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1.
Eur Radiol ; 33(5): 3103-3114, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36571605

RESUMEN

OBJECTIVES: The pandemic caused by SARS-CoV-2 has led to the rapid publication of numerous radiology articles, primarily focused on disease diagnosis. The objective of this study is to analyze the intellectual structure of radiology research on COVID-19 using a citation and co-citation analysis. METHODS: We identified all documents about COVID-19 published in radiology journals included in the Web of Science in the period 2020-2021, conducting a citation analysis. Then we identified all bibliographic references that were cited by these documents, generating a co-citation matrix that was used to perform a co-citation network. RESULTS: Of the 3418 documents indexed in WoS, 857 were initially "Early Access," 2223 had citations, 393 had more than 20 citations, and 83 had more than 100 citations. The USA had the highest number of publications (32.62%) and China had the highest rate of funded studies (45.38%). The three authors with the most publications were affiliated with Italian institutions, while the five most cited authors were Chinese. A total of 647 publications were co-cited at least 12 times and were published in 206 different journals, with 49% of the documents found in radiology journals. The institutions with the greatest presence among these co-cited articles were Chinese and American. CONCLUSION: This co-citation analysis is the first to focus exclusively on radiology articles on COVID-19. Our study confirms the existence of interrelated thematic clusters with different specific weights. KEY POINTS: • As the pandemic caused by SARS-Cov-2 has led to the rapid publication of numerous radiology studies in a short time period, a bibliometric review based on citation and co-citation analysis has been conducted. • The co-citation analysis supported the identification of key themes in the study of COVID-19 in radiology publications. • Many of the most co-cited articles belong to a heterogeneous group of publications, with authors from countries that are far apart and even from different disciplines.


Asunto(s)
COVID-19 , Publicaciones Periódicas como Asunto , Radiología , Humanos , Estados Unidos , SARS-CoV-2 , Bibliometría
2.
Eur Surg Res ; 56(3-4): 164-79, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27035593

RESUMEN

BACKGROUND: Renal injuries are relatively frequent in abdominal trauma. In some cases, adhesives and sealants can be used to repair and preserve injured organs. This paper describes the behaviour of three biomaterials - TachoSil®, GelitaSpon®, and a new elastic cyanoacrylate (CyA), Adhflex® - in standardized experimental renal injuries. METHODS: Ninety male Wistar rats (300-350 g) were used. A Stiefel Biopsy Punch (8 mm diameter, 3 mm depth) was used to create injuries to the anterior kidney to evaluate wound healing. The animals were divided into five groups: (1) sham (n = 3); (2) control (n = 6), untreated, standard punch injury created on the anterior left kidney; (3) TachoSil® (n = 27), punch injury treated with TachoSil®; (4) GelitaSpon® (n = 27), punch injury treated with GelitaSpon®, and (5) Adhflex® (n = 27), punch injury treated with the new elastic CyA adhesive. The parameters studied were bleeding time, peritoneal adhesions, and histopathological evaluation of wound healing on days 2, 6, and 18, including measurements of the gap between wound edges, inflammatory reaction (CD68), and vascular neoformation (CD31). RESULTS: The bleeding time was significantly shorter (27.7 ± 12.9 s) in the Adhflex® group than in the control (135.8 ± 11.6 s; p < 0.01), TachoSil® (77.5 ± 7.4 s; p < 0.05), and GelitaSpon® (82.5 ± 14.4 s; p < 0.05) groups. The incidence of intraperitoneal adhesions in the animals treated with Adhflex® was 3.6 times higher than in the non-treated group. It was also higher (p < 0.04) than in the groups treated with TachoSil® and GelitaSpon®. The time point with the largest gap between the wound edges and most abundant granulation tissue was at day 6. The largest gap after 18 days was reported for the Adhflex® adhesive. With regard to the markers CD31 and CD68, Adhflex® showed the largest areas 2 days after surgery, but no differences were found after 6 and 18 days versus the other treatments. The expression of the immunomarkers on the renal samples treated with Adhflex® was consistent with a normal healing process. CONCLUSIONS: In this experimental model of renal injuries, the new elastic CyA (Adhflex®) resulted in the shortest bleeding time. It offers rapid sealing of the bleeding produced by renal injuries, fixation to adjacent tissues, and reduced occurrences of relapse. The evolution of the scarring is similar to other procedures. Given that traumatic renal injuries are always an emergency due to haemorrhage, Adhflex® might offer additional benefits over conventional treatment methods in human clinical practice.


