Ungual Scabies: A Case Report and Review of Literature

Introduction

Nail unit infestation by scabies mites (ungual scabies) is uncommon. It usually presents with distal subungual lesions, leading to recurrent and persistent disease by acting as a reservoir of infection. Periungual involvement in scabies with nail loss is rare and may lead to severe nail damage.

Case Presentation

We report a 14-year-old boy on chemotherapy for acute lymphocytic leukemia (ALL) who presented with extensive scaling and crusted plaques of scabies. Nail unit revealed periungual crusted plaques with paronychia and onychomadesis involving five digits. It was associated with partial to complete nail loss. Dermoscopy of periungual crusted plaques showed greyish-white scales with brown dots and globules. A sinuous burrow with a brown-triangular structure was visualized in the web space. KOH mount from skin scrapings showed the scabies mites. Treatment of scabies led to a marked improvement.

Conclusion

Though ungual scabies is generally a benign disease, proximal periungual involvement with damage to nail matrix is possible, leading to nail loss. We review manifestations of nail unit scabies reported in literature. Treatment options used and outcomes are also analyzed. The importance of nail-directed therapy in preventing relapses of scabies cannot be undermined.

Paclitaxel-Induced Periarticular Thenar Erythema with Onycholysis Syndrome

Introduction

Periarticular thenar erythema with onycholysis (PATEO) syndrome is a rare subtype of hand-foot syndrome seen in patients undergoing taxane-based chemotherapy. It presents as erythematous to violaceous plaques on the dorsum of hands, feet, and around the Achilles tendon along with nail changes, particularly onycholysis.

Case Presentation

A 39-year-old female on paclitaxel chemotherapy for stage IIIA (T3N2aM0) invasive ductal breast carcinoma, presented with mildly tender erythematous to violaceous plaques involving the dorsa of bilateral hands and feet, in the periarticular areas of the Achilles tendon, with facial involvement. All fingernails showed shortening, orange-red chromonychia, Beau's lines, onychoschizia, and subungual debris. The toenail involvement was relatively less severe, with distal onycholysis being the predominant finding. The patient showed significant improvement in cutaneous lesions with topical steroid therapy and was advised cold water immersion during subsequent chemotherapy infusions.

Discussion

A shorter interval between cycles and a higher cumulative number of cycles correlate with severity of dermatitis and nail involvement. Rarely, periocular and facial involvement can occur concurrently with PATEO syndrome. This case is being reported to increase awareness about this entity facilitating early diagnosis and treatment.

Dasatinib-Induced Transverse Melanonychia

Introduction

Transverse melanonychia, characterized by grey to black pigmented bands traversing the nail plate, can occur as a side-effect of certain medications. While no documented reports specifically associate dasatinib, a tyrosine kinase inhibitor used in the treatment of chronic myeloid leukaemia (CML) and acute lymphoblastic leukaemia, with nail changes, we present a case of transverse melanonychia possibly related to dasatinib therapy.

Case Report

A 54-year-old male with CML, receiving dasatinib for 1.5 years, presented with transverse pigmented lines involving all fingernails and toenails. Clinical examination revealed discrete bands of transverse melanonychia in the nails. Onychoscopy of all finger- and toenails revealed multiple longitudinal grey lines within transverse grey bands of homogeneous chromonychia. Based on clinical presentation, onychoscopic features, and temporal association with dasatinib therapy, a provisional diagnosis of dasatinib-induced transverse melanonychia was made.

Discussion

The exact mechanisms underlying melanonychia are not fully understood but may involve nail matrix or toxicity, stimulation of nail-matrix melanocytes, or drug deposition within the nail plate. This case highlights the possibility of dasatinib-induced transverse melanonychia and underscores the importance of monitoring and evaluating nail changes in patients undergoing dasatinib treatment.

