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We previously reported that nanoceria can slow retinal degeneration in the tubby mouse for two weeks by multiple systemic injections. However, the long-term protection of retinal structure and function by directly deliver of nanoceria to the eye had not been explored. In this study, 172 ng of nanoceria in lμl saline (1 mM) were intravitreally injected into tubby P7 pups and assays were performed at P28, P49, P80 and P120. The expression of antioxidant associated genes and photoreceptor-specific genes were significantly up regulated, the mislocalization of rod and cone opsins was decreased, and retinal structure and function were protected. These findings demonstrate that nanoceria can function as catalytic antioxidants in vivo and may be broad spectrum therapeutic agents for multiple types of ocular diseases.

Ambulatory blood pressure monitoring (ABPM) is an accurate method for evaluating hypertension, yet its use in clinical practice may be limited by availability, cost, and patient inconvenience. The objective of this study was to investigate the ability of a 6-hour ABPM window to predict blood pressure control, based on that of the full 24-hour ABPM session across several clinical indications in a cohort of 486 patients referred for ABPM. Sensitivities and specificities of the 6-hour systolic blood pressure mean to accurately classify patients as hypertensive were determined using a fixed reference point of 130 mmHg for the 24-hour mean. For four common indications in which ABPM was ordered, prediction tables were constructed varying the thresholds for the 6-hour mean to find the optimal value that best predicted the 24-hour hypertensive status as determined from the full 24-hour interval. Using a threshold of 137 mmHg for the indications of borderline hypertension, evaluation of current antihypertensive regimen and suspected white-coat hypertension, sensitivity and specificity ranged from 0.83–0.88 and 0.80–0.88, respectively, for the ability of 6-hour ABPM to correctly categorize hypertensive status. Using 133 mmHg as the threshold for treatment resistance resulted in a sensitivity and specificity of 0.93 and 0.83, respectively. We conclude that a shortened ABPM session of 6 hours can be used to accurately classify blood pressure as controlled or not, based on the results of a 24-hour session. The optimal 6-hour threshold for comparison depends upon indication for referral.

The light-dependent subcellular translocation of rod alpha-transducin (GNAT-1, or rod Talpha) has been well documented. In dark-adapted animals, rod Talpha (rTalpha) is predominantly located in the rod outer segment (ROS) and translocates into the rod inner segment (RIS) upon exposure to the light. Neither the molecular participants nor the mechanism(s) involved in this protein trafficking are known. We hypothesized that other proteins must interact with rTalpha to affect the translocations. Using the MBP-rTalpha fusion pulldown assay, the yeast two-hybrid assay and the co-immunoprecipitation assay, we identified glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and rTalpha as interacting proteins. Immunoprecipitation also showed beta-actin associates with rTalpha in the dark but not in the light. To further investigate the involvement of GAPDH in light-induced rod Talpha translocation, GAPDH mRNA was knocked down in vivo by transient expression of siRNAs in rat photoreceptor cells. Under completely dark- and light-adapted conditions, the translocation of rTalpha was not significantly different within the 'GAPDH knock-down photoreceptor cells' compared to the non-transfected control cells. However, under partial dark-adaptation, rTalpha translocated more slowly in the 'GAPDH knock-down cells' supporting the conclusion that GAPDH is involved in rTalpha translocation from the RIS to the ROS during dark adaptation.

Neovascular ocular diseases (age-related macular degeneration, retinopathy of prematurity, and diabetic retinopathy) are the leading causes of blindness and are characterized by excessive new blood vessels either as choroidal neovascularization (CNV) or retinal neovascularization (RNV) which can be induced by the imbalance of growth factors. Animal models for these diseases provide valuable tools for studying the pathology, physiology, and mechanisms by which genes function and regulate these disease phenotypes. In this paper, we will review some recent studies using animal models and therapeutic treatments of these diseases.

