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PubMed1992

Synergism of trimethoprim and ciprofloxacin in vitro against clinical bacterial isolates.

For the first time, the effects of combinations of trimethoprim and a fluoroquinolone (ciprofloxacin) against gram-positive and gram-negative bacterial isolates were evaluated in vitro. Synergism was found in 31% (fractional inhibitory concentration, FIC) and 33% (fractional bactericidal concentration, FBC) of 121 clinical isolates of various bacterial strains, most often in Escherichia coli, staphylococci, and enterococci. Antagonism occurred in 1% (FIC) and 3% (FBC). The combination of trimethoprim and ciprofloxacin merits further evaluation for potential usefulness as a clinical regimen.

Ciprofloxacin↗
PubMed1975

In vitro antibacterial activity of amikacin, a new aminoglycoside, against clinical bacterial isolates from children.

Four hundred and fifty-eight clinical bacterial isolates from a children's hospital were examined for antibiotic susceptibility to amikacin (BB-KS) in comparison with a number of other antibiotics by the disk diffusion and agar dilution methods. The wide spectrum of activity of amikacin against Gram-negative bacteria was confirmed; it included E. coli, Proteus species, Enterobacter species, and Pseudomonas aeruginosa. Staphylococci were highly sensitive, but other Gram-positive bacteria tested were resistant. A disk zone diameter of 10 mm effectively separated resistant form sensitive bacteria in a standard disk diffusion test.

Amikacin↗
PubMed2026

Draft genome sequences of 14 bacterial isolates from the rhizosphere of bioenergy sorghum.

We report the draft genome sequences of a collection of 14 bacterial isolates obtained from the rhizosphere soil of bioenergy sorghum (Sorghum bicolor [L.] Moench). These isolates represent the genera Acidovorax, Nocardioides, Agrobacterium, Peribacillus, Caulobacter, Pseudomonas, Rhizobium, Sphingomonas, Priestia, Dyadobacter, Roseomonas, and Bacillus.

bacterial isolates↗
PubMed1990

[Susceptibilities of clinical bacterial isolates to antimicrobial agents. A study mainly focused on imipenem. Reported by the Research Group for Testing Imipenem Susceptibility on Clinical Isolates].

This study was conducted to investigate susceptibilities of clinical bacterial isolates to imipenem (IPM) and other antibacterial agents at 64 hospital laboratories throughout Japan from September to December of 1988. In this study, identification and susceptibility testing were carried out at each laboratory and the tests were performed according to the disk dilution method recommended by NCCLS in which susceptibilities are classified into "S", "MS", "I" and "R". IPM showed markedly high in vitro activities against Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus agalactiae, Enterococcus faecalis, Haemophilus influenzae, Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae, Serratia marcescens, Salmonella spp., Citrobacter freundii, Proteus mirabilis, Proteus vulgaris, Morganella morganii, Providencia rettgeri, Providencia stuartii, Acinetobacter calcoaceticus, Moraxella (Branhamella) catarrhalis, Alcaligenes spp., Peptococcus spp./Peptostreptococcus spp., Bacteroides fragilis and Bacteroides spp. IPM also had strong activities against Achromobacter xylosoxidans and Pseudomonas aeruginosa, but less active against Flavobacterium spp., E. faecium, coagulase-negative staphylococci (CNS), Staphylococcus aureus and Pseudomonas cepacia. In a study in which activities of IPM against bacteria isolated from different clinical sources were compared, differences in susceptibilities were observed among S. aureus, CNS, A. calcoaceticus and P. aeruginosa, but such differences were not apparent among S. pneumoniae, E. faecalis, H. influenzae, E. coli, K. pneumoniae, E. cloacae, C. freundii, S. marcescens or P. mirabilis.

Bacteria↗
PubMed2004

Haloalkane and haloacid dehalogenases from aerobic bacterial isolates indigenous to contaminated sites in Africa demonstrate diverse substrate specificities.

