Dietary Intake and Quality among Stroke Survivors: NHANES 1999-2018

BACKGROUND

Nutrition is an important modifiable risk factor for prevention and treatment of stroke. However, examination of nutrient intake and diet quality in stroke survivors is limited.

OBJECTIVES

The aim of the study was to estimate usual nutrient intake and diet quality in US adults with and without a history of self-reported stroke.

METHODS

Using US National Health and Nutrition Examination Survey (NHANES) 1999-2018, we analyzed demographics, health history, and dietary intake data in 1626 individuals with a history of stroke matched for age, gender, and survey cycle to respective controls (n=1621) with no history of stroke. A minimum of one 24-h dietary recall was used to assess dietary intake. Diet quality was determined using Healthy Eating Index 2015 (HEI-2015) scores. Adult food security was assessed based on responses to the US Department of Agriculture Household Food Security Survey Module. Physical and mental limitations were assessed from responses to the NHANES Physical Functioning Questionnaire. Estimates were reported as mean (standard error).

RESULTS

In comparison to controls, stroke survivors were more likely to be food insecure, experience poverty, and report physical and mental limitations (P < .001, all comparisons). Stroke survivors were more likely to report excessive (% > acceptable macronutrient distribution range) intake for total fat (50.9 [2.7]% vs. 40.4 [2.2]%, P < .001) and inadequate intake (% < estimated average requirement) for calcium (54.6 [1.8]% vs. 43.5 [2.4]%, P = .001) and magnesium (66 [1.8] vs. 53.6 [1.8]%, P < .001). In addition, stroke survivors reported lower HEI-2015 total scores than controls (49.8 vs. 51.9, P < .001). Finally, HEI-2015 total scores were lower in stroke survivors who were food insecure and those with a lower income-to-poverty ratio (< 185%) (P = .001).

CONCLUSIONS

Dietary intake in stroke survivors was nutritionally poor, with suboptimal nutrient intake and lower overall diet quality compared with age- and gender-matched controls. Furthermore, poverty and food insecurity were more prevalent in stroke survivors and associated with worse diet quality.

Usual dietary fibre intake according to diabetes status in USA adults - NHANES 2013-2018

It is unknown if fibre intake differs across diabetes status in USA adults and is associated with glycaemic outcomes. This cross-sectional analysis utilised National Health and Nutrition Examination Survey cycles 2013-2018 data to estimate usual total dietary fibre intake in USA adults and across diabetes status (no diabetes, prediabetes and type II diabetes (T2D)). Associations among dietary fibre intake and glycaemic outcomes were also reported across groups. Adults (≥ 19 years) with at least one dietary recall were included. Diabetes status was determined from self-report data and measured HbA1c. Independent samples t tests were used to compare mean (se) intake across sub-populations. 14 640 adults (51·3 % female) with 26·4 % and 17·4 % classified as having prediabetes and T2D, respectively. Adults with T2D reported greater mean (se) dietary fibre intake compared with no T2D for females (9·5 (0·13) v. 8·7 (0·11) g/1000 kcal/d and males (8·5 (0·12) v. 7·7 (0·11) g/1000 kcal/d; P < 0·01)). However, only 4·2 (0·50)% and 8·1 (0·90)% of males and females with T2D, respectively, met the adequate intake for fibre. Fibre intake was associated with lower insulin (β = -0·80, P < 0·01), serum glucose (β = -1·35, P < 0·01) and Homeostatic Model Assessment for Insulin Resistance (β = -0·22, P < 0·01) in adults without diabetes, and no relationships in adults with prediabetes or T2D were found. Although dietary fibre intake was highest among adults with T2D, intake was suboptimal across all groups. In adults without diabetes, dietary fibre intake was associated with improved glycaemic outcomes and insulin resistance; however, these associations were attenuated by anthropometric and lifestyle covariates.

Resistant starch improves cardiometabolic disease outcomes: A narrative review of randomized trials

