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Find video protocols related to scientific articles indexed in Pubmed.
An Epidemiologic Investigation of Physical Activity and Breast Cancer Risk in Africa.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 09-21-2014
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Physical activity (PA) is modifiable and linked to decreased breast cancer risk but its impact has not been investigated among indigenous African populations.
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A comprehensive examination of breast cancer risk loci in African American women.
Hum. Mol. Genet.
PUBLISHED: 05-22-2014
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Genome-wide association studies have identified 73 breast cancer risk variants mainly in European populations. Given considerable differences in linkage disequilibrium structure between populations of European and African ancestry, the known risk variants may not be informative for risk in African ancestry populations. In a previous fine-mapping investigation of 19 breast cancer loci, we were able to identify SNPs in four regions that better captured risk associations in African American women. In this study of breast cancer in African American women (3016 cases, 2745 controls), we tested an additional 54 novel breast cancer risk variants. Thirty-eight variants (70%) were found to have an association with breast cancer in the same direction as previously reported, with eight (15%) replicating at P < 0.05. Through fine-mapping, in three regions (1q32, 3p24, 10q25), we identified variants that better captured associations with overall breast cancer or estrogen receptor positive disease. We also observed suggestive associations with variants (at P < 5 × 10(-6)) in three separate regions (6q25, 14q13, 22q12) that may represent novel risk variants. Directional consistency of association observed for ?65-70% of currently known genetic variants for breast cancer in women of African ancestry implies a shared functional common variant at most loci. To validate and enhance the spectrum of alleles that define associations at the known breast cancer risk loci, as well as genome-wide, will require even larger collaborative efforts in women of African ancestry.
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Voluntary participation and comprehension of informed consent in a genetic epidemiological study of breast cancer in Nigeria.
BMC Med Ethics
PUBLISHED: 05-01-2014
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Studies on informed consent to medical research conducted in low or middle-income settings have increased, including empirical investigations of consent to genetic research. We investigated voluntary participation and comprehension of informed consent among women involved in a genetic epidemiological study on breast cancer in an urban setting of Nigeria comparing women in the case and control groups.
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Alcohol consumption and breast cancer risk among women in three sub-Saharan African countries.
PLoS ONE
PUBLISHED: 01-01-2014
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Alcohol drinking is linked to the development of breast cancer. However, there is little knowledge about the impact of alcohol consumption on breast cancer risk among African women.
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Neo-adjuvant capecitabine chemotherapy in women with newly diagnosed locally advanced breast cancer in a resource-poor setting (Nigeria): efficacy and safety in a phase II feasibility study.
Breast J
PUBLISHED: 07-19-2013
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The majority of clinical trials of neo-adjuvant therapy for breast cancer have been conducted in resource-rich countries. We chose Nigeria, a resource-poor country, as the major site for a phase II feasibility open-label multicenter clinical trial designed to evaluate the efficacy, safety, and tolerability of neo-adjuvant capecitabine in locally advanced breast cancer (LABC). Planned treatment consisted of 24 weeks of capecitabine at a dose of 1,000 mg/m(2) twice daily (2,000 mg/m(2) total per day). The primary endpoints were overall, partial, complete clinical response rate (OCR, PCR, CCR) and complete pathologic response (cPR). A total of 16 patients were recruited from August 2007 to April 2010. The study was terminated early as a result of slow accrual. After the first three cycles of therapy, PCR were seen in five of 16 patients (31%; 95% CI 11-59%). Of the remaining 11 patients, eight had no response (NR) or stable disease (SD), and three had progressive disease (PD). Seven patients proceeded with further therapy of which had SD. OCR at the end of eight cycles was 44% (95% CI 20-70%). Clinical response and radiologic response by ultrasonomammography were highly concordant (spearman correlation 0.70). The most common adverse effect was Grade 1 hand-foot syndrome, which was seen in 75% of patients. Despite several limitations, we successfully carried out this phase II feasibility study of neo-adjuvant capecitabine for LABC in Nigeria. Capecitabine monotherapy showed good overall response rates with minimal toxicity and further studies are warranted.
