Burkholderia metalliresistens sp. nov., a multiple metal-resistant and phosphate-solubilising species isolated from heavy metal-polluted soil in Southeast China.

A metal-resistant and phosphate-solubilising bacterium, designated as strain D414(T), was isolated from heavy metal (Pb, Cd, Cu and Zn)-polluted paddy soils at the surrounding area of Dabao Mountain Mine in Southeast China. The minimum inhibitory concentrations of heavy metals for strain D414(T) were 2000 mg L(-1) (Cd), 800 mg L(-1) (Pb), 150 mg L(-1) (Cu) and 2500 mg L(-1) (Zn). The strain possessed plant growth-promoting properties, such as 1-aminocyclopropane-1-carboxylate assimilation, indole production and phosphate solubilisation. Analysis of 16S rRNA gene sequence indicated that the isolate is a member of the genus Burkholderia where strain D414(T) formed a distinct phyletic line with validly described Burkholderia species. Strain D414(T) is closely related to Burkholderia tropica DSM 15359(T), B. bannensis NBRC E25(T) and B. unamae DSM 17197(T), with 98.5, 98.3 and 98.3 % sequence similarities, respectively. Furthermore, less than 34 % DNA-DNA relatedness was detected between strain D414(T) and the type strains of the phylogenetically closest species of Burkholderia. The dominant fatty acids of strain D414(T) were C14:0, C16:0, C17:0 cyclo and C18:1 ω7c. The DNA G+C content was 62.3 ± 0.5 mol%. On the basis of genotypic, phenotypic and phylogenetic data, strain D414(T) represents a novel species, for which the name Burkholderia metalliresistens sp. nov. is proposed, with D414(T) (=CICC 10561(T) = DSM 26823(T)) as the type strain.

Current progress on the endoscopic features of colorectal sessile serrated lesions.

Along with the discovery and refinement of serrated pathways, the World Health Organization amended the classification of digestive system tumors in 2019, recommending the renaming of sessile serrated adenomas/polyps to sessile serrated lesions (SSLs). Given the particularity of the endoscopic appearance of SSLs, it could easily be overlooked and missed in colonoscopy screening, which is crucial for the occurrence of interval colorectal cancer. Existing literature has found that adequate bowel preparation, reasonable withdrawal time, and awareness of colorectal SSLs have improved the quality and accuracy of detection. More particularly, with the continuous advancement and development of endoscopy technology, equipment, and accessories, a potent auxiliary tool is provided for accurate observation and immediate diagnosis of SSLs. High-definition white light endoscopy, chromoendoscopy, and magnifying endoscopy have distinct roles in the detection of colorectal SSLs and are valuable in identifying the size, shape, character, risk degree, and potential malignant tendency. This article delves into the relevant factors influencing the detection rate of colorectal SSLs, reviews its characteristics under various endoscopic techniques, and expects to attract the attention of colonoscopists.

Usefulness of analyzing endoscopic features in identifying the colorectal serrated sessile lesions with and without dysplasia.

BACKGROUND: Sessile serrated lesions (SSLs) are often missed on colonoscopy, and studies have shown this to be an essential cause of interstitial colorectal cancer. The SSLs with dysplasia (SSL-D+), in particular, have a faster rate of carcinogenesis than conventional tubular adenomas. Therefore, there is a clinical need for some endoscopic features with independent diagnostic value for SSL-D+s to assist endoscopists in making immediate diagnoses, thus improving the quality of endoscopic examination and treatment. AIM: To compare the characteristics of SSLs, including those with and without dysplasia (SSL-D+ and SSL-D-), based on white light and image-enhanced endoscopy, to achieve an immediate differential diagnosis for endoscopists. METHODS: From January 2017 to February 2023, cases of colorectal SSLs confirmed by colonoscopy and histopathology at the Gastrointestinal Endoscopy Center of Beijing Tsinghua Changgung Hospital were collected. The general, endoscopic, and histopathological data were reviewed and analyzed to determine the diagnostic utility. Univariate analysis was used to find potential diagnostic factors, and then multivariate regression analysis was performed to derive endoscopic features with independent diagnostic values for the SSL-D+. RESULTS: A total of 228 patients with 253 lesions were collected as a result. There were 225 cases of colorectal SSL-D-s and 28 cases of SSL-D+s. Compared to the colorectal SSL-D-, the SSL-D+ was more common in the right colon (P = 0.027) with complex patterns of depression, nodule, and elevation based on cloud-like surfaces (P = 0.003), reddish (P < 0.001), microvascular varicose (P < 0.001), and mixed type (Pit II, II-O, IIIL, IV) of crypt opening based on Pit II-O (P < 0.001). Multifactorial logistic regression analysis indicated that lesions had a reddish color [odds ratio (OR) = 18.705, 95% confidence interval (CI): 3.684-94.974], microvascular varicose (OR = 6.768, 95%CI: 1.717-26.677), and mixed pattern of crypt opening (OR = 20.704, 95%CI: 2.955-145.086) as the independent predictors for SSL-D+s. CONCLUSION: The endoscopic feature that has independent diagnostic value for SSL-D+ is a reddish color, microvascular varicose, and mixed pattern of crypt openings.

