Number Of Bacterial Isolates Research Articles

Preputial microflora of llamas (Lama glama) and alpacas (Vicugna pacos)

Abstract To characterize the normal preputial microflora of healthy male New World camelids (NWC), samples were swabbed from the preputial mucosa of 23 intact and 7 castrated males including 17 llamas and 13 alpacas ranging from 1 day to 16 years of age. The swabs were streaked onto tryptose blood agar with 5% bovine blood, MacConkey's agar, Karmali Campylobacter selective agar and Saboraud's dextrose agar and cultured under aerobic, micro-aerophilic and/or anaerobic conditions. Bacteria but not fungi or Campylobacter were isolated from all 30 animals. The mean numbers of bacterial isolates obtained per male were 3.4 for alpacas (range 2–6), 4.0 for llamas (range 1–7) and 3.7 for both species combined. Of 22 bacterial genera identified from a total of 112 isolates, five were aerobes, 11 were facultative anaerobes and six were obligate anaerobes. Nine isolates failed to subculture and could not be identified. The most frequently isolated genera in descending order of frequency were Staphylococcus, Bacillus, Streptococcus, Bacteroides, Corynebacterium, Arcanobacterium and Actinomyces. This is the first description of the microflora present on the preputial mucosa of healthy llamas and alpacas. Most of the bacteria isolated from the prepuce are considered commensal organisms, but several could be opportunistic pathogens under appropriate conditions.

Assessing techniques for disinfecting sites for inserting intravenous catheters into the jugular veins of horses

The sites of insertion of catheters into the jugular veins of six horses were investigated to determine common isolates and to assess the effectiveness of two disinfection protocols with the hair coat left long, clipped or shaved. Skin commensals (Staphylococcus, Streptococcus and Micrococcus species) and environmental contaminants (Bacillus, Enterobacteriaceae, Aspergillus and Mucor species) were the microorganisms most frequently isolated. Chlorhexidine gluconate and povidone-iodine-based skin disinfection protocols resulted in significant reductions in the number of bacterial isolates from clipped sites. With chlorhexidine, there were no significant differences between the reductions observed at sites with the hair coat left long, clipped or shaved.

Activity profiles of fourteen selected medicinal plants from Rural Venda communities in South Africa against fifteen clinical bacterial species

Fourteen plants used in traditional medicine in the Venda region of South Africa were screened for activity against fifteen bacterial species. Methanol, acetone and hexane extracts and in some cases essential oils were tested using the disc diffusion and the microdilution methods. Most of the extracts were active against at least one bacterial species. Methanol and acetone extracts were the most active while Gram positive bacteria were the most sensitive as compared to Gram negative bacteria. This study has revealed the strong in vitro activity of Syzigium cordatum, Peltophorum africanum, Rhoicissus tridentata, Bridelia micrantha and Ximenia caffra against Gram positive and Gram negative bacteria. Essential oils of Lippia javanica was also effective against most of the bacterial species studied. However, Pouzolzia mixta and Mucuna coriaceae showed less activity. Some plants were more active than commercial antibiotics. This study is the first to test the activity of the selected plants from the Venda region against such number of bacterial isolates and justifies their use by local traditional healers. The identification of the active components of the plants and the determination of the effect of these plants on the immune system will give more information on their activity. Finally, these results may be of importance in identifying candidate plants and essential oils for eventual drug design and other therapeutic purposes, respectively.

