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1.
Int J Biol Macromol ; 171: 514-526, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33428954

RESUMO

The Alginate-Neusilin US2 micro-composite (MC) beads were fabricated and optimized for oral delivery of hesperidin (HES). A 32 full factorial design encompassing independent variables (factors) such as the concentration of sodium alginate (X1), and Neusilin US2 (X2) and dependant variables (response) such as particle size (Y1), entrapment efficiency (Y2), and swelling degree (Y3). Nine batches were prepared by formulation design employing statistical software JMP 13.2.1. The multiple regression analysis (MLRA) was carried to explore the influence of factor over responses. Further, a prediction profiler was used to trace the optimum concentration of factors based on desirable responses. The optimized beads (OF) were characterized for their morphology and size by motic microscopy and scanning electron microscopy. In vitro release, kinetic studies were performed in simulated gastric and intestinal fluids. In vivo pharmacokinetic studies revealed better absorption of HES from optimized beads (OF) compared to HES suspension which could be due to the prevention of acidic degradation of HES in the stomach. The estimated shelf life of OF formulation was found to be 3.86 years suggested better stability after fabrication. In a nutshell, the developed micro-composite beads of HES could be a better alternative for promising oral sustained delivery of HES.


Assuntos
Alginatos/química , Compostos de Alumínio/química , Portadores de Fármacos/química , Suco Gástrico/metabolismo , Hesperidina/administração & dosagem , Compostos de Magnésio/química , Silicatos/química , Administração Oral , Alginatos/administração & dosagem , Alginatos/farmacocinética , Compostos de Alumínio/administração & dosagem , Compostos de Alumínio/farmacocinética , Animais , Líquidos Corporais/metabolismo , Técnicas de Química Analítica , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Hesperidina/farmacocinética , Intestinos , Cinética , Compostos de Magnésio/administração & dosagem , Compostos de Magnésio/farmacocinética , Masculino , Microscopia Eletrônica de Varredura , Microesferas , Tamanho da Partícula , Ratos Wistar , Silicatos/administração & dosagem , Silicatos/farmacocinética
2.
Biotechnol Appl Biochem ; 68(4): 789-800, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32701174

RESUMO

In this study, a novel pH-sensitive hydrogel beads that is based on gelatin/sodium alginate/chitosan (GEL/SA/CS) loaded with propolis ethanolic extracts (PE) were synthesized. The swelling behavior of GEL/SA/CS hydrogel beads was studied in different pH solutions and compared with unloaded CS (GEL/SA) hydrogel beads. The in vitro release studies have been revealed using four different pH (1.3, 5.0, 6.0, and 6.8), a saliva environment (pH 6.8), a simulated gastric fluid (SGF) (pH 1.3), and a simulated intestinal fluid (SIF) (pH 6.8) to simulate the physiological conditions in gastrointestinal (GI) tract. Propolis-loaded hydrogel beads were found to be stable at pH 1.3, 5.0, 6.0, simulated saliva, SGF, and SIF mediums, whereas the beads lose their stability at pH 6.8 buffer solution. Tested microorganisms displayed greater sensitivity to PE-loaded hydrogel beads compared with pure propolis. Contrary to antimicrobial activity results, antibiofilm activity results of PE-loaded GEL/SA and GEL/SA/CS hydrogel beads were found at low levels. According to the obtained results, the propolis-loaded GEL/SA/CS hydrogel beads synthesized within this study can be used in the treatment of GI tract diseases such as oral mucositis, gastric ulcer, ulcerative colitis, and GI cancer, as controlled releasing carriers of propolis.


Assuntos
Anti-Infecciosos , Bactérias/crescimento & desenvolvimento , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Misturas Complexas , Hidrogéis , Própole , Compostos de Alumínio/química , Compostos de Alumínio/farmacocinética , Compostos de Alumínio/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacocinética , Anti-Infecciosos/farmacologia , Quitosana/química , Quitosana/farmacocinética , Quitosana/farmacologia , Misturas Complexas/química , Misturas Complexas/farmacocinética , Misturas Complexas/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Gelatina/química , Gelatina/farmacocinética , Gelatina/farmacologia , Hidrogéis/química , Hidrogéis/farmacocinética , Hidrogéis/farmacologia , Própole/química , Própole/farmacocinética , Própole/farmacologia , Compostos de Sódio/química , Compostos de Sódio/farmacocinética , Compostos de Sódio/farmacologia
3.
Neurotoxicology ; 83: 179-185, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32605715

RESUMO

The fractional uptake of ingested aluminium and aluminium compounds (aluminium citrate, aluminium nitrate, aluminium chloride, aluminium sulphate, aluminium hydroxide, aluminium oxide, aluminium metal, powdered aluminium pot electrolyte, acidic sodium aluminium phosphate (SALP), basic sodium aluminium phosphate (Kasal), sodium aluminium silicate and FD&C red 40 aluminium lake) from the gastro-intestinal tract of adult female rats was measured. This was determined by comparing retained body burden of 26Al at seven days post-admistration of an i.v. injection of 26Al-labelled aluminium citrate with that retained following the gastric admistration of 26Al-labelled test compounds as either solutions or suspended solid. The calculated percentage uptake of 26Al for all the aluminium solutions was similar: aluminium citrate 0.08%, aluminium chloride 0.05%, aluminium nitrate 0.05% and aluminium sulphate 0.21%. The uptake of 26Al administered as insoluble particulates was lower: 0.03% for aluminium hydroxide; 0.02% for aluminium oxide; 0.04% for powdered pot electrolyte; 0.12% for sodium aluminium silicate; and 0.09% for FD&C red 40 aluminium lake. For aluminium metal, SALP and Kasal the amount of 26Al present in the rats was insufficient to determine uptake and was less than 0.03%. The results produced for aluminium citrate, aluminium hydroxide and aluminium sulphate are close to those published for man.


