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The effectiveness of different treatment processes on assimilable organic carbon (AOC) removal and bacterial diversity variations was evaluated in a water treatment plant. The van der Kooij technique was applied for AOC analysis and responses of bacterial communities were characterized by the metagenomics assay. Results show that the AOC concentrations were about 93, 148, 43, 51, 37, and 38 μg acetate-C/L in effluents of raw water basin, preozonation, rapid sand filtration (RSF), ozonation, biofiltration [biological activated carbon (BAC) filtration], and chlorination (clear water), respectively. Increased AOC concentrations were observed after preozonation, ozonation, and chlorination units due to the production of biodegradable organic matters after the oxidation processes. Results indicate that the oxidation processes were the main causes of AOC formation, which resulted in significant increases in AOC concentrations (18-59% increment). The AOC removal efficiencies were 47, 28, and 60% in the RSF, biofiltration, and the whole system, respectively. RSF and biofiltration were responsible for the AOC treatment and both processes played key roles in AOC removal. Thus, both RSF and biofiltration processes would contribute to AOC treatment after oxidation. Sediments from the raw water basin and filter samples from RSF and BAC units were collected and analyzed for bacterial communities. Results from scanning electron microscope analysis indicate that bacterial colonization was observed in filter materials. This indicates that the surfaces of the filter materials were beneficial to bacterial growth and AOC removal via the adsorption and biodegradation mechanisms. Next generation sequencing analyses demonstrate that water treatment processes resulted in the changes of bacterial diversity and community profiles in filters of RSF and BAC. According to the findings of bacterial composition and interactions, the dominant bacterial phyla were Proteobacteria (41% in RSF and 56% in BAC) followed by Planctomycetes and Acidobacteria in RSF and BAC systems, which might affect the AOC biodegradation efficiency. Results would be useful in developing AOC treatment and management processes in water treatment plants., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Utilization of bacterial volatilization can be problematic to remediate mercury (Hg)-contaminated soils because most of the Hg in soils is bound to soil particles. The objective of this study was to develop a two-stage system (chemical extraction followed by microbial reduction) for Hg-contaminated soil remediation. The tasks were to (1) select the extraction reagents for Hg extraction, (2) assess the effects of extraction reagents on the growth of Hg-reducing bacterial strains, and (3) evaluate the effectiveness of Ca 2+ and Mg 2+ addition on merA gene (Hg reductase) induction. Bacterial inhibition was observed with the addition of 0.1 M ethylenediaminetetraacetic acid or citric acid. Up to 65% of Hg was biotransformed (Hg concentration = 69 mg/kg) from the soils after a 24 h extraction using 0.5 M ammonium thiosulfate. Ca 2+ and Mg 2+ were selected because they have the same electric charge as Hg and the studied groundwater contained high concentrations of Ca 2+ and Mg 2+ . Results showed that the addition of 200 mg/L Ca 2+ or 650 mg/L Mg 2+ could reach effective merA induction. In the two-stage experiment, 120 mg/kg Hg-contaminated soils were extracted with 2 rounds of extraction processes for 10 h using 0.5 M ammonium thiosulfate. Approximately 77% of Hg was extracted from the soils after the first-step extraction process. Up to 81% of Hg 2+ was transformed from the washing solution via the biotransformation processes with Enterobacter cloacae addition and Ca 2+ and Mg 2+ supplementation. The two-stage remedial system has the potential to be developed into a practical technology to remediate Hg-contaminated sites., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A long-lasting emulsified colloidal substrate (LECS) was developed for continuous carbon and nanoscale zero-valent iron (nZVI) release to remediate trichloroethylene (TCE)-contaminated groundwater under reductive dechlorinating conditions. The developed LECS contained nZVI, vegetable oil, surfactants (Simple Green™ and lecithin), molasses, lactate, and minerals. An emulsification study was performed to evaluate the globule droplet size and stability of LECS. The results show that a stable oil-in-water emulsion with uniformly small droplets (0.7 μm) was produced, which could continuously release the primary substrates. The emulsified solution could serve as the dispensing agent, and nZVI particles (with diameter 100-200 nm) were distributed in the emulsion evenly without aggregation. Microcosm results showed that the LECS caused a rapid increase in the total organic carbon concentration (up to 488 mg/L), and reductive dechlorination of TCE was significantly enhanced. Up to 99% of TCE (with initial concentration of 7.4 mg/L) was removed after 130 days of operation. Acidification was prevented by the production of hydroxide ion by the oxidation of nZVI. The formation of iron sulfide reduced the odor from produced hydrogen sulfide. Microbial analyses reveal that dechlorinating bacteria existed in soils, which might contribute to TCE dechlorination., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Our experimental results demonstrate that full-field hard-X-ray microscopy is finally able to investigate the internal structure of cells in tissues. This result was made possible by three main factors: the use of a coherent (synchrotron) source of X-rays, the exploitation of contrast mechanisms based on the real part of the refractive index and the magnification provided by high-resolution Fresnel zone-plate objectives. We specifically obtained high-quality microradiographs of human and mouse cells with 29 nm Rayleigh spatial resolution and verified that tomographic reconstruction could be implemented with a final resolution level suitable for subcellular features. We also demonstrated that a phase retrieval method based on a wave propagation algorithm could yield good subcellular images starting from a series of defocused microradiographs. The concluding discussion compares cellular and subcellular hard-X-ray microradiology with other techniques and evaluates its potential impact on biomedical research., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Aims: To develop a microbial strain producing poly(3-hydroxybutyrate) [P(3HB)], in the absence of antibiotic supplementation (normally required to stabilize a recombinant plasmid), by constructing a recombinant Escherichia coli strain with phaCAB and vgb integrated into the chromosome., Methods and Results: The polyhydroxyalkanoate (PHA) synthesis operon (phaCAB) and the bacterial haemoglobin gene (vgb) were integrated downstream of nlpB (novel lipoprotein B) in E. coli K12, via homologous recombination, to form a recombinant strain, termed YH100. VHb encoded by the vgb gene was successfully expressed in YH100, as confirmed by Western blotting. P(3HB) synthesis by the YH100 strain grown in the absence of antibiotic was analysed by transmission electron microscopy. The yield of P(3HB) is 208 mg g(-1) . The thermal stability of P(3HB) produced from YH100 was similar to that of commercial P(3HB). Further, the polydispersity index (PDI) of the P(3HB) polymer derived from YH100 was 1·37, indicating that polymer uniformity was greater than that of commercial P(3HB), which had a PDI of 1·47., Conclusions: We successfully constructed a recombinant E. coli strain expressing exogenous genes, specifically phaCAB from Cupriavidus necator and vgb from Vitreoscilla stercoraria, integrated into the downstream of chromosomal dapA-nlpB locus. P(3HB) was stably produced by this strain, without any need for antibiotic supplementation to stabilize a recombinant plasmid at least for 48h., Significance and Impact of the Study: We report a genetic locus, the downstream of the nlpB locus in E. coli, in which the transcription of the exogenous genes is driven by the dapA-nlpB promoter without the need for the addition of inducer and antibiotic., (© 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.)

