes. This indicated that the TNF-inducing factors from P. falciparum-infected erythrocytes could stimulate fresh monocytes, but not macrophages, to release TNF, regardless of their development of phagocytosis. Activation of macrophages by interferon-gamma could not recover their TNF productivity in the presence of P. falciparum-infected erythrocytes, but it enhanced their TNF productivity in the presence of lipopolysaccharide(s). The TNF-inducing factors were contained mainly in erythrocytes infected with mature schizonts but not in erythrocytes infected with the younger stages of the parasites. Fractionation of infected erythrocytes revealed that both soluble and insoluble components almost equally contained those factors.

A hybrid cell line producing a monoclonal antibody (MAb) against Moraxella (Branhamella) catarrhalis lipopolysaccharide (LPS) was established. The specificity of the MAb 1B12 to purified rough LPSs from six strains of M. catarrhalis was ascertained by enzyme-linked immunosorbent assay (ELISA), competitive-inhibition ELISA, and immunoblotting. MAb 1B12 bound to live bacterial cells and culture supernatants from a total of 34 strains of M. catarrhalis, including 12 strains with different LPS serotypes. No cross-reactions with smooth and rough LPSs from selected enterobacterial and nonenterobacterial strains, with other respiratory pathogens, or with Neisseria species were observed. These data suggest that MAb 1B12 recognizes a common epitope of M. catarrhalis LPS which differs from serotype determinants.

Moraxella catarrhalis is one of the major pathogens of respiratory infections and has the ability to attach to the pharyngeal cells iva fimbriae. We characterized the epithelial cell receptor to which fimbriate M. catarrhalis binds. Neuraminidase pretreatment of pharyngeal epithelial cells resulted in a significant decrease of M. catarrhalis attachment, suggesting interaction with the sialic acid component. The attachment was not decreased in M. catarrhalis pretreated with 2 and 1 mg/ml of fucose, N-acetyl-neuraminic acid, N-acetyl-glucosamine, N-acetyl-galactosamine, acetyl-salicylic acid and colominic acid. However, M. catarrhalis treated with gangliosides M1, M2, D1a, D1b and T1a at a concentration of 2.5 micrograms/ml had significantly decreased the attachment compared to the control. In contrast treatment with gangliosides M3 and asialoganglioside M1 did not decrease the attachment of M. catarrhalis and thereby provided evidence for specificity of the inhibition. Concentration dependent effects of ganglioside M2 on the attachment were also observed. Other fimbriate isolates of M. catarrhalis showed decrease in attachment after treatment with ganglioside M2. However there was no effect on attachment when a nonfimbriate isolate was treated with ganglioside M2. This study indicates that the receptor of fimbriate M. catarrhalis on pharyngeal epithelial cells resides in the sequences of ganglioside M2.

The susceptibility of 101 pneumococcal isolates from the respiratory tract during 1991-1994 was examined and compared with the susceptibility of isolates over the period of 1975-1990. A rapid increase of resistance was seen not only to penicillin but also other antimicrobial agents. During 1991-1994, 38% of all the isolates were resistant to penicillin. The rates of resistance during this period were 16-23% for three newer cephalosporins, 18% for imipenem, 69% for tetracycline, 31% for erythromycin, 20% for chloramphenicol and 9% for clindamycin. The use of antibiotics within one month prior to pneumococcal isolation was correlated with penicillin resistance (P < 0.05). Serotyping of the isolates by antiserum revealed differences in predominant types between penicillin-resistant (19F, 23F,4) and -susceptible isolates (15, 4, 11A). Our data suggests that anti-pneumococcal antibiotics should be carefully chosen on the basis of susceptibility tests.

We investigated the interleukin-8 (IL-8) levels and neutrophil numbers in the sputum of 9 elderly patients with lower respiratory tract infections, including Pseudomonas aeruginosa infection, before and after treatment with various antimicrobial agents. The IL-8 levels in sputum supernatants and the neutrophil numbers in sputum smears from 9 patients decreased significantly after the elimination of the causative respiratory pathogens. We also demonstrated that human recombinant IL-8 at a range of 6.25-25 ng/ml significantly enhanced opsonophagocytic killing of P. aeruginosa immunotype-1 strain by human neutrophils in the presence of a serotype-specific anti-lipopolysaccharide monoclonal antibody and fresh normal human serum. These data suggest that the level of IL-8 production in the airways of patients with lower respiratory tract infections is dependent on bacterial densities, and indicate the important role of IL-8 not only in neutrophil migration but also in opsonophagocytic killing of bacteria in the lower respiratory tract.

