Efficacy of washing meat surfaces with 2% levulinic, acetic, or lactic acid for pathogen decontamination and residual growth inhibition.

We compared spray washing at 55.4 °C with 2% levulinic acid to that with lactic or acetic acid for decontamination of pathogenic bacteria inoculated onto meat surfaces, and their residual protection against later growth of pathogenic bacteria. The model systems included Escherichia coli O157:H7 on beef plate, Salmonella on chicken skin and pork belly, and Listeria monocytogenes on turkey roll. In the decontamination studies, acid washes lowered recoverable numbers of pathogens by 0.6 to 1 log/cm(2) as compared to no-wash controls, and only lactic acid lowered the number of pathogens recovered as compared to the water wash. Washing with levulinic acid at 68.3 or 76.7 °C did not result in additional decontamination of E. coli. Acetic acid prevented residual growth of E. coli and L. monocytogenes, and it reduced numbers of Salmonella on chicken skin to below recoverable levels. Overall, levulinic acid did not provide as effective decontamination as lactic acid nor residual protection as acetic acid.

External concentration of organic acid anions and pH: key independent variables for studying how organic acids inhibit growth of bacteria in mildly acidic foods.

Although the mechanisms by which organic acids inhibit growth of bacteria in mildly acidic foods are not fully understood, it is clear that intracellular accumulation of anions is a primary contributor to inhibition of bacterial growth. We hypothesize that intracellular accumulation of anions is driven by 2 factors, external anion concentration and external acidity. This hypothesis follows from basic chemistry principles that heretofore have not been fully applied to studies in the field, and it has led us to develop a novel approach for predicting internal anion concentration by controlling the external concentration of anions and pH. This approach overcomes critical flaws in contemporary experimental design that invariably target concentration of either protonated acid or total acid in the growth media thereby leaving anion concentration to vary depending on the pK(a) of the acids involved. Failure to control external concentration of anions has undoubtedly confounded results, and it has likely led to misleading conclusions regarding the antimicrobial action of organic acids. In summary, we advocate an approach for directing internal anion levels by controlling external concentration of anions and pH because it presents an additional opportunity to study the mechanisms by which organic acids inhibit bacterial growth. Knowledge gained from such studies would have important application in the control of important foodborne pathogens such as Listeria monocytogenes, and may also facilitate efforts to promote the survival in foods or beverages of desirable probiotic bacteria.

Control of Listeria monocytogenes in ready-to-eat meats containing sodium levulinate, sodium lactate, or a combination of sodium lactate and sodium diacetate.

This study investigated the use of sodium levulinate to prevent outgrowth of Listeria monocytogenes in refrigerated ready-to-eat (RTE) meat products. Turkey breast roll and bologna were formulated to contain 1%, 2%, or 3% (w/w) sodium levulinate, 2% sodium lactate, a 2% combination of sodium lactate and sodium diacetate (1.875% sodium lactate and 0.125% sodium diacetate), or no antimicrobial (control). Samples of the RTE products were sliced, inoculated with 10(2) to 10(3) CFU/cm(2) of a 5-strain cocktail of L. monocytogenes, vacuum packaged, and stored at refrigeration temperature for 0 to 12 wk. Counts reached 10(8) CFU/cm(2) on control turkey roll product after 8 wk, and over 10(7) CFU/cm(2) on control bologna after 12 wk. Addition of 2% or more sodium levulinate to turkey roll and 1% or more sodium levulinate to bologna completely prevented growth of L. monocytogenes during 12 wk of refrigerated storage. A consumer taste panel with pathogen-free samples found no differences in the overall liking among the preparations of turkey roll or among preparations of bologna. These results show that sodium levulinate is at least as effective at inhibiting outgrowth of L. monocytogenes in RTE meat products as the current industry standards of lactate or lactate and diacetate, and levulinate addition does not alter the overall liking of the RTE meat products.

Interleukin-1beta induced activation of nuclear factor-kappab can be inhibited by novel pharmacological agents in osteoarthritis.

