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The effect of acupuncture on anxiety and neuropeptide Y expression in the basolateral amygdala of maternally separated rats.

Recent studies have suggested that maternally deprived rats exhibit anxiogenic-like behavior when exposed to stress in later life. Neuropeptide Y (NPY) is involved in the regulation of various physiological functions such as the expression of anxiety. Female Wistar rat pups were separated from their mothers for 3h daily from postnatal days 3 (P3) to 14 (P14). Acupuncture groups were treated with acupuncture at Shenmen (HT7) or Zusanli (ST36) on alternate days from P50 to P62. Their anxiety-like behavior was evaluated using an elevated plus-maze at P62, and then NPY immunohistochemistry in the basolateral amygdala (BLA) was performed. Rats exposed to maternal separation (MS) were less likely to explore the open arms of the plus-maze compared to control rats that were not exposed to MS. Among maternally separated groups, the percentage of time spent in the open arms was significantly increased in the HT7 acupuncture group, but not the ST36 acupuncture group, compared to MS group. In accordance with this behavior, the numbers of NPY-immunoreactive cells in the BLA were lower in the MS group compared to the control group. Among maternally separated groups, the numbers of NPY-immunoreactive cells in the BLA were significantly higher in the HT7 acupuncture group, but not higher in the ST36 acupuncture group, compared to MS group. These findings suggest that acupuncture treatment might reduce anxiety-like behavior in adult rats following maternal separation by modulating the NPY system in the amygdala.

Acupuncture Therapy↗

Maternal separation alters serotonergic transporter densities and serotonergic 1A receptors in rat brain.

RATIONALE: The basic mechanisms underlying the association between early life maternal separation and adulthood psychiatric disorders are largely unknown. One possible candidate is the central serotonergic system, which is also abnormal in psychiatric illnesses. Neuroadaptational changes in serotonergic transporter and serotonergic 1A receptors may underlie links between early life stress and adulthood psychiatric disorders. OBJECTIVE: The aim of this study was to investigate the consequences of a rat model of maternal separation on serotonergic transporter and serotonergic 1A receptor densities and function in adult rat forebrain. METHODS: Rat pups were separated from dams from postnatal day 2 to postnatal day 14, each day, for zero time, 15 min and 180 min to determine the time-course of effects. A non-handled group was added to control for the effects of handling by an experimenter compared with the animal facility-reared group. Quantitative [(125)I]3beta-(4-iodophenyl)tropan-2beta-carboxylic acid methyl ester and [(125)I]-mPPI autoradiography was used to determine serotonergic transporter and serotonergic 1A densities, respectively. Adult rats were challenged with saline or serotonergic 1A agonist (+) 8-hydroxy-2-(di-n-propylamino)tetralin, 0.4 mg/kg, s.c.) and plasma adrenocorticotropic hormone and corticosterone were determined. RESULTS: serotonergic transporter and serotonergic 1A densities were significantly lower in the non-handled group in the paraventricular, arcuate, dorsomedial and ventromedial nuclei of the hypothalamus. The non-handled group also displayed lower serotonergic transporter and serotonergic 1A densities in the basolateral anterior, basolateral ventral and basomedial amygdaloid nuclei. Serotonergic transporter densities were also decreased in the CA3 area of the hippocampus in the non-handled group. In contrast, the maternal separation 15 min group displayed the highest serotonergic transporter and serotonergic 1A densities in the basomedial nucleus of amygdala, basolateral anterior nucleus of amygdala, basolateral ventral nucleus of amygdala and basomedial nucleus of amygdala amygdaloid nuclei. CONCLUSIONS: Early life maternal separation and the extent of handling can alter adult brain serotonergic transporter and serotonergic 1A levels and function in the forebrain. Alterations in these serotonergic systems by early rearing conditions might increase vulnerability for behavioral disorders in adulthood.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

A simple and selective method for the separation of Cu radioisotopes from nickel.

