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1.
PLoS One ; 18(10): e0287376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37796854

RESUMO

The Antarctic toothfish (Dissostichus mawsoni) is the largest notothenioid species in the Southern Ocean, playing a keystone role in the trophic web as a food source for marine mammals and a top predator in deep-sea ecosystems. Most ecological knowledge on this species relies on samples from areas where direct fishing is allowed, whereas in areas closed to fishing, such as the Antarctic Peninsula (AP), there are still key ecological gaps to ensure effective conservation, especially regarding our understanding of its trophic relationships within the ecosystem. Here, we present the first comprehensive study of the feeding behavior of Antarctic toothfish caught in the northern tip of the AP, during two consecutive fishing seasons (2019/20 and 2020/21). Stomach content was analyzed according to size-classes, sex and season. Macroscopic morphological analysis was used to identify prey, whereas DNA analysis was used in highly digested prey items. Fatty acid analysis was conducted to determine the prey's nutritional composition. The diet mainly consisted of Macrouridae, Cephalopoda, Anotopteridae, and Channichthyidae. Other prey items found were crustaceans and penguin remains; however, these were rare in terms of their presence in stomach samples. Sex had no effect on diet, whereas size-class and fishing season influenced prey composition. From 27 fatty acid profiles identified, we observed two different prey groups of fishes (integrated by families Anotopteridae, Macrouridae and Channichthyidae) and cephalopods. Our results revealed a narrow range of prey items typical of a generalist predator, which probably consumes the most abundant prey. Understanding the diet and trophic relationships of Antarctic toothfish is critical for a better comprehension of its role in the benthic-demersal ecosystem of the AP, key for ecosystemic fisheries management, and relevant for understanding and predicting the effect of climate change on this species.


Assuntos
Ecossistema , Perciformes , Humanos , Animais , Ácidos Graxos , Regiões Antárticas , Dieta , Cadeia Alimentar , Mamíferos
2.
Front Cell Infect Microbiol ; 12: 867205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36017363

RESUMO

Background: Diarrheagenic E. coli (DEC) pathogenicity relies on the interaction of bacteria with the host's gut environment, which is regulated by the resident microbiota. Previously, we identified indicative bacterial species of gut microbiota in DEC-positive stool samples from children. Here, we evaluated the role of two indicative species, Citrobacter werkmanii (CW) and Escherichia albertii (EA), in the virulence of two DEC pathotypes, Shiga toxin-producing (STEC) and enteroaggregative (EAEC) Escherichia coli. Methods: We determined the effect of supernatants obtained from CW and EA cultures on the gene expression of STEC strain 86-24 and EAEC strain 042 by RNA-seq analysis. We evaluated IL-8 secretion from T84 cells infected with these DEC strains in the presence or absence of the supernatant from EA. The effect of the supernatant from EA on the growth and adherence of STEC and EAEC to cells was also evaluated. Finally, we studied the effect of the EA supernatant on the STEC-induced inflammation mediated by the long polar fimbriae (Lpf) in T84 cells and the expression of plasmid-encoded toxin (Pet) in EAEC. Results: RNA-seq analysis revealed that several virulence factors in STEC and EAEC were upregulated in the presence of supernatants from CW and EA. Interestingly, an increase in the secretion of IL-8 was observed in cells infected with STEC or EAEC in the presence of a supernatant from EA. Similar results were observed with the supernatants obtained from clinical strains of E. albertii. The supernatant from EA had no effect on the growth of STEC and EAEC, or on the ability of these DEC strains to adhere to cells. We found that Pet toxin in EAEC was upregulated in the presence of a supernatant from EA. In STEC, using mutant strains for Lpf fimbriae, our data suggested that these fimbriae might be participating in the increase in IL-8 induced by STEC in cells in the presence of a supernatant from EA. Conclusion: Supernatant obtained from an indicative species of DEC-positive diarrhea could modulate gene expression in STEC and EAEC, and IL-8 secretion induced by these bacteria. These data provide new insights into the effect of gut microbiota species in the pathogenicity of STEC and EAEC.