Assuntos
Compostos de Alumínio/farmacocinética , Alumínio/farmacocinética , Absorção Gastrointestinal , Administração Oral , Alumínio/administração & dosagem , Alumínio/toxicidade , Compostos de Alumínio/administração & dosagem , Compostos de Alumínio/toxicidade , Animais , Disponibilidade Biológica , Carga Corporal (Radioterapia) , Feminino , Modelos Biológicos , Ratos Sprague-Dawley , Medição de Risco , Toxicocinética
4.
Daru ; 28(1): 191-208, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32034683

RESUMO

AIM: Canagliflozin (CFZ), a novel SGLT II antagonist, exhibits erratic absorption after oral administration. The current study entails development and evaluation of spray dried lipid based formulation (solid SMEDDS) for enhancing oral bioavailability and anti-diabetic activity of CFZ. METHODS: Solid SMEDDS developed through spray drying containing Neusilin US2 as an adsorbent. The formed solid SMEDDS were characterized for physicochemical and solid state attributes. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were used to confirm the spherical morphology. In vitro dissolution, ex vivo permeability and in vivo pharmacokinetic studies were conducted to determine the release rate, permeation rate and absorption profile of CFZ, respectively. Pharmacodynamic studies were done as per standard protocols. RESULTS: The optimized solid SMEDDS exhibited acceptable practical yield and flow properties and is vouched with enhanced amorphization, nanoparticulate distribution and acceptable drug content. The spherical morphology of solid SMEDDS and reconstituted SMEDDS were confirmed in SEM and TEM, respectively. In vitro dissolution studies revealed multi-fold release behavior in CFZ in various dissolution media, whereas, remarkable permeability was observed in jejunum segment of rat intestine. Pharmacokinetic studies of CFZ in solid SMEDDS demonstrated 2.53 and 1.43 fold enhancement in Cmax and 2.73 and 1.98 fold in AUC 0-24h, as compared to pure API and marketed formulation, respectively. Pharmacological evaluation of solid SMEDDS revealed enhanced anti-diabetic activity of CFZ through predominant SGLT II inhibition in rats, as evident from evaluation of biochemical levels, urinary glucose excretion studies and SGLT II expression analysis. CONCLUSION: The current work describes significant improvement biopharmaceutical properties of CFZ in solid SMEDD formulation. Graphical abstract Graphical Abstract: Enhanced oral bioavailability and anti-diabetic activity of canagliflozin through a spray dried lipid based oral delivery: a novel paradigm.


Assuntos
Canagliflozina/administração & dosagem , Diabetes Mellitus Experimental/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Hipoglicemiantes/administração & dosagem , Administração Oral , Compostos de Alumínio/administração & dosagem , Compostos de Alumínio/química , Compostos de Alumínio/farmacocinética , Animais , Disponibilidade Biológica , Canagliflozina/sangue , Canagliflozina/química , Canagliflozina/farmacocinética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/urina , Liberação Controlada de Fármacos , Glicosúria , Hipoglicemiantes/sangue , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Absorção Intestinal , Rim/efeitos dos fármacos , Rim/metabolismo , Lipídeos/administração & dosagem , Lipídeos/química , Lipídeos/farmacocinética , Compostos de Magnésio/administração & dosagem , Compostos de Magnésio/química , Compostos de Magnésio/farmacocinética , Excipientes Farmacêuticos/administração & dosagem , Excipientes Farmacêuticos/química , Excipientes Farmacêuticos/farmacocinética , Ratos Wistar , Silicatos/administração & dosagem , Silicatos/química , Silicatos/farmacocinética , Transportador 2 de Glucose-Sódio/metabolismo , Secagem por Atomização
5.
Skin Pharmacol Physiol ; 33(1): 1-8, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31553995

RESUMO

BACKGROUND AND OBJECTIVES: Adverse health effects such as neurotoxic and carcinogenic effects through aluminum from cosmetic products have been repeatedly discussed. The dermal uptake and impact on the systemic aluminum load is still poorly understood. Therefore, we investigated the effect of daily antiperspirant use on the systemic aluminum load under real-life conditions. METHODS: 21 healthy subjects meeting certain selection criteria to ensure a low systemic aluminum background load were asked to use a commercial aluminum-containing antiperspirant for 14 days. A questionnaire enquired about shaving habits and other sources of aluminum. Aluminum levels were measured before and after the exposure in 24-h urine and plasma using atomic absorption spectroscopy. Urine samples (n = 6) with <700 mg/day creatinine excretion or more than 30% difference in 24-h creatinine excretion were excluded from further analysis. RESULTS: No significant increase in plasma aluminum concentration or total excreted aluminum per day before and after exposure was measurable. No sample exceeded the reference values of the general population (maximum: 9.42 µg/g creatinine and 2.1 µg/L plasma). Shaving habits did not have a significant influence on the systemic aluminum load. Also, no correlation between the total amount of antiperspirant applied and the systemic aluminum level could be demonstrated. CONCLUSIONS: No measurable contribution to the overall systemically available aluminum load due to daily use of an antiperspirant for 14 days could be shown, but real-life data concerning long-term use or higher concentrations are still lacking. Considering toxicological occupational exposure data, adverse neurotoxic changes are unlikely in the case of urinary excretion of <50 µg aluminum/g creatinine (= no observed adverse effect level), even following long-term exposure.


