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51.
AIM:To evaluate the efficacy and mechanism of action of NCB-02,a standardized Curcumin preparation,against 2,4-dinitrochlorobenzene(DNCB)-induced ulcerative colitis in rats.METHODS:Ulcerative colitis was induced in male rats by sensitizing with topical application of DNCB in acetone for 14 d and intra-colonol challenge with DNCB on day 15.A separate group of animals with vehicle treatment in similar fashion served as control group.Colitis rats were divided into different groups and treated with NCB-02 at doses of 25,50 and 100 mg/kg b.wt p.o.for 10 d.Sulfasalazine at a dose of 100 mg/kg b.wt for 10 d served as a reference group.On day 10 after respective assigned treatment,all the animals were euthanized and the length of the colon,weight of entire colon and distal 8 cm of the colon were recorded.The distal part of the colon was immediately observed under a stereomicroscope and the degree of damage was scored.Further distal 8 cm of the colon was subject to the determination of colonic myeloperoxidase(MPO),lipid peroxidation(LPO)and alkaline phosphatase (ALP)activities.A small piece of the sample from distal colon of each animal was fixed in 10% neutral buffered formalin and embedded in paraffin wax and sectioned for immunohistochemical examination of NFκ-B and iNOS expression.RESULTS:NCB-02 showed a dose dependent protection against DNCB-induced alteration in colon length and weight.NCB-02 treatment also showed a dose dependent protection against the elevated levels of MPO,LPO and ALP,induced by DNCB.NCB-02 demonstrated a significant effect at a dose of 100 mg/kg b.wt.,which was almost equipotent to 100 mg/kg b.wt.of sulfasalazine.Treatment with sulfasalazine and curcumin at a dose of 100 mg/kg b.wt.inhibited the DNCB-induced overexpression of NFκ-B and iNOS in the colon.CONCLUSION:Curcumin treatment ameliorates colonic damage in DNCB-induced colitic rats,an effect associated with an improvement in intestinal oxidative stress and downregulation of colonic NFκ-B and iNOS expression.  相似文献   
52.
Periago MR 《Lancet》2003,362(9390):1157
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53.
Background Melanoma is a tumour with a very variable progression. Whilst some melanomas grow slowly over many years, others can reach several millimetres in thickness in just a few weeks. Since melanoma is a visible superficial tumour, the information obtained from the clinical interview may be of use to calculate the speed of growth of the melanoma. Objective This study aims to assess the growth rate (GR) of melanomas and the association of this GR with various clinical and pathological factors and their usefulness as prognostic markers for localized invasive cutaneous melanomas. Methods The GR of melanomas was calculated as the ratio of tumour thickness to time of development, as obtained from the clinical history (in millimetres per month). Results Applying the GR calculation to patients with a localized melanoma showed a significant association between melanomas with a GR greater than 0.4 mm per month and an age of 65 years or over, male sex, nodular melanoma, tumour thickness, level of invasion, the presence of ulceration and a high mitotic index. As an independent prognostic factor for overall survival, the GR proved to be significant (P = 0.024). Conclusion The GR of localized cutaneous melanomas may be a possible prognostic factor for survival. Additionally, rapid GR is associated with male patients more advanced in age at diagnosis, which suggests the need to assess new strategies for the early detection of these melanomas.  相似文献   
54.
Measurements of oxygen consumption (VO2) were made during sleep in 10 patients with atopic dermatitis. Two groups of healthy children acted as controls. All subjects were studied in bed in an environmental temperature of 24-26 degrees C, and sleep was confirmed during continuous electroencephalographic monitoring. Mean (SD) values of VO2 in sleeping patients who were not scratching ranged from 4.0 (0.4) to 7.4 (0.7), which was not statistically significantly different from control values which ranged from 3.24 (0.3) to 5.56 (0.4). During scratching (while asleep), which occurred in nine out of 10 patients with atopic dermatitis, the mean values of VO2 ranged from 4.5 (0.04) to 10.4 (2.7), and this was significantly higher than the non-scratching patients and the control values. Scratching during sleep in children with atopic dermatitis is associated with increased VO2.  相似文献   
55.

Purpose

We compared the effects of consumption of n-3 polyunsaturated fatty acids (PUFA)-enriched tomato juice versus plain tomato juice on the serum lipid profile and levels of biomarkers related to antioxidant status and cardiovascular disease (CVD) risk in women.

Methods

Eighteen healthy women participated in a 2-week intervention trial involving the daily intake of 500?mL of n-3 PUFA-enriched juice (n?=?11) or plain tomato juice (n?=?7). Each serving of enriched juice provided 250?mg of eicosapentaenoic acid (EPA) plus docosahexanoic acid (DHA). Both juices provided natural antioxidant compounds such as phenolics (181?mg) and lycopene (26.5?mg).

