Endoscopic Balloon Therapy Klingler, Michael J; Kroh, Matthew
The Surgical clinics of North America
101, Issue:
2
Journal Article
Peer reviewed
Intragastric balloon therapy is an endoluminal treatment of obesity that is indicated for patients with moderate obesity (body mass index, 30-35 kg/m
) who have failed to lose weight with lifestyle ...and medical management. Treatment duration ranges from 4 to 12 months, and percent total body weight loss ranges from 6% to 15% at the time of balloon removal. Adverse events, such as bowel obstruction or gastric perforation, are rare, and early balloon removal because of intolerance is the most common complication. Long-term data are lacking, although weight regain after balloon removal seems to be common.
The rapid uptake of renewable energy technologies in recent decades has increased the demand of energy researchers, policymakers and energy planners for reliable data on the spatial distribution of ...their costs and potentials. For onshore wind energy this has resulted in an active research field devoted to analysing these resources for regions, countries or globally. A particular thread of this research attempts to go beyond purely technical or spatial restrictions and determine the realistic, feasible or actual potential for wind energy. Motivated by these developments, this paper reviews methods and assumptions for analysing geographical, technical, economic and, finally, feasible onshore wind potentials. We address each of these potentials in turn, including aspects related to land eligibility criteria, energy meteorology, and technical developments of wind turbine characteristics such as power density, specific rotor power and spacing aspects. Economic aspects of potential assessments are central to future deployment and are discussed on a turbine and system level covering levelized costs depending on locations, and the system integration costs which are often overlooked in such analyses. Non-technical approaches include scenicness assessments of the landscape, constraints due to regulation or public opposition, expert and stakeholder workshops, willingness to pay/accept elicitations and socioeconomic cost-benefit studies. For each of these different potential estimations, the state of the art is critically discussed, with an attempt to derive best practice recommendations and highlight avenues for future research.
•Review of over 300 studies on large-scale onshore wind potential assessments.•Analysis of geographic, technical, economic and ‘feasible’ potentials.•Identify weaknesses in methods and best practice examples.•Methods could improve transparency, validation, and sensitivities.•Further interdisciplinary research required on ‘feasible’ potentials.
Biofuels are currently the only available bulk renewable fuel. They have, however, limited expansion potential due to high land requirements and associated risks for biodiversity, food security, and ...land conflicts. We therefore propose to increase output from ethanol refineries in a land-neutral methanol pathway: surplus CO
-streams from fermentation are combined with H
from renewably powered electrolysis to synthesize methanol. We illustrate this pathway with the Brazilian sugarcane ethanol industry using a spatio-temporal model. The fuel output of existing ethanol generation facilities can be increased by 43%-49% or ~100 TWh without using additional land. This amount is sufficient to cover projected growth in Brazilian biofuel demand in 2030. We identify a trade-off between renewable energy generation technologies: wind power requires the least amount of land whereas a mix of wind and solar costs the least. In the cheapest scenario, green methanol is competitive to fossil methanol at an average carbon price of 95€ tCO
.
While wind power is a low-carbon renewable energy technology with relatively little land footprint, the necessary infrastructure expansion still has land-related environmental impacts. Brazil has ...seen more than a ten-fold increase in wind power capacity in the last decade. However, little is known about these impacts of wind power generation in Brazil compared to other world regions, although Brazilian wind power infrastructure is concentrated in the least protected ecosystems that are prone to degradation, desertification and species extinction. This study focuses on land-use impacts of past wind power generation development in four Brazilian federal states, covering 80% of the country's installed capacity. We assessed their spatial installation patterns, associated land-use and land cover change in the period before installation until 2018, and potential alternative installation locations, using a detailed wind turbine location database in combination with a high-resolution land-use and land cover map. In contrast to wind parks built in Europe, we found that 62% of the studied wind park area was covered by native vegetation and coastal sands. Overall, 3.2% of the total wind cluster area was converted from native vegetation to anthropogenic use. Wind parks installed mainly on native vegetation, on average, underwent higher land-use change compared to other wind parks. As Brazil intends to more than double its current wind power capacities by 2029, we explored possibilities to reduce environmental risks due to wind power expansion. We showed that this is feasible by integrating wind parks into human-altered areas, as sufficient wind resources there are available.
Background
In peroral endoscopic myotomy for Zenker’s diverticulum (Z-POEM), the cricopharyngeus muscle is divided within a submucosal tunnel started in the hypopharynx. We aimed to evaluate the ...safety and preliminary outcomes in patients who underwent a modified version of the Z-POEM where the tunnel is made directly overlying the cricopharyngeus, the
m
ucosal
i
ncision and
m
uscular
i
nterruption (MIMI) approach, and to compare these with patients who underwent a non-tunneled flexible endoscopic approach.
Methods
All patients with ZD who were treated by flexible endoscopy at our institution between January 2015 and February 2020 were identified by a retrospective chart review. Dysphagia symptoms were assessed using a validated scoring system.
Results
Nineteen patients with ZD underwent MIMI (mean age 76.1 years, 68.1% male) and seven patients underwent non-tunneled flexible endoscopic approach (mean age 64.4 years, 85.7% male) during the study period. Mean ZD size was 2.8 cm in the MIMI group and 1.9 cm in the non-tunneled group (
p
= 0.03). Clinical success was achieved in 17/19(89.5%) MIMI patients and 7/7(100%) of non-tunneled flexible endoscopic patients (
p
= 0.101). Dysphagia scores improved in both groups, although this difference was only significant in the MIMI group (
p
≤ 0.001). Recurrence occurred in 2/17(11.7%) MIMI patients and 3/7(42.9%) non-tunneled flexible endoscopic patients (
p
= 0.096). There were 4 complications, including one pharyngeal perforation requiring open surgical repair in a patient with a small ZD with an associated cricopharyngeal bar in the MIMI group. Median length of follow-up was 290 142; 465 days in the MIMI group and 1056 258; 1206 days in the non-tunneled group (
p
= 0.094).
