Different Degrees Of Stimulation Research Articles

Study of the relationship between acupuncture dose and effect

Study of the relationship between acupuncture dose and effect

Characterization of the hypothalamo–pituitary–gonadal axis in low and high egg producing turkey hens

Variation in egg production exists in commercial turkey hens, with low egg producing hens (LEPH) costing more per egg produced than high egg producing hens (HEPH). Egg production correlates with ovulation frequency, which is governed by the hypothalamic–pituitary–gonadal (HPG) axis. Ovulation is stimulated by a preovulatory surge (PS) of progesterone and luteinizing hormone, triggered by gonadotropin releasing hormone release and inhibited by gonadotropin inhibiting hormone. Differences between LEPH and HEPH were characterized by determining HPG axis plasma hormone profiles and mRNA levels for key genes, both outside and inside of the PS (n = 3 per group). Data were analyzed with a 2-way ANOVA using the mixed models procedure of SAS. In the HPG axis, plasma progesterone levels were not affected by egg production level but were elevated during the PS. In contrast, plasma estradiol levels were higher in HEPH than in LEPH but were not associated with the PS. LEPH exhibited decreased gene expression associated with ovulation stimulation and increased gene expression associated with ovulation inhibition in the hypothalamus and pituitary. In ovarian follicle cells, LEPH displayed decreased gene expression associated with progesterone, androgen, and estradiol production in the F1 follicle granulosa cells, F5 theca interna cells, and small white follicle cells, respectively. Different degrees of stimulation and inhibition within all tissues of the HPG axis were noted between LEPH and HEPH turkey hens, with HEPH showing higher expression of genes related to ovulation and steroidogenesis.

The use of bioluminescence stimulant on the immobilized strain, P. putida mt-2 KG1206, with toluene analog inducers and environmental samples

This study was conducted to investigate the applicability of the stimulant conditions for the bioluminescence activity of a recombinant strain of Pseudomonas putida, mt-2 KG1206, when immobilized using alginate polymer. The bioluminescence activity of the immobilized strain was generally approximately three to five times lower than the subcultured strain, and the activity was observed to slowly decrease. These facts may have been caused by several factors, such as the low biomass and the time required for diffusion into the entrapped biomass. Although different inducers produced different degrees of stimulation, immobilized bacteria modified with KNO(3) consistently produced more bioluminescence than those treated with sodium lactate, regardless of the inducer chemical tested. Cells treated with KNO(3) exhibited 2.8 times greater bioluminescence than that of the control activity. This condition also stimulated the bioluminescence activities of the immobilized bacteria exposed to contaminated groundwater samples. Based on these results, the immobilized KG1206 presented in this research can be used as a portable assay for the purpose of preliminary on-site monitoring of specific inducer contaminants, with subsequent off-site instrumental analysis, suggesting the potential of this immobilized cell for preliminary application in a field-ready bioassay.

473 PUBLICATION High-dose chemotherapy and autologous peripheral blood stem cell transplantation in metastatic breast cancer. updated results of a single center

Multidrug-resistant (MDR) tumor cells reduce the toxicity of antineoplastic drugs by an energy-dependent active efflux mechanism mediated by the MDR1 gene product, the P-glycoprotein (Pgp). Pgp expressed in cultured Sf9 insect cells has been shown to exhibit a high capacity ATPase activity in the presence of a variety of drugs known to be transported by the Pgp (Sarkadi et al., J Biol Chem267: 4854–4858, 1992). The strict dependence of the Pgp ATPase activity on the presence of transport substrates indicates that the drug-stimulated ATPase activity is a direct reflection of the drug transport function of the Pgp. In the present study, this system has been utilized to investigate the possibility that antiestrogens and steroid hormones are transported by the Pgp. Antiestrogens such as tamoxifen, metabolites of tamoxifen (4-hydroxytamoxifen and N-desmethyltamoxifen), droloxifen, and toremifene stimulated the Pgp ATPase activity, and the maximum stimulation obtained with these agents equalled the maximal stimulation obtained by the best known MDR chemosensitizer, verapamil. Clomifene, nafoxidine and diethylstilbestrol also stimulated the Pgp ATPase activity, with maximal activations 75, 60 and 45% of the verapamil stimulation, respectively. Different degrees of stimulation of the Pgp ATPase activity were also obtained in the presence of steroid hormones such as progesterone, ;β-estradiol, hydrocortisone, and corticosterone. Among these, progesterone is a potent inducer of the Pgp ATPase activity; at 50 μM, this hormone stimulated the Pgp ATPase activity as effectively as verapamil. These results suggest that the antiestrogens and steroid hormones that are known to reverse the multidrug-resistant phenotype do so by directly interacting with Pgp, thus interfering with its anticancer drug-extruding activity.

