Visual Immunoprecipitate Assay (VIP) for Listeria monocytogenes and Related Listeria Species Detection in Selected Foods: Collaborative Study

Six foods representing a variety of food products were analyzed by the Assurance Listeria polyclonal enzyme immunoassay (EIA) and by either the Bacteriological Analytical Manual or the U.S. Department of Agriculture culture method for detecting Listeria monocytogenes and related Listeria species. Samples of each food type, at each inoculation level, were analyzed simultaneously by both methods. A total of 19 laboratories representing federal government agencies and private industry in the United States and Canada participated. Food types were inoculated with Listeria species including L. monocytogenes, with the exception of 3 lots of green beans, which were naturally contaminated. During this study, 1764 samples and controls were analyzed and confirmed, of which 492 were positive and 947 were negative by both methods. There were 159 samples that were positive by culture method but negative by the EIA and 188 that were negative by culture method but positive by EIA. Twenty-two samples were negative by EIA and by culture method but confirmed positive when Assurance selective enrichment broths were subcultured to selective agar. The Assurance polyclonal EIA for detecting L. monocytogenes and related Listeria species in foods has been adopted first action by AOAC INTERNATIONAL.

Dry Rehydratable Film Method for Enumerating Confirmed Escherichia coli in Poultry, Meats, and Seafood: Collaborative Study

A rehydratable dry-film plating method for Escherichia coli, the Petrifilm E. coli/Coliform (EC) Count Plate in foods, has been compared with the AOAC INTERNATIONAL most probable number (MPN) method. Eleven laboratories participated in the collaborative study. Three E. coli levels in 8 samples each of frozen raw ground turkey, frozen raw ground beef, and frozen cooked fish were tested in duplicate. Mean log counts for the Petri film plate procedure were not significantly different from those for the MPN procedure for cooked fish samples inoculated with low or high inocula levels, for samples of raw turkey inoculated at medium level, and for beef inoculated at low, medium, and high levels. Repeatability and reproducibility vari ances of the Petrifilm EC Plate method recorded at 24 h were as good as or better than those of the MPN method. The dry rehydratable film method for enumerating confirmed E. coli in poultry, meats, and seafood has been adopted first action by AOAC INTERNATIONAL.

High-Sensitivity Dry Rehydratable Film Method for Enumeration of Coliforms in Dairy Products: Collaborative Study

A dry-film coliform count plate that is inoculated with 5 mL sample was compared with the Violet Red Bile Agar plate method in a collaborative study by 18 laboratories. Products analyzed were 2% milk, chocolate milk, cream, vanilla ice cream, cottage cheese, and cheese. Collaborators tested blind duplicate uninoculated samples and samples inoculated at low, medium, and high level. Significantly (P< 0.05) higher numbers of coliforms were recovered by the dry-film method from 2% milk samples at the 3 inoculum levels, the chocolate milk at the low- and high-inoculum levels, and the cream at the high-inoculum level. Significantly higher counts were obtained by the agar method for cottage cheese samples at the low-inoculum level. The repeatability standard deviation for the dry-film method was significantly higher for the high-inoculum level chocolate milk sample and the medium-inoculum level cottage cheese. The same statistic was significantly higher for the agar method at all 3 inoculum levels in the 2% milk and the medium-inoculum level cream. The high-sensitivity dry rehydratable film method for enumeration of coliforms in dairy products has been adopted first action by AOAC INTERNATIONAL.

