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991.
992.
In situ hybridizations were performed on mature human sperm cells with biotin-labeled -satellite DNA probes specific for chromosomes 3, 7, 10, 11, 17, and X in order to reveal the disomy rate for each of these chromosomes. A total of 76 253 sperm nuclei from seven healthy probands aged 23–57 years were analyzed. An average of 12 000 sperm nuclei (at least 1500 per donor) showing hybridization were scored with each probe. The disomy rate as indicated by two distinct hybridization signals turned out to be similar for all chromosomes, ranging from 0.31% to 0.34%. There were no significant interindividual differences and no age correlation in the frequency of disomic sperm cells between the donors. 相似文献
993.
Virginia Morera-Pujol Paulo Catry Maria Magalhães Clara Péron José Manuel Reyes-González José Pedro Granadeiro Teresa Militão Maria P. Dias Daniel Oro Giacomo Dell'Omo Martina Müller Vitor H. Paiva Benjamin Metzger Verónica Neves Joan Navarro Georgios Karris Stavros Xirouchakis Jacopo G. Cecere Antonio Zamora-López Manuela G. Forero Ridha Ouni Mohamed Salah Romdhane Fernanda De Felipe Zuzana Zajková Marta Cruz-Flores David Grémillet Jacob González-Solís Raül Ramos 《Diversity & distributions》2023,29(1):19-38
994.
Del Bianco Chiara Ulivi Martina Liguori Claudio Pisani Antonio Mercuri Nicola Biagio Placidi Fabio Izzi Francesca 《Sleep and biological rhythms》2023,21(1):39-50
Sleep and Biological Rhythms - Non-sleep symptoms, as depression, anxiety and overweight, are often encountered in narcoleptic patients. The purposes of this study are to evaluate mood,... 相似文献
995.
Martina F. Harianja Sarah H. Luke Holly Barclay Vun K. Chey David C. Aldridge William A. Foster Edgar C. Turner 《Entomologia Experimentalis et Applicata》2023,171(2):102-115
Length–biomass equations are relatively easy and cost-effective for deriving insect biomass. However, the exact relationship can vary between taxa and geographical regions. Semi-aquatic bugs are abundant and are indicators of freshwater quality, but there are no studies investigating the effect of habitat disturbance on their biomass, although it is useful in assessing ecological processes. We identified the best-fit length–biomass models to predict the biomass of semi-aquatic bugs (Hemiptera, Gerromorpha) collected from streams in Sabah, Malaysia. We used 259 juvenile and adult semi-aquatic bugs to compare a range of plausible length–biomass functions, and to assess whether relationships differed across the following families and body forms: (1) Cylindrostethinae, Gerrinae, and Ptilomerinae, which are subfamilies within Gerridae consisting of small-to-large bugs that have long and slender bodies, (2) Halobatinae, a subfamily within Gerridae, consisting of small-to-medium bugs with wide heads and thoraxes as well as short abdomens, and (3) Veliidae, which are small bugs with stout bodies. Estimation used five fitting functions – linear regression, polynomial regression order 2, 3, and 4, and power regression – on the following groupings: three body forms combined; each body form with life stages (juvenile and adult) combined; and each body form with life stages separated. Power regressions were the best fit in predicting the biomass of semi-aquatic bugs across life stages and body forms, and the predictive power of models was higher when the biomass of different body forms was calculated separately (specifically for Halobatinae and Veliidae). Splitting by life stages did not always result in additional improvement. The equations from this study expand the scope of possible future ecological research on semi-aquatic bugs, particularly in Southeast Asia, by allowing more studies to consider biomass-related questions. 相似文献
996.
Pfeifer Karin; Haasemann Martina; Gamulin Vera; Bretting Hagen; Fahrenholz Falk; Mller Werner E.G. 《Glycobiology》1993,3(2):179-184
The marine sponge Geodia cydonium contains several lectins.The main component, called lectin-1, is composed of three tofour identical subunits. The subunits of the lectins were clonedfrom a cDNA library; two clones were obtained. From the deducedaa sequence of one clone, LECT-1, a mol. wt of 15 313 Da iscalculated; this value is in good agreement with mass spectrometricanalysis of 15 453 25 Da. The sequence of another clone, LECT-2,was analysed and the aa sequence was deduced (15 433 Da). Thetwo subunits have a framework sequence of 38 conserved aa whichare characteristic for the carbohydrate-binding site of vertebrateS-type lectins. Clustering of lectin sequences of various speciesfollowing their pairwise comparison establishes a dendrogram,which reveals that the sponge lectin could be considered asthe ancestor for vertebrate S-type lectins. Geodia cydonium lectin sponges S-type lectin 相似文献
997.
The anaerobic hyperthermophilic archaea Desulfurococcus amylolyticus, Hyperthermus butylicus, Thermococcus celer, Pyrococcus woesei, the hyperthermophilic bacteria Thermotoga maritima and Clostridium thermohydrosulfuricum and the aerobic mesophilic archaeon Halobacterium saccharovorum were grown either on complex media, on sugars or on pyruvate as carbon and energy sources. During growth acetate was formed as fermentation product by all organisms. The enzymes involved in acetyl-CoA formation from pyruvate and in acetate formation from acetyl-CoA were investigated:
- Cell extracts of all species, both archaea and bacteria, catalyzed the coenzyme A-dependent oxidative decarboxylation of pyruvate with viologen dyes or with Clostridium pasteurianum ferredoxin as electron acceptors indicating a pyruvate: ferredoxin oxidoreductase to be operative in acetyl-CoA formation from pyruvate.
