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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 3286-3289, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31946585

ABSTRACT

Despite the growing use of different wearable inertial systems, increasingly diffused in clinical practice, there is still a lack of knowledge about the agreement between systems based also on different sensor configuration. Aim of the study has been the investigation of the agreement between Opal and G-Walk wearable inertial systems in gait analysis on normal and post stroke subjects. Although both systems are able to describe significant gait differences in the two populations, study results suggest that gait analysis evaluations carried out by different inertial systems does not give completely overlapping estimation about the different parameters and that this must be taken in correct account especially comparing results of clinical trials obtained by different systems and sensor's placements.


Subject(s)
Gait Analysis , Stroke , Wearable Electronic Devices , Gait , Humans , Stroke/complications , Walking
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 17498-1752, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31947502

ABSTRACT

The aim of this work is to design and develop a sensorized sock in Electronic Textile (ET), SWEET-Sock. The device has been realized by three textile sensor placed in a specific points of plantar arch and an accelerometer unit, both embedded and connected by conductive thread. The sensors allows the acquisition of plantar pressure and acceleration signals deriving from the motion of the lower limbs. The detected biosignals have been condictionated by a voltage divider and then were acquired through a LilyPad Arduino microcontroller and transmitted using the Simblee BLE technology to a custom made mobile app. Data were afterwards uploaded through a smartphone on a dropbox cloud where a custom made MATLAB GUI platform has been developed for further digital signal processing of main biomechanical parameters of clinical interest in postural and gait analysis.


Subject(s)
Mobile Applications , Smartphone , Textiles , Wearable Electronic Devices , Acceleration , Foot , Gait Analysis , Humans , Posture , Signal Processing, Computer-Assisted
3.
Mycotoxin Res ; 34(2): 107-116, 2018 May.
Article in English | MEDLINE | ID: mdl-29299825

ABSTRACT

Fungi have a crucial role in the correct maturation of salami, but special attention should be addressed to the production of the nephrotoxic, immunotoxic, and carcinogenic mycotoxin ochratoxin A (OTA). In a monitoring study conducted in Northern Italy, OTA was detected by liquid chromatography coupled with mass spectrometry in 13 out 133 samples of traditional salami (9.8% of the total count). Mycological analysis of these samples yielded 247 fungal isolates which were identified to species level. The most frequent species were Penicillium nalgiovense, P. solitum, and P. chrysogenum. P. nordicum, an OTA-producing species commonly found in proteinaceous food, was not found in these samples. Three isolates were found to be Aspergillus westerdijkiae, an OTA-producing species. In order to check the results of the microbiological identification, 19 different strains of Aspergillus and 94 of Penicillium were tested for the presence of a sequence common to OTA-producing fungi by real-time PCR. None of the studied isolates, including the three A. westerdijkiae, possessed the otanpsPN target which is common to OTA-producing strains. Two out of three isolates of the A. westerdijkiae were also PCR-negative for the otanpsPN gene and did not produce OTA in culture. Conversely, this target sequence was amplified from the DNA purified from 14 salami casings including three casings harboring A. westerdijkiae. The amplification of sequences specific for OTA-producing strains performed on total genomic DNA extracted directly from salami casings provided a more suitable approach than PCR analysis of isolates from salami for the OTA-related otanpsPN gene to evaluate the risk of OTA contamination.


Subject(s)
Food Analysis , Food Contamination , Food Microbiology , Fungi/metabolism , Ochratoxins/analysis , Chromatography, Liquid , DNA, Ribosomal Spacer , Food Analysis/methods , Fungi/classification , Fungi/genetics , Fungi/isolation & purification , Italy , Microbiota , Mycotoxins/analysis , Mycotoxins/biosynthesis , Mycotoxins/genetics , Ochratoxins/biosynthesis , Penicillium/classification , Penicillium/genetics , Penicillium/isolation & purification , Penicillium/metabolism , Polymerase Chain Reaction , Tandem Mass Spectrometry
4.
Bone Marrow Transplant ; 52(1): 114-119, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27668762