THE IMPACT OF SLEEP ON PHYSICAL AND MENTAL HEALTH: IMPORTANCE OF HEALTHY SLEEP HABITS

Sleep is an important part of health, and when you go to sleep, how long you sleep, and how well you sleep all have a big impact on your health. Sleep may be required for regulating the body's metabolism, feelings, function, memory storage, brain recovery, and learning. Because of how important these processes are, sleep should be seen as just as important to health as what you eat and how much you exercise. Adults' sleep generally gets shorter and less restful, their sleep starts later and is more broken up, they have more sleep problems, and their rest-activity rhythms get weaker. In addition to receiving enough sleep (quality), healthy sleep habits also include maintaining a consistent sleep schedule. Ninety male college students with varying sleep schedules were analyzed for their physical and emotional well-being. By using factor analysis to categorize individuals' sleeping patterns across three dimensions regularity, quality, and quantity. We were able to develop sleep-habit measures. Clustering identified four distinct patterns of sleep behavior: good sleep was defined by regular, high-quality sleep despite being of comparatively brief duration; long sleep was predictable, fairly lengthy, but of minimal quality; short sleep was of excellent quality despite being short and irregular; and poor sleep was erratic, low-quality, and relatively long. The excellent sleepers also had reduced diastolic and systolic and a smaller means waist measurement. In addition, the poor sleepers had the lowest average MCS scores of all of the study groups. Poor sleepers also had the lowest mean scores on the Subjective Depression Scale (SDS). Issues involving glucose or lipid absorption were also more common in the short-term and long poor-sleep categories. Without restful sleep and a regular bedtime routine, it is impossible to maintain excellent mental and physical wellness, even if time and sleep are maintained constantly. Therefore, to produce suitable sleep recommendations for enhanced mental and physical health, we evaluated not only the quantity of sleep but also its consistency and high quality.

Contrasting Behaviors of FA and MA Cations in APbBr3

It is known that the organic units in hybrid halide perovskites are free to rotate, but it is not clear if this freedom is of any relevance to the structure-property relationship of these compounds. We have employed quasi-elastic neutron scattering using two different spectrometers, thus providing a wide dynamic range to investigate the cation dynamics in methylammonium lead bromide (MAPbBr₃) and formamidinium lead bromide (FAPbBr₃) over a large temperature range covering all known crystallographic phases of these two compounds. Our results establish a plastic crystal-like phase forming above 30 K within the orthorhombic phase of MAPbBr₃ related to 3-fold rotations of MA units around the C-N axis with an activation energy, E_a, of ∼27 meV, which has no counterpart in the FA compound. MA exhibits an additional 4-fold orientational motion of the whole molecule via rotation of the C-N axis itself with an E_a of ∼68 meV common for the high-temperature tetragonal and cubic phases. In contrast, the FA compound exhibits only an isotropic orientational motion of the whole FA unit with E_a ≈ 106 meV within the orthorhombic phase and a substantially reduced common E_a of ∼62 meV for the high-temperature tetragonal and cubic phases. Our results suggest that the rotational dynamics of the organic units, crystallographic phases, and physical properties of these compounds are intimately connected.

Validation of the Gel & Wax Boluses and Comparison of their Dosimetric Performance with Virtual Bolus

Background

In general, radiotherapy treatment planning is performed using the virtual bolus. It is necessary to investigate physical bolus in comparison to virtual one.

Objectives

In the present study, first, radiological properties of superflab Gel bolus and Paraffin wax bolus was investigated in terms of their relative electron density. Then, dosimetric performance of both the bolus (i.e. Gel and Parafin wax) was compared with Virtual bolus.

Material and Methods

In This experimental study, the radiological property of Wax and Gel boluses was investigated using two methods. In one, the relative electron density of both the Gel and Wax boluses was calculated by measuring their linear attenuation coefficient where in another method relative electron density was calculated by recording their CT No directly from their CT scan. Later CT scan of solid water slab phantom (dimension 30x30x15 cm³), with physical boluses (i.e. Gel and Wax bolus) of appropriate thicknesses required to deliver a dose of 200 cGy at D_max using 4 MV, 6 MV and 15 MV photon beams, was taken. These CT data sets were retrieved to TPS. A plan was done to deliver a dose of 200 cGy at D_max using Single 4 MV, 6 MV and 15 MV photon beams. Dose at depths D_max, 1 cm, 2 cm, 3 cm, 4 cm and 5 cm was recorded. Using this similar method, doses at depths viz D_max, 1 cm, 2 cm, 3 cm, 4 cm and 5 cm was recorded for the Gel and Wax boluses. The differences in dose of gel and wax bolus from virtual bolus were recorded for comparison of their dosimetric performance.

Results

The measured (calculated) relative electron density of wax and Gel bolus was found to be 0.958 (0.926) and 0.923 (0.907), respectively. Variation in dosimetric performance of Gel and Wax with reference to Virtual bolus was studied. However, on average, Gel bolus was more consistent with virtual bolus.

Conclusion

To avoid any dose difference between, delivered (using physical bolus) and planned (using virtual bolus), the physical boluses should be investigated for their dosimetric performance in comparison to virtual bolus. The results obtained and methodology used in this study can be applied in routine radiotherapy practices.

