bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal Generic Advertising with a Rationed Related Good: The Case of Canadian Beef and Chicken Markets
Authors: Cranfield J. A. L.
Published: July 2007

An optimal advertising rule is derived for a good sold in an open market (beef) when a related substitute good (chicken) is production rationed and whose imports are subject to trade restrictions. Such a rule is developed using a multi‐market equilibrium displacement model that reflects demand interrelatedness, open trade of the advertised good (beef), with rationed production and restricted trade of the related good (chicken). The optimal rule nests earlier optimal advertising rules under a variety of conditions. Results underscore the importance of accounting for cross‐product advertising effects. When these effects are present (absent), the optimal generic beef advertising intensity in Canada is shown to fall (rise) with elimination of supply management in Canada's chicken sector.

L'auteur dérive une règie sur l'optimisation de la publicité pour un produit vendu sur un marché libre (bœuf) en présence d'un produit de substitution rationné dont on restreint les importations. Pour parvenir à une telle règie, l'auteur a utilisé un modèle de déplacement du point d'équilibre sur un marché multiple illustrant les liens entre la demande des produits concernés, le libre‐échange du produit faisant l'objet de la publicité (bœuf) et la restriction de la production et des importations du produit apparenté (poulet). La règie d'optimisation englobe les règles antérieures sur l'optimisation de la publicité dans diverses situations. Les résultats soulignent qu'il est important de prendre en compte les retombées de la publicité sur les autres produits. Au Canada, en présence (absence) de telles retombées, le degré optimal de publicité générique sur le bœuf diminue (augmente) avec l'abolition de la gestion de l'offre de poulet.
Estimating the Implicit Prices of Beef Cattle Attributes: A Case from Alberta
Authors: Walburger Allan M.
Published: July 2007

Pressures on beef producers to provide lean beef of consistent quality have been mounting in recent years. Yet this requires beef breeders to alter and broaden cattle improvement objectives to include carcass merit traits. They need information on heritability and the values associated with genetic traits in order to effectively do this. This study estimates the implicit prices in east‐central Alberta, Canada, for bull attributes using a hedonic pricing model. The results indicate that the most important bull attributes to buyers (breeders) in this region are sale weight, birth weight and scrotal circumference. Also important are ribeye area and average daily gain. Selection of these attributes conforms with expectations because they are moderately to highly heritable and are associated with improved fertility and reproduction, reduced production costs and higher returns. In addition, the results suggest that breeders have been changing selection emphasis away from reproduction traits and toward carcass traits associated with improved production efficiency and consumer demand.

Depuis quelques années, les producteurs subissent des pressions grandissantes pour fournir du bœuf maigre de qualité uniforme. Ces pressions contraignent les éleveurs à modifier et àélargir leurs objectifs d'hybridation en y incluant les caractères génétiques qui codent les paramètres de la carcasse. Pour y arriver, les éleveurs ont besoin de renseignements sur l'héritabilité et la valeur des caractères en question. Dans cet article, le prix implicite des attributs des taureaux dans le centre‐est de l'Alberta est estimé selon un modèle hédoniste. Les attributs les plus importants pour les acheteurs (éleveurs) de la région sont le poids à la vente, le poids à la mise bas et la circonférence du scrotum. Comptent aussi pour beaucoup la surface du faux‐filet et le gain quotidien moyen. La sélection de tels attributs est conforme aux prévisions, car il s'agit de caractères très héréditaires qu'on relie à une fertilité accrue et de meilleures aptitudes à la reproduction, done à une réduction des coûts d'élevage et à un rendement plus élevé. Par ailleurs, les résultats de l'analyse laissent croire que les éleveurs ont réorienté leurs programmes de sélection, laissant de côté les aptitudes à la reproduction pour les paramètres de la carcasse associés à un meilleure productivité et à la demande des consommateurs.
A Case Report of Syndrome of Inappropriate Secretion of Antidiuretic Hormone With Marked Edema Due to Administration of Hypertonic Saline
Authors: Maeda Hiroto , Tsuruya Kazuhiko , Yotsueda Hideki , Taniguchi Masatomo , Tokumoto Masanori , Hirakata Hideki , Iida Mitsuo
Published: July 2007

Abstract:  A 61‐year‐old man had hyponatremia (serum Na 112 mmol/L), which was associated with disturbance of consciousness. Therefore, administration of hypertonic saline was commenced. Eventually he was diagnosed with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Hypertonic saline was continued for 45 days, and plasma Na concentration rose to 138 mmol/L. At that time we were consulted regarding further administration of hypertonic saline. At the time of the consultation marked edema had developed affecting the whole body. The cardiothoracic ratio was increased and pleural effusion was evident on the chest X‐ray. Administration of hypertonic saline was discontinued to prevent further worsening of the edema. Furthermore, water restriction (500 mL/day) was started. Body weight decreased by 4.3 kg in 7 days and the edema was diminished. However, plasma Na concentration decreased to 117 mmol/L. At that stage, we needed to balance the treatment of hyponatremia to the increased extracellular fluid volume (ECF). To normalize the ECF, we carried out ultrafiltration (UF) three times. Resolution of edema by using an extracorporeal UF method allowed the control of plasma Na concentration. In this case increased ECF volume hindered the adjustment of plasma Na concentration. The infusion of hypertonic saline is now used commonly by physicians. It is necessary to consider the potential risks of such treatment.
A Case Report of Interferon β Monotherapy for High Hepatitis C Viral Load in Dialysis Patients
Authors: Nakajima Fumitaka , Fukii Masayoshi , Kitamura Testuya , Sakaida Aya , Sakaguchi Masahiro , Oka Hiroshi , Morimoto Satoshi , Masaki Hiroya , Yamahara Hideki , Shibahara Nobuhisa , Inoue Toru
Published: July 2007

