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21.
Douglas L. Currell Bernice Law Michael Stevens Paul Murata Carmela Ioppolo Filippo Martini 《Biochemical and biophysical research communications》1981,102(1):348-354
Human hemoglobin reacts with 4-Isothiocyanatobenzene sulfonic acid at the four amino groups of the N-terminal valines. The modified protein shows a decreased oxygen affinity over a wide pH range, a reduced alkaline Bohr effect, decreased co-operativity, and a reduced effect of inositol hexasulfate on the oxygen affinity. 相似文献
22.
A C Fusco 《Experimental parasitology》1978,44(2):155-160
The hemoglobins of Spirocamallanus cricotus, a reddish-colored, camallanid nematode, and its Atlantic croacker fish host, Micropogonias undulatus, were characterized with spectrophotometry and isoelectric focusing. Hemoglobin from female parasites' perienteric fluid and homogenized male parasites gave Spectrophotometric peaks at 412, 539, and 575 nm, whereas female worms drained of perienteric fluid and homogenized differed by having a Soret peak of 408 nm. Changing the ionic strength of the buffer from 0.1 to 0.01 M shifted the Soret peak to 406 nm for the female parasites' perienteric fluid and ground male parasites and 404 nm for homogenized female parasites. In all cases, the β band had a higher absorption than the α band suggesting a high O2 affinity for the parasite hemoglobin. Host hemoglobin had peaks of 406, 437, and 577 nm. Isoelectric focusing not only confirmed the Spectrophotometric evidence that host and parasite hemoglobins differed, but also showed that the parasite's analyzed hemoglobin fractions differed from one another by having different isoelectric points. 相似文献
23.
24.
Girolamo A. Vitello Francesco Calì Mirella Vinci Carmela Scuderi Francesca LEpiscopo Antonino Musumeci Sebastiano A. Musumeci Antonio G. Nicotera 《Journal of musculoskeletal & neuronal interactions》2020,20(4):610
Spinal muscular atrophy (SMA) refers to a group of genetic neuromuscular disorders affecting lower motor neurons causative of numerous phenotypes. To date, according to the age of onset, maximum muscular activity achieved, and life expectation four types of SMA are recognized, all caused by mutations in the SMN1 gene with SMN2 copy number influencing disease severity. Herein, we describe the case of a 31-year-old young male with normal psychomotor development who has experienced fatigue, cramps, and muscle fasciculations in the lower limbs for a period of 2 months. Based on electrophysiological and clinical findings we performed SMA genetic, clinical exome and RNA expression of candidate genes which led us to suggest SMN1-SMN2 genes [(2+0) and (0+0)] combination as possibly being implicated in the phenotype. 相似文献
25.
Ana Roberta Fusco da Costa Joseph O. Falkinham III Maria Luiza Lopes Adriana Rodrigues Barretto Jo?o Soares Felicio Lúcia Helena Messias Sales Jeann Ricardo da Costa Bahia Emilyn Costa Concei??o Karla Valéria Batista Lima 《PLoS neglected tropical diseases》2013,7(7)
The majority of investigations of the epidemiology of nontuberculous mycobacteria (NTM) have focused on highly developed nations with a low prevalence of tuberculosis. In contrast, the Para state of north Brazil represents an area of high tuberculosis prevalence and increasing NTM incidence. Toward the goal of understanding the dynamics of infection by all Mycobacterium species, we report patient characteristics and the identification of NTM strains isolated from sputum samples from patients that were residents of Para, a state in the Amazon region, Northern of Brazil, over the period January 2010 through December 2011 (2 years). The 29 NTM patients comprised 13.5% of positive mycobacterial cultures over the 2-year period. A major risk factor for NTM pulmonary disease was previous tuberculosis (76%). Further, the average age of NTM patients (52 years) was significantly higher than that of tuberculosis patients (39 years) and more were female (72.4% vs. 37.4%). Unlike other Brazilian states, NTM pulmonary patients in Para were infected with a different spectrum of mycobacteria; primarily the rapidly growing Mycobacterium massiliense and Mycobacterium simiae complex. 相似文献
26.
