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81.
Patients with breast carcinomas of the invasive cribriform (IC) histological type often have excellent prognosis. Nevertheless, prognostic markers such as CD44v3, v4, and v6 isoforms have never been evaluated in this histological type. Cases seen between 1996 and 2006 at two major public hospitals in Kuwait were reviewed. We selected the cases which still had enough tissue in the paraffin blocks, had pure rather than mixed typical histological type, did not receive hormonal or any other type of therapy prior to or at the time the tumor was excised, and which were grade 1, and stage IIA (T2, N0, M0). This is to control for confounding factors that could affect the degree of tumor expression of the above isoforms. Sections were immunostained using a highly sensitive roxidase-anti-peroxidase kit, and scoring of immunostaining was performed in a semi-quantitative manner as established in the literature. An extensive expression of the CD44v3 and v6 isoforms was seen in 83.3% of the IC tumours, while 83.3% lacked the expression of the v4 isoform. A significant association between the histological type and degree of expression of CD44 isoforms was found only with the v3 isoform. The degree of expression of the v3 isoform was significantly different in the IC tumors as compared to the papillary, invasive lobular, and invasive ductal (NOS) ones. There was a significant negative correlation (rs= - 0.201) between the expression of the v4 and v6 isoforms. IC tumors seem to have a strong expression of the prognostic markers v3 and v6 isoforms of the transmembrane molecule CD44, and to lack the expression of the v4 isoform. 相似文献
82.
Salman M. Toor Reem Saleh Varun Sasidharan Nair Rowaida Z. Taha Eyad Elkord 《Immunology》2021,162(1):30-43
Coronavirus disease 2019 (COVID‐19) is caused by SARS‐CoV‐2, a novel coronavirus strain. Some studies suggest that COVID‐19 could be an immune‐related disease, and failure of effective immune responses in initial stages of viral infection could contribute to systemic inflammation and tissue damage, leading to worse disease outcomes. T cells can act as a double‐edge sword with both pro‐ and anti‐roles in the progression of COVID‐19. Thus, better understanding of their roles in immune responses to SARS‐CoV‐2 infection is crucial. T cells primarily react to the spike protein on the coronavirus to initiate antiviral immunity; however, T‐cell responses can be suboptimal, impaired or excessive in severe COVID‐19 patients. This review focuses on the multifaceted roles of T cells in COVID‐19 pathogenesis and rationalizes their significance in eliciting appropriate antiviral immune responses in COVID‐19 patients and unexposed individuals. In addition, we summarize the potential therapeutic approaches related to T cells to treat COVID‐19 patients. These include adoptive T‐cell therapies, vaccines activating T‐cell responses, recombinant cytokines, Th1 activators and Th17 blockers, and potential utilization of immune checkpoint inhibitors alone or in combination with anti‐inflammatory drugs to improve antiviral T‐cell responses against SARS‐CoV‐2. 相似文献
83.
84.
Zhen-Yu Wu Young Joo Lee Yungil Shin Soojeong Choi Soo Yeon Baek Jung Whan Chun Loai Saleh Albinsaad Woo Jung Choi Namkug Kim BeomSeok Ko 《JOURNAL OF BREAST CANCER》2021,24(3):349
Tumor localization is challenging in the context of ductal carcinoma in situ (DCIS) treated with breast-conserving surgery. Conventional localization methods are generally performed under the guidance of ultrasonography or mammography and are rarely performed with magnetic resonance imaging (MRI), which is more sensitive than the aforementioned modalities in detecting DCIS. Here, we report the application of MRI-based individualized 3-dimensional (3D)-printed breast surgical guides (BSGs) for patients with breast cancer. We successfully resected indeterminate and suspicious lesions that were only detected using preoperative MRI, and the final histopathologic results confirmed DCIS with clear resection margins. MRI guidance combined with 3D-printed BSGs can be used for DCIS localization, especially for lesions easily detectable using MRI only. 相似文献
85.
Beata Bobrowska Wojciech Zasada Andrzej Surdacki Tomasz Rakowski Pawe? Kleczyński Jolanta ?wierszcz Olga Kruszelnicka Renata Rajtar-Salwa Saleh Arif Danuta Sorysz Dariusz Dudek Jacek S. Dubiel 《International journal of medical sciences》2013,10(10):1361-1366
Background. Patients with degenerative aortic stenosis (AS) exhibit elevated prevalence of coronary artery disease (CAD) and internal carotid artery stenosis (ICAS). Our aim was to investigate prevalence of significant CAD and ICAS in relation to demographic and cardiovascular risk profile among patients with severe degenerative AS.Methods. We studied 145 consecutive patients (77 men and 68 women) aged 49-91 years (median, 76) with severe degenerative AS who underwent coronary angiography and carotid ultrasonography in our tertiary care center. The patients were divided into two groups according to the presence of either significant CAD (n=86) or ICAS (n=22).Results. The prevalence of significant CAD or ICAS was higher with increasing number of traditional risk factors (hypertension, hypercholesterolemia, diabetes, smoking habit) and decreasing renal function. We found interactions between age and gender in terms of CAD (p=0.01) and ICAS (p=0.06), which was confirmed by multivariate approach. With the reference to men with a below-median age, the prevalence of CAD or ICAS increased in men aged >76 years (89% vs. 55% and 28% vs. 14%, respectively), whereas the respective percentages were lower in older vs. younger women (48% vs. 54% and 7% vs. 17%).Conclusions. In severe degenerative AS gender modulates the association of age with coronary and carotid atherosclerosis with its lower prevalence in women aged >76 years compared to their younger counterparts. This may result from a hypothetical “survival bias”, i.e., an excessive risk of death in very elderly women with severe AS and coexisting relevant coronary or carotid atherosclerosis. 相似文献
86.
