Life-Space Mobility, Transportation, and the Companionship Network of Members of a Hispanic Senior Center.

OBJECTIVES: Companions (i.e., friends who spend time together) are important for the well-being of older adults. Senior centers in the United States are places for older adults to participate in group activities and form and maintain companionships. However, differences in mobility and transportation may affect the ability of older adults to leverage senior center activities into actual companionships. METHODS: This social network analysis was conducted to characterize the companionship network among members of a senior center in relation to their life-space mobility and transportation resources. An exponential random graph model was estimated to identify mobility- and transportation-related correlates of the likelihood of a companionship tie among senior center members (N = 42). RESULTS: Members had an average of 2 companionships with one another (M = 2.2, SD = 2.7). Companionships were more likely for members with greater life-space mobility (p = .009), who attended the senior center more frequently (p = .004), with automobile ownership in their households (p = .034), and who were not transportation cost-burdened (i.e., spent less than 15% of their income on transportation, p = .005). Demographic characteristics, limitations on instrumental activities of daily living, and being at risk for depression were not significantly associated with the likelihood of companionships. DISCUSSION: These findings extend previous knowledge of the role of life-space mobility and transportation in supporting general social participation for older adults to include the importance of transportation and mobility for having companions within a senior center.

Beyond "Disconnected Youth": Characterizing Developmental Heterogeneity in School or Work Connections During Emerging Adulthood.

Prior research on disconnected youth has defined connectedness to school or work during emerging adulthood as an either/or outcome, conflicting with research on emerging adulthood, which suggests varied, individualized pathways. This study used a growth mixture model method with data from the Panel Study of Income Dynamics Transition into Adulthood Supplement to elucidate developmental heterogeneity in connectedness to school or work during emerging adulthood (n = 1,977). Results indicated distinct subgroups of connectedness to school or work with additional variation within groups. Racialized group and parenting status differentiated between being fully connected or not but did not explain differences among those with less consistent connectedness. Policy implications include that the timing and duration of policies targeting disconnected youth may be missing a substantial minority of young people. Re-thinking supports for disconnected youth can be further informed by future research focused on examining factors related to individual differences in the timing and nature of connectedness to school or work.

Cesarean effects on adolescents' birth experiences: counterfactual analysis

Abstract Introduction The birth experience of adolescents is understudied even though they are a particularly vulnerable population to experience a negative birth event, given that they exhibit many known risk factors. Objective To ascertain whether a cesarean birth mediates the impact of infant complications on the birth experience of adolescent mothers. Methods Using a secondary analysis of data collected from 303 postpartum adolescents previously evaluated for depression and post-traumatic stress, we employed counterfactual causal analysis to determine if delivery type mediated the birth experience at different levels of depression. Noted limitations pertain to methodological assumptions and computational feasibility as well as potential sample bias. Results We found that the mediating effect of delivery mode depended on the adolescent's depression level as well as on the specific operationalization of the birth experience. At low levels of depression, the odds of a negative birth appraisal were reduced by around 30% when operationalized as a single item subjective rating. In contrast, at high levels of depression, the odds of a negative birth experience increased by 80% when operationalized as an Impact of Event Scale (IES) subconstruct. Conclusion Depression level plays a pivotal role in moderating how delivery mode mediates the birth experience. The direction of impact also depends on how the birth experience is operationalized.

Cesarean effects on adolescents' birth experiences: counterfactual analysis.

INTRODUCTION: The birth experience of adolescents is understudied even though they are a particularly vulnerable population to experience a negative birth event, given that they exhibit many known risk factors. OBJECTIVE: To ascertain whether a cesarean birth mediates the impact of infant complications on the birth experience of adolescent mothers. METHODS: Using a secondary analysis of data collected from 303 postpartum adolescents previously evaluated for depression and post-traumatic stress, we employed counterfactual causal analysis to determine if delivery type mediated the birth experience at different levels of depression. Noted limitations pertain to methodological assumptions and computational feasibility as well as potential sample bias. RESULTS: We found that the mediating effect of delivery mode depended on the adolescent's depression level as well as on the specific operationalization of the birth experience. At low levels of depression, the odds of a negative birth appraisal were reduced by around 30% when operationalized as a single item subjective rating. In contrast, at high levels of depression, the odds of a negative birth experience increased by 80% when operationalized as an Impact of Event Scale (IES) subconstruct. CONCLUSION: Depression level plays a pivotal role in moderating how delivery mode mediates the birth experience. The direction of impact also depends on how the birth experience is operationalized.

