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Larger spatial scale decreases the magnitude of, but does not eliminate, the observed...
Audrey Arnal
Oscar Rico-Chávez

Audrey Arnal

and 7 more

June 09, 2020
Despite important implications for biological conservation and public health, the potential generality of a prophylactic effect of biodiversity on zoonotic pathogen transmission (e.g., dilution effect) remains hotly debated, potentially because existing studies focus on different kinds of analyses as well as different spatial scales. Here, we test if changing the spatial scale of analysis can affect the detection of a relationship between hantavirus infection prevalence and rodent species richness throughout the World. We found that these relationships are always negative, whatever the spatial scale. Nevertheless, the dilution effect magnitude decreases if larger spatial scales are considered. These results, which remain consistent for all regions, highlight that the dilution effect should be a general phenomenon for hantaviruses, but that its detection can be hampered by the spatial scale considered. Finally, we discuss the mechanisms that can hinder the observation of a dilution effect and the necessity to consider other host-pathogen systems.
The DEDO forest conservation culture a means to conserves the Ororo (Ekebergia capens...
Getaneh Haile

getaneh Haile

June 09, 2020
The forest people around the world through their indigenous knowledge contribute to the sustainable management of forests. This article argues that the Sheka people in southwestern Ethiopia by their ecological knowledge, values, and spiritual use could manage the Ororo tree (Ekebergia capensis). The Ororo tree (Ekebergia capensis) is one of the most important endemic tree species in the Sheka zone southwestern Ethiopia and, at the same time, one of the most endangered species. Data collected on the indigenous ecological knowledge of the Sheka people and how the Ororo tree could be managed and conserved through the DEDO culture documented and the spiritual connection between the Ororo trees and the Sheka people traditional belief system measured. The findings revealed that through their traditional forest-related knowledge, the Sheka people conserve and manage a single larger tree called Ororo. The Ororo tree is a special type of tree that has cultural and spiritual attachments that are presently non-existent. This unique forest conservation practice has been referred to as the DEDO culture. The culture of DEDO comes up with worshiping around the Ororo tree. Thus, the culture of DEDO played an important role in maintaining the conservation of the DEDO sacred tree (Ororo) and biodiversity therein. Over time, the DEDO sacred tree (Ororo) conservation culture has been decline, and various factors have contributed to the decline of this useful ecological knowledge.
Engaging students through online video homework assignments: A case study in a large-...
Laci Gerhart
Brittany Anderton

Laci Gerhart

and 1 more

June 10, 2020
Online educational videos have the potential to enhance undergraduate biology learning, for example by showcasing contemporary scientific research and providing content coverage. Here, we describe the integration of nine videos into a large-enrollment introductory evolution and ecology course via weekly homework assignments. We predicted that videos that feature research stories from contemporary scientists could reinforce topics introduced in lecture and provide students with novel insights into the nature of scientific research. Using qualitative analysis of open-ended written feedback from the students on each video assigned throughout the term (n=133-229 responses per video), we identified ten common themes in student perspectives. On the whole, the video homework assignments received more positive than negative comments and all videos received comments suggesting that they were engaging and contributed to learning goals. We discuss opportunities and challenges for the use of online educational videos in teaching ecology and evolution, and we provide guidelines instructors can use to integrate them into their courses.
When were clinicians ever not competent?
Mathew Mercuri

