Ετικέτες

Τετάρτη 22 Νοεμβρίου 2017

Nodular Sclerodermatous Chronic Cutaneous Graft-Versus-Host Disease (GvHD): A New Clinicopathological Variant of Cutaneous Sclerodermatous GvHD Resembling Nodular/Keloidal Scleroderma

imageAbstract: Cutaneous chronic graft-versus-host disease (GvHD) has a broad spectrum of clinicopathological presentations, the most common ones being poikiloderma, lichen planus–like eruptions, lichen sclerosus–like lesions, morphea-like plaques, and deep sclerosis. New forms of chronic cutaneous GvHD with different clinicopathological characteristics have been described, most of them mimicking cutaneous manifestations of autoimmune diseases. We report the case of a 35-year-old man who underwent allogenic stem cell transplantation for a therapy-associated acute myeloid leukemia and developed an acute GvHD with involvement of skin and gastrointestinal tract. He subsequently presented with chronic sclerodermatous cutaneous GvHD, followed by the appearance of indurated erythematous papules and plaques located on his back, resembling the nodular/keloidal form of cutaneous scleroderma on both clinical and histopathological grounds. This peculiar clinicopathologic presentation of chronic cutaneous GvHD was never described previously.

http://ift.tt/2A19NjD

Bullous Pemphigoid: Use of C4d Immunofluorescent Staining in a Case With Repeated Negative Conventional Direct Immunofluorescence Studies

imageAbstract: Direct immunofluorescence (DIF) using frozen section material from a fresh/preserved perilesional biopsy is the gold standard for the immunopathologic diagnosis of bullous pemphigoid (BP). DIF in BP shows linear dermoepidermal junction (DEJ) staining for C3, with or without staining for IgG. In some situations, only a formalin-fixed lesional biopsy is obtained (with no fresh/preserved perilesional biopsy for DIF). In this setting, paraffin section C4d immunohistochemistry has proven to be diagnostically useful, demonstrating linear DEJ positivity for C4d. We present a novel use of C4d staining for the diagnosis of BP, specifically analyzing C4d perilesional frozen section DIF in a case where standard perilesional frozen section DIF for IgG/C3 was available, but was negative. An 80-year-old woman presented with a pruritic bullous lesion on her left upper extremity, clinically thought to represent BP. Lesional histologic findings were typical for BP, but perilesional frozen section DIF staining was negative for IgG and C3. A second set of biopsies processed at a different laboratory yielded the same result. A diagnosis of bullous scabies was considered. Subsequently, perilesional frozen section DIF for C4d was obtained, which showed strong linear DEJ positivity, confirming the diagnosis of BP. DIF for C4d is widely used in transplant pathology, since C4d is persistent in tissue, versus C3. Our case demonstrates that perilesional frozen section DIF staining for C4d may be positive and diagnostic in BP, even when conventional DIF staining for IgG and C3 is negative.

http://ift.tt/2zZoQKv

Annular Lichenoid Dermatitis (of Youth): Report of a Case With Lichen Planus-Like Features

imageAbstract: Annular lichenoid dermatitis of youth (ALDY), a dermatosis with peculiar clinical and pathological features, represents still a debated entity, given its similarity, among others, with mycosis fungoides. A case of ALDY in a 50-year-old male patient is reported. Clinically, the patient presented an oval scleroderma-like plaque on the right flank. Histology and immunohistochemistry showed the classic appearance described in ALDY. T-cell receptor rearrangement was absent. Interestingly, a focus consistent with lichen planus was observed. The lesion resolved with topical steroids and at a follow-up of 24 months no recurrence has been registered. The case described herein supports the hypothesis that ALDY is a reactive lichenoid dermatosis, closely related to lichen planus.

