Stereological estimation of Weibel-Palade bodies in the retinal vasculature of normal and diabetic dogs

The absolute volume of Weibel-Palade (WP) bodies, the storage organelles of von Willebrand factor (vWF), was estimated by a stereological method in a known volume of central retina from normal and 5-year diabetic dogs. The results showed that the volume of WP bodies present in the endothelium of the retinal vasculature varies with blood vessel type and in diabetes. In both diabetic and normal dogs the endothelium of the retinal veins contained a higher volume of WP bodies than that of the retinal arteries. In dogs which had been diabetic for a duration of 5 years the volume of WP bodies present in the endothelium of retinal veins was significantly greater than in the endothelium of veins from the control animals. However, there was no significant difference in the volume of WP bodies present in the endothelium of retinal arteries or capillaries between the two groups of animals.

A morphologic and autoradiographic study of cell death and regeneration in the retinal microvasculature of normal and diabetic rats

Cell loss and regeneration were investigated and compared in the retinal microvasculature of age- and sex-matched normal and streptozotocin diabetic rats. Selective pericyte loss in the diabetic rat was characterized by changes in the pericyte to endothelial cell ratio in retinal capillaries isolated for microscopy by the trypsin digest technique. A comparison of 3- and 9-month-old normal rats showed no significant change in the pericyte to endothelial cell ratio (1:2.7). In diabetic animals the ratio was reduced to 1:4.03, which was statistically significant (P less than .001). Premitotic retinal vascular cells in normal and diabetic rats were labelled with tritiated thymidine and the labelling indices calculated from cell counts of trypsin digest preparations. Methyl H3 thymidine was infused continuously over an eight-day period using osmotic mini pumps. The labelling index of endothelial cells (0.33%) in normal rats increased to 0.91% in diabetic animals (P less than .05). The labelling index of pericyte cells in normal animals (0.16%) did not increase significantly (P greater than .05) in diabetic animals (0.19%). A special stain was used to exclude labelled polymorphonuclear leukocytes from the cell counts.

A spectroscopically normal type Ic supernova from a very massive progenitor

We present observations of the Type Ic supernova (SN Ic) 2011bm spanning a period of about one year. The data establish that SN 2011bm is a spectroscopically normal SN Ic with moderately low ejecta velocities and with a very slow spectroscopic and photometric evolution (more than twice as slow as SN 1998bw). The Pan-STARRS1 retrospective detection shows that the rise time from explosion to peak was 40 days in the R band. Through an analysis of the light curve and the spectral sequence, we estimate a kinetic energy of 7-17 foe and a total ejected mass of 7-17 Mo, 5-10 Mo of which is oxygen and 0.6-0.7 Mo is 56Ni. The physical parameters obtained for SN 2011bm suggest that its progenitor was a massive star of initial mass 30-50 Mo. The profile of the forbidden oxygen lines in the nebular spectra show no evidence of a bi-polar geometry in the ejected material.

Spectroscopic Observations of SN 2012fr: A Luminous Normal Type Ia Supernova with Early High Velocity Features and Late Velocity Plateau

We present 65 optical spectra of the Type Ia supernova SN 2012fr, of which 33 were obtained before maximum light. At early times SN 2012fr shows clear evidence of a high-velocity feature (HVF) in the Si II 6355 line which can be cleanly decoupled from the lower velocity "photospheric" component. This Si II 6355 HVF fades by phase -5; subsequently, the photospheric component exhibits a very narrow velocity width and remains at a nearly constant velocity of v~12,000 km/s until at least 5 weeks after maximum brightness. The Ca II infrared (IR) triplet exhibits similar evidence for both a photospheric component at v~12,000 km/s with narrow line width and long velocity plateau, as well as a high-velocity component beginning at v~31,000 km/s two weeks before maximum. SN 2012fr resides on the border between the "shallow silicon" and "core-normal" subclasses in the Branch et al. (2009) classification scheme, and on the border between normal and "high-velocity" SNe Ia in the Wang et al. (2009a) system. Though it is a clear member of the "low velocity gradient" (LVG; Benetii et al., 2005) group of SNe Ia and exhibits a very slow light-curve decline, it shows key dissimilarities with the overluminous SN 1991T or SN 1999aa subclasses of SNe Ia. SN 2012fr represents a well-observed SN Ia at the luminous end of the normal SN Ia distribution, and a key transitional event between nominal spectroscopic subclasses of SNe Ia.