Separation of copper radioisotopes from a nickel target is normally performed using solvent extraction or anion exchange rather than using cationic exchange. A commonly held opinion is that cationic exchangers have very similar thermodynamic complexation constants for metallic ions with identical charges, therefore making the separation very difficult or impossible. The results presented in this article indicate that the selectivity of Chelex-100 (a cationic ion exchanger) for Cu radioisotope and Ni ions not only depends on the thermodynamic complexation constant in the resin but also markedly varies with the concentration of mobile H+. In our developed method, separation of copper radioisotopes from a nickel target was fulfilled in a column filled with Chelex-100 via controlling the HNO3 concentration of the eluent, and the separation is much more effective, simple and economical in comparison with the common method of anion exchange. For an irradiated nickel target with 650 mg Ni, after separation, the loss of Cu radioisotopes in the nickel portion was reduced from 30% to 0.33% of the total initial radioactivity and the nickel mixed into the radioactive products was reduced from 9.5 to 0.5 mg. This significant improvement will make subsequent labeling much easier and reduce consumption of chelating agents and other chemicals during labeling. If the labeled agent is used in human medical applications, the developed method will significantly decrease the uptake of Ni and chelating agents by patients, therefore reducing both the stress on human body associated with clearing the chemicals from blood and tissue and the risk of various types of acute and chronic disorder due to exposure to Ni.

Chromatography, Ion Exchange↗

Effects of maternal separation on voluntary ethanol intake and brain peptide systems in female Wistar rats.

In previous studies, changes in adult ethanol intake after early environmental experiences, such as short and prolonged maternal separation, have been described in male rats. The aim of this study was to further investigate long-term effects of maternal separation on voluntary ethanol intake as well as brain opioid and nociceptin/orphanin FQ (N/OFQ) peptides in female Wistar rats. During postnatal days (PNDs) 1-21, rat pups were subjected to 15 min (MS15) or 360 min (MS360) of daily maternal separation, or were kept under normal animal facility rearing (AFR) conditions. At 10 weeks of age, ethanol intake was measured using a two-bottle free choice paradigm and dynorphin B (DYNB), Met-enkephalin-Arg6-Phe7 (MEAP) and N/OFQ levels were analyzed. MS15 resulted in changes in hypothalamus (DYNB), medial prefrontal cortex and nucleus accumbens (MEAP), and amygdala (N/OFQ). MS360 induced alterations in medial prefrontal cortex (MEAP) and amygdala (N/OFQ). MS15 and MS360 had no effect on ethanol intake. However, 4 weeks of ethanol intake affected peptide levels differently in MS15, MS360 and AFR rats and resulted in attenuation of the separation-induced differences. These results show that even though maternal separation has no effect on voluntary ethanol intake in female rats, the ethanol-induced effects on peptide levels depend on the early environmental setting.

Alcohol Drinking↗

Adult life behavioral consequences of early maternal separation are alleviated by escitalopram treatment in a rat model of depression.

In order to study the gene-environment interaction as well as investigate prophylactic/ameliorative effects of early intervention on development of adult life psychopathology, we superimposed maternal separation on an animal model of depression the Flinders Sensitive Line (FSL) rats and their controls the Flinders Resistant Line (FRL) rats and studied behavior following treatment with escitalopram. Animals were maternally separated for 180 min/day from postnatal day 2 (PND 2) to 14. The control groups were left undisturbed. Treatment with escitalopram or vehicle admixed to food pellets was commenced on PND 43 and continued until PND 73. The Porsolt swim test was carried out on PND 65. Baseline FRL/FSL differences in body weight and swim duration, considered to be an inverse index of depression, were found (p's<0.001). In the FSL, maternal separation further decreased swim duration (p<0.001) while the FRL strain was unaffected. Escitalopram had no effect in FRL, but increased swim duration in both maternally non-separated and separated FSL (p<0.05 and p=0.001; respectively). These results confirm the strain differences between the FSL and FRL and demonstrate that the long-term effects of early life adverse experience will to a significant degree depend on the genetic make-up of an individual. Finally, antidepressant treatment reversed behavioral abnormalities caused by genetic and environmental factors. This study highlights the importance of genetic factors in susceptibility to early life adverse events, and demonstrates the efficiency of early antidepressant treatment in reversing behavioral abnormalities, both those caused by genetic factors and by environmental factors.

