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Rationale and Objectives: In response to COVID-19, our institution implemented three virtual readout systems: a commercial HIPAA compliant web-based video conferencing platform used for screen-sharing (Starleaf), an interactive control sharing system integrated into PACS allowing simultaneous multi-user mouse control over images (Collaborate), and the telephone. Our aim was to assess overall satisfaction with and perceived effectiveness of these virtual readout methods to optimize best practices for the future., Materials and Methods: An IRB-exempt survey was electronically distributed to 64 trainees and 76 attendings at one tertiary-care institution via Survey Monkey. Questions focused on overall satisfaction, perceived effectiveness, technical difficulties, and continued future use of the three virtual readout strategies. Answers were collected with Likert scales, tick boxes, and open-ended questions., Results: 32/64 trainees (50%) and 32/76 attendings (42%) completed the survey. Trainees and attendings were more satisfied with screen sharing (Starleaf) and perceived it more effective than control sharing (Collaborate) or the telephone (p < 0.0001). Respondents experienced more technical difficulties with control sharing versus screen sharing (p = 0.0004) with a negative correlation between level of technical difficulties and satisfaction with screen sharing (r = -0.50, p < 0.0001) and control sharing (r = -0.38, p = 0.0006). Trainees and faculty supported a combination of in-person and virtual readouts in the future (p < 0.0001)., Conclusion: Platforms mirroring in-person readouts, such as Starleaf, are preferred by both trainees and attendings over non-screen sharing platforms such as the telephone. However, technical stability determines satisfaction between similar platforms. Both trainees and attendings support incorporation of virtual readout methods in combination with traditional in-person readouts in the post-COVID-19 era., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Minority older adults face multiple barriers when trying to access mental health services and often present with more severe symptoms of mental health conditions. We describe the multilevel factors that contributed to the engagement of an Asian immigrant older adult with depression. Systems-level innovations such as collaborative care in primary care can increase access to care for all, including minority older adults; however, one size fits all interventions may not meet the needs of communities of older adults with different life experiences, language needs, norms and values regarding help-seeking for mental health. Health outcomes remain unequal , suggesting the need to tailor interventions for minority older adults. For the patient, specific factors related to language and ethnic concordance between patient and healthcare provider, communication behaviors, ethnic identity, and social norms may be important to take into account. The recognition of the heterogeneity of patients and the limitations of cultural competence approaches defined as broad, general knowledge about ethnic cultures may be needed. A need to learn continuously from clinical experience and adopt a patient-oriented model of communication and decision-making may successfully engage Asian immigrant older adults in depression care services., Competing Interests: Disclosure The authors have no conflicts of interest to declare., (Copyright © 2021 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Patients with coronary artery disease (CAD) who also have peripheral artery disease (PAD) are at high risk of subsequent cardiovascular events and mortality. Despite this, PAD in patients with CAD often remains undiagnosed. The objective of this analysis was to assess clinical factors that predict the presence of PAD in patient with documented CAD who also have PAD., Methods: In a post hoc analysis of patients with CAD in the COMPASS trial, we developed separate prediction models for symptomatic lower extremity PAD and documented carotid artery disease (Model 1), asymptomatic lower extremity PAD defined as ABI <0.9 (Model 2) and for any PAD (symptomatic or asymptomatic; Model 3). Using logistic regression models, candidate variables were chosen to predict the presence of PAD. Overall model performance was evaluated for discrimination and calibration using the concordance statistic and Hosmer and Lemeshow Goodness-of-fit chi-square, respectively. The final model was validated by bootstrapping., Results: Of 23,402 participants, 3484 (14.9%) had a history of symptomatic PAD or carotid artery disease (Model 1), 1422 (5.7%) participants had asymptomatic PAD (Model 2) and 4906 (20.6%) had any PAD (Model 3). Model 1 demonstrated a C-statistic of 0.667 and goodness-of-fit p-value of 0.859. Model 2 demonstrated a C-statistic of 0.626 and goodness-of-fit p-value of 0.250. Model 3 demonstrated a C-statistic of 0.646 and goodness-of-fit p-value of 0.240., Conclusion: Routinely available clinical information is only marginally useful to identify patients with CAD and concomitant PAD., 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 © 2021 Elsevier B.V. All rights reserved.)

