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1.

OBJECTIVE:

Available chemotherapy presents poor control over the development of metastatic melanoma. FTY720 is a compound already approved by the Food and Drug Administration for the treatment of patients with multiple sclerosis. It has also been observed that FTY720 inhibits tumor growth in vivo (experimental models) and in vitro (animal and human tumor cells). The aim of this study was to evaluate the effects of FTY720 on a metastatic melanoma model and in tumor cell lines.

METHODS:

We analyzed FTY720 efficacy in vivo in a syngeneic murine metastatic melanoma model, in which we injected tumor cells intravenously into C57BL/6 mice and then treated the mice orally with the compound for 7 days. We also treated mice and human tumor cell lines with FTY720 in vitro, and cell viability and death pathways were analyzed.

RESULTS:

FTY720 treatment limited metastatic melanoma growth in vivo and promoted a dose-dependent decrease in the viability of murine and human tumor cells in vitro. Melanoma cells treated with FTY720 exhibited characteristics of programmed cell death, reactive oxygen species generation, and increased β-catenin expression. In addition, FTY720 treatment resulted in an immunomodulatory effect in vivo by decreasing the percentage of Foxp3+ cells, without interfering with CD8+ T cells or lymphocyte-producing interferon-gamma.

CONCLUSION:

Further studies are needed using FTY720 as a monotherapy or in combined therapy, as different types of cancer cells would require a variety of signaling pathways to be extinguished.  相似文献   

2.

OBJECTIVE:

To explore the use of β-lactoglobulin polymerized using microbial transglutaminase and heating to identify whether protein polymerization could reduce in vivo allergenicity and maintain in vitro and ex vivo immunoreactivity for use in tolerance-induction protocols.

METHODS:

Based on previous protocols applied in mice and children, we performed in vivo challenges (using a skin prick test) with native and polymerized β-lactoglobulin in adult patients with an IgE-mediated allergy to β-lactoglobulin. In vitro humoral immunoreactivity was analyzed using immunoblotting. Cell-mediated immunoreactivity was analyzed using ex vivo challenges with native and polymerized β-lactoglobulin and monitored by leukocyte adherence inhibition tests.

RESULTS:

The skin tests demonstrated that there was a significant reduction in immediate cutaneous reactivity after polymerization. Polymerization did not decrease the immunoblotting detection of s-IgE specific to β-lactoglobulin. Cell-mediated immunoreactivity, as assessed by ex vivo challenges and leukocyte adherence inhibition tests, did not exhibit significant differences between leukocytes challenged with native versus polymerized β-lactoglobulin.

CONCLUSIONS:

The polymerization of β-lactoglobulin decreased in vivo allergenicity and did not decrease in vitro humoral or ex vivo cell-mediated immunoreactivity. Therefore, we conclude that inducing polymerization using transglutaminase represents a promising technique to produce suitable molecules for the purpose of designing oral/sublingual tolerance induction protocols for the treatment of allergies.  相似文献   

3.

Background

Herb-drug interaction (HDI) has been regarded as a key factor limiting the clinical application of herbs and drugs.

Aims

Potential baicalein-zidovudine (AZT) interaction was predicted in the present study.

Methods

In vitro evaluation of baicalein''s inhibition towards human liver microsomes (HLMs)-catalyzed metabolism of zidovudine (AZT) was performed. Dixon and Lineweaver-Burk plots were used to determine the inhibition kinetic type, and second plot with the slopes from Lineweaver-Burk plot versus the concentrations of baicalein was employed to calculate the inhibition parameter (Ki). In combination with the in vivo concentration of baicalein, in vitro-in vivo extrapolation (IVIVE) was carried out to predict in vivo baicalein-AZT interaction.

Results

Competitive inhibition of baicalein towards AZT metabolism was demonstrated, and the Ki value was calculated to be 101.2 µM. The value of AUCi/AUC was calculated to be 2.

Conclusion

Potential baicalein-AZT interaction was indicated in the present study, indicating the need for monitoring when AZT is co-administrated with baicalein or baicalein-containing herbs.  相似文献   

4.