- Cell extracts of all archaeal species, both hyperthermophiles (D. amylolyticus, H. butylicus, T. celer, P. woesei) and the mesophile H. saccharovorum, contained an acetyl-CoA synthetase (ADP forming), which catalyzes both acetate formation from acetyl-CoA and ATP synthesis from ADP and phosphate (Pi): Acetyl-CoA+ADP+Pi?Acetate + ATP+CoA. Phosphate acetyltransferase and acetate kinase could not be detected.
- Cell extracts of the hyperthermophilic (eu)bacteria T. maritima and C. thermohydrosulfuricum contained phosphate acetyltransferase and acetate kinase rather than acetyl-CoA synthetase (ADP forming).
998.
Carola Hunte Martina Janßen Margot Schulz O. Traub K. Willecke Heide Schnabl 《Plant biology (Stuttgart, Germany)》1993,106(3):207-212
A strong age dependency together with alterations in the cellular distribution of CX 26 immunorelated protein(s) was found for differently developed leaves of Vicia faba L. With increasing age, an immunoreactive 40 kD band was observed in the soluble and microsomal fraction. In the cell wall protein preparation of young and fully differentiated leaves the 40 kD band was the minor constituent. A 33 kD polypeptide was dominantly localized in the microsomal fractions of all developmental stages and in SDS-extracts of total cell proteins of young leaves. A 21 kD protein together with a 16 kD polypeptide was associated with the cell wall fraction. The 21 kD protein, assumed to represent a plasmodesmatal constituent, was reduced with age. In SDS extracts, prepared from the different developmental stages of the leaves and of mesophyll protoplasts, the age-dependent appearance of the several immunostained bands was most obvious. A correlation of the 16, 33, and 40 kD bands to a turnover of the 21 kD protein is suggested. The reduced amount of the 21 kD protein with increasing age may be contemplated as an indication for a relative decrease of symplastic connections between cells of maturing leaves. This is in agreement with the results obtained by immunofluorescence studies using guard cell protoplasts. Here, observations pointed also to a reduction and final loss of CX 26-related protein at the protoplast surfaces. 相似文献
999.
Liliana S. Celaya María A. Le Vraux Cecilia I. Heit Carmen I. Viturro Pablo F. Martina 《化学与生物多样性》2023,20(6):e202201105
The purpose of this study was to investigate essential oils (EOs) from leaves of Elionurus muticus growing in Northeastern Argentina regarding their physicochemical profiles as well as their biological potential. Roots of a selected E. muticus population were investigated too. For this purpose, EOs of fresh materials were obtained by steam distillation and the chemical composition was characterized by gas chromatography GC/MS-FID. Antibacterial, antioxidant and eco-toxicity activities of the essential oils (EOs) were tested by in vitro assays. The EOs showed three E. muticus chemotypes: citral (neral+geranial), acorenone+bisabolone, acorenone+geranial. EO of roots of citral population contains mainly acorenone derivatives. EOs have high antibacterial effect against Staphylococcus aureus, being found minor antibacterial effect against Gram-negative bacteria. The half-maximal inhibitory concentration of EOs against DPPH⋅ were 7.1–30.0 mg/mL and the eco-toxicity was high with LD50 <39 μg/mL. Based on the findings, given the high variability in their chemical composition and biological activity of E. muticus EO and the promising yields, it could be potentially chosen for industrial applications. 相似文献
1000.
Binding of vitronectin and plasminogen to Helicobacter pylori 总被引:2,自引:0,他引:2
Martina Ringnér Kaija H. Valkonen Torkel Wadström 《FEMS immunology and medical microbiology》1994,9(1):29-34
Abstract We have studied how some extracellular matrix proteins, fibronectin, fibrinogen, collagen type I and type IV, plasminogen and vitronectin bind to Helicobacter pylori . Radiolabelled vitronectin and plasminogen bound to the haemagglutinating H. pylori strain 17874 at a high level (53% and 32%, respectively), type IV collagen showed an intermediate level of binding (16%), while binding by 125 I-labelled fibrinogen, fibronectin and collagen type I remained at a low level (5–7%). Both 125 I-vitronectin and plasminogen showed a dose-dependent binding to cells of H. pylori 17874. Plasminogen binding by this strain was specific since the binding was inhibited by nonlabelled plasminogen, but not by highly glycosylated glycoproteins such as fetuin and orosomucoid or by a variety of monosaccharides. We have previously shown that 125 I-vitronectin shows a specific and saturable binding to H. pylori 17874, and that sialic acid-rich glycoproteins such as fetuin and orosomucoid drastically reduced binding. We now report that a simultaneous incubation of 125 I-vitronectin and 125 I-plasminogen with cells of H. pylori 17874 showed a total binding approximately similar to the level of binding when either 125 I-plasminogen, or 125 I-vitronectin only were incubated with the bacterial cells. Nonlabelled vitronectin inhibited the binding of 125 I-plasminogen by H. pylori , but nonlabelled plasminogen had no effect on the binding of 125 I-vitronectin. Our findings suggest that there are different but probably closely localized binding sites for vitronectin and plasminogen on H. pylori 17874. 相似文献