Abstract:  A 42‐year‐old male dialysis patient was infected with hepatitis C virus (HCV), and treated with interferon β (IFN‐β) for a rapid increase in viral load. After dialysis three times a week, 3 million units of IFN‐β were intravenously infused for 1 h. The treatment was markedly effective, and the virus was eliminated in the sixth week. Therapy was continued for 24 weeks, and HCV negativity has been maintained for more than 6 months after the completion of administration. The blood IFN level slowly decreased immediately after administration. The mean trough level was 37 U/mL, and the half‐life was 65 min. No adverse event requiring discontinuation of the treatment occurred, showing that IFN alone may safely eliminate the virus in dialysis patients with high hepatitis C viral load. Many dialysis patients are latently infected with HCV, and the infection affects the prognosis. Therefore, establishment of a therapeutic method is urgently needed.
Plasma Insulin is Removed by Hemodialysis: Evaluation of the Relation Between Plasma Insulin and Glucose by Using a Dialysate With or Without Glucose
Authors: Abe Masanori , Kaizu Kazo , Matsumoto Koichi
Published: July 2007

Abstract:  The aim of the present study was to evaluate the alteration in plasma immunoreactive insulin (IRI) and glucose concentrations due to hemodialysis (HD) treatment by using a dialysate with or without glucose in HD patients. We divided the patients into three groups: non‐diabetic patients (n‐DM group), well‐controlled diabetic patients (HbA1c <7.0% [w‐DM group]), and poorly‐controlled diabetic patients (HbA1c≥7.0% [p‐DM group]). Using a dialysate with a glucose concentration of 100 mg/dL (glu(+)‐dialysate) and a glucose‐free dialysate (glu(−)‐dialysate), we studied the daily profiles of plasma glucose in the three groups. We measured the levels of plasma glucose and IRI at three time points (predialysis and 2 h and 4 h after the initiation of dialysis) at pre(A) and postdialyzer (V) sites in HD patients. There was a significant increase in the daily profiles of the plasma glucose level from the time before dinner until bedtime in both the w‐DM and p‐DM groups, when comparing the values on an HD day with those on a non‐HD day. In the p‐DM group, the use of the glu(−)‐dialysate resulted in a significant hyperglycemia in the evening hours when compared with the use of the glu(+)‐dialysate. In the DM group, the use of the glu(+)‐dialysate resulted in a significant decrease in the plasma glucose and IRI levels during HD. However, in the n‐DM group, there was no difference in the plasma glucose levels during HD. On the other hand, the use of a glucose‐free dialysate led to a significant decrease in the plasma glucose and IRI levels during HD in all groups. The plasma IRI levels decreased significantly between the A and V sites at each point in all groups irrespective of the glucose concentration of the dialysate. The present study confirmed that the concentration of not only glucose but also IRI had decreased during the passage of the plasma through the dialyzer. In HD patients with diabetes, the glucose content of the hemodialysis solution plays an important role in preventing acute hypoglycemia and hyperglycemia on HD days.
Influence of concurrent exercise or nutrition countermeasures on thigh and calf muscle size and function during 60 days of bed rest in women
Authors: Trappe T. A. , Burd N. A. , Louis E. S. , Lee G. A. , Trappe S. W.
Published: July 2007

Aim:  The goal of this investigation was to test specific exercise and nutrition countermeasures to lower limb skeletal muscle volume and strength losses during 60 days of simulated weightlessness (6° head‐down‐tilt bed rest).

Methods:  Twenty‐four women underwent bed rest only (BR, n = 8), bed rest and a concurrent exercise training countermeasure (thigh and calf resistance training and aerobic treadmill training; BRE, n = 8), or bed rest and a nutrition countermeasure (a leucine‐enriched high protein diet; BRN, n = 8).

Results:  Thigh (quadriceps femoris) muscle volume was decreased (P < 0.05) in BR (−21 ± 1%) and BRN (−24 ± 2%), with BRN losing more (P < 0.05) than BR. BRE maintained (P > 0.05) thigh muscle volume. Calf (triceps surae) muscle volume was decreased (P < 0.05) to a similar extent (P > 0.05) in BR (−29 ± 1%) and BRN (−28 ± 1%), and this decrease was attenuated (P < 0.05) in BRE (−8 ± 2%). BR and BRN experienced large (P < 0.05) and similar (P > 0.05) decreases in isometric and dynamic (concentric force, eccentric force, power and work) muscle strength for supine squat (−19 to −33%) and calf press (−26 to −46%). BRE maintained (P > 0.05) or increased (P < 0.05) all measures of muscle strength.

Conclusion:  The nutrition countermeasure was not effective in offsetting lower limb muscle volume or strength loss, and actually promoted thigh muscle volume loss. The concurrent aerobic and resistance exercise protocol was effective at preventing thigh muscle volume loss, and thigh and calf muscle strength loss. While the exercise protocol offset ∼75% of the calf muscle volume loss, modification of this regimen is needed.
Ethnic and Racial Segregation: A Critical Perspective
Authors: Phillips Deborah
Published: July 2007

This review adopts a critical perspective on geographical research on ethnic and racial segregation. It seeks to address four key questions. First, how can we conceptualize ethnic and racial segregation and what are the implications for geographical research? Second, how can we best measure ethnic and racial segregation? Questions about the politics of data collection, categorization and representation are addressed. Third, what does ethnic and racial segregation mean? The article examines the different forces underlying clustering and the way in which levels of segregation have become an indicator of migrant integration. Finally, the article reflects on how statistics and visual representations of minority ethnic segregation might be used in the political and policy sphere. It concludes that a critical perspective on ethnic and racial segregation requires us to acknowledge the gaps and silences in the data produced and the complexity, and often value‐laden nature, of our interpretations.
High Amylose Cornstarch Decreases Plasma Triacylglycerol Concentration, but not Plasma Cholesterol, in a Dose‐Dependent Manner
Authors: Liu Xiong , Kishida Taro , Ebihara Kiyoshi
Published: July 2007

