High Salt Levels Reduced Dissimilarities in Root-Associated Microbiomes of Two Barley Genotypes.

Plants harbor in and at their roots bacterial microbiomes that contribute to their health and fitness. The microbiome composition is controlled by the environment and plant genotype. Previously, it was shown that the plant genotype-dependent dissimilarity of root microbiome composition of different species becomes smaller under drought stress. However, it remains unknown whether this reduced plant genotype-dependent effect is a specific response to drought stress or a more generic response to abiotic stress. To test this, we studied the effect of salt stress on two distinct barley (Hordeum vulgare L.) genotypes: the reference cultivar Golden Promise and the Algerian landrace AB. As inoculum, we used soil from salinized and degraded farmland on which barley was cultivated. Controlled laboratory experiments showed that plants inoculated with this soil displayed growth stimulation under high salt stress (200 mM) in a plant genotype-independent manner, whereas the landrace AB also showed significant growth stimulation at low salt concentrations. Subsequent analysis of the root microbiomes revealed a reduced dissimilarity of the bacterial communities of the two barley genotypes in response to high salt, especially in the endophytic compartment. High salt level did not reduce α-diversity (richness) in the endophytic compartment of both plant genotypes but was associated with an increased number of shared strains that respond positively to high salt. Among these, Pseudomonas spp. were most abundant. These findings suggest that the plant genotype-dependent microbiome composition is altered generically by abiotic stress.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

A genetically and functionally diverse group of non-diazotrophic Bradyrhizobium spp. colonizes the root endophytic compartment of Arabidopsis thaliana.

BACKGROUND: Diazotrophic Bradyrhizobium spp. are well known for their ability to trigger nodule formation on a variety of legume species. In nodules, Bradyrhizobium utilizes plant-derived carbohydrates in exchange for fixed nitrogen. The genes essential for the nodulation and nitrogen-fixation trait are clustered in a genomic region, which is known as the 'symbiotic island'. Recently, novel non-diazotrophic Bradyrhizobium spp. have been found to be highly abundant in soils, suggesting that these species can also have a 'free-living' life history. However, whether non-diazotrophic Bradyrhizobium spp. can live in association with plants remains elusive. RESULTS: In this study, we show that Bradyrhizobium spp. are common root endophytes of non-legume plant species - including Arabidopsis thaliana (Arabidopsis) - grown in an ecological setting. From a single Arabidopsis root, four Bradyrhizobium sp. strains (designated MOS001 to MOS004) were isolated. Comparative genome analysis revealed that these strains were genetically and functionally highly diverse, but did not harbour the nodulation and the nitrogen fixation gene clusters. Comparative colonization experiments, with MOS strains and nitrogen-fixing symbiotic strains, revealed that all tested Bradyrhizobium spp. can colonize the root endophytic compartment of Arabidopsis. CONCLUSION: This study provides evidence that both diazotrophic and non-diazotrophic Bradyrhizobium spp. colonize the root endophytic compartment of a wide variety of plant species, including the model species Arabidopsis. This demonstrates that plant roots form a major ecological niche for Bradyrhizobium spp., which might be ancestral to the evolution of the nodulation and nitrogen-fixation trait in this genus.

Synthetic bacterial community derived from a desert rhizosphere confers salt stress resilience to tomato in the presence of a soil microbiome.

The root bacterial microbiome is important for the general health of the plant. Additionally, it can enhance tolerance to abiotic stresses, exemplified by plant species found in extreme ecological niches like deserts. These complex microbe-plant interactions can be simplified by constructing synthetic bacterial communities or SynComs from the root microbiome. Furthermore, SynComs can be applied as biocontrol agents to protect crops against abiotic stresses such as high salinity. However, there is little knowledge on the design of a SynCom that offers a consistent protection against salt stress for plants growing in a natural and, therefore, non-sterile soil which is more realistic to an agricultural setting. Here we show that a SynCom of five bacterial strains, originating from the root of the desert plant Indigofera argentea, protected tomato plants growing in a non-sterile substrate against a high salt stress. This phenotype correlated with the differential expression of salt stress related genes and ion accumulation in tomato. Quantification of the SynCom strains indicated a low penetrance into the natural soil used as the non-sterile substrate. Our results demonstrate how a desert microbiome could be engineered into a simplified SynCom that protected tomato plants growing in a natural soil against an abiotic stress.

