Genomic characterization of Staphylococcus aureus isolated from patients admitted to intensive care units of a tertiary care hospital: epidemiological risk of nasal carriage of virulent clone during admission

We conducted a molecular epidemiological study of Staphylococcus aureus using whole-genome sequence data and clinical data of isolates from nasal swabs of patients admitted to the intensive care unit (ICU) of Hiroshima University hospital. The relationship between isolate genotypes and virulence factors, particularly for isolates that caused infectious diseases during ICU admission was compared with those that did not. The nasal carriage rates of methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) in patients admitted to the ICU were 7.0% and 20.1%, respectively. The carriage rate of community-acquired (CA)-MRSA was 2.3%, accounting for 32.8% of all MRSA isolates. Whole-genome sequencing analysis of the MRSA isolates indicated that most, including CA-MRSA and healthcare-associated (HA)-MRSA, belonged to clonal complex (CC) 8 [sequence type (ST) 8] and SCCmec type IV. Furthermore, results for three disease foci (pneumonia, skin and soft tissue infection, and deep abscess) and the assessment of virulence factor genes associated with disease conditions [bacteremia, acute respiratory distress syndrome (ARDS), disseminated intravascular coagulopathy (DIC), and septic shock] suggested that nasal colonization of S. aureus clones could represent a risk for patients within the ICU. Particularly, MRSA/J and MSSA/J may be more likely to cause deep abscess infection; ST764 may cause ventilation-associated pneumonia, hospital-acquired pneumonia and subsequent bacteremia, and ARDS, and tst-1-positive isolates may cause DIC onset.IMPORTANCENasal colonization of MRSA in patients admitted to the intensive care unit (ICU) may predict the development of MRSA infections. However, no bacteriological data are available to perform risk assessments for Staphylococcus aureus infection onset. In this single-center 2-year genomic surveillance study, we analyzed all S. aureus isolates from nasal swabs of patients admitted to the ICU and those from the blood or lesions of in-patients who developed infectious diseases in the ICU. Furthermore, we identified the virulent clones responsible for causing infectious diseases in the ICU. Herein, we report several virulent clones present in the nares that are predictive of invasive infections. This information may facilitate the design of preemptive strategies to identify and eradicate virulent MRSA strains, reducing nosocomial infections within the ICU.

Comprehensive Genomic Characterization of Staphylococcus aureus Isolated from Atopic Dermatitis Patients in Japan: Correlations with Disease Severity, Eruption Type, and Anatomical Site

Atopic dermatitis (AD) shows frequent recurrence. Staphylococcus aureus is the primary microbial component in AD and is associated with disease activity. However, traditional typing methods have failed to characterize virulent AD isolates at the clone level. We conducted a comprehensive genomic characterization of S. aureus strains isolated from the skin of AD patients and healthy donors, comparing the whole-genome sequences of the 261 isolates with anatomical and lesional (AD-A)/nonlesional (AD-NL)/healthy sites, eruption types, clinical scores, virulence, and antimicrobial resistance gene repertoires in Japan. Sequence type (ST) diversity was lost with worsening disease activity; ST188 was the most frequently detected ST in AD-A and had the strongest correlation with AD according to the culture rate and proportion with worsening disease activity. ST188 and ST20 isolates inhabited all skin conditions, with significantly higher proportions in AD skin than in healthy skin. ST8, ST15, and ST5 proportions were equivalent for all skin conditions; ST30 was detected only in healthy skin; and ST12 was detected only in AD skin. ST97 detected in AD-A and healthy skin was clearly branched into two subclades, designated ST97A and ST97H. A comparison of two genomes led to the discovery that only ST97A possessed the complete trp operon, enabling bacterial survival without exogenous tryptophan (Trp) on AD skin, where the Trp level was significantly reduced. Primary STs showing an AD skin inhabitation trend (ST188, ST97A, ST20, and ST12) were all trp operon positive. The predominant clones (ST188 and ST97) possessed almost no enterotoxin genes, no mecA gene, and few other antimicrobial resistance genes, different from the trend observed in Europe/North America. IMPORTANCE While Staphylococcus aureus is a member of the normal human skin flora, its strong association with the onset of atopic dermatitis (AD) has been suggested. However, previous studies failed to assign specific clones relevant to disease activities. Enterotoxins produced by S. aureus have been suggested to aggravate and exacerbate the inflammation of AD skin, but their role remains ambiguous. We conducted a nuanced comprehensive characterization of isolates from AD patients and healthy donors, comparing the whole-genome sequences of the isolates with anatomical and lesional/nonlesional/healthy sites, eruption types, clinical scores, virulence, and antimicrobial resistance gene repertoires in Japan. We demonstrate that specific clones are associated with disease severity and clinical manifestations, and the dominant clones are devoid of enterotoxin genes and antimicrobial resistance genes. These findings undermine the established notion of the pathophysiological function of S. aureus associated with AD and introduce a new concept of S. aureus colonization in AD.

Primary bacterial intercostal pyomyositis diagnosis: A case report

RATIONALE

Pyomyositis is a microbial infection of the muscles and contributes to local abscess formation. Staphylococcus aureus frequently causes pyomyositis; however, transient bacteremia hinders positive blood cultures and needle aspiration does not yield pus, especially at the early disease stage. Therefore, identifying the pathogen is challenging, even if bacterial pyomyositis is suspected. Herein, we report a case of primary pyomyositis in an immunocompetent individual, with the identification of S aureus by repeated blood cultures.

PATIENT CONCERNS

A 21-year-old healthy man presented with fever and pain from the left chest to the shoulder during motion. Physical examination revealed tenderness in the left chest wall that was focused on the subclavicular area. Ultrasonography showed soft tissue thickening around the intercostal muscles, and magnetic resonance imaging with short-tau inversion recovery showed hyperintensity at the same site. Oral nonsteroidal anti-inflammatory drugs for suspected virus-induced epidemic myalgia did not improve the patient's symptoms. Repeated blood cultures on days 0 and 8 were sterile. In contrast, inflammation of the soft tissue around the intercostal muscle was extended on ultrasonography.

DIAGNOSES

The blood culture on day 15 was positive, revealing methicillin-susceptible S aureus JARB-OU2579 isolates, and the patient was treated with intravenous cefazolin.

INTERVENTIONS

Computed tomography-guided needle aspiration from the soft tissue around the intercostal muscle without abscess formation was performed on day 17, and the culture revealed the same clone of S aureus.

OUTCOMES

The patient was diagnosed with S aureus-induced primary intercostal pyomyositis and was successfully treated with intravenous cefazolin for 2 weeks followed by oral cephalexin for 6 weeks.

LESSONS

The pyomyositis-causing pathogen can be identified by repeated blood cultures even when pyomyositis is non-purulent but suspected based on physical examination, ultrasonography, and magnetic resonance imaging findings.

Heterogeneity of management practices surrounding operable gallbladder cancer - results of the OMEGA-S international HPB surgical survey

BACKGROUND

Gallbladder cancer (GBC) is an aggressive, uncommon malignancy, with variation in operative approaches adopted across centres and few large-scale studies to guide practice. We aimed to identify the extent of heterogeneity in GBC internationally to better inform the need for future multicentre studies.

METHODS

A 34-question online survey was disseminated to members of the European-African Hepatopancreatobiliary Association (EAHPBA), American Hepatopancreatobiliary Association (AHPBA) and Asia-Pacific Hepatopancreatobiliary Association (A-PHPBA) regarding practices around diagnostic workup, operative approach, utilization of neoadjuvant and adjuvant therapies and surveillance strategies.

