A Further Study on Calcium Phosphate Gardens Grown from the Interface of κ-Carrageenan-based Hydrogels and Counterion Solutions

Originating from the concept of classical chemical gardens, a new field coined 'chemobrionics' has recently emerged. In the present work, two chemobrionic systems grown from a hydrogel/liquid interface at different time scales (for 1, 7, 14 or 28 days) were investigated, i. e., a calcium-based hydrogel with a phosphate counterion solution (Ca-gel) and a phosphate-based hydrogel with a calcium counterion solution (P-gel). The initial pH changes of the systems were investigated, and the obtained tubular structures were studied using optical microscopy, SEM, AFM, PXRD and TGA. One of the important findings is that the tubes obtained in the Ca-gel system were straight and long, which could be explained by the larger pH difference observed between the hydrogel and the counterion solution in this system (ΔpH∼2.1) compared to the P-gel system (ΔpH∼0). The Ca-gel structures remained overall more amorphous even though increased crystallinity was observed in both systems with increased time spent in counterion solution. Both systems contained hydroxyapatite phases, with additional calcite phases observed for the P-gel structures and traces of κ-carrageenan for the Ca-gel structures. Our study provides a promising method for controlling tubular macrostructures through adjusting the reaction conditions such as maturation time and pH.

Molecular Metallocorrole-Nanorod Photocatalytic System for Sustainable Hydrogen Production

Solar-driven photocatalytic generation of hydrogen from water is a potential source of clean and renewable fuel. Yet systems that are sufficiently stable and efficient for practical use have not been realized. Here, nanorod photocatalysts that have proven record activity for the water reduction half reaction were successfully combined with molecular metallocorroles suitable for catalyzing the accompanying oxidation reactions. Utilization of OH^- /⋅OH redox species as charge transfer shuttle between freely mixed metallocorroles and rods resulted in quantum efficiency that peaked as high as 17 % for hydrogen production from water in the absence of sacrificial hole scavengers. While typically each sacrificial scavenger is able to extract but a single hole, here the molecular metallocorrole catalysts were found to successfully handle nearly 300,000 holes during their lifespan. The implications of the new system on the prospects of realizing practical overall water splitting and direct solar-to-fuel energy conversion were discussed.

Synthesis, characterization, and humidity-responsiveness of guar gum xanthate and its nanocomposite with copper sulfide covellite

A novel conjugation of guar gum with xanthate groups via facile aqueous xanthation reaction has been reported. Density of grafted xanthate on guar gum product (GG-X) is as high as 4.4%, thus GG-X is conceivably characterized and confirmed by various spectrometric, electrochemical, thermogravimetric, and microscopic methods. Complexation of GG-X with numerous borderline and soft metal ions (e.g. Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺, Pb²⁺, Pt²⁺ and Cd²⁺) yields hydrophilic gel-like materials and shows good agreement with hard and soft acid and base (HSAB) theory. This indicates tremendous potential of GG-X in metal ion extraction, removal and hydrogel cross-linking. GG-X is also employed to formulate an aqueous colloidal dispersion of copper sulfide covellite (GG-X/CuS) nanocomposites. GG-X therefore behaves as a surfactant, allowing formation of electronically conductive nanocomposites. XRD indicates apparent beneficial effects of GG-X in the synthesis of CuS with a crystallite size of 15.6 nm. This novel nanocomposite is a promising material for humidity sensing, showing reversible linear responses to relative humidity changes within 10 to 80% range. The interaction between GG-X and water might cause changes in electrical permittivity of GG-X/CuS nanocomposite and/or electrical hopping conductivity between CuS nanoparticles.

