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Background: Different patient characteristics influence the decision to order diagnostic imaging for deep venous thrombosis (DVT) and pulmonary embolism (PE) in different settings (emergency department (ED), hospital, and office). Diagnostic yield is defined as the proportion of tests that report positive results. We hypothesize different patient characteristics are associated with higher or lower diagnostic yield of imaging for DVT and PE in different settings., Methods: We used Optum Clinformatics™ national claims database (2015-2019) to assess the diagnostic yield of imaging for DVT and PE in three settings: (a) ED discharge, (b) Hospitalized, and (c) Office. We studied the patient characteristics associated with diagnostic yield using logistic regression., Results: Diagnostic imaging for DVT and PE was performed in 1,502,417 and 710,263 visits, respectively. Diagnostic yield for DVT and PE was 9.8 ± 0.1 % and 12.7 ± 0.1 %, respectively in the overall cohort. In the ED discharge, hospitalized, and office settings, diagnostic yield for DVT was 10.4 ± 0.1 %, 16.9 ± 0.1 %, and 6.5 ± 0.1 %, respectively, and that for PE 6.4 ± 0.1 %, 18.7 ± 0.1 %, and 8.8 ± 0.2 %, respectively. Of the patients who underwent imaging for DVT, higher diagnostic yield was more likely with thrombophilia, central venous access, and cancer. Of the patients who underwent imaging for PE, higher diagnostic yield was most likely with thrombophilia, respiratory failure, and heart failure or acute myocardial infarction., Conclusions: In each setting, different patient characteristics influence the diagnostic yield of imaging for DVT and PE and can inform clinical practice. Judicious use of imaging for DVT and PE could reduce costs and avoid exposure to radiation and contrast., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background Oral anticoagulation reduces stroke and disability in atrial fibrillation (AF) but is underused. We evaluated the effects of a novel patient-clinician shared decision-making (SDM) tool in reducing oral anticoagulation patient's decisional conflict as compared with usual care. Methods and Results We designed and evaluated a new digital decision aid in a multicenter, randomized, comparative effectiveness trial, ENHANCE-AF (Engaging Patients to Help Achieve Increased Patient Choice and Engagement for AF Stroke Prevention). The digital AF shared decision-making toolkit was developed using patient-centered design with clear health communication principles (eg, meaningful images, limited text). Available in English and Spanish, the toolkit included the following: (1) a brief animated video; (2) interactive questions with answers; (3) a quiz to check on understanding; (4) a worksheet to be used by the patient during the encounter; and (5) an online guide for clinicians. The study population included English or Spanish speakers with nonvalvular AF and a CHA 2 DS 2 -VASc stroke score ≥1 for men or ≥2 for women. Participants were randomized in a 1:1 ratio to either usual care or the shared decision-making toolkit. The primary end point was the validated 16-item Decision Conflict Scale at 1 month. Secondary outcomes included Decision Conflict Scale at 6 months and the 10-item Decision Regret Scale at 1 and 6 months as well as a weighted average of Mann-Whitney U -statistics for both the Decision Conflict Scale and the Decision Regret Scale. A total of 1001 participants were enrolled and followed at 5 different sites in the United States between December 18, 2019, and August 17, 2022. The mean patient age was 69±10 years (40% women, 16.9% Black, 4.5% Hispanic, 3.6% Asian), and 50% of participants had CHA 2 DS 2 -VASc scores ≥3 (men) or ≥4 (women). The primary end point at 1 month showed a clinically meaningful reduction in decisional conflict: a 7-point difference in median scores between the 2 arms (16.4 versus 9.4; Mann-Whitney U -statistics=0.550; P =0.007). For the secondary end point of 1-month Decision Regret Scale, the difference in median scores between arms was 5 points in the direction of less decisional regret ( P =0.078). The treatment effects lessened over time: at 6 months the difference in medians was 4.7 points for Decision Conflict Scale ( P =0.060) and 0 points for Decision Regret Scale ( P =0.35). Conclusions Implementation of a novel shared decision-making toolkit (afibguide.com; afibguide.com/clinician) achieved significantly lower decisional conflict compared with usual care in patients with AF. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04096781.

