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1.
J Dairy Sci ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38788852

RESUMO

Methane is a potent greenhouse gas produced during the ruminal fermentation and is associated with a loss of feed energy. Therefore, efforts to reduce methane emissions have been ongoing in the last decades. Methane production is highly influenced by factors such as the ruminal microbiome and host genetics. Previous studies have proposed to use the ruminal microbiome to reduce long-term methane emissions, as ruminal microbiome composition is a moderately heritable trait and genetic improvement accumulates over time. Lactation stage is another important factor that might influence methane production but potential associations with the ruminal microbiome have not been evaluated previously. This study sought to examine the changes in ruminal microbiome over the lactation period of primiparous Holstein cows differing in methane intensity and estimate the heritability of the abundance of relevant microorganisms. Ruminal content samples from 349 primiparous Holstein cows with 14 - 378 d in milk were collected from May 2018 to June 2019. Methane intensity (MI) of each cow was calculated as methane concentration/milk yield. Up to 64 taxonomic features (TF) from 20 phyla had a significant differential abundance between cows with low and high MI early in lactation, 16 TF during mid lactation, and none late in lactation. Taxonomical features within the Firmicutes, Proteobacteria, Melainabacteria, Cyanobacteria, Bacteroidetes and Actinobacteria phyla were associated to low MI, whereas eukaryotic TF and those within the Euryarchaeota, Verrucomicrobia, Kiritimatiellaeota, Lentisphaerae phyla were associated to high MI. Out of the 60 TF that were found to be differentially abundant between early and late lactation in cows with low MI, 56 TF were also significant when cows with low and high MI were compared in the first third of the lactation. In general, microbes associated with low MI were more abundant early in lactation (e.g., Acidaminococcus, Aeromonas and Weimeria genera) and showed low to moderate heritabilities (0.03 to 0.33). These results suggest some potential to modulate the rumen microbiome composition through selective breeding for lower MI. Differences in the ruminal microbiome of cows with extreme MI levels likely result from variations in the ruminal physiology of these cows and were more noticeable early in lactation probably due to important interactions between the host phenotype and environmental factors associated to that period. Our results suggest that the ruminal microbiome evaluated early in lactation may be more precise for MI difference, and hence, this should be considered to optimize sampling periods to establish a reference population in genomic selection scenarios.

3.
J Dairy Sci ; 107(8): 5881-5896, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38522834

RESUMO

Genetic material from rumen microorganisms can be found within the oral cavity, and hence there is potential in using the oral microbiome as a proxy of the ruminal microbiome. Feed intake (FI) influences the composition of rumen microbiota and might directly influence the oral microbiome in dairy cattle. Ruminal content samples (RS) from 29 cows were collected at the beginning of the study and also 42 d later (RS0 and RS42, respectively). Additionally, 18 oral samples were collected through buccal swabbing at d 42 (OS42) from randomly selected cows. Samples were used to characterize and compare the taxonomy and functionality of the oral microbiome using nanopore sequencing and to evaluate the feasibility of using the oral microbiome to estimate FI. Up to 186 taxonomical features were found differentially abundant (DA) between RS and OS42. Similar results were observed when comparing OS42 to RS collected on different days. Microorganisms associated with the liquid fraction of the rumen were less abundant in OS42 because these were probably swallowed after regurgitation. Up to 1,102 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were found to be DA between RS and OS42, and these results differed when comparing time of collection, but DA KEGG pathways were mainly associated with metabolism in both situations. Models based on the oral microbiome and rumen microbiome differed in their selection of microbial groups and biological pathways to predict FI. In the rumen, fiber-associated microorganisms are considered suitable indicators of FI. In contrast, biofilm formers like Gammaproteobacteria or Bacteroidia classes are deemed appropriate proxies for predicting FI from oral samples. Models from RS exhibited some predictive ability to estimate FI, but oral samples substantially outperformed them. The best lineal model to estimate FI was obtained with the relative abundance of taxonomical feature at genera level, achieving an average R2 = 0.88 within the training data, and a root mean square error of 3.46 ± 0.83 (±SD) kg of DM, as well as a Pearson correlation coefficient between observed and estimated FI of 0.48 ± 0.30 in the test data. The results from this study suggest that oral microbiome has potential to predict FI in dairy cattle, and it encourages validating this potential in other populations.


