Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “isolation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources
PubMed2005

The prevalence of fecal colonization of enterococci, the resistance of the isolates to ampicillin, vancomycin, and high-level aminoglycosides, and the clonal relationship among isolates.

The gastrointestinal tract carriage of enterococci was searched in 150 hospitalized patients and 100 outpatients, and clonal relatedness of the isolates and their resistance to ampicillin, vancomycin, and high-level streptomycin and gentamicin were investigated. A stool sample or rectal swab collected from each patient was inoculated into appropriate media within an hour. Enterococcus species were identified by using conventional biochemical tests, API-20 Strep assay, and BBL crystal kit. Antibiotic susceptibility tests were performed using Kirby-Bauer disk diffusion method. A polymerase chain reaction (PCR) was used to detect vanA and vanB genes. Pulsed-field gel electrophoresis (PFGE) and arbitrarily primed-polymerase chain reaction (AP-PCR) methods were used for molecular typing of the strains. Enterococci were isolated from 90 (60%) of the specimens collected from 150 inpatients. Of these 90 isolates, 37 (41%) had high-level gentamicin resistance, 36 (40%) had high-level streptomycin resistance, and 50 (55.6%) had ampicillin resistance. Fecal colonization was found in 30% of the outpatients. Resistances to ampicillin, high-level streptomycin, and gentamicin were 13%, 10%, and 3%, in these patients' isolates, respectively. No vancomycin-resistant enterococci were detected by both agar diffusion and PCR assays in our study. Both typing procedures were applied on 78 Enterococcus strains isolated from inpatients. AP-PCR typing showed that 30 (50.8%) of the 59 E. faecium and 5 (50%) of the 10 E. faecalis strains were clonally related. These values were found to be 12 (20.3%) and two (20%) by PFGE, respectively. The typing procedures did not find any clustered strains in the six E. durans and three E. avium isolates. Neither PFGE nor AP-PCR result was significantly different among the sensitive and resistant strains. Our results indicate that the high prevalence of colonization with ampicillin and highlevel aminoglycoside-resistant enterococci is an important problem in our medical center. The high clonal diversity among the isolates indicates limited spread of antibiotic-resistant strains between patients.

Aminoglycosides↗
PubMed2003

Stranded in isolation: structural role of isolated extended strands in proteins.

Reasons for the formation of extended-strands (E-strands) in proteins are often associated with the formation of beta-sheets. However E-strands, not part of beta-sheets, commonly occur in proteins. This raises questions about the structural role and stability of such isolated E-strands. Using a dataset of 250 largely non-homologous and high-resolution (<2 A) crystal structures of proteins, we have identified 518 isolated E-strands from 187 proteins. The two most distinguishing features of isolated E-strands from beta-strands in beta-sheets are the high preponderance of prolyl residues occuring in isolated E-strands and their high exposure to the surroundings. Removal of regions with polyproline conformation from the dataset did not significantly reduce the propensity of prolyl residues to occur in isolated E-strands. Isolated E-strands are often characterized by their main-chain amide and carbonyl groups involved in hydrogen bonding with polar side chains or water. They are often flanked by irregular loop structures and are less well conserved, than beta-sheet forming beta-strands, among homologous protein structures. It is suggested that isolated beta-strands have many characteristics of loop segments but with repetitive (phi,psi) values falling within the beta-region of the Ramachandran map.

Crystallography, X-Ray↗
PubMedDate not supplied

An unusual repetitive element from highly virulent isolates of Leptosphaeria maculans and evidence of its transfer to a weakly virulent isolate.

