Nanotechnology in food packaging materials: role and application of nanoparticles.

Global concerns about food security, driven by rising demand, have prompted the exploration of nanotechnology as a solution to enhance food supply. This shift comes in response to the limitations of conventional technologies in meeting the ever-increasing demand for food products. Consequently, nanoparticles play a crucial role in enhancing food production, preservation, and extending shelf life by imparting exceptional properties to materials. Nanoparticles and nanostructures with attributes like expansive surface area and antimicrobial efficacy, are versatile in both traditional packaging and integration into biopolymer matrices. These distinctive qualities contribute to their extensive use in various food sector applications. Hence, this review explores the physicochemical properties, functions, and biological aspects of nanoparticles in the context of food packaging. Furthermore, the synergistic effect of nanoparticles with different biopolymers, alongside its different potential applications such as food shelf-life extenders, antimicrobial agents and as nanomaterials for developing smart packaging systems were summarily explored. While the ongoing exploration of this research area is evident, our review highlights the substantial potential of nanomaterials to emerge as a viable choice for food packaging if the challenges regarding toxicity are carefully and effectively modulated.

Synthesis of silver-palladium Janus nanoparticles using co-sputtering of independent sources: experimental and theorical study.

Janus-type nanoparticles are important because of their ability to combine distinct properties and functionalities in a single particle, making them extremely versatile and valuable in various scientific, technological, and industrial applications. In this work, bimetallic silver-palladium Janus nanoparticles were obtained for the first time using the inert gas condensation technique. In order to achieve this, an original synthesis equipment built by Mantis Ltd. was modified by the inclusion of an additional magnetron in a second chamber, which allowed us to use two monometallic targets to sputter the two metals independently. With this arrangement, we could find appropriate settings at room temperature to promote the synthesis of bimetallic Janus nanoparticles. The structural properties of the resulting nanoparticles were investigated by transmission electron microscopy (TEM), and the chemical composition was analyzed by TEM energy dispersive spectroscopy (TEM-EDS), which, together with structural analysis, confirmed the presence of Janus-type nanostructures. Results of molecular dynamics and TEM simulations show that the differences between the crystalline structures of the Pd and Ag regions observed in the TEM micrographs can be explained by small mismatches in the orientations of the two regions of the particle. A density functional theory structural aims to understand the atomic arrangement at the interface of the Janus particle.

Physico-Chemical Properties of CdTe/Glutathione Quantum Dots Obtained by Microwave Irradiation for Use in Monoclonal Antibody and Biomarker Testing.

In this report, we present the results on the physicochemical characterization of cadmium telluride quantum dots (QDs) stabilized with glutathione and prepared by optimizing the synthesis conditions. An excellent control of emissions and the composition of the nanocrystal surface for its potential application in monoclonal antibody and biomarker testing was achieved. Two samples (QDYellow, QDOrange, corresponding to their emission colors) were analyzed by dynamic light scattering (DLS), and their hydrodynamic sizes were 6.7 nm and 19.4 nm, respectively. Optical characterization by UV-vis absorbance spectroscopy showed excitonic peaks at 517 nm and 554 nm. Photoluminescence spectroscopy indicated that the samples have a maximum intensity emission at 570 and 606 nm, respectively, within the visible range from yellow to orange. Infrared spectroscopy showed vibrational modes corresponding to the functional groups OH-C-H, C-N, C=C, C-O, C-OH, and COOH, which allows for the formation of functionalized QDs for the manufacture of biomarkers. In addition, the hydrodynamic radius, zeta potential, and approximate molecular weight were determined by dynamic light scattering (DLS), electrophoretic light scattering (ELS), and static light scattering (SLS) techniques. Size dispersion and the structure of nanoparticles was obtained by Transmission Electron Microscopy (TEM) and by X-ray diffraction. In the same way, we calculated the concentration of Cd2+ ions expressed in mg/L by using the Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-OES). In addition to the characterization of the nanoparticles, the labeling of murine myeloid cells was carried out with both samples of quantum dots, where it was demonstrated that quantum dots can diffuse into these cells and connect mostly with the cell nucleus.