Conclusions
MIMI is a technically feasible and effective treatment for ZD. Care should be taken in patients with a cricopharyngeal bar and small ZD, as this may increase the risk of perforation. Larger studies with long-term follow-up are needed to determine if MIMI reduces the risk of symptom recurrence when compared to non-tunneled flexible endoscopic approaches.
•Partial nephrectomy (PN) better preserves renal function than radical nephrectomy.•Renal function after PN is closely linked to parenchymal volume preservation (VP).•Surgeon assessment of VP, like ...3D calculation of VP, correlates with function.•Preoperative assessment of VP provides similar predictive ability prior to PN.•Estimation of postoperative glomerular filtration rate can impact patient-decision making and counseling.
Partial nephrectomy (PN) is standard for small renal masses, improving renal function by preserving renal parenchyma compared with radical nephrectomy. Recent work demonstrated that postoperative surgeon assessment of volume preservation (SAVP) and 3D imaging measurements agree and correlate with postoperative function. We hypothesize preoperative assessment of volume preservation (PAVP) with PN based on preoperative imaging will reliably indicate postoperative renal function.
Data were collected from 336 patients undergoing PN for suspected renal cancer by 40 surgeons at 12 centers in Europe and the United States within the Surface-Intermediate-Base International Consortium. Surgeons recorded PAVP and SAVP for individual patients; pre- and postoperative glomerular filtration rate (GFR) was estimated by Chronic Kidney Disease Epidemiology Collaboration equations. Correlations between PAVP, SAVP, and postoperative GFR were assessed with linear regression models. Bland–Altman analysis was used to assess agreement between PAVP and SAVP with a significant cutoff of 5%.
Median PAVP was 90% (interquartile range IQR 85%–100%) and SAVP was 90% (IQR: 80%–94%). PAVP and SAVP were moderately correlated (R2 = 0.67, P < 0.0001) and deemed “interchangeable” by Bland–Altman analysis at a 5% acceptable rate of difference (95% CI: −5.4, −3.1). Median postoperative GFR was 77.3 (IQR: 56.2, 92.0). Both PAVP (R2 = 0.82, P < 0.0001) and SAVP (R2 = 0.83, P < 0.0001) were correlated with postoperative GFR. Multivariable models utilizing volume-adjusted GFR based on PAVP or SAVP significantly and similarly predicted postoperative GFR (R2 = 0.72 for each).
Renal function is closely linked to the amount of parenchymal volume preservation, whether estimated prior to surgery (PAVP) or afterward (SAVP). PAVP provides reasonably accurate information for decision-making in patients considering PN.
Highlights ► We examine if multiple respiratory oscillators are present in brainstem rhombomeres. ► Respiratory oscillators are contained in several rhombomeres during development. ► Multiple ...oscillators are sufficient but not necessary for rhythm generation.
Abstract Purpose Dalfampridine extended-release (ER) tablets 10 mg BID have been approved for use in improving walking in people with multiple sclerosis (MS). This subgroup analysis evaluated the ...effects of dalfampridine ER 5 and 10 mg BID on distance walked, as assessed using the 6-minute walk (6MW) test. Methods This analysis of data from a randomized, placebo-controlled, double-blind study (N = 430) included only the 153 patients with 6MW data available. Participants (aged 18–70 years) were randomly assigned in a 1:1:1 ratio to receive dalfampridine ER 5 or 10 mg or placebo, BID for 4 weeks. The 6MW was used for assessing walking distance at baseline and 2 weeks after the start of treatment at the 26 study sites that were able to perform this test. Participants were administered the 12-item MS Walking Scale (MSWS-12), a patient-reported measure of the impact of MS on walking. Post hoc outcomes included the percentages of patients who achieved an increase from baseline in 6MW distance of ≥20% and who achieved a minimal clinically important difference (MCID) from baseline in 6MW distance, defined as ≥+55 m. Changes from baseline in walking speed (MSWS-12) were compared, stratified by subgroup that achieved ≥20% versus <20% improvement on the 6MW. The correlation between change in walking speed over time and subgroup (by change in distance walked) was evaluated. The tolerability of dalfampridine was assessed based on the prevalence of treatment-emergent adverse events (TEAEs). Findings In the post hoc analysis, the percentage of patients with an improvement in 6MW distance that met or exceeded the MCID was significantly greater with dalfampridine ER 10 mg BID relative to placebo (37.3% vs 12.2%; nominal P = 0.004). Similarly, the percentage with an improvement in 6MW distance of ≥20% was significantly greater with dalfampridine 10 mg BID relative to placebo (45.1% vs 14.3%; nominal P < 0.001). Regardless of treatment allocation, improvement in MSWS-12 was significantly greater in the subgroup that achieved a ≥20% improvement on the 6MW compared with the subgroup with <20% improvement (mean changes, –15.5 vs –7.2; nominal P = 0.041). The prevalences and types of TEAEs were consistent with those reported in previous studies. Implications Based on the MCID for 6MW, the use of dalfampridine ER 10 mg BID but not 5 mg BID was associated with statistically significant and clinically meaningful improvements in walking relative to placebo. The correlation between improvement on MSWS-12 and the 20% increase in 6MW distance suggests that an improvement on MSWS-12 is clinically relevant. These results, although highlighting a lack of efficacy of dalfampridine ER 5 mg BID, suggest that the 10-mg BID dose is effective for improving walking speed, as observed on short timed-walk tests, and for increasing distance walked over longer timed-walk periods. ClinicalTrials.gov identifier: NCT01328379.
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