Synthesis, characterization and biocompatibility of guar gum-benzoic acid

A novel chemical functionalization of guar gum (GG) by benzoic acid (BA) via nucleophilic substitution reaction in aqueous solution has been reported. BA moieties are chosen due to coordination chemistry of carboxylic acid moieties, hydrophobicity and intermolecular interaction of aromatic rings. The presence of conjugated BA on guar gum-benzoic acid (GG-BA) with grafting density of 5.5% is confirmed by ¹H NMR. Amorphous GG-BA with irregular morphology has been studied by UV-Vis, FTIR, XRD, SEM, TEM, TGA, computational chemistry and contact angle measurement. GG-BA in a concentration range from 0 to 4000 μg mL^-1 has good biocompatibility to mouse embryonic fibroblasts (MEF), human mammary epithelial cells (MCF-10A) after 48 and 72 h of treatment using WST-1 assay. GG-BA shows great potential for the development of biomaterials such as bioadhesives, hydrogels, and coacervates.

Introducing FDG PET/CT-guided chemoradiotherapy for stage III NSCLC in low- and middle-income countries: preliminary results from the IAEA PERTAIN trial

Purpose

Patients with stage III non-small-cell lung cancer (NSCLC) treated with chemoradiotherapy (CRT) in low- and middle-income countries (LMIC) continue to have a poor prognosis. It is known that FDG PET/CT improves staging, treatment selection and target volume delineation (TVD), and although its use has grown rapidly, it is still not widely available in LMIC. CRT is often used as sequential treatment, but is known to be more effective when given concurrently. The aim of the PERTAIN study was to assess the impact of introducing FDG PET/CT-guided concurrent CRT, supported by training and quality control (QC), on the overall survival (OS) and progression-free survival (PFS) of patients with stage III NSCLC.

Methods

The study included patients with stage III NSCLC from nine medical centres in seven countries. A retrospective cohort was managed according to local practices between January 2010 and July 2014, which involved only optional diagnostic FDG PET/CT for staging (not for TVD), followed by sequential or concurrent CRT. A prospective cohort between August 2015 and October 2018 was treated according to the study protocol including FDG PET/CT in treatment position for staging and multimodal TVD followed by concurrent CRT by specialists trained in protocol-specific TVD and with TVD QC. Kaplan–Meier analysis was used to assess OS and PFS in the retrospective and prospective cohorts.

Results

Guidelines for FDG PET/CT image acquisition and TVD were developed and published. All specialists involved in the PERTAIN study received training between June 2014 and May 2016. The PET/CT scanners used received EARL accreditation. In November 2018 a planned interim analysis was performed including 230 patients in the retrospective cohort with a median follow-up of 14 months and 128 patients in the prospective cohort, of whom 69 had a follow-up of at least 1 year. Using the Kaplan–Meier method, OS was significantly longer in the prospective cohort than in the retrospective cohort (23 vs. 14 months, p = 0.012). In addition, median PFS was significantly longer in the prospective cohort than in the retrospective cohort (17 vs. 11 months, p = 0.012).

Conclusion

In the PERTAIN study, the preliminary results indicate that introducing FDG PET/CT-guided concurrent CRT for patients with stage III NSCLC in LMIC resulted in a significant improvement in OS and PFS. The final study results based on complete data are expected in 2020.

Electronic supplementary material

The online version of this article (10.1007/s00259-019-04421-5) contains supplementary material, which is available to authorized users.

Dirofilariasis in Vietnam: A case report and brief review

This report describes a rare case of ophthalmic dirofilariasis in a 68-year-old woman with red and foreign body sensation in the pterygium on her right eye. Slit lamp examination demonstrated a long-slender worm moving in her pterygium. The worm was removed surgically and then identified as Diroflaria repens by sequence analysis of the small subunit ribosomal RNA (SSU) gene. The situation of dirofilariasis in Vietnam has been reviewed. Since the first described case in 2010 there have been thirteen cases reported that suggested the emerging trend of the disease. Most of the documented cases of human dirofilariasis recorded in Vietnam presented with ocular infections and the responsible agent was D. repens. With the increase of reported cases of human, much more attention should be paid on control as well as diagnosis and treatment of dirofilariasis in Vietnam.