Assuntos
Microbiota , Boca , Rúmen , Animais , Bovinos , Rúmen/microbiologia , Feminino , Boca/microbiologia , Ingestão de Alimentos , Ração Animal
4.
Rev Esp Anestesiol Reanim (Engl Ed) ; 71(3): 171-206, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340791

RESUMO

The Airway Management section of the Spanish Society of Anesthesiology, Resuscitation, and Pain Therapy (SEDAR), the Spanish Society of Emergency Medicine (SEMES), and the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) present the Guide for the comprehensive management of difficult airway in adult patients. Its principles are focused on the human factors, cognitive processes for decision-making in critical situations, and optimization in the progression of strategies application to preserve adequate alveolar oxygenation in order to enhance safety and the quality of care. The document provides evidence-based recommendations, theoretical-educational tools, and implementation tools, mainly cognitive aids, applicable to airway management in the fields of anesthesiology, critical care, emergencies, and prehospital medicine. For this purpose, an extensive literature search was conducted following PRISMA-R guidelines and was analyzed using the GRADE methodology. Recommendations were formulated according to the GRADE methodology. Recommendations for sections with low-quality evidence were based on expert opinion through consensus reached via a Delphi questionnaire.


Assuntos
Manuseio das Vias Aéreas , Humanos , Manuseio das Vias Aéreas/normas , Manuseio das Vias Aéreas/métodos , Medicina de Emergência/normas , Adulto , Intubação Intratraqueal
5.
Rev Esp Anestesiol Reanim (Engl Ed) ; 71(3): 207-247, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340790

RESUMO

The Airway Management section of the Spanish Society of Anesthesiology, Resuscitation, and Pain Therapy (SEDAR), the Spanish Society of Emergency Medicine (SEMES), and the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) present the Guide for the comprehensive management of difficult airway in adult patients. Its principles are focused on the human factors, cognitive processes for decision-making in critical situations, and optimization in the progression of strategies application to preserve adequate alveolar oxygenation in order to enhance safety and the quality of care. The document provides evidence-based recommendations, theoretical-educational tools, and implementation tools, mainly cognitive aids, applicable to airway management in the fields of anesthesiology, critical care, emergencies, and prehospital medicine. For this purpose, an extensive literature search was conducted following PRISMA-R guidelines and was analyzed using the GRADE methodology. Recommendations were formulated according to the GRADE methodology. Recommendations for sections with low-quality evidence were based on expert opinion through consensus reached via a Delphi questionnaire.


Assuntos
Manuseio das Vias Aéreas , Humanos , Manuseio das Vias Aéreas/normas , Manuseio das Vias Aéreas/métodos , Medicina de Emergência/normas , Adulto , Intubação Intratraqueal
8.
Autoimmun Rev ; 22(11): 103441, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37708984

RESUMO

OBJECTIVE: To analyze the effectiveness and safety of intravenous immunoglobulin (IVIG) given in routine care to patients with systemic sclerosis (SSc). METHODS: A retrospective multicenter observational study was conducted in SSc patients treated with IVIG. We collected data on epidemiological parameters and clinical outcomes. Firstly, we assessed changes in organ manifestations during IVIG treatment. Secondly, we analyzed the frequency of adverse effects. The following parameters were collected from baseline to the last follow-up: the patient's weight, modified Rodnan Skin Score (mRSS), modified manual muscle strength scale (MRC), laboratory test(creatine kinase(CK), hemoglobin and protein levels), The University of California Los Angeles Scleroderma Clinical Trials Consortium gastrointestinal tract 2.0 (UCLA GIT 2.0) questionnaire, pulmonary function tests, and echocardiography. RESULTS: Data were collected on 78 patients (82% females; 59% with diffuse SSc). Inflammatory idiopathic myopathy was the most frequent concomitant overlap disease (41%). The time since Raynaud's phenomenon and SSc onset were 8.8 ± 18 and 6.2 ± 6.7 years respectively. The most frequent IVIG indication was myositis (38/78), followed by gastrointestinal (27/78) and cutaneous (17/78) involvement. The median number of cycles given were 5. 54, 53 and 9 patients have been treated previously with glucocorticoids, synthetic disease-modifying antirheumatic drugs and biologic therapies respectively. After IVIG use we found significant improvements in muscular involvement (MRC ≥ 3/5 92% IVIG, p = 0.001 and CK levels from 1149 ± 2026 UI to 217 ± 224 UI, p = 0.02), mRSS (15 ± 12.4 to 13 ± 12.5, p = 0.015) and improvement in total score of UCLA GIT 2.0 (p = 0.05). None Anti-RNA polymerase III patients showed an adequate response in gastrointestinal involvement (0/7) in comparison with other antibodies (0 vs. 25, p = 0,039). Cardiorespiratory involvement remained stable. A total of 12 adverse events were reported with only one withdrawn due to serious adverse effect. CONCLUSIONS: this study suggest that IVIG may improve myositis, gastrointestinal and skin involvement in SSc patients treated in routine care and seems to have a good safety profile.


