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Bacteroides fragilis is an important etiological agent of serious infections in humans. Rapid methods, readily adaptable to use in medical laboratories, are needed to detect antibiotic resistance and decrease the likelihood of therapy failure. The aim of this study was to determine the prevalence of B. fragilis cfiA-positive isolates. The second purpose was to investigate the carbapenemase activity in B. fragilis strains by Carba NP test. In the study, 5.2% of B. fragilis isolates are phenotypically resistant to meropenem. The cfiA gene was identified in 6.1% of B. fragilis isolates. The MICs of meropenem were significantly higher in cfiA-positive strains. The presence of the cfiA gene along with the IS1186 was detected in one B. fragilis strain which was resistant to meropenem (MIC 1.5 mg/L). The Carba NP test results were positive for all the cfiA-positive strains, including those susceptible to carbapenems based on their MIC values. A review of the literature revealed that the rate of B. fragilis with the cfiA gene varies from 7.6 to 38.9% worldwide. Presented results are in line with the other European studies. Phenotypic testing with the Carba NP test, it seems to be a viable alternative for the cfiA gene detection in B. fragilis isolates. The positive result obtained is of greater clinical importance than the detection of the gene cfiA.

Purpose: The aim of this study was to analyze the susceptibility of Bacteroides and Parabacteroides spp. strains, isolated from patients hospitalized in the clinical hospital in Poland to penicillin, amoxicillin with clavulanic acid, imipenem, clindamycin, and metronidazole. Methods: We analyzed susceptibility of 476 isolates to routinely use for the treatment of anaerobic bacterial infections antibiotics. E test method was used to determining the minimal inhibitory concentration values. To show the trend of drug resistance, we compared data from two periods within the years 2003-2017. Results: Research results indicate that the problem of resistance is mainly related to strains belonging to non-fragilis Bacteroides. In the analyzed periods, there was an increase in the percentage of clindamycin-resistant isolates (35.21% vs. 53.33%), amoxicillin/clavulanic acid (2.83% vs. 8.15%), and imipenem (1.41% vs. 3.7%). In isolates belonging to Parabacteroides distasonis, we observed a constant high (∼50%) percentage of clindamycin-resistant strains. The overwhelming majority of B. fragilis strains were resistant to penicillin (>95%) and about 20% of the isolates were not susceptible to clindamycin. Conclusions: Clindamycin, due to the high and increasing percentage of resistant strains, may not be a good choice in the empirical therapy of infections caused by Bacteroides and P. distasonis. Our study highlighted the importance of a routine or at least periodic monitoring of antimicrobial susceptibility of anaerobic Gram-negative bacilli, providing important information for appropriate therapy. The study shows that infection caused (or suspected of being caused) by Bacteroides and Parabacteroides spp. can be empirically treated with metronidazole or imipenem.

Cytosolic and mitochondrial human branched chain aminotransferase (hBCATc and hBCATm, respectively) play an integral role in brain glutamate metabolism. Regional increased levels of hBCATc in the CA1 and CA4 region of Alzheimer's disease (AD) brain together with increased levels of hBCATm in frontal and temporal cortex of AD brains, suggest a role for these proteins in glutamate excitotoxicity. Glutamate toxicity is a key pathogenic feature of several neurological disorders including epilepsy associated dementia, AD, vascular dementia (VaD) and dementia with Lewy bodies (DLB). To further understand if these increases are specific to AD, the expression profiles of hBCATc and hBCATm were examined in other forms of dementia including DLB and VaD. Similar to AD, levels of hBCATm were significantly increased in the frontal and temporal cortex of VaD cases and in frontal cortex of DLB cases compared to controls, however there were no observed differences in hBCATc between groups in these areas. Moreover, multiple forms of hBCATm were observed that were particular to the disease state relative to matched controls. Real-time PCR revealed similar expression of hBCATm mRNA in frontal and temporal cortex for all cohort comparisons, whereas hBCATc mRNA expression was significantly increased in VaD cases compared to controls. Collectively our results suggest that hBCATm protein expression is significantly increased in the brains of DLB and VaD cases, similar to those reported in AD brain. These findings indicate a more global response to altered glutamate metabolism and suggest common metabolic responses that might reflect shared neurodegenerative mechanisms across several forms of dementia. Alzheimer's Research Trust, UK (ARUK); BRACE (Bristol Research into Alzheimer's and Care of the Elderly); Brains for Dementia Research; Medical Research Council This work was supported by Alzheimer's Research Trust, UK (ARUK). The SWDBB, which provided the tissue and clinical data for this study, is supported by BRACE (Bristol Research into Alzheimer's and Care of the Elderly), Brains for Dementia Research and the Medical Research Council. We would like to also acknowledge the valuable academic input from Prof Seth Love, University of Bristol, UK.

