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1.
BDJ Open ; 7(1): 23, 2021 Jun 25.
Article in English | MEDLINE | ID: mdl-34172718

ABSTRACT

OBJECTIVE: The objective of this study was to investigate and compare the effectiveness of several toothpastes containing nanohydroxyapatite (nano-HAP) to relieve dentin hypersensitivity (DHS) with that of a commercial desensitizing dentifrice containing calcium sodium phosphosilicate (CSPS). MATERIALS AND METHODS: In this double-blind, randomized, parallel-group clinical trial, patients diagnosed with DHS and qualified to participate were randomized into four groups: toothpaste containing 10% nano-HAP (10%nano-HAP), 15% nano-HAP (15%nano-HAP), 10% nano-HAP supplemented with potassium nitrate (KNO3) (10%nano-HAPKN), or CSPS. Subjects' baseline and post-treatment sensitivities were assessed using visual analog scale (VAS) after the application of ice-cold and air stimuli. Subjects used their assigned toothpaste for routine toothbrushing twice daily. Post-treatment sensitivity was assessed every 2 or 8 weeks. Mean change in VAS (mm) from baseline at each time point were compared using random-intercept, mixed-model analysis and Duncan test (P < 0.05). RESULTS: With either air or cold stimulus, VAS indicated a significant (P < 0.001) reduction from baseline DHS at each time point with all test toothpastes. Among the nano-HAP toothpastes, 15%nano-HAP and 10%nano-HAPKN were consistent in DHS reduction with both stimuli. With either stimuli, the CSPS did not significantly differ from 15%nano-HAP and 10%nano-HAPKN at any time point. CONCLUSIONS: Toothpaste containing nano-HAP (10 or 15%) alone or supplemented with KNO3 was as effective as CSPS for relief of DHS symptoms when used at least twice daily.

2.
Open Dent J ; 12: 572-585, 2018.
Article in English | MEDLINE | ID: mdl-30288181

ABSTRACT

OBJECTIVE: The study aimed to investigate the effectiveness of Apadent Pro (Sangi) Nanohydroxyapatite (nHAP) dental cream to relieve Dentin Hypersensitivity (DHS), compared with a positive control cream containing 20% pure silica (Silica). METHODS: In this double-blind, randomized, parallel-group clinical trial, patients diagnosed with DHS and qualified to participate were randomized into two groups, nHAP (n=25) and Silica (n=26). Subjects' baseline and posttreatment sensitivity were assessed using two pain scales, a four-point Dental Pain Scale (DPS) followed by a linear Visual Analog Scale (VAS), after the application of ice-cold and air stimuli. Subjects used custom-fabricated trays to apply their respective cream for 5 minutes once daily following brushing with standard fluoride toothpaste. Posttreatment sensitivity (efficacy) was assessed every 2 weeks for 8 weeks. Mean treatment outcomes (percentage change from baseline) at each time point were compared using the Tukey HSD test for multiplicity (P<0.05). RESULTS: With either air or cold stimulus, VAS and DPS indicated a significant (P<0.001) reduction in DHS at each time point with either nHAP or Silica. Comparing pain scales, VAS showed no significant difference in DHS reduction between the products with either air or cold. However, with DPS, DHS reduction was significantly (P<0.05) better with Silica than with nHAP at all time points with cold, and at 2, 4, and 8 weeks with air. CONCLUSION: Both Apadent Pro nHAP and Silica dental creams are effective at promoting the relief of DHS symptoms. When comparing the efficacy of the two compounds to relieve DHS, results of the two pain scales were conflicting.

3.
J Otolaryngol Head Neck Surg ; 46(1): 63, 2017 Nov 22.
Article in English | MEDLINE | ID: mdl-29166927

ABSTRACT

BACKGROUND: Chronic suppurative otitis media can be recalcitrant and difficult to treat, particularly with the increasing occurrence of antibiotic resistance. Lactobacillus plantarum is a probiotic that has been shown to decrease S. aureus and P. aeruginosa growth in wounds, making it a good candidate for the treatment of chronic suppurative otitis media. However, before it can be applied in the ear, its ototoxicity potential must be evaluated. METHODS: A prospective controlled trial was conducted in a chinchilla animal model at the Animal care research facilities of the Montreal Children's Hospital Research Institute to determine whether Lactobacillus plantarum is ototoxic when applied transtympanically. Ten chinchillas each had one ear randomly assigned to receive 109 CFU/mL of Lactobacillus plantarum solution, while the contralateral ear received saline. Auditory brainstem responses were measured bilaterally at 8, 20, 25 kHz before, at 7-10 days after application, and at 28 days after application of probiotic or saline. Facial nerve and vestibular function were assessed clinically. RESULTS: There were no statistically significant differences in hearing thresholds between control and experimental ears at 28 days after application. A difference of 11 dB was noted in the 25 kHz range at day 7-10, but resolved by day 28. No animals receiving probiotics developed vestibular nerve dysfunction. There was no histologic evidence of auditory hair cell damaged evidenced by scanning electron microscopy. CONCLUSION: Our study suggests that a single application of Lactobacillus plantarum at 109 CFU/mL does not cause ototoxicity in a chinchilla animal model. These preliminary safety evaluations and the pathogen inhibitory effects of L. plantarum demonstrated by previous studies present this probiotic as a candidate of interest for further investigation.


