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81.
Vaginal cancer represents about 1-2% of the genital tract malignancies. Most cases represent metastasis from the cervix, endometrium or colon. Metastasis of salivary duct carcinoma to the vagina has not been previously reported. Salivary duct carcinoma (SDC) is a rare, highly aggressive tumor that most often involves the parotid gland. On presentation, SDC is metastasized to the regional lymph nodes in about 40% of cases. We report a case of metastatic salivary duct carcinoma presenting as a vaginal mass with bleeding. Diagnosis was confirmed by the histological appearance in addition to immunohistochemistry. To our knowledge this is the first reported case of vaginal metastasis from SDC. Small-sized primaries might be ignored by the patient, specially in the older age group, probably due to lack of manifesting symptoms like pain and bleeding. Some cancers, like SDC, have various histologic patterns in different areas of the tumor. Careful examinations of multiple sections, in addition to an immunohistochemical panel, and histologic comparison of all lesions are keys to a correct diagnosis. 相似文献
82.
Sabbah Ataya Mohamed M. Z. Ahmed Mohamed M. El-Sayed Seleman Khalil Hajlaoui Fahamsyah H. Latief Ahmed M. Soliman Yousef G. Y. Elshaghoul Mohamed I. A. Habba 《Materials》2022,15(4)
In the current study, a 2 mm thick low-carbon steel sheet (A283M—Grade C) was joined with a brass sheet (CuZn40) of 1 mm thickness using friction stir spot welding (FSSW). Different welding parameters including rotational speeds of 1000, 1250, and 1500 rpm, and dwell times of 5, 10, 20, and 30 s were applied to explore the effective range of parameters to have FSSW joints with high load-carrying capacity. The joint quality of the friction stir spot-welded (FSSWed) dissimilar materials was evaluated via visual examination, tensile lap shear test, hardness test, and macro- and microstructural investigation using SEM. Moreover, EDS analysis was applied to examine the mixing at the interfaces of the dissimilar materials. Heat input calculation for the FSSW of steel–brass was found to be linearly proportional with the number of revolutions per spot joint, with maximum heat input obtained of 11 kJ at the number of revolutions of 500. The temperature measurement during FSSW showed agreement with the heat input dependence on the number of revolution. However, at the same revolutions of 500, it was found that the higher rotation speed of 1500 rpm resulted in higher temperature of 583 °C compared to 535 °C at rotation speed of 1000 rpm. This implies the significant effect for the rotation speed in the increase of temperature. The macro investigations of the friction stir spot-welded joints transverse sections showed sound joints at the different investigated parameters with significant joint ligament between the steel and brass. FSSW of steel/brass joints with a number of revolutions ranging between 250 to 500 revolutions per spot at appropriate tool speed range (1000–1500 rpm) produces joints with high load-carrying capacity from 4 kN to 7.5 kN. The hardness showed an increase in the carbon steel (lower sheet) with maximum of 248 HV and an increase of brass hardness at mixed interface between brass and steel with significant reduction in the stir zone hardness. Microstructural investigation of the joint zone showed mechanical mixing between steel and brass with the steel extruded from the lower sheet into the upper brass sheet. 相似文献
83.
Norihiko Kamioka Vasilis Babaliaros Michael Andrew Morse Tiberio Frisoli Stamatios Lerakis Jose Miguel Iturbe Jose Binongo Frank Corrigan Altayyeb Yousef Patrick Gleason John A. Wells Hope Caughron Andy Dong Evelio Rodriguez Bradley Leshnower William O’Neill Gaetano Paone Marvin Eng Adam Greenbaum 《JACC: Cardiovascular Interventions》2018,11(12):1131-1138
Objectives
There are minimal data regarding clinical outcomes and echocardiographic findings after transcatheter mitral valve-in-valve replacement (TMVR) compared with redo surgical mitral valve replacement (SMVR).Background
TMVR therapy has emerged as therapy for a degenerated bioprosthetic valve failure.Methods
The authors retrospectively identified patients with degenerated mitral bioprostheses who underwent redo SMVR or TMVR at 3 U.S. institutions. The authors compared clinical and echocardiographic outcomes of patients who had TMVR with those of patients who underwent redo SMVR.Results
Sixty-two patients underwent TMVR and 59 patients underwent SMVR during the study period. Mean age and the Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) scores were significantly higher in patients with TMVR than in those with SMVR (age 74.9 ± 9.4 years vs. 63.7 ± 14.9 years; p < 0.001; STS PROM 12.7 ± 8.0% vs. 8.7 ± 10.1%; p < 0.0001). Total procedure time, intensive care unit hours, and post-procedure length of stay were all significantly shorter in the TMVR group. There was no difference in mortality at 1 year between the 2 groups (TMVR 11.3% vs. SMVR 11.9%; p = 0.92). Mean mitral valve pressure gradient and the grade of mitral regurgitation (MR) were similar between the TMVR group and the SMVR group (mitral valve pressure gradient 7.1 ± 2.5 mm Hg vs. 6.5 ± 2.5 mm Hg; p = 0.42; MR [≥moderate] 3.8% vs. 5.6%; p = 1.00) at 30 days. At 1 year, the mitral valve pressure gradient was higher in the TMVR group (TMVR 7.2 ± 2.7 vs. SMVR 5.5 ± 1.8; p = 0.01), although there was no difference in the grade of MR.Conclusions
Despite the higher STS PROM in TMVR patients, there was no difference in 1-year mortality between the TMVR and SMVR groups. Echocardiographic findings after TMVR were similar to SMVR at 30 days. There was a statistically significant difference in mitral gradient at 1 year, though this is likely not clinically important. TMVR may be an alternative to SMVR in patients with previous mitral bioprosthetic valves. 相似文献84.
