Biomedical subjects

P Janssen

Publications and source records attributed to P Janssen.

At least 37 records · Page 2Linked to original sources

PubMed1999

Vaginal sonography and gender preference for sonographer.

PURPOSE: The invasive nature of vaginal sonography, recently introduced as an improved diagnostic method for imaging the contents of the pregnant uterus, has provoked discussion about patient preference for female sonographers. This study examined whether patients had a gender preference for the sonographer who would conduct such an examination. METHODS: Over 3 months, a written survey was given to pregnant women to complete anonymously while waiting for their scheduled sonographic examination. The survey covered gender preference for the sonographer and education, ethnicity, and previous experience with the procedure. Surveys were turned in by 1,002 pregnant women. RESULTS: Of the women whose survey responses were analyzed, 62% preferred a female sonographer. The principal reason given for this preference was comfort with the same gender. The majority of respondents were 25-40 years old, married, white, and multiparous. The level of education varied widely. CONCLUSIONS: These findings point to a need to seek consumer input when new technology is introduced, to provide women with choices where possible, and to ensure that they have access to information about those choices.

Educational Status↗

PubMed1999

Amplified-fragment length polymorphism analysis versus macro-restriction fragment analysis for molecular typing of Streptococcus pneumoniae isolates.

Forty-eight pneumococci were genotyped by on-line laser fluorescence amplified-fragment length polymorphism (AFLP) and pulsed-field gel electrophoresis (PFGE) analysis of chromosomal restriction fragments. Overall, the data generated by the two methods corresponded well. However, with AFLP, clusters were delineated at a higher similarity level, and isolate differentiation was more pronounced. AFLP and PFGE were equally efficient for assessing intraserotype diversity. We conclude that AFLP is a useful alternative to PFGE.

Algorithms↗

PubMed1999

Conservative management of spontaneous abortions. Women's experiences.

OBJECTIVE: To describe women's experiences with expectant management of spontaneous abortions. DESIGN: Descriptive survey using questionnaires with fixed-choice and open-ended questions. The latter were analyzed for themes, using qualitative methods. SETTING: Urban and suburban private primary care family practices. PARTICIPANTS: A convenience sample of family practice patients (59 of 80 eligible) pregnant for less than 12 weeks who had spontaneous abortions without surgery. Response rate was 84.7%; 50 questionnaires were received from the 59 women. METHOD: Women were asked about their physical experiences, including amount of pain and bleeding; emotional effects; their satisfaction with medical care; and their suggestions for improving care. MAIN FINDINGS: The mean worst pain experienced during a spontaneous abortion on an 11-point scale was 5.9. Bleeding varied, but was often very heavy. Satisfaction rate was 92.9% with family physician care and 84.6% with hospital care. Women described the emotional effect of "natural" spontaneous abortions and made recommendations for improving care. CONCLUSIONS: A better understanding of the physical and emotional experiences of the women in this study might help physicians better prepare and support patients coping with expectant management of spontaneous abortions.

Abortion, Spontaneous↗

PubMed1999

Reducing surgery in management of spontaneous abortions. Family physicians can make a difference.

OBJECTIVE: To test the effectiveness of physician and patient education in reducing the rate of surgery in management of spontaneous abortions in family practice. DESIGN: A before-after intervention trial. SETTING: Urban and suburban family doctors' practices in greater Vancouver, BC. PARTICIPANTS: Family practice patients (56 physicians contributed 417 patients) who had spontaneous abortions between June 1997 and August 1998. INTERVENTIONS: Seminars for doctors and educational pamphlets for patients. MAIN OUTCOME MEASURES: Rate of surgeries, and rates of referrals and complications. RESULTS: In the 2 years before the intervention, the rate of surgery was 45.8% (n = 299); after, it was 32.2% (n = 118). No transfusions were required. Before the intervention, 17% of women had hemorrhages; after, 13%. Rates of infection were 3.7% and 0.8%, respectively. Rates of referral to gynecologists were 54.0% and 40.2%, respectively. CONCLUSIONS: Patients of family doctors who attended seminars and agreed to join the study had significantly reduced rates of surgery after spontaneous abortions. Rates of referral for these patients were also lower, and there was no increase in complications.

