Phage type conversion in Salmonella enterica serotype Enteritidis caused by the introduction of a resistance plasmid of incompatibility group X (IncX)

The plasmid pOG670, a 54 kb, conjugative plasmid that specifies resistance to ampicillin and kanamycin and belonging to the incompatibility group X (IncX), was transferred into 10 isolates of Salmonella enterica serotype Enteritidis belonging to 10 different phage types (PT1, 2, 3, 4, 8, 9, 9b, 10, 11 and 13). Acquisition of the plasmid by these strains did not result in the loss of any resident plasmids but resulted in phage type conversion in 8 of the 10 strains (PT1, 2, 4, 8, 9, 9b, 10 and 11). The observed changes in phage type were found to result from the loss of sensitivity to 3 of the 10 typing phages used (phages 3, 5 and 7). Where the conversion resulted in a change to a defined phage type, both the new and original PTs belonged to the same, previously described, evolutionary lines. Enteritidis PTs 1, 4 and 8, commonly associated with poultry world-wide, were converted to PTs 21, 6 and 13a respectively. The results indicate a different route for phage type conversion Enteritidis from others reported in the literature and, although IncX plasmids are not normally present in PT8 or PT13a, may suggest a possible mechanism/link connecting these phage types.     

Epidemiological analysis of Salmonella enterica Enteritidis isolates in Japan by phage-typing and pulsed-field gel electrophoresis.

Salmonella enterica serotype Enteritidis isolates of phage types (PTs) PT1, PT4, PT13a and PT22 derived from sporadic cases and outbreaks of food poisoning in Japan during 1994 and 1995 were analysed by pulsed-field gel electrophoresis (PFGE). While PT1 strains from 5 different outbreaks showed 14 PFGE patterns, 5 PFGE patterns were observed among PT4 isolates from 5 different outbreaks and 6 independent isolates from imported chicken. Interestingly, 8 out of 9 PT4 strains associated with foreign travel to Southeast Asia were indistinguishable in PFGE pattern from 5 independent isolates of imported chicken from England. Although both PT13a and PT22 were first reported in Japan in 1994, PT22 showed various PFGE patterns compared to PT13a which had the same pattern within an outbreak, unlike PT1. These results could indicate that multiple clonal lines of PT1 and PT22 had already spread while relatively fewer clonal lines of PT4 and PT13a might exist in Japan.     

Variations in biochemical phenotypes and phage types of Salmonella enteritidis in Germany 1980-92.

The Phene Plate system for typing Salmonella serotypes (PhP-S) is a simple automated typing method based on biochemical fingerprinting. It gives a quantitative value of the metabolism of various substrates by measuring the speed and intensity of each reaction. The ''biochemical fingerprint'' of each isolate is used to calculate similarities among the tested strains with a personal computer program. We used this system to examine a collection of 86 strains of Salmonella enteritidis isolated from human sporadic cases in Germany between 1980 and 1992. Twenty-three biochemical phenotypes (BPTs) consisting of 9 common (C) and 14 single (S) BPTs were identified. BPTs C2 and C4 containing 20 and 36 strains respectively accounted for 65% of the isolates. Strains of BPT C2 were found over a wide period of time whereas strains of BPT C4 were isolated during the period between 1988 and 1992. With phage typing, 11 discrete phage types (PTs) and 18 strains designated as non-specific type (NST) were identified. PTs 4 and 8 with 39 and 17 strains respectively were the dominant PTs. Strains of PT 8 were isolated over a wide period of time whereas all (except one) strains of PT 4 were isolated between 1988 and 1992. Combination of biochemical fingerprinting and phage typing divided the strains into 25 phenotypes (BPT:PTs). Whilst phenotype C2:8 was found over a number of different years, phenotype C4:4 was isolated only between 1988 and 1992. These findings indicate the presence of one persistent and one recently emerged phenotype among S. enteritidis strains in Germany.(ABSTRACT TRUNCATED AT 250 WORDS)     

A community-based outbreak of Salmonella enterica serotype Typhimurium associated with salami consumption in Northern Italy.

