pH-based ecological coherence of active canonical methanotrophs in paddy soils

Abstract. Soil pH is considered one of the main determinants of the assembly of globally distributed microorganisms that catalyse the biogeochemical cycles of carbon and nitrogen. However, direct evidence for niche specialization of microorganisms in association with soil pH is still lacking. Using methane-oxidizing bacteria (methanotrophs) as a model system of carbon cycling, we show that pH is potentially the key driving force selecting for canonical gamma- (type I) and alpha- (type II) methanotrophs in rice paddy soils. DNA-based stable isotope probing (DNA-SIP) was combined with high-throughput sequencing to identify the taxonomic identities of active methanotrophs in physiochemically contrasting soils from 6 different paddy fields across China. Following microcosm amendment with 13CH4, methane was primarily consumed by Methylocystis-affiliated type II methanotrophs in soils with a relatively low pH (5.44–6.10), whereas Methylobacter/Methylosarcina-affiliated type I methanotrophs dominated methane consumption in soils with a high pH (7.02–8.02). Consumption of 13CH4 contributed 0.203 % to 1.25 % of soil organic carbon, but no significant difference was observed between high-pH and low-pH soils. The fertilization of ammonium nitrate resulted in no significant changes in the compositions of 13C-labelled methanotrophs in the soils, although significant inhibition of methane oxidation activity was consistently observed in low-pH soils. Mantel analysis further validated soil pH, rather than other parameters tested, had significant correlation to the variation of active methanotrophic compositions across different rice paddy soils. These results suggest that soil pH might have played pivotal roles in mediating the niche differentiation of ecologically important aerobic methanotrophs in terrestrial ecosystems and imply the importance of such niche specialization in regulating methane emissions in paddy field under increasingly intensified input of anthropogenic N fertilizers.

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The pH-based ecological coherence of active canonical methanotrophs in paddy soils

Biogeosciences ◽

10.5194/bg-17-1451-2020 ◽

2020 ◽

Vol 17 (6) ◽

pp. 1451-1462 ◽

Cited By ~ 3

Author(s):

Jun Zhao ◽

Yuanfeng Cai ◽

Zhongjun Jia

Keyword(s):

Soil Ph ◽

Rice Paddy ◽

Low Ph ◽

Paddy Soils ◽

Paddy Fields ◽

Type I ◽

Type Ii ◽

High Ph ◽

Niche Specialization ◽

Rice Paddy Soils

Abstract. Soil pH is considered one of the main determinants of the assembly of globally distributed microorganisms that catalyze the biogeochemical cycles of carbon (C) and nitrogen (N). However, direct evidence for niche specialization of microorganisms in association with soil pH is still lacking. Using methane-oxidizing bacteria (methanotrophs) as a model system of C cycling, we show that pH is potentially the key driving force selecting for canonical γ (type I) and α (type II) methanotrophs in rice paddy soils. DNA-based stable isotope probing (DNA-SIP) was combined with high-throughput sequencing to reveal the taxonomic identities of active methanotrophs in physiochemically contrasting soils from six different paddy fields across China. Following microcosm incubation amended with 13CH4, methane was primarily consumed by Methylocystis-affiliated type II methanotrophs in soils with a relatively low pH (5.44–6.10), whereas Methylobacter- or Methylosarcina-affiliated type I methanotrophs dominated methane consumption in soils with a high pH (7.02–8.02). Consumption of 13CH4 contributed 0.203 % to 1.25 % of soil organic C, but no significant difference was observed between high-pH and low-pH soils. The fertilization of ammonium nitrate resulted in no significant changes in the compositions of 13C-labeled methanotrophs in the soils, although significant inhibition of methane oxidation activity was consistently observed in low-pH soils. Mantel analysis further validated that soil pH, rather than other parameters tested, had significant correlation to the variation in active methanotrophic compositions across different rice paddy soils. These results suggest that soil pH might have played a pivotal role in mediating the niche differentiation of ecologically important aerobic methanotrophs in terrestrial ecosystems and imply the importance of such niche specialization in regulating methane emissions in paddy fields following increasingly intensified input of anthropogenic N fertilizers.