Abortion, Spontaneous↗

PubMed1998

Scarcity or complete lack of single rhamnose residues interspersed within the homogalacturonan regions of citrus pectin.

Commercial citrus pectin containing galacturonic acid and rhamnose in a ratio of approximately 40:1 was saponified and then exhaustively digested with endopolygalacturonase (EPG). The products were separated by ultrafiltration into low-molecular-weight (LMW) and high-molecular-weight (HMW) fractions. The LMW fraction accounted for 80% of the starting material, but for only 10% of the total rhamnose. The molar ratio of galacturonic acid to rhamnose of the LMW fraction was 236, suggesting that very few small Rha-containing oligomers were generated by the EPG digestion. No distinct Rha-containing oligomers were found by various chromatographic analyses of the LMW fraction. The HMW fraction, which only accounted for 10% by weight of the starting pectin, contained more than 85% of the rhamnose. The ratio of GalA to Rha in the HMW fraction was 1.7:1 and partial acid hydrolysis of this fraction produced a series of oligomers consisting of GalA-Rha repeating units, suggesting that it contained rhamnogalacturonan, which has a backbone composed of GalA-Rha disaccharide repeating units. The HMW fraction also contained large amounts of arabinose and galactose, which probably originated from side chains linked to some of the rhamnose residues. We propose that commercial citrus pectin is composed of two regions: the predominant region consists of chains of uninterrupted 1,4-linked alpha-D-GalA residues with between 60-70% of the residues methyl esterified; and the other region consists of rhamnogalacturonan with a backbone composed of GalA-Rha disaccharide repeating units and neutral sugar side chains.

Carbohydrate Sequence↗

PubMed1998

AFLP typing of Staphylococcus epidermidis in multiple sequential blood cultures.

AFLP is a novel high-resolution PCR-based DNA fingerprinting method generating complex banding patterns that can be used for comparative analysis. In the present study, the applicability of AFLP in fingerprinting Staphylococcus epidermidis isolates was investigated. The criteria considered were stability of patterns, reproducibility, discriminatory capacity and consistency with epidemiological context. Repeated testing of strains and investigation of subcultures showed that AFLP patterns were reproducible and stable with an intrastrain similarity of S > or = 94% as determined by analysis of digitized patterns. Fifteen unrelated strains were heterogeneous, with a level ranging from 78-93%. The applicability of AFLP in epidemiological studies of S. epidermidis was tested on 11 sets of four blood isolates each, from 11 patients with suspected septicaemia. Nine sets had indistinguishable or highly similar AFLP patterns for each isolate per set, while two sets had heterogeneous patterns. These results show that AFLP has high discriminatory power for strain identification in S. epidermidis.

Bacteremia↗

PubMed1998

Communicative styles of mothers interacting with their preschool-age children: a factor analytic study.

The aim of this study was to determine if mothers display identifiably different communicative styles in their interaction with their normally developing two- to five-year-old children. In order to investigate this issue an extensive coding system was developed, which assessed the structural organization and the communicative function of the speech of 71 mothers as they interacted with their children. By means of factor analysis three maternal communicative styles were distinguished: non-intervening, explaining and directing. In the non-intervening style there is no direct pressure from the mother on the child to respond verbally. The explaining mother is primarily concerned with providing information to her child in a way that gives the child little opportunity to take the speaking turn. The directing mother is mainly engaged in directing the child's behaviour by means of verbal control. The internal consistency of the three communicative styles appeared to be both satisfactory and related to relevant child and mother features.

Child, Preschool↗

PubMed1998

Management of spontaneous abortion in family practices and hospitals.