Purpose of Review: Anemia in pregnancy is associated with increased maternal and neonatal morbidity. There is increasing awareness amongst obstetricians about the need to screen for iron deficiency anemia (IDA), as well as growing literature on diagnosis and treatment. This review aims to summarize causes, consequences, treatment, and evaluation of IDA in pregnancy., Recent Findings: National guidelines provide varying guidance on diagnosis and treatment of IDA in pregnancy. Serum ferritin is a helpful adjunct for the diagnosis of IDA. Oral iron remains an option for treatment; absorption is improved with every other day dosing and is effective for patients able to tolerate. Emerging studies on modern generations of intravenous (IV) iron demonstrate shorter infusion times and improved safety profiles. Notably, recent UK guidelines provide consideration for universal IV iron supplementation for treatment of anemia beyond 34 weeks of pregnancy., Summary: Iron, in dietary, oral, and IV forms, has been found effective in resolving anemia in pregnancy. Pregnant people with IDA in the third trimester are more likely to benefit from IV iron. Future studies designed and powered to assess maternal and perinatal morbidity indicators and blood transfusion rates can strengthen recommendations., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction: Venous thromboembolism (VTE) management increasingly involves anticoagulation with direct oral anticoagulants (DOACs). Few studies have used competing-risks analyses to ascertain the mortality-adjusted hemorrhage and recurrent VTE (rVTE) risk of individual DOACs. Furthermore, hemorrhage risk factors in patients treated with apixaban remain underexplored., Materials and Methods: Patients diagnosed with VTE receiving anticoagulation were identified from the Optum Clinformatics Data Mart (2003-2019). Study endpoints included readmissions for intracranial hemorrhage (ICH), non-intracranial hemorrhage (non-ICH hemorrhage), and rVTE. Coarsened exact matching was used to balance baseline clinical characteristics. Complication incidence was evaluated using a competing-risks framework. We additionally modeled hemorrhage risk in apixaban-treated patients., Results: Overall, 225,559 patients were included, of whom 34,201 received apixaban and 46,007 received rivaroxaban. Compared to rivaroxaban, apixaban was associated with decreased non-ICH hemorrhage (sHR = 0.560, 95%CI = 0.423-0.741), but not ICH, and rVTE (sHR = 0.802, 95%CI = 0.651-0.988) risk. This was primarily in emergent readmissions (sHR[emergent hemorrhage] = 0.515, 95%CI = 0.372-0.711; sHR[emergent rVTE] = 0.636, 95%CI = 0.488-0.830). Contributors to emergent hemorrhage in apixaban-treated patients include older age (sHR = 1.025, 95%CI = 1.011-1.039), female sex (sHR = 1.662, 95%CI = 1.252-2.207), prior prescription antiplatelet therapy (sHR = 1.591, 95%CI = 1.130-2.241), and complicated hypertension (sHR = 1.936, 95%CI = 1.134-3.307). Patients anticipated to be "high-risk" experienced elevated ICH (sHR = 3.396, 95%CI = 1.375-8.388) and non-ICH hemorrhage (sHR = 3.683, 95%CI = 2.957-4.588) incidence., Conclusions: In patients with VTE receiving anticoagulation, apixaban was associated with reduced non-ICH hemorrhage and rVTE risk, compared to rivaroxaban. Risk reduction was restricted to emergent readmissions. We present a risk-stratification approach to predict hemorrhage in patients receiving apixaban, potentially guiding future clinical decision-making., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Thrombophilia testing is frequently ordered in the inpatient setting despite its limited impact on clinical decision-making and unreliable results in the setting of acute thrombosis or ongoing anticoagulation. We sought to determine the effect of an educational intervention in reducing inappropriate thrombophilia testing for hospitalized patients., Methods: During the 2014 academic year, we implemented an educational intervention with a phase implementation design for Internal Medicine interns at Stanford University Hospital. The educational session covering epidemiology, appropriate thrombophilia evaluation and clinical rationale behind these recommendations. Their ordering behavior was compared with a contemporaneous control (non-medicine and private services) and a historical control (interns from prior academic year). From the analyzed data, we determined the proportion of inappropriate thrombophilia testing of each group. Logistic generalized estimating equations were used to estimate odds ratios for inappropriate thrombophilia testing associated with the intervention., Results: Of 2151 orders included, 934 were deemed inappropriate (43.4%). The two intervention groups placed 147 orders. A pooled analysis of ordering practices by intervention groups revealed a trend toward reduction of inappropriate ordering (p = 0.053). By the end of the study, the intervention groups had significantly lower rates of inappropriate testing compared to historical or contemporaneous controls., Conclusion: A brief educational intervention was associated with a trend toward reduction in inappropriate thrombophilia testing. These findings suggest that focused education on thrombophilia testing can positively impact inpatient ordering practices.

