High Pressure Liquid Chromatographic Determination of Glycyrrhizic Acid or Glycyrrhizic Acid Salts in Various Licorice Products: Collaborative Study

A collaborative study determining glycyrrhizic acid or glycyrrhizic acid salts content of various licorice products has been conducted using high pressure liquid chromatography (HPLC). Five samples containing various concentrations of glycyrrhizic acid were analyzed in blind replicates by 8 collaborators. The results indicate excellent repeatability and reproducibility with coefficients of variation less than 7.5%. In addition, this method allows the determination of glycyrrhizic acid in less than 15 min compared with 3 days for the conventional gravimetric and colorimetric methods. The method has been adopted official first action.

The effects of demographics, functioning, and perceptions on the relationship between self-reported and objective measures of driving exposure and patterns among older adults

The exploratory study reported here was intended to examine: how strongly subjectively reported driving avoidance behaviors (commonly referred to as self-regulation) and exposure were related to their objectively measured counterparts and whether it depended on the specific behavior; the extent to which gender and age play a role in the association between subjectively reported driving avoidance behaviors and exposure and their objectively measured counterparts; and the extent to which demographics, health and functioning, driving-related perceptions, and cognition influence the association between subjective and objective driving avoidance behaviors overall. The study used data from the Longitudinal Research on Aging Drivers (LongROAD) study, a multisite, prospective cohort study designed to generate empirical data for understanding the role of medical, behavioral, environmental, and technological factors in driving safety during the process of aging. Objective driving measures were derived from GPS/datalogger data from 2131 LongROAD participants' vehicles. The corresponding subjective measures came from a comprehensive questionnaire administered to participants at baseline that asked them to report on their driving exposure, patterns, and other aspects of driving. Several other variables used in the analyses came from the comprehensive questionnaire and an inperson clinical assessment administered to participants at baseline. A series of simple linear and logistic models were fitted to examine the relationship between the subjective and objective driving measures of interest, and a multivariable analysis was conducted to examine the potential role of selected factors in the relationship between objective and subjective driving avoidance behaviors. Results of the models are presented and overall findings are discussed within the context of the existing research literature.

Metabolism, nitrogen excretion, and heat shock proteins in the central mudminnow (Umbra limi), a facultative air-breathing fish living in a variable environment

The central mudminnow ( Umbra limi (Kirtland, 1841)) is a continuous, facultative air-breathing freshwater fish found in swamps of central Canada and northeastern USA. The first goal of this field and laboratory-based study was to characterize the physicochemical conditions of mudminnow habitat during the summer. Our second goal was to determine the metabolic, stress response, and nitrogen excretion strategies of this fish following variations in water temperature, dissolved oxygen, external ammonia, and short-term periods of air exposure. We report profound diurnal fluctuations in water temperature (13–31 °C), dissolved oxygen (2%–159% air saturation), and ammonia levels (10–240 μmol·L−1) in habitat of central mudminnow measured on three dates at six different sites over 24 h. The central mudminnow does not induce urea synthesis as a mechanism of ammonia detoxification, either in response to emersion (6 or 20 h) or elevated external ammonia (10 mmol·L–1). Acute exposure to high temperature (~31 °C), aquatic hypoxia, or air resulted in significant increases in blood glucose and liver heat shock protein (Hsp) 70 and hypoxia also caused an increased reliance on anaerobic metabolism. This is the first description of the heat shock response in a facultative air-breathing fish following either hypoxia or air exposure. These metabolic and molecular responses are part of a strategy that allows the mudminnow to thrive in extremely variable freshwater environments.

