Photoacoustic detection of circulating melanoma cells in the plasma layer of the blood [abstract]

Abstract only availableWhen a melanoma patient is diagnosed, aggressive treatment is advised in an effort to contain the disease. Although the initial malignant cells are destroyed, it is impossible to determine whether or not the cancer has metastasized until a secondary tumor forms. This can take months to discover, by which time the cancer could be advanced. Our research focuses on using photoacoustic signals to detect melanoma cells circulating in the blood, allowing for much earlier discovery and treatment of this type of cancer. Photoacoustic signals are produced when a laser illuminates a medium - blood, in this case - and the resultant pressure created by the light causes the medium to emit a sound wave. These waves are specific to the medium being illuminated, and melanoma cells can therefore be differentiated from surrounding blood cells based on the waveform it produces. Our current technique involves the in vitro separation of blood through centrifugation to isolate and test only the white blood cell layer since the contrast between these cells and melanoma cells is clear. Using this method, we have detected a single cancerous cell in the blood stream. However, the process could be made simpler if the plasma layer were used for detection instead of the white blood cell layer. This layer is easier to obtain after blood has been centrifuged, the optical difference between plasma cells and melanoma cells is more pronounced in this layer than in the white blood cell layer, and the possibility that any stray red blood cells could distort the results is eliminated. The primary focus has therefore been to determine whether or not melanoma cells are commonly found in the plasma layer of the blood. If such is the case, this research will be one step closer to revolutionizing the treatment of melanoma patients around the world.College of Engineering Undergraduate Research Optio

Host-parasite associations of the Cratogeomys fumosus species group and their chewing lice, Geomydoecus

Chewing lice (Phthiraptera: Trichodectidae) and the pocket gophers (Rodentia: Geomyidae) that they inhabit have shared an intimate historical association that has made them a textbook study for cophylogeny. Herein, we examine the chewing lice found on pocket gophers of the Cratogeomys fumosus species group using DNA sequence data from the mitochondrial cytochrome c oxidase subunit I gene to determine relationships among lice for comparison to published host phylogeny. Although matrix approaches indicate a correlation between host and parasite genetic distances, cophylogenetic reconstruction methods fail to detect a pattern of widespread cophylogeny. In conclusion, this study provides an exception to the rule of host-parasite cophylogeny that could be the result of the young age of the relationships considered herein and the complex history of the Trans-Mexican Volcanic Belt. Los piojos masticadores (Phthiraptera: Trichodectidae) y las tuzas (Rodentia: Geomyidae) que habitan, han compartido una asociación histórica íntima que los ha convertido en un estudio de libro de texto para la cofilogenia. En el presente estudio, examinamos los piojos masticadores que se encuentran en las tuzas del grupo de especies de Cratogeomys fumosus utilizando los datos de secuencias de ADN del gen mitocondrial Citocromo C Oxidasa subunidad I para determinar las relaciones entre los piojos en comparación con la filogenia publicada del hospedero. Si bien los enfoques matriciales indican una correlación entre las distancias genéticas del hospedero y el parásito, los métodos de reconstrucción cofilogenéticos no detectan un patrón de cofilogenia generalizada. En conclusión, este estudio, proporciona una excepción a la regla de cofilogenia parásito-hospedero que podría ser el resultado de la corta edad de las relaciones consideradas en este documento y la compleja historia del Cinturón Volcánico Trans-Mexicano

Disparate Rates of Molecular Evolution in Cospeciating Hosts and Parasites

DNA sequences for the gene encoding mitochondrial cytochrome oxidase I in a group of rodents (pocket gophers) and their ectoparasites (chewing lice) provide evidence for cospeciation and reveal different rates of molecular evolution in the hosts and their parasites. The overall rate of nucleotide substitution (both silent and replacement changes) is approximately three times higher in lice, and the rate of synonymous substitution (based on analysis of fourfold degenerate sites) is approximately an order of magnitude greater in lice. The difference in synonymous substitution rate between lice and gophers correlates with a difference of similar magnitude in generation times

