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Until recently, microbiologists have relied on cultures to understand the microbial world. As a result, model organisms have been the focus of research into understanding Bacteria and Archaea at a molecular level. Diversity surveys and metagenomic sequencing have revealed that these model species are often present in low abundance in the environment; instead, there are microbial taxa that are cosmopolitan in nature. Due to the numerical dominance of these microorganisms and the size of their habitats, these lineages comprise mind-boggling population sizes upward of 1028 cells on the planet. Many of these dominant groups have cultured representatives and have been shown to be involved in mediating key processes in nature. Given their importance and the increasing need to understand changes due to climate change, we propose that members of Nitrosophaerota (Nitrosopumilus maritimus), SAR11 (Pelagibacter ubique), Hadesarchaeia, Bathyarchaeia, and others become models in the future. Abundance should not be the only measure of a good model system; there are other organisms that are well suited to advance our understanding of ecology and evolution. For example, the most well-studied symbiotic bacteria, like Buchnera, Aliivibrio, and Rhizobium, should be models for understanding host-associations. Also, there are organisms that hold new insights into major transitions in the evolution of life on the planet like the Asgard Archaea (Heimdallarchaeia). Innovations in a variety of in situ techniques have enabled us to circumvent culturing when studying everything from genetics to physiology. Our deepest understanding of microbiology and its impact on the planet will come from studying these microbes in nature. Laboratory-based studies must be grounded in nature, not the other way around.
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Dozens of new antiviral systems have been recently characterized in bacteria. Some of these systems are present in eukaryotes and appear to have originated in prokaryotes, but little is known about these defense mechanisms in archaea. Here, we explore the diversity and distribution of defense systems in archaea and identify 2610 complete systems in Asgardarchaeota, a group of archaea related to eukaryotes. The Asgard defense systems comprise 89 unique systems, including argonaute, NLR, Mokosh, viperin, Lassamu, and CBASS. Asgard viperin and argonaute proteins have structural homology to eukaryotic proteins, and phylogenetic analyses suggest that eukaryotic viperin proteins were derived from Asgard viperins. We show that Asgard viperins display anti-phage activity when heterologously expressed in bacteria. Eukaryotic and bacterial argonaute proteins appear to have originated in Asgardarchaeota, and Asgard argonaute proteins have argonaute-PIWI domains, key components of eukaryotic RNA interference systems. Our results support that Asgardarchaeota played important roles in the origin of antiviral defense systems in eukaryotes.
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Archaea , Proteínas Arqueais , Filogenia , Archaea/genética , Archaea/imunologia , Archaea/virologia , Proteínas Arqueais/metabolismo , Proteínas Arqueais/genética , Proteínas Argonautas/metabolismo , Proteínas Argonautas/genética , Eucariotos/genética , Eucariotos/imunologia , Bacteriófagos/genética , Bacteriófagos/fisiologia , Evolução MolecularRESUMO
INTRODUCTION: Discussions about the optimal lymph node (LN) count and its therapeutic consequences have persisted over time. The final LN count in colorectal tissues is affected by a variety of variables (patient, tumor, operation, pathologist, immune response). Methylene blue (MB) intra-arterial injection is a simple and inexpensive procedure that can be used to enhance lymph node count. AIM: Analyze whether there is a statistically significant difference between intra-arterial methylene blue injection and conventional dissection for the quantification of lymph nodes and determine if there is a variation in the quality of lymph node acquisition. METHODS AND RESULTS: Between 2015 and 2022, we conducted a retrospective analysis of colon cancer specimens. Data on the tumor's features, the number of lymph nodes, the number of lymph nodes that were positive, and other factors had been collected. The number of identified lymph nodes was highly significantly improved in the study group (P < 0.05). There is not a significant statistical difference between groups regarding the metastatic lymph node harvest. The group with injection of intra-arterial methylene blue shows a significantly decreased (P < 0.05) of the of cases with less than 12 lymph nodes recovered comparing with the control group. CONCLUSION: Colon cancer specimens can be easily evaluated concerning lymph nodes using the methylene blue method. Therefore, we strongly advise this approach as a standard procedure in the histological evaluation of colon cancer specimens in order to maximize the identification of lymph nodes. However, the detection of metastatic lymph nodes was unaffected significantly.
