Inhalation anesthesia in adult cattle

An inhalation technique was used for anesthesia during ileal cannulation in five adult cows. Following sedation with intravenous acepromazine, anesthesia was induced intravenously with thiopental sodium in 5% glyceryl guaiacolate solution. Endotracheal intubation was performed and anesthesia maintained with halothane in oxygen via a circle system with a precision vaporizer. In all cases, induction was smooth and no difficulties were experienced during the maintenance of anesthesia. Total anesthesia time was 1.5 to 2.5 hours. Following completion of the surgical procedure, which was performed with the animal in left lateral recumbency, each cow was rolled to a sternal position and supported, if necessary. The endotracheal tube was left in place, with oxygen administration continued, until the animal was able to swallow. Recoveries were rapid and all animals were ambulatory within 30 minutes after completion of the surgery. The only post-operative complication due to anesthesia was transient mouth soreness in two cases, attributed to the use of a mouth speculum during intubation.     

Enzyme recovery during gas/liquid two-phase flow microfiltration of enzyme/yeast mixtures

The effect of a gas/liquid two-phase flow on the recovery of an enzyme was evaluated and compared with standard crossflow operation when confronted with the microfiltration of a high-fouling yeast suspension. Ceramic tubular and flat sheet membranes were used. At constant feed concentration (permeate recycling) and transmembrane pressure, the results obtained with the tubular membrane were dependent on the two-phase flow pattern. In comparison with single-phase flow performances at the same liquid velocity, the enzyme transmission was maintained at a high level with a bubble flow pattern but it decreased by 70% with a slug flow, whatever the flow rate ratio. Identical results were obtained with flat sheet membranes: for the highest flow rate ratio, the enzyme transmission was reduced by 70% even though the permeate flux was improved by 240%. During diafiltration experiments with the tubular membrane, it was found that a bubble flow pattern led to a 13% higher enzyme recovery compared to single-phase flow conditions, whereas with a slug flow the enzyme recovery was strongly reduced. With bubble flow conditions, energy consumption was minimal, confirming that this flow pattern was the most suitable for enzyme recovery.     

Influence of prior and visual information on eye movements in amblyopic children

This study analyzed the characteristics of pursuit and assessed the influence of prior and visual information on eye velocity and saccades in amblyopic and control children, in comparison to adults. Eye movements of 41 children (21 amblyopes and 20 controls) were compared to eye movements of 55 adults (18 amblyopes and 37 controls). Participants were asked to pursue a target moving at a constant velocity. The target was either a ‘standard’ target, with a uniform color intensity, or a ‘noisy’ target, with blurry edges, to mimic the blurriness of an amblyopic eye. Analysis of pursuit patterns showed that the onset was delayed, and the gain was decreased in control children with a noisy target in comparison to amblyopic or control children with a standard target. Furthermore, a significant effect of prior and visual information on pursuit velocity and saccades was found across all participants. Moreover, the modulation of the effect of visual information on the pursuit velocity by group, that is amblyopes or controls with a standard target, and controls with a noisy target, was more limited in children. In other words, the effect of visual information was higher in control adults with a standard target compared to control children with the same target. However, in the case of a blurry target, either in control participants with a noisy target or in amblyopic participants with a standard target, the effect of visual information was larger in children.

     

Demonstration of an androgen receptor in rat pancreas.

[1,2,6,7-3H]Testosterone (250 muCi) was administered to castrated male rats; after 30 min a labelled testosterone-receptor protein complex with a pI of 5.1 was recovered from the pancreatic cytosol. A labelled testosterone-receptor complex with an identical pI was also extracted from the nuclear fraction of rat pancreas after incubation of minced pancreatic tissue with 0.1 muM-]1,2,6,7-3H]testosterone for 30 min at 37 degrees C. Studies in vitro showed that [1,2,6,7-3H]testosterone was bound to a receptor protein focusing at a pI of 5.1 and with a Kd of 2 nM and a number of binding sites of 4.7 fmol/mg of protein in castrated male rats. The testosterone-receptor complex sedimented at 3.5 S in high-salt sucrose-density gradients, was excluded from Sephadex G-200 and Ultragel ACA-34, was stable towards treatment with dextran-coated charcoal, was relatively sensitive to heat, and was stable to treatment with deoxyribonuclease and ribonuclease, but was sensitive to treatment which proteinase. It is suggested that the pancreatic androgen receptor, which was also present in castrated female rats, may play a role in sex-steroid regulation of pancreatic function.     

