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41.
HFE p.C282Y homozygosity predisposes to rapid serum ferritin rise after menopause: A genotype‐stratified cohort study of hemochromatosis in Australian women
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42.
José I. López Rafael Pulido Jesús M. Cortés Javier C. Angulo Charles H. Lawrie 《Pathology, research and practice》2018,214(8):1110-1114
Intratumor heterogeneity (ITH) detection remains a challenge in modern oncology because it can have a direct impact on the success of new therapies. Anti-PD-1/PD-L1 immunotherapy is an emerging treatment modality that is showing great promise for clear cell renal cell carcinoma (CCRCC) patients with advanced disease. Patient selection for such therapy relies upon the immunohistochemical detection of PD-1/PD-L1, however the degree of ITH for these markers among tumor cells and/or inflammatory mononuclear infiltrates remains unknown. Therefore, we analyzed PD-L1 (SP-142) expression in the tumor inflammatory cells of 22 CCRCC cases with the aim to define the pattern of PD-L1 expression, and to compare the reliability of current tumor sampling protocols (RS) with a multisite tumor sampling strategy (MSTS). While the RS protocol identified 5/22 (22.7%) of cases that were positive for PD-L1 expression, MSTS identified 10/22 (45.45%) of cases. This suggests that RS may miss a proportion of CCRCC patients that might benefit from immunotherapy. In addition, MSTS demonstrated that positive and negative regions of PD-L1 expression are very variable within each tumor. 相似文献
43.
Human burst-forming units-erythroid need direct interaction with stem cell factor for further development 总被引:6,自引:3,他引:6
To understand the factors that regulate the early growth and development of immature erythroid progenitor cells, the burst-forming units-erythroid (BFU-E), it is necessary to have both highly purified target cells and a medium free of serum. When highly purified human blood BFU-E were cultured in a serum-free medium adequate for the growth of later erythroid progenitors, BFU-E would not grow even with the addition of recombinant human interleukin-3 (rIL-3), known to be essential for these cells. However, the addition of recombinant human stem cell factor (rSCF), which supports germ cell and pluripotential stem cell growth, stimulated BFU-E to grow equally well in serum-free as in serum-containing medium. Limiting dilution studies showed that rSCF acts directly on the BFU-E that do not require accessory cells for growth. Furthermore, rSCF was necessary for BFU-E development during the initial 7 days of culture, until these cells reached the stage of the late progenitors, the colony-forming units-erythroid (CFU-E). These studies indicate that early erythropoiesis is dependent on the direct action of SCF that not only affects early stem cells but is continually necessary for the further development of committed erythroid progenitor cells until the CFU-E stage of maturation. 相似文献
44.
45.
K. Carlos El-Tallawi Peng Zhang Robert Azencott Jiwen He Elizabeth L. Herrera Jiaqiong Xu Mohammed Chamsi-Pasha Jessen Jacob Gerald M. Lawrie William A. Zoghbi 《JACC: Cardiovascular Imaging》2021,14(6):1099-1109
ObjectivesThe aim of this study was to quantitate patient-specific mitral valve (MV) strain in normal valves and in patients with mitral valve prolapse with and without significant mitral regurgitation (MR) and assess the determinants of MV strain.BackgroundFew data exist on MV deformation during systole in humans. Three-dimensional echocardiography allows for dynamic MV imaging, enabling digital modeling of MV function in health and disease.MethodsThree-dimensional transesophageal echocardiography was performed in 82 patients, 32 with normal MV and 50 with mitral valve prolapse (MVP): 12 with mild mitral regurgitation or less (MVP ? MR) and 38 with moderate MR or greater (MVP + MR). Three-dimensional MV models were generated, and the peak systolic strain of MV leaflets was computed on proprietary software.ResultsLeft ventricular ejection fraction was normal in all groups. MV annular dimensions were largest in MVP + MR (annular area: 13.8 ± 0.7 cm2) and comparable in MVP ? MR (10.6 ± 1 cm2) and normal valves (10.5 ± 0.3 cm2; analysis of variance: p < 0.001). Similarly, MV leaflet areas were largest in MVP + MR, particularly the posterior leaflet (8.7 ± 0.5 cm2); intermediate in MVP ? MR (6.5 ± 0.7 cm2); and smallest in normal valves (5.5 ± 0.2 cm2; p < 0.0001). Strain was overall highest in MVP + MR and lowest in normal valves. Patients with MVP ? MR had intermediate strain values that were higher than normal valves in the posterior leaflet (p = 0.001). On multivariable analysis, after adjustment for clinical and MV geometric parameters, leaflet thickness was the only parameter that was retained as being significantly correlated with mean MV strain (r = 0.34; p = 0.008).ConclusionsMVs that exhibit prolapse have higher strain compared to normal valves, particularly in the posterior leaflet. Although higher strain is observed with worsening MR and larger valves and annuli, mitral valve leaflet thickness—and, thus, underlying MV pathology—is the most significant independent determinant of valve deformation. Future studies are needed to assess the impact of MV strain determination on clinical outcome. 相似文献
46.