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Neoplasias do Colo , Azul de Metileno , Humanos , Azul de Metileno/administração & dosagem , Neoplasias do Colo/patologia , Neoplasias do Colo/tratamento farmacológico , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Linfonodos/patologia , Metástase Linfática , Idoso de 80 Anos ou mais , AdultoRESUMO
Dimethylsulfoniopropionate (DMSP) is an abundant marine organosulfur compound with roles in stress protection, chemotaxis, nutrient and sulfur cycling and climate regulation. Here we report the discovery of a bifunctional DMSP biosynthesis enzyme, DsyGD, in the transamination pathway of the rhizobacterium Gynuella sunshinyii and some filamentous cyanobacteria not previously known to produce DMSP. DsyGD produces DMSP through its N-terminal DsyG methylthiohydroxybutyrate S-methyltransferase and C-terminal DsyD dimethylsulfoniohydroxybutyrate decarboxylase domains. Phylogenetically distinct DsyG-like proteins, termed DSYE, with methylthiohydroxybutyrate S-methyltransferase activity were found in diverse and environmentally abundant algae, comprising a mix of low, high and previously unknown DMSP producers. Algae containing DSYE, particularly bloom-forming Pelagophyceae species, were globally more abundant DMSP producers than those with previously described DMSP synthesis genes. This work greatly increases the number and diversity of predicted DMSP-producing organisms and highlights the importance of Pelagophyceae and other DSYE-containing algae in global DMSP production and sulfur cycling.
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Filogenia , Compostos de Sulfônio , Compostos de Sulfônio/metabolismo , Cianobactérias/genética , Cianobactérias/metabolismo , Cianobactérias/enzimologia , Metiltransferases/metabolismo , Metiltransferases/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Vias Biossintéticas/genéticaRESUMO
Bioprospecting the secondary metabolism of underexplored Actinomycetota taxa is a prolific route to uncover novel chemistry. In this work, we report the isolation, structure elucidation, and bioactivity screening of cellulamides A and B (1 and 2), two novel linear peptides obtained from the culture of the macroalga-associated Cellulosimicrobium funkei CT-R177. The host of this microorganism, the Chlorophyta Codium tomentosum, was collected in the northern Portuguese coast and, in the scope of a bioprospecting study focused on its associated actinobacterial community, strain CT-R177 was isolated, taxonomically identified, and screened for the production of antimicrobial and anticancer compounds. Dereplication of a crude extract of this strain using LC-HRMS(/MS) analysis unveiled a putative novel natural product, cellulamide A (1), that was isolated following mass spectrometry-guided fractionation. An additional analog, cellulamide B (2) was obtained during the chromatographic process and chemically characterized. The chemical structures of the novel linear peptides, including their absolute configurations, were elucidated using a combination of HRMS, 1D/2D NMR spectroscopy, and Marfey's analysis. Cellulamide A (1) was subjected to a set of bioactivity screenings, but no significant biological activity was observed. The cellulamides represent the first family of natural products reported from the Actinomycetota genus Cellulosimicrobium, showcasing not only the potential of less-explored taxa but also of host-associated marine strains for novel chemistry discovery.
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Peptídeos , Humanos , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/isolamento & purificação , Actinobacteria/química , Actinobacteria/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Organismos Aquáticos , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Linhagem Celular Tumoral , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificaçãoRESUMO
Bioprospecting actinobacterial secondary metabolism from untapped marine sources may lead to the discovery of biotechnologically-relevant compounds. While studying the diversity and bioactive potential of Actinomycetota associated with Codium tomentosum, a green seaweed collected in the northern Portuguese cost, strain CT-F61, identified as Streptomyces violaceoruber, was isolated. Its extracts displayed a strong anticancer activity on breast carcinoma T-47D and colorectal carcinoma HCT116 cells, being effective as well against a panel of human and fish pathogenic bacteria. Following a bioactivity-guided isolation pipeline, a new analogue of the red-pigmented family of the antibiotics prodigiosins, decylprodigiosin (1), was identified and chemically characterized. Despite this family of natural products being well-known for a long time, we report a new analogue and the first evidence for prodigiosins being produced by a seaweed-associated actinomycete.