Background: Spontaneous intracerebral hematoma (ICH) is a common disease with a dismal overall prognosis. Recent development of minimally invasive ICH evacuation techniques has shown promising results. Commercially available tubular retractors are commonly used for minimally invasive ICH evacuation yet are globally unavailable., Methods: A novel U.S. $7 cost-effective, off-the-shelf, atraumatic tubular retractor for minimally invasive intracranial surgery is described. Patients with acute spontaneous ICH underwent microsurgical tubular retractor-assisted minimally invasive ICH evacuation using the novel retractor. Patient outcome was retrospectively analyzed and compared with open surgery and with commercial tubular retractors., Results: Ten adult patients with spontaneous supratentorial ICH and median preoperative Glasgow Coma Scale score of 10 were included. ICH involved the frontal lobe, parietal lobe, occipitotemporal region, and solely basal ganglia in 3, 3, 2, and 2 patients, respectively. Mean preoperative ICH volume was 80 mL. Mean residual hematoma volume was 8.7 mL and mean volumetric hematoma reduction was 91% (median, 94%). Seven patients (70%) underwent >90% volumetric hematoma reduction. The total median length of hospitalization was 26 days. On discharge, the median Glasgow Coma Scale score was 12.5 (mean, 11.7). Thirty to 90 days' follow-up data were available for 9 patients (90%). The mean follow-up modified Rankin Scale score was 3.7 and 5 patients (56%) had a modified Rankin Scale score of 3., Conclusions: The novel cost-effective tubular retractor and microsurgical technique offer a safe and effective method for minimally invasive ICH evacuation. Cost-effective tubular retractors may continue to present a valid alternative to commercial tubular retractors., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Prior single-site evaluations of Child Adult Relationship Enhancement in Primary Care (PriCARE), a 6-session group parent training, demonstrated reductions in child behavioral problems and improvements in positive parenting attitudes., Objective: To measure the impact of PriCARE on disruptive child behaviors, parenting stress, and parenting attitudes in a multisite study., Methods: Caregivers of children 2- to 6-year-old with behavior concerns recruited from 4 pediatric primary care practices were randomized 2:1 to PriCARE intervention (n = 119) or waitlist control (n = 55). Seventy-nine percent of caregivers identified as Black and 59% had annual household incomes under $22,000. Child behavior, parenting stress, and parenting attitudes were measured at baseline and 2 to 3 months after intervention using the Eyberg Child Behavior Inventory, Parenting Stress Index, and Adult-Adolescent Parenting Inventory-2. Marginal standardization implemented in a linear regression compared mean change scores from baseline to follow-up by treatment arm while accounting for clustering by site., Results: Mean change scores from baseline to follow-up demonstrated greater improvements (decreases) in Eyberg Child Behavior Inventory problem scores but not intensity scores in the PriCARE arm compared to control, (problem: -4.4 [-7.5, -1.2] vs -1.8 [-4.1, 0.4], P= .004; intensity: -17.6 [-28.3, -6.9] vs -10.4 [-18.1, -2.6], P= .255). Decreases in parenting stress were greater in the PriCARE arm compared to control (-3.3 [-4.3, -2.3] vs 0 [-2.5, 2.5], P= .025). Parenting attitudes showed no significant changes (all P> .10)., Conclusions: PriCARE showed promise in improving parental perceptions of the severity of child behaviors and decreasing parenting stress but did not have an observed impact on parenting attitudes., (Copyright © 2020 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

