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1.
The use of the experimental model of the development of acute secondary immunodeficiency, accompanied by the redistribution of immunoglobulins from plasma to blood cells, for evaluating the effect of immunomodulation is substantiated. The preparation of proteolytic enzymes Wobenzym [correction of "Vobenzyme"] has been shown to produce significant and dose-dependent decrease the sorption of immunoglobulins on mouse cells in the process of swimming.  相似文献   

2.
A systematic synthesis of four natural epicatechin series procyanidin trimers [[4,8:4",8"]-2,3-cis-3,4-trans: 2",3"-cis-3",4"-trans: 2,3-trans-(-)-epi-catechin-(-)-epicatechin-(+)-catechin, [4,8:4",8"]-2,3-cis-3,4-trans: 2",3"-cis-3",4"-trans: 2,3-cis-tri-(-)-epicatechin: procyanidin C1, [4,8:4",8"]-2,3-cis-3,4-trans: 2",3"-trans-3",4"-trans: 2,3-trans-(-)-epicatechin-(+)-catechin-(+)-catechin: procyanidin C4, and [4,8:4",8"]-2,3-cis-3,4-trans: 2",3"-trans-3",4"-trans: 2,3-cis-(-)-epicatechin-(+)-catechin-(-)-epicatechin] is described. Condensation of (2R,3R,4S)-5,7,3'4'-tetra-O-benzyl-4-(2"-ethoxyethyloxy)flavan derived from (-)-epicatechin as an electrophile with the dimeric nucleophiles in the presence of TMSOTf followed by deprotection yielded trimers. Inhibitory activities on the Maillard reaction and antioxidant activity on lipid peroxide of the synthesized oligomers were also investigated.  相似文献   

3.
A benzil derivative: scandione, 2',2"-dihydroxy-4'-methoxy-4",5"-methylenedioxybenzil and two isoflavones: scandenal, 3'-formyl-4',5-dihydroxy-2",2"-dimethylchromeno-[6,7:5",6"]isoflavone and scanderone, 4',5-dihydroxy-3'-prenyl-2",2"-dimethylchromeno-[7,8:6",5"]isoflavone together with fifteen known compounds were isolated from the stem of D. scandens. Their structures were determined by spectroscopic methods. Radical scavenging, antibacterial and hypertensive activities of some of the compounds were investigated.  相似文献   

4.
The novel sialyl donor methyl (ethyl 4,7,8,9-tetra-O-acetyl-5-N,N-diacetylamino-3,5-dideoxy-2-thio-3-thiophenyl-D-erythro-beta-L-gluco-non-2-ulopyranosid)onate was used for glycosylation of a lactosyl acceptor to give the GM3-trisaccharide derivative in 83% yield. Introduction of an azido group at C-9" of the GM3-trisaccharide derivative, transformation into a glycosyl acceptor, and sialylation with the above mentioned novel sialyl donor gave a GD3-trisaccharide in 50% yield. Reduction of the azido group gave the corresponding amine, which underwent spontaneous lactamization to the GD3-[1"'-9"]-lactam in an overall yield of 86%. Removal of protecting groups of over five steps, followed by per-O-acetylation gave an acetylated GD3-[1"'-9"]-lactam TMSEt glycoside in 27% overall yield. The acetylated GD3-[1"'-9"]-lactam TMSEt glycoside is suitable for glycosylation of linker-arms and the resulting linker-glycosides are planned to be coupled to carrier proteins, thus providing immunogens for trial vaccinations against malignant melanoma.  相似文献   

5.
Activity of monoamine oxidase in the neurons of catecholamine-synthesizing nuclei of hypothalamic and brainstem of rabbits with different resistance of cardiovascular functions to emotional stress was studied by the Glenner et al. method. An acute experimental emotional stress was induced by non-periodic electric stimulation of the hypothalamic ventromedial nucleus and the skin in immobilized adult chinchilla rabbits. It was found that monoamine oxidase activity in the neurons of groups A5, A6, A7 and A14 under acute experimental emotional stress increased in rabbits "resistant"to stress and remained unchanged in rabbits "predisposed" to stress. The activity of monoamine oxidase in the neurons of group A12 remained unchanged in the rabbits "resistant"to stress and decreased in the rabbit "predisposed" to stress.  相似文献   

6.
Condensation of daunorubicin or its (13 R, S)-dihydro derivative with inosine dialdehyde in the presence of NaBH3CN yielded novel derivatives of anthracycline antibiotics with incorporated inosine residue: 3'-deamino-3'-[(2" R)-(hypoxanthyl-9)-(6" S)-hydroxymethylmorpholino-N4"]- daunorubicin and (13 R,S)-dihydro-3'-deamino-3'-[(2" R)-(hypoxanthyl-9)-(6" S)- hydroxymethylmorpholino-N4"]-daunorubicin. The compounds did not inhibit growth of Bacillus mycoides and were less cytotoxic in vitro and less toxic in vivo than the parent antibiotics.  相似文献   

7.