Mathew Mercuri

June 09, 2020
Competence based education (CBE) has become increasingly popular as of late among health professions training programs. Models of CBE have been developed and implemented by major licensing bodies and professional Colleges (and affiliated education programs), such as the Royal College of Physicians and Surgeons of Canada (RCPSC) and the Association of American Medical Colleges (AAMC). In this month’s issue of theJournal of Evaluation in Clinical Practice , several studies describe an experience with designing and implementing a CBE model [1-6]. On the surface, the desire to ensure that health professions trainees are competent is commendable – just as it is likely few would argue that the care they receive should not be evidence based, I suspect that few (if any) would be comfortable with the clinician prescribing or managing said care being less than competent. However, the notion of a need for a CBE model might suggest that there was some issue with competence in the training of past clinicians that needed remedy, i.e. there is a lack of competence among some clinicians entering their profession that is in part a product of their training.When considering public perception of clinician competence, that of physicians in particular, history is not kind. Over the past two millennia, medicine got it wrong more often than right – humoral theory, bloodletting, miasma and contagion were all highly subscribed among the healthcare community but are now relics of a bygone era. In fact, the poor track record of medicine was the basis for a need for evidence based medicine (EBM). Practitioners of healthcare were often portrayed as ineffective, as providing little more than palliative support while nature took its course for better or worse, or even crueler, as charlatans peddling nostrums [7]. Artists were no kinder to clinicians. For example, Shaw’s The Doctors Dilemma portrays a group of physicians as self-absorbed, greedy, overly confident in their unproven (and presumably, ineffective) pet “cures”, with only the poorest among them as having any sense of humility and patient centred focus in his practice [8]. It seems that only within the last century did clinicians develop a good public reputation, much of which might be more appropriately attributed to improvements in hygiene practices/standards of living at a societal level (e.g. the McKeown Thesis[9]) or likewise to medical science and the discovery of “silver bullet” cures (e.g. antibiotics, insulin, etc.) rather than to a change in how clinicians approached the learning of their craft and care of their patients. However, a historical lack of curative success and a poor reputation does not entail a lack of competence. A clinician working in Europe during the first millennium of the Common Era would have been considered competent provided he (or much rarer, she) mastered humoralism according to the teachings of Galen. Is it possible that future generations will look at the clinicians of today – even those who train under CBE – in the same light as we do clinicians of the past? Should a failure of today’s medicine in the eyes of future generations invalidate the competence of contemporary clinicians? I suppose the impact of the answer to such questions on the issue of competence hinges on how we define (and measure) competence.What then makes a clinician competent? The obvious answer is technical knowledge in the clinician’s given area. By that, I assume that for a clinician to be considered competent, she requires a minimum understanding of the content and technique of her given profession contemporaneous with the period of practice.11A minimum understanding of content and technique is required to be accepted into the profession, but it is not the desirable end. Clinicians are expected to participate in a model of lifelong learning with a goal of mastery over that content and technique. However, knowledge might be considered the minimum requirement. Several frameworks of competence outline additional requirements. For example, the “CanMEDS” framework, issued by the RCPSC, identifies “the abilities physicians require to effectively meet the health care needs of the people they serve”22http://www.royalcollege.ca/rcsite/canmeds/canmeds-framework-e, accessed on June 8, 2020., which includes the roles of the physician as medical expert, communicator, collaborator, leader, health advocate, scholar, and professional. The criteria by which these “roles” were selected (and other “roles” excluded), including the theoretical and/or empirical justification for their inclusion as part of “competence” is not clear to me, nor is it entirely clear if available metrics are sufficient in demonstrating that the roles have in fact been achieved by the trainee or how one operationalizes those roles in practice. Are clinicians who lack ability in any of these “roles” incompetent? Does meeting all of them according to some threshold ensure competence? As health professions are typically self-regulating, it is up to the governing bodies of each profession to decide, which might suggest that competence is a product of the times rather than akin to a “natural kind”33If it is the case that “competence” in medical practice, for example, is in fact a standard set by the profession (which I think most people would agree is the case), then judging the competence of past or future physicians by the current standard might be inappropriate. That raises issues about differing standards of competency for currently practicing physicians who trained at different times. In Canada, we are currently going through a transition whereby our training programs have two cohorts – one that is training under the previous “time based” model and the other under the current “competence by design” model. Is it the case that there is a relatively less (or no) guarantee that those training under the previous model are competent? The answer to that question might impact the extent to which we should have confidence in currently practicing clinicians, or at least relative to the next generation. Regardless, all practicing clinicians are accountable to a standard set by their respective professional Colleges, which likely