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1.
iScience ; 25(6): 104409, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35663021

RESUMO

Non-human primates (NHP) are widely used for the pre-clinical assessment of antiretrovirals (ARVs) for HIV treatment and prevention. However, the utility of these models is questionable given the differences in ARV pharmacology between humans and macaques. Here, we report a model based on ex vivo ARV exposure and the challenge of mucosal tissue explants to define pharmacological differences between NHPs and humans. For colorectal and cervicovaginal explants in both species, high concentrations of tenofovir (TFV) and maraviroc were predictive of anti-viral efficacy. However, their combinations resulted in increased inhibitory potency in NHP when compared to human explants. In NHPs, higher TFV concentrations were measured in colorectal versus cervicovaginal explants (p = 0.042). In humans, this relationship was inverted with lower levels in colorectal tissue (p = 0.027). TFV-resistance caused greater loss of viral fitness for HIV-1 than SIV. This, tissue explants provide an important bridge to refine and appropriately interpret NHP studies.

2.
Microb Ecol ; 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35654854

RESUMO

Ongoing global warming is expected to alter temperature-dependent processes. Nevertheless, how co-occurring local drivers will influence temperature sensitivity of plant litter decomposition in lotic ecosystems remains uncertain. Here, we examined the temperature sensitivity of microbial-mediated decomposition, microbial respiration, fungal biomass and leaf nutrients of two plant species varying in litter quality. We also assessed whether the type of microbial community and stream water characteristics influence such responses to temperature. We incubated alder (Alnus glutinosa) and eucalypt (Eucalyptus globulus) litter discs in three streams differing in autumn-winter water temperature (range 4.6-8.9 °C). Simultaneously, in laboratory microcosms, litter discs microbially conditioned in these streams were incubated at 5, 10 and 15 °C with water from the conditioning stream and with a water control from an additional stream. Both in the field and in the laboratory, higher temperatures enhanced litter decomposition rates, except for eucalypt in the field. Leaf quality modified the response of decomposition to temperature in the field, with eucalypt leaf litter showing a lower increase, whereas it did not in the laboratory. The origin of microbial community only affected the decomposition rates in the laboratory, but it did not modify the response to temperature. Water quality only defined the phosphorus content of the leaf litter or the fungal biomass, but it did not modify the response to temperature. Our results suggest that the acceleration in decomposition by global warming will be shaped by local factors, mainly by leaf litter quality, in headwater streams.

3.
Br J Pharmacol ; 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35726496

RESUMO

BACKGROUND AND PURPOSE: Interstitial lung disease (ILD) is the main cause of mortality in systemic sclerosis (SSc) and current therapies available are of low efficacy or high toxicity. Thus, the identification of innovative less toxic and high efficacy therapeutic approaches to ILD treatment is a crucial point. P-selectin Glycoprotein Ligand-1 (PSGL-1) interaction with P-selectin initiates leukocyte extravasation and the lack of its expression brings to SSc-like syndrome with high incidence of ILD in aged mice. EXPERIMENTAL APPROACH: Aged PSGL-1-/- mice were used to assay the therapeutic efficacy of an innovative nanotherapy with everolimus (Ev), included in liposomes decorated with high MW hyaluronic acid (LipHA+Ev) and administrated intratracheally to specifically target CD44-expressing lung cells. KEY RESULTS: PSGL-1-/- mice had increased number of CD45+ and CD45- cells, including alveolar and interstitial macrophages, eosinophils, granulocytes and NK cells, and elevated number of myofibroblasts in broncoalveolar lavage (BAL). CD45+ and CD45- cells expressing proinflammatory and profibrotic cytokines were also increased. PSGL-1-/- mice lung histopathology showed increased immune cell infiltration and apoptosis and exacerbated interstitial and peribronchial fibrosis. Targeted nanotherapy with LipHA+Ev reduced BAL number of myofibroblast, cells producing proinflammatory and profibrotic cytokines, and the degree of lung inflammation at histology. LipHA+Ev treatment also provided an important decrease in severity of peribronchial and interstitial lung fibrosis from moderate to mild injury score. CONCLUSIONS AND IMPLICATIONS: Our preclinical study in PSGL-1-/- mice indicates that targeted nanotherapy with LipHA+Ev represents an effective treatment for SSc-ILD, reducing the number of inflammatory and fibrotic cells in BAL and reducing inflammation and fibrosis in lungs.