Measuring Adolescent Birth Trauma: Development, Adaptation, and Evaluation of the Psychometric Properties for the Childbirth Trauma Index.

BACKGROUND AND PURPOSE: Childbirth can have negative consequences; however, measurement tools to assess this event are limited; and none consider the adolescent's birth. This study assessed the psychometric properties of the childbirth trauma index (CTI). METHODS: Construct validity and reliability of the CTI was assessed via a field test involving 160 adolescents 3 days postpartum. RESULTS: A modified 8-item version of the original CTI exhibited acceptable construct validity and reliability criteria. The CTI was found to link with birth appraisal, but not subjective distress measurements. CONCLUSIONS: The CTI may be a more robust means of assessing birth appraisal than use of single-item measures. Recommendations for practice suggest use of the modified CTI to assess birth appraisal, or use in combination with single-item rating scales.

Predicting posttraumatic stress and depression symptoms among adolescents in the extended postpartum period.

BACKGROUND: Adolescent childbirth continues as a public health concern, and investigation of postpartum posttraumatic stress symptoms (PTSS) and depression is important to inform future research and practice. Longitudinal studies exploring PTSS alone or in combination with depression are non-existent for postpartum adolescent populations. This study aimed to identify stress/PTSS and depression symptoms at 72 hours and three, six, and nine months postpartum, and determine if symptoms at each time point predicted later symptoms. METHODS: A convenience sample of 303 adolescents 13-19 years of age were recruited from two postpartum units of one, large, public hospital. The Impact of Event Scale and the Edinburgh Postpartum Depression Inventory provided a screen of symptoms for stress/PTSS and depression at all time points. A lagged autoregressive model was developed to assess the predictive power of symptoms at each time point to the next across the extended postpartum period. RESULTS: About 30% of adolescents displayed early symptoms; 20% showed symptoms at the final time point. Early symptoms did not predict symptoms at 3 months; yet, symptoms at 3 months predicted symptoms at 6-9 months. LIMITATIONS: Attrition at final time points necessitated pooled data. Adolescents were primarily older, Hispanics, and recruited from one public hospital decreasing demographic representation. Use of screening tools prevented diagnostic outcomes. Unknown stressors occurring before and after pregnancy or birth may have influenced final outcomes. CONCLUSIONS: Early symptoms were common and 3 month symptoms predicted later symptoms. For at risk adolescents, a plan for follow-up beyond hospital discharge is recommended.

A Model to Predict Birth Stress in Adolescents Within 72 Hours of Childbirth.

An organizing framework for understanding adolescent birth stress in immediate postpartum does not exist. Researchers evaluated adolescent birth stress within 72 hours postpartum via a modification of Slade's conceptual model of risk factors for posttraumatic stress (PTS). Birth stress was defined by negative birth appraisal and subjective distress. Precipitating factors pain management, partner presence, and delivery type, plus maintaining factor infant complications, predicted negative birth appraisal. Predisposing factors depression and prior trauma predicted subjective distress. Findings support utility of Slade's modified model of PTS risk factors for identification of adolescent early birth stress and generate nursing practice and research implications.

Assimilation efficiency of sediment-bound PCBs ingested by fish impacted by strong sorption.

Uptake of polychlorinated biphenyls (PCBs) by fish is controlled by the bioavailability of ingested PCBs in the gut and the freely dissolved concentration in the water moving across the gills. The prediction of bioaccumulation in fish relies on models that account for these exposure routes; however, these models typically do not account for incidental ingestion of sediment by fish, which is not well studied. The literature values for the PCB assimilation efficiency in the gut have been reported for compounds in food matrices and not associated with sediment particles. It is also unclear how mitigation strategies that alter PCB bioavailability in sediments affect predictions made by the bioaccumulation models when sediment ingestion is involved. To test the bioavailability of PCBs from treated and untreated sediments, dietary assimilation efficiencies were measured for 16 PCB congeners in mummichogs (Fundulus heteroclitus) that were fed 4 experimental diets. Diets consisted of PCB-spiked earthworms, spiked untreated sediment mixed with earthworms, spiked activated carbon-treated sediment mixed with earthworms, and spiked activated carbon mixed with earthworms. Assimilation efficiencies were determined by calculating the ratio of PCB mass in the fish tissue to the PCB mass in the food after a pulse feeding experiment. Assimilation efficiencies of PCBs associated with earthworm diet were similar to the values reported in the literature. Fish that were fed the PCB-spiked untreated sediment and activated carbon particles exhibited the highest and lowest assimilation efficiencies, respectively, over a wide KOW range. Assimilation efficiencies of sediment-bound PCBs were significantly reduced (31-93% reduction for different congeners) after amendment with activated carbon. The present study indicates that assimilation of PCBs can be reduced by sorption to black carbon. Environ Toxicol Chem 2017;36:3480-3488. © 2017 SETAC.