Melania Manco Maria Rita Spreghini Rosa Luciano Cecilia Pensini Rita Wietrzycowska Sforza Carmela Rustico Marco Cappa Giuseppe Stefano Morino 《PloS one》2013,8(7)
Background
Insulin sensitivity decreases at puberty transition, but little information has been provided on its earlier time-course. Aim of the present study was to describe the time-course of insulin sensitivity in severely obese children at the transition from preschool to school age.Research design and methods
Retrospective study of a cohort of 47 severely obese [Body Mass Index (BMI) ≥99° percentile] preschoolers evaluated twice, once between 2 and 6 years of age, and once before age 8. Glucose tolerance, Whole Body Insulin Sensitivity Index (WBISI), Insulinogenic Index (IGI); β-cell demand index (BCDI) and Insulin Secretion-Sensitivity Index 2 (ISSI-2) were longitudinally estimated during the oral glucose tolerance test.Results
After a median follow-up of 2.23 (1–4.52) y, obese patients showed significant decrease in WBISI (p<0.0001), and increase in fasting (p = 0.005) and 2 h glucose (2HG, p = 0.001). One child in preschool age and 4 school age children presented with 2HG between 7.8–11.1 mmol/l. Best predictors of WBISI, 2HG and BCDI in the school age were changes in BMI z-score (R2 = 0.309; p = 0.002; β = −0.556), ISSI-2 (R2 = 0.465; p<0.0001; β = −0.682), and BMI z-score (R2 = 0.246; p = 0.008; 0.496), respectively.Conclusions
In morbidly obese children, insulin sensitivity seems to decline even before pubertal transition, but changes in total adiposity can only partially explain this variation. 相似文献27.
Kai Xu Barry Rockx Yihu Xie Blair L. DeBuysscher Deborah L. Fusco Zhongyu Zhu Yee-Peng Chan Yan Xu Truong Luu Regina Z. Cer Heinz Feldmann Vishwesh Mokashi Dimiter S. Dimitrov Kimberly A. Bishop-Lilly Christopher C. Broder Dimitar B. Nikolov 《PLoS pathogens》2013,9(10)
The henipaviruses, represented by Hendra (HeV) and Nipah (NiV) viruses are highly pathogenic zoonotic paramyxoviruses with uniquely broad host tropisms responsible for repeated outbreaks in Australia, Southeast Asia, India and Bangladesh. The high morbidity and mortality rates associated with infection and lack of licensed antiviral therapies make the henipaviruses a potential biological threat to humans and livestock. Henipavirus entry is initiated by the attachment of the G envelope glycoprotein to host cell membrane receptors. Previously, henipavirus-neutralizing human monoclonal antibodies (hmAb) have been isolated using the HeV-G glycoprotein and a human naïve antibody library. One cross-reactive and receptor-blocking hmAb (m102.4) was recently demonstrated to be an effective post-exposure therapy in two animal models of NiV and HeV infection, has been used in several people on a compassionate use basis, and is currently in development for use in humans. Here, we report the crystal structure of the complex of HeV-G with m102.3, an m102.4 derivative, and describe NiV and HeV escape mutants. This structure provides detailed insight into the mechanism of HeV and NiV neutralization by m102.4, and serves as a blueprint for further optimization of m102.4 as a therapeutic agent and for the development of entry inhibitors and vaccines. 相似文献
28.