4.
Carbohydr Polym ; 291: 119622, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698349

RESUMO

The comprehension of the mechanism entailing efficient solvation of cyclodextrins (CD) by green solvents is of great relevance to boost environmentally sustainable usages of smart supramolecular systems. Here, 1-ethyl-3-methylimidazolium acetate, an ecofriendly ionic liquid (IL), is considered as an excellent solvent for native CDs. This IL efficiently dissolves up to 40 wt.% ß- and γ-CD already at ambient temperature and X-ray scattering indicates that CDs do not tend to detrimental flocculation under these drastic concentration conditions. Simulation techniques reveal the intimate mechanism of CD solvation by the ionic species: while the strong hydrogen bonding acceptor acetate anion interacts with CD's hydroxyl groups, the imidazolium cation efficiently solvates the hydrophobic CD walls via dispersive interactions, thus hampering CD's hydrophobic driven flocking. Overall the amphiphilic nature of the proposed IL provides an excellent solvation environment for CDs, through the synergic action of its components.


Assuntos
Ciclodextrinas , Líquidos Iônicos , Imidazóis/química , Líquidos Iônicos/química , Solubilidade , Solventes/química
5.
Front Cell Dev Biol ; 10: 839813, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646913

RESUMO

LGMDD2 is a rare form of muscular dystrophy characterized by one of the three heterozygous deletions described within the TNPO3 gene that result in the addition of a 15-amino acid tail in the C-terminus.TNPO3 is involved in the nuclear import of splicing factors and acts as a host cofactor for HIV-1 infection by mechanisms not yet deciphered. Further characterization of the crosstalk between HIV-1 infection and LGMDD2 disease may contribute to a better understanding of both the cellular alterations occurring in LGMDD2 patients and the role of TNPO3 in the HIV-1 cycle. To this regard, transcriptome profiling of PBMCs from LGMDD2 patients carrying the deletion c.2771delA in the TNPO3 gene was compared to healthy controls. A total of 545 differentially expressed genes were detected between LGMDD2 patients and healthy controls, with a high representation of G protein-coupled receptor binding chemokines and metallopeptidases among the most upregulated genes in LGMDD2 patients. Plasma levels of IFN-ß and IFN-γ were 4.7- and 2.7-fold higher in LGMDD2 patients, respectively. An increase of 2.3-fold in the expression of the interferon-stimulated gene MxA was observed in activated PBMCs from LGMDD2 patients after ex vivo HIV-1 pseudovirus infection. Thus, the analysis suggests a pro-inflammatory state in LGMDD2 patients also described for other muscular dystrophies, that is characterized by the alteration of IL-17 signaling pathway and the consequent increase of metallopeptidases activity and TNF response. In summary, the increase in interferons and inflammatory mediators suggests an antiviral environment and resistance to HIV-1 infection but that could also impair muscular function in LGMDD2 patients, worsening disease evolution. Biomarkers of disease progression and therapeutic strategies based on these genes and mechanisms should be further investigated for this type of muscular dystrophy.

7.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35569542

RESUMO

INTRODUCTION: Inadequate social support is associated with higher mortality both in the general population and in patients with chronic diseases. There are no studies that have described social support in liver cirrhosis and its impact on prognosis. OBJECTIVES: To analyze the impact social support has in the survival of patients with decompensated cirrhosis. METHODS: Prospective multicentric cohort study (2016-2019). Patients with decompensated liver cirrhosis were included. Epidemiological, clinical and social variables were collected, using the validated Medical Outcomes Study Social Support Survey, with a 12-month follow-up. RESULTS: A total of 127 patients were included, of which 79.5% were men. The most common etiology of cirrhosis was alcohol (74.8%), mean age was 60 years (SD 10.29), mean MELD was 15.6 (SD 6.3) and most of the patients had a Child-Pugh B (53.5%) or C (35.4%). In the assessment of social support, we observed that most of the patients (92.2%) had adequate global support. At the end of the follow-up (median 314 days), 70.1% of the patients survived. The 1-year survival rate in patients with inadequate global social support was 30%, compared to 73.5% in the presence of social support. In multivariate Cox regression analysis, inadequate social support predicted survival with an adjusted HR of 5.5 (95% CI 2,3-13,4) independently of MELD (HR 1.1, 95% CI 1-1.2), age (HR 1, 95% CI 1-1.1) and hepatocarcinoma (HR 10.6, 95% CI 4.1-27.4). CONCLUSION: Adequate social support improves survival in liver cirrhosis, independently of clinical variables. Social intervention strategies should be considered for their management.

