Frazzled/DCC facilitates cardiac cell outgrowth and attachment during Drosophila dorsal vessel formation.

Drosophila embryonic dorsal vessel (DV) morphogenesis is a highly stereotyped process that involves the migration and morphogenesis of 52 pairs of cardioblasts (CBs) in order to form a linear tube. This process requires spatiotemporally-regulated localization of signaling and adhesive proteins in order to coordinate the formation of a central lumen while maintaining simultaneous adhesion between CBs. Previous studies have shown that the Slit/Roundabout and Netrin/Unc5 repulsive signaling pathways facilitate site-specific loss of adhesion between contralateral CBs in order to form a luminal space.

History of metaphoric signs in radiology.

Purpose: To survey the nearly 100 year history of metaphoric sign naming in radiology describing the pace of their overall accumulation in the radiology canon, their specific rates of growth by modality and subspecialty and the characteristics of the referents to which the signs are attached.

Materials And Methods: A comprehensive list of metaphoric signs was compiled from a search of articles in several major English language radiology journals, from a roster compiled in a monograph on the subject published in 1984 and from a search of several databases to find signs published in the first half of the 20th century.

Results: The growth of radiological metaphorical signs naming was slow for several decades after the first one was published in 1918.

Effect of pit and fissure sealants on caries detection by a fluorescent camera system.

Objective: The aim of this study was to evaluate the effect of sealant placement on the detection of caries by a fluorescent camera (FC), the Spectra caries detector.

Materials And Methods: In a laboratory study, FC images and readings were obtained from 31 extracted teeth, before and following application of clear sealants (Shofu Clear or Delton unfilled), or opaque sealants (3M Clinpro or Delton FS). Teeth were then sectioned and examined for enamel or dentine caries.

Position of the academy of nutrition and dietetics: ethical and legal issues in feeding and hydration.

It is the position of the Academy of Nutrition and Dietetics that individuals have the right to request or refuse nutrition and hydration as medical treatment. Registered dietitians (RDs) should work collaboratively as part of the interprofessional team to make recommendations on providing, withdrawing, or withholding nutrition and hydration in individual cases and serve as active members of institutional ethics committees. RDs have an active role in determining the nutrition and hydration requirements for individuals throughout the life span.

Comparison of sealing ability of MTA and EndoSequence Bioceramic Root Repair Material: a bacterial leakage study.

Objective: To compare the sealing ability of ProRoot mineral trioxide aggregate (MTA) to the sealing ability of EndoSequence Bioceramic Root Repair Material (ES-BCRR) putty using a bacterial leakage model.

Method And Materials: Root canals of 60 single-rooted extracted teeth were enlarged to an apical diameter of 0.5 mm using EndoSequence files.

Metabolic states following accumulation of intracellular aggregates: implications for neurodegenerative diseases.

The formation of intracellular aggregates is a common etiology of several neurodegenerative diseases. Mitochondrial defects and oxidative stress has been pointed as the major mechanistic links between the accumulation of intracellular aggregates and cell death. In this work we propose a "metabolic cell death by overcrowding" as an alternative hypothesis.

Laboratory diagnosis of HIV in adults: a review of current methods.

Of the estimated 1.2 million people infected with human immunodeficiency virus (HIV) in the United States, 20% are unaware of their diagnosis. Improved methods of HIV testing could decrease this number, as well as identify those who have recently acquired HIV infection and are at the most critical stage of infectivity.

Schizophrenia-related phenomena that challenge prediction error as the basis of cognitive functioning.

There are aspects of schizophrenia that pose challenges for Clark's model. These include: (1) evidence for excitatory activity underlying self-organizing neural ensembles that support coordinating functions, and their impairment in schizophrenia; (2) evidence regarding hallucinations that suggest they are not due to excessive prediction error; and (3) the critical role of emotional factors as setting conditions for delusion formation.

TAM receptors in apoptotic cell clearance, autoimmunity, and cancer.

Receptor tyrosine kinases, Tyro-3, Axl and Mer, collectively designated as TAM, are involved in the clearance of apoptotic cells. TAM ligands, Gas6 and Protein S, bind to the surfaces of apoptotic cells, and at the same time, interact directly with TAM expressed on phagocytes, impacting the engulfment and clearance of apoptotic cells and debris. The well-tuned and balanced actions of TAM may affect a variety of human pathologies including autoimmunity, retinal degeneration, and cancer.

Viral DNA tethering domains complement replication-defective mutations in the p12 protein of MuLV Gag.

The p12 protein of murine leukemia virus (MuLV) group-specific antigen (Gag) is associated with the preintegration complex, and mutants of p12 (PM14) show defects in nuclear entry or retention. Here we show that p12 proteins engineered to encode peptide sequences derived from known viral tethering proteins can direct chromatin binding during the early phase of viral replication and rescue a lethal p12-PM14 mutant. Peptides studied included segments of Kaposi sarcoma herpesvirus latency-associated nuclear antigen (LANA)(1-23), human papillomavirus 8 E2, and prototype foamy virus chromatin-binding sequences.