A 5,238-bp repetitive DNA element from a highly virulent isolate of Leptosphaeria maculans has been cloned and sequenced. The element is present in approximately 80 copies per haploid genome and hybridizes to every chromosome resolved by pulse field gel electrophoresis. The sequence is composed of 66% A+T and has numerous, very short, direct and inverted repeats. No RNA complementary to the element was detected in log phase cultures, and no open reading frames of significant length are present in the sequence. It has no structural similarity to other repetitive elements or significant homology to database sequences. We have designated the element LMR1. Southern blot hybridization indicated that the element is present in all isolates of L. maculans that are highly virulent to Brassica napus and B. rapa. The general structure of the element was conserved among isolates of different mating type, pathogenicity group, and geographic origin, as determined by both Southern blot analysis and primer-directed DNA amplification. LMR1 did not hybridize to DNA from weakly virulent strains of L. maculans, with the exception of one isolate. Phylogenetic analyses of restriction fragment length polymorphism and rDNA sequence indicated that the highly virulent and weakly virulent strains of L. maculans are not monophyletic. Therefore, the presence of the LMR1 element in a weakly virulent isolate may indicate that a rare transfer event has occurred. Surprisingly, the weakly virulent isolate that contains LMR1 is more pathogenic on B. napus and B. juncea than a similar isolate that lacks the element.

Ascomycota↗
PubMed2006

Are clinical isolates of Pseudomonas aeruginosa more virulent than hospital environmental isolates in amebal co-culture test?

OBJECTIVE: Pseudomonas aeruginosa is an important opportunistic pathogen in hospital-acquired infections. As an environmental bacterium, it colonizes soil and water as well as hospital water supply and shares its natural habitat with free-living amebae. It has been shown previously that an ameba host system can be used to analyze the virulence of P. aeruginosa strains. In this study we have developed a simple amebal co-culture test with Acanthamoeba polyphaga to compare the virulence of P. aeruginosa between human and environmental isolates. DESIGN: Experimental study. SETTING: The four state hospitals Intensive of Marseille. INTERVENTIONS: Eighty-one environmental strains isolated from the hospital water and 69 clinical isolates of P. aeruginosa (52 from blood cultures and 17 from bronchoalveolar lavage) were tested in the amebal co-culture test. MEASUREMENTS AND MAIN RESULTS: The results show that compared with environmental isolates, the isolates of P. aeruginosa from blood cultures were significantly more virulent in the ameba assay (37% vs. 62%, p=.006). CONCLUSIONS: These data suggest that clinical infections due to Pseudomonas aeruginosa are due, at least in part, to bacterial virulence. Furthermore, even within the constraints of small sample size, virulence of respiratory isolates is significantly correlated with the occurrence of P. aeruginosa bacteremia. Our results, as those published previously, suggest that at the strain level, acquisition of antimicrobial resistance is correlated with the diminution of virulence. However, at the population level, clinical isolates are more virulent as well as more frequently resistant to antibiotics, presumably due to acquisition of strains mostly through cross-contaminations.

Acanthamoeba↗
PubMed2000

Phylogenetic analysis of 18 thermophilic Methanobacterium isolates supports the proposals to create a new genus, Methanothermobacter gen. nov., and to reclassify several isolates in three species, Methanothermobacter thermautotrophicus comb. nov., Methanothermobacter wolfeii comb. nov., and Methanothermobacter marburgensis sp. nov.

Using a combination of 16S rRNA analysis and antigenic fingerprinting consisting of new and published data, the phylogenetic position of 18 thermophilic isolates currently classified as Methanobacterium species was reinvestigated. The results were verified by independent methods, including, where applicable, plasmid and phage typing. Comparative analysis of 16S rRNA data for 30 strains belonging to the order Methanobacteriales strongly suggested that mesophilic and thermophilic Methanobacterium isolates are distantly related and should be assigned to separate genera. For the thermophilic strains the genus Methanothermobacter was initially proposed by Boone, Whitman and Rouvière. Furthermore, the results support a reclassification of 15 isolates in three species within the proposed genus: (i) Methanothermobacter thermautotrophicus comb. nov., containing eight isolates, six of which are able to utilize formate (type strain deltaHT); (ii) Methanothermobacter wolfeii comb. nov., containing four formate-utilizing isolates (type strain DSM 2970T); (iii) Methanothermobacter marburgensis sp. nov., containing three obligately autotrophic isolates (type strain MarburgT). Of the nine isolates formerly referred to as Methanobacterium thermoformicicum, six were reclassified as Methanothermobacter thermautotrophicus and three as Methanothermobacter wolfeii.

