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1.

Background

The value of apparent diffusion coefficient (ADC) values and quantitative parameters (Ktrans, Kep, Ve) in detecting prognostic factor at 3.0 Tesla remains unclear, especially in predicting prognosis of breast cancer.

Methods

A total of 151 patients with IDC underwent breast DCE-MRI and DWI-MRI at 3.0 Tesla following surgery. The ADC values were acquired with b values of 0 and 1000?s/mm2. The relationship between ADC values or DCE-MRI quantitative parameters and size, histologic grade (HG), lymph node metastasis (LNM), ER, PR, and Ki67 was evaluated. The predictive values of ADC, Ktrans, Kep, and Ve to prognosis of IDC were assessed.

Results

ADC value was positively related to size (P?=?0.04) and HER2 (P?=?0.046) expression and negatively related to ER (P?=?0.012) and PR (P?<?0.001) expression. Ktrans value has positive correlation with size (P?<?0.001), HG (P?<?0.001), LNM (P?<?0.001), HER2 (P?=?0.007), and Ki67 (P?<?0.001) expression and negative correlation with ER (P?<?0.001) and PR (P?<?0.001) expression. Kep value was positively related to size (P?<?0.001) and negatively related to ER (P?<?0.001) and PR (P?<?0.001) expression. Ve value was negatively related to HER2 expression (P?=?0.004). The Cox hazard ratio (HR) of ADC, Ktrans, Kep, and Ve values on survival was 5.26 (P?=?0.093), 1.081 (P?=?0.002), 1.006 (P?=?0.941), and 0.883 (P?=?0.926), respectively.

Conclusions

Ktrans value was a best predictive indicator of HG, LNM, ER, PR, and Ki67 expression, and ADC value was the best predictive indicator of HER2. Preoperative use of the 3.0 Tesla could provide important information to determine the optimal treatment plan.
  相似文献   

2.

Background

The study aimed at examining hypoxia-inducible factor (HIF)1α expression in adenocarcinomas and adenomas in bitches in regard to tumour malignancy grade, proliferation, apoptosis and vascularisation. Therefore, paraffin sections of 15 adenomas and 64 adenocarcinomas sampled from 79 dogs aged 6 to 16 years were analysed.

Results

A significantly higher HIF-1α expression was noted in adenocarcinomas in comparison to adenomas (P?<?0.0004). Moreover, HIF-1α expression in adenocarcinomas correlated positively with tumour malignancy grade (r?=?0.59, P?<?0.05), Ki-67 antigen expression (r?=?0.43; P?<?0.0005), TUNEL-positive cells (r?=?0.62, P?<?0001) and tumour vascularity measured by quantification of vessels characterized by the expression of von Willebrand Factor (r?=?0.57, P?<?0.05).

Conclusion

Results of this study indicate a similar biological role of HIF-1α in dogs and in humans, which may confirm suitability of the animal model in investigations on progression of tumours in humans.
  相似文献   

3.

Background

Regulated in development and DNA damage response (REDD1), a gene responding to hypoxia or multiple DNA damage events, was recently implicated in cancer development and progression. Previously, in vivo and in vitro experiments indicated that REDD1 functions as an oncogene in ovarian cancer cells. However, the role of REDD1 in cancer cell migration and invasion and in clinical significance of prognostic values is not examined in detail.

Methods

We detected the REDD1 protein expression by immunohistochemistry in 18 normal ovarian surface epithelium or fallopian tube epithelium specimens, 24 ovarian borderline tumors, and 229 ovarian cancers. Fisher’s exact test, logistic regression analysis, the Kaplan–Meier method, and the log-rank test were used to evaluate the association of REDD1 with clinical factors, overall survival and disease-free survival. The prognostic predictive value of REDD1 for ovarian cancer patients was evaluated using multivariate Cox proportional hazard regression models. REDD1 expression in HEY, HEY A8, SKOV3, SKOV3 ip1, OVCA429, OVCA433 and A2780 human ovarian epithelial cancer cell lines was detected by western blotting. The role of REDD1 in cell invasion and migration was assessed by transwell migration and invasion assays using SKOV3, A2780, HEY, HEYA8, and SKOV3-REDD1 with parental A2780-REDD1 HEY-REDD1i and HEY A8-REDD1i.