Healthy dietary patterns with adequate fiber improve cardiometabolic (CM) outcomes and attenuate disease progression. Resistant starch (RS) is a fermentable fiber that affects CM outcomes; however, studies are heterogeneous and inconsistent. Thus, the purpose of this narrative review is to assess the impact of RS intake by type and amount on CM outcomes while considering subject characteristics and trial duration. Randomized crossover or parallel studies (n = 31) were selected and compared according to acute (1 day; n = 12), medium (>1-30 days; n = 8), or long (>30 days; n = 11) duration. Most acute trials in healthy adults showed improvements in postprandial glycemic outcomes irrespective of RS type or amount. However, a more pronounced reduction occurred when test meals did not match for available carbohydrate. Daily RS intake had a minimal effect on CM outcomes in medium duration trials, but insulin resistant adults had better glycemic control at 4 weeks. Several longer duration trials (8-12 weeks) showed favorable CM outcomes with daily RS intake in adults with type 2 diabetes (T2D), but not in those at risk for T2D. Furthermore, some studies reported improved lipids, inflammatory biomarkers, and heart rate. Future studies should consider matching for available carbohydrates between the RS and control groups to understand the gut microbiome's role. Furthermore, energy and fiber should be considered. Overall, the acute intake of RS improves glycemic outcomes, and consuming RS at for least 4 and up to 8 to 12 weeks in adults with prediabetes and T2D, respectively, appears to improve CM outcomes.

Abstract 145: Dietary Intake And Quality Among Stroke Survivors Compared To Matched Controls Who Participated In The National Health And Nutrition Examination Survey: 1999 - 2018

Introduction: Nutrition is an important modifiable risk factor for the prevention and treatment of stroke. However, the examination of nutrient intake and diet quality in stroke survivors is limited. The purpose of this study was to estimate usual nutrient intake and diet quality in a nationally representative sample of US adults who have a history of stroke and compare to controls.

Methods: National Health and Nutrition Examination Survey 1999-2018 data were used to examine 1,626 stroke survivors matched for age, gender, and survey cycle to their respective controls (n=1,621), with no history of stroke. Data were collected on demographics and dietary intake and quality (assessed by Healthy Eating Index [HEI] 2015) from at least one reliable 24-h dietary recall. Estimates were reported as mean[SE]. Differences in continuous and categorical variables were assessed using independent-samples t-tests and Rao-Scott Chi-Squared tests, respectively.

Results: In comparison to controls, stroke survivors were more likely to report excessive (% > Acceptable Macronutrient Distribution Range) intake for total fat (50.9%[2.7] vs. 40.4%[2.2], p<.001), and inadequate intake (% < Estimated Average Requirement) for calcium (54.6%[1.8] vs. 43.5%[2.4], p=.001) and magnesium (66%[1.8] vs. 53.6%[1.8], p<.001). In addition, stroke survivors were less likely to report adequate intakes (% > Adequate Intake) for fiber (6.8%[0.9] vs. 11.9%[1.3]) and potassium (0.8%[0.3] vs. 1.0%[0.4]) (p<.001, all comparisons). Finally, stroke survivors reported lower HEI scores than controls (49.8 vs. 51.9, p<.001) which indicates lower diet quality, and were more likely to be food insecure, and report physical and mental limitations including difficulty preparing and eating meals compared to controls (p<.001, all comparisons).

Conclusions: Stroke survivors had lower overall diet quality and greater prevalence of inadequate nutrient intake profiles typically associated with increased risk of cardiovascular diseases including higher total fat intake and lower intake of key micronutrients and fiber compared to matched controls. Stroke survivors were also more likely to experience food insecurity and have physical and mental limitations that may directly impact dietary intake.

Influence of COVID-19 Pandemic Restrictions on College Students' Dietary Quality and Experience of the Food Environment

The COVID-19 pandemic restrictions sent college students online and off campus, potentially reducing access to healthy food. The objective of this cross-sectional, internet-based study was to use qualitative and quantitative survey methods to evaluate whether COVID-19 pandemic restrictions in Texas, USA affected college students’ ability to buy food, how/what they shopped for, how they prepared food, what they ate, how they felt about eating, and overall dietary quality (assessed using Healthy Eating Index [HEI] scores). Survey responses from 502 students (87.5% female; 59.6% nonwhite, mean age 27.5 ± 0.4 years, >50% graduate students) were analyzed. The qualitative analysis of open-ended questions revealed 110 codes, 17 subthemes, and six themes. Almost all students experienced changes in at least one area, the most common being changes in shopping habits. Participants with low or very low food security had lower HEI scores compared to food secure students (p = 0.047). Black students were more likely to report changes in their ability to buy food (p = 0.035). The COVID-19 restrictions varied in their impact on students’ ability to access sufficient healthy food, with some students severely affected. Thus, universities should establish procedures for responding to emergencies, including identifying at-risk students and mobilizing emergency funds and/or food assistance.

Usual Dietary Intake of Resistant Starch in US Adults from NHANES 2015-2016

BACKGROUND

Resistant starch (RS) confers many health benefits, mostly due to nonenzymatic human digestion and gut microbiota fermentation capacity. The usual intake of naturally occurring dietary RS in US adults is unclear.