Reliability of nurses' neurological assessments in the cardiothoracic surgical intensive care unit

Alterations in mental status are common among patients in the cardiothoracic surgical intensive care unit. Changes in mental status can be caused by metabolic factors, medications, or brain injury. In this setting, reliable, serial neurological evaluations are critical for assessing the effectiveness of treatment and the need for additional studies. To estimate the reliability of the Rancho Los Amigos Cognitive Scale and the newly developed Neurologic Intensive Care Evaluation as measures of cognitive function in the cardiothoracic surgical intensive care unit. Nurses used 1 of the 2 scales as part of routine neurological assessments of patients in the cardiothoracic surgical intensive care unit. For each test, scores of different observers were correlated and a reliability estimate formed. Interrater reliability was high for both evaluations (Rancho scale, 0.91; Neurologic Intensive Care Evaluation, 0.94). Correlations between the scores of different pairs of observers were also high (mean rho values, 0.84 for the Rancho scale and 0.77 for the Neurologic Intensive Care Evaluation). Both scales are reliable indicators of the neurological state of patients in the cardiothoracic surgical intensive care unit. These scales measure different, although limited, aspects of cognitive function. Each test was simple to administer and did not take more time than the standard nursing neurological examination. Most of the variability in scoring was related to the different degrees of stimulation used by examiners when assessing patients, not to differences in the interpretation of patients' responses.

Antiestrogens and steroid hormones: Substrates of the human P-glycoprotein

Multidrug-resistant (MDR) tumor cells reduce the toxicity of antineoplastic drugs by an energy-dependent active efflux mechanism mediated by the MDR1 gene product, the P-glycoprotein (Pgp). Pgp expressed in cultured Sf9 insect cells has been shown to exhibit a high capacity ATPase activity in the presence of a variety of drugs known to be transported by the Pgp (Sarkadi et al., J Biol Chem 267: 4854–4858, 1992). The strict dependence of the Pgp ATPase activity on the presence of transport substrates indicates that the drug-stimulated ATPase activity is a direct reflection of the drug transport function of the Pgp. In the present study, this system has been utilized to investigate the possibility that antiestrogens and steroid hormones are transported by the Pgp. Antiestrogens such as tamoxifen, metabolites of tamoxifen (4-hydroxytamoxifen and N-desmethyltamoxifen), droloxifen, and toremifene stimulated the Pgp ATPase activity, and the maximum stimulation obtained with these agents equalled the maximal stimulation obtained by the best known MDR chemosensitizer, verapamil. Clomifene, nafoxidine and diethylstilbestrol also stimulated the Pgp ATPase activity, with maximal activations 75, 60 and 45% of the verapamil stimulation, respectively. Different degrees of stimulation of the Pgp ATPase activity were also obtained in the presence of steroid hormones such as progesterone, ;β-estradiol, hydrocortisone, and corticosterone. Among these, progesterone is a potent inducer of the Pgp ATPase activity; at 50 μM, this hormone stimulated the Pgp ATPase activity as effectively as verapamil. These results suggest that the antiestrogens and steroid hormones that are known to reverse the multidrug-resistant phenotype do so by directly interacting with Pgp, thus interfering with its anticancer drug-extruding activity.

Stimulation of the growth and differentiation of axons and dendrites of the spinal neurons in tissue culture

Regeneration of axons and dendrites after damage to the spinal cord results in partial restoration of the nervous connections and functional activity. Some authorities have used substances of different nature which actively affecting the processes of differentiation of the nervous system in order to stimulate the restoration processes. Experiments in transplanting embryonic spinal cord to the damaged region of the spinal cord of mature animals have also been performed. The recovery of functional activity was not observed in the majority of cases, although active growth of axons was noted [5,6,13]. Now, in addition to nerve growth factor, the classical agent stimulating neuronal differentiation in the spinal and sympathetic ganglia, a group of substances affecting the growth of axons and their collaterales has been studied. Serotonm [15], dalargin [7], fusaric acid [10], insulin [14], cytosine arabinoside [12], substance P [9], and GABA [11] all possess different degrees of stimulation. The present investigation was undertaken to study the effect of blood serum from human umbilical cord (BSHUC), of dalargin, and of supernatant of somatic muscle tissue on the growth of axons and dendrites of spinal cord motoneurons.

