Spring 2021最新文献

{"title":"Cancer Models to Defeat Therapy Resistance in Pancreatic Ductal Adenocarcinoma","authors":"Britney He","doi":"10.48091/gsr.v1i2.21","DOIUrl":"https://doi.org/10.48091/gsr.v1i2.21","url":null,"abstract":"One of the largest hurdles to the efficacy of cancer therapeutics, and a main cause of relapse, is therapy resistance. In response, researchers have developed model systems to better understand therapy resistance. Cancer research employs several model systems that reflect the biology of actual human tumors: in vitro models (2D, 3D cell cultures), in vivo models (PDX, GEMMS, transgenic), proteomic models, and computational or mathematical models. One cancer that has been extensively modeled is pancreatic ductal adenocarcinoma (PDAC). PDAC is the third most common cause of annual cancer deaths in developed countries; as its incidence and mortality rates continue to increase, PDAC is projected to be the second leading cause of cancer deaths by 2030. Although chemotherapy is a pillar of clinical PDAC treatment, its outcome typically leads to multi-drug resistance, drastically restricting the curative effect of drugs for a variety of tumors. Elucidating the underlying mechanisms for resistance through different models is essential for the development of new strategies and therapies. This review provides insight into the range of in vitro and in vivo models of pancreatic cancer used in preclinical research. This paper provides an overview of platforms for cancer research with a focus on those devoted to resistance mechanisms in PDAC and to the primary therapeutic intervention for PDAC, gemcitabine (GEM).","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"2012 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127379694","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}

{"title":"The Burn Behind the Bullet: Understanding Black Mothers’ Experiences After Losing a Child to Gun Violence in Washington, DC-Baltimore City Metropolitan Region","authors":"D. Brown","doi":"10.48091/gsr.v1i2.20","DOIUrl":"https://doi.org/10.48091/gsr.v1i2.20","url":null,"abstract":"The purpose of this research article is to examine how complicated grief, post-traumatic stress, and depressive symptoms induced from losing a child to gun violence affect traits of resilience and post-traumatic growth among a sample of Black mothers living in Washington DC and Baltimore, Maryland. This research project was executed by surveying 4 Black mothers who lost a child to gun violence (B.M.C.G.V.) that resided in the Baltimore-Washington area to assess grief, traumatic stress, and depression. Participants also completed an oral interview that focused on resilience, post-traumatic growth, and policy recommendations. Findings associated with post-traumatic stress indicated that all Black mothers in this study reported it was somewhat true that they avoid things that remind them of their loved ones (n= 4, 100%), and 3 out of 4 of the mothers felt cut off or distant from other people since their loved one died (n= 3, 75%). Outcomes related to complicated grief revealed that all mothers in this study reported that they felt a great deal of loneliness since their child had died (n= 4, 100%). Moreover, 3 out 4 B.M.C.G.V. reported that memories of their child made them upset in the last past 7 days (n= 3, 75%). Results aligning with post-traumatic growth displayed that all Black mothers in this study reported it was mostly true that they learned they were stronger than they originally thought they were after losing a child to gun violence (n=4, 100%). Additionally, 3 out of 4 Black mothers in this study stated that it is mostly true that they developed a strong religious faith upon losing a child to gun violence (n= 3, 75%). Furthermore, 3 out of 4 Black mothers in this study reported that they found a stronger sense of purpose in life upon losing a child to gun violence (n = 3, 75%). Findings related to depressive symptomatology contained a large amount of variation and did not produce any significant results. The data results from the oral interview indicated that 9 common characteristics emerged from Black mothers who lost a child to gun violence in this study which included Black mothers explaining their character traits as Loving, Committed, and Strong. Subsequently, Black mothers classified their coping strategies as Active Coping (Embracing Self-love, Forgiveness, and Faith in God) and Avoidant Coping (Denial, Betrayal, and Not Coping). Lastly, Black mothers’ policy recommendations in this study focused on themes such as Demanding resources and Laws on gun violence prevention.","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114389116","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}

