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1.  Surface plasmon resonance-induced photoactivation of gold nanoparticles as bactericidal agents against methicillin-resistant Staphylococcus aureus 
Systemic infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and other bacteria are responsible for millions of deaths worldwide, and much of this mortality is due to the rise of antibiotic-resistant organisms as a result of natural selection. Gold nanoparticles synthesized using the standard wet chemical procedure were photoexcited using an 808 nm 2 W laser diode and further administered to MRSA bacteria. Flow cytometry, transmission electron microscopy, contrast phase microscopy, and fluorescence microscopy combined with immunochemical staining were used to examine the interaction of the photoexcited gold nano-particles with MRSA bacteria. We show here that phonon–phonon interactions following laser photoexcitation of gold nanoparticles exhibit increased MRSA necrotic rates at low concentrations and short incubation times compared with MRSA treated with gold nanoparticles alone. These unique data may represent a step forward in the study of bactericidal effects of various nanomaterials, with applications in biology and medicine.
doi:10.2147/IJN.S54950
PMCID: PMC3968082  PMID: 24711697
MRSA; SPR; multi-drug resistant bacteria; infection; gold nanoparticles; laser
2.  Photothermal Treatment of Human Pancreatic Cancer Using PEGylated Multi-Walled Carbon Nanotubes Induces Apoptosis by Triggering Mitochondrial Membrane Depolarization Mechanism 
Journal of Cancer  2014;5(8):679-688.
Pancreatic cancer (PC) is one of the most lethal solid tumor in humans, with an overall 5-year survival rate of less than 5%. Thermally active carbon nanotubes have already brought to light promising results in PC research and treatment.
We report here the construct of a nano-biosystem based on multi-walled carbon nanotubes and polyethylene glycol (PEG) molecules validated through AFM, UV-Vis and DLS. We next studied the photothermal effect of these PEG-ylated multi-walled carbon nanotubes (5, 10 and 50 μg/mL, respectively) on pancreatic cancer cells (PANC-1) and further analyzed the molecular and cellular events involved in cell death occurrence. Using cell proliferation, apoptosis, membrane polarization and oxidative stress assays for ELISA, fluorescence microscopy and flow cytometry we show here that hyperthermia following MWCNTs-PEG laser mediated treatment (808 nm, 2W) leads to mitochondrial membrane depolarization that activates the flux of free radicals within the cell and the oxidative state mediate cellular damage in PC cells via apoptotic pathway. Our results are of decisive importance especially in regard with the development of novel nano-biosystems capable to target mitochondria and to synergically act both as cytotoxic drug as well as thermally active agents in order to overcome one of the most common problem met in oncology, that of intrinsic resistance to chemotherapeutics.
doi:10.7150/jca.9481
PMCID: PMC4174512  PMID: 25258649
carbon nanotubes; pancreatic cancer; PEG functionalization; photothermal ablation; apoptosis; mitochondrial therapy.
3.  Nicotinamide-functionalized multiwalled carbon nanotubes increase insulin production in pancreatic beta cells via MIF pathway 
Recent data in the literature support the role of nicotinamide (NA) as a pharmacologic agent that stimulates pancreatic beta-cells to produce insulin in vitro. There are data showing that carbon nanotubes may be useful in initiating and maintaining cellular metabolic responses. This study shows that administration of multiwalled carbon nanotubes (MWCNTs) functionalized with nicotinamide (NA-MWCNTs) leads to significant insulin production compared with individual administration of NA, MWCNTs, and a control solution. Treatment of 1.4E7 cells for 30 minutes with NA-MWCNTs at concentrations ranging from 1 mg/L to 20 mg/L resulted in significantly increased insulin release (0.18 ± 0.026 ng/mL for 1 mg/L, 0.21 ± 0.024 ng/mL for 5 mg/L, and 0.27 ± 0.028 ng/mL for 20 mg/L). Thus, compared with cells treated with NA only (0.1 ± 0.01 ng/mL for 1 mg/L, 0.12 ± 0.017 ng/mL for 5 mg/L, and 0.17 ± 0.01 ng/mL for 20 mg/L) we observed a significant positive effect on insulin release in cells treated with NA-MWCNTs. The results were confirmed using flow cytometry, epifluorescence microscopy combined with immunochemistry staining, and enzyme-linked immunosorbent assay techniques. In addition, using immunofluorescence microscopy techniques, we were able to demonstrate that MWCNTs enhance insulin production via the macrophage migration inhibitory factor pathway. The application and potential of NA combined with MWCNTs as an antidiabetic agent may represent the beginning of a new chapter in the nanomediated treatment of diabetes mellitus.
doi:10.2147/IJN.S48223
PMCID: PMC3770514  PMID: 24039418
carbon nanotubes; NA; insulin-producing cells; insulin; macrophage migration inhibitory factor; diabetes mellitus
4.  Choice of anesthetic technique on plasma concentrations of interleukins and cell adhesion molecules 
Background
Whether inflammatory responses to surgery are comparably activated during total intravenous anesthesia (TIVA) and during volatile anesthesia remains unclear. We thus compared the perioperative effects of TIVA and isoflurane anesthesia on plasma concentrations of proinflammatory and anti-inflammatory interleukins and cell adhesion molecules.
