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1.
Int J Biol Macromol ; 270(Pt 1): 132346, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38750859

ABSTRACT

The impact of dual sequential modifications using radio-frequency (RF) plasma and electron beam irradiation (EBI) on starch properties was investigated and compared with single treatments within an irradiation dose range of 5-20 kGy. Regardless of sequence, dual treatments synergistically affected starch properties, increasing acidity, solubility, and paste clarity, while decreasing rheological features with increasing irradiation dose. The molecular weight distribution was also synergistically influenced. Amylopectin distribution broadened particularly below 10 kGy. Amylose narrowed its distribution across all irradiation doses. This was due to dominating EBI-induced degradation and molecular rearrangements from RF plasma. With the highest average radiation-chemical yield (G) and degradation rate constant (k) of (2.12 ± 0.14) × 10-6 mol·J-1 and (3.43 ± 0.23) × 10-4 kGy-1, respectively, upon RF plasma pre-treatment, amylose underwent random chain scission. In comparison to single treatments, dual modification caused minor alterations in spectral characteristics and crystal short-range order structure, along with increased granule aggregation and surface irregularities. The synergistic effect was dose-dependent, significant up to 10 kGy, irrespective of treatment sequence. The highest synergistic ratio was observed when RF plasma preceded irradiation, demonstrating the superior efficiency of plasma pre-treatment in combination with EBI. This synergy has the potential to lower costs and extend starch's technological uses by enhancing radiation sensitivity and reducing the irradiation dose.


Subject(s)
Electrons , Molecular Weight , Plasma Gases , Starch , Starch/chemistry , Plasma Gases/pharmacology , Plasma Gases/chemistry , Solubility , Amylose/chemistry , Amylopectin/chemistry , Rheology
2.
Chirurgia (Bucur) ; 119(1): 65-75, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38465717

ABSTRACT

AIM: The aim of the present study is to assess some characteristics of blunt hepatic and splenic injuries in children, the non-operative management (NOM) procedures and efficiency, over a 5-year period in a tertiary hospital for children. Materials and Methods: We conducted a retrospective study on 32 patients with blunt liver and/or spleen injuries. Age, gender, mechanism of injury, hemoglobin and hematocrit levels, lenght of stay and bedrest, imaging diagnosis, hemostatics and transfusions, treatment, and discharge status were evaluated. Results: 58% of patients were males. Mean age was 10.7 years. The main mechanism of injury was motor vehicle accident. Ultrasound (US) and Computed Tomography (CT) found 56.2% patients with spleen injury and 43.8% with liver injuries. On US the most frequent injuries were lacerations, and on CT were splenic-grade III and hepatic-grade II. 84.4% of patients were hospitalized in Intensive Care Unit and 15.6% in the surgical unit. The mean hemoglobin and hematocrit were 10.91g/l and 33%, respectively.The treatment was non-operative for 84.4%, and operative for 15.6%. When discharged, 56.2% of patients were cured and 43.8% were improved. CONCLUSION: With a performing multidisciplinary team of surgeons, intensive care therapists and radiologists, NOM in pediatric patients with blunt liver and spleen injuries is safe and effective, may be conducted depending on the hemodynamic stability rather than the lesions' extension, and reduces the ICU lenght of stay, as well as the need for hemostatics and transfusion.


Subject(s)
Hemostatics , Wounds, Nonpenetrating , Male , Humans , Child , Female , Spleen/diagnostic imaging , Retrospective Studies , Treatment Outcome , Wounds, Nonpenetrating/diagnostic imaging , Wounds, Nonpenetrating/therapy , Liver/diagnostic imaging , Hemoglobins , Injury Severity Score
3.
J Funct Biomater ; 14(9)2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37754868

ABSTRACT

Herein, three different recipes of multi-component hydrogels were synthesized by e-beam irradiation. These hydrogels were obtained from aqueous polymer mixtures in which different proportions of bovine collagen gel, sodium carboxymethylcellulose (CMC), poly(vinylpyrrolidone), chitosan, and poly(ethylene oxide) were used. The cross-linking reaction was carried out exclusively by e-beam cross-linking at 25 kGy, a dose of irradiation sufficient both to complete the cross-linking reaction and effective for hydrogel sterilization. The hydrogels developed in this study were tested in terms of physical and chemical stability, mechanical, structural, morphological, and biological properties. They are transparent, maintain their structure, are non-adhesive when handling, and most importantly, especially from the application point of view, have an elastic structure. Likewise, these hydrogels possessed different swelling degrees and expressed rheological behavior characteristic of soft solids with permanent macromolecular network. Morphologically, collagen- and CMC based-hydrogels showed porous structures with homogeneously distributed pores assuring a good loading capacity with drugs. These hydrogels were investigated by indirect and direct contact studies with Vero cell line (CCL-81™, ATCC), demonstrating that they are well tolerated by normal cells and, therefore, showed promising potential for further use in the development of drug delivery systems based on hydrogels.

