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Background: Obesity is associated with chronic inflammation and is a risk factor for insufficient milk production. Inflammation-mediated suppression of LPL could inhibit mammary uptake of long-chain fatty acids (LCFAs; >16 carbons)., Objectives: In an ancillary case-control analysis, we investigated whether women with low milk production despite regular breast emptying have elevated inflammation and disrupted transfer of LCFAs from plasma into milk., Methods: Data and specimens from a low milk supply study and an exclusively breastfeeding control group were analyzed, with milk production measured by 24-h test-weighing at 2-10 wk postpartum. Low milk supply groups were defined as very low (VL; <300 mL/d; n = 23) or moderate (MOD; ≥300 mL/d; n = 20) milk production, and compared with controls (≥699 mL/d; n = 18). Serum and milk fatty acids (weight% of total) were measured by GC, serum and milk TNF-α by ELISA, and serum high-sensitivity C-reactive protein (hsCRP) by clinical analyzer. Group differences were assessed by linear regression models, chi-square exact tests, and Kruskal-Wallis nonparametric tests., Results: VL cases, as compared with MOD cases and controls, had higher prevalence of elevated serum hsCRP (>5 mg/L; 57%, 15%, and 22%, respectively; P = 0.004), detectable milk TNF-α (67%, 32%, and 33%, respectively; P = 0.04), and obesity (78%, 40%, and 22%, respectively; P = 0.003). VL cases had lower mean ± SD LCFAs in milk (60% ± 3%) than MOD cases (65% ± 4%) and controls (66% ± 5%) (P < 0.001). Milk and serum LCFAs were strongly correlated in controls (r = 0.82, P < 0.001), but not in the MOD (r = 0.25, P = 0.30) or VL (r = 0.20, P = 0.41) groups (Pint < 0.001)., Conclusions: Mothers with very low milk production have significantly higher obesity and inflammatory biomarkers, lower LCFAs in milk, and disrupted association between plasma and milk LCFAs. These data support the hypothesis that inflammation disrupts normal mammary gland fatty acid uptake. Further research should address impacts of inflammation and obesity on mammary fatty acid uptake for milk production., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Society for Nutrition.)

Background: A comprehensive approach to breastfeeding support requires elucidation of how metabolic health influences milk production. Objective: We compared metabolic health indicators in women with severely low milk output versus those with moderate/normal milk output using a case-control study design, with nested and external control groups. Design: Cases and nested controls were derived from women screened for a low milk supply trial, with cases defined as severely low milk output (<300 mL/24 hours), and nested controls defined as moderate/normal milk output (>300 mL/24 hours). In addition, we included an external control group of exclusively breastfeeding women. All were enrolled at 2-10 weeks postdelivery of a healthy term infant. Milk output and breast emptying frequency were recorded through test-weigh. Metabolic health variables included all components of the metabolic syndrome, homeostatic model assessment of insulin resistance (HOMA-IR), and diagnosis of gestational diabetes mellitus (GDM). Results: Maximum milk output, mL/24 hours, ranged as follows: 30-281 in cases ( n  = 18), 372-801 in nested controls ( n  = 12), and 661-915 in external controls ( n  = 12). Mean breast emptying frequency in cases was not significantly different from nested or external controls. All metabolic syndrome components and HOMA-IR were significantly worse in cases as compared with both nested and external control groups ( p  < 0.05). There was no significant difference between the nested and external control groups for these variables. GDM prevalence was 39%, 0%, and 8%, across cases, nested control, and external control groups, respectively (chi-square p -value = 0.02). Conclusion: Results from this small case-control study identify class 2+ obesity and poor metabolic health as strong risk factors for severely low milk production. These findings should be further validated in larger prospective cohort studies designed to identify individuals at risk for metabolically driven low milk supply. In addition, clinical and qualitative research studies aimed at improving patient-centered approaches to the management of persistent low milk supply are needed.

