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The presence or absence of light during flotation restricted environmental stimulation: Effects on plasma cortisol,blood pressure,and mood 总被引:1,自引:0,他引:1
John W. Turner Jr. Thomas Fine Gina Ewy Peter Sershon Thomas Freundlich 《Applied psychophysiology and biofeedback》1989,14(4):291-300
This study examined the effect of light on relaxation associated with flotation restricted environmental stimulation therapy (REST), as measured by plasma cortisol, mean arterial pressure, and psychometric parameters. Twenty-one subjects were paired by baseline cortisol levels into two groups: one experiencing flotation REST in the presence of light (REST-L) and one experiencing flotation REST in the absence of light (REST-D). Subjects were 15 male and 6 female students aged 22–28 in normal health who had not experienced REST. Repeated flotation REST (8 sessions) either with light or without light was associated with a decrease in plasma cortisol and a decrease in mean arterial pressure, with no differences in effectiveness between groups. The psychometric assessment of mood, using the POMS scale, before and after sessions 1 and 8 revealed mood state improvement in both REST-L and REST-D groups. These data suggest that the presence of light did not compromise the flotation REST experience, as evidenced by the lack of difference between REST-L and REST-D groups. 相似文献
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Detergent soluble extracts of differentiated regions of the Porphyra perforata J. Ag. thallus (holdfast, rhizoidal, vegetative and reproductive cells) were fractionated on sodium dodecyl sulfate polyacrylamide gels. Glycoproteins were identified by their lectin affinity. Extracts from all areas of the thallus contained glycoproteins, but the staining patterns were different for each region with each of the lectins tested: concanavalin A, Ulex europeaus agglutinin, Ricinus communis agglutinin, soybean agglutinin and peanut agglutinin. These data indicate that the morphologically distinct regions of the thallus also differ biochemically. Analysis of the lectin blots revealed the presence of tissue-specific glycoproteins in the five thallus areas. Such unique glycoproteins could be used as markers of differentiation in this species. 相似文献
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Reconstitution of the rat liver vasopressin receptor coupled to guanine nucleotide-binding proteins 总被引:2,自引:0,他引:2
B F Dickey J B Fishman R E Fine J Navarro 《The Journal of biological chemistry》1987,262(18):8738-8742
The V1 vasopressin receptor has been solubilized from rat liver membranes with the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammoniol]-1-propanesulfonate (CHAPS) and reconstituted into phospholipid vesicles. There is essentially complete solubilization of the receptor by 3% CHAPS at a protein concentration of 15 mg/ml. Reconstitution into soybean phospholipid vesicles is readily achieved either by gel filtration chromatography or by membrane dialysis. The binding of [3H]vasopressin to proteoliposomes is specific, saturable, reversible, and magnesium-dependent. In contrast, the detergent-soluble vasopressin receptor does not display specific binding. The apparent affinity of the reconstituted receptor for [3H]vasopressin is approximately 4-fold lower than that of the receptor in native membranes. In addition, the binding of [3H]vasopressin to reconstituted vesicles is not sensitive to 100 microM guanosine 5'-O-thiotriphosphate (GTP gamma S) as it is in native membranes. However, the apparent affinity of the reconstituted receptor for ligand approximates that of native membranes when membranes are prebound with vasopressin prior to solubilization and reconstitution into vesicles. Furthermore, vesicles reconstituted from membranes prebound with vasopressin show GTP gamma S sensitivity of [3H] vasopressin binding. This finding strongly suggests that vasopressin stabilizes a receptor-G-protein complex during solubilization. The rat liver vasopressin receptor is a glycoprotein, as shown by its specific binding to the lectin "wheat germ agglutinin." The vasopressin receptor can be reconstituted from the N-acetylglucosamine-eluted peak of a wheat germ agglutinin-Sepharose column, and [3H] vasopressin binding activity is purified 5-6-fold from membranes by this chromatographic procedure. The functionality of the partially purified receptor is indicated by its ability to bind ligand with high affinity and by its ability to functionally interact with a G-protein when vasopressin is bound prior to solubilization. 相似文献
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Melanoma growth stimulatory activity (MGSA) was originally described as an endogenous growth factor for human melanoma cells. To test the hypothesis that an MGSA autocrine loop is responsible for the partial freedom from growth control observed in nevocytes and melanoma cells, MGSA growth response and MGSA mRNA/protein levels were examined in these cells compared with normal melanocytes. As a single agent, or in combination with other factors, MGSA stimulated the growth of normal human epidermal melanocytes as well as other growth promoters for melanocytes. Nevocytes were not as responsive to exogenous MGSA as melanocytes. MGSA mRNA was minimal or not detected in cultured normal melanocytes, although the protein was present when the cells were cultured in the presence of serum/growth factors and absent when serum/growth factors were omitted. In contrast, MGSA mRNA was constitutively expressed in the absence of exogenous growth factors in cultures established from benign intradermal and dysplastic nevi and melanoma lesions in different stages of tumor progression. Nevus cultures contained immunoreactive MGSA protein in the presence of serum but were negative or only faintly positive in the absence of serum. Melanoma cell lines were positive for MGSA protein in both the presence and the absence of serum. Thus, continued expression of both MGSA mRNA and MGSA protein in the absence of exogenous hormones or serum factors may correlate with partial freedom from growth control exhibited by malignant melanocytes. 相似文献
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A Keyvanfar D Rochu J M Fine 《Comparative biochemistry and physiology. B, Comparative biochemistry》1988,90(2):393-396
1. Soluble caviar (oocyte) proteins of four sturgeon species from the Caspian sea, Acipenser stellatus (Sevrouga), Acipenser guldenstadti (Ossietre), Acipenser nudiventris (Chipe) and Huso huso (Belouga) were studied by isoelectric focusing. 2. Isoelectric focusing patterns of these proteins differ from one species to another and allow the identification of the specific origin of caviar. 3. Moreover, this technique allowed the discrimination of a subspecies, Acipenser guldenstadti persicus from the species. 4. This biochemical characterization of caviar proteins allowing identification of sturgeon species producing caviar could be added to data used in fraud tests. 相似文献