Results

High expression of REDD1 was observed in 35.4% of primary ovarian carcinoma samples. Overexpression of cytoplasmic REDD1 in ovarian cancer was significantly associated with serous carcinoma (P?<?0.001), late-stage disease (P?<?0.001), ascites (P?<?0.001), and partial or non-response to chemotherapy (P?<?0.001). High cytoplasmic expression of REDD1 was correlated with poorer overall survival (P?<?0.001) and disease-free survival (P?<?0.001). The multivariate Cox proportional hazards regression analysis indicated that patients with high cytoplasmic REDD1 expression had a high risk of death (P?<?0.001) and high risk of an event (i.e., recurrence, progression, or death) (P?<?0.001). REDD1 was first reported as an independent prognostic factor in ovarian cancer patients. In addition, REDD1 overexpression enhanced ovarian cancer cell migration and invasion.

Conclusion

REDD1 is an independent unfavorable prognostic factor in ovarian carcinoma and may promote ovarian cancer metastasis.
  相似文献   

4.

Background

Weaning stress affects the small intestine of piglets. MiR-146b is differentially expressed in suckling and weaned piglets. In this study, we evaluated the effects of miR-146b on cell viability, proliferation, and apoptosis in IPEC-J2 cells.

Results

Transfection with miR-146b mimics successfully increased miR-146b levels by 1000× (P?<?0.001). The over-expression of miR-146b significantly promoted the apoptosis (P?<?0.01) of IPEC-J2 cells, with no significant effects on cell viability or proliferation. MiR-146b suppressed the luciferase activity of the miR-TLR4-wt by 57% compared with the negative control, while mutation of the miR-146b binding site significantly blocked the suppressive effect (P?<?0.05). Western blot results showed that TLR4 levels decreased in IPEC-J2 cells transfected with miR-146b mimics (P?<?0.05).

Conclusions

The over-expression of miR-146b promotes IPEC-J2 cell apoptosis. TLR4 is a direct target of miR-146b in IPEC-J2 cells.

Reviewers

This article was reviewed by Eugene Berezikov and Jan B Hoek.
  相似文献   

5.
6.
7.

Background

The aim of this study was to explore the characteristics and prognostic information of estrogen receptor-positive/progesterone receptor-negative (ER+/PR?) male breast cancer.

Methods

Using the US National Cancer Institute’s Surveillance, Epidemiology, and End Results database, we compared the demographics, clinical characteristics, and outcome of estrogen receptor-positive/progesterone receptor-positive (ER+/PR+) patients with ER+/PR? male breast cancer patients from 1990 to 2010. Two thousand three hundred twenty-two patients with ER+/PR+ tumors and 355 patients with ER+/PR? tumors were included in our study.

Results

ER+/PR? patients were younger (P?=?0.008) and more likely to be African American (P?<?0.001) while presented with higher histological grade (P?<?0.001), larger tumor size (P?=?0.010), and more invasion to the lymph nodes (P?=?0.034) and distant sites (P?<?0.001), thus later stage (P?=?0.001). Despite higher chance of receiving chemotherapy (51.0% vs 36.5%, P?<?0.001), ER+/PR? patients experienced significantly worse breast cancer-specific survival (BSCC) (P?<?0.001) and shorter overall survival (OS) (P?=?0.003). Multivariate Cox model confirmed that tumor size, lymph node invasion, metastasis, and surgery were independent prognostic factors of both BSCC and OS for ER+/PR? male breast cancer. Age at diagnosis and chemotherapy were significantly associated with OS but not with BSCC.