http://ift.tt/2A19w05

Ulcerating Tumor of the Scalp: Answer

No abstract available

http://ift.tt/2ApwgaH

Mucocutaneous Hyperpigmentation in a Patient With a History of Both Minocycline and Silver Ingestion

imageAbstract: Minocycline is a derivative of tetracycline. It has been widely used in dermatology for the treatment of acne and rosacea. One of its adverse effects is pigmentation of various body tissues. Clinically, 3 main distinct types of hyperpigmentation by minocycline have been distinguished: type I, with blue-gray to black pigment on the face in areas of scarring or inflammation; type II, with blue-gray pigment on normal skin of the legs, forearms and on the shins; and type III, with a diffuse muddy-brown discoloration in areas of sun exposure. In the current report, we present the case of a 50-year old man with a history of severe acne treated with minocycline in the past, who currently complained about discoloration of his face. He had also taken colloidal silver supplements for "good health" about 16 years ago. Physical examination revealed gray-blue discoloration on the face, sclera, hard palate and back. Histologic examination showed intracellular pigment deposits in macrophages of the superficial dermis in a perivascular and an interstitial distribution. The pigment stained with Fontana-Masson and von Kossa, whereas it was Perls' iron negative. This case does not fit well into any of the previously described patterns of minocycline-related hyperpigmentation.

http://ift.tt/2AnZxCu

Verrucous Plaque on the Abdomen: Answer

No abstract available

http://ift.tt/2zZInKL

Syringotropic Mycosis Fungoides: A Rare Form of Cutaneous T-cell Lymphoma Enabling a Histopathologic “Sigh of Relief”

imageAbstract: Syringotropic mycosis fungoides (STMF) is a very rare variant of cutaneous T-cell lymphoma. It follows a much milder disease course than its clinically indistinguishable adnexal counterpart, folliculotropic mycosis fungoides (FMF). We report a case of a 36-year-old man who presented with erythematous, studded papules and plaques on the left upper extremity and right anterior thigh diagnosed as mycosis fungoides (MF) Stage 1A on initial superficial shave biopsy. Lesions recurred after initial improvement with narrow-band ultraviolet light therapy demonstrating a concentration of abnormal lymphocytes around eccrine sweat glands on repeat biopsy consistent with STMF. Although the deeper, periadnexal infiltrate found in both STMF and FMF confers increased resistance to skin-directed therapies effective in classic MF, these entities diverge with respect to their clinical behavior. Syringotropism is a marker for increased disease-specific survival, whereas even FMF carries a prognosis worse than conventional MF. Increased awareness among the dermatopathology community of the histopathologic distinction between STMF and FMF is essential to guide treatment type, duration, and intensity in adnexal disease.

http://ift.tt/2zZoP9p

Giant Subcutaneous Solitary Gardner Fibroma of the Head of a Bulgarian Child

imageNo abstract available

http://ift.tt/2zY3NIn

Histopathologic Findings of Cutaneous Hyperpigmentation in Addison Disease and Immunostain of the Melanocytic Population

imageAbstract: The histopathological features of cutaneous hyperpigmentation in Addison disease have very occasionally been reported, and they include acanthosis, hyperkeratosis, focal parakeratosis, spongiosis, superficial perivascular lymphocytic infiltrate, basal melanin hyperpigmentation, and superficial dermal melanophages. We present a study on 2 biopsies from the arm and the thigh in a 77-year-old woman with a long clinical history of Addison disease as well as senile purpura and alopecia of female pattern. The patient presented diffuse hyperpigmentation of the skin, more pronounced on her face, and left upper forehead. The skin biopsies showed no remarkable dermal inflammatory infiltrate with melanocytic hyperpigmentation of the basal layer of the epidermis as well as a mild amount of melanophages in the papillary dermis. In addition, we found lipofuscin in the luminal pole of the secretory epithelium of the eccrine glands. In the perieccrine areas, there was Perls-positive pigment in the cytoplasm of macrophages most likely related to the senile purpura. An immunohistochemical study with Melan-A showed a melanocyte/keratinocyte ratio of 1:20 (5%) in the arm and of less than 1:50 (only 2 melanocytes in the whole section;