Assurance Polyclonal Enzyme Immunoassay for Detection of Listeria monocytogenes and Related Listeria Species in Selected Foods: Collaborative Study

Six foods representing a variety of food products were analyzed by the Assurance Listeria polyclonal enzyme immunoassay (EIA) and by either the Bacteriological Analytical Manual or the U.S. Department of Agriculture culture method for detecting Listeria monocytogenes and related Listeria species. Samples of each food type, at each inoculation level, were analyzed simultaneously by both methods. A total of 19 laboratories representing federal government agencies and private industry in the United States and Canada participated. Food types were inoculated with Listeria species including L. monocytogenes, with the exception of 3 lots of green beans, which were naturally contaminated. During this study, 1764 samples and controls were analyzed and confirmed, of which 492 were positive and 947 were negative by both methods. There were 159 samples that were positive by culture method but negative by the EIA and 188 that were negative by culture method but positive by EIA. Twenty-two samples were negative by EIA and by culture method but confirmed positive when Assurance selective enrichment broths were subcultured to selective agar. The Assurance polyclonal EIA for detecting L. monocytogenes and related Listeria species in foods has been adopted first action by AOAC INTERNATIONAL.

3M™ Petrifilm™ Enterobacteriaceae Count Plate Method for Enumeration of Enterobacteriaceae in Selected Foods: Collaborative Study

The practice of detecting and enumerating all oxidase-negative, glucose-fermenting-Gram-negative rods (i.e., the family Enterobacteriaceae) isused to indicate unsanitary or inadequate food processing conditions. The objective of this interlaboratory collaborative study was to evaluate and compare the methods described in Standard Methods for the Examination of Dairy Products (SMEDP) and the Compendium of Methods for the Microbiological Examination of Foods (Compendium) with a commercial product, the 3M™ Petrifilm™ Enterobacteriaceae Count Plate, for the recovery of Enterobacteriaceae in foods. Six foods—cheddar cheese, milk, flour, frozen prepared meals, frozen broccoli, and nut pieces—were analyzed for Enterobacteriaceae by 12 collaborating laboratories. For each food tested, the collaborators received 8 blind test portions consisting of a control test portion and 3 levels of inoculated test portion, each in duplicate. Each test portion was tested by the Petrifilm Enterobacteriaceae Count Plate method as well as the SMEDP or Compendium methods. The precision estimates (repeat-ability or within-laboratory variation, and reproducibility or between-laboratory variation) were calculated with standard statistical techniques.

Dry Rehydratable Film Method for Rapid Enumeration of Coliforms in Foods (3M™ Petrifilm™ Rapid Coliform Count Plate): Collaborative Study

A rehydratable dry-film plating method for coliforms in foods, the 3M™ Petrifilm™ Rapid Coliform Count plate method, was compared with the U.S. Food and Drug Administration's Bacteriological Analytical Manual method for nondairy foods and the American Public Health Association's Standard Methods for the Examination of Dairy Products (SMEDP) method for dairy foods. Six food types, vanilla ice cream, cheddar cheese, fresh refrigerated uncooked pasta, wheat flour, prepared frozen macaroni and cheese, and frozen hash browns, were analyzed for coliforms by 11 collaborating laboratories. For each food product tested, the collaborators received 8 blind samples consisting of a control sample and 3 levels of inoculated sample, each in duplicate. The mean log counts for the methods were comparable. The repeatability and reproducibility variances of the Petrifilm Rapid Coliform Count method at 14 and 24 h were not significantly different from those of the standard methods.

VIDAS® Enzyme-Linked Immunofluorescent Assay for Detection of Listeria in Foods: Collaborative Study

The VIDAS LIS method and the traditional culture methods for detection of Listeria species in food were evaluated in a multilaboratory comparative study. The 6 foods tested were either naturally contaminated or inoculated with 3 different concentrations of Listeria. Results for each food and each contamination level with the VIDAS LIS method were as good as or better than those obtained with the traditional culture method. Of 1558 samples tested, 935 were positive: 839 by the VIDAS method and 809 by standard culture methods. Overall false negative rates were 10.3 and 13.5% for the VIDAS LIS and culture methods, respectively. The false positive rate for the VIDAS LIS assay was 1.4% based on 9 VIDAS LIS positive assays that did not confirm positive by isolation of Listeria. The agreement between the VIDAS LIS and culture methods for all samples tested was 86%.

A multicentre, UK, retrospective, observational study to assess the effectiveness of insulin glargine 300 units/ml in treating people with Type 1 diabetes mellitus in routine clinical practice (SPARTA)

AIM

To conduct an open-label study to provide UK real-world evidence regarding the use of insulin glargine 300 units/ml (U300) in people with Type 1 diabetes mellitus.

