Gene Polymorphisms of Costimulatory Molecules: CTLA-4/CD28/ICOS Are Associated with B-Cell Chronic Lymphocytic Leukemia (B-CLL).

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2074-2074 ◽  
Author(s):  
Irena Frydecka ◽  
Katarzyna Suwalska ◽  
Edyta Pawlak ◽  
Lidia Karabon ◽  
Anna Tomkiewicz ◽  
...  

Abstract There are strong evidences that altered immunological function entails an increased risk of cancer. Cytotoxic T-lymphocyte antigen 4 (CTLA-4), CD28, and Inducible co-stimulator (ICOS) are costimulatory molecules provide regulatory signals for T-cell activation. CD28 and ICOS potently enhance T-cell functions, while activation of T-cells is subsequently downregulated by CTLA-4. The abnormal expression of costimulatory molecules may be caused by polymorphisms of genes encoding these molecules. The extended study was undertaken to evaluate the association between the polymorphisms: CTLA-4+49A/G, CTLA-4-319C/T, CTLA-4(AT)n, CD28+17C/T, ICOS(GT)n and susceptibility to B-CLL in a Polish population. All together 124 B-CLL patients and 202 controls were studied. Single nucleotide polymorphisms were typed by minisequencing. The microsatellite polymorphisms were studied by PCR and fuorescence based technique. The distribution of -319T/C alleles and genotypes differed significantly between groups. The frequency of T allele and T phenotype was increased in patients with respect to controls (p=0.01, OR=1.74, 1.13∼95%CI∼2.68; p=0.01, OR =1.85, 1.13∼95%CI∼3.04, respectively). CTLA-4+49A/G and CTLA-4 (AT)n did not correlate with B-CLL. The analysis of the CD28+17C/T showed that the presence of C allele and C phenotype increased the OR of B-CLL by 1.97 and 2.07, respectively (p=0.002, 1.28∼95%CI ∼3.03; p=0.003, 1.27∼95%CI ∼3.38). For ICOS(GT)n gene polymorphism analysis we combined the alleles into 3 groups: (s)- short-alleles with 8 and 9 repeats, (m) -middle- with 10 and 11 and (l)- long- 12 and more repeats. The global distribution of alleles and genotypes was significantly different in patients and controls (p=0.00008 and p=0.00006, respectively). Individuals possessing (s) alleles were 2.75 times more prone to B-CLL than others (p=0.0000, OR=2.75, 1.67∼95%CI∼4.55), while carrying (l) alleles were protected to B-CLL (p=0.004, OR=0.47, 0.29∼95%CI∼0.79). The genotype (s)/(m) was overrepresented in patients (p=0.004, OR=2.29, 1.28∼95%CI∼2.09), but (l)/(l) individuals appeared more frequently in controls (p=0.002, OR=0.07, 0.00 ∼95%CI∼0.44). The haplotype association study of three polymorphic sites: CTLA-4-319C/T and CD28+17C/T and ICOS (s)/(m)/(l), which correlated with B-PBL in univariante analysis, showed that the distribution of haplotypes was different in cases and control, global p value was p= 3 ×108. Remarkable, the haplotypes T/C/(s) and T/T/(s) were presented only in B-CLL (p=0.0004, OR=62072, 3540∼95%CI∼1088238; p=0.00003, OR=3447, 203∼95%CI∼58334, respectively) while the haplotype C/T/(l) was significantly more frequent in control group as compared to B-CLL (p=0.000003, OR=0.3, 0.18∼95%CI∼0.51). B-CLL patients and controls polymorphic features for CTLA-4-319C/T, CD28IVS3+17C/T, ICOS (GT)n were subjected to multivariate forward stepwise logistic regression analysis. It appeared that C phenotype at CD28 T17int3C site increased twice risk of B-CLL (p=0.004, OR=2.09; 1.26∼95%CI∼3.48), while genotype (m)/(l) or (l)/(l) for ICOS gene protected from disease (p=0,0009, OR=0,41; 0,24∼95%CI∼0,69). We reported for the first time that the gene polymorphism of costimulatory molecules: CTLA-4/CD28/ICOS contribute to susceptibility to B-CLL.