Purpose

To diagnose glaucoma based on spectral domain optical coherence tomography (SD-OCT) measurements using the ‘Random Forests’ method.

Methods

SD-OCT was conducted in 126 eyes of 126 open angle glaucoma (OAG) patients and 84 eyes of 84 normal subjects. The Random Forests method was then applied to discriminate between glaucoma and normal eyes using 151 OCT parameters including thickness measurements of circumpapillary retinal nerve fiber layer (cpRNFL), the macular RNFL (mRNFL) and the ganglion cell layer-inner plexiform layer combined (GCIPL). The area under the receiver operating characteristic curve (AROC) was calculated using the Random Forests method adopting leave-one-out cross validation. For comparison, AROCs were calculated based on each one of the 151 OCT parameters.

Results

The AROC obtained with the Random Forests method was 98.5% [95% Confidence interval (CI): 97.1–99.9%], which was significantly larger than the AROCs derived from any single OCT parameter (maxima were: 92.8 [CI: 89.4–96.2] %, 94.3 [CI: 91.1–97.6] % and 91.8 [CI: 88.2–95.4] % for cpRNFL-, mRNFL- and GCIPL-related parameters, respectively; P<0.05, DeLong’s method with Holm’s correction for multiple comparisons). The partial AROC above specificity of 80%, for the Random Forests method was equal to 18.5 [CI: 16.8–19.6] %, which was also significantly larger than the AROCs of any single OCT parameter (P<0.05, Bootstrap method with Holm’s correction for multiple comparisons).

Conclusions

The Random Forests method, analyzing multiple SD-OCT parameters concurrently, significantly improves the diagnosis of glaucoma compared with using any single SD-OCT measurement.  相似文献   

8.
Chinchillas have become a preferred animal model for studying otitis media, and are also useful in studying insulin release, gastrin physiology, intestinal infection, and hepatocellular pathophysiology. Immunopathologic studies in the model, however, have been limited by absence of specific antibody reagents against chinchilla immunoglobulins. We describe a method for preparing isotype-specific rabbit antibodies against the heavy-chain components of chinchilla immunoglobulins G, M, and A. Chromatographic techniques were used to isolate chinchilla immunoglobulins from serum and breast milk; heavy-chain fractions were isolated and used as antigens to produce isotype-specific antibodies in New Zealand White rabbits. Enzyme-linked immunosorbent assay of these antisera disclosed anti-light chain cross-reactivity, which was removed by affinity chromatography. The isolation and affinity purification techniques were highly reproducible. The availability of these reagents should greatly enhance the utility of the chinchilla in modeling human disease.  相似文献   

9.
In Memory of Max Gluckman
Theories of strategic interaction have been offered as a cure for the failings of structural functionalism and currently enjoy considerable influence in social anthropology. Employing in illustration Barth's Models of Social Organization, this essay argues that interactionism's focus on the individual, rather than on the group, issues from the presupposition of physicalism and makes it impossible to account for values and socioculture as such. A dialectical approach is urged . [transactional analysis, theory, dialectical approach, the "individual"]  相似文献   

10.
It has been shown in experiments on rabbits that alpha-and beta-adrenoblockers, and lithium chloride solution exert different effect on intraocular tension of healthy animals with experimental glaucoma and transitory hypertension. The beta-blockker obsidan decreases the tension in experimental glaucoma. Pretreatment with the drug prevents the development of glaucoma. On the contrary, the alpha-blocker pirroxan promotes the development of glaucoma and does not elicit any hypotensive therapeutic effect. The drug-induced decrease in intraocular tension was recorded in healthy animals and in rabbits with transitory hypertensin of the eye. The hypotensive effect of lithium was noted only in the animals with experimental glaucoma. The role of alpha-and beta-adrenergic receiption in the pathogenesis of glaucoma is discussed.  相似文献   

11.
The influence of intracellular sodium concentration ( [Na+]i) on the number of Na(+)-K(+)-ATPase pumps was examined in cortical collecting tubules (CCD) of kidneys from rabbits in different aldosterone conditions. Specific [3H]ouabain binding was measured in isolated CCD with various [Na+]i. Experiments were performed on adrenalectomized rabbits receiving only a substitutive dose of dexamethasone and on adrenalectomized rabbits replete with aldosterone. In aldosterone-replete rabbits, the number of binding sites increased linearly with [Na+]i, from 16 fmol/nl tubular volume at 15 mM Na+i to 39 fmol/nl tubular volume at 140 mM Na+i. Neither actinomycin D (5 microM) nor cycloheximide (10 microM) prevented this [Na+]i-dependent increase. In adrenalectomized rabbits, the number of ouabain-binding sites was reduced and did not increase with [Na+]i. These results are in favor of the presence of a "latent" pool of pumps in CCD, rapidly recruited under [Na+]i influence. Aldosterone appears to be required for the constitution and/or activation of this pool.  相似文献   

