Pub Date : 2015-03-31DOI: 10.26443/msurj.v10i1.117
B. Niraula, J. Nadeau
Background: Tracking of microbial organisms over a volume requires images at multiple focal planes along the orthogonal direction. With most conventional microscopes, this requires repeated readjustments; using Digital Holographic Microscopy (DHM), it is possible to use a set of interference patterns to reconstruct at various distances, thereby creating a 3D stack based off a single image. Methods: We used an off-axis Mach-Zehnder DHM for imaging and tracking bacterial movement. We describe the algorithm employed for tracking, as well as our improvement of trackability by testing differences in image contrast with the use of Quantum Dots. Results: We show that the use of Quantum Dots resulted in an increase in contrast of approximately 11%. Conclusion: We suggest this as a method of increasing resolvability of individual microbes. With a more compact design, the microscope will be applicable in various fields, and can be used remotely for studies of microbial organisms.
{"title":"Optimisation of a Holographic Microscope for Microbial Study","authors":"B. Niraula, J. Nadeau","doi":"10.26443/msurj.v10i1.117","DOIUrl":"https://doi.org/10.26443/msurj.v10i1.117","url":null,"abstract":"\u0000 \u0000 \u0000 \u0000Background: Tracking of microbial organisms over a volume requires images at multiple focal planes along the orthogonal direction. With most conventional microscopes, this requires repeated readjustments; using Digital Holographic Microscopy (DHM), it is possible to use a set of interference patterns to reconstruct at various distances, thereby creating a 3D stack based off a single image. \u0000Methods: We used an off-axis Mach-Zehnder DHM for imaging and tracking bacterial movement. We describe the algorithm employed for tracking, as well as our improvement of trackability by testing differences in image contrast with the use of Quantum Dots. \u0000Results: We show that the use of Quantum Dots resulted in an increase in contrast of approximately 11%. \u0000Conclusion: We suggest this as a method of increasing resolvability of individual microbes. With a more compact design, the microscope will be applicable in various fields, and can be used remotely for studies of microbial organisms. \u0000 \u0000 \u0000 \u0000","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69323260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-31DOI: 10.26443/msurj.v10i1.123
Daniel M. Sapozhnikov
Background: Alzheimer’s disease (AD) is a neurodegenerative disorder that affects 5 million United States citizens. Many authors have proposed that mindfulness-based interventions (MBIs) have the potential to effectively prevent AD-associated pathology and symptomology. However, the fact that both meditation and AD are complex processes that involve a great number of biological pathways has made these phenomena particularly challenging to dissect. This review advocates the use of gene expression to investigate the mechanisms by which MBIs combat AD pathology. Methods: Searches were performed using Thomson Reuters Web of Science. Ultimately, 85 journal articles were selected for their content as it pertains to the purpose of this review. Summary: Peripheral blood mononuclear cells (PBMCs) may provide reliable measures of cerebral gene expression. Profiling their gene expression has demonstrated that MBIs may produce gene expression changes in many of the same pathways (inflammation, cellular stress, proliferation, synaptic function) and often in the opposite direction of disease-related deregulation. While AD is marked by shortened telomeres resulting in genetic turmoil, meditation has been documented to exhibit a positive effect on telomere maintenance. A comprehensive gene expression investigation is invaluable to reveal relevant molecular mechanisms and provide the foundation for exploring the interaction between MBI and AD.