Differential effects of transforming growth factor-beta on the synthesis of extracellular matrix proteins by normal fetal rat calvarial bone cell populations.

To determine the effects of transforming growth factor-beta (TGF-beta) on the different cell types that exist in bone, cell populations (I-IV), progressively enriched in osteoblastic cells relative to fibroblastic cells, were prepared from fetal rat calvaria using timed collagenase digestions. TGF-beta did not induce anchorage-independent growth of these cells, nor was anchorage-dependent growth stimulated in most populations studied, despite a two- to threefold increase in the synthesis of cellular proteins. In all populations the synthesis of secreted proteins increased 2-3.5-fold. In particular, collagen, fibronectin, and plasminogen activator inhibitor synthesis was stimulated. However, different degrees of stimulation of individual proteins were observed both within and between cell populations. A marked preferential stimulation of plasminogen activator inhibitor was observed in each population, together with a slight preferential stimulation of collagen; the effect on collagen expression being directed primarily at type I collagen. In contrast, the synthesis of SPARC (secreted protein acidic rich in cysteine/osteonectin was stimulated approximately two-fold by TGF-beta, but only in fibroblastic populations. Collectively, these results demonstrate that TGF-beta stimulates matrix production by bone cells and, through differential effects on individual matrix components, may also influence the nature of the matrix formed by different bone cell populations. In the presence of TGF-beta, osteoblastic cells lost their polygonal morphology and alkaline phosphatase activity was decreased, reflecting a suppression of osteoblastic features. The differential effects of TGF-beta on bone cell populations are likely to be important in bone remodeling and fracture repair.

Involvement of FMN and phenobarbital cytochrome P-450 in stimulating a one-electron reductive denitrosation of 1-(2-chloroethyl)-3-(cyclohexyl)-1-nitrosourea catalyzed by NADPH-cytochrome P-450 reductase.

Purified hepatic NADPH-cytochrome P-450 reductase, which was reconstituted with dilauroylphosphatidylcholine, catalyzed a one-electron reductive denitrosation of 1-(2-[14C]-chloroethyl)-3-(cyclohexyl)-1-nitrosourea ([14C]CCNU) to give 1-(2-[14C]-chloroethyl)-3-(cyclohexyl)urea at the expense of NADPH. Ambient oxygen or anoxic conditions did not alter the rates of [14C]CCNU denitrosation catalyzed by NADPH-cytochrome P-450 reductase with NADPH. Electron equivalents for reduction could be supplied by NADPH or sodium dithionite. However, the turnover number with NADPH was slightly greater than with sodium dithionite. Enzymatic denitrosation with sodium dithionite or NADPH was observed in anaerobic incubation mixtures which contained NADPH-cytochrome P-450 reductase with or without cytochrome P-450 purified from livers of phenobarbital (PB)-treated rats; PB cytochrome P-450 alone did not support catalysis. PB cytochrome P-450 stimulated reductase activity at molar concentrations approximately equal to or less than NADPH-cytochrome P-450 reductase concentration, but PB cytochrome P-450 concentrations greater than NADPH-cytochrome P-450 reductase inhibited catalytic denitrosation. Cytochrome c, FMN, and riboflavin demonstrated different degrees of stimulation of NADPH-cytochrome P-450 reductase-dependent denitrosation. Of the flavins tested, FMN demonstrated greater stimulation than riboflavin and FAD had no observable effect. A 3-fold stimulation by FMN was not observed in the absence of NADPH-cytochrome P-450 reductase. These studies provided evidence which establish NADPH-cytochrome P-450 reductase rather than PB cytochrome P-450 as the enzyme in the hepatic endoplasmic reticulum responsible for CCNU reductive metabolism.

The role of chemotactile stimuli in the oviposition preferences of Colias butterflies.

The legume foodplants of Colias butterflies possess specific chemical components which stimulate oviposition in females of the genus. Different legumes provide different degrees of stimulation, as demonstrated by close correlation between field observations and laboratory experiments with a new behavioral assay. Several generalizations emerge from this study. 1) Chemical preferences for various foodplants are under genetic control in C. meadii, and are at least partly independent of an individual's previous exposure to different legumes. 2) In some cases, chemical cues alone do not allow females to discriminate between species. Long-range search cues may be used to enhance discrimination in such instances. 3) Lupinus, a legume which is not usually utilized by Colias, stimulates oviposition in the laboratory, indicating its chemical affinity with other Leguminosae. The behavioral assay described should prove useful for the future identification of specific oviposition stimulants and deterrents. It is stressed, however, that chemotactile cues are involved only in the final step of oviposition, and that understanding foodplant choice in nature will require in-depth investigation into the mechanics of individual search processes.

