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1.
Dose response uterotrophic and antiuterotrophic activity of antiestrogens was examined in immature rats, immature mice and adult ovariectomized mice. LY117018 was the most active antagonist and the least estrogenic, while tamoxifen induced the greatest uterine growth and the weakest antagonism. The reported estrogenic activity of tamoxifen in mice (1) was found to be related to maturity. All compounds caused uterotrophic changes in immature mice similar to those observed in immature rats. However, in adult mice tamoxifen was devoid of antagonism, and trioxifene was active only at a very high dose as both were extremely estrogenic in this model. LY117018 activity in adult mice was comparable to that observed in immature rats and mice. Results depict significant agonist and antagonist advantages of LY117018 over tamoxifen and trioxifene. 相似文献
2.
The present study was designed to investigate the dose-response of clomiphene on several estrogenic responses in the immature rat uterus and to compare it to available data on estradiol-17 beta. A dissociation was demonstrated among the different estrogenic responses induced by clomiphene. Very high doses of clomiphene were needed to induce the 6-h uterine eosinophilia and deep endometrial edema, and maximal response levels were not reached at any dose studied. On the contrary, many genomic responses were induced with much lower doses of clomiphene, and maximal response levels were reached with at least the two highest doses of clomiphene. This dissociation is in agreement with the existence of separate groups of responses that are mediated by multiple and independent mechanisms of estrogen action involving different kind of receptors. Luminal epithelial, glandular epithelial, and myometrial hypertrophies were also found to differ with regard to the dose needed to induce this response in each cell type. The dissociation between genomic responses of the different uterine cell types supports the hypothesis of different estrogen receptors for each kind of cell. Clomiphene induces mitoses in the different cell types, but the proportion of mitoses in the cell types was different from that described for estradiol. It is suggested that these differences are also due to differences between receptors involved in cell proliferation. 相似文献
3.
Colette Briançon Sylvain Halpern Josette Jeusset Philippe Fragu 《Biological trace element research》1992,32(1-3):267-273
Analytical ion microscopy (AIM) was used to determine alterations in the thyroid follicular lumen127I stores of Wistar rats injected with different doses of129I (low specific activity radionuclide). Animals fed a normal iodine diet (10 μg127I/d) were divided into four groups: control group and three treated groups injected ip 24 h before sacrifice with129I at doses of 10 μg (group 1), 30 μg (group 2), and 8500 μg (group 3). AIM was performed on thyroid semithin sections. The
mean129I concentration increased with the dose injected from group 1 (0.44±0.03 μg/mg, mean ± SEM) to group 2 (2.05±0.14 μg/mg) and
decreased in group 3 (0.57±0.08 μg/mg). When compared to control group (4.14±0.17 μg/mg), the mean127I concentration was not changed in group 1 (4.52±0.07 μg/mg), but altered in the other groups: It was significantly increased
(7.14±0.41 μg/mg) in group 2 and slightly decreased (3.11±0.26 μg/mg) in group 3. These results underline the interest of
AIM in the study of the effects of various doses of iodide on the thyroid autoregulation by iodide, a trace element actively
trapped by this gland. 相似文献
4.