makes the issue moot once trainees enter independent practice..It would be silly to suggest that clinicians who trained under a pre-CBE model are not competent any more than it is to suggest that clinical decisions prior to the adoption of the EBM movement were not based on evidence. Certainly, we have no shortage of competent clinicians practicing today. Those clinicians were accepted into the profession (and maintain standing) on some assessment of competence. However, institutions may have good reason for implementing CBE beyond simple competence concerns. For example, CBE programs can facilitate the development of an infrastructure of accountability that extends beyond activities of remediation or accelerating advancement to independent practice. That infrastructure can be leveraged to ensure transparency in assessment and advancement, identify individualized training needs, etc. that can be important components of ensuring and achieving equitable access to health professions, particularly for traditionally underrepresented populations.44It is important to note that while CBE might drive the development of such an infrastructure, a CBE training model is not necessary to do so. Certainly, institutions can and should be striving to improve on accountability, equitable access, etc., irrespective of a CBE model.On the other hand, we have no shortage of experience with poor decisions, suboptimal patient outcomes, iatrogenic effects, etc., that often raise concern about clinician ability (or competence). Poor outcomes, or at least those not aligned with the expectations of the public (irrespective of if those expectations are realistic) could be construed by some as a result of incompetence. Likewise, inequitable access (within or between communities) to appropriate expertise might raise concern of a lack of professional competence (i.e. the profession is not meeting the needs of the population inclusively). One way such perceptions by the public can be problematic for healthcare professions is that may erode the powerful position of institutionalized healthcare (and its providers) that exists in many societies. One could argue that EBM had a powerful effect on securing the public’s trust in healthcare by leveraging public perception of science as apolitical, objective, etc. Does CBE play a similar role by highlighting high professional standards only achievable by those “worthy” of the profession, who were rigorously assessed using quantifiable (often presented as “objective”) metrics, irrespective of whether that results in better care for patients? If so, then CBE may constitute a political move to retain or grow power rather than a remedial exercise to ensure no one joins the profession without having the skills necessary to provide appropriate care (by some defined public standard) for those seeking service. In other words, one might argue that CBE is not a response to a concern about competence – it is a response to a potential loss of standing relative to alternative modes of care or other social services. I am not suggesting that is necessarily the case, as I know several health professions educators who are honest in their pursuit to train clinicians who will excel in serving and providing care for the community. That seems to be the rule rather than the exception. However, the goals of the educators may not always tightly align with the goals of the institution, which may also be responsible for securing funding, maintaining status, public accountability, etc.Models of health professions training that focus on assessing and achieving defined competencies rather than hoping that important abilities are acquired over a defined time period (that also relies on the reliability and validity of licensing exams) are admirable. It is difficult to argue that achieving competence should not be the explicit focus of training. Perhaps one of the greatest benefits of CBE is that it puts competence to the forefront, just as EBM did for evidence. However, we must be vigilant to ensure that “competence” stays more than a buzzword or a tool of branding. Terms lacking substance can have a negative effect on patient care – too often the terms “patient centred” and “evidence based”, for example, are invoked as placeholders for quality patient care without any evidence to support that whatever intervention or program those terms are describing has any positive impact beyond rhetorical. We have not entered into an era of clinician competence simply because CBE has been implemented. Rather, what I see as the greatest benefit of CBE is the opportunity for improving and ensuring accountability.ReferencesRich J, Young SF, Donnelly C, et al. Competency-based education calls for programmatic assessment: But what does this look like in practice? Journal of Evaluation in Clinical Practice 2020;26(4):Hamza DM, Ross S, Oandasan I. Process and outcome evaluation of a CBME intervention guided by program theory. Journal of Evaluation in Clinical Practice 2020;26(4):Egan R, Chaplin T, Szulewski A, et al. A case for feedback and monitoring assessment in competency-based medical education. Journal of Evaluation in Clinical Practice 2020;26(4):Katoue MG, Schwinghammer TL. Competency-based education in pharmacy: A review of its development, applications, and challenges. Journal of Evaluation in Clinical Practice 2020;26(4):Crawford L, Cofie N, McEwen L, Dagnone D, Taylor SW. Perceptions and barriers to competency-based education in Canadian postgraduate medical education. Journal of Evaluation in Clinical Practice 2020;26(4):Railer J, Stockley D, Flynn L, Hastings-Truelove A, Hussain A. Using outcome harvesting: Assessing the efficacy of CBME Implementation. Journal of Evaluation in Clinical Practice 2020;26(4):Porter R. The Greatest Benefit to Mankind: A Medical History of Humanity. New York: W.W. Norton & Company; 1997.Shaw, B. The Doctor’s Dilemma: A Tragedy. London: Constable and Co.; 1922.McKeown T. The role of medicine: Dream, mirage or nemesis? Nuffield Trust; 1976. Available at: https://www.nuffieldtrust.org.uk/files/2017-01/1485273106_the-role-of-medicine-web-final.pdf. Accessed on June 8, 2020.
COVID 19 : ETHICAL DILEMMAS IN HUMAN LIVES
Smadar Bustan
Mirco Nacoti