Background: The necessity and timing of early postoperative imaging (POI) are debated in many studies. Despite the consensus that early POI does not change patient management, these examinations are routinely performed. This is the first prospective study related to POI. Our aims were to assess the necessity of early POI in asymptomatic patients and to verify accuracy of the presented algorithm., Methods: This was an algorithm-based prospective single-center study. The algorithm addressed preoperative, perioperative, and postoperative considerations, including estimated pathology type, device placement, and postoperative neurologic change. Early computed tomography scans were obtained in all patients, but if postoperative algorithm indications did not recommend a scan, the treating team was blinded to them, and patient management was conducted based on clinical examinations alone. A neuroradiologist and study-independent neurosurgeon reviewed all the scans., Results: Of 103 enrolled patients, 88 remained asymptomatic, and 15 experienced symptoms postoperatively. Pathology was present on POI in 1% of the asymptomatic patients and 53% of the symptomatic patients (P < 0.001). In the asymptomatic group, no treatment modifications were made postoperatively. Blinding of the surgical team was not removed, and 20% of the symptomatic patients returned to the operating room because of imaging and neurologic findings. The goal of <5% algorithm failure was reached with statistical significance., Conclusions: In asymptomatic postoperative patients in whom early imaging is not performed for oncologic indications, device placement verification, or similar reasons, POI is unnecessary and does not change the management of these patients., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Exposure to traumatic experiences among youth is a serious public health concern. A trauma-informed public behavioral health system that emphasizes core principles such as understanding trauma, promoting safety, supporting consumer autonomy, sharing power, and ensuring cultural competence, is needed to support traumatized youth and the providers who work with them. This article describes a case study of the creation and evaluation of a trauma-informed publicly funded behavioral health system for children and adolescents in the City of Philadelphia (the Philadelphia Alliance for Child Trauma Services; PACTS) using the Exploration, Preparation, Implementation, and Sustainment (EPIS) as a guiding framework. We describe our evaluation of this effort with an emphasis on implementation determinants and outcomes. Implementation determinants include inner context factors, specifically therapist knowledge and attitudes (N=114) towards evidence-based practices. Implementation outcomes include rate of PTSD diagnoses in agencies over time, number of youth receiving TF-CBT over time, and penetration (i.e., number of youth receiving TF-CBT divided by the number of youth screening positive on trauma screening). We describe lessons learned from our experiences building a trauma-informed public behavioral health system in the hopes that this case study can guide other similar efforts., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Four-factor prothrombin complex concentrates (PCCs), which contain factor II, FVII, FIX, and FX, have shown the potential to reverse the anticoagulant effect of rivaroxaban in healthy volunteers. The purpose of this study was to determine whether a three-factor PCC, which contains little FVII, has a similar effect., Methods and Results: We performed an open-label, single-center, parallel-group study comparing the effect of a three-factor PCC (Profilnine SD) with that of a four-factor PCC (Beriplex P/N) on the pharmacodynamics of rivaroxaban in 35 healthy volunteers. After receiving 4 days of rivaroxaban 20 mg twice daily to obtain supratherapeutic steady-state concentrations, volunteers were randomized to receive a single 50 IU kg(-1) bolus dose of four-factor PCC, three-factor PCC or saline 4 h after the morning dose of rivaroxaban on day 5, and the effects of these interventions on prothrombin time and thrombin generation were determined. Within 30 min, four-factor PCC reduced mean prothrombin time by 2.5-3.5 s, whereas three-factor PCC produced only a 0.6-1.0-s reduction. In contrast, three-factor PCC reversed rivaroxaban-induced changes in thrombin generation more than four-factor PCC., Conclusions: This study demonstrates the potential of both three-factor and four-factor PCCs to at least partially reverse the anticoagulant effects of rivaroxaban in healthy adults. The discrepant effects of the PCC preparations may reflect differences in the procoagulant components present in each., (© 2014 International Society on Thrombosis and Haemostasis.)

Background: Diabetes complications account for significant worldwide morbidity and mortality. Improving glycemic control decreases microvascular complications, particularly among patients with the worst control. Current performance measures fail to prioritize such individuals. The categorization of glycemic control within a safety-net clinic population was compared using a common performance measure against one derived from a metric accounting for change in glycated hemoglobin (A1c) over time., Methods: Retrospective cohort analysis of all patients in a safety-net primary care clinic population quality registry with confirmed diabetes mellitus who had at least two A1c values between 2007 through 2011. Patients were stratified into five groups' on the basis of maximum and earliest A1c level (< 7%, 7% to < 8%, 8% to < 9%, 9% to < 10%, and > 10%). The change in Alc was assessed over time and compared with standard healthcare effectiveness data and information set (HEDIS) performance measures., Results: Some 1122 patients were included in the analysis, with mean A1c of 7.9%. There was a modest annual decrease in the average A1c, and > 19% of patients improved by 1% or more during each of the previous three years. For patients who had maximum A1c values > or = 10%, there was a significantly greater reduction in A1c (p < .01), which was not reflected in the standard performance measure., Conclusions: It is feasible for safety-net clinics to analyze their patients with diabetes by level of disease control on the basis of change in A1c over time. Patients with the worst glycemic control tend to have the greatest improvement but are often overlooked by conventional performance measures. Improved performance measures should focus on longitudinal diabetes control and emphasize reducing risk of complications among patients at highest risk.