Age Factors↗

Atresia ani with diphallus and separate scrota in a calf: a case report.

Atresia ani, a common genetic defect in animals, is often accompanied by urogenital defects in calves. This paper reports a case of atresia ani with diphallus and separate scrota in a calf. The calf was born with atresia ani; surgery (to open the anus) was performed 3 days after birth. No urogenital abnormalities were noticed until 4 months after birth. At that time, two separate scrota (each containing a testis) and a sac-like structure in the middle of two scrota, were visible. The gait was abnormal, with abduction of the hind limbs while walking. Additionally, the hind legs appeared wider than usual at the hip joints. Two weeks later, two peni (diphallia) was observed, each in a separate preputial sheath. The calf had a normal karyotype on cytogenetic examination. Plasma concentrations of testosterone at 5.5, 6, and 7 months of age were 3.5, 1.9, and 1.7 ng/ml, respectively. At necropsy (7 months of age), the prepuce was thick and the glans of the right penis was adhered to the prepuce. The left penis did not have a urethra or retractor penis muscles. The sac-like structure in the middle of the two scrota contained the urinary bladder and a loop of small intestine. The pubic bone had failed to fuse at the pelvic symphysis. In conclusion, this is the first reported case of atresia ani with diphallus, separate scrota, and pubic bone separation in a calf.

Animals↗

Biases in judgments of separation and orientation of elements belonging to different clusters.

If two demarcated dots are embedded in separate clusters of similar dots in off centre positions, their perceived separation is biased towards the separation between the centres of the clusters (Morgan, Hole, & Glennerster, 1990). We replicated these results and went on to determine whether a similar bias is present for orientation judgments, using a staircase method and a range of cluster orientations and separations. A complex pattern of biases was found including biases for targets at centroids. Orientation attraction towards tangents to the clusters seemed to be involved. We conclude that orientation is subject to different contextual constraints from separation, and that bias towards the edges of clusters needs to be included in models of position coding.

Adult↗

Removal of batteries from solid waste using trommel separation.

This paper describes the design and testing of a trommel for separation of batteries from solid waste. A trommel is a cylindrical separation device that rotates and performs size separation. It has also been used in areas such as municipal solid waste (MSW) processing, classifying construction and demolition debris, screening mass-burn incinerator ash and compost processing. A trommel has been designed based on size separation to separate household batteries from solid waste, which can then be used as feedstock for alternative applications of solid waste combustion, particularly where the metal content of the product is also a critical parameter, such as the Co-Co process for integrated cement and power production. This trommel has been tested with batches of university office and restaurant wastes against various factors. The recovery efficiency of batteries increases with decreasing inclination angle of the trommel and decreasing rotational speed. A physical characterization of the university solid waste has been performed with a 20-kg sample of the tested waste. It was found that there is a trend of decreasing recovery of batteries with increasing paper composition, and a trend of increasing recovery of batteries with increasing organic materials composition.

Manufactured Materials↗

Separate modifiability, mental modules, and the use of pure and composite measures to reveal them.

How can we divide a complex mental process into meaningful parts? In this paper, I explore an approach in which processes are divided into parts that are modular in the sense of being separately modifiable. Evidence for separate modifiability is provided by an instance of selective influence: two factors F and G (usually experimental manipulations) such that part A is influenced by F but invariant with respect to G, while part B is influenced by G but invariant with respect to F. Such evidence also indicates that the modules are functionally distinct. If we have pure measures MA and MB, each of which reflects only one of the parts, we need to show that MA is influenced by F but not G, while MB is influenced by G but not F. If we have only a composite measure MAB of the entire process, we usually also need to confirm a combination rule for how the parts contribute to MAB. I present a taxonomy of separate-modifiability methods, discuss their inferential logic, and describe several examples in each category. The three categories involve measures that are derived pure (based on different transformations of the same data; example: separation of sensory and decision processes by signal detection theory), direct pure (based on different data; example: selective effects of adaptation on spatial-frequency thresholds), and composite (examples: the multiplicative-factor method for the analysis of response rate; the additive-factor method for the analysis of reaction time). Six of the examples concern behavioral measures and functional processes, while four concern brain measures and neural processes. They have been chosen for their interest and importance; their diversity of measures, species, and combination rules; their illustration of different ways of thinking about data; the questions they suggest about possibilities and limitations of the separate-modifiability approach; and the case they make for the fruitfulness of searching for mental modules.