Subject(s)
Otitis Media, Suppurative/drug therapy , Probiotics/administration & dosage , Tympanic Membrane/drug effects , Administration, Topical , Animals , Chinchilla , Chronic Disease , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Follow-Up Studies , Hearing Tests/methods , Otitis Media, Suppurative/microbiology , Random Allocation , Reference Values , Risk Assessment , Treatment Outcome
4.
Pract Radiat Oncol ; 7(3): 183-189, 2017.
Article in English | MEDLINE | ID: mdl-28477798

ABSTRACT

PURPOSE: Our purpose was to evaluate hippocampal doses and target volume coverage with and without hippocampal sparing when treating multiple brain metastases using various stereotactic radiosurgery (SRS) platforms. METHODS AND MATERIALS: We selected 10 consecutive patients with 14 separate treatments who had been treated in our department for 3 to 10 brain metastases and added hippocampal avoidance contours. All 14 treatments were planned with GammaPlan for Gamma Knife, Eclipse for single isocenter volumetric modulated arc therapy (VMAT), TomoTherapy Treatment Planning System (TPS) for TomoTherapy, and MultiPlan for CyberKnife. Initial planning was performed with the goal of planning target volume coverage of V100 ≥95% without hippocampal avoidance. If the maximum hippocampal point dose (Dmax) was <6.6 Gy in a single fraction and <40% of the hippocampi received ≤4.5 Gy, no second plan was performed. If either constraint was not met, replanning was performed with these constraints. RESULTS: There was a median of 6 metastases per plan, with an average total tumor volume of 7.32 mL per plan. The median hippocampal Dmax (in Gy) without sparing averaged 1.65, 9.81, 4.38, and 5.46, respectively (P < .0001). Of 14 plans, 3 Gamma Knife and CyberKnife plans required replanning, whereas 13 VMAT and 8 TomoTherapy plans required replanning. The hippocampal constraints were not achievable in 1 plan on any platform when the tumor was bordering the hippocampus. The mean volume of brain receiving 12 Gy (in mL), which has been associated with symptomatic radionecrosis, was 23.57 with Gamma Knife, 76.77 with VMAT, 40.86 with CyberKnife, and 104.06 with TomoTherapy (P = .01). The overall average conformity indices for all plans ranged from 0.36 to 0.52. CONCLUSIONS: Even with SRS, the hippocampi can receive a considerable dose; however, if the hippocampi are outlined as organs of risk, sparing these structures is feasible in nearly all situations with all 4 platforms, without detriment to target coverage, and should be considered in all patients undergoing SRS for multiple brain metastases. SUMMARY: Hippocampi play an important role in memory, and sparing of these structures in whole brain radiation can improve neurocognitive outcomes. The hippocampi are not routinely spared when using stereotactic radiosurgery. We evaluated the incidental dose to the hippocampi when treating multiple brain metastases and sought to examine if hippocampal sparing is feasible without detriment to target coverage. We found that hippocampal sparing is possible without affecting coverage or conformality in most cases across treatment platforms.


Subject(s)
Brain Neoplasms/radiotherapy , Hippocampus , Organ Sparing Treatments/methods , Radiosurgery/methods , Radiotherapy, Intensity-Modulated/methods , Brain Neoplasms/pathology , Brain Neoplasms/secondary , Hippocampus/radiation effects , Humans , Radiosurgery/adverse effects , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/adverse effects , Treatment Outcome , Tumor Burden/radiation effects
5.
Front Plant Sci ; 8: 386, 2017.
Article in English | MEDLINE | ID: mdl-28377784

