bluuebunny/crossref_metadata_2025_split huggingface dataset:
Postharvest Quality and Microbial Population of Head Lettuce as Affected by Moisture at Harvest
Authors: Fonseca Jorge M. 
Published: August 2010

ABSTRACTIceberg lettuce was evaluated for yield, microbial population, and postharvest quality either following different irrigation termination (IT) schedules or before and after a rainfall event. Lettuce receiving late (4 d before harvest) IT showed increased weight and diameter, higher aerobic bacteria counts, and lower quality than plants subjected to early (16 d before harvest) IT. Middle (8 d before harvest) IT produced similar yields, and lower microbial population in lettuce than late IT. After rain, microbial population increased by 1.5 and 3.0 log colony‐forming units (CFU)/g in outer and head leaves respectively. The results revealed the importance of managing moisture conditions at harvest to enhance overall quality of lettuce.
Differentiation of Crude Lipopolysaccharides from Escherichia coli Strains Using Fourier Transform Infrared Spectroscopy and Chemometrics
Authors: Kim Sol , Burgula Y. , Ojanen‐Reuhs Tuula , Cousin Maribeth A. , Reuhs Bradley L. , Mauer Lisa J. 
Published: August 2010

ABSTRACTCrude phenol‐phase extracts containing bacterial lipopolysaccharides (LPS) from 5 strains of Escherichia coli were investigated to differentiate the strains using Fourier transform infrared (FTIR) spectroscopy and multivariate statistical analysis. The strains used were E. coli K12, E. coli DH5α, E. coli O157:H7, E. coli O157:H12, and E. coli O157:H19. LPS‐containing extracts were isolated from each E. coli strain using a hot phenol‐water extraction procedure. The extracts were 1st analyzed by deoxycholic acid‐polyacrylamide gel electrophoresis and visualized by silver‐staining. Analysis of the extracts from E. coli K12 and E. coli DH5α showed rough‐type LPS on the lower half of the gel, whereas E. coli O157:H7, E. coli O157:H12, and E. coli O157:H19 yielded abundant smooth LPS (high‐molecular‐weight LPS that include the O‐polysaccharides). Spectra (4000 cm‐1 to 700 cm‐1) of crude E. coli LPS extracts and intact cells were collected using a FTIR spectrometer. Spectral data were compressed by principle component analysis and analyzed using canonical variate analysis (CVA) of 4000 cm‐1 to 700 cm‐1 or 1200 cm‐1 to 900 cm‐1 spectral regions. CVA showed better separation between strains using LPS extracts than intact cells in the 1200 cm‐1 to 900 cm‐1 spectral region. The same separation trend was found using Mahalanobis distances that quantified spectral differences between the E. coli strains, providing 80% and >95% correct classifications of intact cells and LPS extracts, respectively. This article is the first to report the successful differentiation of E. coli strains at a serotype level using FTIR spectra of bacterial phenol‐phase extracts (crude LPS preparations).
Evaluation of a Double Layer Agar Plate For Direct Enumeration of Vibrio parahaemolyticus
Authors: Duan Jingyun , Liu Chengchu , Su Yi‐Cheng 
Published: August 2010

ABSTRACTA double layer agar plate (DLAP) was developed according to the thin agar layer (TAL) method as a 1‐step procedure for direct enumeration of injured Vibrio parahaemolyticus cells based on the formation of unique purple colonies by V. parahaemolyticus. The DLAP was prepared by overlaying an equal volume (10 mL) of a nonselective medium (tryptic soy agar supplemented with 1.5% NaCl) onto a selective medium (Bio‐Chrome Vibrio medium). The DLAP was capable of detecting V. parahaemolyticus in mixed cultures containing non‐Vibrio bacteria. Production of purple colonies by V. parahaemolyticus on DLAP was not affected by the growth of other bacteria, even when V. parahaemolyticus was only a small fraction (5%) of the entire bacterial population. Direct plating on DLAP was found as effective as the most probable number (MPN) method for recovering heat‐and cold‐injured V. parahaemolyticus cells, which could not be detected by direct plating on Bio‐Chrome Vibrio medium or thiosulfate‐citrate‐bile salts‐sucrose agar. The DLAP offers an alternative to the MPN method for detecting injured V. parahaemolyticus cells and can be used as a simple 1‐step procedure for quick screening of V. parahaemolyticus in foods.
Characterization of the Fermented Milk “Laban” with Sensory Analysis and Instrumental Measurements
Authors: Chammas I. Gisele , Saliba Rachad , Béal Catherine 
Published: August 2010