OBJECTIVE:

To compare normal and delayed bone healing by measuring ultrasound conduction velocity across the bone callus.

METHODS:

A model of transverse linear and 5 mm resection osteotomies of sheep tibiae was used. Fourteen sheep were operated on and were divided into two groups of seven according to osteotomy type. The procedure was performed on the right tibiae and the intact left tibiae were used as controls. The transverse and axial ultrasound velocities were measured at 30-day intervals for 90 days, after which the animals were killed and both the right and left tibiae were resected for in vitro biomechanical analysis.

RESULTS:

Both the transverse and axial ultrasound velocities progressively increased, but the increase was smaller for the delayed union that resulted from the resection osteotomy. The mechanical resistance was higher for the normally healed tibiae that resulted from a linear osteotomy; this result closely correlated with the ultrasound velocity results. Significant differences were found for the comparisons between the intact and operated tibiae in both groups and between the groups for both the transverse and axial ultrasound velocities, but the differences were greater for the latter.

CONCLUSION:

We conclude that in vivo transverse and axial ultrasound velocities provide highly precise information about the healing state of both linear and resection diaphyseal osteotomies, but the axial ultrasound velocity most likely has greater discriminatory power. This method has the potential for clinical application in humans.  相似文献   

5.

Introduction

It is known that periodontal ligament stem cells (PDLSCs) can differentiate into cementoblast-like cells, adipocytes and collagen-forming cells. However, whether PDLSCs are able to differentiate into Schwann cells and which method is best for their neural induction remain unknown. We attempted to determine whether PDLSCs possessed the potential for neural differentiation in vitro.

Materials and methods

We isolated and multiplied PDLSCs from periodontal ligaments obtained from the teeth (n = 24) of 8-month-old beagle dogs. Four protocols with different chemicals and growth factors were adopted to induce the PDLSCs to differentiate into Schwann cells. Immunochemistry, RT-PCR and qRT-PCR were performed to investigate the in vitro neural differentiation potential of PDLSCs.

Results

We compared the 4 different protocols and showed that all 4 protocols could successfully induce PDLSCs to express nestin, GFAP and S100, markers for Schwann cells. Further, qRT-PCR revealed relative differences in the expression levels of these 3 genes in differentiated PDLSCs obtained by different protocols.

Conclusions

We conclude that PDLSCs have neural/glial differentiation potential in vitro and that neural/glial differentiation can be induced in PDLSCs if suitable protocols are followed. We also found that supplementing the growth medium with suitable growth factors is more effective than applying chemicals alone. While nerve growth factor is more effective than platelet-derived growth factor for inducing neural/glial differentiation in PDLSCs, pre-induction of PDLSCs with dimethyl sulphoxide yields better results than those obtained with all-trans-retinoic acid.  相似文献   

6.

Introduction

Two functional single nucleotide polymorphisms (SNPs) in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, C677T and A1298C, lead to decreased enzyme activity and affect chemosensitivity of tumour cells.

Material and methods

We evaluated these two common polymorphisms and breast cancer risk association in an Iranian sporadic breast cancer population-based case-control study of 294 breast cancer cases and 306 controls using a PCR-RFLP-based assay.

Results

Analyses of affected and controls show that homozygote genotype MTHFR 677CC has the highest frequency in both groups (28.3% in patients and 25.3% in control group). Genotype MTHFR 677CT and genotype MTHFR 1298AC were found to be statistically significant risk factors in our population (odds ratio: 1.6, 95% CI: 1.019-2.513, p = 0.041; and odds ratio: 2.575, 95% CI: 1.590-4.158, p = 0.001 respectively).

Conclusions

We can conclude based on the results of our study that a significant association between breast cancer and C677T and A1298C polymorphism might exist.  相似文献   

7.

Background

Moringa stenopetala, Baker f. (Moringaceae) is used for food and medicine in Southern Ethiopia.

Objective

To substantiate the hypotensive effect of M. stenopetala in vivo and in vitro.