ABSTRACT

Understanding environmental responses of pulse crop species and their wild relatives will play an important role in developing genetic strategies for crop improvement in response to changes in climate. This study examined how cultivated lentil and wild Lens germplasm responded to different light environments, specifically differences in red/far-red ratio (R/FR) and photosynthetically active radiation (PAR). Three genotypes of each the seven Lens species were grown in environmentally controlled growth chambers equipped to provide light treatments consisting of different R/FR ratios and PAR values. Our results showed that overall, days to flower of Lens genotypes were mainly influenced by the R/FR induced light quality change but not by the PAR related light intensity change. The cultivated lentil (L. culinaris) showed consistent, accelerated flowering in response to the low R/FR light environment together with three wild lentil genotypes (L. orientalis IG 72611, L. tomentosus IG 72830, and L. ervoides IG 72815) while most wild lentil genotypes had reduced responses and flowering time was not significantly affected. The longest shoot length, longest internode length, and largest leaflet area were observed under the low R/FR low PAR environment for both cultivated and wild lentils. The distinctly different responses between flowering time and elongation under low R/FR conditions among wild Lens genotypes suggests discrete pathways controlling flowering and elongation, which are both components of shade avoidance responses. The yield and above-ground biomass of Lens genotypes were the highest under high R/FR high PAR conditions, intermediate under low R/FR low PAR conditions, and lowest under high R/FR low PAR light conditions. Three L. lamottei genotypes (IG 110809, IG 110810, and IG 110813) and one L. ervoides genotype (IG 72646) were less sensitive in their time to flower responses while maintaining similar yield, biomass, and harvest index across all three light environments; these are indications of better adaptability toward changes in light environment.

6.
Biomed Res Int ; 2014: 380316, 2014.
Article in English | MEDLINE | ID: mdl-25295259

ABSTRACT

Excess cholesterol is associated with cardiovascular diseases (CVD), an important cause of mortality worldwide. Current CVD therapeutic measures, lifestyle and dietary interventions, and pharmaceutical agents for regulating cholesterol levels are inadequate. Probiotic bacteria have demonstrated potential to lower cholesterol levels by different mechanisms, including bile salt hydrolase activity, production of compounds that inhibit enzymes such as 3-hydroxy-3-methylglutaryl coenzyme A, and cholesterol assimilation. This work investigates 11 Lactobacillus strains for cholesterol assimilation. Probiotic strains for investigation were selected from the literature: Lactobacillus reuteri NCIMB 11951, L. reuteri NCIMB 701359, L. reuteri NCIMB 702655, L. reuteri NCIMB 701089, L. reuteri NCIMB 702656, Lactobacillus fermentum NCIMB 5221, L. fermentum NCIMB 8829, L. fermentum NCIMB 2797, Lactobacillus rhamnosus ATCC 53103 GG, Lactobacillus acidophilus ATCC 314, and Lactobacillus plantarum ATCC 14917. Cholesterol assimilation was investigated in culture media and under simulated intestinal conditions. The best cholesterol assimilator was L. plantarum ATCC 14917 (15.18±0.55 mg/10(10) cfu) in MRS broth. L. reuteri NCIMB 701089 assimilated over 67% (2254.70±63.33 mg/10(10) cfu) of cholesterol, the most of all the strains, under intestinal conditions. This work demonstrates that probiotic bacteria can assimilate cholesterol under intestinal conditions, with L. reuteri NCIMB 701089 showing great potential as a CVD therapeutic.


Subject(s)
Amidohydrolases/metabolism , Cholesterol/metabolism , Lactobacillus plantarum/metabolism , Probiotics/metabolism , Acyl Coenzyme A/antagonists & inhibitors , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/pathology , Culture Media , Humans , In Vitro Techniques , Probiotics/therapeutic use
7.
Biomed Res Int ; 2014: 602832, 2014.
Article in English | MEDLINE | ID: mdl-24967382

ABSTRACT

The gut microbiota is a bacterial bioreactor whose composition is an asset for human health. However, circulating gut microbiota derived endotoxins cause metabolic endotoxemia, promoting metabolic and liver diseases. This study investigates the potential of orally delivered microencapsulated Bifidobacterium infantis ATCC 15697 to modulate the gut microbiota and reduce endotoxemia in F344 rats. The rats were gavaged daily with saline or microencapsulated B. infantis ATCC 15697. Following 38 days of supplementation, the treated rats showed a significant (P < 0.05) increase in fecal Bifidobacteria (4.34 ± 0.46 versus 2.45 ± 0.25% of total) and B. infantis (0.28 ± 0.21 versus 0.52 ± 0.12 % of total) and a significant (P < 0.05) decrease in fecal Enterobacteriaceae (0.80 ± 0.45 versus 2.83 ± 0.63% of total) compared to the saline control. In addition, supplementation with the probiotic formulation reduced fecal (10.52 ± 0.18 versus 11.29 ± 0.16 EU/mg; P = 0.01) and serum (0.33 ± 0.015 versus 0.30 ± 0.015 EU/mL; P = 0.25) endotoxins. Thus, microencapsulated B. infantis ATCC 15697 modulates the gut microbiota and reduces colonic and serum endotoxins. Future preclinical studies should investigate the potential of the novel probiotic formulation in metabolic and liver diseases.