BACKGROUND AND OBJECTIVES: We performed two retrospective chart surveys, the first of 200 consecutive hospital emergency visits for spontaneous abortion and the second in 33 family physicians' offices examining 245 patients with spontaneous abortions. This study determined the rate of surgical management of spontaneous abortions within family practices and hospitals, as well as the rate of referrals and complications. METHODS: In the retrospective chart surveys, the information collected included the number of spontaneous abortions, dilation and curettages (D&Cs), referrals, and complications. RESULTS: Of the women presenting to the hospitals, 92.5% had D&Cs, while 51% of the women presenting to family physicians had D&Cs. Of the women presenting to the hospitals, 99.5% were referred to gynecologists, compared with 41% of the family practice patients. Hemorrhage occurred in 4.6% of the hospital patients and 2% of the family practice patients. Infection occurred in 6% of the hospital patients and .8% of the family practice patients. CONCLUSIONS: Patients with spontaneous abortions who saw their family physicians were more likely to be managed conservatively than those seen in the hospitals. There was no increase in complications in the conservatively managed patients.

Abortion, Spontaneous↗

PubMed1997

Inclusion of Aeromonas DNA hybridization group 11 in Aeromonas encheleia and extended descriptions of the species Aeromonas eucrenophila and A. encheleia.

The recently reported chemotaxonomic and genotypic description of two well-separated subgroups (I and II) in Aeromonas eucrenophila and their affiliation to Aeromonas encheleia and the unnamed Aeromonas DNA hybridization group (HG) 11 (G. Huys, M. Altwegg, M.-L. Hänninen, M. Vancanneyt, L. Vauterin, R. Coopman, U. Torck, J. Lüthy-Hottenstein, P. Janssen, and K. Kersters, Syst. Appl. Microbiol. 19:616-623, 1996) has questioned the original species descriptions of A. eucrenophila and A. encheleia. In order to elucidate the unclear taxonomic status of these taxa in the genus Aeromonas, we have further investigated a collection of 14 reference strains and 14 related isolates encompassing the taxa A. eucrenophila subgroups I and II, A. encheleia, and HG11 by DNA-DNA hybridization (on 17 of the 28 strains) and phenotypic characterization (on all 28 strains). Genotypically, the investigated strains could be grouped into two DNA hybridization groups that exhibited between-group homologies ranging from 42 to 52%. The members of DNA homology group I (DNA binding, 76 to 100%) were strains of A. eucrenophila subgroup I, including the type strain LMG 3774, and two A. eucrenophila-like isolates, leading to the conclusion that these strains should be considered true representatives of the species A. eucrenophila. The strains of A. eucrenophila subgroup II, HG11, and A. encheleia, on the other hand, were closely joined in DNA homology group II (DNA binding, 74 to 105%) together with two presumptive A. encheleia isolates. The fact that strain LMG 16330T of A. encheleia was the only type strain residing in DNA homology group II implies that HG11 and A. eucrenophila subgroup II should be classified in the species A. encheleia. Except for the somewhat aberrant phenotypic positions of HG11 strains LMG 13075 and LMG 13076, the establishment of DNA homology groups I and II was supported by the delineation of phena 1 and 2 (level of correlation, 90%), respectively, as revealed by numerical analysis of 136 phenotypic test results. These data indicate that A. eucrenophila and A. encheleia are phenotypically highly related but can be easily separated by testing the production of acid from D-cellobiose and lactose and the assimilation of D-cellobiose. Extended descriptions of both species are given.

Aeromonas↗

PubMed1997

Aeromonas popoffii sp. nov., a mesophilic bacterium isolated from drinking water production plants and reservoirs.