http://ift.tt/2zYsDaS

Ulcerating Tumor of the Scalp: Challenge

imageNo abstract available

http://ift.tt/2zYwSTZ

Magnetofection is superior to other chemical transfection methods in a microglial cell line

elsevier-non-solus.png

Publication date: 1 January 2018
Source:Journal of Neuroscience Methods, Volume 293
Author(s): Silke Smolders, Sofie Kessels, Sophie Marie-Thérèse Smolders, Florent Poulhes, Olivier Zelphati, Cedric Sapet, Bert Brône
BackgroundMicroglia, the resident phagocytic cells of the brain, have recently been the subject of intense investigation given their role in pathology and normal brain physiology. In general, phagocytic cells are hard to transfect with plasmid DNA. The BV2 cell line is a murine cell line of microglial origin which is often used to study this cell type in vitro. Unfortunately, this microglial cell line is, like other phagocytic cells, resistant to transfection.New methodMagnetofection is a well-established transfection method that combines DNA with magnetic particles which, under the influence of a magnetic field, ensures a high concentration of particles in proximity of cultured cells. Only recently, Glial-Mag was specifically developed for efficient transfection of microglia and microglial cell lines.ResultsMagnetofection with Glial-Mag yielded a transfection efficiency of 34.95% in BV2 cells, 24h after transfection with an eGFP-expressing plasmid. Efficient gene delivery caused a modest and short-lived cell activation (as measured by IL6 secretion) that ceased by 24h after transfection.Comparison with existing methodsHere we show that Glial-Mag magnetofection of BV2 cells yielded a significantly higher transfection efficiency (34.95%) compared to other chemical transfection methods including calcium-phoshate precipication (0.34%), X-tremeGENE (3.30%) and Lipofectamine 2000 (12.51%).ConclusionTransfection of BV2 cells using Glial-Mag magnetofection is superior compared to other chemical transfection methods and could be considered as the method of choice to chemically transfect microglial cell lines.



http://ift.tt/2hTB2Fx

Online detection of amplitude modulation of motor-related EEG desynchronization using a lock-in amplifier: Comparison with a fast Fourier transform, a continuous wavelet transform, and an autoregressive algorithm

1-s2.0-S0165027017X00162-cov150h.gif

Publication date: 1 January 2018
Source:Journal of Neuroscience Methods, Volume 293
Author(s): Kenji Kato, Kensho Takahashi, Nobuaki Mizuguchi, Junichi Ushiba
BackgroundNeurofeedback of event-related desynchronization (ERD) in electroencephalograms (EEG) of the sensorimotor cortex (SM1) using a brain–computer interface (BCI) paradigm is a powerful tool to promote motor recovery from post-stroke hemiplegia. However, the feedback delay attenuates the degree of motor learning and neural plasticity.New methodThe present study aimed to shorten the delay time to estimate amplitude modulation of the motor-imagery-related alpha and beta SM1-ERD using a lock-in amplifier (LIA) algorithm. The delay time was evaluated by calculating the value of the maximal correlation coefficient (MCC) between the time-series trace of ERDs extracted by the online LIA algorithm and those identified by an offline algorithm with the Hilbert transform (HT).ResultsThe MCC and delay values used to estimate the ERDs calculated by the LIA were 0.89±0.032 and 200±9.49ms, respectively.Comparison with Existing Method(s)The delay time and MCC values were significantly improved compared with those calculated by the conventional fast Fourier transformation (FFT), continuous Wavelet transformation (CWT), and autoregressive (AR) algorithms. Moreover, the coefficients of variance of the delay time and MCC values across trials were significantly lower in the LIA compared with the FFT, CWT, and AR algorithms.ConclusionsThese results indicate that the LIA improved the detection delay, accuracy, and stability for estimating amplitude modulation of motor-related SM1-ERD. This would be beneficial for BCI paradigms to facilitate neurorehabilitation in patients with motor deficits.



http://ift.tt/2jLGwme

Water wave energy harvesting and self-powered liquid-surface fluctuation sensing based on bionic-jellyfish triboelectric nanogenerator

