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1.
Chang Park Kapil Sugand Dinesh Nathwani Rajarshi Bhattacharya Khaled M Sarraf 《Acta orthopaedica》2020,91(5):556
Background and purpose — The COVID-19 pandemic has been recognized as an unprecedented global health crisis. This is the first observational study to evaluate its impact on the orthopedic workload in a London level 1 trauma center (i.e., a major trauma center [MTC]) before (2019) and during (2020) the “golden month” post-COVID-19 lockdown.Patients and methods — We performed a longitudinal observational prevalence study of both acute orthopedic trauma referrals, operative and anesthetic casemix for the first “golden” month from March 17, 2020. We compared the data with the same period in 2019. Statistical analyses included median (median absolute deviation), risk and odds ratios, as well as Fisher’s exact test to calculate the statistical significance, set at p ≤ 0.05.Results — Acute trauma referrals in the post-COVID period were almost halved compared with 2019, with similar distribution between pediatric and adult patients, requiring a significant 19% more admissions (RR 1.3, OR 2.6, p = 0.003). Hip fractures and polytrauma cases accounted for an additional 11% of the modal number of injuries in 2020, but with 19% reduction in isolated limb injuries that were modal in 2019. Total operative cases fell by a third during the COVID-19 outbreak. There was a decrease of 14% (RR 0.85, OR 0.20, p = 0.006) in aerosol-generating anesthetic techniques used.Interpretation — The impact of the COVID-19 pandemic has led to a decline in the number of acute trauma referrals, admissions (but increased risk and odds ratio), operations, and aerosolizing anesthetic procedures since implementing social distancing and lockdown measures during the “golden month.”The global impact of COVID-19The novel coronavirus SARS-COV-2 (COVID-19) was first reported in December 2019 with the first patient hospitalized in the city of Wuhan, China (Wu et al. 2020). By mid-March 2020 the outbreak affected over 190 countries with over 450,000 cases and over 20,000 deaths, thus being declared a pandemic and a global public health emergency by the World Health Organization (2020). On January 24, 2020 Europe reported its first case followed by a case in the United Kingdom (UK) 5 days later (Spiteri et al. 2020). Such a pandemic is an unprecedented event, and governments have had to enact firm social distancing and lockdown measures in an attempt to mitigate further viral transmission (Anderson et al. 2020) in order to reduce morbidity and mortality.British response to the pandemicThe English government responded by implementing social distancing measures on the March 16, 2020 in an attempt to reduce the rate of transmission and therefore the demands on the National Health Service (UK Government 2020a). This was followed a week later by more stringent measures, commonly referred to as a societal “lockdown” (UK Government 2020b). As of March 23, 2020, all members of the public were required to stay at home except for limited purposes and this ruling received Royal Assent by March 26 within the rest of the UK. Furthermore, all public gatherings of more than 2 people and non-essential businesses were suspended. In response to the NHS emergency declaration (National Health Service England 2020), the Royal College of Surgeons (2020) and the British Orthopaedic Association (2020) both issued statements and guidelines for delivering emergency trauma and orthopedic care during the COVID-19 outbreak. The phenomenon of a reduction in trauma burden due to such social distancing measures has been described by Stinner et al. (2020), as well as the potential impact of COVID-19 on operative capacity and pathways. There has been little to explore on how COVID-19 affects the etiology of trauma referral workloads and the operative casemix.We evaluated the impact of the COVID-19 pandemic at a central London level 1 trauma center, also known as a Major Trauma Centre (MTC), evaluating the trends of acute orthopedic trauma referral caseload and operative casemix before (2019) and during (2020) the COVID-19 lockdown (i.e., the “golden” month period starting from March 17). 相似文献
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Pretest prediction and diagnosis of metastatic lesions to the pancreas by endoscopic ultrasound‐guided fine needle aspiration 下载免费PDF全文
4.
SK Raina 《Journal of postgraduate medicine》2015,61(3):213-Sep;61(3):213
5.