ABSTRACTSensory, chemical, and rheological properties of commercial and traditional laban samples were investigated to characterize this fermented milk. One commercial sample and 14 traditional samples, collected from various geographical locations in Lebanon, were evaluated by a descriptive panel in terms of appearance, color, texture, odor, taste, and after‐taste. Principal component analysis of the sensory data revealed high differences between laban samples. They were separated into 5 distinct groups that were identified by the following sensory characteristics: firm and sour, slimy and sweet, high butter odor, high yogurt odor, and moderate levels for all the descriptors. Six samples, showing different features, were selected from these 15 samples. Physicochemical analyses of acidity, lactose and fat contents, firmness, and apparent viscosity were assessed on these 6 samples. Laban, independently of its origin, displayed higher acidity than yogurt. Commercial laban showed higher acidity and viscosity than traditional samples. Statistical relationships between sensory and instrumental data showed significant correlation between apparent viscosity and smoothness, fat content and butter odor, titratable acidity and sourness, and penetrometry readings and sliminess. Finally, principal component analysis of the instrumental and sensory parameters revealed that both analyses characterized the samples in the same way.
Influence of Texture on Taste: Insights Gained During Studies of Hardness, Juiciness, and Sweetness of Apple Fruit
Authors: Harker F. Roger , Amos Rachel L. , Echeverríaa Gemma , Gunson F. Anne 
Published: August 2010

ABSTRACTApple flesh can be considered as a living structure within which juice and tastants are encapsulated in individual cells. The breakdown of this structure and release of juice varies between hard and soft apples. We hypothesized that the texture of the fruit and the way it releases juice during chewing would therefore influence the perception of sweetness. Time‐intensity (TI) techniques were used by a trained panel to study the temporal changes in the intensity of “juiciness” and “sweetness” during consumption of apples that varied in mechanical hardness (measured by puncture test). All apple samples had a similar water content, but the pattern of juice release was markedly different. Juice was released into the mouth in a pattern of increasing and then deceasing intensity. The maximum intensity (Imax), duration of the stimulus (DUR), and area under the TI curve (AUC) were significantly higher for hard compared with soft apples. The impact of juice release on perception of sweetness was examined using apples in which the Imax and AUC for juiciness of soft apples were half the value of those for firm apples. There was no consistent difference in Imax, DUR, or AUC for sweet taste in these 2 sets of apples. We concluded that sufficient juice was released from soft and less juicy apples to ensure that sweetness perception was maximized. These results are discussed in relation to earlier studies that demonstrated that texture (thickening agents) suppresses flavor perception in solutions and juices.
Quality Characterization of Farmed Atlantic Halibut During Ice Storage
Authors: Guillerm‐Regost Christelle , Haugen Trine , Nortvedt Ragnar , Carlehöug Mats , Lunestad Bjørn Tore , Kiessling Anders , Rørár Anna Maria B. 
Published: August 2010

