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1.
J Toxicol Environ Health A ; 87(9): 398-418, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38385605

RESUMO

Nanoribbons of imidacloprid, a systemic and chloronicotinyl insecticide, were successfully synthesized by laser-induced fragmentation/exfoliation of imidacloprid powders suspended in water, with widths ranging from 160 to 470 nm, lengths in the micron scale, and thickness of a few atoms layers. The aim of the present study was to examine the effects of acute and chronic exposure to imidacloprid (IMC) bulk and compare its effects with synthesized imidacloprid nanoribbons (IMCNR) on larval and adult viability, developmental time, olfactory capacity, longevity, productivity, and genotoxicity in Drosophila melanogaster. Larvae or adults were exposed at 0.01, 0.02, or 0.03 ppm to IMC or IMCNR. Results demonstrated that IMCNR produced a significant reduction in viability and olfactory ability. IMC did not significantly alter viability and olfactory ability. Similarly, marked differences on longevity were detected between treatment with IMC and IMCNR where the lifespan of males treated with IMC was significantly higher than control while IMCNR produced a reduction. As for productivity, developmental time, and genotoxicity, no marked differences were found between both forms of IMC.


Assuntos
Inseticidas , Nanotubos de Carbono , Nitrocompostos , Animais , Masculino , Drosophila melanogaster/genética , Nanotubos de Carbono/toxicidade , Neonicotinoides/toxicidade , Inseticidas/toxicidade , Larva , Mutação
2.
Drug Dev Ind Pharm ; 45(4): 683-688, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30633576

RESUMO

A possible way of improving the activity and selectivity profile of antitumor agents is to design drug carrier systems employing soluble macromolecules. Thus, four resorcinarene-PAMAM-dendrimer conjugates of chlorambucil with different groups in the lower part of the macrocycle and different length dendritic arms showed a good stability of the chemical link between drug and spacer. Evaluation of the cytotoxicity of the resorcinarene-PAMAM-dendrimer-chlorambucil conjugate employing a sulforhodamine B (SRB) assay in K-562 (human chronic myelogenous leukemia cells) demonstrated that the conjugate was more potent as an antiproliferative agent than chlorambucil.


Assuntos
Antineoplásicos/administração & dosagem , Calixarenos/química , Clorambucila/administração & dosagem , Portadores de Fármacos/química , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Fenilalanina/análogos & derivados , Dendrímeros/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Fenilalanina/química
3.
Rev Med Chil ; 146(8): 831-839, 2018 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-30534860

RESUMO

BACKGROUND: Dipyridamole (DIP) is the most commonly employed pharmacological stressor for myocardial perfusion tomography (SPECT) in patients unable to reach an adequate work load. AIM: To assess the predictive capacity of DIP SPECT on survival. MATERIAL AND METHODS: We included 985 adults aged 66 ±11 years (45% women) with rest and DIP-SPECT. The main indications for the procedure were coronary artery disease (CAD) screening in 66% and known CAD in 33%. Participants were followed up for a median of 65 months (interquartile range 54 to 86 months). During the follow up, 261 deaths were recorded and 98% had a specified cause in their death certificate. RESULTS: Myocardial SPECT was abnormal in 44% of participants. Transient ischemic defects were observed in 34%, fixed defects concordant with infarction in 27% and post-stress systolic dysfunction in 23%. Twenty five percent of deaths were attributable to cardiac or ischemic cause and 22% to cancer. In a bivariate analysis, the hazard ratio (HR) of death of any cause was lower in females and higher in the presence of CAD. The multivariate analysis showed that being older than 46 years increased the HR of death of any cause. In a bivariate analysis, the HR for cardiac death was higher when the myocardial SPECT showed ischemia, necrosis or left ventricular dilation. In the multivariate analysis, post-stress left ventricular systolic function was associated with a lower risk of cardiac death. CONCLUSIONS: An abnormal myocardial SPECT, perfusion abnormalities, left ventricular systolic function or dilation are independent predictors of cardiac death in these participants.


