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Vahid Darvishi

and 1 more

An in-vivo study of the distribution of magnetic nanoparticles in the tissue after injection and effects of infusion rate on the distribution by using a more precise and cost-effective method was the primary goal of the authors. To achieve this aim, twelve Balb/c mice were used to run an experimental investigation. A Hamilton syringe was used for injection of the magnetic fluid and a 26-gauge Hamilton needle was also used to reduce the backflow of the fluid after injection. After the injection of nanoparticles, tissues were fixed in formalin immediately. Then, they were cut and photographed from the cutting surface of each sample and then were stained by a specific chemical reaction called Perls’ reaction. Results showed that not only the cost of experiments reduced extremely by using the direct cutting method instead of using MRI but also a cavity made by fluid was observed in which in the MRI method was imperceptible. Results indicate that by increasing the infusion rate from 5 μl/min to 10 μl/min, the penetration depth increased and at the infusion rate of 10 μl/min was about 1.16 up to 2.2 times bigger than the infusion rate of 5 μl/min. It was also found that there was an increase in the number of microcracks in the tissue by increasing the infusion rate which had to be avoided to reduce exiting out of the magnetic fluid into the healthy tissue around the tumor. Results indicated that lower infusion rates are better for having better distribution but in some specific situations, higher infusion rates could be more useful. The last noteworthy point of examinations was the feasibility of Multi-point injection which is used in several numerical investigations and simulations before but in laboratory investigation cannot be used due to the leakage of nanoparticles.

Fatima Osman

and 2 more

The coronavirus disease 19 (COVID-19) pandemic has resulted in widespread economic, health and social disruptions. The delivery of cardiovascular care has been stifled during the pandemic in order to adhere to infection control measures as a way of protecting patients and the workforce at large. This cautious approach has been protective since individuals with COVID-19 and cardiovascular disease are anticipated to have poorer outcomes and an increased risk of death. The combination of postponing elective cardiovascular surgeries, reduced acute care and long-term cardiac damage directly resulting from COVID-19 will likely have increased the demand for cardiac care, particularly from patients presenting with more severe symptoms. The combination of increased demand and inhibited supply will likely result in huge backlog of unmet patients’ needs. The novelty, virulence and infectivity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused substantial morbidity and mortality which have necessitated modifications to the UK government’s healthcare strategy. Without improving cost efficiency, the UK’s ageing population will likely need an increasing spend on cardiac surgery simply to maintain the same level of service. However, the government’s short-term increase in spending is unsustainable especially in the face of ongoing economic uncertainty. This means that the long-term impact of COVID-19 will only increase the need to find innovative ways of delivering equivalent or superior cardiac care at a reduced unit cost.

Rebecca Ward

and 7 more

Introduction: Women with gestational diabetes (GDM) are at greatly increased risk of type 2 diabetes (T2DM). The UK guidance recommends screening for T2DM at around 6 weeks post-partum and annually thereafter. We evaluated conformity to this guidance in two separate time periods. Methods: The proportion of tests performed within guidance was assessed using longitudinal plasma glucose and glycated haemoglobin data in two cohorts (1999-2007, n=251; 2015-2016, n=260) from hospital records on women previously diagnosed with GDM. Results: In the 1999-2007 and 2015-2016 cohorts, 59.8% and 35.0% of women had the recommended post-partum testing, respectively (p<0.001); just 13.5% and 14.2%, respectively, underwent the first annual test on time. During long-term follow-up of the 1999-2007 cohort (median follow-up: 12.3 years), the proportion of women tested in any given year averaged 34.2% over a 17-year period; there was a progressive decline in the proportion of women receiving a yearly test with time since delivery (p=0.002). Over the follow-up period, 85 women from the 1999-2007 cohort developed blood test results in the diabetic range with a median time to presumed DM diagnosis of 5.2 years (range 0.11-15.95 years). Kaplan-Meier analysis showed that 18.8% of women had blood test results in the diabetes range by 5 years and 37.8% by 10 years post-partum. Conclusions: Despite high profile guidelines and a clear clinical rationale to screen women with a past diagnosis of GDM, many women did not receive adequate screening for T2DM, both in the short- and long-term. This suggests alternative approaches are needed to ensure effective follow-up of this high-risk group. To have an impact, interventions need to be tailored to a young, generally healthy group in which traditional approaches to follow-up may not be best suited.