A matrix-free, high sensitivity, nanostructured silicon surface assisted laser desorption/ionization mass spectrometry (LDI-MS) method fabricated by metal-assisted etching was investigated. Effects of key process parameters, such as etching time, substrate resistance and etchant composition, on the nanostructured silicon formation and its LDI-MS efficiency were studied. The results show that the nanostructured silicon pore depth and size increase with etching time, while MS ion intensity increases with etching time to 300 s then decreases until 600 s for both low resistance (0.001-0.02Ωcm) and high resistance (1-100Ωcm) silicon substrates. The nanostructured silicon surface morphologies were found to directly affect the LDI-MS signal ion intensity. By characterizing the nanostructured silicon surface roughness using atomic force microscopy (AFM) and sample absorption efficiency using fluorescence microscopy, it was further demonstrated that the nanostructured silicon surface roughness was highly correlated to the LDI-MS performance., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Aim: To develop an approach to enhance polyhydroxybutyrate (PHB) production via the coexpressed phaCAB and vgb genes controlled by arabinose P(BAD) promoter in Escherichia coli., Method and Results: The polyhydroxyalkanoates (PHAs) synthesis operon, (phaCAB), from Ralstonia eutropha was overexpressed under the regulation of the arabinose P(BAD) promoter in Escherichia coli, and the vgb gene encoding bacterial haemoglobin from Vitreoscilla stercoraria (VHb) was further cloned at downstream of phaCAB to form an artificial operon. The cell dry weight (CDW), PHB content and PHB concentration were enhanced around 1.23-, 1.57-, and 1.93-fold in the engineered cell harbouring phaCAB-vgb (SY-2) upon 1% arabinose induction compared with noninduction (0% arabinose). Furthermore, by using a recombinant strain harbouring P(BAD) promoter-vgb along with native promoter-phaCAB construction, the effect of vgb expression level on PHB biosynthesis was positive correlation., Conclusions: The results exploit the possibility to improve the PHB production by fusing the genes phaCAB-vgb from different species under the arabinose regulation system in E. coli. It also demonstrates that increase in VHb level enhances the PHB production., Significance and Impact of the Study: We were successful in providing a new coexpressed system for PHB synthesis in E. coli. This coexpressed system could be regulated by arabinose inducer, and is more stable and cheaper than other induced systems (e.g. IPTG). Furthermore, it could be applied in many biotechnology or fermentation processes.

We present a patient with a history of clomipramine-induced serotonin syndrome 5 yr prior who developed serotonin syndrome after a single dose of meperidine. This report heightens appreciation of population at risk and also recognition of potential toxicity in meperidine.

The appearance of assimilable organic carbon (AOC), microbial regrowth, disinfection by-products (DBPs), and pipe corrosion in drinking water distribution systems are among those major safe drinking water issues in many countries. The water distribution system of Cheng-Ching Lake Water Treatment Plant (CCLWTP) was selected in this study to evaluate the: (1) fate and transport of AOC, DBPs [e.g., trihalomethanes (THMs), haloacetic acids (HAAs)], and other organic carbon indicators in the selected distribution system, (2) correlations between AOC (or DBPs) and major water quality parameters [e.g. dissolved oxygen (DO), free residual chlorine, and bacteria, and (3) causes and significance of corrosion problems of the water pipes in this system. In this study, seasonal water samples were collected from 13 representative locations in the distribution system for analyses of AOC, DBPs, and other water quality indicators. Results indicate that residual free chlorine concentrations in the distribution system met the drinking water standards (0.2 to 1 mg l(-1)) established by Taiwan Environmental Protection Administration (TEPA). Results show that AOC measurements correlated positively with total organic carbon (TOC) and UV-254 (an organic indicator) values in this system. Moreover, AOC concentrations at some locations were higher than the 50 microg acetate-C l(-1) standard established by Taiwan Water Company. This indicates that the microbial regrowth might be a potential water quality problem in this system. Higher DO measurements (>5.7 mg l(-1)) might cause the aerobic biodegradation of THMs and HAAs in the system, and thus, low THMs (<0.035 mg l(-1)) and HAAs (<0.019 mg l(-1)) concentrations were observed at all sampling locations. Results from the observed negative Langelier Saturation Index (LSI) values, higher Ryznar Stability Index (RSI) values, and high Fe3+ concentrations at some pipe-end locations indicate that highly oxidative and corrosive conditions occurred. This reveals that pipe replacement should be considered at these locations. These findings would be helpful in managing the water distribution system for maintaining a safe drinking water quality.