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Analysis of sagittal profile and radiographic parameters in symptomatic thoracolumbar disc herniation patients

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04033-x ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Ang Gao ◽

Yongqiang Wang ◽

Miao Yu ◽

Xiaoguang Liu

Keyword(s):

Disc Herniation ◽

Thoracic Spine ◽

Normal Population ◽

Sagittal Profile ◽

Sacral Slope ◽

Type I ◽

Type Ii ◽

Radiographic Parameters ◽

Significant Difference ◽

Thoracolumbar Region

Abstract Background Few studies describe thoracolumbar disc herniation (TLDH) as an isolated category, it is frequently classified as the lower thoracic spine or upper lumbar spine. Thus, less is known about the morphology and aetiology of TLDH compared to lumbar disc herniation (LDH). The aim of study is to investigate sagittal alignment in TLDH and analyze sagittal profile with radiographic parameters. Methods Data from 70 patients diagnosed with TLDH were retrospectively reviewed. The thoracic-lumbar alignment was depicted by description of curvatures (the apex of lumbar curvature, the apex of thoracic curvature, and inflexion point of the two curvatures) and radiographic parameters from complete standing long-cassette spine radiographs. The rank sum test was utilised to compare radiographic parameter values in each subtype. Results We found two subtypes differentiated by the apex of thoracic kyphotic curves. The sagittal profile was similar to that of the normal population in type I, presenting the apex of the thoracic kyphotic curve located in the middle thoracic spine. The well aligned thoracic-lumbar curve was disrupted in type II, presenting the apex of the thoracic kyphotic curve located in the thoracolumbar region in type II patients. Thirty-six patients were classified as type I, and 34 patients were classified as type II. The mean sagittal vertical axis, T1 pelvic angle and L1 pelvic angle were 27.9 ± 24.8°, 8.2 ± 7.3° and 6.2 ± 4.9°, respectively. There was significant difference (p < 0.001) of thoracolumbar angle between type I (14.9 ± 7.9°) and type II patients (29.1 ± 13.7°). Conclusions We presented two distinctive sagittal profiles in TLDH patients, and a regional kyphotic deformity with a balanced spine was validated in both subtypes. In type I patients, disc degeneration was accelerated by regional kyphosis in the thoracolumbar junction and eventually caused disc herniation. In type II patients, excessive mechanical stress was directly loaded at the top of the curve (thoracolumbar apex region) rather than being diverted by an arc as in a normal population or type I patients. Mismatch between shape and sacral slope value was observed, and better agreement was found in Type II patients.

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High-throughput sequencing analysis of microbial community diversity in response to indica and japonica bar-transgenic rice paddy soils

PLoS ONE ◽

10.1371/journal.pone.0222191 ◽

2019 ◽

Vol 14 (9) ◽

pp. e0222191 ◽

Cited By ~ 1

Author(s):

Meidan He ◽

Jiachao Zhang ◽

Linbo Shen ◽

Lixin Xu ◽

Wenjie Luo ◽

...

Keyword(s):

Microbial Community ◽

Transgenic Rice ◽

High Throughput ◽

High Throughput Sequencing ◽

Rice Paddy ◽

Paddy Soils ◽

Community Diversity ◽

Sequencing Analysis ◽

Microbial Community Diversity ◽

Rice Paddy Soils

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Abundance of Methanogens, Methanotrophic Bacteria, and Denitrifiers in Rice Paddy Soils

Wetlands ◽

10.1007/s13157-013-0477-y ◽

2013 ◽

Vol 34 (2) ◽

pp. 213-223 ◽

Cited By ~ 11

Author(s):

