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Purpose The development of pediatric ventricular assist device (VAD) circuits with lower flow ranges for infants and small children is ongoing. We present our results with modifying a readily available adult VAD to support the pediatric population. Description The TandemHeart VAD (CardiacAssist, Pittsburgh, PA) circuit was modified to include a variable restrictive recirculation shunt to permit lower flow ranges in small pediatric patients. Evaluation Initial benchtop flow rates and pressures were studied. Hemolysis trials were performed using whole bovine blood to compare plasma-free hemoglobin levels between modified and unmodified VAD circuits. The modified VAD was surgically implanted in 7 piglets (6 to 14 kg) and which supported them for 4 hours. Levels of hemolysis did not increase and full hemodynamic support was achieved. The modified TandemHeart VAD with a recirculation shunt was subsequently implanted in 2 pediatric patients who were bridged to transplant successfully. Conclusions Because of its simplicity, availability, low prime volume, greater patient flow range, and lower cost, the modified TandemHeart VAD with a recirculation shunt should be considered as an alternative to extracorporeal membrane oxygenation and other pulsatile VADs in children.

Teenage pregnancy and childbearing remain pressing public health issues that have garnered attention from public health officials and social services agencies. This paper reports on the initial implementation and formative evaluation of a journaling program used as a means of communicating health information to pregnant and parenting adolescents (young women age 15-19) while also providing participants with a means of self-expression. The journaling prototype was implemented in a community-based agency in the Midwest by Family Support Specialists (FSSs) who made home visits on a monthly basis to assist pregnant and parenting adolescents (n=52) with successful family planning and public health education. A mixed method approach of qualitative (analysis of journals, field notes, and responses of semi-structured interviews with FSSs) and quantitative (questionnaires from pregnant and parenting adolescent respondents) data with purposive sampling was employed to evaluate the implementation of the journaling intervention. Twenty of the 52 study participants were pregnant when the journaling intervention was implemented, while 32 were not pregnant, but recently had a child and were currently parenting. Two core themes emerged from analysis of the data after the implementation of the journals: (1) usefulness of the journal and responsiveness to participants' information needs and (2) functionality challenges. The results offer practical starting points to tailor the implementation of journaling in other contexts. Further, areas for improvement emerged regarding the distribution timeline for the journal and the content of the journal itself. As such, we discuss the lessons learned through this collaborative project and suggest opportunities for future phases of the journal intervention.

Pain is the most common physical symptom in primary care, accounting for an enormous burden in terms of patient suffering, quality of life, work and social disability, and health care and societal costs. Although collaborative care interventions are well-established for conditions such as depression, fewer systems-based interventions have been tested for chronic pain. This paper describes the study design and baseline characteristics of the enrolled sample for the Stepped Care to Optimize Pain care Effectiveness (SCOPE) study, a randomized clinical effectiveness trial conducted in five primary care clinics. SCOPE has enrolled 250 primary care veterans with persistent (3 months or longer) musculoskeletal pain of moderate severity and randomized them to either the stepped care intervention or usual care control group. Using a telemedicine collaborative care approach, the intervention couples automated symptom monitoring with a telephone-based, nurse care manager/physician pain specialist team to treat pain. The goal is to optimize analgesic management using a stepped care approach to drug selection, symptom monitoring, dose adjustment, and switching or adding medications. All subjects undergo comprehensive outcome assessments at baseline, 1, 3, 6 and 12 months by interviewers blinded to treatment group. The primary outcome is pain severity/disability, and secondary outcomes include pain beliefs and behaviors, psychological functioning, health-related quality of life and treatment satisfaction. Innovations of SCOPE include optimized analgesic management (including a stepped care approach, opioid risk stratification, and criteria-based medication adjustment), automated monitoring, and centralized care management that can cover multiple primary care practices.

In this paper, we develop an inventory model for determining the optimal ordering policies for a buyer who operates an inventory policy based on an EOQ-type model with planned backorders when the supplier offers a temporary fixed-percentage discount and has specified a minimum quantity of additional units to purchase. A distinguishing feature of the model is that both fixed and linear backorder costs are included, whereas previous works include only the linear backordering cost. A numerical study is performed to provide insight into the behavior of the model. © 2009 Elsevier Inc. All rights reserved.

