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Acta Physiologica Sinica ; (6): 181-196, 2021.
Article in English | WPRIM | ID: wpr-878247


Organoids are self-organized cellular clusters in three-dimensional culture, which can be derived from a single stem cell, progenitor or cell clusters of different lineages resembling in vivo tissue architecture of an organ. In the recent years, organoids technology has contributed to the revolutionary changes in stem cell and cancer fields. In this review, we have briefly overviewed the emerging landscape of prostate organoid technology (POT) in prostate research. In addition, we have also summarized the potential application of POT in the understanding of prostate stem cell and cancer biology and the discovery of novel therapeutic strategies for prostate cancer. Lastly, we have critically discussed key challenges that lie in the current state of POT and provided a future perspective on the second-generation of POT, which should better recapitulate cellular behaviors and drug responses of prostate cancer patients.

Gold , Humans , Male , Neoplasms , Organoids , Prostate , Stem Cells , Technology
Chinese Journal of Biotechnology ; (12): 3323-3333, 2021.
Article in Chinese | WPRIM | ID: wpr-921428


Vibrio splendidus is an opportunistic pathogen in aquaculture. It can infect a variety of aquaculture animals and has caused huge losses to the aquaculture industry. In this study, a novel and efficient method for detecting V. splendidus was developed by combining the exonuclease Ⅲ amplification strategy with a nucleic acid test strip developed based on gold nanoparticles-labeled DNA probe. The results could be directly visualized by naked eyes, and this system overcame the difficulty in preparation of the monoclonal antibody used in conventional immunostrip. Upon optimization of experimental conditions, the detection limit of the strip was 5 ng/mL for the synthetic oligonucleotide DNA fragment and 10 ng/mL for the actual genomic DNA sample of V. splendidus. This test strip was more sensitive compared with the PCR method and was specific for the detection of V. splendidus. The rapid preparation of nucleic acid strip and the efficient detection of V. splendidus open a new way for the prevention and control of aquatic diseases.

Animals , DNA Probes , Gold , Metal Nanoparticles , Vibrio/genetics
Braz. J. Pharm. Sci. (Online) ; 57: e19040, 2021. tab
Article in English | LILACS | ID: biblio-1350239


Diabetes and its complications represent a major cause of morbidity and mortality in diabetes patients. This review is aimed to find the potential of gold nanoparticles (AuNPs) to act as therapeutic agents for diabetes and its complications. Here, we outline the literature related to the self-therapeutic effects of AuNPs. The first goal of this review is to highlight and summarize some of the existing studies (10 years ago) in terms of several parameters such as the size of AuNPs, dose, administration route, experimental model, experimental analysis, and findings. The second goal is to describe the self-therapeutic effects of AuNPs against the pathogenesis determinants of diabetic complications. AuNPs have been found to have inhibitory effects on transforming growth factor-ß, antiglycation, antiangiogenic, anti-hyperglycemic, anti-inflammatory, and antioxidant effects. AuNPs treatment effectively disrupts multiple pathogenesis determinants in an animal model of diabetes and diabetic complications. The present review provides insight into the potential applications of AuNPs, which may help reduce the incidence of diabetes and its complications

Therapeutic Uses , Diabetes Complications/drug therapy , Nanoparticles/metabolism , Gold/classification , Organization and Administration , Patients , Models, Animal , Models, Theoretical , Antioxidants/pharmacology
Int. braz. j. urol ; 46(3): 314-321, May-June 2020. graf
Article in English | LILACS | ID: biblio-1090624


ABSTRACT Vesicoureteral reflux, the retrograde flow of urine from the bladder into the upper urinary tract, is one of the most common urologic diagnoses in the pediatric population. Once detected, therapeutic options for urinary reflux are diverse, ranging from observation with or without continuous low-dose prophylactic antibiotics to a variety of operative interventions. While a standardized algorithm is lacking, it is generally accepted that management be tailored to individual patients based on various factors including age, likelihood of spontaneous resolution, risk of subsequent urinary tract infections with renal parenchymal injury, and parental preference. Anti-reflux surgery may be necessary in children with persistent reflux, renal scarring or recurrent pyelonephritis after optimization of bladder and bowel habits. Open, laparoscopic/robot-assisted and endoscopic approaches are all successful in correcting reflux and have been shown to reduce the incidence of febrile urinary tract infections.