ABSTRACT

Carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) infections are an emerging cause of death after hematopoietic stem cell transplantation (HSCT). In allogeneic transplants, mortality rate may rise up to 60%. We retrospectively evaluated 540 patients receiving a transplant from an auto- or an allogeneic source between January 2011 and October 2015. After an Institutional increase in the prevalence of KPC-Kp bloodstream infections (BSI) in June 2012, from July 2012, 366 consecutive patients received the following preventive measures: (i) weekly rectal swabs for surveillance; (ii) contact precautions in carriers (iii) early-targeted therapy in neutropenic febrile carriers. Molecular typing identified KPC-Kp clone ST512 as the main clone responsible for colonization, BSI and outbreaks. After the introduction of these preventive measures, the cumulative incidence of KPC-Kp BSI (P=0.01) and septic shocks (P=0.01) at 1 year after HSCT was significantly reduced. KPC-Kp infection-mortality dropped from 62.5% (pre-intervention) to 16.6% (post-intervention). Day 100 transplant-related mortality and KPC-Kp infection-related mortality after allogeneic HSCT were reduced from 22% to 10% (P=0.001) and from 4% to 1% (P=0.04), respectively. None of the pre-HSCT carriers was excluded from transplant. These results suggest that active surveillance, contact precautions and early-targeted therapies, may efficiently control KPC-Kp spread and related mortality even after allogeneic HSCT.


Subject(s)
Bacterial Proteins/biosynthesis , Hematologic Neoplasms , Hematopoietic Stem Cell Transplantation , Klebsiella Infections , Klebsiella pneumoniae , Shock, Septic , beta-Lactamases/biosynthesis , Adolescent , Adult , Aged , Allografts , Autografts , Female , Follow-Up Studies , Hematologic Neoplasms/mortality , Hematologic Neoplasms/therapy , Humans , Klebsiella Infections/genetics , Klebsiella Infections/mortality , Klebsiella Infections/therapy , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/metabolism , Klebsiella pneumoniae/pathogenicity , Male , Middle Aged , Shock, Septic/genetics , Shock, Septic/mortality , Shock, Septic/therapy
5.
Article in English | MEDLINE | ID: mdl-25207983

ABSTRACT

A chromatographic method is proposed for the analysis of aflatoxin B1 in cereal-based feed, particularly targeted to dairy animals. The method is based on a solid-liquid extraction followed by a Mycosep 226 clean-up. Accuracy and precision were established at the LOQ (1 µg kg⁻¹) with a spiked sample as well as with two other different naturally contaminated reference materials. The mean overall recovery (n = 18) was 100.8%, with a confidence interval of 2.7% and a CV% of 5.5%. The performance of the proposed method was compared with the AOAC method based on the use of immunoaffinity chromatography columns, proving that it could be considered a valid alternative. Moreover, the sample preparation is very simple and straightforward, potentially being applicable as a high-throughput method. On account of its simplicity and low cost, the method may be applied to the analysis of a large number of samples in the occasion of outbreaks of large-scale contamination.


Subject(s)
Aflatoxin B1/analysis , Animal Feed/analysis , Carcinogens, Environmental/analysis , Edible Grain/chemistry , Food Contamination , Food Inspection/methods , Aflatoxin B1/chemistry , Analytic Sample Preparation Methods , Animal Feed/standards , Calibration , Carcinogens, Environmental/chemistry , Chromatography, High Pressure Liquid , European Union , Italy , Limit of Detection , Molecular Structure , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry
6.
Phys Chem Chem Phys ; 16(37): 20061-72, 2014 Oct 07.
Article in English | MEDLINE | ID: mdl-25130260

ABSTRACT

Thioflavin-T (TFT) is a fluorescent marker widely employed in biomedical research but the mechanism of its binding to polynucleotides has been poorly understood. This paper presents a study of the mechanisms of TFT self-aggregation and binding to DNA. Relaxation kinetics of TFT solutions show that the cyanine undergoes dimerization followed by dimer isomerisation. The interaction of TFT with DNA has been investigated using static methods, such as spectrophotometric and spectrofluorometric titrations under different conditions (salt content, temperature), fluorescence quenching, viscometric experiments and the T-jump relaxation method. The combined use of these techniques enabled us to show that the TFT monomer undergoes intercalation between the DNA base pairs and external binding according to a branched mechanism. Moreover, it has also been observed that, under dye excess conditions, the TFT dimer binds to the DNA grooves. The molecular structures of intercalated TFT and the groove-bound TFT dimer are obtained by performing QM/MM MD simulations.