An outbreak of Salmonella enterica serotype Typhimurium belonging to phage type (PT) 193 occurred in autumn 1995 and involved 83 individuals in a large area of Northern Italy (Lombardy Region). Epidemiological and microbiological investigations of strains isolated from clinical and food specimens revealed that the vehicle was a batch of salami, produced on 4 September 1995 by a local firm. The outbreak was contained when the batch was withdrawn from sale. Insufficient ripening of the salami had allowed the salmonella to survive, emphasizing the need to define criteria for the ripening process of foods such as salami.     

Phage typing and drug resistance of Shigella sonnei isolated in England and Wales.

Phage typing of Shigella sonnei has been used to examine isolates from the 1991-2 sonnei dysentery outbreak in England and Wales and compare them with strains isolated during and following a widespread foodborne outbreak in 1994 which was associated with consumption of imported lettuce. The distribution of phage types was different in the three periods studied with PT 3 predominating during 1991-2, PT 2 during the ''lettuce'' outbreak in the summer months and PT 6 during the subsequent months. PT 6 was frequently associated with travel outside the UK. Variation was also seen in the distribution of drug resistance patterns.     

Occurrence of Salmonella enterica serotype Enteritidis phage types in the Slovak Republic

Phage typing of 741 isolates of Salmonella enterica serotype Enteritidis from the slovak Republic in 1995 has been carried out using the scheme of Ward and colleagues (1987). 202 strains (51 isolated from food) were from 9 outbreaks, 536 isolates were from sporadic cases and 3 isolates were from nosocomial infections of new-born babies. 704 isolates (95%) from all sources were typeable and belonged to 7 different phage types (PTs). PT8 was the phage type most frequently identified (72.6%). Other epidemiologically relevant phage types were PT2 (8.5%), 4 (7.9%) and 1 (4.2%). With an incidence of 1.3--0.1% isolates of PTs 21, 6, 9 were found. 26 (3.5%) isolates were designated RDNC and 11 (1.5%) were untypeable.     

Uniqueness of physical therapy tasks and its relationship to complexity and delegation: a survey of Pennsylvania physical therapists.

Physical therapists' (PTs') perceptions of 26 physical therapy tasks regarding complexity, uniqueness to PTs, and delegation were studied. A questionnaire describing 26 PT tasks was sent to 200 PTs in Pennsylvania identified as working in acute care, rehabilitation, or private practice. The response rate was 45.5%. Eleven of the 26 tasks identified as most unique to PTs were also identified as highly complex. None of these 11 tasks was delegated frequently to a nurse or a PT aide, and only two were delegated to an occupational therapist. All 11 unique tasks were delegated to the physical therapist assistant (PTA), with some level of supervision provided by the majority of respondents. Results indicated there are activities within patient care that are perceived by PTs to be unique to their profession. Also, the role of the PTA may be expanding, warranting further research in this area.     

Correlation of change in phage type with pulsed field profile and 16S rrn profile in Salmonella enteritidis phage types 4, 7 and 9a.

Using pulsed-field gel electrophoresis (PFGE) and 16S rRNA (rrn) analysis (ribotyping), the in vivo derivation of strains of Salmonella enteritidis PTs 9a and 7 from a strain of S. enteritidis PT 4 has been demonstrated. All strains were isolated from a single patient over a 6-week period. Further studies have demonstrated that in terms of pulsed-field profile and ribotype, the genotypes of the patient-derived strains differed from those of the reference strains of the respective phage types. It is concluded that when used in combination, these methods can provide evidence of phylogenetic relationships in apparently unrelated S. enteritidis phage types isolated during pathogenesis of disease.     

Iron restriction and the growth of Salmonella enteritidis.