Assuntos
Infecções por Escherichia coli , Microbioma Gastrointestinal , Criança , Diarreia/microbiologia , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Humanos , Interleucina-8 , Toxina Shiga , Virulência
3.
Microb Cell ; 8(9): 223-238, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34527721

RESUMO

Inflammatory bowel diseases (IBDs), which include ulcerative colitis (UC) and Crohn's disease (CD), cause chronic inflammation of the gut, affecting millions of people worldwide. IBDs have been frequently associated with an alteration of the gut microbiota, termed dysbiosis, which is generally characterized by an increase in abundance of Proteobacteria such as Escherichia coli, and a decrease in abundance of Firmicutes such as Faecalibacterium prausnitzii (an indicator of a healthy colonic microbiota). The mechanisms behind the development of IBDs and dysbiosis are incompletely understood. Using samples from colonic biopsies, we studied the mucosa-associated intestinal microbiota in Chilean and Spanish patients with IBD. In agreement with previous studies, microbiome comparison between IBD patients and non-IBD controls indicated that dysbiosis in these patients is characterized by an increase of pro-inflammatory bacteria (mostly Proteobacteria) and a decrease of commensal beneficial bacteria (mostly Firmicutes). Notably, bacteria typically residing on the mucosa of healthy individuals were mostly obligate anaerobes, whereas in the inflamed mucosa an increase of facultative anaerobe and aerobic bacteria was observed. We also identify potential co-occurring and mutually exclusive interactions between bacteria associated with the healthy and inflamed mucosa, which appear to be determined by the oxygen availability and the type of respiration. Finally, we identified a panel of bacterial biomarkers that allow the discrimination between eubiosis from dysbiosis with a high diagnostic performance (96% accurately), which could be used for the development of non-invasive diagnostic methods. Thus, this study is a step forward towards understanding the landscapes and alterations of mucosa-associated intestinal microbiota in patients with IBDs.

4.
Cancer Immunol Immunother ; 70(6): 1691-1704, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33388994

RESUMO

BACKGROUND: Anti-PD-(L)1 blocking agents can induce immune-related adverse events (irAEs), which can compromise treatment continuation. Since circulating leukocyte-platelet (PLT) complexes contribute to inflammatory and autoimmune diseases, we aimed to analyze the role of these complexes as predictors of irAEs in non-small cell lung cancer (NSCLC) patients receiving anti-PD-(L)1. MATERIALS AND METHODS: Twenty-six healthy donors (HD) and 87 consecutive advanced NSCLC patients treated with anti-PD-(L)1 were prospectively included. Percentages of circulating leukocyte-PLT complexes were analyzed by flow cytometry and compared between HD and NSCLC patients. The association of leukocyte-PLT complexes with the presence and severity of irAEs was analyzed. RESULTS: NSCLC patients had higher percentages of circulating leukocyte-PLT complexes. Higher percentages of monocytes with bound PLT (CD14 + PLT +) were observed in patients who received prior therapies while CD4 + T lymphocytes with bound PLT (CD4 + PLT +) correlated with platelets counts. The CD4 + PLT + high percentage group presented a higher rate of dermatological irAEs while the CD4 + PLT + low percentage group showed a higher rate of non-dermatological irAEs (p < 0.001). A lower frequency of grade ≥ 2 irAEs was observed in the CD4 + PLT + high percentage group (p < 0.05). Patients with CD4 + PLT + low and CD14 + PLT + high percentages presented a higher rate of grade ≥ 3 irAEs and predominantly developed non-dermatological irAEs (p < 0.01). CONCLUSIONS: Our results suggest that circulating leukocyte-PLT complexes and the combination of CD4 + PLT + and CD14 + PLT + percentages can be used as a predictive biomarker of the development and severity of irAEs in advanced NSCLC patients receiving anti-PD-(L)1 agents.