Humans , Child , Vesico-Ureteral Reflux/surgery , Replantation , Urinary Tract Infections , Gold
Braz. j. otorhinolaryngol. (Impr.) ; 86(3): 294-299, May-June 2020. tab, graf
Article in English | LILACS | ID: biblio-1132593


Abstract Introduction: South Africa has a high prevalence of co-existing tuberculosis and HIV. As ototoxicity linked to the treatments for these conditions occurs with concomitant exposure to other ear toxins such as hazardous noise exposure, it is important to investigate the combination impact of these toxins. Limited published evidence exists on the co-occurrence of these conditions within this population. Objectives: The objective of this study was to compare the hearing function of gold miners with (treatment group) and without (non-treatment group) the history of tuberculosis treatment, in order to determine which group had increased risk of noise induced hearing loss. Furthermore, possible influence of age and HIV in these two groups was examined. Methods: A retrospective record review of 102 miners' audiological records, divided into two groups, was conducted, with data analyzed both qualitatively and quantitatively. Results: Findings suggest that gold miners with a history of tuberculosis treatment have worse hearing thresholds in the high frequencies when compared to those without this history; with evidence of a noise induced hearing loss notch at 6000 Hz in both groups. Pearson's correlations showed values between 0 and 0.3 (0 and −0.3) which are indicative of a weak positive (negative) correlation between HIV and hearing loss, as well as between hearing loss and age in this population. Conclusions: Current findings highlight the importance of strategic hearing conservation programs, including ototoxicity monitoring, and the possible use of oto-protective/chemo-protective agents in this population.

Resumo Introdução: A África do Sul apresenta uma alta prevalência de coinfecção de tuberculose e HIV. Como a ototoxicidade associada aos tratamentos para essas condições é observada na exposição concomitante a outros agentes ototóxicos, como a exposição a ruídos perigosos, é importante investigar o impacto da combinação desses agentes. São poucas as evidências publicadas sobre a co-ocorrência dessas condições nessa população. Objetivo: Comparar a função auditiva de garimpeiros com (grupo tratamento) e sem (grupo sem tratamento) história de tratamento de tuberculose, a fim de determinar que grupo apresentava maior risco de perda auditiva induzida por ruído. Além disso, avaliou-se a possível influência da idade e do HIV nesses dois grupos. Método: Os registros audiológicos de 102 garimpeiros, divididos em dois grupos, foram revisados de forma retrospectiva; os dados foram qualitativa e quantitativamente analisados. Resultados: Os achados indicam os garimpeiros com histórico de tratamento de tuberculose apresentam piores limiares auditivos nas altas frequências quando comparados àqueles sem esse histórico; em ambos os grupos, observou-se perda auditiva induzida por ruído com entalhe audiométrico a 6.000 Hz. As correlações de Pearson mostraram valores entre 0 e 0,3 (0 e -0,3), que são indicativos de uma fraca correlação positiva (negativa) entre o HIV e a perda auditiva, bem como entre a perda auditiva e a idade nessa população. Conclusões: Os resultados atuais destacam a importância de programas estratégicos de conservação auditiva, inclusive monitoramento de ototoxicidade, e o possível uso de agentes oto-/quimioprotetores nessa população.

Humans , Adolescent , Adult , Middle Aged , Young Adult , Tuberculosis/epidemiology , Occupational Exposure/adverse effects , Gold , Hearing Loss, Noise-Induced/epidemiology , Mining , Noise, Occupational/adverse effects , Occupational Diseases/epidemiology , South Africa/epidemiology , Prevalence , Cross-Sectional Studies , Retrospective Studies , Risk Factors , Hearing Loss, Noise-Induced/diagnosis , Hearing Tests
Mem. Inst. Oswaldo Cruz ; 115: e200043, 2020. tab, graf
Article in English | SES-SP, LILACS, SES-SP | ID: biblio-1135250