Orly Levitan Jorge Dinamarca Ehud Zelzion Desmond S. Lun L. Tiago Guerra Min Kyung Kim Joomi Kim Benjamin A. S. Van Mooy Debashish Bhattacharya Paul G. Falkowski 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(2):412-417
Diatoms are unicellular algae that accumulate significant amounts of triacylglycerols as storage lipids when their growth is limited by nutrients. Using biochemical, physiological, bioinformatics, and reverse genetic approaches, we analyzed how the flux of carbon into lipids is influenced by nitrogen stress in a model diatom, Phaeodactylum tricornutum. Our results reveal that the accumulation of lipids is a consequence of remodeling of intermediate metabolism, especially reactions in the tricarboxylic acid and the urea cycles. Specifically, approximately one-half of the cellular proteins are cannibalized; whereas the nitrogen is scavenged by the urea and glutamine synthetase/glutamine 2-oxoglutarate aminotransferase pathways and redirected to the de novo synthesis of nitrogen assimilation machinery, simultaneously, the photobiological flux of carbon and reductants is used to synthesize lipids. To further examine how nitrogen stress triggers the remodeling process, we knocked down the gene encoding for nitrate reductase, a key enzyme required for the assimilation of nitrate. The strain exhibits 40–50% of the mRNA copy numbers, protein content, and enzymatic activity of the wild type, concomitant with a 43% increase in cellular lipid content. We suggest a negative feedback sensor that couples photosynthetic carbon fixation to lipid biosynthesis and is regulated by the nitrogen assimilation pathway. This metabolic feedback enables diatoms to rapidly respond to fluctuations in environmental nitrogen availability.In plants, carbon and nitrogen are directed to specific tissues or structures in accordance with developmental programs. In contrast, unicellular algae flexibly direct carbon and nitrogen to various macromolecules associated with specific intracellular compartments to optimize growth under varying environmental conditions. The signals responsible for this optimization strategy are poorly understood. They clearly are not driven by a developmental program but rather, responses to environmental cues. For example, under optimal growth conditions, ∼40% of the photosynthetically fixed carbon in typical eukaryotic microalga is directed toward the synthesis of amino acids that ultimately are incorporated into proteins (1–3). Over 50 y ago, however, it was recognized that, when nitrogen limits growth, intermediate metabolism is altered, and many microalgae can accumulate storage lipids, mainly in the form of triacylglycerols (TAGs) (4–6). This phenomenon is especially pronounced in diatoms.Diatoms, a highly successful class of eukaryotic algae that rose to ecological prominence during the past 30 My (7), often form massive blooms under turbulent conditions when nutrient supplies are highly variable (8). The ability of these organisms to optimize their growth under such conditions requires coordination of intermediate metabolism of carbon and nitrogen (9, 10). To optimize their growth, the first priority of the cells is to assimilate nitrogen into proteins, which also requires reducing equivalents and carbon skeletons that are primarily supplied by the tricarboxylic acid (TCA) cycle. However, when nitrogen availability decreases, the sink for TCA cycle metabolites declines, and acetyl-CoA, the source of carbon for the cycle, can be shunted toward fatty acid (FA) biosynthesis. Therefore, under nitrogen stress, cellular protein content decreases, whereas storage lipids increase (11, 12). This phenomenon has led to the hypothesis that overexpression of genes involved in lipid biosynthesis may increase the flux of carbon toward lipids (13, 14). Although this phenomenon is well-known, the signals that trigger the process remain unresolved. Genetic manipulations of lipid production in the model diatom, Phaeodactylum tricornutum, are ambiguous. Although there is one report showing that an overexpression of a type II diacylglycerol acyltransferase (DGAT; ProtID 49462) involved in TAG biosynthesis increases the accumulation of natural lipids in P. tricornutum (15), there are several reports indicating that manipulating FA biosynthesis does not significantly affect rates of lipid production (13, 14, 16).Using biochemical, physiological, bioinformatic, and reverse genetic approaches, we examine here how a diatom remodels intermediate metabolism to rapidly respond to nitrogen stress and its resupply. Our results reveal how carbon is redirected toward lipid biosynthesis under nitrogen stress in P. tricornutum. 相似文献
6.
