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1.
Diseases ; 12(4)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38667536

RESUMO

Gastric cancer ranks as the fifth most common cancer, and the assessment of inflammatory biomarkers in these patients holds significant promise in predicting prognosis. Therefore, data from patients undergoing surgical intervention for gastric cancer over a 7-year period were analyzed. This study was retrospective and involved a preoperative investigation of six inflammatory parameters derived from complete blood counts. Statistical analysis revealed a significant increase in the leucocyte-to-monocyte ratio (LMR) (p = 0.048), along with a significant decrease in the number of lymphocytes and monocytes compared to patients with successful discharge. Taking into consideration patients undergoing emergency surgery, a significant increase in the LMR (p = 0.009), neutrophil-to-lymphocyte ratio (NLR) (p = 0.004), Aggregate Index of Systemic Inflammation (AISI) (p = 0.01), and Systemic Immune-Inflammation Index (SII) (p = 0.028) was observed. Regarding relapse, these patients exhibited significant increases in AISI (p = 0.032) and SII (p = 0.047). Inflammatory biomarkers represent a valuable tool in evaluating and predicting the prognosis of patients with gastric cancer.

2.
Microorganisms ; 12(3)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38543523

RESUMO

BACKGROUND: Venous leg ulcers (VLUs) are a common chronic wound condition susceptible to infection by various bacterial species. Understanding bacterial presence and antibiotic sensitivity is crucial for effective treatment. Methodsː Medical records of 60 patients diagnosed with the C6 chronic venous insufficiency stage were analyzed retrospectively. The patients were divided into an active recurrent VLU group (33 cases) and a first-onset active VLU group (27 cases). Bacterial identification, antibiotic sensitivity, and laboratory markers were assessed. Resultsː Pseudomonas aeruginosa was the most prevalent bacterial species in both the study (72.72%) and control (37.03%) groups, along with other common bacteria such as Proteus mirabilis, Enterococcus sp., Staphylococcus aureus, Acinetobacter baumannii, Klebsiella spp., and Escherichia coli. Furthermore, uncommon bacteria, including Providencia rettgeri, Group B Streptococcus, and Salmonella Paratyphi B, and a fungal infection with Candida albicans, were identified only in the study group, while Morganella morganii was found exclusively in the control group. Pseudomonas aeruginosa showed significant sensitivity to several antibiotics, particularly Amikacin and Meropenem. Nonspecific laboratory markers, such as CRP, fibrinogen, ESR, WBC, CK, neutrophils, and lymphocytes, revealed statistically significant differences between groups, indicating their potential as biomarkers for monitoring recurrent VLUs. Conclusionsː These results highlight the need for comprehensive diagnostic approaches to effectively manage VLU infections and improve patient outcomes. Further research is warranted to explore factors influencing the presence of uncommon bacteria and to develop targeted interventions for VLU management.

3.
Chirurgia (Bucur) ; 119(1): 56-64, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38465716

RESUMO

AIM: This study presents a comparative analysis of cryostripping to conventional saphenectomy. Materials and Methods: The study included 2191 patients admitted in the Phlebology Department, 1st Surgical Department, Emergency County Hospital Timisoara, between September 2013 and April 2023, between September 2013 and April 2023, who underwent saphenectomy by cryostripping (1327 patients) or conventionally (864 patients). We compared the duration and costs of the procedure, hospitalization period, post-operative results, method feasibility, as well as the technical advantages of cryostripping compared to conventional surgery. Results: A smaller proximal incision, compared to the classic operation, as well the fact that distal counter incision is not necessary, represents technical advantages of this procedure. Average duration of the intervention was 41 +- 12.8 minutes, consumables costs were about 52 +- 10 EUR/intervention, with an average hospitalization period was 1.05 +- 0.41 days. The post-operative results were favourable, early complications rate being reduced (ecchymoses Phi; 2 cm - 33.23%; hematoma - 2.11%; deep vein thrombosis - 0.15%; transient paresthesias 3.01%). Compared to classic saphenectomy, the costs of consumables/intervention are similar, intervention time, hospitalization period and complication rate being statistically significantly lower. An advantage of the method is the fact that the cryo-probes can be sterilized, being reusable; from the economic point of view, the technique perfectly fits in both public hospitals and private clinics. Conclusions: Cryostripping is a radical surgical procedure which bring a significant number of advantages compared to the classic saphenectomy, being an effective alternative in CVD treatment.