BACKGROUND The number of malaria cases in Roraima nearly tripled from 2016 to 2018. The capital, Boa Vista, considered a low-risk area for malaria transmission, reported an increasing number of autochthonous and imported cases. OBJECTIVES This study describes a spatial analysis on malaria cases in an urban region of Boa Vista, which sought to identify the autochthonous and imported cases and associated them with Anopheles habitats and the potential risk of local transmission. METHODS In a cross-sectional study at the Polyclinic Cosme e Silva, 520 individuals were interviewed and diagnosed with malaria by microscopic examination. Using a global positional system, the locations of malaria cases by type and origin and the breeding sites of anopheline vectors were mapped and the risk of malaria transmission was evaluated by spatial point pattern analysis. FINDINGS Malaria was detected in 57.5% of the individuals and there was a disproportionate number of imported cases (90.6%) linked to Brazilian coming from gold mining sites in Venezuela and Guyana. MAIN CONCLUSIONS The increase in imported malaria cases circulating in the west region of Boa Vista, where there are positive breeding sites for the main vectors, may represent a potential condition for increased autochthonous malaria transmission in this space.

Humans , Animals , Male , Female , Adult , Plasmodium/isolation & purification , Travel , Miners/statistics & numerical data , Mosquito Vectors/parasitology , Malaria/diagnosis , Malaria/transmission , Anopheles/parasitology , Plasmodium/classification , Urban Population , Venezuela , Brazil/epidemiology , Cross-Sectional Studies , Geographic Information Systems , Spatial Analysis , Gold , Guyana , Malaria/parasitology , Malaria/epidemiology , Anopheles/classification , Middle Aged
Article in Chinese | WPRIM | ID: wpr-878790


A highly specific electrochemical biosensor based on T-Hg~(2+)-T structure for fast screening trace Hg~(2+) in complex animal drug matrix was constructed by cyclic voltammetry(CV) and differential pulse voltammetry(DPV). In the presence of Hg~(2+), it can be specifically binded to the T base of DNA sequence on the surface of modified gold electrode, which changes the conformation of DNA molecule and the electrochemical signal. The concentration ratio of EDC/NHS, the concentration ratio of FC-DNA and the reaction time of the biosensor were optimized by the index of sensitivity and reproducibility in CV. The results showed that the stability of the biosensor was good within 3 days(RSD≤1.3%), the difference between batches was low(RSD=4.7%), and the specificity of the biosensor was high in the presence of interfering ions(As~(3+), Cd~(2+), Cu~(2+), Pb~(2+), Zn~(2+) and Fe~(3+)). DPV results showed that the peak current signal value has a linear relationship with the lgC_((Hg)) over a concentration range from 0.1 nmol·L~(-1) to 1.0 μmol·L~(-1) with a detection limit of 0.066 nmol·L~(-1). Finally, the recovery rate tested in the matrix of animal medicine was satisfactory as 99.17%-101.3%, which can meet the needs of the determination of trace Hg~(2+) in the matrix of Bombyx Batryticatus, and provide a new idea for the rapid screening of trace heavy metals in the matrix of other types of complex traditional Chinese medicine.

Animals , Biosensing Techniques , DNA/genetics , Electrochemical Techniques , Gold , Mercury , Reproducibility of Results
Biol. Res ; 53: 26, 2020. graf
Article in English | LILACS | ID: biblio-1124211


BACKGROUND: There Is an emerging field to put Into practice new strategies for developing molecules with antimicrobial properties. In this line, several metals and metalloids are currently being used for these purposes, although their cellular effect(s) or target(s) in a particular organism are still unknown. Here we aimed to investigate and analyze Au3+ toxicity through a combination of biochemical and molecular approaches. RESULTS: We found that Au3+ triggers a major oxidative unbalance in Escherichia coli, characterized by decreased intracellular thiol levels, increased superoxide concentration, as well as by an augmented production of the antioxidant enzymes superoxide dismutase and catalase. Because ROS production is, in some cases, associated with metal reduction and the concomitant generation of gold-containing nanostructures (AuNS), this possibility was evaluated in vivo and in vitro. CONCLUSIONS: Au3+ is toxic for E. coli because it triggers an unbalance of the bacterium's oxidative status. This was demonstrated by using oxidative stress dyes and antioxidant chemicals as well as gene reporters, RSH concentrations and AuNS generation.

