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1.
Epidemiol Infect ; 143(14): 2989-92, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25697759

ABSTRACT

Sixty percent of all meat consumed in the UK is imported from European countries where there have been increasing reports of methicillin-resistant Staphylococcus aureus (MRSA) identified in food-producing animals, but rarely from such animals in the UK. Thirty samples each of raw chicken, pork and beef, sourced in England, were collected from retail outlets in Greater Manchester. MRSA was recovered from three chicken samples and one each of pork and beef, all from prepackaged supermarket meat. Four isolates were identified as representatives of the most common human healthcare-associated MRSA clone in the UK [EMRSA-15, spa type t032, belonging to multilocus sequence type clonal complex 22 (MLST-CC22)], suggesting contamination from human source(s) during meat processing. The fifth isolate (from chicken) was multiply-resistant (including oxacillin, ciprofloxacin, erythromycin, clindamycin and tetracycline), identified as ST9-SCCmecIV, spa type t1939 and lacked the immune evasion cluster, a characteristic of livestock-associated strains. This lineage has been identified previously from animals and meat products in Asia and mainland Europe but not the UK.


Subject(s)
Genotype , Meat/microbiology , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Multilocus Sequence Typing , Animals , Cattle , Chickens , Drug Resistance, Multiple, Bacterial , England , Methicillin-Resistant Staphylococcus aureus/classification , Methicillin-Resistant Staphylococcus aureus/genetics , Sheep , Staphylococcal Protein A/genetics
2.
J Appl Microbiol ; 115(5): 1107-16, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23869960

ABSTRACT

AIMS: Environmental contamination plays an important role in the transmission of infections, especially healthcare-associated infections. Disinfection transiently reduces contamination, but surfaces can rapidly become re-contaminated. Antimicrobial surfaces may partially overcome that limitation. The antimicrobial activity of novel surface coatings containing silver and silica prepared using a flame-assisted chemical vapour deposition method on both glass and ceramic tiles was investigated. METHODS AND RESULTS: Antimicrobial activity against a variety of bacteria including recent clinical isolates was investigated based on the BS ISO 22196:2007 Plastics--Measurement of antibacterial activity on plastics surfaces, British Standards Institute, London, method. Activity on natural contamination in an in use test in a toilet facility was also determined. Activity on standard test strains gave a log10 reduction of five after 1-4 h. The hospital isolates were more resistant, but MRSA was reduced by a log10 reduction factor of >5 after 24 h. Activity was maintained after simulated ageing and washing cycles. Contamination in situ was reduced by >99.9% after 4 months. Activity was inhibited by protein, but, although this could be overcome by increasing the amount of silver in the films, this reduced the hardness of the coating. CONCLUSIONS: The coatings had a good activity against standard test strains. Clinical isolates were killed more slowly but were still sensitive. The optimum composition for use therefore needs to be a balance between activity and durability. SIGNIFICANCE AND IMPACT OF THE STUDY: The coatings may have applications in health care by maintaining a background antimicrobial activity between standard cleaning and disinfection regimes. They may also have applications in other areas where reduction in microbial contamination is important, for example, in the food industry.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Disinfection/methods , Silicon Dioxide/pharmacology , Silver/pharmacology , Anti-Bacterial Agents/chemistry , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Plastics , Silicon Dioxide/chemistry , Silver/chemistry
3.
J Appl Microbiol ; 113(4): 964-73, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22747830

ABSTRACT

AIMS: A number of previous studies have shown that plant extracts can inhibit formation of dental plaque. The ability of extracts of Rosmarinus officianalis L., Salvia officianalis L., unfermented cocoa, red grape seed and green tea to inhibit plaque bacteria, glucosyltransferase activity, glucan and plaque formation in an in vitro model using bovine teeth was examined. METHODS AND RESULTS: The antimicrobial activity of the plant extracts against oral bacteria was determined using a standard susceptibility agar dilution technique. Inhibition of growth and acid production from glucose and sucrose by Streptococcus mutans in liquid culture was investigated. Prevention of plaque formation on bovine teeth initiated by Strep. mutans was studied using an artificial mouth. The plant extracts inhibited the growth of oral bacteria and prevented acid production by Strep. mutans. Extracts inhibited glucosyltransferase activity and glucan production and inhibited adhesion to glass. Extracts of R. officianalis L. and S. officianalis L. at 0·25 mg ml(-1) reduced plaque growth by >80%. Green tea extract completely inhibited plaque formation but resulted in a greenish discolouration of the teeth which could not be removed by scrubbing. CONCLUSIONS: The plant extracts, particularly those from R. officianalis L. and S. officianalis L., inhibited glucosyltranferase activity, glucan production and plaque formation in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: The results suggest that the extracts of R. officianalis L. and S. officianalis L. may be useful as antiplaque agents in foods and dental preparations. Bovine teeth can be used as an alternative to hydroxyapatite for studies of plaque formation, but they need to be carefully sterilized before use.


