Sort by: Order: Results:

Now showing items 1-6 of 6
  • Song, Chaoqing; Luan, Junwei; Xu, Xiaofeng; Ma, Minna; Aurela, Mika; Lohila, Annalea; Mammarella, Ivan; Alekseychik, Pavel; Tuittila, Eeva-Stiina; Gong, Wei; Chen, Xiuzhi; Meng, Xianhong; Yuan, Wenping (2020)
    Wetlands are one of the most important terrestrial ecosystems for land-atmosphere CH4 exchange. A new process-based, biophysical model to quantify CH4 emissions from natural wetlands was developed and integrated into a terrestrial ecosystem model (Integrated Biosphere Simulator). The new model represents a multisubstance system (CH4, O-2, CO2, and H-2) and describes CH4 production, oxidation, and three transport processes (diffusion, plant-mediated transport, and ebullition). The new model uses several critical microbial mechanisms to represent the interaction of anaerobic fermenters and homoacetogens, hydrogenotrophic, and acetoclastic methanogens, and methanotrophs in CH4 production and oxidation. We applied the model to 24 different wetlands globally to compare the simulated CH4 emissions to observations and conducted a sensitivity analysis. The results indicated that (1) for most sites, the model was able to capture the magnitude and variation of observed CH4 emissions under varying environmental conditions; (2) the parameters that regulate dissolved organic carbon and acetate production, and acetoclastic methanogenesis had the significant impact on simulated CH4 emissions; (3) the representation of the process components of CH4 cycling showed that CH4 oxidation was about half or more of CH4 production, and plant-mediated transport was the dominant pathway at most sites; and (4) the seasonality of simulated CH4 emissions can be controlled by soil temperature, water table position, or combinations thereof.
  • UroSoMe Collaborators; Leow, Jeffrey J. J.; Tan, Wei Shen; Tan, Wei Phin; Tikkinen, Kari A. O.; Teoh, Jeremy Yuen-Chun (2022)
    PurposeThe COVID-19 pandemic has led to competing strains on hospital resources and healthcare personnel. Patients with newly diagnosed invasive urothelial carcinomas of bladder (UCB) upper tract (UTUC) may experience delays to definitive radical cystectomy (RC) or radical nephro-ureterectomy (RNU) respectively. We evaluate the impact of delaying definitive surgery on survival outcomes for invasive UCB and UTUC.MethodsWe searched for all studies investigating delayed urologic cancer surgery in Medline and Embase up to June 2020. A systematic review and meta-analysis was performed.ResultsWe identified a total of 30 studies with 32,591 patients. Across 13 studies (n = 12,201), a delay from diagnosis of bladder cancer/TURBT to RC was associated with poorer overall survival (HR 1.25, 95% CI: 1.09-1.45, p = 0.002). For patients who underwent neoadjuvant chemotherapy before RC, across the 5 studies (n = 4,316 patients), a delay between neoadjuvant chemotherapy and radical cystectomy was not found to be significantly associated with overall survival (pooled HR 1.37, 95% CI: 0.96-1.94, p = 0.08). For UTUC, 6 studies (n = 4,629) found that delay between diagnosis of UTUC to RNU was associated with poorer overall survival (pooled HR 1.55, 95% CI: 1.19-2.02, p = 0.001) and cancer-specific survival (pooled HR of 2.56, 95% CI: 1.50-4.37, p = 0.001). Limitations included between-study heterogeneity, particularly in the definitions of delay cut-off periods between diagnosis to surgery.ConclusionsA delay from diagnosis of UCB or UTUC to definitive RC or RNU was associated with poorer survival outcomes. This was not the case for patients who received neoadjuvant chemotherapy.