A 13 month old child with classic features of absent pulmonary valve with tetralogy of Fallot underwent successful surgical repair by closure of the ventricular septal defect, relief of the right ventricular outflow tract obstruction, and partial resection and plastic repair of the aneurysmally dilated pulmonary arteries. Cardiac catheterisation data and clinical follow up for more than 18 months after the operation indicated excellent results. It is suggested that plastic repair of the aneurysmally dilated pulmonary arteries along with closure of the ventricular septal defect and relief of the right ventricular outflow tract obstruction should be performed early, perhaps between 1 and 2 years of age. 相似文献
47.
48.
Ni Sann Khin Sze Huey Tan Michael LC Wang Tian Rui Siow Faye LWT Lim Fu Qiang Wang Matthew CH Ng Justina YC Lam Connie Yip 《The British journal of radiology》2021,94(1122)
Objective:Chemoradiation (CRT) may induce a change in systemic inflammatory state which could affect clinical outcomes in oesophageal cancer. We aimed to evaluate the changes and prognostic significance of systemic inflammatory markers following definitive CRT in oesophageal squamous cell carcinoma.Methods:A total of 53 patients treated with concurrent CRT were included in this retrospective analysis. We compared neutrophils, lymphocytes, platelets, neutrophil–lymphocyte ratio (NLR) and platelet–lymphocyte ratio (PLR) before and after CRT using Wilcoxon signed-rank test. Overall survival (OS) and progression-free survival (PFS) were calculated. Univariable and multivariable survival analysis were performed using Cox regression analysis. Clinical univariable survival prognostic factors with p < 0.1 were included in a multivariable cox regression analysis for backward stepwise model selection.Results:Both NLR (median ∆+2.8 [IQR −0.11, 8.62], p < 001) and PLR (median ∆+227 [81.3–523.5], p < 0.001) increased significantly after CRT. Higher levels of pre-CRT, post-CRT and change (∆) in NLR and PLR were associated with inferior OS and PFS. Post-CRT NLR (HR 1.04, 95% CI 1.02–1.07, p < 0.001), post-CRT platelets (HR 1.03, 95% CI 1.01–1.05, p = 0.005), cT-stage (HR 3.83, 95% CI 1.39–10.60, p = 0.01) and RT dose (HR 0.41, 95% CI 0.21–0.81, p = 0.01) were independent prognostic factors for OS in multivariable analysis. Change in NLR (HR 1.04, 95% CI 1.01–1.06, p = 0.001), post-CRT platelets (HR 1.03, 95% CI 1.01–1.05, p = 0.002), cT-stage (HR 3.98, 95% CI 1.55–10.25, p = 0.004) and RT dose (HR 0.41, 95% CI 0.21–0.80, p = 0.009) were independent prognostic factors for PFS.Conclusion:Both NLR and PLR increased following definitive CRT. Post-CRT NLR and ∆NLR were associated with adverse survival in oesophageal SCC.Advances in knowledge:We showed that CRT increased PLR and NLR, possibly reflecting a systemic inflammatory state which were associated with poor clinical outcomes in oesophageal SCC. 相似文献
49.