Assuntos
Dipiridamol , Cardiopatias/diagnóstico por imagem , Cardiopatias/mortalidade , Imagem de Perfusão do Miocárdio/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Vasodilatadores , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco
4.
Langmuir ; 32(13): 3199-206, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-27010536

RESUMO

We report the synthesis of Bi nanoparticles (Bi NPs) using the M13 phage as scaffold. The p8 protein of the phage is functionalized with thiol groups of different lengths, and these thiolated regions act as nucleation centers for Bi(3+) ions. The size distribution, shape, and resilience to oxidation of the Bi NPs depend on the length of the thiol group used. The NPs are characterized by high resolution transmission electron microscopy, Raman, and IR spectroscopies, matrix assisted laser desorption/ionization, and optical absorption. These results show that the nanoparticles are crystalline and have a typical diameter of ∼3.0 nm. The method of preparation presented here is reproducible and implies "greener" conditions than those reported elsewhere. To the best of our knowledge, this is the first report of bismuth nanoparticles synthesized by a biomineralization method.


Assuntos
Bacteriófago M13/química , Bismuto/química , Nanopartículas Metálicas/química , Compostos de Sulfidrila/química , Proteínas Virais/química , Materiais Biomiméticos , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Propionatos/química , Análise Espectral Raman , Succinimidas/química , Sulfetos/química
5.
Neurocirugia (Astur) ; 26(5): 241-5, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-25716895

RESUMO

Primary intraosseous meningiomas are considered extradural meningiomas when no dural attachment is present. Most of them arise from the cranial bones and can present either as an osteoblastic or an osteolytic lesion. Osteolytic intraosseous meningiomas are the rarest and very few cases have been reported. Given that many of these may develop signs of malignancy, early histological confirmation is important in order to ensure appropriate treatment. The recommended therapy is surgery, with complete resection whenever possible. We present the case of a large primary intraosseous osteolytic meningioma within the occipital bone, which was completely excised five years ago, currently presenting no signs of recurrence.


Assuntos
Neoplasias Meníngeas/patologia , Meningioma/patologia , Osso Occipital/patologia , Neoplasias Cranianas/patologia , Humanos
6.
Cancers (Basel) ; 16(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38398221

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most prevalent form of renal cancer and its treatment is hindered by a resistance to targeted therapies, immunotherapies and combinations of both. We have reported that the knockdown of the antisense noncoding mitochondrial RNAs (ASncmtRNAs) with chemically modified antisense oligonucleotides induces proliferative arrest and apoptotic death in tumor cells from many human and mouse cancer types. These studies have been mostly performed in vitro and in vivo on commercially available cancer cell lines and have shown that in mouse models tumor growth is stunted by the treatment. The present work was performed on cells derived from primary and metastatic ccRCC tumors. We established primary cultures from primary and metastatic ccRCC tumors, which were subjected to knockdown of ASncmtRNAs in vitro and in vivo in an orthotopic xenograft model in NOD/SCID mice. We found that these primary ccRCC cells are affected in the same way as tumor cell lines and in the orthotopic model tumor growth was significantly reduced by the treatment. This study on patient-derived ccRCC tumor cells represents a model closer to actual patient ccRCC tumors and shows that knockdown of ASncmtRNAs poses a potential treatment option for these patients.

7.
Plants (Basel) ; 12(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36771743

RESUMO

The present study analyzed Medicago sativa L. crops irrigated by TiO2 in the anatase phase and TiO2 doped with Ag, Fe, and Cu ions at 0.1%w synthesized using the sol-gel method (SG) and the sol-gel method coupled with microwave (Mw-SG). The materials were added to the irrigation water at different concentrations (50, 100, and 500 ppm). Stress induction by nanomaterials was observed by measuring stem morphology, chlorophyll index, total phenols and flavonoids, and antioxidant activity through the DPPH (2,2-diphenyl-1-picrylhydrazy) radical inhibition assay. The nanomaterial treatments caused statistically significant reductions in parameters such as stem length, leaf size, and chlorophyll index and increases in total phenol content and DPPH inhibition percentage. However, the observed effects did not show clear evidence regarding the type of nanomaterial used, its synthesis methodology, or a concentration-dependent response. By generally grouping the results obtained to the type of dopant used and the synthesis method, the relationship between them was determined employing a two-way ANOVA. It was observed that the dopant factors, synthesis, and interaction were relevant for most treatments. Additionally, the addition of microwaves in the synthesis method resulted in the largest number of treatments with a significant increase in the total content of phenols and the % inhibition compared to the traditional sol-gel synthesis. In contrast, parameters such as stem size and chlorophyll index were affected under different treatments from both synthesis methods.