Renu Sharma Aditya N Aggarwal Shuchi Bhatt Sudhir Kumar SK Bhargava 《Indian Journal of Orthopaedics》2015,49(5):542-548
Background:
de Quervain''s tenosynovitis is an inflammation of abductor pollicis longus (APL) and extensor pollicis brevis (EPB) muscle tendon sheaths at the level of radial styloid process. Its conservative management includes nonsteroidal anti-inflammatory drugs, wrist and thumb immobilization, ultrasonic therapy (US Th.) and low level laser therapy (LLLT). Literature is scanty on comparative efficacy of US Th. and LLLT for its management. This prospective study evaluates outcome of US Th. versus LLLT in de Quervain''s disease.Materials and Methods:
Thirty patients clinically diagnosed de Quervains tenosynovitis were included in the study and randomly assigned to two groups. The average age was 36 years (range: 21-45 years). One group was given LLLT and the other US Th. for a total of 7 exposures on alternate days. The clinical criteria used were Finkelstein''s test, tenderness over radial styloid (Ritchie''s tenderness scale), grip strength, pain (visual analog scale [VAS]) and radiological criteria was ultrasonographic assessment of change in thickness of APL and EPB tendon sheath. They were measured before commencement and at the end of seven sessions of therapy, as per standard procedure.Results:
Significant improvement was seen within both groups in the following outcome measures assessed: Ritchie''s tenderness scale, grip strength and VAS. Finkelstein''s test was not significantly improved in either groups. Ultrasonographic measurement of tendon sheath diameters, the mediolateral (ML), and anteroposterior (AP) diameters was not found to be significantly different in the US Th. group and the laser therapy group after treatment. On comparing both the groups, no statistically significant difference was found. However, looking at the mean values, the grip strength and VAS showed better improvement in the US Th. group as compared to the laser therapy group. 相似文献7.
Nemandra Sandiford SK Muirhead-Allwood JA Skinner 《Indian Journal of Orthopaedics》2015,49(6):595-601
Background:
Hip resurfacing arthroplasty (HRA) is primarily indicated for young, active patients with disabling coxarthrosis who wish to remain active and return to sports after surgery. Relatively few prospective studies have assessed return to sporting activity and impact of gender and age on this.Materials and Methods:
Seventy-nine consecutive patients treated with HRA were included. Patients were reviewed clinically and radiologically. Function was assessed using the modified University of California Los Angeles (UCLA) activity score. The Oxford, Harris and WOMAC hip scores were calculated.Results:
Average age at the time of surgery was 54.9 years (range 34.5–73.6 years). Average preoperative and postoperative UCLA scores were 4 and 7.6 respectively. Patients were involved in 2 (0–4) sporting activities preoperatively and 2 (0–5) postoperatively. Preoperative and postoperative Oxford Hip Scores, Harris Hip Score and WOMAC scores were 40, 46 and 51 and 16, 94 and 3 respectively (P < 0.0001). Patients returned to sports at an average of 3 months postoperatively.Conclusion:
Patients were able to return to sports by 3 months and perform the same number of activities at preoperative intensity. Activity levels are maintained up to the medium term with few complications. 相似文献8.
Continuous noninvasive cardiac output in children: is this the next generation of operating room monitors? Initial experience in 402 pediatric patients 下载免费PDF全文
9.
Kevin F. Erickson Matthew Mell Wolfgang C. Winkelmayer Glenn M. Chertow Jay Bhattacharya 《Journal of the American Society of Nephrology : JASN》2015,26(8):1990-1997
Medicare reimbursement policy encourages frequent provider visits for patients with ESRD undergoing hemodialysis. We hypothesize that patients seen more frequently by their nephrologist or advanced practitioner within the first 90 days of hemodialysis are more likely to undergo surgery to create an arteriovenous (AV) fistula or place an AV graft. We selected 35,959 patients aged ≥67 years starting hemodialysis in the United States from a national registry. We used multivariable regression to evaluate the associations between mean visit frequency and AV fistula creation or graft placement in the first 90 days of hemodialysis. We conducted an instrumental variable analysis to test the sensitivity of our findings to potential bias from unobserved characteristics. One additional visit per month in the first 90 days of hemodialysis was associated with a 21% increase in the odds of AV fistula creation or graft placement during that period (95% confidence interval, 19% to 24%), corresponding to an average 4.5% increase in absolute probability. An instrumental variable analysis demonstrated similar findings. Excluding visits in months when patients were hospitalized, one additional visit per month was associated with a 10% increase in odds of vascular access surgery (95% confidence interval, 8% to 13%). In conclusion, patients seen more frequently by care providers in the first 90 days of hemodialysis undergo earlier AV fistula creation or graft placement. Payment policies that encourage more frequent visits to patients at key clinical time points may yield more favorable health outcomes than policies that operate irrespective of patients’ health status. 相似文献
10.