Bacterial causes of upper & lower respiratory tract infection in Sheep

This study was designed to investigate the bacterial species that induceupper and lower respiratory tract infection in sheep, and to find out anyrelationship which may exist between them.Therefore two groups of sheep were employed. The first group wassuffering from certain respiratory signs. While the second group was apparentlyhealthy. Each group included 50 sheep. Research samples were collected for aperiod of six months from AL-Shulla Abattoir.Microbiological investigation indicated the isolation of certainmicroorganisms from all animals in both groups from nasal cavity, and from 34lungs of the first group and 16 lungs of the second group. The number of isolatesfrom the nasal cavity, were 200 from different species ,43 isolates from thebronchioles and 70 from the lungs tissue. On the other hand the number ofbacterial isolates from the nasal cavity, bronchioles and the lung tissue of thefirst group were 113, 29 and 55 respectively.The study revealed the isolation of potentially pathogenic bacteria from thelower respiratory system of both groups, these bacteria were namely Pasteurellahaemolytica of serotype (A2), Niesseria spp. and Corynebacterium pyogenes,the number of isolates were 6 for each, and 8 isolates of Staphylococcus aureus.These bacteria were also isolated from the nasal cavity. The isolation of thesebacteria from the nasal strongly suggested their presence in the lungs and theprobable role in lesion formation.Animal inoculation were performed to study the virulence of P.haemolytica which caused certain hemorrhagic lesion in the lung , liver andkidney, with areas of necrosis in the lungs of the experimentally inoculatedrabbit, and caused death in mice. While the inoculation of C. ovis caused thedeath of rabbits within 72 hours, together with the presence of multipleabscessation on the internal organs and abdomenal wall.Sensitivity tests indicated a high sensitivity of most isolates to Gentamicin,Erythromycin and Kanamycin.

Activity profiles of fourteen selected medicinal plants from Rural Venda communities in South Africa against fifteen clinical bacterial species

Fourteen plants used in traditional medicine in the Venda region of South Africa were screened for activity against fifteen bacterial species. Methanol, acetone and hexane extracts and in some cases essential oils were tested using the disc diffusion and the microdilution methods. Most of the extracts were active against at least one bacterial species. Methanol and acetone extracts were the most active while Gram positive bacteria were the most sensitive as compared to Gram negative bacteria. This study has revealed the strong in vitro activity of Syzigium cordatum, Peltophorum africanum, Rhoicissus tridentata, Bridelia micrantha and Ximenia caffra against Gram positive and Gram negative bacteria. Essential oils of Lippia javanica was also effective against most of the bacterial species studied. However, Pouzolzia mixta and Mucuna coriaceae showed less activity. Some plants were more active than commercial antibiotics. This study is the first to test the activity of the selected plants from the Venda region against such number of bacterial isolates and justifies their use by local traditional healers. The identification of the active components of the plants and the determination of the effect of these plants on the immune system will give more information on their activity. Finally, these results may be of importance in identifying candidate plants and essential oils for eventual drug design and other therapeutic purposes, respectively.

Screening of bacteria for the suppression of Botrytis cinerea and Rhizoctonia solani on lettuce (Lactuca sativa) using leaf disc bioassays

Summary Two leaf disc bioassays were developed for screening bacteria as putative biological control agents of Botrytis cinerea and Rhizoctonia solani on lettuce. Aerobic spore and non-spore forming bacteria were isolated from the phylloplane, rhizoplane and rhizosphere of symptom-free lettuce plants grown in the presence and absence of chitin or composted bark soil amendments. Bacteria, previously isolated from other plants, were also included in the primary screen initially against B. cinerea. One hundred and twenty-seven of 700 isolates reduced botrytis rotting of lettuce leaves by more than 50% in the primary screen. Following a secondary screen against B. cinerea, the lead 50 isolates were also tested for suppression of R. solani infection. Four isolates significantly reduced both botrytis and rhizoctonia leaf rotting. Eleven and five isolates gave control of botrytis and rhizoctonia, respectively, equal to that given by the standard fungicides Rovral WP (iprodione) and Basilex (tolclofos methyl). The two most effective isolates against B. cinerea and R. solani were both identified as Bacillus subtilis. Use of soil amendments did not increase the proportion of efficacious isolates recovered. Effective isolates were originally recovered from roots of oilseed rape and lettuce leaves. In general, it was found that bacteria which controlled one disease effectively did not control the second disease nearly as well. The bioassay protocols developed in this study were used successfully in screening a large number of bacterial isolates in a short time.

