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1.
Aims: Previous studies suggested that Salvianolic acid B (SalB) has strong protective effect against cerebral ischemia. Recently, Sal B has been reported to enhance angiogenesis in vitro. Based on the information above, in this study we are interested in the effect of SalB on neurogenesis and angiogenesis. Methods:In vitro study, we used embryonic mouse (El6) primary cortical neural cultures. Neuron was recognized by anti-MAP2 with immunocytochemistry. Neurogenesis was tested with BrdU incorporation by ELSA method. SalB( 10 -6 -10 -8M) or vehicle was added to the culture medium 24 hrs before BrdU addition. In vivo, middle cerebral artery occlusion (MCAO) rats were used as focal cerebral ischemia model.  相似文献   

2.

Aim:

To evaluate the effect of lactoferrin (Lf) and transferrin (Tf) in brain targeting.

Methods:

Polymersomes (PSs), employed as vectors, were conjugated with Lf or Tf and were characterized by morphology, particle size, zeta potential, and surface densities of the Lf or Tf molecules. In vitro uptake of Lf-PS and Tf-PS by bEnd.3 cells was investigated using coumarin-6 as a fluorescent probe. In vivo tissue distribution and pharmacokinetics of 125I-Lf-PS and 125I-Tf-PS were also examined.

Results:

The mean particle size of PS, Lf-PS, and Tf-PS was around 150 nm and the zeta potential of the PSs was about -20 mV. Less than 0.12% of the coumarin was released from coumarin-6-loaded PS in 84 h indicating that coumarin-6 was an accurate probe for the PSs'' behavior in vitro. It was shown that the uptake of Lf-PS and Tf-PS by bEnd.3 cells was time-, temperature-, and concentration-dependent. Both Lf and Tf could increase the cell uptake of PSs at 37°C, but the uptake of Tf-PS was significantly greater than that of Lf-PS. In vivo tissue distribution and pharmacokinetics in mice revealed higher brain uptake and distribution of Tf-PS than Lf-PS, which was in accordance with in vitro uptake results. The drug targeting index (DTI) of Tf-PS with regard to Lf-PS was 1.51.

Conclusion:

Using a PS as the delivery vector and bEnd.3 cells as the model of the blood-brain barrier (BBB), Tf was more effective than Lf in brain targeting.  相似文献   

3.
Mutagenicity tests on epristeride in vitro and in vivo   总被引:1,自引:0,他引:1  
目的:评价治疗良性前列腺肥大的新药依立雄胺(Epr)的遗传影响.方法:1)鼠沙门氏菌体外回复突变试验测试能否诱发基因突变;2)CHL细胞染色体的损伤和畸变实验;3)ICR小鼠一次igEpr后测试是否导致骨髓嗜多染红细胞染色体的损伤;4)昆明种小鼠连续igEpr5d,30d后统计精子头部异常情况.结果:1)Epr不诱导细菌回复突变.2)CHL细胞染色体畸变低于3%不造成细胞染色体损伤.3)Epr不诱导小鼠嗜多染红细胞微核的形成.4)Epr高、中、低剂量组引起的头部畸形率分别为5.3%±2.7%,5.3%±1.9%,5.2%±1.2%,与对照组相比不引起显著的精子头部异常.结论:Epr在体内外实验中没有表现出遗传毒性.  相似文献   

4.
In Australia, death from cardiovascular diseases accounts for approximately 25% of all deaths. Epidemiological data suggest that the moderate consumption of alcoholic beverages may significantly reduce the risk of death from cardiovascular disease and indeed from all causes. Data also suggest that the ethanol component common to all alcoholic beverages confers primarily this protection and other data suggests that the wine-specific polyphenolic compounds confer additional protective effects. Is the amount and pattern of consumption really relevant? In vitro and in vivo studies have been undertaken recently, the results of which have both weakened and strengthened the traditional arguments cited on the type, amount and pattern of the consumption of alcoholic beverages. For example, the components of wine may act in concert rather than individually for cancer and cardioprotection, and more rather than less may be required for activity. This paper reviews relevant studies and evaluates critically their results, putting them in context with actual dietary practices rather than guidelines and policies.  相似文献   

