A new calculation metihodology for determining the static energy density at 0 K of each layer forming the slab (i.e., how the static energy density varies within the slab) is proposed. This work is ...the continuation of a previous one in which the vibrational free energy density of a slab was estimated. Now, it becomes possible to determine the free energy density profile of a slab delimited by any (hkl) surface and temperature, by adding the static contribution to the vibrational one. Moreover, it is now possible to estimate the surface free energy of a crystal face without calculating the free energy of the bulk. Finally, this model can be extended to the calculation of the free energy of the interface between (i) two identical crystals in a twinning relationship and (ii) two different crystals in an epitaxial relationship. The model was applied to the (10.4) (twinned and untwinned), (10.0) and (01.2) slabs of calcite (CaCO sub(3)): their free energy density profiles were calculated, as well as their surface/interface free energies. To the best of my knowledge, this is the first time that it is evaluated how a planar defect like a surface/interface affects the thermodynamic behavior of the underlying layers forming the crystal.
In patients with pancreatitis, early persisting organ failure is believed to be the most important cause of mortality. This study investigates the relation between the timing (onset and duration) of ...organ failure and mortality and its association with infected pancreatic necrosis in patients with necrotising pancreatitis.
We performed a post hoc analysis of a prospective database of 639 patients with necrotising pancreatitis from 21 hospitals. We evaluated the onset, duration and type of organ failure (ie, respiratory, cardiovascular and renal failure) and its association with mortality and infected pancreatic necrosis.
In total, 240 of 639 (38%) patients with necrotising pancreatitis developed organ failure. Persistent organ failure (ie, any type or combination) started in the first week in 51% of patients with 42% mortality, in 13% during the second week with 46% mortality and in 36% after the second week with 29% mortality. Mortality in patients with persistent multiple organ failure lasting <1 week, 1-2 weeks, 2-3 weeks or longer than 3 weeks was 43%, 38%, 46% and 52%, respectively (p=0.68). Mortality was higher in patients with organ failure alone than in patients with organ failure and infected pancreatic necrosis (44% vs 29%, p=0.04). However, when excluding patients with very early mortality (within 10 days of admission), patients with organ failure with or without infected pancreatic necrosis had similar mortality rates (28% vs 34%, p=0.33).
In patients with necrotising pancreatitis, early persistent organ failure is not associated with increased mortality when compared with persistent organ failure which develops further on during the disease course. Furthermore, no association was found between the duration of organ failure and mortality.
Endoscopic ultrasound (EUS)-guided tissue acquisition is extensively used, but the optimal sampling device is still a matter of debate. We performed meta-analyses on studies comparing fine-needle ...aspiration (FNA) with fine-needle biopsy (FNB) needles, and studies comparing different FNB needles.
Online databases were searched for randomized controlled trials (RCTs) of at least 50 cases with a suspected solid pancreatic or nonpancreatic lesion that compared FNA with FNB needles. Outcome measures included diagnostic accuracy, adequacy, number of passes, presence of tissue cores, and adverse events. We also performed meta-regression analysis on the effect of FNB design on diagnostic accuracy. Quality was assessed using the QUADAS-2 tool.
18 RCTs comparing FNA with FNB needles were included. FNB provided a higher pooled diagnostic accuracy (87 % vs. 80 %;
= 0.02) and tissue core rate (80 % vs. 62 %;
= 0.002), and allowed diagnosis with fewer passes (
= 0.03), in both pancreatic and nonpancreatic lesions. A total of 93 studies were included comparing different FNB devices. Pooled diagnostic accuracy was higher for forward-facing bevel needles than for the reverse bevel needle. In this analysis, study quality was low and heterogeneity was high (
= 80 %).
FNB outperformed FNA when sampling pancreatic and nonpancreatic lesions. Forward-facing bevel FNB needles seemed to outperform the reverse bevel FNB needle, but the low quality of evidence prevents us from making strong recommendations on the optimal FNB design.
Self-expandable metal stents (SEMSs) are effective for improving dysphagia in patients with incurable esophageal cancer but are also associated with recurrent dysphagia and adverse events. In the ...past decades, new SEMSs have been introduced, but also patients' risk profiles have altered. It is unknown if these changes have affected SEMS outcomes.
This retrospective cohort study was conducted in a tertiary referral center in the Netherlands. Patients who underwent palliative esophageal SEMS placement for malignant dysphagia between 1994 and 2017 were included. The primary outcome was to assess shifts over time with respect to recurrent dysphagia and adverse events after SEMS placement.
997 patients who underwent SEMS placement were included. Recurrent dysphagia occurred in 309 patients (31 %) and remained stable, although with a trend towards an increase over time (hazard ratio HR 1.02 per 1-year increase;
= 0.05). Migration rate significantly increased over time (HR 1.04 per 1-year increase;
= 0.01). SEMS-related complications occurred in 461 patients (46.2 %), with 207 (20.7 %) major and 336 (33.7 %) minor complications. Prior chemoradiotherapy was significantly associated with major complications (HR 1.69;
< 0.001). Pain was the most common adverse event and showed a significant increase over time (
< 0.01). Factors associated with pain were prior chemoradiotherapy, absence of a fistula, axial and radial forces, and squamous cell carcinoma.
Despite the introduction of novel esophageal SEMS designs, recurrent dysphagia has not declined over the years. Stent-related complications have increased in recent years, which seems to be mainly associated with more frequent use of chemoradiotherapy prior to SEMS placement.
The symptoms most commonly reported by patients affected by coronavirus disease (COVID-19) include cough, fever, and shortness of breath. However, other major events usually observed in COVID-19 ...patients (e.g., high blood pressure, arterial and venous thromboembolism, kidney disease, neurologic disorders, and diabetes mellitus) indicate that the virus is targeting the endothelium, one of the largest organs in the human body. Herein, we report a systematic and comprehensive evaluation of both clinical and preclinical evidence supporting the hypothesis that the endothelium is a key target organ in COVID-19, providing a mechanistic rationale behind its systemic manifestations.
Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new terminology updated from non-alcoholic fatty liver disease (NAFLD). In this study, we aim to estimate the global prevalence of ...MAFLD specifically in overweight and obese adults from the general population by performing a systematic review and meta-analysis through mining the existing epidemiological data on fatty liver disease.
We searched Medline, Embase, Web of Science, Cochrane and google scholar database from inception to November, 2020. DerSimonian-Laird random-effects model with Logit transformation was performed for data analysis. Sensitivity analysis and meta-regression were used to explore predictors of MAFLD prevalence in pooled statistics with high heterogeneity.
We identified 116 relevant studies comprised of 2,667,052 participants in general population with an estimated global MAFLD prevalence as 50.7% (95% CI 46.9-54.4) among overweight/obese adults regardless of diagnostic techniques. Ultrasound was the most commonly used diagnostic technique generating prevalence rate of 51.3% (95% CI, 49.1-53.4). Male (59.0%; 95% CI, 52.0-65.6) had a significantly higher MAFLD prevalence than female (47.5%; 95% CI, 40.7-54.5). Interestingly, MAFLD prevalence rates are comparable based on classical NAFLD and non-NAFLD studies in general population. The pooled estimate prevalence of comorbidities such as type 2 diabetes and metabolic syndrome was 19.7% (95% CI, 12.8-29.0) and 57.5% (95% CI, 49.9-64.8), respectively.
MAFLD has an astonishingly high prevalence rate in overweight and obese adults. This calls for attention and dedicated action from primary care physicians, specialists, health policy makers and the general public alike.
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