RESULTS

Two hundred and three surgeons responded from 51 countries. High liver resection volume units (>50 resections/year) organised HPB multidisciplinary team discussion of GBCs more commonly than those with low volumes (p < 0.0001). Management practices exhibited areas of heterogeneity, particularly around operative extent. Contrary to consensus guidelines, anatomical liver resections were favoured over non-anatomical resections for T3 tumours and above, lymphadenectomy extent was lower than recommended, and a minority of respondents still routinely excised the common bile duct or port sites.

CONCLUSION

Our findings suggest some similarities in the management of GBC internationally, but also specific areas of practice which differed from published guidelines. Transcontinental collaborative studies on GBC are necessary to establish evidence-based practice to minimise variation and optimise outcomes.

Simultaneous Determination of Mycobacterium leprae Drug Resistance and Single-Nucleotide Polymorphism Genotype by Use of Nested Multiplex PCR with Amplicon Sequencing

Mycobacterium leprae is the predominant cause of leprosy worldwide, and its genotypes can be classified into four single-nucleotide polymorphism (SNP) types and 16 subtypes. Determining M. leprae drug resistance and genotype is typically done by PCR and Sanger DNA sequencing, which require substantial effort. Here, we describe a rapid method involving multiplex PCR in combination with nested amplification and next-generation sequence analysis that allows simultaneous determination of M. leprae drug resistance and SNP genotype directly from clinical specimens. We used this method to analyze clinical samples from two paucibacillary, nine multibacillary, and six type-undetermined leprosy patients. Regions in folP1, rpoB, gyrA, and gyrB that determine drug resistance and those for 84 SNP-InDels in the M. leprae genome were amplified from clinical samples and their sequences determined. The results showed that seven samples were subtype 1A, three were 1D, and seven were 3K. Three samples of the subtype 3K had folp1 mutation. The method may allow more rapid genetic analyses of M. leprae in clinical samples.

Roles of the three Mycobacterium smegmatis katG genes for peroxide detoxification and isoniazid susceptibility

Three different katG sequences (katGI, katGII and katGIII) were identified in the Mycobacterium smegmatis genome. The contributions of the three katG genes to survival of the bacterium were examined by constructing disruptants of these three genes. The katGIII sequence did not produce a functional catalase-peroxidase. Analyses of peroxidase activity and mRNA expression revealed that in wild type M. smegmatis, expression dominance between KatGI and KatGII was switched in the exponential and stationary growth phases. Susceptibility of the M. smegmatis gene disruptants to hydrogen peroxide (H₂ O₂ ) was tested in two growth phases. In the exponential phase, the katGI-null strain was more susceptible to H₂ O₂ than the katGII-null strain, indicating that KatGI plays a more important role in survival than KatGII in this growth phase. In contrast, in the stationary phase, growth of the katGII-null strain was inhibited at lower concentrations of H₂ O₂ . These results suggest that M. smegmatis has two types of catalase-peroxidases, expressions of which are controlled under different gene regulatory systems. Isoniazid (INH) susceptibilities of the katG-null strains were also examined and it was found that katGI is a major determinant of M. smegmatis susceptibility to INH.

Molecular characterization of Streptococcus pneumoniae, particularly serotype19A/ST320, which emerged in Krasnoyarsk, Russia

Streptococcus pneumoniae, a common human pathogen, colonizes the nasopharynx and causes diseases including acute otitis media (AOM). Herein, pneumococcal serotype distributions in children before and after PCV7 vaccination and in patients with pneumococcal disease in Siberian Russia (Krasnoyarsk) are reported. Analyses included antimicrobial susceptibility testing, sequence typing (ST), pulsed field gel electrophoresis, virulence‐related surface protein gene (VSG) typing with novel primers and structural analysis by scanning electron microscopy. In healthy children (HC) prior to administration of PCV7, drug‐susceptible serotype23F/ST1500 was a major pneumococcal genotype. In the PCV7 trial, multidrug‐resistant serotype19A/ST320 emerged in vaccinees after PCV7, exhibiting a PCV7‐induced serotype replacement. Multidrug‐resistant serotype19A/ST320 was evident in patients with AOM. Community‐acquired pneumonia (CAP) isolates showed genetic similarities to the AOM (ST320) genotype, constituting a common non‐invasive AOM–CAP group. In contrast, meningitis isolates were more divergent. Overall, 25 ST types were identified; five (20%) of which were Krasnoyarsk‐native. Regarding VSGs, PI‐1 (rlrA/rrgB), PI‐2 (pitA/B), psrP and cbpA were present at 54.3%, 38.6%, 48.6%, and 95.7%, respectively, with two major VSG content types, PI‐1⁻/PI‐2⁻/psrP⁺/cbpA⁺ and PI‐1⁺/PI‐2⁺/psrP^‐/cbpA⁺, being found for HC and non‐invasive diseases, respectively. A major clone of serotype19A/ST320 (PI‐1⁺/PI‐2⁺) produced the longest pneumococcal wire (pilus) structures in colonies. ST1016 (PI‐1⁻/PI‐2⁻) in HC had HEp‐2 cell‐adherent pili. These results suggest that serotype19A/ST320 and related genotypes, with the VSG content type PI‐1⁺/PI‐2⁺/psrP⁻/cbpA⁺, emerged in vaccinees after PCV7 in Siberia, accompanying diseases in non‐vaccinated children, and that some genotypes (serotypes19A/ST320 and 18/ST1016) produced novel pneumococcal structures, predicting their roles in colony formation and adherence.

The Study of Nursing NAVI

We have examined the nurses' thinking process in their professional judgment and action in the Partogram of 170 labors by 17 Midwifery students in 2 years.

Genomic comparison between Staphylococcus aureus GN strains clinically isolated from a familial infection case: IS1272 transposition through a novel inverted repeat-replacing mechanism

A bacterial insertion sequence (IS) is a mobile DNA sequence carrying only the transposase gene (tnp) that acts as a mutator to disrupt genes, alter gene expressions, and cause genomic rearrangements. "Canonical" ISs have historically been characterized by their terminal inverted repeats (IRs), which may form a stem-loop structure, and duplications of a short (non-IR) target sequence at both ends, called target site duplications (TSDs). The IS distributions and virulence potentials of Staphylococcus aureus genomes in familial infection cases are unclear. Here, we determined the complete circular genome sequences of familial strains from a Panton-Valentine leukocidin (PVL)-positive ST50/agr4 S. aureus (GN) infection of a 4-year old boy with skin abscesses. The genomes of the patient strain (GN1) and parent strain (GN3) were rich for "canonical" IS1272 with terminal IRs, both having 13 commonly-existing copies (ce-IS1272). Moreover, GN1 had a newly-inserted IS1272 (ni-IS1272) on the PVL-converting prophage, while GN3 had two copies of ni-IS1272 within the DNA helicase gene and near rot. The GN3 genome also had a small deletion. The targets of ni-IS1272 transposition were IR structures, in contrast with previous "canonical" ISs. There were no TSDs. Based on a database search, the targets for ce-IS1272 were IRs or "non-IRs". IS1272 included a larger structure with tandem duplications of the left (IRL) side sequence; tnp included minor cases of a long fusion form and truncated form. One ce-IS1272 was associated with the segments responsible for immune evasion and drug resistance. Regarding virulence, GN1 expressed cytolytic peptides (phenol-soluble modulin α and δ-hemolysin) and PVL more strongly than some other familial strains. These results suggest that IS1272 transposes through an IR-replacing mechanism, with an irreversible process unlike that of "canonical" transpositions, resulting in genomic variations, and that, among the familial strains, the patient strain has strong virulence potential based on community-associated virulence factors.

