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Observation of nanosilicon-based contributions to the interstellar nanodust is problematic because the indirect-bandgap of silicon makes its optical features wide, while carbon’s higher abundancy and ionization potential and the rising slope of extinction curves introduce heavy convolution. Recent macroscopic synthesis and charging of nanosilicon, the coming online of the Webb space telescope with unprecedented spectral resolution, and advances in modeling algorithms, light scattering, and fundamental atomistic computation may open opportunities for effective comparison between laboratory and space observation. Here, we study the transport of charged nanosilicon in electric/magnetic fields. We use high voltage across liquid colloids to charge and propel nanosilicon into external fields and imprint them on metal-coated substrates. We use absorption, luminescence, and light scattering in liquid, flight, and imprinted surfaces to study the field deflection of nanosilicon. We use the Mie/finite-difference time-domain theory to obtain scattering curves of nanosilicon and silica. Nanosilicon-based UV features near the 217.5-nm carbon bump are recorded and calculated using Time-Dependent Density Functional Theory (TDDFT) atomistic theory at 225, 280, and 153 nm resulting from bound–bound, and valence-continuum transitions, respectively. We also show that the constituents of silicates, oxygen and Mg and Fe metal ions, can attach to Si nanoparticles without interrupting luminescence, infrared, or UV signatures, respectively. Because charge defects allow nanosilicon transport over large distances via open B fields of solar holes as well as provide them with narrow “atomic-like” transitions, which are otherwise extended, sightlines with lower carbon and higher resolution afforded by Webb may allow the unmasking of Si-based features.

The classical light interactions of nanosilicon, which is a dielectric material, are exceedingly weak for radius r ≪ λ (wavelength), scaling as r6. It exhibits geometrical anisotropy-based depolarization, which is the basis for the very weak response in isotropic structures (nanosphere). Recently, surface enhanced Raman scattering (SERS) in DNA decorated with ultrasmall Si nanoparticles has been demonstrated, affording an effective alternative to plasmon–metal particles. In this paper, we execute fundamental quantum atomistic computation of 1 nm hydrogenated Si particles, with different surface reconstruction and termination, including Si–H, H–Si–Si–H (dimer molecules), or oxygenated dimer bridges (H–Si–O–Si–H). We obtain the mechanical vibrational modes of the particles. Our results show that by changing the surface configuration one can control the symmetry and normal vibration modes, and enhance the polarizability, polarity, and light interactions (scattering, absorption, and depolarization/memory). The low frequency polarizability (Raman scattering) shifts spatially from the interior to the surface, while the infrared polarity remains on the surface, but its bandwidth narrows spectrally. The results support previous infrared absorption and light scattering and depolarization measurements, as well recent SERS, which enable Si nanoparticles to be an effective alternative to plasmonic metal particles. Molecular surface reconstruction in terms of Si dimers and bridges were suggested as the source of the novel nonlinear and anisotropic luminescence and photonic properties of Si nanoparticles. Such control affords potential for optimizing the design and operation of a wide range of opto-electronic advanced scattering and luminescence devices.

Silicon, a highly symmetric and homogeneous material, does not exhibit fast optical modulation. Recent classical electrodynamics simulations, however, demonstrated transient optical heterogeneity in silicon nanostructures, in which a high-density of excitonic electron–hole pair plasma and charge is created. The phenomenon, however, requires a specific particle size (∼100 nm diameter) and a high-density (1023/cc) plasma. We examine here the quantum aspect of the heterogeneity in 1-nm Si nanoparticles. Due to the small number of atoms, 1 nm nanoparticles are amenable to the Hartree–Fock first principle atomistic quantum theory simulations procedure, while single ionization events are sufficient to provide high charge density (2 × 1021/cc). The simulations show that the charge distribution in singly charged 1-nm particles is nonlinear and heterogeneous, accompanied with structural distortion that produces an electric dipole moment. Electronically, the simulations show that the single charge induces stationary Coulomb states that riddle the bandgap of the neutral particle, with dipole-allowed transitions, effectively inducing partial conducting-like behavior. Optically, when the charge is produced by ionizing UV radiation, the ionized particle survives and exhibits both extended (wide-band) as well as atomic- or ion-like sharp emission, in agreement with infrared polarimetry and spectroscopy observations in the solar coronal holes, as well as under synchrotron irradiation. Not only do ionized Si nanoparticles (charged nanosilicon grains) afford fast optical modulations, but they may also prove pivotal for understanding features of interstellar medium, observed throughout the Milky Way and other galaxies, including spectroscopic and material composition, as well as neutral hydrogen abundancy.