Methods

An in vivo experiment was carried out on male guinea pigs anaesthetized with pentobarbital. The arterial blood pressure was recorded from a carotid artery filled with heparinized saline via an arterial cannula connected to a pressure transducer. For the in vitro experiment the descending thoracic aorta was removed and kept moistened in Krebs-Henseleit solution and then mounted in a 20ml tissue bath maintained at 37°C and bubbled with a mixture of 95% oxygen and 5% carbon dioxide.

Results

Crude aqueous leaf extract of M. stenopetala caused significant fall in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial blood pressure (MABP) at doses of 10, 20, 30 and 40 mg/kg in normotensive anaesthetized guinea pigs (n = 12). The effect might have been mediated by non-autonomic nervous system as the effect is not altered by atropine and propranolol. The extract also caused significant dose and time dependent inhibition of K+ induced contraction on guinea pig aorta.

Conclusion

M.stenopetala has blood pressure lowering effect substantiating the use of the plant in traditional medicine.  相似文献   

8.

Background

Inhibition of drug-metabolizing enzymes (DMEs) has been regarded as one of the most important reason for clinical drug-drug interaction.

Aim

The aim of the present study is to evaluate the inhibition of bakuchiol towards UDP-glucuronosyltransferase (UGT) 2B isoforms.

Methods

In vitro recombinant UGT2B-catalyzed 4-methylumbelliferone glucuronidation was used as the probe reaction. Dixon plot and Lineweaver-Burk plot were employed to determine the inhibition kinetic type, and nonlinear regression of data was utilized to calculate the inhibition kinetic parameter (Ki). In vitro-in vivo extrapolation (IVIVE) was carried out to predict in vivo inhibition magnitude.

Results

Among the tested UGT2B isoforms, UGT2B7 was inhibited by the strongest intensity. The noncompetitive inhibition was demonstrated by the results obtained from Dixon plot and Lineweaver-Burk plot. The Ki value was calculated to be 10.7 µM. In combination with the reported concentration after an intravenous administration of bakuchiol (15 mg/kg) in rats, the high risk of in vivo inhibition of bakuchiol towards UGT2B7-catalyzed metabolism of drugs was indicated.

Conclusion

All these results provide an important information for the risk evaluation of the clinical utilization of bakuchiol.  相似文献   

9.

Introduction:

Mutations in the leucine-rich repeat kinase 2 gene (LRRK2 or Dardarin) are considered to be a common cause of autosomal dominant and sporadic Parkinson´s disease, but the prevalence of these mutations varies among populations.

Objective:

to analyzed the frequency of the LRRK2 p.G2019S mutation (c.6055 G>A transition) in a sample of Colombian patients.

Methods:

In the present study we have analyzed the frequency of the LRRK2 p.G2019S mutation in 154 patients with familial or sporadic Parkinson Disease, including early and late onset patients, and 162 normal controls.

Results:

Our results show occurrence of this mutation in two cases (2/154, 1.3%) with classical Parkinson´s signs, and one completely asymptomatic control (1/162, 0.6%).

Conclusion:

The p.G2019S mutation is not an important causal factor of Parkinson Disease in Colombia having similar frequencies to those reported in other Latin American populations.  相似文献   

10.

Background:

The hallmark of tuberculosis is the granuloma, an organized cellular accumulation playing a key role in host defense against Mycobacterium tuberculosis. These structures sequester and contain mycobacterial cells preventing active disease, while long term maintenance of granulomas leads to latent disease. Clear understanding on mechanisms involved in granuloma formation and maintenance is lacking.

Objective:

To monitor granuloma formation and to determine gene expression profiles induced during the granulomatous response to M. tuberculosis (H37Ra).

Methods:

We used a previously characterized in vitro human model. Cellular aggregation was followed daily with microscopy and Wright staining for 5 days. Granulomas were collected at 24 h, RNA extracted and hybridized to Affymetrix human microarrays.

Results:

Daily microscopic examination revealed gradual formation of granulomas in response to mycobacterial infection. Granulomatous structures persisted for 96 h, and then began to disappear.

Conclusions:

Microarray analysis identified genes in the innate immune response and antigen presentation pathways activated during the in vitro granulomatous response to live mycobacterial cells, revealing very early changes in gene expression of the human granulomatous response.  相似文献   

11.