Conclusion

ER+/PR? male breast cancer was more aggressive and experienced shorter survival than ER+/PR+ patients. The prognosis was mainly associated with tumor size, lymph node invasion, metastasis, and surgery.
  相似文献   

8.

Background

Acarbose slows down the intestinal absorption of carbohydrates, but its effects on the secretion of incretins are still poorly known. This study aimed to examine the effects of single-dose acarbose on the secretion of incretins in patients with newly diagnosed type 2 diabetes mellitus (T2DM).

Methods

In this pilot study, twenty-three patients diagnosed with T2DM were randomly assigned to the oral glucose tolerance test (OGTT) group (n?=?11) and the mixed meal test (MMT) group (n?=?12). Fourteen subjects with normal OGTT were included as controls. Plasma glucose, insulin, glucagon, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic peptide (GIP) were measured at 0 (fasting), 15, 30, 60, 90, and 120 min after nutrient load. A week later, controls underwent MMT, the OGTT group underwent OGTT receiving 100 mg acarbose, and the MMT group underwent MMT receiving 100 mg acarbose. The same blood markers were measured again.

Results

No significant difference was observed in the OGTT group before and after administering acarbose. In the MMT group, postprandial levels of glucose (P?<?0.01), insulin (P?<?0.01), glucagon at 15 min (P?<?0.05), glucagon area under the curve (AUC) (P?<?0.05), GIP levels at 30 min (P?<?0.05), and GIP AUC (P?<?0.05) were decreased after receiving acarbose with a mixed meal, but GLP-1 levels and GLP-1 AUC did not change.

Conclusions

Single-dose acarbose could reduce the secretion of GIP and glucagon after a mixed meal in patients with newly diagnosed T2DM. The influence of acarbose on incretin levels could be related to the types of carbohydrate being consumed.

Trial registration

This study was registered with the Chinese Clinical Trial Registry (Registration Number: ChiCTR-TRC-14004260, Date of Registration: 2014-01-19).
  相似文献   

9.

Background

Previous research suggested that single gene expression might be correlated with acute myeloid leukemia (AML) survival. Therefore, we conducted a systematical analysis for AML prognostic gene expressions.

Methods

We performed a microarray-based analysis for correlations between gene expression and adult AML overall survival (OS) using datasets GSE12417 and GSE8970. Positive findings were validated in an independent cohort of 50 newly diagnosed, non-acute promyelocytic leukemia (APL) AML patients by quantitative RT-PCR and survival analysis.

Results

Microarray-based analysis suggested that expression of eight genes was each associated with 1-year and 3-year AML OS in both GSE12417 and GSE8970 datasets (p?<?0.05). Next, we validated our findings in an independent cohort of AML samples collected in our hospital. We found that ubiquitin-conjugating enzyme E2E1 (UBE2E1) expression was adversely correlated with AML survival (p?=?0.04). Multivariable analysis showed that UBE2E1 high patients had a significant shorter OS and shorter progression-free survival after adjusting other known prognostic factors (p?=?0.03). At last, we found that UBE2E1 expression was negatively correlated with patients’ response to induction chemotherapy (p?<?0.05).

Conclusions

In summary, we demonstrated that UBE2E1 expression was a novel prognostic factor in adult, non-APL AML patients.
  相似文献   

