Antifungal activity of the bioactive substance from Bacillus atrophaeus strain HAB-5 and its toxicity assessment on Danio rerio.

The prevalence of pathogen inhibitors bacteria has motivate the study for antimicrobial compounds. Bioactive fungicide have always received considerable attention. A bacterial isolated strain HAB-5 showed antifungal activity against plant fungi. Based on morphological, physiological, biochemical and 16SrDNA sequence analysis, the strain was identified to be a Bacillus atrophaeus. This strain possessed a broad spectrum antifungal activity against various plant pathogenic fungi. Extraction of antifungal substance was performed and the crude extract had potent antifungal ability and showed great potential for swelling and inhibiting spore germination. This antifungal displayed heat stability and active in a wide pH range 5.0-10.0. Moreover no reduction was found in its activity after enzyme treatment. The toxicity test was evaluated in Danio rerio. The acute toxicity test indicated that the 24, 48, 72, 96h LC50 values of UMTLS to the zebrafish were 14.4, 13.8, 13.4, and 12.9%, respectively. Based on the results obtained in this study, antifungal substance was not toxic to zebra. Analyses of disease suppression showed that HAB-5 was effective to reduce the incidence of anthracnose symptoms on mango fruits, also prevent disease infection and protect tobacco seedling from Phytophtora nicotianae. The bioactive substance from Bacillus atrophaeus HAB-5 could be a candidate in the generation of new antifungal agents in crop.

The role of Toll-like receptors in periodontitis.

Periodontitis is a common infectious disease. Recent studies have indicated that the progression of periodontitis may be regulated by interactions between host immunity and periodontopathic bacteria. Although periodontopathic bacteria can destroy periodontal tissue, a dysfunctional host immune response triggered by the bacteria can lead to more severe and persistent destruction. Toll-like receptors (TLRs), a type of pattern recognition receptor (PRR) that recognizes pathogens, have been implicated in host innate immune responses to periodontopathic bacteria and in the activation of adaptive immunity. TLR-targeted drugs may hold promise to treat periodontal disease. This review summarizes recent studies on the role of TLRs in periodontitis and discusses areas needing further research. We believe TLRs may be an effective biomarker for the prevention, diagnosis, and treatment of periodontitis in the near future.

Higher rate of colorectal cancer among patients with pyogenic liver abscess with Klebsiella pneumoniae than those without: an 11-year follow-up study.

AIM: Pyogenic liver abscess (PLA) has been reported as an early manifestation of colorectal cancer (CRC) in adults, but few studies have investigated this relationship. It is unclear if patients with Klebsiella pneumoniae PLA are at increased risk of subsequent CRC. Our aims were to estimate the incidence of CRC among patients with PLA and to compare the incidence of CRC between K. pneumoniae PLA and non-K. pneumoniae PLA groups. METHOD: We conducted a retrospective study of patients with PLA diagnosed between 2000 and 2009 at a medical centre in northern Taiwan. CRC status and survival status were determined until December 2010. Incidence data from the general population were retrieved from the Taiwan Cancer Registry. Outcome measures were defined as standardized incidence ratio and the incidence rate per 100,000 person-years. RESULTS: This study included 2294 patients, of whom 1194 (52%) had K. pneumoniae infection. During the follow-up period, 54 (2.3%) patients were diagnosed with CRC, corresponding to an overall incidence rate of 669.1 (95% CI, 490.7-847.6) per 100,000 person-years. The adjusted hazard ratio of CRC was 2.68 times greater for patients with K. pneumoniae PLA than for those with non-K. pneumoniae PLA (95% CI, 1.40-5.11). CONCLUSION: Patients with K. pneumoniae PLA had a significantly higher rate of subsequent CRC than did patients with non-K. pneumoniae PLA. Colonoscopy is recommended to detect occult colonic malignancy in patients with PLA, particularly for patients over 60 years of age and with K. pneumoniae.

First Report of the Cyst Nematode (Heterodera elachista) on Rice in Hunan Province, China.

