The gastrointestinal manifestation of constitutional mismatch repair deficiency syndrome: from a single adenoma to polyposis‐like phenotype and early onset cancer

Data on the clinical presentation of constitutional mismatch repair deficiency syndrome (CMMRD) is accumulating. However, as the extraintestinal manifestations are often fatal and occur at early age, data on the systematic evaluation of the gastrointestinal tract is scarce. Here we describe 11 subjects with verified biallelic carriage and who underwent colonoscopy, upper endoscopy and small bowel evaluation. Five subjects were symptomatic and in six subjects the findings were screen detected. Two subjects had colorectal cancer and few adenomatous polyps (19, 20 years), three subjects had polyposis‐like phenotype (13, 14, 16 years), four subjects had few adenomatous polyps (8, 12–14 years) and two subjects had no polyps (both at age 6). Of the three subjects in the polyposis‐like group, two subjects had already developed high‐grade dysplasia or cancer and one subject had atypical juvenile polyps suggesting juvenile polyposis. Three out of the five subjects that underwent repeated exams had significant findings during short interval. The gastrointestinal manifestations of CMMRD are highly dependent upon age of examination and highly variable. The polyps may also resemble juvenile polyposis. Intensive surveillance according to current guidelines is mandatory.     

PNist: interactive volumetric measurements of plexiform neurofibromas in MRI scans

Purpose

Volumetric measurements of plexiform neurofibromas (PNs) are time consuming and error prone, as they require the delineation of the PN boundaries, which is mostly impractical in the daily clinical setup. Accurate volumetric measurements are seldom performed for these tumors mainly due to their great dispersion, size and multiple locations. This paper presents a semiautomatic method for segmentation of PN from STIR MRI scans.

Methods

Plexiform neurofibroma interactive segmentation tool (PNist) is a new tool to segment PNs in STIR MRI scans. The method is based on histogram tumor models computed from a training set.

Results

Experimental results from 28 datasets show an average absolute volume difference of 6.8 % with an average user time of approximately 7 min versus more than 13 min with manual delineation. In complex cases, the PNist user time is less than half in compared to state-of-the-art tools.

Conclusions

PNist is a new method for the semiautomatic segmentation of PN lesions. Its simplicity and reliability make it unique among other state-of-the-art methods. It has the potential to become a clinical tool that allows the reliable evaluation of PN burden and progression.     

Mercury Speciation and Total Organic Carbon in Marine Sediments Along the Mediterranean Coast of Israel

Along the Israeli Mediterranean Coast, three areas are considered “hot spots” of mercury (Hg) pollution: (1) Northern Haifa Bay (NHB), (2) the lower Qishon River at the southern part of Haifa Bay, and (3) a marine outfall of activated sewage sludge at the southern coast off Palmachim (sewage-sludge disposal site [SDS]). Even though the total Hg (HgT) concentrations in the sediments at the three areas are of the same order of magnitude (250–500?μg?kg^?1), Hg was shown to bioaccumulate in fish and benthic fauna from Haifa Bay but not in benthic fauna or in commercial fish caught along the southern Mediterranean Coast of Israel near the SDS outfall. The primary goal of this study was to measure the concentrations of Hg species (HgT, methyl-Hg [MeHg], and Hg in different biogeochemical fractions)—in conjunction with organic carbon—in sediments of NHB and the lower Qishon River to assess its impact on Hg transitions among the species as characterized by different bioavailability and bioaccessibility. HgT concentrations in NHB and the Qishon River ranged from 249 to 347 and 165 to 667?μg?kg^?1, respectively. MeHg was significantly higher in the Qishon River (6.3–34.0?μg?kg^?1) than in NHB (0.22–0.70?μg?kg^?1) as were total organic carbon (TOC) concentrations (average 2.5 vs. 0.13?%). The relative Hg distribution in the biogeochemical fractions in NHB was 2.3?% in the most bioaccessible fractions (F1?+?F2), 55?% in the organo-chelated species fraction (F3), 42?% in the strong-complexed species fraction (F4), and 0.7?% in the mercuric-sulfide fraction (F5). In the Qishon River, the bioavailable F1?+?F2 and F3 fractions were lower than in NHB (<0.01 and 23?%, respectively) and the more refractory F4 and F5 fractions higher (73 and 3.3?%, respectively). The fractionation of Hg in Qishon River sediments was similar to the distribution found in polluted stations at the SDS. TOC and MeHg were positively and negatively correlated, respectively, in Qishon River and NHB sediments. Methylation depended on TOC availability when its concentration was in the range of 2–4 wt%. It is possible that TOC in the sediment controlled Hg speciation: Hg in F3 decreased and in F4 increased with increasing TOC concentrations. In contrast, MeHg/HgT was significantly positively correlated with TOC and Hg in the stable F4 fraction and negatively correlated with Hg in the F3 fraction. It was therefore assumed that higher TOC concentrations enhanced microbial activity and decomposition of organic matter. Hg was released from the F3 fraction and was either transferred to the F4 fraction or made available for methylation processes.     

Transcatheter aortic valve implantation of a CoreValve device using novel real-time imaging guidance

Thorough imaging of the aortic valve and related structures is highly important before and during transcatheter aortic-valve implantation. However, conventional aortography is limited for guiding precise valve placement and depends on contrast injections. A real-time imaging system capable of guiding the operator during Edwards-SPAIEN valve procedures has been introduced (C-THV, Paieon, Inc.). We describe the first application of the novel C-THV system during CoreValve implantation in a very challenging clinical scenario that required precise high implantation using minimal contrast.     

Measuring the red blood cell shape in capillary flow using spectrally encoded flow cytometry

Red blood cells in small capillaries exhibit a wide variety of deformations that reflect their true physiological conditions at these important locations. By applying a technique for the high-speed microscopy of flowing cells, termed spectrally encoded flow cytometry (SEFC), we image the light reflected from the red blood cells in human capillaries, and propose an analytical slipper-like model for the cell morphology that can reproduce the experimental in vivo images. The results of this work would be useful for studying the unique flow conditions in these vessels, and for extracting useful clinical parameters that reflect the true physiology of the blood cells in situ.