Smadar Bustan

and 7 more

June 09, 2020
The outbreak of the Covid-19 pandemic obliged us all to handle many dilemmas, some of which we took upon ourselves as philosophers, ethicists, doctors and nurses to discuss around four key ethical notions : responsibility, dignity, fairness and honouring death. The following collection of the symposium acts held online in May 2020 with the Paris Global Center of Columbia University and Columbia Global Centers, attempts to testify to the ongoing pandemic emergency and difficult challenges while evaluating whether the ethical principles in the official recommendations were able to meet the lived reality. Looking at accountability and consistency in regard to the context of exercise, it seemed equally important to examine, through an international exchange, whether the contextuality of Coronavirus across countries and cultures affected the ethical decision making processes. We hope that our discussion can serve as a resource for advanced care planning, helping medical providers and other specialists to consider the shared important aspects of medical ethics in times of great uncertainty.
Impact of constipation on atopic dermatitis: A nationwide population-based cohort stu...
Yen Chu Huang
Meng-Che Wu

Yen Chu Huang

and 3 more

June 09, 2020
Atopic dermatitis (AD) is the chronic relapsing inflammatory skin disorder that affects both in childhood and adulthood. Mounting evidence indicates that gut dysbiosis contributes to AD via the gut-skin axis. Constipation could result in alteration of the gut microflora. The clinical impact of constipation on AD has not been researched. Therefore, we aim to assess the risk of AD in constipated patients by the longitudinal nationwide population-based cohort study. We collected 87015 people with constipation and 87015 patients without constipation between 1999 and 2013 from the Longitudinal Health Insurance Database, which is the subset of Taiwanese National Health Insurance Research Database. Propensity score analysis was administrated to match age, gender, comorbidities, and medications at a ratio of 1:1. Multiple Cox regression analysis was utilized to evaluate the adjusted hazard ratio of AD. In addition, sensitivity tests and a stratified analysis were conducted. The incidence of AD was 4.7 per 1,000 person-years in the constipation group, which was higher than the rate of 2.2 per 1,000 person-years observed in the non-constipation group. After adjustment for age, gender, comorbidities, corticosteroids, and antihistamine, people with constipation had a 2.11-fold greater risk of AD compared to those without constipation (adjusted hazard ratio [aHR]: 2.11 (95% C.I. 1.98-2.24). In subgroup analyses, people aged 12-19 years had a 2.34-fold higher risk of AD in the constipation cohort (aHR; 95% CI, 1.84-2.98). Moreover, people with constipation had a higher likelihood of AD, regardless of gender, and with or without comorbidities, as well as the usage of corticosteroids, and antihistamines. Constipation is connected with a significantly risk factor of AD. Clinicians should be careful of the possibility of AD in people with constipation. Further study is warranted to investigate the possible pathological mechanisms of underlying this relationship.
Soil Carbon Stock and soil physico-chemical properties under A.saligna plantation in...
Mulat Assefa
Emiru Birhane