12.
Chromogranin B (CHGB) is the major matrix protein in human catecholamine storage vesicles. CHGB genetic variation alters catecholamine secretion and blood pressure. Here, effective Chgb protein under‐expression was achieved by siRNA in PC12 cells, resulting in ~ 48% fewer secretory granules on electron microscopy, diminished capacity for catecholamine uptake (by ~ 79%), and a ~ 73% decline in stores available for nicotinic cholinergic‐stimulated secretion. In vivo, loss of Chgb in knockout mice resulted in a ~ 35% decline in chromaffin granule abundance and ~ 44% decline in granule diameter, accompanied by unregulated catecholamine release into plasma. Over‐expression of CHGB was achieved by transduction of a CHGB‐expressing lentivirus, resulting in ~ 127% elevation in CHGB protein, with ~ 122% greater abundance of secretory granules, but only ~ 14% increased uptake of catecholamines, and no effect on nicotinic‐triggered secretion. Human CHGB protein and its proteolytic fragments inhibited nicotinic‐stimulated catecholamine release by ~ 72%. One conserved‐region CHGB peptide inhibited nicotinic‐triggered secretion by up to ~ 41%, with partial blockade of cationic signal transduction. We conclude that bi‐directional quantitative derangements in CHGB abundance result in profound changes in vesicular storage and release of catecholamines. When processed and released extra‐cellularly, CHGB proteolytic fragments exert a feedback effect to inhibit catecholamine secretion, especially during nicotinic cholinergic stimulation.

  相似文献   


13.
Mandibular dysmorphology in unilateral coronal synostosis has been recognized clinically. In patients with unilateral coronal synostosis, the chin point deviates away from the affected side. To investigate whether this mandibular asymmetry resolves after correction of unilateral coronal synostosis, familial nonsyndromic rabbits were used. Rabbits with unilateral coronal synostosis that underwent "correction" with resection of the affected suture were compared with "uncorrected" rabbits with unilateral coronal synostosis and normal, wild-type rabbits (n = 36; three equal groups of 12). Serial lateral cephalograms obtained at 10, 25, 42, and 84 days showed no asymmetries in wild-type rabbits and progressive asymmetries in the ramal height and mandibular length in uncorrected unilateral coronal synostosis rabbits. However, in corrected unilateral coronal synostosis rabbits, existing asymmetries at 10 and 25 days improved by 42 days and were not seen by maturity, at 84 days. In dry, mature, mandibular specimens, wild-type rabbits showed equal side-to-side measurements and uncorrected unilateral coronal synostosis rabbits showed the following on the affected side: longer ramal height (15 percent), shorter ramal width (13 percent), longer body height (10 percent), and shorter body width (13 percent). By contrast, the corrected unilateral coronal synostosis specimens showed no side-to-side differences in 10 of 11. There were no asymmetries in condylar shape or condylar volume in any of the three groups. Cranial base measurements showed asymmetries of the uncorrected unilateral coronal synostosis specimens that were consistent with an anteriorly positioned glenoid fossa on the affected side. However, only one of 11 corrected unilateral coronal synostosis specimens showed similar cranial base asymmetries. The data showed that mandibular asymmetries in nonsyndromic, familial rabbits with unilateral coronal synostosis are progressive with growth but improve after correction of synostosis.  相似文献   

14.
Studies have been made on the content of adrenalin and noradrenalin in the nervous fibers and ganglia of the sympathetic nervous system of cats and rabbits during a postnatal life. In all the structures investigated, high catecholamine content was found within the first month of life on the animals. On further development, total catecholamine content decreases. Age changes in catecholamine content of preganglionic sympathetic fibers and different sympathetic ganglia indicate an effective adrenergic regulation in early postnatal ontogenesis of cats and rabbits.  相似文献   

15.
目的 总结兔先天性青光眼的临床特点。方法 对先天性青光眼兔和正常兔进行临床观察,研究其在眼压、眼球结构、视功能方面的变化。结果 青光眼兔的眼压明显升高,角膜直径变大,前房变深,眼轴变长,房角变宽,眼底视乳头损害明显,视觉诱发电位明显异常。结论 兔先天性青光眼的房水排泄障碍部位可能在小梁,兔眼球壁对高眼压的耐受力弱,在高眼压下容易出现眼球扩张,视功能损害。  相似文献   