Background: Prophylaxis is recommended following total joint replacement because of the high risk of venous thromboembolism (VTE). Postoperative low-molecular-weight heparin (LMWH) reduces the incidence of venographically detected deep vein thrombosis (DVT) to about 10-15% in total hip replacement (THR) patients. Ximelagatran is a novel, oral direct thrombin inhibitor that selectively and competitively inhibits both free and clot-bound thrombin. We compared the efficacy and safety of ximelagatran with those of enoxaparin for the prevention of VTE in patients undergoing THR., Methods: This was a prospective, randomized, multicenter, double-blind study conducted principally in the USA and Canada. Patients received fixed-dose oral ximelagatran 24 mg bid or subcutaneous enoxaparin 30 mg bid and matched placebo for 7-12 days; both regimens were initiated the morning after surgery. The incidence of VTE (by postoperative day 12) included thrombosis determined by mandatory venography of the leg on which surgery was performed and symptomatic, objectively proven DVT or pulmonary embolism (PE). VTE and bleeding events were interpreted by an independent central adjudication committee for primary analysis., Results: Of the 1838 patients randomized, 1557 had either adequate venography or symptomatic, proven VTE (efficacy population). Overall rate of venography acceptable for evaluation was 85.4%. Overall rates of total VTE were 7.9% (62 of 782 patients) in the ximelagatran group and 4.6% (36 of 775 patients) in the enoxaparin group, with an absolute difference of 3.3% and a 95% confidence interval for the difference of 0.9% to 5.7%. Proximal DVT and/or PE occurred in 3.6% (28 of 782 patients) in the ximelagatran group and 1.2% (nine of 774 patients) in the enoxaparin group. Major bleeding events were observed in 0.8% (seven of 906) of the ximelagatran-treated patients and in 0.9% (eight of 910) of the enoxaparin-treated patients (P > 0.95). Non-inferiority of ximelagatran 24 mg bid based on a prespecified margin of 5% was not met, resulting in superiority of the enoxaparin regimen., Conclusions: Both ximelagatran and enoxaparin decreased the overall rate of VTE compared with that reported historically. However, in this study, enoxaparin 30 mg bid was more effective than ximelagatran 24 mg bid for prevention of VTE in THR. Oral ximelagatran was used without coagulation monitoring, was well tolerated, and had bleeding rates comparable to those of enoxaparin. Further refinement by testing a higher dose of ximelagatran in the patients undergoing THR is warranted.

Background: Unfractionated heparin (UFH) is safe and effective for thromboprophylaxis, but its use is limited to parenteral administration. A novel drug delivery agent (SNAC) has been developed to accomplish the oral delivery of heparin., Objective: This report describes the foundation for dose selection and use of oral heparin/SNAC in patients undergoing elective total hip arthroplasty (THA)., Patients and Methods: To develop a treatment regimen for clinical study, a multiple dose Phase I pharmacokinetic (PK) study in healthy volunteers compared oral heparin/SNAC (90 000 U heparin) with subcutaneous UFH (5000 U). On this basis, we carried out a double-blind, randomized, multicenter study comparing subcutaneous UFH (5000 U) with oral heparin/SNAC at either 60 000 or 90 000 U heparin in 123 patients undergoing elective THA. Patients received, postoperatively, one of the three treatments every 8 h for a total of 12 doses and were followed for 35 days post surgery., Results: In the Phase I study, anti-factor Xa activity peaked at 45-60 min following oral heparin/SNAC, returning to baseline at 4 h. RESULTS of the randomized trial in THA patients showed that venous thromboembolic events (n = 6), major bleeding events (n = 5) and need for transfusion (n = 23) were distributed evenly among the three treatment groups, UFH and both doses of oral heparin/SNAC., Conclusion: This is the first demonstration that oral heparin/SNAC can be safely delivered to the postoperative THA patient, and provides the basis for a larger clinical trial to assess the prophylactic efficacy of heparin/SNAC.

