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91.
92.
Expression of Salivary S100A7 Levels in Stage I Oral Submucous Fibrosis: A Clinical and Laboratory Study 下载免费PDF全文
Muhammad Arsalan RaffatNaila Irum HadiOsama AlghamdiKhulud Abdulrahman Al-AaliModhi Al DeebTariq AbduljabbarFahim Vohra 《Asian Pacific journal of cancer prevention》2020,21(4):1115-1119
Background: Oral submucous fibrosis (OSF) is a chronic debilitating condition characterized by juxta-epithelial fibrosis. The main etiological agent associated with the high-risk precancerous condition is areca nut use. S100A7 is a member of the largest calcium-binding proteins exclusively found in vertebrates and are associated with the regulation of numerous intracellular and extracellular functions. The aim of this study was to investigate the expression of protein S100A7 in salivary samples of individuals with stage I OSF and healthy controls. Methods: This study included 63 participants, 30 of whom had OSF stage I and 33 healthy controls. Nonprobability quota sampling technique was utilized for recruitment of the study participants. A structured baseline questionnaire was used to collect demographic data. Saliva samples were collected by passive droll technique in a sterile container. Salivary levels of S100A7 were quantified by enzyme-linked immunosorbent assay. For the normality of the data Shapiro Wilk test was performed. Student t-test was commuted to evaluate the expression of S100A7 protein expression between both the study groups. Results: The mean salivary S100A7 value for stage I OSF group was 0.334 ng/ml, compared to 0.172 ng/ml for healthy controls. Student t-test reported a statistically significant difference, indicating higher levels of S100A7 in stage I OSF group than in healthy controls (p < 0.001). In the individual group analysis, a significant negative correlation was found between salivary S100A7 and duration of areca nut use (r = –0.45, p = 0.009) and gutka chewing (r = –0.20, p = 0.03), while a significant positive correlation was found between salivary S100A7 and mouth opening (r = 0.03, p = 0.04). Conclusions: Higher levels of S100A7 protein level was seen in stage I OSF group in comparison to the healthy individuals. Results of our study suggest that S100A7 could be used as a surrogate assessment to identify patients at risk of OSF development. 相似文献
93.
Ebtissam Saleh Al-Meghaiseeb Mulfi Mubarak Al-Otaibi Abdulrahman Al-Robayan Reem Al-Amro Ahmd Saad Al-Malki Misbahul Arfin Abdulrahman K Al-Asmari 《World journal of gastroenterology : WJG》2015,21(3):897-904
AIM:To study the association of apolipoprotein E(APOE) polymorphisms with the susceptibility ofinflammatory bowel disease(IBD) in Saudi patients.METHODS:APOE genotyping was performed to evaluate the allele and genotype frequencies in 378 Saudi subjects including IBD patients with ulcerative colitis(n = 84) or Crohn's disease(n = 94) and matched controls(n = 200) using polymerase chain reaction and reverse-hybridization techniques.RESULTS:The frequencies of the APOE ε2 allele and ε2/ε3 and ε2/ε4 genotypes were significantly higher in IBD patients than in controls(P 0.05),suggesting that the ε2 allele and its heterozygous genotypes may increase the susceptibility to IBD.On the contrary,the frequencies of the ε3 allele and ε3/ε3 genotype were lower in IBD patients as compared to controls,suggesting a protective effect of APOE ε3 for IBD.The prevalence of the ε4 allele was also higher in the patient group compared to controls,suggesting that the ε4 allele may also increase the risk of IBD.Our results also indicated that the APOE ε4 allele was associated with an early age of IBD onset.No effect of gender or type of IBD(familial or sporadic) on the frequency distribution of APOE alleles and genotypes was noticed in this study.CONCLUSION:APOE polymorphism is associated with risk of developing IBD and early age of onset in Saudi patients,though further studies with a large-size population are warranted. 相似文献
94.