Asunto(s)
Celulosa/farmacología , Cianoacrilatos/farmacología , Fibrinógeno/farmacología , Riñón/lesiones , Trombina/farmacología , Adhesivos Tisulares/farmacología , Cicatrización de Heridas , Animales , Tiempo de Sangría , Combinación de Medicamentos , Inmunohistoquímica , Riñón/patología , Modelos Logísticos , Masculino , Ratas , Ratas Wistar , Adherencias Tisulares/epidemiología
3.
Surg Today ; 45(8): 939-56, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25344231

RESUMEN

This paper presents a review of the use of cyanoacrylate adhesives (CA) in general surgery and digestive surgery, studies the mechanisms of action and interactions of CAs in adherent tissues, and compiles data on the latest experimental and clinical applications. More than seven million traumatic injuries are estimated to occur every year, and between 26 and 90 million surgical procedures using different techniques are performed to close the resulting wounds. Traditional methods not only are both useful and effective, but also have some drawbacks. This review covers a considerable number of surgical procedures for which CAs had satisfactory results. The adhesive facilitated the healing of very diverse tissues, such as solid organs, vascular tissue or the abdominal wall. In other cases, no significant differences were found when CA was compared to traditional methods, with the adhesive standing out as a simple and reliable solution. The number of procedures in which CA was detrimental was very low. This review also collects and describes these. In conclusion, the surgical fields and procedures in which CA was successfully used are highly diverse. This review will allow physicians to determine which techniques were first used experimentally, but finally settled in clinical practice as feasible alternatives to standard treatments.


Asunto(s)
Cianoacrilatos/uso terapéutico , Procedimientos Quirúrgicos Operativos/métodos , Adhesivos Tisulares/uso terapéutico , Técnicas de Cierre de Heridas , Cianoacrilatos/administración & dosificación , Cianoacrilatos/farmacología , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Embolización Terapéutica , Enbucrilato , Hemostáticos , Herniorrafia , Humanos , Laparoscopía , Adhesivos Tisulares/administración & dosificación , Adhesivos Tisulares/farmacología , Várices/terapia , Procedimientos Quirúrgicos Vasculares/métodos , Cicatrización de Heridas , Heridas y Lesiones/cirugía
4.
Biofouling ; 30(4): 501-11, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24673176

RESUMEN

The aim of this work was to investigate the production of extracellular polymeric substances (EPS) by Aeromonas hydrophila grown under anaerobic conditions. EPS composition was studied for planktonic cells, cells attached to carbon fibre supports using a soluble ferric iron source and cells grown with a solid ferric iron mineral (gossan). Conventional spectrophotometric methods, Fourier transform infrared (FTIR) and confocal laser scanning microscopy (CLSM) were used to determine the main components in the biofilm extracted from the cultures. The key EPS components were proteins, indicating their importance for electron transfer reactions. Carbohydrates were observed mostly on the mineral and contained terminal mannosyl and/or terminal glucose, fucose and N-acetylgalactosamine residues.


Asunto(s)
Aeromonas hydrophila/metabolismo , Polímeros/metabolismo , Biopelículas , Microscopía Confocal , Polímeros/análisis , Polímeros/química , Espectroscopía Infrarroja por Transformada de Fourier
5.
Acta Med Litu ; 31(1): 61-67, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38978869

RESUMEN

22-year-old male diagnosed with Tuberous Sclerosis Complex (TSC), a genetic disorder characterized by benign tumors in various organs, with a focus on neurological implications. Central to the study is the development of Subependymal Giant Cell Astrocytomas (SEGAs), leading to hydrocephalus in the patient. The diagnosis of TSC was made in the patient's childhood, and he was monitored regularly. The study highlights a significant growth in a subependymal nodule, leading to monoventricular hydrocephalus. MRI scans played a crucial role in identifying the progression of SEGAs and the subsequent hydrocephalus. The treatment approach involved endoscopic surgical removal of the SEGA, with histopathology confirming the diagnosis. Post-surgical outcomes over an eight-year follow-up period showed a normalization in ventricular size and the stability of other subependymal nodules, without any complications. This case underscores the importance of regular monitoring for TSC patients, early intervention for complications like hydrocephalus, and the need for a multidisciplinary treatment approach. The case study provides valuable insights into the management of neurodevelopmental disorders and the complexities surrounding TSC and SEGAs.