5.
The aim of this work was to compare the intestinal absorption kinetics and the bioavailability of γ-tocotrienol (γ-T3) and α-tocopherol (α-Tph) administered separately as oil solutions to rats in vivo. Also, to explain the significant difference in the oral bioavailability of the compounds: (1) the release profiles using the dynamic in vitro lipolysis model, (2) the intestinal permeability and (3) carrier-mediated uptake by Niemann-Pick C1-like 1 (NPC1L1) transporter were examined. Absolute bioavailability studies were conducted after oral administration of γ-T3 or α-Tph prepared in corn oil to rats. In situ rat intestinal perfusion with ezetimibe (a NPC1L1 inhibitor) was performed to compare intestinal permeability. The in vitro interaction kinetics with NPC1L1 was examined in NPC1L1 transfected cells. While the in vitro release studies demonstrated a significantly higher release rate of γ-T3 in the aqueous phase, the oral bioavailability of α-Tph (36%) was significantly higher than γ-T3 (9%). Consequent in situ studies revealed significantly higher intestinal permeability for α-Tph compared with γ-T3 in rats. Moreover, the NPC1L1 kinetic studies demonstrated higher Vmax and Km values for α-Tph compared with γ-T3. Collectively, these results indicate that intestinal permeability is the main contributing factor for the higher bioavailability of α-Tph. Also, these results emphasize the potentially important role of intestinal permeability in the bioavailability of γ-T3, suggesting that enhancing its permeability would increase its oral bioavailability.  相似文献   

6.
Extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) and carbapenemase-producing Enterobacteriaceae (CPE) are widespread. Here we used the ‘One Health’ approach to determine knowledge gaps on ESBL-E and CPE in West and Central Africa. We searched all articles on ESBL-E and CPE in these African regions published in PubMed, African Journals Online and Google Scholar from 2000 onwards. Among the 1201 articles retrieved, we selected 165 studies (West Africa, 118; Central Africa, 47) with data from 22 of the 26 West and Central Africa countries. Regarding the settings, 136 articles focused only on humans (carriage and/or infection), 6 articles on humans and animals, 13 on animals, 1 on humans and the environment, 8 on the environment and 1 on humans, animals and environments. ESBL-E prevalence ranged from 11–72% in humans and 7–79% in aquatic environments (wastewater). In animals, ESBL-E prevalence hugely varied: 0% in cattle, 11–36% in chickens, 20% in rats, 21–71% in pigs and 32–75% in dogs. The blaCTX-M-15 gene was the predominant ESBL-encoding gene and was associated with plasmids of incompatibility groups F, H, K, Y, N, I1 and R. CPE were studied only in humans. Class B metallo-β-lactamases (NDM) and class D oxacillinases (OXA-48 and OXA-181) were the most common carbapenemases. Our results show major knowledge gaps, particularly on ESBL and CPE in animals and the environment, that might limit antimicrobial resistance management in these regions. The results also emphasise the urgent need to improve active surveillance programmes in each country and to support antimicrobial stewardship.  相似文献   

7.
Schedule-controlled responding was maintained under multiple fixed-interval, fixed-ratio schedules in pigeons and single fixed-ratio schedules in mice. In pigeons, clonidine, an 2-receptor agonist, produced dose-related decreases in responding under both fixed-interval and fixedratio schedules; fixed-interval responding was decreased at a lower dose than fixed-ratio responding. Low to intermediate doses of yohimbine, an 2-receptor antagonist, increased responding under the fixed-interval schedule without appreciably affecting responding under the fixed-ratio schedule; higher doses decreased responding under both schedules. In mice, both clonidine and yohimbine produced dose-related decreases in responding under fixed-ratio schedules. Decreases in response rates produced by clonidine were antagonized by low to intermediate doses of yohimbine. Decreases in response rates under fixed-ratio schedules produced by yohimbine were antagonized only slightly, if at all, by clonidine. Under the fixed-interval schedule, clonidine potentiated the response-rate increasing effects of intermediate doses of yohimbine and slightly antagonized the rate-decreasing effects. Although some effects of clonidine were antagonized by yohimbine, at no dose combination did performances completely resemble control performances. Prazosin, an 1-receptor antagonist, was ineffective both when administered alone and as an antagonist of the effects of clonidine. The behavioral effects of clonidine appeared to be mediated by 2 rather than 1 receptors. Additionally, yohimbine appears to have significant behavioral effects other than 2-antagonist actions.  相似文献   