The effects of amoxicillin therapy on skin flora in infants.

In order to determine the effect of amoxicillin therapy on the perineal skin microbial flora in infants, we took quantitative bacterial and fungal cultures of perineal and sternal areas from 25 infants treated with amoxicillin (40 mg/kg/day) for 10 days. Specimens were obtained prior to therapy, within 3 days of conclusion of therapy, and 14-16 days later. Immediately following therapy, a decline in the number of bacterial isolates occurred on both the perineum (89 to 47) and sternum (84 to 39). The greatest decline occurred in the number of anaerobic bacteria (mostly Peptostreptococcus spp. and Propionibacterium acnes). Other organisms that were less often isolated were aerobic streptococci and Staphylococcus epidermidis. The number of Candida albicans isolates increased from 3 to 11 (p < 0.05) on the perineum, and 1 to 7 (p < 0.025) on the sternum. Four of the infants developed diaper dermatitis. The density of C. albicans increased more than 14-fold following amoxicillin therapy. Cultures done 14-16 days after cessation of therapy revealed an increase in the number of bacterial isolates on the perineum (47 to 72) and on the sternum (39 to 61) and a decline in recovery of C. albicans. This study demonstrates the effects of amoxicillin on the ecology of skin microbial flora in infants-a decrease in the number of bacterial isolates and an increase in recovery of C. albicans.

Pharmaceutical use and antibiotic therapy in intensive care units

The present study has involved a sample of 750 medical or medical/surgical intensive care units. The aim was to identify the variations of antibiotic (AB) use, measured in monetary terms, and to sort out explicative variables accounting for the corresponding expense. Activity and expense data have been recorded for 1997. "Second intention" antibiotics have been defined as follows: imipenem, ceftazidime, cefpirome, cefepime, piperacillin/tazobactam, amikacin, isepamicin, vancomycin and teicoplanin. Only 60 evaluable sheets have been sent back. They include data about 28,000 admissions and 183,960 hospital days. The results are presented as means +/- standard deviation (SD) and the variability has been considered to be important if the ratio SD/mean was > 1. Nosocomial infections (NI) surveillance, antibiotic advisory board and restriction of use for some molecules were present in 95%, 67% and 78% of units, respectively. The units usually had 10 beds (range: 6-24) and the mean activity was 468 +/- 184 admissions/year and 3,066 +/- 1,454 hospital days/year. Mean duration of hospitalisation (MDH) was 6.9 +/- 2.7 days and mean omega score 114 +/- 61. Mean age of patients was 56.5 years, IGS II score 35.7 +/- 7; 29 +/- 16% of patients were mechanically ventilated for more than 48 hours and mortality rate was 17 +/- 7%. The mean number of bacterial isolates per unit was 369 +/- 323: Staphylococcus sp. 30% [including 25% of meticillin-resistant Staphylococcus aureus (MRSA)]; enterobacteria 30% (including 14% of cefotaxime-resistant isolates); Pseudomonas sp. 14% (including 40% of ticarcillin R isolates); other 26%. Pharmaceutical expense was 834 +/- 364 FF per day of hospitalisation, including 536 +/- 273 FF for drugs. Antibiotics accounted for 32% of the expense and second intention molecules for nearly 50% of antibiotic expense. More than 80% of antibiotic expense was accounted for by only 10 molecules. The mean cost/hospital day for the most expensive antibiotic, whatever the molecule ranking first, was 27 FF, for the second and third ones 18 and 14 FF. The expense for the tenth molecule was only 3 FF. There was a correlation between antibiotic expense and number of beds, number of hospital days, MDH, omega score, number of patients mechanically ventilated for more than 48 hours, mortality, number of bacterial isolates and incidence of NI. Molecules thought to be active against MRSA and ticarcillin-resistant Pseudomonas sp. accounted for 7 and 20% of total antibiotic expense, as compared to 7.5 and 4.6%, respectively, of bacterial isolates. As a conclusion, in this sample of 60 intensive care units, differences were shown for the cost of antibiotics, but the variability was low, without major discrepancies. Ten molecules accounted for 83% of total antibiotic expense. The financial impact of molecules against ticarcillin-resistant Pseudomonas sp is high.