The behavior of plasma von Willebrand factor (vWF) in patients with acute leukemia (n = 5), decompensated cirrhosis (n = 10), and acute pancreatitis (n = 5) was investigated to evaluate whether the systemic proteolytic states associated with these diseases had affected the structure and function of the molecule. vWF antigen and, to a lesser degree, ristocetin cofactor activity in patient plasma were high. Multimeric analysis of plasma vWF revealed loss of high molecular weight multimers. The subunit composition and proteolytic pattern of vWF immunopurified from patient plasmas and reduced were studied by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis followed by transblotting and probing with monoclonal antibodies that distinguish cleavages caused by plasmin from those caused by other proteases. There was marked reduction of the relative concentration of the native vWF subunit of 225 Kd in all patient groups, indicating heightened cleavage of the protein. The concentrations of 189- and 140-Kd vWF fragments, normally present in plasma, were increased in cirrhosis and pancreatitis but not in leukemia. Novel fragments, ranging in size from less than 225 to approximately 120 Kd were present in leukemia and cirrhosis, including plasmin-generated fragments of 176 and 145 Kd. These data indicate that in clinical conditions in which there is heightened proteolysis vWF is degraded in vivo by plasmin and other proteases. Degraded vWF may be less effective than native vWF in supporting primary hemostasis, thereby being a cofactor in the multifactorial bleeding diathesis accompanying systemic proteolytic states.

In 20 patients with acute myocardial infarction (AMI) treated with streptokinase (SK, n = 7), recombinant single-chain tissue plasminogen activator (rt-PA, n = 7) or urokinase (UK, n = 6), the behavior of plasma von Willebrand factor (vWF) was studied before and 1.5, 3, 24, 48, and 72 hours after beginning thrombolytic therapy. vWF antigen (vWF:Ag) was high in plasma, especially after SK. The ristocetin cofactor (RiCof) activity of vWF, high before therapy, tended to decrease soon after therapy. This pattern of vWF changes was paralleled by the early loss of higher molecular weight multimers. By immunoblotting of immunopurified and reduced vWF and monoclonal antibody epitope mapping, we found that vWF was degraded after thrombolysis, especially after SK, as indicated by the higher values of two plasmin-generated fragments of 176 and 145 Kd. There were more plasmin-generated fragments in the five patients who had bleeding complications than in the remaining 15 who did not. In conclusion, quantitative and qualitative changes of vWF compatible with proteolytic degradation of the protein occur during thrombolytic therapy. Such degradation, roughly proportional to the degree of the general lytic state induced by each agent, might be a cofactor of the bleeding complications occurring in treated patients.

Removal of sialic acid from the von Willebrand factor (vWF) subunit exposes additional cleavage sites in the amino-terminal region that are associated with loss of large multimers. The extent of large multimer loss was evaluated by examining the sites of subunit cleavage of native and carbohydrate-modified vWF after treatment with trypsin, chymotrypsin, or plasmin. In the presence of proteinase inhibitors, purified vWF was treated with neuraminidase alone to remove 90% to 95% of the sialic acid or with neuraminidase and beta-galactosidase to remove the sialic acid and 45% to 50% of the D-galactose, with little or no loss of large multimers observed. Digestion of native vWF with trypsin produced the greatest loss of large multimers, while chymotrypsin produced less and plasmin produced the least. Large multimer loss was more extensive with each enzyme after carbohydrate modification of vWF. The extent and approximate location of subunit cleavage was determined by immunoblotting and monoclonal antibody epitope mapping. Trypsin, chymotrypsin, and plasmin were shown to produce both amino- and carboxyl-terminal fragments. The number, location, and relative quantities of carboxyl-terminal fragments produced were unchanged after carbohydrate modification. However, digestion of the amino-terminal region was considerably more extensive after carbohydrate modification as judged by a marked decrease or absence of the larger fragments seen when native vWF was digested, and by the appearance of new smaller molecular mass species. Therefore, the greater loss of large multimers that occurs after carbohydrate modification is likely to be the result of cleavages in the amino-terminal region of the molecule. By protecting the vWF subunit against amino-terminal cleavage, sialic acid inhibits the loss of large multimers.