Background: Safety and reduction of errors during medication administration is a prominent focus in nursing and nursing education. Developing simulated medication administration experiences that include opportunities for nursing students to manage interruptions in a realistic environment can help improved critical thinking and reasoning for safe administration practices., Method: Sophomore nursing students voluntarily participated in a quality improvement project examining nursing management of interruptions during medication administration. Students observed medication administration activities for episodes of interruptions and conducted surveys in a real-time format that encouraged decision-making dialogue., Results: After the project, student learning outcomes included improved identification of interruptions, prioritization, critical reasoning skills, and development of management techniques for better safety., Conclusion: Incorporating real-world experiences that allow nursing students to identify and manage interruptions during medication administration foster development of critical thinking and interruption management techniques. [ J Nurs Educ . 2022;61(5):268-271.] .

Background: Flexible work-life policies for medical school faculty are necessary to support career progress, advancement, retention, and job satisfaction. Objective: Our objective was to perform a 10-year follow-up descriptive assessment of the availability of flexible work-life policies for faculty in medical schools in the Big Ten Conference. Design: In this descriptive study, a modified objective scoring system was used to evaluate the flexibility of faculty work-life policies at 13 medical schools in the Big Ten Conference. Policy information was obtained from institutional websites and verified with the human resources offices. Scores from the 2011 study and 2020 were compared. Results: Michigan State and Ohio State Universities offered the most flexible policies (score 17.75/22) with the Universities of Maryland and Minnesota following (score 16/22). The largest delta scores, indicating more flexible policies in the past decade, were at University of Minnesota (5.25) and University of Michigan (5). Policies for parental leave and part-time faculty varied widely. Most schools earned an additional point in the newly added category of "flexible scheduling and return-to-work policies." Nearly every institution reported dedicated lactation spaces and improved childcare options. Limitations : Limitations included missing policy data and interpretation bias in reviewing the policy websites, unavailable baseline data for schools that joined the Big Ten after the 2011 study, and unavailable baseline data for the additional category of return-to-work policies. Conclusions: While progress has been made, every institution should challenge themselves to review flexibility in work-life policies for faculty. It is important to advance a healthy competition with the goal to achieve more forward-thinking policies that improve retention, recruitment, and advancement of faculty. Big Ten institutions can continue to advance their policies by providing greater ease of access to options, further expansion of parental leave and childcare support, and offering more flexible policies for part-time faculty., Competing Interests: No competing financial interests exist., (© Emily A. Wagner et al., 2022; Published by Mary Ann Liebert, Inc.)

Nurses transitioning to care and novice-level nurses experience difficulty managing interruptions in the acute care setting, which can result in loss of attention and potential errors. Understanding better the characteristics surrounding interruptions will better guide staff development educators in designing management strategies as well as improving clinical reasoning that supports a culture of safety among staff and professional partners.

Native microbiota represent a potential resource for biocontrol of arthropod vectors. Ixodes scapularis is mostly inhabited by the endosymbiotic Rickettsia buchneri , but the composition of bacterial communities varies with life stage, fed status, and/or geographic location. We compared bacterial community diversity among I. scapularis populations sampled within a small geographic range in Central Pennsylvania. We collected and extracted DNA from ticks and sequenced amplicons of the eubacterial 16S rRNA gene from individuals and pooled samples. We then used taxon-specific PCR and/or qPCR to confirm the abundance or infection frequency of select pathogenic and symbiotic bacteria. Bacterial communities were more diverse in pools of males than females and the most abundant taxon was Rickettsia buchneri followed by Coxiellaceae (confirmed by sequencing as an unknown Rickettsiella species). High Rickettsiella titers in pools were likely due to a few heavily infected males. We determined that the infection frequency of Borrelia burgdorferi ranged from 20 to 75%. Titers of Anaplasma phagocytophilum were significantly different between sexes. Amplicon-based bacterial 16S sequencing is a powerful tool for establishing the baseline community diversity and focusing hypotheses for targeted experiments, but care should be taken not to overinterpret data based on too few individuals. We identified intracellular bacterial candidates that may be useful as targets for manipulation., Competing Interests: The authors declare no conflict of interest.