Antigens, Archaeal↗
PubMed1992

The complete nucleotide sequence of RNA 1 of a German isolate of barley yellow mosaic virus and its comparison with a Japanese isolate.

The nucleotide sequence of RNA 1 of a German isolate of barley yellow mosaic virus has been determined and compared with a Japanese isolate of the same virus. The sequence identity is 93.6% at the nucleotide level and 96% at the amino acid level. Similar values have been found for the polyproteins of the RNA 2 of both isolates (95%). Both isolates show an RNA 1-encoded protein arrangement similar to that of potyviruses such as tobacco etch virus. In contrast, the polyproteins of the small RNAs (RNA 2) do not show such a similarity to the polyproteins of other potyviruses. However, there is a striking difference between the two isolates in the generally highly conserved active site of the RNA-dependent RNA polymerase. The German isolate exactly matches the consensus sequences for previously described potyviral RNA-dependent RNA polymerases, whereas the Japanese isolate does not.

Amino Acid Sequence↗
PubMed1998

Four DNA-A variants among Pakistani isolates of cotton leaf curl virus and their affinities to DNA-A of geminivirus isolates from okra.

Complete DNA-A sequences of nine Pakistani geminivirus isolates from leaf curl-affected cotton (CLCuV-PK) or from okra, and the partial sequences of several additional isolates were determined. Sequences of isolates from cotton were of four types. Isolates from leaf curl-affected okra had virtually the same sequences as those from cotton. Isolates from yellow vein mosaic-affected okra were of two types (OYVMV types 201 and 301), both distinct from but closely related to the virus isolates from cotton. Of these six types, two types of CLCuV-PK are the most closely related but another (CLCuV-PK type 72b) is the most distinct. Of the encoded proteins, coat protein (CP) is the most strongly conserved (92-100% amino acid sequence identity), and AC4 protein the most variable (41-87%). The 5' and 3' halves of the intergenic region of some isolates had different affinities and occurred in seven combinations, suggesting that recombination had occurred and that the origin of replication was a favoured recombination site. Similarly, the first 1520 nt of CLCuV-PK type 804a DNA resembled those of OYVMV type 301 DNA but the remaining 1224 nt were very different. The AC1 (Rep) gene and 5' part of the intergenic region of CLCuV-PK type 72b closely resembled those of OYVMV type 301, whereas the rest of the sequence did not. The cotton leaf curl epidemic in Pakistan is caused by several distinct variants, with recombination events involving OYVMV and other unspecified geminiviruses having probably been involved in their evolution.

Base Sequence↗
PubMed2000

The entire nucleotide sequence of two hepatitis G virus isolates belonging to a novel genotype: isolation in Myanmar and Vietnam.

A novel genotype of hepatitis G virus (HGV) was recently identified in sera of subjects from countries in South-East Asia. These isolates were recovered from serum of Myanmarese (designated HGV-MY14) and Vietnamese (designated HGV-VT48) subjects, respectively. To characterize the viral genome in more detail, the full-length nucleotide sequence of the two different HGV isolates belonging to the novel genotype was cloned. Both HGV isolates were composed of 9228 nt and had a single open reading frame spanning 8529 nt and encoding 2843 aa residues. The isolates differed from previously reported HGV/GBV-C isolates types 1 to 3 by 13-15% (nucleotide sequence) and 4-6% (amino acid sequence). The putative core region of both isolates was not clearly identifiable as it consisted of only 16 aa residues. Based on phylogenetic analysis of full-length genome sequences and 5'-UTR sequences, HGV-MY14 and HGV-VT48 isolates can be classified as a novel genotype, designated type 4.

Adolescent↗
PubMed1998

Isolation and characterization of enteroaggregative Escherichia coli (EAggEC) by genotypic and phenotypic markers, isolated from diarrheal children in Congo.

