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1.
Antimicrob Agents Chemother ; 67(10): e0042423, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37695304

RESUMO

We have previously reported promising in vivo activity of the first-generation 2-aminopyramidine robenidine analogue NCL195 against Gram-positive bacteria (GPB) when administered via the systemic route. In this study, we examined the efficacy of oral treatment with NCL195 (± low-dose colistin) in comparison to oral moxifloxacin in bioluminescent Staphylococcus aureus and Escherichia coli peritonitis-sepsis models. Four oral doses of 50 mg/kg NCL195, commencing immediately post-infection, were administered at 4 h intervals in the S. aureus peritonitis-sepsis model. We used a combination of four oral doses of 50 mg/kg NCL195 and four intraperitoneal doses of colistin at 0.125 mg/kg, 0.25 mg/kg, or 0.5 mg/kg in the E. coli peritonitis-sepsis model. Subsequently, the dose rates of four intraperitoneal doses of colistin were increased to 0.5 mg/kg, 1 mg/kg, or 2 mg/kg at 4 h intervals to treat a colistin-resistant E. coli infection. In the S. aureus infection model, oral treatment of mice with NCL195 resulted in significantly reduced S. aureus infection loads (P < 0.01) and longer survival times (P < 0.001) than vehicle-only treated mice. In the E. coli infection model, co-administration of NCL195 and graded doses of colistin resulted in a dose-dependent significant reduction in colistin-susceptible (P < 0.01) or colistin-resistant (P < 0.05) E. coli loads compared to treatment with colistin alone at similar concentrations. Our results confirm that NCL195 is a potential candidate for further preclinical development as a specific treatment for multidrug-resistant infections, either as a stand-alone antibiotic for GPB or in combination with sub-inhibitory concentrations of colistin for Gram-negative bacteria.


Assuntos
Bacteriemia , Infecções por Escherichia coli , Peritonite , Sepse , Infecções Estafilocócicas , Camundongos , Animais , Colistina/farmacologia , Colistina/uso terapêutico , Staphylococcus aureus , Escherichia coli , Robenidina/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Escherichia coli/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Peritonite/tratamento farmacológico , Sepse/tratamento farmacológico , Bacteriemia/tratamento farmacológico , Administração Oral , Testes de Sensibilidade Microbiana
2.
BMC Vet Res ; 19(1): 39, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36759841

RESUMO

BACKGROUND: Otitis externa is a commonly diagnosed dermatological disorder in canines. The pathogens primarily involved in canine otitis externa (COE) include Staphylococcus pseudintermedius, Pseudomonas aeruginosa, Proteus mirabilis, and Malassezia pachydermatis. As COE tends to be superficial, medications delivered topically are often effective and practical in managing the condition. As such, there is a wide variety of approved topical products currently available in the market. The efficacy of topical dosage forms can be dependent on various factors such as the pharmacology of active constituents and the physicochemical properties of the formulation, including pH, viscosity, spreadability, and bio-adhesion. Currently, there is a lack of published literature available on the optimal properties of topical COE products. In this study, we compared the physicochemical properties of nine commercially available otic veterinarian products in Australia used clinically to manage COE. RESULTS: Based on our comparative analysis, the pH (6.26 ± 0.04) of an aqueous-based product was similar to a healthy dog's external auditory canal. Products containing polymers exhibited higher viscosity and bio-adhesion. Spreadability was inversely related to viscosity and Osurnia ® a product with high viscosity demonstrated the lowest spreadability. Aqueous-based otic products showed better syringebility whereas oil-based systems required higher force to expel the products. Variability in droplet size was noted. Derm Otic, Baytril Otic, and Aurizon Ear Drops had the lower standard deviation which indicates they would give a more consistent dose. CONCLUSIONS: Findings from this work provide considerations for industry researchers or formulation scientists working in the area of otic dosage formulations.