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PURPOSE: In patients with colorectal cancer (CRC), the most important factor to decide the need of adjuvant chemotherapy is the histological lymph node (LN) evaluation. Our work aimed to give a broad view over the use of methylene blue and its consequences in the number of lymph node harvest. METHODS: PUBMED, WEB OF SCIENCE and EMBASE databases were consulted, retrieving clinical trials, which mentioned the used of intra-arterial methylene blue in patients with colorectal cancer. RESULTS: Eighteen clinical trials analyzing the use of intra-arterial methylene blue in specimens of colorectal cancer were selected. The articles show a statistical difference between the use of methylene blue and the classical dissection in both variable at study. The results of the statistical analysis of the lymph node harvest variable demonstrate a significant statistical difference between the group that received methylene blue injection and the group that underwent conventional dissection. There is a significant statistical difference between the experimental and control groups for the ideal lymph node harvest (lymph node harvest count greater than 12). CONCLUSION: The use of intra-arterial methylene blue revealed a high potential for the quantification of lymph nodes, considering the increase of lymph node harvest and the higher percentage of cases with more than 12 lymph nodes count, albeit the high heterogeneity between the studies in terms of reported results. Future investigations with controlled double blinded studies obtaining better categorized results should be conducted in order to better evaluate this technique and compare it to the current paradigm.
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Neoplasias Colorretais , Azul de Metileno , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/tratamento farmacológico , Excisão de Linfonodo/métodos , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática , PrognósticoRESUMO
Selective COX-2 inhibitors such as etoricoxib (ETX) are potentially indicated for the treatment of intestinal inflammatory disorders. However, their systemic administration provokes some off-site secondary effects, decreasing the desirable local effectiveness. To circumvent such limitations, herein an ETX delivery system based on electrospun fibrous meshes (eFMs) was proposed. ETX at different concentrations (1, 2, and 3 mg mL-1) was loaded into eFMs, which not affect the morphology and the mechanical properties of this drug delivery system (DDS). The ETX showed a burst release within the first 12 h, followed by a faster release until 36 h, gradually decreasing over time. Importantly, the ETX studied concentrations were not toxic to human colonic cells (i.e. epithelial and fibroblast). Moreover, the DDS loading the highest concentration of ETX, when tested with stimulated human macrophages, promoted a reduction of PGE2, IL-8 and TNF-α secretion. Therefore, the proposed DDS may constitute a safe and efficient treatment of colorectal diseases promoted by inflammatory disorders associated with COX-2.
