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1.
Sci Rep ; 13(1): 20812, 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38012239

ABSTRACT

The conventional electrical grid faces significant issues, which this paper aims to address one of most of them using a proposed prototype of a smart microgrid energy management system. In addition to relying too heavily on fossil fuels, electricity theft is another great issue. The proposed energy management system can simultaneously detect electricity theft and implement demand response tactics by employing time-of-use pricing principles and comparing real electricity consumption with grid data. The system uses the Al-Biruni earth radius (BER) optimization algorithm to make smart choices about how to distribute the load, intending to reduce energy consumption and costs without sacrificing comfort. As a bonus, it considers limitations imposed by battery charging/discharging and decentralized power generation. Incorporating sensors and SCADA-based monitoring, the system provides accurate measurement and management of energy usage through load monitoring and control. An intuitive mobile app also helps consumers connect, allowing for more active participation and better control over energy use. Extensive field testing of the prototype shows that by moving loads from peak period to another off-peak period, electricity expenditures can be reduced by up to 48.45%. The energy theft value was calculated to be 1199 W, proving that the system's theft detection model was effective.

2.
Heliyon ; 9(7): e18044, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37483826

ABSTRACT

Ulvan is a polysaccharide from green algae that shows good hydrogel film dressing characteristics. Silver nanoparticles (AgNP) can be incorporated into the hydrogel film to improve antibacterial properties and provide a potential burn treatment. In this study, we developed a novel hydrogel film wound dressing composed of ulvan and silver nanoparticles. Two concentrations (0.5 mM and 1 mM) of silver nitrate were used to produce ulvan-silver nanoparticles hydrogel film (UHF-AgNP0.5 and UHF-AgNP1), respectively. The physicochemical characteristics of the hydrogel films were evaluated, including particle size, zeta potential, Fourier transform infrared (FTIR), X-ray diffractometry (XRD), scanning electron microscope and energy-dispersive X-ray (SEM-EDX). Furthermore, the in vitro antimicrobial activity, and second-degree burn wound healing test were evaluated. The UHF-AgNP0.5 showed the highest antimicrobial activity compared to UHF-AgNP1 and UHF film. Meanwhile, an in vivo study using Wistar rats induced second-degree burns showed that UHF-AgNP0.5 significantly accelerated the healing process by regulating the inflammatory process, increasing re-epithelialization, and improving the vascularization process. Ulvan-silver nanoparticle hydrogel films have the ability to accelerate the healing of second-degree burns and are potential candidates for wound dressings.

3.
JAMA Otolaryngol Head Neck Surg ; 149(7): 580-586, 2023 07 01.
Article in English | MEDLINE | ID: mdl-37166815

ABSTRACT

Importance: Determining interventions to manage obstructive sleep apnea (OSA) depends on clinical examination, polysomnography (PSG) results, and imaging analysis. There remains the need of a noninvasive and cost-effective way to correlate relevant upper airway anatomy with severity of OSA to direct treatment and optimize outcome. Objective: To determine whether backscattered ultrasonographic imaging (BUI) analysis of the tongue is associated with severity of OSA in adults. Design, Setting, and Participants: In this prospective, single-center, diagnostic study of a consecutive series of patients (aged ≥18 years) at a sleep surgery clinic, the 89 included patients had a PSG within 3 years at the time of ultrasonography and BUI analysis between July 2020 and March 2022. Patients were excluded if body mass index had changed more than 10% since time of PSG. A standardized submental ultrasonographic scan with laser alignment was used with B-mode and BUI analysis applied to the tongue. The B-mode and BUI intensity were associated with the apnea-hypopnea index (AHI), a measure of severity of apnea from normal (no OSA) to severe OSA. Exposures: Ultrasonography and PSG. Main Outcomes and Measures: The main outcomes were BUI parameters and their association with AHI value. Results: Eighty-nine patients were included between July 2020 and March 2022. A total of 70 (78.7%) male patients were included; and distribution by race and ethnicity was 46 (52%) White participants, 22 (25%) Asian participants, and 2 (2%) African American participants, and 19 (21%) others. Median (IQR) age was 37.0 (29.0-48.3) years; median (IQR) BMI was 25.3 (23.2-29.8); and median (IQR) AHI was 11.1 (5.6-23.1) events per hour. At the middle to posterior tongue region, the 4 OSA severity levels explained a significant portion of the BUI variance (η2 = 0.153-0.236), and a significant difference in BUI values was found between the subgroups with AHI values of less than 15 (no OSA and mild OSA) and greater than or equal to 15 (moderate OSA and severe OSA) events per hour. The echo intensity showed no significant differences. The BUI values showed a positive association with AHI, with a Spearman correlation coefficient of up to 0.43. Higher BUI values remained associated with higher AHI after correction for the covariates of BMI and age. Conclusions and Relevance: In this prospective diagnostic study, standardized BUI analysis of the tongue was associated with OSA severity. With the practicality of ultrasonography, this analysis is pivotal in connecting anatomy with physiology in treatment planning for patients with OSA.