8.
Elife ; 112022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35559731

RESUMO

Dyskeratosis congenita (DC) is a rare genetic disorder characterized by deficiencies in telomere maintenance leading to very short telomeres and the premature onset of certain age-related diseases, including pulmonary fibrosis (PF). PF is thought to derive from epithelial failure, particularly that of type II alveolar epithelial (AT2) cells, which are highly dependent on Wnt signaling during development and adult regeneration. We use human induced pluripotent stem cell-derived AT2 (iAT2) cells to model how short telomeres affect AT2 cells. Cultured DC mutant iAT2 cells accumulate shortened, uncapped telomeres and manifest defects in the growth of alveolospheres, hallmarks of senescence, and apparent defects in Wnt signaling. The GSK3 inhibitor, CHIR99021, which mimics the output of canonical Wnt signaling, enhances telomerase activity and rescues the defects. These findings support further investigation of Wnt agonists as potential therapies for DC-related pathologies.


Assuntos
Disceratose Congênita , Células-Tronco Pluripotentes Induzidas , Telomerase , Células Epiteliais Alveolares/metabolismo , Disceratose Congênita/genética , Disceratose Congênita/patologia , Quinase 3 da Glicogênio Sintase , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Mutação , Telomerase/genética , Telomerase/metabolismo , Telômero/metabolismo
9.
J Clin Med ; 11(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35566662

RESUMO

The main objectives of this work were to assess the efficiency, ease-of-use, and general performance of a novel osseoshaping tool based on first-user clinical experiences and to compare these observations with preclinical data generated in rodents using a miniaturized version of the instrument. All patients selected for the surgery presented challenging clinical conditions in terms of the quality and/or quantity of the available bone. The presented data were collected during the implant placement of 15 implants in 7 patients, and included implant recipient site (bone quality and quantity) and ridge evaluation, intra-operative handling of the novel instrument, and the evaluation of subsequent implant insertion. The instrument was easy to handle and was applied without any complications during the surgical procedure. Its use obviated the need for multiple drills and enabled adequate insertion torque in all cases. This biologically driven innovation in implant site preparation shows improvements in preserving vital anatomical and cellular structures as well as simplifying the surgical protocol with excellent ease-of-use and handling properties.

10.
J Clin Med ; 11(9)2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35566685

RESUMO

We aimed to examine the prevalence of suicidal ideation in patients with chronic obstructive pulmonary disease (COPD) and the association between demographic and clinical variables and the occurrence of suicidal thoughts. This was a cross-sectional study. Sociodemographic and clinical data were recorded, and questionnaires were used to assess depressive symptoms (Beck Depression Inventory), comorbidities (Charlson Index), cognitive performance (Mini Mental State Examination), and quality of life (EuroQoL-5 dimensions and CAT). Specific questions about suicide-related behavior were included. Multivariate logistic regression analysis identified the significant factors associated with previous suicidal ideation and suicide attempts. The analysis included 1190 subjects. The prevalence of suicidal ideation and suicide attempts were 12.1% and 2.5%, respectively. Severely depressed patients had the highest prevalence of suicide-related behavior. The adjusted logistic model identified factors significantly associated with suicidal ideation: sex (odds ratio (OR) for women vs. men = 2.722 (95% confidence interval (CI) = 1.771-4.183)), depression score (OR = 1.163 (95% IC = 1.127-1.200)), and Charlson Index (OR 1.228 (95% IC 1.082-1.394)). Suicidal ideation is common in COPD patients, especially in women. While addressing suicidal ideation and suicide prevention, clinicians should first consider the management of depressive symptomatology and the improvement of coping strategies.