Results

Intervention with the enriched juice had no effect on the lipid profile, and serum levels of triglycerides and cholesterol (total, LDL, and HDL) remained unchanged. The serum antioxidant status improved following juice intake, as revealed by an increase in total antioxidant capacity and a slight decrease in lipid peroxidation. The serum levels of homocysteine, a cardiovascular risk factor, decreased following n-3 PUFA-enriched juice consumption. A decrease in vascular adhesion molecule 1 (VCAM-1) levels was also noted after intake of either plain or enriched tomato juice, whereas intercellular adhesion molecule 1 (ICAM-1) levels only decreased following intake of the enriched juice.

Conclusions

Overall, stronger positive amelioration of CVD risk factors was observed following the intake of n-3 PUFA-enriched juice than after plain tomato juice consumption, which suggested a possible synergistic action between n-3 PUFAs and tomato antioxidants.  相似文献   
56.
Organization, expression and polymorphism of the human persyn gene   总被引:13,自引:0,他引:13  
Persyn is a recently identified member of the synuclein family with a distinct pattern of expression during pre- and postnatal development of the mouse peripheral and central nervous systems. As with other synucleins, persyn is believed to be involved in the pathogenesis of human neurodegenerative diseases. However, in contrast to other synucleins, high levels of persyn mRNA expression were also found in advanced breast carcinomas, suggesting an involvement of the encoded protein in breast tumour progression. Here we have used an antibody specific to human persyn to demonstrate that the level of this protein is increased in ageing cerebral cortex and in breast tumours. We cloned, characterized and sequenced the human persyn genomic locus and localized it to the long arm of chromosome 10 in the q23.2-q23.3 region. Sequence information was used to search for specific mutations in the protein coding regions of persyn mRNA and the persyn gene in breast tumours and tumour cell lines. No tumour-specific mutations were found, but two linked polymorphisms in the coding region were detected, both in mRNA and exons III and IV of the gene. These results suggest that development of breast tumours correlates with overexpression of the wild-type persyn protein. Detailed characterization of the human persyn locus is important for further studies of the involvement of persyn in neurodegeneration and malignancy.   相似文献   
57.
Almaguer‐Mederosa LE, Falcón NS, Almira YR, Zaldivar YG, Almarales DC, Góngora EM, Herrera MP, Batallán KE, Armiñán RR, Manresa MV, Cruz GS, Laffita‐Mesa J, Cyuz TM, Chang V, Auburger G, Gispert S, Pérez LV. Estimation of the age at onset in spinocerebellar ataxia type 2 Cuban patients by survival analysis. Previous studies have investigated the close association that exists between CAG repeat number and the age at onset in SCA2 = spinocerebellar ataxia type 2. These studies have focused on affected individuals. To further characterize this association and estimate the risk of a carrier developing SCA2 at a particular age as a function of a specific CAG repeat size, we have analyzed a large group of 924 individuals, including 394 presymptomatic and 530 affected individuals with a CAG repeat length of 32–79 units. Using a Kaplan–Meier survival analysis, we obtained cumulative probability curves for disease manifestation at a particular age for each CAG repeat length in the 34–45 range. These curves were significantly different (p < 0.001) and showed small overlap. All these information may be very valuable in predictive‐testing programs, in the planning of studies for the identification of other genetic and environmental factors as modifiers of age at onset, and in the design of clinical trials for people at enlarged risk for SCA2.  相似文献   
58.
59.
It has been reported that chloroform administered to BDF1 mice by inhalation for 2 years at concentrations of 5, 30 or 90 p.p.m. for 6 h/day, 5 days/week induced an increase in renal cell tumors in male but not female mice exposed to the doses of 30 and 90 p.p.m. A small increase in liver tumors was statistically significant in the female mice at 90 p.p.m. if the incidences of carcinomas and adenomas were combined. Because chloroform is not a DNA reactive mutagen, a 13-week time-course and dose-response study was conducted under conditions of the original bioassay to examine whether regenerative cell proliferation was an underlying mechanism of carcinogenesis. Mice were given bromodeoxyuridine via infusion during the last 3.5 days prior to necropsy to label cells in S-phase. Chloroform induced pathology and regenerative cell proliferation, measured as the labeling index (LI, percentage of cells in S-phase), were assessed microscopically and immunohistochemically. Male mice exposed to 30 and 90 p.p.m. exhibited a dose-dependent increase in regenerating tubules within the renal cortex and up to a 31-fold increase in LI. No renal lesions or increased LI were observed in females. Increased centrilobular to midzonal hepatocyte degeneration and vacuolation and a 7-fold increase over controls in the hepatocyte LI were observed in the female mice at 90 p.p.m. at 13 weeks. Males exhibited similar pathology, but the increase in LI was not sustained. The observed correlations between cytolethality and regenerative cell proliferation with tumor formation supports extensive evidence that chloroform induces cancer via a non- genotoxic-cytotoxic mode of action. A concentration of 5 p.p.m. is the no-observed-adverse-effect level for nephrotoxicity, cell proliferation and cancer. An appropriate safety factor applied to this value is a straightforward approach to cancer risk assessment that is consistent with the mode of action of chloroform.   相似文献   
60.
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