Assuntos
Miosite , Escleroderma Sistêmico , Feminino , Humanos , Masculino , Imunoglobulinas Intravenosas/uso terapêutico , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/tratamento farmacológico , Estudos Retrospectivos , Pele , Miosite/tratamento farmacológico , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto
9.
Artigo em Inglês | MEDLINE | ID: mdl-37539856

RESUMO

BACKGROUND AND OBJECTIVES: Cypress and olive pollen are the most prevalent sensitizer trees in the Mediterranean area. Some patients exhibit a dual sensitization which has not been well documented yet. To identify the allergens involved in the dual cypress and olive allergy (C+O) and study the relationship between phenotype and allergen sensitization. METHODS: C+O patients were selected. Monosensitized subjects to olive or cypress were used as reference. Specific IgE to whole extracts and purified allergens from olive and cypress were performed. Immunoblotting was done to analyze IgG and IgE-binding using olive polyclonal antibodies and patients' sera, respectively. Mutual immunoblotting inhibition of olive and cypress extracts, and inhibition of cypress extract immunoblotting with olive allergens were performed. Multiple correspondence analysis and hierarchical cluster classifications were conducted to analyze the relationships between C+O clinical presentation (symptoms, seasonality) and allergen profile. RESULTS: C+O patients were clustered in 4 phenotypes. The most frequent one (58.4%) was rhinoconjunctivitis in winter (February) and spring (May), with asthma in 38% of subjects. Ole e 1 and Cup s 1 were the major allergens. Homologous proteins to Ole e 1, Ole e 9 and Ole e 11 in cypress pollen were identified and these olive allergens inhibit IgE-binding to cypress extract. CONCLUSIONS: The exclusive C+O allergy results from co-sensitization to Cup s 1 and Ole e 1, and to cross-reactivity due to Ole e 1-like, Ole e 9-like and Ole e 11-like allergens not described previously, and translates into 4 clinical phenotypes of winter and/or spring or perennial rhinoconjunctivitis with and without asthma.

10.
Rev Clin Esp (Barc) ; 223(8): 461-469, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37454971

RESUMO

BACKGROUND: Emerging evidence suggests that frailty may be a significant predictor of poor outcomes in older individuals hospitalized due to COVID-19. This study aims to determine the prognostic value of frailty on intrahospital patient survival. METHODS: This observational, multicenter, nationwide study included patients aged 70 years and older who were hospitalized due to COVID-19 in Spain between March 1 and December 31, 2020. Patient data were obtained from the SEMI-COVID-19 Registry of the Spanish Society of Internal Medicine. Frailty was assessed using the Clinical Frailty Scale. The primary outcome was hospital survival. Cox proportional hazards models were used to assess predictors of survival. RESULTS: A total of 1,878 participants (52% men and 48% women) were included, with 1,351 (71.9%) survivors and 527 (28.1%) non-survivors. The non-survivor group had higher mean age (83.5 vs. 81 years), comorbidities (6.3 vs. 5.3 points on the Charlson index), degree of dependency (26.8% vs. 12.4% severely dependent patients), and frailty (34.5% vs. 14.7% severely frail patients) compared to survivors. However, there were no differences in terms of sex. Our results demonstrate that a moderate-severe degree of frailty is the primary factor independently associated with shorter survival [HR 2.344 (1.437-3.823; p<0.001) for CFS 5-6 and 3.694 (2.155-6.330; p<0.001) for CFS 7-9]. CONCLUSION: Frailty is the main predictor of adverse outcomes in older patients with COVID-19. The utilization of tools such as the Clinical Frailty Scale is crucial for early detection in this population.