METHODS

People with Type 1 diabetes who had been prescribed U300 ≥6 months before data collection and had HbA_1c levels recorded within 3 months prior to U300 (baseline) were included. The primary endpoint was change in HbA_1c from baseline to month 6 after U300 initiation. Other endpoints included number of documented hypoglycaemic and diabetic ketoacidosis episodes, and change in daily basal insulin dose.

RESULTS

A total of 298 people with Type 1 diabetes were included [mean age 42.1 years, mean HbA_1c 79 mmol/mol (9.4%)]. After U300 initiation, the mean reduction in HbA_1c from baseline to month 6 was -4 mmol/mol (-0.4%; P<0.001; n=188). The total daily basal insulin dose at 6 months was 1.3 units higher than at the time of U300 initiation (P<0.001; n=275) but was not significantly different from the prior basal insulin dose. There was no clinically significant difference in weight between baseline and month 6 [mean difference +0.7 kg, 95% CI -0.1, 1.5; P=0.084; n=115). During the 6 months before and after U300 initiation, severe hypoglycaemic episodes were documented for 6/298 and 4/298 participants. Diabetic ketoacidosis episodes requiring Accident and Emergency department visits or hospitalization were documented for 4/298 and 6/298 participants, before and after U300 initiation, respectively.

CONCLUSIONS

In people with Type 1 diabetes, a change in basal insulin to U300 was associated with clinically and statistically significant HbA_1c improvements, without significant changes in basal insulin dose and weight. Documented severe hypoglycaemia episodes and diabetic ketoacidosis requiring Accident and Emergency department visits or hospitalization were low and similar before and after U300 initiation.

The high cost to health and social care of managing falls in older adults living in the community in Scotland

Background and aims

Estimate costs for health and social care services in managing older people in the community who fall.

Method and results

Analyses of predominantly national databases using cost of illness methodologies. In Scotland, 294,000 (34%) of people over 65 years and living in the community fall at least once a year. Of these 20%, almost 60,000 people contacted a medical service for assistance. There were almost 30,000 attendances at GP practices, over 36,100 calls to the Scottish Ambulance Service and 46,816 people presenting at A&E, with 16,549 admitted, 30% with a hip fracture. Mortality was high, 7% during the hospital stay, rising to over 12% at 1 year. Over 20% of patients were unable to return to their homes. Associated costs were over £470 million, with 60% incurred by social services, mainly providing long-term care. Cost per person falling was over £1720, rising to over £8600 for those seeking medical assistance. A hip fracture admission cost £39,490, compared with £21,960 for other falls-related admissions.

Conclusions

Transparent, robust cost information demonstrates the substantial burden of falls for health and social care services and should be a driver for implementing evidence-based interventions to reduce falls.

A Light-Scattering Study of Lysolecithin Sols

Sols of four samples of lysolecithin have been studied by means of a light-scattering apparatus. The results of a large number of measurements have been analysed statistically. They indicate that the mean molecular weight of the micelles in the sols is 92,400, the experimental error in this estimate being 7 per cent.

Predictors of in-hospital mortality following operative management of hip fractures

OBJECTIVE

To identify predictors of in-hospital mortality and hospital stay following hip fractures.

DESIGN

Retrospective cohort study of 185 consecutive patients.

SETTING

Tertiary Care University Hospital.

PARTICIPANTS

Individuals requiring operative treatment of a proximal femoral fracture excluding those individuals < 50 years old, with femoral head or subtrochanteric fractures, and significant co-morbidity.

OUTCOMES

In-hospital mortality and length of hospital stay (days).