Subject(s)
Bifidobacterium , Colon/metabolism , Colon/microbiology , Endotoxins/blood , Microbiota , Animals , Endotoxemia/blood , Endotoxemia/microbiology , Endotoxemia/therapy , Humans , Male , Rats , Rats, Inbred F344
8.
Methods Mol Biol ; 1141: 233-47, 2014.
Article in English | MEDLINE | ID: mdl-24567143

ABSTRACT

Neurodegeneration is characterized by a progressive loss of neuron structure and function. Most neurodegenerative diseases progress slowly over the time. There is currently no cure available for any neurodegenerative disease, and the existing therapeutic interventions only alleviate the symptoms of the disease. The advances in the drug discovery research have come to a halt with a lack of effective means to deliver drugs at the targeted site. In addition, the route of delivering the drugs is equally important as most invasive techniques lead to postoperative complications. This chapter focuses on a non-invasive, intranasal mode of therapeutic delivery using nanoparticles, which is currently being explored. The intranasal route of delivery is a well-established route to deliver drugs via the olfactory and trigeminal neuronal pathways. It is known to be the fastest and most effective way to bypass the blood-brain barrier to reach the central nervous system. The presented chapter highlights the method of intranasal delivery in mice using chitosan-siRNA nanoparticle formulation, under mild anesthesia and the identification of successful siRNA delivery in the brain tissues, through histology and other well-established laboratory protocols.


Subject(s)
Chitosan/metabolism , Drug Delivery Systems/methods , Olfactory Bulb/metabolism , RNA, Small Interfering/metabolism , Trigeminal Nerve/metabolism , Administration, Intranasal , Anesthetics, Inhalation , Animals , Biological Transport , Biotin/chemistry , Blood-Brain Barrier , Chitosan/chemistry , Histocytochemistry , Isoflurane , Mice , RNA, Small Interfering/chemistry
9.
Curr Pharm Des ; 20(6): 1025-37, 2014.
Article in English | MEDLINE | ID: mdl-23701572

ABSTRACT

Allergy, also termed type I hypersensitivity, is defined as a "disease following a response by the immune system to an otherwise innocuous antigen". The prevalence of allergies is high and escalating, with almost half the populations of North America and Europe having allergies to one or more common environmental antigens. Although rarely life-threatening allergies cause much distress and pose an important economic burden. Recent studies demonstrate the importance of the commensal bacteria of the gastrointestinal tract, termed the microbiota, in stimulating and modulating the immune system. This goes hand-in-hand with the hygiene hypothesis, proposed by Strachan in 1989. With this in mind, the use of pre- and probiotics has gained interest to prevent and treat allergies through modulation of the gut microbiota and the immune system. Probiotics, namely Lactobacilli and Bifidobacteria, are live microorganisms that can be incorporated in the diet in the form of functional foods or dietary supplements to beneficially influence the host. In recent studies, probiotic formulations demonstrated the capability to successfully modulate allergic rhinitis, atopic disorders and food-related allergies. A number of probiotic mechanisms of action are involved in controlling hypersensitivity responses, many of which are still not yet understood. Microencapsulation has gained importance as a device for the oral delivery of probiotic cells and may play an important role in the development of a successful probiotic formulation to treat and prevent allergies. Despite the promising research on probiotic biotherapeutics, further investigations are required to develop a successful therapeutic to treat and prevent allergies.