Methods
Patients having laparoscopic cholecystectomies were randomly allocated to two groups: 44 were assigned to TIVA and 44 to isoflurane anesthesia. IL-1β, IL-6, IL-8, IL-10, IL-13, and the cellular adhesion molecules intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 were determined preoperatively, before incision, and at 2 and 24 hours postoperatively. Our primary outcomes were area-under-the-curve cytokine and adhesion molecule concentrations over 24 postoperative hours.
Results
The only statistically significant difference in area-under-the-curve concentrations was for IL-6, which was greater in patients given isoflurane:78 (95% confidence interval (CI): 52 to 109) pg/ml versus 33 (22 to 50) pg/ml, P= 0.006. Two hours after surgery, IL-6 was significantly greater than baseline in patients assigned to isoflurane: 47 (95% CI: 4 to 216, P<0.001) pg/ml versus 18 (95%CI: 4 to 374, P<0.001) pg/ml in the TIVA group. In contrast, IL-10 was significantly greater in patients assigned to TIVA: 20 (95% CI: 2 to 140, P<0.001) pg/ml versus 12 (95% CI: 3 to 126, P<0.001) pg/ml. By 24 hours after surgery, concentrations were generally similar between study groups and similar to baseline values.
Conclusion
The only biomarker whose postoperative area-under-the-curve concentrations differed significantly as a function of anesthetic management was IL-6. Two hours after surgery, IL-6 concentrations were significantly greater in patients given isoflurane than TIVA. However, the differences were modest and seem unlikely to prove clinically important. Further studies are needed.
doi:10.1186/2047-0525-2-8
PMCID: PMC3964335  PMID: 24472144
Inhalation anesthetics; Intravenous anesthetics; Propofol; Cell adhesion molecules; Interleukins
5.  The Effects of a Small Dose of Dexamethasone on Cell Adhesion Molecules during Laparoscopic Cholecystectomy 
Drugs in R&d  2012;11(4):309-316.
Background and Objective: There are only a few publications on the effects of dexamethasone on the plasma levels of cell adhesion molecules (CAMs). The goal of this study was to investigate the effects of dexamethasone 4mg on the perioperative plasma levels of CAMs (soluble intercellular adhesion molecules [sICAM-1] and soluble vascular cell adhesion molecules [sVCAM-1]) during laparoscopic cholecystectomy.
Methods: Forty-two patients undergoing laparoscopic cholecystectomy under total intravenous anesthesia were enrolled and randomly divided into two groups: the first group received dexamethasone 4mg (DEX group, n = 21) and the second group were controls (C group, n = 21). Plasma levels of sICAM-1 and sVCAM-1 were assessed before anesthesia, after induction (before surgery), and at 2 and 24 hours after surgery, respectively. Comparisons were performed for area under the plasma concentration-time curve (AUC) and within-group values.
Results: AUC comparison for sICAM-1 showed significantly increased levels in the C group (p = 0.036), while there was no significant difference for sVCAM-1 (p = 0.052). Within-group analysis showed increased levels for both sICAM-1 and sVCAM-1 in the C group at 24 hours postoperatively (p = 0.35 and p = 0.025, respectively).
Conclusions: In our study, dexamethasone 4mg given before laparoscopic cholecystectomy determined a significant decrease in plasma levels of sICAM-1. Both sICAM-1 and sVCAM-1 remained increased compared with baseline at 24 hours in the C group. This may partially explain the postoperative antiinflammatory effects of dexamethasone. Further studies are needed.
doi:10.2165/11590460-000000000-00000
PMCID: PMC3585831  PMID: 21877762
6.  The Effects of a Small Dose of Dexamethasone on Cell Adhesion Molecules during Laparoscopic Cholecystectomy 
Drugs in R&D  2012;11(4):309-316.
