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Faidutti C, Doolette C, Hair L, van Daalen KR, Naheed A, Lombi E, Feldmann J. Trace Element Distribution and Arsenic Speciation in Toenails as Affected by External Contamination and Evaluation of a Cleaning Protocol. Anal Chem 2024; 96:4039-4047. [PMID: 38422552 PMCID: PMC10938283 DOI: 10.1021/acs.analchem.3c03962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 11/11/2023] [Accepted: 11/16/2023] [Indexed: 03/02/2024]
Abstract
Trace element concentrations in toenail clippings have increasingly been used to measure trace element exposure in epidemeological research. Conventional methods such as inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography ICP-MS (HPLC-ICP-MS) are commonly used to measure trace elements and their speciation in toenails. However, the impact of the removal of external contamination on trace element quantification has not been thoroughly studied. In this work, the microdistribution of trace elements (As, Ca, Co, Cu, Fe, K, Mn, Ni, Rb, S, Sr, Ti, and Zn) in dirty and washed toenails and the speciation of As in situ in toenails were investigated using synchrotron X-ray fluorescence microscopy (XFM) and laterally resolved X-ray absorption near edge spectroscopy (XANES). XFM showed different distribution patterns for each trace element, consistent with their binding properties and nail structure. External (terrestrial) contamination was identified and distinguished from the endogenous accumulation of trace elements in toenails─contaminated areas were characterized by the co-occurrence of Co, Fe, and Mn with elements such as Ti and Rb (i.e., indicators of terrestrial contamination). The XANES spectra showed the presence of one As species in washed toenails, corresponding to As bound to sulfhydryl groups. In dirty specimens, a mixed speciation was found in localized areas, containing AsIII-S species and AsV species. ArsenicV is thought to be associated with surface contamination and exogenous As. These findings provide new insights into the speciation of arsenic in toenails, the microdistribution of trace elements, and the effectiveness of a cleaning protocol in removing external contamination.
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Affiliation(s)
- Camilla Faidutti
- TESLA,
Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, U.K.
| | - Casey Doolette
- Future
Industries Institute, University of South
Australia, Mawson
Lakes, SA 5095, Australia
| | - Louise Hair
- TESLA,
Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, U.K.
| | | | | | - Enzo Lombi
- Future
Industries Institute, University of South
Australia, Mawson
Lakes, SA 5095, Australia
| | - Joerg Feldmann
- TESLA
− Analytical Chemistry, Institute of Chemistry, University of Graz, Graz 8010, Austria
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2
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Maria de Moura Feitosa Veras J, de Siqueira Coelho L, Pinto Medeiros Neto L, Modesto de Almeida R, Carlos da Silva G, Bachion de Santana F, Assis Garcia L, Abrahao Martin A, Pereira Favero P. Identification of biomarkers in diabetic nails by Raman spectroscopy. Clin Chim Acta 2023; 544:117363. [PMID: 37100189 DOI: 10.1016/j.cca.2023.117363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/13/2023] [Accepted: 04/19/2023] [Indexed: 04/28/2023]
Abstract
BACKGROUND The growth of Diabetes Mellitus (DM) is a serious public health issue which is more prevalent in developing countries. The main problems related to DM are the gradual changes in the structural and functional integrity of tissues caused by hyperglycemia, which calls for early diagnosis and periodic monitoring exams. Recent studies suggest that the quality of the nail plate has great potential to assess the secondary complications of DM. Hence, this study aimed to determine the biochemical characteristics of the nails of individuals with DM2 by Raman confocal spectroscopy (CRS). METHODS We collected fragments from the distal region of the fingernails of 30 healthy volunteers and 30 volunteers with DM2. The samples were analyzed by CRS (Xplora - Horiba) coupled to a 785 nm laser. RESULTS Alterations in different biochemical components, such as proteins, lipids, amino acids, and final agents of advanced glycation, and alterations in the disulfide bridges, which are important in stabilizing keratin in nails were identified. CONCLUSION The spectral signatures and new DM2 markers in nails were identified. Therefore, the possibility of acquiring biochemical information by evaluating the nails of diabetics, a simple and easily acquired material associated with the CRS technique, may allow health complications to be detected quickly.