Stimulation of Plant Growth by Humic Substances

AbstractHumic substances prepared by different techniques of extraction and from different sources of organic materials were tested for their effects on growth of corn seedlings and algae. Stimulating effects were confirmed with optimum concentrations about 5 ppm C as Na‐humate for corn and 60 ppm for algae. With corn, the increase was 30 to 50% in nutrient solution or low organic matter soil; with algae, about 100%. Variation of effects among humic acids derived from different organic materials was not great.The concentrations of elements in corn seedlings did not show any correlation with yield or humic acid level except for P and Fe. Phosphorus concentration was increased with increasing levels of humic acid regardless of the yield response. Higher Fe concentration in the plant tops and lower in roots was observed in the treatments with humic acid.The application of humic acid to a soil low in organic matter or to nutrient solution gave the greatest growth response. Application to a high organic matter soil gave little growth response, or even a slightly negative response, indicating that the natural soil, without extraction, supplied optimum amount of humic substances to the plants. It is suggested that a test be developed to predict whether a given soil can furnish an optimum level of humic substances.Different humic substances showed different degrees of stimulation of algal growth, with the most stimulation from a mixture of humic and fulvic acids. Humic substances in paddy soils may affect the growth of beneficial algae and of the rice (Oryza sativa L.) itself. As pollutants, humic substances may stimulate undesirable algal growth in bodies of water.

Multiple molecular forms of phosphoprotein phosphatase: III. Phosphorylase phosphatase and phosphohistone phosphatase of rabbit liver

1. 1.|Phosphoprotein phosphatase (phosphoprotein phosphohydrolase EC 3.1.3.16) in the soluble fraction of rabbit liver which catalyzes the dephosphorylation of muscle phosphorylase a and phosphohistone ( P-histone) was resolved into three active fractions by NaCl gradient elution from a DEAE-cellulose column (Fraction I, II and III in order to elution). They have different relative reaction rates for the two substrates and different degrees of stimulation by Mn 2+. Apparent K m values of Fraction I, II and III were 15, 20 and 16 μM for phosphorylase a, and 6.9, 5.3 and 4.4 μM for P-histone, respectively (with Mn 2+ in the assay mixture). 2. 2.|On sucrose density gradient centrifugation Fraction I and II were revealed to contain a major peak (7.0 S and 7.8 S, respectively) and a minor peak (4.0 S) of activity, while Fraction III contained only one peak (5.8 S). Freezing and thawing in the presence of 0.2 M mercaptoethanol dissociated all three fractions into subunits of similar molecular size (3.4 S), with concomitant enhancement of phosphorylase phosphatase activity. The K m values all became essentially the same (20 μM for phosphorylase a and 16 μM for P-histone). 3. 3.|The phosphorylase phosphatase and P-histone phosphatase activities could not be separated with any of the procedures described. Competition between the two phosphoprotein substrates was observed with some of the fractions.

Action des hormones androgenes sur l'epididyme d'un reptile lacertilien, Lacerta vivipara jacquin. Effets de la testosterone et de ses principaux mètabolites en culture organotypique

The lizard epididymis is controlled by the testis, as is demonstrated by castration. It selectively retains testosterone and is capable of converting this hormone into 5α-dihydrotestosterone and 5α-androstanediols. Furthermore, it shows marked modifications of structure, particularly of the epithelium, during the annual cycle and is characterized by a copious secretion when active. In organotypic culture of regressed cells from castrated animals we have obtained secretory cells of normal size after treatment with a variety of androgens. Different degrees of stimulation were observed: 5α-DHT and 3β-androstanediol are more potent than 3α-androstanediol and the latter is more potent than testosterone. Electron-microscopic examination of treated tissue shows that 5αDHT produces an increase in nuclear and nucleolar size and conspicuously stimulates the production of rough endoplasmic reticulum. It is suggested that this organ might be used as a model to study the mechanism of androgen action.

