Hair dryer use to optimize pulsed dye laser treatment in rosacea patients

Rosacea is a common chronic inflammatory condition characterized by erythema, telangiectasias, papules, and pustules. While there are many effective treatment options for the papulopustular type, laser therapy remains the most effective modality to treat erythematotelangiectatic rosacea. Erythema and flushing associated with rosacea remains an uncomfortable and socially embarrassing problem for patients. Unfortunately, patients often do not have significant erythema or flushing when they present for laser treatment. With this in mind, we propose a novel technique aimed at enhancing the response of rosacea patients being treated for erythema with pulsed dye laser. Specifically, we present a split-face example of our clinical observation that pre-treatment with forced heated air prior to pulsed-dye laser leads to a greater response in rosacea patients with erythema and flushing.     

Proportion of patients in the Uganda rheumatic heart disease registry with advanced disease requiring urgent surgical interventions

Introduction

Since the establishment of the Uganda Rheumatic Heart Registry, over 900 patients have been enrolled. We sought to stratify the patients in the registry according to disease severity and optimal management strategy.

Methods

We reviewed data of 618 patients who had enrolled in the Registry between March 2010 and February 2013. The 67 patients who had died were excluded leaving 551 patients who were recruited. The optimum management strategy was determined according to the 2012 European Society of Cardiology guidelines on the management of valvular heart disease.

Results

Out of the 551 patient''s records evaluated, 398 (72.3%) required invasive intervention, with 332(60.3%) patients requiring surgery and 66 (12.0%) requiring percutaneous mitral commissurotomy (PMC). This leaves only 27.7% of patients who required only medical management. Currently, majority of the patients (498, 90.4%) in the registry are on medical treatment. Of the 60.3% requiring surgical intervention, only 8.0% (44 patients) underwent valvular surgery and 5(1.0%) patients of the 66 (12.0%) underwent PMC successfully.

Conclusion

There is a high proportion of patients with severe disease that require surgical treatment yet they cannot access this therapy due to absence of local expertise.     

Defects in 8-oxo-guanine repair pathway cause high frequency of C > A substitutions in neuroblastoma

Neuroblastomas are childhood tumors with frequent fatal relapses after induction treatment, which is related to tumor evolution with additional genomic events. Our whole-genome sequencing data analysis revealed a high frequency of somatic cytosine > adenine (C > A) substitutions in primary neuroblastoma tumors, which was associated with poor survival. We showed that increased levels of C > A substitutions correlate with copy number loss (CNL) of OGG1 or MUTYH. Both genes encode DNA glycosylases that recognize 8-oxo-guanine (8-oxoG) lesions as a first step of 8-oxoG repair. Tumor organoid models with CNL of OGG1 or MUTYH show increased 8-oxoG levels compared to wild-type cells. We used CRISPR-Cas9 genome editing to create knockout clones of MUTYH and OGG1 in neuroblastoma cells. Whole-genome sequencing of single-cell OGG1 and MUTYH knockout clones identified an increased accumulation of C > A substitutions. Mutational signature analysis of these OGG1 and MUTYH knockout clones revealed enrichment for C > A signatures 18 and 36, respectively. Clustering analysis showed that the knockout clones group together with tumors containing OGG1 or MUTYH CNL. In conclusion, we demonstrate that defects in 8-oxoG repair cause accumulation of C > A substitutions in neuroblastoma, which contributes to mutagenesis and tumor evolution.