ABSTRACT:  The effect of dietary high amylose cornstarch (HACS) on plasma lipids was studied in ovariectomized rats (OVX‐rats). OVX‐rats were fed cholesterol‐free purified diets containing either 0%, 5%, 10%, 20%, or 30%HACS as a percentage of total carbohydrate for 28 d. Plasma triacylglycerol (TAG) concentration and apparent starch digestibility were found to decrease as the dietary level of HACS increased. On the other hand, the amount of small intestinal bile acids, cecal tissue weight, the amount of cecal short‐chain fatty acids, primary:secondary ratio of fecal bile acids, and fecal weight were found to increase. However, plasma total cholesterol concentration, excretion of fecal bile acids, cholesterol 7α‐hydroxylase activity, liver lipids, body weight gain, liver weight, and the weight of cecal contents were not affected by the diets. The amount of propionic acid in the cecal content increased as the dietary level of HACS increased. HACS might lower lipogenesis in liver and adipose tissue and lower very low density lipoprotein secretion by increasing propionic acid production, consequently leading to a decreased plasma TAG concentration.
Improving Functional Properties of Soy Protein Hydrolysate by Conjugation with Curdlan
Authors: Junfeng Fan , Yanyan Zhang , Szesze Tan , Fengjuan Li , Manyu Zhou , Saito Masayoshi , Tatsumi Eizo , Lite Li
Published: July 2007

ABSTRACT:  Soy protein hydrolysate was conjugated with curdlan through the naturally occurring Maillard reaction to extend its application in food processing. The gel‐forming and emulsifying properties of soy protein hydrolysates were significantly improved (P < 0.05) by conjugation with curdlan. The soy protein hydrolysate–curdlan conjugate (SPHCC)–soy protein isolate (SPI) mixed gel had a much thicker network than the soy protein hydrolysate and SPI mixed gel judged from scanning electron microscopic images. The improvement of gelling properties of soy protein hydrolysate by curdlan‐conjugate was attributed to both the decrease in the repulsive forces among soy protein hydrolysates and the increase in the solubility. The covalent binding of soy protein hydrolysates and curdlan also showed a profound effect on the antioxidative activity of the soy protein hydrolysates. The higher antioxidative activity of SPHCC was related to the peptide reductants produced from the Maillard reaction and the higher emulsifying property of SPHCC. The conjugates of soy protein hydrolysate and curdlan can be used as a functional food additive having excellent gel‐forming, emulsifying properties and antioxidative activity.
Spray‐Drying of Amylase Hydrolyzed Sweetpotato Puree and Physicochemical Properties of Powder
Authors: Grabowski J. A. , Truong V.‐D. , Daubert C. R.
Published: July 2007

ABSTRACT:  Spray‐drying, which has been used for commercial production of functional ingredients from several fruits and vegetables, has not yet been studied for sweetpotato processing. Thus, the objective was to determine the effects of viscosity reduction of sweetpotato puree with alpha‐amylase, maltodextrin (MD) addition, and inlet air temperature on the physicochemical characteristics of spray‐dried sweetpotato powder. A face‐centered cube design was used to evaluate the effects of amylase level (0, 3.75, and 7.5 mL/kg puree), MD concentration (0%, 10%, and 20%), and inlet air temperature (150 °C, 190 °C, and 220 °C) on powder characteristics. Model‐fitting using response surface methodology was performed to examine the effects of independent variables on the moisture content, color, water absorption, solubility, particle size, bulk density, and glass transition temperature. The data were fit to a full second order polynomial equation. However, only the linear and quadratic terms proved to be significant for most dried powder attributes. MD significantly increased powder solubility, altered the hue value, and raised the glass transition temperature of the powder. Pretreatment with alpha‐amylase resulted in a lower glass transition temperature and a decrease in particle size. Overall, results show that good quality sweetpotato powders can be produced using this drying method, with potential applications in food and nutraceutical products.
Recovery of Components from Shrimp (Xiphopenaeus kroyeri) Processing Waste by Enzymatic Hydrolysis
Authors: De Holanda Helenice Duarte , Netto Flavia Maria
Published: July 2007

ABSTRACT:  Industrial shrimp waste is a good source of protein, chitin, and carotenoids. In general, this waste is discarded with no attempt to use it, thus contributing to environmental pollution. This study was aimed at recovering the 3 main components of industrial shrimp waste, protein, chitin, and astaxanthin, using enzymatic treatment with Alcalase and pancreatin. An increase in the degree of hydrolysis (DH) from 6% to 12% resulted in 26% to 28% protein recovery. Alcalase was more efficient than pancreatin, increasing the recovery of protein from 57.5% to 64.6% and of astaxanthin from 4.7 to 5.7 mg astaxanthin/100 g of dry waste, at a DH of 12%. The enzymatic hydrolysis of the industrial waste from Xiphopenaeus kroyeri shrimp using Alcalase allowed for 65% protein recovery in the form of hydrolysates, in addition to providing suitable conditions for the recovery of astaxanthin and chitin.
Thermal Conductivity of Pear, Sweet‐cherry, Apricot, and Cherry‐plum Juices as a Function of Temperature and Concentration
Authors: Magerramov M.A. , Abdulagatov A.I. , Azizov N.D. , Abdulagatov I.M.
Published: July 2007

