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101.
O'Malley CJ; Rasko JE; Basser RL; McGrath KM; Cebon J; Grigg AP; Hopkins W; Cohen B; O'Byrne J; Green MD; Fox RM; Berndt MC; Begley CG 《Blood》1996,88(9):3288-3298
This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status. 相似文献
102.
Sharmistha Dev MD MPH Andrew A. Gonzalez MD JD MPH Jessica Coffing MPH James E. Slaven MS Shantanu Dev BS Stan Taylor MA Carrie Ballard S. Nicole Hastings MD MHSc Dawn M. Bravata MD 《Academic emergency medicine》2023,30(4):349-358
Objectives
Frailty is a clinical syndrome characterized by decreased physiologic reserve that diminishes the ability to respond to stressors such as acute illness. Veterans Health Administration (VA) emergency departments (ED) are the primary venue of care for Veterans with acute illness and represent key sites for frailty recognition. As questionnaire-based frailty instruments can be cumbersome to implement in the ED, we examined two administratively derived frailty scores for use among VA ED patients.Methods
This national retrospective cohort study included all VA ED visits (2017–2020). We evaluated two administratively derived scores: the Care Assessment Needs (CAN) score and the VA Frailty Index (VA-FI). We categorized all ED visits across four frailty groups and examined associations with outcomes of 30-day and 90-day hospitalization and 30-day, 90-day, and 1-year mortality. We used logistic regression to assess the model performance of the CAN score and the VA-FI.Results
The cohort included 9,213,571 ED visits. With the CAN score, 28.7% of the cohort were classified as severely frail; by VA-FI, 13.2% were severely frail. All outcome rates increased with progressive frailty (p-values for all comparisons < 0.001). For example, for 1-year mortality based on the CAN score frailty was determined as: robust, 1.4%; prefrail, 3.4%; moderately frail, 7.0%; and severely frail, 20.2%. Similarly, for 90-day hospitalization based on VA-FI, frailty was determined as prefrail, 8.3%; mildly frail, 15.3%; moderately frail, 29.5%; and severely frail, 55.4%. The c-statistics for CAN score models were higher than for VA-FI models across all outcomes (e.g., 1-year mortality, 0.721 vs. 0.659).Conclusions
Frailty was common among VA ED patients. Increased frailty, whether measured by CAN score or VA-FI, was strongly associated with hospitalization and mortality and both can be used in the ED to identify Veterans at high risk for adverse outcomes. Having an effective automatic score in VA EDs to identify frail Veterans may allow for better targeting of scarce resources. 相似文献103.
Kin Y. Mok Emma L. Jones Marisa Hanney Denise Harold Rebecca Sims Julie Williams Clive Ballard John Hardy 《Neurobiology of aging》2014
It is known that Alzheimer's disease (AD) presents at an early age in people with Down syndrome (DS). The trisomy 21 in DS provides an opportunity to study the effect of duplicated genes in AD. APP and BACE2 are 2 genes located in chromosome 21 and related to AD. We looked into our cohort of 67 DS cases with dementia for the effect of BACE2 variants in age of onset of dementia. Of the 83 single-nucleotide polymorphisms (SNPs), 6 were associated with age of onset and another 8 SNPs were borderline associated. Our finding also replicated a previous study showing association of rs2252576 with AD. 相似文献
104.
Agustín Ruiz Isabel Hernández Maiteé Ronsende-Roca Antonio González-Pérez Emma Rodriguez-Noriega Reposo Ramírez-Lorca Ana Mauleón Concha Moreno-Rey Lucie Boswell Larry Tune Sergi Valero Montserrat Alegret Javier Gayán James T. Becker Luis Miguel Real Lluís Tárraga Clive Ballard Michael Terrin Stephanie Sherman Haydeh Payami Oscar L. López Jacobo E. Mintzer Mercè Boada 《Neurobiology of aging》2014
105.
Jenessa N Johnston Darcy Campbell Hector J Caruncho Ioline D Henter Elizabeth D Ballard Carlos A Zarate Jr 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2022,25(3):197
BackgroundSuicide is a global health crisis. However, no objective biomarkers of suicide risk currently exist, and self-reported data can be unreliable, which limits prediction, diagnostic, and treatment efforts. Reliable biomarkers that can differentiate between diagnostic subgroups, predict worsening symptoms, or suggest novel therapeutic targets would be extremely valuable for patients, researchers, and clinicians.MethodsMEDLINE was searched for reports published between 2016 and 2021 using search terms (suicid*) AND (biomarker*) OR (indicat*). Reports that compared biomarkers between suicidal ideation, suicide attempt, death from suicide, or any suicide subgroup against other neuropsychiatric disorders were included. Studies exclusively comparing suicidal behavior or death from suicide with healthy controls were not included to ensure that biomarkers were specific to suicide and not other psychopathology.ResultsThis review summarizes the last 5 years of research into suicide-associated biomarkers and provides a comprehensive guide for promising and novel biomarkers that encompass varying presentations of suicidal ideation, suicide attempt, and death by suicide. The serotonergic system, inflammation, hypothalamic-pituitary-adrenal axis, lipids, and endocannabinoids emerged as the most promising diagnostic, predictive, and therapeutic indicators.ConclusionsThe utility of diagnostic and predictive biomarkers is evident, particularly for suicide prevention. While larger-scale studies and further in-depth research are required, the last 5 years of research has uncovered essential biomarkers that could ultimately improve predictive strategies, aid diagnostics, and help develop future therapeutic targets. 相似文献
106.