{"title":"GPR40 and Postsynaptic NMDA Receptors: A Pair Against Epilepsy","authors":"Vidya Mullangi, N. Shah, Hyunwook Nam, Alexa Asch, Lauren Cox, Clarisa Mendoza","doi":"10.48091/gsr.v1i2.19","DOIUrl":"https://doi.org/10.48091/gsr.v1i2.19","url":null,"abstract":"Epilepsy is a chronic neurological condition characterized by abnormal brain activity, unusual behavior, and loss of awareness. One of the most common features is the spontaneous recurrence of unprovoked seizures that mainly affect the hippocampus and cortical regions of the brain. Although the exact cause of epilepsy is still unknown, a mix of genetic, neurological, and environmental factors play a role. A novel study by Yang et al. explores the metabotropic receptor GPR40 which is suspected to be involved in the regulation of epileptic seizures, specifically through its modulatory role on NMDA receptors in the central nervous system. Their findings suggest that GPR40 induces NMDA receptor endocytosis via direct interaction with NR2A and NR2B subunits of postsynaptic NMDA receptors. Through this mechanism, NMDA-mediated postsynaptic currents are altered, resulting in reduced seizure-like activity. This review article discusses these novel findings which not only shed light on the potential molecular mechanisms of epilepsy but also push the scientific community closer to developing a treatment for this disorder.","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"256 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114323762","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}

{"title":"Letter from the Editors","authors":"Nesreen Shahrour, Danya A. Adams","doi":"10.48091/gsr.v1i2.22","DOIUrl":"https://doi.org/10.48091/gsr.v1i2.22","url":null,"abstract":"This spring semester marks an unprecedented year for the Georgetown community and beyond. The ability of many student researchers to adapt their research studies to a virtual environment, something previously unimaginable, is nothing short of a remarkable display of the resilience and adaptability of the Georgetown student body. Students turned to writing literature reviews and conducting data analyses to delve deeper into their research virtually. This pattern was reflected in the numerous literature reviews present in this issue as well as in Student Highlights throughout the school year. These unanticipated changes students made to the way they conduct research are inspiring to the research community as a whole and show their passion and desire to further scientific research despite the many new challenges we face.In this issue, we are met with a diversity of research conducted by these committed students. They have tackled a variety of important topics ranging from gun violence to cancer models. This issue presents many fascinating and thought-provoking studies: a new, original program for decryption techniques on python, a review about the target receptor GPR40 for epilepsy treatment, original research regarding the psychological healing of Black women in the DC area following losing a child to gun violence, and a review of cancer models in pancreatic ductal adenocarcinoma therapy. We hope this issue will serve as a testament to true commitment that will always find a way to move forward despite a pandemic that challenged the safety of conducting research via traditional methods. As we transition into our second year as an organization, we hope to continue contributing to the scientific student experience at Georgetown University. To honor our dedication to the Georgetown research community, the Center for Student Engagement presented GSR Journal with the Outstanding Student Organization Award. Through resources on how to get involved in research and showcasing the work of our community members, we hope students will learn more about the myriad research opportunities at Georgetown. Please join us in commending the students who have advanced the ongoing research at Georgetown University both in this issue and beyond.","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124222969","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}

{"title":"An Investigation Into the Mathematics of Decryption Techniques in RSA Encryption, With an Implementation in Python","authors":"Sofia Flynn","doi":"10.48091/gsr.v1i2.18","DOIUrl":"https://doi.org/10.48091/gsr.v1i2.18","url":null,"abstract":"This study explores the mathematics of two different techniques that can be used to access the decryption key in RSA encryption including semi-prime factorization and a logarithmic method. The study then presents a Python program, written by the author, that automates the calculations for either of the decryption techniques and also calculates the number of iterations required to determine the decryption key in either circumstance. Most importantly, the program utilizes only values of the RSA encryption algorithm that would be made publicly available in actual circumstances to calculate the decryption key so as to mimic real-life occurrences with as much integrity and accuracy as possible.","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116796969","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}

{"title":"A case of facultative aggregation in the oriental garden lizard\u0000Calotes cf. versicolor Daudin, 1802 (Squamata: Agamidae)","authors":"A. Shinde, Avrajjal Ghosh","doi":"10.33256/HB155.3637","DOIUrl":"https://doi.org/10.33256/HB155.3637","url":null,"abstract":"","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125720490","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}

