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N Weiss

Publications and source records attributed to N Weiss.

At least 91 records · Page 5Linked to original sources
PubMed1994

A trial of the synthetic malaria vaccine SPf66 in Tanzania: rationale and design.

The development of a safe, affordable and effective malaria vaccine to form part of control schemes in malaria endemic countries is a priority for researchers and public health officials. SPf66 is the first malaria vaccine to have shown partial protection against natural challenge in a phase III trial carried out in a hypoendemic area of Colombia. This paper describes the rationale and design of the first field trial of SPf66 outside South America, and the first to be conducted in an area of high perennial transmission.

Adult↗
PubMed1994

Clostridium thermoalcaliphilum sp. nov., an anaerobic and thermotolerant facultative alkaliphile.

An anaerobic and thermophilic alkaliphile, strain JW/YL23-2T (T = type strain), was isolated from sewage sludge obtained from a sewage plant in Atlanta, Ga. At pH 10.1 and 50 degrees C, the doubling time of this strain was 19 min. Strain JW/YL23-2T, a motile rod-shaped bacterium with 2 to 12 peritrichous flagella, exhibited a negative Gram stain reaction but was gram-type positive as judged by the polymyxin B test. No heat-stable (85 degrees C, 15 min) endospores were detected. At 50 degrees C, growth occurred at pH values ranging from 7.0 to 11.0; the optimum pH was 9.6 to 10.1. The temperature range for growth ranged from 27 to 57.5 degrees C; the optimum temperature was 48 to 51 degrees C (pH 10.1). Dissimilatory sulfate reduction was not detected. The organism utilized glucose, fructose, sucrose, maltose, cellobiose, and Casamino Acids. The DNA G+C content was 32 mol% (as determined by chemical analysis). A 16S rRNA sequence analysis revealed a 2% inferred evolutionary distance to Clostridium paradoxum. However, the cell wall type of strain JW/YL23-2T was A4 beta (L-Orn-D-Asp), while that of C. paradoxum was A1 tau (m-diaminopimelic acid direct). On the basis of the alkaline pH values and high temperatures for optimal growth, the inability to form spores, and other characteristics different from C. paradoxum characteristics, strain JW/YL-23-2 was placed in a new species, Clostridium thermoalcaliphilum; JW/YL23-2 (= DSM 7309) is the type strain of this new species.

Base Sequence↗
PubMed1994

Transfer of Propionibacterium innocuum Pitcher and Collins 1991 to Propioniferax gen. nov. as Propioniferax innocua comb. nov.

16S ribosomal DNA analysis indicates that Propionibacterium innocuum is a phylogenetic neighbor of Luteococcus japonicus and that this pair of organisms branches intermediately between the genus Propionibacterium on the one side and the genera Aeromicrobium and Nocardioides on the other side. Phenotypically, strains of P. innocuum differ from species of Propionibacterium by exhibiting aerobic growth and possessing arabinose in the cell wall, they differ from species of Aeromicrobium and Nocardioides by the formation of propionic acid, and they differ from species of Luteococcus in morphology. Consequently, P. innocuum should not be classified with authentic Propionibacterium species, and the transfer of P. innocuum Pitcher and Collins 1991 to a new genus, Propioniferax, as Propioniferax innocua gen. nov., comb. nov. is proposed.

DNA, Bacterial↗
PubMed1994

Primary identification of Aureobacterium spp. isolated from clinical specimens as "Corynebacterium aquaticum".