Subject(s)
Gastrointestinal Tract/immunology , Hypersensitivity, Immediate/therapy , Probiotics/therapeutic use , Animals , Antigens/immunology , Bifidobacterium , Gastrointestinal Tract/microbiology , Humans , Hypersensitivity/immunology , Hypersensitivity/prevention & control , Hypersensitivity/therapy , Hypersensitivity, Immediate/immunology , Hypersensitivity, Immediate/prevention & control , Immune System/immunology , Lactobacillus , Probiotics/administration & dosage , Probiotics/pharmacology
10.
Appl Microbiol Biotechnol ; 98(1): 115-26, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24121931

ABSTRACT

Metabolic syndrome, encompassing type 2 diabetes mellitus and cardiovascular disease, is a growing health concern of industrialized countries. Ferulic acid (FA) is a phenolic acid found in foods normally consumed by humans that has demonstrated antioxidant activity, cholesterol-lowering capabilities, and anti-tumorigenic properties. Select probiotic bacteria, including Lactobacillus fermentum NCIMB 5221, produce FA due to intrinsic ferulic acid esterase activity. The aim of the present research was to investigate a FA-producing probiotic, L. fermentum NCIMB 5221, as a biotherapeutic for metabolic syndrome. The probiotic formulation was administered daily for 8 weeks to Zucker diabetic fatty (ZDF) rats, a model of hyperlipidemia and hyperglycemia. Results show that the probiotic formulation reduced fasting insulin levels and insulin resistance, significantly reduced serum triglycerides (p = 0.016), lowered serum low-density lipoprotein cholesterol levels (p = 0.008), and significantly reduced the atherogenic (p = 0.016) and atherosclerosis (p = 0.012) index as compared to the control animals. In addition, the probiotic formulation significantly increased high-density lipoprotein cholesterol levels (p = 0.041) as compared to the control animals. This research indicates that administration of the FA-producing L. fermentum NCIMB 5221 has the potential to reduce insulin resistance, hyperinsulinemia, hypercholesterolemia, and other markers involved in the pathogenesis of metabolic syndrome. Further studies are required to investigate the human clinical potential of the probiotic formulation in affecting the markers and pathogenesis of metabolic syndrome.


Subject(s)
Coumaric Acids/metabolism , Limosilactobacillus fermentum/growth & development , Limosilactobacillus fermentum/metabolism , Metabolic Syndrome/pathology , Metabolic Syndrome/therapy , Probiotics/administration & dosage , Probiotics/metabolism , Animals , Atherosclerosis/prevention & control , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Disease Models, Animal , Insulin/blood , Rats , Triglycerides/blood
11.
J Microencapsul ; 31(3): 230-8, 2014.
Article in English | MEDLINE | ID: mdl-24124888

ABSTRACT

This study evaluates alginate-poly-L-lysine-alginate Bifidobacterium longum subsp. infantis ATCC 15697-loaded microcapsules to enrich the human gut microbiota. The cell survival of alginate-poly-L-lysine-alginate microencapsulated B. infantis ATCC 15697 in gastric acid, bile, and through human gastrointestinal transit was investigated, as well as the formulation's effect on the gut microbiota. Results show that microencapsulation increases B. infantis ATCC 15697 cell survival at pH1.0 (33.54 ± 2.80% versus <1.00 ± 0.00%), pH1.5 (41.15 ± 2.06% versus <1.00 ± 0.00%), pH2.0 (60.88 ± 1.73% versus 36.01 ± 2.63%), pH3.0 (75.43 ± 1.23% versus 46.30 ± 1.43%), pH4.0 (71.40 ± 2.02% versus 47.75 ± 3.12%) and pH5.0 (73.88 ± 3.79% versus 58.93 ± 2.26%) (p < 0.05). In addition, microencapsulation increases cell survival at 0.5% (76.85 ± 0.80% versus 70.77 ± 0.64%), 1.0% (59.99 ± 0.97% versus 53.47 ± 0.58%) and 2.0% (53.10 ± 1.87% versus 44.59 ± 1.52%) (p < 0.05) (w/v) bile. Finally, daily administration of alginate-poly-L-lysine-alginate microencapsulated B. infantis ATCC 15697 in a human gastrointestinal model induces a significant enrichment of B. infantis within the ascending (184.51 ± 17.30% versus 53.83 ± 17.82%; p < 0.05), transverse (174.79 ± 25.32% versus 73.17 ± 15.30%; p < 0.05) and descending (94.90 ± 25.22% versus 46.37 ± 18.93%; p > 0.05) colonic microbiota.


