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1.
The genetic background of cutaneous malignant melanoma (CMM) includes both germ line aberrations in high‐penetrance genes, like CDKN2A, and allelic variation in low‐penetrance genes like the melanocortin‐1 receptor gene, MC1R. Red‐hair colour associated MC1R alleles (RHC) have been associated with red hair, fair skin and risk of CMM. We investigated MC1R and CDKN2A variation in relation to phenotype, clinical factors and CMM risk in the Swedish population. The study cohort consisted of sporadic primary melanoma patients, familial melanoma patients and a control group. An allele‐dose dependent increase in melanoma risk for carriers of variant MC1R alleles (after adjusting for phenotype), with an elevated risk among familial CMM patients, was observed. This elevated risk was found to be significantly associated with an increased frequency of dysplastic nevi (DN) among familial patients compared to sporadic patients. MC1R variation was found to be less frequent among acral lentiginous melanomas (ALM) and dependent on tumour localisation. No association was found between CDKN2A gene variants and general melanoma risk. Two new variants in the POMC gene were identified in red haired individuals without RHC alleles.  相似文献   

2.
Sun exposure is causal for melanoma but is subject to bias of recall so that it is difficult to dissect the role of particular patterns of sun exposure. In this hospital-based case-control study (n = 1991), we aimed to analyze pigmentation traits and signs of actinic damage at different anatomic locations as markers of melanoma risk in central European patients. Although all signs of actinic damage (freckling, wrinkling and solar lentigos) were significantly associated with melanoma risk in multivariate logistic regression models adjusting for age and sex, the strongest associations were observed for the dorsal parts of the body: adjusted odds ratios [OR] were 4.22 for wrinkling on the neck, 3.43 for solar lentigos and 3.37 for freckling on the back (all P < 0.001), respectively. These associations were independent of age, sex and pigmentation traits. Our results indicate that signs of actinic damage are predictors of melanoma risk, particularly on the back.  相似文献   

3.
Melanoma growth stimulatory activity (MGSA) is an acid and heat stable, auto-stimulatory growth factor which was first isolated from culture medium conditioned by the Hs294T human melanoma cell line. In this report, we describe the purification of MGSA from acid ethanol extracts of Hs294T tumors grown in nude mice using a series of Bio-Gel P30, reverse phase-high performance liquid chromatography and heparin-sepharose steps. This modified procedure provides a 10-fold improved yield of MGSA over previously published procedures. Purified MGSA-stimulated melanoma cell growth in both 3H-thymidine and cell number assays over a concentration range of 0.06 to 6 ng/ml. The MGSA bioactivity was primarily associated with fractions which exhibited molecular weights of 16 and 13-14 Kd based upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Purified platelet-derived growth factor (PDGF), insulin-like growth factor (IGF-1), transforming growth factor-beta (TGF beta), and epidermal growth factor (EGF) in combination with TGF beta did not stimulate 3H-thymidine incorporation in Hs294T cells under the conditions used for MGSA bioassay. Monoclonal antibody to MGSA was used to screen melanoma and benign nevus cultures as well as fixed sectioned tissue for MGSA. The majority of the melanoma cultures were MGSA positive, while most nevus cultures were MGSA negative. However, when fixed sectioned tissue was screened for MGSA immunoreactivity, melanoma tissue was MGSA positive and three-fourths of the benign nevi were MGSA positive. In addition, epidermal keratinocytes and several tissues exhibiting proliferative disorders contained immunoreactive MGSA. These data suggest that MGSA may be a normal regulator of growth and that the microenvironment of the cell may regulate both production of MGSA and response to MGSA.  相似文献   