8.
Nanomaterials (Basel) ; 13(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37947670

RESUMO

Nanomaterials such as titanium dioxide and magnetite are increasingly used in several fields, such as water remediation and agriculture. However, this has raised environmental concerns due to potential exposure to organisms like humans. Nanomaterials can cause adverse interactions depending on physicochemical characteristics, like size, morphology, and composition, when interacting with living beings. To ensure safe use and prevent the risk of exposure to nanomaterials, their biocompatibility must be assessed. In vitro cell cultures are beneficial for assessing nanomaterial-cell interactions due to their easy handling. The present study evaluated the biocompatibility of TiO2, Fe3O4, and TiO2/Fe3O4 nanomaterials thermally treated at 350 °C and 450 °C in erythrocytes and HepG2 cells. According to the hemolysis experiments, non-thermally treated NMs are toxic (>5% hemolysis), but their thermally treated counterparts do not present toxicity (<2%). This behavior indicates that the toxicity derives from some precursor (solvent or surfactant) used in the synthesis of the nanomaterials. All the thermally treated nanomaterials did not show hemolytic activity under different conditions, such as low-light exposure or the absence of blood plasma proteins. In contrast, non-thermally treated nanomaterials showed a high hemolytic behavior, which was reduced after the purification (washing and thermal treatment) of nanomaterials, indicating the presence of surfactant residue used during synthesis. An MTS cell viability assay shows that calcined nanomaterials do not reduce cell viability (>11%) during 24 h of exposure. On the other hand, a lactate dehydrogenase leakage assay resulted in a higher variability, indicating that several nanomaterials did not cause an increase in cell death as compared to the control. However, a holotomographic microscopy analysis reveals a high accumulation of nanomaterials in the cell structure at a low concentration (10 µg mL-1), altering cell morphology, which could lead to cell membrane damage and cell viability reduction.

9.
Pilot Feasibility Stud ; 9(1): 30, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36855214

RESUMO

BACKGROUND: Interventions to promote physical activity among women breast cancer survivors (BCS) in low- to middle-income countries are limited. We assessed the acceptability and preliminary effectiveness of a theory-driven, group-based dance intervention for BCS delivered in Bogotá, Colombia. METHODS: We conducted a quasi-experimental study employing a mixed-methods approach to assess the 8-week, 3 times/week group dance intervention. The effect of the intervention on participants' physical activity levels (measured by accelerometry), motivation to engage in physical activity, and quality of life were evaluated using generalized estimating equation analysis. The qualitative method included semi-structured interviews thematically analyzed to evaluate program acceptability. RESULTS: Sixty-four BCS were allocated to the intervention (n = 31) or the control groups (n = 33). In the intervention arm, 84% attended ≥ 60% of sessions. We found increases on average minutes of moderate-to-vigorous physical activity per day (intervention: +8.99 vs control: -3.7 min), and in ratings of motivation (intervention change score = 0.45, vs. control change score= -0.05). BCS reported improvements in perceived behavioral capabilities to be active, captured through the interviews. CONCLUSIONS: The high attendance, behavioral changes, and successful delivery indicate the potential effectiveness, feasibility, and scalability of the intervention for BCS in Colombia. TRIAL REGISTRATION: ClinicalTrial.gov NCT05252780, registered on Dec 7th, 2021-retrospectively registered unique protocol ID: P20CA217199-9492018.

10.
J Nanosci Nanotechnol ; 12(3): 2750-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22755118

RESUMO

We have studied polystyrene (PS)+Au particles nanohybrids. Approximately spherical gold nanoparticles with the average diameter of 15 nm were obtained by laser ablation in a liquid environment. Thus any chemical residue on the particles was eliminated. Focused ion beam (FIB) milling plus scanning electron microscopy (SEM) observation show that Au particles are fairly well dispersed inside the polymer matrix, better than when PS is simply dissolved in a nanoparticle solution. The Au particles concentration as low as 0.15 wt% results in dramatic changes in tribological properties, namely dynamic friction and pin-on-disk wear. Both wear and dynamic friction results are explained in terms of high brittleness of PS, abrasion of Au particles against a ceramic indenter, and also effects of density of filler particles in the matrix on tribological properties. Effects of varying normal load on friction are small.