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Inibidores de Ciclo-Oxigenase 2 , Sistemas de Liberação de Medicamentos , Doenças Inflamatórias Intestinais , Humanos , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Inibidores de Ciclo-Oxigenase 2/farmacologia , Dinoprostona , Etoricoxib/administração & dosagem , Etoricoxib/farmacologia , Fator de Necrose Tumoral alfa , Doenças Inflamatórias Intestinais/tratamento farmacológicoAssuntos
Prolapso Retal , Humanos , Prolapso Retal/cirurgia , Resultado do Tratamento , Períneo/cirurgia , RecidivaRESUMO
OBJECTIVE: To evaluate the in hospital and long term outcomes after open or endovascular repair of subclavian and axillary artery injuries. METHODS: This was a retrospective, single centre study. Data were reviewed from patients with subclavian and or axillary injuries who presented to the authors' centre between January 2009 and December 2022. Outcome data included complications, death, amputations, and re-interventions. A p value < .050 was considered to be statistically significant. RESULTS: Over the study period, 62 patients with subclavian or axillary trauma were admitted to the study hospital. Patients were young (median age 32.5 years, range 12 - 53) and most were men (85%); 32 patients experienced blunt trauma, and 30 penetrating trauma. The median injury severity score was 18 (interquartile range [IQR] 9, 34), and 47% of patients had a brachial plexus injury. The arterial injury was occlusion in 62% of patients, and the median ischaemia time was 12.5 hours (IQR 7.13, 24). All patients with subclavian injuries (n = 37) and 13 of 25 patients with an axillary injury underwent endovascular repair (stent graft placement). Open repair was performed in 12 patients with axillary injury (axillobrachial bypass in seven patients). At hospital discharge, the amputation free survival rate was 82% vs. 92% (p = .67), the mortality rate was 10% vs. 8% (p = 1.0), and the amputation rate was 10% vs. 0 (p = .57) for endovascular and open repair, respectively. The mean follow up time was 4.1 ± 3.5 years. After the seven year follow up, the stent primary patency was 42%. No re-interventions or amputations were performed after hospital discharge. Disability was related to fractures and soft tissue and brachial plexus injuries. CONCLUSION: Endovascular treatment was preferred for patients with subclavian artery injuries. Open repair was preferred for patients with penetrating axillary injuries. In hospital and long term complications were related to fractures and soft tissue and brachial plexus injuries, rather than the treatment of arterial injuries. Measures are needed to reduce ischaemia time and improve brachial plexus injury repair.
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[This corrects the article DOI: 10.3389/fmicb.2023.1158441.].
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The deep-sea covers over 70% of the Earth's surface and harbors predominantly uncharacterized bacterial communities. Actinobacteria are the major prokaryotic source of bioactive natural products that find their way into drug discovery programs, and the deep-sea is a promising source of biotechnologically relevant actinobacteria. Previous studies on actinobacteria in deep-sea sediments were either regionally restricted or did not combine a community characterization with the analysis of their bioactive potential. Here we characterized the actinobacterial communities of upper layers of deep-sea sediments from the Arctic and the Atlantic (Azores and Madeira) ocean basins, employing 16S rRNA metabarcoding, and studied the biosynthetic potential of cultivable actinobacteria retrieved from those samples. Metabarcoding analysis showed that the actinobacterial composition varied between the sampled regions, with higher abundance in the Arctic samples but higher diversity in the Atlantic ones. Twenty actinobacterial genera were detected using metabarcoding, as a culture-independent method, while culture-dependent methods only allowed the identification of nine genera. Isolation of actinobacteria resulted on the retrieval of 44 isolates, mainly associated with Brachybacterium, Microbacterium, and Brevibacterium genera. Some of these isolates were only identified on a specific sampled region. Chemical extracts of the actinobacterial isolates were subsequently screened for their antimicrobial, anticancer and anti-inflammatory activities. Extracts from two Streptomyces strains demonstrated activity against Candida albicans. Additionally, eight extracts (obtained from Brachybacterium, Brevibacterium, Microbacterium, Rhodococcus, and Streptomyces isolates) showed significant activity against at least one of the tested cancer cell lines (HepG2 and T-47D). Furthermore, 15 actinobacterial extracts showed anti-inflammatory potential in the RAW 264.4 cell model assay, with no concomitant cytotoxic response. Dereplication and molecular networking analysis of the bioactive actinobacterial extracts showed the presence of some metabolites associated with known natural products, but one of the analyzed clusters did not show any match with the natural products described as responsible for these bioactivities. Overall, we were able to recover taxonomically diverse actinobacteria with different bioactivities from the studied deep-sea samples. The conjugation of culture-dependent and -independent methods allows a better understanding of the actinobacterial diversity of deep-sea environments, which is important for the optimization of approaches to obtain novel chemically-rich isolates.