背景:阿尔茨海默病(AD)是一种神经退行性疾病，影响着500万美国公民。许多作者提出，正念干预(MBIs)具有有效预防ad相关病理和症状的潜力。然而，冥想和AD都是复杂的过程，涉及大量的生物途径，这使得这些现象特别具有挑战性。这篇综述提倡使用基因表达来研究mbi对抗AD病理的机制。方法:使用Thomson Reuters Web of Science进行检索。最终，85篇期刊文章被选中，因为它们的内容与本综述的目的有关。摘要:外周血单个核细胞(PBMCs)可以提供可靠的大脑基因表达指标。对其基因表达的分析表明，mbi可能在许多相同的途径(炎症、细胞应激、增殖、突触功能)中产生基因表达变化，并且通常与疾病相关的解除管制的方向相反。虽然阿尔茨海默病的特点是端粒缩短，导致基因混乱，但冥想对端粒的维持有积极的影响。全面的基因表达研究对于揭示相关分子机制，为探索MBI与AD的相互作用奠定基础具有重要意义。
{"title":"Promise of Mindfulness-Based Interventions as Therapies to Prevent Cognitive Decline","authors":"Daniel M. Sapozhnikov","doi":"10.26443/msurj.v10i1.123","DOIUrl":"https://doi.org/10.26443/msurj.v10i1.123","url":null,"abstract":"\u0000 \u0000 \u0000 \u0000Background: Alzheimer’s disease (AD) is a neurodegenerative disorder that affects 5 million United States citizens. Many authors have proposed that mindfulness-based interventions (MBIs) have the potential to effectively prevent AD-associated pathology and symptomology. However, the fact that both meditation and AD are complex processes that involve a great number of biological pathways has made these phenomena particularly challenging to dissect. This review advocates the use of gene expression to investigate the mechanisms by which MBIs combat AD pathology. \u0000Methods: Searches were performed using Thomson Reuters Web of Science. Ultimately, 85 journal articles were selected for their content as it pertains to the purpose of this review. \u0000Summary: Peripheral blood mononuclear cells (PBMCs) may provide reliable measures of cerebral gene expression. Profiling their gene expression has demonstrated that MBIs may produce gene expression changes in many of the same pathways (inflammation, cellular stress, proliferation, synaptic function) and often in the opposite direction of disease-related deregulation. While AD is marked by shortened telomeres resulting in genetic turmoil, meditation has been documented to exhibit a positive effect on telomere maintenance. A comprehensive gene expression investigation is invaluable to reveal relevant molecular mechanisms and provide the foundation for exploring the interaction between MBI and AD. \u0000 \u0000 \u0000 \u0000","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69323371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-31DOI: 10.26443/msurj.v10i1.115
Jacqueline Riddle, J. Bayne, I. Butler
Background: The three cadmium(II) chalcogenides CdX (X = S, Se, Te; Cadmium with either Sulphur, Se- lenium, or Tellurium), have important applications as artists’ pigments and in the electronics industry. The purpose of this study is to assess the structural stabilities of bulk, microcrystalline samples of the three cadmium(II) chalcogenides over a wide temperature range by examining the changes that occur in their Raman spectra. Methods: We recorded the Raman spectra of the three cadmium(II) chalcogenides from -196 °C to 500 °C on a commercial instrument equipped with a microscope and a variable-temperature stage. Results: While the Raman spectra of all three cadmium(II) chalcogenides exhibited significant peak shifts and broadening with increasing temperature, these effects were completely reversible. There is no evidence of phase transitions, indicating structural stability. Conclusion: Taken together, our results show that the three cadmium(II) chalcogenides are resistant to structural changes throughout the almost -700 °C temperature range investigated, thereby reinforcing their continued use in artwork and in the electronics industry.
背景:三种镉(II)硫属化合物CdX (X = S, Se, Te;镉(含硫、硒或碲)作为艺术家的颜料和电子工业有重要的应用。本研究的目的是通过检查三种镉(II)硫族化合物的拉曼光谱变化，评估其体微晶样品在宽温度范围内的结构稳定性。方法:在配有显微镜和变温台的商用仪器上记录3种镉(II)硫族化合物在-196 ~ 500℃范围内的拉曼光谱。结果:虽然三种镉硫族化合物的拉曼光谱随温度的升高均表现出明显的峰移和展宽，但这些影响是完全可逆的。没有相变的证据，表明结构稳定。综上所述，我们的研究结果表明，三种镉(II)硫族化合物在几乎-700°C的温度范围内都能抵抗结构变化，从而加强了它们在艺术品和电子工业中的继续使用。
{"title":"Cadmium(II) Chalcogenides Stable across Wide Temperature Range","authors":"Jacqueline Riddle, J. Bayne, I. Butler","doi":"10.26443/msurj.v10i1.115","DOIUrl":"https://doi.org/10.26443/msurj.v10i1.115","url":null,"abstract":"\u0000 \u0000 \u0000 \u0000Background: The three cadmium(II) chalcogenides CdX (X = S, Se, Te; Cadmium with either Sulphur, Se- lenium, or Tellurium), have important applications as artists’ pigments and in the electronics industry. The purpose of this study is to assess the structural stabilities of bulk, microcrystalline samples of the three cadmium(II) chalcogenides over a wide temperature range by examining the changes that occur in their Raman spectra. \u0000 \u0000 \u0000 \u0000 \u0000Methods: We recorded the Raman spectra of the three cadmium(II) chalcogenides from -196 °C to 500 °C on a commercial instrument equipped with a microscope and a variable-temperature stage. \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000Results: While the Raman spectra of all three cadmium(II) chalcogenides exhibited significant peak shifts and broadening with increasing temperature, these effects were completely reversible. There is no evidence of phase transitions, indicating structural stability. \u0000Conclusion: Taken together, our results show that the three cadmium(II) chalcogenides are resistant to structural changes throughout the almost -700 °C temperature range investigated, thereby reinforcing their continued use in artwork and in the electronics industry. \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000 \u0000","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69323244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-31DOI: 10.26443/msurj.v10i1.116