This phase 1 study investigated the safety of the anthracycline amrubicin combined with lenalidomide and dexamethasone in adults with relapsed or refractory multiple myeloma. A standard 3 + 3 design was used. Patients received intravenous amrubicin 40-80 mg/m 2 on day one, lenalidomide 15 mg orally on days 1-14, and dexamethasone 40 mg orally weekly on 21 day cycles. 14 patients were enrolled, and completed a median of three cycles. The maximum tolerated dose was not reached. One patient experienced dose limiting toxicity of dizziness and diarrhea. The most frequent non-hematologic toxicity was infection (79%). Serious adverse events included cord compression and sepsis. Three patients (21%) had a partial response or better, and seven (50%) had stable disease. The median duration of response was 4.4 months, and the median progression-free survival was 3 months. Amrubicin combined with lenalidomide and dexamethasone, was safe and demonstrated clinical activity in relapsed or refractory multiple myeloma.Clinicaltrials.gov identifier: NCT01355705.

Chemerin is a chemoattractant and adipokine that circulates in blood as inactive prochemerin (chem163S). Chem163S is activated by a series of C-terminal proteolytic cleavages resulting in diverse chemerin forms with different levels of activity. We screened a panel of proteases in the coagulation, fibrinolytic, and inflammatory cascades to identify those that process prochemerin in plasma. Factor XIa (FXIa) cleaved chem163S, generating a novel chemerin form, chem162R, as an intermediate product, and chem158K, as the final product. Processing at Arg 162 was not required for cleavage at Lys 158 or regulation of chemerin bioactivity. Contact phase activation of human platelet-poor plasma by kaolin led to cleavage of chem163S, which was undetectable in FXI-depleted plasma and markedly enhanced in platelet-rich plasma (PRP). Contact phase activation by polyphosphate in PRP resulted in 75% cleavage of chem163S. This cleavage was partially inhibited by hirudin, which blocks thrombin activation of FXI. After activation of plasma, levels of the most potent form of chemerin, chem157S, as well as inactive chem155A, increased. Plasma levels of chem163S in FXI-deficient patients were significantly higher compared with a matched control group (91 ± 10 ng/mL vs 58 ± 3 ng/mL, n = 8; P < .01) and inversely correlated with the plasma FXI levels. Thus FXIa, generated on contact phase activation, cleaves chem163S to generate chem158K, which can be further processed to the most active chemerin form, providing a molecular link between coagulation and inflammation.

Laboratory costs of thrombophilia testing exceed an estimated $650 million (in US dollars) annually. Quantifying the prevalence and financial impact of potentially inappropriate testing in the inpatient hospital setting represents an integral component of the effort to reduce healthcare expenditures. We conducted a retrospective analysis of our electronic medical record to evaluate 2 years' worth of inpatient thrombophilia testing measured against preformulated appropriateness criteria. Cost data were obtained from the Centers for Medicare and Medicaid Services 2016 Clinical Laboratory Fee Schedule. Of the 1817 orders analyzed, 777 (42.7%) were potentially inappropriate, with an associated cost of $40,422. The tests most frequently inappropriately ordered were Factor V Leiden, prothrombin gene mutation, protein C and S activity levels, antithrombin activity levels, and the lupus anticoagulant. Potentially inappropriate thrombophilia testing is common and costly. These data demonstrate a need for institution-wide changes in order to reduce unnecessary expenditures and improve patient care., (© 2017 Society of Hospital Medicine.)