ABSTRACT:  The thermal conductivity of 4 fruit (pear, sweet‐cherry, apricot, and cherry‐plum) juices was measured with a coaxial‐cylinder (steady‐state) technique. Measurements were made, temperature range 20 to 120 °C, at concentrations between 12.2 and 50 °Brix. The uncertainty of the thermal conductivity measurements was estimated to be less than 2%. A semitheoretical method for the prediction of thermal conductivity of juices was proposed. It was found that the prediction Model IV, λ (T, x)/λ (T0, x) = (T/T0)n, where λ is the thermal conductivity, x is the concentration, and T is the temperature, developed in this work can be adopted with satisfaction. The thermal conductivity of juices can be predicted just by knowing the thermal conductivity λ0 at a reference temperature T0.
Physiology and Quality Responses of Fresh‐cut Broccoli Florets Pretreated with Ethanol Vapor
Authors: Han Junhua , Tao Weiyu , Hao Huakun , Zhang Bolin , Jiang Weibo , Niu Tiangui , Li Quanhong , Cai Tongyi
Published: July 2007

ABSTRACT:  The exposure of intact broccoli to 6 mL/kg ethanol for 5 h was effective in inhibiting the senescence of fresh‐cut broccoli florets. During the 8 d of storage at 10 °C, the weight loss, protein, and chlorophyll degradation of the treated broccoli florets were significantly retarded. The ethanol content of the ethanol‐treated broccoli rose sharply and then descended rapidly to a level close to that of the control broccoli stored at 10 °C after 8 d. The acetaldehyde level of the treated broccoli was higher than that of the control broccoli over the whole storage period. The alcohol dehydrogenase activity of the treated broccoli was significantly higher than that of the control after 6 d. There had been higher activities of peroxidase, superoxide dismutase, and catalase in ethanol‐treated broccoli. Our study showed that the fresh‐cut broccoli treated with ethanol maintained better quality during the storage. Ethanol vapor would be commercially a good candidate for extending the shelf‐life of fresh‐cut broccoli florets and reducing the loss in postharvest.
Determination of Critical Oxygen Level in Packages for Cooked Sliced Ham to Prevent Color Fading During Illuminated Retail Display
Authors: Larsen H. , Westad F. , Sørheim O. , Nilsen L.H.
Published: July 2007

ABSTRACT:  The effect of packages with different oxygen transmission rates (OTR), different gas‐to‐product‐volume (GP) ratios, and various levels of residual oxygen after packaging on the color stability of cooked ham exposed to commercial retail light conditions was studied. Sliced cooked ham was packaged in thermoformed packages with OTR of 0.04 and 0.06 mL O2/pkg × 24 h and GP ratios of 2.6 and 4.1. After packaging, the packages were additionally divided into groups with 4 levels of residual oxygen ranging from 0.09% to 0.46%. The packaged ham was stored in darkness at 4 °C up to 33 d, and during the storage period samples were withdrawn and exposed to light for 2 d before instrumental and visual color evaluation. In order to maintain an acceptable color of this particular ham product when exposed to typical retail light conditions, the highest acceptable level of oxygen in the headspace of the packages was 0.15% oxygen at the time of illumination. This threshold level was independent of the storage time before light exposure. A residual oxygen level of below 0.15% just after packaging combined with the package with the lowest OTR (0.04 mL O2/pkg × 24 h) and the lowest GP ratio (2.6) was the optimal condition for maintaining the color of the tested ham product throughout the entire storage period.
Interactions of Milk Proteins and Volatile Flavor Compounds: Implications in the Development of Protein Foods
Authors: Kühn Janina , Considine Thérèse , Singh Harjinder
Published: July 2007

ABSTRACT:  This review encompasses the binding of volatile flavor compounds by milk proteins in aqueous solutions. The presence of proteins in a food matrix can result in a decrease in aroma perception and in an unpleasant aroma profile, because of binding of the desirable flavor compounds to proteins. Hence, various analytical methods used to measure the extent and the type of binding, and the determination of the binding parameters, are evaluated in this review. The binding of various flavor compounds by individual milk proteins is discussed and compared in terms of their binding affinity for flavor compounds. Furthermore, the influence of temperature and ultra‐high pressures on the interactions between proteins and flavors is considered in detail. The implications of protein–flavor binding in the development of protein foods are discussed.
Monoclonal antibody fluorescence for routine lymphocyte subpopulation analysis with the Abbott CELL‐DYN Sapphire haematology analyser
Authors: MOLERO T. , LEMES A. , DE LA IGLESIA S. , SCOTT C. S.
Published: July 2007

Using previously described procedures, this study quantified T‐cell, T‐cell subset, B‐cell and NK‐cell populations with the CD‐Sapphire haematology analyser in a series of patients with mild to moderate lymphocytosis. Lymphocyte counts ranged from 6.0 to 14.9 × 109/l, with 86/97 being <10.0 × 109/l. Immunophenotyping (CD3/CD19/HLA‐DR, CD4/CD8 and CD16/CD56 combinations) was performed using EDTA‐anticoagulated blood, automated CD‐Sapphire analysis and subsequent software processing. Of 35 samples from younger (<12 years) patients, 22 (63%) had nonspecific lymphocyte changes, 4 (11%) showed specific increases in nonreactive T‐Helper or T‐Suppressor cells, and five showed a reactive T‐cell lymphocytosis. The remaining four were classified as ‘Transient/Persistent NK‐associated (NKa) Expansion’ (n = 3) and specific B‐cell lymphocytosis (n = 1). For older patients (n = 59), 15 (25%) had an increase (>1.5 × 109/l) in B‐cells, and seven investigated for surface immunoglobulin expression were all found to be clonal. The remaining samples were categorized as ‘Transient/Persistent NK‐associated (NKa) Expansion’ (13/59), Reactive Lymphocytosis (5/59), ‘Reactive Lymphocytosis or Transient/Persistent NKa Expansion’ (8/59), specific T‐Helper cell (n = 8) or T‐Suppressor cell (n = 3) lymphocytosis, and ‘Lymphocytosis of Undetermined Significance’ (n = 7). This study has demonstrated the feasibility of applying limited immunophenotyping protocols to the investigation of patients with abnormal lymphocyte counts in routine haematology. By using commercially purchased liquid monoclonal reagents to determine lymphocyte subpopulation profiles, haematology laboratories can provide more definitive information of potential clinical importance.
Bio‐maleimide as a generic stain for detection and quantitation of microparticles
Authors: ENJETI A. K. , LINCZ L. , SELDON M.
Published: July 2007