We examined the taxonomic position of seven Aeromonas isolates, recovered from Flemish and Scottish drinking water production plants and reservoirs, which were previously recognized by numerical analysis of genomic AFLP fingerprints as members of an unknown Aeromonas taxon that most closely resembled the species Aeromonas bestiarum (DNA hybridization group [HG] 2). The new phenotypic and DNA-DNA hybridization data obtained in this study show that the A. bestiarum-like strains constitute a separate Aeromonas species, for which the name Aeromonas popoffii sp. nov. is being proposed. The new species exhibited an internal DNA relatedness ranging from 79 to 100% and was 22 to 63% related to the type or reference strains of other Aeromonas spp. The highest DNA binding values were determined with A. bestiarum (51 to 63%), followed by Aeromonas hydrophila sensu stricto (HG1; 50 to 60%) and Aeromonas salmonicida (HG3; 39 to 55%). Although fingerprints generated by ribotyping and cellular fatty acid analysis often were highly similar, minor differences between the respective fingerprints were of significance for the differentiation of A. popoffii from its closest taxonomic neighbors, HG1, HG2, and HG3. Phenotypically, all seven strains of A. popoffii were positive for acid and gas production from D-glucose and glycerol, growth in KCN broth, arginine dihydrolase, DNase, Voges-Proskauer reaction, and resistance to vibriostatic agent O/129 and ampicillin but displayed negative reactions for production of urease, tryptophan deaminase, ornithine decarboxylase, and lysine decarboxylase (LDC). None of the strains displayed strong hemolytic activity. The lack of D-sucrose fermentation and LDC production and the ability to utilize DL-lactate as the sole energy and carbon source were useful characteristics for the biochemical separation of A. popoffii from A. bestiarum. Other Aeromonas spp. could be differentiated phenotypically from the new species by at least two features. The chromosomal G+C content of A. popoffii ranges from 57.7 to 59.6 mol%. Strain LMG 17541 is proposed as the type strain.

Aeromonas↗

PubMed1997

Discrimination of Acinetobacter genomic species by AFLP fingerprinting.

AFLP is a novel genomic fingerprinting method based on the selective PCR amplification of restriction fragments. The usability of this method for the differentiation of genomic species in the genus Acinetobacter was investigated. A total of 151 classified strains (representing 18 genomic species, including type, reference, and field strains) and 8 unclassified strains were analyzed. By using a single set of restriction enzymes (HindIII and TaqI) and one particular set of selective PCR primers, all strains could be allocated to the correct genomic species and all groups were properly separated, with minimal intraspecific similarity levels ranging from 29 to 74%. Strains belonging to genomic species 8 (Acinetobacter lwoffii sensu stricto) and 9 grouped together in one cluster. The closely related DNA groups 1 (Acinetobacter calcoaceticus), 2 (Acinetobacter baumannii), 3 and 13TU (sensu Tjernberg & Ursing 1989) were clearly distinguishable, with intraspecific linkage levels above 50%. Strains of the independently described genomic species 13BJ (sensu Bouvet & Jeanjean 1989) and 14TU linked together at a relatively low level (33%). Although a previous DNA-DNA hybridization study seemed to justify the unification of these genomic species, AFLP analysis actually divides the 13BJ-14TU group into three well-separated subgroups. Finally, four unclassified strains obtained from diverse sources and origins grouped convincingly together, with a similarity linkage level of approximately 50%. These strains showed no similarities in their AFLP patterns with any of the other 155 strains studied and may represent a thus-far-undescribed Acinetobacter species. Based on these results, AFLP should be regarded as an important auxiliary method for the delineation of genomic species. Furthermore, because AFLP provides a detailed insight into the infraspecific structure of Acinetobacter taxa, the method also represents a highly effective means for the confirmation of strain identity in the epidemiology of acinetobacters.

Acinetobacter↗

PubMed1997

Diversity, persistence, and virulence of Aeromonas strains isolated from drinking water distribution systems in Sweden.