HIV prevalence, risk behavior, knowledge, and beliefs among women seeking care at a sexually transmitted infection clinic in Mumbai, India.

Three hundred women presenting to a sexually transmitted infection (STI) clinic in Mumbai, India were surveyed and HIV tested. Thirty-nine percent were HIV infected; 80% were current sex workers, and HIV infection was not significantly associated with past-year sex work. Only 44% always used condoms with their noncommercial sex partners.

Predatory bacteria: a potential ally against multidrug-resistant Gram-negative pathogens.

Multidrug-resistant (MDR) Gram-negative bacteria have emerged as a serious threat to human and animal health. Bdellovibrio spp. and Micavibrio spp.

Mitochondrial dysfunction, oxidative stress, and major depressive disorder.

There is controversy about depression being a physical illness, in part because a reproducible, sensitive, and specific biologic marker is not available. However, there is evidence that mitochondrial dysfunction and oxidative stress may be associated with abnormal brain function and mood disorders, such as depression. This paper reviews selected human and animal studies providing evidence that intracellular mitochondrial metabolic dysfunction in specific brain regions is associated with major depressive disorder.

Phosphorylation-dependent conformational changes and domain rearrangements in Staphylococcus aureus VraR activation.

Staphylococcus aureus VraR, a vancomycin-resistance-associated response regulator, activates a cell-wall-stress stimulon in response to antibiotics that inhibit cell wall formation. X-ray crystal structures of VraR in both unphosphorylated and beryllofluoride-activated states have been determined, revealing a mechanism of phosphorylation-induced dimerization that features a deep hydrophobic pocket at the center of the receiver domain interface. Unphosphorylated VraR exists in a closed conformation that inhibits dimer formation.

Cardiorespiratory biomarker responses in healthy young adults to drastic air quality changes surrounding the 2008 Beijing Olympics.

Associations between air pollution and cardiorespiratory mortality and morbidity have been well established, but data to support biologic mechanisms underlying these associations are limited. We designed this study to examine several prominently hypothesized mechanisms by assessing Beijing residents' biologic responses, at the biomarker level, to drastic changes in air quality brought about by unprecedented air pollution control measures implemented during the 2008 Beijing Olympics. To test the hypothesis that changes in air pollution levels are associated with changes in biomarker levels reflecting inflammation, hemostasis, oxidative stress, and autonomic tone, we recruited and retained 125 nonsmoking adults (19 to 33 years old) free of cardiorespiratory and other chronic diseases.

Vitamin D biology revealed through the study of knockout and transgenic mouse models.

Early studies identifying vitamin D as an antirachitic factor led to studies in vitamin D-deficient models that resulted in a basic understanding of the mechanism of action of vitamin D. Recent studies using genetically modified mice have provided important new insight into the physiological role of vitamin D at target tissues and the functional significance of vitamin D target proteins, as well as the functional significance of proteins involved in the transport and metabolism of vitamin D. Studies using these mice have played an increasingly important role in elucidating the mechanisms involved in the control of calcium homeostasis and have provided evidence for a role of vitamin D in extraskeletal health.

Sepiapterin reductase mediates chemical redox cycling in lung epithelial cells.

In the lung, chemical redox cycling generates highly toxic reactive oxygen species that can cause alveolar inflammation and damage to the epithelium, as well as fibrosis. In this study, we identified a cytosolic NADPH-dependent redox cycling activity in mouse lung epithelial cells as sepiapterin reductase (SPR), an enzyme important for the biosynthesis of tetrahydrobiopterin. Human SPR was cloned and characterized.

Treatment outcomes in 23 thoracic primitive neuroectodermal tumours: a retrospective study.

Objectives: Thoracic primitive neuroectodermal tumour is an aggressive malignancy with poor survival despite multimodality treatment regimens. Early diagnosis of the tumour by histological, immunohistochemical, ultrastructural and cytogenetic techniques and early total surgical resection of the tumour with intensive chemoradiation may improve outcomes.

Methods: Over 30 years, 23 patients (median age 29.

Isolation of multilineage progenitors from mouse brain.

Stem cells are unique cell populations with the ability to undergo self-renewal and differentiation. These cells have been identified in a wide range of tissues and possess varied differentiation potentials. Tissue-specific stem cells have typically been thought to have limited differentiation capabilities.

Alternative cleavage and polyadenylation: the long and short of it.

Cleavage and polyadenylation (C/P) of nascent transcripts is essential for maturation of the 3' ends of most eukaryotic mRNAs. Over the past three decades, biochemical studies have elucidated the machinery responsible for the seemingly simple C/P reaction. Recent genomic analyses have indicated that most eukaryotic genes have multiple cleavage and polyadenylation sites (pAs), leading to transcript isoforms with different coding potentials and/or variable 3' untranslated regions (UTRs).