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1.
Biofouling ; 32(6): 657-69, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27192622

RESUMO

Microbial communities of natural subaerial biofilms developed on granitic historic buildings of a World Heritage Site (Santiago de Compostela, NW Spain) were characterized and cultured in liquid BG11 medium. Environmental barcoding through next-generation sequencing (Pacific Biosciences) revealed that the biofilms were mainly composed of species of Chlorophyta (green algae) and Ascomycota (fungi) commonly associated with rock substrata. Richness and diversity were higher for the fungal than for the algal assemblages and fungi showed higher heterogeneity among samples. Cultures derived from natural biofilms showed the establishment of stable microbial communities mainly composed of Chlorophyta and Cyanobacteria. Although most taxa found in these cultures were not common in the original biofilms, they are likely common pioneer colonizers of building stone surfaces, including granite. Stable phototrophic multi-species cultures of known microbial diversity were thus obtained and their reliability to emulate natural colonization on granite should be confirmed in further experiments.


Assuntos
Biofilmes/crescimento & desenvolvimento , Clorófitas/crescimento & desenvolvimento , Materiais de Construção/microbiologia , Cianobactérias/crescimento & desenvolvimento , Fungos/crescimento & desenvolvimento , Dióxido de Silício/química , Arquitetura/história , Biodiversidade , Clorófitas/classificação , Cianobactérias/classificação , Microbiologia Ambiental , Fungos/classificação , História Medieval , Processos Fototróficos , Reprodutibilidade dos Testes , Espanha , Propriedades de Superfície
2.
Actas Dermosifiliogr ; 107(4): 275-83, 2016 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26708562

RESUMO

Although the diversity of the clinical manifestations of syphilis is well-known, atypical presentations can also occur. Such atypical presentations are associated with a high risk of transmission as a result of diagnostic confusion and treatment delays owing to the disease's ability to mimic other common skin diseases, deviate from classic clinical presentations, and adopt unique forms. Cases of atypical syphilis have been described most frequently in patients with concomitant human immunodeficiency virus (HIV) infection. Because the incidence of syphilis has been growing over recent years -particularly in patients with HIV co-infection- dermatologists need to be familiar with the less well-known clinical presentations of this venereal disease.


Assuntos
Sífilis Cutânea/diagnóstico , Infecções por HIV/complicações , Humanos , Índice de Gravidade de Doença , Sífilis Cutânea/classificação , Sífilis Cutânea/complicações
3.
Andes Pediatr ; 94(2): 144-152, 2023 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-37358107

RESUMO

In Chile, between 450 and 500 cases of cancer are diagnosed annually in children and adolescents. Treatment is financed by the state, but there are non-financial elements that could condition adherence to treatment. OBJECTIVE: to explore family, socioeconomic, housing, and support network risk factors that could affect adherence to medical treatment in children and adolescents diagnosed with cancer. PATIENTS AND METHOD: Descriptive observational study in pediatric oncology hospitals of a national cancer program. Through a "Social Care Form" applied to 104 caregivers of children and adolescents, between August 2019 and March 2020, socioeconomic data of children diagnosed with cancer were recorded in four dimensions: i) Individual/family/health; ii) Work/education/socioeconomic; iii) Housing/environment; and iv) Participation/support networks. RESULTS: 99% of the children and adolescents were registered in the public health system; 69% belonged to the lowest income brackets. Care for children and adolescents was mainly provided by the mother (91%). 79% reported living in a house; 48% owned or were paying for their home. Housing quality was described as good (70%), with low levels of overcrowding. 56% of households had access to Wi-Fi internet connection, while 27% reported no access. The main support network reported was the family (84%). CONCLUSIONS: Family, socioeconomic, housing, and support network risk factors were observed in children and adolescents diagnosed with cancer; socioeconomic and gender aspects highlight the social inequalities in these families. Descriptive baseline results were obtained, so it is suggested to re-observe its evolution and thus measure its impact on adherence to treatment.


