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181.
Randa K. Elmallah Morad Chughtai Anton Khlopas Manoshi Bhowmik-Stoker Kevin J. Bozic Steven M. Kurtz Michael A. Mont 《The Journal of arthroplasty》2017,32(2):351-354
Background
With the implementation of the Patient Protection and Affordable Care Act, cost-effectiveness analyses are becoming increasingly important for resource allocation, and particularly for the justification of costly procedures, such as total knee and total hip arthroplasties (TKAs and THAs). Therefore, using the Short Form-6D (SF-6D) utility values, the purpose of this study was to determine (1) the quality-adjusted life years (QALYs) gained and (2) and the cost-effectiveness of undergoing THA and TKA.Methods
A total of 844 patients (357 men, 487 women) who had a mean age of 65 years (range, 39 to 80 years) underwent primary TKA, and 224 patients who had a mean age of 69 years (range, 44 to 88 years) underwent primary THAs at 7 institutions. The SF-6D values were derived for each patient preoperatively and at 1-year follow-up. QALYs were estimated at 1 year, and lifetime QALYs gained were determined using predicted life-expectancy values, at a discounted rate of 3% per year of life expectancy, to reflect a diminishing gain with time. National-level costs were determined using the 2011 Nationwide Inpatient Sample, and incremental cost-effectiveness ratios (ICER) were deduced for both groups.Results
The preoperative SF-6D values for the THA and TKA cohorts were 0.614 (range, 0.37 to 1) and 0.62 (range, 0.3 to 0.93). Postoperatively, SF-6D values improved significantly at 1 year in both groups. One-year QALYs for TKA and THA were 0.768 and 0.799. Lifetime QALYs gained for the groups were 2.07 and 1.85 (1.39 and 1.34 if discounted at a rate of 3% per year). The estimated ICER for TKA vs baseline presurgery was $43,107 per QALY, and $39,453 per QALY for THA vs baseline presurgery.Conclusion
The ICER showed that THA and TKA are cost-effective, compared to the $50,000 USD/QALY threshold for cost-effectiveness, and justify resources allocated to these surgeries. The SF-6D can utilize existing functional outcome data, which makes these cost calculations considerably easier and more feasible for practicing orthopedists. 相似文献182.
Morad Chughtai Anton Khlopas Chukwuwieke U. Gwam Randa K. Elmallah Melbin Thomas James Nace Michael A. Mont 《The Journal of arthroplasty》2017,32(4):1335-1339
Background
The purpose of our study was to compare (1) muscle strength; (2) pain; (3) sensation; (4) various outcome measurement scales between post-total hip arthroplasty (THA) patients who had a sciatic nerve injury and did or did not receive decompression surgery for this condition; and (5) to compare these findings with current literature.Methods
Nineteen patients who had nerve injury after THA were reviewed. Patients were stratified into those who had a nerve decompression (n = 12), and those who had not (n = 7). Motor strength was evaluated using the Muscle Strength Testing Scale. Pain was evaluated by using the visual analogue scale. Systematic literature search was performed to compare the findings of this study with others currently published.Results
The decompression group had a significant improvement in motor strength and the visual analog scale scores as compared with nonoperative group. Patients in decompression group had a significant larger increase in the mean Harris hip score and University of California Los Angeles score. There was no significant difference in the increase of Short Form-36 physical and mental scores between the 2 groups. Literature review for nonoperative management yielded 5 studies (93 patients), with 33% improvement. There were 7 studies (81 patients) on nerve decompression surgery, with 75% improvement.Conclusion
This study demonstrates the benefits of nerve decompression surgery in patients who had sciatic nerve injury after THA, as evidenced by results of standardized outcome measurement scales. It is possible to achieve improvements in terms of strength, pain, and clinical outcomes. Comparative studies with larger cohorts are needed to fully assess the best candidates for this procedure. 相似文献183.