Incidence of cleft palate fistula: an institutional experience with two-stage palatal repair

The purpose of this study was to determine the incidence of cleft palatal fistula in a series of nonsyndromic children treated at the authors' institution. This retrospective analysis of 103 patients with cleft palate treated by five surgeons between 1982 and 1995 includes 60 boys and 33 girls, whose median age was 18.4 months at the time of surgery. The median length of follow-up was 4.9 years after primary palatoplasty. Cleft palatal fistula was defined as a failure of healing or a breakdown in the primary surgical repair of the palate. Intentionally unrepaired fistulas of the primary and secondary palate were excluded. Extent of clefting was described according to the Veau classification. Statistical examination of multiple variables was performed using contingency table analysis, multivariate logistic regression, and the Wilcoxon rank sum test. The incidence of cleft palatal fistula in this series was 8.7 percent. All of these fistulas were clinically significant. The rate of fistula recurrence was 33 percent. The incidence of cleft palatal fistula when compared by Veau classification was statistically significant, with nine fistulas occurring in patients with Veau 3 and 4 clefts and no fistulas occurring in patients with Veau 1 and 2 clefts (p = 0.0441). No significant differences between patients with and without fistulas were identified with respect to operating surgeon, patient sex, patient age at palatoplasty, type of palatoplasty, and use of presurgical orthopedics or palatal expansion. All three recurrent fistulas occurred in the anterior palate, two in patients with Veau class 3 clefts and one in a patient with a Veau class 4 cleft. The low rate of clinically significant fistula was attributed to early delayed primary closure, with smaller secondary clefts allowing repair with a minimum of dissection and disruption of vascularity.

Interspecific and intraspecific variation in proximate, mineral, and fatty acid composition of milk in Old World fruit bats (Chiroptera: Pteropodidae)

We examine the effect of body mass on milk composition among Old World fruit bats, including Pteropus pumilus (0.175 kg), Pteropus rodricensus (0.265 kg), Pteropus hypomelanus (0.571 kg), and Pteropus vampyrus (1.133 kg). We describe intra- and interspecific differences in the proximate composition of milk among these four species and the minerals and fatty acids in the milk of the latter two species. There were no differences between species in the concentrations of dry matter, fat, or lactose in milk. However, there were significant, although small, differences in the protein content of milk among species, with protein being significantly greater in P. rodricensus than in P. pumilus and P. hypomelanus and protein being significantly less in P. hypomelanus than in P. rodricensus and P. vampyrus. There were no differences in mineral content between P. hypomelanus and P. vampyrus in milk minerals, but minor differences were evident in fatty acids 12:0, 14:0, 18:0, 18:1n11, and 18:2n6. Our findings suggest that milk composition is relatively constant across lactation for most proximate, mineral, and fatty acid components. We found a significant increase in dry matter and energy across lactation in the concentration of dry matter and energy in P. pumilus and fat in P. hypomelanus. In P. hypomelanus, we found a significant increase in the concentration of fatty acids 10:0 and 20:1n9 and a significant decrease in Iso15 and 20:1n7. No other differences associated with day of lactation were found. These findings suggest that milk composition is generally similar within the genus Pteropus, despite a 6.5-fold difference in body mass between species that we evaluated.

Reduction of unsafe eating in a patient with esophageal stricture

Previous research has demonstrated the efficacy of behavioral interventions in teaching self-feeding skills as well as in reducing inappropriate self-feeding behavior. The purpose of this study was to extend previous research on the use of prompting and reinforcement in reducing unsafe eating behaviors to the treatment of an adolescent with developmental disabilities and esophageal stricture. A behavioral assessment and treatment using prompting and reinforcement were shown to be effective in decreasing bite rate, decreasing bite size, and increasing the number of chews per bite.

Treating hypertension. Are the right drugs given to the right patients?

OBJECTIVE

To evaluate whether physicians are prescribing antihypertensive drugs appropriately and according to the recommendations of the Canadian Hypertension Society.

DESIGN

Retrospective cohort study.

SETTING

Family medicine teaching clinic in Montreal.

PARTICIPANTS

A cohort of 183 patients followed between 1993 and 1995. Of 350 patients registered at the clinic, 167 were excluded because diagnosis of hypertension was not supported by chart review, their charts contained insufficient information, they were pregnant or younger than 18 years, or they had secondary hypertension and complex medical conditions.

MAIN OUTCOME MEASURES

The dependent variable was the antihypertensive medication. Independent variables were age and sex of patients, duration of hypertension, total number of visits and number of visits for hypertension, number of physicians consulted at the clinic, associated medical conditions, diagnosis of target organ damage, blood pressure readings, and associated medications.