We evaluated the sensitivity and specificity of polymerase chain reaction (PCR) for the detection of Mycobacterium tuberculosis among 109 patients who were suspected to have active pulmonary tuberculosis (PTB) and showed negative acid-fast bacilli (AFB) smears in a total of 393 samples of sputum (169), gastric aspirate (134), and urine (90) which fulfilled different criteria for the positivity of PCR. The patients were subsequently divided into one group of active PTB composed of 15 patients with definite PTB and 43 patients with highly suspected PTB, and another group of 51 non-active PTB patients. The PCR assay using samples of sputum and gastric aspirate proved to be specific for active PTB. The PCR method for diagnosis of active PTB using sputum samples was sensitive (97.8%) but lacked specificity (27.0%) when regarded as PCR positive when at least one positive reaction was obtained among all samples examined. However, the PCR of gastric aspirate demonstrated a sensitivity of 63.4% and a specificity of 76.7%. Our data supports that the PCR method for detecting active PTB in AFB smear negative patients using gastric aspirate shows markedly improved sensitivity over the conventional method (25.9%), although it still lacks specificity. PCR assay for M. tuberculosis using multiple samples of gastric aspirate in conjunction with careful clinical observations for the presence of active infection is essential for the diagnosis of active PTB among patients with negative AFB smear.

We studied clinical aspects of radiation pneumonitis from 1983 to 1992. Fifty seven patients admitted to our hospital because of lung cancer were treated with radiotherapy, and radiation pneumonitis developed in 20 (35.1%). The incidence of radiation pneumonitis was closely related to male sex, chronic obstructive lung disease, and chemotherapy. Pneumonitis was not related to age, or to the area or amount of radiation. Eighteen cases (90%) of pneumonitis occurred during or within one month after radiotherapy. In all but five cases (25%), pneumonitis was limited to the area of radiation. Treatment was mainly with steroids. In 4 cases (20%), pneumonitis recurred when steroid therapy was reduced, and five patients (10%) died.

We report a case of sarcoidosis complicated by middle lobe atelectasis. A chest radiograph and a chest CT film on admission revealed middle lobe atelectasis and mediastinal lymphadenopathy. Bronchofiberscopic findings showed slit-like stenosis and reddish, edematous mucosal change of the middle lobe orifice. On admission, the serum angiotensin-converting enzyme (ACE) level was within the normal range. However, the ACE level had increased beyond the normal range by 2 months later, histological examination of a specimen from a transbronchial lung biopsy (TBLB) of the middle lobe revealed noncaseating epithelioid cell granulomas. We diagnosed sarcoidosis because of the histological findings from the TBLB and serum ACE elevation. Treatment with predonisolone resulted in remarkable alleviation of middle lobe atelectasis and mediastinal lymphadenopathy. Cases of sarcoidosis with middle lobe atelectasis are rare in Japan.

In this clinical study we tried to find out the clinical significance of positive blood cultures between Jan. 1984 and Dec. 1989 in the Nagasaki Rosai Hospital. In this period the association between the isolated bacteria from blood cultures (398 specimens: 17.9%) and clinical background were evaluated. Each year the positive cultures were seen in about 18-20%. The distribution of bacteria showed increase percentage of the gram-positive organisms such as coagulase-negative Staphylococcus. Gram-negative organisms in included P. aeruginosa, A. calcoaceticus and E. coli. A. calcoaceticus was frequently found from the dept. of neurosurgery. Fungus, mostly Candida, was isolated in about 10-20%. The specimens were provided from department of internal medicine (62.9%) and neurosurgery (22.8%). An analysis of 213 episodes of 188 bacteremic cases was made. The onset of bacteremia had two peaks, 24 h or 1 month, after admission. The primary infected sites were the urinary tract (26.7%), respiratory system (14.5%) and central nervous system (6.1%). The central venous catheter was an important infected site. The major underlying diseases included acute cerebrovascular diseases, cardiac failure due to valvular heart diseases or acute myocardial infarction and/or iatrogenic immunocompromised state. The major complications were disseminated intravascular coagulation (DIC) (24.4%) and multiple organ failure (MOF) (8.9%). Half of the DIC episodes was caused by gram-positive cocci such as CNS, E. faecalis and MRSA. 68.4% of MOF episodes was associated with gram-negative bacteria. While the remainder was caused by gram-positive cocci including CNS and MRSA.(ABSTRACT TRUNCATED AT 250 WORDS)

The main pathogens of gram-negative infections are Neisseria gonorrhoeae, Neisseria meningitidis and Moraxella catarrhalis infection. N. Gonorrhoeae infection is one of the STD, but the chemotherapy for this infection is very easy because this pathogen is very susceptible to new quinolones. Meningococcal infection is very rare in Japan. Since 1980, M. catarrhalis is one of the important pathogen of respiratory infections such as acute bronchitis, pneumonia, chronic bronchitis. This pathogen also causes acute sinusitis and otitis. Most pathogenic strains of M. catarrhalis are beta-lactamase producing.

