Scholar : ΛΟΓΟΣ - νέα αποτελέσματα

Reactions of Hydroxyl Radicals with Oxygenated Hydrocarbons in the Gas Phase: A Laser Photolysis/Laser-Induced Fluorescence Study

C Bänsch - 2017

Page 1. Cornelie B¨ansch Reactions of Hydroxyl Radicals with oxygenated
Hydrocarbons in the Gas Phase: A Laser Photolysis / Laser-Induced Fluorescence
Study λογος Page 2. Page 3. Reactions of Hydroxyl Radicals with …

Zur Interaktion von Filmkühlung und Heißgasströmung auf konturierten Turbinenseitenwänden

J Kneer - 2017

… Dr.-Ing. Hans-J¨org Bauer Johannes Kneer Zur Interaktion von Filmk¨uhlung und
Heißgasstr¨omung auf konturierten Turbinenseitenw¨anden Experimentelle Untersuchungen
zu W¨arme¨ubergang und Filmk¨uhleffektivit¨at Band 69/2017 λογος Page 2. Page 3 …

Macht das (historischen) Sinn?: Narrative Strukturen von Schülern vor und nach der De-Konstruktion eines geschichtlichen Spielfilms

B Wehen

… Narrative Strukturen von Schülern vor und nach der De-Konstruktion eines geschichtlichen
Spielfilms λογος Page 2. Page 3 … Narrative Strukturen von Sch¨ulern vor und nach der
De-Konstruktion eines geschichtlichen Spielfilms Logos Verlag Berlin λογος Page 6. Zugl …

[PDF] Beyond Cross-Cultural Philosophy: Towards a New Enlightenment

D Quintern - مجله پژوهشهای فلسفی دانشگاه تبریز, 2017‎

… The term logos reveals its belonging to a philosophical tra- dition, which is embedded in a
Christian Weltanschaung (world view) and is clearly reflected in the prologue of the gospel of
John: „In the beginning was the Word (λόγος), and the Word was with God, and the Word was …

ALEXANDRE D'APHRODISE ET LE PREMIER MOTEUR COMME PRINCIPE

G Guyomarc'h - Les principes cosmologiques du platonisme

… Alexandre transforme le ποιοῦν du Portique en ποιητικόν et le λόγος en ἔνυλον εἶδος. Or le
choix de ces termes par les stoïciens n'est déjà sans doute pas ano- din. Pourquoi donc cette
réécriture du λόγος en εἶδος, dont Alexandre semble être au surplus le premier auteur …

AUGUSTINIAN THOUGHT IN ALCUIN'S WRITING: A PHILOLOGICAL-HISTORICAL APPROACH

SC Moesch - History of Political Thought, 2018

… In all the texts under investigation, Christian doc- trine plays an essential role. Since,
according to scriptures,34 the 'word' (λόγος) is divine, Christian texts from the
beginning placed emphasis on the meaning and origin of words …

[PDF] Mariano Escolástico, APl 201. Una interpretación de Eros en el reinado de Justino II y Sofia

CA Martins de Jesus - Cuadernos de Filología Clásica. Estudios griegos e …, 2017

… They are, in Platonic moral, the attributes of a good city and a wise-good man, as in the Republic
427e (δῆλον δὴ ὅτι ϲοφή τ' ἐϲτὶ καὶ 18 De adoratione et culto in spiritu et veritate 68.709:
ϲαφήϲ ϲοι καὶ ἀποχρῶν εἰϲ εὐμαθίαν ὁ λόγοϲ; 19 Eg Resp …

LES PRINCIPES PHYSIQUES STOÏCIENS À LA LUMIÈRE DE LEURS CRITIQUES ANTIQUES

B Collette-Dučić - Les principes cosmologiques du platonisme

Page 91. LES PRINCIPES PHYSIQUES STOÏCIENS À LA LUMIÈRE DE LEURS CRITIQUES
ANTIQUES Bernard Collette-Dučić (Université Laval)* La bassesse de cette doctrine sera
révélée plus manifestement après l'exposé des idées de Platon …

QU'EST-CE QU'UN PRINCIPE SELON ARISTOTE?

