• Title/Summary/Keyword: case - control study

Search Result 6,386, Processing Time 0.035 seconds

4G/5G and A-844G Polymorphisms of Plasminogen Activator Inhibitor-1 Associated with Glioblastoma in Iran - a Case-Control Study

  • Pooyan, Honari;Ahmad, Ebrahimi;Azadeh, Rakhshan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.15
    • /
    • pp.6327-6330
    • /
    • 2015
  • Background: Glioblastoma is a highly aggressive and malignant brain tumor. Risk factors are largely unknown however, although several biomarkers have been identified which may support development, angiogenesis and invasion of tumor cells. One of these biomarkers is PAI-1.4G/5G and A-844G are two common polymorphisms in the gene promotor of PAI 1 that may be related to high transcription and expression of this gene. Studies have shown that the prevalence of the 4G and 844G allele is significantly higher in patients with some cancers and genetic disorders. Materials and Methods: We here assessed the association of 4G/5G and A-844G polymorphisms with glioblastoma cancer risk in Iranians in a case-control study. All 71 patients with clinically confirmed and 140 volunteers with no history and symptoms of glioblastoma as control group were screened for 4G/5G and A-844G polymorphisms of PAI-1, using ARMS-PCR. Genotype and allele frequencies of case and control groups were analyzed using the DeFinetti program. Results: Our results showed significant associations between 4G/5G (p=0.01824) and A-844G (p = 0.02012) polymorphisms of the PAI-1 gene with glioblastoma cancer risk in our Iranian population. Conclusions: The results of this study supporting an association of the PAI-1 4G/5G (p=0.01824) and A-844G (p = 0.02012) polymorphisms with increasing glioblastoma cancer risk in Iranian patients.

Association between assisted reproductive technology and autism spectrum disorders in Iran: a case-control study

  • Jenabi, Ensiyeh;Seyedi, Mahdieh;Hamzehei, Ronak;Bashirian, Saeid;Rezaei, Mohammad;Razjouyan, Katayoon;Khazaei, Salman
    • Clinical and Experimental Pediatrics
    • /
    • v.63 no.9
    • /
    • pp.368-372
    • /
    • 2020
  • Background: Autism spectrum disorder (ASD) is a neurodevelopmental disorder defined by impairments in social interaction and verbal and nonverbal communication. Purpose: Determine the association between use of assisted reproduction technology (ART) and the risk of ASD among children. Methods: This case-control study included 300 participants (100 cases, 200 controls). The control group included women with a child aged 2-10 years without ASD, while the cases were women with a child aged 2-10 years with ASD. We used a researcher-made questionnaire. Data were analyzed using Stata ver. 14 at the 0.05 significance level. Results: In the univariate analysis, there was significant association between child sex, delivery mode, history of preterm delivery, history of using ART, and maternal age at child's birth and the risk of ASD. After the adjustment for other variables, this association was significant for male sex (2.66; 95% confidence interval [CI], 1.11-4.31; P=0.001) and history of using ART (4.03; 95% CI, 1.76-9.21; P=0.001). Therefore, after the adjustment for confounder variables, there was no significant association between ART and the risk of ASD among children (4.98; 95% CI, 0.91-27.30; P=0.065). Conclusion: After the adjustment for other variables, risk factors for ASD were male sex and history preterm delivery. Thus, there was no significant association between ART and the risk of ASD among children.

Study on the Speed Control Code Design for Fixed Block TCS (고정폐색 열차제어시스템 속도제어코드 설계에 관한 연구)

  • Lee, Kang-Mi;Shin, Kyung-Ho;Shin, Duc-Ko;Lee, Jae-Ho
    • Journal of the Korean Society for Railway
    • /
    • v.15 no.1
    • /
    • pp.37-41
    • /
    • 2012
  • Kyung-Bu High Speed Railway is operated in train control system(tcs) of fixed block operated in a way of dividing track circuits into several blocks in accordance with operation circumstances such as rolling stocks, grade, curves and facilities. The TCS of fixed block system refers to a continuous train control system, which transfers operational information such as entry and exit speed, distance-to-go, and deceleration etc. into on-board train control equipment on the basis of block occupancy of a preceding train. It guarantees a safe operation of trains by giving an emergency braking order, in case that a train exceeds an entry and exit speed of a corresponding block. In this paper, we analyze the speed control code deducing in accordance with maximum operation speed and characteristics of rolling stocks by analyzing principles of generation of speed control code allocated in blocks for safe operation, then train operational efficiency was analyzed by means of analysis of operation headway in accordance with the deduced speed control code. This study will be used to design in case of getting an increase in speed for existing high speed line or new high speed line TCS.