Vogt AM Elsässer A Pott-Beckert A Ackermann C Vetter SY Yildiz M Schoels W Fell DA Katus HA Kübler W 《Molecular and cellular biochemistry》2005,278(1-2):223-232
For both, cardioplegia (CP) and ischemic preconditioning (IP), increased ischemic tolerance with reduction in infarct size
is well documented. These cardioprotective effects are related to a limitation of high energy phosphate (HEP) depletion. As
CP and IP have to be assumed to act by different mechanisms, their effects on myocardial HEP metabolism cannot be assumed
to be identical. Therefore, a systematic analysis of myocardial HEP metabolism for both procedures and their combination was
performed, addressing the question whether there are different effects on myocardial HEP metabolism by IP and CP. In this
study, metabolic control analysis was used to analyze the regulation of HEP metabolism. In open chest pigs subjected to 45
min LAD occlusion (index ischemia), CP and IP preserved myocardial ATP (control (C) 0.14 ± 0.05 μmol/g wwt; CP: 0.95 ± 0.14,
IP: 0.61 ± 0.12; p<0.05 C vs. CP and IP) and reduced myocardial necrosis (infarct size IA/RA: C: 90.0 ± 3.0%; CP: 0.0 ± 0.0% but patchy necroses;
IP: 5.05 ± 2.1%; p<0.05 C vs. CP and IP). The effects on HEP metabolism, however, were different: CP acted predominantly by slowing down the
breakdown of phosphocreatine (PCr) during early phases of ischemia (C: ΔPCr 0–2 min: 5.24 ± 0.32 μmol/g wwt; CP: ΔPCr 0–2
min: 3.38 ± 0.23 μmol/g wwt, p<0.05 vs. C), leaving ATP breakdown during later stages unaffected (C: ΔATP 5–45 min: 1.77 ± 0.11 μmol/g wwt CP: ΔATP 5–45
min: 1.59 ± 0.28 μmol/g wwt, n.s. vs. C). In contrast to CP, in IP PCr breakdown was even increased (IP: ΔPCr 0–2 min: 7.06
± 0.34 μmol/g wwt, p<0.05 vs. C), but ATP depletion greatly attenuated (IP: ΔATP 5–45 min: 0.48 ± 0.10 μmol/g wwt, p<0.05 vs. C and CP). Combining IP and CP yielded an additive effect with slowing down the breakdown of both PCr (IP+CP: ΔPCr
0–2 min: 5.09± 0.35 μmol/g wwt, p<0.05 vs. C and IP) and ATP (IP+CP: ΔATP 5–45 min: 0.56 ± 0.48 μmol/g wwt, p<0.05 vs. C and CP), resulting in a higher ATP content at the end of index ischemia (1.86 ± 0.46 μmol/g wwt, p<0.05 vs. C, CP and IP). Compared to IP, combining IP+CP achieved also a further reduction in infarct size (IA/RA: 0.0 ± 0.0%,
p<0.05 vs IP) and—compared to CP—a disappearance of the patchy necroses. {The concept of major differences in myocardial HEP
metabolism during CP and IP is further supported at a molecular level by metabolic control analysis. CP but not IP slowed
down the CK reaction velocity at high PCr levels. In contrast to CP exerting a continuous decline in vATPase for any given ATP level, in IP myocardium ATPase reaction velocity was even increased at higher ATP contents, whereas
a marked decrease in ATPase reaction velocity was found if ATP levels decreased. The equilibrium of the CK-reaction remained
unchanged following CP, whereas IP induced a changing CK equilibrium, which was the more shifted towards PCr the more myocardial
HEP content decreased. The data demonstrate different effects of CP and IP on myocardial HEP metabolism, i.e. PCr and ATP
breakdown as well as the apparent equilibrium of the creatine kinase (CK)-reaction. For these reasons the combination of the
two protective interventions has an additive effect. (Mol Cell Biochem 278: 222–232, 2005) 相似文献
5.
Kłapcińska B Poprzecki S Danch A Sobczak A Kempa K 《Biological trace element research》2005,108(1-3):1-15
The selenium status and the relationship of whole-blood selenium and plasma homocysteine are reported for healthy human subjects
living in Upper Silesia. A total of 1063 individuals (627 male and 436 female) examined for whole-blood selenium were subdivided
into six groups according to age; the youngest included adolescents (n=143) aged 10–15 yr, and the oldest were centenarians (n=132). The mean Se content was relatively low (62.5±18.4 μg/L), and it tended to be higher in men (65.9±17.2 μg/L) than in
women (57.5±18.9 μg/L). Selenium levels appeared to be age dependent, as the highest values were observed in young and middle-age
adults (21–40 yr), whereas they were significantly lower in adolescents and in the elderly. In more than 40% of apparently
healthy adults (aged 21–69 yr), the Se concentration was within the range 60–80 μg/L (i.e., below the lower limit of the nutritional
adequacy range [80 μg/L]). A significant inverse correlation between whole-blood selenium and plasma total homocysteine was
detected in a smaller population sample of middle-aged and elderly persons (n=204). 相似文献
6.
