Effects of long-term exposure to elevated CO2
 conditions in slow-growing plants using a 12
C-enriched CO2
-labelling technique

Abstract Background Hidradenoma papilliferum is a rare benign neoplasm arising from apocrine glands. It occurs commonly on the anogenital region of middle-aged women. It usually presents as a slow growing, solitary asymptomatic, skin colored or red nodule less than 1 cm in diameter. Case presentation The case is a 38-year-old, white woman who presented with a painful nodule occurring within a month in the himenal region of the posterior vaginal introitus. The nodule was excisied and the histology revealed a hidradenoma papilliferum. The diagnosis and treatment of hidradenoma papilliferum is possible with surgical removal and histopathological evaluation of nodules. Conclusion When an adult woman presents with a noduler lesion in the anogenital area, sexually transmitted diseases and other benign and malignant vulvar lesions, as well as malignant transformation is very rare but,should be kept in mind; however because it has been reported and long-term clinical follow-up is suggested

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Vegetation and microbes interact to preserve carbon in many wooded peatlands

Communications Earth & Environment ◽

10.1038/s43247-021-00136-4 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Hongjun Wang ◽

Jianqing Tian ◽

Huai Chen ◽

Mengchi Ho ◽

Rytas Vilgalys ◽

...

Keyword(s):

Microbial Composition ◽

Ecological Traits ◽

Low Latitude ◽

Carbon Decomposition ◽

Positive Effects ◽

Recalcitrant Carbon ◽

Effects Of Temperature ◽

Abiotic Controls ◽

Slow Growing

AbstractPeatlands have persisted as massive carbon sinks over millennia, even during past periods of climate change. The commonly accepted theory of abiotic controls (mainly anoxia and low temperature) over carbon decomposition cannot fully explain how vast low-latitude shrub/tree dominated (wooded) peatlands consistently accrete peat under warm and seasonally unsaturated conditions. Here we show, by comparing the composition and ecological traits of microbes between Sphagnum- and shrub-dominated peatlands, that slow-growing microbes decisively dominate the studied shrub-dominated peatlands, concomitant with plant-induced increases in highly recalcitrant carbon and phenolics. The slow-growing microbes metabolize organic matter thirty times slower than the fast-growing microbes that dominate our Sphagnum-dominated site. We suggest that the high-phenolic shrub/tree induced shifts in microbial composition may compensate for positive effects of temperature and/or drought on metabolism over time in peatlands. This biotic self-sustaining process that modulates abiotic controls on carbon cycling may improve projections of long-term, climate-carbon feedbacks in peatlands.

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Myopericytoma in the Antitragus of the Auricle: A Rare Tumor

Ear Nose & Throat Journal ◽

10.1177/0145561320984576 ◽

2020 ◽

pp. 014556132098457

Author(s):

Tae Seong Eo ◽

Jeong Hae Kie ◽

Hyun Seung Choi ◽

Junhui Jeong

Keyword(s):

Large Firm ◽

Rare Tumor ◽

Long Term Follow Up ◽

Slow Growing ◽

Rule Out

A myopericytoma in the auricle is rare. If an auricle contains a large, firm, red-brown mass, excision should be considered because the mass may be a myopericytoma. After excision, histopathological and immunohistochemical diagnoses are essential to rule out malignancy. Long-term follow-up is required because the tumor is slow-growing.

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Giant Parotid Pleomorphic Adenoma with Atypical Histological Presentation and Long-Term Recurrence-Free Follow-Up after Surgery: A Case Report and Review of the Literature

Case Reports in Dentistry ◽

10.1155/2020/8828775 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18

Author(s):

Mohammed AlKindi ◽

Sundar Ramalingam ◽

Lujain Abdulmajeed Hakeem ◽

Manal A. AlSheddi

Keyword(s):

