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N Weiss

Publications and source records attributed to N Weiss.

At least 37 records · Page 2Linked to original sources
PubMed2001

Sporosarcina aquimarina sp. nov., a bacterium isolated from seawater in Korea, and transfer of Bacillus globisporus (Larkin and Stokes 1967), Bacillus psychrophilus (Nakamura 1984) and Bacillus pasteurii (Chester 1898) to the genus Sporosarcina as Sporosarcina globispora comb. nov., Sporosarcina psychrophila comb. nov. and Sporosarcina pasteurii comb. nov., and emended description of th.

A light-orange-coloured, facultatively anaerobic, rod-shaped bacterium (strain SW28T), which was isolated from seawater in Korea, was taxonomically studied by a polyphasic approach. This organism formed round terminal endospores in swollen sporangia. The peptidoglycan type is A4alpha, based on L-Lys-L-Ala-D-Asp. The predominant menaquinone is MK-7 and the major fatty acid is ante-C15:0. The G+C content of the DNA is 40 mol%. Phylogenetic analysis based on 16S rDNA sequences showed that strain SW28T falls within the radiation of a cluster comprising the rRNA group 2 bacilli and non-Bacillus-type organisms. Strain SW28T showed the highest degree of relatedness to the type strain of Sporosarcina ureae, sharing 96.8% 16S rDNA similarity. Levels of DNA-DNA relatedness between strain SW28T and S. ureae DSM 2281T and the type strains of some Bacillus species forming a coherent phylogenetic cluster are less than 12.5%. On the basis of phenotypic and chemotaxonomic characteristics, 16S rDNA sequence analysis and DNA-DNA relatedness data, it is proposed that strain SW28T should be placed in the genus Sporosarcina as a new species, Sporosarcina aquimarina sp. nov. The type strain is SW28T (= KCCM 41039T = JCM 10887T). From the results of the taxonomic re-evaluation, it is also proposed that Bacillus globisporus, Bacillus psychrophilus and Bacillus pasteurii be transferred to the genus Sporosarcina as Sporosarcina globispora, Sporosarcina psychrophila and Sporosarcina pasteurii, respectively.

Bacillaceae↗
PubMed2001

Jeotgalibacillus alimentarius gen. nov., sp. nov., a novel bacterium isolated from jeotgal with L-lysine in the cell wall, and reclassification of Bacillus marinus Rüger 1983 . as mMrinibacillus marinus gen nov., comb. nov.

A moderately halophilic, round-endospore-forming bacterium (strain YKJ-13T) was isolated from jeotgal, a traditional Korean fermented seafood, and studied by a polyphasic taxonomic approach. This organism was related to the phylogenetic clade comprising members of Bacillus rRNA group 2 and formed a cluster with Bacillus marinus with a bootstrap fidelity value of 93.6%. The peptidoglycan type was A1alpha linked directly through L-Lys. Based on cell morphology, peptidoglycan type and phylogeny, strain YKJ-13T, together with B. marinus, is considered to be a member of Bacillus rRNA group 2. Strain YKJ-13T was also characterized by having MK-7 and MK-8 as the predominant menaquinones and iso-C15:0 as the major fatty acid. The DNA G+C content was 44 mol%. Strain YKJ-13T exhibited a 16S rDNA similarity value of 95.7% with B. marinus DSM 1297T, its closest phylogenetic relative. Levels of 16S rDNA similarity between strain YKJ-13T and other Bacillus spp. were less than 94.2%. Therefore, on the basis of the data presented, the name Jeotgalibacillus alimentarius gen. nov., sp. nov. is proposed for strain YKJ-13T (= KCCM 80002T = JCM 10872T). It is also proposed that B. marinus be reclassified in Marinibacillus gen. nov. as Marinibacillus marinus comb. nov.

Bacillus↗
PubMed2000

Genomic distribution and functional characterisation of two distinct and conserved Plasmodium falciparum var gene 5' flanking sequences.