Assuntos
Compostos de Alumínio/farmacocinética , Alumínio/sangue , Alumínio/urina , Antiperspirantes/farmacocinética , Administração Cutânea , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
6.
Arch Toxicol ; 93(10): 2787-2796, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31522239

RESUMO

Aluminium (Al) toxicokinetics after intramuscular (IM) injection of Al-adjuvanted vaccines is unknown. Since animal data are required for modeling and extrapolation, a rat study was conducted measuring Al in plasma and tissues after IM injection of either plain Al-hydroxide (pAH) or Al-phosphate (pAP) adjuvant (Al dose 1.25 mg), single human doses of three Al-adjuvanted vaccines (V1, V2, and V3; Al doses 0.5-0.82 mg), or vehicle (saline). A significant increase in Al plasma levels compared to controls was observed after pAP (AUC(0-80 d), mean ± SD: 2424 ± 496 vs. 1744 ± 508 µg/L*d). Percentage of Al dose released from injected muscle until day 80 was higher after pAP (66.9%) and AP-adjuvanted V3 (85.5%) than after pAH and AH-adjuvanted V1 (0 and 22.3%, resp.). Estimated absolute Al release was highest for pAP (836.8 µg per rat). Al concentration in humerus bone was increased in all groups, again strongest in the pAP group [3.35 ± 0.39 vs. 0.05 ± 0.06 µg/g wet weight (ww)]. Extrapolated amounts in whole skeleton corresponded to 5-12% of the released Al dose. Very low brain Al concentrations were observed in all groups (adjuvant group means 0.14-0.29 µg/g ww; control 0.13 ± 0.04 µg/g ww). The results demonstrate systemically available Al from marketed vaccines in rats being mainly detectable in bone. Al release appears to be faster from AP- than AH-adjuvants. Dose scaling to human adults suggests that increase of Al in plasma and tissues after single vaccinations will be indistinguishable from baseline levels.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Compostos de Alumínio/administração & dosagem , Hidróxido de Alumínio/administração & dosagem , Fosfatos/administração & dosagem , Vacinas/administração & dosagem , Adjuvantes Imunológicos/farmacocinética , Compostos de Alumínio/farmacocinética , Hidróxido de Alumínio/farmacocinética , Animais , Área Sob a Curva , Humanos , Injeções Intramusculares , Masculino , Fosfatos/farmacocinética , Ratos , Ratos Wistar , Distribuição Tecidual , Vacinas/farmacocinética
7.
Toxicol Lett ; 314: 1-9, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295537

RESUMO

Oral administration is the preferred route of exposure for non-volatile chemicals with potential environmental exposures. For metal salts, systemic doses in such toxicity testing are often low due to limited oral bioavailability. Issues arising from the low bioavailability for toxicity testing and risk characterization are illustrated using aluminum (Al) salts as example. Al-cations have an oral bioavailability of below 1% and applicable doses are limited resulting in low systemic doses. Consequently, the low systemic doses are insufficient to induce clear adverse effects that may serve as points of departure for risk characterization.


Assuntos
Compostos de Alumínio/administração & dosagem , Compostos de Alumínio/toxicidade , Testes de Toxicidade/métodos , Administração Oral , Compostos de Alumínio/farmacocinética , Animais , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Humanos , Reprodutibilidade dos Testes , Medição de Risco , Toxicocinética
8.
J Biomed Mater Res B Appl Biomater ; 107(6): 2195-2201, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30637978

