Performance of ceftazidime/avibactam susceptibility testing methods against clinically relevant Gram-negative organisms

OBJECTIVES

To ensure the accuracy of susceptibility testing methods for ceftazidime/avibactam.

METHODS

The performances of the Etest (bioMérieux), 30/20 μg disc (Hardy diagnostics) and 10/4 μg disc (Mast Group) were evaluated against the reference broth microdilution (BMD) method for 102 clinically relevant Gram-negative organisms: 69 ceftazidime- and meropenem-resistant Klebsiella pneumoniae and 33 MDR non-K. pneumoniae. Essential and categorical agreement along with major and very major error rates were determined according to CLSI guidelines.

RESULTS

A total of 78% of isolates were susceptible to ceftazidime/avibactam. None of the three methods met the defined equivalency threshold against all 102 organisms. The Etest performed the best, with categorical agreement of 95% and major errors of 6.3%. Against the 69 ceftazidime- and meropenem-resistant K. pneumoniae, only the Etest and the 10/4 μg disc met the equivalency threshold. None of the three methods met equivalency for the 33 MDR isolates. There were no very major errors observed in any analysis. These results were pooled with those from a previous study of 74 carbapenem-resistant Enterobacteriaceae and data from the ceftazidime/avibactam new drug application to define optimal 30/20 μg disc thresholds using the error-rate bound model-based approaches of the diffusion breakpoint estimation testing software. This analysis identified a susceptibility threshold of ≤19 mm as optimal.

CONCLUSIONS

Our data indicate that the Etest is a suitable alternative to BMD for testing ceftazidime/avibactam against ceftazidime- and meropenem-resistant K. pneumoniae. The 30/20 μg discs overestimate resistance and may lead to the use of treatment regimens that are more toxic and less effective.

Cognitive function in a middle aged cohort is related to higher quality dietary pattern 5 and 25 years earlier: the CARDIA study

BACKGROUND

Preserving cognitive function is an important public health issue. We investigated whether dietary pattern associates with cognitive function in middle-age.

METHODS

We studied 2435 participants in the community-based Coronary Artery Risk Development in Young Adults (CARDIA) study of black and white men and women aged 18-30 in 1985-86 (year 0, Y0). We hypothesized that a higher A Priori Diet Quality Score, measured at Y0 and Y20, is associated with better cognitive function measured at Y25. The diet score incorporated 46 food groups (each in servings/day) as the sum of quintile ranks of food groups rated beneficial, 0 for food groups rated neutral, and reversed quintile ranks for food groups rated adverse; higher score indicated better diet quality. Y25 cognitive testing included verbal memory (Rey Auditory-Verbal Learning Test (RAVLT)), psychomotor speed (Digit Symbol Substitution Test (DSST)) and executive function (Stroop).

RESULTS

Per 10-unit higher diet score at Y20, the RAVLT was 0.32 words recalled higher, the DSST was 1.76 digits higher, and the Stroop was 1.00 seconds+errors lower (better performance) after adjusting for race, sex, age, clinic, and energy intake. Further adjustment for physical activity, smoking, education, and body mass index attenuated the association slightly. Diet score at Y0 and increase in diet score over 20 years were also positively associated with each cognitive test.

CONCLUSIONS

A higher quality dietary pattern was associated with better cognitive function 5 years and even 25 years later in apparently healthy middle-aged adults.

Diet quality and markers of endothelial function: the CARDIA study

BACKGROUND AND AIM

Dietary patterns are associated cross-sectionally with cellular adhesion molecules (CAMs). We studied prospective associations of three dietary patterns with CAMs.