The thermodynamics of nanosystems is interesting, as they constitute the transition between the atomistic and solid states. This is empowered by the development of tools to manipulate individual atoms and perform atomistic simulations and fundamental thermos-science, such as microscopic time-symmetry and macroscopic time-asymmetry, the origin of time’s arrow, and photo-cryo-refrigeration. We examine here the photo-thermo and time dynamics in 1-nm silicon nanoparticles with tetrahedral-molecular core–shell structure prepared ex situ and suspended in solvents or re-constituted in films. We examined the temperature dependence of the quantum efficiency and time-dynamics of the Stokes luminescence and its energy dependence across the band. With temperature, we get flat lifetimes but with delay in the onset in agreement with a model calculation of above barrier emission. Our atomistic time-dependent density functional theory shows that Stokes heating takes place in the molecular-like shell where the lifetime is in the nanosecond regime, whereas anti-Stokes cooling takes place in the tetrahedral core where the lifetime is in the ms regime. Unlike doped glasses, we observed a 2-order of magnitude increase in the quantum efficiency of the Stokes luminescence at 10° K. The increase in the quantum efficiency at low temperature, the high quantum efficiency of stimulated anti-Stokes scattering and its anti-correlation with the luminescence, and the visible transparency/blindness due to quantum confinement are requirements for solid state photo-cooling, which may afford an all-silicon photo-cryo-refrigeration, with potential full integration into the CMOS silicon industry.

A new variety of zinc biofortified wheat (Zincol-2016) was released in Pakistan in 2016. The primary aim of this study was to examine the effects of consuming Zincol-2016 wheat flour on biochemical and functional markers of zinc status in a population with widespread zinc deficiency. An individually-randomised, double-blind, placebo-controlled cross over design was used. Fifty households were recruited to participate in the study, with each household included at least one woman of reproductive age (16–49 years) who was neither pregnant nor breast feeding or currently taking nutritional supplements. All households were provided with control flour for an initial 2-week baseline period, followed by the intervention period where households were randomly allocated in a 1:1 ratio to receive biofortified flour (group A; n = 25) and control flour (group B; n = 25) for 8-weeks, then switched to the alternate flour for 8-weeks. The trial has been registered with the ISRCTN (https://www.isrctn.com), ID ISRCTN83678069. The primary outcome measure was plasma zinc concentration, and the secondary outcome measures were plasma selenium and copper concentrations, plasma copper:zinc ratio and fatty acid desaturase and elongase activity indices. Nutrient intake was assessed using 24-h dietary recall interviews. Mineral concentrations in plasma were measured using inductively coupled plasma mass spectrometry and free fatty acids and sphingolipids by mass spectrometry. Linear Mixed Model regression and General Linear Model with repeated measures were used to analyse the outcomes. Based on an average flour consumption of 224 g/day, Zincol-2016 flour provided an additional daily zinc intake of between 3.0 and 6.0 mg for white and whole grain flour, respectively. No serious adverse events were reported. This resulted in significant, increase in plasma zinc concentration after 4 weeks [mean difference 41.5 μg/L, 95% CI (6.9–76.1), p = 0.02]. This was not present after 8 weeks (p = 0.6). There were no consistent significant effects of the intervention on fatty acid desaturase and elongase activity indices. Regular consumption of Zincol-2016 flour increased the daily zinc intake of women of reproductive age by 30–60%, however this was not associated with a sustained improvement in indices of zinc status.

Surface enhanced Raman scattering (SERS), in which sample molecules are placed in the proximity of conducting nanostructures, subjects the molecules to intense electron oscillation (plasmon) field. The intense field, however, may cause heavy distortion and thermal damage to the molecule as well as non-separable and heavy convolution with the metal electronic structure. We utilized 3-nm red luminescent Si nanoparticles decorating the DNA molecules (drawn electrostatically) to enhance Raman scattering in solution at 532 nm. We demonstrated that the nanoparticles enhance the spectral resolution and intensity of vibrations of DNA by two orders of magnitude and reveal vibrations that are otherwise weak or forbidden. Theoretically, we conducted calculations of Mie scattering and three-dimensional finite-difference time-domain scattering and obtained the wavelength dependence of the near-field distribution from single or dimer Si particles. The simulations show moderate intensity enhancement (25–40-fold) and exciton resonances. Moreover, it shows that the near field is highly confined, extending only to 3–5 Å from the Si particle (atomic scale) compared to several nanometers for metal nanoparticles. The observed SERS-type characteristics are understood in terms of polarization-based light scattering, which is possible by the use of Si of highly reduced size for which the polarizability and exciton processes are strong. However, multilayers contribute to metal SERS, and monolayers/single molecules dominate the Si case. Weaker but highly confined, ultra-short range polarization-based scattering provides an alternative to plasmon and Mie scattering, while providing practical, straightforward interpretation of vibration printing of bio-medical species without compromising the molecular structure.