In order to evaluate the role of proteolysis in acquired von Willebrand's disease (vWD) associated with the myeloproliferative syndrome, we have determined the relative quantity of von Willebrand factor (vWF) fragments as compared with the intact 225 kDa subunit in four patients. The plasma vWF of each individual lacked large multimers; each had a prolonged bleeding time; and both platelet and leukocyte counts were elevated. Plasma was obtained from blood drawn into 1 mmol/L leupeptin, 6 mmol/L N-ethylmaleimide, and 5 mmol/L EDTA to prevent in vitro proteolysis. vWF was isolated from plasma by immunoadsorbent chromatography, reduced, subjected to SDS-5% polyacrylamide gel electrophoresis, and immunoblotted with a mixture of 55 anti-vWF monoclonal antibodies. In three patients with essential thrombocytosis (ET) the 176 and 140 kDa fragments were increased in proportion to the intact 225 kDa subunit indicating increased proteolysis. Treatment of one ET patient with CCNU (Lomustine) decreased the platelet count and, to a lesser extent, the white blood cell count. This was associated with a correction of the bleeding time, a partial correction of the multimeric abnormality, and a lessening of vWF cleavage. In a patient with polycythemia rubra vera (PRV) the proportion of the 176 kDa fragment was increased to the upper limit of normal but there was no definite evidence of increased proteolysis. These studies provide evidence that proteolysis plays a role in the acquired von Willebrand's disease associated with the myeloproliferative syndrome. However, other mechanisms must also be considered.

The infusion of 1-deamino-8-D-arginine vasopressin (DDAVP) in normal individuals is followed by an increase in factor VIII/von Willebrand factor (vWF) in plasma, by an increase in intensity of all sizes of multimers, and by the appearance of larger multimers of vWF than those seen in the resting state. Since the larger multimers are rapidly cleared and proteolysis is known to cause disaggregation of large multimers, we evaluated the degree of vWF proteolysis after DDAVP administration. DDAVP was infused into eight normal adult volunteers, and the relative proportions of the intact 225 kilodalton (kDa) subunit and the 189, 176, and 140 kDa vWF fragments were compared before and at different times after DDAVP infusion. The relative proportion of the 176 kDa fragment was increased, whereas that of the other species was decreased, thereby indicating that proteolytic fragmentation had occurred. However, plasmin did not appear to be responsible because the vWF fragments characteristically produced by this enzyme could not be detected. Concomitant analysis of vWF multimeric structure showed that these changes were accompanied by an increase in the relative proportion of the satellite bands, which suggests that they were proteolytically generated. Proteolysis may explain, at least in part, rapid clearance of larger vWF multimers released by DDAVP.

Four diets were fed to pony fillies for 40 weeks. One group received a basal diet low in carotene, designated mildly deficient. Other groups were fed basal diet plus vitamin A propionate equivalent to 12 (control), 1,200 (mildly intoxicated) or 12,000 (severely intoxicated) microgram retinol/kg body weight/day. The mildly deficient group exhibited impairment of growth and hematopoiesis with decreased serum concentrations of iron, albumin and cholesterol prior to depletion of liver vitamin A. Growth was depressed in mildly intoxicated and severely intoxicated fillies. The latter became debilitated and died in less than 40 weeks with reduced serum concentrations of iron, albumin and cholesterol. Significant associations were calculated between dietary vitamin A and vitamin A concentrations in plasma, liver and kidney, and between plasma vitamin A and liver and kidney vitamin A. Plasma retinyl ester increased logarithmically with plasma total vitamin A and linearly with kidney vitamin A. The data suggest that increases in retinyl ester due to excessive dietary vitamin A occur prior to appearance of clinical signs and perhaps reflect kidney vitamin A levels. Calculated estimates of optimal vitamin A intake fo maximal growth averaged 1.4 times the current National Research Council recommendation, for liver secreted serum constituents 5.4 times and for red blood cell criteria 10 times. Thus the recommended intake of 12 microgram/kg for weanling horses appears less than optimal. The data suggest hematologic criteria and serum biochemistries may be more sensitive indicators of vitamin A nutriture than growth.