Pleomorphic Adenoma ◽

Surgical Management ◽

Early Stage ◽

English Literature ◽

Benign Tumors ◽

Adjuvant Radiation ◽

Extracapsular Dissection ◽

Slow Growing

Salivary gland tumors (SGT) comprise 3% of all head and neck tumors, are mostly benign, and arise frequently in the parotid gland. Pleomorphic adenoma (PA) is the commonest SGT, representing 60-70% of all benign parotid tumors. Clinically, parotid PA presents as irregular, lobulated, asymptomatic, slow-growing preauricular mass, involving both superficial and deep lobes, and could grow to gigantic proportions. Histologically, PA has epithelial and mesenchymal elements in chondromyxoid matrix and is managed surgically. Based on a review of 43 cases reported in English literature since 1995, giant parotid PA is reported as large as 35 cm (diameter) and 7.3 kg (resected weight). Although rare, 10 cases of malignant transformation were reported in the review. Surgical management included extracapsular dissection (ECD), superficial parotidectomy, and total parotidectomy for benign tumors, and adjuvant radiation or chemotherapy for malignant tumors. We further present the case of a 36-year-old healthy male with slow-growing and asymptomatic giant parotid PA, of 4-year duration. The patient presented with firm, lobulated preauricular swelling, provisionally diagnosed as PA based on radiographic and cytological findings. The tumor was resected through ECD, and the patient had uneventful postoperative recovery and a 7-year recurrence-free follow-up period. Histological examination revealed epimyoepithelial proliferation punctuated by chondromyxoid areas, with extensive squamous metaplasia and keratin cysts. To the best of knowledge from indexed literature, giant parotid PA is rarely reported in Saudi Arabia. In addition to its rarity, this case is reported for its benign nature despite atypical histological presentation, successful surgical management without complications, and long-term recurrence-free follow-up. Based on this report, clinicians must be aware of atypical histological presentations associated with PA and plan suitable surgical management and follow-up to avoid morbidity. Nevertheless, attempts must be made to diagnose and manage these lesions at an early stage and before they reach gigantic proportions.

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Transketolase is involved in the control of Sigma B during chronic infection by Staphylococcus aureus

10.1101/538900 ◽

2019 ◽

Author(s):

Xin Tan ◽

Elodie Ramond ◽

Anne Jamet ◽

Baptiste Decaux-Tramoni ◽

Marion Dupuis ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Wild Type Strain ◽

Pentose Phosphate ◽

Chronic Infections ◽

Master Regulators ◽

Sigma B ◽

Viable Bacteria ◽

Infected Cells ◽

Slow Growing

AbstractStaphylococcus aureus is a leading cause of both acute and chronic infections in humans. Its ability to persist within host cells is thought to play an important role in chronicity and treatment failures. The importance of the pentose phosphate pathway (PPP) during S. aureus chronic infection is currently largely unexplored. Here, we focused on one key PPP enzyme, transketolase. We showed that inactivation of the unique gene encoding transketolase activity in S. aureus USA300 (Δtkt) led to an impaired growth in broth. Using time-lapse video imaging, we correlated this phenotype with a defect in early intracellular proliferation compared to wild-type strain. As determined by metabolomic analysis, tkt inactivation also had an important impact on S. aureus metabolism. We then monitored long-term intracellular persistence over 10 days by counting of viable bacteria. Unexpectedly for such a slow-growing strain, the Δtkt mutant was almost completely eliminated by endothelial cells after ten days, as opposed to a prototypical slow-growing ΔhemDBL mutant for which we recovered 1,000 fold more viable bacteria. We found that in infected cells, the transcriptional activity of the two master regulators Sigma B and RpiRc was drastically reduced in the Δtkt mutant compared to wild-type strain. Concomitantly, RNAIII transcription was strongly increased. This transcriptional profile is likely to explain the inability of this slow-growing mutant to sustain long-term intracellular survival, suggesting that TKT -or a functional PPP-is required for intracellular bacteria to enable a transcriptional program geared towards persistence.ImportanceStaphylococcus aureus is a leading cause of severe bacterial infections. This bacterium is readily internalized by non-professional phagocytes and infected cells have been proposed to play an important role in chronic infections and treatment failures.Here, we show the importance of the unique transketolase TKT of S. aureus USA300 in bacterial adaptation during chronic intracellular infection. We show that TKT is mandatory for the metabolomic homeostasis of S. aureus during intracellular persistence. This work unravels the critical role of TKT in the transcriptional regulation of the master regulators Sigma B, RpiRc and RNAIII linking the pentose phosphate pathway to the control of chronic S. aureus infections.

