Clostridium innocuum is a vancomycin-resistant pathogen that may cause antibiotic-associated diarrhoea.

OBJECTIVES: Clostridium innocuum can cause extraintestinal infection in patients with underlying diseases. The role of C. innocuum in antibiotic-associated diarrhoea (AAD) remains unknown. METHODS: Clinical information of 103 patients from whom C. innocuum was isolated was reviewed. We carried out cellular and animal experiments to examine the pathogenic potential of C. innocuum in AAD. RESULTS: Eighty-eight per cent (91/103) of the 103 patients received antibiotics within 2 weeks of diarrhoea onset. Patients were further classified into two groups, severe colitis and diarrhoea, according to clinical severity level. The mortality rate was 13.6% (14/103) among the patients from whom C. innocuum was isolated. The lowest concentrations at which 90% of the isolates were inhibited for metronidazole and vancomycin were 0.5 and 16 mg/L, respectively. All isolates tested were susceptible to metronidazole but resistant to vancomycin. Nineteen randomly selected isolates (ten from severe colitis group, nine from diarrhoea group) were subjected to further in vitro cellular examinations. The level of cytotoxicity to Vero cells was significantly higher in isolates from the severe colitis group at both 24 and 48 hours after inoculation (24 and 48 hours, p 0.042 and 0.033, respectively). We observed apoptotic changes that subsequently led to cell death in C. innocuum-infected Vero cells. Tissue damages, necrotic changes and oedema were observed in the mouse ileal loop infected by C. innocuum. CONCLUSIONS: Vancomycin-resistant C. innocuum may play a potential role as a causative agent of AAD. The clinical manifestations of AAD caused by C. innocuum were diarrhoea or severe colitis, including pseudomembranous colitis.

MicroRNA-497 suppress osteosarcoma by targeting MAPK/Erk pathway.

BACKGROUND: The aim of this study was to study the mechanism of miRNA-497 in the apoptosis of osteosarcoma cells. METHODS: MG-63 cells were divided into the three groups: NC, BL and miRNA groups, NC group were treated with nothing; BL group were transfected with blank vector; miRNA group were transfected with miRNA-497. Cell proliferation rate was detected by MTT method; Apoptosis rate was detected by flow cytometry and measuring the gene and protein expression of MAPK, Erk and P 21 by RT-PCR and Western blot. RESULTS: The cell proliferation rate of miRNA group was significantly lower compared to NC group and BL group (p < 0.05); while the apoptosis rate of miRNA group (32.17 ± 3.23 %) was significantly higher than that of NC group  (8.40 ± 1.78 %) and BL group (8.83 ± 0.99 %) (p < 0.05, respectively). Regarding the gene expression detection, we found that gene and protein expressions of MAPK, Erk and P21 of miRNA group were significantly different compared to NC and BL groups (p < 0.05, respectively). CONCLUSION: MiR-497 can activate P21 expression by inhibiting the expression of MAPK/Erk signaling pathway, thus promoting the apoptosis of osteosarcoma cells (Fig. 5, Ref. 18).

Clostridium innocuum is a significant vancomycin-resistant pathogen for extraintestinal clostridial infection.

OBJECTIVES: Extra-intestinal clostridial infection (EICI) is rare but can be fatal. Traditional phenotypic methods can only assign many of the Clostridium species to the genus level. METHODS: A total of 376 non-repetitive Clostridium isolates from sterile sites were collected and subjected to matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) Biotyper analysis and 16S rRNA sequencing. Antimicrobial susceptibility was determined, and clinical characteristics of the patients were assessed. Clostridium innocuum isolates were characterized by genome sequencing and genotyping. We used molecular and cellular methods to explore the virulence and resistance mechanisms of C.innocuum. RESULTS: Clostridium innocuum was the second most common species to cause EICI, only next to Clostridium perfringens. All Clostridium isolates showed susceptibility to clindamycin, metronidazole, penicillin, piperacillin and ampicillin-sulbatam, while C. innocuum isolates were invariably resistant to vancomycin. Among 24 patients with EICI caused by C. innocuum, two (8.3%) had diarrhoea, three (12.5%) had soft-tissue infection, six (25%) had appendicitis and four (16.7%) each had shock and gastrointestinal perforation. The 30-day mortality was 16.7%. The C. innocuum isolated from different sites could not be separated from one another by genotyping. No known toxin genes were identified in the genome of C. innocuum but the species expressed cytotoxicity to epithelial cells. d-Alanine-d-alanine ligase, alanine racemase and d-alanyl-d-alanine carboxypeptidase are three main genes responsible for vancomycin resistance in C. innocuum. CONCLUSIONS: Vancomycin-resistant C. innocuum is a previously unrecognized, yet prominent, cause for EICI. Genome analysis showed that the species could carry a lipopolysaccharide-like structure that is associated with cytotoxicity to cells in vitro.