Objective: An efficient method for measuring maternal milk production is needed. Our objectives were to: (1) validate a milk production rate (MPR) protocol in exclusively breastfeeding mothers; (2) determine MPR change following 48 hours of increased breast emptying; (3) assess agreement between MPR and infant test-weighing; and (4) characterize MPR in early postpartum exclusively breastfeeding mothers. Materials and Methods: N  = 23 mothers emptied both breasts hourly over 3 hours (h0, h1, h2, and h3). We estimated steady-state MPR as mean (h2 and h3). Subset A mothers ( n  = 5) also completed MPR measurements after 48 hours of increased breast emptying. Subset B mothers ( n  = 16) also test-weighed for 48 hours. We used paired t -test to examine within-participant change in hourly milk yield and MPR; and we used Bland-Altman analysis to compare 24-hour milk production (g/24 hours) measured using test-weight versus MPR. Results are reported as mean ± standard deviation or (±95% limits of agreement). Results: Mothers were 54 ± 14 days postpartum. Paired difference in h3-h2 hourly milk yield was not significantly different ( p  > 0.05, 3 ± 10 g/hour). In Subset A ( n  = 5), MPR declined from 50 ± 13 to 43 ± 16 g/hour ( p  = 0.003) following 48 hours of increased breast emptying. In Study B ( n  = 16), mean infant test-weighed intake (TW) was 717 ± 119 g/24 hours, and mean MPR was 1,085 ± 300 g/24 hours. Mean difference (MPR-test-weigh) and mean ratio (MPR/test-weigh) significantly increased as MPR increased ( p  < 0.05). For infants with adequate weight gain (>20 g/24 hours, n  = 12), mean MPR = 48 ± 12 g/hour (range, 35-78 g/hour). Conclusion: MPR is a valid measure of current maternal milk production capacity, but is not accurate for evaluating infant intake in exclusively breastfeeding dyads.

In acute care settings, registered nurses need to delegate effectively to unlicensed assistive personnel to provide safe care. This project explored the impact of improved delegation-communication between nurses and unlicensed assistive personnel on pressure injury rates, falls, patient satisfaction, and delegation practices. Findings revealed a tendency for nurses to delay the decision to delegate. However, nurses' ability to explain performance appraisals, facilitate clearer communication, and seek feedback improved. Patient outcomes revealed decreased falls and improved patient satisfaction.

We report that, among exclusively breastfeeding mothers at day 7 postpartum, those with milk supply concerns were significantly more likely to exhibit biochemical evidence of less progress toward mature lactation (elevated ratio of breast milk sodium to potassium concentration). Furthermore, an elevated ratio of breast milk sodium to potassium concentration was predictive of early weaning., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Amniotic fluid (AF) is a proximal fluid to the fetus containing higher amounts of cell-free fetal RNA/DNA than maternal serum, thereby making it a promising source for identifying novel biomarkers that predict fetal development and organ maturation. Our aim was to compare AF transcriptomic profiles at different time points in pregnancy to demonstrate unique genetic signatures that would serve as potential biomarkers indicative of fetal maturation., Methods: We isolated AF RNA from 16 women at different time points in pregnancy: 4 from 18 to 24 weeks, 6 from 34 to 36 weeks, and 6 from 39 to 40 weeks. RNA-sequencing was performed on cell-free RNA. Gene expression and splicing analyses were performed in conjunction with cell-type and pathway predictions., Results: Sample-level analysis at different time points in pregnancy demonstrated a strong correlation with cell types found in the intrauterine environment and fetal respiratory, digestive and external barrier tissues of the fetus, using high-confidence cellular molecular markers. While some RNAs and splice variants were present throughout pregnancy, many transcripts were uniquely expressed at different time points in pregnancy and associated with distinct neonatal co-morbidities (respiratory distress and gavage feeding), indicating fetal immaturity., Conclusion: The AF transcriptome exhibits unique cell/organ-selective expression patterns at different time points in pregnancy that can potentially identify fetal organ maturity and predict neonatal morbidity. Developing novel biomarkers indicative of the maturation of multiple organ systems can improve upon our current methods of fetal maturity testing which focus solely on the lung, and will better inform obstetrical decisions regarding delivery timing.