Emerging ST121/agr4 community-associated methicillin-resistant Staphylococcus aureus (MRSA) with strong adhesin and cytolytic activities: trigger for MRSA pneumonia and fatal aspiration pneumonia in an influenza-infected elderly

The pathogenesis of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) pneumonia in influenza-infected elderly individuals has not yet been elucidated in detail. In the present study, a 92-year-old man infected with influenza developed CA-MRSA pneumonia. His CA-MRSA was an emerging type, originated in ST121/agr4 S. aureus, with diversities of Panton–Valentine leucocidin (PVL)⁻/spat5110/SCCmecV⁺ versus PVL⁺/spat159^(etc.)/SCCmec⁻, but with common virulence potentials of strong adhesin and cytolytic activities. Resistance to erythromycin/clindamycin (inducible-type) and gentamicin was detected. Pneumonia improved with the administration of levofloxacin, but with the subsequent development of fatal aspiration pneumonia. Hence, characteristic CA-MRSA with strong adhesin and cytolytic activities triggered influenza-related sequential complications.

The emerging ST8 methicillin-resistant Staphylococcus aureus clone in the community in Japan: associated infections, genetic diversity, and comparative genomics

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a major concern worldwide. In the United States, ST8 CA-MRSA with SCCmecIVa (USA300) has been predominant, affecting the entire United States. In this study, we investigated Japanese ST8 CA-MRSA with new SCCmecIV1 (designated ST8 CA-MRSA/J), which has emerged in Japan since 2003. Regarding community spread and infections, ST8 CA-MRSA/J spread in 16.2-34.4% as a major genotype in the community in Japan, and was associated with skin and soft tissue infections (SSTIs), colitis, and invasive infections (sepsis, epidural abscesses, and necrotizing pneumonia), including influenza prodrome cases and athlete infections, similar to USA300. It spread to even public transport and Hong Kong through a Japanese family. Regarding genetic diversity, ST8 CA-MRSA/J included ST and spa variants and was classified into at least three pulsed-field gel electrophoresis types, ST8 Jα to γ. Of those, ST8 Jβ was associated with severe invasive infections. As for genomics, ST8 CA-MRSA/J showed high similarities to USA300, but with marked diversity in accessory genes; e.g., ST8 CA-MRSA/J possessed enhanced cytolytic peptide genes of CA-MRSA, but lacked the Panton-Valentine leukocidin phage and arginine catabolic mobile element, unlike USA300. The unique features of ST8 CA-MRSA/J included a novel mosaic SaPI (designated SaPIj50) carrying the toxic shock syndrome toxin-1 gene with high expression; the evolution included salvage (through recombination) of hospital-acquired MRSA virulence. The data suggest that ST8 CA-MRSA/J has become a successful native clone in Japan, in association with not only SSTIs but also severe invasive infections (posing a threat), requiring attention.

Unique features of the motility and structures in the flagellate polar region of Campylobacter jejuni and other species: an electron microscopic study

Similarly to Helicobacter pylori but unlike Vibrio cholerae O1/O139, Campylobacter jejuni is non-motile at 20°C but highly motile at ≥37°C. The bacterium C. jejuni has one of the highest swimming speeds reported (>100 μm/s), especially at 42°C. Straight and spiral bacterial shapes share the same motility. C. jejuni has a unique structure in the flagellate polar region, which is characterized by a cup-like structure (beneath the inner membrane), a funnel shape (opening onto the polar surface) and less dense space (cytoplasm). Other Campylobacter species (coli, fetus, and lari) have similar motility and flagellate polar structures, albeit with slight differences. This is especially true for Campylobacter fetus, which has a flagellum only at one pole and a cup-like structure composed of two membranes.

Recurrence of pelvic abscess from Panton-Valentine leukocidin-positive community-acquired ST30 methicillin-resistant Staphylococcus aureus

A 17-year-old female patient (a basketball player) suffered from recurrent pelvic abscesses from methicillin-resistant Staphylococcus aureus (MRSA). The first episode, from strain NN12, occurred in October 2004. Her cutaneous abscesses complicated into systemic progression to osteomyelitis and multifocal pelvic abscesses, adjacent to the sacroiliac joint. The second episode, abscesses at tissues adjacent to the sacroiliac joint from strain NN31A, occurred late in February 2005. The third episode, from strain NN31B, occurred on July 30, 2005, repeating the second episode. Three MRSA strains were identical in terms of genotypes (belonging to Panton-Valentine leukocidin [PVL]-positive ST30 community-acquired MRSA, CA-MRSA), pulsed-field gel electrophoresis patterns, and peptide cytolysin gene (psmα) expression levels. The three MRSA strains exhibited superior THP-1 cell invasion ability over hospital-acquired MRSA (New York/Japan clone). The data suggest that PVL-positive ST30 CA-MRSA, with high levels of cell invasion and peptide cytolysins, causes recurrence of pelvic abscesses in a healthy adolescent.

Elderly infection in the community due to ST5/SCCmecII methicillin-resistant Staphylococcus aureus (the New York/Japan clone) in Japan: Panton-Valentine leukocidin-negative necrotizing pneumonia

An 89-year-old man suffered from and died of necrotizing pneumonia with rapid progression and cavity formation due to methicillin-resistant Staphylococcus aureus (MRSA). He was at no risk for hospital-acquired MRSA infection. His MRSA exhibited genotype ST5/spa2(t002)/agr2/SCCmecII/coagulaseII and was negative for Panton-Valentine leukocidin, indicating the New York/Japan clone (the predominant epidemic hospital-acquired MRSA clone in Japan). However, this strain expressed the cytolytic peptide (phenol-soluble modulin or δ-hemolysin) genes at high level, similar to USA300 (the most common community-acquired MRSA in the United States), indicating a variant of the New York/Japan clone with an important feature of community-acquired MRSA.

Comparative genomics of community-acquired ST59 methicillin-resistant Staphylococcus aureus in Taiwan: novel mobile resistance structures with IS1216V

Methicillin-resistant Staphylococcus aureus (MRSA) with ST59/SCCmecV and Panton-Valentine leukocidin gene is a major community-acquired MRSA (CA-MRSA) lineage in Taiwan and has been multidrug-resistant since its initial isolation. In this study, we studied the acquisition mechanism of multidrug resistance in an ST59 CA-MRSA strain (PM1) by comparative genomics. PM1’s non-β-lactam resistance was encoded by two unique genetic traits. One was a 21,832-bp composite mobile element structure (MES_PM1), which was flanked by direct repeats of enterococcal IS1216V and was inserted into the chromosomal sasK gene; the target sequence (att) was 8 bp long and was duplicated at both ends of MES_PM1. MES_PM1 consisted of two regions: the 5′-end side 12.4-kb region carrying Tn551 (with ermB) and Tn5405-like (with aph[3′]-IIIa and aadE), similar to an Enterococcus faecalis plasmid, and the 3′-end side 6,587-bp region (MES_cat) that carries cat and is flanked by inverted repeats of IS1216V. MES_cat possessed att duplication at both ends and additional two copies of IS1216V inside. MES_PM1 represents the first enterococcal IS1216V-mediated composite transposon emerged in MRSA. IS1216V-mediated deletion likely occurred in IS1216V-rich MES_PM1, resulting in distinct resistance patterns in PM1-derivative strains. Another structure was a 6,025-bp tet-carrying element (MES_tet) on a 25,961-bp novel mosaic penicillinase plasmid (pPM1); MES_tet was flanked by direct repeats of IS431, but with no target sequence repeats. Moreover, the PM1 genome was deficient in a copy of the restriction and modification genes (hsdM and hsdS), which might have contributed to the acquisition of enterococcal multidrug resistance.