Assuntos
COVID-19 , Fragilidade , Idoso , Masculino , Humanos , Feminino , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Idoso Fragilizado , Avaliação Geriátrica/métodos , Hospitais
11.
Rehabilitacion (Madr) ; 57(4): 100809, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-37399639

RESUMO

INTRODUCTION: Falls are among the most frequent complications following stroke (CVA), and have a negative impact on rehabilitation. OBJECTIVES: To study the incidence, circumstances, and consequences of falls in stroke patients up to 12months after starting outpatient kinetic treatment. MATERIALS AND METHODS: Prospective design, case series. Consecutive sampling. Patients admitted to the day hospital between June 2019 and May 2020. Included: adults with a diagnosis of first supratentorial stroke and functional ambulatory category score ≥3. EXCLUSION CRITERIA: other condition affecting locomotion. MAIN VARIABLES: number of falls, circumstances, and consequences. Clinical, demographic, and functional characteristics were measured. RESULTS: Twenty-one subjects were included, 13 suffered at least one fall. The subjects reported 41 falls: 15 were to the most affected side, 35 inside the home, 28 without the indicated equipment, they were alone when the event occurred on 29 occasions, and in two situations medical assistance was required. There were statistically significant differences (P<.05) in functional performance (balance, gait velocity) between those who fell and those who did not. No significant differences were found between gait endurance and falls. CONCLUSION: More than half suffered a fall, alone, to the weaker side, and without the appropriate equipment. With this information the incidence could be reduced by preventive measures.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adulto , Humanos , Seguimentos , Incidência , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia
12.
Allergy ; 78(9): 2497-2509, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37334557

RESUMO

BACKGROUND: Pru p 3 and Pru p 7 have been implicated as risk factors for severe peach allergy. This study aimed to establish sensitization patterns to five peach components across Europe and in Japan, to explore their relation to pollen and foods and to predict symptom severity. METHODS: In twelve European (EuroPrevall project) and one Japanese outpatient clinic, a standardized clinical evaluation was conducted in 1231 patients who reported symptoms to peach and/or were sensitized to peach. Specific IgE against Pru p 1, 2, 3, 4 and 7 and against Cup s 7 was measured in 474 of them. Univariable and multivariable Lasso regression was applied to identify combinations of parameters predicting severity. RESULTS: Sensitization to Pru p 3 dominated in Southern Europe but was also quite common in Northern and Central Europe. Sensitization to Pru p 7 was low and variable in the European centers but very dominant in Japan. Severity could be predicted by a model combining age of onset of peach allergy, probable mugwort, Parietaria pollen and latex allergy, and sensitization to Japanese cedar pollen, Pru p 4 and Pru p 7 which resulted in an AUC of 0.73 (95% CI 0.73-0.74). Pru p 3 tended to be a risk factor in South Europe only. CONCLUSIONS: Pru p 7 was confirmed as a significant risk factor for severe peach allergy in Europe and Japan. Combining outcomes from clinical and demographic background with serology resulted in a model that could better predict severity than CRD alone.


Assuntos
Hipersensibilidade Alimentar , Prunus persica , Humanos , Prunus persica/efeitos adversos , Hipersensibilidade Alimentar/diagnóstico , Alérgenos , Antígenos de Plantas , Imunoglobulina E , Proteínas de Plantas
13.
Carbohydr Polym ; 316: 120925, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321754

RESUMO

Boronated polymers are in the focus of dynamic functional materials due to the versatility of the B-O interactions and accessibility of precursors. Polysaccharides are highly biocompatible, and therefore, an attractive platform for anchoring boronic acid groups for further bioconjugation of cis-diol containing molecules. We report for the first time the introduction of benzoxaborole by amidation of the amino groups of chitosan improving solubility and introducing cis-diol recognition at physiological pH. The chemical structures and physical properties of the novel chitosan-benzoxaborole (CS-Bx) as well as two phenylboronic derivatives synthesized for comparison, were characterized by nuclear magnetic resonance (NMR), infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering (DLS), rheology and optical spectroscopic methods. The novel benzoxaborole grafted chitosan was perfectly solubilized in an aqueous buffer at physiological pH, extending the possibilities of boronated materials derived from polysaccharides. The dynamic covalent interaction between boronated chitosan and model affinity ligands, was studied by means of spectroscopy methods. A glycopolymer derived from poly(isobutylene-alt-anhydride) was also synthesized to study the formation of dynamic assemblies with benzoxaborole-grafted chitosan. A first approximation to apply fluorescence microscale thermophoresis for the interactions of the modified polysaccharide is also discussed. Additionally, the activity of CSBx against bacterial adhesion was studied.