Assuntos
Antígeno B7-H1/metabolismo , Plaquetas/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Inibidores de Checkpoint Imunológico/efeitos adversos , Leucócitos/patologia , Neoplasias Pulmonares/tratamento farmacológico , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Idoso , Biomarcadores Tumorais/análise , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida
5.
Front Microbiol ; 12: 793050, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069488

RESUMO

Gut microbiota composition during the first years of life is variable, dynamic and influenced by both prenatal and postnatal factors, such as maternal antibiotics administered during labor, delivery mode, maternal diet, breastfeeding, and/or antibiotic consumption during infancy. Furthermore, the microbiota displays bidirectional interactions with infectious agents, either through direct microbiota-microorganism interactions or indirectly through various stimuli of the host immune system. Here we review these interactions during childhood until 5 years of life, focusing on bacterial microbiota, the most common gastrointestinal and respiratory infections and two well characterized gastrointestinal diseases related to dysbiosis (necrotizing enterocolitis and Clostridioides difficile infection). To date, most peer-reviewed studies on the bacterial microbiota in childhood have been cross-sectional and have reported patterns of gut dysbiosis during infections as compared to healthy controls; prospective studies suggest that most children progressively return to a "healthy microbiota status" following infection. Animal models and/or studies focusing on specific preventive and therapeutic interventions, such as probiotic administration and fecal transplantation, support the role of the bacterial gut microbiota in modulating both enteric and respiratory infections. A more in depth understanding of the mechanisms involved in the establishment and maintenance of the early bacterial microbiota, focusing on specific components of the microbiota-immunity-infectious agent axis is necessary in order to better define potential preventive or therapeutic tools against significant infections in children.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33072619

RESUMO

Background: Diarrheagenic Escherichia coli (DEC) strains are a main cause of diarrhea worldwide in children under 5 years old. DEC virulence is strongly regulated by environmental conditions and metabolites produced by the gut microbiota in the intestinal tract. In this study, we evaluated changes in gut microbiota-metabolome in children with or without diarrhea produced by DEC pathotypes. Goal: To determine gut microbiota composition and metabolome in stool samples obtained from healthy children and children with diarrhea positive for DEC pathotypes. Methods: We analyzed a total of 16 age-paired stool samples: 8 diarrheal samples positive for one DEC pathotype and 8 stool samples from healthy children. To identify the microbiota composition, we sequenced the V3-V4 region of the 16S rRNA and determined operational phylogenetic units (OPU). OPU were then used to predict metabolic pathways using the PICRUSt2 software. The presence of metabolites in stool samples was determined by LC-MS. A correlation analysis was performed with the main genera from each group and main metabolites. Bacteria associated with variance of main metabolites were identified using the MIMOSA2 software. Results: DEC and healthy groups showed a statistically different microbiota composition. A decrease in Firmicutes together with an increase in Bacteroidetes and Proteobacteria was found in the DEC group compared to the healthy group. Metabolic pathway predictions based on microbiota diversity showed that pathways involved in histidine and L-ornithine metabolism were significantly different between groups. A total of 88 metabolites detected by LC-MS were included in the metabolome analysis. We found higher levels of histamine and lower levels of ornithine in DEC samples than in the healthy group. Histamine and L-ornithine were associated with a specific microbiota species and the corresponding metabolic pathways. Conclusion: Stool samples from healthy children and children positive for DEC displayed a differential metabolome and microbiota composition. A strong correlation between a gut microbiota species and certain metabolites, such as histamine and L-ornithine, was found in the DEC group. This information might be useful to identify mechanisms and signaling molecules involved in the crosstalk between microbiota and DEC pathotypes.


Assuntos
Infecções por Escherichia coli , Microbioma Gastrointestinal , Criança , Pré-Escolar , Diarreia , Escherichia coli/genética , Humanos , Metaboloma , Filogenia , RNA Ribossômico 16S/genética
7.
Sci Total Environ ; 748: 142448, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113697

RESUMO

In the Southern Ocean, warming and freshening are expected to be prominent signals of climate change and the reduced ability of Antarctic marine organisms to cope with changing environmental conditions could challenge their future survival. The Antarctic limpet Nacella concinna is a macroinvertebrate of rocky ecosystems, which occurs in high densities in the shallow subtidal zone. Subtidal individuals were exposed to a combination of temperatures (1, 4, 8, 11, 14 °C) and salinities (20 and 30 psu) for a 60-day period. A drastic increment in mortality was observed with seawater warming, showing that N. concinna is highly stenothermal, with limited ability to survive at temperatures warmer than 4 °C, although there was some degree of acclimation at 4 °C and ambient salinity (30 psu). This study confirmed the stenohaline characteristic of this species, with mortality reaching 50% and lower scope for growth at low salinity (20 psu) even at the control temperature (1 °C). At the sub-cellular level, limpets' low tolerance to out-of range salinity is illustrated by the activation of cell remodelling processes whereas the down-regulation of chaperones proteins and plasma membrane ATPase suggest that under the combination of warming and freshening N. concinna experiences a severe level of stress and devote much of its energy to somatic maintenance and survival. The drastic effect observed can be explained by its subtidal origin, an environment with more stable conditions. The surviving individuals at 1 °C and lowered salinity (20 psu) were either more tolerant or showing signs of acclimation after 60 days, but the combination of warming and freshening have a greater combined stress. Projections of climate change for end of the century for this part of the Antarctic can, therefore, result in a significant diminution of the subtidal population of N. concinna, affecting ecological interactions and diversity of the food web.


