Multivariate dependence and portfolio optimization algorithms under illiquid market scenarios

We propose a model for optimizing structured portfolios with liquidity-adjusted Value-at-Risk (LVaR) constraints, whereby linear correlations between assets are replaced by the multivariate nonlinear dependence structure based on Dynamic Conditional Correlation t-copula modeling. Our portfolio optimization algorithm minimizes the LVaR function under adverse market circumstances and multiple operational and financial constraints. When we consider a diversified portfolio of international stock and commodity market indices under multiple realistic portfolio optimization scenarios, the obtained results consistently show the superiority of our approach relative to other competing portfolio strategies including the minimum-variance, risk-parity and equally weighted portfolio allocations

Increased homocysteine plasma levels in breast cancer patients of a Mexican population

Aim: Hyperhomocysteinemia has been associated with different pathologies, including cardiovascular diseases, hypertension, diabetes, and breast cancer (BC). To examine the differences in total homocysteine (tHcy) plasma levels, we compared healthy women to BC patients from a Mexican population. Materials and Methods: The tHcy plasma levels were measured using high-performance liquid chromatography with a fluorescence detector in 89 female controls and 261 BC patients. Results: The observed plasma tHcy levels were significantly higher among the BC patients (11.1019 ± 5.9161 µmol/l) compared to the controls (9.1046 ± 1.3213 µmol/l) (p = 0.002), and these differences were evident when stratified by age (≥ 50 years old), menopause status, overweight and obesity, miscarriages, node metastases, progression, subtype classification (luminal, Her2 and triple negative) and nonresponse to chemotherapy. Conclusions: The tHcy plasma levels could be a good marker for the progression and chemosensitivity of BC in the analyzed sample from a Mexican population. Key Words: plasma levels, homocysteine, HPLC, breast cancer, Mexican population

7th Drug hypersensitivity meeting: part two

No abstract availabl

The TP53 16-bp duplication polymorphism is enriched in endometriosis patients

Background/Aim: The TP53 tumor suppressor gene encodes the nuclear phosphoprotein p53, which plays an important role in cell cycle regulation, apoptosis, DNA repair and angiogenesis. The TP53 gene contains common genetic polymorphisms that influence gene activity. Clinical implications of TP53 polymorphisms have been reported for several diseases, including a variety of solid tumors and endometriosis. We evaluated the association of a TP53 duplication polymorphism with endometriosis. Methods: We evaluated the role of the TP53 16-bp duplication polymorphism by comparing the genotypes of 204 healthy women (controls with surgically excluded endometriosis) to the genotypes of 151 women with endometriosis in the Mexican population. Results: The observed genotype frequencies for controls and endometriosis patients were 0.5 and 5% for 16 bp+/+, 11 and 21% for 16 bp+/-, and 88.5 and 77% for 16 bp-/-, respectively. The odds ratio (OR) was 9.8 (95% CI 1.2-446.8; p = 0.01). The association was more evident when we compared the distribution of genotype 16 bp+/+ to genotype 16 bp+/-. In patients with moderate/severe endometriosis, the OR was 4.0 (95% CI 1.6-9.8; p = 0.003). Conclusion: Our data suggest that the 16-bp duplication polymorphism in TP53 contributes significantly to endometriosis susceptibility in the Mexican population. Copyright � 2012 S. Karger AG, Basel

Association of TP53 gene codon 72 polymorphism with endometriosis in Mexican women

The TP53 tumor suppressor gene plays an important role in cell cycle regulation; polymorphisms of this gene have been associated with endometriosis. We examined the role of TP53 codon 72 polymorphism by comparing genotypes of 235 healthy Mexican women (controls with surgically excluded endometriosis) with the genotypes of 151 Mexican women with endometriosis. The observed genotype frequencies for controls and endometriosis patients were 8 and 22% for proline/proline (Pro/Pro), 30 and 34% for proline/arginine (Pro/Arg), and 62 and 44% for arginine/arginine (Arg/Arg), respectively. We found that odds ratio (OR) = 3.3; 95% confidence intervals (95%CI) = 1.7-6.4; P = 0.0001. The association was also evident in the comparison of the distributions of genotypes Pro/Pro and Pro/Arg in patients with moderate-to-severe endometriosis; OR = 1.9; 95%CI = 0.95-3.9; P = 0.049. We suggest that genotype Pro/Pro of codon 72 polymorphism in TP53 contributes significantly to endometriosis susceptibility in the Mexican population. ZapotitlánFUNPEC-RP