Assuntos
Veia Safena , Humanos , Resultado do Tratamento , Estudos Retrospectivos , Veia Safena/cirurgia
4.
Diseases ; 12(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38248366

RESUMO

This study hypothesized that botulinum toxin (Botox) therapy would sustainably reduce sweat production in axillary hyperhidrosis patients over one year and significantly improve various quality-of-life aspects, including psychological well-being, social interactions, and daily functioning. The objectives were to quantitatively measure changes in sweat production and qualitatively assess the evolving impact on patients' quality of life over one year. Conducted prospectively at the Pius Brinzeu Clinical Emergency Hospital in Timisoara, Romania, this study complied with ethical standards and included adults with primary axillary hyperhidrosis unresponsive to conventional treatments. Participants underwent Botox injections and were evaluated at baseline, six months, and one year, using the Hyperhidrosis Disease Severity Scale (HDSS), WHOQOL-BREF, and the Dermatology Life Quality Index (DLQI), among other tools. Involving 81 patients, the study showed significant improvements in sweat production and quality-of-life metrics. Sweat production decreased from 0.81 g to 0.23 g per 15 min over one year (p < 0.001). HDSS scores reduced from 3.4 to 1.5, indicating a decrease in symptom severity (p < 0.001). The DLQI total score, assessing life quality impact, notably dropped from 19.9 to 6.9 (p < 0.001). Quality-of-life domains also showed significant improvements, especially in the social (from 65.3 to 73.4, p < 0.001) and environmental aspects (from 68.0 to 72.1, p < 0.001). Higher HDSS and sweat production were significantly associated with a lower quality of life on the DLQI (B coefficients of -4.1 and -2.5, respectively). Botulinum toxin therapy proved effective in reducing sweat production and improving the quality of life in axillary hyperhidrosis patients over a one-year period. These improvements were statistically significant in both physical and psychosocial domains. The study highlights the potential long-term benefits of Botox therapy for hyperhidrosis.

5.
J Clin Med ; 13(2)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38256449

RESUMO

This longitudinal study aimed to assess the quality of life in patients with anal fissures treated with botulinum toxin (Botox) injections over a one-year period. The study hypothesized that Botox injections would significantly improve quality of life and that these improvements would be sustained over a year. Conducted as a cross-sectional study, it assessed adults diagnosed with chronic anal fissures unresponsive to conventional treatments. Participants received 25 U of Botox in two sessions and their quality of life was assessed using the WHOQOL-BREF, COPE-60, Hospital Anxiety and Depression Scale (HADS), and SF-36 surveys. Data were collected at baseline six months and one year post-treatment. The study involved 113 patients, with a mean age of 38.1 years. Significant improvements were observed in the WHOQOL-BREF scores across all domains from baseline to 12 months (physical domain: 49.4 ± 10.5 to 70.2 ± 10.6, p < 0.001; mental domain: 34.8 ± 11.2 to 61.9 ± 11.5, p < 0.001). SF-36 scores also showed significant enhancements in physical and mental health components (physical: 44.3 ± 7.5 to 56.9 ± 5.9, p < 0.001; mental: 41.1 ± 7.2 to 54.4 ± 6.3, p < 0.001). Additionally, significant improvements were noted in patient perception on quality of life from the perspective of various aspects including physical discomfort, pain management, and mood and emotional well-being. The study demonstrated that Botox injections significantly improved the quality of life in patients with chronic anal fissures, with sustained benefits observed over a year. These findings suggest Botox as an effective treatment modality for enhancing life quality in patients with this condition, highlighting the potential for broader applications in managing chronic anal fissures.