Usefulness of Glucokinase from Bacillus stearothermophilus for the Enzymatic Measurement of Magnesium in Human Serum

(22R,23R,24S)-3α,5-Cyclo-22,23-diacetoxy-5a-ergostan-6-one (2b) is a new key intermediate of some naturally occurring brassinosteroids such as brassinolide (la), castasterone (lb), teasterone (lc) and typhasterol (Id). The cycloketone 2b was prepared in 10 steps via (22R,23R,24S)-6p- benzyloxy-3a,5-cyclo-22,23-dihydroxy-5a-ergostane (5) from stigmasterol. 2b was treated with a catalytic amount of /7-toluenesulfonic acid and sodium bromide to give an enone (7b), which was oxidized with osmium tetroxide and derived to give a 2a,3a-acetonide (8b). 8b was easily separated from its isomer by the use of silica gel column chromatography. 8b was oxidized with tri- fluoroperacetic acid and deacetylated to give la. 8b was deacetylated and deacetonized to give lb. 2b was treated with dilute sulfuric acid in acetic acid to give a 3/^-acetate (10). 10 was treated with sodium hydroxide to give lc. 2b was treated with hydrobromic acid to give a 3/i-bromide (12), which was treated with silver acetate to give a 3a-acetate (13). 13 was treated with sodium hydroxide to give Id.     

Monoclonal antibody radiopharmaceuticals: cationization,pegylation, radiometal chelation,pharmacokinetics, and tumor imaging

The 528 murine monoclonal antibody (MAb) to the human epidermal growth factor receptor (EGFR) was sequentially cationized with hexamethylenediamine and conjugated with diethylenetriaminepentaacetic acid (DTPA) as a potential antibody radiopharmaceutical for imaging EGFR-expressing cancer. The cationized 528 MAb was characterized with isoelectric focusing and electrophoresis, and an immunoradiometric assay, which showed the affinity of the 528 MAb for the human EGFR was retained following cationization. The native or cationized 528 MAb, labeled with (111)In, was injected intravenously in scid mice bearing human U87 flank tumors, which express the EGFR, and tumor imaging was performed with both external detection in live animals and with whole body autoradiography. However, the tumor signal was not increased with the cationized MAb, relative to the native MAb, and this was due to a serum inhibition phenomenon that was confirmed by a pharmacokinetics analysis in control mice. In an attempt to block the serum inhibition, the cationized 528 MAb was pegylated with 2000 Da poly(ethylene glycol), and the cationized/pegylated MAb was conjugated with DTPA and labeled with (111)In. However, a pharmacokinetics analysis showed the pegylation did not reverse the serum inhibition of the cationic charge on the MAb. These studies describe methods for reformulating monoclonal antibodies to develop improved radiopharmaceuticals, but show that radiolabeling a cationized MAb with DTPA produces a serum neutralization of the initial cationization modification.     

Determination of remifentanil in human plasma by liquid chromatography-tandem mass spectrometry utilizing micro extraction in packed syringe (MEPS) as sample preparation

Remifentanil is a synthetic short-acting opioid with a short half-life that is being used during anaesthesia of small children. In this work an LC-MS/MS method for remifentanil quantification in 20 μL volume of human plasma was developed and validated in connection with a clinical study on neonatal children. Sample preparation was performed with micro extraction in packed syringe (MEPS), which is a miniaturization of solid phase extraction. For this method a mixed phase sorbent M1 (C8, cation exchange), and a protocol for basic compound extraction was followed. Remifentanil-(13)C(6) was used as internal standard. For chromatographic separation, a C18 analytical column with gradient elution was used with mobile phase consisting of aqueous 0.1% formic acid and methanol. The total analysis time was 5.0 min and the measuring range was between 0.05 and 50 ng/mL. Precision and accuracy were with acceptance criteria of ±15%. Plasma samples were stable for 5 weeks at -20°C and for 4h at room temperature while 50% was lost after 24h. This method was successfully applied for remifentanil determination in clinical samples and results agreed with a reference method. With this method using MEPS, a low limit of quantification and much reduced sample volume was obtained as compared with previous methods.     

大黄鱼快长相关微卫星标记的筛选与验证

为了筛选与大黄鱼生长性状紧密相关的分子标记,并对这些标记的有效性进行鉴定,研究以大黄鱼家系和群体为材料,经标记筛选、两次验证共三个步骤,找到2个与大黄鱼生长性状紧密相关的微卫星标记:LYC0088和LYC0143,其中LYC0088与体高、体质量均极显著相关（P0.01）,与体长显著相关（P0.05）,LYC0143与体长和体质量显著相关（P0.05）,与体高的相关性极显著（P0.01）。LYC0088与LYC0143位点的优势等位基因分别为E、A,优势等位基因型均为AB,优势等位基因型组合为AB/AB,两个位点呈加性效应。该结果为开展大黄鱼分子标记辅助育种提供了有价值的遗传标记。       

