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L Herman

Publications and source records attributed to L Herman.

At least 19 recordsLinked to original sources
PubMed1999

Typing of Listeria monocytogenes strains by repetitive element sequence-based PCR.

Listeria monocytogenes strains possess short repetitive extragenic palindromic (REP) elements and enterobacterial repetitive intergenic consensus (ERIC) sequences. We used repetitive element sequence-based PCR (rep-PCR) to evaluate the potential of REP and ERIC elements for typing L. monocytogenes strains isolated from humans, animals, and foods. On the basis of rep-PCR fingerprints, L. monocytogenes strains were divided into four major clusters matching origin of isolation. rep-PCR fingerprints of human and animal isolates were different from those of food isolates. Computer evaluation of rep-PCR fingerprints allowed discrimination among the tested serotypes 1/2a, 1/2b, 1/2c, 3b, and 4b within each major cluster. The index of discrimination calculated for 52 epidemiologically unrelated isolates of L. monocytogenes was 0.98 for REP- and ERIC-PCR. Our results suggest that rep-PCR can provide an alternative method for L. monocytogenes typing.

Animals↗
PubMed1998

Lyme carditis: a rare presentation in an unexpected setting.

A case is reported of a 27-year-old man who presented to an inner city trauma center after he had experienced several seizure-like episodes. He was diagnosed with Lyme carditis and required 6 weeks of treatment with intravenous ceftriaxone for complete resolution of his symptoms. The case is discussed along with a review of the literature.

Adult↗
PubMed1998

Typing of Bacillus sporothermodurans and other Bacillus species isolated from milk by repetitive element sequence based PCR.

When analysing raw milk for the presence of Bacillus sporothermodurans, 11 Bacillus strains were isolated which could be differentiated from known Bacillus, Brevibacillus and Paenibacillus spp. by different primer specificity in PCR experiments, indicating that they probably belong to Bacillus species as yet undescribed. Using repetitive element sequence based PCR (REP-PCR), these 11 strains could be clearly distinguished from B. sporothermodurans as well as from each other. Eighty-five B. sporothermodurans strains were characterized by a typical REP-pattern. Using REP-PCR combined with separation on non-denaturing polyacrylamide gel electrophoresis and silver staining, individual B. sporothermodurans strains could be discriminated, which was not possible by methods previously published.

Animals↗
PubMed1998

Unidentified Listeria-like bacteria isolated from cheese.

Unidentified Listeria-like bacteria, which lack only one of the phenotypic characteristics used to confirm Listeria spp., were isolated from cheese during routine analysis for Listeria monocytogenes. The VIDAS Listeria assay and the Listeria specific PCR or DNA probe assays used did not identify these strains as Listeria species. This group of bacteria was studied for its homogeneity using rep-PCR and PFGE. Sequence analysis of the 16S rRNA gene showed a homology of 94% to established Listeria spp., implicating a closer relationship than that between Listeria spp. and Brochothrix spp.

Bacterial Typing Techniques↗
PubMed1997

Social relationships among young adults with insulin-dependent diabetes mellitus: ten-year follow-up of an onset cohort.

Past cross-sectional studies have suggested that young adults with insulin-dependent (Type 1) diabetes mellitus (IDDM) may experience problems in their close peer relationships. For 10 years, we have followed an onset cohort of children and adolescents with IDDM (n = 57) and an age-matched group who were originally recruited after an acute illness, accident, or injury (n = 54). Now aged 19-26 years, these two groups were compared in terms of their friendship patterns, dating and love experiences, and sense of loneliness. All subjects in both groups had at least one friend. However, the IDDM group reported fewer friendships overall. The difference was accounted for by the number of less intimate friends. The two groups had similar frequencies of current romantic partners (IDDM = 63%; comparison group = 64%). While dating attitude and dating assertiveness did not differ between groups, some differences were found in terms of experiences of a primary love relationship. IDDM patients experienced less trust and sense of intimate friendship in these love relationships. No differences in loneliness were found. The preponderance of our findings indicate that the two groups had similar patterns and experiences of close peer relationships. Thus, the study does not suggest that IDDM leads to serious problems in forming social relationships for these patients during the transition to young adulthood. On the other hand, the IDDM patients' lower level of trust and intimacy within love relationships are consistent with other findings from this study suggesting specific areas of lowered self-worth that appear in social relationships.