Subject(s)
Sleep Apnea, Obstructive , Humans , Adult , Male , Adolescent , Middle Aged , Female , Prospective Studies , Sleep Apnea, Obstructive/diagnosis , Sleep/physiology , Polysomnography/methods , Tongue/diagnostic imaging
4.
Drug Des Devel Ther ; 15: 4071-4089, 2021.
Article in English | MEDLINE | ID: mdl-34616142

ABSTRACT

Recurrent aphthous stomatitis (RAS) is a disease marked by painful oral lesions on the buccal and labial mucosa or tongue. Drug delivery systems (DDS) for RAS include topical forms that manage wound healing, cover the ulcer, and relieve the associated pain. DDS targeting the oral mucosa face a major challenge, especially the short residence times in the mouth due to the effect of "saliva wash-out", which continually removes the drug. The objective of this review is to study the development of preparation forms and delivery systems of various types and preparations that have been used for RAS management from 1965 until February 2020. There are 20 types of DDS for RAS which were discussed in 62 articles. The preparations were classified into 4 preparation forms: liquid, semi-solid, solid, and miscellaneous. In addition, the ultimate DDS for RAS preparations is the semi-solid forms (41.94%), which include 5 types of DDS are gel, paste, patch, cream, and ointment. This preparation was developed into new preparation form (11.29%), such as adhesive alginates, dentifrice, OraDisc, membranes, bioresorbable plates, pellicles, and gelosomes. Generally, the mucosal drug delivery system is the method of choice in RAS treatment because the ulcer is commonly located in the oral mucosa. In conclusion, these preparations are designed to improve drug delivery and drug activity for the treatment of RAS ulcers. Moreover, almost all of these DDS are topical preparations that use various types of mucoadhesive polymers to increase both residence time in the oral mucosa and pain relief in RAS treatment.


Subject(s)
Drug Delivery Systems , Stomatitis, Aphthous/drug therapy , Animals , Humans , Mouth Mucosa/pathology , Stomatitis, Aphthous/pathology , Tongue/pathology
5.
Molecules ; 26(1)2021 Jan 03.
Article in English | MEDLINE | ID: mdl-33401558

ABSTRACT

Pulicaria jaubertii is a medicinal herb that alleviates inflammations and fever. Chromatographic separation, phytochemical characterization, and in vitro biological activities of the plant n-hexane extract were conducted for the first time in this study. Six compounds were isolated for the first time from the n-hexane fraction of Pulicaria jaubertii aerial parts and were identified on the bases of NMR and MS analyses as pseudo-taraxaterol (1), pseudo-taraxasterol acetate (2), 3ß-acetoxytaraxaster-20-en-30-aldehyde (3), calenduladiol-3-O-palmitate (4), stigmasterol (5), and α-tocospiro B (6). Compound (6) was a rare tocopherol-related compound and was isolated for the first time from family Asteraceae, while compound (3) was isolated for the first time from genus Pulicaria. The total alcoholic extract and n-hexane fraction were tested for their anti-inflammatory, antidiabetic, and cytotoxic activities. The n-hexane fraction has dose dependent red blood cells (RBCs) membrane stabilization and inhibition of histamine release activities with IC50: 60.8 and 72.9 µg/mL, respectively. As antidiabetic activity, the alcoholic extract exerted the most inhibition on the activity of yeast α-glucosidase, with an IC50: 76.8 µg/mL. The n-hexane fraction showed cytotoxic activity against hepatocarcinoma (HepG-2), breast carcinoma (MCF-7), and prostate carcinoma (PC-3) cell lines with IC50: 51.8, 90.8 and 62.2 µg/mL, respectively. In conclusion, the anti-inflammatory effect of Pulicaria jaubertii might be attributed to the triterpenoid constituents of the n-hexane extract of the plant.