4.
Materials (Basel) ; 16(13)2023 Jun 23.
Article in English | MEDLINE | ID: mdl-37444866

ABSTRACT

In the present paper, hydrogels based on acrylic acid (20%), sodium alginate (0.5%) and poly(ethylene oxide) (0.1%) were obtained by electron beam irradiation at room temperature with doses between 5 and 20 kGy, using potassium persulfate in concentrations up to 0.3% as a reaction initiator. The influence of initiator concentration and irradiation dose on hydrogel network parameters, swelling and deswelling behavior, gelation and degradation points, structure and morphology were investigated. Cross-link density increased with the irradiation dose and initiator addition, except at 20 kGy. The gel fraction was over 87.0% in all cases. Swelling experiments in distilled water showed swelling degrees of 40,000% at an irradiation dose of 5 kGy when a concentration of 0.1% initiator was added. A relationship between the swelling degree and irradiation dose, cross-linking degree (that increases from 0.044 × 102 to 0.995 × 102 mol/cm3) and mesh size (that decreases from about 220 nm to 26 nm) was observed. The addition of only 0.1% of PP led to the obtaining of hydrogels with a swelling degree of 42,954% (about 430 g/g) at an irradiation dose of 5 kGy and of 7206% (about 62 g/g) at 20 kGy, which are higher percentages than those obtained in the same irradiation conditions but without PP.

5.
Nanomaterials (Basel) ; 13(6)2023 Mar 11.
Article in English | MEDLINE | ID: mdl-36985906

ABSTRACT

In fusion reactors, such as ITER or DEMO, the plasma used to generate nuclear reactions will reach temperatures that are an order of magnitude higher than in the Sun's core. Although the plasma is not supposed to be in contact with the reactor walls, a large amount of heat generated by electromagnetic radiation, electrons and ions being expelled from the plasma will reach the plasma-facing surface of the reactor. Especially for the divertor part, high heat fluxes of up to 20 MW/m2 are expected even in normal operating conditions. An improvement in the plasma-facing material (which is, in the case of ITER, pure Tungsten, W) is desired at least in terms of both a higher recrystallization temperature and a lower brittle-to-ductile transition temperature. In the present work, we discuss three microengineering routes based on inclusions of nanometric dispersions, which are proposed to improve the W properties, and present the microstructural and thermophysical properties of the resulting W-based composites with such dispersions. The materials' behavior after 6 MeV electron irradiation tests is also presented, and their further development is discussed.

6.
Polymers (Basel) ; 16(1)2023 Dec 21.
Article in English | MEDLINE | ID: mdl-38201697

ABSTRACT

High-quality convex colloidal photonic crystals can be grown on the tip of an optical fiber by self-assembly using the hanging drop method. They are convex-shaped, produce the diffraction of reflecting light with high efficiency (blazing colors), and have a high curvature. The convex colloidal crystals are easily detachable and, as free-standing objects, they are mechanically robust, allowing their manipulation and use as convex reflective diffraction devices in imaging spectrometers. Currently, the same characteristics are obtained by using gratings-based structures. The optical fiber/colloidal crystal interface is disordered; thus, no light diffraction can be registered. The ordering at this interface was highly increased by forming a polystyrene spacer on the optical fiber tip, which served as a self-assembly substrate for silica colloid, as a mechanical bond between the fiber and the crystal, and as a filler reservoir for an inverse-opal synthesis. The silica opal-like grown on the optical fiber tip can be transformed into a high-quality polystyrene (blazing colors) inverse-opal by using the polystyrene spacer as a filler. We found that the colloidal crystal axisymmetric self-assembles onto the optical fiber tip only if a maximum volume of the colloid drop is settled on a flat end of the polystyrene spacer.

7.
Beilstein J Nanotechnol ; 13: 1490-1504, 2022.
Article in English | MEDLINE | ID: mdl-36570613

ABSTRACT

This research work focuses on the fabrication and study of a series of nanocomposites consisting of two types of hydroxyapatite (HA), obtained by precipitate (HAP) and sol-gel (HAG) methods, and a boro-silico-phosphate bioglass. The microstructure and chemical, mechanical, and biological properties as functions of three factors, namely (i) the type of hydroxyapatite, (ii) glass content, and (iii) sintering temperature, were investigated. It was found that all of these factors affect the final composition and microstructure, especially, porosity, which shows significantly lower values for HAP-based composites than for HAG-based ones and higher values for higher glass content. This, in turn, has an impact on the microhardness, which exhibits a strong correlation with porosity, as well as on the mineralization capability and cell viability due to the different dissolution rate.