Oxidation-Reduction/drug effects , Oxidative Stress/drug effects , Escherichia coli/drug effects , Metal Nanoparticles/toxicity , Gold/toxicity
Article in Chinese | WPRIM | ID: wpr-775921


OBJECTIVE@#To observe the clinical therapeutic effects of auricular gold-needle therapy on chronic fatigue syndrome of deficiency constitution and explore its potential mechanism.@*METHODS@#A total of 120 patients were randomized into an auricular gold-needle therapy group, an auricular point pressure therapy group and a Chinese herb group, 40 cases in each one. Additionally, a health control group (40 cases) was set up, without any intervention. In the auricular gold-needle therapy group, the gold needle was used to stimulate the auricular points on one side and the cowherb seed pressure therapy on the other side. In the auricular point pressure therapy group, the cowherb seed pressure therapy was adopted only on one side. The auricular points were shen (CO), xin (CO), fei (CO), pizhixia (AT), etc. in the two groups. The auricular points on both sides were used alternatively. The treatment was given once a week, 4 treatments as one course and the consecutive 3 courses of treatment were required. In the Chinese herb group, was prescribed for oral administration, 6 g, twice a day, the medication for 1 month was as one session and the consecutive 3 sessions of medication were required. Before and after treatment, separately, the clinical symptom score, the levels of the serum immunoglobulins, i.e. IgA, IgG and IgM were observed in the patients of the three groups. The therapeutic effects were evaluated in the three groups.@*RESULTS@#The total effective rate was 90.0% (36/40) in the auricular gold-needle therapy group, better than 80.0% (32/40) in the auricular point pressure therapy group and 82.5% (33/40) in the Chinese herb group (both <0.05). Before treatment, the clinical symptom scores of the patients in the three groups were obviously higher than the health control group (all <0.001). After treatment, the symptom scores were all reduced as compared the scores before treatment in the three groups (all <0.001) and the symptom scores in the auricular gold-needle therapy group were better than the auricular point pressure therapy group and the Chinese herb group (both <0.01). Before treatment, the levels of serum IgA, IgG and IgM of the patients in the three groups were lower than the health control group (all <0.001). The levels were all improved after treatment in the three groups (all <0.01), and the levels in the auricular gold-needle therapy group was better than the auricular point pressure therapy group and the Chinese herb group (all <0.05).@*CONCLUSION@#The auricular gold-needle therapy achieves the significant therapeutic effects on chronic fatigue syndrome of deficiency constitution and its mechanism is probably related to the regulation of immune function.

Acupuncture Therapy , Fatigue Syndrome, Chronic , Gold , Humans , Qi , Treatment Outcome
Bogotá; Instituto Nacional de Salud; [2019]. 4 p.
Monography in Spanish | PIE, LILACS, PIE | ID: biblio-1047552


La minería de oro a cielo abierto se ha asociado a diversos problemas de salud en la población, entre esos la proliferación de enfermedades infecciosas como la malaria. El departamento del Chocó, uno de los más importantes productores de oro del país, ha venido siendo afectado por un aumento en el número de casos y muertes por Malaria. Con el fin de poner a prueba si estos dos eventos se encuentran relacionados el ONS llevó a cabo un estudio para evaluar la asociación entre los niveles de producción de oro en los municipios del Chocó y los casos de malaria. El estudio encontró que los municipios con mayor producción de oro también presentan en promedio el mayor número de casos de malaria anualmente. De acuerdo con los hallazgos de este y otros estudios es importante para el control de la malaria abrir los espacios necesarios para discutir la minería de oro como un factor determinante en la propagación de la malaria en el departamento del Chocó y probablemente otras regiones mineras de Colombia.