Pralatrexate inhibits folic acid metabolism, and preclinical studies have shown that it is cytotoxic to multiple myeloma cells. This phase 1 study investigated the safety and efficacy of pralatrexate in combination with bortezomib in adults with relapsed or refractory multiple myeloma. A standard 3 + 3 design was used. Patients received intravenous pralatrexate at doses ranging from 10 to 30 mg/m(2) and intravenous bortezomib at a dose of 1·3 mg/m(2) on days 1, 8 and 15 of each 4-week cycle. Eleven patients were enrolled and completed a median of two cycles. The maximum tolerated dose was 20 mg/m(2) . Two patients experienced dose-limiting toxicity of mucositis. The most frequent non-haematological toxicities were fatigue (55%) and mucositis (45%). There were three serious adverse events in three patients: rash, sepsis and hypotension. One patient (9%) had a very good partial response, 1 (9%) had a partial response, 1 (9%) had minimal response and two (18%) had progressive disease. The median duration of response was 4 months, the median time to next treatment was 3·4 months and the median time to progression was 4 months. Pralatrexate, in combination with bortezomib, was generally safe and demonstrated modest activity in relapsed or refractory multiple myeloma. Clinicaltrials.gov identifier: NCT01114282., (© 2016 John Wiley & Sons Ltd.)

The outcome of sequential azacitidine with lenalidomide has not been reported in previously treated patients with acute myeloid leukemia (AML) and higher risk myelodysplastic syndrome (MDS). This study describes a phase 2 study evaluating the safety and efficacy of this combination in elderly patients with AML and MDS with prior hypomethylating agent (HMA) and/or immunomodulatory agent exposure. Patients were treated on a 42-day cycle with azacitidine at 75 mg/m2 SQ/IV daily on days 1-7, followed by lenalidomide 50 mg orally daily on days 8-28. The median number of treatment cycles on study was two (range = 1-11). Of 32 evaluable patients, the overall response rate was 25%. Neutropenic fever was the most common serious adverse event, but overall the combination was well-tolerated. The median overall survival (OS) for responders vs non-responders was 9.8 vs 4.0 months, respectively (HR = 0.36, p = 0.016). In conclusion, this combination demonstrated modest clinical activity in this poor risk population.

Catastrophic antiphospholipid syndrome (CAPS) is fatal in approximately 44% of patients in whom the diagnosis is made, thus demonstrating the inadequacy of current medical therapy. In this report, we discuss a 47-year-old man with a known history of primary antiphospholipid syndrome, who presented with CAPS after undergoing cholecystectomy and a treatment-refractory early relapse after development of colitis. Given the potential therapeutic efficacy of complement inhibition in antiphospholipid syndrome, the patient was administered eculizumab, a terminal complement inhibitor. Progressive clinical improvement and laboratory improvement were observed upon initiation of eculizumab. He has remained in remission for over 16 months of follow-up while on eculizumab. In conclusion, this case represents successful use of eculizumab for the treatment of primary CAPS.

The survival of patients with relapsed or refractory acute lymphoblastic leukemia (ALL) is poor. We performed a retrospective analysis of 40 patients treated with five days of mitoxantrone 8mg/m(2)/day, etoposide 100mg/m(2)/day, and cytarabine 1000mg/m(2)/day (MEC). The complete remission rate was 30% and median remission duration was 11.2 months. Median overall survival was 6.5 months. In univariate analysis, patients in first relapse had improved overall survival compared to ≥second relapse (p=0.02). Thirty-day mortality rate was 7.5%. In relapsed or refractory ALL, MEC demonstrated moderate activity, but did not improve survival compared to published salvage chemotherapy regimens., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