Background and Objective: There are only a few publications on the effects of dexamethasone on the plasma levels of cell adhesion molecules (CAMs). The goal of this study was to investigate the effects of dexamethasone 4mg on the perioperative plasma levels of CAMs (soluble intercellular adhesion molecules [sICAM-1] and soluble vascular cell adhesion molecules [sVCAM-1]) during laparoscopic cholecystectomy.
Methods: Forty-two patients undergoing laparoscopic cholecystectomy under total intravenous anesthesia were enrolled and randomly divided into two groups: the first group received dexamethasone 4mg (DEX group, n = 21) and the second group were controls (C group, n = 21). Plasma levels of sICAM-1 and sVCAM-1 were assessed before anesthesia, after induction (before surgery), and at 2 and 24 hours after surgery, respectively. Comparisons were performed for area under the plasma concentration-time curve (AUC) and within-group values.
Results: AUC comparison for sICAM-1 showed significantly increased levels in the C group (p = 0.036), while there was no significant difference for sVCAM-1 (p = 0.052). Within-group analysis showed increased levels for both sICAM-1 and sVCAM-1 in the C group at 24 hours postoperatively (p = 0.35 and p = 0.025, respectively).
Conclusions: In our study, dexamethasone 4mg given before laparoscopic cholecystectomy determined a significant decrease in plasma levels of sICAM-1. Both sICAM-1 and sVCAM-1 remained increased compared with baseline at 24 hours in the C group. This may partially explain the postoperative antiinflammatory effects of dexamethasone. Further studies are needed.
doi:10.2165/11590460-000000000-00000
PMCID: PMC3585831  PMID: 21877762
7.  Ethinylestradiol30μg-drospirenone and metformin: could this combination improve endothelial dysfunction in polycystic ovary syndrome? 
Background
We are hereby investigating for the first time the effect of the association ethinylestradiol30μg-drospirenone 3mg (DRP/EE30μg) plus metformin and weight loss on endothelial status and C-reactive protein (hsCRP) levels in polycystic ovary syndrome (PCOS).
Methods
25 young women with PCOS (mean age 22.76 ± 0.83 years, body mass index (BMI): 28.44 ± 6.23) who completed the study were prospectively evaluated. The oral contraceptive- DRP/EE30μg (21 days/month) and metformin (1700 mg daily) were administered for 6 months to the PCOS group. Additionally, the 15 overweight and obese patients (BMI > 25 kg/m2) were instructed in a diet of no more than 1500 cal daily. Primary outcome measures were surrogate markers of cardiovascular disease and included endothelial function, i.e. flow-mediated dilatation (FMD) on the brachial artery and endothelin-1 levels, as well as hsCRP concentrations, body composition (measured by whole-body dual-energy X-ray-absorptiometry) and insulin resistance. Variables were assessed at baseline, as well as after our medical intervention.
Results
The combination between DRP/EE30μg plus metformin combined with weight loss triggered a significant improvement in the FMD values (FMD-PCOSbasal 3.48 ± 1.00 vs FMD-PCOS6 months7.43 ± 1.04, p = 0.033), as well as body composition and insulin insensitivity (p < 0.05). Regarding hsCRP levels, there was no significant intragroup (PCOS6months – PCOSbasal) difference.
Conclusion
A 6-month course of metformin- DRP/EE30μg (associated with weight loss) improves the endothelial dysfunction in PCOS and shows neutral effects on hsCRP concentrations as an inflammation marker. These data demand for reevaluation of the medical therapy in PCOS, particularly in women with additional metabolic and cardiovascular risk factors (ClinicalTrials.gov Identifier: NCT01459445).
doi:10.1186/1472-6823-12-9
PMCID: PMC3413550  PMID: 22713099
Ethinylestradiol30μg-drospirenone; Flow-mediated dilatation; Endothelial dysfunction; HsCRP; Metformin; Polycystic ovary syndrome
8.  Influence of nanomaterials on stem cell differentiation: designing an appropriate nanobiointerface 
During the last decade, due to advances in functionalization chemistry, novel nanobiomaterials with applications in tissue engineering and regenerative medicine have been developed. These novel materials with their unique physical and chemical properties are bioactive hierarchical structures that hold great promise for future development of human tissues. Thus, various nanomaterials are currently being intensively explored in the directed differentiation of stem cells, the design of novel bioactive scaffolds, and new research avenues towards tissue regeneration. This paper illustrates the latest achievements in the applications of nanotechnology in tissue engineering in the field of regenerative medicine.
doi:10.2147/IJN.S29975
PMCID: PMC3356220  PMID: 22619557
nanotechnology; nanomaterials; tissue engineering; regeneration; stem cell differentiation
9.  Effective colon cancer prophylaxis in mice using embryonic stem cells and carbon nanotubes 
Introduction
In recent years, a new concept of an anticancer vaccine has been proposed to prevent and control the proliferation and expansion of cancer cells by eliciting an immune boost in biological systems. The recent literature supports the role of embryonic stem cells (ESC) as cellular agents that stimulate the biological systems to destroy cancer cells. However, at present, a true anticancer vaccine remains elusive. There are several lines of evidence showing that carbon nanotubes may be used to initiate and maintain immune responses.