6.
Prep Biochem Biotechnol ; 43(8): 815-27, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23876140

RESUMEN

The sorption of Fe(II) and Fe(III) by extracellular polymeric substances (EPS) of acidophilic bacteria Acidiphilium 3.2Sup(5) and Acidithiobacillus ferrooxidans, harvested from the ecosystem of the Tinto River (Huelva, Spain), was investigated. EPS from mixed cultures of both bacteria (EPS(mixed)) and pure cultures of A. 3.2Sup(5) (EPS(pure)) were extracted with ethylenediamine tetraacetic acid (EDTA) and were characterized by Fourier-transform infrared (FTIR), electron photoemission (XPS), x-ray diffraction (DRX), and energy dispersive x-ray (EDX) spectroscopy and scanning electron microscopy (SEM). EPS pure were loaded, in sorption tests, with Fe(II) and Fe(III). The results obtained indicate that the biochemical composition and structure of EPS(mixed) was very similar to that of EPS(pure). Besides, results indicate that EPS(mixed) adsorbed Fe(II) and Fe(III) by preferential interaction with the carboxyl group, which favored the formation of Fe(II)/Fe(III) oxalates. These species were also formed in EPS(pure) loaded with Fe(II)/Fe(III). All this behavior suggested that the sorption of iron by EPS(mixed) was similar to sorption of EPS(pure), which fitted the Freundlich model. Thus, the iron uptake of EPS(mixed) reached 516.7 ± 23.4 mg Fe/g-EPS at an initial concentration of 2.0 g/L of Fe(total) and Fe(II)/Fe(III) ratio of 1.0.


Asunto(s)
Proteínas Bacterianas/química , Compuestos Férricos/química , Compuestos Ferrosos/química , Polisacáridos Bacterianos/química , Acidiphilium/química , Acidiphilium/ultraestructura , Acidithiobacillus/química , Acidithiobacillus/ultraestructura , Adsorción , Proteínas Bacterianas/aislamiento & purificación , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Polisacáridos Bacterianos/aislamiento & purificación , Ríos/microbiología , Espectroscopía Infrarroja por Transformada de Fourier
7.
Cir Esp ; 90(2): 114-20, 2012 Feb.
Artículo en Español | MEDLINE | ID: mdl-22225611

RESUMEN

INTRODUCTION: The aim of the study is to evaluate the limb salvage rate achieved by treating locally advanced extremity sarcoma and melanoma by hyperthermic isolated limb perfusion with melphalan and TNF-α (ILP-MT). MATERIAL AND METHODS: A retrospective study was conducted on patients suffering from locally advanced soft tissue sarcoma and melanoma of the limb and treated by means of ILP-MT between November 2001 and February 2010. The response rate, toxicity, complications, disease free intervals, overall survival and limb salvage rate were evaluated. RESULTS: A total of 30 patients (19 females and 11 males) with a median age of 60 years (14-82) were treated by this technique. The overall response rate was 93.4% (complete, 46.7%; partial 46.7%); the mean follow-up was 23 months. The median duration of response was 5 months (0-62), The median overall survival was 13.5 months (range 1 - 62). Limb salvage rate was 86.7%. Eleven patients are currently alive (5 without disease, 2 with residual disease on treatment, 2 with local progression and 2 with systemic progression). CONCLUSION: With the use of ILP-MT we have avoided the amputation of 26 limbs affected by locally advanced sarcoma or melanoma. ILP-MT is feasible and safe in a multidisciplinary environment.