4.
《Cancer epidemiology》2014,38(4):357-363
BackgroundEpidemiological studies on anthropometric features and cutaneous melanoma risk in women yielded inconsistent results, with few analyses involving prospective cohort data. Our objective was to explore several anthropometric characteristics in relation to the risk of melanoma in women.MethodsWe prospectively analysed data from E3N, a French cohort involving 98,995 women born in 1925–1950. Participants completed self-administered questionnaires sent biennially over 1990–2008. Relative risks (RRs) and 95% confidence intervals (CIs) were computed using Cox proportional hazards regression models, adjusted for age, number of naevi, freckling, skin and hair colour, skin sensitivity to sun exposure, residential sun exposure, and physical activity.ResultsHeight was positively associated with melanoma in age-adjusted models only (RR = 1.27, 95% CI = 1.05–1.55 for ≥164 cm vs. <160 cm; P for trend = 0.02). After full adjustment, there was a significantly positive relationship between sitting-to-standing height ratio and melanoma risk (RR = 1.40, 95% CI = 1.06–1.86 for ≥0.533 vs. <0.518; P for trend = 0.02). A large body shape at menarche was inversely associated with the risk of melanoma (RR = 0.78, 95% CI = 0.62–0.98; compared with lean). However, weight, body mass index, body surface area, waist or hip circumference, sitting height or leg length were not significantly associated with risk.ConclusionThese results suggest that height, sitting-to-standing height ratio and body shape at menarche may be associated with melanoma risk. Further research is required to confirm these relationships and better understand the underlying mechanisms.  相似文献   

5.
Cyclic variations in the incidence of skin malignant melanoma during the years 1964–1985 in East Bohemia (excluding the districts of Pardubice and Svitavy), Czechoslovakia have been studied, as linear correlations with solar activity indexes have been revealed. The following statistical methods were applied: periodogram regression analysis, phase-correlation analysis, sigmamethod and Student'st-test. The discretization of the data is on the basis of 1 year. Different cycles were found in the incidence variations (T=7.5 years,T=11.5 years, etc.), and this has been correlated with the variations of two heliophysical indexes (, W) for the same time period. A few significant statistical relationships have been established with a time difference (lag-period) between the extremes of the data series; the incidence maxima follow the peaks of solar activity and appear about the minima of solar indexes, mainly.This paper was presented in part at the IV National Congress of Medical Geography, 1991, Varna, Bulgaria  相似文献   

6.
Antitumor cytotoxicity of NK cells and T cells expressing NK-associated receptors is regulated by interaction between their cell surface killer immunoglobulin-like receptors (KIRs) and CD94/NKG2 heterodimers with MHC class I ligands on target cells. To test the hypothesis that KIR and/or HLA polymorphisms, and KIR/HLA combinations could contribute to the tumorigenesis, association studies were performed in 50 patients with malignant melanoma (MM) in different stages of disease and 54 controls. Our data showed that the frequency of inhibitory and activating KIR genes and KIR genotypes did not differ significantly between healthy individuals and melanoma patients. HLA haplotype distribution showed statistically significant increased frequencies of A*01-B*35-Cw*04 (0.069 vs 0.000; pc<0.05; OR=19.9), A*01-B*08-DRB1*03 (0.079 vs 0.019; pc<0.05; OR=4.5), and A*24-B*40-DRB1*11 (0.026 vs 0.000; pc<0.05; OR=7.1) in melanoma patients compared with healthy controls. Individuals homozygous for group 2 HLA-C ligands were less frequent in the patient group compared with the control cohort (12% vs 31.5%; p<0.017). In addition, we observed an increased frequency (88.0% vs 68.5%; p=0.017; OR=2.80) of KIR2DL2/2DL3 in combination with their group 1 HLA-C ligands, while the presence of these KIRs in the absence of the putative ligands was decreased (12.0% vs 31.5%; p=0.017) in the patient group. Furthermore, an increased frequency of activating KIR2DS1 in the absence of the putative HLA-CLys80 ligands was found in melanoma patients (16.0% vs 9.2%). In contrast, KIR2DS2 was absent in patients more often (38.0% vs 25.9%) when the presumptive HLA-CAsn80 ligands were present. A slightly higher incidence of KIR3DL1 in combination with the less effective Bw4Thr80 ligands was seen in patients with primary (20.8%) compared with metastatic (4.2%) disease. The data obtained in this study imply that there may not be a direct association between KIR gene content in the genome and the presence of malignant melanoma, or melanoma progression. However, some HLA haplotypes could be predisposing to MM in the Bulgarian population. Furthermore, distinct KIR/HLA ligand combinations may be relevant to the development of malignancy whereby inhibition overrides activation of NK cells and T cells expressing NK-associated receptors, which in turn might facilitate tumor escape and progression.  相似文献   