The Aeromonas populations in 13 Swedish drinking water distribution systems, representing different treatments, were investigated. From each system, water samples were collected four times during the period from May to September 1994 from raw water and water after treatment and at two to five sites within the distribution system. In total, 220 water samples were collected. From samples containing presumptive Aeromonas, up to 32 colonies were analyzed by the PhenePlate Aeromonas (PhP-AE) system, which is a highly discriminating biochemical fingerprinting method. Selected isolates from different phenotypes (PhP types) were further identified by the API 20 NE system and by gas-liquid chromatography analysis of fatty acid methyl esters (FAMEs). Selected isolates were also assayed for their potential to produce hemolysin and cytotoxin and for their ability to adhere to human intestinal cells. In total, 117 water samples (53%) contained presumptive Aeromonas which numbered up to 10(6) CFU/100 ml in raw water and up to 750 CFU/100 ml in tap water. Among the 2,117 isolates that were subjected to typing by the PhP-AE system, more than 300 distinct PhP types were found, of which the majority occurred only sporadically. Raw (surface) water samples usually contained many different PhP types, showing high diversity indices (Di) (median Di = 0.95). The Aeromonas populations in samples collected from within the distribution systems were less diverse (median Di = 0.58) and were often dominated by one major PhP type that was found on several sampling occasions. Seventeen such major PhP types could be found and were represented in 1,037 isolates (49%). Identification by API 20 NE and FAME analysis revealed that most of the major PhP types were Aeromonas hydrophila or belonged to unidentified Aeromonas species. Hemolysin and cytotoxin production was observed in most major PhP types (representing 87 and 54% of the assayed isolates, respectively), and adherence was found in 89% of the isolates that produced cytotoxin. Thus, the data presented here show that although raw water may contain very diverse Aeromonas populations, the populations seemed to be remarkably stable within the studied water distribution systems, and that some potentially pathogenic Aeromonas strains could persist for several months in drinking water.

Aeromonas↗

PubMed1997

Characterization of Aeromonas spp. isolated from humans with diarrhea, from healthy controls, and from surface water in Bangladesh.

Aeromonas isolates from patients with diarrhea in Bangladesh (n = 69), from healthy controls (n = 11), and from surface water (n = 40) were analyzed with respect to their hybridization groups (HGs) by the aid of fatty acid methyl ester (FAME) characterization and DNA fingerprinting by AFLP, biochemical phenotypes (Phe-nePlate [PhP] types), and the production of hemolysin and cytotoxin. The aim of the investigation was to find out whether certain strains carrying virulence factors predominated among patient isolates. According to FAME and/or AFLP analysis, most human isolates were allocated to DNA HGs 4 (Aeromonas caviae) and 1 (A. hydrophila). Most environmental strains were allocated to HG8 (A. veronii biogroup sobria) and HG4 (A. caviae), and only one was of HG1. According to PhP typing, the diversity among patient isolates was lower than that among other strains, and two dominating PhP types (types BD-1 and BD-2) were identified in 29 and 30% of the patient isolates, respectively. PhP type BD-1 was also common among the environmental isolates, whereas PhP type BD-2 was only identified in two of the other isolates. Twenty-five of 26 isolates belonging to HG1 were of the same PhP type (BD-2), whereas isolates of other common HGs were more diverse according to their PhP types. Hemolytic and cytotoxin-producing strains occurred more frequently among the environmental isolates than among patient isolates. However, the hemolytic and cytotoxic activities among human isolates was strongly correlated to the HG1/BD-2 type, which, in addition, showed high cytotoxin titers (median values, 1/512 compared to 1/128 for cytotoxin-positive isolates belonging to other types). Thus, the HG1/BD-2 type may represent a pathogenic A. hydrophila type that is able to produce diarrhea in humans.

Aeromonas↗

PubMed1997

A 4-year study of the diversity and persistence of coliforms and Aeromonas in the water of a Swedish drinking water well.

Coliforms and Aeromonas, isolated over a sampling period of 4 years from a Swedish drinking water well, were analysed for their phenotypical diversity and for their ability to persist in the well water. From each of the 40 water samples collected from the well, 32 bacterial isolates were subjected to typing by the PhenePlate (PhP) biochemical fingerprinting system. Strains able to persist in the well water were further characterized using the API 20E system, gas-liquid chromatographic cellular fatty acid analysis, and the DNA fingerprinting technique AFLP. Using the PhP system, a total of 170 different phenotypes were identified among 1143 studied isolates. Most phenotypes were only represented by a few isolates and (or) were restricted to one or two sampling occasions. However, one particular phenotype (RV-C01), identified as Aeromonas hydrophila using the API 20E system and fatty acid analysis, reoccurred in 28 samples distributed over the whole study period and often dominated the bacterial population in the well water. AFLP analysis revealed that the RV-C01 isolates displayed basically identical fingerprints. Our results thus suggest that a genetically stable Aeromonas clone resided in the well water over the whole 4-year study, whereas other bacterial strains studied were only transient inhabitants of the well.