11.
J Clin Med ; 11(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35628927

RESUMO

Individuals with oncohematological diseases (OHD) may develop an impaired immune response against vaccines due to the characteristics of the disease or to its treatment. Humoral response against SARS-CoV-2 has been described to be suboptimal in these patients, but the quality and efficiency of the cellular immune response has not been yet completely characterized. In this study, we analyzed the early humoral and cellular immune responses in individuals with different OHD after receiving one dose of an authorized vaccine against SARS-CoV-2. Humoral response, determined by antibodies titers and neutralizing capacity, was overall impaired in individuals with OHD, except for the cohort of chronic myeloid leukemia (CML), which showed higher levels of specific IgGs than healthy donors. Conversely, the specific direct cytotoxic cellular immunity response (DCC) against SARS-CoV-2, appeared to be enhanced, especially in individuals with CML and chronic lymphocytic leukemia (CLL). This increased cellular immune response, developed earlier than in healthy donors, showed a modest cytotoxic activity that was compensated by significantly increased numbers, likely due to the disease or its treatment. The analysis of the immune response through subsequent vaccine doses will help establish the real efficacy of COVID-19 vaccines in individuals with OHD.

12.
Artigo em Inglês | MEDLINE | ID: mdl-35564626

RESUMO

BACKGROUND: Blue spaces have been a key part of human evolution, providing resources and helping economies develop. To date, no studies have been carried out to explore how they may be linked to paediatric oncological diseases. OBJECTIVES: To explore the possible relationship of residential proximity to natural and urban blue spaces on childhood leukaemia. METHODS: A population-based case-control study was conducted in four regions of Spain across the period 2000-2018. A total of 936 incident cases and 5616 controls were included, individually matched by sex, year of birth and place of residence. An exposure proxy with four distances (250 m, 500 m, 750 m, and 1 km) to blue spaces was built using the geographical coordinates of the participants' home residences. Odds ratios (ORs) and 95% confidence intervals (95%CIs) for blue-space exposure were calculated for overall childhood leukaemia, and the acute lymphoblastic (ALL) and acute myeloblastic leukaemia (AML) subtypes, with adjustment for socio-demographic and environmental covariates. RESULTS: A decrease in overall childhood leukaemia and ALL-subtype incidence was found as we came nearer to children's places of residence, showing, for the study as a whole, a reduced incidence at 250 m (odds ratio (OR) = 0.77; 95%CI = 0.60-0.97), 500 m (OR = 0.78; 95%CI = 0.65-0.93), 750 m (OR = 0.80; 95%CI = 0.69-0.93), and 1000 m (OR = 0.84; 95%CI = 0.72-0.97). AML model results showed an increasing incidence at closest to subjects' homes (OR at 250m = 1.06; 95%CI=0.63-1.71). CONCLUSIONS: Our results suggest a possible association between lower childhood leukaemia incidence and blue-space proximity. This study is a first approach to blue spaces' possible effects on childhood leukaemia incidence; consequently, it is necessary to continue studying these spaces-while taking into account more individualised data and other possible environmental risk factors.


Assuntos
Leucemia , Estudos de Casos e Controles , Criança , Feminino , Habitação , Humanos , Incidência , Leucemia/epidemiologia , Leucemia/etiologia , Razão de Chances , Fatores de Risco , Espanha/epidemiologia
13.
J Clin Med ; 11(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35456230