Assuntos
Fármacos Dermatológicos , Doenças do Cão , Otite Externa , Drogas Veterinárias , Animais , Cães , Austrália , Doenças do Cão/tratamento farmacológico , Otite Externa/tratamento farmacológico , Otite Externa/veterinária , Fármacos Dermatológicos/análise , Fármacos Dermatológicos/química , Drogas Veterinárias/análise , Drogas Veterinárias/química
3.
Int J Mol Sci ; 23(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35806191

RESUMO

Strategies that alter the pH of wounds to improve healing outcomes are an emerging area of interest. Currently, there is limited understanding of the effect of hydrogen (H+) on the functionality of skin cells during proliferation and migration, highlighting the need for research to determine the effect of pH during wound healing. This study aimed to determine the effect of acidification on the metabolic activity and migration of human immortalized keratinocytes (HaCaT) and human foreskin fibroblasts (HFF). In vitro models were used with phosphoric and citric acid buffers at a pH range between 3 and 7. Our results showed that cells were more viable in buffers with low rather than high ionic strength. A time-dependent effect of the acidification treatment was also observed with cell metabolic activity varying with treatment duration and frequency. Our results showed that a 24 h treatment and subsequent resting phase significantly improved cell proliferation and migration. This in vitro study is the first to establish a correlation between the role of acidic pH, molarity and treatment regimen in cellular activity. Our data demonstrated a positive effect of acidic pH on cell metabolic activity and migration rate, suggesting a clinical potential in indications such as wound healing.


Assuntos
Pele , Cicatrização , Movimento Celular , Proliferação de Células , Fibroblastos , Humanos , Queratinócitos/metabolismo , Pele/lesões
4.
Int J Mol Sci ; 23(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36362441

RESUMO

There has been little understanding of acidification functionality in wound healing, highlighting the need to study the efficacy of wound acidification on wound closure and cellular activity in non-infected wounds. This study is focused on establishing the healing potential of wound acidification in non-infected wounds. Acidic buffers, constituting either phosphoric or citric acid, were employed to modify the physiological pH of non-infected full-thickness excisional murine wounds. Acidification of the wound by acidic buffers was found to be an effective strategy to improve wound healing. A significant improvement in wound healing parameters was observed as early as 2 days post-treatment with acidic buffers compared to controls, with faster rate of epithelialization, wound closure and higher levels of collagen at day 7. pH is shown to play a role in mediating the rate of wound healing, with acidic buffers formulated at pH 4 observed to stimulate faster recovery of wounded tissues than pH 6 buffers. Our study shows the importance of maintaining an acidic wound microenvironment at pH 4, which could be a potential therapeutic strategy for wound management.


Assuntos
Reepitelização , Cicatrização , Camundongos , Animais , Cicatrização/fisiologia , Colágeno , Concentração de Íons de Hidrogênio , Pele/lesões
5.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299000

RESUMO

Parkinson's disease (PD) is the most common movement disorder, characterized by progressive degeneration of the nigrostriatal pathway, which consists of dopaminergic cell bodies in substantia nigra and their neuronal projections to the striatum. Moreover, PD is associated with an array of non-motor symptoms such as olfactory dysfunction, gastrointestinal dysfunction, impaired regulation of the sleep-wake cycle, anxiety, depression, and cognitive impairment. Inflammation and concomitant oxidative stress are crucial in the pathogenesis of PD. Thus, this study aimed to model PD via intrastriatal injection of the inflammagen lipopolysaccharide (LPS)to investigate if the lesion causes olfactory and motor impairments, inflammation, oxidative stress, and alteration in synaptic proteins in the olfactory bulb, striatum, and colon. Ten µg of LPS was injected unilaterally into the striatum of 27 male C57BL/6 mice, and behavioural assessment was conducted at 4 and 8 weeks post-treatment, followed by tissue collection. Intrastriatal LPS induced motor impairment in C57BL/6 mice at 8 weeks post-treatment evidenced by reduced latency time in the rotarod test. LPS also induced inflammation in the striatum characterized by increased expression of microglial marker Iba-1 and astrocytic marker GFAP, with degeneration of dopaminergic neuronal fibres (reduced tyrosine hydroxylase immunoreactivity), and reduction of synaptic proteins and DJ-1 protein. Additionally, intrastriatal LPS induced inflammation, oxidative stress and alterations in synaptic proteins within the olfactory bulb, although this did not induce a significant impairment in olfactory function. Intrastriatal LPS induced mild inflammatory changes in the distal colon, accompanied by increased protein expression of 3-nitrotyrosine-modified proteins. This model recapitulated the major features of PD such as motor impairment and degeneration of dopaminergic neuronal fibres in the striatum, as well as some pathological changes in the olfactory bulb and colon; thus, this model could be suitable for understanding clinical PD and testing neuroprotective strategies.