Preoperative laparoscopy and peritoneal lavage in gastric adenocarcinoma: can the approach be modified? / Laparoscopia e lavado peritoneal no pré-operatório do adenocarcinoma gástrico: podemos modificar a conduta?

OBJECTIVE: to assess whether laparoscopy with peritoneal lavage is superior to computed tomography for staging gastric adenocarcinoma and whether it can modify the surgical approach. METHODS: we conducted a retrospective study of 46 patients with gastric adenocarcinoma treated by the digestive surgery team of the Passo Fundo Clinics Hospital (RS), from January 2015 to December 2018, and submitted to laparoscopy with preoperative peritoneal lavage. All patients underwent preoperative clinical staging with computed tomography. RESULTS: of the 46 patients analyzed, the majority had tumors located in the cardia (34.8%), poorly differentiated (69.6%), and subtype signet ring cells (65.2%). In 91.3%, the computed tomography scan did not identify peritoneal carcinomatosis or distant metastasis. Among these patients with negative computed tomography for distant disease, 21.8% had positive peritoneal lavage for neoplastic cells and had their therapeutic approaches modified. CONCLUSION: laparoscopy and peritoneal lavage altered the surgical decision in 21.8% of patients, providing a more reliable preoperative staging in gastric adenocarcinoma.

OBJETIVO: avaliar se a laparoscopia com lavado peritoneal é superior à tomografia computadorizada para o estadiamento do adenocarcinoma gástrico e se pode modificar a conduta cirúrgica do paciente. MÉTODOS: estudo retrospectivo de 46 pacientes portadores de adenocarcinoma gástrico tratados pela equipe de cirurgia digestiva do Hospital de Clínicas de Passo Fundo (RS), de janeiro de 2015 a dezembro de 2018, e submetidos à laparoscopia com lavado peritoneal pré-operatório. Todos os pacientes foram submetidos ao estadiamento clínico pré-operatório com tomografia computadorizada. RESULTADOS: dos 46 pacientes analisados, a maioria apresentava tumores localizados na cárdia (34,8%), pouco diferenciados (69,6%) e do subtipo células em anel de sinete (65,2%). Em 91,3% deles a tomografia computadorizada não identificou carcinomatose peritoneal ou metástases à distância. Entre estes pacientes com tomografia computadorizada negativa para doença à distância, 21,8% apresentaram lavado peritoneal positivo para células neoplásicas e tiveram suas condutas terapêuticas modificadas. CONCLUSÃO: a laparoscopia e o lavado peritoneal alteraram a decisão cirúrgica em 21,8% dos pacientes, proporcionando um estadiamento pré-operatório mais fidedigno no adenocarcinoma gástrico.

Right hepatic artery originated from the superior mesenteric artery: What is the standard anatomic position? / Artéria hepática direita originada da artéria mesentérica superior: Qual seu real trajeto anatômico?

OBJECTIVE: Liver arterial irrigation is characterized by a high frequency of variations in its anatomy. The aim of the study was to describe the anatomic position of the right hepatic artery as a brunch of the superior mesenteric artery. METHODS: A total of 5147 intravenous contrast-enhanced computed tomography scans of patients seen at the Radiology Service of the Passo Fundo Clinical Hospital (RS), from October 2016 to December 2017, were selected. 125 patients with anatomic variation of the right hepatic artery were selected. The findings were categorized by the variation of the vascular position, emergence from the superior mesenteric artery and the relationship with other structures. RESULTS: The most frequent position was retropancreatic (88.8%), retroportal (76.8%) and post-choledocian (75.2%), emerging about 2.33 cm from the superior mesenteric artery. CONCLUSION: We have shown that most common variant of the right hepatic artery presents its posterior origin from the pancreatic and hepatic pedicle, and arises close to the origin of the superior mesenteric artery.