Hiroki Nishikawa

and 5 more

Background and aims: The causal relationship between sarcopenia and sleep disorder in patients with chronic liver disease (CLDs) is unclear. We aimed examine the influence of sarcopenia-related factors (grip strength (GS) and muscle mass) on the progression of sleep disorder in patients with chronic liver disease (n=182, 46 cirrhotic cases, median age=64 years). Methods: Sleep quality was evaluated by the Japanese version of Pittsburgh Sleep Quality Index (PSQI-J). PSQI-J >6 points was defined as sleep disorder. In all analyzed patients, evaluation using PSQI-J questionnaire was performed twice or more during the follow-up period. Time interval from the date of baseline PSQI-J and the first confirmed date of elevation of PSQI-J score was calculated. Our primary endpoint was the elevation of PSQI-J score compared to the baseline PSQI-J score. GS decline was diagnosed with a GS of <26 kg for male and <18 kg for female. Loss of muscle mass was diagnosed by a skeletal muscle index of <7.0 kg/m2 for male and <5.7 kg/m2 for female on bioelectrical impedance analysis. Results: The median PSQI-J score was 5. PSQI-J >6 points at baseline was found in 83 patients (45.6%). In patients with GS decline (n=48), the 3-year cumulative elevation rate of PSQI-J score was 82.4%, while in patients with GS non-decline, that was 36.2% (P<0.0001). In patients with SMI decline (n=64), the 3-year cumulative elevation rate of PSQI-J score was 60.6%, while in patients with SMI non-decline, that was 43.4% (P=0.1822). On the multivariate analysis of factors associated with the elevation of PSQI-J score, only GS decline (P=0.0002) was a significant factor. Conclusions: Reduced GS rather than loss of muscle mass is independently associated with an elevated risk for the progression of sleep disorder in CLD patients.

Jerome Lechien

and 14 more

Objective: To investigate prevalence and epidemiological and clinical factors associated with OD and GD in COVID-19 patients according to the disease severity. Study design: Cross-sectional study. Methods: A total of 2,579 patients with a positive diagnosis of COVID-19 were identified between March 22 and June 3, 2020 from 18 European hospitals. Epidemiological and clinical data were extracted. Otolaryngological symptoms, including OD and GD were collected through patient-reported outcome questionnaire and sniffin-sticks tests were carried out in a subset of patients. Results: A total of 2,579 patients were included, including 2,166 mild (84.0%), 144 moderate (5.6%) and 269 severe-to-critical (10.4%) patients. Mild patients presented an otolaryngological picture of the disease with OD, GD, nasal obstruction, rhinorrhea and sore throat as the most prevalent symptoms. The prevalence of subjective OD, GD were 73.7 and 46.8% and decrease with the severity of the disease. Females had higher prevalence of subjective OD and GD compared with males. Diabetes was associated with a higher risk to develop GD. Among the subset of patients who benefited from psychophysical olfactory evaluations, there were 75 anosmic, 43 hyposmic and 113 normosmic patients. The prevalence of anosmia significantly decreased with the severity of the disease. Anosmia or hyposmia were not associated with any nasal disorder, according to SNOT-22. Conclusion: OD and GD are more prevalent in patients with mild COVID-19 compared with individuals with moderate, severe or critical diseases. Females might have a higher risk of developing OD and GD compared with males.
Objective. This study examined the predictive ability of established Maternal Early Warning systems (MEWS) for different types of maternal morbidity, in order to discern an optimal early warning system. Design. Retrospective cohort study. Setting. Four-hospital urban academic system. Population. All patients admitted to the obstetric services of this hospital system in 2018. Methods. All patient vital signs were collected and three sets of published MEWS criteria were evaluated in relation to maternal morbidity. The test characteristics of each MEWS, as well as for heart rate, blood pressure, and oxygen saturation individually and in different combinations were compared. Main Outcome Measures. Maternal morbidity, defined as a composite of hemorrhage, infection, acute cardiac disease, and acute respiratory disease, ascertained from informatics and administrative data. Results. Of 14,597 obstetric admissions, 2,451 patients experienced composite morbidity (16.8%). The sensitivities (15.3% - 64.8%), specificities (56.8% - 96.1%), and positive predictive values (22.3% - 44.5%) of the three MEWS criteria ranged. Of patients with any morbidity, 28% met criteria for the most liberal vital sign combination, while only 2% met criteria for the most restrictive parameters, compared to 14% and 1% of patients without morbidity, respectively. Sensitivity of all vital sign combinations was low (maximum 28.2%), while specificity ranged from 86.1 – 99.3%. Conclusions. Though all MEWS criteria demonstrated poor sensitivity for maternal morbidity, permutations of the most abnormal vital signs have high specificity, suggesting that MEWS may be better implemented as a trigger tool to target more sensitive screening techniques for maternal morbidity.

