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1.
Braz. J. Pharm. Sci. (Online) ; 56: e18748, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285513

RESUMO

Conventional drug formulations are incapable of adequate delivery of proteins and peptides for therapeutic purposes. As these molecules have very short biological half-life, multiple dosing is required to achieve the desirable therapeutic effects. Microspheres are able to encapsulate proteins and peptide in the polymeric matrix while protecting them from enzymatic degradation. In this study Bovine Serum Albumin (BSA) matrix type microspheres were fabricated using Polylactide-co-glycolide (PLGA) by double emulsion solvent evaporation method. The effects of variables such as homogenizer speed, molecular weight of polymer and the effect of pH of the water phases, were investigated against factors such as drug loading, encapsulation efficiency, morphology, size, drug distribution and release profile of the microspheres. Results, suggested that an increase in homogenization speed leads to a decrease in microsphere size. The increase in homogenization speed also caused a significant effect on the release profile only when higher molecular weight of polymer had been used.. The pH change of the internal aqueous phase led to modification of surface morphology of spheres to a porous structure that significantly increased the total amount of released protein. Integrity of protein structure was intact as shown by SDS-PAGE. According to the results, it can be concluded that we achieved a reproducible method regarding controlled protein delivery for different sizes of particles.


Assuntos
Técnicas In Vitro/métodos , Preparações Farmacêuticas/análise , Proteínas , Microesferas , Soroalbumina Bovina/administração & dosagem , Eficiência/classificação , Eletroforese em Gel de Poliacrilamida/instrumentação , Emulsões
2.
Cochrane Database Syst Rev ; 3: CD002124, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-27000311

RESUMO

BACKGROUND: Dysmenorrhoea refers to painful menstrual cramps and is a common gynaecological complaint. Conventional treatments include non-steroidal anti-inflammatory drugs (NSAIDs) and oral contraceptive pills (OCPs), which both reduce myometrial activity (contractions of the uterus). A suggested alternative approach is dietary supplements. We used the term 'dietary supplement' to include herbs or other botanical, vitamins, minerals, enzymes, and amino acids. We excluded traditional Chinese medicines. OBJECTIVES: To determine the efficacy and safety of dietary supplements for treating dysmenorrhoea. SEARCH METHODS: We searched sources including the Cochrane Gynaecology and Fertility Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, AMED, PsycINFO (all from inception to 23 March 2015), trial registries, and the reference lists of relevant articles. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of dietary supplements for moderate or severe primary or secondary dysmenorrhoea. We excluded studies of women with an intrauterine device. Eligible comparators were other dietary supplements, placebo, no treatment, or conventional analgesia. DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection, performed data extraction and assessed the risk of bias in the included trials. The primary outcomes were pain intensity and adverse effects. We used a fixed-effect model to calculate odds ratios (ORs) for dichotomous data, and mean differences (MDs) or standardised mean differences (SMDs) for continuous data, with 95% confidence intervals (CIs). We presented data that were unsuitable for analysis either descriptively or in additional tables. We assessed the quality of the evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methods. MAIN RESULTS: We included 27 RCTs (3101 women). Most included studies were conducted amongst cohorts of students with primary dysmenorrhoea in their late teens or early twenties. Twenty-two studies were conducted in Iran and the rest were performed in other middle-income countries. Only one study addressed secondary dysmenorrhoea. Interventions included 12 different herbal medicines (German chamomile (Matricaria chamomilla, M recutita, Chamomilla recutita), cinnamon (Cinnamomum zeylanicum, C. verum), Damask rose (Rosa damascena), dill (Anethum graveolens), fennel (Foeniculum vulgare), fenugreek (Trigonella foenum-graecum), ginger (Zingiber officinale), guava (Psidium guajava), rhubarb (Rheum emodi), uzara (Xysmalobium undulatum), valerian (Valeriana officinalis), and zataria (Zataria multiflora)) and five non-herbal supplements (fish oil, melatonin, vitamins B1 and E, and zinc sulphate) in a variety of formulations and doses. Comparators included other supplements, placebo, no treatment, and NSAIDs.We judged all the evidence to be of low or very low quality. The main limitations were imprecision due to very small sample sizes, failure to report study methods, and inconsistency. For most comparisons there was only one included study, and very few studies reported adverse effects. Effectiveness of supplements for primary dysmenorrhoea We have presented pain scores (all on a visual analogue scale (VAS) 0 to 10 point scale) or rates of pain relief, or both, at the first post-treatment follow-up. Supplements versus placebo or no treatmentThere was no evidence of effectiveness for vitamin E (MD 0.00 points, 95% CI -0.34 to 0.34; two RCTs, 135 women).There was no consistent evidence of effectiveness for dill (MD -1.15 points, 95% CI -2.22 to -0.08, one RCT, 46 women), guava (MD 0.59, 95% CI -0.13 to 1.31; one RCT, 151 women); one RCT, 73 women), or fennel (MD -0.34 points, 95% CI -0.74 to 0.06; one RCT, 43 women).There was very limited evidence of effectiveness for fenugreek (MD -1.71 points, 95% CI -2.35 to -1.07; one RCT, 101 women), fish oil (MD 1.11 points, 95% CI 0.45 to 1.77; one RCT, 120 women), fish oil plus vitamin B1 (MD -1.21 points, 95% CI -1.79 to -0.63; one RCT, 120 women), ginger (MD -1.55 points, 95% CI -2.43 to -0.68; three RCTs, 266 women; OR 5.44, 95% CI 1.80 to 16.46; one RCT, 69 women), valerian (MD -0.76 points, 95% CI -1.44 to -0.08; one RCT, 100 women), vitamin B1 alone (MD -2.70 points, 95% CI -3.32 to -2.08; one RCT, 120 women), zataria (OR 6.66, 95% CI 2.66 to 16.72; one RCT, 99 women), and zinc sulphate (MD -0.95 points, 95% CI -1.54 to -0.36; one RCT, 99 women).Data on chamomile and cinnamon versus placebo were unsuitable for analysis. Supplements versus NSAIDSThere was no evidence of any difference between NSAIDs and dill (MD 0.13 points, 95% CI -1.01 to 1.27; one RCT, 47 women), fennel (MD -0.70 points, 95% CI -1.81 to 0.41; one RCT, 59 women), guava (MD 1.19, 95% CI 0.42 to 1.96; one RCT, 155 women), rhubarb (MD -0.20 points, 95% CI -0.44 to 0.04; one RCT, 45 women), or valerian (MD points 0.62 , 95% CI 0.03 to 1.21; one RCT, 99 women),There was no consistent evidence of a difference between Damask rose and NSAIDs (MD -0.15 points, 95% CI -0.55 to 0.25; one RCT, 92 women).There was very limited evidence that chamomile was more effective than NSAIDs (MD -1.42 points, 95% CI -1.69 to -1.15; one RCT, 160 women). Supplements versus other supplementsThere was no evidence of a difference in effectiveness between ginger and zinc sulphate (MD 0.02 points, 95% CI -0.58 to 0.62; one RCT, 101 women). Vitamin B1 may be more effective than fish oil (MD -1.59 points, 95% CI -2.25 to -0.93; one RCT, 120 women). Effectiveness of supplements for secondary dysmenorrhoea There was no strong evidence of benefit for melatonin compared to placebo for dysmenorrhoea secondary to endometriosis (data were unsuitable for analysis). Safety of supplements Only four of the 27 included studies reported adverse effects in both treatment groups. There was no evidence of a difference between the groups but data were too scanty to reach any conclusions about safety. AUTHORS' CONCLUSIONS: There is no high quality evidence to support the effectiveness of any dietary supplement for dysmenorrhoea, and evidence of safety is lacking. However for several supplements there was some low quality evidence of effectiveness and more research is justified.