S Delcomminette - Les principes cosmologiques du platonisme

… ne peut y avoir de définition négative. 9 L'expression «définition nominale» est fondée
sur l'expression λόγος ἕτερος ὀνοματώδης que l'on trouve en Seconds analytiques,
II, 10, 93 b 30-31. Comme le fait re- marquer WD Ross …

 

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Scholar : intitle:laryngeal - new results

Three-dimensional imaging assessment of anatomic invasion and volumetric considerations for chemo/radiotherapy-based laryngeal preservation in T3 larynx cancer

M Kamal, SP Ng, SA Eraj, CD Rock, B Pham… - Oral Oncology, 2018

Objectives To investigate the impact of 3-Diminsional (3D) tumor volume (TV) and extent of
involvement of primary tumor on treatment outcomes in a large uniform cohort of T3
laryngeal carcinoma patients treated with nonsurgical laryngeal preservation strategies.

[HTML] Laryngeal cleft—case series from a surgical neonatal intensive care unit

C Jorgensen, A Trivedi, A Cheng, J De Lima, K Walker - Australian Journal of …, 2018

Background: Laryngeal clefts are rare congenital anomalies of the upper aerodigestive tract
with a persistent connection between the posterior laryngotracheal airway and the
oesophagus. The purpose of this study was to review the clinical presentation, management

Feasibility of Salvage Selective Neck Dissection after Primary Irradiation of Pharyngeal and Laryngeal Carcinoma

NM Lazim, K Abdullah, B Karakullukcu, B Tan - ORL, 2018

… Original Paper. Feasibility of Salvage Selective Neck Dissection after Primary Irradiation of
Pharyngeal and Laryngeal Carcinoma. Mat Lazim N. a · Abdullah K. b · Karakullukcu B. c · Tan
IB c … Result: A total of 29 NDs were analyzed. In 17 neck sides, viable metastases were found (58%),

[PDF] The laryngeal adductor reflex is a new methodology for monitoring thyroid surgeries that may predict long term outcome of vocal fold function

MÁ Sánchez-Roldán, MJ Téllez, CF Sinclair, S Ulkatan

Sasaki CT, Jassin B, Kim YH, Hundal J, Rosenblatt W, Ross DA. Central facilitation of the glottic
closure reflex in humans. Ann Otol Rhinol Laryngol 2003;112:293–297 … Sinclair CF, Téllez
MJ, Tapia OR, Ulkatan S, Deletis V. A novel methodology for assessing laryngeal and vagus

 

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Scholar : Decannulation - νέα αποτελέσματα

Safety of Chest Physiotherapy for Acute Respiratory Distress Syndrome during Venovenous Extracorporeal Membrane Oxygenation: A Case Report

TH Wang, CP Wu, LY Wang, SF Lee - 物理治療, 2017

… The parameters used to evaluate safety of CPT while the case was on VV ECMO included
occurrences of adverse events (ie, arrhythmia, ventricular tachycardia, cardiac arrest, bleeding,
and removal of endotracheal tube or unplanned decannulation) and vital sign changes …

 

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Scholar : ΜΕΝΙΕΡΕ - νέα αποτελέσματα

[HTML] Vbn diagnose i nevrologik klinikk. Hva er vertebro-basilær insuffisiens?

AVC PRKamchatnov, BB VALi

… skilles fra: meniere sykdom; labyrinthitis; neurinom av den auditive nerve; multippel
sklerose; vestibulær nevronitt; positiv godartet svimmelhet; psykiske lidelser; cervikal
svimmelhet; hydrocephalus; senil hørselstap. Bare en …

 

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Scholar : Laryngomalacia - νέα αποτελέσματα

[HTML] Upper airway obstruction in neonates: Does sleep exacerbate symptoms?

