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1.
J Fungi (Basel) ; 9(4)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37108954

RESUMO

In this study, we explored the biodiversity and abundance of culturable fungi in four samples associated with different biodeterioration outlines collected from the Lemos Pantheon, a limestone-built artwork in Portugal. We compared the results from prolonged standard freezing with those previously obtained from fresh samples to analyze differences in the obtained community and assess the effectiveness of the standard freezing incubation protocol in uncovering a different segment of culturable fungal diversity. Our results showed a slight decrease in culturable diversity, but over 70% of the obtained isolates were not present in the previously studied fresh samples. We also identified a high number of potential new species with this procedure. Moreover, the use of a wide variety of selective culture media positively influenced the diversity of the cultivable fungi obtained in this study. These findings highlight the importance of developing new protocols under varying conditions to accurately characterize the culturable fraction in a given sample. The identification and study of these communities and their possible contribution to the biodeterioration process is crucial knowledge for formulating effective conservation and restoration plans to prevent further damage to valuable cultural heritage assets.

2.
J Fungi (Basel) ; 9(9)2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37755024

RESUMO

With an impressive ability to survive in harsh environments, black fungi are an ecological group of melanized fungi that are widely recognized as a major contributor to the biodeterioration of stone cultural heritage materials. As part of the ongoing efforts to study the fungal diversity thriving in a deteriorated limestone funerary art piece at the Lemos Pantheon, a national monument located in Águeda, Portugal, two isolates of an unknown microcolonial black fungus were retrieved. These isolates were thoroughly studied through a comprehensive analysis based on a multi-locus phylogeny of a combined dataset of ITS rDNA, LSU, and rpb2, along with morphological, physiological, and ecological characteristics. Based on the data obtained from this integrative analysis, we propose a new genus, Saxispiralis gen. nov., and a new species, Saxispiralis lemnorum sp. nov., in the recently described Aeminiaceae family (order Mycosphaerellales). Prior to this discovery, this family only had one known genus and species, Aeminium ludgeri, also isolated from deteriorated limestone. Additionally, considering the isolation source of the fungus and to better understand its potential contribution to the overall stone monument biodeterioration, its in vitro biodeteriorative potential was also evaluated. This work represents a significant contribution to the understanding of the fungal diversity involved in the biodeterioration of limestone heritage.

3.
Microorganisms ; 9(4)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808176

RESUMO

The "University of Coimbra-Alta and Sofia" area was awarded the UNESCO World Heritage Site distinction in 2013. The Old Cathedral of Coimbra, a 12th-century limestone monument located in this area, has been significantly impacted during the last 800 years by physical, chemical, and biological processes. This led to the significant deterioration of some of its structures and carvings, with loss of aesthetical, cultural, and historical values. For this work, deteriorated spots of the walls of three semi-open chapels from the cloister of the Cathedral were sampled to ascertain their bacterial and archaeal structural diversity. Based on Next-Generation Sequencing (NGS) result analysis, we report the presence of microbial populations that are well adapted to an ecosystem with harsh conditions and that can establish a diverse biofilm in most cases. While it was possible to determine dominant phylogenetic groups in Archaea and Bacteria domains, there was no clear connection between specific core microbiomes and the different deterioration patterns analyzed. The distribution of these archaeal and bacterial communities within the analyzed biodeterioration spots suggests they are more influenced by abiotic factors (i.e., water availability, salinity, etc.), although they influence (and are influenced by) the algal and fungal population composition in this ecosystem. This work provides valuable information that can assist in establishing future guidelines for the preservation and conservation of this kind of historic stone monuments.

4.
Microbiol Resour Announc ; 9(26)2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32586873

RESUMO

The recently described species Myxacorys almedinensis and two other cyanobacteria were isolated from the limestone walls of the Old Cathedral of Coimbra, Portugal (UNESCO World Heritage Site). The high-quality genome sequences presented here will be essential for characterization purposes and description of the novel taxa.

5.
MycoKeys ; (45): 57-73, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30728746

RESUMO

When colonizing stone monuments, microcolonial black fungi are considered one of the most severe and resistant groups of biodeteriorating organisms, posing a very difficult challenge to conservators and biologists working with cultural heritage preservation. During an experimental survey aimed to isolate fungi from a biodeteriorated limestone art piece in the Old Cathedral of Coimbra, Portugal (a UNESCO World Heritage Site), an unknown microcolonial black fungus was retrieved. The isolated fungus was studied through a complete examination based on multilocus phylogeny of a combined dataset of ITS rDNA, LSU and rpb2, in conjunction with morphological, physiological, and ecological characteristics. This integrative analysis allows for the description of a new family, Aeminiaceae fam. nov., a new genus Aeminium gen. nov., and a new species, Aeminiumludgeri sp. nov., in the order Capnodiales.