Asunto(s)
Antineoplásicos Alquilantes/administración & dosificación , Brazo , Quimioterapia del Cáncer por Perfusión Regional , Hipertermia Inducida , Pierna , Recuperación del Miembro , Melanoma/tratamiento farmacológico , Melfalán/administración & dosificación , Sarcoma/tratamiento farmacológico , Neoplasias de los Tejidos Blandos/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia del Cáncer por Perfusión Regional/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
8.
Cureus ; 13(7): e16295, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34381653

RESUMEN

Posterior reversible encephalopathy syndrome is an increasingly recognized disorder characterized by a headache, visual disturbances, and seizures. It is a reversible neurotoxic state, with multiple risk factors in which endothelial injury and compromised brain perfusion are the common characteristics. Diagnosis is usually made by cerebral magnetic resonance imaging that typically shows early-stage bilateral symmetrical parieto-occipital hyperintensities on T2 and fluid-attenuated inversion recovery (FLAIR) sequences. However, other locations have been described where the disease may appear less frequently. We describe the case of a 62-year-old man, with a medical history of hypertension, who presented with anisocoria with mydriatic non-reactive pupil and ptosis of the left eye. CT head showed a slightly hypodense brainstem, in relation to vasogenic edema. This was confirmed with magnetic resonance imaging. The angiography did not identify cerebral artery aneurysms. The symptoms and radiological findings were almost completely reversible after improving the patient's blood pressure. This case highlights a rare single presentation of posterior reversible encephalopathy syndrome associated with subarachnoid hemorrhage. A high index of suspicion, careful examination, and exploration with imaging techniques were essential to reach this diagnosis.

9.
BMJ Case Rep ; 14(11)2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34753729

RESUMEN

Primary neuroendocrine tumours of the kidney are rare, and their pathophysiology is uncertain; since their discovery in 1966, they have been described only a few times in the literature. We present a case of a well-differentiated neuroendocrine tumour of the kidney in an asymptomatic patient, which required a multidisciplinary approach by the hospital's team, including precise surgical treatment and an effective radiopathological diagnosis. The patient underwent right radical nephrectomy. During follow-up, he remained asymptomatic, and no metastases or complications were identified.


Asunto(s)
Neoplasias Renales , Tumores Neuroendocrinos , Humanos , Riñón/diagnóstico por imagen , Riñón/cirugía , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/cirugía , Masculino , Nefrectomía , Tumores Neuroendocrinos/diagnóstico por imagen , Tumores Neuroendocrinos/cirugía
11.
Sci Total Environ ; 598: 856-866, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-28458203

RESUMEN

The aim of this work was to demonstrate the feasibility of the application of biosorption in the treatment of metal polluted wastewaters through the development of several pilot plants to be implemented by the industry. The use as biosorbents of both the brown seaweed Fucus vesiculosus and a sugar beet pulp was investigated to remove heavy metal ions from a wastewater generated in an electroplating industry: Industrial Goñabe (Valladolid, Spain). Batch experiments were performed to study the effects of pH, contact time and initial metal concentration on metal biosorption. It was observed that the adsorption capacity of the biosorbents strongly depended on the pH, increasing as the pH rises from 2 to 5. The adsorption kinetic was studied using three models: pseudo first order, pseudo second order and Elovich models. The experimental data were fitted to Langmuir and Freundlich isotherm models and the brown alga F. vesiculosus showed higher metal uptake than the sugar beet pulp. The biomasses were also used for zinc removal in fixed-bed columns. The performance of the system was evaluated in different experimental conditions. The mixture of the two biomasses, the use of serial columns and the inverse flow can be interesting attempts to improve the biosorption process for large-scale applications.

12.
Methods Mol Biol ; 1224: 163-76, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25416257

RESUMEN

Development of a system for direct transfer of antifungal candidate genes into European chestnut (Castanea sativa) would provide an alternative approach to conventional breeding for production of chestnut trees that are tolerant to ink disease caused by Phytophthora spp. Overexpression of genes encoding PR proteins (such as thaumatin-like proteins), which display antifungal activity, may represent an important advance in control of the disease. We have used a chestnut thaumatin-like protein gene (CsTL1) isolated from European chestnut cotyledons and have achieved overexpression of the gene in chestnut somatic embryogenic lines used as target material. We have also acclimatized the transgenic plants and grown them on in the greenhouse. Here, we describe the various steps of the process, from the induction of somatic embryogenesis to the production of transgenic plants.