Subject(s)
Alginates , Bifidobacterium , Computer Simulation , Intestines/microbiology , Microbiota , Models, Biological , Polylysine/analogs & derivatives , Stomach/microbiology , Administration, Oral , Alginates/chemistry , Alginates/pharmacokinetics , Alginates/pharmacology , Capsules , Humans , Polylysine/chemistry , Polylysine/pharmacokinetics , Polylysine/pharmacology
12.
Int J Biomater ; 2013: 252531, 2013.
Article in English | MEDLINE | ID: mdl-24159333

ABSTRACT

Polymeric nanoparticles were developed from a series of chemical reactions using chitosan, polyethylene glycol, and a cell-targeting peptide (CP15). The nanoparticles were complexed with PLK1-siRNA. The optimal siRNA loading was achieved at an N : P ratio of 129.2 yielding a nanoparticle size of >200 nm. These nanoparticles were delivered intraperitoneally and tested for efficient delivery, cytotoxicity, and biodistribution in a mouse xenograft model of colorectal cancer. Both unmodified and modified chitosan nanoparticles showed enhanced accumulation at the tumor site. However, the modified chitosan nanoparticles showed considerably, less distribution in other organs. The relative gene expression as evaluated showed efficient delivery of PLK1-siRNA (0.5 mg/kg) with 50.7 ± 19.5% knockdown (P = 0.031) of PLK1 gene. The in vivo data reveals no systemic toxicity in the animals, when tested for systemic inflammation and liver toxicity. These results indicate a potential of using peptide-tagged nanoparticles for systemic delivery of siRNA at the targeted tumor site.

13.
Int J Nanomedicine ; 8: 2041-52, 2013.
Article in English | MEDLINE | ID: mdl-23723699

ABSTRACT

Recently, cell-penetrating peptides have been proposed to translocate antibodies, proteins, and other molecules in targeted drug delivery. The proposed study presents the synthesis and characterization of a peptide-based chitosan nanoparticle for small interfering RNA (siRNA) delivery, in-vitro. Specifically, the synthesis included polyethylene glycol (PEG), a hydrophilic polymer, and trans-activated transcription (TAT) peptide, which were chemically conjugated on the chitosan polymer. The conjugation was achieved using N-Hydroxysuccinimide-PEG-maleimide (heterobifunctional PEG) as a cross-linker, with the bifunctional PEG facilitating the amidation reaction through its N-Hydroxysuccinimide group and reacting with the amines on chitosan. At the other end of PEG, the maleimide group was chemically conjugated with the cysteine-modified TAT peptide. The degree of substitution on chitosan with PEG and on PEG with TAT was confirmed using colorimetric assays. The resultant polymer was used to form nanoparticles complexing siRNA, which were then characterized for particle size, morphology, cellular uptake, and cytotoxicity. The nanoparticles were tested in-vitro on mouse neuroblastoma cells (Neuro2a). Particle size and surface charge were characterized and an optimal pH condition and PEG molecular weight were determined to form sterically stable nanoparticles. Results indicate 7.5% of the amines in chitosan polymer were conjugated to the PEG and complete conjugation of TAT peptide was observed on the synthesized PEGylated chitosan polymer. Compared with unmodified chitosan nanoparticles, the nanoparticles formed at pH 6 were monodispersed and of <100 nm in size, exhibiting maximum cell transfection ability and very low cytotoxicity. Thus, this research may be of significance in translocating biotherapeutic molecules for intracellular delivery applications.


Subject(s)
Chitosan/chemistry , Drug Delivery Systems/methods , Nanoparticles/chemistry , RNA, Small Interfering/pharmacokinetics , Transfection/methods , tat Gene Products, Human Immunodeficiency Virus/chemistry , Animals , Cell Line, Tumor , Cell Survival/drug effects , Dithionitrobenzoic Acid , Hydrogen-Ion Concentration , Mice , Nanoparticles/toxicity , Particle Size , Polyethylene Glycols/chemistry , RNA, Small Interfering/chemistry , RNA, Small Interfering/genetics
14.
Expert Opin Drug Deliv ; 10(11): 1471-82, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23713443

ABSTRACT

OBJECTIVES: Oral health is influenced by the mouth's resident microorganisms. Dental caries and periodontitis are oral disorders caused by imbalances in the oral microbiota. Probiotics have potential for the prevention and treatment of oral disorders. Current formulations, including supplements and foods, have limitations for oral delivery including short storage time, low residence time in the mouth, effects on food consistency, and low patient compliance. Oral thin films (OTFs) may be efficient in delivering probiotics to the mouth. This research aims to develop a novel carboxymethyl cellulose (CMC)-probiotic-OTF to deliver probiotics for the treatment/prevention of oral disorders. METHODS: CMC-OTFs were developed with varying CMC concentration (1.25 - 10 mg/mL), weight (5 - 40 g), thickness (16 - 262 µm), hygroscopicity (30.8 - 78.9 mg/cm(2) film), and dissolving time (135 - 600 s). The 10 g 5 mg/mL CMC-OTF was selected and used to incorporate Lactobacillus fermentum NCIMB 5221 (6.75 × 10(8) cells/film), a probiotic with anti-inflammatory potential for periodontitis treatment and capable of inhibiting microorganisms responsible for dental caries and oral candidiasis. RESULTS: The CMC-OTF maintained probiotic viability and antioxidant activity following 150 days of storage with a production of 549.52 ± 26.08 µM Trolox equivalents. CONCLUSION: This research shows the successful development and characterization of a novel probiotic-CMC-OTF with potential as an oral health biotherapeutic.