7.
The development and progression of melanoma have been attributed to independent or combined genetic and epigenetic events. There has been remarkable progress in understanding melanoma pathogenesis in terms of genetic alterations. However, recent studies have revealed a complex involvement of epigenetic mechanisms in the regulation of gene expression, including methylation, chromatin modification and remodeling, and the diverse activities of non-coding RNAs. The roles of gene methylation and miRNAs have been relatively well studied in melanoma, but other studies have shown that changes in chromatin status and in the differential expression of long non-coding RNAs can lead to altered regulation of key genes. Taken together, they affect the functioning of signaling pathways that influence each other, intersect, and form networks in which local perturbations disturb the activity of the whole system. Here, we focus on how epigenetic events intertwine with these pathways and contribute to the molecular pathogenesis of melanoma.  相似文献   

8.
Yoshikuni Hodoki 《Hydrobiologia》2005,534(1-3):193-204
The effects of solar ultraviolet radiation (UVR) on the development of a periphyton community were studied in an outdoor artificial stream apparatus. Algal biomass, species composition, and bacterial cell density were measured under full sunlight and non-UVR (photosynthetically active radiation [PAR]-only) conditions. Attachment of algae was detected on days 6–9. Although the chlorophyll-a concentration under non-UVR conditions was 2–4 times that under full sunlight (PAR + UVR) throughout the experiment, neither net algal growth rate nor species composition differed significantly between the two light conditions. The relative carotenoid pigment contents of attached algae in the PAR + UVR condition were 1.1–1.3 times those in the non-UVR condition. Rates of increase of bacterial cell densities under the PAR + UVR condition were depressed by solar UVR for the first few days, although there were no apparent differences in the rates of increase between the light conditions later in the experiment. The small effect of UVR on the development of this periphyton community may be attributable to low UV flux at this study site and to the experimental conditions under which the algae were kept: a high physiological state with high nutrient conditions. Attached bacteria and algae that colonize substrata first are likely to be sensitive to solar UVR, and the negative effects of UVR are mitigated by the development of a periphyton community.  相似文献   

9.

Objectives

Radiotherapy in patients with sinonasal mucosal melanoma (SNMM) was given as alternative treatment to surgery in cases with advanced, inoperable tumors or those not eligible for surgery. We presented the outcomes for patients with SNMM treated with radiotherapy alone.

Material and methods

The retrospective review of 6 consecutive SNMM (nasal cavity – 4 pts. and paranasal sinus – 2 pts.) patients (3 males and 3 females at mean age 64 years) treated between 2008 and 2016 was presented. The stage of disease was: T3 (1 pt.), T4a (3 pts.), T4b (2 pts.); with N0 and M0 in all patients. All patients underwent definitive primary photon radiotherapy (IMRT) alone; dose 66–72?Gy was delivered in 22–24 fractions given in 5 fractions (3?Gy) a week.

Results

The complete remission was observed in all our patients but only one patient survived 5 years without disease. Five patients died due to multiple distant metastases; two of those patients developed associated local recurrence 7–8 months after radiotherapy.

Conclusion

SNMM has a poor prognosis due to its high metastatic potential. Based on our numerically small report and data from literature we concluded that primary radiotherapy alone assured complete remission and even 5-year disease-free survival in only a few individual patients.  相似文献   

10.
Ultraviolet radiation (UVR) is a naturally occurring stressor to most forms of life. The sole relevant source of this stressor is the sun. The Earth's stratospheric ozone layer reduces the amount of UVR that reaches the Earth's surface. The potential for continued depletion of this ozone layer and environmental changes that increase the penetrance of aquatic habitat, both due to human activities, and the subsequent increase in UVR are global environmental concerns for both humans and ecosystems. An integrated risk assessment provides efficiency in data gathering, analysis and reporting by enabling risk assessors to use the combined knowledge from many disciplines to evaluate overall risk. This report describes the steps and example information that could be used for an integrated risk assessment but is not an actual risk assessment with all its associated calculations and conclusions. It is intended to illustrate the advantages of the integrated risk assessment approach for evaluating adverse effects of a nonchemical stressor.  相似文献   