Mulat Assefa

and 4 more

June 09, 2020
Afforestation of degraded lands using both exotic and indigenous species is used to reduce land degradation and to reforest degraded areas. Acacia saligna is one of the common exotic plantation species planted in Ethiopia. This study analyzed the existing carbon stock and some soil physico-chemical properties of A. saligna plantation at two districts in Tigray, northern Ethiopia. Soil samples were collected from 204 samples at three soil depths from plantation site and adjacent grazing lands. Paired t-test was used to analyze data. Soil organic carbon (SOC) stock was higher at lower depth (40-60cm) than middle and upper depths at plantation sites while the second depth (20-40cm) was found higher SOC at grazing lands. Furthermore, in Mai-Brazio, soil properties except Total nitrogen(TN) and Available Phosphorus (Av,P), Cation Exchange Capacity (CEC), Available Potassium (Av,K) and soil pH were significantly (P<0.05) higher than adjacent grazing lands While CEC and Av.K were non-significant in Barka-Adisbha site (p>0.05). Area converted to plantation site showed lower soil bulk density than the open grazing land. Further, CEC is negatively correlated (P < 0.001) with soil pH, this may shows that CEC is affected by the variation of soil pH.
Fine-scale variation within urban landscapes affects marking patterns and gastrointes...
Lisa Gecchele
Amy Pedersen

Lisa Gecchele

and 2 more

June 09, 2020
1. Urban areas are often considered to be a hostile environment for wildlife as they are highly fragmented and frequently disturbed. However, these same habitats can contain abundant resources, while lacking many common competitors and predators. The urban environment can have a direct impact on the species living there, but can also have indirect effects on their parasites and pathogens. To date, relatively few studies have measured how fine-scale spatial heterogeneity within urban landscapes can affect parasite transmission and persistence. 2. Here we surveyed 237 greenspaces across the urban environment of Edinburgh (UK) to investigate how fine-scale variation in socio-economic and ecological variables can affect red fox (Vulpes vulpes) marking behaviour, gastrointestinal (GI) parasite prevalence and parasite community diversity, 3. We found that the presence and abundance of red fox faecal markings was non-uniformly distributed across greenspaces, and instead was dependent on the ecological characteristics of a site. Specifically, common foraging areas were left largely unmarked, which indicates that suitable resting and denning sites may be limiting factor in urban environments. In addition, the amount of greenspace around each site was positively correlated with overall GI parasite prevalence, species richness and diversity, highlighting the importance of greenspace (a commonly used measure of landscape connectivity) in determining the composition of the parasite community in urban areas. 4. Our results suggest that fine scale variation within urban environments can be important for understanding the ecology of infectious diseases in urban wildlife and could have wider implication for the management of urban carnivores.
Renin-Angiotensin-Aldosterone-System Blocking Drugs in Patients with SARS-CoV-2 - Sys...
Chang Chu
Shufei Zeng

Chang Chu

and 5 more

June 09, 2020
Background and Purpose: COVID-19 patients treated with RAAS blockers are among the patients at highest risk of poor outcome. ACE2 is the functional receptor for SARS-CoV-2. Animal studies suggest that RAAS blockers might increase the expression of ACE2 and potentially increase the risk of SARS-Cov-2 infection. Experimental Approach and Key Results: The effect of ACE inhibitor treatment on the incidence of pneumonia in non-COVID-19 patients was analyzed in 25 studies (330,780 patients). ACE inhibitor use was associated with a 27% reduction of pneumonia risk (OR: 0.73, p<0.001). Pneumonia related death cases in ACE inhibitor treated non-COVID-19 patients were reduced by 27% (OR: 0.73, p=0.004). ARB treatment was analyzed in 10 studies (275,621 non-COVID-19 patients). The risk of pneumonia was not different between patients who did or did not use ARBs. Pooled results from 16 studies in 22,333 COVID-19 patients showed that COVID-19 related server adverse clinical outcomes (admission to ICU, need for assisted ventilation or death) were reduced by 26% when using RAAS blocking agents (OR=0.74, p=0.04). Pooled results from 10 studies in 11,514 COVID-19 patients showed that RAAS blockede reduces all-cause mortality by 41% (OR=0.59, p=0.01). Conclusion and Implications: Given the weak evidence coming from animal studies and the clear beneficial data of ACE inhibition in non-COVID-19 patients and the promising data in COVID-19 patients, the use of RAAS blocking agents in patients with SARS-CoV-2 infection is justified and should be maintained. Further clinical studies analysing ARBs and ACE inhibitors separately in COVID-19 patients are needed.
COVID-19 relapse: a diagnostic predicament for clinicians
Shramana Deb
Gourav Shome