Being a global concern, the current scenario of food chain contamination is one of the major threats to human health. Unrestrained human population, industrialization, urbanization, and extensive use of agrochemicals are among the major causes of heavy metals (HMs) contamination in the food chain. The present study was intended to quantify some HMs and to evaluate their sources and health risks in different varieties of onion using standard analytical approaches. Overall, nine HMs were quantified in the bulbs and leaves of nine varieties of onion. Ascending order of HMs’ concentration was as follow: Fe > Zn > Mn > Co > Pb > Cu > Cr > Cd > Li (bulbs) and Fe > Mn > Zn > Cu > Cr > Pb > Co > Li > Cd (leaves). Most of the measured levels were found to be relatively higher in the leaves than bulbs. Red Flame (V4), Super Sarhad (V3), Red Orb (V2), White Pearl (V7) and Zeus (V9) varieties showed elevated levels of Cu, Fe, and Zn; Cr and Mn; Co and Pb; Cd and Li, respectively in the bulbs. Likewise, Red Orb (V2) and White Pearl (V7) revealed elevated levels of the metals, while Golden Orb (V6) exhibited relatively lower metal levels. Highly significant positive correlations (≥90% at p ≤ 0.01) were found between Zn-Cu and Zn-Fe (in bulbs) and Cu-Co (in leaves), indicating their common origin. Principle component analysis indicated substantial anthropogenic contamination of the HMs in onion. In addition, hierarchal clustering revealed associations of different varieties based on similarities in the metal levels. The calculated values of health risk index (HRI), target hazard quotient (THQ), hazard index (HI), and target cancer risk (TCR) in the bulbs and leaves of all varieties were within the safe limit for both adults and children. Therefore, human consumption of these onion varieties is considered safe with respect to the HMs. However, currently used remediation approaches should focus on the reduction of health risks associated with HMs contamination in the food crops.

The present study is based on the measurement of selected metals (Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Pb, Sr and Zn) in the fruits of eight medicinal plants (Carrisa opeca, Phyllanthus emblica, Solanum nigrum, Zizyphus nummularia, Zizyphus mauritiana, Physalis minima, Opuntia dillenii and Phoenix dactylifera) and relevant soil samples by atomic absorption spectrometry. Highest average concentrations of Cu (14.4 mg/kg), Cr (19.0 mg/kg), and Zn (125 mg/kg) were found in the fruits of P. minima, C. opeca and Z. nummularia, respectively, while O. dillenii showed the elevated mean levels of Cd (3.49 mg/kg), Sr (61.4 mg/kg), Mg (0.21%), Ca (6.62%) and Mn (44.6 mg/kg). However, highest average levels of Pb (41.7 mg/kg) and Co (38.4 mg/kg) were found in Z. mauritiana. Overall, most of the fruit samples showed higher contributions of Ca and Mg, followed by Fe, Zn, Co and Pb. In the case of soil samples, highest concentration was observed for Ca, followed by Fe, Mg, Mn and Sr, while lowest concentration was shown by Cd. Bioaccumulation factors exhibited significantly higher accumulation of Co (0.813–1.829) and Pb (0.060–2.350) from the soil to the fruits. Principal component analysis revealed significant anthropogenic contributions of Pb, Fe and Co in the fruit samples. Contamination factors and enrichment factors of Cd and Pb in the soil indicated very high contamination and extreme enrichment of these metals. Keywords: Bioaccumulation, Fruit, Medicinal plant, Metal, Enrichment, Health risk