Author(s):  
Jenny Stritzelberger ◽  
Johannes D. Lang ◽  
Tamara M. Mueller ◽  
Caroline Reindl ◽  
Vivien Westermayer ◽  
...  

Abstract Objective Whether anti-seizure medication (ASM) increases the risk for cancer has been debated for decades. While for some ASM, a carcinoma-promoting effect has been suspected, carcinoma-protective effects have been shown for other ASM. However, the issue remains unresolved as data from preclinical and clinical studies have been inconsistent and contradictory. Methods We collected anonymous patient data from practice neurologists throughout Germany between 2009 and 2018 using the IMS Disease Analyzer database (QuintilesIMS, Frankfurt, Germany). People with epilepsy (PWE) with an initial cancer diagnosis and antiepileptic therapy prior to the index date were 1:1 matched with a control group of PWE without cancer according to age, gender, index year, Charlson Comorbidity Index, and treating physician. For both groups, the risk to develop cancer under treatment with different ASMs was analyzed using three different models (ever use vs. never use (I), effect per one (II) and per five therapy years (III). Results A total of 3152 PWE were included (each group, n = 1,576; age = 67.3 ± 14.0 years). The risk to develop cancer was not significantly elevated for any ASM. Carbamazepine was associated with a decreased cancer risk (OR Model I: 0.699, p < .0001, OR Model II: 0.952, p = .4878, OR Model III: 0.758, p < .0004). Significance Our findings suggest that ASM use does not increase the risk of cancer in epilepsy patients.


2020 ◽  
pp. bjophthalmol-2020-316947
Author(s):  
Min Seok Kim ◽  
Joon Hee Cho ◽  
Seong Jun Byun ◽  
Chang-Mo Oh ◽  
Kyu Hyung Park ◽  
...  

AimsTo investigate the association between incident retinal vein occlusion (RVO) and the subsequent development of cancer.MethodsIn this nationwide population-based retrospective study using 2002–2013 National Health Insurance Service database which covers the entire South Korean population, 186 701 incident RVO patients and their 1:1 propensity-score matched controls were included. We defined the fixed cohort from January 1st, 2004 to December 31st, 2013; the cohort included patients who suffered incident RVO after entering the cohort and their matched controls, and excluded patients having any cancer history before entering the cohort. The association of RVO and cancer was assessed by time-varying covariate Cox regression models; Model 1 included RVO as a time-varying covariate, Model 2 included Model 1 plus demographic information and Model 3 included Model 2 and comorbidities.ResultsRVO was associated with an increased risk of subsequent cancer (HR=1.29; 95% CI, 1.26–1.31 in Model 1), which was consistent in Models 2 and 3. The incidence rate of overall cancer during the study period was 25.55 (95% CI, 25.19–25.91) per 1000 person-years in the RVO group and 18.62 (95% CI, 18.46–18.79) per 1000 person-years in the control group. In the subgroup analysis, haematological malignancies showed the highest association with RVO (HR=1.65; 95% CI, 1.49–1.83).ConclusionPatients with RVO have an increased risk of subsequent cancer development even after adjusting for demographic factors and comorbidities. Further study is warranted to elucidate these associations to provide proper recommendations for RVO patients regarding the cancer screening.


2020 ◽  
Vol 8 (2) ◽  
pp. e001439 ◽  
Author(s):  
Rafael Cubas ◽  
Zia Khan ◽  
Qian Gong ◽  
Marina Moskalenko ◽  
Huizhong Xiong ◽  
...  