Akula Ramakrishna Parvatam Giridhar Kadimi Udaya Sankar Gokare Aswathanarayana Ravishankar 《Acta Physiologiae Plantarum》2012,34(1):393-396
Endogenous indoleamine profiles in various ex vitro and in vitro tissues of commercially important Coffea canephora were analyzed by using a high performance liquid chromatography and further confirmed with electrospray ionization mass spectrometry.
High content of serotonin (SER) (98.54 ± 5 μg/g) and melatonin (MEL) (115.25 ± 6 μg/g) were found in freshly harvested seeds
of C. canephora followed by zygotic embryo (65.25 ± 4 and 96.54 ± 5 μg/g fresh weight) and endosperm (34.08 ± 2 and 51.08 ± 4 μg/g fresh
weight) of ripened fruits. Similarly endogenous pools of SER and MEL were moderate in in vitro tissues of C. canephora, i.e. callus (25.85 ± 2 and 75.74 ± 4), somatic embryos (31.88 ± 2 and 19.30 ± 2 μg/g fresh weight) and in vitro regenerated
plant stalk (15.78 ± 1 and 38.25 ± 3 μg/g fresh weight), respectively. In view of significant levels of both SER and MEL in
various tissues and beans of Coffea, further investigations on their physiological role needs to be investigated. 相似文献
7.
In vivo test systems for the quantitative and qualitative analysis of the biological activity of phytoestrogens 总被引:3,自引:0,他引:3
Diel P Schmidt S Vollmer G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,777(1-2):191-202
Many compounds of plant origin with the ability to bind to the estrogen receptor have been identified in the last decades. One of the most extensively used in vivo assays to characterise the estrogenic potency of these phytoestrogens and mechanisms of their action is the rodent uterotrophic assay. Various protocols exist for this test system, using immature, hypophysectomized, or ovariectomized rats and mice and oral or subcutaneous administration of the test compound. However, just monitoring the ability of a compound to stimulate uterine growth is not sufficient to characterize its estrogenicity. Over the last decades, an increasing number of estrogen sensitive tissues has been identified. Moreover, a variety of different molecular mechanisms have been discovered for the action of estrogens, including non-genomic actions. Therefore, an in vivo test design for estrogenicity should include an analysis of several estrogen sensitive parameters in different estrogen sensitive tissues. To distinguish between agonistic and antagonistic properties of a substance, combinations of the test compound with estrogens and antiestrogens should be analyzed. A reasonable supplement to this enhanced uterotrophic assay are selected estrogen sensitive tumor models, which can be used to test for potential chemopreventive properties of phytoestrogens. 相似文献
8.
G. A. Pietersz Wenjun Li Violeta Popovski Julie-Anne Caruana Vasso Apostolopoulos Ian F. C. McKenzie 《Cancer immunology, immunotherapy : CII》1998,45(6):321-326
We have previously reported preclinical studies in mice of the human mucin 1 (MUC1) antigen covalently linked to the yeast
cell-wall mannan polysaccharide (MFP), and shown strong cellular responses of the T1 type using mice. We now describe the
optimum parameters for administration of MFP to obtain cellular immunity [as measured by the cytotoxic T cell precursor (CTLp)
frequency]. In dose/response studies, in which 1 μg–150 μg was given by the i.p. route, it was clear that doses of 1–7 μg
led to cellular and not humoral immunity; at doses above 7 μg humoral immunity prevailed with little cellular immunity - increasing
doses giving greater amounts of antibody. The most favoured routes of administration were intraperitoneal or intradermal immunisation,
which were substantially better than i.m., i.v.; s.c. administration was the worst. Three immunisations were necessary for
a maximum cellular response, further immunisation decreasing the CTLp frequency. Six different adjuvants were used with MFP
[complete and incomplete Freund’s adjuvant (CFA, IFA) Alum, Adjuprime, muramyl dipeptide (MDP) and glutaminyl-muramyl dipeptide
(GMDP)]; Alum, GMDP, MDP and IFA moderately increased the CTLp frequency, IFA being the best. Even though preclinical studies
of the immunogen in mice may not necessarily mirror the behaviour of the immunogen in humans, these studies demonstrate the
factors to be taken into account for phase I/II clinical trials.