6.
Toxins (Basel) ; 16(1)2024 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276535

RESUMO

Facial hyperhidrosis is a debilitating condition that can severely impact the quality of life. This study aimed to assess the long-term utility of Botulinum toxin type A therapy (BTA) for facial hyperhidrosis and its impact on quality of life over a one-year period. Conducted at the Pius Brinzeu Clinical Emergency Hospital in Timisoara, Romania, this longitudinal observational study involved 77 adult patients with primary facial hyperhidrosis. Participants received two sessions of Botulinum toxin injections (50 U IncoBTX-A each) and were evaluated at baseline, 6 months, and 12 months using the Hyperhidrosis Disease Severity Scale (HDSS), WHOQOL-BREF, Dermatology Life Quality Index (DLQI), and a bespoke survey. The study demonstrated significant reductions in HDSS scores from 3.6 ± 0.5 to 1.2 ± 0.8 post-treatment, sustained at 1.3 ± 0.6 at 12 months (p-value < 0.001). DLQI scores markedly decreased from 24.8 ± 4.2 to 6.2 ± 2.1 post-treatment, stabilizing at 6.5 ± 2.5 at 12 months (p-value < 0.001). Sweat production significantly dropped from 0.75 g ± 0.15 to 0.18 g ± 0.07 per 15 min (p-value < 0.001). WHOQOL-BREF scores improved notably in the mental domain from 66.7 ± 6.1 to 70.8 ± 5.2 at 12 months (p-value < 0.001), with physical and social domains also showing significant improvements. Correlation analysis revealed strong negative correlations between DLQI total score and HDSS (rho = -0.72, p-value < 0.001) and sweat production (rho = -0.68, p-value < 0.001). Regression analysis indicated significant predictors for DLQI total score, including HDSS (B Coefficient = -3.8, p-value < 0.001) and sweat production (B Coefficient = -2.2, p-value < 0.001). BTA therapy significantly improved the quality of life in facial hyperhidrosis patients, with lasting effects on symptom severity, sweat production, and quality of life domains. The correlation and regression analyses further substantiated the treatment's impact on both physical and psychological aspects. These findings advocate Botulinum toxin as a viable long-term treatment for facial hyperhidrosis.


Assuntos
Toxinas Botulínicas Tipo A , Hiperidrose , Adulto , Humanos , Resultado do Tratamento , Qualidade de Vida , Hiperidrose/diagnóstico , Hiperidrose/tratamento farmacológico , Toxinas Botulínicas Tipo A/uso terapêutico , Injeções Intradérmicas
7.
Int J Mol Sci ; 24(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37628840

RESUMO

To develop novel mineral-filled composites and assess their enhanced properties (stiffness, a good balance between mechanical strength and impact resistance, greater temperature stability), a high-impact polypropylene copolymer (PPc) matrix containing an elastomeric discrete phase was melt mixed with natural CaSO4 ß-anhydrite II (AII) produced from gypsum rocks. First, in a prior investigation, the PPc composites filled with AII (without any modification) displayed enhanced stiffness, which is correlated with the relative content of the filler. The tensile and impact strengths dramatically decreased, especially at high filling (40 wt.%). Therefore, two key methods were considered to tune up their properties: (a) the ionomeric modification of PPc composites by reactive extrusion (REx) with zinc diacrylate (ZA), and (b) the melt mixing of PPc with AII surface modified with ethylenebis(stearamide) (EBS), which is a multifunctional processing/dispersant additive. The properties of composites produced with twin-screw extruders (TSEs) were deeply assessed in terms of morphology, mechanical, and thermal performance, including characterizations under dynamic mechanical solicitations at low and high temperatures. Two categories of products with distinct properties are obtained. The ionomeric modification by Rex (evaluated by FTIR) led to composites characterized by remarkable thermal stability, a higher temperature of crystallization, stronger interfacial interactions, and therefore noticeable mechanical properties (high tensile strength (i.e., 28 MPa), increased stiffness, moderate (3.3 kJ/m2) to good (5.0 kJ/m2) impact resistance) as well as advanced heat deflection temperature (HDT). On the other hand, the surface modification of AII with EBS facilitated the dispersion and debonding of microparticles, leading to composites revealing improved ductility (strain at break from 50% to 260%) and enhanced impact properties (4.3-5.3 kJ/m2), even at high filling. Characterized by notable mechanical and thermal performances, high whiteness, and a good processing ability, these new PPc-AII composites may be tailored to meet the requirements of end-use applications, ranging from packaging to automotive components.