6.
Microbiol Resour Announc ; 8(14)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30948467

RESUMO

Aeminium ludgeri is an extremotolerant microcolonial black fungus isolated from a biodeteriorated limestone art piece in the Old Cathedral of Coimbra, Portugal (a UNESCO World Heritage Site). The high-quality draft genome sequence of Aeminium ludgeri presented here represents the first sequenced genome for both the recently described fungal family Aeminiaceae and the genus Aeminium.

7.
World J Gastroenterol ; 18(6): 551-6, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22363122

RESUMO

AIM: To describe a modified technique for placement of a tracheobronchial self-expanding plastic stent (SEPS) in patients with benign refractory hypopharyngeal strictures in order to improve dysphagia and allow stricture remodeling. METHODS: A case series of four consecutive patients with complex hypopharyngeal strictures after combined therapy for laryngeal cancer, previously submitted to multiple sessions of dilation without lasting improvement, is presented. All patients underwent placement of a small diameter and unflared tracheobronchial SEPS. Main outcome measurements were improvement of dysphagia and avoiding of repeated dilation. RESULTS: The modified introducer system allowed an easy and technically successful deployment of the tracheobronchial Polyflex stent through the stricture. All four patients developed complications related to stent placement. Two patients had stent migration (one proximal and one distal), two patients developed phanryngocutaneous fistulas and all patients with stents in situ for more than 8 wk had hyperplastic tissue growth at the upper end of the stent. Stricture recurrence was observed at 4 wk follow-up after stent removal in all patients. CONCLUSION: Although technically feasible, placement of a tracheobronchial SEPS is associated with a high risk of complications. Small diameter stents must be kept in place for longer than 3 mo to allow adequate time for stricture remodeling.


Assuntos
Constrição Patológica/cirurgia , Hipofaringe/patologia , Hipofaringe/cirurgia , Stents , Adulto , Idoso , Constrição Patológica/complicações , Constrição Patológica/patologia , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/cirurgia , Humanos , Neoplasias Laríngeas/terapia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
8.
Gastrointest Endosc ; 57(4): 498-504, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12665759

RESUMO

BACKGROUND: The aim of this study was to define the reproducibility and accuracy of magnification chromoendoscopy for the diagnosis of lesions associated with gastric cancer (intestinal metaplasia and dysplasia). METHODS: A total of 136 patients with previously diagnosed lesions and 5 gastrectomy specimens were studied. Endoscopic examination was performed with a magnification endoscope after methylene blue (1%) spraying. According to differences in color and mucosal pattern, groups and subgroups of endoscopic images were defined, and biopsies taken (n = 462). Five endoscopists were asked to classify individually 2 endoscopic images per subgroup on 2 separate occasions. RESULTS: Three groups of endoscopic images were defined: nonmetaplastic, nondysplastic mucosa (I); metaplastic mucosa (II); and dysplastic mucosa (III). Ten subgroups were defined according to pit pattern: round small (IA), round and tubular small (IB), coarse round (IC), and course round pits with a straight pit (ID); blue irregular marks (IIA), blue round and tubular pits (IIB), blue villi (IIC), and blue small pits (IID); and loss of clear pattern, with depression (IIIA) or with slight elevation (IIIB). The kappa statistic for intraobserver agreement on the classification of endoscopic images in groups was 0.86; for interobserver agreement, it was 0.74. For classification into subgroups, kappa values ranged from 0.48 to 0.78. For 85% of the areas classified endoscopically as Group I (n = 146), no mucosal lesions or gastritis was described at histologic examination; for 83% of those in Group II (n = 198), intestinal metaplasia was found. Subgroups IIA and IIB were more often associated with complete intestinal metaplasia (62%), and IIC and IID with incomplete metaplasia (67%); in Group III (n = 118), dysplasia was diagnosed histopathologically in 33%. For the diagnosis of dysplasia, specificity was 81% (95% CI [77%, 85%]) and negative predictive value 99% (95% CI [99%, 100%]). CONCLUSIONS: Gastric endoscopic patterns with chromoendoscopy and magnification seem reproducible and valid for the diagnosis of lesions associated with gastric cancer. This procedure may improve the follow-up of individuals at high-risk of gastric cancer, at least for the exclusion of severe lesions.


Assuntos
Endoscopia Gastrointestinal/métodos , Lesões Pré-Cancerosas/diagnóstico , Neoplasias Gástricas/diagnóstico , Cor , Humanos , Metaplasia , Variações Dependentes do Observador , Lesões Pré-Cancerosas/patologia , Reprodutibilidade dos Testes , Neoplasias Gástricas/patologia
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