Assuntos
Ecossistema , Gastrópodes , Animais , Regiões Antárticas , Humanos , Oceanos e Mares , Água do Mar , Temperatura , Transcriptoma
8.
Front Oncol ; 10: 1677, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014837

RESUMO

Background: Immune-related adverse events (irAEs) have been associated with improved efficacy in advanced non-small cell lung cancer (NSCLC) patients receiving anti-PD-(L)1 blockade agents, while the concurrent use of corticosteroids seems to worsen it. We evaluated outcomes in advanced NSCLC patients treated with anti-PD-(L)1 blockade agents in relation to the presence of irAEs and the reasons for using corticosteroids: whether for palliative cancer-related reasons or for the management of irAEs. Methods: Clinical outcomes in advanced NSCLC patients treated with anti-PD-(L)1 blockade agents were calculated with regard to the presence of irAEs and the use of corticosteroids. A landmark analysis was performed to avoid immortal time bias due to the time-dependent nature of irAEs. Results: Out of a total of 267 patients, the 56.9% of patients who experienced irAEs had significantly improved outcomes. In the landmark analysis, median progression-free survival (PFS) was 12.4 months for patients with irAEs vs. 4.1 months for patients without irAEs (p < 0.001), while median overall survival (OS) was 28.2 vs. 12.5 months, respectively (p < 0.001). Likewise, objective response and disease control rates were significantly higher in patients experiencing irAEs: 48.6 vs. 22.8% and 77.1 vs. 39.6% (p < 0.001), respectively. Median OS was significantly shorter for patients receiving ≥10 mg of prednisone equivalent daily for cancer-related symptoms than for the rest of patients (<10 mg prednisone equivalent daily or for management of irAEs): 6 vs. 15.9 months (p < 0.001). Conclusions: IrAEs were associated with improved efficacy in advanced NSCLC patients when a landmark analysis was applied. Patients receiving corticosteroids had significantly poorer outcomes when they were used for cancer-related symptoms.

9.
Rev Chilena Infectol ; 37(3): 276-280, 2020 Jun.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-32853320

RESUMO

The global shortage of reagents and kits for nucleic acid extraction and molecular detection of SARS-CoV-2 requires new cost-effective strategies for the diagnosis of suspected COVID-19 cases, especially in countries that need to increase detection capacity. Pooled nucleic acid testing has been extensively used as a cost-effective strategy for HIV, HepB, HepC and influenza. Also, protocols dispensing of RNA extraction appears as an attractive option for detection of SARS-CoV-2. In this study, we found that pooling of 5 samples showed that CT variations were in the range of 1.0-4,5 units, with less likelihood of a false negative result. Results of the sample without nucleic acid ex-traction, was unsatisfactory, with a significant increase in CT values, and thus for risk of a false negative result. In conclusion, pooling nasopharyngeal samples with both automated and manual extraction proved reliable, and thus a potential efficient alternative for the diagnosis of suspected COVID-19 in developing countries.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Países em Desenvolvimento , Humanos , Pneumonia Viral/diagnóstico , RNA Viral , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2
10.
Rev. chil. infectol ; 37(3): 276-280, jun. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1126120

RESUMO

Abstract The global shortage of reagents and kits for nucleic acid extraction and molecular detection of SARS-CoV-2 requires new cost-effective strategies for the diagnosis of suspected COVID-19 cases, especially in countries that need to increase detection capacity. Pooled nucleic acid testing has been extensively used as a cost-effective strategy for HIV, HepB, HepC and influenza. Also, protocols dispensing of RNA extraction appears as an attractive option for detection of SARS-CoV-2. In this study, we found that pooling of 5 samples showed that CT variations were in the range of 1.0-4,5 units, with less likelihood of a false negative result. Results of the sample without nucleic acid ex-traction, was unsatisfactory, with a significant increase in CT values, and thus for risk of a false negative result. In conclusion, pooling nasopharyngeal samples with both automated and manual extraction proved reliable, and thus a potential efficient alternative for the diagnosis of suspected COVID-19 in developing countries.


