Publications by authors named "MARSHALL W"

Background: Colonoscopy is widely regarded to be the gold standard for colorectal cancer (CRC) detection. Recent studies, however, suggest that the effectiveness of colonoscopy is mostly confined to tumors on the left side of the colon (descending, sigmoid, rectum), and that the technology has poor tumor detection for right-sided (cecum, ascending, transverse) lesions. A minimally invasive test that can detect both left-sided and right-sided lesions could increase the effectiveness of screening colonoscopy by revealing the potential presence of neoplasms in the right-sided "blind spot".

View Article and Find Full Text PDF

A new study by Terasaki et al. highlights the role of physical forces in biological form by showing that connections between stacked endoplasmic reticulum cisternae have a shape well known in classical differential geometry, the helicoid, and that this shape is a predictable consequence of membrane physics.

View Article and Find Full Text PDF

Purpose: To investigate use patterns and learning outcomes associated with the use of Therapy Outcomes By You (TOBY. Playpad, an early intervention iPad application.

Methods: Participants were 33 families with a child with an autism spectrum disorder (ASD) aged 16 years or less, and with a diagnosis of autism or pervasive developmental disorder - not otherwise specified, and no secondary diagnoses.

View Article and Find Full Text PDF

The assembly and maintenance of all cilia and flagella require intraflagellar transport (IFT) along the axoneme. IFT has been implicated in sensory and motile ciliary functions, but the mechanisms of this relationship remain unclear. Here, we used Chlamydomonas flagellar surface motility (FSM) as a model to test whether IFT provides force for gliding of cells across solid surfaces.

View Article and Find Full Text PDF

Cilia are microtubule/membrane-based protrusions that mediate cell motility or transduce sensory information. New work in Chlamydomonas demonstrates that cilia can also act as secretory organelles by budding enzyme-containing vesicles from the flagellar membrane for post-mitotic hatching of daughters from the mother cell wall.

View Article and Find Full Text PDF

Introduction: Chest x-rays (CXR) are routinely obtained on blunt trauma patients. Many patients also receive additional imaging with thoracic computed tomography scans for other indications. We hypothesized that in hemodynamically normal, awake and alert blunt trauma patients, CXR can be deferred in those who will also receive a TCT with significant cost savings.

View Article and Find Full Text PDF

Cilia and flagella are important organelles used for sensing the external cellular environment or for motility. Abnormalities in ciliary structure or function can have devastating pathological consequences ranging from sinusitis and obesity to polycystic kidney disease, retinal degeneration, and mental retardation. Chlamydomonas flagella are excellent models to study the regulation and normal function of cilia.

View Article and Find Full Text PDF

Primary cilia are microtubule-based organelles found on most types of cells in the human body. Although primary cilia were long thought to be vestigial remnants of motile cilia, it is now known that primary cilia play important roles in development and physiology, and defects of primary cilia cause a wide range of human disease symptoms, termed ciliopathies. To understand ciliary functions and the molecular mechanisms underlying ciliopathies, it is important to know the components of primary cilia, but primary cilia have proven to be more difficult to isolate than motile cilia.

View Article and Find Full Text PDF

Planarians are free-living invertebrates that employ motile cilia for locomotion. Specifically, cilia that populate the ventral epithelium of the planarian body are highly conserved, with a 9+2 axoneme and a full complement of inner and outer arm dynein motors. The abundance of cilia on the planarian body, their unique accessibility, and high degree of conservation make this organism an attractive experimental model system for cilia biology.

View Article and Find Full Text PDF

Cilia and flagella are microtubule-based organelles that protrude from the cell body. Ciliary assembly requires intraflagellar transport (IFT), a motile system that delivers cargo from the cell body to the flagellar tip for assembly. The process controlling injections of IFT proteins into the flagellar compartment is, therefore, crucial to ciliogenesis.

View Article and Find Full Text PDF

Background: The authors of prior small studies raised the hypothesis that symptoms in veterans of the 1991 Gulf War, such as chronic diarrhea, dizziness, fatigue, and sexual dysfunction, are due to cholinergic autonomic dysfunction.

Objective: To perform a confirmatory test of this prestated hypothesis in a larger, representative sample of Gulf War veterans.

Design: Nested case-control study.

View Article and Find Full Text PDF

Of the ancient clades of unicellular relatives of the multicellular animals, ichthyosporea are among the easiest to collect, cultivate, and analyze at the population level. Once identified, species can be correlated with their animal hosts and geographical ranges. However, the spherical stages common to many ichthyosporea provide little basis for morphological species identification.

View Article and Find Full Text PDF

The centrosome, a major organizer of microtubules, has important functions in regulating cell shape, polarity, cilia formation and intracellular transport as well as the position of cellular structures, including the mitotic spindle. By means of these activities, centrosomes have important roles during animal development by regulating polarized cell behaviors, such as cell migration or neurite outgrowth, as well as mitotic spindle orientation. In recent years, the pace of discovery regarding the structure and composition of centrosomes has continuously accelerated.

View Article and Find Full Text PDF

The phenomenon of sexual sadism was first scientifically described by Richard von Krafft-Ebing in 1999 as a sexual preference disorder that focuses on the infliction of suffering, pain, or humiliation to achieve sexual gratification. The present article reviews the historical development of the term sexual sadism, including the current descriptive nosology of psychiatric classification. Despite clear definitions that specify the sexual objects, duration, and distress necessary for a disorder, evidence for the diagnostic reliability for sexual sadism in the forensic domain is mixed.

View Article and Find Full Text PDF

Systems level approaches to analyzing complex emergent behavior require quantitative characterization of alterations of behavior on both the microscale and macroscale. Here we consider the problem of cellular organization and describe a statistical methodology for quantitative comparison of the internal organization between different populations of similar physical objects, such as cells. This comparison is achieved with several steps of analysis.

View Article and Find Full Text PDF