Assuntos
Micropartículas Derivadas de Células , Polipropilenos , Parafusos Ósseos , Sulfato de Cálcio , Cristalização , Polímeros
8.
Medicina (Kaunas) ; 59(5)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37241116

RESUMO

Pelvic venous insufficiency (PVI) is frequently associated with symptoms of abdominal pain or discomfort that is overlooked or under-diagnosed in women. Despite the fact that pelvic venous insufficiency in men is very well documented, its occurrence in women needs to be further studied. Patients with pelvic varicose veins undergo a long and inconclusive diagnostic work-up before the exact cause of the symptoms is identified. Gonadal venous insufficiency (GVI) is a condition that can present acutely, leading to diagnostic challenges. We present a case report of a 47-year-old female with acute abdominal pain and GVI, where endovascular embolization was used for successful treatment. The patient was diagnosed with GVI based on imaging findings of an enlarged left ovarian vein with retrograde flow and dilated pelvic veins seen on magnetic resonance imaging (MRI) with contrast material. Due to the severity of her symptoms and imaging findings, endovascular embolization was chosen as the treatment modality. The embolization was successful, and the patient's symptoms resolved completely. This case highlights the challenge of diagnosing GVI with acute clinical expression and the potential benefits of endovascular embolization as a treatment option. Further studies are needed to determine the optimal management strategies for acute GVI, but endovascular embolization should be considered a safe and effective option. At the same time, we present a short review of the recent literature data related to this topic.


Assuntos
Abdome Agudo , Varizes , Insuficiência Venosa , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Abdome Agudo/complicações , Insuficiência Venosa/complicações , Insuficiência Venosa/diagnóstico , Insuficiência Venosa/terapia , Varizes/complicações , Varizes/terapia , Varizes/diagnóstico , Pelve , Dor Abdominal , Resultado do Tratamento
9.
Polymers (Basel) ; 15(4)2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36850083

RESUMO

Polypropylene (PP) is one of the most versatile polymers widely used in packaging, textiles, automotive, and electrical applications. Melt blending of PP with micro- and/or nano-fillers is a common approach for obtaining specific end-use characteristics and major enhancements of properties. The study aims to develop high-performance composites by filling PP with CaSO4 ß-anhydrite II (AII) issued from natural gypsum. The effects of the addition of up to 40 wt.% AII into PP matrix have been deeply evaluated in terms of morphology, mechanical and thermal properties. The PP-AII composites (without any modifier) as produced with internal mixers showed enhanced thermal stability and stiffness. At high filler loadings (40% AII), there was a significant decrease in tensile strength and impact resistance; therefore, custom formulations with special reactive modifiers/compatibilizers (PP functionalized/grafted with maleic anhydride (PP-g-MA) and zinc diacrylate (ZnDA)) were developed. The study revealed that the addition of only 2% ZnDA (able to induce ionomeric character) leads to PP-AII composites characterized by improved kinetics of crystallization, remarkable thermal stability, and enhanced mechanical properties, i.e., high tensile strength, rigidity, and even rise in impact resistance. The formation of Zn ionomers and dynamic ionic crosslinks, finer dispersion of AII microparticles, and better compatibility within the polyolefinic matrix allow us to explain the recorded increase in properties. Interestingly, the PP-AII composites also exhibited significant improvements in the elastic behavior under dynamic mechanical stress and of the heat deflection temperature (HDT), thus paving the way for engineering applications. Larger experimental trials have been conducted to produce the most promising composite materials by reactive extrusion (REx) on twin-screw extruders, while evaluating their performances through various methods of analysis and processing.