10.
This study aims to investigate microRNA-195 (miR-195) expression in myocardial ischaemia–reperfusion (I/R) injury and the roles of miR-195 in cardiomyocyte apoptosis though targeting Bcl-2. A mouse model of I/R injury was established. MiR-195 expression levels were detected by real-time quantitative PCR (qPCR), and the cardiomyocyte apoptosis was detected by TUNEL assay. After cardiomyocytes isolated from neonatal rats and transfected with miR-195 mimic or inhibitor, the hypoxia/reoxygenation (H/R) injury model was established. Cardiomyocyte apoptosis and mitochondrial membrane potential were evaluated using flow cytometry. Bcl-2 and Bax mRNA expressions were detected by RT-PCR. Bcl-2, Bax and cytochrome c (Cyt-c) protein levels were determined by Western blot. Caspase-3 and caspase-9 activities were assessed by luciferase assay. Compared with the sham group, miR-195 expression levels and rate of cardiomyocyte apoptosis increased significantly in I/R group (both P<0.05). Compared to H/R + negative control (NC) group, rate of cardiomyocyte apoptosis increased in H/R + miR-195 mimic group while decreased in H/R + miR-195 inhibitor group (both P<0.05). MiR-195 knockdown alleviated the loss of mitochondrial membrane potential (P<0.05). MiR-195 overexpression decreased Bcl-2 mRNA and protein expression, increased BaxmRNA and protein expression, Cyt-c protein expression and caspase-3 and caspase-9 activities (all P<0.05). While, downregulated MiR-195 increased Bcl-2 mRNA and protein expression, decreased Bax mRNA and protein expression, Cyt-c protein expression and caspase-3 and caspase-9 activities (all P<0.05). Our study identified that miR-195 expression was upregulated in myocardial I/R injury, and miR-195 overexpression may promote cardiomyocyte apoptosis by targeting Bcl-2 and inducing mitochondrial apoptotic pathway.  相似文献   

11.
In this study, the effects of orally administrated two native probiotics (Lactobacillus plantarum and Lactobacillus delbrueckii ssp. bulguricus), isolated from the intestine of Shabot fish, Tor grypus, on some immune response parameters and immune-related genes expression against Aeromonas hydrophila in T. grypus were evaluated. Four hundred and eighty juveniles weighing 45?±?10 g were randomly divided into four groups (with three replications) and fed with the experimental diet containing 5?×?107 cfu g?1 of L. plantarum (G1), Lactobacillus bulgaricus (G2), Lactobacillus casei (G3), and a control diet (without probiotics) for 60 continuous days. At the end of the dietary treatments, fish were challenged with a lethal concentration of A. hydrophila (5?×?108 CFU ml?1) via intra peritoneal (i.p) injection. Blood and head kidney samples were taken from six fish in each treatment before challenging and 6, 12, 24, and 48 h and also 7 days after injection. The results showed that lysozyme, complement, bactericidal, and NBT activity of probiotic-treated groups were significantly elevated (P?<?0.05). The IL-8, IL-1β, and TNF-α gene expressions were significantly higher in all probiotic-treated groups (P?<?0.05). Meanwhile, a high direct correlation was observed between serum immune parameters and expression of immune-related genes (P?<?0.0001); furthermore, the highest correlation (R 2?=?0.634, P?<?0.0001) was recorded between IL-1β expression and NBT activity. It can be concluded that not only two native probiotics strains stimulate serum immune responses parameters and immune-related gene expression in T. grypus, but also a high correlation was seen among these indices. The study suggests that gastrointestinal colonization is preferred for host specificity as the strain previously derived from shabot fish displayed better colonization than the non-indigenous bacteria strain such as L. casei. Therefore, these native probiotics bacteria can be accounted as suitable candidates to immune stimulation in fish.  相似文献   