Pseudoepidemic due to a unique strain of Mycobacterium szulgai: genotypic, phenotypic, and epidemiological analysis 下载免费PDF全文
Zhang Q Kennon R Koza MA Hulten K Clarridge JE 《Journal of clinical microbiology》2002,40(4):1134-1139
In mid-1999, we noted multiple isolations at the Veterans Affairs Medical Center (VAMC) Houston Tex. of an unusual nonpigmented Mycobacterium species. Since, on the basis of 16S rRNA gene sequence analysis, the strains were identical to the Mycobacterium szulgai type strain and since M. szulgai has been reported only rarely as a commensal or environmental isolate, we were concerned about laboratory contamination, nosocomial spread, or even the possibility that this could be a novel organism associated with disease. Our investigation found that from 1999 to 2000, 37 strains of M. szulgai were isolated from patients at the VAMC (the base rate for the previous 10 years had been <1 isolation per year). We compared the phenotypic properties and genetic relatedness of these 37 strains (31 of which were nonpigmented) as well as eight stock strains and the M. szulgai type strain. All strains were similar in cellular fatty acid patterns, growth rates, and biochemical characteristics. However, we found three genogroups by gene sequence analysis. Genogroup I comprised the M. szulgai type strain, all the tested nonpigmented strains (27 of the 31 strains were tested), two pigmented strains isolated in 1999 and 2000, and five pigmented stock strains. Genogroup II comprised five pigmented strains: three were isolated from 1999 to 2000 and two were stock strains. The single strain (isolated in 1996) in genogroup III was pigmented and was the only strain associated with disease. Whereas the randomly amplified polymorphic DNA (RAPD) patterns of all nonpigmented strains were identical, indicating that they came from a common source (the pseudoepidemic strain), the RAPD patterns of the other strains were varied. In our investigation for a possible source, we found that there were no common reagents, specimen-processing or patient locations, or procedures linking the 31 pseudoepidemic strains. However, a nonpigmented M. szulgai strain with a gene sequence and RAPD pattern identical to those of the pseudoepidemic strain was recovered from a water storage tank serving the hospital. We concluded that the strains most likely originated from hospital water, which transiently inoculated our patients. Although no disease was associated with this cluster of isolates, the event was costly because identification was problematic and we could not easily discount the isolations, since most of the patients were immunocompromised and were candidates for opportunistic infection. 相似文献
184.
In the present study, we examined the effects of chronic exposure (1 and 2 weeks) to an extremely low-frequency magnetic field (ELFMF) of 2 G intensity on memory in rats using an object recognition task. Comparable groups of rats were exposed for 1, 2 or 4 weeks to ELFMF and the following day blood samples were collected from each rat for the measurement of corticosterone level. Our results demonstrate that exposure to ELFMF induces a significant increase in the level of corticosterone in blood plasma and is associated with impairment in discrimination between familiar and novel objects. 相似文献
185.
Wegdan Bani-Issa Hadia Radwan Roba Saqan Heba Hijazi Randa Fakhry Mohamad Alameddine Farah Naja Ali Ibrahim Naing Lin Yuwadi Thein Naing Manal Awad 《Journal of sleep research》2023,32(1):e13666
The COVID-19 pandemic had a major impact on people of all ages. Adolescents' exposure to online learning is linked to excessive screen time on digital devices, which leads to poor sleep quality. This study aimed to investigate the association between screen time on different electronic devices and sleep quality among adolescents in the United Arab Emirates. This study was based on a self-reported questionnaire, which was administered online to school-aged adolescents (aged 12–19 years). The multicomponent questionnaire collected information on sociodemographic characteristics, sleep quality using the Pittsburgh Sleep Quality Index (PSQI), and screen time (minutes) on TV, TV-connected devices, laptops, smartphones, and tablets on weekdays, weeknight, and weekends using the Screen Time Questionnaire (STQ). Univariate and multivariate analyses were used to identify factors correlated with poor sleep quality. A total of 1720 adolescents were recruited from private and public schools (mean age 14.6 ± 1.97 years). The mean PSQI score was 8.09 ± 3.37, and 74.3% of participants reported poor sleep (cutoff score >5). Mean scores were highest for the sleep latency (1.85 ± 0.97) and sleep disturbance (1.56 ± 0.62) domains. The highest STQ score was observed for smartphones, with a median screen time of 420 min on weekdays and 300 min on weekends. Screen time related to smartphones on weekends (p = 0.003) and increased screen time in bed (p < 0.001) were significantly associated with poor sleep. Our results confirmed the correlation between sleep and screen time in adolescents. The results may inform educational polices that target screen time and sleep among adolescents during and after the COVID-19 pandemic. 相似文献
186.