The purpose of this study was to assess drug susceptibility of clinical B. fragilis strains and to determine any correlation between drug resistance and the presence of specific genes. Antimicrobial susceptibility was assessed using E-tests. All isolates were analyzed with the PCR technique for the presence of antibiotic resistance genes (cepA, cfxA, cfiA, ermF, ermB, ermG, nim), insertion sequences elements (IS1186, IS1187, IS1188, IS942), and enterotoxin-encoding genes (bft). Susceptibility tests yielded the following rates of resistance to the evaluated antibiotics: penicillin G (100%), clindamycin (22.5%), cefoxitin (6.3%), amoxicillin/clavulanic acid (1.8%). All strain were susceptible to imipenem, and metronidazole. The following antibiotic resistance genes were detected in the evaluated isolates: cepA (in 96.4% of isolates), cfxA (in 12.6%), cfiA (in 1.8%), and ermF (in 25.2%). Genes ermB, ermG, and nim were not found. The presence of the cepA gene showed no correlation with the penicillin G MIC. However, we observed a high correlation between cefoxitin MIC values and the presence of gene cfxA as well as a nearly complete correlation between clindamycin MIC values and the presence of gene ermF. The presence of a bft gene was detected in 14.4% of the analyzed B. fragilis isolates; with the bft-1 allele found in 75%, bft-2 in 25%, and bft-3 in none of the isolates. Antibiotic susceptibility profiles of enterotoxin gene-positive isolates in our study did not differ from those of enterotoxin gene-negative isolates.

the analyzed peritoneal fluid and bile specimens were comparable. Multiple bacterial species were significantly more common in bile isolates than in peritoneal fluid isolates. A total of 61,7% of aerobic Gram-negative bacillus isolates obtained from peritoneal fluid and bile produced ESBL. The proportions of vancomycin-resistant enterococci (VRE) and enterococci exhibiting high-level aminoglycoside resistance (HLAR) were 32,6% and 43,5%, respectively. Ertapenem-resistant K. pneumoniae was detected in 22,2% of peritoneal fluid cultures and 71,4% of biliary cultures. Methicillin resistance was detected in 85,7% of staphylococcal isolates. The proportion of anaerobes detected in peritoneal fluids was relatively high at approximately 17% and included predominantly Gram- negative species. All Gram-negative anaerobes showed resistance to benzylpenicillin. Conclusions: Etiologies and susceptibility pattern of IAls must be monitored on a ward, hospital, regional, and world-wide scale and the findings implemented into epidemiologic surveillance programs and proposed treatment protocols.