Subject(s)
Anti-Inflammatory Agents , Antineoplastic Agents, Phytogenic , Hypoglycemic Agents , Neoplasms/drug therapy , Plants, Edible/chemistry , Pulicaria/chemistry , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacokinetics , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Cytotoxins/chemistry , Cytotoxins/pharmacology , Hep G2 Cells , Humans , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/pharmacology , MCF-7 Cells , Neoplasms/metabolism , PC-3 Cells , Rats , U937 Cells
6.
J Clin Tuberc Other Mycobact Dis ; 17: 100120, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31788562

ABSTRACT

BACKGROUND: Isoniazid (INH) is the mainstay antimicrobial in the treatment of tuberculosis (TB). It is acetlylated in the liver to acetyl-INH. However, there is variation in rate of acetylation of INH among TB patients (i.e. fast, intermediate or slow acetylators) which impacts on the treatment outcomes. AIM: The isoniazid acetylation phenotypes in the expatriate Sudanese population were determined to provide future guidance since TB is prevalent in Sudan. METHODS: A community-based trial among Sudanese expatriates in Saudi Arabia was undertaken to identify INH-acetylation phenotypes. After overnight fasting, a single dose of 200 mg of INH was given to the volunteers. Three hours later, 5 ml of blood were drawn from each volunteer and prepared for High-Performance Liquid Chromatography (HPLC) analysis. The main outcomes were INH and Acetyl-INH concentrations in plasma and the subsequent Acetyl-INH/INH metabolic ratio (MR). RESULTS: The findings suggest that slow acetylation is highly prevalent among the study participants (n = 43; 84.31%). Moreover, there was no statistically significant correlation between age and the MR (r = -0.18, P = 0.20). Further, there was no significant association between gender and the MR (P = 0.124). Similarly, no significant association was found between smoking habits and MR (P = 0.24). CONCLUSION: Isoniazid phenotyping suggests predominantly slow acetylation among the Sudanese in this sample. The study found no statistically significant associations between the MR and age or gender or smoking.

7.
Pharmacogn Mag ; 12(47): 165-70, 2016.
Article in English | MEDLINE | ID: mdl-27601844

ABSTRACT

BACKGROUND: Many plants growing in Saudi Arabia are used in folk medicine for treatment of several diseases. OBJECTIVE: Information of the chemical constituents and biological activities of plants is desirable for the discovery of therapeutic agents and discovering the actual value of folkloric remedies. MATERIALS AND METHODS: The compounds were isolated and purified using silica gel column chromatography and preparative high-performance liquid chromatography-diode array detector (HPLC-DAD) Method. The alcoholic extracts of these plants were evaluated for biological activities. RESULTS: Isolation and characterization of 1-feruloyl-ß-D-glucopyranoside (1) as well as new secondary metabolite tryptophan methyl ester (2) were isolated for the 1(st) time from the Horwoodia dicksoniae. The three flavones were isolated from Rumex cyprius identified as isoorientin (3), vitexin (4), and Cynarosid (5). The structures of these compounds were characterized by nuclear magnetic resonance and mass spectrometry analysis and comparing with literature. The compounds were isolated and purified using silica gel column chromatography and preparative HPLC-DAD Method. The alcoholic extracts of these plants were evaluated for antimicrobial activities against two Gram-positive bacteria, two Gram-negative bacteria, and four pathogenic fungi. Both plants showed good activities against Syncephalastrum racemosum and Streptococcus pneumoniae with minimal inhibitory concentrations (MICs) 0.98 and 1.95 µg/mL, respectively. H. dicksoniae showed good activity against Aspergillus fumigates with an MIC 1.95 µg/mL. The two extracts showed also effective free radical scavenging activities in the 1,1-diphenyl-2-picrylhydrazyl assay. H. dicksoniae exhibited remarkable cytotoxic activity against Human breast cancer mammary cancer cells-7, Human liver cancer human hepatoma carcinoma cells-2, and human lung carcinoma (A-549) cell lines. CONCLUSIONS: It was suggested that further work should be carried out to isolate, purify, and characterize the active constituents responsible for the activity of these plants. SUMMARY: New secondary metabolite Tryptophane methyl ester as well as 1-feruloyl-ß-D-glucopyranoside were isolated for the first time from the HD.Isoorientin, vitexin and Cynarosid were isolated from RC.HD exhibited good activity against Aspergillus fumigates with an MIC 1.95 µg mL(-1).HD showed significant cytotoxic activity against Human breast cancer (MCF-7), Human liver cancer (HepG-2) and Human lung carcinoma (A-549) cell lines.

8.
PLoS One ; 10(4): e0119316, 2015.
Article in English | MEDLINE | ID: mdl-25848768

ABSTRACT

Dietary and metabolic therapies are increasingly being considered for a variety of neurological disorders, based in part on growing evidence for the neuroprotective properties of the ketogenic diet (KD) and ketones. Earlier, we demonstrated that ketones afford hippocampal synaptic protection against exogenous oxidative stress, but the mechanisms underlying these actions remain unclear. Recent studies have shown that ketones may modulate neuronal firing through interactions with ATP-sensitive potassium (KATP) channels. Here, we used a combination of electrophysiological, pharmacological, and biochemical assays to determine whether hippocampal synaptic protection by ketones is a consequence of KATP channel activation. Ketones dose-dependently reversed oxidative impairment of hippocampal synaptic integrity, neuronal viability, and bioenergetic capacity, and this action was mirrored by the KATP channel activator diazoxide. Inhibition of KATP channels reversed ketone-evoked hippocampal protection, and genetic ablation of the inwardly rectifying K+ channel subunit Kir6.2, a critical component of KATP channels, partially negated the synaptic protection afforded by ketones. This partial protection was completely reversed by co-application of the KATP blocker, 5-hydoxydecanoate (5HD). We conclude that, under conditions of oxidative injury, ketones induce synaptic protection in part through activation of KATP channels.