Analytical and computational studies of the nonlinear vibrations of SWCNTs embedded in viscous elastic matrix using KBM method

The forced vibration analysis of single wall carbon nanotubes (SWCNTs) embedded in the viscous elastic matrix subjected to axial parametric excitation has been investigated. The Euler Bernoulli beam model of the non-local continuum theory is used. The resonant and non-resonant solutions are analytically studied using the Krylov Bogoliubov and Mitropolsky method. It has been seen that the amplitude remains constant up to the second order of approximation. The resonant solutions are also found to analyze the possibility of chaos in the neighborhood of resonance. The computational techniques are used, and plots of time series, phase plot, and Poincaré surface of section are also drawn to confirm the chaotic behavior for certain values of parameters of SWCNTs, which may lead the aging process in the SWCNTs after a long time.

Nanoscopic dynamics of bicontinous microemulsions: effect of membrane associated protein

Bicontinous microemulsions (BμE) generally consist of nanodomains formed by surfactant in a mixture of water and oil at nearly equal proportions and are potential candidates for the solubilization and purification of membrane proteins. Here we present the first time report of nanoscopic dynamics of surfactant monolayers within BμEs formed by the anionic surfactant sodium dodecyl sulfate (SDS) measured on the nanosecond to picosecond time scale using quasielastic neutron scattering (QENS). BμEs investigated herein consisted of middle phases isolated from Winsor-III microemulsion systems that were formed by mixing aqueous and oil solutions under optimal conditions. QENS data indicates that surfactants undergo two distinct motions, namely (i) lateral motion along the surface of the oil nanodomains and (ii) localized internal motion. Lateral motion can be described using a continuous diffusion model, from which the lateral diffusion coefficient is obtained. Internal motion of surfactant is described using a model which assumes that a fraction of the surfactants' hydrogens undergoes localized translational diffusion that could be considered confined within a spherical volume. The effect of cytochrome c, an archetypal membrane-associated protein known to strongly partition near the surfactant head groups in BμEs (a trend supported by small-angle X-ray scattering [SAXS] analysis), on the dynamics of BμE has also been investigated. QENS results demonstrated that cytochrome c significantly hindered both the lateral and the internal motions of surfactant. The lateral motion was more strongly affected: a reduction of the lateral diffusion coefficient by 33% was measured. This change is mainly attributable to the strong association of cytochrome c with oppositely charged SDS. In contrast, analysis of SAXS data suggested that thermal fluctuations (for a longer length and slower time scale compared to QENS) were increased upon incorporation of cytochrome c. This study demonstrates the utility of QENS for evaluating dynamics of BμEs in nanoscopic region, and that proteins directly affect the microscopic dynamics, which is of relevance for evaluating release kinetics of encapsulated drugs from BμE delivery systems and the use of BμEs as biomembrane mimetic systems for investigating membrane protein-biomembrane interactions.

SHORT TIME AND STRUCTURAL DYNAMICS IN POLYPROPYLENE GLYCOL NANOCOMPOSITE

The dynamics of polypropylene glycol, both neat and attached to silica nanoparticles, were investigated using elastic neutron backscattering and dielectric spectroscopy. The mean square displacement measured by the former is suppressed by the particles at temperatures corresponding to a dielectric secondary relaxation (that involves only a portion of the repeat unit) and the segmental relaxation (glass transition). Despite the suppression of the displacements, the motions are faster in the nanocomposite, primarily due to poorer packing (lower density) at the particle interface. At very low temperatures we discovered a new dynamic process in the polymer. Reflecting its very local nature, this process is unaffected by attachment of the chains to the silica.

Incorporation of aspirin modulates the dynamical and phase behavior of the phospholipid membrane

Effect of aspirin on the microscopic dynamics of a membrane has been investigated using quasielastic neutron scattering and neutron spin echo techniques.

Dynamical and Phase Behavior of a Phospholipid Membrane Altered by an Antimicrobial Peptide at Low Concentration

The mechanism of action of antimicrobial peptides is traditionally attributed to the formation of pores in the lipid cell membranes of pathogens, which requires a substantial peptide to lipid ratio. However, using incoherent neutron scattering, we show that even at a concentration too low for pore formation, an archetypal antimicrobial peptide, melittin, disrupts the regular phase behavior of the microscopic dynamics in a phospholipid membrane, dimyristoylphosphatidylcholine (DMPC). At the same time, another antimicrobial peptide, alamethicin, does not exert a similar effect on the DMPC microscopic dynamics. The melittin-altered lateral motion of DMPC at physiological temperature no longer resembles the fluid-phase behavior characteristic of functional membranes of the living cells. The disruptive effect demonstrated by melittin even at low concentrations reveals a new mechanism of antimicrobial action relevant in more realistic scenarios, when peptide concentration is not as high as would be required for pore formation, which may facilitate treatment with antimicrobial peptides.