Although fish are often recommended as a component of a healthy diet, the environmental accumulation of heavy metals in many fish species has been of considerable concern for those weighing the nutritional health benefits against adverse toxic outcome of excess intake of toxic metals. This study aimed to determine the concentration of essential and toxic metals in the tissues of Catla catla in Mangla Lake and to assess the possible risk to the consumers. Fifty samples of Catla catla were collected from Mangla Lake, Mirpur, Azad Jammu and Kashmir, Pakistan and analyzed for eighteen metals including essential and trace metals. The measured range concentrations (µg/g, wet weight) in muscle tissues, in decreasing order, were: K (955–1632), Ca (550–2081), Na (449–896), Mg (129–312), Zn (61.2–215), Fe (11.6–26.8), Sr (2.60–9.27), Pb (1.72–7.81), Se (1.55–3.55), Co (0.12–4.08), Mn (1.04–4.33), Ni (0.69–3.06), Cu (0.88–2.78), Cr (0.45–1.88), As (0.67–1.58), Cd (0.28–0.56), Hg (0.17–0.57) and Li (0.12–0.38). The metal concentrations found in this study were comparatively higher than those reported in literature. A majority of the metals exhibited higher accumulation in gills compared with those in scales and muscles. Mean levels of Pb, As, Co, Mn, Cd, Cr and Zn in Catla catla muscle were found to be exceeding the international permissible limits for the safe human consumption. The condition factor (K), as an indicator of fish health status, indicated that Catla catla of Mangla Lake are in good health condition. The metal pollution index (MPI) of gills (27.9), scales (12.5) and muscle (7.57) indicated low contamination. Moreover, human health risk was evaluated using estimated weekly intake (EWI) and daily intake (EDI), target hazard quotient (THQ), hazard index (HI) and target cancer risk (TCR). Estimated weekly and daily intake values for As, Cd, Cr, Hg, Ni and Pb were higher than provisional permissible tolerable weekly intake and permissible tolerable daily intake while THQ for As, Cd, Cr, Hg, Pb, Se and Zn was higher than 1. The THQ for As, Hg and Pb was several folds higher than 1, indicative of lifetime non-carcinogenic health risks to the consumers. The hazard index indicated cumulative risk, which greatly increased with increasing fish consumption. Target cancer risk indicated that the people eating the Catla catla from Mangla Lake were exposed to As, Cd, Cr, Ni and Pb with a significant lifetime carcinogenic risk. In summary, consumption of Catla catla from this lake was found to be associated with an increased lifetime risk to the general health of the consumers.

Introduction Micronutrient deficiencies, commonly referred to as ‘hidden hunger’, affect more than two billion people worldwide, with zinc and iron-deficiency frequently reported. The aim of this study is to examine the impact of consuming zinc biofortified flour (Zincol-2016) on biochemical and functional measures of status in adolescent girls and children living in a low-resource setting in Pakistan.Methods and analysis We are conducting a pragmatic, cluster-randomised, double-blind, controlled trial. A total of 482 households have been recruited from two catchment areas approximately 30–40 km distance from Peshawar. Household inclusion criteria are the presence of both an adolescent girl, aged 10–16 years, and a child aged 1–5 years. The study duration is 12 months, divided into two 6-month phases. During phase 1, all households will be provided with locally procured flour from standard varieties of wheat. During phase 2, clusters will be paired, and randomised to either the control or intervention arm of the study. The intervention arm will be provided with zinc biofortified wheat flour, with a target zinc concentration of 40 mg/kg. The control arm will be provided with locally procured wheat flour from standard varieties with an expected zinc concentration of 20 mg/kg. The primary outcome measure is plasma zinc concentration. Secondary outcomes include anthropometric measurements, biomarkers of iron and zinc status, and the presence and duration of respiratory tract infections and diarrhoea.Ethics and dissemination Ethical approval was granted from the University of Central Lancashire STEMH Ethics Committee (reference number: STEMH 1014) and Khyber Medical University Ethics Committee (DIR/KMU-EB/BZ/000683). The final study methods will be published in peer-reviewed journals, alongside the study outcomes. In addition, findings will be disseminated to the scientific community via conference presentations and abstracts and communicated to the study participants through the village elders at an appropriate community forum.Trial registration number ISRCTN17107812; Pre-results.

