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1.
Cell Immunol ; 363: 104317, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33714729

RESUMO

Myeloid derived suppressor cells (MDSCs) can be subset into monocytic (M-), granulocytic (G-) or polymorphonuclear (PMN-), and immature (i-) or early MDSCs and have a role in many disease states. In cancer patients, the frequencies of MDSCs can positively correlate with stage, grade, and survival. Most clinical studies into MDSCs have been undertaken with peripheral blood (PB); however, in the present studies, we uniquely examined MDSCs in the spleens and PB from patients with gastrointestinal cancers. In our studies, MDSCs were rigorously subset using the following markers: Lineage (LIN) (CD3, CD19 and CD56), human leukocyte antigen (HLA)-DR, CD11b, CD14, CD15, CD33, CD34, CD45, and CD16. We observed a significantly higher frequency of PMN- and M-MDSCs in the PB of cancer patients as compared to their spleens. Expression of the T-cell suppressive enzymes arginase (ARG1) and inducible nitric oxide synthase (i-NOS) were higher on all MDSC subsets for both cancer patients PB and spleen cells as compared to MDSCs from the PB of normal donors. Similar findings for the activation markers lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), program death ligand 1 (PD-L1) and program cell death protein 1 (PD-1) were observed. Interestingly, the total MDSC cell number exported to clustering analyses was similar between all sample types; however, clustering analyses of these MDSCs, using these markers, uniquely documented novel subsets of PMN-, M- and i-MDSCs. In summary, we report a comparison of splenic MDSC frequency, subtypes, and functionality in cancer patients to their PB by clustering and cytometric analyses.


Assuntos
Células Supressoras Mieloides/metabolismo , Baço/imunologia , Adulto , Idoso , Arginase/metabolismo , Antígeno B7-H1/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Análise por Conglomerados , Feminino , Citometria de Fluxo/métodos , Neoplasias Gastrointestinais/imunologia , Antígenos HLA-DR/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Células Supressoras Mieloides/citologia , Células Supressoras Mieloides/imunologia , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Receptores Depuradores Classe E/metabolismo , Baço/patologia
2.
Pediatr Transplant ; 25(3): e13915, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33217110

RESUMO

Ingestion of rare-earth magnet beads in children has been a public health concern. The potential risk of swallowing multiple magnets is related to magnet attraction to each other, resulting in serious gastrointestinal complications, such as entero-enteric fistula formation, peritonitis, bowel ischemia or necrosis, bowel perforation, and potentially death. We describe the clinical outcome of a 10-year-old child with a liver-small bowel-pancreas transplant who swallowed 26 rare-earth magnetic beads. The patient presented with fever and abdominal pain. Due to difficulty locating the magnets and post-surgical anatomy changes, only 25 magnets were removed endoscopically. After the procedure, she continued to have abdominal distention and fever, leading to further investigation and subsequently an exploratory laparotomy, which confirmed a walled-off perforation. She was treated conservatively with bowel rest and antibiotics, without the need for small bowel graft resection. She recovered well and was eventually discharged on her home enteral feeding regimen. This case emphasizes the importance of taking a good history and having a high index of suspicion to diagnose this dangerous clinical condition, especially in children with an associated predisposing condition for foreign body ingestion, such as developmental delay. Early diagnosis of multiple magnet bead ingestion and prompt detection of its complications in pediatric intestinal transplant recipients could help initiate appropriate intervention and prevent intestinal graft loss.