11.
Metastatic melanoma remains one of the most lethal and poorly treated forms of human cancer. Its incidence is on the rise, but no therapies offering improved survival rates have been developed over the last 40 years. This has changed with the recent Food and Drug Administration (FDA) approval of the CTLA-4 function blocking antibody Ipilimumab (Yervoy), proven to extend life in patients with previously treated or untreated metastatic melanoma [39,40]. CTLA-4 is a receptor that normally functions to inhibit inappropriate or prolonged activation of T-cells. This review presents the history of initial research into the function of the CTLA-4 receptor, the pre-clinical evidence for CTLA-4 blockade's utility in cancer treatment, and the recent human clinical trials that have proven its efficacy in advanced stage melanoma. Ipilimumab represents one of a growing class of cancer immunotherapies currently under development and highlights both the promise and relative infancy of these agents in the clinical setting.  相似文献   

12.
Cover plus: ways of measuring plant canopies and the terms used for them   总被引:1,自引:0,他引:1  
Aim: To clarify the concepts and terms that have been used in recording plant canopies and the methods used for measuring them. Concepts: The concepts considered are cover, top cover, repeated cover, number of layers, proportion of repeated cover and leaf area index (LAI). Variants include canopy cover, basal area and leaf area density. Other terms have been used in the past, some are now ambiguous and some are counter‐intuitive. Measurement: Cover and its related concepts can be measured by point intercept, line intercept, angle sampling, charting and image analysis, canopy transmittance, complete enumeration, clipping and allometry. The common procedure of adding the cover of individual species to calculate a “total cover” is invalid: a nonsense number is produced. Other measures of abundance: Cover‐abundance, density, frequency, biomass and calorific values can also be used to measure abundance. They are related to cover. Especially, shoot frequency at a point is cover (the point intercept method). Subjective estimates: There are severe problems with cover‐abundance scales, such as that of Braun‐Blanquet. Estimation of abundance “by eye”, by “informed guess”, etc. has too often compromised results in vegetation science.  相似文献   

13.
The responsiveness of Mendelian diseases to an increase in the mutation rate is studied by using the concept of the mutation component (MC) of genetic diseases. Algebraic expressions to evaluate MC at any specific generation following either a one-time or a permanent increase in mutation rate are derived and are illustrated with numerical examples. For a one-time increase in mutation rate, the analysis shows that the first generation MC for autosomal dominant diseases is equal to the selection coefficient; this is also true for X-linked diseases (adjusted for the proportion of X-chromosomes in males). For autosomal recessive diseases the first generation MC is substantially smaller than that for autosomal dominants. In subsequent generations MC gradually decays to zero. Under conditions of a permanent increase in the mutation rate, the MC for autosomal dominant, X-linked and completely recessive autosomal disorders progressively increases to reach a value of one at the new equilibrium. For incompletely recessive autosomal disorders, however, the MC at equilibrium can be larger than one. The rates of approach to the new equilibrium are different for the different classes of diseases, dictated by selection and time (in generations) following radiation exposure. The effects of increases in mutation rate on MC are more pronounced for autosomal dominants, followed by X-linked and are far less for autosomal recessives. Even for autosomal dominants, the early generation effects of radiation exposures would not be appreciable unless the heterozygotes have a severely reduced fitness.  相似文献   

14.
A 56-year-old man with BRAFV600E melanoma and spinal metastases treated with vemurafenib and stereotactic radiation showed a partial response without neurological, skin or mucosal toxicity, 8 months after completion of this combination. This case suggests that stereotactic radiation spares normal tissues and might be safer than conventional fractionated radiation with vemurafenib.  相似文献   