METHODS AND RESULTS

In the Coronary Artery Risk Development in Young Adults (CARDIA) study, diet was assessed at years 0 (1985-86) and 7 (1992-93) examinations. Four circulating CAMs (E-selectin, P-selectin, soluble intercellular adhesion molecule 1 (sICAM-1), and vascular cellular adhesion molecule (VCAM)) were assayed at years 7 and 15 (2000-01). We created one index score "A Priori Diet Quality Score" and derived dietary patterns using principal components analysis (PCA). Multivariable linear regression models predicted year 15 CAMs from averaged (year 0/7) dietary patterns. The A Priori Diet Quality Score rated 46 food groups beneficial, neutral or adverse based on hypothesized health effects. We derived two PCA dietary patterns: "fruit and vegetables (FV)" (high intakes of fruit, vegetables, and whole grains) and "meat" (high intakes of red meat, refined grain, and butter). All dietary patterns were related to E-selectin and sICAM-1. P-selectin was not related to the FV dietary pattern. VCAM was only related to the A Priori Diet Quality Score. Strongest associations were for the meat dietary pattern with E-selectin (effect size 28% of an SD (+3.9/13.7 ng/mL)) and P-selectin (effect size 37% of an SD (+4.1/11.2 ng/mL)) and the A Priori Diet Quality Score with sICAM-1 (effect size 34% of an SD (-15.1/44.7 ng/mL)) and VCAM (effect size of 26% of an SD (-45.1/170.3 ng/mL)).

CONCLUSION

This prospective analysis suggests that dietary patterns are associated with CAMs.

Detection limits for time-resolved coherent two-dimensional vibrational spectroscopy

Coherent two-dimensional vibrational spectroscopy is performed using doubly vibrationally enhanced four-wave mixing in dilute solutions of carbon disulfide using an ultrafast (< or = 1 ps) laser pulse system. The nonresonant electronic background and singly resonant coherent anti-Stokes Raman scattering contributions are suppressed by delaying the excitation pulses. With this suppression, we measured detection limits of 8 x 10(-5) M CS2 in bromochloromethane.

Dietary fat and incidence of type 2 diabetes in older Iowa women

OBJECTIVE

To examine the associations between reported intakes of dietary fat and incident type 2 diabetes.

RESEARCH DESIGN AND METHODS

We studied the relation between dietary fatty acids and diabetes in a prospective cohort study of 35,988 older women who initially did not have diabetes. Diet was assessed with a food frequency questionnaire at baseline, and 1,890 incident cases of diabetes occurred during 11 years of follow-up.

RESULTS

After adjusting for age, smoking, alcohol consumption, BMI, waist-to-hip ratio, physical activity, demographic factors, and dietary magnesium and cereal fiber, diabetes incidence was negatively associated with dietary polyunsaturated fatty acids, vegetable fat, and trans fatty acids and positively associated with omega-3 fatty acids, cholesterol, and the Keys score. After simultaneous adjustment for other dietary fat, only vegetable fat remained clearly related to diabetes risk. Relative risks across quintiles of vegetable fat intake were 1.00, 0.90, 0.87, 0.84, and 0.82 (P = 0.02). Diabetes risk was also inversely related to substituting polyunsaturated fatty acids for saturated fatty acids and positively correlated to the Keys dietary score.

CONCLUSIONS

These data support an inverse relation between incident type 2 diabetes and vegetable fat and substituting polyunsaturated fatty acids for saturated fatty acids and cholesterol.

Perifoveal vitreous detachment is the primary pathogenic event in idiopathic macular hole formation

OBJECTIVE

To evaluate the relationship between the posterior vitreous cortex and the posterior retina in eyes with early stages of idiopathic macular hole formation.

METHODS

Twenty-six eyes of 26 consecutive patients with stage 1 or stage 2 idiopathic macular hole underwent complete ophthalmologic examination, contact lens biomicroscopy, and B-scan ultrasonography or vitreoretinal surgery or both. In eyes that were operated on, the posterior cortical vitreous layer was meticulously examined with a silicone-tipped cannula prior to inducing a posterior vitreous detachment.

RESULTS

In 25 (96%) of 26 eyes, one or more examination techniques revealed a shallow, localized detachment of the perifoveal vitreous, typically extending to the level of the vascular arcades. Among these 25 eyes, the posterior hyaloid membrane separation was detectable biomicroscopically in 4 (16%) of 25 eyes, ultrasonographically in 17 (74%) of 23 eyes, and intraoperatively in 23 (100%) of 23 eyes. Persistent vitreous adherence to the foveola was evident in 6 (100%) of 6 eyes with a stage 1 hole and in 12 (92%) of 13 eyes with a stage 2 hole but no operculum.

CONCLUSIONS

These findings suggest that localized perifoveal vitreous detachment (an early stage of age-related posterior vitreous detachment) is the primary pathogenic event in idiopathic macular hole formation. We postulate that detachment of the posterior hyaloid from the pericentral retina leads to foveal dehiscence by exerting anterior traction on the foveola and by localizing into the foveola the dynamic vitreous traction associated with ocular rotations.