85.
Aim: We assess the accuracy of torque controllers after several aging processes and the bacterial leakage on implant-abutment complexes (IAC). Methods: A total of 12 spring-type and 12 friction-type torque controllers and 48 IAC (24 conical and 24 hexagonal connections) were evaluated. Chemical, mechanical, temperature, and pressure-aging methods were applied individually to replicate clinical use. Torque controller accuracy was analyzed before and after aging using a calibrated gauge. To assess bacterial leakage, the IAC were suspended in a bacterial medium for 24 h. Direct Contact Test (DCT) and Polymerase Chain Reaction Test (RT-PCR) analyzed the infiltration of F. nucleatum and P. gingivalis into the IAC micro-gap. Results: A significant decrease in torque after 10 days of aging was found. The spring-type torque controller was affected the most, regardless of the aging method (P < 0.05). PCR results indicated that all groups exhibited significantly more bacterial leakage, regardless of the method used (P < 0.05). The conical IAC demonstrated more bacterial leakage of P. gingivalis compared with the hexagonal IAC (P = 0.07). DCT found bacterial growth in the IAC only before aging and was not identified after aging. Conclusion: Aging affects torque accuracy. A reduction in force was noticed after 10 days. The conical IAC exhibits more bacterial leakage, although this was not statistically significant. 相似文献
86.
Adekunle Dawodu Yousef M. Abdulrazzaq Abdulbari Bener Inge Kappel Larry Liddle Mani Varghese 《American journal of human biology》1996,8(3):341-345
A prospective study of biological factors for low birthweight (LBW) among UAE nationals in the Al Ain Medical District was undertaken from 15 January 1992 to 14 January 1993, using a case control method. All 293 mothers of LBW infants and an equal number of mothers of the next normal weight infants born after the LBW infant were studied. Of the 3,485 live births, 293 (8.4%) were LBW (less than 2,500 g). Maternal age less than 25 years, lighter weight at booking, nulliparity, first cousin marriage and short interpregnancy interval (IPI) of 3 months or less significantly increased the risk of LBW in this population. After adjusting for other biologic confounders, only low maternal weight and short IPI significantly increased the risk of LBW. Modification of these biologic risk factors would help to reduce the incidence of LBW among the UAE population. © 1996 Wiley-Liss, Inc. 相似文献
87.
Tamer A. Mesallam Medhat Yousef Ilona Anderson Yassin Abdelsamad Sara Alkhamiss Abdulrahman Alsanosi 《Saudi medical journal》2021,42(9):1031
Objectives:To validate an Arabic version of the LittlEARS® Early Speech Production Questionnaire (LEESPQ), which assesses the early development of speech and language in infants between 0 and 18 months, in Arabic-speaking children with normal hearing in Saudi Arabia.Methods:This is a cross-sectional study conducted in the city of Riyadh, Saudi Arabia between September and December 2020. Parents completed the LEESPQ regarding their child’s speech production development. To assess the ability of normal hearing children aged 0-18 months in developing speech and language production, a norm curve has been generated based on the standardized values that were calculated from the Arabic normal-hearing data set.Results:A total of 198 questionnaires were analyzed. The total score on the LEESPQ correlated with age, gender, and bilingualism. A norm curve for early speech production in children with normal hearing was created.Conclusion:The Arabic version of LEESPQ appears to be a valid questionnaire that can be used in the assessment of early language and speech development of Arabic-speaking children with normal hearing in the age range of 0-18 months. The Arabic version of the LEESPQ might also be a useful tool to detect developmental delays and hearing disorders in young children. 相似文献
88.