Purpose

This study aimed to evaluate the preventive effects of Camellia sinensis var. assamica (CSVA) on diabetic nephropathy in in vitro and in vivo models.

Materials and Methods

MDCK cells were incubated with 1 mM of oxalate with or without different concentrations of CSVA, then MTT and malondialdehyde (MDA) assays were performed to investigate the preventive effects of CSVA on oxalate-induced cytotoxicity and oxidative stress. Thirty male db/db mice were divided into three groups. Group 1 were fed AIN-93G ad libitum; group 2 were fed AIN-93G mixed with 10% fermented CSVA ad libitum; group 3 were fed AIN-93G mixed with 10% non-fermented CSVA ad libitum. The mice were sacrificed 14 weeks later, and the serum glucose level, 24-hour urine chemistry, and morphological changes in the kidneys were examined.

Results

As CSVA concentrations increased, viable MDCK cells increased in concentration. MDA production decreased over time in the CSVA treated group. The creatinine clearance of group 3 was lower than those of groups 1 and 2. The amount of urine microalbumin and protein in group 1 were higher than those in groups 2 and 3. Also, more glomerulus basement membrane foot processes were preserved in groups 2 and 3.

Conclusion

In conclusion, CSVA has beneficial preventive tendencies towards diabetic nephropathy in both in vitro and in vivo models.  相似文献   

12.

Background

The relatively little resistance to quinine globally has led to an increase in its use in P. falciparum malaria especially in multi-drug resistant strains.

Objective

To evaluate the physicochemical and equivalency of three brands of quinine sulphate tablets available in South Western region of Nigeria.

Methods

The pharmaceutical and chemical equivalence of three brands of quinine sulphate tablets were assessed through the evaluation of some biopharmaceutical parameters and active drug content.

Results

All the brands complied with the official specification for uniformity of weight. Two of the brands (A & B) gave similar crushing strengths while the third brand (C) gave a much lower value. Similarly all the brands complied with the official specification of disintegration test but the obtained values were statistically different (p<0.05). The T70 obtained from the dissolution rate profile was less than 45 minutes for the three brands, although A and B were not statistically different but C was statistically from A and B. The quinine content of brands B and C are within the official specification however brand A with percentage content of 110±1.3%w/w, is above the specification while it is statistically different from the other brands.

Conclusion

Brands B and C could be regarded as chemical equivalent, but they are not biopharmaceutical equivalents, on the other hand, brands A and B may be regarded as biopharmaceutical equivalents but not chemical equivalent.  相似文献   

13.

Objective:

To determine the in vitro toxicity of different concentrations of sevoflurane in cells exposed to X-ray.

Methods:

The genotoxic effects of sevofluorane were studied by means of the micronucleus test in cytokinesis-blocked cells of irradiated human lymphocytes. Subsequently, its cytotoxic effects on PNT2 (normal prostate) cells was determined using the cell viability test (MTT) and compared with those induced by different doses of X-rays.

Results:

A dose- and time-dependent cytotoxic effect of sevofluorane on PNT2 cells was determined (p >0.001) and a dose-dependent genotoxic effect of sevofluorane was established (p >0.001). Hovewer, at volumes lower than 30 μL of sevofluorane at 100%, a non-toxic effect on PNT2 cells was shown.

Conclusion:

Sevofluorane demonstrates a genotoxic capacity as determined in vitro by micronucleus test in cytokinesis-blocked cells of irradiated human lymphocytes.  相似文献   

14.

OBJECTIVE:

This study aims to evaluate the production of interferon-gamma and interleukin-10 by stimulated peripheral blood mononuclear cells isolated from patients with supraglottic laryngeal cancer before and after surgical treatment.

METHODS:

Fourteen patients with advanced supraglottic laryngeal cancer were studied. Cultures of peripheral blood mononuclear cells isolated during the preoperative and late postoperative periods were stimulated with concanavalin A and Bacille Calmette-Guérin, and the supernatant concentrations of interferon-gamma and interleukin-10 were measured.