BackgroundCancer immunotherapy has evolved from interferon-alpha (IFNα) and interleukin-2 in the 1980s to CTLA-4 and PD-1/PD-L1 checkpoint inhibitors (CPIs), the latter highlighting the importance of enhancing T-cell functions. While the search for novel immunomodulatory pathways continues, combination therapies augmenting multiple pathways can also increase efficacy. The association of autoimmune-related adverse events with clinical efficacy following CPI treatment has been inferred and suggests that breaking tolerance thresholds associated with autoimmunity may affect host immune responses for effective cancer immunotherapy.ResultsHere, we show that loss of autoimmune associated PTPN22, a key desensitization node for multiple signaling pathways, including IFNα receptor (IFNAR) and T-cell receptor, can augment tumor responses. Implantation of syngeneic tumors in Ptpn22-/- mice led to expansion and activation of peripheral and intratumoral T cells and, in turn, spontaneous tumor regression as well as enhanced responses in combination with anti-PD-L1 treatment. Using genetically modified mice expressing a catalytically inactive PTPN22 or the autoimmunity-associated human single-nucleotide polymorphism variant, augmentation of antitumor immunity was dependent on PTPN22 phosphatase activity and partially on its adaptor functions. Further, antitumor responses were dependent on both CD4+ and CD8+T cells and, in part, IFNAR function. Finally, we demonstrate that the autoimmune susceptibility Ptpn22(C1858T) variant is associated with lower risk of developing non-melanoma skin cancers, improved overall survival and increased risk for development of hyperthyroidism or hypothyroidism following atezolizumab (anti-PD-L1) treatment.ConclusionsTogether, these data suggest that inhibition of PTPN22 phosphatase activity may provide an effective therapeutic option for cancer immunotherapy and that exploring genetic variants that shift immune tolerance thresholds may serve as a paradigm for finding new cancer immunotherapy targets.


2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e12018-e12018
Author(s):  
Bruno Gustavo Muzzi Carvalho Carneiro ◽  
Andy Petroianu ◽  
Rafael Augusto Ribeiro Carvalho ◽  
Thiago Neto Ribeiro ◽  
Ana Maria Santos Rodrigues

e12018 Background: Many studies have suggested an inverse association between allergies and cancer, while others have found no relation between them, and still others have shown an increased risk of cancer in allergy patients. The conflicting findings from prior studies are partially due to the chosen research method, such as different definitions and measures for atopy, in addition to variations in the control of confusion factors, such as smoking and obesity. Objectives: Verify if there is a relation between certain types of cancer and allergies; investigate if there is a difference between individuals with and without cancer in relation to allergies. Methods: Case-control study carried out at the Alberto Cavalcanti Hospital of the Hospital Foundation of the State of Minas Gerais (FHEMIG), Brazil, from 2009 to 2011. The study included patients over 18 years of age, from both genders, who presented a diagnosis of cancer, as compared to healthy individuals, paired by gender and age. An anamnesis was gathered considering the medical history of the allergy, as diagnosed by a doctor, as well as the patients’ habits, associated illnesses, and the use of medications. For cancer patients, data concerning the tumor were recorded. Subsequently, an allergy percutaneous test was performed in each group to detect allergic hyperreactivity toward common inhalable, bacterial, and food antigens within our everyday environment. A blood sample was collected to quantitatively evaluate the eosinophils. Results: Both groups were paired according to interest variables, and eventual deviations were adjusted by means of multivariate analysis. Reports of allergies occurred in 30% of the patients in the cancer group, as compared to 53% in the control group (p<0.05), whereas in the cutaneous tests, a greater positivity occurred in the cancer group (69%) than in the control group (51%, p<0.05). No difference in the eosinophil values could be observed within the groups. Conclusions: Cancer patients present fewer allergies. By contrast, in cancer patients, positive cutaneous tests detected allergies which did not correspond to the clinical findings. Therefore, in cancer patients, the positive cutaneous test for allergies does not present a direct relation to the presence of clinically detectable allergies.


2017 ◽  
Vol 35 (7_suppl) ◽  
pp. 49-49
Author(s):  
Sean Mackay ◽  
Brianna Flynn ◽  
Kevin Morse ◽  
Patrick Paczkowski ◽  
Antonella Bacchiocchi ◽  
...  

