Involvement of a single periplasmic hydrogenase for both hydrogen uptake and production in some Desulfovibrio species

Au cours de cette étude, nous avons montré que plusieurs bactéries sulfato-réductrices possédant un nombre différent de gènes codant pour des hydrogénases, oxydent le lactate en absence de sulfate lorsqu'elles sont en coculture avec #Methanospirillum hungatei. L'efficacité du transfert d'hydrogène avec la bactérie méthanogène n'est pas corrélée avec le nombre de gènes codant pour l'hydrogénase chez ces bactéries sulfato-réductrices. #Desulfovibrio vulgaris Groningen, qui possède uniquement le gène de l'hydrogénase à nickel-fer (hydrogénase [NiFe]), oxyde l'hydrogène en présence de sulfate et produit de l'hydrogène au cours de la fermentation du pyruvate. L'hydrogénase de #D. vulgaris Groningen a été purifiée et caractérisée. Son poids moléculaire est de 87 kDA et elle est constituée de deux sous-unités différentes (60 et 28 kDa). L'hydrogénase de cette bactérie contient 10,6 atomes de fer, 0,9 atome de nickel et 12 atomes de soufre par molécule et son spectre d'absorption est caractéristique d'une protéine à centre fer-soufre. Les activités catalytiques de consommation et production d'hydrogène sont de 332 et 230 unités/mg de protéine, respectivement. Les cellules de #D. vulgarie Groningen contiennent exclusivement l'hydrogénase [NiFe] quelles que soient les conditions de croissance, ainsi que l'ont montré des études biochimiques et immunologiques. L'immunocytolocalisation de cryosections ultrafines de cellules ayant poussé sur différents milieux indique que l'hydrogénase [NiFe] est localisée dans l'espace périplasmique, le marquage étant plus important sur les cellules cultivées sur H2 et sulfate ou pyruvate seul que sur celles cultivées sur lactate et sulfate. Les résultats nous permettent de conclure que #D. vulgaris Groningen contient une seule hydrogénase de type [NiFe] située dans l'espace périplasmique tel que cela a été décrit chez #D. gigas. (Résumé d'auteur

The effect of age and font size on reading text on handheld computers

Though there have been many studies of computer based text reading, only a few have considered the small screens of handheld computers. This paper presents an investigation into the effect of varying font size between 2 and 16 point on reading text on a handheld computer. By using both older and younger participants the possible effects of age were examined. Reading speed and accuracy were measured and subjective views of participants recorded. Objective results showed that there was little difference in reading performance above 6 point, but subjective comments from participants showed a preference for sizes in the middle range. We therefore suggest, for reading tasks, that designers of interfaces for mobile computers provide fonts in the range of 8-12 point to maximize readability for the widest range of users

Narrow-Band Imaging in Transoral Laser Surgery for Early Glottic Cancer:A Randomized Controlled Trial

Objective: Assessing whether the additional use of narrow-band imaging (NBI) in transoral laser surgery (TOLS) for early laryngeal cancer improves clinical outcomes. Study Design: Randomized controlled trial, performed between September 2015 and November 2022. Setting: A tertiary referral hospital in The Netherlands. Methods: TOLS was carried out in 113 patients. The procedure was performed with white light imaging (WLI, n = 56) alone, or combined with NBI (n = 57). Patients received frequent follow-up laryngoscopy. Resection margin status, recurrence rate, and recurrence-free survival at 12 months, 18 months, and after study termination (maximum 86 months) were analyzed. Results: Thirty-one cases in the WLI group had a positive resection margin, versus 16 in the NBI group (p =.002). After 12 months, the recurrence-free survival was 92%: 87% for WLI versus 96% for NBI, p =.07. The recurrence rate was 7/56 (13%) for WLI, versus 2/57 (4%) for NBI, p =.09. After 18 months, the recurrence-free survival was 84% for WLI versus 96% for NBI, p =.02. The recurrence rate was 9/56 (16%) for WLI, versus 2/57 (4%) for NBI, p =.02. After study termination, the recurrence-free survival was 71% for WLI versus 83% for the NBI group (p =.08). The recurrence rate was 16/56 for WLI, versus 10/57 for NBI (p =.16). Conclusion: The additional use of NBI during TOLS significantly decreased the number of positive resection margins. Although not statistically significant at all time points, patients treated with NBI-supported TOLS showed a lower recurrence rate and better recurrence-free survival. Further studies in larger patient groups are needed to confirm these results.</p