Gold , Malaria/epidemiology , Mining , Epidemiologic Factors , Risk Factors , Colombia , Malaria/etiology , Malaria/prevention & control
Biosci. j. (Online) ; 34(6): 1477-1487, nov.-dec. 2018.
Article in English | LILACS | ID: biblio-968927


The large surface stacking volume of waste and tailings at the Serra Pelada gold mine, with a high content of potentially toxic elements (PTEs), has led to environmental damage in the area, which continues to this day and is yet to be measured. Total and available Cu, Mo, Pb, and Zn and an indicator index was formulated for soil contamination in the artisanal mining area of Serra Pelada, Amazônia, Brazil. To obtain these data, six soil samples were collected surrounding the lake formed from the mining trenches and one from a forest area outside the influence of mining activities. Metal solubilization and partial extraction were conducted by aqua regia and 0.5 mol L-1 HCl, respectively, followed by detection using argon plasma optical emission spectrometry. All PTEs showed total contents above the quality reference values for soils in the state of Para. The available fractions of Cu, Pb, and Zn were higher than the concentrations expected for Para in forest soils. The total Cu contents were above the value of prevention defined by the National Council of Environment. In general, there was Mo enrichment (41.0) > Cu (3.5) > Pb (1.4), indicating that the areas had been contaminated by PTEs a resulting from human activity.

O empilhamento superficial de volume expressivo de rejeito e estéril, com alto teor de elementos potencialmente tóxicos causou danos ambientais até hoje não mensurados. Neste contexto, constituiu-se objetivo deste trabalho, avaliar os teores totais e disponíveis de Cu, Mo, Pb e Zn e determinar índices indicadores de contaminação em solos na área de exploração artesanal de Au em Serra Pelada -Amazônia, Brasil. Para tanto, foram coletados seis pontos amostrais no entorno do lago formado a partir da cava e um ponto em área de mata sem influência do garimpo. Os teores totais e disponíveis dos metais foram extraídos com água régia e solução 0,5 mol L-1 HCl respectivamente, seguidos das determinações através da espectrometria de emissão ótica com plasma de argônio acoplado indutivamente (ICP-OES). Todos os PTEs apresentaram teores totais acima dos valores de referência de qualidade para solos do estado do Pará. Os teores disponíveis de Cu, Pb e Zn foram superiores aos observados em solos de área de floresta do estado do Pará. Os teores de Cu total estão acima do valor de prevenção definido pelo Conselho Nacional de Meio Ambiente. Em média houve enriquecimento de Mo (41,0) > Cu (3,5) > Pb (1,4), o que indica que as áreas foram contaminadas por PTEs a partir das atividades antrópicas.

Soil , Chemical Contamination , Toxic Substances , Metals, Heavy , Gold , Mining
Braz. j. microbiol ; 49(1): 29-37, Jan.-Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-889196


ABSTRACT Increased environmental pollution has necessitated the need for eco-friendly clean-up strategies. Filamentous fungal species from gold and gemstone mine site soils were isolated, identified and assessed for their tolerance to varied heavy metal concentrations of cadmium (Cd), copper (Cu), lead (Pb), arsenic (As) and iron (Fe). The identities of the fungal strains were determined based on the internal transcribed spacer 1 and 2 (ITS 1 and ITS 2) regions. Mycelia growth of the fungal strains were subjected to a range of (0-100 Cd), (0-1000 Cu), (0-400 Pb), (0-500 As) and (0-800 Fe) concentrations (mgkg-1) incorporated into malt extract agar (MEA) in triplicates. Fungal radial growths were recorded every three days over a 13-days' incubation period. Fungal strains were identified as Fomitopsis meliae, Trichoderma ghanense and Rhizopus microsporus. All test fungal exhibited tolerance to Cu, Pb, and Fe at all test concentrations (400-1000 mgkg-1), not differing significantly (p > 0.05) from the controls and with tolerance index >1. T. ghanense and R. microsporus demonstrated exceptional capacity for Cd and As concentrations, while showing no significant (p > 0.05) difference compared to the controls and with a tolerance index >1 at 25 mgkg-1 Cd and 125 mgkg-1 As. Remarkably, these fungal strains showed tolerance to metal concentrations exceeding globally permissible limits for contaminated soils. It is envisaged that this metal tolerance trait exhibited by these fungal strains may indicate their potentials as effective agents for bioremediative clean-up of heavy metal polluted environments.