The factors involved in the mechanism of intractable bacterial infections are systemic, local and iatrogenic compromised conditions which mean the deficiency of host defence. From our results, especially on diffuse panbronchiolitis with Pseudomonas aeruginosa, we have learned about the harmful effects of destroyed neutrophils accumulated in bronchial and bronchiolar trees. Although low doses of erythromycin therapy is effective for intractable DPB. There are many evidences on the mechanisms for this treatment reported by Japanese researchers. We also reported our data of IL-8 level in BALF after this treatment. Bacterial factors of intractable processes are also important.

The mechanism of nosocomial respiratory infections caused by MRSA (methicillin-resistant Staphylococcus aureus) in geriatric patients was investigated. Seriously ill patients (SIP) undergoing naso-gastric tube feeding or intravenous hyperalimentation and moderately ill patients (MIP) who were orally fed, were examined for their colonization and infection by Staphylococcus aureus (S. aureus) in the respiratory tract. Colonization of MRSA in the upper respiratory tract in SIP was from six to ten times higher than that in MIP and was associated with a high incidence of MRSA pulmonary infections. In vitro S. aureus adherence to nasal or oropharyngeal cells demonstrated that bacteria binding to nasal cells was higher, which probably can be interpreted as an elevated occurrence of S. aureus colonization in the nasal cavity than in the throat. The binding activity of MRSA was not superior to that of MSSA (methicillin-sensitive S. aureus). Though MRSA binding to the nasal cells from SIP was not higher than those from MIP, MRSA colonization in the upper respiratory tract was more frequently seen in SIP (P < 0.01). A higher incidence of total infectious episodes (P < 0.02-0.001) and more frequent use of antibiotics (P < 0.02-0.001), which were potent against MSSA might be the basis for selection of MRSA in these patients. In fact, the rate of MRSA colonization on the skin (pressure sores) was also higher in SIP (P < 0.01). A low nutritional state in SIP (P < 0.01-0.02) might also be associated with MRSA colonization.(ABSTRACT TRUNCATED AT 250 WORDS)

Sputum during the acute exacerbation of chronic respiratory diseases were observed under the electron microscope, to determine the in vivo expression of surface structures of Branhamella catarrhalis (B. catarrhalis), the polymorphonuclear neutrophil (PMN) response to B. catarrhalis infections, and the composition of sputum. It was found that during infection fimbriae are expressed in B. catarrhalis. However, there were sparsely to densely fimbriated bacteria in each sputum sample. The length of the fimbriae were from 50 to 76 nm. In the sparsely fimbriated B. catarrhalis, external to the cell wall, a thin, granular, electron-dense layer was observed. Due to the presence of fimbriae, this layer was not seen in densely fimbriated B. catarrhalis. Blebs were also found in B. catarrhalis. PMNs were found to phagocytose both B. catarrhalis and debris. Evidence was found that debris were formed mainly by the destruction of PMNs. Bacteria as well as debris were phagocytosed by PMNs.

We report here a case of miliary tuberculosis with tubercular meningitis in which the polymerase chain reaction (PCR) amplification method was useful for its rapid diagnosis and follow up. A 70 year old male was hospitalized for further examination and treatment of diffuse small nodular shadows on the chest X-ray. After receiving antimicrobial therapy shadows still remained and he gradually lost visual acuity. He had no meningeal signs, and no remarkable finding on cranial CT. Cerebrospinal fluid examination showed increased cell number with predominantly lymphocytes. Cranial MRI (Gd DTPA) showed lateral ventricular ependymitis. Pulmonary tuberculosis and secondary tubercular meningitis were suspected, but we failed to detect microorganisms from the cerebrospinal fluid, gastric juice, sputum, and urine by the conventional method. However, by the polymerase chain reaction amplification method specific DNA fragments of Mycobacterium tuberculosis complex was detected from the cerebrospinal fluid, gastric juice, bronchoalveolar lavage fluid and serum. The final diagnosis of miliary tuberculosis with tubercular meningitis was established. We administered antitubercular drugs and observed the clinical course. He recovered and the polymerase chain reaction showed negative consequences in all samples. The judgement of PCR and the clinical course were compatible and parallel with the clinical course.