Abstract
Background
Acute respiratory distress syndrome (ARDS) often requires controlled ventilation, yielding high mechanical power and possibly further injury. Veno-venous extracorporeal membrane ...oxygenation (VV-ECMO) can be used as a bridge to recovery, however, if this fails the end result is destroyed lung parenchyma. This condition is fatal and the only remaining alternative is lung transplantation. In the case study presented in this paper, lung transplantation was not an option given the critically ill state and the presence of HLA antibodies. Airway pressure release ventilation (APRV) may be valuable in ARDS, but APRV settings recommended in various patient and clinical studies are inconsistent. The Time Controlled Adaptive Ventilation (TCAV™) method is the most studied technique to set and adjust the APRV mode and uses an extended continuous positive airway pressure (CPAP) Phase in combination with a very brief Release Phase. In addition, the TCAV™ method settings are personalized and adaptive based on changes in lung pathophysiology. We used the TCAV™ method in a case of severe ARDS, which enabled us to open, stabilize and slowly heal the severely damaged lung parenchyma.
Case presentation
A 43-year-old woman presented with
Staphylococcus Aureus
necrotizing pneumonia. Progressive respiratory failure necessitated invasive mechanical ventilation and VV-ECMO. Mechanical ventilation (MV) was ultimately discontinued because lung protective settings resulted in trivial tidal volumes. She was referred to our academic transplant center for bilateral lung transplantation after the remaining infection had been cleared. We initiated the TCAV™ method in order to stabilize the lung parenchyma and to promote tissue recovery. This strategy was challenged by the presence of a large bronchopleural fistula, however, APRV enabled weaning from VV-ECMO and mechanical ventilation. After two months, following nearly complete surgical closure of the remaining bronchopleural fistulas, the patient was readmitted to ICU where she had early postoperative complications. Since other ventilation modes resulted in significant atelectasis and hypercapnia, APRV was restarted. The patient was then again weaned from MV.
Conclusions
The TCAV™ method can be useful to wean challenging patients with severe ARDS and might contribute to lung recovery. In this particular case, a lung transplantation was circumvented.
Crystal order is not restricted to the periodic atomic array, but can also be found in electronic systems such as the Wigner crystal or in the form of orbital order, stripe order and magnetic order. ...In the case of magnetic order, spins align parallel to each other in ferromagnets and antiparallel in antiferromagnets. In other, less conventional, cases, spins can sometimes form highly nontrivial structures called spin textures. Among them is the unusual, topologically stable skyrmion spin texture, in which the spins point in all the directions wrapping a sphere. The skyrmion configuration in a magnetic solid is anticipated to produce unconventional spin–electronic phenomena such as the topological Hall effect. The crystallization of skyrmions as driven by thermal fluctuations has recently been confirmed in a narrow region of the temperature/magnetic field (T–B) phase diagram in neutron scattering studies of the three-dimensional helical magnets MnSi (ref. 17) and Fe1−xCoxSi (ref. 22). Here we report real-space imaging of a two-dimensional skyrmion lattice in a thin film of Fe0.5Co0.5Si using Lorentz transmission electron microscopy. With a magnetic field of 50–70 mT applied normal to the film, we observe skyrmions in the form of a hexagonal arrangement of swirling spin textures, with a lattice spacing of 90 nm. The related T–B phase diagram is found to be in good agreement with Monte Carlo simulations. In this two-dimensional case, the skyrmion crystal seems very stable and appears over a wide range of the phase diagram, including near zero temperature. Such a controlled nanometre-scale spin topology in a thin film may be useful in observing unconventional magneto-transport effects.
Comorbidity: a network perspective Cramer, Angélique O J; Waldorp, Lourens J; van der Maas, Han L J ...