Subject(s)
Hippocampus/drug effects , Ion Channel Gating/drug effects , KATP Channels/metabolism , Ketones/pharmacology , Long-Term Potentiation/drug effects , Neuronal Plasticity/drug effects , Potassium Channels, Inwardly Rectifying/physiology , Adenosine Triphosphate/metabolism , Animals , Hippocampus/metabolism , Hydrogen Peroxide/toxicity , Mice , Mice, Knockout , Mitochondria/drug effects , Mitochondria/metabolism , Neuroprotective Agents/pharmacology , Oxidants/toxicity , Patch-Clamp Techniques , Rats , Rats, Sprague-Dawley , Sulfonylurea Receptors/metabolism
9.
Neurosurg Focus ; 36(2): E12, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24484250

ABSTRACT

OBJECT: For patients with glioblastoma multiforme, median survival time is approximately 14 months. Longer progression-free and overall survival times correlate with gross-total resection of tumor. The ability to identify tumor cells intraoperatively could result in an increased percentage of tumor resected and thus increased patient survival times. Available labeling methods rely on metabolic activity of tumor cells; thus, they are more robust in high-grade tumors, and their utility in low-grade tumors and metastatic tumors is not clear. The authors demonstrate intraoperative identification of tumor cells by using labeled tumor-specific antibodies. METHODS: GL261 mouse glioma cells exhibit high expression of a membrane-bound protein called second tyrosinase-related protein (TRP-2). The authors used these cells to establish an intracranial, immunocompetent model of malignant glioma. Antibodies to TRP-2 were labeled by using Alexa Fluor 488 fluorescent dye and injected into the tail vein of albino C57BL/6 mice. After 24 hours, a craniotomy was performed and the tissue was examined in vivo by using an Optiscan 5.1 handheld portable confocal fiber-optic microscope. Tissue was examined ex vivo by using a Pascal 5 scanning confocal microscope. RESULTS: Labeled tumor cells were visible in vivo and ex vivo under the respective microscopes. CONCLUSIONS: Fluorescently labeled tumor-specific antibodies are capable of binding and identifying tumor cells in vivo, accurately and specifically. The development of labeled markers for the identification of brain tumors will facilitate the use of intraoperative fluorescence microscopy as a tool for increasing the extent of resection of a broad variety of intracranial tumors.


Subject(s)
Antibodies, Neoplasm , Brain Neoplasms/diagnosis , Fluorescent Dyes , Glioma/diagnosis , Intramolecular Oxidoreductases , Animals , Antibodies, Neoplasm/metabolism , Brain Neoplasms/immunology , Brain Neoplasms/metabolism , Cell Line, Tumor , Fluorescent Dyes/metabolism , Glioma/immunology , Glioma/metabolism , Intramolecular Oxidoreductases/immunology , Intramolecular Oxidoreductases/metabolism , Mice , Mice, Inbred C57BL , Microscopy, Confocal/methods
10.
Neurosurg Focus ; 36(2): E16, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24484254

ABSTRACT

OBJECT: The authors sought to assess the feasibility of a handheld visible-wavelength confocal endomicroscope imaging system (Optiscan 5.1, Optiscan Pty., Ltd.) using a variety of rapid-acting fluorophores to provide histological information on gliomas, tumor margins, and normal brain in animal models. METHODS: Mice (n = 25) implanted with GL261 cells were used to image fluorescein sodium (FNa), 5-aminolevulinic acid (5-ALA), acridine orange (AO), acriflavine (AF), and cresyl violet (CV). A U251 glioma xenograft model in rats (n = 5) was used to image sulforhodamine 101 (SR101). A swine (n = 3) model with AO was used to identify confocal features of normal brain. Images of normal brain, obvious tumor, and peritumoral zones were collected using the handheld confocal endomicroscope. Histological samples were acquired through biopsies from matched imaging areas. Samples were visualized with a benchtop confocal microscope. Histopathological features in corresponding confocal images and photomicrographs of H & E-stained tissues were reviewed. RESULTS: Fluorescence induced by FNa, 5-ALA, AO, AF, CV, and SR101 and detected with the confocal endomicroscope allowed interpretation of histological features. Confocal endomicroscopy revealed satellite tumor cells within peritumoral tissue, a definitive tumor border, and striking fluorescent cellular and subcellular structures. Fluorescence in various tumor regions correlated with standard histology and known tissue architecture. Characteristic features of different areas of normal brain were identified as well. CONCLUSIONS: Confocal endomicroscopy provided rapid histological information precisely related to the site of microscopic imaging with imaging characteristics of cells related to the unique labeling features of the fluorophores. Although experimental with further clinical trial validation required, these data suggest that intraoperative confocal imaging can help to distinguish normal brain from tumor and tumor margin and may have application in improving intraoperative decisions during resection of brain tumors.