Elham Bahreini Yousef Rezaei-Chianeh Mohsen Nabi-Afjadi 《The review of diabetic studies : RDS》2021,17(1):1
Uncontrolled or chronic hyperglycemia causes kidney failure induced by the dysfunction of biomolecules and upregulation of inflammatory cytokines and growth factors. The reninangiotensin system (RAS) is incorporated in the regulation of renal hemodynamics. In a healthy state, local RAS is independent of systemic RAS. However, in pathological conditions such as chronic hyperglycemia, angiotensin II (Ang II) increases locally and causes tissue damage, mainly through the induction of oxidative stress, inflammation, and upregulation of some growth factors and their receptors. Such tissue events may cause disruption of the glomerular filtration barrier, thickening and hypertrophy of the glomerular basement membrane, microvascular hyperpermeability, proteinuria, and finally decrease in the glomerular filtration rate (GFR). Reduced GFR causes the kidney to sense falsely a low blood pressure condition and respond to it by stimulating systemic and local RAS. Therefore, patients with diabetic nephropathy (DN) suffer from chronic hypertension. In contrast to local RAS, there are alternative pathways in the kidney that act protectively by reducing tissue Ang II. Such autoregulatory and protective mechanisms are weakened in chronic kidney disease. Previously, it was presumed that systemic RAS inhibitors such as ACE inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) could prevent renal damage by controlling blood pressure and proteinuria. However, the progression of renal failure to end-stage renal disease (ESRD), despite such treatments, indicates the presence of factors other than Ang II. This review highlights the molecular mechanism in renal disease and discusses pharmaceutical and therapeutic approaches. 相似文献
89.
Tantawy Azza Abdel Gawad Adly Amira Abdel Moneam Abdeen Mai Seif El Din Salah Nouran Yousef 《Neurogenetics》2020,21(3):159-167
neurogenetics - Evidence about the link between glucocerebrosidase (GCase) and parkinsonism is growing. Parkinsonism was described in adult type 1 Gaucher disease (GD); few case reports described... 相似文献
90.
Ashley Di Meo Ihor Batruch Marshall D. Brown Chuance Yang Antonio Finelli Michael A. Jewett Eleftherios P. Diamandis George M. Yousef 《International journal of cancer. Journal international du cancer》2020,146(8):2315-2325
Renal cell carcinoma (RCC) is frequently diagnosed incidentally as an early-stage small renal mass (SRM; pT1a, ≤4 cm). Overtreatment of patients with benign or clinically indolent SRMs is increasingly common and has resulted in a recent shift in treatment recommendations. There are currently no available biomarkers that can accurately predict clinical behavior. Therefore, we set out to identify early biomarkers of RCC progression. We employed a quantitative label-free liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) proteomics approach and targeted parallel-reaction monitoring to identify and validate early, noninvasive urinary biomarkers for RCC-SRMs. In total, we evaluated 115 urine samples, including 33 renal oncocytoma (≤4 cm) cases, 30 progressive and 26 nonprogressive clear cell RCC (ccRCC)-SRM cases, in addition to 26 healthy controls. We identified six proteins, which displayed significantly elevated expression in clear cell RCC-SRMs (ccRCC-SRMs) relative to healthy controls. Proteins C12ORF49 and EHD4 showed significantly elevated expression in ccRCC-SRMs compared to renal oncocytoma (≤4 cm). Additionally, proteins EPS8L2, CHMP2A, PDCD6IP, CNDP2 and CEACAM1 displayed significantly elevated expression in progressive relative to nonprogressive ccRCC-SRMs. A two-protein signature (EPS8L2 and CCT6A) showed significant discriminatory ability (areas under the curve: 0.81, 95% CI: 0.70–0.93) in distinguishing progressive from nonprogressive ccRCC-SRMs. Patients (Stage I–IV) with EPS8L2 and CCT6A mRNA alterations showed significantly shorter overall survival (p = 1.407 × 10−6) compared to patients with no alterations. Our in-depth proteomic analysis identified novel biomarkers for early-stage RCC-SRMs. Pretreatment characterization of urinary proteins may provide insight into early RCC progression and could potentially help assign patients to appropriate management strategies. 相似文献