Over a 6-year period 11 yellow-pigmented gram-positive rods (GPRs) with an oxidative carbohydrate metabolism were isolated from clinical specimens or were received as reference cultures and tentatively identified as "Corynebacterium aquaticum" according to the guide of Hollis and Weaver for the differentiation of GPRs (D. G. Hollis and R. E. Weaver, Gram-Positive Organisms: a Guide to Identification, 1981). Because these isolates seemed to be rather heterogeneous, comparative analyses with the type strain of "C. aquaticum" as well as six type strains of species belonging to the genus Aureobacterium were performed by biochemical and chemotaxonomic methods. Only four clinical strains were found to be "C. aquaticum," whereas seven strains were found to belong to the genus Aureobacterium. Discriminative phenotypic reactions between "C. aquaticum" and Aureobacterium spp. included hydrolysis of gelatin and casein (both reactions negative for "C. aquaticum" strains but positive for most Aureobacterium strains). Moreover, peptidoglycan analysis provided a reliable means of differentiating yellow-pigmented GPRs at the genus level (diaminobutyric acid as the interpeptide bridge in "C. aquaticum" and glycine-ornithine as the interpeptide bridge in Aureobacterium spp.). Antimicrobial susceptibility testing revealed that vancomycin showed an intermediate MIC for three of the four clinical "C. aquaticum" isolates, whereas all Aureobacterium strains were susceptible to vancomycin. To our knowledge, this is the first report outlining the isolation of Aureobacterium spp. from clinical specimens. However, Aureobacterium isolates could not be identified to the species level by the tests used in the study.

Actinomycetales↗
PubMed1993

Xanthoma disseminatum: a rare normolipemic xanthomatosis.

Xanthoma disseminatum (XD) is a rare benign histiocytic disorder with extensive cutaneous and mucous membrane xanthomas in normolipemic patients. We describe the 9-year course of a 25-year-old white man who presented with multiple brownish-reddish papulous skin tumors that developed over 3 years and remained relatively constant, with spontaneous regression and progression of individual lesions since. In addition, there was asymptomatic xanthomatous infiltration of the epipharnyx and symptomatic infiltration of the synovial membrane of the left knee joint leading to restriction of movement. Histologically, the corium was infiltrated by large lipid-storing macrophages, polynucleated histiocytic giant cells of the Touton and the foreign body type. Immunhistochemically, the lipid-storing cells could be classified as macrophage/monocyte derived cells distinctly different from Langerhans' cells without proliferative activity. The clinical picture and course as well as laboratory findings indicating normolipidemia made it possible to differentiate XD from other normolipemic xanthomatosis, especially juvenile xanthogranuloma, eruptive histiocytoma, and histiocytosis X. The etiology of XD is still unknown. It is possible to differentiate xanthoma disseminatum from malignant histiocytosis X by the clinical picture and immunhistochemical studies. Thus it is no longer justified to administer cytostatic treatment for this disorder.

Adult↗
PubMed1993

Proposal of six new species in the genus Aureobacterium and transfer of Flavobacterium esteraromaticum Omelianski to the genus Aureobacterium as Aureobacterium esteraromaticum comb. nov.

Twelve strains placed in the genera Flavobacterium, Pseudomonas, and Aureobacterium, including soil isolates, were characterized taxonomically. On the basis of morphological, physiological, and chemotaxonomic data, as well as DNA-DNA hybridization data, we propose that 11 of these strains should be classified in the genus Aureobacterium as new combinations or new species, as follows: Aureobacterium esteraromaticum comb. nov. (type strain, IFO 3751 [= ATCC 8091]), Aureobacterium arabinogalactanolyticum sp. nov. (type strain, IFO 14344), Aureobacterium keratanolyticum sp. nov. (type strain, IFO 13309), Aureobacterium luteolum sp. nov. (type strain, IFO 15074 [= DMS 20143]), Aureobacterium schleiferi sp. nov. (type strain, IFO 15075 [= DMS 20489]), Aureobacterium terrae sp. nov. (type strain, IFO 15300), and Aureobacterium trichothecenolyticum sp. nov. (type strain, IFO 15077 [= JCM 1358]). Whereas the peptidoglycan type of members of this genus is considered to be B2beta, the new species A. keratanolyticum was shown to have a new peptidoglycan type, murein variation B2alpha. An emended description of the genus Aureobacterium is presented.

Bacterial Typing Techniques↗
PubMed1993

Nasal melanoma.

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Formaldehyde↗
PubMed1992

[Acute schistosomiasis in travellers to the tropics].