Narrow-Band Imaging in Transoral Laser Surgery for Early Glottic Cancer:A Randomized Controlled Trial

Objective: Assessing whether the additional use of narrow-band imaging (NBI) in transoral laser surgery (TOLS) for early laryngeal cancer improves clinical outcomes. Study Design: Randomized controlled trial, performed between September 2015 and November 2022. Setting: A tertiary referral hospital in The Netherlands. Methods: TOLS was carried out in 113 patients. The procedure was performed with white light imaging (WLI, n = 56) alone, or combined with NBI (n = 57). Patients received frequent follow-up laryngoscopy. Resection margin status, recurrence rate, and recurrence-free survival at 12 months, 18 months, and after study termination (maximum 86 months) were analyzed. Results: Thirty-one cases in the WLI group had a positive resection margin, versus 16 in the NBI group (p =.002). After 12 months, the recurrence-free survival was 92%: 87% for WLI versus 96% for NBI, p =.07. The recurrence rate was 7/56 (13%) for WLI, versus 2/57 (4%) for NBI, p =.09. After 18 months, the recurrence-free survival was 84% for WLI versus 96% for NBI, p =.02. The recurrence rate was 9/56 (16%) for WLI, versus 2/57 (4%) for NBI, p =.02. After study termination, the recurrence-free survival was 71% for WLI versus 83% for the NBI group (p =.08). The recurrence rate was 16/56 for WLI, versus 10/57 for NBI (p =.16). Conclusion: The additional use of NBI during TOLS significantly decreased the number of positive resection margins. Although not statistically significant at all time points, patients treated with NBI-supported TOLS showed a lower recurrence rate and better recurrence-free survival. Further studies in larger patient groups are needed to confirm these results.</p

Narrow-Band Imaging in Transoral Laser Surgery for Early Glottic Cancer:A Randomized Controlled Trial

Objective: Assessing whether the additional use of narrow-band imaging (NBI) in transoral laser surgery (TOLS) for early laryngeal cancer improves clinical outcomes. Study Design: Randomized controlled trial, performed between September 2015 and November 2022. Setting: A tertiary referral hospital in The Netherlands. Methods: TOLS was carried out in 113 patients. The procedure was performed with white light imaging (WLI, n = 56) alone, or combined with NBI (n = 57). Patients received frequent follow-up laryngoscopy. Resection margin status, recurrence rate, and recurrence-free survival at 12 months, 18 months, and after study termination (maximum 86 months) were analyzed. Results: Thirty-one cases in the WLI group had a positive resection margin, versus 16 in the NBI group (p =.002). After 12 months, the recurrence-free survival was 92%: 87% for WLI versus 96% for NBI, p =.07. The recurrence rate was 7/56 (13%) for WLI, versus 2/57 (4%) for NBI, p =.09. After 18 months, the recurrence-free survival was 84% for WLI versus 96% for NBI, p =.02. The recurrence rate was 9/56 (16%) for WLI, versus 2/57 (4%) for NBI, p =.02. After study termination, the recurrence-free survival was 71% for WLI versus 83% for the NBI group (p =.08). The recurrence rate was 16/56 for WLI, versus 10/57 for NBI (p =.16). Conclusion: The additional use of NBI during TOLS significantly decreased the number of positive resection margins. Although not statistically significant at all time points, patients treated with NBI-supported TOLS showed a lower recurrence rate and better recurrence-free survival. Further studies in larger patient groups are needed to confirm these results.</p