11.
J Neurosurg Case Lessons ; 4(6)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-36088566

RESUMO

BACKGROUND: Tentorial dural arteriovenous fistulas (DAVFs) with perimedullary venous drainage causing cervical myelopathy are very uncommon conditions with an extremely aggressive behavior. When the characteristic radiological clues are missing, the unspecific clinical picture may cause delay and make the diagnosis challenging. OBSERVATIONS: Here the authors report a case of a 58-year-old man who developed progressive spastic tetraparesis and dyspnea with an extensive mild enhancing cervical cord lesion initially oriented as a neurosyphilis-associated transverse myelitis. Acute worsening after steroid administration redirected the diagnosis, and a tentorial Cognard type V DAVF was elicited. The microsurgical disconnection process is described, and previously documented cases in the literature are reviewed. LESSONS: If a DAVF is highly suspected, it is important to consider the possibility of its intracranial origin, and spinal as well as cerebral arteriography must be performed.

12.
Nanomaterials (Basel) ; 12(11)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35683797

RESUMO

The problem of water pollution by persistent substances and microorganisms requires solutions that materials such as silver-modified titanium dioxide can provide due to their excellent photocatalytic and antimicrobial properties. However, the synthesis methods conventionally used to obtain these materials involve toxic chemical reagents such as sodium borohydride (NaBH4). The search for alternative synthesis methods that use environmentally friendly substances, such as the biosynthesis method, was evaluated. Silver-titanium dioxide (Ag-TiO2) was synthesized by a Eucalyptus globulus L. extract as a reductive agent through sol-gel and microwave-assisted sol-gel processes. Four different solvents were tested to extract secondary metabolites to determine their roles in reducing silver nanoparticles. Titanium dioxide nanoparticles with sizes from 11 to 14 nm were obtained in the anatase phase, and no narrowing of the bandgap was observed (3.1-3.2 eV) for the Ag-TiO2 materials compared with the pure TiO2. Interestingly, the bacterial inhibition values were close to 100%, suggesting an effective antimicrobial mechanism related to the properties of silver. Finally, by the physicochemical characterization of the materials and their antimicrobial properties, it was possible to obtain a suitable biosynthesized Ag-TiO2 material as a green option for water disinfection that may be compared to the conventional methods.

13.
Brain Sci ; 11(1)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33450843

RESUMO

(1) Background: The impact of the health crisis caused by coronavirus disease 2019 (COVID-19) has provoked collateral effects in the attention to pathologies with time-dependent treatments such as strokes. We compare the healthcare activity of two stroke units in the same periods of 2019 and 2020, with an emphasis on what happened during the state of alarm (SA). (2) Materials and methods. Hospitals in the region implemented contingency plans to contain the pandemic; in this planning, the stroke units were not limited in their operational capacity. The SA was declared on 15 March and remained in place for 10 weeks. For the analysis, the data were grouped by consecutive calendar weeks. (3) Results. When the SA was declared the number of calls to the emergency telephone went from 1225 to 3908 calls per week (318% increase). However, the activation of the stroke code went from 6.6 to 5.0 (p = 0.04) and the activity in both stroke units decreased. The largest drop in hospitalizations was for transient ischemic attacks (TIAs) with 35.7% less, 28 vs. 18, (p = 0.05). Reperfusion therapies fell by 37.5%; Poisson regression model 0.64; (95% confidence interval (CI), 0.43-0.95). The overall activity of the telestroke suffered a reduction of 28.9%. We also observed an increase in hospital mortality. (4) Conclusion. The excessive duration of the pandemic precludes any hope of resolving this public health crisis in the short or medium term. Further studies should be conducted to better understand the multifactorial nature of this dramatic decline in stroke admissions and its negative impact.