Shramana Deb

and 3 more

June 09, 2020
Abstract- The ongoing outbreak of COVID-19 that began in Wuhan, China, has constituted a Public Health Emergency of International Concern, with cases confirmed in more than 200 countries. Currently, infected individuals are the primary source of infection and multiple cases of relapse are also reported following the recovery. It is highly concerning about the nature of relapse which may be caused due to reactivation or reinfection. While the present testing scenario of using different molecular techniques has several loop holes that can report false results and hamper the process of effectively preventing the transmission of the virus. Various recommendations need modifications as to effectively stop the horizontal transmission of the virus and look deeply into the links with relapse cases to prevent a second wave during a pandemic.
Which factors can influence the number of forced expiratory maneuvers on spirometry i...
Rafaela Minsky

Rafaela Minsky

June 09, 2020
Introduction: Spirometry is of great value for understanding respiratory function and management of lung diseases. However, it presents special challenges when performed in children. Objective: To analyze factors that may influence the number of forced expiratory maneuvers required for successful spirometry in schoolchildren. Method: Healthy children aged between 6 and 12 years were tested. Forced spirometry maneuvers were conducted according to the American Thoracic Society. The children were grouped according to the number of attempts (maximum of eight). Factors that potentially influenced the number of maneuvers included: age; pulse oscillometry parameters; slow vital capacity; respiratory muscle strength; orofacial motor function, school performance, physical activity and quality of life. The Kolmogorov-Smirnov test was performed, followed by the Chi-Square, repeated measures ANOVA and Kruskal-Wallis tests. Next, multinomial logistic regression was applied. Significance level was set at 5%. Results: 149 children (80 girls) with mean age of 9.13 years (± 1.98) were studied. Age was related to the required number of spirometry maneuvers and children with poor school performance had a 2.84- fold greater chance of completing the exam in more than five attempts. Conclusion: Age and school performance influenced the number of forced expiratory maneuvers required for successful spirometry in schoolchildren.
The Rapid Developed Ovarian Krukenberg Tumors after Ovarian Hyperstimulation: a Case...
Shu Zhu
Xia Wang

Shu Zhu

and 5 more

June 09, 2020
A document by Shu Zhu. Click on the document to view its contents.
Measurement of Pain and Related Symptoms in Irritable Bowel Syndrome
Affifa Farrukh

Affifa Farrukh

June 09, 2020
This paper reviews the tools available to assess outcomes of treatment in irritable bowel syndrome, especially the effect on pain. It critically considers their development, relevance and reliability. Its conclusion is that there are few tools which meet the criteria necessary to place confidence in their validity as appropriate measures of patient outcomes.
From cell line engineering to the formulated drug product: The art of manufacturing t...
Stefania Carrara
Michael Ulitzka

Stefania Carrara

and 5 more

June 09, 2020
Therapeutic monoclonal antibodies and related products have steadily grown to become the dominant product class within the biopharmaceutical market. Production of antibodies requires special precautions to ensure safety and efficacy of the product. In particular, minimizing antibody product heterogeneity is crucial as drug substance variants may impair the activity, efficacy, safety and pharmacokinetic properties of an antibody, consequently resulting in the failure of a product in pre-clinical and clinical development. This review will cover the manufacturing and formulation challenges and advances of therapeutic monoclonal antibodies, with a focus on improved processes to minimize variants and ensure batch-to-batch consistency. Processes put in place by regulatory agencies such as Quality-by-Design (QbD) and current Good Manufacturing Practices (cGMP) will be reviewed, and how their implementation has aided drug development in pharmaceutical companies. Advances in formulation and considerations on the intended use of a therapeutic antibody, including route of administration and patient compliance, will be discussed.
CFD-DEM modelling of biofilm streamers oscillations and their interactions in the flo...
YUQING XIA
Pahala Jayathilake