RESULTS:

For non-stimulated cultures, the interferon-gamma levels produced by the preoperative period and the late postoperative period cultures were lower than the levels produced by the control group cultures. The interferon-gamma levels after stimulation with concanavalin A were higher in the late postoperative period cultures than in the preoperative evaluation cultures. Stimulation with Bacille Calmette-Guérin led to the production of similar levels of interferon-gamma and interleukin-10 by all cultures; thus, stimulation increased the levels of interferon-gamma produced by both the preoperative and postoperative cultures relative to the levels produced by the corresponding unstimulated cultures.

CONCLUSION:

Patients with advanced supraglottic laryngeal cancer exhibit an in vitro deficiency in interferon-gamma secretion by mononuclear cells. Stimulated cells seem to recover this function during the postoperative period.  相似文献   

15.

OBJECTIVE:

Formaldehyde exposure during the menstrual cycle is known to affect the course of allergic lung inflammation. Because our previous data demonstrated that formaldehyde combined with an ovariectomy reduced allergic lung inflammation, we investigated the putative role of ovary removal and progesterone treatment when considering the effect of formaldehyde on allergic lung inflammation.

METHOD:

Ovariectomized rats and their matched controls were exposed to formaldehyde (1%, 3 days, 90 min/day) or vehicle, and immediately after exposure, the rats were sensitized to ovalbumin by a subcutaneous route. After 1 week, the rats received a booster by the same route, and after an additional week, the rats were challenged with ovalbumin (1%) by an aerosol route. The leukocyte numbers, interleukin-10 (IL-10) release, myeloperoxidase activity, vascular permeability, ex vivo tracheal reactivity to methacholine and mast cell degranulation were determined 24 h later.

RESULTS:

Our results showed that previous exposure to formaldehyde in allergic rats decreased lung cell recruitment, tracheal reactivity, myeloperoxidase activity, vascular permeability and mast cell degranulation while increasing IL-10 levels. Ovariectomy only caused an additional reduction in tracheal reactivity without changing the other parameters studied. Progesterone treatment reversed the effects of formaldehyde exposure on ex vivo tracheal reactivity, cell influx into the lungs and mast cell degranulation.

CONCLUSION:

In conclusion, our study revealed that formaldehyde and ovariectomy downregulated allergic lung inflammation by IL-10 release and mast cell degranulation. Progesterone treatment increased eosinophil recruitment and mast cell degranulation, which in turn may be responsible for tracheal hyperreactivity and allergic lung inflammation.  相似文献   

16.

Background

Drug-metabolizing enzymes (DMEs) inhibition based drug-drug interaction and herb-drug interaction severely challenge the R&D process of drugs or herbal ingredients.

Objective

To evaluate the inhibition potential of wogonin (an important flavonoid isolated from the root of Scutellaria baicalensis) towards one of the most important phase II DMEs, UDP-glucuronosyltransferase (UGT) 1A9.

Methods

Both recombinant UGT1A9-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction and human liver microsomes (HLMs)-catalyzed propofol glucuronidation reaction were used as two different probe reactions.

Results

Wogonin noncompetitively inhibited recombinant UGT1A9-catalyzed 4-MU glucuronidation, and exerted competitive inhibition towards HLMs-catalyzed propofol glucuronidation. The inhibition kinetic parameters (Ki) were calculated to be 3.2 µM and 52.0µM, respectively.

Conclusion

Necessary monitoring was needed when wogonin was co-administered with the clinical drugs mainly undergoing UGT1A9-mediated glucuronidation elimination. Additionally, probe reactions-dependent inhibition of wogonin towards the activity of UGT1A9 should be paid attention when translating these in vitro data into in vivo situation.  相似文献   

17.

Study Objective:

The present study aimed to analyze season of birth effects on preferred sleep-wake cycle timing as assessed by Morningness-Eveningness Questionnaire (MEQ).

Participants and Measurements:

The MEQ was administered to a sample of 5,720 university students (3,851 Italians and 1,869 Spaniards; 3,877 female and 1,843 male; mean age 22.23 ± 2.98 years).

Results:

Females preferred to go to bed significantly earlier and sleep longer than males, regardless of season of birth and nationality. Subjects born in spring and summer went to bed and reached midpoint of sleep later than subjects born in fall and winter. Nationality significantly affected all the sleep parameters considered except duration.