Jean-Franois Blanchette, Yi Huang
Background: Since 1997-98, observations of annual mean surface temperature have shown a slowdown of global temperature increases, suggesting a hiatus in global warming. Given this finding, we are interested in diagnosing trends in the Earth’s outgoing longwave radiation (OLR) spectrum throughout the last decade. Methods: We calculated the trend in OLR measured by the Atmospheric Infrared Sounder (AIRS) aboard NASA’s Aqua satellite between 2003 and 2013, and compared these results with the trend in atmospheric and surface temperature and tropospheric absolute humidity, obtained from AIRS retrieval product and from the ECMWF (European Center for Medium range Weather Forecasting) Re-Analysis (ERA) interim product. We also isolated the greenhouse effect from the OLR trend by subtracting the amount of surface radiation emitted from the total radiation received by the sounder. Results: The OLR trend is negative in the CO2 absorption band, negative in the window spectral region, and positive in the water vapor band. The trend in surface and tropospheric temperature is negative, as is the trend in tropospheric absolute humidity. The greenhouse effect is increasing in the CO2 band, generally slightly increasing in the window region, and decreasing in the H2O band. Conclusion: Our results show that the CO2 forcing was still present globally through the last decade, with steadily increasing effects. Contributors to the negative trend in OLR in the window region are a small decrease in surface temperature and a strong decrease in tropospheric temperature, where tropospheric H2O emit radiation to space. The decreasing effect of water vapor in the H2O band is due to decreasing tropospheric humidity. This analysis will allow us to detect the changes in greenhouse gas forcing, to examine the correlated surface temperature response, and to study changes and effects in tropospheric water vapor concentration.
{"title":"Earth Infrared Radiation Spectra During Global Warming Hiatus","authors":"Jean-Franois Blanchette, Yi Huang","doi":"10.26443/msurj.v10i1.116","DOIUrl":"https://doi.org/10.26443/msurj.v10i1.116","url":null,"abstract":"\u0000 \u0000 \u0000 \u0000Background: Since 1997-98, observations of annual mean surface temperature have shown a slowdown of global temperature increases, suggesting a hiatus in global warming. Given this finding, we are interested in diagnosing trends in the Earth’s outgoing longwave radiation (OLR) spectrum throughout the last decade. \u0000Methods: We calculated the trend in OLR measured by the Atmospheric Infrared Sounder (AIRS) aboard NASA’s Aqua satellite between 2003 and 2013, and compared these results with the trend in atmospheric and surface temperature and tropospheric absolute humidity, obtained from AIRS retrieval product and from the ECMWF (European Center for Medium range Weather Forecasting) Re-Analysis (ERA) interim product. We also isolated the greenhouse effect from the OLR trend by subtracting the amount of surface radiation emitted from the total radiation received by the sounder. \u0000Results: The OLR trend is negative in the CO2 absorption band, negative in the window spectral region, and positive in the water vapor band. The trend in surface and tropospheric temperature is negative, as is the trend in tropospheric absolute humidity. The greenhouse effect is increasing in the CO2 band, generally slightly increasing in the window region, and decreasing in the H2O band. \u0000 \u0000 \u0000 \u0000 \u0000Conclusion: Our results show that the CO2 forcing was still present globally through the last decade, with steadily increasing effects. Contributors to the negative trend in OLR in the window region are a small decrease in surface temperature and a strong decrease in tropospheric temperature, where tropospheric H2O emit radiation to space. The decreasing effect of water vapor in the H2O band is due to decreasing tropospheric humidity. This analysis will allow us to detect the changes in greenhouse gas forcing, to examine the correlated surface temperature response, and to study changes and effects in tropospheric water vapor concentration. \u0000 \u0000 \u0000 \u0000","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69323258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-31DOI: 10.26443/msurj.v10i1.122