  • Schetelig, Johannes; Hoek, Jennifer; Stilgenbauer, Stephan; Middeke, Jan Moritz; Andersen, Niels Smedegaard; Fox, Christopher P.; Lenhoff, Stig; Volin, Liisa; Shimoni, Avichai; Schroyens, Wilfried; van Gelder, Michel; Bunjes, Donald; van Biezen, Anja; Baldauf, Henning; de Wreede, Liesbeth C.; Tournilhac, Olivier; Kroeger, Nicolaus; Yakoub-Agha, Ibrahim; Dreger, Peter (2021)
  • Kainulainen, S.; Tornwall, J.; Koivusalo, A. M.; Suominen, A. L.; Lassus, Patrik (2017)
    Objectives: Glucocorticoids are widely used in association with major surgery of the head and neck to improve postoperative rehabilitation, shorten intensive care unit and hospital stay, and reduce neck swelling. This study aimed to clarify whether peri-and postoperative use of dexamethasone in reconstructive head and neck cancer surgery is associated with any advantages or disadvantages. Materials and methods: This prospective double-blind randomized controlled trial comprised 93 patients. A total dose of 60 mg of dexamethasone was administered to 51 patients over three days peri-and post-operatively. The remaining 42 patients served as controls. The main primary outcome variables were neck swelling, length of intensive care unit and hospital stay, duration of intubation or tracheostomy, and delay to start of possible radiotherapy. Complications were also recorded. Results: No statistical differences emerged between the two groups in any of the main primary outcome variables. However, there were more major complications, especially infections, needing secondary surgery within three weeks of the operation in patients receiving dexamethasone than in control patients (27% vs. 7%, p = 0.012). Conclusions: The use of dexamethasone in oral cancer patients with microvascular reconstruction did not provide a benefit. More major complications, especially infections, occurred in patients receiving dexamethasone. Our data thus do not support the use of peri-and postoperative dexamethasone in oropharyngeal cancer patients undergoing microvascular reconstruction. (C) 2016 Elsevier Ltd. All rights reserved.
  • Rinne, Janne; Tuittila, Eeva-Stiina; Peltola, Olli; Li, Xuefei; Raivonen, Maarit; Alekseychik, Pavel; Haapanala, Sami; Pihlatie, Mari; Aurela, Mika; Mammarella, Ivan; Vesala, Timo (2018)
    We have analyzed decade-long methane flux data set from a boreal fen, Siikaneva, together with data on environmental parameters and carbon dioxide exchange. The methane flux showed seasonal cycle but no systematic diel cycle. The highest fluxes were observed in July-August with average value of 73 nmol m(-2) s(-1). Wintertime fluxes were small but positive, with January-March average of 6.7 nmol m(-2) s(-1). Daily average methane emission correlated best with peat temperatures at 20-35 cm depths. The second highest correlation was with gross primary production (GPP). The best correspondence between emission algorithm and measured fluxes was found for a variable-slope generalized linear model (r(2) = 0.89) with peat temperature at 35 cm depth and GPP as explanatory variables, slopes varying between years. The homogeneity of slope approach indicated that seasonal variation explained 79% of the sum of squares variation of daily average methane emission, the interannual variation in explanatory factors 7.0%, functional change 5.3%, and random variation 9.1%. Significant correlation between interannual variability of growing season methane emission and that of GPP indicates that on interannual time scales GPP controls methane emission variability, crucially for development of process-based methane emission models. Annual methane emission ranged from 6.0 to 14 gC m(-2) and was 2.7 +/- 0.4% of annual GPP. Over 10-year period methane emission was 18% of net ecosystem exchange as carbon. The weak relation of methane emission to water table position indicates that space-to-time analogy, used to extrapolate spatial chamber data in time, may not be applicable in seasonal time scales.
  • Nilsen, Ole Jacob; Holm, Henriette Veiby; Ekerhult, Teresa O.; Lindqvist, Klas; Grabowska, Beata; Persson, Beata; Sairanen, Jukka (2022)
    Background: Open surgical treatment of short bulbar urethral strictures (urethroplasty) is commonly performed as transecting excision and primary anastomosis (tEPA) or buccal mucosa grafting (BMG). Erectile dysfunction and penile complications have been reported, but there is an absence of randomised trials. Objective: To evaluate sexual dysfunction and penile complications after urethroplasty with tEPA versus BMG. Design, setting, and participants: Centres in Finland, Sweden and Norway participated. Patients with a bulbar urethral stricture of Intervention: Patients were randomised to either tEPA or BMG urethroplasty. Outcome measurements and statistical analysis: Sexual dysfunction was measured using the International Index of Erectile Function, 5-item version (IIEF-5) and a penile complications questionnaire (PCQ) designed for this study. Continuous data were analysed using analysis of covariance and categorical data were compared using a chi(2) test. Results and limitations: A total of 151 patients were randomised to either tEPA (n = 75) or BMG (n = 76). The tEPA group reported more penile complications (p = 0.02), especially reduced glans filling (p = 0.03) and a shortened penis (p = 0.001). There were no differences in postoperative IIEF-5 total scores. Recurrence rates were similar in both groups (12.9%) but the study was not designed to detect differences in recurrence rates. The PCQ is not validated, which is a limitation. Conclusions: More patients reported penile complications after urethroplasty with tEPA than with BMG. This should be considered when choosing the operative method, and patients should be informed accordingly. Patient summary: This study compared two common operations for repair of narrowing of the male urethra. Neither of the two methods seems to cause worsened erections. However, penile problems are more common after the transection technique than after the grafting technique. (C) 2021 The Author(s). Published by Elsevier B.V. on behalf of European Association of Urology.