Subject(s)
Brain Neoplasms/diagnosis , Brain/pathology , Computers, Handheld , Disease Models, Animal , Fluorescent Dyes , Glioma/diagnosis , Animals , Brain/metabolism , Brain Neoplasms/metabolism , Female , Glioma/metabolism , Mice , Mice, Inbred C57BL , Microscopy, Confocal/methods , Rats , Swine
11.
PLoS One ; 8(2): e57495, 2013.
Article in English | MEDLINE | ID: mdl-23469004

ABSTRACT

Cigarette smoke exposure markedly compromises the ability of the immune system to protect against invading pathogens and tumorigenesis. Nicotine is a psychoactive component of tobacco products that acts as does the natural neurotransmitter, acetylcholine, on nicotinic receptors (nAChRs). Here we demonstrate that natural killer (NK) cells strongly express nAChR ß2. Nicotine exposure impairs the ability of NK cells to kill target cells and release cytokines, a process that is largely abrogated by nAChR ß2 deficiency. Further, nicotinic suppression of NF-κB-induced transcriptional activity in NK cells is dependent on nAChR ß2. This nAChR subtype also plays a large role in the NK cell-mediated control of melanoma lung metastasis, in a murine lung metastasis model exposed to nicotine. Our findings suggest nAChR ß2 as a prominent pathway for nicotine induced impairment of NK cell functions which contributes to the occurrence of smoking-related pathologies.


Subject(s)
Disease Models, Animal , Killer Cells, Natural/physiology , Lung Neoplasms/pathology , Neoplasm Metastasis , Receptors, Nicotinic/physiology , Animals , Base Sequence , DNA Primers , Female , Melanoma, Experimental/pathology , Mice , Mice, Inbred C57BL , Nicotine/pharmacology , Reverse Transcriptase Polymerase Chain Reaction
12.
Cancer Manag Res ; 4: 309-23, 2012.
Article in English | MEDLINE | ID: mdl-23049280

ABSTRACT

OBJECTIVES: Immunotherapy with immunostimulants is an attractive therapy against gliomas. C-type lectin receptors specific for galactose/N-acetylgalactosamine (GCLR) regulate cellular differentiation, recognition, and trafficking of monocyte-derived cells. A peptide mimetic of GCLR ligands (GCLRP) was used to activate blood monocytes and populations of myeloid-derived cells against a murine glioblastoma. METHODS: The ability of GCLRP to stimulate phagocytosis by human microglia and monocyte-derived cells of the brain (MDCB) isolated from a human glioblastoma was initially assessed in vitro. Induction of activation markers on blood monocytes was assayed by flow cytometry after administration of GCLRP to naive mice. C57BL/6 mice underwent stereotactic intracranial implantation of GL261 glioma cells and were randomized for tumor size by magnetic resonance imaging, which was also used to assess increase in tumor size. Brain tumor tissues were analyzed using flow cytometry, histology, and enzyme-linked immunosorbent assay with respect to tumor, peritumoral area, and contralateral hemisphere regions. RESULTS: GCLRP exhibited strong stimulatory effect on MDCBs and blood monocytes in vitro and in vivo. GCLRP was associated with an increased percentage of precursors of dendritic cells in the blood (P = 0.003), which differentiated into patrolling macrophages in tumoral (P = 0.001) and peritumoral areas (P = 0.04), rather than into dendritic cells, as in control animals. Treatment with GCLRP did not result in a significant change in survival of mice bearing a tumor. CONCLUSIONS: In vitro and in vivo activation of monocytes was achieved by administration of GCLR to mice. GCLRP-activated blood monocytes were recruited to the brain and exhibited specific phenotypes corresponding with tumor region (glioma, peritumoral zone, and contralateral glioma-free hemisphere). GCLRP treatment alone was associated with increased glioma mass as the result of the infiltration of phagocytic cells. Regional specificity for MDCB may have significant tumor treatment implications.