RESUMO

Oncohematological patients show a low immune response against SARS-CoV-2, both to natural infection and after vaccination. Most studies are focused on the analysis of the humoral response; therefore, the information available about the cellular immune response is limited. In this study, we analyzed the humoral and cellular immune responses in nine individuals who received chemotherapy for their oncohematological diseases, as well as consolidation with autologous stem cell transplantation (ASCT), after being naturally infected with SARS-CoV-2. All individuals had asymptomatic or mild COVID-19 and were not vaccinated against SARS-CoV-2. These results were compared with matched healthy individuals who also had mild COVID-19. The humoral response against SARS-CoV-2 was not detected in 6 of 9 oncohematological individuals prior to ASCT. The levels of antibodies and their neutralization capacity decreased after ASCT. Conversely, an enhanced cytotoxic activity against SARS-CoV-2-infected cells was observed after chemotherapy plus ASCT, mostly based on high levels of NK, NKT, and CD8+TCRγδ+ cell populations that were able to produce IFNγ and TNFα. These results highlight the importance of performing analyses not only to evaluate the levels of IgGs against SARS-CoV-2, but also to determine the quality of the cellular immune response developed during the immune reconstitution after ASCT.

14.
Plants (Basel) ; 11(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35448747

RESUMO

Biosilica accumulation in plant tissues is related to the transpiration stream, which in turn depends on water availability. Nevertheless, the debate on whether genetically and environmentally controlled mechanisms of biosilica deposition are directly connected to water availability is still open. We aim at clarifying the system which leads to the deposition of biosilica in Sorghum bicolor, Pennisetum glaucum, and Eleusine coracana, expanding our understanding of the physiological role of silicon in crops well-adapted to arid environments, and simultaneously advancing the research in archaeological and paleoenvironmental studies. We cultivated ten traditional landraces for each crop in lysimeters, simulating irrigated and rain-fed scenarios in arid contexts. The percentage of biosilica accumulated in leaves indicates that both well-watered millet species deposited more biosilica than the water-stressed ones. By contrast, sorghum accumulated more biosilica with respect to the other two species, and biosilica accumulation was independent of the water regime. The water treatment alone did not explain either the variability of the assemblage or the differences in the biosilica accumulation. Hence, we hypothesize that genetics influence the variability substantially. These results demonstrate that biosilica accumulation differs among and within C4 species and that water availability is not the only driver in this process.

15.
Rev Esp Enferm Dig ; 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35240848

RESUMO

Primary aortoesophageal fistula, an abnormal communication between native aorta and oesophagus, is an extremely rare cause of upper gastrointestinal bleeding. The typical symptoms, known as the Chiari´s triad, are only present in 45% of cases. It has a high mortality, so early diagnosis is essential to increase the probability of survival. We present a case report of a patient with massive upper gastrointestinal bleeding due to primary aortoesophageal fistula.

16.
EMBO Mol Med ; 14(4): e14841, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35263037

RESUMO

Small-Cell Lung Cancer (SCLC) is an aggressive neuroendocrine malignancy with a poor prognosis. Here, we focus on the neuroendocrine SCLC subtypes, SCLC-A and SCLC-N, whose transcription addiction was driven by ASCL1 and NEUROD1 transcription factors which target E-box motifs to activate up to 40% of total genes, the promoters of which are maintained in a steadily open chromatin environment according to ATAC and H3K27Ac signatures. This leverage is used by the marine agent lurbinectedin, which preferentially targets the CpG islands located downstream of the transcription start site, thus arresting elongating RNAPII and promoting its degradation. This abrogates the expression of ASCL1 and NEUROD1 and of their dependent genes, such as BCL2, INSM1, MYC, and AURKA, which are responsible for relevant SCLC tumorigenic properties such as inhibition of apoptosis and cell survival, as well as for a part of its neuroendocrine features. In summary, we show how the transcription addiction of these cells becomes their Achilles's heel, and how this is effectively exploited by lurbinectedin as a novel SCLC therapeutic endeavor.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Carbolinas , Compostos Heterocíclicos de 4 ou mais Anéis , Neoplasias Pulmonares , Proteínas Repressoras , Carcinoma de Pequenas Células do Pulmão , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carbolinas/farmacologia , Linhagem Celular Tumoral , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteínas Repressoras/metabolismo , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo
17.
Sci Total Environ ; 829: 154578, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35304152