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Affiliation(s)
| | | | | | | | | | - Felipe Bachion de Santana
- Enviroment, Soils and Land Use Department, Teagasc, Johnstown Castle Research Centre, Wexford, Ireland
| | | | - Airton Abrahao Martin
- Universidade Brasil, São Paulo - São Paulo, Brasil; DermoPROBES - Skin and Hair Technology, São José dos Campos, São Paulo, Brasil
| | - Priscila Pereira Favero
- Universidade Brasil, São Paulo - São Paulo, Brasil; DermoPROBES - Skin and Hair Technology, São José dos Campos, São Paulo, Brasil
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3
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Petrokilidou C, Gaitanis G, Velegraki A, Bassukas ID, Kourkoumelis N. Treatment of nail clippings with ethyl alcohol improves the efficacy of Raman spectroscopy in the diagnosis of Trichophyton rubrum onychomycosis. JOURNAL OF BIOPHOTONICS 2023:e202300040. [PMID: 37071082 DOI: 10.1002/jbio.202300040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/11/2023] [Accepted: 04/14/2023] [Indexed: 06/19/2023]
Abstract
The purpose of this work was to enhance the diagnostic accuracy of nail Raman spectroscopy for fungal nail infections, specifically onychomycosis caused by Trichophyton rubrum. The study assessed the different ethyl alcohol retention rates between control and infected nails after soaking nail clippings in ethanolic solutions and drying. Results revealed that ethyl alcohol completely evaporated from infected nail samples, while significant amounts were still present in control samples. Principal component analysis (PCA) was applied to discriminate control from infected nails and showed superior group separation when nails were treated with ethyl alcohol. PCA loadings plot attributed the efficient classification to the νs (CCO) Raman vibrational mode of ethyl alcohol. As Raman spectroscopy can detect minute concentration changes of ethyl alcohol in nails and the deterioration caused by onychomycosis accelerates its evaporation, a simple and rapid method for detecting T. rubrum onychomycosis is proposed.
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Affiliation(s)
- Chrysoula Petrokilidou
- Department of Medical Physics, School of Health Sciences, University of Ioannina, Ioannina, Greece
| | - Georgios Gaitanis
- Department of Skin and Venereal Diseases, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina, Greece
| | - Aristea Velegraki
- Mycology Research Laboratory and UOA/HCPF Culture Collection, Microbiology Department, Medical School, National and Kapodistrian University of Athens, Athens, Greece
- Mycology Laboratory, BIOMEDICINE S.A., Athens, Greece
| | - Ioannis D Bassukas
- Department of Skin and Venereal Diseases, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina, Greece
| | - Nikolaos Kourkoumelis
- Department of Medical Physics, School of Health Sciences, University of Ioannina, Ioannina, Greece
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4
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Krawczyk-Santos AP, da Rocha PBR, Kloppel LL, Souza BDS, Anjos JLV, Alonso A, de Faria DLA, Gil OM, Gratieri T, Marreto RN, Taveira SF. Enhanced nail delivery of voriconazole-loaded nanomicelles by thioglycolic acid pretreatment: A study of protein dynamics and disulfide bond rupture. Int J Pharm 2021; 602:120597. [PMID: 33862134 DOI: 10.1016/j.ijpharm.2021.120597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/03/2021] [Accepted: 04/08/2021] [Indexed: 10/21/2022]
Abstract
This work aimed to select an effective penetration enhancer (PE) for nail pretreatment, develop voriconazole (VOR)-loaded nanomicelles, and evaluate their ability to deliver VOR to the nail. A complete analysis of nail protein dynamics, bond rupture, and microstructure was performed. Alternative methods as electron paramagnetic resonance (EPR) and the Ellman's reagent (DTNB) assay were also evaluated. Nanomicelles were produced and characterized. The PE hydrated the hooves, following the order: urea ≈ cysteine ≈ glycolic acid < thioglycolic acid (TGA) < NaOH. SEM images and methylene blue assay showed enlarged pores and roughness of porcine hooves after incubation with NaOH and TGA. EPR was demonstrated to be the most sensitive technique. DTNB assay quantified higher thiol groups for samples treated with TGA (p < 0.05). A stratigraphic analysis with Raman spectroscopy demonstrated that hooves treated with TGA presented a higher SH/SS ratio at the edges, affecting protein secondary structure. In vitro permeation studies demonstrated significant VOR permeation (29.44 ± 6.13 µg/cm2), 10-fold higher than previous studies with lipid nanoparticles. After TGA pretreatment, VOR permeation was further enhanced (3-fold). TGA pretreatment followed by VOR-loaded nanomicelles demonstrates a promising approach for onychomycosis treatment. The novel methods for protein analysis were straightforward and helpful.