Adolescent↗
PubMed1997

Consequences of irregular versus continuous medical follow-up in children and adolescents with insulin-dependent diabetes mellitus.

OBJECTIVES: To study the social and family characteristics of patients with insulin-dependent diabetes mellitus with irregular versus continuous clinical follow-up and to study the medical outcomes of patients with these follow-up patterns. METHODS: An onset cohort of 61 children and adolescents with insulin-dependent diabetes mellitus and their parents were studied. Aspects of their social and family environment were assessed at study inception and examined in relation to frequency of follow-up early in the course of the illness. Follow-up was dichotomized so that patients with continuous follow-up were compared with patients with irregular follow-up, who were defined as those missing 1 full year of planned medical appointments during the second through fourth years after diagnosis. Patients with irregular and continuous follow-up were compared in terms of acute metabolic complications, glycemic control, and retinopathy status during a 10-year period. RESULTS: Compared with individuals with continuous follow-up, patients with irregular clinical visits were more likely to be from families of lower socioeconomic class levels, have a parental history of separation and divorce, and were members of families that reported being least openly expressive of positive emotions. Poor glycemic control in year 1 was associated with irregular follow-up in years 2 through 4. Patients with irregular follow-up continued to have worse glycemic control in years 2 through 4 than patients with continuous follow-up. However, in years 7 and 10 their glycemic control no longer differed from patients with continuous follow-up. More episodes of diabetic ketoacidosis occurred in the irregular follow-up group. Finally, retinopathy occurred more frequently among those in the irregular follow-up group. CONCLUSION: Early irregular clinical follow-up should be considered a risk factor for complications of insulin-dependent diabetes mellitus.

Adolescent↗
PubMed1997

Psychological adjustment to IDDM: 10-year follow-up of an onset cohort of child and adolescent patients.

OBJECTIVE: To evaluate the psychological adjustment of young adults with IDDM in comparison with similarly aged individuals without chronic illness. RESEARCH DESIGN AND METHODS: An onset cohort of young adults (n = 57), ages 19-26 years, who have been followed over a 10-year period since diagnosis, was compared with a similarly aged group of young adults identified at the time of a moderately severe, acute illness (n = 54) and followed over the same 10-year period. The groups were assessed at 10-year follow-up in terms of 1) sociodemographic indices (e.g., schooling, employment, delinquent activities, drug use), 2) psychiatric symptoms, and 3) perceived competence. In addition, IDDM patients were examined for longitudinal change in adjustment to diabetes. RESULTS: The groups differed only minimally in terms of sociodemographic indices, with similar rates of high school graduation, post-high school education, employment, and drug use. The IDDM group reported fewer criminal convictions and fewer non-diabetes-related illness episodes than the comparison group. There were no differences in psychiatric symptoms. However, IDDM patients reported lower perceived competence, with specific differences found on the global self-worth, sociability, physical appearance, being an adequate provider, and humor subscales. The IDDM patients reported improving adjustment to their diabetes over the course of the 10-year follow-up. CONCLUSIONS: Overall, the young adults with IDDM appeared to be as psychologically well adjusted as the young adults without a chronic illness. There were, however, indications of lower self-esteem in the IDDM patients that could either portend or predispose them to risk for future depression or other difficulties in adaptation.

Acute Disease↗
PubMed1996

Repetitive element sequence based polymerase chain reaction for typing of Brucella strains.

A collection of 40 Brucella strains, including 19 clinical B.canis isolates, was analyzed using ERIC-PCR and REP-PCR. PCR amplification using primers REP 1R-I and REP 2-I provided distinct patterns for Brucella spp. All Brucella strains could be discriminated at least to the species level. ERIC-PCR, employing ERIC 1R and ERIC 2 as primers was less discriminative for Brucella, only allowing a discrimination to the genus level with occasional discrimination between individual strains. It can be concluded that rep PCR is a promising fingerprinting method for the evaluation of an outbreak.

Animals↗
PubMed1996

The WHO multicenter study on Listeria monocytogenes subtyping: random amplification of polymorphic DNA (RAPD).

