Biomedical subjects

J L Larsen

Publications and source records attributed to J L Larsen.

At least 55 records · Page 3Linked to original sources

PubMed1997

Typing of the fish pathogen Listonella (Vibrio) anguillara by pyrolysis mass spectrometry.

Twenty-eight representatives of Listonella (Vibrio) anguillara serovars O1, O2 and O3 were compared by Curie-point pyrolysis mass spectrometry (PyMS). The representatives of serovars O1 and O3 formed discrete, homogeneous groups in ordination plots of the PyMS data. Strains from serovar O2 were recovered in two groups, one of which encompassed six strains including the type strain of the species and the reference strain for serovar O2, and the other included two strains which showed cross-reactions between serovars O2 and O5. The almost complete agreement found between the PyMS and the serological data suggests that pyrolysis mass spectrometry will prove to be an effective method for interstrain comparison within the species Listonella anguillara.

Animals↗

PubMed1997

Phenotypic and genotypic characterization of Vibrio vulnificus: proposal for the substitution of the subspecific taxon biotype for serovar.

The classification of Vibrio vulnificus strains into two biotypes has been maintained on the basis of phenotypic properties and eel virulence. Biotype 2 is virulent for eels, negative for the indole reaction, and serologically homogeneous (serogroup E), whereas strains of biotype 1 are avirulent, indole positive, and serologically heterogeneous. In the present study, we phenotypically and genotypically characterized 21 V. vulnificus isolates, recovered mainly from northern Europe, by comparing them with reference strains of both biotypes to look for new isolates of biotype 2. The results of this work revealed that the majority of isolates virulent for eels presented phenotypic traits previously considered characteristics of biotype 2 and specific ribotypes with HindIII. However, among the new isolates we found (i) a serogroup E strain virulent for eels but indole positive and (ii) one isolate not belonging to serogroup E but pathogenic for eels. Since no biochemical test for specific serogroup can with certainty be associated with eel virulence, we propose to classify V. vulnificus strains into serovars instead of biotypes. Thus, we suggest serovar E as the denomination of those strains previously classified as biotype 2. Finally, the occurrence of serogroup E in eels cultured in Norway and Sweden, as well as from human infections and shrimp, has been demonstrated.

Bacterial Typing Techniques↗

PubMed1997

Comparison of ribotyping and randomly amplified polymorphic DNA PCR for characterization of Vibrio vulnificus.

A total of 85 isolates of Vibrio vulnificus were characterized by ribotyping with a probe complementary to 16S and 23S rRNA of Escherichia coli and by randomly amplified polymorphic DNA-PCR (RAPD-PCR) with a 10-mer oligonucleotide primer. The RAPD-PCR results were scanned, and the images were analyzed with a computer program. Ribotype membranes were evaluated visually. Both the ribotyping and the RAPD-PCR results showed that the collection of strains was genetically very heterogeneous. Ribotyping enabled us to differentiate U.S. and Danish strains and V. vulnificus biotypes 1 and 2, while the RAPD-PCR technique was not able to correlate isolates with sources or to differentiate the two biotypes, suggesting that ribotyping is useful for typing V. vulnificus strains whereas RAPD-PCR profiles may subdivide ribotypes. Two Danish clinical biotype 2 strains isolated from fishermen who contracted the infection cleaning eels belonged to the same ribotype as three eel strains (biotype 2), providing further evidence that V. vulnificus biotype 2 is an opportunistic pathogen for humans. One isolate (biotype 2) from Danish coastal waters also showed the same ribotype as the eel strains. This is, to our knowledge, the first time the isolation of V. vulnificus biotype 2 from coastal waters has been described.

Animals↗

PubMed1997

Vibrio damsela associated with diseased fish in Denmark.

A total of 26 Vibrio damsela strains were isolated in Denmark. Fifteen strains were isolated from the head kidney of rainbow trout (Oncorhynchus mykiss) in aquaculture, eight were from organs of two stingrays (Dasyatis pastinaca) held in captivity, two were from organs and pathological material of a nurse shark (Orectolobus ornatus) held in captivity, and one was from the water in the aquarium where the rays and shark were kept. This is the first report on the isolation of V. damsela in Denmark and the first report on this organism associated with diseased farmed rainbow trout. Ecological and epizootiological aspects of the observation are discussed on the basis of phenotypic and genotypic properties of the isolated strains.