10.
Polymers (Basel) ; 14(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36432967

RESUMO

Concerning new polylactide (PLA) applications, the study investigates the toughening of PLA-CaSO4 ß-anhydrite II (AII) composites with bio-sourced tributyl citrate (TBC). The effects of 5-20 wt.% TBC were evaluated in terms of morphology, mechanical and thermal properties, focusing on the enhancement of PLA crystallization and modification of glass transition temperature (Tg). Due to the strong plasticizing effects of TBC (even at 10%), the plasticized composites are characterized by significant decrease of Tg and rigidity, increase of ductility and impact resistance. Correlated with the amounts of plasticizer, a dramatic drop in melt viscosity is also revealed. Therefore, for applications requiring increased viscosity and enhanced melt strength (extrusion, thermoforming), the reactive modification, with up to 1% epoxy functional styrene-acrylic oligomers, was explored to enhance their rheology. Moreover, larger quantities of products were obtained by reactive extrusion (REX) and characterized to evidence their lower stiffness, enhanced ductility, and toughness. In current prospects, selected samples were tested for the extrusion of tubes (straws) and films. The migration of plasticizer was not noted (at 10% TBC), whereas the mechanical and thermal characterizations of films after two years of aging evidenced a surprising preservation of properties.

11.
J Clin Med ; 11(17)2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36078958

RESUMO

Objective: The presentation of cryostripping as an alternative procedure useful in venous insufficiency treatment. Methods: This retrospective study presents the results of 1087 operated patients, including follow-ups. Cryostripping was practised in all mentioned cases. Patient follow-up was performed at one week, one month, and six months postoperatively by clinical examination, Doppler ultrasonography, CIVIQ-20 and r-VCSS questionnaires. Outcomes, complications, surgery and hospitalisation period, and benefits of the method were analysed. Results: Generally, good functional and aesthetic outcomes defined by clinical symptom remission, absence of insufficient veins on Doppler ultrasonography, QoL and r-VCSS improvement (p < 0.001) were obtained. Complications included bruising ⌀ < 2 cm (32.38%), haematoma (8.92%), saphenous nerve injury (3.49%), deep vein thrombosis (0.18%). Recurrence was noted in 2.94% cases. Mean duration of procedure was 42 ± 12.5 min, mean duration of hospitalisation was 1.05 ± 0.36 days. Compared to high ligation and conventional stripping, the postoperative complications were reduced; compared to other minimally invasive procedures, the costs were reduced. Conclusions: Cryostripping seems to combine the radicality and efficacy of the stripping technique with the cosmetic advantage of the endothermal procedures, being an effective therapeutic method perfectly adapted to the economic conditions of middle-income countries health system. It is also suitable as day-case surgery.

12.
Exp Ther Med ; 24(3): 571, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35978924

RESUMO

Chronic venous disease (CVD) is a frequently encountered disease that progresses with age. Although the principal method of evaluation and diagnosis is Doppler ultrasound, routine laboratory tests may be an easier and more accessible way to evaluate CVD progression. The present retrospective study evaluated the laboratory results of 256 patients diagnosed with CVD. According to the Clinical, Etiological, Anatomical and Pathophysiological classification, depending on the CVD stage, patients were stratified into three groups: Group 1 (C2-C3; mild disease), Group 2 (C4; moderate to severe disease) and Group 3 (C5-C6; severe disease). The considered parameters were age, red blood cell count (RBC), white blood cell count (WBC) and platelet count (PLT), percentage of neutrophils and lymphocytes, neutrophil-to-lymphocyte ratio (NLR), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fibrinogen, prothrombin time (in percentages and seconds), internal normalized ratio, activated partial thromboplastin time, creatine kinase (CK), CK myocardial band, alanine transaminase, aspartate transaminase, total bilirubin and urea. No significant differences among the groups were noted in RBC, WBC, PLT and coagulation factors; on the other hand, inflammatory markers exhibited differences among the groups. Several differences were observed in hepatic, metabolic and muscle tissue markers. Intraluminal thrombus formation in the case of varicose veins (thrombophlebitis) may be due to conditions of turbulent flow, stasis and endothelial inflammation, rather than hypercoagulability. The results of the present study confirmed the implication of inflammatory factors in pathophysiological modifications, including thickening of venous walls and valvular modification, as well as the appearance of intraluminal thrombi and trophic lesions. NLR, ESR, CRP and fibrinogen were increased with CVD progression and may be considered useful markers in evaluating CVD progression. Simple blood tests may provide phlebologists with additional insight for the management of those patients.