Investigation of moisture condition and Autoclam sensitivity on air permeability measurements for both normal concrete and high performance concrete

While on site measurement of air permeability provides a useful approach for assessing the likely long term durability of concrete structures, no existing test method is capable of effectively determining the relative permeability of high performance concrete (HPC). Lack of instrument sensitivity and the influence of concrete moisture are proposed as two key reasons for this phenomenon. With limited systematic research carried out in this area to date, the aim if this study was to investigate the influence of instrument sensitivity and moisture condition on air permeability measurements for both normal concrete and HPC. To achieve a range of moisture conditions, samples were dried initially for between one and 5 weeks and then sealed in polythene sheeting and stored in an oven at 50 C to internally distribute moisture evenly. Moisture distribution was determined throughout using relative humidity probe and electrical resistance measurements. Concrete air permeability was subsequently measured using standardised air permeability (Autoclam) and water penetration (BS EN: 12390-8) tests to assess differences between the HPCs tested in this study. It was found that for both normal and high performance concrete, the influence of moisture on Autoclam air permeability results could be eliminated by pre-drying (50 ± 1 C, RH 35%) specimens for 3 weeks. While drying for 5 weeks alone was found not to result in uniform internal moisture distributions, this state was achieved by exposing specimens to a further 3 weeks of sealed pre-conditioning at 50 ± 1 C. While the Autoclam test was not able to accurately identify relative HPC quality due to low sensitivity at associated performance levels, an effective preconditioning procedure to obtain reliable air permeability of HPC concretes was identified. © 2013 The Authors

SN 2009N: linking normal and subluminous Type II-P Sne

We present ultraviolet, optical, near-infrared photometry and spectroscopy of SN 2009N in NGC 4487. This object is a Type II-P supernova with spectra resembling those of subluminous II-P supernovae, while its bolometric luminosity is similar to that of the intermediate-luminosity SN 2008in. We created SYNOW models of the plateau phase spectra for line identification and to measure the expansion velocity. In the near-infrared spectra we find signs indicating possible weak interaction between the supernova ejecta and the pre-existing circumstellar material. These signs are also present in the previously unpublished near-infrared spectra of SN 2008in. The distance to SN 2009N is determined via the expanding photosphere method and the standard candle method as D = 21.6 ± 1.1 Mpc. The produced nickel-mass is estimated to be ∼0.020 ± 0.004 M⊙. We infer the physical properties of the progenitor at the explosion through hydrodynamical modelling of the observables. We find the values of the total energy as ∼0.48 × 1051 erg, the ejected mass as ∼11.5 M⊙, and the initial radius as ∼287 R⊙.

Intravitreal Injection of Normal Saline Induces Retinal Degeneration in the C57BL/6J Mouse

Purpose: To investigate the adverse effect of intravitreal injection of normal saline (NS) and phosphate buffered saline (PBS) in mouse eyes.

Methods: NS or PBS was injected intravitreally into C57BL/6J mouse eyes. Retinal lesions were monitored by fundus imaging, spectral-domain optical coherence tomography (SD-OCT), and histological investigations. Retinal immune gene expression was determined by real-time polymerase chain reaction (PCR). The toxic effect of NS and PBS or retinal protein from NS- or PBS-injected eyes on retinal pigment epithelium (RPE) was tested in B6-RPE-07 mouse RPE cell cultures.

Results: Intravitreal injection of NS dose-dependently induced localized retinal lesion in mice. Histological investigations revealed multiple vacuoles in photoreceptor outer segments and RPE cells. The lesions recovered over time and by 3 weeks post injection the majority of lesions vanished in eyes receiving 1 μl NS. Inflammatory genes, including TNF-α, IL-1β, IL-6, iNOS, and VEGF were upregulated in NS injected eyes. Intravitreal injection of PBS did not cause any pathology. The treatment of B6-RPE07 cells with 30% PBS or 30% NS did not affect RPE viability. However, incubation of 1-μg/ml retinal protein from NS-injected eyes, but not PBS-injected eyes induced RPE cell death.

Conclusion: NS is toxic to the C57BL/6J mouse retina and should not be used as a vehicle for intraocular injection. PBS is not toxic to the retina and is a preferred vehicle.

Translational Relevance: NS is not a physiological solution for intraocular injection in the C57BL/6J mice and questions its suitability for intraocular injection in other species, including human.