49 Background: Functional alteration of tumor-infiltrating T lymphocytes (TILs) may serve as a predictor for clinical outcome in cancer patients receiving immunotherapy.To evaluate TILs function unleashed by anti-PD-1 blocking, we employed a single-cell technology integrated with automated bioinformatics to simultaneously measure 17 cytokines secreted by single TILs, permitting the full spectrum delineation of anti-tumor T cell functions in patients with metastatic melanoma. Methods: TILs were enriched from biopsied melanoma tissues digested with enzymes, stimulated with anti-CD3 at 37°C, 5% CO2 for 24 hrs and loaded into a single-cell barcode chip (SCBC) containing ~12000 microchambers. Each chamber (~1.2 nl) was pre-patterned with a complete copy of a 17-plex antibody array. Cells on the SCBC were imaged and incubated for 16 hrs at 37°C, 5% CO2; single-cell cytokine signals were captured with a microarray scanner. The polyfunctional expression (2+ cytokines per cell) of single TILs was evaluated across 4 groups: Effector (Granzyme B, IFN-γ, MIP-1α, Perforin, TNF-α), Stimulatory (GM-CSF, IL-2, IL-5, IL-8, IL-9), Regulatory (IL-4, IL-10, IL-13, IL-22), and Inflammatory (IL-6, IL-17A, MCP-1). Results: Single-cell TILs analysis revealed significant increase of polyfunctional cytokines in patients who responded to anti-PD-1 therapy, compared to those resistant to therapy or in the control group. It was further revealed that the major contributions to enhanced polyfunctional strength are dominated by effector and stimulatory cytokines – both associated with anti-tumor immunity. Notably, TILs of patients responding to therapy exhibited polyfunctional secretions containing a subset of cells co-secreting Granzyme B, IFN- γ, MIP-1 α, and IL-8, which upon further validation is potentially a biomarker to predict clinical outcome of melanoma patients treated by checkpoint immunotherapy. Conclusions: Single-cell multiplexed cytokine profiling is capable of dissecting the full spectrum of immune functions associated with anti-tumor T cell immunity and more accurately measuring the function of TILs for predicting the response of patients receiving anti-PD-1 blocking therapy.


2016 ◽  
Vol 19 (1) ◽  
pp. 63-70 ◽  
Author(s):  
D Popović ◽  
J Nikolajević Starčević ◽  
M Šantl Letonja ◽  
J Makuc ◽  
A Cokan Vujkovac ◽  
...  

ABSTRACTThe platelet endothelial cell adhesion molecule 1 (PECAM-1) plays an important role in many inflammatory processes, including the development of atherosclerosis. Polymorphism rs668 of the PECAM-1 gene (373C/G) is functional, and it was reported to be associated with increased serum levels of PECAM-1. We investigated the association between the rs668 polymorphism of PECAM-1 and subclinical markers of carotid atherosclerosis in subjects with type 2 diabetes mellitus (T2DM). Five hundred and ninety-five T2DM subjects and 200 control subjects were enrolled. The carotid intima-media thickness (CIMT) and plaque characteristics (presence and structure) were assessed ultrasonographically. Biochemical analyses were performed using standard biochemical methods. Geno-typing of the PECAM-1 gene polymorphism (rs668) was performed using KASPar assays. The control examinations were performed 3.8 ± 0.5 years after the initial examination. Higher CIMT was found in patients with T2DM in comparison with subjects without T2DM. Statistically sig-nificantly faster progression of the atherosclerotic markers was shown in subjects with T2DM in comparison with the control group. When adjusted to other risk factors, the rs668 GG genotype was associated with an increased risk of carotid plaques in subjects with T2DM. We concluded that our study demonstrated a minor effect of the rs668 PECAM-1 on markers of carotid atherosclerosis in subjects with T2DM.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jialei Chen ◽  
Jing He ◽  
Jing Luo ◽  
Shixun Zhong

Objective: The etiology of sudden sensorineural hearing loss (SSNHL) is still unknown. It has been demonstrated that normal endolymph metabolism is essential for inner ear function and that epithelial sodium channels (ENaC) may play an important role in the regulation of endolymphatic Na+. This study aimed to explore the potential association between αENaC p. Ala663Thr gene polymorphism and SSNHL.Methods: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to examine the genotype and allele frequency of the αENaC p. Ala663Thr polymorphism in 20 cases of low-frequency SSNHL (LF-SSNHL), 19 cases of high-frequency SSNHL (HF-SSNHL), 31 cases of all frequency SSNHL (AF-SSNHL), 42 cases of profound deafness SSNHL (PD-SSNHL), and 115 normal controls.Results: The T663 allele was found to be significantly associated with an increased risk of LF-SSNHL (p = 0.046, OR = 2.16, 95% CI = 1.01–4.62). The TT genotype and T663 allele, on the other hand, conferred a protective effect for PD-SSNHL (AA vs. TT: p = 0.012, OR = 0.25, 95% CI = 0.08–0.74; A vs. T: p = 0.001, OR = 0.36, 95% CI = 0.21–0.61). However, there was no statistically significant difference in genotype or allele frequency between the two groups (HF-SSNHL and AF-SSNHL) and the control group.Conclusion: The αENaC p. Ala663Thr gene polymorphism plays different roles in different types of SSNHL.