Electron microscopic structures, serum resistance, and plasmid restructuring of New Delhi metallo-β-lactamase-1 (NDM-1)-producing ST42 Klebsiella pneumoniae emerging in Japan

Enterobacteriaceae, carrying the New Delhi metallo-β-lactamase-1 (NDM-1) gene (bla (NDM-1)), have emerged and posed a threat since 2006. In Japan, bla (NDM-1)-carrying Escherichia coli was first described in 2010. In this study, we characterized NDM-1-positive Klebsiella pneumoniae strain 419 in Japan, which was isolated from the urine of a 90-year-old Japanese patient who had never been to the Indian subcontinent. K. pneumoniae 419 belonged to ST42. It possessed a surface capsule (with untypeable capsular PCR types) and was resistant to serum killing. K. pneumoniae 419 cells were occasionally flagellated or piliated and autoaggregated. K. pneumoniae 419 was resistant to β-lactams (including carbapenems), aminoglycosides, and fluoroquinolones, and was susceptible to imipenem (or biapenem), aztreonam, polymixin B, and colistin. It possessed at least eight plasmids; of those, a 74-kb plasmid (pKPJ1) of the replicon FIIA carried bla (NDM-1) and was conjugally transferred to E. coli strains, with a 71-kb transferable azithromycin-resistant (mphA (+)) plasmid of the replicon F (pKPJ2), as a large (145-kb) plasmid (pKPJF100) through a transposition event. In addition to bla (NDM-1), pKPJ1 carried arr-2, pKPJ2 carried mphA, and pKPJF100 carried both. They were negative for the 16S rRNA methylase gene, e.g., which is frequently associated with bla (NDM-1). The data demonstrate that K. pneumoniae 419 possessed virulence- and fitness-associated surface structures, was resistant to serum killing, and possessed a unique (or rare) genetic background in terms of ST type and bla (NDM-1)-carrying plasmid.

Accumulation of staphylococcal Panton-Valentine leukocidin in the detergent-resistant membrane microdomains on the target cells is essential for its cytotoxicity

The mechanisms for the cytotoxicity of staphylococcal Panton-Valentine leukocidin (PVL), a pore-forming toxin consisting of LukS-PV and LukF-PV, in human immune cells are still unclear. Because LukS-PV binds to ganglioside GM1, a constituent of detergent-resistant membrane microdomains (DRMs) of the plasma membrane, the role of DRMs in PVL cytotoxicity was examined in human polymorphonuclear neutrophils (PMNs), monocytes, HL-60 cells, and THP-1 cells. PVL binding capacities in HL-60 and THP-1 cells were higher than those in PMNs and monocytes; however, the PVL concentration to obtain more than 80% cell lysis in HL-60 cells was 10 times higher than that in PMNs and PVL even at such concentration induced < 10% cell lysis in THP-1 cells. After incubation of PMNs with LukS-PV, more than 90% of LukS-PV bound to the detergent-soluble membranes. Subsequent incubation with LukF-PV at 4 °C induced the accumulation of more than 70% of PVL components and 170- to 220-kDa complex formation in DRMs in an actin-independent manner. However, only 30% of PVL was found, and complex formation was under detectable level in DRMs in HL-60 cells. PVL did not accumulate in DRMs in THP-1 cells. Our observations strongly indicate that PVL accumulation in DRMs is essential for PVL cytotoxicity.

[Staphylococcus aureus (methicillin-resistant S. aureus: MRSA)]

Before antibiotic development, Staphylococcus aureus was a cause of serious invasive infections such as sepsis and meningitis and claimed many lives. However, even after antibiotic development, S. aureus posed a new threat as a major nosocomial pathogen, changing it to methicillin-resistant S. aureus (MRSA) since 1961. This year marks the 50th anniversary of the first report on MRSA. Today, there are two classes of MRSA spreading in hospitals and the community. The United States experienced invasive MRSA epidemics in 2005, and the latter MRSA (named CA-MRSA), especially USA300, affected the entire United States. As a countermeasure, guidelines for the management of MRSA infections were prepared in 2011. In Japan, there are people who are suffering from "hidden" epidemics in the community, falling behind in fighting CA-MRSA. We summarized current epidemic MRSA and infections.

Comparative genomics and drug resistance of a geographic variant of ST239 methicillin-resistant Staphylococcus aureus emerged in Russia

Two distinct classes of methicillin-resistant Staphylococcus aureus (MRSA) are spreading in hospitals (as hospital-acquired MRSA, HA-MRSA) and in the community (as community-acquired MRSA, CA-MRSA). Multilocus sequence type (ST) 239 MRSA, one of the most worldwide-disseminated lineages, has been noted as a representative HA-MRSA. Here, we isolated ST239 MRSA (spa type 3 [t037] and staphylococcal cassette chromosome mec [SCCmec] type III.1.1.1) and its novel variant with ST239/spa351 (t030)/SCCmecIII.1.1.4 (SCCmecIII_R) not only from hospitals but also from patients with urethritis in the community in Russia. The Russian variant (strain 16K) possessed a hybrid genome consisting of CC8 and CC30, similar to the ST239/spa3/SCCmecIII.1.1.1 HA-MRSA (TW20) genome, but with marked diversity. The 16K′ CC30 section had SCCmecIII_R carrying the dcs-carrying unit (which corresponded to the SCCmecIVc J3 joining region of ST30 CA-MRSA), lacked SCCmercury, and possessed a novel mobile element structure (MES16K) carrying the ccrC-carrying unit (with the recombinase gene ccrC1 allele 3) and drug resistance tranposons. The Russian variant included strains with a high ability to transfer its multiple drug resistance by conjugation; e.g., for strain 16K, the transfer frequency of a chloramphenicol resistance plasmid (p16K-1 with 2.9 kb in size) reached 1.4×10⁻², followed by Tn554 conjugative transfer at 3.6×l0⁻⁴. The Russian variant, which has been increasing recently, included divergent strains with different plasmid patterns and pulsed field gel electrophoresis profiles. The data demonstrate the alternative nature of ST239 MRSA as CA-MRSA and also as a drug resistance disseminator, and its micro but dynamic evolution in Russia.

Isotopic dependence of the giant monopole resonance in the even-A 112-124Sn isotopes and the asymmetry term in nuclear incompressibility

The strength distributions of the giant monopole resonance (GMR) have been measured in the even-A Sn isotopes (A=112-124) with inelastic scattering of 400-MeV alpha particles in the angular range 0 degrees -8.5 degrees . We find that the experimentally observed GMR energies of the Sn isotopes are lower than the values predicted by theoretical calculations that reproduce the GMR energies in 208Pb and 90Zr very well. From the GMR data, a value of Ktau = -550 +/- 100 MeV is obtained for the asymmetry term in the nuclear incompressibility.