Publication date: Available online 22 November 2017
Source:Materials Today
Author(s): Bao Dong Chen, Wei Tang, Chuan He, Chao Ran Deng, Lei Jing Yang, Lai Pan Zhu, Jian Chen, Jia Jia Shao, Long Liu, Zhong Lin Wang
Due to the natural working mechanism of triboelectric nanogenerators (TENGs), potential energy stored by elastic materials may not be effectively converted into electric power, post mechanical triggering. Here, we report a practical bionic-jellyfish triboelectric nanogenerator (bjTENG) with polymeric thin film as the triboelectric material, which is shape-adaptive, with a hermetic package and a unique elastic resilience structure, similar to the behavior of a jellyfish. The charge separation in the elastic resilience of this bionic-structure is based on the liquid pressure-induced contact-separation of the triboelectric layers. On the basis of the conjunction of the triboelectrification and the electrostatic induction, a sustainable and enhanced output performance of 143 V, 11.8 mA/m2 and 22.1 μC/m2 under a low frequency of 0.75 Hz and at a water depth of 60 cm is produced, which can be used to supply power for dozens of green LEDs or a temperature sensor directly. More significantly, bjTENG is believed to be a priority technology which is attributable to its highly sensitivity, portability, and suitability for continuous detection of water level and fluctuation. Furthermore, a wireless self-powered fluctuation sensor early-warning system, which provides exact and wireless monitoring of fluctuation of a liquid surface, is also successfully developed.

Graphical abstract

image


http://ift.tt/2BeGDej

Recent advances in gas storage and separation using metal–organic frameworks

Publication date: Available online 22 November 2017
Source:Materials Today
Author(s): Hao Li, Kecheng Wang, Yujia Sun, Christina T. Lollar, Jialuo Li, Hong-Cai Zhou
Gas storage and separation are closely associated with the alleviation of greenhouse effect, the widespread use of clean energy, the control of toxic gases, and various other aspects in human society. In this review, we highlight the recent advances in gas storage and separation using metal-organic frameworks (MOFs). In addition to summarizing the gas uptakes of some benchmark MOFs, we emphasize on the desired chemical properties of MOFs for different gas storage/separation scenarios. Greenhouse gases (CO2), energy-related gases (H2 and CH4), and toxic gases (CO and NH3) are covered in the review.

Graphical abstract

image


http://ift.tt/2BbYQtb

A comprehensive analysis of resting state fMRI measures to classify individual patients with Alzheimer's disease

elsevier-non-solus.png

Publication date: 15 February 2018
Source:NeuroImage, Volume 167
Author(s): Frank de Vos, Marisa Koini, Tijn M. Schouten, Stephan Seiler, Jeroen van der Grond, Anita Lechner, Reinhold Schmidt, Mark de Rooij, Serge A.R.B. Rombouts
Alzheimer's disease (AD) patients show altered patterns of functional connectivity (FC) on resting state functional magnetic resonance imaging (RSfMRI) scans. It is yet unclear which RSfMRI measures are most informative for the individual classification of AD patients. We investigated this using RSfMRI scans from 77 AD patients (MMSE = 20.4 ± 4.5) and 173 controls (MMSE = 27.5 ± 1.8). We calculated i) FC matrices between resting state components as obtained with independent component analysis (ICA), ii) the dynamics of these FC matrices using a sliding window approach, iii) the graph properties (e.g., connection degree, and clustering coefficient) of the FC matrices, and iv) we distinguished five FC states and administered how long each subject resided in each of these five states. Furthermore, for each voxel we calculated v) FC with 10 resting state networks using dual regression, vi) FC with the hippocampus, vii) eigenvector centrality, and viii) the amplitude of low frequency fluctuations (ALFF). These eight measures were used separately as predictors in an elastic net logistic regression, and combined in a group lasso logistic regression model. We calculated the area under the receiver operating characteristic curve plots (AUC) to determine classification performance. The AUC values ranged between 0.51 and 0.84 and the highest were found for the FC matrices (0.82), FC dynamics (0.84) and ALFF (0.82). The combination of all measures resulted in an AUC of 0.85. We show that it is possible to obtain moderate to good AD classification using RSfMRI scans. FC matrices, FC dynamics and ALFF are most discriminative and the combination of all the resting state measures improves classification accuracy slightly.



