The impact of a clinical academic nurse researcher in critical care: A 1-year service review.

AIMS: To outline the activity and impact from implementing a clinical academic nurse researcher in a multi-centre critical care unit. DESIGN: A prospective exploratory activity audit informed by the Plan, Do, Study, Act framework. METHODS: Quantitative data on clinical academic activity, from 1 April 2023 to 31 March 2024, were collected in a Microsoft Excel © [2022, version 16.66.1] spreadsheet. Activity narratives were detailed in qualitative data and the impact categorized. RESULTS: A total of 1500 clinical academic activity hours were logged (accounting for annual leave entitlement and sickness). Of these, 973 h were directly categorized within clinical academic activity. Most frequently undertaken clinical academic activities were academic writing (17.6%), data collection/analysis (9.6%), grant and funding workup (6.8%), Intensive Care Unit service development (6.6%), clinical activity (5.2%) and local level capability and capacity (4.9%) and other supportive tasks such as administration, unscheduled meetings, critical planning time and peer support (38%). Improvements broadly mapped onto five healthcare improvement domains; organizational, process design, data optimization and utilization, evidenced-based practice, and patients/staff impact. CONCLUSIONS: Our data indicate system mechanisms afforded by the clinical academic role that have not been explored within the contemporary literature. A nursing clinical academic demonstrates impact across the broad organization whilst increasing the visibility of nursing work and the potential for system resilience. In conclusion, our service review underscores the transformative potential of clinical academics in shaping the future of healthcare. Utilizing their expertise and contributions paves the way for innovation, excellence and sustainability in patient care. IMPACT: This review has provided clarity about clinical academic activity of a nurse researcher during the first year. There is international impact of this work for both clinical academics who may be evaluating such roles and healthcare management developing similar roles locally. PATIENT AND PUBLIC CONTRIBUTION: No Patient or Public Contribution.

A randomized controlled trial of the impact of the Teen Council peer education program on youth development.

This paper presents results of an impact evaluation of Teen Council, a program that trains youth as peer educators. Teen Council is designed to help peer educators make healthy sexual and reproductive decisions, increase their confidence and abilities to educate their peers and inspire them to advocate for just sexual policies. The program's impact on these educators was evaluated using a randomized controlled trial. Over 5 years, interested high school students in seven states were randomly assigned to a study condition. An intent-to-treat framework using ordinary least square (OLS) regression was employed to measure program effects. Relative to control, Teen Council youth showed enhanced comfort with their own sexuality, greater comfort with and more frequent communication with parents about sexuality and more positive sexual health behaviors, including accessing reproductive health care and adopting more effective means of contraception. Teen Council youth also reported greater confidence in talking with peers about sexuality and more confidence in their civic engagement skills.

Experienced sitting-related problems and association with personal, lesion and wheelchair characteristics in persons with long-standing paraplegia and tetraplegia.

STUDY DESIGN: Cross-sectional study. OBJECTIVES: To describe experienced sitting-related health and stability problems among persons with paraplegia (PP) or tetraplegia (TP) and to investigate associations with personal, lesion and wheelchair characteristics as well as satisfaction with sitting posture. SETTING: Dutch community. METHODS: A self-report questionnaire on seating was developed and completed by wheelchair-users living with Spinal Cord Injury (SCI) for ≥10 years (N = 264). Sitting-related problems and satisfaction with sitting posture were compared between participants with PP and TP using Chi-square and t-tests. Logistic regression analyses were performed to investigate associated characteristics. RESULTS: Reported sitting-related problems comprised: sitting to be tiring (regularly to always) (33%), sitting to be painful (28%), pressure ulcers in the last three months (29%), instability while sitting (8%) and instability during reaching (33%). Except for instability during reaching, no differences in occurrence of sitting-problems were found between lesion-group. Persons with TP were more dissatisfied with their sitting posture than persons with PP: 51% vs 36% (p = 0.022) and 51% and 47% respectively thought their sitting posture could be improved (p = 0.670). 'Experienced lack of support in the wheelchair' was associated with most sitting-problems. Pain and instability were associated with dissatisfaction with sitting posture. CONCLUSION: Sitting-related problems and dissatisfaction with sitting posture were frequently reported by persons with long-standing SCI. Sitting problems appeared to associate with lacking support in the wheelchair/seating. A comprehensive feedback from the wheelchair user and a stability check (reach task), as part of the wheelchair/seating-user fitting, may contribute to prevention of sitting-related problems.

