Iridovirus infection in mayfly larvae.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
J Weiser
Publications and source records attributed to J Weiser.
Approximate solvent-accessible surface areas from tetrahedrally directed neighbor densities.
A fast analytical formula (TDND) has been derived for the calculation of approximate atomic and molecular solvent-accessible surface areas (SASA), as well as the first and second derivatives of these quantities with respect to atomic coordinates. Extending the work of Stouten et al. (Molecular Simulation, 1993, Vol. 10, pp. 97-120), as well as our own (Journal of Computational Chemistry, 1999, Vol. 20, pp. 586-596), the method makes use of a Gaussian function to calculate the neighbor density in four tetrahedral directions in three-dimensional space, sometimes twice with different orientations. SASA and first derivatives of the 2366 heavy atoms of penicillopepsin are computed in 0.13 s on an SGI R10000/194 MHz processor. When second derivatives are computed as well, the total time is 0.23 s. This is considerably faster than timings reported previously for other algorithms. Based on a parameterization set of nineteen compounds of different size (11-4346 atoms) and class (organics, proteins, DNA, and various complexes) consisting of a total 23,197 atoms, the method exhibits relative errors in the range 0.2-12.6% for total molecular surface areas and average absolute atomic surface area deviations in the range 1.7 to 3.6 A(2).
Molecular Structure↗
Colonoscopic polypectomy in chronic colitis: conservative management after endoscopic resection of dysplastic polyps.
BACKGROUND & AIMS: Adenomatous polyps are by definition dysplastic and pathologically indistinguishable from the dysplasia-associated lesion or mass (DALM) described in 1981. Yet, adenomatous polyps in noncolitic colons are usually removed definitively endoscopically, whereas DALMs are regarded as harbingers of colon cancer, mandating colectomy. METHODS: Since 1988, all of our patients with chronic ulcerative or Crohn's colitis and dysplastic polyps and no coexistent dysplasia in flat mucosa underwent colonoscopic polypectomy. Biopsy specimens were obtained also adjacent to polypectomy sites, from strictures, and throughout the colon at 10-cm intervals. Follow-up colonoscopies and biopsies were performed within 6 months after polypectomy and yearly thereafter. RESULTS: Colonoscopy in 48 patients with chronic colitis (mean duration, 25.4 years) resected 70 polyps (60 in colitic and 10 in noncolitic mucosa). Polyps were detected on screening colonoscopies (29%) and on surveillance (71%). Pathology was tubular adenoma in all polyps from noncolitic mucosa and low-grade dysplasia (57), high-grade dysplasia (2), or carcinoma (1) in polyps from colitic mucosa. Subsequent colonoscopies (mean follow-up, 4.1 years) revealed additional polyps in 48% but no carcinomas. Surgical resection (6 patients) for recurrent polyps confirmed colonoscopic findings. No dysplasia or cancers in flat mucosa were found at surgery or on follow-up colonoscopies. CONCLUSIONS: In patients with chronic colitis who have no dysplasia in flat mucosa, colonoscopic resection of dysplastic polyps can be performed effectively, just as in noncolitic colons.
Adenoma↗
Characterisation of two putative protein Ser/Thr kinases from actinomycete Streptomyces granaticolor both endowed with different properties.
The structural genes, pkg4 and pkg3, encoding two putative protein serine/threonine kinases in Streptomyces granaticolor, have been cloned and sequenced. The genes were isolated after screening genomic sublibraries with specific probes obtained by PCR amplification of chromosomal DNA using degenerate primers which correspond to amino acid sequences highly conserved in eukaryotic protein Ser/Thr kinases. The sequences of these genes predict polypeptide chains of 761 and 780 amino acids for Pkg4 and Pkg3, respectively. The genes are separated by only 2 bp and therefore probably constitute an operon. pkg4, which is positioned upstream of pkg3, contains a UUALeu codon suggesting a developmental-dependent mode of expression. The amino-terminal half of both proteins clearly shares similarities with the family of protein Ser/Thr kinases. Both proteins studied also possess a region rich in Pro and Ala residues and a repeating motif of 11 amino acid residues, the function of which is unknown, in the carboxy-terminal domain. Expression of pkg4 in Escherichia coli gave rise to two different forms: a soluble protein autophosphorylated at threonine residues and an insoluble form phosphorylated at threonine and serine residues. In contrast, when pkg3 was expressed in E. coli, no autophosphorylation was detected either in vivo or in vitro.
Alkaline Phosphatase↗
Antibiotic resistance gene cassettes derived from the omega interposon for use in E. coli and Streptomyces.