13.
Cancer Manag Res ; 4: 325-34, 2012.
Article in English | MEDLINE | ID: mdl-23049281

ABSTRACT

BACKGROUND: A peptide mimetic of a ligand for the galactose/N-acetylgalactosamine-specific C-type lectin receptors (GCLR) exhibited monocyte-stimulating activity, but did not extend survival when applied alone against a syngeneic murine malignant glioma. In this study, the combined effect of GCLRP with radiation was investigated. METHODS: C57BL/6 mice underwent stereotactic intracranial implantation of GL261 glioma cells. Animals were grouped based on randomized tumor size by magnetic resonance imaging on day seven. One group that received cranial radiation (4 Gy on days seven and nine) only were compared with animals treated with radiation and GCLRP (4 Gy on days seven and nine combined with subcutaneous injection of 1 nmol/g on alternative days beginning on day seven). Magnetic resonance imaging was used to assess tumor growth and correlated with survival rate. Blood and brain tissues were analyzed with regard to tumor and contralateral hemisphere using fluorescence-activated cell sorting analysis, histology, and enzyme-linked immunosorbent assay. RESULTS: GCLRP activated peripheral monocytes and was associated with increased blood precursors of dendritic cells. Mean survival increased (P < 0.001) and tumor size was smaller (P < 0.02) in the GCLRP + radiation group compared to the radiation-only group. Accumulation of dendritic cells in both the tumoral hemisphere (P < 0.005) and contralateral tumor-free hemisphere (P < 0.01) was associated with treatment. CONCLUSION: Specific populations of monocyte-derived brain cells develop critical relationships with malignant gliomas. The biological effect of GCLRP in combination with radiation may be more successful because of the damage incurred by tumor cells by radiation and the enhanced or preserved presentation of tumor cell antigens by GCLRP-activated immune cells. Monocyte-derived brain cells may be important targets for creating effective immunological modalities such as employing the receptor system described in this study.

14.
PLoS One ; 7(5): e36197, 2012.
Article in English | MEDLINE | ID: mdl-22563484

ABSTRACT

INTRODUCTION: The ketogenic diet (KD) is a high-fat, low-carbohydrate diet that alters metabolism by increasing the level of ketone bodies in the blood. KetoCal® (KC) is a nutritionally complete, commercially available 4:1 (fat:carbohydrate+protein) ketogenic formula that is an effective non-pharmacologic treatment for the management of refractory pediatric epilepsy. Diet-induced ketosis causes changes to brain homeostasis that have potential for the treatment of other neurological diseases such as malignant gliomas. METHODS: We used an intracranial bioluminescent mouse model of malignant glioma. Following implantation animals were maintained on standard diet (SD) or KC. The mice received 2×4 Gy of whole brain radiation and tumor growth was followed by in vivo imaging. RESULTS: Animals fed KC had elevated levels of ß-hydroxybutyrate (p = 0.0173) and an increased median survival of approximately 5 days relative to animals maintained on SD. KC plus radiation treatment were more than additive, and in 9 of 11 irradiated animals maintained on KC the bioluminescent signal from the tumor cells diminished below the level of detection (p<0.0001). Animals were switched to SD 101 days after implantation and no signs of tumor recurrence were seen for over 200 days. CONCLUSIONS: KC significantly enhances the anti-tumor effect of radiation. This suggests that cellular metabolic alterations induced through KC may be useful as an adjuvant to the current standard of care for the treatment of human malignant gliomas.


Subject(s)
Diet, Ketogenic , Glioma/diet therapy , Glioma/radiotherapy , 3-Hydroxybutyric Acid/metabolism , Animals , Blood Glucose/metabolism , Brain/metabolism , Brain/pathology , Combined Modality Therapy , Disease Models, Animal , Humans , Kaplan-Meier Estimate , Ketones/blood , Mice , Mice, Inbred C57BL , Neoplasm Transplantation , Time Factors
15.
Epilepsy Res ; 100(3): 327-37, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22019313

ABSTRACT

Seizures, particularly first onset seizures in adults, are a diagnostic hallmark of brain tumors (Giglio and Villano, 2010). Unfortunately, malignant brain tumors are almost uniformly fatal due, in part, to the limitations of available therapies. Improvement in the survival of brain cancer patients requires the design of new therapeutic modalities including those that enhance currently available therapies. One potential strategy is to exploit differences in metabolic regulation between normal cells and tumor cells through dietary approaches. Previous studies have shown that a high-fat, low-carbohydrate ketogenic diet (KD) extends survival in animal models of glioma; however, the mechanism for this effect is not entirely known. We examined the effects of an experimental KD on a mouse model of glioma, and compared patterns of gene expression in tumors versus contralateral non-tumor containing brain from animals fed either a KD or a standard diet. We found that the KD reduced reactive oxygen species (ROS) production in tumor cells. Gene expression profiling demonstrated that the KD induces an overall reversion to expression patterns seen in non-tumor specimens, and a number of genes involved in modulating ROS levels and oxidative stress were altered in tumor cells. In addition, there was reduced expression of genes involved in signal transduction from growth factors known to be involved in glioma growth. These results suggest that the anti-tumor effect of the KD is multifactorial, and elucidation of genes whose expression is altered will help identify mechanisms through which ketones inhibit tumor growth, reduce seizure activity and provide neuroprotection.