Five bacteria were isolated from contaminated sites in Nigeria and South Africa using the culture enrichment technique. They were subjected to standard cultural, biochemical and microbiological techniques and identified to be species of Bacillus, Burkholderia, Corynebacterium, Micrococcus and Pseudomonas. Axenic cultures of the bacterial isolates utilized 1,2-dichloroethane (1,2-DCE) as the sole carbon source up to a final substrate concentration of 10 mM. Their mean generation time in 1,2-DCE ranged significantly (P<0.05) from 9.77 to 15.72 h with the maximum chloride release ranging between 59% and 86%. All the bacterial isolates produced two different dehalogenases, viz. one which is heat labile and specific for halogenated alkanes with optimum activity at a pH of 7.5 and the other which is more heat stable with a higher pH optimum of 9.0 and specific for halogenated alkanoic acids. However, the two enzyme types when tested demonstrated wide substrate specificities. It is therefore adjudged that these organisms may play a vital role in the bioremediation of sites polluted with chlorinated hydrocarbons.

Bacteria, Aerobic↗
PubMed1996

Three subtypes of the tet(M) gene identified in bacterial isolates from periodontal pockets.

The tet(M) genes were characterized from 84 isolates of 10 different bacterial species isolated from the periodontal pockets of 16 patients with periodontal disease. A 740 bp polymerase chain reaction product from the hypervariable region of the tet(M) structural gene was cleaved with the restriction enzymes AluI and HinfI. Three different restriction patterns were identified for each of the two enzymes. By DNA sequencing, using a direct solid-phase automated sequencing method, the isolates could be grouped into 3 different clusters of tet(M) subtypes. The internal DNA homology within each subtype was 98-100%; the homology between clusters was 89-94%. Two different subtypes were identified in 9 of 10 bacterial species, and the remaining species had 3 different subtypes. One of the subtypes (M3) was seen mainly in the anaerobic isolates. This subtype was different from all earlier sequenced structural tet(M) genes present in the Genbank. Most patients had two different subtypes of tet(M), and a third subtype was seen in the 3 patients who exhibited the greatest variety of tetracycline-resistant bacterial species. It appears that the presence of one subtype of the tet(M) gene within a patient or bacterial species does not prevent the acquisition of another subtype of the same gene. This study identified a new subtype of the tet(M) gene and grouped it into 3 distinct yet highly homologous genetic subtypes.

Bacterial Proteins↗
PubMed2002

Nutrient substrates used by bacterial isolates from the poultry processing environment.

In order to successfully prevent pathogens found in biofilms in poultry processing facilities from contaminating products, knowledge of the sources and properties of the bacteria from these environments is needed. Bacteria were isolated from fresh cut-up meat samples (breast with or without skin, wings, and thighs) that were not stored or were stored at 4 or 13 C (temperatures relevant to poultry processing facilities). Profiles of the nutrient substrates used by individual bacterial species were determined using Biolog microtiter plates with different substrates in 95 wells of each plate. Pure cultures of bacterial isolates were inoculated onto gram-positive (GP) or gram-negative (GN) Biolog plates, and transformation of specific substrates was determined by reduction (indicated by a purple color) of the tetrazolium violet included in each well. Of the 62 substrates common to GP and GN microtiter plates, one-third were used by 50% or more of all bacterial isolates. Similarly, approximately one-third of the substrates were used by gram-negative bacteria but not by gram-positive bacteria. One-fourth of the substrates were also only used by a single isolate in the respective gram-type category. For the remaining 33 substrates on each of the GP and GN plates, a higher percentage of substrates on GN than on GP plates were used by the respective isolates. These substrate utilization profiles of bacteria isolated from the poultry processing environment are a useful reference for selecting nutrients for the growth or control of these bacteria, especially pathogens.

Animals↗
PubMed2006

Characterization of bacterial isolates from industrial wastewater according to probable modes of hexadecane uptake.

Bacterial isolates from industrial wastewater were characterized according to probable modes of hexadecane uptake based on data for cell surface hydrophobicity, emulsifying activity, glycoside content and surface tension of cell-free culture medium. The results obtained suggested that both modes of biosurfactant-enhanced hexadecane uptake by bacterial strains take place, direct uptake and alkane transfer. The increase in cell surface hydrophobicity and glycoside production by the strains suggested the existence of biosurfactant-enhanced interfacial uptake of the alkane. Such mechanism is probably predominant for three isolates, Staphylococcus sp. HW-2, Streptococcus sp. HW-9 and Bacillus sp. HW-4. Secreted biosurfactants enhanced mainly alkane emulsification for most hydrophobic isolate Arthrobacter sp. HW-8, and micellar transfer for most hydrophilic isolate Streptococcus sp. HW-5. For other strains (67%) both mechanisms of biosurfactant-enhanced hexadecane uptake probably take place in similar degree, interfacial uptake and alkane emulsification. The results obtained could contribute to clarifying the natural relationships between the members of water ecosystem studied as well as will reveal potential producers of surface active compounds.