Strains of Salmonella enteritidis were examined for their ability to remove ferric-ions from the iron chelating agents ovotransferrin, Desferal and EDDA. Growth of S. enteritidis phage type (PT) 4 (SE4) in trypticase soy broth containing ovotransferrin resulted in the expression of iron regulated outer membrane proteins (OMPs) of 74, 78 and 81 kDa, and unexpectedly the repression of expression of OMP C. The 38 MDa ''mouse virulence'' plasmid was not required for the expression of the iron-regulated OMPs (IROMPs). SE4 was able to obtain iron bound to the iron chelator Desferal and EDDA without expressing a high-affinity iron uptake system. Strains of S. enteritidis belonging to PTs 7, 8, 13a, 23, 24 and 30 were also able to remove ferric ions from Desferal and EDDA without expressing a high-affinity iron uptake system. We conclude that strains of SE4 possess a high-affinity iron sequestering mechanism that can readily remove iron from ovotransferrin. It is likely that iron limitation, and not iron restriction, is responsible for the bacteriostatic properties of fresh egg whites.     

Comparison of two Salmonella enteritidis phage typing schemes

The comparison of two phage typing schemes for Salmonella enteritidis was performed. A total of 517 strains were phage-typed according to the schemes of Lalko [27] and Ward et al. [21]. Strains were isolated from food-poisoning outbreaks and other common sources in Poland, between 1986–1995. Above 99% of all strains tested were differentiated to the definitive phage type using the Lalko collection of typing phages. Phage types 1 and 7 (PTs 1, 7) were the most isolated. The typing phages of Ward enabled to assign 56.5% of all strains (a total of 14 phage types were presented), 37.1% – reacted with phages without showing any of the designated phage types and 6.4% were untypable. Phage type 8 (PT8) predominated. The majority of Salmonella enteritidis strains from one phage type outbreaks of Lalko presented different types of lytic reactions with the Ward phages. Only the correspondence of Salmonella enteritidis PT7 of Lalko with PT8 of Ward et al. [21] was observed.     

Genomic diversity within phage types of Salmonella enterica ssp. enterica serotypes Enteritidis and Typhimurium

The diversity among 1354 strains of Salmonella enterica subsp. enterica, serotype Enteritidis (n = 847) and Typhimurium (n = 507) isolated in Finland in 1991-2002 (n = 608) and in 2003 (n = 746) were studied. The former strains were studied retrospectively by phage typing and pulsed-field gel electrophoresis (PFGE) harmonized in the European Salm-gene project. The latter strains were studied prospectively, and the results correlated to their antimicrobial susceptibility and association with travel to popular tourist destinations. During both periods, S. Enteritidis phage types (PTs) PT1 and PT4, and S. Typhimurium definite types (DTs) DT1 and DT104 were the major phenotypes. SENTXB.0001 was the dominating single PFGE type among S. Enteritidis strains (40% in 1991-2002; 57% in 2003), and accounted correspondingly for 23% and 63% of the PT1 strains, and 81% and 88% of the PT4 strains. No PFGE types dominated among the S. Typhimurium strains but a correlation was found between certain phage and PFGE types: among DT1 strains, STYMXB.0098 accounted for 66% (1991-2002) and 98% (2003) and among the DT104 strains STYMXB.0001 accounted for 84% and 97% in the two time periods, respectively. Of the S. Enteritidis strains isolated in 2003, 91% were associated with travel, most commonly to Spain, Greece, and Bulgaria. SENTXB.0001 was the major Salmonella PFGE type in these countries. In contrast, most (55%) S. Typhimurium strains were of domestic origin. While only 1.3% of the S. Enteritidis strains were multiresistant and 24% were resistant to nalidixic acid only, 30% of the S. Typhimurium strains were multiresistant. Among the multiresistant S. Typhimurium strains, R-type ACSSuT and PFGE type STYMXB.0001 of the DT104 complex dominated.     