12.
Obesity is a global epidemic characterized not only by excessive fat deposition but also by important complications such as nonalcoholic liver steatosis. Beneficial antiobesogenic effects have been described for some mushrooms. The current study aimed to demonstrate the protective effect of Agaricus bisporus (AB) supplementation against the metabolic alterations induced by high-fat-diet (HFD) feeding. Eight-week-old C57BL/6J mice were fed for 10 weeks with one of the following diets: (1) control diet (n?=?7), (2) HFD (n?=?7), (3) HFD supplemented with 5% AB (n?=?9), and (4) HFD supplemented with 10% AB (n?=?9). A pair-fed group was also included for the 10% AB group (n?=?6). The impact of AB supplementation on food intake, body weight gain, and liver and fat pad weights was examined. Biochemical, histological, and molecular parameters were also analyzed. Dietary supplementation with 10% AB reduced the HFD-induced increase in body, epididymal, and mesenteric fat weights (p?<?0.01, p?<?0.05, and p?<?0.05, respectively). Supplementation with AB also reduced liver damage in a dose-dependent manner (p?<?0.01 and p?<?0.001). This effect was confirmed by histological analysis that showed that liver steatosis was markedly reduced in mice fed with AB. The beneficial properties of 10% AB supplementation appear to be mediated through a decrease in food intake and via stimulation of mesenteric and hepatic free-fatty acid beta-oxidation, along with a decrease in epidydimal and hepatic expression of CD36. In conclusion, supplementation with AB prevents excessive body weight gain and liver steatosis induced by HFD consumption.  相似文献   

13.
Copy number variation (CNV) of DNA sequences, functionally significant but yet fully ascertained, is believed to confer considerable increments in unexplained heritability of quantitative traits. Identification of phenotype-associated CNVs (paCNVs) therefore is a pressing need in CNV studies to speed up their exploitation in cattle breeding programs. Here, we provided a new avenue to achieve this goal that is to project the published CNV data onto meta-quantitative trait loci (meta-QTL) map which connects causal genes with phenotypes. Any CNVs overlapping meta-QTL therefore will be potential paCNVs. This study reported potential paCNVs in Bos taurus autosome 3 (BTA3). Notably, overview indexes and CNVs both highlighted a narrower region (BTA3 54,500,000–55,000,000 bp, named BTA3_INQTL_6) within one constructed meta-QTL. Then, we ascertained guanylate-binding protein 4 (GBP4) among the nine positional candidate genes was significantly associated with adult cattle stature, including body weight (BW, P?<?0.05) and withers height (WHT, P?<?0.05), fitting GBP4 CNV either with three levels or with six levels in the model. Although higher copy number downregulated the mRNA levels of GBP2 (P?<?0.05) and GBP4 (P?<?0.05) in 1-Mb window (54.0–55.0 Mb) in muscle and adipose, additional analyses will be needed to clarify the causality behind the ascertained association.  相似文献   

14.
In order to quantify and characterize the variance in desert riparian forest tree sap flow, we measured the sap flow from Populus euphratica and compared the daytime and nighttime patterns and responses to environmental variables. Results showed that daytime sap flow velocity was significantly higher (P?<?0.05). Daytime and nighttime mean sap flow velocities were 7.65 and 4.01 cm h?1 in spring, 21.38 and 9.60 cm h?1 in summer, and 11.04 and 5.21 cm h?1 in autumn, respectively. Moreover, results indicated that the stoma remained partially open (15% minimum) throughout the night, providing sufficient evidence for the existance of nighttime transpiration. The vapor pressure deficit (VPD), stomatal conductance (Cs), photosynthetically active radiation (PAR), air temperature (Ta), wind speed (WS), and soil moisture (θ) all had significant positive effects on P. euphratica sap flow velocity (P?<?0.05). Furthermore, the relationship between daytime sap flow velocity and VPD showed clockwise hysteresis, while the relationship between nighttime sap flow velocity and VPD showed counter-clockwise hysteresis. It was evident that PAR and VPD were the key factors impacting daytime sap flow velocity, while Cs and θ were the key factors impacting nighttime sap flow velocity. Furthermore, linear regression results showed that daytime sap flow had a significant positive effect on nighttime sap flow throughout the growing season (P?<?0.05).  相似文献   