Microbiology and biodegradation of resin acids in pulp mill effluents: a minireview.

Resin acids, a group of diterpenoid carboxylic acids present mainly in softwood species, are present in many pulp mill effluents and toxic to fish in recipient waters. They are considered to be readily biodegradable. However, their removal across biological treatment systems has been shown to vary. Recent studies indicate that natural resin acids and transformation products may accumulate in sediments and pose acute and chronic toxicity to fish. Several resin acid biotransformation compounds have also been shown to bioaccumulate and to be more resistant to biodegradation than the original material. Until recently, the microbiology of resin-acid degradation has received only scant attention. Although wood-inhabiting fungi have been shown to decrease the level of resin present in wood, there is no conclusive evidence that fungi can completely degrade these compounds. In contrast, a number of bacterial isolates have recently been described which are able to utilize dehydroabietic or isopimaric acids as their sole carbon source. There appears to be an unusually high degree of substrate specificity with respect of the utilization of abietane congeners and the presence of substituents. Pimaranes do not appear to be attacked to the same extent as the abietanes. This paper reviews the occurrence, chemistry, toxicity, and biodegradation of resin acids in relation to the biological treatment of pulp and paper mill effluents.

Detection of Bacteremia with the BACTEC 16B Resin Blood Culture Medium

A new blood culture medium (16B) containing adsorbent and cationic exchange resins has become available for use with the BACTEC instrument (Johnston Laboratories, Towson, MD). Its purpose is to enhance the detection of bacteremia through binding of antimicrobials. The performance of the BACTEC 16B resin medium was compared with the routine BACTEC 6B medium in patients with suspected sepsis receiving antibiotics. A total of 1,227 blood specimens were inoculated in 6B and 16B media and yielded 93 positive cultures from 43 clinically septic patients. Of 103 bacterial isolates recovered, 63 (61.2%) were recovered in both media, 14 (13.6%) in the routine 6B medium only, and 26 (25.2%) in the resin medium only (P greater than 0.05). Staphylococci, both coagulase positive and negative, were recovered much more frequently in resin medium (P less than 0.01). When the results of all the blood culture sets collected for each patient on any given day were considered, the routine 6B medium was the only source of isolation for seven bacterial species in six patients, and the resin medium was the only source of isolation for nine species in nine patients. However, of the nine organisms whose sole isolation source was the resin medium, eight were recovered early in the course of antibiotic therapy (6 within 24 to 36 hours and 2 within 36 to 48 hours of the first antibiotic dose) and had been isolated previously in routine 6B medium. In no instance was the antibiotic regimen changed as a result of the persistence of the organism in resin medium in the early phases of treatment. The use of resin medium did not improve overall detection time for 63 isolates recovered in both media. In conclusion, although the 16B resin medium did recover a greater number of bacterial isolates, it contributed very little information that might be of use in modifying and improving the treatment of septic patients receiving antimicrobials.

Activity of marine psychrophilic bacteria at elevated hydrostatic pressures and low temperatures

Uptake and metabolic turnover of a variety of radioactively labeled substrates by a number of bacterial isolates from several depths in offshore Atlantic waters were studied in laboratory experiments. The variable conditions were hydrostatic pressure (1 to 400 atm), temperature (1.50 to 15.0°C), concentration of substrate (2 to 500 μg/ml), and time of incubation (4 h to 8 weeks). Elevated hydrostatic pressure and low temperature retarded the rate of metabolism (biosynthesis more than respiration) in all isolates tested, but considerably less in those of psychrophilic character.