During a survey for the cyst nematodes (Heterodera elachista) from May to June of 2011, cyst nematodes were detected in hilly rice fields in five counties (Changsha, Pingjiang, Hengdong, Shaoyang, and Xiangxiang) of Hunan Province, China. Cyst nematodes obtained from soil samples and harvested rice root samples at these five locations had uniform morphological and molecular characteristics. Cysts (n = 20) had the following characteristics: spherical to lemon shaped, vulval cone ambifenestrate, vulval bridge narrow, medium sized underbridge, with a few dark brown bullae, body length (not including the neck) ranging from 354 to 586 µm (mean = 438.9 µm, st. dev. = 63.7); body width ranged from 283 to 495 µm (354.5, 60.1); fenestrate length of 30 to 50 µm (37.4, 5.0) and width of 25 to 47.5 µm (35.1, 7.1); underbridge length from 70 to 95 µm (83.4, 8.2); and vulval slit length from 30.3 to 55.5 µm (40.3, 9.1). J2 (n = 20) had the following characteristics: body length ranging from 404 to 525 µm (mean of 461.6 µm, st. dev. = 34.5); stylet length from 20 to 25 µm (22.5, 1.1) with rounded knob; tail length of 60 to 87.5 µm (67.3, 6.9); and hyaline terminal tail ranged from 30 to 50 µm (37.5, 6.4); lateral field with three lines. The mean and range of J2 were longer than those reported for H. elachista by Nobbs et al. (1) and Tanha et al. (4), but other morphological character values were within the range of those reported (4). DNA from a single cyst was extracted, the rDNA-internal transcribed spacer (ITS) and D2/D3 fragments of the 28S RNA were amplified with universal primers TW81 and AB28, D2A and D3B, respectively. Five ITS sequences (JN202913, JN202914, JN202915, JN202916, and JN202917) and five D2/D3 sequences (JN202918, JN202919, JN202920, JN202921, and JN202922) from nematode samples collected in Changsha, Hengdong, Shaoyang, Pingjiang, and Xiangxiang, respectively, were submitted to GenBank. These ITS sequences were remarkably similar to each other and exhibited 98.6 to 99.3% similarity with that of H. elachista isolate from Iran (AF498391), and 98.8 to 99.4% similarity with that of H. elachista isolates from Ningxia Province, China (HM560778 and HM560779). The D2/D3 sequences exhibited 99.7 to 100% similarity with that of H. elachista isolates from Ningxia Province, China (HM560842 and HM560843). These characteristics indicated that the five populations were H. elachista belonging to the 'cyperi' group (1,2). In glasshouse evaluations of the pathogenicity of these isolates, 500 second-stage juveniles were inoculated onto five 20-day-old seedlings of rice (Weiyou No.227) in 4.5-cm diameter 30-cm high tubes with six replicates. After 8 weeks, stunting and reduction of leaf length were observed and cysts were extracted from dried soil of each tube using sieves. Brown cysts (92 to 204) and white females (14 to 40) were obtained from inoculated rice from each tube. H. elachista can decrease yield by 7 to 19% and has the most severe impact during the later stages of plant growth (3). H. elachista has been previously identified from rice fields in Japan and Iran (3). To our knowledge, this is the first report of H. elachista on rice in Hunan Province, China. References: (1) J. M. Nobbs et al. Fundam. Appl. Nematol. 15:551, 1992. (2) S. A. Subbotin et al. Mol. Phylogenet. Evol. 21:1, 2001. (3) S. A. Subbotin et al. Systematics of Cyst Nematodes (Nematoda: Heteroderinae). Volume 8 Part B. Brill, Leiden, the Netherlands, 2010. (4) M. Z. Tanha et al. Nematology 5:99, 2003.

In vitro activities of doripenem and other carbapenems against clinically important bacteria isolated in intensive care units: nationwide data from the SMART Programme.

This nationwide surveillance of clinically important bacteria from the intensive care units (ICUs) of major teaching hospitals throughout Taiwan investigated the susceptibilities to doripenem and other comparator carbapenems from September through November 2005. Minimum inhibitory concentrations (MICs) were determined for 1,311 clinical isolates using the broth microdilution method according to Clinical and Laboratory Standards Institute (CLSI) 2005 guidelines. Doripenem showed similar (within four-fold difference of MICs) in vitro activity to meropenem for Enterobacteriaceae and probably comparable activity to meropenem against important nosocomial non-fermentative Gram-negative bacilli (NFGNBs), including Pseudomonas aeruginosa, Acinetobacter baumannii and Burkholderia cepacia. Among the four carbapenems analysed, doripenem and meropenem exhibited better in vitro activity than imipenem or ertapenem against extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli isolates. However, the meropenem MIC(90) against ESBL-producing K. pneumoniae isolates was 2 microg/ml. Besides, doripenem with the MIC(90) of 0.5 microg/ml to Streptococcus pneumoniae possibly suggested its potential therapeutic effect regarding community-acquired pneumonia. Because of the heavy resistance burden in Taiwan, closely monitoring the evolutionary trend of carbapenem susceptibilities against clinically important pathogens is crucial in the future.