OBJETIVOS: A irrigação arterial hepática tem como característica a elevada frequência de variações da anatomia. O objetivo do estudo foi descrever o trajeto anatômico da artéria hepática direita quando originada da artéria mesentérica superior. MÉTODOS: Foram analisadas 5147 tomografias computadorizadas com contraste endovenoso de pacientes atendidos no Serviço de Radiologia do Hospital de Clínicas de Passo Fundo - RS, no período outubro de 2016 a dezembro de 2017. Foram selecionados 125 pacientes portadores de variação anatômica da artéria hepática direita na origem. Os achados foram categorizados pela variação do trajeto vascular, emergência da artéria mesentérica superior e a relação com demais estruturas. RESULTADOS: Obtivemos o trajeto mais frequente desta variação como retropancreático (88,8%), retroportal (76,8%) e pós-coledociano (75,2%), emergindo cerca de 2,33 cm da origem da artéria mesentérica superior. CONCLUSÃO: Demonstramos que na maioria das vezes, a artéria hepática direita variante, apresenta trajeto posterior ao pâncreas e ao pedículo hepático e emerge próxima da origem da artéria mesentérica superior.

Quantitative comparison between the rhizosphere effect of Arabidopsis thaliana and co-occurring plant species with a longer life history.

As a model for genetic studies, Arabidopsis thaliana (Arabidopsis) offers great potential to unravel plant genome-related mechanisms that shape the root microbiome. However, the fugitive life history of this species might have evolved at the expense of investing in capacity to steer an extensive rhizosphere effect. To determine whether the rhizosphere effect of Arabidopsis is different from other plant species that have a less fugitive life history, we compared the root microbiome of Arabidopsis to eight other, later succession plant species from the same habitat. The study included molecular analysis of soil, rhizosphere, and endorhizosphere microbiome both from the field and from a laboratory experiment. Molecular analysis revealed that the rhizosphere effect (as quantified by the number of enriched and depleted bacterial taxa) was ~35% lower than the average of the other eight species. Nevertheless, there are numerous microbial taxa differentially abundant between soil and rhizosphere, and they represent for a large part the rhizosphere effects of the other plants. In the case of fungal taxa, the number of differentially abundant taxa in the Arabidopsis rhizosphere is 10% of the other species' average. In the plant endorhizosphere, which is generally more selective, the rhizosphere effect of Arabidopsis is comparable to other species, both for bacterial and fungal taxa. Taken together, our data imply that the rhizosphere effect of the Arabidopsis is smaller in the rhizosphere, but equal in the endorhizosphere when compared to plant species with a less fugitive life history.

Primary malignant neoplasms of the cecal appendix: unusual findings in acute appendicitis

Introduction: To evaluate the prevalence of appendix neoplasia correlating with patient profile, histological types and frequency. Methods: Data collection was performed in the Pathology Department of a General Hospital, with the objective of identifying patients diagnosed with malignant cecal appendix tumors by histopathologic study of specimens from acute appendicitis. Results: The prevalence of malignant primary epithelial neoplasia of the appendix was 1%. Fifty percent of the cases were neuroendocrine tumors, 35% were mucinous, and 15% were adenocarcinomas. The mean age at diagnosis was 41.3 (SD, 20.4) years (range 16-81), with a women/men ratio of 3:1. Discussion: Appendiceal neoplasms are rare and should be suspected manly in women over 40 years of age with suggestive symptoms of acute appendicitis. The size, location, extent, margins and presence of mucin are essential findings for the treatment of these patients. (AU)

Artéria hepática direita originada da artéria mesentérica superior: Qual seu real trajeto anatômico? / Right hepatic artery originated from the superior mesenteric artery: What is the standard anatomic position?