Subject(s)
Brain Neoplasms/diet therapy , Brain Neoplasms/genetics , Diet, Ketogenic , Glioma/diet therapy , Glioma/genetics , Animals , Disease Models, Animal , Gene Expression Profiling , Humans , Reactive Oxygen Species/metabolism
16.
J Vis Exp ; (57): e3403, 2011 Nov 06.
Article in English | MEDLINE | ID: mdl-22158303

ABSTRACT

The mouse glioma 261 (GL261) is recognized as an in vivo model system that recapitulates many of the features of human glioblastoma multiforme (GBM). The cell line was originally induced by intracranial injection of 3-methyl-cholantrene into a C57BL/6 syngeneic mouse strain (1); therefore, immunologically competent C57BL/6 mice can be used. While we use GL261, the following protocol can be used for the implantation and monitoring of any intracranial mouse tumor model. GL261 cells were engineered to stably express firefly luciferase (GL261-luc). We also created the brighter GL261-luc2 cell line by stable transfection of the luc2 gene expressed from the CMV promoter. C57BL/6-cBrd/cBrd/Cr mice (albino variant of C57BL/6) from the National Cancer Institute, Frederick, MD were used to eliminate the light attenuation caused by black skin and fur. With the use of albino C57BL/6 mice; in vivo imaging using the IVIS Spectrum in vivo imaging system is possible from the day of implantation (Caliper Life Sciences, Hopkinton, MA). The GL261-luc and GL261-luc2 cell lines showed the same in vivo behavior as the parental GL261 cells. Some of the shared histological features present in human GBMs and this mouse model include: tumor necrosis, pseudopalisades, neovascularization, invasion, hypercellularity, and inflammation (1). Prior to implantation animals were anesthetized by an intraperitoneal injection of ketamine (50 mg/kg), xylazine (5 mg/kg) and buprenorphine (0.05 mg/kg), placed in a stereotactic apparatus and an incision was made with a scalpel over the cranial midline. A burrhole was made 0.1 mm posterior to the bregma and 2.3mm to the right of the midline. A needle was inserted to a depth of 3mm and withdrawn 0.4 mm to a depth of 2.6 mm. Two µl of GL261-luc or GL261-luc2 cells (10(7) cells/ml) were infused over the course of 3 minutes. The burrhole was closed with bonewax and the incision was sutured. Following stereotactic implantation the bioluminescent cells are detectable from the day of implantation and the tumor can be analyzed using the 3D image reconstruction feature of the IVIS Spectrum instrument. Animals receive a subcutaneous injection of 150 µg luciferin /kg body weight 20 min prior to imaging. Tumor burden is quantified using mean tumor bioluminescence over time. Tumor-bearing mice were observed daily to assess morbidity and were euthanized when one or more of the following symptoms are present: lethargy, failure to ambulate, hunched posture, failure to groom, anorexia resulting in >10% loss of weight. Tumors were evident in all of the animals on necropsy.


Subject(s)
Brain Neoplasms/pathology , Glioma/pathology , Luminescent Measurements/methods , Animals , Cell Line, Tumor , Disease Models, Animal , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Mice , Mice, Inbred C57BL , Neoplasm Transplantation
17.
J Neurosurg ; 115(6): 1131-8, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21923240

ABSTRACT

OBJECT: Infiltrative tumor resection is based on regional (macroscopic) imaging identification of tumorous tissue and the attempt to delineate invasive tumor margins in macroscopically normal-appearing tissue, while preserving normal brain tissue. The authors tested miniaturized confocal fiberoptic endomicroscopy by using a near-infrared (NIR) imaging system with indocyanine green (ICG) as an in vivo tool to identify infiltrating glioblastoma cells and tumor margins. METHODS: Thirty mice underwent craniectomy and imaging in vivo 14 days after implantation with GL261-luc cells. A 0.4 mg/kg injection of ICG was administered intravenously. The NIR images of normal brain, obvious tumor, and peritumoral zones were collected using the handheld confocal endomicroscope probe. Histological samples were acquired from matching imaged areas for correlation of tissue images. RESULTS: In vivo NIR wavelength confocal endomicroscopy with ICG detects fluorescence of tumor cells. The NIR and ICG macroscopic imaging performed using a surgical microscope correlated generally to tumor and peritumor regions, but NIR confocal endomicroscopy performed using ICG revealed individual tumor cells and satellites within peritumoral tissue; a definitive tumor border; and striking fluorescent microvascular, cellular, and subcellular structures (for example, mitoses, nuclei) in various tumor regions correlating with standard clinical histological features and known tissue architecture. CONCLUSIONS: Macroscopic fluorescence was effective for gross tumor detection, but NIR confocal endomicroscopy performed using ICG enhanced sensitivity of tumor detection, providing real-time true microscopic histological information precisely related to the site of imaging. This first-time use of such NIR technology to detect cancer suggests that combined macroscopic and microscopic in vivo ICG imaging could allow interactive identification of microscopic tumor cell infiltration into the brain, substantially improving intraoperative decisions.