RESULTS

Diuretics were prescribed most frequently (45.9%). Angiotensin-converting enzyme (ACE) inhibitors ranked second (28.4%), followed by calcium channel blockers (26.2%) and beta-blockers (18.0%). Age, sex, duration of hypertension, and blood pressure readings were not associated with medications. Prescription of beta-blockers was strongly associated with previous myocardial infarction, but not with diagnosis of angina pectoris. Patients with contraindications to beta-blockers were less likely to receive them and more likely to receive calcium channel blockers. Only 32% of diabetic patients received ACE inhibitors.

CONCLUSION

Results suggest that some prescriptions for antihypertensive medications are inappropriate, but that physicians are following some of the Canadian Hypertension Society's recommendations. A better understanding of physicians' prescribing behaviours could help target continuing education interventions to improve prescribing for hypertension.

Cloning, sequencing, and expression in Escherichia coli of the D-hydantoinase gene from Pseudomonas putida and distribution of homologous genes in other microorganisms

Pseudomonas putida DSM 84 produces N-carbamyl-D-amino acids from the corresponding D-5-monosubstituted hydantoins. The gene encoding this D-hydantoinase enzyme was cloned and expressed in Escherichia coli. The nucleotide sequence of the 1.8-kb insert of subclone pGES19 was determined. One open reading frame of 1,104 bp was found and was predicted to encode a polypeptide with a molecular size of 40.5 kDa. Local regions of identity between the predicted amino acid sequence and that of other known amidohydrolases (two other D-hydantoinases, allantionase and dihydroorotase) were found. The D-hydantoinase gene was used as a probe to screen DNA isolated from diverse organisms. Within Pseudomonas strains of rRNA group I, the probe was specific. The probe did not detect D-hydantoinase genes in pseudomonads not in rRNA group I, other bacteria, or plants known to express D-hydantoinase activity.

Importance of neutralizers in the stripping fluid in a simulated healthcare personnel handwash

The Food and Drug Administration (FDA) healthcare personnel handwash procedure allows for the use of a non-neutralizing stripping fluid after washing with an antimicrobial handwash product. The antimicrobial in the handwash product can remain active up until the time of neutralization or plating. A modified healthcare personnel handwash procedure using a pigskin substrate and a 4% chlorhexidine gluconate handwash product was used to demonstrate the need for a neutralizer in the stripping fluid. When tests were run with and without neutralizers in the dilution blanks, but with adequate neutralizers in the stripping fluid, there were no significant differences (p greater than .05) between results obtained after five washes or after each wash. When tests were run with a non-neutralizing stripping fluid, significant differences were noticed in the first and the fifth wash (p less than .05), and in the presence or absence of neutralizers in the dilution blanks (p less than .05). The data generated indicate that in order to determine the true activity of an antimicrobial handwash product, an adequate neutralizer should be incorporated into the stripping fluid and not just the dilution media. They also suggest that neutralizer carry-over from the stripping fluid is not a valid concern.

The effects of surfactant systems and moisturizing products on the residual activity of a chlorhexidine gluconate handwash using a pigskin substrate

A series of handwashing experiments using a pigskin substrate and Serratia marcescens as the contaminant compared the residual activity of a chlorhexidine detergent handwash product alone and in combination with anionic and nonionic-based moisturizing products and surfactant systems. The anionic based moisturizing products and the anionic surfactant system almost completely destroyed the residual antibacterial activity of the chlorhexidine, while the nonionic-based products had minimal effect.

Slow continuous hemodialysis for the management of complicated acute renal failure in an intensive care unit

This paper describes a simple system for the performance of slow continuous hemodialysis (SCHD) as a means of treating difficult and complicated cases of oliguric acute renal failure. The method, which employs access to the circulation via a double-lumen central venous catheter and a BSM 22 blood systems module, can be performed safely in the intensive care unit of a general hospital if closely supervised by a trained nephrologist. The results of treating 16 consecutive cases of complicated acute renal failure in a large general hospital without a hemodialysis unit are described. The method, whose simplicity makes it suitable for intensive care unit nurses without previous hemodialysis training, was not associated with any serious accidents or complications, and was tolerated well by even the most critically ill and hemodynamically unstable patients. The advantages of this approach over more traditional continuous arteriovenous hemofiltration (CAVH) are discussed.