Correction: Experienced sitting-related problems and association with personal, lesion and wheelchair characteristics in persons with long-standing paraplegia and tetraplegia.

A correction to this paper has been published and can be accessed via a link at the top of the paper.

Midodrine for the weaning of vasopressor infusions.

WHAT IS KNOWN AND OBJECTIVE: Midodrine, an orally available α1-agonist indicated for the treatment of orthostatic hypotension, has been used at our institution as an adjunctive treatment to provide haemodynamic support to facilitate intravenous (IV) vasopressor weaning. Limited published data exist for this off-label use; thus, the objective of this study was to evaluate outcomes in patients who received midodrine for IV vasopressor weaning compared to control patients. METHODS: This retrospective comparison included adult ICU patients admitted to our institution from January 2007 to March 2012. The primary outcome was the time to IV vasopressor discontinuation after midodrine initiation. Secondary outcomes included a comparison between midodrine and control patients of the time from IV vasopressor discontinuation to ICU discharge, hospital and ICU length of stay (LOS), and the number of ICU readmissions. RESULTS AND DISCUSSION: The analysis included 188 patients (94 midodrine and 94 control). Patients discontinued IV vasopressors a median of 1·2 days (IQR 0·5-2·8) after midodrine initiation. ICU discharge occurred sooner after IV vasopressor discontinuation (0·8 vs. 1·5 days, P = 0·01), and 96% of patients remained off IV vasopressors after midodrine treatment. Hospital LOS was longer in midodrine patients (P < 0·01), but there were no differences in ICU LOS or readmissions. Adverse event rates after midodrine use were consistent with those observed in other studies. WHAT IS NEW AND CONCLUSION: Midodrine may serve as a useful adjunct to wean IV vasopressors in difficult-to-wean patients. Further studies are needed to assess the efficacy and safety of midodrine for this indication.

A More Nuanced Story: Pediatric Gender-Affirming Healthcare is Associated With Satisfaction and Confidence.

PURPOSE: Pediatric gender-affirming medical care has strong research evidence and support, and transition-related regret is uncommon. Misinformation about regret has nonetheless been used to limit adolescents from accessing this care. This study is the first of a 3-part initiative to clarify long-term satisfaction and regret related to pediatric gender-affirming care (GAC). METHODS: An anonymous survey was distributed to individuals of age 15 and older who participated in at least one prior appointment at a large pediatric gender clinic. The survey questions included (1) demographics; (2) use of gender-affirming interventions; (3) barriers to accessing medical interventions; (4) reasons for any discontinuation of medical interventions; (5) emotions associated with GAC; and (6) intervention-related regret. RESULTS: Participants (N = 150; Mage = 18.6) were predominantly transmasculine-identified and/or assigned female at birth (86%). The most common emotions associated with GAC were satisfaction (88.0%) and confidence (86.7%). A total of 141 participants reported taking hormones, 30 of whom reported ever discontinuing (21.3%). Among these, 11 have already resumed hormones, and 16 might resume. Of the three with no plan to resume hormones, one is fully satisfied with the results, and the remaining two no longer identify as transgender. Only one participant (0.7% of those who ever took hormones) wishes they had never started testosterone or had top surgery, both of which occurred in adulthood. DISCUSSION: Individuals who accessed GAC as adolescents are largely satisfied with this care. Care-related satisfaction and regret are more nuanced than sometimes portrayed and should not be used to limit access.