13.
Polymers (Basel) ; 14(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35745936

RESUMO

The melt-mixing of polylactide (PLA) with micro- and/or nanofillers is a key method used to obtain specific end-use characteristics and improvements of properties. So-called "insoluble" CaSO4 (CS) ß-anhydrite II (AII) is a mineral filler recently considered for the industry of polymer composites. First, the study proves that AII made from natural gypsum by a specifically thermal treatment is highly stable compared to other CS forms. Then, PLAs of different isomer purity and molecular weights (for injection molding (IM) and extrusion), have been used to produce "green" composites filled with 20-40 wt.% AII. The composites show good thermal and mechanical properties, accounting for the excellent filler dispersion and stability. The stiffness of composites increases with the amount of filler, whereas their tensile strength is found to be dependent on PLA molecular weights. Interestingly, the impact resistance is improved by adding 20% AII into all investigated PLAs. Due to advanced kinetics of crystallization ascribed to the effects of AII and use of a PLA grade of high L-lactic acid isomer purity, the composites show after IM an impressive degree of crystallinity (DC), i.e., as high as 50%, while their Vicat softening temperature is remarkably increased to 160 °C, which are thermal properties of great interest for applications requiring elevated rigidity and heat resistance.

14.
Materials (Basel) ; 14(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34576386

RESUMO

In the category of biopolymers, polylactide or polylactic acid (PLA) is one of the most promising candidates considered for future developments, as it is not only biodegradable under industrial composting conditions, but it is produced from renewable natural resources. The modification of PLA through the addition of nanofillers is considered as a modern approach to improve its main characteristic features (mechanical, thermal, barrier, etc.) and to obtain specific end-use properties. Iron oxide nanoparticles (NPs) of low dimension (10-20 nm) such as magnetite (Fe3O4), exhibit strong magnetization in magnetic field, are biocompatible and show low toxicity, and can be considered in the production of polymer nanocomposites requiring superparamagnetic properties. Accordingly, PLA was mixed by melt-compounding with 4-16 wt.% magnetite NPs. Surface treatment of NPs with a reactive polymethylhydrogensiloxane (MHX) was investigated to render the nanofiller water repellent, less sensitive to moisture and to reduce the catalytic effects at high temperature of iron (from magnetite) on PLA macromolecular chains. The characterization of nanocomposites was focused on the differences of the rheology and morphology, modification, and improvements in the thermal properties using surface treated NPs, while the superparamagnetic behavior was confirmed by VSM (vibrating sample magnetometer) measurements. The PLA-magnetite nanocomposites had strong magnetization properties at low magnetic field (values close to 70% of Mmax at H = 0.2 T), while the maximum magnetic signal (Mmax) was mainly determined by the loading of the nanofiller, without any significant differences linked to the surface treatment of MNPs. These bionanocomposites showing superparamagnetic properties, close to zero magnetic remanence, and coercivity, can be further produced at a larger scale by melt-compounding and can be designed for special end-use applications, going from biomedical to technical areas.