Background: Biofortification of wheat with zinc (Zn) through breeding and agronomy can reduce Zn deficiencies and improve human health. “High-Zn” wheat varieties have been released in India and Pakistan, where wheat is consumed widely as a dietary staple. The aim of this study was to quantify the potential contribution of a “high-Zn” wheat variety (Triticum aestivum L. var. Zincol-2016) and Zn fertilizers to improving dietary Zn supply under field conditions in Pakistan.Methods: Grain Zn concentration of Zincol-2016 and local reference varieties were determined at three sites of contrasting soil Zn status: Faisalabad (Punjab Province; diethylenetriamine pentaacetate- (DTPA-)extractable Zn, 1.31 mg kg−1 soil; gross plot size 13.3 m2; n = 4; reference var. Faisalabad-2008), Islamabad (Capital Territory; 0.48 mg kg−1; 4.6 m2; n = 5; reference var. NARC-2011), and Pir Sabak (Khyber Pakhtunkhwa, KPK, Province; 0.12 mg kg−1 soil; 9.1 m2; n = 4; reference vars. Pirsabak-2015, Wadhan-2017). Eight Zn fertilizer treatment levels were tested using a randomized complete block design: control; soil (5 or 10 kg ha−1 ZnSO4.H2O; 33% Zn applied at sowing); foliar (0.79 or 1.58 kg of ZnSO4.H2O ha−1 applied as a 250 L ha−1 drench at crop booting stage); three soil × foliar combinations.Results: At the Faisalabad site, the grain Zn concentration of Zincol-2016 was greater than Faisalabad-2008, with no yield penalty. Zincol-2016 did not have larger grain Zn concentrations than reference varieties used at Islamabad or Pir Sabak sites, which both had a lower soil Zn status than the Faisalabad site. Foliar Zn fertilization increased grain Zn concentration of all varieties at all sites. There were no significant effects of soil Zn fertilizers, or variety·fertilizer interactions, on grain Zn concentration or yield.Conclusions: Environment and management affect the performance of “high-Zn” wheat varieties, and these factors needs to be evaluated at scale to assess the potential nutritional impact of Zn biofortified crops. Designing studies to detect realistic effect sizes for new varieties and crop management strategies is therefore an important consideration. The current study indicated that nine replicate plots would be needed to achieve 80% power to detect a 25% increase in grain Zn concentration.

Redox-type charge exchange between Si nanoparticles and aqueous metal ions mx+ was recently used to synthesize core–shell nanocomposites in which their functionalities have been integrated. The process requires the electron (hole) affinities of the two to be different, with the efficiency of the charge exchange being strongly dependent on their difference. In this paper, we examine the interaction of Fe ions and red luminescent Si nanoparticles where the metal ion has comparable electron affinity to that of the Si nanoparticle. Scanning electron microscopy and fluorescent spectroscopy imaging show the formation of red luminescent core-shell clusters ranging from 100 nm to 500 nm. A permanent magnet is found to pull the structures indicating the formation of a magnetic phase. We use first principle atomistic computations at the unrestricted Hartree–Fock-DFT (density functional theory) level to obtain the charging energies and affinities of various ions of Fe and the Si nanoparticle. The computations indicate that Fe2+ cannot be oxidized to Fe3+ by the nanoparticle and it cannot strip one or two electrons from the nanoparticle and freely separate, resulting in bound complexes. Our analysis shows that a magnetic phase of iron oxide results from charge delocalization over the complex and a simultaneous interaction of the iron d-orbitals with the oxygen’s lone electrons and the nanoparticle’s reconstruction dimer-like defects. The core-shell integration at the nanoscale affords double functionality of luminescence and magnetism enhancing sensing, tracking, and delivery and enabling a variety of applications, including controlled drug delivery, underground oil and water exploration, and recovery.

Genetic diversity and Agro-climatic conditions contribute significantly to the agronomic and morphological features of the food plant species, and their nutraceutical potential. The present study was intended to evaluate the impact of growing conditions on total phenolic and total flavonoid contents, and in vitro antioxidant potential in the bulbs and leaves of onion varieties planted under diverse environmental conditions. Standard analytical methods were used to quantify total phenolic content (TPC), total flavonoid content (TFC), and free radicals’ scavenging/antioxidant capacity. The impact of climatic and soil conditions was assessed using statistical tools. In general, onion varieties cultivated at three different locations viz. Kalar Kahar, Lahore and Swabi exhibited significant variations in TPC and TFC, and antioxidant activities. The bulbs and leaves of Mustang (V1) variety planted at Lahore and Swabi had significantly (p < 0.05), high levels of TPC (659.5 ± 6.59, and 631.1 ± 8.58 mg GAE/100 g, respectively). However, leaves of Red Orb (V2) and bulbs of Mustang (V1), and Golden Orb (V6), harvested from Kalar Kahar depicted the highest concentration of TFC (432.5 ± 10.3, 303.0 ± 6.67, and 303.0 ± 2.52 mg QE/100 g DW, respectively). Likewise, bulbs of V1 planted at Kalar Kahar, Lahore and Swabi exhibited maximum inhibition of DPPH, ABTS, and H2O2 radicals (79.01 ± 1.49, 65.38 ± 0.99, and 59.76 ± 0.90%, respectively). Golden Orb (V6) harvested from Lahore had the highest scavenging of OH radical (67.40 ± 0.09%). Likewise, bulbs of V1 variety planted at KalarKahar and Swabi had significant capacity to scavenge ferric ions (415.1 ± 10.6 mg GAE/100 g DW), and molybdate ions (213.7 ± 0.00 mg AAE/100 g DW). Conversely, leaves of Amazon (V8), planted at Lahore and Swabi depicted significant levels of DPPH, ABTS, H2O2 radical scavenging (90.69 ± 0.26, 63.55 ± 1.06, 51.86 ± 0.43%, respectively), and reduction of ferric ions (184.2 ± 6.75 mg GAE/100 g DW). V6 leaves harvested from Lahore and that of Super Sarhad (V3) from Swabi showed the highest inhibition of OH radical (61.21 ± 0.79%), and molybdate ions (623.6 ± 0.12 mg AAE/100 g DW), respectively. Pearson correlation and principal component analysis revealed strong relationships of climatic conditions, soil properties and elevation with TPC, TFC and free radicals’ scavenging potential in the bulbs and leaves of onion varieties. The variations in the total phenolic and flavonoid contents, and antioxidant potential of different varieties, and their associations with climatic and soil factors revealed the complexity of the growing conditions and genetic makeup that imposed significant impacts on the synthesis of secondary metabolites and nutraceutical potential of food and medicinal plant species.

