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991.
Potentially malignant disorders of the oral cavity: Current practice and future directions in the clinic and laboratory
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Kalen R. Dionne Saman Warnakulasuriya Rosnah Binti Zain Sok Ching Cheong 《International journal of cancer. Journal international du cancer》2015,136(3):503-515
Despite commendable progress in the prevention, detection, and treatment of a wide variety of solid tumor types, oral squamous cell carcinoma (OSCC) remains a significant health burden across the globe. OSCC carcinogenesis involves accumulation of genetic alterations that coincide with the multistep malignant transformation of normal oral epithelium. OSCC is often first diagnosed at late stages of the disease (advanced regional disease and/or metastasis). Delayed diagnosis precludes successful treatment and favorable outcomes. In clinical practice, opportunities exist to identify patients with oral potentially malignant disorders (OPMDs), which precede the development of cancer. This review addresses the current status of laboratory and clinical research on OPMDs, with emphasis on leukoplakia and erythroplakia. OSF is also presented, though there is a paucity of published studies on this disorder. We focus on findings that could translate into earlier diagnosis and more efficacious treatment of those lesions with significant malignant potential. We explore how markers of OPMD malignant transformation might be implemented into current diagnostic practice to help clinicians objectively stratify patients into treatment/follow‐up groups according to relative risk. We provide an overview of recently concluded and ongoing OPMD chemoprevention trials. We describe laboratory OPMD models that can be used to not only to reveal the genetic and molecular intricacies of oral cancer but also to develop novel screening methods and therapeutic approaches. Finally, we call for targeted screening programs of at‐risk populations in order to facilitate diagnosis and treatment of OPMD and early OSCC. 相似文献
992.
Holden JT; Geller RB; Farhi DC; Holland HK; Stempora LL; Phillips CN; Bray RA 《Blood》1995,86(1):60-65
Thy-1 (CDw90) is a phosphatidylinositol-anchored cell surface molecule which, when coexpressed with CD34 in normal human bone marrow, identifies a population of immature cells that includes putative hematopoietic stem cells. To date, the characterization of Thy-1 expression has been confined largely to normal tissues and cell lines. In this study, we evaluated the frequency and intensity of Thy-1 expression as defined by reactivity with the anti-Thy-1 antibody 5E10 in 38 cases of CD34+ acute leukemia (21 acute myelogenous leukemia [AML], 8 chronic myelogenous leukemia [CML] in blast crisis, and 9 acute lymphoblastic leukemia [ALL]). In 34 of 38 cases (89%) the CD34+ cells lacked expression of the Thy-1 antigen. High-density Thy-1 expression was found in 1 case of CML in lymphoid blast crisis, and low- density Thy-1 expression was identified on a portion of the leukemic cells in 2 cases of AML with myelodysplastic features, and 1 case of CML in myeloid blast crisis, suggesting a possible correlation between Thy-1 expression and certain instances of stem cell disorders such as CML and AML with dysplastic features. In contrast, the dissociation of Thy-1 and CD34 expression in the majority of acute leukemias studied suggests that the development of these leukemias occurs at a later stage than the hematopoietic stem cell. Characterization of Thy-1 expression in acute leukemia may eventually provide insights into the origin of the disease. In addition, separation of leukemic blasts from normal stem cells based on Thy-1 expression may prove useful in assessing residual disease, as well as in excluding leukemic blasts from stem cell preparations destined for autologous bone marrow or peripheral stem cell transplantation. 相似文献
993.
Background: Implant supported restorations (ISRs) for the single implant may be cement retained or screw retained. Limited scientific evidence exists to support the superiority of a retention type for either implant or prosthetic success. The aim of this study was to assess preferences of Australian prosthodontists when restoring single implants. In particular, clinical practices for cross‐pin retained implant supported restorations for a single implant were investigated. Methods: A written questionnaire comprised of seven questions, some of which had multiple parts and of both open‐ and closed‐format, was sent to 124 Australian prosthodontists. The questionnaire asked recipients to identify: (1) their preference for retention choice when restoring a single implant; (2) the frequency of use; and (3) clinical practice when restoring a cross‐pin retained restoration. Results: Seventy‐seven per cent of respondents indicated that direct to fixture (DTF) retention was their first preference. DTF retention was also the most frequently employed restoration for single implants. Respondents indicated that cross‐pinned ISRs are employed to maintain retrievability or when DTF is not possible. The majority of respondents indicated they always or sometimes use a gasket with cross‐pin retained restorations, though gasket type varied. Thirty‐eight respondents (31%) indicated that they would never use a cross‐pinned retained restoration for a single ISR. Conclusions: Australian prosthodontists prefer, and more frequently restore single implants, using DTF retention. Queensland prosthodontists prefer cement retained ISRs. In comparison, cross‐pinned restorations tend to be the least favoured and least used retention type. In addition, variation in opinion exists regarding the need for a gasket and type of gasket to be placed. 相似文献
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995.
Improvements in medical facilities have helped a large number of clinically severe hemoglobin E (HbE)-β-thalassemia patients reach adulthood. Consequently, there is a new challenge, that of managing women with HbE-β-thalassemia during pregnancy. In particular, they have a high risk of abortion, preterm delivery, intrauterine growth restriction, and thromboembolism. A 27-year-old HbE-β-thalassemia patient on regular transfusion, who was splenectomized and heptatitis C (HCV)-positive, conceived for the first time without any infertility treatment. However, there was incomplete abortion with heavy bleeding at 3 months of gestation, which required bilateral uterine artery angiography. The angiogram showed the left uterine artery to be moderately hypertrophied. This was embolized with 300-500 micron polyvinyl alcohol (PVA) to stop the bleeding. Soon after, she conceived again with a twin pregnancy, and at 33.3 weeks of gestation, there was a normal delivery of twin girls without any postpartum hemorrhage or perineal tear. Both babies were given prematurity care. The mother and children were both normal up till the last follow-up 18 months after delivery, and both the girls are HbE heterozygous. Thorough monitoring of endocrine functions along with proper management of transfusions and iron overload can help in reducing the complications related to pregnancy in these patients.KEY WORDS: Hemoglobin E (HbE)-β-thalassemia, hydroxyurea, iron chelation, twin pregnancy 相似文献
996.