Animals↗

PubMed1997

Solitary pancreas transplantation. Experience with 62 consecutive cases.

OBJECTIVE: To determine the safety and efficacy of solitary pancreas transplantation in the treatment of IDDM. RESEARCH DESIGN AND METHODS: A single-center retrospective case series of 62 consecutive solitary pancreas transplants (20 sequential pancreas after kidney, 42 pancreas transplants alone) performed in 57 adult IDDM patients was studied. Indications for solitary pancreas transplantation were 1) the presence of two or more overt diabetic complications and/or 2) glucose hyperlability with hypoglycemic unawareness and impaired quality of life. The recipient group consisted of 31 men and 26 women with a mean age of 38 years (range 25-62) and a mean duration of diabetes of 26 years (range 14-52). Mean pretransplant glycohemoglobin level was 9.9 +/- 2.6%. Organ acceptance was restricted to ideal donors and man-dated a minimum of a two-antigen match (mean human leukocyte antigen ABDR match 2.7). The mean cold ischemia time was 16.6 h. Whole-organ pancreas transplantation was performed with bladder drainage by the duodenal segment technique. All patients were managed with either triple or quadruple immunosuppression. Monitoring included prospective urine cytology as well as cystoscopic transduodenal needle biopsies. RESULTS: The mean length of initial hospital stay was 18 days, and mean hospital charges were $106,341. The incidences of rejection, infection, and surgical complications were 70, 55, and 47%, respectively. Overall patient and graft survival rates were 86 and 52%, respectively, with a mean follow-up of 28 months. All patients with functioning grafts had excellent metabolic control (mean glycohemoglobin level 5.1%) and achieved good rehabilitation. CONCLUSIONS: Despite morbidity, solitary pancreas transplantation can be performed with improving success, can enhance quality of life, and can offer an opportunity to arrest secondary diabetic complications.

Adult↗

PubMed1997

Vibrio anguillarum serogroup O3 and V. anguillarum-like serogroup O3 cross-reactive species--comparison and characterization.

Forty-five Vibrio anguillarum-like isolates reacting with V. anguillarum serogroup O3 antiserum were examined in 30 characters to clarify their phenotypical properties, while their genotype was examined by ribotyping. The strains were isolated from diseased and dead fish or from environmental sources such as water, sediment, plankton, and faeces and gills of healthy fish. Phenotypically, the similarity of all the strains was more than 90%. However, significant differences between the fish-associated and environmental strains were detected. Biochemically, deviations were found in the Voges-Proskauer test and lysine decarboxylase reaction. Clustering analysis of the ribotypes showed two distinct clusters with a similarity of only 32%. Two strains representing each of these groups were used in a LD50 study, which showed some difference also in the pathogenicity between environmental and fish strains. It is suggested that the environmental strains belong to another species than V. anguillarum, but serologically cross-reacting with the V. anguillarum serogroup O3. The ribotyping as well as biochemical results indicated that the environmental strains possibly belong to Vibrio aestuarianus. The bona fide V. anguillarum serogroup O3 strains proved to be very homogeneous both phenotypically and genotypically, and the similarity of ribotypes was more than 96%. The V. anguillarum-like, serogroup O3-reactive strains from the environment were more heterogeneous in their biochemical behaviour, and showed an approximately 70% similarity in ribotypes.

Antigens, Bacterial↗

PubMed1997

Vaccination strategies in freshwater salmonid aquaculture.

The focus of this chapter is antibacterial vaccines. The main salmonid species in freshwater aquaculture is the rainbow trout. Other salmonid species are produced on a limited scale. The most important bacterial fish diseases in European freshwater aquaculture are the rainbow trout fry syndrome-RTFS-(Flavobacterium psychrophilum) and enteric redmouth disease-ERM-(Yersinia ruckeri) which are widespread and cause serious epizootics, while furunculosis (Aeromonas salmonicida) is endemic, only giving overt disease under extremely stressing conditions. In the hatchery, there is a need for vaccination against RTFS (not commercially available) and ERM; in the ponds it is urgent to vaccinate against ERM, while the importance of furunculosis vaccination is not clear. The fish for ongrowing in saltwater should be vaccinated against ERM, furunculosis and vibriosis. Commercial vaccines are available against these diseases, either as single component or combination vaccines for immersion and injection-and oral vaccines are under registration. Hitherto, there has not been much strategic research on vaccination in freshwater; however recent results suggest that with the regime of vaccines available (and soon available), fish should be vaccinated with an ERM immersion vaccine in the hatchery approximately four weeks before transfer to the ponds. To cover the growth period in fresh water an oral booster should be given two to three months later. There is a need for development and research in strategic use of an RTFS and a furunculosis vaccine in freshwater aquaculture.

