Hartnup disease. Clinical, pathological, and biochemical observations

Hartnup disease is a rare genetic disorder of amino acid transport associated with variable and intermittent clinical abnormalities. A family is described in which three siblings had an intermittently progressive neurological disease and two of the affected siblings had the Hartnup-pattern aminoaciduria. Neuropathological examination of one case showed severe diffuse atrophy, generalized neuronal loss in the cortex, and Purkinje cell loss in the cerebellum. In vivo and in vitro studies of intestinal amino acid transport in the surviving sibling indicated a partial defect in the transport of several neutral amino acids (tryptophan, alanine, serine, and methionine) with normal transport of other neutral amino acids (threonine, phenylalanine, histidine, tyrosine, and isoleucine). Transport of glycine, proline, hydroxyproline, and the basic amino acids appeared normal.     

Continuous dynamic monitoring of pressure and flow patterns during assisted ventilation

On curettage, done in a 39 year old patient because of metorrhagia, a peanut-sized nodule was scraped away from the endometrium. Histologically it consisted of a jumble of irregularly shaped portions of normal appearing embryonal cartilage, of tortuous thick-walled vessels, of twisted bundles of nerves of ducts of respiratory and intestinal epithelium, and of sheets of hornifying skin. The haphazard disarray of tissues supported the notion that the lesion was not a remnant of a malformed embryo. Step-sections through the lesion revealed no traces of placental villi or decidua in the surrounding endometrium. The following were considered as possible origins of the teratoma: 1. displaced germinal cells, 2. retention of pluripotent müllerian epithelium, 3. overaged or blighted ovum. The latter seems most compatible with the histological findings.     

Copper oxide nanoparticle mediated DNA damage in terrestrial plant models

Engineered nanoparticles, due to their unique electrical, mechanical, and catalytic properties, are presently found in many commercial products and will be intentionally or inadvertently released at increasing concentrations into the natural environment. Metal- and metal oxide-based nanomaterials have been shown to act as mediators of DNA damage in mammalian cells, organisms, and even in bacteria, but the molecular mechanisms through which this occurs are poorly understood. For the first time, we report that copper oxide nanoparticles induce DNA damage in agricultural and grassland plants. Significant accumulation of oxidatively modified, mutagenic DNA lesions (7,8-dihydro-8-oxoguanine; 2,6-diamino-4-hydroxy-5-formamidopyrimidine; 4,6-diamino-5-formamidopyrimidine) and strong plant growth inhibition were observed for radish (Raphanus sativus), perennial ryegrass (Lolium perenne), and annual ryegrass (Lolium rigidum) under controlled laboratory conditions. Lesion accumulation levels mediated by copper ions and macroscale copper particles were measured in tandem to clarify the mechanisms of DNA damage. To our knowledge, this is the first evidence of multiple DNA lesion formation and accumulation in plants. These findings provide impetus for future investigations on nanoparticle-mediated DNA damage and repair mechanisms in plants.     

Subdiaphragmatic and intrathoracic paraspinal malignant peripheral nerve sheath tumors: a clinicopathologic study of 25 patients and 26 tumors

BACKGROUND: To determine the effects of anatomic site on the presentation and diagnosis of malignant peripheral nerve sheath tumors (MPNSTs) and on the treatment and outcomes of the patients, the authors initiated a study of these tumors at different sites. An earlier report described MPNSTs of the buttock and lower extremity, and the current series analyzes those presenting at intrathoracic (IT) and subdiaphragmatic (SD) paraspinal sites. METHODS: The authors reviewed data on patients with paraspinal MPNSTs who were seen at Memorial Hospital during the period 1960-1995 and for whom histologic slides were available. Various clinicopathologic parameters and their effects on patient outcomes were examined. RESULTS: Twenty-five patients with 26 tumors were evaluated. Seven tumors were IT and 19 were SD; 60% of the patients had neurofibromatosis type 1 (NF1). Most patients presented with pain, and a diagnostic delay (of 3 months to 2 years) was often noted. Mean tumor sizes for SD and IT tumors were 14.3 cm and 6.6 cm, respectively. Most MPNSTs were composed of spindle cells in fascicles. Twenty-seven percent exhibited divergent differentiation. Twenty-four tumors were high grade, and a low grade component was identified in 8 tumors. Surgical resection was attempted for 23 tumors (88%), but complete resection was achieved in only 6 cases (23%). Eighty percent of the patients died of their tumors, 2-year and 5-year survival rates were 35% and 16%, and median survival was 8.5 months. Significant prognostic factors were tumor size <5 cm, the presence of a low grade component, and complete tumor resection. CONCLUSIONS: Paraspinal MPNSTs have more aggressive behavior than peripherally located tumors, mainly because of the difficulty encountered in resecting them completely. Prognoses of patients with MPNST at this site appear to be affected by resection status, tumor size, and tumor grade.     

Malondialdehyde and 4-hydroxy-2-nonenal in plant tissue cultures: LC-MS determination of 2,4-dinitrophenylhydrazone derivatives

The cytologically active secondary lipid peroxidation products, malondialdehyde (MDA) and 4-hydroxy-2-nonenal (HNE) have been detected as their 2,4-dinitrophenylhydrazone (DNP) derivatives in plant tissue cultures using LC-MS. This paper reports, for the first time, the use of LC-MS methodology to definitively identify 4-hydroxy-2-nonenal in plants. Limits of detection for the two derivatives are approximately 5 pmol (1.2 x 10(-9) g; 1 microM) and 0.1 pmol (3 x 10(-11) g; 20 nM) respectively. Mass spectrometer response was linear in the range from 2-200 microM DNP-MDA and 0.02-10 microM DNP-HNE. This methodology has been used to assess the formation of aldehydic secondary lipid peroxidation products in dedifferentiated callus cultures of Daucus carota. The finding that profiles of MDA and HNE can be correlated with embryogenic competence is of considerable interest as oxidative status has already been implicated as a regulatory factor in animal development.     

Detecting Fluvial Wood in Forested Watersheds using LiDAR Data: A Methodological Assessment

It has long been known that large wood in rivers increases channel complexity and is a primary driver of geomorphic change in forested mountain streams in the Pacific Northwest. Studies analyzing the presence and distribution of fluvial wood are often limited in their spatial extents to the site or reach scales because of the intensive fieldwork required for comprehensive wood surveys. Remote sensing techniques are beginning to allow researchers to assess fluvial wood dynamics and distributions on a basin or regional scale. We used 2009 high‐resolution light detection and ranging (LiDAR) point cloud data to detect and quantify wood within five forested watersheds in the Oregon Coast Range. We filtered the LiDAR data to remove the forest canopy over the stream channel and visually inventoried fluvial wood based on its distinct shape within the channels. We derived several wood and stream morphometric variables to test theories relating to wood abundance and positioning in the lower reaches of streams. We were able to detect fluvial wood with confidence; however, validation of results with ground‐truth data was difficult in the study due to the dynamic and mobile nature of wood through time. We mapped a total of 163 single logs and 55 logjams within the five study watersheds. We did not find statistically significant differences between individual pieces and jam positioning in relation to slope; however, the surveyed wood was often found in areas of lower stream power. This research shows that it is possible to use height‐filtered LiDAR to detect in‐stream wood in densely forested watersheds and has the potential to be employed in future wood studies across broad spatial scales. Copyright © 2015 John Wiley & Sons, Ltd.