14.
Med Chem ; 16(7): 984-990, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31448714

RESUMO

BACKGROUND: One of the possible ways of improving the activity and selectivity profile of anticancer agents is to design drug carrier systems employing nanomolecules. Calix[4]arene derivatives and chlorambucil and ibuprofen are important compounds that exhibit interesting anticancer properties. OBJECTIVE: The objective of this article is the synthesis of new calix[4]arene-derivative conjugates of chlorambucil or ibuprofen with potential anticancer activity. METHODS: Cytotoxicity assays were determined using the protein-binding dye sulforhodamine B (SRB) in microculture to measure cell growth as described [19, 20]. Conjugates of chlorambucil and resorcinarene-dendrimers were prepared in 2% DMSO and added into the culture medium immediately before use. Control cells were treated with 2% DMSO. RESULTS: Thus, calix[4]arene-derivative conjugates of chlorambucil or ibuprofen showed good stability of the chemical link between drug and spacer. Evaluation of the cytotoxicity of the calix[4]arene chlorambucil or ibuprofen conjugates employing a sulforhodamine B (SRB) assay in K-562 (human chronic myelogenous leukemia cells) and U-251 (human glioblastoma cells) demonstrated that the conjugate was more potent as an antiproliferative agent than free chlorambucil and ibuprofen. The conjugates did not show any activity against the COS-7 African green monkey kidney fibroblast cell line. CONCLUSION: In the paper, we report the synthesis and spectroscopic analyses of new calix[4]arene derivative conjugates of chlorambucil or ibuprofen. Cytotoxicity assays revealed that at 10 µM, the conjugates were very active against K-562 (human chronic myelogenous leukemia cells) and U- 251 (human glioblastoma cells) cancer cells' proliferation. In order to explain the molecular mechanisms involved in the anticancer activity of calix[4]arene chlorambucil or ibuprofen conjugates, our research will be continued.


Assuntos
Antineoplásicos/farmacologia , Calixarenos/farmacologia , Clorambucila/farmacologia , Ibuprofeno/farmacologia , Fenóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Calixarenos/química , Proliferação de Células/efeitos dos fármacos , Clorambucila/síntese química , Clorambucila/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ibuprofeno/síntese química , Ibuprofeno/química , Estrutura Molecular , Fenóis/química , Células Tumorais Cultivadas
15.
J Cancer ; 11(7): 1780-1791, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32194789

RESUMO

Knockdown of the antisense noncoding mitochondrial RNAs (ASncmtRNAs) induces apoptotic death of several human tumor cell lines, but not normal cells, supporting a selective therapy against different types of cancer. In this work, we evaluated the effects of knockdown of ASncmtRNAs on bladder cancer (BCa). We transfected the BCa cell lines UMUC-3, RT4 and T24 with the specific antisense oligonucleotide Andes-1537S, targeted to the human ASncmtRNAs. Knockdown induced a strong inhibition of cell proliferation and increase in cell death in all three cell lines. As observed in UMUC-3 cells, the treatment triggered apoptosis, evidenced by loss of mitochondrial membrane potential and Annexin V staining, along with activation of procaspase-3 and downregulation of the anti-apoptotic factors survivin and Bcl-xL. Treatment also inhibited cell invasion and spheroid formation together with inhibition of N-cadherin and MMP 11. In vivo treatment of subcutaneous xenograft UMUC-3 tumors in NOD/SCID mice with Andes-1537S induced inhibition of tumor growth as compared to saline control. Similarly, treatment of a high-grade bladder cancer PDX with Andes-1537S resulted in a strong inhibition of tumor growth. Our results suggest that ASncmtRNAs could be potent targets for bladder cancer as adjuvant therapy.