Giuseppe Ferrara Andrea Mazzeo Angela Maria Stella Matarrese Carmela Pacucci Andrea Pacifico Giuseppe Gambacorta Michele Faccia Antonio Trani Vito Gallo Isabella Cafagna Piero Mastrorilli 《Journal of Plant Growth Regulation》2013,32(3):491-505
‘Crimson Seedless’ is a table grape cultivar that often fails to develop adequate red color in Mediterranean climates. Application of abscisic acid (S-ABA) may be an aid for improving color, but its potential effects on overall quality and S-ABA concentration of the berry should be also considered. We tested two concentrations (200 and 400 mg/L) and different times of application (from 1 week after veraison up to 9 days before harvest) of a commercial formulation of S-ABA (ProTone®) to verify the effect on harvestable bunches, color, chemical characteristics, metabolic profile, and S-ABA concentration in the berry. It was found that either the application of S-ABA at 400 mg/L one week after veraison or the application of S-ABA at 400 mg/L one week and four weeks after veraison positively affected the berry skin color, shifting the hue (h°) from 20 to a more red-violet hue (h° = 11–12). In general, the application of S-ABA, with the exception of the late treatments, enhanced coloration of the berries and increased the amount of harvestable bunches at the first pick because it promoted the skin-coloring process. S-ABA did not affect berry firmness but reduced the berry detachment force. Nevertheless, the values remained sufficiently high and the general quality of the bunch was not compromised. Ripening parameters (°Brix, pH, titratable acidity) were not affected by S-ABA applications, and even the primary metabolite profile was not influenced by the treatments as ascertained by multivariate statistical analyses [principal component analyses (PCA) and partial least squares discriminant analysis (PLS-DA)] applied to nuclear magnetic resonance (NMR) data. The S-ABA concentration in the berry, when treatments were performed around veraison, was within the natural range for grape (10–400 ng/g f.w.), whereas when late treatments were applied (few days before harvest), the concentration was higher (more than 1,000 ng/g f.w.). The best results for yield, quality, and S-ABA concentration in the berry were observed for the treatments performed a few days after veraison at the dose of 400 mg/L. This study gives new information about the positive effects of S-ABA on color without any particular change in the metabolic profile of the berry. 相似文献
29.
Cristina Becerra-Castro Petra Kidd Melanie Kuffner ángeles Prieto-Fernández Stephan Hann Carmela Monterroso Angela Sessitsch Walter Wenzel Markus Puschenreiter 《Applied and environmental microbiology》2013,79(17):5094-5103
The bioavailability of metals in soil is often cited as a limiting factor of phytoextraction (or phytomining). Bacterial metabolites, such as organic acids, siderophores, or biosurfactants, have been shown to mobilize metals, and their use to improve metal extraction has been proposed. In this study, the weathering capacities of, and Ni mobilization by, bacterial strains were evaluated. Minimal medium containing ground ultramafic rock was inoculated with either of two Arthrobacter strains: LA44 (indole acetic acid [IAA] producer) or SBA82 (siderophore producer, PO4 solubilizer, and IAA producer). Trace elements and organic compounds were determined in aliquots taken at different time intervals after inoculation. Trace metal fractionation was carried out on the remaining rock at the end of the experiment. The results suggest that the strains act upon different mineral phases. LA44 is a more efficient Ni mobilizer, apparently solubilizing Ni associated with Mn oxides, and this appeared to be related to oxalate production. SBA82 also leads to release of Ni and Mn, albeit to a much lower extent. In this case, the concurrent mobilization of Fe and Si indicates preferential weathering of Fe oxides and serpentine minerals, possibly related to the siderophore production capacity of the strain. The same bacterial strains were tested in a soil-plant system: the Ni hyperaccumulator Alyssum serpyllifolium subsp. malacitanum was grown in ultramafic soil in a rhizobox system and inoculated with each bacterial strain. At harvest, biomass production and shoot Ni concentrations were higher in plants from inoculated pots than from noninoculated pots. Ni yield was significantly enhanced in plants inoculated with LA44. These results suggest that Ni-mobilizing inoculants could be useful for improving Ni uptake by hyperaccumulator plants. 相似文献
30.
Laura?Quotti Tubi Carmela?GurrieriEmail author Alessandra?Brancalion Laura?Bonaldi Roberta?Bertorelle Sabrina?Manni Laura?Pavan Federica?Lessi Renato?Zambello Livio?Trentin Fausto?Adami Maria?Ruzzene Lorenzo?A?Pinna Gianpietro?SemenzatoEmail author Francesco?Piazza 《Journal of hematology & oncology》2013,6(1):78