Subject(s)
Dental Plaque/prevention & control , Plant Extracts/pharmacology , Streptococcus mutans/drug effects , Animals , Bacterial Adhesion , Cattle , Dental Plaque/microbiology , Glucans/antagonists & inhibitors , Glucosyltransferases/antagonists & inhibitors , Microbial Sensitivity Tests , Streptococcus mutans/growth & development , Sucrose , Tooth/microbiology
4.
J Anim Sci ; 89(5): 1484-95, 2011 May.
Article in English | MEDLINE | ID: mdl-21239659

ABSTRACT

Relative effects of Beef Quality Assurance (BQA)-related defects in market beef and dairy cows and bulls on selling price at auction was evaluated during 2008. The presence and severity of 23 BQA-related traits were determined during sales in Idaho, California, and Utah. Overall, 18,949 unique lots consisting of 23,479 animals were assessed during 125 dairy sales and 79 beef sales. Mean sale price ± SD (per 45.5 kg) for market beef cows, beef bulls, dairy cows, and dairy bulls was $45.15 ± 9.42, $56.30 ± 9.21, $42.23 ± 12.26, and $55.10 ± 9.07, respectively. When combined, all recorded traits explained 36% of the variation in selling price in beef cows, 35% in beef bulls, 61% in dairy cows, and 56% in dairy bulls. Premiums and discounts were determined in comparison with a "par" or "base" animal. Compared with a base BCS 5 beef cow (on a 9-point beef scale), BCS 1 to 4 cows were discounted (P < 0.0001), whereas premiums (P < 0.05) were estimated for BCS 6 to 8. Compared with a base BCS 3.0 dairy cow (on a 5-point dairy scale), more body condition resulted in a premium (P ≤ 0.001), whereas a less-than-desirable BCS of 2.0 or 2.5 was discounted (P < 0.0001). Emaciated or near-emaciated cows (beef BCS 1 or 2; dairy BCS 1.0 or 1.5) were discounted (P < 0.0001). Compared with base cows weighing 545 to 635 kg, lighter BW beef cows were discounted (P < 0.0001), whereas heavier beef cows received (P < 0.05) a premium. Compared with a base dairy cow weighing 636 to 727 kg, lighter BW cows were discounted (P < 0.0001), whereas heavier cows (727 to 909 kg) received a premium (P < 0.01). Beef and dairy cows with any evidence of lameness were discounted (P < 0.0001). Presence of ocular neoplasia in the precancerous stage discounted (P = 0.05) beef cows and discounted (P < 0.01) dairy cows, whereas at the cancerous stage, it discounted (P < 0.0001) all cows. Hide color influenced (P < 0.0001) selling price in beef cattle but had no effect (P = 0.17) in dairy cows. Animals that were visibly sick were discounted (P < 0.0001). Results suggest that improving BCS and BW, which producers can do at the farm or ranch level, positively affects sale price. Furthermore, animals that are visibly sick or have a defect associated with a possible antibiotic risk will be discounted. Ultimately, animals with minor quality defects should be sold in a timely manner before the defect advances and the discount increases.