Alkanes↗
PubMed2004

Severe pneumococcal meningitis heralding a deep hypogammaglobulinaemia related to common variable immunodeficiency, at the age of 27 years.

Common variable immunodeficiency with an associated broad immunoglobulin (0.7%) deficit affecting all subclasses, was revealed in a 27-y-old previously healthy female, upon development of a severe pneumococcal meningitis. We report the third case of purulent meningitis complicating this primary immunodeficiency, and the second due to Streptococcus pneumoniae. Clinicians should maintain an elevated suspicion for congenital immunodeficiency, especially when observing adult patients with a negligible prior history.

Adult↗
PubMed2025

Emergence of extensively and pan-drug resistance in clinical bacterial isolates: A systematic scoping review from Ethiopian public health perspective.

INTRODUCTION: The growing challenge of antimicrobial resistance in Ethiopia and itsprogression towards XDR and PDR has become a critical public health concern. Therefore, thisreview determined the current state of emerging XDR and PDR bacteria, including pre-XDR and XDR-TB, their contributing factors, advancements, and future perspectives against drug-resistant bacteria, as well as their implications for public health and insights for future research. METHODOLOGY: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. A systematic search of all available literature was conducted using PubMed/Medline, Scopus, EMBASE, Google Scholar, Hinari, Web of Science, ScienceDirect, Cochrane Library, and African Journals Online databases.This study included original articles published in English that reported XDR and PDR bacteria, Pre-XDR-TB, and XDR-TBb without limit on the study period and publication year. Descriptive statistics were used to summarize the findings. RESULTS: Twenty-five studies published between 2010 and 2025 were included in this review. Among 5620 bacterial isolates identified,1289 were XDR (22.9%), with the prevalence ranging from 5.7% to 43.2%. A total of 440 bacterial isolates were PDR (9.1%), with its prevalence in individual studies ranged from 0.8% to 19.1%. The most common XDR bacteria identified were Klebsiella species; 26.7% (2.8%-84.6%), followed by E. coli; 26.4%(14.6%-35.7%), Acinetobacter species; 24.9%(10.1%-58.3%), and P. aeruginosa; 18.7% (2.8%-44.4%). The most frequently identified PDR bacteria were Acinetobacter species; 17.3% (7.9%-50.0%), followed by Klebsiella species; 13.7%(2.7%-25.8%), E. coli; 10.2%(2.4%-22.6%), and P. aeruginosa; 5.7%(4.3%-33.3%). Additionally, from 1419 MDR-TB and 160 TB confirmed cases, Pre-XDR-TB was 3.4% (2.4%-5.7%) and XDR-TB was 1.5%(0.6%-10.0%). These isolates were identified from different clinical specimens, which represents a significant concern in community and hospital settings. CONCLUSION: The emergence of XDR and PDR represents a major threat to Ethiopian public health, resulting in increased morbidity, mortality, prolonged hospitalizations, high healthcare costs, and challenged treatment options. Urgent national surveillance and genomic detection of resistance mechanisms are needed to better track the spread of drug-resistant bacteria, promote antimicrobial stewardship, and enhance drug and vaccine trials.

Ethiopia↗
PubMed1985

Identification and antibiotic susceptibility of bacterial isolates from burned patients.