Michelle D. Karpman Ronald Eldridge Jack L. Follis Carol J. Etzel Sanjay Shete Randa A. El-Zein 《Respiratory investigation》2018,56(1):28-33
Background
The prevalence of chronic obstructive pulmonary disease (COPD) in smokers enrolled as “healthy” controls in studies is 10–50%. The COPD status of ideal smoker populations for lung cancer case-control studies should be checked via spirometry; however, this is often not feasible, because no medical indications exist for asymptomatic smokers to undergo spirometry prior to study enrollment. Therefore, there is an unmet need for robust, cost effective assays for identifying undiagnosed lung disease among asymptomatic smokers. Such assays would help excluding unhealthy smokers from lung cancer case-control studies.Methods
We used the cytokinesis-blocked micronucleus (CBMN) assay (a measure of genetic instability) to identify undiagnosed lung disease among asymptomatic smokers. We used a convenience population from an on-going lung cancer case-control study including smokers with lung cancer (n = 454), smoker controls (n = 797), and a self-reported COPD (n = 200) contingent within the smoker controls.Results
Significant differences for all CBMN endpoints were observed when comparing lung cancer to All controls (which included COPD) and Healthy controls (with no COPD). The risk ratio (RR) was increased in the COPD group vs. Healthy controls for nuclear buds (RR 1.28, 95% confidence interval 1.01–1.62), and marginally increased for micronuclei (RR 1.06, 0.98–1.89) and nucleoplasmic bridges (RR 1.07, 0.97–1.15).Conclusion
These findings highlight the importance of using truly healthy controls in studies geared toward assessment of lung cancer risk. Using genetic instability biomarkers would facilitate the identification of smokers susceptible to tobacco smoke carcinogens and therefore predisposed to either disease. 相似文献187.
Mohamed Naguib Abdel Karim El Bakry Mohammed H. B. Khoshim Amir B. Channa Mohamed El Gammal Kariman El Gammal Yasser S. Elhattab Munir Attia Randa Jaroudi Abdulaziz Saddique 《Journal canadien d'anesthésie》1996,43(3):226-231
Purpose
Postoperative nausea and vomiting (PONV) is a distressing adverse effect of general anaesthesia. The aim of the current study was to compare the antiemetic activity of different 5-hydroxytryptamine3 receptor antagonists with that of metoclopramide and placebo.Methods
In a prospective, randomized, double-blind study we have compared the antiemetic activity of the prophylactic administration of ondansetron 4 mg, tropisetron 5 mg and granisetron 3 mg with that of metoclopramide 10 mg and placebo in 132 patients undergoing laparoscopic cholecystectomy. All study drugs and placebo were given as a short iv infusion ten minutes before the induction of anaesthesia. Perioperative anaesthetic care was standardized in all patients. Nausea and vomiting were assessed by direct questioning of the patient at 1, 4, 9, 12, 18 and 24 hr after recovery from anaesthesia. If patients experienced nausea and/or vomiting, rescue antiemetic treatment (metoclopramide 10 mg iv) was administered.Results
For the 24-hr recovery period after surgery, the percentages of emesis-free patients were 65.5%, 52%, 48%, 29.2% and 27.6% in the ondansetron, granisetron, tropisetron, metoclopramide and placebo groups, respectively. Prophylactic antiemetic treatment with ondansetron resulted in a lower incidence (P = 0.02) of PONV than with metoclopramide or placebo. The times at which rescue antiemetic was first received were longer (P < 0.01) in ondansetron group than in the placebo and metoclopramide groups. There were no statistical differences between ondansetron, tropisetron and granisetron groups.Conclusions
Ondansetron, when given prophylactically resulted in a significantly lower incidence of PONV than metoclopramide and placebo. Metoclopramide was ineffective. 相似文献188.