Asunto(s)
Fagaceae/crecimiento & desarrollo , Fagaceae/genética , Ingeniería Genética/métodos , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/crecimiento & desarrollo , Técnicas de Cocultivo , Fagaceae/fisiología , Regeneración , Semillas/crecimiento & desarrollo , Transformación Genética
13.
IET Nanobiotechnol ; 9(5): 252-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26435277

RESUMEN

This study focuses on the green synthesis of noble metal nanoparticles (silver (Ag) and platinum (Pt)) and how the size and shape of the nanoparticles produced can be controlled through changes in the initial pH value of the precursor solution. The nanoparticles were characterised by ultra-violet-visible spectroscopy, transmission electron microscopy and X-ray diffraction. This simple and environmentally friendly method allows the synthesis of diverse nanostructures in the absence of a surfactant or polymer to direct nanoparticle growth, and without externally adding seed crystallites. The antibacterial effects of Ag nanoparticles and catalytic properties of Pt nanoparticles were explored for future promising biotechnological approaches in different fields.


Asunto(s)
Biotecnología/métodos , Citrus sinensis/química , Nanopartículas del Metal/química , Extractos Vegetales/metabolismo , Platino (Metal)/química , Plata/química , Aeromonas/efectos de los fármacos , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacología , Viabilidad Microbiana/efectos de los fármacos , Extractos Vegetales/química , Platino (Metal)/metabolismo , Platino (Metal)/farmacología , Plata/metabolismo , Plata/farmacología
14.
Am J Case Rep ; 16: 491-5, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26212619

RESUMEN

BACKGROUND Primary malignant melanoma of the esophagus (PMME) is a rare cancer with a poor prognosis. It is often difficult to differentiate from non-epithelial malignant tumors, and immunohistochemical staining may be needed to diagnose the condition. The mainstay of treatment is usually surgical with curative or palliative intent, since radio- and chemotherapy do not really improve the outcome. The average survival rate after surgery is 34.5 months. At the time of diagnosis, 40-80% of cases have local regional lymph node metastases. CASE REPORT The case of a 67-year-old male patient with PMME is reported. He presented with progressive dysphagia. A computerized tomography was performed in which a polypoid mass was observed in the distal esophagus. It was originally suspected to be an adenocarcinoma, but was subsequently correctly diagnosed by immunohistochemical staining with HMB-45 antibody and by the presence of S-100 protein. A subtotal esophagectomy was performed. CONCLUSIONS Very few cases of PMME have been reported in the literature and there is only limited clinical experience with this disease. Therefore, it is very difficult to establish clear criteria for clinical recognition of this type of melanoma. Early histopathological confirmation of the character is essential for further treatment in case of confirmation of malignancy.


Asunto(s)
Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/terapia , Melanoma/diagnóstico , Melanoma/terapia , Anciano , Humanos , Masculino
15.
Tree Physiol ; 23(9): 633-40, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12750056

RESUMEN

A full-length cDNA clone named QRCPE (Quercus robur crown preferentially expressed) that is differentially expressed during in vitro culture of mature and juvenile-like shoots of Quercus robur L. was identified by differential display. The deduced amino acid sequence showed that the encoded protein is small, contains a predicted N-terminal hydrophobic signal peptide that targets the protein to the cell wall, and is rich in glycine and histidine residues. Accumulation of QRCPE mRNA was higher in oak microshoots derived from crown branch shoot cultures than in oak microshoots derived from basal shoot cultures at the end of the multiplication and rooting period. Among organs, the highest accumulation of QRCPE transcripts was detected in roots, followed by stems and leaves, with preferential accumulation in specific organs of ontogenetically older shoots. Although QRCPE mRNA was abundant in oak zygotic and somatic embryos, almost no QRCPE mRNA accumulation was detected in nodular callus cells, suggesting a possible role of this gene in embryonic development. In proliferating shoot cultures of two chestnut (Castanea sativa Mill.) clones, the QRCPE homolog was preferentially expressed in crown-derived shoots. On the other hand, expression analysis of QRCPE in juvenile and mature material from soil-grown oak plants indicated that this gene is expressed from the embryonic to mature phases, but is progressively down-regulated during plant maturation. In vitro culture conditions induced changes in QRCPE transcript abundance in both basal and crown shoots in a phase-dependent manner. We conclude that QRCPE expression in oak is correlated with the ontogenetic stage of shoots, and thus this gene may be useful as a potential molecular marker for maturation-related characteristics.