RESUMO

To evaluate the properties of experimental mineral trioxide aggregate (MTA) resin-modified materials for root-end filling procedures, varying their compositions regarding the addition of hydroxiapatite (HA) or dicalcium phosphate dihydrate, with or without chlorhexidine digluconate. White MTA (Angelus, Londrina, Brazil) was used as a reference material. Degree of conversion (DC) was evaluated by Fourier transformed infrared (FTIr) spectroscopy (n = 5). Flowability (n = 3) and radiopacity (n = 3) were evaluated following ISO 6876:2001 methods. For splitting tensile strength analysis, cylindrical samples (n = 10) were subjected to compressive load using a universal testing machine (Instron Corporation, Norwood, MA). Water sorption and solubility tests were performed according to ISO 4049:2009 methods. Calcium ion release and pH analysis (n = 10) were evaluated using a pH meter (Orion, Watsonville, CA). Cytotoxicity (n = 8) of materials extracts was evaluated as cell viability percentage. Statistical analysis was performed using Kolmogorov-Smirnov for normal distribution and data was subjected to one-way ANOVA and Tukey test (α = 0.05). Addition of chlorhexidine digluconate reduced DC mean values for experimental materials (<50%). White MTA demonstrated lower flowability (5.3 mm) and higher radiopacity (9.8 mm Al), splitting tensile strength (9.1 MPa), solubility (8.2 µg/mm3 ), calcium ion release (~26.5 ppm), cytotoxicity (55.2%), and pH mean values (10.8), when compared to experimental materials. All groups demonstrated a decrease in calcium release (<85%) and pH (<13%). Formulation containing HA demonstrated similar pH values after 28 days when compared to white MTA. Evaluated experimental resin-modified MTA based materials without chlorhexidine digluconate showed satisfactory results for all physico-chemical properties tested and cytotoxicity. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2195-2201, 2019.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Clorexidina/análogos & derivados , Fibroblastos/metabolismo , Teste de Materiais , Óxidos , Materiais Restauradores do Canal Radicular , Silicatos , Compostos de Alumínio/química , Compostos de Alumínio/farmacocinética , Compostos de Alumínio/farmacologia , Animais , Compostos de Cálcio/química , Compostos de Cálcio/farmacocinética , Compostos de Cálcio/farmacologia , Linhagem Celular , Clorexidina/química , Clorexidina/farmacocinética , Clorexidina/farmacologia , Combinação de Medicamentos , Camundongos , Óxidos/química , Óxidos/farmacocinética , Óxidos/farmacologia , Materiais Restauradores do Canal Radicular/química , Materiais Restauradores do Canal Radicular/farmacocinética , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/química , Silicatos/farmacocinética , Silicatos/farmacologia
9.
Nat Protoc ; 13(10): 2330-2347, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30250289

RESUMO

Positron emission tomography (PET) is a quickly expanding, non-invasive molecular imaging technology, and there is high demand for new specific imaging probes. Herein, we present a generic protocol for direct radiolabeling of heat-sensitive biomolecules with the positron-emitting radioisotope fluorine-18 (18F) using the aluminum fluoride restrained complexing agent (Al18F-RESCA) method. The Al18F-RESCA method combines the chemical advantages of a chelator-based radiolabeling method with the unique physical properties of the radionuclide of choice, fluorine-18. Proteins of interest can be conjugated to RESCA via amine coupling using (±)-H3RESCA-TFP, followed by purification using size-exclusion chromatography (SEC). Next, RESCA-derivatized biomolecules can be labeled in one step, at room temperature (~20 °C) in an aqueous medium with aluminum fluoride (Al18F). Al18F-labeled proteins can be obtained with moderate (12-17 GBq/µmol) to good (80-85 GBq/µmol) apparent molar activity, depending on the starting activity of 18F-. In addition, satisfactory radiochemical yields (35-55%, non-decay corrected) and high radiochemical purity (>98%, using gel filtration or solid-phase purification) are obtained. The mild radiolabeling procedure takes 0.5 h to complete and can be used for direct labeling of vector molecules such as peptides, protein scaffolds, and engineered antibody fragments.


Assuntos
Compostos de Alumínio/química , Complexos de Coordenação/química , Fluoretos/química , Radioisótopos de Flúor/química , Peptídeos/química , Tomografia por Emissão de Pósitrons/métodos , Proteínas/química , Compostos de Alumínio/farmacocinética , Animais , Complexos de Coordenação/farmacocinética , Fluoretos/farmacocinética , Radioisótopos de Flúor/farmacocinética , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacocinética , Temperatura Alta , Camundongos , Modelos Moleculares , Peptídeos/farmacocinética , Proteínas/farmacocinética , Ratos , Anticorpos de Domínio Único/química , Distribuição Tecidual
10.
J Inorg Biochem ; 181: 87-95, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29307441

RESUMO

We reviewed the three toxicokinetic reference studies commonly used to suggest that aluminum (Al)-based adjuvants are innocuous. A single experimental study was carried out using isotopic 26Al (Flarend et al., Vaccine, 1997). This study used aluminum salts resembling those used in vaccines but ignored adjuvant uptake by cells that was not fully documented at the time. It was conducted over a short period of time (28days) and used only two rabbits per adjuvant. At the endpoint, Al elimination in the urine accounted for 6% for Al hydroxide and 22% for Al phosphate, both results being incompatible with rapid elimination of vaccine-derived Al in urine. Two theoretical studies have evaluated the potential risk of vaccine Al in infants, by reference to an oral "minimal risk level" (MRL) extrapolated from animal studies. Keith et al. (Vaccine, 2002) used a high MRL (2mg/kg/d), an erroneous model of 100% immediate absorption of vaccine Al, and did not consider renal and blood-brain barrier immaturity. Mitkus et al. (Vaccine, 2011) only considered solubilized Al, with erroneous calculations of absorption duration. Systemic Al particle diffusion and neuro-inflammatory potential were omitted. The MRL they used was both inappropriate (oral Al vs. injected adjuvant) and still too high (1mg/kg/d) regarding recent animal studies. Both paucity and serious weaknesses of reference studies strongly suggest that novel experimental studies of Al adjuvants toxicokinetics should be performed on the long-term, including both neonatal and adult exposures, to ensure their safety and restore population confidence in Al-containing vaccines.