OBJECTIVES: To investigate the importance of activation of the transcription factor, nuclear factor-kappaB (NF-kappaB) by interleukin-1beta (IL-1beta) and tumour necrosis factor-alpha (TNF-alpha) in the pathogenesis of osteoarthritis (OA) and assess its suitability as a target for therapy by determining its role in the induction of the cytokine IL-6 and the degenerative enzymes, matrix metalloproteinase (MMP)-1 and MMP-3 in vitro. METHODS: Three distinct cellular models, derived from primary OA tissue, were employed, namely, fibroblast-like synoviocytes (OA-SF); co-cultures containing phenotypic macrophage-like and fibroblast-like cells (OA-COCUL); and primary OA synovial tissue explants (OA-EXP). These were treated with specific inhibitors of IL-1beta, TNF-alpha and NF-kappaB to assess their differential role in the production of pathologically relevant mediators, specifically IL-6, MMP-1, MMP-3 and the tissue inhibitor of metalloproteinases-1 (TIMP-1), which were quantified by enzyme-linked immunosorbent assay. RESULTS: Inhibition of NF-kappaB by a novel agent, RO100 at a dose of 0.1 microM, exerted significant (P < 0.05) repression of IL-6, MMP-1 and MMP-3 production in OA-SF. Notably, neither TIMP-1 production nor cell viability was significantly affected at the dose tested. These data were reproduced in OA-EXP, which might be considered as having greater physiological relevance. Interestingly, comparable efficacy was noted using IL-1beta and TNF-alpha neutralizing antibodies in OA-COCUL. CONCLUSIONS: We have demonstrated that a novel pharmacological inhibitor of NF-kappaB, RO100 inhibits pathological mediators of OA progression with equivalent efficacy as established IL-1beta and TNF-alpha neutralizing strategies. Our findings highlight a potential for developing NF-kappaB targeted therapeutics for positively regulating disease activity and improving clinical outcome in OA.

Uranium precipitation in a permeable reactive barrier by progressive irreversible dissolution of zerovalent iron.

A permeable reactive barrier (PRB) containing zerovalent iron [Fe(O)] was installed at a former uranium milling site in Monticello, UT. A large-scale column experiment was conducted at the site to test the feasibility of Fe(O) to treat U prior to installing the PRB. Effluents from the field column experiment had pH values near 7.34, moderate decreases in C(IV) and Ca concentrations, and an elevated Fe concentration (27.1 mg/L). In contrast, groundwater exiting the PRB had a pH value of 9.82, decreases in C(IV) and Ca concentrations, and a low concentration of Fe (0.17 mg/L). A geochemical model was used to explain the chemical changes that occurred in both the field column experiment and the PRB. The model simulated the systems by the progressive irreversible dissolution of Fe(O). Modeling results indicated that a longer residence time in the PRB compared with the shorter residence time in the column contributed to the disparate effluent qualities. Prior to modeling, a controlled laboratory column experiment was conducted to help evaluate the dominant chemical mechanisms by which Fe(O) removes U from aqueous solutions. Results of the laboratory column experiment indicated that only a small amount of U could be adsorbed to ferric minerals, and, therefore, this mechanism was not considered in the model.

Association of bond, market, operational, and financial factors with multi-hospital system bond issues.

Despite the growth of multi-hospital systems in the 1990s, their performance in the tax-exempt bond market has not been adequately evaluated. The purpose of this study is to compare bonds issued by multi-hospital systems to those issued by individual hospitals in terms of bond, market, operational, and financial characteristics. The study sample includes 2,078 newly issued, tax-exempt, revenue bonds between 1991 and 1997. The findings indicate that multi-hospital systems issued larger amounts of debt at a lower cost, were more likely to be insured, had higher debt service coverage and higher operating margins.

Consumer preferences for beef color and packaging did not affect eating satisfaction.

We investigated whether consumer preferences for beef colors (red, purple, and brown) or for beef packaging systems (modified atmosphere, MAP; vacuum skin pack, VSP; or overwrap with polyvinyl chloride, PVC) influenced taste scores of beef steaks and patties. To test beef color effects, boneless beef top loin steaks (choice) and ground beef patties (20% fat) were packaged in different atmospheres to promote development of red, purple, and brown color. To test effects of package type, steaks and patties were pre-treated with carbon monoxide in MAP to promote development of red color, and some meat was repackaged using VSP or PVC overwrap. The differently colored and packaged meats were separately displayed for members of four consumer panels who evaluated appearance and indicated their likelihood to purchase similar meat. Next, the panelists tasted meat samples from what they had been told were the packaging treatments just observed. However, the meat samples actually served were from a single untreated steak or patty. Thus, any difference in taste scores should reflect expectations established during the visual evaluation. The same ballot and sample coding were used for both the visual and taste evaluations. Color and packaging influenced (P<0.001) appearance scores and likelihood to purchase. Appearance scores were rated red>purple >brown and PVC >VSP>MAP. Appearance scores and likelihood to purchase were correlated (r=0.9). However, color or packaging did not affect (P>0.5) taste scores. Thus, consumer preferences for beef color and packaging influenced likelihood to purchase, but did not bias eating satisfaction.

Evaluation of carbon monoxide treatment in modified atmosphere packaging or vacuum packaging to increase color stability of fresh beef.