{"title":"Sleeping site fidelity in three neotropical species of herpetofauna","authors":"Oliver Thomas, G. Mangini, Juan Gualinga","doi":"10.33256/HB155.811","DOIUrl":"https://doi.org/10.33256/HB155.811","url":null,"abstract":"A animal species studied to date have shown sleep or sleep-like behaviour (Tobler, 2000). Sleep aids in a variety of processes including recovery of cellular and endocrine systems through to learning, memory and energy conservation (Mignot, 2008; Libourel & Herrel, 2016). At the same time, periods of sleep could present risks as an animal may be exposed to predation while inactive (Amlaner & Ball, 1983). Regardless of its functions, sleep is among the most prominent of animal behaviours and as such is likely to be a behaviour that responds dynamically and adaptively to different environmental variables (Tobler, 2000). Sleeping site selection must play an important role in obtaining the benefits of sleep while avoiding predation (Amlaner & Ball, 1983). It is likely influenced by microhabitat preferences, the need for protection from predators or exposure, and remaining within territories to avoid competition (Christian et al., 1984; Clark & Gillingham, 1990). Thus, once selected, a sleeping site may be maintained through days, weeks, or longer, to retain these benefits over time (González-Zamora et al., 2015). However, to date studies of sleeping site preferences or site fidelity have focused mainly on endotherms (mammals and birds) rather than ectotherms such as reptiles, amphibians, fishes or invertebrates (Amlaner & Ball, 1983; Campbell & Tobler, 1984; Christian et al., 1984; Clark & Gillingham, 1990; Hartse, 1994). In reptiles specifically, sleeping sites have been recorded widely in anoles, including some Amazonian species such as Anolis punctatus, Anolis trachyderma and Anolis transversalis. However, there is far less information for other reptiles and amphibians (Clark & Gillingham, 1990; Vitt et al., 2002; Vitt et al., 2003a; Vitt et al., 2003b; Poche et al., 2005). Here we report sleep site fidelity for two species of lizard Enyalioides laticeps (Guichenot, 1855) and Anolis fuscoauratus D’Orbigny, 1937 and one amphibian species, the toad Rhinella margaritifera (Laurenti, 1768). To gather data, we undertook day and night-time visual encounter surveys between June and August 2019 in the camping area of the Sani Reserve, Sucumbíos, Ecuador (0° 26’ 18.47” S, 76° 16’ 45.11” W). The habitat in the Sani Reserve is a mixture of mostly terra firme forest, igapó (blackwater flooded forest) and varzea (white water flooded forest) with the Challuacocha lagoon and its surrounding reeds and grasses located around the reserve’s ecolodge (Hollamby, 2010). Six trails were surveyed on separate days on a rotational basis. During these surveys we first recorded E. laticeps and R. margaritifera sleeping on 10th July, and recorded them again on 17th July. Sleeping was determined through behavioural indicators such as closed eyes upon our arrival, lack of escape behaviour, or time of observation outside the reported diel activity pattern. In the camp, we recorded an individual A. fuscoauratus that was returning to sleep in the same site from the 19th July. We p","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114826845","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}