Aims: To develop an Aeromonas strain able to utilize inexpensive carbon sources such as starch for the synthesis of polyhydroxyalkanoates (PHA)., Methods and Results: A recombinant Aeromonas sp. (strain KC007-1) was constructed by introducing the PHB synthesis genes (phaCAB) into the bacterium. Strain KC001-R1 can not only use carbohydrate (including starch) for growth but also accumulate significant amounts of polyhydroxybutyrate (PHB) in the cells., Conclusions: One of the present focuses on PHA production has been on lowering the production costs. Starch is an example of an inexpensive carbohydrate for use in industrial production of PHA. We have demonstrated that by introducing the phaCAB operon into Aeromonas sp. allowed the bacterium able to accumulated PHB using this substrate., Significance and Impact of the Study: Aeromonas spp. are able to synthesize PHA using fatty acids as carbon source. Although good robust growth results with use of starch as sole carbon source for Aeromonas, PHA synthesis does not occur. Strain KC007-R1 showed the ability to accumulate PHA in relative high amount with both carbohydrates and fatty acids as carbon source, and can be cultivated to a significant amount of cell mass and hence is a potential strain for further development for industrial applications.

Ribosomal proteins are encoded by a gene family, members of which are overexpressed in human cancers. Many of them have been found, using oligonucleotide microarray hybridization, to be differentially expressed in the faeces of patients with various stages of colorectal cancer (CRC). The gene encoding ribosomal protein L19 (RPL19), a prognostic marker for human prostate cancer, is differentially expressed in CRC patients. Measurement of faecal RPL19 mRNA might improve prognostic prediction for CRC patients. Using quantitative real-time reverse transcription PCR, levels of RPL19 mRNA were detected in samples of colonic tissues from 44 CRC patients, in the faeces of 54 CRC patients and 15 controls, and in 11 colonic cell lines. Seven of 24 patients with late-stage CRC (Dukes' stages C and D) expressed over 2-fold more RPL19 in colonic tumour tissues than in corresponding normal tissues (P= 0.038). The mean faecal RPL19 mRNA levels of late-staged patients were higher than those of controls (P= 0.003) and early-staged patients (P= 0.008). Patients with both high serum levels of carcinoembryonic antigen (CEA; > 5 ng/mL) and high-faecal RPL19 mRNA (> or =0.0069) had higher risk (odds ratio, 8.0; P= 0.015) and lower overall 48-month survival (33.8 +/- 13.7%, P= 0.013). Oligonucleotide microarray hybridization analysis of faecal molecules identified gene transcripts differentially present in faeces. In conclusion, faecal RPL19 expression is associated with advanced tumour stages and addictive to serum CEA in predicting prognosis of CRC patients.

The Cheng-Ching Lake Water Treatment Plant (CCLWTP) is the main supplier of domestic water for the Greater Kaohsiung area, the second largest metropolis in Taiwan. Biological activated carbon (BAC) filtration is one of the major treatment processes in CCLWTP. The objectives of this study were to evaluate the effectiveness of BAC filtration on water treatment in the studied advanced water treatment plant and its capability on pollutants [e.g., AOC (assimilable organic carbon), bromide, bromate, iron] removal. In this study, water samples from each treatment process of CCLWTP were collected and analyzed periodically to assess the variations in concentrations of AOC and other water quality indicators after each treatment unit. Moreover, the efficiency of biofiltration process using granular activated carbon (GAC) and anthracite as the fillers was also evaluated through a column experiment. Results show that the removal efficiencies for AOC, bromide, bromate, and iron are 86% 100%, 17%, and 30% after the BAC filter bed, respectively. This indicates that BAC filtration plays an important role in pollutant removal. Results also show that AOC concentrations in raw water and effluent of the CCLWTP are approximately 143 and 16 microg acetate-Cl(-1), respectively. This reveals that the treatment processes applied in CCLWTP is able to remove AOC effectively. Results of column study show that the AOC removal efficiencies in the GAC and anthracite columns are 60% and 17%, respectively. Microbial colonization on GAC and anthracite were detected via the observation of scanning electron microscopic images. The observed microorganisms included bacteria (rods, cocci, and filamentous bacteria), fungi, and protozoa. Results from this study provide us insight into the mechanisms of AOC removal by advanced water treatment processes. These findings would be helpful in designing a modified water treatment system for AOC removal and water quality improvement.

Background: Many factors may influence the epidemiologic trend of adult bacterial meningitis (ABM). The objective of this study was to analyze recent epidemiologic trends of ABM in order to provide a better therapeutic strategy., Materials and Methods: The clinical features, laboratory data, and therapeutic outcomes of 181 ABM cases collected in the last 6.5 years (July 1999-December 2005) were analyzed. The results were compared with those of our previous study (202 cases, January 1986-June 1999)., Results: The 181 cases consisted of 130 men (age range: 18-82 years) and 51 women (age range: 18-78 years). Monomicrobial infection and mixed infection were found in 165 cases and 16 cases, respectively. A preceding postneurosurgical state was noted in 56.9% (103/181) of cases. Despite a decrease in incidence, Klebsiella pneumoniae (25.5%, 42/165) was still the most common pathogen. A marked increase of Acinetobacter meningitis (11.5%, 19/165) was noted, which replaced Pseudomonas meningitis as the second most common Gram-negative pathogen in ABM. A marked increase in staphylococcal infection, accounting for 23% (38/165) of all cases, was also noted, of which 76% (29/38) were methicillin-resistant strains. The therapeutic result showed a mortality rate of 30.3% (55/181). Significant prognostic factors included septic shock and age at infection., Conclusions: This study revealed a change in the epidemiologic trend of ABM, with an increase in the number of patients with a postneurosurgical state and a rising incidence of Acinetobacter and staphylococcal infections. Clinicians should pay greater attention to these changes, which may affect their management of ABM.