Subtyping of Escherichia coli O157:H7 strains isolated from human infections and healthy cattle in Argentina

Shiga toxin-producing Escherichia coli (STEC) cause nonbloody (NBD) and bloody diarrhea (BD), and hemolytic uremic syndrome (HUS). Cattle have been described as their main reservoir. STEC O157:H7 is recognized as the predominant serotype in clinical infections, but much less is known about the dominant subtypes in humans and animals or their genetic relatedness. The aims of this study were to compare the STEC O157 subtypes found in sporadic human infections with those in the bovine reservoir using stx-genotyping, phage typing, and XbaI-pulsed-field gel electrophoresis (PFGE), and correlate the subtypes with the severity of clinical manifestations. The 280 STEC O157:H7 strains collected included in this study were isolated from HUS (n=122), BD (n=69), and NBD (n=30) cases, and healthy carriers (n=5), and from bovines (n=54) in the abattoirs. The stx-genotyping showed that stx?/stx(2c(vh-a)) was predominant in human (76.1%) and in bovine strains (55.5%), whereas the second more important genotype was stx? (20.8%) in human and stx(2c(vh-a)) (16.7%) in cattle strains. In human strains, PT4 (37.6%), PT49 (24.3%), and PT2 (18.6%) were the most frequent PTs (80.5%). In bovine isolates, PT2 (26%), PT39 (16.7%), and PT4 and PT49 (11.1% each) were predominant. By XbaI-PFGE, all 280 strains yielded 148 patterns with 75% similarity, and 169 strains were grouped in 37 clusters. Identical PT-PFGE-stx profile combinations were detected in strains of both origins: PT4-AREXH01.0011-stx?/stx(2c(vh-a)) (12 humans and one bovine), PT4-AREXH01.0543-stx?/stx(2c(vh-a)) (one human and four bovines), PT2-AREXH01.0076-stx?/stx(2c(vh-a)) (one human and four bovines), PT49-AREXH01.0175-stx?/stx(2c(vh-a)) (seven humans and one bovine), and PT49-AREXH01.0022-stx?/stx(2c(vh-a)) (seven humans and one bovine). No correlation was found among the stx-genotypes, the phage type, and the clinical symptoms.     

Efficacy and safety of low-dose intravenous versus intramuscular vitamin K in parenteral nutrition patients

Efficacy and safety of intravenous and intramuscular vitamin K were compared prospectively in patients receiving total parenteral nutrition. Sixty patients randomly received either a 1-mg daily iv injection (iv group) or a 10-mg weekly injection group (im group). Efficacy was determined by the prolongation of twice-weekly prothrombin (PT) and activated partial thromboplastin (APTT) times. The prolongation of both was not significantly different between the im and iv groups. The percent of PTs outside the normal range was not different for the two groups, although the iv group had more APTT values outside the range than did the im group (p = 0.002). The number of adverse reactions reported in the iv (5) and im (4) groups was also similar. Reactions were minor, not reproducible, and all patients recovered without sequelae. PT results from the iv and im groups were combined and compared to values from 28 patients in an earlier study who did not receive vitamin K. PTs in the no-vitamin K group were significantly prolonged over the vitamin K group (p = 0.0004). The results confirm that regular addition of vitamin K to TPN regimens decreases the incidence of elevated PTs. When administered appropriately, iv and im administration of vitamin K appear to be equally safe and effective in maintaining normal PTs and APTTs.     

Simultaneous infection with three different S. enteritidis strains in a nursing home resident

A culture taken from a nursing home resident as part of a S. enteritidis outbreak was found to have a mixed infection due to three different strains of S. enteritidis. One of the three strains belonged to phage type (PT) 4, one to PT6 and one reacted with phages but did not conform to any typing scheme (RDNC). All three strains had the 38.9 megadaltons (MDa) plasmid found in the isolates from the outbreak-related cases, in addition the PT6 and RDNC strains harboured a 69.9 MDa plasmid. The importance of phage typing and plasmid analysis for S. enteritidis strain characterization and their epidemiologic and bacterial significance are discussed.     

Work participation of patients with musculoskeletal disorders: is this addressed in physical therapy practice?

Background

Musculoskeletal disorders are the main complaints for visiting a physical therapist (PT) in primary health care; they have a negative effect on an individual’s quality of life and result in a major cost to society. Qualitative research has shown that physical therapists (PTs) treating patients with these disorders experience barriers in the integration of occupational factors within their practice, and also revealed a lack of cooperation between PTs and (other) occupational healthcare providers. The aim of this study is to quantitatively investigate how generalist PTs in the Netherlands, who treat patients with musculoskeletal disorders, currently integrate occupational factors within their practice, and to identify their opinions and needs with regard to enhancing the integration of the patient’s work within physical therapy practice.