Fungi/isolation & purification , Fungi/metabolism , Metals, Heavy/metabolism , Soil Pollutants/metabolism , Cadmium/analysis , Cadmium/metabolism , Copper/analysis , Copper/metabolism , Fungi/classification , Fungi/genetics , Gold/analysis , Gold/metabolism , Metals, Heavy/analysis , Mining , Phylogeny , Soil Pollutants/analysis
Article in Chinese | WPRIM | ID: wpr-775300


OBJECTIVE@#To investigate the rapid and accurate method for the detection of dengue virus (DENV) by using nicking enzyme assisted strand-displacement amplification (SDA) combined with gold nanoparticles-based lateral flow strip.@*METHODS@#Total RNA of the virus was extracted by using magnetic beads method and transcribed to cDNA for SDA detection system. Nicking enzyme-assisted method was used for detecting DENV, and agarose gel electrophoresis was used for analyzing the sensitivity of SDA amplification products. A gold nanoparticles-based lateral flow strip was developed based on the principle of nucleic acid base complementary pairing to design the test line and control line. The gold particles were prepared by using sodium citrate reduction method for gold nanoparticles-based lateral flow strip construction.@*RESULTS@#The sensitivity of the SDA method was 10 fmol/L, and the sensitivity of gold nanoparticles-based lateral flow strip based on SDA method was also 10 fmol/L. In a linear range from 10 fmol/L to 10 fmol/L, the corresponding linear correlation coefficient () of DENV was 0.98. The specificity of nanoparticles-based lateral flow strip based on SDA for DENV detection was high, which was no crossing with other control groups.@*CONCLUSIONS@#A gold nanoparticles-based lateral flow strip based on SDA method for DENV detection has been established, which is convenient, fast, and the result is visible to naked eyes.

Dengue , Diagnosis , Dengue Virus , Gold , Humans , Metal Nanoparticles , Reproducibility of Results , Sensitivity and Specificity
Electron. j. biotechnol ; 29: 86-93, sept. 2017. graf, ilus
Article in English | LILACS | ID: biblio-1017388


Background: Although nanoparticles (NPs) have many advantages, it has been proved that they may be absorbed by and have toxic effects on the human body. Recent research has tried to evaluate and compare the nanotoxicity of gold nanoparticles (AuNPs) produced by two types of microorganisms in vitro by two different methods. AuNPs were produced by Bacillus cereus and Fusarium oxysporum, and their production was confirmed by visible spectral, transmission electron microscope, and X-ray diffraction (XRD) analyses. The human fibroblast cell line CIRC-HLF was treated with AuNPs, and the induced nanotoxicity was measured using direct microscopic and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Results: The results showed that the produced AuNPs had a maximum absorbance peak around 510­530 nanometer (nm), with spherical, hexagonal, and octagonal shapes and average sizes around 20­50 nm. The XRD results confirmed the presence of GNPs in the microbial culture supernatants. An MTT assay showed that GNPs had dose-dependent toxic effects, and microscopic analysis showed that GNPs induced cell abnormalities in doses lower than the determined half-maximal inhibitory concentrations (IC50s). Conclusions: In conclusion, the biologically produced AuNPs had toxic effects in the cell culture, and direct techniques such as microscopic evaluation instead of indirect methods such as MTT assay were more useful for assessing the nanotoxicity of the biologically produced AuNPs. Thus, the use of only MTT assay for nanotoxicity evaluation of AuNPs is not desirable.

Nanoparticles/metabolism , Nanoparticles/toxicity , Gold/metabolism , Gold/toxicity , Spectrophotometry , Bacillus cereus/metabolism , Cells, Cultured , Gold Compounds/metabolism , Gold Compounds/toxicity , Toxicity Tests , Surface Plasmon Resonance , Nanotechnology , Microscopy, Electron, Transmission , Metal Nanoparticles/toxicity , Fusarium/metabolism
Braz. J. Pharm. Sci. (Online) ; 53(4): e00191, 2017. tab, graf, ilus
Article in English | LILACS | ID: biblio-889433


