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101.
Gag-CD8+ T cell responses are associated with immune control of HIV infection. Since during HIV infection Nef impairs T cell responses, we evaluated whether deletion of nef from a non-infectious HIV DNA vaccine (Delta4 Nef+), creating Delta5 Nef(-), would affect its immunogenicity. When compared with Delta4, mice injected with Delta5 developed significantly lower CD8+ T cell responses to Gag, but no significant change in the responses to Env was observed. In vitro, deletion of Nef abrogated the induced cell death, production of virus-like particles and release of Gag from transfected cells. Thus, the effect of Nef in causing extrusion of Gag might adjuvant the CD8+ T cell responses to Gag in DNA vaccine. 相似文献
102.
Sonia Attia Sana Khochtali Rim Kahloun Dhiaeddine Ammous Bechir Jelliti Salim Ben Yahia Sonia Zaouali Moncef Khairallah 《International ophthalmology》2016,36(1):37-44
The purpose of this study was to describe the clinical and multimodal imaging findings in acute Vogt–Koyanagi–Harada (VKH) disease without clinically evident exudative retinal detachment (ERD). We retrospectively reviewed the charts of 18 patients (36 eyes), diagnosed with acute VKH disease without clinically evident ERD. All patients underwent complete ophthalmic examination, fundus photography, optical coherence tomography (OCT), B-scan ultrasonography, fluorescein angiography (FA), and indocyanine green angiography (ICGA). Of 18 patients, twelve (66.7 %) were female and 6 (33.3 %) were male. Mean age was 39 years (range, 23–60). Ten patients had been referred with an erroneous diagnosis of primary optic nerve disorder (8; 44.4 %) or isolated anterior uveitis (2; 11.1 %). Anterior chamber or vitreous inflammatory reaction was noted in 22 eyes (61.1 %), each. Fundus findings included optic disc swelling in 30 eyes (83.3 %), retinal striae in 20 eyes (55.5 %), and yellowish deep lesions in 3 eyes (8.3 %). OCT showed a shallow, localized subclinical ERD in 18 eyes (50 %), and retinal pigment epithelial folds in 23 eyes (63.9 %). B-scan ultrasonography showed diffuse, low- to medium-reflective choroidal thickening in all eyes. FA disclosed delayed choroidal perfusion in at least one eye of all patients (100 %), mild pinpoint leakage in 21 eyes (58.3 %), optic disc hyperfluorescence in 35 eyes (97.2 %) and choroidal folds in 13 eyes (36.1 %). ICGA findings included delayed choroidal perfusion in 24 eyes (66.7 %), decrease in the number of large choroidal vessels in 36 eyes (100 %), fuzzy choroidal vessels in 35 eyes (97.2 %), and hypofluorescent dark dots in 28 eyes (77.8 %). The association of bilateral optic disc edema with retinal striae and intraocular inflammatory reaction highly suggests acute VKH disease. A multimodal imaging approach including fundus photography, OCT, B-scan ultrasonography, FA, and ICGA provides important clues for the definite diagnosis and help differentiate VKH disease from primary optic nerve disorders. 相似文献
103.