8.
9.
Abstract

External gross observations of the eye and its adnexae, ocular reflexes, anterior ocular segment biomicroscopic examinations, fundic examinations performed with an indirect ophthalmoscope, and/or electroretinographic investigations (ERG) were carried out on 112 7-12-month-old Yucatan micropigs, on 18 6-8-week-old, and 81 2-10-month old Gottingen minipigs to evaluate the incidence of observed ocular abnormalities and to compare the ERG waves. A statistical comparison was performed for these findings.

The most important ocular defects were classified as remnants of embryological vascular tissue. The other findings were considered either as embryonic remnants or of nondeterminate etiology. The most noteworthy findings were, in decreasing order of incidence, for Yucatan micropigs, 6-8 week-old and 2-10-monfh-old Gottingen minipigs, respectively, hyaloid artery remnants (82.1%, 83.3%, and 46.3%), pupillary  相似文献   

10.
We describe the clinical response and the area under the concentration-time curve (AUC) of fluoxetine and serotonin levels in plasma and platelets in 10 depressive patients treated with 20 mg/day of fluoxetine for 30 days. Depression severity was assessed at baseline and after treatment by the Hamilton Rating Scale for Depression (HAM-D). "Good clinical response" was defined as a decrease of 50% or more of the total HAM-D score compared with baseline. Using this measure, patients were thus classified as "responders" or "nonresponders." For both groups we describe the AUC of fluoxetine and serotonin levels in plasma and platelets at baseline and after 30 days of treatment. We found different trends of biochemical parameters in the examined groups. In fact, after treatment responders showed, in comparison with nonresponders, higher levels of fluoxetine in platelets and lower levels in plasma; responders also showed lower concentrations of serotonin in platelets and higher concentrations in plasma.  相似文献   

11.

Background and purpose:

Cannabis is taken as self-medication by patients with inflammatory bowel disease for symptomatic relief. Cannabinoid receptor agonists decrease inflammation in animal models of colitis, but their effects on the disturbed motility is not known. (-)-Cannabidiol (CBD) has been shown to interact with Δ9-tetrahydrocannabinol (THC) in behavioural studies, but it remains to be established if these cannabinoids interact in vivo in inflammatory disorders. Therefore the effects of CBD and THC alone and in combination were investigated in a model of colitis.

Experimental approach:

The 2,4,6-trinitrobenzene sulphonic acid (TNBS) model of acute colitis in rats was used to assess damage, inflammation (myeloperoxidase activity) and in vitro colonic motility. Sulphasalazine was used as an active control drug.

Key results:

Sulphasalazine, THC and CBD proved beneficial in this model of colitis with the dose–response relationship for the phytocannabinoids showing a bell-shaped pattern on the majority of parameters (optimal THC and CBD dose, 10 mg·kg−1). THC was the most effective drug. The effects of these phytocannabinoids were additive, and CBD increased some effects of an ineffective THC dose to the level of an effective one. THC alone and in combination with CBD protected cholinergic nerves whereas sulphasalazine did not.

Conclusions and implications:

In this model of colitis, THC and CBD not only reduced inflammation but also lowered the occurrence of functional disturbances. Moreover the combination of CBD and THC could be beneficial therapeutically, via additive or potentiating effects.This article is part of a themed issue on Cannabinoids. To view the editorial for this themed issue visit http://dx.doi.org/10.1111/j.1476-5381.2010.00831.x  相似文献   

12.
LAWANDREGULATIONSSYSTEMChinahashadaneficientlawandregulationsregardingdrugsafety,eficacyandquality.Themainsofthoseareasfolows...  相似文献   

13.
Present status of phytotherapyPlant medicine is an important part oftraditional Chinese medicine.There are re-corded in the“Zhongyao Dacidian”(中药大辞典),5,767 kinds of traditional medicine,of which about a thousand kinds are providedwith profile of pharmacological actions.Most of the traditional pharmaceuticalpreparations are in form of pills,powders,softextracts and others manufactured by tradi-  相似文献   