YUQING XIA

and 4 more

June 09, 2020
Biofilm streamer motion under different flow conditions is important for a wide range of industries. The existing work has largely focused on experimental characterisations of these streamers, which is often time-consuming and expensive. To better understand the physics of biofilm streamer oscillation and their interactions in fluid flow, a CFD-DEM (Computational Fluid Dynamics – Discrete Element Method) model has been developed. The model was used to study the flow-induced oscillations of single and multiple biofilm streamers. We have studied the effect of streamer length on the oscillation at varied flow rates. The predicted single biofilm streamer oscillations in various flow rates agreed well with experimental measurements. Furthermore, we have investigated the effect of the spatial arrangement of streamers on interactions between two oscillating streamers, which have not been achieved previously.
Increasing Production of Engineered Cells in Multiple Myeloma Using Microfluidic Tech...
arezoo karamivandishi
Masoud Soleimani

arezoo karamivandishi

and 2 more

June 09, 2020
The potential use of gene- modified cell therapy in hematologic malignancies is often limited by complications related to effectively engineering and manufacturing cells with conventional delivery systems and is challenge specifically for immune cells. In fact, this life-saving therapy requires use of inefficient reagents and specialized equipment that can drive up the price of the treatment. Herein, we compared two different approaches for gene transfer into target cells: Nucleofection as a 2D gene delivery and microfluidic device as a 3D gene transfer technology. In fact, we developed and used serpentine microfluidic chip for cell membrane penetration that permits delivery of DNA into Multiple myeloma cells. We achieved high transfection efficiency (55.7% GFP) in myeloma cells with high cell viability (by PI staining) 24-48 hours after microfluidic processing compared to nucleofection that is toxic and rate of dead cells is very high. The significant differences in outcomes from the two techniques underscores the importance of understanding the impact of intracellular delivery techniques on cell function for research and clinical applications. Altogether, these results highlight the use of microfluidic device as a rapid and gentle delivery method with promising potential to engineer primary human cells for research and clinical applications.
Agenesis of Inferior Vena cava in complicated by recurrent Deep venous thrombosis and...
Mohammed Elfaki
Asma   Abdallah

Mohammed Elfaki

and 2 more

June 09, 2020
A 47 year-old man who was successfully treated for PE . later on Discovered to have left sided venous engorgement in the abdomen and left lower limb . He was later discovered to have congenital absence of inferior vena cava and was prepared for investigations including venography and coagulation profile
RETRIEVAL OF FRAGMENTED PERIPHERALLY INSERTED CENTRAL CATHETER (PICC) WITH A DOUBLE T...
Alfonso Papa
Dario Tammaro

Alfonso Papa

and 2 more

June 09, 2020
Retrieval of central venous catheters fragments often puts us in front of different situations. Having more techniques available for strategic planning of the procedure is imporatnt. The authors propose the simultaneous use of two different approaches for the recovery of a CVC fragment from the pulmonary artery.
LATE CLINICAL PRESENTATION OF HYPOPLASTIC LEFT HEART SYNDROME
İbrahim Demir
Alper Ucak

İbrahim Demir

and 3 more

June 09, 2020
Hypoplastic left heart syndrome (HLHS) is an important reason of deaths due to congenital heart diseases in newborns. The first step of palliative operations is generally performed between the first few days and two weeks of their lives to ensure circulatory balance. Patients not treated early are fatal. However, there are patients who can survive without surgical intervention. As in our 2-year-old patient with no growth retardation; protective mechanisms such as widely patent ductus arteriosus, adequate coronary circulation, restrictive atrial septal defect (ASD), normal pulmonary venous return and no significant arterial obstruction can make this possible.
20-Year Survival Following Orthotopic Heart Transplantation in the United States
Nicholas Hess
Laura Seese