RESULTS

116 patients met the inclusion criteria. Predictors of in-hospital mortality from logistic regression analysis included male gender (odds ratio with 95% CI: 5.5, 1.5-20.5), admission from a long term care facility (5.5, 1.4-22.6), age greater than 90 years (4.5, 0.9-22.1), and living at home with support (0.2, 0.03-0.9). Predictors of hospital stay from multivariate regression analysis in order of magnitude included presence of a post-operative complication (odds ratio with 95% CI: 14.1, 4.7-44), living at home with support (3.4, 1.3-8.9) and older age (> 85 years) (2.7, 1.0-7.3). Moreover, confusion, urinary tract infections and decubitus ulcers accounted for greater than 50% of all complications encountered. A trend between the number of positive predictors and length of hospital stay was observed.

CONCLUSIONS

Elderly individuals admitted from a long term care facility are at high risk of mortality following operative fixation of hip fractures. Early recognition and aggressive management of post-operative complications such as confusion, urinary tract infections and decubitus ulcers through careful patient monitoring may decrease hospital stays in those that survive.

An investigation of condom use by frequency of sex

OBJECTIVES

To examine the association between condom use and frequency of sex across sexual partner types.

METHODS

Data were collected from African American drug users residing in Washington, DC. Participants were asked to provide the first name of the last three partners with whom they had had vaginal sex, to define the type of relationship, the number of times they had had vaginal sex in the last 30 days with each partner, and whether they had used a condom during their last sexual encounter with each partner. Condom use was examined by frequency of sex in the past 30 days controlling for partner type.

RESULTS

Frequency of sexual encounters varied by partner type. The largest number of sexual encounters was with casual partners, followed by commercial and primary partners, respectively. Within partner types, participants had sex most frequently with primary partners. Condom use was lowest within primary partner relationships. Regardless of partner type, condom use varied consistently depending on the frequency of sex with the same partner.

CONCLUSIONS

Condom use is related to the frequency of sex between partners when partner type is controlled. The association between frequency of sex and condom use is independent of partner type, suggesting that partner type may become less influential in determining condom use as the frequency of sex increases. This finding suggests that contextual factors determining condom use go beyond partner type designations and include other relationship variables.

The acceptability of a computer HIV/AIDS risk assessment to not-in-treatment drug users

The purpose of this paper is to report the results of a study assessing the acceptability of a computer HIV risk assessment instrument administered to not-in-treatment drug users. The study asked three questions related to acceptability: (1) are drug users comfortable responding to HIV risk questions using the computer assessment; (2) do drug users feel that they possess the requisite skill to respond to questions using a computer; and (3) do drug users believe that the responses they provide using the computer assessment will remain private and confidential. This study differs from other assessments of the acceptability of computer assisted data collection in that the population of interest has only limited education and interaction with computers. Furthermore, the study was implemented under field conditions. To conduct the study, an existing HIV risk assessment instrument was adapted for use with the computer. Only slight modifications were made to the content of the instrument. To facilitate data collection with this population, audio enhancement and touch screen were used. Three scales measuring comfort, skill and perceived privacy were developed. Results of analysis showed that drug users are comfortable responding to an HIV risk assessment using computer assisted interviewing. Drug users also perceived that they possessed the requisite skill to successfully complete the interview. And, study participants reported that they believed that their responses using the computer interview would remain private and confidential. Only minor differences in scale scores based on sociodemographic characteristics were found among study participants. Implications of the findings are discussed.

Mutations in RNA polymerase II and elongation factor SII severely reduce mRNA levels in Saccharomyces cerevisiae

Elongation factor SII interacts with RNA polymerase II and enables it to transcribe through arrest sites in vitro. The set of genes dependent upon SII function in vivo and the effects on RNA levels of mutations in different components of the elongation machinery are poorly understood. Using yeast lacking SII and bearing a conditional allele of RPB2, the gene encoding the second largest subunit of RNA polymerase II, we describe a genetic interaction between SII and RPB2. An SII gene disruption or the rpb2-10 mutation, which yields an arrest-prone enzyme in vitro, confers sensitivity to 6-azauracil (6AU), a drug that depresses cellular nucleoside triphosphates. Cells with both mutations had reduced levels of total poly(A)+ RNA and specific mRNAs and displayed a synergistic level of drug hypersensitivity. In cells in which the SII gene was inactivated, rpb2-10 became dominant, as if template-associated mutant RNA polymerase II hindered the ability of wild-type polymerase to transcribe. Interestingly, while 6AU depressed RNA levels in both wild-type and mutant cells, wild-type cells reestablished normal RNA levels, whereas double-mutant cells could not. This work shows the importance of an optimally functioning elongation machinery for in vivo RNA synthesis and identifies an initial set of candidate genes with which SII-dependent transcription can be studied.