Background: Von Hippel-Lindau (VHL) disease is an autosomal dominant hereditary disorder associated with tumours and cysts in the central nervous system (CNS) and other visceral organs. Germline mutations in the VHL gene on chromosome 3p25-26 are considered the cause of this disease., Materials and Methods: We studied six patients with VHL disease and their relatives. Loss of heterozygosity (LOH) was determined by five flanking microsatellite polymorphic markers in the VHL locus. Multiplex ligation-dependent probe amplification (MLPA) and quantitative real-time polymerase chain reaction (qPCR) amplification were used to detect the genomic deletions. Single-strand conformation polymorphism (SSCP) analysis was applied to test for sequence variations., Results: Three germline deletions in the VHL gene (142.9, 53.3 and 3.3 kb) were found by MLPA. These deletions were defined clearly by qPCR analyses. The142.9 kb germline deletion was significantly associated with patients with CNS haemangioblastomas (P < 0.01 by Fisher's exact test), and one missense mutation (Gln209Arg) was detected from a patient with a pancreatic cyst in the same family. LOH was also detected from a patient with bilateral renal cell carcinomas., Conclusion: Diverse genetic conditions are associated with the clinical manifestations of VHL disease. Genomic deletions that can be detected by MLPA or qPCR are major causes for this syndrome. Missense mutations and LOH accompanying the disease lead to complex clinical symptoms and genotypic determination can facilitate a clinical diagnosis because of their strong association.

Aims: To develop an efficient approach using a combination of phenotypic and genotypic methods for isolation of environmental bacteria that produce mid-chain-length polyhydroxyalkanoates (mcl-PHAs)., Methods and Results: A viable-colony staining method using Nile red was used to screen for PHA-producing bacteria followed by a polymerase chain reaction (PCR) screen using primers to amplify the partial nucleic acid sequence of the phaC1 synthase gene for confirmation. Microbes containing lipophilic storage compounds isolated from environmental samples could readily be detected by the colony staining method. They were further examined by Sudan Black staining to highlight the inclusions inside the cells. These isolates were subsequently subjected to PCR analysis. As a result, more than a hundred strains were identified as PHA-positive isolates from this screening approach., Conclusions: These results conclusively demonstrate that environmental bacterial strains able to accumulate the PHAs could readily be obtained by this screening method., Significance and Impact of the Study: We propose a polyphasic approach using a combination of phenotypic and genotypic screening method to rapidly screen and identify bacteria able to produce significant amounts of mcl-PHAs from environment. This approach can be adopted as a rapid screen for micro-organisms able to accumulate PHAs to be used for potential manufacture and other industrial applications.

Background: To delineate the epidemiologic trend, clinical characteristics and therapeutic outcomes of bacterial meningitis in young adults in Southern Taiwan., Patients and Methods: Over a period of 18 years, 329 cases of culture-proven adult bacterial meningitis were identified at our hospital. Among these 329 cases, 62 were identified as young adults (< or = 40 years) and their clinical features, laboratory data and therapeutic outcomes were reviewed. The prognostic factors between fatal and non-fatal groups were compared., Results: The 62 young adults were 48 men and 14 women, aged 17-40 years. Thirty of the 62 patients belonged to nosocomial infection, and the other 32 belonged to community-acquired infection. A total of 74% (46/62) of the patients had a post-neurosurgical state as the underlying condition. Alcoholism (n = 8) was the most common underlying condition of the other 16 patients with spontaneous meningitis. Of these 62 patients, Klebsiella pneumoniae and Pseudomonas aeruginosa were the most common implicated gram-negative pathogens. During the late study period, there was an increase in coagulase-negative staphylococcus and Staphylococcus aureus infections. The therapeutic results of this group of patients are as follows: 13 patients died, 18 had full recovery and 31 had varying degrees of neurologic deficits. Impaired consciousness and thrombocytopenia were significant prognostic factors., Conclusion: A post-neurosurgical state is an important preceding event for young adults to develop bacterial meningitis. Of the implicated gram-negative pathogens, K. pneumoniae and P. aeruginosa are common; however, there has been an increase in staphylococcal infection in recent years. Therapeutic results of this specific group of patients showed that 20% (13/62) of the patients died, and 50% (31/61) of the patients in this study had neurologic deficits. However, the small case number and possible bias of case selection has limited the analytical conclusions of this study. Further large-scale studies are needed to delineate the clinical characteristics and therapeutic outcomes of bacterial meningitis in this specific group of patients.

T cells have been demonstrated to modulate ischemia-reperfusion injury (IRI) in kidney, lung, liver and intestine. The underlying mechanisms for T-cell engagement in IRI are unknown. We hypothesized that the T-cell receptor (TCR) plays a role in renal IRI, and examined the effects of TCR alpha/beta (alphabeta) and gamma/delta (gammadelta) deficiency on ischemic acute renal failure (ARF). TCR-specific deficiency in specific mice was confirmed by fluorescence-activated cell sorting analysis using monoclonal antibodies (Abs). IRI was induced by bilateral clamping of kidney pedicles for 30 min, followed by reperfusion. Serum creatinine and kidney histopathology were used to assess the severity of experimental ARF. TCR alphabeta-deficient mice were significantly protected from kidney dysfunction compared to wild-type (WT) littermates after IRI (P<0.05). Histologic analysis demonstrated a significant reduction in renal tubular injury in both TCR alphabeta- and gammadelta-deficient mice compared to WT mice postischemia. TCR alphabeta-deficient mice had reduced tumor necrosis factor-alpha and interleukin-6 protein expression in kidney tissue compared to WT mice at 24 h postischemia using a microbead-based protein detection platform. Relative protection from kidney IRI did not correlate with neutrophil and macrophage infiltration of kidney tissue. Thus, the TCR plays a direct but modest pathophysiological role in kidney IRI. These data suggest that alloantigen-independent activation in IRI can lead to engagement of antigen-specific molecules on T cells. Furthermore, given that the TCR is already a target for diagnostics and therapeutic strategies in immune diseases, these approaches can now be harnessed for IRI.