Neuroblastoma is a childhood tumor of the peripheral sympathetic nervous system that accounts for 15% of childhood cancer mortality (1). Survival rates vary between spontaneous remissions in the low-stage neuroblastoma tumors to less than 50% survival in the high-stage patient group (2). Like other pediatric cancer types, the number of somatic mutations in neuroblastoma is relatively low compared to adult cancers (3). Relapsed neuroblastoma tumors have an increased mutational burden compared to primary tumors and show recurrent alterations in, e.g., the RAS-MAPK pathway (4, 5).Over the last years, substitution patterns and mutational signatures have been investigated in adult and pediatric cancer types (3, 6, 7). These mutational signatures are characteristic combinations of substitutions in the context of neighboring bases (6). For some of these mutational signatures, the underlying mutational process has been described, while it is unknown for others (6, 8). In the majority of pediatric cancer types, cytosine > thymine substitutions are most abundant, which has been linked to spontaneous deamination of 5-methyl-cytosines and mutational signature 1 (3). Several studies reported a higher frequency of cytosine > adenine (C > A) substitutions in neuroblastoma (3, 7). C > A mutations can result from defects in 8-oxo-guanine (8-oxoG) repair (9). 8-oxoG is one of the most abundant DNA lesions generated by reactive oxygen species (10–12). 8-oxoG can base pair with both a cytosine (C) and an adenine (A). During replication, DNA polymerases can therefore insert an incorrect A opposite of 8-oxoG. In the next round of replication, a thymine (T) will be inserted opposite the A, finally resulting in a C > A substitution (13, 14). To combat reactive oxygen species–induced DNA damage, 8-oxoG can be recognized by the DNA glycosylases OGG1 and MUTYH when it forms a base pair with a C or A, respectively. 8-oxoG repair is initiated by excision of 8-oxoG by OGG1 or excision of the wrongly inserted A opposite 8-oxoG by MUTYH (Fig. 1). In addition, NUDT1 prevents incorporation of 8-oxo-dGTP from the free nucleotide pool, by hydrolysis of 8-oxo-dGTP to 8-oxo-GMP, which cannot be incorporated (13, 15, 16).Open in a separate windowFig. 1.Schematic overview of 8-oxoG repair pathway. When a G in the DNA is oxidized to an 8-oxo-guanine [8-oxoG(8)], the replicative DNA polymerases will insert an A opposite of the 8-oxoG during replication. In the next round of replication, a T will be inserted opposite of the A, resulting in a C > A substitution. The DNA glycosylases OGG1 and MUTYH are able to recognize 8-oxoG base pairing with a C or A, respectively. OGG1 excises 8-oxoG from the DNA, while MUTYH excises the A opposite of the 8-oxoG. The DNA is further repaired by the base excision repair pathway to a C:G base pair for OGG1-initiated repair or to a C:8-oxoG for MUTYH-initiated repair. This C:8-oxoG base pair is then again a substrate for OGG1. In addition, NUDT1 prevents the incorporation of 8-oxo-dGTP into the DNA, by hydrolyzing 8-oxo-dGTP, from the free nucleotide pool, to 8-oxo-dGMP.In this study, we identify increased accumulation of C > A substitutions in high-risk neuroblastoma, resulting in a strong contribution of mutational signature 18 and 36 in these tumors. We show that neuroblastoma tumors with high C > A substitution frequencies were enriched for copy number loss (CNL) of OGG1 and MUTYH. To mimic this phenotype, we used CRISPR-CAS9 to engineer defects in the 8-oxoG repair genes OGG1 and MUTYH in neuroblastoma cells, resulting in an increased accumulation of C > A substitutions in single-cell knockout clones and a high contribution of C > A mutational signatures 18 and 36. In clustering analysis, these clones group together with neuroblastoma tumors with OGG1 or MUTYH CNL. Finally, we evaluated a neuroblastoma relapse cohort and identified that 47% of alterations in RAS-MAPK pathway genes were caused by C > A substitutions. Taken together, our study identifies that defects in the 8-oxoG repair pathway cause an accumulation of C > A substitutions in neuroblastoma tumors, potentially leading to increased adaptive capacity and tumor evolution.     

Effect of pH on the stability of kidney injury molecule 1 (KIM-1) and on the accuracy of its measurement in human urine

BackgroundUrinary KIM-1 is a novel biomarker for tubular kidney damage, however little is known about its stability. The goal of this study is to examine the effect of urinary pH on the stability of KIM-1.MethodsUrine samples were collected from 45 volunteers. Samples were aliquoted, adapted to different pH values (range 4 to 9) and stored at ?80 °C. After thawing, each aliquot was divided into two, of which one was used to measure KIM-1 (human tim-1/kim-1/Havcr Elisa kit; R&D systems) at the same pH at which it was stored, while the other was readapted to pH 7 before measurement.ResultsKIM-1 values of aliquots of the same sample are stable when stored at pH 6, 7 and 8 whereas at lower and higher storage pH, KIM-1 levels decrease significantly. When samples are readjusted to a neutral pH just before KIM-1 measurement, there are no longer significant differences between KIM-1 in aliquots stored at different pH values.ConclusionsNo effect of urinary pH on the stability of KIM-1 was seen. However, the only commercially available human tim-1/kim-1/Havcr Elisa kit of RD systems is pH dependent and we therefore suggest samples should be adjusted to neutral pH before measurement.     

Overexpression of the oncogenic signal transducer Gab2 occurs early in breast cancer development

Gab2, a docking‐type signaling protein with demonstrated oncogenic potential, is overexpressed in breast cancer, but its prognostic significance and role in disease evolution remain unclear. Immunohistochemical detection of Gab2 in a large cohort of primary human breast cancers of known outcome revealed that while Gab2 expression was positively correlated with increased tumor grade, it did not correlate with disease recurrence or breast cancer‐related death in the total cohort or in patients stratified according to lymph node, estrogen receptor (ER) or HER2 status. Interestingly, analysis of a “progression series” that included premalignant and preinvasive breast lesions as well as samples of metastatic disease revealed that Gab2 expression was significantly enhanced in the earliest lesion examined, usual ductal hyperplasia, with a further increase detected in ductal carcinoma in situ (DCIS). Furthermore, expression was less in invasive cancers and lymph node metastases than in DCIS, but still higher than in normal breast. These findings indicate that while Gab2 expression is not prognostic in breast cancer, its role in early disease evolution warrants further analysis, as Gab2 and its effectors may provide targets for novel strategies aimed at preventing breast cancer development.