Author(s):  
Ю.Э. Азарова

Общим патогенетическим звеном сахарного диабета 2 типа (СД2) и ишемической болезни сердца (ИБС) является окислительный стресс, развивающийся в результате дисбаланса продукции активных форм кислорода (АФК) и их обезвреживания системой антиоксидантной защиты. Нейтрофильный цитозольный фактор 4 (NCF4) непосредственно вовлечен в синтез супероксид-аниона в составе НАДФН-оксидазы. Целью настоящего исследования стало изучение ассоциаций восьми однонуклеотидных полиморфизмов гена NCF4 rs5995355 (A>G), rs5995357 (T>A), rs1883112 (G>A), rs4821544 (G>A), rs760519 (T>C), rs729749 (C>T), rs2075938 (G>A) и rs2075939 (C>T) с предрасположенностью к СД2, а также с риском развития ИБС у пациентов с СД2. В исследование включено 1579 пациентов с СД2 (у 448 из которых была также диагностирована ИБС) и 1627 условно здоровых добровольцев. Генотипирование выполнено методом MALDI-TOF масс-спектрометрии на платформе MassArray Analyzer 4. Статистическую обработку полученных данных проводили с помощью онлайн программы SNPStats. Частоты аллелей и генотипов изучаемых SNPs у больных СД2 не отличались от таковых в группе контроля (р>0,05). Установлены ассоциации генотипов rs4821544-C/С (OR 1,71, 95CI 1,12-2,59, р=0,013) и rs5995357-А/А (OR 3,74, 95CI 1,14-12,31, р=0,026) с предрасположенностью к ИБС у больных СД2 женщин. Несмотря на отсутствие ассоциаций изучаемых SNPs гена NCF4 с ИБС у мужчин, именно у представителей мужского пола выявлены ассоциации гаплотипической структуры NCF4 (р=0,0064), а также гаплотипов Н2 (OR 1,79, 95CI 1,16-2,76, р=0,0085) и Н3 (OR 1,77, 95CI 1,06-2,97, р=0,03) с повышенным риском развития ИБС при СД2. Кроме того, выявлены не зависящие от пола ассоциации генотипа rs4821544-С/С с повышенным уровнем гликированного гемоглобина HbA1c (р=0,032) и окисленного глутатиона плазмы крови (p=0.049) у пациентов с ИБС и СД2. В этой же категории больных носительство гаплотипов Н4 rs5995355G-rs5995357A-rs1883112G-rs4821544C-rs760519T-rs729749C-rs2075938G-rs2075939C и Н10 rs5995355A-rs5995357T-rs1883112G-rs4821544C-rs760519T-rs729749C-rs2075938A-rs2075939C гена NCF4 ассоциировалось с повышением содержания HbA1c на 8,67% (р=0,011) и 6,27% (р=0,038), соответственно. Полученные данные свидетельствуют о значимом вкладе полиморфизма гена NCF4 в патогенез ИБС у пациентов с СД2 и создают научный задел для разработки таргетной терапии и профилактики этой патологии. A common pathogenic link in type 2 diabetes mellitus (T2D) and coronary artery disease (CAD) is oxidative stress, which develops as a result of an imbalance in the production of reactive oxygen species (ROS) and their neutralization by the antioxidant defense system. Neutrophilic cytosolic factor 4 (NCF4) is directly involved in the synthesis of superoxide anion as part of NADPH oxidase. In this regard, the purpose of this study was to investigate the associations of eight single nucleotide polymorphisms of the NCF4 gene rs5995355 (A>G), rs5995357 (T>A), rs1883112 (G>A), rs4821544 (G>A), rs760519 (T>C), rs729749 (C>T), rs2075938 (G>A), rs2075939 (C>T) with a predisposition to T2D, as well as the risk of developing CAD in patients with T2D. The study included 1579 patients with T2D (448 of them were also diagnosed with CAD) and 1627 relatively healthy volunteers. Genotyping was performed using MALDI-TOF mass spectrometry on the MassArray Analyzer 4 platform. Statistical processing of the obtained data was carried out using the SNPStats online program. The allele and genotype frequencies of the studied SNPs in T2D patients did not differ from those in the control group (p>0.05). Associations of genotypes rs4821544-C/C (OR 1.71, 95CI 1.12-2.59, p=0.013) and rs5995357-A/A (OR 3.74, 95CI 1.14-12.31, p=0.026) with a predisposition to CAD in diabetic females were established. Despite the absence of associations of the studied SNPs NCF4 with CAD in males, associations of the haplotype structure of NCF4 (p=0.0064), as well as the haplotypes H2 (OR 1.79, 95CI 1.16-2.76, p=0.0085) and H3 (OR 1.77, 95CI 1.06-2.97, p=0.03) with an increased risk of CAD were observed exclusively in diabetic males. In addition, a sex-independent relationship of the rs4821544-C/C genotype with an increased level of glycated hemoglobin (p=0.032) and oxidized glutathione (p=0.049) was revealed in patients with CAD and T2D. In the same category of patients haplotypes H4 rs5995355G-rs5995357A-rs1883112G-rs4821544C-rs760519T-rs729749C-rs2075938G-rs2075939C and H10 rs5995355A-rs5995357T-rs1883112G-rs4821544C-rs760519T-rs729749C-rs2075938A-rs2075939C of NCF4 gene were associated with an increase in the content of HbA1c 8.67 % (p=0.011) and 6.27% (p=0.038), respectively. The data obtained indicate a significant contribution of the NCF4 gene polymorphism to the pathogenesis of CAD in patients with T2D and create a scientific basis for the development of targeted therapy and prevention of this pathology.