Aeromonas↗

PubMed1997

Cerebrospinal fluid protein concentrations in patients with sciatica caused by lumbar disc herniation: an investigation of biochemical, neurologic, and radiologic predictors of long-term outcome.

We studied 180 adult patients admitted to the Neurological Department, Haukeland Hospital in Bergen, Norway, for a period of 5 years from 1984 to 1988. One hundred fifty-seven patients were followed up 3.9-9.0 years after admittance to the Neurological Department. The purpose of this study was to find out if the total cerebrospinal fluid (CSF) protein concentration could predict the outcome of lumbar disc surgery or conservative treatment in patients with sciatica. Neurologic and radiologic parameters were also included in the investigation. The increase of the CSF total protein concentration in sciatica without spinal block is assumed to be due to leak of plasma proteins into the CSF from the nerve root. A relationship between CSF protein concentrations and certain clinical parameters has been found. At myelography, 10 ml of CSF was collected for analysis. The patients were evaluated for involvement of the nerve root and/or the dural sac, respectively. The neurologic parameters investigated were: straight leg raising tests, paresis, disturbances of sensibility, and altered reflexes. At follow-up, the patients were asked to fill in questionnaires concerning job function, sick leave or disability pension, subjective physical disability and pain perception, and a clinical examination with the same neurologic parameters was performed. Elevated CSF total protein concentration was related to chronic leg pain, leg pain, and subjective physical disability at follow-up. Nonoperated women reported higher subjective physical disability scores and were more often on sick-leave or disability pension than were men at follow-up. Lateral prolapses were associated with good job function outcome and less risk for sick-leave or disability pension. Reduced lower extremity reflexes, laterally located disc herniation and elevated CSF total protein concentration were associated with a favorable long-term outcome in patients with sciatica. CSF proteins as objective measures on nerve root injury are discussed. CSF total protein concentration can be regarded as an indicator of the functional status of the nerve root and a prognostic factor in patients with sciatica.

Adult↗

PubMed1996

[The first case of Vibrio cholerae 0139 in Denmark].

We report the first case of V. cholerae O139 in Denmark. In 1994, a 61-year-old Vietnamese woman was admitted to Aalborg Hospital, Denmark due to severe diarrhoea. The diagnosis was confirmed by biochemical characterization and agglutination in O139 antiserum of a strain isolated from a stool specimen. The woman had stayed in Denmark after family reunion for nine months and had not travelled outside the country. She had not eaten any foods imported from Southeast Asia. The V. cholerae O139 isolate had similar antibiotic susceptibility pattern and contained genes encoding a virulence gene cassette previously identified in O139 isolates from Southeast Asia. Ribotyping showed a banding pattern similar to patterns exhibited by O139 isolates from Bangladesh, India and Thailand. However, the exact mode of transmission of this first Danish case of V. cholerae O139 infection was not determined.

Cholera↗

PubMed1996

[Radiologic examination of patients with head injuries. Late sequelae of minor head injuries, a radiological challenge].

We give a brief summary of the use of computerized tomography and magnetic resonance imaging (MRI) in cases of cranial trauma. The authors advocate more extended use of MRI in this connection; even in less severe cases. The method is much more sensitive than computer tomography, and thus provides a sounder basis for diagnosis and treatment in patients suffering from late sequelae of cranial injuries.

Brain Injuries↗

PubMed1996

Morbidity in patients with posttransplant diabetes mellitus following orthotopic liver transplantation.