Received: 8 July 1997 / Accepted: 4 September 1997 相似文献
9.
Scanning electron microscopy was used to evaluate the uterine luminal epithelium from ovariectomized rats treated with a single minimal physiological dose of clomiphene citrate, oestradiol-17 beta or progesterone. It was found that clomiphene treatment produced some ultrastructural surface features which were similar to those seen with both oestrogen and progesterone treatment, but in addition it produced features unique to clomiphene treatment. 相似文献
10.
Ersoy IH Koroglu BK Varol S Ersoy S Varol E Aylak F Tamer MN 《Biological trace element research》2011,143(2):619-624
Although there are many studies on effect of fluoride on trace elements in experimental animals, few studies exist on serum
trace elements levels in patients with endemic fluorosis. We aimed to determine the serum levels of trace elements including
serum copper (Cu), zinc (Zn), and serum levels of minerals including calcium (Ca), phosphorus (P), magnesium (Mg), sodium
(Na), potassium (K) in patients with endemic fluorosis. The study group consisted of 30 patients with endemic fluorosis (17
females, 13 males, mean age 33.53 ± 9.85 years). An age, gender, and body mass index matched 30 healthy volunteers comprised
control group (21 females, ten males with a mean age 33.93 ± 7.39 years). Urine fluoride levels of chronic fluorosis patients
were significantly higher than that of control subjects as expected (1.92 ± 0.10 mg/l vs. 0.41 ± 0.09 mg/l, respectively;
P < 0.001). Serum Cu levels (89.14 ± 16.77 μg/dL vs. 102.69 ± 25.04 μg/dL, respectively, P = 0.017), serum Zn levels (77.98 ± 20.58 μg/dL vs. 94.57 ± 35.87μg/dL, respectively, P = 0.032), and serum Mg levels (1.92 ± 0.18 mg/dL vs. 2.07 ± 0.31 mg/dL, respectively, p = 0.022) was significantly lower in chronic fluorosis patients than in controls. There were no statistically significant
differences between the fluorosis group and control group with respect to serum levels of Na, K, Ca, and P. We concluded that
chronic fluorosis is associated with reduced serum levels of Cu, Zn, and Mg. 相似文献
11.
Plasma molybdenum concentrations were determined in children, ages two to 12 yr, with and without phenylketonuria (PKU). Mean
plasma molybdenum concentrations did not differ significantly between the children with PKU (1.33±0.5 μg/L) and without PKU
(1.75±0.8 μg/L). Plasma molybdenum concentrations in both groups of children ranged from <1 to 3 μg/L.
When data from all children were combined and then separated based on gender, mean plasma molybdenum levels did not differ
significantly between 9 females (1.56±0.68 μg/L) and 12 males (1.58±0.76 μg/L). Data were also combined and mean (±SD) plasma
molybdenum concentrations calculated for age groups. Two children aged 1 to <4 yr had plasma molybdenum concentrations of
1.0 μg/L, and six children aged 4 to <7 yr had mean (±SD) plasma molybdenum concentrations of 1.5±0.8 μg/L. Eleven children
aged 7 to <11 yr had a mean plasma molybdenum concentration of 1.7±0.7 μg/L, and two children 11 to <14 yr had plasma molybdenum
concentrations of 1 μg/L and 2 μg/L. Plasma molybdenum concentrations did not differ significantly among children in the age
groups. 相似文献
12.
Estrogen and glucocorticoids are known to evoke opposing effects on the uterus. We analyzed the effects of dexamethasone (DEX)
on uterine sympathetic denervation elicited by short- and long-term exposure to estrogen of intact prepubertal rats. We also
studied the effects of DEX on the physiological degeneration of uterine sympathetic nerves at term pregnancy. Changes in innervation
were assessed quantitatively by using computer-assisted methods on uterine cryostat tissue sections stained for tyrosine hydroxylase.