Although numerous fields continue to advance research toward various areas of health prevention, communication researchers have yet to examine fully the link between communication and health improvement. This is particularly true of those studying the intersections of family and health communication--unfortunate, given that family members serve as primary socialization agents in health attitudes and behaviors. Using the example of obesity-related health behaviors, the following essay advances the argument that continued research aimed at understanding the intersection of health and families' communicative influence may help to illuminate the nature, causes, and redress to health issues that are correlated with individual health practices. This is accomplished by (a) reviewing contributions and limitations of pioneering studies in (family) health literature and (b) offering three key research areas for health communication exploration that will move scholars toward communication-based solutions (e.g., family-level communication health interventions).

Objective: To evaluate in-hospital formula supplementation among first-time mothers who intended to exclusively breastfeed and determined if in-hospital formula supplementation shortens breastfeeding duration after adjusting for breastfeeding intention., Study Design: We assessed strength of breastfeeding intentions prenatally in a diverse cohort of expectant primiparae and followed infant feeding practices through day 60. Among mothers planning to exclusively breastfeed their healthy term infants for ≥1 week, we determined predictors, reasons, and characteristics of in-hospital formula supplementation, and calculated the intention-adjusted relative risk (ARR) of not fully breastfeeding days 30-60 and breastfeeding cessation by day 60 with in-hospital formula supplementation (n = 393)., Results: Two hundred ten (53%) infants were exclusively breastfed during the maternity stay and 183 (47%) received in-hospital formula supplementation. The most prevalent reasons mothers cited for in-hospital formula supplementation were: perceived insufficient milk supply (18%), signs of inadequate intake (16%), and poor latch or breastfeeding (14%). Prevalence of not fully breastfeeding days 30-60 was 67.8% vs. 36.7%, ARR 1.8 (95% CI, 1.4-2.3), in-hospital formula supplementation vs exclusively breastfed groups, respectively, and breastfeeding cessation by day 60 was 32.8% vs. 10.5%, ARR 2.7 (95% CI, 1.7-4.5). Odds of both adverse outcomes increased with more in-hospital formula supplementation feeds (not fully breastfeeding days 30-60, P = .003 and breastfeeding cessation, P = .011)., Conclusions: Among women intending to exclusively breastfeed, in-hospital formula supplementation was associated with a nearly 2-fold greater risk of not fully breastfeeding days 30-60 and a nearly 3-fold risk of breastfeeding cessation by day 60, even after adjusting for strength of breastfeeding intentions. Strategies should be sought to avoid unnecessary in-hospital formula supplementation and to support breastfeeding when in-hospital formula supplementation is unavoidable., (Copyright © 2014 Elsevier Inc. All rights reserved.)

This article reports the outcomes of a kinesthetic learning strategy used during a cardiac lecture to engage students and to improve the use of classroom-acquired knowledge in today's challenging clinical settings. Nurse educators are constantly faced with finding new ways to engage students, stimulate critical thinking, and improve clinical application in a rapidly changing and complex health care system. Educators who deviate from the traditional pedagogy of didactic, content-driven teaching to a concept-based, student-centered approach using active and kinesthetic learning activities can enhance engagement and improve clinical problem solving, communication skills, and critical thinking to provide graduates with the tools necessary to be successful. The goals of this learning activity were to decrease the well-known classroom-clinical gap by enhancing engagement, providing deeper understanding of cardiac function and disorders, enhancing critical thinking, and improving clinical application., (Copyright 2014, SLACK Incorporated.)