The Behavioral and brain sciences
33, Številka:
2-3
Journal Article
Recenzirano
The pivotal problem of comorbidity research lies in the psychometric foundation it rests on, that is, latent variable theory, in which a mental disorder is viewed as a latent variable that causes a ...constellation of symptoms. From this perspective, comorbidity is a (bi)directional relationship between multiple latent variables. We argue that such a latent variable perspective encounters serious problems in the study of comorbidity, and offer a radically different conceptualization in terms of a network approach, where comorbidity is hypothesized to arise from direct relations between symptoms of multiple disorders. We propose a method to visualize comorbidity networks and, based on an empirical network for major depression and generalized anxiety, we argue that this approach generates realistic hypotheses about pathways to comorbidity, overlapping symptoms, and diagnostic boundaries, that are not naturally accommodated by latent variable models: Some pathways to comorbidity through the symptom space are more likely than others; those pathways generally have the same direction (i.e., from symptoms of one disorder to symptoms of the other); overlapping symptoms play an important role in comorbidity; and boundaries between diagnostic categories are necessarily fuzzy.
Noonan syndrome (NS) is characterized by short stature, facial dysmorphisms and congenital heart defects. PTPN11 mutations are the most common cause of NS. Patients with NS have a predisposition for ...leukemia and certain solid tumors. Data on the incidence of malignancies in NS are lacking. Our objective was to estimate the cancer risk and spectrum in patients with NS carrying a PTPN11 mutation. In addition, we have investigated whether specific PTPN11 mutations result in an increased malignancy risk. We have performed a cohort study among 297 Dutch NS patients with a PTPN11 mutation (mean age 18 years). The cancer histories were collected from the referral forms for DNA diagnostics, and by consulting the Dutch national registry of pathology and the Netherlands Cancer Registry. The reported frequencies of cancer among NS patients were compared with the expected frequencies using population-based incidence rates. In total, 12 patients with NS developed a malignancy, providing a cumulative risk for developing cancer of 23% (95% confidence interval (CI), 8-38%) up to age 55 years, which represents a 3.5-fold (95% CI, 2.0-5.9) increased risk compared with that in the general population. Hematological malignancies occurred most frequently. Two malignancies, not previously observed in NS, were found: a malignant mastocytosis and malignant epithelioid angiosarcoma. No correlation was found between specific PTPN11 mutations and cancer occurrence. In conclusion, this study provides first evidence of an increased risk of cancer in patients with NS and a PTPN11 mutation, compared with that in the general population. Our data do not warrant specific cancer surveillance.
The tumour-stroma ratio (TSR) and tumour budding (TB) are two high-risk factors with potential to be implemented in the next TNM classification. The aim of the current study was to evaluate the ...practical application of the two biomarkers based on reproducibility, independency and prognostic value. Patients diagnosed with stage II or III colon cancer who underwent surgery between 2005 and 2016 were included. Both TSR and TB were scored on haematoxylin and eosin-stained tissue sections. The TSR, based on the relative amount of stroma, was scored in increments of 10%. TB was scored following the consensus guidelines; a bud was defined as ≤ 4 tumour cells. For analysis, three categories were used. Cohen’s kappa was used for reproducibility. The prognostic value was determined with survival analysis. In total, 246 patients were included. The TSR distribution was
N
= 137 (56%) stroma-low and
N
= 109 (44%) stroma-high. The TB distribution was TB-low
N
= 194 (79%), TB-intermediate
N
= 35 (14%) and TB-high
N
= 17 (7%). The reproducibility of the TSR was good (interobserver agreement kappa = 0.83 and intraobserver agreement kappa = 0.82), whereas the inter- and intraobserver agreement for scoring TB was moderate (kappa 0.47 and 0.45, respectively). The survival analysis showed an independent prognostic value for disease-free survival for TSR (HR 1.57; 95% CI 1.01–2.44;
p
= 0.048) and for TB-high (HR 2.01; 95% CI 1.02–3.96;
p
= 0.043). Based on current results, we suggest the TSR is a more reliable parameter in daily practice due to better reproducibility and independent prognostic value for disease-free survival.