Humans↗

Liquid crystalline/gel state phase separation in docosahexaenoic acid-containing bilayers and monolayers.

The phase behavior of lipid mixtures containing 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (18:0, 22:6 PC) with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) was studied with bilayers using differential scanning calorimetry (DSC), and with monolayers monitoring pressure/area isotherms and surface elasticity, and lipid domain formation followed by epifluorescence microscopy. From DSC studies it is concluded that DPPC/18:0, 22:6 PC phase separates into DPPC-rich and 18:0, 22:6 PC-rich phases. In monolayers, phase separation is indicated by changes in pressure-area isotherms implying phase separation where 18:0, 22:6 PC is 'squeezed out' of the remaining DPPC monolayer. Phase separation into lipid domains in the mixed PC monolayer is quantified by epifluorescence microscopy using the fluorescently labeled phospholipid membrane probe, 1, 2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(lissamine rhodamine B sulfonyl). These results further describe the ability of docosahexaenoic acid to participate in lipid phase separations in membranes.

1,2-Dipalmitoylphosphatidylcholine↗

Development of separable electron spin resonance-computed tomography imaging for multiple radical species: an application to .OH and .NO.

A method of separable ESR-CT (electron spin resonance-computed tomography) imaging for multiple radical species was developed and applied to imaging of .OH and .NO. The algorithm was improved by combining filtered back-projection with a modified algebraic reconstruction technique to enhance accuracy and shorten calculation time. With this algorithm, spectral-spatial images of the phantom consisting of 3-carbamoyl-2,2,5,5,-tetramethylpyrrolidine-N-oxyl and 2-phenyl-4,4,5,5,-tetramethylimidazoline-3-oxide-1-oxyl could be obtained in different directions by rotating the spatial axis. The spatial function of individual radicals was extracted by each of the two methods from each spectral-spatial image. The separative 2D images of each radical were individually constructed using the spatial function obtained with the two methods. By comparing the separative images with the phantom sample, the algorithm for separable ESR-CT imaging was established. This ESR-CT technique was combined with L-band ESR spectroscopy and applied to the separative imaging of .OH and .NO, which were spin trapped with 5, 5-dimethyl-1-pyrroline-N-oxide (DMPO) and Fe(2+)-N-methyl-D-glucamine dithiocarbamate complex, respectively. The ESR signal of DMPO-OH decreased gradually during data acquisition, and the decrease was calibrated by extrapolating the signal intensity to the beginning of data sampling. Both the position and size of the individual images for .OH and .NO were in very good agreement with the findings for the sample.

Cyclic N-Oxides↗

Detailed mechanics of membrane-membrane adhesion and separation. II. Discrete kinetically trapped molecular cross-bridges.

In general, membrane-membrane adhesion involves specific molecular binding and cross-bridging reactions. The ideal, classical view is that near equilibrium the forces required to separate adhesive contacts are essentially equal to those induced in the membrane when the contact is formed. In contrast to the classical view, experimental observations often show that negligible levels of tension are induced by the adhesive contact even though the tension required to separate the contact is large enough to rupture the membrane. The deviation in tension levels associated with contact formation and separation appears to be due to the sparse distribution of strong molecular cross-bridges. Here, the mechanics of membrane-membrane adhesion and separation is developed for the case of discrete, kinetically trapped cross-bridges. The solution is obtained by numerical computation of the membrane contour that minimizes the total free energy (membrane elastic energy of deformation plus cross-bridge energies) in the contact zone. This solution is matched with the analytical solution for membrane stresses and geometry derived for the adjacent, unbridged zone. The results yield specific values of the macroscopic tension applied to the membrane in the plane region away from the contact zone and the microscopic angle at the edge of the contact zone. Two disparate values of the macroscopic tension are found: (a) the minimum tension required to separate the adherent membranes; and (b) the maximum tension induced in the membranes when the contact is formed (i.e., the level of tension at which the contact will just begin to spread). The results show that the deviation between these two tensions can be very large and depends strongly on the surface density of cross-bridges. In addition, the results provide an estimate of the restraining forces that anchor receptors within the plane of the membrane.