A new measure of sexual function in women with pelvic floor disorders (PFD): the Pelvic Organ Prolapse/Incontinence Sexual Questionnaire, IUGA-Revised (PISQ-IR).

INTRODUCTION AND HYPOTHESIS: The objective of this study was to create a valid, reliable, and responsive sexual function measure in women with pelvic floor disorders (PFDs) for both sexually active (SA) and inactive (NSA) women. METHODS: Expert review identified concept gaps and generated items evaluated with cognitive interviews. Women underwent Pelvic Organ Prolapse Quantification (POPQ) exams and completed the Incontinence Severity Index (ISI), a prolapse question from the Epidemiology of Prolapse and Incontinence Questionnaire (ISI scores), the Pelvic Floor Distress Inventory-20 (PFDI-20), and the Female Sexual Function Index (FSFI). Principle components and orthogonal varimax rotation and principle factor analysis with oblique rotation identified item grouping. Cronbach's alpha measured internal consistency. Factor correlations evaluated criterion validation. Change scores compared to change scores in other measures evaluated responsiveness among women who underwent surgery. RESULTS: A total of 589 women gave baseline data, 200 returned surveys after treatment, and 147 provided test-retest data. For SA women, 3 subscales each in 2 domains (21 items) and for NSA women 2 subscales in each of 2 domains (12 items) emerged with robust psychometric properties. Cronbach's alpha ranged from .63 to .91. For SA women, correlations were in the anticipated direction with PFDI-20, ISI, and FSFI scores, POPQ, and EPIQ question #35 (all p < .05). PFDI-20, ISI, and FSFI subscale change scores correlated with Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire International Urogynecological Association-revised (PISQ-IR) factor change scores and with mean change scores in women who underwent surgery (all p < .05). For NSA women, PISQ-IR scores correlated with PFDI-20, ISI scores, and with EPIQ question #35 (all p < .05). No items demonstrated differences between test and retest (all p ≥ .05), indicating stability over time. CONCLUSIONS: The PISQ-IR is a valid, reliable, and responsive measure of sexual function.

Development and evaluation of the clinimetric properties of the Medication-Related Osteonecrosis of the Jaw Quality of Life Questionnaire (MRONJ-QoL).

The purpose of this study was to develop a self-administered questionnaire (MRONJ-QoL) to assess the quality of life (QoL) of patients with medication-related osteonecrosis of the jaw (MRONJ). A prospective study was performed to develop and evaluate the questionnaire. The MRONJ-QoL was formulated through a review of the literature and interviews of experts and patients. Following development, it was administered to 60 patients with a diagnosis of MRONJ. The sensibility of the questionnaire was assessed by evaluating feasibility (via interviews of patients), face validity (via interviews of patients and experts), and content validity (via evaluation of internal consistency, floor/ceiling effects, and factor analysis). Reliability was evaluated by measuring intra-rater reliability. Construct validity of the questionnaire was evaluated by both cross-sectional and longitudinal comparisons, including comparing scores of the MRONJ-QoL to disease resolution at 6 months. The final MRONJ-QoL questionnaire consisted of 14 questions, demonstrating high internal consistency (Cronbach's alpha of 0.85) and good reliability (weighted kappa score of 0.65). At the 6-month follow-up, disease resolution was found to be significantly associated with improved MRONJ-QoL scores, suggesting validity of the questionnaire (P < 0.01). Therefore, this is a sensible, reliable, and valid questionnaire for evaluating the QoL of patients with MRONJ.

Treatment of HER2-positive metastatic breast cancer with lapatinib and capecitabine in the lapatinib expanded access programme, including efficacy in brain metastases--the UK experience.