Assuntos
Corpos Estranhos/etiologia , Intestino Delgado/transplante , Transplante de Fígado , Imãs , Metais Terras Raras , Transplante de Pâncreas , Complicações Pós-Operatórias/etiologia , Criança , Ingestão de Alimentos , Feminino , Humanos
3.
Transpl Int ; 33(2): 142-148, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31523865

RESUMO

Intestinal transplant recipients experience a high rate of renal complications secondary to dehydration due to increased ostomy output. It is hypothesized that inclusion of donor colon in the intestinal allograft may improve renal function in patients without functional native colon by improving fluid absorption. A single-center retrospective study of intestinal transplant recipients compared outcomes of patients receiving en bloc colon as part an intestinal allograft (ICTx), and those not receiving colon (CCNTx), as well as a control group of intestinal transplant recipients with functional native colon (ITx). Forty-seven patients (ICTx n = 17, CCNTx n = 15, ITx n = 15) were studied. One-year post-transplant renal function, as measured by change in glomerular filtration rate (GFR) and blood urea nitrogen (BUN) from baseline, was superior in ICTx (mean delta-GFR of -1.31 and delta-BUN of -1.46) compared to CCNTx (-6.54 and 17.54, P = 0.05 and P = 0.17, respectively) and similar to the ITx controls (0.55 and 2.09). Recipients of donor colon experienced a higher rate of ileostomy reversal when compared to CCNTx (62.5% vs. 20%, P = 0.0008), which was similar to the ITx controls (60%). These findings support the inclusion of en bloc donor colon in the intestinal allograft for recipients without functional native colon.


Assuntos
Colo/transplante , Intestinos/transplante , Rim/fisiologia , Aloenxertos , Taxa de Filtração Glomerular , Humanos , Ileostomia , Rim/fisiopatologia , Estudos Retrospectivos
4.
Oncology (Williston Park) ; 34(12): 548-552, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33395496

RESUMO

Pancreatic neuroendocrine tumors (NETs) are a heterogeneous group of neoplasms. They can be functioning tumors with secretion of a variety of peptide hormones, or nonfunctioning tumors with metastases to the liver at the time of diagnosis. Well-differentiated tumors tend to be slow-growing and characterized by low tumor mutational burden (TMB) and lower propensity to express PD-L1. Hypercalcemia due to malignancy can occur in about 20% to 30% of patients with cancer. The secretion of parathyroid hormone-related protein (PTH-rP) is among the causes of malignant hypercalcemia and has seldom been associated with hypercalcemia of NETs. Although the therapeutic landscape for neuroendocrine neoplasms has evolved substantially over the past decade, the role of immunotherapy has not yet been completely explored in this group of patients. We present a rare case of a metastatic pancreatic NET with high TMB, high PD-L1 tumor proportion score, and high PTH-rP related hypercalcemia.


Assuntos
Antígeno B7-H1/metabolismo , Hipercalcemia/patologia , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Síndromes Paraneoplásicas/patologia , Feminino , Humanos , Hipercalcemia/complicações , Hipercalcemia/metabolismo , Pessoa de Meia-Idade , Tumores Neuroendócrinos/complicações , Tumores Neuroendócrinos/metabolismo , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/metabolismo , Síndromes Paraneoplásicas/complicações , Síndromes Paraneoplásicas/metabolismo , Prognóstico
5.
Transpl Infect Dis ; 22(2): e13248, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31960531

RESUMO

Intestinal transplant recipients (ITR) are at high risk for infections due to the high level of immunosuppression required to prevent rejection. There are limited data regarding viral enteritis post-intestinal transplantation. We retrospectively reviewed ITR transplanted between January 2008 and December 2016. Descriptive statistics, including mean (standard deviation) and median (range), were performed. Sixty-one (43.9%) of the 139 transplanted patients had viral enteritis: 26% norovirus, 25% adenovirus, and 9% each rotavirus and sapovirus. The median age of pediatric patients was 1.6 years (0.4-16.9) and for adults 36.3 years (27.1-48.2). Fifty-seven (58%) of 99 pediatric ITR had viral enteritis compared to 4 (10%) of 40 adult ITR. Median time-to-clinical resolution of enteritis for all patients was 5 days (1-92). Standard of care therapies administered: anti-motility agents (10%), anti-emetics agents (14%), and intravenous fluids (42%). There was a higher incidence of viral enteritis in pediatric compared to adults ITR. The majority of viral enteritis episodes resolved within 1 week and were treated with supportive therapy.