Microparticles (MP) are small fragments of cytoplasm shed from a cell surface and their role in the pathophysiology of disease is being extensively investigated. A novel staining technique for quantifying total MP in peripheral blood was evaluated in this study. Evaluation of Bodipy‐maleimide (or bio‐maleimide) as a stain for quantifying total MP in peripheral blood by flow cytometry. Samples were obtained from 10 healthy donors after informed consent. Plasma was prepared by sequential centrifugation at 1500 g followed by 13 000 g and stained with Annexin V and bio‐maleimide. Enumeration beads were added after 15 min of incubation with the stain and samples analyzed on a FACS Canto flow cytometer. Detection and quantification of MP by bio‐maleimide staining was comparable with that by Annexin V. The total mean MP level with bio‐maleimide staining was 34 ± 19.7/μl (range of 11.6–68.1/μl) and with Annexin V staining it was 38.9 ± 29.8/μl (range of 10.6 to 112.9/μl). There was no significant difference using a paired t‐test and methods were comparable using a Bland–Altman plot. Bio‐maleimide is a useful and inexpensive stain to measure total MP levels in peripheral blood by flow cytometry. This technique could be employed to study thrombotic risks in a variety of disease states.
Mechanisms of neuronal chloride accumulation in intact mouse olfactory epithelium
Authors: Nickell William T. , Kleene Nancy K. , Kleene Steven J.
Published: July 2007

When olfactory receptor neurons respond to odours, a depolarizing Cl− efflux is a substantial part of the response. This requires that the resting neuron accumulate Cl− against an electrochemical gradient. In isolated olfactory receptor neurons, the Na+–K+–2Cl− cotransporter NKCC1 is essential for Cl− accumulation. However, in intact epithelium, a robust electrical olfactory response persists in mice lacking NKCC1. This response is largely due to a neuronal Cl− efflux. It thus appears that NKCC1 is an important part of a more complex system of Cl− accumulation. To identify the remaining transport proteins, we first screened by RT‐PCR for 21 Cl− transporters in mouse nasal tissue containing olfactory mucosa. For most of the Cl− transporters, the presence of mRNA was demonstrated. We also investigated the effects of pharmacological block or genetic ablation of Cl− transporters on the olfactory field potential, the electroolfactogram (EOG). Mice lacking the common Cl−/HCO3− exchanger AE2 had normal EOGs. Block of NKCC cotransport with bumetanide reduced the EOG in epithelia from wild‐type mice but had no effect in mice lacking NKCC1. Hydrochlorothiazide, a blocker of the Na+–Cl− cotransporter, had only a small effect. DIDS, a blocker of some KCC cotransporters and Cl−/HCO3− exchangers, reduced the EOG in epithelia from both wild‐type and NKCC1 knockout mice. A combination of bumetanide and DIDS decreased the response more than either drug alone. However, no combination of drugs completely abolished the Cl− component of the response. These results support the involvement of both NKCC1 and one or more DIDS‐sensitive transporters in Cl− accumulation in olfactory receptor neurons.
GABAAand glycine receptor‐mediated transmission in rat lamina II neurones: relevance to the analgesic actions of neuroactive steroids
Authors: Mitchell Elizabeth A. , Gentet Luc J. , Dempster John , Belelli Delia
Published: July 2007

Analgesic neurosteroids such as 5α‐pregnan‐3α‐ol‐20‐one (5α3α) are potent selective endogenous modulators of the GABAAreceptor (GABAAR) while certain synthetic derivatives (i.e. minaxolone) additionally enhance the function of recombinant glycine receptors (GlyR). Inhibitory transmission within the superficial dorsal horn has been implicated in mediating the analgesic actions of neurosteroids. However, the relative contribution played by synaptic and extrasynaptic receptors is unknown. In this study, we have compared the actions of 5α3α and minaxolone upon inhibitory transmission mediated by both GABAAand strychnine‐sensitive GlyRs in lamina II neurones of juvenile (P15–21) rats. At the near physiological temperature of 35°C and at a holding potential of −60 mV we recorded three kinetically distinct populations of miniature IPSCs (mIPSCs): GlyR‐mediated, GABAAR‐mediated and mixed GABAAR‐GlyR mIPSCs, arising from the corelease of both inhibitory neurotransmitters. In addition, sequential application of strychnine and bicuculline revealed a small (5.2 ± 1.0 pA) GlyR‐ but not a GABAAR‐mediated tonic conductance. 5α3α (1–10 μm) prolonged GABAAR and mixed mIPSCs in a concentration‐dependent manner but was without effect upon GlyR mIPSCs. In contrast, minaxolone (1–10 μm) prolonged the decay of GlyR mIPSCs and, additionally, was ∼10‐fold more potent than 5α3α upon GABAAR mIPSCs. However, 5α3α and minaxolone (1 μm) evoked a similar bicuculline‐sensitive inhibitory conductance, indicating that the extrasynaptic GABAARs do not discriminate between these two steroids. Furthermore, ∼92% of the effect of 1 μm5α3α upon GABAergic inhibition could be accounted for by its action upon the extrasynaptic conductance. These findings are relevant to modulation of inhibitory circuits within spinally mediated pain pathways and suggest that extrasynaptic GABAARs may represent a relevant molecular target for the analgesic actions of neurosteroids.
Time course of muscular, neural and tendinous adaptations to 23 day unilateral lower‐limb suspension in young men
Authors: De Boer Maarten D. , Maganaris Constantinos N. , Seynnes Olivier R. , Rennie Michael J. , Narici Marco V.
Published: July 2007