Objectives The aims of this study were (i) to analyse strains of the genera Bacteroides and Parabacteroides isolated from clinical specimens for phenotypic resistance to clindamycin, (ii) to detect erm genes in the isolates and (iii) to determine any correlation between in vitro resistance and the presence of erm genes. Methods The Bacteroides and Parabacteroides isolates analysed were obtained from patients hospitalised at teaching hospitals in Poland. Antimicrobial susceptibility testing was performed by Etest and the results were interpreted according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. All isolates were analysed by PCR for the presence of the resistance genes ermF, ermB and ermG. Results Resistance to clindamycin was detected in 31.0% (62/200) of all evaluated isolates, with the ermF and ermB genes detected in 31.0% (62/200) and 0.5% (1/200) of isolates, respectively. No isolates with ermG were detected among the evaluated strains. Pearson’s test showed an almost perfect correlation between clindamycin minimum inhibitory concentrations (MICs) and the presence of ermF in Bacteroides spp. and Parabacteroides distasonis isolates, although the ermF gene was also present in 10 clindamycin-susceptible isolates of Bacteroides spp. Conclusions This study demonstrated a substantial proportion of Bacteroides (22.5–100% depending on the species) and 50.0% of Parabacteroides strains exhibiting resistance to clindamycin. The clindamycin MIC for resistant strains in each case was ≥256 mg/L. Resistance to clindamycin in Bacteroides and Parabacteroides species is correlated mainly with the presence of the ermF gene.

Most Clostridium species are part of saprophytic microflora in humans and animals; however, some are well-known human pathogens. We presented the challenges in identifying the Clostridium species isolated from a patient with an infected open dislocation of the proximal interphalangeal joint of the fourth digit of the right hand. The clinical materials were intraoperative samples collected from a patient diagnosed with an injury-related infection, with soft tissue loss and tendon sheath involvement. The available biochemical, molecular, and genetic techniques were used in identifying the isolated bacteria. The isolated bacterium was shown to have low biochemical activity; hence, it was not definitively identified via biochemical tests Api 20A or Rapid 32A. Vitek 2 and mass spectrometry methods were equally inconclusive. Clostridium tetani infection was strongly suspected based on the bacterium's morphology and the appearance of its colonies on solid media. It was only via the 16S rRNA sequencing method, which is non-routine and unavailable in most clinical laboratories, that this pathogen was excluded. Despite appropriate pre-laboratory procedures, which are critical for obtaining reliable test results, the routine methods of anaerobic bacterium identification are not always useful in diagnostics. Diagnostic difficulties occur in the case of environment-derived bacteria of low or not fully understood biological activity, which are absent from databases of automatic bacterial identification systems.

In the search for new antimicrobial and anticancer agents, a series of (aryl/heteroaryl-piperazino-alkyl)-substituted derivatives of benzo[b]furans were prepared. All compounds were characterized by 1H NMR, 13C NMR, ESI-MS spectra and elemental analyses. Most of the investigated compounds had no antimicrobial activity (MIC > 512 mg/L) except for 2l, 2m and 2o, which showed activity against Candida albicans. None of the tested compounds showed significant anticancer activity in K562 and HeLa cells.

Adequate identification of anaerobic bacteria still presents a challenge for laboratories conducting microbiological diagnostics. The aim of this study was to compare the use of Api 20A and MALDI-TOF MS techniques for identification of obligate anaerobes. The results indicate that MALDI-TOF MS ensures a rapid and accurate identification of the species isolated from patients.

Anaerobic bone and joint infections are uncommon, although the number of anaerobic infections is presumably underestimated because of difficulties with isolation and identification of obligate anaerobes. This study describes two cases of complicated Bacteroides fragilis peri-implant infection of the lumbar spine, infection of the hip and osteomyelitis. Bacteria were identified with the use of a mass spectrometer, VITEK MS system. Drug susceptibility was performed with the use of E-test. The EUCAST breakpoints were used for interpretation with B. fragilis ATCC 25285 as a control. In the two described cases clinical samples were collected for microbiological examination intraoperatively and simultaneously empirical treatment was applied. B. fragilis was isolated in monoculture or in a combination with other bacteria. The treatment was continued according to the susceptibility tests. In a case one clindamycin failure was observed and clindamycin resistance of the isolate was likely due to inadequate time of therapy. Difficulties in collecting an adequate samples and culturing anaerobic bacteria cause that not all infections are properly recognized. In a successful therapy, identification and determination of the susceptibility of the pathogen are essential as well as an appropriate surgical debridement.