16.
JACC Cardiovasc Interv ; 12(9): 873-882, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-31072509

RESUMO

OBJECTIVES: The aim of the HISPANIAS (HyperperfusIon Syndrome Post-carotid ANgIoplasty And Stenting) study was to define CHS rates and develop a clinical predictive model for cerebral hyperperfusion syndrome (CHS) after carotid artery stenting (CAS). BACKGROUND: CHS is a severe complication following CAS. The presence of clinical manifestations is estimated on the basis of retrospective reviews and is still uncertain. METHODS: The HISPANIAS study was a national prospective multicenter study with 14 recruiting hospitals. CHS was classified as mild (headache only) and moderate-severe (seizure, impaired level of consciousness, or development of focal neurological signs). RESULTS: A total of 757 CAS procedures were performed. CHS occurred in 22 (2.9%) patients, in which 16 (2.1%) had moderate-severe CHS and 6 (0.8%) had mild CHS (only headache). The rate of hemorrhages was 0.7% and was associated with high mortality (20%). Pre-operative predictors of moderate-severe CHS in multivariate analysis were female sex (odds ratio [OR]: 3.24; 95% confidence interval [CI]: 1.11 to 9.47; p = 0.03), older patients (OR: 1.09; 95% CI: 1.01 to 1.17; p = 0.02), left carotid artery treated (OR: 4.13; 95% CI: 1.11 to 15.40; p = 0.03), and chronic renal failure (OR: 6.29; 95% CI: 1.75 to 22.57; p = 0.005). The area under the curve of this clinical and radiological model was 0.86 (95% CI: 0.81 to 0.92; p = 0.001). CONCLUSIONS: The rate of CHS in the HISPANIAS study was 2.9%, with moderate-severe CHS of 2.1%. CHS was independently associated with female sex, older age, history of chronic kidney disease, and a treated left carotid artery. Although further investigations are needed, the authors propose a model to identify high-risk patients and develop strategies to decrease CHS morbidity and mortality in the future.


Assuntos
Estenose das Carótidas/terapia , Circulação Cerebrovascular , Transtornos Cerebrovasculares/epidemiologia , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Hemodinâmica , Stents , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/mortalidade , Estenose das Carótidas/fisiopatologia , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/mortalidade , Transtornos Cerebrovasculares/fisiopatologia , Transtornos da Consciência/epidemiologia , Transtornos da Consciência/fisiopatologia , Procedimentos Endovasculares/mortalidade , Feminino , Cefaleia/epidemiologia , Cefaleia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal Crônica/epidemiologia , Medição de Risco , Fatores de Risco , Convulsões/epidemiologia , Convulsões/fisiopatologia , Índice de Gravidade de Doença , Fatores Sexuais , Espanha/epidemiologia , Fatores de Tempo , Resultado do Tratamento
17.
Nanomaterials (Basel) ; 8(7)2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30036967

RESUMO

Biosensor technology has great potential for the detection of cancer through tumor-associated molecular biomarkers. In this work, we describe the immobilization of the recombinant humanized anti-HER2 monoclonal antibody (trastuzumab) on a silver nanostructured plate made by pulsed laser deposition (PLD), over a thin film of Au(111). Immobilization was performed via 4-mercapto benzoic acid self-assembled monolayers (4-MBA SAMs) that were activated with coupling reagents. A combination of immunofluorescence images and z-stack analysis by confocal laser scanning microscopy (CLSM) allowed us to detect HER2 presence and distribution in the cell membranes. Four different HER2-expressing breast cancer cell lines (SKBR3 +++, MCF-7 +/-, T47D +/-, MDA-MB-231 -) were incubated during 24 h on functionalized silver nanostructured plates (FSNP) and also on Au(111) thin films. The cells were fixed by means of an ethanol dehydration train, then characterized by atomic force microscopy (AFM) and surface-enhanced Raman scattering (SERS). SERS results showed the same tendency as CLSM findings (SKBR3 > MCF-7 > T47D > MDA-MB-231), especially when the Raman peak associated with phenylalanine amino acid (1002 cm-1) was monitored. Given the high selectivity and high sensitivity of SERS with a functionalized silver nanostructured plate (FSNP), we propose this method for identifying the presence of HER2 and consequently, of breast cancer cells.

18.
Accid Anal Prev ; 94: 107-18, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27269999

RESUMO

Over the years many prevention management practices have been implemented to prevent and mitigate accidents at the construction site. However, there is little evidence of the effectiveness of individual or combined practices used by companies to manage occupational health and safety issues. The authors selected a sample of 1180 construction firms and 221 individual practices applied in these companies to analyze their effectiveness reducing injury rates over a period of four years in Chile. Different methods were used to study this massive database including: visual analyses of graphical information, statistical analyses and classification techniques. Results showed that practices related to safety incentives and rewards are the most effective from the accident rate viewpoint, even though they are seldom used by companies; on the other hand, practices related to accidents and incidents investigation had a slight negative impact on the accident rate because they are frequently used as a reactive measure. In general, the higher the percentage of prevention practices implemented in a strategy, the lower the accident rate. However, the analysis of the combined effect of prevention practices indicated that the choice of the right combination of practices was more important than just the number of practices implemented.