OBJECTIVES

This study estimated usual daily RS intake in grams per 1000 kcal in US adults by sex, age, and ethnic group, as well as the most frequent food category contributing to RS intake using data from the NHANES 2015-2016.

METHODS

RS content of foods consumed was matched with Food and Nutrient Database for Dietary Studies food codes. The National Cancer Institute method was used to estimate adults' usual RS intake from 2 24-h dietary recalls. Day 1 RS contribution from food groups to overall RS intake was ranked for the total sample, across age-sex categories, and across ethnic groups.

RESULTS

In total, 5139 US adults (48.4% male) had a mean daily usual intake of RS of 1.9 ± 0.0 g/(1000 kcal⋅d). Males and females had a similar intake of RS [2.0 ± 0.0 g compared with 1.9 ± 0.0 g/(1000 kcal⋅d)] with no differences between sexes within the same age category. When comparing ethnic groups within each age category, the non-Hispanic white males and females had significantly lower RS intake than all other ethnic groups [range: 1.7-1.8 compared with 2.1-2.3 g RS/(1000 kcal⋅d), respectively], with no differences among the other ethnic groups. French fries and other fried white potatoes, rice, and beans, peas, and legumes were the most frequently consumed food categories contributing to RS intake in all adults.

CONCLUSIONS

US adults should improve the intake of natural RS food sources. Increasing RS intake will improve gastrointestinal health as a prebiotic and potentially increase insulin sensitivity with adequate consumption (e.g., ∼15 g/d).

Resistant Starch Content in Foods Commonly Consumed in the United States: A Narrative Review

Resistant starch (RS; types 1 to 5) cannot be digested in the small intestine and thus enters the colon intact, with some types capable of being fermented by gut microbes. As a fiber, types 1, 2, 3, and 5 are found naturally in foods, while types 2, 3, and 4 can be added to foods as a functional ingredient. This narrative review identifies RS content in whole foods commonly consumed in the United States. Scientific databases (n=3) were searched by two independent researchers. Ninety-four peer-reviewed articles published between 1982 and September 2018 were selected in which the RS was quantified and the food preparation method before analysis was suitable for consumption. The RS from each food item was adjusted for moisture if the RS value was provided as percent dry weight. Each food item was entered into a database according to food category, where the weighted mean±weighted standard deviation was calculated. The range of RS values and overall sample size for each food category were identified. Breads, breakfast cereals, snack foods, bananas and plantains, grains, pasta, rice, legumes, and potatoes contain RS. Foods that have been cooked then chilled have higher RS than cooked foods. Foods with higher amylose concentrations have higher RS than native varieties. The data from this database will serve as a resource for health practitioners to educate and support patients and clients interested in increasing their intake of RS-rich foods and for researchers to formulate dietary interventions with RS foods and examine associated health outcomes.

Accuracy of Water Delivery in Enteral Nutrition Pumps

BACKGROUND

Adequate delivery of both enteral formula and water in patients receiving enteral nutrition (EN) is critical. Pump accuracy has been identified as a factor impeding enteral formula delivery; however, rarely is enteral water delivery investigated. The purpose of this study was to explore accuracy of delivering 1 L of water by EN pumps using different flush volumes and hang heights.

METHODS

Three EN pumps were used in vitro to flush 1 L of water at 50 mL every hour for 20 hours (50 mL, 20 times per day) and 500 mL every 4 hours for 8 hours (500 mL, 2 times per day) at 0 in. and 18 in. (or 45.72 cm) hang heights. Fifteen runs were conducted at each volume and hang height per pump. Actual delivered enteral water, remaining volume in enteral feeding bags, and volume reported per pump were recorded.

RESULTS

Hang height of 18 in. delivered a mean 3.91% (95% CI, 3.25-4.57) more water than bags hung at 0 in. (P < .0005). When delivering water in 500 mL increments, 1.57% (95% CI, 0.92-2.23) more water was delivered than when delivered in 50 mL increments (P < .005).

CONCLUSION

Appropriate hang height recommendations improve enteral water delivery in patients receiving EN. The most accurate setting was 500 mL at 18 in., resulting in accurate water delivery in 97.8% of runs, whereas 50 mL at 0 in. delivered accurately 17.8% of the time. Appropriate bag hang height and water delivery volume is critical to maintain hydration status of patients receiving EN.