Assuntos
Astrócitos/metabolismo , Colo/metabolismo , Corpo Estriado/metabolismo , Neurônios Dopaminérgicos/metabolismo , Lipopolissacarídeos/metabolismo , Bulbo Olfatório/metabolismo , Doença de Parkinson/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Escala de Avaliação Comportamental , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Colo/patologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/patologia , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Inflamação/metabolismo , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microglia/metabolismo , Microglia/patologia , Bulbo Olfatório/efeitos dos fármacos , Bulbo Olfatório/patologia , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/patologia , Doença de Parkinson/psicologia , Proteína Desglicase DJ-1/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Substância Negra/metabolismo , Substância Negra/patologia , Tirosina 3-Mono-Oxigenase/metabolismo , alfa-Sinucleína/metabolismo
6.
Molecules ; 26(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33406699

RESUMO

Conventional chemotherapies used for breast cancer (BC) treatment are non-selective, attacking both healthy and cancerous cells. Therefore, new technologies that enhance drug efficacy and ameliorate the off-target toxic effects exhibited by currently used anticancer drugs are urgently needed. Here we report the design and synthesis of novel mesoporous silica nanoparticles (MSNs) equipped with the hormonal drug tamoxifen (TAM) to facilitate guidance towards estrogen receptors (ERs) which are upregulated in breast tumours. TAM is linked to the MSNs using a poly-ʟ-histidine (PLH) polymer as a pH-sensitive gatekeeper, to ensure efficient delivery of encapsulated materials within the pores. XRD, HR-TEM, DLS, SEM, FT-IR and BET techniques were used to confirm the successful fabrication of MSNs. The MSNs have a high surface area (>1000 m2/g); and a mean particle size of 150 nm, which is an appropriate size to allow the penetration of premature blood vessels surrounding breast tumours. Successful surface functionalization was supported by FT-IR, XPS and TGA techniques, with a grafting ratio of approximately 29%. The outcomes of this preliminary work could be used as practical building blocks towards future formulations.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Nanopartículas/administração & dosagem , Dióxido de Silício/química , Tamoxifeno/farmacologia , Antineoplásicos Hormonais/química , Composição de Medicamentos , Desenho de Fármacos , Descoberta de Drogas , Liberação Controlada de Fármacos , Feminino , Humanos , Nanopartículas/química , Porosidade , Tamoxifeno/química
7.
Int J Mol Sci ; 21(1)2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31947962

RESUMO

Herpes Simplex Virus Type 2 (HSV-2) is one of the most prevalent sexually transmitted viruses and is a known risk factor for HIV acquisition in the Female Genital Tract (FGT). Previously, we found that curcumin can block HSV-2 infection and abrogate the production of inflammatory cytokines and chemokines by genital epithelial cells in vitro. In this study, we investigated whether curcumin, encapsulated in nanoparticles and delivered by various in vivo routes, could minimize inflammation and prevent or reduce HSV-2 infection in the FGT. Female mice were pre-treated with curcumin nanoparticles through oral, intraperitoneal and intravaginal routes, and then exposed intravaginally to the tissue inflammation stimulant CpG-oligodeoxynucleotide (ODN). Local intravaginal delivery of curcumin nanoparticles, but not intraperitoneal or oral delivery, reduced CpG-mediated inflammatory histopathology and decreased production of pro-inflammatory cytokines Interleukin (IL)-6, Tumor Necrosis Factor Alpha (TNF-α) and Monocyte Chemoattractant Protein-1 (MCP-1) in the FGT. However, curcumin nanoparticles did not demonstrate anti-viral activity nor reduce tissue pathology when administered prior to intravaginal HSV-2 infection. In an alternative approach, intravaginal pre-treatment with crude curcumin or solid dispersion formulations of curcumin demonstrated increased survival and delayed pathology following HSV-2 infection. Our results suggest that curcumin nanoparticle delivery in the vaginal tract could reduce local tissue inflammation. The anti-inflammatory properties of curcumin delivered to the vaginal tract could potentially reduce the severity of HSV-2 infection and decrease the risk of HIV acquisition in the FGT of women.