One-Pot Synthesis of CdTe/ZnS Quantum Dots and their Physico-Chemical Characterization.

A known property of quantum dots (QDs) is their characteristic luminescence, which would make it possible to detect different types of cancers after being functionalized with some type of biological molecule. For this reason, in the present investigation a methodological analysis of the physicochemical characteristics of the CdTe/ZnS core/shell QDs was carried out, using techniques such as Optical Absorbance Spectroscopy (UV-Vis), Molecular Fluorescence, Fourier Transform Infrared Spectroscopy (FT-IR), Dynamic Light Scattering (DLS), X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Zeta Potential that allowed to verify the photoluminescent effectiveness of these semiconductor nanocrystals as an alternative to conventional techniques currently used for the detection of specific cancers smaller than 1 cm. The study consisted of theoretically determining the bandgap energy, the size of the nanocrystals and the molar absorptivity from the wavelength value for the maximum intensity of the excitonic peak. It was also possible to verify the maximum intensity for each sample and thus evaluate its photoluminescent response, as well as it was possible to determine the charge distribution, the hydrodynamic size and the surface composition of each quantum dot. The results obtained correspond to what has been reported in the literature, which makes them good candidates for the detection of cancer in precancerous stages.

Hybrid Materials Based on Nanoparticles Functionalized with Alkylsilanes Covalently Anchored to Epoxy Matrices.

In this work, the surface modification of zinc oxide nanoparticles (ZnO-NPs) with 3-glycidyloxy-propyl-trimethoxysilane (GPTMS) was investigated. The ZnO-NPs were synthesized using the physical method of continuous arc discharge in controlled atmosphere (DARC-AC). The surface modification was carried out using a chemical method with constant agitation for 24 h at room temperature. This surface functionalization of zinc oxide nanoparticles (ZnO-NPs-GPTMS) was experimentally confirmed by infrared spectroscopy (FT-IR), TGA, and XRD, and its morphological characterization was performed with SEM. The increase in mechanical bending properties in the two final hybrid materials compared to the base polymers was verified. An average increase of 67% was achieved with a moderate decrease in ductility. In the case of compressive strength, they showed mixed results, maintaining the properties. With respect to thermal properties, it was observed that inorganic reinforcement conferred resistance to degradation on the base material, giving a greater resistance to high temperatures.

Mycobacteriophages to Treat Tuberculosis: Dream or Delusion?

Rates of antimicrobial resistance are increasing globally while the pipeline of new antibiotics is drying up, putting patients with disease caused by drug-resistant bacteria at increased risk of complications and death. The growing costs for diagnosis and management of drug resistance threaten tuberculosis control where the disease is endemic and resources limited. Bacteriophages are viruses that attack bacteria. Phage preparations served as anti-infective agents long before antibiotics were discovered. Though small in size, phages are the most abundant and diverse biological entity on earth. Phages have co-evolved with their hosts and possess all the tools needed to infect and kill bacteria, independent of drug resistance. Modern biotechnology has improved our understanding of the biology of phages and their possible uses. Phage preparations are available to treat meat, fruit, vegetables, and dairy products against parasites or to prevent contamination with human pathogens, such as Listeria monocytogenes, Escherichia coli, or Staphylococcus aureus. Such phage-treated products are considered fit for human consumption. A number of recent case reports describe in great detail the successful treatment of highly drug-resistant infections with individualized phage preparations. Formal clinical trials with standardized products are slowly emerging. With its highly conserved genome and relative paucity of natural phage defence mechanisms Mycobacterium tuberculosis appears to be a suitable target for phage treatment. A phage cocktail with diverse and strictly lytic phages that kill all lineages of M. tuberculosis, and can be propagated on Mycobacterium smegmatis, has been assembled and is available for the evaluation of optimal dosage and suitable routes of administration for tuberculosis in humans. Phage treatment can be expected to be safe and active on extracellular organisms, but phage penetration to intracellular and granulomatous environments as well as synergistic effects with antibiotics are important questions to address during further evaluation.