There are limited treatment options for older patients with acute myeloid leukemia and prognosis of these patients remains poor, thereby warranting development of novel therapies. We evaluated the efficacy and safety of azacitidine in combination with lenalidomide as front-line therapy for older patients with acute myeloid leukemia. Patients ≥ 60 years of age with untreated acute myeloid leukemia received azacitidine 75 mg/m2 for 7 days followed by escalating doses of lenalidomide daily for 21 days starting on day 8 of each cycle every 6 weeks. Patients received continued therapy until disease progression, unacceptable toxicity, or completion of 12 cycles. Forty-two patients (median age, 74 years) were enrolled with equal distribution according to European LeukemiaNet risk. The overall response rate was 40% (rate of complete remission with or without complete recovery of blood counts = 28%). The median time to complete remission with or without complete recovery of blood counts was 12 weeks, and duration of this status was 28 weeks (range, 4 - >104 weeks). Therapy-related acute myeloid leukemia and a high score on the Hematopoietic Cell Transplantation Comorbidity Index were negative predictors of response. Early death was noted in 17% of patients. Grades ≥ 3 toxicities were uncommon and most adverse events were gastrointestinal, fatigue and myelosuppression. In conclusion, a sequential combination of azacitidine plus lenalidomide has clinical activity in older patients with acute myeloid leukemia, and further studies of this combination are underway.

Background: This phase I trial was conducted to determine the safety and pharmacokinetics of monoclonal antibody 216, a human monoclonal Immunoglobulin M antibody targeting a linear B-cell lactosamine antigen, administered alone and in combination with vincristine in patients with relapsed or refractory B-cell acute lymphoblastic leukemia, and to preliminarily assess tumor targeting and efficacy., Design and Methods: Three cohorts of patients received escalating doses of monoclonal antibody 216 administered as an intravenous infusion. In the case of poor response to the first dose of monoclonal antibody 216 alone, defined as less than 75% reduction in peripheral blood blast count, a second dose of the antibody with vincristine was given between days 4 and 7. Responses were assessed weekly until day 35. Serum concentration of monoclonal antibody 216 was measured before and after infusion. Monoclonal antibody 216 targeting was determined with an anti-idiotypic antibody to monoclonal antibody 216 and preliminary efficacy was analyzed by changes in peripheral blood blasts., Results: Thirteen patients were enrolled. One episode of grade 3 epistaxis was the only dose-limiting toxicity observed. All patients showed a poor response to the first monoclonal antibody 216 infusion with a decrease in peripheral blasts from 6-65% in 9 patients. In 8 patients, addition of vincristine to monoclonal antibody 216 resulted in an average reduction of the peripheral blasts of 81%. One patient without peripheral blasts achieved a hypoplastic marrow without evidence of leukemia after one infusion of monoclonal antibody 216 and monoclonal antibody 216/vincristine each. Monoclonal antibody 216 was detected on peripheral blasts in all patients., Conclusions: Treatment with monoclonal antibody 216 in combination with vincristine is feasible and well tolerated in patients with relapsed or refractory B-cell acute lymphoblastic leukemia. Binding of monoclonal antibody 216 to leukemic blasts was efficient, and favorable early responses were observed.

Purpose: The case of a patient receiving long-term anticoagulation with warfarin who had supratherapeutic International Normalized Ratios (INRs) after receiving concomitant acetaminophen and moxifloxacin as prophylaxis with bacille Calmette-Guérin (BCG) therapy for bladder cancer is reported., Summary: An 89-year-old man receiving long-term anticoagulation with warfarin sodium (total weekly dosage of 19 mg) arrived at the anticoagulation clinic for his monthly visit. On the day before this visit, he had received the third of six serial weekly BCG bladder instillations for the treatment of bladder cancer. He did not report that acetaminophen 1000 mg four times daily and one dose of moxifloxacin 400 mg had been prescribed before these instillations. An INR check revealed a value of 6.7. He was instructed to take 2.5 mg of oral phytonadione and to withhold his warfarin dose that night. On the next day, his INR was 3.2. Each time he arrived at the anticoagulation clinic after his BCG therapy, his INR was supratherapeutic, except after his fourth treatment (INR of 2.5), which can be explained by residual effects from the phytonadione he received a week earlier. After completion of his BCG therapy, he was instructed to resume his usual warfarin sodium dosage of 19 mg weekly, and his INR remained in the desired therapeutic range. According to the Drug Interaction Probability Scale, the development of supratherapeutic INRs was probably associated with concomitant acetaminophen and moxifloxacin use., Conclusion: An 89-year-old man receiving long-term anticoagulation with warfarin had supratherapeutic INRs after receiving acetaminophen and moxifloxacin as prophylaxis during BCG therapy for bladder cancer.