At 24 h following treatment of prepubertal rats (25 days of age) with 1 μg or 2.5 μg estrogen, marked increases in uterine
size and reductions in the percentage nerve area were observed. Co-administration of DEX (4 mg/kg) attenuated both these short-term
estrogen-induced effects. Treatment of 19-day-old rats with a single dose of 25 μg estrogen provoked, at 26 days of age, a
54% reduction in the total nerve area. This reduction was abolished by the co-administration of nine doses of DEX (0.5 mg/kg)
at 18–26 days of age. Treatment of rats with the same regime of DEX alone increased the total nerve area by 46% of the control
values. Studies of control pregnant rats revealed the unexpected presence of intrauterine nerve fibers at term. Treatment
of pregnant rats with six doses of DEX (4 mg/kg) at 16–21 days of age had no effects on the density of uterine sympathetic
nerves. These results suggest that DEX has growth-promoting effects on immature uterine sympathetic nerves and may antagonize
the degenerative effects elicited by long-term exposure to estrogen.
This work was partially supported by PEDECIBA, Universidad de la República, Montevideo, Uruguay. The Third World Academy of
Sciences (TWAS) supported the visit of A.I. Frías to the Laboratorio de Biología Celular (IIBCE, Montevideo, Uruguay). 相似文献
13.
Bacteroids formed by Mesorhizobium ciceri CC 1192 in symbiosis with chickpea plants (Cicer arietinum L.) contained a single form of citrate synthase [citrate oxaloacetate-lyase (CoA-acetylating) enzyme; EC 4.1.3.7], which
had the same electrophoretic mobility as the enzyme from the free-living cells. The citrate synthase from CC 1192 bacteroids
had a native molecular mass of 228 ± 32 kDa and was activated by KCl, which also enhanced stability. Double reciprocal plots
of initial velocity against acetyl-CoA concentration were linear, whereas the corresponding plots with oxaloacetate were nonlinear.
The K
m value for acetyl-CoA was 174 μM in the absence of added KCl, and 88 μM when the concentration of KCl in reaction mixtures
was 100 mM. The concentrations of oxaloacetate for 50% of maximal activity were 27 μM without added KCl and 14 μM in the presence
of 100 mM KCl. Activity of citrate synthase was inhibited 50% by 80 μM NADH and more than 90% by 200 μM NADH. Inhibition by
NADH was linear competitive with respect to acetyl-CoA (K
is = 23.1 ± 3 μM) and linear noncompetitive with respect to oxaloacetate (K
is = 56 ± 3.8 μM and K
ii = 115 ± 15.4 μM). NADH inhibition was relieved by NAD+ and by micromolar concentrations of 5′-AMP. In the presence of 50 or 100 mM KCl, inhibition by NADH was apparent only when
the proportion of NADH in the nicotinamide adenine dinucleotide pool was greater than 0.6. In the microaerobic environment
of bacteroids, NADH may be at concentrations that are inhibitory for citrate synthase. However, this inhibition is likely
to be relieved by NAD+ and 5′-AMP, allowing carbon to enter the tricarboxylic acid cycle.
Received: 14 July 1999 / Accepted: 20 September 1999 相似文献
14.
The sialic acid/glycosaminoglycan ratio was determined in 35 coronary artery ectasia patients and 35 control subjects to determine
the possible role of fluoride in the etiology of the disease. The coronary artery ectasia patients and controls were selected
from subjects who underwent coronary angiography. The mean serum sialic acid level was significantly lower in patients with
coronary artery ectasia (CAE) than in controls (340.3 ± 28.6 vs. 427.0 ± 15.9 μg/mL, respectively; p < 0.001). The mean serum glycosaminoglycan level was significantly higher in patients with CAE than in controls (5,013.1 ± 158.6
vs. 3,833.6 ± 237.1 μg/mL, respectively; p < 0.001). The sialic acid/glycosaminoglycan ratio in patients with coronary artery ectasia was significantly lower than in
controls (0.068 ± 0.007 vs. 0.111 ± 0.005; p < 0.001). There was more than 38.7% reduction in this ratio in patients with CAE when compared with controls. We demonstrated
that chronic fluoride exposure has an important role in pathogenesis of coronary artery ectasia. 相似文献
15.