997.
998.
Muneerah Smith Houari B. Abdesselem Michelle Mullins Ti-Myen Tan Andrew J. M. Nel Maryam A. Y. Al-Nesf Ilham Bensmail Nour K. Majbour Nishant N. Vaikath Adviti Naik Khalid Ouararhni Vidya Mohamed-Ali Mohammed Al-Maadheed Darien T. Schell Seanantha S. Baros-Steyl Nur D. Anuar Nur H. Ismail Priscilla E. Morris Raja N. R. Mamat Nurul S. M. Rosli Arif Anwar Kavithambigai Ellan Rozainanee M. Zain Wendy A. Burgers Elizabeth S. Mayne Omar M. A. El-Agnaf Jonathan M. Blackburn 《Viruses》2021,13(5)
The COVID-19 pandemic has affected all individuals across the globe in some way. Despite large numbers of reported seroprevalence studies, there remains a limited understanding of how the magnitude and epitope utilization of the humoral immune response to SARS-CoV-2 viral anti-gens varies within populations following natural infection. Here, we designed a quantitative, multi-epitope protein microarray comprising various nucleocapsid protein structural motifs, including two structural domains and three intrinsically disordered regions. Quantitative data from the microarray provided complete differentiation between cases and pre-pandemic controls (100% sensitivity and specificity) in a case-control cohort (n = 100). We then assessed the influence of disease severity, age, and ethnicity on the strength and breadth of the humoral response in a multi-ethnic cohort (n = 138). As expected, patients with severe disease showed significantly higher antibody titers and interestingly also had significantly broader epitope coverage. A significant increase in antibody titer and epitope coverage was observed with increasing age, in both mild and severe disease, which is promising for vaccine efficacy in older individuals. Additionally, we observed significant differences in the breadth and strength of the humoral immune response in relation to ethnicity, which may reflect differences in genetic and lifestyle factors. Furthermore, our data enabled localization of the immuno-dominant epitope to the C-terminal structural domain of the viral nucleocapsid protein in two independent cohorts. Overall, we have designed, validated, and tested an advanced serological assay that enables accurate quantitation of the humoral response post natural infection and that has revealed unexpected differences in the magnitude and epitope utilization within a population. 相似文献
999.
New Activities for Isolated Compounds from Convolvulus austro‐aegyptiacus as Anti‐ulcerogenic,Anti‐Helicobacter pylori and Their Mimic Synthesis Using Bio‐guided Fractionation
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Amani S. Awaad Asmaa A. Al‐Rifai Reham M. El‐Meligy Ahmed M. Alafeefy Mohamed E. Zain 《Phytotherapy research : PTR》2015,29(9):1311-1316
Bio‐guided fractionation of the total alcoholic extract of Convolvulus austro‐aegyptiacus was screened for its anti‐ulcerogenic activity, using an absolute‐ethanol‐induced ulcer model at 500 and 1000 mg/kg doses. Two compounds were isolated from the butanol extract of C. austro‐aegyptiacus and identified by 1H and 13C nuclear magnetic resonance as scopoletin and scopolin. The isolated compounds (50 mg/kg) showed a remarkable anti‐ulcerogenic activity because they exhibited control‐ulcer protection by 16.7% and 90.8%, respectively. The acute toxicity study showed that the extract is highly safe; the median lethal dose (LD50) was more than 4000 mg/kg. Moreover, the obtained results were confirmed by the sub‐chronic toxicity because the rats that have been administered 1000 mg/kg of the extract for 15 consecutive days showed no alteration in the liver and kidney functions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.
A Physical Heart Failure Simulation System Utilizing the Total Artificial Heart and Modified Donovan Mock Circulation
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Jessica R. Crosby Katrina J. DeCook Phat L. Tran Edward Betterton Richard G. Smith Douglas F. Larson Zain I. Khalpey Daniel Burkhoff Marvin J. Slepian 《Artificial organs》2017,41(7):E52-E65
With the growth and diversity of mechanical circulatory support (MCS) systems entering clinical use, a need exists for a robust mock circulation system capable of reliably emulating and reproducing physiologic as well as pathophysiologic states for use in MCS training and inter‐device comparison. We report on the development of such a platform utilizing the SynCardia Total Artificial Heart and a modified Donovan Mock Circulation System, capable of being driven at normal and reduced output. With this platform, clinically relevant heart failure hemodynamics could be reliably reproduced as evidenced by elevated left atrial pressure (+112%), reduced aortic flow (?12.6%), blunted Starling‐like behavior, and increased afterload sensitivity when compared with normal function. Similarly, pressure‐volume relationships demonstrated enhanced sensitivity to afterload and decreased Starling‐like behavior in the heart failure model. Lastly, the platform was configured to allow the easy addition of a left ventricular assist device (HeartMate II at 9600 RPM), which upon insertion resulted in improvement of hemodynamics. The present configuration has the potential to serve as a viable system for training and research, aimed at fostering safe and effective MCS device use. 相似文献