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Risk factors for pregnancy-associated breast cancer: a report from the Nigerian Breast Cancer Study.
Ann Epidemiol
PUBLISHED: 05-17-2013
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Little is known about risk factors for pregnancy-associated breast cancer (PABC), diagnosed during pregnancy or postpartum.
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Mastectomy for management of breast cancer in Ibadan, Nigeria.
BMC Surg
PUBLISHED: 05-13-2013
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Modified radical mastectomy remains the standard therapeutic surgical operation for breast cancer in most parts of the world. This retrospective study reviews mastectomy for management of breast cancer in a surgical oncology division over a ten year period.
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A meta-analysis identifies new loci associated with body mass index in individuals of African ancestry.
Keri L Monda, Gary K Chen, Kira C Taylor, Cameron Palmer, Todd L Edwards, Leslie A Lange, Maggie C Y Ng, Adebowale A Adeyemo, Matthew A Allison, Lawrence F Bielak, Guanjie Chen, Mariaelisa Graff, Marguerite R Irvin, Suhn K Rhie, Guo Li, Yongmei Liu, Youfang Liu, Yingchang Lu, Michael A Nalls, Yan V Sun, Mary K Wojczynski, Lisa R Yanek, Melinda C Aldrich, Adeyinka Ademola, Christopher I Amos, Elisa V Bandera, Cathryn H Bock, Angela Britton, Ulrich Broeckel, Quiyin Cai, Neil E Caporaso, Chris S Carlson, John Carpten, Graham Casey, Wei-Min Chen, Fang Chen, Yii-Der I Chen, Charleston W K Chiang, Gerhard A Coetzee, Ellen Demerath, Sandra L Deming-Halverson, Ryan W Driver, Patricia Dubbert, Mary F Feitosa, Ye Feng, Barry I Freedman, Elizabeth M Gillanders, Omri Gottesman, Xiuqing Guo, Talin Haritunians, Tamara Harris, Curtis C Harris, Anselm J M Hennis, Dena G Hernandez, Lorna H McNeill, Timothy D Howard, Barbara V Howard, Virginia J Howard, Karen C Johnson, Sun J Kang, Brendan J Keating, Suzanne Kolb, Lewis H Kuller, Abdullah Kutlar, Carl D Langefeld, Guillaume Lettre, Kurt Lohman, Vaneet Lotay, Helen Lyon, JoAnn E Manson, William Maixner, Yan A Meng, Kristine R Monroe, Imran Morhason-Bello, Adam B Murphy, Josyf C Mychaleckyj, Rajiv Nadukuru, Katherine L Nathanson, Uma Nayak, Amidou N'Diaye, Barbara Nemesure, Suh-Yuh Wu, M Cristina Leske, Christine Neslund-Dudas, Marian Neuhouser, Sarah Nyante, Heather Ochs-Balcom, Adesola Ogunniyi, Temidayo O Ogundiran, Oladosu Ojengbede, Olufunmilayo I Olopade, Julie R Palmer, Edward A Ruiz-Narváez, Nicholette D Palmer, Michael F Press, Evandine Rampersaud, Laura J Rasmussen-Torvik, Jorge L Rodriguez-Gil, Babatunde Salako, Eric E Schadt, Ann G Schwartz, Daniel A Shriner, David Siscovick, Shad B Smith, Sylvia Wassertheil-Smoller, Elizabeth K Speliotes, Margaret R Spitz, Lara Sucheston, Herman Taylor, Bamidele O Tayo, Margaret A Tucker, David J Van Den Berg, Digna R Velez Edwards, Zhaoming Wang, John K Wiencke, Thomas W Winkler, John S Witte, Margaret Wrensch, Xifeng Wu, James J Yang, Albert M Levin, Taylor R Young, Neil A Zakai, Mary Cushman, Krista A Zanetti, Jing Hua Zhao, Wei Zhao, Yonglan Zheng, Jie Zhou, Regina G Ziegler, Joseph M Zmuda, Jyotika K Fernandes, Gary S Gilkeson, Diane L Kamen, Kelly J Hunt, Ida J Spruill, Christine B Ambrosone, Stefan Ambs, Donna K Arnett, Larry Atwood, Diane M Becker, Sonja I Berndt, Leslie Bernstein, William J Blot, Ingrid B Borecki, Erwin P Bottinger, Donald W Bowden, Gregory Burke, Stephen J Chanock, Richard S Cooper, Jingzhong Ding, David Duggan, Michele K Evans, Caroline Fox, W Timothy Garvey, Jonathan P Bradfield, Hakon Hakonarson, Struan F A Grant, Ann Hsing, Lisa Chu, Jennifer J Hu, Dezheng Huo, Sue A Ingles, Esther M John, Joanne M Jordan, Edmond K Kabagambe, Sharon L R Kardia, Rick A Kittles, Phyllis J Goodman, Eric A Klein, Laurence N