Fingerprinting 2,3,7,8-tetrachlorodibenzodioxin contamination within the lower Passaic River.

The lower Passaic River is an operable unit of the Diamond Alkali Superfund site at 80 and 120 Lister Avenue in Newark, New Jersey, USA. Between 1948 and 1969, the Diamond Shamrock Chemicals Company and its predecessors manufactured chemicals such as pesticides and phenoxy herbicides, including 2,4,5-trichlorophenol, which is a precursor to 2,4,5-trichlorophenoxyacetic acid, one of the primary components used to make the military defoliant Agent Orange. A by-product of this manufacturing process was 2,3,7,8-tetrachlorodibenzodioxin (2,3,7,8-TCDD), and the site is considered the dominant source of 2,3,7,8-TCDD to the lower Passaic River and its environs. Several investigators have identified the ratio of 2,3,7,8-TCDD to total TCDD as a fingerprint for the site source. The present study presents data that establish polychlorinated dibenzodioxin/polychlorinated dibenzofuran (collectively, PCDD/F) congener and homolog fingerprints of soil and sump samples from the site. It then compares those fingerprints to the PCDD/F congener and homolog patterns in lower Passaic River sediments. The similarity of the patterns in lower Passaic River sediments to the site fingerprint indicates the site is the dominant source of the 2,3,7,8-TCDD in sediments within approximately the lower 14 miles of the lower Passaic River, excluding, for the purposes of the present discussion, Newark Bay. In addition, PCDD/F congener data indicate that the ratio of 1,3,7,8-TCDD to 2,3,7,8-TCDD is another marker of the site and corroborates the findings from the other fingerprints.

Pseudomonas aeruginosa inhibits endocytic recycling of CFTR in polarized human airway epithelial cells.

The most common mutation in the CFTR gene in individuals with cystic fibrosis (CF), DeltaF508, leads to the absence of CFTR Cl(-) channels in the apical plasma membrane, which in turn results in impairment of mucociliary clearance, the first line of defense against inhaled bacteria. Pseudomonas aeruginosa is particularly successful at colonizing and chronically infecting the lungs and is responsible for the majority of morbidity and mortality in patients with CF. Rescue of DeltaF508-CFTR by reduced temperature or chemical means reveals that the protein is at least partially functional as a Cl(-) channel. Thus current research efforts have focused on identification of drugs that restore the presence of CFTR in the apical membrane to alleviate the symptoms of CF. Because little is known about the effects of P. aeruginosa on CFTR in the apical membrane, whether P. aeruginosa will affect the efficacy of new drugs designed to restore the plasma membrane expression of CFTR is unknown. Accordingly, the objective of the present study was to determine whether P. aeruginosa affects CFTR-mediated Cl(-) secretion in polarized human airway epithelial cells. We report herein that a cell-free filtrate of P. aeruginosa reduced CFTR-mediated transepithelial Cl(-) secretion by inhibiting the endocytic recycling of CFTR and thus the number of WT-CFTR and DeltaF508-CFTR Cl(-) channels in the apical membrane in polarized human airway epithelial cells. These data suggest that chronic infection with P. aeruginosa may interfere with therapeutic strategies aimed at increasing the apical membrane expression of DeltaF508-CFTR.

A three-component regulatory system regulates biofilm maturation and type III secretion in Pseudomonas aeruginosa.

Biofilms are structured communities found associated with a wide range of surfaces. Here we report the identification of a three-component regulatory system required for biofilm maturation by Pseudomonas aeruginosa strain PA14. A transposon mutation that altered biofilm formation in a 96-well dish assay originally defined this locus, which is comprised of genes for a putative sensor histidine kinase and two response regulators and has been designated sadARS. Nonpolar mutations in any of the sadARS genes result in biofilms with an altered mature structure but do not confer defects in growth or early biofilm formation, swimming, or twitching motility. After 2 days of growth under flowing conditions, biofilms formed by the mutants are indistinguishable from those formed by the wild-type (WT) strain. However, by 5 days, mutant biofilms appear to be more homogeneous than the WT in that they fail to form large and distinct macrocolonies and show a drastic reduction in water channels. We propose that the sadARS three-component system is required for later events in biofilm formation on an abiotic surface. Semiquantitative reverse transcription-PCR analysis showed that there is no detectable change in expression of the sadARS genes when cells are grown in a planktonic culture versus a biofilm, indicating that this locus is not itself induced during or in response to biofilm formation. DNA microarray studies were used to identify downstream targets of the SadARS system. Among the genes regulated by the SadARS system are those required for type III secretion. Mutations in type III secretion genes result in strains with enhanced biofilm formation. We propose a possible mechanism for the role that the SadARS system plays in biofilm formation.