15.
Molecules ; 26(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918508

RESUMO

Due to the added value conferred by zinc oxide (ZnO) nanofiller, e.g., UV protection, antibacterial action, gas-barrier properties, poly(lactic acid) (PLA)-ZnO nanocomposites show increased interest for utilization as films, textile fibers, and injection molding items. The study highlights the beneficial effects of premixing ZnO in PLA under given conditions and its use as masterbatch (MB), a very promising alternative manufacturing technique. This approach allows reducing the residence time at high processing temperature of the thermo-sensitive PLA matrix in contact of ZnO nanoparticles known for their aptitude to promote degradation effects onto the polyester chains. Various PLA-ZnO MBs containing high contents of silane-treated ZnO nanoparticles (up to 40 wt.% nanofiller specifically treated with triethoxycaprylylsilane) were produced by melt-compounding using twin-screw extruders. Subsequently, the selected MBs were melt blended with pristine PLA to produce nanocomposite films containing 1-3 wt.% ZnO. By comparison to the more traditional multi-step process, the MB approach allowed the production of nanocomposites (films) having improved processing and enhanced properties: PLA chains displaying higher molecular weights, improved thermal stability, fine nanofiller distribution, and thermo-mechanical characteristic features, while the UV protection was confirmed by UV-vis spectroscopy measurements. The MB alternative is viewed as a promising flexible technique able to open new perspectives to produce more competitive multifunctional PLA-ZnO nanocomposites.

16.
Pharmaceutics ; 12(1)2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31936742

RESUMO

The influence of excipients on the stability of sodium levothyroxine pentahydrate (LTSS) under ambient conditions and thermal stress was evaluated. Since LTSS is a synthetic hormone with a narrow therapeutic index, the interactions of LTSS with excipients can lead to a drastic diminution of therapeutic activity. Ten commonly used pharmaceutical excipients with different roles in solid formulations were chosen as components for binary mixtures containing LTSS, namely, starch, anhydrous lactose, D-mannitol, D-sorbitol, gelatin, calcium lactate pentahydrate, magnesium stearate, methyl 2-hydroxyethyl cellulose (Tylose), colloidal SiO2 (Aerosil) and talc. As investigational tools, universal attenuated total reflectance- Fourier transform infrared spectroscopy UATR-FTIR spectroscopy and thermal analysis were chosen and used as follows: UATR-FTIR spectra were drawn up for samples kept under ambient conditions, while thermoanalytical tools (TG/DTG/HF data) were chosen to evaluate the inducing of interactions during thermal stress. The corroboration of instrumental results led to the conclusion that LTSS is incompatible with lactose, mannitol and sorbitol, and these excipients should not be considered in the development of new generic solid formulations.

17.
Dis Markers ; 2017: 5241012, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29200598

RESUMO

Cardiovascular diseases represent important complications in rheumatoid arthritis (RA) patients, generated by an accelerated atherosclerosis. The aim of this study is represented by the assessment of the correlations between serum levels of vitamin D, disease activity, and endothelial dysfunction in patients with early RA. Material and Methods. The study was performed on a group of 35 patients with early RA and 35 healthy subjects matched for age and gender, as controls. In all studied subjects, the following were determined: inflammatory markers, insulin resistance, vitamin D levels, and endothelial dysfunction. Statistical analysis were performed using the Student's t-test and the Pearson's test. p values of less than 0.05 were considered statistically significant. Results. The group of patients with RA patients presented inflammation, low levels of vitamin D, elevated insulin resistance, and reduced flow-mediated vasodilation, statistically significant compared to the control group (p < 0.00001). Significant inverse correlations between the levels of 25(OH) vitamin D and DAS28, respective insulin resistance, and significant positive correlation between 25(OH) vitamin D and endothelial function were demonstrated. Conclusion. In early RA patients with moderate and high disease activity, low serum levels of vitamin D were associated with disease activity, increased insulin resistance, and endothelial dysfunction.