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Fatty acids are important molecules in bioenergetics and also in industry. The phylum cyanobacteria consists of a group of prokaryotes that typically carry out oxygenic photosynthesis with water as an electron donor and use carbon dioxide as a carbon source to generate a range of biomolecules, including fatty acids. They are also able to import exogenous free fatty acids and direct them to biosynthetic pathways. Here, we review current knowledge on mechanisms and regulation of free fatty acid transport into cyanobacterial cells, their subsequent activation and use in the synthesis of fatty acid-containing biomolecules such as glycolipids and alka(e)nes, as well as recycling of free fatty acids derived from such molecules. This review also covers efforts in the engineering of such cyanobacterial fatty acid-associated pathways en route to optimized biofuel production.
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Cianobactérias , Ácidos Graxos não Esterificados , Ácidos Graxos não Esterificados/metabolismo , Ácidos Graxos/metabolismo , Fotossíntese , Vias BiossintéticasRESUMO
Fatty acid-derived alkyl chains are often found in natural products, where they can exert a number of different functions, most notably biological membrane interactions. Such alkyl chains are difficult to modify regio- and stereoselectively, since most positions are distant from any directing functional group. Chemical and biochemical diversification of these moieties is therefore a challenge, and most organisms do not modify alkyl moieties to a great extent. Still, one particular group of microorgansims - cyanobacteria - display not only a large number of fatty acid-incorporating natural products, but also modify these to a great extent. Here, we provide an overview of the unique fatty acid metabolism of cyanobacteria in the context of natural products biosynthesis. We cover the diverse range of fatty acid incorporation mechanisms that these organisms use to recruit and commit fatty acids to natural products biosynthetic pathways. A variety of alkyl chain decorations and modifications that are found in cyanobacterial natural products are highlighted, illustrating the rich enzymatic arsenal that these organisms have evolved to diversify fatty acid-derived alkyl chains.
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Produtos Biológicos , Cianobactérias , Ácidos Graxos/metabolismo , Produtos Biológicos/química , Cianobactérias/químicaRESUMO
BACKGROUND: Venous compression syndromes are clinical conditions in which the large veins are compressed by other anatomical structures. Laboratory simulations may help us better understand the hemodynamics in venous compressions by creating situations similar to those seen in vivo. The aim of this study is to produce a model of the caval bifurcation using a polymer with distensibility similar to the human vena cava. METHODS: Fragments of the inferior vena cava were collected from 13 deceased kidney donors (aged 15-37 years) and were tested for deformation (strain) when subjected to distension at 50 N/cm2. Strips of 5 different polymers-thermic polyurethane and Agilus30 with Vero Magenta (AV) (in 3 different hardnesses) and silicone-were subjected to the same biomechanical tests and compared with the vena cava. A model of the caval bifurcation was produced with 3-D printing. RESULTS: The deformation (strain) of the vena cava wall was 0.16 ± 0.9 when submitted to stress close to 50 N/cm2. Silicone showed a strain higher than the standard deviation of venous fragments. The strain of AV resin 95 Shore was lower than the standard deviation of the venous fragments. AV Resins 70 and 85 Shore showed strains within the standard deviation of the venous specimen, with 70 Shore being closest to the mean venous strain. Therefore, this material was selected for modeling the caval bifurcation. The computed tomography scan image generated a computer model of the caval bifurcation and was printed in 3 dimensions. In addition, the segments of 2 adjacent vertebrae were also printed to reference the compression site. CONCLUSIONS: The 3-D printing of large veins can produce models with anatomy and biomechanics similar to those of human veins and opens a field of investigation into the hemodynamics of venous compression syndromes. Polymers with Shore A70 appear to have biomechanical properties similar to those of the vena cava wall. The model obtained in this study can be used in several in vitro studies of May-Thurner Syndrome.