BACKGROUND: The global lapatinib expanded access programme provided access to lapatinib combined with capecitabine for women with HER2-positive metastatic breast cancer (MBC) who previously received anthracycline, taxane and trastuzumab. METHODS: Progression-free survival (PFS) and safety data for 356 patients recruited from the United Kingdom are reported. Efficacy was assessed in 162 patients from the five lead centres, including objective tumour response rate (ORR), time to disease progression (TTP) and efficacy in those with central nervous system (CNS) metastases. Correlation of PFS and ORR with previous capecitabine treatment was also documented. RESULTS: Overall, PFS for the 356 UK patients was 21 weeks (95% CI: 17.6-24.7). In the 162 assessable patients, ORR was 21% (95% CI: 15-27%) and median TTP was 22 weeks (95% CI: 17-27). Efficacy was greater in capecitabine-naive patients (ORR 23 vs 16.3%, P=0.008). For 34 patients with CNS metastases, ORR was 21% (95% CI: 9-39%), with evidence of improvement in neurological symptoms, and median TTP was 22 weeks (95% CI: 15-28). CONCLUSIONS: Lapatinib combined with capecitabine is an active treatment option for women with refractory HER2-positive MBC, including those with progressive CNS disease.

Influence of granular activated carbon media properties on natural organic matter and disinfection by-product precursor removal from drinking water.

Operational and financial constraints challenge effective removal of natural organic matter (NOM), and specifically disinfection by-product (DBP) precursors, at remote and/or small sites. Granular activated carbon (GAC) is a widely used treatment option for such locations, due to its relatively low maintenance and process operational simplicity. However, its efficacy is highly dependent on the media capacity for the organic matter, which in turn depends on the media characteristics. The influence of GAC media properties on NOM/DBP precursor removal has been studied using a range of established and emerging media using both batch adsorption tests and rapid small-scale column tests. DBP formation propensity (DBPFP) was measured with reference to trihalomethanes (THMs) and haloacetic acids (HAAs). All GAC media showed no selectivity for specific removal of precursors of regulated DBPs; DBP formation was a simple function of residual dissolved organic carbon (DOC) levels. UV254 was found to be a good surrogate measurement of DBPFP for an untreated water source having a high DOC. Due to the much-reduced concentration of DBP precursors, the correlation was significantly poorer for the coagulation/flocculation-pretreateed water source. Breakthrough curves generated from the microcolumn trials revealed DOC removal and consequent DBP reduction to correlate reasonably well with the prevalence pores in the 5-10 nm range. A 3-6 fold increase in capacity was recorded for a 0.005-0.045 cm3/g change in 5-10 nm-sized pore volume density. No corresponding correlation was evident with other media pore size ranges.

Immunoglobulin kappa chain allotypes (KM) in onchocerciasis.

GM and KM allotypes, powerful tools for genetic characterization of human populations, have been shown to play an important role in genetic predisposition to some infectious diseases. Two diverse racial groups--Afro-Ecuadorians and Amerindians--living in a single restricted geographical area of Ecuador, appear to have different risk factors for acquisition and clinical expression of onchocerciasis, a disease caused by the filarial parasite Onchocerca volvulus. In this study, GM and KM allotypes were determined in 25 Afro-Ecuadorians and 24 Amerindians infected with Onchocerca volvulus (INF) and in putative immune individuals (PI). In Afro-Ecuadorians, the frequency of the homozygous KM 3 phenotype was significantly decreased in INF as compared with the PI group (20 vs. 68%; P= 0.0012), while the frequency of the heterozygous KM 1,3 phenotype was increased in INF as compared with the PI subjects (48 vs. 9%; P= 0.0044). These results suggest that in Afro-Ecuadorians KM 3 is associated with a lower relative risk (resistance), whereas KM 1,3 is associated with an increased risk (susceptibility) of onchocerciasis.

Social media as an open-learning resource in medical education: current perspectives.