Overexpression of a glycine-rich protein gene in Lablab purpureus improves abiotic stress tolerance.

Glycine-rich protein (GRP) is involved in the response to abiotic and biotic stresses in plants. A novel GRP gene in Lablab purpureus has been identified. The cDNA of LpGRP was obtained from an SSH library constructed with root tissues of L. purpureus MEIDOU 2012 by waterholding for 10 days. The function of LpGRP was also evaluated in Arabidopsis. The cDNA of LpGRP has 555 bp and encodes a 184-amino acid protein. LpGRP was induced by drought and improved tolerance to abiotic stress. In LpGRP overexpressing Arabidopsis, the tolerance of transgenic seedlings to drought and salt was improved, and transgenic seeds showed insensitivity to both ABA and NaCl. The insensitivity to ABA indicated that there was crosstalk between LpGRP and ABA-responsive genes. These results indicated that LpGRP is a drought-responsive gene that can increase the drought and salt tolerance of Arabidopsis seedlings overexpressing LpGRP.

The association between the RAGE G82S polymorphism, sRAGE and chronic periodontitis in Taiwanese individuals with and without diabetes.

BACKGROUND AND OBJECTIVE: The present study investigated the association between the RAGE G82S polymorphism, the plasma levels of sRAGE and chronic periodontitis in subjects with and without diabetes mellitus (DM). MATERIAL AND METHODS: A total of 230 patients with DM and 264 non-DM participants were recruited for this study. Genotyping of the RAGE G82S polymorphism was accomplished using polymerase chain reaction-restriction fragment length polymorphism, and associations were analyzed with the chi-squared test and logistic regression analysis. RESULTS: In the non-DM group, the chi-squared test showed that the frequency distributions of the G82S polymorphism were significantly different between chronic periodontitis and non-chronic periodontitis subjects (χ(2) = 8.39, p = 0.02). A multivariate logistic regression model showed that the (G82S + S82S) genotypes were associated with a significantly increased risk of chronic periodontitis development compared to the G82G genotype (adjusted odds ratio = 2.06, 95% confidence interval: 1.08-4.07). In the DM group, there was no association between the G82S polymorphism and chronic periodontitis development when a multivariate logistic regression was performed. Plasma levels of sRAGE were significantly higher in subjects with the G82G genotype compared to those with the (G82S + S82S) genotypes in both the non-DM (856.6 ± 332.0 vs. 720.4 ± 311.4 pg/mL, p = 0.003) and DM groups (915.3 ± 497.1 vs. 603.5 ± 298.3 pg/mL, p < 0.0001). However, there was no difference in plasma sRAGE levels between chronic periodontitis and non-chronic periodontitis subjects in both the DM and non-DM groups. Moreover, when the subjects were further sub-divided by the G82S polymorphism, the difference in plasma levels of sRAGE between chronic periodontitis and non-chronic periodontitis subjects in the DM and non-DM groups remained statistically insignificant. CONCLUSIONS: The present study revealed that the RAGE G82S polymorphism was associated with chronic periodontitis in the non-DM group but not in the DM group. Our results also showed that the plasma levels of sRAGE were significantly higher in subjects with the RAGE G82G genotype, and this correlation was not affected by the presence of chronic periodontitis in the DM and non-DM groups.

Mapping an aphid resistance gene in soybean [Glycine max (L.) Merr.] P746.

Soybean aphid (SA: Aphis glycines Matsumura) is one of the most serious pests of soybean [Glycine max (L.) Merr.] worldwide. A single dominant gene was found to control SA resistance in soybean line P746, which exhibits antibiosis resistance. This study aimed to define the location of the SA resistance gene in P746. A F2:3 mapping population, including 312 individuals, was created based on the cross of P746 and 'Dongnong 47'. Combined with bulked segregant analysis, all of the 1015 simple sequence repeats (SSR) from the soybean consensus map were used to locate the tentative genomic region of the SA resistance gene in P746. The effort resulted in the mapping of R_P746, the SA resistance gene in P746, and was flanked on either side by Satt334 and Satt335 on chromosome 13. By chromosome walking with SSRs from BARCSOYSSR_1.0, R_P746 was mapped between BARCSOYSSR_13_1278 and BARCSOYSSR_13_1363, with distances of 4.2 and 2.6 cM, respectively. The results indicate that R_P746 might be different to the SA resistance genes previously reported. The markers that are closely linked to R_P746 are expected to be useful for marker assisted selection in future soybean aphid resistance breeding programs.