Progressive postnatal craniosynostosis and increased intracranial pressure.

Since its first description by Virchow in 1851, craniosynostosis has been known as a potentially serious condition resulting in premature fusion of skull sutures. Traditionally, craniosynostosis has been regarded as an event that occurs early in fetal development, resulting in a skull shape at birth that is determined by the suture or sutures involved. In recent years, a different form of craniosynostosis has been observed. Patients initially come to the attention of physicians because they exhibit midface hypoplasia or occasionally hypertelorism. The affected individuals all have a normal skull shape and open sutures in infancy but develop multiple-suture craniosynostosis postnatally, ultimately requiring surgical correction. These cases are significant because, although the patients do not initially display the physical manifestations of craniosynostosis, they frequently develop increased intracranial pressure, which can have devastating consequences. Unless these patients are recognized and vigilant follow-up monitoring is instituted at an early age, permanent impairment can result. A retrospective chart review study was conducted, and patients with multiple-suture craniosynostosis who developed symptoms of increased intracranial pressure were selected. The patients were divided into two groups, namely, those with normal sutures and/or head shape at birth (progressive craniosynostosis) (n = 15) and those with abnormal head shapes at birth (classic syndromic craniosynostosis) (n = 12). Clinical and radiological findings typically used to monitor the development of increased intracranial pressure were reviewed for both groups and compared. In addition, mutational analyses were performed. All patients with progressive postnatal craniosynostosis demonstrated clinical, radiological, or ophthalmological evidence of increased intracranial pressure, requiring skull expansion. Those patients displayed papilledema, anterior fontanelle bulge, and thumbprinting more often than did the patients with classic craniosynostosis. Thirteen of 15 patients were given the clinical diagnosis of Crouzon syndrome, which raises the question of whether such patients represent a subset of patients with this syndrome. Mutational analyses for the patients with progressive craniosynostosis demonstrated that, of 13 patients tested, 11 had mutations in exon 7 or 9 of FGFR2, which is a common site of mutations in Crouzon syndrome. The traditional indications of increased intracranial pressure used to monitor patients with classic craniosynostosis can be used to monitor patients with progressive postnatal craniosynostosis, particularly anterior fontanelle bulge, papilledema, and thumbprinting. It is thought that regular monitoring of these characteristics may lead to earlier diagnosis and allow for surgical intervention before the development of undesirable outcomes. It is important for clinicians to be aware of this group of patients, because any delay in diagnosis and treatment can result in severe consequences for the patients.

A custom mandibular distraction device for the rat.

In the last several years, the rat model has been used as a reliable means of studying distraction osteogenesis (DO). This model has several benefits, including lower cost, the availability of molecular reagents for the rat, and the ability to perform a large number of operations in a short time. We have recently developed an external device that is custom-made for the rat mandible and secured at the mandibular ramus. The device consists of a Leone (Florence, Italy) jackscrew distraction assembly (0.2 mm per one-quarter turn), 2 Luhr L-shaped 0.8-mm five-hole microplates, and four 0.8-mm x 3-mm microscrews (Stryker-Leibinger Corp., Kalamazoo, MI) for fixation. Additionally, there is a methylmethacrylate block that is placed on the lingual surface of the angle of the mandible to support the posterior screws. Sterile surgical technique was used, and the same two surgeons performed all operations. To date, we have operated on 153 Sprague-Dawley rats. The procedure has been well tolerated by the animals. We had 17 postoperative deaths (11% mortality), largely as a result of anesthetic complications. There were no wound infections or dehiscence. A mandible fracture was noted in 6 rats (4%), which occurred at the time of device placement. There were no device dislodgments. Postmortem examination showed the device to be well positioned in all rats, with good callous formation at the distraction site. The rats surpassed their preoperative weight after an average of 9.2 days. These results compare favorably with those of other models currently in use. We have developed a device that is currently being used in the study of DO in the rat mandible. Our device is small in size, does not require wide undermining for its placement, and has had a low incidence of device dislodgment or infection. This model has shown great reproducibility and thus should be effective in its application for the histologic and biochemical investigation of DO in the rat.