Five aminoalkyl 1H-benzo[de]isoquinoline-1,3(2H)-diones were synthesized and evaluated for antimicrobial activity. Microorganisms used in this study included aerobic and facultative anaerobic bacteria Staphylococcus aureus, Escherichia coli and Stenotrophomonas maltophilia, and obligatory anaerobes Bacteroides fragilis, Bacteroides thetaiotaomicron and Propionibacterium acnes. Moreover, Candida albicans yeast was used. The minimum inhibitory concentration (MIC) was determined for the test compounds. Among the tested derivatives, two compounds 1 and 2 have shown the most potent antibacterial as well as antifungal activities.

Establishment of the etiology in blood infection is always advisable. The purpose of this study was to evaluate the proportion of different bacterial species, including aerobic and anaerobic bacteria in blood cultures of patients hospitalized in transplantation wards of a large clinical hospital between 2010 and 2012. A total of 1994 blood samples from patients who were treated at one of two transplantation wards of a large hospital in Warsaw were analyzed using an automated blood culture system, BacT/ALERT (bioMerieux, France). The 306 bacterial strains were obtained from the examined samples. The highest proportion were bacteria from the family Enterobacteriaceae (112 strains; 36.6%) with Escherichia coli (61 strains), Klebsiella pneumoniae (30 strains), and Enterobacter cloacae (10 strains) most commonly isolated. The non-fermenting bacilli constituted 21.6% (66 strains), with most common Stenotrophomonas maltophilia (31 strains), Pseudomonas aeruginosa (14 strains), Achromobacter spp. (12 strains), and Acinetobacter baumannii (3 strains). Most frequent Gram-positive bacteria were staphylococci (25.2%). Of 77 staphylococcal strains, 56 were coagulase-negative staphylococci and 21 Staphylococcus aureus. Other Gram-positive bacteria included enterococci (14 strains) and Streptococcus pneumoniae (1 strain). Obligatory anaerobic bacteria were represented by 19 strains (6.2% of total isolates). Among all Enterobacteriaceae, 49 isolates (43.7%) produced extended-spectrum s-lactamases (ESBLs). Resistance to methicillin was detected in 62% of S aureus isolates and in 46% of coagulase-negative staphylococci. Of 14 enterococci cultured from blood samples, 2 strains (14.3%) were resistant to vancomycin. Both were Enterococcus faecium. Resistant strains of Gram-negative and Gram-positive bacteria are significant problems for patients in the transplantation ward.

Immunocompromised patients and patients undergoing invasive procedures are predisposed to bacterial infections, due to the possibility of micro-organism translocation from their physiological habitat. Infectious complications may occur both in the early and late post-transplantation periods. The purpose of this study was to evaluate the proportion as well as susceptibility profiles of obligatory anaerobes in the etiology of infections in patients hospitalized at transplantation wards of a large clinical hospital in Warsaw. A total of 104 strains of obligatory anaerobes derived from patients hospitalized in two transplantation clinics at a clinical hospital in Warsaw were evaluated. The strains were isolated from 87 clinical samples collected from 84 patients of two transplantation wards between 2007 and 2012. A total of 104 obligatory anaerobic bacterial strains were isolated and identified, with Gram-positive and Gram-negative bacteria constituting 60.6% and 39.4% of the isolates, respectively. Almost exclusively non−spore-forming anaerobes were detected in evaluated samples. The present study showed all isolated Gram-positive bacteria to be susceptible to s-lactam antibiotics. Metronidazole-resistant bacteria were found among the genera Propionibacterium and Actinomyces . All Gram-negative rods were susceptible to imipenem and metronidazole. Among them, Bacteroides spp. and Parabacteroides distasonis showed resistance to penicillin G (100%). Because of their pathogenicity and altered antibiotic susceptibility profiles, the bacteria of the genera Bacteroides and Parabacteroides are of greatest clinical importance. Approximately 25% of isolates exhibit also resistance to clindamycin. Because of the growing rates of clindamycin resistance, the role of metronidazole in the treatment of Bacteroides spp. is of increasing importance.