Assuntos
Acidentes de Trabalho/prevenção & controle , Indústria da Construção/normas , Traumatismos Ocupacionais/prevenção & controle , Gestão da Segurança/métodos , Acidentes de Trabalho/estatística & dados numéricos , Chile/epidemiologia , Indústria da Construção/estatística & dados numéricos , Bases de Dados Factuais , Humanos , Saúde Ocupacional/normas , Saúde Ocupacional/estatística & dados numéricos , Traumatismos Ocupacionais/epidemiologia , Gestão da Segurança/normas , Gestão da Segurança/estatística & dados numéricos
19.
Rev. chil. cardiol ; 40(3): 184-195, dic. 2021. tab, graf, ilus
Artigo em Espanhol | LILACS | ID: biblio-1388104

RESUMO

INTRODUCCIÓN: Actualmente, hay nuevas herramientas de software disponibles para medir la sincronía de la contracción intraventricular izquierda mediante SPECT de perfusión miocárdica. Esta técnica permite identificar anomalías de la conducción, apoyar la terapia de resincronización en insuficiencia cardíaca refractaria e incluso la detección precoz de isquemia. OBJETIVO: Conocer la correlación de la sincronía de contracción con otros parámetros de disfunción sisto-diastólica ventricular izquierda. MÉTODO: Estudiamos 135 pacientes remitidos para pesquisa o evaluación de enfermedad coronaria conocida mediante SPECT gatillado. La evaluación de la interpretación inicial con programas QPS/QGS® visual y cuantitativo se efectuó a 50 casos con defectos de perfusión transitoria de diversos tamaños (isquemia), 25 de tipo fijo o mixto (infarto) y 60 sin ellos (normal). Los volúmenes telesistólicos oscilaron entre 26 y 458 mL. Se excluyeron casos con arritmias, anomalías de conducción y artefactos (actividad o movimiento extracardiaco). Los SPECT se procesaron retrospectivamente utilizando el programa Emory Synctool®. Del histograma de sincronía de la contracción, el ancho de banda (BW) y la desviación estándar (SD) se correlacionaron con la fracción de eyección (FEVI), volúmenes y excentricidades sistólico / diastólico, masa ventricular izquierda, tasa máxima de llenado (PFR) y tiempo al máximo de llenado (TPFR). RESULTADOS: Los BW y SD del histograma de fase de contracción fueron mayores en el grupo con defectos fijos y mixtos en comparación con los con perfusión normal. Las correlaciones en reposo y post estrés (Spearman) entre SD y BW con FEVI, volúmenes, excentricidad y masa fueron significativas (p <0,0002) salvo TPFR que no fue significativa. CONCLUSIÓN: La sincronía de contracción intraventricular sistólica izquierda medida con SPECT se correlaciona excelentemente con los parámetros funcionales sistólicos y diastólicos, así como con masa y excentricidad en diversas condiciones y tamaños cardíacos.


INTRODUCTION: New software tools are available to measure left intraventricular contraction synchrony by myocardial perfusion SPECT. This technique allows identification of conduction abnormalities, support resynchronization therapy in refractory heart failure and even allows early detection of myocardial ischemia. OBJECTIVE: To determine the correlation of systolic synchrony with other parameters of left ventricular systolic-diastolic dysfunction. METHODS: We studied 135 patients referred for screening or known coronary artery disease evaluation by triggered SPECT. Evaluation of the initial interpretation with visual and quantitative QPS/QGS® programs was performed in 50 patients with transient perfusion defects of various sizes (ischemia), 25 of fixed or mixed type (infarction) and 60 without abnormalities. Telesystolic volumes ranged from 26 to 458 mL. Cases with arrhythmias, conduction abnormalities and artifacts (extracardiac activity or motion) were excluded. SPECT scans were retrospectively processed using the Emory Synctool® software. Histograms of systolic contraction synchrony bandwidth (BW) and standard deviation (SD) were correlated with ejection fraction (LVEF), systolic/diastolic volumes and eccentricities, left ventricular mass, peak filling rate (PFR) and time to maximum filling (TPFR). RESULTS: BW and SD of the contraction pase histogram were higher in the fixed and mixed defect group compared to studies showing normal perfusion. Spearman correlations at rest and poststress between SD and BW with LVEF, volumes, eccentricity and mass were all significant (p<0.0002) except for TPFR. CONCLUSION: Left systolic intraventricular contraction synchrony measured with SPECT presents an excellent correlation with systolic and diastolic functional parameters, as well as with mass and eccentricity in various cardiac conditions and ventricular dimensions.