Aisha T. Liferidge Jane H. Brice MD MPH Barbara A. Overby MSN RN EMT-P Kelly R. Evenson PhD 《Prehospital emergency care》2004,8(4):384
Objective
Early stroke recognition optimizes patients' opportunities to benefit from therapeutic options. Prehospital stroke recognition is suboptimal. If 9-1-1 dispatchers used stroke-identification tools, prehospital stroke recognition might occur more rapidly and accurately. The Cincinnati Prehospital Stroke Scale (CPSS) is a brief, effective tool used by emergency medical services and hospital personnel to identify stroke. The study's goal was to determine whether laypersons could be instructed to use the CPSS over the telephone.Methods
Adult visitors (laypersons) to a tertiary care emergency department were enrolled. Using a mock patient, laypersons were instructed to use the CPSS via telephone by an investigator simulating a 9-1-1 dispatcher. The patient randomly portrayed clinically normal and abnormal patient types. The layperson's ability to convey CPSS instructions to the patient and relay findings to the investigator was scored.Results
Seventy laypersons were enrolled (35 each for normal and abnormal patient types). Average age was 48 years, 63% were female, and 40% never attended college. Facial droop and speech instructions were administered with 100% accuracy. Arm drift instructions were administered with 99% accuracy. Layperson accuracies for interpreting findings were 93% for facial droop, 93% for arm drift, and 97% for speech. Overall, stroke symptoms were detected with 94% sensitivity (95% CI 87, 100) and 83% specificity (95% CI 70, 95).Conclusion
Laypersons correctly administered and interpreted the CPSS when directed to do so over the telephone by a trained investigator. These findings suggest that the CPSS may be a useful tool in early prehospital detection of stroke by dispatchers. 相似文献95.
96.
Lutfiah Al-Turk James Wawrzynski Su Wang Paul Krause George M. Saleh Hend Alsawadi Abdulrahman Zaid Alshamrani Tunde Peto Andrew Bastawrous Jingren Li Hongying Lilian Tang 《Eye (London, England)》2022,36(3):524
BackgroundIn diabetic retinopathy (DR) screening programmes feature-based grading guidelines are used by human graders. However, recent deep learning approaches have focused on end to end learning, based on labelled data at the whole image level. Most predictions from such software offer a direct grading output without information about the retinal features responsible for the grade. In this work, we demonstrate a feature based retinal image analysis system, which aims to support flexible grading and monitor progression.MethodsThe system was evaluated against images that had been graded according to two different grading systems; The International Clinical Diabetic Retinopathy and Diabetic Macular Oedema Severity Scale and the UK’s National Screening Committee guidelines.ResultsExternal evaluation on large datasets collected from three nations (Kenya, Saudi Arabia and China) was carried out. On a DR referable level, sensitivity did not vary significantly between different DR grading schemes (91.2–94.2.0%) and there were excellent specificity values above 93% in all image sets. More importantly, no cases of severe non-proliferative DR, proliferative DR or DMO were missed.ConclusionsWe demonstrate the potential of an AI feature-based DR grading system that is not constrained to any specific grading scheme.Subject terms: Diagnosis, Medical imaging 相似文献
97.
Jamie A. Moore Jayna J. Mistry Charlotte Hellmich Rebecca H. Horton Edyta E. Wojtowicz Aisha Jibril Matthew Jefferson Thomas Wileman Naiara Beraza Kristian M. Bowles Stuart A. Rushworth 《The Journal of clinical investigation》2022,132(5)
The bone marrow (BM) microenvironment regulates acute myeloid leukemia (AML) initiation, proliferation, and chemotherapy resistance. Following cancer cell death, a growing body of evidence suggests an important role for remaining apoptotic debris in regulating the immunologic response to and growth of solid tumors. Here, we investigated the role of macrophage LC3–associated phagocytosis (LAP) within the BM microenvironment of AML. Depletion of BM macrophages (BMMs) increased AML growth in vivo. We show that LAP is the predominate method of BMM phagocytosis of dead and dying cells in the AML microenvironment. Targeted inhibition of LAP led to the accumulation of apoptotic cells (ACs) and apoptotic bodies (ABs), resulting in accelerated leukemia growth. Mechanistically, LAP of AML-derived ABs by BMMs resulted in stimulator of IFN genes (STING) pathway activation. We found that AML-derived mitochondrial damage–associated molecular patterns were processed by BMMs via LAP. Moreover, depletion of mitochondrial DNA (mtDNA) in AML-derived ABs showed that it was this mtDNA that was responsible for the induction of STING signaling in BMMs. Phenotypically, we found that STING activation suppressed AML growth through a mechanism related to increased phagocytosis. In summary, we report that macrophage LAP of apoptotic debris in the AML BM microenvironment suppressed tumor growth. 相似文献
98.