T Van Heest, B Ebert, BB Roby, J Sidman - Laryngoscope Investigative Otolaryngology

… Results: In patients with laryngomalacia (n5 31), 41.9% worsened with agitation, 38.7% worsened
with feeding, 16.1% worsened with positioning, 0.0% worsened during sleep, and 25.8% had
no aggravating factors … Aggravating factors in laryngomalacia are vari- able …

 

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Scholar : Laryngotracheal reconstruction - νέα αποτελ

[HTML] Laryngeal cleft—case series from a surgical neonatal intensive care unit

C Jorgensen, A Trivedi, A Cheng, J De Lima, K Walker - Australian Journal of …, 2018

… upper aero-digestive tract in which a persistent connection between the posterior laryngotracheal
airway and … Laryngeal cleft is a rare anomaly which was first successfully surgically reconstructed
and a … infants in our series with type III cleft had an open reconstruction, with the …

Evaluation of decellularized xenogenic porcine auricular cartilage as a novel biocompatible filler

SC Shin, HY Park, N Shin, DW Jung, HK Kwon, JM Kim… - Journal of Biomedical Materials …

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Scholar : Undersea "Hyperbaric Medicine" - νέα αποτελέσματα

[HTML] Effects of the Ketogenic diet in overweight divers breathing Enriched Air Nitrox

G Bosco, A Rizzato, S Quartesan, E Camporesi… - Scientific Reports, 2018

… Samples from six overweight divers (mean ± SD, age: 55.2 ± 4.96 years; BMI: 26.7 ± 0.86
kg/m 2 ) were obtained a) before and after a dive breathing Enriched Air Nitrox and performing
20-minute mild underwater exercise, b) after a dive (same conditions) performed after 7 days …

 

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Necrotizing infection of the heart

Publication date: September–October 2018
Source:Clinical Imaging, Volume 51
Author(s): David H. Ballard, George Patton Pennington, George P. Pennington, Joe Johnson, Sanjeev Bhalla, Constantine Raptis
A case of necrotizing infection of the heart is presented. A 70-year-old woman presented with vague chest and abdominal pain. CT of the abdomen and pelvis was initially obtained, which demonstrated gas in the myocardium of the left ventricle. Subsequent chest CT, endoscopy, and abdominal surgical exploration did not reveal perforated viscus or diaphragm compromise. At median sternotomy, the inferior wall of the heart was found to be necrotic. Culture of the excised tissue grew E. coli. The patient expired shortly after surgical exploration.



http://ift.tt/2EId0qg

Simplified Bernoulli formula to predict flow limiting stenosis at coronary computed tomography angiography

Publication date: September–October 2018
Source:Clinical Imaging, Volume 51
Author(s): Nobuo Tomizawa, Kodai Yamamoto, Shinichi Inoh, Takeshi Nojo, Sunao Nakamura
ObjectiveTo compare the diagnostic performance of estimated energy loss (EEL) with diameter stenosis (DS) to estimate significant stenosis by fractional flow reserve (FFR).Materials and methodsOne hundred twenty-five patients were included. EEL was calculated using DS, lesion length, minimal lumen area and left ventricular volume. FFR ≤ 0.80 was determined significant.ResultsEEL improved the accuracy from 63% (95% confidence interval (CI): 55–72%) to 83% (95% CI: 75–89%, p < 0.0001). EEL increased the area under the receiver operating characteristics curve from 0.63 to 0.85 (p < 0.0001).ConclusionsEEL improved the diagnostic performance to detect functionally significant stenosis than DS.



http://ift.tt/2o7UWvu

Cardiac autonomic responses to nociceptive stimuli in patients with chronic disorders of consciousness

Publication date: Available online 14 February 2018
Source:Clinical Neurophysiology
Author(s): Eleonora Tobaldini, Edgar Toschi-Dias, Pietro Davide Trimarchi, Nicola Brena, Angela Comanducci, Silvia Casarotto, Nicola Montano, Guya Devalle
ObjectivesPatients with chronic disorders of consciousness (DOC) may show alterations of autonomic function; however, in this clinical population, no data are available on the specific effects of nociceptive stimuli on cardiac autonomic control. Thus, we aimed at investigating the effects of a noxious stimulation on heart rate variability (HRV) in a population of patients with chronic DOC, taking into account different states of consciousness (vegetative state/unresponsive wakefulness syndrome, VS/UWS and minimally conscious state, MCS).MethodsWe enrolled twenty-four DOC patients (VS/UWS, n=12 and MCS, n=12). ECG and respiration were recorded during baseline, immediately after the nociceptive stimulus and, finally, during the recovery period. Linear and nonlinear HRV measures were used to evaluate the cardiac autonomic control.ResultsIn DOC patients, nonlinear HRV analysis showed that nociceptive stimuli are able to elicit a change of autonomic function characterized by an increased sympathetic and a reduced vagal modulation. A significant reduction of autonomic complexity has also been detected. More interestingly, VS/UWS patients showed a less complex dynamics compared to MCS patients.ConclusionsCardiac autonomic responses are able to significantly differentiate the autonomic function between VS/UWS and MCS patients.SignificanceNonlinear HRV analysis may represent a useful tool to characterize the cardiac autonomic responses to nociceptive stimuli in a chronic DOC population.