Subject(s)
Cattle/physiology , Meat/economics , Meat/standards , Models, Economic , Animals , Body Weight , Commerce/methods , Female , Linear Models , Male , Models, Statistical , Quality Control , United States
5.
J Anim Sci ; 89(5): 1474-83, 2011 May.
Article in English | MEDLINE | ID: mdl-21239660

ABSTRACT

A survey was conducted to quantify incidence of Beef Quality Assurance (BQA)-related defects in market beef and dairy cows and bulls selling at auction during 2 seasons in 2008. Twenty-three BQA-related traits were evaluated by 9 trained personnel during sales at 10 livestock auction markets in Idaho (n = 5; beef and dairy), California, (n = 4; dairy only), and Utah (n = 1; beef and dairy). Overall, 18,949 unique lots (8,213 beef cows, 1,036 beef bulls, 9,177 dairy cows, and 523 dairy bulls,) consisting of 23,479 animals (9,299 beef cows, 1,091 beef bulls, 12,429 dairy cows, and 660 dairy bulls) were evaluated during 125 sales (64 spring, 61 fall) for dairy and 79 sales (40 spring, 39 fall) for beef. The majority of market beef cows and bulls (60.9 and 71.3%, respectively) were predominantly black-hided, and the Holstein hide pattern was observed in 95.4 and 93.6% of market dairy cows and bulls, respectively. Market cattle weighed 548 ± 103.6 kg (beef cows), 751 ± 176.1 kg (beef bulls), 658 ± 129.7 kg (dairy cows), and 731 ± 150.8 kg (dairy bulls). Most beef cows (79.6%) weighed 455 to 726 kg, and most beef bulls (73.8%) weighed 545 to 954 kg, respectively. Among market beef cattle, 16.0% of cows and 14.5% of bulls weighed less than 455 and 545 kg, respectively, and 63.7% of dairy cows and 81.5% of dairy bulls weighed 545 to 817 kg or 545 to 954 kg, respectively. However, 19.5% of dairy cows and 13.1% of dairy bulls weighed less than 545 kg. Mean BCS for beef cattle (9-point scale) was 4.7 ± 1.2 (cows) and 5.3 ± 0.9 (bulls), and for dairy cattle (5-point scale) was 2.6 ± 0.8 (cows) and 2.9 ± 0.6 (bulls). Some 16.5% of beef cows and 4.1% of beef bulls had a BCS of 1 to 3, whereas 34.8% of dairy cows and 10.4% of dairy bulls had a BCS of 2 or less. Emaciation (beef BCS = 1, dairy BCS = 1.0) or near-emaciation (beef BCS = 2, dairy BCS = 1.5) was observed in 13.3% of dairy cows and 3.9% of beef cows. Among beef cattle, 15.1% of cows and 15.4% of bulls were considered lame. In contrast, 44.7% of dairy cows and 26.1% of dairy bulls were lame. Ocular neoplasia (cancer eye) was observed in only 0.6% of beef cows, 0.3% of beef bulls, 0.3% of dairy cows, and 0.0% of dairy bulls. However, among animals with ocular neoplasia, it was cancerous in 34.4% of beef bulls, 48.0% of dairy cows, and 73.3% of beef cows. In conclusion, numerous quality defects are present in market beef and dairy cattle selling at auction in the Western United States, which could influence their value at auction.


Subject(s)
Cattle/physiology , Meat/standards , Animals , Female , Incidence , Male , Meat/economics , Quality Control , United States/epidemiology
6.
Nanoscale Res Lett ; 4(4): 313-320, 2009 Apr.
Article in English | MEDLINE | ID: mdl-20596342

ABSTRACT

The article reports on structure, mechanical, optical, photocatalytic and biocidal properties of Ti-Ag-O films. The Ti-Ag-O films were reactively sputter-deposited from a composed Ti/Ag target at different partial pressures of oxygen pO(2) on unheated glass substrate held on floating potential U(fl). It was found that addition of ~2 at.% of Ag into TiO(2) film has no negative influence on UV-induced hydrophilicity of TiO(2) film. Thick (~1,500 nm) TiO(2)/Ag films containing (200) anatase phase exhibit the best hydrophilicity with water droplet contact angle (WDCA) lower than 10° after UV irradiation for 20 min. Thick (~1,500 nm) TiO(2)/Ag films exhibited a better UV-induced hydrophilicity compared to that of thinner (~700 nm) TiO2/Ag films. Further it was found that hydrophilic TiO(2)/Ag films exhibit a strong biocidal effect under both the visible light and the UV irradiation with 100% killing efficiency of Escherichia coli ATCC 10536 after UV irradiation for 20 min. Reported results show that single layer of TiO(2) with Ag distributed in its whole volume exhibits, after UV irradiation, simultaneously two functions: (1) excellent hydrophilicity with WDCA < 10° and (2) strong power to kill E. coli even under visible light due to direct toxicity of Ag.