14.
The in vitro binding of the naturally occurring -carbolines harman and norharman in their tritium-labelled forms to cell membranes from the rat brain and liver and from bovine adrenal medulla was investigated. Displacement of the specific [3H]harman binding in bovine adrenal medulla and rat liver by several -carbolines and monoamine oxidase (MAO) inhibitors revealed the pharmacological profile of a single, high-affinity binding site (K D 4.92±0.43 nmol/l, Bmax 8.47±0.17 pmol/mg protein; adrenal medulla) which corresponded to the active site of MAO type A (MAO-A). Similar characteristics have previously been found for brain tissue from rat, marmoset and pig. In order to determine the temperature dependence of the [3H]harman binding, the K D and Bmax values for rat cerebral cortex were calculated from the results of saturation experiments at 5 temperatures (range: 0°C–37°C). Whereas the Bmax values under all conditions were – 4 pmol/mg protein, the K D values, with increasing temperature, ranged from 3 nmol/l to 30 nmol/l. The calculated linear van't Hoff plot (-In K D against 1/T) suggested an enthalpy-driven binding of [3H]harman to MAO-A.At least three different [3H]norharman-binding sites were detected. In the rat forebrain, 85% of the specific binding (at about 2 nmol/l of [3H]norharman) can be attributed to a MAO binding site of type B: the binding is displaceable, in nmol/l concentrations by the potent and selective MAO-B inhibitors MDL 72,974A, R(–)-deprenyl and pargyline and, in mol/l concentrations, by S(+)-deprenyl and the potent and selective MAO-A inhibitors clorgyline, harmine, harman, harmaline, brofaromine 5-F--methyltryptamine. After suppression of the MAO binding sites with 1 mol/l clorgyline and mol/l R(–)-deprenyl, a second binding site was found. However, the binding at this site was biphasically displaceable by harman and norharman (Hill-slopes about 0.5 and 0.6, curvilinear Rosenthal plots) suggesting the presence of negative co-operativity or of two binding sites (states). A similar clorgyline/R(–)-deprenyl resistent single (Hill-slopes of displacement by norharman, harman and 6-hydroxy--carboline about unity; linear Rosenthal plots) high affinity binding site (K D 7.5±2 nmol/l, Bmax 130±30 fmol/mg protein) was found in bovine adrenal medullary cell membranes. A third quite different clorgyline/R(–)-deprenyl resistent high-affinity (K D14 nmol/l) and high-density (Bmax 10–30 pmol/mg protein) binding site was detected in the liver. The specific binding at this site was not displaceable by harman or most other substituted -carbolines or by tetrahydro--carbolines, but was displaced by norharman and several newly synthesized 6-substituted aromatic -carbolines (e.g. F-, CH3-, CH3O-, HO-). The [3H]norharman binding site in the liver is certainly not identical with any of the binding sites for MAO-inhibitors, benzodiazepines or sigma receptor ligands and is slightly enriched in the microsomal (P3) fraction whereas most of the specific [3H]harman binding was detected in the crude mitochondrial (P2) fraction. Correspondence to: T. May at the above address  相似文献   

15.
《Drug delivery》2013,20(7):346-353
With a view to improving the solubility and delivery characteristics of poorly water-soluble drugs, we prepared β-cyclodextrin-curcumin (βCD-C) inclusion complexes (hydrophilic curcumin) and entrapped both native curcumin (hydrophobic) and the complexes separately into liposomes; these were then assessed for in vitro cytotoxicity in lung and colon cancer cell lines. Optimization of curcumin entrapment within βCD was achieved, with the resultant βCD-C complexes prepared by methanol reflux. Inclusion complexes were confirmed using UV spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction. The water solubility of βCD-C complexes improved markedly (c.f. native curcumin) and successful entrapment of complexes into liposomes, prepared using a thin-film hydration approach, was also achieved. All the liposomal formulations were characterized for curcumin and βCD-C complex entrapment efficiency, particle size, polydispersity and stability at 2–8°C. Curcumin, βCD-C complex and their optimized liposomal formulations were evaluated for anticancer activity in lung (A-459) and colon (SW-620) cancer cell lines. All curcumin-containing formulations tested were effective in inhibiting cell proliferation, as determined via an MTT assay. The median effective dose (EC50) for all curcumin formulations was found to be in the low µM range for both lung and colon cancer cell lines tested. Our results confirm that βCD inclusion complexes of poorly water soluble drugs, such as curcumin can be entrapped within biocompatible vesicles such as liposomes, and this does not preclude their anticancer activity.  相似文献   

16.
1. The toxicokinetics of [3H]-α-solanine after oral (p.o.) and intravenous (i.v.) administration in rat and hamster were studied, in order to decide which is the most appropriate model in risk assessment studies. The i.v. Dose was 54 βg/kg; the oral dose was 170 βg/kg.