Assuntos
Neoplasias , Cooperação e Adesão ao Tratamento , Humanos , Criança , Adolescente , Neoplasias/psicologia , Neoplasias/terapia , Fatores Socioeconômicos , Apoio Social , Habitação
4.
Biofouling ; 28(3): 329-38, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22452392

RESUMO

This paper addresses the detection and monitoring of the development of epilithic phototrophic biofilms on the granite façade of an institutional building in Santiago de Compostela (NW Spain), and reports a case study of preventive conservation. The results provide a basis for establishing criteria for the early detection of phototrophic colonization (greening) and for monitoring its development on granite buildings by the use of color changes recorded with a portable spectrophotometer and represented in the CIELAB color space. The results show that parameter b* (associated with changes of yellowness-blueness) provides the earliest indication of colonization and varies most over time, so that it is most important in determining the total color change. The limit of perception of the greening on a granite surface was also established in a psycho-physical experiment, as Δb*: +0.59 CIELAB units that correspond, in the present study, to 6.3 µg of biomass dry weight cm(-2) and (8.43 ± 0.24) × 10(-3) µg of extracted chlorophyll a cm(-2).


Assuntos
Biofilmes/crescimento & desenvolvimento , Clorofila/metabolismo , Cor/normas , Materiais de Construção/microbiologia , Processos Fototróficos , Dióxido de Silício , Espectrofotometria/métodos , Incrustação Biológica/prevenção & controle , Clorofila A , Monitoramento Ambiental , Espanha
5.
Biodegradation ; 23(5): 705-16, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22367465

RESUMO

Nitrocellulose is one of the most commonly used compounds in ammunition and paint industries and its recalcitrance to degradation has a negative impact on human health and the environment. In this study the capability of Desulfovibrio desulfuricans ATCC 13541 to degrade nitrocellulose as binder in paint was assayed for the first time. Nitrocellulose-based paint degradation was followed by monitoring the variation in nitrate, nitrite and ammonium content in the culture medium using Ultraviolet-Visible spectroscopy. At the same time cell counts and ATP assay were performed to estimate bacterial density and activity in all samples. Infrared spectroscopy and colorimetric measurements of paint samples were performed to assess chemical and colour changes due to the microbial action. Microscope observations of nitrocellulose-based paint samples demonstrated the capability of the bacterium to adhere to the paint surface and change the paint adhesive characteristics. Finally, preliminary studies of nitrocellulose degradation pathway were conducted by assaying nitrate- and nitrite reductases activity in D. desulfuricans grown in presence or in absence of paint. We found that D. desulfuricans ATCC 13541 is able to transform nitrocellulose as paint binder and we hypothesised ammonification as degradation pathway. The results suggest that D. desulfuricans ATCC 13541 is a good candidate as a nitrocellulose-degrading bacterium.


Assuntos
Colódio/metabolismo , Desulfovibrio desulfuricans/metabolismo , Pintura , Biodegradação Ambiental , Cor , Desulfovibrio desulfuricans/citologia , Desulfovibrio desulfuricans/enzimologia , Humanos , Microscopia de Fluorescência , Nitrato Redutase/metabolismo , Nitrito Redutases/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Especificidade por Substrato
6.
J Assist Reprod Genet ; 29(10): 1067-71, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22815004

RESUMO

PURPOSE: The aim of our study was to ascertain the influence of hCG levels at oocyte pick-up on IVF outcomes, and their relationship with clinical parameters. METHODS: A prospective study was performed including 473 women undergoing IVF, aged under 40 years. Blood samples to analyze hCG levels were obtained at the time of follicular aspiration, 36 h after the administration of 250 µg of recombinant hCG. RESULTS: Neither the numbers of oocytes obtained or fertilized, nor the pregnancy rate, were correlated with hCG levels. Moreover, hCG values were very similar in women who did and did not become pregnant (123.3 ± 48.7 and 117.5 ± 44.7 mUI/mL). Cases in which no oocytes were recovered after follicular aspiration had similar hCG levels to those in which more than 1 oocyte was obtained. On the other hand, hCG levels were negatively related to body mass index, weight, and age. CONCLUSIONS: These data indicate that after the administration of 250 µg of recombinant hCG, hCG levels are not responsible for failure to recover oocytes. Specifically, there was no correlation between plasma hCG levels and the number of oocytes obtained or other markers of IVF outcome. There was, however, an inverse relationship with BMI, body weight and age.