Objective: We characterized breastfeeding concerns from open-text maternal responses and determined their association with stopping breastfeeding by 60 days (stopping breastfeeding) and feeding any formula between 30 and 60 days (formula use)., Methods: We assessed breastfeeding support, intentions, and concerns in 532 expectant primiparas and conducted follow-up interviews at 0, 3, 7, 14, 30, and 60 days postpartum. We calculated adjusted relative risk (ARR) and adjusted population attributable risk (PAR) for feeding outcomes by concern category and day, adjusted for feeding intentions and education., Results: In 2946 interviews, 4179 breastfeeding concerns were reported, comprising 49 subcategories and 9 main categories. Ninety-two percent of participants reported ≥ 1 concern at day 3, with the most predominant being difficulty with infant feeding at breast (52%), breastfeeding pain (44%), and milk quantity (40%). Concerns at any postpartum interview were significantly associated with increased risk of stopping breastfeeding and formula use, with peak ARR at day 3 (eg, stopping breastfeeding ARR [95% confidence interval] = 9.2 [3.0-infinity]). The concerns yielding the largest adjusted PAR for stopping breastfeeding were day 7 "infant feeding difficulty" (adjusted PAR = 32%) and day 14 "milk quantity" (adjusted PAR = 23%)., Conclusions: Breastfeeding concerns are highly prevalent and associated with stopping breastfeeding. Priority should be given to developing strategies for lowering the overall occurrence of breastfeeding concerns and resolving, in particular, infant feeding and milk quantity concerns occurring within the first 14 days postpartum.

This study explored associations among family communication patterns (conversation and conformity orientations), health-specific communication variables, health attitudes, and health behaviors in a sample of 433 family dyads (N = 866). As expected, results of multilevel models revealed that individuals' health attitudes were strongly associated with their self-reported health behaviors. Findings also suggested that perceived confirmation from a family member during health-specific conversations (a) directly influenced health attitudes, (b) partially accounted for the positive relationship between family conversation orientation and health attitudes, and (c) partially accounted for the inverse relationship between family conformity orientation and health attitudes. Similarly, frequency of health-specific communication (a) directly influenced health attitudes, (b) partially accounted for the positive relationship between family conversation orientation and health attitudes, and (c) directly associated with health behaviors. Results from an actor-partner interdependence model (APIM) supported the aforementioned within-person association between a person's own health attitudes and health behaviors, as well as a positive relationship between young adults' health attitudes and their influential family member's health behaviors. Implications of these findings are discussed as they relate to theory and obesity prevention.

Mouse Xin-alpha (mXin-alpha) encodes a Xin repeat-containing, actin-binding protein localized to the intercalated disc (ICD). Ablation of mXin-alpha progressively leads to disrupted ICD structure, cardiac hypertrophy and cardiomyopathy with conduction defects during adulthood. Such conduction defects could be due to ICD structural defects and/or cell electrophysiological property changes. Here, we showed that despite the normal ICD structure, juvenile mXina-null cardiomyocytes (from 3~4-week-old mice) exhibited a significant reduction in the transient outward K+ current (ITO), similar to adult mutant cells. Juvenile but not adult mutant cardiomyocytes also had a significant reduction in the delayed rectifier K+ current. In contrast, the mutant adult ventricular myocytes had a significant reduction in the inward rectifier K+ current (IK1) on hyperpolarization. These together could account for the prolongation of action potential duration (APD) and the ease of developing early afterdepolarization observed in juvenile mXin-alpha-null cells. Interestingly, juvenile mXin-alpha-null cardiomyocytes had a notable decrease in the amplitude of intracellular Ca2+ transient and no change in the L-type Ca2+ current, suggesting that the prolonged APD did not promote an increase in intracellular Ca2+ for cardiac hypertrophy. Juvenile mXin-alpha-null ventricles had reduced levels of membrane-associated Kv channel interacting protein 2, an auxiliary subunit of ITO, and filamin, an actin cross-linking protein. We further showed that mXin-alpha interacted with both proteins, providing a novel mechanism for ITO surface expression.