Rapid preparative scale purification of calmodulin from crude bovine brain extract is achieved in a single chromatographic run by physically coupling two different liquid chromatography columns which employ different separation mechanisms. In this case columns packed with newly commercialized 40-microns silica-based hydrophobic interaction and 5-microns micron silica-based weak anion-exchange chromatography media were used. The only sample preparation required for conducting this purification procedure is the addition of salt to the crude brain supernatant to promote the initial binding of calmodulin to the hydrophobic interaction chromatography media. Chromatography carried out on such linear arrangements of columns has been referred to as linear multidimensional liquid chromatography.

Recent evidence suggests that proteolysis plays an important role in some forms of inherited and acquired von Willebrand disease (vWD). Because calpains and one or more enzymes released from polymorphonuclear leukocytes are known to proteolyze von Willebrand factor (vWF) in vitro with resultant loss of large multimers similar to that seen in IIA vWD, they have been suggested as being responsible for the proteolysis in vivo. Using monoclonal epitope mapping, we have examined the proteolysis of the vWF subunit by porcine calcium-activated neutral proteases (calpains) and human leukocyte elastase to determine whether they produce the vWF proteolytic cleavage products seen in normal individuals and IIA vWD. Purified vWF was digested with porcine calpains I and II. We found no difference in the size, location, and quantity of the fragments produced by calpain I v calpain II. New fragments were detected of approximately 200, 170, 150, and 125 Kd. There was no evidence for generation of the native 140 and 176 Kd fragments. Some loss of the native fragments was seen, which suggests that they were further cleaved. Epitope mapping of the 170- and 150-Kd calpain-cleaved fragments revealed them to be from different parts of the molecule than the regions from which the native 176- and 140-Kd fragments derived. This was further supported by determination of the amino-terminal sequence of the calpain-cleaved 170- and 150-Kd fragments. Digestion of vWF with human leukocyte elastase produced new fragments at 210/205, 190, 170/165, 145/140, and 130/125 Kd. No generation of native fragments was detected. Monoclonal epitope mapping of the 145/140-Kd elastase-cleaved band proved that it derived from the carboxyl-terminal portion of the vWF molecule, whereas the native 140-Kd fragment is derived from the amino-terminal end. Neither calpains nor human leukocyte elastase produced the proteolyzed fragments present in normal and IIA vWD and, therefore, probably do not cause the loss of large multimers that is seen in that disorder.

We describe a microcomputer system utilizing the Computerized Laboratory Notebook (CLN) concept developed in our laboratory for the purpose of automating the Battery of Leukocyte Tests (BLT). The BLT was designed to evaluate blood specimens for toxic, immunotoxic, and genotoxic effects after in vivo exposure to putative mutagens. A system was developed with the advantages of low cost, limited spatial requirements, ease of use for personnel inexperienced with computers, and applicability to specific testing yet flexibility for experimentation. This system eliminates cumbersome record keeping and repetitive analysis inherent in genetic toxicology bioassays. Statistical analysis of the vast quantity of data produced by the BLT would not be feasible without a central database. Our central database is maintained by an integrated package which we have adapted to develop the CLN. The clonal assay of lymphocyte mutagenesis (CALM) section of the CLN is demonstrated. PC-Slaves expand the microcomputer to multiple workstations so that our computerized notebook can be used next to a hood while other work is done in an office and instrument room simultaneously. Communication with peripheral instruments is an indispensable part of many laboratory operations, and we present a representative program, written to acquire and analyze CALM data, for communicating with both a liquid scintillation counter and an ELISA plate reader. In conclusion we discuss how our computer system could easily be adapted to the needs of other laboratories.