Extensive multidrug resistance of coagulase-negative staphylococci in medical students

Staphylococcus aureus and coagulase-negative staphylococci (CNS) isolated from the nasal mucosa of medical students were examined for susceptibility to 16 antimicrobial agents. No methicillin-resistant S. aureus (MRSA) was isolated, while MRCNS was present in 23.5% of the medical students. CNS exhibited significantly more resistance to antimicrobial agents such as gentamicin, in addition to oxacillin, compared to S. aureus, and 13.1% of the CNS strains (mostly MRCNS) were multidrug-resistant (to five or more drugs). In contrast, ampicillin resistance was higher in S. aureus. The rate of hospitalization or of taking an antimicrobial agent within the past 1 year was lower in CNS+ students than in S. aureus+ students. The data suggest that CNS could serve as a reservoir of drug resistance by persistent colonization in the nasal mucosa. In this study, MRCNS with multidrug resistance was found in medical students. More attention should be given to nasal MRCNS in medical students as a possible spreader in hospitals.

A new technique for endoscopic submucosal dissection for early gastric cancer using an external grasping forceps

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) has improved the success rate of en-bloc resection. We report here on a new technique using an external grasping forceps.

PATIENTS AND METHODS

A total of 25 patients with suitable EGCs over 10 mm in diameter located in the gastric body were enrolled. After submucosal injection followed by circumcision of the lesion with a needle-knife, an external grasping forceps was introduced with the help of a second grasping forceps and anchored at the distal margin of the lesion. With gentle oral traction applied with this forceps, the lesion was dissected endoscopically in retroversion from the aboral side.

RESULTS

The mean lesion size was 15.0 mm (range 10 - 25 mm). Using the technique described, all lesions could be resected en bloc with free margins. The mean procedure time was 45 min (range 30 - 80 minutes). No significant bleeding requiring blood transfusion or perforation occurred.

CONCLUSIONS

This technical modification may simplify and shorten the gastric ESD procedure, except for lesions in distal locations, without compromising the efficacy.

Clinical significance of cytomegalovirus (CMV) antigenemia in the prediction and diagnosis of CMV gastrointestinal disease after allogeneic hematopoietic stem cell transplantation

To evaluate the clinical significance of a cytomegalovirus (CMV) antigenemia assay in the prediction and diagnosis of CMV gastrointestinal (CMV-GI) disease after hematopoietic stem cell transplantation (HSCT), 19 allogeneic HSCT recipients developing CMV-GI disease were retrospectively reviewed. All patients were monitored by a CMV antigenemia assay, at least once weekly after engraftment. The median onset of CMV-GI disease occurred 31 days post transplant (range: 19-62). Only four of 19 patients (21%) developed a positive CMV antigenemia test before developing CMV-GI diseases. Although all 19 patients subsequently developed positive CMV antigenemia tests during their clinical courses, the values remained at a low-level in nine (47%) patients. Among the 14 patients in whom results of real-time polymerase chain reaction (PCR) were available, seven (50%) yielded positive results of real-time PCR before developing CMV-GI disease. In contrast to the values of CMV antigenemia, all 14 patients exclusively yielded high viral loads (median: 2.8 x 10(4) copies/ml plasma). We conclude that CMV antigenemia testing has limited value in prediction or early diagnosis of CMV-GI disease, and that real-time PCR could have a more diagnostic significance.

Human intestinal epithelial cell-derived interleukin (IL)-18, along with IL-2, IL-7 and IL-15, is a potent synergistic factor for the proliferation of intraepithelial lymphocytes

Intestinal epithelial cell (IEC)-derived cytokines, such as stem cell factor (SCF), interleukin (IL)-7 and IL-15 are known to be required for the development of intestinal intraepithelial lymphocytes (IELs). A newly described cytokine, IL-18, has also been shown to be produced by intestinal epithelial cells. To demonstrate the functional effects of IL-18 on human IELs, we assessed IL-18/IL-18 receptor expression in IEC/IEL and proliferation following stimulation of intestinal IELs by IL-18. IL-18 transcripts were detected both in freshly isolated human colonic epithelial cells and in various colonic epithelial cell lines. IL-18 protein was also detected by ELISA and flow cytometric analysis using antihuman IL-18-specific monoclonal antibody (MoAb). Furthermore, IELs constitutively expressed the IL-18 receptor in addition to the IL-2 and IL-7 receptors. More importantly, IL-18 augmented significant proliferative responses of IEL in combination with IL-2, IL-7 and IL-15 both in the presence and in absence of anti-CD3 MoAb. These results suggest that IL-18 might play a crucial role in the proliferation and maintenance of intestinal IELs.

Contrasting action of IL-12 and IL-18 in the development of dextran sodium sulphate colitis in mice

BACKGROUND

Interleukin (IL)-12 and IL-18 are major interferon (IFN)-gamma-inducing factors that collaborate with each other. The present study was conducted to determine the distinct roles of IL-12 and IL-18 in the development of dextran sulphate sodium (DSS) colitis in mice.

METHODS

Colitis was induced in IL-12p35(-/-), IL-18(-/-), IL-18 receptor(-/-) and control mice with DSS. Clinical and histopathological analysis was conducted using survival rate, weight loss score, diarrhoea score, bloody stool score and histological score. In addition, cytokine production by lamina propria mononuclear cells (LPMCs) was examined using the specific enzyme-linked immunoassay.

RESULTS

IL-12p35(-/-) mice developed only a mild disease associated with no lethality and few histopathological abnormalities. In contrast, IL-18(-/-) and IL-18R(-/-) mice developed more severe colitis associated with high lethality and more histopathological abnormalities compared with control mice. LPMCs from DSS-fed IL-18(-/-) mice produced significantly higher amounts of IFN-gamma, while LPMCs from DSS-fed IL-12(-/-) mice produced lower amounts of IFN-gamma and tumour necrosis factor (TNF)-alpha compared with control mice.

CONCLUSION

These results suggest that IL-18 might function with manners different from IL-12 at some pathological conditions in the development of colitis.

Anesthesia-related mortality and morbidity over a 5-year period in 2,363,038 patients in Japan

BACKGROUND

Statistical data of mortality and morbidity related to anesthesia have not been reported in Japan since World War II. The need to comprehensively examine the events of cardiac arrest as well as mortality prompted the first national study in Japan.

METHODS

Confidential questionnaires were sent to all Japan Society of Anesthesiologists Certified Training Hospitals every year from 1994 through 1998. Collected data were analyzed for incidence of cardiac arrest and other critical events during anesthesia and surgery, and their outcomes within 7 postoperative days. The principal causes of the critical incidents were also analyzed.

RESULTS

With an average response rate of 39.9%, a total of 2,363,038 cases were documented over 5 years. The average incidence per year of cardiac arrest during surgery due to all etiologies and that totally attributable to anesthesia was 7.12 [95%CI: 6.30,7.94] and 1.00 [0.88, 1.12]) per 10,000 cases, respectively. The average mortality per year in the operating room or within 7 postoperative days due to all etiologies and that totally attributable to anesthesia was 7.18 [6.22, 8.13] and 0.21 [0.15, 0.27] per 10,000 cases, respectively. The two principal causes of cardiac arrest during anesthesia and surgery due to all etiologies were massive hemorrhage (31.9%) and surgery (30.2%), and those totally attributable to anesthesia were drug overdose or selection error (15.3%) and serious arrhythmia (13.9%). Preventable human errors caused 53.2% of cardiac arrest and 22.2% of deaths in the operating room totally attributable to anesthesia.

