Recommendation to test limonene hydroperoxides 0·3% and linalool hydroperoxides 1·0% in the British baseline patch test series.

BACKGROUND: There is a significant rate of sensitization worldwide to the oxidized fragrance terpenes limonene and linalool. Patch testing to oxidized terpenes is not routinely carried out; the ideal patch test concentration is unknown. OBJECTIVES: To determine the best test concentrations for limonene and linalool hydroperoxides, added to the British baseline patch test series, to optimize detection of true allergy and to minimize irritant reactions. METHODS: During 2013-2014, 4563 consecutive patients in 12 U.K. centres were tested to hydroperoxides of limonene in petrolatum (pet.) 0·3%, 0·2% and 0·1%, and hydroperoxides of linalool 1·0%, 0·5% and 0·25% pet. Irritant reactions were recorded separately from doubtful reactions. Concomitant reactions to other fragrance markers and clinical relevance were documented. RESULTS: Limonene hydroperoxide 0·3% gave positive reactions in 241 (5·3%) patients, irritant reactions in 93 (2·0%) and doubtful reactions in 110 (2·4%). Linalool hydroperoxide 1·0% gave positive reactions in 352 (7·7%), irritant reactions in 178 (3·9%) and doubtful reactions in 132 (2·9%). A total of 119 patients with crescendo reactions to 0·3% limonene would have been missed if only tested with 0·1% and 131 patients with crescendo reactions to 1·0% linalool would have been missed if only tested with 0·25%. In almost two-thirds of patients with positive patch tests to limonene and linalool the reaction was clinically relevant. The majority of patients did not react to any fragrance marker in the baseline series. CONCLUSIONS: We recommend that limonene hydroperoxides be tested at 0·3% and linalool hydroperoxides at 1·0% in the British baseline patch test series.

Does dermatoneuro syndrome have a viral aetiology?

Scleromyxoedema is a rare disease characterized by a generalized papular and sclerodermoid cutaneous eruption. It is associated with fibroblast proliferation and mucin deposition in the dermis. Most patients have a monoclonal gammopathy, defined by the presence of IgG. Treatment of scleromyxoedema is challenging, but there is mounting evidence to support the use of intravenous immunoglobulin (IVIg). Individual reports of systemic complications have been described. Dermatoneuro syndrome (DNS) is a rare but sometimes fatal manifestation, which consists of a triad of fever, coma and seizures preceded by a flu-like illness. We describe a patient with scleromyxoedema who developed DNS. Our case highlights interesting findings suggesting that DNS may have a viral aetiology. In addition, this case demonstrates a favourable response of the cutaneous features of scleromyxoedema to IVIg.

Band-gap engineering by molecular mechanical strain-induced giant tuning of the luminescence in colloidal amorphous porous silicon nanostructures.

Nano-silicon is a nanostructured material in which quantum or spatial confinement is the origin of the material's luminescence. When nano-silicon is broken into colloidal crystalline nanoparticles, its luminescence can be tuned across the visible spectrum only when the sizes of the nanoparticles, which are obtained via painstaking filtration methods that are difficult to scale up because of low yield, vary. Bright and tunable colloidal amorphous porous silicon nanostructures have not yet been reported. In this letter, we report on a 100 nm modulation in the emission of freestanding colloidal amorphous porous silicon nanostructures via band-gap engineering. The mechanism responsible for this tunable modulation, which is independent of the size of the individual particles and their distribution, is the distortion of the molecular orbitals by a strained silicon-silicon bond angle. This mechanism is also responsible for the amorphous-to-crystalline transformation of silicon.

A continuum description of the buckling of a line of spheres in a transverse harmonic confining potential.

A line of contacting hard spheres, placed in a transverse confining potential, buckles under compression or when tilted away from the horizontal, once a critical tilt angle is exceeded. This interesting nonlinear problem is enriched by the combined application of both compression and tilt. In a continuous formulation, the profile of transverse sphere displacement is well described by numerical solutions of a second-order differential equation (provided that buckling is not of large amplitude). Here we provide a detailed discussion of these solutions, which are approximated by analytic expressions in terms of Jacobi, Whittaker and Airy functions. The analysis in terms of Whittaker functions yields an exact result for the critical tilt for buckling without compression.

Contact dermatitis to ophthalmic solutions.

Periorbital and eyelid dermatitis is a recalcitrant and often distressing condition. Allergic contact dermatitis to ophthalmic solutions is an important cause of periorbital and eyelid dermatitis. In this review article, we discuss the allergens involved, the difficulties in patch testing, and the recommended concentrations and vehicles for patch testing.