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Isaacs syndrome: a slow potassium channelopathy caused by autoantibodies?

Publication date: Available online 15 February 2018
Source:Clinical Neurophysiology
Author(s): Tomoko Nakazato, Yukiko Tsuji, Kazuaki Kanai, Yu-ichi Noto, Yasunobu Hoshino, Kazuo Yamashiro, Kazumasa Yokoyama, Kenya Nishioka, Yasushi Shimo, Osamu Watanabe, Toshiki Mizuno, Nobutaka Hattori




http://ift.tt/2oaqUqS

Effective Antimicrobial Stewardship Strategies for Cost-Effective Utilization of Telavancin for the Treatment of Patients With Hospital-Acquired Bacterial Pneumonia Caused by Staphylococcus aureus

Publication date: Available online 15 February 2018
Source:Clinical Therapeutics
Author(s): James A. McKinnell, Shelby Corman, Dipen Patel, Grace H. Leung, Lynne M. Gordon, Thomas P. Lodise
PurposeClinicians and stewardship programs are challenged with positioning of novel, higher priced antibiotic agents for the treatment of clinical infections. We developed a decision-analytic model to describe costs, including drug, total treatment costs, and health care outcomes, associated with telavancin (TLV) compared with vancomycin (VAN) for patients with Staphylococcus aureus (SA) hospital-acquired bacterial pneumonia (HABP).MethodsThis decision-analytic model assessed the treatment of SA-HABP with TLV versus VAN. Data were obtained from the ATTAIN (Assessment of Telavancin for Treatment of Hospital-Acquired Pneumonia) clinical trials on the following: the probability of clinical cure; probability of nephrotoxicity; and prevalence of polymicrobial infection (30%), methicillin-resistant Staphylococcus aureus (MRSA) (68%), and SA with VAN MIC ≥1 µg/mL (85%). Data on length of stay for cure (10 days), failure (10 additional days), and nephrotoxicity (3.5 days) were based on literature. Cost per treated patient and incremental cost-effectiveness ratio (ICER) per additional cure were calculated for SA-HABP and for monomicrobial SA-HABP. One-way sensitivity analyses were performed.FindingsPatients with SA-HABP were sub-grouped by methicillin susceptibility (n = 140, 32%) or resistance (n = 293, 68%), and occurrence of polymicrobial (n = 128, 30%) vs monomicrobial (n = 305, 70%) infections. Under the base case, hospital cost for patients with HABP treated with TLV was $42,564 and with VAN, it was $42,296. Telavancin was associated with higher drug ($2082) and nephrotoxicity ($467) costs and lower intensive care unit (−$1738) and ventilator (−$114) costs. ICER was $4156 per additional cure. ICER was sensitive to probabilities of cure, length of treatment in cures, intensive care unit cost, TLV cost, and additional length of stay due to failure. For monomicrobial SA-HABP, TLV was associated with a net cost savings of $907 per patient and yielded economic dominance.ImplicationsOur decision-analytic model suggests that TLV for monomicrobial SA-HABP is associated with higher drug acquisition costs but a favorable ICER relative to VAN, provided that effective antimicrobial stewardship limits therapy to 7 days. Sensitivity analyses suggest a potential economic benefit of TLV treatment with appropriate patient selection. Antimicrobial stewardship programs may be able to reduce total costs through judicious use of novel antimicrobial agents. ClinicalTrials.gov identifiers: NCT00107952 and NCT00124020.