{"title":"A tree frog Scinax perereca predated by a wandering spider\u0000Phoneutria keyserlingi in Brazil","authors":"E. Saito, Guilherme B Willrich, Ana Letícia Trivia","doi":"10.33256/HB155.3435","DOIUrl":"https://doi.org/10.33256/HB155.3435","url":null,"abstract":"A are an important component of food chains in natural ecosystems (Wells, 2007; Haddad et al., 2008). They are preyed upon by a large variety of taxa both vertebrates and invertebrates such as ants, beetles, crabs and spiders (Duellman & Trueb, 1994; Toledo, 2005; Toledo et al., 2007). Spiders of several families have been recorded as anuran predators (Menin et al., 2005) and we present here the first report of the spider Phoneutria keyserlingi Perty, 1833 (Aranae, Ctenidae) preying upon the tree frog Scinax perereca Pombal, Haddad & Kasahara, 1995 (Anura, Hylidae). Scinax perereca ranges from São Paulo to Rio Grande do Sul states in Brazil, north-eastern Misiones Province in Argentina to southern Paraguay (Frost, 2020; Aquino et al., 2004). It inhabits forests and forest edges between 0 to 1,000 m asl, where it reproduces in temporary or permanent pools and is also commonly observed sheltered in human habitations (Aquino et al., 2004; Pombal et al., 1995). Phoneutria keyserlingi is a wandering spider from the Atlantic Forest distributed on the coastal regions of São Paulo, Rio de Janeiro, Paraná and Santa Catarina states in Brazil (Martins & Bertani, 2007). Our field observations were made on 25th July 2011 at 18:50 h, at Ponta-do-Araçá Environmental Protected Area, municipality of Porto Belo, Santa Catarina state, southern Brazil (27° 07’21.10” S; 48° 30’53.30” W; 70 m asl). We observed a spider (P. keyserlingi) that had grasped a tree frog (S. perereca) dorsally with its chelicerae in a bromeliad on a tree (Fig. 1), a few meters from a small lake surrounded by secondary growth tropical moist forest. The observation lasted a few minutes, but neither the spider nor the tree frog were collected. Leaf litter anurans can be a potential prey to grounddwelling spiders, especially from the families Ctenidae and Pisauridae (Menin et al., 2005). There are at least five published reports of anuran predation by ctenid spiders of the genus Phoneutria relating to Phoneutria nigriventer, for example Folly et al. (2017). Since the current predation event occurred in a bromeliad at approximately 2 m above the ground, it must be the case that tree frogs such as S. perereca are part of the diet of wandering spiders when they are foraging above the forest floor. ACKNOWLEDGEMENTS","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123883277","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}

{"title":"First observation of male combat in the\u0000greater black krait Bungarus niger","authors":"M. Malsawmdawngliana","doi":"10.33256/HB155.3233","DOIUrl":"https://doi.org/10.33256/HB155.3233","url":null,"abstract":"T greater black krait Bungarus niger Wall, 1908 (Serpentes: Elapidae) is a venomous snake distributed from north-east India, Nepal, Bhutan and Bangladesh to Myanmar (Whitaker & Captain, 2004; Leviton et al., 2008; Lalremsanga & Lalronunga, 2017; Uetz, 2020). It is easily identified by its coloration (iridescent black to dark chocolate dorsally and off-white ventrally) and presence of enlarged hexagonal vertebral scales (Whitaker & Captain, 2004). Little information is available on the natural history of B. niger especially its reproductive behaviour and no intraspecific competition had been recorded previously. Male combat has been observed and described in many species of snakes from different families, with varying rituals and behaviours (Shine, 1978; Senter et al., 2014) including the Malayan krait, Bungarus candidus (Shine, 1978). Herein, we report the first record of male combat behaviour in B. niger. On the 2nd October 2017 at 13:53 h, we witnessed two adult male B. niger engaging in male combat (Fig. 1) near Lamchhip village, Aizawl District, Mizoram, north-east India (23 ̊ 26.497’ N, 92 ̊ 47.114’ E; 1,177 m asl). The snakes were caught in the act and the bout was observed for about 10 minutes, until they moved out of sight into a thicket along the road, continuing with the combat. The two snakes intertwined their bodies while moving forward (Fig. 1A D), raised their head almost up to a fifth of their total length (Fig. 1D) and tried to push the head of the opponent to the ground (Fig. 1A B). One male was observed biting the neck of its opponent (Fig. 1C), which is an apparently rare phenomenon in male combat (Senter et al., 2014). During the encounter, no female was sighted nearby although this would be expected as male combat in snakes is normally associated with competition to mate with a The Herpetological Bulletin 155, 2021: 32-33","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122766169","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}

{"title":"Exceptional longevity of a male Madeira rock lizard Teira dugesii\u0000maintained in captivity for 41 years","authors":"Kees Margry, W. Heitmans","doi":"10.33256/HB155.1517","DOIUrl":"https://doi.org/10.33256/HB155.1517","url":null,"abstract":"M reptiles in captivity can give clues about their longevity. As expected, longevities in captivity have increased with the development of better care and husbandry; the first reports on reptiles life spans achieved in zoological gardens (Flower, 1925) are shorter than those reported in more recent studies (Bannert, 1998; Slavens & Slavens, 1999; Mendyk, 2014b). Herein, we recount the remarkably 41 year lifespan of a captive male Teira dugesii (Milne-Edwards, 1829).","PeriodicalId":201345,"journal":{"name":"Spring 2021","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122183734","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}