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1.
Pak J Med Sci ; 35(6): 1669-1673, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31777513

RESUMO

BACKGROUND & OBJECTIVE: Cutaneous leishmaniasis (CL) is endemic in developing countries like Pakistan. Pentavalent antimonials are still drug of choice, despite being toxic and intolerable for patients. Second line treatments have been extensively studied but the results of their efficacy are conflicting. This, to our knowledge, will be the first study in this regard. Our objective was to determine if combination of oral itraconazole with intralesional (IL) meglumine antimoniate (MA) reduces the duration of treatment for cutaneous leishmaniasis, as compared to intralesional MA alone. METHODS: A randomized controlled trial (single blinded) was carried out from August 2017 till December 2017 on 69 patients who fulfilled inclusion criteria. They were assigned to Group-A or B by lottery method. Group-A patients received IL MA once a week while Group-B received oral itraconazole 200mg, once daily, for six weeks along with similar regimen of IL MA as Group-A. The patients were assessed every three weeks by the blinded assessor till clinical cure was achieved. A follow up visit, two months after clinical cure was done to look for relapse of the disease. RESULTS: Thirty patients in Group-A and 35 patients in Group-B completed the study. At 3, 6, 9 and 12 weeks the patients were assessed for: no, partial or complete response and results of the two groups were compared for statistical significance. The p-values of 0.20, 0.57 and 0.11 at 3, 6 and 9 weeks, respectively, depict that there was no significant difference at any step of assessment between the two groups in terms of healing. The p values of each t test was>0.05 refuting the hypothesis. CONCLUSION: Combination of oral itraconazole with intralesional MA offered no benefit over intralesional MA alone in the management of cutaneous leishmaniasis in terms of duration of therapy.

2.
Polymers (Basel) ; 16(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38475263

RESUMO

This study focuses on evaluating the fatigue life performance of 3D-printed polymer composites produced through the fused deposition modelling (FDM) technique. Fatigue life assessment is essential in designing components for industries like aerospace, medical, and automotive, as it provides an estimate of the component's safe service life during operation. While there is a lack of detailed research on the fatigue behaviour of 3D-printed polymer composites, this paper aims to fill that gap. Fatigue tests were conducted on the 3D-printed polymer composites under various loading conditions, and static (tensile) tests were performed to determine their ultimate tensile strength. The fatigue testing load ranged from 80% to 98% of the total static load. The results showed that the fatigue life of the pressed samples using a platen press was significantly better than that of the non-pressed samples. Samples subjected to fatigue testing at 80% of the ultimate tensile strength (UTS) did not experience failure even after 1 million cycles, while samples tested at 90% of UTS failed after 50,000 cycles, with the failure being characterized as splitting and clamp area failure. This study also included a lap shear analysis of the 3D-printed samples, comparing those that were bonded using a two-part Araldite glue to those that were fabricated as a single piece using the Markforged Mark Two 3D printer. In summary, this study sheds light on the fatigue life performance of 3D-printed polymer composites fabricated using the FDM technique. The results suggest that the use of post-printing platen press improved the fatigue life of 3D-printed samples, and that single printed samples have better strength of about 265 MPa than adhesively bonded samples in which the strength was 56 MPa.

3.
Polymers (Basel) ; 14(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35406250

RESUMO

In this study, Strontium (Sr) and Zinc (Zn) doped-HA nanoparticles were synthesized and incorporated into polyetheretherketone (PEEK) up to 30 wt.% and processed by a novel approach i.e., fused deposition modelling (FDM) 3D printing for the production of patient specific cranial implants with improved bioactivity and the required mechanical performance. Filaments were produced via extrusion and subsequently 3D-printed using FDM. To further improve the bioactivity of the 3D-printed parts, the samples were dip-coated in polyethylene glycol-DOPA (PEG-DOPA) solution. The printing quality was influenced by filler loading, but was not significantly influenced by the nature of doped-HA. Hence, the printing conditions were optimized for each sample. Micro-CT and Scanning Electron Microscopy (SEM) showed a uniform distribution of bioceramic particles in PEEK. Although agglomeration of particles increased with increase in filler loadings. Differential Scanning Calorimetry (DSC) showed that the melting point and crystallinity of PEEK increased with an increase in doped-HA loading from 343 °C to 355 °C and 27.7% to 34.6%, respectively. Apatite formation was confirmed on the 3D-printed samples after immersion in simulated body fluid (SBF) for 7, 14 and 28 days via SEM, X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The tensile strength and impact strength decreased from 75 MPa to 51 MPa and 14 kJ/m2 to 4 kJ/m2, respectively, while Young's modulus increased with increasing doped-HA content from 2.8 GPa to 4.2 GPa. However, the tensile strengths of composites remained in the range of human cortical bone i.e., ≥50 MPa. In addition, there was a slight increase in mechanical strength after 28 days immersion which was attributed to apatite formation. Water contact angle showed that the hydrophilicity of the samples improved after coating the 3D-printed samples with PEG-DOPA. Hence, based on the results, the 3D-printed PEEK nanocomposites with 20 wt.% doped-HA is selected as the best candidate for the 3D-printing of craniomaxillofacial implants.