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Veias , Veia Cava Inferior , Humanos , Resultado do Tratamento , Veia Cava Inferior/diagnóstico por imagem , Veias/diagnóstico por imagem , Hemodinâmica , Fenômenos BiomecânicosRESUMO
PURPOSE: Postoperative complications after a colonic and rectal surgery are of significant concern to the surgical community. Although there are different techniques to perform anastomosis (i.e., handsewn, stapled, or compression), there is still no consensus on which technique provides the least number of postoperative problems. The objective of this study is to compare the different anastomotic techniques regarding the occurrence or duration of postoperative outcomes such as anastomotic dehiscence, mortality, reoperation, bleeding and stricture (as primary outcomes), and wound infection, intra-abdominal abscess, duration of surgery, and hospital stay (as secondary outcomes). METHODS: Clinical trials published between January 1, 2010, and December 31, 2021, reporting anastomotic complications with any of the anastomotic technique were identified using the MEDLINE database. Only articles that clearly defined the anastomotic technique used, and report at least two of the outcomes defined were included. RESULTS: This meta-analysis included 16 studies whose differences were related to the need of reoperation (p < 0.01) and the duration of surgery (p = 0.02), while for the anastomotic dehiscence, mortality, bleeding, stricture, wound infection, intra-abdominal abscess, and hospital stay, no significant differences were found. Compression anastomosis reported the lowest reoperation rate (3.64%) and the handsewn anastomosis the highest (9.49%). Despite this, more time to perform the surgery was required in compression anastomosis (183.47 min), with the handsewn being the fastest technique (139.92 min). CONCLUSIONS: The evidence found was not sufficient to demonstrate which technique is most suitable to perform colonic and rectal anastomosis, since the postoperative complications were similar between the handsewn, stapled, or compression techniques.
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Abscesso Abdominal , Infecções Intra-Abdominais , Humanos , Grampeamento Cirúrgico , Técnicas de Sutura , Constrição Patológica , Abscesso , Anastomose Cirúrgica/métodos , Complicações Pós-OperatóriasRESUMO
BACKGROUND: The current study aimed to evaluate the distance between the right common iliac artery (RCIA) and lumbar vertebra in asymptomatic patients in order to determine whether such distance was statistically correlated with the left common iliac vein (LCIV) diameter (LCIVD) and to investigate if both measures were related to demographic characteristics and anthropometric data, such as sex, age, height, and body mass index (BMI). METHODS: In this descriptive and uncontrolled anatomic study, data from high-definition computed tomography (CT) angiography images of living kidney donors without a medical history of chronic venous insufficiency or past deep vein thrombosis (DVT) were analyzed. The RCIA crossed over the LCIV in 311 individuals, who were then included in this study. CT scans were reviewed to measure (1) the narrowest space between the RCIA and fifth lumbar vertebral body and (2) the LCIVD. Measures were subjected to normality tests and were divided according to the sex of the study population. Correlations of measures with age, BMI, and height were calculated. RESULTS: Of the 311 patients analyzed, 66.6% (n = 207) were female. The mean lumbar vertebral body-iliac artery distance (LVBIAD) was 7.2 mm, whereas the mean LCIVD was 8.5 mm; both were higher in men (P < 0.001). The statistical analysis of LVBIAD and LCIVD distributions revealed no normality pattern (P < 0.05). The analysis of the correlation between them showed a weak statistically significant relationship with age. A linear regression model considering the normality percentile interval indicated a strong positive correlation between LVBIAD and LCIVD (R2 = 0.884). CONCLUSIONS: The LVBIAD was <5 mm and <3 mm in 25% and 5% of asymptomatic individuals, respectively. The LCIVD correlated with the space between the RCIA and lumbar vertebra. The distance between the RCIA and lumbar vertebra and the LCIVD were higher in male subjects and older patients, but did not correlate with BMI and height.