2. After i.v. Administration, the toxicokinetics of total radioactivity in blood were comparable in rat and hamster. However, the clearance of total radioactivity from plasma was more effective in rat than in hamster. The half-lives of distribution and of the terminal phase of unchanged α-solanine were not different between rat and hamster, whereas the systemic and metabolic clearance were, respectively, about 1.6 and 2.7 times higher in rat than in hamster. The clearance of unchanged α-solanine is more effective than of total radioactivity.

3. After p.o. Administration in rat and hamster, the mean bioavailability of total radioactivity is about 29 and 57%, respectively. The bioavailability of unchanged α-solanine is only 1.6 and 3.2%, respectively, when compared with i.v. administration.

4. T1/2el of α-solanine after p.o. Administration was in rats a factor of four and in hamsters a factor of two shorter than after i.v. Administration. A strong retention of radioactivity was seen in the hamsters after p.o. Administration; only 40% of the dose was excreted within 7 days versus 90% in rat.

5. Based on these and toxicological data from literature, it was decided that the hamster is a more appropriate model in (sub) chronic toxicity studies with α-solanine than the rat.  相似文献   

17.
β-blockers are a class of antihypertensive drugs that are used for the management of cardiac arrhythmias, cardioprotection after myocardial infarction (heart attack) and hypertension. They have revolutionized the medical management of angina pectoris and are recommended as first-line agents by national and international guidelines. Although β-blockers are still the cornerstone for the treatment of heart failure, some of the drugs in this category are prohibited in several sports requiring vehicle control and bodily movements as they reduce heart rate and tremors, and improve performance. As a result, urine analysis of β-blockers is mandatory in doping control and toxicological screening. The determination of plasma levels of β-blockers helps to ensure noncompliance in patients with persistent hypertonia to confirm the diagnosis of β-blocker poisoning and for therapeutic drug monitoring. This review provides a comprehensive account of various analytical methods developed for detection and quantitation of β-blockers in plasma and urine.  相似文献   

18.
Somehealthdataderivedfromdemographicsurveys,eg,lifeexpectancyandpopulationsizes,arecomprehensiveandreadilyavailable.Manyother...  相似文献   

19.
TheInternationalConferenceofHarmonization(ICH)guidelinesonGodClinicalPractice(GCP)weredevelopedwithconsiderationofthecurentg...  相似文献   

20.
Metastasis is the major hindrance in the treatment of all cancers, including laryngeal squamous cell carcinoma. Intensive researches are under way to identify the effective natural polyphenols with anti-metastatic ability for cancer treatment. Wheatgrass, an herbal plant has been reported to show anticancer effects. Hence, in this study, we aimed to analyze the anti-metastatic effect of methanol extract of wheatgrass (MEWG). The levels of metastatic marker proteins were determined by western blot. PI3K and AKT levels were determined by real time (RT)-PCR analysis. In silico molecular docking was done to check the interaction of the 14 components (identified by HPLC/GCMS) of MEWG with PI3K and AKT. MEWG effectively decreased the metastatic protein expressions, namely VEGF, MMP-9 and COX-2 and increased TIMP-2. RT-PCR results showed reduced m-RNA levels of both PI3K and AKT when compared to control. Molecular docking studies revealed interaction of most of the identified compounds of the extract with the important residues of PI3K and AKT. These findings indicate that MEWG inhibits metastasis and angiogenesis in Hep-2 cells possibly via PI3K/AKT due to the cumulative effect of polyphenols and other constituent present in extract. The compounds of the extract were also found to be directly involved in inhibition of AKT/PI3K, thus could help to restrain metastasis.  相似文献   

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