In the search for novel biological agents, a series of new derivatives N-substituted 1,3-benzoxazol-2(3H)-one, 5-chloro-1,3-benzoxazol-2(3H)-one, 6-bromo-1,3-benzoxazol-2(3H)-one were prepared. All of the compounds were characterized by 1H NMR, 13C NMR and ESI MS spectra. Moreover, for compound 1 an Xray structure was determined. All derivatives were tested for antimicrobial activity against a selection of Gram-positive, Gram-negative bacteria and yeasts. The selected compounds (2-8, 10) were tested for their cytotoxic properties in K562, HeLa and normal cells.

Halogen and aminoalkyl derivatives of methyl 5-methoxy-2-methyl-1-benzofuran-3-carboxylate were prepared using 5-hydroxy-2-methyl-3-benzofuranocarboxylic acid as starting material. (1)H-NMR spectra were obtained for all of the synthesized structures, and for compounds 1 and 2 X-ray crystal structures were obtained too. All derivatives were tested for antimicrobial activity against a selection of Gram-positive cocci, Gram-negative rods and yeasts.

In the search for novel antimicrobial agents, a series of new derivatives - N-substituted imides were prepared. All of the compounds were characterized by 'H NMR and ESI MS spectra. These derivatives were tested for antimicrobial activity. Microorganisms used in this study included aerobic and facultative anaerobic bacteria such as Staphylococcus aureus, Escherichia coli, Stenotrophomonas maltophilia, and obligatory anaerobes such as Bacteroides fragilis, Bacteroides thetaiotaomicron and Propionibacterium acnes. Moreover, Candida albicans yeast was used. For representatives of all species the MICs of the investigated compounds were determined. Most of investigated derivatives had no antimicrobial activity (MIC512 mg/L) except the derivative 22 which showed slight activity against Gram-positive aerobes and anaerobes.

The aim of this study was to estimate the contribution strictly anaerobic bacteria in the etiology of infections in patients on surgery and orthopedic wards.We examined 159 samples taken from patients hospitalized in surgical wards and 179 clinical specimens taken from orthopedic patients. Clinical strains of obligate anaerobes were identified by API 20A biochemical tests (ATB Expression, bioMerieux S.A., France). Susceptibility of the clinical strains was examined by ATB ANA (bioMerieux S.A., France) system. The MIC values were determined by the gradient diffusion method, Etest (AB BIODISK, Sweden i bioMerieux S.A., France).Gram-negative bacteria predominant in the samples taken from surgical patients, Most frequently we isolated rods of the genus Bacteroides (26%): B. fragilis, B. ovatus/B. thetaiotaomicron, and B. distasonis. In 44 samples (28%) we identified only anaerobic bacteria. Multibacterial isolations, with the participation of anaerobic and aerobic flora, dominated among patients in the study. Overall 238 strictly anaerobic bacteria were cultured from patients hospitalized in orthopedic wards. Gram-positive bacteria accounted for 78%. The most frequently were isolated Peptostreptococcus (56%), Propionibacterium (10%) species. In this study all Bacteroides strains were resistant to penicillin G. Some species were resistant to clindamycin, as well. Overall 40% of Bacteroides strains taken from surgical and 50% isolated from orthopedic wards showed no sensitivity to this antibiotic. A similar phenomenon was observed among bacteria of the genus Prevotella.In samples taken from orthopedic patients we observed the predominance of Gram-positive anaerobic bacteria. Some of them were part of the normal flora but they should not be excluded as an etiology agents of infection. The specimens taken from patients treated in surgical wards showed the presence of a mixed microflora, which included aerobic and anaerobic bacteria, primarily Gram-negative rods. Rational empirical therapy of infections with anaerobes should be mainly based on the resistance pattern in each ward and hospital. In view of the increasing in the number of resistant strains is necessary to monitor drug resistance of anaerobic bacteria.