8.
Polymers (Basel) ; 14(11)2022 May 26.
Article in English | MEDLINE | ID: mdl-35683831

ABSTRACT

Silica and polystyrene spheres with a small size ratio (r = 0.005) form by sequential hanging drop self-assembly, a binary colloidal crystal through which calcination transforms in a silica-ordered concavity array. These arrays are capable of light Bragg diffraction and shape dependent optical phenomena, and they can be transformed into inverse-opal structures. Hierarchical 2D and 3D super-structures with ordered concavities as structural units were fabricated in this study.

9.
Ther Clin Risk Manag ; 18: 513-522, 2022.
Article in English | MEDLINE | ID: mdl-35516165

ABSTRACT

Paraovarian cysts (POCs) develop within the broad ligament of the uterus. POCs are considered to be giant when the threshold of 150 mm is exceeded. Clinical signs and symptoms occur as a consequence of the pressure effect on adjacent organs or due to complications. Abdominal ultrasonography, computed tomography or magnetic resonance imaging are useful imaging tools, but most often the exact origin of such voluminous cysts is revealed only by surgical exploration. The review aims to appraise and update the diagnostic, the histological aspects and the treatment of the giant POCs in rare cases. We carried out a systematic search in Medline-PubMed, Google Scholar and ResearchGate electronic databases. Twenty-seven papers fulfilling the selection criteria were included in the review. The data extracted included information about first author, year of publication, country, patient age, size and side of the POCs, symptoms, tumoral markers, imaging methods, preoperative diagnosis, surgical management and histopathological findings. Although not very numerous, all the studies highlighted the low incidence of giant POCs, the impossibility of establishing the origin of the cystic mass by clinical and imaging methods even with advanced technical tools and the low risk of torsion (11.1%). Despite the recognized benign nature of POCs, we found an unexpected high percent (25.9%) of borderline giant POCs. Surgical excision is the only treatment option. Ovarian-sparing surgery was performed in 85.1% of the cases, and minimally invasive techniques were applied in only 42.9% of the patients, which demonstrates the need of a high-level laparoscopic expertise. Knowledge of this pathology, its recognition as a possible etiology of an abdominopelvic cyst, and a higher awareness of the possibility of a borderline histology in giant POCs are required for the proper management of these particular cases.

10.
Int J Womens Health ; 14: 15-27, 2022.
Article in English | MEDLINE | ID: mdl-35046732

ABSTRACT

Undescended ovary (UO) is an uncommon congenital condition characterized by the presence of the adnexa above the common iliac vessels, with an estimated incidence of 0.3-2%. Because of its rarity, it is usually presented as a case report. A thorough knowledge of the ovarian embryological development is essential for the clinician, who must be warned about the possibility of associated Müllerian and renal malformations. There may be asymptomatic patients, incidentally diagnosed during infertility evaluation, but when symptoms occur, these are unspecific and most often this disorder is misdiagnosed, the accurate diagnosis being established intraoperatory. The malignant potential of an UO is accepted, although no such cases were reported. The role of the UO in infertility is still unclear, despite evidence of its normal function. Complications are linked to the ovary (cyst formation, cyst ruptures or tumors) or to the undescended fallopian tube (ectopic pregnancies). The management should be conservative, but there is no consensus about whether it is necessary to excise the ipsilateral undescended tube. We included a short case presentation of an UO cystadenoma misdiagnosed as a renal cyst, which depicts all diagnostic and management dilemmas and inspired us to write this review. The present literature review includes all the cases reported from the early 20th century to the present, with updated data about epidemiology, pathophysiology, clinical and imaging diagnosis, treatment options and prognosis of this rare condition. This paper aims to establish some directions in the diagnosis and management of similar patients and to remind us that, no matter how advanced the imaging investigation techniques might be, a correct preoperative diagnosis may often be missed.