Hydrochemical characteristics and aquifer properties present a better understanding of the mitigation of groundwater pollution, which has become one of the leading environmental concerns and threats to the sustainable ecosystem. Seventy-seven groundwater samples were collected from Sargodha District (Pakistan) and characterized for their physical and chemical properties. The analytical data were processed for the evaluation of the processes that control the groundwater chemistry using various drinking and agricultural indices with statistical and hydrochemical modeling. The predominant hydrochemical type was found to be Ca-HCO3 type, followed by Na-HCO3 and Mg-Ca-Cl types. The present study showed that the main factors controlling the groundwater chemistry were the prevalent rock dominance alongside the weathering of silicates, solubilization of carbonates, and cation exchange processes. Entropy water quality index (EWQI) revealed that 6.51% represented “poor water,” while 7.79% were considered “extremely poor” for drinking purposes. However, USSL classification, Wilcox diagram, and other agricultural indices (RCS, SAR, %Na, MH, PI, and PS) showed that the majority of the samples were classified as suitable for irrigation purpose. However, 16% of the samples for %Na and 24% of the samples for MH were not suitable for agricultural purposes. Overall, the groundwater quality was affected by the anthropogenic stress in the study area.

BACKGROUND:Diagnosis of leprosy mainly relies on clinical examination due to the inconsistent sensitivity and poor reproducibility of the current laboratory tests. Utilisation of alternative methods to the standard Ziehl Neelsen (ZN), Fite-Faraco (FF) and Haematoxylin and Eosin (H&E) staining procedures may eventually improve leprosy diagnosis. METHODOLOGY/PRINCIPAL FINDINGS:In this comparative study, the performance of the fluorescent Auramine O (AO) staining and polymerase chain reaction (PCR) was assessed with different skin samples using a combination of ZN, FF and H&E staining as the gold standard. AO, ZN, FF, H&E and PCR tests were performed on slit skin smears (SSS) and/or punch biopsies collected from 141 clinically confirmed leprosy cases and 28 non-leprosy skin samples. DNA was extracted from punch biopsies using two different methods with or without mechanical lysis. Sensitivities were 87.6%, 59.3% and 77% for H&E, ZN and FF, respectively, whereas it reached 65.5% and 77.9% for AO in SSS and tissue sections and 91.1% for PCR in tissue samples. Morover, samples with low bacillary index, sensitivity of AO staining (61.8%) was similar to FF (60%, p>0.05) and lower than PCR (86.6%, p