Methyl tert-butyl ether (MTBE) has been used as a gasoline additive to improve the combustion efficiency and to replace lead since 1978. Because it is widely used and it has been disposed inappropriately, MTBE has become a prevalent groundwater contaminant worldwide. In this study, two petroleum-hydrocarbon contaminated sites (Sites A and B) were selected to evaluate the occurrence and effectiveness of natural attenuation of MTBE at these two sites. Field investigation results indicate that the natural attenuation mechanisms of MTBE at both sites were occurring with the first-order attenuation rates of 0.0021 and 0.0048 1day(-1) at Sites A and B, respectively. Results also reveal that the intrinsic biodegradation pattern was the most important mechanism among the natural attenuation processes at both sites. Results from BIOSCREEN simulation suggest that biodegradation was responsible for 78 and 59% of MTBE mass reduction at Sites A and B, respectively. Investigation results show that MTBE plume at Site B could be effectively controlled via natural attenuation processes. However, MTBE plume at Site A has migrated to a farther downgradient area and passed the boundary line of the site. Thus, more active groundwater remedial technologies should be applied at Site A to protect the downgradient environment. Results from this study suggest that natural attenuation might be feasible to be used as a remedial option for the remediation of MTBE-contaminated site on the premise that (1) detailed site characterization has been conducted and (2) the occurrence and effectiveness of natural attenuation processes have been confirmed.

Background: We wanted to analyze the clinical characteristics and therapeutic outcomes of adult meningitis caused by coagulase-negative staphylococci (CoNS)., Patients and Methods: Over a period of 5 years (January 1999 to December 2003), 127 cases were identified as having adult culture-proven bacterial meningitis caused by a single pathogen. Of them, 14 cases with CoNS meningitis were enrolled, and their clinical characteristics and therapeutic outcomes were analyzed., Results: The 14 cases (median age 37.5; range 24-77 years old) included nine men and five women. With polynerase chain reaction sequencing of bacterial 16S r-RNA, 10 of the 14 CoNS strains were identified as Staphylococcus epidermidis infection, and the other four belonged to Staphylococcus haemolyticus. All 14 cases were in a postneurosurgical state with insertion of a ventriculoperitoneal shunt, external ventricular device or intrathecal port A as their underlying conditions, and 12 of the 14 patients contracted the infection nosocomially. Fever (86%), leukocytosis (79%), hydrocephalus (50%), consciousness disturbance (36%), and seizure (7%) were the major clinical manifestations. All the involved CoNS strains showed resistance to oxacillin but retained their susceptibility to vancomycin and linezolid. All 14 CoNS strains had positive mecA gene detection. With the removal of neurosurgical devices and intravenous vancomycin therapy, 86% (12/14) of the patients survived., Conclusion: CoNS meningitis accounted for 11% (14/127) of our adult bacterial meningitis. All adult CoNS meningitis patients had a disrupted barrier of the central nervous system as the underlying condition. S. epidermidis was the most common CoNS subtype involved. All involved CoNS strains were oxacillin resistant. The therapeutic result showed that adult CoNS meningitis had a mortality rate of 14% (2/14).

Microbiologically influenced corrosion (MC) of steel has been attributed to the activity of biofilms that include anaerobic microorganisms such as iron-respiring bacteria, yet the mechanisms by which these organisms influence corrosion have been unclear. To study this process, we generated mutants of the iron-respiring bacterium Shewanella oneidensis strain MR-1 that were defective in biofilm formation and/or iron reduction. Electrochemical impedance spectroscopy was used to determine changes in the corrosion rate and corrosion potential as a function of time for these mutants in comparison to the wild type. Counter to prevailing theories of MC, our results indicate that biofilms comprising iron-respiring bacteria may reduce rather than accelerate the corrosion rate of steel. Corrosion inhibition appears to be due to reduction of ferric ions to ferrous ions and increased consumption of oxygen, both of which are direct consequences of microbial respiration.

We compared the acute and long-term outcomes of stentings in coronary vessels > 3.0 mm, 3.0-2.5 mm, and < 2.5 mm. A total of 1,152 patients underwent coronary stenting was divided into three groups based on the reference vessel size. Group A consisted of 598 patients (667 lesions) with a reference vessel diameter > 3.0 mm, group B 485 patients (544 lesions) with a reference vessel diameter of 3.0-2.5 mm, and group C 114 patients (119 lesions) with a reference vessel diameter < 2.5 mm. The procedural success, stent thrombosis, and in-hospital cardiac event rate were similar in the three groups. At 6-month angiographic follow-up, the lesion restenotic rate was significantly higher in the small-vessel group (14%, 22%, and 26% in groups A, B, and C, respectively; P = 0.011). These differences appeared to result from a lesser acute gain and a lesser net gain in small-vessel group; the late luminal loss was similar in the three groups. During a follow-up duration of 28 +/- 3 months, group C patients had a significantly lower rate of event-free survival than the group A and B patients (71% vs. 85% and 82%; P = 0.002). Stepwise regression analysis demonstrated that complex lesion (P = 0.032) and long lesion (P = 0.046) are independent predictors of restenosis in very-small-vessel (< 2.5 mm) stenting. In conclusion, the acute results of stenting in small coronary arteries appear safe and feasible with a high procedural success rate and a low incidence of stent thrombosis. Stenting in patients with a small coronary artery appears to have a similar in-hospital cardiac event rate, but a higher angiographic restenosis rate and a lower event-free survival rate, compared to stenting in patients with a larger coronary artery. The predictors of restenosis in very-small-vessel stenting are complex lesions and long lesions. Cathet Cardiovasc Intervent 2001;53:314-322., (Copyright Wiley-Liss, Inc.)