OBJECTIVE: To determine the prevalence of enteroaggregative Escherichia coli (EAggEC) in African diarrheal children in Lwiro, Congo, to characterize EAggEC isolates by possible genotypic and phenotypic markers, and to evaluate the EAggEC probe pCVD432 in identifying EAggEC. METHODS: The Hep-2 cell adhesion assay and colony-blot hybridization assays were carried out for the identification of EAggEC. O:H serotyping, biotyping, antibiogram and plasmid-profile analysis were done. To detect the E. coli LT and ST, ELISA tests were used and, for VT, a vero cell assay was used. RESULTS: EAggEC strains were isolated from 56 out of 115 diarrheal children (48.7%): the organism was present alone and presumed to cause diarrhea in 22 (19.1%) cases. The rest of the cases were associated with two or more diarrheagenic E. coli strains. EAggEC strains were isolated from 25% of total diarrheal children (first day of isolation) and 8.86% of age-matched healthy individuals (p<0.03). This isolation rate was significantly higher than the one found for other diarrheagenic E. coli strains. In parallel, we evaluated the sensitivity and specificity of EAggEC probe pCVD432, and found that it had 56% sensitivity with 100% specificity compared with the Hep-2 cell test. EAggEC isolates were characterized by serotyping, biotyping, antibiotic resistance pattern, plasmid profiling and toxin production analysis. They did not produce any one of these classical toxins and nor did they relate to any particular serotypes. Plasmid analysis of the 79 EAggEC isolates (n=315) showed seven different profiles. Ten resistance patterns were identified and 34 strains were sensitive to all drugs. There was no association between plasmid profiles and antibiotic resistance patterns. All 16 classical E. coli biotypes were found in this small EAggEC population. CONCLUSIONS: EAggEC has been emerging as a cause of childhood diarrhea in African children in Congo. From the accumulated data it was found that there is a great heterogeneity in EAggEC populations.

Journal Article↗
PubMed1994

Comparison of a lesion-inducing isolate and a non-lesional isolate of Candida albicans in an immunosuppressed rat model of oral candidiasis.

Two distinct strain-related patterns of organism-host interaction on dorsal tongue of immunocompetent rats have been identified for Candida albicans: some isolates induce mucosal lesions, while other isolates penetrate the keratin layer but do not produce a lesion. This study examined the behavior of each of the two types of isolates in a cyclosporin-immunosuppressed rat model. Groups B (normal) and D (cyclosporin) were orally inoculated with a lesion-inducing isolate of C. albicans, while a non-lesional isolate was given to Groups A (normal) and C (cyclosporin). A typical dorsal tongue lesion developed in 4/18 rats in Group B and in 13/16 in Group D (P = 0.00267). No significant difference in infection rate between the normal and cyclosporin-treated animals was seen for the non-lesional isolate. The lack of a host inflammatory response associated with the non-lesional isolate may represent an ecologic advantage for the organism.

Animals↗
PubMed1991

[Isolation trends on group A streptococci isolated from clinical specimens in hospitals in Saitama, 1979-1989].

On 4,864 group A streptococci isolated from throat culture of patients in hospitals in Saitama from 1979 to 1989, we have done an epidemiological analysis of the T-type detection rates and the T-type epidemic, the monthly isolation rates, and the isolation rates by sex and age of patients. 1. The T-type detection rates of 4,864 isolates of group A streptococci showed type T12 in 22.6%, type T4 in 16.4%, type T1 in 10.8%, type T13 in 8.5%, type T6 in 7.6%, type T28 in 6.9%, type T3 in 6.1% and type T18 in 5.3% etc, and the largest number of isolates was type T12 among 16 T-types. 2. The main epidemic T-type during the investigation was type T12, and it was at the top from 1980 to 1981 and from 1984 to 1985. The others, type T4 was at the top from 1982 to 1983 and from 1983 to 1989, type T3 was in 1986, type T6 was in 1987, and type T1 was in 1988, especially it has been suggested that there are the high epidemic T-types and low epidemic T-types among the T-types of throat group A streptococci. 3. Monthly epidemic pattern of throat group A streptococci in each year showed two small epidemic peaks on March and June, a large epidemic peak from November to December since a turn on August. Further, the monthly epidemic pattern has been repeated every year. 4. Throat group A streptococci isolated from patients occupied 87 per cent by the patients from 0 to 14 years, the peak of age distribution showed by age group from 5 to 7 years. The sexual ratio of male to female was in the ratio 1:0.9. Further, the throat group A streptococci isolated from patients of age greater than 15 years was occupied about 50 per cent by age group from 30 to 39 years. A sexual ratio of male to female in the age group was in the ratio 1:1.8.