Assuntos
Enterite/virologia , Intestinos/transplante , Intestinos/virologia , Transplantados/estatística & dados numéricos , Viroses/diagnóstico , Adolescente , Adulto , Criança , Pré-Escolar , Enterite/terapia , Feminino , Humanos , Terapia de Imunossupressão/efeitos adversos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Viroses/terapia , Adulto Jovem
6.
Int J Syst Evol Microbiol ; 69(8): 2312-2314, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31120414

RESUMO

The genus Ochrobactrum belongs to the family Brucellaceae and its members are known to be adapted to a wide range of ecological niches. Ochrobactrum anthropi ATCC 49188T and Ochrobactrum lupini LUP21T are strains isolated from human clinical and plant root nodule samples, respectively, which share high similarity for phylogenetic markers (i.e 100 % for 16S rRNA, 99.9 % for dnaK and 99.35 % for rpoB). In this work, multiple genome average nucleotide identity (ANI) approaches, digital DNA-DNA hybridization (dDDH) and phylogenetic analysis were performed in order to investigate the taxonomic relationship between O. anthropi ATCC 49188T, O. lupini LUP21T, and other five type strains from the genus Ochrobactrum. Whole-genome comparisons demonstrated that O. lupini LUP21T and the Ochrobactrum genus type species, O. anthropi ATCC 49188T, share 97.55 % of ANIb, 98.25 % of ANIm, 97.99 % of gANI, 97.94 % of OrthoANI and 83.9 % of dDDH, which exceed the species delineation thresholds. These strains are also closely related in phylogenies reconstructed from a concatenation of 1193 sequences from single-copy ortholog genes. A review of their profiles revealed that O. anthropi ATCC 49188T and O. lupini LUP21T do not present pronounced differences at phenotypic and chemotaxonomic levels. Considering phylogenetic, genomic, phenotypic and chemotaxonomic data, O. lupini should be considered a later heterotypic synonym of O. anthropi.


Assuntos
Ochrobactrum anthropi/classificação , Ochrobactrum/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Humanos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Clin Transplant ; 33(11): e13713, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31532002

RESUMO

Open abdomen and fascial dehiscence after intestinal transplantation increase morbidity. This study aims to identify recipient and donor factors associated with failure to achieve sustained primary closure (failed-SPC) of the abdomen after intestinal transplant. We conducted a single-center retrospective study of 96 intestinal transplants between 2013 and 2018. Thirty-eight (40%) were adult patients, and 58 were pediatric patients. Median age at transplantation was 36.0 and 5.8 years, respectively. Failed-SPC occurred in 31 (32%) patients. Identified risk factors of failed-SPC included preexisting enterocutaneous fistula (OR: 6.8, CI: 2.4-19.6, P = .0003), isolated intestinal graft (OR: 3.4, CI: 1.24-9.47, P = .02), male sex in adults (OR: 3.93, CI: 1.43-10.8, P = .009), and age over four years (OR: 6.22, CI: 1.7-22.7, P = .004). There was no association with primary diagnosis and prior transplant with failed-SPC. Donor-to-recipient size ratios did not predict failed-SPC. There was an association between failed-SPC and extended median hospital stay (100 vs 57 days, P = .007) and increased time to enteral autonomy in pediatric patients. There is a relationship between failed-SPC and a higher rate of laparotomy (OR: 21.4, CI: 2.78-178.2, P = .0003) and fistula formation posttransplant (OR: 11.4, CI: 2.83-45.84, P = .0005) in pediatric patients. Given inferior outcomes with failed-SPC, high-risk recipients require careful evaluation.