Approximately 50 highly diverse var genes distributed throughout the haploid genome of the malaria parasite Plasmodium falciparum code for PfEMP1 variants located on the surface of infected erythrocytes. PfEMP1 is involved in cytoadherence of parasitised red blood cells and undergoes antigenic variation through differential expression of var genes. Members of the var gene family are located in chromosome-internal positions on chromosomes 4, 7, 8 and 12, and in subtelomeric regions of all chromosomes. Here we show that there are two distinct and conserved types of 5' upstream regions (var17-type and 5B1-type) of var genes, and suggest that most subtelomeric var genes are flanked by a var17-type 5' upstream sequence. In contrast, 5B1-type 5' upstream are localised to chromosomes that have been shown to contain var genes within chromosome-internal regions. Transcriptional analysis using RT-PCR revealed that var genes flanked by either type of 5' upstream sequence are transcribed in in vitro cultured trophozoite stage parasites. In addition, we have shown that the 5' flanking sequences of four different var genes are able to drive transient expression of the cat reporter gene. Our results suggest that at least the minimal regulatory sequences required for transcription of var genes are conserved among both subgroups of the var gene family. Furthermore, these sequences provide new markers for the investigation of the chromosomal organisation of var genes.

5' Untranslated Regions↗
PubMed2000

Plasmodium falciparum: cloned and expressed CIDR domains of PfEMP1 bind to chondroitin sulfate A.

Adherence of erythrocytes infected with mature asexual Plasmodium falciparum parasites (iRBC) to microvascular endothelial cells contributes to the pathology of P. falciparum malaria. It has been shown that the variant P. falciparum erythrocyte membrane protein 1 (PfEMP1) confers adhesion to a wide range of cell surface receptors. Previously, the cysteine-rich interdomain region (CIDR) of PfEMP1 has been identified as binding site to CD36. We provide evidence that the same region can also mediate binding to chondroitin sulfate A (CSA). CIDR domains of two different parasite strains were expressed in Escherichia coli as a 6xHis-tagged protein. Purified recombinant protein bound to Chinese hamster ovary (CHO) cells which naturally express chondroitin sulfate A. Treatment of wild-type CHO cells with chondroitinase ABC reduced binding up to 94.4%. Competitive binding using soluble CSA inhibited binding to CHO cells by up to 100% at 2 mg/ml and by 62.4% at 0.5 mg/ml, whereas 1 mg/ml heparan sulfate had only a little effect (18.1%). In contrast, a recombinant 6xHis-tagged DBL1 domain showed no binding to wild-type CHO cells. Such an approach of analyzing various domains of PfEMP1 as recombinant proteins may elucidate their functions and may lead to novel anti-adherence therapeutics, especially for maternal malaria infections.

Amino Acid Sequence↗
PubMed2000

Mutations in the low-density-lipoprotein receptor gene in German patients with familial hypercholesterolaemia.

Familial hypercholesterolaemia (FH) is an autosomal dominant disorder of lipid metabolism characterized by elevated low-density lipoproteins (LDL), the formation of tendon and skin xanthomata and the development of premature coronary atherosclerosis. It is caused by a defect in the receptor-mediated hepatic uptake of LDL due to mutations in the LDL receptor. In 25 FH families with a total of 160 members and in two individuals without available relatives, all of German origin, we identified LDL receptor mutations by a multiplex-PCR-based single-strand conformation polymorphism method followed by direct sequencing. Of the 24 mutations found, 15 are missense mutations, 2 are nonsense mutations, 4 are small deletions or insertions leading to frameshifts, 2 are an in-frame insertion and deletion, respectively, and one is a splice site mutation. Propositi carrying mutations that are known to completely abolish receptor function (nonsense and frameshift mutations, missense mutation V480M) had significantly higher untreated total and LDL-cholesterol levels compared to those patients carrying missense and in-frame insertion mutations of unknown functional consequence, which may lead to either reduced or completely abolished receptor function (11.30+/-1.64 vs 9.76+/-1.50 mmol/L, and 9.39+/-1.23 vs 7.99+/-1.45 mmol/L, respectively). These results confirm the clinical and molecular heterogeneity of FH and the influence of different functional classes of mutations on lipid values.

Adolescent↗
PubMed2000

Risk factor scoring for predicting venous thromboembolism in obstetric patients.