It is not well understood whether posttransplant diabetes mellitus (PTDM) following orthotopic liver transplantation (OLTx) alters postoperative morbidity. This study was designed to evaluate this question. All adult patients who received an OLTx between July 1985 and March 1993 (n = 497) were evaluated by retrospective chart review for evidence of PTDM after OLTx. The patients identified with PTDM (n = 26) were case matched with nondiabetic OLTx recipients based on primary liver disease diagnosis, age, gender, date of first OLTx, and survival. Liver synthetic function, number and severity of rejection episodes, graft survival, total number of hospital days within the first year post-OLTx, renal function, and number and type of infection episodes were analyzed to assess differences in morbidity between the PTDM and control patients after OLTx. Of the 497 adult patients who underwent OLTx, 26 (5.2%) were identified as having PTDM within 1 month of discharge. Factors which identified individuals at higher risk for DM after OLTx included higher pre-OLTx fasting blood glucose (P = .04); lower body mass index after OLTx (P = .02); and cyclosporine rather than OKT3 induction (P = .009). Graft survival, synthetic function, and the total number of rejection episodes during the first year were not different between the two groups. The morbidity variables of total number of days in the hospital during the first 12 months, renal function, and type and number of infections were also similar between the two groups. In summary, 5.2% of adult patients developed DM within 1 month of OLTx. Pre-existing insulin resistance, postoperative stress, and immunosuppression medications all likely contribute to the development of overt hyperglycemia after OLTx. Although PTDM can be a consequence of OLTx, it does not have a significant impact on patient outcome in the first year after OLTx.

Adult↗

PubMed1996

Clinical manifestations and molecular epidemiology of Vibrio vulnificus infections in Denmark.

The clinical manifestations of and epidemiological data from 11 patients infected with Vibrio vulnificus admitted to Danish hospitals during the unusually warm summer of 1994 are reported. All patients contracted the disease after exposure to seawater; however, none had consumed seafood. Four patients developed bacteremia, one of whom subsequently died; nine patients, including the four with bacteremia, exhibited skin manifestations. Four patients contracted the disease while fishing; in at least one case the patient had handled eels. All Vibrio vulnificus strains were highly susceptible to 11 antimicrobial agents tested. Plasmid analysis revealed that 8 of 11 strains carried plasmids. Ribotyping using the enzyme HindIII on the 11 strains showed five different types, two of which comprised four strains each. The present study provides the first clinical and epidemiological data about a series of human Vibrio vulnificus infections from a temperate zone.

Adult↗

PubMed1996

Plasmid profiles, restriction fragment length polymorphisms and O-serotypes among Vibrio anguillarum isolates.

A total of 279 Vibrio anguillarum strains were serotyped and examined for plasmid content. Plasmids were subjected to digestion with restriction enzymes. Most strains belonged to serogroup O1 (39%) and O2 (16%). In total 164 strains (53%) carried plasmids. Of the O1 and O2 isolates, 92% and 30%, respectively, carried one or more plasmids. Restriction fragment length polymorphism (RFLP) analysis of plasmid DNA indicated that plasmids belonged to several groups. Each group seemed to be restricted to a single O-serovar. The largest group was the pJM1-like plasmids among most serovar O1 strains. Most of these plasmids were about 67 kb like the pJM1 plasmid, but various derivatives ranged from 26-77 kb. RFLP studies of the 67 kb plasmids revealed 17 different restriction patterns. Some patterns were dominant among European strains whereas others were dominant among North American strains. The results confirmed the applicability of O-serotyping together with plasmid profile and restriction analysis of plasmids for typing of V. anguillarum. They also indicated that plasmids among strains which belonged to the traditional fish pathogenic serogroups, O1 and O2, showed more homology than did strains from most other serogroups, that were usually non-pathogenic, environmental bacteria.

Plasmids↗

PubMed1996

Characterization of atypical Aeromonas salmonicida isolates by ribotyping and plasmid profiling.

A total of 38 strains of atypical Aeromonas salmonicida, three oxidase-negative but otherwise typical Aer. salmonicida, three typical Aer. salmonicida, and two reference strains, isolated from several countries and fish species were examined with respect to rRNA gene restriction patterns (ribotypes) and plasmid profiles. Most epidemiologically unrelated strains had different ribotypes, whereas isolates from the same outbreak were identical. All strains, except one, carried one or more large plasmids (> 55 kbp) and all strains, except two, additionally carried one or more smaller plasmids. Many strains isolated from the same outbreak showed different plasmid profiles although some plasmids were identical. The results suggest the existence of several atypical Aer. salmonicida. It also seems that ribotypes are stable properties for these bacteria while the plasmids are more labile.

Aeromonas↗

PubMed1996

Comparison of a commercial biochemical kit and an oligonucleotide probe for identification of environmental isolates of Vibrio vulnificus.