Temporal and spatial dynamics of competitive parapatry in chewing lice

We synthesize observations from 1979 to 2016 of a contact zone involving two subspecies of pocket gophers (Thomomys bottae connectens and T. b. opulentus) and their respective chewing lice (Geomydoecus aurei and G. centralis) along the Rio Grande Valley in New Mexico, U.S.A., to test predictions about the dynamics of the zone. Historically, the natural flood cycle of the Rio Grande prevented contact between the two subspecies of pocket gophers. Flood control measures completed in the 1930s permitted contact, thus establishing the hybrid zone between the pocket gophers and the contact zone between their lice (without hybridization). Since that time, the pocket gopher hybrid zone has stabilized, whereas the northern chewing louse species has replaced the southern louse species at a consistent rate of similar to 150 m/year. The 0.2-0.8 width of the replacement zone has remained constant, reflecting the constant rate of chewing louse species turnover on a single gopher and within a local pocket gopher population. In contrast, the full width of the replacement zone (northernmost G. centralis to southernmost G. aurei) has increased annually. By employing a variety of metrics of the species replacement zone, we are better able to understand the dynamics of interactions between and among the chewing lice and their pocket gopher hosts. This research provides an opportunity to observe active species replacement and resulting distributional shifts in a parasitic organism in its natural setting

The Impact of Demographic Factors and News Exposure of Child Sexual Abuse in the Mass Media Toward Communication Quality of Parents in Providing Sex Education for Children

Many cases of child sexual abuse become media spotlight, such as print media, TV, and online. However, not all the audience watch the news. They are motivated by differences in demographic factors, such as gender, age, education level, and income level. The cases spread in the mass media should be concern of many parents to pay more attention to the patterns of communication as a way of parents to control the safety of their children. Sex education is considered to be an appropriate way to provide sexual knownledge to children who are vulnerable from the damage of sexual crimes. However, not all parents are willing to deliver sex education to their children.This study employed the theory of social categories explain the difference between social categories can affect the audience\u27s response when receiving message from mass media (Rakhmat, 2011) and media functionalist theory that explain how media exposure can affect their communication activities that occur between the audience (Mc Quail, 1972). The population of this study were the parents of SD Negeri Padangsari 02 Semarang, who have child 10-12 years old. Sampling was done by simple random technique with a number of 63 respondents.The first hypothesis test indicate that the demographic factors of the three variables, those are gender, age, and educational level when calculated simultaneously using regression analysis techniques, do not affect the news exposure of child sexual abuse in the mass media. While the variable of income level has an impact to the news exposure of child sexual abuse in mass media with significance value of 0,011. The second hypothesis test prove that the news exposure of child sexual abuse in the mass media affects the communication quality of parents in providing sex education with a significance value of 0,001.Advice can be given from this study is that parents should pay more attention to their way to communicate with children, especially regarding sex education. Sex education can be good when it is given according to the child\u27s age and their understanding level considering the number of cases of sexual abuse is increase as in the media

The Mitochondrial Cytochrome Oxidase Subunit I Gene Occurs on a Minichromosome with Extensive Heteroplasmy in Two Species of Chewing Lice, Geomydoecus aurei and Thomomydoecus minor

In animals, mitochondrial DNA (mtDNA) typically occurs as a single circular chromosome with 13 protein-coding genes and 22 tRNA genes. The various species of lice examined previously, however, have shown mitochondrial genome rearrangements with a range of chromosome sizes and numbers. Our research demonstrates that the mitochondrial genomes of two species of chewing lice found on pocket gophers, Geomydoecus aurei and Thomomydoecus minor, are fragmented with the 1,536 base-pair (bp) cytochrome-oxidase subunit I (cox1) gene occurring as the only protein-coding gene on a 1,916–1,964 bp minicircular chromosome in the two species, respectively. The cox1 gene of T. minor begins with an atypical start codon, while that of G. aurei does not. Components of the non-protein coding sequence of G. aurei and T. minor include a tRNA (isoleucine) gene, inverted repeat sequences consistent with origins of replication, and an additional non-coding region that is smaller than the non-coding sequence of other lice with such fragmented mitochondrial genomes. Sequences of cox1 minichromosome clones for each species reveal extensive length and sequence heteroplasmy in both coding and noncoding regions. The highly variable non-gene regions of G. aurei and T. minor have little sequence similarity with one another except for a 19-bp region of phylogenetically conserved sequence with unknown function