15.
The aim of this study was to evaluate the anti-apoptosis effects of resveratrol (RSV) on diabetic rats retinal Müller cells in vivo and in vitro and to further investigate the roles of microRNA-29b (miR-29b)/specificity protein 1 (SP1) in the anti-apoptosis mechanism of RSV. Retina was obtained from normal and diabetic rats with or without RSV (5 and 10 mg/kg/day) treatments at 1–7 months. TdT-mediated dUTP-biotin nick end labeling (TUNEL) and Annexin V/PI staining were used to detect apoptosis. Immunofluorescence was used to assess distribution of SP1 in retina. MiR-29b and SP1 messenger RNA (mRNA) expression was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). SP1, Bax, and bcl-2 protein expression was evaluated by western blotting. Caspase-3 activity was detected by assay kit. Our study showed that the TUNEL-positive cells were mainly localized in the inner nuclear layer (INL) of retina and RSV administration effectively suppressed streptozotocin (STZ)-induced apoptosis of retinal cells in INL in vivo (P?<?0.001). Our study also showed that RSV administration effectively suppressed high glucose (HG)-induced retinal Müller cells’ apoptosis in vitro (P?<?0.001). Furthermore, our study revealed that the diabetes-induced downregulated expression of miR-29b and upregulated expression of SP1 could be rescued by RSV in vivo and in vitro (P?<?0.05). The anti-apoptosis effect and downregulated SP1 expression effect of RSV was prevented by miR-29b inhibitor (P?<?0.05). MiR-29b mimic increased the above-mentioned effects of RSV (P?<?0.001). These findings indicate that RSV is a potential therapeutic option for diabetic retinopathy (DR) and that miR-29b/SP1 pathway play roles in the anti-apoptosis mechanism of RSV.  相似文献   

16.

Background

Recently, total pelvic floor reconstruction (TR) has been the treatment of choice for improving urinary incontinence (UI) after radical prostatectomy (RP). However, the superiority of TR with respect to urinary continence recovery following RP remains controversial. This study identified the effect of TR versus nonTR of the pelvic floor on short-term and long-term continence rates after RP.

Methods

A literature search was performed in November 2017 using the PubMed, Embase, and Web of Science databases. Only comparative research or clinical studies reporting urinary continence outcomes was included in the meta-analysis, and the quality of evidence was evaluated using the 2011 Level of Evidence for therapy research.

Results

We analyzed ten studies reporting urinary continence rates after RP at one or more postoperative time points (1, 2, 4, 12, 24, and 52 weeks). TR was associated with significantly better urinary continence outcomes at 1 week (OR 2.76, 95% CI 1.58–4.84, P?<?0.001), 2 weeks (OR 2.57, 95% CI 1.74–3.80, P?<?0.001), 4 weeks (OR 2.61, 95% CI 1.56–4.38, P?<?0.001), 12 weeks (OR 4.33, 95% CI 2.01–9.33, P?<?0.001), 24 weeks (OR 3.83, 95% CI 1.54–9.55, P?=?0.004), 52 weeks (OR 4.10, 95% CI 1.80–9.38, P?<?0.001) after RP. There was no difference in the rate of complications between the two arms (OR 0.54, 95% CI 0.19–1.54, P?=?0.25).

Conclusions

Compared with nonTR, TR is significantly and positively associated with a return to continence but not with complication rate in men following RP, suggesting that TR may be useful for decreasing the urinary incontinence rate after surgery.
  相似文献   

