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11.
Summary We have developed an in vitro system to examine the influence of adipocytes, a major mammary stromal cell type, on the growth of a murine mammary carcinoma, SP1. Previously, we have shown that 3T3-L1 adipocytes release a mitogenic factor, hepatocyte growth factor, which strongly stimulates proliferation of SP1 cells. We now show that 3T3-L1 pre-adipocytes secrete active inhibitory molecules which inhibit DNA synthesis in SP1 cells. In addition, latent inhibitory activity is present in conditioned media (CM) from both pre-adipocytes and adipocytes, and is activated following acid treatment. CM also inhibited DNA synthesis in Mv1Lu wild type epithelial cells, but not DR27 mutant epithelial cells which lack TGF-β type II receptor. Inhibitory activity of CMs was partially abrogated by neutralizing anti-TGF-β1 and anti-TGF-β2 antibodies, and was removed following ultrafiltration through membranes of 10 000 Mr but not 30 000 Mr pore size. These results show that the inhibitory effect on DNA synthesis is mediated by TGF-β1-like and TGF-β2-like molecules. In addition, acid-treated CM as well as purified TGF-β inhibited differentiation of pre-adipocytes. Untreated pre-adipocyte CM, but not mature adipocyte CM, spontaneously inhibited adipocyte differentiation. Together, these findings indicate that pre-adipocytes spontaneously activate their own secreted TGF-β, whereas mature adipocytes do not, and suggest that activation of TGF-β has a potent negative regulatory effect on adipocyte differentiation and tumor growth. Thus, TGF-β may be an important modulator of tumor growth and adipocyte differentiation via both paracrine and autocrine mechanisms. These findings emphasize the importance of adipocyte-tumor interactions in the regulation of tumor microenvironment.  相似文献   
12.
The type and frequency of structural hemoglobin variants and their hematological and molecular characteristics were identified using PCR-RFLP and sequencing techniques in 66 individuals from 33 unrelated families who referred to the two clinics of Kermanshah University of Medical Sciences from 2005 to 2006. We detected 28 subjects carrier for Hb D-Punjab (42.4%), 21 individuals carrier of Hb Q-Iran (31.8%), 12 subjects heterozygous for Hb Setif (18.2%), four cases with sickle cell disease (6.1%), and one case with Hb C (1.5%). All βS genes (4 genes) were linked to the Benin haplotype with negative Taq I site 5′ to γA gene. All βD-Punjab genes (29 genes) were in linkage disequilibrium with haplotype I. The only βC chromosome was linked to haplotype II. Both β0-thalassemia chromosomes with CD15 (G → A) mutation had haplotype background I. Three β+-thalassemia chromosomes with IVSI.110 (G → A) mutation were associated with haplotype I [+ − − − − + +]. In turn, the three β-thalassemia chromosomes with IVS II.1 G → A mutation were associated with atypical haplotype [− + + + + + −]. Hematological indices of carriers of Hb D-Punjab, Hb Q-Iran and Hb Setif were lower than those reported for normal individuals. For the first time, we have reported the haplotype background of βS gene among Kurdish population of Iran. Our results revealed that Hb D-Punjab is the most prevalent β-globin chain structural variant in this area and that is followed in frequency by an α-chain variant, Hb Q-Iran. The result of present study is useful for clinical management and the establishment of screening programmes in Western Iran.  相似文献   
13.
A new one-step liquid chromatography–electrospray tandem MS/MS method is described to quantify ezetimibe (EZM) a novel lipid lowering drug in human serum. Also using collision-induced dissociation (CID) of the analyte, identification and chromatographic separation of its major metabolite, ezetimibe glucuronide (EZM-G) is achieved in this study. A thawed serum aliquot of 100 μL was deproteinated by addition of 500 μL methanol containing omeprazole as internal standard (I.S.). Separation of the drug, its metabolite and the I.S. were achieved using acetonitrile–water (70:30, v/v) as mobile phase at flow rate of 0.5 mL/min on a MZ PerfectSil target C18 column. Multiple reaction monitoring (MRM) mode of precursor–product ion transition (408.7 → 272.0 for EZM and 345 → 194.5 for the I.S.) was applied for detection and quantification of the drug while, EZM-G was chromatographically separated and identified using CID. The analytical method was linear over the concentration range of 1–32 ng/mL of EZM in human serum with a limit of quantification of 1 ng/mL. The coefficient variation values of both inter- and intra-day analysis were less than 8% whereas the percentage error was less than 3.7. The validated method was applied in a randomized cross-over bioequivalence study of two different EZM preparations in 24 healthy volunteers.  相似文献   
14.
TGF-beta signaling: a tale of two responses   总被引:10,自引:0,他引:10  
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15.
The kinetics of microperoxidase-11 (MP-11) in the oxidation reaction of guaiacol (AH) by hydrogen peroxide was studied, taking into account the inactivation of enzyme during reaction by its suicide substrate, H2O2. Concentrations of substrates were so selected that: 1) the reaction was first-order in relation to benign substrate, AH and 2) high ratio of suicide substrate to the benign substrate, [H2O2] > [AH]. Validation and reliability of the obtained kinetic equations were evaluated in various nonlinear and linear forms. Fitting of experimental data into the obtained integrated equation showed a close match between the kinetic model and the experimental results. Indeed, a similar mechanism to horseradish peroxidase was found for the suicide-peroxide inactivation of MP-11. Kinetic parameters of inactivation including the intact activity of MP-11, alphai, and the apparent inactivation rate constant, ki, were obtained as 0.282 +/- 0.006 min(-1) and 0.497 +/- 0.013(-1) min at [H2O2] = 1.0 mM, 27 degrees C, phosphate buffer 5.0 mM, pH = 7.0. Results showed that inactivation of microperoxidase as a peroxidase model enzyme can occur even at low concentrations of hydrogen peroxide (0.4 mM).  相似文献   
16.