Role of cAMP-dependent protein kinase in cAMP-mediated vasodilation

In this study, the role of adenosine 3',5'-cyclic monophosphate (cAMP)-dependent protein kinase A (PKA) in cAMP-dependent relaxation was assessed in the isolated-perfused rat lung using a PKA inhibitor, Rp-cAMPS, 8-bromo-cAMP (8-BrcAMP), and the diterpene activator of adenylate cyclase (AC), forskolin (FSK). A role for K+ channels was also assessed with the nonselective K+ channel blocker, tetraethylammonium (TEA, 10 mM), and an ATP-sensitive K+ channel inhibitor, glibenclamide (GLI, 100 microM). Both 8-BrcAMP (0.1-1.0 mM) and RSK (0.1-10 microM) dose-dependently attenuated the peak pressor response to alveolar hypoxia (HPR). Rp-cAMPS potentiated the HPR and attenuated 8-BrcAMP-mediated vasodilation but had no effect on FSK-mediated vasodilation. FSK-mediated vasodilation was not mimicked by 1,9-dideoxy-FSK, which is biologically inactive on AC but alters K+ channels identically to FSK, nor was it attenuated by the platelet-activating factor antagonist SRI 63-441 or the cyclooxygenase inhibitor indomethacin. TEA, but not GLI, attenuated FSK-mediated vasodilation. Similarly, TEA attenuated 8-BrcAMP-mediated vasodilation. These results support roles for PKA and indirect gating of a non-ATP-sensitive K+ channel in mediating cAMP-dependent pulmonary vasodilation.

IgA deficiency in shar-pei dogs

Two shar-pei puppies examined because of signs of sinopulmonary disease, one of which also had skin disease, had deficient IgA concentrations. Deficient serum IgA concentrations also were confirmed in 30 of 39 (76.9%) clinically normal adult dogs in two colonies of shar-peis. Both courses of disease--sinopulmonary signs and chronic skin disease and a benign clinical course--have been reported in human patients with IgA deficiency. Thus, the shar-pei might be an appropriate model for studying the immunopathology of IgA deficiency in man.

The pharmacokinetics and dynamics of oxprenolol: a simulation study with six subjects

Experimental results of plasma concentration determinations and lowering of exercise heart rate for six subjects taking a conventional tablet and a sustained release preparation of oxprenolol have been analysed by a comprehensive computer simulation model. Individual plasma values were simulated using a lest squares procedure and the results were applied to evaluate individual release patterns following dosage with the sustained release preparation. Application of the model to the lowering of exercise heart rate indicated that the response is in a steady state with the plasma values and that the response-concentration relation is of the saturable, Emax, type. The parameters for this were evaluated for each subject for the results after a dose of a conventional tablet. These parameters were applicable to the results after dosage with a sustained release preparation. The method should be applicable to other sustained release preparations.

Light scattering studies of the solubilization of some esters of p-aminobenzoic acid by lysophosphatidylcholine

Light scattering equipment has been constructed using a vertically polarized helium-neon laser and a phase-sensitive detection system. The apparatus has been used to determine the micellar weight of lysophosphatidylcholine (LPC), giving values of 1.33 x 105 in water and 1.47 x 105 in 0.05 M sodium chloride; the sols showed some degree of polydispersity. The light scattering apparatus has also been used to study the solubilization by LPC of three n-alkyl esters of paraminobenzoic acid. These compounds caused a considerable increase in the scattered light, particularly at higher LPC concentrations.