Christen Lawrie Martha E.F. Highfield Sherri Mendelson 《Nursing for Women's Health》2021,25(3):170-178
ObjectiveTo facilitate optimal hospital experiences and breastfeeding clinical outcomes among women by reducing interruptions during their first 24 hours in the postpartum period.DesignEvidence-based practice change initiated by a registered nurse staff member.Setting/Local ProblemThere was concern that numerous visitor and staff interruptions to women during their early postpartum hours were interfering with establishing breastfeeding and maintaining a restful environment on our 21-bed postpartum unit within a 377-bed, Magnet-recognized, religiously affiliated hospital in suburban southern California.ParticipantsMedically stable women with uncomplicated childbirth during the previous 24 hours and women in the postpartum period whose responses were recorded in facility databases maintained by the departments of Lactation Services and Nursing Research.Intervention/MeasurementsA daily quiet time from 1:00 p.m. to 3:00 p.m. was instituted on the postpartum unit. Measurements before and after implementing quiet time included data on (a) interruptions, as the number of times someone opened or entered women’s room doors; (b) exclusive breastfeeding rates; and (c) women’s postdischarge reports of their hospital experiences.ResultsAfter quiet time was implemented, interruptions fell from an average of 74 to an average of 37 per day (n = 21, p = .02), and the percentage of women breastfeeding rose from 34% to 48% (n = 193, p = .39). Women’s ratings of unit quietness improved significantly (n = 169, p = .008) to above the benchmark, and their overall facility rating and willingness to recommend the facility remained above the benchmark on surveys from the Hospital Consumer Assessment of Healthcare Providers and Systems.ConclusionA daily afternoon quiet time for women hospitalized in the postpartum period may reduce interruptions to women and thereby potentially increase breastfeeding rates and improve women’s perceptions of their hospital experiences. Unsolicited reports from staff suggested that quiet time was well received by nurses providing postpartum care. 相似文献
50.
Effects of Deletion of ERα in Osteoblast‐Lineage Cells on Bone Mass and Adaptation to Mechanical Loading Differ in Female and Male Mice
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Katherine M Melville Natalie H Kelly Gina Surita Daniel B Buchalter John C Schimenti Russell P Main F Patrick Ross Marjolein CH van der Meulen 《Journal of bone and mineral research》2015,30(8):1468-1480
Estrogen receptor alpha (ERα) has been implicated in bone's response to mechanical loading in both males and females. ERα in osteoblast lineage cells is important for determining bone mass, but results depend on animal sex and the cellular stage at which ERα is deleted. We demonstrated previously that when ERα is deleted from mature osteoblasts and osteocytes in mixed‐background female mice, bone mass and strength are decreased. However, few studies exist examining the skeletal response to loading in bone cell–specific ERαKO mice. Therefore, we crossed ERα floxed (ERαfl/fl) and osteocalcin‐Cre (OC‐Cre) mice to generate animals lacking ERα in mature osteoblasts and osteocytes (pOC‐ERαKO) and littermate controls (LC). At 10 weeks of age, the left tibia was loaded in vivo for 2 weeks. We analyzed bone mass through micro‐CT, bone formation rate by dynamic histomorphometry, bone strength from mechanical testing, and osteoblast and osteoclast activity by serum chemistry and immunohistochemistry. ERα in mature osteoblasts differentially regulated bone mass in males and females. Compared with LC, female pOC‐ERαKO mice had decreased cortical and cancellous bone mass, whereas male pOC‐ERαKO mice had equal or greater bone mass than LC. Bone mass results correlated with decreased compressive strength in pOC‐ERαKO female L5 vertebrae and with increased maximum moment in pOC‐ERαKO male femora. Female pOC‐ERαKO mice responded more to mechanical loading, whereas the response of pOC‐ERαKO male animals was similar to their littermate controls. © 2015 American Society for Bone and Mineral Research. © 2015 American Society for Bone and Mineral Research. 相似文献