Background/aims: In spite of the better efficiency of on-line hemodiafiltration (HDF) compared with conventional hemodialysis (HD), it is relatively expensive. The aim of this study was to assess the advantages in the biochemical, hemodynamic and clinical effects in uremic patients treated with on-line HDF and with different frequencies of combination high-flux HD., Methods: One hundred eleven patients were divided into four groups receiving different frequencies of on-line HDF (thrice, twice, once per week) and high-flux HD., Results: Hemodynamic parameters including maximum drop of systolic blood pressure, episodes of symptomatic hypotension and mean saline infusion volumes during dialysis were reduced when frequencies of on-line HDF were increased. Significant improvements in urea kinetic were observed when frequencies of on-line HDF were increased. On-line HDF significantly reduced the amount of erythropoietin needed and improved intra- and inter-dialysis symptoms, physical well-being, menstruation and skin pigmentation when frequency of HDF is increased to three time per week., Conclusion: On-line HDF offers a better cardiovascular stability and clinical improvement. Thrice weekly on-line HDF offers a significant benefit when compared with lower frequencies of HDF per week and high-flux HD.

To determine the prevalence of colonization by Corynebacterium ulcerans, we cultured samples from the cephalic implant-skin margin and pharynx of 26 rhesus macaques and one pig-tailed macaque. All but one of the samples from the cephalic implants yielded a mixed population of bacteria. C. ulcerans grew from the cephalic implants in 56% and from the pharynx in 3% of the implanted animals. We screened nine of these isolates for diphtheria toxin (DT) and phospholipase D (PLD). Polymerase chain reactions (PCR) failed to identify DT in any of the tested isolates, which also lacked DT activity in Elek tests. However, all nine isolates tested had PLD toxin activity as determined by conjoint hemolysis on sheep blood agar plates in the presence of equi factor (Rhodococcus equi). In addition, PCR assays and Southern blot hybridization confirmed the presence of pld in the isolates. The role of the PLD toxin in promoting colonization of cephalic implants by C. ulcerans is unknown. We found C. ulcerans to be a frequent contaminant of the cephalic implant-skin margin. Further studies are necessary to investigate the relative clinical importance of this organism and the efficacy of various implant maintenance protocols in preventing infection.

Helicobacter pullorum has been isolated from the feces and livers of poultry and is associated with human gastroenteritis. Discrimination of this organism from other enterohepatic Helicobacter species and Campylobacter species has proven difficult. H. pullorum from both avian and human clinical sources has DNA sequence homology and cytotoxic activity that represent a new member of the cytolethal distending toxin (CDT) family of bacterial toxins. CDT is a potential virulence factor in H. pullorum that may serve as a distinguishing phenotype and aid in identification of this organism in veterinary and human clinical samples.

The "altered Schaedler flora" (ASF) was developed for colonizing germfree rodents with a standardized microbiota. The purpose of this study was to identify each of the eight ASF strains by 16S rRNA sequence analysis. Three strains were previously identified as Lactobacillus acidophilus (strain ASF 360), Lactobacillus salivarius (strain ASF 361), and Bacteroides distasonis (strain ASF 519) based on phenotypic criteria. 16S rRNA analysis indicated that each of the strains differed from its presumptive identity. The 16S rRNA sequence of strain ASF 361 is essentially identical to the 16S rRNA sequences of the type strains of Lactobacillus murinis and Lactobacillus animalis (both isolated from mice), and all of these strains probably belong to a single species. Strain ASF 360 is a novel lactobacillus that clusters with L. acidophilus and Lactobacillus lactis. Strain ASF 519 falls into an unnamed genus containing [Bacteroides] distasonis, [Bacteroides] merdae, [Bacteroides] forsythus, and CDC group DF-3. This unnamed genus is in the Cytophaga-Flavobacterium-Bacteroides phylum and is most closely related to the genus Porphyromonas. The spiral-shaped strain, strain ASF 457, is in the Flexistipes phylum and exhibits sequence identity with rodent isolates of Robertson. The remaining four ASF strains, which are extremely oxygen-sensitive fusiform bacteria, group phylogenetically with the low-G+C-content gram-positive bacteria (Firmicutes, Bacillus-Clostridium group). ASF 356, ASF 492, and ASF 502 fall into Clostridium cluster XIV of Collins et al. Morphologically, ASF 492 resembles members of this cluster, Roseburia cecicola, and Eubacterium plexicaudatum. The 16S rRNA sequence of ASF 492 is identical to that of E. plexicaudatum. Since the type strain and other viable original isolates of E. plexicaudatum have been lost, strain ASF 492 is a candidate for a neotype strain. Strain ASF 500 branches deeply in the low-G+C-content gram-positive phylogenetic tree but is not closely related to any organisms whose 16S rRNA sequences are currently in the GenBank database. The 16S rRNA sequence information determined in the present study should allow rapid identification of ASF strains and should permit detailed analysis of the interactions of ASF organisms during development of intestinal disease in mice that are coinfected with a variety of pathogenic microorganisms.

A 50-year-old woman who had been on maintenance hemodialysis for 5 years developed severe anemia resistant to treatment with iron supplements and erythropoietin 4 months prior to hospital admission. Her stool occult blood test was positive, and an initial panendoscopy revealed evidence of possible antral gastritis. However, repeated administration of sucralfate, H2 blockers and a proton pump inhibitor was not effective in preventing further gastrointestinal tract blood loss and subsequent refractory anemia. She required multiple blood transfusions and hospital admissions during this period. There was no obvious coagulopathy or thrombocytopenia. After her third admission, a second panendoscopy demonstrated the typical picture of watermelon stomach. A trial of hormone therapy with estrogen and progesterone increased the hemoglobin level within a month without further evidence of active gastrointestinal bleeding. From our experience with this case, we found that the diagnosis of antral vascular ectasia (watermelon stomach) with bleeding requires a high degree of clinical alertness and careful endoscopic examination. Estrogen and progesterone therapy may provide a good option for treating the disease in uremic patients without an obvious complication. To the best of our knowledge, this is the first report demonstrating the use of maintenance hormone therapy in a female uremic patient to successfully treat watermelon gastric bleeding.