Muscles and tendons are highly adaptive to changes in chronic loading, though little is known about the adaptative time course. We tested the hypothesis that, in response to unilateral lower limb suspension (ULLS), the magnitude of tendon mechanical adaptations would match or exceed those of skeletal muscle. Seventeen men (1.79 ± 0.05 m, 76.6 ± 10.3 kg, 22.3 ± 3.8 years) underwent ULLS for 23 days (n= 9) or acted as controls (n= 8). Knee extensor (KE) torque, voluntary activation (VA), cross‐sectional area (CSA) (by magnetic resonance imaging), vastus lateralis fascicle length (Lf) and pennation angle (θ), patellar tendon stiffness and Young's modulus (by ultrasonography) were measured before, during and at the end of ULLS. After 14 and 23 days (i) KE torque decreased by 14.8 ± 5.5% (P < 0.001) and 21.0 ± 7.1% (P < 0.001), respectively; (ii) VA did not change; (iii) KE CSA decreased by 5.2 ± 0.7% (P < 0.001) and 10.0 ± 2.0% (P < 0.001), respectively; Lf decreased by 5.9% (n.s.) and 7.7% (P < 0.05), respectively, and θ by 3.2% (P < 0.05) and 7.6% (P < 0.01); (iv) tendon stiffness decreased by 9.8 ± 8.2% (P < 0.05) and 29.3 ± 11.5% (P < 0.005), respectively, and Young's modulus by 9.2 ± 8.2% (P < 0.05) and 30.1 ± 11.9% (P < 0.01), respectively, with no changes in the controls. Hence, ULLS induces rapid losses of KE muscle size, architecture and function, but not in neural drive. Significant deterioration in tendon mechanical properties also occurs within 2 weeks, exacerbating in the third week of ULLS. Rehabilitation to limit muscle and tendon deterioration should probably start within 2 weeks of unloading.
Thumb and finger forces produced by motor units in the long flexor of the human thumb
Authors: Yu W. S. , Kilbreath S. L. , Fitzpatrick R. C. , Gandevia S. C.
Published: July 2007

The uncommonly good proprioceptive performance of the long flexor of the thumb, flexor pollicis longus (FPL), may add significantly to human manual dexterity. We investigated the forces produced by FPL single motor units during a weak static grip involving all digits by spike‐triggered averaging from single motor units, and by averaging from twitches produced by intramuscular stimulation. Nine adult subjects were studied. The forces produced at each digit were used to assess how forces produced in FPL are distributed to the fingers. Most FPL motor units produced very low forces on the thumb and were positively correlated with the muscle force at recruitment. Activity in FPL motor units commonly loaded the index finger (42/55 units), but less commonly the other fingers (P < 0.001). On average, these motor units produced small but significant loading forces on the index finger (∼5.3% of their force on the thumb) with the same time‐to‐peak force as the thumb (∼50 ms), but had no significant effect on other fingers. However, intramuscular stimulation within FPL did not produce significant forces in any finger. Coherence at 2–10 Hz between the thumb and index finger force was twice that for the other finger forces and the coherence to the non‐index fingers was not altered when the index finger did not participate in the grasp. These results indicate that, within the long‐term coordinated forces of all digits during grasping, FPL motor units generate forces highly focused on the thumb with minimal peripheral transfer to the fingers and that there is a small but inflexible neural coupling to the flexors of the index finger.
Short interval intracortical inhibition and facilitation during the silent period in human
Authors: Ni Zhen , Gunraj Carolyn , Chen Robert
Published: July 2007

Following a suprathreshold transcranial magnetic stimulation (TMS) to the primary motor cortex (M1) during voluntary muscle contraction, a motor evoked potential (MEP) occurs in the target muscle followed by a silent period (SP) in the electromyographic (EMG) activities. The present study investigated how short interval intracortical inhibition (SICI) and intracortical facilitation (ICF) change during the SP. The time course of MEP and motor threshold during the SP were examined in the right first dorsal interosseous muscle. Using a triple‐pulse protocol, SICI and ICF were tested at different times during the SP. The effects of different intensities of the conditioning stimulation (CS) for SICI and ICF were also investigated during the SP and at rest. During the SP, MEP was inhibited and motor threshold was increased, whereas MEP latency and background EMG level were same as those at rest. SICI decreased during the SP over a wide range of CS intensities. ICF increased at higher CS intensity. We conclude that SICI is suppressed and ICF is facilitated during the SP and the effects are separate from the interruption of voluntary drive.
Choice reaction times for human head rotations are shortened by startling acoustic stimuli, irrespective of stimulus direction
Authors: Nijhuis Lars B. Oude , Janssen Loes , Bloem Bastiaan R. , Van Dijk J. Gert , Gielen Stan C. , Borm George F. , Overeem Sebastiaan
Published: July 2007