Assuntos
Curcumina/farmacologia , Herpes Simples/patologia , Inflamação/patologia , Administração Intravaginal , Animais , Quimiocina CCL2/metabolismo , Curcumina/química , Curcumina/uso terapêutico , Portadores de Fármacos/química , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Feminino , Genitália Feminina/citologia , Genitália Feminina/metabolismo , Herpes Simples/veterinária , Herpes Simples/virologia , Herpesvirus Humano 2/fisiologia , Humanos , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/química , Oligodesoxirribonucleotídeos/toxicidade , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/metabolismo , Vagina/metabolismo , Vagina/patologia
8.
Molecules ; 25(5)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32151063

RESUMO

Breast cancer (BC) is one of the leading causes of death from cancer in women; second only to lung cancer. Tamoxifen (TAM) is a hydrophobic anticancer agent and a selective estrogen modulator (SERM), approved by the FDA for hormone therapy of BC. Despite having striking efficacy in BC therapy, concerns regarding the dose-dependent carcinogenicity of TAM still persist, restricting its therapeutic applications. Nanotechnology has emerged as one of the most important strategies to solve the issue of TAM toxicity, owing to the ability of nano-enabled-formulations to deliver smaller concentrations of TAM to cancer cells, over a longer period of time. Various TAM-containing-nanosystems have been successfully fabricated to selectively deliver TAM to specific molecular targets found on tumour membranes, reducing unwanted toxic effects. This review begins with an outline of breast cancer, the current treatment options and a history of how TAM has been used as a combatant of BC. A detailed discussion of various nanoformulation strategies used to deliver lower doses of TAM selectively to breast tumours will then follow. Finally, a commentary on future perspectives of TAM being employed as a targeting vector, to guide the delivery of other therapeutic and diagnostic agents selectively to breast tumours will be presented.


Assuntos
Antineoplásicos Hormonais/química , Antineoplásicos Hormonais/farmacologia , Composição de Medicamentos , Tamoxifeno/química , Tamoxifeno/farmacologia , Nanomedicina Teranóstica , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Lipossomos , Micelas , Estrutura Molecular , Nanotecnologia , Tamoxifeno/uso terapêutico
9.
J Vet Pharmacol Ther ; 41(5): 746-754, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29971788

RESUMO

Increasing reports of multidrug-resistant bacterial infections in animals has created a need for novel antimicrobial agents that do not promote cross-resistance to critically important antimicrobial classes used in human medicine. In response to the recent emergence of antimicrobial resistance in several bovine mastitis pathogens, in vitro antimicrobial susceptibility was determined for four polyether ionophores (lasalocid, monensin, narasin and salinomycin) against Staphylococcus spp. and Streptococcus spp. isolated from clinical cases. In addition, erythrocyte haemolysis and WST-1 cell proliferation assays were used to assess in vitro mammalian cell cytotoxicity and biofilm susceptibility testing was performed using the minimum biofilm eradication concentration (MBEC™) biofilm assay. Lasalocid, monensin, narasin and salinomycin exhibited bacteriostatic antimicrobial activity against all pathogens tested, including methicillin-resistant staphylococci, with MIC90 values <16 µg/ml. Narasin and monensin displayed the least toxicity against mammalian cell lines and all compounds significantly reduced viable cell numbers in a Staphylococcus aureus biofilm. Based on in vitro characterization, all four ionophores offer potentially novel treatments against bovine mastitis but in vivo studies will be essential to determine whether acceptable safety and efficacy is present following intramammary administration.


Assuntos
Antibacterianos/uso terapêutico , Bactérias Gram-Positivas/efeitos dos fármacos , Ionóforos/uso terapêutico , Mastite Bovina/tratamento farmacológico , Animais , Biofilmes/efeitos dos fármacos , Bovinos , Feminino , Lasalocida/uso terapêutico , Mastite Bovina/microbiologia , Testes de Sensibilidade Microbiana/veterinária , Monensin/uso terapêutico , Piranos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/veterinária , Staphylococcus/efeitos dos fármacos , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/veterinária , Streptococcus/efeitos dos fármacos
10.
Molecules ; 23(6)2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29882751

RESUMO

This study was aimed at formulating a bioabsorbable, controlled-release, nanoemulgel of Quercetin, a potent antimicrobial and anti-inflammatory agent for the treatment of periodontitis that could improve its solubility and bioavailability. Screening of components was carried out based on the solubility studies. Nanoemulsion containing cinnamon oil as the oil phase, tween 80 and Carbitol® as the surfactant-cosurfactant mixture (Smix) and water as the aqueous phase containing 125 µg/200 µL of Quercetin was prepared by using spontaneous emulsification method. Nanoemulgel was prepared using 23% w/v poloxamer 407 as gel base. Comprehensive evaluation of the formulated nanoemulgel was carried out, and the optimized formulation was studied for drug release using Franz vertical diffusion cells. The formulated nanoemulgelexhibited a remarkable release of 92.4% of Quercetin at the end of 6 h, as compared to that of pure Quercetin-loaded gel (<3% release). The viscosity of the prepared nanoemulgel was found to be 30,647 ± 0.32 cPs at 37 °C. Also, molecular dynamics (MD) simulation was utilized to understand the gelation process and role of each component in the formulation. The present study revealed that the developed nanoemulgel of Quercetin could be a potential delivery system for clinical testing in periodontitis.