CONCLUSIONS

The rates in Japan of cardiac arrest and death during anesthesia and surgery due to all etiologies as well as those totally attributable to anesthesia are comparable to those of other developed countries.

Validity of simple mucosal biopsy criteria combined with endoscopy predicting patients with ulcerative colitis ultimately requiring surgery: a multicenter study

BACKGROUND

Recent mucosal biopsy criteria combined with endoscopy effectively differentiate patients with ulcerative colitis ultimately requiring surgery (UC-S) from those receiving medication alone (UC-M). However, the criteria were inconvenient in practical use because of the need for complicated calculations, and the validity has not been verified in other institutes where the indications for surgery may differ. The aims of this multicenter study were to propose simple criteria in which calculation can be performed by mental arithmetic and to measure their validity.

METHODS

Based on the above original criteria, we constructed simple criteria in which coefficients and constant were simplified to integral numbers. The criteria consisted of the diagnostic categories, highest-risk, high-risk, unpredictable, low-risk, and lowest-risk of surgery. The validity of these proposed criteria was evaluated in 121 patients with UC-S and 186 with UC-M from 11 institutes.

RESULTS

The categories of high-risk and low-risk had sensitivities exceeding 86.0% and specificities exceeding 95.2%, and the validities were maintained at high levels in most individual institutes. There was little difference in validity between the proposed and original criteria when testing using the same patients.

CONCLUSIONS

Despite simplified coefficients and constant, the proposed criteria reliably predicted the eventual clinical outcome of patients with ulcerative colitis and would be helpful in determining the necessity of surgery.

Dose-adjusted preemptive therapy for cytomegalovirus disease based on real-time polymerase chain reaction after allogeneic hematopoietic stem cell transplantation

We have prospectively evaluated the efficacy of real-time PCR-guided preemptive therapy for CMV diseases in allogeneic hematopoietic stem cell transplant recipients with grades II-IV acute GVHD. The dose of ganciclovir was adjusted according to the viral load determined by real-time polymerase chain reaction (PCR). On detecting CMV reactivation in the plasma, ganciclovir was initiated at a dose of 5 mg/kg body weight once daily, and the dose was increased to twice daily if viral load continued to increase after initiating ganciclovir. In 39 evaluable patients, CMV reactivation assessed by real-time PCR became positive in 30 (77%). One developed CMV gastroenteritis before PCR became positive. Thus the remaining 29 patients were treated preemptively with ganciclovir. The dose of ganciclovir was increased in 12 patients (41%) of preemptively treated patients for increasing viral load. CMV diseases were diagnosed in two patients (one gastroenteritis and one retinitis), and late CMV disease was diagnosed in one patient (gastritis). The treatment was generally well-tolerated, but three patients (10%) developed neutropenia (neutrophil count less than 1.0 x 10(9)/l). In conclusion, real-time PCR-guided preemptive therapy with decreased dose of ganciclovir is feasible and does not increase the frequency of CMV diseases if the dose is adjusted according to the viral load.

A case of systemic lupus erythematosus presenting with rectal ulcers as the initial clinical manifestation of disease

Gastrointestinal involvement is often seen in patients with systemic lupus erythematosus (SLE). All parts of the gastrointestinal tract may be affected. However, rectal involvement at onset is rare. We describe here a case of SLE in which rectal ulcers due to vasculitis occurred as the initial manifestation of the disease without involvement of any other organ. The ulcers worsened, along with the appearance of lupus nephritis 5 years later When steroid therapy was initiated, there was rapid clinical and radiographic improvement. Our case suggests that rectal ulcer is a rare but important complication of SLE and can represent the initial and sole clinical manifestation of the disease.

[Annual study of perioperative mortality and morbidity for the year of 1999 in Japan: the outlines--report of the Japan Society of Anesthesiologists Committee on Operating Room Safety]

Anesthetic mortality and morbidity in Japan Society of Anesthesiologists (JSA) Certified Training Hospitals (CTH) for the year 1999 were reported as continuation of annual studies started in 1993. The JSA Committee on Operating Room Safety (CORS) sent confidential questionnaires to 774 CTH and received valid responses from 60.3% of hospitals. A total number of 793,840 anesthetics were documented. The respondents were asked to report all cases of cardiac arrests and other critical incidents (serious hypotension, serious hypoxemia and others), and their outcomes (death in operating room, death within 7 days, transfer to vegetative state and rescue without sequelae) as well as one principal cause for each incident from list of 52 items. They were also requested to submit the tabulation of patients by ASA physical status, age distribution, surgery sites and anesthetic methods. Analysis was made by total incidents under anesthesia/surgery, and also by incidents totally attributable to anesthetic management (AM), due to preoperative complications (PC), due to intraoperative pathological events (IP) and due to surgery (SG), with special reference to each of four tabulation groups and the whole group of patients. This paper focused analysis on all patients, as analyses with special reference to ASA physical status, age distribution, surgery sites and anesthetic methods were previously reported. Total incidence of cardiac arrest under anesthesia/surgery was 6.53 per 10,000 anesthetics. PC, IP and SG represented principal causes in 42.9%, 22.0% and 21.4% causes of total cardiac arrest cases, respectively. AM was noted as the principal cause in 12.0% of cases, with an incidence rate of 0.78 per 10,000. In 52 more detailed classification of principal causes, the most frequent cause of cardiac arrest was preoperative hemorrhagic shock, 20.3% of all cardiac arrests. The second cause was massive hemorrhage and/or hypovolemia due to surgical procedures (13.1%), and the third was intraoperative myocardial infarction/coronary ischemia/coronary spasm (9.5%). Prognoses of cardiac arrest cases declined due to PC: 71.1% of cardiac arrests died in the operating room or within 7 days after surgery and only 19.8% survived without sequelae. The best prognoses were found in cardiac arrest cases due to AM: 69.4% survived without sequelae and 12.9% died. The mortality rate post-cardiac arrest was 3.44 per 10,000 anesthetics, of those 0.10 due to AM, 0.57 due to IP, 1.99 due to PC and 0.76 due to SG. The mortality rate after critical incidents other than cardiac arrest such as severe hypotension and severe hypoxemia was 3.75, of those 0.03 due to AM, 0.28 due to IP, 2.31 due to PC and 1.13 due to SG. The final mortality rate attributable to anesthesia/surgery including deaths post-cardiac arrest and after other critical incidents was 7.19 per 10,000 anesthetics and very close to 7.18 [6.22, 8.13], that of mean [95% C.I.] in 1994-1998. The final mortality rate totally attributable to anesthesia was 0.13 per 10,000 anesthetics, which was significantly improved from 0.21 [0.15, 0.27], that of mean [95% C.I.] in 1994-1998. IP, PC and SG showed the final mortality rate of 0.84, 4.30 and 1.89, respectively. Five major causes of all critical incidents were massive hemorrhage due to surgical procedures (20.8%), preoperative hemorrhagic shock (10.7%), surgical technique (8.0%), inappropriate airway management (5.2%) and intraoperative myocardial infarction and coronary ischemia (4.5%). Drug overdose or selection error (3.9%) and overdose of main anesthetic (2.9%) as a result of human error occupied the 7th and 10th places. As far as anesthetic management to reduce mortality and morbidity related to anesthesia is concerned, we should increase vigilance to avoid human errors in addition to improving preanesthetic preparations and assessment of cardiovascular status as well as intraoperative management of cardiovascular events.