Assuntos
Suplementos Nutricionais , Dismenorreia/terapia , Fitoterapia/métodos , Anti-Inflamatórios não Esteroides/uso terapêutico , Dismenorreia/dietoterapia , Feminino , Humanos , Magnésio/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Tiamina/uso terapêutico , Vitamina B 6/uso terapêutico , Vitamina E/uso terapêutico
3.
PLoS One ; 9(7): e102140, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25006803

RESUMO

The transcription factor SOX2 is essential for maintaining pluripotency in a variety of stem cells. It has important functions during embryonic development, is involved in cancer stem cell maintenance, and is often deregulated in cancer. The mechanism of SOX2 regulation has yet to be clarified, but the SOX2 gene lies in an intron of a long multi-exon non-coding RNA called SOX2 overlapping transcript (SOX2OT). Here, we show that the expression of SOX2 and SOX2OT is concordant in breast cancer, differentially expressed in estrogen receptor positive and negative breast cancer samples and that both are up-regulated in suspension culture conditions that favor growth of stem cell phenotypes. Importantly, ectopic expression of SOX2OT led to an almost 20-fold increase in SOX2 expression, together with a reduced proliferation and increased breast cancer cell anchorage-independent growth. We propose that SOX2OT plays a key role in the induction and/or maintenance of SOX2 expression in breast cancer.


Assuntos
Neoplasias da Mama/genética , RNA Longo não Codificante/genética , Fatores de Transcrição SOXB1/genética , Animais , Neoplasias da Mama/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Mamárias Experimentais , Camundongos , Células-Tronco Neoplásicas/metabolismo , Regulação para Cima
4.
Cancer Chemother Pharmacol ; 73(3): 639-49, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24477604

RESUMO

PURPOSE: Glioblastomas are amongst the most highly vascularised tumours, and the pursuit of anti-angiogenic approaches such as bevacizumab has provided short-term benefits. The purpose of this study was to determine whether the vascular-disrupting agent, dimethylxanthenone-4-acetic acid (DMXAA), could provide longer-lasting therapeutic benefits in a murine model of glioblastoma. METHODS: Luciferase-expressing murine GL261 glioma cells were inoculated subcutaneously or intracranially into C57Bl/6 mice. Mice with tumours were administered DMXAA, and tumours measured using callipers or by optical imager. Concentrations of DMXAA in plasma and brain were measured by LC-MS/MS. RESULTS: DMXAA (25 mg/kg) caused widespread necrosis at 24 h, a 9-day growth delay and complete regressions in 50 % of the mice with subcutaneous GL261 tumours. Co-administered lenalidomide (100 mg/kg) increased the growth delay to 20 days and the percentage of cures to 83 %. The same dose of DMXAA with or without lenalidomide had minimal effects on intracranial GL261 tumours. Concentrations of DMXAA extracted from brain tissue were approximately 25-fold lower than those measured in plasma 15 min to 4 h after DMXAA administration. The presence of intracranial GL261 tumours did not alter the concentrations of DMXAA entering the brain. CONCLUSIONS: DMXAA does not appear to cross the blood-brain barrier efficiently. Thus, whilst excellent activity was obtained against subcutaneous GL261 gliomas, minimal effects were observed against intracranial GL261 tumours. These results emphasise the need to use appropriate orthotopic models for the evaluation of new approaches for the treatment of brain cancers.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Xantonas/farmacologia , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Glioma/sangue , Glioma/irrigação sanguínea , Glioma/metabolismo , Infusões Subcutâneas , Lenalidomida , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/tratamento farmacológico , Distribuição Aleatória , Talidomida/análogos & derivados , Talidomida/farmacologia , Xantonas/sangue , Xantonas/farmacocinética
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