660 research outputs found
Prevention of infection and disruption of the pathogen transfer chain in elective surgery
The COVID-19 pandemic has caused us all to stop our normal activities and consider how we can safely return to caring for our patients. There are many common practices (such as an increased use of personal protective equipment) which we are all familiar with that can be easily incorporated into our daily routines. Other actions, such as cleaning more surfaces with solutions such as dilute povidone iodine or changing the air filtration systems used within operating room theaters, may require more extensive efforts on our behalf. In this article, we have attempted to highlight some of the changes that arthroplasty surgeons may need to instigate when we are able to resume elective joint arthroplasty procedures in an effort to disrupt the chain of pathogen transfer
Bilateral adrenal hemorrhage in a total knee patient associated with enoxaparin usage
AbstractBilateral adrenal hemorrhage is a rare but potentially catastrophic complication of chemoprophylaxis. We report a patient who underwent a total knee arthroplasty and subsequently developed bilateral adrenal hemorrhage from enoxaparin. Once the patient was diagnosed with acute adrenal insufficiency, corticosteroids were promptly started, and the patient made a dramatic recovery and did not suffer further complications
Lower Body Joint Moments during the Golf Swing in Older Adults: Comparison to Other Activities of Daily Living
Golf participation has increased dramatically in the last several years. With this increase in participation, clinicians need better evidenced based strategies to advise those golfers with different pathologies when it is safe to return to the game. Golf teaching professionals also need to understand how to alter golf mechanics to protect injured and/or diseased joints in golfers to allow them to play pain free and avoid further injury. This study used a 3-dimensional link segment model to calculate the net joint moments on the large lower limb joints (knee and hip) during golf (lead and trail leg) and two commonly studied activities of daily living (gait and sit-to-stand) in 22 males, healthy, adult golfers. It also examined the correlations between these knee and hip joint loads and club head speed. The external valgus knee moment and the internal hip adduction moment were greater in the lead leg in golf than in the other activities and were also correlated with club head speed. This indicates a strategy of using the frontal plane GRF moment during the swing. The internal hip extension and knee flexion moment were also greater in the golf swing as compared with the other activities and the hip extension moment was also correlated with club head speed. This emphasizes the importance of hip extensor (i.e., gluteus maximus and hamstring) muscle function in golfers, especially in those emphasizing the use of anterior-posterior ground reaction forces (i.e., the pivoting moment). The golf swing places some loads on the knee and the hip that are much different than the loads during gait and sit-to-stand tasks. Knowledge of these golf swing loads can help both the clinician and golf professional provide better evidence-based advice to golfers in order to keep them healthy and avoid future pain/injury
DOES HAND SPEED RELATE TO CLUB HEAD SPEED OR BALL SPEED DURING A GOLF SWING?
Many golf swing analyses use club or ball speed to indicate performance, although these are difficult to obtain using motion capture. This study examined the relationship between hand speed and club head and ball speeds to examine if hand can indicate performance and if different capturing frequencies affect these relationships. A 10-camera Vicon system recorded golfers performing eight golf swings (500 Hz n=11, 100 Hz n=15). A TrackMan system recorded club head and ball speed. The resultant hand speed was calculated at peak velocity, the lowest position of the hands, and at ball impact. Hand speed at ball impact and club head speed had the strongest relationship (r=0.501, p\u3c0.001), though most correlations were r\u3c0.400. Higher capturing frequency had better relationships with the performance outcomes, and the ball impact was the best time point for analysis
Clinical Utility of Mesenchymal Stem/stromal Cells in Regenerative Medicine and Cellular Therapy
Mesenchymal stem/stromal cells (MSCs) have been carefully examined to have tremendous potential in regenerative medicine. With their immunomodulatory and regenerative properties, MSCs have numerous applications within the clinical sector. MSCs have the properties of multilineage differentiation, paracrine signaling, and can be isolated from various tissues, which makes them a key candidate for applications in numerous organ systems. To accentuate the importance of MSC therapy for a range of clinical indications, this review highlights MSC-specific studies on the musculoskeletal, nervous, cardiovascular, and immune systems where most trials are reported. Furthermore, an updated list of the different types of MSCs used in clinical trials, as well as the key characteristics of each type of MSCs are included. Many of the studies mentioned revolve around the properties of MSC, such as exosome usage and MSC co-cultures with other cell types. It is worth noting that MSC clinical usage is not limited to these four systems, and MSCs continue to be tested to repair, regenerate, or modulate other diseased or injured organ systems. This review provides an updated compilation of MSCs in clinical trials that paves the way for improvement in the field of MSC therapy
Generalized h-index for Disclosing Latent Facts in Citation Networks
What is the value of a scientist and its impact upon the scientific thinking?