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Iron-engineered mesoporous silica nanocatalyst with biodegradable and catalytic framework for tumor-specific therapy

Publication date: May 2018
Source:Biomaterials, Volume 163
Author(s): Liying Wang, Minfeng Huo, Yu Chen, Jianlin Shi
Inorganic mesoporous silica-based nanovehicles are highly promising for drug delivery but still suffer from the disadvantages of lacking functionality and poor biodegradability on account of the inert silica framework. Moreover, conventional cancer therapeutics typically employ toxic anticancer drugs or invasive external irradiations, which will inevitably give rise to severe adverse effects and diminished therapeutic outcome. In this work, we report on the iron engineered framework of mesoporous silica nanoparticles (MSNs) to fabricate a nanocatalyst with biodegradable and catalytic framework via a "dissolution-regeneration" strategy (designated as rFeOx-HMSN). Based on the abundant overexpressed hydrogen peroxide (H2O2) and mild acidic nature in tumor microenvironment (TME), rFeOx-HMSN nanocatalyst could trigger in-situ Fenton-like reactions to produce highly toxic hydroxyl radicals (·OH), causing remarkable oxidative damages against tumor cells/xenografts. Additionally, the iron-engineered rFeOx-HMSN nanocatalyst could readily collapse via an iron-extraction strategy under protein-rich environment, thereby improving the biodegradability of rFeOx-HMSN nanocatalyst. This work paves a promising way to engineer the inert framework of MSN into functional, biodegradable and catalytic nanoplatform, featuring effective tumor-therapeutic outcome and stimuli-responsive biodegradation concurrently.

Graphical abstract

http://ift.tt/2svaUpb

Reduction-sensitive fluorescence enhanced polymeric prodrug nanoparticles for combinational photothermal-chemotherapy

Publication date: May 2018
Source:Biomaterials, Volume 163
Author(s): Yuanyuan Zhang, Dan Yang, Hongzhong Chen, Wei Qi Lim, Fiona Soo Zeng Phua, Guanghui An, Piaoping Yang, Yanli Zhao
In this study, a reduction-sensitive supramolecular polymeric drug delivery system was developed for combinational photothermal-chemotherapy of cancer. The multifunctional system was self-assembled by specific host–guest interactions between hydrophilic β-cyclodextrin functionalized hyaluronic acid and adamantane linked camptothecin/dye conjugate, where a near-infrared (NIR) absorbing dye IR825 was loaded. The hydrophilic hyaluronic acid shell endows the assembly with excellent colloidal stability and biocompatibility. The embedded disulfide bond in the camptothecin/dye conjugate was cleaved under reducing environment, leading to the release of the conjugated drug and the recovery of fluorescence emission. Meanwhile, the dye IR825 could efficiently transfer the absorbed light into local heat, making the nanoplatform an effective system for photothermal therapy. As evident by confocal microscopy images, the nanoplatform was quickly internalized by HeLa, MCF-7, and U14 cancer cells and released drug molecules inside the cells. In vitro cell viability assays confirmed that the cancer cells were efficiently killed by the treatment of the nanoplatform under NIR light irradiation. Significant tumor regression was also observed in the tumor-bearing mice upon the administration of the nanoplatform through combinational photothermal-chemotherapy therapy. Hence, this nanoplatform presented a great potential in site-specific combined photothermal-chemotherapy of tumor.

Graphical abstract

http://ift.tt/2o0mrI9

Cyclic cRGDfk peptide and Chlorin e6 functionalized silk fibroin nanoparticles for targeted drug delivery and photodynamic therapy