Resumen La escasez mundial de reactivos para la extracción de ácidos nucleicos y la detección molecular de SARS-CoV-2 requiere de nuevas estrategias de mayor rendimiento para el diagnóstico de casos sospechosos de COVID-19, especialmente en países que necesitan aumentar su capacidad diagnóstica. La detección de ácidos nucleicos en muestras agrupadas o pool testing se ha utilizado ampliamente como una estrategia costo-efectiva para el VIH, hepatitis B, hepatitis C e influenza. Adicionalmente, los protocolos que no requieren extracción de ARN aparecen como una opción para la detección de SARS-CoV-2. En este trabajo, presentamos los resultados de una estrategia detección de SARS-CoV-2 en muestras agrupadas, que incluye diferentes métodos de extracción de ARN que puede ser una estrategia atractiva para los países en desarrollo. La agrupación de 5 muestras mostró variaciones CT en el rango de 1,0 a 4,5 unidades, con una baja probabilidad de obtener falsos negativos, a diferencias de los resultados agregando muestras agrupadas directamente en la reacción de amplificación de SARS-CoV-2. En conclusión, la agrupación de muestras nasofaríngeas, demostró ser un método confiable y, por lo tanto, una alternativa para aumentar el rendimiento en el diagnóstico de COVID-19 para países en desarrollo.


Assuntos
Humanos , Pneumonia Viral/diagnóstico , Infecções por Coronavirus/diagnóstico , Pandemias , RNA Viral , Técnicas de Laboratório Clínico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Países em Desenvolvimento
11.
Rev. Méd. Clín. Condes ; 31(1): 42-49, ene.-feb. 2020. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1223303

RESUMO

Las personas mayores con fractura de cadera tienen un aumento del riesgo de mortalidad de 5 a 8 veces por todas las causas, y un riesgo mucho mayor de institucionalización por pérdida funcional, ya que solo el 50% de los pacientes que sobreviven, recuperan la actividad de la vida diaria previa a la fractura. Las intervenciones para prevenir dichos resultados, incluyendo una segunda fractura, se transforma en el objetivo principal en estos pacientes. El modelo de atención de ortogeriatría es un enfoque de atención multidimensional para los pacientes que sufren una fractura de cadera, que por lo general, es secundario a una caída desde su propia altura, conocida como fractura por fragilidad. Este modelo de atención desarrollado por geriatras y traumatólogos con la asistencia de un equipo multidisciplinario, incluye una evaluación integral perioperatoria y un equipo de enfermería centrada en la función premórbida del paciente, la cognición, las comorbilidades, que permite crear un plan individualizado, para ser monitorizado y asegurar su cumplimiento, los primeros dos años después de la fractura. Este esquema de trabajo ha demostrado mejorar el retorno a la función previa y la disminución de la mortalidad, con un costo reducido o un aumento de utilidad expresada en calidad de vida, por lo que es la atención más rentable para los pacientes que sufren una fractura de cadera.


Older people with hip fracture have an increased risk of mortality 5 to 8 times, for all causes and a much higher risk of institutionalization due to functional loss, because only 50% of patients who survive, recover the activity of daily life before the fracture. Interventions to prevent such results, including a second fracture, become the principal objective in these patients. The orthogeriatric care model, is a multidimensional approach for patients who suffer a hip fracture, which is usually secondary to a fall from their own height, known as a fragility fracture. This model of care developed by geriatricians and traumatologists with help of a multidisciplinary team, includes a comprehensive perioperative assessment and a nursing team focused on the premorbid patient state, cognition, comorbidities, which allows creating an individualized plan, to be monitored and ensure compliance, the first 2 years. This work scheme has been shown to improve the return of the function and the reduction of mortality at a reduced cost or an expressed utility in quality of life, making it the most cost-effective care for patients suffering from a hip fracture.