http://ift.tt/2ztIG13

Truncated RAP-MUSIC (TRAP-MUSIC) for MEG and EEG source localization

Publication date: 15 February 2018
Source:NeuroImage, Volume 167
Author(s): Niko Mäkelä, Matti Stenroos, Jukka Sarvas, Risto J. Ilmoniemi
Electrically active brain regions can be located applying MUltiple SIgnal Classification (MUSIC) on magneto- or electroencephalographic (MEG; EEG) data. We introduce a new MUSIC method, called truncated recursively-applied-and-projected MUSIC (TRAP-MUSIC). It corrects a hidden deficiency of the conventional RAP-MUSIC algorithm, which prevents estimation of the true number of brain-signal sources accurately. The correction is done by applying a sequential dimension reduction to the signal-subspace projection. We show that TRAP-MUSIC significantly improves the performance of MUSIC-type localization; in particular, it successfully and robustly locates active brain regions and estimates their number. We compare TRAP-MUSIC and RAP-MUSIC in simulations with varying key parameters, e.g., signal-to-noise ratio, correlation between source time-courses, and initial estimate for the dimension of the signal space. In addition, we validate TRAP-MUSIC with measured MEG data. We suggest that with the proposed TRAP-MUSIC method, MUSIC-type localization could become more reliable and suitable for various online and offline MEG and EEG applications.

Graphical abstract

image


http://ift.tt/2mSw9OF

Population receptive field (pRF) measurements of chromatic responses in human visual cortex using fMRI

elsevier-non-solus.png

Publication date: 15 February 2018
Source:NeuroImage, Volume 167
Author(s): Lauren E. Welbourne, Antony B. Morland, Alex R. Wade
The spatial sensitivity of the human visual system depends on stimulus color: achromatic gratings can be resolved at relatively high spatial frequencies while sensitivity to isoluminant color contrast tends to be more low-pass. Models of early spatial vision often assume that the receptive field size of pattern-sensitive neurons is correlated with their spatial frequency sensitivity - larger receptive fields are typically associated with lower optimal spatial frequency. A strong prediction of this model is that neurons coding isoluminant chromatic patterns should have, on average, a larger receptive field size than neurons sensitive to achromatic patterns. Here, we test this assumption using functional magnetic resonance imaging (fMRI). We show that while spatial frequency sensitivity depends on chromaticity in the manner predicted by behavioral measurements, population receptive field (pRF) size measurements show no such dependency. At any given eccentricity, the mean pRF size for neuronal populations driven by luminance, opponent red/green and S-cone isolating contrast, are identical. Changes in pRF size (for example, an increase with eccentricity and visual area hierarchy) are also identical across the three chromatic conditions. These results suggest that fMRI measurements of receptive field size and spatial resolution can be decoupled under some circumstances - potentially reflecting a fundamental dissociation between these parameters at the level of neuronal populations.



http://ift.tt/2mUaJRl

A common periodic representation of interaural time differences in mammalian cortex