In the painted sheet metal industry, offering a great variety of colors is an important competitive factor. However, an excessive number of colors can lead to excessive setup costs/times, inventory costs, and administrative complexity. In this paper, we address the case of a large manufacturer of painted sheet metal products located in northern Mexico. Several methods, both exact and heuristic, are proposed to optimize the variety of colors the firm offers. The exact method is based on mixed integer programming and the heuristic methods are variations of greedy algorithms. The methods are tested with real company data. The methods that perform better are identified and considerations are discussed which can affect the choice of method in a practical setting.

In this paper, we develop a decomposition technique for the solution of a two-stage decision and scheduling problem in production environments. A tree search heuristic based on the decomposition approach is developed. We illustrate the procedure on the industry example of flat glass production.

Study objectives: To evaluate the chest radiographic filling pattern associated with partial liquid ventilation (PLV) with the perfluorochemical perflubron (LiquiVent; Alliance Pharmaceutical Corp; San Diego CA) as a function of dose and timing. Design: Post hoc review of chest radiographs by three independent observers with correlation to clinical variables. Setting: Phase II randomized, uncontrolled, prospective, multicenter clinical trial. Patients: Sixteen adult patients with diffuse bilateral infiltrates consistent with acute lung injury and a Pa o 2 /fraction of inspired oxygen (F io 2 ) ratio 2 O and F io 2 ≥ 0.5. Interventions: All patients were treated with either a 10-mL/kg or 20-mL/kg loading dose of perflubron followed by maintenance dosing at 3-h intervals to protocol-determined levels. Results: There was a significant relationship between inhomogeneous radiographic filling during the first 48 h of treatment and the use of the lower loading dose of perflubron. Inhomogeneous radiographic filling (in 5 patients) was associated with a lower high-dose/F io 2 ratio at 24 h compared with the remaining patients. These differences resolved by 48 h. There were no other statistically significant correlations identified. Conclusions: The radiographic appearance of PLV with perflubron appears to depend on the dose administered. Lower doses can be associated with both inhomogeneous radiographic filling and a transient deterioration in oxygenation during the first 24 to 48 h of treatment.

This study examined the relationships between older adults' likelihood of receiving a personal response system (PRS) and (1) predisposing characteristics (gender, race, marital status, age, and education level); (2) enabling characteristics (living alone, living in an extended family), and availability of informal (family/ friend) caregivers; and (3) need characteristics (physical and cognitive function). PRS applies modem communication technology to protect older adults living in the community by sending an automatic telephone call for help if a person at home cannot use normal means for signalling an emergency. The study sample consisted of older adults ( N = 553) living in rural areas of Arkansas and enrolled in a Medicaid waiver program for community-based services. Nurse case-managers evaluated the participants in their homes and decided whether PRS should be prescribed. Fifty-two percent of respondents were prescribed PRS free of charge by the nurse case-managers. We entered the three sets of characteristics into an adapted version of Andersen's behavioral model of health services utilization (Andersen, 1968, Andersen, 1995). We used logistic regression to evaluate the effects of predisposing, enabling, and need characteristics' relationships in relation to receipt of PRS. Based upon multivariate analysis, four variables—living alone, cognitive and physical function, and race—had statistically significant direct effects on PRS prescription. In other words, after adjusting for the effects of predisposing, enabling, and need characteristics, cognitive intactness and living alone had the strongest positive effects on receiving PRS, followed by being Caucasian and having difficulties performing activities of daily living (i.e., assistance needed with bathing, dressing, toileting, and moving in/out of bed/chairs). Our results should be of value in designing, planning, and implementing PRS systems in rural areas.

