Nasal Adenocarcinoma in the Canine

Neoplasms of the nasal and paranasal sinuses make up approximately 1% of canine tumors. These tumors are malignant in 80 % of the cases, and 60 - 75 % are carcinomas. According to most authors, adenocarcinomas are the most common nasal tumor, followed by squamous cell carcinoma. Large and medium sized dogs in the 8-10 year age group are most commonly affected. Some authors find the dolicocephalic breeds to be the most prone to develop adenocarcinoma, while others find the number of cases higher in the mesocephalic breeds. Some reports show a higher incidence of nasal adenocarcinoma in male dogs, but when correction is made for sex distribution of the number of cases seen, there is no difference in nasal tumor incidence between males and females. There is no known etiological agent for nasal adenocarcinoma, and there is no difference between urban and rural dogs with respect to nasal and sinus neoplasia

Model-Driven Designs of an Oscillating Gene Network

ABSTRACT The current rapid expansion of biological knowledge offers a great opportunity to rationally engineer biological systems that respond to signals such as light and chemical inducers by producing specific proteins. Turning on and off the production of proteins on demand holds great promise for creating significant biotechnological and biomedical applications. With successful stories already registered, the challenge still lies with rationally engineering gene regulatory networks which, like electronic circuits, sense inputs and generate desired outputs. From the literature, we have found kinetic and thermodynamic information describing the molecular components and interactions of the transcriptionally repressing lac, tet, and ara operons. Connecting these components in a model gene network, we determine how to change the kinetic parameters to make this normally nonperiodic system one which has well-defined oscillations. Simulating the designed lac-tet-ara gene network using a hybrid stochastic-discrete and stochastic-continuous algorithm, we seek to elucidate the relationship between the strength and type of specific connections in the gene network and the oscillatory nature of the protein product. Modeling the molecular components of the gene network allows the simulation to capture the dynamics of the real biological system. Analyzing the effect of modifications at this level provides the ability to predict how changes to experimental systems will alter the network behavior, while saving the time and expense of trial and error experimental modifications

Divergent evolution of protein conformational dynamics in dihydrofolate reductase.

Molecular evolution is driven by mutations, which may affect the fitness of an organism and are then subject to natural selection or genetic drift. Analysis of primary protein sequences and tertiary structures has yielded valuable insights into the evolution of protein function, but little is known about the evolution of functional mechanisms, protein dynamics and conformational plasticity essential for activity. We characterized the atomic-level motions across divergent members of the dihydrofolate reductase (DHFR) family. Despite structural similarity, Escherichia coli and human DHFRs use different dynamic mechanisms to perform the same function, and human DHFR cannot complement DHFR-deficient E. coli cells. Identification of the primary-sequence determinants of flexibility in DHFRs from several species allowed us to propose a likely scenario for the evolution of functionally important DHFR dynamics following a pattern of divergent evolution that is tuned by cellular environment

From Disciplinarian to Change Agent: How the Civil Rights Era Changed the Roles of Student Affairs Professionals