ABSTRACT:A quality index method (QIM) was developed for farmed Atlantic halibut and together with instrumental, chemical, sensory, and bacteriological analysis, quality changes of halibut stored on ice for 26 d was evaluated. Two groups of fish were fed diets that differed only in the source of lipid, where 1 diet contained only marine oil sources and the other a 50/50 mixture of marine and soybean oil. Fish were slaughtered after 1 y and then stored on ice for 26 d. The fish were sampled on day 1, day 2, and every 2nd day after that. Dietary lipid sources had no effect on freshness, (ATP) degradation (K‐value), texture, color, or liquid‐holding capacity. The QIM scores increased with storage time, in particular the appearance and eyes parameters. The QIM is a good freshness indicator for halibut. The K‐value was strongly correlated with storage time (r= 0.99), while total bacterial counts increased after 7 to 8 d of ice storage. The texture, liquid‐holding capacity, and color were significantly affected by storage time during the early period of storage, probably due to rigor stiffness and rigor resolution. The texture, liquid‐holding capacity, and color did not change significantly from approximately day 8 of storage until the end of the experiment at day 26.
Distribution and Regulation by Oestrogen of Fully Processed and Variant Transcripts of Gonadotropin Releasing Hormone I and Gonadotropin Releasing Hormone Receptor mRNAs in the Male Chicken
Authors: Sun Y.‐M. , Dunn I. C. , Baines E. , Talbot R. T. , Illing N. , Millar R. P. , Sharp P. J. 
Published: August 2010

AbstractThe aim of this study was to increase understanding of the occurrence and regulation of chicken gonadotropin releasing hormone I (cGnRH I) and chicken gonadotropin releasing hormone receptor (cGnRH‐R) mRNA variants in the hypothalamic‐pituitary‐testicular axis (HPTA). The study was carried out in the cockerel. Fully processed cGnRH I mRNA (cGnRH Ia) and a variant transcript (cGnRH Ib) with a retained intron 1 were observed in the preoptic/anterior hypothalamus (POA), the basal hypothalamus, anterior pituitary gland, and testes. Fully processed cGnRH‐R mRNA (cGnRH‐Ra) and a variant transcript (cGnRH‐Rb) with a deletion were detected in the same tissues. In juvenile cockerels, concentrations of cGnRH Ia and b in the POA increased after castration, and this was prevented by oestrogen treatment. In the anterior pituitary gland, the concentration of cGnRH‐Ra increased after castration and this was reversed by oestrogen treatment. In intact adult cockerels, oestrogen treatment depressed plasma luteinizing hormone but did not affect concentrations of cGnRH I and cGnRH‐R mRNAs in the POA, basal hypothalamus, and anterior pituitary gland, suggesting that locally produced oestrogen, by aromatization, may exert maximal suppression on cGnRH I and GnRH‐R mRNAs. In intact adult cockerels, the concentrations of cGnRH Ia and b in the testis, but not cGnRH‐Ra and b, were depressed by oestrogen treatment. It was concluded that fully processed and variant cGnRH I and cGnRH‐R mRNAs occur in all components of the HPTA. Oestrogen appears to play a role in the regulation of cGnRH Ia and b in the POA and testes, and of cGnRH‐Ra in the POA and anterior pituitary gland.
Gene Expression of the Insulin‐Like Growth Factor System During Postnatal Development of the Rat Pituitary Gland
Authors: González‐Parra S. , Argente J. , Chowen J. A. , Van Kleffens M. , Van Neck J. W. , Lindenbeigh‐Kortleve D. J. , Drop S. L. S. 
Published: August 2010

AbstractInsulin‐like growth factors I and II (IGFI and II) are synthesized by anterior pituitary cells and participate in cellular growth and differentiation, as well as the control of pituitary hormone secretion. Type 1 and 2 IGF receptors (IGFR1 and IGFR2) and the six IGF binding proteins (IGFBPs), which modulate IGF effects, are expressed in the anterior pituitary gland. We usedin situhybridization to analyse the temporal expression pattern of IGFI and II, IGFR1 and 2 and IGFBP1–6 in the anterior pituitary gland during postnatal development in both male and female rats (10, 20, 30, 40 and 60 days of age). We found all of the components of the IGF system to be expressed in the anterior pituitary gland, with each having a specific temporal pattern of expression. In addition, there exist differences between the sexes in the expression of some components of the IGF system. These data emphasize that in the anterior pituitary gland the IGF system is under tight regulation during postnatal life when this gland continues to develop. The distinct temporal expression of each member of the IGF system may indicate specific roles in the development and physiology of the anterior pituitary gland.
Characterization of an Antibody to the Human Melatonin mt1 Receptor
Authors: Williams L. M. , Drew J. E. , Bunnett N. W. , Grady E. , Barrett P. , Abramovich D. R. , Morris A. , Slater D. 
Published: August 2010