Abdulrahman Alshalani Lisa van Manen Margit Boshuizen Robin van Bruggen Jason P. Acker Nicole P. Juffermans 《Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie》2022,49(2):98
BackgroundObservational studies suggest that sex-mismatched transfusion is associated with increased mortality. Mechanisms driving mortality are not known but may include endothelial activation. The aim of this study is to investigate the effects of sex-mismatched red blood cell (RBC) transfusions on endothelial cell activation markers in critically ill patients.Study Design and MethodsIn patients admitted to the intensive care unit who received a single RBC unit, blood samples were drawn before (T<sub>0</sub>), 1 h after (T<sub>1</sub>), and 24 h after transfusion (T<sub>24</sub>) for analysis of soluble syndecan-1, soluble intercellular adhesion molecule-1, soluble thrombomodulin (sTM), von Willebrand factor antigen, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNFα). Changes in the levels of these factors were compared between sex-matched and sex-mismatched groups.ResultsOf 69 included patients, 32 patients were in the sex-matched and 37 patients were in the sex-mismatched group. Compared to baseline, sex-matched transfusion was associated with significant reduction in sTM level (p value = 0.03). Between-group comparison showed that levels of syndecan-1 and sTM were significantly higher in the sex-mismatched group compared to the sex-matched group at T<sub>24</sub> (p value = 0.04 and 0.01, respectively). Also, TNFα and IL-6 levels showed a statistically marginal significant increase compared to baseline in the sex-mismatched group at T<sub>24</sub> (p value = 0.06 and 0.05, respectively), but not in the sex-matched group.DiscussionTransfusion of a single sex-mismatched RBC unit was associated with higher syndecan-1 and sTM levels compared to transfusion of sex-matched RBC unit. These findings may suggest that sex-mismatched RBC transfusion is associated with endothelial activation. 相似文献
99.
van Karnebeek Clara D. Blydt-Hansen Ingrid Matthews Allison M. Avramovic Vladimir Price Magda Drogemoller Britt Shyr Casper Lee Jessica Mwenifumbo Jill Ghani Aisha Stockler Sylvia Friedman Jan M. Lehman Anna Ross Colin J. Wasserman Wyeth W. Tarailo-Graovac Maja Horvath Gabriella A. 《Neurogenetics》2021,22(4):251-262
neurogenetics - Monoamine neurotransmitter disorders present predominantly with neurologic features, including dystonic or dyskinetic cerebral palsy and movement disorders. Genetic conditions that... 相似文献
100.
Ahmed M. Abu El‐Asrar Suhail Hemachandran Hani S. Al‐Mezaine Dustan Kangave Abdulrahman M. Al‐Muammar 《Acta ophthalmologica. Supplement》2012,90(8):e603-e608
Purpose: To study the effectiveness of mycophenolate mofetil (MMF) as first‐line therapy combined with systemic corticosteroids in acute uveitis associated with Vogt–Koyanagi–Harada (VKH) disease. The outcomes in this group were compared with those of another group of patients with VKH disease who were treated with corticosteroid monotherapy or with delayed addition of immunomodulatory therapy. Methods: This prospective study included 19 patients (38 eyes) diagnosed with acute uveitis associated with VKH disease. Results: The mean follow‐up period was 27.0 ± 11.1 months (range 16–54 months). Corticosteroid‐sparing effect was achieved in all patients. The mean interval between starting treatment and tapering prednisone to 10 mg or less daily was 5.1 ± 1.2 months (range 3–7 months). Ten (53%) patients discontinued treatment without relapse of inflammation. The mean time observed of treatment was 17.3 ± 11.9 months (range 3–41.5 months). Visual acuity of 20/20 was achieved by 38% of the eyes in the corticosteroid group and by 74% in the corticosteroid + MMF group (p < 0.001). Recurrent inflammation of ≥3 times was reduced significantly (p = 0.0383) in the corticosteroid + MMF group (3%) as compared to corticosteroid group (18%). Development of all complications was significantly higher in the corticosteroid group (43%) compared with the corticosteroid + MMF group (8%) (p < 0.001). None of the eyes in the corticosteroid + MMF group developed ‘sunset glow fundus’. Conclusions: Addition of MMF as first‐line therapy to corticosteroids in patients with acute uveitis associated with VKH disease leads to significant reduction in recurrences of uveitis and development of late complications and significantly improves visual outcome. 相似文献