Calcium-dependent transglutaminase activity was found to be present in vaginal homogenates from adult cycling rats. Treatment
of immature or adult ovariectomized rats with oestradiol (0.1 μg/g body weight) resulted in 1.5–2-fold enhancement in the
enzyme activity. Progesterone treatment (0.1 μg/g body weight) decreased the enzyme activity. Analysis of amino acids produced
by proteolytic enzyme digestion of insoluble keratins from rat vaginal tissue indicated the presence of γ-glutamyl-ε-⥿sine
dipeptide (4 μmol/g protein) in this protein. These results suggest that oestradiol acts on vaginal tissue and induces the
activity of transglutaminase. This enzyme catalyses the formation of γ-glutamyl-ε-lysine crosslinks between keratin polypeptides
and thus leads to kerartization of the tissue. 相似文献
16.
Ayako Ueki Yukiko Fukushima Tetsuo Kimoto 《Virchows Archiv. B, Cell pathology including molecular pathology》1976,22(1):315-321
The presence of C3 receptor sites on the cell surfaces of WI-38 fibroblasts was reported in a previous paper. Here the effect of dexamethasone
sodium sulfate of C3 receptor site function was studied. The incubation of WI-38 fibroblasts with dexamethasone sodium sulfate produces the biphasic
mode of action, i.e., the growth-stimulating phase with low doses (90–230 μg/ml) and the growth-inhibiting phase with high
doses (450–900 μg/ml). The function of C3 receptor sites on WI-38 fibroblasts seems to be very stable and cannot be suppressed by the pretreatment of WI-38 fibroblasts
with dexamethasone in high concentrations, where the cell growth is inhibited. 相似文献
17.
Jerome Honnorat Michele Accominotti Christiane Broussolle Andree-Carole Fleuret Jean-Jacques Vallon Jacques Orgiazzi 《Biological trace element research》1992,32(1-3):311-316
Zinc status was assessed in 53 diabetic patients: 18 insulin-dependent diabetic patients (IDDM), 22 noninsulin-dependent diabetic
patients (NIDDM) treated with oral antidiabetic agents, and 13 insulin-treated, noninsulin-dependent diabetic patients (IRDM).
Plasma zinc concentrations were in the usual range for healthy subjects in these three groups (15.3±0.9 μmol/L). Urinary zinc
excretions were elevated in the IDDM group (18.3±4.1 μmol/24 h;p<0.01 vs normal) and in the NIDDM group (17.5±3.5 μmol/24 h;p<0.01 vs normal), but normal in the IRDM group (11.3±2.4 μmol/24 h). In 14 NIDDM patients treated with transient continuous
sc insulin injections, urinary zinc decreased from 16.5±2.2 μmol/24 h before insulin treatment to 11.5±0.3 μmol/24 h after
insulin treatment without any modification in plasma zinc concentrations. 相似文献
18.
Fatemi Naieni F Ebrahimi B Vakilian HR Shahmoradi Z 《Biological trace element research》2012,146(1):30-34
Premature graying of hair with unclear etiology, which is known as premature canities, is a common cause of referrals to the
dermatologists. We assessed the relationship between serum iron, copper, and zinc concentrations with premature canities.
This study was conducted on patients under 20 years old suffering from premature canities, having a minimum of ten gray hair
fibers, and referring to university hospitals of Isfahan (Iran). The results were compared with age–sex-matched controls.