H-TMD with hybrid control method for vibration control of long span cable-stayed bridge

  • Han, Bing;Yan, Wu Tong;Cu, Viet Hung;Zhu, Li;Xie, Hui Bing
    • Earthquakes and Structures
    • /
    • v.16 no.3
    • /
    • pp.349-358
    • /
    • 2019
  • Long span cable-stayed bridges are extremely vulnerable to dynamic excitations such as which caused by traffic load, wind and earthquake. Studies on cable-stayed bridge vibration control have been keenly interested by researchers and engineers in design new bridges and assessing in-service bridges. In this paper, a novel Hybrid-Tuned Mass Damper (H-TMD) is proposed and a hybrid control model named Mixed Logic Dynamic (MLD) is employed to build the bridge-H-TMD system to mitigate the vibrations. Firstly, the fundamental theory and modeling process of MLD model is introduced. After that, a new state switching design of the H-TMD and state space equations for different states are proposed to control the bridge vibrations. As the state switching designation presented, the H-TMDs can applied active force to bridge only if the structural responses are beyond the limited thresholds, otherwise, the vibrations can be reduced by passive components of dampers without active control forces provided. A new MLD model including both passive and active control states is built based on the MLD model theory and the state switching design of H-TMD. Then, the case study is presented to demonstrate the proposed methodology. In the case study, the control scheme with H-TMDs is applied for a long span cable-stayed bridge, and the MLD model is established and simulated with earthquake excitation. The simulation results reveal that the suggested method has a well damping effect and the established system can be switched between different control states as design excellently. Finally, the energy consumptions of H-TMD schemes are compared with that of Active Tuned Mass Damper (ATMD) schemes under variable seismic wave excitations. The compared results show that the proposed H-TMD can save energy than ATMD.

Fat intake and breast cancer: a review

  • Cho, Eun-Young
    • International Journal of Human Ecology
    • /
    • v.4 no.2
    • /
    • pp.101-106
    • /
    • 2003
  • The relationship between fat intake and breast cancer has been debated for a long period of time. Animal, ecological, and case-control studies have supported that dietary fat increases breast cancer risk. However, cohort studies have not support any strong association between dietary fat intake and breast cancer risk. It has not been clear whether fat per se or some specific type of fat is responsible for the increased risk. Recently, a few cohort studies have found some positive association between specific types of fat intake, but not overall fat intake and breast cancer risk. In this review, the findings from previous studies will be summarized with advantages and disadvantages of different types of study design and recent findings will be introduced.

Current Status of Genomic Epidemiology Reseach (유전체 역학연구의 동향)

  • Lee, Kyoung-Mu;Kang, Dae-Hee
    • Journal of Preventive Medicine and Public Health
    • /
    • v.36 no.3
    • /
    • pp.213-222
    • /
    • 2003
  • Genomic epidemiology is defined as 'an evoking field of inquiring that uses the systematic application of epidemiologic methods are approaches in population-based studies of the impact of human genetic variation on health and disease (Khoury, 1998)'. Most human diseases are caused by the intricate interaction among environmental exposures and genetic susceptibility factors. Susceptibility genes involved in disease pathogenesis are categorized into two groups: high penetrance genes (i.e., BRAC1, RB, etc.) and lour penetranoe genes (i.e., GSTs, Cyps, XRCC1, ets.), and low penetrance susceptibility genes has the higher priority for epidemiological research due to high population attributable risk. In this paper, the summarized results of the association study between single nucleotide polymorphisms (SNPs) and breast cancer in Korea were introduced and the international trends of genomic epidemiology research were reviewed with an emphasis on internee-based case-control and cohort consortium.

Detecting Genetic Association and Gene-Gene Interaction using Network Analysis in Case-Control Study

  • Jin, Seo-Hoon;Lee, Min-Hee;Lee, Hyo-Jung;Park, Mi-Ra
    • The Korean Journal of Applied Statistics
    • /
    • v.25 no.4
    • /
    • pp.563-573
    • /
    • 2012
  • Various methods of analysis have been proposed to understand the gene-disease relation and gene-gene interaction effect for a disease through comparison of genotype in case-control study. In this study, we proposed the method to detect a genetic association and gene-gene interaction through the use of a network graph and centrality measures that are used in social network analysis. The applicability of the proposed method was studied through an analysis of real genetic data.