Auditory startle reflexes can accelerate simple voluntary reaction times (StartReact effect). To investigate the role of startle reflexes on more complex motor behaviour we formulated two questions: (1) can auditory startle reflexes shorten choice reaction times?; (2) is the StartReact effect differentially modulated when startling auditory stimuli are delivered ipsilaterally or contralaterally to an imperative ‘go’ signal? We instructed 16 healthy subjects to rotate their head as rapidly as possible to the left or to right in response to a guiding visual imperative stimulus (IS), in both a simple and choice reaction protocol. Startling acoustic stimuli (113 dB) were delivered simultaneously with the IS (from either the same or opposite side) to induce the StartReact effect. We recorded kinematics of head rotations and electromyographic responses. The StartReact effect was present during choice reaction tasks (56 ms onset reduction; P < 0.001). The presentation side of the startling stimulus (left/right) did not influence the effect in choice reaction tasks. We observed a directional effect in simple reaction tasks, but this probably occurred due to a flooring effect of reaction times. Onsets of EMG responses in neck muscles were not influenced by the direction of the acoustic startling stimulus. Startling acoustic stimuli decrease reaction times not only in simple but also in choice reaction time tasks, suggesting that startle reflexes can accelerate adequate human motor responses. The absence of a clear directional sensitivity of reaction times to startling acoustic stimuli suggests that the acceleration is not highly specific, but seems to provide a global preparatory effect upon which further tailored action can be undertaken more quickly.
Spontaneous electrical and Ca2+signals in typical and atypical smooth muscle cells and interstitial cell of Cajal‐like cells of mouse renal pelvis
Authors: Lang Richard J. , Hashitani Hikaru , Tonta Mary A. , Parkington Helena C. , Suzuki Hikaru
Published: July 2007

Electrical rhythmicity in the renal pelvis provides the fundamental drive for the peristaltic contractions that propel urine from the kidney to bladder for storage until micturition. Although atypical smooth muscles (ASMCs) within the most proximal regions of the renal pelvis have long been implicated as the pacemaker cells, the presence of a sparsely distributed population of rhythmically activeKit‐positive interstitial cells of Cajal‐like cells (ICC‐LCs) have confounded our understanding of pelviureteric peristalsis. We have recorded the electrical activity and separately visualized changes in intracellular Ca2+concentration in typical smooth muscle cells (TSMCs), ASMCs and ICC‐LCs using intracellular microelectrodes and a fluorescent Ca2+indicator, fluo‐4. Nifedipine (1–10 μm)‐sensitive driven action potentials and Ca2+waves (frequency 6–15 min−1) propagated through the TSMC layer at a velocity of 1–2 mm s−1. High frequency (10–40 min−1) Ca2+transients and spontaneous transient depolarizations (STDs) were recorded in ASMCs in the absence or presence of 1 μmnifedipine. ICC‐LCs displayed low frequency (1–3 min−1) Ca2+transients which we speculated arose from cells that displayed action potentials with long plateaus (2–5 s). Neither electrical activity propagated over distances > 50 μm. In 1 μmnifedipine, ASMCs or ICC‐LCs separated by < 30 μm displayed some synchronicity in their Ca2+transient discharge suggesting that they may well be acting as ‘point sources’ of excitation to the TSMC layer. We speculate that ASMCs act as the primary pacemaker in the renal pelvis while ICC‐LCs play a supportive role, but can take over pacemaking in the absence of the proximal pacemaker drive.
Sustained CGRP1 receptor stimulation modulates development of EC coupling by cAMP/PKA signalling pathway in mouse skeletal myotubes
Authors: Avila Guillermo , Aguilar Citlalli I. , Ramos‐Mondragón Roberto
Published: July 2007

We investigated modulation of excitation–contraction (EC) coupling by calcitonin gene‐related peptide (CGRP), which is released by motorneurons during neuromuscular transmission. Mouse skeletal myotubes were cultured either under control conditions or in the presence of 100 nm CGRP (∼4–72 h). T‐ and L‐type Ca2+ currents, immobilization resistant charge movement, and intracellular Ca2+ transients were characterized in whole‐cell patch‐clamp experiments. CGRP treatment increased the amplitude of voltage‐gated Ca2+ release ((ΔF/F)max) ∼75–350% and moderately increased both maximal L‐current conductance (Gmax) and charge movement (Qmax). In contrast, CGRP treatment did not affect their corresponding voltage dependence of activation (V1/2 and k) or T‐current density. CGRP treatment enhanced voltage‐gated Ca2+ release in ∼4 h, whereas the effect on L‐channel magnitude took longer to develop (∼24 h), suggesting that short‐term potentiation of EC coupling may lead to subsequent long‐term up‐regulation of DHPR expression. CGRP treatment also drastically increased caffeine‐induced Ca2+ release in ∼4 h (∼400%). Thus, short‐term potentiation of EC coupling is due to an increase in sarcoplasmic reticulum Ca2+ content. Both application of a phosphodiesterase inhibitor (papaverine) and a membrane‐permeant cAMP analogue (Db‐cAMP) produced a similar potentiation of EC coupling. Conversely, this potentiation was prevented by pretreatment with either CGRP1 receptor antagonist (CGRP8‐37) or a PKA inhibitor (H‐89). Thus, CGRP acts through CGRP1 receptors and the cAMP/PKA signalling pathway to enhance voltage‐gated Ca2+ release. Effects of CGRP on both EC coupling and L‐channels were attenuated at later times during myotube differentiation. Therefore, we conclude that CGRP accelerates maturation of EC coupling.
Fast changes in the functional status of release sites during short‐term plasticity: involvement of a frequency‐dependent bypass of Rac at Aplysia synapses
Authors: Humeau Yann , Doussau Frédéric , Popoff Michel R. , Benfenati Fabio , Poulain Bernard
Published: July 2007