A Prospective Randomized Trial of Drug-Eluting Balloons Versus Everolimus-Eluting Stents in Patients With In-Stent Restenosis of Drug-Eluting Stents: The RIBS IV Randomized Clinical Trial.

BACKGROUND: Treatment of patients with drug-eluting stent (DES) in-stent restenosis (ISR) remains a major challenge. OBJECTIVES: This study evaluated the comparative efficacy of drug-eluting balloons (DEB) and everolimus-eluting stents (EES) in patients presenting with DES-ISR. METHODS: The study design of this multicenter randomized clinical trial assumed superiority of EES for the primary endpoint, in-segment minimal lumen diameter at the 6- to 9-month angiographic follow-up. RESULTS: A total of 309 patients with DES-ISR from 23 Spanish university hospitals were randomly allocated to DEB (n = 154) or EES (n = 155). At late angiography (median 247 days; 90% of eligible patients), patients in the EES arm had a significantly larger minimal lumen diameter (2.03 ± 0.7 mm vs. 1.80 ± 0.6 mm; p < 0.01) (absolute mean difference: 0.23 mm; 95% CI: 0.07 to 0.38) [corrected], net lumen gain (1.28 ± 0.7 mm vs. 1.01 ± 0.7 mm; p < 0.01), and lower percent diameter stenosis (23 ± 22% vs. 30 ± 22%; p < 0.01) and binary restenosis rate (11% vs. 19%; p = 0.06), compared with patients in the DEB arm. Consistent results were observed in the in-lesion analysis. At the 1-year clinical follow-up (100% of patients), the main clinical outcome measure (composite of cardiac death, myocardial infarction, and target vessel revascularization) was significantly reduced in the EES arm (10% vs. 18%; p = 0.04; hazard ratio: 0.58; 95% CI: 0.35 to 0.98), mainly driven by a lower need for target vessel revascularization (8% vs. 16%; p = 0.035). CONCLUSIONS: In patients with DES-ISR, EES provided superior long-term clinical and angiographic results compared with DEB. (Restenosis Intra-Stent of Drug-Eluting Stents: Drug-Eluting Balloon vs Everolimus-Eluting Stent [RIBS IV]; NCT01239940).

Quality and high yield synthesis of Ag nanowires by microwave-assisted hydrothermal method.

Silver nanowires (Ag-NWs) were obtained using microwave-assisted hydrothermal method (MAH). The main advantage of the method is its high NWs production which is greater than 90%. It is also easy, fast, and highly reproducible process. One of the drawbacks presented so far in the synthesis of nanostructures by polyol path is the high temperature used in the process, which is superior than the boiling point of solvent (ethylene glycol), and also its excessive reaction time. Here, Ag-NWs with diameters of 70 to 110 nm were synthesized in 5 min in large quantities. Results showed that dimensions and shape of nanowires were very susceptible to changes with reaction parameters. The reactor power and reactor fill capacity were important for the synthesis. It was found that the reaction time needs to be decreased because of the NWs which start to deform and break up due to significant increase in the pressure's system. Energy-dispersive X-ray spectroscopy and electron diffraction analysis (SAED) did not show corresponding phases of AgO. Some aspects about synthesis parameters which are related to the percent yield and size of nanowires are also discussed.

Optical and structural characterization of oleic acid-stabilized CdTe nanocrystals for solution thin film processing.