We present a patient with thyroid cancer, who developed respiratory acidosis, tachycardia and hyperthermia during isoflurane anesthesia. Malignant hyperthermia was suspected on the basis of clinical manifestation and laboratory finding. With early diagnosis and treatment the patient survived the episode.

The tumor-suppressor gene p53 acts as "the guardian of the genome", sensing DNA damage and initiating protective responses. To examine the hypothesis that p53 abnormality leads to increased genomic alterations in primary tumor cells, our study utilized 51 primary tumors of cervical carcinoma and 10 microsatellite markers. These markers were mapped to the short arms of chromosomes 3 and 5, covering the regions 3p13-25 and 5p15.1-15.3. Genomic deletion on 3p and 5p was correlated with genetic or epigenetic p53 inactivation pathways, including p53 mutation, genetic deletion of p53 and cervical infection with human papillomavirus. The proportion of abnormal p53 was found to be significantly higher in the cases exhibiting loss of heterozygosity (LOH) on 5p (p < 0.001), supporting the hypothesis of the presence of a p53-dependent pathway to cervical tumorigenesis. In contrast, however, LOH on 3p was found to be independent of p53 inactivation. A common deletion region, 3p22-24, was identified in 44% of informative cases, and genomic loss at this specific region was correlated with early tumorigenic onset and poor grade of tumor differentiation. Diversity within the patterns of genomic alteration in the same form of cancer suggests different sets of risk/tumorigenic profiles, molecular pathogenesis, as well as prognosis and outcome.

Pentazocine is a potent ligand at both opioid and sigma receptors, but with opposite stereoselectivities. Whereas (-)-pentazocine has high affinity for a number of opioid receptors, (+)-pentazocine labels sigma 1 receptors. Iodination of (-)-pentazocine at the 3'-position reverses its selectivity for opioid and sigma 1 receptors. 3'-(-)-Iodopentazocine competes at sigma 1 receptor binding sites with a Ki value of 8 nM, compared to approximately 40 nM for (-)-pentazocine. 3'-(-)-Iodopentazocine also has lost its affinity for opioid receptors. In contrast, iodination of (+)-pentazocine lowers its affinity at sigma 1 receptors. Synthesis of [125I]3'-(-)-iodopentazocine is readily performed with incorporations of up to 80%. Binding is of high affinity and shows the selectivity anticipated for a sigma 1 receptor-selective ligand. Exposing membranes prebound with [125I]3'-(-)-iodopentazocine to ultraviolet light can covalently couple the ligand into the membranes. Polyacrylamide gel electrophoresis reveals a major band at about 25 kDa and a minor one at about 20 kDa, indicating photolabeling of sigma 1 receptors with minor incorporation into sigma 2 sites.

Behaviorally, sigma1 agents modulate opioid analgesia. To examine possible mechanisms responsible for these interactions, we have identified a cell line containing both sigma1 and opioid receptors. [3H](+)-pentazocine binding in BE(2)-C human neuroblastoma cells is high affinity (KD 3.4 +/- 0.7 nM) and high density (Bmax 2.98 +/- 0.14 pmol/mg protein). Competition studies reveal a selectivity profile similar to that of sigma1 sites in guinea pig brain. (+)-Pentazocine has no effect upon either basal or forskolin-stimulated cyclase in the BE(2)-C cells, but cAMP accumulation is inhibited by the morphine, DPDPE and naloxone benzoylhydrazone. (+)-Pentazocine at concentrations as high as 10 microM does not affect this opioid effect, implying that sigma1/opioid interactions are not mediated at the level of the cell. This suggest that their behavioral interactions result from interacting neural circuits. Although (+)-pentazocine is without effect in the cyclase system, it does block carbachol-stimulated phosphoinositol turnover (IC50 6.5 +/- 1.14 microM). The specificity of the effect is confirmed by the ability of haloperidol (1 microM) to shift the IC50 value of (+)-pentazocine 2-fold to the right.

(-)-Pentazocine is active in the tailflick assay in CD-1 mice, although it shows a biphasic dose-response curve with a peak effect of only 30%. Co-administration of haloperidol shifts the dose-response curve to the left and elevates the maximal response to 70% through a blockade of sigma 1 receptors, but the curve remains biphasic. (+)-Pentazocine is inactive in all antinociceptive assays, either alone or with haloperidol. The analgesic actions of (-)-pentazocine are readily reversed by nor-binaltorphimine, but not by the mu-selective opioid receptor antagonist beta-funaltrexamine, implying a kappa 1-opioid receptor mechanism of action. This conclusion is supported by the ability of antisense oligodeoxynucleotides directed against the KOR-1 clone, which encodes the kappa 1-opioid receptor, to block (-)-pentazocine analgesia.

Phosphodiester antisense oligodeoxynucleotides (ODNs) directed against various domains of the cloned mouse delta receptor DOR-1 reduce delta-opioid receptor binding in vivo and in vitro. The present study examines the stability of an antisense ODN (275 nM) directed against the delta-opioid receptor and its effect on DOR-1 mRNA in cultured neuroblastoma cells and in vivo. When added to NG108-15 cells, much of the antisense ODN is degraded. However, > 1% is intact, associated with cells, and stable for at least 72 h. Northern blot analysis demonstrates that treatment of NG108-15 cells with the antisense ODN reduces the levels of a species of DOR-1 mRNA by approximately 25%. Similarly, intrathecal administration of the antisense ODN results in the accumulation of intact ODN within the spinal cord, which is stable for at least 72 h, although the levels of accumulation in vivo are lower than in vitro after either 4 or 72 h. Antisense ODN treatment lowers DOR-1 mRNA levels by approximately 25%. The loss of mRNA both in vivo and in vitro corresponds quite well to the decreases in receptor binding previously observed by our laboratory and is consistent with reduction of delta-opioid receptor protein in vitro as determined by western blot with a monoclonal antibody selective for the delta-opioid receptor. In conclusion, these studies indicate that a small, but significant, proportion of ODN is taken up by cells and remains intact for up to 72 h. This appears to be sufficient to down-regulate mRNA levels of delta-opioid receptors and their expression.