Characterization of a New mtDNA Minicircle in a Chewing Louse, Geomydoecus aurei

The mitochondrion, an organelle responsible for generating cellular energy, is unlike the majority of organelles in animal cells. Because of its symbiotic origins, the mitochondrion contains its own genetic information (mtDNA) that is predominantly maternally inherited. In most animals, the mitochondrial DNA is arranged in one circular chromosome containing 13 protein coding genes, 22 tRNAs and two rRNAs. In Geomydoecus aurei, a chewing louse, these same genes have been disbursed among at least 13 independent minicircle chromosomes. We have worked to map this atypical genome to gain insights into its development and to further understanding of genomic rearrangements in this important genetic material. Identification and characterization of the unique nature of this mtDNA may lead to a better understanding of many debilitating disorders associated with mitochondrial dysfunction

Mitochondrial genome of Geomydoecus aurei, a pocket-gopher louse

Parasitic lice demonstrate an unusual array of mitochondrial genome architectures and gene arrangements. We characterized the mitochondrial genome of Geomydoecus aurei, a chewing louse (Phthiraptera: Trichodectidae) found on pocket gophers (Rodentia: Geomyidae) using reads from both Illumina and Oxford Nanopore sequencing coupled with PCR, cloning, and Sanger sequencing to verify structure and arrangement for each chromosome. The genome consisted of 12 circular mitochondrial chromosomes ranging in size from 1,318 to 2,088 nucleotides (nt). Total genome size was 19,015 nt. All 37 genes typical of metazoans (2 rRNA genes, 22 tRNA genes, and 13 protein-coding genes) were present. An average of 26% of each chromosome was composed of non-gene sequences. Within the nongene region of each chromosome, there was a 79-nt nucleotide sequence that was identical among chromosomes and a conserved sequence with secondary structure that was always followed by a poly-T region. We hypothesize that these regions may be important in the initiation of transcription and DNA replication, respectively. The G. aurei genome shares 8 derived gene clusters with other chewing lice of mammals, but in G. aurei, genes on several chromosomes are not contiguous

Trends in Cirrhosis and Mortality by Age, Sex, Race, and Antiviral Treatment Status Among US Chronic Hepatitis B Patients (2006-2016)

BACKGROUND: Changing US demographics and evolving chronic hepatitis B (CHB) treatments may affect longitudinal trends in CHB-related complications. We studied trends in the prevalence of cirrhosis (past or present) and incidence of all-cause mortality, stratified by patient age, sex, race, and antiviral treatment status, in a sample from US health care systems. METHODS: Joinpoint and Poisson regression (univariate and multivariable) were used to estimate the annual percent change in each outcome from 2006 to 2016. RESULTS: Among 5528 CHB patients, cirrhosis prevalence (including decompensated cirrhosis) rose from 6.7% in 2006 to 13.7% in 2016; overall mortality was unchanged. Overall rates of cirrhosis and mortality were higher among treated patients, but adjusted annual percent changes (aAPC) were significantly lower among treated than untreated patients (cirrhosis: aAPC +2.4% vs. +6.2%, mortality: aAPC -3.9% vs. +4.0%). Likewise, among treated patients, the aAPC for mortality declined -3.9% per year whereas among untreated patients, mortality increased +4.0% per year. CONCLUSIONS: From 2006 to 2016, the prevalence of cirrhosis among CHB patients doubled. Notably, all-cause mortality increased among untreated patients but decreased among treated patients. These results suggest that antiviral treatment attenuates the progression of cirrhosis and the risk of death among patients with CHB