15.
The amount, chemical composition, and source of dissolved organic carbon (DOC), together with in situ ultraviolet (UV-B) attenuation, were measured at 1–2 week intervals throughout the summers of 1999, 2000, and 2001 at four sites in Rocky Mountain National Park (Colorado). Eight additional sites, four in Sequoia and Kings Canyon National Park/John Muir Wilderness (California) and four in Glacier National Park (Montana), were sampled during the summer of 2000. Attenuation of UV-B was significantly related to DOC concentrations over the three years in Rocky Mountain (R2 = 0.39, F = 25.71, P < 0.0001) and across all parks in 2000 (R2 = 0.44, F = 38.25, P < 0.0001). The relatively low R2 values, however, reflect significant temporal and spatial variability in the specific attenuation per unit DOC. Fluorescence analysis of the fulvic acid DOC fraction (roughly 600–2,000 Daltons) indicated that the source of DOC significantly affected the attenuation of UV-B. Sites in Sequoia–Kings Canyon were characterized by DOC derived primarily from algal sources and showed much deeper UV-B penetration, whereas sites in Glacier and Rocky Mountain contained a mix of algal and terrestrial DOC-dominated sites, with more terrestrially dominated sites characterized by greater UV-B attenuation per unit DOC. In general, site characteristics that promoted the accumulation of terrestrially derived DOC showed greater attenuation of UV-B per unit DOC; however, catchment vegetation and soil characteristics, precipitation, and local hydrology interacted to make it difficult to predict potential exposure from DOC concentrations.  相似文献   

16.

Introduction  

Raw spectral data from matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) with MS profiling techniques usually contains complex information not readily providing biological insight into disease. The association of identified features within raw data to a known peptide is extremely difficult. Data preprocessing to remove uncertainty characteristics in the data is normally required before performing any further analysis. This study proposes an alternative yet simple solution to preprocess raw MALDI-TOF-MS data for identification of candidate marker ions. Two in-house MALDI-TOF-MS data sets from two different sample sources (melanoma serum and cord blood plasma) are used in our study.  相似文献   

17.

Objectives

To investigate which anthropometric adiposity measure has the strongest association with cardiovascular disease (CVD) risk factors in Caucasian men and women without a history of CVD.

Design

Systematic review and meta-analysis.

Methods

We searched databases for studies reporting correlations between anthropometric adiposity measures and CVD risk factors in Caucasian subjects without a history of CVD. Body mass index (BMI), waist circumference, waist-to-hip ratio, waist-to-height ratio and body fat percentage were considered the anthropometric adiposity measures. Primary CVD risk factors were: systolic blood pressure, diastolic blood pressure, high density lipoprotein (HDL) cholesterol, triglycerides and fasting glucose. Two independent reviewers performed abstract, full text and data selection.

Results

Twenty articles were included describing 21,618 males and 24,139 females. Waist circumference had the strongest correlation with all CVD risk factors for both men and women, except for HDL and LDL in men. When comparing BMI with waist circumference, the latter showed significantly better correlations to CVD risk factors, except for diastolic blood pressure in women and HDL and total cholesterol in men.

Conclusions

We recommend the use of waist circumference in clinical and research studies above other anthropometric adiposity measures, especially compared with BMI, when evaluating CVD risk factors.  相似文献   

18.
AIM: To evaluate the microbial contamination of 91 cosmetics (23 o/w emulsions, 47 tensiolytes, 21 aqueous pastes) in three different states of use (intact, in-use, ending product) and the protection efficacy of the preservative systems most frequently used in the analysed cosmetic formulations. METHODS AND RESULTS: Total bacterial count, isolation and identification of pathogenic isolates were performed on the collected cosmetics. About 10.6% of tensiolytes (13.5% bath foam, 6.7% shampoo, 10% liquid soaps) were contaminated by Staphylococcus warneri, Staphylococcus epidermidis and Pseudomonas putida. The efficacy of the preservative systems of two cosmetic products, tested against standard micro-organisms (Staphylococcus aureus ATCC 4338 and Pseudomonas aeruginosa ATCC 9027) and two isolates from cosmetics in this study (S. epidermidis and P. putida), satisfied the Cosmetics, Toiletries, and Fragrance Association and Official Italian Pharmacopeia criteria, while only one tested cosmetic respected the Rapid Challenge Test criterion. CONCLUSIONS: Contaminated cosmetic products are relatively uncommon, but some products, unable to suppress the growth of several micro-organisms, represent a potential health hazard. SIGNIFICANCE AND IMPACT OF THE STUDY: The challenge test may be performed not only during the preparation of the preservative system in the intact cosmetics, but also be used to evaluate the protection efficacy during their use.  相似文献   