Subject(s)
DNA/chemistry , Thiazoles/chemistry , Benzothiazoles , DNA/metabolism , Dimerization , Kinetics , Molecular Dynamics Simulation , Quantum Theory , Spectrophotometry , Temperature , Thiazoles/metabolism , Viscosity
7.
Int J Comput Assist Radiol Surg ; 9(2): 221-9, 2014 Mar.
Article in English | MEDLINE | ID: mdl-23877281

ABSTRACT

PURPOSE: Image noise in computed tomography (CT) images may have significant local variation due to tissue properties, dose, and location of the X-ray source. We developed and tested an automated tissue-based estimator method for estimating local noise in CT images. METHOD: An automated TBE method for estimating the local noise in CT image in 3 steps was developed: (1) Partition the image into homogeneous and transition regions, (2) For each pixel in the homogeneous regions, compute the standard deviation in a 15 x 15 x 1 voxel local region using only pixels from the same homogeneous region, and (3) Interpolate the noise estimate from the homogeneous regions in the transition regions. Noise-aware fat segmentation was implemented. Experiments were conducted on the anthropomorphic phantom and in vivo low-dose chest CT scans to validate the TBE, characterize the magnitude of local noise variation, and determine the sensitivity of noise estimates to the size of the region in which noise is computed. The TBE was tested on all scans from the Early Lung Cancer Action Program public database. The TBE was evaluated quantitatively on the phantom data and qualitatively on the in vivo data. RESULTS: The results show that noise can vary locally by over 200 Hounsfield units on low-dose in vivo chest CT scans and that the TBE can characterize these noise variations within 5 %. The new fat segmentation algorithm successfully improved segmentation on all 50 scans tested. CONCLUSION: The TBE provides a means to estimate noise for image quality monitoring, optimization of denoising algorithms, and improvement of segmentation algorithms. The TBE was shown to accurately characterize the large local noise variations that occur due to changes in material, dose, and X-ray source location.


Subject(s)
Algorithms , Phantoms, Imaging , Radiography, Thoracic/methods , Tomography, X-Ray Computed/methods , Humans , Radiation Dosage , Reproducibility of Results , Signal-To-Noise Ratio
8.
Article in English | MEDLINE | ID: mdl-23176386

ABSTRACT

A new chromatographic method is proposed for the analysis of aflatoxin M(1) in milk. The method is based on liquid-liquid extraction followed by LC-MS/MS analysis. Liquid-liquid extraction (LLE) is performed on the defatted milk plus sodium chloride by using ethyl acetate as an extraction solvent. Accuracy and precision were evaluated at the LOQ (15 ng kg(-1)) spiked sample as well as with three other different naturally contaminated reference materials. The mean overall recovery (n = 24) was 95% with a confidence interval of 1.9% and a CV% of 4.5%. The performance of the proposed method was compared with that of the Official ISO Method based on the use of immunoaffinity chromatography columns (IAC): LLE protocol could be considered a valid alternative to the LC-IAC. In general it showed better accuracy with lower data dispersion. Moreover, the sample preparation is very simple and straightforward, potentially being applicable as a high-throughput method which, on account of its simplicity and low cost, may be applied to the analysis of a large number of samples in the occasion of outbreaks of large-scale contamination.


Subject(s)
Aflatoxin M1/analysis , Chromatography, Liquid/methods , Food Contamination/analysis , Milk/chemistry , Tandem Mass Spectrometry/methods , Animals , Humans , Spectrometry, Mass, Electrospray Ionization
9.
Metab Brain Dis ; 25(1): 115-24, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20204483

ABSTRACT

Neurological complications are common after liver transplantation (LT) and they are associated with a significant morbidity. Long-term effects of LT on cognitive and psychological outcomes are not clear. The objective of this study was to summarize the present knowledge on the neurological and cognitive complications of LT, resulting from a systematic review of the literature in the last 10 years. Several studies have investigated the incidence and the pathophysiology of neurological complications; in contrast, the knowledge of cognitive and psychological status after LT is poor. Currently, the effect of LT on mental performance is debated. Some studies have shown an improvement of cognitive function after OLTX and, at the same time, a persistence of different cognitive deficits. In addition, the quality of life (QoL) and the psychological status after LT seem to improve but LT recipients have significant deficiencies in most QoL domains. Consequently, future studies are necessary in order to investigate cognitive alterations and QoL in LT recipients.