Assuntos
Gonadotropina Coriônica/sangue , Gonadotropina Coriônica/uso terapêutico , Fertilização in vitro , Recuperação de Oócitos , Proteínas Recombinantes/uso terapêutico , Adulto , Fatores Etários , Índice de Massa Corporal , Gonadotropina Coriônica/farmacologia , Feminino , Humanos , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Proteínas Recombinantes/farmacologia , Resultado do Tratamento
7.
eNeuro ; 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35584913

RESUMO

Brain aging is a natural process that involves structural and functional changes that lead to cognitive decline, even in healthy subjects. This detriment has been associated with N-methyl-D-aspartate receptor (NMDAR) hypofunction due to a reduction in the brain levels of D-serine, the endogenous NMDAR co-agonist. However, it is not clear if D-serine supplementation could be used as an intervention to reduce or reverse age-related brain alterations. In the present work, we aimed to analyze the D-serine effect on aging-associated alterations in cellular and large-scale brain systems that could support cognitive flexibility in rats. We found that D-serine supplementation reverts the age-related decline in cognitive flexibility, frontal dendritic spine density, and partially restored large-scale functional connectivity without inducing nephrotoxicity; instead, D-serine restored the thickness of the renal epithelial cells that were affected by age. Our results suggest that D-serine could be used as a therapeutic target to reverse age-related brain alterations.SIGNIFICANT STATEMENTAge-related behavioral changes in cognitive performance occur as a physiological process of aging. Then, it is important to explore possible therapeutics to decrease, retard or reverse aging effects on the brain. NMDA receptor hypofunction contributes to the aging-associated cognitive decline. In the aged brain, there is a reduction in the brain levels of the NMDAR co-agonist, D-Serine. However, it is unclear if chronic D-serine supplementation could revert the age-detriment in brain functions. Our results show that D-serine supplementation reverts the age-associated decrease in cognitive flexibility, functional brain connectivity, and neuronal morphology. Our findings raise the possibility that restoring the brain levels of D-serine could be used as a therapeutic target to recover brain alterations associated with aging.

8.
Reprod Biomed Online ; 22 Suppl 1: S43-51, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21575849

RESUMO

This single-centre, randomized, parallel group, comparative study aimed to identify potential benefits of mid-follicular recombinant human LH (r-HLH) supplementation in women aged 35-39 years undergoing ovarian stimulation for intracytoplasmic sperm injection (ICSI). The main endpoint was the number of metaphase II oocytes retrieved. After pituitary suppression with a gonadotrophin-releasing hormone agonist, ovarian stimulation was initiated with recombinant human FSH (r-HFSH; 300-450 IU/day). On stimulation day 6, patients were randomized to receive r-HFSH alone or r-HFSH + r-HLH (r-HLH 150 IU/day) for the remainder of the stimulation period. Final follicular maturation was triggered with 250 µg of recombinant human chorionic gonadotrophin. After assessing oocyte nuclear maturity, oocyte were fertilized by ICSI and afterwards embryo quality was analyzed. Of the 131 women enrolled, 68 were allocated to r-HFSH alone and 63 to r-HFSH + r-HLH. No significant differences were observed in markers of either oocyte or embryo quality or quantity. However, higher rates of implantation and live birth per started cycle were observed with r-HLH supplementation than with r-HFSH alone. Although additional large studies are required to further investigate these findings, r-HLH supplementation for women aged 35-39 years undergoing ICSI is recommended as it may have a beneficial action on implantation.

9.
J Ind Microbiol Biotechnol ; 38(1): 179-88, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20820857

RESUMO

Biological colonization of rock surfaces constitutes an important problem for maintenance of buildings and monuments. In this work, we aim to establish an efficient extraction protocol for chlorophyll-a specific for rock materials, as this is one of the most commonly used biomarkers for quantifying phototrophic biomass. For this purpose, rock samples were cut into blocks, and three different mechanical treatments were tested, prior to extraction in dimethyl sulfoxide (DMSO). To evaluate the influence of the experimental factors (1) extractant-to-sample ratio, (2) temperature, and (3) time of incubation, on chlorophyll-a recovery (response variable), incomplete factorial designs of experiments were followed. Temperature of incubation was the most relevant variable for chlorophyll-a extraction. The experimental data obtained were analyzed following a response surface methodology, which allowed the development of empirical models describing the interrelationship between the considered response and experimental variables. The optimal extraction conditions for chlorophyll-a were estimated, and the expected yields were calculated. Based on these results, we propose a method involving application of ultrasound directly to intact sample, followed by incubation in 0.43 ml DMSO/cm(2) sample at 63°C for 40 min. Confirmation experiments were performed at the predicted optimal conditions, allowing chlorophyll-a recovery of 84.4 ± 11.6% (90% was expected), which implies a substantial improvement with respect to the expected recovery using previous methods (68%). This method will enable detection of small amounts of photosynthetic microorganisms and quantification of the extent of biocolonization of stone surfaces.