AbstractMelatonin acts via high affinity, G‐protein coupled, seven transmembrane domain receptors. To precisely localize these receptors, antibodies were raised in chickens against a 15 amino acid fragment at the intracellular C‐terminal region of the human melatonin receptor subtype mt1 (DSSNDVADRVKWKPS, mt1338−352). A chimeric form of the receptor with a hydrophilic Flag peptide (DYKDDDDK) in sequence with the extracellular N‐terminus (Flag‐mt1) was generated by polymerase chain reaction and expressed in mammalian cell lines. An IgY antibody (Y31), which gave high antibody titres by enzyme‐linked immunosorbent assay, was used to localize Flag‐mt1 in stably transfected cells by immunofluoresence. Flag‐mt1 localization with Y31 was identical to that obtained with the M5 antibody directed against the Flag epitope and was mainly localized to the Golgi apparatus with some staining at the cell surface. No staining was seen in untransfected cells with either antibody. Y31 staining was abolished using antibody preabsorbed with peptide antigen. Y31 immunofluorescence in fetal human kidney sections was restricted to nephrogenic regions and matched that of 2‐(125I)iodomelatonin binding and mt1 gene expression by in situ hybridization. Y31 was used to immunoprecipitate biotinylated membrane proteins from Flag‐mt1 stably transfected and untransfected CHO cells. Western blotting of immunoprecipitated proteins revealed two major bands specific to stably transfected cells, one at 63 kDa and one at 86 kDa. The first band almost certainly corresponds to the glycosylated form of Flag‐mt1 and the second band to receptor dimers. Thus, Y31 antibody is suitable for use in detecting the human mt1 receptor subtype in tissues and in transfected cells.
Photoperiodic Regulation of Prolactin Gene Expression in the Syrian Hamster by a Pars Tuberalis‐Derived Factor
Authors: Stirland J. A. , Johnston J. D. , Cagampang F. R. A. , Morgan P. J. , Castro M. G. , White M. R. H. , Davis J. R. E. , Loudon A. S. I. 
Published: August 2010

AbstractSyrian hamsters exhibit a marked seasonal variation in prolactin secretion. The aim of this study was to analyse the nature of the photoperiodic regulation of prolactin gene expression, and to define the role of melatonin and the pars tuberalis of the anterior pituitary in this process. Pituitary prolactin gene expression, restricted to the pars distalis, was increased in hamsters maintained in long daylengths (16 h : 8 h, light : dark) compared to hamsters exposed to short daylengths (8 h : 16 h, light : dark) for 8–12 weeks. Analysis of single cells by in situ hybridization showed that photoperiod had no effect on the percentage of pars distalis cells expressing prolactin mRNA, but shifted the frequency distribution of prolactin mRNA expression per cell, such that in long photoperiods a greater proportion of cells were recruited to a higher expressing population. In vitro coculture of hamster pars tuberalis fragments increased prolactin promoter‐driven luciferase activity in stably transfected GH3 cells in a dose‐ and duration‐dependent manner. Conditioned medium from hamster and ovine pars tuberalis also activated the prolactin promoter. Furthermore, basal and forskolin‐stimulated conditioned medium from hamster pars tuberalis increased prolactin mRNA expression in primary cultures of pars distalis cells. Melatonin attenuated the activity of pars tuberalis‐conditioned medium but had no direct effect on either prolactin mRNA expression or secretion in pars distalis cell cultures. Finally, pars tuberalis fragments from long photoperiod hamsters stimulated prolactin gene promoter activity to a greater extent than those from short photoperiod hamsters. In conclusion, this study provides the first evidence in a seasonal mammal that the synthesis of prolactin depends on photoperiodic modulation of a pars tuberalis‐derived factor. Our data support further the hypothesis that seasonal modulation of prolactin gene expression depends upon a melatonin‐dependent paracrine action of the pars tuberalis on pars distalis lactotrophic cells.
Actions of Leptin on Growth Hormone Secretagogue‐Responsive Neurones in the Rat Hypothalamic Arcuate Nucleus RecordedIn Vitro
Authors: Tung Y. C. L. , Hewson A. K. , Dickson S. L. 
Published: August 2010