A pregnant mouse model for the vertical transmission of Brucella melitensis.

Abortion is the major clinical sign of brucellosis in animals but little is known about the underlying mechanisms. This study was designed to evaluate a pregnant mouse model for the vertical transmission of Brucella melitensis using four infectious doses: 10(3) colony-forming units (CFU), 10(4) CFU, 10(5) CFU, and 10(6) CFU. During the experimental period, no instances of abortion were recorded, but stillbirths were observed in the groups infected with doses of 10(4) CFU and higher. Regardless of whether the fetuses were stillborn or alive, transmission of bacteria to the fetus and bacterial replication in the cytoplasm of placental trophoblast giant cells were detected. A higher degree of bacterial colonization was found in the placenta than in the spleen or fetus. Doses of 10(5) CFU of B. melitensis or higher produced a severe, necrotizing placentitis similar to the pathological damage observed in ruminants. The data suggest that experimental murine brucellosis resembles ruminant brucellosis and represents a potential model for studying the pathogenic mechanisms of B. melitensis.

HLA-A*31:01 and different types of carbamazepine-induced severe cutaneous adverse reactions: an international study and meta-analysis.

HLA-A*31:01 was reported to be associated with carbamazepine (CBZ)-induced severe cutaneous adverse reactions (SCAR), including drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). We conducted an international study using consensus diagnosis criteria to enroll a total of 93 patients with CBZ-SCAR from Europe or Asia. We found that HLA-A*31:01 showed a significant association with CBZ-DRESS in Europeans (P<0.001; odds ratio (OR) (95% confidence interval (CI))=57.6 (11.0-340)), and the strong association was also found in Chinese (P<0.001; OR (95% CI)=23.0 (4.2-125)). However, HLA-A*31:01 had no association with CBZ-SJS/TEN in neither Chinese nor Europeans. By comparison, HLA-B*15:02 showed a strong association with CBZ-SJS/TEN in Chinese (P<0.001, OR (95% CI)=58.1 (17.6-192)). A meta-analysis of this and other published studies confirmed that in all populations, HLA-A*31:01 had an extremely strong association with CBZ-DRESS (P<0.001, a pooled OR (95% CI)=13.2 (8.4-20.8)), but a much weaker association with CBZ-SJS/TEN (P=0.01, OR (95% CI)=3.94 (1.4-11.5)). Our data revealed that HLA-A*31:01 is a specific predictor for CBZ-DRESS but not for CBZ-SJS/TEN. More studies are needed to investigate the genetic determinant of CBZ-SJS/TEN in Europeans. Considering the potential clinical utility, the cost-effectiveness of the combined HLA-A*31:01 and HLA-B*15:02 genetic test to prevent CBZ-SCAR in Chinese needs further investigation.

Identification of a hidden outbreak due to the spread of a VIM-3-producing, extensive drug-resistant Pseudomonas aeruginosa (XDRPA) clone at a regional hospital in Taiwan.

A review of the annual prevalence of Pseudomonas aeruginosa at a regional hospital in Taiwan revealed a significant increase in the incidence of extensive drug-resistant P. aeruginosa (XDRPA) from 2∙1% in 2003 to 5∙8% in 2007. The first XDRPA isolate was recovered in 2001 from the emergency ward. The widespread dissemination of XDRPA isolates to more than 10 other wards was discovered the following year. Six pulsotypes of 67 XDRPA isolates from 2006 onwards were identified and 91% were a single strain, suggesting the existence of a hidden outbreak. Prior to the recognition of the outbreak, the majority of cases were not considered to be healthcare-associated infections until molecular evidence was provided. A cohort measure was launched by the infection control practitioners that effectively controlled the outbreak. Patients with XDRPA were mostly referred from neighbouring long-term care facilities, which may have been the reservoir of the XDRPA clone.

Development of carbapenem resistance during therapy for non-typhoid Salmonella infection.