Synaptic transmission can be described as a stochastic quantal process defined by three main parameters: N, the number of functional release sites; P, the release probability; and Q, the quantum of response. Many changes in synaptic strength that are observed during expression of short term plasticity rely on modifications in P. Regulation of N has been also suggested. We have investigated at identified cholinergic inhibitory Aplysia synapses the cellular mechanism of post‐tetanic potentiation (PTP) expressed under control conditions or after N has been depressed by applying lethal toxin (LT) from Clostridium sordellii or tetanus toxin (TeNT). The analysis of the Ca2+ dependency, paired‐pulse ratio and variance to mean amplitude relationship of the postsynaptic responses elicited at distinct extracellular [Ca2+]/[Mg2+] elicited during control post‐tetanic potentiation (PTPcont) indicated that PTPcont is mainly driven by an increase in release probability, P. The PTP expressed at TeNT‐treated synapses (PTPTeNT) was found to be similar to PTPcont, but scaled to the extent of reduction in N produced by TeNT. Despite LT inducing a decrease in N as TeNT does, the PTP expressed at LT‐treated synapses (PTPLT) was characterized by exceptionally large amplitude and bi‐exponential time course, as compared to PTPcont or the PTPTeNT. Analysis of the Ca2+ dependency of PTPLT, paired‐pulse ratio and fluctuations in amplitude of the postsynaptic responses elicited during PTPLT or the variance to mean amplitude relationship of time‐locked postsynaptic responses in a series of subsequent PTPLT indicated that an N‐driven change is involved in the early phase (1 s time scale) of PTPLT, while at a later stage PTPLT is composed of both N and P increases. Our results suggest that fast switching on of the functional status of the release sites occurs also during the early events of PTPcont. The early N‐driven phase of PTPLT is likely to be a functional recovery of the release sites silenced by Rac inactivation. This effect did not appear to result from reversion of LT inhibitory action but from bypassing the step regulated by Rac. Altogether the data suggest that Rac and the intracellular pathway which allows the bypassing of Rac are key players in new forms of short‐term plasticity that rely on fast, activity‐dependent changes in the functional status of the release sites.
Mesoscopic Phase Coherence in a Quantum Spin Fluid
Authors: Xu Guangyong , Broholm C. , Soh Yeong-Ah , Aeppli G. , DiTusa J. F. , Chen Ying , Kenzelmann M. , Frost C. D. , Ito T. , Oka K. , Takagi H.
Published: July 2007

Mesoscopic quantum phase coherence is important because it improves the prospects for handling quantum degrees of freedom in technology. Here we show that the development of such coherence can be monitored using magnetic neutron scattering from a one-dimensional spin chain of an oxide of nickel (Y
2
BaNiO
5
), a quantum spin fluid in which no classical static magnetic order is present. In the cleanest samples, the quantum coherence length is 20 nanometers, which is almost an order of magnitude larger than the classical antiferromagnetic correlation length of 3 nanometers. We also demonstrate that the coherence length can be modified by static and thermally activated defects in a quantitatively predictable manner.
MicroRNA Inhibition of Translation Initiation in Vitro by Targeting the Cap-Binding Complex eIF4F
Authors: Mathonnet Géraldine , Fabian Marc R. , Svitkin Yuri V. , Parsyan Armen , Huck Laurent , Murata Takayuki , Biffo Stefano , Merrick William C. , Darzynkiewicz Edward , Pillai Ramesh S. , Filipowicz Witold , Duchaine Thomas F. , Sonenberg Nahum
Published: July 2007

MicroRNAs (miRNAs) play an important role in gene regulatory networks in animals. Yet, the mechanistic details of their function in translation inhibition or messenger RNA (mRNA) destabilization remain controversial. To directly examine the earliest events in this process, we have developed an in vitro translation system using mouse Krebs-2 ascites cell–free extract that exhibits an authentic miRNA response. We show here that translation initiation, specifically the 5′ cap recognition process, is repressed by endogenous let-7 miRNAs within the first 15 minutes of mRNA exposure to the extract when no destabilization of the transcript is observed. Our results indicate that inhibition of translation initiation is the earliest molecular event effected by miRNAs. Other mechanisms, such as mRNA degradation, may subsequently consolidate mRNA silencing.
Correlation between laminin-5 immunohistochemistry and human papillomavirus status in squamous cervical carcinoma
Authors: Boulet G A V , Schrauwen I , Sahebali S , Horvath C , Depuydt C E , Vereecken A , Broeck D Vanden , Van Marck E A , Bogers J J
Published: July 2007

Background:Human papillomavirus (HPV) plays a critical role in the carcinogenesis of squamous cervical carcinoma. Integration of viral DNA into the host genome is a major contributing factor to malignant transformation. Viral load may influence integration.

Aims:To compare HPV status (type, viral load, integration status) between normal samples, carcinoma in situ and invasive carcinoma in order to elucidate the role of HPV in progression to invasive lesions.

Methods:The study population comprised 10 biopsy samples from each diagnostic group. Laminin-5 immunohistochemistry was performed to distinguish invasive carcinoma from non-invasive high-grade lesions. Real-time PCR was used to detect specific HPV types, viral load and integrated HPV, with quantification of viral E2 and E6 genes.

Results:Invasive carcinomas contained a higher number of laminin-5 immunoreactive cells as compared to non-invasive lesions. Almost all samples contained HPV, with a higher viral load and copy number of HPV16 integrated in E2 in cases of laminin-5 immunoreactivity and cases of invasive carcinoma. High HPV16 viral load was associated with more integrated copies in E2.

Conclusions:HPV is important in progression from carcinoma in situ to invasive carcinoma. Viral load and HPV integration influence the development of cervical cancer towards invasiveness. Overall HPV status may be more predictive of patient outcome and may influence patient management.