Subject(s)
Cognition Disorders/physiopathology , Hepatic Encephalopathy/physiopathology , Liver Failure, Acute/surgery , Liver Transplantation/adverse effects , Postoperative Complications/physiopathology , Brain/metabolism , Brain/physiopathology , Cognition/physiology , Cognition Disorders/etiology , Cognition Disorders/metabolism , Hepatic Encephalopathy/etiology , Hepatic Encephalopathy/metabolism , Humans , Immunosuppressive Agents/adverse effects , Liver Transplantation/statistics & numerical data , Postoperative Complications/etiology , Quality of Life , Recurrence , Risk Factors
10.
Article in English | MEDLINE | ID: mdl-19965010

ABSTRACT

The Public Lung Database to address drug response (PLD) has been developed to support research in computer aided diagnosis (CAD). Originally established for applications involving the characterization of pulmonary nodules, the PLD has been augmented to provide initial datasets for CAD research of other diseases. In general, the best performance for a CAD system is achieved when it is trained with a large amount of well documented data. Such training databases are very expensive to create and their lack of general availability limits the targets that can be considered for CAD applications and hampers development of the CAD field. The approach taken with the PLD has been to make available small datasets together with both manual and automated documentation. Furthermore, datasets with special properties are provided either to span the range of task complexity or to provide small change repeat images for direct calibration and evaluation of CAD systems. This resource offers a starting point for other research groups wishing to pursue CAD research in new directions. It also provides an on-line reference for better defining the issues relating to specific CAD tasks.


Subject(s)
Databases, Factual , Diagnosis, Computer-Assisted/instrumentation , Diagnosis, Computer-Assisted/methods , Emphysema/diagnosis , Solitary Pulmonary Nodule/diagnosis , Access to Information , Calibration , Computer Graphics , Computers , Emphysema/diagnostic imaging , Humans , Radiographic Image Interpretation, Computer-Assisted/methods , Reproducibility of Results , Software , Solitary Pulmonary Nodule/diagnostic imaging , Tomography, X-Ray Computed/methods
11.
Anal Chim Acta ; 617(1-2): 132-8, 2008 Jun 09.
Article in English | MEDLINE | ID: mdl-18486648

ABSTRACT

A fast, simple and very selective liquid chromatography-mass spectrometry (LC-MS) method for the detection of isopropylthioxanthone (ITX) in dairy products has been developed and validated. After addition of an ITX-d(3) as internal standard and a simple extraction from the sample with acetonitrile, the extract was centrifuged and directly injected into the LC-MS system. Chromatographic separation was achieved by means of a Gemini C18 column (100 mm x 2.0 mm i.d. 5 microm) using a gradient of aqueous 20 mM ammonium formiate at pH 4.5 and methanol as the mobile phase, at a flow rate of 0.25 mL min(-1). The method was validated according to the guidelines laid down by the Commission Decision 2002/657/EC using the parent ion [M+H](+) (m/z 255) as quantification ion, and the fragment ion (m/z 213) obtained by in-source collision-induced dissociation (IS-CID) as confirmation ion. Absolute and relative recoveries rates were verified at 5, 10, 15 microg kg(-1) in yoghurt samples and at 5 microg kg(-1) in milk and pudding: mean absolute recoveries were 77% in yoghurt, 50% in pudding and 67% in milk; relative recoveries (after internal standard correction) were always >97% in each matrix. The detection limit (CCalpha) and the detection capability (CCbeta) of method were 6.2 and 7.2 microg kg(-1), respectively.

13.
Dig Liver Dis ; 39(8): 740-7, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17611177

ABSTRACT

BACKGROUND: The number of orthotopic liver transplantation performed each year is increasing due to increased safety and logistic facilities. Therefore, the importance of reducing adverse events is progressively growing. AIM: To review present knowledge on the neurological complications of orthotopic liver transplantation. METHODS: The epidemiology, the clinical features and the pathophysiology of the neurological complications of orthotopic liver transplants, resulting from a systematic review of the literature in the last 25 years, are summarized. RESULTS AND CONCLUSIONS: The review highlights that a relevant variety of neurological adverse events can occur in patients undergoing orthotopic liver transplantation. The knowledge of neurological complications of orthotopic liver transplantation is important for transplantation teams to reduce their prevalence and improve their management. In addition, the likelihood of neurological adverse effects provides evidence for the need of a careful cognitive and neurological work up of patients in the orthotopic liver transplantation waiting list, in order to recognize and interpret neurological dysfunction occurring after orthotopic liver transplantation.