Chilled Potatoes Decrease Postprandial Glucose, Insulin, and Glucose-dependent Insulinotropic Peptide Compared to Boiled Potatoes in Females with Elevated Fasting Glucose and Insulin

Resistant starch (RS) has been shown to improve postprandial glycemia and insulin sensitivity in adults with metabolic syndrome. RS is found naturally in potatoes, where the amount varies based on cooking method and serving temperature. Thirty females with a mean BMI of 32.8 ± 3.7 kg/m2, fasting glucose of 110.5 mg/dL, and insulin of 10.3 µIU/L, completed this randomized, crossover study. A quantity of 250 g of boiled (low RS) and baked then chilled (high RS) russet potatoes were consumed on two separate occasions. Glycemic (glucose and insulin) and incretin response, subjective satiety, and dietary intake were measured. Results showed that the chilled potato elicited significant reductions at 15 and 30 min in glucose (4.8% and 9.2%), insulin (25.8% and 22.6%), and glucose-dependent insulinotropic peptide (GIP) (41.1% and 37.6%), respectively. The area under the curve for insulin and GIP were significantly lower after the chilled potato, but no differences were seen in glucose, glucagon-like peptide-1, and peptide YY, or overall subjective satiety. A higher carbohydrate and glycemic index but lower fat diet was consumed 48-hours following the chilled potato than the boiled potato. This study demonstrates that consuming chilled potatoes higher in RS can positively impact the glycemic response in females with elevated fasting glucose and insulin.

Influence of distribution of lean body mass on resting metabolic rate after weight loss and weight regain: comparison of responses in white and black women

BACKGROUND

Little is known about the effect of weight change on regional lean body mass (LBM) distribution or on racial differences in resting metabolic rate (RMR).

OBJECTIVE

The study compared total and regional LBM patterns in white and black women after weight loss and regain and assessed the influence of regional LBM on variances in RMR.

DESIGN

Eighteen white and 22 black women who did not differ in age, weight, and height were studied 3 times: in the overweight state, after weight reduction to the normal-weight state, and after 1 y without intervention. Total and regional lean and fat masses were assessed by dual-energy X-ray absorptiometry.

RESULTS

White and black women did not differ significantly in mean (+/- SD) weight loss (13.4 +/- 3.6 and 12.7 +/- 3.2 kg, respectively) and regain (6.1 +/- 5.5 and 6.4 +/- 5.4 kg, respectively). Black subjects had significantly less trunk LBM and significantly more limb LBM at each time point (P < 0.05). In both races, weight regain was associated with significant increases in limb LBM (P < 0.05) but not in trunk LBM (P = 0.21). RMR, adjusted for total LBM and fat mass, was significantly higher in white women after weight loss (P < 0.01) and regain (P < 0.01). However, no racial difference was found when RMR was adjusted for LBM distribution.

CONCLUSIONS

In both races, trunk LBM decreased with weight loss and remained lower, despite significant weight regain, which potentially reflected decreased organ mass. Regional LBM distribution explained the racial difference in RMR.

Lessons learned in adopting endovascular techniques for treating abdominal aortic aneurysm

HYPOTHESIS

Endovascular exclusion of abdominal aortic and common iliac aneurysms can be performed safely, and in the short term represents a feasible alternative to traditional, open aneurysm repair.

PATIENTS AND METHODS

Forty-one patients were treated with endovascular grafts for 39 abdominal aortic and 2 common iliac artery aneurysms.

RESULTS

All devices were successfully deployed. The size of the abdominal aortic aneurysms varied from 4.9 to 11.9 cm (average, 6.13 cm). The median procedure time was 195 minutes. There was one iliac artery rupture, which required celiotomy for repair. The hospital stay varied from 2 to 39 days (average, 6.7 days). The perioperative mortality rate was 2.4%. Sixteen patients (39%) had groin wound complications. Ten patients (24%) had evidence of contrast (endoleak) within the aneurysm sac on completion of the procedure. There were no obvious direct leaks from either the point of proximal or distal fixation. Seven of these endoleaks have resolved spontaneously. Two patients required additional procedures in the postoperative period to treat endoleak. The final patient has evidence of persistent endoleak on 3-month surveillance computed tomography scan. Major late problems occurred in 3 patients.

CONCLUSION

Patients with large abdominal aortic aneurysms and considerable cardiac comorbidity can safely undergo endovascular aneurysm repair. Femoral groin wound complications resulting in prolonged hospitalization remain the major cause of perioperative morbidity. In contradistinction to open aneurysm repair, long-term surveillance is essential to detect migration of the device and identify flow within the residual aneurysm sac-complications that could lead to aneurysm rupture following endovascular repair.