Rationale: The Xin repeat-containing proteins mXinalpha and mXinbeta localize to the intercalated disc of mouse heart and are implicated in cardiac development and function. The mXinalpha directly interacts with beta-catenin, p120-catenin, and actin filaments. Ablation of mXinalpha results in adult late-onset cardiomyopathy with conduction defects. An upregulation of the mXinbeta in mXinalpha-deficient hearts suggests a partial compensation., Objective: The essential roles of mXinbeta in cardiac development and intercalated disc maturation were investigated., Methods and Results: Ablation of mXinbeta led to abnormal heart shape, ventricular septal defects, severe growth retardation, and postnatal lethality with no upregulation of the mXinalpha. Postnatal upregulation of mXinbeta in wild-type hearts, as well as altered apoptosis and proliferation in mXinbeta-null hearts, suggests that mXinbeta is required for postnatal heart remodeling. The mXinbeta-null hearts exhibited a misorganized myocardium as detected by histological and electron microscopic studies and an impaired diastolic function, as suggested by echocardiography and a delay in switching off the slow skeletal troponin I. Loss of mXinbeta resulted in the failure of forming mature intercalated discs and the mislocalization of mXinalpha and N-cadherin. The mXinbeta-null hearts showed upregulation of active Stat3 (signal transducer and activator of transcription 3) and downregulation of the activities of Rac1, insulin-like growth factor 1 receptor, protein kinase B, and extracellular signal-regulated kinases 1 and 2., Conclusions: These findings identify not only an essential role of mXinbeta in the intercalated disc maturation but also mechanisms of mXinbeta modulating N-cadherin-mediated adhesion signaling and its crosstalk signaling for postnatal heart growth and animal survival.

Targeted deletion of mXinalpha results in cardiac hypertrophy and cardiomyopathy with conduction defects (Gustafson-Wagner, E., Sinn, H. W., Chen, Y.-L., Wang, D.-Z., Reiter, R. S., Lin, J. L.-C., Yang, B., Williamson, R. A., Chen, J. N., Lin, C.-I., and Lin, J. J.-C. (2007) Am. J. Physiol. 293, H2680-H2692). To understand the underlying mechanisms leading to such cardiac defects, the functional domains of mXinalpha and its interacting proteins were investigated. Interaction studies using co-immunoprecipitation, pull-down, and yeast two-hybrid assays revealed that mXinalpha directly interacts with beta-catenin. The beta-catenin-binding site on mXinalpha was mapped to amino acids 535-636, which overlaps with the known actin-binding domains composed of the Xin repeats. The overlapping nature of these domains provides insight into the molecular mechanism for mXinalpha localization and function. Purified recombinant glutathione S-transferase- or His-tagged mXinalpha proteins are capable of binding and bundling actin filaments, as determined by co-sedimentation and electron microscopic studies. The binding to actin was saturated at an approximate stoichiometry of nine actin monomers to one mXinalpha. A stronger interaction was observed between mXinalpha C-terminal deletion and actin as compared with the interaction between full-length mXinalpha and actin. Furthermore, force expression of green fluorescent protein fused to an mXinalpha C-terminal deletion in cultured cells showed greater stress fiber localization compared with force-expressed GFP-mXinalpha. These results suggest a model whereby the C terminus of mXinalpha may prevent the full-length molecule from binding to actin, until the beta-catenin-binding domain is occupied by beta-catenin. The binding of mXinalpha to beta-catenin at the adherens junction would then facilitate actin binding. In support of this model, we found that the actin binding and bundling activity of mXinalpha was enhanced in the presence of beta-catenin.