Kolonel, Loic Le Marchand, Simin Liu, Barbara McKnight, Robert C Millikan, Thomas H Mosley, Badri Padhukasahasram, L Keoki Williams, Sanjay R Patel, Ulrike Peters, Curtis A Pettaway, Patricia A Peyser, Bruce M Psaty, Susan Redline, Charles N Rotimi, Benjamin A Rybicki, Michèle M Sale, Pamela J Schreiner, Lisa B Signorello, Andrew B Singleton, Janet L Stanford, Sara S Strom, Michael J Thun, Mara Vitolins, Wei Zheng, Jason H Moore, Scott M Williams, Shamika Ketkar, Xiaofeng Zhu, Alan B Zonderman, , Charles Kooperberg, George J Papanicolaou, Brian E Henderson, Alex P Reiner, Joel N Hirschhorn, Ruth J F Loos, Kari E North, Christopher A Haiman.
Nat. Genet.
PUBLISHED: 03-18-2013
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Genome-wide association studies (GWAS) have identified 36 loci associated with body mass index (BMI), predominantly in populations of European ancestry. We conducted a meta-analysis to examine the association of >3.2 million SNPs with BMI in 39,144 men and women of African ancestry and followed up the most significant associations in an additional 32,268 individuals of African ancestry. We identified one new locus at 5q33 (GALNT10, rs7708584, P = 3.4 × 10(-11)) and another at 7p15 when we included data from the GIANT consortium (MIR148A-NFE2L3, rs10261878, P = 1.2 × 10(-10)). We also found suggestive evidence of an association at a third locus at 6q16 in the African-ancestry sample (KLHL32, rs974417, P = 6.9 × 10(-8)). Thirty-two of the 36 previously established BMI variants showed directionally consistent effect estimates in our GWAS (binomial P = 9.7 × 10(-7)), five of which reached genome-wide significance. These findings provide strong support for shared BMI loci across populations, as well as for the utility of studying ancestrally diverse populations.
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Fine mapping of breast cancer genome-wide association studies loci in women of African ancestry identifies novel susceptibility markers.
Carcinogenesis
PUBLISHED: 03-08-2013
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Numerous single nucleotide polymorphisms (SNPs) associated with breast cancer susceptibility have been identified by genome-wide association studies (GWAS). However, these SNPs were primarily discovered and validated in women of European and Asian ancestry. Because linkage disequilibrium is ancestry-dependent and heterogeneous among racial/ethnic populations, we evaluated common genetic variants at 22 GWAS-identified breast cancer susceptibility loci in a pooled sample of 1502 breast cancer cases and 1378 controls of African ancestry. None of the 22 GWAS index SNPs could be validated, challenging the direct generalizability of breast cancer risk variants identified in Caucasians or Asians to other populations. Novel breast cancer risk variants for women of African ancestry were identified in regions including 5p12 (odds ratio [OR] = 1.40, 95% confidence interval [CI] = 1.11-1.76; P = 0.004), 5q11.2 (OR = 1.22, 95% CI = 1.09-1.36; P = 0.00053) and 10p15.1 (OR = 1.22, 95% CI = 1.08-1.38; P = 0.0015). We also found positive association signals in three regions (6q25.1, 10q26.13 and 16q12.1-q12.2) previously confirmed by fine mapping in women of African ancestry. In addition, polygenic model indicated that eight best markers in this study, compared with 22 GWAS-identified SNPs, could better predict breast cancer risk in women of African ancestry (per-allele OR = 1.21, 95% CI = 1.16-1.27; P = 9.7 × 10(-16)). Our results demonstrate that fine mapping is a powerful approach to better characterize the breast cancer risk alleles in diverse populations. Future studies and new GWAS in women of African ancestry hold promise to discover additional variants for breast cancer susceptibility with clinical implications throughout the African diaspora.