Assuntos
Biomassa , Clorofila/isolamento & purificação , Materiais de Construção/microbiologia , Temperatura , Biofilmes , Biomarcadores/análise , Clorofila A , Cianobactérias/química , Cianobactérias/crescimento & desenvolvimento , Dimetil Sulfóxido/química , Modelos Químicos , Processos Fototróficos , Fatores de Tempo , Ultrassom
10.
Biodegradation ; 22(4): 763-71, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20714920

RESUMO

The application of biocides is a traditional method of controlling biodecay of outdoor cultural heritage. Chlorophyll degradation to phaeopigments is used to test the biocidal efficacy of the antimicrobial agents. In the present study, the usefulness of color measurements in estimating chlorophyll degradation was investigated. An aeroterrestrial stone biofilm-forming cyanobacterium of the genus Nostoc was chosen as test organism, comparing its different behaviour in both planktonic and biofilm mode of growth against the isothiazoline biocide Biotin T®. Changes in A(435 nm)/A(415 nm) and A(665 nm)/A(665a nm) and in the chlorophyll a and adenosine triphosphate (ATP) cell content were compared with the variations in the CIELAB color parameters (L*, a*, b*, C*(ab) and h(ab)). Our findings showed that both the phaeophytination indexes are useful in describing degradation of chlorophyl a to phaeopigments. Moreover, the CIELAB color parameters represented an effective tool in describing chlorophyll degradation. L* CIELAB parameter appeared to be the most informative parameter in describing the biocidal activity of Biotin T® against Nostoc sp. in both planktonic and biofilm mode of growth.


Assuntos
Biodegradação Ambiental/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Clorofila/antagonistas & inibidores , Colorimetria/métodos , Nostoc/efeitos dos fármacos , Feofitinas/análise , Plâncton/efeitos dos fármacos , Tiazóis/farmacologia , Trifosfato de Adenosina/metabolismo , Biofilmes/crescimento & desenvolvimento , Clorofila/química , Clorofila/metabolismo , Clorofila A , Cor , Desinfetantes/farmacologia , Magnésio/metabolismo , Microscopia , Nostoc/metabolismo , Feofitinas/química , Plâncton/crescimento & desenvolvimento , Espectrofotometria
11.
Sci Total Environ ; 770: 145314, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33736404

RESUMO

2020 marks 25 years since Olivier Guillitte defined the term 'bioreceptivity', to describe the ability of a building material to be colonised by living organisms. Although Guillitte noted in his 1995 paper that several issues required further investigation, to the best of our knowledge the bioreceptivity concept has not been restated, reviewed, reanalysed or updated since then. The present paper provides an opinionated exposition of the status and utility of the bioreceptivity concept for built heritage science and conservation in the light of current knowledge, aimed to stimulate further discussion. A bibliometric analysis highlights the key dimensions of the past 25 years of published research, showing that the term bioreceptivity has been widely used in the field of built cultural heritage. In our reanalysis of the concept, special attention is devoted to the six types of bioreceptivity (primary, secondary, tertiary, intrinsic, extrinsic and semi-extrinsic) articulated by Guillitte in 1995. We propose that field-based studies of bioreceptivity are urgently needed, and that the intrinsic, extrinsic and semi-extrinsic types of bioreceptivity should be dropped, and a new category (quaternary bioreceptivity) added. Additionally, we propose that bioreceptivity in submerged and subsoil environments should also be considered. Bioreceptivity remains an important concept for managing both new build and built heritage, as it provides the key to understanding the drivers and patterns of biological colonisation of building materials.