Conclusion:

Overall, the effect of the season of birth on sleep preference timing was significant but quantitatively small. We suggest an evolutionary context for the different contributions of genetic and environmental factors in modulating sleep-wake cycles in humans.

Citation:

Natale V; Adan A; Fabbri M. Season of birth, gender, and social-cultural effects on sleep timing preferences in humans. SLEEP 2009;32(3):423–426.  相似文献   

18.

Background

Zoonoses pose a risk to public health.

Objective

To carry out the investigation of the prevalence of gastrointestinal parasites of baboons, Papio anubis, frequenting the Wikki base Camp in Yankari National Park, Nigeria

Method

Formol-ether concentration technique was used to isolate parasite eggs and cysts from faecal samples.

Results

Parasites recovered were Ascaris lumbricoides, Ancylostoma duodenale, Strongyloides stercoralis, Fasciola sp, Schistosoma mansoni, Hymenolepis nana, and Trichostrongylus sp, and cysts of protozoan parasites Entomoeba histolytica, E. coli, and Iodamoeba butschii.

Conclusion

Most of the parasites identified are known to have high pathologic involvement in humans, implicating the baboons as potential source and reservoirs for human zoonotic parasitic infections although further molecular work would be necessary to ascertain if these gastrointestinal parasites are the same strains that infect humans  相似文献   

19.

Background:

Although the psychological assessment of potential living kidney donors (PLKD) is part of the recommendations for action for any transplant coordination, there are not many studies that provide data about the importance of selecting donors for improving transplant outcomes. This work aims to raise awareness of potential kidney donors by designing methods for early detection of potential problems after the transplant, as well as by selecting the most suitable donors.

Methods:

This is a study of 25 PLKD drawn from the General University Hospital of Alicante. Participants completed the Millon Clinical Multiaxial Inventory (MCMI-III) for the study of personality characteristics.

Results:

Women scored higher than men in the compulsive personality scale, and individuals with a genetic link with the recipient scored higher on depressive and dependent scales than did those with other relationships (emotional or altruistic).

Conclusions:

Women showed a pattern of significantly more compulsive personality traits (cautious, controlled, perfectionist) within a non-pathological style. Among the PLKD, there were significantly more women, which is contrary to what typically happens with donations from cadavers. Genetically related subjects scored higher on depression than did those that were emotionally related. The personality assessment of candidates for PLKD can help with developing a post-transplant follow-up regimen for an improved quality of life.

  相似文献   

20.

Background:

In Colombia, dengue is an endemic disease and the four serotypes have been reported.

Objective:

To describe the frequency and severity of dengue in an area of the Colombian Caribbean (Department of Cordoba)

Methods:

A retrospective study was conducted. Two data sources were analysed: The database from the Direction of Health in Córdoba, and clinical registers of patients diagnosed with haemorrhagic fevers and fevers of unknown origin in reference hospitals.

Results:

The mean incidence of dengue between 2003-2010 was 36.5 cases/105 inhabitants (CI95%: 34.3-37.5) and adjusted for sub-reporting, could be between 178.5 and 521.6. The mean incidence of severe dengue was 4.7 cases/105 inhabitants (CI95%: 4.3-5.0). Mean mortality rate due to dengue was 0.3 cases/105 inhabitants. The fatality rate was below 1%. The mean total leukocyte count in patients with dengue was 6,181 mm3 (CI95%: 5,973-6,389) and with severe Dengue was 4,729 mm3 (CI95%: 4,220-5,238). The average platelet count in patients with Dengue was 118,793/mm3 (CI95%: 107,255-130,331) and in patients with Severe Dengue 77,655 (CI95%: 59,640-95,670). Both differences were statistically significant (p <0.05). The frequency of laboratories test per patient in patients with Dengue and severe Dengue were different.

Conclusion:

The department of Cordoba is a highly endemic zone of Dengue and severe Dengue in the Colombian Caribbean. Moreover, the results show significant differences between dengue and severe dengue so much in tests as in frequency of use of healthcare services.  相似文献   

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