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Development and pilot testing of an online module for ethics education based on the Nigerian National Code for Health Research Ethics.
BMC Med Ethics
PUBLISHED: 01-02-2013
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The formulation and implementation of national ethical regulations to protect research participants is fundamental to ethical conduct of research. Ethics education and capacity are inadequate in developing African countries. This study was designed to develop a module for online training in research ethics based on the Nigerian National Code of Health Research Ethics and assess its ease of use and reliability among biomedical researchers in Nigeria.
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Lack of association between common single nucleotide polymorphisms in the TERT-CLPTM1L locus and breast cancer in women of African ancestry.
Breast Cancer Res. Treat.
PUBLISHED: 11-16-2011
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As one of the most common cancers worldwide, breast cancer places an extraordinary burden on the populations of African ancestry. Common SNPs in the TERT-CLPTM1L locus have been reported to be associated with several types of cancer, including breast cancer. We sought to investigate whether the previously reported common single nucleotide polymorphisms (SNPs) in the TERT-CLPTM1L locus could also contribute to the breast cancer risk in women of African ancestry. We genotyped eleven SNPs in 2,892 women of African descent but were unable to detect any significant association between TERT-CLPTM1L SNPs and their predispositions for breast cancer risk. Given the differences in linkage disequilibrium patterns across populations, our findings suggest that larger independent studies from diverse populations are expected to evaluate the importance of the TERT-CLPTM1L locus in breast cancer.
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Gossypiboma: complete transmural migration of retained surgical sponge causing small bowel obstruction.
BMJ Case Rep
PUBLISHED: 01-01-2011
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The authors report a case of recurrent intestinal obstruction due to complete transmural migration of a retained surgical sponge into the small intestine. A 41-year-old woman presented with recurrent episodes of intestinal obstruction following a previous laparotomy in a private hospital for some gynaecologic procedures. Relaparotomy revealed a mass within the ileum which was resected and, when dissected out, was found to be a completely intraluminal retained surgical sponge. Although rare in daily practice, a retained intraperitoneal foreign body should be remotely considered in patients who present with new abdominal symptoms complex following a history of previous laparatomy.
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Surgeons opinions and practice of informed consent in Nigeria.
J Med Ethics
PUBLISHED: 10-12-2010
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Informed consent is perhaps more relevant to surgical specialties than to other clinical disciplines. Fundamental to this concept is the provision of relevant information for the patient to make an informed choice about a surgical intervention. The opinions of surgeons in Nigeria about informed consent in their practice were surveyed.
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Case-control study of body size and breast cancer risk in Nigerian women.
Am. J. Epidemiol.