Background

The incidence of Hypertension as a major cardiovascular threat is increasing. The best known diet for hypertensives is 'no added salt diet'. In this study we evaluated the effect of 'no added salt diet' on a hypertensive population with high dietary sodium intake by measuring 24 hour urinary sodium excretion.

Methods

In this single center randomized study 80 patients (60 cases and 20 controls) not on any drug therapy for hypertension with mild to moderate hypertension were enrolled. 24 hour holter monitoring of BP and 24 hour urinary sodium excretion were measured before and after 6 weeks of 'no added salt diet'.

Results

There was no statistically significant difference between age, weight, sex, Hyperlipidemia, family history of hypertension, mean systolic and diastolic BP during the day and at night and mean urinary sodium excretion in 24 hour urine of case and control groups. Seventy eight percent of all patients had moderate to high salt intake. After 6 week of 'no added salt diet' systolic and diastolic BP significantly decreased during the day (mean decrease: 12.1/6.8 mmhg) and at night (mean decrease: 11.1/5.9 mmhg) which is statistically significant in comparison to control group (P 0.001 and 0.01). Urinary sodium excretion of 24 hour urine decreased by 37.1 meq/d ± 39,67 mg/dl in case group which is statistically significant in comparison to control group (p: 0.001). Only 36% of the patients, after no added salt diet, reached the pretreatment goal of 24 hour urinary sodium excretion of below 100 meq/dl (P:0.001).

Conclusion

Despite modest effect on dietary sodium restriction, no added salt diet significantly decreased systolic and diastolic BP and so it should be advised to every hypertensive patient.

Trial Registration

Clinicaltrial.govnumber NCT00491881  相似文献   
17.

The aim of this study is to investigate the effect of stress modulators on vegetative growth, antioxidants, and nutrient content of Thymus vulgaris L. under water deficit stress conditions. A factorial experiment was performed in the form of a randomized complete block design with 10 treatments and 3 replications in the 2019–2020 growing season. The factors were stress modulators at 5 levels (ZN: zinc nano-fertilizer, AA: amino acid, SW: seaweed, HA: humic acid and C: control) and irrigation regime at 2 levels [FIrr: full irrigation (100% field capacity) and DIrr: deficit irrigation (50% field capacity)]. The highest plant height, number of branches, and total dry weight of the garden thyme plant were observed in the foliar application of HA and SW under full irrigation conditions. Relative water content, chlorophyll a and b, and uptake of nutrients (N, P, and K) were reduced under water deficit stress, but the foliar application of stress modulators increased relative water content, chlorophyll content, and nutrient uptake of the garden thyme plant significantly compared with control. The water deficit increased proline content, total flavonoid, and phenol content in the garden thyme plant. So, the highest total flavonoid and phenol content was obtained from plants treated with HA, whereas proline content was higher in the control plants. Soluble sugars and essential oil increased significantly under water deficit stress conditions. The foliar application of HA compared to the control plant increased soluble sugars and essential oil in garden thymes. The activities of catalase, superoxide dismutase, and ascorbate peroxidase enzymes were improved in stress modulator treatments such as HA and SW compared to control plants under water deficit stress conditions. The plants of garden thymes showed a good response to stress modulator treatments under water stress conditions, and HA and SW treatments were found to be more effective.

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18.
Biodegradation - Biological waste degradation is the main driving factor for landfill emissions. In a 2-year laboratory experiment simulating different landfill in-situ aeration scenarios, the...  相似文献   
19.
Molecular Biology Reports - In this study, the optimized niosomal formulation containing paclitaxel using non-ionic surfactants and cholesterol was designed and its cytotoxic effects against...  相似文献   
20.
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