Our goal was to obtain > 21 days red color stability for carbon monoxide (CO)-treated beef steaks in vacuum packaging (VP). In preliminary tests, pretreatment for 24 h in a 5% CO modified atmosphere package (MAP) was needed to maintain redness after re-packaging in VP. Pressure pretreatment with 5% CO for 2 h developed redness, but was impractical for large-scale application. Color stability and microbial load were then compared after treatment of steaks in 5% CO-MAP for 24 h, then VP; 100% CO-MAP for 1 h, then VP; steaks and ground beef in 0.5% CO-MAP; and steaks and ground beef in polyvinyl chloride (PVC) wrap. Steaks remained red for 5, 6, 8 and <1-week storage at 2°C, respectively. Steaks microbial load exceeded spoilage levels (>10(6)cfu/cm(2)) at 5, 6, 7 and <2-weeks, respectively. Thus, extended color stability in VP was achieved by pretreatment with 5% CO for 24 h or 100% CO for 1 h.

Minimum sodium nitrite levels for pinking of various cooked meats as related to use of direct or indirect-dried soy isolates in poultry rolls.

The relationship between sodium nitrite level and pinking was investigated in cooked meats, as measured by panel color score, acetone extraction of NO-hemochrome, and instrumental redness values. Beef was less susceptible than poultry breast meat to nitrite-induced pinking. Minimum sodium nitrite level for pinking was 14, 4, 2, and 1 ppm for beef round, pork shoulder, turkey breast, and chicken breast, respectively. By regression analysis, minimum ppm nitrite for pinking=0.092 (ppm total pigment)+0.53 (R(2)=0.99). High levels of nitrate (>250 ppm as sodium nitrate) and nitrite (>45 ppm as sodium nitrite) were found in direct-dried (DD) soy isolates. Chicken breast rolls formulated with >2% DD soy were pink, but control rolls with 156 ppm sodium nitrate were not pink. Thus, it was concluded that nitrite was the primary pinking agent in DD soy. Indirect-dried (ID) soy isolates contained <11 ppm sodium nitrite, which was insufficient for pinking in poultry rolls.

Severity of illness and profitability: a patient level analysis.

Crafting a payment mechanism for hospitals that provides for the legitimate operating needs of efficient institutions is an enduring health policy dilemma. The Prospective Payment System used by Medicare and some other payers in the US has been criticized for not adjusting for differences in severity of illness within diagnosis-related groups (DRGs). Previous studies have examined the relationship between profitability and severity of illness at the hospital level. This study examines the relationships between severity of illness and cost, revenue, and profit at the patient level. Two measures of severity (disease stage and number of unrelated diseases) were significant predictors of cost per case, and often had better predictive power than DRGs. In most instances, payers did not compensate adequately for severity so that higher values for the severity variables resulted in financial losses for the hospital.

Issues of cost and quality: barriers to an informed debate.

Debates over health reform in the United States are hampered by a poorly informed public and misunderstandings about the concepts of quality, cost containment and their relationship to each other. This paper explores the nature and persistence of barriers to an informed public discussion of reform proposals. Those barriers are: (1) multiple definitions of quality, cost and cost containment, (2) the impact of the media on those definitions, (3) a false assumption that cost containment automatically results in diminished quality, and (4) the perceived impact of managed care and for-profit health firms on that assumption. We suggest a framework for building the understanding and knowledge base necessary to a reform of the nation's health care system.

The impact of clinical guidelines on practice patterns: doing more versus doing less.

This study examined the determinants of compliance with clinical guidelines for glucocyte colony-stimulating factor (GCSF), a biotechnology product designed to reduce postchemotherapy infections. The pattern of compliance did change over time. After the guidelines were disseminated, appropriate use of GCSF increased. However, inappropriate use also increased. Patients who were younger and had an attending physician who was an oncologist or hematologist were more likely to receive GCSF whether they met the guideline criteria or not. Our findings suggest that older patients may be treated less aggressively than others and that physicians who are the most knowledgeable about guidelines may feel the most qualified to override the guidelines when they believe they do not apply. Our findings also demonstrate that it is easier to encourage physicians to do more for patients rather than less.

Clinical decision making--what every non-clinician manager should know but was never taught.

The management of a health care system requires making decisions and establishing policies that can affect the process of patient care. Clinicians often complain that these decisions and policies are made by people without clinical training. Clinical knowledge is not a prerequisite for a career in health policy or management. Even graduates of accredited health administration programs are not required to understand the process of clinical decision making or the nature of medical practice. Much of the health services literature advocates a shared decision-making model for clinicians and managers. However, most of the literature focuses on how to involve physicians in management decision making; almost none discusses management involvement in clinical decisions. This paper briefly examines how non-clinician managers can support the clinical decision-making process and then specifies the knowledge and skills required for them to play this role.

Histology and composition of muscles from normal and callipyge lambs.