RESUMO

BACKGROUND: Mammographic density (MD), expressed as percentage of fibroglandular breast tissue, is an important risk factor for breast cancer. Our objective is to investigate the relationship between MD and residential proximity to pollutant industries in premenopausal Spanish women. METHODS: A cross-sectional study was carried out in a sample of 1225 women extracted from the DDM-Madrid study. Multiple linear regression models were used to assess the association of MD percentage (and their 95% confidence intervals (95%CIs)) and proximity (between 1 km and 3 km) to industries included in the European Pollutant Release and Transfer Register. RESULTS: Although no association was found between MD and distance to all industries as a whole, several industrial sectors showed significant association for some distances: "surface treatment of metals and plastic" (ß = 4.98, 95%CI = (0.85; 9.12) at ≤1.5 km, and ß = 3.00, 95%CI = (0.26; 5.73) at ≤2.5 km), "organic chemical industry" (ß = 6.73, 95%CI = (0.50; 12.97) at ≤1.5 km), "pharmaceutical products" (ß = 4.14, 95%CI = (0.58; 7.70) at ≤2 km; ß = 3.55, 95%CI = (0.49; 6.60) at ≤2.5 km; and ß = 3.11, 95%CI = (0.20; 6.01) at ≤3 km), and "urban waste-water treatment plants" (ß = 8.06, 95%CI = (0.82; 15.30) at ≤1 km; ß = 5.28; 95%CI = (0.49; 10.06) at ≤1.5 km; ß = 4.30, 95%CI = (0.03; 8.57) at ≤2 km; ß = 5.26, 95%CI = (1.83; 8.68) at ≤2.5 km; and ß = 3.19, 95%CI = (0.46; 5.92) at ≤3 km). Moreover, significant increased MD was observed in women close to industries releasing specific pollutants: ammonia (ß = 4.55, 95%CI = (0.26; 8.83) at ≤1.5 km; and ß = 3.81, 95%CI = (0.49; 7.14) at ≤2 km), dichloromethane (ß = 3.86, 95%CI = (0.00; 7.71) at ≤2 km), ethylbenzene (ß = 8.96, 95%CI = (0.57; 17.35) at ≤3 km), and phenols (ß = 2.60, 95%CI = (0.21; 5.00) at ≤2.5 km). CONCLUSIONS: Our results suggest no statistically significant relationship between MD and proximity to industries as a whole, although we detected associations with various industrial sectors and some specific pollutants, which suggests that MD could have a mediating role in breast carcinogenesis.


Assuntos
Neoplasias da Mama , Poluentes Ambientais , Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Estudos de Casos e Controles , Estudos Transversais , Poluição Ambiental , Feminino , Humanos , Fatores de Risco
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 272: 120980, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35168033

RESUMO

Using the proper size of nanoparticles as an active substrate, Surface-enhanced Raman scattering (SERS) can provide a reliable technique for detecting and identifying fungi, including Alternaria alternata, Aspergillus flavus, Fusarium verticilliodes, and Aspergillus parasiticus that have been associated to biodeterioration and biodegradation of cultural heritage materials. In this research spherical silver nanoparticles (AgNPs) of average size of 10, 30 and 60 nm were synthesized using the wet chemical method with good yield and their size and shape distributions were examined using small-angle X-ray scattering (SAXS). The protocol for fungi sample preparation proved to be critical for producing high-quality and reproducible SERS spectra. We found that the effect of AgNPs on SERS signal enhancement is size dependent under the same experimental conditions; the SERS intensity of fungal strains using 60 nm achieved up to 2.3x105 enhancement, about twice as intense as those produced with 30 nm, and 10 nm produced a minor broad weak peak barely discernible around 1400 cm-1, similar to the NR spectra profile in the 550-1700 cm-1 spectral region, and the SERS signals using 60 nm showed high reproducibility, with less than 20% variance. Furthermore, we used principal component analysis (PCA) to statistically classify the SERS spectrum into four separate clusters with 99 percent variability so that the four fungal strains could be clearly detected and identified. The SERS technique, in combination with the PCA developed in this study, provides a simple, rapid, accurate, and cost-effective analytical tool for detecting and identifying filamentous fungal strains.


Assuntos
Nanopartículas Metálicas , Prata , Fungos , Reprodutibilidade dos Testes , Espalhamento a Baixo Ângulo , Análise Espectral Raman/métodos , Difração de Raios X
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