Assuntos
Materiais de Construção
12.
Biofouling ; 26(5): 499-509, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20425659

RESUMO

Previous studies have provided evidence that color measurements enable on site quantification of superficial biofilms, thereby avoiding the need for sampling. In the present study, the efficiency of color measurements to evaluate to what extent pigment production is affected by environmental parameters such as light intensity, combined nitrogen and nutrient availability, was tested with two cyanobacteria, Nostoc sp. strains PCC 9104 and PCC 9025, which form biofilms on stone. Both strains were acclimated, in aerated batch cultures for 2 weeks, to three different culture media: BG-11, BG-11(0), and BG-11(0)/10 at either high or low light intensity. The content of chlorophyll a, carotenoids, and phycocyanins was measured throughout the experiment, together with variations in the color of the cyanobacteria, which were represented in the CIELAB color space. The results confirmed that the CIELAB color parameters are correlated with pigment content in such a way that variations in the latter are reflected as variations in color.


Assuntos
Cianobactérias/genética , Cianobactérias/metabolismo , Luz , Nitrogênio/metabolismo , Nostoc/metabolismo , Biofilmes , Carotenoides/genética , Clorofila , Clorofila A , Cor , Nostoc/genética , Fenciclidina/análogos & derivados , Feocromocitoma/genética , Ficocianina/genética , Proteínas/genética
13.
Rev Esp Sanid Penit ; 22(1): 23-31, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32406478

RESUMO

OBJECTIVES: To examine the predictive validity of the HCR-20 (The Historical Clinical Risk Management-20) to predict future violent incidents in a representative sample of patients with severe mental disorders and with a history of previous admission to prison, who after release are in a situation of extreme social exclusion. MATERIAL AND METHOD: The study sample was selected from the 235 patients treated by the Mental Health Street Team of Madrid (ECASAM) from June 2014 to June 2017, including those with a previous history of a previous internment in a penitentiary (about which, the HCR-20 was completed). RESULTS: Of the 44 patients included, 29.6% (n=13) ended up participating in a violent incident after the release. The ROC curves (Receiver Operating Characteristic) analysis indicated that the total score of HCR-20 (AUC 0.98, p=0.01) has a high predictive validity. CONCLUSIONS: The social and medical changes that take place after the release of patients with severe mental illness justify the need to reassess the risk of violence. In this evaluation, the HCR-20 guide is a useful tool for predicting the risk of involvement in future violent incidents, and the inclusion of factors such as social exclusion and its consequences, as well as problems with substance use is especially important.


Assuntos
Criminosos/psicologia , Pessoas Mal Alojadas/psicologia , Transtornos Mentais/psicologia , Testes Psicológicos , Reincidência/psicologia , Isolamento Social/psicologia , Violência/psicologia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prisioneiros/psicologia , Curva ROC , Estudos Retrospectivos , Medição de Risco , Gestão de Riscos , Marginalização Social/psicologia , Violência/prevenção & controle
14.
Hum Reprod ; 24(4): 954-65, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19095664

RESUMO

BACKGROUND: The development of non-invasive diagnostic methods for endometriosis requires sensitive and disease specific biomarkers. Here, we describe the use of aspirated endometrial fluid from women with and without endometriosis as a novel biological sample for biomarker discovery. METHODS: Differential protein expression profiling of aspirates from women with early endometriosis (n = 14), advanced endometriosis (n = 32) and without evidence of the disease (n = 32) was assessed by two-dimensional gel electrophoresis (2-DE). A biomarker validation study was performed in an independent cohort (early endometriosis n = 6 and advanced endometriosis n = 14, controls n = 15). RESULTS: The analysis resulted in the identification of 31 proteins showing statistically significant differences in expression. The proteins identified are related to cell signalling, cell death and cell movement, processes that may be involved in the onset and/or progression of endometriosis. The differences in expression observed for 14-3-3 (signal transduction) and moesin (cytoskeletal structure) were confirmed in an independent group of endometriosis patients. CONCLUSIONS: Endometrial fluid represents a novel sample for proteomic analysis offering reliable, disease specific information on protein expression, facilitating the discovery of biomarkers for endometriosis. The results described here complement previous proteomic studies, providing new endometriosis-related proteins to be validated as diagnostic markers.