The majority of patients with acute myeloid leukemia (AML) will require second-line chemotherapy for either relapsed or refractory disease. Currently, only allogeneic hematopoietic cell transplantation (HCT) offers a curative option in this setting and no preferred regimen has been established. The reported efficacy of second-line regimens is widely disparate, thus limiting informed clinical decision making. A retrospective review of 77 patients receiving therapy between 2001 and 2008 with relapsed, 42, and refractory, 35, AML was performed to determine overall response rate and survival following mitoxantrone (8 mg/m(2)/day), etoposide (100 mg/m(2)/day), and cytarabine (1,000 mg/m(2)/day) chemotherapy administered over 5 days. Among 77 patients (median age of 54 years and 64% intermediate risk karyotype) with median follow-up of 153 days, 18% achieved a complete response and 8% a morphologic leukemia-free state. Fifty-seven (74%) experienced treatment failure, 10 of whom achieved a remission after additional therapy. Median overall survival (OS) was 6.8 months. Among patients achieving a response, 50% received consolidation with allogeneic HCT, autologous HCT (5%), or consolidation chemotherapy alone (45%). A nonsignificant trend in overall response (50%, 27%, and 23.8%) and median OS (8.3, 6.8, and 4.7 months) was observed by cytogenetic stratification into favorable, intermediate, and unfavorable risk. Patients with refractory versus relapsed disease had similar overall responses (20% and 31%, P = 0.41) and median OS (5.3 and 7.6 months, P = 0.36). Despite risk stratification by the European Prognostic Index, our series demonstrates inferior rates of response and survival, illustrating the limited activity of this regimen in our cohort., (© 2010 Wiley-Liss, Inc.)

Objective: Warfarin dosing remains challenging because of its narrow therapeutic window and large variability in dose response. We sought to analyze new factors involved in its dosing and to evaluate eight dosing algorithms, including two developed by the International Warfarin Pharmacogenetics Consortium (IWPC)., Methods: we enrolled 108 patients on chronic warfarin therapy and obtained complete clinical and pharmacy records; we genotyped single nucleotide polymorphisms relevant to the VKORC1, CYP2C9, and CYP4F2 genes using integrated fluidic circuits made by Fluidigm., Results: When applying the IWPC pharmacogenetic algorithm to our cohort of patients, the percentage of patients within 1 mg/d of the therapeutic warfarin dose increases from 54% to 63% using clinical factors only, or from 38% using a fixed-dose approach. CYP4F2 adds 4% to the fraction of the variability in dose (R) explained by the IWPC pharmacogenetic algorithm (P<0.05). Importantly, we show that pooling rare variants substantially increases the R for CYP2C9 (rare variants: P=0.0065, R=6%; common variants: P=0.0034, R=7%; rare and common variants: P=0.00018; R=12%), indicating that relatively rare variants not genotyped in genome-wide association studies may be important. In addition, the IWPC pharmacogenetic algorithm and the Gage (2008) algorithm perform best (IWPC: R=50%; Gage: R=49%), and all pharmacogenetic algorithms outperform the IWPC clinical equation (R=22%). VKORC1 and CYP2C9 genotypes did not affect long-term variability in dose. Finally, the Fluidigm platform, a novel warfarin genotyping method, showed 99.65% concordance between different operators and instruments., Conclusion: CYP4F2 and pooled rare variants of CYP2C9 significantly improve the ability to estimate warfarin dose.

Triterpenoids are a novel class of compounds being investigated as potential therapeutic agents for the treatment of prostate cancer and other malignancies. Asiatic acid (AA) is a member of the ursane family of triterpenoids and has anticancer activity, but its mechanism of action is not completely understood. To investigate its mechanism of action, PPC-1 prostate cancer cells were treated with AA at increasing concentrations and times. AA induced rapid caspase-dependent and independent cell death that peaked within 8 h of treatment. AA-induced death was associated with early activation of caspases 2, 3, and 8, but not caspase 9. Within 2.5 h of treatment, release of calcium from intracellular stores and dilatation of the endoplasmic reticulum was observed. Thus, disruption of the endoplasmic reticulum and alterations in calcium homeostasis are early events in AA-induced death.