Assuntos
Simulação por Computador , Sistemas de Liberação de Medicamentos , Géis , Nanoestruturas , Periodontite/tratamento farmacológico , Quercetina/uso terapêutico , Difusão , Estabilidade de Medicamentos , Microscopia Eletrônica de Transmissão , Simulação de Dinâmica Molecular , Quercetina/farmacocinética , Termodinâmica
11.
Anal Bioanal Chem ; 409(26): 6141-6148, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28842738

RESUMO

A first of its kind, simple, rapid, and sensitive liquid chromatography mass spectrometry (LC-MS/MS) method was developed and validated for quantification of perindopril and perindoprilat in both human plasma and breast milk. The analytes and internal standards (phenazone and acetyl salicylic acid) were extracted from biological matrices by protein precipitation. A Phenomenex® C-18 column was used to provide an appropriate chromatographic separation of the analytes, followed by detection with tandem mass spectrometry. Gradient chromatographic and mass spectrometric detection conditions with mobile phases (A: 5% methanol + 0.1% formic acid in water v/v, and B: 95% methanol + 0.1% formic acid in water v/v) were developed to achieve a LOQ of 0.5 ng/mL in both human plasma and milk. The method was suitable of evaluating clinical samples. The mass transition was followed as m/z 369.10/172.00 for perindopril, m/z 339.00/168.10 for perindoprilat, m/z 188.90/55.95 for phenazone, and m/z 179.04/137.02 for acetyl salicylic acid. The developed method was optimized and validated with a linear range of 0.1-200 ng/mL (r 2 = better than 0.99 for both perindopril and perindoprilat). The precision and accuracy values were within 15% CV. The overall recovery of the analytes was 80-110%. The method has good specificity and repeatability. Stability studies were conducted in both human plasma and bovine milk for up to 3 months, at the storage conditions of 25, 4, and -80 °C.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/análise , Inibidores da Enzima Conversora de Angiotensina/sangue , Indóis/análise , Indóis/sangue , Leite Humano/química , Perindopril/análise , Perindopril/sangue , Aleitamento Materno , Cromatografia Líquida/economia , Cromatografia Líquida/métodos , Feminino , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/economia , Espectrometria de Massas em Tandem/métodos
12.
Vet Dermatol ; 28(4): 342-e74, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28470877

RESUMO

BACKGROUND: Topical antimicrobial preparations are of utmost importance in treating suspected and confirmed meticillin-resistant Staphylococcus pseudintermedius (MRSP) infections due to the increasing incidence of widespread resistance to systemic antimicrobials. Lasalocid is active against MRSP in vitro and this may become an important topical antimicrobial for the treatment of canine pyoderma. HYPOTHESIS/OBJECTIVES: To determine effects of various formulation types on penetration and retention of lasalocid applied to canine skin in vitro. ANIMALS: Normal canine skin was collected from the thorax of five dogs that had been euthanized on the basis of health and/or intractable behavioural issues. METHODS: Solution, lotion and ointment containing 2% lasalocid were applied to ex vivo canine skin. Transdermal penetration was assessed for a 24 h period and retention of lasalocid was assessed at the conclusion of the study. RESULTS: The solution had significantly higher skin retention of lasalocid and proportion of applied dose retained in skin than lotion and ointment (Tukey-Kramer Honest Significant Difference test, P < 0.01). Lasalocid could not be detected in the receptor fluid of any Franz cell at any time point. CONCLUSIONS AND CLINICAL IMPORTANCE: Lasalocid was not identified in the receptor fluid of any sample, indicating that systemic absorption of the active ingredient in vivo is unlikely. Lasalocid may be useful in the treatment of MRSP infections if in vivo studies support safety and efficacy.