This work presents results of the optical and structural characterization of oleic acid-stabilized cadmium telluride nanocrystals (CdTe-NC) synthesized by an organometallic route. After being cleaned, the CdTe-NC were dispersed in toluene to obtain an ink-like dispersion, which was drop-cast on glass substrate to deposit a thin film. The CdTe-NC colloidal dispersion as well as the CdTe drop-cast thin films were characterized with regard to the optical and structural properties. TEM analysis indicates that the CdTe-NC have a nearly spherical shape (3.5 nm as mean size). Electron diffraction and XRD diffraction analyses indicated the bulk-CdTe face-centered cubic structure for CdTe-NC. An additional diffraction line corresponding to the octahedral Cd3P2 was also detected as a secondary phase, which probably originates by reacting free cadmium ions with trioctylphosphine (the tellurium reducing agent). The Raman spectrum exhibits two broad bands centered at 141.6 and 162.3 cm(-1), which could be associated to the TO and LO modes of cubic CdTe nanocrystals, respectively. Additional peaks located in the 222 to 324 cm(-1) range, agree fairly well with the wavenumbers reported for TO modes of octahedral Cd3P2.

Titanium-nitride-oxIde-coated stents multicenter registry in diaBEtic patienTs: the TIBET registry.

We sought to explore the immediate clinical and angiographic results of the Titan(®) stent implantation in diabetic patients, as well as the major adverse cardiac events (MACE) at 6-month follow-up. We enrolled 156 consecutive diabetic patients admitted to undergo percutaneous intervention for at least one significant (50%) coronary lesion. All lesions were treated with the Titan(®) stent implantation according to the contemporary interventional techniques. Patients were prospectively followed-up for at least 6 months. The primary endpoint was MACE at 6-month follow-up [cardiac death, myocardial infarction (MI), or target lesion revascularization (TLR)]. Secondary endpoints included angiographic and clinical procedural success, in-hospital MACE, TLR at 6-month follow-up, and stent thrombosis. The mean age was 66.7 ± 9.6 years, (68.4% males). A total of 197 Titan(®) stents were implanted in 163 lesions. Direct stenting was performed in 45.2% of the cases. The mean stent diameter was 3.1 ± 0.61 mm, and the mean length was 18.0 ± 8.9 mm. Average stent deployment pressure was 13.9 ± 4.2 bars. Angiographic procedural success was achieved in 154 (98.7%) cases, and clinical procedural success was achieved in 153 (98.1%) cases. One patient developed in-hospital non-Q-wave MI following the procedure. Clinical follow-up was completed in 155 (99.4%) patients. Three patients (1.9%) died of a cardiac or unknown cause, and two (1.3%) developed MI. TLR was performed in 11 patients (7.1%). Cumulative MACE at 6-month follow-up occurred in 16 (10.3%) patients. No patient suffered stent thrombosis. Titan(®) stent implantation in diabetic patients achieves an excellent immediate clinical and angiographic outcome, with a low incidence of MACE at mid-term follow-up.

Growth of vertically aligned ZnO nanorods using textured ZnO films.

A hydrothermal method to grow vertical-aligned ZnO nanorod arrays on ZnO films obtained by atomic layer deposition (ALD) is presented. The growth of ZnO nanorods is studied as function of the crystallographic orientation of the ZnO films deposited on silicon (100) substrates. Different thicknesses of ZnO films around 40 to 180 nm were obtained and characterized before carrying out the growth process by hydrothermal methods. A textured ZnO layer with preferential direction in the normal c-axes is formed on substrates by the decomposition of diethylzinc to provide nucleation sites for vertical nanorod growth. Crystallographic orientation of the ZnO nanorods and ZnO-ALD films was determined by X-ray diffraction analysis. Composition, morphologies, length, size, and diameter of the nanorods were studied using a scanning electron microscope and energy dispersed x-ray spectroscopy analyses. In this work, it is demonstrated that crystallinity of the ZnO-ALD films plays an important role in the vertical-aligned ZnO nanorod growth. The nanorod arrays synthesized in solution had a diameter, length, density, and orientation desirable for a potential application as photosensitive materials in the manufacture of semiconductor-polymer solar cells. PACS: 61.46.Hk, Nanocrystals; 61.46.Km, Structure of nanowires and nanorods; 81.07.Gf, Nanowires; 81.15.Gh, Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.).