2015 ◽  
Vol 87 (3) ◽  
Author(s):  
Jacek Kabziński ◽  
Ireneusz Majsterek ◽  
Michał Mik ◽  
Adam Dziki ◽  
Łukasz Dziki ◽  
...  

AbstractColorectal cancer (CRC) is one of the deadliest cancers which lie in the incidence of morbidity in second place. Intensive research is to determine and confirm the genetic basis of this disease, which is believed may have a direct relationship with the reduced efficiency of DNA repair systems.The aim of this study was to determine the effect of APEX gene polymorphism Ile64Val on increasing the risk of colorectal cancer in the Polish population.Material and methods. The blood samples collected from 150 patients diagnosed with colon cancer was used. The control group consisted of 150 healthy subjects. Genotyping was performed by TaqMan method.Results. The results indicate that genotype Ile Val is associated with an increased risk of colorectal cancer (OR 2.069; 95% CI 1,205-3,552; p = 0.008).Conclusions. Based on these results, we conclude that the APEX gene polymorphism Ile64Val may be associated with an increased risk of colorectal cancer.


2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Yang Song ◽  
Zhenwu Du ◽  
Ming Ren ◽  
Qiwei Yang ◽  
Yujie Sui ◽  
...  

Sex determining region Y-box 9 (SOX9) is a key transcription factor involved in cartilage formation during the embryonic development stage and cartilage growth and repair after birth. To explore the roles of polymorphism and expression of the SOX9 gene in the development of osteonecrosis of the femoral head (ONFH), we analyzed the polymorphism of rs12601701 [A/G] and rs1042667 [A/C] and the serum protein expression of the SOX9 gene in 182 patients with ONFH and 179 healthy control subjects. Results revealed that the A-A haplotype of SOX9 gene as well as the GG and AA genotypes of rs12601701 was significantly associated with increased ONFH risk (P=0.038) and the risk of bilateral hip lesions of ONFH (P=0.009), respectively. The C-A, A-A, and A-G haplotypes were also statistically associated with the decreased and increased risk of bilateral hip lesions of ONFH (P=0.03,P=0.048, andP=0.013), respectively, while the A-A haplotype closely related to the clinical stages of ONFH (P=0.041). More importantly, the serum SOX9 protein expression of the ONFH group was greatly decreased compared to control group (P=0.0001). Our results first showed that the gene polymorphism and gene expression of SOX9 were significantly associated with the risk and clinical phenotypes of ONFH and also indicate that the SOX9 gene may play a key role in the development of ONFH.


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