11.
Polymers (Basel) ; 13(23)2021 Nov 24.
Article in English | MEDLINE | ID: mdl-34883585

ABSTRACT

A polyester fabric with rectangular openings was used as a sacrificial template for the guiding of a sub-micron sphere (polystyrene (PS) and silica) aqueous colloid self-assembly process during evaporation as a patterned colloidal crystal (PCC). This simple process is also a robust one, being less sensitive to external parameters (ambient pressure, temperature, humidity, vibrations). The most interesting feature of the concave-shape-pattern unit cell (350 µm × 400 µm × 3 µm) of this crystal is the presence of triangular prisms at its border, each prism having a one-dimensional sphere array at its top edge. The high-quality ordered single layer found inside of each unit cell presents the super-prism effect and left-handed behavior. Wider yet elongated deposits with ordered walls and disordered top surfaces were formed under the fabric knots. Rectangular patterning was obtained even for 20 µm PS spheres. Polyester fabrics with other opening geometries and sizes (~300-1000 µm) or with higher fiber elasticity also allowed the formation of similar PCCs, some having curved prismatic walls. A higher colloid concentration (10-20%) induces the formation of thicker walls with fiber-negative replica morphology. Additionally, thick-wall PCCs (~100 µm) with semi-cylindrical morphology were obtained using SiO2 sub-microspheres and a wavy fabric. The colloidal pattern was used as a lithographic mask for natural lithography and as a template for the synthesis of triangular-prism-shaped inverted opals.

12.
Molecules ; 26(20)2021 Oct 14.
Article in English | MEDLINE | ID: mdl-34684773

ABSTRACT

Mechanical activation and mechanochemical reactions are the subjects of mechanochemistry, a special branch of chemistry studied intensively since the 19th century. Herein, we comparably describe two synthesis methods used to obtain the following layered double hydroxide doped with cerium, Mg3Al0.75Ce0.25(OH)8(CO3)0.5·2H2O: the mechanochemical route and the co-precipitation method, respectively. The influence of the preparation method on the physico-chemical properties as determined by multiple techniques such as XRD, SEM, EDS, XPS, DRIFT, RAMAN, DR-UV-VIS, basicity, acidity, real/bulk densities, and BET measurements was also analyzed. The obtained samples, abbreviated HTCe-PP (prepared by co-precipitation) and HTCe-MC (prepared by mechanochemical method), and their corresponding mixed oxides, Ce-PP (resulting from HTCe-PP) and Ce-MC (resulting from HTCe-MC), were used as base catalysts in the self-condensation reaction of cyclohexanone and two Claisen-Schmidt condensations, which involve the reaction between an aromatic aldehyde and a ketone, at different molar ratios to synthesize compounds with significant biologic activity from the flavonoid family, namely chalcone (1,3-diphenyl-2-propen-1-one) and flavone (2-phenyl-4H-1benzoxiran-4-one). The mechanochemical route was shown to have indisputable advantages over the co-precipitation method for both the catalytic activity of the solids and the costs.

13.
Polymers (Basel) ; 13(12)2021 Jun 11.
Article in English | MEDLINE | ID: mdl-34208234

ABSTRACT

Polymeric composites based on natural rubber (NR) and plasticized starch (PS) obtained by peroxide cross-linking have been subjected to electron beam irradiation in order to investigate their degradation. The amount of PS ranged from 10 to 50 phr and the irradiation dose from 150 to 450 kGy. Irradiation was performed in atmospheric conditions using a linear electron accelerator of 5.5 MeV. Changes in chemical, physical, structural, and morphological properties of composites were correlated with variables, such as PS loading and irradiation dose. Thus, mechanical properties, gel fraction, cross-linking degree, water uptake, weight loss in toluene/water were compared with those obtained before irradiation. The changes in structure and morphology were studied by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. Both PS loading and irradiation dose were found to be responsible for the degradation installing. Moreover, it has been shown that at the dose of 450 kGy, chain scission is dominant over cross-linking.

14.
Medicina (Kaunas) ; 57(5)2021 May 13.
Article in English | MEDLINE | ID: mdl-34068430

ABSTRACT

Introduction: Meckel's diverticulum (MD), a remnant of the omphaloenteric duct, is among the most frequent intestinal malformations. Another embryonic vestige is the urachus, which obliterates, becoming the median umbilical ligament; the failure of this process can lead to a urachal cyst formation. We present a case of Meckel diverticulitis misdiagnosed as an infected urachal cyst. Presentation of case: A 16-year-old girl presented with hypogastric pain, fever and vomiting. She had undergone an appendectomy 6 years prior and no digestive malformation had been documented. In the last 2 years, she had 3 events of urinary tract infections with Escherichia coli, and anabdominal ultrasound discovered a 28/21 mm hypoechogenic preperitoneal round tumor, anterosuperior to the bladder. We established the diagnosis of an infected urachal cyst, confirmed later by magnetic resonance imaging. Intraoperative, we found MD with necrotic diverticulitis attached to the bladder dome. Discussions: Meckel's diverticulum and urachal cyst (UC) are embryonic remnants. Both conditions are usually asymptomatic, being incidentally discovered during imaging or surgery performed for other abdominal pathology. Imaging diagnosis is accurate for UC, but for MD they are low sensitivity and specificity. For UC treatment, there is a tendency to follow an algorithm related to age and symptoms, but there is no general consensus on whether to perform a routine resection of incidentally discovered MD. Conclusion: Preoperatory diagnosis of MD represents a challenge. We want to emphasize the necessity of a thorough inspection of the small bowel during all abdominal surgical interventions and MD surgical excision regardless of its macroscopic appearance. These two actions seem to be the best prophylaxis measures for MD complications and consequently to avoid emergency surgery, in which case more extensive surgical procedures on an unstable patient may be needed.