AbstractIn the arcuate nucleus, the growth hormone (GH) secretagogue (GHS)‐responsive cells include a subpopulation of the neuropeptide Y (NPY) neurones. It is not known whether these include the orexigenic NPY population that are inhibited by the satiety hormone, leptin. Thus we investigated whether (i) the arcuate nucleus cells electrically excited by GHS are inhibited by leptin and (ii) chronic central leptin infusion alters GHS‐induced Fos expression. Of 36 cells recorded from a trimmed hypothalamic slice containing arcuate nucleus, 13 cells were excited by the nonpeptide GHS, CP‐459,599. The predominant response of these cells to leptin was inhibitory: six inhibited, three excited and four unresponsive. Similar responses were observed in a population of arcuate cells recorded from a preparation in which synaptic transmission was blocked, suggesting that leptin acts directly on a subpopulation of GHS‐responsive neurones. Intracerebroventricular infusion of leptin for 1 week did not alter the number of cells expressing Fos following GHS administration. Thus, while leptin does not appear to influence the central actions of GHS to induce immediate early gene expression, it does act directly on a subpopulation of cells excited by GHS, eliciting mostly inhibitory but also some excitatory responses. It will be interesting to discover the consequences of leptin's inhibitory effects on the hypothalamic circuits excited by GHS, particularly since leptin paradoxically has a stimulatory effect on GH secretion, presumed to reflect a suppression of central NPY pathways.
AMINO ACID COMPOSITION AND SEQUENCE ANALYSIS OF SAUVAGINE, A NEW ACTIVE PEPTIDE FROM THE SKIN OF PHYLLOMEDUSA SAWAGEI
Authors: MONTECUCCHI PIER CARLO , HENSCHEN AGNES 
Published: August 2010

The complete amino acid sequence of sauvagine, a new active polypeptide from the skin of Phyllomedusa sauvagei, a frog of Central and South America, has been determined by automated liquid‐phase procedure after specific removal of the N‐terminal pyrrolidonecarboxylic acid, and specific cleavages at the single methionine and at the two arginine residues. The proposed sequence is: Pyr‐Gly‐Pro‐Pro‐Ile‐Ser‐Ile‐Asp‐Leu‐Ser‐Leu‐Glu‐Leu‐Leu‐Arg‐Lys‐Met‐Ile‐GIu‐Ile‐Glu‐Lys‐Gln‐Glu‐Lys‐Glu‐Lys‐Gln‐Gln‐Ala‐Ala‐Asn‐Asn‐Arg‐Leu‐Leu‐Leu‐Asp‐Thr‐Ile‐NH2.Sauvagine possesses a number of pharmacological actions on diuresis, the cardiovascular system and endocrine glands; it can be considered the prototype of a new family of amphibian peptides, in addition to the tachykinins, bradykinins, dermorphins, caerulein‐like and bombesin‐like peptides.
Lysolecithin:lysolecithin acyltransferase from rabbit lung.
Authors: Arche .R. , Acebal C. , Casals C. , Estrada P. , Herrera L. 
Published: August 2010