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Affiliation(s)
- Anna Paula Krawczyk-Santos
- Laboratory of Nanosystems and Drug Delivery Devices (NanoSYS), School of Pharmacy, Universidade Federal de Goiás (UFG), Rua 240, esq. com 5ª Avenida, Setor Leste Universitário, 74605-170 Goiânia, GO, Brazil
| | - Priscila B R da Rocha
- Laboratory of Nanosystems and Drug Delivery Devices (NanoSYS), School of Pharmacy, Universidade Federal de Goiás (UFG), Rua 240, esq. com 5ª Avenida, Setor Leste Universitário, 74605-170 Goiânia, GO, Brazil
| | - Leandro L Kloppel
- Laboratory of Nanosystems and Drug Delivery Devices (NanoSYS), School of Pharmacy, Universidade Federal de Goiás (UFG), Rua 240, esq. com 5ª Avenida, Setor Leste Universitário, 74605-170 Goiânia, GO, Brazil
| | - Bruno Dos S Souza
- Laboratory of Nanosystems and Drug Delivery Devices (NanoSYS), School of Pharmacy, Universidade Federal de Goiás (UFG), Rua 240, esq. com 5ª Avenida, Setor Leste Universitário, 74605-170 Goiânia, GO, Brazil
| | - Jorge Luiz V Anjos
- Physics Department, Universidade Federal de Catalão (UFCAT), Catalão, GO, Brazil
| | - Antonio Alonso
- Biophysics Department, Universidade Federal de Goiás (UFG), Goiânia, GO, Brazil
| | - Dalva Lúcia A de Faria
- Laboratory of Molecular Spectroscopy, Institute of Chemistry, Universidade de São Paulo (USP), Av. Prof. Lineu Prestes 748, Butantã, 05508-000 São Paulo, SP, Brazil
| | - Otávio M Gil
- Laboratory of Molecular Spectroscopy, Institute of Chemistry, Universidade de São Paulo (USP), Av. Prof. Lineu Prestes 748, Butantã, 05508-000 São Paulo, SP, Brazil
| | - Tais Gratieri
- Laboratory of Food, Drugs and Cosmetics (LTMAC), School of Health Sciences, Universidade de Brasilia (UnB), Campus Universitário Darcy Ribeiro, Asa Norte, 70, 910-900 Brasília - DF, Brazil
| | - Ricardo N Marreto
- Laboratory of Nanosystems and Drug Delivery Devices (NanoSYS), School of Pharmacy, Universidade Federal de Goiás (UFG), Rua 240, esq. com 5ª Avenida, Setor Leste Universitário, 74605-170 Goiânia, GO, Brazil
| | - Stephania Fleury Taveira
- Laboratory of Nanosystems and Drug Delivery Devices (NanoSYS), School of Pharmacy, Universidade Federal de Goiás (UFG), Rua 240, esq. com 5ª Avenida, Setor Leste Universitário, 74605-170 Goiânia, GO, Brazil.