RESUMO Objetivos: A irrigação arterial hepática tem como característica a elevada frequência de variações da anatomia. O objetivo do estudo foi descrever o trajeto anatômico da artéria hepática direita quando originada da artéria mesentérica superior. Métodos: Foram analisadas 5147 tomografias computadorizadas com contraste endovenoso de pacientes atendidos no Serviço de Radiologia do Hospital de Clínicas de Passo Fundo - RS, no período outubro de 2016 a dezembro de 2017. Foram selecionados 125 pacientes portadores de variação anatômica da artéria hepática direita na origem. Os achados foram categorizados pela variação do trajeto vascular, emergência da artéria mesentérica superior e a relação com demais estruturas. Resultados: Obtivemos o trajeto mais frequente desta variação como retropancreático (88,8%), retroportal (76,8%) e pós-coledociano (75,2%), emergindo cerca de 2,33 cm da origem da artéria mesentérica superior. Conclusão: Demonstramos que na maioria das vezes, a artéria hepática direita variante, apresenta trajeto posterior ao pâncreas e ao pedículo hepático e emerge próxima da origem da artéria mesentérica superior.

ABSTRACT Objective: Liver arterial irrigation is characterized by a high frequency of variations in its anatomy. The aim of the study was to describe the anatomic position of the right hepatic artery as a brunch of the superior mesenteric artery. Methods: A total of 5147 intravenous contrast-enhanced computed tomography scans of patients seen at the Radiology Service of the Passo Fundo Clinical Hospital (RS), from October 2016 to December 2017, were selected. 125 patients with anatomic variation of the right hepatic artery were selected. The findings were categorized by the variation of the vascular position, emergence from the superior mesenteric artery and the relationship with other structures. Results: The most frequent position was retropancreatic (88.8%), retroportal (76.8%) and post-choledocian (75.2%), emerging about 2.33 cm from the superior mesenteric artery. Conclusion: We have shown that most common variant of the right hepatic artery presents its posterior origin from the pancreatic and hepatic pedicle, and arises close to the origin of the superior mesenteric artery.

Laparoscopia e lavado peritoneal no pré-operatório do adenocarcinoma gástrico: podemos modificar a conduta? / Preoperative laparoscopy and peritoneal lavage in gastric adenocarcinoma: can the approach be modified?

RESUMO Objetivo: avaliar se a laparoscopia com lavado peritoneal é superior à tomografia computadorizada para o estadiamento do adenocarcinoma gástrico e se pode modificar a conduta cirúrgica do paciente. Métodos: estudo retrospectivo de 46 pacientes portadores de adenocarcinoma gástrico tratados pela equipe de cirurgia digestiva do Hospital de Clínicas de Passo Fundo (RS), de janeiro de 2015 a dezembro de 2018, e submetidos à laparoscopia com lavado peritoneal pré-operatório. Todos os pacientes foram submetidos ao estadiamento clínico pré-operatório com tomografia computadorizada. Resultados: dos 46 pacientes analisados, a maioria apresentava tumores localizados na cárdia (34,8%), pouco diferenciados (69,6%) e do subtipo células em anel de sinete (65,2%). Em 91,3% deles a tomografia computadorizada não identificou carcinomatose peritoneal ou metástases à distância. Entre estes pacientes com tomografia computadorizada negativa para doença à distância, 21,8% apresentaram lavado peritoneal positivo para células neoplásicas e tiveram suas condutas terapêuticas modificadas. Conclusão: a laparoscopia e o lavado peritoneal alteraram a decisão cirúrgica em 21,8% dos pacientes, proporcionando um estadiamento pré-operatório mais fidedigno no adenocarcinoma gástrico.

ABSTRACT Objective: to assess whether laparoscopy with peritoneal lavage is superior to computed tomography for staging gastric adenocarcinoma and whether it can modify the surgical approach. Methods: we conducted a retrospective study of 46 patients with gastric adenocarcinoma treated by the digestive surgery team of the Passo Fundo Clinics Hospital (RS), from January 2015 to December 2018, and submitted to laparoscopy with preoperative peritoneal lavage. All patients underwent preoperative clinical staging with computed tomography. Results: of the 46 patients analyzed, the majority had tumors located in the cardia (34.8%), poorly differentiated (69.6%), and subtype signet ring cells (65.2%). In 91.3%, the computed tomography scan did not identify peritoneal carcinomatosis or distant metastasis. Among these patients with negative computed tomography for distant disease, 21.8% had positive peritoneal lavage for neoplastic cells and had their therapeutic approaches modified. Conclusion: laparoscopy and peritoneal lavage altered the surgical decision in 21.8% of patients, providing a more reliable preoperative staging in gastric adenocarcinoma.