Asunto(s)
Brotes de la Planta/genética , Quercus/genética , Árboles/genética , Aesculus/genética , Secuencia de Aminoácidos , Secuencia de Bases , ADN Complementario/genética , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Datos de Secuencia Molecular
16.
Cryo Letters ; 25(1): 33-42, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15031743

RESUMEN

This work describes experiments demonstrating the feasibility of long-term conservation of Castanea sativa germplasm through cryopreservation of embryonic axes or somatic embryo clumps. Between 93 % and 100 % of excised embryonic axes of recalcitrant chestnut seeds survived storage in liquid nitrogen (LN) following desiccation in a laminar flow cabinet to moisture contents of 20-24 % (on a fresh weight basis), and some 63 % subsequently developed as whole plants. Desiccation to moisture contents less than 19 % produced damage resulting in loss of organized plant development after cryostorage, allowing only root growth. When 6-8 mg clumps of globular or heart-shaped somatic embryos were precultured for 7 days on high-sucrose medium and then desiccated to a moisture content of 25 % before storage in LN, the embryogenesis resumption level after thawing was 33 %. When the embryo clumps were precultured for 3 days on high-sucrose medium followed by 60 min application of PVS2 vitrification solution before cryostorage, the post-storage embryogenesis resumption level was 68 %.


Asunto(s)
Criopreservación/métodos , Fagaceae/embriología , Semillas/fisiología , Crioprotectores/farmacología , Desecación/métodos , Fagaceae/efectos de los fármacos , Germinación/efectos de los fármacos , Germinación/fisiología , Semillas/efectos de los fármacos
17.
Res Microbiol ; 165(9): 794-802, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25283724

RESUMEN

Aeromonas hydrophila is a facultative anaerobe which, under conditions of oxygen depletion, uses Fe(III) as electron acceptor. A. hydrophila produces pili during growth with Fe(III). The study was focused on the characterization of the morphology, the electrical properties and the nature of the bacterial pili. Scanning electron microscopy and conductive-probe atomic force microscopy revealed the presence of filaments between cells and substrate and their conductive nature. Our results indicate that pili of A. hydrophila strain A might serve as biological nanowires, transferring electrons from the cell surface to the surface of Fe(III) oxides and, in addition, the possibility of playing a role in inter/intra species signaling. Quorum sensing (QS) is recognized as one of the main regulatory ways for extracellular polymeric substances (EPS) production and biofilm formation. We present evidence that nanowire formation can be regulated by addition of synthetic acyl-homoserine lactones (AHL). These conductive pili may be involved in various interactions, and their protein components might be usable in the future for biotechnological approaches in materials science.


Asunto(s)
Aeromonas hydrophila/fisiología , Conductividad Eléctrica , Microbiología Ambiental , Nanocables/microbiología , Acil-Butirolactonas/metabolismo , Aeromonas hydrophila/metabolismo , Aeromonas hydrophila/ultraestructura , Compuestos Férricos/metabolismo , Fimbrias Bacterianas/ultraestructura , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Percepción de Quorum
18.
Rev. chil. radiol ; 25(2): 47-49, jun. 2019. tab, graf, ilus
Artículo en Español | LILACS | ID: biblio-1013849

RESUMEN

Resumen: Introducción: El objetivo de este estudio fue desarrollar un modelo predictivo sobre la presencia de tuberculosis pulmonar activa utilizando datos clínico-epidemiológicos y hallazgos de radiografía simple (Rx) y tomografía computadorizada (TC) de tórax. Material y métodos: Se realizó un estudio observacional, retrospectivo, descriptivo y analítico, que recopiló 22 variables clínico-epidemiológicas, 11 hallazgos radiológicos en Rx de tórax y 23 en la TC, que se realizaron en pacientes con sospecha clínica de tuberculosis pulmonar durante un período de 10 años. Se aplicó un modelo de regresión logística multivariado a los predictores potenciales de cultivo positivo, obteniendo un modelo predictivo. Resultados: Se recogieron 1.540 pacientes con sospecha clínica de tuberculosis a los que se les realizó Rx y TC torácico. El cultivo fue positivo en 101 casos. Se utilizó un proceso de eliminación hacia atrás para obtener el mejor conjunto de variables predictivas. Se obtuvieron 24 variables que fueron significativas (6 clínicas, 5 de Rx y 13 de TC) y se les asignó una puntuación. A la suma de estas puntuaciones se restó la edad en años multiplicada por 0,03. El modelo sugiere el diagnóstico de tuberculosis pulmonar activa en pacientes con una puntuación superior a 1,845. Obtuvo una sensibilidad de 85,1%, especificidad de 83,6%, valor predictivo positivo de 26,6%, y valor predictivo negativo de 98,7%. El área bajo la curva ROC fue de 0,9163. Conclusión: Este sistema de puntuación basado en criterios clínico-epidemiológicos y hallazgos radiológicos puede ayudar a diagnosticar tuberculosis pulmonar activa en casos de sospecha diagnóstica.