The aim of the study was to assess the prevalence and antibiotic susceptibility profiles of strictly anaerobic Gram-negative bacteria isolated from clinical samples taken from hospitalized patients from 01.01.2007 to 31.12.2008. The specimens were cultured using media, incubated at 37 degrees C under anaerobic conditions. Biochemical identification and antibiotic susceptibility were done in an automated system ATB Expression (bioMerieux S.A, France). For selected strains of Bacteroides sp. sensitivity was determined using E-test (AB BIODISK, Sweden). Overall 1274 strains of obligate anaerobes were isolated. Gram-negative bacteria were cultured in number of 333 strains. Most frequently isolated was Bacteroides sp. (46,9%) and Prevotella sp. (29,7%). Isolated bacteria are still susceptible to imipenem (100%), metronidazole (100%) and beta-lactam antibiotics with beta-lactamase inhibitors: amoxicillin/clavulanate (97,8%) piperacillin/tazobactam (99,1%), ticarcillin/clavulanate (99,1%).

The aim of the study was to assess prevalence and antibiotic susceptibility profiles ofGram-negative strictly anaerobic bacteria isolated from clinical specimens taken from hospitalized patients in 2005-2006. Biochemical identification and antibiotic susceptibility were done in an automated system ATB Expression (bioMerieux sa). From 12262 specimens examined 867 strains of obligate anaerobes were isolated. Gram-negative strictly anaerobic bacteria were cultured in number of 138 strains (15,9%). All cultures were performed on Columbia agar and Schaedler agar media (bioMerieux sa) supplemented with 5% sheep blood and incubated at 37 degrees C for 48-120 h in 85% N2, 10% H2, 5% CO2. Most frequently isolated was Bacteroides spp. (41,3%). For this group beta-lactamase activity was evaluated by using nitrocefin disc test (Cefinase BBL, Becton Dickinson and Co., Cockeysville, MD, USA). Production of ESBLs was detected with the use of two disc diffusion methods: the double-disc synergy test (DDST) according to Jarlier et al. and the diagnostic disc (DD) test according to Appleton. ESBLs were produced by 5,3% strains of Bacteroides spp. For all Bacteroides spp. strains MIC values were determined by gradient diffusion method Etest (AB BIODISK, Sweden). ESBLs and MIC were performed on Wilkins-Chalgren solid medium supplemented with 5% sheep blood (Difco Lab., USA) and all plates were incubated at 35 degrees C for 48 hours in 85% N2, 10% H2, 5% CO2. Most Gram-negative obligate anaerobes isolated from clinical specimens are still susceptible to imipenem (100%), metronidazole (99,3%) and beta-lactam antibiotics with beta-lactamase inhibitors: piperacillin/tazobactam (99,3%), ticarcillin/clavulanate (99.3%), amoxicillin/clavulanate (97.8%).

Background Many strictly anerobic bacteria are a part of the human commensal microflora. Especially multitudinously they inhabit the skin, mucous membranes, gastrointestinal tract, respiratory, and genital tracts. Infections with these bacteria may occur after escape of the bacteria from their natural habitat. There are often mixed anerobic and aerobic infections. After rupture of the gastrointestinal tract or surgery, the organisms can cause significant pathology including abscesses and bacteremia. Objective The aim of this study was to estimate the prevalence of gram-negative strictly anerobic bacteria isolated from different samples collected from patients on transplant wards. Materials and Methods Samples from patients with suspected infections. Underwent isolation and identification of microorganisms under anerobic conditions using standard laboratory methods. Results Gram-negative rods were observed in 46% of clinical samples, most frequently Bacteroides genus as well as Fusobacterium necrophorum/F.nucleatum and F.mortiferum (14%). Most species of the genus Bacteroides were accompanied by Escherichia coli, less frequently with other aerobic gram-negative rods or gram-positive cocci. Conclusion Gram-negative bacteria were frequently isolated in the samples. Because they are the part of the normal flora, this observation indicated the endogenous nature of infections resulting from bacterial translocation out of their natural habitat.