4.
J Mech Behav Biomed Mater ; 121: 104601, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34077906

RESUMO

Polyetheretherketone (PEEK) is a biocompatible polymer widely used for biomedical applications. Because it is biologically inert, bioactive phases, such as nano-hydroxyapatite (HA), have been added to PEEK in order to improve its bioactivity. 3D printing (3DP) technologies are being increasingly used today to manufacture patient specific devices and implants. However, processing of PEEK is challenging due to its high melting point which is above 340 °C. In this study, PEEK-based filaments containing 10 wt% of pure nano-HA, strontium (Sr)- doped nano-HA and Zinc (Zn)-doped nano-HA were produced via hot-melt extrusion and subsequently 3D printed via fused deposition modelling (FDM), following an initial optimization process. The raw materials, extruded filaments and 3D printed samples were characterized in terms of physicochemical, thermal and morphological analysis. Moreover, the mechanical performance of 3D printed specimens was assessed via tensile tensing. Although an increase in the melting point and a reduction in crystallization temperature was observed with the addition of HA and doped HA to pure PEEK, there was no noticeable increase in the degree of crystallinity. Regarding the mechanical behavior, no significant differences were detected following the addition of the inorganic phases to the polymeric matrix, although a small reduction in the ultimate tensile strength (~14%) and Young's modulus (~5%) in PEEK/HA was observed in comparison to pure PEEK. Moreover, in vitro bioactivity of 3D printed samples was evaluated via a simulated body fluid immersion test for up to 28 days; the formation of apatite was observed on the surfaces of sample surfaces containing HA, SrHA and ZnHA. These results indicate the potential to produce bioactive, 3DP PEEK composites for challenging applications such as in craniofacial bone repair.


Assuntos
Durapatita , Engenharia Tecidual , Benzofenonas , Materiais Biocompatíveis , Humanos , Cetonas , Polietilenoglicóis , Polímeros , Impressão Tridimensional
5.
J Coll Physicians Surg Pak ; 26(6 Suppl): S63-4, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27376227

RESUMO

Inflammatory pseudotumor is a solid fibro-inflammatory tumor that clinically mimics a neoplastic lesion. Inflammatory pseudotumor is usually found in the orbits and lungs, but rarely in the sinonasal area. Presence of pseudotumor in nasal cavity is even scarce and there are only a few reports to date. We present a case of pseudotumor involving the nasal tip area in an adult female mimicking as a slowly enlarging mass.


Assuntos
Granuloma de Células Plasmáticas/diagnóstico , Granuloma de Células Plasmáticas/cirurgia , Cavidade Nasal , Doenças Nasais/diagnóstico , Doenças Nasais/cirurgia , Neoplasias Nasais/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Epistaxe/etiologia , Feminino , Granuloma de Células Plasmáticas/patologia , Humanos , Pessoa de Meia-Idade , Cavidade Nasal/cirurgia , Obstrução Nasal/etiologia , Doenças Nasais/patologia , Neoplasias Nasais/patologia , Neoplasias Nasais/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
6.
Mater Sci Eng C Mater Biol Appl ; 66: 156-163, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27207049

RESUMO

Chitosan's poor solubility especially in organic solvents limits its use with other organo-soluble polymers; however such combinations are highly required to tailor their properties for specific biomedical applications. This paper describes the development of a new synthetic methodology for the synthesis of organo-soluble chitosan derivatives. These derivatives were synthesized from chitosan (CS), triethyl orthoformate and barbituric or thiobarbituric acid in the presence of 2-butannol. The chemical interactions and new functional motifs in the synthesized CS derivatives were evaluated by FTIR, DSC/TGA, UV/VIS, XRD and (1)H NMR spectroscopy. A cytotoxicity investigation for these materials was performed by cell culture method using VERO cell line and all the synthesized derivatives were found to be non-toxic. The solubility analysis showed that these derivatives were readily soluble in organic solvents including DMSO and DMF. Their potential to use with organo-soluble commercially available polymers was exploited by electrospinning; the synthesized derivatives in combination with polycaprolactone delivered nanofibrous membranes.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Tiobarbitúricos/química , Animais , Materiais Biocompatíveis/farmacologia , Butanóis/química , Varredura Diferencial de Calorimetria , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Dimetil Sulfóxido/química , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Células Vero
7.
Mater Sci Eng C Mater Biol Appl ; 56: 104-13, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26249571

RESUMO

Development of biodegradable composites having the ability to suppress or eliminate the pathogenic micro-biota or modulate the inflammatory response has attracted great interest in order to limit/repair periodontal tissue destruction. The present report includes the development of non-steroidal anti-inflammatory drug encapsulated novel biodegradable chitosan (CS)/poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) electro-spun (e-spun) composite nanofibrous mats and films and study of the effect of heat treatment on fibers and films morphology. It also describes comparative in-vitro drug release profiles from heat treated and control (non-heat treated) nanofibrous mats and films containing varying concentrations of piroxicam (PX). Electrospinning was used to obtain drug loaded ultrafine fibrous mats. The physical/chemical interactions were evaluated by Fourier Transform Infrared (FT-IR) spectroscopy. The morphology, structure and pore size of the materials were investigated by scanning electron microscopy (SEM). The thermal behavior of the materials was investigated by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Control (not heat treated) and heat treated e-spun fibers mats and films were tested for in vitro drug release studies at physiological pH7.4 and initially, as per requirement burst release patterns were observed from both fibers and films and later sustained release profiles were noted. In vitro cytocompatibility was performed using VERO cell line of epithelial cells and all the synthesized materials were found to be non-cytotoxic. The current observations suggested that these materials are potential candidates for periodontal regeneration.


Assuntos
Plásticos Biodegradáveis/química , Nanocompostos/química , Periodonto/efeitos dos fármacos , Piroxicam/química , Regeneração/efeitos dos fármacos , Alicerces Teciduais/química , Animais , Linhagem Celular , Quitosana/química , Chlorocebus aethiops , Durapatita/química , Células Epiteliais/efeitos dos fármacos , Microscopia Eletrônica de Varredura/métodos , Nanofibras/química , Álcool de Polivinil/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Engenharia Tecidual/métodos , Células Vero
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