Antisense oligodeoxynucleotides (18-20 bases) to a cloned delta opioid receptor (DOR-1) lower delta binding in NG108-15 cells by 40%-50%. Changing 4 bases to generate a mismatch antisense oligodeoxynucleotide or mixing the corresponding sense and antisense oligodeoxynucleotides prior to treatment of the cells eliminates the inhibition of binding, confirming the specificity of the response. In vivo, an antisense oligodeoxynucleotide to DOR-1 given intrathecally lowers delta, but not mu or kappa 1 spinal analgesia. The mismatch antisense oligodeoxynucleotide is inactive. Delta analgesic sensitivity gradually returns by 5 days after the last antisense treatment, indicating the lack of irreversible damage or toxicity. These studies demonstrate that DOR-1 mediates delta analgesia at the level of the spinal cord and confirm at the molecular level traditional pharmacological studies implying distinct receptor mechanisms for delta, mu, and kappa 1 analgesia. The use of antisense approaches may prove valuable in understanding the receptors mediating opioid pharmacology.

Both (+)-pentazocine and (-)-pentazocine antagonize morphine analgesia equally well. This lack of stereospecificity implies an non-opioid mechanism of action. The antagonism of morphine analgesia by (+)-pentazocine is reversed by haloperidol, a potent dopamine D2 and sigma receptor antagonist. The inactivity of the highly selective dopamine D2 receptor antagonist (-)-sulpiride indicates that both (+)-pentazocine and haloperidol are acting through sigma receptors. Haloperidol, but not (-)-sulpiride, also enhances morphine analgesia. Together, these results suggest the presence of a tonically active anti-opioid sigma system within the brain.

An 87-year-old woman who had had a lower abdominal mass for 32 years underwent a laparotomy. Surgery revealed a 21-cm left ovarian dermoid cyst with torsion. Pathologic examination showed a hemorrhagic infarct due to torsion, mucinous cystadenoma and tuberculosis within the tumor. Tuberculosis was also found in the endometrium, both ovaries, oviducts and omentum. The patient's recovery was uneventful after surgery and medical treatment. The clinical manifestations of tuberculosis can vary widely. Tuberculosis of an ovarian dermoid cyst may be silent for a long period of time unless other complications occur.

The purpose of this survey is to find out whether Hakka group has higher incidence of thalassemia traits in our population. A total of 1,115 healthy employees from a company were screened by complete blood count (CBC) with indices. Those subjects with mean corpuscular volume (MCV) less than 80 fl were further evaluated by hemoglobin electrophoresis and modified hemoglobin H (Hb H) inclusion staining to confirm the diagnosis of beta- and alpha-thalassemia traits, respectively. We evaluated and compared the crude occurrence rates of thalassemia traits in Hakka, non-Hakka, and Taiwanese. Subjects with one or both Hakka parents had higher crude incidence of alpha-thalassemia traits than other groups of subjects, but this phenomenon wasn't found in beta-thalassemia traits.

Phlebectasia, defined as abnormal venous dilation, may occur in a number of different sites. Two cases with definite diagnosis of internal jugular phlebectasia were reported. The first case was a 6-year-old girl with a bulging mass on right neck for 3 years. Angiography and CT scan showed definite diagnosis, and the bulging mass was resected from the internal jugular vein (IJV). The second case was a 66-year-old female patient, also complained of a bulging mass on her right neck. Sonogram and CT scan also showed the same diagnosis. Because it did not bother the patient, she was just under close observation. From the three kinds of diagnostic modalities, we found sonography is an effective technique because of its clarity, safety and low cost.

We have reported that many cases of Hb H disease have a complication of iron overload without a history of multiple blood transfusion or prolonged iron therapy. We determined their iron absorption by 59Fe whole body counting in 13 such cases. Also 10 normal subjects were studied as a control group. The results showed a significant increase in iron absorption to 20.3%, in contrast to 6.9% in the normal control. This was further documented by their RBC incorporation (i.e. the percentage of orally administered) 59Fe recovered in the total RBC mass) on day 14 (13.7% vs 6.1%). The degree of ineffective erythropoiesis might not be severe considering their similar 59Fe utilization by RBC (i.e. the percentage of absorbed 59Fe recovered in the RBC) to the normals (86.3% vs. 84.3%).

An elongated styloid process may be a source of craniofacial and cervical pain. The syndrome is characterized by a variety of symptoms including difficulty in swallowing, sore throat, glossodynia, headache and hemifacial pain. Sometimes, the pain is localized or radiates to the jaw and ear and may simulate pain of dental origin. Diagnosis is readily made by radiographic examination and palpating the tonsillar fossa. The only effective treatment is surgical shortening of the styloid process. Three patients, two women and a man, underwent surgery in our department for symptomatic elongation of the styloid process. The surgical procedures were conducted under general anaesthesia via a cervical approach in one patient and intraoral approach in two patients. All patients were completely relieved after styloid process resection and did not have any postoperative complications, except for cervical numbness in one case.

Ninety paturients undergoing elective cesarean section were included in this randomized study to compare the influence of the injected volume of epidural morphine (EM) on postoperative analgesia. Three similar groups of patients (n = 30 each) received 2 mg EM in 2 ml, 10 ml, and 20 ml saline respectively one hour after the last dose of 2% lidocaine. Pain scores (0-10) at rest (including uterine contraction pain) at the 2nd, 4th, 8th, 12th, 18th, and 24th h were compared among the three groups. There were no statistically significant differences of pain score among the three groups although lower pain score was present in the 20 ml group since the 8th h and thereafter. Regarding the number of patients who requested additional meperidine for pain relief 3 in 2 ml group, 2 in 10 ml group and 1 in 20 ml group respectively. The result may suggest that the influence of the injected volume of EM on postcesarean analgesia is not obvious.