Assuntos
Biomarcadores/metabolismo , Líquidos Corporais/metabolismo , Endometriose/diagnóstico , Endometriose/metabolismo , Endométrio/metabolismo , Proteínas/metabolismo , Adolescente , Adulto , Western Blotting , Estudos de Casos e Controles , Eletroforese em Gel Bidimensional , Feminino , Humanos , Pessoa de Meia-Idade , Análise Serial de Proteínas , Proteínas/isolamento & purificação , Proteômica , Sensibilidade e Especificidade , Adulto Jovem
15.
Reprod Biomed Online ; 19(6): 879-87, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20031032

RESUMO

This single-centre, randomized, parallel group, comparative study aimed to identify potential benefits of mid-follicular recombinant human LH (r-HLH) supplementation in women aged 35-39 years undergoing ovarian stimulation for intracytoplasmic sperm injection (ICSI). The main endpoint was the number of metaphase II oocytes retrieved. After pituitary suppression with a gonadotrophin-releasing hormone agonist, ovarian stimulation was initiated with recombinant human FSH (r-HFSH; 300-450 IU/day). On stimulation day 6, patients were randomized to receive r-HFSH alone or r-HFSH + r-HLH (r-HLH 150 IU/day) for the remainder of the stimulation period. Final follicular maturation was triggered with 250 mug of recombinant human chorionic gonadotrophin. After assessing oocyte nuclear maturity, oocyte were fertilized by ICSI and afterwards embryo quality was analyzed. Of the 131 women enrolled, 68 were allocated to r-HFSH alone and 63 to r-HFSH + r-HLH. No significant differences were observed in markers of either oocyte or embryo quality or quantity. However, higher rates of implantation and live birth per started cycle were observed with r-HLH supplementation than with r-HFSH alone. Although additional large studies are required to further investigate these findings, r-HLH supplementation for women aged 35-39 years undergoing ICSI is recommended as it may have a beneficial action on implantation.


Assuntos
Hormônio Foliculoestimulante Humano/administração & dosagem , Hormônio Luteinizante/administração & dosagem , Folículo Ovariano/fisiologia , Indução da Ovulação/métodos , Adulto , Implantação do Embrião/efeitos dos fármacos , Feminino , Fase Folicular , Humanos , Recuperação de Oócitos/métodos , Folículo Ovariano/efeitos dos fármacos , Gravidez , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas
16.
Bioresour Technol ; 99(8): 2887-92, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17689244

RESUMO

The present study was undertaken to investigate the viability of the use of two waste products, cheese whey and composted organic waste, as nutrient sources in the induction of biological films on quartz surfaces, with the final aim of reducing the visual impact generated by quartz mining. Experiments were carried in laboratory in which quartz samples were colonized with microorganisms (mainly cyanobacteria) forming biofilms. Previous studies have shown that a nutritional supplement must be added for good development of biofilms and, therefore, application of the two waste products was compared with application of the chemical nutrient medium on which these types of microorganisms are usually cultivated. Both products provided better results than the culture medium, in terms of the speed of formation of the biofilm, faster with the waste products, and the degree of cover of the brilliant white colour of the quartz, better masked by the biofilms formed when the waste products were applied as a darker biofilm was obtained.


Assuntos
Biodegradação Ambiental , Biofilmes , Conservação dos Recursos Naturais/métodos , Mineração , Quartzo , Resíduos/análise , Metais/isolamento & purificação , Quartzo/química , Quartzo/isolamento & purificação
17.
Sci Total Environ ; 633: 112-121, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29573678

RESUMO

Bioreceptivity is a fundamental concept in the ornamental stone industry and in the fields of cultural heritage and civil engineering to understand the susceptibility of stone constructions to biological colonisation and subsequent biodeterioration. However, a bioreceptivity index (BI) has not yet been established for any construction material. The aim of the present study is developing a simple, robust and well-founded BI for granitic rocks. For this purpose, a standardised laboratory protocol was used to grow phototrophic biofilms on several varieties of granite. The colonisation was then assessed by chlorophyll fluorescence and colour measurements. Based on the results thus obtained, a BI including two components (BIgrowth and BIcolour) is proposed. BIgrowth quantifies the extent of the biological growth and BIcolour quantifies the colour change undergone by the stone due to the colonisation, which can be considered the bioreceptivity perceptible to the human eye. The values of BI, BIgrowth and BIcolour were fitted to a scale of 0-10, thus enabling qualitative classification of the lithotypes according to their primary bioreceptivity. Eleven varieties of granite commonly used as construction material and with a honed surface finish (one variety with three additional surface finishes: polished, sawn and sanded) were thus assigned the corresponding BI, which represents a new quality factor for the stone industry. The index can therefore be used by end-users as a decision-making tool in the selection of appropriate lithotypes for building and/or ornamental purposes.