[Perioperative mortality and morbidity for the year 1999 in 466 Japanese certified anesthesia-training hospitals: with special reference to operative regions--report of Committee on Operating Room Safety of Japanese Society of Anesthesiologists]

Perioperative mortality and morbidity in Japan for the year 1999 were analyzed retrospectively with special reference to operative regions. The total number of analyzed cases was 701,940. The percentages for each operative region were as follows, craniotomy 4.5%, thoracotomy 3.3%, heart and great-vessels 3.9%, thoracotomy with laparotomy 0.8%, laparotomy except caeserian-section 31.7%, ceserian-section 3.2%, head-neck and otolarynx 14.5%, chest-abdomen-perineum 11.1%, spine 3.5%, extremity including peripheral-vessel 16.5%, and others 6.9%. The incidence of serious events, including cardiac arrest and severe hypotension and hypoxemia suggesting impending cardiac arrest was 34.58 per 10,000 cases in all operative regions. The events were observed more frequently in heart and great-vessels 247.26, thoracotomy with laparotomy 128.91 and thoracotomy 61.55, and less frequently in chest-abdomen-perineum 13.52 and extremity including peripheral-vessel 16.99. Regarding the prognosis of events, the cases with no sequela were 69.9% in all operative regions. While there were fewer cases with no sequela in craniotomy 50.4%, thoracotomy with laparotomy 54.3% and heart and great-vessels 58.6%, there were more cases in head-neck and oto-larynx 95.2% and chest-abdomen-perineum 90.5%. The incidence of serious events totally attributable to anesthetic management was 7.79 per 10,000 cases in all operative regions. The events were observed more frequently in thoracotomy 12.82, heart and great-vessels 12.29 and spine 11.06, and less frequently in extremity including peripheral-vessel 5.17 and chest-abdomen-perineum 6.05. Regarding the prognosis of events, the cases with no sequela were 93.1% in all operative regions. There were fewer cases with no sequela in thoracotomy with laparotomy 80.0% and craniotomy 81.8%. The main cause of events in thoracotomy and spine was the inadequate airway management, and in heart and great-vessels was the overdose or miss-selection of drugs. Although the incidence of serious events totally attributable to anesthetic management was one fourth of all events, most of them resulted from human factors. Thus, the more efforts are necessary to improve the outcomes. While the total deaths from 701,940 cases, including death on the operation day or within 7 days after it, were 528 cases (7.52 per 10,000 cases), the deaths totally attributable to anesthesia were 7 cases (0.10 per 10,000 cases).

[Annual report of perioperative mortality and morbidity for the year 1999 with a special reference to anesthetic methods at Certificated Training Hospitals of Japanese Society of Anesthesiologists]

The Committee on Operating Room Safety of Japanese Society of Anesthesiologists (JSA) sends annually confidential questionnaires of perioperative mortality and morbidity to Certificated Training Hospitals of JSA. This report is on perioperative mortality and morbidity in 1999 with a special reference to anesthetic methods. Four hundred and sixty-seven hospitals reported the number of cases referred to anesthetic methods and total numbers of cases were 727,723. The incidences of cardiac arrest per 10,000 cases due to all etiology are estimated to be 6.77 cases in average, 5.33 cases in inhalation anesthesia, 34.26 cases in total intravenous anesthesia (TIVA), 5.26 cases in inhalation anesthesia plus epidural or spinal or conduction block, 5.29 cases in TIVA plus epidural or spinal or conduction block, 0.73 cases in spinal with continuous epidural block (CSEA), 2.85 cases in epidural anesthesia, 1.63 cases in spinal anesthesia, 2.53 cases in conduction block and 46.51 cases in other methods. However, the incidences of cardiac arrest per 10,000 cases totally attributable to anesthesia are estimated to be 0.78 case in average, 0.51 case in inhalation anesthesia, 1.35 cases in TIVA, 0.97 case in inhalation anesthesia plus epidural or spinal or conduction block, 1.51 cases in TIVA plus epidural or spinal or conduction block, 0.73 case in CSEA, 1.71 cases in epidural anesthesia, 0.54 case in spinal anesthesia, 2.52 cases in conduction block and 1.08 cases in other methods. The incidences of severe hypotension per 10,000 cases due to all etiology are estimated to be 16.64 cases in average, 13.61 cases in inhalation anesthesia, 100.36 cases in TIVA, 13.32 cases in inhalation anesthesia plus epidural or spinal or conduction block, 9.07 cases in TIVA plus epidural or spinal or conduction block, 3.65 cases in CSEA, 6.26 cases in epidural anesthesia, 7.31 cases in spinal anesthesia, 2.52 cases in conduction block and 28.12 cases in other methods. On the other hand, the incidences of cardiac arrest per 10,000 cases totally attributable to anesthesia are estimated to be 2.40 cases in average, 1.65 cases in inhalation anesthesia, 0.81 cases in TIVA, 3.92 cases in inhalation anesthesia plus epidural or spinal or conduction block, 2.77 cases in TIVA plus epidural or spinal or conduction block, 2.56 cases in CSEA, 3.42 cases in epidural anesthesia, 2.71 cases in spinal anesthesia, zero case in conduction block and zero case in other methods. The incidences of severe hypoxia per 10,000 cases due to all etiology are estimated to be 5.32 cases in average, 6.7 cases in inhalation anesthesia, 9.17 cases in TIVA, 5.16 cases in inhalation anesthesia plus epidural or spinal or conduction block, 4.53 cases in TIVA plus epidural or spinal or conduction block, 2.56 cases in CSEA, zero case in epidural anesthesia, 1.08 cases in spinal anesthesia, zero case in conduction block and 1.08 cases in other methods. On the other hand, the incidences of severe hypoxia per 10,000 cases totally attributable to anesthesia are estimated to be 2.39 cases in average, 3.22 cases in inhalation anesthesia, 2.43 cases in TIVA, 2.26 cases in inhalation anesthesia plus epidural or spinal or conduction block, 2.77 cases in TIVA plus epidural or spinal or conduction block, zero case in CSEA, zero case in epidural anesthesia, 0.54 cases in spinal anesthesia, zero case in conduction block and 1.08 cases in other methods. The mortality rates of cardiac arrest per 10,000 cases due to all etiology are estimated to be 3.56 cases in average, 2.82 cases in inhalation anesthesia, 24.55 cases in TIVA, 1.4 cases in inhalation anesthesia plus epidural or spinal or conduction block, 1.51 cases in TIVA plus epidural or spinal or conduction block, zero cases in CSEA, 0.57 cases in epidural anesthesia, 0.27 cases in spinal anesthesia, zero case in conduction block and 42.18 cases in other methods. On the other hand, the mortality rates of cardiac arrest per 10,000 cases totally attributable to anesthesia are estimated to be 0.08 case in average, 0.09 case in inhalation anesthesia, 0.27 case in TIVA, 0.05 case in inhalation anesthesia plus epidural or spinal or conduction block, zero case in TIVA plus epidural or spinal or conduction block, zero case in CSEA, 0.57 case in epidural anesthesia, zero case in spinal anesthesia, conduction block and other methods. The outcomes of cardiac arrest totally attributable to anesthesia are 70.2% of full recovery without any sequelae, 10.5% of death within 7 days, 1.8% of vegetative state and 17.5% of unknown results while the outcome of critical events including severe hypotension and severe hypoxia totally attributable to anesthesia is 94.9% of full recovery without any sequelae, 0.4% of death within 7 days, 0.2% of vegetative state and 4.5% of unknown results. These results indicate that there are no differences in mortality and morbidity totally attributable to anesthesia among anesthetic methods in 1999 at Certificated Training Hospitals of Japan Society of Anesthesiologists.