Pertussis resurgence among vaccinated children in Khairpur, Sindh, Pakistan.

OBJECTIVES: To investigate the aetiology of persistent cough among vaccinated children as suspected cases of pertussis in Khairpur District, Sindh, Pakistan. Pertussis or whooping cough, caused by Bordetella pertussis, is re-appearing in many countries despite vaccination coverage. In Khairpur, persistent cough and symptoms similar to pertussis among vaccinated children are common but the aetiology has not been investigated previously. STUDY DESIGN: B. pertussis was isolated from cough samples of suspected pertussis patients (n = 700) using the cough plate method with charcoal agar. METHODS: Isolation and confirmation of the clinical isolates of B. pertussis was performed by culture on Bordet-Gengou medium, biochemical tests and polymerase chain reaction. RESULTS: In total, 22 strains of B. pertussis were isolated from clinical cough samples. CONCLUSION: To the authors' knowledge, this is the first report of the presence of pertussis in vaccinated children in Khairpur. There is a need for continuous monitoring of pertussis after immunization programmes in order to assess the efficacy of pertussis vaccination.

Phyllotactic description of hard sphere packing in cylindrical channels.

We develop a simple analytical theory that relates dense sphere packings in a cylinder to corresponding disk packings on its surface. It applies for ratios R=D/d (where d and D are the diameters of the hard spheres and the bounding cylinder, respectively) up to R=1+1/sin(π/5). Within this range the densest packings are such that all spheres are in contact with the cylindrical boundary. The detailed results elucidate extensive numerical simulations by ourselves and others by identifying the nature of various competing phases.

Simultaneous use of erythropoietin and prior bleeding enhances the sensitivity of the peripheral blood micronucleus assay.

Adult rats are generally not considered as a suitable model for the peripheral blood micronucleus (PBMN) assay in regulatory consideration, owing to the splenic removal of the micronucleated cells from circulation. Although prior bleeding (PrB) increases the sensitivity of the PBMN assay in young rats, the volume of bleeding and the associated stress caused are major concerns for its possible use in genotoxicity studies. The present study was aimed to overcome these limitations in using pre-bled young rats in genotoxicity studies. The bleeding volume was reduced by the simultaneous use of erythropoietin (EPO) to increase the sensitivity of PBMN assay. Young Sprague-Dawley (SD, 26 days) rats were used in the study. The kinetics of RETs-to-ERTs ratio was determined in response to EPO (10-3000 IU/kg) or PrB (0.1-1.0 ml) at different time points (0, 6, 12, 24, 36, 48, 72 and 96 h). Injection of EPO (30 IU/kg) and PrB (0.5 ml) led to a significant increase in the MN frequency in the PBMN assay in response to cyclophosphamide and zidovudine. The effect of EPO treatment and/or PrB on cell viability and proliferation in the bone marrow (BM) was examined. The results of the present study clearly demonstrate that the simultaneous use of both EPO and PrB enhances the sensitivity of the PBMN assay in young rats due to increased cellular proliferation in the BM. This may provide a useful experimental model for the evaluation of marginally active genotoxicants.

Micronucleus and comet assay in the peripheral blood of juvenile rat: establishment of assay feasibility, time of sampling and the induction of DNA damage.

Micronucleus (MN) and comet assay can successfully detect the genetic damage in two different cell population of peripheral blood i.e. erythrocytes and lymphocytes. The present study was aimed to investigate the kinetics of MN formation as well as to identify the time of maximum MN induction in the peripheral blood erythrocytes in juvenile rats and thereafter to examine its relationship with the observed DNA damage in the lymphocytes as determined by comet assay. The rat peripheral blood micronucleus (PBMN) assay is generally not preferred owing to the selective elimination of micronucleated cells from the circulation by spleen. However, inefficient splenic removal of micronucleated cells in the juvenile Sprague-Dawley (SD, 26 days) rats conferred advantage to be a suitable model for PBMN assay. The kinetics of MN formation and DNA damage in the peripheral blood were determined with cyclophosphamide (50mg/kg), chlorambucil (30mg/kg), methotrexate (20mg/kg), cisplatin (5mg/kg) and paclitaxel (0.5 and 1mg/kg). All the tested chemicals with different mechanisms of action have induced time-dependant changes in the MN frequency in the peripheral blood erythrocytes. Comet assay in the peripheral blood lymphocytes also revealed similar pattern of rise and fall in the DNA damage. MN frequency and the different comet assay parameters exhibited significant positive correlation with all the tested chemicals and in both of the assays the peak was observed in between 36 and 48h post-treatment. Results of the present study clearly demonstrates that MN frequency in the peripheral blood erythrocytes exhibits positive correlation with the DNA damage in the peripheral blood lymphocytes as evident from different comet assay parameters. Further, the study highlights the detection of DNA damage in two different cell population and establishes the complementary nature of these two bioassays for the genotoxicity testing by combining a conventional technique to the smarter one.