Youssriah Yahia Sabri Khaled Mahmoud Kamel Mona Ahmed Fouad Hafez Sara Mohamed Saleh Saleh Nasef 《The Egyptian Journal of Radiology and Nuclear Medicine》2017,48(4):947-952
Objective
This work aimed for using multislice computed tomography (MSCT) to map the bronchial tree and assess the exact site, direction, airway findings and bronchial measurements to guide trans-bronchial lung biopsy from an inaccessible lung lesion.Patients and methods
This study was carried on 26 patients. It was conducted in the Radiology Department, in collaboration with Chest Department, in the period from January 2015 to April 2016. All patients were subjected to Virtual Bronchographic (VB) examination and Trans-Bronchial lung biopsy (in selected cases guided by the VB results).Results
In this study, MSCT-VB maps guided the fiber-optic bronchoscopy in 30 bronchial lesions in 26 patients to the proper sampling site for different lung lesions with success rate 100% and CT maps were done, reaching 3rd to 7th order bronchial generation with mean distance from central bronchi was 21.3?mm and mean target bronchial diameter was 1.9?mm. Right sided lesions encountered in 57.7% and left sided lesions in 42.3% with the most common segmental affection was the right upper lobe in 36.7% of bronchial lesions and the apico-posterior subsegment of left upper lobe in 23.3% of lesions, then planning according to the site of the lesion in relation to the bronchial tree in the VB was done. Histopathological assessment was done with 61.5% neoplastic lesions and 38.5% inflammatory lesions.Conclusion
Multiplanar reconstruction images together with virtual bronchographic images were accurate in the detection of lesion’s site, depiction of degree of narrowing, and distal visualization of airways. This CT map should be used to guide bronchoscopy or to direct trans-bronchial needle biopsy to guarantee positive histopathological results. 相似文献104.
There is a need for better understanding of the biocompatibility of alginate-polycation microcapsules based on their physicochemical characteristics. Microcapsules composed of alginate with 44% (IntG) or 71% (HiG) guluronate, gelled with calcium (Ca) or barium (Ba) and coated with poly-L-lysine (PLL) or poly-l-ornithine (PLO), followed by IntG alginate were compared. For microcapsules with an IntG(Ca) gel core, using PLO instead of PLL resulted in less immune cell adhesion after 2 days in C57BL/6J mice. The PLO microcapsules were also characterized by greater hydrophilicity and superior resistance to swelling and damage under osmotic stress. For microcapsules with a PLL membrane, replacing the IntG(Ca) gel core with IntG(Ba) or HiG(Ca) gel resulted in stronger immune responses (p<0.05). This was explained by poor penetration of PLL into the gel, as demonstrated by Fourier transform infrared spectroscopy analyses and membrane rupturing during osmotic swelling. X-ray photoelectron spectroscopy analyses show that all microcapsules had the same amount of polycation at their surface. Moreover, alginate coatings had non-significant effects on the biocompatibility and physicochemical properties of the microcapsules. Thus, alginate-polycation interactions for membrane formation are more important for biocompatibility than either the quantity of polycation at the surface or the alginate coating. 相似文献
105.
Magdy E. Saafan Sameh M. Ragab Osama A. Albirmawy Hosam S. Elsherif 《European archives of oto-rhino-laryngology》2013,270(1):149-155
To conduct a prospective randomized controlled trial investigating the efficacy and safety of powered versus conventional endoscopic sinus surgery instruments in the management of sinonasal polyposis. Two hundred patients with sinonasal polyposis who failed conservative therapy were included in the study. They were equally randomized into powered and conventional instruments groups. A subjective visual analogue scale (VAS), endoscopic examination, saccharine clearance time and coronal CT were done preoperatively. Intraoperatively, the operative time, the surgical conditions and degrees of dryness of the operative field were carefully rated and recorded. Postoperatively, VAS, polyp grades, saccharine clearance time, the number of endoscopic debridement and time to mucosalization were recorded. Complications, smoothness of postoperative course were reported. Both groups experienced a significant improvement in the VAS with no statistically significant difference in symptom improvement between the two groups except for olfaction where there was significant improvement in the powered group. Similarly, the two groups demonstrated a significant improvement in the objective parameters including polyp grade and saccharine clearance time changes, but no significant difference between the two groups was found. The operative time as well as the surgical conditions and dryness of the operative field score were significantly better in the powered group. There was a tendency for improvement in the number of endoscopic debridement and time to mucosalization in powered group when compared to conventional instruments group, but this did not reach statistical significance. The incidence of postoperative synechiae was significantly lower in powered endoscopic group. Powered endoscopic sinus surgery offers a better therapeutic approach for patients with sinonasal polyposis when compared to endoscopic surgery with the conventional instruments. It provides a bloodless dry operative field with better visualization for a more precise, less traumatic procedure with minimal intraoperative complications and shorter operative time. Additionally, patients have a smoother postoperative course, less incidence of synechiae, with a tendency for a faster healing. 相似文献
106.