PUBLISHED: 08-17-2010
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Previous studies have shown that weight is inversely associated with premenopausal breast cancer and positively associated with postmenopausal disease. Height has been shown to be positively correlated with breast cancer risk, but the association was not conclusive for premenopausal women. These previous studies were conducted primarily in Western countries, where height is not limited by nutritional status during childhood. The authors assessed the association between breast cancer and anthropometric measures in the Nigerian Breast Cancer Study (Ibadan, Nigeria). Between 1998 and 2009, 1,233 invasive breast cancer cases and 1,101 controls were recruited. The multivariate-adjusted odds ratio for the highest quartile group of height relative to the lowest was 2.03 (95% confidence interval (CI): 1.51, 2.72; P-trend < 0.001), with an odds ratio of 1.22 (95% CI: 1.14, 1.32) for each 5-cm increase, with no difference by menopausal status. Comparing women with a body mass index in the lowest quartile group, the adjusted odds ratio for women in the highest quartile category was 0.72 (95% CI: 0.54, 0.94; P-trend = 0.009) for premenopausal and postmenopausal women. Influence of height on breast cancer risk was quite strong in this cohort of indigenous Africans, which suggests that energy intake during childhood may be important in breast cancer development.
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Ancestry-shift refinement mapping of the C6orf97-ESR1 breast cancer susceptibility locus.
PLoS Genet.
PUBLISHED: 01-22-2010
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We used an approach that we term ancestry-shift refinement mapping to investigate an association, originally discovered in a GWAS of a Chinese population, between rs2046210[T] and breast cancer susceptibility. The locus is on 6q25.1 in proximity to the C6orf97 and estrogen receptor alpha (ESR1) genes. We identified a panel of SNPs that are correlated with rs2046210 in Chinese, but not necessarily so in other ancestral populations, and genotyped them in breast cancer case:control samples of Asian, European, and African origin, a total of 10,176 cases and 13,286 controls. We found that rs2046210[T] does not confer substantial risk of breast cancer in Europeans and Africans (OR = 1.04, P = 0.099, and OR = 0.98, P = 0.77, respectively). Rather, in those ancestries, an association signal arises from a group of less common SNPs typified by rs9397435. The rs9397435[G] allele was found to confer risk of breast cancer in European (OR = 1.15, P = 1.2 x 10(-3)), African (OR = 1.35, P = 0.014), and Asian (OR = 1.23, P = 2.9 x 10(-4)) population samples. Combined over all ancestries, the OR was 1.19 (P = 3.9 x 10(-7)), was without significant heterogeneity between ancestries (P(het) = 0.36) and the SNP fully accounted for the association signal in each ancestry. Haplotypes bearing rs9397435[G] are well tagged by rs2046210[T] only in Asians. The rs9397435[G] allele showed associations with both estrogen receptor positive and estrogen receptor negative breast cancer. Using early-draft data from the 1,000 Genomes project, we found that the risk allele of a novel SNP (rs77275268), which is closely correlated with rs9397435, disrupts a partially methylated CpG sequence within a known CTCF binding site. These studies demonstrate that shifting the analysis among ancestral populations can provide valuable resolution in association mapping.
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Evidence for an ancient BRCA1 mutation in breast cancer patients of Yoruban ancestry.
Fam. Cancer
PUBLISHED: 05-01-2009
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BRCA1 recurrent mutations have rarely been assessed in non-founder populations. Still, identifying such mutations could be important for designing genetic testing strategies for high-risk breast/ovarian cancer families in non-founder populations.
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A genome-wide association study of breast cancer in women of African ancestry.
Hum. Genet.
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Genome-wide association studies (GWAS) in diverse populations are needed to reveal variants that are more common and/or limited to defined populations. We conducted a GWAS of breast cancer in women of African ancestry, with genotyping of >1,000,000 SNPs in 3,153 African American cases and 2,831 controls, and replication testing of the top 66 associations in an additional 3,607 breast cancer cases and 11,330 controls of African ancestry. Two of the 66 SNPs replicated (p < 0.05) in stage 2, which reached statistical significance levels of 10(-6) and 10(-5) in the stage 1 and 2 combined analysis (rs4322600 at chromosome 14q31: OR = 1.18, p = 4.3 × 10(-6); rs10510333 at chromosome 3p26: OR = 1.15, p = 1.5 × 10(-5)). These suggestive risk loci have not been identified in previous GWAS in other populations and will need to be examined in additional samples. Identification of novel risk variants for breast cancer in women of African ancestry will demand testing of a substantially larger set of markers from stage 1 in a larger replication sample.