Three antibiotic resistance gene cassettes, derived from the omega interposon (Prentki and Krisch (1984) Gene 29, 303-313) were constructed. These cassettes carry different antibiotic resistance genes, conferring resistance to geneticin, hygromycin or viomycin, flanked by short inverted repeats containing transcription and translation termination signals and synthetic polylinkers. These cassettes were designated omega aac, omega hyg and omega vph. Resistance phenotypes conferred by these constructions are selectable in E. coli and Streptomyces. These cassettes can be used for insertional mutagenesis or for vector construction.
DNA Transposable Elements↗
Ultrastructures of Nosema typographi Weiser 1955 (Microspora: Nosematidae) of the Bark Beetle Ips typographus L. (Coleoptera; Scolytidae)
Explore the source record for details and available documents.
Journal Article↗
The Effect of Bacillus thuringiensis M-exotoxin on Trematode Cercariae
The effect of Bacillus thuringiensis israelensis eluate containing water-soluble exotoxin (M-exotoxin) was observed by its use on cercariae of seven trematode species. To the most sensitive species to the toxic effect of the mentioned toxin belonged schistosome furcocercariae (human species Schistosoma mansoni and avian parasite Trichobilharzia szidati). Under the influence of the toxin, surface syncytial structure (tegument) was separated from underlying tissues, with subsequent disintegration of internal organs connected with disruption of acetabular glands and release of their proteolytic content.
Journal Article↗
Protein profiles of Streptomyces aureofaciens producing tetracyclines: reappraisal of the effect of benzyl thiocyanate.
Cell protein profiles of submerged cultures of Streptomyces aureofaciens cultivated in the absence or presence of 12 microM benzyl thiocyanate (BT) were analyzed by one-dimensional SDS polyacrylamide gel electrophoresis. Substantial increase in the intensity of the 13, 35, 37, 60, and 100 kDa protein bands was observed in cultures treated with BT. Similar increase in the 35, 37, and 60 kDa bands was found in a mutant blocked in the last chlortetracycline biosynthesis step. Effect of BT on the solid medium-grown cultures was also observed, with a more intensive substrate mycelium pigmentation and alteration in the spore size and shape as the most characteristic features. Earlier studies of BT effect involving those on the stimulation of chlortetracycline biosynthesis are summarized and a possible signal-transducing mechanism is discussed from the point of view of adaptation of S. aureofaciens to the uncoupling of oxidative phosphorylation.
Bacterial Proteins↗
Nurses do even more as care changes.
Explore the source record for details and available documents.
Adult↗
In vitro measurement of translation accuracy of ribosomes isolated from streptomycin-resistant mutant of Streptomyces granaticolor.
Accuracy of activity of ribosome isolated from UV-light-induced streptomycin-resistant R-21 mutant of Streptomyces granaticolor was measured in an E. coli-derived system translating poly(U) with a high rate and accuracy. Ribosomes from the R-21 mutant strain were shown to be resistant to streptomycin and about two-fold more accurate than those from the wild type. The mutant strain was found to be resistant to 1000 mg/L streptomycin (Stm) during vegetative growth while it sporulated on agar plates containing only up to 200 mg/L of Stm. The growth rate of the R-21 mutant in complex liquid medium was indistinguishable from that of the wild-type strain.
Drug Resistance, Microbial↗
Effect of Bacillus thuringiensis beta exotoxin on ultrastructures of midgut cells of Culex sitiens.
In midgut cells of Culex sitiens intoxicated with beta exotoxin of Bacillus thuringiensis, the microvilli are greatly reduced. In the cytoplasm there is progressive disarrangement of the membranes of the rough endoplasmic reticulum, first to spherules, and later to a granular mass. Minute vacuoles appearing in the cytoplasm are parts of the distorted labyrinth and remains of the Golgi membranes. There is no disintegration of the outer cell membrane, and no hypertrophy of goblet cells. Nuclei remain in their posterior position and there are no cytoplasmic autophagic vacuoles in the centre. Cells in the same part of the midgut differ in the degree of disorganization.
Adenosine↗
Early experiences with microsporidia of man and mammals.
Comparative data are given of microsporidian infections in insects and mammals. Due to minute size and diffuse distribution in mammals microsporidia were recognized in vertebrates only during search for virus infections. Early infections with Encephalitozoon in rearings of laboratory animals contaminated many isolates of other protozoan infections. Old separate descriptions of microsporidia in mice, rabbits or dogs have to be reevaluated with modern methods of molecular analysis. Old cases of infection of man known now as Encephalitozoon chagasi or Encephalitozoon sp. Matsubayashi are not belonging to the genus Encephalitozoon and should be jointly studied with Nosema connori as eventually identical. With actual improvements of methods of diagnostics the net of detection of microsporidia in man should be extended on routine testing of urine, faecal samples, eye and nose biopsies and other materials including vaginal smears. The way of circulation of the infections in the host organisms must be studied.