STATEMENT OF PROBLEM: Little is known about how craniofacial bones that are distant from dental implants are loaded. Whether bone experiences different strain when implants of different diameters are loaded is unknown. PURPOSE: This study was designed to (1) characterize bone strain both adjacent to and distant from dental implants and (2) compare bone strain in response to the same loads on small-diameter and large-diameter implants. MATERIAL AND METHODS: On 4 edentulous, dry adult human skulls, the buccopalatal midpoint of the edentulous occlusal surface was marked unilaterally in the maxillary first molar area with a round bur. A hole for implant placement was prepared, and 2 self-tapping titanium implants (3.75 x 7 mm and 4 x 7 mm) were placed in the same location and at the same orientation, one after the other. A 4-mm-long titanium abutment was connected to the implant. Each implant was loaded 10 degrees lateral to its longitudinal axis, simulating a lateral occlusal force in 3 of the skulls. In skull 2, loading was along the longitudinal axis of the implant and simulated a vertical occlusal force. The magnitude of the ramp forces was 0 to 100 N. Uniaxial strain gages and/or 3-element strain rosettes were implanted in the supramolar cortical bone, the supraincisor cortical bone, the zygomaticomaxillary suture, and the zygomaticotemporal suture. All strain gages/rosettes were excited with 500 mV DC, and the output signals were recorded with a strain conditioner. Tensile strain was expressed as positive values and compressive strain as negative values. Student t tests were used to test for normal distribution of bone strain within each skull; Wilcoxon tests were applied for skewed distribution between small- and large-diameter implants and between 50-N and 100-N loads (P相似文献
107.
El-Morsy Z Khashaba MT Soliman Oel-S Yahia S El-Hady DA 《World journal of pediatrics : WJP》2011,7(4):326-330
Introduction
More than 200 mutations have been found in patients with Gaucher disease (GD) and some mutations usually have a high frequency in certain populations. Genotype/phenotype correlation in patients with GD has not been established. This study was designed to determine underlying mutations in Egyptian children with GD and to assess their relation to disease phenotypes. 相似文献108.
109.
Khairallah M Ben Yahia S Attia S Zaouali S Ladjimi A Messaoud R 《Eye (London, England)》2007,21(7):952-955
PURPOSE: To clarify the reason for the linear pattern of West Nile virus (WNV)-associated chorioretinitis. METHODS: The study included 12 patients (24 eyes) with WNV-associated chorioretinitis. All the patients underwent a complete ophthalmic evaluation, including dilated fundus examination, fundus photography, fluorescein angiography, and indocyanine green angiography. Characteristics of linear streaks, particularly their relationship to the course of retinal and choroidal vessels, and pattern of retinal nerve fibres, were analysed. RESULTS: All patients had bilateral multifocal chorioretinitis with linear clustering of chorioretinal lesions associated with a variable number of scattered lesions. Linear streaks, variable in number and length, originated from the optic disc or its vicinity in most cases. Their course in all cases appeared to closely follow the course of retinal nerve fibres, rather than that of retinal or choroidal vessels. CONCLUSIONS: Results of our study show that the linear pattern of WNV-associated chorioretinitis is related to retinal nerve fibres organization, suggesting a contiguous spread of WNV virus from central nerve system via the optic nerve fibres to the outer retina, retinal pigment epithelium, and choroid. 相似文献
110.
Remédiation cognitive et fonctionnement scolaire chez les enfants avec trouble du spectre autistique
M. Hajri Z. Abbes H. Ben Yahia M. Boudali A. Bouden A. Mrabet I. Amado 《Neuropsychiatrie de l'enfance et de l'adolescence》2019,67(1):19-24