PURPOSE: Numerous studies evaluate the use of social media as an open-learning resource in education, but there is a little published knowledge of empirical evidence that such open-learning resources produce educative outcomes, particularly with regard to student performance. This study undertook a systematic review of the published literature in medical education to determine the state of the evidence as to empirical studies that conduct an evaluation or research regarding social media and open-learning resources. METHODS: The authors searched MEDLINE, ERIC, Embase, PubMed, Scopus, and Google Scholar from 2012 to 2017. This search included using keywords related to social media, medical education, research, and evaluation, while restricting the search to peer reviewed, English language articles only. To meet inclusion criteria, manuscripts had to employ evaluative methods and undertake empirical research. RESULTS: Empirical work designed to evaluate the impact of social media as an open-learning resource in medical education is limited as only 13 studies met inclusion criteria. The majority of these studies used undergraduate medical education as the backdrop to investigate open-learning resources, such as Facebook, Twitter, and YouTube. YouTube appears to have little educational value due to the unsupervised nature of content added on a daily basis. Overall, extant reviews have demonstrated that we know a considerable amount about social media use, although to date, its impacts remain unclear. CONCLUSION: There is a paucity of outcome-based, empirical studies assessing the impact of social media in medical education. The few empirical studies identified tend to focus on evaluating the affective outcomes of social media and medical education as opposed to understanding any linkages between social media and performance outcomes. Given the potential for social media use in medical education, more empirical evaluative studies are required to determine educational value.

THM and HAA formation from NOM in raw and treated surface waters.

The disinfection by-product (DBP) formation potential (FP) of natural organic matter (NOM) in surface water sources has been studied with reference to the key water quality determinants (WQDs) of UV absorption (UV254), colour, and dissolved organic carbon (DOC) concentration. The data set used encompassed raw and treated water sampled over a 30-month period from 30 water treatment works (WTWs) across Scotland, all employing conventional clarification. Both trihalomethane (THM) and haloacetic acid (HAA) FPs were considered. In addition to the standard bulk WQDs, the DOC content was fractionated and analysed for the hydrophobic (HPO) and hydrophilic (HPI) fractions. Results were quantified in terms of the yield (dDBPFP/dWQD) and the linear regression coefficient R2 of the yield trend. The NOM in the raw waters was found to comprise 30-84% (average 66%) of the more reactive HPO material, with this proportion falling to 18-63% (average 50%) in the treated water. Results suggested UV254 to be as good an indicator of DBPFP as DOC or HPO for the raw waters, with R2 values ranging from 0.79 to 0.82 for THMs and from 0.71 to 0.73 for HAAs for these three determinants. For treated waters the corresponding values were significantly lower at 0.52-0.67 and 0.46-0.47 respectively, reflecting the lower HPO concentration and thus UV254 absorption and commensurately reduced precision due to the limit of detection of the analytical instrument. It is concluded that fractionation offers little benefit in attempting to discern or predict chlorinated carbonaceous DBP yield for the waters across the geographical region studied. UV254 offered an adequate estimate of DBPFP based on a mean yield of ∼2600 and ∼2800 µg per cm-1 absorbance for THMFP for the raw and treated waters respectively and ∼3800 and2900 µg cm-1 for HAAFP, albeit with reduced precision for the treated waters.

Comparison of the effect of sodium hyaluronate (Ophthalin) and hydroxypropylmethylcellulose (HPMC-Ophtal) on corneal endothelium, central corneal thickness, and intraocular pressure after phacoemulsification.