Nationwide surveillance of antimicrobial resistance among Enterobacteriaceae in intensive care units in Taiwan.

To determine the antimicrobial resistance profiles among clinical isolates of Enterobacteriaceae in Taiwanese intensive care units (ICUs), a national surveillance of antibiotic resistance among important Enterobacteriaceae was conducted from September 2005 through November 2005 at the ICUs of ten major teaching hospitals in Taiwan. A total of 574 Enterobacteriaceae isolates recovered from various clinical samples of our ICU patients were submitted for in vitro test. Minimum inhibitory concentrations (MICs) of these isolates to 18 antimicrobial agents were determined by the broth microdilution method. The prevalences of Enterobacteriaceae isolates with phenotypic extended-spectrum beta-lactamase (ESBL) production were 26% in Klebsiella pneumoniae, 16% in Serratia marcescens, 14% in Escherichia coli, and 13% in Proteus mirabilis, in which a significantly rising prevalence of ESBL production among K. pneumoniae was noted (p = 0.002) when compared with a previous Taiwanese survey in 2000. Heterogeneous resistance to various fluoroquinolones was found among our Enterobacteriaceae isolates, except for Enterobacter cloacae. Emergence of ertapenem-resistant isolates of E. coli, K. pneumoniae, E. cloacae, and S. marcescens was noted. Gradually increasing rates of drug-resistant Enterobacteriaceae were noted in Taiwanese ICUs. Periodic surveillance of the evolutionary trend of antimicrobial resistance among ICU isolates is crucial for starting appropriately empirical antimicrobial therapy in the future.

Nationwide surveillance of antimicrobial resistance among Haemophilus influenzae and Streptococcus pneumoniae in intensive care units in Taiwan.

A nationwide susceptibility surveillance of Streptococcus pneumoniae and Haemophilus influenzae isolates collected from patients treated at the intensive care units (ICUs) of ten Taiwanese major teaching hospitals was conducted from September 2005 through November 2005. High rates of resistance (intermediate/resistant) of S. pneumoniae to penicillin (85% resistance), ceftriaxone (46%/20%), and cefepime (43%/15%) by meningitis criteria, and in contrast, non-susceptibilities (intermediate/resistant) to penicillin (0%/0%), ceftriaxone (20%/0%) and cefepime (15%/0%) by non-meningitis criteria were noted (p values < 0.05) by the Clinical and Laboratory Standards Institute 2008. Resistant rate of S. pneumoniae to azithromycin was also high (63%). S. pneumoniae isolates were significantly more susceptible to ertapenem (87%) than to imipenem (39%) and meropenem (44%) (p values < 0.05). Rates of non-susceptibilities of H. influenzae isolates to ampicillin and cefaclor were high (55% and 45%, respectively). No beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae isolates were found. Imipenem has a notably higher MIC(90) value (8 microg/ml) for H. influenzae than that of the other two carbapenems. Tigecycline showed good in vitro activities against these two respiratory pathogens. High rates of resistance among isolates of S. pneumoniae and H. influenzae continue to exist in the ICUs of Taiwan.

Efficacy of point-of-entry copper--silver ionisation system in eradicating Legionella pneumophila in a tropical tertiary care hospital: implications for hospitals contaminated with Legionella in both hot and cold water.

A medical centre in Southern Taiwan experienced an outbreak of nosocomial Legionnaires' disease, with the water distribution system thought to be the source of the infection. Even after two superheats and flush, the rate of Legionella positivity in distal sites in hospital wards and intensive care units (ICUs) was 14% and 66%, respectively. Copper-silver ionisation was therefore implemented in an attempt to control Legionella colonisation in both hot- and cold-water systems. Environmental cultures and ion concentration testing were performed to evaluate the efficacy of ionisation. When the system was activated, no significant change in rate of Legionella positivity in the hospital wards (20% vs baseline of 30%) and ICUs (28% vs baseline of 34%) of the test buildings over a three-month period was found, although all Legionella positivity rates were below 30%, an arbitrary target for Legionnaires' disease prevention. When ion concentrations were increased from month 4 to month 7, however, the rate of Legionella positivity decreased significantly to 5% (mean) in hospital wards (P=0.037) and 16% (mean) in ICUs (P=0.037). Legionella positivity was further reduced to 0% in hospital wards and 5% (mean) in ICUs while 50% sites were still positive for Legionella in a control building. Although Legionella was not completely eradicated during the study period, no culture- or urine-confirmed hospital-acquired Legionnaires' disease was reported. Ionisation was effective in controlling Legionella for both hot and cold water, and may be an attractive alternative as a point-of-entry systematic disinfection solution for Legionella.