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Šveikauskaitė I, Briedis V. Potential of Naftifine Application for Transungual Delivery. Molecules 2020; 25:E3043. [PMID: 32635240 PMCID: PMC7411873 DOI: 10.3390/molecules25133043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/29/2020] [Accepted: 06/30/2020] [Indexed: 12/03/2022] Open
Abstract
Naftifine is used to treat fungal skin infections as it inhibits dermatophytes, which are the cause of onychomycosis. However, naftifine's ability to permeate the human nail barrier has not been investigated, thus, the antimycotic potential is not clearly established. This work aims to evaluate the effect of penetration enhancing factors on the accumulation of naftifine hydrochloride through human nail clippings. Naftifine polymeric nail lacquers with Eudragit RL100 were developed as a suitable delivery system. Low penetration of naftifine into nail has been determined as less than 10% of applied drug dose accumulated in the nail layers. Incorporation of thioglycolic acid into formulations resulted in increased accumulation of antifungal agent in the nail layers by 100% compared with a control group. Salicylic acid did not effect naftifine accumulation in the human nail. The permeation of naftifine through the nail increased by threefold when the thioglycolic acid-containing formulation was applied and the nail was pretreated with a fractional CO2 laser. Structural changes of the nail barrier, induced by fractional CO2 laser, were visualized by microscopy. The results suggest, that naftifine nail penetration could be significantly increased when physical and chemical enhancing factors are applied.
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Affiliation(s)
- Indrė Šveikauskaitė
- Department of Clinical Pharmacy, Lithuanian University of Health Sciences, Sukilėlių pr. 13, Kaunas 50161, Lithuania;
- Institute of Pharmaceutical Technologies, Lithuanian University of Health Sciences, Sukilėlių pr. 13, Kaunas 50161, Lithuania
| | - Vitalis Briedis
- Department of Clinical Pharmacy, Lithuanian University of Health Sciences, Sukilėlių pr. 13, Kaunas 50161, Lithuania;
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6
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Abstract
Onychomycosis is the most prevalent nail infection. Although it is not a life-threatening condition, it impacts the quality of life for many patients and often imposes a challenging diagnostic problem. The causative agents are dermatophytes, yeasts and non-dermatophytic moulds. Accurate and early diagnosis, including the identification of the causative species, is the key factor for rational therapy. Still, early diagnosis is not optimal as the current gold standard for the differentiation of the infectious agents is culture-based approaches. On the other hand, noninvasive optical technologies may enable differential diagnosis of nail pathologies including onychomycosis. When light penetrates and propagates along the nail tissue, it interacts in different ways with the components of either infected or healthy nail segments, providing a wealth of diagnostic information upon escaping the tissue. This review aims to assess alternative optical techniques for the rapid diagnosis of onychomycosis with a potential to monitor therapeutic response or even identify the fungal agent non-invasively and in real time in a clinical setting.