Publication date: April 2018
Source:Biomaterials, Volume 161
Author(s): Baiping Mao, Caixia Liu, Wenwen Zheng, Xiaoheng Li, Renshan Ge, Haifa Shen, Xiaoling Guo, Qingquan Lian, Xian Shen, Chao Li
Regenerated silk fibroin (SF) is a natural biomacromolecule with excellent biocompatible and biodegradable properties. In this study, cyclic pentapeptide cRGDfk and Chlorin e6 (Ce6) were conjugated to SF polypeptides, and genipin was used to prepare 5-fluorouracil (5-FU) doped SF-based nanoparticles (NPs). The photodynamic therapy (PDT) potential and active targeting properties were systematically investigated in αvβ3 integrin receptor over-expressed MGC-803 cells in vitro. The results revealed that treatment with the multifunctional SF-based NPs and PDT, high level of reactive oxygen species (ROS) and cell death can be induced in MGC-803 cells. Combine with PDT, the in vivo antitumor effect of the SF-based NPs was evaluated in gastric cancer xenograft mice model. The results demonstrated that the SF-based NPs had ideal active tumor targeting property and the tumor burden can be reduced noticeably. Furthermore, the organs of mice in SF NPs treatment groups did not show obvious toxicity, demonstrating good biocompatibility and security profiles of SF NPs in vivo. Overall, our results suggest that the SF-based NPs are promising drug delivery carriers, together with PDT, the multimodality therapy could be potential regimen in future clinical cancer treatment.

Graphical abstract

http://ift.tt/2stqMZb

Highly stable molybdenum dioxide nanoparticles with strong plasmon resonance are promising in photothermal cancer therapy

Publication date: May 2018
Source:Biomaterials, Volume 163
Author(s): Wei Liu, Xinshi Li, Wentao Li, Qiqi Zhang, Hua Bai, Junfang Li, Guangcheng Xi
Photothermal therapy (PTT) is one of promising cancer therapy with high efficiency and minimal invasiveness. Exploiting of perfect PTT agent is vital to improve the therapy. In this study, a new type of bow tie-like molybdenum dioxide (MoO2) nanoparticles was successfully synthesized. These nanobow-ties had strong localized surface plasmon resonance (SPR) effect from visible to near infrared regions, and exhibited ultrahigh chemical stability. They could not only withstand high temperature heating without oxidation, but also resist the corrosion of strong acid and alkali. Meanwhile, the MoO2 nanoparticles were highly stable in protein-containing biological medium, though they partly degraded in PBS solution. Both in vivo and in vitro experiments indicated that they exhibited inappreciable toxicity. Under illumination of near infrared laser, they showed excellent PTT effect, as revealed by significant inhibition of cancer cell viability in vitro and efficient destruction in tumor tissue growth in vivo. These MoO2 nanoparticles possessed highly chemical stability and low toxicity with high PTT efficiency, thus promising them high potential as nanoagent in cancer treatment.

Graphical abstract

http://ift.tt/2o0mmEl

Photo-tearable tape close-wrapped upconversion nanocapsules for near-infrared modulated efficient siRNA delivery and therapy

Publication date: May 2018
Source:Biomaterials, Volume 163
Author(s): Yue Zhang, Kewei Ren, Xiaobo Zhang, Zhicong Chao, Yuqin Yang, Deju Ye, Zhihui Dai, Ying Liu, Huangxian Ju
RNA interference (RNAi) has become an appealing therapeutic approach for cancer and other diseases. One key challenge is the effective protection of these small fragile biomolecules against complicated physiological environments as well as efficient on-demand release. Here we design a photo-tearable polymer tape close-wrapped nanocapsule for efficient NIR modulated siRNA delivery. The photo-tearable nanocapsules comprise core-shell upconversion nanoparticles (UCNPs) coated with mesoporous silica layer for loading of photosensitizer hypocrellin A (HA) and small interfering RNA (siRNA) against polo-like kinase 1 (PLK1), and covalently bound thin membranes of polyethylene glycol (PEG) via a synthesized photocleavable linker (PhL). Upon irradiation at 980 nm, the UCNPs produce UV emissions to break PhL and tear out PEG membrane for siRNA release, and blue emissions to activate HA for generating reactive oxygen species (ROS). The close PEG membrane wrapping not only guarantees the efficient intracellular photocleavage, but also extends the circulation time and protects the loaded cargos from leakage and degradation. The ROS assists endosomal escape of the loaded cargos, therefore effectively improves the gene silencing efficiency and the suppressions of cell proliferation in vitro and tumor growth in vivo. The proposed photo-tearable tape-wrapped nanocapsules have promising potential application in precision medicine.