18.
J Chromatogr A ; 1147(1): 79-84, 2007 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-17320890

RESUMO

The formation of dark patinas has been mainly related with deposition of gases and particles, and sulphation mechanisms particularly in calcareous rocks. However, in granitic monuments located in Galicia (northwest of Spain), especially in rural areas, this origin is unlikely since granite is a very poor calcium-containing rock and the atmospheric pollution in this area is negligible. A biological origin seems to be most probable. In order to know the importance of biological and atmospheric factors in the formation of dark patinas on granitic monuments, a number of analyses using several techniques are needed. The characterization of fatty acids in patinas by gas chromatography has established clear differences among samples. Thus, all of the samples having a biological origin displayed a similar fatty acid pattern, with unsaturated fatty acids predominating, especially oleic and linoleic acids; these were followed in abundance by the branched fatty acid 18:00 anteiso, and palmitic acid. Different patterns of fatty acid allowed establishment of an anthropogenic origin of the some of the patinas analysed.


Assuntos
Cromatografia Gasosa/métodos , Materiais de Construção/análise , Cultura , Ácidos Graxos não Esterificados/análise , Ácidos Graxos Insaturados/análise , Teste de Materiais , Dióxido de Silício/química , Arte , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Ácidos Linoleicos , Ácidos Oleicos , Ácido Palmítico , Espanha , Propriedades de Superfície
19.
Ann Clin Biochem ; 44(Pt 2): 182-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17362585

RESUMO

BACKGROUND: Transplantation is the main palliative treatment for patients with heart failure. Clinical signs of cardiac rejection can be very non-specific or even absent. Thus, successful management relies on early diagnosis, ideally before the onset of clinical features of cardiac dysfunction. Although endomyocardial biopsy (EMB) is the reference diagnostic method, several non-invasive methods have been proposed to reduce the number of EMB performed during the follow-up of the transplanted patient. The aim of the present work was to study the potential relationship between rejection and serum concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) as well as cardiac troponin T (cTnT) in post-transplantation patients. METHODS: Twenty-three consecutive orthotopic heart transplantation recipients with a mean age of 51 years (range 22-66) were prospectively recruited from the cardiac transplantation programme at the Hospital Universitario Central de Asturias. Serum NT-proBNP and cTnT were measured during the follow-up of these patients (ranging from 9-13 months post-transplantation) and compared with the results of EMB. RESULTS: Serum NT-proBNP concentrations progressively decrease during the first year post-transplantation, reaching concentrations slightly higher than the reference values. NT-proBNP concentrations increase significantly in those patients with a rejection episode graded >or=3A on the basis of the EMB (P<0.001, Mann-Whitney U-test). No relation between cTnT and rejection was observed. CONCLUSIONS: The potential of NT-proBNP as a non-invasive marker of transplantation rejection shows promising results, since NT-proBNP concentrations increase whenever a significant rejection event takes place in the first year of follow-up.


Assuntos
Biomarcadores/sangue , Rejeição de Enxerto/sangue , Transplante de Coração , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Adulto , Idoso , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/prevenção & controle , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade
20.
Sci Total Environ ; 381(1-3): 280-9, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17499341

RESUMO

Formation of dark patinas on rocky surfaces is mainly related to the deposition of gases and particles and to sulphation mechanisms. In the present study, samples of dark patinas taken from granitic outcrops and from granitic buildings were examined in an attempt to understand the mechanisms of their formation. The outcrops are located in non-polluted areas and are characterized by the absence of any extraneous material that provides calcium, such as e.g. mortar. The buildings are located in areas with low levels of pollution. The climate in the study area favours proliferation of microorganisms. Important differences between the patinas sampled from outcrops and from buildings were observed, as the former are of biological origin and the latter of anthropogenic origin. Although the levels of pollution are low in the sampling area, sulphur was present in all of the samples from urban buildings. Sulphur was not present in patinas from outcrops or in patinas from monuments that are assumed to behave as outcrops (dolmens), although the latter are also of anthropogenic origin. Finally, the patinas were found to be formed by elements accumulated on the surface and not from elements contained within the rock itself.


Assuntos
Dióxido de Silício/química , Biofilmes/crescimento & desenvolvimento , Carbono/análise , Clorofila/análise , Clorofila A , Cor , Hidrogênio/análise , Nitrogênio/análise , Proteínas/análise , Enxofre/análise
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