Bridget Hovendon, Michelle Kaufman
Background: Dementia is a neurocognitive disorder that involves multiple cognitive deficits, including memory impairment. Dementia occurs in a variety of disease processes, including Alzheimer disease (AD) and dementia with Lewy bodies, the two most prevalent neurocognitive diseases. This paper reviews the signs and symptoms, neuropathology, diagnosis, prognosis, and treatment of Dementia with Lewy bodies (DLB). Methods: Terms searched included “Lewy body dementia,” “Lewy body disease,” “cognitive disorders,” and “neurodegenerative diseases.” Priority was given to peer-reviewed sources published within the last five years. Summary: In addition to standard neurocognitive disorder symptoms, patients with DLB present clinically fluctuating cognition, visual hallucinations, and Parkinsonism as well as a variety of other symptoms with lower diagnostic sensitivity. Clinical signs, cognitive assessments, and radiologic imaging are used to diagnose DLB as being distinct from disorders like AD, Parkinson disease dementia (PDD), delirium, and normal aging changes. Interventions for this disease may be pharmacological or non-pharmacological. Pharmacological treatments include cholinesterase inhibitors, Levadopa, and selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors. Non-pharmacological interventions include occupational therapy, cognitive stimulation, and physical activity.
{"title":"Dementia With Lewy Bodies: An Overview","authors":"Bridget Hovendon, Michelle Kaufman","doi":"10.26443/msurj.v10i1.122","DOIUrl":"https://doi.org/10.26443/msurj.v10i1.122","url":null,"abstract":"\u0000 \u0000 \u0000 \u0000Background: Dementia is a neurocognitive disorder that involves multiple cognitive deficits, including memory impairment. Dementia occurs in a variety of disease processes, including Alzheimer disease (AD) and dementia with Lewy bodies, the two most prevalent neurocognitive diseases. This paper reviews the signs and symptoms, neuropathology, diagnosis, prognosis, and treatment of Dementia with Lewy bodies (DLB). \u0000Methods: Terms searched included “Lewy body dementia,” “Lewy body disease,” “cognitive disorders,” and “neurodegenerative diseases.” Priority was given to peer-reviewed sources published within the last five years. \u0000Summary: In addition to standard neurocognitive disorder symptoms, patients with DLB present clinically fluctuating cognition, visual hallucinations, and Parkinsonism as well as a variety of other symptoms with lower diagnostic sensitivity. Clinical signs, cognitive assessments, and radiologic imaging are used to diagnose DLB as being distinct from disorders like AD, Parkinson disease dementia (PDD), delirium, and normal aging changes. Interventions for this disease may be pharmacological or non-pharmacological. Pharmacological treatments include cholinesterase inhibitors, Levadopa, and selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors. Non-pharmacological interventions include occupational therapy, cognitive stimulation, and physical activity. \u0000 \u0000 \u0000 \u0000","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69323309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-31DOI: 10.26443/msurj.v10i1.118
H. Su, J. Dent
Background: Ivermectin is a widely used anti-parasitic drug that binds to and activates glutamate-gated chloride channels (GluCls), giving it its nematocidal (nematode-killing) properties. Due to excessive use of ivermectin, frequent cases of resistance to this nematicide are being reported, suggesting that ivermectin is beginning to lose its efficacy. This project seeks to study whether a mutation of the glc-2 gene, which encodes for a β subunit of the GluCl channel, confers ivermectin resistance. We hypothesize that a glc-2 mutation achieves nematicide resistance by creating a defective GluCl channel that cannot bind to ivermectin. Methods: We used classical genetics to obtain the desired mutants from stock worms. We then tested the worms for resistance profile using ivermectin sensitivity assays. Finally, we examined in vivo interactions by expressing relevant RNA in a heterologous system and performed electrophysiological recordings. Results: We were able to demonstrate that presence of the defective glc-2 leads to increased resistance profiles when given the chance to associate with select GluClα subunits (e.g. AVR-15). We also demonstrated that co-injection of glc-2 and glc-3 compromises GluCl response to L-glutamate, a critical indicator of channel functionality. Conclusion: Our results lend strong support to our hypothesis that glc-2 is able to interact with certain α subunits of GluCl to confer ivermectin resistance. This finding provides a framework for future dominant ivermectin resistance studies.