Methods

A cross-sectional survey was conducted among generalist PTs who treat working-age (18–67 years) patients with musculoskeletal disorders. Generalist PTs were contacted for participation via digital news-mails and asked to fill out an online survey which was developed based on the results of a recent qualitative study. The survey consisted of: i) demographics of the participants, ii) questions on how generalist PTs currently integrate occupational factors within their practice, and iii) asked their opinion about the integration of occupational factors within physical therapy. The PTs were also asked about their needs with regard to the integration of occupational factors and with regard to cooperation with other (occupational) health professionals. All answers (using Likert scales) are presented as the number and percentage of the respondents reporting those specific answers, whereas all other answers are presented as means and standard deviations.

Results

Of the 142 respondents, 64% indicated that occupational factors should be addressed to a greater extent within physical therapy. To have the possibility to bill for a workplace assessment (60.6%) and more knowledge about laws and regulations (50%) were identified as needs of the respondents. Only 14.8% of the respondents indicated that they communicate with or consult a PT specialized in occupational health. Only 12.7% of the participants who do not have a specialized PT within their practice sometimes/regularly refer patients to a specialized PT.

Conclusions

Although generalist PTs address occupational factors within their practice, there is room for improvement. This study also identified a lack of cooperation between generalist PTs and PTs specialized in occupational health.

     

Concentrations of Organotin Compounds in Tissues and Organs of Dugongs from Thai Coastal Waters

Concentrations of butyltin (BT) and phenyltin (PT) compounds were measured in organs and tissues of dugongs (Dugong dugon) from the coastal waters of Thailand. Concentrations of BTs and PTs were in the range of 14–14,468 and <1–30 μg kg⁻¹ (detection frequency: 79%), respectively. Although concentrations of BTs in dugongs were higher then reported concentrations in cetaceans and pinnipeds, PTs were lower in dugongs. In half of the dugongs in which measurements were made, the concentration of BTs in the liver was the highest among the all the tissues and organs tested. Dibutyltin (DBT) or monobutyltin (MBT) was found to be the dominant compounds among the BTs. The distribution in the body of PTs was not clear because of the lower levels of this compound. TPT was the dominant compound among PTs. The coastal area of Thailand is located off the Gulf of Thailand and the Andaman Sea. Concentrations of organotin (OT) compounds in dugongs collected from the Gulf of Thailand were compared to those from the Andaman Sea. No significant differences in BT or PT concentrations were observed between the two areas (p < 0.05). The concentrations of BTs and PTs in the livers of dugongs were decreased between 1998 and 2002, suggesting a decrease in OT concentrations in the surrounding environment.     

Does knowledge of a patient's workers' compensation status influence clinical judgments?

It is generally acknowledged that compensation payments (WCB) influence rehabilitation outcome in a negative manner. Patients receiving WCB have more treatment over a longer time period than their non compensated (NWCB) cohorts. It is not clear whether therapists (PT) perceive WCB clients as being more impaired and expect them to have a worse outcome than clients without WCB. The purpose of this study was to determine whether PTs' clinical judgments are influenced by the knowledge of a patients WCB status and whether this knowledge influences their assessment findings or prognostic judgments. A convenience sample of 69 physical therapists (PTs) participated. Each PT viewed three videotaped assessments, of patients with low back pain (LBP) that differed in severity. The PT was provided with a brief history of the patient. Included in the history was a statement that the patient was (WCB group), or was not (NWCB group) in receipt of workers compensation benefits (WCB). The third group of PTs was given no information (control group) about the patient. PTs recorded physical assessment findings and made prognostic judgments about the patients. Data for the physical assessment findings and prognoses recorded by the PTs was analyzed across information groups using ANOVA. Knowledge of compensation status did not influence the PTs' physical assessment findings but did influence prognostic judgments. WCB status was deemed to have a negative effect on outcome in patients with mild LBP. Additionally, NWCB status was deemed to have a positive influence on outcome in patients with severe LBP. The differences were most marked in the short term (1 month). It was concluded that PTs expectations of outcome are influenced by prior knowledge of compensation status.     