Shear force regulates matrix metalloproteinase activity in human saphenous vein organ culture

BACKGROUND

Development of vein graft intimal hyperplasia has been related both to shear force and to the activity of matrix metalloproteinases (MMPs). Little data are available regarding the effects of shear on MMP expression and activity. The aim of this study was to examine the relationship among shear force, metalloproteinase activity, and intimal thickening in human saphenous vein segments maintained in organ culture.

MATERIALS AND METHODS

Segments of human saphenous vein were cultured under static conditions, or perfused under low-flow and high-flow conditions in a perfusion apparatus for 7 days. Metalloproteinase levels and activities were measured using ELISA and substrate gel zymography, respectively. Intimal thickening was determined by morphometric analysis. Results were compared with control vein tissue, which was not subjected to organ culture, using a one-way ANOVA.

RESULTS

A 13% increase in proteolytic activity was noted on substrate gel zymography at 68-72 kDa in high-flow vein tissue. The protein content of MMP-2, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and TIMP-2 was increased in high-flow vein tissue by 21%, 126%, more than 100-fold, and 86%, respectively. In culture media bathing the outside of the vein, TIMP-2 was increased in high-flow specimens, while TIMP-1 was inversely related to flow rate. Intimal thickening was directly related to flow rates, and was progressively increased in the low-flow and high-flow groups by 3-fold and 4-fold, respectively.

CONCLUSIONS

Metalloproteinase levels in human saphenous vein cultures are related to shear force. MMP levels and activity correlate with the degree of intimal thickening. This model may provide a valuable tool for the analysis of physical forces and their influence on intimal thickening in human saphenous vein.

Transforming practice organizations to foster lifelong learning and commitment to medical professionalism

Practice organizations will increasingly engage in activities that are the functional equivalents of continuing medical education. The authors maintain that if these activities are properly structured within practice organizations, they can become powerful engines of socialization to enhance physicians' lifelong learning and commitment to medical professionalism. They propose that this promise can be realized if new or reformed practice organizations combine education and service delivery and institutionalize processes of individual and collective reflection. The resulting "institutions of reflective practice" would be ones of collegial, experiential, reflective lifelong learning concerning the technical and normative aspects of medical work. They would extend recent methods of medical education such as problem-based learning into the practice setting and draw on extant methods used in complex organizations to maximize the advantages and minimize the disadvantages that practice organizations typically present for adult learning. As such, these institutions would balance the potentially conflicting organizational needs for, on the one hand, (1) self-direction, risk taking, and creativity; (2) specialization; and (3) collegiality; and, on the other hand, (4) organizational structure, (5) coordination of division of labor, and (6) hierarchy. Overall, this institutionalization of reflective practice would enrich practice with education and education with practice, and accomplish the ideals of what the authors call "responsive medical professionalism." The medical profession would both contribute and be responsive to social values, and medical work would be valued intrinsically and as central to practitioners' self-identity and as a contribution to the public good.

Combined blunt cardiac and pericardial rupture: review of the literature and report of a new diagnostic algorithm

The spectrum of blunt cardiac injury varies from the asymptomatic cardiac concussion to the immediately fatal cardiac rupture. Although the majority of victims sustaining blunt cardiac rupture die before receiving medical attention, some survive to evaluation. The diagnosis of cardiac rupture, if established, typically results from the signs and symptoms of pericardial tamponade. However, some patients may have remarkably few signs and symptoms suggestive of cardiac injury and represent a significant diagnostic challenge. We provide two cases of cardiac rupture in which the diagnosis was delayed by the presence of an associated pericardial tear with decompression into the mediastinum and pleural space. In neither of the cases did existing institutional algorithms for blunt cardiac injury assist in establishing the diagnosis before the acute demise of the patient. The presence of a coexisting pericardial injury in these patients with blunt cardiac rupture obscured the diagnosis, leading to the deaths of these patients. A discussion of these two cases and review of the literature is provided with recommendations for diagnostic algorithms in patients sustaining blunt thoracic trauma with possible cardiac and pericardial injury.

Dengue surveillance in Texas, 1995

Dengue epidemics have been occurring in the Caribbean and Central and South America, including Mexico. In 1995, the proximity of these epidemics increased the possibility of cases occurring in Texas. In response, medical and community educational materials were distributed and active surveillance for dengue cases was initiated. By the end of the year, sera from more than 360 patients were tested for anti-dengue antibody. Twenty-nine cases were detected statewide; seven cases in southern Texas were locally acquired.