Light-induced translocation of rod alpha-transducin (rTalpha, GNAT1) has been recognized as one of the mechanisms for light adaptation in rods. However, cone alpha-transducin (cTalpha, GNAT2) has not been shown to have such light-dependent redistribution. To investigate potential reasons for the restriction of cTalpha to the cone outer segment, the authors established a transient transgenic strategy to express cone Talpha within rod photoreceptor cells, and the location of the cone Talpha within rods and cones was examined under different light conditions.Vector DNA that expresses cTalpha and green fluorescent protein (GFP) bicistronically under control of the cytomegalovirus (CMV) promoter was injected subretinally into the eyes of neonatal rats, and this was followed by electroporation. The localization of cTalpha in rods and cones under different light conditions was determined by immunofluorescent techniques.Injection of the cDNA constructs resulted in the successful transient transfection of retinal cells. When cTalpha was exogenously expressed in rods, its localization paralleled that of endogenous rTalpha under light and dark conditions. Further experiments, with higher intensity light (7000 lux), demonstrated that endogenous cTalpha can also translocate in cone photoreceptor cells to the same extent it does in rods under 600 lux light.The authors successfully established an in vivo transient retinal transfection model. The demonstration of cTalpha translocation in rods indicates cTalpha is not inherently prevented from translocating. The novel observation of cTalpha translocation under high-intensity light suggests a light threshold regulates the redistribution of cTalpha possibly as a protective response against very bright light.

To determine the temporal kinetics of the simultaneous translocation of arrestin and rod alpha-transducin in mice exposed to different lighting environments and to compare the subcellular compartmentation of cone alpha-transducin with arrestin.Double labeling immunofluorescence microscopy and image analysis are used to visualize and quantify the concentrations of rod arrestin and alpha-transducin in the subcellular compartments of the rod outer segments, the rod inner segments and the synaptic terminals.The magnitude of the effects of the translocation are clearly contrasted in images of the retinas of animals that have been maximally light adapted verses retinas that have been maximally dark adapted. The onset of light results in a rapid, simultaneous, translocation of arrestin and alpha-transducin from their respective compartments (alpha-transducin in the rod outer segment and arrestin in the rod inner segment) to the opposite compartment. Almost all of alpha-transducin has translocated in less than two min whereas the translocation of the majority of arrestin requires at least five to six min. Translocation in the opposite direction, from light to dark, occurs more slowly for both proteins with arrestin requiring almost 30 min and alpha-T needing more than 200 min to complete its journey. Under the same lighting conditions, cone arrestin translocation is incomplete. Cone alpha-transducin does not translocate under any the lighting conditions tested. Unlike the frog, continuous exposure of mice to light does not result in arrestin translocating back to the rod inner segment.These data suggest that there are four mechanisms involved in the translocation of these two proteins. They also support the conclusion that the more important cellular function of the translocation process is to terminate phototransduction in rod and cone photoreceptors, which could provide protection against light damage. The secondary function of translocation is to maximize rod sensitivity to light during dark adaptation. The restricted localization of cone alpha-transducin to the cone outer segment is consistent with the function of cones in bright light, just as the concentration of rod alpha-transducin in dark adapted rod outer segment is consistent with their functioning in dim light.

To determine whether pigment epithelium-derived factor (PEDF) exhibits neurotrophic and neuroprotective activities in vivo for photoreceptor cells.Sprague-Dawley albino rats were injected intravitreally with 2 microg PEDF or a mixture of 1 microg basic fibroblast growth factor (bFGF)/1 microg PEDF in a volume of 1 microl phosphate-buffered saline (PBS). Animals were exposed to constant light for different periods at an illuminance level of 1200 to 1500 lux. The electroretinogram (ERG) waveforms of both eyes in the same animal were simultaneously recorded to evaluate functional protection. The morphologic protection was evaluated by quantitative histology.Intravitreal injection of PEDF before exposure to constant light resulted in significant morphologic and functional protection of photoreceptor cells in the retina of light-damaged rats. This protection depended on the duration and severity of light damage. The protection was eliminated by extending the light exposure to 10 days. Injection of PEDF at 0, 1, and 2 days after constant light exposure did not provide significant protection above that seen in PBS-injected eyes. Combination of PEDF with bFGF improved functional protection of photoreceptor cells.The data demonstrate that PEDF protected photoreceptor cells against light damage. This is significant, because it may open new avenues for the study of molecular mechanisms underlying degenerative processes. This, in turn, may lead to the development of therapeutic strategies for the prevention and treatment of degenerative diseases of the retina.