OBJECTIVE: The aim of this study was to develop a risk factor scoring system for the prediction of venous thromboembolism in obstetric patients. STUDY DESIGN: We conducted a retrospective case-control study of all pregnant or postpartum women admitted to the Jack D. Weiler Hospital from 1987 through 1998 with a discharge diagnosis indicating thromboembolism. For each study subject the three women who were delivered immediately before that index patient were selected for the control group. Data collected included the following: history of thrombosis, age, body mass index, previous abdominal surgical procedures, presence of systemic diseases, and blood type. Each patient was assigned a score that was based on the risk factors identified. RESULTS: We identified 21 patients who had sustained thromboembolic events during pregnancy or 6 weeks post partum. Nineteen of the thromboembolic events (90%) were diagnosed during pregnancy, and these cases were distributed throughout gestation-8 (42%) in the first trimester, 2 (10%) in the second trimester, and 9 (48%) in the third trimester. Six (28%) of these patients had pulmonary embolisms. Two cases of postpartum thromboembolic events were documented. Both were cases of pulmonary embolism. There was 1 maternal death. Patients with a score >2 were at significantly increased risk for having a thromboembolism, with an odds ratio of 4.8 (P <.05). The sensitivity, specificity, positive predictive value, and negative predictive value of this cutoff point were 21%, 95%, 57%, and 78%, respectively. CONCLUSION: Obstetric patients with high risk factor scores were at increased risk for thromboembolism.

ABO Blood-Group System↗
PubMed2000

Frigoribacterium faeni gen. nov., sp. nov., a novel psychrophilic genus of the family Microbacteriaceae.

The taxonomic position of five actinobacterial strains isolated from dust, an animal shed, the air inside a museum and soil was investigated using a polyphasic approach. The growth characteristics were unusual for actinomycetes. Optimal growth was at temperatures ranging from 2 to 10 degrees C. After small-step adaptation (5 degrees C steps) to higher temperatures, the strains were also able to grow at 20 degrees C. Cell wall analyses revealed that the organisms showed a hitherto undescribed, new group B-type peptidoglycan [type B2beta according to Schleifer & Kandler (1972), but with lysine instead of ornithine]. All strains contained menaquinone MK-9. Mycolic acids were not detected. Diphosphatidylglycerol, phosphatidylglycerol and an unknown glycolipid were detected in the polar lipid extracts. The main fatty acids were 12-methyl-tetradecanoic acid (15:0 anteiso), 12-methyl-tetradecenoic acid (15:1 anteiso), 14-methyl-pentadecanoic acid (16:0 iso) and 14-methyl-hexadecanoic acid (17:0 iso), as well as an unusual compound identified as 1,1-dimethoxy-anteiso-pentadecane (15:0 anteiso-DMA). The G+C content of DNA was approximately 71 mol%. The results of 16S rRNA gene sequence comparisons revealed that the strains represent a new lineage in the suborder Micrococcineae and the family Microbacteriaceae of the order Actinomycetales. On the basis of these results the new genus Frigoribacterium gen. nov. is proposed, harbouring the new species Frigoribacterium faeni sp. nov. (type strain = 801T = DSM 10309T).

Actinomycetales↗
PubMed2000

Characterization of Leuconostoc gasicomitatum sp. nov., associated with spoiled raw tomato-marinated broiler meat strips packaged under modified-atmosphere conditions.

Lactic acid bacteria (LAB) associated with gaseous spoilage of modified-atmosphere-packaged, raw, tomato-marinated broiler meat strips were identified on the basis of a restriction fragment length polymorphism (RFLP) (ribotyping) database containing DNAs coding for 16S and 23S rRNAs (rDNAs). A mixed LAB population dominated by a Leuconostoc species resembling Leuconostoc gelidum caused the spoilage of the product. Lactobacillus sakei, Lactobacillus curvatus, and a gram-positive rod phenotypically similar to heterofermentative Lactobacillus species were the other main organisms detected. An increase in pH together with the extreme bulging of packages suggested a rare LAB spoilage type called "protein swell." This spoilage is characterized by excessive production of gas due to amino acid decarboxylation, and the rise in pH is attributed to the subsequent deamination of amino acids. Protein swell has not previously been associated with any kind of meat product. A polyphasic approach, including classical phenotyping, whole-cell protein electrophoresis, 16 and 23S rDNA RFLP, 16S rDNA sequence analysis, and DNA-DNA reassociation analysis, was used for the identification of the dominant Leuconostoc species. In addition to the RFLP analysis, phenotyping, whole-cell protein analysis, and 16S rDNA sequence homology indicated that L. gelidum was most similar to the spoilage-associated species. The two spoilage strains studied possessed 98.8 and 99.0% 16S rDNA sequence homology with the L. gelidum type strain. DNA-DNA reassociation, however, clearly distinguished the two species. The same strains showed only 22 and 34% hybridization with the L. gelidum type strain. These results warrant a separate species status, and we propose the name Leuconostoc gasicomitatum sp. nov. for this spoilage-associated Leuconostoc species.