The intercalated disk protein Xin was originally discovered in chicken striated muscle and implicated in cardiac morphogenesis. In the mouse, there are two homologous genes, mXinalpha and mXinbeta. The human homolog of mXinalpha, Cmya1, maps to chromosomal region 3p21.2-21.3, near a dilated cardiomyopathy with conduction defect-2 locus. Here we report that mXinalpha-null mouse hearts are hypertrophied and exhibit fibrosis, indicative of cardiomyopathy. A significant upregulation of mXinbeta likely provides partial compensation and accounts for the viability of the mXinalpha-null mice. Ultrastructural studies of mXinalpha-null mouse hearts reveal intercalated disk disruption and myofilament disarray. In mXinalpha-null mice, there is a significant decrease in the expression level of p120-catenin, beta-catenin, N-cadherin, and desmoplakin, which could compromise the integrity of the intercalated disks and functionally weaken adhesion, leading to cardiac defects. Additionally, altered localization and decreased expression of connexin 43 are observed in the mXinalpha-null mouse heart, which, together with previously observed abnormal electrophysiological properties of mXinalpha-deficient mouse ventricular myocytes, could potentially lead to conduction defects. Indeed, ECG recordings on isolated, perfused hearts (Langendorff preparations) show a significantly prolonged QT interval in mXinalpha-deficient hearts. Thus mXinalpha functions in regulating the hypertrophic response and maintaining the structural integrity of the intercalated disk in normal mice, likely through its association with adherens junctional components and actin cytoskeleton. The mXinalpha-knockout mouse line provides a novel model of cardiac hypertrophy and cardiomyopathy with conduction defects.

There is conflicting evidence regarding the effects of high protein intake on kidney health, especially as it relates to age. We investigated the short-term effects of a high-protein diet on kidney function and systemic acid-base homeostasis in older compared to younger adults. The subjects were healthy men and women either between the ages of 25 and 40 years (n=12) or 55 and 70 years (n=10). They underwent a two-period crossover trial with each period consisting of 2 weeks of usual diet followed by a 1-week experimental diet. During the experimental diet period subjects consumed metabolic meals that provided either low protein content (0.5 g protein/kg/day) or high protein content (2.0 g protein/kg/day). Outcome measures included blood and urine markers of renal function and acid-base balance. An analysis of variance was used to assess differences between age groups with respect to experimental diet. The older group, mainly women, showed an increase in glomerular filtration rate after the high-protein compared to low-protein diet; the younger group did not. Urinary pH was significantly lower, and ammonium excretion was significantly higher after the high-protein diet in both age groups, but neither group developed a clinically detectable acidosis after the week of receiving a high-protein diet.

To understand how cardiac gene expression is regulated, the identification and characterization of cis-regulatory elements and their trans-acting factors by gel mobility shift assay (GMSA) or gel retardation assay are essential and common steps. In addition to providing a general protocol for GMSA, this chapter describes some applications of this assay to characterize cardiac-specific and ubiquitous trans-acting factors bound to regulatory elements [novel TCTG(G/C) direct repeat and A/T-rich region] of the rat cardiac troponin T promoter. In GMSA, the specificity of the binding of trans-acting factor to labeled DNA probe should be verified by the addition of unlabeled probe in the reaction mixture. The migratory property of DNA-protein complexes formed by protein extracts prepared from different tissues can be compared to determine the tissue specificity of trans-acting factors. GMSA, coupled with specific antibody to trans-acting factor (antibody supershift assay), is used to identify proteins present in the DNA-protein complex. The gel-shift competition assay with an unlabeled probe containing a slightly different sequence is a powerful technique used to assess the sequence specificity and relative binding affinity of a DNA-protein interaction. GMSA with SDS-PAGE fractionated proteins allows for the determination of the apparent molecular mass of bound trans-acting factor.