We retrieved bacterial blood isolates from 397 adult burned patients admitted over a 7-year period. Sixty-two patients (15.6 per cent) developed true-positive bacterial blood cultures (judged non-contaminants), and of these 30 (48.4 per cent) expired. Pseudomonas aeruginosa (24 isolates), Staphylococcus aureus (19) and Klebsiella pneumoniae (19) were the most frequent isolates. In vitro susceptibilities of 149 isolates were determined to 12 antibiotics (gentamicin, amikacin, ticarcillin, piperacillin, mezlocillin, azlocillin, cefazolin, cefotaxime, ceftazidime, cefoperazone, thienamycin and ticarcillin-clavulinic acid) using agar diffusion assay. Thienamycin proved the most active agent (97 per cent of isolates susceptible). Cefoperazone was the most active cephalosporin (95 per cent susceptible). Twenty-eight organisms demonstrated multiple drug resistance; patients with such organisms had a 71 per cent mortality. Thienamycin was the most active agent against such isolates (27/28 susceptible). Susceptibilities of all 149 isolates to combinations of antibiotics were calculated, assuming no synergism or antagonism; some combinations of third-generation cephalosporins with the newer penicillins may prove to be as effective as combinations including aminoglycosides.

Adolescent↗
PubMed2003

Neonatal sepsis in hospital-born babies: bacterial isolates and antibiotic susceptibility patterns.

OBJECTIVE: To determine the frequency of bacterial isolates from neonatal blood cultures and their susceptibility patterns in hospital-born babies having sepsis. DESIGN: An observational study. PLACE AND DURATION OF STUDY: Obstetrics Unit and Special Care Baby Unit of Khyber Teaching Hospital, Peshawar from 1st January to 31st December 2001. SUBJECTS AND METHODS: This study was carried out on the neonates born and admitted in hospital with positive blood culture reports. Early onset neonatal sepsis (EONNS) and late onset neonatal sepsis (LONNS) were defined as illness appearing from birth to seven days and from eight to twenty-eight days postnatal age respectively. The blood culture reports were analyzed by SPSS package and cross tabulation was done. RESULTS: One hundred and twelve hospital-born babies presented with sepsis. Sixty-seven neonates had positive cultures. Escherichia coli (E. coli) was the commonest organism causing EONNS (35; 77.1%) followed by Pseudomonas (4; 8.9%), Klebsiella (4; 8.9%) and Staphylococcus aureus (2; 4.4%) respectively. In the LONNS E. coli (19; 77.3%) was the commonest followed by Staphylococcus and Pseudomonas (2; 9% each) and Klebsiella (1; 4.5%). The gram-negative organisms showed high degree of resistance to commonly used antibiotics, ampicillin (79.3%), amoxicillin (74.6%) and ceftazidime (71.6%), cefotaxime (55.2%) and comparatively low resistance to gentamicin (43.2%), tobramycin (34.3%), imipinem (23.6%), amikacin (22.3%), ofloxacin and ciprofloxacin (11.9%) respectively. Staphylococcus aureus showed almost the same resistance to ampicillin, 75%, and comparatively low resistance to the rest of the antibiotics as compared to the gram-negative organisms. CONCLUSION: Neonatal sepsis is mainly caused by gram-negative organisms, which are developing resistance to commonly used antibiotics.

Anti-Bacterial Agents↗
PubMed1989

In vitro activity of cefoperazone-sulbactam combinations against cefoperazone-resistant clinical bacterial isolates.

From July 1987 to January 1988, 452 cefoperazone-resistant bacterial isolates were identified among strains subjected to routine susceptibility testing in a clinical microbiology laboratory. The 452 isolates were tested for susceptibility to cefoperazone, sulbactam, and a 2:1 combination of these drugs by agar dilution techniques. The greatest benefit of the cefoperazone-sulbactam combination was noted against Bacteroides spp. and Acinetobacter spp. The combination demonstrated clinically significant synergism against approximately 20% of strains of Pseudomonas aeruginosa.

Acinetobacter↗
PubMed1989

Uptake and incorporation of thymidine by bacterial isolates from an upwelling environment.

Thymidine uptake and incorporation by marine bacterial isolates from an upwelling environment were studied. Of 17 isolates each from upwelled and downwelled water, 1 and 6 isolates, respectively, were found to be negative for [H]thymidine incorporation at a substrate concentration of 19 muM. Strains lacking the ability to take up thymidine were not confined to one genus. The measurable rates of uptake and incorporation by the 34 isolates varied greatly. Studies carried out using starved Vibrio, Pseudomonas, and Cytophaga cells showed that these isolates transported and incorporated thymidine after periods of as long as 5 weeks of nutrient deprivation. This occurred in the absence of any other exogenously supplied nutrients. Overall, these results indicate that not all marine bacteria take up thymidine and that those that do incorporate the nucleoside may do so at very different rates. The assumption that only actively growing or dividing cells incorporate thymidine must be viewed with caution.