elsevier-non-solus.png

Publication date: 15 February 2018
Source:NeuroImage, Volume 167
Author(s): Nelli H. Salminen, Simon J. Jones, Gestur B. Christianson, Torsten Marquardt, David McAlpine
Binaural hearing, the ability to detect small differences in the timing and level of sounds at the two ears, underpins the ability to localize sound sources along the horizontal plane, and is important for decoding complex spatial listening environments into separate objects – a critical factor in 'cocktail-party listening'. For human listeners, the most important spatial cue is the interaural time difference (ITD). Despite many decades of neurophysiological investigations of ITD sensitivity in small mammals, and computational models aimed at accounting for human perception, a lack of concordance between these studies has hampered our understanding of how the human brain represents and processes ITDs. Further, neural coding of spatial cues might depend on factors such as head-size or hearing range, which differ considerably between humans and commonly used experimental animals. Here, using magnetoencephalography (MEG) in human listeners, and electro-corticography (ECoG) recordings in guinea pig—a small mammal representative of a range of animals in which ITD coding has been assessed at the level of single-neuron recordings—we tested whether processing of ITDs in human auditory cortex accords with a frequency-dependent periodic code of ITD reported in small mammals, or whether alternative or additional processing stages implemented in psychoacoustic models of human binaural hearing must be assumed. Our data were well accounted for by a model consisting of periodically tuned ITD-detectors, and were highly consistent across the two species. The results suggest that the representation of ITD in human auditory cortex is similar to that found in other mammalian species, a representation in which neural responses to ITD are determined by phase differences relative to sound frequency rather than, for instance, the range of ITDs permitted by head size or the absolute magnitude or direction of ITD.



http://ift.tt/2ztQuzX

Effects of soil properties and aging process on the acute toxicity of cadmium to earthworm Eisenia fetida

Abstract

This study was undertaken to investigate the effects of soil properties and aging process on the acute toxicity of cadmium (Cd) to Eisenia fetida (E. fetida) in 18 Cd-spiked soils. Results showed that the Cd toxicity to E. fetida differed in the 18 soils with different characteristics, and median lethal concentration (LC50) values varied from 440.7 to 1520.4 mg/kg in freshly spiked soils. Soil pH and organic matter (OM) content were the two major factors associated with Cd toxicity. The increase in LC50 values and decreases in both exchangeable Cd in soils and tissue Cd concentrations in earthworm whole body indicated that aging (180 and 360 days) could reduce the acute toxicity and bioavailability of Cd to E. fetida. Cadmium concentrations in E. fetida were positively correlated with exchangeable Cd content in soils, and soil pH and OM were the key factors controlling the distribution and transformation of the exchangeable Cd. The results will provide useful reference information for the risk assessment of Cd in the terrestrial environment.



http://ift.tt/2hV1G10

Assessment of oral and lung bioaccessibility of Cd and Pb from smelter-impacted dust

Abstract

Soil and dust contamination by metals engenders significant environmental and health problems in northern France where a lead smelter was in activity for more than a century. This study aims to examine the long-term effects of the smelter, 10 years after its closedown, on the presence of metal in sidewalk dust for a better assessment of the local population's exposure to Cd and Pb. The investigation included: (i) the metal distribution in different dust particle sizes and (ii) the assessment of metal bioaccessibility via ingestion and inhalation of dust. Seventy-two sidewalk dust samples were collected using a dust-sampling vacuum. The samples were sieved to collect different particle sizes from 0.3 to 1000 μm. The unified bioaccessibility method (UBM) was employed to evaluate the oral bioaccessibility of metals in the different particle sizes. The pulmonary bioaccessible fraction of Cd and Pb via the finest particles was extracted with lung-simulating solution (artificial lysosomal fluid). Ten years after the smelter closedown, (i) a strong relationship was observed between the concentrations of metals in dust and the distance to the former smelter, whatever the particle size; (ii) both total and oral bioaccessible concentrations of metals were high in the finest fraction (0.3–5 μm) and decreased when the particle size increased; (iii) a higher oral bioaccessibility of Cd and Pb was measured in the gastric phase (on average 43% for both metals for all particle sizes) and compared to the gastrointestinal phase (on average 16% for both metals for all particle sizes); and (iv) metal bioaccessibility via inhalation of dust was relatively high (on average 74 and 69%, for Cd and Pb, respectively). The results of the present study suggest that this environmental compartment may be a sensitive and effective indicator of anthropogenic metal contamination and the human exposure in urban areas.



http://ift.tt/2jMWQDs

Αναζήτηση αυτού του ιστολογίου