Assuntos
Parede Abdominal/cirurgia , Rejeição de Enxerto/mortalidade , Hérnia Abdominal/mortalidade , Intestinos/transplante , Transplante de Órgãos/mortalidade , Complicações Pós-Operatórias/mortalidade , Parede Abdominal/fisiopatologia , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Hérnia Abdominal/etiologia , Hérnia Abdominal/patologia , Humanos , Masculino , Transplante de Órgãos/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
8.
Oncology (Williston Park) ; 33(9)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31571182

RESUMO

Biliary cancer is a highly aggressive malignancy arising from the biliary tree, with its incidence increasing steadily on a global level. Most biliary cancers are diagnosed in the advanced and metastatic stages due to the paucity of signs and symptoms in the early presentation. Only about one-third of the patients can be treated with curative intent with an overall median survival of less than 24 months for all-comers from the time of diagnosis. This fact and the poor results of the currently available local and systemic therapies, are responsible for the disappointing outcome of biliary cancer patients. There is an unmet need for novel therapeutic approaches. Surgery, the backbone of curative treatments for biliary cancer, is effective in early, completely-resectable stages or in combination with neoadjuvant or adjuvant chemotherapy and/or radiation therapy for locally advanced stages. Systemic therapies in unresectable and recurrent cases are associated with poor outcomes. The introduction of next-generation sequencing technologies has opened new horizons for a better understanding of the molecular basis of this cancer with potential identification and evaluation of new treatment options.


Assuntos
Neoplasias do Sistema Biliar/terapia , Neoplasias do Sistema Biliar/diagnóstico , Terapia Combinada , Previsões , Humanos , Prognóstico
9.
Pediatr Transplant ; 22(3): e13165, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29441651

RESUMO

Children undergoing LSBPTx are at increased risk of IPI due to splenectomy. We aimed to describe the clinical features and outcomes of IPI in pediatric LSBPTx recipients. Between 2008 and 2016, 122 LSBPTx children at our center were retrospectively reviewed. Nine patients had 12 episodes of IPI; the median age at first infection was 3.5 years (range: 1.5-7.1 years). The median time from transplant to first infection was 3 years (range: 0.8-5.8 years). Clinical presentation included as follows: pneumonia (n = 1), bacteremia/sepsis (n = 7), pneumonia with sepsis (n = 1), meningitis with sepsis (n = 2), pneumonia and meningitis with sepsis (n = 1). The overall risk for IPI was 7.4% or 0.9% per year. The mortality rate was 22%. Seven (78%) children had received at least one dose of PCV13, four (44%) patients had received 23-valent pneumococcal polysaccharide vaccine prior to IPI. All patients were on oral penicillin prophylaxis. In conclusion, despite partial or complete pneumococcal immunization and reported antimicrobial prophylaxis, IPI in LSBPTx children can have a fatal outcome. Routine monitoring of pneumococcal serotype antibodies to determine the timing for revaccination might be warranted to ensure protective immunity in these transplant recipients.


Assuntos
Intestino Delgado/transplante , Transplante de Fígado , Transplante de Pâncreas , Infecções Pneumocócicas/diagnóstico , Infecções Pneumocócicas/etiologia , Complicações Pós-Operatórias/diagnóstico , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/terapia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Esplenectomia , Resultado do Tratamento
10.
Genet Mol Biol ; 41(2): 502-506, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29782030

RESUMO

Lupinus albescens is a resistant cover plant that establishes symbiotic relationships with bacteria belonging to the Bradyrhizobium genus. This symbiosis helps the development of these plants in adverse environmental conditions, such as the ones found in arenized areas of Southern Brazil. This work studied three Bradyrhizobium sp. (AS23, NAS80 and NAS96) isolated from L. albescens plants that grow in extremely poor soils (arenized areas and adjacent grasslands). The genomes of these three strains were sequenced in the Ion Torrent platform using the IonXpress library preparation kit, and presented a total number of bases of 1,230,460,823 for AS23, 1,320,104,022 for NAS80, and 1,236,105,093 for NAS96. The genome comparison with closest strains Bradyrhizobium japonicum USDA6 and Bradyrhizobium diazoefficiens USDA110 showed important variable regions (with less than 80% of similarity). Genes encoding for factors for resistance/tolerance to heavy metal, flagellar motility, response to osmotic and oxidative stresses, heat shock proteins (present only in the three sequenced genomes) could be responsible for the ability of these microorganisms to survive in inhospitable environments. Knowledge about these genomes will provide a foundation for future development of an inoculant bioproduct that should optimize the recovery of degraded soils using cover crops.