Animals↗
PubMed1999

Influence of folic acid, pyridoxal phosphate and cobalamin on plasma homocyst(e)ine levels and the susceptibility of low-density lipoprotein to ex-vivo oxidation.

Mild hyperhomocyst(e)inaemia is a risk factor for atherosclerotic vascular disease. In-vitro studies have shown that autooxidation of homocyst(e)ine is accompanied by the generation of oxygen radicals. This may lead to oxidative modification of low-density lipoproteins (LDL) and promote atherosclerotic vascular lesions. In male patients with peripheral arterial occlusive disease we determined fasting and post methionine load homocyst(e)ine levels by high performance liquid chromatography and the susceptibility of their LDL particles to ex-vivo oxidation by continously measuring the conjugated diene production induced by incubation with copper ions. Oxidation resistance (expressed as lag time), maximal oxidation rate, and extent of oxidation (expressed of total diene production) of LDL from patients with normal or mildly elevated homocyst(e)ine levels did not differ significantly. Folic acid, pyridoxal phosphate and cobalamin supplementation significantly decreased plasma homocyst(e)ine levels in hyperhomocyst(e)inaemic patients. This went along with a significant decrease in the extent of LDL oxidation and additionally increased HDL-cholesterol levels. The clinical relevance of these findings for the long-term course of atherosclerotic vascular disorders has to be determined by intervention studies.

Adult↗
PubMed1999

Dust-borne bacteria in animal sheds, schools and children's day care centres.

A total of 316 bacterial strains, including psychrophiles, mesophiles and thermophiles, were isolated and identified from indoor dusts in schools, children's day care centres and animal sheds. Several species which had not previously been reported from indoor environments were found: Sphingomonas, Brevibacterium, Nocardiopsis, Deinococcus and Rhodococcus/Gordona. A new psychrophilic actinomycete genus was also found in animal sheds, representing a new undescribed peptidoglycan type and an unusual whole-cell fatty acid composition. The indoor dusts of animal sheds contained mainly the Gram-negative genera Pseudomonas, Pantoea, Flavobacterium and Xanthomonas early in the indoor feeding season, but changed to a composition dominated by Bacillus, Micrococcus and mesophilic and thermophilic actinomycetes towards the end of the season. The dust contained, and air-borne bacterial flora in schools and day care centres were dominated by, Gram-positive bacilli and actinomycetes, notably Bacillus cereus, Brevibacillus brevis, B. licheniformis, B. subtilis and species of Arthrobacter, Corynebacterium, Rhodococcus/Gordona, Nocardiopsis sp., Deinococcus, Staphylococcus and Micrococcus. Indoor air and dust contained Klebsiella oxytoca, Acinetobacter calcoaceticus, Ac. lwoffi, Bacillus cereus and Nocardiopsis dassonvillei with the status of hazard group II. Indoor dusts of animal sheds contained eight different 3-hydroxy fatty acids, the 2-hydroxy fatty acid 14:0 and two 10-methyl fatty acids, whereas in dusts from schools and day care centres, these were below the detection level (< 3.5 ng mg-1). The 3-and 2-hydroxy fatty acids could be assigned to one or more of the dust-contained cultivable strains, but 10-methyl C16:0 was not present in any of the strains isolated. The dusts from schools and children's day care centres contained 0.2-0.3 ng of endotoxin mg-1 and 0.5-1.4 ng of beta-D-glucan mg-1, whereas the dusts from animal sheds contained more 0.3-41 ng mg-1 and 8-35 ng mg-1, respectively.

Air Microbiology↗
PubMed1999

Does transcervical intra-fallopian insemination improve pregnancy rates in cases of oligoteratoasthenozoospermia? A prospective, randomized study.

The relatively low pregnancy rates (PR) after treatment of patients with oligoteratoasthenozoospermia (OTA) result in a search for different treatment modalities. The objective of this study was to assess the efficacy of transcervical intrafallopian insemination (IFI) with husband's semen in comparison to intrauterine insemination (IUI) in couples with OTA. A prospective, randomized study included 30 couples with OTA-related infertility (according to WHO criteria). The female patients underwent individually adjusted controlled ovarian stimulation by gonadotropins. Spermatozoa was prepared using the Percoll 70% technique and insemination was performed 36-40 h after human chorionic gonadotropin (HCG) administration. The Tomcat Catheter was used for IUI and the Jansen-Anderson Catheter for IFI to the fallopian tube leading to the ovary that contained more dominant follicles. The couples were divided according to sperm count, into group A (9 couples): < 10 mill ml-1 and group B (21 couples): > 10 mill ml-1. Within the groups the patients were randomly assigned for IUI or IFI treatment. Among group B couples, two pregnancies out of 15 IUI cycles (13.3% PR) and two pregnancies out of 18 IFI cycles (11.1% PR) were achieved. Group A patients completed 7 IUI and 9 IFI treatment cycles with no pregnancies observed. These data did not demonstrate a statistically significant advantage for either technique.