Homogeneous and heterogeneous populations of active rods in two-dimensional channels.

Active swarms, consisting of individual agents which consume energy to move or produce work, are known to generate a diverse range of collective behaviors. Many examples of active swarms are biological in nature (e.g., fish shoals and bird flocks) and have been modeled extensively by numerical simulations. Such simulations of swarms usually assume that the swarm is homogeneous; that is, every agent has exactly the same dynamical properties. However, many biological swarms are highly heterogeneous, such as multispecies communities of micro-organisms in soil, and individual species may have a wide range of different physical properties. Here we explore heterogeneity by developing a simple model for the dynamics of a swarm of motile heterogeneous rodlike bacteria in the absence of hydrodynamic effects. Using molecular dynamics simulations of active rods confined within a two-dimensional rectangular channel, we first explore the case of homogeneous swarms and show that the key parameter governing both dynamics is ratio of the motility force to the steric force. Next we explore heterogeneous or mixed swarms in which the constituent self-propelled rods have a range of motilities and steric interactions. Our results show that the confining boundaries play a strong role in driving the segregation of mixed populations.

Theory of rotational columnar structures of soft spheres.

There is a growing interest in cylindrical structures of hard and soft particles. A promising new method to assemble such structures has recently been introduced by Lee et al. [Lee, Gizynski, and Grzybowski, Adv. Mater. 29, 1704274 (2017)ADVMEW0935-964810.1002/adma.201704274]. They used rapid rotations around a central axis to drive spheres of lower density than the surrounding fluid towards the axis. This resulted in different structures as the number of spheres is varied. Here, we present comprehensive analytic energy calculations for such self-assembled structures, based on a generic soft sphere model, from which we obtain a phase diagram. It displays interesting features, including peritectoid points. These analytic calculations are complemented by preliminary numerical simulations for finite sample sizes with soft spheres. A similar analytic approach could be used to study packings of spheres inside cylinders of fixed dimensions, but with a variation in the number of spheres.

Laparoscopic-assisted transversus abdominis plane block as an effective analgesic in total extraperitoneal inguinal hernia repair: a double-blind, randomized controlled trial.

PURPOSE: Laparoscopic inguinal hernia repair has facilitated early mobilization. Management of post-operative pain is paramount in these day case procedures. The aim of this study was to compare laparoscopic-assisted transversus abdominis plane (TAP) block with periportal local anaesthetic infiltration in managing post-operative pain. METHODS: A double-blind, randomized controlled trial was conducted with patients undergoing elective laparoscopic inguinal hernia repair (January 2016-October 2017). The intervention group received laparoscopic-assisted TAP block with 30 ml 0.25% Bupivacaine. The control group received 15ml of 0.5% Bupivacaine at the periportal sites. Primary outcome measure was assessment of post-operative pain scores using numerical rating on visual analogue scale (VAS) at rest and on coughing at 3 h. Efficacy of TAP block was assessed as reduction in mean pain scores in the order of 2 points using the VAS. RESULTS: 60 (57 males and 3 females) were enrolled; 30 patients were randomized to each group. Patient demographics, anaesthetic and surgical times were similar in both groups. Mean pain scores were significantly reduced in the intervention group at 3 (3.1 vs 1.1 p < 0.001) and 6 h (4.1 vs 1.7 p < 0.001) at rest and on coughing at 3 (4.8 vs 2.1 p < 0.001) and 6 h (5.4 vs 3.0 p < 0.001). Patient satisfaction was higher (8.0 vs 6.8 p < 0.001) and rescue analgesic requirements (169.4vs 71.3 p < 0.001) lower in the intervention group. CONCLUSIONS: This analysis has demonstrated the therapeutic benefit of laparoscopic-assisted TAP block in initial post-operative pain management for patients undergoing elective laparoscopic inguinal hernia repair.

Correction to: Laparoscopic-assisted transversus abdominis plane block as an effective analgesic in total extraperitoneal inguinal hernia repair: a double-blind, randomized controlled trial.

In the original publication, one of the co-author 'M. Riaz' details were missed to include in the author group. The complete author group should read as A. Mughal, A. Khan, J. Rehman, H. Naseem, M. Riaz, R. Waldron, M. Duggan, W. Khan, K. Barry, I. Z. Khan.