Subject(s)
Diverticulitis , Meckel Diverticulum , Urachal Cyst , Adolescent , Diagnostic Errors , Female , Humans , Meckel Diverticulum/diagnostic imaging , Meckel Diverticulum/surgery , Urachal Cyst/diagnostic imaging , Urachal Cyst/surgery
15.
Sensors (Basel) ; 20(15)2020 Aug 02.
Article in English | MEDLINE | ID: mdl-32748872

ABSTRACT

The present paper reviews, for the first time, to the best of our knowledge, the most recent advances in research concerning two popular devices used for foot motion analysis and health monitoring: smart socks and in-shoe systems. The first one is representative of textile-based systems, whereas the second one is one of the most used pressure sensitive insole (PSI) systems that is used as an alternative to smart socks. The proposed methods are reviewed for smart sock use in special medical applications, for gait and foot pressure analysis. The Pedar system is also shown, together with studies of validation and repeatability for Pedar and other in-shoe systems. Then, the applications of Pedar are presented, mainly in medicine and sports. Our purpose was to offer the researchers in this field a useful means to overview and select relevant information. Moreover, our review can be a starting point for new, relevant research towards improving the design and functionality of the systems, as well as extending the research towards other areas of applications using sensors in smart textiles and in-shoe systems.


Subject(s)
Shoes , Sports , Clothing , Foot , Gait , Textiles
16.
Beilstein J Nanotechnol ; 10: 9-21, 2019.
Article in English | MEDLINE | ID: mdl-30680275

ABSTRACT

Zn/F co-doped SnO2 nanoparticles with a mean diameter of less than 15 nm and a narrow size distribution were synthesized by a one-step laser pyrolysis technique using a reactive mixture containing tetramethyltin (SnMe4) and diethylzinc (ZnEt2) vapors, diluted Ar, O2 and SF6. Their structural, morphological, optical and electrical properties are reported in this work. The X-ray diffraction (XRD) analysis shows that the nanoparticles possess a tetragonal SnO2 crystalline structure. The main diffraction patterns of stannous fluoride (SnF2) were also identified and a reduction in intensity with increasing Zn percentage was evidenced. For the elemental composition estimation, energy dispersion X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) measurements were performed. In general, both analyses showed that the Zn percentage increases with increasing ZnEt2 flow, accompanied at the same time by a decrease in the amount of F in the nanopowders when the same SF6 flow was employed. The Raman spectra of the nanoparticles show the influence of both Zn and F content and crystallite size. The fluorine presence is due to the catalytic partial decomposition of the SF6 laser energy transfer agent. In direct correlation with the increase in the Zn doping level, the bandgap of co-doped nanoparticles shifts to lower energy (from 3.55 to 2.88 eV for the highest Zn dopant concentration).

17.
Talanta ; 154: 438-45, 2016 07 01.
Article in English | MEDLINE | ID: mdl-27154697

ABSTRACT

A Laccase-based biosensor for the determination of phenolic compounds was developed by using Matrix Assisted Pulsed Laser Evaporation as an innovative enzyme immobilization technique. and the deriving biosensor was characterized and applied for the first time. Laccase was immobilized onto different substrates including screen printed carbon electrodes and spectroscopic, morphologic and electrochemical characterizations were carried out. A linear range from 1 to 60µM was achieved working at 5.5pH and -0.2V detection potential vs Ag pseudoreference. The limits of detection and quantification were found to be 1 and 5µM, respectively. A good fabrication reproducibility, stability of response and selectivity toward interferents were also found The potential of the developed biosensor was tested in the determination of total polyphenol content in real matrices (tea infusion, ethanolic extract from Muscari comosum bulbs and aqueous solution of a food supplement from black radish root and artichoke leaves) and the results were compared with those obtained by using the Folin-Ciocalteu method.


Subject(s)
Biosensing Techniques , Electrodes , Enzymes, Immobilized , Laccase , Reproducibility of Results , Volatilization
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