PURPOSE: To prospectively evaluate the effects of 2% hydroxypropyl-methylcellulose (HPMC-Ophtal) and sodium hyaluronate 1% (Ophthalin) on intraocular pressure, corneal thickness, and endothelial cell loss in small incision cataract surgery with implant. METHODS: A total of 110 patients undergoing routine phacoemulsification with implant received either 2% hydroxypropyl methylcellulose or sodium hyaluronate 1% as ophthalmic viscosurgical device. Pre- and postoperative slitlamp examination, intraocular pressure measurement (preoperatively and at 1-4 hours, 1 day, and 7 days postoperatively), ultrasonic pachymetry (preoperatively and at 1 week, 4-6 weeks, and 12 weeks post operatively), and corneal endothelial cell count (preoperatively and 12 weeks postoperatively) were performed. Data were analyzed using two-way analysis of variance. RESULTS: All measurements were comparable between the two groups preoperatively. Intraocular pressure was significantly lower in the Ophthalin group at 1 day post operatively, while no significant difference was found between the two groups on the 1-4 hours and 7 days examination. The central corneal thickness was not significantly different between the two groups at any postoperative visit . However, the mean cell density demonstrated a significant fall of 11.76% for Ophthalin and 4.27% for HPMC-Ophtal at 12 weeks post-operatively, the difference between the two being significant (p=0.009). CONCLUSIONS: 2% Hydroxypropyl methylcellulose, compared with sodium hyaluronate 1%, is superior in protecting the corneal endothelial cells, has the same effect on central corneal thickness, and is associated with slightly higher intraocular pressure 1 day post operatively. It compares favorably with sodium hyaluronate 1% and can be used as an effective and cheaper alternative in routine small incision cataract surgery with implant.

Use of maintenance endocrine therapy after chemotherapy in metastatic breast cancer.

BACKGROUND: For women with oestrogen receptor+ metastatic breast cancer (MBC), the options for systemic treatment include endocrine therapy (ET) and chemotherapy. For women whose disease is also HER2+, anti-HER2 therapies are also routinely used either with chemotherapy or less commonly with ET. Where chemotherapy is used as initial therapy, treatment is often discontinued due to cumulative toxicity in the absence of disease progression. In this setting, there is the option of introducing ET with the aim of prolonging response and delaying relapse. METHODS: Literature review revealed four trials addressing the question of whether there is a benefit from introducing ET following chemotherapy for MBC. We also sought evidence for alternative approaches, including concurrent chemotherapy and ET and continuing chemotherapy until disease progression. RESULTS: The evidence for the use of ET after chemotherapy in MBC is limited, and the trials done were small. Furthermore, they were performed at a time when both the chemotherapy regimens and ET were different from those used currently. Despite these limitations, there is probably a modest improvement in time to progression for the sequential use of ET after chemotherapy but with no overall survival benefit. An alternative approach, particularly considering agents with relatively low toxicity, such as orally bioavailable fluoropyrimidines, is to continue chemotherapy until disease progression. CONCLUSION: Where chemotherapy for MBC is discontinued due to toxicity, in the absence of progression, the use of ET, with its relatively low toxicity, is a reasonable approach with the aim of delaying relapse.

Pilot-scale spiral wound membrane assessment for THM precursor rejection from upland waters.

The outcomes of a pilot-scale study of the rejection of trihalomethanes (THMs) precursors by commercial ultrafiltration/nanofiltration (UF/NF) spiral-wound membrane elements are presented based on a single surface water source in Scotland. The study revealed the expected trend of increased flux and permeability with increasing pore size for the UF membranes; the NF membranes provided similar fluxes despite the lower nominal pore size. The dissolved organic carbon (DOC) passage decreased with decreasing molecular weight cut-off, with a less than one-third the passage recorded for the NF membranes than for the UF ones. The yield (weight % total THMs per DOC) varied between 2.5% and 8% across all membranes tested, in reasonable agreement with the literature, with the aromatic polyamide membrane providing both the lowest yield and lowest DOC passage. The proportion of the hydrophobic (HPO) fraction removed was found to increase with decreasing membrane selectivity (increasing pore size), and THM generation correlated closely (R2 = 0.98) with the permeate HPO fractional concentration.

Molecular cloning and characterization of a major allergen (Myr p I) from the venom of the Australian jumper ant, Myrmecia pilosula.

Five IgE-binding components were identified in the venom of the Australian jumper ant, Myrmecia pilosula using SDS polyacrylamide gel electrophoresis and Western blotting. A cDNA clone which encodes the entire amino acid sequence of one of the major IgE-binding venom allergens has been nucleotide sequenced. The IgE-binding determinants of this allergen are located in its C-terminal domain. Database searches, however, did not reveal any homology with any other known nucleotide or protein sequence. The sequenced allergenic polypeptide has, according to the convention recommended by the International Union of Immunological Societies (IUIS), been named Myr p I.