The histology and composition of muscles from normal (n = 10) and callipyge (n = 11) wether lambs was compared. Normal Rambouillet ewes were mated with callipyge Dorset rams, and their progeny were visually classified as callipyge or normal based on muscle definition in the loin and hind quarters. The muscles examined included three muscles that hypertrophy in callipyge lambs (semitendinosus, longissimus, and gluteus medius) and one muscle believed not to hypertrophy (supraspinatus). The hypertrophy-responsive muscles from callipyge lambs had a higher (P < .001) percentage of fast-twitch glycolytic (FG) fibers and lower (P < .001; P < .02 for SO in gluteus medius) percentages of slow-twitch oxidative (SO) and fast-twitch oxidative glycolytic (FOG) fibers. The diameters of the FG and FOG fibers were larger (P < .005 and P < .04, respectively) in hypertrophy-responsive muscles from callipyge lambs, but the SO fiber diameter was smaller (P < .05). Also, the protein:DNA ratio, an indicator of cell size, was greater (semitendinosus, P < .05); longissimus, P < .002; gluteus medius, P < .008) in the hypertrophy-responsive muscles from callipyge lambs. Thus, hypertrophy in callipyge lambs was, at least in part, due to fiber type changes and muscle cell enlargement. Hypertrophy was strongly associated with changes in the FG fibers, the only fiber type that increased in both proportion and average diameter in callipyge muscles. The protein:RNA ratio and RNA:DNA ratio, which are indicators of translational and transcriptional activity in the muscle cells, were not different between callipyge and normal muscles. This indicated that the accumulation of protein necessary for myofiber enlargement occurred without differences in the translational or transcriptional activity of callipyge muscle.

Role of clinical evaluation in academic medical centers: results of a national survey.

BACKGROUND: It is widely acknowledged that academic medical centers (AMCs) must be committed to appropriate resource use and to the clinical evaluation research needed to accomplish this goal. The authors report the results of a national survey and series of site visits to further elucidate the role of centralized mechanisms for evaluating clinical practice, called clinical evaluation units (CEUs). A CEU is characterized by a separate operating unit with a physician director on at least a half-time basis complemented by data analysts, information system specialists, or other technical staff. METHOD: In April 1993, the authors mailed a survey instrument to the 60 hospitals that were members of the University Hospital Consortium (UHC) and to 28 non-UHC teaching hospitals. After four follow-up mailings and telephone reminders, a 69% response rate (61 responses) was achieved. The survey instrument highlighted areas such as the environment in which the hospitals operated, the structure and organization of clinical evaluation, the process of how these activities were carried out, and the outcomes from the CEUs. RESULTS: Twenty-two respondents had centralized mechanisms that met the authors' definition of a CEU. Support for most CEUs came from hospital administrations and not from medical school deans. An alternative structure emerged from the analysis: 18 respondents indicated that they did not have CEUs but that clinical evaluation activities were integrated into the medical staff hierarchy and dispersed throughout departments that reported to a physician executive. CONCLUSION: The discipline of clinical evaluation is in its infancy in teaching institutions. Many AMCs do not have a coordinated program of clinical evaluation; others are just starting. Clinical evaluation must become integrated into medical education and hospital operations to serve as one aspect of academic medicine's response to health care reform.

Clinical evaluation units: a research agenda.

A new model for evaluating quality rests on the tripod of outcomes research, practice pattern analysis, and the tenets of continuous quality improvement. The hospital-based locus for this tripod could be clinical evaluation units. This article describes the conceptual framework, study design, and research challenges associated with an ongoing project whose purpose is to assess the current status of these clinical evaluation units in academic medical centers nationwide.

Hospital markups: responses to environmental pressures in Pennsylvania.

The practice of cost shifting has stirred interest in hospital pricing policy. This study examined the determinants of the markup ratio, a summary measure of the hospital's pricing policy, in Pennsylvania acute care hospitals. The results indicate that severity of illness and the proportion of revenue earned from Medicare and Medicaid were the most important factors influencing markups. Other significant factors included extensive teaching activities and county per capita income.

Cost accounting supports clinical evaluations.

This article describes how a hospital cost accounting system was used to evaluate the financial impact of the use of a new and expensive drug at a 700-bed academic medical center.

The impact of intra-DRG severity of illness on hospital profitability: implications for payment reform.

We examined the relationship between variations in intra-DRG severity of illness classifications and hospital profitability. Unlike in previous studies, we created a direct hospital-level measure of severity, formed from MedisGroup severity scores. We estimated separate regression equations for total margin, operating margin, net revenue per admission, and expense per admission. We examined data for 201 Pennsylvania hospitals and found that hospital profits were inversely related to the severity of illness index. Expense per admission was positively related to severity; however the relationship between severity and net revenue per admission was not significant. The results suggest that hospitals with a more severe case mix may not recover the full costs of providing services. Thus payment reform should include adjustments for severity of illness.