Fiber from whole grains, but not refined grains, is inversely associated with all-cause mortality in older women: the Iowa women's health study

BACKGROUND

Inconsistencies in epidemiologic findings relating grain fiber to chronic disease may be explained by differentiating nutrient-rich fiber derived from whole grain vs. nutrient-poor fiber derived from refined grain.

OBJECTIVE

Given that phytochemicals are most varied and abundant in the outer layers of grains, we tested the hypothesis that whole grain fiber consumption is associated with a reduced mortality risk in comparison to a similar amount of refined grain fiber.

DESIGN

11,040 postmenopausal women enrolled in the Iowa Women's Health Study, matched on total grain fiber intake, but differing in the proportion of fiber consumed from whole vs. refined grain, were followed from baseline in 1986 through 31 December, 1997, during which time 1,341 deaths occurred in 124,823 observed woman-years.

RESULTS

After multivariate adjustment in proportional hazards regression, women who consumed on average 1.9 g refined grain fiber/2,000 kcal and 4.7 g whole grain fiber/2,000 kcal had a 17% lower mortality rate (RR=0.83, 95% CI=0.73-0.94) than women who consumed predominantly refined grain fiber: 4.5 g/2,000 kcal, but only 1.3 g whole grain fiber/2,000 kcal.

CONCLUSION

Inferences from studies that have reported associations between grain fiber intake and morbidity or mortality may be limited by not differentiating fiber sources. Future studies should distinguish fiber from whole vs. refined grains. Public health policy should differentiate whole grains from refined, and recommend increased consumption of the former.

Effects of sleep deprivation on free-operant avoidance

Two studies examined effects of sleep deprivation on free-operant avoidance by rats. In Experiment 1, a 5-s shock-shock (SS) interval and 20-s response-shock (RS) interval produced baseline performances, which were reestablished after each experimental manipulation. Once baselines were established, animals were exposed to 24, 48, or 96 hr of sleep deprivation and equivalent periods of home cage and food restriction as a control condition. Compared to baseline, sleep deprivation increased response rates by increasing the proportion of brief interresponse times (IRTs); response rates changed little in the control conditions. Percentage of shocks avoided did not systematically change across conditions. In Experiment 2, the RS interval was manipulated (10, 20, and 40 s), while the SS interval (5 s) and level of sleep deprivation (48 hr) were held constant. Across RS intervals, sleep deprivation increased response rates via a shift toward brief IRTs. In addition, sleep deprivation increased the percentage of shocks avoided as an inverse function of RS intervals.

Carbohydrates, dietary fiber, and incident type 2 diabetes in older women

BACKGROUND

Dietary carbohydrates may influence the development of type 2 (non-insulin-dependent) diabetes, for example, through effects on blood glucose and insulin concentrations.

OBJECTIVE

We examined the relations of baseline intake of carbohydrates, dietary fiber, dietary magnesium, and carbohydrate-rich foods and the glycemic index with incidence of diabetes.

DESIGN

This was a prospective cohort study of 35988 older Iowa women initially free of diabetes. During 6 y of follow-up, 1141 incident cases of diabetes were reported.

RESULTS

Total grain, whole-grain, total dietary fiber, cereal fiber, and dietary magnesium intakes showed strong inverse associations with incidence of diabetes after adjustment for potential nondietary confounding variables. Multivariate-adjusted relative risks of diabetes were 1.0, 0.99, 0.98, 0.92, and 0.79 (P for trend: 0.0089) across quintiles of whole-grain intake; 1.0, 1.09, 1.00, 0.94, and 0.78 (P for trend: 0.005) across quintiles of total dietary fiber intake; and 1.0, 0.81, 0.82, 0.81, and 0.67 (P for trend: 0.0003) across quintiles of dietary magnesium intake. Intakes of total carbohydrates, refined grains, fruit and vegetables, and soluble fiber and the glycemic index were unrelated to diabetes risk.

CONCLUSION

These data support a protective role for grains (particularly whole grains), cereal fiber, and dietary magnesium in the development of diabetes in older women.

