bluuebunny/crossref_metadata_2025_split huggingface dataset:
MICROTOPOGRAPHY AND BACTERIAL ADHERENCE TO FOOD CONTACT SURFACES EVALUATED BY SCANNING ELECTRON MICROSCOPY AND EPIFLUORESCENCE MICROSCOPY
Authors: CARELI ROBERTA TORRES , DE ANDRADE NÉLIO JOSÉ , DE FÁTIMA FERREIRA SOARES NILDA , RIBEIRO JÚNIOR JOSÉ IVO , ROSADO MARCÍLIA SANTOS , PINHEIRO LUIZ LÍVIA MARIA , BERNARDES PATRÍCIA CAMPOS 
Published: December 2008

ABSTRACT Microtopography of food contact surfaces used in the food industry, such as stainless steel AISI 304 #4, double‐faced smooth polyurethane (PU), and PU coated with cloth, double‐faced rugous PU, polyvinyl chloride coated with thin cloth, polyvinyl chloride coated with thick cloth, silicon coated with cloth, granite and marble, was evaluated by scanning electron microscopy. Also, the adhesion of Pseudomonas fluorescens to surfaces was evaluated by epifluorescence microscopy. Several types of imperfections were observed in the different surfaces: protuberances and cracks with diameters of 5.1 and 8.8 µm; elevations of about 3.2 µm and micro‐holes with a diameter of 6.45 µm; undulations and depressions with diameters of 26.5 and 6.9 µm, respectively, and porous surfaces about 6.12 and 13.44 µm long. The numbers of adhered cells reached 5.5–6.5 log DMC/cm2. Surfaces coated with thick cloth and marble and granite surfaces showed the highest number (P < 0.05) of adhered cells. Choosing smooth surfaces helped to control bacterial adherence.PRACTICAL APPLICATIONSThis research shows important information for people dealing with food quality control, quality management, risk assessment, risk management hazard analysis by critical point control and good manufacturing practices, which are well‐recognized food safety tools. The number of manufactured foods has widely increased to meet the increasing number of consumers and sometimes the hygiene procedures in the food industry are poor or overlooked. It is essential that those responsible for producing food be knowledgeable about the characteristics of the material surfaces used to make the equipment, utensils and conveyors to help in the control of foodborne diseases. The viable alternatives to avoid or minimize food contamination are (1) improving surface quality related to microtopography by improving surface production process; (2) choosing surfaces with better characteristics concerning microtopography to control the adherence process and biofilm formation; and (3) implementing effective controls of cleaning and sanitizing procedures.
The Effects of Large Osmolality Variations on the Gastric Mucosal Ion Permeability
Authors: Frenning Bertil 
Published: December 2008

AbstractNaCl solutions were instilled into ligated unstimulated whole stomach pouches in cats for 30 min. On instillation of distilled water or 310 or 620 mM NaCl the net fluxes of NaCl were roughly proportional to the mean concentration difference between the gastric lumen and the blood. On instillation of more than 620 mM NaCl the absorption was larger than expected from this proportionality, a result believed to be due to an increase in the permeability of the gastric mucosa on instillation of such hyperosmotic solutions. Instillation of distilled water or 310 or 620 mM NaCl had only minor effects on the net flux of hydrogen ions out of the stomach during subsequent instillations of 170 mM HCl, In comparison with the controls. On instillation of HCI subsequent to an instillation of 620 mM NaCl the net fluxes of sodium ions and water into the stomach were significantly increased over the control level and there was a net influx of chloride ions instead of a net efflux. This result was probably due to secretion of a NaCl containing fluid. On instillation of 170 mRI HCl subsequent to an instillation of 930 or 1550 mM NaCl the net effluxes of hydrogen ions also were significantly increased over the control levels. The concentration of NaCl in the instilled solution needed to obtain an effect on the gastric mucosal ion permeability, both during the instillation of NaCl and on subsequent instillation of 170 mM HCl, was thus larger than 620 mM.
Metabolism of 14C‐histamine in Amphibians (Bufo bufo) and Reptiles (Pseudemys scripta and Testudo hermanni)
Authors: Eliassen K. A. , Reite O. B. 
Published: December 2008