Fast radio bursts (FRBs) are millisecond-duration radio transients
of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star ...magnetospheres
or relativistic shocks far from the central energy source
. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters
or variable polarization angles in some other apparently one-off events
. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks.
Background
The current standard to locate lymphatic vessels for lymphovenous anastomosis (LVA) is the use of indocyanine green (ICG)‐lymphangiography. Due to fluid retention and fibrosis of tissue in ...patients with lymphedema, often present in Caucasian patients, vessels deeper than 0.5 cm below the dermis cannot be visualized. We present our experiences with ultrasound in locating deeper lymphatic vessels in lower extremities.
Materials and Methods
In total, 28 patients with lymphedema and positive lymphoscintigraphy were included. With ultrasound, we located 82 lymphatic vessels in lower extremities preoperatively without the use of ICG marking. Vessel diameter, depth, and exact location were examined. Using a coordinate system, a mapping of the detected lymphatic vessels was created. The ultrasound findings were confirmed under microscope and ICG intraoperatively.
Results
In all, we detected 28 Caucasian patients and 82 lymphatic vessels with ultrasound preoperatively. On average, we found three lymphatic vessels (range, 2‐6) at each patient. Of the ultrasound‐detected lymphatic vessels, 90.2% could be verified intraoperatively under a microscope. Before skin incision, lymphatic vessels could be visualized in 40% of our patients with ICG. In the mapping of the lymphatic vessels, we found no significant pattern.
Conclusion
Ultrasound can precisely detect lymphatic vessels for efficient LVA operation without the prior use of ICG‐lymphangiography.
In this paper, we characterize major depression (MD) as a complex dynamic system in which symptoms (e.g., insomnia and fatigue) are directly connected to one another in a network structure. We ...hypothesize that individuals can be characterized by their own network with unique architecture and resulting dynamics. With respect to architecture, we show that individuals vulnerable to developing MD are those with strong connections between symptoms: e.g., only one night of poor sleep suffices to make a particular person feel tired. Such vulnerable networks, when pushed by forces external to the system such as stress, are more likely to end up in a depressed state; whereas networks with weaker connections tend to remain in or return to a non-depressed state. We show this with a simulation in which we model the probability of a symptom becoming 'active' as a logistic function of the activity of its neighboring symptoms. Additionally, we show that this model potentially explains some well-known empirical phenomena such as spontaneous recovery as well as accommodates existing theories about the various subtypes of MD. To our knowledge, we offer the first intra-individual, symptom-based, process model with the potential to explain the pathogenesis and maintenance of major depression.
Even though VR(Virtual Reality) shopping provides new opportunities for today’s marketers, it is not readily embraced by consumers. In this research, we aim to understand the underlying factors that ...facilitate the adoption of VR technology, by incorporating the consumer flow theory and the Technology Acceptance Model (TAM). Specifically, we find that factors that enhance consumer flow (i.e., telepresence, challenge, body ownership, and control) are positively associated with antecedent factors of technology acceptance (i.e. playfulness and usefulness), which are, in turn, associated with greater intentions to adopt and utilize VR technology in a consumer setting. We also investigate the moderating role of technology readiness and time distortion on the relationship between telepresence and playfulness. Data was collected by having participants use VR glasses in an actual VR supermarket that was created for this study. By elucidating factors that help consumer adoption of VR technology and emphasizing unique factors inherent to VR (i.e. telepresence and time distortion), this paper provides important contributions to the literature and implications for marketing managers.
The exact blood vessel trees segmented from fundus images provide important information required for screening and following-up of diabetic retinopathy and age-related macular degeneration. The ...trained deep neural network presents an automated prediction of the blood vessels in retinal fundus camera images in the publicly DRIVE database with accuracy up to 0.9533 and area under the receiver operating characteristic curve up to 0.9752, which is better than manual recognition by expert human eyes. A resizing technique is introduced and applied to the multi-level network combining dropout and spatial-dropout layers to obtain more generalised training. The proposed model has the potential for the classification of other types of images.
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