{"title":"Mutation of the Glc-2 Gene May Confer Dominant Ivermectin Resistance","authors":"H. Su, J. Dent","doi":"10.26443/msurj.v10i1.118","DOIUrl":"https://doi.org/10.26443/msurj.v10i1.118","url":null,"abstract":"\u0000 \u0000 \u0000 \u0000Background: Ivermectin is a widely used anti-parasitic drug that binds to and activates glutamate-gated chloride channels (GluCls), giving it its nematocidal (nematode-killing) properties. Due to excessive use of ivermectin, frequent cases of resistance to this nematicide are being reported, suggesting that ivermectin is beginning to lose its efficacy. This project seeks to study whether a mutation of the glc-2 gene, which encodes for a β subunit of the GluCl channel, confers ivermectin resistance. We hypothesize that a glc-2 mutation achieves nematicide resistance by creating a defective GluCl channel that cannot bind to ivermectin. \u0000Methods: We used classical genetics to obtain the desired mutants from stock worms. We then tested the worms for resistance profile using ivermectin sensitivity assays. Finally, we examined in vivo interactions by expressing relevant RNA in a heterologous system and performed electrophysiological recordings. \u0000Results: We were able to demonstrate that presence of the defective glc-2 leads to increased resistance profiles when given the chance to associate with select GluClα subunits (e.g. AVR-15). We also demonstrated that co-injection of glc-2 and glc-3 compromises GluCl response to L-glutamate, a critical indicator of channel functionality. \u0000Conclusion: Our results lend strong support to our hypothesis that glc-2 is able to interact with certain α subunits of GluCl to confer ivermectin resistance. This finding provides a framework for future dominant ivermectin resistance studies. \u0000 \u0000 \u0000 \u0000","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69323266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-01DOI: 10.26443/msurj.v10i1.120
Justin Graffi, E. Moss, Alexia Jolicoeur-Martineau, Gal Moss, V. Lecompte, Katherine Pascuzzo, Vanessa Babineau, Cathryn Gordon-Green, Viara R. Mileva‐Seitz, K. Minde, R. Sassi, N. Carrey, J. Kennedy, H. Gaudreau, R. Levitan, M. Meaney, A. Wazana
BACKGROUND The current paper aimed to explore the effects of birth weight and the 7-repeat allele in Exon III of the dopamine D4 receptor (DRD4) gene on the development of disorganized attachment, a potential endophenotype of depression. Infants born with low birth weight have been shown to be at higher risk for later neurological impairments, psychological disorders or behavioural problems. The DRD4 gene is critical for the cognitive and emotional processes that are sub-served by neural circuits in the prefrontal cortex. This paper examined the main effect of birth weight and DRD4 on the development of disorganized attachment. METHODS Data was used from the Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) project. The sample consisted of 251 mother-child dyads with complete data. Attachment style was assessed using the modified separation-reunion procedure. RESULTS There was no main effect for birth weight on disorganized attachment, (b = -0.001, p = 0.998). There was, however, a main effect for the DRD4 7-repeat polymorphism on disorganized attachment (b = -1.120, p = 0.004). LIMITATIONS Compared to studies of similar design, the sample size in this study was relatively small. Additionally, a significant number of subjects did not have complete data. CONCLUSIONS Children without the DRD4 7-repeat allele were more likely to have disorganized attachment than children with the DRD4 7-repeat allele. This indicates that the 7-repeate allele of the DRD4 gene may actually serve as a protective factor against disorganized attachment.