Assuntos
Humanos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Imagem de Perfusão do Miocárdio , Cardiopatias/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Software , Imagem do Acúmulo Cardíaco de Comporta , Estudos Retrospectivos , Disfunção Ventricular Esquerda
20.
Nutr Hosp ; 32(5): 2228-34, 2015 Nov 01.
Artigo em Espanhol | MEDLINE | ID: mdl-26545682

RESUMO

During the past five decades there has been an increased in the prevalence of obesity and over weight, also in physical inactivity and /or low cardiorespiratory fitness within the population in school age from diverse regions of the planet, including Bogota-Colombia. The general objective of this study was to compare the physical condition and the levels of physical activity from students who belonged to two curriculum programs of the Public Schools Network from Bogota, one of which includes two sessions per week, each session of 90 minutes of physical activity. We developed a research of unlike cross-sectional groups. There were 178 children evaluated from the regular curriculum and 170 kids belonging to the program 40 x 40. The physical condition was evaluated applying the protocol of high priority from the ALPHA -Fitness test Battery. The weight, height, body mass index, the waist circumference, the standing long jump, the handgrip in both hands and the motor fitness 20 meter shuttle run test were developed under standardized conditions. The Global School Health Survey (GSHS) was used to evaluate the levels of AF. No significant statistical differences were founded between P-40x40 and the regular curriculum regarding: weight, height, the body mass index, the waist circumference, the handgrip in both hands and the explosive strength in lower limbs. Nevertheless the cardiorespiratory fitness was significantly lower within de P-40x40. In conclusion the participation in the curricular program 40 x 40 was not associated with better levels of physical condition.


Durante las últimas cinco décadas se han incrementado las prevalencias de sobrepeso/obesidad, inactividad física y/o baja capacidad cardiorrespiratoria en la población en edad escolar de diversas regiones del planeta, incluida la de Bogotá, Colombia. El objetivo general del estudio fue comparar la condición física y los niveles de actividad física de los estudiantes pertenecientes a dos programas curriculares de la red de colegios públicos de Bogotá, uno de los cuales incluye dos sesiones de actividad física a la semana de 90 minutos cada una. Se llevó a cabo un estudio de diferencia de grupos de corte transversal. Se evaluaron 178 niños del currículo regular y 170 pertenecientes al programa 40 x 40. La condición física se evaluó aplicando el protocolo de alta prioridad de la batería de test ALPHA -Fitness. Las medidas del peso, la talla, el perímetro de cintura, el salto de longitud, la fuerza prensil en ambas manos y la prueba de 20 metros ida y vuelta se realizaron en condiciones estandarizadas. Para evaluar los niveles de AF se utilizó la encuesta mundial de salud a escolares (GSHS). No se encontraron diferencias estadísticamente significativas entre el P-40x40 y el currículo regular en cuanto al peso, la talla, el índice de masa corporal, el perímetro de la cintura, la fuerza de prensión manual y la fuerza explosiva de los miembros inferiores. Sin embargo, la capacidad cardiorrespiratoria fue significativamente menor dentro del P-40x40. En conclusión, la participación en el programa curricular 40 x 40 no estuvo asociada a mejores niveles de condición física.


Assuntos
Exercício Físico , Adolescente , Colômbia , Estudos Transversais , Currículo , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Aptidão Física/fisiologia , Instituições Acadêmicas , Estudantes
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