Two of three members (a 29-year-old man [case 1] and a 26-year-old woman [case 2]) of a tourist party to the tropics (Mali) developed a high fever (less than or equal to 40 degrees C), headache, cough, weight loss (less than or equal to 5 kg) and tiredness 3-4 weeks after returning to Germany. In case 1, acute schistosomiasis was tentatively diagnosed as the cause because he reported an attack of dermatitis after exposure to fresh water in an endemic schistosomiasis region and had marked eosinophilia (2118/microliters; 28%) on admission. Serological tests were positive (ELISA with adult antigen, O.D. 0.65 [normal less than 0.15]; with egg antigen O.D. 1.73 [normal less than 0.30], antibody titre in the immunofluorescence test 1:320 [normal less than 1:80]) supported the diagnosis and it was confirmed by demonstrating the parasite, Schistosoma mansoni, in stool but not urine. Findings in case 2 were similar. The third member of the group [case 3], a 58-year-old woman, was symptom-free, but tests revealed schistosomiasis. All three patients were treated with a single dose of Praziquantel (40 mg/kg). A second course of praziquantel (single dose of 40 mg/kg as well as 20 mg/kg three times daily for 3 days) became necessary in case 1, while in case 3 a further single dose of 40 mg/kg was given to ensure a parasite-free state. A follow-up scheme is suggested: clinical examination with white cell and differential counts 1, 3, 6 and 12 months after treatment; three stool and/or urine examinations 3, 6 and 12 months after treatment.

Adult↗
PubMed1992

Enhancement of muscle regeneration in the rat gastrocnemius muscle by low energy laser irradiation.

The effect of low-energy laser (He-Ne) irradiation on the rate of skeletal muscle regeneration after partial excision of the rat gastrocnemius muscle was studied using quantitative histological morphometric methods. The injured zones of the experimental rats were subjected to direct He-Ne laser (632.8 nm wavelength) irradiation (6.0 mW for 2.3 min) immediately following injury and once daily thereafter for 5 days. Muscles that were injured as above and subjected to red or room light irradiation served as a control group. The volume fraction (percent of total volume of injured zone) of the mononucleated cells in the injured zone decreased gradually with time after injury, but more rapidly in the laser irradiated muscles than in the control. At 3 days post-injury the myotubes in the laser-irradiated muscles populated a significantly higher percentage (13.9 +/- 1.1%) of the injured area than in the control muscles (7.8 +/- 1.0%). The volume fraction of the young myofibers in the laser irradiated muscles exceeded 30.6 +/- 2.2% and 49.6 +/- 5.6% at 8 and 11 days post-injury, respectively, while in control muscles these structures comprised only 9.6 +/- 1.0% and 27.2 +/- 3.8% of the injured zone at 8 and 11 days after injury, respectively. It is concluded that He-Ne laser irradiation during the regeneration process promotes muscle maturation in the injured zone following partial excision of the rat gastrocnemius muscle.

Animals↗
PubMed1992

Experimental onchocerciasis in chimpanzees. Antibody response and antigen recognition after primary infection with Onchocerca volvulus.

Nine of 18 chimpanzees inoculated with 250 infective third-stage larvae (L3) each developed patent (i.e., positive for microfilariae) Onchocerca volvulus infection. Four of 6 infected chimpanzees that received 200 micrograms/kg ivermectin at 28 days postinfection (pi) became patent, whereas, when ivermectin was given concurrently with L3 challenge only 1 of 6 infected animals developed patent infection. The antibody response to O. volvulus adult worm-derived antigens (OvAg) showed clear differences between patent and nonpatent chimpanzees. Three months pi, all sera detected several OvAg in the range of M(r) 35-120 k. Sera collected 6 mo pi from later patent animals recognized increasing numbers of OvAg, especially in the lower MW range of M(r) 13 to 33 k. Beginning 10 months pi Onchocerca-antigens of M(r) 21, 24, 26, and 28 k were detected only by patent chimpanzee's sera. The antibody response in nonpatent chimpanzees consistently recognized fewer OvAg, most of which were limited to the higher M(r) range (35-120 k). The reactivity of sera from infected chimpanzees to a low molecular weight fraction (LMW) of total OvAg doubled within 6 months pi, and increased continuously in patent animals from 13 until 30 months pi. Serological reactivity of nonpatent animals to LMW-OvAg remained low. The titers of circulating IgG directed against total OvAg increased in all infected chimpanzees, and continued to rise with patency. In nonpatent chimpanzees the antibody production gradually returned to preinfection values. Total and OvAg-specific IgE increased in patent and nonpatent chimpanzees. Also, during prepatency the granulocyte and antibody-mediated in vitro killing of microfilariae of O. volvulus increased in subsequently patent chimpanzees. The in vitro immobilization of L3 remained low.