Assuntos
Adjuvantes Imunológicos/efeitos adversos , Compostos de Alumínio/efeitos adversos , Alumínio/toxicidade , Complexos de Coordenação/toxicidade , Vacinas/efeitos adversos , Absorção Fisiológica , Adjuvantes Imunológicos/sangue , Adjuvantes Imunológicos/metabolismo , Adjuvantes Imunológicos/farmacocinética , Adolescente , Adulto , Fatores Etários , Alumínio/sangue , Alumínio/metabolismo , Alumínio/urina , Compostos de Alumínio/sangue , Compostos de Alumínio/metabolismo , Compostos de Alumínio/farmacocinética , Animais , Criança , Complexos de Coordenação/sangue , Complexos de Coordenação/metabolismo , Complexos de Coordenação/urina , Humanos , Lactente , Eliminação Renal , Testes de Toxicidade , Toxicocinética
11.
Toxicol Lett ; 283: 77-85, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29180288

RESUMO

Many employees in the aluminum industry are exposed to a range of aluminum compounds by inhalation, and the presence of ultrafine particles in the workplace has become a concern to occupational health professionals. Some metal salts and metal oxides have been shown to enter the brain through the olfactory route, bypassing the blood-brain barrier, but few studies have examined whether aluminum compounds also use this pathway. In this context, we sought to determine whether aluminum was found in rat olfactory bulbs and whether its transfer depended on physicochemical characteristics such as solubility and granulometry. Aluminum salts (chloride and fluoride) and various nanometric aluminum oxides (13nm, 20nm and 40-50nm) were administered to rats by intranasal instillation through one nostril (10µg Al/30µL for 10days). Olfactory bulbs (ipsilateral and contralateral relative to instilled nostril) were harvested and the aluminum content was determined by graphite furnace atomic absorption spectrometry after tissue mineralization. Some transfer of aluminum salts to the central nervous system via the olfactory route was observed, with the more soluble aluminum chloride being transferred at higher levels than aluminum fluoride. No cerebral translocation of any of the aluminas studied was detected.


Assuntos
Compostos de Alumínio/metabolismo , Compostos de Alumínio/toxicidade , Encéfalo/metabolismo , Condutos Olfatórios/metabolismo , Administração Intranasal , Algoritmos , Cloreto de Alumínio , Compostos de Alumínio/farmacocinética , Animais , Cloretos/metabolismo , Cloretos/farmacocinética , Cloretos/toxicidade , Fluoretos/metabolismo , Fluoretos/farmacocinética , Fluoretos/toxicidade , Masculino , Mucosa Nasal/patologia , Bulbo Olfatório/metabolismo , Ratos , Ratos Sprague-Dawley , Espectrofotometria Atômica
12.
Mol Pharm ; 14(12): 4353-4361, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-29028357

RESUMO

The folate receptor (FR) has been established as a promising target for imaging and therapy of cancer (FR-α), inflammation, and autoimmune diseases (FR-ß). Several folate based PET radiotracers have been reported in the literature, but an 18F-labeled folate-PET imaging agent with optimal properties for clinical translation is still lacking. In the present study, we report the design and preclinical evaluation of folate-PEG12-NOTA-Al18F (1), a new folate-PET agent with improved potential for clinical applications. Radiochemical synthesis of 1 was achieved via a one-pot labeling process by heating folate-PEG12-NOTA in the presence of in situ prepared Al18F for 15 min at 105 °C, followed by HPLC purification. Specific binding of 1 to FR was evaluated on homogenates of KB (FR-positive) and A549 (FR-deficient) tumor xenografts in the presence and absence of excess folate. In vivo tumor imaging with folate-PEG12-NOTA-Al18F was compared to imaging with 99mTc-EC20 using nu/nu mice bearing either KB or A549 tumor xenografts. Specific accumulation of 1 in tumor and other tissues was assessed by high-resolution micro-PET and ex vivo biodistribution in the presence and absence of excess folate. Radiosynthesis of 1 was accomplished within ∼35 min, affording pure radiotracer 1 in 8.4 ± 1.3% (decay corrected) radiochemical yield with ∼100% radiochemical purity after HPLC purification and a specific activity of 35.8 ± 15.3 GBq/mmol. Further in vitro and in vivo examination of 1 demonstrated highly specific FR-mediated uptake in FR+ tumor, with Kd of ∼0.4 nM (KB), and reduced accumulation in liver. Given its facile preparation and improved properties, the new radiotracer, folate-PEG12-NOTA-Al18F (1), constitutes a promising tool for identification and classification of patients with FR overexpressing cancers.


Assuntos
Receptores de Folato com Âncoras de GPI/metabolismo , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacocinética , Células A549 , Compostos de Alumínio/química , Compostos de Alumínio/farmacocinética , Animais , Avaliação Pré-Clínica de Medicamentos , Feminino , Fluoretos/química , Fluoretos/farmacocinética , Radioisótopos de Flúor/química , Radioisótopos de Flúor/farmacocinética , Ácido Fólico/análogos & derivados , Ácido Fólico/química , Ácido Fólico/farmacocinética , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacocinética , Compostos Heterocíclicos com 1 Anel , Humanos , Marcação por Isótopo/métodos , Células KB , Camundongos , Camundongos Nus , Neoplasias/patologia , Compostos de Organotecnécio , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Compostos Radiofarmacêuticos/química , Distribuição Tecidual , Microtomografia por Raio-X/métodos , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Appl Toxicol ; 37(12): 1408-1419, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28840595