Analyzing the multiple functions of stereotypical behavior for students with autism: implications for assessment and treatment

We studied behavioral functions associated with stereotypical responses for students with autism. In Study 1, analogue functional analyses (attention, demand, no-attention, and recreation conditions) were conducted for 5 students. Results suggested that stereotypy was multiply determined or occurred across all assessment conditions. For 2 students, stereotypy was associated with positive and negative reinforcement and the absence of environmental stimulation. For 2 other students, stereotypy occurred at high levels across all experimental conditions. For the 5th student, stereotypy was associated with negative reinforcement and the absence of environmental stimulation. In Study 2, the stereotypy of 1 student was further analyzed on a function-by-function basis. Within a concurrent-schedules procedure, alternative responses were taught to the student using functional communication training. The results of Study 2 showed that similar topographies of stereotypy, based on qualitatively different reinforcers, were reduced only when differential reinforcement contingencies for alternative forms of communication were implemented for specific response-reinforcer relations. Our results suggest that the causes of stereotypy for students with autism are complex and that the presumed association between response topography and behavioral function may be less important than previously realized.

B-scan ultrasonographic findings in the stages of idiopathic macular hole

PURPOSE

To prospectively evaluate the relationship between the posterior hyaloid membrane (PHM) and the retina in eyes with idiopathic macular hole.

METHODS

Ninety-four eyes of 94 consecutive patients with macular hole underwent complete ophthalmologic examination, contact lens biomicroscopy, and B-scan ultrasonography and/or vitreoretinal surgery.

RESULTS

In 93 of 94 patients (99%), the relationship between the PHM and posterior retina could be visualized during echographic examinations or at surgery. Among these 93 patients, the PHM was detectable biomicroscopically in 36 (39%). Persistent PHM attachment to the foveola with partial separation of the PHM from the perifoveal retina was evident with ultrasonography in 5 of 6 patients (83%) with stage 1 hole and in 12 of 18 patients (67%) with stage 2 hole. When axial views were included, separation of the PHM from the perifoveal retina was evident in 13 of 13 patients (100%) with stage 1 and stage 2 hole. Separation of the PHM from the fovea and perifoveal retina with attachment to the peripapillary retina was evident with ultrasonography in 65 of 65 patients (100%) with stage 3 macular hole and pseudo-operculum and was evident biomicroscopically in 22 of the 65 patients (34%) in this group.

CONCLUSIONS

These findings suggest that high-resolution axial and paraxial ultrasonographic examination directly on the surface of the eye is more sensitive in detecting separation of the PHM from the retina than biomicroscopy in idiopathic macular holes. The perifoveal detachment of the PHM may be involved in the pathogenesis of macular holes.

Cereals, legumes, and chronic disease risk reduction: evidence from epidemiologic studies

There is growing evidence that cereals and legumes play important roles in the prevention of chronic diseases. Early epidemiologic studies of these associations focused on intake of dietary fiber rather than intake of grains or legumes. Generally, these studies indicated an inverse association between dietary fiber intake and risk of coronary artery disease; this observation has been replicated in recent cohort studies. Studies that focused on grain or cereal intake are fewer in number; these tend to support an inverse association between intake of whole grains and coronary artery disease. Studies on the association of dietary fiber with colon and other cancers have generally shown inverse relations, but whether these relations are attributable to cereals, other fiber sources, or other factors is less clear. Although legumes have been shown to lower blood cholesterol concentrations, epidemiologic studies are few and inconclusive regarding the association of legumes with risk of coronary artery disease. It has been hypothesized that legumes, in particular soybeans, reduce the risk of some cancers, but epidemiologic studies are equivocal in this regard. Overall, there is substantial epidemiologic evidence that dietary fiber and whole grains are associated with decreased risk of coronary artery disease and some cancers, whereas the role of legumes in these diseases appears promising but as yet inconclusive.

Is whole grain intake associated with reduced total and cause-specific death rates in older women? The Iowa Women's Health Study

OBJECTIVES

This study sought to determine whether nutrient-rich whole grains reduce mortality risk.

METHODS

The study included 38,740 Iowa women, aged 55 to 69 years. A food frequency questionnaire was used to obtain data on grain intake.