17.
In order to investigate the mechanism of apoptosis in rat intestinal epithelial cells (IEC-6) induced by hydrogen peroxide (H2O2), IEC-6 cells were subjected to 20 μmol/L H2O2 and cell proliferation activity was determined using 3-(4,5-dimethyl-2-yl)-2,5-diphenyltetrazolium bromide. Cell morphology was observed by microscopy and cell apoptosis was detected by acridine orange and ethidium bromide staining and the portion of apoptotic cells was measured by flow cytometry. Genes and proteins related to cell apoptosis were detected by RT-PCR and Western blotting, and the mitochondrial membrane potential was evaluated by fluorescence probes. Results: Significant morphology damage was caused by exposure to H2O2, and results showed that ROS generation significantly increased (P < 0.01). The activity of superoxide dismutase decreased significantly (P < 0.05), malondialdehyde content increased (P < 0.05), and expression of both catalase and glutathione peroxidase decreased significantly (P < 0.05) in the H2O2 treatment group. Mitochondrion membrane potential was reduced, cytochrome released into the cytoplasm and caspase-9 and caspase-3 were significantly increased (P < 0.01) after treatment with H2O2. Moreover, the ratio of Bax/Bcl-2 and apoptosis were significantly increased (P < 0.01) in the H2O2 group. In conclusion, the present study indicated that the mitochondrial pathway plays a vital role in H2O2 induced IEC-6 cell apoptosis.  相似文献   

18.
19.
Studies with diterpenes from marine brown alga Canistrocarpus cervicornis showed the antiviral potential of the products from this alga in controlling the replication of HSV-1 and maintaining low cytotoxicity. Hence, the aim of this work was to evaluate the anti-herpetic efficacy of C. cervicornis extract ointment in BALB/c mice. To test the anti-herpetic efficacy in vivo, four groups of BALB/c mice (n?=?5) were used: 1—untreated, 2—extract ointment (2 % or 0.4 mg cm?2 dose?1), 3—Acyclovir cream (5 % or 1.0 mg cm?2 dose?1), and 4—ointment base. The right midflank of each mouse was clipped and depilated with a chemical depilatory. After 2 days, the skin area was scratched and inoculated with HSV-1. The ointments and cream were applied three times a day over a 16-day period, beginning 1 h after virus inoculation. The development of skin lesions was continuously monitored and scored. To evaluate the effect of C. cervicornis topical treatment on biochemical parameters and on body weight, two uninfected groups were formed: an untreated group and a group treated with ointment C. cervicornis extract (2 %). The signs of infection appeared from the second day after infection, while on the 10th day of the experiment, the ointment base and untreated groups had significantly more severe lesions than did the groups that were treated with extract (p?<?0.05) or acyclovir (p?<?0,01). The topical application of extract ointment did not change body weight, hepatic, or renal function suggesting that the extract has a low toxicity in this route of administration. These results suggest that the extract may be useful in reducing the severity of HSV-1 cutaneous lesions.  相似文献   

20.
Legumes in the genus Adesmia are wild species with forage and medicinal potential. Their nitrogen fixation efficiency depends on their association with soil bacteria known as rhizobia. The aim of this work was to assess the diversity and symbiotic effectiveness of root nodule bacteria from Adesmia boronioides, Adesmia emarginata and Adesmia tenella from different regions of Chile. Adesmia spp. nodules were collected from seven sites obtaining 47 isolates, which resulted in 19 distinct strains. The diversity of the strains was determined via partial sequencing of the dnaK, 16srRNA and nodA genes. The strains were authenticated as root nodule bacteria on their original host and assessed for symbiotic effectiveness on A. emarginata and A. tenella. The strains from Adesmia tenella clustered within the Mesorhizobium clade. Adesmia boronioides nodulated with Mesorhizobium sp., Rhizobium leguminosarum and Bradyrhizobium sp. The rhizobia from A. emarginata were identified as Burkholderia spp, which was symbiotically ineffective on this species and on A. tenella. Strains isolated from Adesmia emarginata nodules, but unable to induce nodulation, were identified as Labrys methylaminiphilus. Labrys strain AG-49 significantly increased root dry weight in A. emarginata. The nodA genes from Adesmia strains were unique and correlated to legume host. A. emarginata was effectively nodulated by Bradyrhizobium AG-64 and A. tenella by Mesorhizobium strains AG-51 and AG.52. It is concluded that Adesmia emarginata, A. tenella and A. boronioides are associated to diverse bacterial symbionts and selection of an effective inoculant is a key step to assist Adesmia spp. adaptation and restoration.  相似文献   

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