RESUMO

The tissue distribution and toxicity of nanoparticles (NPs) depend on their physical and chemical properties both in the manufactured condition and within the biological system. We characterized three types of commercially available aluminum-based NPs (Al-NPs), two rod-type aluminum oxide NPs (Al2 O3 , AlONPs), with different aspect ratios (short [S]- and long [L]-AlONPs), and spherical aluminum cerium oxide NPs (AlCeO3 , AlCeONPs). The surface area was in order of the S-AlONPs > L-AlONPs > AlCeONPs. Very importantly, we found that AlCeONPs is Al2 O3 -coated CeO2 NPs, but not AlCeO3 NPs, and that the Al level in AlCeONPs is approximately 20% of those in S- and L-AlONPs. All three types of Al-NPs were slightly ionized in gastric fluid and rapidly particlized in the intestinal fluid. There were no significant differences in the body weight gain following 28 days of repeated oral administration of the three different types of Al-NPs. All Al-NPs elevated Al level in the heart, spleen, kidney and blood at 24 hours after the final dose, accompanied by the altered tissue level of redox reaction-related trace elements. Subsequently, in four types of cells derived from the organs which Al-NPs are accumulated, H9C2 (heart), HEK-293 (kidney), splenocytes and RAW264.7 (blood), S-AlONPs showed a very low uptake level and did not exert significant cytotoxicity. Meanwhile, cytotoxicity and uptake level were the most remarkable in cells treated with AlCeONPs. In conclusion, we suggest that the physicochemical properties of NPs should be examined in detail before the release into the market to prevent unexpected adverse health effects.


Assuntos
Compostos de Alumínio , Cério/química , Nanopartículas Metálicas , Administração Oral , Compostos de Alumínio/química , Compostos de Alumínio/farmacocinética , Compostos de Alumínio/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Humanos , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Camundongos Endogâmicos ICR , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Especificidade de Órgãos , Oxirredução , Tamanho da Partícula , Ratos , Propriedades de Superfície , Distribuição Tecidual
14.
Int J Artif Organs ; 40(11): 641-646, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-28708217

RESUMO

INTRODUCTION: The aim of this study was to evaluate and compare the calcium (Ca2+) and hydroxide (OH-) ion release of 4 artificially produced pulp capping materials (MTA, Biodentin, TheraCal LC, Calsimol) used for indirect pulp capping treatment. METHODS: In total, 70 freshly extracted human third molar teeth were used for the study. Cavities of extracted teeth were prepared by round burs. The remaining dentin thickness (1 ± 0.3 mm) tissue was measured by a micrometer and cone beam computerized tomography. Indirect pulp capping was performed in the cavities using Calcimol, MTA, TheraCal LC and Biodentin. The leached Ca2+ were measured using optical emission spectrometry and the release of OH- ions using a pH meter. The measurements were performed after 24 hours, 7 days and 28 days in saline solution. Statistical analysis was performed using 1-way and 2-way analysis of variance (ANOVA) tests (p<0.05). RESULTS: Ca2+ ions were detected in treated saline solution during the experimental period for all materials. All the measurements of Biodentin and Theracal LC levels for Ca2+ ions were higher than those of the other materials (p<0.05). For all materials, Ca2+-ion release increased during the first 7 days followed by a linear decrease during the subsequent study periods. The Biodentine group showed the highest OH- ion rates compared to the other materials in the 24-hour examination period, while the scores gradually decreased during the subsequent measurement periods (p<0.05). CONCLUSIONS: Tricalcium silicate materials such as Biodentine and TheraCal LC used in this study may be preferable for indirect pulp capping because of their stimulation of hard tissue formation and ion-releasing ability.


Assuntos
Cálcio/farmacocinética , Polpa Dentária/metabolismo , Hidróxidos/farmacocinética , Agentes de Capeamento da Polpa Dentária e Pulpectomia/farmacocinética , Compostos de Alumínio/farmacocinética , Compostos de Cálcio/farmacocinética , Hidróxido de Cálcio/farmacocinética , Capeamento da Polpa Dentária , Combinação de Medicamentos , Humanos , Óxidos/farmacocinética , Cimentos de Resina/farmacocinética , Silicatos/farmacocinética , Técnicas de Cultura de Tecidos
15.
Morphologie ; 100(329): 75-84, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26970682

RESUMO

Since World War II, several factors such as an impressive industrial growth, an enhanced environmental bioavailability and intensified food consumption have contributed to a significant amplification of human exposure to aluminum. Aluminum is particularly present in food, beverages, some drugs and airbone dust. In our food, aluminum is superimposed via additives and cooking utensils. Therefore, the tolerable intake of aluminum is exceeded for a significant part of the world population, especially in children who are more vulnerable to toxic effects of pollutants than adults. Faced with this oral aluminum influx, intestinal tract is an essential barrier, especially as 38% of ingested aluminum accumulates at the intestinal mucosa. Although still poorly documented to date, the impact of oral exposure to aluminum in conditions relevant to real human exposure appears to be deleterious for gut homeostasis. Aluminum ingestion affects the regulation of the permeability, the microflora and the immune function of intestine. Nowadays, several arguments are consistent with an involvement of aluminum as an environmental risk factor for inflammatory bowel diseases.