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The Responses of Rubisco Protein to Long-Term Exposure to Elevated CO2 in Rice and Bean Leaves

Photosynthesis: Mechanisms and Effects ◽

10.1007/978-94-011-3953-3_790 ◽

1998 ◽

pp. 3391-3394 ◽

Cited By ~ 2

Author(s):

Hiromi Nakano ◽

Amane Makino ◽

Tadahiko Mae

Keyword(s):

Elevated Co2 ◽

Bean Leaves

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Canopy position affects photosynthesis and anatomy in mature Eucalyptus trees in elevated CO2

Tree Physiology ◽

10.1093/treephys/tpaa117 ◽

2020 ◽

Author(s):

K Y Crous ◽

C Campany ◽

R Lopez ◽

F J Cano ◽

D S Ellsworth

Keyword(s):

Elevated Co2 ◽

Anatomical Variation ◽

Leaf Age ◽

Net Photosynthesis ◽

Leaf Mass Per Area ◽

Mesophyll Conductance ◽

Mature Leaves ◽

Canopy Position ◽

Palisade Cells

Abstract Leaves are exposed to different light conditions according to their canopy position, resulting in structural and anatomical differences with consequences for carbon uptake. While these structure–function relationships have been thoroughly explored in dense forest canopies, such gradients may be diminished in open canopies, and they are often ignored in ecosystem models. We tested within-canopy differences in photosynthetic properties and structural traits in leaves in a mature Eucalyptus tereticornis canopy exposed to long-term elevated CO2 for up to three years. We explored these traits in relation to anatomical variation and diffusive processes for CO2 (i.e., stomatal conductance, gs and mesophyll conductance, gm) in both upper and lower portions of the canopy receiving ambient and elevated CO2. While shade resulted in 13% lower leaf mass per area ratio (MA) in lower versus upper canopy leaves, there was no relationship between leaf Nmass and canopy gap fraction. Both maximum carboxylation capacity (Vcmax) and maximum electron transport (Jmax) were ~ 18% lower in shaded leaves and were also reduced by ~ 22% with leaf aging. In mature leaves, we found no canopy differences for gm or gs, despite anatomical differences in MA, leaf thickness and mean mesophyll thickness between canopy positions. There was a positive relationship between net photosynthesis and gm or gs in mature leaves. Mesophyll conductance was negatively correlated with mean parenchyma length, suggesting that long palisade cells may contribute to a longer CO2 diffusional pathway and more resistance to CO2 transfer to chloroplasts. Few other relationships between gm and anatomical variables were found in mature leaves, which may be due to the open crown of Eucalyptus. Consideration of shade effects and leaf-age dependent responses to photosynthetic capacity and mesophyll conductance are critical to improve canopy photosynthesis models and will improve understanding of long-term responses to elevated CO2 in tree canopies.

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Simulating Long-Term Development of Greenhouse Gas Emissions, Plant Biomass, and Soil Moisture of a Temperate Grassland Ecosystem under Elevated Atmospheric CO2

Agronomy ◽

10.3390/agronomy10010050 ◽

2019 ◽

Vol 10 (1) ◽

pp. 50

Author(s):

Ralf Liebermann ◽

Lutz Breuer ◽

Tobias Houska ◽

David Kraus ◽

Gerald Moser ◽

...

Keyword(s):

Soil Moisture ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Elevated Co2 ◽

Biomass Production ◽

Atmospheric Co2 ◽

N2o Emissions ◽

Gas Emissions ◽

Co2 Concentrations

The rising atmospheric CO2 concentrations have effects on the worldwide ecosystems such as an increase in biomass production as well as changing soil processes and conditions. Since this affects the ecosystem’s net balance of greenhouse gas emissions, reliable projections about the CO2 impact are required. Deterministic models can capture the interrelated biological, hydrological, and biogeochemical processes under changing CO2 concentrations if long-term observations for model testing are provided. We used 13 years of data on above-ground biomass production, soil moisture, and emissions of CO2 and N2O from the Free Air Carbon dioxide Enrichment (FACE) grassland experiment in Giessen, Germany. Then, the LandscapeDNDC ecosystem model was calibrated with data measured under current CO2 concentrations and validated under elevated CO2. Depending on the hydrological conditions, different CO2 effects were observed and captured well for all ecosystem variables but N2O emissions. Confidence intervals of ensemble simulations covered up to 96% of measured biomass and CO2 emission values, while soil water content was well simulated in terms of annual cycle and location-specific CO2 effects. N2O emissions under elevated CO2 could not be reproduced, presumably due to a rarely considered mineralization process of organic nitrogen, which is not yet included in LandscapeDNDC.

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