Xin was first cloned using differential mRNA display from the developing chicken heart. Chick Xin (cXin) participates in a BMP-Nkx2.5-MEF2C pathway to regulating cardiac morphogenesis. Through subsequent EST database searches and cDNA cloning, two mouse Xin genes, mXinα and mXinβ were identified and cloned. The human homologue of mXinα (named Cmya1) was mapped to chromosome 3p21.2-p21.3 by radiation hybrid analysis and recently to 3p22.2 by DNA sequencing, which is near the loci for a dilated cardiomyopathy with conduction defect-2 and arrhythmogenic right ventricular dysplasia-5. The predicted human homologue of mXinβ (named Cmya3) was mapped to chromosome 2q24.3 by DNA sequencing. Predicted Xin proteins all contain a novel 16-amino acid repeating unit (Xin repeat), a putative DNA binding domain and nuclear localization signal, as well as a proline-rich region. All three Xin genes from chick and mouse have a similar tissue expression profile, which is restricted to striated muscle. The expression of mXinα in Nkx2.5 or MEF2C knockout mouse embryos was drastically reduced, suggesting that mXinα is a downstream target of the Nkx2.5 and MEF2C transcription factors. On the other hand, the expression of mXin was up-regulated when mice were subjected to pressure overload-induced cardiac hypertrophy. Xin protein co-localizes with N-cadherin and β-catenin throughout mouse embryogenesis and into adulthood. Furthermore, mXinα appears to interact directly with β-catenin. The Xin repeats bind to actin filaments and may also organize microfilaments into networks. These results may suggest that Xin acts by integrating adhesion, by organizing actin filament arrangement at the insertion sites, and by regulating Wnt/β-catenin-and N-cadherin-mediated signaling pathways required for cardiac development and cardiac function.

Objectives: The purpose of this study is to assess training in Pediatric and Adolescent Gynecology (PAG) at the Obstetrics and Gynecology (OB/GYN) resident level., Setting: Two large Michigan programs were studied: a university-based, inner-city program, and a suburban, community-based program. Seventy-one questionnaires were distributed to the residents, and descriptive and inferential analysis of answers to demographic, training, attitude, and knowledge-based questions regarding PAG was performed., Results: Sixty-one questionnaires were returned, a response rate of 86%. The majority of respondents reported no PAG rotations or clinics and recalled limited didactic sessions with only 0-2 lectures. Ninety-eight percent of university residents and 94% of community residents requested more PAG training. Comfort levels about PAG issues were assessed on a 5 point scale (1 = low, 5 = high comfort); university residents scored 3.7 with pediatric patients and 4.4 with adolescents, and community residents scored 4.0 with the pediatric age group and 4.3 with adolescents. However, both groups responded with familiarity to knowledge based questions only 61% of the time., Conclusions: OB/GYN residents in both academic and community programs report little experience and scant training in PAG but express interest in obtaining the skills and information needed. It is concerning that residents lack the basic knowledge that is required for the routine daily care of this patient population. More emphasis needs to be placed on these issues in OB/GYN residency training programs.

Magnetic resonance imaging (MRI) and positron emission tomography (PET) with fluorodeoxyglucose were used to study the size and shape of the corpus callosum in 20 patients with unipolar depressive disorder and 16 normal controls. An automated algorithm outlined the corpus callosum and divided it into quarters. The anterior and posterior quarters of the corpus callosum were larger in depressed patients than in controls, findings similar to most earlier MRI studies of the corpus callosum in schizophrenics. The patient-normal difference was more marked in females than in males. PET glucose metabolic values were higher in patients with thinner or smaller callosums. The presence of marked sex differences makes future larger studies controlling body size and age important.

These authors suggest simplification of the technic by reducing the lactose content by addition of gentian violet, also Pasteurization in place of autoclaving. The announced value of gentian violet for preliminary enrichment of colon cultures is sustained, with cleaner plates and readier identification of colonies. Gentian violet has also advantages in ensuring keeping qualities in the broth.