Cell Adhesion↗

Photochemically induced charge separation occurring in bacteriorhodopsin. Detection by time-resolved dielectric loss.

Time-resolved dielectric loss (TRDL) measurements are reported for the photochemical excitation of bacteriorhodopsin (bR) in solid films of Halobacterium halobium purple membranes. These measurements provide an independent confirmation for the existence of an important component of charge separation in these membranes after photochemical excitation. The separation of charge is detected by the absorption of microwave energy by the multilayer films of purple membranes in a microwave cavity during flash photolysis experiments. The TRDL method has the advantage of being sensitive to charge separation occurring in both oriented and unoriented films of purple membranes. One disadvantage is that the water content of the samples must be minimized, however, there is some absorbed water present in our electrodeposited solid film samples. To the best of our knowledge, TRDL measurements have not been reported previously for photochemical charge separation in biological membranes. It is significant that an early decay component of TRDL in the 20-microseconds time domain corresponds to the relaxation of the negative charge displacement photocurrent in oriented samples of purple membranes. In addition, a component of charge separation persists during the first several hundred microseconds of the bR photocycle.

Bacteriorhodopsins↗

Separation of submicron bioparticles by dielectrophoresis.

Submicron particles such as latex spheres and viruses can be manipulated and characterized using dielectrophoresis. By the use of appropriate microelectrode arrays, particles can be trapped or moved between regions of high or low electric fields. The magnitude and direction of the dielectrophoretic force on the particle depends on its dielectric properties, so that a heterogeneous mixture of particles can be separated to produce a more homogeneous population. In this paper the controlled separation of submicron bioparticles is demonstrated. With electrode arrays fabricated using direct write electron beam lithography, it is shown that different types of submicron latex spheres can be spatially separated. The separation occurs as a result of differences in magnitude and/or direction of the dielectrophoretic force on different populations of particles. These differences arise mainly because the surface properties of submicron particles dominate their dielectrophoretic behavior. It is also demonstrated that tobacco mosaic virus and herpes simplex virus can be manipulated and spatially separated in a microelectrode array.

Electric Conductivity↗

Neonatal maternal separation reduces hippocampal mossy fiber density in adult Long Evans rats.

Neonatal maternal separation of rat pups leads to a stable stress hyper-responsive phenotype characterized by increased basal levels of corticotropin releasing factor (CRF) mRNA in the hypothalamic and extra-hypothalamic nuclei, increased hypothalamic CRF release, and enhanced adrenocorticotrophin hormone (ACTH) and corticosterone (CORT) responses to psychological stressors. Stress and exposure to glucocorticoids either early in life or in adulthood have been associated with hippocampal atrophy and impairments in learning and memory. In this study, male Long Evans rat pups were exposed to daily 3-h (HMS180) or 15-min (HMS15) periods of maternal separation on postnatal days (PND) 2-14 or normal animal facility rearing. Maternal separation and subsequent reunion with the dam resulted in elevated plasma CORT levels versus HMS15 animals at PND7, a time when rat pups are normally hyporesponsive to stressors and show limited pituitary-adrenal responses. As adults, HMS180 rats exhibited elevated indices of anxiety, startle-induced pituitary-adrenal hyper-responsiveness, and slight, but significant impairment on acquisition in the Morris water maze task. In addition, HMS180 rats exhibited decreased mossy fiber density in the stratum oriens region of the hippocampus as measured by Timm's staining, but no change in volume of the dentate gyrus. These changes may be the result of neonatal exposure to elevated glucocorticoids and/or changes in other signaling systems in response to maternal separation. Overall the results suggest that repeated, daily, 3-h maternal separations during critical periods of hippocampal development can disrupt hippocampal cytoarchitecture in a stable manner. The resulting change in morphology may contribute to the subtle, but consistent learning deficit and overall stress hyper-responsive phenotype observed in these animals.

Adrenocorticotropic Hormone↗

Effects of maternal separation on behavioural sensitization produced by repeated cocaine administration in adulthood.