12.
Genet Mol Biol ; 39(1): 111-21, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27007904

RESUMO

In the pursuit of sustainable agriculture, bioinoculants usage as providers of a crop's needs is a method to limit environmental damage. In this study, a collection of cultivable putative plant growth promoting (PGP) bacteria associated with wheat crops was obtained and this bacterial sample was characterized in relation to the functional diversity of certain PGP features. The isolates were obtained through classical cultivation methods, identified by partial 16S rRNA gene sequencing and characterized for PGP traits of interest. Functional diversity characterization was performed using Categorical Principal Component Analysis (CatPCA) and Multiple Correspondence Analysis (MCA). The most abundant genera found among the 346 isolates were Pseudomonas, Burkholderia, and Enterobacter. Occurrence of PGP traits was affected by genus, niche, and sampling site. A large number of genera grouped together with the ability to produce indolic compounds; phosphate solubilization and siderophores production formed a second group related to fewer genera, in which the genus Burkholderia has a great importance. The results obtained may help future studies aiming prospection of putative plant growth promoting bacteria regarding the desired organism and PGP trait.

13.
Clin Infect Dis ; 60(2): 216-22, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25301215

RESUMO

BACKGROUND: Sepsis is a serious complication of solid organ transplant (SOT). Evidence on survival differences between SOT recipients and non-SOT patients with sepsis is lacking. METHODS: This was a matched, case-control propensity-adjusted study. Conditional logistic regression was performed for risk factor analysis, and Cox proportional hazards regression for survival analysis. RESULTS: Three hundred sixty-nine patients (123 cases; 246 controls) diagnosed with blood culture-proven sepsis were matched 1:2 by age, sex, and hospital location. The distribution of allografts was 36.6% kidney, 34.1% liver, 13% kidney-pancreas, 7.3% small bowel/liver, 5.7% heart/lung, and 3.3% multivisceral. The conditional logistic regression showed that the following factors were significantly more frequently associated with SOT compared to non-SOT: higher number of comorbidities (odds ratio [OR] = 8.2 [95% confidence interval {CI}, 1.48-45.44], P = .016); higher Sepsis-related Organ Failure Assessment score (OR = 1.2 [95% CI, 1.07-1.32], P = .001); presence of nosocomial infection (OR = 36.3 [95% CI, 9.71-135.96], P < .0001); appropriate initial antibiotics (OR = 0.04 [95% CI, .006-.23], P < .0001); and lower white blood cell count (OR = 0.93 [95% CI, .89-.97], P < .0001). Cox proportional hazards regression showed that after all adjustments for clinical presentation, severity of illness, and types of infection, SOT recipients with sepsis had a significantly lower risk of death at 28 days (hazard ratio [HR] = 0.22 [95% CI, .09-.54], P = .001) and at 90 days (HR = 0.43 [95% CI, .20-.89], P = .025). CONCLUSIONS: The 28-day and 90-day mortality were significantly decreased for transplant recipients compared with nontransplant patients. These findings suggest that the immunosuppression associated with transplantation may provide a survival advantage to transplant recipients with sepsis through modulation of the inflammatory response.


Assuntos
Bacteriemia/mortalidade , Transplantados , Estudos de Casos e Controles , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento
14.
Genet Mol Biol ; 38(2): 205-12, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26273224

RESUMO

The aim of this study was to evaluate the impact of different grazing pressures on the activity and diversity of soil bacteria. We performed a long-term experiment in Eldorado do Sul, southern Brazil, that assessed three levels of grazing pressure: high pressure (HP), with 4% herbage allowance (HA), moderate pressure (MP), with 12% HA, and low pressure (LP), with 16% HA. Two reference areas were also assessed, one of never-grazed native vegetation (NG) and another of regenerated vegetation after two years of grazing (RG). Soil samples were evaluated for microbial biomass and enzymatic (ß-glucosidase, arylsulfatase and urease) activities. The structure of the bacterial community and the population of diazotrophic bacteria were evaluated by RFLP of the 16S rRNA and nifH genes, respectively. The diversity of diazotrophic bacteria was assessed by partial sequencing of the 16S rDNA gene. The presence of grazing animals increased soil microbial biomass in MP and HP. The structures of the bacterial community and the populations of diazotrophic bacteria were altered by the different grazing managements, with a greater diversity of diazotrophic bacteria in the LP treatment. Based on the characteristics evaluated, the MP treatment was the most appropriate for animal production and conservation of the Pampa biome.