Assuntos
Artrite Reumatoide/sangue , Doenças Cardiovasculares/sangue , Endotélio Vascular/patologia , Vitamina D/sangue , Idoso , Artrite Reumatoide/complicações , Artrite Reumatoide/patologia , Biomarcadores/sangue , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/patologia , Feminino , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Vasodilatação
18.
Adv Drug Deliv Rev ; 107: 17-46, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27085468

RESUMO

Poly(lactic acid) or polylactide (PLA), a biodegradable polyester produced from renewable resources, is used for various applications (biomedical, packaging, textile fibers and technical items). Due to its inherent properties, PLA has a key-position in the market of biopolymers, being one of the most promising candidates for further developments. Unfortunately, PLA suffers from some shortcomings, whereas for the different applications specific end-use properties are required. Therefore, the addition of reinforcing fibers, micro- and/or nanofillers, and selected additives within PLA matrix is considered as a powerful method for obtaining specific end-use characteristics and major improvements of properties. This review highlights recent developments, current results and trends in the field of composites based on PLA. It presents the main advances in PLA properties and reports selected results in relation to the preparation and characterization of the most representative PLA composites. To illustrate the possibility to design the properties of composites, a section is devoted to the production and characterization of innovative PLA-based products filled with thermally-treated calcium sulfate, a by-product from the lactic acid production process. Moreover, are emphasized the last tendencies strongly evidenced in the case of PLA, i.e., the high interest to diversify its uses by moving from biomedical and packaging (biodegradation properties, "disposables") to technical applications ("durables").


Assuntos
Poliésteres/química , Poliésteres/síntese química , Biopolímeros/química , Ácido Láctico/síntese química , Ácido Láctico/química
19.
Biomacromolecules ; 13(10): 3283-91, 2012 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-22967047

RESUMO

This study reports the effect of light on PLA/ZnO nanocomposites films produced by melt-extrusion. The attention focused on the discrimination between the photocatalytic degradation of PLA provoked by ZnO and the UV screening effect of the ZnO nanoparticles. The chemical modifications of PLA induced by UV light irradiation were analyzed using infrared spectroscopy and completed through the analysis of the low-molecular-weight photoproducts using IC and SPME and the characterization of chain scissions with SEC. A comprehensive mechanism for the photooxidation of PLA was then proposed. The results indicated that the photocatalytic activity of ZnO nanoparticles induces the oxidation of PLA. Because ZnO limits the penetration of light inside the samples, this effect mainly concerns the first micrometers at the surface of the exposed samples. Cross-sectional analysis using micro-IR and ATR-IR spectroscopies was performed to highlight the degradation profile in the PLA/ZnO nanocomposites.


Assuntos
Nanocompostos/química , Poliésteres/química , Óxido de Zinco/química , Tamanho da Partícula , Processos Fotoquímicos , Propriedades de Superfície , Raios Ultravioleta
20.
Phys Chem Chem Phys ; 14(35): 12301-8, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22858912

RESUMO

The crystallization of PLA-silane surface-treated ZnO nanocomposites was investigated by DSC and compared to that of neat PLA. Several modes of crystallization were considered: isothermal and non-isothermal cold crystallization and also isothermal and non-isothermal melt crystallization. The kinetics of cold crystallization were studied using different methods, namely the Avrami and Ozawa-Flynn-Wall models, to calculate activation energies and kinetic constants. In contrast to what is typically observed when the foreign particles are added in a polymer matrix, the silane surface-treated ZnO delayed the crystallization of PLA and made it more difficult to start. The nucleation activity of the ZnO nanoparticles, ϕ, was calculated and found to be greater than 1 (ϕ = 1.7). This indicated that ZnO played an anti-nucleating role in the crystallization of PLA nanocomposites. This effect has been linked mainly to the interactions between the silane groups onto the surface of nanoparticles and PLA macromolecules. These interactions which reduce the mobility of polymer chains have been evidenced by rheological experiments.


Assuntos
Ácido Láctico/química , Nanocompostos/química , Polímeros/química , Silanos/química , Óxido de Zinco/química , Varredura Diferencial de Calorimetria , Cristalização , Poliésteres , Propriedades de Superfície
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