Abstract:Introduction: The objective of this study was to develop a predictive model on the presence of active pulmonary tuberculosis using clinical-epidemiological data and findings of chest radiography and thoracic computed tomography (CT). Material and methods: An observational, retrospective, descriptive and analytical study was conducted, which collected 22 clinical and epidemiological variables, 11 radiological findings on chest x-ray and 23 on CT that were performed in patients with clinical suspicion of pulmonary tuberculosis during a period of 10 years. A multivariate logistic regression model was applied to the potential predictors of positive culture, obtaining a predictive model. Results: We collected 1,540 patients with clinical suspicion of tuberculosis who underwent radiography and thoracic CT. The culture was positive in 101 cases. A backward elimination process was used to obtain the best set of predictive variables. We obtained 24 variables that were significant (6 clinical, 5 of chest plain films and 13 of CT) and were assigned a score. The sum of these scores was subtracted from the age in years and multiplied by 0.03. The model suggests the diagnosis of active pulmonary tuberculosis in patients with a score higher than 1.845. The model obtained a sensitivity of 85.1%, specificity of 83.6%, positive predictive value of 26.6, and negative predictive value of 98.7%. The area under the ROC curve was 0.9163. Conclusion: This scoring system based on clinical-epidemiological criteria and radiological findings can help rule out active pulmonary tuberculosis in cases of diagnostic suspicion.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Tuberculosis Pulmonar/diagnóstico por imagen , Radiografía Torácica , Tomografía Computarizada por Rayos X , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/epidemiología , Modelos Logísticos , Epidemiología Descriptiva , Análisis Multivariante , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Curva ROC , Sensibilidad y Especificidad , Factores de Edad
19.
IET Nanobiotechnol ; 7(3): 109-16, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24028809

RESUMEN

The increasing demand and limited natural resources of noble metals make its recovery from dilute industrial wastes attractive, especially when using environmentally friendly methods. Nowadays, the high impact that nanotechnology is having in both science and society offers new research possibilities. Gold and silver nanoparticles were biosynthesised by a simple method using different algae as reducing agent. The authors explored the application of dead algae in an eco-friendly procedure. The nanoparticle formation was followed by UV-vis absorption spectroscopy and transmission electron microscopy. The functional groups involved in the bioreduction were studied by Fourier transform infrared spectroscopy.


Asunto(s)
Chondrus/metabolismo , Nanopartículas del Metal/química , Biomasa , Oro/química , Tecnología Química Verde , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Plata/química , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
20.
Methods Mol Biol ; 877: 247-63, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22610633

RESUMEN

The ability of plants to remove pollutants from the environment is currently used in a simple and low-cost cleaning technology known as phytoremediation. Unfortunately, little is known about the metabolic pathways involved in the transformation of xenobiotic compounds and the ability of certain plants to tolerate, detoxify, and store high concentrations of heavy metals. Plant cell and tissue culture is considered an important tool for fundamental studies that provide information about the plant-contaminant relationships, help to predict plant responses to environmental contaminants, and improve the design of plants with enhanced characteristics for phytoremediation. Callus, cell suspensions, hairy roots, and shoot multiplication cultures are used to study the interactions between plants and pollutants under aseptic conditions. Many plant species have an inherent ability to accumulate/metabolize a variety of pollutants, but they normally produce little biomass. However, fast-growing trees are excellent candidates for phytoremediation because of their rapid growth, extensive root system, and high water uptake. This chapter outlines the in vitro plant production of both somaclonal variants and transgenic plants of Populus spp. that exhibit high tolerance to heavy metals.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Metales Pesados/análisis , Populus/química , Populus/crecimiento & desarrollo , Técnicas de Cultivo de Tejidos , Biodegradación Ambiental , Contaminantes Ambientales/metabolismo , Metales Pesados/metabolismo
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