Assuntos
Quitosana , Quitosana/química , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Polímeros/química , Antibacterianos/química
14.
Rev Clin Esp ; 223(5): 298-309, 2023 May.
Artigo em Espanhol | MEDLINE | ID: mdl-37124999

RESUMO

Objective: This work aimed to compare the characteristics, progress, and prognosis of patients with COPD hospitalized due to COVID-19 in Spain in the first wave with those of the second wave. Material and methods: This is an observational study of patients hospitalized in Spain with a diagnosis of COPD included in the SEMI-COVID-19 registry. The medical history, symptoms, analytical and radiological results, treatment, and progress of patients with COPD hospitalized in the first wave (from March to June 2020) versus those hospitalized in the second wave (from July to December 2020) were compared. Factors associated with poor prognosis, defined as all-cause mortality and a composite endpoint that included mortality, high-flow oxygen therapy, mechanical ventilation, and ICU admission, were analyzed. Results: Of the 21,642 patients in the SEMI-COVID-19 Registry, 6.9% were diagnosed with COPD: 1,128 (6.8%) in WAVE1 and 374 (7.7%) in WAVE2 (p = 0.04). WAVE2 patients presented less dry cough, fever and dyspnea, hypoxemia (43% vs 36%, p < 0.05), and radiological condensation (46% vs 31%, p < 0.05) than WAVE1 patients. Mortality was lower in WAVE2 (35% vs 28.6%, p = 0.01). In the total sample, mortality and the composite outcome of poor prognosis were lower among patients who received inhalation therapy. Conclusions: Patients with COPD admitted to the hospital due to COVID-19 in the second wave had less respiratory failure and less radiological involvement as well as a better prognosis. These patients should receive bronchodilator treatment if there is no contraindication for it.

15.
Rev Clin Esp (Barc) ; 223(5): 298-309, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37028707

RESUMO

OBJECTIVE: This work aimed to compare the characteristics, progress, and prognosis of patients with COPD hospitalized due to COVID-19 in Spain in the first wave with those of the second wave. MATERIAL AND METHODS: This is an observational study of patients hospitalized in Spain with a diagnosis of COPD included in the SEMI-COVID-19 registry. The medical history, symptoms, analytical and radiological results, treatment, and progress of patients with COPD hospitalized in the first wave (from March to June 2020) versus those hospitalized in the second wave (from July to December 2020) were compared. Factors associated with poor prognosis, defined as all-cause mortality and a composite endpoint that included mortality, high-flow oxygen therapy, mechanical ventilation, and ICU admission, were analyzed. RESULTS: Of the 21,642 patients in the SEMI-COVID-19 Registry, 6.9% were diagnosed with COPD: 1128 (6.8%) in WAVE1 and 374 (7.7%) in WAVE2 (p = 0.04). WAVE2 patients presented less dry cough, fever and dyspnea, hypoxemia (43% vs 36%, p < 0.05), and radiological condensation (46% vs 31%, p < 0.05) than WAVE1 patients. Mortality was lower in WAVE2 (35% vs 28.6%, p = 0.01). In the total sample, mortality and the composite outcome of poor prognosis were lower among patients who received inhalation therapy. CONCLUSIONS: Patients with COPD admitted to the hospital due to COVID-19 in the second wave had less respiratory failure and less radiological involvement as well as a better prognosis. These patients should receive bronchodilator treatment if there is no contraindication for it.


Assuntos
COVID-19 , Doença Pulmonar Obstrutiva Crônica , Humanos , SARS-CoV-2 , Espanha , Hospitalização , Estudos Retrospectivos
17.
Artigo em Inglês | MEDLINE | ID: mdl-36811840