Subject(s)
Carboxymethylcellulose Sodium/chemistry , Drug Delivery Systems , Limosilactobacillus fermentum , Probiotics/administration & dosage , Dental Caries/prevention & control , Humans , Mouth , Oral Health , Periodontitis/prevention & control
15.
J Pharm (Cairo) ; 2013: 103527, 2013.
Article in English | MEDLINE | ID: mdl-26555963

ABSTRACT

Microencapsulation is a technology that has shown significant promise in biotherapeutics, and other applications. It has been proven useful in the immobilization of drugs, live mammalian and bacterial cells and other cells, and other biopharmaceutics molecules, as it can provide material structuration, protection of the enclosed product, and controlled release of the encapsulated contents, all of which can ensure efficient and safe therapeutic effects. This paper is a comprehensive review of microencapsulation and its latest developments in the field. It provides a comprehensive overview of the technology and primary goals of microencapsulation and discusses various processes and techniques involved in microencapsulation including physical, chemical, physicochemical, and other methods involved. It also summarizes the state-of-the-art successes of microencapsulation, specifically with regard to the encapsulation of microorganisms, mammalian cells, drugs, and other biopharmaceutics in various diseases. The limitations and future directions of microencapsulation technologies are also discussed.

16.
J Pharm (Cairo) ; 2013: 812387, 2013.
Article in English | MEDLINE | ID: mdl-26555995

ABSTRACT

Neurodegeneration is characterized by progressive loss of structure and function of neurons. Several therapeutic methods and drugs are available to alleviate the symptoms of these diseases. The currently used delivery strategies such as implantation of catheters, intracarotid infusions, surgeries, and chemotherapies are invasive in nature and pose a greater risk of postsurgical complications, which can have fatal side effects. The current study utilizes a peptide (TAT and MGF) tagged PEGylated chitosan nanoparticle formulation for siRNA delivery, administered intranasally, which can bypass the blood brain barrier. The study investigates the optimal dose, duration, biodistribution, and toxicity, of the nanoparticle-siRNA formulation, in-vivo. The results indicate that 0.5 mg/kg of siRNA is delivered successfully to the hippocampus, thalamus, hypothalamus, and Purkinje cells in the cerebellum after 4 hrs of post intranasal delivery. The results indicate maximum delivery to the brain in comparison to other tissues with no cellular toxic effects. This study shows the potential of peptide-tagged PEGylated chitosan nanoparticles to be delivered intranasally and target brain tissue for the treatment of neurological disorders.

17.
Expert Opin Biol Ther ; 12(9): 1207-20, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22690730

ABSTRACT

INTRODUCTION: Oral health is affected by its resident microorganisms. Three prominent oral disorders are dental caries, gingivitis and periodontitis, with the oral microbiota playing a key role in the initiation/progression of all three. Understanding the microbiota and the diseases they may cause is critical to the development of new therapeutics. This review is focused on probiotics for the prevention and/or treatment of oral diseases. AREAS COVERED: This review describes the oral ecosystem and its correlation with oral health/disease. The pathogenesis and current prevention/treatment strategies of periodontal diseases (PD) and dental caries (DC) are depicted. An introduction of probiotics is followed by an analysis of their role in PD and DC, and their potential role(s) in oral health. Finally, a discussion ensues on the future research directions and limitations of probiotics for oral health. EXPERT OPINION: An effective oral probiotic formulation should contribute to the prevention/treatment of microbial diseases of the oral cavity. Understanding the oral microbiota's role in oral disease is important for the development of a therapeutic to prevent/treat dental diseases. However, investigations into clinical efficacy, delivery/dose optimization, mechanism(s) of action and other related parameters are yet to be fully explored. Keeping this in mind, investigations into oral probiotic therapies are proving promising.