Clinical safety and efficacy of a novel thin-strut cobalt-chromium coronary stent system: results of the real world Coroflex Blue Registry.

OBJECTIVES: The aim of this registry was to evaluate the clinical efficacy and safety of the Coroflex Blue cobalt-chromium stent in real-world practice. BACKGROUND: The development of cobalt-chromium bare-metal stents (BMS) with thinner struts has lead to better deliverability and lower target-lesion revascularization rates compared with stainless steel BMS. METHODS: The Coroflex Blue Registry was an international, prospective, multicenter registry enrolling patients with symptomatic ischemic heart disease attributable to single de novo or restenotic nonstented lesions of a single vessel amenable for percutaneous stenting. The primary end point was clinically driven target-lesion revascularisation (TLR) 6 months after enrolment, secondary endpoints were technical/procedural success, in-hospital outcome, definite stent thrombosis and major adverse cardiac events (death, myocardial infarction, or TLR) after 6 months. RESULTS: The registry included 2,315 patients (mean age 64.3 +/- 11.1 years, 19.8% diabetes, 37.3% acute myocardial infarction). Although a complex lesion cohort with 60.3% Typ B(2)/C-lesions, the technical success rate was 99.1% and the procedural success rate 98.5%. The incidence of TLR after 6 months was 5.5% and the cumulative 6-month acute/subacute stent thrombosis rate was 1.6%. After 6 months cumulative event-free survival was 90.8% in all patients and 87% in patients with acute PCI for acute myocardial infarction. CONCLUSIONS: This registry demonstrates the safety and efficacy of the Coroflex Blue cobalt-chromium stent platform in real-world practice. In the era of drug-eluting stents (DES), these results raise the serious question if the use of DES for primary prevention of restenosis and TLR is really justified.

Cardiac rupture and tamponade during ventriculography.

Left ventricular free wall rupture after a myocardial infarction is a complication which is unusually seen during ventriculography. We present the case of a patient who developed a cardiac rupture and tamponade captured on ventriculography.

Late gadolinium-enhanced cardiovascular magnetic resonance identifies patients with standardized definition of ischemic cardiomyopathy: a single centre experience.

BACKGROUND: Definition of ischemic cardiomyopathy (IC) is not always obvious, which is why new criteria based on prognosis and the extent of the coronary artery disease (CAD) have been proposed. In the present study, we assess the capability of late gadolinium-enhanced cardiovascular magnetic resonance (CMR) for predicting IC as determined by standardized criteria previously reported. METHODS AND RESULTS: 123 patients with heart failure (HF) and left ventricular (LV) systolic dysfunction, underwent both late gadolinium-enhanced CMR and coronary angiography 37/123 (30%) of patients were assigned to the IC group and 86/123 (70%) to the non-IC group. Subendocardial late gadolinium enhancement (LGE) was found in 35/37 (94%) of patients in the IC group, whereas only 12/86 (14%) had this distribution in the non-IC group (p<0.001). There was a significant positive correlation between the extent of subendocardial LGE and that of the CAD as determined by the CAD Prognostic Index (r=0.78, p<0.01), the number of coronary stenoses > or = 50% (r=0.76, p<0.01) and the number of coronary stenoses of any percentage (r=0.70, p<0.01). CONCLUSION: In patients with HF and LV systolic dysfunction presence of subendocardial LGE makes an excellent indicator of underlying significant CAD, and the extent of the LGE correlates with the severity of the disease. It is therefore appealing as a method for diagnosing IC.

Right-to-left interatrial shunt despite normal pulmonary artery pressure. Anatomical implications.