背景本研究旨在探讨出生体重和多巴胺D4受体(DRD4)基因外显子III上7重复等位基因对无序依恋(一种潜在的抑郁症内表型)发展的影响。研究表明，出生时体重过轻的婴儿日后出现神经损伤、心理障碍或行为问题的风险更高。DRD4基因对认知和情感过程至关重要，这些过程由前额皮质的神经回路次级服务。本研究探讨了出生体重和DRD4对无组织依恋发展的主要影响。方法数据来源于母体逆境、脆弱性和神经发育(MAVAN)项目。样本由251对数据完整的母子二人组组成。采用改进的分离-团聚程序评估依恋类型。结果出生体重对无组织依恋无主要影响(b = -0.001, p = 0.998)。然而，DRD4 7-repeat多态性对无组织依恋有主要影响(b = -1.120, p = 0.004)。局限性与类似设计的研究相比，本研究的样本量相对较小。此外，相当数量的受试者没有完整的数据。结论不携带DRD4 7-repeat等位基因的儿童比携带DRD4 7-repeat等位基因的儿童更易发生无组织依恋。这表明DRD4基因的7重复等位基因实际上可能是防止无组织附着的保护因子。
{"title":"Preschool children without 7-repeat DRD4 gene more likely to develop disorganized attachment style.","authors":"Justin Graffi, E. Moss, Alexia Jolicoeur-Martineau, Gal Moss, V. Lecompte, Katherine Pascuzzo, Vanessa Babineau, Cathryn Gordon-Green, Viara R. Mileva‐Seitz, K. Minde, R. Sassi, N. Carrey, J. Kennedy, H. Gaudreau, R. Levitan, M. Meaney, A. Wazana","doi":"10.26443/msurj.v10i1.120","DOIUrl":"https://doi.org/10.26443/msurj.v10i1.120","url":null,"abstract":"BACKGROUND The current paper aimed to explore the effects of birth weight and the 7-repeat allele in Exon III of the dopamine D4 receptor (DRD4) gene on the development of disorganized attachment, a potential endophenotype of depression. Infants born with low birth weight have been shown to be at higher risk for later neurological impairments, psychological disorders or behavioural problems. The DRD4 gene is critical for the cognitive and emotional processes that are sub-served by neural circuits in the prefrontal cortex. This paper examined the main effect of birth weight and DRD4 on the development of disorganized attachment. METHODS Data was used from the Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) project. The sample consisted of 251 mother-child dyads with complete data. Attachment style was assessed using the modified separation-reunion procedure. RESULTS There was no main effect for birth weight on disorganized attachment, (b = -0.001, p = 0.998). There was, however, a main effect for the DRD4 7-repeat polymorphism on disorganized attachment (b = -1.120, p = 0.004). LIMITATIONS Compared to studies of similar design, the sample size in this study was relatively small. Additionally, a significant number of subjects did not have complete data. CONCLUSIONS Children without the DRD4 7-repeat allele were more likely to have disorganized attachment than children with the DRD4 7-repeat allele. This indicates that the 7-repeate allele of the DRD4 gene may actually serve as a protective factor against disorganized attachment.","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88850088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Justin Graffi, Ellen Moss, Alexia Jolicoeur-Martineau, Gal Moss, Vanessa Lecompte, Katherine Pascuzzo, Vanessa Babineau, Cathryn Gordon-Green, Viara R Mileva-Seitz, Klaus Minde, Roberto Sassi, Normand Carrey, James L Kennedy, Helene Gaudreau, Robert Levitan, Michael Meaney, Ashley Wazana
Background: The current paper aimed to explore the effects of birth weight and the 7-repeat allele in Exon III of the dopamine D4 receptor (DRD4) gene on the development of disorganized attachment, a potential endophenotype of depression. Infants born with low birth weight have been shown to be at higher risk for later neurological impairments, psychological disorders or behavioural problems. The DRD4 gene is critical for the cognitive and emotional processes that are sub-served by neural circuits in the prefrontal cortex. This paper examined the main effect of birth weight and DRD4 on the development of disorganized attachment.
Methods: Data was used from the Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) project. The sample consisted of 251 mother-child dyads with complete data. Attachment style was assessed using the modified separation-reunion procedure.
Results: There was no main effect for birth weight on disorganized attachment, (b = -0.001, p = 0.998). There was, however, a main effect for the DRD4 7-repeat polymorphism on disorganized attachment (b = -1.120, p = 0.004).
Limitations: Compared to studies of similar design, the sample size in this study was relatively small. Additionally, a significant number of subjects did not have complete data.