7.
Exp Parasitol ; 119(2): 246-51, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18343372

ABSTRACT

The potential role of phospholipases in trypanosomiasis was investigated using bee venom phospholipase A2 (bvPLA2) as a model. The effects of bvPLA2 on the survival of Trypanosoma brucei brucei, 2h and 12h cultures of Enterobacter cloacae, Escherichia coli, Citrobacter freundii were studied. About 1 mg ml(-1) bvPLA2 was trypanocidal after 30 min. Some growth occurred at lower concentrations up to 2h after treatment but viability decreased up to 8h. Even very low concentrations of bvPLA2 (10(-12) mg ml(-1)) had some trypanocidal activity. Bee venom PLA2 was bactericidal to 2h bacterial cultures but bacteriostatic to 12h ones. Minimum bactericidal concentrations were 10(-5)-10(-6) mg ml(-1). The results showed that bvPLA2 had significant trypanocidal and antibacterial effects on Gram-negative bacteria. The relationship to events occurring during infection is discussed. Phospholipases may play a role in increased endotoxin levels in trypanosomiasis.


Subject(s)
Bee Venoms/enzymology , Enterobacteriaceae/drug effects , Phospholipases A2/pharmacology , Trypanosoma brucei brucei/drug effects , Animals , Bees , Citrobacter freundii/drug effects , Citrobacter freundii/growth & development , Enterobacter cloacae/drug effects , Enterobacter cloacae/growth & development , Enterobacteriaceae/growth & development , Escherichia coli/drug effects , Escherichia coli/growth & development , Microbial Sensitivity Tests , Parasitic Sensitivity Tests , Trypanosoma brucei brucei/growth & development
8.
Caries Res ; 41(5): 342-9, 2007.
Article in English | MEDLINE | ID: mdl-17713333

ABSTRACT

The minimum inhibitory concentrations (MIC) of commercially available and 70% aqueous propanone (P70) extracts from plants chosen for polyphenol content on Streptococcus mutans and other bacteria were determined using a standard susceptibility agar dilution technique to investigate their potential use as anticariogenic agents. The effects on adhesion of S. mutans to glass were also studied. The lowest MICs were for the P70 extracts of red grape skin (0.5 mg ml(-1)) and green tea and sloe berry skin (2 mg ml(-1)). The commercial extracts generally had a lower activity with a minimum MIC of 2 mg ml(-1) for tea extracts, grape seed extracts and Pynogenol (extract of maritime pine). All other extracts had MICs of > or = 4 mg ml(-1). Unfermented cocoa had greater antimicrobial activity than fermented cocoa and the activity of the fractionated extract increased with the extent of epicatechin polymerization. Epicatechin polymer had an MIC of 1 mg ml(-1) and an MBC of 64 mg ml(-1). Selected extracts were tested against other oral bacteria and showed activity against gram-positive organisms. P70 extracts of unfermented cocoa, epicatechin polymer fraction, green tea and red grape seed were bacteriostatic and prevented acid production when added at the MIC to cultures of S. mutans grown in a chemically defined medium supplemented with either glucose or sucrose. There was a reduction in viability which was greater when added to washed cells, but there were some viable cells after 24 h. The extracts also reduced adherence of S. mutans to glass.


Subject(s)
Anti-Bacterial Agents/pharmacology , Flavonoids/pharmacology , Phenols/pharmacology , Plant Extracts/pharmacology , Streptococcus mutans/drug effects , Anti-Bacterial Agents/chemistry , Bacterial Adhesion/drug effects , Cacao , Dental Caries/microbiology , Dental Caries/prevention & control , Grape Seed Extract , Microbial Sensitivity Tests , Plant Extracts/chemistry , Polyphenols , Proanthocyanidins/pharmacology , Tea , Time Factors
9.
Burns ; 33(3): 334-40, 2007 May.
Article in English | MEDLINE | ID: mdl-17234351