Leprosy reactions are a significant cause of morbidity in leprosy population. Erythema nodosum leprosum (ENL) is an immunological complication affecting approximately 50% of patients with lepromatous leprosy (LL) and 10% of borderline lepromatous (BL) leprosy. ENL is associated with clinical features such as skin lesions, neuritis, arthritis, dactylitis, eye inflammation, osteitis, orchitis, lymphadenitis and nephritis. ENL is treated mainly with corticosteroids and corticosteroids are often required for extended periods of time which may lead to serious adverse effects. High mortality rate and increased morbidity associated with corticosteroid treatment of ENL has been reported. For improved and evidence-based treatment of ENL, documenting the systems affected by ENL is important. We report here the clinical features of ENL in a cohort of patients with acute ENL who were recruited for a clinico-pathological study before and after prednisolone treatment.A case-control study was performed at ALERT hospital, Ethiopia. Forty-six LL patients with ENL and 31 non-reactional LL matched controls were enrolled to the study and followed for 28 weeks. Clinical features were systematically documented at three visits (before, during and after predinsolone treatment of ENL cases) using a specifically designed form. Skin biopsy samples were obtained from each patient before and after treatment and used for histopathological investigations to supplement the clinical data.Pain was the most common symptom reported (98%) by patients with ENL. Eighty percent of them had reported skin pain and more than 70% had nerve and joint pain at enrolment. About 40% of the patients developed chronic ENL. Most individuals 95.7% had nodular skin lesions. Over half of patients with ENL had old nerve function impairment (NFI) while 13% had new NFI at enrolment. Facial and limb oedema were present in 60% patients. Regarding pathological findings before treatment, dermal neutrophilic infiltration was noted in 58.8% of patients with ENL compared to 14.3% in LL controls. Only 14.7% patients with ENL had evidence of vasculitis at enrolment.In our study, painful nodular skin lesions were present in all ENL patients. Only 58% patients had dermal polymorphonuclear cell infiltration showing that not all clinically confirmed ENL cases have neutrophilic infiltration in lesions. Very few patients had histological evidence of vasculitis. Many patients developed chronic ENL and these patients require inpatient corticosteroid treatment for extended periods which challenges the health service facility in resource poor settings, as well as the patient's quality of life.

BACKGROUND:Erythema Nodosum Leprosum (ENL) is a serious complication of leprosy. It is normally treated with high dose steroids, but its recurrent nature leads to prolonged steroid usage and associated side effects. There is little evidence on the efficacy of alternative treatments for ENL, especially for patients who have become steroid resistant or have steroid side effects. These two pilot studies compare the efficacy and side effect profile of ciclosporin plus prednisolone against prednisolone alone in the treatment of patients with either new ENL or chronic and recurrent ENL. METHODS AND RESULTS:Thirteen patients with new ENL and twenty patients with chronic ENL were recruited into two double-blinded randomised controlled trials. Patients were randomised to receive ciclosporin and prednisolone or prednisolone treatment only. Patients with acute ENL had a delay of 16 weeks in the occurrence of ENL flare-up episode, with less severe flare-ups and decreased requirements for additional prednisolone. Patients with chronic ENL on ciclosporin had the first episode of ENL flare-up 4 weeks earlier than those on prednisolone, as well as more severe ENL flare-ups requiring 2.5 times more additional prednisolone. Adverse events attributable to prednisolone were more common that those attributable to ciclosporin. CONCLUSIONS:This is the first clinical trial on ENL management set in the African context, and also the first trial in leprosy to use patients' assessment of outcomes. Patients on ciclosporin showed promising results in the management of acute ENL in this small pilot study. But ciclosporin, did not appear to have a significant steroid-sparing effects in patients with chronic ENL, which may have been due to the prolonged use of steroids in these patients in combination with a too rapid decrease of steroids in patients given ciclosporin. Further research is needed to determine whether the promising results of ciclosporin in acute ENL can be reproduced on a larger scale.

Background: Numerous epidemiological studies have suggested that metal exposure may promote the atherosclerosis disorder in humans. Objective: This study is carried out to assess the distribution, correlation and multivariate apportionment of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), lead (Pb) and zinc (Zn) in the blood of atherosclerosis patients in comparison with healthy donors. Method: The quantification of metals is done by atomic absorption spectrometry, after wet-acid digestion of the blood samples. Results: Significantly higher concentrations of cadmium, chromium, copper, iron and manganese are found in the blood of atherosclerosis patients. The correlation study shows diverse relationships among the metals in blood of the patients and controls. Multivariate cluster analysis based on the metal levels in patients and controls reveals clearly separate grouping for the patients and healthy donors. Moreover, principal component analysis shows divergent grouping of the metals for the patients and healthy donors, which may be associated with the altered metabolism of the metals in atherosclerosis patients. Conclusion: Overall, the distribution, correlation and multivariate apportionment of selected metals in atherosclerosis patients and healthy donors are significantly divergent. Hence, present findings suggest that the trace and redox metals accumulated in the body may pose a high risk for atherosclerosis development.