DEK oncogene expression during normal hematopoiesis and in Acute Myeloid Leukemia (AML)

DEK is important in regulating cellular processes including proliferation, differentiation and maintenance of stem cell phenotype. The translocation t(6;9) in Acute Myeloid Leukemia (AML), which fuses DEK with NUP214, confers a poor prognosis and a higher risk of relapse. The over-expression of DEK in AML has been reported, but different studies have shown diminished levels in pediatric and promyelocytic leukemias. This study has characterized DEK expression, in silico, using a large multi-center cohort of leukemic and normal control cases. Overall, DEK was under-expressed in AML compared to normal bone marrow (NBM). Studying specific subtypes of AML confirmed either no significant change or a significant reduction in DEK expression compared to NBM. Importantly, the similarity of DEK expression between AML and NBM was confirmed using immunohistochemistry analysis of tissue mircorarrays. In addition, stratification of AML patients based on median DEK expression levels indicated that DEK showed no effect on the overall survival of patients. DEK expression during normal hematopoiesis did reveal a relationship with specific cell types implicating a distinct function during myeloid differentiation. Whilst DEK may play a potential role in hematopoiesis, it remains to be established whether it is important for leukemagenesis, except when involved in the t(6;9) translocation.

Low dose effects of ionizing radiation on normal tissue stem cells

In recent years, there has been growing evidence for the involvement of stem cells in cancer initiation. As a result of their long life span, stem cells may have an increased propensity to accumulate genetic damage relative to differentiated cells. Therefore, stem cells of normal tissues may be important targets for radiation-induced carcinogenesis.

Knowledge of the effects of ionizing radiation (IR) on normal stem cells and on the processes involved in carcinogenesis is very limited. The influence of high doses of IR (>5 Gy) on proliferation, cell cycle and induction of senescence has been demonstrated in stem cells. There have been limited studies of the effects of moderate (0.5–5 Gy) and low doses (<0.5 Gy) of IR on stem cells however, the effect of low dose IR (LD-IR) on normal stem cells as possible targets for radiation-induced carcinogenesis has not been studied in any depth. There may also be important parallels between stem cell responses and those of cancer stem cells, which may highlight potential key common mechanisms of their response and radiosensitivity.

This review will provide an overview of the current knowledge of radiation-induced effects on normal stem cells, with particular focus on low and moderate doses of IR.

Gene expression in normal Urothelium depends on location within the bladder:A possible link to bladder carcinogenesis

Objectives: Clinical studies have shown that more than 70% of primary bladder tumours arise in the area around the ureteric orifice. In this study a genomic approach was taken to explore the molecular mechanisms that may influence this phenomenon.

Methods: RNA was isolated from each individual normal ureteric orifice and the dome biopsy from 33 male patients. Equal amounts of the pooled ureteric orifice and dome mRNAs were labelled with Cy3 and Cy5, respectively before hybridising to the gene chip (UniGEM 2.0, Incyte Genomics Inc., Wilmington, Delaware, USA). Results: Significant changes (more than a twofold difference) in gene expression were observed in 3.1% (312) of the 10,176 gene array: 211 genes upregulated and 101 downregulated. Analysis of Cdc25B, TK1, PKM, and PDGFra with RT-PCR supported the reliability of the microarray result. Seladin-1 was the most upregulated gene in the ureteric orifice: 8.3-fold on the microarray and 11.4-fold by real time PCR.

Conclusions: Overall, this study suggests significant altered gene expression between these two anatomically distinct areas of the normal human bladder. Of particular note is Seladin-1, whose significance in cancer is yet to be clarified. Further studies of the genes discovered by this work will help clarify which of these differences influence primary bladder carcinogenesis. (c) 2006 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Adult cardiac fibroblast proliferation is modulated by calcium/calmodulin-dependent protein kinase II in normal and hypertrophied hearts

Increased adult cardiac fibroblast proliferation results in an increased collagen deposition responsible for the fibrosis accompanying pathological remodelling of the heart. The mechanisms regulating cardiac fibroblast proliferation remain poorly understood. Using a minimally invasive transverse aortic banding (MTAB) mouse model of cardiac hypertrophy, we have assessed fibrosis and cardiac fibroblast proliferation. We have investigated whether calcium/calmodulin-dependent protein kinase IIδ (CaMKIIδ) regulates proliferation in fibroblasts isolated from normal and hypertrophied hearts. It is known that CaMKIIδ plays a central role in cardiac myocyte contractility, but nothing is known of its role in adult cardiac fibroblast function. The MTAB model used here produces extensive hypertrophy and fibrosis. CaMKIIδ protein expression and activity is upregulated in MTAB hearts and, specifically, in cardiac fibroblasts isolated from hypertrophied hearts. In response to angiotensin II, cardiac fibroblasts isolated from MTAB hearts show increased proliferation rates. Inhibition of CaMKII with autocamtide inhibitory peptide inhibits proliferation in cells isolated from both sham and MTAB hearts, with a significantly greater effect evident in MTAB cells. These results are the first to show selective upregulation of CaMKIIδ in adult cardiac fibroblasts following cardiac hypertrophy and to assign a previously unrecognised role to CaMKII in regulating adult cardiac fibroblast function in normal and diseased hearts.