Adult↗
PubMed1997

Comparison of the cellular fatty acid composition of a bacterium isolated from a human and alleged to be Bacillus sphaericus with that of Bacillus sphaericus isolated from a mosquito larvicide.

The cellular fatty acid (CFA) composition of the cytoplasmic membrane of a bacillus isolated from a human lung and deposited in the National Collection of Type Cultures as Bacillus sphaericus NCTC 11025 was determined by gas-liquid chromatography. The CFA composition of B. sphaericus 2362, isolated from a microbial larvicide, and those of B. sphaericus reference strains obtained from public collections were also determined. Samples were grouped by hierarchical cluster analysis based on the unpaired-group method using arithmetic averages. Samples that linked at a Euclidean distance of < or = 2.0 U were considered to belong to the same strain. NCTC 11025 and the type strain of B. sphaericus, ATCC 14577, were mixed; all other isolates were monotypic. The predominant fatty acid in NCTC 11025 was 12-methyltetradecanoic acid, while the predominant fatty acid in the remaining isolates was 13-methyltetradecanoic acid. NCTC 11025 linked to the other isolates at a Euclidean distance of 83.8 U, and we concluded that it belongs to a different species that we could not identify. We could distinguish among six DNA homology groups of B. sphaericus by using fatty acids. Within DNA homology group IIA, strain 2362 could be distinguished from other strains belonging to serotype H5a, 5b. We concluded that CFA analysis is a useful technique to determine if future human isolates identified as B. sphaericus in fact belong to other species of bacteria or whether the isolates originated from commercial products.

Animals↗
PubMed2002

Isolation of Shigella dysenteriae type 1 and S. flexneri strains from surface waters in Bangladesh: comparative molecular analysis of environmental Shigella isolates versus clinical strains.

Bacillary dysentery caused by Shigella species is a public health problem in developing countries including Bangladesh. Although, shigellae-contaminated food and drinks are often the source of the epidemic's spread, the possible presence of the pathogen and transmission of it through environmental waters have not been adequately examined. We analyzed surface waters collected in Dhaka, Bangladesh, for the presence of shigellae by a combination of PCR assays followed by concentration and culturing of PCR-positive samples. Analysis of 128 water samples by PCR assays for Shigella-specific virulence genes including ipaBCD, ipaH, and stx1 identified 14 (10.9%) samples which were positive for one or more of these virulence genes. Concentration of the PCR-positive samples by filtration followed by culturing identified live Shigella species in 11 of the 14 PCR-positive samples. Analysis of rRNA gene restriction patterns (ribotype) showed that the environmental isolates shared ribotypes with a collection of clinical isolates, but in contrast to the clinical isolates, 10 of the 11 environmental isolates were either negative or carried deletions in the plasmid-encoded invasion-associated genes ipaB, ipaC, and ipaD. However, all environmental Shigella isolates were positive for the chromosomal multicopy invasion-associated gene ipaH and all Shigella dysenteriae type 1 isolates were positive for the stx1 gene in addition to ipaH. This study demonstrated the presence of Shigella in the aquatic environment and dispersion of different virulence genes among these isolates which appear to constitute an environmental reservoir of Shigella-specific virulence genes. Since critical virulence genes in Shigella are carried by plasmids or mobile genetic elements, the environmental gene pool may contribute to an optimum combination of genes, causing the emergence of virulent Shigella strains which is facilitated in particular by close contact of the population with surface waters in Bangladesh.

