Rat model of distraction osteogenesis

Prior studies of distraction osteogenesis in dog and rabbit models have shown predominantly intramembranous bone formation. Other models of fracture healing normally display mixtures of both endochondral and intramembranous bone formation. We have established a rat model of tibial lengthening that reliably reproduces the pattern of zonal osteogenesis previously observed in dog and rabbit models. A distraction rate of 0.25 mm twice a day with a 0-day latency period produced intramembranous bone with zones of progressive mineralization from collagen. With this protocol, rats bridged the distraction gap with a 25% increase in the tibial bone length. After 20 days of distraction and 50 days of consolidation, the three-point bending stiffness, as a percentage of the contralateral control, reached a level equivalent to that measured in the canine model for a 15% lengthening (28-day distraction and 84-day consolidation). Radiodensitometric analysis of the regenerate bones measured 97% of the unaffected contralateral tibial densities, and mineral analyses demonstrated that calcium and phosphorus levels in the regenerate bone reached 78% of contralateral tibial levels by day 70. We concluded that a rat model of distraction ostegenesis will be useful for a wide range of studies involving rapid intramembranous bone formation.     

Predictors of employment in substance-using male and female welfare recipients

This study examined predictors of employment among substance-using men and women enrolled in welfare-to-work programs. Participants were 394 welfare applicants assigned to either coordinated care management or usual care for treatment services and job training and followed up for 1 year to track employment outcomes. Common barriers to work were assessed at baseline in four key domains: disabilities, situational barriers, labor capital, and motivation. Results indicated substantial gender differences in the number and profile of work barriers. Among men, work experience and job motivation were the only significant predictors of employment; among women, multiple factors from each barrier domain predicted job acquisition even when controlling for all other significant predictors. Findings suggest that welfare-to-work programs should emphasize job training and job seeking during the early stages of welfare interventions for men and for many women.     

The importance of supporting nursing colleagues on scope of practice issues

Although scope of practice issues contained in state statutes are often perceived as "tedious" by nurses, these issues are nonetheless important. This article cites a recent court case that demonstrates the importance of supporting nursing colleagues on these issues.     

Mortality among infants of black as compared with white college-educated parents.

BACKGROUND. In the United States, black infants are twice as likely to die as white infants; this difference reflects both black infants' higher rates of low birth weight and the higher mortality among black infants of normal birth weight. We studied mortality in infants born to college-educated parents in order to investigate this gap while controlling for sociodemographic variables. METHODS. We used the National Linked Birth and Infant Death Files for 1983 through 1985 to calculate infant mortality rates for children born to college-educated parents. The study population consisted of 865, 128 white infants and 42,230 black infants. A separate effect of birth weight was assessed by examining mortality rates before and after the exclusion of infants weighing less than 2500 g at birth (low-birth-weight infants). RESULTS. In this population, the infant mortality rate was 10.2 per 1000 live births for black infants and 5.4 per 1000 live births for white infants; the adjusted odds ratio for death among black infants was 1.82 (95 percent confidence interval, 1.64 to 2.01). The rate of low birth weight was more than twice as high among blacks (7 percent) as among whites (3 percent), although the mortality rate in this group was not higher among blacks than among whites. Black infants were three times as likely as white infants to die of causes attributable to perinatal events, including prematurity. They were no more likely to die of the sudden infant death syndrome. After the exclusion of low-birth-weight infants, the mortality rates for black and white infants were equal. CONCLUSIONS. In contrast to black infants in the general population, black infants born to college-educated parents have higher mortality rates than similar white infants only because of their higher rates of low birth weight. Black and white infants of normal birth weight have equivalent mortality rates.     

Chromogranin A: osmotically active fragments and their susceptibility to proteolysis during lysis of the bovine chromaffin granules

Osmotically active fragments of chromogranin A (Chr A) were studied in lysates from bovine chromaffin granules (CG) disrupted in the presence or absence of inhibitors of endogenous proteolytic activities. The effects of various methods of lysis were examined by micro-osmometry, PAGE-SDS electrophoretic techniques and immunoblots with polyclonal anti-Chr A sera. Osmotically active 'small' Chr A fragments (below 30 kDa) were conspicuous in lysates containing cocktails of leupeptin, pepstatin A, pHMB, PMSF and aprotinin. The osmotically inactive native Chr A in the 68-100 kDa range and the osmotically active fragments below 47 kDa were degraded in lysates at neutral or acid pH in the absence of inhibitors. However, degradation of the native Chr A and intermediates below 47 kDa could be prevented by extraction directly from intact CG, notably in cold or boiling distilled water. On the other hand, the main product after large-scale extraction of CG in 1 M acetic acid (pH 1.9, 100 degrees C) was a novel, osmotically active fragment (22 kDa), immunostaining only for the N-terminal sequence (Chr A1-40). The heat-stable fraction (Mr,n 23 kDa) exhibited concentration-independent colloid osmotic pressures even in the absence of phosphate, a property which may distinguish this N-terminal-containing fragment from the larger intermediates, probably containing the pancreastatin sequence, and other regions at the C-terminal side of the prohormone molecule. The functional roles of these osmotically active intermediates in the processing of Chr A are not yet known.     

Therapist Self-Report of Fidelity to Core Elements of Family Therapy for Adolescent Behavior Problems: Psychometrics of a Pragmatic Quality Indicator Tool

Therapist-report measures of evidence-based interventions have enormous potential utility as quality indicators in routine care; yet, few such tools have shown strong psychometric properties. This study describes reliability and validity characteristics of a therapist-report measure of family therapy techniques for treating adolescent conduct and substance use problems: Inventory of Therapy Techniques for Core Elements of Family Therapy (ITT-CEFT). Study participants included 31 staff therapists treating 68 adolescent clients in eight community-based mental health and substance use clinics. Therapists submitted ITT-CEFT checklists and companion audio recordings for 189 sessions. The ITT-CEFT contains 13 techniques identified as core elements of three manualized family therapy models that are empirically supported for the target group. Therapists also reported on their use of three motivational interventions, and independent observers coded the submitted recordings. ITT-CEFT factor validity was shown via confirmatory factor analyses of the tool’s theoretical structure. Derived modules were: Family Engagement (four items; Cronbach’s α?=?.72); Relational Orientation (five items; α?=?.74); and Interactional Change (four items; α?=?.66). Concurrent validity analyses showed fair-to-excellent therapist reliability compared to observer ratings (ICCs range .64–.75); they showed moderate therapist accuracy compared to observer mean scores, reflecting a tendency to overestimate delivery of the techniques. Discriminant validity analyses showed tool differentiation from motivational interventions. Results offer provisional evidence for the feasibility of using the therapist-report ITT-CEFT to anchor quality procedures for family therapy interventions in real-world settings.

Trial Registration: The parent clinical trial is registered at www.ClinicalTrials.gov, ID: NCT03342872 (registration date: 11.10.17).