15.
J Pediatr ; 164(1): 93-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24094877

RESUMO

OBJECTIVE: To analyze the effects of serial transverse enteroplasty (STEP) on parenteral and enteral calories in children with short bowel syndrome, and examine short- and long-term complications. STUDY DESIGN: A retrospective analysis of prospectively-collected data from a large single center cohort of patients undergoing STEP procedure was analyzed. Baseline demographic and clinical information, operative data, and short- and long-term complications were recorded. Detailed growth and nutritional data were obtained for 6 months prior and 12 months following STEP procedure. RESULTS: Sixty-eight procedures were performed in 51 patients over a 68-month period. Median bowel length at first STEP was 51 cm with a median length gain of 54%. Repeat STEP patients had longer initial length (77 cm) and reduced length gain (20%). Operative times and blood loss were low, with few complications. Parenteral calorie requirement was stable or rising for 6 months prior to STEP, but decreased to median <20 kCal/kg/d at 1 year postop. Longer length gains were associated with higher risk of stricture formation. Seven children were transplanted, and 60% of nontransplanted children were enterally independent, with the remainder making ongoing progress; 48/51 children are alive at a median of 39 months follow-up. CONCLUSIONS: STEP is shown to be safe, well tolerated, and to have definitive benefit in reducing parenteral calorie requirements over the first year following the procedure. It has an important role in achieving enteral independence in children with short bowel syndrome.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Ingestão de Energia , Nutrição Parenteral/métodos , Procedimentos de Cirurgia Plástica/métodos , Síndrome do Intestino Curto/terapia , Desmame , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Período Pós-Operatório , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
17.
Genet Mol Biol ; 37(2): 396-405, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25071405

RESUMO

This work aimed to evaluate the symbiotic compatibility and nodulation efficiency of rhizobia isolated from Desmodium incanum, Lotus corniculatus, L. subbiflorus, L. uliginosus and L. glaber plants by cross-inoculation. Twelve reference strains and 21 native isolates of rhizobia were genetically analyzed by the BOX-PCR technique, which showed a high genetic diversity among the rhizobia studied. The isolates were also characterized based on their production of indolic compounds and siderophores, as well as on their tolerance to salinity. Fifteen of the 33 rhizobia analyzed were able to produce indolic compounds, whereas 13 produced siderophores. All the tested rhizobia were sensitive to high salinity, although some were able to grow in solutions of up to 2% NaCl. Most of the native rhizobia isolated from L. uliginosus were able to induce nodulation in all plant species studied. In a greenhouse experiment using both D. incanum and L. corniculatus plants, the rhizobia isolate UFRGS Lu2 promoted the greatest plant growth. The results demonstrate that there are native rhizobia in the soils of southern Brazil that have low host specificity and are able to induce nodulation and form active nodules in several plant species.

18.
Microb Ecol ; 65(3): 593-601, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23064947

RESUMO

Crop production may benefit from plant growth-promoting bacteria. The knowledge on bacterial communities is indispensable in agricultural systems that intend to apply beneficial bacteria to improve plant health and production of crops such as canola. In this work, the diversity of root bacterial communities associated to two different developmental phases of canola (Brassica napus L.) plants was assessed through the application of new generation sequencing technology. Total bacterial DNA was extracted from root samples from two different growth states of canola (rosette and flowering). It could be shown how bacterial communities inside the roots changed with the growing stage of the canola plants. There were differences in the abundance of the genera, family, and even the phyla identified for each sample. While in both root samples Proteobacteria was the most common phylum, at the rosette stage, the most common bacteria belonged to the family Pseudomonadaceae and the genus Pseudomonas, and in the flowering stage, the Xanthomonadaceae family and the genus Xanthomonas dominated the community. This implies in a switch in the predominant bacteria in the different developmental stages of the plant, suggesting that the plant itself interferes with the associated microbial community.