The 1,852,442-bp sequence of an M1 strain of Streptococcus pyogenes , a Gram-positive pathogen, has been determined and contains 1,752 predicted protein-encoding genes. Approximately one-third of these genes have no identifiable function, with the remainder falling into previously characterized categories of known microbial function. Consistent with the observation that S. pyogenes is responsible for a wider variety of human disease than any other bacterial species, more than 40 putative virulence-associated genes have been identified. Additional genes have been identified that encode proteins likely associated with microbial “molecular mimicry” of host characteristics and involved in rheumatic fever or acute glomerulonephritis. The complete or partial sequence of four different bacteriophage genomes is also present, with each containing genes for one or more previously undiscovered superantigen-like proteins. These prophage-associated genes encode at least six potential virulence factors, emphasizing the importance of bacteriophages in horizontal gene transfer and a possible mechanism for generating new strains with increased pathogenic potential.

Pigment epithelium-derived factor (PEDF), a 50-kDa glycoprotein, was first isolated from medium conditioned by human fetal retinal pigment epithelial (RPE) cells and was shown to be made in vivo by both fetal and adult RPE cells. After release from the RPE, PEDF binds to the glycosaminoglycans of the interphotoreceptor matrix,1,2 placing it in a prime physical location to affect the underlying neural retina. The PEDF gene has been cloned, sequenced and shown to have a tight linkage with a retinitis pigmentosa locus (RP13) on chromosome 17pl3.3 making it a candidate gene for this form of retinal degeneration.3,4 It has been reported that PEDF supported normal development of photoreceptor neurons and opsin expression after retinal pigment epithium removal.5 PEDF acts as a survival factor for cultured cerebellar granule cells,6, 7, 8 spinal motor neurons,9,10 hippocampal neurons11 and recently we demonstrated the survival-promoting activity of PEDF on retinal neurons in vitro 12. In addition to its effects on neurons, PEDF is a potent anti-angiogenesis factor,13 and is considered as a key coordinator of retinal neuronal and vascular functions.14 However, the role of PEDF as a neuroprotective factor in the retina and its association with specific retinal degenerative diseases are still being elucidated. The aim of the present research is to examine whether PEDF can prevent or delay photoreceptor degeneration. Using H2O2-induced cell death in cultured retinal neurons as in vitro model and the light-dependent degeneration of rat photoreceptor cells as in vivo model, our data demonstrate that PEDF results in significant protection of photoreceptor cells.

Pharmacist-physician comanagement of hypertension has been shown to improve office blood pressures (BPs). We sought to describe the effect of such a model on 24-hour ambulatory BPs.We performed a prospective, cluster-randomized, controlled clinical trial, enrolling 179 patients with uncontrolled hypertension from 5 primary care clinics in Iowa City, Iowa. Patients were randomized by clinic to receive pharmacist-physician collaborative management of hypertension (intervention) or usual care (control) for a 9-month period. In the intervention group, pharmacists helped patients to identify barriers to BP control, counseled on lifestyle and dietary modifications, and adjusted antihypertensive therapy in collaboration with the patients' primary care providers. Patients were seen by pharmacists a minimum of every 2 months. Ambulatory BP was measured at baseline and at study end.Baseline and end-of-study ambulatory BP profiles were evaluated for 175 patients. Mean (SD) ambulatory systolic BPs (SBPs), reported in millimeters of mercury, were reduced more in the intervention group than in the control group: daytime change in (Δ) SBP, 15.2 (11.5) vs 5.5 (13.5) (P .001); nighttime ΔSBP, 12.2 (14.8) vs 3.4 (13.3) (P .001); and 24-hour ΔSBP, 14.1 (11.3) vs 5.5 (12.5) (P .001). More patients in the intervention group than in the control group had their BP controlled at the end of the study (75.0% vs 50.7%) (P .001), as defined by overall 24-hour ambulatory BP monitoring.Pharmacist-physician collaborative management of hypertension achieved consistent and significantly greater reduction in 24-hour BP and a high rate of BP control. Trial Registration clinicaltrials.gov Identifier: NCT00201045.