Multidrug-resistant Salmonella infection is a global problem, and carbapenems may represent the last therapeutic choice. We report a case of infection caused by ceftriaxone-resistant and ciprofloxacin-resistant Salmonella enterica serotype Typhimurium. A bla(CMY-2) -containing Tn6092, located on a self-transferable IncI1 plasmid, was found in all isolates derived from the patient. During ertapenem treatment, the strain developed carbapenem resistance. Apart from the OmpD deficiency found in all isolates, the strain further developed OmpC deficiency through a single gene mutation, and became carbapenem-resistant. Salmonella appears to be very plastic in developing antimicrobial resistance. Care must be taken by physicians when treating multidrug-resistant Salmonella infection.

Effects of different contacting pressure on the transfer function between finger photoplethysmographic and radial blood pressure waveforms.

BACKGROUND: The blood pressure (BP) waveform is suggested to reflect the whole-body blood supply distribution, but its non-invasive assessment is not sufficiently user friendly for practical applications. The present authors studied the correlation between BP and photoplethysmography (PPG) waveforms, with the aim of determining the optimal range for contact pressure stimulation (PS) to produce a reliable transfer function in their harmonic parameters. METHODS: Finger PPG and radial-artery BP signals were measured simultaneously and noninvasively on healthy volunteers (n = 45). PS of 0-200 mmHg was applied to the finger, and 1 min data sequences were recorded. In frequency-domain analysis, linear regression was applied to the calculated amplitude ratios or the first five harmonics between BP and PPG waveforms. RESULTS: In the 60 mmHg-PS group, the BP-PPG regression of amplitude ratios was highest, and the agreements between them were also the best verified by Bland-Altman analysis. CONCLUSION: In the present study, frequency-domain analysis was performed to study the correlation between BP and PPG waveforms. Differences in pressure-induced-vasodilation responses underlie the different BP-PPG waveform correlations obtained by applying different PSs. The non-invasively derived PPG parameters might help to provide an easier method to acquire the radial-artery BP waveform, and hence broaden the application of BP waveform analysis.

Emergence of carbapenem-resistant Escherichia coli in Taiwan: resistance due to combined CMY-2 production and porin deficiency.

Eight pairs of Escherichia coli isolates with various carbapenem susceptibilities from 8 patients were prospectively collected to study the development of resistance. All carbapenem-resistant E. coli isolates were resistant to all tested ss-lactams antibiotics except tigecycline. Identical pulsed-field gel electrophoresis (PFGE) patterns were found in carbapenem-susceptible and -resistant isolates but different PFGE patterns occurred among patients. A CMY-2 ss-lactamase was found in all E. coli isolates. No previously reported carbapenemase genes were detected. Examination of outer membrane protein (OMP) profiles revealed that OmpA was not found in all isolates, while OmpC and OmpF were lost in carbapenem-resistant isolates. Loss of both OmpC and OmpF represents the major mechanism of the development of carbapenem resistance in those patients with CMY-2-producing E. coli infections.

Long-term outcome and short-term survival of patients with systemic lupus erythematosus after bacteraemia episodes: 6-yr follow-up.

OBJECTIVE: To describe the nature of bacteraemia in SLE patients and determine the short-term survival and long-term outcome of these patients. METHODS: Analysis of the medical records of 1442 SLE patients who were regularly followed up in a tertiary teaching medical centre from 2000 to 2005. RESULTS: Among 1442 SLE patients, 240 patients (17%) developed at least one episode of bacteraemia, corresponding to an incidence of 92.7 cases/1000 hospital admissions. Since SLE diagnosis, the overall survival of our patients was 92% at 5 yrs, 86% at 10 yrs and 79% at 15 yrs. However, after one episode of bacteraemia, the survival decreased to 76% at 30 days and 67% at 360 days. Of the 336 episodes of bacteraemia, 167 were community-acquired (49.7%) and 169 were nosocomial (50.3%). Staphylococcus aureus was the leading cause of Gram-positive bacteraemia. Among Gram-negative bacteria, non-typhoidal Salmonella and Escherichia coli were the most common species. Community-acquired Salmonella and Streptococcus bacteraemia were more common than nosocomial infections. Klebsiella and Acinetobacter spp. were significantly more responsible for nosocomial than community-acquired bacteraemia. Patients infected with Acinetobacter, Klebsiella or Pseudomonas had lower probabilities of 14-day survival (71.4, 55.6, 42.9%, respectively). CONCLUSIONS: Among SLE patients, an episode of bacteraemia was associated with an unfavourable long-term outcome. The bacterial species significantly influenced short-term survival. Therefore, when empiric antibiotic therapy is initiated in SLE patients who are suspected of bacteraemia, we suggest use of antibiotics that are effective against Pseudomonas, Klebsiella, Acinetobacter, S. aureus, and E. coli.