Animals↗
PubMed1992

The embryonically active gene, unkempt, of Drosophila encodes a Cys3His finger protein.

The unkempt gene of Drosophila encodes a set of embryonic RNAs, which are abundant during early stages of embryogenesis and are present ubiquitously in most somatic tissues from the syncytial embryo through stage 15 of embryogenesis. Expression of unkempt RNAs becomes restricted predominantly to the central nervous system in stages 16 and early 17. Analysis of cDNAs from this locus reveals the presence of five Cys3His fingers in the protein product. Isolation and analysis of mutations affecting the unkempt gene, including complete deletions of this gene, indicate that there is no zygotic requirement for unkempt during embryogenesis, presumably due to the contribution of maternally supplied RNA, although the gene is essential during post-embryonic development.

Amino Acid Sequence↗
PubMed1992

Phylogenetic evidence for the transfer of Eubacterium suis to the genus Actinomyces as Actinomyces suis comb. nov.

The 16S rRNA primary structures of Eubacterium suis DSM 20639T (T = type strain) and Bifidobacterium bifidum DSM 20456T were determined by sequencing in vitro amplified rDNA. Sequence comparisons indicated that B. bifidum is moderately related to representatives of the genera Actinomyces and Mobiluncus. The closest relative of E. suis is Actinomyces pyogenes. E. suis and A. pyogenes are more closely related phylogenetically to one another than to the other Actinomyces species that have been investigated by using comparative 16S rRNA analysis. Therefore, we propose that E. suis should be transferred to the genus Actinomyces as Actinomyces suis comb. nov.

Actinomyces↗
PubMed1991

An immunogenic Onchocerca volvulus antigen: a specific and early marker of infection.

Onchocerciasis (river blindness) is a serious health problem and a severe obstacle to social and economic development, especially in Africa. A complementary DNA fragment coding for an Onchocerca volvulus antigen (OV-16) was cloned and expressed in the plasmid vector pCG808fx. Immune responses to this O. volvulus-specific recombinant antigen were detectable in patients with documented onchocerciasis; the antibody response was also detectable at 3 months and at more than 1 year before infection could otherwise be detected in humans and in chimpanzees experimentally infected with O. volvulus third-stage larvae.

Animals↗
PubMed1991

Psychrotrophic, lactic acid-producing bacteria from anoxic waters in Ace Lake, Antarctica; Carnobacterium funditum sp. nov. and Carnobacterium alterfunditum sp. nov.

Heterofermentative, lactic acid-producing, gram-positive, motile bacteria were isolated from the waters of Ace Lake, Antarctica. All strains produced virtually only L(+)lactic acid from D(+)glucose. D(--)-ribose was fermented to lactic, acetic, and formic acids, and ethanol. Cell walls contained meso-diaminopimaleic acid. The strains did not grow at 30 degrees C and were psychrotrophic. Whole cells contained 18:1 cis 9 as a major component of their fatty acids. At 20 degrees C, the strains grew better anaerobically than aerobically and all strains lacked catalase, oxidase and respiratory lipoquinones. DNA that coded for most of the 16S rRNA gene of one of the strains was amplified by the polymerase chain reaction and sequenced. The strain was phylogenetically most closely related to Carnobacterium mobile (Knuc = 0.0214). The isolates separated into two phenotypes. DNA/DNA homology studies determined on a representative from each phenotype showed low homology between the phenotypes (38 +/- 8%), and with Carnobacterium mobile (26 +/- 2%, 34 +/- 2%). Carnobacterium funditum sp. nov. produced acid from mannitol, trehalose, but not amygdalin. The G + C content of the DNA was 32-34%, and the Type strain is DSM 5970 (=ACAM 312). Carnobacterium alterfunditum sp. nov. produced acid weakly from amygdalin but not from mannitol trehalose. The G + C content was 33-34%, and the Type strain is DSM 5972 (=ACAM 313).

Anaerobiosis↗