A comparison of segmental and wrist-to-ankle methodologies of bioimpedance analysis

The common approach of bioelectrical impedance analysis to estimate body water uses a wrist-to-ankle methodology which, although not indicated by theory, has the advantage of ease of application particularly for clinical studies involving patients with debilitating diseases. A number of authors have suggested the use of a segmental protocol in which the impedances of the trunk and limbs are measured separately to provide a methodology more in keeping with basic theory. The segmental protocol has not, however, been generally adopted, partly because of the increased complexity involved in its application, and partly because studies comparing the two methodologies have not clearly demonstrated a significant improvement from the segmental methodology. We have conducted a small pilot study involving ten subjects to investigate the efficacy of the two methodologies in a group of normal subjects. The study did not require the independent measure of body water, by for example isotope dilution, as the subjects were maintained in a state of constant hydration with only the distribution between limbs and trunk changing as a result of change in posture. The results demonstrate a significant difference between the two methodologies in predicting the expected constancy of body water in this study, with the segmental methodology indicating a mean percentage change in extracellular water of -2.2%, which was not significantly different from the expected null result, whereas the wrist-to-ankle methodology indicated a mean percentage change in extracellular water of -6.6%. This is significantly different from the null result, and from the value obtained from the segmental methodology (p = 0.006). Similar results were obtained using estimates of total body water from the two methodologies.

Electrostimulation: addiction treatment for the coming millennium

At a period of fundamental review of the health care system, it is timely to re-assess one of medicine's most intractable problems--the treatment of addictions. The apparently insoluble dilemmas posed by the acute and chronic withdrawal syndromes underlie universally high drop-out and relapse rates. In a decade of HIV and AIDS infection, poly-substance addiction, potent street drugs, and ossified treatment strategies, it is urgent that policy formulators investigate seriously a flexible system of non-pharmacological transcranial electrostimulation treatment, based on its record of rapid, safe, and cost-effective detoxification in several countries, as one innovative contribution to the challenges presented by addiction in the 1990s. This is a brief report of the introduction of NeuroElectric Therapy (NET) into Germany, describing the responses of the first 22 cases. The daily progress of a heroin addict and a methadone addict are detailed: both were treated as outpatients for 8 hours daily, for 7 and 10 days respectively.

A monoclonal antibody to human macrophage gangliosides inhibits macrophage migration

Gangliosides have diverse immunoregulatory properties. The gangliosides endogenous to macrophages may have immunoregulatory properties that distinguish them from other gangliosides. Gangliosides have been indirectly implicated in macrophage migration as putative cell surface receptors for migration inhibitory factor (MIF). In this study, a monoclonal antibody to human macrophage gangliosides (antibody 25F4) was developed and characterized. This is the first report of the development of monoclonal antibodies to gangliosides of macrophages of any species. Thin-layer chromatographic immunostaining indicated that antibody 25F4 recognized major gangliosides of human macrophages but did not recognized those previously identified as containing fucose. Immunofluorescent surface labeling of viable human macrophages indicated that antibody 25F4 recognized a surface-accessible epitope, present on all cells, and that this was abolished with lipid depletion of macrophage membranes. This epitope was not present on several human nonmacrophage cells. Finally, human macrophages pretreated with antibody 25F4 demonstrated striking inhibition of migration of an agarose droplet assay, whereas an irrelevant monoclonal antibody or monoclonal antibodies to nonganglioside surface epitopes of human macrophages had no effect on migration. Migration inhibition occurred even though antibody 25F4 was removed from the extracellular milieu and was not due to formation of cellular aggregates. These studies support a role for human macrophage gangliosides in macrophage migration.

Outcomes of residential treatment of substance abuse in hospital- and community-based programs

OBJECTIVE

The study sought to determine whether inpatient readmission rates differed for patients with substance use disorders who were treated in either hospital-based or community-based transitional residential care. Length of residential care and intensity of outpatient mental health aftercare were examined as predictors of readmission.

METHODS

Department of Veterans Affairs nationwide databases were used to document readmissions at one- and two-year intervals for male inpatients treated for substance use disorders who were discharged either to hospital-based (N = 2,190) or community-based (N = 4,490) residential care. Patients with and without concomitant psychiatric diagnoses were identified.

RESULTS

Patients treated in community-based residential programs had lower one- and two-year readmission rates than patients who received hospital-based residential care. Longer episodes of residential care and more outpatient mental health care were also associated with lower readmission rates. Among patients with concomitant psychiatric disorders, those in hospital-based care benefited more from longer episodes of residential care and more intensive outpatient mental health aftercare. Residential care, longer episodes of care, and more outpatient mental health care were independent predictors of lower one- and two-year readmission rates after patient-based risk factors were controlled.