Juyoung Seo ◽

Inyoung Jang ◽

Gerhard Gebauer ◽

Hojeong Kang

Keyword(s):

Rice Paddy ◽

Paddy Soils ◽

Methanotrophic Bacteria ◽

Rice Paddy Soils

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Microbial community structure with trends in methylation gene diversity and abundance in mercury-contaminated rice paddy soils in Guizhou, China

Environmental Science Processes & Impacts ◽

10.1039/c7em00558j ◽

2018 ◽

Vol 20 (4) ◽

pp. 673-685 ◽

Cited By ~ 13

Author(s):

Tatiana A. Vishnivetskaya ◽

Haiyan Hu ◽

Joy D. Van Nostrand ◽

Ann M. Wymore ◽

Xiaohang Xu ◽

...

Keyword(s):

Community Structure ◽

Microbial Community ◽

Microbial Community Structure ◽

Gene Diversity ◽

Rice Paddy ◽

Paddy Soils ◽

Rice Paddies ◽

Sulfate Reducing ◽

Rice Paddy Soils ◽

Reducing Bacteria

Sulfate-reducing bacteria and methanogens are the primary Hg-methylators in Chinese rice paddies.

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RA05.04: MANAGEMENT & OUTCOMES OF ANASTOMOTIC LEAKS FOLLOWING ESOPHAGECTOMY: A PROSPECTIVE 10-YEAR SINGLE-SITE EXPERIENCE

Diseases of the Esophagus ◽

10.1093/dote/doy089.ra05.04 ◽

2018 ◽

Vol 31 (Supplement_1) ◽

pp. 28-28

Author(s):

Joel Lambert ◽

Sanya Caratella ◽

Eloise Lawrence ◽

Bilal Alkhaffaf

Keyword(s):

Minimally Invasive ◽

Anastomotic Leak ◽

Surgical Intervention ◽

Type I ◽

Oral Contrast ◽

Open Approach ◽

Type Ii ◽

Anastomotic Leaks ◽

Type Iii ◽

Significant Difference

Abstract Background Anastomotic leak after esophagectomy is associated with high levels of morbidity and may impact negatively on oncological outcomes. The aim of this single centre study was to describe our experience in managing these complications Methods From 2007–2017 data was reviewed retrospectively from our prospectively maintained electronic database. All patients underwent either 2 or 3 phase esophagectomy for cancer of the oesophagus or esophago-gastric junction. All histological sub-types and stage of cancer were included in the analysis. Anastomotic leaks were classified according to the Esophagectomy Complications Consensus Group (ECCG) guidelines; type I—conservative management, type II—non-surgical intervention, type III—surgical intervention. Results 224 esophagectomies were included in our analysis (104 (46%) minimally invasive, 120 (54%) open approach). The incidence of all anastomotic leaks was 10% (23/224). Surgical approach did not influence the incidence of anastomotic leak (minimally invasive 10 (43%), open approach 13(57%), P = 0.76). Five patients (22%) had a type I leak, 9 patients (39%) type II and 9 (39%) had a type III leak. There was an increase in the number of leaks managed non-surgically over the last 5 years compared to those in the first five years of our dataset (2012–2017: 11/23 (48%) vs 2007–2012: 4/23 (17%) P = 0.08). The median time for leak diagnosis was 8 days. Most leaks were diagnosed with oral contrast CT 19 (83%). Median hospital stay after anastomotic leak was 58.5 days. Type III leaks were associated with an increased length of stay (median 84 days) compared to type I&II leaks (median (38.5 days) (P = 0.002 95% CI 18.19- 74.41). There was no significant difference in 30-day mortality between type I&II (0 patients) and type III leaks (1 patient) P = 0.260. Conclusion Low mortality rates with anastomotic leak can be achieved. In centres with experienced radiological and endoscopic skills, most anastomotic leaks can be managed non-surgically. Disclosure All authors have declared no conflicts of interest.

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