Nicholas Hess

and 6 more

June 09, 2020
Background: This study evaluated 20-year survival following adult orthotopic heart transplantation (OHT). Methods: The United Network of Organ Sharing Registry database was queried to study adult OHT recipients between 1987-1998 with over 20-year posttransplant follow-up. The primary and secondary outcomes were 20-year survival and cause of death following OHT, respectively. Multivariable logistic regression was used to identify significant independent predictors of long-term survival, and long-term survival was compared among cohorts stratified by number of predictors using Kaplan Meier survival analysis. Results: 20,658 patients undergoing OHT were included, with median follow-up of 9.0 (IQR 3.2-15.4) years. Kaplan-Meier estimates of 10-, 15-, and 20-year survival were 50.2%, 30.1%, and 17.2%, respectively. Median survival was 10.1 (IQR 3.9-16.9) years. Increasing recipient age (>65 years), increasing donor age (>40 years), increasing recipient BMI (>30), black race, ischemic cardiomyopathy, and longer cold ischemic time (>4 hours) were adversely associated with 20-year survival. Of these 6 negative predictors, presence of 0 risk factors had the greatest 10-year (59.7%) and 20-year survival (26.2%), with decreasing survival with additional negative predictors. The most common cause of death in 20-year survivors was renal, liver, and/or multisystem organ failure whereas graft failure more greatly impacted earlier mortality. Conclusions: This study identifies six negative preoperative predictors of 20-year survival with 20-year survival rates exceeding 25% in the absence of these factors. These data highlight the potential for very long-term survival following OHT in patients with end-stage heart failure and may be useful for patient selection and prognostication.
Ophthalmic examination of heterotopic bone formation in guinea pig: A case report
SO GOTO
Qiurong Zhu

SO GOTO

and 4 more

June 09, 2020
Two different types of ophthalmic optical coherence tomography (OCT) imaging were used to evaluate ocular health in a guinea pig suspected of having heterotopic bone formation (HBF). Captured images facilitated diagnosis of HBF. This case report provides reference OCT images of HBF in the guinea pig.
Vaginal support pessary in treatment of rectal prolapse Case series and review
Myriam Girgis
Joseph Lee

Myriam Girgis

and 2 more

June 09, 2020
Rectal prolapse is a pelvic floor disorder that involves descent of full or partial thickness rectum through anus. The novel use of a vaginal support pessary may avoid surgery in those who are not fit for surgery or prefer to avoid surgery, and may provide temporary relief whilst awaiting surgery.
Rational design of 0D Mn0.05Cd0.95S anchored on 3D NiSe2 nanoparticles for efficient...
Hua Liu
Teng Yan

Hua Liu

and 3 more

June 08, 2020
A novel effective 0D/3D nanohybrids of Mn0.05Cd0.95S/NiSe2 photocatalysts, which are formed by Mn0.05Cd0.95S nanoparticles anchored on the outer surface of cubic NiSe2 in designed and prepared. The optimum hydrogen evolution rate of the Mn0.05Cd0.95S/NiSe2 composite is 14.3 mmol h-1 g-1, which is 7.5 times higher than that of single Mn0.05Cd0.95S. Structural analyses and experimental results reveal that a little amount of NiSe2 can remarkably improve the photocatalytic activity and the close contact of the 0D/3D composite catalyst also plays an important role. Furthermore, NiSe2 can not only as both an electron acceptor to capture electrons and inhibit the recombination of electron-hole pairs, but also provide sufficient active sites to facilitate the photocatalytic water-splitting reaction activity. This work demonstrates that low-cost NiSe2 is a promising co-catalyst for photocatalytic splitting of water to produce hydrogen.
Mathematical modelling of reaction-separation in an enzymatic membrane reactor during...
Xianhui Li
Ziran Su

Xianhui Li

and 4 more

June 08, 2020
Process analysis and optimization of an EMR system used for producing oligodextran are critical to improving EMR operating stability and cost effectiveness. We developed a mathematical model to evaluate the effects of operating conditions and membrane properties on the reaction-separation behavior of an EMR. Our analysis shows that tailoring a membrane with large porosity and uniform pore size distribution can simultaneously improve product quality and production efficiency. The optimum parameters of operating pressure and agitation speed depend on the selection of operating mode. A higher operating pressure was preferable for increasing the production efficiency of the EMR system under a water feeding mode. However, since the membrane suffered more severe fouling under a substrate feeding mode, extensive agitation was required to inhibit membrane fouling and enhance production yield. Our work paves the way for a new approach towards design of highly effective and low-consumptive EMR systems for oligodextran productio
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