Assuntos
Antibacterianos/farmacocinética , Lasalocida/farmacocinética , Pele/metabolismo , Administração Cutânea , Animais , Antibacterianos/administração & dosagem , Cães , Composição de Medicamentos/veterinária , Feminino , Técnicas In Vitro , Lasalocida/administração & dosagem , Masculino
13.
AAPS PharmSciTech ; 18(1): 130-137, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26895019

RESUMO

Esophageal cancer (EC) mostly affects the elderly population and is frequently diagnosed at an advanced stage. Self-expanding metal stents (SEMS) are the most popular mode of palliation, but they are associated with reocclusion caused by tumor growth. To overcome this problem, docetaxel (DTX)-loaded polyurethane formulations were prepared for stent application. The films were evaluated against the cancer cell lines, OE-19 and OE-21, and normal esophageal cell line Het-1A. The DTX and the formulations were evaluated in vitro for the cytotoxicity and in vivo in nude mice. It was found that DTX and the formulations have a weak activity against the EC cell lines and an even weaker activity against Het-1A cell line. Preliminary in vivo studies showed skin toxicity in nude mice necessitating modification of the formulation. Reevaluation in a mouse xenograft model resulted in toxicity at high dose formulations while the low dose formulation exhibited modest advantage over commercial IV formulation; however, there was no significant difference between the commercial IV and blank formulation. DTX combination with an anti-cancer agent having complementary mode of action and non-overlapping toxicity could yield better outcome in future.


Assuntos
Esôfago/efeitos dos fármacos , Taxoides/administração & dosagem , Taxoides/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Docetaxel , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Stents , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
14.
Mol Pharm ; 12(7): 2305-17, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-25936529

RESUMO

Esophageal cancer patients are often diagnosed as "advanced" cases. These patients are subjected to palliative stenting using self-expanding metallic stents (SEMS) to maintain oral alimentation. Unfortunately, SEMS get reoccluded due to tumor growth, in and over the stent struts. To investigate potential solutions to this problem, docetaxel (DTX) delivery films were prepared using PurSil AL 20 (PUS), which can be used as a covering material for the SEMS. Drug-polymer miscibility and interactions were studied. Bilayer films were prepared by adhering the blank film to the DTX loaded film in order to maintain the unidirectional delivery to the esophagus. In vitro release and the local DTX delivery were studied using in vitro permeation experiments. It was found that DTX and PUS were physically and chemically compatible. The bilayer films exhibited sustained release (>30 days) and minimal DTX permeation through esophageal tissues in vitro. The rate-determining step for the DTX delivery was calculated. It was found that >0.9 fraction of rate control lies with the esophageal tissues, suggesting that DTX delivery can be sustained for longer periods compared to the in vitro release observed. Thus, the bilayer films can be developed as a localized sustained delivery system in combination with the stent.


Assuntos
Neoplasias Esofágicas/tratamento farmacológico , Esôfago/efeitos dos fármacos , Taxoides/administração & dosagem , Taxoides/química , Animais , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Docetaxel , Sistemas de Liberação de Medicamentos/métodos , Polímeros/química , Stents , Suínos
15.
Crit Rev Immunol ; 34(1): 1-14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24579699

RESUMO

Adipose tissue historically was believed to be an inert tissue, functioning primarily in the storage of energy and thermal homeostasis. However, recent discoveries point toward a critical role for adipocytes in endocrine function as well as immune regulation. Excess body fat, accumulated through aging and/or a calorie-rich diet, is associated with many chronic metabolic and inflammatory diseases. Within the stromal vascular fraction of adipose tissue, macrophages and T cells accumulate with increasing tissue mass, secreting pro- or anti-inflammatory cytokines. In this review we discuss the current understanding of immune cell function in both diet-induced and age-related obesity. In both models of obesity, the classically activated, pro-inflammatory (M1) subtype takes precedence over the alternatively activated, anti-inflammatory (M2) macrophages, causing tissue necrosis and releasing pro-inflammatory cytokines like interleukin-6. Other distinct adipose tissue macrophage subtypes have been identified by surface marker expression and their functions characterized. Adipose tissue T cell recruitment to adipose tissue is also different between aging- and diet-induced obesity. Under both conditions, T cells exhibit restricted T-cell receptor diversity and produce higher levels of pro-inflammatory signals like interferon-γ and granzyme B relative to young or healthy mice. However, numbers of regulatory T cells are dramatically different between the 2 models of obesity. Taken together, these findings suggest models of age- and diet-induced obesity may be more distinct than previously thought, with many questions yet to be resolved in this multidimensional disease.