Inappropriate use of antibiotics and the risk for delayed admission and masked diagnosis of infectious diseases: a lesson from Taiwan.

BACKGROUND: Antibiotic resistance is a serious problem worldwide. It is particularly alarming in Taiwan and other countries of the Pacific Rim, where antimicrobial drugs are used excessively. OBJECTIVE: To determine whether use of antimicrobial drugs before coming to an emergency department was associated with delayed admission or masked or missed diagnoses at a large general hospital in Taiwan. METHODS: Antimicrobial activity in urine (AAU) was determined in all patients seen in the emergency department during a 3-month study. A physician, unaware of the results of the urine tests, reviewed the medical charts of patients who were admitted to the hospital to determine whether admission was delayed for at least 7 days or the diagnosis was masked or missed. RESULTS: Of the 1182 patients, 444 were admitted to the hospital. In 220 patients (49.5%), AAU was detected. There was no significant difference in AAU between patients with or without an infectious disease (53.0% vs 46.3%, respectively; P =.41). For patients with infection, 34.8% of those with AAU had a delayed admission, compared with only 21.6% without AAU (relative risk [RR], 1.61; 95% confidence interval [CI], 1.03-2.52; P =.03). For patients without infection, 36.2% of those with AAU had a delayed admission compared with 31.1% without AAU (RR, 1.16; 95% CI, 0.81-1.68; P =.64). For patients with infection, 48.7% of those with AAU had a masked or missed diagnosis, compared with 25.5% without AAU (RR, 1.91; 95% CI, 1.30-2.80; P<.001). For patients without infection, 27.6% of those with AAU had a masked or missed diagnosis compared with 14.8% without AAU (RR, 1.87; 95% CI, 1.11-3.17; P =.02). CONCLUSION: Use of antimicrobial drugs before coming to an emergency department was associated with a significantly increased risk for delayed and masked or missed diagnoses of infectious diseases and missed diagnosis of noninfectious diseases.

Detection of antimicrobial activity in urine for epidemiologic studies of antibiotic use.

Antibiotic resistance is the inevitable consequence of the selective pressure of antimicrobial drug use and the adaptive plasticity of the microorganisms. Excessive and irrational use of antimicrobial drugs is a problem in all countries. It is particularly troublesome in developing countries where there is a heavy burden of infectious diseases. This study was designed to determine whether detection of antimicrobial activity in the urine might be a useful tool for epidemiologic studies of the interaction between antibiotic use and resistance in developing countries. A laboratory marker is necessary because the history of antimicrobial drug use may be unreliable. Serial specimens or spontaneously voided urine were obtained from healthy volunteers given a single oral dose of commonly used antimicrobial drugs. Urine was also obtained from hospitalized patients the morning after the last dose of an antimicrobial drug and from untreated controls. Assays were performed with standard American Type Culture Collection (Rockville, MD) stains of Bacillus stearothermophilus, Escherichia coli, and Streptococcus pyogenes. Antimicrobial activity could not be detected in pretreatment urine. After a single oral dose, the beta lactam antibiotics and erythromycin could be detected for about 12 to 24 hours, whereas clindamycin, tetracycline, trimethoprim/sulfamethoxazole, and ciprofloxacin could be detected for 48 or more hours. In hospitalized patients, receiving multiple drugs, the following were the sensitivity and specificity for detection of antimicrobial activity: for B. stearothermophilus, 100.0% and 85.9%, respectively; for S. pyogenes, 94.9% and 94.9%, respectively; and for E. coli, 71.8% and 98.7%, respectively. The combination of E. coli and Streptococcus pyogenes exhibited a sensitivity of 97.4% and specificity of 94.9%. Detection of antimicrobial activity in urine is a promising method to determine antimicrobial drug use in epidemiologic studies, particularly in populations in which drug use history is unreliable.