Objective: To report a rare case of sequential bilateral adnexal torsion in a pregnant woman after a single cycle of gonadotropin ovulation induction with IUI. To review the literature with regards to the causation and aspects of the management of adnexal torsion, particularly after assisted conception. Design: Case report. Setting: Fertility department within a teaching hospital. Patient(s): A 35-year-old woman with a twin pregnancy after a cycle of gonadotropin ovulation induction and IUI. Intervention(s): Gonadotropin ovulation induction with IUI; two laparotomies, salpingooophorectomy, stabilization of adnexa with stay suture. Result(s): Continuation of pregnancy until 37 weeks gestation with the abdominal delivery of healthy twins. Conclusion(s): The case of a woman with a multiple pregnancy and ovarian hyperstimulation syndrome after ovulation induction and IUI who developed sequential bilateral adnexal torsion is used to illustrate the risk factors and management options for adnexal torsion. Physicians should be aware of the increased incidence of adnexal torsion in the rising number of women undergoing ovulation induction in order to effect early surgical intervention and adnexal salvage. Consideration should be given to the anchoring of bulky adnexae to prevent torsion recurrence.

The antibiotic sensitivity of protein synthesis by mitochondria isolated from chick brain, trout liver, potato tuber and corn root has been investigated. Like mitochondria isolated from rat liver, organelles from these sources show a much reduced antibiotic sensitivity spectrum when compared to mitochondria derived from yeast, being sensitive to chloramphenicol, carbomycin, spiramycin and mikamycin but resistant to erythromycin, lincomycin, paromomycin, neomycin C and viridiogrisein. In addition spectinomycin inhibited protein synthesis by both types of plant mitochondria but not those from chick brain, rat liver or yeast.

The effect of temperature on the kinetics of protein synthesis by both free and membrane-bound ribosomes has been investigated. Free ribosomes isolated from rat liver conform to the predictions of the Arrhenius equation in that a plot of log of the amino acid incorporation rate against the reciprocal of the absolute temperature gives a simple linear relationship from which an Arrhenius activation energy(E) of 25.5 kcal/mole is calculated. However, similar plots of data for the protein synthetic activity of rough endoplasmic reticulum show two linear regions giving Arrhenius activation energies of 16 kcal/mole above 22 °C and 43 kcal/mole below this temperature. A phase change in the lipids of rough endoplasmic reticulum was demonstrated at 22 °C by electron spin resonance spectroscopy using a suitable lipophilic spin label. The importance of the membrane in the origin of the discontinuity in the Arrhenius plots was confirmed by experiments with reconstituted rough endoplasmic reticulum derived from inactive “stripped” membranes and free ribosomes. We conclude that phase changes occurring in the membrane as a consequence of lipid reorganization can influence the activity of ribosomes associated with the membranes.

Protein synthesis in intact rat liver mitochondria is strongly inhibited by chloramphenicol, mikamycin, carbomycin, and spiramycin but is insensitive to erythromycin, lincomycin, and paromomycin. We have investigated methods of damaging the mitochondrial membrane to destroy any possible permeability barriers to these latter antibiotics. Criteria to demonstrate the access of antibiotics to the mitochondria have been based on the finding that paromomycin at 1000 μg/ml inhibits mitochondrial respiration when the mitochondrial membrane has been sufficiently damaged. Under conditions where membrane damage permits free access of paromomycin, neither this antibiotic nor erythromycin nor lincomycin has a specific inhibitory effect on protein synthesis. The possibility is discussed that the evolution of the ribosome from the bacterial ribosome through the yeast mitochondrial ribosome to the mammalian mitochondrial “miniribosome” may be expressed in the loss of certain antibiotic-binding proteins of the protein-synthesizing system.

The absorption, and the biliary and urinary excretion of radioactivity was studied in biliary fistulated rats and guinea-pigs given 35S-sporidesmin in an attempt to determine the factors responsible for the species difference in sensitivity to the mycotoxin sporidesmin. The absorption and excretion of radioactivity by both species was similar in both magnitude and rate. The enterohepatic circulation of sporidesmin or of its metabolites is reported. It is suggested that differences in the species' sensitivity to sporidesmin must lie in variations in sensitivity at the enzyme level, rather than in differences in absorption and excretion, leading to differing toxin concentrations within the susceptible tissues.