Comparative immunohistochemical profile of hepatocellular carcinoma,cholangiocarcinoma, and metastatic adenocarcinoma 总被引:9,自引:0,他引:9
Distinguishing hepatocellular carcinoma (HCC) from cholangiocarcinoma (CC) and metastatic adenocarcinoma (MA) involving the liver can be problematic, often requiring the use of immunohistochemistry to facilitate diagnosis. Hep Par 1, a monoclonal antibody with expression confined primarily to benign and malignant hepatocytes, has recently become commercially available. We evaluated Hep Par 1 along with other immunohistochemical markers used to differentiate HCC, CC, and MA, including AE1/AE3, CAM 5.2, B72.3, monoclonal carcinoembryonic antigen (mCEA), polyclonal CEA (pCEA), alpha-fetoprotein (AFP), factor XIIIa, inhibin, CD10, villin, MOC-31, cytokeratin (CK) 7, CK 19, and CK 20, to determine the markers most useful in differentiating these entities. Forty-two cases of HCC, 9 cases of CC, and 56 cases of MA (24 colon, 15 pancreas, 8 ovary, 5 breast, and 4 stomach) were studied. Hep Par 1 was sensitive and specific for HCC, with 38 of 42 (90%) cases staining positively, whereas reactivity was observed in only 8 of 56 (14%) MAs and 0 of 9 CCs. Though limited somewhat by poor sensitivity, a bile canalicular pattern of staining with pCEA, CD10, and villin was specific for HCC and was not observed in the other tumors. Lack of mCEA and MOC-31 immunoreactivity was also characteristic of HCCs. CK 19 positivity favored CC over HCC, but was not useful in differentiating CC from MA. Expression of AFP, although observed in only about one third of the cases, favored HCC over CC and MA. CK 7 and CK 20 were also useful in this differential diagnosis, particularly when dealing with MA of colonic origin. AE1/AE3, CAM 5.2, B72.3, inhibin, and factor XIIIa were noncontributory in differentiating these entities. 相似文献
189.
Randa Alfotawi Mona Elsafadi Manikandan Muthurangan Abdul-Aziz Siyal Musaad Alfayez Amer A. Mahmmod 《Journal of investigative surgery》2021,34(1):44-54
AbstractBackground: Osteoporosis is associated with a metabolic imbalance between adipogenesis and osteogenesis. We hypothesized that implanting a carrier for differentiated stem cells and signaling molecules inside adipose tissues could be used to enable transdifferentiation between cells, upregulate osteogenesis, and support bone formation, which may regain the balance between osteogenesis and adipogenesis. Methodology: A CL1 human mesenchymal stem cell line was grown in an osteogenic medium to differentiate into osteoblasts, and the differentiated cells were then exposed to an adipogenic medium to stimulate differentiation into adipocytes. Osteogenic and adipogenic differentiation were confirmed by the following assays: alkaline phosphatase staining, Nile red Staining, and quantitative real-time polymerase chain reaction (qPCR). The ratio of adipocytes to osteocytes for both cases was calculated. To evaluate bone induction in vivo, a calcium sulfate/hydroxyapatite cement was prepared in a syringe and then seeded with 106 cells/mL of rat bone marrow stromal cells (rMSCs) and covered with 1?mL of tissue culture media containing 0.1?mg of bone morphogenetic protein 7 (BMP-7). The construct was injected into the abdominal fat tissue of 10 male Sprague-Dawley rats. Results: The conversion of osteocytes to adipocytes was 20-fold greater than the reverse conversion, and the area of bone regeneration was 15.7?±?3.7%, the area of adipose tissue was 65.8?±?13.1%, and the area of fibrous tissue was 18.3?±?7.8%. Conclusion: Adipogenic interconversion and associated bone formation demonstrate the potential of a new therapy for balancing osteogenesis and adipogenesis. 相似文献
190.
Todd P. Pierce Julio J. Jauregui Randa K. Elmallah Carlos J. Lavernia Michael A. Mont James Nace 《Current reviews in musculoskeletal medicine》2015,8(3):228-232
The review describes the following: (1) how traditional core decompression is performed, (2) adjunctive treatments, (3) multiple percutaneous drilling technique, and (4) the overall outcomes of these procedures. Core decompression has optimal outcomes when used in the earliest, precollapse disease stages. More recent studies have reported excellent outcomes with percutaneous drilling. Furthermore, adjunct treatment methods combining core decompression with growth factors, bone morphogenic proteins, stem cells, and bone grafting have demonstrated positive results; however, larger randomized trial is needed to evaluate their overall efficacy. 相似文献