Platypnea-orthodeoxia is a rare syndrome characterized by dyspnea induced by the upright position and relieved by supine position and an arterial deoxygenation increased by the upright position which improves during recumbency. In many cases, this syndrome has been associated with patent foramen ovale and right-to-left shunt. Several anatomical factors that can alter the atrial anatomy and facilitate shunting through an interatrial communication have been related with this syndrome. We present a case in which an enlarged aortic root was the main anatomical factor that contributed to transient right-to-left shunting induced by postural changes.

Therapeutic implications of in-stent restenosis located at the stent edge. Insights from the restenosis intra-stent balloon angioplasty versus elective stenting (RIBS) randomized trial.

AIMS: In patients with in-stent restenosis (ISR) several anatomic subgroups have been identified. ISR affecting the stent edge (EDG) is a poorly characterised subgroup with undefined therapeutic implications. We sought to determine the implications of ISR affecting the stent EDG. METHODS AND RESULTS: 450 patients included in the "Restenosis Intra-stent: Balloon angioplasty vs elective Stenting" (RIBS) randomized study, were analysed. EDG ISR was predefined in the protocol and the pattern of ISR analysed in a centralized core-lab. Fifty-two patients (12%) had EDG ISR (29 stent group, 23 balloon arm). Patients with EDG ISR had less severe [minimal lumen diameter (MLD) (0.78+/-0.3 vs 0.66+/-0.3 mm, p=0.05)] and shorter lesions (lesion length 10.2+/-6 vs 13.2+/-7 mm, p=0.003). Patients with EDG ISR more frequently required crossover (12% vs 3%, p=0.006) but eventually the immediate angiographic result and the long-term clinical and angiographic outcome was similar to that found in patients without EDG ISR. Patients with EDG ISR treated in the balloon and stent arms had similar baseline characteristics. However, after intervention, the immediate angiographic result was better in the stent arm (MLD 2.79+/-0.4 vs 2.35+/-0.3 mm, p=0.001). This difference persisted at late follow-up: MLD (1.93+/-0.7 vs 1.39+/-0.7 mm, p=0.01), recurrent restenosis (20% vs 50%, p=0.03). In addition, the 1-year event-free survival was significantly better (83% vs 52%, log rank p=0.01; Cox HR 0.28, 95%CI 0.09-0.79) in the stent arm. Moreover, stent implantation was an independent predictor of freedom from target vessel revascularization (HR 0.15, 95%CI 0.03-0.67, p=0.003). CONCLUSIONS: EDG ISR constitutes a specific subgroup with relevant therapeutic implications. In patients with EDG ISR, repeat stent implantation provides better clinical and angiographic outcome than conventional balloon angioplasty.

Role of Fas-mediated apoptosis and follicle-stimulating hormone on the developmental capacity of bovine cumulus oocyte complexes in vitro.

Follicular atresia is believed to be largely regulated by apoptosis. To further understand how apoptosis can affect cumulus cells and oocytes we have evaluated the incidence and regulation of apoptosis affecting bovine cumulus oocyte complexes in vitro. Expression of components of the Fas signaling pathway was studied in both oocytes and cumulus cells by polymerase chain reaction after reverse transcription, immunoblotting, and indirect immunofluorescence. Furthermore, the Fas signaling pathway was activated in cumulus oocyte complexes with an agonistic anti-Fas antibody during in vitro maturation in the presence or absence of FSH. Viability and incidence of apoptosis in cumulus cells were evaluated by assessing membrane integrity and nuclear morphology. Oocyte nuclear maturation was also analyzed, as well as cleavage rates, blastocyst formation rates, and blastocyst quality, following in vitro fertilization. Fas mRNA and protein were expressed both in oocytes and cumulus cells. FasL protein was found in cumulus cells but could not be detected in oocytes, despite its mRNA expression. Both activation of the Fas pathway and presence of FSH during in vitro maturation increased the incidence of apoptosis in cumulus cells, affecting predominantly the middle and peripheral regions of the cumulus. The observed increase, however, had no effect on the developmental competence of the oocytes.