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Recurrent BRCA1 and BRCA2 mutations in breast cancer patients of African ancestry.
Breast Cancer Res. Treat.
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Recurrent mutations constituted nearly three quarters of all BRCA1 mutations and almost half of all BRCA2 mutations identified in the first cohort of the Nigerian Breast Cancer Study. To further characterize breast/ovarian cancer risks associated with BRCA1/BRCA2 mutations in the African diaspora, we genotyped recurrent mutations among Nigerian, African American, and Barbadian breast cancer patients. A replication cohort of 356 Nigerian breast cancer patients was genotyped for 12 recurrent BRCA1/2 mutant alleles (Y101X, 1742insG, 4241delTG, M1775R, 4359insC, C64Y, 1623delTTAAA, Q1090X, and 943ins10 from BRCA1, and 1538delAAGA, 2630del11, and 9045delGAAA from BRCA2) by means of SNaPshot followed by direct sequencing or by direct sequencing alone. In addition, 260 African Americans and 118 Barbadians were genotyped for six of the recurrent BRCA1 mutations by SNaPshot assay. Of all the BRCA1/2 recurrent mutations we identified in the first cohort, six were identified in 11 patients in the replication study. These mutation carriers constitute 3.1 % [95 % Confidence Interval (CI) 1.6-5.5 %] of the replication cohort. By comparison, 6.9 % (95 % CI 4.7-9.7 %) of the discovery cohort carried BRCA1/2 recurrent mutations. For the subset of recurrent mutations we tested in breast cancer cases from Barbados or the United States, only two 943ins10 carriers were identified in African Americans. Nigerian breast cancer patients from Ibadan carry a broad and unique spectrum of BRCA1/2 mutations. Our data suggest that BRCA1/2 mutation testing limited to recurrent mutations is not sufficient to understand the BRCA1/2-associated breast cancer risk in African populations in the diaspora. As the cost of Sanger sequencing is considerably reduced, deploying innovative technologies such as high throughput DNA sequencing of BRCA1/2 and other cancer susceptibility genes will be essential for identifying high-risk individuals and families to reduce the burden of aggressive early onset breast cancer in low-resource settings.
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Body fat distribution and breast cancer risk: findings from the Nigerian breast cancer study.
Cancer Causes Control
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The relationship between overall obesity and breast cancer risk has been well recognized, but the role of central obesity in breast cancer development is uncertain.
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Evaluation of 19 susceptibility loci of breast cancer in women of African ancestry.
Carcinogenesis
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Multiple breast cancer susceptibility loci have been identified in genome-wide association studies (GWAS) in populations of European and Asian ancestry using array chips optimized for populations of European ancestry. It is important to examine whether these loci are associated with breast cancer risk in women of African ancestry. We evaluated 25 single nucleotide polymorphisms (SNPs) at 19 loci in a pooled case-control study of breast cancer, which included 1509 cases and 1383 controls. Cases and controls were enrolled in Nigeria, Barbados and the USA; all women were of African ancestry. We found significant associations for three SNPs, which were in the same direction and of similar magnitude as those reported in previous fine-mapping studies in women of African ancestry. The allelic odds ratios were 1.24 [95% confidence interval (CI): 1.04-1.47; P = 0.018] for the rs2981578-G allele (10q26/FGFR2), 1.34 (95% CI: 1.10-1.63; P = 0.0035) for the rs9397435-G allele (6q25) and 1.12 (95% CI: 1.00-1.25; P = 0.04) for the rs3104793-C allele (16q12). Although a significant association was observed for an additional index SNP (rs3817198), it was in the opposite direction to prior GWAS studies. In conclusion, this study highlights the complexity of applying current GWAS findings across racial/ethnic groups, as none of GWAS-identified index SNPs could be replicated in women of African ancestry. Further fine-mapping studies in women of African ancestry will be needed to reveal additional and causal variants for breast cancer.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.