Identification of an IgE-binding determinant of the major allergen Myr p I from the venom of the Australian jumper ant Myrmecia pilosula.

The structure of the single allergenic determinant of the major ant venom allergen, Myr p I from the Australian jumper ant Myrmecia pilosula has been determined by inhibition studies with synthetic peptides. A 14 amino-acid C-terminal peptide sequence has been shown to constitute this determinant. Half-maximal inhibition of binding of ant venom-specific IgE antibodies to the native venom was obtained with this peptide at a concentration of 5 x 10(-8) M. This allergenic determinant was invariant for all ant venom-allergic subjects tested whose IgE antibodies recognized this allergen.

Coronary disease mortality and risk factors in black and white men. Results from the combined Charleston, SC, and Evans County, Georgia, heart studies.

BACKGROUND: Epidemiologic studies begun in the southeastern United States in the 1960s indicated that the prevalence of coronary disease was two to three times greater among white men than black men and also showed an excess incidence of coronary disease among white men, although hypertension was twice as prevalent among blacks. This study was conducted to determine if racial differences exist in coronary heart disease mortality and coronary risk factors. METHODS: Data from the two population-based cohorts of the Charleston, SC, and Evans County, Georgia, Heart Studies were pooled to make comparisons of coronary disease mortality and its risk factors. A total of 726 black men and 1346 white men aged 35 years or older in 1960 in the combined cohort were followed up for 30 years. RESULTS: There were 125 deaths among the black men and 323 deaths among the white men attributable to coronary disease; the age-adjusted rates were 5.0 per 1000 person-years in the black men and 6.5 per 1000 person-years in white men. Black-white coronary mortality risk ratios were 0.8 when age adjusted and 0.7 when also adjusted for other cardiovascular risk factors. Elevated systolic blood pressure and cigarette smoking were significant predictors of coronary mortality in black and white men. Serum total cholesterol level was a statistically significant risk factor only in white men. Higher education level was significantly protective in black and white men. CONCLUSIONS: Black men experienced significantly less coronary disease mortality than white men. Except for cholesterol level, the risk factors for coronary mortality in black and white men were similar.

Evaluation of anionic histological dyes as co-injectable cell markers in pre-implantation mouse embryos.

The enzyme horseradish peroxidase (HRP) is a widely used microinjectable cell marker for studying cell position, lineage, and migration in many kinds of animal embryos. Marked cells are easily identified because they darken when exposed to a chromophore and an HRP substrate such as hydrogen peroxide. This assay, however, requires cytochemical fixation. Thus, when HRP-marked cells need to be identified prior to fixation, visible co-injectants such as dyes and fluorescent substances have been used with HRP. Fluorescent substances have limitations because their excitation could be harmful to the marked cells. Visible but non-fluorescent co-injectants, however, would permit visualization of HRP-marked cells without inflicting such damage. We tested the compatibility of several histological dyes and electrolytic carriers with HRP iontophoresed as a cell marker in 2-cell mouse embryos. The dyes tested were Evans Blue, Cibacron Blue F3GA, Fast Green FCF, and Patent Blue Violet; the electrolytic carriers were KCl, K2SO4, CH3CO2K, and KH2PO4. The combination found most useful was Patent Blue Violet in K2SO4. Survival of embryos incubated to the blastocyst stage following injection with HRP + Patent Blue Violet in K2SO4 at the 2-cell stage was significantly greater than that of embryos injected with any other dye. Although the proportion of embryos undergoing the 8-cell-to-morula transition was somewhat decreased by this treatment, the proportion of embryos reaching the blastocyst stage was comparable to that in the uninjected (control) group. Our results indicate that Patent Blue Violet is a useful, HRP-co-injectable dye for short-term cell marking in preimplantation mouse embryos.