Composite water samples were collected from different sites of Mangla reservoir, Pakistan, in premonsoon, monsoon, and postmonsoon seasons. The physicochemical parameters and trace/heavy metals were determined in all water samples. The results manifested significant seasonal variations among Co, Cr, Ni, and Pb and the metals exhibited highest contribution in premonsoon season except Mn. Principal component analysis (PCA) and cluster analysis (CA) revealed considerable anthropogenic intrusions in the reservoir. Probable risk associated with the metals levels on human health was also evaluated using hazard quotients (HQ) by ingestion and dermal routes for adults and children. It was noted that Cd, Co, Cr, Ni, and Pb (HQing>1) were the most important pollutants leading to noncarcinogenic concerns. The HQderm levels of all metals were below unity, suggesting that these metals posed no hazards via dermal absorption, while the oral intake was the major exposure pathway. The largest contributors to chronic risks were Cd, Co, Cr, Ni, and Pb in all the seasons. Therefore, immediate measures should be taken for sustaining the healthy aquatic ecosystem.

Composite soil samples collected from suburban areas were analyzed for Cd, Co, Cr, Cu, Fe, Mn, Pb, Sr, and Zn by atomic absorption spectrophotometry. Based on pseudototal metal analysis, Fe, Mn, Sr, and Zn were the prevailing metals while Cd, Co, Cr, and Pb were the least participants. However, based on bioavailability, Cd, Co, Pb, and Sr were easily leachable and might pose adverse effects to soil biota. In ecological risk assessment, contamination factor demonstrated moderate contamination by Co, Sr, and Zn and high contamination by Cd, Cu, and Pb; geoaccumulation index indicated heavy to extreme contamination by Cd and heavy contamination by Pb; enrichment factor revealed significant enrichment by Co, Cr, Cu, Mn, Sr, and Zn and extreme enrichment by Cd and Pb. Substantial human inputs for Cd, Co, Cr, Cu, Mn, Pb, Sr, and Zn were also revealed by principal component analysis in the examined soil. Overall the study area was found to be contaminated at considerable/high degree.

The present study is carried out for the assessment of water quality parameters and selected metals levels in surface water from Mangla Lake, Pakistan. The metal levels (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Sr, and Zn) were determined by flame atomic absorption spectrophotometry. Average levels of Cd, Co, Cr, Ni, and Pb were higher than the allowable concentrations set by national and international agencies. Principal component analysis indicated significant anthropogenic contributions of Cd, Co, Cr, Ni, and Pb in the water reservoir. Noncarcinogenic risk assessment was then evaluated using Hazard Quotient HQing/derm and Hazard Index HIing/derm following USEPA methodology. For adults and children, Cd, Co, Cr, and Pb HQing>1 emerged as the most important pollutants leading to noncarcinogenic concerns via ingestion route, whereas there was no risk via dermal contact of surface water. This study helps in establishing pollutant loading reduction goal and the total maximum daily loads, and consequently contributes to preserve public health and develop water conservation strategy.

A new variety of zinc biofortified wheat (Zincol-2016) was released in Pakistan in 2016. The primary aim of this study was to examine the effects of consuming Zincol-2016 wheat flour on biochemical and functional markers of zinc status in a population with widespread zinc deficiency. An individually-randomised, double-blind, placebo-controlled cross over design was used. Fifty households were recruited to participate in the study, with each household included at least one woman of reproductive age (16-49 years) who was neither pregnant nor breast feeding or currently taking nutritional supplements. All households were provided with control flour for an initial 2-week baseline period, followed by the intervention period where households were randomly allocated in a 1:1 ratio to receive biofortified flour (group A; n = 25) and control flour (group B; n = 25) for 8-weeks, then switched to the alternate flour for 8-weeks. The trial has been registered with the ISRCTN (https://www.isrctn.com), ID ISRCTN83678069. The primary outcome measure was plasma zinc concentration, and the secondary outcome measures were plasma selenium and copper concentrations, plasma copper:zinc ratio and fatty acid desaturase and elongase activity indices. Nutrient intake was assessed using 24-h dietary recall interviews. Mineral concentrations in plasma were measured using inductively coupled plasma mass spectrometry and free fatty acids and sphingolipids by mass spectrometry. Linear Mixed Model regression and General Linear Model with repeated measures were used to analyse the outcomes. Based on an average flour consumption of 224 g/day, Zincol-2016 flour provided an additional daily zinc intake of between 3.0 and 6.0 mg for white and whole grain flour, respectively. No serious adverse events were reported. This resulted in significant, increase in plasma zinc concentration after 4 weeks [mean difference 41.5 μg/L, 95% CI (6.9-76.1), p = 0.02]. This was not present after 8 weeks (p = 0.6). There were no consistent significant effects of the intervention on fatty acid desaturase and elongase activity indices. Regular consumption of Zincol-2016 flour increased the daily zinc intake of women of reproductive age by 30-60%, however this was not associated with a sustained improvement in indices of zinc status.