As part of a WHO multicenter study on Listeria monocytogenes subtyping methods the random amplification of polymorphic DNA (RAPD)-technique was evaluated. Six participants were asked to use a standard protocol to analyse a set of 80 L. monocytogenes strains. This set contained 22 groups of epidemiologically linked isolates and 11 pairs of duplicate strains. Using three different 10-mer primers the median reproducibility of the RAPD-results obtained by the six participants was 86.5% (range 0-100%). Failure in reproducibility was mainly due to results obtained with one particular primer. The number of epidemiological groups found to be homogeneous varied from 1-22 (median 16). However, for some groups an inhomogeneity was found by the majority of participants. The overall correlation between the results from the different participants ranged from 32 to 85%.

Bacterial Typing Techniques↗
PubMed1996

Repetitive element sequence-based PCR for species and strain discrimination in the genus Listeria.

Repetitive element sequence-based PCR (rep-PCR) was used to generate DNA fingerprints for Listeria spp. Two primer sets (REP 1R-I REP 2-I and ERIC 1R ERIC 2) used in respectively REP- and ERIC-PCR revealed that bacteria of the genus Listeria possess short repetitive extragenic palindromic elements and enterobacterial repetitive intergenic consensus sequences. Specific band profiles obtained by ERIC-PCR enabled the identification of Listeria species. With both REP- and ERIC-PCR the L. monocytogenes serotypes 1/2a, 1/2b, 1/2c, 3b and 4b could be clearly distinguished from each other. Within the serotype 1/2a, REP-PCR showed a higher discriminative potential than ERIC-PCR and a comparable discriminative potential as RAPD combining 3-4 primers.

Base Sequence↗
PubMed1994

Isolation and characterization of two bacteriocins produced by Enterococcus faecium strains inhibitory to Listeria monocytogenes.

A total of 4000 bacterial strains were isolated from milk, cheese and from different samples taken on the farm (silage, faeces) and screened for their antimicrobial activity against Listeria monocytogenes. Only eight of the almost 4000 strains exhibited inhibitory activity in the cell-free supernatant fluid. Two different Enterococcus strains (RZS C5 and RZS C13) were chosen for further study. Plasmid profile analysis of both revealed that RZS C5 contained a 4 kb plasmid while RZS C13 contained a 23 kb plasmid. The inhibitory compounds were proteinaceous and active against all Listeria spp. tested while most of the lactic acid bacteria were insensitive. Weak inhibition was also detected against Clostridium perfringens and some Bacillus spp. Cross-inhibition tests showed different profiles. The bacteriocins were heat-resistant and were very stable during storage, especially at low pH values. Their molecular weight was estimated at +/- 3.0 kDA. Addition of 200 AU/ml of bacteriocin resulted in an initial rapid decrease of the number of viable L. monocytogenes cells followed by slower a logarithmic decrease.

Animals↗
PubMed1994

The evolution of the chicken sarcomeric myosin heavy chain multigene family.

This manuscript describes the chicken sarcomeric myosin heavy chain (MyHC) multigene family and how it differs from the sarcomeric MyHC multigene families of other vertebrates. Data is discussed that suggests the chicken fast MyHC multigene family has undergone recent expansion subsequent to the divergence of avians and mammals, and has been subjected to multiple gene conversion-like events. Similar to human and rodent MyHC multigene families, the chicken multigene family contains sarcomeric MyHC genes that are differentially regulated in developing embryonic, fetal, and neonatal muscles. However, unlike mammalian genes, chicken fast MyHC genes expressed in developing muscles are also expressed in mature muscle fibers as well. The potential significance of conserved and divergent sequences with the MyHC rod domain of five fast chicken isoforms that have been cloned and sequenced is also discussed.

Animals↗
PubMed1993

Glutathione depletion increases the cytotoxicity of melphalan to PC-3, an androgen-insensitive prostate cancer cell line.