CONCLUSIONS

The findings highlight the value of providing adequate amounts of residential and outpatient care for patients in substance abuse treatment, especially patients with concomitant psychiatric disorders.

n-Butyrate mediation of ganglioside expression of human and murine cancer cells demonstrates relative cell specificity

1. n-Butyrate, a short chain fatty acid produced by colonic fermentation, induces differentiation in human neoplastic cell lines, and reduces expression in vitro of a sialyltransferase that glycosylates N-linked glycoproteins in hepatoblastoma cells. Gangliosides are amphipathic, sialylated glycosphingolipids that undergo profound changes in many transformed cells and may protect neoplastic cells from host immune surveillance. Colonic mucosal cells are exposed to luminal short-chain fatty acid concentrations of up to 80 mmol/l, and there is some evidence that short-chain fatty acids may alter ganglioside expression in colon cancer cells. 2. Because of the importance of gangliosides in cancer pathogenesis, we investigated the effects of n-butyrate on ganglioside expression of colonic (human and murine) and non-colonic cancer cells. 3. Three separate colon cancer cell lines (LS174T, T84 and MCA-38), when butyrate treated, demonstrated striking amplification of specific individual gangliosides. However, the total lipid-bound sialic acid content of gangliosides of butyrate-treated LS174T cells diminished. In contrast to earlier reports, n-butyrate did not mediate expression of all gangliosides and specifically did not mediate expression of GM3. This effect persisted even after removal of butyrate. 4. In contrast, exposure of extracolonic cells to butyrate, including cervical cancer (HeLa) and laryngeal cancer (HEp-2) cell lines in this study and hepatoblastoma cells (Hep G2) in our previous work, caused no detectable changes in ganglioside expression. 5. In conclusion, our results indicate a relative tissue specificity of butyrate-mediated alterations in ganglioside expression that is not universal but is limited to specific gangliosides.

Identification of enteroviruses by indirect immunofluorescence using monoclonal antibodies

BACKGROUND

Serum neutralization (Nt) is used most often to type enterovirus isolates, but it is labor-intensive, expensive, and supplies of reference antisera for Nt are limited. Alternative methods of enterovirus typing are needed.

OBJECTIVES

To investigate the use of indirect immunofluorescence (IFA) with commercially available monoclonal antibodies (MAbs) as an alternative to Nt for the identification of enteroviruses.

STUDY DESIGN

Two MAb blends (one for coxsackie B viruses and one for echoviruses 4, 6, 9, 11, 30, and 34) and a coxsackie A9 MAb were used to screen 465 clinical isolates over a period of two years. Virus isolates which tested positive with one of the blends were typed with the individual MAbs of the respective blend. Individual MAbs for polioviruses 1, 2, and 3 acquired late in the study were used to screen 45 viral isolates.

RESULTS

The antibodies identified 251/465 (54%) of the total number of isolates tested. IFA results for 451 of 465 viral isolates were in agreement with conventional identification methods. The sensitivity of the IFA screen using the MAb blends and coxsackie A9 MAb was 93% and the specificity was 99%. Thirteen discrepant isolates were negative by IFA, with twelve positive by Nt for echovirus 30 and one isolate positive by Nt for coxsackie A9. The remaining discrepant isolate was positive by IFA for both coxsackie A9 and coxsackie B5, but positive by Nt for coxsackie A9 only.

CONCLUSIONS

IFA is highly specific for the identification of enteroviruses, but may not be sensitive enough to identify all strains within an enterovirus type. Procedures which utilize an IFA screen and confirm final results by Nt decrease turnaround time and reduce the number of cell culture tubes required for the identification of each enterovirus isolate.

Services for maintaining independence

Providing a range of health-related services may be necessary for some elderly to remain in independent living environments. Wellness Centers can identify those at risk for disease, promote self-care techniques, and assess the need for other health services. Entrepreneural nurses have the opportunity to seek out congregate housing sites with large aging populations to create ways of promoting healthy lifestyles and a higher quality of life for older persons. A holistic approach to health care helps the elderly to manage chronic disease, maintain high levels of functioning, and promote self-responsibility.