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Yue Liang

and 5 more

Internal erosion is one of the most common causes of failure in hydraulic engineering structures, such as embankments and levees. It also plays a vital role in the geohazards (such as landslides and sinkhole developments) and more importantly, the earth landscape evolution, which has a broad environmental and ecosystem impacts. The groundwater seepage is multi-directional, and its multi-dimensional nature could affect the initiation and the progression of internal erosion. With a newly developed apparatus, we carry out nine internal erosion experiments under five different seepage directions. The results reveal that the critical hydraulic gradient increases as the seepage direction varies from the horizontal to the vertical. After a global erosion is triggered, preferential erosion paths distribute randomly from the bottom to the top of the specimen. If the seepage direction is not vertical, small preferential erosion paths merge into a large erosion corridor, in which the loss of fine particles is significant but negligible outside. Results of experiments manifest that the erosion is heterogeneous and three-dimensional, even in the unidirectional seepage flow. The particles are rapidly eroded at the early stage of the erosion, indicating a high erosion rate. With the erosion time increasing, the particle loss slows down and even ceases if the time is long enough. The erosion rate increases if the seepage direction approaches a vertical direction. Overall, the erosion rate approximately decreases with erosion time exponentially. We proposed exponential equations to illustrate the variation of the erosion rate in the erosion process.

Gary Ghahremani

and 2 more

Summary Background: Torus is a protuberant and lobulated exostosis that develops on the lingual aspect of the jaws or hard palate in 10-30% of adults. They can interfere with mastication, speech, oral hygiene, and denture placement. Their enlargement with advancing age may also lead to superficial ulceration, inflammation, osteonecrosis and various other complications. Methods: A retrospective analysis of the authors’ experience with 17 adults who had large symptomatic tori was performed. The patients were examined by intraoral imaging and radiographic or computed tomography of their maxillofacial bones. Their dental and medical records were reviewed along with the pertinent literature concerning the prevalence and reported complications of this entity. Results: This series included 6 men and 11 women, ranging in age from 36 to 85 years (Mean age: 56.5 years).There were 6 patients with torus mandibularis, 8 with torus palatinus, and 3 with torus maxillaris. Four of our 17 patients required surgical excision of their tori because of large size, recurrent superficial erosions and associated symptoms. Conclusion: The majority of tori are asymptomatic and incidental finding, but the more prominent tori are prone to mucosal inflammation and ulceration that may require surgical removal of the lesion. Large tori can also interfere with mastication, speech, dental hygiene, placement and function of prosthetic dentures, and may cause snoring, sleep apnea or other complications. Therefore, the practicing physicians should be familiar with the appearance, radiological features, clinical implications and management of tori.