AbstractThe metabolism of parenterally administered 14C‐histamine was studied in the toad (B. bufo), the terrapin (P. scripta) and the tortoise (T. hermanni). Paper chromatography and isotope dilution techniques were used for estimation of 14C‐rnetabolites in urine. Urinary excretion of radioactivity usually exceeded 50 % of the total dose within 24–48 h of administration of 14C‐histamine. Methylation of histamine to 1.4‐methylhistamine and further oxidation to 1.4‐methylimidazoleacetic acid was quantitatively the most important pathway for histamine degradation, accounting for about 80 and 50 % of the radioactivity in urine of the toad and the reptiles, respectively. Oxidative deamination of histamine to imidazoleacetic acid also took place in all the studied species. In toad urine imidazoleecetic acid was found in the free form only, whereas in urine from both reptilian species most of it was bound to ribose.
The Distensibility of the Resistance Vessels in Spontaneously Hypertensive Rats (SHR) as Compared with Normotensive Control Rats (NCR)
Authors: Hallbäck Margareta , Lundgren Yen , Weiss Lilian 
Published: December 2008

AbstractEarlier studies on human essential hypertension, as well as on SHR, suggest that an increased media thickness, partly encroaching upon the vascular lumen, forms the main background of the increased flow resistance in primary hypertension (e.g. Folkow et al. 1970). In the present investigation a comparison was made concerning the distensibility of the resistance vessels in order to further explore the proposed difference in vascular design. The simultaneously perfused hindquarter vessels of SHR and NCR were exposed to sudden, repeated shifts of pressure and flow, first at maximal vasodilatation and then at stable levels of smooth muscle tone, induced by barium ions or noradrenaline. Relative changes of vascular internal radius (ri) were calculated from the pressure‐flow values, assuming ri to be proportional to 4 flow conductance. For given changes in distending pressure (Pd), the SHR resistance vessels exhibited considerably smaller percentual ri changes than the NCR ones, whether starting from the same Pd, the same ri, or even when both Pd and ri were initially kept identical in NCR and SHR by exposing the SHR vessels to lower concentrations of constrictor agents. This evidence of reduced vascular distensibility in SHR was obvious both at maximal dilation and, particularly, when smooth muscle tone was increased. This strongly supports the view that especially the media component of the SHR resistance vessels is enhanced in bulk, thus markedly influencing both “active” and “passive” resistance changes.
Studies on the Accumulation of Noradrenaline and 5‐Hydroxytryptamine by Cholesterol‐Phospholipid Microvesicles
Authors: Ahtee Liisa , Johnson S. M. 
Published: December 2008

AbstractA study was made of the accumulation of the monoamines, 5‐hydroxytryptarnine and noradrenaline, by phospholipid vesicles of similar chemical composition to the natural monoaminr storage vesicles. Although the artificial vesicles would accumulate the monoamines against a concentration gradient they were far inferior in this respect to the natural vesicles. The accumulation of the monoamines was studied as a function of time, temperature and the chemical composition of the vesicles, and the effect of osmotic shock, reserpine, metaraminol and calcium on the release of the monoamines was noted. The results indicated that the binding of 5‐hydroxytryptamine was increased by acidic phospholipids but that noradrenaline was unaffected. A temperature rise only marginally inreased the monoamine accumulation. Reserpine slightly retarded the release of noradrenalinc.
Effects of 6‐OH‐Dopamine on the Autonomic Nerves of the Rabbit Myometrium
Authors: Hervonen Antti , Kanerva Lasse 
Published: December 2008

AbstractThe degeneration of the terminal network of sympathetic nerve fibres in the rabbit uterus and oviduct were studied after treatment with 6‐OH‐Dopamine. The majority of the fluorescent fibres of the myometrial smooth muscle disappeared 24 h after the treatment. The recovery of the fluorescence required 4–7 weeks. At the finestructural level, no adrenergic axon terminals could be identified while the nonadrenergic axons and axon terminals seemed intact. Complete adrenergic denervation caln be achieved by the use of 6‐OH‐dopamine also in those regions, which are innervated through the “short adrtnergic neurones”.
Effects of Lanthanum on the Coupling between Membrane Excitation and Contraction of Isolated Frog Muscle Fibres
Authors: Andersson K.‐E. , Edman K. A. P. 
Published: December 2008