Multicenter surveillance of antimicrobial resistance of major bacterial pathogens in intensive care units in 2000 in Taiwan.

A susceptibility surveillance study of 1,274 bacterial isolates recovered from various clinical specimens from patients in intensive care units (ICUs) of five major teaching hospitals was carried out from March, 2000, to June, 2000, in Taiwan. This study demonstrated a high rate (66%) of oxacillin resistance in Staphylococcus aureus (ORSA), a high rate of nonsusceptibility to penicillin (intermediate, 50% and highly resistant, 8%), and high rates of cefotaxime nonsusceptibility for S. pneumoniae (intermediate, 29% and resistant, 4%), Enterobacter cloacae (57%), Serratia marcescens (34%), and Citrobacter freundii (60%). High rate of ceftazidime nonsusceptibility for Pseudomonas aeruginosa (22%), and high rates of imipenem nonsusceptibility for P. aeruginosa (15%) and Acinetobacter baumannii (22%) were also found. The percentage (11.9%) of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli was greater than that (11.3%) for Klebsiella pneumoniae. Rates of quinupristin-dalfopristin nonsusceptibility for S. pneumoniae (42%), Enterococcus faecium (71%), and ORSA (39%) were high, but no vancomycin-resistant enterococci were found in this study. The resistance rates of some pathogen varied by institution or type of ICUs. Surveillance for antimicrobial resistance among bacterial pathogens in hospitals, particularly in ICU settings with a preexisting higher resistance burden, is mandatory in establishing and/or modifying guidelines for empirical treatment of severe infections in ICU patients caused by these antimicrobial-resistant pathogens.

Endoscopic 13C-urea breath test for the diagnosis of Helicobacter pylori infection.

BACKGROUND: Endoscopic 13C-urea breath test may avoid contamination of oral urease and rapidly discriminate Helicobacter pylori-positive and Helicobacter pylori-negative patients. AIMS: To compare the accuracy of endoscopic 13C-urea breath test with conventional invasive methods in diagnosis of Helicobacter pylori infection. PATIENTS: One hundred patients who attended for routine upper gastrointestinal endoscopy were included. METHODS: 13C-urea was applied to the stomach through the working channel of endoscope at the end of endoscopic examination. Breath samples were collected before endoscopy and 2, 4, 6, 8, 10 min after consumption of 100 or 50 mg 13C-urea. Helicobacter pylori infection was defined as those with positive culture or positive results of both histology and CLO test. RESULTS: The accuracy of 100 mg endoscopic 13C-urea breath test was significantly higher than that of culture and CLO test (100% vs. 88% and 92%, p = 0.02 and 0.03, respectively). The accuracy of 50 mg endoscopic 13C-urea breath test was higher than that of histology and CLO test (98% vs. 90% and 96%, respectively), although the differences were not statistically significant. CONCLUSIONS: Endoscopic 13C-urea breath test has a higher accuracy compared with biopsy-based modalities. It may be a good choice to diagnose Helicobacter pylori infection if endoscopy is indicated for a dyspeptic patient.

Comparison of the BACTEC MGIT 960 and BACTEC 460TB systems for detection of mycobacteria in clinical specimens.

The reliability of the Mycobacteria Growth Indicator Tube (MGIT) 960 system for rapid detection of mycobacteria in clinical specimens was evaluated and compared to the radiometric method (BACTEC 460TB) and to mycobacterial culture on Lowenstein-Jensen (LJ) medium. Clinical specimens (n = 590) were tested without selection. A total of 121 (20.5%) isolates of mycobacteria were recovered; 98 (81.0%) of them were recovered with the BACTEC 460TB system, 86 (71.1%) were recovered with the BACTEC MGIT 960 system, and 55 (45.5%) were recovered with LJ medium (MGIT 960 versus BACTEC 640TB, p >0.05; MGIT 960 or BACTEC 460TB versus LJ, p <0.001). The mean time to detection (TTD) was 18 da for BACTEC 460 TB, and 13 da for BACTEC MGIT 960. The mean time to detection in each system, based upon data where both systems were culture positive, was significantly different (16.6 da for BACTEC 460TB and 13 da for BACTEC MGIT 960, p<0.001). The contamination rate of the BACTEC MGIT 960 system was 13.2%, which was intermediate between the BACTEC 460TB system (11.7%) and the LJ medium (14.7%). These data indicate that the fully automated MGIT 960 system is an accurate, non-radiometric alternative to the BACTEC 460TB method for rapid detection of mycobacteria in a clinical setting.