Subject(s)
Liver Failure/surgery , Liver Transplantation/adverse effects , Nervous System Diseases/etiology , Humans , Italy/epidemiology , Morbidity/trends , Nervous System Diseases/epidemiology , Survival Rate/trends , Transplantation, Heterotopic
15.
Food Addit Contam ; 22(3): 251-8, 2005 Mar.
Article in English | MEDLINE | ID: mdl-16019793

ABSTRACT

A new, rapid and sensitive method is reported for the multiresidual determination of type A (diacetoxyscirpenol, HT-2 toxin, T-2 toxin) and type B (nivalenol, deoxynivalenol, fusarenon X, 15-O-acetyl-4-deoxynivalenol) trichothecenes in wheat flour samples. Sample extraction was performed with acetonitrile/water mixtures. Mycosep columns were used for a fast and effective clean-up procedure. The analytes were separated by HPLC with a RP C18 column by means of a gradient elution and detected in an ESI-interfaced single quadrupole mass spectrometer. Type B and type A trichothecenes were monitored in the negative and in the positive ion mode, respectively. The method performance is reported in terms of linearity (r2 = 0.999), specificity, accuracy (recoveries from 70-120%) and precision (CV% = 5), the LOQs are in the range 10-20 microg/Kg.


Subject(s)
Chromatography, High Pressure Liquid/methods , Flour/analysis , Mycotoxins/analysis , Trichothecenes/analysis , Triticum , Drug Residues/analysis , Food Contamination/analysis , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization/methods , T-2 Toxin/analogs & derivatives , T-2 Toxin/analysis
16.
J Chromatogr A ; 1047(2): 241-7, 2004 Aug 27.
Article in English | MEDLINE | ID: mdl-15460255

ABSTRACT

A method for the simultaneous LC-fluorescence detection (FLD) determination of eight trichothecenes A and B by pre-column derivatization with coumarin-3-carbonyl chloride, a highly fluorescent fluorophore, has been developed. The reaction conditions (temperature, reaction time, reactant ratios) were optimized to give a reproducible quantitative conversion. All derivatives were characterized by LC-MS. The chromatographic parameters were optimized (column, eluent) to give a very good separation of three type A (diacetoxyscirpenol, T-2 toxin, HT-2 toxin) and five type B trichothecenes [deoxynivalenol (DON), nivalenol, fusarenon-X, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol]. The best conditions were obtained on a narrow-bore C18 column with a water-methanol gradient. The detection limits (S/N = 3:1) in grain samples, with an injected volume of 5 microl, were 0.2-1 ng/g for all trichothecenes. These values are more than one order of magnitude lower than those of other LC-FLD and LC-MS methods and are similar to those obtained by GC-MS. The calibration curves were linear between 100 and 2500 ng/g. The method was successfully applied to the analysis of a certified wheat reference material, after solvent extraction and clean-up on a Mycosep column, obtaining a good recovery (89% for DON) and a high accuracy (z-score value: 0.67).


Subject(s)
Chromatography, Liquid/methods , Coumarins/chemistry , Fluorescent Dyes/chemistry , Spectrometry, Fluorescence/methods , Trichothecenes/analysis , Calibration , Food Analysis , Sensitivity and Specificity
17.
J Chromatogr A ; 937(1-2): 31-40, 2001 Dec 07.
Article in English | MEDLINE | ID: mdl-11765082

ABSTRACT

The effect of succynil-beta-cyclodextrin (beta-CD-Su), dimethyl-beta-cyclodextrin (DIMEB) and beta-cyclodextrin (beta-CD) on the fluorescence of aflatoxins B1, B2, G1, G2 and M1 (AFB1, AFB2, AFG1, AFG2 and AFM1) was studied: beta-CD-Su promoted the largest fluorescence enhancement for AFB1 and AFM1 while DIMEB showed better results for AFG1 . On the basis of the fluorescence enhancement, a new RP-HPLC method for detecting aflatoxins B1, B2, G1, G2 and M1 was developed using cyclodextrins directly dissolved in the LC eluent. Aflatoxins B1, B2, G1 and G2 were resolved using a MICRA NPS ODS-1 column using methanol-water as mobile phase to which 6 x 10(-3) M beta-CD-Su or beta-CD were added. Chromatographic responses of AFB1 and AFG1 achieved using beta-CD dissolved in the mobile phase were enhanced, respectively, 8 and 12 times, and 10 and 15 times with beta-CD-Su. Detection limits lower than 0.3 microg/kg were achieved for all the four aflatoxins. Aflatoxin M1 was analysed using a Spherisorb S3 ODS-2 Narrow Bore column and methanol-water as mobile phase with added 2 x 10(-3) M beta-CD-Su. An area enhancement of 1.5 was detected for the toxin and the detection limit achieved under these analytical conditions was lower than 0.0005 microg/kg. Both methods were statistically validated showing a linear response for all the aflatoxins tested (R2 > or = 0.99), and applied to the analysis of spiked and naturally contaminated food samples.