Objective
The authors proposed to test the therapeutic potential of multiwalled carbon nanotubes (MWCNTs) combined with ESC as agents to induce an immune boost and provide subsequent anticancer protection in mice.
Methods
C57 BL/6 mice were immunized with ESC and MWCNTs.
Results
The proposed vaccine led to significant antitumor responses and enhanced tumor rejection in mice with subcutaneous inoculation of MC38 colon malign cells compared with groups only administered ESC, only MWCNTs, and controls.
Conclusion
The application and potential of ESC combined with MWCNTs as anticancer immunization agents may represent the beginning of a new chapter in the treatment of colon cancer.
doi:10.2147/IJN.S24060
PMCID: PMC3181055  PMID: 21976971
carbon nanotubes; embryonic stem cells; synergistic enhancement; immunization; colon cancer; vaccine
10.  Selective ex-vivo photothermal ablation of human pancreatic cancer with albumin functionalized multiwalled carbon nanotubes 
The process of laser-mediated ablation of cancer cells marked with biofunctionalized carbon nanotubes is frequently called “nanophotothermolysis”. We herein present a method of selective nanophotothermolisys of pancreatic cancer (PC) using multiwalled carbon nanotubes (MWCNTs) functionalized with human serum albumin (HSA). With the purpose of testing the therapeutic value of these nanobioconjugates, we have developed an ex-vivo experimental platform. Surgically resected specimens from patients with PC were preserved in a cold medium and kept alive via intra-arterial perfusion. Additionally, the HSA-MWCNTs have been intra-arterially administered in the greater pancreatic artery under ultrasound guidance. Confocal and transmission electron microscopy combined with immunohistochemical staining have confirmed the selective accumulation of HSA-MWCNTs inside the human PC tissue. The external laser irradiation of the specimen has significantly produced extensive necrosis of the malign tissue after the intra-arterial administration of HSA-MWCNTs, without any harmful effects on the surrounding healthy parenchyma. We have obtained a selective photothermal ablation of the malign tissue based on the selective internalization of MWCNTs with HSA cargo inside the pancreatic adenocarcinoma after the ex-vivo intra-arterial perfusion.
doi:10.2147/IJN.S19013
PMCID: PMC3124855  PMID: 21720504
noncovalent functionalization; irradiation; tumor; malignant; MWCNTs
11.  Enhanced laser thermal ablation for the in vitro treatment of liver cancer by specific delivery of multiwalled carbon nanotubes functionalized with human serum albumin 
The main goal of this investigation was to develop and test a new method of treatment for human hepatocellular carcinoma (HCC). We present a method of carbon nanotube-enhanced laser thermal ablation of HepG2 cells (human hepatocellular liver carcinoma cell line) based on a simple multiwalled carbon nanotube (MWCNT) carrier system, such as human serum albumin (HSA), and demonstrate its selective therapeutic efficacy compared with normal hepatocyte cells. Both HepG2 cells and hepatocytes were treated with HSA–MWCNTs at various concentrations and at various incubation times and further irradiated using a 2 W, 808 nm laser beam. Transmission electron, phase contrast, and confocal microscopy combined with immunochemical staining were used to demonstrate the selective internalization of HSA–MWCNTs via Gp60 receptors and the caveolin-mediated endocytosis inside HepG2 cells. The postirradiation apoptotic rate of HepG2 cells treated with HSA–MWCNTs ranged from 88.24% (for 50 mg/L) at 60 sec to 92.34% (for 50 mg/L) at 30 min. Significantly lower necrotic rates were obtained when human hepatocytes were treated with HSA–MWCNTs in a similar manner. Our results clearly show that HSA–MWCNTs selectively attach on the albondin (aka Gp60) receptor located on the HepG2 membrane, followed by an uptake through a caveolin-dependent endocytosis process. These unique results may represent a major step in liver cancer treatment using nanolocalized thermal ablation by laser heating.
doi:10.2147/IJN.S15841
PMCID: PMC3026578  PMID: 21289990
carbon nanotubes; albumin; HepG2 cells; noncovalent functionalization; laser irradiation; Gp60 receptor

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