ABSTRACT

The aims of the study were to determine the sites in a pediatric burns unit that were contaminated with Staphylococcus aureus. Samples from the environment in bedrooms and the common room were taken monthly for 6 months using blood agar for total counts and Baird-Parker agar for S. aureus. The air was sampled using an air-sampling device and settle plates. Hard and soft surfaces including bed, blanket, sofa, chair, taps, bathtub, soft toys, locker and cupboard in the same rooms were sampled using contact plates. Swabs were taken from staff monthly for 3 months. S. aureus isolates were tested for production of enterotoxins A-D and toxic shock syndrome toxin-1 using a reverse passive latex agglutination test. The results showed that S. aureus was recovered more frequently using settle plates than using the air sampler. All surfaces sampled were contaminated with S. aureus and contamination was greatest in frequently occupied rooms. A variety of toxin producing isolates were found with enterotoxin C isolates, either alone or in combination with TSST-1 (toxic shock syndrome toxin-1) dominant. The staff were transiently colonised with S. aureus strains with a different toxin production pattern. The results show that airborne transmission may be a route for infection by S. aureus and is responsible for contaminating the environment.


Subject(s)
Bacterial Toxins/metabolism , Burn Units , Burns/microbiology , Cross Infection/microbiology , Staphylococcal Infections/metabolism , Staphylococcus aureus/isolation & purification , Air Microbiology , Burns/metabolism , Child , Cross Infection/metabolism , Drug Resistance , Equipment Contamination , Humans , Microbial Sensitivity Tests/methods , Personnel, Hospital , Staphylococcus aureus/metabolism
10.
J Microbiol Methods ; 54(3): 353-8, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12842481

ABSTRACT

The purpose of this study was to examine the use of Chromocult agar medium for isolation and enumeration of Enterobacteriaceae from human faecal samples, to compare it to MacConkey agar and to evaluate its usefulness as a possible alternative selective medium in human faecal studies. The medium was shown to be effective in identifying Escherichia coli and coliforms in faeces without the need for extensive accompanying biochemical tests for confirmation of identity. A positive correlation (r=0.86) was found between the recovery of Enterobacteriaceae on the two media, and no significant difference (P>0.05) between overall mean bacterial counts for the whole study group or at different intervals of faecal collection were observed. Chromocult agar is an effective replacement for MacConkey agar in human faecal studies and has the advantage of differentiating E. coli from other coliforms.


Subject(s)
Agar , Bacteriological Techniques/methods , Chromogenic Compounds , Escherichia coli Infections/microbiology , Escherichia coli/isolation & purification , Feces/microbiology , Colony Count, Microbial , False Negative Reactions , False Positive Reactions , Humans
11.
Lett Appl Microbiol ; 36(6): 372-6, 2003.
Article in English | MEDLINE | ID: mdl-12753244

ABSTRACT

AIMS: To develop a competitive agglutination inhibition assay (CAIA) for the detection of anti-Toxic Shock Syndrome Toxin-1 (TSST-1) antibody in serum samples using a commercially available reverse passive agglutination assay (RPLA) kit. METHODS AND RESULTS: TSST-1 toxin and sera were incubated together, so that anti-toxin IgG would complex with the toxin. Latex particles sensitized with rabbit IgG anti-TSST-1 were added to test for un-complexed toxin. The sensitivity and specificity of the CAIA assay was determined relative to positive and negative ELISA results. The sensitivity (proportion of positive ELISA sera which tested positive by CAIA) was 66% whilst the specificity (proportion of ELISA negative sera which tested negative by CAIA) was 75%. Seven sera (14%) were negative by ELISA but positive for CAIA and 12 (18.8%) were positive for ELISA but negative for CAIA, suggesting some interference with the assays. Statistical analysis showed no significant difference between the methods in terms of the numbers of individuals testing positive (chi2, P = 0.04). CONCLUSIONS: The CAIA assay allowed detection of anti-TSST-1 within 18 h and was simple to read visually. SIGNIFICANCE AND IMPACT OF THE STUDY: The method is a useful test for individual serum samples and a preliminary investigation for medical screening of suspected toxic shock syndrome and is applicable in situations where antibody assays are not routinely used for anti-TSST-1 and also where sophisticated equipment (e.g. microtitre plate reader) is not available.