Prostate cancer that is androgen-insensitive is unresponsive to a wide spectrum of cytotoxic agents, including all of the alkylating agents. Since a major pathway for the detoxification of the alkylating agents is conjugation with glutathione (GSH), GSH depletion has proved to be effective as a technique to restore melphalan sensitivity in melphalan-resistant cancer cell lines. However, the effect of GSH depletion has not been widely studied in tumor cell lines that have not developed resistance due to previous exposure to alkylating agents. Thus, we decided to investigate GSH depletion as a technique to increase melphalan cytotoxicity to PC-3 cells, an androgen-insensitive prostate cancer line. After 2 and 6 h incubation with 0.25-5 microM melphalan, virtually no effect was observed on either clonogenic lethality or MTT viability until 5 microM exposures. A 24-h incubation of the cells with 100 microM buthionine sulfoximine (BSO), an inhibitor of GSH synthesis, reduced the GSH content by 70%-75%. Following GSH depletion, an increase in clonogenic lethality and a decrease in MTT viability occurred after exposure to concentrations as low as 0.25 microM. The dose modification factor ranged from 2.9 after 2 h incubation to 4.5 at 6 h. These results provide support for additional studies in prostate cancer for further investigation of GSH depletion as a technique to induce sensitivity to alkylating agents in this chemotherapy-resistant tumor.

Buthionine Sulfoximine↗
PubMed1993

Prospective comparison of T2-weighted fast spin-echo, with and without fat suppression, and conventional spin-echo pulse sequences in the upper abdomen.

PURPOSE: To evaluate use of fast spin-echo (FSE) magnetic resonance imaging with and without fat suppression in the liver and upper abdomen. MATERIALS AND METHODS: Conventional spin-echo (SE) T2-weighted, FSE T2-weighted, and fat-suppressed FSE T2-weighted images from 37 patients strongly suspected to have focal hepatic lesions were evaluated. RESULTS: Quantitative analysis demonstrated that fat-suppressed FSE imaging had the highest lesion-liver contrast-to-noise ratio; conventional SE imaging, the lowest. In a qualitative analysis, FSE imaging was preferred. In a rank order analysis, FSE imaging was preferred 83% of the time and fat-suppressed FSE imaging 17% of the time as regards overall image quality; fat-suppressed FSE imaging was preferred 64% of the time, FSE imaging 23% of the time, and conventional SE imaging 13% of the time as regards signal abnormality detection. CONCLUSION: FSE imaging with and without fat suppression is a potentially useful pulse sequence for evaluating the upper abdomen.

Abdomen↗
PubMed1992

Identification of Brucella spp. by using the polymerase chain reaction.

The application of two synthetic oligonucleotides as probes and as primers in the polymerase chain reaction is presented for a specific, sensitive, and quick identification of Brucella spp. The specific oligonucleotide sequences were chosen on the basis of a 16S rRNA sequence alignment between Brucella abortus and Agrobacterium tumefaciens.

Base Sequence↗
PubMed1990

Cloning and sequence analysis of truncated T-DNA inserts from Nicotiana tabacum.

Transgenic plants produced by Agrobacterium-mediated transformation usually have one or a few stable and intact T-DNA insertions. However, in a significant number of the transformants Southern blot analysis has revealed the occurrence of aberrant T-DNA insertions missing one or both ends. During the study of this phenomenon, we obtained KmR Nicotiana tabacum clones after cocultivation with an Agrobacterium strain containing a promoterless nptII gene located internally in the T-DNA. Expression of this nptII gene requires a break in the T-DNA region upstream from the nptII-coding sequence and insertion of the truncated T-DNA in a transcriptionally active plant DNA region. The most conspicuous result from Southern analyses on four such KmR plant clones is that they contain several T-DNAs truncated at other positions besides the upstream region of the nptII sequence. Four truncated T-DNA insertions have been cloned. Two insertions contain the nptII gene fused to plant expression signals and are missing the right part of the T-DNA. Another is missing the left T-DNA part and the last T-DNA is lacking both ends. Sequence analysis of the T-DNA::plant junctions has shown that the T-DNA breakpoints are randomly distributed and do not show obvious homologies to one another or to the border consensus sequence. S1-type mapping of the most strongly expressed plant genome::nptII fusion revealed a specific transcription start point and putative TATA and CAAT boxes in the upstream plant DNA region; the steady-state nptII mRNA in these plants is about 20 times more abundant than in transgenic Pnos-nptII plants.

Base Sequence↗