The enzyme lysolecithin:lysolecithin acyltransferase from rabbit lung has been found to have a relatively disordered conformation in solutions of high ionic strength. The protein exhibited an ordering of structure when salt was suppressed. This conformational change was concomitant with the loss of transacylase activity, the hydrolytic reaction remaining unchanged. Addition of NaCl caused a progressive disordering of structure with a parallel increase of transacylase activity.The acid denaturation of the protein, at low and high ionic strengths, showed that the ionization of groups with pK in the range 5.9–6.4 was essential for denaturation. The structure was stable at basic pH.The addition of lipids resulted in a non‐specific stabilization of the disordered conformation, in the same manner as the addition of NaCl.From these results, it is suggested that there are two conformations for this protein which differ in their ability to bind lysolecithin molecules in the enzyme deacylation step of the reaction. This hypothesis agrees with previously published properties of the enzyme, concerning aggregation with other proteins and kinetic data. From the amino acid composition and conformational properties, the authors suggest that this enzyme could be a peripheral membrane protein.
Zur Frage einer Vitamin B12‐Zulage in der Getreideschnellmast
Authors: Wöhlbier W. , Kirchgessner M. , Giessler H. 
Published: August 2010

ZusammenfassungIn einem Schweinemastversuch mit 4 Gruppen wurde die Wirkung einer Vitamin‐B12‐Zulage zu Fertigfuttermitteln untersucht, deren Zusammensetzung sich lediglich darin unterschied, daß die Fertigfuttermittel der Gruppen I und II norwegisches Frischheringsmehl, die der Gruppen III und IV peruanisches Fischmehl enthielten. Den Gruppen II und IV wurde als Vitaman‐B12‐Zulage in den Fertigfuttermitteln für die Anfangsmast 25 μg, in den für die Mittelmast 15 μg und in den für die Endmast 10 μg Vitamin B12 je kg gegeben.Durch die mathematisch‐statistische Auswertung der einzelnen Versuchsergebnisse konnte nachgewiesen werden, daß mit einer Wahrscheinlichkeit von P < 0,2 in der Gruppe, die peruanisches Fischmehl mit Vit.‐B12‐Zulage erhalten hatte, ein geringerer Verbrauch an Trockensubstanz, verdaulichem Reineiweiß und StE je kg Gewichtszunahme sowie eine niedrigere Verwertungszahl und geringere Futterkosten erzielt worden waren als in der Gruppe, die zu dem peruanischen Fischmehl keine Vitamin‐B12‐Zulage erhalten hatte. In den Gruppen, deren Fertigfuttermittel norwegisches Frischheringsmehl enthalten hatten, konnten diese Werte durch die Zulage von Vitamin B12 nicht verbessert werden.
Beiträge zur Aminosäurebestimmung in biologischem Material
Authors: Krampitz G. , Müller R. 
Published: August 2010

ZusammenfassungErgänzend zu den vorhergehenden Mitteilungen wird über eigene Erfahrungen mit der Gradientelution nach Moore und Stein berichtet. Neben den vorbereitenden Arbeiten sind der Analysengang und die Berechnungsverfahren an Hand von Beispielen besprochen. Die Methode bietet den Vorteil hohen Auflösungsvermögens auch bei multiplen Gemischen, die unter anderem in den Körperflüssigkeiten vorkommen. Die Automatisierung ist möglich.
Wechselbeziehungen zwischen Spurenelementen in Futtermitteln und tierischen Substanzen sowie Abhängigkeitsverhältnisse zwischen einzelnen Elementen bei der Retention
Authors: Kirchgessner Manfred 
Published: August 2010

ZusammenfassungVerschiedene Futtermittel und tierische Substanzen sollen darauf untersucht werden, ob zwischen ihrem Gehalt an zwei oder mehreren Spurenelementen Wechselbeziehungen vorkommen, in welcher Größenordnung sich diese Abhängigkeitsverhältnisse bewegen, was die Ursachen dafür sein dürften und welche Bedeutung den jeweiligen Abhängigkeiten zukommt. Für die Berechnung solcher Wechselwirkungen zwischen verschiedenen Elementen wurde das Verfahren der Teilkorrelation und multiplen Regression und die entsprechenden Prüfungsverfahren vorgeschlagen. Die Notwendigkeit eines solchen Vorgehens wurde an einem Beispiel demonstriert. Außerdem wurde eine Reihe von Besonderheiten, die bei solchen Untersuchungen zu beachten sind, aufgezeigt und die entsprechenden Formeln für mehr als vier Veränderliche erweitert.