Relative efficiency calibration for determining isotopic composition and age of HEU items by passive non-destructive gamma spectrometry

The observation of the 239 keV gamma line from ²³²U decay in high-enriched uranium (HEU) samples prompted us to utilize ²³²U (with main gamma energies of its daughters at 239, 583, 763, and 860 keV) as a mediator isotope for performing relative (intrinsic) efficiency calibration among ²³²U, ²³⁴U, ²³⁵U, ²³⁸U, and ²¹⁴Bi isotopes. By this way, the isotopic composition and age of HEU samples can be derived from activity ratios constituted between pairs of these isotopes on the basis of a common relative efficiency calibration curve. The method proved to be a useful tool for γ-spectrometric characterization of HEU items, especially of weapon grade, shielded uranium material.

The Combination of Hydrogen and Methanol Production through Artificial Photosynthesis-Are We Ready Yet?

Because 100 % quantum efficiency for the photosynthetic production of H₂ from H₂ O under visible illumination has been achieved recently, the oxidation of H₂ O to O₂ remains the bottleneck to the overall water-splitting reaction. Oxidation of CH₄ to CH₃ OH might be combined with water reduction instead, so that H₂ and CH₃ OH chemical fuels can be simultaneously produced through a one-step process under solar illumination. This combination would be a promising approach towards a more sustainable future of chemistry, in which developing different strategies for artificial photosynthesis is of paramount importance. By using free and adsorbed HO^. radicals on the semiconductor surface, CH₄ can be activated to H₃ C^. radicals and converted into CH₃ OH, respectively, with great selectivity up to 100 %. The present lack of efficient photosynthetic systems for the formation of H₂ and CH₃ OH from abundant H₂ O and CH₄ motivates future research for basic science and industrial applications.

The clinical spectrum of omega-5-gliadin allergy

BACKGROUND

IgE-mediated allergy to the wheat protein omega-5-gliadin (O5G) is associated with wheat-dependent exercise-induced anaphylaxis (WDEIA), where exercise acts as a cofactor, triggering anaphylaxis after wheat ingestion. The wider application of O5G-specific IgE (sIgE) testing has revealed that the manifestations of O5G allergy extend beyond WDEIA.

AIMS

This study documents clinical manifestations in a large series of patients with sIgE to O5G.

METHODS

A retrospective clinical audit was performed on adult patients with a positive O5G sIgE (>0.35kU/L) between 2007 and 2013 compared with a group who had negative O5G sIgE. Clinical characteristics and skin prick test (SPT) results were examined.

RESULTS

Sixty-seven patients were characterised, 26 of whom presented with food-dependent exercise-induced allergy, whilst others presented with exercise-induced symptoms without apparent food association (16/67), idiopathic anaphylaxis (10/67), food-induced allergic symptoms without exercise (10/67) or recurrent acute urticaria (5/67). Specific IgE to O5G had 91% sensitivity and 92% specificity for wheat-related allergic symptoms. SPT had sensitivity of 92% and specificity of 84%.

CONCLUSION

WDEIA is the most common manifestation of O5G allergy, but patients may present with a variety of allergic manifestations, and wheat allergy is not always obvious on history. Non-exercise cofactors or a lack of cofactors were identified in many patients. A distinctive feature of this allergy is that despite regular wheat ingestion, allergic reactions to wheat occur infrequently. Testing for sIgE to O5G should be considered in patients presenting with exercise-induced urticaria/anaphylaxis, idiopathic anaphylaxis and recurrent acute (but not chronic) urticaria.

Practical use of povidone-iodine antiseptic in the maintenance of oral health and in the prevention and treatment of common oropharyngeal infections

AIMS

To better inform medical practitioners on the role of antiseptics in oropharyngeal health and disease, this article focuses on povidone-iodine (PVP-I), an established and widely-available antiseptic agent.

METHODOLOGY

Review of the anti-infective profile, efficacy and safety of PVP-I in managing common upper respiratory tract infections such as the common cold, influenza and tonsillo-pharyngitis, as well as oral complications resulting from cancer treatment (oral mucositis), and dental conditions (periodontitis, caries).