Attractiveness of the maleAcheta domestica calling song to females

Summary FemaleAcheta domestica did not discriminate between pairs of model calling songs (CSs) which differed only in syllable period (SP; Fig. 1). The females selected the louder CS (Fig. 2) or the CS with a faster chirp rate (CR; Fig. 3) when presented with pairs of otherwise identical CSs. A CS with an SP of 50 ms (modal for the male's CS) was preferred when it was 5 dB louder than one with a 60-ms SP while a CS with a 60-ms SP was only consistently chosen when it was 10 dB louder than a CS with a 50-ms SP (Fig. 4). A more intense CS was preferred by the females regardless of whether its CR was faster or slower than that of the CS produced at a lower intensity (Fig. 6). When CSs with SPs of 50 or 60 ms had several different CRs, the females that made a significant choice preferred a CS with a 50-ms SP regardless of whether it was produced at a faster or slower CR (Figs. 7, 8). No significant selection between CSs with 40- and 50-ms SPs resulted when they were produced at different intensities (Fig. 5) or CRs (Fig. 9). Females only significantly chose a CS with a 50-ms SP over those with 40 ms SPs when the 50-ms-SP CS was louder and produced at a different CR (Fig. 10). From these results, it was apparent that SP, intensity, and CR all influenced a female's choice of a CS, and thus the male producing it. However, our results indicate that SP was the most important feature influencing the female's choice and that intensity was more effective than CR.Abbreviations CR chirp rate - CS calling song - POD polar orientation diagram - SP syllable period     

On the interactions of catalase with subcellular structure

The interaction of mouse liver catalase with subcellular membranes was studied, and an ionic interaction with a variety of membranes, including those derived from the microsomes, was observed. The interaction with microsomal membranes was found to be abolished by pre-treatment of catalase with neuraminidase, indicating a functional significance for catalase-bound sialic acid. Catalase activity was found to be enhanced when bound to membranes, and evidence for a weak association of catalase with peroxisomal structure in mouse liver was also obtained. It is concluded that mouse liver catalase has a capacity to bind to a variety of subcellular membranes in vivo and that this interaction may be consistent with a general protective role for the enzyme, as well as being compatible with a model of peroxisomal biogenesis which involves the interaction of catalase with microsomal membranes.Abbreviations LGF Large Granule Fraction     

Isolation and characterization of human erythrocyte insulin receptors

The noncovalently associated 125I-insulin-receptor complex was isolated from human erythrocyte membranes after allowing 125I-insulin to interact with the membranes followed by extraction of the 125I-insulin-receptor complex with Triton X-102 or, alternatively, by complete solubilization of the membranes with sodium dodecyl sulfate (SDS), removal of SDS, and then treatment of the solubilized sample with 125I-insulin. Sepharose CL-6B column chromatography of the 125I-insulin-receptor complex obtained by both of the above procedures yielded a highly radioactive 140,000-Da complex which was dissociated into small peptides when subjected to SDS-polyacrylamide gel electrophoresis. In contrast, when the 125I-insulin-treated membrane sample was extracted with Triton X-102, purified by DEAE-Sephacel ion exchange chromatography, covalently cross-linked with disuccinimidyl suberate, and then subjected to SDS-polyacrylamide gel electrophoresis, a highly radioactive component with Mr = 53,000 was obtained. On the other hand, when the Triton X-102-solubilized membrane receptor sample was fractionated by DEAE-Sephacel ion exchange chromatography, complexed with 125I-insulin, covalently crosslinked, and then applied to a Sepharose CL-6B column, a 95,000-Da complex with high specific radioactivity was obtained. Upon SDS-polyacrylamide gel electrophoresis, the 95,000-Da complex was dissociated into a 53,000-Da component which appeared identical with that obtained from the receptor complex described above which was obtained by direct interaction of the membranes with 125I-insulin.     

Optical bio-sniffer for ethanol vapor using an oxygen-sensitive optical fiber

An optical bio-sniffer for ethanol was constructed by immobilizing alcohol oxidase (AOD) onto a tip of a fiber optic oxygen sensor with a tube-ring, using an oxygen sensitive ruthenium organic complex (excitation, 470 nm; fluorescent, 600 nm). A reaction unit for circulating buffer solution was applied to the tip of the device. After the experiment in the liquid phase, the sniffer-device was applied for gas analysis using a gas flow measurement system with a gas generator. The optical device was applied to detect the oxygen consumption induced by AOD enzymatic reaction with alcohol application. The sensor in the liquid phase was used to measure ethanol solution from 0.50 to 9.09 mmol/l. Then, the bio-sniffer was calibrated against ethanol vapor from 0.71 to 51.49 ppm with good gas-selectivity based on the AOD substrate specificity. The bio-sniffer with the reaction unit was also used to monitor the concentration change of gaseous ethanol by rinsing and cleaning the fiber tip and the enzyme membrane with buffer solution.     