ABSTRACT The enhancement of anti-leukemia therapy and the treatment of infections caused by multidrug-resistant pathogens are major challenges in healthcare. Although a large arsenal of drugs is available, many of these become ineffective, and as a result, the discovery of new active substances occurs. Notably, triazenes (TZCs) have been consolidated as a promising class of compounds, characterized by significant biological activity, especially antiproliferative and antimicrobial properties. The aim of this study is the synthesis and characterization of a new triazenide complex of gold (I), as well as the in vitro assessment of its antiproliferative activity against the K562 cell line (Chronic Myeloid Leukemia), and antibacterial activity against bacterial isolates of biofilm-producing coagulase-negative staphylococci. The combination of TZC with gold metal tends to have a synergistic effect against all biofilm-producing isolates, with Minimum Inhibitory Concentration values (MIC) between 32 and 64 µg mL-1. It has also shown activity against K562 cell line, getting an IC50=4.96 µM. Imatinib mesylate (Glivec) was used as reference, with IC50=3.86 µM. To the best of our knowledge, this study represents the first report of the activity of a TZC complexed with gold ion in the oxidation state (I) against microorganisms that produce biofilm and K562 cells.

Triazenes/chemical synthesis , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Gold/classification , Triazenes/analysis , Triazenes/therapeutic use
Arab Journal of Gastroenterology. 2017; 18 (2): 83-86
in English | IMEMR | ID: emr-189170


Background and study aims: Percutaneous placement of fiducial markers is required to perform stereotactic body radiation therapy [SBRT] for liver neoplastic lesions. This prospective trial was designed to evaluate the feasibility and safety of percutaneous ultrasound-guided placement of three different types of markers in patients with liver cancer referred for SBRT

Patients and methods: Fifty patients underwent percutaneous ultrasound-guided implantation of a fiducial marker in the liver. Three sizes of needles were used: 25 gauge [G], 22 G, and 17 G. The 25 G and 22 G needles contained gold anchor markers of 0.28 x 10 mm and 0.4 x 10 mm size, respectively. In contrast, the 17 G needle contained a gold grain marker of 1 x 4 mm. Each patient received 1-6 markers, depending on lesion size and numbers. Technical feasibility and the occurrence of adverse events were registered. Computed tomography scans were acquired prior to SBRT to evaluate the location, visibility, or complications related to the markers

Results: A total of 163 needles were used to deliver 163 markers in 50 patients. No major complications occurred. Minor complication occurrence rate was 12%. The total complication occurrence for all type of markers was 8.5%. No complications were observed with the use of the gold anchor marker of 0.4 x 10 mm size. Variance analysis of the three markers showed a significant difference in the frequency of complications amongst the three markers [p < 0.01]

Conclusion: Percutaneous ultrasound-guided placement of fiducial markers for SBRT of liver neoplastic lesions is safe and feasible. In our series, the 22 G needle showed some advantage in terms of handling and safety when compared with the 25 G and 17 G needles. In addition, the gold anchor marker of 0.4 x 10 mm size displayed a lower percentage of displacement

Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Radiosurgery , Liver Neoplasms , Ultrasonography , Gold , Needles , Robotics , Prospective Studies
Braz. oral res. (Online) ; 31: e64, 2017. tab, graf
Article in English | LILACS | ID: biblio-952106


Abstract The aim of this systematic review was to compare the clinical performance and failure modes of teeth restored with intra-radicular retainers. A search was performed on PubMed/Medline, Central and ClinicalTrials databases for randomized clinical trials comparing clinical behavior and failures of at least two types of retainers. From 341 detected papers, 16 were selected for full-text analysis, of which 9 met the eligibility criteria. A manual search added 2 more studies, totalizing 11 studies that were included in this review. Evaluated retainers were fiber (prefabricated and customized) and metal (prefabricated and cast) posts, and follow-up ranged from 6 months to 10 years. Most studies showed good clinical behavior for evaluated intra-radicular retainers. Reported survival rates varied from 71 to 100% for fiber posts and 50 to 97.1% for metal posts. Studies found no difference in the survival among different metal posts and most studies found no difference between fiber and metal posts. Two studies also showed that remaining dentine height, number of walls and ferrule increased the longevity of the restored teeth. Failures of fiber posts were mainly due to post loss of retention, while metal post failures were mostly related to root fracture, post fracture and crown and/or post loss of retention. In conclusion, metal and fiber posts present similar clinical behavior at short to medium term follow-up. Remaining dental structure and ferrule increase the survival of restored pulpless teeth. Studies with longer follow-up are needed.