Little has been written about the roles and functions of student affairs administrators during the civil rights era. Therefore, the purpose of this study was to examine how the civil rights era influenced the student affairs profession, paying particular attention to the roles played by student affairs administrators in relation to students, other administrators, and the community. A secondary analysis was conducted based on interviews with 18 student affairs professionals who served on a variety of college campuses during the civil rights era, primarily from the 1950s through the 1970s. Our findings suggest that these administrators took on roles such as educator, advocate, mediator, initiator, and change agent in order to effectively and efficiently resolve issues that arose on their campuses as a result of the civil rights era and the student protest movement. Colleges and universities have been the battleground for many important civil rights concerns, and many authors have chronicled student social movements of this era (Adelman, 1972; Altbach, 1973; Strauss & Howe, 1997). In both northern and southern colleges and universities, integration of African Americans into higher education was a slow and difficult process (Clark, 1993; Cohodas, 1997; Exum, 1985). Once on campus, African American students had to deal with segregation in all types of out-of-class domains including housing, cafeterias, social activities, organized student groups (including athletics, fraternities, and sororities), availability of scholarships, on-campus and off-campus jobs, and access to barber shops and beauty parlors. Student affairs administrators were in the middle of this battlefield and played a key role in representing student demands to the administration and sometimes advocating for change to occur (Clark, 1993; Laliberte, 2003; Tuttle, 1996). Simultaneously, the presidents of many college and university campuses expected the student affairs staff to represent the institutions’ views to the students and to mete out discipline to students who failed to follow the campus rules. These conflicting demands—the desire to support students and the desire to be seen as effective administrators—put many student affairs administrators in precarious positions (Nichols, 1990). Nevertheless, student affairs professionals in the civil rights era served as communication links between the administration and students and experienced enhanced status and advancement to higher administrative positions. In the process, their experiences exerted considerable influence on the student affairs profession itself. By examining the stories of student affairs administrators, we learn firsthand how the civil rights era affected the profession. This article provides a glimpse into civil rights struggles on campus as seen through their eyes. Unfortunately, little has been written about the roles and functions of student affairs administrators during the civil rights era. One study by Crookston and Atkyns (1974) found that during the period of unrest in the 1960s, many senior student affairs officers left their positions. They also concluded that during this period student affairs administrators became known as crisis managers, and most colleges and universities elevated the chief student affairs officer from dean to vice president. In recent research that examined student affairs during the turbulent years of 1968-1972, Laliberte (2003) 1 confirmed the crisis manager and student advocate roles of student affairs administrators. For the purpose of this article, a secondary analysis of the data collected for the book Reflecting Back, Looking Forward: Civil Rights and Student Affairs (Wolf-Wendel et al., 2004) was conducted to examine how the civil rights era influenced the student affairs profession, paying particular attention to the roles played by student affairs administrators in relation to students, other administrators, and the community. The book told the stories of individuals in first person narrative form; however, this article focuses specifically on how participation during the civil rights era affected the profession itself

Gcn4-Mediator Specificity Is Mediated by a Large and Dynamic Fuzzy Protein-Protein Complex.

Transcription activation domains (ADs) are inherently disordered proteins that often target multiple coactivator complexes, but the specificity of these interactions is not understood. Efficient transcription activation by yeast Gcn4 requires its tandem ADs and four activator-binding domains (ABDs) on its target, the Mediator subunit Med15. Multiple ABDs are a common feature of coactivator complexes. We find that the large Gcn4-Med15 complex is heterogeneous and contains nearly all possible AD-ABD interactions. Gcn4-Med15 forms via a dynamic fuzzy protein-protein interface, where ADs bind the ABDs in multiple orientations via hydrophobic regions that gain helicity. This combinatorial mechanism allows individual low-affinity and specificity interactions to generate a biologically functional, specific, and higher affinity complex despite lacking a defined protein-protein interface. This binding strategy is likely representative of many activators that target multiple coactivators, as it allows great flexibility in combinations of activators that can cooperate to regulate genes with variable coactivator requirements

Validity of Adolescents' Report of Maternal Age

Examined the validity of adolescents' reports of their mother's age. Most research on the validity of self-report focuses on personal behaviors such as alcohol and substance use, or response bias due to social desirability. Few studies investigate the validity of adolescents reporting of nonsensitive information. Data from 80 mother–adolescent pairs were collected. The sample included 9th graders from four high school English classes, equal numbers of males and females, and 15% African Americans. The correlation between mothers' reports and youths' reports of mother's age was .99, and 95% of the youth were within a year of their mother's correct age. No race or gender differences were found. These results allow researchers to examine adolescent outcomes for youth born to teen mothers without the expense of also collecting data from their mothers. Results also suggest that adolescents' self-reports of other nonsensitive familial data may also be valid.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44048/1/10464_2004_Article_417398.pd

Psychosocial Outcomes of Urban African American Adolescents Born to Teenage Mothers

This is a study of psychosocial outcomes of adolescents born to teenage mothers. Adolescents' problem behaviors, psychological well-being, social support, school variables, and sexual behaviors are compared across three groups—those born to mothers 17 or younger, mothers 18–19 years old, and mothers 20 or older. Analyses from two samples of African American adolescents from Maryland ( n = 205) and Michigan ( n = 570) are reported. The results from both samples indicate that mother's age at birth is unrelated to adolescents' psychosocial outcomes. These two studies add to the limited number of analyses that examine adolescent outcomes for children of teen mothers. The results suggest that efforts to understand social structural determinants of healthy and problematic adolescent development may be more informative than examining the effects of mother's age. They also suggest that teen pregnancy prevention programs may be more effective if they are part of a larger prevention strategy that incorporates social structural change efforts and not only a focus on individual level change.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44057/1/10464_2004_Article_343152.pd

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe