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61.
Methods
Nineteen cases of extension contracture were operated upon by modified technique of Judet quadricepsplasty, one female and eighteen males. Results were evaluated by HSSKF score as well as Judet criteria.Purpose
The hypothesis is that recurrence of adhesions underneath the quadriceps leads to loss of some of the gained intraoperative flexion range.Results
In this series, flexion range deteriorates but this was found to be statistically non significant on the functional score of the patients. 相似文献62.
Yasser Emad Ashraf Anbar Ihab Abo-Elyoun Nashwa El-Shaarawy Hadeel Al-Hanafi Hatem Darwish Mona Gamil Johannes J. Rasker 《Clinical rheumatology》2014,33(6):791-797
This study aimed to determine the frequency of rheumatoid factor (RF) and cyclic citrullinated peptide (CCP) antibodies in a cohort of patients with palindromic rheumatism (PR) and to find determinants for progression to rheumatoid arthritis (RA). All new cases of PR (n?=?90) were included prospectively and followed up for 1 year, and a comparison group of RA cases (n?=?70) was also included. At study entry in all patients in both groups, RF and anti-CCP antibodies were tested, and the findings were compared and correlated. In the PR group at presentation, RF was positive in 30 patients (33.3 %) and, in the RA group, in 45 patients (64.3 %). Anti-CCP antibodies were positive in 35 patients (38.9 %) with PR and in 58 patients (82.9 %) with RA. In the PR group, positive correlations were observed between RF and C-reactive protein (CRP) (p?=?0.036), while anti-CCP positively correlated with disease duration (p?=?0.015) and CRP (p?<?0.001). At 1-year follow-up, 25 cases (27.5 %) had progressed to RA, 3 (3.3 %) cases had developed systemic lupus, 43 cases had responded to hydroxychloroquine with complete remission, five cases had developed other rheumatic diseases, and 14 cases had progressed to undifferentiated arthritis. After regression analysis, the involvement of hand joints and positive anti-CCP were the only predictors that determined progression into RA within a year (p?<?0.001 and p?=?0.02, respectively). Early hand joint involvement and positive anti-CCP at disease onset are good predictors for progression to RA in this domain. 相似文献
63.
Ahmed Ezzat Siam Hesham El Saghir Tarek El-Fiky Osama Moustafa Yasser El Mansy 《European orthopaedics and traumatology》2014,5(2):131-137
Background
The purpose of this study was to assess prospectively operative results and complications of treatment of cervical spinal canal stenosis (CCS) by anterior cervical discectomy and fusion (ACDF) using a newly introduced Alexandria Modular Cage-Plate Construct (AMCPC).Methods
Fifteen patients (eight males, seven females) with symptomatic CCS were treated by ACDF, with a mean age of 51.2 years. Post-operative assessment depended upon clinical and radiological results.Results
Total number of operated levels was 25 levels, with a mean 1.67 levels/patient. Mean operative time was 69.6 min/level and 116 min/patient. Average blood loss was 78 mL/level and 130 mL/patient. Mean hospital stay was 2.8 days. Post-operative dysphagia/dysphonia persisted in one patient for 1 year. One patient developed C5 radiculopathy with grade 2 deltoid weakness that recovered after 3 months. According to Odom’s criteria, results were excellent in 13 patients (86.67 %), good in 1 (6.67 %), and fair in 1 patient. In 13 patients (23 cage-plates, 92 %), the implant showed to be completely contained until the end of follow-up (24 months). One patient had a broken screw and one had screw backing-out, both did not necessitate revision. The achieved sagittal profile was maintained without sinking-in of any cage.Conclusion
AMCPC can be used safely for a variety of disorders requiring instrumentation and fusion. It is advantageous to stand-alone cage and to rigid cage-plates when intraoperative flexibility is needed. It overcomes the disadvantages of stand-alone cage, sinking-in, cage dislodgement and post-operative rekyphosis. In addition, it obviates the need for wearing post-operative neck collar. 相似文献64.
Yasser A. Radwan Ali M. Reda Mansour Ahmed Rizk George Malak 《European orthopaedics and traumatology》2014,5(3):253-260
Introduction
The purpose of this study was to assess the effect of osteoarthritis on the outcome of arthroscopic anterior cruciate ligament (ACL) reconstruction, and to assess the effect of the procedure on the progression of osteoarthritis.Material and methods
Forty-two patients, age above 40, presenting by symptomatic instability secondary to rupture of the ACL were enrolled in a prospective cohort study. Cases were divided into two groups according to the absence of osteoarthritic changes (group I, 19 patients) or presence of osteoarthritic changes (group II, 23 patients) in preoperative radiographs. ACL anatomic single bundle reconstruction by the anteromedial portal technique using hamstring autograft fixed by biodegradable interference fit screws was done for all patients, and a fixed postoperative rehabilitation protocol was applied. Data were recorded and statistical analysis of the preoperative, 1 year follow up, and final follow up (average 41 months in group I and 42 months in group II) results of both groups was conducted.Results
The average patient age at the time of operation was 44.5 years in group I versus 46.4 years in group II. The follow-up median pain scores, ROM, modified Lysholm scores were significantly better in group I compared to group II. On the contrary, the difference between preoperative and 1 year postoperative scores and the percentage of improvement of the modified Lysholm score were significantly higher in group II. Deterioration of the radiographic grade of osteoarthritis in the final follow-up was declared in 15.8 % of patients of group I and in 21.7 % of patients of group II (P?=?0.71). Age, concomitant meniscus injury, and presence of preoperative arthritic changes, and cartilage defect had no statistically significantly effect on the success rate. Patients who had ACL reconstruction more than 2 years after injury and those with higher body mass index (BMI) had worse outcome than those who had earlier reconstruction and lower BMI.Conclusion
Patients having preoperative mild to moderate arthritic changes will indeed benefit from ACL reconstruction at short term, although their overall functional outcome seemed to be inferior to the outcome of non-arthritic patients. However, osteoarthritic changes deteriorate over time in both groups especially when there is preoperative mild to moderate arthritic changes. 相似文献65.
Jannel Acosta Yamila Carpio Iris Valdés Janet Velázquez Yasser Zamora Reynold Morales Antonio Morales Elsa Rodríguez Mario P. Estrada 《Vaccine》2014
Modern vaccines based on purified recombinant antigens have improved their safety; however they induce a suboptimal immune response without the help of adjuvants. Consequently, the development of new adjuvants to enhance the immunogenicity of purified subunit antigens and modulate resulting immune responses is of great interest. In the present study, we evaluated the ability of antimicrobial peptides Oreochromicins previously isolated from tilapia Oreochromis niloticus to enhance adaptive immune responses in mice and tilapia. When co-administrated with ovalbumin in mice, Oreochromicin-1 induced a TH1 humoral immune response. Oreochromicin-2 and 3 induce a TH1 cellular immune response characterized by the induction of interferon-γ in a dose depend manner. Additionally, co-administration of Oreochromicin-1 with the sea lice my32 from Lepeophtheirus salmonis antigen (my32-Ls) increases the humoral immune response in mice and tilapia. We also tested different combinations of these Oreochromicins with the sea lice antigen my32-Ls in mice. Humoral and cellular TH1 responses were enhanced by co-administration of my32-Ls/Oreochromicin-3 and the combination my32-Ls/Oreochromicin-2/3. In agreement with these results, Oreochromicin-1 and 3 enhanced in vitro TH1 cytokine IFN-γ production in Concanavalin A primed splenocytes from naïve mice after a 48 h incubation period. In summary, the results showed that tilapia alpha-helical antimicrobial peptides Oreochromicins are able to boost immune response in mammals and fish, encouraging their use as TH1 molecular adjuvants to subunit antigens. 相似文献
66.
Yasser Khafagy Mohamed Ghonim Saad Elzayat Ahmed Elgendy 《American journal of otolaryngology》2021,42(5):102998
BackgroundFrontal sinusotomy is a challenging procedure that needs meticulous handling due to its unique anatomical position. Postoperative middle turbinate lateralization is critical comorbidity for the success rate, and many techniques are adopted to prevent it. The study aimed to compare the effect of middle turbinate bolgerization and partial resection on the postoperative endoscopic scores and assess their impact on the middle meatus and the frontal recess outcome.Patient and methodsThis prospective study was conducted on forty-one patients undergoing bilateral frontal sinusotomy for chronic frontal sinusitis. Nasal cavities were randomized so that partial middle turbinate resection technique was done alternately with bolgerization approach in every patient. Each participant acted as their control. Both sides were compared using Lund Kennedy Endoscopic Score (LKES) and Perioperative Sinus Endoscopy Score (POSE) at the baseline, 1st, 3rd, and 12th-month intervals postoperatively. Also, middle turbinate status was assessed at the end of the 12th-month interval using POSE score.ResultsThe total frontal sinus patency rate was 82.9% (63/76 operated sinus). Baseline scores, LKES (3.79 ± 0.777 vs 4.05 ± 0.769, p = 0.142, for the side of resection and the side for bolgerization respectively) and POSE (1.79 ± 0.413 vs 1.82 ± 0.393, p = 0.777, for the side of resection and the side for bolgerization respectively). Regarding LKES, the differences between both operated sides were fluctuating with p values: 0.001*, 0.171, and 0.044* for the 1st, 3rd, and 12th months follow-up intervals, respectively. Regarding the POSE score of the frontal sinus, the difference between both groups was steadily increasing with p values: 0.318, 0.119, and 0.017* for the 1st, 3rd, and 12th months follow-up intervals. The middle turbinate's POSE score at the 12th month was significantly higher in the side allocated for bolgerization (p-value = 0.008*).ConclusionPartial middle turbinate resection showed favorable endoscopic outcomes than bolgerization at the 12th month follow up period in patients undergoing primary ESS for chronic frontal sinusitis. 相似文献
67.
María Lacalle-Aurioles José M Mateos-Pérez Juan A Guzmán-De-Villoria Javier Olazarán Isabel Cruz-Ordu?a Yasser Alemán-Gómez María-Elena Martino Manuel Desco 《Journal of cerebral blood flow and metabolism》2014,34(4):654-659
The purpose of this study was to elucidate whether cerebral blood flow (CBF) can better characterize perfusion abnormalities in predementia stages of Alzheimer''s disease (AD) than cerebral blood volume (CBV) and whether cortical atrophy is more associated with decreased CBV or with decreased CBF. We compared measurements of CBV, CBF, and mean cortical thickness obtained from magnetic resonance images in a group of healthy controls, patients with mild cognitive impairment (MCI) who converted to AD after 2 years of clinical follow-up (MCI-c), and patients with mild AD. A significant decrease in perfusion was detected in the parietal lobes of the MCI-c patients with CBF parametric maps but not with CBV maps. In the MCI-c group, a negative correlation between CBF values and cortical thickness in the right parahippocampal gyrus suggests an increase in CBF that depends on cortical atrophy in predementia stages of AD. Our study also suggests that CBF deficits appear before CBV deficits in the progression of AD, as CBV abnormalities were only detected at the AD stage, whereas CBF changes were already detected in the MCI stage. These results confirm the hypothesis that CBF is a more sensitive parameter than CBV for perfusion abnormalities in MCI-c patients. 相似文献
68.
69.
Yasser Khazaal Mathias van Singer Anne Chatton Sophia Achab Daniele Zullino Stephane Rothen Riaz Khan Joel Billieux Gabriel Thorens 《Journal of medical Internet research》2014,16(7)
Background
The number of medical studies performed through online surveys has increased dramatically in recent years. Despite their numerous advantages (eg, sample size, facilitated access to individuals presenting stigmatizing issues), selection bias may exist in online surveys. However, evidence on the representativeness of self-selected samples in online studies is patchy.Objective
Our objective was to explore the representativeness of a self-selected sample of online gamers using online players’ virtual characters (avatars).Methods
All avatars belonged to individuals playing World of Warcraft (WoW), currently the most widely used online game. Avatars’ characteristics were defined using various games’ scores, reported on the WoW’s official website, and two self-selected samples from previous studies were compared with a randomly selected sample of avatars.Results
We used scores linked to 1240 avatars (762 from the self-selected samples and 478 from the random sample). The two self-selected samples of avatars had higher scores on most of the assessed variables (except for guild membership and exploration). Furthermore, some guilds were overrepresented in the self-selected samples.Conclusions
Our results suggest that more proficient players or players more involved in the game may be more likely to participate in online surveys. Caution is needed in the interpretation of studies based on online surveys that used a self-selection recruitment procedure. Epidemiological evidence on the reduced representativeness of sample of online surveys is warranted. 相似文献70.
Benjamin J. Koestler Sergey S. Seregin David P. W. Rastall Yasser A. Aldhamen Sarah Godbehere Andrea Amalfitano Christopher M. Waters 《Clinical and Vaccine Immunology : CVI》2014,21(11):1550-1559
The bacterial second messenger cyclic di-GMP (c-di-GMP) stimulates inflammation by initiating innate immune cell recruitment and triggering the release of proinflammatory cytokines and chemokines. These properties make c-di-GMP a promising candidate for use as a vaccine adjuvant, and numerous studies have demonstrated that administration of purified c-di-GMP with different antigens increases protection against infection in animal models. Here, we have developed a novel approach to produce c-di-GMP inside host cells as an adjuvant to exploit a host-pathogen interaction and initiate an innate immune response. We have demonstrated that c-di-GMP can be synthesized in vivo by transducing a diguanylate cyclase (DGC) gene into mammalian cells using an adenovirus serotype 5 (Ad5) vector. Expression of DGC led to the production of c-di-GMP in vitro and in vivo, and this was able to alter proinflammatory gene expression in murine tissues and increase the secretion of numerous cytokines and chemokines when administered to animals. Furthermore, coexpression of DGC modestly increased T-cell responses to a Clostridium difficile antigen expressed from an adenovirus vaccine, although no significant differences in antibody titers were observed. This adenovirus c-di-GMP delivery system offers a novel method to administer c-di-GMP as an adjuvant to stimulate innate immunity during vaccination. 相似文献