AbstractThe effects of lanthanum on the electrical and mechanical activities of isolated muscle fibres from the frog were investigated. Lanthanum, in the range 0.05–0.3 mM, produced characteristic, concentration dependent changes of the isometric twitch. There was an increase in latent period, increase in rate of tension development, potentiation of peak twitch amplitude, and a prolongation of the relaxation period. Lanthanum produced no change of the resting potential, hut caused a graded reduction in rate of rise, amplitude, and rate of fall of the action potential. At concentrations of the metal ion exceeding 0.3 mM, the mechanical response was complicated by impaired excitation, leading to a diminution of the twitch response and failure to produce a fused tetanus. Exposure to still higher concentrations of lanthanum (≥ 0.5 mM) made the fibre electrically inexcitable. The lanthanum‐induced changes were completely reversible on removal of the metal ion from the bath. Lanthanum in a concentration of 0.1 mM could be used as a substitute for calcium to maintain a normal resting membrane potential and twitch response. The results suggest that lanthanum and calcium act on a common site in the membrane. The alterations in twitch kinetics produced by lanthanum are discussed in relation to changes of action potential and mechanical threshold.
Interaction between Prostaglandins and Calcium Ions on Noradrenaline Release from the Stimulated Guinea Pig Vas Deferens
Authors: Hedqvist Per 
Published: December 2008

AbstractIn the superfused guinea pig vas deferens, prostaglandin E2 (1–10 ng/ml) caused a dose dependent and reversible depression of the overflow of 3H‐noradrenaline in response to trans‐mural stimulation. Increasing the calcium concentration in the superfusion medium from 1.8–5.4 mM enhanced the overflow of 3H‐noradrenaline and reversed the inhibitory effect of prostaglandin E2. Closely similar effects were obtained with prostaglandin E1. In the presence of elevated calcium (5.4 mM), prostaglandin E2 was still inhibitory, but the dose‐effect curve was significantly shifted to the left, making the compound less effective in inhibiting the overflow of 3H‐noradrenalhe. The results are compatible with, and add further weight to the consideration that prostaglandins of the E series restrict the release of noradrenaline from sympathetic nerves by inhibiting the influx of calcium ions into the neuron.
The Effect of Water Diuresis and Antidiuretic Hormone on the Regional Renal Red Cell Flow
Authors: Persson A. E. G. , Schnermann J. , Ulfendahl H. R. , Wolgast M. , Wunderlich P. 
Published: December 2008

AbstractThe possible role of the renal medullary hemodynamics in the formation of hypertonic and hypotonic urine was examined in 9 mongrel dogs, using an indicator‐dilution technique with 32‐P labelled red cells internal detection with small needle‐shaped semiconductor detectors. The red cell flow was estimated froma) the mean transit time calculated by dividing the area of the indicator‐dilution curve by the peak activity andb) the regional red cell volume determined as the ratio of intrarenal equilibrium activity to red cell equilibrium activity in whole blood.In water diuresis, as induced by 200–400 ml of a hypotonic saline‐glucose solution, the red cell flow showed a small and barely significant increase estimated at 19 %, 18 % and 10 % for the cortical, outer medullary and inner medullary circulations, respectively. After the administration of antidiuretic hormone at a rate of 1.5 mU/min and kg the cortical and outer medullary red cell flows (but not the inner medullary) were significantly reduced towards the control values. It is concluded that the conditions of water diuresis and antidiuresis as due to the action of ADH are not accompanied by marked changes in the renal medullary blood flow.
Muscle Glycogen Utilization during Exercise after Physical Training
Authors: Karlsson Jan , Nordesjö Lars‐Olof , Saltin Bengt 
Published: December 2008

Abstract5 male subjects exercised at a mean oxygen uptake of 2.3 1× min‐1 (≅ 65 % of Vo2, max) before and after 2 months of physical training for 90 min and 120 min, respectively. Mean maximal oxygen uptake increased by 11 % (p < 0.05), and the mean R‐value during the submaximal work decreased from 0.93 to 0.89 (p < 0.01). Plasma levels for FFA and glucose during exercise were unaffected by training. The mean rate of muscle glycogen breakdown in the thigh between 20 and 90 min of prolonged work could be estimated to be 0.66 before and 0.41 mmol glucose units × kg‐1 wet muscle × min‐1 after training (p < 0.01). Part of the reduced glycogen utilization could be explained by a less pronounced lactate production in the trained stage. It is concluded that a short period of physical conditioning results in a decredse in glycogen utilization and an enhanced fat oxidation.
Vascular and Metabolic Effects of Theophylline, Dibuturyl Cyclic AMP and Dibuturyl Cyclic GMP in Canine Subcutaneous Adipose Tissue in situ1
Authors: Fredholm Bertil B. 
Published: December 2008