The levels of volatile sulfur compounds in mouth air from patients with chronic periodontitis.

BACKGROUND AND OBJECTIVE: Volatile sulfur compounds may be the main source of oral malodor. The aim of this study was to clarify the relationship between periodontal parameters and volatile sulfur compounds and to evaluate the improvement of several halitosis-related outcomes by tongue scraping, nonsurgical periodontal treatment (including oral hygiene instruction) and oral hygiene instruction/chlorhexidine + cetyl pyridinium gargling. MATERIAL AND METHODS: Seventy-two chronic periodontitis patients with heavy tongue coating were assessed for oral malodor and periodontal status. Oral malodor was evaluated by measuring the levels of volatile sulfur compounds using OralChroma and the organoleptic test score. Thirty participants were selected for the subsequent experiments: tongue scraping; nonsurgical periodontal treatment; and oral hygiene instruction/chlorhexidine + cetyl pyridinium gargling. Twenty-five participants completed all experimental stages. RESULTS: Significant correlations were observed between the organoleptic test score and hydrogen sulfide (H2S), methyl mercapton (CH3SH), tongue coating score and volatile sulfur compounds, which was also significantly correlated with bleeding on probing percentage and tongue coating score. Tongue scraping significantly reduced the levels of volatile sulfur compounds. Further reduction of volatile sulfur compounds after nonsurgical periodontal treatment and oral hygiene instruction/chlorhexidine + cetyl pyridinium gargling were noted compared with baseline. CONCLUSION: Volatile sulfur compounds, with H2S and CH3SH as the main components, in mouth air are the prominent elements of malodor. Volatile sulfur compounds were decreased by more than 50% after tongue scraping. Nonsurgical periodontal treatment and oral hygiene instruction/chlorhexidine + cetyl pyridinium gargling maintained a significantly lower level of malodor compared with baseline.

Correlations of androgen deficiency with clinical symptoms in Taiwanese males.

The purpose of this study was to elucidate correlations between different biochemical measurements of androgen deficiency and clinical symptoms in male residents of Taiwan. An investigation of the serum biochemical markers for androgen deficiency in 650 males, including total testosterone, calculated free testosterone, and bioavailable testosterone, was conducted. Measurements of clinical symptoms were obtained using a questionnaire of the androgen deficiency in the aging male (ADAM) by St Louis University (SLQ). Correlations among the biochemical markers, correlations of the biochemical markers and age, and relationships between the biochemical markers and the SLQ were evaluated. The sensitivity and specificity of the SLQ were determined. Bioavailable and calculated free testosterone correlated better with age than did total testosterone. Eighty percent of the men had a positive SLQ, and 20% had a negative SLQ. The percentage of positive SLQ results increased with age. No statistically significant difference was noted between the biochemical markers of bioavailable and calculated free testosterone levels and the SLQ status except for men aged over 70 years. The SLQ in this study showed an acceptable sensitivity of about 80%, but the specificity was poor (about 20%). In conclusion, bioavailable testosterone and calculated free testosterone were more-closely correlated with age and may be better biochemical markers for androgen deficiency. SLQ might not be a suitable single measurement for androgen deficiency and should be used together with biochemical markers.

Genotyping analysis of colonizing candidal isolates from very-low-birthweight infants in a neonatal intensive care unit.

To analyse the relatedness of colonizing candidal isolates from very-low-birthweight infants hospitalized in a neonatal intensive care unit (NICU), we prospectively collected 86 candidal isolates from 20 infants, including 67 isolates of Candida albicans from 15 infants, 17 isolates of Candida parapsilosis from five infants and two isolates of Candida glabrata from one infant, who also had C. albicans colonization, over a one-year period. All 86 isolates were genotyped by infrequent-restriction-site polymerase chain reaction (IRS-PCR) and electrophoretic karyotyping (EK) with pulsed-field gel electrophoresis. A total of 15 genotypes were identified by IRS-PCR and 12 genotypes by EK. Some infants shared a common genotype. From a single infant, an identical genotype was found in 11 of 13 cases where at least two isolates of same Candida species were available for genotyping analysis, regardless of anatomical site, how many isolates were recovered or how many times. Should an infant harbour a candidal strain, they may harbour this strain at multiple sites and for a prolonged period.

Isolation of Salmonella enterica serotype choleraesuis resistant to ceftriaxone and ciprofloxacin.