Subject(s)
Brain Neoplasms/pathology , Brain Neoplasms/surgery , Glioblastoma/pathology , Glioblastoma/surgery , Indocyanine Green , Infrared Rays , Animals , Biopsy , Cerebral Angiography/instrumentation , Cerebral Angiography/methods , Coloring Agents , Craniotomy , Disease Models, Animal , Female , Intraoperative Period , Mice , Mice, Inbred C57BL , Microscopy, Confocal/instrumentation , Microscopy, Confocal/methods , Microscopy, Video/instrumentation , Microscopy, Video/methods , Miniaturization
18.
Nutr Metab (Lond) ; 7: 74, 2010 Sep 10.
Article in English | MEDLINE | ID: mdl-20831808

ABSTRACT

BACKGROUND: Malignant brain tumors affect people of all ages and are the second leading cause of cancer deaths in children. While current treatments are effective and improve survival, there remains a substantial need for more efficacious therapeutic modalities. The ketogenic diet (KD) - a high-fat, low-carbohydrate treatment for medically refractory epilepsy - has been suggested as an alternative strategy to inhibit tumor growth by altering intrinsic metabolism, especially by inducing glycopenia. METHODS: Here, we examined the effects of an experimental KD on a mouse model of glioma, and compared patterns of gene expression in tumors vs. normal brain from animals fed either a KD or a standard diet. RESULTS: Animals received intracranial injections of bioluminescent GL261-luc cells and tumor growth was followed in vivo. KD treatment significantly reduced the rate of tumor growth and prolonged survival. Further, the KD reduced reactive oxygen species (ROS) production in tumor cells. Gene expression profiling demonstrated that the KD induces an overall reversion to expression patterns seen in non-tumor specimens. Notably, genes involved in modulating ROS levels and oxidative stress were altered, including those encoding cyclooxygenase 2, glutathione peroxidases 3 and 7, and periredoxin 4. CONCLUSIONS: Our data demonstrate that the KD improves survivability in our mouse model of glioma, and suggests that the mechanisms accounting for this protective effect likely involve complex alterations in cellular metabolism beyond simply a reduction in glucose.

19.
Neurosurgery ; 66(2): 410-7; discussion 417-8, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20087141

ABSTRACT

INTRODUCTION: Recent developments in optical science and image processing have miniaturized the components required for confocal microscopy. Clinical confocal imaging applications have emerged, including assessment of colonic mucosal dysplasia during colonoscopy. We present our initial experience with handheld, miniaturized confocal imaging in a murine brain tumor model. METHODS: Twelve C57/BL6 mice were implanted intracranially with 10(5) GL261 glioblastoma cells. The brains of 6 anesthetized mice each at 14 and 21 days after implantation were exposed surgically, and the brain surface was imaged using a handheld confocal probe affixed to a stereotactic frame. The probe was moved systematically over regions of normal and tumor-containing tissue. Intravenous fluorescein and topical acriflavine contrast agents were used. Biopsies were obtained at each imaging site beneath the probe and assessed histologically. Mice were killed after imaging. RESULTS: Handheld confocal imaging produced exquisite images, well-correlated with corresponding histologic sections, of cellular shape and tissue architecture in murine brain infiltrated by glial neoplasm. Reproducible patterns of cortical vasculature, as well as normal gray and white matter, were identified. Imaging effectively distinguished between tumor and nontumor tissue, including infiltrative tumor margins. Margins were easily identified by observers without prior neuropathology training after minimum experience with the technology. CONCLUSION: Miniaturized handheld confocal imaging may assist neurosurgeons in detecting infiltrative brain tumor margins during surgery. It may help to avoid sampling error during biopsy of heterogeneous glial neoplasms, with the potential to supplement conventional intraoperative frozen section pathology. Clinical trials are warranted on the basis of these promising initial results.


Subject(s)
Brain Neoplasms/surgery , Glioblastoma/surgery , Hand , Microscopy, Confocal/methods , Neurosurgery/methods , Animals , Brain Neoplasms/pathology , Cell Line, Tumor , Disease Models, Animal , Ergonomics , Female , Glioblastoma/pathology , Humans , Image Processing, Computer-Assisted , Mice , Mice, Inbred C57BL , Optical Fibers
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