AbstractIn canine subcutaneous adipose tissue theophylline (2×10‐‐4M), cAMP and ATP (10‐‐5M), and DBcAMP (8×10‐‐4M) increased blood flow by by approximately 100 per cent. These compounds also antagonized sympathetic vasoconstriction. Theophylline and DBcAMP increased glycerol release dose‐dependently, while cAMP and ATP were ineffective up to I mM. Theophylline (0.4–0.8 mM) potentiated the lipolytic effect of nerve stimulation, while 2–8 mM apparently caused maximal stimulationPer se. DBcAMP did not affect FFA release following nerve stimulation, while DBcGMP potentiated. The apparent rate of re‐esterification, glucose uptake and lactate release was decreased by theophylline. DBcAMP (0.1–0.4 mM) had no effect on these parameters, while DBcGMP at the same concentration decreased re‐esterification and lactate release. Stimulated overflow of3H from tissues prelabelled with L‐3H‐noradrenaline was reduced to 50 per cent by ATP (0.1–0.4 mM), but was unaffected by DBcAMP and DBcGMP at the same concentration. The results support the view that cAMP mediates the metabolic actions of sympathetic nerve stimulation in canine subcutaneous adipose tissue. The relationship between cAMP and vascular reactions may be more complex.
The Role of Blood Platelets in Pulmonary Responses to Microembolization with Barium Sulphate
Authors: Bø G. , Hognestad J. , Vaage J. 
Published: December 2008

AbstractIntravenous administration to cats of a barium sulphate suspension caused a temporary and marked increase in the pulmonary vascular resistance. On repeated infusions there was a gradual decrease in this pulmonary response. At the same time there occurred a marked fall in the number of circulating blood platelets. Another group of cats were made thrombocytopenic beforehand by treatment with anti‐platelet serum In such cats infusions of barium sulphate gave no or very weak pulmonary vascular response. The presence of a certain number of circulating blood platelets is thus necessary for barium sulphate infusions to have their marked effects on the pulmonary circulation. It appears that the essential effect of barium sulphate in this connection is to cause blood platelet alterations, with aggregation and probably a subseqent release of vasoactive materials.
Aspects of the Relative Roles of Peripheral Vasoconstriction and Vagal Bradycardia in the Establishment of the “Diving Reflex” in Ducks
Authors: Blix Arnoldus Schytte , Gautvik Eva Løwer , Refsum Helge 
Published: December 2008

AbstractThe effects of α‐adrenergic (Phenoxybenzamine) and parasympathetic (Atropin) blockade on the cardiovascular response to diving in the duck has been studied. With no significant reduction in the immediate, slight fall in heart rate, a‐adrenergic blockade caused peripheral vasodilatation, and virtually abolished the more delayed phase of profound bradycardia during diving. Atropinization eliminated both elenients of the diving bradycardia., while the arterial and venous pressure greatly increased, suggesting that intense activation of the vasoconstrictor fibres was maintained during submersion. It is concluded that the gradual but profound intensification of the initial, slight bradycardia in the dividing duck is a matter of a secondary reflex adjustment to the pressure level.
Human Muscle Spindle Discharge during Isometric Voluntary Contractions. Amplitude Relations between Spindle Frequency and Torque
Authors: Vallbo A. B. 
Published: December 2008

AbstractDuring isometric voluntary contractions, the impulse frequency in muscle spindle afferents was analysed in relation to the contraction intensity in man. Single unit impulses from the finger flexor muscles were recorded with percutaneously inserted tungsten needle electrodes from the median nerve. The spindle frequency increased with the contraction intensity. For very weak contractions the increase was steep but levelled off to attain an average slope of 32.8 ips/Nm at the metacarpo‐phalangeal joint for the primaries and 22.8 ips/Nm for the secondaries when the muscles to a single finger were activated. The close relation between spindle frequency and torque suggests parallel modulations of the skeletomotor and the fusimotor outputs during voluntary contractions. The dominating type of fusimotor outflow was of the static type but clear indications of increased dynamic fusimotor outflow were also seen. Quantitative considerations of the spindle frequency as a function of contraction intensity and as a function of muscle length suggest that the muscle spindles and their central connections do not constitute a very powerful mechanism for holding the muscle at constant length when the load varies.
Cerebral Blood Flow and Cerebral Metabolic Rate for Oxygen in Rats with Porta‐Caval Anastomosis
Authors: Eklöf Bo , Holmin Torsten , Jóhannsson Halldór , Siesjö Bo K. 
Published: December 2008