Role of Electromagnetic Field Exposure in Childhood Acute Lymphoblastic Leukemia and No Impact of Urinary Alpha-Amylase - a Case Control Study in Tehran, Iran

  • Tabrizi, Maral Mazloomi;Hosseini, Seyed Ahmad
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.17
    • /
    • pp.7613-7618
    • /
    • 2015
  • Childhood acute lymphoblastic leukemia (ALL) is one of the most common hematologic malignancies which accounts for one fourth of all childhood cancer cases. Exposure to environmental factors around the time of conception or pregnancy can increase the risk of ALL in the offspring. This study aimed to evaluate the influence of prenatal and postnatal exposure to high voltage power lines on the incidence of childhood ALL. It also examines the role of various factors such as environmental factors and alpha-amylase as a marker in the development of leukemia.This cross-sectional case control study was carried out on 22 cases and 100 controls who born and lived in low socioeconomic families in Tehran and were hospitalized for therapeutic purposes in different hospitals ofrom 2013-2014. With regard to the underlying risk factors; familial history and parental factors were detected as risk factors of ALL but in this age, socioeonomic and zonal matched case control study, prenatal and childhood exposure to high voltage power lines was considered as the most important environmental risk factor (p=0.006, OR=3.651, CI 95% 1.692-7.878). As the population study was from low socioeconomic state, use of mobiles, computers and microwaves was negligible. Moreover prenatal and postnatal exposure to all indoor electrically charged objects were not detected as significant environmental factors in the present study. This work defined the risk of environmental especially continuous pre and postnatal exposure to high voltage power lines and living in pollutant regions through the parents or children as well as the previously described risk factors of ALL for the first time in low socioeconomic status Iranian population.

Leu432Val Polymorphism of CYP1B1 is Not Associated with Squamous Cell Carcinoma of Esophagus - a Case-Control Study from Kashmir, India

  • Shah, Idrees Ayoub;Mehta, Promila;Lone, Mohd Maqbool;Dar, Nazir Ahmad
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.13
    • /
    • pp.5337-5341
    • /
    • 2015
  • Background: Individual susceptibility to cancer has been attributed to polymorphisms in xenobiotic metabolizing genes. To evaluate the association of the Leu432Val polymorphism of cytochrome P4501B1 (CYP1B1) with esophageal squamous cell carcinoma (ESCC), we conducted a case control study in Kashmir, India, an area with a relatively high incidence of ESCC. Materials and Methods: We recruited 404 histopathologically confirmed ESCC cases, and an equal number of controls, individually matched for sex, age and district of residence to respective cases. Information was obtained on various dietary, lifestyle and environmental factors in face to face interviews, using a structured questionnaire, from each subject. Genotypes were analysed by polymerase chain reaction, restriction fragment length polymorphism and sequencing of randomly selected samples. Conditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). Results: Among the three possible variants, we did not find any Leu432Leu genotype of CYP1B1 in the study population and the genotypic distribution of Val432Val and Leu432Val carriers was nearly equal in both cases (89.6% and 10.4%) and controls (88.9% and 11.1%) respectively. We did not find any risk associated with this polymorphism in the current study (OR = 0.64; 95% CI: 0.55 - 1.64). Conclusions: The study indicates that (Leu432Val) polymorphism of CYP1B1, is not associated with ESCC risk. However, replicative studies with larger sample size are needed to substantiate the findings.

A Case Study on Designing a Console Design Review System Considering Operators' Viewing Range and Anthropometric Data

  • Cha, Woo Chang;Choi, Eun Gyeong
    • Journal of the Ergonomics Society of Korea
    • /
    • v.36 no.5
    • /
    • pp.373-383
    • /
    • 2017
  • Objective: The aim of this study is to introduce an operator console design review system suitable for designing and evaluating consoles based on human factor guidelines for a digitalized main control room in an advanced nuclear power plant which has a requirement for anthropometric data usage. Background: The system interface of the main control room in a nuclear power plant has been getting digitalized and consists of various consoles with many information displays. Console operators often face human-computer interactive problems due to inappropriate console design stemming from the perceptual constraints of anthropometric data usage. Method: Computational models with a process of visual perception and variables of anthropometric data are used for designing and evaluating operator consoles suitable for human system interface guidelines, which are used in an advanced nuclear power plant. Results: From the computational model and simulation application, console dimensions and a designing test module, which would be used for designing suitable consoles with safety concerns in a nuclear power plant, have been introduced. Conclusion: This case study may influence employing a suitable design concept with various anthropometric data in many areas with safety concerns and may show a feasible solution to designing and evaluating the safety console dimensions. Application: The results of this study may be used for designing a control room with the human factors requiring a safe working environment.