Animals↗
Bacillary epithelioid angiomatosis involving the liver, spleen, and skin in an AIDS patient with concurrent Kaposi's sarcoma.
The simultaneous findings of bacillary epithelioid angiomatosis and Kaposi's sarcoma of the skin with visceral hepatosplenic bacillary epithelioid angiomatosis is reported in a patient with acquired immune deficiency syndrome. Liver biopsy showed periportal peliotic spindle cell foci that initially were misinterpreted as Kaposi's sarcoma. After antibiotic therapy induced rapid clinical improvement, repeated liver biopsy showed resolution of the previously noted lesions. Although the violaceous skin lesions all appeared similar clinically, some resolved completely and some progressed. One of the latter was biopsied and had the histologic features of Kaposi's sarcoma. The differential diagnosis is discussed.
Acquired Immunodeficiency Syndrome↗
The mosquitocidal activity of conidia of Tolypocladium tundrense and Tolypocladium terricola.
Tolypocladium tundrense and T. terricola UV-irradiated conidia exhibited acute toxicity to Aedes aegypti larvae in concentrations of 5 x 10(5) and 5 x 10(6) ml-1, respectively. Substances deposited on the surface of conidia following sporulation appear to be responsible for rapid intoxication and killing of mosquito larvae. Treatment of larvae with dried methanolic extract of the spores also induced a high level of mortality accompanied by the same histological changes, including vacuolization and subsequent destruction of mitochondria of the midgut cells. Cyclosporin A was identified as a predominant metabolite forming the spore surface layer.
Aedes↗
Ultrastructural changes in Culex pipiens larvae treated with tolypin, the insecticidal metabolite of Tolypocladium inflatum gams (Deuteromycetes).
Tolypin, the insecticidal metabolite of the entomopathogenic fungus of the genus Tolypocladium, causes knock-down effect followed by high mortality in treated Culex pipiens molestus larvae. Histopathological changes accompanying the knock-down symptoms were similar in all tissues. Mitochondria, the main target in the cells, were destroyed and consecutively changed into vacuoles with the remains of cristae and lysed internal structures. Despite destruction of the internal content of individual organelles, the membranes of the cell surfaces, the endoplasmic reticulum, the nuclei, and the covering membranes of tissues and organs, were not affected and remained intact until final autolysis of the tissues. Some mitochondria in intoxicated cells were destroyed completely, but others remained intact and apparently structurally unchanged.
Animals↗
Characterization of an asporogenous mutant of Streptomyces aureofaciens with increased resistance to several aminoglycoside antibiotics.
An asporogenous spontaneous mutant of Streptomyces aureofaciens named ASR1 was selected on streptomycin gradient plates. The mutant is very stable and differs in ultrastructure and morphology, it is prototrophic but it lost the ability to grow well on soybean extract medium and produces one-tenth tetracyclines of the parent. The ASR1 mutant has a 3-4-fold increased resistance to streptomycin and is cross-resistant to other aminoglycosides. Comparison of the protein profiles from both strains on SDS gels revealed a very low expression of a 29.5 kDa protein in the ASR1 mutant which is overexpressed in both vegetative cells and spores of the parental strain.
Aminoglycosides↗
Coelomomyces irani sp.n. infecting Anopheles maculipennis in Iran.
Explore the source record for details and available documents.
Animals↗
[Epidemiologic data of rupture of the fibular ligament of the upper ankle joint].
Epidemical studies of fibular ligament lesions of the ankle joint lateral ligamentous lesions at the ankle joint are one of the most accidental injuries. It is necessary to bestow great care on prevention and therapy to avoid after effects. We report about 150 cases of acute injuries of the fibular ligament lesions of the ankle joint in 1987 treated by surgery and followed up to explore the cause of injury, its dimensions, the groups of patients and time of accident. Corresponding to literature sports activities were mostly the reason of accidents followed by casional accidents and industrial accidents. Mainly young people suffered from this injury preferring men. The part of reruptures was 14%. In 61.3% both Lig. fibulotal. ant. and Lig. fibulocalc. were ruptured followed by isolated rupture of the Lig. fibulotal.ant. in 32.7% of the cases.
Adolescent↗