Journal Article↗
PubMed2001

Comparison of antimicrobial use and resistance of bacterial isolates in a haematology ward and an intensive care unit.

The objective of the study presented here was to compare antimicrobial use and resistance of bacterial isolates in the haematology ward and the intensive care unit of Bolzano General Hospital. The bacterial organisms isolated most frequently from patients in the two wards (coagulase-negative staphylococci, Enterococcus spp., and Pseudomonas aeruginosa) were investigated for antimicrobial resistance. Isolates obtained from patients in the haematology ward were more often resistant to antimicrobial agents than isolates obtained from patients in the intensive care unit, and the agents against which the highest rates of resistance were found were third- and fourth-generation cephalosporins, carbapenems and monobactams, quinolones, aminoglycosides, and trimethoprim-sulfamethoxazole. These classes of antimicrobial agents were also used more frequently in the haematology ward than in the intensive care unit. Conversely, penicillinic beta-lactam antibiotics, rifamycins, macrolides and lincosamides were used less frequently in the haematology ward than in the intensive care unit, and the rates of resistance against these classes of antimicrobial agents were significantly lower in the haematology ward than in the intensive care unit. The results support the hypothesis that a causal relationship exists between antimicrobial use and the development of resistance and indicate that careful monitoring of antimicrobial use in hospitals is required to identify situations in which prescription patterns are contributing to the development of resistance.

Anti-Bacterial Agents↗
PubMed2005

Feline cholecystitis and acute neutrophilic cholangitis: clinical findings, bacterial isolates and response to treatment in six cases.

Clinicopathological findings from six cats with confirmed cholecystitis or acute neutrophilic cholangitis are presented. Historical findings included lethargy and anorexia or inappetence of up to five days duration. On physical examination all cats were pyrexic and four out of six were jaundiced and had cranial abdominal pain. Bile samples were obtained by cholecystocentesis at exploratory coeliotomy (two cases) or by percutaneous, ultrasound-guided cholecystocentesis (four cases). Gall bladder rupture and bile peritonitis occurred subsequent to ultrasound-guided cholecystocentesis in one case. The most common bacterial isolate was Escherichia coli (four cases); E coli was isolated alone in two cases, in combination with a Streptococcus species (one case) and in combination with a Clostridium species (one case). Streptococcus species alone was isolated from one case, as was Salmonella enterica serovar Typhimurium. The latter is the first reported case of Salmonella-associated cholecystitis in a cat. Concurrent pancreatic or intestinal disease was detected histologically in three cases. All cases were treated with antimicrobials based on in vitro susceptibility results. Treatment was successful in five cases. One cat with concurrent diffuse epitheliotropic intestinal lymphoma was euthanased. Percutaneous ultrasound-guided cholecystocentesis is an effective, minimally-invasive technique enabling identification of bacterial isolates in cats with inflammatory hepatobiliary disease.

Acute Disease↗
PubMed2006

[Efficiency of preventive chemotherapy in children and adolescents from the bacterial isolation foci of tuberculous infection].

A follow-up of 558 children and adolescents contacting the patients with tuberculosis who isolated bacteria was analyzed. In 46.5% of cases, the children and adolescents contacting the patients with tuberculosis were in the foci of drug-resistant Mycobacterium tuberculosis (MBT) in the source of infection. The patients from these foci fell ill with tuberculosis 3.4 times more frequently than those from the foci where the sources of infection isolated MBT susceptible to antituberculous drugs. Processes with bacterial isolation were detected in 47.7% of the ill children and adolescents, primary MBT resistance to antituberculous drugs being noted in 68.8% of cases. Preventive chemotherapy reduces the risk for children and adolescents contacting the patients with tuberculosis to fall ill by 7.6 times. Ineffective preventive chemotherapy performed in those contacting the patients was due to the use of MBT-resistant antituberculous drugs in the source of infection. The administration of the MBT-resistant drugs in the source of infection led to the same high incidence of tuberculosis in children and adolescents from the bacterial foci of tuberculous infection as in its absence.

Adolescent↗