Aeromonas↗

PubMed1997

How can second-stage management prevent perineal trauma? Critical review.

OBJECTIVE: To learn which factors influencing perineal integrity were modifiable by physicians and pregnant women. DATA SOURCES: Medical, nursing, and midwifery literature was searched mainly for randomized controlled trials. STUDY SELECTION: We chose articles on perineal trauma pattern, sexual dysfunction or satisfaction, urinary incontinence, and pelvic floor function. We identified 80 papers and studied 16 in detail. SYNTHESIS: Five factors affected perineal integrity: episiotomy, third-trimester perineal massage, mother's position in second-stage labour, method of pushing, and administration of epidural analgesia. Episiotomy does not improve perineal outcomes when used routinely. Third-trimester perineal massage was discussed only in inadequate studies. Studies comparing position in birth chairs and recumbent versus upright positions were inadequate for making firm recommendations. Studies of methods of pushing and use of epidural analgesia were limited and uncontrolled; no recommendations were possible. CONCLUSION: Only limiting episiotomy can be strongly recommended. In the absence of strong data to the contrary, women should be encouraged to engage in perineal massage if they wish and to adopt the birth positions of their choice. Caretakers should be aware of the possibility of interfering with placental function when women hold their breath for a long time when pushing.

Delivery, Obstetric↗

PubMed1996

High resolution DNA fingerprinting of Acinetobacter outbreak strains.

AFLP is a novel high resolution fingerprinting method that can be used to delineate intraspecific relationships among a large variety of organisms, including bacteria. In the present study, this method was tested for its usefulness in the epidemiological typing of Acinetobacter strains. A total of 25 Acinetobacter strains originating from five hospital outbreaks in three countries were used. Isolates from the same outbreak displayed identical banding patterns and each set of outbreak strains could be found in one particular AFLP cluster. These data are in good agreement with the results obtained by other typing methods previously used on the same set of strains, indicating that AFLP analysis may be a valuable alternative in epidemiological typing.

Acinetobacter↗

PubMed1996

[Granulomatous hepatitis attributed to the combination pyrimethamine-chloroquine].

After her holiday in South Africa, a 50-year-old woman was admitted because of fever and pain in the upper abdomen. The laboratory tests showed moderately increased serum liver enzyme activities. The liver biopsy showed a granulomatous hepatitis. Further investigations revealed no evidence for sarcoidosis, tuberculosis or infectious hepatitis, nor for other granulomatous diseases or infectious diseases relevant to South Africa. Upon discontinuation of the malaria prophylaxis with Daraclor (pyrimethamine and chloroquine (sulphate)) the symptoms disappeared and the liver function tests returned to normal. It was concluded that Daraclor was the probable cause of granulomatous hepatitis in this patient. This adverse effect was not published before.

Antimalarials↗

PubMed1996

The Blom-Singer tracheostoma valve as a valuable addition in the rehabilitation of the laryngectomized patient.

Prosthesis-assisted tracheo-esophageal speech has proven its value in post-laryngectomy voice rehabilitation, although manual occlusion of the tracheostoma during speech is necessary. In contrast a tracheostoma valve enables hands-free speech. We have now had experience with 30 patients using the Blom-Singer tracheostoma valve for more than 6 months and have found that most patients prefer prosthesis-assisted speech with the tracheostoma valve. Measurement of several speech parameters with digital and valve occlusion of the tracheostoma did not show any significant differences between the two speaking conditions. Problems included maintenance of an airtight seal, outward forcing of the valve diaphragm during forced expiration and subjective increased airflow resistance.

Adult↗