16.
A novel flavonoid named mopanolchin (1), together with seven known flavonoids, was isolated by various chromatographic techniques and spectroscopic methods from the EtOAc extract of the roots of Lysidice rhodostegia Hance. The structure of the new compound was elucidated as 1"-(4-hydroxy-3, 5-dimethoxy)phenyl-2"-hydroxymethyl-dioxino [4', 5',1", 2"]mopanol (1) on the basis of spectral analysis.The known compounds were identified as (-)-epicatechin-3-O-gallate (2), epicatechin (3), naringenin (4),eriodictyol (5), luteolin (6), 7, 3', 4'-trihydroxyflavone (7) and (-)-robinetinidol (8).  相似文献   

17.
Designed and synthesized thirty-two 2,4-diaryl-5,6-dihydro-1,10-phenanthroline and 2,4-diaryl-5,6-dihydrothieno[2,3-h] quinoline derivatives as rigid analogs of 2,4,6-trisubstituted pyridines were evaluated for topoisomerase I and II inhibitory activities as well as cytotoxicities against several human cancer cell lines. Structure-activity relationship study showed that [2,2';6',2"]-terpyridine skeleton is important for the cytotoxicity against several human cancer cell lines.  相似文献   

18.
In isolated bovine adrenal medullary cells, the phorbol ester 12-O-tetradecanoyl phorbol 13-acetate (TPA), an activator of protein kinase C, stimulated [14C]catecholamine synthesis from [14C]tyrosine, but not from [14C]DOPA. This stimulatory effect of TPA on [14C]catecholamine synthesis was not dependent upon extracellular Ca2+, and TPA did not affect the uptake of 45Ca2+ or the release of catecholamine by the cells. TPA also did not affect the intracellular cyclic AMP (cAMP) level. 4 alpha-Phorbol 12, 13-didecanoate, which is not an activator of protein kinase C, did not stimulate the synthesis of [14C]catecholamine from [14C]tyrosine. The stimulatory effect of TPA on [14C]catecholamine synthesis was additive with that of carbamylcholine, but not with that of dibutyryl cAMP (DB-cAMP). From these results, it was suggested that protein kinase C is involved in the regulation of tyrosine hydroxylase activity and that this regulatory mechanism might be similar to that involving cAMP.  相似文献   

19.
The effect of lipid lowering agents of plant origin garlic oil and guggulipid on the levels of catecholamine and dopamine Β-hydroxylase activity of normal and cholesterol fed rabbit tissues has been studied. The catecholamine levels and enzyme activity were found to be decreased in cholesterol (500 mg/kg body wt) fed animals. The feeding of garlic oil (5 mg/kg body wt) and guggulipid (100 mg/kg body wt) an exudate ofCommiphora mukul, to normal rabbits caused significant increase in the dopamine-Β-hydroxylase activity and catecholamine levels, while the feed helped the hypercholesterolemic rabbits to recover the decrease in catecholamine biosynthesis C.D.R.I. Communication No. 3435.  相似文献   

20.
Several studies have measured the rate of catecholamine clearance, metabolism, and tissue accumulation in fish. However, no information is available on the effect of repeated stress or high circulating catecholamine levels on catecholamine clearance and metabolism. We measured the clearance and metabolism of [3H]-epinephrine (approximately 0.1 g·kg-1) in SW-acclimated rainbow trout subjected to acute (five injections in 1 day) and chronic (4 days; five injections per day) administration of 4.0 g·kg-1 epinephrine or saline. In addition, a saturation experiment, where 4.0 g·kg-1 of unlabelled epinephrine was injected concurrently with [3H]-epinephrine, investigated whether catecholamine clearance and metabolism are affected by high circulatin levels. Neither the rate constants for catecholamine clearance, nor the post-injection proportions of unmetabolised [3H]-epinephrine, deaminated [3H]-epinephrine and O-methylated [3H]-epinephrine were affected by the acute or chronic injection protocols. The concurrent injection of [3H]-epinephrine and 4.0 g·kg-1 of unlabelled epinephrine resulted in an elevated postinjection 3H:14C ratio, but increased proportions of O-methylated [3H]-epinephrine and reduced proportions of unmetabolised [3H]-epinephrine. We conclude that in fish (1) catecholamine clearance and metabolism are unlikely to be compromised by repeated exposure to acute stressors; (2) catecholamine extraction and/or metabolism is enhanced when circulating levels are high; and (3) there is a marked capacity to rapidly (minutes) clear and inactivate catecholamines that are released in response to stressful stimuli.Abbreviations CA catecholamines - dpm disintegrations per minute - MAO monoamine oxidase - COMT catecholamine-O-methyltransferase - MOPEG 3-methoxy-4-hydroxyphenylglycol - VMA 3-methoxy-4-hydroxymendelic acid - SW seawater - HPLC high-performance liquid chromatography  相似文献   

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