Assuntos
Compostos de Alumínio/farmacocinética , Compostos de Alumínio/toxicidade , Doença de Crohn/induzido quimicamente , Exposição Ambiental/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Doenças Inflamatórias Intestinais/induzido quimicamente , Mucosa Intestinal/efeitos dos fármacos , Adulto , Animais , Bebidas/normas , Disponibilidade Biológica , Criança , Utensílios de Alimentação e Culinária , Doença de Crohn/veterinária , Poeira , Ingestão de Alimentos , Poluentes Ambientais/toxicidade , Alimentos/normas , Estudo de Associação Genômica Ampla , Homeostase/efeitos dos fármacos , Cavalos , Humanos , Incidência , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/fisiopatologia , Mucosa Intestinal/química , Mucosa Intestinal/patologia , Mucosa Intestinal/fisiopatologia , Fatores de Risco
16.
Morphologie ; 100(329): 65-74, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26997127

RESUMO

The human population is exposed to aluminium (Al) from diet, antacids and vaccine adjuvants, but frequent application of Al-based salts to the underarm as antiperspirant adds a high additional exposure directly to the local area of the human breast. Coincidentally the upper outer quadrant of the breast is where there is also a disproportionately high incidence of breast cysts and breast cancer. Al has been measured in human breast tissues/fluids at higher levels than in blood, and experimental evidence suggests that at physiologically relevant concentrations, Al can adversely impact on human breast epithelial cell biology. Gross cystic breast disease is the most common benign disorder of the breast and evidence is presented that Al may be a causative factor in formation of breast cysts. Evidence is also reviewed that Al can enable the development of multiple hallmarks associated with cancer in breast cells, in particular that it can cause genomic instability and inappropriate proliferation in human breast epithelial cells, and can increase migration and invasion of human breast cancer cells. In addition, Al is a metalloestrogen and oestrogen is a risk factor for breast cancer known to influence multiple hallmarks. The microenvironment is established as another determinant of breast cancer development and Al has been shown to cause adverse alterations to the breast microenvironment. If current usage patterns of Al-based antiperspirant salts contribute to causation of breast cysts and breast cancer, then reduction in exposure would offer a strategy for prevention, and regulatory review is now justified.


Assuntos
Compostos de Alumínio/toxicidade , Alumínio/toxicidade , Antiperspirantes/efeitos adversos , Mama/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Estrogênios/análogos & derivados , Alumínio/análise , Alumínio/farmacocinética , Compostos de Alumínio/farmacocinética , Antiperspirantes/química , Axila , Disponibilidade Biológica , Mama/química , Mama/citologia , Cisto Mamário/induzido quimicamente , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/genética , Feminino , Doença da Mama Fibrocística/induzido quimicamente , Instabilidade Genômica/efeitos dos fármacos , Humanos , Fatores de Risco , Absorção Cutânea/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
17.
Morphologie ; 100(329): 51-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26922890

RESUMO

We are living in the 'aluminium age'. Human exposure to aluminium is inevitable and, perhaps, inestimable. Aluminium's free metal cation, Alaq(3+), is highly biologically reactive and biologically available aluminium is non-essential and essentially toxic. Biologically reactive aluminium is present throughout the human body and while, rarely, it can be acutely toxic, much less is understood about chronic aluminium intoxication. Herein the question is asked as to how to diagnose aluminium toxicity in an individual. While there are as yet, no unequivocal answers to this problem, there are procedures to follow to ascertain the nature of human exposure to aluminium. It is also important to recognise critical factors in exposure regimes and specifically that not all forms of aluminium are toxicologically equivalent and not all routes of exposure are equivalent in their delivery of aluminium to target sites. To ascertain if Alzheimer's disease is a symptom of chronic aluminium intoxication over decades or breast cancer is aggravated by the topical application of an aluminium salt or if autism could result from an immune cascade initiated by an aluminium adjuvant requires that each of these is considered independently and in the light of the most up to date scientific evidence. The aluminium age has taught us that there are no inevitabilities where chronic aluminium toxicity is concerned though there are clear possibilities and these require proving or discounting but not simply ignored.


Assuntos
Adjuvantes Imunológicos/efeitos adversos , Compostos de Alumínio/farmacocinética , Compostos de Alumínio/toxicidade , Doença de Alzheimer/induzido quimicamente , Neoplasias da Mama/induzido quimicamente , Exposição Ambiental/efeitos adversos , Neurônios/efeitos dos fármacos , Compostos de Alumínio/efeitos adversos , Antiperspirantes/efeitos adversos , Antiperspirantes/química , Disponibilidade Biológica , Encéfalo/efeitos dos fármacos , Humanos , Fatores de Risco , Vacinas/efeitos adversos
18.
J Endod ; 42(4): 632-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26898564