Measurement of colonic mucosal concentrations of 5-aminosalicylic acid is useful for estimating its therapeutic efficacy in distal ulcerative colitis: comparison of orally administered mesalamine and sulfasalazine

OBJECTIVES

Oral 5-aminosalicylic acid (5-ASA) preparations have been used frequently in the treatment of ulcerative colitis. However, there have been few reports investigating the relationship between colonic mucosal concentrations of 5-ASA and its clinical efficacy when oral sulfasalazine or 5-ASA compounds were administered. The aim of this study is to compare the mucosal concentrations of 5-ASA ensured by sulfasalazine or mesalamine, and to define the clinical significance of the measurement of 5-ASA concentrations in the treatment of distal ulcerative colitis.

MATERIALS AND METHODS

Biopsies were taken from the rectum and sigmoid colon of the oral sulfasalazine group (n = 13) and the slow-release 5-ASA (mesalamine) group with (n = 5) or without (n = 11) rectal administration of 5-ASA. High-pressure liquid chromatography was used to measure the tissue concentrations of 5-ASA and its metabolites. We compared the 5-ASA concentrations of the sulfasalazine group with the mesalamine group. Furthermore, we analyzed the relationship between tissue 5-ASA concentrations and the Disease Activity Index (DAI).

RESULTS

The concentrations of 5-ASA and acetyl-5-ASA in the sulfasalazine group were higher than those in the group taking oral mesalamine alone (p < 0.01). The concentration of 5-ASA was much higher in the patients who received oral and rectal mesalamine in an enema than in the patients who had oral mesalamine alone. There was a significant inverse correlation between the DAI and concentrations of 5-ASA in the rectum (r = 0.712, p < 0.001).

CONCLUSIONS

We demonstrated that the colonic mucosal concentration of 5-ASA was significantly higher in the sulfasalazine group than in the mesalamine group. Furthermore, the concentrations of mucosal 5-ASA may be a good marker for the estimation of its efficacy in the treatment of ulcerative colitis.

[Perioperative mortality and morbidity in 1999 with a special reference to age in 466 certified training hospitals of Japanese Society of Anesthesiologists--report of Committee on Operating Room Safety of Japanese Society of Anesthesiologists]

Perioperative mortality and morbidity in Japan from Jan. 1 to Dec. 31, were studied retrospectively. Committee on Operating Room Safety of Japanese Society of Anesthesiologists (JSA) sent confidential questionnaires to 774 Certified Training Hospitals of JSA and received answers from 60.2% of the hospitals. We analyzed their answers with a special reference to the age group. The total number of anesthetics available for this analysis was 732,788. All cases were divided in to 7 groups; group A(< 1 months), group B(< 12 months), group C(< 5 years), group D(< 18 years), group E (< 65 years), group F(< 85 years), and group G(> 85 years). The incidences of all critical events including cardiac arrest, severe hypotension, and severe hypoxemia were 168.14, 47.86, 24.63, 14.65, 28.43, 50.4, and 43.68 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The overall mortality rate (death during anesthesia and within 7th postoperative day) were 74.10, 6.63, 3.30, 3.07, 4.82, 13.74, and 11.84 per 10,000 anesthetics in patients with group A, B, C, D, E, F, and G, respectively. The incidences of cardiac arrest were 54.15, 8.84, 5.08, 2.56, 4.84, 11.02, and 6.66 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The mortality rates after cardiac arrest were 42.75, 2.95, 2.54, 1.70, 2.00, 6.56, and 5.18 in patients with group A, B, C, D, E, F, and G, respectively. The incidences of all critical events, the incidence of cardiac arrest, and the overall mortality rate were much higher in group A than other groups and lower in group D. Mortality and morbidity due to all kinds of causes including anesthetic management, intraoperative events, co-existing diseases, and operation were as follows. The incidence of all critical events attributable to co-existing disease were the highest in these four groups, and 94.04, 15.46, 7.87, 6.13, 7.26, 17.38, and 16.29 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The incidences of all critical events attributable to anesthetic management were 31.35, 16.94, 4.60, 6.09, 10.77, and 14.07 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The incidence of cardiac arrest in group A was much more attributable to co-existing disease and operation than other causes. The incidences of cardiac arrest attributable to anesthetic management were 0.00, 1.47, 0.25, 0.34, 0.83, 0.92, and 0.22 per 10,000 in patients with group A, B, C, D, E, F, and G, respectively. The mortality rates in these groups were 0.00, 0.00, 0.00, 0.17, 0.07, 0.05, and 1.48, and no death was found in cases under 5 years of age. The two cases of death in G group were due to too high anesthesia levels in spinal anesthesia. Other causes including overdose of anesthetics, toxic effect of local anesthetic, improper management of airway, and incompatible blood transfusion were preventable with the anesthesiologists' effort in protocol development and skilled assistance.

Restricted V(H) gene usage in lamina propria B cells producing anticolon antibody from patients with ulcerative colitis

BACKGROUND AND AIMS

Autoimmune responses against colonic epithelium may play a role in the development of colonic inflammation associated with ulcerative colitis (UC). In this study, we established and characterized B-cell lines and clones that produced anticolon antibody from inflamed colonic mucosa of UC subjects.

METHODS

B-cell lines were generated through Epstein-Barr virus transformation of lamina propria lymphocytes (LPLs) from colonic mucosa and peripheral blood lymphocytes, and these lines were screened for the production of anticolon antibodies. B-cell lines were then cloned by limiting dilution culture, and messenger RNA expression of immunoglobulin heavy-chain variable region (V(H)) was assessed.

RESULTS

V(H) gene families used in B-cell lines established from LPLs of normal controls were diverse, and B-cell lines from UC LPLs expressed a restricted V(H)3 family usage. All 15 clones from UC used a restricted V(H)3 gene family, whereas diverse V(H) gene families were used by 24 clones from normal controls. The analysis of nucleotide sequences indicated that these clones were derived from various germline gene segments.

CONCLUSIONS

The restricted V(H) gene usage in anticolon autoantibodies producing B-cell clones suggests that a particular antigenic stimulus contributes to the pathogenesis of UC.

Conformational stability and warfarin-binding properties of human serum albumin studied by recombinant mutants

Correctly folded recombinant wild-type human serum albumin and the single-residue mutants K199A, W214A, R218H and H242Q were produced with the use of a yeast expression system. The changes in R218H resulted in a pronounced decrease in intrinsic fluorescence. Thermodynamic parameters for thermal denaturation of the present mutants and of five additional mutants have been determined, showing small increases in stability for two mutants (R218H and H242Q) and a larger decrease in stability for one (W214A). In the last of these, denaturation was a heterogeneous process starting at physiological temperature. The high-affinity binding constant for warfarin at pH 7.4 was determined by fluorescence spectroscopy: there was a significant increase in affinity for binding of warfarin to H242Q and K199A and a smaller decrease in affinity for W214A and R218H. The findings show that Trp-214 is not as essential for the high-affinity binding of warfarin as has previously been thought.