Adult↗
PubMed1999

Transient marked atelectasis: an unusual complication of asthma in pregnancy.

We present an unusual case in which a patient with asthma presented with acute respiratory distress of acute onset, secondary to marked atelectasis of the right middle and lower lobes, which resolved within 24 hr following administration of increased doses of intravenous steroids, inhalation therapy (beta-agonists and steroids), and pulmonary physiotherapy. This transient occurrence responding to basic therapeutic measures was considered consistent with the release of a mucous plug which had caused the above obstruction and associated symptomatology and radiographic findings. This case illustrates and supports the practice of chest imaging in patients with atypical presentations of asthma and stresses the importance of pulmonary physiotherapy and bronchodilatory therapy as primary therapeutic agents in cases of mucous plug-associated atelectasis.

Adult↗
PubMed1999

Reclassification of Brevibacterium oxydans (Chatelain and Second 1966) as Microbacterium oxydans comb. nov.

Phylogenetic and chemotaxonomic analyses indicate that Brevibacterium oxydans is closely related to species of the genus Microbacterium, namely Microbacterium liquefaciens, Microbacterium luteolum and Microbacterium saperdae. DNA-DNA reassociation values of less than 60% between Brevibacterium oxydans and these three Microbacterium species support the distinctness of this misclassified Brevibacterium species, which is reclassified as Microbacterium oxydans comb. nov.

Actinomycetales↗
PubMed1999

Reclassification of Brevibacterium incertum (Breed 1953) as Desemzia incerta gen. nov., comb. nov.

Phylogenetic analysis of 16S rDNA indicates that Brevibacterium incertum is not a member of the genus Brevibacterium but related to species of the genus Carnobacterium. Hence, Brevibacterium incertum is not a member of the class Actinobacteria but belongs to the phylogenetically defined broad Bacillus-Lactobacillus cluster. Based upon properties that taxonomically clearly distinguishes Brevibacterium incertum from species of the phylogenetic sister genus Carnobacterium, Brevibacterium incertum is reclassified as Desemzia incerta gen. nov., comb. nov.

Base Sequence↗
PubMed1998

Heterozygosity for the missense mutation Ala370-->Thr in exon 8 of the low density lipoprotein receptor gene does not cause hypercholesterolemia.

Familial hypercholesterolemia (FH) is caused by mutations in the low-density lipoprotein (LDL) receptor gene. We used a multiplex-PCR based single-strand conformation polymorphism analysis to screen the promotor region and all 18 exons of the LDL receptor gene for mutations in patients clinically diagnosed as having FH to identify their particular gene defect. An affected proband was found to be heterozygous for a missense mutation, replacing guanine to adenine at nucleotide 1171 of exon 8 of the gene. This mutation is predicted to cause a substitution of alanine to threonine at codon 370 (A370T). The base exchange abolishes a HaeIII restriction site. PCR of exon 8 followed by restriction enzyme digestion with HaeIII conveniently allowed to screen the whole family and 101 unrelated normocholesterolemic subjects from the same ethnic background for the presence of this mutation. The A307T mutation did not cosegregate with the clinical phenotype of hypercholesterolemia in the affected family. Furthermore the mutation was identified in a heterozygous state in 12 out of 101 and in a homozygous state in 1 out of 101 normocholesterolemic subjects, indicating that this mutation is a frequent genetic variation of the LDL receptor gene in the population examined. Lipid values of probands carrying the wild type LDL receptor allele and the mutation in a heterozygous state did not differ significantly. The proband carrying the mutation on both LDL receptor alleles had high normal cholesterol and LDL cholesterol levels. The A370T mutation represents the third single-amino acid change of the LDL receptor protein reported so far, which, in a heterozygous state, is not associated with the clinical phenotype of familial hypercholesterolemia. The pathophysiologic significance of homozygosity for this mutation remains to be clarified.

Adult↗