Assuntos
Humanos , Idoso , Fraturas Ósseas/prevenção & controle , Fraturas Ósseas/epidemiologia , Geriatria/organização & administração , Equipe de Assistência ao Paciente , Idoso Fragilizado , Fraturas do Quadril/cirurgia , Fraturas do Quadril/economia
12.
Artigo em Inglês | MEDLINE | ID: mdl-29977866

RESUMO

Introduction: Compared to bovine formula (BF), breast milk (BM) has unique properties. In the newborn intestine, there is a homeostatic balance between the counterparts of the immune system, which allows a physiological inflammation, modulated by the gut microbiota. Many studies have attempted to understand the effect of BF vs. BM, and the changes in the gut microbiota, but few also focus on intestinal inflammation. Methods: We conducted a cohort study of newborn infants during their first 3 months. In stool samples taken at 1 and 3 months (timepoints T1 and T3), we quantified calprotectin, IL-8 and α1-antitrypsin by ELISA and we evaluated the expression of IL8 and IL1ß genes by RT-qPCR. To determine the microbiota composition, the 16S rRNA gene was amplified and sequenced using 454 pyrosequencing. Sequences were clustered into operational taxonomic units (OTUs). Results: In total 15 BM and 10 BF infants were enrolled. In the BM group, we found calprotectin and α1-antitrypsin levels were significantly elevated at T3 compared to T1; no differences were found between T1 and T3 in the BF group. A comparison between the BM and BF groups showed that calprotectin levels at T1 were lower in the BM than the BF group; this difference was not observed at T3. For IL-8 levels, we found no differences between groups. A gene expression analysis of the IL8 and IL1ß genes showed that infants from the BF group at T1 have a significantly increased expression of these markers compared to the BM group. Gut microbiota analyses revealed that the phylum Bacteroidetes was higher in BM than BF, whereas Firmicutes were higher in BF. A redundancy analysis and ANOVA showed BM has a community structure statistically different to BF at T1 but not at T3. Compared to BF, BM at T1 showed a higher representation of Enterococcus, Streptococcus, Enterobacter, Lactococcus, and Propionibacterium. Conclusions: We found a basal state of inflammation in the infants' intestine based on inflammation markers. One month after birth, infants receiving BF exhibited higher levels of inflammation compared to BM.


Assuntos
Fórmulas Infantis/microbiologia , Inflamação/microbiologia , Intestinos/microbiologia , Microbiota/imunologia , Leite Humano/microbiologia , Bacteroidetes/genética , Bacteroidetes/imunologia , Chile , Estudos de Coortes , Firmicutes/genética , Firmicutes/imunologia , Humanos , Sistema Imunitário/imunologia , Sistema Imunitário/microbiologia , Lactente , Recém-Nascido , Inflamação/imunologia , Inflamação/patologia , Intestinos/imunologia , Intestinos/patologia , Complexo Antígeno L1 Leucocitário/análise , Microbiota/genética , alfa 1-Antitripsina/análise
13.
Artigo em Inglês | MEDLINE | ID: mdl-29075617

RESUMO

Background: Diarrheagenic Escherichia coli (DEC) strains are a major cause of diarrhea in children under 5 years of age worldwide. DEC pathogenicity relies on the interaction of bacteria with environmental factors, including the host's resident gut microbiota. Previous reports have shown changes in the gut microbiota's composition during episodes of diarrhea, which may increase the pathogenicity of DEC strains. More intense and detailed identification of microbiota strains specifically associated with DEC infections and disease is needed to pinpoint their role in DEC pathogenicity. Aim: To identify resident indicative bacterial taxa in DEC-positive diarrhea stool samples of Chilean children. Methods: We analyzed 63 diarrheal stool samples from children 1-5 years of age by FilmArray® GI in order to identify a potential pathogen and to group diarrhea episodes into those caused by DEC as sole pathogen (DEC group, 32 samples) and those caused by an enteric virus as sole pathogen (viral group, 31 samples). In addition, 30 stool samples from healthy children, negative for enteric pathogens, were evaluated (healthy group). The 16S rRNA gene was amplified and sequenced using 454 pyrosequencing. Sequences were clustered into operational taxonomic units (OTUs) at 99% identity and their representatives were used to assign them to operational phylogenetic units (OPUs) using a phylogenetic inference approach. Results: Taxa assignment using the OPU approach resulted in a lower number of units but with higher accuracy compared to the OTU approach. Data analysis indicated an increase in sequences belonging to the phylum Proteobacteria in the DEC group compared to the viral and healthy groups. Samples displayed a statistically different community structure by sample grouping by redundancy analysis and ANOVA. Escherichia albertii (p = 0.001), Citrobacter werkmanii (p = 0.001), Yersinia enterocolitica, subsp. paleartica (p = 0.048), and Haemophilus sputorum (p = 0.028) were indicative species for the DEC group as compared to the viral and healthy groups. Conclusion: Gut microbiota in Chilean children with DEC-positive diarrhea differed from microbiota associated with enteric virus and healthy children. Indicative species found in this study may prove relevant in advancing our understanding of the relationship between resident gut microbiota and DEC leading to the occurrence of disease.