Assuntos
Tecido Adiposo/imunologia , Envelhecimento/imunologia , Macrófagos/imunologia , Obesidade/imunologia , Linfócitos T/imunologia , Animais , Citocinas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Camundongos
16.
Ther Drug Monit ; 37(6): 699-710, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26020161

RESUMO

Daptomycin is the first approved member of a new class of antimicrobials, the cyclic lipopeptides, and presents selective action against gram-positive bacteria, including methicillin- and vancomycin-resistant strains. Considering that resistance to daptomycin is rare, the drug has become very important for current clinical practice. This review covers daptomycin's physicochemical characteristics, antibacterial spectrum, mechanism of action, pharmacokinetics, clinical applications, side effects, drug interactions, and the analytical methods used to measure daptomycin in pharmaceutical products and biologic samples. Special attention has been given to therapeutic drug monitoring reports, as studies have shown its highly variable pharmacokinetics in specific circumstances, such as in patients suffering from critical illness, morbid obesity, severe sepsis, and kidney injury. For the same reason, methods described for therapeutic drug monitoring of daptomycin in the special patient population have been reviewed. In addition, the review presents a discussion of environmentally friendly analytical methods for daptomycin, which are necessary to reduce the impact of our activities on the environment. However, it was observed that there is a gap in the literature in this regard and further research involving the development of "green" methodologies for the analysis of daptomycin is necessary. The review will be useful to the clinical community in assisting with the responsible use of daptomycin, which is critical to prevent the emergence of resistant strains.


Assuntos
Antibacterianos/uso terapêutico , Daptomicina/uso terapêutico , Monitoramento de Medicamentos/métodos , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Daptomicina/farmacocinética , Daptomicina/farmacologia , Farmacorresistência Bacteriana , Bactérias Gram-Positivas/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos
17.
J Pharm Pharm Sci ; 18(4): 578-99, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26626250

RESUMO

PURPOSE: We have previously reported that the Australian Northern Kaanju (Kuuku I'yu) medicinal plant Dodonaea polyandra has anti-inflammatory activity. This is attributed largely to the presence of clerodane diterpenoids contained within the leaf resin. We envisaged developing a topical preparation to treat indications relating to skin inflammation. However, it was unknown whether the resin could be incorporated into a suitable dosage form while retaining the therapeutic value demonstrated in previous work. Therefore, the following study was undertaken to assess parameters of safety and efficacy for a prototype formulation containing the leaf resin extracted from D. polyandra. METHODS: Using the assessment criteria of optimum appearance, tactile feeling, spreadability and odour, 78 different formulations were developed. Formulation stability was assessed using a centrifugal test with preparations displaying phase separation further modified or re-formulated. A prototype formulation containing 5% w/w plant resin was selected and subjected to in vitro release studies. This was quantified through HPLC analysis using two major bioactive diterpenoids as reference. The prototype formulation was tested for efficacy in a TPA-induced acute murine skin inflammation model as well as a 3D human skin model for irritancy/toxicity (Epiderm™). RESULTS: The prototype resin cream was a chartreuse-coloured homogenous semisolid preparation that was readily spreadable upon contact with skin with no sensation of tackiness, residual greasiness, or irritation. The optimized cream showed no phase separation after 30 min centrifugation at 825 g. In the TPA-induced inflammation model, the resin formulation significantly reduced ear thickness and interleukin-1 beta levels in mouse ear tissue. The 5% w/w resin cream formulation showed no irritancy in a 3D human skin model. CONCLUSIONS: Our results demonstrate that bioactive resin from D. polyandra can be formulated into a stable and non-irritant semi-solid dosage form and reduce parameters of acute skin inflammation in vivo. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.


Assuntos
Anti-Inflamatórios/farmacologia , Fármacos Dermatológicos/farmacologia , Inflamação/tratamento farmacológico , Sapindaceae/química , Doença Aguda , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Austrália , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Fármacos Dermatológicos/administração & dosagem , Fármacos Dermatológicos/isolamento & purificação , Modelos Animais de Doenças , Diterpenos Clerodânicos/administração & dosagem , Diterpenos Clerodânicos/isolamento & purificação , Diterpenos Clerodânicos/farmacologia , Estabilidade de Medicamentos , Humanos , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Folhas de Planta , Pele/efeitos dos fármacos , Pele/patologia , Testes de Irritação da Pele
18.
J Dairy Res ; 82(4): 470-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26190128