Conclusions: Children without the DRD4 7-repeat allele were more likely to have disorganized attachment than children with the DRD4 7-repeat allele. This indicates that the 7-repeate allele of the DRD4 gene may actually serve as a protective factor against disorganized attachment.
背景:本研究旨在探讨出生体重和多巴胺D4受体(DRD4)基因外显子III中7重复等位基因对无序依恋(一种潜在的抑郁症内表型)发展的影响。研究表明，出生时体重过轻的婴儿日后出现神经损伤、心理障碍或行为问题的风险更高。DRD4基因对认知和情感过程至关重要，这些过程由前额皮质的神经回路次级服务。本研究探讨了出生体重和DRD4对无组织依恋发展的主要影响。方法:数据来源于母体逆境、脆弱性和神经发育(MAVAN)项目。样本由251对数据完整的母子二人组组成。采用改进的分离-团聚程序评估依恋类型。结果:出生体重对无组织依恋无主要影响(b = -0.001, p = 0.998)。然而，DRD4 7-repeat多态性对无组织依恋有主要影响(b = -1.120, p = 0.004)。局限性:与类似设计的研究相比，本研究的样本量相对较小。此外，相当数量的受试者没有完整的数据。结论:无DRD4 7-repeat等位基因的儿童比有DRD4 7-repeat等位基因的儿童更容易出现无组织依恋。这表明DRD4基因的7重复等位基因实际上可能是防止无组织附着的保护因子。
{"title":"Preschool children without 7-repeat DRD4 gene more likely to develop disorganized attachment style.","authors":"Justin Graffi, Ellen Moss, Alexia Jolicoeur-Martineau, Gal Moss, Vanessa Lecompte, Katherine Pascuzzo, Vanessa Babineau, Cathryn Gordon-Green, Viara R Mileva-Seitz, Klaus Minde, Roberto Sassi, Normand Carrey, James L Kennedy, Helene Gaudreau, Robert Levitan, Michael Meaney, Ashley Wazana","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Background: </strong>The current paper aimed to explore the effects of birth weight and the 7-repeat allele in Exon III of the dopamine D4 receptor (DRD4) gene on the development of disorganized attachment, a potential endophenotype of depression. Infants born with low birth weight have been shown to be at higher risk for later neurological impairments, psychological disorders or behavioural problems. The DRD4 gene is critical for the cognitive and emotional processes that are sub-served by neural circuits in the prefrontal cortex. This paper examined the main effect of birth weight and DRD4 on the development of disorganized attachment.</p><p><strong>Methods: </strong>Data was used from the Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) project. The sample consisted of 251 mother-child dyads with complete data. Attachment style was assessed using the modified separation-reunion procedure.</p><p><strong>Results: </strong>There was no main effect for birth weight on disorganized attachment, (b = -0.001, <i>p</i> = 0.998). There was, however, a main effect for the DRD4 7-repeat polymorphism on disorganized attachment (b = -1.120, <i>p</i> = 0.004).</p><p><strong>Limitations: </strong>Compared to studies of similar design, the sample size in this study was relatively small. Additionally, a significant number of subjects did not have complete data.</p><p><strong>Conclusions: </strong>Children without the DRD4 7-repeat allele were more likely to have disorganized attachment than children with the DRD4 7-repeat allele. This indicates that the 7-repeate allele of the DRD4 gene may actually serve as a protective factor against disorganized attachment.</p>","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5447455/pdf/nihms6634.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35055150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: In the past, much of the scientific research on microbes focused on mechanisms of infection and disease. This was not in vain, as we gained valuable knowledge about our immune system, as well as the ability to develop vaccines and antibiotics. However, the relationship between humans and microbes is complex. These species have been co-evolving since multicellular organisms evolved on Earth. Summary: Recently, it is beginning to be appreciated that the majority of relationships between humans and microbes are beneficial. From this follows an understanding that beneficial microbes are vital to the normal physiological development of our gut and immune system. This beneficial relationship between the human host and the multitude of microbial communities is well established. However, currently in the developed world epidemiological studies are showing dramatic increases in autoimmunity, allergies, and obesity. It is thus suggested that within westernized societies hygiene is altering the relationship between the gut and the human host in a way that makes humans susceptible to conditions not seen in less developed countries. This understanding advanced the “hygiene hypothesis,” and more recently the, “old friends hypothesis” and “disappearing microbiota hypothesis” as possible explanations for the observed epidemiological phenomena. What follows is a review of the relationship between gut microbes and the host’s immune system, with a focus on how hygiene (antibiotics, chlorination of water, etc.) is beginning to alter this relationship. This review concludes that a further understanding of how hygiene affects the relationship between humans and microbes will be crucial for developing effective therapies considerate of our microbial friends.