Graphical abstract

http://ift.tt/2BuPcV0

STINGel: Controlled release of a cyclic dinucleotide for enhanced cancer immunotherapy

Publication date: May 2018
Source:Biomaterials, Volume 163
Author(s): David G. Leach, Neeraja Dharmaraj, Stacey L. Piotrowski, Tania L. Lopez-Silva, Yu L. Lei, Andrew G. Sikora, Simon Young, Jeffrey D. Hartgerink
Recent advancements in the field of immunotherapy have yielded encouraging results for the treatment of advanced cancers. Cyclic dinucleotides (CDNs) are a powerful new class of immunotherapy drugs known as STING (Stimulator of Interferon Genes) agonists, currently in clinical trials. However, previous studies of CDNs in murine cancer models have required multiple injections, and improve survival only in relatively nonaggressive tumor models. Therefore, we sought to improve the efficacy of CDN immunotherapy by developing a novel biomaterial we call "STINGel." STINGel is an injectable peptide hydrogel that localizes and provides controlled release of CDN delivery, showing an 8-fold slower release rate compared to a standard collagen hydrogel. The carrier hydrogel is a positively charged, MultiDomain Peptide (MDP) which self-assembles to form a nanofibrous matrix and is easily delivered by syringe. The highly localized delivery of CDN from this nanostructured biomaterial affects the local histological response in a subcutaneous model, and dramatically improves overall survival in a challenging murine model of head and neck cancer compared to CDN alone or CDN delivered from a collagen hydrogel. This study demonstrates the feasibility of biomaterial-based immunotherapy platforms like STINGel as strategies for increasing the efficacy of CDN immunotherapies.

Graphical abstract

http://ift.tt/2o0y1TG

Time-responsive osteogenic niche of stem cells: A sequentially triggered, dual-peptide loaded, alginate hybrid system for promoting cell activity and osteo-differentiation

Publication date: May 2018
Source:Biomaterials, Volume 163
Author(s): Zuyuan Luo, Siqi Zhang, Jijia Pan, Rui Shi, Hao Liu, Yalin Lyu, Xiao Han, Yan Li, Yue Yang, Zhixiu Xu, Yi Sui, En Luo, Yuanyuan Zhang, Shicheng Wei
The efficacy of stem cell-based bone tissue engineering has been hampered by cell death and limited fate control. A smart cell culture system with the capability of sequentially delivering multiple factors in specific growth stages, like the mechanism of the natural extracellular matrix modulating tissue formation, is attractive for enhancing cell activity and controlling cell fate. Here, a bone forming peptide-1 (BFP-1)-laden mesoporous silica nanoparticles (pep@MSNs) incorporated adhesion peptide, containing the arginine-glycine-aspartic acid (RGD) domain, modified alginate hydrogel (RA) system (pep@MSNs-RA) was developed to promote the activity and stimulate osteo-differentiation of human mesenchymal stem cells (hMSCs) in sequence. The survivability and proliferation of hMSCs were enhanced in the adhesion peptide modified hydrogel. Next, BFP-1 released from pep@MSNs induced hMSCs osteo-differentiation after the proliferation stage. Moreover, BFP-1 near the cells was self-captured by the additional cell-peptide cross-linked networks formed by the ligands (RGD) binding to receptors on the cell surface, leading to long-term sustained osteo-stimulation of hMSCs. The results suggest that independent and sequential stimulation in proliferation and osteo-differentiation stages could synergistically enhance the survivability, expansion, and osteogenesis of hMSCs, as compared to stimulating alone or simultaneously. Overall, this study provided a new and valid strategy for stem cell expansion and osteo-differentiation in 2D or 3D culture systems, possessing potential applications in 3D bio-printing and tissue regeneration.