Subject(s)
Aflatoxins/analysis , Animal Feed/analysis , Chromatography, High Pressure Liquid/methods , Cyclodextrins/chemistry , Food Analysis , Sensitivity and Specificity , Spectrometry, Fluorescence
18.
Theor Appl Genet ; 90(5): 650-8, 1995 Apr.
Article in English | MEDLINE | ID: mdl-24174023

ABSTRACT

Two biotypes of the bread-wheat cultivar Alpe were shown to possess contrasting alleles at each of the glutenin (Glu-B1, Glu-D1, Glu-B3 and Glu-D3) and gliadin (Gli-B1 and Gli-D1) loci on chromosomes 1B and 1D. Fourteen near-isogenic lines (NILs) were produced by crossing these biotypes and used to determine the genetic control of both low-molecular-weight (LMW) glutenin subunits and gliadins by means of one-dimensional or two-dimensional electrophoresis. Genes coding for the B, C and D groups of EMW subunits were found to be inherited in clusters tightly linked with those controlling gliadins. Southern-blot analysis of total genomic DNAs hybridized to a γ-gliadin-specific cDNA clone revealed that seven NILs lack both the Gli-D1 and Glu-D3 loci on chromosome 1D. Segregation data indicated that these "null" alleles are normally inherited. Comparison of the "null" NILs with those possessing allele b at the Glu-D3 locus showed one B subunit, seven C subunits and two D subunits, as fractionated by two-dimensional A-PAGExSDS-PAGE, to be encoded by this allele. Alleles b and k at Glu-B3 were found to code for two C subunits plus eight and six B subunits respectively, whereas alleles b and k at Gli-B1 each controlled the synthesis of two ß-gliadins, one γ and two ω-gliadins. The novel Gli-B5 locus coding for two ω-gliadins was shown to recombine with the Gli-B1 locus on chromosome 1B. The two-dimensional map of glutenin subunits showed α-gliadins encoded at the Gli-A2 locus on chromosome 6A. The use of Alpe NILs in the study of the individual and combined effects of glutenin subunits on dough properties is discussed.

19.
Theor Appl Genet ; 86(2-3): 389-99, 1993 Apr.
Article in English | MEDLINE | ID: mdl-24193488

ABSTRACT

The inheritance and biochemical properties of gliadins controlled by the group 1 chromosomes of the high-quality bread wheat cultivar Neepawa were studied in the progeny of the cross Neepawa x Costantino by six different electrophoretic procedures. Chromosome 1B of Neepawa contains two gliadin loci, one (Gli-B1) coding for at least six ω- or γ-gliadins, the other (Gli-B3) controlling the synthesis of gliadin N6 only. The map distance between these loci was calculated as 22.1 cM. Amongst the chromosome 1A gliadins, three proteins are encoded at the Gli-A1 locus whereas polypeptides N14-N15-N16 are controlled by a remote locus which recombines with Gli-A1. Six other gliadins are controlled by a gene cluster at Gli-D1 on chromosome 1D. Canadian wheat cultivars sharing the Gli-B1 allele of Neepawa were found to differ in the presence or absence of gliadin N6. The electrophoretic mobilities of proteins N6 and N14-N15-N16 were unaffected by the addition of a reducing agent during two-dimensional sodium dodecyl sulphate polyacrylamid-gel electrophoresis, suggesting the absence of intra-chain disulphide bonds in their structure.

20.
J Mol Recognit ; 5(4): 139-44, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1339482

ABSTRACT

Bulk liquid membrane transport of Ca2+ and Na+ ions was performed with dicarboxylic type ligands containing (S)-phenylalanine (Phe-2-O) and (S)-benzyltyrosine (Bz-Tyr-2-O) in pH gradients. With Bz-Tyr-2-O, calcium was generally favoured at every pH, the transport rate strongly depending upon the ligand concentration. At pH 8, a reversal of selectivity (Na+/Ca2+) was observed for the first time at low ligand concentration, thus suggesting that a supramolecular-type of transport occurs as a consequence of the different assemblages formed by the ligand according to pH and concentration. This is the first case of M2+/M+ selectivity induced by the carrier concentration.


Subject(s)
Calcium/metabolism , Dicarboxylic Acids/metabolism , Sodium/metabolism , Binding, Competitive , Biological Transport , Hydrogen-Ion Concentration , Ligands , Magnetic Resonance Spectroscopy , Membranes, Artificial
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