Line probe assay for rapid detection of mutations in the rpoB gene of Mycobacterium tuberculosis.

Detection of mutations in the rpoB gene of Mycobacterium tuberculosis has been reported to be an accurate predictor of rifampin resistance. DNA sequence analysis and screening methods such as single-strand conformation polymorphism analysis and dideoxy fingerprinting are labor-intensive, expensive, or yield results that may prove difficult to interpret. We evaluated the accuracy of a commercial line probe assay for rapid identification and characterization of mutations in the rpoB gene in 72 isolates of M. tuberculosis, including 50 rifampin-resistant and 22 rifampin-susceptible strains. Ten distinct rpoB mutations were identified. Concordances with automated sequencing results and phenotypic rifampin susceptibility testing results were 99% and 93%, respectively. The results demonstrate the line probe assay to be a rapid (as short as 1 day) and informative tool for the early detection and characterization of rpoB mutations associated with rifampin resistance in a clinical laboratory setting.

Dideoxy fingerprinting for rapid screening of rpoB gene mutations in clinical isolates of Mycobacterium tuberculosis.

Rifampin is a key component of therapeutic regimens for tuberculosis control, and a marker for multidrug resistance of Mycobacterium tuberculosis. Mutations responsible for conferring rifampin resistance in M. tuberculosis are known to occur in a 69-bp region of the rpoB gene. In this study, we assessed the accuracy of dideoxy fingerprinting (ddF), a hybrid technique employing elements of dideoxy sequencing and single-strand polymorphism analysis, for rapid screening of rifampin resistance in clinical isolates of M. tuberculosis. This technique was used to analyze 72 M. tuberculosis isolates. The results were compared with those of automated dideoxy sequencing and the antibiotic resistance profile (determined with the BACTEC system). Of the 72 isolates, 50 were rifampin resistant. The ddF findings were completely consistent with those of dideoxy sequencing in all isolates. In 68 (94%) isolates, the ddF findings were consistent with the rifampin resistance status determined with the BACTEC system; all four isolates with inconsistent results had no mutation in the 69-bp region, but were resistant to rifampin. Our findings suggest that ddF accurately detects mutations in the rifampin resistance-associated 69-bp region of the rpoB gene in clinical isolates of M. tuberculosis, and may be a valuable screening tool for rifampin resistance.

Evaluation of polymerase chain reaction-restriction enzyme analysis of mycobacteria cultured in BACTEC 12B bottles.

Polymerase chain reaction with restriction enzyme analysis (PRA) was first tested on 15 reference strains and 50 subcultured clinical isolates of mycobacteria according to the reference algorithm by Telenti et al [1]. Next, we evaluated the application of this method to 108 isolates from liquid media (BACTEC 12B). Of them, 15 M. tuberculosis complex and 81 mycobacteria other than tuberculosis (MOTT) had comparable results with both PRA and the BACTEC 460 TB systems. However, seven M. tuberculosis complex and three potentially pathogenic MOTT were identified by PRA rather than the BACTEC TB system. PRA seems to be an efficient method for the identification of mycobacteria to the species level and a good aid to detect potentially pathogenic mycobacteria, especially in mixed mycobacterial cultures.

Serratia marcescens bacteremia.

Serratia marcescens bacteremia has become ubiquitous recently. S. marcescens bacteremia, either hospital- or community-acquired, can no longer be treated as insignificant. We reviewed 23 episodes of S. marcescens bacteremia in 1985. Among them, 17 patients (74%) were hospital-acquired infections, while 6 (26%) were community-acquired. Nine patients died, and the case fatality rate was 39%. Eleven patients (48%) had no clinically apparent source of infection, 5 (22%) had urinary tract infection, 3 (13%) had pneumonia, 2 (9%) had biliary tract infection, 1 (4%) had intra-abdominal infection, and 1 (4%) had skin and soft-tissue infection. Nosocomial isolates are often resistant to many antibiotics. Amikacin and the beta-lactamase-stable (third generation) cephalosporins are superior to gentamicin in the treatment of nosocomial S. marcescens bacteremia. We here emphasize that the awareness and treatment of S. marcescens bacteremia in daily clinical practice is unequivocally critical.