RESULTS

Median whole grain intake quintiles ranged from a median of 0.2 to more than 3 servings per day. Women with higher intakes had healthier lifestyles and less baseline disease. The total death rate decreased in increasing quintiles, and the pattern repeated for cancer, cardiovascular disease, and other causes combined. Adjusted for lifestyle and baseline disease, the relative hazard rate ratio for total death was about 0.85 in daily consumers of whole grain. Findings persisted in strata of baseline healthy and diseased and were not explained by dietary fiber. Rates of total mortality, but not cardiovascular disease mortality, were higher among frequent consumers of refined grain.

CONCLUSIONS

Total mortality risk was inversely associated with whole grain intake and positively associated with refined grain intake. Refined grains contributed more than 20% of energy intake, and whole grains contributed 1%. Substitution of whole for refined grain may reduce chronic disease risk in the United States.

Relation of calcium, vitamin D, and dairy food intake to ischemic heart disease mortality among postmenopausal women

To investigate whether greater intakes of calcium, vitamin D, or milk products may protect against ischemic heart disease mortality, the authors analyzed data from a prospective cohort study of 34,486 postmenopausal Iowa women 55-69 years old and without a history of ischemic heart disease who completed a dietary questionnaire in 1986. Through 1994, 387 deaths due to ischemic heart disease were documented (International Classification of Diseases, Ninth Revision, codes 410-414, 429.2). The multivariate-adjusted relative risks for the highest versus the lowest quartiles of total calcium, vitamin D, and milk product intakes were as follows: 0.67 (95% confidence interval (CI) 0.47-0.94; p for trend = 0.09) for calcium, 1.41 (95% CI 0.93-2.15; p for trend = 0.12) for vitamin D, and 0.94 (95% CI 0.66-1.35; p for trend = 0.68) for milk products. The relative risk was 0.63 (95% CI 0.40-0.98) for high dietary calcium but no supplemental calcium intake and 0.66 (95% CI 0.36-1.23) for high supplemental calcium but low dietary calcium intake. These results suggest that a higher intake of calcium, but not of vitamin D or milk products, is associated with reduced ischemic heart disease mortality in postmenopausal women, and reduced risk may be achievable whether the higher intake of calcium is attained by diet, supplements, or both.

Functional analysis and treatment of problem behavior exhibited by elementary school children

A functional analysis involving antecedent events was conducted with 4 students who had been identified as having behavior problems. Off-task behavior was measured while task difficulty and level of adult attention were manipulated during analogue sessions. Results revealed two patterns: Three students displayed higher rates of off-task behavior during difficult tasks, and 1 displayed higher rates of off-task behavior during sessions with low attention. Improved behavior was observed when students were taught an alternative behavior that matched the assessment results.

Whole-grain intake may reduce the risk of ischemic heart disease death in postmenopausal women: the Iowa Women's Health Study

BACKGROUND

A recent review of epidemiologic literature found consistently reduced cancer and heart disease rates in persons with high compared with low whole-grain intakes.

OBJECTIVE

We hypothesized that whole-grain intake was associated with a reduced risk of ischemic heart disease (IHD) death.

DESIGN

We studied 34,492 postmenopausal women aged 55-69 y and free of IHD at baseline in 1986. There were 438 IHD deaths between baseline and 1995. Usual dietary intake was determined with use of a 127-item food-frequency questionnaire.

RESULTS

Whole-grain intake in median servings/d was 0.2, 0.9, 1.2, 1.9, and 3.2 for quintiles of intake. The unadjusted rate of IHD death was 2.0/1 x 10(3) person-years in quintile 1 and was 1.7, 1.2, 1.0, and 1.4 IHD deaths/1 x 10(3) person-years in succeeding quintiles (P for trend < 0.001). Adjusted for demographic, physiologic, behavioral, and dietary variables, relative hazards were 1.0, 0.96, 0.71, 0.64, and 0.70 in ascending quintiles (P for trend = 0.02). The lower risk with higher whole-grain intake was not explained by intake of fiber or several other constituents of whole grains.

CONCLUSION

A clear inverse association between whole-grain intake and risk of IHD death existed. A causal association is plausible because whole-grain foods contain many phytochemicals, including fiber and antioxidants, that may reduce chronic disease risk. Whole-grain intake should be studied further for its potential to prevent IHD and cancer.