Humans , Post and Core Technique , Tooth, Nonvital/therapy , Dental Restoration Failure , Dental Restoration, Permanent/methods , Titanium , Bias , Randomized Controlled Trials as Topic , Treatment Outcome , Glass/chemistry , Gold/chemistry
Mem. Inst. Oswaldo Cruz ; 111(1): 59-66, Jan. 2016. tab, graf
Article in English | LILACS | ID: lil-771078


Gold-mining may play an important role in the maintenance of malaria worldwide. Gold-mining, mostly illegal, has significantly expanded in Colombia during the last decade in areas with limited health care and disease prevention. We report a descriptive study that was carried out to determine the malaria prevalence in gold-mining areas of Colombia, using data from the public health surveillance system (National Health Institute) during the period 2010-2013. Gold-mining was more prevalent in the departments of Antioquia, Córdoba, Bolívar, Chocó, Nariño, Cauca, and Valle, which contributed 89.3% (270,753 cases) of the national malaria incidence from 2010-2013 and 31.6% of malaria cases were from mining areas. Mining regions, such as El Bagre, Zaragoza, and Segovia, in Antioquia, Puerto Libertador and Montelíbano, in Córdoba, and Buenaventura, in Valle del Cauca, were the most endemic areas. The annual parasite index (API) correlated with gold production (R2 0.82, p < 0.0001); for every 100 kg of gold produced, the API increased by 0.54 cases per 1,000 inhabitants. Lack of malaria control activities, together with high migration and proliferation of mosquito breeding sites, contribute to malaria in gold-mining regions. Specific control activities must be introduced to control this significant source of malaria in Colombia.

Humans , Gold , Mining , Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology , Colombia/epidemiology , Geography , Prevalence , Retrospective Studies
Bahrain Medical Bulletin. 2016; 38 (2): 125-125
in English | IMEMR | ID: emr-178838


Objective: To measure the nonlinear refractive index and nonlinear absorption coefficient of Ag and Au particles

Design: A Quantitative Measurements

Setting: Royal College of Surgeons in Ireland [RCSI], Kingdom of Bahrain

Method: Ag and Au colloidal solutions were prepared by reduction processes. The nonlinear properties of the samples were investigated using CW laser at 488-514 nm using Z-scan technique

Result: Closed aperture z-scan displayed a pre-focal peak followed by a post-focal valley. These materials showed a large negative nonlinear refractive index of 5.85 X 10[-11] m[2]/W and 3.32 X 10[12]m[2]/W for silver and gold respectively and negative nonlinear absorption of 3.45 x 10[-4]m/W and 7.48 x 10[+5] m/W for silver and gold respectively

Conclusion: Z-scan showed that Ag and Au nanoparticles exhibit a nonlinear effect of thermal origin

Gold , Silver , Refractometry
Chinese Journal of Biotechnology ; (12): 447-456, 2016.
Article in Chinese | WPRIM | ID: wpr-337452


Surface enhanced Raman spectroscopy technology (SERS), using gold nanoparticles as a base, was developed for rapid and sensitive detection of virus strains. SERS can be used as a rapid and reliable method to distinguish the titers of viral replication. In the present study, we characterized H1N1 subtypes of influenza A virus strains in different conditions of pH or temperatures, while we analyzed data from SERS technology using gold nanoparticles as a base and cell cultures were employed to further confirm the data from virus strains. Origin8.0 was used to collect Raman spectra, smooth and homogenize data, and to contrast spectra. Our results indicated that the peaks of different virus strains in optimal environmental conditions (T=37 ℃/pH=7.2) reached ≥3 000. This criterion was verified by subsequent virological method. The present data indicate that the established SERS protocol can be used as a rapid and reliable method to distinguish the replication rate of virus, which can be further used in clinical samples.

Gold , Hydrogen-Ion Concentration , Influenza A Virus, H1N1 Subtype , Nanoparticles , Spectrum Analysis, Raman , Temperature , Virus Cultivation , Methods