Demographic data and disease characteristics were recorded for two groups. We studied serum iron, copper, and zinc concentrations
of 66 patients and 66 controls using atomic absorption and Ferrozine methods. The mean age of studied cases was 17.8 ± 2.0 years,
and the mean age of the onset of canities was 15.5 ± 3.2 years with no significant difference between males and females (P > 0.05). Serum copper concentration was significantly lower in patients compared with controls (90.7 ± 37.4 vs. 105.3 ± 50.2 μg/dL,
P = 0.048), but serum iron concentration was significantly lower in controls compared to patients (88.8 ± 39.5 vs. 108.3 ± 48.4 μg/dL,
P = 0.008). Also, there was no significant difference between patients and controls in serum zinc concentration (114.8 ± 67.8
vs. 108.2 ± 49.9 μg/dL, P = 0.285). According to these results, among copper, zinc, and iron, a low serum copper concentration may play a role in premature
graying of hairs in our society. Further studies are needed to find the underlying mechanism of this relationship. 相似文献
19.
John W. Einset Patricia T. Tomlinson 《In vitro cellular & developmental biology. Plant》1981,17(10):907-912
Summary Tissues formed in liquid cultures of tobacco (Nicotiana tabacum cv. Wisconsin 38) crown galls incited byAgrobacterium tumefaciens C58 were of three types: unorganized callus, organized teratoma, and organized normal appearing. These tissues contained
400±12, 410±17, and 614±53 μg nopaline/g fresh weight, respectively. Using [14C]arginine, methods were developed for measuring in vivo nopaline biosynthetic rates. Tissues were incubated in a low concentration
(i.e., 3 μM) of [14C]arginine to minimize disruption of the internal pool (approximately 140 μM free arginine). Radioactivity in the tissue was assayed and the specific radioactivity of free arginine, the precursor of
nopaline, was determined. The linear rate of incorporation of radioactivity into nopaline was used to calculate the following
biosynthetic rates (expressed as microgram nopaline per gram fresh weight per 24 h): callus, 14; teratoma, 21; normal appearing,
24. These results show conclusively that normal appearing tissues obtained from crown gall tumors can synthesize nopaline.
Abnormal growth and opine biosynthesis, therfore, can be expressed independently. 相似文献
20.
Five brands of antidiabetic herbal formulations as tablets, Diabetex, Divya Madhu Nashini, Jambrushila, Diabeticin, and Madhumeh Nashini, from different pharmacies were analyzed for six minor (Na, K, Ca, Cl, Mg, and P) and 20 trace (As, Ba, Br, Ce, Co, Cr, Cs,
Cu, Fe, Hg, La, Mn, Rb, Sb, Sc, Se, Sm, Th, V, and Zn) elements by thermal neutron irradiation followed by high-resolution
gamma ray spectrometry. Further Ni, Cd, and Pb were determined by atomic absorption spectrophotometry. Most elements vary
in a narrow range by a factor of 2–4 while a few others vary in a wide range, e.g., Na (0.05–0.67 mg/g), Mn (26.7–250 μg/g),
and V (0.26–2.50 μg/g). All the five brands contain K, Cl, Mg, P, and Ca as minor constituents along with mean trace amounts
of Cr (2.11 ± 0.67 μg/g), Cu (15.7 ± 7.11 μg/g), Fe (459 ± 171 μg/g), Mn (143 ± 23 μg/g), Se (238 ± 112 ng/g), and V (0.99 ± 0.93 μg/g).
Jambrushila is enriched in Na, Ca, Mg, Cl, Fe, Cu, Se, and Zn, essential nutrients responsible for curing diabetes. Dietary intake of
Mn, Fe, and Cu are greater than 10% of the recommended dietary allowance, whereas that for Zn and Se is less than 2%. Mean
contents of toxic elements (As, Cd, Hg, and Pb) were found below permissible limits except in Jambrushila. Cr and Zn were inversely correlated with r = −0.81, whereas Rb and Cs exhibit linear correlation (r = 0.93) in five brands. C, H, N analysis showed C ∼ 55%, H ∼ 12%, and N ∼ 2% with a total of ∼70% organic matter. However,
thermal decomposition studies at 700°C suggest less than 5% nonvolatile metal oxides. Herbal formulations contain minor and
trace elements in bioavailable forms that favorably influence glucose tolerance and possibly increase the body’s ability to
ameliorate development of diabetes. 相似文献