A study on reaction kinetics and development of silicide coatings on Nb–1Zr–0.1C alloy by molten salt technique

In this study a molten salt technique has been used to produce silicide coating on Nb–1Zr–0.1C alloy using a NaCl–KCl–NaF–Na₂SiF₆–Si melt.

Low-temperature water dynamics in an aqueous methanol solution

An aqueous methanol solution (x(MeOH) = 0.30) has been studied by quasielastic neutron scattering. The single-particle water dynamics were effectively isolated by employing deuterated methanol. A smooth dynamic transition to a sub-Arrhenius temperature dependence has been observed in the relaxation times. We associate this behavior with the formation of small crystallites in the system. These findings are compared with molecular dynamics simulations and previous nuclear magnetic resonance measurements. We discuss possible dynamic signatures of structuring in the mixture.

What do we know about self-reported fatigue in systemic lupus erythematosus?

Fatigue is one of the most complex and ill understood symptoms of chronic illness often reported as the number one complaint by patients with systemic lupus erythematosus (SLE). This paper aims to provide a comprehensive review of the literature on fatigue in SLE. A pool of 55 relevant articles was retrieved via electronic searches of six databases including MEDLINE, EMBASE, CINAHL, AMED, PsychINFO and PubMed. Fatigue in the studies reviewed was assessed by a range of self-report instruments, the content of which is varied. The results displayed a consensus on the high prevalence of fatigue in SLE, which is significantly higher when compared with controls. The aetiology of fatigue appears to be multifactorial. Disease activity is not always significantly associated with fatigue, in comparison with other secondary features of SLE and psychological variables. The literature is limited by the cross-sectional nature of most of the studies, which does not permit for any firm conclusion regarding the direction of causal relationships to be made. The high prevalence of fatigue in SLE emphasizes the need for further detailed prospective research to inform the understanding of its aetiology, course and management.

Dynamics of biological macromolecules: not a simple slaving by hydration water

We studied the dynamics of hydrated tRNA using neutron and dielectric spectroscopy techniques. A comparison of our results with earlier data reveals that the dynamics of hydrated tRNA is slower and varies more strongly with temperature than the dynamics of hydrated proteins. At the same time, tRNA appears to have faster dynamics than DNA. We demonstrate that a similar difference appears in the dynamics of hydration water for these biomolecules. The results and analysis contradict the traditional view of slaved dynamics, which assumes that the dynamics of biological macromolecules just follows the dynamics of hydration water. Our results demonstrate that the dynamics of biological macromolecules and their hydration water depends strongly on the chemical and three-dimensional structures of the biomolecules. We conclude that the whole concept of slaving dynamics should be reconsidered, and that the mutual influence of biomolecules and their hydration water must be taken into account.

Glass transition and molecular mobility in polymer thin films

Extensive studies on polymer thin films to date have revealed their interesting but unusual properties such as film thickness dependence of glass transition temperature Tg and thermal expansivity. Recent studies have shown that the lower Tg is not always related to the higher mobility in polymer thin films, which contradicts our current understanding of the glass transition process. In this work, we report the results of inelastic neutron-scattering measurements on polystyrene thin films using two spectrometers with different energy resolutions as well as ellipsometry measurements. The results are interpreted in terms of cooperatively rearranging region and motional slowing down due to the surface effect that explain plausibly the anomalous relationship between the glass transition temperature Tg and the molecular mobility in thin films.