RESUMO

INTRODUCTION: The treatments for which mineral trioxide aggregate (MTA)-based materials can be used in dentistry are expanding. Smaller particle size and easier handling properties have allowed the advent of tricalcium silicate sealers including EndoSequence BC Sealer (Brasseler USA, Savannah, GA), QuickSet2 (Avalon Biomed, Bradenton, FL), NeoMTA Plus (Avalon Biomed), and MTA Fillapex (Angelus, Londrina, Brazil). The objective of this study was to measure the tubule penetration with these sealers using continuous wave (CW) and single-cone (SC) obturation techniques. METHODS: Eighty single-rooted teeth were randomly divided into 8 groups of 10 and obturated with 1 of the previously mentioned sealers mixed with trace amounts of rhodamine using either the CW or SC technique. Teeth were sectioned at 1 mm and 5 mm from the apex and examined under a confocal laser microscope. The percentage of sealer penetration and the maximum sealer penetration were measured. RESULTS: The tricalcium silicate sealers penetrated tubules as deep as 2000 µm (2 mm). The percentage of sealer penetration was much higher 5 mm from the apex, with many specimens having 100% penetration for both SC and warm vertical techniques. MTA Fillapex, a resin-based sealer with less than 20% MTA particles, had significantly greater tubule penetration with a warm vertical technique versus the SC technique at the 1-mm level. CONCLUSIONS: Within the limitations of this study, the CW and SC techniques produced similar tubule penetration at both the 1-mm and the 5-mm level with the tricalcium silicate sealers BC Sealer, QuickSet2, and NeoMTA Plus.


Assuntos
Compostos de Alumínio/farmacocinética , Compostos de Cálcio/farmacocinética , Dentina/metabolismo , Óxidos/farmacocinética , Materiais Restauradores do Canal Radicular/farmacocinética , Silicatos/farmacocinética , Cimento de Óxido de Zinco e Eugenol/farmacocinética , Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Dentina/anatomia & histologia , Dentina/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Óxidos/farmacologia , Distribuição Aleatória , Materiais Restauradores do Canal Radicular/farmacologia , Irrigantes do Canal Radicular/farmacocinética , Irrigantes do Canal Radicular/farmacologia , Obturação do Canal Radicular/métodos , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Silicatos/farmacologia , Dente/metabolismo , Ápice Dentário/anatomia & histologia , Ápice Dentário/efeitos dos fármacos , Ápice Dentário/metabolismo , Cimento de Óxido de Zinco e Eugenol/farmacologia
19.
Environ Sci Pollut Res Int ; 22(14): 11001-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25787218

RESUMO

It is suspected that drinking water containing fluoride and aluminum results in negative health effects especially on brain, liver, and kidney. In this investigation, the effect of F, Al, and AlFx complex on chronic kidney disease (CKD) was investigated. Mice were treated either with WHO recommended or slightly higher F and Al levels in drinking water. Treatment solutions contained 0.05-10.0 mg/L of F, 0.08-10.0 mg/L of Al, or 0.07-15 mg/L of AlFx, and the treatment period was 42 weeks. Blood urea level and creatinine levels were investigated as a measure of malfunction of kidneys. Histopathological evaluations of kidney tissues were carried out to assess the extent of damage that F, Al, and AlFx complex could cause. It was demonstrated that the treated drinking water containing F and Al with par with WHO or moderately above the WHO levels or AlFx in low level (0.07-15 mg/L) does not lead to CKD in mice.


Assuntos
Compostos de Alumínio/toxicidade , Alumínio/toxicidade , Fluoretos/toxicidade , Rim/efeitos dos fármacos , Alumínio/farmacocinética , Compostos de Alumínio/farmacocinética , Animais , Creatinina/sangue , Água Potável , Feminino , Fluoretos/farmacocinética , Rim/metabolismo , Camundongos Endogâmicos ICR , Insuficiência Renal Crônica , Ureia/sangue , Purificação da Água
20.
J Appl Toxicol ; 35(5): 543-50, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25219755

RESUMO

The risk of penetrating, traumatic injury occurring in a chemically contaminated environment cannot be discounted. Should a traumatic injury be contaminated with a chemical warfare (CW) agent, it is likely that standard haemostatic treatment options would be complicated by the need to decontaminate the wound milieu. Thus, there is a need to develop haemostatic products that can simultaneously arrest haemorrhage and decontaminate CW agents. The purpose of this study was to evaluate a number of candidate haemostats for efficacy as skin decontaminants against three CW agents (soman, VX and sulphur mustard) using an in vitro diffusion cell containing undamaged pig skin. One haemostatic product (WoundStat™) was shown to be as effective as the standard military decontaminants Fuller's earth and M291 for the decontamination of all three CW agents. The most effective haemostatic agents were powder-based and use fluid absorption as a mechanism of action to sequester CW agent (akin to the decontaminant Fuller's earth). The envisaged use of haemostatic decontaminants would be to decontaminate from within wounds and from damaged skin. Therefore, WoundStat™ should be subject to further evaluation using an in vitro model of damaged skin.


Assuntos
Substâncias para a Guerra Química/toxicidade , Descontaminação/métodos , Hemostáticos/farmacocinética , Ferimentos e Lesões/tratamento farmacológico , Compostos de Alumínio/farmacocinética , Animais , Compostos de Magnésio/farmacocinética , Gás de Mostarda/toxicidade , Compostos Organotiofosforados/toxicidade , Silicatos/farmacocinética , Pele/efeitos dos fármacos , Absorção Cutânea/efeitos dos fármacos , Soman/toxicidade , Suínos , Ferimentos e Lesões/induzido quimicamente , Ferimentos e Lesões/patologia
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