Mohamed A. Salem Rasha Ali Radwan Eman Sherien Mostafa Saleh Alseekh Alisdair R. Fernie Shahira M. Ezzat 《RSC advances》2020,10(52):31511
Aging is an unavoidable fate that afflicts all life, during this process in mammals reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging. Therefore, the maintenance of antioxidant homeostasis is an important anti-aging strategy for skin. Nature has excellent anti-aging remedies that act externally as well as internally to delay the visual signs of aging. In view of this fact, the present study investigates the in vitro anti-aging activity of five medicinal plants belonging to phenolic rich families namely Rosmarinus officinalis, Lavandula officinalis, Matricaria chamomilla, Camellia sinensis and Pelargonium graveolens. The selected plants are those most frequently used in the preparation of ethnomedicinal recipes for the prevention or treatment of aging. The inhibitory effects of the ethanolic and aqueous extracts of the five selected plants on the activity of tyrosinase, elastase, and collagenase enzymes were investigated. Furthermore, the chemical composition of the plants and the antioxidant capacity of their extracts were assessed. The results showed that R. officinalis had the highest total phenolics content which was correlated with its potent antioxidant and anti-aging activities. To pinpoint the active metabolites in the tested extracts, we evaluated the metabolite variations using ultra-performance liquid chromatography coupled with high resolution electrospray ionization-tandem mass spectrometry (UPLC-HR-ESI-MS/MS). Multivariate data analysis (MVDA) revealed that R. officinalis significantly accumulated metabolites from the aromatic diterpenoid, flavonoid and phenolic acid classes. These results indicate that rosemary can be used for further development of topical preparations with anti-aging properties.Aging is an unavoidable fate that afflicts all life, during this process in mammals, reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging. 相似文献
87.
Veldtman Gruschen Possner Mathias Mohty Dania Issa Ziyad Alsaleh Monerah AlMarzoog AlJuhara Thaar Emmanual Shisamma Salam Yezan AlHabdan Mohammed Saleh Alsaied Tarek Rathod Rahul H. Siblini Ghassan Vriz Olga 《The international journal of cardiovascular imaging》2021,37(9):2651-2660
The International Journal of Cardiovascular Imaging - Abnormal atrial mechanics in biventricular circulations have been associated with elevated left heart filling pressures. Similar associations... 相似文献
88.
Altaf Hussain Shah Hesham Saleh Khalil Mohammed Zaheer Kola 《Saudi Dental Journal》2015,27(3):165-170
Automated Implantable Cardioverter Defibrillators (AICD), simply known as an Implantable Cardioverter Defibrillator (ICD), has been used in patients for more than 30 years. An Implantable Cardioverter Defibrillator (ICD) is a small battery-powered electrical impulse generator that is implanted in patients who are at a risk of sudden cardiac death due to ventricular fibrillation, ventricular tachycardia or any such related event. Typically, patients with these types of occurrences are on anticoagulant therapy. The desired International Normalized Ratio (INR) for these patients is in the range of 2–3 to prevent any subsequent cardiac event. These patients possess a challenge to the dentist in many ways, especially during oral surgical procedures, and these challenges include risk of sudden death, control of post-operative bleeding and pain.This article presents the dental management of a 60 year-old person with an ICD and concomitant anticoagulant therapy. The patient was on multiple medications and was treated for a grossly neglected mouth with multiple carious root stumps. This case report outlines the important issues in managing patients fitted with an ICD device and at a risk of sudden cardiac death. 相似文献
89.
Mohamed I. El-Anwar Salah A. Yousief Tarek A. Soliman Mahmoud M. Saleh Wael S. Omar 《Saudi Dental Journal》2015,27(4):201-207
Objective
This study aimed to evaluate stress patterns generated within implant-supported mandibular overdentures retained by two different attachment types: ball and socket and locator attachments.Materials and methods
Commercial CAD/CAM and finite element analysis software packages were utilized to construct two 3D finite element models for the two attachment types. Unilateral masticatory compressive loads of 50, 100, and 150 N were applied vertically to the overdentures, parallel to the longitudinal axes of the implants. Loads were directed toward the central fossa in the molar region of each overdenture, that linear static analysis was carried out to find the generated stresses and deformation on each part of the studied model.Results
According to FEA results the ball attachment neck is highly stressed in comparison to the locator one. On the other hand mucosa and cortical bone received less stresses under ball and socket attachment.Conclusions
Locator and ball and socket attachments induce equivalent stresses on bone surrounding implants. Locator attachment performance was superior to that of the ball and socket attachment in the implants, nylon caps, and overdenture. Locator attachments are highly recommended and can increase the interval between successive maintenance sessions. 相似文献90.
Heba J. Sabbagh Nicola P. Innes Bahauddin I. Sallout Najlaa M. Alamoudi Mustafa A. Hamdan Nasir Alhamlan Amaal I. Al-Khozami Fatma D. Abdulhameed Jumana Y. Al-Aama Peter A. Mossey 《Saudi medical journal》2015,36(9):1076-1083