Wahaj Munir

and 3 more

Background: Acute type A aortic dissection (ATAAD), is a surgical emergency often requiring intervention on the aortic root. There is much controversy regarding root management; aggressively pursuing a root replacement, versus more conservative approaches to preserve native structures. Methods: Electronic database search we performed through PubMed, Embase, SCOPUS, google scholar and Cochrane identifying studies that reported on outcomes of surgical repair of ATAAD through either root preservation or replacement. The identified articles focused on short- and long-term mortalities, and rates of re-operation on the aortic root. Results: There remains controversy on replacing or preserving aortic root in ATAAD. Current evidence supports practice of both trends following an extensive decision-making framework, with conflicting series suggesting favourable results with both procedures as the approach that best defines higher survival rates and lower perioperative complications. Yet, the decision to perform either approach remains surgeon decision and bound to the extent of the dissection and tear entries in strong correlation with status of the aortic valve and involvement of coronaries in the dissection. Conclusions: There exists much controversy regarding fate of the aortic root in ATAAD. There are conflicting studies for impact of root replacement on mortality, whilst some study’s report no significant results at all. There is strong evidence regarding risk of re-operation being greater when root is not replaced. Majority of these studies are limited by the single centred, retrospective nature of these small sample sized cohorts, further hindered by potential of treatment bias.

Nicholas Hess

and 3 more

Background: This study compared outcomes of patients bridged with extracorporeal membrane oxygenation (ECMO) to orthotopic heart transplantation (OHT) following the recent heart allocation policy change. Methods: The United Network of Organ Sharing Registry (UNOS) database was queried to examine OHT patients between 2010-2020 that were bridged with ECMO. Waitlist outcomes and one-year posttransplant survival were compared between patients waitlisted and/or transplanted before and after the heart allocation policy change. Secondary outcomes included posttransplant stroke, renal failure, and one-year rejection. Results: 285 waitlisted patients were included, 173 (60.7%) waitlisted under the old policy and 112 (39.3%) under the new policy. New policy patients were more likely to receive OHT (82.2% vs 40.6%), and less likely to be removed from the waitlist due to death or clinical deterioration (15.0% vs 41.3%) (both P<0.001). 165 patients bridged from ECMO to OHT were analyzed, 72 (43.6%) transplanted during the old policy and 93 (56.3%) under the new. Median waitlist time was reduced under the new policy (4 days [IQR 2-6] vs 47 days [IQR 10-228]). Postoperative renal failure was higher in the new policy group (23% vs 6%; P=0.002), but rates of stroke and one-year acute rejection were equivalent. One-year survival was lower the new policy but was not significant (79.8% vs 90.3%; P=0.3917). Conclusions: The UNOS heart allocation policy change has resulted in decreased waitlist times and higher likelihood of transplant in patients supported with ECMO. Posttransplant one-year survival has remained comparable although absolute rates are lower.

Matthew Sussman

and 9 more

The recognition of fibrinolysis phenotypes in trauma patients has led to a reevaluation of antifibrinolytic therapy (AF). Many cardiac patients also receive AF, however the distribution of fibrinolytic phenotypes in that population is unknown. The purpose of this study was to fill that gap. Methods: Data were retrospectively reviewed from 78 cardiac surgery patients. Phenotypes were defined as hypofibrinolytic (LY30 <0.8%), physiologic (LY30 0.8-3.0%) and hyperfibrinolytic (LY30 >3%). Continuous variables were expressed as M ± SD or median (interquartile range). Results: The study population was 65±10 yrs old, 74% male, average body mass index of 29±5 kg/m2. Fibrinolytic phenotypes were distributed as physiologic=45%, hypo=32% and hyper = 23%. There was no obvious effect of age, gender, race, or ethnicity on the distribution of fibrinolysis phenotypes; 47% received AF. The time with chest tube during post-operative recovery was longer in those who received AF (4[3,5] days) vs no AF (3[2,4] days), P=0.037). All cause morbidity occurred in 51% of patients who received AF vs 25% with no AF (p=0.017). However, with AF vs no AF, apparent differences in median chest tube output (1379 vs 820ml, p=0.075), hospital LOS (13 vs 10 days, P=0.873), estimated blood loss (1100 vs 775 ml, P=0.127), units of transfused RBCs (4 vs 2], P=0.152) or all-cause mortality (5.4% [2/37] vs 10% [4/41], P=0.518) were not statistically significant. Conclusion: This is the first description of three distinctly different fibrinolytic phenotypes in cardiac surgery patients. In this population, the use of AF was associated with increased morbidity.

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