Salmonella enteritidis phage types in Germany

In order to monitor the epidemiological situation ofS. enteritidis in Germany, in 1990–91 1138 isolates from more than 180 locations in West Germany were phage typed. 1124 strains (98.8%) from all sources were typeable, belonging to 21 different phage types (PT). PT4 strains were isolated most frequently (70.8%). In addition, PT7, 25, 34 and 8 were of epidemiological relevance with incidences of 7.2 to 4.5%. The comparison of data shows that in Germany, like in other parts of Europe, PT4 predominates. This phage type is, however, infrequent in North America, where PT8 has the highest incidence.     

Antimicrobial susceptibility and phage types of Salmonella enteritidis strains isolated in the Lublin area

The study aimed at specifying the value of two traditional methods of typing, using the collection of 241 strains of Salmonella Enteritidis isolated from people and animals in the Lublin area in 1994-1995 from the occasional cases of infections. There were 8 phage types identified among the examined strains. Phage types PT 6 (40.24% of strains) and PT 7 (29.46%) were the most numerous ones. Salmonella Enteritidis was numbered among 38 profiles on the basis of the analysis of resistance to 15 antimicrobial agents. It was found that nitrofurantoin had the lowest efficacy in vitro in relation to the examined collection of Salmonella isolates. High percentage of strains were characterized by lack of susceptibility to streptomycin, neomycin, cefixime, tetracycline and canamycine. While analyzing the profiles of resistance to chemiotherapeutics and the expression of phage type of the examined strains it was observed that only 14.1% of all strains showing resistance to nitrofurantoin represented at the same time phage type PT 6, whereas 10.8% of strains belonging to the same resistance profile indicated PT 7 phage type. In correlated analysis of resistance to chemiotherapeutics and phage type expression of the examined collection of 241 isolates of Salmonella Enteritidis, 18.3% of strains showed distinct and unique set of these two features, which can be used in epidemiological investigations for the preliminary characterization of the bacterial population.     

Clonal dissemination of Salmonella enterica serovar Infantis in Germany

Salmonella enterica serovar Infantis (Salmonella Infantis) is consistently isolated from broiler chickens, pigs, and humans worldwide. This study investigated 93 epidemiologically unrelated Salmonella Infantis strains isolated in Germany between 2005 and 2008 in respect to their transmission along the food chain. Various phenotypic and genotypic methods were applied, and the pathogenicity and resistance gene repertoire was determined. Phenotypically, 66% of the strains were susceptible to all 17 antimicrobials tested, while the others were almost all multidrug-resistant (two or more antimicrobial resistances), with different resistance profiles and preferentially isolated from broiler chickens. A number of phage types (PTs) were shared by strains from pigs, broiler chickens, and humans (predominated by PT 29). One, PT 1, was only detected in strains from pigs/pork and humans. Pulsed-field gel electrophoresis (PFGE) subdivided strains in seven different clusters, named A-G, consisting of 35 various XbaI profiles with coefficient of similarity values of 0.73-0.97. The majority of XbaI profiles were assigned to clusters A and C, and two predominant XbaI profiles were common in strains isolated from all sources investigated. Multi-locus sequence typing (MLST) analysis of selected strains representing the seven PFGE clusters revealed that they all belonged to ST32. The pathogenicity gene repertoire of 37 representative Salmonella Infantis strains analyzed by microarray was also identical. The resistance gene repertoire correlated perfectly with the phenotypic antimicrobial resistance profiles, and multidrug-resistant strains were associated with class 1 integrons. Overall, this study showed that two major closely related genotypes of Salmonella Infantis can transmit in Germany to humans through contaminated broiler meat or pork, and consequently presents a hazard for human health.