Alteration of birefringence signals from squid giant axons by intracellular perfusion with protease solution

The optical signal, arising from a transient birefringence change associated with excitation, was recorded from a squid giant axon together with the membrane potential change, and the effect of removal of the axoplasm on the optical signal was examined. In an unperfused axon, repetitive stimulation at a frequency of about 100 Hz produced two kinds of optical response. The initial response had a brief, spike-like time course and was elicited by each stimulating pulse. The delayed response had a slow time course and the sign of decreased light intensity, and summated with repetitive stimulation. Most of the axoplasm was removed from interior of the axon by intracellular perfusion with solutions containing pronase at a concentration of 0.1 mg/ml. The delayed response could selectively be eliminated by perfusion with a pronase-containing solution for 2–8 min. The result was interpreted as showing that the delayed birefringence signal originates from axoplasm when its gel structure was transiently disturbed by an increased Ca²⁺ influx associated with excitation. When perfusion was further continued the duration of the action potential started increasing and often a prominent after-depolarization appeared. At this stage the initial optical response was again followed by a large show signal with the sign of increased light intensity. This reversed delayed response was tentatively assumed to originate from the membrane with some remaining axoplasm, but its cause is still not understood.     

The binding of 1,N6-etheno-NAD to bovine liver glutamate dehydrogenase

The interaction of thrombin and platelets was studied with a heterobifunctional photoactivable crosslinking agent. Radiolabeled thrombin that was modified with ethyl-N-5-azido-2-nitrobenzoylaminoacetimidate formed two types of complex with platelet proteins: platelet-associated complexes and supernatant complexes. The platelet-associated complexes formed within 20 s. Autoradiography after electrophoresis with sodium dodecyl sulfate indicated that these complexes had apparent masses of 210, 185, 155 and 125 kDa. Formation of the complexes was blocked by hirudin; this is consistent with crosslinking that was a direct consequence of the binding of thrombin to a specific receptor, since hirudin blocks thrombin-induced platelet activation and the saturable binding of thrombin to platelets. The labeled supernatant complex had an apparent mass of about 490 kDa. It also formed in the supernatant solution of platelets after activation with a divalent cation ionophore, suggesting a complex of thrombin with a secreted protein. The supernatant complex did not involve fibrinogen or alpha 2-macroglobulin, but a similar complex was formed with partially purified secreted glycoprotein G (thrombin-sensitive protein, thrombospondin). Formation of the complex was blocked by hirudin. A similar complex was formed after prolonged (1 h) incubation without photoactivation. It is concluded that thrombin forms high-affinity, hirudin-sensitive complexes with secreted glycoprotein G, as well as with platelet surface proteins.     

Relationships among purine nucleoside metabolism, adenosine triphosphate catabolism, and glycolysis in human erythrocytes.

In human erythrocytes incubated with both naturally occurring purine nucleosides and with a variety of purine nucleoside analogs, ATP catabolism was accelerated and lactate accumulation was increased. Tubercidin was a particularly potent inducer of ATP catabolism. In cells incubated with tubercidin, the major route of adenylate metabolism was deamination, whereas in cells incubated with deoxyglucose, the major pathway was dephosphorylation.     

Soybean oil methyl esters preparation using NaX zeolites loaded with KOH as a heterogeneous catalyst

The transesterification of soybean oil with methanol to methyl esters was carried out using NaX zeolites loaded with KOH as a solid base catalyst. Best result was obtained with NaX zeolite loaded with 10% KOH, followed by heating at 393 K for 3 h. When the transesterification reaction was carried out at reflux of methanol (338 K), with a 10:1 molar ratio of methanol to soybean oil, a reaction time of 8 h and a catalyst amount of 3 wt.%, the conversion of soybean oil was 85.6%.     

Stacking of safranine in liposomes during valinomycin-induced efflux of potassium ions.

Liposomes were prepared from phosphatidylcholine and cardiolipin in a KCl medium and suspended in a choline chloride medium with safranine. When efflux of K+ was induced by valinomycin, spectral shifts characteristic of stacking were observed. Ca2+ inhibited the rate of stacking in a competitive manner with a Ki of about 200 muM, while La3+ was about 10 times more potent. When liposomes were prepared from phospholipids with a higher ratio of cardiolipin to phosphatidylcholine the inhibition was more potent. No effect on the stacking phenomena was seen when CA2+ was added after the stacking was completed. When CA2+ or an organic cation with four charges, spermine was trapped in the intraliposomal compartment, no significant change in the rate of stacking was seen. However, the extent of stacking was decreased. It is suggested that safranine is driven by a diffusion potential to a site that is inaccessible to CA2+ in the medium, presumably to the inner boundaries of the liposomal membranes.