35 research outputs found
Effects of Antioxidant Supplements on the Survival and Differentiation of Stem Cells
Although physiological levels of reactive oxygen species (ROS) are required to maintain the self-renewal capacity of stem cells, elevated ROS levels can induce chromosomal aberrations, mitochondrial DNA damage, and defective stem cell differentiation. Over the past decade, several studies have shown that antioxidants can not only mitigate oxidative stress and improve stem cell survival but also affect the potency and differentiation of these cells. Further beneficial effects of antioxidants include increasing genomic stability, improving the adhesion of stem cells to culture media, and enabling researchers to manipulate stem cell proliferation by using different doses of antioxidants. These findings can have several clinical implications, such as improving neurogenesis in patients with stroke and neurodegenerative diseases, as well as improving the regeneration of infarcted myocardial tissue and the banking of spermatogonial stem cells. This article reviews the cellular and molecular effects of antioxidant supplementation to cultured or transplanted stem cells and draws up recommendations for further research in this area
Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries
Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
"I can speak for myself." : #whitewednesdays, Iranian feminism, and hijab in media discourse
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] In December 2017, Viva Movahed stood on top of a utility box in Tehran with her hijab tied to an end of a stick in protest against Iran's compulsory hijab law. Movahed's actions initiated the campaign #WhiteWednesdays on Twitter, inspiring a global movement challenging hegemonic discourses on women, hijab, and the freedom of choice. This dissertation examines the mediated dialogue related to #WhiteWednesdays, particularly between U.S. mainstream news narrative and Iranian activists on Twitter. Specifically, this dissertation explores how hierarchies of visibility in both news and social media discourse can overshadow transnational feminist politics while reinforcing femonationalist narratives. Such discourses seemingly support women in Iran but simultaneously promote Islamophobic messages aligned with U.S. geopolitical politics. A critical discourse analysis of the #WhiteWednesdays campaign on Twitter and mainstream U.S. news coverage of the movement complicates representations of Iran, Muslim women, and feminist politics. Furthermore, this study unpacks the politics of representation, where certain voices on the ground are obscured in favor of elite sources who re-affirm U.S.-based Islamophobic and xenophobic ideologies
The Effect of Depakin Physiologically and Histology on the Kidney of Pregnant Female White Rats and the Investigation of the Protective Role of the Portulacea Oleracea Plant
Aim: Knowledge of histological and physiological changes of the kidneys in female rats treated with lepipakine, and the possible protective role of the use of Portulacea Oleracea plant extract.
Materials and Methods: Female rats were divided into six groups (1) control group (2) treatment group with therapeutic dose (0.5mg/kg), depakine (3) double dose treatment group (1mg/kg) of depakine.(4) Portulacea Oleracea -aqueous extract group at 2mg/kg, (5) therapeutic dose of depakine (0.5mg/kg) with Portulacea Oleracea -aqueous extract (2mg/kg), (6) double dose of depakine (1mg/kg) with Portulacea Oleracea -aqueous extract (2mg/kg) Any day for 18 days, and the female rats were dissected on the 19th day of pregnancy, and the kidneys were taken for histological examination and blood was drawn from the heart for urea and creatinine tests.
Results: Laboratory examination of kidney function showed a significant difference P001, where high urea and creatine were observed in the two groups treated with depakine with different dose concentrations, and the aqueous extract of the Portulacea Oleracea plant showed its protective role in reducing creatine and urea levels as shown in the table(1-1). The histological examination showed that Depakin led to histological changes in the kidneys of the therapeutic and double dose group of the drug, which was represented by atrophy in the glomerulus, hemorrhage within the tissue area and the appearance of a plug in the tubules in addition to thickening in the vessel as shown in the picture (A, B, C). Compared to the control group . As for the plant extract, the Portulacea Oleracea contributed to reducing the negative effects of the drug as shown in the pictures (E, F, G).