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7
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Kourkoumelis N, Gaitanis G, Velegraki A, Bassukas ID. Nail Raman spectroscopy: A promising method for the diagnosis of onychomycosis. An ex vivo pilot study. Med Mycol 2017; 56:551-558. [DOI: 10.1093/mmy/myx078] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 08/18/2017] [Indexed: 12/11/2022] Open
Affiliation(s)
- Nikolaos Kourkoumelis
- Department of Medical Physics, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
| | - Georgios Gaitanis
- Department of Skin and Venereal Diseases, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
| | - Aristea Velegraki
- Mycology Research Laboratory, Department of Microbiology, Medical School, National and Kapodistrian University of Athens, 11527, Athens, Greece
- Biomedicine SA, Athens 11526, Greece
| | - Ioannis D Bassukas
- Department of Skin and Venereal Diseases, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
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8
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Caneschi CA, Almeida AMD, Martins FJ, Hyaric ML, Oliveira MME, Macedo GC, Almeida MVD, Raposo NRB. In vitro antifungal activity of organic compounds derived from amino alcohols against onychomycosis. Braz J Microbiol 2017; 48:476-482. [PMID: 28237676 PMCID: PMC5498441 DOI: 10.1016/j.bjm.2016.12.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 12/07/2016] [Indexed: 02/08/2023] Open
Abstract
Onychomycosis is a fungal infection of the nail caused by high densities of filamentous fungi and yeasts. Treatment for this illness is long-term, and recurrences are frequently detected. This study evaluated in vitro antifungal activities of 12 organic compounds derived from amino alcohols against standard fungal strains, such as Trichophyton rubrum CCT 5507 URM 1666, Trichophyton mentagrophytes ATCC 11481, and Candida albicans ATCC 10231. The antifungal compounds were synthesized from p-hydroxybenzaldehyde (4a–4f) and p-hydroxybenzoic acid (9a–9f). Minimum inhibitory concentrations and minimum fungicidal concentrations were determined according to Clinical and Laboratory Standards Institute protocols M38-A2, M27-A3, and M27-S4. The amine series 4b–4e, mainly 4c and 4e compounds, were effective against filamentous fungi and yeast (MIC from 7.8 to 312 μg/mL). On the other hand, the amide series (9a–9f) did not present inhibitory effect against fungi, except amide 9c, which demonstrated activity only against C. albicans. This allowed us to infer that the presence of amine group and intermediate carbon number (8C–11C) in its aliphatic side chain seems to be important for antifungal activity. Although these compounds present cytotoxic activity on macrophages J774, our results suggest that these aromatic compounds might constitute potential as leader molecules in the development of more effective and less toxic analogs that could have considerable implications for future therapies of onychomycosis.
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Affiliation(s)
- César Augusto Caneschi
- Universidade Federal de Juiz de Fora, Faculdade de Farmácia, Núcleo de Pesquisa e Inovação em Ciências da Saúde (NUPICS), Juiz de Fora, MG, Brazil
| | - Angelina Maria de Almeida
- Universidade Federal de Juiz de Fora, Instituto de Ciências Exatas, Departamento de Química, Juiz de Fora, MG, Brazil
| | - Francislene Juliana Martins
- Universidade Federal de Juiz de Fora, Faculdade de Farmácia, Núcleo de Pesquisa e Inovação em Ciências da Saúde (NUPICS), Juiz de Fora, MG, Brazil
| | - Mireille Le Hyaric
- Universidade Federal de Juiz de Fora, Instituto de Ciências Exatas, Departamento de Química, Juiz de Fora, MG, Brazil
| | | | - Gilson Costa Macedo
- Universidade Federal de Juiz de Fora, Instituto de Ciências Biológicas, Departamento de Parasitologia, Microbiologia e Imunologia, Juiz de Fora, MG, Brazil
| | - Mauro Vieira de Almeida
- Universidade Federal de Juiz de Fora, Instituto de Ciências Exatas, Departamento de Química, Juiz de Fora, MG, Brazil
| | - Nádia Rezende Barbosa Raposo
- Universidade Federal de Juiz de Fora, Faculdade de Farmácia, Núcleo de Pesquisa e Inovação em Ciências da Saúde (NUPICS), Juiz de Fora, MG, Brazil.