Narrow-Band Imaging in Transoral Laser Surgery for Early Glottic Cancer:A Randomized Controlled Trial

Objective: Assessing whether the additional use of narrow-band imaging (NBI) in transoral laser surgery (TOLS) for early laryngeal cancer improves clinical outcomes. Study Design: Randomized controlled trial, performed between September 2015 and November 2022. Setting: A tertiary referral hospital in The Netherlands. Methods: TOLS was carried out in 113 patients. The procedure was performed with white light imaging (WLI, n = 56) alone, or combined with NBI (n = 57). Patients received frequent follow-up laryngoscopy. Resection margin status, recurrence rate, and recurrence-free survival at 12 months, 18 months, and after study termination (maximum 86 months) were analyzed. Results: Thirty-one cases in the WLI group had a positive resection margin, versus 16 in the NBI group (p =.002). After 12 months, the recurrence-free survival was 92%: 87% for WLI versus 96% for NBI, p =.07. The recurrence rate was 7/56 (13%) for WLI, versus 2/57 (4%) for NBI, p =.09. After 18 months, the recurrence-free survival was 84% for WLI versus 96% for NBI, p =.02. The recurrence rate was 9/56 (16%) for WLI, versus 2/57 (4%) for NBI, p =.02. After study termination, the recurrence-free survival was 71% for WLI versus 83% for the NBI group (p =.08). The recurrence rate was 16/56 for WLI, versus 10/57 for NBI (p =.16). Conclusion: The additional use of NBI during TOLS significantly decreased the number of positive resection margins. Although not statistically significant at all time points, patients treated with NBI-supported TOLS showed a lower recurrence rate and better recurrence-free survival. Further studies in larger patient groups are needed to confirm these results.</p

Narrow-Band Imaging in Transoral Laser Surgery for Early Glottic Cancer:A Randomized Controlled Trial

Objective: Assessing whether the additional use of narrow-band imaging (NBI) in transoral laser surgery (TOLS) for early laryngeal cancer improves clinical outcomes. Study Design: Randomized controlled trial, performed between September 2015 and November 2022. Setting: A tertiary referral hospital in The Netherlands. Methods: TOLS was carried out in 113 patients. The procedure was performed with white light imaging (WLI, n = 56) alone, or combined with NBI (n = 57). Patients received frequent follow-up laryngoscopy. Resection margin status, recurrence rate, and recurrence-free survival at 12 months, 18 months, and after study termination (maximum 86 months) were analyzed. Results: Thirty-one cases in the WLI group had a positive resection margin, versus 16 in the NBI group (p =.002). After 12 months, the recurrence-free survival was 92%: 87% for WLI versus 96% for NBI, p =.07. The recurrence rate was 7/56 (13%) for WLI, versus 2/57 (4%) for NBI, p =.09. After 18 months, the recurrence-free survival was 84% for WLI versus 96% for NBI, p =.02. The recurrence rate was 9/56 (16%) for WLI, versus 2/57 (4%) for NBI, p =.02. After study termination, the recurrence-free survival was 71% for WLI versus 83% for the NBI group (p =.08). The recurrence rate was 16/56 for WLI, versus 10/57 for NBI (p =.16). Conclusion: The additional use of NBI during TOLS significantly decreased the number of positive resection margins. Although not statistically significant at all time points, patients treated with NBI-supported TOLS showed a lower recurrence rate and better recurrence-free survival. Further studies in larger patient groups are needed to confirm these results.</p

Geriatric assessment of patients treated for cutaneous head and neck malignancies in a tertiary referral center:Predictors of postoperative complications