RESULTS

Antiseptics with broad-spectrum anti-infective activity and low resistance potential offer an attractive option in both infection control and prevention. While there is some evidence of benefit of antiseptics in a variety of clinical settings that include dental and oral hygiene, dermatology, oncology, and pulmonology, there appears to be discordance between the evidence-base and practice. This is especially apparent in the management and prevention of oropharyngeal infections, for which the use of antiseptics varies considerably between clinical practices, and is in marked contrast to their dermal application, where they are extensively used as both a prophylaxis and a treatment of skin and wound infections, thus minimising the use of antibiotics.

CONCLUSION

The link between oral and oropharyngeal health status and susceptibility to infection has long been recognised. The high rates of antibiotic misuse and subsequent development of bacterial resistance (e.g. increasing vancomycin-resistant enterococci (VRE) and methicillin-resistant Staphylococcus aureus (MRSA)) in large parts of the world, especially across Asia Pacific, highlight the need for identifying alternative antimicrobials that would minimise the use of these medications. This, together with recent large-scale outbreaks of, for example, avian and swine influenza virus, further underline the importance of an increasing armamentarium for infection prevention and control.

Veganism, bone mineral density, and body composition: a study in Buddhist nuns

SUMMARY

This cross-sectional study showed that, although vegans had lower dietary calcium and protein intakes than omnivores, veganism did not have adverse effect on bone mineral density and did not alter body composition.

INTRODUCTION

Whether a lifelong vegetarian diet has any negative effect on bone health is a contentious issue. We undertook this study to examine the association between lifelong vegetarian diet and bone mineral density and body composition in a group of postmenopausal women.

METHODS

One hundred and five Mahayana Buddhist nuns and 105 omnivorous women (average age = 62, range = 50-85) were randomly sampled from monasteries in Ho Chi Minh City and invited to participate in the study. By religious rule, the nuns do not eat meat or seafood (i.e., vegans). Bone mineral density (BMD) at the lumbar spine (LS), femoral neck (FN), and whole body (WB) was measured by DXA (Hologic QDR 4500). Lean mass, fat mass, and percent fat mass were also obtained from the DXA whole body scan. Dietary calcium and protein intakes were estimated from a validated food frequency questionnaire.

RESULTS

There was no significant difference between vegans and omnivores in LSBMD (0.74 +/- 0.14 vs. 0.77 +/- 0.14 g/cm(2); mean +/- SD; P = 0.18), FNBMD (0.62 +/- 0.11 vs. 0.63 +/- 0.11 g/cm(2); P = 0.35), WBBMD (0.88 +/- 0.11 vs. 0.90 +/- 0.12 g/cm(2); P = 0.31), lean mass (32 +/- 5 vs. 33 +/- 4 kg; P = 0.47), and fat mass (19 +/- 5 vs. 19 +/- 5 kg; P = 0.77) either before or after adjusting for age. The prevalence of osteoporosis (T scores < or = -2.5) at the femoral neck in vegans and omnivores was 17.1% and 14.3% (P = 0.57), respectively. The median intake of dietary calcium was lower in vegans compared to omnivores (330 +/- 205 vs. 682 +/- 417 mg/day, P < 0.001); however, there was no significant correlation between dietary calcium and BMD. Further analysis suggested that whole body BMD, but not lumbar spine or femoral neck BMD, was positively correlated with the ratio of animal protein to vegetable protein.

CONCLUSION

These results suggest that, although vegans have much lower intakes of dietary calcium and protein than omnivores, veganism does not have adverse effect on bone mineral density and does not alter body composition.

Common exostectomies of the rearfoot

A review of literature for first metatarsocuneiform joint exostosis, accessory navicular bone, Haglund's syndrome, and os trigonum syndrome does not reveal any significant changes in the process of diagnosis and treatment. The surgical procedures are simple to perform but complications do occur that necessitate the understanding of the pathology and anatomy for each condition.