The oxygen consumption of mayfly (Ephemeroptera) and stonefly (Plecoptera) larvae at different oxygen concentration

1. The aim of this investigation was to elucidate how four acquatic insect larvae, from different habitats and having different respiratory organs or types of respiratory regulation, react to a lowered oxygen concentration, and how their oxygen consumption is affected. The species investigated were the stoneflies Taeniopteryx nebulosa, Diura nanseni and Nemoura cincerea and the mayfly Cloeon dipterum. 2. The measurements were performed in a respiratory apparatus of open, flowing-water type. Its design is shown in Fig. 1. Water of known oxygen concentration was allowed to flow past the experimental larvae. The oxygen consumption of the larvae was calculated from the lowering of the oxygen concentration in which ensued. 3. The water used in the experiments was standardized, so that the electrode had the necessary stability (conductivity 470 micromhos/cm). The calcium ion was excluded in order to prevent the precipitation of CaCO3 in the electrode capillary. 4. A large variation in the values of oxygen consumption was found as seen in Fig. 2–5. The reason for that is a corresponding variation in the motor activity of the experimental animals. 5. The physiological reasons for the general form of the curves A and C in Fig. 2–5 are discussed. The curves A and C represent oxygen consumption of the larvae at different degrees of stimulation, entailing different levels of motor activity. Curve A represents intentinally activated animals, curve C non-activated, motionless animals. The curves A and C are boundary curves corresponding to a sort of scope for activity of the animals. Over this scope area a series of curves of the same form could in principal be construed, representing different degrees of stimulation. 6. Within a certain oxygen concentration interval a motor activation was observed caused by a reduced oxygen concentration. The result of that activation can be seen in Fig. 2–5 as a zone with no or very few oxygen consumption values between curve C and D. The more easily activated the species is, the broader the zone will be. Cloen has the most narrow zone and was observed to be less activated than the other species. 7. Small larvae of Cloen (2–4 mm and 42–6 mm) and Nemoura (2–4 mm) showed clearly a greater ability to take up oxygen at low oxygen concentrations than full-grown larvae (see Fig. 8 and 9). 8. The critical point on the curve representing mean oxygen consumption as a function of oxygen concentrations was found to be at 2–5 mg O2/1 for Taeniopteryx and Diura, at 2.2–2.5 mg O2/1 for Cloeon, and at about 2–7 mg O2/1 for Nemoura. The values refer to 8°. Cloeon is the species which is exposed to the greatest variations in oxygen concentration in its natural environment. 9. No influence on the oxygen consumption of starvation for 4 to 5 days was found. No difference between the oxygen consumption values obtained in the presence or in the absence of calcium ions could be observed during the experiments (Fig. 10, 11). 10. The basic picture obtained in this investigation is a set of oxygen consumption values scattered between a curve connecting highest values obtained and a curve of the standard metabolism together with a zone in which the larvae are activated by reduced oxygen concentrations. This picture is presumed to be general in aquatic animals with a well developed motor activity.

Inability of insulin to activate liver glycogen transferase D phosphatase in the diabetic pancreatectomized dog

1. 1. Administered insulin promotes an increase in the I form of liver glycogen transferase (UDPG: α-I,4-glucos α-4-glucosyltransferase (EC 2.4.I.II) less effectively when infused into pancreatectomized dogs made “diabetic”, by deprivation of maintenance insulin for 2–4 days, than into such dogs “controlled” by daily insulin. Since an increase in transferase I is probably promoted by transferase D phosphatase, a decrease in the activity of this enzyme was sought as a possible explanation for this kind of insulin resistance. 2. 2. It was found that insulin (3.2 units/kg per h)-with-glucose (2.5 g/kg per h) infused into “controlled” dogs promoted a several-fold increase in phosphatase activity within 5–15 min. Glucagon added to the insulin-with-glucose infusion brought phosphatase activity back to control levels or below, within 6 min. 3. 3. This rapid activation-inactivation of phosphatase by hormones suggests the existence of two activities of phosphatase which are interconverted enzymatically and exhibit different degrees of stimulation by Mg 2+. 4. 4. In “diabetic” dogs no change in phosphatase activity was brought about by a similar infusion of insulin-with-glucose for 30–120 min. 5. 5. It is suggested that in insulin deficiency the activating factor for liver transferase D phosphatase is either lacking or ineffective.

QUANTITATIVE ASSAY OF ANTIGENIC DISPARITY AT HL-A—THE MAJOR HISTOCOMPATIBILITY LOCUS IN MAN

We have extended the method of one-way stimulation in mixed leukocyte culture tests as previously described to quantitate different degrees of stimulation. To demonstrate that the amount of stimulation is immunogenetically meaningful, siblings and parents in families in whom genotyping on the basis of leukocyte antigen data was possible were tested. The prediction that cells of siblings differing from the responding sibling by both alleles at HL-A, stimulate more than do cells of siblings differing by only one allele, was realized in every case. One exception, with cells of a parent, is discussed. It is stressed that the differences measured here are probably fairly strong ones in the majority of cases, and that lesser differences cannot yet be detected reproducibly.