CYP1A1 *2B and *4 polymorphisms are associated with lung cancer susceptibility in Mexican patients

Background: CYP1A1 is a gene involved in the high aryl hydrocarbon hydroxylase -inducible phenotype, which is a genetically-determined variation among individuals that has been associated with lung cancer risk. More specifically, CYP1A1*2B and *4 polymorphisms have been associated with high susceptibility to lung cancer among cigarette smokers. Materials and methods: DNA was obtained from blood samples and we studied by PCR-RFLP the distribution of CYP1A1*2B (n=248) and *4 (n=222) polymorphisms in healthy controls and 222 lung cancer patients from a Mexican population. Results: Comparisons between groups showed an increased risk for lung cancer patients of *2B/*2B (18%; OR 7.6; 95% CI 3.0-19.2) and *4/*4 genotypes (15%; OR 11.45; 95% CI 2.19-59.85) compared to the control group (1% for *2B/*2B and 4.4% for *4/*4). A significant association between lung cancer and homozygous ?2B/*2B passive smokers and *4/*4 ever (cigarettes) and passive smokers was also observed (p<0.05). Multivariate analysis revealed an increased risk for the *2B/2B genotype (OR 6.83), as well as for *4/*4 (OR 28.8). Conclusion: The results of the study indicate a significant association between *2B/*2B and *4/*4 genotypes and the risk of developing lung cancer among Mexicans. � 2008 Wichtig Editore

CYP1A1 *2B and *4 polymorphisms are associated with lung cancer susceptibility in Mexican patients

Background: CYP1A1 is a gene involved in the high aryl hydrocarbon hydroxylase -inducible phenotype, which is a genetically-determined variation among individuals that has been associated with lung cancer risk. More specifically, CYP1A1*2B and *4 polymorphisms have been associated with high susceptibility to lung cancer among cigarette smokers. Materials and methods: DNA was obtained from blood samples and we studied by PCR-RFLP the distribution of CYP1A1*2B (n=248) and *4 (n=222) polymorphisms in healthy controls and 222 lung cancer patients from a Mexican population. Results: Comparisons between groups showed an increased risk for lung cancer patients of *2B/*2B (18%; OR 7.6; 95% CI 3.0-19.2) and *4/*4 genotypes (15%; OR 11.45; 95% CI 2.19-59.85) compared to the control group (1% for *2B/*2B and 4.4% for *4/*4). A significant association between lung cancer and homozygous ≤2B/*2B passive smokers and *4/*4 ever (cigarettes) and passive smokers was also observed (p<0.05). Multivariate analysis revealed an increased risk for the *2B/2B genotype (OR 6.83), as well as for *4/*4 (OR 28.8). Conclusion: The results of the study indicate a significant association between *2B/*2B and *4/*4 genotypes and the risk of developing lung cancer among Mexicans. © 2008 Wichtig Editore

INCREASED HOMOCYSTEINE PLASMA LEVELS IN BREAST CANCER PATIENTS OF A MEXICAN POPULATION

Aim: Hyperhomocysteinemia has been associated with different pathologies, including cardiovascular diseases, hypertension, diabetes, and breast cancer (BC). To examine the differences in total homocysteine (tHcy) plasma levels, we compared healthy women to BC patients from a Mexican population. Materials and Methods: The tHcy plasma levels were measured using high-performance liquid chromatography with a fluorescence detector in 89 female controls and 261 BC patients. Results: The observed plasma tHcy levels were significantly higher among the BC patients (11.1019 ± 5.9161 µmol/l) compared to the controls (9.1046 ± 1.3213 µmol/l) (p = 0.002), and these differences were evident when stratified by age (≥ 50 years old), menopause status, overweight and obesity, miscarriages, node metastases, progression, subtype classification (luminal, Her2 and triple negative) and nonresponse to chemotherapy. Conclusions: The tHcy plasma levels could be a good marker for the progression and chemosensitivity of BC in the analyzed sample from a Mexican population. Key Words: plasma levels, homocysteine, HPLC, breast cancer, Mexican population