Conclusion: The drug led to many histological and physiological changes in the kidneys, and the aqueous extract of the Portulacea Oleracea plant also contributed to improving the kidney injury caused by the drug by reducing urea and creatinine levels, and reducing renal histological damage
MINTED: Multicast virtual network embedding in cloud data centers with delay constraints
Network virtualization is regarded as the pillar of cloud computing, enabling the multi-tenancy concept where multiple Virtual Networks (VNs) can cohabit the same substrate network. With network virtualization, the problem of allocating resources to the various tenants, commonly known as the Virtual Network Embedding problem, emerges as a challenge. Its NP-Hard nature has drawn a lot of attention from the research community, many of which however overlooked the type of communication that a given VN may exhibit, assuming that they all exhibit a one-to-one (unicast) communication only. In this paper, we motivate the importance of characterizing the mode of communication in VN requests, and we focus our attention on the problem of embedding VNs with a one-to-many (multicast) communication mode. Throughout this paper, we highlight the unique properties of multicast VNs and its distinct Quality of Service (QoS) requirements, most notably the end-delay and delay-variation constraints for delay-sensitive multicast services. Further, we showcase the limitations of handling a multicast VN as unicast. To this extent, we formally define the VNE problem for Multicast VNs (MVNs) and prove its NP-Hard nature. We propose two novel approach to solve the Multicast VNE (MVNE) problem with end-delay and delay variation constraints: A 3-Step MVNE technique, and a Tabu-Search algorithm. We motivate the intuition behind our proposed embedding techniques, and provide a competitive analysis of our suggested approaches over multiple metrics and against other embedding heuristics. 1972-2012 IEEE.Scopu
Traffic engineering in cloud data centers: A column generation approach
While many have advocated for the use of Virtual Local Area Networks (VLANs) as a way to provide scalable traffic management, finding the optimal traffic split (mapping) among VLANs to achieve load balancing has turned out to be a very challenging and combinatorially complex problem to solve. This paper considers the traffic engineering problem in data center networks by studying the joint problem of finding spanning trees for VLANs and optimally selecting the most promising spanning trees to map the traffic flows onto. We mathematically model this problem using Integer Linear Program (ILP) techniques and follow a primal-dual decomposition approach, using column generation, to solve exactly a relaxed mapping version of the problem, as well we present approximate solutions to the original problem. We show through numerical evaluations an outstanding scalability of the decomposed version of the problem and we use our results to study the performance of traffic engineering protocols developed in recent literature for data center networks.NPRP 5-137-2-045 grant from the Qatar National Research Fund (a member of the Qatar Foundation).Scopu
Optimal Polynomial Time Algorithm for Restoring Multicast Cloud Services
The failure-prone nature of data center networks has evoked countless contributions to develop proactive and reactive countermeasures. Yet, most of these techniques were developed with unicast services in mind. When in fact, multiple services hosted in data center networks today rely on multicast communication to disseminate traffic. Hence, the existing survivability schemes fail to cater to the distinctive properties and quality of service requirements that multicast services entail. This letter is devoted to understanding the ramifications of facility node or substrate link failure on multicast services residing in cloud networks. We formally define the multicast virtual network restoration problem and prove its NP-complete nature in arbitrary graphs. Furthermore, we prove that the problem can be solved in polynomial-time in multi-rooted treelike data center network topologies. 2016 IEEE.Scopu
Towards scalable traffic management in cloud data centers
Cloud Computing is becoming a mainstream paradigm, as organizations, large and small, begin to harness its benefits. This novel technology brings new challenges, mostly in the protocols that govern its underlying infrastructure. Traffic engineering in cloud data centers is one of these challenges that has attracted attention from the research community, particularly since the legacy protocols employed in data centers offer limited and unscalable traffic management. Many advocated for the use of VLANs as a way to provide scalable traffic management, however, finding the optimal traffic split between VLANs is the well known NP-Complete VLAN assignment problem. The size of the search space of the VLAN assignment problem is huge, even for small size networks. This paper introduce a novel decomposition approach to solve the VLAN mapping problem in cloud data centers through column generation. Column generation is an effective technique that is proven to reach optimality by exploring only a small subset of the search space. We introduce both an exact and a semi-heuristic decomposition with the objective to achieve load balancing by minimizing the maximum link load in the network. Our numerical results have shown that our approach explores less than 1% of the available search space, with an optimality gap of at most 4%. We have also compared and assessed the performance of our decomposition model and state of the art protocols in traffic engineering. This comparative analysis proves that our model attains encouraging gain over its peers. 2014 IEEE.Scopu
Iraqis in Egypt. A Statistical Survey in 2008
Emigration from Iraq has been occurring since the 1970s. The Iran-Iraq War, Gulf War and the
subsequent international sanctions placed on the Iraqi regime have all produced waves of
emigration. After US occupation of Iraq, however, and particularly since 2005, the country has
witnessed unprecedented levels of out-migration. Since the US led war on Iraq in 2003, massive
numbers of Iraqis have been displaced from their homes causing the largest influx of refugees into
the region. The situation of Iraqi refugees in Syria, Jordan and Lebanon has received the attention
of academics. In comparison, the picture of Iraqis in Egypt has remained obscure. This report
sheds light on the situation of Iraqis living in Egypt. It answers questions related to numbers of
Iraqis, reasons for choosing Egypt, patterns of flight, and the current situation and social networks
of this population