Streptococcal toxic shock syndrome in southern Taiwan.

This report outlines our experience with streptococcal toxic shock syndrome (STSS) at the Veterans General Hospital-Kaohsiung during the period October 1990 to November 1993. Group A streptococci were isolated from blood or normally sterile tissue in association with hypotension and multi-organ failure in the eight cases studied. A primary focus of infection was identified in seven cases, including pneumonia (1), septic arthritis (1) and soft-tissue infections (5). The remaining patient suffered from hyperglycemic hyperosmolar non-ketotic coma and Group A streptococcal bacteremia, without an obvious focus of infection. There were four cases of bacteremia. Clinical complications included acute renal failure in all eight cases, disseminated intravascular coagulation in five cases, liver involvement in two cases, adult respiratory distress syndrome in one case and soft-tissue necrosis in five cases. All isolates were sensitive to penicillin, and most patients were treated with intravenous penicillin G, with or without other antibiotics (gentamicin or clindamycin). Of the six patients with soft-tissue infection, two underwent amputation of the infected limb, and one patient underwent sono-guided pigtail drainage of psoas muscle abscess. Three of the patients died. STSS may be uncommon in Taiwan, but it is not rare. Early recognition of STSS (facilitated by Gram stain and culture), prompt debridement and drainage, and adequate antibiotic treatment with penicillin or clindamycin, or both, are necessary for control of such lethal infections.

Melioidosis: two indigenous cases in Taiwan.

We report the first two indigenously acquired cases of melioidosis in Taiwan, diagnosed by positive culture and biochemically identified using the ID 32 GN system (BioMerieux Vitek Inc, Hazelwood, MO, USA). The first patient was a 75-year-old Chinese woman who had not travelled abroad since her arrival from mainland China (San-Tung province) 47 years ago. She presented with spontaneous bacterial peritonitis and hepatitis C-related liver cirrhosis with septic shock. Burkholderia pseudomallei (formerly Pseudomonas pseudomallei) was isolated from cultures of both blood and ascites fluid. The second patient, a 70-year-old Chinese man, presented with right lower lobar pneumonia complicated with empyema and septic shock. Blood cultures grew B. pseudomallei. Both patients had underlying diabetes mellitus; one also had liver cirrhosis and chronic renal failure, while the other had a renal stone. The first patient died of refractory septic shock prior to diagnosis. The second patient survived with the use of intravenous ceftazidime for 30 days, followed by oral amoxicillin-clavulanic acid for a further 3 months. These cases serve as a reminder to clinical physicians that melioidosis is now no longer exclusive to patients with a history of travel to endemic areas. A high index of clinical suspicion is required for early diagnosis and treatment in order to reduce the mortality and improve clinical outcome.

Silibinin inhibits VEGF secretion and age-related macular degeneration in a hypoxia-dependent manner through the PI-3 kinase/Akt/mTOR pathway.

BACKGROUND AND PURPOSE: Hypoxia-mediated neovascularization plays an important role in age-related macular degeneration (AMD). There are few animal models or effective treatments for AMD. Here, we investigated the effects of the flavonoid silibinin on hypoxia-induced angiogenesis in a rat AMD model. EXPERIMENTAL APPROACH: Retinal pigmented epithelial (RPE) cells were subjected to hypoxia in vitro and the effects of silibinin on activation of key hypoxia-induced pathways were examined by elucidating the hypoxia-inducible factor-1 alpha (HIF-1α) protein level by Western blot. A rat model of AMD was developed by intravitreal injection of VEGF in Brown Norway rats, with or without concomitant exposure of animals to hypoxia. Animals were treated with oral silibinin starting at day 7 post-VEGF injection and AMD changes were followed by fluorescein angiography on days 14 and 28 post-injection. KEY RESULTS: Silibinin pretreatment of RPE cells increased proline hydroxylase-2 expression, inhibited HIF-1α subunit accumulation, and inhibited VEGF secretion. Silibinin-induced HIF-1α and VEGF down-regulation required suppression of hypoxia-induced phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin (mTOR) pathway. In the rat model of AMD, silibinin administration prevented VEGF- and VEGF plus hypoxia-induced retinal oedema and neovascularization. CONCLUSION AND IMPLICATIONS: The effects of silibinin, both in vitro and in vivo, support its potential as a therapeutic for the prevention of neovascular AMD.