Methods for the identification and isolation of environmental isolates of Vibrio vulnificus were evaluated. Alkaline peptone water supplemented with polymyxin B and colistin-polymyxin B-cellobiose agar were employed for the isolation of suspected V. vulnificus from water, sediment and shellfish samples. When comparing the identification of putative V. vulnificus obtained with the API 20E assay and an oligonucleotide probe, 29 API 20E profiles were obtained with only four profiles (representing 20 isolates) reaching the identification threshold of V. vulnificus among a total of 66 isolates hybridizing with the probe. The results indicated that, compared with colony hybridization, the API 20E assay was not adequate for the identification of environmental isolates of V. vulnificus.

Bacterial Typing Techniques↗

PubMed1996

Diet after pancreas transplantation.

OBJECTIVE: To determine whether discontinuation of insulin therapy and glucose monitoring and instructions to increase dietary salt and water intake after pancreas transplantation (PTX) resulted in changes in food choices. RESEARCH DESIGN AND METHODS: All PTX recipients who had completed a preoperative diet record, had received their PTX > 6 months before, had stable pancreas and kidney function, and were on a stable diet were invited to submit a 3-day post-PTX diet record. Of the 14 eligible, 11 agreed to participate and completed the study (2 women and 9 men). Their pre- and post-PTX diet records were analyzed by computer program. Weight, glycohemoglobin, blood pressure, medications, and fasting lipids both before and after PTX were also analyzed. RESULTS: The recipients were studied 576 +/- 60 days post-PTX, on average. Total calories and BMI were unchanged after PTX. Before PTX, 34% of calories were in fats, 49% in carbohydrate, and 17% in protein with no change in distribution of calories after PTX, although there was a trend toward greater saturated fat intake. Total salt intake was increased after PTX (P < 0.01) because of sodium bicarbonate administration, although dietary salt intake did not change. The HDL cholesterol concentration increased and cholesterol-to-HDL ratio decreased after PTX (P < 0.05), while the remaining lipids were unchanged. CONCLUSION: Weight, total calories and distribution of calories, and dietary salt were unchanged after PTX, and diet did not explain the changes in HDL cholesterol or cholesterol-to-HDL ratio. These preliminary diet results suggest that greater emphasis on dietary instruction may be needed after PTX.

Body Weight↗

PubMed1996

Atypical Aeromonas salmonicida isolated from diseased turbot (Scophtalmus maximus L.).

Atypical Aeromonas salmonicida were isolated from 3 outbreaks of disease among farmed turbot (Scophthalmus maximus L.) in 3 different farms, 1 from Norway (N1) and 2 from Denmark (DK1 and DK2). In all 3 cases, the incidence of disease and mortality was high and the main characteristic pathological finding was skin ulcers and septicaemia. The isolated bacteria were subjected to a thorough phenotypic and genotypic examination and comparison in the laboratory. All 3 isolates belonged to A. salmonicida but displayed some very different biochemical properties. However, the 2 Danish strains, DK1 and DK2 had identical ribotypes but different from that of N1, whereas the plasmid profiles of DK1 and N1 were identical but different from that of DK2. These observations emphasize the need for an improvement of our understanding of the taxonomy and epidemiology of atypical A. salmonicida.

Aeromonas↗

PubMed1996

Pancreas transplantation: a treatment option for insulin-dependent diabetes mellitus.

The success with which pancreas transplantation normalizes glucose concentration in patients with Type I diabetes mellitus has made it an important treatment option. Most pancreas transplant operations are performed in combination with a kidney transplant, and neither overall patient survival nor renal graft survival is compromised by the addition of a pancreas graft. Pancreas after kidney transplantation and isolated pancreas transplantation are performed less frequently since the pancreas graft success rate remains lower in these operations compared to combined pancreas-kidney transplantation. Pancreas transplantation improves the quality of life and stabilizes or reverses some diabetic microvascular complications, but its impact on the risk of atherosclerotic vascular disease is still unknown. The relative risks and benefits of pancreas transplantation need to be carefully assessed for each candidate through a thorough screening process, regardless of which type of graft is being considered. However, patient counseling and selection will be greatly aided by further research assessing the long-term risks and benefits of all types of pancreas transplantation. Pancreas transplantation will probably remain an important treatment option for some patients with Type I diabetes mellitus until this disease can either be successfully prevented or alternative treatment strategies are developed that provide equal glycaemic control with less or no associated immunosuppression.

Arteriosclerosis↗