How can we measure the prestige of a journal or of a conference? The evaluation
of the scientific work of a scientist and the estimation of the quality of a
journal or conference has long attracted significant interest, due to the
benefits from obtaining an unbiased and fair criterion. Although it appears to
be simple, defining a quality metric is not an easy task. To overcome the
disadvantages of the present metrics used for ranking scientists and journals,
J.E. Hirsch proposed a pioneering metric, the now famous h-index. In this
article, we demonstrate several inefficiencies of this index and develop a pair
of generalizations and effective variants of it to deal with scientist ranking
and with publication forum ranking. The new citation indices are able to
disclose trendsetters in scientific research, as well as researchers that
constantly shape their field with their influential work, no matter how old
they are. We exhibit the effectiveness and the benefits of the new indices to
unfold the full potential of the h-index, with extensive experimental results
obtained from DBLP, a widely known on-line digital library.Comment: 19 pages, 17 tables, 27 figure
Causas de Morte em Doentes com Hemofilia: Estudo Retrospectivo de 1979 a 2007, no Serviço de Imunohemoterapia do HSJ
Neurokinin A (NKA) induces bronchoconstriction mediated by tachykinin NK2 receptors in animals and humans, and may be increased in asthma. Because beta(2)-adrenoceptor agonists are the most widely used bronchodilators in asthma, we investigated the effects of the beta(2)-adrenoceptor agonist fenoterol on NK2 receptor messenger RNA (mRNA) and receptor density as well as the functional responses of bovine tracheal smooth muscle to the NK2 receptor agonist [beta-Ala(8)]-NKA(4-10) in vitro, using Northern blot analysis, receptor binding, and organ bath studies. Incubation with fenoterol induced a time- and concentration-dependent upregulation of NK2 receptor mRNA (71% increase after 12 h at 10(-7) M fenoterol), which was abolished by propranolol (a nonselective beta-adrenoceptor agonist) and ICI118551 (a selective beta(2)-adrenoceptor antagonist), but not by CGP20712A (a selective beta(1)-adrenoceptor antagonist), indicating that fenoterol acts via beta(2)-adrenoceptors. These effects were mimicked by forskolin and prostaglandin E-2 (PGE,), both agents that increase cyclic adenosine monophosphate (cAMP), and by the cAMP analogue 8-bromo-cAMP. The upregulation was blocked by cycloheximide, indicating that it requires new protein synthesis, and was accompanied by an increase in both the stability of NK2 receptor mRNA and the rate of NK2 receptor gene transcription. Radioligand binding assay using the selective NK2 receptor antagonist [H-3]SR48968 showed a significant increase in the number of receptor binding sites after 12 h and 18 h, which was accompanied by an increased contractile responsiveness to the NK2 receptor agonist [beta-Ala(8)]-NKA(4-10). Dexamethasone completely prevented the fenoterol-induced increase in NK2 receptor mRNA and in the contractile response. We conclude that beta(2)-adrenoceptor agonists induce upregulation of functional NK2 receptors in airway smooth muscle by increasing cAMP, and that this can be prevented by a corticosteroid. The increased responsiveness could be relevant to asthma control and mortality
A NOTCH3-CXCL12-driven myeloma-tumor niche signaling axis promotes chemoresistance in multiple myeloma
Multiple myeloma (MM) remains incurable due to disease relapse and drug resistance. Notch signals from the tumor microenvironment (TME) confer chemoresistance, but the cellular and molecular mechanisms are not entirely understood. Using clinical and transcriptomic datasets, we found that NOTCH3 is upregulated in CD138+ cells from newly diagnosed MM (NDMM) patients compared to healthy individuals and increased in progression/relapsed MM (PRMM) patients. Further, NDMM patients with high NOTCH3 expression exhibited worse responses to Bortezomib (BOR)-based therapies. Cells of the TME, including osteocytes, upregulated NOTCH3 in MM cells and protected them from apoptosis induced by BOR. NOTCH3 activation (NOTCH3OE) in MM cells decreased BOR anti-MM efficacy and its ability to improve survival in in vivo myeloma models. Molecular analyses revealed that NDMM and PRMM patients with high NOTCH3 exhibit CXCL12 upregulation. TME cells upregulated CXCL12 and activated the CXCR4 pathway in MM cells in a NOTCH3-dependent manner. Moreover, genetic or pharmacologic inhibition of CXCL12 in NOTCH3OE MM cells restored sensitivity to BOR regimes in vitro and in human bones bearing NOTCH3OE MM tumors cultured ex vivo. Our clinical and preclinical data unravel a novel NOTCH3-CXCL12 pro-survival signaling axis in the TME and suggest that osteocytes transmit chemoresistance signals to MM cells
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