AbstractRegional cerebral blood flow and cerebral arteriovenous differences in oxygen content were studied in rats provided with a porta‐caval shunt. The arteriovenous oxygen differences decreased, while cerebral blood flow was unchanged. It is concluded that rats with a porta‐caval anastomosis have a reduction in cerebral metabolic rate for oxygen, possibly due to reduced functional demands.
Pharmacological Exposure of Components in the Autonomic Control of the Diving Reflex
Authors: Andersen Harald T. , Blix Arnoldus Sch. 
Published: December 2008

AbstractThe autonomic mechanisms controlling cardio‐vascular adjustments to diving have been studied in ducks using drugs which block adrenergic a‐receptors (phentolamine) or deplete catechol‐amine stores (reserpine). In animals thus treated there was a marked change in the cardiovascular reflex pattern upon diving. The vasoconstrictor response regularly seen in normal, submerged animals appeared to be abolished, and the diving bradycardia was only poorly developed. As a consequence, the treated animals had lost their capability to endure submersion for prolonged periods of time, the catecholamine depleter being more effective in this respect than the α‐receptor blocking agent. However, if noradrenaline was administered to a submerged animal pre‐treated with reserpine, peripheral vasoconstriction and bradycardia took place momentarily. It is concluded that the initial, quick slowing of the heart, which takes place upon submersion, results from an immediate parasympathetic activity associated with the reflex apnoea. The profound diving bradycardia gradually developing may be due to baroreceptor stimulation related to the peripheral vasoconstriction.
Drug Effects on Isolated Artery Strips from Two Teleosts, Gadus morhua and Salmo gairdneri
Authors: Holmgren Susanne , Nilsson Stefan 
Published: December 2008

AbstractThe presence of adrenergic and cholinergic receptors in the celiac arteries of the cod,Gadus morhua, and the rainbow trout,Salmo gairdneri, has been investigated. Affinities and intrinsic activities of different catecholamines and acetylcholine have been determined from cumulative dose‐response curves. The pD2‐value for acetylcholine was 6.62 ± 0.20 in the rainbow trout arteries, while the cod arteries only responded to acetylcholine in concentrations of 10‐‐2M or more. In both species the potencies of the catecholamines producing contraction of the arteries were in the order adrenaline > noradrenaline > phenylephrine, while isoprenaline did not contract the preparations. In cod arteries competitive antagonism was obtained with yohimbine (pA2= 7.3), phentolamine (pA2= 8.0) and propranolol (pA2= 6.1), while phenoxybenzamine produced non‐competitive blockade of the response to noradrenaline (pM50= 6.9). It is concluded that although the rainbow trout celiac artery could possess double innervation, it is unlikely that a cholinergic vasomotor innervation plays any role in regulating the cod celiac artery. A solely adrenergic alpha receptor mediated innervation is therefore proposed for the cod celiac artery.
Differences in Recruitment Order and Discharge Pattern of Motor Units in the Early and Late Flexion Reflex Components in Man
Authors: Grimby Lennart , Hannerz Jan 
Published: December 2008

AbstractThe recruitment order of motor units in the normal and pathological flexion reflex in man was studied by electromyographic techniques. The following findings were made: (1) the recruitment order is different in the early, phasic and in the late, tonic flexion component; (2) this difference is eliminated so that the recruitment order of the late reflex component is also used in the early reflex component if the motoneurone pool is subliminally facilitated in advance; (3) the first motor unit in the early component of the non‐facilitated pathological flexion reflex tends to discharge a higher frequency than does the first motor unit in the late reflex component. It is suggested that short reflex arcs may favour phasic motoneurones while long reflex arcs and long‐lasting states of facilitation favour tonic motoneurones.