Assuntos
Bactérias/isolamento & purificação , Brassica napus/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Técnicas de Tipagem Bacteriana , Biodiversidade , Brassica napus/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Dados de Sequência Molecular , Filogenia , Raízes de Plantas/crescimento & desenvolvimento
19.
Braz J Microbiol ; 54(1): 335-348, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36357769

RESUMO

Black wattle (Acacia mearnsii) is a forest species of significant economic importance in southern Brazil; as a legume, it forms symbiotic associations with rhizobia, fixing atmospheric nitrogen. Nonetheless, little is known about native rhizobia in soils where the species is cultivated. Therefore, this study aimed to evaluate the diversity and symbiotic efficiency of rhizobia nodulating A. mearnsii in commercial planting areas and validate the efficiency of a potential strain in promoting seedling development. To this end, nodules were collected from four A. mearnsii commercial plantations located in Rio Grande do Sul State, southern Brazil. A total of 80 rhizobia isolates were obtained from black wattle nodules, and thirteen clusters were obtained by rep-PCR. Higher genetic diversity was found within the rhizobial populations from the Duas Figueiras (H' = 2.224) and Seival (H' = 2.112) plantations. Twelve isolates were evaluated belonging to the genus Bradyrhizobium, especially to the species Bradyrhizobium guangdongense. The principal component analysis indicated an association between rhizobia diversity and the content of clay, Ca, Mg, and K. Isolates and reference strains (SEMIA 6163 and 6164) induced nodulation and fixed N via symbiosis with black wattle plants after 60 days of germination. The isolates DF2.4, DF2.3, DF3.3, SEMIA 6164, SEMIA 6163, CA4.3, OV3.4, and OV1.4 showed shoot nitrogen accumulation values similar to the N + control treatment. In the second experiment (under nursery conditions), inoculation with the reference strain SEMIA 6164 generally improved the growth of A. mearnsii seedlings, reinforcing its efficiency even under production conditions.


Assuntos
Acacia , Bradyrhizobium , Rhizobium , Rhizobium/genética , Plântula , Fixação de Nitrogênio , Simbiose/genética , Filogenia , Nódulos Radiculares de Plantas/microbiologia , Bradyrhizobium/genética
20.
Am J Surg ; 224(5): 1285-1288, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35787911

RESUMO

BACKGROUND: Previous cholecystectomy is common in patients with short bowel syndrome (SBS). An intact gallbladder is beneficial in preventing cirrhosis in SBS patients, but the nutritional consequences of cholecystectomy are largely unknown. Our aim was to evaluate the effect of pre-SBS cholecystectomy on need for chronic parenteral nutrition (PN). METHODS: We reviewed 485 adults with SBS: 267 underwent cholecystectomy prior to SBS and 218 patients had an intact gallbladder. Demographic data, intestinal anatomy, and nutritional outcome were compared. RESULTS: Pre-SBS cholecystectomy patients were more likely to have had postoperative SBS and BMI >35. Intestinal remnant length and anatomy type and performance of surgical rehabilitation procedures within the first year were similar. Overall, there was no significant difference in the need for PN > 1year between the two groups. There was also no significant difference in the need for PN > 1year in any specific subgroup of intestinal remnant length or intestinal anatomy. CONCLUSIONS: Cholecystectomy performed prior to the development of SBS does not influence the nutritional prognosis of SBS, regardless of the intestinal remnant length and anatomy type.


Assuntos
Síndrome do Intestino Curto , Adulto , Humanos , Síndrome do Intestino Curto/cirurgia , Nutrição Parenteral , Colecistectomia , Intestinos , Prognóstico , Estudos Retrospectivos
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