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9
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Shin MK, Kim TI, Kim WS, Park HK, Kim KS. Changes in nail keratin observed by Raman spectroscopy after Nd:YAG laser treatment. Microsc Res Tech 2016; 80:338-343. [PMID: 27481603 DOI: 10.1002/jemt.22734] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 06/13/2016] [Accepted: 07/09/2016] [Indexed: 11/09/2022]
Abstract
Lasers and photodynamic therapy have been considered a convergence treatment for onychomycosis, which is a fungal infection on the nail bed and nail plate. Laser therapies have shown satisfactory results without significant complications for onychomycosis; however, the mechanism of clearing remains unknown. In this work, we investigated changes in the chemical structure of nail keratin induced by Nd:YAG laser using Raman spectroscopy. Toe nails with onychomycosis were treated with 1064 nm Nd:YAG laser. After laser treatment, the disulfide band (490-590 cm-1 ) of nail keratin was rarely observed or was reduced in intensity. The amide I band (1500-1700 cm-1 ) also showed changes induced by the laser. The α-helical (1652 cm-1 ) structures dominated the β-sheet (1673 cm-1 ) in nontreated nail, but the opposite phenomenon was observed after laser treatment.
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Affiliation(s)
- Min Kyung Shin
- Department of Dermatology, College of Medicine, Kyung Hee University, Seoul, Korea
| | - Tae In Kim
- Department of Dermatology, College of Medicine, Kyung Hee University, Seoul, Korea
| | - Wan Sun Kim
- Department of Biomedical Engineering, Graduate school, Kyung Hee University, Seoul, Korea
| | - Hun-Kuk Park
- Department of Biomedical Engineering, Graduate school, Kyung Hee University, Seoul, Korea.,Program of Medical Engineering, Kyung Hee University, Seoul, Korea.,Healthcare Industry Research Institute, Kyung Hee University, Seoul, Korea
| | - Kyung Sook Kim
- Department of Biomedical Engineering, Graduate school, Kyung Hee University, Seoul, Korea.,Program of Medical Engineering, Kyung Hee University, Seoul, Korea
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Abstract
Nail disorders are beyond cosmetic concern; besides discomfort in the performance of daily chores, they disturb patients psychologically and affect their quality of life. Fungal nail infection (onychomycosis) is the most prevalent nail-related disorder affecting a major population worldwide. Overcoming the impenetrable nail barrier is the toughest challenge for the development of efficacious topical ungual formulation. Sophisticated techniques such as iontophoresis and photodynamic therapy have been proven to improve transungual permeation. This article provides an updated and concise discussion regarding the conventional approach and upcoming novel approaches focused to alter the nail barrier. A comprehensive description regarding preformulation screening techniques for the identification of potential ungual enhancers is also described in this review while highlighting the current pitfalls for the development of ungual delivery.
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Zhang QB, Li C, Pan YT, Shan GH, Cao P, He J, Lin ZS, Ao NJ, Huang YX. Microstructure and mechanical properties of horns derived from three domestic bovines. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2013; 33:5036-43. [PMID: 24094221 DOI: 10.1016/j.msec.2013.08.034] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/17/2013] [Accepted: 08/27/2013] [Indexed: 11/18/2022]
Abstract
The microstructure and mechanical properties of horns derived from three domestic bovines (buffalo, cattle and sheep) were examined. The effects of water content, sampling position and orientation of three bovid horns on mechanical properties were systematically investigated by uniaxial tension and micron indentation tests. Meanwhile, the material composition and metal element contents were determined by Raman spectroscopy and elemental analysis respectively, and the microstructures of the horns were measured by scanning electron microscopy (SEM). Results show that the mechanical properties of horns have negative correlation with water contents and depend on sampling position and orientation. The spatial variations of the mechanical properties in horns are attributed to the different keratinization degrees in the proximal, middle and distal parts. And the mechanical properties of horns in the longitudinal direction are better than those in transverse. Among the three kinds of horns, the mechanical properties of buffalo horn are the best, followed by cattle horn, and those in sheep horn are the worst. This is due to the differences in material composition, metal element, and the microstructures of the horns. But the mechanical properties of buffalo horns are not dependent on the source of the buffalo. Therefore, regular engineered buffalo keratinous materials with standard mechanical properties can be obtained from different buffalo horns by using proper preparation methods.
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Affiliation(s)
- Quan-bin Zhang
- Department of Biomedical Engineering, Jinan University, Guangzhou 510632, PR China
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