Anti-Bacterial Agents↗
PubMed2006

Spoligotyping of Mycobacterium tuberculosis isolates from Pakistan reveals predominance of Central Asian Strain 1 and Beijing isolates.

The estimated incidence of tuberculosis in Pakistan is 181 per 100,000; however, there is limited information on Mycobacterium tuberculosis genotypes circulating in the country. We studied 314 M. tuberculosis clinical isolates; of these, 197 (63%) isolates grouped into 22 different clusters, while 119 (37%) had unique spoligotypes. Eighty-nine percent of the isolates were pulmonary (Pul), and 11% were extrapulmonary (E-Pul). We identified Central Asian Strain (CAS), Beijing, T1, Latin American-Mediterranean, and East African-Indian genogroups. Beijing strains, reportedly the most prevalent spoligotype worldwide, constituted 6% of our strain population. The CAS1 strain comprised 121 (39%) of the study isolates. No difference was observed between clustered isolates from cases of Pul and E-Pul tuberculosis. However, E-Pul isolates included a greater number of unique spoligotypes than Pul isolates (P = 0.005). The overall percentage of drug resistance was 54%, and that of MDR strains was 40%. While CAS1 strains were not associated with drug resistance, the relative risk of MDR was significant in Beijing strains compared to the non-Beijing groups (95% confidence interval, 1.2 to 8.9). The fact that the predominant strain, CAS1, is not associated with drug resistance is encouraging and suggests that an effective tuberculosis control program should be able to limit the high incidence of disease in this region.

Adolescent↗
PubMedDate not supplied

Aneuploidy and isolated mild ventriculomegaly. Attributable risk for isolated fetal marker.

BACKGROUND: Does the prenatal ascertainment of isolated mild ventriculomegaly increase the a priori risk for aneuploidy when isolated or not associated with advanced maternal age? Does isolated mild ventriculomegaly increase the risk for pediatric developmental delay? METHODS: The Wayne State University (WSU) Reproductive Genetics abnormal case data base and the Madigan Army Medical Center (MAMC) experience were reviewed to compare the rates of aneuploidy for cases with fetal ventriculomegaly. Cases were classified by maternal age and associated sonographic markers of aneuploidy. Aneuploidy rates were compared between the isolated ventriculomegaly, ventriculomegaly with advanced maternal age (AMA), and ventriculomegaly associated with multiple anomalies. Rates of aneuploidy were compared to identify association. RESULTS: A total of 118 cases with ventriculomegaly were identified for comparison. Ninety-four cases were identified in the WSU cohort; 46 demonstrated isolated ventriculomegaly alone, and aneuploidy was present in 3/25 (12%) with invasive fetal testing, 0/24 (0%) cases in the MAMC cohort demonstrated aneuploidy. Isolated mild ventriculomegaly cases at MAMC were identified for further tests. DISCUSSION: Although the two study populations vary in age and risk distributions, the attributable risk for isolated mild ventriculomegaly poses a counseling conundrum due to the neurodevelopmental implication of this minor dysmorphism more so than its association with aneuploidy.

Aneuploidy↗
PubMed1992

Isolation and serial propagation of porcine epidemic diarrhea virus in cell cultures and partial characterization of the isolate.