RESUMO

Developing a reliable mastitis challenge infection model is required to test new intramammary antimicrobial preparations, other novel bovine mastitis treatments, and study mastitis pathogenesis. Three treatment groups of Holstein Friesian cows in active lactation were administered two doses (10(4) and 10(6) cfu/quarter) on a single occasion with one of the three Streptococcus uberis strains (BFR6019, MFF1283 and SA002) suspended in 5 ml of sterile PBS, administered via intramammary inoculation immediately after milking. All quarters that were challenged with S. uberis strains MLF1283 and BFR6019 showed clinical signs of mastitis on day 1 and 2 after the challenge. Strain SA002 had a lower rate of inducing clinical mastitis which was detected later than day 3 after the challenge. We successfully developed a rapid and reliable model for inducing experimental S. uberis mastitis with 100% success rate in cows in active lactation. On the basis of the correlation results between strains, RAPD fingerprinting results, clinical findings, and a 100% success rate of mastitis induction for low and high doses S. uberis strains MLF1283 and BFR6019, strain virulence seems to be a more important effect than challenge dose in induction of clinical mastitis following experimental challenge.


Assuntos
Mastite Bovina/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/classificação , Animais , Bovinos , Feminino , Lactação , Mastite Bovina/patologia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia
19.
Drug Dev Ind Pharm ; 41(11): 1847-55, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25721984

RESUMO

CONTEXT: Poor biopharmaceutical properties and toxicities associated with the intravenous formulation of docetaxel (DTX) necessitate the exploration of an alternate oral route of delivery. OBJECTIVE: This study aims at enhancing the solubility of poorly soluble drug, DTX with the help of solid dispersion (SD) technique. METHOD: DTX SDs were formulated with selected solubilizers, including Kollidon 12PF, Lutrol F68, Soluplus and Hydroxypropyl-ß-cyclodextrin in different weight ratios. Freeze-drying method was used to prepare the binary and ternary SDs. Kinetic solubility of the SDs was evaluated in order to select best DTX-solubilizer combination. Best performing combination was then characterized using differential scanning calorimeter (DSC), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). RESULTS AND DISCUSSION: Among all SDs tested, Soluplus outperformed all the excipients at equivalent weight ratio. Binary SD of DTX and Soluplus (1:10) resulted in the highest improvement in solubility (362.93 ± 11.01 µg/mL). This is approximately a 93-fold increment as compared to the solubility of crystalline DTX (3.9 ± 0.2 µg/mL). This exceptional performance can be attributed to solid-state transformation as well as micellization. CONCLUSION: Among all the excipients tested, Soluplus dispersion is the most promising candidate for oral formulation development.


Assuntos
Antineoplásicos/administração & dosagem , Excipientes/química , Polietilenoglicóis/química , Polivinil/química , Taxoides/administração & dosagem , Administração Oral , Antineoplásicos/química , Varredura Diferencial de Calorimetria , Química Farmacêutica/métodos , Docetaxel , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Liofilização , Microscopia Eletrônica de Varredura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Taxoides/química , Difração de Raios X
20.
Molecules ; 20(6): 9703-31, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-26016555

RESUMO

Lactoferrin (Lf), an iron-binding protein from the transferrin family has been reported to have numerous functions. Even though Lf was first isolated from milk, it is also found in most exocrine secretions and in the secondary granules of neutrophils. Antimicrobial and anti-inflammatory activity reports on lactoferrin identified its significance in host defense against infection and extreme inflammation. Anticarcinogenic reports on lactoferrin make this protein even more valuable. This review is focused on the structural configuration of iron-containing and iron-free forms of lactoferrin obtained from different sources such as goat, camel and bovine. Apart for emphasizing on the specific beneficial properties of lactoferrin from each of these sources, the general antimicrobial, immunomodulatory and anticancer activities of lactoferrin are discussed here. Implementation of nanomedicinial strategies that enhance the bioactive function of lactoferrin are also discussed, along with information on lactoferrin in clinical trials.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Quelantes de Ferro/farmacologia , Ferro/metabolismo , Lactoferrina/farmacologia , Animais , Anti-Infecciosos/imunologia , Anti-Infecciosos/metabolismo , Anti-Inflamatórios/imunologia , Anti-Inflamatórios/metabolismo , Antineoplásicos/imunologia , Antineoplásicos/metabolismo , Camelus , Bovinos , Ensaios Clínicos como Assunto , Cabras , Humanos , Imunidade Inata , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Quelantes de Ferro/metabolismo , Lactoferrina/imunologia , Lactoferrina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/patologia , Neutrófilos/imunologia , Neutrófilos/metabolismo
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