Subject(s)
Dental Caries/therapy , Gingivitis/therapy , Mouth/microbiology , Oral Health , Periodontal Diseases/therapy , Probiotics/administration & dosage , Administration, Oral , Animals , Dental Caries/microbiology , Dental Caries/prevention & control , Gingivitis/microbiology , Gingivitis/prevention & control , Humans , Periodontal Diseases/microbiology , Periodontal Diseases/prevention & control , Treatment Outcome
18.
Pharmaceuticals (Basel) ; 5(2): 236-48, 2012 Feb 16.
Article in English | MEDLINE | ID: mdl-24288090

ABSTRACT

Probiotics possess potential therapeutic and preventative effects for various diseases and metabolic disorders. One important limitation for the oral delivery of probiotics is the harsh conditions of the upper gastrointestinal tract (GIT) which challenge bacterial viability and activity. One proposed method to surpass this obstacle is the use of microencapsulation to improve the delivery of bacterial cells to the lower GIT. The aim of this study is to use alginate-poly-L-lysine-alginate (APA) microcapsules to encapsulate Lactobacillus fermentum NCIMB 5221 and characterize its enzymatic activity and viability through a simulated GIT. This specific strain, in previous research, was characterized for its inherent ferulic acid esterase (FAE) activity which could prove beneficial in the development of a therapeutic for the treatment and prevention of cancers and metabolic disorders. Our findings demonstrate that the APA microcapsule does not slow the mass transfer of substrate into and that of the FA product out of the microcapsule, while also not impairing bacterial cell viability. The use of simulated gastrointestinal conditions led to a significant 2.5 log difference in viability between the free (1.10 × 104 ± 1.00 × 103 cfu/mL) and the microencapsulated (5.50 × 106 ± 1.00 × 105 cfu/mL) L. fermentum NCIMB 5221 following exposure. The work presented here suggests that APA microencapsulation can be used as an effective oral delivery method for L. fermentum NCIMB 5221, a FAE-active probiotic strain.

19.
J Biomed Biotechnol ; 2011: 981214, 2011.
Article in English | MEDLINE | ID: mdl-21772792

ABSTRACT

The gut microbiota plays a crucial role in maintaining health. Alterations of the gut bacterial population have been associated with a number of diseases. Past and recent studies suggest that one can positively modify the contents of the gut microbiota by introducing prebiotics, probiotics, synbiotics, and other therapeutics. This paper focuses on probiotic modulation of the gut microbiota by their delivery to the lower gastrointestinal tract (GIT). There are numerous obstacles to overcome before microorganisms can be utilized as therapeutics. One important limitation is the delivery of viable cells to the lower GIT without a significant loss of cell viability and metabolic features through the harsh conditions of the upper GIT. Microencapsulation has been shown to overcome this, with various types of microcapsules available for resolving this limitation. This paper discusses the gut microbiota and its role in disease, with a focus on microencapsulated probiotics and their potentials and limitations.


Subject(s)
Dietary Supplements , Drug Delivery Systems , Gastrointestinal Tract/microbiology , Drug Compounding , Humans , Lower Gastrointestinal Tract/microbiology
20.
Int J Nanomedicine ; 6: 485-94, 2011.
Article in English | MEDLINE | ID: mdl-21562608

ABSTRACT

Preparation of poly (ethylene glycol) (PEG)-grafted chitosan is essential for improving the biocompatibility and water solubility of chitosan. Presently available methods for this have limitations. This article describes a new method for preparing PEGylated chitosan nanoparticles. For this chitosan was chemoselectively modified using a novel scheme at the C6 position of its repeating units by PEG. The amine groups at the C2 position of the chitosan were protected using phthalic anhydride. Sodium hydride was used to catalyze the etherification reaction between chlorinated chitosan and methyl-PEG, and PEG-grafted chitosan was successfully synthesized. Each step was characterized using 13C nuclear magnetic resonance and Fourier transform infrared. After PEGylation the phthaloylated chitosan was successfully deprotected using hydrazine monohydrate. The synthetic scheme proposed demonstrates a new method for grafting PEG onto chitosan with a moderate degree of substitution. The potential of this polymer in nanoparticle preparation using an ionic gelation method and its gene delivery potentials were investigated by complexing a fluorescently labeled control siRNA. The result showed that suitable nanoparticles can be synthesized using this polymer and that they have capacity to carry genes and provide adequate transfection efficacy with no toxicity when tested in neuronal cells.


Subject(s)
Chitosan/chemistry , Drug Delivery Systems , Gene Transfer Techniques , Nanoparticles/chemistry , Polyethylene Glycols/chemical synthesis , Animals , Cell Line, Tumor , Cell Survival/drug effects , Electrophoretic Mobility Shift Assay , Membranes, Artificial , Mice , Microscopy, Electron, Transmission , Nanotechnology , Nuclear Magnetic Resonance, Biomolecular , Polyethylene Glycols/chemistry , Spectroscopy, Fourier Transform Infrared , Transfection/methods
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