This study of wound repair in the aged rat is based on increased carbohydrate content of various proteins which occurs with aging and is readily seen in the microvasculature (MV). We have used the periodic acid-Schiff (PAS) reaction to identify histochemically the carbohydrate moiety of the glycoproteins found in these blood vessels. In the young rat, as in other young vertebrates, elements of the MV are PAS negative and become increasingly PAS+ beyond the half life span. During acute wound repair in an old animal, the new capillaries and venules are PAS- 2 weeks after injury, moderately PAS+ at 4 weeks, and intensely PAS+ at 8 weeks. Arterioles are present and PAS+ at 6 weeks, and intensively positive at 8 weeks, comparable to vessels remote from the wound site. The MV in wound repair in a young animal remains PAS- throughout healing. Rapid aging of the microvasculature in wound repair in an old animal reproduces histochemically the aging which occurs progressively during the prior 24 months. These histochemical changes may result from successive enzymatic and nonenzymatic glycosylation of the various basement membrane proteins in the microvasculature in both normal aging and wound repair in the aged animal. The latter may serve as a model for study of accelerated aging. 相似文献
107.
Incisional endometriomas after Cesarean section: a case series 总被引:1,自引:0,他引:1
OBJECTIVE: To review a series of women with endometriomas developing in the scar of the skin incision performed for cesarean section. STUDY DESIGN: A total of 37 patients diagnosed with incisional endometrioma at the time of surgical excision from 1975 to 2005 were identified from the comprehensive surgical database, which includes all operative procedures performed at this institution. The medical records of 33 of the 37 patients were available for review. RESULTS: The endometriomas ranged in size from a diameter of 1-12 cm and were initially observed to be present 6 months to 9 years (mean, 3.2) after the surgical procedure. Diagnosis was best made by needle aspiration of chocolate colored fluid from the mass. Medical therapy with a gonadotropin releasing hormone agonist, medroxyprogesterone acetate or combination oral contraceptives had been attempted in 14 patients without a change in lesion size. All patients were cured by surgical excision of the endometrioma. CONCLUSION: The overall incidence of incisional endometriomas following cesarean section during the 30-year period was 0.08%. Optimal treatment is by surgical excision. It is hypothesized that failure to close the parietal and visceral peritoneum with sutures at the time of cesarean section may markedly increase the postoperative occurrence of an endometrioma in the skin incision scar. 相似文献
108.
Arianne C Lim Kitty WM Bloemenkamp Kees Boer Johannes J Duvekot Jan Jaap HM Erwich Tom HM Hasaart Pieter Hummel Ben WJ Mol Jos PM Offermans Charlotte M van Oirschot Job G Santema Hubertina CJ Scheepers Willem A Schöls Frank PHA Vandenbussche Maurice GAJ Wouters Hein W Bruinse 《BMC pregnancy and childbirth》2007,7(1):1-6
Background
Adequate vitamin D concentrations during pregnancy are necessary to neonatal calcium homeostasis, bone maturation and mineralization. The aim of study is to evaluate serum vitamin D concentrations in mothers and their newborns and effect of vitamin D deficiency on pregnancy outcomes.Methods
552 pregnant women were recruited from Tehran University educating hospitals in the winter of 2002. Maternal and cord blood samples were taken at delivery. The serum was assayed for 25-hydroxyvitamin D3, calcium, phosphorus and parathyroid hormone.Results
The prevalence of vitamin D deficiency in maternal and cord blood samples were 66.8% and 93.3%, respectively (<35 nmol/l). There was significant correlation between maternal and cord blood serum concentrations of vitamin D. In mothers with vitamin D deficiency, cord blood vitamin D concentrations was lower than those from normal mothers (P = .001). Also, a significant direct correlation was seen between maternal vitamin D intake and weight gain during pregnancy.Conclusion
Consideration to adequate calcium and vitamin D intake during pregnancy is essential. Furthermore, we think it is necessary to reconsider the recommendation for vitamin D supplementation for women during pregnancy. 相似文献109.
C. G. Ballard S. Handy L. McGibben R. N. C. Mohan W. R. Silveira 《The International journal of eating disorders》1993,13(2):245-248
Accurate data are not available for the prevalence of eating disorders amongst the Asian population in Britain. Only a handful of cases have been reported in the literature [Bhadrinath (1990). British Journal of Psychiatry, 156, 565–568.] suggested that it is an uncommon phenomenon despite Dolan's recent finding [Dolan, Lacey, & Evans (1990). British Journal of Psychiatry, 157, 523–528.] that there were elevated Eating Attitudes Test (EAT) scores in a sample of young Asian adults compared with Caucasians. We report a case of an Asian girl with a rare inborn error of metabolism and an eating disorder. © 1993 by John Wiley & Sons, Inc. 相似文献
110.
Tessa Timmers Rik Ossenkoppele Denise Visser Hayel Tuncel Emma E Wolters Sander CJ Verfaillie Wiesje M van der Flier Ronald Boellaard Sandeep SV Golla Bart NM van Berckel 《Journal of cerebral blood flow and metabolism》2020,40(12):2464
The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [18F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [18F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr80–100 and SUVr110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods. 相似文献