An Educational Program to Prepare Acute Care Nurses for a Transition to Home Health Care Nursing

This article describes a continuing education program that prepares nurses with experience in acute care nursing for the transition to home health care nursing. The program is a 12-credit hour, two semester college program consisting of 8 hours of theory and 4 hours of clinical practicum. A coalition of hospitals, home health agencies and an educational institution designed the program to maintain the economic welfare of nurses in an era of hospital layoffs, promote professional development and enhance the transition of nurses to home health nursing.

Sleep deprivation, allergy symptoms, and negatively reinforced problem behavior

We studied the relation between the presence versus the absence of sleep deprivation or allergy symptoms and the rate and function of problem behavior. Three students whose problem behavior was negatively reinforced by escape form instruction were studied across several weeks using analogue functional analyses. Our results indicated that the extraexperimental events were associated with (a) termination of instruction functioning as a negative reinforcer, (b) increased rates of negatively reinforced problem behavior, or (c) increased rates of problem behavior across all conditions.

Schedule-induced defecation by rats during ratio and interval schedules of food reinforcement

Lever pressing in rats was maintained by continuous and intermittent schedules of food while defecation was monitored. In Experiment 1, reinforcement densities were matched across variable-ratio and variable-interval schedules for three pairs of rats. Defecation occurred in all 3 rats on the variable-ratio schedule and in all 3 rats on the yoked variable-interval schedule. In Experiment 2, fixed-ratio and fixed-interval schedules with similar reinforcement densities maintained lever pressing. Defecation occurred in 3 of 4 rats on the fixed-ratio schedule and in 4 of 4 rats on the fixed-interval schedule. Almost no defecation occurred during continuous reinforcement in either experiment. These results demonstrate that defecation may occur during both ratio and interval schedules and that the inter-reinforcement interval is more important than the behavioral requirements of the schedule in generating schedule-induced defecation.

Multiresidue Gas Chromatographic Method for Determining Organochlorine Pesticides in Poultry Fat: Collaborative Study

A gas chromatographic electron capture detector method is described for the quantitative determination of organochlorine pesticide residues in poultry fat. The samples are rendered and cleaned up using automated gel permeation chromatography. The collaborative samples consisted of 10 fortified samples and one incurred residue sample, all in duplicate. Fortification levels ranged from 0.15 to 1.0 ppm for a-BHC, lindane, cis- and frans-chlordane, octachlor epoxide, o,p' and p,p'-DDT, p,p'-DDE, p,p'-TDE, hexachlorobenzene, heptachlor epoxide, dieldrin, endrin, methoxychlor, mirex, and toxaphene. The average recovery was 91.9% with a range of 81-102%. The ranges of coefficients of variation were: CVo = 3.39-14.79%; CVL = 0-16.6%; and CVx = 5.82-19.0%. The results indicate accuracy and precision comparable to other official methodology. The method has been adopted official first action.

Mineral oil vacuum distillation method for nitrosamines in fried bacon, with thermal energy analyzer: collaborative study

Nine laboratories participated in a collaborative study of a method for determining 6 nitrosamines, dimethylnitrosamine, diethylnitrosamine, dibutylnitrosamine, nitrosopiperidine, nitrosopyrrolidine, and nitrosomorpholine, in the 5-17 ppb range. The coefficients of variation for repeatability were 10.8, 8.5, 10.4, 8.5, 8.7, and 7.8% with corresponding coefficients of variation for reproducibility of 16.4, 12.0, 13.6, 10.8, 11.2, and 10.3% and recoveries of 89.6, 91.6, 84.7, 90.0, 89.6, and 88.1%, respectively. The method was adopted official first action.

Mineral Oil Vacuum Distillation Method for Nitrosamines in Fried Bacon, with Thermal Energy Analyzer: Collaborative Study

Nine laboratories participated in a collaborative study of a method for determining 6 nitrosamines, dimethylnitrosamine, diethylnitrosamine, dibutylnitrosamine, nitrosopiperidine, nitrosopyrrolidine, and nitrosomorpholine, in the 5-17 ppb range. The coefficients of variation for repeatability were 10.8, 8.5,10.4, 8.5, 8.7, and 7.8% with corresponding coefficients of variation for reproducibility of 16.4, 12.0,13.6,10.8,11.2, and 10.3% and recoveries of 89.6, 91.6, 84.7, 90.0, 89.6, and 88.1%, respectively. The method was adopted official first action.