Elevated atmospheric CO2 might increase the health risk of long-term ingestion of leafy vegetables cultivated in residual DDT polluted soil.

Residual dichlorodiphenyltrichloroethane (DDT) in the environment and a continuously increasing atmospheric carbon dioxide (CO2) concentration are two issues that have received a lot of attention. This study was conducted using a pot experiment to investigate the interactive effects of elevated CO2 and DDT on the uptake of DDT, the physiological responses and the resulting health risks in three vegetables. These vegetables included Brassica juncea var. foliosa Bailey (B. Bailey), Brassica campestris L. var. communis Tsen et Lee Suzhou Qing (B. Lee) and Brassica campestris L. ssp. pekinensis (Lour.) Olsson Chun Dawang (B. Olsson). Two levels of CO2 and four DDT treatment levels were set up. Results showed 5 mg kg-1 DDT significantly reduced the shoot biomass of B. Bailey when compared to 0 mg kg-1 DDT treatment under ambient CO2 condition. Elevated CO2 concentration stimulated the growth of B. Bailey and B. Lee, increased the DDT uptake in the shoots of both vegetables and the values of some photosynthesis indices, and triggered the activity of peroxidase and catalase in the shoots when compared to the related ambient CO2 treatment. Elevated CO2 concentration increased the values of hazard indexes for non-carcinogenic and cancer risks of all vegetables when compared to the individual ambient CO2 treatment (each of vegetable has an ambient CO2 treatment), especially for B. Bailey (increase amplitude of 123.81%-127.78% at 5 mg kg-1 DDT). Long-term ingestion with these DDT-polluted vegetables might result in an elevated carcinogenic risk and elevated atmospheric CO2 may enhance the non-carcinogenic and carcinogenic risks.

Ion flux profiles and plant ion homeostasis control under salt stress.

The ability of a plant to maintain an ionic homeostasis is crucial in plant salt tolerance. Direct evidence based on data from the non-invasive measurement of ion fluxes would not only offer new insight about the function of the transporter but also provide a whole plant approach for dissecting salt adaptation mechanisms. Here, we review some reports using the ion-selective microelectrodes to characterize the net ion fluxes of tissues or cells.

Identification of drought tolerance determinants by genetic analysis of root response to drought stress and abscisic Acid.

Drought stress is a common adverse environmental condition that seriously affects crop productivity worldwide. Due to the complexity of drought as a stress signal, deciphering drought tolerance mechanisms has remained a major challenge to plant biologists. To develop new approaches to study plant drought tolerance, we searched for phenotypes conferred by drought stress and identified the inhibition of lateral root development by drought stress as an adaptive response to the stress. This drought response is partly mediated by the phytohormone abscisic acid. Genetic screens using Arabidopsis (Arabidopsis thaliana) were devised, and drought inhibition of lateral root growth (dig) mutants with altered responses to drought or abscisic acid in lateral root development were isolated. Characterization of these dig mutants revealed that they also exhibit altered drought stress tolerance, indicating that this root response to drought stress is intimately linked to drought adaptation of the entire plant and can be used as a trait to access the elusive drought tolerance machinery. Our study also revealed that multiple mechanisms coexist and together contribute to whole-plant drought tolerance.