RESUMO

BACKGROUND: Amoxicillin-clavulanic acid (AX-CL) is the most consumed betalactam antibiotic worldwide. We aimed to establish the different phenotypes of betalactam allergy in those referring a reaction with AX-CL and to investigate the differences between immediate and non-immediate onset. METHODS: Cross-sectional retrospective study performed at Hospital Clínico San Carlos (HCSC) and Hospital Regional Universitario de Málaga (HRUM) in Spain. Patients reporting reactions with AX-CL who completed the allergy workup between 2017 and 2019 were included. Data of reported reaction and allergy workup were collected. Reactions were classified as immediate and non-immediate with 1hour cut-off point. RESULTS: We included 372 patients (HCSC 208, HRUM 164). There were 90 (24.2%) immediate, 252 (67.7%) non-immediate reactions, and 30 (8.1%) with unknown latency. Allergy to betalactams was ruled-out in 266 (71.5%) and confirmed in 106 patients (28.5%). The final main diagnosis in the overall population were allergy to aminopenicillins (7.3%), to CL (7%), to penicillin (6.5%) and to betalactams (5.9%). Allergy was confirmed in 77.2% and 14.3% of immediate and non-immediate reactions respectively, with a relative risk of 5.06 (95%CI 3.64-7.02) of an allergy diagnosis in those reporting immediate reactions. Only 2/54 patients with late-positive intradermal test (IDT) to CL were diagnosed of CL allergy. CONCLUSION: Allergy diagnosis was confirmed in a minority of the whole study population, but 5 times more frequently in those reporting immediate reactions, making this classification useful in risk stratification. Late-positive IDT for CL has no diagnostic value and its late reading could be retrieved from the diagnosis work-up.

18.
Heliyon ; 9(1): e13049, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36820169

RESUMO

While some previous studies find a positive relationship between income or economic output and the share of renewables in energy consumption, others find a negative relationship. To bridge these seemingly contradictory findings, we test a non-linear relationship between income and the share of renewable energy sources in total energy consumption (REC%) in eight emerging-Asian countries. Using the feasible generalized least squares method and controlling for financial development and capital formation (two variables found in the literature to affect the use of renewable energy), we find a U-shaped relationship between income and the share of renewables in total energy consumption. In other words, at lower income levels, as income (Gross Domestic Product per capita) increases, REC% decreases. Once the income reaches a certain level, the relationship becomes positive. Financial development positively affects REC%. The implications and policy recommendations are presented in light of these findings.

19.
J Mater Chem B ; 11(8): 1628-1653, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36752739

RESUMO

The carboxylic chemical group is a ubiquitous moiety present in amino acids, a ligand for transition metals, a colloidal stabilizer, and a weak acidic ion-exchanger in polymeric resins and given this property, it is attractive for responsive materials or nanopore-based gating applications. As the number of uses increases, subtle requirements are imposed on this molecular group when anchored to various platforms for the functioning of an integrated chemical system. In this context, silica stands as an inert and multipurpose platform that enables the anchoring of multiple chemical entities combined through several orthogonal synthesis methods on the interface. Surface chemical modification relies on the use of organoalkoxysilanes that must meet the demand of tuned chemical properties; this, in turn, urges for innovative approaches for having an improved, but simple, organic toolbox. Starting from commonly available molecular precursors, several approaches have emerged: hydrosilylation, click thiol-ene additions, the use of carbodiimides or the reaction between cyclic anhydrides and anchored amines. In this review, we analyze the importance of the COOH groups in the area of materials science and the commercial availability of COOH-based silanes and present new approaches for obtaining COOH-based organoalkoxide precursors. Undoubtedly, this will attract widespread interest for the ultimate design of highly integrated chemical platforms.


Assuntos
Silanos , Compostos de Sulfidrila , Sílica Gel , Compostos de Sulfidrila/química , Silanos/química
20.
ACS Omega ; 7(49): 44631-44642, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36530317

RESUMO

Poly(amide-triazole) and poly(ester-triazole) synthesized from d-galactose as a renewable resource were applied for the synthesis of nanoparticles (NPs) by the emulsification/solvent evaporation method. The NPs were characterized as stable, spherical particles, and none of their components, including the stabilizer poly(vinyl alcohol), were cytotoxic for normal rat kidney cells. These NPs proved to be useful for the efficient encapsulation of cilostazol (CLZ), an antiplatelet and vasodilator drug currently used for the treatment of intermittent claudication, which is associated with undesired side-effects. In this context, the nanoencapsulation of CLZ was expected to improve its therapeutic administration. The carbohydrate-derived polymeric NPs were designed taking into account that the triazole rings of the polymer backbone could have attractive interactions with the tetrazole ring of CLZ. The activity of the nanoencapsulated CLZ was measured using a matrix metalloproteinase model in a lipopolysaccharide-induced inflammation system. Interestingly, the encapsulated drug exhibited enhanced anti-inflammatory activity in comparison with the free drug. The results are very promising since the stable, noncytotoxic NP systems efficiently reduced the inflammation response at low CLZ doses. In summary, the NPs were obtained through an innovative methodology that combines a carbohydrate-derived synthetic polymer, designed to interact with the drug, ease of preparation, adequate biological performance, and environmentally friendly production.

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