Subject(s)
Antibodies, Bacterial/blood , Bacterial Toxins , Enterotoxins/immunology , Serologic Tests/methods , Shock, Septic/diagnosis , Staphylococcus aureus/immunology , Superantigens , Animals , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Humans , Latex Fixation Tests , Rabbits , Reagent Kits, Diagnostic , Sensitivity and Specificity , Staphylococcal Infections/diagnosis , Staphylococcus aureus/metabolism
12.
J Appl Microbiol ; 94(3): 413-20, 2003.
Article in English | MEDLINE | ID: mdl-12588550

ABSTRACT

AIMS: To determine the ability of 149 clinical isolates of Staphylococcus aureus from burns, other wounds and environmental isolates to adhere to immobilized proteins. METHODS AND RESULTS: The ability to bind to immobilized fibrinogen, fibronectin, laminin, collagen, IgG and lysozyme was studied using a microtitre plate assay. The strains were very diverse. Binding to fibrinogen was most frequent, followed by fibronectin, collagen and laminin. Binding to IgG and lysozyme was weak and few strains showed strong binding. Numerical analysis showed that 65% of the strains infecting burns had similar properties and bound to fibrinogen, fibronectin, collagen and IgG. The strains infecting other wounds had more variable characteristics. CONCLUSIONS: The ability to adhere to proteins is important in wound infection, but clinical isolates were diverse in their ability to bind to the proteins tested. Burn wounds were more likely to be infected with strains showing multiple binding characteristics. SIGNIFICANCE AND IMPACT OF THE STUDY: The study confirms the importance of adhesins in clinical infection.


Subject(s)
Proteins/physiology , Staphylococcus aureus/physiology , Wounds and Injuries/microbiology , Bacterial Adhesion/physiology , Burns/microbiology , Collagen/physiology , Fibrinogen/physiology , Fibronectins/physiology , Humans , Immunoglobulin G/physiology , Laminin/physiology , Muramidase/physiology , Protein Binding/physiology , Wound Infection/microbiology
13.
J Med Microbiol ; 51(1): 50-55, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11800472

ABSTRACT

The effects of subinhibitory concentrations of silver sulphadiazine (AgSD) on exoprotein production in Staphylococcus aureus strains T1, T4, RN4282 and RN 4282agr were studied. AgSD markedly increased levels of toxic shock syndrome toxin (TSST)-1 in strains T4 and RN4282. This effect was independent of agr and AgSD restored TSST-1 production to the wild-type level in RN 4282agr. AgSD had no effect on enterotoxin A or coagulase activity in strains T1 or T4. Strain T4 produced enterotoxin C at high levels and no effect was observed with AgSD. AgSD repressed metalloprotease production in strain T4 but the overall protease activity remained the same. No change in proteolytic activities was seen in strainT1 with AgSD. Molecular mechanisms for these observations are discussed.


Subject(s)
Anti-Infective Agents, Local/pharmacology , Bacterial Toxins , Enterotoxins/biosynthesis , Shock, Septic/microbiology , Silver Sulfadiazine/pharmacology , Staphylococcus aureus/metabolism , Superantigens , Coagulase/metabolism , Endopeptidases/metabolism , Staphylococcus aureus/drug effects
14.
Int J Food Microbiol ; 68(3): 173-86, 2001 Sep 01.
Article in English | MEDLINE | ID: mdl-11529440

ABSTRACT

The wide variety and the socio-economic and dietary importance of traditional fermented milk products of Ethiopia are discussed in this paper. Information on the microbiology of these products is sparse and has relevance to those organisms associated with spoilage and to those considered desirable for fermentation. There is a clear need to improve the production of African foods and beverages [Int. J. Food Microbiol. 18 (1993) 85]. The objective of this review was to document traditional technology used and information on the microbiology of the products, and to identify various constraints to the development and commercialisation of fermented milk products. Thereby the major problems and potential areas for improvement are pointed out. Ergo, the most important traditional product resembles yoghurt and, as the other traditional products, is prepared by "spontaneous" fermentation, commonly initiated by either "back slopping" or by repeated use of the same utensil. Other products include traditional fermented curd or ititu, traditional butter or kibe, neter kibe or traditional ghee, ayib resembling cottage cheese, arrera or defatted buttermilk and augat or traditional whey.