{"title":"Human Health and the Microbiota: Interactions Between Gut Microbes, Hygiene, and The Immune System","authors":"S. Fukada","doi":"10.26443/msurj.v9i1.161","DOIUrl":"https://doi.org/10.26443/msurj.v9i1.161","url":null,"abstract":"Background: In the past, much of the scientific research on microbes focused on mechanisms of infection and disease. This was not in vain, as we gained valuable knowledge about our immune system, as well as the ability to develop vaccines and antibiotics. However, the relationship between humans and microbes is complex. These species have been co-evolving since multicellular organisms evolved on Earth. \u0000Summary: Recently, it is beginning to be appreciated that the majority of relationships between humans and microbes are beneficial. From this follows an understanding that beneficial microbes are vital to the normal physiological development of our gut and immune system. This beneficial relationship between the human host and the multitude of microbial communities is well established. However, currently in the developed world epidemiological studies are showing dramatic increases in autoimmunity, allergies, and obesity. It is thus suggested that within westernized societies hygiene is altering the relationship between the gut and the human host in a way that makes humans susceptible to conditions not seen in less developed countries. This understanding advanced the “hygiene hypothesis,” and more recently the, “old friends hypothesis” and “disappearing microbiota hypothesis” as possible explanations for the observed epidemiological phenomena. What follows is a review of the relationship between gut microbes and the host’s immune system, with a focus on how hygiene (antibiotics, chlorination of water, etc.) is beginning to alter this relationship. This review concludes that a further understanding of how hygiene affects the relationship between humans and microbes will be crucial for developing effective therapies considerate of our microbial friends.","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69325609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: B-Raf is one of the earliest and most common genetic mutations observed in many different types of cancers. A single mutation in B-Raf cannot cause full-blown cancer, but may cause an observed phenotype called oncogene induced senescence (OIS). This suggests the need for cooperation between B-Raf and other genes for successful tumorigenesis. Objective: We look to characterize Human Fibroblast cells that are able to senesce in response to elevated oncogenic expression of B-Raf. Methods: We introduced ectopic expression of inducible B-Raf into human fibroblast cells. We characterized the successfully infected cells based on their ability to induce senescence. Results: We isolated cells of clonal origin and we identified the clone most responsive to B-Raf expression. Conclusions and Future Research: Our methodology proved to be effective in creating a model of B-Raf expression that can be used to study OIS. The next step is to screen the cells to identify genes that enable the cells to evade senescence. These genes could prove to be valuable chemotherapeutic targets.
{"title":"Development of a Cellular System to Identify Modulators of B-Raf Induced Senescence in Human Fibroblasts","authors":"Ran Shu","doi":"10.26443/msurj.v9i1.159","DOIUrl":"https://doi.org/10.26443/msurj.v9i1.159","url":null,"abstract":"Background: B-Raf is one of the earliest and most common genetic mutations observed in many different types of cancers. A single mutation in B-Raf cannot cause full-blown cancer, but may cause an observed phenotype called oncogene induced senescence (OIS). This suggests the need for cooperation between B-Raf and other genes for successful tumorigenesis. \u0000Objective: We look to characterize Human Fibroblast cells that are able to senesce in response to elevated oncogenic expression of B-Raf. \u0000Methods: We introduced ectopic expression of inducible B-Raf into human fibroblast cells. We characterized the successfully infected cells based on their ability to induce senescence. \u0000Results: We isolated cells of clonal origin and we identified the clone most responsive to B-Raf expression. \u0000Conclusions and Future Research: Our methodology proved to be effective in creating a model of B-Raf expression that can be used to study OIS. The next step is to screen the cells to identify genes that enable the cells to evade senescence. These genes could prove to be valuable chemotherapeutic targets.","PeriodicalId":91927,"journal":{"name":"McGill Science undergraduate research journal : MSURJ","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69325500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：