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Transplante de Rim , Síndrome de May-Thurner , Humanos , Masculino , Feminino , Síndrome de May-Thurner/diagnóstico por imagem , Síndrome de May-Thurner/terapia , Angiografia por Tomografia Computadorizada , Transplante de Rim/efeitos adversos , Resultado do Tratamento , Veia Ilíaca/diagnóstico por imagem , Tomografia Computadorizada por Raios X , AngiografiaRESUMO
Purpose: Haemorrhoids are normal structures in the human body, only seen as pathological when symptomatic. Nowadays, new techniques have surfaced using a diode laser which, after locating the target arteries, blocks the blood flow while hitting and shrinking the local mucosa/submucosa at a depth of 4â mm. Our work aimed to give a broad view over this new technique and its consequences in the post-operative follow-up with a systematic review. Methods: EMBASE and MEDLINE databases were consulted, retrieving clinical trials, which mentioned the use of 980â nm diode laser on the treatment of haemorrhoids. Results: Ten clinical trials analyzing the post-operative effects of laser haemorrhoidectomy were selected, including 2 randomized controlled clinical trials and 1 controlled clinical trial. The overall quality of the trials was low, indicating a high risk of bias. Conclusion: The laser haemorrhoidectomy procedure revealed a high therapeutic potential, considering the reduced number of postoperative complaints (bleeding/pain), the high symptom resolution and the reduced recurrence, albeit the high heterogeneity between the studies in terms of reported results. Future investigations with higher quality and controlled double-blinded studies obtaining better-categorized results should be conducted in order to better evaluate this procedure and compare it to the current paradigm.
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The morphology, 16S rRNA gene phylogeny and 16S-23S rRNA gene ITS secondary structures of three strains of marine Cyanobacteria, isolated from inter- and subtidal environments from north Portugal were studied, resulting in the description of Zarconia navalis gen. nov., sp. nov. (Oscillatoriales incertae sedis), Romeriopsis navalis gen. nov., sp. nov. (Leptolyngbyaceae) and Romeriopsis marina sp. nov., named under the International Code of Nomenclature for algae, fungi, and plants. No diacritical morphological characters were found for the new genera and species. The 16S rRNA gene maximum-likelihood and Bayesian phylogenies supported that the genus Zarconia is a member of the Oscillatoriales, morphologically similar to the genera Microcoleus and Phormidium, but distant from them. The genus Romeriopsis is positioned within the Leptolyngbyaceae (Synechococcales) and is closely related to Alkalinema. The secondary structures of the D1-D1', Box B, V2 and V3 helices corroborate the phylogenetic results. Furthermore, our study supports previous observations of polyphyletic Oscillatoriales families and reinforces the need for their taxonomic revision.
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Cianobactérias , Ácidos Graxos , Humanos , RNA Ribossômico 16S/genética , Filogenia , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Teorema de Bayes , Portugal , Composição de Bases , Ácidos Graxos/químicaRESUMO
INTRODUCTION: Hemodynamic Depression (HD) characterized by hypotension and bradycardia is a complication of carotid surgery due to direct autonomic stimulation in the carotid sinus. The authors believe the incidence of HD is high and possibly related to major cardiac complications. METHODS: Analysis of patient records during admissions for carotid surgery between January 2014 and December 2018 in two hospitals. HD was defined as bradycardia or hypotension in the first 24 postoperative hours. Bradycardia was defined as heart rate < 50bpm; hypotension as systolic blood pressure < 90 mmHg, continuous use of vasopressors, or a drop in SBP > 20% compared to preoperative values. Myocardial infarction, stroke, and cardiovascular death were defined as adverse events. RESULTS: Overall, 237 carotid surgeries (178 endarterectomies, 59 angioplasties) were studied, and the global incidence of HD was 54.4% (hypotension in 50.2%, bradycardia in 11.0%, and hypotension and bradycardia in 6.8%). The independent predictors of HD were asymptomatic carotid stenosis (OR = 1.824; 95% CI 1.014-3.280; p = 0.045), endovascular surgery (OR = 3.319; 95% CI 1.675-6.576; p = 0.001) and intraoperative hypotension or bradycardia (OR = 2.144; 95% CI 1.222-3.762; p = 0.008). Hypotension requiring continuous vasopressor infusion was the only factor independently associated with adverse cardiovascular events (OR = 5.504; 95% CI 1.729-17.529; p = 0.004). DISCUSSION/CONCLUSION: Incidence of Hemodynamic Depression after carotid surgery is high and independently associated with surgical technique, symptomatic repercussion of the carotid stenosis, and intraoperative hypotension or bradycardia. Hypotension requiring the continuous infusion of vasopressors was independently associated with the occurrence of MACE.