Introduction: As cutaneous head and neck malignancies are highly prevalent especially in older patients, the risk of surgical complications is substantial in this potentially vulnerable population. The objective of this study was to evaluate the value of geriatric assessment of this population with respect to postoperative complications. Methods: Patients were prospectively included in OncoLifeS, a databiobank. Before surgery, patients underwent a geriatric assessment including multiple validated screening tools for frailty, comorbidity, polypharmacy, nutrition, functional status, social support, cognition and psychological status. Postoperatively, complications (Clavien-Dindo ≥ grade II) were registered. Uni- and multivariable logistic regression analyses were performed yielding odds ratios (ORs) and 95% confidence intervals (95%CIs). Results: 151 patients undergoing surgery for cutaneous head and neck malignancies were included in this study (mean age 78.9 years, 73.5% male). In a multivariable analysis, frailty measured by the Geriatric 8 (G8) (OR = 6.34; 95%CI:1.73–23.25) was the strongest independent predictor of postoperative complications, among other predictors such as major treatment intensity (OR = 2.73; 95%CI:1.19–6.26) and general anesthesia (OR = 4.74; 95%CI:1.02–22.17), adjusted for age and sex. Conclusion: Frailty, measured by G8, is the strongest predictor of postoperative complications in patients undergoing surgery for cutaneous head and neck malignancies in addition to treatment intensity and type of anesthesia. Geriatric screening on multiple domains is recommended for patients with cutaneous malignancies undergoing head and neck surgery is recommended, as this population includes old patients and frequently suffers postoperative complications

Matching Regge Theory to the OPE

The spectra of masses and decay constants for non-strange meson resonances in the energy range 0--2.5 GeV is analyzed. It is known from meson phenomenology that for given quantum numbers these spectra approximately follow linear trajectories with a universal slope. These facts can be understood in terms of an effective string description for QCD. For light meson states the trajectories deviate noticeably from the linear behavior. We investigate the possible corrections to the linear trajectories by matching two-point correlators of quark currents to the Operator Product Expansion (OPE). We find that the allowed modifications to the linear Regge behavior must decrease rapidly with the principal quantum number. After fitting the lightest states in each channel and certain low-energy constants the whole spectrum for meson masses and residues is obtained in a satisfactory agreement with phenomenology. We briefly speculate on possible implications for the QCD effective string.Comment: 24 pages, Latex, significant changes in discussion of fits, more refs adde

Comparison of narrow band and fluorescence molecular imaging to improve intraoperative tumour margin assessment in oral cancer surgery

Objective: New techniques have emerged to aid in preventing inadequate margins in oral squamous cell carcinoma (OSCC) surgery, but studies comparing different techniques are lacking. Here, we compared narrow band imaging (NBI) with fluorescence molecular imaging (FMI), to study which intraoperative technique best assesses the mucosal tumour margins.Materials and Methods: NBI was performed in vivo and borders were marked with three sutures. For FMI, patients received 75 mg of unlabelled cetuximab followed by 15 mg cetuximab-800CW intravenously-two days prior to surgery. The FMI borders were defined on the excised specimen. The NBI borders were correlated with the FMI outline and histopathology.Results: Sixteen patients were included, resulting in 31 NBI and 30 FMI measurements. The mucosal border was delineated within 1 mm of the tumour border in 4/31 (13 %) of NBI and in 16/30 (53 %) FMI cases (p = 0.0008), and within 5 mm in 23/31 (74 %) of NBI and in 29/30 (97 %) of FMI cases (p = 0.0048). The median distance between the tumour border and the imaging border was significantly greater for NBI (3.2 mm, range −6.1 to 12.8 mm) than for FMI (0.9 mm, range −3.0 to 7.4 mm; p = 0.028). Submucosal extension and previous irradiation reduced NBI accuracy.Conclusion: Ex vivo FMI performed more accurately than in vivo NBI in mucosal margin assessment, mainly because NBI cannot detect submucosal extension. NBI adequately identified the mucosal margin especially in early-stage and not previously irradiated tumours, and may therefore be preferable in these tumours for practical and cost-related reasons.</p