Subject(s)
Dairy Products/microbiology , Food Contamination/prevention & control , Food Handling/methods , Animals , Ethiopia , Fermentation , Humans , Lactobacillus/metabolism , Milk/microbiology , Socioeconomic Factors
15.
Vet Microbiol ; 68(1-2): 127-30, 1999 Aug 16.
Article in English | MEDLINE | ID: mdl-10501169

ABSTRACT

The V4 thermostable Newcastle disease vaccine was tested under village conditions in Central Tanzania. The vaccination regimes were four vaccinations by eye drop (eye drop group), one vaccination by eye drop followed by three vaccinations by drinking water (drinking water group), one vaccination by eye drop followed by three vaccinations with vaccine supplied on boiled sorghum (food vaccine group) and no vaccine (control group). Antibody responses in the eye drop and drinking water groups suggested that at least 70% of the chickens would be protected against challenge with virulent virus. In both groups, eight of the 11 chickens survived laboratory challenge. Only three of the 11 chickens in the food vaccine group resisted challenge, and none of the 10 control chickens.


Subject(s)
Chickens , Newcastle Disease/prevention & control , Newcastle disease virus/immunology , Vaccination/veterinary , Viral Vaccines/administration & dosage , Administration, Oral , Animal Feed , Animals , Antibodies, Viral/blood , Drinking , Hemagglutination Inhibition Tests/veterinary , Hot Temperature , Newcastle Disease/immunology , Ophthalmic Solutions , Rural Population , Tanzania , Viral Vaccines/immunology , Viral Vaccines/standards
16.
J Med Microbiol ; 47(10): 923-8, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9788817

ABSTRACT

Twenty isolates resembling viridans streptococci, 16 from blood and four from gastric aspirates, from 17 cases of early onset neonatal sepsis were identified by the API20 Strep, Rapid ID 32 Strep and conventional tests plus hydrolysis of methylumbelliferyl glycoside substrates. Nineteen of the isolates were identified as species of viridans streptococci and one as a Leuconostoc sp. Ten of the isolates were Streptococcus oralis, three S. mitis biotype 1, two S. mitis biotype 2 and one each of S. sanguis, S. vestibularis, S. salivarius and S. intermedius. The Rapid ID 32 Strep and conventional plus methylumbelliferyl tests gave the same species identity for 17 of the isolates. S. intermedius was identified by the Rapid ID 32 Strep as S. constellatus and S. salivarius as S. equinus, with S. salivarius at lower probability. The API20 Strep failed to identify S. vestibularis and identified S. salivarius as S. defectivus. The absence of certain critical tests, including urea hydrolysis, does not allow the API20 Strep to identify all the currently recognised species of viridans steptococci. The species distribution was unexpected and the incidence of S. oralis and other viridans streptococci in vaginal swabs from prenatal patients is being investigated further.


Subject(s)
Bacteremia/microbiology , Stomach/microbiology , Streptococcal Infections/microbiology , Streptococcus/classification , Glycosides/metabolism , Humans , Hydrolysis , Hymecromone/analogs & derivatives , Hymecromone/metabolism , Infant, Newborn , Streptococcus/metabolism
17.
J Med Microbiol ; 45(6): 501-4, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8958257

ABSTRACT

Seventy-eight clinical isolates and four control strains of viridans streptococci were tested in parallel for arginine hydrolysis by five different methods. These comprised two commercial systems, the API20 STREP and Vitek GPI card, two published methods, one based on ammonia production and one on alkalisation of Møeller's decarboxylase medium, and a method based on alkalisation of a phenol-red broth medium dispensed into microtitration plates. The clinical isolates were speciated by their biochemical reactions in the API20 STREP and API20 ZYM systems. One strain produced only a weak reaction for arginine hydrolysis in the medium by ammonia production, but otherwise the results with this medium, the API20 STREP and the microtitration plate method were identical. Tests with the Møeller decarboxylase medium and Vitek GPI card gave negative results with isolates that were positive by other methods. Inoculum size was shown to influence arginine hydrolysis obtained with Streptococcus sanguis NCTC 7863 and S. milleri 10713.