Protein structure mining using a structural alphabet

We present a comprehensive evaluation of a new structure mining method called PB-ALIGN. It is based on the encoding of protein structure as 1D sequence of a combination of 16 short structural motifs or protein blocks (PBs). PBs are short motifs capable of representing most of the local structural features of a protein backbone. Using derived PB substitution matrix and simple dynamic programming algorithm, PB sequences are aligned the same way amino acid sequences to yield structure alignment. PBs are short motifs capable of representing most of the local structural features of a protein backbone. Alignment of these local features as sequence of symbols enables fast detection of structural similarities between two proteins. Ability of the method to characterize and align regions beyond regular secondary structures, for example, N and C caps of helix and loops connecting regular structures, puts it a step ahead of existing methods, which strongly rely on secondary structure elements. PB-ALIGN achieved efficiency of 85% in extracting true fold from a large database of 7259 SCOP domains and was successful in 82% cases to identify true super-family members. On comparison to 13 existing structure comparison/mining methods, PB-ALIGN emerged as the best on general ability test dataset and was at par with methods like YAKUSA and CE on nontrivial test dataset. Furthermore, the proposed method performed well when compared to flexible structure alignment method like FATCAT and outperforms in processing speed (less than 45 s per database scan). This work also establishes a reliable cut-off value for the demarcation of similar folds. It finally shows that global alignment scores of unrelated structures using PBs follow an extreme value distribution. PB-ALIGN is freely available on web server called Protein Block Expert (PBE) at http://bioinformatics.univ-reunion.fr/PBE/.

Positron-annihilation-lifetime response and broadband dielectric relaxation spectroscopy: diethyl phthalate

We report the results of a combined phenomenological analysis of the data from positron-annihilation-lifetime spectroscopy (PALS) and the relaxation data from broadband dielectric spectroscopy (BDS) on diethyl phthalate (DEP). The ortho-positronium (o-Ps) lifetime, tau3, as a function of temperature over a temperature range from 67 K up to 300 K is compared with the spectral features and the relaxation parameters of the BDS spectra decomposed into the primary alpha and the secondary beta processes in the temperature range from 140 K up to 380 K by using the Williams-Watts scheme. Phenomenological model-free analysis of the tau3-T plot provides the three characteristic PALS temperatures, where the two most pronounced ones at TgPALS=185 K and Tb2=245 K=1.32TgPALS are related to the glass-liquid transition and the onset of a quasiplateau region, respectively. In the case of a weaker bend effect at Tb1=210 K=1.14TgPALS, a number of new coincidences with changes in the dielectric beta process have been found. They concern the changes in width parameter of the distribution function for the beta relaxation time and the activation energy of the betaeff process, a crossover from the Arrhenius to the non-Arrhenius type of temperature dependence as well as with the onset of a short-time tail of the beta relaxation time distribution and finally, with changes in the relaxation strength of the alpha and betaeff processes. All these findings indicate a close connection of the o -Ps annihilation parameters and relaxation characteristics of BDS response for the DEP matrix.

Substance P and acetylcholine are co-localized in the pathway mediating mucociliary activity in Rana pipiens

Mucociliary activity is an important clearance mechanism in the respiratory system of air breathing vertebrates. Substance P (SP) and acetylcholine play a key role in the stimulation of the mucociliary transport in the frog palate. In this study, retrograde neuronal tracing was combined with immunocytochemistry for SP and choline acetyl transferase (ChAT) in the trigeminal ganglion and for neurokinin-1 receptor (NK1R) in the palate of Rana pipiens. The cells of origin of the palatine nerve were identified in the trigeminal ganglion using the retrograde tracer Fluorogold (FG). Optimal labeling of FG cells in the trigeminal ganglion was obtained at 96 h of exposure. Immunoflorescent shows that SP and acetylcholine are co-localized in 92% of the cells labeled with FG in the trigeminal ganglion. NK1 receptors were found in the membrane of epithelial and goblet cells of the palate. Ultrastructural study of the palate showed axonal-like endings with vesicles in connection with epithelial and goblet cells. These results further support the concerted action of both neurotransmitters in the regulation of mucociliary activity in the frog palate.

Protein Block Expert (PBE): a web-based protein structure analysis server using a structural alphabet

Encoding protein 3D structures into 1D string using short structural prototypes or structural alphabets opens a new front for structure comparison and analysis. Using the well-documented 16 motifs of Protein Blocks (PBs) as structural alphabet, we have developed a methodology to compare protein structures that are encoded as sequences of PBs by aligning them using dynamic programming which uses a substitution matrix for PBs. This methodology is implemented in the applications available in Protein Block Expert (PBE) server. PBE addresses common issues in the field of protein structure analysis such as comparison of proteins structures and identification of protein structures in structural databanks that resemble a given structure. PBE-T provides facility to transform any PDB file into sequences of PBs. PBE-ALIGNc performs comparison of two protein structures based on the alignment of their corresponding PB sequences. PBE-ALIGNm is a facility for mining SCOP database for similar structures based on the alignment of PBs. Besides, PBE provides an interface to a database (PBE-SAdb) of preprocessed PB sequences from SCOP culled at 95% and of all-against-all pairwise PB alignments at family and superfamily levels. PBE server is freely available at .