Salmonella enterica serotype choleraesuis (S choleraesuis) usually causes systemic infections in man that need antimicrobial treatment. We isolated a strain of S choleraesuis that was resistant to ceftriaxone and ciprofloxacin from a patient with sepsis. Ciprofloxacin resistance was associated with mutations in gyrA and parC, whereas the ampC gene (bla(CMY-2)), responsible for ceftriaxone resistance, was carried by a transposon-like mobile element. This element was found inserted into finQ of a potentially transmissible 140 kb plasmid, with an 8 bp direct repeat flanking the junction regions. The appearance of this resistant S choleraesuis is a serious threat to public health, and thus constant surveillance is warranted.

Invasive pneumococcal infections: a clinical and microbiological analysis of 53 patients in Taiwan.

OBJECTIVE: To track penicillin susceptibility among Streptococcus pneumoniae causing invasive diseases and to evaluate risk factors for antibiotic resistance. METHODS: A retrospective study was performed in a medical center of all patients with invasive pneumococcal infections based on positive microbiological findings, confirmed by appropriate clinical and laboratory findings. MICs of penicillin and ceftriaxone were determined and interpreted by NCCLS methodology. RESULTS: Fifty-three episodes of invasive S. pneumoniae infections (ISPI) among 22 children and 31 adults were identified. The disease patterns of ISPI were similar between children and adults, and the most common modes were pneumonia (70%) and primary bacteremia (23%). The rate of penicillin-nonsusceptible S. pneumoniae (PNSP) isolated from pediatric patients was higher than that in adult patients (95.5% vs. 54.8%, P < 0.001). This finding was correlated to prior antibiotic use that was more common in children (36.4%) than in adults (18.9%). The rate of penicillin-resistance among S. pneumoniae isolates (PRSP) was extremely high in this area: 45.5% from pediatric patients and 41.9% from adult patients. More adults (90.3%) with ISPI had major underlying diseases than children (4.5%). This may explain why adult patients tended to run an unfavorable outcome (mortality rate, 51.6% and 4.5% in adults and children, respectively), although most of the cases with empyema were children. None of the patients enrolled in this study received pneumococcal vaccination. CONCLUSION: We suggest that vaccines be administered for young children and the elderly with major underlying diseases to prevent ISPI.

Molecular epidemiology of nalidixic acid-resistant campylobacter isolates from humans and poultry by pulsed-field gel electrophoresis and flagellin gene analysis.

To investigate the potential of poultry products as the source of human infections associated with quinolone-resistant campylobacters, 140 human and 75 poultry isolates of nalidixic acid-resistant campylobacters were collected between 1996 and 1998, and analysed by two molecular typing methods. By the analysis of restriction fragment length polymorphism of the flagellin gene, 33 distinct patterns were obtained, with 18 of which shared by both human (89%) and poultry (93%) isolates. By the pulsed-field gel electrophoresis of SmaI-restricted macrofragments, 105 different profiles were obtained, and 11 were found in both human (40%) and poultry (23%) isolates. When the two typing methods were combined, 112 unique genotypes were obtained, 11 of which were shared by both populations, including 53 (38%) human isolates and 14 (19%) poultry isolates. Although domestic poultry products are still important sources of the quinolone-resistant campylobacter infections in humans, there are other factors that might contribute to these increasing infections simultaneously. A more stringent policy in the use of antimicrobial agents in food animals can no longer be ignored.

Molecular epidemiology of nosocomial infection associated with multi-resistant Acinetobacter baumannii by infrequent-restriction-site PCR.

Acinetobacter baumannii was considered endemic in a university-affiliated tertiary hospital. A significant increase was noted in the proportion of nosocomial infections associated with this micro-organism from 1996 to 1999, although no apparent clusters could be found. Between July 1998 and February 2000, 58 nosocomial isolates of A. baumannii were collected and characterized by antibiotyping and a genotyping method, infrequent-restriction-site PCR (IRS-PCR). High resistance to the 14 antimicrobial agents examined was observed among the isolates. Of the 13 antibiograms detected, eight were multi-resistant to gentamicin and almost all of the traditional and extended-spectrum beta-lactams. These multi-resistant strains consisted of 41 isolates (71%), distributed amongst different wards and intensive care units (ICUs). By IRS-PCR, 23 types were obtained, with one major type found among 28 (48%) isolates. All of these 28 isolates were collected from surgical ICUs. It appears that a single strain of multi-resistant A. baumannii was responsible for the prevalence of nosocomial infection amongst surgical patients, clearly differentiating this outbreak from the previous endemic situation. An efficient molecular typing method played a vital role in making this discrimination.