Hydrogen peroxide-mediated inhibition of T-cell response to mitogens is a result of direct action on T cells

Hydrogen peroxide, a reactive oxygen intermediate produced by activated neutrophils, has been shown to inhibit the response of human T lymphocytes to mitogens and alloantigens. Since hydrogen peroxide is known to react with iron and to induce lipid peroxidation, we compared the effects of hydrogen peroxide and a lipid peroxidation product, malondialdehyde, on the response of human peripheral blood mononuclear cells to T-cell mitogens. Peripheral blood mononuclear cells pretreated with 1 mmol/L of malondialdehyde, washed, and resuspended in fresh medium exhibited no inhibition of phytohemagglutinin responsiveness. Peripheral blood mononuclear cells treated in the same manner but with 200 mumol/L of hydrogen peroxide were inhibited by more than 95%. The addition of ferric edetate did not alter the inhibitory effects of 50 to 100 mumol/L of hydrogen peroxide, nor did the addition of deferoxamine, an iron chelator. These studies suggest that exogenous lipid peroxidation does not affect lymphocyte activation but that hydrogen peroxide has a direct inhibitory effect. Although monocytes are necessary for T-cell mitogenic responses, the effect of hydrogen peroxide was found to be directed at T lymphocytes. Exposure of T cells to a single dose of 200 mumol/L of hydrogen peroxide resulted in more than 71% suppression of the proliferative response measured 48 hours later, but the effect was spontaneously reversed by 72 to 96 hours. Repeated exposure of the cells to hydrogen peroxide resulted in continued inhibition of the proliferative response. These findings suggest that hydrogen peroxide produced by inflammatory phagocytic cells might be capable of suppressing the immune response of nearby T lymphocytes.

Free radical metabolism of hydralazine. Binding and degradation of nucleic acids

The binding of hydralazine, a hydrazine-containing hypotensive drug, to nucleic acids has been studied. Binding of this drug to biopolymers was assayed using spin-trapping techniques in the presence of various metal ions, which produce free radical intermediates from hydralazine [B. K. Sinha and A. G. Motten, Biochem, biophys. Res. Commun. 105, 1044 (1982)]. Some interaction was detected with the single-stranded nucleic acids. Hydralazine binds strongly to the native DNA, most likely by intercalation of the drug into DNA bases. In the presence of nucleic acids and metal ions, hydralazine stimulated the production of OH(.) radicals which was inversely proportional to the degree of binding. Aldehyde formation in DNA was also induced by hydralazine which was stimulated by superoxide dismutase and inhibited by catalase.

Periplasmic enzymes in Bdellovibrio bacteriovorus and Bdellovibrio stolpii

When cells of either Bdellovibrio bacteriovorus 109J or Bdellovibrio stolpii UKi2 were subjected to osmotic shock by treatment with sucrose-EDTA and MgCl2 solutions, only trace amounts of proteins or enzyme activities were released into the shock fluid. In contrast, when nongrowing cells were converted to motile, osmotically stable, peptidoglycan-free spheroplasts by penicillin treatment, numerous proteins were released into the suspending fluid. For both species, this suspending fluid contained substantial levels of 5'-nucleotidase, purine phosphorylase, and deoxyribose-phosphate aldolase. Penicillin treatment also released aminoendopeptidase N from B. bacteriovorus, but not from B. stolpii. Penicillin treatment did not cause release of cytoplasmic enzymes such as malate dehydrogenase. The data indicated that bdellovibrios possess periplasmic enzymes or peripheral enzymes associated with the cell wall complex. During intraperiplasmic bdellovibrio growth, periplasmic and cytoplasmic enzymes of the Escherichia coli substrate cell were not released upon formation of the spherical bdelloplast during bdellovibrio penetration. Most of the E. coli enzymes were retained within the bdelloplast until later in the growth cycle, when they became inactivated or released into the suspending buffer or both.

The influence of electrostimulation on hexobarbital induced loss of righting reflex in rats

Electrostimulation (ES) of slow (SF, 10 Hz) or fast (FF, 500 Hz) frequency decreases the sleeping time of rats anaesthetized by administration of acute doses of hexobarbital. When ES is applied via the ears, both SF and FF are equally efficient in reducing the loss of righting reflex (LRR), whereas if ES is applied peripherally via the paws, only FF decreases the acute narcosis time. Applied cranially, either continuous stimulation or administration of intermittent current (5 minutes on and off) were equally effective in reducing narcosis. A decreased period of 30 minutes' continuous stimulation will reduce sleeping time only if administered immediately after LRR. When restrained animals received ES for periods of up to 3 hours prior to administration of the barbiturate, the sleeping time of the stimulated and sham treated animals were not significantly different.