Assuntos
Diarreia/microbiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli/patogenicidade , Microbioma Gastrointestinal/genética , Trato Gastrointestinal/microbiologia , Pré-Escolar , Chile/epidemiologia , Estudos de Coortes , Diarreia/epidemiologia , Infecções por Escherichia coli/epidemiologia , Fezes/microbiologia , Humanos , Lactente , Filogenia , RNA Ribossômico 16S/genética
14.
Rep Pract Oncol Radiother ; 22(3): 251-257, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28479874

RESUMO

OBJECTIVES: Ki-67 is a proliferation marker in prostate cancer. A prognostic RNA signature was developed to characterize prostate cancer aggressiveness. The aim was to evaluate prognostic correlation of CCP and Ki-67 with biochemical failure (BF), and survival in high-risk prostate cancer patients (pts) treated with radiation therapy (RT). METHODS: CCP score and Ki-67 were derived retrospectively from pre-treatment paraffin-embedded prostate cancer tissue of 33 men diagnosed from 2002 to 2006. CCP score was calculated as an average expression of 31 CCP genes. Ki-67 was determined by IHC. Single pathologist evaluated all tissues. Factors associated to failure and survival were analyzed. RESULTS: Median CCP score was 0.9 (-0-1 - 2.6). CCP 0: 1 pt; CCP 1: 19 pts; CCP 2: 13 pts. Median Ki-67 was 8.9. Ki-67 cutpoint was 15.08%. BF and DSM were observed in 21% and 9%. Ki-67 ≥ 15% predicted BF (p = 0.043). With a median follow-up of 8.4 years, 10-year BF, OS, DM and DSM for CCP 1 vs. CCP 2 was 76-71% (p = 0.83), 83-73% (p = 0.86), 89-85% (p = 0.84), and 94-78% (p = 0.66). On univariate, high Ki-67 was correlated with BF (p = 0.013), OS (p = 0.023), DM (p = 0.007), and DSM (p = 0.01). On Cox MVA, high Ki-67 had a BF trend (p = 0.063). High CCP score was not correlated with DSM. CONCLUSIONS: High Ki-67 significantly predicted outcome and provided prognostic information. CCP score may improve accuracy stratification. We did not provide prognostic correlation of CCP and DSM. It should be validated in a larger cohort of pts.

15.
Evol Appl ; 10(4): 402-416, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28352299

RESUMO

Invasive species have become widespread in aquatic environments throughout the world, yet there are few studies that have examined genomic variation of multiple introduced species in newly colonized environments. In this study, we contrast genomic variation in two salmonid species (anadromous Chinook Salmon, Oncorhynchus tshawytscha, 11,579 SNPs and resident Brook Charr Salvelinus fontinalis, 13,522 SNPs) with differing invasion success after introduction to new environments in South America relative to populations from their native range in North America. Estimates of genetic diversity were not significantly different between introduced and source populations for either species, indicative of propagule pressure that has been shown to maintain diversity in founding populations relative to their native range. Introduced populations also demonstrated higher connectivity and gene flow than those in their native range. Evidence for candidate loci under divergent selection was observed, but was limited to specific introduced populations and was not widely evident. Patterns of genomic variation were consistent with general dispersal potential of each species and therefore also the notion that life history variation may contribute to both invasion success and subsequent genetic structure of these two salmonids in Patagonia.

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