Porcine epidemic diarrhea virus (PEDV) was isolated in Vero cell cultures from the small intestine of a piglet experimentally infected with porcine coronavirus 83P-5, that had been isolated during outbreaks of porcine acute diarrhea and passaged in piglets. The isolation of the PEDV was successful only in Vero cells maintained in the maintenance medium (MM) containing trypsin. Infected Vero cell cultures exhibited CPE characterized by cell-fusion and syncytial formation, as well as cytoplasmic fluorescence when examined by the indirect immunofluorescent test using rabbit anti-83P-5 virus serum. The isolate was adapted to serial propagation in Vero cell cultures by adding trypsin to MM. Vero cell-adapted PEDV was successfully propagated in the MA104, CPK and ESK cell lines in the presence of trypsin in MM. Vero cell-adapted PEDV had morphologic and physicochemical characteristics similar to those of other members of the coronaviridae. The isolate differed serologically from porcine transmissible gastroenteritis (TGE) and porcine hemagglutinating encephalomyelitis viruses, and no antigenic relationship between the isolate and TGE virus could be detected by the indirect immunofluorescent test. Attempts to isolate PEDV in 6 types of primary fetal pig cell cultures and 6 of 10 established cell lines resulted in the failure, probably because these cells were damaged by the action of trypsin.

Animals↗
PubMed1998

Phenotypic and genotypic characterization of Vibrio cholerae isolates from a recent cholera outbreak in Senegal: comparison with isolates from Guinea-Bissau.

A total of 127 strains of Vibrio cholerae (117 V. cholerae O1 and 10 nonagglutinating strains) isolated from a recent cholera outbreak in Senegal and four strains isolated in Guinea-Bissau (during the survey of a cholera epidemic that occurred 10 months before the Senegalese one) were analyzed. Strains were characterized by conventional methods (biochemical and serologic identification, susceptibility to antimicrobial agents), polymerase chain reaction for genes encoding cholera toxin (CtxA), zonula occludens toxin (Zot), and accessory cholera enterotoxin (Ace), and by ribotyping. Conventional methods showed that all strains of V. cholerae O1 belonged to serotype Ogawa, biotype El Tor and were resistant to the vibriostatic agent O129 (2,4-diamino 6,7-diisopropylpteridine phosphate), cotrimoxazole, and chloramphenicol; all strains were sensitive to tetracycline, a drug that has been extensively used in cholera therapy. Most of these V. cholerae O1 (112 strains from Senegal and four strains from Guinea-Bissau) had an intact core region (virulence cassette) and amplified a 564-basepair (bp) fragment of ctxA, a 1083-bp fragment of zot, and a 314-bp fragment of ace. Ribotyping of V. cholerae O1 strains after Bgl I restriction of total DNA revealed that ribotype B5a, which is the predominant ribotype of this seventh pandemic of cholera, was not isolated. Instead, a new ribotype was identified and designated B27 in our data bank. Since O1 isolates from Guinea-Bissau and Senegal have the same biotype, serotype, and ribotype and as the Guinea-Bissau outbreak that preceded the one in Senegal, this emerging ribotype probably came from Guinea-Bissau. Nonagglutinating strains exhibited no resistance to the O129 agent and to the tested antibiotics, they were all negative for virulence cassette, except for one strain with the ctxA and zot genes isolated from a patient with diarrhea, and there was a great variability of ribotypes among these strains. There was no difference between environmental O1 strains isolated from water and strains isolated from patients with cholera, suggesting that fecally contaminated water is an important reservoir for infection.

Bacterial Typing Techniques↗
PubMedDate not supplied

Frequency of isolation and antimicrobial susceptibility patterns of Staphylococcus intermedius and Pseudomonas aeruginosa isolates from canine skin and ear samples over a 6-year period (1992-1997).

Staphylococcus intermedius (S. intermedius) was isolated from 88.6% and 49.4% of skin and ear samples, respectively, during the years 1992 through 1997, and frequency of isolation remained unchanged. More than 95% of all S. intermedius isolates were susceptible to cephalothin and oxacillin, providing support for empirical treatment of canine skin and ear infections with cephalexin. Pseudomonas aeruginosa (P. aeruginosa) was isolated from 7.5% and 27.8% of skin and ear samples, respectively. The frequency of isolation from skin samples increased over the study period. Because of multidrug-resistant profiles for P. aeruginosa isolates, especially for ear isolates, empirical treatment of P. aeruginosa infections is not advisable.

Animals↗