Graphical abstract

http://ift.tt/2BuYbp5

Liposomes of dimeric artesunate phospholipid: A combination of dimerization and self-assembly to combat malaria

Publication date: May 2018
Source:Biomaterials, Volume 163
Author(s): Muhammad Ismail, Longbing Ling, Yawei Du, Chen Yao, Xinsong Li
Artemisinin and its derivatives are highly effective drugs in the treatment of P. falciparum malaria. However, their clinical applications face challenges because of short half-life, poor bioavailability and growing drug resistance. In this article, novel dimeric artesunate phospholipid (Di-ART-GPC) based liposomes were developed by combination of dimerization and self-assembly to address these shortcomings. Firstly, Di-ART-GPC conjugate was synthesized by a facile esterification of artesunate (ART) and glycerophosphorylcholine (GPC) and confirmed by MS, ¹H NMR and ¹³C NMR. The conjugate was then assembled to form liposomes without excipient by thin film hydration method. The assembled Di-ART-GPC liposomes have typical multilamellar vesicle structure with bilayer morphology as determined by transmission electron microscopy (TEM) and cryogenic electron microscopy (cryo-EM). Moreover, the liposomes displayed an average hydrodynamic diameter of 190 nm and negative zeta potential at −20.35 mV as determined by Zetasizer. The loading capacity of ART was calculated approximately 77.6% by weight with this liposomal formulation after a simple calculation. In vitro drug release and degradation results showed that the Di-ART-GPC liposomes were stable in neutral physiological conditions but effectively degraded to release parent ART in simulated weakly acidic microenvironment. In vivo pharmacokinetics study revealed that Di-ART-GPC liposomes and conjugate have longer retention half-life in bloodstream. Importantly, Di-ART-GPC liposomes (IC50 0.39 nM) and the conjugate (IC50 1.90 nM) demonstrated excellent in vitro antiplasmodial activities without causing hemolysis of erythrocytes, which were superior to free ART (IC50 5.17 nM) and conventional ART-loaded liposomes (IC50 3.13 nM). Furthermore, the assembled liposomes resulted in enhanced parasites killing in P. berghei-infected mice in vivo with delayed recrudescence and improved survivability, compared to free ART administration. Based on these encouraging results, Di-ART-GPC liposomal formulation could be a replacement to parent ART in clinical malarial therapy after thorough investigation.



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Editorial Board

Publication date: April 2018
Source:Biomaterials, Volume 161





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Study of lipid metabolism by estimating the fat fraction in different breast tissues and in various breast tumor sub-types by in vivo 1H MR spectroscopy

Publication date: Available online 14 February 2018
Source:Magnetic Resonance Imaging
Author(s): Khushbu Agarwal, Uma Sharma, Sandeep Mathur, Vurthaluru Seenu, Rajinder Parshad, Naranamangalam R. Jagannathan
PurposeTo evaluate the utility of fat fraction (FF) for the differentiation of different breast tissues and in various breast tumor subtypes using in vivo proton (¹H) magnetic resonance spectroscopy (MRS).Methods¹H MRS was performed on 68 malignant, 35 benign, and 30 healthy volunteers at 1.5 T. Malignant breast tissues of patients were characterized into different subtypes based on the differences in the expression of hormone receptors and the FF was calculated. Further, the sensitivity and specificity of FF to differentiate malignant from benign and from normal breast tissues of healthy volunteers was determined using receiver operator curve (ROC) analysis.ResultsA significantly lower FF of malignant (median 0.12; range 0.01–0.70) compared to benign lesions (median 0.28; range 0.02–0.71) and normal breast tissue of healthy volunteers (median 0.39; range 0.06–0.76) was observed. No significant difference in FF was seen between benign lesions and normal breast tissues of healthy volunteers. Sensitivity and specificity of 75% and 68.6%, respectively was obtained to differentiate malignant from benign lesions. For the differentiation of malignant from healthy breast tissues, 76% sensitivity and 74.5% specificity was achieved. Higher FF was seen in patients with ER−/PR− status as compared to ER+/PR+ patients. Similarly, FF of HER2neu+ tumors were significantly higher than in HER2neu− breast tumors.ConclusionThe results showed the potential of in vivo ¹H MRS in providing insight into the changes in the fat content of different types of breast tissues and in various breast tumor subtypes.



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Editorial Board

Publication date: 15 February 2018
Source:Journal of Neuroscience Methods, Volume 296





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