19.
Heterotrimeric guanine nucleotide-binding proteins (G proteins) mediate many pathways including the beta-adrenergic signaling pathway. The C825T polymorphism in the gene coding for the beta3 subunit of G proteins (GNB3) has been shown to be associated with several phenotypes such as hypertension, obesity, and diabetes mellitus comprising the metabolic syndrome. The GNB3 C825T polymorphism may therefore be associated with many atherosclerosis-related phenotypes. On these grounds, we studied the C825T polymorphism in relation to atherosclerosis-related phenotypes in a large Japanese population. Analyses in general linear models showed that T carriers had a significantly wider pulse pressure (P=0.0089) as well as a significantly higher systolic blood pressure (P=0.026). In contrast, analyses in logistic regression models showed that the C825T polymorphism was not significantly associated with each of the four major classical risk factors for cardiovascular and cerebrovascular disease (obesity, hypertension, hypertriglyceridemia, and diabetes mellitus). However, a significantly higher percentage of subjects had none of the four disorders in CC homozygotes than in T carriers (P=0.026). Thus, the C825T polymorphism was significantly associated with clustering of these four risk factors. Although the effect of the gene on each phenotype appears to be weak, considering the combined impact of the effects of the C825T polymorphism on risk factors, the GNB3 gene may be an important gene for human health.  相似文献   

20.
Dopaminergic and glutamatergic dysfunction is believed to play a central role in the pathophysiology of schizophrenia. However, it is unclear if abnormalities predate the onset of schizophrenia in individuals at high clinical or genetic risk for the disorder. We systematically reviewed and meta‐analyzed studies that have used neuroimaging to investigate dopamine and glutamate function in individuals at increased clinical or genetic risk for psychosis. EMBASE, PsycINFO and Medline were searched form January 1, 1960 to November 26, 2020. Inclusion criteria were molecular imaging measures of striatal presynaptic dopaminergic function, striatal dopamine receptor availability, or glutamate function. Separate meta‐analyses were conducted for genetic high‐risk and clinical high‐risk individuals. We calculated standardized mean differences between high‐risk individuals and controls, and investigated whether the variability of these measures differed between the two groups. Forty‐eight eligible studies were identified, including 1,288 high‐risk individuals and 1,187 controls. Genetic high‐risk individuals showed evidence of increased thalamic glutamate + glutamine (Glx) concentrations (Hedges’ g=0.36, 95% CI: 0.12‐0.61, p=0.003). There were no significant differences between high‐risk individuals and controls in striatal presynaptic dopaminergic function, striatal D2/D3 receptor availability, prefrontal cortex glutamate or Glx, hippocampal glutamate or Glx, or basal ganglia Glx. In the meta‐analysis of variability, genetic high‐risk individuals showed reduced variability of striatal D2/D3 receptor availability compared to controls (log coefficient of variation ratio, CVR=–0.24, 95% CI: –0.46 to –0.02, p=0.03). Meta‐regressions of publication year against effect size demonstrated that the magnitude of differences between clinical high‐risk individuals and controls in presynaptic dopaminergic function has decreased over time (estimate=–0.06, 95% CI: –0.11 to –0.007, p=0.025). Thus, other than thalamic glutamate concentrations, no neurochemical measures were significantly different between individuals at risk for psychosis and controls. There was also no evidence of increased variability of dopamine or glutamate measures in high‐risk individuals compared to controls. Significant heterogeneity, however, exists between studies, which does not allow to rule out the existence of clinically meaningful differences.  相似文献   

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