We examined whether early maternal separation influenced the susceptibility to behavioural sensitization produced by repeated intravenous (i.v.) injections of cocaine in adult female rats. For the first 21 days of life litters were separated from their mother for either 15 min (MS-15) or 180 min/day (MS-180). Control animals were subjected only to regular cage changes (animal facility reared; AFR). In adulthood, these three groups did not differ in their locomotor response to placement in a novel environment or to an acute i.v. injection of cocaine. After six additional daily injections of either saline or cocaine and following a 7-day drug-free interval, sensitization was assessed by giving all rats a challenge i.v. injection of cocaine. Rats exposed to either period of maternal separation (MS-15 or MS-180) showed significantly less robust sensitization than AFR rats. Therefore, early maternal separation decreased susceptibility to behavioural sensitization produced by cocaine in adulthood and the specific duration of maternal separation had no effect on this outcome.

Animals↗

Phase separation in the mixture of schizophyllan and poly(ethylene oxide) in aqueous solution driven by a specific interaction between the glucose side chain and poly(ethylene oxide).

We found that the mixture of schizophyllan and poly(ethylene oxide) in aqueous solution underwent phase separation at around 3-4 degrees C, and this temperature was independent of both polymer concentration and the difference in poly(ethylene oxide) molecular weight (Mw 6000 and 70,000). The phase-separation took place at the same temperature at which the optical rotation changed. Since the optical rotation change is ascribed to the difference in the nature of hydrogen bonding between the schizophyllan side chain and water, the phase separation is also considered to be due to an interaction between poly(ethylene oxide) and schizophyllan. The phase-separation temperature increased on changing H2O to D2O in accordance with a change in the optical rotation, confirming the specific interaction essential for the phase separation.

Chemical Phenomena↗

Separation of six uremic middle molecular compounds by high performance liquid chromatography and analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

BACKGROUND: Since the postulation of uremic middle molecule (UMM) hypothesis made by Babb et al. [Trans-Am Soc Artif Intern Organs 18 (1972) 98], there has been great interest in the separation and identification of the role of UMM. However, few of the compounds isolated from UMM fractions were demonstrated to play an important role in humans. Thus, the separation and identification of the real UMM is essential for UMM research. METHODS: Urine and serum samples from uremic patients and healthy subjects were separated by gel permeation chromatography. Two presumed UMM fractions, A and B, were obtained from uremic sera and urine, normal urine, but not normal sera. Fraction A was further isolated by anion exchange chromatography and a series of sub-peaks were obtained. The sub-fraction A-3 obtained in the second step was desalted on a Sephadex G-15 column, and characterized by IR, UV and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Further separation of sub-fraction A-3 was performed by high performance liquid chromatography (HPLC). RESULTS: By gel permeation chromatography, two UMM peaks (A and B) were detected at 206 nm in normal urine, uremic sera, but they were barely noticed in the profile of normal sera. In contrast, the absorption at 206 nm of fractions A and B from uremic serum and urine were smaller than that of fractions A and B from normal urine. Fractions A from different origins were resolved into eight to nine sub-peaks at 230 nm by anion exchange chromatography. One of these sub-peaks, A-3, was detected in uremic serum and normal urine, but is undetectable in uremic urine. After desalting, sub-fraction A-3 was separated into two parts designated as A-3-I and A-3-II. MALDI-TOF-MS revealed that fraction A-3-I and A-3-II from two origins were identical, respectively-fraction A-3-I contained three components with MW 839.69, 1007.94 and 2015.16 and fraction A-3-II consisted of another three components with MW 873.69, 1106.67 and 1680.28. Six middle molecular compounds in sub-fraction A-3 were thoroughly resolved by HPLC. CONCLUSION: Our results demonstrated that the UMM sub-fraction A-3 contains the real UMM in the MW range of 800-2015 Da. By multi-step chromatographic isolation, six real middle molecular compounds were purified and characterized with MALDI-TOF-MS. It is likely that three of these UMM compounds are important, as they readily accumulated in sera of uremic patients, but are normally excreted in healthy subjects.

Adult↗