A chicken sex-limited protein that crossreacts with the fourth component of complement

Plasma samples from more than 300 inbred chickens were screened by using an immunofixation technique with antibody against the fourth component of complement (C4) from humans. Precipitation patterns of plasma from adult male and sexually immature birds, either male or female, were identical. Plasma from egg-laying hens demonstrated a distinctly different precipitation pattern compared with plasma of other birds, with one additional band appearing 14 to 9 days before production of the first egg. The banding pattern could not be induced in males by progesterone injection and remained unchanged in molted female birds.

Pathogenicity of Eikenella corrodens in humans

Eikenella corrodens is resident flora of the normal adult human oral cavity. Four cases of verified infection and previous case reports of infections caused by this organism were reviewed and analyzed. Rarely has this bacillus been found as the sole isolate to initiate infection in the host with normal immune status. In the immunocompromised host, this organism was observed as the sole isolate in cases of persistent empyemas and/or overwhelming pneumonias with bacteremias. The potential of the organism singly to perpetuate an established infection appears real. In the immunocompromised patients such potentials are accentuated and can result in fulminant pulmonary infections and death. The finding of E corrodens in an infection site of a compromised patient should indicate specific therapy.

Purification and properties of the hexosaminidase A-activating protein from human liver

Human liver extracts contain an activating protein which is required for hexosaminidase A-catalysed hydrolysis of the N-acetylgalactosaminyl linkage of G(M2) ganglioside [N-acetylgalactosaminyl-(N-acetylneuraminyl) galactosylglucosylceramide]. A partially purified preparation of human liver hexosaminidase A that is substantially free of G(M2) ganglioside hydrolase activity is used to assay the activating protein. The proceudres of heat and alcohol denaturation, ion-exchange chromatography and gel filtration were used to purify the activating protein over 100-fold from crude human liver extracts. When the purified activating protein is analysed by polyacrylamide-gel disc electrophoresis, two closely migrating protein bands are seen. When purified activating protein is used to reconstitute the G(M2) ganglioside hydrolase activity, the rate of reaction is proportional to the amount of hexosaminidase A used. The activation is specific for G(M2) ganglioside and and hexosaminidase A. The activating protein did not stimulate hydrolysis of asialo-G(M2) ganglioside by either hexosaminidase A or B. Hexosaminidase B did not catalyse hydrolysis of G(M2) ganglioside with or without the activator. Kinetic experiments suggest the presence of an enzyme-activator complex. The dissociation constant of this complex is decreased when higher concentrations of substrate are used, suggesting the formation of a ternary complex between enzyme, activator and substrate. Determination of the molecular weight of the activating protein by gel-filtration and sedimentation-velocity methods gave values of 36000 and 39000 respectively.

Seroepidemiologic study of Epstein-Barr virus infections in a rural community

The prevalence and titers of antibodies to capsid antigens of Epstein-Barr virus ad to the diffuse and restricted components of the Epstein-Barr virus-induced early antigen complex were determined in 109 families of a semirural community in Louisiana. Titers of antibody to the capsid antigens larger than or equal to 10 were found in 84 percent of children aged two to five years, and the prevalence increased with age to nearly 100 percent. There was a positive but variable correlation of the prevalence of anti-capsid antigen reactivity with low socioeconomic status and crowding. An overrepresentation of high titers of antibody to capsid antigens was present in individuals with a past history of pneumonia and urinary tract infections. The geometric mean titers of antibody to capsid antigens were highest in early childhood, lowest in adolescence and young adulthood, and high in the elderly. Females in all age groups and tonsillectomized children showed a higher geometric mean titer than their male and nontonsillectomized counterparts, respectively. Antibodies to the early antigen complex were found rarely (8.2 percent) and only in sera with relatively high titers of antibody to capsid antigens.