The p53 tumor suppressor promotes cell cycle arrest or apoptosis in response to diverse stress stimuli. p53-mediated cell death depends in large part on transcriptional up-regulation of target genes. One of these targets, P53-induced protein with a death domain (PIDD), was shown to function as a mediator of p53-dependent apoptosis. Here we show that PIDD is a cytoplasmic protein, and that PIDD-induced apoptosis and growth suppression in embryonic fibroblasts depend on the adaptor protein receptor-interacting protein (RIP)-associated ICH-1/CED-3 homologous protein with a death domain (RAIDD). We provide evidence that PIDD-induced cell death is associated with the early activation of caspase-2 and later activation of caspase-3 and -7. Our results also show that caspase-2(-/-), in contrast to RAIDD(-/-), mouse embryonic fibroblasts, are only partially resistant to PIDD. Our findings suggest that caspase-2 contributes to PIDD-mediated cell death, but that it is not the sole effector of this pathway.

The purpose of this study was to evaluate pediatric patients with systemic lupus erythematosus (SLE) to determine 1) the incidence of thrombosis, 2) the incidence of antiphospholipid antibodies, and 3) whether there is an association between the presence of antiphospholipid antibodies and thrombosis. We performed a cross-sectional cohort study in 59 consecutive SLE patients who had been managed at rheumatology clinics in two pediatric hospitals. A history, questionnaire, and chart review were completed by the study nurse blinded to laboratory results. Only the thrombotic events that could be substantiated by review of radiographic tests were accepted. The presence of antiphospholipid antibodies was determined by prospective analysis for a lupus anticoagulant and anticardiolipin antibodies on two separate occasions at least 3 mo apart. Patients were considered to be positive if one or more tests were positive on both occasions. Thirteen thrombotic events occurred in 10 of the 59 patients (17%). Fourteen patients (24%) were classified as positive for lupus anticoagulant, and 19 patients (27%) were classified as positive for anticardiolipin antibodies. A significant relationship between the presence of a lupus anticoagulant and a thrombotic event was shown: odds ratio 28.7 (95% confidence interval 4.03-138.2, p < 0.001). A nonsignificant trend was seen for the presence of an anticardiolipin antibody and a thrombotic event: odds ratio 2.12 (95% confidence interval 0.71-22.8, p=0.08). We conclude that in pediatric patients with SLE: 1) a significant proportion of patients have thrombotic events, 2) a significant proportion of patients have antiphospholipid antibodies, and 3) there is a significant relationship between the presence of a lupus anticoagulant and thrombotic events.

An acquired IgG inhibitor to factor XIII was identified in a 30-year-old Vietnamese woman with systemic lupus erythematosus. The IgG fraction was isolated from plasma by chromatography on an agarose gel column and by protein G adsorption. The anti-factor XIII activity, identified within the IgG fraction, inhibited factor XIII from both normal plasma (a2b2) and platelets (a2). A normal level of the b subunit was measured by immunoelectrophoresis of the patient's plasma, but the a subunit was not detected. These results suggested the presence of an IgG immunoglobulin which recognized the a subunit and interfered with its activity.

Models of biogenic carbon (BC) flux assume that short herbivorous food chains lead to high export, whereas complex microbial or omnivorous food webs lead to recycling and low export, and that export of BC from the euphotic zone equals new production (NP). In the Gulf of St. Lawrence, particulate organic carbon fluxes were similar during the spring phytoplankton bloom, when herbivory dominated, and during nonbloom conditions, when microbial and omnivorous food webs dominated. In contrast, NP was 1.2 to 161 times greater during the bloom than after it. Thus, neither food web structure nor NP can predict the magnitude or patterns of BC export, particularly on time scales over which the ocean is in nonequilibrium conditions.