Subject(s)
Arginine/metabolism , Streptococcus/metabolism , Adult , Bacterial Typing Techniques , Humans , Hydrolysis , Infant , Infant, Newborn , Software , Streptococcus/classification , Streptococcus/isolation & purification
18.
Burns ; 22(5): 384-9, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8840039

ABSTRACT

This study aimed to determine whether strains of Staph. aureus isolated from children on our paediatric burns unit were different from strains isolated from other patient groups. Of particular interest was the incidence of toxin production amongst the different patient groups and the potential association with toxic shock syndrome (TSS). Wound isolates of Staph. aureus were collected from three patient groups: (1) hospital inpatients, (2) community patients and (3) patients from a regional burns unit. One hundred isolates were collected from each group (n = 300). Each isolate was tested for enterotoxin and TSST-1 production, phage type, antibiogram and tryptophan dependence. The results were compared, to determine whether there were any differences between the isolates from each of these patient groups. There were some variations in antibiotic sensitivity patterns and phage type of the isolates between the different patient groups but there was no significant difference in the incidence of toxin production, which was an important observation. The 100 isolates collected from this burns unit were derived from 58 patients. The colonization patterns of the Staph. aureus showed that 12 patients were colonized by more than one isolate and that these were a mixture of toxin-positive and toxin-negative strains. The medical records were examined for evidence of TSS; there was a higher incidence of toxic episodes in the patients colonized with strains which produced TSST-1 toxin.


Subject(s)
Burn Units , Burns/microbiology , Hospital Departments , Staphylococcal Infections/drug therapy , Staphylococcus aureus , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacterial Typing Techniques , Child , Child, Preschool , Humans , Microbial Sensitivity Tests , Phenotype , Staphylococcal Infections/diagnosis , Staphylococcal Infections/physiopathology , Staphylococcus aureus/classification , Staphylococcus aureus/isolation & purification
19.
J Med Microbiol ; 41(6): 408-13, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7966218

ABSTRACT

Three hundred isolates of Staphylococcus aureus from wound swabs were examined for the production of toxic shock syndrome toxin 1 (TSST-1). The isolates were collected from community patients, surgical inpatients and from patients in the Regional Burns Unit, Booth Hall Children's Hospital, Manchester. The overall incidence of toxin production was 17% and there was no significant variation between the sources of the strains. All 55 TSST-1-producing strains were grown in sublethal concentrations of five topical antimicrobial compounds and the level of toxin produced was determined and compared with the amount produced in a control broth after incubation for 24 h. The effects of sublethal concentrations of the compounds on TSST-1 production were strain dependent; some compounds tended to increase production (at least four-fold) and some tended to decrease production (at least four-fold). Some of the strains showed an increase in toxin production in the presence of chlorhexidine gluconate/cetrimide solution and silver sulphadiazine cream whereas 18%, 42% and 47% of the strains showed a decrease in toxin production in the presence of povidone iodine solution, stabilised hydrogen peroxide cream and mupirocin ointment, respectively. Preliminary results suggest that silver sulphadiazine cream induces toxin formation earlier in the growth cycle.


Subject(s)
Anti-Infective Agents, Local/pharmacology , Bacterial Toxins , Enterotoxins/biosynthesis , Shock, Septic/microbiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/drug effects , Superantigens , Cetrimonium , Cetrimonium Compounds/pharmacology , Chlorhexidine/analogs & derivatives , Chlorhexidine/pharmacology , Colony Count, Microbial , Humans , Hydrogen Peroxide/pharmacology , Mupirocin/pharmacology , Povidone-Iodine/pharmacology , Silver Sulfadiazine/pharmacology , Staphylococcus aureus/growth & development , Staphylococcus aureus/metabolism
20.
Microbios ; 73(296): 173-84, 1993.
Article in English | MEDLINE | ID: mdl-8469176

ABSTRACT

Chloroform extracts of the culture supernatant of a strain of Myxococcus fulvus isolated from soil were fungistatic and prevented germination of spores of Botrytis cinerea. The antibiotics were produced during the exponential phase of growth and the effects of altering medium composition are described. The activity was fractionated into neutral, acidic and basic fractions. The neutral fraction had a molecular weight of 244 and was tentatively identified as 11-phenyl-undecadiene-2-ol. The acidic fraction was primarily n-hexadecanoic acid. The basic fraction contained components [N-(2-phenylethyl)-acetamide, and compounds tentatively identified as 1-isoquinoline carbonitrile and substituted quinolines] which have not previously been described in the myxobacteria.


Subject(s)
Antifungal Agents/biosynthesis , Mitosporic Fungi/drug effects , Myxococcus/metabolism , Antifungal Agents/adverse effects , Antifungal Agents/chemistry , Mitosporic Fungi/cytology , Mitosporic Fungi/growth & development , Spores, Fungal/cytology , Spores, Fungal/drug effects , Spores, Fungal/growth & development
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